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1.
Ann Epidemiol ; 11(7): 512-8, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11557184

ABSTRACT

PURPOSE: Kaposi's sarcoma-associated herpesvirus (KSHV), a gammaherpesvirus recently discovered among AIDS patients with Kaposi's sarcoma, is a potential candidate for screening in blood and plasma donors. While a number of studies have assessed KSHV infection among U.S. blood donors, larger-scale population-based studies would be necessary to develop more refined estimates of the magnitude and variation of KSHV infection across different geographic regions of the U.S. blood supply. The goal of the present study, therefore, was to determine the seroprevalence of KSHV infection and to assess demographic correlates of KSHV infection among south Texas blood donors. METHODS: KSHV infection was determined using specific serologic assays that measure antibodies to KSHV latent and lytic antigens. RESULTS: The overall seroprevalence of KSHV in Texas blood donors (15.0%) is substantially higher than previously reported among blood donor and general population samples in the United States. This high rate of KSHV infection persisted across most of the sociodemographic subgroups under study but was particularly elevated among participants with less than a high school education. The infection rate also increased linearly with age. CONCLUSIONS: The elevated infection rate reported in the present study suggests that screening methods to detect KSHV infection in blood donors should be considered. In view of the etiologic role of KSHV for several malignancies, it would be important for future studies to directly assess the risk of KSHV transmission via blood transfusion.


Subject(s)
Blood Donors/statistics & numerical data , Herpesviridae Infections/epidemiology , Herpesvirus 8, Human , Adolescent , Adult , Female , Humans , Logistic Models , Male , Middle Aged , Seroepidemiologic Studies , Texas/epidemiology
2.
Bone Marrow Transplant ; 27(7): 761-5, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11360119

ABSTRACT

Epstein-Barr virus-associated post-transplant lymphoproliferative disorder (PTLD) has been well described as a complication following allogeneic stem cell transplantation but has only recently been reported following umbilical cord blood (UCB) transplant. We report the case of a child transplanted with unrelated mismatched UCB for juvenile chronic myelogenous leukemia (JCML) who developed EBV-associated PTLD, which was confirmed pathologically, 139 days following stem cell infusion. There was no clinical response to reduction of immune suppression, high-dose acyclovir, or alpha interferon. The patient died 160 days after transplantation. EBV was detected by polymerase chain reaction in the cord blood unit used for transplantation. This case demonstrates that EBV-associated PTLD can occur following mismatched unrelated UCB transplant and may be related to transmission of EBV infection by donor lymphocytes.


Subject(s)
Epstein-Barr Virus Infections/transmission , Fetal Blood/cytology , Fetal Blood/virology , Hematopoietic Stem Cell Transplantation/adverse effects , Lymphoproliferative Disorders/virology , B-Lymphocytes/pathology , Blood Donors , Child, Preschool , DNA, Viral/blood , Fatal Outcome , Herpesvirus 4, Human/genetics , Histocompatibility , Histocompatibility Testing , Humans , Lymphoproliferative Disorders/etiology , Lymphoproliferative Disorders/immunology , Male
3.
Arch Pathol Lab Med ; 125(3): 361-3, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11231484

ABSTRACT

CONTEXT: The etiology of idiopathic hypertrophic pyloric stenosis (IHPS) is unknown. Epstein-Barr virus (EBV) infects smooth muscle cells and is associated with leiomyomas and leiomyosarcomas of immunocompromised persons, including persons with the acquired immunodeficiency syndrome. OBJECTIVE: To determine whether EBV is causally associated with IHPS. DESIGN: Biopsy samples of the pylorus were obtained from 10 infants with projectile vomiting and pyloric hypertrophy on ultrasound, with confirmation of hypertrophy at the time of pyloromyotomy. The presence of EBV infection was tested by in situ hybridization for EBV-encoded RNA 1 (EBER1) in smooth muscle cells of IHPS. SETTING: Biopsy specimens were obtained from children treated for IHPS at a tertiary referral hospital and were tested in a clinical molecular diagnostics laboratory. RESULTS: All of the 10 smooth muscle biopsies were negative for EBER1. Cellular U6 RNA was detected in all smooth muscle samples, confirming that the RNA in the specimens was intact and capable of detection by in situ hybridization. CONCLUSIONS: The absence of EBER1 in 10 cases of clinically diagnosed and histopathologically confirmed cases of IHPS effectively excludes EBV infection of smooth muscle cells as a causal factor in the pathogenesis of IHPS.


