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1.
Indian Pediatr ; 61(1): 10-23, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38183246

RESUMO

JUSTIFICATION: Neurodevelopmental disorders, as per DSM-V, are described as a group of conditions with onset in the development period of childhood. There is a need to distinguish the process of habilitation and rehabilitation, especially in a developing country like India, and define the roles of all stakeholders to reduce the burden of neurodevelopmental disorders. PROCESS: Subject experts and members of Indian Academy of Pediatrics (IAP) Chapter of Neurodevelopmental Pediatrics, who reviewed the literature on the topic, developed key questions and prepared the first draft on guidelines. The guidelines were then discussed by the whole group through online meetings, and the contentious issues were discussed until a general consensus was arrived at. Following this, the final guidelines were drafted by the writing group and approved by all contributors. OBJECTIVES: These guidelines aim to provide practical clinical guidelines for pediatricians on the prevention, early diagnosis and management of neurodevelopmental disorders (NDDs) in the Indian settings. It also defines the roles of developmental pediatricians and development nurse counselor. STATEMENT: There is a need for nationwide studies with representative sampling on epidemiology of babies with early NDD in the first 1000 days in India. Specific learning disability (SLD) has been documented as the most common NDD after 6 years in India, and special efforts should be made to establish the epidemiology of infants and toddlers at risk for SLD, where ever measures are available. Preconception counseling as part of focusing on first 1000 days; Promoting efforts to organize systematic training programs in Newborn Resuscitation Program (NRP); Lactation management; Developmental follow-up and Early stimulation for SNCU/ NICU graduates; Risk stratification of NICU graduates, Newborn Screening; Counseling parents; Screening for developmental delay by trained professionals using simple validated Indian screening tools at 4, 8, 12, 18 and 24 months; Holistic assessment of 10 NDDs at child developmental clinics (CDCs) / district early intervention centre (DEICs) by multidisciplinary team members; Confirmation of diagnosis by developmental pediatrician/developmental neurologist/child psychiatrist using clinical/diagnostic tools; Providing parent guided low intensity multimodal therapies before 3 years age as a center-based or home-based or community-based rehabilitation; Developmental pediatrician to seek guidance of pediatric neurologist, geneticist, child psychiatrist, physiatrist, and other specialists, when necessary; and Need to promote ongoing academic programs in clinical child development for capacity building of community based therapies, are the chief recommendations.


Assuntos
Transtornos do Neurodesenvolvimento , Criança , Humanos , Lactente , Recém-Nascido , Academias e Institutos , Diagnóstico Precoce , Índia , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/epidemiologia , Transtornos do Neurodesenvolvimento/prevenção & controle
2.
Malays J Pathol ; 45(2): 149-155, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37658525

RESUMO

Prostate cancer is the second-most frequently diagnosed cancer in men worldwide. Serum prostatespecific antigen is currently used for the early detection of prostate cancer. However, new biomarkers are needed to decrease over diagnosis and over treatment of prostate cancer due to limitations of prostate-specific antigen. Recently, molecular biomarkers have shown promising results for diagnosis and prognosis of prostate cancer. Molecular biomarkers have improved the sensitivity and specificity of prostate-specific antigen and studies are ongoing to identify molecular biomarkers as a replacement for prostate-specific antigen. This review aims to give an overview of emerging molecular biomarkers for diagnosis and prognosis of prostate cancer.


Assuntos
Segunda Neoplasia Primária , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico , Prognóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Mutação
3.
BMC Complement Altern Med ; 17(1): 104, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28187719

