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1.
J Family Med Prim Care ; 11(6): 2557-2564, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36119165

RESUMO

Context: Climate change is the biggest global health threat and also the greatest health opportunity of the 21st century. Five warmest years among the last 140 years occurred between 2015 and 2019. Limited information is available regarding the knowledge and practices of medical students towards climate change, especially in India. Settings and Design: A cross-sectional survey was conducted in two medical colleges of Karimnagar city from January 2021 to July 2021 involving MBBS and Post-graduate students as study participants. Methods and Material: 903 undergraduate and post-graduate medical students who consented for the study were included. A pre-structured questionnaire was used. Statistical Analysis Used: Data is presented in frequencies and proportions with 95% confidence interval and Chi-square test is used as test of significance. Results: Poor knowledge regarding Sustainable Developmental Goal for climate action, Organisations dealing climate change and Government actions towards climate change were observed among study participants. Cardiovascular and respiratory diseases (84%) were answered as the major health impacts of climate change. Majority (97.4%) of the participants agreed that 'human actions are also the cause for global warming'. Environment-friendly practices were observed significantly high among participants with adequate knowledge. Major (72%) source of learning about climate change was via internet. Conclusions: Our study found that major proportion of participants doesn't have environment-friendly practices. However, the participants with adequate knowledge about climate change were observed to have more eco-friendly practices compared to participants with inadequate knowledge.

2.
Malays Orthop J ; 16(1): 58-69, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35519524

RESUMO

Introduction: Lateral epicondylitis is a painful condition of the elbow, characterised by pain and tenderness with resisted wrist extension. This study was carried out to evaluate the comparative efficacy of the local infiltration of L-PRP, methylprednisolone and normal saline in patients with lateral epicondylitis. Materials and methods: Sixty adult patients, between the ages 30 to 50 years, diagnosed with lateral epicondylitis of more than 12 weeks, were enrolled in the prospective randomised study. Their medical history and previous conservative treatment were recorded; the clinical evaluation of the tendinitis was made with the visual analogue scale (VAS), the disabilities of the arm, shoulder, and hand (DASH) outcome scores, the modified elbow performance index (MEPS), the functional assessment by patient-rated tennis elbow evaluation (PRTEE), together with the laboratory investigations. The patients were randomised using the computer-generated alphabets into three groups of 20: group A received saline, group B received PRP, and group C received corticosteroids. Results: Patients were seen at 4, 8 and 12 weeks to evaluate the post-injection status. VAS, DASH, and PRTEE scores were significantly reduced, and MEPS was significantly improved in group B compared to group A and group C. Moreover, the reductions in VAS and PRTEE were significantly different in group C compared to group A. Conclusion: PRP leads to superior healing with long-term therapeutic advantages compared to corticosteroids though it takes a little longer to have its effect.

3.
J Laryngol Otol ; 135(10): 892-896, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34372962

RESUMO

OBJECTIVE: Behavioural modification through increasing nutritional awareness, along with customised dietary changes and education about physical inactivity, for obese snorers and mildly sleep apnoeic patients would help improve their quality of life. METHODS: A one-year prospective interventional study enrolled snorers and/or mild obstructive sleep apnoea sufferers, with 36 patients each in the test group and control group. Nutritional information and tailor-made diet charts were given to the 36 test subjects. The severity of snoring and daytime sleepiness after 6 and 12 months was compared using the Epworth Sleepiness Scale and Thornton Snoring Scale as measures of quality of life. RESULTS: Subjective scores on both scales showed highly significant improvement (p ≤ 0.001) in the test group. No significant improvement was seen in the control group. CONCLUSION: Awareness of basic nutrition and customised diet plans help to achieve behavioural modification in the long term, resulting in a better quality of life.


