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1.
Ultrasound Obstet Gynecol ; 63(2): 251-257, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37610831

RESUMO

OBJECTIVES: To evaluate the relationship between the attitude of the fetal head quantified by means of the chin-to-chest angle (CCA) in fetuses in occiput posterior (OP) position at the beginning of the second stage of labor, and persistent OP position at birth. METHODS: This was a single-center, prospective observational study conducted at the University Hospital of Parma, Parma, Italy. We included singleton pregnancies at term with fetuses in the OP position at the beginning of the second stage of labor. The fetal head position, station by means of angle of progression and head-to-perineum distance, and attitude by means of CCA were assessed using transabdominal or transperineal ultrasound. The primary outcome was persistent OP position at birth. RESULTS: Between January and July 2022, 76 women were included in the study. There were 48 (63.2%) spontaneous rotations of the fetal head and spontaneous vaginal delivery occurred in all. Among the 28 (36.8%) fetuses that did not rotate spontaneously into an occiput anterior position, eight (28.6%) had a spontaneous vaginal delivery, while operative vaginal delivery and Cesarean delivery was performed in 11 (39.3%) and nine (32.1%) cases, respectively. Multivariable logistic regression analysis showed that the CCA (adjusted odds ratio (aOR), 2.15 (95% CI, 1.22-3.78); P = 0.008) and nulliparity (aOR, 0.20 (95% CI, 0.06-0.76); P = 0.02) were associated independently with persistent OP position at birth. Moreover, the CCA showed an area under the receiver-operating-characteristics curve of 0.69 (95% CI, 0.56-0.82); P = 0.005) for the prediction of persistent OP position. The optimal cut-off value of the CCA was 36.5°, and was associated with a sensitivity of 0.82 (95% CI, 0.63-0.94), specificity of 0.50 (95% CI, 0.35-0.65), positive predictive value of 0.49 (95% CI, 0.34-0.64), negative predictive value of 0.83 (95% CI, 0.64-0.94), positive likelihood ratio of 1.64 (95% CI, 1.18-2.29) and negative likelihood ratio of 0.36 (95% CI, 0.15-0.83). CONCLUSIONS: Our data show that, within a population of women with fetal OP position at the beginning of the second stage of labor, the sonographic fetal head attitude measured by means of the CCA might help in the identification of fetuses at risk of persistent OP position. Such findings can be useful for patient counseling when OP position is diagnosed at full cervical dilatation. Further studies should investigate if the CCA might select patients who may benefit from manual rotation of the fetal head. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Feto , Apresentação no Trabalho de Parto , Recém-Nascido , Gravidez , Feminino , Humanos , Estudos Prospectivos , Feto/diagnóstico por imagem , Segunda Fase do Trabalho de Parto , Ultrassonografia Pré-Natal , Parto Obstétrico , Cabeça/diagnóstico por imagem
2.
Opt Express ; 30(26): 46710-46721, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558616

RESUMO

In this work we theoretically investigate quantum confined Stark effect of intersubband transitions in asymmetric Ge/SiGe quantum wells for intensity modulation in the mid-infrared. Our calculations show that extinction ratios up to 1 dB and modulation speeds of several tens of GHz could be obtained in 100 µm long waveguides.

3.
J Endocrinol Invest ; 44(12): 2741-2748, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34173961

RESUMO

INTRODUCTION: Obstructive sleep apnoea (OSA) is an underdiagnosed condition frequently associated with glycaemic control impairment in patients with type 2 diabetes. AIM: To assess the relationship between glycometabolic parameters and OSA in obese non-diabetic subjects. METHODS: Ninety consecutive subjects (mean age 44.9 ± 12 years, mean BMI 42.1 ± 9 kg/m2) underwent polysomnography and a 2-h oral glucose tolerance test (OGTT). RESULTS: OSA was identified in 75% of subjects, with a higher prevalence of males compared to the group of subjects without OSA (62% vs 32%, p = 0.02). Patients with OSA had comparable BMI (42.8 kg/m2 vs 39.4 kg/m2), a higher average HbA1c (5.8% vs 5.4%, p < 0.001), plasma glucose at 120 min during OGTT (2 h-PG; 123 mg/dl vs 97 mg/dl, p = 0.009) and diastolic blood pressure (81.1 mmHg vs 76.2 mmHg, p = 0.046) than obese subjects without OSA. HbA1c and 2 h-PG were found to be correlated with the apnoea-hypopnoea index (AHI; r = 0.35 and r = 0.42, respectively) and with percent of sleep time with oxyhaemoglobin saturation < 90% (ST90; r = 0.44 and r = 0.39, respectively). Further, in a linear regression model, ST90 and AHI were found to be the main determinants of 2 h-PG (ß = 0.81, p < 0.01 and ß = 0.75, p = 0.02, respectively) after controlling for age, sex, waist circumference, physical activity, and C-reactive protein. Similarly, ST90 and AHI persisted as independent determinants of HbA1c (ß = 0.01, p = 0.01 and ß = 0.01, p = 0.01, respectively). CONCLUSION: Beyond the traditional clinical parameters, the presence of a normal-high value of 2 h-PG and HbA1c should raise suspicion of the presence of OSA in obese subjects.


