RESUMO
Begomoviruses have increased pathogenicity because of their adaptation to a wide host range; consequently, these viruses cause a major loss to agroeconomic crops worldwide. In this study, we designed a gene construct representing an antisense coat protein gene. We also analyzed the efficacy of the induced resistance against Croton yellow vein mosaic virus (CrYVMV) affecting papaya in Nicotiana tabacum plants. Positive control plants developed typical leaf curl symptoms, whereas transgenic plants were symptomless. Moreover, the key component (i.e., short interfering RNA) of the antisense pathway was upregulated in transgenic plants. This finding demonstrates the activation of the gene silencing mechanism in transgenic plants. Thus, these results confirm that our construct is functional and effectively induces transient resistance against CrYVMV infections.
Assuntos
Begomovirus/genética , Croton/virologia , Vírus do Mosaico/genética , Nicotiana/virologia , Doenças das Plantas/virologia , Carica/virologia , Inativação Gênica/fisiologia , Especificidade de Hospedeiro/genética , Folhas de Planta/virologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/virologia , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genéticaRESUMO
The global regulatory veA gene governs development and secondary metabolism in numerous fungal species, including Aspergillus flavus. This is especially relevant since A. flavus infects crops of agricultural importance worldwide, contaminating them with potent mycotoxins. The most well-known are aflatoxins, which are cytotoxic and carcinogenic polyketide compounds. The production of aflatoxins and the expression of genes implicated in the production of these mycotoxins are veA dependent. The genes responsible for the synthesis of aflatoxins are clustered, a signature common for genes involved in fungal secondary metabolism. Studies of the A. flavus genome revealed many gene clusters possibly connected to the synthesis of secondary metabolites. Many of these metabolites are still unknown, or the association between a known metabolite and a particular gene cluster has not yet been established. In the present transcriptome study, we show that veA is necessary for the expression of a large number of genes. Twenty-eight out of the predicted 56 secondary metabolite gene clusters include at least one gene that is differentially expressed depending on presence or absence of veA. One of the clusters under the influence of veA is cluster 39. The absence of veA results in a downregulation of the five genes found within this cluster. Interestingly, our results indicate that the cluster is expressed mainly in sclerotia. Chemical analysis of sclerotial extracts revealed that cluster 39 is responsible for the production of aflavarin.
Assuntos
Aflatoxinas/genética , Aspergillus flavus/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Genes Reguladores/genética , Família Multigênica/genética , Metabolismo Secundário/genética , Fatores de Transcrição/genética , Aflatoxinas/biossíntese , Aspergillus flavus/patogenicidade , Perfilação da Expressão Gênica , Transcriptoma/genéticaRESUMO
Leaves of sunn hemp (Crotalaria juncea) showing geminiviral symptoms were collected from Lucknow, India during rainy season in 2008. DNA template isolated from the symptomatic leaf tissues were subjected to polymerase chain reaction (PCR) using specific primers to amplify coat protein (CP) gene of DNA-A as well as betasatellite DNA associated with the leaf curl disease. CP gene showed 97% sequence identity with that of Cotton leaf curl Burewala virus (CLCuBwV). Further, the betasatellite DNA molecule revealed sequence similarity with previously characterized betasatellite DNA of begomoviruses affecting malvaceous crops from different regions of India and Pakistan. Maximum similarity (>90%) of betasatellite DNA under study was observed with Cotton leaf curl Multan betasatellite (CLCuMB-[Pak: Mul17:08) and other betasatellite DNA from Pakistan thus confirming possible infection of C. juncea with begomovirus. A complementary sense open reading frame (ORF) ßC1 is present at nucleotide position 194-550. Sequence comparison of this ORF with other members of begomoviruses further confirmed association of a begomovirus with C. juncea. The betasatellite DNA when expressed under the control of CaMV35S promoter Nicotiana tabacum, showed leaf deformities. Our results demonstrated that a malvaceous betasatellite is adapted by a nonmalvaceous host and causes similar disease symptoms.