Assuntos
Dieta Redutora/psicologia , Síndromes da Apneia do Sono/psicologia , Apneia Obstrutiva do Sono/psicologia , Ronco/psicologia , Adulto , Idoso , Conscientização , Índice de Massa Corporal , Estudos de Casos e Controles , Ingestão de Alimentos , Exercício Físico/fisiologia , Comportamento Alimentar/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional/fisiologia , Polissonografia/métodos , Estudos Prospectivos , Qualidade de Vida , Comportamento de Redução do Risco , Índice de Gravidade de Doença , Síndromes da Apneia do Sono/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Ronco/fisiopatologia
4.
Mymensingh Med J ; 27(2): 424-428, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29769514

RESUMO

Cleidocranial dysplasia is a developmental anomaly of the skeleton and the teeth. This condition may be inherited and be transmitted as dominant characteristics in either gender, or may appear spontaneously. It presents with skeletal defects of several bones, such as partial or complete absence of clavicles, late closure of the fontanels, presence of open skull sutures and multiple wormian bones. The dental manifestations are mainly delayed exfoliation of primary teeth and delayed eruption of permanent teeth with multiple impacted supernumerary teeth. This case of a 20 year old girl is noteworthy to the dentist as it deals with clinical and radiological features (a high number of impacted and supernumerary teeth as well as brachycephaly, frontal bossing and hypermobility of shoulders) which may come handy in clinical practice.


Assuntos
Displasia Cleidocraniana , Dente Impactado , Dente Supranumerário , Displasia Cleidocraniana/complicações , Displasia Cleidocraniana/diagnóstico por imagem , Craniossinostoses , Feminino , Humanos , Radiografia , Erupção Dentária , Adulto Jovem
5.
Ann Med Health Sci Res ; 6(5): 261-266, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28503341

RESUMO

BACKGROUND: Hypothyroidism, one of the most common endocrine disorders, may induce neurological abnormalities at an early stage of the disease. AIM: The study was designed to assess the electrophysiological alterations of some selected variables of nerve conduction, brainstem auditory evoked potentials (BAEPs), and visual evoked potentials (VEPs) in hypothyroid patients. SUBJECTS AND METHODS: Sixty patients of newly diagnosed hypothyroidism and an equal number of age-matched controls were selected for the study. Nerve conduction studies that included parameters as latencies, conduction velocities, and amplitude of motor nerves, i.e., median, ulnar, common peroneal, tibial nerve, and sensory nerves, i.e., median and sural nerves was performed in both hypothyroid patients and controls. Further, BAEPs and VEPs of all the patients were done. The data were compiled and statistically analyzed using Student's unpaired t-test to observe any electrophysiological alterations in hypothyroid patients as compared to healthy controls. RESULTS: On comparative evaluation, statistically significant increase in latency of median, ulnar, tibial, and sural nerves; decrease in conduction velocities of all the tested nerves and decrease in amplitude of median, tibial, and sural nerves was observed in hypothyroid patients. Statistically significant increase in latencies, interpeak latencies, and decrease in amplitudes of BAEP waves and statistically significant increase in P100 latency of VEP was seen in hypothyroid patients. CONCLUSION: The results of our study suggest that peripheral and central neuropathy develops in patients of hypothyroidism at an early stage of disease and the electrophysiological investigations of such patients can help in timely detection and treatment of neurological disorders that occur due to thyroid hormone deficiency.

6.
J Perinatol ; 36(1): 67-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26583940

RESUMO

OBJECTIVE: The objective of this study was to evaluate and compare the efficacy of combined sucrose and non-nutritive sucking (NNS) for analgesia in newborn infants undergoing heel-stick procedures. STUDY DESIGN: This randomized control trial was conducted in the neonatal intensive care unit of a tertiary care hospital over a period of 1 year. One hundred and eighty full-term neonates with birth weight >2200 g and age >24 h were randomized to one of four interventions administered 2 min before the procedure: 2 ml of 30% sucrose (group I, n=45) or NNS (group II, n=45) or both (group III, n=45) or none (group IV, n=45). Primary outcome was composite score based on Premature Infant Pain Profile (PIPP) score. RESULT: Baseline variables were comparable among the groups. Median (interquartile range) PIPP score was 3 (2 to 4) in group III as compared with 7 (6.5 to 8) in group I, 9 (7 to 11) in group II and 13 (10.5 to 15) in group IV. Group III had significant decrease in the median PIPP score compared with other groups (P=0.000). Median PIPP score also decreased significantly with any intervention as compared with no intervention (P=0.000). CONCLUSION: Sucrose and/or NNS are effective in providing analgesia in full-term neonates undergoing heel-stick procedures, with the combined intervention being more effective compared with any single intervention.


