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1.
J Med Virol ; 93(8): 5193-5198, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33974279

RESUMO

JC virus (JCV) causes progressive multifocal leukoencephalopathy in immunocompromised patients. The prevalence and genotype patterns of JCV vary between different geographical regions. This study was done to investigate the prevalence and genotype distribution of JCV in patients with hematological malignancies in Vietnam. A total of 48 urine samples were collected from patients with hematological malignancies. DNA was extracted and detection of JCV was by nested-polymerase chain reaction. Sequence analysis was obtained and a phylogenetic tree was constructed for genotyping of JCV. Twenty-seven (56.25%) urine samples tested positive for JCV. JCV genotype 7 was only observed in this study. Subtype analysis showed that JCV subtype 7A was the most commonly prevalent, followed by 7B1 and 7C1. Other subtypes were not detected in this population. There were no significant differences associated with age, gender, and biochemical parameters between patients with JCV and without JCV excretion in urine. The present study showed a high prevalence of JCV in the urine of patients with hematologic malignancies. The most common genotype found in this population was JCV subtype 7A.


Assuntos
Neoplasias Hematológicas/virologia , Vírus JC/genética , Infecções por Polyomavirus/virologia , Infecções Tumorais por Vírus/virologia , Adulto , Idoso , DNA Viral/genética , DNA Viral/urina , Feminino , Genótipo , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/urina , Humanos , Vírus JC/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Filogenia , Infecções por Polyomavirus/epidemiologia , Infecções por Polyomavirus/urina , Prevalência , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/urina , Vietnã/epidemiologia , Carga Viral
2.
Curr Pharm Biotechnol ; 22(10): 1266-1272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33213337

RESUMO

BACKGROUND: Oleanolic acid is an oleanane triterpene found in many plant species all over the world. This compound is also a major saponin in leaves of Polyscias fruticosa and possesses several promising pharmacological activities, such as hepatoprotective effects, and antiinflammatory, antioxidant, or anticancer activities. OBJECTIVE: The objective of the present work is to establish cell suspension culture of P. fruticosa, investigate the influence of several factors such as plant growth regulators and carbon source on cell growth, and determine their oleanolic acid content. METHODS: Cell culture was established by using 2 g fresh weight of 30 day old friable callus derived from in vitro stem segment in 50 mL of liquid medium with a shaking speed of 220 rpm. The culture was then incubated at 25±2ºC with a shaking speed of 120 rpm in the period of 12 h daylight at a light intensity of about 6.75 µmol/m2/s. Cell growth was measured by fresh and dry biomass at 16 h day. Oleanolic acid content was determined using HPLC analysis. RESULTS & DISCUSSION: The study results showed that MS medium containing 2% sucrose as a carbon source, supplemented with 1 mg/L 6-benzylaminopurine and 0.5 mg/L 2,4-dichlorophenoxyacetic acid was the most appropriate growth medium. Cell biomass and oleanolic acid content reached the highest values of 0.43 g dry weight/flask and 25.4 mg/g dry weight, respectively. CONCLUSION: These results indicated the potential production of oleanolic acid, a compound with high pharmacological value, from P. fruticosa cell culture.


Assuntos
Araliaceae , Ácido Oleanólico , Saponinas , Triterpenos , Técnicas de Cultura de Células , Ácido Oleanólico/farmacologia
3.
Nat Commun ; 9(1): 1139, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29556010

RESUMO

Streptomycetes are notable for their complex life cycle and production of most clinically important antibiotics. A key factor that controls entry into development and the onset of antibiotic production is the 68-residue protein, BldC. BldC is a putative DNA-binding protein related to MerR regulators, but lacks coiled-coil dimerization and effector-binding domains characteristic of classical MerR proteins. Hence, the molecular function of the protein has been unclear. Here we show that BldC is indeed a DNA-binding protein and controls a regulon that includes other key developmental regulators. Intriguingly, BldC DNA-binding sites vary significantly in length. Our BldC-DNA structures explain this DNA-binding capability by revealing that BldC utilizes a DNA-binding mode distinct from MerR and other known regulators, involving asymmetric head-to-tail oligomerization on DNA direct repeats that results in dramatic DNA distortion. Notably, BldC-like proteins radiate throughout eubacteria, establishing BldC as the founding member of a new structural family of regulators.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , Streptomyces coelicolor/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sequência de Bases , Sítios de Ligação/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Regulação Bacteriana da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Genes Bacterianos , Modelos Moleculares , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , Estrutura Quaternária de Proteína , Regulon , Sequências Repetitivas de Ácido Nucleico , Proteínas Repressoras/genética , Eletricidade Estática , Streptomyces coelicolor/genética , Streptomyces coelicolor/crescimento & desenvolvimento
4.
Rev Med Interne ; 27(11): 869-73, 2006 Nov.
Artigo em Francês | MEDLINE | ID: mdl-16949707