Assuntos
Begomovirus/genética , Cannabis/virologia , DNA Satélite , Doenças das Plantas/virologia , Begomovirus/classificação , Begomovirus/isolamento & purificação , Begomovirus/fisiologia , DNA Viral/genética , Índia , Dados de Sequência Molecular , Filogenia , Nicotiana/virologia , Proteínas Virais/genéticaRESUMO
CONTEXT: E-cadherin (E-CD) is an important cell adhesion molecule in normal epithelial cells and has been shown to be an invasion tumor suppressor gene. MATERIALS AND METHODS: Various clinicopathological parameters like age, family history, tumor stage, histological grade, lymph node status and other biological markers were also analyzed. Present study reveals E-CD expression in 65 cases of breast cancer including 41 (63%) cases of pure infiltrating ductal carcinoma (IDC), 11 (16.9%) of pure infiltrating lobular carcinoma (ILC); another 10 (15.3%) of mixed ductal/lobular type, and remaining 3 (4.6%) miscellaneous types. RESULTS: Negative E-CD expression was noticed more in advancing age groups (P = 0.01). About 59.2% cases showing negative E-CD expression had family history of breast and/or other cancers. E-CD expression was found significantly higher in cases of pure IDC (55.5%) than in pure ILC cases (18.1%) (P = 0.04). Eleven (68.7%) of the total 16 high-grade IDC cases, revealed negative expression. Both cases of comedo carcinoma revealed negative expression. Three (30%) out of 10 mixed cases revealed negative expression in both ductal and lobular areas, while in remaining 7 cases, positvity was seen in ductal areas only. Invasive cribriform and medullary carcinoma revealed a stronger expression, while negative staining was observed in sweat gland carcinoma. E-CD re-expression was noticed in lymph node tumor deposits. A direct association of E-CD expression with ER expression and an inverse association with that of p53 were also observed (P = 0.001), (P = 0.04). CONCLUSIONS: E-CD expression is useful, but limited, in differentiating IDCs from ILCS. Its negative expression correlates with certain poor prognostic parameters reflecting its use as a marker for invasive cancers. It re-expresses at metastatic sites.
RESUMO
BACKGROUND: Vitamin D (1,25-dihydroxyVitamin D3) has shown experimentally anticarcinogenic effects and is thought to protect against breast cancer. The actions of Vitamin D are mediated via the Vitamin D receptor (VDR), and the polymorphisms at 3'UTR region of this gene are associated with the risk and progression of breast carcinoma. The current study is an attempt to examine the association of these variations with breast cancer risk in north Indians. METHODS: A total of 160 cases and 140 control subjects were studied for the polymorphisms at 3' end of the VDR gene. A polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) method and fragment analysis was performed to determine ApaI and TaqI polymorphisms and variable length poly-A microsatellite repeats. Linkage disequilibrium (LD) was calculated for each pair of polymorphisms. Unadjusted and adjusted odds ratios for breast cancer with genotypes comprising the polymorphic sites were calculated to understand their role towards breast cancer susceptibility. RESULTS: Patient's with long poly-A repeat showed a significant association with disease (chi 2 = 9.52, df = 2, P Assuntos
Neoplasias da Mama/genética
, Carcinoma/genética
, Polimorfismo de Fragmento de Restrição
, Receptores de Calcitriol/genética
, Regiões 3' não Traduzidas/genética
, Adolescente
, Adulto
, Idoso
, Neoplasias da Mama/epidemiologia
, Neoplasias da Mama/patologia
, Carcinoma/epidemiologia
, Carcinoma/patologia
, Estudos de Casos e Controles
, Feminino
, Frequência do Gene
, Predisposição Genética para Doença
, Genótipo
, Haplótipos
, Humanos
, Índia/epidemiologia
, Desequilíbrio de Ligação
, Modelos Logísticos
, Repetições de Microssatélites
, Pessoa de Meia-Idade
, Estadiamento de Neoplasias
, Razão de Chances
, Índice de Gravidade de Doença
, Adulto Jovem
Assuntos
Metabolismo , Fenômenos Fisiológicos da Nutrição , Cirurgia Bariátrica , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Humanos , Obesidade Mórbida/metabolismo , Obesidade Mórbida/fisiopatologia , Obesidade Mórbida/cirurgiaRESUMO
BACKGROUND: Family tracing is a method recognized to find new patients with familial hypercholesterolaemia (FH). We have implemented family tracing led by FH Nurses and have determined acceptability to patients, feasibility and costs. METHODS: Nurses were located at five National Health Service (NHS) Trusts; they identified FH patients and offered them family tracing. Responses and test results were recorded on a database and summarized on a family pedigree. RESULTS: The majority ( approximately 70%) of index cases participated; the proportion was lower when patients had been discharged from the clinics and in metropolitan areas. On average, 34% (range 13-50%) of relatives lived outside the catchment area of the clinics and could not attend the nurse-led FH clinics. Of the previously untested relatives, 76% who lived in the catchment area of the clinic came forward to be tested. One-third of the relatives who came forward for testing were children Assuntos
Hiperlipoproteinemia Tipo II/diagnóstico
, Programas de Rastreamento/economia
