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1.
Ultrasound Obstet Gynecol ; 53(3): 383-389, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29947159

RESUMO

OBJECTIVE: To examine the efficacy of biweekly hyperimmunoglobulin (HIG) administration to prevent maternal-fetal transmission of cytomegalovirus (CMV) in women with primary first-trimester CMV infection. METHODS: This was a prospective observational study of women with confirmed primary CMV infection in the first trimester who had the first HIG administration at or before 14 weeks' gestation. All women had biweekly HIG treatment until 20 weeks' gestation at a dose of 200 IU/kg of maternal body weight. Each subject underwent amniocentesis at least 6 weeks after first presentation at about 20 weeks. Primary outcome was maternal-fetal transmission at the time of amniocentesis, and secondary outcome was the frequency of congenital CMV infection at birth. The results were compared with a historic cohort of women with first-trimester CMV infection who did not undergo HIG treatment and who had amniocentesis at about 20 weeks. RESULTS: Subjects were 40 pregnant women with a primary CMV infection, with a median gestational age at first presentation of 9.6 (range, 5.1-14.3) weeks. On average, HIG administration started at 11.1 weeks and continued until 16.6 weeks. Within this interval, HIG was administered between two and six times in each patient. While CMV immunoglobulin-G (IgG) monitoring showed periodic fluctuations during biweekly HIG administration cycles, high CMV-IgG avidity indices remained stable over the whole treatment period. Maternal-fetal transmission before amniocentesis occurred in only one of the 40 cases (2.5% (95% CI, 0-13.2%)). At delivery, two additional subjects were found to have had late-gestation transmission. Considering all three cases with maternal-fetal transmission, the transmission rate was 7.5% (95% CI, 1.6-20.4%) in our 40 cases. All infected neonates were asymptomatic at birth. The matched historical control group consisted of 108 pregnancies. Thirty-eight transmissions (35.2% (95% CI, 26.2-45.0%)) occurred in the control group, which was significantly higher (P < 0.0001) than the transmission rate in the HIG treatment group. CONCLUSION: After a primary maternal CMV infection in the first trimester, biweekly HIG administration at a dose of 200 IU/kg prevents maternal-fetal transmission up to 20 weeks' gestation. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Infecções por Citomegalovirus/prevenção & controle , Citomegalovirus/isolamento & purificação , Doenças Fetais/prevenção & controle , Imunoglobulinas/administração & dosagem , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Adulto , Amniocentese/métodos , Feminino , Doenças Fetais/virologia , Idade Gestacional , Humanos , Imunoglobulina G/análise , Imunoglobulinas/uso terapêutico , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Primeiro Trimestre da Gravidez/sangue , Estudos Prospectivos , Resultado do Tratamento
2.
Neuroimage ; 167: 247-255, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27321046

RESUMO

Functional imaging studies on mental rotation of hands have consistently pointed to the importance of the motor network implying the use of motor simulations for task solving. There is some evidence that the putamen may be a critical modulator of processing egocentric spatial orientation in mental rotation of hands and implicit motor imagery strategies have been described involving hand motor areas. This recruitment of resources processing representations of the own body is used in therapeutic mental rotation training. However, studies are lacking that investigate training-induced changes on the neuronal level. We used functional MRI to study the effects of long-term training on the neuro-functional correlates of mental rotation of hands in healthy volunteers and compared the training group to a passive control group. From pre- to post training, we found a transition of activation from the anterior putamen in unskilled performance to the posterior putamen in skilled performance. We also found an increase in activation in motor cortices and the supramarginal gyrus after learning. By contrast, members of the control group showed no improvements in performance and no pre/post-test differences in cortical activity. In conclusion, these findings suggest that increased neural efficiency after training in mental rotation of hands manifests as a decrease in visual imagery in conjunction with increased recruitment of motor-related regions. This is consistent with the obtained behavioral effects depicting motor imagery mediating expertise in mental rotation of hands.