RESUMO

BACKGROUND: Liver cancer is a high incidence and fatal disease, the fifth most frequent cancer worldwide that is usually diagnosed at an advanced stage. The number of deaths from liver cancer has not declined even following various therapies. Plant secondary metabolites and their semi-synthetic derivatives play a principal role in anti-cancer drug therapy, since they are effective in the treatment of specific characteristics while also reducing side effects. Allium atroviolaceum, a plant of the genus Allium has been used in folk medicine to protect against several diseases. However, cytotoxicity and the anti-proliferative effect of Allium atroviolaceum remain unclear. This work aims to investigate the anticancer properties of Allium atroviolaceum and the mechanism of action. METHODS: To evaluate the in vitro cytotoxicity of flower of Allium atroviolaceum, methanol extract at a dose range from 100 to 3.12 µg/ml was assessed against the HepG2 hepatocarcinoma cell line, and also on normal 3T3 cells, by monitoring proliferation using the MTT assay method. A microscopy study was undertaken to observe morphological changes of HepG2 cells after treatment and cell cycle arrest and apoptosis were studied using flow cytometry. The apoptosis mechanism of action was assessed by the level of caspase-3 activity and expression of apoptosis related genes, Bcl-2, Cdk1 and p53. The combination effect of the methanolic extract with doxorubicin was also investigated by determination of a combination index. RESULTS: The results demonstrated growth inhibition of cells in both dose- and time-dependent manners, while no cytotoxic effect on normal cell 3T3 was found. The results revealed the occurrence of apoptosis, illustrated by sub-G0 cell cycle arrest, the change in morphological feature and annexin-V and propidium iodide staining, which is correlated with Bcl-2 downregulation and caspase-3 activity, but p53-independent. In addition, a combination of Allium atroviolaceum and doxorubicin led to a significant synergistic effect. CONCLUSION: These findings suggest that Allium atroviolaceum flower extract has potential as a potent cytotoxic agent against HepG2 cell lines, as it has commendable anti-proliferative activities against human hepatocarcinoma and it can be considered as an effective adjuvant therapeutic agent after the clinical trials.


Assuntos
Allium/química , Apoptose/efeitos dos fármacos , Flores/química , Extratos Vegetais/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Humanos
4.
Nat Prod Commun ; 12(3): 439-440, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30549905

RESUMO

The chemical constituents and anti-inflammatory activity of the essential oil from the leaf of Jatropha curcas L (Euphorbiaceae) collected from Nigeria are reported. The analysis of the chemical constituents of the essential oil was achieved by using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). All constituents of the essential oil, namely neophytadiene (35.8%), phytol (23.1%), trans-pinane (12.7%), 6,10,14-trimethyl-2- pentadecanone (12:3%) and citronellyl propanoate (11.2%), were present in significant amounts. The anti-inflammatory activity of the leaf oil was determined on Wistar rats using egg-albumin as phlogistic agent; significant inhibition (P< 0.05) was shown at a dose of 2%, v/v. Percentage inhibition of the anti- inflammation increased steadily to 76.6% in the 4th hour.


Assuntos
Anti-Inflamatórios/farmacologia , Jatropha/química , Óleos Voláteis/química , Folhas de Planta/química , Óleos de Plantas/química , Animais , Anti-Inflamatórios/química , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Masculino , Extratos Vegetais/química , Ratos
5.
Genet Mol Res ; 15(2)2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27323204

RESUMO

The aim of this study was to determine whether C34T, a common polymorphism of the adenosine monophosphate deaminase 1 gene (AMPD1), is associated with essential hypertension (EH). We hypothesize that C34T is associated with the development of EH. A case-control design was used for this study. The DNA was extracted using a commercial kit from the whole blood of 200 patients with hypertension and 200 subjects without hypertension from selected Malaysian ethnicities (Malays, Chinese, and Indians). Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and agarose gel electrophoresis were used for genotyping. The C34T gene polymorphism of AMPD1 was significantly associated with EH in the Malaysian subjects (P < 0.0001). The genotype frequencies of CC, CT, and TT were 6%, 79%, and 15%, respectively, among hypertensive subjects, while no TT genotypes were observed in the normotensive subjects. Further, the frequency of hypertension was higher among T allele carriers than C carriers (OD = 9.94; 95%CI = 6.851-14.434). There were significant differences in the systolic blood pressure, diastolic blood pressure, and pulse pressure (P ˂ 0.05) between the normotensive and hypertensive Malaysian subjects; we believe those difference were caused by the C34T polymorphism. For the first time in Malaysia, the current study provides evidence that a common polymorphism of the AMPD1 gene (C34T) is strongly associated with EH.


