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1.
Science ; 234(4782): 1388-91, 1986 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-3787251

RESUMEN

The presurface (preS) proteins of hepatitis B virus are structural components of the viral envelope that may play important roles in virion assembly and infectivity. They are specified by a large open reading frame that includes the coding region for the major surface (S) protein in its 3' half. Translation of the preS proteins initiates upstream from the S region, giving rise to proteins that are composed of the S domain and an additional 163 (preS1) or 55 (preS2) amino acids. Little is known about the biosynthesis and assembly of these proteins. The expression of the S and preS1 proteins was examined by transfecting cultured mammalian cells with viral DNA and injecting synthetic messenger RNA's into Xenopus oocytes. In contrast to the proteins encoded by the S region, the preS1 proteins are not detectably secreted into the culture medium. Furthermore, when the S and preS1 proteins are synthesized together, secretion of the S proteins is specifically and strongly inhibited. The results suggest a unique molecular interaction during secretion of the S and preS proteins that may be important for virus assembly.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/metabolismo , Antígenos de Superficie de la Hepatitis B/farmacología , Precursores de Proteínas/farmacología , Animales , ADN Viral/administración & dosificación , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/patogenicidad , Biosíntesis de Proteínas , Precursores de Proteínas/genética , Virión/patogenicidad , Replicación Viral , Xenopus
2.
Science ; 249(4975): 1420-3, 1990 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-2402635

RESUMEN

In order to investigate the potential for Borrelia burgdorferi infection before the recognition of Lyme disease as a clinical entity, the polymerase chain reaction (PCR) was used to examine museum specimens of Ixodes dammini (deer ticks) for the presence of spirochete-specific DNA sequences. One hundred and thirty-six archival tick specimens were obtained representing various continental U.S. locations; DNA sequences characteristic of modern day isolates of B. burgdorferi were detected in 13 1940s specimens from Montauk Point and Hither Hills, Long Island, New York. Five archival specimens of Dermacentor variabilis (dog tick) from the same collection and 118 Ixodes specimens from other endemic and nonendemic sites were negative. These data suggest that the appearance of the Lyme disease spirochete in suitable arthropod vectors preceded, by at least a generation, the formal recognition of this disease as a clinical entity in the United States.


Asunto(s)
Grupo Borrelia Burgdorferi/aislamiento & purificación , ADN Bacteriano/aislamiento & purificación , Garrapatas/microbiología , Animales , Secuencia de Bases , Grupo Borrelia Burgdorferi/genética , ADN Bacteriano/genética , Perros , Genes Bacterianos , Humanos , Enfermedad de Lyme/microbiología , Datos de Secuencia Molecular , Museos , New York
3.
J Clin Invest ; 97(4): 1028-34, 1996 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-8613525

RESUMEN

The effect of anti-interleukin (IL-12 treatment on Lyme borreliosis in C3H/HeN (C3H) mice was assessed because other studies have implicated CD4+ T cell helper (Th) type 1 responses in the genesis of disease caused by Borrelia burgdorferi. Infection of inbred mice with B. burgdorferi results in varying degrees of arthritis: BALB/c mice develop mild disease and C3H mice develop severe arthritis that is most pronounced 2-4 wk after infection. Since IL-12 is a major inducer of Th1 responses, we blocked this cytokine in vivo in B. burgdorferi infected C3H mice, and evaluated the effects of treatment on the development of arthritis at the peak of acute joint inflammation (14 d) and in the resolution phase (60 d) of disease. As expected, intraperitoneal administration of an anti-IL-12 monoclonal antibody (mAb) to C3H mice resulted in a decrease in both IFN-gamma and B. burgdorferi-specific IgG2a in serum, indicative of diminished Th1 responses. No IL-4 production was detected in serum of anti-IL-12 mAb treated or control mice. IgG1 and IgG2b levels did not increase in B. burgdorferi infected mice treated with anti-IL-12 mAb compared with controls suggesting that Th2 responses were not affected. Nevertheless, CD4+ T cells from both control and anti-IL-12 mAb treated mice had similar in vitro responses to B. burgdorferi antigens. Treatment with anti-IL-12 mAb produced a significant reduction in peak arthritis severity, and an increase in the number of spirochetes in ear tissue. These data show that treatment of B. burgdorferi infected mice with anti-IL-12 mAb results in a reduction of the Th1 and/or innate immune responses in vivo and a reduction in the severity of acute murine Lyme arthritis.