Assuntos
Mãos/fisiologia , Imaginação/fisiologia , Aprendizagem/fisiologia , Atividade Motora/fisiologia , Córtex Motor/fisiologia , Lobo Parietal/fisiologia , Putamen/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Putamen/diagnóstico por imagem , Adulto Jovem
3.
Neuroimage ; 64: 379-87, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22982586

RESUMO

Long-term intensive sensorimotor training alters functional representation of the motor and sensory system and might even result in structural changes. However, there is not much knowledge about how previous training impacts learning transfer and functional representation. We tested 14 amateur pianists and 15 musically naïve participants in a short-term finger sequence training procedure, differing considerably from piano playing and measured associated functional representation with functional magnetic resonance imaging. The conditions consisted of encoding a finger sequence indicated by hand symbols ("sequence encoding") and subsequently replaying the sequence from memory, both with and without auditory feedback ("sequence retrieval"). Piano players activated motor areas and the mirror neuron system more strongly than musically naïve participants during encoding. When retrieving the sequence, musically naïve participants showed higher activation in similar brain areas. Thus, retrieval activations of naïve participants were comparable to encoding activations of piano players, who during retrieval performed the sequences more accurately despite lower motor activations. Interestingly, both groups showed primary auditory activation even during sequence retrieval without auditory feedback, supporting previous reports about coactivation of the auditory cortex after learned association with motor performance. When playing with auditory feedback, only pianists lateralized to the left auditory cortex. During encoding activation in left primary somatosensory cortex in the height of the finger representations had a predictive value for increased motor performance later on (error rates). Contrarily, decreased performance was associated with increased visual cortex activation during encoding. Our study extends previous reports about training transfer of motor knowledge resulting in superior training effects in musicians. Performance increase went along with activity in motor areas and the mirror neuron network during pattern encoding.


Assuntos
Dedos/fisiologia , Memória de Curto Prazo/fisiologia , Córtex Motor/fisiologia , Destreza Motora/fisiologia , Movimento/fisiologia , Música , Aprendizagem Seriada/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Análise e Desempenho de Tarefas
4.
Infection ; 41(4): 875-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23546999

RESUMO

In solid organ transplantation, human cytomegalovirus (HCMV) is considered to be the most important viral pathogen. We report a case of a CMV R-/D+ small intestine transplant recipient with a primary CMV infection on valganciclovir prophylaxis. Sequencing of the HCMV DNA for drug resistance-associated mutations revealed the UL97 mutation N510S. This mutation has been initially reported to confer ganciclovir resistance. Based on in vitro recombinant phenotyping, this assumption has recently been questioned. Switching the antiviral treatment to an intravenous regimen of ganciclovir eliminated HCMV DNAemia, showing the in vivo efficacy of ganciclovir for the UL97 mutation N510S. Hence, knowledge of drug efficacy is crucial for an adequate choice of antiviral medication, carefully balancing antiviral potency versus the risk of harmful side effects.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Citomegalovirus/efeitos dos fármacos , Farmacorresistência Viral , Ganciclovir/uso terapêutico , Hospedeiro Imunocomprometido , Transplante , Antivirais/farmacologia , Quimioprevenção/métodos , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/diagnóstico , DNA Viral/genética , Ganciclovir/análogos & derivados , Ganciclovir/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/tratamento farmacológico , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Análise de Sequência de DNA , Resultado do Tratamento , Valganciclovir
5.
Epidemiol Infect ; 140(5): 835-41, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21781370

RESUMO

Human cytomegalovirus (CMV) is a common herpesvirus establishing lifelong persisting infection, which has been implicated in immunosenescence and mortality in the elderly. Little is known about how and when susceptibility to CMV infection is determined. We measured CMV seroprevalence in two genetically informative cohorts. From the Leiden Longevity Study (LLS) we selected long-lived sib-pairs (n=844) and their middle-aged offspring and the offspring's partners (n=1452). From the Longitudinal Study of Aging Danish Twins (LSADT) 604 (302 pairs) same-sex monozygotic (MZ) and dizygotic (DZ) twins aged 73-94 years were included (n=302 pairs). Offspring of the long-lived LLS participants had significantly lower seroprevalence of CMV compared to their partners (offspring: 42% vs. partners: 51%, P=0·003). Of 372 offspring living with a CMV-positive partner, only 58% were infected. The corresponding number for partners was 71% (P<0·001). In the LSADT, MZ and DZ twins had high and similar CMV-positive concordance rates (MZ: 90% vs. DZ: 88%, P=0·51) suggesting that shared family environment accounts for the similarity within twin pairs. Our findings suggest that susceptibility to CMV infection--even under continuous within-partnership exposure--appears to be more strongly influenced by early-life environment than by genetic factors and adult environment.