, Programas de Rastreamento/métodos
, Auditoria Médica/economia
, Auditoria Médica/métodos
, Projetos Piloto
, Adolescente
, Adulto
, Criança
, Pré-Escolar
, Análise Custo-Benefício
, Feminino
, Humanos
, Hiperlipoproteinemia Tipo II/epidemiologia
, Masculino
, Pessoa de Meia-Idade
, Linhagem
, Reino Unido
, Adulto Jovem
RESUMO
BACKGROUND: Familial hypercholesterolaemia (FH) is an autosomal co-dominant disorder which is relatively common, leads to high levels of LDL-cholesterol and if untreated to early coronary heart disease. An audit of current practice at National Health Service Trusts in England was undertaken to determine whether FH patients meet the diagnostic criteria for FH; are being offered appropriate advice and treatment; and to what extent their families are contacted and offered testing for the disorder. METHODS: Medical records of known FH patients (over 18 years of age and diagnosed before 31 December 2003) were accessed to obtain information on diagnosis, treatment and family tracing. RESULTS: The records of 733 FH patients were examined, 79% met the UK 'Simon Broome' register criteria for the diagnosis of definite or possible FH. Analyses showed that patients were usually offered appropriate advice and treatment, with 89% being on a statin. However, the audit indicated a high variability in family tracing between the sites, with significant differences in the frequency of inclusion of a family pedigree in the notes (range 1-71%, mean 35%); the general practitioner (GP) being advised that first-degree relatives should be tested (range 4-52%, mean 27%); and the proportion of relatives contacted and tested (range 6-50%, mean 32%). CONCLUSION: FH patients are well cared for in lipid clinics in England, are being given appropriate lifestyle advice and medication, but an increase in recording of LDL-cholesterol levels may lead to improvements in their management. Practice in family tracing appears to vary widely between clinics.
Assuntos
Hiperlipoproteinemia Tipo II/diagnóstico , Auditoria Médica , Instituições de Assistência Ambulatorial , LDL-Colesterol/sangue , Inglaterra , Feminino , Humanos , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/terapia , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Médicos de FamíliaRESUMO
PURPOSE: To determine the role of enteric fever in ileal perforations. METHODS: A prospective cohort of 47 patients of ileal perforation was subjected to clinical examination and investigations for APACHE II scoring. Blood, ulcer edge biopsy, mesenteric lymph node and peritoneal aspirate were subjected to culture to determine the predominant aerobic bacterial isolate and its antibiogram. RESULTS: Seven patients (14.9%) required intensive care and seven (14.9%) developed septicaemia. Mortality was 17%. Highest isolation rate was seen in ulcer edge (70.2%) followed by lymph node (66%) culture. The bacterial spectrum was Escherichia coli (23.4%), Enterococcus faecalis (21.3%), Salmonella enterica serovar Typhi (6.3%), Salmonella enterica serovar Paratyphi A (4.2%), etc. CONCLUSIONS: Enteric fever organisms are not the predominant causative agents of ileal perforations. Culture of ulcer edge biopsy, lymph node is crucial for aetiological diagnosis. The use of APACHE II triaging and prescription of antimicrobials based on the local pattern of susceptibility profile of the aetiological agent is recommended.
Assuntos
Infecções por Enterobacteriaceae/complicações , Doenças do Íleo/microbiologia , Perfuração Intestinal/microbiologia , APACHE , Adolescente , Adulto , Sangue/microbiologia , Enterobacteriaceae/isolamento & purificação , Feminino , Humanos , Linfonodos/microbiologia , Masculino , Pessoa de Meia-Idade , Peritônio/microbiologia , Sepse/microbiologia , Úlcera/microbiologiaRESUMO
Aflatoxins are toxic and carcinogenic polyketide metabolites produced by fungal species, including Aspergillus flavus and A. parasiticus. The biosynthesis of aflatoxins is modulated by many environmental factors, including the availability of a carbon source. The gene expression profile of A. parasiticus was evaluated during a shift from a medium with low concentration of simple sugars, yeast extract (YE), to a similar medium with sucrose, yeast extract sucrose (YES). Gene expression and aflatoxins (B1, B2, G1, and G2) were quantified from fungal mycelia harvested pre- and post-shifting. When compared with YE media, YES caused temporary reduction of the aflatoxin levels detected at 3-h post-shifting and they remained low well past 12 h post-shift. Aflatoxin levels did not exceed the levels in YE until 24 h post-shift, at which time point a tenfold increase was observed over YE. Microarray analysis comparing the RNA samples from the 48-h YE culture to the YES samples identified a total of 2120 genes that were expressed across all experiments, including most of the aflatoxin biosynthesis genes. One-way analysis of variance (ANOVA) identified 56 genes that were expressed with significant variation across all time points. Three genes responsible for converting norsolorinic acid to averantin were identified among these significantly expressed genes. The potential involvement of these genes in the regulation of aflatoxin biosynthesis is discussed.