Assuntos
Analgesia/métodos , Coleta de Amostras Sanguíneas , Adoçantes não Calóricos/administração & dosagem , Manejo da Dor/métodos , Dor/prevenção & controle , Sacarose/administração & dosagem , Feminino , Humanos , Índia , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Medição da Dor , Comportamento de Sucção , Nascimento a Termo , Centros de Atenção Terciária
7.
Genom Data ; 5: 36-37, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26090325

RESUMO

TCF21 is a basic helix-loop-helix transcription factor that has recently been implicated as contributing to susceptibility to coronary heart disease based on genome wide association studies. In order to identify transcriptionally regulated target genes in a major disease relevant cell type, we performed siRNA knockdown of TCF21 in in vitro cultured human coronary artery smooth muscle cells and compared the transcriptome of siTCF21 versus siCONTROL treated cells. The raw (FASTQ) as well as processed (BED) data from 3 technical replicates per treatment has been deposited with Gene Expression Omnibus (GSE44461).

8.
Plant Cell Rep ; 34(1): 63-70, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25261161

RESUMO

KEY MESSAGE: This is a novel report in which chromosomal position of the rice blast resistance gene Pi54 was not found to affect significantly the resistance phenotype or morphological traits. Blast disease caused by Magnaporthe oryzae is a serious constraint in rice production at global level. Pi54 gene imparts resistance against M. oryzae. Three different transgenic lines containing Pi54 and its orthologue Pi54rh were shown to be resistant to different races of M. oryzae. To determine the chromosomal location of Pi54 gene in transgenic lines, inverse PCR was performed. Our analysis showed that in two transgenic lines, Pi54 gene was integrated on chromosomes 6 and 10 at 12.94 and 22.30 Mb, respectively. Similarly, Pi54rh allele was integrated on chromosome 1 at 16.25 Mb. The Pi54 gene present on chromosome 6 was located in a non-coding region whereas in the other TP-Pi54 line, the gene was introgressed on chromosome 10 in between the coding region of SAP domain gene. The Pi54rh was also located in the non coding region flanked by the retrotransposon genes. These rice lines were evaluated for eight different traits related to seed and plant morphology and agronomic features for two consecutive years. The transgenic lines containing Pi54 gene have higher tiller number, grain weight, epicotyl length, and yield compared to the non-transgenic control. Multivariate correlation analysis shows that blast resistance was positively correlated with the number of tillers; thousand grain weight and epicotyl length. These results will facilitate precise utilization of Pi54 gene and its orthologue in breeding programs for the development of rice cultivars with broad spectrum and durable resistance to M. oryzae.


Assuntos
Cromossomos de Plantas/genética , Resistência à Doença/genética , Genes de Plantas/genética , Doenças das Plantas/genética , Mapeamento Cromossômico , Interações Hospedeiro-Patógeno , Hipocótilo/genética , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/microbiologia , Magnaporthe/fisiologia , Análise Multivariada , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Fenótipo , Doenças das Plantas/microbiologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas
9.
Cell Mol Biol (Noisy-le-grand) ; 60(5): 73-81, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25535716

RESUMO

Stress tolerating strain of Pseudomonas aeruginosa PF07 possessing plant growth promoting activity was screened for the production of exopolysaccharides (EPS). EPS production was monitored in the cell free culture supernatant (CFCS) and extracted EPS was further purified by thin layer chromatography. EPS producing cells were taken to design talc based formulation and its efficacy was checked on oilseed crop sunflower (Hellianthus annuus), under in vivo saline conditions (soil irrigated with 125 mM of saline water). Application of bioformulation significantly enhanced the yield and growth attributes of the plant in comparison to control (untreated seeds) under stress and non—stress conditions. Germination rate, plant length, dry weight and seed weight increased remarkably. The above findings suggest the application and benefits of utilizing EPS formulation in boosting early seedling emergence, enhancing plant growth parameters, increasing seed weight and mitigating stress in saline affected regions. Such bioformulation may enhance RAS/RT (Root Adhering Soil to Root Tissue ratio), texture of the soil, increase porosity, improve uptake of nutrients, and hence may be considered as commercially important formulation for renovation of stressed sites and enhancing plant growth.


