RESUMO
Recently genome-wide association studies on East Asian populations reported an association between diabetes and several single nucleotide polymorphisms (SNPs) in a 40-kb linkage disequilibrium block in intron 15 of KCNQ1. However, the association between KCNQ1 variants and type 2 diabetes mellitus (T2DM) in Chinese Kazakh populations is unknown. We investigated the relationship between rs2237892 and rs2237895 SNPs in KCNQ1 and susceptibility to and clinical characteristics of T2DM in 100 Chinese Kazakh T2DM subjects and 100 healthy subjects. SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism and the main anthropometric and biochemical parameters of individuals were assessed in the genotype groups (rs2237892: CC, CT, or TT, and rs2237895: AA, AC, or CC). Genotype distribution and allele frequencies of these two SNPs were not significantly different between T2DM and control groups (P > 0.05). The frequencies of CT and TT genotypes and T allele for the rs2237892 SNP in females with T2DM were significantly higher than that in the control group (genotype: P = 0.016, allele: P = 0.004). However, there were no significant differences among individuals with different genotypes with respect to the rs2237895 SNP (P > 0.05). The main anthropometric and biochemical parameters did not correlate with the rs2237892 or rs2237895 SNPs in the T2DM group (P > 0.05). Thus, the T allele-containing genotypes of the rs2237892 SNP in KCNQ1 may increase the susceptibility to T2DM in female Chinese Kazakh individuals, whereas the rs2237895 SNP may not be associated with T2DM in the Chinese Kazakh population.
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Canal de Potássio KCNQ1/genética , Adulto , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , China , Diabetes Mellitus Tipo 2/genética , Etnicidade/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genética Populacional , Humanos , Canal de Potássio KCNQ1/metabolismo , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
INTRODUCTION: Cardiovascular diseases are the main cause of morbidity and mortality in Malaysia. There is evidence of high traditional and complementary medicine (TCM) use among population with cardiovascular risk and there have been anecdotal reports about substitution of conventional medicines with TCM. We investigated the prevalence of TCM use, treatment preference and substitution of conventional medicines in study population with cardiovascular risk factors in Pahang, Malaysia. METHODS: A cross-sectional survey was conducted using an interviewer-administered questionnaire in five districts of Pahang. A total of 1250 households were chosen through proportionate and systematic sampling. Respondents aged 18 years and above were selected. RESULTS: The study population with cardiovascular risk factors who used TCM was higher than the general population (31.7% versus 25.9%). There were no clear preferences in using TCM by gender, age groups, educational level and income even though other bumiputeras showed a slight inclination towards TCM use. Among the study population with cardiovascular risk factors who consumed TCM, 20-30% of them were using TCM as a substitute for their conventional medications. Respondents from the younger age group (18-40 years) (57.1%), highest educational level (43.2%), other bumiputeras (38.4%) and highest income group (31.4%) preferred the combination of both conventional and traditional medicine. CONCLUSION: TCM use among population with cardiovascular risk factors is high. The high preference for combination therapy of TCM and conventional medications among young adults and the use of TCM to substitute conventional medications show that much research is needed to provide proven TCM therapies to avoid self-mismanagement of cardiovascular risk in Malaysia.
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Transgenic rhesus monkeys carrying the green fluorescent protein (GFP) gene were produced by injecting pseudotyped replication-defective retroviral vector into the perivitelline space of 224 mature rhesus oocytes, later fertilized by intracytoplasmic sperm injection. Of the three males born from 20 embryo transfers, one was transgenic when accessible tissues were assayed for transgene DNA and messenger RNA. All tissues that were studied from a fraternal set of twins, miscarried at 73 days, carried the transgene, as confirmed by Southern analyses, and the GFP transgene reporter was detected by both direct and indirect fluorescence imaging.