Assuntos
Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/epidemiologia , Longevidade , Idoso , Idoso de 80 Anos ou mais , Dinamarca/epidemiologia , Suscetibilidade a Doenças , Feminino , Humanos , Estudos Longitudinais , Masculino , Países Baixos/epidemiologia , Estudos Soroepidemiológicos , Análise de Sobrevida , Gêmeos
6.
Gen Comp Endocrinol ; 166(3): 556-64, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20152839

RESUMO

The severe environments where Phymaturus lizards inhabit in the Andes highlands and in Patagonia, Argentina, impose restrictions on their reproduction, offering a framework for the development of life history strategies to overcome hard weather conditions. Among them, prolonged female cycles, asynchrony between sexes in receptivity, and sperm storage in males, were described. Asynchrony in the reproductive timing between males and females is a consequence of different energy requirements for gametogenesis, and often imply the existence of cellular mechanisms to enhance fertilization, such as the asynchronic steroid synthesis between testicular compartments, allowing gametogenesis independently of mating. In the present study ultrastructural and hormone assays were combined for the first time in liolaemids. Specifically, morphological features of steroid activity in Leydig and Sertoli cells, and serum testosterone concentrations have been studied in the lizard Phymaturus antofagastensis. Leydig and Sertoli cells presented morphological features characteristic of steroid synthesis during the spermatogenesis, and evident asynchronic steroid production between testicular compartments. Active Sertoli cells and inactive Leydig cells were observed in spring and autumn, while in mid-summer their steroid activity was synchronic in coincidence with maximal abundance of spermatozoa in epididymis. Serum testosterone concentration was at its maximum in mid-summer (126-230 ng ml(-1)), and minimum in late spring (4-24 ng ml(-1)) and early autumn (2-17 ng ml(-1)). In view of these results, P. antofagastensis males show an original approach to adjust their reproductive activity to physiological and environmental constraints at high latitudes and altitudes in the Andean highlands of Argentina.


Assuntos
Células Intersticiais do Testículo/ultraestrutura , Lagartos/metabolismo , Lagartos/fisiologia , Células de Sertoli/ultraestrutura , Espermatogênese/fisiologia , Testosterona/sangue , Animais , Masculino , Microscopia Eletrônica de Transmissão
7.
Curr Top Microbiol Immunol ; 325: 63-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18637500

RESUMO

The human cytomegalovirus (HCMV) can infect a remarkably broad cell range within its host, including parenchymal cells and connective tissue cells of virtually any organ and various hematopoietic cell types. Epithelial cells, endothelial cells, fibroblasts and smooth muscle cells are the predominant targets for virus replication. The pathogenesis of acute HCMV infections is greatly influenced by this broad target cell range. Infection of epithelial cells presumably contributes to inter-host transmission. Infection of endothelial cells and hematopoietic cells facilitates systemic spread within the host. Infection of ubiquitous cell types such as fibroblasts and smooth muscle cells provides the platform for efficient proliferation of the virus. The tropism for endothelial cells, macrophages and dendritic cells varies greatly among different HCMV strains, mostly dependent on alterations within the UL128-131 gene locus. In line with the classification of the respective proteins as structural components of the viral envelope, interstrain differences concerning the infectivity in endothelial cells and macrophages are regulated on the level of viral entry.


Assuntos
Citomegalovirus/fisiologia , Receptores Virais , Internalização do Vírus , Humanos
8.
Mol Cell Endocrinol ; 490: 88-99, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004687

RESUMO

To characterize the influence of hypothyroidism on the endocrine activity of mesenteric and omental adipose tissue (MOAT) and the peripheral regulation of energy balance (EB) in rats, we analyzed food intake (FI); basal metabolic rate (BMR); locomotor activity; body weight (BW); serum hormone concentrations and the expression of their receptors in MOAT. We evaluated the morphology and differentiation of adipocytes. Hypothyroidism decreased FI, BMR and BW. The percentage of visceral white adipose tissue (WAT) depots and the morphology of adipocytes were similar to euthyroid rats. Serum leptin and adiponectin expression in MOAT were altered by hypothyroidism. The expression of Perilipin 1, HSL, UCP1 and PRDM16 was significantly lower in MOAT of hypothyroid animals. Hypothyroidism in rats leads to a compensated EB by inducing a white adipocyte dysfunction and a decrease in BW, BMR, FI and adipokine secretions without changing the percentage of WAT depots and the morphology of the MOAT.


