Cloning of serum RNA associated with hepatitis C infection suggesting heterogeneity of the agent(s) responsible for the infection

Fifty-six lambda gt11-random-primed-cDNA recombinants of which translation products react with antibodies in the serum drawn from patients with hepatitis C (blood-borne non-A, non-B hepatitis) were cloned from serum pooled from donors presumably infected with hepatitis C. The specificity of these clones for hepaitits C infection was determined using 3 test panels. Of these 29 clones were determined to be specific for Japanese hepatitis C infection. However one of the 29 clones was positive for 1 out of 5 normals in an American test panel while 12 clones were positive for the American panel as well. The remaining 28 clones reacted well with serum from transfusion associated chronic hepatitis C comparing to the sporadic cases in the Japanese panel. When they were tested with normal donors, another clone reacted with a distinct donor group with which the other clones did not react. These results may suggest the presence of heterogeneity in Japanese hepatitis C.     

Effect of the calcium antagonist,diltiazem, on beta-agonist-induced reduction of beta-adrenergic responsiveness in the guinea pig lung

This study was designed to clarify the mechanism of tolerance that occurs during prolonged administration of a beta-agonist in relation to membrane phospholipid degradation and to elucidate the effect of diltiazem, a calcium antagonist. Guinea pigs were divided into 3 groups: (1) control—physiological saline (0.5 ml) was injected once a day for 7 successive days; (2) metaproterenol (Mp)—Mp was injected intraperitoneally (10 mg/kg/day) for 7 successive days; (3) Mp + diltiazem—diltiazem was injected intraperitoneally (20 mg/kg/day) 30 min before Mp injection for 7 successive days. The number of beta-adrenoceptors and the 10⁻⁵ M (−)-isoproterenol-stimulated adenylate cyclase activity were significantly decreased in the metaproterenol group. Diltiazem reduced these decreases. Phospholipase activity was increased and phosphatidylcholine and phosphatidylethanolamine levels were decreased in the metaproterenol group. Diltiazem also reduced these changes. These results suggest that the degradation of membrane phospholipids by phospholipase may be involved in a decrease in beta-adrenergic response caused by successive administration of metaproterenol. Diltiazem protects membrane phospholipids from phospholipase attack, which in turn maintains beta-adrenergic responsiveness. Part of this study was presented at the Annual Meeting of the American Thoracic Society, May 12, 1987, New Orleans, Louisiana     

Progressive nature of paroxysmal atrial fibrillation. Observations from a 14-year follow-up study.

BACKGROUND: Atrial fibrillation (AF) is believed to occur first as paroxysmal, then be gradually perpetuated, and finally become chronic as the end result. However, this presumed clinical course has not been well confirmed. METHODS AND RESULTS: The clinical course of recurrent paroxysmal AF (PAF) from its onset was examined in 171 patients (mean follow-up period: 14.1+/-8.1 years). This study population consisted of patients with no structural heart disease (n=88), ischemic heart disease (n=28), dilated or hypertrophic cardiomyopathy (n=17), valvular heart disease (n=35) or other cardiac diseases. The mean age at the onset of AF was 58.3 +/-11.8 years old. During the mean follow-up period of 14.1 years, PAF eventually developed into its chronic form in 132 patients under conventional antiarrhythmic therapy (77.2%, 5.5% of patients per year). The independent factors for early development into chronic AF were aging (hazard ratio (HR) 1.27 per 10 years, 95% confidence interval (CI) 1.06-1.47)), dilated left atrium (HR 1.39 per 10 mm, 95% CI 1.11-1.69), myocardial infarction (HR 2.33, 95% CI 1.13-4.81), and valvular diseases (HR 2.29, 95% CI 1.22-4.30). CONCLUSIONS: The present long-term observations definitely and quantitatively revealed the progressive nature of PAF.     