Asunto(s)
Interleucina-12/uso terapéutico , Enfermedad de Lyme/terapia , Animales , Borrelia/crecimiento & desarrollo , Linfocitos T CD4-Positivos/inmunología , Femenino , Inmunoglobulina G/inmunología , Interferón gamma/fisiología , Enfermedad de Lyme/microbiología , Activación de Linfocitos , Ratones , Ratones Endogámicos C3H , Células TH1/inmunología
4.
Mol Cell Biol ; 2(9): 1096-103, 1982 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6983647

RESUMEN

We investigated the mechanism of action of 2-aminopurine (Apur) in eucaryotic cells. By analogy with studies in procaryotic systems, the base analog is presumed to incorporate into DNA predominantly opposite T where, upon subsequent DNA replication, it can mispair with C, inducing an A:T leads to G:C transition. This model predicts that Apur-induced mutagenesis will be enhanced by factors that favor formation of Apur-C mispairs, e.g., high levels of dCTP or low levels of TTP. We describe the use of a mutant T-lymphosarcoma cell line, AraC-6-1, which has an abnormally high dCTP pool and a low TTP pool, to test this prediction. AraC-6-1 cells were three- to fivefold more mutable by Apur than their parental cell line, NSU-1. This enhanced mutability by Apur could not be explained by altered incorporation of 3H-labeled Apur, by generally impaired ability to repair DNA damage, or by a direct effect of Apur on the endogenous deoxynucleotide pools. The addition of 10 microM thymidine to the growth medium of AraC-6-1 cells lowered their high dCTP pool (two- to threefold), raised the TTP pool (two- to threefold), and abolished their enhanced mutability by Apur. Further manipulation to produce an abnormally high TTP/dCTP ratio suppressed Apur-induced mutagenesis (8- to 10-fold) in both AraC-6-1 and NSU-1 cells. These observations support the hypothesis that Apur induces A:T leads to G:C transitions in mammalian cells by a mispairing mechanism.


Asunto(s)
2-Aminopurina/farmacología , Adenina/análogos & derivados , ADN/biosíntesis , Linfocitos T/metabolismo , Animales , Secuencia de Bases/efectos de los fármacos , Línea Celular , Citidina Trifosfato/metabolismo , Reparación del ADN , Replicación del ADN/efectos de los fármacos , Linfoma no Hodgkin , Ratones , Mutágenos , Linfocitos T/efectos de los fármacos , Nucleótidos de Timina/metabolismo
5.
Curr Opin Microbiol ; 2(3): 299-305, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10383862

RESUMEN

Conventional methods for the identification and characterization of clinical isolates of bacterial pathogens sometimes fall short when such isolates exhibit unusual phenotypic profiles. Recent advances in DNA sequencing technology have greatly enhanced the ability of the microbiologist to determine the identity of a bacterial isolate. Given the relative objectivity of DNA sequence information and growing availability of sequence information databases, a significant movement is now afoot to use molecular methods for the identification of clinical pathogens.


Asunto(s)
Bacterias/genética , ADN Ribosómico/genética , Análisis de Secuencia de ADN , Bacterias/química , Bacterias/clasificación , Secuencia de Bases , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , Humanos , ARN Ribosómico 16S/genética
6.
Cancer Res ; 60(21): 5916-21, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11085503

RESUMEN

The development of cervical cancer is highly associated with human papillomavirus (HPV) infection. HPV integration into the genome of infected cervical cells is temporally associated with the acquisition of the malignant phenotype. A relationship between the sites of HPV integration in cervical cancer and the position of the common fragile sites (CFSs) has been observed at the cytogenetic level. To explore this relationship at the molecular level, we used a PCR-based method to rapidly isolate cellular sequences flanking the sites of HPV16 integrations in primary cervical tumors. Human bacterial artificial chromosome clones were isolated based on these flanking sequences and used as probes for fluorescence in situ hybridization on metaphases derived from cells cultured in the presence of aphidicolin. Our data demonstrate that HPV16 integrations in cervical tumors frequently occur within CFSs at the molecular level. In addition, we have determined the precise molecular locations of the CFSs FRA6C and FRA17B.