RESUMO

INTRODUCTION: Hypereosinophilia can cause severe cardiac complications. The association between an acute lymphoblastic leukemia and hypereosinophilia was rare. We report a case of a 29-year-old man who presented a heart failure secondary to necrotic myocarditis related to an acute eosinophilic lymphoblastic leukaemia. EXEGESIS: The patient developed a heart failure and secondary a cardio-embolic stroke, due to a large mobile left ventricle thrombosis. His peripheral blood showed a total white count of 28,500 leucocytes/mm3 with 18,800 eosinophils/mm3. The myelogram cytology showed precursor B-cell acute lymphoblastic leukaemia with hypereosinophilia. CONCLUSION: The possibility of the rapid emergence of cardiac lesions in hypereosinophilic syndromes warrants very close physician vigilance. An Echocardiography and MRI performed at the early stage and in the follow-up allow to detect and to manage these cardiac disorders.


Assuntos
Síndrome Hipereosinofílica/complicações , Leucemia Linfoide/complicações , Miocardite/etiologia , Doença Aguda , Adulto , Evolução Fatal , Insuficiência Cardíaca/etiologia , Humanos , Síndrome Hipereosinofílica/diagnóstico , Síndrome Hipereosinofílica/terapia , Leucemia Linfoide/diagnóstico , Leucemia Linfoide/terapia , Masculino , Miocardite/diagnóstico , Miocardite/terapia , Necrose , Acidente Vascular Cerebral/etiologia
5.
J Med Chem ; 35(21): 3949-55, 1992 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-1331450

RESUMO

Analogues of [Leu10]NKA4-10 were synthesized in which each of the amide bonds was sequentially replaced with the reduced amide psi (CH2NH) bond to determine the effect of this structural modification on the antagonism of NKA binding to the HUB NK2 receptor. [psi (CH2-NH)9,Leu10]NKA4-10 (6) retained significant affinity for the NK2 receptor (IC50 = 115 nM) and showed weak partial stimulation of PI turnover (approximately 10-15% of NKA maximum). 6 behaves as a competitive antagonist of NKA-stimulated PI turnover with a pA2 = 6.7. The secondary amine of the psi (CH2NH) moiety of 6 was converted to a tertiary amine by alkylation. This modification was found to have a small effect upon receptor affinity but did result in attenuation of partial agonist activity. A combination of amino acid substitutions and psi (CH2NH) alkylation yielded [beta Ala8,psi (CH2N(CH2)2CH3)9,Phe10]NKA4-10 (21) which has very high affinity for the HUB NK2 receptor. This compound inhibited [125I]NKA binding with an IC50 = 1 nM which is equal to the receptor affinity of NKA. Compound 21 also shows very weak partial agonism of PI turnover (< or = 5% of NKA maximum) which makes this the most potent member of a new class of NKA ligands: psi(CH2NR)9-NKA4-10 analogues which potently antagonize NKA binding and possess minimal partial agonist activity.


