Significance of the control serum measurement in infectious disease tests--a case of lot-to-lot variation of anti-HIV antibody assay kit

We are using infectious disease test kits consisting of positive serum diluted with negative pooled serum (P-S) and positive control (P-C). In two anti-HIV antibody tests the results for both P-S and P-C fluctuated between positive and negative depending on the lot No. of the reagent. In Western blot tests carried out to confirm the tests, the P-C was found to be positive and the P-S tests were both inconclusive. We speculated that the P-S had very weak antibodies that reacted differently from patient samples. Manufacturers of such kits, however, must supply reagents with appropriate reactivity, so it is important that they be informed of inconsistencies that could invalidate cut-off values and lead to false-positives and false-negatives.     

The effect of AH 21-132 on airway hyperresponsiveness induced by ozone exposure

We examined the effect of AH 21-132, which has been reported to relax airway smooth muscle and inhibit platelet activating factor (PAF)-induced airway hyperreactivity, on ozone-induced airway hyperresponsiveness (AHR) with airway inflammation in dogs. Airway responsiveness (AR) to methacholine was measured by modified Astograph (7 Hz oscillation method) before and after ozone exposure, and the numbers of neutrophils in the peripheral blood and total cell counts, differential cell counts and TXB2 in BALF were measured before and after ozone exposure. Ozone exposure was carried out for 2 hr at an ozone level of 3.46 +/- 0.10 ppm (mean +/- SE). There was a significant increase in AR to methacholine after ozone exposure (p less than 0.01), and the numbers of neutrophils in the peripheral blood and the total cell and neutrophil counts in BALF increased significantly (p less than 0.05). Pretreatment with AH 21-132 at an oral dose of 20 mg/kg significantly prevented the ozone-induced AHR to methacholine (p less than 0.01), and also inhibited the increase of neutrophil counts in the peripheral blood, and the total cell counts and the neutrophil counts in BALF after ozone exposure. There was no significant change in the levels of TXB2 in BALF before and after ozone exposure. In dogs not exposed to ozone, AR to methacholine and respiratory resistance to methacholine significantly decreased after administration of AH 21-132 at an oral dose of 20 mg/kg (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Influenza virus overcomes apoptosis by rapid multiplication

The kinetics of apoptotic fragmentation of the chromosomal DNA was determined in the influenza virus-infected MDCK, HeLa and KB cells, respectively. Comparison of these kinetics with the kinetics of virus multiplication revealed that the multiplication of influenza virus was observed only when apoptosis was induced after the production of progeny virus in the infected cells. The extent of apoptotic response was reversely correlated with the permissiveness of the cells.     

Long-term outcome of living related liver transplantation for patients with intrapulmonary shunting and strategy for complications

BACKGROUND: In 320 living related liver transplantation performed between June 1990 and September 1997, there were 21 living related liver transplantation for patients with intrapulmonary shunting, manifested by digital clubbing, cyanosis, and dyspnea. We report the long-term outcome for more 6 months and our strategy to overcome complications in these recipients. PATIENTS: A total of 21 patients (age range 2-33 years, 19 children and 2 adults, 6 males and 15 females) were classified into three grades according to shunt ratio calculated by TcMAA pulmonary scintigraphy; 5 in mild group (shunt ratio: less than 20%), 6 in moderated group (20%-40%), and 10 in severe group (more than 40%). The original underlying liver disease was biliary atresia in all patients. RESULTS: Spearmen's correlation coefficient rank test revealed that shunt ratio correlated significantly with PaO2 in room air (P=0.0001), PaO2 in 100% oxygen (P=0.0004), hematocrit (P=0.0276), and period of dyspnea before transplantation (P=0.023). COMPLICATIONS: Wound infection occurred in 80, 66, and 80%, and bile leakage in 20, 0, 40% in mild, moderate, and severe group, respectively. Patients who had portal vein thrombosis, and intracranial complication were classified as severe group and the incidence was 20 and 20%, respectively. The patient actuarial one year survival was 80, 66.7, and 48%, in mild, moderate, and severe group, respectively, although there was no significant difference. All patients who survived improved hepatopulmonary syndrome and the length of period required for the resolution was significantly correlated to the preoperative shunt ratio (P=0.023). COMMENTS: Patients with severe shunting are susceptible to wound infection and bile leak. The trend of higher incidence of portal thrombosis and intracranial complications in the severe group was closely related high hematocrit. Secure surgical technique to reduce bile leak and delayed primary wound closure to reduce wound infection were found to be effective. Anticoagulant therapy by infusing heparin through the portal vein followed by coumadin could prevent fatal portal vein thrombosis without counter risk of fatal cerebral hemorrhage.     