Asunto(s)
Carcinoma de Células Escamosas/virología , Fragilidad Cromosómica/genética , Papillomaviridae/genética , Neoplasias del Cuello Uterino/virología , Integración Viral/genética , Secuencia de Bases , Carcinoma de Células Escamosas/genética , Sitios Frágiles del Cromosoma , Cromosomas Artificiales Bacterianos , Cromosomas Humanos/genética , Clonación Molecular , ADN de Neoplasias/genética , ADN Viral/genética , Femenino , Humanos , Datos de Secuencia Molecular , Papillomaviridae/clasificación , Reacción en Cadena de la Polimerasa , Neoplasias del Cuello Uterino/genética
7.
Oncogene ; 20(53): 7699-709, 2001 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-11753648

RESUMEN

Using a combination of cDNA subtraction and microarray analysis, we report here the identification and characterization of L552S, an over-expressed, alternatively spliced isoform of XAGE-1 in lung adenocarcinoma. Real-time RT-PCR analysis shows that L552S is expressed at levels greater than 10-fold in 12 of 25 lung adenocarcinoma tumors compared with the highest expression level found in all normal tissues tested. L552S is expressed in both early and late stages of lung adenocarcinoma, but it was not detected in large cell carcinoma, small cell carcinoma, or atypical lung neuroendocrine carcinoid. The full-length cDNA for L552S comprises 770 bp and encodes a polypeptide of 160 amino acids. C-terminal 94 amino acids of L552S are identical to a cancer testis antigen, XAGE-1, found in Ewing's sarcoma. Genomic sequence analysis has revealed that L552S and XAGE-1 are alternatively spliced isoforms, and expression of both L552S and XAGE-1 isoforms are present in lung adenocarcinoma. Immunohistochemistry analysis using affinity purified L552S polyclonal antibodies demonstrated specific nuclear staining in 10 of 12 lung adenocarcinoma samples. Furthermore, antibody responses to recombinant L552S protein were observed in seven of 17 lung pleural effusion fluids of lung cancer patients. These results strongly imply that L552S protein is immunogenic and suggest that it might have use as a vaccine target for lung cancer.


Asunto(s)
Adenocarcinoma/genética , Empalme Alternativo/genética , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Secuencia de Aminoácidos , Secuencia de Bases , Western Blotting , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Núcleo Celular/metabolismo , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia , Cromosoma X/genética
8.
Arch Intern Med ; 161(16): 2015-20, 2001 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-11525704

RESUMEN

BACKGROUND: The present recommendation for the serologic diagnosis of Lyme disease is a 2-tier process in which a serum sample with a positive or equivocal result by an enzyme-linked immunosorbent assay (ELISA) or immunofluorescent assay is then followed by supplemental testing by Western blot. Our laboratory has developed recombinant chimeric proteins composed of key Borrelia epitopes. These novel antigens are consistent and are easily standardized. METHODS: We adapted these recombinant proteins into a new immunochromatographic format that can be used as a highly sensitive and specific first-tier assay that can be used to replace the ELISA or immunofluorescent assay. RESULTS: This rapid test was equally sensitive (P>.05) and more specific (P<.05) than a frequently used commercial whole cell ELISA. The overall clinical accuracy achieved on agreement studies among 3 Lyme research laboratories on clinically defined serum panels was shown to be statistically equivalent to the commercial ELISA. The assay can detect anti-Borrelia burgdorferi antibodies in either serum or whole blood. CONCLUSION: This sensitive and specific rapid assay, which is suited for the physician's office, streamlines the 2-tier system by allowing the physician to determine if a Western blot is necessary at the time of the initial office visit.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Infecciones por Borrelia/diagnóstico , Grupo Borrelia Burgdorferi/inmunología , Cromatografía , Epítopos/análisis , Proteínas Recombinantes de Fusión/análisis , Western Blotting , Infecciones por Borrelia/inmunología , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Humanos , Sensibilidad y Especificidad
9.
Am J Med ; 100(5): 548-54, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8644768

