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1.
Clin Chim Acta ; 557: 117857, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484908

RESUMO

BACKGROUND: The prevalence of type 2 diabetes mellitus (T2DM), a progressive metabolic disorder characterized by chronic hyperglycemia and the development of insulin resistance, has increased globally, with worrying statistics coming from children, adolescents, and young adults from developing countries like India. Here, we investigated unique circulating metabolic signatures associated with prediabetes and T2DM in an Indian cohort using NMR-based metabolomics. MATERIALS AND METHODS: The study subjects included healthy volunteers (N = 101), prediabetic subjects (N = 75), and T2DM patients (N = 108). Serum metabolic profiling was performed using 1H NMR spectroscopy and major perturbed metabolites were identified by multivariate analysis and receiver operating characteristic (ROC) modules. RESULTS: Of the 36 aqueous abundant metabolites, 24 showed a statistically significant difference between healthy volunteers, prediabetics, and established T2DM subjects. On performing multivariate ROC curve analysis with 5 commonly dysregulated metabolites (namely, glucose, pyroglutamate, o-phosphocholine, serine, and methionine) in prediabetes and T2DM, AUC values obtained were 0.96 (95 % confidence interval (CI) = 0.93, 0.98) for T2DM; and 0.88 (95 % CI = 0.81, 0.93) for prediabetic subjects, respectively. CONCLUSION: We propose that the identified metabolite panel can be used in the future as a biomarker for clinical diagnosis, patient surveillance, and for predicting individuals at risk for developing diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Adolescente , Criança , Adulto Jovem , Humanos , Estado Pré-Diabético/diagnóstico , Hemoglobinas Glicadas , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Biomarcadores
2.
Res Psychother ; 27(1)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38497293

RESUMO

Internationally, there is ongoing concern about accessibility to mental health care and training. The goal of this study was to explore commonalities and differences within models of clinical psychology and psychotherapy in Ontario, Canada, and Lombardia, Italy, respectively, to inform improvements to the accessibility of mental health care and training. Using key informant sampling, we recruited ten students and professionals in Italy and Canada who study or work in psychology for semi-structured interviews. We analyzed the interview content using an inductive approach for thematic analysis within countries and meta-theme analysis across countries. The findings indicated three cross-national meta-themes: the need to integrate evidence with practice, the limited accessibility of training for students and treatment for patients, and the importance of the quality of training programs. Despite some differences regarding the amount of scientific training, personal therapy for trainees, and the prominence of cultural diversity training, Canadian and Italian psychology professionals and students shared experiences of psychotherapy practice and clinical psychology training. The three cross-national meta-themes indicate which issues in training and practice may be relevant worldwide and where to focus resources. The findings can inform international collaborations regarding training model structures that may increase access to psychology training and may increase consensus on professional recognition standards to improve mobility for professionals. These changes could reduce barriers to mental healthcare services for patients.

3.
J Pharm Biomed Anal ; 235: 115605, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37531734

RESUMO

Ion channels and transporters play key roles in various biological processes, including cell proliferation and programmed cell death. Recently, we reported that 2,4-dinitrobenzene-sulfonyl-protected N1,N3-dihexy-2-hydroxyisophthalamide (1) forms ion channels upon activation by glutathione (GSH) and results in the induction of apoptosis by depleting the intracellular GSH reservoir in cancer cells. However, the detailed molecular events leading to the induction of apoptosis by these synthetic transport systems in cancer cells still need to be uncovered. Along these lines, we investigated the alterations in cellular metabolites and the associated metabolic pathways by performing untargeted global metabolic profiling of breast cancer cells - MCF-7 - using 1H NMR-based metabolomics. The evaluation of spectral profiles from MCF-7 cells exposed to 1 and their comparison with those corresponding to untreated (control) cells identified 14 significantly perturbed signature metabolites. These metabolites belonged mostly to antioxidant defence, energy metabolism, amino acid biosynthesis, and lipid metabolism pathways and included GSH, o-phosphocholine, malate, and aspartate, to name a few. These results would help us gain deeper insights into the molecular mechanism underlying 1-mediated cytotoxicity of MCF-7 cells and eventually help identify potential novel therapeutic targets for more effective cancer management.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Metabolômica/métodos , Células MCF-7 , Apoptose , Glutationa/metabolismo
4.
J Med Educ Curric Dev ; 10: 23821205231164088, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324053

