Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 81
Filter
1.
Curr Med Chem ; 2023 Jul 13.
Article in English | MEDLINE | ID: mdl-37448363

ABSTRACT

Human papillomavirus (HPV) infections are the cause of warts, lesions and cancer, with different types of HPV causing different symptoms. HPV infections are the primary cause of cervical cancer. There are over 220 different types of HPV, and only nine of these can currently be vaccinated. There is a need to treat these viral infections without just treating the symptoms of the infection, as is currently the main method. There is a wide range of small molecules that have been used to inhibit various stages of the HPV infectious cycle. This review examined 132 small molecules from 121 studies that specifically target aspects of HPV infections. HPV DNA encodes for six early genes (E1 to E7, skipping E3) and two late genes (L1 and L2). According to the results, these targets for small molecule inhibitors fall into three categories: those targeting E1 and E2, targeting E6 and E7 and, finally, targeting L1 and L2. Inhibitors of E6 and E7 are the most widely studied targets, with the majority of HPV inhibition in this area. While compounds targeting both E1/E2 and E6/E7 have made it to clinical trials, there has been no significant advancement on the topic.

2.
Gerodontology ; 39(4): 425-428, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36218242

ABSTRACT

OBJECTIVE: To report on the use of a mandibular 3-implant overdenture with a novel implant distribution opposing a maxillary complete denture for the rehabilitation of an older edentulous patient. BACKGROUND: The use of oral implants with attachment systems of various numbers and designs to support removable partial and complete dentures is well documented with success and predictability. MATERIALS AND METHODS: An older edentulous patient with a mandibular implant-assisted removable partial denture was presented with failing remaining dentition. Teeth were extracted and a single midsymphyseal implant was placed. A mandibular overdenture on three implants with ball attachments in a tripod distribution was constructed to oppose a new maxillary complete denture made using a modified impression technique. RESULTS: Over 2 years of follow-up, no significant biological or mechanical complications were reported, and denture retention and stability remained optimum. CONCLUSION: Mandibular overdentures on three implants with ball attachments in a tripod distribution, opposing a maxillary complete denture, could be an alternative treatment option for the older edentulous patients.


Subject(s)
Dental Implants , Mouth, Edentulous , Humans , Denture, Overlay , Denture Retention , Dental Prosthesis, Implant-Supported/methods , Mandible , Denture, Complete, Lower
3.
J Food Sci ; 87(9): 4174-4187, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35975798

ABSTRACT

Fresh truffles which include black truffle (Tuber melanosporum Vittadini) deteriorate and lose aroma rapidly after harvest; therefore, postharvest processing via freeze-drying or encapsulation is an option to preserve truffle aroma for extended supply. However, the aroma profile that directly affects the truffle quality and consumer acceptance is influenced by processing and producers require processing options that balance processing feasibility with retention of a suitable aroma profile. This study aimed to determine the impact of freeze-drying and encapsulation on the profile of key volatiles, consumer discrimination, and overall sensory impression (aroma intensity, liking, and acceptability) of processed truffle products compared to the starting material (positive control). The study combined experimental-scale processing with GC-MS analysis and consumer sensory evaluation to compare and optimize postharvest processing options. Based on the results, some volatile changes were detected in the processed truffle products compared to the positive control which were aligned with the consumer discrimination (triangle test) and the aroma intensity score (consumer sensory test). Despite some chemical and sensory differences detected, the consumer panel did not have any preference for processed truffle products compared to the positive control. The overall finding indicates the potential value of processing truffles into a natural flavoring ingredient for food application via freeze-drying or encapsulation, which should be of great interest for the truffle and food industry. According to the correlation analysis, the consumer acceptance of a truffle product may be increased by retaining 1-octen-3-ol and methional, while reducing the amount of p-cresol in the product. PRACTICAL APPLICATION: The postharvest process of turning truffles into a food flavoring ingredient may cause undesirable volatile changes that would directly impact the aroma quality and consumer acceptance of the processed truffle products. Hence, the impacts of freeze-drying and encapsulation on the chemical and sensory profile of truffles were evaluated in this study. Overall, the results of the concurrent instrument and sensory analysis demonstrated that both freeze-drying and encapsulation are potential options for processing.


Subject(s)
Ascomycota , Volatile Organic Compounds , Flavoring Agents/analysis , Gas Chromatography-Mass Spectrometry , Odorants/analysis , Volatile Organic Compounds/analysis
4.
J Food Sci ; 87(8): 3482-3495, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35788997

ABSTRACT

This study aimed to develop a novel technique to retain and stabilize compounds contributing to truffle aroma by encapsulation using ß-cyclodextrin. Two experiments were conducted. In the first experiment, the key volatile profile and microbial population of products resulting from three different encapsulation methods, namely direct mixing method (M1), direct mixing followed by ethanol addition method (M2), and paste method (M3), were compared with untreated truffles (positive control) over a 90-day period. The M2-derived product was the least optimal for retaining key volatile compounds despite showing the lowest microbial population. There was no significant difference in the volatile profile of products derived from M1 and M3 on day 0. However, it was observed that the M3-derived product could retain its volatile profile better than the M1-derived product by day 90. M3 was compared with freeze-drying in the second experiment. Freeze-dried truffles showed an overall higher relative percentage of volatiles than the M3-derived product on day 0. However, by day 90, some volatile changes occurred in the freeze-dried truffles but not in the M3-derived product. The findings indicate that while freeze-drying could adequately conserve truffle volatiles, the encapsulation of volatile compounds in ß-cyclodextrin could improve the volatile stability of truffle products and allow for longer storage times. Microbes were found in all encapsulated truffle products and freeze-dried truffles on days 0 and 90, suggesting the need to explore the possibility of incorporating a decontamination step in the process prior to either encapsulation or freeze-drying. PRACTICAL APPLICATION: A technique to capture and stabilize compounds responsible for truffle aroma by encapsulation using ß-cyclodextrin was developed and compared with freeze-drying in this study. The overall finding suggests that while freeze-drying of truffle could sufficiently preserve volatiles, encapsulating truffle volatiles with ß-cyclodextrin may improve its stability, extending its shelf life, which can be applied in the development of a natural truffle ingredient that can be applied in food product development.


