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Biomedical subjects

P Ray

Publications and source records attributed to P Ray.

At least 73 records · Page 4Linked to original sources

Computer-generated recall letters for underimmunized children: how cost-effective?

OBJECTIVE: To evaluate the effectiveness and cost effectiveness of computer-generated recall letters to parents of children overdue for immunizations. METHODS: This randomized controlled trial included children of two facilities in a regional health maintenance organization. Parents of 20-month-olds who had not yet received a measles-mumps-rubella (MMR) immunization were identified via a computerized immunization tracking system. One half were mailed personalized letters that included the recommended immunization schedule and a request to call for an appointment; the other half served as a control group. Receipt of the MMR between 20 and 24 months of age was evaluated with the computerized tracking system. A telephone survey was conducted with parents whose children had not received the MMR by 24 months. Decision analysis was used to project the theoretical outcomes and costs of a recall letter policy for other populations. RESULTS: Among 20-month-old children 10% had not received the MMR; 289 families were included in the analysis. Of families who were mailed letters, 54% (82 of 153) received the MMR by 24 months of age, compared with 35% (47 of 136) of those in the control group (P = 0.001). The telephone survey was completed with 110 parents of children who still did not appear on the health plan computer as having received the MMR by 24 months. Fifteen percent said the child had received an immunization at an outside provider, and of the rest 62% said they had not been aware that an immunization was due. In the cost effectiveness analysis it was projected that recall letters would increase the immunization rate for the regional population of approximately 30000 children from 86% to 90% at a total cost of $5031 annually. The cost per additional child appropriately immunized was $4.04. In sensitivity analyses this cost effectiveness ratio varied depending on the baseline population coverage rate as well as the estimated effectiveness of recall letters. CONCLUSIONS: Computer-generated letters to recall children overdue for immunizations resulted in a higher proportion of children appropriately immunized in this setting. However, the strategy was not as cost-effective as intuition might suggest. Further studies in health maintenance organization (HMO) settings should compare the cost effectiveness of letters with other low cost strategies including automated telephone reminders.

California↗

Safety and immunogenicity of Chiron/Biocine recombinant acellular pertussis-diphtheria-tetanus vaccine in infants and toddlers.

OBJECTIVE: To evaluate the safety and immunogenicity of the recombinant acellular pertussis-diphtheria-tetanus (aPDT) vaccine (C-aPDT, Chiron/Biocine). STUDY DESIGN: This is a randomized blinded trial evaluating the safety and immunogenicity of the recombinant aPDT vaccine (C-aPDT, Chiron/Biocine) in 2000 infant recipients compared with 498 controls who received whole cell diphtheria-pertussis-tetanus (wDPT; Connaught) vaccine at 2, 4 and 6 months of age. In addition the safety and immunogenicity of the same C-aPDT vaccine were evaluated as a booster dose in a subset of the same population when given at 15 to 18 months of age and compared with licensed Lederle aPDT vaccine. RESULTS: The C-aPDT vaccine was associated with very few local or systemic reactions when compared with wDPT. In toddlers the local and systemic side effects observed were similar after either acellular vaccine. When the immunogenicity of the C-aPDT vaccine was compared with the wDPT (Connaught) in infancy, the vaccines were equivalent for anti-diphtheria response, the wDPT developed higher anti-tetanus response and the C-aPDT vaccine was significantly more immunogenic for all other antigens tested. In toddlers the C-aPDT acellular vaccine exhibited equal or improved immunogenicity for antigens tested as compared with Lederle aPDT except for a higher anti-filamentous hemagglutinin response with the Lederle aPDT vaccine. CONCLUSION: The Chiron/Biocine aPDT vaccine offers an improved safety profile as well as improved immunogenicity when compared with a licensed wDPT product.

Antibodies, Bacterial↗

Risk of hospitalization because of aseptic meningitis after measles-mumps-rubella vaccination in one- to two-year-old children: an analysis of the Vaccine Safety Datalink (VSD) Project.