Assuntos
Animais Geneticamente Modificados , Técnicas de Transferência de Genes , Transferência Genética Horizontal , Proteínas Luminescentes/genética , Macaca mulatta/genética , Animais , Animais Recém-Nascidos , Southern Blotting , Transferência Embrionária , Desenvolvimento Embrionário e Fetal , Feminino , Imunofluorescência , Expressão Gênica , Vetores Genéticos , Proteínas de Fluorescência Verde , Masculino , Vírus da Leucemia Murina de Moloney/genética , Oócitos , Reação em Cadeia da Polimerase , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas , TransgenesRESUMO
The effects of thermosonication on the quality of a stingless bee honey, the Kelulut, were studied using processing temperature from 45 to 90 â and processing time from 30 to 120 minutes. Physicochemical properties including water activity, moisture content, color intensity, viscosity, hydroxymethylfurfural content, total phenolic content, and radical scavenging activity were determined. Thermosonication reduced the water activity and moisture content by 7.9% and 16.6%, respectively, compared to 3.5% and 6.9% for conventional heating. For thermosonicated honey, color intensity increased by 68.2%, viscosity increased by 275.0%, total phenolic content increased by 58.1%, and radical scavenging activity increased by 63.0% when compared to its raw form. The increase of hydroxymethylfurfural to 62.46 mg/kg was still within the limits of international standards. Optimized thermosonication conditions using response surface methodology were predicted at 90 â for 111 minutes. Thermosonication was revealed as an effective alternative technique for honey processing.
Assuntos
Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Mel/análise , Temperatura Alta , Sonicação/métodos , Animais , Abelhas , Fenômenos Químicos , Cor , Fenóis , ViscosidadeRESUMO
Inappropriate c-MET signaling in cancer can enhance tumor cell proliferation, survival, motility, and invasion. Inhibition of c-MET signaling induces apoptosis in a variety of cancers. It has also been recognized as a novel anticancer therapy approach. Furthermore, reports have also indicated that constitutive expression of P-glycoprotein (ABCB1) is involved in the HGF/c-MET-related pathway of multidrug resistance ABCB1-positive human hepatocellular carcinoma cell lines. We previously reported that elevated expression levels of PKCδ and AP-1 downstream genes, and HGF receptor (c-MET) and ABCB1, in the drug-resistant MES-SA/Dx5 cells. Moreover, leukemia cell lines overexpressing ABCB1 have also been shown to be more resistant to the tyrosine kinase inhibitor imatinib mesylate. These findings suggest that chemoresistant cancer cells may also develop a similar mechanism against chemotherapy agents. To circumvent clinical complications arising from drug resistance during cancer therapy, the present study was designed to investigate apoptosis induction in ABCB1-overexpressed cancer cells using c-MET-targeted RNA interference technology in vitro and in vivo. The results showed that cell viability decreased and apoptosis rate increased in c-MET shRNA-transfected HGF/c-MET pathway-positive MES-SA/Dx5 and MCF-7/ADR2 cell lines in a dose-dependent manner. In vivo reduction of tumor volume in mice harboring c-MET shRNA-knockdown MES-SA/Dx5 cells was clearly demonstrated. Our study demonstrated that downregulation of c-MET by shRNA-induced apoptosis in a multidrug resistance cell line.
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Proteínas Proto-Oncogênicas c-met/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Animais , Apoptose/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos , Feminino , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas c-met/deficiência , Proteínas Proto-Oncogênicas c-met/metabolismo , Sarcoma/tratamento farmacológico , Sarcoma/genética , Sarcoma/metabolismo , Sarcoma/patologia , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
We describe here a simple and rapid method for enzymatic DNA amplification using DNA template recovered from membrane filters previously used in hybridization analysis. This is done by first solubilizing membrane pieces carrying DNA of interest in dimethyl sulfoxide, followed by isopropanol precipitation and polymerase chain reaction amplification. The source of membrane-bound DNA successfully tested includes plasmid and human leukocyte DNA and DNA immobilized on bacterial colony filters and plaque lifts. The sensitivity of the procedure is such that DNA recovered from 0.5 microgram of filter-bound total human DNA was enough for PCR amplification of a 0.3-kb fragment. Our protocol will be useful for recycling of scarce DNA samples for cloning and sequencing purposes.
