Pregnancy rate and reproductive hormones in humpback whale blubber: Dominant form of progesterone differs during pregnancy.

To better understand reproductive physiology of humpback whales Megaptera novaeangliae that reside in Hawai'i and Alaska, enzyme immunoassays were validated for both progesterone and testosterone in free-ranging and stranded animals (n = 185 biopsies). Concentrations were analyzed between different depths of large segments of blubber taken from skin to muscle layers of stranded female (n = 2, 1 pregnant, 1 non-pregnant) and male (n = 1) whales. Additionally, progesterone metabolites were identified between pregnant (n = 1) and non-pregnant (n = 3) females using high pressure liquid chromatography (HPLC). Progesterone concentrations were compared between juvenile (i.e., sexually immature), lactating, and pregnant females, and male whales, and pregnancy rates of sexually mature females were calculated. Based on replicate samples from ship struck animals collected at 7 depth locations, blubber containing the highest concentration of progesterone was located 1 cm below the skin for females, and the highest concentration of testosterone was in the skin layer of one male whale. HPLC of blubber samples of pregnant and non-pregnant females contain different immunoreactive progesterone metabolites, with the non-pregnant female eluate comprised of a more polar, and possibly conjugated, form of progesterone than the pregnant female. In females, concentrations of progesterone were highest in the blubber of pregnant (n = 28, 28.6 ± 6.9 ng/g), followed by lactating (n = 16, 0.9 ± 0.1 ng/g), and female juvenile (n = 5, 1.0 ± 0.2 ng/g) whales. Progesterone concentrations in male (n = 24, 0.6 ng/g ± 0.1 ng/g) tissues were the lowest all groups, and not different from lactating or juvenile females. Estimated summer season pregnancy rate among sexually mature females from the Hawai'i stock of humpback whales was 0.562 (95 % confidence interval 0.528-0.605). For lactating females, the year-round pregnancy rate was 0.243 (0.09-0.59), and varies depending on the threshold of progesterone assumed for pregnancy in the range between 3.1 and 28.5 ng/g. Our results demonstrate the synergistic value added when combining immunoreactive assays, HPLC, and long-term sighting histories to further knowledge of humpback whale reproductive physiology.

Reducing employee injuries through preventing at-risk behaviors.

This article presents the experiences of officials at two medical centers in successfully reducing and preventing employee injuries. Guidance is also provided from psychologists and employee safety experts on ways to approach the problem.

C4B deficiency is not associated with meningitis or bacteremia with encapsulated bacteria.

The two isotypes of the fourth complement component are C4A and C4B. C4B forms ester bonds more efficiently than C4A and so, in theory, is more likely than C4A to bind to polysaccharide capsules of encapsulated bacteria. Two studies have reported homozygous C4B deficiency in patients with meningitis or bacteremia caused by encapsulated organisms. In the present study the association between C4B deficiency and these disorders was evaluated in four groups: patients with bacteremia, those with meningitis, those who developed Haemophilus influenzae type b (Hib) disease after Hib polysaccharide vaccination, and patients less than 1 year old with meningitis. Healthy adults served as controls. Of the 257 patients, 2.3% had homozygous C4B deficiency compared with 3.7% of 349 controls. According to these data, there is no increase in homozygous C4B deficiency among patients with bacteremia or meningitis caused by encapsulated bacteria.

Transient lymphoblastosis and thrombocytopenia in Gianotti-Crosti syndrome.

Gianotti-Crosti Syndrome, or papular acrodermatitis of childhood, represents a characteristic rash that is irregularly associated with hepatitis B infection. The authors report papular acrodermatitis in a 10-month-old child with leukopenia, thrombocytopenia, circulating lymphoblasts, and acute anicteric hepatitis B. Physical examination revealed a densely distributed papular rash on the patient's extremities and face and neck, but not on his trunk, buttocks, palms, or soles. Laboratory investigation revealed a normal bone marrow and positive hepatitis B serology. This case reinforces the fact that hematologic findings should not dissuade the work-up of papular acrodermatitis for hepatitis B or other less commonly associated viruses.