Assuntos
Glicemia/metabolismo , Hemoglobinas Glicadas/análise , Hiperglicemia , Obesidade , Apneia Obstrutiva do Sono , Adulto , Índice de Massa Corporal , Feminino , Teste de Tolerância a Glucose/métodos , Humanos , Hiperglicemia/diagnóstico , Hiperglicemia/epidemiologia , Hiperglicemia/etiologia , Masculino , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Polissonografia/métodos , Período Pós-Prandial , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/sangue , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/fisiopatologia
4.
Ig Sanita Pubbl ; 80(6): 676-692, 2021.
Artigo em Italiano | MEDLINE | ID: mdl-35119055

RESUMO

While the world's economies avoid the COVID-19 pandemic blockade, there is an urgent need for technologies aimed at reducing the transmission of COVID-19 in confined spaces such as hospital environments. Although the cleaning and disinfection procedures now have rather complex and sophisticated weapons, they do not seem to be sufficient to continuously maintain low levels of environmental microbiological contamination. This result can now be achieved through the cross-use, in space and time, of improved, more efficient and effective technologies. This result can now be achieved through the cross-use, in space and time, of improved technologies. This work highlights the possibility of crossing and cooperation of different disinfection techniques, such as to keep the microbial and viral load low over time.


Assuntos
COVID-19 , Infecção Hospitalar , Infecção Hospitalar/prevenção & controle , Desinfecção , Hospitais , Humanos , Pandemias , SARS-CoV-2
5.
Ophthalmologe ; 116(2): 172-175, 2019 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-29767349

RESUMO

This report is on five patients (four men and one woman) between the age of 24 and 66 years old who presented with unclear visual impairment in our clinic between 2009 and 2016 for co-evaluation. The clinical picture included intermediate uveitis, chorioretinitis, panuveitis and bilateral spontaneous cystoid macular edema. None of the patients reported systemic or dermatological symptoms. In all five patients, serological testing revealed a Treponema pallidum infection as the reason for ocular inflammation. The ophthalmologist was therefore the first to discover a syphilitic infection. After initiation of appropriate antibiotic therapy, there was improvement in all five patients and an increase in visual acuity.


Assuntos
Coriorretinite , Edema Macular , Sífilis , Treponema pallidum , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acuidade Visual , Adulto Jovem
6.
G Chir ; 38(3): 147-148, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29205146

RESUMO

Extra-gonadal choriocarcinoma is an extremely rare highly malignant neoplasm with a poor prognosis. In the gastrointestinal tract it usually arises in stomach, esophagous, bowel intestine and colon. Only few cases are pure and not associated with a classic adenocarcinoma. The correlation of Crohn's disease with choriocarcinoma is not reported. We describe a case of 47-year old man with primary choriocarcinoma of the colon in a previously documented Crohn's disease.