Assuntos
Aflatoxinas/biossíntese , Antraquinonas/metabolismo , Aspergillus/metabolismo , Aflatoxinas/genética , Análise de Variância , Aspergillus/genética , Meios de Cultura/química , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Monossacarídeos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase/métodos , Sacarose/metabolismoRESUMO
Aflatoxins (AFs) are carcinogenic secondary metabolites of Aspergillus parasiticus. In previous studies, non-toxigenic A. parasiticus sec- (for secondary metabolism negative) variants were generated through serial transfer of mycelia from their toxigenic sec+ (for secondary metabolism positive) parents for genetic and physiological analysis for understanding regulation of AF biosynthesis. Previous studies have shown no difference in the DNA sequence of aflR, a positive regulator of AF production, in the sec+ and sec- strains. In this study, AflJ, another positive regulator of AF production, laeA, a global regulator of secondary metabolism, and the intergenic region between aflR and aflJ, were analysed to determine if they play a role in establishment of the sec- phenotype. The study showed that while this sequence identity extended to the aflJ as well as the aflJ-aflR intergenic region, expression of aflR in the sec- strain was several fold lower than that observed in the sec+ strain, while aflJ expression was barely detectable in the sec- strain. Western blot analysis indicated that despite AflR protein being present in the sec- strain, no toxin production resulted. Introduction of a second copy of aflR into the sec- strain increased aflR expression, but did not restore AF production. Lastly, reverse transcription-PCR analysis revealed that laeA was expressed in both sec+ and sec- strains. These results suggest that although aflR, aflJ and laeA are necessary for AF production, they are not sufficient. We propose that the aflR and aflJ expression may be regulated by element(s) downstream from laeA or from pathways not influenced by laeA.
Assuntos
Aflatoxinas/biossíntese , Aspergillus/genética , Regulação Fúngica da Expressão Gênica/genética , Fatores de Transcrição/genética , Aflatoxinas/genética , Aspergillus/metabolismo , Cromatografia em Camada Fina/métodos , Contaminação de Alimentos/prevenção & controle , Genes Fúngicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
The antioxidants in foods play an important role in preventing the generation of reactive oxygen species (ROS). Some of the dietary constituents, commonly used in Indian foods such as cloves (Syzygium aromaticum), licorice (Glycyrrhiza glabra), mace (aril of Myristica fragrans) and greater cardamom (Amomum subulatum), were selected as the test samples to find their effect on the inhibition of lipid peroxidation (LPO) in rat liver homogenate. Three different oxidant systems were used to induce LPO. The results show that all the spices have antioxidant activities at various concentrations. None of the spices showed prooxidant properties. The effect of spices on the inhibition of LPO was concentration dependent. Cloves, mace and cardamom inhibited the initiation as well as propagation phases of FeCl_{3} induced LPO, while licorice inhibited the initiation phase only. The reducing power and the superoxide scavenging activity of spices was also measured in vitro. The reducing power of various spices increased with concentration. The percentage inhibition of superoxide radical generation by the spices was also observed to be concentration dependent. The results show that spices used in the present study have significant ability to inhibit LPO due to their polyphenol content, strong reducing power and superoxide radical scavenging activity. Cloves showed the highest antioxidant activity probably due to the higher polyphenol content as compared to other spices.
