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1.
Arch. argent. pediatr ; 122(1): e202303031, feb. 2024. ilus, tab
Artigo em Inglês, Espanhol | BINACIS, LILACS | ID: biblio-1525821

RESUMO

La espondiloencondrodisplasia con desregulación inmune relacionada a ACP5 (SPENCDI #607944, por la sigla de spondyloenchondrodysplasia with immune dysregulation y el número que le corresponde en OMIM, Online Mendelian Inheritance in Man) es una displasia inmuno-ósea poco frecuente con manifestaciones heterogéneas y gravedad variable. Presenta lesiones espondilometafisarias, disfunción inmune y compromiso neurológico. Se reportan aspectos clínicos, radiológicos y genéticos de cuatro niñas con SPENCDI en un hospital pediátrico. Todas presentaron manifestaciones esqueléticas y tres de ellas enfermedad inmunológica grave. Se encontró en tres pacientes la variante probablemente patogénica c.791T>A; p.Met264Lys en homocigosis, y en una paciente las variantes c.791T>A; p.Met264Lys y c.632T>C; p.lle211Thr (variante de significado incierto con predicción patogénica según algoritmos bioinformáticos) en heterocigosis compuesta en ACP5. La presencia de la variante repetida c.791T>A sugiere la posibilidad de un ancestro en común en nuestra población. El reconocimiento y diagnóstico de esta entidad es importante para lograr un oportuno abordaje, que deberá ser multidisciplinario, orientado hacia la prevención de posibles complicaciones.


Spondyloenchondrodysplasia with immune dysregulation related to ACP5 (SPENCDI, OMIM number 607944) is an uncommon immune-skeletal dysplasia with heterogeneous manifestations and variable severity. It is characterized by spondylar and metaphyseal lesions, immune dysfunction, and neurological involvement. Here we report the clinical, radiological and genetic aspects of 4 girls with SPENCDI treated at a children's hospital. They all had skeletal manifestations and 3 developed severe immune disease. In 3 patients, the likely pathogenic variant c.791T>A; p.Met264Lys (homozygous mutation) was observed, while 1 patient had variants c.791T>A; p.Met264Lys and c.632T>C; p.lle211Thr (variant of uncertain significance with pathogenic prediction based on bioinformatics algorithms) caused by a compound heterozygous mutation in ACP5. The repeated presence of variant c.791T>A suggests the possibility of a common ancestor in our population. The recognition and diagnosis of this disorder is important to achieve a timely approach, which should be multidisciplinary and aimed at preventing possible complications.


Assuntos
Humanos , Feminino , Pré-Escolar , Criança , Doenças Autoimunes , Síndromes de Imunodeficiência/complicações , Fosfatase Ácida Resistente a Tartarato/genética
2.
Arch Argent Pediatr ; 122(1): e202303031, 2024 02 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37382551

RESUMO

Spondyloenchondrodysplasia with immune dysregulation related to ACP5 (SPENCDI, OMIM number 607944) is an uncommon immune-skeletal dysplasia with heterogeneous manifestations and variable severity. It is characterized by spondylar and metaphyseal lesions, immune dysfunction, and neurological involvement. Here we report the clinical, radiological and genetic aspects of 4 girls with SPENCDI treated at a children's hospital. They all had skeletal manifestations and 3 developed severe immune disease. In 3 patients, the likely pathogenic variant c.791T>A; p.Met264Lys (homozygous mutation) was observed, while 1 patient had variants c.791T>A; p.Met264Lys and c.632T>C; p.lle211Thr (variant of uncertain significance with pathogenic prediction based on bioinformatics algorithms) caused by a compound heterozygous mutation in ACP5. The repeated presence of variant c.791T>A suggests the possibility of a common ancestor in our population. The recognition and diagnosis of this disorder is important to achieve a timely approach, which should be multidisciplinary and aimed at preventing possible complications.


La espondiloencondrodisplasia con desregulación inmune relacionada a ACP5 (SPENCDI #607944, por la sigla de spondyloenchondrodysplasia with immune dysregulation y el número que le corresponde en OMIM, Online Mendelian Inheritance in Man) es una displasia inmuno-ósea poco frecuente con manifestaciones heterogéneas y gravedad variable. Presenta lesiones espondilometafisarias, disfunción inmune y compromiso neurológico. Se reportan aspectos clínicos, radiológicos y genéticos de cuatro niñas con SPENCDI en un hospital pediátrico. Todas presentaron manifestaciones esqueléticas y tres de ellas enfermedad inmunológica grave. Se encontró en tres pacientes la variante probablemente patogénica c.791T>A; p.Met264Lys en homocigosis, y en una paciente las variantes c.791T>A; p.Met264Lys y c.632T>C; p.lle211Thr (variante de significado incierto con predicción patogénica según algoritmos bioinformáticos) en heterocigosis compuesta en ACP5. La presencia de la variante repetida c.791T>A sugiere la posibilidad de un ancestro en común en nuestra población. El reconocimiento y diagnóstico de esta entidad es importante para lograr un oportuno abordaje, que deberá ser multidisciplinario, orientado hacia la prevención de posibles complicaciones.


