Portable microfocal radiographic devices for medical diagnosis

After the operation peritonitis have occurred in 19 patients, in 40--postoperative period course was without complications. The informativity of the laboratory investigations indexes for the postoperative course prognosis and early peritoneal cavity inflammation was revealed.     

Reactive electric-discharge sintering of TiN-TiB2

Powder mixtures based on titanium and its dihydrides are sintered by electric discharge in a certain current mode to produce TiN + TiB₂ composites. It is established that the use of tetragonal titanium hydride as the starting material results in the complete synthesis leading to a TiN + TiB₂ composite. The higher shrinkage rate results from the higher purity of titanium dihydride, which, in its turn, increases the partial pressure of hydrogen in the reaction area and the reaction rate. Tetragonal titanium hydride is more preferable than cubic hydride and metal titanium. The microstructure of alloys resulting from the sintering of hydride-based mixtures is more homogenous: it includes equiaxial grains with the mean size of about 1 µm.     

Mitomycin-C in congenital glaucoma

BACKGROUND AND OBJECTIVE: To evaluate the adjunctive use of mitomycin-C (MMC) during trabeculotomy and trabeculectomy for eyes with high-risk congenital glaucoma. PATIENTS AND METHODS: A prospective, randomized, double-blind study was performed to compare the effect of a single, 4-minute intraoperative exposure to 0.2 mg/ml (group 1) or 0.4 mg/ml (group 2) of MMC on trabeculotomy with trabeculectomy in 16 high-risk cases (30 eyes) of congenital glaucoma. RESULTS: The preoperative and final postoperative intraocular pressures (IOPs) of the two groups did not differ significantly. At the final follow-up, IOP control (< 21 mm Hg) without medications was achieved in 60% of the eyes in group 1 and in 86.67% of the eyes in group 2 (P = 21). With medication, IOP control was achieved in 86.7% of the eyes of each group. In both groups, the rate of surgical failure was 13.3%. Avascular, thin, sharply demarcated blebs were noted in 33.3% of the eyes from group 1 and in 66.67% of those from group 2 (P = .14). Intraoperative and postoperative hyphema and postoperative hypotony were the complications encountered in both groups, whereas serous choroidal detachment and wound leakage were seen only in group 2. CONCLUSIONS: Intraoperative MMC applied at a concentration of 0.2 mg/ml controlled postoperative IOP as effectively as a 0.4-mg/ml concentration in high-risk cases of congenital glaucoma, but with a lower incidence of complications and thin-walled blebs.     

Persistence of hepatitis C virus in newborn mice brain cell culture

A model of chronic infection of primary cultures of suckling mouse brain (SMB) cells actively producing hepatitis C virus (HCV) is developed. Destruction and repopulation of cells was observed for at least 6 months; this phenomenon was paralleled by virus release in culture medium. Persistent HCV contained in SMB cultures induced a cytopathogenic effect in PS, BHK-21, Vero, HAK, and click embryo cell cultures, its infective titers being 10.0-12.0 lg TCD50/0.2 ml. Persistent HCV formed heterogeneous plaques under agar in chick embryo cells. The polymerase chain reaction (PCR) regularly detected the HCV RNA at the stage of cell destruction in the culture fluid of HCV-infected cell cultures. The cytopathogenic activity of persistent HCV was neutralized by anti-HCV positive patients' sera with the neutralization index of 8.0-9.0 lg. The results of persistent HCV neutralization were confirmed by PCR. Immunofluorescence detected virus-specific HCV antigens in 15-40% of infected cells. Hence, the SMB-HCV system realized the cytopathogenic potential of HCV circulating in the blood of patients with hepatitis C. This system is promising for the study of the pathogenesis of HCV infection at a cellular level, for screening for specific and nonspecific antiviral agents, and for preparing native virus-specific proteins and RNA.     

Cytokine profiles of stimulated blood lymphocytes in asthmatic and healthy adolescents across the school year

T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation.     

Cytotoxicity of murine B lymphocytes induced by human VH4-34 (VH4.21) gene-encoded monoclonal antibodies

We previously found that a ventricular isovolumic pressure-time curve could be well fitted by the difference between two S-shaped logistic curves for the pressure rising and falling components, and called it "hybrid logistic" function: P(t)=A/[1+exp[-(4B/A)(t-C)]]-D/[1+exp[-(4E/D)(t-F)]]+G. We reported that the parameters of this hybrid logistic function are useful to characterize left ventricular contraction and relaxation comprehensively. In this study, we investigated how well this hybrid logistic function could fit the isometric twitch force-time curves of cross-circulated right ventricular papillary muscles of 7 dogs. This function precisely fitted the isometric force curves with correlation coefficients above 0.9996, much better than another fitting function (F(t)=C(t/A)(B)exp[1-(t/A)(B)]) proposed by Nwasokwa. The present results indicate that our hybrid logistic function can also reasonably express the canine right ventricular papillary muscle isometric twitch force-time curve. We suggest the possibility that the parameters of this hybrid logistic function are also useful to comprehensively characterize right ventricular papillary muscle twitch contraction and relaxation.     

Insulin therapy could prevent salt-induced high blood pressure in diabetes mellitus

The effectiveness of insulin replacement therapy in the prevention of salt-induced hypertension in diabetes mellitus was examined using Alloxan diabetic rats. Early daily (eight units/day) treatment with insulin prevented the development of high blood pressure after six weeks of high-salt feeding. The mean arterial pressure (MAP) for the early insulin-treated and salt-fed group (DET-SF) was 123.37 +/- 6.37 mmHg which was close to the value for normal (control) rats 128.17 +/- 4.84 mmHg, but significantly (p < 0.001) less than that of the untreated diabetic salt-fed group (DSF) which was 164.58 +/- 8.33 mmHg. The nondiabetic salt-fed (NDSF) group had MAP of 150.27 +/- 4.24 mmHg. Late commencement of insulin therapy did not significantly affect the sensitivity of the diabetic rats to high-salt diet. The results suggest that early commencement of insulin therapy could prevent the development of high blood pressure in diabetic rats.