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1.
J Med Virol ; 92(12): 3403-3411, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32270883

RESUMO

Hepatitis B virus (HBV) infection is estimated to affect 292 million people worldwide, 90% of them are unaware of their HBV status. The Determine HBsAg 2 (Alere Medical Co, Ltd Chiba Japan [Now Abbott]) is a rapid test that meets European Union (EU) regulatory requirements for Hepatitis B surface antigen 2 (HBsAg) analytical sensitivity, detecting the 0.1 IU/mL World Health Organization (WHO) International HBsAg Standard. This prospective, multicentre study was conducted to establish its clinical performance. 351 evaluable subjects were enrolled, 145 HBsAg-positive. The fingerstick whole blood sensitivity and specificity were 97.2% and 98.5% (15' reading, reference assay cut-off 0.05 IU/mL), sensitivity increasing to 97.9% with the prespecified cut-off 0.13 IU/mL (EU regulations). The venous whole blood, serum and plasma sensitivity was 97.2%, 97.9%, and 98.6%, respectively (15' reading); reaching 99%, 99.5% and 100% specificity. A testing algorithm following up an initial positive fingerstick test result with plasma/serum test demonstrates 100% specificity. The Determine HBsAg 2 test gives 15-minute results with high sensitivity and specificity, making it an ideal tool for point-of-care testing, with the potential to enable large-scale population-wide screening to reach the WHO HBV diagnostic targets. The evaluated test improves the existing methods as most of the reviewed rapid tests do not meet the EU regulatory requirements of sensitivity.

3.
Bioorg Med Chem Lett ; 27(16): 3629-3635, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28729055

RESUMO

In 2014, a published report of the high-throughput screen of>42,000 kinase inhibitors from GlaxoSmithKline against T. brucei identified 797 potent and selective hits. From this rich data set, we selected NEU-0001101 (1) for hit-to-lead optimization. Through our preliminary compound synthesis and SAR studies, we have confirmed the previously reported activity of 1 in a T. brucei cell proliferation assay and have identified alternative groups to replace the pyridyl ring in 1. Pyrazole 24 achieves improvements in both potency and lipophilicity relative to 1, while also showing good in vitro metabolic stability. The SAR developed on 24 provides new directions for further optimization of this novel scaffold for anti-trypanosomal drug discovery.


Assuntos
Desenho de Fármacos , Pirazóis/síntese química , Quinazolinonas/química , Tripanossomicidas/síntese química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Quinazolinonas/síntese química , Quinazolinonas/farmacologia , Quinazolinonas/uso terapêutico , Relação Estrutura-Atividade , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma brucei brucei/crescimento & desenvolvimento , Tripanossomíase Africana/tratamento farmacológico
4.
Endocr Pract ; 20(5): 452-60, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24325996

RESUMO

OBJECTIVE: To describe the state of glycemic control in noncritically ill diabetic patients admitted to the Puerto Rico University Hospital and adherence to current standard of care guidelines for the treatment of diabetes. METHODS: This was a retrospective study of patients admitted to a general medicine ward with diabetes mellitus as a secondary diagnosis. Clinical data for the first 5 days and the last 24 hours of hospitalization were analyzed. RESULTS: A total of 147 noncritically ill diabetic patients were evaluated. The rates of hyperglycemia (blood glucose ≥180 mg/dL) and hypoglycemia (blood glucose <70 mg/dL) were 56.7 and 2.8%, respectively. Nearly 60% of patients were hyperglycemic during the first 24 hours of hospitalization (mean random blood glucose, 226.5 mg/dL), and 54.2% were hyperglycemic during the last 24 hours of hospitalization (mean random blood glucose, 196.51 mg/dL). The mean random last glucose value before discharge was 189.6 mg/dL. Most patients were treated with subcutaneous insulin, with basal insulin alone (60%) used as the most common regimen. The proportion of patients classified as uncontrolled receiving basal-bolus therapy increased from 54.3% on day 1 to 60% on day 5, with 40% continuing to receive only basal insulin. Most of the uncontrolled patients had their insulin dose increased (70.1%); however, a substantial proportion had no change (23.7%) or even a decrease (6.2%) in their insulin dose. CONCLUSION: The management of hospitalized diabetic patients is suboptimal, probably due to clinical inertia, manifested by absence of appropriate modification of insulin regimen and intensification of dose in uncontrolled diabetic patients. A comprehensive educational diabetes management program, along with standardized insulin orders, should be implemented to improve the care of these patients.