Pediatric family care: an interdisciplinary team approach.

Providing adequate psychosocial support for hospitalized pediatric patients and their families is sometimes difficult. An interdisciplinary team can help caregivers to assess needs and develop strategies for working with difficult patients and families. This paper describes the development of a pediatric family care team that has been effective in one hospital, outlining the general steps followed in establishing the team. A review of practical considerations related to team membership, costs, and procedures is followed by a discussion of the problems encountered. A case study demonstrates how the team helped meet the psychosocial needs of one pediatric patient.

Longitudinal development of specific and functional antibody in very low birth weight premature infants.

We evaluated the formation of specific and functional antibody in preterm infants born weighing less than 1500 g (mean 1088 g) and less than 32 wk gestational age (mean 28.8 wk). Plasma IgG antibody against tetanus and diphtheria toxoids were measured by an enzyme-linked immunosorbent assay. Opsonic activity of heat-inactivated plasma was measured using radiolabeled bacteria, adult polymorphonuclear leukocytes and exogenous human complement. In the presence of complement, the strain of coagulase negative staphylococcus used was opsonized by IgG antibody, and the strain of Escherichia coli by IgM. Geometric mean plasma levels of tetanus and diphtheria IgG antibody fell from birth to 4 months chronological age, but rose significantly by 9 months (approximately 2 months after the third dose of diphtheria, tetanus, pertussis vaccine). However, at 9 months they remained lower than the respective geometric mean levels in 9-month-old term infants (tetanus: p less than 0.001; diphtheria: p = 0.02). The preterm infants' mean plasma IgG staphylococcal opsonic activity fell from birth to 2.5 months, but by 9 months was comparable to that of term infants of the same age. Mean IgM opsonic activity for E. coli was very low at birth in both preterm and term infants. It rose with chronological age, correlating with the rise in total IgM (r = 0.48, p less than 0.001) and by 9 months the mean preterm and term infants' levels of IgM opsonic activity for E. coli were comparable.(ABSTRACT TRUNCATED AT 250 WORDS)

Second episodes of Haemophilus influenzae type b disease following rifampin prophylaxis of the index patients.

Patients treated for Haemophilus influenzae type b disease frequently remain nasopharyngeal carriers of that organism and fail to develop protective concentrations of serum antibody. It has been suggested that rifampin prophylaxis of the index patient may prevent recurrence of disease by eliminating type b Haemophilus carriage. We report nine children who developed second episodes of disease 1 week or more after receiving rifampin prophylaxis. The median interval between the last dose of rifampin and admission to the hospital for the second episode was 70 days (range, 9 to 138). Analysis of biotypes and outer membrane protein polyacrylamide gel electrophoresis patterns of paired isolates from eight cases revealed that the second episodes in two of the children were caused by acquisition of new type b Haemophilus strains, whereas the second episodes in the remaining six children were caused by isolates which were indistinguishable from the respective isolates from the first episodes. Rifampin prophylaxis of the index patient may prevent some episodes of recurrent disease. However, in some patients who have received prophylaxis, second episodes can occur, probably as a result of reacquisition of the organism from contacts who did not receive rifampin or from acquisition of new type b strains.

Peripheral blood T-cell subpopulations in the very low birth weight (less than 1,500-g) infant.