Subject(s)
Epstein-Barr Virus Infections/virology , Herpesvirus 4, Human/isolation & purification , Hypertrophy/pathology , Muscle, Smooth/virology , Pyloric Stenosis/virology , Biopsy , Epstein-Barr Virus Infections/diagnostic imaging , Epstein-Barr Virus Infections/pathology , Female , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/pathogenicity , Humans , In Situ Hybridization , Infant , Infant, Newborn , Male , Pyloric Stenosis/diagnostic imaging , Pyloric Stenosis/pathology , RNA, Viral/analysis , Ultrasonography
5.
J Infect Dis ; 183(1): 125-9, 2001 Jan 01.
Article in English | MEDLINE | ID: mdl-11106539

ABSTRACT

Genotypes of Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) from patients with KS in South Texas were examined. Open-reading frame (ORF)-K1 and ORF-K15 DNA segments from 16 KSHV isolates were amplified by polymerase chain reaction, and KSHV subtypes were assigned on the basis of sequence variations. K1 genotyping showed that 75% exhibited C subtype and 25% exhibited A subtype. K15 genotyping showed that 56% exhibited M form, of which 89% exhibited C3 K1 subtype and 44% exhibited P form. A unique isolate was found and was classified as C6 clade. All of the M KSHV isolates had been obtained from human immunodeficiency virus-negative classic KS patients >50 years of age, of whom 78% were Hispanic. Conversely, all KS patients with AIDS were <36 years of age and exhibited P form KSHV. These findings indicate that C3/M KSHV genotypes are more prevalent in South Texas (50%) than in other US regions (3%) and that M form KSHV likely existed in this region long before the AIDS epidemic.


Subject(s)
Herpesviridae Infections/virology , Herpesvirus 8, Human/genetics , Sarcoma, Kaposi/virology , Adult , Aged , Aged, 80 and over , Female , Genotype , HIV Seronegativity , HIV Seropositivity , Herpesviridae Infections/epidemiology , Herpesvirus 8, Human/classification , Humans , Male , Middle Aged , Open Reading Frames , Phylogeny , Prevalence , Texas/epidemiology
6.
Clin Infect Dis ; 31(6): 1476-81, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11096015

ABSTRACT

Although the prevalence of human immunodeficiency virus (HIV) infection among prison inmates is reported to be high, little is known about anti-HIV treatment patterns in correctional institutions. The present study assessed antiretroviral prescribing patterns for 2360 Texas Department of Criminal Justice (TDCJ) inmates infected with HIV. In 1998, 66.8% of all TDCJ inmates infected with HIV who had CD4 lymphocyte counts < 500 cells/mm(3) were treated with highly active antiretroviral therapy (HAART). However, no substantial differences in the use of HAART were exhibited according to the sociodemographic factors under study. While the majority of inmates receiving HAART in 1998 were prescribed a combination of 2 nucleoside reverse transcriptase inhibitors (NRTIs) and 1 protease inhibitor, 11.2% were prescribed a combination of 2 NRTIs and 1 non-NRTI. In view of the elevated rate of HIV infection in correctional settings, it will be important to continue to document the pharmacotherapy patterns among prison inmates, both during and following incarceration.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Practice Patterns, Physicians' , Prisoners , Reverse Transcriptase Inhibitors/therapeutic use , Adolescent , Adult , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Prisons , Texas
7.
Ann Epidemiol ; 10(7): 470, 2000 Oct 01.
Article in English | MEDLINE | ID: mdl-11018401