RESUMEN

PURPOSE: To assess possible triggers and cofactors for chronic fatigue syndrome (CFS) and to compare levels of selected cytokines between cases and an appropriately matched control group. PATIENTS AND METHODS: We conducted a case-control study of 47 cases of CFS obtained through a regional CFS research program maintained at a tertiary care medical center. One age-, gender-, and neighborhood-matched control was identified for each case through systematic community telephone sampling. Standardized questionnaires were administered to cases and controls. Sera were assayed for transforming growth factor-beta (TGF-beta), interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, and antibody to Borrelia burgdorferi and Babesia microti. RESULTS: Cases were more likely to have exercised regularly before illness onset than controls (67% versus 40%; matched odds ratio (MOR) = 3.4; 95% CI = 1.2 to 11.8; P = 0.02). Female cases were more likely to be nulliparous prior to onset of CFS than controls (51% versus 31%; MOR = 8.0; 95% CI = 1.03 to 170; P = 0.05). History of other major factors, including silicone-gel breast implants (one female case and one female control), pre-morbid history of depression (15% of cases, 11% of controls) and history of allergies (66% of cases, 51% of controls) were similar for cases and controls. However, cases were more likely to have a diagnosis of depression subsequent to their diagnosis of CFS compared to a similar time frame for controls (MOR = undefined; 95% CI lower bound = 2.5; P < 0.001). Positive antibody titers to B burgdorferi (one case and one control) and B microti (zero cases and two controls) were also similar. CONCLUSIONS: Further investigation into the role of prior routine exercise as a cofactor for CFS is warranted. This study supports the concurrence of CFS and depression, although pre-morbid history of depression was similar for both groups.


Asunto(s)
Síndrome de Fatiga Crónica/etiología , Adolescente , Adulto , Anciano , Animales , Anticuerpos Antibacterianos/análisis , Anticuerpos Antiprotozoarios/análisis , Babesia/inmunología , Grupo Borrelia Burgdorferi/inmunología , Estudios de Casos y Controles , Interpretación Estadística de Datos , Depresión/complicaciones , Síndrome de Fatiga Crónica/sangre , Femenino , Humanos , Hipersensibilidad/complicaciones , Interleucina-1/sangre , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Paridad , Esfuerzo Físico , Factores de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo , Factor de Crecimiento Transformador beta/sangre , Factor de Necrosis Tumoral alfa/análisis
10.
Transplantation ; 67(9): 1251-5, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10342317

RESUMEN

BACKGROUND: A porcine endogenous retrovirus (PERV) capable of infecting human cells has been identified. This study was designed to determine whether hollow fiber membranes, such as those used in a bioartificial liver, block the transfer of PERV. METHODS: Three hollow fiber cartridges (HFCs) were studied in duplicate: cellulose fibers with 70 kD nominal molecular weight cut-off (MWCO), polysulfone fibers with 400 kD MWCO, and mixed cellulose fibers with 200 nm porosity. PK15 cells (porcine kidney cell line), known to produce PERV, were grown in the intraluminal compartment of HFCs fiber cartridges. Samples of medium were collected from both intraluminal and extraluminal compartments of the HFCs fiber cartridge during 14 days of culture. Samples were screened for PERV using reverse transcription polymerase chain reaction. All positive samples were tested for PERV infectivity in human 293 cells. RESULTS: PERV was detected in all samples from the intraluminal space and all intraluminal samples seemed to infect 293 cells. All extraluminal samples from the fibers of 200 nm porosity tested positive for PERV. Detection of PERV in the extraluminal space was delayed by fibers of 400 kD MWCO and 70 kD MWCO until at least day 3 and day 7, respectively, after inoculation of PK15 cells. Positive extraluminal samples from fibers of 400 kD MWCO and 70 kD MWCO did not infect 293 cells. CONCLUSION: Pore size, membrane composition, and duration of exposure influenced the transfer of PERV across HFCs. Some HFCs decrease the risk of viral exposure to patients during bioartificial liver therapy.