Assuntos
Diabetes Mellitus/terapia , Idoso , Diabetes Mellitus/sangue , Feminino , Hemoglobinas Glicadas/análise , Hospitais Universitários , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Microbiol Spectr ; 12(1): e0167923, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009959

RESUMO

IMPORTANCE: The COVID-19 pandemic has revealed the lack of effective treatments against betacoronaviruses and the urgent need for new broad-spectrum antivirals. Natural products are a valuable source of bioactive compounds with pharmaceutical potential that may lead to the discovery of new antiviral agents. Specifically, compared to conventional synthetic molecules, microbial natural extracts possess a unique and vast chemical diversity and are amenable to large-scale production. The implementation of a high-throughput screening platform using the betacoronavirus OC43 in a human cell line infection model has provided proof of concept of the approach and has allowed for the rapid and efficient evaluation of 1,280 microbial extracts. The identification of several active compounds validates the potential of the platform for the search for new compounds with antiviral capacity.


Assuntos
Produtos Biológicos , Coronavirus Humano OC43 , Humanos , Produtos Biológicos/farmacologia , Produtos Biológicos/metabolismo , Pandemias , Linhagem Celular , Antivirais/farmacologia
6.
Biochim Biophys Acta ; 1820(12): 2062-71, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23000572

RESUMO

BACKGROUND: Leishmania donovani - the causative agent of visceral leishmaniasis - has several evolutionary characteristics that make the disease difficult to combat. Among these differences, a rare heterodimeric DNA topoisomerase IB has been reported thus opening a new promising field in the therapy of leishmaniasis. Several studies of the human enzyme have pointed to the importance of the linker domain in respect to camptothecin sensitivity. At present, it has been impossible to pinpoint the regions that make up the linker domain in Leishmania. METHODS: Several site-directed mutations as well as internal and linear truncations involving both subunits were assayed on both, relaxation activity and sensitivity to camptothecin. RESULTS: Truncations performed on the trypanosomatids conserved motif (RPPVVRS) of the small subunit of leishmanial DNA topoisomerase IB demonstrated that elimination of pentapeptide RPPVV produced a nonfunctional enzyme. However, the removal of the dipeptide RS led to an enzyme with reduced relaxation activity and less sensitivity to camptothecin. The basic structure, both sensitive to camptothecin and able to fully relax DNA, composed of amino acids 1-592 and 175-262 in the large and small subunits, respectively. CONCLUSION: It has been established that the region between amino acids 175 and 180 (RPPVV) of the small subunit plays a pivotal role in both interaction with the large subunit and sensitivity to camptothecin in Leishmania. GENERAL SIGNIFICANCE: The present report describes a functional analysis of the leishmanial DNA topoisomerase IB regions directly involved both in sensitivity to poisons and in the conformation of the linker domain.


Assuntos
Camptotecina/farmacologia , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/metabolismo , Resistência a Medicamentos , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/enzimologia , Fragmentos de Peptídeos/metabolismo , DNA Topoisomerases Tipo I/genética , DNA de Protozoário/química , DNA de Protozoário/genética , Humanos , Mutagênese Sítio-Dirigida , Mutação/genética , Fragmentos de Peptídeos/genética , Inibidores da Topoisomerase I/farmacologia
7.
Biochem Soc Trans ; 41(4): 934-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23863159

RESUMO

The complex life cycle of Trypanosoma brucei provides an excellent model system to understand signalling pathways that regulate development. We described previously the classical functions of TOR (target of rapamycin) 1 and TOR2 in T. brucei. In a more recent study, we described a novel TOR kinase, named TOR4, which regulates differentiation from the proliferative infective form to the quiescent form. In contrast with TOR1 loss-of-function, down-regulation of TOR4 triggers an irreversible differentiation process through the development of the insect pre-adapted quiescent form. TOR4 governs a signalling pathway distinct from those controlled by the conventional TOR complexes TORC1 and TORC2. Depletion of TOR4 induces all well-known characteristics of the quiescent developmental stage in trypanosomes, including expression of the PAD (proteins associated with differentiation) surface proteins and transcriptional down-regulation of the VSG (variant surface glycoprotein) gene. TOR4 kinase forms a structurally and functionally distinct complex named TORC4. TOR4 associates with LST8 (lethal with sec-13 protein 8) and other factors including an armadillo-domain-containing protein and the major vault protein, which probably serves as a scaffold for this kinase. Research in T. brucei, a protozoan parasite that diverged from the eukaryotic tree early in evolution, may help to uncover new functions of TOR kinases.


