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1.
BMC Public Health ; 21(1): 1404, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34271884

RESUMO

BACKGROUND: BPaL, a 6 month oral regimen composed of bedaquiline, pretomanid, and linezolid for treating extensively drug-resistant tuberculosis (XDR-TB) is a potential alternative for at least 20 months of individualized treatment regimens (ITR). The ITR has low tolerability, treatment adherence, and success rates, and hence to limit patient burden, loss to follow-up and the emergence of resistance it is essential to implement new DR-TB regimens. The objective of this study was to assess the acceptability, feasibility, and likelihood of implementing BPaL in Indonesia, Kyrgyzstan, and Nigeria. METHODS: We conducted a concurrent mixed-methods study among a cross-section of health care workers, programmatic and laboratory stakeholders between May 2018 and May 2019. We conducted semi-structured interviews and focus group discussions to assess perceptions on acceptability and feasibility of implementing BPaL. We determined the proportions of a recoded 3-point Likert scale (acceptable; neutral; unacceptable), as well as the overall likelihood of implementing BPaL (likely; neutral; unlikely) that participants graded per regimen, pre-defined aspect and country. We analysed the qualitative results using a deductive framework analysis. RESULTS: In total 188 stakeholders participated in this study: 63 from Kyrgyzstan, 51 from Indonesia, and 74 from Nigeria The majority were health care workers (110). Overall, 88% (146/166) of the stakeholders would likely implement BPaL once available. Overall acceptability for BPaL was high, especially patient friendliness was often rated as acceptable (93%, 124/133). In contrast, patient friendliness of the ITR was rated as acceptable by 45%. Stakeholders appreciated that BPaL would reduce workload and financial burden on the health care system. However, several stakeholders expressed concerns regarding BPaL safety (monitoring), long-term efficacy, and national regulatory requirements regarding introduction of the regimen. Stakeholders stressed the importance of addressing current health systems constraints as well, especially in treatment and safety monitoring systems. CONCLUSIONS: Acceptability and feasibility of the BPaL regimen is high among TB stakeholders in Indonesia, Kyrgyzstan, and Nigeria. The majority is willing to start using BPaL as the standard of care for eligible patients despite country-specific health system constraints.


Assuntos
Tuberculose Extensivamente Resistente a Medicamentos , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/uso terapêutico , Estudos de Viabilidade , Humanos , Indonésia , Quirguistão , Nigéria , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
3.
Biochem Biophys Res Commun ; 311(4): 1047-56, 2003 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-14623288

RESUMO

We have recently demonstrated that glucocorticoids protect against serum-deprivation, cAMP-, TNFalpha-, and p53-induced apoptosis in ovarian follicular cells involved in up-regulation of Bcl-2. We demonstrated that dexamethasone, which enhances steroidogenesis by up-regulation of the p450scc enzyme system, stimulates the MAPK cascade by phosphorylation of ERK1, ERK2 as well as by Akt phosphorylation within 1-5min with no effect on p38 MAPK phosphorylation. Moreover, glucocorticoids enhance expression of connexin 43, formation of gap junctions, expression of cadherins, and formation of adherence junctions within 24h of hormone stimulation of ovarian granulosa cells. It is suggested that the protective effects of glucocorticoids against apoptosis are mediated by both genomic and non-genomic mechanisms. Moreover, for the first time we show that protein phosphorylation, cell-cell contact, and intracellular communication are important mediators in glucocorticoid protection against apoptosis in ovarian follicular cells.


Assuntos
Dexametasona/farmacologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/fisiologia , Linhagem Celular , Colforsina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Glucocorticoides/farmacologia , Células da Granulosa/citologia , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Progesterona/biossíntese , Ratos , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia
4.
Biochem Pharmacol ; 66(8): 1355-62, 2003 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-14555209

RESUMO

Ovarian cell death is an essential process for the homeostasis of ovarian function in human and other mammalian species. It ensures the selection of the dominant follicle and the demise of excess follicles. In turn, this process minimizes the possibility of multiple embryo development during pregnancy and assures the development of few, but healthy embryos. Degeneration of the old corpora lutea in each estrus/menstrual cycle by programmed cell death is essential for maintaining the normal cyclicity of ovarian steroidogenesis. Although there are multiple pathways that can determine cell death or survival, crosstalk among endocrine, paracrine and autocrine factors, as well as among protooncogenes, tumor suppressor genes, survival genes and death genes, play an important role in determining the fate of ovarian somatic and germ cells. The establishment of immortalized rat and human steroidogenic granulosa cell lines and the investigation of pure populations of primary granulosa cells allows for systematic studies of the mechanisms that control steroidogenesis and apoptosis of granulosa cells. We have discovered that during initial stages of granulosa cell apoptosis progesterone production does not decrease. In contrast, we found that it is elevated for up to 24hr following the onset of the apoptotic stimuli exerted by starvation, cAMP, p53 or tumor necrosis factor alpha stimulation, before total cell collapse. These observations raise the possibility for an alternative unique apoptotic pathway, one that does not involve mitochondrial cytochrome C release associated with the destruction of mitochondrial structure and steroidogenic function. Using mRNA from apoptotic cells and Affymetrix DNA microarray we discovered that Granzyme B, a protease that normally resides in T cytotoxic lymphocytes and natural killer cells of the immune system is expressed and activated in granulosa cells, thereby allowing the apoptotic signals to bypass mitochondrial signals for apoptosis, which can preserve their steroidogenic activity until complete cell destruction. This unique apoptotic pathway assures the cyclicity of estradiol and progesterone release in the estrus/menstrus cycle even during the initial stage of apoptosis.