Assuntos
Antioxidantes/farmacologia , Ferro/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Especiarias , Amomum , Animais , Feminino , Flavonoides/análise , Glycyrrhiza , Masculino , Myristica , Fenóis/análise , Polifenóis , Ratos , Ratos Wistar , SyzygiumRESUMO
The generation of free radicals is a cause of many pathological conditions like diabetes mellitus, cancer, stroke, etc. Free radicals cause damage to cellular DNA and initiate carcinogenesis. Free radicals also bring about proliferation of cells via cell signaling. An inverse relationship between the consumption of vegetable diets and the risk of cancer has been established. In the present study, Star anise (Illicium verum), which is a commonly used condiment in Indian cuisine, was assessed for its anti-carcinogenic potential in N-nitrosodiethylamine (NDEA) initiated and phenobarbital (PB) promoted hepato-carcinogenesis. Rats were randomly selected for eight experimental groups. The carcinogenesis was induced by injecting the rats, with a single dose of NDEA (200mg/kg body weight) intraperitoneally as initiator, followed by promotion with PB (0.05%) in drinking water for 14 consecutive weeks. The treatment with NDEA increased liver weight, while Star anise (Star) treatment reduced the liver weight of rats. The treatment with Star throughout for 20 weeks or during the promotion stage (6-20 weeks) significantly reduced the nodule incidence and nodule multiplicity in the rats, while the treatment with Star at the initiation phase (first 4 weeks) only could not reduce these parameters. The treatment with Star for 20 consecutive weeks significantly reduced the nodule size and nodule volume. The treatment with Star throughout as well as at the promotion stage lowered the lipid peroxidation (LPO) in liver and erythrocytes, while the LPO was not lowered, when Star was administered during initiation stage only. The treatment with Star restored the liver and erythrocyte super-oxide dismutase (SOD) activities to normal in the carcinogenesis-induced rats. The liver catalase (CAT) activity increased in all the treated groups. The erythrocyte CAT activity increased in the rats treated with Star during initiation and promotion stage only. The liver glutathione (GSH) level increased significantly in the groups treated with Star. The erythrocyte GSH level was lowered in the rats treated with NDEA and PB, however, Star treatment helped in increasing the erythrocyte GSH level to some extent. The liver and erythrocyte glutathione-S-transferase (GST) activity increased in all the groups treated with NDEA and PB. The treatment with Star decreased GST level significantly. These results indicate that the treatment with Star reduces the tumor burden, lowers oxidative stress and increases the level of phase II enzymes, which may contribute to its anti-carcinogenic potential.
Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Dietilnitrosamina/toxicidade , Illicium/química , Neoplasias Hepáticas Experimentais/prevenção & controle , Fenobarbital/toxicidade , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos WistarRESUMO
Programmed cell death during senescence in plants is associated with proteolysis that helps in remobilization of nitrogen to other growing tissues. In this paper, we provide one of the few reports for the expression of specific serine proteases during senescence associated proteolysis in Gladiolus grandiflorus flowers. Senescence in tepals, stamens and carpels results in an increase in total protease activity and a decrease in total protein content. Of the total protease activity, serine proteases account for about 67-70% while cysteine proteases account for only 23-25%. In-gel assays using gelatin as a substrate and specific protease inhibitors reveal the enhanced activity of two trypsin-type serine proteases of sizes 75 kDa and 125 kDa during the course of senescence. The activity of the 125 kDa protease increases not only during tepal senescence but also during stamen and carpel senescence indicating that it is responsive to general senescence signals.
Assuntos
Senescência Celular , Magnoliopsida/enzimologia , Proteínas de Plantas/metabolismo , Serina Endopeptidases/metabolismo , Apoptose , Flores/enzimologia , Flores/crescimento & desenvolvimento , Magnoliopsida/crescimento & desenvolvimento , Proteínas de Plantas/genética , Serina Endopeptidases/genética , Regulação para CimaRESUMO
Aflatoxins are toxic and carcinogenic secondary metabolites produced by the fungi Aspergillus flavus and Aspergillus parasiticus. To better understand the molecular mechanisms that regulate aflatoxin production, the biosynthesis of the toxin in A. flavus and A. parasticus grown in yeast extract sucrose media supplemented with 50 mM tryptophan (Trp) were examined. Aspergillus flavus grown in the presence of 50 mM tryptophan was found to have significantly reduced aflatoxin B(1) and B(2) biosynthesis, while A. parasiticus cultures had significantly increased B(1) and G(1) biosynthesis. Microarray analysis of RNA extracted from fungi grown under these conditions revealed 77 genes that are expressed significantly different between A. flavus and A. parasiticus, including the aflatoxin biosynthetic genes aflD (nor-1), aflE (norA), and aflO (omtB). It is clear that the regulatory mechanisms of aflatoxin biosynthesis in response to Trp in A. flavus and A. parasiticus are different. These candidate genes may serve as regulatory factors of aflatoxin biosynthesis.
