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Biomedical subjects

H B Jenson

Publications and source records attributed to H B Jenson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Human herpesvirus-8 (HHV-8) associated with small non-cleaved cell lymphoma in a child with AIDS.

The association of human herpesvirus-8 (HHV-8) with a small non-cleaved cell lymphoma is described in a child with the acquired immunodeficiency syndrome (AIDS) who developed a malignant pleural effusion and radiologic evidence of multiple solid tumors. HHV-8 DNA and Epstein-Barr virus DNA were identified in pleural fluid cells by polymerase chain reaction (PCR) amplification. The serum antibody titer against lytic HHV-8 proteins was 1:640; antibodies to latent HHV-8 proteins were not detected. Cytogenetic analysis of malignant cells revealed three abnormal karyotypes sharing the common finding of a t(8;14) translocation. Rearrangement of c-myc was demonstrated by PCR analysis. Oligoclonal JH immunoglobulin bands were found. Insufficient pleural fluid cells were available to permit localization of HHV-8 to malignant cells by in situ hybridization. This malignancy contrasts with HHV-8-associated lymphomas reported in adult patients with AIDS with respect to cell morphology, c-myc translocation, and oligoclonal immunoglobulin gene rearrangement. HHV-8 is associated with a wider spectrum of malignancies than recognized previously.

Adult↗
PubMed1999

The epidemiology of viral hepatitis in children in South Texas: increased prevalence of hepatitis A along the Texas-Mexico border.

An initial retrospective study of 194 children demonstrated a high prevalence of hepatitis A but not hepatitis B or C infection among children living along the Texas-Mexico border. A larger prospective study of hepatitis A was conducted with 285 children (aged 6 months to 13 years) living in 3 sociodemographically dissimilar areas of South Texas. Children living in colonías along the border had a significantly higher prevalence of hepatitis A virus infection (37%) than children living in urban border communities (17%) or in a large metropolitan area (San Antonio [6%]). Independent risk factors for hepatitis A infection included increased age, colonía residence, and history of residence in a developing country. Use of bottled water (vs. municipal or spring/well water) and years of maternal secondary education were protective. Improved sanitation or routine hepatitis A vaccination in early childhood may reduce the prevalence of hepatitis A in these areas.

Adolescent↗
PubMed1999

Molecular polymorphism of Kaposi's sarcoma-associated herpesvirus (Human herpesvirus 8) latent nuclear antigen: evidence for a large repertoire of viral genotypes and dual infection with different viral genotypes.

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.

Antigens, Viral↗
PubMed1999

A World Wide Web selected bibliography for pediatric infectious diseases.

A pediatric infectious diseases bibliography of selected medical reference citations has been developed and placed on the World Wide Web (WWW) at http://www.pedid.uthscsa.edu. A regularly updated bibliography of >2,500 selected literature citations representing general reviews and key articles has been organized under a standard outline for individual infectious diseases and related topics that cover the breadth of pediatric infectious diseases. Citations are categorized by infectious disease or clinical syndrome, and access can be achieved by the disease or by syndrome or the name of the pathogen. Abstracts, and in some cases the complete text of articles, may be viewed by use of hypertext links. The bibliography provides medical students, residents, fellows, and clinicians with a constantly available resource of current literature citations in pediatric infectious diseases. The WWW is an emerging educational and clinical resource for the practice of clinical infectious diseases.

Bibliographies as Topic↗
PubMed1999

Kawasaki syndrome-like illness associated with infection caused by enterotoxin B-secreting Staphylococcus aureus.

Two children had symptoms and clinical signs that were characteristic of the diagnostic criteria for Kawasaki syndrome, temporally associated with Staphylococcus aureus bacteremia. One child initially had focal osteomyelitis that was evident clinically and radiographically, and radiographic evidence of multifocal osteomyelitis was noted at follow-up. The blood-borne S. aureus isolates from these two patients secreted staphylococcal enterotoxin B and were negative for toxic shock syndrome toxin. Staphylococcal and streptococcal superantigens may play a role in the pathogenesis of some cases of Kawasaki syndrome or Kawasaki syndrome-like illness.

Anti-Bacterial Agents↗
PubMed1999

Using acellular pertussis vaccines for childhood immunization. Potential benefits far outweigh potential risks.