Asunto(s)
Retrovirus Endógenos , Membranas Artificiales , Porcinos/virología , Animales , Órganos Artificiales , Línea Celular , Celulosa , ADN Viral/análisis , Humanos , Riñón/virología , Polímeros , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sulfonas
11.
Transplantation ; 65(1): 73-6, 1998 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9448147

RESUMEN

BACKGROUND: The significance of hepatitis G (HGV) infection in liver transplant recipients is not known. We set out to determine the pre-orthotopic liver transplantation (OLT) prevalence, the pre- and postoperative viral titers of HGV, and the allograft histology in patients infected with HGV who underwent OLT for cryptogenic cirrhosis. METHODS: HGV RNA was measured using a research-based branched DNA assay. The assay used a target-specific probe set that was based on the 5'-untranslated region of the HGV genome. Allograft histology was assessed with protocol liver biopsies in all patients who survived longer than 6 months. RESULTS: The preoperative prevalence of HGV infection in recipients transplanted for cryptogenic cirrhosis was 26%. Thirty-seven percent (12 of 33) of recipients who had serum available in the first postoperative month had HGV infection. Mean HGV RNA levels were 9.8 (+/-4.2) (viral molecular equivalents/ml x 10[6]) before OLT and 37.5 (+/-10.7) at 1 year after OLT. In 4 of the 11 cryptogenic recipients in whom HGV RNA was detectable in the first postoperative month, HGV RNA fell to undetectable levels at the most recent follow-up (mean 70 months). Of the five cryptogenic recipients who continue to have measurable HGV RNA, three have unexplained hepatitis histologically. CONCLUSIONS: These findings suggest the following: 1) The prevalence of HGV infection in patients undergoing OLT for cryptogenic cirrhosis is about 25%. 2) In recipients persistently infected with HGV, mean HGV RNA titers increase after OLT. 3) HGV RNA becomes undetectable in about one third of recipients who had detectable HGV RNA in the first month after OLT. 4) Hepatitis of uncertain etiology occurs in 60% (3 of 5) of persistently HGV-infected cryptogenic recipients.


Asunto(s)
Flaviviridae , Hepatitis Viral Humana/transmisión , Cirrosis Hepática/terapia , Trasplante de Hígado , Adulto , ADN Viral/análisis , Femenino , Flaviviridae/genética , Hepatitis Viral Humana/complicaciones , Hepatitis Viral Humana/epidemiología , Humanos , Cirrosis Hepática/complicaciones , Masculino , Persona de Mediana Edad , Prevalencia
12.
Mayo Clin Proc ; 71(5): 458-62, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8628025

RESUMEN

OBJECTIVE: To review the geographic distribution and current understanding of hepatitis C virus (HCV) genotypes in regard to liver disease activity and response to treatment. MATERIAL AND METHODS: We review the relevant medical literature and discuss our recent findings relative to chronic HCV infection and the importance of HCV genotypes. RESULTS: HCV genotypes 1a and 1b are the most commonly found genotypes in patients with chronic HCV in the United States. Infection with HCV genotype 1b may be associated with more severe liver disease and may have a higher risk for the development of hepatocellular carcinoma. HCV genotype 2b seemed to be the most sensitive and HCV genotype 1b was the least sensitive to interferon therapy. CONCLUSION: The identification of the infectious HCV genotype may be beneficial in clinical settings and may assist in the selection of patients who would benefit from interferon treatment.


Asunto(s)
Hepacivirus/genética , Hepatitis C/epidemiología , Genoma Viral , Genotipo , Hepacivirus/clasificación , Hepatitis C/virología , Humanos , Análisis de Secuencia de ARN , Estados Unidos/epidemiología
13.
Mayo Clin Proc ; 70(5): 449-52, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7537347

RESUMEN

OBJECTIVE: To evaluate the serologic reactivities in patients infected with different hepatitis C virus (HCV) genotypes to four HCV proteins that are components of the second-generation recombinant immunoblot assay. MATERIAL AND METHODS: Serum samples from 36 patients with chronic HCV infection were obtained. RNA was extracted by using chaotropic lysis and isopropanol precipitation. Reverse-transcriptase polymerase chain reaction of the NS-5 region was performed, followed by automated single-pass dideoxy sequencing of desalted amplification products. Classification of isolated HCV subtypes was based on Simmonds' system. All samples were tested for antibodies to proteins 5-1-1, C100-3, C33c, and C22-3 with the second-generation recombinant immunoblot assay. RESULTS: Reactivity to protein 5-1-1 was significantly lower for patients with genotypes 2b and 3a than for those infected with HCV types 1a or 1b (P < 0.05). Antibody reactivity to the C100-3 protein was also reduced in patients infected with HCV types 2b and 3a. CONCLUSION: These data indicate that the genotype-dependent differences in serologic reactivities are substantial among patients with chronic HCV infection.