Assuntos
Serina-Treonina Quinases TOR/metabolismo , Trypanosoma brucei brucei/enzimologia , Animais , Estágios do Ciclo de Vida , Transdução de Sinais , Trypanosoma brucei brucei/fisiologia
8.
Rev Enferm ; 36(9): 50-5, 2013 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-24245420

RESUMO

OBJECTIVE: To determine if patient safety culture is measurable in healthcare organizations, if it has done, and in this case, how it is measured and which aspects have been taken into account. METHOD: Literature review in the main database with a combination of DeCS and MeSH. LIMITS: 5 years, English and Spanish and this kind of documents: meta-analysis, clinical trials and systematic reviews. Critical reading was performed by CASPe lists. RESULTS: We selected 1 qualitative meta-analysis and 4 revisions. In them a thorough study of measurement tools is made. It is noticeable the great variability in content, size and focus. Although most takes into account the dimensions of leadership communication, procedures, personnel and reporting of incidents. Psychometric analysis is not always adequate and only one has established links with the results with certainty. The most qualified questionnaires are Safety Attitudes Questionnaire (SAQ) and the Hospital Survey on Patient Safety Culture (HSOPSC). Both widely used and with an appropriate psychometric analysis. CONCLUSIONS: Understanding the characteristics that define the patient safety culture is complex. Although the recommended questionnaires are the best at this time, it would be advisable to follow researching in the measuring tools. Patient safety requires an organizational and multidisciplinary approach, however, nursing plays a key role taking into account the rate of preventable adverse events, medication errors, pressure ulcers, lack of information, falls, nosocomial infections, ... are, in largely, within its competence.


Assuntos
Cultura Organizacional , Segurança do Paciente , Humanos
9.
Swiss Med Wkly ; 153: 40085, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37410941

RESUMO

ACKGROUND AND AIMS: The prevalence of chronic hepatitis C in Switzerland is currently estimated at approximately 32,000 affected individuals (0.37% of the permanent resident population). An estimated 40% of affected individuals in Switzerland is undiagnosed. The Swiss Federal Office of Public Health requires laboratories to report all positive hepatitis C virus (HCV) test results. Approximately 900 newly diagnosed cases are reported annually. The number of HCV tests performed, however, is not collected by the Federal Office of Public Health and positive rates are therefore unknown. The aim of this study was to describe the longitudinal course of the numbers of hepatitis C antibody tests and of positive rates in Switzerland for the years 2007 to 2017. METHODS: Twenty laboratories were asked to provide the number of HCV antibody tests performed and the number of positive antibody tests per year. Using data from the Federal Office of Public Health reporting system for the years 2012 to 2017, we calculated a factor to correct our values for multiple tests of the same person. RESULTS: The annual number of HCV antibody tests performed tripled linearly from 2007 to 2017 (from 42,105 to 121,266) while the number of positive HCV antibody test results increased by only 75% over the same period (from 1360 to 2379). The HCV antibody test positive rate steadily decreased from 3.2% in 2007 to 2.0% in 2017. After correction for multiple tests per person, the person-level HCV antibody tested positive rate decreased from 2.2% to 1.7% from 2012 to 2017. CONCLUSION: In the Swiss laboratories considered, more HCV antibody tests were performed each year in the period (2007-2017) before and during the approval of the new hepatitis C drugs. At the same time, the HCV antibody positive rates decreased, both on a per-test as well as a per-person level. This study is the first to describe the evolution of tests performed and of positive rates for HCV antibody in Switzerland at the national level over several years. In order to more accurately guide future measures to achieve the goal of eliminating hepatitis C by 2030, we recommend annual collection and publication of positive rates by health authorities, along with mandatory reporting of numbers of tests and people treated.


Assuntos
Hepatite C , Humanos , Suíça/epidemiologia , Estudos Longitudinais , Estudos Retrospectivos , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepacivirus
10.
Front Microbiol ; 14: 1122489, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37266018