If acellular vaccines can offer protection against pertussis that is similar to that afforded by whole-cell vaccines and do so with reduced adverse effects, why have these agents not completely replaced the whole-cell preparations? This article provides an overview of general characteristics of both types of vaccine and some concerns and issues that remain in many physicians' minds. In addition, the authors furnish a rationale and recommendations for safe and appropriate use of the newer acellular formulations.

Adolescent↗
PubMed1999

Characterization of natural Epstein-Barr virus infection and replication in smooth muscle cells from a leiomyosarcoma.

Cells from a leiomyosarcoma tumor (LMS-1) from a patient with the acquired immunodeficiency syndrome (AIDS) were explanted, cultured in vitro, and studied by phase-contrast microscopy for morphologic and growth characteristics, immunostaining for cell markers, EBER in situ hybridization and polymerase chain reaction for detection of Epstein-Barr virus (EBV), and immunostaining for expression of EBV antigens. The cells exhibited very slow growth in vitro, with unusual elliptical and spindle-shaped morphology and fragmentation of the cytoplasm into long, tapering, cytoplasmic processes. Greater than 90% of cells expressed diffuse distribution of the smooth muscle isoform of actin by immunoperoxidase staining. Approximately 25% of cells expressed very bright fluorescence by immunostaining of the smooth muscle isoforms of calponin and actin. The majority of cells demonstrated a weak signal for CD21; approximately 5-10% of cells showed a strong signal that was confined to cell surfaces. The cultured cells harbored EBV, and infectious EBV continued to be detected by polymerase chain reaction and virus culture through several passages in vitro. Several EBV antigens were expressed, including latent antigen EBNA-1, immediate-early antigen BZLF1, early antigen EA-D, and late antigens, including viral capsid antigen p160, gp125, and membrane antigen gp350. Human umbilical cord lymphocytes that were transformed with virus isolated from cultured cells yielded immortalized cell lines that expressed EBV antigens similar to other EBV-transformed lymphocyte cell lines. These results confirm that EBV is capable of lytic infection of smooth muscle cells with expression of a repertoire of latent and replicative viral products and production of infectious virus. EBV infection of smooth muscle cells may contribute to the oncogenesis of leiomyosarcomas.

Acquired Immunodeficiency Syndrome↗
PubMed1998

The role of intravenous immunoglobulin for the prevention and treatment of neonatal sepsis.

The use of intravenous immunoglobulin (IVIG) for the prevention and treatment of sepsis in neonates is appealing because of the relative immunodeficiency of the neonate and the desire to improve the relatively poor outcome even with optimal antimicrobial treatment. The effectiveness of IVIG for these uses has been studied in numerous prospective as well as retrospective small and large trials that have had discordant conclusions. Meta-analysis demonstrates the marginal but significant benefit of prophylactic IVIG administered shortly after birth in preventing early onset sepsis in premature low birth weight newborns (P = .0193, two-sided). The expense of prophylactic use of IVIG administration for the relatively large premature newborn population given the minimal benefit as demonstrated by original studies and by meta-analysis is not justified. In contrast, meta-analysis of studies of IVIG for the treatment of neonates with sepsis shows a significant and unequivocal sixfold decrease in the mortality rate (P = .007, two-sided) when IVIG is administered in addition to standard therapies. The additional benefit of decreasing the risk for acute mortality indicates that the inclusion of IVIG should be considered a part of the routine therapy of neonatal sepsis.

Cross Infection↗
PubMed1998

Antibodies to Kaposi's sarcoma-associated herpesvirus (human herpesvirus 8) in patients with multiple myeloma.

Kaposi's sarcoma-associated herpesvirus (KSHV) serologic assays were used to detect specific antibodies to KSHV lytic and latent antigens in 27 patients with multiple myeloma, 27 control patients with other cancers, and 50 random blood donors. Antibodies to KSHV recombinant minor capsid antigen orf65 were found in 81% of patients with multiple myeloma, 22% of control patients with other cancers, and 6% of the blood donors. Antibodies to KSHV latent nuclear antigens were found in 52% of patients with multiple myeloma, 26% of control patients with other cancers, and 2% of the blood donors. All of the 11 patients with progressive multiple myeloma were KSHV-seropositive. Antibodies to Epstein-Barr virus nuclear antigen 1 were present in 89% of patients with multiple myeloma, 93% of control patients with other cancers, and 88% of the blood donors. These data support the possible association of KSHV infection with multiple myeloma, particularly with progressive disease.

