Enhanced biosynthesis of extracellular matrix proteins and TGF-beta 1 by polyinosinic-polycytidylic acid during cutaneous wound healing in vivo

OBJECTIVES: We sought to determine the utility of left ventricular expansion velocities in differentiating constrictive pericarditis from restrictive cardiomyopathy. BACKGROUND: Several studies have shown that left ventricular diastolic expansion is influenced by the elastic recoil forces of the myocardium. These forces are affected by intrinsic myocardial disease but should be preserved when diastole is impaired as a result of extrinsic causes. METHODS: Using Doppler tissue imaging, we measured peak early velocity of longitudinal axis expansion (Ea) in 8 patients with constrictive pericarditis, 7 patients with restriction and 15 normal volunteers. Transmitral early (E) and late (A) Doppler flow velocities, left ventricular systolic and diastolic volumes, ejection fraction and mitral annular M-mode displacement were also compared between the groups. RESULTS: The Ea value was significantly higher in normal subjects (14.5 +/- 4.7 cm/s [mean +/- SD]) and in patients with constriction (14.8 +/- 4.8 cm/s) than in those with restriction (5.1 +/- 1.4 cm/s, p < 0.001 constriction vs. restriction). There was weak correlation between Ea and the extent of annular displacement (r = 0.55, p = 0.004) and the E/A ratio (r = 0.44, p = 0.03). There was no correlation between Ea and E (r = 0.33, p = 0.07) or ejection fraction (r = 0.21, p = 0.26). By multivariate analysis, Ea was the best variable for differentiating constriction from restriction. CONCLUSIONS: Our study indicates that longitudinal axis expansion velocities are markedly reduced in patients with restrictive cardiomyopathy. The poor correlation found with transvalvular flow velocities suggests that Ea may be relatively preload independent. The measurement of longitudinal axis expansion velocities provides a clinically useful distinction between constrictive pericarditis and restrictive cardiomyopathy and may prove to be valuable in the study of diastolic function.     

Distinct roles for the actin and microtubule cytoskeletons in the morphogenesis of epidermal hairs during wing development in Drosophila

We have found that the actin and microtubule cytoskeletons have overlapping, but distinct roles in the morphogenesis of epidermal hairs during Drosophila wing development. The function of both the actin and microtubule cytoskeletons appears to be required for the growth of wing hairs, as treatment of cultured pupal wings with either cytochalasin D or vinblastine was able to slow prehair extension. At higher doses a complete blockage of hair development was seen. The microtubule cytoskeleton is also required for localizing prehair initiation to the distalmost part of the cell. Disruption of the microtubule cytoskeleton resulted in the development of multiple prehairs along the apical cell periphery. The multiple hair cells were a phenocopy of mutations in the inturned group of tissue polarity genes, which are downstream targets of the frizzled signaling/signal transduction pathway. The actin cytoskeleton also plays a role in maintaining prehair integrity during prehair development as treatment of pupal wings with cytochalasin D, which inhibits actin polymerization, led to branched prehairs. This is a phenocopy of mutations in crinkled, and suggests mutations that cause branched hairs will be in genes that encode products that interact with the actin cytoskeleton.     

Atypical mycobacterial pulmonary disease and bronchial obstruction in HIV-negative children

Atypical mycobacterial infection in HIV-negative children usually presents with cervical lymphadenopathy. We report on 10 children who are HIV-negative and who presented with pulmonary disease, in whom either culture-proven atypical mycobacterium infection (four), positive avian Mantoux test (five), or lack of response to human tuberculosis treatment (one) had been observed. One case was subsequently diagnosed as chronic granulomatous disease and illustrates that children with atypical mycobacterial pulmonary infection should have their immune status fully investigated. Bronchial obstruction was observed in eight cases, and of these, endobronchial disease was found in six children. The diagnosis of atypical mycobacterial disease is difficult, and a negative avian Mantoux test does not exclude the diagnosis. The availability of clarithromycin and rifabutin has offered new therapeutic options in treating atypical mycobacterial pulmonary infection, but management of these cases can be prolonged and difficult.     