Assuntos
Tecido Adiposo/patologia , Hipotireoidismo/patologia , Mesentério/patologia , Omento/patologia , Adipócitos/metabolismo , Adipocinas/sangue , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Metabolismo Basal , Biomarcadores/metabolismo , Peso Corporal , Corticosterona/metabolismo , Ingestão de Alimentos , Ácidos Graxos/metabolismo , Feminino , Glucose/metabolismo , Hipotireoidismo/sangue , Insulina/metabolismo , Atividade Motora , Ovário/metabolismo , Propiltiouracila/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
9.
J Perinatol ; 28(1): 79-81, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18165834

RESUMO

Norovirus is increasingly recognized as a frequent cause of non-bacterial gastroenteritis. Despite a 10-fold increase in the number of cases reported following the availability of enzyme immunoassays, there are no reports yet from preterm neonates. We report on a sudden clustering of antigen-positive enzyme immuno assays results in a level III neonatal intensive care unit, involving 22 of 43 infants screened. Although antigen-positive samples were significantly associated with bloody stools (P<0.001) and gastric residues (P<0.02), norovirus infection could not be confirmed by reverse-transcriptase polymerase chain reaction or electron microscopy. We question the validity of the so called norovirus-specific antigen assays and warn against overreacting to positive enzyme immunoassays results without reverse-transcriptase polymerase chain reaction confirmation especially in the neonatal setting.


Assuntos
Infecções por Caliciviridae/diagnóstico , Ensaio de Imunoadsorção Enzimática/normas , Fezes/virologia , Gastroenterite/virologia , Norovirus/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/métodos , Reações Falso-Positivas , Alemanha , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Terapia Intensiva Neonatal , Kit de Reagentes para Diagnóstico/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Arch Dis Child Fetal Neonatal Ed ; 91(4): F288-90, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16790732

RESUMO

Freezing human milk is recommended to inactivate cytomegalovirus (CMV). A case of a preterm infant exclusively receiving frozen breast milk from his CMV seropositive mother showed that storage of breast milk for two months at -20 degrees C did not prevent symptomatic postnatal CMV infection.


Assuntos
Criopreservação , Infecções por Citomegalovirus/transmissão , Recém-Nascido Prematuro , Leite Humano/virologia , Infecções por Citomegalovirus/prevenção & controle , Evolução Fatal , Seguimentos , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Masculino
11.
Clin Microbiol Infect ; 22(2): 209.e5-209.e8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26482270

RESUMO

To evaluate the human herpes virus 6 (HHV-6) -specific immune response in individuals with chromosomally integrated HHV-6 (ciHHV-6), we measured HHV-6-antigen-specific cytokine responses (interferon-γ, interleukin-2, tumour necrosis factor-α) in T cells by flow cytometry in 12 and 16 individuals with and without ciHHV-6, respectively. All individuals with ciHHV-6 showed HHV-6-specific T cells with higher frequencies of HHV-6-specific CD8(+) cells (0.03-14.93, median 2.15% of CD8(+) cells) compared with non-ciHHV-6 (0.0-10.67, median 0.36%, p 0.026). The observed increased HHV-6-specific functionally active responses in individuals with ciHHV-6 clearly disprove speculations on immune tolerance in ciHHV-6 and indicate clinical and immunological implications of ciHHV-6.


Assuntos
Citocinas/metabolismo , Herpesvirus Humano 6/genética , Infecções por Roseolovirus/virologia , Linfócitos T/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Roseolovirus/genética , Infecções por Roseolovirus/imunologia , Linfócitos T/metabolismo , Integração Viral , Adulto Jovem
12.
Viral Immunol ; 18(3): 534-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16212532

RESUMO

To monitor the frequencies of virus-specific cytotoxic T lymphocytes (CTLs), FACS analyses were performed detecting lymphocyte-specific surface molecules and tetramer binding, as marker for peptide-specificity. Aim of this investigation was to establish an alternative protocol for the quantification of virus-specific CTLs using tetramer binding and microscopic analyzing. The frequencies of HCMV-pp65-peptide-specific CTLs in the blood of eight different HLA-A*0201-positive, HCMV-IgG antibody-positive donors were analyzed with both methods. Using FACS analyses, a median of 0.8% and, using the microscopic analyses, a median of 3.0% was detected in the CD3+CD8+ cells. After enrichment of HCMV-pp65-peptide-specific CTLs using the interferon-gamma secretion assay followed by expansion in cell culture, a median of 90.6% using FACS analyses and a median of 87.1% using the microscopic analyses was detected. Thus, the staining protocol presented in this investigation is an alternative approach to detect and to quantify virus-specific CTLs in low as well as in high frequencies.