RESUMO

OBJECTIVES: Few medical schools incorporate formal education on human trafficking (HT) and sex trafficking (ST) into their curriculum. Our objective was to develop, implement, and evaluate education on HT and ST in the first-year medical student curriculum. METHODS: The curriculum included a standardized patient (SP) experience and lecture. As part of their mandatory sexual health course, students interviewed an SP who presented with red flags for ST and then participated in a discussion led by a physician-facilitator in an observed small group setting. A multiple-choice survey to assess knowledge about HT and ST was developed and administered to students before and after the SP interview. RESULTS: Of the 50 first-year medical students, 29 (58%) participated in the survey. Compared with the students' baseline scores (according to the percentage of correct responses), scores after the educational intervention showed a significant increase in percentage correct on questions related to trafficking definition and scope (elder care, P = .01; landscaping, P = .03); victim identification (P < .001); referral to services (P < .001); legal issues (P = .01); and security (P < .001). On the basis of the feedback, a 2-hour lecture, which was adapted from the American Medical Women's Association-Physicians Against the Trafficking of Humans "Learn to Identify and Fight Trafficking" training, was presented the next year to all first-year medical students as part of their longitudinal clinical skills course and before the SP case. Curriculum objectives included learning trafficking definitions, victim/survivor identification, intersections with health care, the local impact of HT, and available resources. CONCLUSION: This curriculum fulfills course objectives and could be replicated at other institutions. Further evaluation of this pilot curriculum is necessary to evaluate its effectiveness.

5.
Eur J Med Chem ; 240: 114577, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35810535

RESUMO

Visceral leishmaniasis is a potentially fatal disease caused by the parasitic protists, Leishmania donovani and L. infantum. Current treatments remain unsuitable due to cost, the need for hospitalization, variable efficacy against different species, toxicity and emerging resistance. Herein, we report the SAR exploration of the novel hit 4-Fluoro-N-(5-(4-methoxyphenyl)-1-methyl-1H-imidazole-2-yl)benzamide [1] previously identified from a high throughput screen against Trypanosoma brucei, Trypanosoma cruzi and Leishmania donovani. An extensive and informative set of analogues were synthesized incorporating key modifications around the scaffold resulting in improved potency, whilst the majority of compounds maintained low cytotoxicity against human THP-1 macrophages that are target cells for these pathogens. New lead compounds identified within this study also maintained desirable physicochemical properties, improved metabolic stability in vitro and displayed no significant mitotoxicity against HepG2 cell lines. This compound class warrants continued investigation towards development as a novel treatment for Visceral Leishmaniasis.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Visceral , Trypanosoma cruzi , Antiprotozoários/química , Humanos , Imidazóis/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico
6.
ACS Biomater Sci Eng ; 8(4): 1573-1582, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35353486