Assuntos
Aflatoxinas/biossíntese , Aminoácidos/farmacologia , Aspergillus flavus/efeitos dos fármacos , Aspergillus/efeitos dos fármacos , Aspergillus/genética , Aspergillus/metabolismo , Aspergillus flavus/genética , Aspergillus flavus/metabolismo , Cromatografia Líquida de Alta Pressão , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Espectrometria de Massas , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sacarose/farmacologia , Triptofano/farmacologiaRESUMO
A single T > C change at the 5' promoter region of the CYP17 gene is reported to be associated with increased risk of breast cancer. This study evaluates the influence of genetic polymorphism of CYP17 on breast cancer susceptibility. Two hundred and forty-two patients with histopathologically confirmed breast cancer and 212 age-matched controls were included in the present study. Information relating to age at onset of the disease, family history and estrogen receptor status was elicited. Investigation for CYP17 polymorphism was carried out in 106 early onset, 80 late onset and 56 familial cases. The frequencies of two CYP17 alleles were also analyzed in 116 (47.9%) cases with known estrogen receptor (ER) status confirmed immunohistochemically. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to detect the polymorphism, and the genotypes identified were assigned as homozygous wild type (A1A1), heterozygous variant (A1A2), and homozygous variant (A2A2). Associations between the various genotypes in patients and controls were investigated with Fisher's exact test. All the tests were two tailed. The results showed that the frequency of heterozygous and homozygous CYP17 genotype was higher in early onset breast cancer patients (94.3%) than in controls (80.3%), and the difference was significant (P = 0.001). A highly statistically significant increased risk in carriers of homozygous A2 allele was found in young patients (P < or = 0.001) in comparison with patients having late onset condition (P = 0.260). However, no significant association between the genotype and breast cancer risk was observed among women with strong family history. Further, data had showed that patients (80.6%) with at least one A2 allele tended to exhibit ER-independent cell proliferation, although statistical significance could not be established (P = 0.160). The present findings suggest that CYP17 A2 allele gene polymorphism might play a significant role in breast cancer development in young Indian women.
Assuntos
Neoplasias da Mama/genética , Polimorfismo Genético/genética , Esteroide 17-alfa-Hidroxilase/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de RiscoRESUMO
The causes of the excess coronary heart disease (CHD) risk in South Asian migrants from the Indian subcontinent remain unclear. Comparisons of CHD risk factors amongst South Asian migrants living in Britain with those of the general UK population provide only a partial explanation. We compared Gujaratis in Britain with similar, non-migrant Gujaratis in India, to test the hypothesis that differences in CHD risk factors associated with migration would be more informative. Randomly sampled Gujaratis aged 25-79 years living in Sandwell (n = 242) were compared with age-, gender- and caste-matched contemporaries remaining in their villages of origin in Navsari, India (n = 295). Lifestyle indices, food intake and physical activity, were assessed with standardised questionnaires and energy expenditure and metabolic parameters measured. British Gujaratis had higher, mean body mass indices by 6 (4.5-7.4) kg/m(2) mean (95% CI), and greater dietary energy intake, fat intake, blood pressure, fasting serum cholesterol, apolipoprotein B, triglycerides, non-esterified fatty acid (NEFA) and C-reative protein concentrations than Gujaratis in India. Dietary folate and serum folate and Vitamin B(12) were lower and plasma homocysteine was higher in India. Smoking was less prevalent and high-density lipoprotein cholesterol tended to be higher in Britain. Diabetes prevalence was high in both populations and impaired fasting or 2 h post-glucose challenge plasma glucose was even more prevalent in Gujarat. In India, however, where insulin secretion and NEFA were lower diabetes and impaired glucose tolerance were less frequently accompanied by excess metabolic CVD risk factors. In conclusion, exposure to increased fat intake and obesity related to migration is likely to explain the disproportionate combination of established and emerging CHD risk factors prevalent in Gujaratis in Britain. Strategies to improve nutrition and to identify and treat cardiovascular risk factors such as dyslipidaemia and hypertension are urgently required.
