A field-focusing device to increase power output of ThermoRod trade mark implants for thermal ablation of tissue

Induction heating of small, cylindrical ferromagnetic implants (1.4 cm long and 1 mm in diameter) is a method for treating deep-seated tumors. These implants, or ThermoRods trade mark, are placed within a lesion in 1-cm(2) arrays and are exposed to an alternating magnetic field. The implants absorb energy from that field and transfer it as heat to the surrounding tissue. Each ThermoRod trade mark offers approximately 400 mW of power, and to kill cells, the target temperature must be greater than 42 degrees C. In this work, a magnetic field-focusing device is employed to concentrate the induced magnetic flux toward a local region near the base of the prostate to increase the power output of proximal ThermoRods trade mark. This, in turn, allows for more complete thermal ablation of lesions near the base of the prostate where the heat-sink characteristics of the bladder can cause significant power losses. Boundary element analysis and in vitro testing have shown that the use of a ferrofluid-based field-focusing device can lead to a significant increase in power output of approximately 25% and 13%, respectively, of proximal ThermoRods trade mark. These preliminary results indicate that the incorporation of such a ferrofluid-based focusing device into ThermoRod trade mark treatments is promising for the avoidance of significant power loss and for assuring complete thermal ablation of prostatic lesions.     

Facilitating visuospatial attention for the contralateral hemifield by repetitive TMS on the posterior parietal cortex

Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) could modulate the visuospatial functions. In this study, we investigated the effect of off-line high frequency subthreshold rTMS, when applied over the right or left posterior parietal cortex (PPC), on the visuospatial attention of the bilateral hemispaces. The subjects underwent visuospatial tasks before and immediately after receiving 1000 pulses of 10 Hz rTMS for a period of 20 min, and their responses were recorded. Our results demonstrated that the high frequency rTMS applied over the PPC produced facilitative effects on the visuospatial attention to the contralateral hemispace. The inhibitory effect to the ipsilateral hemispace was noticeable only in the left PPC.     

The effect of culture on the sex differences in schizophrenia

Cultural influences on sex differences in clinical characteristics and symptomatology of schizophrenia were studied among 369 schizophrenic patients from the United States and Turkey. Male schizophrenics were more likely to be single, and were younger than female schizophrenics at onset of symptoms and when first diagnosed, treated and hospitalised in both cultures. Turkish male and female schizophrenics were more ambivalent, inappropriate, "silly", euphoric, depersonalised, dissociated, mute, conceptually disorganised, and exhibiting more flight of ideas and thought than American male and female schizophrenics. Irrelevant thought and stereotypic behaviour were most severe in Turkish male and American female schizophrenics. Hallucinatory behaviour was most intense in Turkish separated, divorced, or widowed female schizophrenics and American married male schizophrenics. Turkish married female and Turkish separated, divorced, or widowed male schizophrenics were most disoriented. Turkish single female schizophrenics were most mute. Turkish separated, divorced, or widowed male schizophrenics showed most intense stupor behaviour.     

Effect of protease inhibitors on degradation of recombinant human epidermal growth factor in skin tissue

Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin, EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were incubated at 37°C for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin, EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for the treatment of open wound.     

Legionella micdadei prosthetic valve endocarditis

Summary Legionella usually causes pneumonia, but occasionally is in the differential diagnosis of culture negative endocarditis which sometimes involves prosthetic heart valves.Legionella prosthetic valve endocarditis is nearly always due toLegionella pneumophila and its clinical presentation is indistinguishable from other causes of prosthetic valve endocarditis. Diagnosis ofLegionella prosthetic valve endocarditis is by recovery of the organism from the blood, demonstration or isolation of the organism from the prosthetic heart valve, or by persistently highLegionella titers which are extremely elevated in prosthetic valve endocarditis compared toLegionella pneumonia. We believe this is the first case reported of prosthetic valve endocarditis caused byLegionella micdadei, and the first case ofLegionella prosthetic valve endocarditis with microscopic hematuria.

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Klappenprothesenendokarditis durchLegionella micdadei

Zusammenfassung Gelegentlich muß der PneumonieerregerLegionella in der Differentialdiagnose der kulturnegativen Endokarditis berücksichtigt werden, die manchmal auch Klappenprothesen befällt. Die Klappenprothesenendokarditis wird bei Legionellenätiologie fast ausschließlich durchLegionella pneumophila verursacht; in ihrem klinischen Erscheinungsbild ist sie von Klappenprothesenendokarditiden anderer Genese nicht zu unterscheiden. Die Diagnose wird durch Erregernachweis im But, in der entfernten Klappe oder durch sehr hoheLegionella-Titer nachgewiesen, die im Vergleich zur Legionellenpneumonie extrem stark erhöht sind. Wir gehen davon aus, daß unsere Fallmitteilung die erste Publikation einer Klappenprothesenendokarditis durchLegionella micdadei und der erste Fall mit Mikrohämaturie ist.

     

Inhibitory effect of the root ofCoptis japonica on catecholamine biosynthesis in PC12 cells

The effect of the root ofCoptis japonica (COPT), both the dichloromethane soluble (CH₂Cl₂) and insoluble (H₂O) fractions, on catecholamine contents and tyrosine hydroxylase (TH) activity in PC12 cells was investigated. CH₂Cl₂ and H₂O fractions showed 21 and 53% inhibitions on dopamine content, respectively, at a concentration of 40 μg/ml in medium: the H₂O fraction provided a greater inhibitory effect. The TH activity was reduced by the treatment of COPT (H₂O fraction). These results suggest that COPT has an inhibitory effect on the catecholamine biosynthesis by the reduction of TH activity in PC12 cells.     

Inhibition of C-terminal O-methyltransferase by a rat liver cytosolic peptide

The activity of S-famesylcysteine O-methyltransferase was assayed by incubating the enzyme with a syntheticin vitro substrate, [N-acetyl-S-trans, trans-famesyl-L-cysteine (AFC)], together with S-adenosyl-L-[methyl-¹⁴C]methionine. The resulting methylesterification product, [N-acetyl-S-trans, trans-famesyl-L-cysteine (methyl-¹⁴C) ester (AFCME)], was then analyzed either directly on HPLC or by converting the AFC[methyl-¹⁴C]ME to [methyl-¹⁴C] alcohol by basehydrolysis. Employing these two analytical methods, it was established that a peptide purified from rat liver cytosol fraction [Int. J. Biochem., 25, 1157 (1993)] strongly inhibited the above enzyme activity with IC₅₀ of 7.1X10^?8 M. Also, the S-famesylcysteine O-methyltransferase from several human colon cancer cells was also equally inhibited by the peptide.     

Ocular manifestations of AIDS

AIDS causes severe depression of the immune system through selective infection of CD4+ T lymphocytes. As such, certain infections and neoplasms occur in these patients often with ocular involvement. Among these, cytomegalovirus retinitis is by far the most common and remains a leading cause of visual loss. Intravenous ganciclovir and foscarnet, the two Food and Drug Administration-approved treatments for cytomegalovirus retinitis, are effective in most cases, but recurrences are the rule. In addition, these virustatic drugs require lifelong administration and dose-limiting toxicity affects many of these patients. Ongoing investigation into current and alternative therapies has produced some promising developments which are discussed here. Also reviewed are recent findings associated with other opportunistic pathogens and neoplasms that affect the eye in AIDS, including varicella-zoster virus, Toxoplasma gondii, and lymphoma.