Lower Pacemaker in High Degree Atrioventricular Block is Modulated Electrotonically by Atrial Excitations

To see if the lower pacemaker in patients with atrioventricular (AV) block was modulated electrofonically by atrial excitation, we studied R-R intervals in two groups of AV block patients using a phase response curve (PRC). Group f consisted of 20 patients with high degree AV block, including seven patients in whom complete AV block was transiently observed in the course of acute inferior myocardial infarction. Group II consisted of 19 parents with complete AV block. In every patient, PRC was obtained from the continuous electrocardiogram by plotting each R₁-R₂ interval (response) on the ordinate as a function of the R₁-P_x interval (phase, x = 1, 2 …) on the abscissa, In Group I, the R-R interval was prolonged when the P wave fell in (he initial half of (he R-R interval, and was abbreviated when the P wave fell in the later half of the cycle. In Group II, the fluctuation of the R-R interval was minimum. In ten group I patients, with the improvement of the AV block, PRC became sharper and transition from prolongation to shortening occurred at shorter R-P intervals. We conclude that, in Group I, lower pacemaker was modulated electrotonicalIy by atrial excitations through decreased electrical coupling along the AV node.     

Synthesis and conformation of the trimeric coiled-coil segment of laminin*

A disulfide linked 95-mer parallel hetero-trimeric active site segment of laminin was designed and synthesised. The three subunits, A (32-mer), B1 (30-mer) and B2 (33-mer), were prepared by Boc-based solid-phase peptide synthesis involving a two-step trimethylsilyl bromide-thioanisole and HF deprotection procedure. The interlinking of the three subunits was accomplished by the stepwise selective formation of two disulfide bridges using air-oxidation and thallium (III) trifluoroacetate oxidation. The conformations of the synthetic peptides were studied by circular dichroism (CD) spectroscopy, showing that the hetero-dimer, B1-B2, one of the homo-dimers, B1-B1, and the trinier are 30 to 40% in the α-helical conformation in aqueous buffer. Variable temperature CD studies demonstrated that the trimer is considerably more stable (melting temperature (Tm) = 61°) than the hetero-dimer, B1-B2 (Tm = 36°).     

Stroke and meningitis in a case of SLE with anti-phospholipid antibodies

Anti-phospholipid antibodies (aPL) are concerned with many central nervous system diseases in systemic lupus erythematosus (SLE). However, no report has described the relationship between aseptic meningitis and aPL in SLE. We report a case of SLE with aPL, presenting cerebral infarction and aseptic meningitis. A 14 year old female with SLE with aPL experienced cerebral infarction and recurrent aseptic meningitis. Combination therapy with steroids and aspirin improved the condition and prevented relapses. The aPL are associated with cerebral infarction, even in young patients with SLE. In addition, aPL may induce aseptic meningitis in SLE.     

Prostate-specific antigen changes as a result of chlormadinone acetate administration to patients with benign prostatic hyperplasia: A retrospective multi-institutional study

BACKGROUND: Antiandrogens used to treat benign prostatic hyperplasia (BPH) may affect the diagnosis of prostate cancer by decreasing serum prostate-specific antigen (PSA) values. We conducted a retrospective survey of BPH patients treated with chlormadinone acetate (CMA) and analysed the effect of CMA on their PSA values. METHODS: A chart-based, retrospective, multi-institutional survey of clinically diagnosed patients with BPH who had been treated with CMA (Prostal; 50 mg/day) was conducted. The patients were divided into three groups according to their baseline PSA values: <4 ng/mL, Group I; >or=4 ng/mL and <10 ng/mL, Group II; and >or=10 ng/mL, Group III. The changes in the PSA values from baseline after 16, 26, and 52 weeks of CMA therapy were predicted using a nonlinear regression model analysis. RESULTS: Data from 192 of the 303 enrolled patients were analysed. The predicted percent changes from baseline among all patients after 16, 26, and 52 weeks of treatment were -49.6%, -49.8%, and -49.9%, respectively. The corresponding values were -42.4%, -43.7% and -43.8% in Group I; -57.4%, -58.4% and -58.5% in Group II; and -50.6%, -50.6% and -50.6% in Group III, respectively. CONCLUSION: The PSA values reached a nadir, approximately -50% of the baseline, after 16 weeks of CMA administration and remained at the same level thereafter. When CMA is used to treat BPH patients, the possibility of abnormal increases in PSA associated with prostate cancer must be considered; if prostate cancer is suspected, prompt testing, including a biopsy, should be performed.     