Assuntos
Doenças Autoimunes , Síndromes de Imunodeficiência , Criança , Feminino , Humanos , Fosfatase Ácida Resistente a Tartarato/genética , Síndromes de Imunodeficiência/complicações
3.
World Neurosurg ; 179: 177, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657589

RESUMO

Adamantinomatous craniopharyngioma (ACP) is a rare sellar region tumor seen in 0.5-2 cases per million persons each year,1 presenting a bimodal distribution that peaks at 5-15 years in children and 45-60 years in adults.2 Arising from embryonic remnants of the Rathke pouch epithelium, ACPs are associated with calcifications in 90% of cases and grow cranially toward the floor of the diencephalon.1 Craniopharyngiomas are benign but locally aggressive tumors, with microsurgery being the best chance of cure.3 The natural history is to compress the optic apparatus and hypothalamic-pituitary axis as they expand, with a propensity to encase the carotids. Endoscopic transbasal approaches have gained wide acceptance in the management of these tumors.4-6 However, open microsurgical approaches via pterional and orbitozygomatic craniotomies afford wider visualization of different corridors that help mitigate the surgical risks.7-9 The orbitozygomatic craniotomy allows lesions that extend above the optic chiasm to be safely approached from an inferior-to-superior corridor.9 The wide exposure of the basal arachnoid cisterns allows protection of the lenticulostriate perforators during resection.8-11 We demonstrate a step-by-step orbitozygomatic approach with dissection of the sylvian, carotid, carotid-oculomotor, chiasmatic, and lamina terminalis cisterns that allowed safe resection of a third ventricular ACP. The patient was a male in his 70s, who presented with progressive headaches and visual impairment. Magnetic resonance imaging showed a multicystic suprasellar lesion extending through the third ventricle. The surgery was performed with no complication (Video 1). Postoperative vision stabilized, and magnetic resonance imaging showed complete resection.


Assuntos
Craniofaringioma , Neoplasias Hipofisárias , Neoplasias da Base do Crânio , Adulto , Criança , Humanos , Masculino , Craniofaringioma/diagnóstico por imagem , Craniofaringioma/cirurgia , Craniofaringioma/patologia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/patologia , Craniotomia/métodos , Neoplasias da Base do Crânio/cirurgia , Microcirurgia
4.
Brain Sci ; 12(10)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36291220

RESUMO

Pimavanserin (PMV) is the first approved drug for treating hallucinations and delusions in Parkinson's disease (PD) psychosis. Psychosis is one of the leading causes of nursing home placement in people with PD. Furthermore, hallucinations are a more frequent cause of institutionalization than motor disability or dementia related to PD. The management of PD psychosis involves antipsychotic medications. Most of the drugs in this class directly block dopamine D2 receptors, leading to significantly worsening motor symptoms in patients with PD. The most commonly used medications for managing PD psychosis are quetiapine, clozapine, and PMV. This literature review aims to study pimavanserin's history, mechanism, clinical trials, and post-marketing experience. PMV is a potent 5-HT2A receptor antagonist/inverse agonist. Moreover, this drug can interact with 5-HT2C receptors. We calculated some physicochemical descriptors and pharmacokinetic properties of PMV. Eight clinical trials of PMV and PD psychosis are registered on ClinicalTrials.gov. Only four of them have complete results already published. Meta-analytic results showed that PMV efficacy is inferior to clozapine. However, PMV has a significantly lower number of side-effects for managing psychosis in PD. Medicare database assessment revealed 35% lower mortality with PMV compared to other atypical antipsychotics. Moreover, sensitive statistical analysis demonstrated that PMV is a protective factor for the risk of falls in individuals with PD.

5.
Front Microbiol ; 13: 961041, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992722

RESUMO

Serine palmitoyltransferase (SPT) catalyzes the first and committed step in sphingolipid biosynthesis condensating L-serine and acyl-CoA to form 3-oxo-sphinganine. Whenever the structural gene for SPT is present in genomes of Rhodobacteria (α-, ß-, and γ-Proteobacteria), it co-occurs with genes coding for a putative acyl carrier protein (ACP) and a putative acyl-CoA synthetase (ACS). In the α-proteobacterium Caulobacter crescentus, CC_1162 encodes an SPT, whereas CC_1163 and CC_1165 encode the putative ACP and ACS, respectively, and all three genes are known to be required for the formation of the sphingolipid intermediate 3-oxo-sphinganine. Here we show that the putative ACP possesses a 4'-phosphopantetheine prosthetic group, is selectively acylated by the putative ACS and therefore is a specialized ACP (AcpR) required for sphingolipid biosynthesis in Rhodobacteria. The putative ACS is unable to acylate coenzyme A or housekeeping ACPs, but acylates specifically AcpR. Therefore, it is a specialized acyl-ACP synthetase (AasR). SPTs from C. crescentus, Escherichia coli B, or Sphingomonas wittichii use preferentially acyl-AcpR as thioester substrate for 3-oxo-sphinganine synthesis. Whereas acyl-AcpR from C. crescentus is a good substrate for SPTs from distinct Rhodobacteria, acylation of a specific AcpR is achieved by the cognate AasR from the same bacterium. Rhodobacteria might use this more complex way of 3-oxo-sphinganine formation in order to direct free fatty acids toward sphingolipid biosynthesis.

6.
Bioorg Chem ; 127: 106000, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35853296

RESUMO

In the last decade, emerging evidence has shown that low molecular weight protein tyrosine phosphatase (LMWPTP) not only contributes to the progression of cancer but is associated with prostate low survival rate and colorectal cancer metastasis. We report that LMWPTP favors the glycolytic profile in some tumors. Therefore, the focus of the present study was to identify metabolic enzymes that correlate with LMWPTP expression in patient samples. Exploratory data analysis from RNA-seq, proteomics, and histology staining, confirmed the higher expression of LMWPTP in CRC. Our descriptive statistical analyses indicate a positive expression correlation between LMWPTP and energy metabolism enzymes such as acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN). In addition, we examine the potential of violacein to reprogram energetic metabolism and LMWPTP activity. Violacein treatment induced a shift of glycolytic to oxidative metabolism associated with alteration in mitochondrial efficiency, as indicated by higher oxygen consumption rate. Particularly, violacein treated cells displayed higher proton leak and ATP-linked oxygen consumption rate (OCR) as an indicator of the OXPHOS preference. Notably, violacein is able to bind and inhibit LMWPTP. Since the LMWPTP acts as a hub of signaling pathways that offer tumor cells invasive advantages, such as survival and the ability to migrate, our findings highlight an unexplored potential of violacein in circumventing the metabolic plasticity of tumor cells.