Assuntos
Coriocarcinoma/etiologia , Neoplasias do Colo/etiologia , Doença de Crohn/complicações , Coriocarcinoma/patologia , Neoplasias do Colo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
Monaldi Arch Chest Dis ; 77(2): 102-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23193847

RESUMO

A 57-year-old woman underwent an enucleoresection of her right kidney angiomyolipoma. Two weeks later she was admitted to our hospital because of dyspnea at rest with orthopnea. The chest x-ray showed the elevation of both hemidiaphragms and the measurement of the sniff transdiaphragmatic pressure confirmed the diagnosis of bilateral diaphragmatic paralysis. A diaphragm paralysis can be ascribed to several causes, i.e. trauma, compressive events, inflammations, neuropathies, or it can be idiopathic. In this case, it was very likely that the patient suffered from post-surgery neuralgic amyotrophy. To our knowledge, there are only a few reported cases of neuralgic amyotrophy, also known as Parsonage-Turner Syndrome, which affects only the phrenic nerve as a consequence of a surgery in an anatomically distant site.


Assuntos
Neurite do Plexo Braquial/complicações , Diafragma/inervação , Nefrectomia/efeitos adversos , Nervo Frênico/lesões , Paralisia Respiratória/etiologia , Angiomiolipoma/cirurgia , Neurite do Plexo Braquial/diagnóstico , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Renais/cirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Radiografia Torácica , Testes de Função Respiratória , Paralisia Respiratória/diagnóstico
9.
Eur J Clin Microbiol Infect Dis ; 31(10): 2851-61, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22644053

RESUMO

Symptoms of acute febrile respiratory tract infection are often unspecific, but the rapid identification of pathogens allows optimised patient management. The objective of this study was to evaluate a novel multiplex polymerase chain reaction (PCR) suspension microarray which detects 19 viral and four atypical bacterial targets. A comprehensive set of sensitive monoplex real-time PCR assays was used for each pathogen as the gold standard. A panel of archived as well as 300 prospectively collected clinical samples was analysed by both methods. At least one target was detected in 165/300 (55 %) samples by monoplex PCR and in 140/300 (46 %) samples by multiplex PCR, respectively. The positivity rate was significantly higher in paediatric patients compared to adults [126/154 (82 %) vs. 39/146 (27 %) by monoplex and 114/154 (74 %) vs. 26/146 (18 %) by multiplex PCR, respectively]. Among all samples, 17/300 (5.6 %) were positive for atypical bacteria by monoplex and 8/300 (2.6 %) by multiplex PCR, respectively. Multiple detections were recorded in 35/300 (11.6 %) samples by monoplex and 26/300 (8.7 %) by multiplex PCR. For the most common pathogens, the sensitivity ranged from 57 to 93 % and the specificity ranged from 95 to 100 %. The overall concordance between both methods was 77 % [95 % confidence interval (CI) 72-81 %]. False-negative results by multiplex PCR were mainly due to the low target concentration. Compared to monoplex PCR, the novel microarray assay proved its principle but displayed overall lower sensitivities, potentially restricting its use to paediatric patients. For some targets, only small numbers of positive samples were available, requiring larger studies to firmly assess the sensitivity and specificity.


Assuntos
Bactérias/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Doenças Nasofaríngeas/diagnóstico , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Vírus/isolamento & purificação , Adulto , Bactérias/classificação , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Criança , Pré-Escolar , Intervalos de Confiança , Humanos , Lactente , Doenças Nasofaríngeas/microbiologia , Doenças Nasofaríngeas/virologia , Nasofaringe/microbiologia , Nasofaringe/virologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Viroses/diagnóstico , Viroses/virologia , Vírus/classificação , Adulto Jovem
11.
J Clin Microbiol ; 44(6): 2300-3, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16757646

RESUMO

Human metapneumovirus (HMPV) was isolated from a 63-year-old multiple myeloma patient who had undergone hematopoietic stem cell transplantation and who presented with lower respiratory tract infection several weeks prior to the diagnosis of lung cancer. The isolate was phylogenetically and biologically characterized and compared to HMPV prototypes and recent pediatric isolates. Remarkably, it belonged to the novel genomic subgroup A2b.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias Pulmonares/complicações , Metapneumovirus/isolamento & purificação , Mieloma Múltiplo/complicações , Infecções por Paramyxoviridae/virologia , Infecções Respiratórias/virologia , Animais , Linhagem Celular , Chlorocebus aethiops , Evolução Fatal , Humanos , Masculino , Metapneumovirus/classificação , Metapneumovirus/genética , Pessoa de Meia-Idade , Infecções por Paramyxoviridae/diagnóstico , Filogenia , Infecções Respiratórias/diagnóstico , Células Vero , Replicação Viral
12.
Curr Top Microbiol Immunol ; 277: 161-80, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12908772