ABSTRACT

PURPOSE: Kaposi's sarcoma-associated herpesvirus (KSHV, or human herpesvirus 8) is etiologically associated with Kaposi's sarcoma (KS) and primary effusion lymphoma (PEL). Although previous studies have assessed the geographic distribution of KSHV genotypes, the molecular epidemiology of KSHV remains largely unknown. The purpose of the present study was to examine the genotypes of KSHV isolates from KS patients in South Texas.METHODS: Eighteen KSHV isolates from 16 KS and 1 PEL patients in South Texas were collected between 1996 and 1998 and analyzed for KSHV subtypes by PCR sequencing of ORFK1 gene and KS330 fragment, and by PCR of ORFK15 gene. DNA sequences were aligned with known sequences and KSHV subtypes were assigned based on sequence variations.RESULTS: Of 18 KSHV isolates, 13 exhibited C subtype, and 5 exhibited A subtype in ORF K1 gene. ORF K15 genotyping showed that 10 of the isolates exhibited M form, of which 9 had C3 subtype. A unique C subtype isolate was found and classified as C6 clade. All of the M form KSHV isolates were found among KS patients over 50 years of age. Conversely, all KS patients under 40 years of age had only the P form KSHV isolates.CONCLUSIONS: In South Texas there is a distinct distribution of C3/M KSHV isolates, which are rarely found in other US regions (1 of 29). The C3/M KSHV genotype is more prevalent in HIV-negative elderly KS patients while the P-form of KSHV is more common among many young AIDS-KS patients.

8.
Ann Epidemiol ; 10(7): 474, 2000 Oct 01.
Article in English | MEDLINE | ID: mdl-11018410

ABSTRACT

PURPOSE: Although prison inmates are reported to exhibit substantially elevated rates of HIV infection, little is known about HIV treatment patterns, particularly pharmacotherapy, in correctional institutions. The purpose of the present study, therefore, was to describe antiretroviral prescribing patterns in one of the nation's largest prison populations.METHODS: The study population consisted of all known (n = 2,360) HIV-infected inmates incarcerated in the Texas prison system in 1998. Information on medical conditions, sociodemographic factors, and pharmacotherapy was obtained from an institution-wide medical information system. Inmates who received more than one type of pharmacotherapy in 1998 were included in the appropriate number of categories.RESULTS: In 1998, 66.8 percent (95% CI = 64.0-69.4) of all HIV-infected inmates with CD4 counts below 500 were treated with highly active antiretroviral therapy (HAART); and 31.1 percent (95% CI = 29.3-33.0) were given no antiretroviral therapy. Logistic regression results showed that HAART treatment decreased monotonically as a function of patient CD4 count category.CONCLUSIONS: A substantial proportion of HIV-infected TDCJ inmates were placed on therapies that were not consistent with the generally recommended DHHS guidelines for their disease stage. It will be important to for future investigations to assess whether such patterns continue to exist among prison populations, and to assess the determinants of these patterns.

9.
J Allergy Clin Immunol ; 106(3): 559-66, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10984378

ABSTRACT

BACKGROUND: Peripheral blood CD4(+) and CD8(+) T cells, CD19(+)/20(+) B cells, and serum Igs are known to be altered by the progression of pediatric HIV-1 infection, but their evaluation as predictors of survival needs further definition. OBJECTIVE: To determine the natural history of these immune factors and their importance in predicting survival, we studied 298 HIV-1 vertically infected (HIV-1(+)) children over a 5-year period. METHODS: These immune factors and serum HIV-1 RNA levels were measured in two groups: (1) a birth cohort of children enrolled up to age 28 days postnatally, including 93 HIV-1(+) and 463 HIV-1 uninfected infants (HIV-1(-)), and (2) an older cohort of 205 HIV-1(+) children enrolled after the age of 28 days, who were classified as survivors or nonsurvivors. RESULTS: In the birth cohort HIV-1(+) children had significantly lower CD4(+) T-cell counts, higher CD8(+) T-cell counts, and lower CD19(+)/20(+) B-cell counts and higher IgG, IgA, and IgM levels than HIV-1(-) children. In the older cohort survivors had significantly higher CD4(+) and CD8(+) T-cell and CD19(+)/CD20(+) B-cell counts and higher IgG, lower IgA, and lower IgM levels than did nonsurvivors. In univariable analysis factors affecting survival in the older cohort were baseline CD4(+) and CD8(+) T-cell and CD19(+)/20(+) B-cell counts and IgG and HIV-1 RNA levels (all P <.05). In multivariable analysis high baseline CD4(+) T-cell count and low baseline HIV-1 RNA load remained important. CONCLUSION: The longitudinal mean profiles of CD4 and CD8 T-cell and CD19/20 B-cell counts and serum IgG levels helped to describe the natural progression of HIV-1 disease in children. However, only baseline CD4 T-cell count independently predicted survival.