Assuntos
Neoplasias Colorretais , Proteínas Tirosina Fosfatases , Neoplasias Colorretais/patologia , Humanos , Indóis , Masculino , Mitocôndrias/metabolismo , Peso Molecular , Proteínas Tirosina Fosfatases/metabolismo , Tirosina
7.
Lasers Med Sci ; 37(3): 1583-1592, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34767116

RESUMO

A bone scaffold added to the dental alveolus immediately after an extraction avoids bone atrophy and deformity at the tooth loss site, enabling rehabilitation with implants. Photobiomodulation accelerates bone healing by stimulating blood flow, activating osteoblasts, diminishing osteoclastic activity, and improving the integration of the biomaterial with the bone tissue. The aim of the present study was to evaluate the effect of photobiomodulation with LED at a wavelength of 850 nm on bone quality in Wistar rats submitted to molar extraction with and without a bone graft using hydroxyapatite biomaterial (Straumann® Cerabone®). Forty-eight rats were distributed among five groups (n = 12): basal (no interventions); control (extraction) (basal and control were the same animal, but at different sides); LED (extraction + LED λ = 850 nm); biomaterial (extraction + biomaterial), and biomaterial + LED (extraction + biomaterial + LED λ = 850 nm). Euthanasia occurred at 15 and 30 days after the induction of the extraction. The ALP analysis revealed an improvement in bone formation in the control and biomaterial + LED groups at 15 days (p = 0.0086 and p = 0.0379, Bonferroni). Moreover, the LED group had better bone formation compared to the other groups at 30 days (p = 0.0007, Bonferroni). In the analysis of AcP, all groups had less resorption compared to the basal group. Bone volume increased in the biomaterial, biomaterial + LED, and basal groups in comparison to the control group at 15 days (p < 0.05, t-test). At 30 days, the basal group had greater volume compared to the control and LED groups (p < 0.05, t-test). LED combined with the biomaterial improved bone formation in the histological analysis and diminished bone degeneration (demonstrated by the reduction in AcP), promoting an increase in bone density and volume. LED may be an important therapy to combine with biomaterials to promote bone formation, along with the other known benefits of this therapy, such as the control of pain and the inflammatory process.


Assuntos
Materiais Biocompatíveis , Terapia com Luz de Baixa Intensidade , Animais , Materiais Biocompatíveis/farmacologia , Durapatita , Ratos , Ratos Wistar , Extração Dentária , Alvéolo Dental/patologia
8.
Biochim Biophys Acta Mol Basis Dis ; 1868(1): 166280, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610471

RESUMO

Over the last decades, some members of the protein tyrosine phosphatase family have emerged as cancer promoters. Among them, the Low Molecular Weight Protein Tyrosine Phosphatase (LMWPTP) has been described to be associated with colorectal cancer liver metastasis and poor prostate cancer prognosis. Of importance in the process of cancer progression and metastasis is the interaction between tumor cells and platelets, as the latter are thought to promote several tumor hallmarks. Here, we examine to what extent LMWPTP expression in tumor cells affects their interaction with platelets. We demonstrate that the gene encoding LMWPTP is overexpressed in upper gastrointestinal (GI) cancer cell as well as colorectal cancer, and subsequently employ cell line models to show that the level of this phosphatase may be further augmented in the presence of platelets. We demonstrate that tumor-platelet interaction promotes GI tumor cell proliferation. Additionally, using know-down/-out models we show that LMWPTP expression in cancer cells contributes to a more efficient interaction with platelets and drives platelet-induced proliferation. These data are the first to demonstrate that phosphatases play a positive role in the tumor-promoting activities of platelets, with LMWPTP emerging as a key player promoting oncogenic phenotypic changes in tumor cells.


Assuntos
Plaquetas/metabolismo , Carcinogênese/genética , Neoplasias Gastrointestinais/genética , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas/genética , Plaquetas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Técnicas de Cocultura , Feminino , Neoplasias Gastrointestinais/patologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Peso Molecular , Metástase Neoplásica , Transdução de Sinais/genética , Microambiente Tumoral/genética
9.
J Biomol Struct Dyn ; 40(14): 6295-6307, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33554762

RESUMO

Malaria is a disease caused by Plasmodium genus. which P. falciparum is responsible for the most severe form of the disease, cerebral malaria. In 2018, 405,000 people died of malaria. Antimalarial drugs have serious adverse effects and limited efficacy due to multidrug-resistant strains. One way to overcome these limitations is the use of computational approaches for prioritizing candidates to phenotypic assays and/or in vitro assays against validated targets. Plasmodium falciparum Enoyl-ACP reductase (PfENR) is noteworthy because it catalyzes the rate-limiting step of the biosynthetic pathway of fatty acid. Thus, the study aimed to identify potential PfENR inhibitors by ligand (2D molecular similarity and pharmacophore models) and structure-based virtual screening (molecular docking). 2D similarity-based virtual screening using Tanimoto Index (> 0.45) selected 29,236 molecules from natural products subset available in ZINC database (n = 181,603). Next, 10 pharmacophore models for PfENR inhibitors were generated and evaluated based on the internal statistical parameters from GALAHAD™ and ROC/AUC curve. These parameters selected a suitable pharmacophore model with one hydrophobic center and two hydrogen bond acceptors. The alignment of the filtered molecules on best pharmacophore model resulted in the selection of 10,977 molecules. These molecules were directed to the docking-based virtual screening by AutoDock Vina 1.1.2 program. These strategies selected one compound to phenotypic assays against parasite. ZINC630259 showed EC50 = 0.12 ± 0.018 µM in antiplasmodial assays and selective index similar to other antimalarial drugs. Finally, MM/PBSA method showed stability of molecule within PfENR binding site (ΔGbinding=-57.337 kJ/mol).Communicated by Ramaswamy H. Sarma.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Antimaláricos/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/metabolismo , Inibidores Enzimáticos/química , Humanos , Malária/tratamento farmacológico , Simulação de Acoplamento Molecular , Plasmodium falciparum
10.
Front Microbiol ; 12: 687725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34322103

