Viral hepatitis comparative epidemiology

The epidemiology of HAV, HBV, HCV, HDV and HEV is compared. Spread of HAV and HEV is by the faecal/oral route whereas HBV, HCV and HDV are spread by blood or blood products. HEV is more likely to produce large epidemics than HAV but sporadic cases also occur. HBV, HCV and HDV all occur after blood transfusion, in haemophiliacs and intravenous drug abusers but they differ in their geographical distribution and in the frequency of perinatal transmission which is only common with HBV. Superinfection and interaction between these viruses is discussed.

Endotoxin and bacterial contamination of dialysis center water and dialysate; a cross sectional survey

The bacterial and endotoxin levels of purified water and effluent dialysate were examined in a cross section of dialysis centers in the central United States. All samples were collected within a four-hour drive of the University of Louisville and were collected, processed and analyzed by our personnel, to eliminate variability in sample handling. A medium capable of higher bacteria recovery from aqueous environments than those ordinarily employed in clinical assays was used. Endotoxins were determined by a quantitative colorimetric assay. By the more sensitive bacterial assay 53% of the centers had bacterial counts above the AAMI standard of 200 colony-forming units per ml (CFU/ml) for water and 35% of the centers had bacterial counts above the 2000 CFU/ml standard for dialysate in at least one sampling period. The samples showed 35% and 19% of water and dialysate above the standards, respectively. While there are no standards for endotoxin concentrations in water used to prepare dialysate, 2% of the centers had endotoxin levels in their water above five endotoxin units per ml (5 EU/ml = 1 ng/ml in our assay kit), the limit set by the AAMI standards for reprocessor water. Both bacterial and endotoxin levels tended to be elevated in dialysate, with the highest levels of endotoxin in dialysates posing an obvious potential risk when high-flux dialyzers are used.

Correlates of willingness to consider organ donation among blacks

Professionals in the health care and organ procurement fields reveal that black Americans display limited commitment to organ donation. The present study represents an attempt to shed some light on this issue by examining the relationship of selected demographic, knowledge and attitude-belief variables to willingness to consider organ donation within a black population. Findings indicated that only a few of the demographic and knowledge variables were related to willingness to consider organ donation. All of the attitude-belief variables, however, were found to be significantly associated with the dependent variable. Implications of the findings for recruiting black organ donors and future research are discussed.

Evidence for specificity in the encapsidation of Sindbis virus RNAs

We investigated the interaction of the capsid protein of Sindbis virus with Sindbis viral RNAs and defined a region of the genome that is required for binding in vitro and for packaging in vivo. The binding studies were performed with purified capsid protein immobilized on nitrocellulose and 32P-labeled RNAs transcribed in vitro from viral and nonspecific cDNAs. Genomic and defective interfering (DI) RNAs bound capsid protein significantly better than either the subgenomic (26S) RNA or nonspecific RNAs. Transcripts prepared from either truncated or deleted cDNAs were used to define the segment required for binding. This segment, which is represented twice in DI RNA, lies between nucleotides 746 and 1226 of the genomic RNA and is within the coding region of the nonstructural protein nsP1. Insertion of a domain covering these sequences into a nonviral RNA was able to convert it from a background level of binding to an activity that was 80% that of the Sindbis virus DI RNA. We analyzed DI RNA transcripts in detail because they could be studied not only for the ability to bind capsid protein in vitro but also for the ability to be replicated and packaged in vivo in the presence of helper virion RNA. The results obtained with three DI RNAs are reported. One (CTS14), which has one copy of the binding domain, bound efficiently to capsid protein in vitro and was packaged in vivo as measured by amplification on passaging. In contrast, a DI RNA (CTS1) which lacked this region did not bind to capsid protein and was not detected on passaging. By using lipofectin (P. L. Felgner, T. R. Gadek, M. Holm, R. Roman, H. W. Chan, M. Wenz, J.P. Northrop, G. M. Ringold, and M. Danielson, Proc. Natl. Acad. Sci. USA 84:7413-7417, 1987) to enhance RNA uptake, we were able to demonstrate that CTS1 RNA was replicated in the transfected cells. It was replicated to the same level as another DI RNA (CTS253) which has only the 3' 279 nucleotides of the binding domain and these are located near the 3' terminus of the RNA. CTS253 bound capsid protein to an intermediate level but was amplified on passaging. The binding studies and the in vivo packaging data, taken together, provide strong support for the conclusion that there is a specific capsid recognition domain in Sindbis virus RNA that plays a role in nucleocapsid assembly.

Paraplegia following intra-aortic balloon support. Report of a case

A case is presented of paraplegia associated with the intra-aortic balloon pump used in a post-operative patient. The published experience with this complication is reviewed.