RESUMO

Foamy viruses (FVs) are common apathogenic retroviruses readily spread by horizontal transmission in nonhuman primate and some other mammalian host populations. Primate FV infections have been known for half a century, i.e., 15 years before the definition of retroviruses and another 15 years before the detection of primate immune deficiency viruses. The emerging interest in human retroviruses included primate FV, and although the role of human hosts for FV was greatly overestimated temporarily, enthusiastic researchers compiled invaluable data on molecular biology and classic as well as molecular epidemiology of these viruses. It has been shown that lytic FV infection in a wide range of cell cultures is in great contrast to the silent state of the infection in animals. Once transmitted by saliva via biting, FVs reside in all tissues as DNA copies, but their replication is untraceable except in oral submucosal cells, which are thought to supply the virus for transmission. FVs have not definitely been associated with any disease, regardless of viral phylogenetic differences. Various primate and nonprimate species have been used for studies on the natural carrier state and primary infection. Experimental infections have mostly proven to be inefficient in primates as well as lower laboratory animals. However, investigation of the immune response in FV-infected animals has only partly explained the control of FV replication in the animal host. Thus, the biological role of FV remains an enigma to be resolved in the future.


Assuntos
Infecções por Retroviridae/veterinária , Spumavirus/fisiologia , Animais , Linhagem Celular , Haplorrinos , Camundongos , Modelos Animais , Filogenia , Coelhos , Infecções por Retroviridae/epidemiologia , Infecções por Retroviridae/imunologia , Infecções por Retroviridae/transmissão , Spumavirus/classificação , Spumavirus/isolamento & purificação , Replicação Viral
13.
Scand J Immunol ; 56(5): 448-55, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12410794

RESUMO

The protective activity of a DNA plasmid encoding the immunodominant capsid protein VP1 of coxsackievirus B4 (CBV-4) was studied in BALB/c mice. The plasmid pCI-B4-1-c - which gave the highest expression level of VP1 in cultured monkey and human cells - was chosen for immunization. Two injections of pCI-B4-1-c (1 month apart) into the regenerating mouse muscle tissue induced a specific antibody response to CBV-4, as shown by immunoenzyme and neutralization assays. Upon challenge with live CBV-4, the mortality rate of mice vaccinated with the recombinant plasmid was significantly reduced (21% versus >58%) as compared with that of mice that had been either nontreated or injected with a control plasmid devoid of the insert. The VP1-based vaccine, however, did not provide complete protection as - after virus challenge - moderate viraemia occurred together with modest plasma elevations of pathogenesis-related enzymes (amylase and creatine kinase). Yet, immunofluorescence of the small intestine and heart did confirm the protective effect of the VP1-encoding vaccine. In order to obtain a more complete protection against CBV-4, it may be beneficial to immunize mice with combinations of separate DNA plasmids encoding not only VP1 but also the VP2 and VP3 capsid proteins.


Assuntos
Proteínas do Capsídeo/imunologia , Enterovirus Humano B/imunologia , Vacinas de DNA/farmacologia , Vacinas Virais/farmacologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Células COS , Proteínas do Capsídeo/genética , Linhagem Celular , Enterovirus Humano B/genética , Enterovirus Humano B/patogenicidade , Enterovirus Humano B/fisiologia , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/prevenção & controle , Humanos , Cinética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/genética , Vacinas de DNA/genética , Vacinas Virais/genética , Replicação Viral
14.
J Virol ; 73(11): 9256-65, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10516034

RESUMO

The genetic variability of the envelope surface domain (SU) of simian foamy virus (FV) of African green monkeys was studied. To assess the interindividual diversity of FV, isolates were obtained from 19 animals living together in a monkey house. The monkeys had been imported from Kenya prior to being placed in long-term housing in the research institute. In addition, a simian FV isolate and proviral DNA were obtained from an animal caretaker infected in this setting. DNA of the complete SU (1779 to 1793 bp) was analyzed by PCR and sequencing. The sequences revealed four clusters with high homologies (>95%). Between the clusters, divergencies ranged from 3 to 25%. Obviously, the clusters reflect four different strains or subtypes of simian FV type 3 that were prevalent in the colony. In contrast to lentiviruses, hypervariable regions could not be detected in the FV SU. Furthermore, to analyze the intraindividual diversity of FV, we investigated the virus population within an individual monkey at a given time point and its evolution over 13 years. For this purpose, 22 proviral SU clones generated by PCR from one oral swab and seven isolates obtained from the same animal between 1982 and 1995 were examined. These sequences revealed exceptionally high homology rates (99.5 to 100%), and only a minimal genetic drift was recognized within the series of isolates. In conclusion, the low in vivo divergency of FV SU suggests that genetic variability is not important for the maintenance of FV persistence.