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DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Biotecnologia , Dimetil Sulfóxido , Escherichia coli/genética , Estudos de Avaliação como Assunto , Filtração , Amplificação de Genes , Hibridização de Ácido NucleicoRESUMO
It is important to know the effects of anaesthetics on cerebral blood flow and cerebral metabolism to enable appropriate selection of agents for the brain injured patient. Thiopental possesses favourable cerebrovascular and metabolic properties but has not been shown to improve outcome in head injured patients. Propofol has properties similar to thiopental. Its rapid metabolism as well as its ability to reduce intracranial pressure and its antiemetic properties render it a very favourable drug. Despite controversies surrounding the effects of short-acting narcotics on intracranial pressure, they continue to be used because they provide stable haemodynamic conditions when used with care. Isoflurane is currently advocated as the best inhalational agent for neuroanaesthesia because of its lesser effects on cerebral blood flow and intracranial pressure. The effects of nitrous oxide on cerebral blood flow and intracranial pressure appear to vary according to the background anaesthetic used. Nitrous oxide is still widely used in most neuroanaesthetic practices, as its effects can be blunted by barbiturates, narcotics and/or hypocapnia. There is no convincing human study on the cerebral protective properties of anaesthetic agents although mild hypothermia has been shown experimentally to offer significant protection against global and focal ischaemia.
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Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos/farmacologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/fisiopatologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Humanos , Pressão Intracraniana/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacosRESUMO
Previous biochemical and structural studies using established cell lines have led to a hypothesis that the cellular p53 and the retinoblastoma susceptibility (Rb) proteins may play a crucial role in the pathogenesis process of cervical carcinoma. To further test this hypothesis, we have analyzed the structure of the p53 and Rb genes in 38 primary cervical carcinoma samples with known HPV status using the polymerase chain reaction-based single-strand conformation polymorphism (SSCP) approach. All 11 exons as well as 500 bp of the 5'-noncoding region of the p53 gene and exons 13-23 of the Rb gene were analyzed. None of these exons in all the samples analyzed showed band shift in the SSCP gel indicative of the presence of mutation. In the same experiments, however, all known exon mutations as well as previously unreported mutations in the intron sequences of the p53 and Rb genes in the HPV-free C33-A and HT-3 cell lines were detected. The absence of mutation in the p53 gene in all five HPV-negative samples was confirmed by direct sequence analysis. It appears that p53 and Rb mutations are a very rare event in cervical cancer and their occurrence is apparently not strictly correlated with HPV status.
Assuntos
Genes do Retinoblastoma , Genes p53 , Mutação , Neoplasias do Colo do Útero/genética , Sequência de Bases , Southern Blotting , China/etnologia , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Feminino , Humanos , Íntrons , Dados de Sequência Molecular , Papillomaviridae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Deleção de Sequência , Taiwan , Células Tumorais CultivadasRESUMO
This Manuscript was read at the Clinical Aspects on Dengue Fever and Dengue Hemorrhagic Fever held at Kaohsiung Medical College, Kaohsiung City, Taiwan, Republic of China, November 13, 1988. There is not enough evidence to prove that the dengue virus will cause teratogenicity, abortion, or intrauterine growth retardation of a fetus during pregnancy. Nine cases of women infected with dengue fever in early pregnancy received amniocentesis (or chorion villi sampling) in the Department of Obstetrics and Gynecology, KMCH. The chromosome analysis revealed that all were normal, and the level of alpha-fetoprotein in amniotic fluids and maternal sera were within normal range. Antibodies to the dengue virus in the dengue infected mother can cross the placenta and transfer to the fetus, which can cause new born infants to develop dengue hemorrhagic fever or dengue shock syndrome easily when they are primarily infected with dengue virus. Anti-dengue activity was found in the lipid component of human milk and colostrum. This suggests that breast feeding will protect the infant from the dengue virus in the endemic area of dengue infection.