Anti-B-50 (GAP-43) antibodies decrease exocytosis of glutamate in permeated synaptosomes

The involvement of the protein kinase C substrate, B-50 (GAP-43), in the release of glutamate from small clear-cored vesicles in streptolysin-O-permeated synaptosomes was studied by using anti-B-50 antibodies. Glutamate release was induced from endogenous as well as 3H-labelled pools in a [Ca(2+)]-dependent manner. This Ca(2+)-induced release was partially ATP dependent and blocked by the light-chain fragment of tetanus toxin, demonstrating its vesicular nature. Comparison of the effects of anti-B-50 antibodies on glutamate and noradrenaline release from permeated synaptosomes revealed two major differences. Firstly, Ca(2+)-induced glutamate release was decreased only partially by anti-B-50 antibodies, whereas Ca(2+)-induced noradrenaline release was inhibited almost completely. Secondly, anti-B-50 antibodies significantly reduced basal glutamate release, but did not affect basal noradrenaline release. In view of the differences in exocytotic mechanisms of small clear-cored vesicles and large dense-cored vesicles, these data indicate that B-50 is important in the regulation of exocytosis of both types of neurotransmitters, probably at stages of vesicle recycling and/or vesicle recruitment, rather than in the Ca(2+)-induced fusion step.     

Olfactory thresholds for nicotine and menthol in smokers (abstinent and nonabstinent) and nonsmokers

Nonsmokers and smokers were compared for olfactory sensitivity to two odors associated with cigarettes: nicotine and menthol. Smokers were tested twice--while nonabstinent, and after 16-20 h of smoking abstinence. Smokers showed a higher olfactory threshold for nicotine than did nonsmokers, but the same threshold for menthol. Furthermore, when the smokers were abstinent, they showed a lower olfactory threshold for nicotine than when they were nonabstinent, but again, the same threshold for menthol. These results suggest a nicotine specific olfactory deficit in smokers that is reduced during abstinence.     

Pyomyositis in childhood: a case report

Pyomyositis is a primary infection of skeletal muscle. We report the case of a previously healthy six-year-old who suffered from pyomyositis in the right lower back. He presented with lower back pain and low-grade fever for one week. After a series of laboratory and imaging studies, the diagnosis of right multifidus muscle pyomyositis with abscess formation was made. The patient recovered rapidly after incision and drainage therapy, accompanied by antibiotic treatment. Methicillin-resistant Staphylococcus aureus was cultured from the abscess discharge. It was strongly suspected that herbal medicines and common cold medication the patient had been prescribed before admission to our hospital produced a masking effect that delayed the diagnosis.     

The effects of fibroblast growth factors in long-term primary culture of dystrophic (mdx) mouse muscle myoblasts

Neutralizing monoclonal antibodies specific for human interleukin-6 (IL-6) bind two distinct sites on the IL-6 protein (sites I and II). Their interference with IL-6 receptor binding suggested that site I is a receptor-binding site of IL-6, whereas site II is important for signal transduction. Mutagenesis of site II could therefore result in the isolation of IL-6 receptor antagonists. To test this hypothesis, a panel of IL-6 mutant proteins was constructed that did not bind to a site II-specific monoclonal antibody. One such site II mutant protein (with double substitution of Gln-160 with Glu and Thr-163 with Pro) was found to be an antagonist of human IL-6. It was inactive on human CESS cells, weakly active on human HepG2 cells, but active on mouse B9 cells. It could specifically antagonize the activity of wild-type IL-6 on CESS and HepG2 cells. The binding affinity of this variant for the 80-kDa IL-6 receptor was similar to that of wild-type IL-6. High affinity binding to CESS cells, however, was abolished, suggesting that the mutant protein is inactive because the complex of the 80-kDa IL-6 receptor and the mutant protein cannot associate with the signal transducer gp130. The human IL-6 antagonist protein may be potentially useful as a therapeutic agent.     

Restoration of localized severely atrophic maxillary ridge: case report

Phyllodes tumors are mixed tumors of the mammary gland. They account for 0.3 to 0.5 per cent of all breast tumors. This is a report on nineteen cases presenting phyllodes tumors. Depending on the number of mitoses, growth pattern and atypism degree, the neoplasms are classified as benign (12 cases), borderline (2) and malignant (5). Fourteen of them (9 with benign and 5 with malignant phyllodes tumors) undergo clinical follow-up study. A case with bilateral location of the neoplasm exhibiting strongly expressed susceptibility to relapse is described. The basic methods of preoperative diagnosis and the operative treatment procedures used are outlined.