Asunto(s)
Hepacivirus/genética , Hepatitis Crónica/virología , Secuencia de Bases , Ensayo de Inmunoadsorción Enzimática , Genotipo , Hepacivirus/clasificación , Anticuerpos Antihepatitis/genética , Anticuerpos contra la Hepatitis C , Humanos , Immunoblotting/métodos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas Virales/inmunología
14.
Mayo Clin Proc ; 74(5): 454-60, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10319074

RESUMEN

OBJECTIVE: To correlate viral genotypes with the immune manifestations of chronic hepatitis C and evaluate the effect of immune features on disease expression and response to antiviral treatment. DESIGN: We undertook a retrospective analysis of 67 patients with chronic hepatitis C. MATERIAL AND METHODS: Patients were selected for study if they had been screened for autoantibodies and concurrent immune diseases and if viral genotyping had been performed or was possible. Concurrent immune manifestations and responses to interferon therapy were determined. RESULTS: Of the 67 patients, 18 (27%) had one or more immune features. Immune manifestations occurred as commonly in patients with genotype 1 as in those with other genotypes (30% versus 14%; P = 0.3). Concurrent immune features did not distinguish patients, and responses to interferon therapy were similar between patients with and those without immune manifestations. None of the 14 patients with concurrent immune diseases or high-titer autoantibodies (serum titers, 1:320 or more) entered remission during interferon treatment. In contrast, 6 of 53 patients without concurrent immune diseases and no or low-titer autoantibodies had treatment-related remission. These differences, however, were not statistically significant (0% versus 11%; P = 0.3). CONCLUSION: Autoantibodies and concurrent immune diseases are not associated with a particular viral genotype, clinical profile, or treatment outcome. Larger studies are necessary for complete assessment of the influence of prominent immune manifestations on treatment response.


Asunto(s)
Autoanticuerpos/sangre , Enfermedades Autoinmunes/inmunología , Hepacivirus/genética , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C Crónica/inmunología , Adulto , Antivirales/uso terapéutico , Enfermedades Autoinmunes/tratamiento farmacológico , Cartilla de ADN , ADN Viral/química , Femenino , Genotipo , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Estudios Retrospectivos
15.
Mayo Clin Proc ; 73(4): 338-41, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9559037

RESUMEN

A 68-year-old woman, who had not traveled outside of western Wisconsin, was hospitalized after 4 weeks of chills, fevers, myalgias, neuralgias in her right arm, and pain in the right upper quadrant of her abdomen. Physical examination revealed hepatosplenomegaly, and laboratory studies showed anemia, thrombocytopenia, increased aspartate transaminase level, and microscopic hematuria. Wright's stain of a blood smear revealed intraerythrocytic organisms consistent with Babesia species. A polymerase chain reaction of whole blood specimens along with an increased serologic titer confirmed the diagnosis of Babesia microti. Indirect immunofluorescent antibody serology and Western blot analysis revealed a simultaneous infection with Borrelia burgdorferi. Coinfection with B. microti and B. burgdorferi may occur in endemic areas where both organisms are carried by the same tick vector, Ixodes scapularis. The intensity and duration of illness seem to be greatest in patients with concurrent infection.


Asunto(s)
Babesiosis/complicaciones , Babesiosis/diagnóstico , Enfermedad de Lyme/complicaciones , Enfermedad de Lyme/diagnóstico , Anciano , Animales , Babesiosis/parasitología , Diagnóstico Diferencial , Femenino , Humanos , Ixodes , Wisconsin
16.
Mayo Clin Proc ; 70(9): 853-62, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7643639

RESUMEN

OBJECTIVE: To describe a case of human babesiosis and review the literature on the disease. MATERIAL AND METHODS: We describe a 62-year-old man with babesiosis, outline his clinical course and response to therapy, and discuss the use of the polymerase chain reaction for the diagnosis and monitoring of the infection. RESULTS: The onset of the disease was insidious, with fatigue, fever, weight loss, intermittently discolored urine, and anemia. Computed tomography of the abdomen revealed a small, shrunken spleen with an irregular border. With treatment, the symptoms gradually resolved. Although peripheral blood smears were negative soon after therapy, Babesia microti DNA was detected by polymerase chain reaction 53 days after initial examination. CONCLUSION: The development of improved methods for diagnosis, including indirect immunofluorescent antibody assays and the polymerase chain reaction, provides more sensitive detection of the parasitemia associated with babesiosis. Use of these methods may help to delineate the complete clinical spectrum of this infection and its geographic distribution in the United States.