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Dengue/complicações , Doenças Fetais/etiologia , Complicações Infecciosas na Gravidez , Aborto Espontâneo/etiologia , Adulto , Anormalidades Congênitas/etiologia , Dengue/imunologia , Feminino , Doenças Fetais/diagnóstico , Retardo do Crescimento Fetal/etiologia , Humanos , Imunidade Materno-Adquirida , Lactação , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Diagnóstico Pré-NatalRESUMO
Impaired pulmonary oxygen (O2) exchange is common during general anaesthesia but there is no clinical unanimity as to methods of prevention or treatment. We studied 14 patients at risk for pulmonary dysfunction because of increased age, obesity, cigarette smoking, or chronic lung disease. Pulmonary O2 exchange was measured during four conditions of ventilation: awake spontaneous, conventional tidal volume (CVT, 7 ml.kg-1) or high tidal volume (HVT, 12 ml.kg-1) controlled ventilation, and five min after manual hyperinflation (HI) of the lungs. The FIO2 was controlled at 0.5, and FETCO2 was kept constant by adding dead space during HVT. Eight patients were ventilated with N2O/O2 and six with air/O2. Arterial blood gases were used to calculate the (A-a)DO2. In seven patients (A-a)DO2 worsened after induction of anaesthesia, while in seven there was no change or an improvement. Manual HI significantly reduced (A-a)DO2, but changing tidal volume (VT) had no effect. Using a multivariate model to predict O2 exchange, obesity and type of surgery were significantly associated with worsening, while level of VT and inspiratory gas (N2O or N2) were not significant predictors. Thus patient and surgical factors were more important determinants of pulmonary gas exchange during anaesthesia than were tidal volume or inspiratory gas. Manual HI is a simple and effective manoeuvre to improve gas exchange.
Assuntos
Anestesia Geral , Pulmão/fisiopatologia , Oxigênio/sangue , Troca Gasosa Pulmonar/fisiologia , Respiração Artificial/métodos , Volume de Ventilação Pulmonar/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia , Dióxido de Carbono/sangue , Dióxido de Carbono/metabolismo , Humanos , Ventilação com Pressão Positiva Intermitente , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Oxigênio/administração & dosagem , Pressão Parcial , Fatores de TempoRESUMO
Impaired pulmonary gas exchange is a common complication of general anaesthesia. Periodic hyperinflation of the lungs and large tidal volume ventilation were the first preventive measures to be widely embraced, but their effectiveness in clinical practice has never been clearly established by controlled clinical studies. To assess their effects in high-risk patients we studied 24 adults having lower abdominal gynaecological surgery in the Trendelenburg (head down) position. Pulmonary oxygen exchange was determined during four steady-states: awake control (AC), after 30 min of conventional tidal volume (CVT, 7.5 ml.kg-1) or high tidal volume (HVT, 12.7 ml.kg-1) ventilation, introduced in random order, and five minutes after manual hyperinflations (HI) of the lungs. The patients' lungs were ventilated with air/O2 by an Ohmeda volume-controlled ventilator via a circle system. The FIO2 was controlled at 0.5, and FETCO2 was controlled by adding dead space during HVT. Arterial blood gas analysis was used to calculate the oxygen tension-based indices of gas exchange. There was significant deterioration of (A-a)DO2 at 30 min in Group A, whose lungs were first ventilated with CVT (81.6 +/- 7.2 to 166.8 +/- 13.7 mmHg, P less than 0.001); but not in Group B, whose lungs were first ventilated with HVT (77.0 +/- 9.9 to 104.4 +/- 16.8 mmHg). When Group A and B data were pooled there was no difference between randomized CVT and HVT, but improvement occurred after HI. In this model of compromised O2 exchange large inflation volumes (HVT and HI) were of considerable clinical benefit, HVT prevented and HI reversed the gas exchange disorder.
