Thin-layer chromatography on silver nitrate-impregnated silica gel for analysis of homemade tetrahydrocannabinol mixtures

Forensic Toxicology - Various forms of cannabidiol (CBD)-containing products are sold in Japan. CBD is easily converted to mixtures of ?9-tetrahydrocannabinol (?9-THC) and its isomer,...     

Successful catheter ablation of ventricular tachycardia originating from the idiopathic saccular apical left ventricular aneurysm

Left ventricular (LV) aneurysm has been recognized to frequently become a substrate of ventricular tachyarrhythmias. We report a case of a 66-year-old woman with symptomatic sustained monomorphic ventricular tachycardia (SMVT) originating from saccular apical LV aneurysm without definite underlying diseases. We performed catheter ablation using electroanatomical and conventional bipolar potential mapping. During SMVT, we found an area of fragmented potential -40 ms preceding the earliest wide QRS complex in the area of the apical LV aneurysm. Radiofrequency applications were delivered to this area. Since then, SMVT was no longer inducible by programmed electrical stimulation. The patient has remained free of VT recurrences during a subsequent 12-month follow-up period.     

Clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults

STUDY OBJECTIVE: To investigate the clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults. DESIGN: Prospective study. SETTING: Kawasaki Medical School Hospital, Kawasaki Medical School Kawasaki Hospital, and Kurashiki Daiichi Hospital in Japan. PARTICIPANTS: Forty patients with community-acquired pneumonia with C pneumoniae as the only pathogen identified admitted to three hospitals between April 1996 and March 2001 and their clinical presentations were compared to patients with Streptococcus pneumoniae and Mycoplasma pneumoniae pneumonia. MEASUREMENTS: The diagnosis of C pneumoniae infection was based on isolation and serologic testing of antibodies by the microimmunofluorescence test. RESULTS: The clinical presentations, except for shortness of breath, were similar for the three major etiologic agents. The mean temperature of C pneumoniae patients on hospital admission was 37.9 degrees C, which was lower than that of patients with S pneumoniae and M pneumoniae. The mean WBC count on hospital admission was lower in the patients with C pneumoniae (mean, 9,100/microL) than in those with S pneumoniae pneumonia but higher than in those with M pneumoniae pneumonia. No patients required respiratory support or admission to an ICU, and no deaths occurred among the C pneumoniae pneumonia patients. CONCLUSIONS: Our results indicate that C pneumoniae pneumonia as a single etiologic agent is mild and that the underlying conditions and clinical symptoms closely resemble those of S pneumoniae pneumonia. However, the physical examinations, laboratory findings, and prognostic factors of the C pneumoniae patients resembled those of patients with M pneumoniae pneumonia.     

Treatment for Churg-Strauss syndrome: induction of remission and efficacy of intravenous immunoglobulin therapy.

Churg-Strauss syndrome (CSS) is characterized by the presence of asthma, eosinophilia, and small-vessel vasculitis with granuloma. It is a distinct entity, as determined from all classifications of systemic vasculitis. The poor prognostic factors in CSS are renal insufficiency, cardiomyopathy, severe gastrointestinal (GI) tract, and central nervous systems (CNS) involvement. The initial management of CSS should include a high dose of a corticosteroid: prednisone at 1 mg/kg/day or its equivalent for methylprednisolone with tapering over 6 months. In patients with severe or rapidly progressing CSS, the administration of methylprednisolone pulse at 1 g/body/day for 3 days is recommended. When corticosteroid therapy does not induce remission, or when patients have poor prognostic factors, immunosuppressive cytotoxic therapy is indicated. However, some patients with severe CSS often show resistance to conventional treatment. We think that IVIG therapy is a hopeful candidate for second-line treatment for CSS patients, particularly in the case of neuropathy and/or cardiomyopathy, which are resistant to conventional therapy. However, there is not much evidence supporting the effectiveness of IVIG in CSS, and the mechanisms underlying the action of IVIG remain unclear. Now we are performing clinical trials of IVIG therapy for CSS patients who are resistant to conventional treatment, through a nationwide double-blinded placebo-controlled study in Japan.     