RESUMO

Influenza virus is a major cause of death on a global scale. Seasonal vaccines have been developed to combat influenza; however, they are not always highly effective. One strategy to develop a more broadly active influenza vaccine is the use of multiple rounds of layered consensus buildings to generate recombinant antigens, termed computationally optimized broadly reactive antigen (COBRA). Immunization with the COBRA hemagglutinin (HA) can elicit broad protection against multiple strains of a single influenza subtype (e.g., H1N1). We formulated a COBRA H1 HA with a stimulator of interferon genes agonist cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) into a nasal gel for vaccination against influenza. The gel formulation was designed to increase mucoadhesion and nasal retention of the antigen and adjuvant to promote a strong mucosal response. It consisted of a Schiff base-crosslinked hydrogel between branched polyethyleneimine and oxidized dextran. Following a prime-boost-boost schedule, an intranasal gel containing cGAMP and model antigen ovalbumin (OVA) led to the faster generation of serum IgG, IgG1, and IgG2c and significantly greater serum IgG1 levels on day 42 compared to soluble controls. Additionally, OVA-specific IgA was detected in nasal, vaginal, and fecal samples for all groups, except the vehicle control. When the COBRA HA was given intranasally in a prime-boost schedule, the mice receiving the gel containing the COBRA and cGAMP had significantly higher serum IgG and IgG2c at day 41 compared to all groups, and only this group had IgA levels above the background in vaginal, nasal, and fecal samples. Overall, this study indicates the utility of an intranasal gel for the delivery of COBRAs for the generation of serum and mucosal humoral responses.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Animais , Anticorpos Antivirais , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Imunoglobulina A , Imunoglobulina G , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/prevenção & controle , Camundongos , Infecções por Orthomyxoviridae/prevenção & controle
7.
Pest Manag Sci ; 77(11): 5001-5020, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34227215

RESUMO

BACKGROUND: In this study, we surveyed through a structured and pilot-tested questionnaire, the practices of pesticide usage by small-scale (< 1.25 ha) chilli and tomato farmers from four districts of Sri Lanka and their perceptions on the effectiveness of pesticides and willingness to adopt integrated pest management (IPM). RESULTS: We found significant (P < 0.05) variation among districts in farmer responses to 37 out of 59 survey questions. A majority of farmers were dependent on pesticides with only a minority practicing IPM. A majority perceived that their current pesticide usage was increasing, but was not excessive. A majority were aware of the negative impacts of pesticides on human health and environment. Farmer perception on the effectiveness of pesticides increased with age, but was not influenced by education level. Farmers having a higher opinion of pesticides made a greater number of applications during a cropping cycle. They also maintained a longer preharvest interval and did not use pesticide mixtures. A majority expressed willingness to initiate IPM, but identified lack of knowledge and technical knowhow on specific IPM practices for their crops as barriers to adoption and requested external support. Farmer willingness to adopt IPM is higher among older, more educated farmers and among full-time farmers who are currently totally-dependent on pesticides and whose major income source was farming. CONCLUSION: We conclude that a significant extension effort in terms of farmer education on IPM and external assistance to develop the technological knowhow, which is tailor-made to specific districts, is needed to facilitate adoption of IPM among these farmers.


Assuntos
Exposição Ocupacional , Praguicidas , Solanum lycopersicum , Agricultura , Fazendeiros , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Percepção , Sri Lanka
8.
FEMS Microbiol Lett ; 368(11)2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34089315

RESUMO

Host-directed therapies (HDTs) could enhance the activity of traditional antibiotics. AR-12 is a promising HDT against intracellular pathogens including Salmonella enterica serovar Typhimurium, and has been shown to act through modulation of autophagy and the Akt kinase pathway. Since AR-12 does not inhibit the growth of planktonic bacteria but only works in conjunction with the infected host-cell, we hypothesized that AR-12 could enhance the activity of antibiotics in less-susceptible strains in the intracellular host environment. We found that repetitive passaging of S. typhimurium in macrophages in the absence of antibiotics led to a 4-fold reduction in their intracellular susceptibility to streptomycin (STR), but had no effect on the bacteria's sensitivity to AR-12. Moreover, when the host-passaged strains were treated with a combined therapy of AR-12 and STR, there was a significant reduction of intracellular bacterial burden compared to STR monotherapy. Additionally, co-treatment of macrophages infected with multi-drug resistant S. typhimurium with AR-12 and STR or ampicillin showed enhanced clearance of the intracellular bacteria. The drug combination did not elicit this effect on planktonic bacteria. Overall, AR-12 enhanced the clearance of less susceptible S. typhimurium in an intracellular environment.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Pirazóis/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Sinergismo Farmacológico , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos , Testes de Sensibilidade Microbiana , Células RAW 264.7 , Estreptomicina/farmacologia
9.
ACS Biomater Sci Eng ; 7(5): 1725-1741, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33966377