Assuntos
AMP Desaminase/genética , Hipertensão/genética , Polimorfismo de Nucleotídeo Único , Idoso , Estudos de Casos e Controles , Feminino , Heterozigoto , Humanos , Malásia , Masculino , Pessoa de Meia-Idade
6.
Cell Mol Biol (Noisy-le-grand) ; 62(6): 44-9, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27262801

RESUMO

Acute myeloid leukemia (AML) is one of the most frequent types of leukemia which mostly affects adult people. Resistance to therapeutic drugs is considered as a major clinical concern resulting in a weaker response to chemotherapy, disease relapse and decreased survival rate. Survivin, a member of Inhibitor of Apoptosis Proteins (IAPs), is associated with drug resistance and inhibition of apoptotic mechanisms in numerous hematological malignancies. In the present study, we examined the combined effect of etoposide and siRNA-mediated silencing of survivin on U-937 acute myeloid leukemia cells. The AML cells were transfected with survivin specific siRNA and gene knockdown was confirmed by quantitative real time PCR and western blotting. Subsequently, U-937 cells were assessed for response to etoposide treatment and apoptosis rate was measured with flowcytometery. The cytotoxic effects in siRNA-etoposide group were measured and compared to etoposide single therapy group. Survivin siRNA effectively knocked down the mRNA and protein levels of survivin, which led to lower cell proliferation and enhanced apoptosis. Furthermore, combined treatment of etoposide and survivin siRNA synergistically increased the cell toxic effects of etoposide and its ability to induce apoptosis.


Assuntos
Antineoplásicos/uso terapêutico , Etoposídeo/uso terapêutico , Proteínas Inibidoras de Apoptose/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , RNA Interferente Pequeno/metabolismo , Anexina A5/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Interações Medicamentosas , Etoposídeo/farmacologia , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Concentração Inibidora 50 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Survivina , Transfecção , Células U937
7.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173202

RESUMO

Type 2 diabetes mellitus (T2DM) is believed to be associated with excessive production of reactive oxygen species. Glutathione S-transferase (GST) polymorphisms result in decreased or absent enzyme activity and altered oxidative stress, and have been associated with cardiovascular disease (CVD). The present study assessed the effect of GST polymorphisms on the risk of developing T2DM in individuals of Malaysian Malay ethnicity. A total of 287 subjects, consisting of 87 T2DM and 64 CVD/T2DM patients, as well as 136 healthy gender- and age-matched controls were genotyped for selected polymorphisms to evaluate associations with T2DM susceptibility. Genomic DNA was extracted using commercially available kits, and GSTM1, GSTT1, and α-globin sequences were amplified by multiplex polymerase chain reaction. Biochemical parameters were measured with a Hitachi autoanalyzer. The Fisher exact test, the chi-square statistic, and means ± standard deviations were calculated using the SPSS software. Overall, we observed no significant differences regarding genotype and allele frequencies between each group (P = 0.224 and 0.199, respectively). However, in the combined analysis of genotypes and blood measurements, fasting plasma glucose, HbA1c, and triglyceride levels, followed by age, body mass index, waist-hip ratio, systolic blood pressure, and history of T2DM significantly differed according to GST polymorphism (P ˂ 0.05). Genetically induced absence of the GSTT1 enzyme is an independent and powerful predictor of premature vascular morbidity and death in individuals with T2DM, and might be triggered by cigarette smoking's oxidative effects. These polymorphisms could be screened in other ethnicities within Malaysia to determine further possible risk factors.