Assuntos
Apoptose/fisiologia , Células da Granulosa/fisiologia , Ovário/citologia , Animais , Feminino , Células da Granulosa/citologia , Granzimas , Humanos , Serina Endopeptidases/fisiologia
6.
Biochimie ; 83(8): 783-90, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11530211

RESUMO

The lumen of the endoplasmic reticulum (ER) provides a unique folding environment that is distinct from other organelles supporting protein folding. The relatively oxidizing milieu allows the formation of disulfide bonds. N-linked oligosaccharides that are attached during synthesis play multiple roles in the folding process of glycoproteins. They stabilize folded domains and increase protein solubility, which prevents aggregation of folding intermediates. Glycans mediate the interaction of newly synthesized glycoproteins with some resident ER folding factors, such as calnexin and calreticulin. Here we present an overview of the present knowledge on the folding process of the heavily glycosylated human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein in the ER.


Assuntos
Retículo Endoplasmático/metabolismo , Glicoproteínas/metabolismo , Proteína gp160 do Envelope de HIV/metabolismo , HIV-1/metabolismo , Proteínas de Choque Térmico , Dobramento de Proteína , Sequência de Aminoácidos , Proteínas de Ligação ao Cálcio/metabolismo , Calnexina , Calreticulina , Proteínas de Transporte/metabolismo , Chaperona BiP do Retículo Endoplasmático , Glicosilação , Humanos , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Isomerases de Dissulfetos de Proteínas/metabolismo , Sinais Direcionadores de Proteínas , Ribonucleoproteínas/metabolismo
8.
Virology ; 263(1): 55-69, 1999 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-10544082

RESUMO

HIV-1 LAI is a syncytium-inducing (SI) virus with a broad host cell range. We previously isolated a LAI variant that improved replication in the SupT1 T cell line due to mutations within the C1 and C4 constant regions of the Env protein. We now report that this variant exhibits a severely restricted host cell range, as replication in other T cell lines and primary cells was abolished. Several Env-mediated functions were analyzed to provide a mechanistic explanation for this selective adaptation. The change in host cell tropism was not caused by a switch to a SupT1-specific coreceptor. Biosynthesis of the variant Env glycoprotein was not improved in SupT1 cells, and in fact a small defect in intracellular Env processing was observed. SupT1 infection assays did not reveal an improved Env function either, and a dramatic loss of infectivity was measured with other cell types. The Env-mutated HIV-1 reached an approximately fivefold higher level of virus production in SupT1 cells at the peak of infection. Unlike the LAI virus, the variant did not trigger the formation of syncytia. Our combined results suggest that the HIV-1 variant allows the infected host cell to survive longer, thus producing more viral progeny. The intricate virus-cell interaction results in a balance between optimal virus replication and host cell survival, causing a cytopathic SI isolate to evolve toward a nonsyncytium-inducing (NSI) phenotype in cell culture. These findings may help explain the absence of SI variants in the initial phase of HIV-1 infection, and the results dispute the notion that HIV-1 evolution should always go from the NSI to SI phenotype.


Assuntos
Células Gigantes/fisiologia , HIV-1/fisiologia , Linfócitos T/virologia , Proteínas do Envelope Viral/genética , Replicação Viral , Adaptação Fisiológica , Linhagem Celular , Efeito Citopatogênico Viral , HIV-1/genética , Humanos , Mutação , Proteínas do Envelope Viral/metabolismo , Cultura de Vírus
9.
J Chromatogr A ; 794(1-2): 15-25, 1998 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-9491553

RESUMO

The application of bench-top ion-trap atmospheric pressure ionization mass spectrometry in the characterization of in vitro metabolites of glyburide is discussed. The metabolites formed in vitro by rat, dog, monkey and human liver microsomes were separated by reversed-phase high-performance liquid chromatography (HPLC) and characterized by mass spectrometry (MS)n experiments. The utility of data dependent MS1-MS2-MS3 analyses, where the mass spectrometer makes "real-time" decisions about the experiment to be performed, are described using the characterization of two novel metabolites of glyburide as an example. The metabolite profiles from each species were similar. Six cyclohexyl hydroxylation products were detected, as well as two novel monooxygenation products formed via hydroxylation of the ethyl chain at the benzylic position, and alpha to the amide nitrogen. The ion-trap with electrospray ionization proved to be a sensitive and reliable HPLC detection system that provided important chemical structure information.