OBJECTIVE: To assess the level of increased risk, if any, of hospitalizations for aseptic meningitis after Jeryl-Lynn mumps strain measles-mumps-rubella (MMR) vaccine in the Vaccine Safety Datalink population. STUDY DESIGN: A possible increased risk of aseptic meningitis 8 to 14 days after receipt of MMR was observed in a preliminary screening analysis of automated data from the Vaccine Safety Datalink (VSD) project Year 2 analysis. To further evaluate this association a retrospective 10-year matched case-control study was undertaken in the four health maintenance organizations (HMOs) in the VSD project. Cases ascertained from a broad scan of the automated data were validated against a standard case definition. Two controls matched on age, sex, HMO and HMO membership were assigned per case. RESULTS: The VSD project involves the cooperative collection of automated vaccination and medical outcome data from four large HMOs that currently have 500,000 children younger than 7 years of age under surveillance. Review of automated screening results from the first 2 years of data revealed a possible increased risk of aseptic meningitis 0 to 14 days after MMR with a relative risk of 3.61 (95% confidence interval, 1.0 to 13.1) although the total number of cases was small. Although the automated data had suggested a possible association of aseptic meningitis with MMR containing the Jeryl-Lynn strain of mumps, review of validated hospitalized cases during the observation period did not reveal evidence of an increased risk of aseptic meningitis after MMR containing the Jeryl-Lynn strain of mumps (odds ratio < 1.0 for all analyses). CONCLUSION: Although it is recognized that hospitalized cases represent a minority of the total cases of aseptic meningitis, it is reassuring that in this evaluation no increased risk of aseptic meningitis after MMR vaccine was found.

Case-Control Studies↗

MMR2 immunization at 4 to 5 years and 10 to 12 years of age: a comparison of adverse clinical events after immunization in the Vaccine Safety Datalink project. The Vaccine Safety Datalink Team.

BACKGROUND: The Advisory Committee on Immunization Practices recommends a second dose of measles, mumps, and rubella vaccine (MMR2) at age 4 to 5 years of age, whereas the American Academy of Pediatrics suggests MMR2 immunization at age 11 to 12 years of age. Because there is little information on whether the rate of adverse reactions to MMR2 immunization varies among these two age groups, we took advantage of differing immunization policies at two large HMOs to compare the frequency of clinical events after, and possibly related to, MMR2 immunization. METHODS: Information was collected on clinical events plausibly associated to MMR immunization (seizures, pyrexia, malaise/fatigue, nervous/musculoskeletal symptoms, rash, edema, induration/ecchymoses, lymphadenopathy, thrombocytopenia, aseptic meningitis, and joint pain) in two cohorts. At three facilities at Northern California Kaiser (Oakland, CA), 8514 children received MMR2 immunization at age 4 to 6 years of age; at Group Health Cooperative (Seattle, WA) 18 036 children received MMR2 immunization at age 10 to 12 years of age. To account for age-related differences in health care use, within each HMO, clinical events in a 30-day period after immunization were compared with a 30-day period before vaccination. RESULTS: Children 10 to 12 years of age were 50% more likely to have a clinical event after MMR2 immunization than in the period before immunization (odds ratio, 1.45; 95% confidence interval: 1.00,2.10). Children 4 to 6 years of age were less likely to have a visit for an event after immunization compared with the period before immunization (odds ratio, 0.64; 95% confidence interval: 0.40,1.01). CONCLUSIONS: These results suggest that the risk for clinical events after MMR2 immunizations is greater in the 10- to 12-year age group.

Adolescent↗

Iodine nutritional status of the school-age children in South Tripura, North East India.

To evaluate the iodine nutritional status, the thyroids of 3,577 school-age children of both sexes are examined clinically by palpation for goiter prevalence, 345 urine samples are analysed by dry ashing to determine the urinary iodine excretion pattern and 121 edible salt samples collected from house hold are analysed by iodometric titration to monitor the iodinatien achieved through salt from 6 representative areas of South Tripura in goiter endemic North East India. Endemic goiter is found prevalent in all the study areas though its occurrence varies from 13.95% to 30.96%, indicating that clinically mild to severe degree of iodine deficiency prevails in the region. But the pattern of median urinary iodine level of the studied population shows that there is no biochemical iodine deficiency. In 66.94% salt samples had iodine content less than the recommended level of 15 ppm. As per the classification recommended by WHO/UNICEF/ICCIDD, South Tripura falls into goiter endemic by clinical criteria and no endemicity by biochemical criteria. However, iodine deficiency disorders (IDD) continue to be prevalent in the region.