RESUMO

The Asian citrus psyllid, Diaphorina citri, is the vector of the bacterium "Candidatus Liberibacter asiaticus" (Las), associated with the devastating, worldwide citrus disease huanglongbing. In order to explore the molecular interactions of this bacterium with D. citri during the vector acquisition process, cDNA libraries were sequenced on an Illumina platform, obtained from the gut of adult psyllids confined in healthy (H) and in Las-infected young shoots (Las) for different periods of times (I = 1/2 days, II = 3/4 days, and III = 5/6 days). In each sampling time, three biological replicates were collected, containing 100 guts each, totaling 18 libraries depleted in ribosomal RNA. Reads were quality-filtered and mapped against the Chinese JXGC Las strain and the Floridian strain UF506 for the analysis of the activity of Las genome and SC1, SC2, and type 3 (P-JXGC-3) prophages of the studied Las strain. Gene activity was considered only if reads of at least two replicates for each acquisition access period mapped against the selected genomes, which resulted in coverages of 44.4, 79.9, and 94.5% of the JXGC predicted coding sequences in Las I, Las II, and Las III, respectively. These genes indicate an active metabolism and increased expression according to the feeding time in the following functional categories: energy production, amino acid metabolism, signal translation, cell wall, and replication and repair of genetic material. Pilins were among the most highly expressed genes regardless of the acquisition time, while only a few genes from cluster I of flagella were not expressed. Furthermore, the prophage region had a greater coverage of reads for SC1 and P-JXGC-3 prophages and low coverage in SC2 and no indication of activity for the lysis cycle. This research presents the first descriptive analysis of Las transcriptome in the initial steps of the D. citri gut colonization, where 95% of Las genes were active.

11.
J Biomol Struct Dyn ; 39(9): 3378-3386, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32364060

RESUMO

Malaria is an infectious disease caused by protozoa of the genus Plasmodium spp. with approximately 219 million cases in 2017. P. falciparum is main responsible for the most severe form of the disease, cerebral malaria. Despite of public health impacts, chemotherapy against malaria is still limited due to the emergence of drug resistance cases used in monotherapy and combination therapies. Thus, the development of new antimalarial drugs becomes emergency. One way of achieve this goal is to explore essential and/or unique therapeutic targets of the parasite, or at least sufficiently different to ensure selective inhibition. Enoil-ACP reductase (ENR) is a NADH-dependent enzyme responsible for the limiting step of the type II fatty acid biosynthetic pathway (FAS II). Thus, pharmacophore and docking based virtual screening were applied to prioritize molecules for in vitro assays against P. falciparum W2 strain. The application of successive filters at OOCC database (n = 618) resulted in the identification of one molecule (13) (EC50 = 0.098 ± 0.021 µM) with similar biological activity to artemether. The molecule 13 is a typical drug repurposing case due to previous other approved therapeutic uses on Chinese medicine as a non-specific cholinergic antagonist, thus it could be accelerated the drug development process. Additionally, molecular dynamics studies were used to confirm stability of the molecular interactions identified by molecular docking. Thus, representative structures of P. falciparum ENR can be used in a study to propose new derivatives for evaluation of biological activity in vitro and in vivo. Communicated by Ramaswamy H. Sarma.


Assuntos
Antimaláricos , Malária Falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Humanos , Malária Falciparum/tratamento farmacológico , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Plasmodium falciparum
12.
Arch Oral Biol ; 122: 105001, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33316658

RESUMO

OBJECTIVE: To evaluate the effects of combination of treatments with fluoridated toothpastes supplemented with sodium trimetaphosphate (TMP) and casein phosphopeptide-amorphous calcium phosphate (MI Paste Plus®), on the remineralization of dental enamel. DESIGN: Enamel blocks with artificial caries were randomly allocated into six groups (n = 12), according to the toothpastes: 1) without F-TMP-MI Paste Plus® (Placebo); 2) 1100 ppm F (1100 F), 3) MI Paste Plus®, 4) 1100 F + MI Paste Plus® (1100 F-MI Paste Plus®), 5) 1100 F + 3% TMP (1100 F-TMP) and 6) 1100 F-TMP + MI Paste Plus® (1100 F-TMP-MI Paste Plus®). Blocks were treated 2×/day with slurries of toothpastes (1 min). Furthermore, groups 4 and 6 received the application of MI Paste Plus® for 3 min. After pH cycling, the percentage of surface hardness recovery (%SHR); integrated loss of subsurface hardness (ΔKHN); profile analysis and lesion depth subsurface through polarized light microscopy (PLM), confocal laser scanning microscopy (LSCM), scanning electron microscopy (SEM), fluoride (F), calcium (Ca), phosphorus (P) concentrations in the enamel were determined. The data were analyzed by ANOVA (1-criterion) and Student-Newman-Keuls test (p < 0.001). RESULTS: 1100 F-TMP-MI Paste Plus® group showed the best results of %SHR, ΔKHN and PLM (p < 0.001). F concentration was similar between the 1100 F, 1100 F-MI Paste Plus®, and 1100 F-TMP-MI Paste Plus® groups (p > 0.001). 1100 F-TMP-MI Paste Plus® group showed the highest concentration of Ca and P in the enamel (p < 0.001). CONCLUSION: The association of 1100 F-TMP and MI Paste Plus® led to a significant increase in the remineralization of initial carious lesions.


