Antibacterial activity and clinical efficacy of sparfloxacin in Mycobacterium avium-intracellulare complex infection.

In Japan the incidence of atypical mycobacteriosis has steadily increased, with Mycobacterium avium-intracellulare complex (MAC) the most common infecting organism. A standard chemotherapy regimen for MAC infection has not been established because of significant resistance to anti-mycobacterial drugs. Sparfloxacin has good antimicrobial activity against several acid-fast bacteria and is expected to be an effective drug for treating mycobacteriosis. We examined the effects of adding sparfloxacin to anti-tuberculotic combination therapy in six patients with MAC pulmonary disease. Drug susceptibility was also assessed using the agar dilution method. The minimum inhibitory concentrations (MICs) for sparfloxacin, levofloxacin, isoniazid, rifampicin, streptomycin, ethambutol and clarithromycin was measured in clinical isolates from all patients; sparfloxacin showed the lowest MIC. Bacteriological and clinical improvements were observed in the four patients who completed the study. Dosing was discontinued in two patients because of pruritic skin eruptions. Sparfloxacin shows promise as an anti-mycobacterial agent for treating MAC pulmonary disease.

[Clinical utility and safety of diagnostic thoracoscopy].

The increasing use of thoracoscopy performed under local anesthesia has made contributions to the diagnosis of pleural disease with effusion. During the past 7 years, we have performed 100 such thoracoscopy procedures using a flexible fiberoptic bronchoscope. On the basis of our clinical findings, we are able to discuss the utility and safety of this procedure. The causes of pleural effusion were carcinomatous pleurisy in 72 cases, tuberculosis pleurisy in 15 cases, infection without tuberculosis in 4 cases, malignant pleural mesothelioma in 8 cases and one case of asbestosis. The success rate of thoracoscopic pleural biopsies were 97% for carcinomatous pleurisy, 100% for malignant pleural mesothelioma and 86% for tuberculosis pleurisy. This procedure was performed with no serious effect on blood pressure, oxygen saturation, monitored ECG or BGA data, and with no serious complications. Therefore, we concluded that this method is very useful for the diagnosis of pleural effusions and has few complications.

A new approach to antiplatelet therapy: inhibitor of GPIb/V/IX-vWF interaction.

Evidence has been presented that the interaction between von Willebrand factor (vWF) and its platelet membrane receptor, the GPIb/V/IX complex, plays an important role in the pathogenesis of arterial thrombosis. A monoclonal antibody against the A1 domain of vWF has been shown to inhibit thrombus formation in the animal model of arterial thrombosis. Based upon these findings, a new approach to treating arterial thrombosis has been proposed by intervening in the interaction between vWF and platelet.

Antidepressant treatment of patients with diffuse esophageal spasm: a psychosomatic approach.

The cause of diffuse esophageal spasm (DES) has not been clearly established, and effective treatment is lacking. To determine whether a psychosomatic approach can be effective in treating DES patients, nine patients and 26 healthy volunteers were studied. Esophageal manometry and psychological testing were performed in both groups. The psychological background of the DES patients was investigated. Psychiatric diagnoses were made according to the criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders, 3rd edition, revised. The authors started psychosomatic treatment with isosorbide dinitrate for 1 month, then prescribed serotonin reuptake inhibitor antidepressants for an additional month. Anxiety and depression scores were substantially higher for the DES group than for the control group. Five of the nine DES patients (56%) were diagnosed as having major psychiatric disorders. Only one patient showed improvement with isosorbide dinitrate, and eight patients improved with antidepressants. These initial observations suggest that psychosomatic treatment with antidepressants may be effective in the treatment of DES.

High shear stress attenuates agonist-induced, glycoprotein IIb/IIIa-mediated platelet aggregation when von Willebrand factor binding to glycoprotein Ib/IX is blocked.