Antibodies, Viral↗
PubMed1998

Immunofluorescence microscopy and flow cytometry characterization of chemical induction of latent Epstein-Barr virus.

The effects of chemical induction of latent Epstein-Barr virus (EBV) with 12-O-tetradecanoyl phorbol-13-acetate (TPA) and n-butyrate on cell viability and induction of latent EBV in Raji and X50-7 B lymphocytes, indicated by expression of the diffuse component of the EBV early antigen (EA-D), were measured by visual immunofluorescence microscopy (of both viable and nonviable cells) and fluorescence-activated cell sorter (FACS) flow cytometry (of viable cells only). Cell viability at 4 days decreased moderately for treated Raji cells (9 to 37%, compared to 55 to 69% for untreated cells) and markedly for X50-7 cells (1-32% compared to 35-44% in untreated cells). The highest EA-D levels in viable cells occurred in Raji cells treated with both TPA and n-butyrate and untreated X50-7 cells. TPA and n-butyrate acted synergistically to induce latent EBV, resulting in increased levels of EA-D production in Raji cells and cell death in X50-7 cells. Methodological differences including the ability to detect antigen in only viable cells by FACS flow cytometry accounted for the higher levels of EA-D observed by FACS analysis compared to the levels observed by immunofluorescence microscopy. FACS analysis may be more objective and reproducible than immunofluorescence microscopy for the detection of EBV induction and also permits viral protein expression to be distinguished in the subpopulation of viable cells.

Antigens, Viral↗
PubMed1997

The spectrum of mucosa-associated lymphoid tissue lesions in pediatric patients infected with HIV: A clinicopathologic study of six cases.

Mucosa-associated lymphoid tissue (MALT) lesions in nonimmunocompromised individuals include reactive lymphoid proliferations and both low- and high-grade lymphoid neoplasms. These lesions occur at extranodal mucosal sites, such as the gastrointestinal tract, bronchus, salivary gland, and other locations. The spectrum of MALT lesions in children with HIV infection had not been previously described. In this study, six cases that demonstrated the spectrum of MALT lesions in pediatric patients, aged 28 months to 23 years, who had HIV infection were described. Half the patients acquired the infection perinatally, and half acquired it by transfusion. Mucosal sites of involvement included the salivary gland (4 patients), bronchiolar mucosa (2 patients), and oropharyngeal mucosa (1 patient). One patient had lesions in lung and oropharynx sequentially; all others had involvement of solitary sites. The histologic diagnoses included myoepithelial sialadenitis (MESA), MESA with low-grade MALT lymphoma, typical low-grade MALT lymphoma, diffuse large cell lymphoma (DLCL), and atypical pulmonary lymphoid hyperplasia and lymphoid interstitial pneumonitis complex. The two cases of high-grade DLCL were confined to mucosal sites (tonsil and parotid); in one of these patients, a previous biopsy specimen showed a MALT lesion with low-grade features. In two cases, quantitation of the Epstein-Barr virus (EBV) genome by the polymerase chain reaction showed a very high copy number in peripheral blood mononuclear cells but a low copy number in the MALT lesion, which suggested that MALT lesions may not be directly associated with EBV infection. Two patients who had high-grade tumors (DLCL) were successfully treated with chemotherapy and radiation therapy. The remaining patients, all of whom had low-grade MALT lesions, received either corticosteroids or alpha-interferon or no specific therapy; in all patients, the lesions followed an indolent clinical course. Clinicians and pathologists should be alert to the possibility that MALT lesions, including MALT lymphomas, may be present in children who have AIDS.

Adolescent↗
PubMed1997

The baboon as a nonhuman primate model for assessing the effects of maternal immunization with Haemophilus influenzae type b polysaccharide vaccines.