RESUMO

Visceral leishmaniasis (VL) is a deadly, vector-borne, neglected tropical disease endemic to arid parts of the world and is caused by a protozoan parasite of the genus Leishmania. Chemotherapy is the primary treatment for this systemic disease, and multiple potent therapies exist against this intracellular parasite. However, several factors, such as systemic toxicity, high costs, arduous treatment regimen, and rising drug resistance, are barriers for effective therapy against VL. Material-based platforms have the potential to revolutionize chemotherapy for leishmaniasis by imparting a better pharmacokinetic profile and creating patient-friendly routes of administration, while also lowering the risk for drug resistance. This review highlights promising drug delivery strategies and novel therapies that have been evaluated in preclinical models, demonstrating the potential to advance chemotherapy for VL.


Assuntos
Leishmania donovani , Leishmania infantum , Leishmaniose Visceral , Sistemas de Liberação de Medicamentos , Humanos , Leishmaniose Visceral/tratamento farmacológico
10.
Transplant Proc ; 53(5): 1509-1513, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33892934

RESUMO

BACKGROUND: Kidneys from very young pediatric donors continue to be underutilized. To reduce discard, the Organ Procurement and Transplantation Network (OPTN) policy was recently updated to allow kidneys from donors weighing <18 kg to be recovered en bloc. METHODS: We reviewed our center's experience with kidney transplantation in adult recipients of <18 kg pediatric donor kidneys to assess renal function outcomes specific to solitary vs en bloc usage. RESULTS: The majority of <18 kg donors were used en bloc (n = 39, 72.2% vs n = 15, 27.8%). Donor weight (kg) was similar between the 2 groups (12.3 ± 3.2 vs 14.1 ± 2.5, P = .05). Recipient weight was lower in the solitary kidney group (P = .01). Both groups had a similar donor-to-recipient body weight ratio (0.24 ± 0.3 vs 0.18 ± 0.3, P = .51). The solitary kidney group had a lower estimated glomerular filtration rate at 1 (56.9 ± 24.3 vs 81.8 ± 24.8, P = .01) and 2 years (72 ± 18.6 vs 93.7 ± 21.6, P = .03). By 2 years, both groups had an average estimated glomerular filtration rate >60 mL/min. Kidney allograft growth occurred in both groups, with the largest increase occurring the first month posttransplant (11.9%, 18.6%, P < .0001). CONCLUSION: For pediatric donors weighing <18 kg, improvements in renal function continue beyond the first posttransplant year. Risk for hyperfiltration injury appears low and renal mass-recipient mass matching is useful in guiding decision-making for solitary vs en bloc utilization.


Assuntos
Seleção do Doador/métodos , Sobrevivência de Enxerto/fisiologia , Transplante de Rim/métodos , Obtenção de Tecidos e Órgãos/métodos , Adulto , Peso Corporal , Criança , Pré-Escolar , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/patologia , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doadores de Tecidos/estatística & dados numéricos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/provisão & distribuição , Transplantes/patologia , Transplantes/fisiopatologia , Resultado do Tratamento
11.
Clin Transplant ; 35(5): e14279, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33690907