A study of factors influencing determination of discharge disposition of stroke rehabilitation patients]

PURPOSE: The purpose of this study is to statistically analyze medical and socioeconomic factors which influence discharge disposition from a stroke unit. METHODS: We investigated 126 stroke patients admitted to a community hospital within 30 days from the onset of the stroke. Mean age was 65.9 +/- 13.9 (SD) years old, profile of diagnosis was 89 infarctions was 37 hemorrhages, and mean length of stay was 79.7 +/- 45.1 days. Our rehabilitation team consists of doctors, nurses, physical therapists, occupational therapists and a medical social worker. Our stroke unit accepted the stroke patients from the time of admission and attempted to begin rehabilitation as soon as possible. The patients and their families were informed about their options after discharge from the hospital. Eight factors were analyzed using a multiple logistic regression model. RESULTS: 1) Ninety-eight patients (77.8%) could return home (home group) and 28 patients (22.2%) were discharged to another hospital or a long-term care facility (LTCF group). 2) Mean age of LTCF group (70.3 +/- 12.0) was significantly higher than the home group (64.8 +/- 14.2, p < 0.05). The home group showed milder leg paresis (p < 0.01), better Barthel index (p < 0.01), a higher number of family members (p < 0.05), and a better substantial care ability (p < 0.01) than LTCF group. 3) Three factors, higher Barthel index (odds ratio: 1.36), higher number of family members (1.84), and better substantial care ability (1.94), were found to facilitate discharge to home. Two other factors, hemorrhage (0.39) and public assistance (0.04), adversely affected the likelihood of discharge to home. CONCLUSIONS: This study suggests that a stroke unit could accelerate discharge home by improving the Barthel index. In addition, socioeconomic factors should be taken into consideration.     

Purification and Partial Characterization of an Indomethacin Hydrolyzing Enzyme from Pig Liver

Purpose. Indomethacin is well known to be metabolized via O-demethylation and N-deacylation. In this paper we found an enzyme involved in the hydrolysis of amide-linkage of indomethacin and partially characterized it as well as its substrate specificity. Methods. An indomethacin hydrolyzing enzyme was purified to homogeneity from pig liver microsomes using columns of Q-Sepharose, Red-Sepharose and Blue-Sepharose. The enzyme activity was assayed by measuring of -chlorobenzoic acid liberated from indomethacin by HPLC. Results. The purified enzyme effectively hydrolyzed the amide linkage in indomethacin but not those in -naphthylacetate and -nitrophenylacetate, which are typical substrates for carboxylesterase. The subunit molecular mass of the enzyme was 65 kDa according SDS-polyacrylamide gel electrophoresis. The Michaelis constant (Km) and maximum velocity (Vmax) values for indomethacin were 67.8 µM and 9.02 nmol/min/mg protein, respectively. The amino acid sequence analysis of the enzyme after cyanogen bromide cleavage showed high homology with a mouse carboxylesterase isozyme designated as ES-male. The activity of indomethacin hydrolysis was relatively high in the pig, rabbit and human liver homogenate, but not in those from rat and mouse. On the other hand, purified human liver carboxylesterases pl 5.3 and 4.5, and pig liver carboxylesterases have no catalytic activity for indomethacin. Conclusions. These results indicate that the hydrolysis of amide-linkage of indomethacin in humans would be associated with an enzyme similar to the indomethacin hydrolyzing enzyme from pig liver microsomes described here.     