Assuntos
Doença das Coronárias/etnologia , Emigração e Imigração , Adulto , Idoso , Antropometria , Doença das Coronárias/epidemiologia , Doença das Coronárias/etiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/etnologia , Dieta , Inglaterra/epidemiologia , Exercício Físico , Comportamentos Relacionados com a Saúde , Humanos , Índia/etnologia , Estilo de Vida , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
Aflatoxins are the most toxic and carcinogenic naturally occurring mycotoxins. They are produced primarily byAspergillus flavus andA. parasiticus. In order to better understand the molecular mechanisms that control aflatoxin production, identification of genes usingA. flavus expressed sequence tags (ESTs) and microarrays is currently being performed. Sequencing and annotation ofA. flavus ESTs from a normalizedA. flavus cDNA library identified 7,218 unique EST sequences. Genes that are putatively involved in aflatoxin biosynthesis, regulation and signal transduction, fungal virulence or pathogenicity, stress response or antioxidation, and fungal development were identified from these ESTs. Microarrays containing over 5,000 uniqueA. flavus gene amplicons were constructed at The Institute for Genomic Research. Gene expression profiling under aflatoxin-producing and non-producing conditions using this microarray has identified hundreds of genes that are potentially involved in aflatoxin production. Further investigations on the functions of these genes by gene knockout experiments are underway. This research is expected to provide information for developing new strategies for controlling aflatoxin contamination of agricultural commodities.
RESUMO
Aspergillus flavus is a plant and animal pathogen that also produces the potent carcinogen aflatoxin. Aspergillus oryzae is a closely related species that has been used for centuries in the food fermentation industry and is Generally Regarded As Safe (GRAS). Whole genome sequences for these two fungi are now complete, providing us with the opportunity to examine any genomic differences that may explain the different ecological niches of these two fungi, and perhaps to identify pathogenicity factors in A. flavus. These two fungi are very similar in genome size and number of predicted genes. The estimated genome size (36·8 Mb) and predicted number of genes (12â197) for A. flavus is similar to that of A. oryzae (36·7 Mb and 12â079, respectively). These two fungi have significantly larger genomes than Aspergillus nidulans (30·1) and Aspergillus fumigatus (29·4). The A. flavus and A. oryzae genomes are enriched in genes for secondary metabolism, but do not differ greatly from one another in the predicted number of polyketide synthases, nonribosomal peptide synthases or the number of genes coding for cytochrome P450 enzymes. A micro-scale analysis of the two fungi did show differences in DNA correspondence between the two species and in the number of transposable elements. Each species has approximately 350 unique genes. The high degree of sequence similarity between the two fungi suggests that they may be ecotypes of the same species and that A. oryzae has resulted from the domestication of A. flavus.
RESUMO
OBJECTIVES: Exact categorization of soft tissue tumours (STTs) on smears requires application of various ancillary techniques. This study was aimed at evaluating the role of fluorescent immunocytochemistry (FICC) in cyto-diagnosis of 30 STT cases. METHODS: Thirty cases of soft tissue tumours were included in the present study. All cases were subjected to routine Giemsa and Papanicolaou stain. Extra smears were made and kept for fluorescent immunostaining. A panel of cytoskeletal antibodies, tagged with FITC (Fluorescein isothyocynate), was employed in all these cases. Fluorescent immunostained smears were examined under Zeiss Confocal Laser scanning microscope, using double immunofluorescence (red-green). Finally, all cases were subjected to biopsy and again immunoperoxidase staining. RESULTS: Among the 30 cases in the present study, unaided cytological diagnoses ranged from 'spindle cell' tumour in four (13.3%) cases, benign and malignant spindle cell tumour in 17 (56.6%) cases, to malignant mesenchymal tumour in nine (30%) cases. FICC helped in further correct categorization of 25/30 (83.3%) cases viz. leiomyoma (three), benign neurogenic tumour (six), schwannoma (one), dermatofibrosarcoma protuberans (three), synovial sarcoma (two), rhabdomyosarcoma (two), malignant fibrous histiocytoma (five) and malignant peripheral nerve sheath tumour (three). Aggressive fibromatosis was found to be a missed diagnosis in two cases. Overall concordance between cyto-diagnosis with FICC, and histopathology results was 83.3% (P < 0.05). CONCLUSION: Fluorescent immunocytochemistry is a significant ancillary technique for making a rapid and specific diagnosis of STT, as required for their timely management. Incorporation of a wide panel of antibody markers with clinico-cytological correlation is recommended in forming an exact diagnosis in these cases.