Subject(s)
Ascomycota , Volatile Organic Compounds , beta-Cyclodextrins , Odorants
5.
Compr Rev Food Sci Food Saf ; 21(2): 1677-1701, 2022 03.
Article in English | MEDLINE | ID: mdl-35179824

ABSTRACT

Truffles are considered one of the world's most highly prized foods mainly due to their desirable organoleptic properties and rarity. However, truffles are seasonal (harvested mostly in winter from June to August in the Southern Hemisphere and from December to February in the Northern Hemisphere) and extremely perishable. Truffles deteriorate rapidly showing undesirable changes within 10 days from harvest in aroma and visual appearance after harvest. The very short postharvest shelf life (about 7-10 days) limits the potential for export and domestic consumption all year round. Several preservation methods have been studied to prolong their shelf life without the loss of aroma. However, all traditional preservation techniques have their own shortcomings and remain challenging. The extraction of natural truffle aroma volatiles for food applications could be a potential alternative to replace the existing synthetic flavoring used for processed truffle products. Four commonly used extraction methods for recovering volatile compounds from plants, namely, supercritical carbon dioxide extraction, Soxhlet extraction, distillation, and cold pressing, are critically analyzed. Up to date, existing research about the extraction of aroma volatiles from truffles is limited in the literature but based on the volatility of the key truffle volatile compounds, supercritical carbon dioxide extraction may offer the best possibility so that a natural truffle-based product that can be used in food applications throughout the year can be made available.


Subject(s)
Ascomycota , Biological Products , Carbon Dioxide , Flavoring Agents , Odorants/analysis
6.
Eur J Med Chem ; 226: 113861, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34624822

ABSTRACT

Human African Trypanosomiasis (HAT) is a neglected tropical disease caused by the parasitic protozoan Trypanosoma brucei (T. b.), and affects communities in sub-Saharan Africa. Previously, analogues of a tetrahydroisoquinoline scaffold were reported as having in vitro activity (IC50 = 0.25-70.5 µM) against T. b. rhodesiense. In this study the synthesis and antitrypanosomal activity of 80 compounds based around a core tetrahydroisoquinoline scaffold are reported. A detailed structure activity relationship was revealed, and five derivatives (two of which have been previously reported) with inhibition of T. b. rhodesiense growth in the sub-micromolar range were identified. Four of these (3c, 12b, 17b and 26a) were also found to have good selectivity over mammalian cells (SI > 50). Calculated logD values and preliminary ADME studies predict that these compounds are likely to have good absorption and metabolic stability, with the ability to passively permeate the blood brain barrier. This makes them excellent leads for a blood-brain barrier permeable antitrypanosomal scaffold.


Subject(s)
Tetrahydroisoquinolines/pharmacology , Trypanocidal Agents/pharmacology , Trypanosoma brucei rhodesiense/drug effects , Dose-Response Relationship, Drug , Molecular Structure , Parasitic Sensitivity Tests , Structure-Activity Relationship , Tetrahydroisoquinolines/chemical synthesis , Tetrahydroisoquinolines/chemistry , Trypanocidal Agents/chemical synthesis , Trypanocidal Agents/chemistry
7.
Adv Sci (Weinh) ; 8(19): e2101902, 2021 10.
Article in English | MEDLINE | ID: mdl-34338438

ABSTRACT

Analysis of the epicuticular wax layer on the surface of plant leaves can provide a unique window into plant physiology and responses to environmental stimuli. Well-established analytical methodologies can quantify epicuticular wax composition, yet few methods are capable of imaging wax distribution in situ or in vivo. Here, the first report of Fourier transform infrared (FTIR) reflectance spectroscopic imaging as a non-destructive, in situ, method to investigate variation in epicuticular wax distribution at 25 µm spatial resolution is presented. The authors demonstrate in vivo imaging of alterations in epicuticular waxes during leaf development and in situ imaging during plant disease or exposure to environmental stressors. It is envisaged that this new analytical capability will enable in vivo studies of plants to provide insights into how the physiology of plants and crops respond to environmental stresses such as disease, soil contamination, drought, soil acidity, and climate change.


Subject(s)
Plant Diseases , Plant Epidermis/chemistry , Plant Physiological Phenomena , Stress, Physiological/physiology , Waxes/chemistry , Microscopy, Electron, Scanning , Plant Leaves/chemistry
8.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Article in English | MEDLINE | ID: mdl-34380738

ABSTRACT

Cardiomyogenesis, the process by which the body generates cardiomyocytes, is poorly understood. We have recently shown that Sfrp2 promotes cardiomyogenesis in vitro. The objective of this study was to determine if Sfrp2 would similarly promote cardiomyogenesis in vivo. To test this hypothesis, we tracked multipotent cKit(+) cells in response to Sfrp2 treatment. In control adult mice, multipotent cKit(+) cells typically differentiated into endothelial cells but not cardiomyocytes. In contrast, Sfrp2 switched the fate of these cells. Following Sfrp2 injection, multipotent cKit(+) cells differentiated solely into cardiomyocytes. Sfrp2-derived cardiomyocytes integrated into the myocardium and exhibited identical physiological properties to preexisting native cardiomyocytes. The ability of Sfrp2 to promote cardiomyogenesis was further supported by tracking EdU-labeled cells. In addition, Sfrp2 did not promote the formation of new cardiomyocytes when the cKit(+) cell population was selectively ablated in vivo using a diphtheria toxin receptor-diphtheria toxin model. Notably, Sfrp2-induced cardiomyogenesis was associated with significant functional improvements in a cardiac injury model. In summary, our study further demonstrates the importance of Sfrp2 in cardiomyogenesis.