Assuntos
Doenças Cardiovasculares/genética , Diabetes Mellitus Tipo 2/genética , Glutationa Transferase/genética , Polimorfismo de Nucleotídeo Único , Alelos , Doenças Cardiovasculares/complicações , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Feminino , Genótipo , Humanos , Malásia , Masculino , alfa-Globinas/genética
8.
Genet Mol Res ; 15(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27173219

RESUMO

Hemoglobin (Hb) Adana [HBA2: c179G>A (or HBA1); p.Gly60Asp] is a non-deletional α-thalassemia variant found in Malaysia. An improvement in the molecular techniques in recent years has made identification of Hb Adana much easier. For this study, a total of 26 Hb Adana α-thalassemia intermedia and 10 Hb Adana trait blood samples were collected from patients. Common deletional and non-deletional α-thalassemia genotypes were determined using multiplex gap polymerase chain reaction (PCR) and multiplex ARMS PCR techniques. Identification of the Hb Adana location on the α-globin gene was carried out using genomic sequencing and the location of the mutation was confirmed via restriction fragment length polymorphism-PCR. Among the 36 samples, 24 (66.7%) had the -α(3.7)/α(Cd59)α mutation, while the -α(3.7)/α(Cd59)α mutation accounted for 2 samples (5.6%) and the remaining 10 (27.8%) samples were α/α(Cd59)α. All 36 samples were found to have the Hb Adana mutation on the α2-globin gene. The position of the α-globin gene mutation found in our cases was similar to that reported in Indonesia (16%) but not to that in Turkey (0.6%). Our results showed that the Hb Adana mutation was preferentially present in the α2-globin genes in Malays compared to the other ethnicities in Malaysia. Thus, the Malays might have similar ancestry based on the similarities in the Hb Adana position.


Assuntos
Hemoglobina A/genética , Hemoglobinas Anormais/genética , Talassemia alfa/genética , Humanos , Malásia , Mutação Puntual , Polimorfismo de Fragmento de Restrição , Talassemia alfa/etnologia
9.
J Biol Regul Homeost Agents ; 29(2): 395-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26122228

RESUMO

Tumor protein p53 encoded by the TP53 gene in humans is known as a cancer biomarker in patients diagnosed with cancer, and it plays an essential role in apoptosis, genomic stability, and inhibition of angiogenesis. Cancer therapies with common chemotherapy methods are effective, as known, but have some side effects. Berberis vulgaris is traditionally administrated as a cancer drug. The current research aims to evaluate p53 as a biomarker in WEHI-3 cell line and to demonstrate the Berberis vulgaris fruit crude extract (BVFCE) as a new anticancer drug. For this purpose, we evaluated the effect of BVFCE in different concentrations against WEHI-3cell line in vitro and determined the quantitative level of p53 gene in the treated WEHI-3 cells. The results demonstrated that even at only 1 mg/ml concentration of Berberis vulgaris crude extract, there was a low level of p53 biomarker expression on WEHI-3 cells in comparison with doxorubicin. Therefore, the current study suggests BVFCE as a reliable anti-leukaemic drug and candidate for anticancer therapy. However, further investigation need be carried out to confirm its efficiency in vivo.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Berberis/química , Frutas/química , Leucemia Experimental/patologia , Leucemia Mielomonocítica Aguda/patologia , Fitoterapia , Extratos Vegetais/farmacologia , Células 3T3 , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Genes p53 , Concentração Inibidora 50 , Camundongos , Proteína Supressora de Tumor p53/análise
10.
Genet Mol Res ; 14(4): 18974-9, 2015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-26782547

RESUMO

This study aims to investigate the effects of tumor necrosis factor alpha (TNF-α) G308A gene polymorphism on essential hypertension (EHT) with or without type 2 diabetes mellitus (T2DM). The project was conducted on buccal epithelial and blood cells for case and control patients, respectively. Epithelial cells were obtained from the inner part of the cheeks. Techniques including DNA extraction, polymerase chain reaction (PCR), and restriction fragment length polymorphism (RFLP) were utilized to assess biomarkers of DNA damage. Our results demonstrated significant differences between wild and mutated genotypes among EHT patients without T2DM. We also found a significant association between wild and mutated allele frequencies in EHT patients (P < 0.05). Clinical characteristics between the groups (EHT with or without T2DM and controls) showed statistically significant association (P < 0.05). Overall, we show that G308A polymorphism of the TNF-αgene may be a significant genetic risk factor for EHT without T2DM patients in Malaysia.