RESUMO

Kidney transplant (KT) outcomes from high kidney donor profile index (KDPI ≥85%) donors with acute kidney injury (AKI) remain underreported. KT from 172 high KDPI Acute Kidney Injury Network (AKIN) stage 0-1 donors and 76 high KDPI AKIN stage 2-3 donors from a single center were retrospectively assessed. The AKIN 2-3 cohort had more delayed graft function (71% vs. 37%, p < .001). At one year, there were no differences in the estimated glomerular filtration rate (44 ± 17 vs. 46 ± 18, p = .42) or fibrosis on protocol biopsy (ci, p = .85). Donor terminal creatinine (p = .59) and length of delayed graft function (p = .39) did not impact one-year eGFR. There were more primary nonfunction (PNF) events in the high KDPI AKIN 2-3 group (5.3% vs. 0.6%, p = .02). With a median follow-up of 3.8 years, one-year death-censored graft failure was 3.5% for AKIN 0-1 and 14.5% for AKIN 2-3 (HR 2.40, 95% CI 1.24-4.63, p = .01). Although AKIN stage 2-3 high KDPI kidneys had comparable one-year eGFR to AKIN stage 0-1 high KDPI kidneys, there were more PNF occurrences and one-year death-censored graft survival was reduced. Given these findings, additional precautions should be undertaken when assessing and utilizing kidneys from severe AKI high KDPI donors.


Assuntos
Injúria Renal Aguda , Doadores de Tecidos , Sobrevivência de Enxerto , Humanos , Rim , Estudos Retrospectivos
12.
Biol Chem ; 402(2): 179-194, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33544469

RESUMO

The aberrant misfolding and self-assembly of human islet amyloid polypeptide (hIAPP)-a hormone that is co-secreted with insulin from pancreatic ß-cells-into toxic oligomers, protofibrils and fibrils has been observed in type 2 diabetes mellitus (T2DM). The formation of these insoluble aggregates has been linked with the death and dysfunction of ß-cells. Therefore, hIAPP aggregation has been identified as a therapeutic target for T2DM management. Several natural products are now being investigated for their potential to inhibit hIAPP aggregation and/or disaggregate preformed aggregates. In this study, we attempt to identify the anti-amyloidogenic potential of Myricetin (MYR)- a polyphenolic flavanoid, commonly found in fruits (like Syzygium cumini). Our results from biophysical studies indicated that MYR supplementation inhibits hIAPP aggregation and disaggregates preformed fibrils into non-toxic species. This protection was accompanied by inhibition of oxidative stress, reduction in lipid peroxidation and the associated membrane damage and restoration of mitochondrial membrane potential in INS-1E cells. MYR supplementation also reversed the loss of functionality in hIAPP exposed pancreatic islets via restoration of glucose-stimulated insulin secretion. Molecular dynamics simulation studies suggested that MYR molecules interact with the hIAPP pentameric fibril model at the amyloidogenic core region and thus prevents aggregation and distort the fibrils.


Assuntos
Flavonoides/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/antagonistas & inibidores , Ilhotas Pancreáticas/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Flavonoides/química , Frutas/química , Humanos , Células Secretoras de Insulina/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/síntese química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Ilhotas Pancreáticas/metabolismo , Simulação de Dinâmica Molecular , Substâncias Protetoras/síntese química , Substâncias Protetoras/química , Agregados Proteicos/efeitos dos fármacos , Syzygium/química
13.
Clin Transplant ; 35(1): e14138, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33131111

RESUMO

Early pancreas loss in simultaneous pancreas-kidney (SPK) transplants has been associated with longer perioperative recovery and reduced kidney allograft function. We assessed the impact of early pancreas allograft failure on transplant outcomes in a contemporary cohort of SPK patients (n = 218). Early pancreas allograft loss occurred in 12.8% (n = 28) of recipients. Delayed graft function (DGF) was more common (21.4% vs. 7.4%, p = 0.03) in the early pancreas loss group, but there were no differences in hospital length of stay (median 6.5 vs. 7.0, p = 0.22), surgical wound complications (p = 0.12), or rejection episodes occurring in the first year (p = 0.87). Despite differences in DGF, both groups had excellent renal function at 1 year post-transplant (eGFR 64.1 ± 20.8 vs. 65.8 ± 22.9, p = 0.75). There were no differences in patient (HR 0.58, 95% CI 0.18-1.87, p = 0.26) or kidney allograft survival (HR 0.84, 95% CI 0.23-3.06, p = 0.77). One- and 2-year protocol kidney biopsies were comparable between the groups and showed minimal chronic changes; the early pancreas loss group showed more cv changes at 2 years (p = 0.04). Current data demonstrate good outcomes and excellent kidney allograft function following early pancreas loss.