These studies were performed to assess the utility of the baboon as a nonhuman primate model to evaluate vaccines for use in humans. Specifically, we examined the antibody response of baboons immunized during the third trimester of pregnancy with Haemophilus influenzae type b (Hib) polyribosylribitol phosphate (PRP) conjugate and unconjugated polysaccharide vaccines. Some of the vaccinated mothers failed to respond to a single immunization with unconjugated Hib PRP. Specific Hib PRP immunoglobulin G (IgG) but not IgM antibodies cross the baboon placenta and are detected in the offspring. Higher-titer baboon anti-Hib PRP did not express two previously defined cross-reactive human anti-Hib PRP idiotypes and was biased towards lambda light-chain expression. Spectrotype analysis indicated that baboon anti-Hib PRP was restricted in heterogeneity and oligoclonal.

Animals↗
PubMed1997

Meta-analyses of the effectiveness of intravenous immune globulin for prevention and treatment of neonatal sepsis.

OBJECTIVE: To determine the effectiveness of intravenous immune globulin (IVIG) in the prevention and treatment of neonatal sepsis. DESIGN: All published studies of IVIG for the prevention or treatment of neonatal sepsis were reviewed. Peer-reviewed, prospective, randomized trials with high merit were analyzed by two meta-analyses. The effect of prophylactic IVIG was evaluated by comparison of the numbers of cases of sepsis (bacteremia in the presence of systemic manifestations of sepsis), and of therapeutic IVIG by comparison of the numbers of deaths resulting from early-onset sepsis. RESULTS: Meta-analysis of 4933 evaluable newborns in 12 studies of IVIG prophylaxis showed a statistically significant negative association with the incidence of sepsis in premature low birth weight newborns given IVIG shortly after birth (P = .0193, two-sided). The heterogeneity across these studies precluded estimation of a common odds ratio. Meta-analysis of 110 evaluable cases of neonatal sepsis in three studies of IVIG treatment of neonatal sepsis showed a significant decrease in the mortality rate for neonates with sepsis given IVIG (P = .007, two-sided). The common odds ratio was .173 (95% confidence interval = .031 to .735). CONCLUSIONS: Using conservative and objective outcome rating criteria, the addition of IVIG to standard therapies is of minimal but demonstrable benefit in preventing sepsis when administered prophylactically to premature low birth weight newborns, and of unequivocal benefit in preventing death when administered therapeutically for early-onset neonatal sepsis. The likelihood of newborns with sepsis living past the neonatal period was improved nearly sixfold when IVIG was administered in addition to standard therapies.

Bacterial Infections↗
PubMed1997

Benign and malignant smooth muscle tumors containing Epstein-Barr virus in children with AIDS.

Smooth muscle tumors (leiomyosarcomas) are the second most prevalent malignancy of children with the acquired immunodeficiency syndrome (AIDS). We have investigated the tumors, plasma, and peripheral white blood cells of eight children with AIDS with smooth muscle tumors for evidence of tumor association with human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV). Very low levels of HIV were found in the tumors of the AIDS patients, probably resulting from blood-borne carriage of virus. These smooth muscle tumors had very high quantities of EBV in all the tumor cells by in situ hybridization, with an average of 4.5 EBV genomes per cell by quantitative polymerase chain reaction amplification. Increased amounts of EBV were found in the peripheral blood cells of two AIDS patients before the time of tumor diagnosis. EBV clonality studies demonstrated different monoclonal EBV infection of two separate colonic tumors from one patient, and dual or mixed monoclonal EBV infection in another patient. The muscle cells of leiomyomas and leiomyosarcomas of patients with AIDS demonstrated prominent staining with antibodies to the EBV receptor. The uniform distribution and striking amount of EBV in the tumor cells demonstrates that EBV is capable of infecting smooth muscle cells and that these cells support EBV replication. Clonal EBV proliferation suggests that EBV infection occurs at an early stage of tumor development. These findings indicate that EBV has a causal role in the oncogenesis of leiomyosarcomas of patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1997

New recommendations for poliovirus vaccination. Combination regimen captures best effects of available vaccines.

Unfortunately, wild poliovirus still exists in pockets around the world, so immigrants and travelers remain a potential source of infection. In addition, a few cases of vaccine-associated paralytic poliomyelitis are reported each year with use of oral vaccine alone. Fortunately, US physicians have three highly effective and acceptable options for poliomyelitis immunization. Physician and patient preferences may influence the choice, but the sequential parenteral-oral vaccine schedule is a reasoned balance of risks and benefits and should be promoted as the preferred regimen of routine vaccination of healthy children.

Adult↗