Neonatal diaphragmatic hernia. An improving outlook with extracorporeal membrane oxygenation

In a 15-year period, 89 newborns were treated for congenital diaphragmatic hernia. The patients were divided into three groups, depending on postoperative therapeutic support available: group 1, ventilator therapy only; group 2, ventilator therapy plus pulmonary vasodilators (tolazoline hydrochloride); and group 3, ventilators, tolazoline, and/or extracorporeal membrane oxygenation (ECMO). The three groups were identical for presenting symptoms, signs, and preoperative blood gas determinations. The survival for each group was as follows: group 1, 17 (40%) of 42; group 2, 14 (45%) of 31; and group 3, 12 (75%) of 16. Complications requiring further operations were identical. All survivors in groups 1 and 2 are normal developmentally, while one of five group 3 ECMO survivors has developmental delay and another has long-term ventilator dependence. These data suggest that ECMO, an invasive technique for newborn respiratory failure, improves survival in congenital diaphragmatic hernia.     

Haemophilus influenzae subtyping by SDS-PAGE of whole-cell polypeptides

Strains of Haemophilus influenzae isolated from patients in N.E. Scotland between 1983 and 1986 have been subtyped by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole-cell polypeptides. Gels were stained with Coomassie blue and polypeptide profiles were analysed using the Dice coefficient of similarity. Type b strains were all closely related, the 19 strains analysed being grouped at a 90% similarity level into one large (13 strains) and one small (3 strains) cluster with 3 strains being ungrouped. Thirty-six non-typable, epidemiologically unrelated strains were subtyped; one pair of strains had indistinguishable polypeptide profiles. The polypeptide profiles of the remaining strains showed much heterogeneity, although groups of strains isolated from the same patient over short periods showed indistinguishable profiles.     

Absorption of IgG does not enhance toxoplasma IgM and IgA immunoblotting.

Total IgG, IgM and IgA levels and toxoplasma IgG, IgM and IgA immunoblotting patterns were assayed in 10 sera before and after IgG absorption with Protein G-Sepharose 4. Removal of IgG (mean reduction 96%) was accompanied by a significant reduction in the level of IgM (mean reduction 56%) and IgA (mean reduction 53%) in nine of the 10 sera. The absorbed supernates showed fewer and weaker IgM bands in five sera, but IgA immunoblotting patterns were unaffected by absorption. There was no benefit in removing IgG in toxoplasma IgM and IgA immunoblotting.     

Toward an integrated understanding of dyslexia: genetic, neurological, and cognitive mechanisms.

This paper reviews what is known about developmental dyslexia at three levels of analysis: cognitive, neurological, and genetic. It also considers the difficult problem of establishing causal links between these levels of analysis, and argues that solving the gene-behavior problem is paradoxically easier than solving the brain-behavior problem.     

Leptin treatment induces loss of bone marrow adipocytes and increases bone formation in leptin-deficient ob/ob mice.

Normal mice and leptin-deficient ob/ob mice were treated with leptin to study effects on osteogenesis and adipogenesis in bone marrow. Leptin treatment significantly decreased bone marrow adipocyte size and number in ob/ob mice while increasing bone formation, BMC, and BMD. The results suggest that, in leptin-sensitive animals, the reduction in marrow adipocytes has positive effects on bone formation. INTRODUCTION: Adipocytes, osteoblasts, and osteoclasts have leptin receptors, and leptin can also affect bone metabolism indirectly through its receptors in the hypothalamus. We examined the effects of leptin treatment on bone formation, BMD, and marrow adipocyte population in normal mice and leptin-deficient ob/ob mice. MATERIALS AND METHODS: At the age of 15 weeks, mice were implanted with Alzet osmotic pumps for subcutaneous delivery of treatment solutions (saline, 2.5 microg leptin/day, or 10 microg leptin/day) for 14 days at a delivery rate of 0.25 microl/h. Bone formation was assessed using fluorochrome labels, cell populations were quantified using histomorphometry, and bone densitometry was measured using DXA. We also used a Luminex Beadlyte assay system to quantify cell survival markers in bone marrow samples. RESULTS AND CONCLUSIONS: Results indicate that both doses of leptin decreased the number of marrow adipocytes in ob/ob mice by >20% (p < 0.05) compared with PBS-treated ob/ob mice. The decrease in adipocyte number with leptin treatment is accompanied by an increase in concentration of the apoptosis marker caspase-3 in bone marrow adipocytes and hematopoietic cells. Both leptin doses also significantly (p < 0.05) increased the percentage of fluorochrome-labeled tibial endosteal surface by >30% compared with PBS-treated ob/ob mice. Leptin treatment increased whole body BMC by >30% in the ob/ob mice receiving the highest leptin dose. Leptin treatment provided no increase in bone formation, BMC, or BMD in normal, leptin-replete mice.     

Gram-negative bacterial pneumonia in the immunocompromised host

Gram-negative bacillary pneumonia is common in all groups of iatrogenically immunosuppressed patients. Mortalities are directly proportional to the degree of neutropenia. Those at particular risk for gram-negative pneumonia are neutropenic patients, patients residing in the hospital setting for prolonged periods, and patients in postoperative periods (eg, organ transplant recipients). The most frequent pathogenesis for pneumonia appears to be airway colonization with gram-negative bacilli, followed by lowe respiratory tract infection. Thus, attention to infection control measures and surveillance culture data is important. Because sputum production is scant or absent, and blood cultures positive in only 30% to 40% of patients, it is often difficult to identify specific etiologic agents. If bacterial pneumonia is suspected in the immunocompromised host, empiric antibiotic coverage should include drugs active against all common aerobic gram-negative bacilli (including P aeruginosa), plus S aureus. Most advocate a beta-lactam plus aminoglycoside combination. Adjunctive treatment with granulocyte transfusions should be reserved for patients not responding to traditional regimens. Immune therapy or prophylaxis has not been fully evaluated for the immunocompromised patient population.