Subject(s)
Antigens, CD19/blood , Antigens, CD20/blood , CD4-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/cytology , HIV Seropositivity/pathology , Immunoglobulins/blood , B-Lymphocyte Subsets/pathology , Child , Child, Preschool , Cohort Studies , Female , HIV Seropositivity/mortality , HIV-1/genetics , Humans , Infant , Infant, Newborn , Lymphocyte Subsets/immunology , Male , Prospective Studies , RNA, Viral , Survival Rate , Viral Load
10.
Am J Hematol ; 64(4): 237-41, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10911374

ABSTRACT

The etiology of Langerhans cell histiocytosis (LCH) is unknown. Viral causes, including human herpesvirus type 6 (HHV6), have been suggested but remain unproved. The recently discovered human herpesvirus type 8 (HHV8), the cause of Kaposi's sarcoma, infects dendritic cells in the bone marrow associated with multiple myeloma. Evidence for an association of HHV8 infection with LCH in children was studied by two approaches: indirectly by HHV8-specific serologic assays and directly by detection of HHV8 sequences using polymerase chain reaction in affected bone marrow samples. Using three different assays specific for HHV8 antibodies, 3 of 10 (30%) children with LCH had detectable HHV8 antibodies, which was not different from the prevalence of 5 of 30 (17%) in healthy controls of similar age (P = 0.65). Of bone marrow samples from three additional children with LCH, all had amplifiable DNA but were negative for HHV8 sequences. These studies of a small number of patients do not demonstrate an increased prevalence of HHV8 infection in children with LCH, and they do not suggest a causal role for HHV8 in the etiology of LCH.


Subject(s)
Herpesviridae Infections/complications , Herpesvirus 8, Human/isolation & purification , Histiocytosis, Langerhans-Cell/etiology , Histiocytosis, Langerhans-Cell/virology , Child, Preschool , Female , Humans , Infant , Male , Prevalence
11.
Curr Opin Pediatr ; 12(3): 263-8, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10836164

ABSTRACT

Infectious mononucleosis caused by Epstein-Barr virus (EBV) usually resolves over a period of weeks or months without sequelae but may occasionally be complicated by a wide variety of neurologic, hematologic, hepatic, respiratory, and psychological complications. The strength of association of EBV with many of these complications remains based on scattered case reports, often using unsophisticated diagnostic tests, and the evidence for causation in many instances is unconvincing. There is little benefit of antiviral treatment of uncomplicated or complicated infectious mononucleosis. Corticosteroids may have a role in hastening resolution of some complications, especially upper airway obstruction and possibly immune-mediated anemia and thrombocytopenia, but should be used judiciously.


Subject(s)
Herpesvirus 4, Human , Infectious Mononucleosis/complications , Adrenal Cortex Hormones/therapeutic use , Antiviral Agents/therapeutic use , Child , Humans , Infectious Mononucleosis/diagnosis , Infectious Mononucleosis/drug therapy
13.
Br J Haematol ; 109(2): 413-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10848833