Adolescent↗

Western blot analysis of serological response in Helicobacter pylori in acid peptic diseases.

A prospective study was undertaken in 70 patients presenting with acid peptic disease with the objective of characterising the serological response to Helicobacter pylori and finding antigens specific for the serodiagnosis of H. pylori infection. H. pylori status was assessed by smear microscopy, rapid urease activity, culture and histopathology of endoscopic gastric antral biopsy specimens. Serological characterisation was carried out by using western blotting of various antigenic components of H. pylori and subsequent enzymatic detection of antibodies against them. Four reactive bands in the molecular weight range of 45-65 kDa were present in all subjects irrespective of H. pylori status. Four to six immunoreactive bands in the molecular weight range of 21-45 kDa were found only in patients with positive H. pylori status and histopathologically proven gastritis. These immunoreactive components may be valuable in specific immunodiagnosis of H. pylori infection.

Adolescent↗

Targeted expression of IL-11 in the murine airway causes lymphocytic inflammation, bronchial remodeling, and airways obstruction.

Interleukin-11 is a pleotropic cytokine produced by lung stromal cells in response to respiratory viruses, cytokines, and histamine. To further define its potential effector functions, the Clara cell 10-kD protein promoter was used to express IL-11 and the airways of the resulting transgene mice were characterized. In contrast to transgene (-) littermates, the airways of IL-11 transgene (+) animals manifest nodular peribronchiolar mononuclear cell infiltrates and impressive airways remodeling with subepithelial fibrosis. The inflammatory foci contained large numbers of B220(+) and MHC Class II(+) cells and lesser numbers of CD3(+), CD4(+), and CD8(+) cells. The fibrotic response contained increased amounts of types III and I collagen, increased numbers of alpha smooth muscle actin and desmin-containing cells and a spectrum of stromal elements including fibroblasts, myofibroblasts, and smooth muscle cells. Physiologic evaluation also demonstrated that 2-mo-old transgene (+) mice had increased airways resistance and non-specific airways hyperresponsiveness to methacholine when compared with their transgene (-) littermates. These studies demonstrate that the targeted expression of IL-11 in the mouse airway causes a B and T cell-predominant inflammatory response, airway remodeling with increased types III and I collagen, the local accumulation of fibroblasts, myofibroblasts, and myocytes, and obstructive physiologic dysregulation. IL-11 may play an important role in the inflammatory and fibrotic responses in viral and/or nonviral human airway disorders.

Airway Obstruction↗

FISH detection of chromosome 15 deletions in Prader-Willi and Angelman syndromes.

We have evaluated fluorescence in situ hybridization (FISH) analysis for the clinical laboratory detection of the 15q11-q13 deletion seen in Prader-Willi syndrome (PWS) and Angelman syndrome (AS) using probes for loci D15S11, SNRPN, D15S10, and GABRB3. In a series of 118 samples from patients referred for PWS or AS, 29 had deletions by FISH analysis. These included two brothers with a paternally transmitted deletion detectable with the probe for SNRPN only. G-banding analysis was less sensitive for deletion detection but useful in demonstrating other cytogenetic alterations in four cases. Methylation and CA-repeat analyses of 15q11-q13 were used to validate the FISH results. Clinical findings of patients with deletions were variable, ranging from newborns with hypotonia as the only presenting feature to children who were classically affected. We conclude that FISH analysis is a rapid and reliable method for detection of deletions within 15q11-q13 and whenever a deletion is found, FISH analysis of parental chromosomes should also be considered.