High shear stress facilitates von Willebrand factor (vWF) binding to platelet glycoprotein (GP) Ib/IX, causing activation of GPIIb/IIIa to induce platelet aggregation. Here we report that activated GPIIb/IIIa, even occupied by ligands, is not sufficient to mediate platelet aggregation under high shear stress conditions when vWF binding to GPIb/IX is blocked. Platelet rich plasma or washed platelet suspension supplemented with purified human fibrinogen at a concentration of 2 mg/mL were treated with an anti-vWF monoclonal antibody NMC-4 which blocks the binding of vWF to GPIb/IX. After addition of 10 mumol/L ADP, aggregation was continuously monitored under various shear stress conditions (0-108 dyne/cm2) using a cone-plate type aggregometer previously described (Ikeda Y et al J Clin Invest 1991; 87:1234). The extent of maximal aggregation of agonist-stimulated platelets in the presence of NMC-4 correlated inversely with the level of shear stress applied, with the virtual absence of aggregation at 108 dyne/cm2. Once aggregated by 10 mumol/L ADP under low shear stress (12 dyne/cm2), platelets could be disaggregated, in part, by the application of high shear stress (108 dyne/cm2), and reaggregated when shear stress was returned to 12 dyne/cm2. Flow cytometric analysis revealed that platelets stimulated with 10 mumol/L ADP at 108 dyne/cm2 bound fluorescein isothiocyanate (FITC)-labeled fibrinogen, although aggregation was absent in this experimental condition. These results demonstrate the dual effect of shear stress on platelet functions; a pro-aggregating activity that induces vWF-GPIb/IX interaction leading to platelet activation, and an anti-aggregating force to prevent the growth of platelet thrombi. It is suggested that the efficacy of vWF blockade is greater under high shear than low shear stress conditions, and that a selective inhibition of platelet functions can be possible.

Purification and cloning of a soluble ATP-diphosphohydrolase (apyrase) from potato tubers (Solanum tuberosum).

A soluble ATP-diphosphohydrolase (apyrase, EC 3.6.1.5) has been purified from potato tubers. Solanum tuberosum, to a specific activity of 10,000 mumol P(i)/mg/min. The cDNA corresponding to the potato apyrase has been isolated and termed RROP1. The deduced amino acid sequence contains a putative signal sequence, two hydrophobic regions at the carboxy terminus, two potential Asn-linked glycosylation sites, and four regions in the amino-terminal half that we term ACR (apyrase conserved regions) 1-4 that are highly conserved in known apyrases and related enzymes; garden pea nucleoside triphosphatase, Toxoplasma gondii nucleoside triphosphate hydrolases, and Saccharomyces cerevisiae golgi guanosine diphosphatase. A yeast 71.9-kDa hypothetical protein on chromosome V, a Caenorhabditis elegans hypothetical 61.3-kDa protein on chromosome III, and human CD39, a lymphoid cell activation antigen, also share the conserved ACR regions, but their ability to hydrolyze nucleotides has not been assessed.

Autologous blood transfusion for pulmonary and mediastinal surgery in 144 patients. The effectiveness of recombinant erythropoietin injection.

Preserved autologous transfusions have been performed for elective pulmonary and mediastinal surgery to prevent the adverse effects of homologous transfusions. Autologous blood was collected preoperatively from 144 patients. The collected blood volume ranged from 400 to 1,600 ml with a mean volume of 544 ml. In four patients with benign diseases, 1,200 to 1,600 ml of blood was collected using 3,000 U of intravenous recombinant human erythropoietin (rh-EPO) administered every other day. One hundred twenty-three of these patients (85 percent) did not require a homologous transfusion. In the 84 patients undergoing either a pneumonectomy, lobectomy, or segmentectomy, 68 (81 percent) avoided homologous blood exposure. A patient with rh-EPO who bled 2,000 g during surgery received an autotransfusion of only 1,400 ml and his postoperative course was uneventful. Preserved autologous blood collected after rh-EPO injections is an effective method for minimizing homologous blood transfusions in pulmonary and mediastinal surgery.

[Multicenter clinical evaluation of red cell concentrates stored up to 6 weeks in MAP, a new additive solution].

The clinical safety and efficacy of transfusion of red cell concentrates stored in MAP solution (MAP-CRC) containing mannitol, adenine, glucose, phosphate and citrate, into 39 anemic patients were evaluated. In 23 patients, infusion of MAP-CRC was alternated with infusion of ordinary CRC as a control. The MAP-CRC and CRC used in this study were stored at 4 degrees C for an average of 38.2 +/- 2.6 days (n = 52) and 18.1 +/- 2.2 days (n = 26), respectively. Red cell recovery was 77.5% for MAP-CRC and 82.5% for CRC, based on calculation of the increase in hemoglobin level one day after transfusion. There were no differences between patients transfused with MAP-CRC and those transfused with CRC in clinical findings or biochemical data. No major side-effects other than pyrexia associated with the underlying infections were seen in patients transfused with MAP-CRC. MAP-CRC stored up to 42 days is apparently as safe and effective as stored CRC. This new additive solution may therefore be useful for the future expansion of the indications for autologous blood transfusion by facilitating the collection and storage of more blood in the liquid state for a longer period, and may also be useful in obtaining more plasma from whole blood as source plasma.