Dietary fish oil does not prevent doxorubicin-induced cardiomyopathy in rats

BACKGROUND: Dietary fish oil potentiates the susceptibility of cellular membranes to lipid peroxidation, although it is also known to have beneficial effects on the development of cardiovascular diseases. OBJECTIVE: The effects of dietary fish oil against doxorubicin-induced cardiomyopathy, in which free radicals and lipid peroxidation are involved, were investigated in rats. ANIMALS AND METHODS: Sprague-Dawley rats (100 g) were fed a standard diet or a high fish oil diet (containing 10% fish oil) throughout the experimental period. Four weeks after starting each diet, experimental rats were treated with doxorubicin (cumulative dose 15 mg/kg) or vehicle (0.28 M dextrose solution). After three weeks of doxorubicin treatment, the cardiac performance, myocardial lipid peroxidation and myocardial vitamin E level were assessed. RESULTS: Compared with control rats, doxorubicin-treated rats showed a significantly increased mortality rate (P<0.05), and significantly decreased systolic blood pressure and left ventricular fractional shortening (P<0.01). The myocardial thiobarbituric acid-reactive substance level was significantly higher in doxorubicin-treated rats than in control rats (P<0.01), while the myocardial vitamin E level was significantly lower (P<0.05). Dietary fish oil enhanced the myocardial lipid peroxidation caused by doxorubicin, which was associated with a further decrease in myocardial vitamin E level. As a result, the rats treated with both doxorubicin and the high fish oil diet showed the highest mortality rate and the lowest cardiac performance of all the experimental groups. CONCLUSIONS: Dietary fish oil may reduce antioxidant defences and accelerate susceptibility of the myocardium to lipid peroxidation in rats under doxorubicin treatment. This may partly explain why dietary fish oil does not prevent doxorubicin-induced cardiomyopathy.     

Direct demonstration of the cross-bridge recovery stroke in muscle thick filaments in aqueous solution by using the hydration chamber

Despite >50 years of research work since the discovery of sliding filament mechanism in muscle contraction, structural details of the coupling of cyclic cross-bridge movement to ATP hydrolysis are not yet fully understood. An example would be whether lever arm tilting on the myosin filament backbone will occur in the absence of actin. The most direct way to elucidate such movement is to record ATP-induced cross-bridge movement in hydrated thick filaments. Using the hydration chamber, with which biological specimens can be kept in an aqueous environment in an electron microscope, we have succeeded in recording ATP-induced cross-bridge movement in hydrated thick filaments consisting of rabbit skeletal muscle myosin, with gold position markers attached to the cross-bridges. The position of individual cross-bridges did not change appreciably with time in the absence of ATP, indicating stability of time-averaged cross-bridge mean position. On application of ATP, individual cross-bridges moved nearly parallel to the filament long axis. The amplitude of the ATP-induced cross-bridge movement showed a peak at 5–7.5 nm. At both sides of the filament bare region, across which the cross-bridge polarity was reversed, the cross-bridges were found to move away from, but not toward, the bare region. Application of ADP produced no appreciable cross-bridge movement. Because ATP reacts rapidly with the cross-bridges (M) to form complex (M·ADP·Pi) with an average lifetime >10 s, the observed cross-bridge movement is associated with reaction, M + ATP → M·ADP·Pi. The cross-bridges were observed to return to their initial position after exhaustion of ATP. These results constitute direct demonstration of the cross-bridge recovery stroke.     

p53 point mutations in primary human gastric carcinomas

Summary p53 point mutations in primary gastric carcinomas were analyzed by performing cDNA deoxynucleotide sequencing of the gene. Out of 16,9 (56.3%) primary gastric carcinoma cases, including early cancer, showed one or more p53 point mutations in their open-reading frame, and 4 out of 9 cases had a p53 point mutation within highly conserved domains. The characteristics of the p53 mutation spectrum observed in primary tumors were (a) frequent mutation at an A:T pair (50%, 7 out of 14 mutations), (b) high transversion incidence (29%, 4 out of 14 mutations), (c) no transition at CpG, and (d) no G:C to T:A transversion. Our results suggest that p53 mutation is a common event in gastric carcinoma occurring from the early stage of progression with its specific mutation spectrum.Abbreviation PCR-SSCP polymerase chain reaction single-strand conformation polymorphism     

Chronic necrotizing pulmonary aspergillosis in pneumoconiosis: clinical and radiologic findings in 10 patients.

STUDY OBJECTIVE: To characterize clinical, radiographic, and CT findings of chronic necrotizing pulmonary aspergillosis (CNPA) in patients with pneumoconiosis. METHODS: We studied 10 patients with pneumoconiosis who were seen at Asahi Rosai Hospital and received a clinical diagnosis of CNPA during a 15-year period, and detailed the long-term clinical and radiologic courses of four cases. RESULTS: All patients were men, ranging in age from 48 to 77 years (mean, 60.1 years). Their occupational histories included pottery making (n = 9) and coal mining (n = 1). Chest radiographic findings by the International Labor Organization profusion grading system were greater than category 2. All patients were symptomatic, with a productive cough, hemoptysis, and dyspnea. Serum findings were positive for the Aspergillus antibody in seven patients. The radiologic findings consisted of parenchymal infiltrates and cavities mostly containing mycetoma, which generally involved the upper lobes. The disease progressed slowly; in one patient, broad destruction of the lung was observed after > 10 years without antifungal administration. Most of the patients experienced clinical and radiologic improvement after receiving antifungal therapy, by oral, inhaled, or intracavitary administration. CONCLUSIONS: Chronic persistent or progressive upper-lobe infiltrates and cavities in patients with pneumoconiosis should raise the possibility of CNPA. Early diagnosis and initiation of effective therapy are recommended to achieve a better outcome.