Angelman Syndrome↗

Clinical experience with preimplantation genetic diagnosis of cystic fibrosis (delta F508).

Preimplantation genetic diagnosis (PGD) was attempted in 12 couples in whom both parents carry the common delta F508 deletion causing cystic fibrosis (CF). In vitro fertilization (IVF) was followed by cleavage stage biopsy on days 2 and 3 and removal of one or two cells for genetic analysis by nested polymerase chain reaction (PCR) and heteroduplex formation. A total of 18 cycles resulted in 137 normally fertilized embryos, of which 115 developed to cleavage stages and 114 were successfully biopsied. Genetic analysis was successful in 83 embryos (73 per cent). With the remaining embryos, either results from two or more cells were discordant or amplification failed. In 15 cycles, one or two either normal or carrier embryos were transferred and five (33 per cent) clinical pregnancies were established. Five singletons have been born and at birth all five babies have been confirmed as homozygous for the normal allele. Our experience demonstrates that IVF and cleavage stage biopsy consistently provides sufficient embryos, diagnosed as unaffected, for transfer in this autosomal recessive disease and that pregnancy rates are comparable to those following IVF.

Adult↗

A novel 70-kDa Triton X-114-soluble antigen of Plasmodium falciparum that contains interspecies-conserved epitopes.

In order to identify novel conserved integral membrane and other membrane-associated proteins of Plasmodium falciparum, lambda gt11-P. falciparum DNA library phages were immunoscreened with convalescent-phase mouse sera and rabbit antiserum against Triton X-114-soluble proteins of P. falciparum. One recombinant phage clone, L857, reacted with both of the antibody probes. Insert DNA (857 bp long) in L857 was 69% dA+dT rich and hybridized to a fragment of 1800 bp from mung bean nuclease-digested P. falciparum genomic DNA. The cloned parasite DNA did not show notable sequence homology with any known protein gene. The L857-encoded polypeptide, p34 (M(r) 34 kDa) was expressed in bacteria, fused to glutathione S-transferase (GST). The fusion peptide, GST-p34 (M(r) 62 kDa), was recognized by immune serum against Triton X-114-soluble antigens of P. falciparum and was reactive with anti-P. falciparum, anti-Plasmodium yoelii, and anti-GST sera. Rabbit antiserum raised against the fusion peptide recognized a 70-kDa protein from lysates of P. falciparum cells and a putative homologous 100-kDa protein from lysates of P. yoelii. The rabbit serum anti-fusion peptide antibodies bound to acetone-fixed P. falciparum-infected erythrocytes and, in immunofluorescent antibody tests, produced a punctate pattern of fluorescence suggesting that the 70-kDa native protein is associated with an apical organelle of the parasite.

Amino Acid Sequence↗

Bacteriology of necrotizing infections of soft tissues.

BACKGROUND: Necrotizing infections of soft tissues (NIST) are being attributed to a large variety of organisms, besides the originally described beta-haemolytic Streptococcus. A detailed bacteriological study of these infections was thought worthwhile. METHODS: A prospective study of 55 patients with NIST was carried out. Analysis of surface swabs and debrided tissue for aerobic and anaerobic bacteria and fungal infection was performed. A detailed bacteriological profile was obtained in 50 patients. RESULTS: A total of 257 isolates (167 aerobic, 90 anaerobic) was obtained. One to nine strains of bacteria were isolated from each patient. Aerobic bacteria alone were isolated in 26 patients while the remaining patients grew both aerobic and anaerobic bacteria. Forty-two patients had at least one Gram-positive bacterium while 40 had at least one Gram-negative bacterium. Staphylococcus aureus was the organism isolated most frequently (52%), followed by Bacteroides fragilis (40%) and anaerobic cocci (38%). Group A beta-haemolytic streptococci were isolated in 16%. Blood cultures were positive in only eight patients. Fungal cultures were positive in six patients. Aspergillus fumigatus was the commonest pathogen. CONCLUSIONS: Necrotizing infections of soft tissues are polymicrobial and no single bacterium is associated with a specific clinical entity. Importance should be placed on early recognition and treatment of the disease rather than on isolation of bacteria.