Assuntos
Citomegalovirus/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Separação Celular , Citomegalovirus/genética , Citometria de Fluxo , Antígenos HLA-A , Antígeno HLA-A2 , Humanos , Técnicas Imunológicas , Técnicas In Vitro , Microscopia de Fluorescência , Oligopeptídeos/genética , Oligopeptídeos/imunologia , Fosfoproteínas/genética , Fosfoproteínas/imunologia , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/imunologia
13.
Endocrinology ; 128(6): 2976-84, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2036972

RESUMO

The expression of two forms of PRL receptor messenger RNA was measured at different stages of pregnancy and lactation in mammary gland and liver from Sprague-Dawley rats, using 32P-labeled complementary DNA probes encoding the extracellular part of the receptor (E probe), common to the two forms and a probe encoding the intracellular part of the long form of the receptor (I probe), that only recognizes sequences specific to the long form of the receptor. Hybridizations were performed in Northern blots obtained from electrophoreses of poly (A+) enriched RNA preparations from mammary glands and livers of rats on days 0, 6, 12, 19, and 21 of pregnancy and 5, 10, 15, and 20 of lactation. The Northern blots were also hybridized with a chicken beta-actin probe, to correct for the amount of mRNA added and the different metabolic states of the tissues. Both tissues expressed the same forms of PRL receptor mRNAs, namely bands at 2.5, 3, and 5.5 kilobases encoding the long form of the receptor and a major band at 1.8 kilobases encoding the short form. The liver expressed all the receptor mRNA forms in much higher quantity than the mammary gland, independent of the reproductive state. In liver there was an increase of all the transcripts on day 19 of pregnancy, followed by an abrupt decline at the onset of lactation, to levels lower than those of virgin rats. In contrast, mammary gland PRL receptor mRNAs were low in virgin and pregnant animals, increased significantly at day 21 of pregnancy, and continued to increase throughout lactation. Treatment of day 19 pregnant rats with the antiprogesterone RU 486 induced, 24 h later, PRL receptor mRNAs in mammary gland but not in liver. There were no significant differences in the relative proportions of long to short forms of PRL receptor mRNAs at the different reproductive states, but the proportion of the long form was slightly greater in mammary gland than in liver. Membrane PRL receptor concentrations were also measured in the same tissues used for the mRNA study by binding to a 125I-labeled monoclonal antibody (U5), which specifically recognizes the PRL receptor at a site different from the hormone binding site. The quantity of receptor measured by U5 binding was approximately 3 times higher than that measured with 125I-labeled ovine PRL.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Regulação da Expressão Gênica , Lactação/fisiologia , Fígado/fisiologia , Glândulas Mamárias Animais/fisiologia , Prenhez/fisiologia , Receptores da Prolactina/genética , Animais , Feminino , Fígado/metabolismo , Masculino , Glândulas Mamárias Animais/metabolismo , Mifepristona/farmacologia , Concentração Osmolar , Gravidez , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos
14.
Clin Infect Dis ; 33(12): 1998-2003, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11712092

RESUMO

In addition to seroprevalence and transmission rate, the clinical symptoms of postnatal cytomegalovirus (CMV) infection in infants with a very low birth weight (VLBW; <1500 g; <32 weeks gestational age at birth) were assessed in a 3-year prospective study. CMV monitoring included serologic testing (of the mother and child) and virus culture and PCR (of samples of both breast milk and the infant's urine). Within 3 weeks of the initial virus detection in the infant, clinical and laboratory parameters were evaluated. Of 170 infants, no CMV transmission was found in the 80 infants of seronegative mothers and in the 3 infants of seropositive mothers who did not shed CMV DNA into breast milk. Transmission occurred in 33 of the 87 CMV-exposed infants, 16 of whom presented with such symptoms as hepatopathy, neutropenia, thrombocytopenia, and sepsis-like deterioration. Low birth weight and early postnatal virus transmission were risk factors for symptomatic infection. VLBW infants of CMV-seropositive mothers are at high risk of acquiring a symptomatic CMV infection postnatally via breast milk.