ABSTRACT

Kaposi's sarcoma-associated herpesvirus (KSHV, also known as HHV-8) has been found in patients with multiple myeloma (MM) and postulated to be aetiologically associated with the development of this common plasma cell malignancy. A murine model of MM was previously established in which intravenous transfer of 5T myeloma cells into C57BL/KaLwRij mice resulted in characteristic features of human MM. In the present study, we sought to identify herpesvirus DNA sequences in this murine model of MM through polymerase chain reaction (PCR) analysis using primers specific for KSHV, murine herpesvirus 68 (MHV68) and murine cytomegalovirus (MCMV) as well as consensus primers designed from the highly conserved DNA polymerase genes of the Herpesviridae family. None of the DNA samples from whole bone marrow (n = 6) or dendritic cells enriched by long-term culture (n = 8) of 5T myeloma-bearing mice as well as the 5T myeloma cell lines (n = 3) maintained in long-term culture yielded specific amplification products in any of the PCR assays. Two KSHV-specific serological assays measuring antibodies to KSHV latent and lytic antigens also failed to detect the presence of anti-KSHV antibodies in mice that developed MM. These results suggest that the development of 5T murine MM is unlikely to be involved with KSHV or a KSHV-like murine herpesvirus.


Subject(s)
DNA, Viral/analysis , Herpesvirus 8, Human/genetics , Multiple Myeloma/virology , Animals , Antibodies, Viral/analysis , Bone Marrow Cells/virology , Dendritic Cells/virology , Disease Models, Animal , Herpesvirus 8, Human/immunology , Humans , Mice , Mice, Inbred C57BL , Polymerase Chain Reaction/methods , Tumor Cells, Cultured
14.
J Infect Dis ; 181(4): 1462-6, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10762578

ABSTRACT

The epidemiology of herpesvirus papio, a lymphocryptovirus similar to Epstein-Barr virus (EBV), was studied in a captive colony of >1900 baboons. Herpesvirus papio IgG antibody titers were measured by IFA. In total, 438 specimens from 296 baboons were assessed, including 116 serial specimens from 52 juveniles and 6 infants studied monthly for 1 year following birth and at age 18 months. Maternally derived antibody reached a nadir at 4 months of age. About 75% of animals at 12 months of age and >95% of animals after age 24 months demonstrated serologic evidence of herpesvirus papio infection. After age 3 years, the geometric mean titer was 1:60-75. The epidemiology of herpesvirus papio infection in baboons closely parallels that of EBV infection in humans. An animal model of lymphocryptovirus infection will facilitate investigations of human lymphocryptovirus biology.


Subject(s)
Epstein-Barr Virus Infections/epidemiology , Herpesviridae Infections/veterinary , Monkey Diseases/epidemiology , Animals , Antibodies, Viral/biosynthesis , Disease Transmission, Infectious , Epstein-Barr Virus Infections/transmission , Female , Herpesviridae Infections/epidemiology , Herpesviridae Infections/transmission , Humans , Infectious Disease Transmission, Vertical , Male , Monkey Diseases/transmission , Papio , Seroepidemiologic Studies , Social Behavior
16.
J Acquir Immune Defic Syndr ; 23(2): 152-9, 2000 Feb 01.
Article in English | MEDLINE | ID: mdl-10737430

ABSTRACT

PURPOSE: To characterize AIDS-associated lymphoid malignancies in children. PATIENTS AND METHODS: We studied lymphomas and B-cell leukemias from 25 children with AIDS for immunoglobulin heavy chain gene clonality, c-myc oncogene abnormalities, and presence of HIV and Epstein-Barr virus. RESULTS: Monoclonal immunoglobulin gene rearrangements were identified in 22 of 23 cases tested, the single exception being one of mucosa-associated lymphoid tissue. Immunoglobulin gene/c-myc translocations were found in 3 of 4 cases of B (surface immunoglobulin-positive)-acute lymphoblastic leukemia, 8 of 11 small noncleaved cell lymphomas, and 1 of 5 large cell lymphomas. Mutations of c-myc were found in 2 of 13 small noncleaved cell lymphomas, 1 of 2 Epstein-Barr virus-positive mucosa-associated lymphoid tissue neoplasms, and 1 of 4 Epstein-Barr virus-negative B-acute lymphoblastic leukemia. Six small noncleaved cell lymphomas, both mucosa-associated lymphoid tissue neoplasms and one of large cell lymphoma had high levels of Epstein-Barr virus in tumor tissue. Hodgkin's disease tissue and B-acute lymphoblastic leukemia tumors were negative for EBV. Proviral HIV-1 was not detected in any tumor. CONCLUSIONS: AIDS-associated lymphoid malignancies in children appear to have a different distribution of histologic subtypes than adult HIV-infected individuals, fewer large cell lymphomas occur in children. The small noncleaved cell lymphomas exhibit a lower frequency as well as different locations of c-myc mutations than AIDS-associated small noncleaved cell lymphomas in adults.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , Leukemia, B-Cell/complications , Lymphoma, AIDS-Related/complications , Acquired Immunodeficiency Syndrome/genetics , Adult , Child , Electrophoresis, Polyacrylamide Gel , Female , Genes, Immunoglobulin , Genes, myc , HIV/isolation & purification , Herpesvirus 4, Human/isolation & purification , Humans , Lymphoma, B-Cell, Marginal Zone/genetics , Male , Polymorphism, Single-Stranded Conformational
17.
Ann N Y Acad Sci ; 918: 298-312, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11144332