Cirrhosis in partial lipodystrophy

A patient with partial lipodystrophy, fatty liver and cirrhosis, and autoimmune thyroid disease is described. Treatment with thyroxine led to partial improvement in the hepatic abnormality.

Bacterial contamination of hemodialysis center water and dialysate: are current assays adequate?

Many dialysis centers depend on clinical laboratories or a commercially available dip culture to determine the contamination levels in water and dialysate. To determine whether these standard clinical culture procedures adequately quantitate bacterial contamination in hemodialysis center water and dialysate, test results of two routine clinical media was compared, trypticase soy agar (TSA) and plate count agar (PCA), with those of nutrient-poor R2A medium. Dialysate samples demonstrated significant differences in media, the temperature of incubation, and plating techniques (pour plate versus spread plates). Purified water for dialysis demonstrated significant differences only for media; however, temperature was an important variable. Selective growth on R2A agar of some water- and dialysate-contaminating species was studied by velvet disk and loop transfer of colonies. A strong selectivity for water-borne bacteria was demonstrated by R2A agar; the bacteria that did not grow on TSA and PCA have been identified.

The flow/volume curve as a mass screening test with emphasis on quality control

Air flow through the airways is influenced by different mechanical characteristics of the respiratory system and can be affected by pathological changes in the lungs. Lung volume is probably the most important independent variable determining air flow through the airways. Therefore, it is logical that lung volume should form the ordinate of a curve used to demonstrate the variation of airflow through the airways during forced inspiratory and expiratory manoeuvres. The flow/volume curve is in many ways superior to other measurements of lung function for clinical and epidemiological assessments. Most of the problems that have to be overcome in obtaining satisfactory and repeatable flow/volume curves are discussed and illustrated. A computer system which optimises quality control is described. By making use of this system, operator error can be reduced to a minimum. It is recommended that hard copies of the three efforts must be available and that all flow/volume measurements be controlled by a knowledgeable person before the results are entered in the records.

A comparison of oral milrinone, digoxin, and their combination in the treatment of patients with chronic heart failure

We randomly assigned 230 patients in sinus rhythm with moderately severe heart failure to treatment with digoxin, milrinone, both, or placebo. The effects of each were compared during a 12-week, double-blind trial. Treatment with milrinone or digoxin significantly increased treadmill exercise time as compared with placebo (by 82 and 64 seconds respectively; 95 percent confidence limits, 44 and 123, and 30 and 100). Both treatments reduced the frequency of decompensation from heart failure, from 47 percent with placebo to 34 percent with milrinone (P less than 0.05; 95 percent confidence limits, 22 and 46) and 15 percent with digoxin (P less than 0.01; 95 percent confidence limits, 7 and 26). However, the clinical condition of 20 percent of the patients taking milrinone deteriorated within two weeks after treatment was begun, as compared with only 3 percent of those taking digoxin (P less than 0.05). The left ventricular ejection fraction at rest was not significantly changed by milrinone (+0.2 percent; 95 percent confidence limits, -1.5 and 1.9), but it was increased by digoxin (+1.7 percent; P less than 0.01; 95 percent confidence limits, -0.03 and 3.4) and decreased by placebo (-2.0 percent; 95 percent confidence limits, -3.8 and -0.1). Three-month survival was related inversely to the base-line ejection fraction. Analysis of mortality from all causes according to the intention to treat suggested an adverse effect of milrinone (P = 0.064). After adjustment for an excess of patients with lower ejection fractions randomly assigned to receive milrinone, this trend was not significant (P = 0.26). Increased ventricular arrhythmias occurred more frequently in patients who received milrinone than in those who did not (18 vs. 4 percent; P less than 0.03). We conclude that milrinone significantly increased exercise tolerance and reduced the frequency of worsened heart failure. However, in the population of patients studied, milrinone or the combination of milrinone and digoxin offered no advantage over digoxin alone. Furthermore, our data suggest that milrinone may aggravate ventricular arrhythmias.

Analysis of the wheal-and-flare reactions that follow the intradermal injection of histamine and morphine in adults with recurrent, unexplained anaphylaxis and systemic mastocytosis

It has been suggested that patients with recurrent, unexplained anaphylaxis may be more responsive, and patients with systemic mastocytosis, less responsive, to mast cell-derived mediators, including histamine, compared to normal subjects. This would help explain why patients with recurrent, unexplained anaphylaxis have an anaphylactic response and, conversely, why patients with systemic mastocytosis can tolerate high levels of plasma histamine. To test this hypothesis, intradermal titrations (0.02 ml of solution from 1 ng/ml to 2 micrograms/ml) of histamine and morphine sulfate (MS) (10 ng/ml to 10 micrograms/ml) were administered to normal volunteers (N = 15), patients with recurrent, unexplained anaphylaxis (N = 10), and patients with systemic mastocytosis (N = 18). Antihistamines were stopped at least 72 hours before the study. Resultant areas of wheal and flare were determined with a computerized morphometric system. Comparison of any two given means at each dose of histamine or morphine with the two-sample Student's t test with Bonferroni inequality demonstrated no significant differences (p greater than 0.05) among the three groups. The median amount of MS or histamine required to produce a half-maximal response was compared for equality. None of the differences observed reached statistical significance, in agreement with the similarity of the dose-response curves. An analysis of the correlation between response to MS and to histamine in individual subjects revealed the responses to be significantly correlated in all cases, with the exception of wheal in patients with recurrent, unexplained anaphylaxis.(ABSTRACT TRUNCATED AT 250 WORDS)