Assuntos
Hipertensão/genética , Fator de Necrose Tumoral alfa/genética , Idoso , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/genética , Hipertensão Essencial , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
11.
Genet Mol Res ; 13(2): 2939-48, 2014 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-24782128

RESUMO

The sympathetic nervous system plays a major role in blood pressure regulation. Beta 2 (ß2) adrenoceptor gene polymorphisms have been associated with hypertension in different populations with conflicting results. We examined the association of three common polymorphisms, Arg16Gly, Gln27Glu, and Thr164Ile, of the ß2 adrenoceptor gene in Malaysian hypertensive subjects. A total of 160 hypertensive and control subjects were recruited. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and anthropometric measurements were obtained from each subject. Biochemical analyses of lipid profiles were conducted with an autoanalyzer. DNA samples were extracted from blood and buccal cells. Genotyping was accomplished with polymerase chain reaction-restriction fragment length polymorphism. SBP, DBP, body mass index, and biochemical factors all differed significantly between case and control subjects (P < 0.05). The genotype frequencies of Arg16Arg, Arg16Gly, and Gly16Gly were 22.5, 70, and 7.5% among cases and 33.1, 63.1, and 3.8% among controls, respectively. The genotype frequencies of Gln27Gln, Gln27Glu, and Glu27Glu among cases were 41.1, 50, and 1.9% compared to 77.5, 20.6, and 1.9% among controls, respectively. In this study, the Gln27Glu polymorphism was significantly associated with Malaysian hypertensive subjects (P < 0.05). Therefore, the Gln27Glu polymorphism of the ß2 adrenoceptor could be a risk factor associated with hypertension among Malaysians.


Assuntos
Pressão Sanguínea/genética , Estudos de Associação Genética , Hipertensão/genética , Receptores Adrenérgicos beta 2/genética , Adulto , Povo Asiático , Feminino , Genótipo , Humanos , Hipertensão/patologia , Malásia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco
12.
Balkan J Med Genet ; 17(1): 37-40, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25741213

RESUMO

The aim of this study was to determine the association of the c.894G>T; p.Glu298Asp polymorphism and the variable number tandem repeat (VNTR) polymorphism of the endothelial nitric oxide synthase (eNOS) gene and c.181C>T polymorphism of the bradykinin type 2 receptor gene (B2R) in Malaysian end-stage renal disease (ESRD) subjects. A total of 150 ESRD patients were recruited from the National Kidney Foundation's (NKF)dialysis centers in Malaysia and compared with 150 normal healthy individuals. Genomic DNA was extracted from buccal cells of all the subjects. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was carried out to amplify the products and the restricted fragments were separated by agarose gel electrophoresis. Statistical analyses were carried out using software where a level of p <0.05 was considered to be statistically significant. The genotypic and allelic frequencies of the B2R gene (c.181C>T, 4b/a) and eNOS gene (c.894G>T) polymorphisms were not statistically significant (p >0.05) when compared to the control subjects. The B2R and eNOS gene polymorphisms may not be considered as genetic susceptibility markers for Malaysian ESRD subjects.