Subject(s)
Membrane Proteins/pharmacology , Myocardial Infarction/therapy , Animals , Calcium/metabolism , Cell Differentiation , Gene Expression Regulation , Membrane Proteins/metabolism , Mice , Mice, Transgenic , Myocardial Contraction/physiology , Myocytes, Cardiac
9.
Cochrane Database Syst Rev ; 4: CD010176, 2021 04 26.
Article in English | MEDLINE | ID: mdl-33899930

ABSTRACT

BACKGROUND: Alveolar bone changes following tooth extraction can compromise prosthodontic rehabilitation. Alveolar ridge preservation (ARP) has been proposed to limit these changes and improve prosthodontic and aesthetic outcomes when implants are used. This is an update of the Cochrane Review first published in 2015. OBJECTIVES: To assess the clinical effects of various materials and techniques for ARP after tooth extraction compared with extraction alone or other methods of ARP, or both, in patients requiring dental implant placement following healing of extraction sockets. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 19 March 2021), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2021, Issue 2), MEDLINE Ovid (1946 to 19 March 2021), Embase Ovid (1980 to 19 March 2021), Latin American and Caribbean Health Science Information database (1982 to 19 March 2021), Web of Science Conference Proceedings (1990 to 19 March 2021), Scopus (1966 to 19 March 2021), ProQuest Dissertations and Theses (1861 to 19 March 2021), and OpenGrey (to 19 March 2021). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. A number of journals were also handsearched. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) on the use of ARP techniques with at least six months of follow-up. Outcome measures were: changes in the bucco-lingual/palatal width of alveolar ridge, changes in the vertical height of the alveolar ridge, complications, the need for additional augmentation prior to implant placement, aesthetic outcomes, implant failure rates, peri-implant marginal bone level changes, changes in probing depths and clinical attachment levels at teeth adjacent to the extraction site, and complications of future prosthodontic rehabilitation. DATA COLLECTION AND ANALYSIS: We selected trials, extracted data, and assessed risk of bias in duplicate. Corresponding authors were contacted to obtain missing information. We estimated mean differences (MD) for continuous outcomes and risk ratios (RR) for dichotomous outcomes, with 95% confidence intervals (95% CI). We constructed 'Summary of findings' tables to present the main findings and assessed the certainty of the evidence using GRADE. MAIN RESULTS: We included 16 RCTs conducted worldwide involving a total of 524 extraction sites in 426 adult participants. We assessed four trials as at overall high risk of bias and the remaining trials at unclear risk of bias. Nine new trials were included in this update with six new trials in the category of comparing ARP to extraction alone and three new trials in the category of comparing different grafting materials. ARP versus extraction: from the seven trials comparing xenografts with extraction alone, there is very low-certainty evidence of a reduction in loss of alveolar ridge width (MD -1.18 mm, 95% CI -1.82 to -0.54; P = 0.0003; 6 studies, 184 participants, 201 extraction sites), and height (MD -1.35 mm, 95% CI -2.00 to -0.70; P < 0.0001; 6 studies, 184 participants, 201 extraction sites) in favour of xenografts, but we found no evidence of a significant difference for the need for additional augmentation (RR 0.68, 95% CI 0.29 to 1.62; P = 0.39; 4 studies, 154 participants, 156 extraction sites; very low-certainty evidence) or in implant failure rate (RR 1.00, 95% CI 0.07 to 14.90; 2 studies, 70 participants/extraction sites; very low-certainty evidence). From the one trial comparing alloplasts versus extraction, there is very low-certainty evidence of a reduction in loss of alveolar ridge height (MD -3.73 mm; 95% CI -4.05 to -3.41; 1 study, 15 participants, 60 extraction sites) in favour of alloplasts. This single trial did not report any other outcomes. Different grafting materials for ARP: three trials (87 participants/extraction sites) compared allograft versus xenograft, two trials (37 participants, 55 extraction sites) compared alloplast versus xenograft, one trial (20 participants/extraction sites) compared alloplast with and without membrane, one trial (18 participants, 36 extraction sites) compared allograft with and without synthetic cell-binding peptide P-15, and one trial (30 participants/extraction sites) compared alloplast with different particle sizes. The evidence was of very low certainty for most comparisons and insufficient to determine whether there are clinically significant differences between different ARP techniques based on changes in alveolar ridge width and height, the need for additional augmentation prior to implant placement, or implant failure. We found no trials which evaluated parameters relating to clinical attachment levels, specific aesthetic or prosthodontic outcomes for any of the comparisons. No serious adverse events were reported with most trials indicating that the procedure was uneventful. Among the complications reported were delayed healing with partial exposure of the buccal plate at suture removal, postoperative pain and swelling, moderate glazing, redness and oedema, membrane exposure and partial loss of grafting material, and fibrous adhesions at the cervical part of previously preserved sockets, for the comparisons xenografts versus extraction, allografts versus xenografts, alloplasts versus xenografts, and alloplasts with and without membrane. AUTHORS' CONCLUSIONS: ARP techniques may minimise the overall changes in residual ridge height and width six months after extraction but the evidence is very uncertain. There is lack of evidence of any differences in the need for additional augmentation at the time of implant placement, implant failure, aesthetic outcomes, or any other clinical parameters due to lack of information or long-term data. There is no evidence of any clinically significant difference between different grafting materials and barriers used for ARP. Further long-term RCTs that follow CONSORT guidelines (www.consort-statement.org) are necessary.


