Bactericidal effect of a whey protein concentrate with anti-Helicobacter pylori activity.

AIMS: To investigate the effect of whey protein concentrate (WPC) enriched in anti-Helicobacter pylori antibodies on growth of the organism in vitro. METHODS AND RESULTS: A WPC rich in H. pylori-specific antibodies was produced by immunizing lactating cows against H. pylori and processing pooled bulk milk samples into whey powder. The antibodies bound several proteins within the bacterial homogenate and were active at pH 5. In a complement-dependent reaction, the immune WPC was highly bactericidal against four H. pylori strains tested in vitro. CONCLUSION: WPC produced with milk from H. pylori-immunized cows contains antibodies that are active at the pH of the stomach, and bactericidal against H. pylori in vitro, via the classical complement pathway. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has demonstrated the potential for use of WPC in the prevention/treatment of H. pylori infections.

Pilot study to evaluate the efficacy of hyperbaric oxygen therapy in improving the survival of reattached auricular composite grafts in the New Zealand White rabbit.

OBJECTIVE: This investigation is a prospective, randomized, blinded study seeking to evaluate the efficacy of hyperbaric oxygen (HBO) therapy in improving the survival of the reattached auricular composite graft. STUDY DESIGN: Twenty New Zealand White rabbits were randomly assigned to control (10) and treatment (10) groups in a prospective fashion. After amputation and reattachment of measured segments of each ear, the treatment group received 14 HBO treatments for 10 days. The control group received only standard postoperative care. On postoperative day 18, the surviving composite grafts were measured, recorded, and statistically analyzed. RESULTS: The mean percentage of graft survival for the control group was 0.31% (range 0%-2.5%), and the mean for the group receiving HBO was 15.94% (range 0%-38%). A median test was used to evaluate this difference, which was found to be statistically significant (P = 0057). CONCLUSION: Our study appears to indicate a possible survival benefit for the composite grafts in those rabbits that received HBO treatments. We believe that there are several significant difficulties with the rabbit as a model for this study, but we are encouraged at this point that a limited measurable benefit was observed. Further investigations with HBO appear to be warranted at this time.

An organizational climate intervention associated with increased handwashing and decreased nosocomial infections.

Handwashing practices are persistently suboptimal among healthcare professionals and are also stubbornly resistant to change. The purpose of this quasi-experimental intervention trial was to assess the impact of an intervention to change organizational culture on frequency of staff handwashing (as measured by counting devices inserted into soap dispensers on four critical care units) and nosocomial infections associated with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). All staff in one of two hospitals in the mid-Atlantic region received an intervention with multiple components designed to change organizational culture; the second hospital served as a comparison. Over a period of 8 months, 860,567 soap dispensings were recorded, with significant improvements in the study hospital after 6 months of follow-up. Rates of MRSA were not significantly different between the two hospitals, but rates of VRE were significantly reduced in the intervention hospital during implementation.

Rapid conversion of naive to effector T cell function counteracts diminished primary human newborn T cell responses.

The reduced incidence of graft versus host disease following the use of human cord blood as a source of stem cells for bone marrow reconstitution challenges our understanding of the immunocompetence of newborn T cells. Newborn CD4+ T cells express mainly the CD45RA phenotype and have been considered to respond comparably to adult CD4+ T cells exhibiting the CD45RA phenotype. We compared the in vitro kinetics of phenotypic conversion of newborn and adult CD4+CD45RA+ T cells to CD4+CD45RO+ T cells. The cytokine profile and B cell helper activity of the converted CD4+CD45RO+ T cell population were also determined. Newborn CD4+CD45RA+ T cells were converted to CD4+CD45RO+ with significantly faster time kinetics than adult CD4+CD45RA+ T cells, following either phytohaemagglutinin (PHA) or anti-CD2 activation. Freshly purified newborn naive T cells did not produce IL-2, IL-4 or interferon-gamma (IFN-gamma) following stimulation, whereas adult naive T cells secreted IL-2 and adult-derived CD4+CD45RO+ T cells secreted all three cytokines under the same stimulatory conditions. However, newborn and adult CD4+CD45RA+ T cells, following primary stimulation and maturation in vitro, acquired the ability to secrete a Th1-type cytokine profile of IL-2 and IFN-gamma after secondary stimulation. Newborn CD4+ naive T cells that acquired the CD45RO phenotype in vitro also gained B cell helper activity equivalent to that of adult in vitro matured CD4+ naive T cells. These findings suggest that newborn and adult CD4+CD45RA+ T cell subsets are differentially responsive to various stimuli. They show that newborn CD4+CD45RA+ naive T cells can transform more quickly than their adult counterparts into functionally equivalent CD4+CD45RO+ T cells, a process that may be important to counteract the immature immune environment which exists in the newborn.