13.
Balkan J Med Genet ; 16(2): 45-52, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24778563

RESUMO

The ageing process is influenced by many internal and external factors. The toxic substances in the environment can cause genomic damages to cells, which increase the risk of early ageing. Furthermore, the cytochrome P450 1A2 (CYP1A2) gene polymorphism is a susceptibility factor and may enhance the risk of DNA damage in cells. The current study was carried out to show whether occupational exposure could cause genotoxicity in cells carrying the CYP1A2 gene polymorphism, thus enhancing the likelihood of early ageing. This study was conducted on mechanical workshop workers and a control group by collecting buccal cells from their mouths. Restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) was used to identify the CYP1A2 gene polymorphism in the cells. In addition, three extra methods including micronuclei (MN) test, comet assay and real-time PCR (RT-PCR) were applied to determine the effects of gene polymorphisms on DNA damage and ageing from occupational exposure. The results showed that DNA damage in the cells carrying the mutated genotype was higher than the wild genotype. In addition, the difference in MN frequency (p = 0.001) and relative telomere length (p = 0.002) between workers and controls was significant (p <0.05) in the mutated genotype. The findings indicated a possible protective effect of gene polymorphism against early ageing, which was characterized by lack of a significant influence of CYP1A2 gene polymorphism on genetic material in the subjects (p >0.05). It was concluded that the CYP1A2 gene could be a contributing factor to prevent early ageing from occupational exposure.

14.
Genet Mol Res ; 11(2): 1486-96, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22653598

RESUMO

We evaluated the possible influence of glutathione S-transferase mu (GSTM1) and glutathione S-transferase theta (GSTT1) genes on genetic damage due to occupational exposure, which contributes to accelerate ageing. This study was conducted on 120 car auto repair workshop workers exposed to occupational hazards and 120 controls without this kind of exposure. The null and non-null genotypes of GSTM1 and GSTT1 genes were determined by multiplex PCR. Micronucleus frequency, Comet tail length and relative telomere length differences between the null and non-null genotypes of the GSTM1 gene were significantly greater in the exposed group. Lack of GSTT1 did not affect the damage biomarkers significantly (P > 0.05), while lack of GSTM1 was associated with greater susceptibility to genomic damage due to occupational exposure. It was concluded that early ageing is under the influence of these genes and the environmental and socio-demographic factors. Duration of working time was significantly associated with micronucleus frequency, Comet tail length and relative telomere length.


Assuntos
Envelhecimento/fisiologia , Glutationa Transferase/genética , Exposição Ocupacional/efeitos adversos , Envelhecimento/genética , Ensaio Cometa , Dano ao DNA/genética , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase Multiplex
15.
J Endocrinol ; 180(2): 287-95, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14765981

RESUMO

Progesterone, via its nuclear receptor, is mandatory not only for the induction and specification of mammary gland ductal side-branching and lobuloalveologenesis but also for carcinogen-induced mammary tumorigenesis. Notwithstanding these recent advances, a more comprehensive molecular explanation of progesterone-induced mammary morphogenesis is contingent upon the identification and characterization of mammary molecular targets that are responsive to the progesterone signal. Toward this goal, we report that calcitonin, a 32 amino acid peptide hormone involved in calcium homeostasis, is exclusively expressed in, and secreted from, luminal epithelial cells within the mammary gland of the pregnant mouse, and, importantly, its expression is progesterone-dependent. Conversely, the calcitonin receptor is present during all stages of post-natal mammary development examined, is localized to the myoepithelial cell lineage, and is not regulated by progesterone. Because calcitonin induction spatiotemporally correlates with increases in progesterone-induced mammary gland proliferation and structural remodeling, we posit that calcitonin - through its receptor - may be involved in one or both of these progesterone-dependent processes.


Assuntos
Calcitonina/metabolismo , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo , Prenhez/metabolismo , Progesterona/metabolismo , Animais , Calcitonina/análise , Calcitonina/genética , Divisão Celular , Estrogênios/farmacologia , Feminino , Imuno-Histoquímica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Knockout , Gravidez , Progesterona/genética , Progesterona/farmacologia , RNA/análise , Receptores da Calcitonina/análise , Receptores da Calcitonina/metabolismo
16.
Oncogene ; 18(40): 5582-91, 1999 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-10523835