Subject(s)
Alveolar Process , Biocompatible Materials/administration & dosage , Dental Implantation, Endosseous , Organ Sparing Treatments/methods , Tooth Extraction/adverse effects , Tooth Socket , Adult , Alveolar Ridge Augmentation , Bias , Bone Regeneration , Bone Remodeling , Confidence Intervals , Heterografts , Humans , Middle Aged , Randomized Controlled Trials as Topic , Time Factors , Tooth Extraction/methods , Treatment Outcome
10.
Chem Biol Drug Des ; 97(6): 1137-1150, 2021 06.
Article in English | MEDLINE | ID: mdl-33638304

ABSTRACT

Several rationally designed isoniazid (INH), pyrazinamide (PZA) and ciprofloxacin (CPF) derivatives were conveniently synthesized and evaluated in vitro against H37Rv Mycobacterium tuberculosis (M. tb) strain. CPF derivative 16 displayed a modest activity (MIC = 16 µg/ml) and was docked into the M. tb DNA gyrase. Isoniazid-pyrazinoic acid (INH-POA) hybrid 21a showed the highest potency in our study (MIC = 2 µg/ml). It also retained its high activity against the other tested M. tb drug-sensitive strain (DS) V4207 (MIC = 4 µg/ml) and demonstrated negligible cytotoxicity against Vero cells (IC50  ≥ 64 µg/ml). Four tested drug-resistant (DR) M. tb strains were refractory to 21a, similar to INH, whilst being sensitive to CPF. Compound 21a was also inactive against two non-tuberculous mycobacterial (NTM) strains, suggesting its selective activity against M. tb. The noteworthy activity of 21a against DS strains and its low cytotoxicity highlight its potential to treat DS M. tb.


Subject(s)
Antitubercular Agents/chemical synthesis , Ciprofloxacin/analogs & derivatives , Isoniazid/analogs & derivatives , Pyrazinamide/analogs & derivatives , Animals , Antitubercular Agents/metabolism , Antitubercular Agents/pharmacology , Binding Sites , Catalytic Domain , Cell Survival/drug effects , Chlorocebus aethiops , Ciprofloxacin/chemistry , Ciprofloxacin/metabolism , Ciprofloxacin/pharmacology , DNA Gyrase/chemistry , DNA Gyrase/metabolism , Drug Design , Drug Resistance, Bacterial/drug effects , Isoniazid/metabolism , Isoniazid/pharmacology , Microbial Sensitivity Tests , Molecular Conformation , Molecular Docking Simulation , Mycobacterium tuberculosis/drug effects , Nontuberculous Mycobacteria/drug effects , Pyrazinamide/metabolism , Pyrazinamide/pharmacology , Structure-Activity Relationship , Vero Cells
11.
RSC Adv ; 11(26): 15497-15511, 2021 Apr 26.
Article in English | MEDLINE | ID: mdl-35481189

ABSTRACT

The omnipresent threat of tuberculosis (TB) and the scant treatment options thereof necessitate the development of new antitubercular agents, preferably working via a novel mechanism of action distinct from the current drugs. Various studies identified the mycobacterial membrane protein large 3 transporter (MmpL3) as the target of several classes of compounds, including the indole-2-caboxamides. Herein, several indoleamide analogues were rationally designed, synthesised, and evaluated for their antitubercular and antitumour activities. Compound 8g displayed the highest activity (MIC = 0.32 µM) against the drug-sensitive (DS) Mycobacterium tuberculosis (M. tb) H37Rv strain. This compound also exhibited high selective activity towards M. tb over mammalian cells [IC50 (Vero cells) = 40.9 µM, SI = 128], suggesting its minimal cytotoxicity. In addition, when docked into the MmpL3 active site, 8g adopted a binding profile similar to the indoleamide ligand ICA38. A related compound 8f showed dual antitubercular (MIC = 0.62 µM) and cytotoxic activities against paediatric glioblastoma multiforme (GBM) cell line KNS42 [IC50 (viability) = 0.84 µM]. Compound 8f also showed poor cytotoxic activity against healthy Vero cells (IC50 = 39.9 µM). Compounds 9a and 15, which were inactive against M. tb, showed potent cytotoxic (IC50 = 8.25 and 5.04 µM, respectively) and antiproliferative activities (IC50 = 9.85 and 6.62 µM, respectively) against KNS42 cells. Transcriptional analysis of KNS42 cells treated with compound 15 revealed a significant downregulation in the expression of the carbonic anhydrase 9 (CA9) and the spleen tyrosine kinase (SYK) genes. The expression levels of these genes in GBM tumours were previously shown to contribute to tumour progression, suggesting their involvement in our observed antitumour activities. Compounds 9a and 15 were selected for further evaluations against three different paediatric brain tumour cell lines (BT12, BT16 and DAOY) and non-neoplastic human fibroblast cells HFF1. Compound 9a showed remarkable cytotoxic (IC50 = 0.89 and 1.81 µM, respectively) and antiproliferative activities (IC50 = 7.44 and 6.06 µM, respectively) against the two tested atypical teratoid/rhabdoid tumour (AT/RT) cells BT12 and BT16. Interestingly, compound 9a was not cytotoxic when tested against non-neoplastic HFF1 cells [IC50 (viability) = 119 µM]. This suggests that an indoleamide scaffold can be fine-tuned to confer a set of derivatives with selective antitubercular and/or antitumour activities.