Assuntos
Infecções por Citomegalovirus/epidemiologia , Recém-Nascido de muito Baixo Peso , Leite Humano/virologia , Infecções por Citomegalovirus/transmissão , DNA Viral/análise , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Hepatopatias/virologia , Masculino
15.
Gene ; 130(2): 167-73, 1993 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-8395449

RESUMO

Studies on the biology and function of human cytomegalovirus (HCMV) genes have been hampered by the limited number of viral mutants available for genetic analyses. We have developed a simple procedure to generate and enrich for HCMV recombinants. By inserting the bacterial neo gene, encoding neomycin/kanamycin phosphotransferase, into the large HCMV DNA genome using homologous recombination, selectable mutants of this complex herpesvirus were isolated for the first time. The synthesis of Neo from the viral genome was used to effectively enrich for recombinant viruses (re-viruses) in permissive culture cells grown in the presence of Geneticin (G418). A quick assay for Neo activity in infected cells, based on phosphorylation of kanamycin (Km), was used to easily identify viral recombinants in the process of screening and isolation. This procedure, not used previously to identify re-viruses, proved to be very useful for screening of large numbers of HCMV recombinants. Analysis of re-virus by Southern blotting revealed that the insertion of the marker gene had resulted in the expected deletion of the open reading frames, TRL 13/14 and UL 1-5, of HCMV. Re-virus was stable and showed no differences in growth kinetics as compared to wild-type (wt) virus. The insertion of a selectable marker gene into the HCMV genome and identification of viral recombinants by the Km phosphorylation assay, as presented here, provides the rationale for effective generation, enrichment and stable propagation of HCMV mutants.


Assuntos
Citomegalovirus/genética , Mutagênese Sítio-Dirigida , Fosfotransferases/genética , Southern Blotting , Células Cultivadas , Citomegalovirus/isolamento & purificação , DNA Viral , Genes Bacterianos , Humanos , Canamicina/metabolismo , Canamicina Quinase , Fenótipo , Fosforilação , Recombinação Genética
16.
Gene ; 129(2): 263-8, 1993 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-7686871

RESUMO

We report the construction of a high-copy-number (hcn) expression vector for human cells. Amplification of this vector occurs due to the presence of an element derived from the murine DNA encoding ribosomal RNA (rDNA). HIV-1 replication in Jurkat T lymphocytes is nearly abolished when antisense RNA directed against the gene encoding reverse transcriptase is expressed from this hcn vector. The replication of the virus is only slightly reduced by the plasmid control version lacking the murine amplification-promoting element. This kind of hcn vector may represent an important improvement for the genetic engineering of eukaryotic cells and may also provide some ideas for the future gene therapy of some human diseases.


Assuntos
Amplificação de Genes , Vetores Genéticos , HIV-1/fisiologia , RNA Antissenso/fisiologia , Replicação Viral/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Engenharia Genética , Transcriptase Reversa do HIV , Humanos , Regiões Promotoras Genéticas , Inibidores da Transcriptase Reversa , Linfócitos T , Transfecção/métodos , Células Tumorais Cultivadas
17.
Virus Res ; 12(2): 159-68, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2539706

RESUMO

Recent clinical isolates of human cytomegalovirus (HCMV) display considerable quantitative differences in the expression of the structural phosphoprotein pp65. This study shows that a reduced production of pp65 correlates with reduced amounts of its coding transcript in wild-type strains compared to the high level expression in the laboratory strain AD169. The cleavage pattern of the encoding DNAs including the promoter region did not show major differences among the isolates. Therefore the variable expression of pp65 is supposed to be dependent on cell culture conditions. Increasing multiplicities of infection resulted in overproduction of pp65 and this may lead to the increased formation of dense body particles.


Assuntos
Citomegalovirus/genética , Regulação da Expressão Gênica , Fosfoproteínas/genética , Proteínas Virais/genética , Northern Blotting , Southern Blotting , Western Blotting , Células Cultivadas , Efeito Citopatogênico Viral , DNA Viral/análise , DNA Viral/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Fibroblastos , Humanos , Fosfoproteínas/biossíntese , Regiões Promotoras Genéticas , RNA Viral/análise , RNA Viral/isolamento & purificação , Transcrição Gênica , Proteínas Virais/biossíntese
18.
Virus Res ; 19(2-3): 153-61, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1909827