Assuntos
Helianthus/crescimento & desenvolvimento , Polissacarídeos Bacterianos/metabolismo , Pseudomonas aeruginosa/metabolismo , Talco/metabolismo , Salinidade
11.
Dev Biol ; 342(2): 121-33, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20346940

RESUMO

Activins are members of the TGF-ss superfamily of secreted growth factors that control a diverse array of processes in vertebrates including endocrine function, cell proliferation, differentiation, immune response and wound repair. In Drosophila, the Activin ligand Dawdle (Daw) has been shown to regulate several aspects of neuronal development such as embryonic axonal pathfinding, neuroblast proliferation in the larval brain and growth cone motility in the visual system. Here we identify a novel role for Activin signaling in regulating synaptic growth at the larval neuromuscular junction (NMJ). Mutants for Daw, the Activin type I receptor Baboon (Babo), and the signal transducer dSmad2, display reduced NMJ size suggesting that Daw utilizes a canonical Activin signal-transduction pathway in this context. Additionally, loss of Daw/Babo activity affects microtubule stability, axonal transport and distribution of Futsch, the Drosophila microtubule associated protein 1B (MAP1B) homolog. We find that Babo signaling is required postsynaptically in the muscle, in contrast to the well-characterized retrograde BMP/Gbb signal that is required for synaptic growth and function in presynaptic cells. Finally, we show that the Daw/Babo pathway acts upstream of gbb, and is involved in maintenance of muscle gbb expression, suggesting that Activins regulate NMJ growth by modulating BMP activity through transcriptional regulation of ligand expression.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Receptores de Ativinas/metabolismo , Ativinas/metabolismo , Animais , Proteínas de Transporte/metabolismo , Junção Neuromuscular/metabolismo
12.
Natl Med J India ; 22(4): 181-2, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20120991

RESUMO

Anorexia nervosa is a condition thought to be associated with the western culture. However, the recent publication of a case series from Asia suggests that it is a syndrome related to a changing culture. We present a detailed clinical form of this syndrome based on descriptive analysis of 2 cases of anorexia nervosa. Both these patients were adolescent, school-going girls from middle socioeconomic class of urban background. They were pre-morbidly non-obese and did not have any pressures to pursue slimness for beauty. However, there was an identifiable psychosocial stressor as a precipitant in both of them. Both the patients had symptoms of refusal to eat followed by weight loss. We could not identify any risk factor in our patients for anorexia nervosa. Our report illustrates the differences in developmental and psychodynamic issues related to the development of anorexia nervosa, though the clinical symptoms may be similar.


Assuntos
Anorexia Nervosa/psicologia , Adolescente , Cultura , Feminino , Humanos , Índia , Fatores Socioeconômicos
14.
Prog Mol Subcell Biol ; 34: 73-101, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14979665

RESUMO

Cytokines of the TGF-beta superfamily act through an evolutionarily conserved signaling pathway to elicit a diverse range of biological responses in vertebrates as well as invertebrates. Drosophila has proved to be a powerful system to unravel the profound complexities underlying the regulation of this superficially simple signaling system for two reasons--the availability of sophisticated genetic tools and the restricted number of core signaling components compared to vertebrates. A BMP signaling pathway in Drosophila that regulates growth, differentiation and morphogenesis of the embryo and the larva has been extensively characterized. This work has provided major insights into how gradients of secreted proteins can be established and maintained in vivo, allowing a single ligand to induce multiple cell fates rather than function as an on-off switch. More recently, an activin signaling pathway has also been delineated that is required for growth and neuronal function during development. This review provides an overview of TGF-beta signaling in Drosophila with emphasis on the extensive modulation of signaling activity both within and outside the cell, that enables ligands to trigger specific and context-dependent effects.