Assuntos
Chlorocebus aethiops/virologia , Variação Genética , Doenças dos Macacos/virologia , Infecções por Retroviridae/veterinária , Spumavirus/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Clonagem Molecular , Genes env/genética , Humanos , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Estrutura Terciária de Proteína , Infecções por Retroviridae/virologia , Análise de Sequência de DNA , Spumavirus/isolamento & purificação , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
15.
Virology ; 257(1): 7-14, 1999 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10208915

RESUMO

Foamy viruses (FV), retroviruses of the genus Spumavirus, are able to infect a wide variety of animal species and replicate in nearly all types of cultured cells. To identify the cells targeted by FV in the natural host and define the sites of viral replication, multiple organs of four African green monkeys naturally infected with simian FV type 3 were investigated for the presence of FV proviral DNA and viral transcripts. All organs contained significant amounts of FV proviral DNA. In addition to proviruses containing the complete transactivator gene taf, proviral genomes carrying a specific 295-bp deletion in the taf gene were detected in all monkeys. As in the case of human foamy virus the deletion leads to the formation of the bet gene that is regarded to be instrumental in the regulation of viral persistence. FV RNA was detected by RT-PCR and in situ hybridization only in the oral mucosa of one monkey. No other samples contained detectable levels of viral transcripts. Histopathological changes were not observed in any of the tissue samples analyzed. Our results show that the natural history of FV is characterized by latent infection in all organs of the host and by minimal levels of harmless viral replication in the oral mucosa. The broad host cell range in vivo further encourages the development of FV-derived vectors for therapeutic gene delivery.


Assuntos
Chlorocebus aethiops/virologia , Mucosa Bucal/virologia , Provírus , Spumavirus/fisiologia , Latência Viral , Replicação Viral , Animais , DNA Viral/análise , Proteínas de Ligação a DNA/genética , Humanos , Hibridização In Situ , Reação em Cadeia da Polimerase/veterinária , RNA Viral/análise , Proteínas dos Retroviridae/genética , Spumavirus/patogenicidade , Transativadores/genética
16.
J Virol ; 73(2): 1724-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9882388

RESUMO

The activation of human peripheral blood lymphocytes by mitogens or by triggering the T-cell receptor with anti-CD3 antibodies leads to the production of a potent soluble inhibitory activity against foamy virus-induced cytopathic effects in vitro. The inhibitory activity acts in a species-specific manner. As a consequence, the isolation of foamy viruses from blood lymphocytes of infected humans is accelerated in a heterologous coculture system. Antibodies against gamma interferon (IFN-gamma) are able to suppress most of the inhibitory activity, suggesting that IFN-gamma is the dominant component.


Assuntos
Interferon gama/imunologia , Linfócitos/imunologia , Spumavirus/imunologia , Células 3T3 , Animais , Linhagem Celular , Cricetinae , Efeito Citopatogênico Viral , Haplorrinos , Humanos , Camundongos , Spumavirus/fisiologia
17.
Pa Med ; 102(12): 15, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10641526
18.
J Med Virol ; 54(1): 44-53, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9443108