Assuntos
Transplante de Rim , Transplante de Pâncreas , Aloenxertos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Rim , Transplante de Rim/efeitos adversos , Pâncreas
14.
Mayo Clin Proc Innov Qual Outcomes ; 4(6): 657-666, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33367211

RESUMO

OBJECTIVES: To identify barriers to inpatient alteplase administration and implement an interdisciplinary program to reduce time to systemic thrombolysis. PATIENTS AND METHODS: Compared with patients presenting to the emergency department with an acute ischemic stroke (AIS), inpatients are delayed in receiving alteplase for systemic thrombolysis. Institutional AIS metrics were extracted from the electronic medical records of patients presenting as an inpatient stroke alert. All patients who received alteplase for AIS were included in the analysis. A gap analysis was used to assess institutional deficiencies. An interdisciplinary intervention was initiated to address these deficiencies. Efficacy was measured with pre- and postintervention surveys and institutional AIS metric analysis. Statistical significance was determined using the Student t test. We identified 5 patients (mean age, 73 years; 100% (5/5) male; 80% (4/5) white) who met inclusion criteria for the preintervention period (January 1, 2017, to December 31, 2017) and 10 patients (mean age, 71 years; 50% male; 80% white) for the postintervention period (October 31, 2018, to July 1, 2020). RESULTS: We found barriers to rapid delivery of thrombolytic treatment to include alteplase availability and comfort with bedside reconstitution. Interdisciplinary intervention strategies consisted of stocking alteplase on additional floors as well as structured education and hands-on alteplase reconstitution simulations for resident physicians. The mean time from stroke alert to thrombolysis was shorter postintervention than preintervention (57.4 minutes vs 77.8 minutes; P=.03). CONCLUSION: A coordinated interdisciplinary approach is effective in reducing time to systemic thrombolysis in patients experiencing AIS in the inpatient setting. A similar program could be implemented at other institutions to improve AIS treatment.

15.
Transl Res ; 220: 98-113, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32268128

RESUMO

The global burden of bacterial infections is rising due to increasing resistance to the majority of first-line antibiotics, rendering these drugs ineffective against several clinically important pathogens. Limited transport of antibiotics into cells compounds this problem for gram-negative bacteria that exhibit prominent intracellular lifecycles. Furthermore, poor bioavailability of antibiotics in infected tissues necessitates higher doses and longer treatment regimens to treat resistant infections. Although emerging antibiotics can combat these problems, resistance still may develop over time. Expanding knowledge of host-pathogen interactions has inspired research and development of host-directed therapies (HDTs). HDTs target host-cell machinery critical for bacterial pathogenesis to treat bacterial infections alone or as adjunctive treatment with traditional antibiotics. Unlike traditional antibiotics that directly affect bacteria, a majority of HDTs function by boosting the endogenous antimicrobial activity of cells and are consequently less prone to bacterial tolerance induced by selection pressure. Therefore, HDTs can be quite effective against intracellular cytosolic or vacuolar bacteria, which a majority of traditional antibiotics are unable to eradicate. However, in vivo therapeutic efficacy of HDTs is reliant on adequate bioavailability. Particle-based formulations demonstrate the potential to enable targeted drug delivery, enhance cellular uptake, and increase drug concentration in the host cell of HDTs. This review selected HDTs for clinically important pathogens, identifies formulation strategies that can improve their therapeutic efficacy and offers insights toward further development of HDTs for bacterial infections.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Farmacorresistência Bacteriana , Interações Hospedeiro-Patógeno , Humanos , Lipossomos , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química
16.
J Virol Methods ; 276: 113789, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31778677