The development of monoclonal antibodies to cell-surface antigens has provided method for characterizing distinct subpopulations of T-cells. In the present study we have quantified peripheral blood T-cell subpopulations in premature infants born weighing less than 1,500 g (1123 +/- 223 g) and ranging in gestational age from 25 to 32 weeks. The relative proportion of T4 cells in the very low birth weight (VLBW) infants was markedly higher at 1 week and 1 month of age (mean +/- SEM; 67.5 +/- 4.1 and 59.2 +/- 1.6) than in adult controls (47.2 +/- 1.5). The percentage of T4 cells remained elevated until 6 months of age, when it decreased to a level comparable to that in adults. In contrast, the proportion of T8 cells was significantly lower than the adult level at 1 week and 1 month of age. The T4/T8 ratio in the VLBW infants was higher at 1 week (4.3 +/- 0.5) and 1 month (3.5 +/- 0.2) than in adult controls (2.0 +/- 0.1). Thereafter, the T4/T8 ratio decreased but was still significantly higher than that in adult controls at 6 months of age (2.6 +/- 0.2). The absolute numbers of total T-cells (T3) and T8 and T4 cells were significantly higher in VLBW infants. The numbers of T8 cells were significantly lower in the first month of life than at 3-6 months of age. These alterations in the T-cell subsets in the first 6 months of life suggest that postnatal T-cell phenotypic changes in VLBW infants may parallel the T-cell ontogenetic process which occurs during the last trimester of pregnancy in full-term infants.

Hemophilus influenzae type B disease in children vaccinated with type B polysaccharide vaccine.

We studied 55 cases of invasive Hemophilus influenzae type b disease occurring in children at least three weeks after vaccination with type b polysaccharide vaccine. Their mean age at the time of immunization was 27.8 months (range, 18 to 47). Meningitis developed in 39 patients, of whom 3 died and 6 had neurologic sequelae. We investigated certain host factors that may have contributed to the failure of the vaccine. The geometric mean concentration of antibody to type b polysaccharide in convalescent-phase serum from 31 of the vaccinated patients who had hemophilus disease was significantly lower than that in serum from 25 patients of similar age with the disease who had never been vaccinated (0.59 vs. 3.46 micrograms per milliliter, P less than 0.001). However, only 3 of 46 patients in whom the vaccine failed and who were tested for hypogammaglobulinemia had this finding, and none of 33 children tested for IgG2 had low serum concentrations of this immunoglobulin subclass, which is thought to be important in the immune response to polysaccharide antigens. In addition, all but 1 of the 46 patients in whom the vaccine failed and who were tested for IgG antibody to tetanus toxoid protein, a thymic-dependent antigen, had normal values, and 19 of 20 tested for hemolytic complement activity had normal levels. In white children, the presence of the Gm immunoglobulin phenotype (1,2,3, 17; ;5,13,21) was associated with a sevenfold increase in the relative risk of vaccine failure (P less than 0.003). We conclude that vaccine failure may be related in part to genetic factors, and that most vaccinated children in whom Hemophilus influenzae disease develops have deficient antibody responses to the type b polysaccharide despite normal serum concentrations of immunoglobulin and normal antibody responses to tetanus toxoid.

Development of the immune system in very low birth weight (less than 1500 g) premature infants: concentrations of plasma immunoglobulins and patterns of infections.

Plasma immunoglobulin concentrations of premature infants of birth weight less than 1500 g were measured longitudinally from birth to 10 months chronological age. Infants were divided into two groups based on gestational age (group I: 25-28 wk; group II: 29-32 wk). In the 1st wk of life, plasma IgG levels correlated with gestational age (r = 0.5, p less than 0.001). At 3 months chronological age, the geometric mean plasma IgG levels were 60 mg/dl in group I and 104 mg/dl in group II infants. Most infants remained hypogammaglobulinemic at 6 months with seven of 11 infants in group I and 13 of 21 infants in group II having plasma IgG levels below 200 mg/dl. In the 1st wk of life, plasma IgM concentrations were 7.6 and 9.1 mg/dl in groups I and II, respectively. They rose to 41.8 and 34.7 by 8 to 10 months of life. Plasma IgA concentrations were comparable for groups I and II in the 1st wk of life (1.2 and 0.6 mg/dl, respectively), but at 1 month of age group I infants had a transient increase in IgA which was not seen in the group II infants (4.5 versus 1.9 mg/dl, respectively, p less than 0.02). This transient elevation in IgA did not correlate with type or route of feeding or amounts of transfused blood. Group I and group II infants had comparable rates of infections prior to discharge from the nursery (p = 0.27). After discharge, the 43 preterm infants followed until 10 months chronological age had a significantly higher incidence of infections than 41 term infants (p = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Use of rapidly generated results in patient management.