Assuntos
Ativinas/fisiologia , Proteínas Morfogenéticas Ósseas/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila/fisiologia , Animais , Drosophila/crescimento & desenvolvimento , Drosophila/imunologia , Ligantes , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
15.
Bioorg Med Chem ; 11(8): 1789-800, 2003 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-12659765

RESUMO

A series of N(1),N(n)-xylofuranosylated diaminoalkanes (3-9 and 11-18) has been synthesized either by reductive amination of deoxy xylouloses (2a, 2b) with amines followed by one pot reduction with NaBH(4) or NaCNBH(3); or by 1,4-conjugate addition of amines to glycosyl olefinic esters (10a, 10b). The compounds were screened for their interference with filarial worms' glutathione metabolism, a potential target for chemotherapeutic attack. Interestingly, these compounds affected intracellular glutathione, gamma-glutamyl cysteine synthetase, glutathione reductase and glutathione-S-transferase(s) of bovine filarial worms to varying degrees. Some of the compounds though effected the motility and MTT reduction potential of filarial worms Brugia malayi, however, little microfilaricidal and macrofilaricidal were noted with compounds at 50mg/kg oral dose. Compounds 6, 16 and 17 were evaluated also for in vivo activity.


Assuntos
Alcanos/síntese química , Alcanos/farmacologia , Antiparasitários/síntese química , Antiparasitários/farmacologia , Diaminas/química , Diaminas/farmacologia , Filarioidea/efeitos dos fármacos , Xilose/análogos & derivados , Alcanos/química , Animais , Antiparasitários/química , Brugia Malayi/efeitos dos fármacos , Butionina Sulfoximina/farmacologia , Carmustina/farmacologia , Bovinos , Inibidores Enzimáticos/farmacologia , Feminino , Filarioidea/enzimologia , Glutamato-Cisteína Ligase/efeitos dos fármacos , Glutamato-Cisteína Ligase/metabolismo , Glutationa/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/efeitos dos fármacos , Glutationa Redutase/metabolismo , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/metabolismo , Masculino , Microfilárias/efeitos dos fármacos , Microfilárias/metabolismo , Roedores/parasitologia , Vitamina K 3/farmacologia
16.
Indian J Psychiatry ; 45(1): 58-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21206818

RESUMO

Anorexia nervosa is regarded a s a typical culture bound syndrome, and its existence is negligible in nonwestern countries due to protective biological and socio-cultural factors. Most of the cases reported from nonwestern countries are atypical in presentation with lack of body image disturbances. Recent studies showed that anorexia nervosa is no more culture bound, in fact it is a "culture change syndrome" due to westernization and no differences are seen in the phenomenology of anorexia nervosa between the two cultures. We report a typical case of anorexia nervosa of binge eating and purging type associated with body dysmorphophobia in an adolescent girl.

17.
Dev Cell ; 1(4): 441-2, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11703932

RESUMO

TGF-beta signaling is modulated by Smurfs, E3-ubiquitin ligases that selectively target the receptors and Smad proteins for degradation. New evidence from Drosophila suggests that Smurfs regulate the amplitude and the duration of the cellular response to signaling in vivo.


Assuntos
Proteínas de Drosophila , Drosophila/metabolismo , Ligases/metabolismo , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases , Animais
18.
Prep Biochem Biotechnol ; 31(2): 185-200, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11426705

RESUMO

Phage display has emerged as a powerful technique for mapping epitopes recognised by monoclonal and polyclonal antibodies. We have recently developed a simple gene-fragment phage display system and have shown its utility in mapping epitope recognised by a monoclonal antibody. In the present study, we have employed this system in mapping epitopes recognised by polyclonal antibodies raised against HIV-1 capsid protein, p24 which is derived from proteolytic cleavage of Gag polyprotein. HIV-1 gag DNA was fragmented by DNase I and the fragments (50-250 bp) were cloned into gene-fragment phage display vector to construct a library of phages displaying peptides. This phage library was used for affinity selection of phages displaying epitopes recognised by rabbit anti-p24 polyclonal antibodies. Selected phages contained sequences from two discrete regions of p24, demonstrating the presence of two antigenic regions. The DNA sequences encoding these regions were also cloned and expressed as GST fusion proteins. The immunoreactivity of these epitopes as GST fusion proteins, or as phage-displayed peptides, was comparable in ELISA system using same anti-p24 polyclonal antibodies. The results indicate that the gene-fragment based phage display system can be used efficiently to identify epitopes recognised by polyclonal antibodies, and phage displayed epitopes can be directly employed in ELISA to detect antibodies.


