Substrate phosphorylation in the protein kinase Cgamma knockout mouse

The phosphorylation state of three identified neural-specific protein kinase C substrates (RC3, GAP-43/B-50, and MARCKS) was monitored in hippocampal slices of mice lacking the gamma-subtype of protein kinase C and wild-type controls by quantitative immunoprecipitation following 32Pi labeling. Depolarization with potassium, activation of glutamate receptors with glutamate, or direct stimulation of protein kinase C with a phorbol ester increased RC3 phosphorylation in wild-type animals but failed to affect RC3 phosphorylation in mice lacking the gamma-subtype of protein kinase C. Our results suggests the following biochemical pathway: activation of a postsynaptic (metabotropic) glutamate receptor stimulates the gamma-subtype of protein kinase C, which in turn phosphorylates RC3. The inability to increase RC3 phosphorylation in mice lacking the gamma-subtype of protein kinase C by membrane depolarization or glutamate receptor activation may contribute to the spatial learning deficits and impaired hippocampal LTP observed in these mice.     

Genitourinary anomalies in the CHARGE association

PURPOSE: We identified the incidence and types of genital and urinary anomalies, and established a plan for evaluating the urinary system in the CHARGE association. MATERIALS AND METHODS: We retrospectively reviewed the charts of 32 patients in whom the CHARGE association was diagnosed. RESULTS: Of the 32 patients identified 22 (69%) had genitourinary abnormalities. Genital anomalies, including micropenis, penile agenesis, hypospadias, chordee, cryptorchidism, a bifid scrotum, atresia of the uterus, cervix and vagina, and hypoplastic labia majora, labia minora and clitoris, were present in 18 patients (56%). Of the 24 patients who underwent renal ultrasound 10 (42%) were diagnosed with urinary tract anomalies including a solitary kidney, hydronephrosis, renal hypoplasia and duplex kidneys. Further evaluation revealed vesicoureteral reflux, neurogenic bladder secondary to spinal dysraphism, nephrolithiasis, ureteropelvic junction obstruction and a nonfunctioning upper pole in both duplex kidneys. CONCLUSIONS: There is a high incidence of genitourinary anomalies in the CHARGE association. Because of this high incidence of anomalies, patients with this condition should undergo a careful genitourinary evaluation, including renal and bladder ultrasound, and voiding cystourethrography screening.     

Cell-free apoptosis in Xenopus egg extracts: inhibition by Bcl-2 and requirement for an organelle fraction enriched in mitochondria

Apoptotic cell death involves a ritual series of morphological changes, presumably reflecting a conserved molecular pathway. We now report that the nuclear events typical of apoptosis can be reproduced in "apoptotic" Xenopus egg extracts. In this cell-free system, nuclear assembly and protein import are initially normal; after 2-4 hr, however, a process of nuclear destruction ensues involving chromatin condensation and the shrinkage and fragmentation of the nuclei. This apoptotic process, which also occurs in nuclei added exogenously, is blocked by the addition of baculovirus-expressed Bcl-2 protein. To block the disintegration of nuclei that are added later, Bcl-2 must be present during this latent period. "Apoptosis" in these extracts requires a dense organelle fraction enriched in mitochondria. The cell-free system described here provides a novel tool for understanding intracellular events in apoptosis and the inhibitory function of Bcl-2.     

Percutaneous large-core biopsy of papillary breast lesions

Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae possess the ability to cleave human IgA1 antibodies, and all successfully colonize and occasionally invade the human upper respiratory tract. N. meningitidis invades the bloodstream after a period of nasopharyngeal colonization. We directly compared levels of IgA1 protease activity in strains (n=52) derived from the cerebrospinal fluid or blood of patients with meningococcal disease with strains of N. meningitidis obtained from asymptomatic carriers (n=25). IgA1 protease activity was determined by a sensitive semiquantitative ELISA assay. Levels of IgA1 protease activity were significantly higher (P<0.0001) in strains associated with invasive meningococcal disease (98% with detectable activity, mean = 580 mU) than with those obtained from asymptomatic carriers (76% with detectable activity, mean = 280 mU). Despite marked variation in enzyme activity, almost all strains (96%) possessed the gene for IgA1 protease. Given the panmictic population structure of the bacterial isolates investigated, these data, obtained from two groups infected with N. meningitidis, but with markedly different clinical outcomes, provide the first quantitative evidence that IgA1 protease activity is a virulence determinant that contributes to the pathogenic phenotype, and suggest IgA1 protease as a potential target for prophylaxis.     

Vascular infections: medical and surgical therapies

Vascular infections are a serious problem, often associated with high morbidity and mortality. This article reviews the etiology, pathophysiology, risk factors, and treatment of surgical wound infections, prosthetic graft infections, aortoenteric fistulas (AEFs), and infected vascular ulcers. The primary cause of surgical wound infections is contamination by skin organisms during surgery. Prosthetic graft infections typically result from a progressive wound infection. Comorbid conditions are also related to vascular infections. Nurses should identify vascular patients at increased risk for infection, monitor them closely, and intervene to optimize the healing environment.