Asunto(s)
Babesiosis , Babesiosis/diagnóstico , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
17.
Mayo Clin Proc ; 73(5): 412-8, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9581580

RESUMEN

OBJECTIVE: To assess the frequency and significance of GB virus-C infection in type 1 autoimmune hepatitis. MATERIAL AND METHODS: Serum specimens from 94 patients with type 1 autoimmune hepatitis were tested for GB virus-C RNA by reverse transcription and polymerase chain reaction. Serum samples from 50 normal subjects were also assessed. RESULTS: Three of the 94 specimens from patients with autoimmune hepatitis were positive for GB virus-C RNA in comparison with none of the 50 control samples (3% versus 0%; P = 0.5). Two patients were seropositive after variceal hemorrhage and blood transfusion, including one patient who clearly acquired the infection in this fashion. One patient had no epidemiologic basis for his seropositivity. Viremia was prolonged in all infected patients (mean duration, 69 +/- 23 months; range, 36 to 113); however, no clinical features suggested a concurrent viral infection, and mortality was similar to that among the uninfected counterparts (33% versus 8%; P = 0.2). Liver transplantation was more common in the infected patients (67% versus 9%; P = 0.03), but the duration of disease was also longer in these patients (277 +/- 29 months versus 106 +/- 9 months; P = 0.0008). Clinical features and immediate responses to corticosteroid therapy were similar in both groups. CONCLUSION: GB virus-C RNA is found infrequently in type 1 autoimmune hepatitis, and GB virus-C is unlikely to be an important etiologic agent or prognostic determinant.


Asunto(s)
Flaviviridae , Hepatitis Autoinmune/complicaciones , Hepatitis Viral Humana/complicaciones , Biopsia con Aguja , Flaviviridae/genética , Hepatitis Autoinmune/diagnóstico , Hepatitis Autoinmune/terapia , Hepatitis Viral Humana/diagnóstico , Hepatitis Viral Humana/terapia , Humanos , Hígado/virología , ARN Viral/análisis , Resultado del Tratamiento , Viremia/virología
18.
Mayo Clin Proc ; 71(3): 221-9, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8594278

RESUMEN

OBJECTIVE: To compare molecular techniques with conventional diagnostic methods for evaluating nosocomial transmission of multidrug-resistant tuberculosis (MDR-TB). DESIGN: We conducted a 12-week postexposure inception cohort study of health-care personnel who had been exposed to a patient with MDR-TB. MATERIAL AND METHODS: In addition to baseline and follow-up tuberculin skin tests and chest roentgenography, weekly pulmonary specimens were evaluated by (1) auramine-rhodamine fluorescent staining, (2) culture for mycobacteria, and (3) polymerase chain reaction (PCR) to amplify IS6110, a nucleic acid insertion sequence unique to the Mycobactrium tuberculosis complex. RESULTS: The index patient's isolate of M. tuberculosis showed a mutation in codon 531 of the RNA polymerase beta subunit (rpoB) gene of M. tuberculosis, which is associated with rifampin resistance and considered a marker for this MDR-TB strain. All pulmonary and gastric specimens from study participants had negative auramine stains and cultures for mycobacteria, One person, however, had separate specimens with repeatedly positive PCR results for IS6110 sequences, but the specimens contained a wild-type M. tuberculosis rpoB codon 531 dissimilar from the index patient's strain. CONCLUSION: Although both molecular and conventional testing showed that no exposed person was infected with the MDR-TB strain, molecular test results were available sooner and seemed more sensitive for detecting M. tuberculosis in one exposed person, presumably in a preinfection or "colonized" stage. Molecular methods provided information that helped distinguish this person's M. tuberculosis strain from the index patient's MDR-TB strain. Additional prospective studies should assess the value of these molecular techniques in similar clinical settings.