Efficacy of methylprednisolone pulse and mild hypothermia therapies in patients with acute encephalopathy

Five patients with acute encephalopathy underwent methylprednisolone pulse (mPSL-P), hypothermia and their combination therapies (3 cases, 1 case and 1 case, respectively), with excellent outcome. Two cases with severe brain edema survived. One had severe brain damage as a sequelae. The remaining one recovered well after the combination therapy with mPSL-p and mild hypothermia, despite complete obstruction of the fourth ventricle on the first CT scan; the sequelae, hemiplegia and intelligent disturbance, was only mild. Four patients who received mPSL-P therapy within 6 hours after the onset of CNS symptoms recovered well though one was left with epilepsy. These results indicate that mPSL-P and/or hypothermia therapy will be chosen as the treatment of acute encephalopathy.     

Depressed natural killer cell activity due to decreased natural killer cell population in a vitamin E-deficient patient with Shwachman syndrome: reversible natural killer cell abnormality by α-tocopherol supplementation

Natural Killer (NK) cell activity was examined in a 16-month-old Japanese boy with Shwachman syndrome associated with severe vitamin E deficiency. As evaluated by ⁵¹Cr-release assay from K562 cells, NK cell activity was constantly decreased. After 8 weeks of oral α-tocopherol (α-Toc) supplementation (100 mg/day), NK cell activity had normalised. When α-Toc supplementation was interrupted for 16 weeks, NK cell activity again decreased. Flow cytometry of peripheral lymphocytes revealed a lowered number of CD16⁺ CD 56⁻ fraction, which has the most potent NK cell activity. Single cell-in-agarose assay, to investigate the binding and cytolytic activity of NK cell at the single cell level, revealed that the number of NK cells which bind to K562 cell was decreased, but that the cytolytic activity of the individual binding cell was relatively unaffected. A second supplementation of α-Toc for 8 weeks successfully restored NK cell activity, the number of cells expressing NK cell markers and the number of K562-binding cells as compared to the age-matched normal range. Conclusion These results indicate that severe vitamin E deficiency caused impaired NK cell activity due to a decrease in the number of CD16⁺ CD56⁻ NK cells and that this abnormality is reversible with α-Toc supple‐mentation. Received: 30 January 1996 and in revised form: 19 November 1996 / Accepted: 22 November 1996     

A double-blind randomised controlled trial of the effects of medroxyprogesterone acetate on bone density of women taking oestrogen replacement therapy

Objective To assess the effects of medroxyprogesterone acetate on bone density in women who have had a hysterectomy
Design Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy.
Participants One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice.
Interventions The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group.
Main outcome measure The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2–L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups.
Results At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipo-protein-2 cholesterol, and high density lipoprotein-2 triglycerides.
Conclusions Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholestrol and therefore may increase cardiovascular risk.     

Allelotype and replication error phenotype of small cell lung carcinoma

Allelotype and replication error (RER) phenotype analyses were performed to clarify the pathogenetic significance of inactivation of tumor suppressor genes and genomic instability in the genesis and progression of small cell lung carcinoma (SCLC). We examined 37 cases of SCLC for loss of heterozygosity (LOH) and microsatellite instability at 49 loci on all 39 nonacrocentric chromosomal arms. LOH was frequently (>70%) detected on chromosomes 3p (29/32, 90.6%), 5q (15/21, 71.4%), 13q (25/26, 96.2%), 17p (22/25, 88.0%), and 22q (24/33, 72.7%). Frequent LOH (>70%) on these loci was observed even among seven cases of stage I tumors. The incidence of LOH on all 39 nonacrocentric chromosomal arms was not significantly different between primary tumors and metastases. These results suggest that inactivation of multiple tumor suppressor genes accumulates relatively early during progression of SCLC and it may be responsible for clinically and biologically aggressive phenotype of SCLC. RER was observed in 6/37 (16.2%) of SCLC, however, RER at multiple loci was observed only in two cases. Therefore, it was indicated that genomic instability is uncommon, but might play a role in the genesis of a small subset of SCLC.