Assuntos
Abdome/cirurgia , Troca Gasosa Pulmonar , Respiração Artificial/métodos , Volume de Ventilação Pulmonar , Adulto , Analgesia Epidural , Anestesia Intravenosa , Dióxido de Carbono/análise , Feminino , Humanos , Ventilação com Pressão Positiva Intermitente/métodos , Pessoa de Meia-Idade , Oxigênio/análise , Oxigênio/sangue , Postura , Mecânica Respiratória , Fatores de Tempo , Capacidade Pulmonar TotalRESUMO
A double-blind study was undertaken to investigate the effect of prewarmed local anaesthetic solution on the latency of onset of caudal blocks. Forty-four (ASA I-II) patients were allocated into two equal groups. In Group A, the local anaesthetic solutions were injected at room temperature (25 degrees C), while in Group B, they were injected at 37 degrees C. All the caudal blocks were performed using 20 ml of lignocaine 1.5% with adrenaline 1:200,000. The speed of onset of perianal analgesia was found to be significantly faster (39%) with the prewarmed local anaesthetic solution (P < 0.05). No adverse effects were observed.
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Anestesia Caudal , Lidocaína , Adulto , Circuncisão Masculina , Cistoscopia , Método Duplo-Cego , Feminino , Hemorroidas/cirurgia , Temperatura Alta , Humanos , Masculino , Fístula Retal/cirurgiaRESUMO
We have previously reported that thermal preconditioning confers an oxidative resistance in rat heart-derived H9c2 myocytes. The development of this resistance is associated with a co-expression of both inducible (hsp70i) and constitutive (hsp70c) forms of the 70-kD heat shock proteins, suggesting an antioxidant role for these proteins. Overexpression of hsp70i has been shown to render cells more tolerant to oxidative challenge. The present study sought to determine whether increases in hsp70c, the constitutive member of this protein family, are also positively correlated to oxidative protection. A rat cDNA encoding hsp70c was inserted into a mammalian expression vector, allowing transcription of the inserted gene to be regulated by a powerful cytomegaloviral promoter. After introduction of this construct into H9c2 myocytes, stable clones were obtained. Western and Northern blot analysis of the derived clones showed a two-fold increase in hsp70c mRNA and protein concentrations. These clones were more resistant to thermal killing when compared to control cells transfected with the vector alone, implicating a functional role for the overexpressed hsp70c protein. hsp70c-enriched cells also exhibited a marked resistance to oxidative challenges, including exposure to hydrogen peroxide (H2O2), hydroxyl radical, menadione, and hypoxia/reoxygenation. These findings indicate that hsp70c overexpression provides a protective effect against endogenous or exogenously generated reactive oxygen species (ROS), suggesting that hsp70c actively participates in the heat shock-induced oxidative protection.
Assuntos
Proteínas de Choque Térmico HSP70/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Animais , Células COS , Linhagem Celular , Expressão Gênica , Proteínas de Choque Térmico HSP70/metabolismo , Coração/efeitos dos fármacos , Temperatura Alta , Peróxido de Hidrogênio/toxicidade , Precondicionamento Isquêmico Miocárdico , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Estresse Oxidativo , Ratos , Espécies Reativas de Oxigênio/metabolismo , TransfecçãoRESUMO
We have previously cloned and analyzed the structure of a type 16 human papillomavirus (HPV16) integration in a primary cervical carcinoma tissue, M50 (Choo et al., J. Virol. 62, 1659-1666, 1988). We found that specific nucleotide sequences within the HPV16 genome influenced the genomic organization of the integrated viral genome. Using the viral-cellular junctions of the M50 DNA as probes, we have now cloned the unoccupied site from a human genomic library. Mapping analysis showed that a deletion of about 1.1 kilobase pairs (kb) had occurred at the integration site of M50. Sequencing of the integration junctions of the unoccupied site and comparison with the viral sequence has revealed short regions of sequence homology between the viral and the cellular genomes at both junctions. Our results are consistent with a mechanism of integration of the HPV16 sequences in the M50 carcinoma involving illegitimate recombination events using short patches of homologous sequences between the two heterologous genomes for anchorage and as guides for crossover. Preferred topoisomerase I cleavage sites and alternating purine and pyrimidine bases, which favor the formation of Z-DNA, could also be identified at the integration regions, supporting a proposed role for the topoisomerase I enzyme in the illegitimate recombination in the viral integration process.