RESUMO

Introduction: Interest for bee microbiota has recently been rising, alleviating the gap in knowledge in regard to drivers of solitary bee gut microbiota. However, no study has addressed the microbial acquisition routes of tropical solitary bees. For both social and solitary bees, the gut microbiota has several essential roles such as food processing and immune responses. While social bees such as honeybees maintain a constant gut microbiota by direct transmission from individuals of the same hive, solitary bees do not have direct contact between generations. They thus acquire their gut microbiota from the environment and/or the provision of their brood cell. To establish the role of life history in structuring the gut microbiota of solitary bees, we characterized the gut microbiota of Centris decolorata from a beach population in Mayagüez, Puerto Rico. Females provide the initial brood cell provision for the larvae, while males patrol the nest without any contact with it. We hypothesized that this behavior influences their gut microbiota, and that the origin of larval microbiota is from brood cell provisions. Methods: We collected samples from adult females and males of C. decolorata (n = 10 each, n = 20), larvae (n = 4), and brood cell provisions (n = 10). For comparison purposes, we also sampled co-occurring female foragers of social Apis mellifera (n = 6). The samples were dissected, their DNA extracted, and gut microbiota sequenced using 16S rRNA genes. Pollen loads of A. mellifera and C. decolorata were analyzed and interactions between bee species and their plant resources were visualized using a pollination network. Results: While we found the gut of A. mellifera contained the same phylotypes previously reported in the literature, we noted that the variability in the gut microbiota of solitary C. decolorata was significantly higher than that of social A. mellifera. Furthermore, the microbiota of adult C. decolorata mostly consisted of acetic acid bacteria whereas that of A. mellifera mostly had lactic acid bacteria. Among C. decolorata, we found significant differences in alpha and beta diversity between adults and their brood cell provisions (Shannon and Chao1 p < 0.05), due to the higher abundance of families such as Rhizobiaceae and Chitinophagaceae in the brood cells, and of Acetobacteraceae in adults. In addition, the pollination network analysis indicated that A. mellifera had a stronger interaction with Byrsonima sp. and a weaker interaction with Combretaceae while interactions between C. decolorata and its plant resources were constant with the null model. Conclusion: Our data are consistent with the hypothesis that behavioral differences in brood provisioning between solitary and social bees is a factor leading to relatively high variation in the microbiota of the solitary bee.

11.
PLoS Negl Trop Dis ; 17(9): e0011592, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37713416

RESUMO

Neglected diseases caused by kinetoplastid parasites are a health burden in tropical and subtropical countries. The need to create safe and effective medicines to improve treatment remains a priority. Microbial natural products are a source of chemical diversity that provides a valuable approach for identifying new drug candidates. We recently reported the discovery and bioassay-guided isolation of a novel family of macrolides with antiplasmodial activity. The novel family of four potent antimalarial macrolides, strasseriolides A-D, was isolated from cultures of Strasseria geniculata CF-247251, a fungal strain obtained from plant tissues. In the present study, we analyze these strasseriolides for activity against kinetoplastid protozoan parasites, namely, Trypanosoma brucei brucei, Leishmania donovani and Trypanosoma cruzi. Compounds exhibited mostly low activities against T. b. brucei, yet notable growth inhibition and selectivity were observed for strasseriolides C and D in the clinically relevant intracellular T. cruzi and L. donovani amastigotes with EC50 values in the low micromolar range. Compound C is fast-acting and active against both intracellular and trypomastigote forms of T. cruzi. While cell cycle defects were not identified, prominent morphological changes were visualized by differential interference contrast microscopy and smaller and rounded parasites were visualized upon exposure to strasseriolide C. Moreover, compound C lowers parasitaemia in vivo in acute models of infection of Chagas disease. Hence, strasseriolide C is a novel natural product active against different forms of T. cruzi in vitro and in vivo. The study provides an avenue for blocking infection of new cells, a strategy that could additionally contribute to avoid treatment failure.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma brucei brucei , Trypanosoma cruzi , Animais , Doença de Chagas/tratamento farmacológico , Macrolídeos/farmacologia
12.
Front Microbiol ; 14: 1149145, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234530

RESUMO

Acanthamoeba species, Naegleria fowleri, and Balamuthia mandrillaris are opportunistic pathogens that cause a range of brain, skin, eye, and disseminated diseases in humans and animals. These pathogenic free-living amoebae (pFLA) are commonly misdiagnosed and have sub-optimal treatment regimens which contribute to the extremely high mortality rates (>90%) when they infect the central nervous system. To address the unmet medical need for effective therapeutics, we screened kinase inhibitor chemotypes against three pFLA using phenotypic drug assays involving CellTiter-Glo 2.0. Herein, we report the activity of the compounds against the trophozoite stage of each of the three amoebae, ranging from nanomolar to low micromolar potency. The most potent compounds that were identified from this screening effort were: 2d (A. castellanii EC50: 0.92 ± 0.3 µM; and N. fowleri EC50: 0.43 ± 0.13 µM), 1c and 2b (N. fowleri EC50s: <0.63 µM, and 0.3 ± 0.21 µM), and 4b and 7b (B. mandrillaris EC50s: 1.0 ± 0.12 µM, and 1.4 ± 0.17 µM, respectively). With several of these pharmacophores already possessing blood-brain barrier (BBB) permeability properties, or are predicted to penetrate the BBB, these hits present novel starting points for optimization as future treatments for pFLA-caused diseases.