RESUMO

Okra yellow vein mosaic disease (OYVMD) causes serious loss in okra production in Sri Lanka. Therefore, screening of resistant okra verities is an essential need to control the disease. As the available qualitative and semi-quantitative methods failed to detect latent infection the present study aimed to develop a quantitative PCR (qPCR) assay to detect and quantify one of the OYVMD causing agent, symptom modulating satellite molecules. A pair of primers targeting a portion of ßC1 gene of BYVMBs was designed and used to quantify of BYVMBs by absolute quantification method using SYBR Green I chemistry. Standard curves were prepared using series of dilutions of known copy number plasmids carrying target sequence. The mean amplification efficiency was 95% and the coefficient of determination was 0.994. The method was tested to find out the relation between symptoms and betasatellite titre in range of severity of OYVMD symptoms; the betasatellite titre increased with increasing severity. Interestingly, the method was able to detect BYVMBs present in apparently healthy plants growing in an infected field at a concentration which was not able to detect in end point PCR. Betasatellite titre was also measured in different ages of leaves and different positions. On average, the betasatellite titre in younger leaves was higher than in mature leaves and there were no significant variations in betasatellite titre in different position in each leaf. The assay was also tested as a tool to screen for resistant okra varieties; among the eight varieties tested no BYVMBs were detected in variety Maha F1. Varieties TV8 and MI5 had significantly higher copy number than rest of the varieties. The qPCR protocol described in this study is a useful method to detect and quantify BYVMBs in okra, especially for plant samples with betasatellite titre lower than the detection limit of conventional methods.


Assuntos
Abelmoschus/virologia , Begomovirus/genética , Begomovirus/isolamento & purificação , DNA Satélite/análise , Doenças das Plantas/virologia , Latência Viral/genética , DNA Satélite/genética , Folhas de Planta/virologia , Reação em Cadeia da Polimerase em Tempo Real
17.
J Mech Behav Biomed Mater ; 96: 204-213, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31054515

RESUMO

Current treatments for intervertebral disc degeneration and herniation are palliative only and cannot restore disc structure and function. Nucleus pulposus (NP) replacements are a promising strategy for restoring disc biomechanics and height loss. Cellulose-based hydrogel systems offer potential for NP replacement since they are stable, non-toxic, may be tuned to match NP material properties, and are conducive to cell or drug delivery. A crosslinked, carboxymethylcellulose-methylcellulose dual-polymer hydrogel was recently formulated as an injectable NP replacement that gelled in situ and restored disc height and compressive biomechanical properties. The objective of this study was to investigate the translational potential of this hydrogel system by examining the long-term structural stability in vitro, the herniation risk and fatigue bending endurance in a bovine motion segment model, and the in vivo biocompatibility in a rat subcutaneous pouch model. Results showed that the hydrogels maintained their structural integrity over a 12-week period. AF injury significantly increased herniation risk and reduced fatigue bending endurance in bovine motion segments. Samples repaired with cellulosic hydrogels demonstrated restored height and exhibited herniation risk and fatigue endurance comparable to samples that underwent the current standard treatment of nucleotomy. Lastly, injected hydrogels elicited a minimal foreign body response as determined by analysis of fibrous capsule development and macrophage presence over 12 weeks. Overall, this injectable cellulosic hydrogel system is a promising candidate as an NP substitute. Further assessment and optimization of this cellulosic hydrogel system in an in vivo intradiscal injury model may lead to an improved clinical solution for disc degeneration and herniation.


Assuntos
Celulose/química , Celulose/farmacologia , Hidrogéis/química , Deslocamento do Disco Intervertebral/prevenção & controle , Teste de Materiais , Núcleo Pulposo/efeitos dos fármacos , Animais , Bovinos , Injeções , Ratos , Medição de Risco , Estresse Mecânico
19.
Biochem J ; 476(5): 889-907, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30814273