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Sítios de Ligação Microbiológicos , Papillomaviridae/genética , Neoplasias do Colo do Útero/microbiologia , Sequência de Bases , Clonagem Molecular , DNA Viral/química , DNA Viral/metabolismo , Feminino , Humanos , Dados de Sequência Molecular , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Células Tumorais CultivadasRESUMO
The structure of the c-myc oncogene in 17 cervical tumors and patient-matched nontumor tissues from Chinese patients residing in Taiwan was analysed. In contrast to recent reports on Mexican patients, none of the samples showed rearrangements and sequence amplification in the c-myc gene. The discrepancy may be explained by different carcinogenesis mechanisms being in operation in different geographic regions. Although no structural alterations in the c-myc gene were found in seven cervical carcinoma cell lines analysed, Northern blot analysis indicated different levels of c-myc gene expression which may be related to the presence of human papillomavirus (HPV) sequence in the cell and suggests a possible c-myc-hpv interaction in some stages of the transformation process.
Assuntos
Carcinoma de Células Escamosas/genética , Proto-Oncogenes , Neoplasias do Colo do Útero/genética , Northern Blotting , Southern Blotting , Linhagem Celular , DNA/genética , DNA de Neoplasias/genética , Feminino , Regulação da Expressão Gênica , Humanos , Hibridização de Ácido Nucleico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-myc , RNA/genética , RNA Neoplásico/genética , Valores de ReferênciaRESUMO
We compared postoperative analgesia in 15 patients (group A) who were given intraoperative epidural morphine 3 mg and lidocaine 150 mg after laminectomy/discectomy with that of 15 patients (group B) who were given only epidural lidocaine 150 mg. Epidural administration was accomplished by direct placement of the epidural catheter into the epidural space under direct vision during surgery. Eight patients (53%) in group A and 15 patients (100%) in group B required supplementary narcotics during the first 24 h postoperatively (P<0.05). The amount of supplementary narcotics given to group A patients was significantly less than that for group B (P<0.05), and the pain scores for group A patients were also significantly lower at 1, 2, and 6 h postoperatively (P<0.05). There was no difference in the observed side effects in the two groups. We conclude that postoperative pain relief following laminectomy/discectomy is superior when epidural morphine is added to lidocaine than when lidocaine is being used alone.
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We have produced a transgenic mouse (B32-1) carrying the complete genome of the human hepatitis B virus (HBV). High titers of the viral surface (HBsAg) and the e antigen (HBeAg) were detected in the serum of the mouse. In the liver and 12 of 16 extrahepatic tissues analyzed, Northern blot hybridization indicated the presence of the 2.1-kilobase (kb) and the 3.5-kb major HBV transcripts. A liver cDNA library was constructed from which the liver RNAs from four cDNA clones with splicing were found. Sequencing analysis showed that the splicing occurred between nucleotides 2451 and 487 of the viral genome, resulting in a truncated viral polymerase gene, as in human hepatocytes. Southern blot analysis of total DNA preparations of the tissues revealed the presence of episomal HBV genome, indicating replication of the viral transgenome in these tissues. However, replication was detected only in some but not all of the tissues that transcribed the 3.5-kb RNA. Partial double-stranded as well as full-length and subgenomic-length single-stranded HBV DNA species of discrete sizes were detected which may represent replication intermediates of preferred replication termination sites of the HBV transgenome. Since many molecular characteristics of mouse B32-1 were similar to those found in HBV-infected humans, HBV transgenic mice similar to B32-1 would be useful in further elucidation of other aspects of the replication and transcription mechanisms of HBV in the liver and extrahepatic tissues.