14.
Bioorg Med Chem Lett ; 22(1): 440-3, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22119463

RESUMO

Twenty compounds selected as representative members of three series of long-chain 1,2-diamines, 2-amino-1-alkanols and 1-amino-2-alkanols structurally related to dihydrosphingosin, were synthesized and tested in vitro for their ability to inhibit the sleeping sickness parasites Trypanosoma bruceirhodesiense and Trypanosoma brucei gambiense. Eight compounds showed EC(50) values in the submicromolar range, with selectivity indexes up to 39 related to the respective cytotoxicity values for Vero cells. The parasite phenotype detected after treatment with the most potent compounds showed irreversible cell morphology alterations of the flagellar pocket that lead to inhibition of cell growth and parasite death.


Assuntos
Álcoois/química , Química Farmacêutica/métodos , Diaminas/química , Trypanosoma brucei brucei/metabolismo , Animais , Morte Celular , Chlorocebus aethiops , Desenho de Fármacos , Humanos , Modelos Químicos , Fenótipo , Fatores de Tempo , Tripanossomicidas/farmacologia , Tripanossomíase Africana/parasitologia , Células Vero
15.
STAR Protoc ; 3(2): 101250, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35313711

RESUMO

Oxygen in vertebrates is generally provided through respiratory organs and blood vessels. This protocol describes transcardial injection, vascular distribution, and accumulation of phototrophic microalgae in the brain of Xenopus laevis tadpoles. Following tissue isolation, oxygen dynamics and neuronal activity are recorded in semi-intact whole-head preparations. Illumination of such microalgae-filled preparations triggers the photosynthetic production of oxygen in the brain that, under hypoxic conditions, rescues neuronal activity. This technology is potentially able to ameliorate consequences of hypoxia under pathological conditions. For complete details on the use and execution of this protocol, please refer to Özugur et al. (2021).


Assuntos
Microalgas , Animais , Encéfalo , Neurônios , Oxigênio , Xenopus laevis
16.
Int J Pharm ; 613: 121417, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34965466

RESUMO

This study reports the use of Raman and Near-infrared (NIR) spectroscopy to simultaneously monitor the drug concentration in flowing powder blends within a three-chamber feed frame. The Raman probe was located at the top of the dosing chamber, while the NIR probe was located at the top of the filling chamber. The Raman and NIR spectra were continuously acquired while the powder blends flowed through the feed frame. Calibration models were developed with spectra from a total of five calibration blends ranging in caffeine concentration among 3.50 and 6.50% w/w. These models were optimized to predict three test set blends of 4.00, 5.00, and 6.00% w/w caffeine. The results showed a high predictive ability of the models based on root mean square error of predictions of 0.174 and 0.235% w/w for NIR and Raman spectroscopic models, respectively. Concentration profiles with higher variability were observed for the Raman spectroscopy predictions. An estimate of the mass analyzed by each spectrum showed that a NIR spectrum analyzes approximately 4.5 times the mass analyzed by a Raman spectrum; despite these differences in the mass analyzed, blend uniformity results are equivalent between techniques. Variographic analysis demonstrated that both techniques have significantly low sampling errors for the real-time monitoring process of drug concentration within the feed frame.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , Composição de Medicamentos , Pós , Comprimidos
17.
Cells ; 11(3)2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35159329

RESUMO

The oligodendrocyte progenitors (OPCs) are at the front of the glial reaction to the traumatic brain injury. However, regulatory pathways steering the OPC reaction as well as the role of reactive OPCs remain largely unknown. Here, we compared a long-lasting, exacerbated reaction of OPCs to the adult zebrafish brain injury with a timely restricted OPC activation to identify the specific molecular mechanisms regulating OPC reactivity and their contribution to regeneration. We demonstrated that the influx of the cerebrospinal fluid into the brain parenchyma after injury simultaneously activates the toll-like receptor 2 (Tlr2) and the chemokine receptor 3 (Cxcr3) innate immunity pathways, leading to increased OPC proliferation and thereby exacerbated glial reactivity. These pathways were critical for long-lasting OPC accumulation even after the ablation of microglia and infiltrating monocytes. Importantly, interference with the Tlr1/2 and Cxcr3 pathways after injury alleviated reactive gliosis, increased new neuron recruitment, and improved tissue restoration.