ABSTRACT

Peripheral blood CD4+ and CD8+ T cells, CD19+/20+ B cells, and serum immunoglobulins (Igs) have been implicated as survival factors for pediatric HIV-1 infection. To determine which of these immune factors might be important in predicting survival, we studied HIV-1 vertically infected (HIV-1+) children over a 5-year period. Peripheral blood lymphocytes and Igs were measured in 298 HIV-1+ children, who were classified as survivors or nonsurvivors, and in 463 HIV-1 vertically exposed and noninfected (HIV-1-) children. Measurements of other possible survival factors were included in this study: albumin, hemoglobin, lactic dehydrogenase (LDH), and HIV-1 RNA levels. Survivors had significantly higher CD4+ T-cell, CD8+ T-cell, and CD19+/CD20+ B-cell counts and serum IgG levels, but lower serum IgA and IgM levels than nonsurvivors. Serum albumin and blood hemoglobin levels were higher, but serum LDH and HIV-1 RNA levels were lower in the survivors compared to nonsurvivors. In univariable analysis, factors affecting survival were baseline CD4+ T-cell and CD8+ T-cell counts, IgG, albumin, hemoglobin, LDH, and HIV-1 RNA (all p < 0.001). In multivariable analysis, high baseline CD4+ T-cell count, IgG and albumin levels, and low baseline HIV-1 RNA load remained important factors for survival. Serum IgG level has been identified as an immune factor that independently predicts survival, in addition to the already established CD4+ T-cell count. The HIV-1 RNA and serum albumin levels also predicted survival.


Subject(s)
HIV Infections/immunology , HIV Infections/mortality , Lymphocyte Count , Pregnancy Complications, Infectious , Acquired Immunodeficiency Syndrome/immunology , Acquired Immunodeficiency Syndrome/mortality , Acquired Immunodeficiency Syndrome/transmission , CD4 Lymphocyte Count , CD8-Positive T-Lymphocytes/immunology , Cohort Studies , Female , Follow-Up Studies , HIV Infections/transmission , HIV-1/isolation & purification , Humans , Immunoglobulin A/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Infant, Newborn , Infectious Disease Transmission, Vertical , Male , Pregnancy , RNA, Viral/blood , Racial Groups , Survival Rate , Time Factors , United States
18.
Am J Trop Med Hyg ; 62(5): 656-61, 2000 May.
Article in English | MEDLINE | ID: mdl-11289680

ABSTRACT

We examined the epidemiology of Cryptosporidium parvum in children aged 6 months to 13 years living in 1) colonias along the border (n = 105), 2) a clinic in an urban border community (n = 65), and 3) clinics in a large urban nonborder area (n = 109). Serum IgG and IgA anticryptosporidial antibodies were measured by enzyme-linked immunosorbent assay (ELISA). Overall, 70.2% (196/279) of subjects had detectable C. parvum antibodies. Prevalence rates were higher (93/105 [89%]) in the colonias and urban border community (53/65 [82%]) compared to the urban nonborder community (50/109 [46%]). Within colonias, independent risk factors for C. parvum infection included consumption of municipal water instead of bottled water, older age, and lower household income. Children living along the Texas-Mexico border have a higher rate of infection with C. parvum compared to children living in a large nonborder urban area. Within colonias, C. parvum infection was associated with source of water supply, age, and socioeconomic status.