12.
Bioorg Chem ; 106: 104486, 2021 01.
Article in English | MEDLINE | ID: mdl-33276981

ABSTRACT

The treacherous nature of tuberculosis (TB) combined with the ubiquitous presence of the drug-resistant (DR) forms pose this disease as a growing public health menace. Therefore, it is imperative to develop new chemotherapeutic agents with a novel mechanism of action to circumvent the cross-resistance problems. The unique architecture of the Mycobacterium tuberculosis (M. tb) outer envelope plays a predominant role in its pathogenesis, contributing to its intrinsic resistance against available therapeutic agents. The mycobacterial membrane protein large 3 (MmpL3), which is a key player in forging the M. tb rigid cell wall, represents an emerging target for TB drug development. Several indole-2-carboxamides were previously identified in our group as potent anti-TB agents that act as inhibitor of MmpL3 transporter protein. Despite their highly potent in vitro activities, the lingering Achilles heel of these indoleamides can be ascribed to their high lipophilicity as well as low water solubility. In this study, we report our attempt to improve the aqueous solubility of these indole-2-carboxamides while maintaining an adequate lipophilicity to allow effective M. tb cell wall penetration. A more polar adamantanol moiety was incorporated into the framework of several indole-2-carboxamides, whereupon the corresponding analogues were tested for their anti-TB activity against drug-sensitive (DS) M. tb H37Rv strain. Three adamantanol derivatives 8i, 8j and 8l showed nearly 2- and 4-fold higher activity (MIC = 1.32 - 2.89 µM) than ethambutol (MIC = 4.89 µM). Remarkably, the most potent adamantanol analogue 8j demonstrated high selectivity towards DS and DR M. tb strains over mammalian cells [IC50 (Vero cells) ≥ 169 µM], evincing its lack of cytotoxicity. The top eight active compounds 8b, 8d, 8f, 8i, 8j, 8k, 8l and 10a retained their in vitro potency against DR M. tb strains and were docked into the MmpL3 active site. The most potent adamantanol/adamantane-based indoleamides 8j/8k displayed a two-fold surge in potency against extensively DR (XDR) M. tb strains with MIC values of 0.66 and 0.012 µM, respectively. The adamantanol-containing indole-2-carboxamides exhibited improved water solubility both in silico and experimentally, relative to the adamantane counterparts. Overall, the observed antimycobacterial and physicochemical profiles support the notion that adamantanol moiety is a suitable replacement to the adamantane scaffold within the series of indole-2-carboxamide-based MmpL3 inhibitors.


Subject(s)
Adamantane/pharmacology , Antitubercular Agents/pharmacology , Drug Design , Mycobacterium tuberculosis/drug effects , Tuberculosis, Multidrug-Resistant/drug therapy , Adamantane/analogs & derivatives , Adamantane/chemistry , Antitubercular Agents/chemical synthesis , Antitubercular Agents/chemistry , Dose-Response Relationship, Drug , Microbial Sensitivity Tests , Models, Molecular , Molecular Structure , Structure-Activity Relationship
13.
RSC Adv ; 10(13): 7523-7540, 2020 Feb 23.
Article in English | MEDLINE | ID: mdl-33014349

ABSTRACT

Our group has previously reported several indolecarboxamides exhibiting potent antitubercular activity. Herein, we rationally designed several arylcarboxamides based on our previously reported homology model and the recently published crystal structure of the mycobacterial membrane protein large 3 (MmpL3). Many analogues showed considerable anti-TB activity against drug-sensitive (DS) Mycobacterium tuberculosis (M. tb) strain. Naphthamide derivatives 13c and 13d were the most active compounds in our study (MIC: 6.55, 7.11 µM, respectively), showing comparable potency to the first line anti-tuberculosis (anti-TB) drug ethambutol (MIC: 4.89 µM). In addition to the naphthamide derivatives, we also identified the quinolone-2-carboxamides and 4-arylthiazole-2-carboxamides as potential MmpL3 inhibitors in which compounds 8i and 18b had MIC values of 9.97 and 9.82 µM, respectively. All four compounds retained their high activity against multidrug-resistant (MDR) and extensively drug-resistant (XDR) M. tb strains. It is worth noting that the two most active compounds 13c and 13d also exhibited the highest selective activity towards DS, MDR and XDR M. tb strains over mammalian cells [IC50 (Vero cells) ≥ 227 µM], indicating their potential lack of cytotoxicity. The four compounds were docked into the MmpL3 active site and were studied for their drug-likeness using Lipinski's rule of five.

14.
Am J Physiol Renal Physiol ; 318(2): F285-F297, 2020 02 01.
Article in English | MEDLINE | ID: mdl-31760770

ABSTRACT

Juxtaglomerular (JG) cells, major sources of renin, differentiate from metanephric mesenchymal cells that give rise to JG cells or a subset of smooth muscle cells of the renal afferent arteriole. During periods of dehydration and salt deprivation, renal mesenchymal stromal cells (MSCs) differentiate from JG cells. JG cells undergo expansion and smooth muscle cells redifferentiate to express renin along the afferent arteriole. Gene expression profiling comparing resident renal MSCs with JG cells indicates that the transcription factor Sox6 is highly expressed in JG cells in the adult kidney. In vitro, loss of Sox6 expression reduces differentiation of renal MSCs to renin-producing cells. In vivo, Sox6 expression is upregulated after a low-Na+ diet and furosemide. Importantly, knockout of Sox6 in Ren1d+ cells halts the increase in renin-expressing cells normally seen during a low-Na+ diet and furosemide as well as the typical increase in renin. Furthermore, Sox6 ablation in renin-expressing cells halts the recruitment of smooth muscle cells along the afferent arteriole, which normally express renin under these conditions. These results support a previously undefined role for Sox6 in renin expression.