Significance of Pseudomonas aeruginosa colonization of the gastrointestinal tract

OBJECTIVE: This study was conducted to determine the association between gastrointestinal (GI) colonization and the development of invasive Pseudomonas aeruginosa infections and risk factors for acquisition of P. aeruginosa colonization in gut. METHODS: All stool specimens sent for microbiological examination were cultured for P. aeruginosa search for three years. PATIENTS AND MATERIALS: P. aeruginosa had been isolated from stool of 207 patients for three years. Of the 207 patients, 87 patients were identified P. aeruginosa-colonized patients. RESULTS: Forty-five (52%) were exposed to previous invasive procedures and eighty-three (95%) were prescribed antibiotics before the isolation of P. aeruginosa. Fourteen distinctive P. aeruginosa infections were developed in 13 patients (15%). Infections associated with GI colonization included 4 pneumonia, 4 urinary tract infection, 3 skin infection, and 3 bacteremia. The age, gender, underlying diseases, previous invasive procedures, and the duration of hospitalization were not significant. Twelve (34%) patients were diagnosed with ileus and three (9%) were undergoing gastrostomy during the acquisition of P. aeruginosa colonization in gut. CONCLUSION: Gastrointestinal disorders, especially obstruction and surgical interventions, are also important for the acquisition of by P. aeruginosa, in the GI tract.     

Effect of ethanol on endothelin-1 release from gastric vasculature

The effects of ethanol on gastric vasculature in isolated vascularly perfused rabbit stomach was investigated. The isolated stomach was perfused with Krebs-Henseleit solution containing 3% dextran bubbled with 95% O₂ and 5% CO₂ at a rate of 12 ml/min. After mixture and perfusion of 10 mM to 400 mM of ethanol, perfusion pressure and endothelin-1 concentration in effluent from gastric vasculature were measured. Perfusion pressure and endothelin-1 concentration in effluent increased in a dose-dependent manner with increasing ethanol concentrations. In conclusion, the data suggest that ethanol may stimulate the release of endothelin from gastric vasculature and may cause gastric ischemia due to vasoconstriction resulting in acute gastric mucosal injury.     

A case of malignant peritoneal mesothelioma successfully treated with systemic chemothrapy

A 64-year-old man with a 2-month history of abdominal distension was admitted for transient cerebral ischemic attack. A CT scan revealed massive ascites. Laparoscopy showed multiple whitish nodules on the visceral peritoneum and the omentum. Peritoneal biopsy revealed tumor cells consistent with malignant peritoneal mesothelioma (MPeM). Pemetrexed in combination with cisplatin was administered because it has been reported to be active in patients with MPeM. However his disease progressed. As second-line therapy paclitaxel was tried which yielded a complete response (CR). Eighteen months later he developed abdominal pain of the right upper region where a CT scan showed a mass with surrounding inflammation. As third-line therapy, gemcitabine was administered and again resulted in a CR. He is alive at 3 years from first presenting. Searches for case studies published in medical journals on MPeM were carried out, and 59 cases were analyzed in comparison with this case.     

In vivo pre- and postoperative three-dimensional knee kinematics in unicompartmental knee arthroplasty

Background

Pre- and postoperative knee kinematics in unicompartmental knee arthroplasty (UKA) can be theoretically related to clinical outcome and longevity after UKA with regard to ligament function and the degree of arthritic changes. However, the preoperative knee kinematics of patients indicated for UKA remain to be elucidated, and it is also unclear whether the preoperative kinematics can be maintained by the UKA procedure. The objective of this study was to examine the in vivo pre- and postoperative three-dimensional knee kinematics in UKA while referencing the normal knee kinematics reported in our previous study.

Methods

We analyzed the knee kinematics in 17 knees (14 patients) undergoing UKA via a three-dimensional to two-dimensional registration technique employing femoral condylar translation and femoral axial rotation. The pre- and postoperative knee kinematics during squat motion were evaluated in the same subjects, employing consistent evaluation parameters.

Results

On average, both pre- and postoperative knee kinematics in the range 10–100° of knee flexion demonstrated near-consistent femoral external rotation and anterior translation of the medial condyle and posterior translation of the lateral condyle. However, the mean femoral external rotation angle and the posterior translation of the lateral condyle postoperatively were significantly smaller than the values observed preoperatively.

Discussion

Although the patterns of preoperative knee motion were similar to those seen in normal knees, the magnitude of this motion varied widely between patients, so it was not necessarily representative of normal knees. These variations may be due to the varying degrees of arthritic changes caused by osteoarthritis. Although the patterns of knee kinematics were largely maintained by the UKA procedure, the causes of the significant reductions in the magnitude of motion upon performing the UKA procedure should be investigated in subsequent studies with a larger number of patients.