Assuntos
Mapeamento de Epitopos/métodos , Proteína do Núcleo p24 do HIV/imunologia , Epitopos Imunodominantes/análise , Animais , Primers do DNA/química , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Biblioteca Gênica , Proteína do Núcleo p24 do HIV/genética , HIV-1/genética , Humanos , Biblioteca de Peptídeos , Reação em Cadeia da Polimerase , Coelhos , Proteínas Recombinantes de Fusão/isolamento & purificação
19.
Protein Expr Purif ; 21(3): 378-85, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11281711

RESUMO

A simple and efficient method for expression in Escherichia coli and purification of matrix protein, p17, of human immunodeficiency virus type 1 (HIV-1) of both B- and C-subtypes is described. DNA sequences encoding p17 of B- and C-subtype were cloned from respective gag sequences. The gag sequences were obtained by PCR amplification using DNA extracted from peripheral blood lymphocytes of an HIV-1 infected patient from India. A T7-promoter-based expression system was optimized for expression of p17 in soluble form. p17 (B- and C-subtype) was purified to near homogeneity using conventional chromatographic techniques. Purification of p17 (C-subtype) is described for the first time with yield of 7.7 mg from a 1-liter culture. The yield of p17 (B-subtype) is 14.7 mg from a 1-liter culture, which is severalfold better than that reported earlier. N-terminal sequencing and CD spectra of the purified proteins, p17B and p17C, show that the proteins are properly processed and well-folded. The immunoreactivity of both types of p17 to sera from HIV-infected individuals is comparable.


Assuntos
Produtos do Gene gag/genética , Produtos do Gene gag/isolamento & purificação , Antígenos HIV/genética , Antígenos HIV/isolamento & purificação , Infecções por HIV/virologia , HIV-1/classificação , HIV-1/genética , Proteínas Virais , Sequência de Aminoácidos , Dicroísmo Circular , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Produtos do Gene gag/química , Produtos do Gene gag/imunologia , Vetores Genéticos , Antígenos HIV/química , Antígenos HIV/imunologia , Infecções por HIV/imunologia , HIV-1/química , HIV-1/imunologia , Humanos , Soros Imunes/imunologia , Índia , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Produtos do Gene gag do Vírus da Imunodeficiência Humana
20.
Development ; 128(9): 1657-70, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11290303

RESUMO

Decapentaplegic (Dpp), a homolog of vertebrate bone morphogenic protein 2/4, is crucial for embryonic patterning and cell fate specification in Drosophila. Dpp signaling triggers nuclear accumulation of the Smads Mad and Medea, which affect gene expression through two distinct mechanisms: direct activation of target genes and relief of repression by the nuclear protein Brinker (Brk). The zinc-finger transcription factor Schnurri (Shn) has been implicated as a co-factor for Mad, based on its DNA-binding ability and evidence of signaling dependent interactions between the two proteins. A key question is whether Shn contributes to both repression of brk as well as to activation of target genes. We find that during embryogenesis, brk expression is derepressed in shn mutants. However, while Mad is essential for Dpp-mediated repression of brk, the requirement for shn is stage specific. Analysis of brk; shn double mutants reveals that upregulation of brk does not account for all aspects of the shn mutant phenotype. Several Dpp target genes are expressed at intermediate levels in double mutant embryos, demonstrating that shn also provides a brk-independent positive input to gene activation. We find that Shn-mediated relief of brk repression establishes broad domains of gene activation, while the brk-independent input from Shn is crucial for defining the precise limits and levels of Dpp target gene expression in the embryo.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila , Drosophila/embriologia , Proteínas de Insetos/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Animais , Padronização Corporal , Regulação da Expressão Gênica no Desenvolvimento , Mesoderma , Modelos Genéticos , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail , Transcrição Gênica , Ativação Transcricional , Vísceras/embriologia
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