Assuntos
Neurocinina A/química , Fragmentos de Peptídeos/química , Receptores de Neurotransmissores/metabolismo , Sequência de Aminoácidos , Animais , Cricetinae , Técnicas In Vitro , Ligantes , Dados de Sequência Molecular , Neurocinina A/metabolismo , Oxirredução , Fragmentos de Peptídeos/metabolismo , Fosfatidilinositóis/metabolismo , Receptores da Neurocinina-2 , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo
6.
Cancer Chemother Pharmacol ; 35(6): 457-63, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7882454

RESUMO

Increasing evidence suggests that P-glycoprotein (Pgp) expression can mediate drug resistance in refractory breast cancer. We studied 33 patients with refractory breast cancer enrolled in a pilot study of oral amiodarone as a Pgp antagonist given in combination with infusional doxorubicin or vinblastine. Whenever possible, tumors were biopsied and Pgp expression was assayed. Patients received either 60 mg/m2 doxorubicin over 96 h or 8.5 mg/m2 vinblastine over 120 h by continuous intravenous infusion. Beginning with the second cycle of chemotherapy, 600-800 mg amiodarone was given orally each day. Patients who experienced toxicity due to amiodarone but were responding to chemotherapy were placed on quinidine. Partial responses were observed in 9 of 33 patients on study and were sometimes observed after the first cycle of chemotherapy, before amiodarone was given, suggesting that some patients may have responded to treatment because of the infusional schedule. Toxicities were primarily the known side effects of the antineoplastic agents and of amiodarone. The major amiodarone toxicity was gastrointestinal, with nausea, vomiting, anorexia, or diarrhea being noted in 21 patients. Biopsy samples were obtained from 29 patients and in 21 cases, viable tumor tissue was present and the results were interpretable. Of the 21 samples, 9 had Pgp expression as determined by immunohistochemical staining; 12 were considered negative. The presence of Pgp expression was associated with an acceleration of the time to treatment failure. Whereas normal-tissue toxicities related to the combination of a Pgp antagonist with chemotherapy were not observed, amiodarone was associated with too many untoward effects to be utilized as a drug resistance-reversing agent.


Assuntos
Amiodarona/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/uso terapêutico , Vimblastina/uso terapêutico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Administração Oral , Adulto , Idoso , Amiodarona/administração & dosagem , Amiodarona/efeitos adversos , Amiodarona/sangue , Biópsia , Neoplasias da Mama/ultraestrutura , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/sangue , Resistência a Medicamentos , Feminino , Humanos , Imuno-Histoquímica , Infusões Intravenosas , Pessoa de Meia-Idade , Projetos Piloto , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos , Vimblastina/sangue
7.
Nucleosides Nucleotides Nucleic Acids ; 20(4-7): 1067-78, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11562960

RESUMO

Cyclin-dependent kinases (CDKs) belong to a class of enzymes that control the ability of a cell to enter into and proceed through the cell division cycle. Using purine as a scaffold, we have synthesized a number of nanomolar inhibitors of CDK-2/cyclin E. In this report, the synthesis of a series of piperidine-substituted purine analogs will be presented, as well as some of their in vitro and in vivo biological effects.


Assuntos
Adenina/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Quinases relacionadas a CDC2 e CDC28 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Piperidinas/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Purinas/síntese química , Purinas/farmacologia , Adenina/análogos & derivados , Adenina/síntese química , Animais , Quinase 2 Dependente de Ciclina , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Piperidinas/síntese química , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Arch Environ Health ; 51(5): 368-74, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8896386

RESUMO

There have been claims of an increased risk for gestational trophoblastic disease (i.e., hydatidiform mole and choriocarcinoma) in Vietnam since the period of Agent Orange sprayings. In 1990, we conducted a case-control study in Ho Chi Minh City to investigate risk factors for gestational trophoblastic disease in Vietnam. Eighty-seven married women, all of whom had a recent pathologic diagnosis of gestational trophoblastic disease, identified in the Obstetrical and Gynecological Hospital, were included in the study. Eighty-seven married women who were admitted mainly in the surgery departments of the same hospital were the controls, and they were matched to cases for age and area of residence. Odds ratios (ORs), adjusted for matching variables and other potential confounders, were estimated with unconditional logistic regression. A statistically significant trend in risk was observed with previous live births (p = .01). Cases were found to eat less meat per wk (OR = 0.4, 95% confidence interval [95% CI] = 0.2-0.9 for > or = five meat dishes) and to own fewer consumer goods than controls. An increase in risk was associated with the breeding of pigs (OR = 5.7, 95% CI = 1.2-27.6 for raising three or more pigs). A cumulative Agent Orange exposure index was constructed, using the patient's complete residence history. No significant difference was found between cases and controls for this index (OR = 0.7, 95% CI = 0.2-1.8 for high-exposure category), nor was such a difference noted for the agricultural use of pesticides.