Preschool sarcoidosis mimicking juvenile rheumatoid arthritis: The significance of gallium scintigraphy and skin biopsy in the differential diagnosis

Preschool sarcoidosis occurring in children less than 6 years old is rare and characterized by the triad of skin, joint and eye manifestations without any pulmonary lesion. Because of similar clinical manifestations, the diagnosis of preschool sarcoidosis and juvenile rheumatoid arthritis (JRA) is confusing. A girl with preschool sarcoidosis, initially diagnosed and treated as having JRA, is reported here. Ophthalmologic examinations revealed posterior involvement of the eye. A gallium scintigram of the head showed panda appearance. Biopsy of the cutaneous lesion demonstrated non-caseating granuloma. Gallium scanning may be an important clue to correct diagnosis.     

Chronic Toxicity Carcinogenicity Studies of Triethanolamine in B6C3F1 Mice

The chronic toxicity and carcinogenic potential of triethanolaminewas examined in B6C3F1 mice. Triethanolamine, dissolved in distilledwater at levels of 0 (control), 1, and 2%, was given to groupsof 50 males and 50 females ad libitum in drinking water for82 weeks. Neoplasms developed in all groups, including the controlgroup, but no dose-related increase of the incidence of anytumor was observed in treated groups of both sexes. There wereno adverse effects as regards survival of the mice, organ weights,and specific incidence of neoplasms in the treated, comparedto the control group. This chronic toxicity test provides noevidence of carcinogenic potential of triethanolamine in B6C3F1mice.     

Sulfhydryl blocker-induced colitis in the rat: Immunological changes in thymus gland and colonic mucosa

The study was designed to examine the changes of thymus in sulfhydryl blocker-induced colitis. We used N-ethylmaleimide (NEM) as sulfhydryl blockers. Fasted male Sprague-Dawley rats were given 3% NEM in 1% methyl cellulose into the colon. N-ethylmaleimide treatment caused severe diarrhoea with bleeding for the first 7 days. At autopsy, adhesions, colon dilatation, and single or multiple erosions and ulcers were observed. Time-course studies revealed that the lesions were most extensive and severe 3 or 7 days after the administration of NEM. Histological examination of colon on the 3rd day after NEM treatment demonstrated mucosal erosion, oedema and extensive infiltration of neutrophils. The mucosal lesions extended into the submucosa and muscle on the 7th day after NEM treatment. Immunohistochemical studies showed that T cells and macrophages were markedly increased in the lamina propria of colonic mucosa. After 3 weeks, the infiltration of chronic inflammatory cells was observed and regeneration of the mucosa was noticed. The thymus gland was significantly decreased in weight and size on the 3rd day after NEM treatment, but the weight loss of thymus gland was regained in 3 weeks. Transient atrophy of thymus gland was noticed in this colitis model. The phenotypes of thymocytes were not influenced by NEM treatment. It is concluded that the thymus abnormalities in human ulcerative colitis are not induced in this animal model and that other chronic models are necessary for the elucidation of the immunological abnormalities, including thymus abnormalities.     

Addition of cisapride shortens colonoscopy preparation with lavage in elderly patients

Methods: The effect of pre-treatment with cisapride on colonoscopy preparation with lavage solution was compared in 120 out-patients less than 60 years and 73 out-patients 60 years or older, who were scheduled for total colonoscopy. By random allocation, patients were assigned to receive cisapride 10 mg or placebo 30 minutes before ingesting the magnesium citrate lavage solution. Results: The cleansing results and patients’acceptance did not differ significantly in the two treatment groups in either age group. The time from the start of ingesting magnesium citrate until the rectal effluent became clear was significantly shorter in cisapride-treated patients of 60 years or more. Moreover, the residual fluid volume removed by suction during colonoscopy was significantly less in the patients above aged 60 years who received cisapride. Conclusion: These findings indicate that the combination of cisapride and magnesium citrate is more effective than magnesium citrate alone in cleansing the colon for colonoscopy in elderly patients.