Adolescent↗

Would better adherence to guidelines improve childhood immunization rates?

OBJECTIVE: To evaluate the contribution of three provider practices to underimmunization of children with financial coverage for vaccines. DESIGN: Retrospective cohort study of children in a large health maintenance organization, based on computerized databases and chart review. SETTING: Large health maintenance organization in northern California. PATIENTS: The population included 24,268 children who had at least one immunization recorded in the health plan tracking system and had continuous health plan membership between 15 and 24 months of age in 1992 through 1993. The study group (N = 4691) were those who had missed one or more of the immunizations due during their second year. RESULTS: Most (57%) of the underimmunized children had made at least one clinic visit between 15 and 24 months of age. Among those underimmunized children who made well care visits, 90% had been partially immunized at the visit but had not been simultaneously given all vaccines for which they were eligible. When a provider did not give all possible vaccines simultaneously, there was a 9% chance that the child would go on to miss the remaining immunization. Simultaneous administration alone would have achieved full second year coverage of 30% of the underimmunized children in this population. Most underimmunized children (53%), including 35% of those children who had not made any well care visits, had made urgent visits between 15 and 24 months of age. Chart review of randomly sampled patients showed no obstacle or contraindication to immunization at 79% of urgent visits and at 71% of well care visits at which vaccines were withheld. A policy to use weekday urgent visits to promote immunization could potentially reach 27% of the underimmunized children. CONCLUSIONS: Provider practices play an important role in underimmunization of children who have insurance coverage for vaccines. Of the three guidelines evaluated, simultaneous administration of all possible vaccines has the greatest potential effectiveness to improve coverage rates in this population. Other guidelines, such as immunizing at urgent visits, are potentially effective but their costs and logistics need further study.

California↗

Potential role of platelets and coagulation factors in the metastasis of prostatic cancer.

One of the common surgical procedures used in the management of prostate cancer is transurethral resection of the prostate in which the possibility of the escape of tumor cells and their encounter with the hemostatic system is reported to contribute to the threat of hematogenous dissemination. We are reporting about the role of the hemostatic system involving the platelets and coagulation factors in the dissemination process in a tumor model carrying Dunning's R3327 AT3 adenocarcinoma of the prostate whose metastatic behavior is similar to that of human prostatic cancer. Our data revealed that the number of circulating platelets dropped and their aggregation activity increased in tumor-bearing rats as compared to controls. Normal platelets when treated with tumor effusions and reacted with the exogenous aggregating agent collagen exhibited a significant increase in the aggregating activity suggesting that the tumor and its microenvironment were capable of activating the hemostatic system. Out of eight coagulation factors measured only factors XI and XII were significantly decreased in tumor-bearing rats. The role of platelets in the metastatic process is discussed.

Adolescent↗

Improved biodistribution, tumor targeting, and reduced immunogenicity in mice with a gamma 4 variant of Campath-1H.

Radiolabeled antibodies have shown promise for the treatment of lymphoma and for solid tumor targeting. Campath-1H is a humanized monoclonal antibody that reacts with the CD52 antigen present on human lymphoid and myeloid cells. Campath-1H is a gamma1 (G1) isotype that induces lymphopenia via an Fc-mediated mechanism(s). Isotype switches were engineered, and the resulting antibodies were expressed in NS0 mouse myeloma cells and biosynthetically radiolabeled with [35S]methionine. The forms included G1, G4, and a G4 variant that contained alanine substitutions at (EU numbering) Leu-235, Gly-237, and Glu-318. All isotypes bound antigen equivalently as assessed by target cell binding in vitro. The G4 variant had a greatly reduced capacity to interact with Fc receptor by virtue of reduced binding to THP-1 human myeloid cells and by a 1000-fold increase in EC50 to intermediate antibody-dependent cellular cytotoxicity. The pharmacokinetics of the isotypes were compared in CD-1 (nu/nu) mice bearing an experimental antigen-expressing tumor. The plasma half-life and tumor uptake were increased for the G4 variant. The G4 variant showed significantly less spleen, liver, and bone uptake but similar uptake in the lung, kidney, and stomach and lower tissue-to-blood ratios. Immunogenicity was assessed after repeated monthly administrations of unlabeled antibody in BALB/c mice. A 50% reduction in the incidence of anti-globulin response was observed for the G4 variant. These properties suggest that antibodies with reduced Fc receptor interaction merit additional study as potential targeting vehicles relative to other isotypes for radioimmunotherapy or situations where diminished normal tissue binding contributes to efficacy.