Cord blood 'naive' T cells demonstrate distinct immunological properties compared with their adult counterparts.

Distinct immunological properties of naive T cells in cord blood as compared to their adult counterparts are likely to have consequences in the outcome of cord blood transplants.

Effect of several interventions on the frequency of handwashing among elementary public school children.

BACKGROUND: The purpose of this educational project was to assess the effect of several interventions on the frequency of handwashing among elementary public school children. METHODS: Participants in this project were first-graders and fourth-graders from jurisdictions within a mid-Atlantic metropolitan area. Phase I included a baseline assessment of bathroom cleanliness as well as adequacy of supplies for handwashing in each school. During phase 2, the frequency of handwashing before lunch or after bathroom use was monitored and recorded during a 2-month period. The schools were separated into four groups: a peer education group, a hand wipes and instructional poster group, a combination of the education and hand wipes/poster groups, and a (control) comparison school. RESULTS: Overall, a significant increase occurred in the proportion of handwashing frequency from preintervention to postintervention for each intervention group (wipes: 0.50 vs 0.66, p = 0.03; education only: 0.64 vs 0.72, p = 0.02; and education and wipes: 0.45 vs 0.67, p = 0.03) but not in the control group (0.42 vs 0.46, p = 0.26). When the first 3 weeks and the last 3 weeks after intervention were compared, handwashing frequency remained unchanged in the wipes only group (0.66 vs 0.66, p = 0.96), decreased in the education group (0.77 vs 0.65, p = 0.006), and increased in the education and wipes group (0.58 vs 0.75, p = 0.003), as well as in the control group (0.37 vs 0.52, p = 0.01). CONCLUSION: Education combined with accessible convenient hand hygiene may result in a sustainable increase in the frequency of handwashing among elementary school children.

Field calibration unit for ultraviolet spectroradiometers.

Horizontal standard lamps calibrate the spectral irradiance responsivity of spectroradiometers that measure solar ultraviolet irradiance. A field calibration unit and power supply developed to meet the requirements for using these standards in the field are described and their operation and associated uncertainties are detailed. Results from assessments obtained at two field instrument intercomparisons indicate that the horizontal standard, field calibration unit, and power supply operate within the design tolerances, making them suitable for performing routine calibrations in the field on most ultraviolet spectroradiometers.

Antigen-independent responsiveness to interleukin-4 demonstrates differential regulation of newborn human T cells.

The low incidence of graft-versus-host disease following clinical use of umbilical cord blood compared to adult bone marrow as a source of stem cells for bone marrow reconstitution, leads to questions concerning the level of immunocompetence of newborn T cells. The maturation and functional status of newborn CD4+ T cells, which are almost exclusively CD45RA+ naive T cells, compared with their adult phenotypic counterparts, is poorly understood. We examined the proliferative response to mitogens and cytokines of CD4/CD45RA+ T cells from adults and newborns, with and without accessory cells. Newborn CD4/CD45RA+ T cells demonstrated a distinct proliferative response profile which was determined by the number of accessory cells present in co-cultures with various stimuli. Newborn CD4/CD45RA+ T cells were particularly responsive to interleukin (IL)-4, IL-4 plus anti-CD2 monoclonal antibodies (mAb) and IL-4 plus phytohemagglutinin (PHA), whereas adult CD4/CD45RA+ T cells were unresponsive under similar conditions. The mitogenic responses of newborn and adult CD4/CD45RA+ T cells to PHA and anti-CD2 mAb, which were equivalent, were directly proportional to the number of accessory cells present, whereas the responsiveness to cytokines was inversely proportional to the number of co-cultured accessory cells. Anti-CD2 responses were much more sensitive to low numbers of accessory cells than PHA. The particular sensitivity of newborn CD4/CD45RA+ T cells to IL-4 represents an antigen-independent T cell activation response which could help promote a Th2 immune response resulting in the newborn.