Assuntos
Células Precursoras de Oligodendrócitos , Animais , Encéfalo , Gliose/metabolismo , Imunidade Inata , Células Precursoras de Oligodendrócitos/metabolismo , Peixe-Zebra
18.
iScience ; 24(10): 103158, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34755084

RESUMO

Neuronal activity in the brain depends on mostly aerobic generation of energy equivalents and thus on a constant O2 supply. Oxygenation of the vertebrate brain has been optimized during evolution by species-specific uptake and transport of O2 that originally derives from the phototrophic activity of prokaryotic and eukaryotic organisms in the environment. Here, we employed a concept that exploits transcardial injection and vascular distribution of unicellular green algae or cyanobacteria in the brain of Xenopus laevis tadpoles. Using oxygen measurements in the brain ventricle, we found that these microorganisms robustly produce sizable amounts of O2 upon illumination. In a severe hypoxic environment, when neuronal activity has completely ceased, the photosynthetic O2 reliably provoked a restart and rescue of neuronal activity. In the future, phototrophic microorganisms might provide a novel means to directly increase oxygen levels in the brain in a controlled manner under particular eco-physiological conditions or following pathological impairments.

19.
J Med Chem ; 64(13): 9404-9430, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34156862

RESUMO

Neglected tropical diseases such as human African trypanosomiasis (HAT) are prevalent primarily in tropical climates and among populations living in poverty. Historically, the lack of economic incentive to develop new treatments for these diseases has meant that existing therapeutics have serious shortcomings in terms of safety, efficacy, and administration, and better therapeutics are needed. We now report a series of 3,5-disubstituted-7-azaindoles identified as growth inhibitors of Trypanosoma brucei, the parasite that causes HAT, through a high-throughput screen. We describe the hit-to-lead optimization of this series and the development and preclinical investigation of 29d, a potent antitrypanosomal compound with promising pharmacokinetic (PK) parameters. This compound was ultimately not progressed beyond in vivo PK studies due to its inability to penetrate the blood-brain barrier (BBB), critical for stage 2 HAT treatments.


Assuntos
Indóis/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase Africana/tratamento farmacológico , Relação Dose-Resposta a Droga , Humanos , Indóis/síntese química , Indóis/química , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química
20.
Gastroenterology ; 136(5): 1651-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19208350

RESUMO

BACKGROUND & AIMS: Simvastatin improves liver generation of nitric oxide and hepatic endothelial dysfunction in patients with cirrhosis, so it could be an effective therapy for portal hypertension. This randomized controlled trial evaluated the effects of continuous simvastatin administration on the hepatic venous pressure gradient (HVPG) and its safety in patients with cirrhosis and portal hypertension. METHODS: Fifty-nine patients with cirrhosis and portal hypertension (HVPG > or =12 mm Hg) were randomized to groups that were given simvastatin 20 mg/day for 1 month (increased to 40 mg/day at day 15) or placebo in a double-blind clinical trial. Randomization was stratified according to whether the patient was being treated with beta-adrenergic blockers. We studied splanchnic and systemic hemodynamics and variables of liver function and safety before and after 1 month of treatment. RESULTS: Simvastatin significantly decreased HVPG (-8.3%) without deleterious effects in systemic hemodynamics. HVPG decreases were observed in patients who were receiving beta-adrenergic blockers (-11.0%; P = .033) and in those who were not (-5.9%; P = .013). Simvastatin improved hepatic, fractional, and intrinsic clearance of indocyanine green, showing an improvement in effective liver perfusion and function. No significant changes in HVPG and liver function were observed in patients receiving placebo. The number of patients with adverse events did not differ significantly between groups. No patient was withdrawn from the study based on adverse events. CONCLUSIONS: Simvastatin decreased HVPG and improved liver perfusion in patients with cirrhosis. These effects were additive with those of beta-adrenergic blockers. The beneficial effects of simvastatin should be confirmed in long-term clinical trials for portal hypertension.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipertensão Portal/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Pressão na Veia Porta/efeitos dos fármacos , Sinvastatina/uso terapêutico , Antagonistas Adrenérgicos beta/uso terapêutico , Método Duplo-Cego , Feminino , Hemodinâmica , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Hipolipemiantes/efeitos adversos , Circulação Hepática/efeitos dos fármacos , Cirrose Hepática/complicações , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Sinvastatina/efeitos adversos
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