Subject(s)
Arterioles/metabolism , Juxtaglomerular Apparatus/blood supply , Mesenchymal Stem Cells/metabolism , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/metabolism , Renin/metabolism , SOXD Transcription Factors/metabolism , Animals , Arterioles/drug effects , Blood Pressure , Cell Differentiation , Cell Proliferation , Cells, Cultured , Diet, Sodium-Restricted , Diuretics/pharmacology , Furosemide/pharmacology , Gene Expression Regulation , Male , Mesenchymal Stem Cells/drug effects , Mice, Inbred C57BL , Mice, Knockout , Muscle, Smooth, Vascular/drug effects , Myocytes, Smooth Muscle/drug effects , Renin/genetics , SOXD Transcription Factors/deficiency , SOXD Transcription Factors/genetics , Signal Transduction
15.
Curr Mol Pharmacol ; 12(1): 27-49, 2019.
Article in English | MEDLINE | ID: mdl-30360731

ABSTRACT

BACKGROUND: Mycolic acids (MAs) are the characteristic, integral building blocks for the mycomembrane belonging to the insidious bacterial pathogen Mycobacterium tuberculosis (M.tb). These C60-C90 long α-alkyl-ß-hydroxylated fatty acids provide protection to the tubercle bacilli against the outside threats, thus allowing its survival, virulence and resistance to the current antibacterial agents. In the post-genomic era, progress has been made towards understanding the crucial enzymatic machineries involved in the biosynthesis of MAs in M.tb. However, gaps still remain in the exact role of the phosphorylation and dephosphorylation of regulatory mechanisms within these systems. To date, a total of 11 serine-threonine protein kinases (STPKs) are found in M.tb. Most enzymes implicated in the MAs synthesis were found to be phosphorylated in vitro and/or in vivo. For instance, phosphorylation of KasA, KasB, mtFabH, InhA, MabA, and FadD32 downregulated their enzymatic activity, while phosphorylation of VirS increased its enzymatic activity. These observations suggest that the kinases and phosphatases system could play a role in M.tb adaptive responses and survival mechanisms in the human host. As the mycobacterial STPKs do not share a high sequence homology to the human's, there have been some early drug discovery efforts towards developing potent and selective inhibitors. OBJECTIVE: Recent updates to the kinases and phosphatases involved in the regulation of MAs biosynthesis will be presented in this mini-review, including their known small molecule inhibitors. CONCLUSION: Mycobacterial kinases and phosphatases involved in the MAs regulation may serve as a useful avenue for antitubercular therapy.


Subject(s)
Bacterial Proteins/metabolism , Mycobacterium tuberculosis/metabolism , Mycolic Acids/metabolism , Protein Serine-Threonine Kinases/metabolism , Bacterial Proteins/antagonists & inhibitors , Fatty Acid Synthases/antagonists & inhibitors , Fatty Acid Synthases/metabolism , Mycolic Acids/chemistry , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Tyrosine Phosphatases/antagonists & inhibitors , Protein Tyrosine Phosphatases/metabolism , Small Molecule Libraries/chemistry , Small Molecule Libraries/metabolism
16.
Cochrane Database Syst Rev ; 10: CD008001, 2018 10 11.
Article in English | MEDLINE | ID: mdl-30308116

ABSTRACT

BACKGROUND: Implant overdentures are one of the most common treatment options used to rehabilitate edentulous patients. Attachment systems are used to anchor the overdentures to implants. The plethora of attachment systems available dictates a need for clinicians to understand their prosthodontic and patient-related outcomes. OBJECTIVES: To compare different attachment systems for maxillary and mandibular implant overdentures by assessing prosthodontic success, prosthodontic maintenance, patient preference, patient satisfaction/quality of life and costs. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 24 January 2018); Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 12) in the Cochrane Library (searched 24 January 2018); MEDLINE Ovid (1946 to 24 January 2018); and Embase Ovid (1980 to 24 January 2018). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials on 24 January 2018. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: All randomised controlled trials (RCTs), including cross-over trials on maxillary or mandibular implant overdentures with different attachment systems with at least 1 year follow-up. DATA COLLECTION AND ANALYSIS: Four review authors extracted data independently and assessed risk of bias for each included trial. Several corresponding authors were subsequently contacted to obtain missing information. Fixed-effect meta-analysis was used to combine the outcomes with risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous outcomes, with 95% confidence intervals (95% CI). We used the GRADE approach to assess the quality of evidence and create 'Summary of findings' tables. MAIN RESULTS: We identified six RCTs with a total of 294 mandibular overdentures (including one cross-over trial). No trials on maxillary overdentures were eligible. Due to the poor reporting of the outcomes across the included trials, only limited analyses between mandibular overdenture attachment systems were possible.Comparing ball and bar attachments, upon pooling the data regarding short-term prosthodontic success, we identified substantial heterogeneity (I2 = 97%) with inconsistency in the direction of effect, which was unexplained by clinical or methodological differences between the studies, and accordingly we did not perform meta-analyses for this outcome. Short-term re-treatment (repair of attachment system) was higher with ball attachments (RR 3.11, 95% CI 1.68 to 5.75; 130 participants; 2 studies; very low-quality evidence), and there was no difference between both attachment systems in short-term re-treatment (replacement of attachment system) (RR 1.18, 95% CI 0.38 to 3.71; 130 participants; 2 studies; very low-quality evidence). It is uncertain whether there is a difference in short-term prosthodontic success when ball attachments are compared with bar attachments.Comparing ball and magnet attachments, there was no difference between them in medium-term prosthodontic success (RR 0.84, 95% CI 0.64 to 1.10; 69 participants; 1 study; very low-quality evidence), or in medium-term re-treatment (repair of attachment system) (RR 1.75, 95% CI 0.65 to 4.72; 69 participants; 1 study; very low-quality evidence). However, after 5 years, prosthodontic maintenance costs were higher when magnet attachments were used (MD -247.37 EUR, 95% CI -346.32 to -148.42; 69 participants; 1 study; very low-quality evidence). It is uncertain whether there is a difference in medium-term prosthodontic success when ball attachments are compared with magnet attachments.One trial provided data for ball versus telescopic attachments and reported no difference in prosthodontic maintenance between the two systems in short-term patrix replacement (RR 6.00, 95% CI 0.86 to 41.96; 22 participants; 1 study; very low-quality evidence), matrix activation (RR 11.00, 95% CI 0.68 to 177.72; 22 participants; 1 study; very low-quality evidence), matrix replacement (RR 1.75, 95% CI 0.71 to 4.31; 22 participants; 1 study; very low-quality evidence), or in relining of the implant overdenture (RR 2.33, 95% CI 0.81 to 6.76; 22 participants; 1 study; very low-quality evidence). It is uncertain whether there is a difference in short-term prosthodontic maintenance when ball attachments are compared with telescopic attachments.In the only cross-over trial included, patient preference between different attachment systems was assessed after only 3 months and not for the entire trial period of 10 years. AUTHORS' CONCLUSIONS: For mandibular overdentures, there is insufficient evidence to determine the relative effectiveness of different attachment systems on prosthodontic success, prosthodontic maintenance, patient satisfaction, patient preference or costs. In the short term, there is some evidence that is insufficient to show a difference and where there was no evidence was reported. It was not possible to determine any preferred attachment system for mandibular overdentures.For maxillary overdentures, there is no evidence (with no trials identified) to determine the relative effectiveness of different attachment systems on prosthodontic success, prosthodontic maintenance, patient satisfaction, patient preference or costs.Further RCTs on edentulous cohorts must pay attention to trial design specifically using the same number of implants of the same implant system, but with different attachment systems clearly identified in control and test groups. Trials should also determine the longevity of different attachment systems and patient preferences. Trials on the current array of computer-aided designed/computer-assisted manufactured (CAD/CAM) bar attachment systems are encouraged.