Transgenic expression of PML/RARalpha impairs myelopoiesis.

The translocation found in acute promyelocytic leukemia rearranges the promyelocytic leukemia gene (PML) on chromosome 15 with the retinoic acid receptor alpha (RARalpha) on chromosome 17. This yields a fusion transcript, PML/RARalpha, a transcription factor with reported dominant negative functions in the absence of hormone. Clinical remissions induced with all-trans retinoic acid (RA) treatment in acute promyelocytic leukemia are linked to PML/RARalpha expression in leukemic cells. To evaluate the PML/RARalpha role in myelopoiesis, transgenic mice expressing PML/RARalpha were engineered. A full-length PML/RARalpha cDNA driven by the CD11b promoter was expressed in transgenic mice. Expression was confirmed in the bone marrow with a reverse transcription PCR assay. Basal total white blood cell and granulocyte counts did not appreciably differ between PML/RARalpha transgenic and control mice. Cell sorter analysis of CD11b+ bone marrow cells revealed similar CD11b+ populations in transgenic and control mice. However, in vitro clonal growth assays performed on peripheral blood from transgenic versus control mice revealed a marked reduction of myeloid progenitors, especially in those responding to granulocyte/ macrophage colony-stimulating factor. Granulocyte/macrophage colony-stimulating factor and kit ligand cotreatment did not overcome this inhibition. Impaired myelopoiesis in vivo was shown by stressing these mice with sublethal irradiation. Following irradiation, PML/RARalpha transgenic mice, as compared with controls, more rapidly depressed peripheral white blood cell and granulocyte counts. As expected, nearly all control mice (94.4%) survived irradiation, yet this irradiation was lethal to 45.8% of PML/RARalpha transgenic mice. Lethality was associated with more severe leukopenia in transgenic versus control mice. Retinoic acid treatment of irradiated PML/RARalpha mice enhanced granulocyte recovery. These data suggest that abnormal myelopoiesis due to PML/RARalpha expression is an early event in oncogenic transformation.

Patients' attitudes about gifts to physicians from pharmaceutical companies.

BACKGROUND: Little is known about patients' awareness of and attitudes about gifts to physicians from pharmaceutical companies. METHODS: During a 7-week period in summer 1994, we surveyed adults (18 years of age and older) in the waiting rooms of two family practice centers in central Missouri. Four-hundred eighty-six adults (83 percent participation rate) responded to a self-administered questionnaire that assessed awareness of and attitudes about representative gifts. RESULTS: Rates of awareness of specific gifts were 87.0 percent for free drug samples, 55.3 percent for ballpoint pens, 34.6 percent for medical books, 28.6 percent for baby formula, 22.4 percent for dinner at a restaurant, and 13.8 percent for a coffee maker. Of the 486 respondents, the following percentages were reported that "it is not all right" for physicians to accept specific gifts: dinner at a restaurant, 48.4 percent; baby formula, 44.2 percent; coffee maker, 40.7 percent; ballpoint pens, 17.5 percent; medical books, 16.9 percent; drug samples, 7.6 percent. In addition, 32.5 percent did not approve of their physicians accepting payment by a pharmaceutical company of medical conference expenses and from 28.0 percent to 43.4 percent disapproved of their physicians attending specific social events sponsored by pharmaceutical companies at a medical conference. Seventy percent of the subjects believed that gifts sometimes or frequently influence a physician's prescribing of medication; 64.0 percent believed that gifts to physicians increase the cost of medication. Beliefs that gifts influence prescribing behavior and beliefs that gifts increase medication costs were strongly associated with disapproval of each gift except for drug samples. CONCLUSIONS: Respondents distinguished between particular gifts; approval rates were high for gifts generally considered to be trivial or that have potential value to patient care; disapproval rates were relatively high for gifts that have some monetary value but have little or no benefit for patients. Opinions about gifts were related to perceptions of their effects on prescribing behavior and costs.