The usefulness of a rapid diagnostic test in patient management depends on the sensitivity of the test, the clinical consequences of false-negative or false-positive results, the ease and cost of performance, and the timely availability of results. A test that is sensitive, specific, inexpensive, and rapid is presumed to be useful clinically. However, there has been surprisingly little effort to measure the actual impact of the results on patient care. Since antigen detection for Haemophilus influenzae type b disease has been available for more than a decade, it will be used as a model to illustrate several factors that help determine the benefits, limitations, and pitfalls of antigen detection in the management of patients with serious bacterial infections. Herein we will compare the use of antigen detection in meningitis with that in other Haemophilus influenzae type b diseases. We also will review our experience with the impact of rapid diagnosis on the treatment of bacterial meningitis. Finally, other factors that influence the usefulness of antigen detection on patient care will be explored by comparing the potential consequences of laboratory error on the management of patients with Haemophilus influenzae type b infections with that of management of other kinds of infections, such as streptococcal pharyngitis, sexually transmitted diseases, and viral respiratory infections.

Clinical considerations in the diagnosis of viral respiratory infections.

Recent advances are allowing the transfer of sensitive and precise rapid viral antigen detection technology from sophisticated research laboratories to standardly equipped clinical diagnostic facilities. It is now possible to identify many viral respiratory pathogens directly from clinical specimens in less than 1 hr. Rapid antigen detection promises to be of the most value in the identification of respiratory viruses 1) for which antiviral therapy is available, 2) which can be prevented by employing isolation precautions, chemoprophylaxis, and/or immunization, 3) whose presence usually is associated with acute respiratory disease, not just asymptomatic colonization, and 4) which ordinarily are not associated with concomitant bacterial infection, and thus, whose early detection may allow withholding or withdrawing antibiotics. Based on these considerations, the relative usefulness of rapid viral antigen detection of commonly encountered respiratory pathogens will be discussed. In addition, the role of rapid viral detection in diagnosis of respiratory infections in high risk versus otherwise healthy individuals will be explored.

Functional characterization of human IgG, IgM, and IgA antibody directed to the capsule of Haemophilus influenzae type b.

Antibody to the capsular polysaccharide (CP) of Haemophilus influenzae b (Hib) is bactericidal, opsonic, and protective. Minimum protective levels of primarily IgG antibody to Hib CP, calculated from passive immunization studies, have been found to be approximately .06-.15 microgram/ml of serum. The human response to antigenic challenge with the Hib capsule, however, includes production of antibody to Hib CP of different isotypes whose function against Hib is unclear. In order to characterize the function of antibody to Hib CP of different isotypes, we purified human IgG, IgM, and IgA from the serum of an adult donor who had been previously immunized with purified Hib CP vaccine. The globulin preparations were greater than 99% isotypically pure, contained large quantities of anticapsular antibody, and differed in function against Hib. IgG antibody to Hib CP was bactericidal and opsonic for human polymorphonuclear leukocytes (PMNLs) in the presence of complement and protective in infant rats. IgM, although more bactericidal than IgG (P less than .01) and equally protective in rats, opsonized Hib poorly for PMNLs. IgA was not bactericidal or opsonic and did not prevent bacteremia and meningitis in rats challenged with Hib. We conclude that antibody directed against the capsule of Hib differs in antibacterial function depending on class. These data may be important to acurately estimate minimum protective levels of anticapsular antibody after vaccination or natural infection and may have implications for the manner in which the host clears Hib from the circulation.