Assuntos
Fosfatos de Cálcio/farmacologia , Cariostáticos/farmacologia , Esmalte Dentário/efeitos dos fármacos , Fluoretos/farmacologia , Polifosfatos/farmacologia , Remineralização Dentária , Caseínas/farmacologia , Cárie Dentária/tratamento farmacológico , Humanos , Técnicas In Vitro , Fosfopeptídeos/farmacologia , Distribuição Aleatória , Cremes Dentais/farmacologia
13.
Mol Microbiol ; 114(4): 653-663, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32671874

RESUMO

A key aspect in membrane biogenesis is the coordination of fatty acid to phospholipid synthesis rates. In most bacteria, PlsX is the first enzyme of the phosphatidic acid synthesis pathway, the common precursor of all phospholipids. Previously, we proposed that PlsX is a key regulatory point that synchronizes the fatty acid synthase II with phospholipid synthesis in Bacillus subtilis. However, understanding the basis of such coordination mechanism remained a challenge in Gram-positive bacteria. Here, we show that the inhibition of fatty acid and phospholipid synthesis caused by PlsX depletion leads to the accumulation of long-chain acyl-ACPs, the end products of the fatty acid synthase II. Hydrolysis of the acyl-ACP pool by heterologous expression of a cytosolic thioesterase relieves the inhibition of fatty acid synthesis, indicating that acyl-ACPs are feedback inhibitors of this metabolic route. Unexpectedly, inactivation of PlsX triggers a large increase of malonyl-CoA leading to induction of the fap regulon. This finding discards the hypothesis, proposed for B. subtilis and extended to other Gram-positive bacteria, that acyl-ACPs are feedback inhibitors of the acetyl-CoA carboxylase. Finally, we propose that the continuous production of malonyl-CoA during phospholipid synthesis inhibition provides an additional mechanism for fine-tuning the coupling between phospholipid and fatty acid production in bacteria with FapR regulation.


Assuntos
Bacillus subtilis/metabolismo , Ácidos Graxos/biossíntese , Fosfolipídeos/biossíntese , Proteína de Transporte de Acila/metabolismo , Proteínas de Bactérias/metabolismo , Ácidos Graxos/metabolismo , Lipogênese , Fosfolipídeos/metabolismo , Regulon
14.
Parasitol Res ; 119(6): 1879-1887, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32382989

RESUMO

Malaria, caused by protozoa of the genus Plasmodium, is a disease that infects hundreds of millions of people annually, causing an enormous social burden in many developing countries. Since current antimalarial drugs are starting to face resistance by the parasite, the development of new therapeutic options has been prompted. The enzyme Plasmodium falciparum enoyl-ACP reductase (PfENR) has a determinant role in the fatty acid biosynthesis of this parasite and is absent in humans, making it an ideal target for new antimalarial drugs. In this sense, the present study aimed at evaluating the in silico binding affinity of natural and synthetic amides through molecular docking, in addition to their in vitro activity against P. falciparum by means of the SYBR Green Fluorescence Assay. The in vitro results revealed that the natural amide piplartine (1a) presented partial antiplasmodial activity (20.54 µM), whereas its synthetic derivatives (1m-IC50 104.45 µM), (1b, 1g, 1k, and 14f) and the natural amide piperine (18a) were shown to be inactive (IC50 > 200 µM). The in silico physicochemical analyses demonstrated that compounds 1m and 14f violated the Lipinski's rule of five. The in silico analyses showed that 14f presented the best binding affinity (- 13.047 kcal/mol) to PfENR and was also superior to the reference inhibitor triclosan (- 7.806 kcal/mol). In conclusion, we found that the structural modifications in 1a caused a significant decrease in antiplasmodial activity. Therefore, new modifications are encouraged in order to improve the activity observed.


Assuntos
Amidas/farmacologia , Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Amidas/química , Animais , Chlorocebus aethiops , Simulação por Computador , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/antagonistas & inibidores , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/metabolismo , Células Hep G2 , Humanos , Malária Falciparum , Simulação de Acoplamento Molecular , Piper nigrum , Plasmodium falciparum/enzimologia , Triclosan/farmacologia , Células Vero
15.
Mol Cell Biochem ; 466(1-2): 83-89, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016696

RESUMO

In the last decade, several reports highlight the importance of the low molecular weight protein tyrosine phosphatase (LMWPTP) in cancer aggressiveness and resistance. Specifically, in chronic myeloid leukemia, we have reported that high expression of the LMWPTP maintains Src and Bcr-Abl kinases in an activated status and the glucose metabolism is directed to lactate production and, in turn, favor the pentoses pathway (one of the key process for antioxidant and protective responses). In this present study, we investigated the possible correlation between the LMWPTP and autophagy. In resistant chronic myeloid leukemia cells, the antioxidant response is supported by the glycolytic metabolism and antioxidant enzymes such as SOD and catalase, both favored by the LMWPTP. Therefore, when the cells were challenged by hydrogen peroxide treatment, the LMWPTP level goes down as well as SOD, and in turn, autophagy process was stimulated. The findings presented here reveal a novel aspect by which LMWPTP cooperates for the resistance of CML towards stressor stimuli.