RESUMO

Peripheral blood mononuclear cells (PBMCs) from 29 patients infected with human immunodeficiency virus (HIV) were cultured by two different methods. One was the standard co-culture technique, the other a newly developed microculture method. In this assay 10(6) PBMCs were cultivated in 250 microliters medium, no activating agents or allogeneic cells were present. P24 antigen production measured by this method was found in 7 out of 11 PBMC cultures of patients in the Walter Reed (WR) stage 1 or 2, whereas only 4 samples were positive by the co-culture procedure. Cultures from patients in the later stages of the disease (WR 5/6) showed a higher p24 production by the co-culture method than by the microculture assay. It is assumed that rapidly growing HIV strains can be better assessed by the co-culture method which may select for these strains. P24 expression can be more easily obtained by the microculture technique even in cases where slowly replicating strains may be present. In conclusion, results from the microculture procedure described may be a useful supplementation to findings observed by the co-culture method.


Assuntos
HIV-1/fisiologia , Leucócitos Mononucleares/microbiologia , Cultura de Vírus/métodos , Adulto , Feminino , Produtos do Gene gag/biossíntese , Antígenos HIV/biossíntese , Proteína do Núcleo p24 do HIV , Infecções por HIV/microbiologia , HIV-1/imunologia , Humanos , Masculino , Proteínas do Core Viral/biossíntese , Replicação Viral
19.
Virus Res ; 24(3): 265-76, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1329369

RESUMO

Monoclonal antibody CCH2 is commonly used for the detection of human cytomegalovirus (HCMV) infected cells in tissue sections as well as in cultured cells. The specificity of CCH2 was determined by screening a recombinant lambda-gt11 cDNA gene bank from HCMV-infected fibroblasts. By sequencing a reactive clone, the antigen was identified to be the non-structural DNA binding protein p52 of HCMV (UL44 reading frame). The viral insert from the lambda clone was recloned in bacterial expression vectors. For this, a new vector, pRos-RS, was constructed. The resulting clones were tested in immunoblot analyses. They were reactive with CCH2 as well as with reconvalescent sera positive for antibodies against HCMV, by this proving the specificity of CCH2. Using this monoclonal antibody in confocal microscopy, the subcellular localization of p52 in infected cells was analyzed. In these analyses, p52 was found to be nuclear and to be associated with the nuclear membrane at late times after infection.


Assuntos
Antígenos Virais/química , Citomegalovirus/química , Proteínas de Ligação a DNA/química , Proteínas Virais/química , Sequência de Aminoácidos , Anticorpos Monoclonais/imunologia , Antígenos Virais/metabolismo , Sequência de Bases , Citomegalovirus/imunologia , Infecções por Citomegalovirus/microbiologia , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Humanos , Microscopia , Dados de Sequência Molecular , Membrana Nuclear/microbiologia , Fatores de Tempo , Proteínas Virais/imunologia , Proteínas Virais/metabolismo
20.
Virus Res ; 29(3): 267-79, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8237111

RESUMO

In 1991 a new HIV-2 isolate (HIV-2HOM) was isolated first from a German individual most likely infected in West Africa in the beginning of the 1970s. The virus was isolated from both, the plasma and the peripheral blood lymphocytes of the patient by using OKT-3-stimulated cord blood lymphocytes. The recovered viruses could be further propagated on Jurkat cells and exhibited a broad cell tropism. Biochemical and antigenic properties of HIV-2HOM were examined by radioimmunoprecipitations. For a more detailed molecular characterization, a 1520 bp DNA fragment from the env gene and a 722 bp DNA fragment from the pol gene were amplified by polymerase chain reactions, cloned and sequenced. A comparison of both sequences to prototypic HIV-2 and SIV isolates revealed a close relationship to HIV-2ST. This strain originated from an asymptomatic Senegalese individual and is supposed to be of reduced pathogenicity. Taking into account genetic data, it may be assumed that HIV-2HOM and HIV-2ST are closely related strains with different growth characteristics and pathogenic features.


Assuntos
DNA Viral/genética , Genes env/genética , Genes pol/genética , Anticorpos Anti-HIV/sangue , Infecções por HIV/microbiologia , HIV-2/isolamento & purificação , Proteínas Virais/química , Sequência de Bases , Produtos do Gene gag/análise , Ligação Genética , Infecções por HIV/sangue , Infecções por HIV/imunologia , HIV-2/química , HIV-2/genética , Homossexualidade , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie
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