Subject(s)
Antibodies, Protozoan/blood , Cryptosporidiosis/epidemiology , Cryptosporidium parvum/immunology , Adolescent , Animals , Child , Child, Preschool , Female , Humans , Infant , Male , Mexico/epidemiology , Prevalence , Risk Factors , Rural Population , Surveys and Questionnaires , Texas/epidemiology , Urban Population
19.
J Pharmacol Toxicol Methods ; 44(3): 527-32, 2000.
Article in English | MEDLINE | ID: mdl-11395331

ABSTRACT

The increased risk for cancers of the oral cavity from smokeless tobacco use may reflect the interaction of tobacco with genetic factors, such as oncogenes, and other exogenous factors, such as viruses. An in vitro system was developed based on expression of the chloramphenicol acetyltransferase (CAT) reporter gene to study interactions of chemical treatments with viral enhancer/promoters in early passage cell cultures of oral cavity-derived epithelial cells. Expression of CAT in transfected cells was significantly greater with CAT under the control of the cytomegalovirus immediate early enhancer/promoter (pCEP4/CAT) compared to the Rous sarcoma virus long terminal repeat enhancer/promoter (pRSV-cat) and the simian virus 40 (SV40) early promoter (pSV2-cat). No CAT expression was detected using corresponding control plasmids without the CAT reporter gene. Using this system, smokeless tobacco extracts prepared from either dry snuff or moist snuff delayed maximum CAT expression from Day 4 to Day 5, with sustained, significantly increased CAT expression at 12 days compared to the declining CAT expression observed in untreated control cells. Smokeless tobacco extracts can modulate intracellular gene expression. This system provides an in vitro model to test specificity of toxic agents on enhancer/promoter activity and the interaction on exogenous gene expression.


Subject(s)
Enhancer Elements, Genetic/drug effects , Gene Expression Regulation, Viral , Genes, Viral , Gingiva/drug effects , Plants, Toxic , Tobacco, Smokeless/toxicity , Avian Sarcoma Viruses/genetics , Cells, Cultured , Chloramphenicol O-Acetyltransferase/genetics , Chloramphenicol O-Acetyltransferase/metabolism , Cytomegalovirus/genetics , Enzyme-Linked Immunosorbent Assay , Epithelial Cells/drug effects , Epithelial Cells/enzymology , Epithelial Cells/virology , Gingiva/cytology , Gingiva/enzymology , Humans , Immunoenzyme Techniques , Plant Extracts/toxicity , Simian virus 40/genetics , Transfection
20.
J Infect Dis ; 180(5): 1466-76, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10515805

ABSTRACT

Molecular polymorphism was found in Kaposi's sarcoma-associated herpesvirus (KSHV) latent nuclear antigen (LNA), mapped to the internal repeat domain of the encoding orf73 gene, and used to develop a novel genotyping technique, KSHV LNA genotyping (KVNAtyping). KVNAtype was stable during latent and lytic viral replication in cell culture and in humans. Diverse KVNAtypes were identified in 43 specimens: 6 KSHV cell lines and 6 Kaposi's sarcoma (KS) and 4 primary effusion lymphoma (PEL) tumor samples from the United States, 15 KS tumor samples from Italy, and 12 KS tumor samples from Zambia. A single KVNAtype was detected in each of 41 specimens, and 2 KVNAtypes were detected in each of 2 KS specimens. Multifocal KS from 3 patients showed the same single KVNAtype at all sites in each patient. These results demonstrate a large repertoire of KSHV genotypes and suggest that the development of most KSs and PELs is associated with a single viral genotype.


Subject(s)
Antigens, Viral/genetics , Herpesvirus 8, Human/genetics , Nuclear Proteins/genetics , Polymorphism, Genetic , Sarcoma, Kaposi/virology , Cell Line , Chromosome Mapping , DNA, Viral/analysis , DNA, Viral/genetics , Genotype , Herpesvirus 8, Human/classification , Herpesvirus 8, Human/immunology , Humans , Polymerase Chain Reaction/methods
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