TB control in the hospital environment.

Tuberculosis is again on the rise in the United States. Several outbreaks of TB in hospitals have heightened interest in the development and use of mechanisms that prevent the spread of this airborne pathogen. Controlling the spread of TB to hospital patients, workers, and others can be accomplished through various administrative engineering and design controls, and infection control programs, as recommended by the Centers for Disease Control and Prevention (CDC). The hazard of TB is real, but workers, patients, and visitors can be protected by implementing programs that guard against the diseases spread in the hospital environment.

A soluble inhibitor of T lymphocyte function induced by HIV-1 infection of CD4+ T cells: characterization of a cellular protein and its relationship to p15E.

Soluble suppressor factor (SSF), first described in association with HIV-1 infection in vivo, is a molecule(s) capable of inhibiting T cell-dependent immune reactivity. Its relationship to human immunodeficiency virus (HIV) was further defined as supernatants of mononuclear cell cultures from HIV-1-seropositive carriers, CD4+ T lymphocytes infected with HIV-1 in vitro, and a T cell hybridoma incorporating CD4+ lymphocytes from an HIV-1-seropositive individual were shown to elaborate factors with similar activity profiles. These factors were recognized antigenically by certain antibodies directed against epitopes of p15E, a transmembrane protein of murine leukemia virus which shares regions of identity with proteins deduced from human endogenous retroviral envelope transcripts as well as HIV. These reagents precipitated a single-chain, nonglycosylated, nonviral protein of molecular weight 57,000 Da from SSF-producing cells. There was no cross-reactivity with antisera recognizing the IL-2R alpha-chain (CD25) or tumor necrosis factor. This molecule was present in very low levels in PHA-activated T lymphocytes and was upregulated following their infection with HIV-1. Isolation of HIV-linked SSF should permit comparisons with other virion, cellular, and serum inhibitory substances described in AIDS, and perhaps suggest therapeutic strategies.

Human immunodeficiency virus infection of monocytes: relationship to Fc-gamma receptors and antibody-dependent viral enhancement.

Antibodies that augment human immunodeficiency virus (HIV) infectivity of monocytes through Fc receptor (FcR) type III for IgG have been found in the blood of sero-positive patients and immunized chimpanzees. This study investigated the effect of acute and chronic HIV infection, as well as protein kinase C activators capable of up-regulating latent HIV, on the expression of these receptors. In addition, the frequency of this antibody-dependent enhancement (ADE) phenomenon was estimated using purified IgG from HIV-1 seropositive individuals at various clinical stages of infection. The existence of an FcR-dependent pathway for ADE of HIV-1 infection in peripheral blood monocytes and promonocytic U937 cells was confirmed in sera from a small subset of patients, and the phenomenon extended to FcR types I and II. The level of ADE activity was minimal, however, and no relationship between the presence or magnitude of the ADE phenomenon and clinical stage was uncovered. Finally, perturbations which activate a latent HIV infection were shown to concomitantly up-regulate FcR on infected and uninfected cells. This suggests a positive feedback loop linking up-regulation of latent infection, enhanced expression of low affinity HIV receptors such as FcR, and viral spread.

The baladi curative system of Cairo, Egypt.

The article explores the symbolic structure of the baladi (traditional) cultural system as revealed in everyday narratives, with a focus on baladi curative action. The everyday illness narrative provides a cultural window to the principles of fluidity and restorative balance of baladi curative practices. The body is seen as a dynamic organism through which both foreign objects and physiological entities can move. The body should be in balance, as with any humorally-influenced system, and so baladi cures aim to restore normal balance and functioning of the body. The article examines in detail a narrative on treatment of a sick child, and another on treatment of fertility problems. It traces such cultural oppositions as insider: outsider; authentic:inauthentic; home remedy:cosmopolitan medicine. In the social as well as the medical arena these themes organize social/medical judgements about correct action and explanations of events.