RESUMO

The human islet amyloid polypeptide (hIAPP) or amylin is the major constituent of amyloidogenic aggregates found in pancreatic islets of type 2 diabetic patients that have been associated with ß-cell dysfunction and/or death associated with type 2 diabetes mellitus (T2DM). Therefore, developing and/or identifying inhibitors of hIAPP aggregation pathway and/or compound that can mediate disaggregation of preformed aggregates holds promise as a medical intervention for T2DM management. In the current study, the anti-amyloidogenic potential of Azadirachtin (AZD)-a secondary metabolite isolated from traditional medicinal plant Neem (Azadirachta indica)-was investigated by using a combination of biophysical and cellular assays. Our results indicate that AZD supplementation not only inhibits hIAPP aggregation but also disaggregates pre-existing hIAPP fibrils by forming amorphous aggregates that are non-toxic to pancreatic ß-cells. Furthermore, AZD supplementation in pancreatic ß-cells (INS-1E) resulted in inhibition of oxidative stress; along with restoration of the DNA damage, lipid peroxidation and the associated membrane damage, endoplasmic reticulum stress and mitochondrial membrane potential. AZD treatment also restored glucose-stimulated insulin secretion from pancreatic islets exposed to hIAPP. All-atom molecular dynamics simulation studies on full-length hIAPP pentamer with AZD suggested that AZD interacted with four possible binding sites in the amyloidogenic region of hIAPP. In summary, our results suggest AZD to be a promising candidate for combating T2DM and related amyloidogenic disorders.


Assuntos
Amiloide , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Limoninas/farmacologia , Simulação de Dinâmica Molecular , Estresse Oxidativo/efeitos dos fármacos , Amiloide/química , Amiloide/metabolismo , Amiloidose/tratamento farmacológico , Amiloidose/metabolismo , Amiloidose/patologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo
20.
Metabolomics ; 15(4): 55, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30927092

RESUMO

INTRODUCTION: Chronic exposure to high-glucose and free fatty acids (FFA) alone/or in combination; and the resulting gluco-, lipo- and glucolipo-toxic conditions, respectively, have been known to induce dysfunction and apoptosis of ß-cells in Diabetes. The molecular mechanisms and the development of biomarkers that can be used to predict similarities and differences behind these conditions would help in easier and earlier diagnosis of Diabetes. OBJECTIVES: This study aims to use metabolomics to gain insight into the mechanisms by which ß-cells respond to excess-nutrient stress and identify associated biomarkers. METHODS: INS-1E cells were cultured in high-glucose, palmitate alone/or in combination for 24 h to mimic gluco-, lipo- and glucolipo-toxic conditions, respectively. Biochemical and cellular experiments were performed to confirm the establishment of these conditions. To gain molecular insights, abundant metabolites were identified and quantified using 1H-NMR. RESULTS: No loss of cellular viability was observed in high-glucose while exposure to FFA alone/in combination with high-glucose was associated with increased ROS levels, membrane damage, lipid accumulation, and DNA double-strand breaks. Forty-nine abundant metabolites were identified and quantified using 1H-NMR. Chemometric pair-wise analysis in glucotoxic and lipotoxic conditions, when compared with glucolipotoxic conditions, revealed partial overlap in the dysregulated metabolites; however, the dysregulation was more significant under glucolipotoxic conditions. CONCLUSION: The current study compared gluco-, lipo- and glucolipotoxic conditions in parallel and elucidated differences in metabolic pathways that play major roles in Diabetes. o-phosphocholine and UDP-N-acetylglucosamine were identified as common dysregulated metabolites and their ratio was proposed as a potential biomarker for these conditions.


Assuntos
Células Secretoras de Insulina/metabolismo , Fosforilcolina/análise , Uridina Difosfato N-Acetilglicosamina/análise , Animais , Apoptose , Biomarcadores/sangue , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/metabolismo , Glucose/efeitos adversos , Glucose/metabolismo , Células Secretoras de Insulina/fisiologia , Palmitatos/efeitos adversos , Palmitatos/metabolismo , Fosforilcolina/sangue , Ratos , Uridina Difosfato N-Acetilglicosamina/sangue
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