RESUMO

USF is a family of transcription factors that are structurally related to the Myc oncoproteins and also share with Myc a common DNA-binding specificity. USF overexpression can prevent c-Myc-dependent cellular transformation and also inhibit the proliferation of certain transformed cells. These antiproliferative activities suggest that USF inactivation could be implicated in carcinogenesis. To explore this possibility, we compared the activities of the ubiquitous USF1 and USF2 proteins in several cell lines derived from either normal breast epithelium or breast tumors. The DNA-binding activities of USF1 and USF2 were present at similar levels in all cell lines. In the non-tumorigenic MCF-10A cells, USF in general, and USF2 in particular, exhibited strong transcriptional activities. In contrast, USF1 and USF2 were completely inactive in three out of six transformed breast cell lines investigated, while the other three transformed cell lines exhibited loss of USF2 activity. Analyses in cells cultured from healthy tissue confirmed the transcriptional activity of USF in normal human mammary epithelial cells. These results demonstrate that a partial or complete loss of USF function is a common event in breast cancer cell lines, perhaps because, like Myc overexpression, it favors rapid proliferation.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Proteínas de Ligação a DNA , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/deficiência , Fatores de Transcrição/deficiência , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Mama/citologia , Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/metabolismo , Células Cultivadas , DNA/metabolismo , Células Epiteliais/metabolismo , Feminino , Genes Reporter , Genes myc , Humanos , Metástase Neoplásica , Proteínas de Neoplasias/genética , Fenótipo , Proteínas Recombinantes de Fusão/biossíntese , Fatores de Transcrição/genética , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Fatores Estimuladores Upstream
17.
Mol Cell Biol ; 19(2): 1508-17, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9891084

RESUMO

USF1 and USF2 are basic helix-loop-helix transcription factors implicated in the control of cellular proliferation. In HeLa cells, the USF proteins are transcriptionally active and their overexpression causes marked growth inhibition. In contrast, USF overexpression had essentially no effect on the proliferation of the Saos-2 osteosarcoma cell line. USF1 and USF2 also lacked transcriptional activity in Saos-2 cells when assayed by transient cotransfection with USF-dependent reporter genes. Yet, there was no difference in the expression, subcellular localization, or DNA-binding activity of the USF proteins in HeLa and Saos-2 cells. Furthermore, Gal4-USF1 and Gal4-USF2 fusion proteins activated transcription similarly in both cell lines. Mutational analysis and domain swapping experiments revealed that the small, highly conserved USF-specific region (USR) was responsible for the inactivity of USF in Saos-2 cells. In HeLa, the USR serves a dual function. It acts as an autonomous transcriptional activation domain at promoters containing an initiator element and also induces a conformational change that is required for USF activity at promoters lacking an initiator. Taken together, these results suggest a model in which the transcriptional activity of the USF proteins, and consequently their antiproliferative activity, is tightly controlled by interaction with a specialized coactivator that recognizes the conserved USR domain and, in contrast to USF, is not ubiquitous. The activity of USF is therefore context dependent, and evidence for USF DNA-binding activity in particular cells is insufficient to indicate USF function in transcriptional activation and growth control.


Assuntos
Divisão Celular/fisiologia , Proteínas de Ligação a DNA , Fatores de Transcrição/metabolismo , Ativação Transcricional , Sequência de Aminoácidos , Linhagem Celular , DNA/genética , DNA/metabolismo , Expressão Gênica , Genes Reporter , Células HeLa , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Modelos Biológicos , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Frações Subcelulares/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Transfecção , Fatores Estimuladores Upstream , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo
18.
Integration ; (60): 25, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-12322184

RESUMO

PIP: While Malaysia already had policies for a balanced, equitable, and sustainable development before the 1994 International Conference on Population and Development (ICPD), the conference gave Malaysia the chance to pursue specific and more complex issues. Reproductive health services including family planning have been integrated and are available, accessible, and affordable within the existing health care system, both public and private. Since Malaysia's government needs help implementing Cairo's goals, regular consultations are held with advocacy groups, the private sector, and community groups on program design and implementation. Annual grants to nongovernmental organizations are made to ensure that programs and services ultimately reach the various target groups. While Malaysia has made progress implementing the ICPD program of action, it has more to accomplish. Economic conditions leading to a 20% across-the-board budget cut in July 1998 have not adversely affected the country's population and reproductive health programs.^ieng