Subject(s)
Dental Implantation/methods , Denture, Overlay , Jaw, Edentulous/rehabilitation , Humans , Randomized Controlled Trials as Topic , Tooth Preparation, Prosthodontic , Treatment Outcome
17.
J Mol Cell Cardiol ; 123: 64-74, 2018 10.
Article in English | MEDLINE | ID: mdl-30171847

ABSTRACT

There is much interest over resident c-Kit(+) cells in tissue regeneration. Their role in cardiac regeneration has been controversial. In this study we aim to understand the in vivo behavior of cardiac c-Kit(+) cells at baseline and after myocardial infarction and in response to Sfrp2. This approach can accurately study the in vivo transcript expressions of these cells in temporal response to injury and overcomes the limitations of the in vitro approach. RNA-seq was performed with c-Kit(+) cells and cardiomyocytes from healthy non-injured mice as well as c-Kit(+) cells from 1 day post-MI and 12 days post-MI mice. When compared to in vivo c-Kit(+) cells isolated from a healthy non-injured mouse heart, cardiomyocytes were enriched in transcripts that express anion channels, cation channels, developmental/differentiation pathway components, as well as proteins that inhibit canonical Wnt/ß-catenin signaling. Myocardial infarction (MI) induced in vivo c-Kit(+) cells to transiently adopt the cardiomyocyte-specific signature: expression of a number of cardiomyocyte-specific transcripts was maximal 1 day post-MI and declined by 12 days post-MI. We next studied the effect of ß-catenin inhibition on in vivo c-Kit(+) cells by administering the Wnt inhibitor Sfrp2 into the infarct border zone. Sfrp2 both enhanced and sustained cardiomyocyte-specific gene expression in the in vivo c-Kit(+) cells: expression of cardiomyocyte-specific transcripts was higher and there was no decline in expression by 12 days post-MI. Further analysis of the biology of c-Kit(+) cells identified that culture induced a significant and irreversible change in their molecular signature raising questions about reliability of in vitro studies. Our findings provide evidence that MI induces in vivo c-Kit(+) cells to adopt transiently a cardiomyocyte-specific pattern of gene expression, and Sfrp2 further enhances and induces sustained gene expression. Our approach is important for understanding c-Kit(+) cells in cardiac regeneration and also has broad implications in the investigation of in vivo resident stem cells in other areas of tissue regeneration.


Subject(s)
Heart Injuries/etiology , Heart Injuries/metabolism , Myocytes, Cardiac/metabolism , Proto-Oncogene Proteins c-kit/metabolism , beta Catenin/antagonists & inhibitors , beta Catenin/metabolism , Animals , Cell Differentiation , Computational Biology/methods , Disease Models, Animal , Gene Expression Profiling , Gene Expression Regulation , Ion Channels/genetics , Ion Channels/metabolism , Mice , Mice, Knockout , Myoblasts/cytology , Myoblasts/drug effects , Myoblasts/metabolism , Myocardial Infarction/etiology , Myocardial Infarction/metabolism , Myocytes, Cardiac/cytology , Myocytes, Cardiac/drug effects , Organ Specificity/genetics , Wnt Signaling Pathway
18.
Anal Chem ; 90(17): 10256-10262, 2018 09 04.
Article in English | MEDLINE | ID: mdl-30073829