Assuntos
Ácido 2,4,5-Triclorofenoxiacético/efeitos adversos , Ácido 2,4-Diclorofenoxiacético/efeitos adversos , Desfolhantes Químicos/efeitos adversos , Exposição Materna , Dibenzodioxinas Policloradas/efeitos adversos , Neoplasias Trofoblásticas/induzido quimicamente , Neoplasias Uterinas/induzido quimicamente , Adulto , Agente Laranja , Criação de Animais Domésticos , Animais , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Razão de Chances , Gravidez , Fatores de Risco , Inquéritos e Questionários , Suínos , Vietnã
9.
Hand Clin ; 16(4): 597-607, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11117050

RESUMO

Successful treatments of musculoskeletal injuries in the pediatric population demand a thorough understanding of the basic anatomy and its biomechanics, and the physiology of growth and development of the immature skeleton. In addition, good treatment outcomes rely on the treating physician being an effective teacher to the young athlete and the patient's parents, coaches, and trainers. At the same time, the physician must be a good student in learning the nature of the patient's sports and each patient's athletic ability and aspirations. Most pediatric hand and wrist injuries can be treated nonoperatively with proper immobilization techniques and activity modification, but cases requiring surgical intervention must be recognized promptly to avoid long-term complications.


Assuntos
Traumatismos em Atletas/terapia , Fraturas Ósseas/terapia , Traumatismos da Mão/terapia , Traumatismos do Punho/terapia , Traumatismos em Atletas/diagnóstico , Fraturas Ósseas/diagnóstico , Traumatismos da Mão/diagnóstico , Humanos , Luxações Articulares/diagnóstico , Luxações Articulares/terapia , Osso Escafoide/lesões , Traumatismos do Punho/diagnóstico
11.
Exp Neurol ; 167(1): 126-32, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11161600

RESUMO

Youth is a strong predictor of functional recovery after peripheral nerve repair, while adulthood is commonly associated with poor outcome. Identification of the factors responsible for this difference could form the basis for strategies to improve regeneration in adults. Preferential reinnervation of motor pathways by motor axons (PMR) occurs strongly in young rats, but is often absent in older animals, and thus parallels the overall trend for superior results in young individuals. These experiments evaluate the individual contributions of peripheral nerve age and motoneuron age to the decline in regeneration specificity (PMR) which accompanies the aging process. The femoral nerves of young and old Lewis rats were removed as inverted "Y" grafts from the femoral trunk proximally to the terminal muscle and cutaneous branches distally. These grafts were transferred from (1) old to young, (2) young to old, (3) old to old, and (4) young to young bilaterally in 10 individuals per group. After 8 weeks of regeneration, reinnervation of cutaneous and muscle branches was assessed by dual labeling with HRP and Fluoro-Gold. Motor neuron regeneration was random in old to old (mean muscle branch (M) = 159, mean cutaneous branch (C) = 168), but PMR was seen when young pathways were used in old animals (M = 163, C = 116). PMR was vigorous when either type of graft was used in young animals (young graft, M = 218, C = 134; old graft, M = 204, C = 127). In this model, motoneuron age appears to be the primary determinant of specificity. However, the pathway also makes significant contributions, as shown by the ability of young pathways to generate specificity in old animals. Manipulation of graft Schwann cell behavior might therefore be an appropriate strategy to improve outcome in older individuals.


Assuntos
Envelhecimento/fisiologia , Axônios/fisiologia , Neurônios Motores/fisiologia , Regeneração Nervosa/fisiologia , Vias Neurais/fisiologia , Estilbamidinas , Fatores Etários , Animais , Contagem de Células , Nervo Femoral/fisiologia , Nervo Femoral/transplante , Corantes Fluorescentes , Peroxidase do Rábano Silvestre , Neurônios Motores/citologia , Músculo Esquelético/inervação , Vias Neurais/citologia , Ratos , Ratos Endogâmicos Lew , Sensibilidade e Especificidade , Pele/inervação
12.
Clin Orthop Relat Res ; (373): 141-5, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10810471