RESUMO

In vitro experiments indicate that components of the host present in body fluids may prevent the attachment of human immunodeficiency virus type 1 (HIV-1) to target cells. Fibronectin (Fn), a dimeric 440-kDa extracellular matrix adhesion protein, is secreted by mesenchymal cells and assembled into insoluble matrices. Fn exerts important effects on cell growth and differentiation through a number of discrete functional domains. Several microorganisms are known to bind Fn. We show that, under physiological conditions, HIV-1 gp120 and gp160 are capable of binding plasma and cellular Fn as well as laminin and vitronectin. Experiments were set up to analyze in detail the binding of HIV gp120 and gp160 to Fn. The gp120 and gp160 specifically recognize the C-terminal heparin-binding domain of Fn (Fn-CTHBD) with a calculated KD of 2.8 x 10(-7) M for gp160. Binding of gp160 to Fn-CTHBD is a saturable and specific process that is blocked by antibodies to Fn-CTHBD and by heparin and is inhibited to a minor extent by heparan sulfate and dextran sulfate. These observations suggest that gp120/160 specifically recognize the III15 repeat within Fn-CTHBD. Intact Fn and Fn-CTHBD strongly inhibit the interaction of gp120/160 with soluble CD4 and, under low serum conditions, are capable of neutralizing the infectivity of HIV-1 for CD4-positive T cells. Thus, Fn that is present in plasma and mucinous secretions may well affect HIV infectivity and virus distribution in vivo.


Assuntos
Fibronectinas/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Proteína gp160 do Envelope de HIV/metabolismo , HIV-1/metabolismo , Anticorpos/farmacologia , Western Blotting , Antígenos CD4/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Fibrinogênio/metabolismo , Fibronectinas/química , Fibronectinas/imunologia , Fibronectinas/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Heparina/farmacologia , Humanos , Cinética , Laminina/metabolismo , Orosomucoide/metabolismo , Especificidade por Substrato , Linfócitos T/virologia , Vitronectina/metabolismo , alfa-Fetoproteínas/metabolismo
19.
Clin Exp Immunol ; 109(1): 80-3, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9218828

RESUMO

Mycobacterium tuberculosis H37Rv and H37Ra were derived from the same parental strain but differ strikingly in their virulence for experimental animals. Transfer of genetic material between these closely related strains resulted in the isolation of a number of recombinant H37Ra clones bearing the in vivo growth-promoting ivg locus of H37Rv. The recombinant strain was phagocytosed by murine peritoneal macrophages infected in vivo or in vitro and their intracellular growth rates were compared with the vector control. The intracellular growth of the recombinant was significantly faster than the vector control, but substantially slower than the wild-type H37Rv control, regardless of the method used to infect the macrophages. The slower intracellular growth observed for the recombinant strains was not due to a genetically induced metabolic defect, since they grew in synthetic liquid medium at rates equal to those observed for both H37Rv and H37Ra. Peritoneal macrophage monolayers provide a rapid and convenient assay by which to screen H37Ra recombinants for the presence of putative virulence genes.


Assuntos
Macrófagos Peritoneais/microbiologia , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/genética , Recombinação Genética , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/patogenicidade , Fagocitose , Organismos Livres de Patógenos Específicos , Virulência
20.
J Virol ; 71(6): 4821-4, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9151878

RESUMO

Evidence for natural foamy virus (FV) infections in humans is still lacking. However, accidental infections of humans with simian FV have been demonstrated by serology and PCR, but all previous attempts to recover infectious virus in such cases have failed. Here we describe the isolation of a simian FV from peripheral blood mononuclear cells (PBMC) of a healthy animal caretaker, who acquired the virus 20 years ago from an African green monkey (AGM) bite. Properties of the human isolate such as host range in cell cultures including human PBMC and ability to induce neutralizing antibodies in the primate host proved to be similar to those of FV obtained from AGM. The genomic sequence of the isolate was found to be virtually identical to the proviral sequence present in the host lymphocytes and related to AGM isolates but distinct from those of all FV isolates handled in the laboratory. For successful virus isolation, it was essential to stimulate the host lymphocytes by phytohemagglutinin and interleukin-2 for 2 weeks prior to cocultivation with permissive cells. In contrast to the situation found in FV-infected monkeys, virus isolation from the saliva of the animal caretaker was not possible, and no evidence for FV transmission to family contacts was obtained. We conclude that, in contrast to active infection in monkeys, FV persists in a state of latency following accidental infection of humans.


Assuntos
Chlorocebus aethiops/microbiologia , Infecções por Retroviridae/microbiologia , Spumavirus/isolamento & purificação , Acidentes , Animais , Anticorpos Antivirais/análise , Mordeduras e Picadas/microbiologia , Células Cultivadas , Humanos , Exposição Ocupacional , Filogenia , Infecções por Retroviridae/etiologia , Homologia de Sequência do Ácido Nucleico , Fatores de Tempo
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