ABSTRACT

The electrochemical behavior and detection of sulfated carbohydrates were investigated at an array of microinterfaces between two immiscible electrolyte solutions where the organic phase was gelled. It was found that the electrochemical signal was dependent on the organic phase electrolyte cation. Cyclic voltammetry (CV) of sucrose octasulfate (SOS) with bis(triphenylphosphoranylidene)ammonium BTPPA+ as the organic phase cation did not provide a response to a 10 µM SOS concentration. However, when the organic phase cation was tetradodecylammonium TDDA+, a distinct peak was present in the CV at ca. -0.47 V, indicative of a desorption process following adsorption during the preceding scan. This detection peak shifted to ca. -0.28 V when tridodecylmethylammonium TDMA+ was the organic phase cation, indicating an increased binding strength between this alkylammonium cation and SOS. By combining electroadsorption with TDMA+ as the organic phase electrolyte cation, detection limits of 0.064 µM SOS in 10 mM LiCl and 0.16 µM in a synthetic urine aqueous phase were achieved. The detection limit was improved to 0.036 µM SOS (10 mM LiCl) when the electroadsorption time was increased to 180 s, indicating the analytical capability for the detection of SOS and related sugars by ion-transfer adsorptive stripping voltammetry.

19.
Cell Signal ; 46: 113-119, 2018 06.
Article in English | MEDLINE | ID: mdl-29499305

ABSTRACT

The development of biased agonist drugs is widely recognized to be important for the treatment of many diseases, including cardiovascular disease. While GPCR biased agonism has been heavily characterized there is a distinct lack of information with respect to RTK biased agonism both in the identification of biased agonists as well as their attendant mechanisms. One such RTK, the Insulin-like Growth Factor 1 Receptor (IGF1R) plays an important role in a range of biological and disease processes. The micropeptide LL37 has been described as a biased agonist of the IGF1R. We were interested to further understand the mechanism by which LL37 promotes biased signaling through the IGF1R. We found that LL37 biased agonism is dependent on ß-arrestin 2. Moreover, BRET assays indicated that LL37 biased agonism is explained by the inability of LL37 to promote the recruitment of IRS1 to the IGF1R compared to IGF1. LL37 promotes an altered association of IGF1R with GRK6, which could also serve as an explanation for bias. We also demonstrated a functional consequence of this bias by showing that while LL37 can promote cell proliferation, it does not induce protein synthesis, unlike IGF1, which does both. We have recently identified HASF, a natural protein released by mesenchymal stem cells, as a novel ligand of the IGF1R. HASF is a paracrine factor with potent cardioprotective and cardio-regenerative properties which also acts via IGF1R biased signaling, preferentially activated ERK over Akt.


Subject(s)
Adaptor Proteins, Vesicular Transport/pharmacology , Antimicrobial Cationic Peptides/pharmacology , Heart Ventricles/metabolism , Membrane Proteins/pharmacology , Myoblasts, Cardiac/metabolism , Paracrine Communication/drug effects , Receptor, IGF Type 1/metabolism , beta-Arrestin 2/metabolism , Adaptor Proteins, Vesicular Transport/physiology , Animals , Antimicrobial Cationic Peptides/physiology , Cell Line , Cell Proliferation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , G-Protein-Coupled Receptor Kinases/metabolism , HEK293 Cells , Heart Ventricles/cytology , Humans , Membrane Proteins/physiology , Mice, Knockout , Myoblasts, Cardiac/cytology , Rats , Signal Transduction/drug effects , Cathelicidins
20.
Resuscitation ; 125: 99-103, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29425976

ABSTRACT

BACKGROUND: Little is known about hemodynamics in adult, out-of-hospital (OHCA) patients following return of spontaneous circulation (ROSC). A 1994 study when "high-dose epinephrine" use was common showed consistently elevated systemic vascular resistance (SVR) lasting ≥6 h in 49 adult patients after return of spontaneous circulation (ROSC). STUDY AIM: To characterize hemodynamic abnormalities in adult OHCA patients soon after ROSC. Our hypothesis was that, unlike the consistently high SVR values reported when "high-dose" epinephrine was in common use, there would be a more heterogenous distribution of SVR values using current adrenergic therapy. METHODS: We included adult, OHCA patients transported by paramedics to the Emergency Department (ED) post-ROSC. Children, prisoners, pregnant women, and those with ongoing CPR or arrest due to traumatic injury were excluded. Hemodynamics were recorded non-invasively as soon as feasible after ED arrival but were not used to influence therapy, which was guided by clinical judgment of treating ED physicians. RESULTS: Hemodynamics were recorded on 30 patients 20 [16,25] minutes after ED arrival: 50% had a normal SVR, 30% had a high SVR, and 20% had a low SVR. There was no difference in survival to admission among groups, although there was a difference among groups in survival to discharge. Comparing the low SVR group vs the combined normal and high group revealed a trend for fewer 0/6 (0%) low vs. 10/24 (42%) normal or high SVR patients surviving to hospital discharge (p = .053). CONCLUSION: A heterogeneous range of hemodynamic states exist post-ROSC rather than consistent vasoconstriction. Adequately powered, randomized clinical trials will be needed to determine whether noninvasively-derived, hemodynamic-directed therapy can play a role in improving neurologically-intact survival following OHCA in adults.


Subject(s)
Cardiopulmonary Resuscitation/statistics & numerical data , Emergency Service, Hospital/statistics & numerical data , Out-of-Hospital Cardiac Arrest/mortality , Vascular Resistance , Cardiopulmonary Resuscitation/methods , Epinephrine/therapeutic use , Female , Hemodynamics , Humans , Male , Middle Aged , Out-of-Hospital Cardiac Arrest/drug therapy , Out-of-Hospital Cardiac Arrest/physiopathology , Prospective Studies , Time Factors , Time-to-Treatment , Vasoconstrictor Agents/therapeutic use
SELECTION OF CITATIONS
SEARCH DETAIL
...