RESUMO

Osteonecrosis is a disease that leads to joint destruction and often involves large joints, such as the hips, knees, and shoulders. Nontraumatic osteonecrosis of the adult elbow, to the best of the authors' knowledge, has not been reported. Nine adult patients with atraumatic osteonecrosis of 11 elbows were identified. The mean age at presentation was 36 years (range, 26-63 years); five patients were women and four were men. Six elbows involved the capitellum, three involved the lateral epicondyles, one involved the trochlea and radial head, and one involved medial and lateral epicondylar disease. All patients were receiving corticosteroid therapy, and no relationship between the duration or the amount of corticosteroid use and the severity of the osteonecrosis was found. Seven patients with radiographic Stage I and Stage II disease responded well to nonoperative treatments consisting of activity modification, analgesics, and a brief period of immobilization. Nonoperative treatment failed in two patients with Stage III disease, and they had core decompressions for pain relief. One patient with late Stage III disease in both elbows underwent bilateral total elbow arthroplasties. In contrast to the pediatric population, osteonecrosis of the adult elbow potentially can lead to end stage arthritis. If the osteonecrosis is diagnosed early, nonoperative treatment may be effective in relieving pain, although the long-term results of these treatments remain unknown.


Assuntos
Articulação do Cotovelo , Osteonecrose/cirurgia , Corticosteroides/efeitos adversos , Adulto , Artroplastia , Descompressão Cirúrgica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteonecrose/diagnóstico , Osteonecrose/etiologia , Fatores de Risco , Resultado do Tratamento
13.
Int J Cancer ; 55(2): 196-201, 1993 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-7690345

RESUMO

A case-control study investigating risk factors for hepatocellular carcinoma (HCC) was conducted in Hanoi, in the north of Vietnam, between 1989 and 1992. Male cases of HCC (152) diagnosed in 2 hospitals were included. Hospital controls (241) admitted mainly to abdominal surgery departments were frequency-matched to cases for sex, age, hospital and place of residence (Hanoi, province). Odds ratios adjusted for matching variables and other potential confounders were estimated using unconditional logistic regression, or exact non-parametric statistical inference when numbers were small. Positivity for hepatitis B surface antigen (HBsAg) was the main risk factor for HCC in this sample. Five subjects (3 cases, 2 controls) had been infected by hepatitis C virus (HCV), and none of them were carriers of HBsAg, giving an OR of 38 associated with HCV infection among HBsAG-negative subjects. Alcohol drinking was associated with HCC and interacted with HBsAg positivity. Agricultural use of organophosphorous pesticides (30 liters/year or more) and military service in the south of Vietnam for 10 years or more were also associated with an increased risk of HCC. This study confirms the major role played by HBV infection and its association with HCC in south-east Asia. It also suggests how other factors such as alcohol consumption or exposure to chemicals may interact with HBV infection.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Dioxinas/efeitos adversos , Exposição Ambiental/efeitos adversos , Hepatite B/complicações , Herbicidas/efeitos adversos , Neoplasias Hepáticas/epidemiologia , Ácido 2,4,5-Triclorofenoxiacético/efeitos adversos , Ácido 2,4-Diclorofenoxiacético/efeitos adversos , Adulto , Agente Laranja , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/imunologia , Estudos de Casos e Controles , Exposição Ambiental/estatística & dados numéricos , Anticorpos Anti-Hepatite/sangue , Hepatite B/epidemiologia , Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Hepatite C/complicações , Hepatite C/epidemiologia , Hepatite C/imunologia , Anticorpos Anti-Hepatite C , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/imunologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/estatística & dados numéricos , Praguicidas/efeitos adversos , Dibenzodioxinas Policloradas/efeitos adversos , Fatores de Risco , Vietnã/epidemiologia
14.
Asia Pac J Clin Nutr ; 8(1): 36-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24393734

RESUMO

The iron and vitamin C content of water spinach and rice samples from three sites in Vietnam were chemically analysed. The iron content of home-milled rice from Nghe An was higher than the iron content of machine-milled rice from Thai Binh and Hanoi. In addition, the iron content of cooked rice was lower than that of uncooked rice as iron was removed during the washing and rinsing of the rice prior to cooking. Cooked rice that was washed and rinsed less thoroughly had a higher iron content. The iron content of water spinach from different locations was very similar, although white water spinach had a much higher vitamin C content than red water spinach.

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