Alemtuzumab↗

The potential for normal tissue dose reduction with neoadjuvant hormonal therapy in conformal treatment planning for stage C prostate cancer.

PURPOSE: Preirradiation hormonal cytoreduction of prostate cancer has been proven to reduce exposure of normal structures by decreasing the size of the target volume. Dose-volume histogram (DVH) analysis, however, does not always appear to demonstrate a strong positive benefit with the use of neoadjuvant hormone therapy. This study analyzes various other factors influencing dose to normal organs, which may determine the success or failure of neoadjuvant hormonal therapy in achieving its goals. METHODS AND MATERIALS: Patients with bulky clinical Stage C adenocarcinoma of the prostate were given 3 months of hormone treatment consisting of oral Flutamide and monthly Zoladex injections prior to irradiation. Computerized tomography (CT) scans of the pelvis were obtained both prior to and following hormonal treatment. Treatment plans were generated by three-dimensional (3D) conformal treatment planning. The change in the volume of the prostate was assessed along with the percentage of prescribed dose delivered to the rectum and bladder. Various factors such as prostate size, bladder/rectum size, and organ shape were studied. Both dose-volume histograms (DVH) and dose-surface area histograms (DSH) were used for analysis. RESULTS: Six of seven patients had reduction in the size of their prostates. The mean volumes of the prostate before and after hormonal manipulation were 129.1 +/- 32.9 standard deviation (SD) cm3 and 73.0 +/- 29.5 SD cm3, respectively (p = 0.0059). The volume of rectum receiving 80% of the prescribed dose was reduced in five of seven patients from a mean of 83.2 to 59.9 cm3 (p = 0.045). The volume of bladder receiving 80% of the prescribed dose was also reduced in five out of seven patients from a mean of 74.5 to 40.2 cm3 (p = 0.098). Correlation between the size of the prostate and volume of rectum and bladder treated was not always consistent: greater reduction in prostate size did not necessarily result in large decreases in dose to bladder or rectum. The total size of the bladder and rectum were found to be important factors in normal tissue radiation exposure; the benefits of hormone therapy may be lost if the bladder and rectum are allowed to decrease in size. Also, the bladder may be prone to sagging into the pelvis of some patients following hormone therapy, resulting in a less optimal therapeutic ratio. CONCLUSION: Reduction in prostate size by neoadjuvant hormonal manipulation does decrease the amount of normal tissue irradiated in most patients. However, the correlation between the reduction in prostate size and amount of rectum or bladder treated is not linear if other variables are not controlled. Factors such as the shape of the organs, as well as the distensible nature of the bladder and rectum, play major roles in dose to normal tissues. These facts may mask the benefits of cytoreduction and could be obstacles in realizing consistent benefits from preirradiation hormonal treatment in the clinical setting if they are ignored.

Adenocarcinoma↗

Activation of the interleukin-5 promoter by cAMP in murine EL-4 cells requires the GATA-3 and CLE0 elements.