Asunto(s)
Transmisión de Enfermedad Infecciosa de Paciente a Profesional , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Tuberculosis Resistente a Múltiples Medicamentos/transmisión , Antituberculosos/uso terapéutico , Secuencia de Bases , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , ADN Bacteriano/análisis , Estudios de Evaluación como Asunto , Humanos , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/análisis , Datos de Secuencia Molecular , Mycobacterium tuberculosis/genética , Estudios Prospectivos , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
19.
Res Microbiol ; 146(5): 415-24, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8525058

RESUMEN

The genetic diversity of Borrelia burgdorferi isolates from several geographic regions was evaluated by nucleotide sequence analysis of the genes encoding 23S ribosomal RNA and outer surface protein A. Comparison of nucleotide sequences spanning 738 bp of the 23S ribosomal DNA from two unusual isolates, DN127 (Del Norte County, California) and 25015 (Millbrook, New York), to homologous sequences from other B. burgdorferi isolates from the United States and Russia identified several nucleotide sequence polymorphisms that are unique to these two isolates. Sequence analysis of a 615 nucleotide segment of the gene encoding outer surface protein A also revealed greater similarity of strains DN127 and 25015 (94.1%) compared to other US and Eurasian isolates. These data were further corroborated by genomic macrorestriction analysis, in which DN127 and 25015 demonstrated unique restriction digestion patterns. Our findings suggest that substantial genetic diversity of B. burgdorferi, rivaling that of European strains, exists among isolates from the United States. Strains DN127 and 25015 are unique among all B. burgdorferi isolates tested to date, and though isolated from opposite longitudinal extremes of the North American continent, are closely related.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , Grupo Borrelia Burgdorferi/genética , ADN Bacteriano/química , Reacción en Cadena de la Polimerasa/métodos , ARN Ribosómico 23S/química , Secuencia de Bases , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Técnicas In Vitro , Datos de Secuencia Molecular , ARN Ribosómico 23S/genética , Estados Unidos
20.
J Heart Lung Transplant ; 14(5): 865-9, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8800721

RESUMEN

BACKGROUND: Hepatitis C virus infection is common in organ transplant recipients, and can be associated with significant morbidity and mortality. A unique feature of this infection among immunosuppressed patients is that it can progress without the development of hepatitis C virus antibodies. METHODS: To define the prevalence of hepatitis C virus infection in patients undergoing heart transplantation and identify clinical syndromes associated with hepatitis C virus infection in heart transplant recipients, we collected sera from 59 consecutive heart transplant recipients and their donors. Samples were tested before and after transplantation for hepatitis C virus antibodies with the use of a second-generation recombinant immunoblot assay and for hepatitis C virus RNA by means of reverse transcriptase polymerase chain reaction. RESULTS: Four of 59 patients (7%) had hepatitis C virus-RNA detected in posttransplantation serum samples; but only one of these was anti-hepatitis C virus antibody positive. Two of the four patients with hepatitis C virus RNA detected after transplantation received organs from donors who were positive for hepatitis C virus RNA/anti-hepatitis C virus. One of these two recipients tested positive for hepatitis C virus antibody and hepatitis C virus RNA before transplantation. The other two patients received organs from hepatitis C virus negative donors and possibly acquired infection after transplantation from blood or immunoglobulin preparations. One patient was anti-hepatitis C virus positive before transplantation but had no detectable hepatitis C virus RNA, and hepatitis C virus infection did not develop after transplantation. Progressive hepatitis C virus-induced cholestatic liver disease that led to hepatic failure and death after heart transplantation occurred in one of the four patients. CONCLUSION: Hepatitis C virus infection may occur after heart transplantation in the absence of anti-hepatitis C virus antibodies, and a syndrome of severe cholestatic liver disease may complicate heart transplantation in the presence of hepatitis C virus infection.


Asunto(s)
Trasplante de Corazón , Hepatitis C/diagnóstico , Adulto , Femenino , Trasplante de Corazón/efectos adversos , Hepacivirus/aislamiento & purificación , Hepatitis C/etiología , Anticuerpos contra la Hepatitis C/análisis , Humanos , Immunoblotting , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Donantes de Tejidos
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