Assuntos
Glibureto/farmacocinética , Hipoglicemiantes/farmacocinética , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão , Glibureto/análise , Humanos , Hipoglicemiantes/análise , Técnicas In Vitro , Indicadores e Reagentes , Espectrometria de Massas , Microssomos Hepáticos/metabolismo , Ratos
10.
J Chromatogr A ; 771(1-2): 119-25, 1997 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-9210315

RESUMO

The specificity and selectivity of LC-MS-MS is illustrated to explain why LC-MS-MS has become the method of choice for quantitation within the pharmaceutical industry. Two assays are described that demonstrate the facility with which new ion trap technology can utilize the selectivity and sensitivity of LC-MS-MS to quantitate trace level components within complex matrices, in particular human plasma. One assay undergoes a validation procedure and demonstrates the utility of this new technology for drug quantitation within a regulated environment.


Assuntos
Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocortisona/sangue , Espectrometria de Massas/métodos , Testosterona/sangue , Calibragem , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tiazóis/análise
14.
Eur J Pharmacol ; 70(4): 531-40, 1981 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-6263640

RESUMO

Peptides based in the stabilised tetrapeptide HTyr-D-Ala-Gly-MePheOH have been synthesised and shown to have substantial opioid activity both in vitro and in vivo. The selectivity of these compounds of different receptor populations has been investigated using both isolated tissue assays and binding studies. Results suggest that the compounds are potent agonists at mu-receptors with little or no affinity for the delta-receptor population. One of the compounds, RX783006 (HTyr-D-Ala-Gly-MePhe-NH(CH2)2OH), has been tritiated to high specific radioactivity and may prove to be a useful probe in the elucidation of the function of the heterogenous opiate receptor population.


Assuntos
Fragmentos de Peptídeos/metabolismo , Receptores Opioides/metabolismo , beta-Lipotropina/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Ligação Competitiva , Ala(2)-MePhe(4)-Gly(5)-Encefalina , Encefalinas/farmacologia , Cobaias , Íleo/efeitos dos fármacos , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Naloxona/farmacologia , Dor/fisiopatologia , Ensaio Radioligante , Relação Estrutura-Atividade , Ducto Deferente/efeitos dos fármacos
15.
Buenos Aires; Panamericana; 1981. v.1 p. il.col.. (109439).
Monografia em Espanhol | BINACIS | ID: bin-109439
16.
Acta Ophthalmol (Copenh) ; 55(3): 414-21, 1977 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-577353

RESUMO

A retrospective evaluation of the results obtained with primary implantation of an iris clip lens, performed in four Danish eye departments, is given. Altogether 203 implants were carried out. The mean age of the patients at the time of operation was 77 years. Seventeen patients had bilateral implantation. Besides the cataract, the age of the patients was main indication for implantation. Contributing indications were monolateral cataract, macular degeneration, and general somatic or psychic incapacity. The incidence of more serious complications was (more than one complication in some eyes): corneal dystrophy 13/203, deposits on the clip lens or in the pupil 18/203, secondary glaucoma 2/203, macular oedema 2/203, late recurrent hyphaema 2/203 and dislocation of the clip lens 6/203. Seven clip lenses were removed. A corrected visual acuity of 6/12 or above was found in 56% of the cases postoperatively. In spite of the complications it is considered justifiable to continue with clip lens implantation in elderly patients, to solve the optical problems following aphakia.


Assuntos
Extração de Catarata , Oftalmopatias/reabilitação , Lentes , Próteses e Implantes , Adolescente , Adulto , Fatores Etários , Idoso , Estudos de Avaliação como Assunto , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Acuidade Visual
17.
Acta Ophthalmol (Copenh) ; 53(2): 160-6, 1975 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1173997

RESUMO

A malignant melanoma of the choroid was observed in an 11-month-old fair-skinned Danish boy - one of the youngest cases ever published. There was no evidence of pre-existing melanosis of eyes or skin. The tumour showed histopathologically a typical "adult" pattern and was classified as a mixed tumour. The melanin content was marked. In some earlier reports on uveal tumours within the first year of life, pigmentation was sparse or lacking; a hypothesis has therefore previously been advanced: That melanomas are unable to produce melanin so early in life. The present case renders proof against this hypothesis.


Assuntos
Neoplasias da Coroide/patologia , Melanoma/patologia , Fatores Etários , Corpo Ciliar/patologia , Humanos , Lactente , Masculino , Melaninas , Pigmentos da Retina
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