Assuntos
Antioxidantes/metabolismo , Autofagia , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia
16.
Acta sci. vet. (Impr.) ; 48: Pub.1740-Jan. 30, 2020. ilus, tab
Artigo em Português | VETINDEX | ID: biblio-1458263

RESUMO

Background: Sperm sexing is increasing in use because pre-determining the sex of the calf allows greater profitability and promotes significant gains in the productive systems that utilize the technique. Deployment of a low-cost and practical preservation methodol-ogy may further favor the cost-benefit ratio. Flow cytometry, the most commonly used sexing technique, has high costs and is very restricted. As an alternative, immunosexing has been studied, which uses sex-specific monoclonal antibodies. Thus, the objective of this study was to evaluate the immunosexing technique in conjunction with cryopreservation in ACP-102c and examine its economic aspects with regard to ram semen.Materials, Methods & Results: Ejaculates from two ram individuals were collected with the aid of an artificial vagina, evaluated, and submitted to the immunosexing protocol, according to the manufacturer’s recommendations, using the Monoclonal Antibody Kit specific for mammalian sperm with “Y” chromosomes (HY; HY Biotechnology, Rio de Janeiro-RJ, Brazil). After sexing, the supernatant was resuspended in the cryopreservation diluent: ACP (ACP-102c + 20% egg yolk + 7% glycerol), packaged in 0.25 mL straws, refrigerated to 4°C, stabilized for 30 min, frozen in liquid nitrogen vapors (-60°C) for 15 min, immersed in liquid nitrogen, and stored in cryogenic cylinders. The samples were thawed and evaluated for sperm kinetics both by using computerized semen analysis with SCA® software (Sperm Class Analyzer version 5.0) and subjectively comparing specimens from the two animals using conventional microscopy (40x). Plasma membrane integrity (IMP) and sperm cell morphology were evaluated by the smear staining technique...


Assuntos
Animais , Alimentos de Coco , Criopreservação/veterinária , Espermatozoides , Ovinos , Preservação do Sêmen/economia , Preservação do Sêmen/veterinária , Cocos , Custos e Análise de Custo
17.
Clin Oral Investig ; 24(3): 1299-1309, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31302769

RESUMO

OBJECTIVES: MI Paste Plus remineralizer (Rem) strengthens dental structures after bleaching. We investigated the effect of Rem on the penetration of hydrogen peroxide (H2O2), bleaching effectiveness, and pulp inflammation after bleaching. MATERIALS AND METHODS: Bovine disks were grouped as follows (n = 10): control (untreated), bleached (Ble; 35% H2O2, 30 min), Ble-Rem (H2O2 followed by Rem, 30 min), Rem-Ble (Rem followed by H2O2), Rem-Ble-Rem (Rem before and after H2O2), and Ble+Rem (mixture of Rem with H2O2, 1:1, 30 min). The penetration of H2O2 was quantified and bleaching efficacy was analyzed. Upper rat molars (n = 10) received the same treatments at random. The rats were euthanized after two days and 30 days, and their jaws were removed for histological analysis. Statistical tests were performed (P < 0.05). RESULTS: The bleached groups, except Ble+Rem (P > 0.05), showed significant H2O2 penetration compared with control (P < 0.05). Color alteration analysis showed that ΔL and ΔE were significantly higher in the bleached groups than those in control (P < 0.05); the Δb of the bleached groups differed from that of control at 24 h (P < 0.05). At two days, necrosis or inflammation was observed in the bleached groups compared with control (P < 0.05), except Ble+Rem, which was similar to control (P > 0.05). At 30 days, tertiary dentin formation was significant in the bleached groups (P < 0.05), except Ble+Rem (P > 0.05). CONCLUSION: The mixture of MI Paste Plus and bleaching gel reduces H2O2 penetration and pulp damage and maintains bleaching effectiveness. CLINICAL RELEVANCE: Because bleaching can damage dental tissues, we studied a new bleaching protocol that reduces damage to the pulp tissue while maintaining bleaching efficiency: a single application of 30 min of MI Paste Plus mixed with 35% H2O2 bleaching gel (1:1).


Assuntos
Polpa Dentária/efeitos dos fármacos , Peróxido de Hidrogênio , Clareadores Dentários , Clareamento Dental , Animais , Bovinos , Géis , Masculino , Ratos , Ratos Wistar
18.
Cryobiology ; 92: 53-61, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31704199

RESUMO

Due to the global decrease in jaguar population, conservation strategies are essential and the development of effective semen cryopreservation protocols would contribute to the formation of germplasm banks. Therefore, the objectives were to (1) evaluate the use of TRIS and ACP-117c extenders for jaguar semen freezing, (2) describe the ultrastructural changes in sperm after cryopreservation, and (3) evaluate the binding capacity of the thawed sperm. Eight ejaculates from five mature individuals were collected by electroejaculation, extended in TRIS or a coconut based-extender (ACP-117c), and frozen in liquid nitrogen. Samples were evaluated for sperm motility, vigor, membrane functionality, mitochondrial activity, morphology (using light microscopy, scanning electron microscopy - SEM and transmission electron microscopy - TEM), sperm kinetic parameters (by computerized analysis - CASA), and sperm binding capability using an egg yolk perivitelline membrane assay. Samples preserved in TRIS presented better post-thaw motility (46.0 ±â€¯7.7%) and membrane functionality (60.5 ±â€¯4.2%) and higher mitochondrial activity (21.5 ±â€¯3.7%) than those preserved in ACP-117c (20.9 ±â€¯5.4% motile sperm; 47.1 ±â€¯2.5% functional membrane; 11.8 ±â€¯1.7% mitochondrial activity). Regarding ultrastructural evaluations, SEM showed that both extenders were able to preserve the superficial membrane of the sperm, but TEM revealed the occurrence of nuclear electron lucent points, especially in samples extended in ACP-117c. Additionally, TRIS also provided a higher number of sperm bound to the perivitelline membrane (29.5 ±â€¯3.3%) in comparison to samples diluted in ACP-117c (18.6 ±â€¯1.5%). Overall, we suggest the use of a TRIS-based extender for cryopreservation of jaguar semen.