Transmission electron microscopy and immunocytochemical studies of yeast: analysis of HMG-CoA reductase overproduction by electron microscopy

The results and anecdotes presented here are intended only as a general guide to other would-be immunocytochemists, because other proteins will undoubtedly respond at least somewhat differently than does HMG-CoA reductase. Nevertheless, based on these experiences, we offer the following suggestions: 1. Antiserum of high specificity should be raised and affinity-purified. Using this antiserum, immunofluorescence microscopy should be attempted before resorting to electron microscopic localization. In the absence of immunolocalization at the light-microscope level, it may be a waste of time to pursue the problem to higher levels of resolution. 2. Cells should be prefixed in 1% formaldehyde-1% glutaraldehyde. Direct fixation of the growing culture and use of phosphate buffer are recommended. The prefixed sample can then be divided into two or three aliquots. One aliquot should receive no postfixation (for optimal immunoreactivity), while the others can be postfixed in osmium-potassium ferricyanide (for possible immunolocalization) or permanganate (for ultrastructural analysis). Because of its ease of use, Spurr's resin should be tried initially. If immunocytochemistry is successful, no further preparations are necessary. If unsuccessful, LR White resin is recommended, but the sample must be treated to remove the cell wall. Electron microscopy and immunocytochemistry offer views into the molecular arrangement of individual cells, a view not easily obtained by other means. It is satisfying and often enlightening to be able to see the extremes as well as the average. In studies of the organization of karmellae, for example, ultrastructural analysis easily revealed the asymmetric segregation pattern, while immunoblots and cell fractionation could not even demonstrate the existence of this membrane organization. The richness of the information available to those who can avert reductionist tendencies, even for a short time, is remarkable.

Antithymocyte globulin hypersensitivity in bone marrow failure patients

We evaluated the predictive value of immediate epicutaneous (prick) skin testing in 36 patients receiving a heterologous protein of equine origin, antithymocyte globulin (ATG), for bone marrow failure. Three of the 36 patients had positive epicutaneous test results. Two of these three received ATG treatment; one died of anaphylaxis while the other was desensitized successfully. Intradermal skin tests revealed positive wheal-flare reactions to progressively increasing dilutions of ATG in 96% of patients tested. None of these patients suffered any anaphylactic symptoms during treatment. Nine patients who had received ATG were evaluated subsequently for the possible development of immediate epicutaneous reactions three to 12 months after treatment; one of the nine patients developed a positive epicutaneous skin test reaction. We recommend that all patients who are to be treated or re-treated with heterologous antisera should be tested using the epicutaneous technique and that patients with positive reactions should be desensitized.

Effect of endotoxin on release of reactive oxygen intermediates by rat hepatic macrophages

Reactive oxygen intermediates released by activated hepatic macrophages have been implicated in the pathogenesis of a rat model of liver injury induced by sequential administration of Corynebacterium parvum and endotoxin. In this model, C. parvum causes extensive infiltration of the liver with activated macrophages, but severe liver injury occurs only after subsequent exposure to endotoxin. We have therefore investigated the effects of endotoxin on the release of reactive oxygen intermediates by C. parvum-activated hepatic macrophages. After in vitro exposure to zymosan, opsonized zymosan, or phorbol myristate acetate, hepatic macrophages isolated from C. parvum- and endotoxin-treated rats demonstrated significantly (1.5-2-fold) increased release of superoxide and oxidation of [1-14C]glucose via the hexose monophosphate shunt compared with hepatic macrophages isolated from C. parvum- and saline-treated control rats. These results indicate that endotoxin enhances the state of activation of hepatic macrophages already partially activated by C. parvum. We suggest that the increased release of reactive oxygen intermediates by these cells promotes liver injury in this model.