Interleukin-5 (IL-5) plays a central role in the growth and differentiation of eosinophils and contributes to several disease states including asthma. Accumulating evidence suggests a role for cAMP as an immunomodulator; agents that increase intracellular cAMP levels have been shown to inhibit production of cytokines predominantly produced by T helper (Th) 1 cells such as IL-2 and interferon gamma (IFN-gamma). In contrast, the production of IL-5, predominantly produced by Th2 cells, is actually enhanced by these agents. In this report, we have performed transient transfection experiments with IL-5 promoter-reporter gene constructs, DNase I footprinting assays, and electrophoretic mobility shift assays to investigate the key regulatory regions necessary for activation of the IL-5 promoter by dibutyryl cAMP and phorbol esters in the mouse thymoma line EL-4. Taken together, our data demonstrate the critical importance of two sequences within the IL-5 5'-flanking region for activation by these agents in EL-4 cells: one, a highly conserved 15-base pair element present in genes expressed by Th2 cells, called the conserved lymphokine element 0 (CLE0; located between -53 and -39 in the IL-5 promoter), and the other, two overlapping binding sites for the transcription factor GATA-3 (but not GATA-4) between -70 and -59. Taken together, our data suggest that activation via the unique sequence combination GATA/CLE0 results in selective expression of the IL-5 gene in response to elevated levels of intracellular cAMP.

Animals↗

Interleukin 4-inducible phosphorylation of HMG-I(Y) is inhibited by rapamycin.

The non-histone chromosomal protein HMG-I(Y) participates in repression of transcription directed by a promoter which confers interleukin 4 (IL-4)-inducible activation in transfected B cell lines. Metabolic labeling, phosphoamino acid analyses, and in vitro phosphorylation studies demonstrate that IL-4 induces serine phosphorylation of HMG-I(Y) in B lymphocytes. Phosphopeptide mapping shows that the predominant site of phosphorylation contains a casein kinase II consensus motif. The immunosuppressive agent rapamycin has been shown preferentially to inhibit IgE production by IL-4-treated human B cells. It is shown here that rapamycin inhibits both activation of the human germ line epsilon promoter by IL-4 and IL-4-inducible phosphorylation of HMG-I(Y). These findings demonstrate a rapamycin-sensitive pathway that transduces signals from the IL-4 receptor to nuclear factors that regulate inducible transcription. The affinity of normal nuclear HMG-I(Y) for DNA is increased by dephosphorylation in vitro, whereas in vitro kinase reactions using casein kinase II decrease recombinant HMG-I(Y) binding to DNA. These data further suggest a novel mechanism in which phosphorylation triggered by IL-4 or other cytokines could regulate the effects of HMG-I(Y) on gene transcription.

Amino Acid Sequence↗

Infection of baboons with simian/human immunodeficiency viruses.

Baboons were evaluated for their utility to serve as a model for testing envelope-based vaccines against human immunodeficiency virus type 1 (HIV-1). The ability of HIV-1 strains IIIB, RF, and SF2 to infect baboons was compared with that of simian/human immunodeficiency virus (SHIV) recombinant viruses comprised of either HXB2 or SF2 env, tat, rev, and vpu genes inserted into the SIVmac239 backbone. Both SHIV recombinants replicated in baboon PBMC in vitro, while no evidence of replication was noted for HIV-1 strains (MN, IIIB, SF2). Infection of baboons in vivo correlated with the restriction of infection in vitro. Virus was recovered by cocultivation methods early after SHIV (HXBc2) infection of two baboons with seroconversion profiles that parallel those observed in simian immunodeficiency virus (SIV)mac-infected rhesus monkeys. One of two baboons inoculated with SHIV(SF2) also seroconverted within 4 weeks; however, the kinetics of infection in a second animal appeared much later, with seroconversion to gp120 not evident until 20 weeks and no virus recovery during 32 weeks following infection. Viral DNA was detected in the lymph nodes of the SHIV-inoculated animals by nested polymerase chain reaction (PCR) amplification. Histopathologic changes were evident in lymph nodes, yet no overt clinical disease was observed. When HIV-1 strains (IIIB, RF, and SF2) were inoculated into baboons, virus was not recovered and no seroconversion to the major HIV-1 antigens was observed. However, viral DNA from the lymph nodes of four animals inoculated with HIV-1 strains could be detected by nested PCR, indicating a persistent but diminutive infection of HIV-1. The baboon thus represents a new animal model for testing HIV-1 envelope-based vaccines including the evaluation of new immunogens, dosages, routes, and adjuvants that act in eliciting protective responses.

Animals↗