Assuntos
Crioprotetores/farmacologia , Panthera/embriologia , Preservação do Sêmen/métodos , Espermatozoides/ultraestrutura , Trometamina/farmacologia , Animais , Cocos/química , Criopreservação/métodos , Crioprotetores/química , Gema de Ovo/química , Congelamento , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Sêmen/fisiologia , Análise do Sêmen , Motilidade dos Espermatozoides
19.
Araçatuba; s.n; 2020. 100 p. ilus, tab, graf.
Tese em Português | BBO - Odontologia, LILACS | ID: biblio-1392323

RESUMO

A proposição geral do presente estudo foi avaliar in vitro a associação de tratamentos com dentifrícios fluoretados e suplementados com trimetafosfato de sódio (TMP) e fosfopeptídeo de caseína-fosfato de cálcio amorfo (CPP-ACP) (MI Paste Plus®) em promover a remineralização e reduzir a desmineralização, respectivamente, do esmalte dentário. Blocos de esmalte bovinos (12/grupo) foram selecionados através da dureza de superfície inical (SH) e divididos em 5 grupos experimentais: 1) Dentifrício sem F (Placebo); 2) Dentifrício com 1100 ppm F (1100F), 3) MI Paste Plus®, 4) Dentifrício com 1100 ppm F associado a MI Paste Plus® (1100F-MI Paste Plus®) e 5) Dentifrício com 1100 ppm F + 3%TMP associado a MI Paste Plus® (1100F-TMPMI Paste Plus®). Para o Artigo 1 de Remineralização (RE>DES), blocos de esmalte bovino foram selecionados pela dureza de superfície pós-lesão de cárie artificial (SH1) e submetidos a 6 ciclagens de pH por 6 dias. Após as ciclagens de pH, foram determinadas dureza de superfície final (SH2), para o cálculo da porcentagem de recuperação de dureza de superfície (%SHR), perda integrada de dureza de subsuperfície (ΔKHN), análise do perfil e profundidade das lesões de subsuperfície através da microscopia de luz polarizada (PLM), microsopia confocal de varredura à laser (MCVL), microscopia eletrônica de varredura (MEV), espectroscopia de energia dispersiva (EDS), concentração de fluoreto (F), cálcio (Ca) e fósforo (P) no esmalte. Os dados foram submetidos à ANOVA (1-critério), seguido pelo teste StudentNewman-Keuls (p < 0,001). Os grupos 1100F e 1100F-TMP-MI Paste Plus® apresentaram valores semelhantes de %SHR (p = 0,150). A menor profundidade de lesão (ΔKHN e PLM) foi observada para o grupo 1100F-TMP-MI Paste Plus® quando comparado aos demais (p < 0,001). O grupo 1100F-TMP-MI Paste Plus® apresentou superfície mais uniforme e íntegra em relação aos demais tratamentos (MCVL e MEV). A concentração de F foi similar entre os grupos 1100F, 1100F-MI Paste Plus® e 1100F-TMP-MI Paste Plus® (p > 0,001). O tratamento com 1100F-TMP-MI Paste Plus® promoveu um aumento na concentração de Ca no esmalte em ⁓ 51% e ⁓ 21% respectivamente, quando comparado aos grupos 1100F e MI Paste Plus® (p < 0,001). Valores semelhantes de P no esmalte foram observados nos grupos MI Paste Plus®, 1100F-MI Paste Plus® (p > 0,001), exceto o grupo 1100F-TMP-MI Paste Plus®, que apresentou alta concentração (p < 0,001). Para o Artigo 2 de Desmineralização (DES>RE), blocos de esmalte bovino foram selecionados pela dureza de superfície inicial (SHi) e a seguir submetidos a 5 ciclagens de pH por 7 dias. Após determinou-se dureza de superfície final (SHf), porcentagem de perda de dureza de superfície (%SH), perda integrada de dureza de subsuperfície (ΔKHN), análise do perfil e profundidade das lesões de subsuperfície através da microscopia de luz polarizada (PLM), microsopia confocal de varredura à laser (MCVL), microscopia eletrônica de varredura (MEV), espectroscopia de energia dispersiva (EDS), concentração de fluoreto (F), cálcio (Ca) e fósforo (P) no esmalte. Os dados foram submetidos à ANOVA (1-critério), seguido pelo teste Student-Newman-Keuls (p < 0,001). Para a %SHR, o grupo Placebo apresentou os menores valores (p > 0,001). O grupo 1100F-TMP-MI Paste Plus® remineralizou a superfície do esmalte em ~ 38% em relação ao MI Paste Plus® (p < 0,001). A menor profundidade da lesão (ΔKHN) foi observada para o grupo 1100F-TMP-MI Paste Plus® quando comparado aos demais (p < 0,001), sendo inferior em 32% quando comparado ao grupo 1100F. A concentração de F, Ca e P foi maior para o grupo 1100F-TMP-MI Paste Plus® (p > 0,001). Diante dos resultados parciais obtidos, é possível concluir que a associação de tratamentos com dentifrícios fluoretados e suplementados com trimetafosfato de sódio (TMP) e fosfopeptídeo de caseína-fosfato de cálcio amorfo (CPP-ACP) (MI Paste Plus®) (1100F-TMPMI Paste Plus®) promoveu um efeito adicional significativo no processo de desremineralização, podendo ser uma alternativa de tratamento para pacientes em risco e atividade de cárie(AU)