Assuntos
Administração Financeira , Acessibilidade aos Serviços de Saúde , Necessidades e Demandas de Serviços de Saúde , Cooperação Internacional , Organização e Administração , População , Medicina Reprodutiva , Mudança Social , Ásia , Sudeste Asiático , Anticoncepção , Países Desenvolvidos , Países em Desenvolvimento , Economia , Europa (Continente) , Serviços de Planejamento Familiar , Saúde , Agências Internacionais , Malásia , Países Baixos , Organizações , Nações Unidas
19.
Oncogene ; 16(18): 2321-31, 1998 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-9620549

RESUMO

The v-fps oncogene encodes an activated tyrosine kinase which is capable of transforming fibroblasts. In this report, we provide evidence that within a few minutes of activation of the tyrosine kinase activity of v-Fps, tyrosine phosphorylation of the platelet derived growth factor (PDGF) beta receptor is observed. Further, sustained expression of activated v-Fps results in a down-regulation of the PDGF receptor both at the level of the mRNA (approximately 4-8-fold), but even more markedly at the level of the receptor protein (> 100-fold). The kinase activity of the v-Fps oncoprotein was found to be required for both the induction of PDGF receptor tyrosine phosphorylation and ultimately the reduced receptor protein levels. Tyrosine phosphorylation of a kinase inactive PDGF receptor was also demonstrated in cells which also express v-fps, but this was not sufficient to induce transformation. Only cells expressing both v-fps and a wild type PDGF receptor were able to form colonies in soft agar. These findings suggest that wild type v-fps may use tyrosine phosphorylation of the PDGFbeta receptor to constitutively activate the kinase activity of the receptor, resulting in a sustained proliferative signal and fibroblast transformation.


Assuntos
Transformação Celular Neoplásica , Proteínas de Fusão gag-onc/metabolismo , Proteínas Tirosina Quinases/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Comunicação Celular , Linhagem Celular , Dados de Sequência Molecular , Fosforilação , RNA Mensageiro/análise , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Receptores do Fator de Crescimento Derivado de Plaquetas/genética , Homologia de Sequência de Aminoácidos , Tirosina
20.
Gen Comp Endocrinol ; 98(1): 87-93, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7540160

RESUMO

Juvenile hormone (JH) regulation of the synthesis of LHPI, the major secretory protein of the long hyaline tubule in the male accessory reproductive gland (MARG) of Melanoplus sanguinipes, was examined by in vitro radiolabeling and immunoprecipitation. In MARG taken from normal insects JH III immediately stimulates production of immunospecific LHPI. In contrast, JH III does not initially promote synthesis of LHPI in MARG of allatectomized insects. Only after prior exposure to the hormone [for 24 hr when applied in vivo (topically) or 16 hr under in vitro conditions] is LHPI synthesis enhanced by JH III in the MARG of allatectomized insects. These results suggest that in the prolonged absence of JH III the MARG are "switched off," that is, lose their sensitivity to the hormone. Sensitivity is regained during the 24- or 16-hr "lag phase." Use of the translational inhibitor cycloheximide confirmed the existence of the lag phase in JH III-mediated LHPI synthesis. JH III stimulates RNA synthesis in a dose-dependent manner in the long hyaline tubule at concentrations < 64 nM. Above this level, RNA synthesis was depressed. Actinomycin D given simultaneously with JH III inhibited RNA synthesis, but not the synthesis of LHPI in the long hyaline tubule. It is suggested that understanding the nature of the lag phase will facilitate clarification of the mechanism of action of JH in the MARG.


Assuntos
Glicoproteínas/biossíntese , Gafanhotos/metabolismo , RNA/biossíntese , Sesquiterpenos/farmacologia , Animais , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Masculino , Metionina/metabolismo
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