Increased amounts of HMG-CoA reductase induce "karmellae": a proliferation of stacked membrane pairs surrounding the yeast nucleus

Overproduction of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in yeast resulted in striking morphological effects on the structure of intracellular membranes. Specifically, stacks of paired membranes closely associated with the nuclear envelope were observed in strains that over-produced the HMG1 isozyme, one of two isozymes for HMG-CoA reductase in yeast. These nuclear-associated, paired membranes have been named "karmellae." In strains that overproduced the HMG1 isozyme, HMG-CoA reductase was present in the karmellar layers. At mitosis, karmellae were asymmetrically segregated: the mother cells inherited all of the karmellae and the daughter cells inherited none. A membranous structure of different morphology was occasionally found in cells that overproduced the HMG2 isozyme. These observations further establish the existence of cellular mechanisms that monitor the levels of membrane proteins and compensate for changes in these levels by inducing synthesis of particular types of membrane.

Cold culture of different stage mouse embryos in bicarbonated and bicarbonate-free media

Mouse embryos of different stages of development were cultured to expanded blastocysts following storage (1 to 8 d) at 4 degrees C in the presence or absence of HCO(3)(-). The effect of oxygen tension on the cold storage of one- and two-cell mouse embryos at 4 degrees C was evaluated by 37 degrees C culture and transfer to pseudopregnant recipients. Survival at 4 degrees C of early, one- to four-cell mouse embryos was improved with HCO(3)(-) in the medium. The presence of HCO(3)(-) was not of benefit for morulae or blastocyst survival following cold storage. Reducing the oxygen atmosphere from 20 to 5% O(2) improved survival of one-cell mouse embryos stored at 4 degrees C. The survival of two- and four-cell embryos, morulae and blastocysts at 4 degrees C was similar in 90% N(2), 5% CO(2) and 5% CO(2) in air, but it was significantly poorer in air alone. The collapse of morulae and blastocysts during cold storage up to 5 d was reduced with HCO(3)(-) in the storage medium. Blastocysts stored for 6 d at 4 degrees C failed to survive following immediate transfer to pseudopregnant recipients. Blastocyst survival was improved compared to controls (direct transfer of unstored blastocysts to recipients) when cultured for 36 h at 37 degrees C following 6 d of cold storage. This result suggests that cold-stored mouse blastocysts may require a metabolic period of readjustment to survive following transfer to synchronized recipients.

Allergy and the chronic fatigue syndrome

The chronic fatigue syndrome is a heterogeneous disorder characterized by easy fatigability, feverishness, diffuse pains, and depression. Many patients also report inhalant, food, or drug allergies. This article reviews the clinical features of the syndrome and hypotheses of its pathogenesis, especially those regarding the Epstein-Barr virus and cellular immune mechanisms. Also summarized are recent studies of the validity of atopic complaints in the syndrome. The results of epicutaneous skin testing demonstrated a high correlation with history in 24 patients. Atopy coexists with the chronic fatigue syndrome in greater than 50% of patients.

The neglect of data-gathering instruments in behavior therapy practice

Although the Willoughby Personality Questionnaire and the Fear Survey Schedule are demonstrably valuable aids to the practice of behavior therapy of neurosis, it is evident that many behavior therapists do not use them. In order to determine the extent of their neglect, we sent a questionnaire to all Clinical Fellows of the Behavior Therapy and Research Society. The 134 replies we received revealed that the Willoughby was routinely used by only 19% and the Fear Survey Schedule by only 42%. This seems to be manifestation of a wide-spread but indefensible homogenized view of neuroses. It is a sad reflection on the quality of behavior therapy training programs.

Experience with a combined percutaneous and endoscopic approach to stent insertion in malignant obstructive jaundice

A non-operative method of palliation in malignant obstructive jaundice was used in 14 patients in whom a biliary stent could not be placed endoscopically. A guide wire was manipulated through the obstructing lesion through the percutaneous transhepatic route and retrieved through an endoscope. The stent was then fed through the endoscope over the guide wire and across the biliary stricture. There were no early complications, and worth-while palliation was obtained in most cases. The success rate for placing an endoscopic stent increased in this unit from 69 to 97% with the introduction of this technique.

Persistent measles virus genome in autoimmune chronic active hepatitis

A radiolabelled 50-base oligonucleotide complementary with the measles virus gene encoding the nucleocapsid was used as a probe to identify persistent measles virus genome in the lymphocytes from patients with autoimmune chronic active hepatitis (AICAH). Positive hybrids were found in 12 of 18 patients, and correlated strongly with high antibody titres to measles. Among the 45 controls, positive hybrids were found in 1 patient with measles, 1 of 3 patients with systemic lupus erythematosus, and 2 of 4 patients with cryptogenic cirrhosis. Persistence of part of the measles virus genome in AICAH may have important implications in the pathogenesis of the liver disease, and possibly in other disorders such as systemic lupus erythematosus, multiple sclerosis, and Paget's disease where an abnormal immune response to measles has been observed.

Food allergy and intolerance

In summary, there has been a dramatic increase in our understanding of food allergy as a result of research in immune mechanisms and clinical studies over the last decade. The subject has been comprehensively reviewed in a major new publication (Brostoff and Challacombe, 1986).