Immunohistochemical characterization of extracellular matrix in the developing human cornea

Collagen, fibronectin and laminin are important components of the extracellular matrix of the human cornea. We used the immunofluorescence technique with polyclonal antibodies directed against these proteins and to bullous pemphigoid antigen (BPA), in order to study their distribution in human corneas from 8 weeks of gestation to term and in adult corneas. Immunoreactivity was observed with antibodies to type I collagen in the limbus and the corneal stroma at 8 weeks of gestation. At 11 weeks of gestation it was found in epithelial basement membrane (EBM) and Descemet's membrane (DM) and continued thus throughout fetal and adult life. Type II collagen was not detected in fetal or adult cornea. Type III collagen was detected during 8-20th weeks of gestation in the EBM, DM and stroma. After 27th weeks of gestation, type III collagen could no longer be detected in the central cornea. Type IV collagen was detected in the EBM as early as 8 weeks of gestation and remained positive throughout fetal and adult life. Descemet's membrane was negative for type IV collagen at 8 weeks of gestation and became positive thereafter. Immunostaining for fibronectin in DM was negative at 8 weeks of gestation, followed by patchy staining of corneal stroma and EBM up to the age of 37 weeks of gestation. Staining in the EBM was negative or variable up to 70 years of age, and then became positive again in a 77 year old individual. Staining for LN was positive in the EBM after 8 weeks of gestation. Staining was negative in DM at that age, but became positive after 9 weeks of gestation. Staining for BPA was negative at 8-9 weeks of gestation, then gradually became positive.     

Larvicidal effect of perbendazole on experimental infection of Angiostrongylus cantonensis in mice

Perbendazole was given orally and subcutaneously to mice infected with Angiostrongylus cantonensis at different stages of infection. The subcutaneous route of administration was more effective than the oral one. On the 5th day after infection, the perbendazole had a higher efficacy than on the 10th day postinfection. This finding shows that perbendazole had complete larvicidal effect at early stages of infection.     

RUGs and equity of access to nursing home care

Case-adjusted prospective reimbursement systems, such as resource utilization groups (RUGs), may promote nursing home cost containment, but they may do no better than existing systems at encouraging homes to admit the more dependent and thus costlier Medicaid patients, if the homes' reluctance to admit these patients is due to a shortage of nursing home beds. Using 1983 data on Wisconsin nursing homes, this paper presents evidence that suggests that the presence of excess demand, rather than low reimbursement rates, causes nursing homes to exclude the more costly Medicaid patients. Consequently, to benefit fully from RUGs, it is necessary either to eliminate excess demand (by increasing supply or decreasing demand) or to decide which patients have priority for admission and assign reimbursement payments to these patients that significantly favor these patients. Otherwise, access to nursing home care under RUGs is left to chance.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intrapartum fetal heart rate patterns and neonatal intraventricular hemorrhage

A goal for the obstetrician and neonatologist is to screen for risk factors associated with intraventricular hemorrhage (IVH) in the low-birthweight infant. Perinatal events that lead to neonatal metabolic and cardiovascular derangements seem to provoke IVH, and conflicting reports have implicated labor as being contributory. A fetal heart rate (FHR) abnormality during premature labor may be a predictor of subsequent neonatal IVH. For this reason, 5 years of FHR tracings at two university medical centers were reviewed for inborn infants who were delivered after premature labor and weighed less than or equal to 2000 gm. Sixty-four infants developed IVH, but pre-existing labor with a discernible FHR pattern was recorded in only 38 (59%) cases. Interpretations were reassuring in 17 (45%) cases, suspicious in 7 (18%) cases, and ominous in 14 (37%) cases. This proportion of FHR patterns was not significantly different from a matched group of premature infants without IVH during the same period. Interpretations of intrapartum FHR patterns of low-birthweight infants are limited, especially before 30 weeks gestation, and not useful in predicting neonatal IVH.     

Skin test results and self-reported symptom severity in allergic rhinitis: the role of psychological factors

BACKGROUND: In allergic conditions, the degree of skin test reactivity does not always correlate with the severity of clinical symptoms. Additional factors may contribute to the reported symptom severity. OBJECTIVES: To investigate the association between the magnitude of the skin prick test (SPT) response and the reported symptom severity in patients with allergic rhinitis and the possible modifying role of psychological factors. METHODS: One hundred four patients with allergic rhinitis and 23 with non-allergic rhinitis, classified according to their SPT response to 19 aeroallergens, were asked to rate the severity of five symptoms and to indicate whether their symptoms intensified on exposure to five common aeroallergens. They also completed a psychological questionnaire. Results Reported symptom severity of allergic rhinitis did not correlate with weal size for any of the aeroallergens tested or with the number of positive responses on SPT. It was not related to patient age, sex, or education. The reported symptoms severity correlated positively (0.29, P < 0.01) with reported symptom intensification on exposure to allergens. Moreover, both outcomes were positively associated with the psychological factors of hypochondriasis (0.20, P < 0.05 and 0.18, P < 0.05, respectively), and somatic awareness (0.24, P < 0.05 and 0.33, P < 0.01, respectively), but not with neuroticism. CONCLUSIONS: The severity of symptoms experienced by patients with allergic rhinitis is apparently not related to the magnitude of SPT response, but rather to psychological factors of hypochondriasis and somatic awareness. Physicians should be aware of the contribution of psychological factors to patient perceptions of the intensity of symptoms and of the intensification of symptoms on their exposure to allergens.