The general purpose of this study was to evaluate in vitro the association of treatments with fluoridated toothpastes and supplemented with sodium trimetaphosphate (TMP) and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) (MI Paste Plus®) in promoting remineralization and reduce demineralization, respectively, of tooth enamel. Bovine enamel blocks (12/group) were selected through the initial surface hardness (SH) and divided into 5 experimental groups: 1) Toothpaste without F (Placebo); 2) Toothpaste with 1100 ppm F (1100F), 3) MI Paste Plus®, 4) Toothpaste with 1100 ppm F associated with MI Paste Plus® (1100F-MI Paste Plus®) and 5) Toothpaste with 1100 ppm F + 3% TMP associated with MI Paste Plus® (1100F-TMP-MI Paste Plus®). For Remineralization Manuscript 1 (RE>DES), blocks of bovine enamel were selected for the surface hardness after artificial caries lesion (SH1) and subjected to 6 pH cycles for 6 days. After pH cycling, final surface hardness (SH2) was determined to calculate the percentage of surface hardness recovery (%SHR), integrated loss of subsurface hardness (ΔKHN), profile analysis and depth of the lesions of subsurface through polarized light microscopy (PLM), confocal laser scanning microscope (MCVL), scanning electron microscopy (SEM), dispersive energy spectroscopy (EDS), fluoride (F), calcium (Ca) and phosphorus (P) concentration in the enamel. The data were submitted to ANOVA (1-criterion), followed by the Student-Newman-Keuls test (p<0.001). 1100F and 1100F-TMP-MI Paste Plus® groups showed similar values of %SHR (p = 0.150). The lowest depth of lesion (ΔKHN and PLM) was observed for the 1100F-TMP-MI Paste Plus® group when compared to the others (p<0.001). The 1100F-TMP-MI Paste Plus® group showed a more uniform and complete surface in relation to the other treatments (MCVL and SEM). The F concentration was similar between the 1100F, 1100F-MI Paste Plus® and 1100F-TMP-MI Paste Plus® groups (p>0.001). The treatment with 1100F-TMP-MI Paste Plus® promoted an increase in the concentration of Ca in the enamel by ⁓ 51% and ⁓ 21% respectively, when compared to the 1100F and MI Paste Plus® groups (p<0.001). Similar values of P in the enamel were observed in the MI Paste Plus®, 1100F-MI Paste Plus® groups (p>0.001), except for the 1100F-TMP-MI Paste Plus® group, which presented high concentration (p<0.001). For demineralization Manuscript 2 (DES> RE), bovine of enamel blocks were selected for their initial surface hardness (SHi) and then subjected to 5 pH cycles for 7 days. After final surface hardness (SHf), percentage of loss of surface hardness (%SH), integrated loss of subsurface hardness (ΔKHN), analysis of the profile and depth of subsurface lesions through polarized light microscopy ( PLM), confocal laser scanning microscopy (MCVL), scanning electron microscopy (SEM), dispersive energy spectroscopy (EDS), fluoride (F), calcium (Ca) and phosphorus (P) concentration in the enamel. The data were submitted to ANOVA (1-criterion), followed by the Student-Newman-Keuls test (p<0.001). For %SHR, the Placebo group had the lowest values (p>0.001). The 1100F-TMP-MI Paste Plus® group remineralized the enamel surface by ~ 38% compared to MI Paste Plus® (p<0.001). The lowest depth of the lesion (ΔKHN) was observed for the 1100F-TMP-MI Paste Plus® group when compared to the others (p<0.001), being 32% lower when compared to the 1100F group. The F, Ca and P concentration was higher for the 1100F-TMP-MI Paste Plus® group (p>0.001). In view of the partial results obtained, it is possible to conclude that the combination of treatments with fluoridated toothpastes and supplemented with sodium trimetaphosphate (TMP) and amorphous calcium phosphate casein-phosphate (CPP-ACP) (MI Paste Plus®) (1100F-TMP -MI Paste Plus®) promoted a significant additional effect in the de-remineralization process, and could be an alternative treatment for patients at risk and caries activity(AU)


Assuntos
Fosfatos , Remineralização Dentária , Desmineralização , Esmalte Dentário , Fluoretos , Cremes Dentais , Cárie Dentária , Dentifrícios
20.
Rev. peru. biol. (Impr.) ; 26(4): 503-508, Oct.-Dec 2019. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1144916

RESUMO

Proctoporus machupicchu es una especie de lagartija semifosorial que fue descubierta en dos localidades dentro del Santuario Histórico de Machu Picchu (SHMP), Cusco, Perú. La serie tipo está conformada por dos hembras y un macho, sin embargo, el paratipo macho no posee poros femorales lo cual es incongruente con los machos mencionados en la literatura. En el presente trabajo, reportamos una nueva localidad fuera del SHMP y reexaminamos la serie tipo. Internamente, el paratipo macho no posee vestigios masculinos (testículos y conductos seminíferos) por lo que concluimos que hubo un error en el sexado. Además, reportamos una nueva localidad basado en un macho juvenil colectado en el área de Conservación Privada San Luis (ACP San Luis) de la provincia de La Convención. Este nuevo registro incrementa el rango de distribución de la especie en 20.9 km al noreste y su rango altitudinal de 2760 - 2800 a 2760 - 2966 m de altitud.


Proctoporus machupicchu is a semi-fossorial lizard, which was discovered in two locations in the Historic Sanctuary of Machu Picchu (SHMP), Urubamba province, Cusco, Peru. The type series consists of two females and a male, however, the male paratype does not possess femoral pores which is incongruous with the males mentioned in the literature. In this paper, we report a new location outside the SHMP and re-examine the type series. Internally, the male paratype has no male vestiges (testicles and seminiferous ducts), so we conclude that there was an error in sexing. In addition, we report a new locality based on a juvenile male collected in the San Luis Private Conservation Area (ACP San Luis) of La Convención province. This new record increases the range of distribution of the species by 20.9km to the northeast and its altitudinal range from 2760 - 2800 to 2760 - 2966 m of altitude.

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