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Regulação Viral da Expressão Gênica , Vírus da Hepatite B/genética , Animais , Sequência de Bases , Northern Blotting , Southern Blotting , Sondas de DNA , DNA Viral/genética , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/imunologia , Fígado/microbiologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Splicing de RNA , RNA Mensageiro/genética , RNA Viral/genética , Radioimunoensaio , Transcrição Gênica , Replicação ViralRESUMO
Type 18 human papillomavirus (HPV18) is a genital virus closely associated with cervical carcinoma. To analyze the transcriptional activities of the long control region (LCR) of the HPV18 genome, we have produced 12 transgenic mice harboring the HPV18/LCR sequence fused to a promoterless SV40 T-antigen (TAg) gene. The mice were small in body size, generally very weak, and none lived longer than 110 days. Three mice with the longest life span (58-110 days) developed hyperplastic thymus and/or lymph node and were further analyzed. In these mice, Northern hybridization failed to detect TAg transcripts in any of the 25 organs studied. However, spliced TAg RNA was detected by polymerase chain reaction in the hyperplastic thymus and lymph node and in the normal submaxillary gland, stomach, large intestine, urinary bladder, and the cerebrum, indicating the presence of very low cellular levels of TAg RNA in these organs. When immunostaining was performed on the hyperplastic thymus, TAg protein was detected only in the ductal epithelial cells. Our results appear to indicate that the HPV18/LCR sequence was able to express only unregulated and basal levels of transcriptional activity in transgenic mice. Such a mode of transcription has become a major hindrance in the use of transgenic mouse system for the studies of the biology of the human papillomavirus.
Assuntos
Papillomaviridae/genética , Sequências Reguladoras de Ácido Nucleico , Transcrição Gênica , Sequência de Aminoácidos , Animais , Antígenos Transformantes de Poliomavirus/química , Antígenos Transformantes de Poliomavirus/genética , Sequência de Bases , Southern Blotting , Clonagem Molecular , DNA Viral , Genoma Viral , Camundongos , Camundongos Transgênicos , Dados de Sequência MolecularRESUMO
PURPOSE: Although it has been suggested that the rate at which the cerebral circulation responds to changes in PaCO2 is different with differing anesthetics, there have been no attempts to measure this. Transcranial Doppler allows the continuous measurement of cerebral blood flow velocity (CBFV) and any changes over time. Our aim was to compare the rate of change of CBFV when end-tidal CO2 (P(ET)CO2) was rapidly altered during halothane or isoflurane anesthesia. METHODS: Twenty-eight unpremedicated healthy patients were randomly assigned to receive air/O2 and either 1-1.5 MAC halothane or isoflurane as the primary anesthetic. After 15 min of steady state, P(ET)CO2 was rapidly reduced from 45 mm Hg to 30 mm Hg. CBFV and P(ET)CO2 were recorded every 30 sec for the next 10 min. RESULTS: The rate of change of normalized CBFV (delta CBFV vs. delta time) was more rapid in the isoflurane group (P <0.0001) especially in the initial few minutes. In all patients anesthetized with isoflurane, and in all but two patients anesthetized with halothane, the reduction in P(ET)CO2 produced a corresponding decrease in CBFV However, there were no differences in the magnitude of cerebrovascular CO2 reactivity (delta CBFV vs. delta P(ET)CO2) between the two groups. CONCLUSIONS: The rate of change of CBFV was faster in the isoflurane than in the halothane group especially in the initial few minutes. Indeed, for two patients in the halothane group Vmca did not change despite a change in P(ET)CO2. This may be of clinical importance when cerebrovascular tone needs to be changed rapidly.