A new suction device for microsurgery

A new suction device for microsurgical procedures is presented. This device is made of soft, compliant PVC, which enables all fluids to be evacuated from the surgical field without damaging the surrounding soft tissue. The device is designed with front and radial ports that allow placement onto the blood vessel or nerve while the anastomosis is being performed. There is a tapered end providing the surgeon with fine control of the suction. Unlike other bulky suction devices, this one readily fits into the operative field without inhibiting operative procedures. It also readily fits varying sizes of conventional Frazier-type tips. The device has been used in over 100 microsurgical procedures and it has served well.     

Evolution of the organization of epicardial activation patterns during ventricular fibrillation

INTRODUCTION: This study quantified how the organization of epicardial activation changes during the first 40 seconds of ventricular fibrillation (VF). METHODS AND RESULTS: Unipolar potentials were mapped from a 504 (24 x 21) electrode array (2-mm interelectrode spacing) on the anterior right ventricle (RV) and left ventricle (LV) epicardium. The array covered approximately 20% of the epicardial surface. In each of seven pigs, six episodes of VF were induced by premature stimulation. One-half second epochs of VF were analyzed, starting 0, 10, 20, 30, and 40 seconds post induction and using novel pattern analysis algorithms. Eight parameters were quantified: (1) the number of wavefronts; (2) the epicardial area activated by wavefronts; (3) the fraction of wavefronts arising from epicardial breakthrough or from a focus; (4) the fraction of wavefronts terminated by conduction block; (5) the multiplicity index (number of distinct activation pathways in the rhythm); (6) the repeatability index (number of times activation pathways are traversed); (7) the activation rate; and (8) the wavefront propagation velocity. The results showed that VF patterns were less organized at 10 than at 0 seconds, with more, smaller wavefronts traversing a larger variety of pathways for fewer repetitions. VF activation patterns then gradually reorganized up to 40 seconds, but by a different mechanism: the spatial size of subpatterns grew, but the dynamics otherwise appeared unchanged. During both transitions, both activation rate and propagation velocity slowed monotonically. CONCLUSION: Thus, changes in organization during VF can occur by multiple mechanisms.     

Angioplasty and primary stenting of the subclavian, innominate, and common carotid arteries in 83 patients

A new macrocyclic of the bis(benzylisoquinoline) alkaloid family, d-(+)-tubocurarine chloride (DTC), has been evaluated as a chiral selector for the separation of optical isomers of organic carboxylates using capillary electrophoresis (CE). The pertinent physicochemical properties, such as absorption spectrum, isoionic point, and solution conformation, of DTC were determined. The effects of varying such experimental parameters as DTC concentration, pH, and methanol content in the running buffer were assessed. CE separation of the enantiomers of 18 different compounds was achieved using DTC as the chiral selector under optimized background electrolytic conditions.     

Immunological and virological analyses of persons infected by human immunodeficiency virus type 1 while participating in trials of recombinant gp120 subunit vaccines

We have studied 18 participants in phase I/II clinical trials of recombinant gp120 (rgp120) subunit vaccines (MN and SF-2) who became infected with human immunodeficiency virus type 1 (HIV-1) during the course of the trials. Of the 18 individuals, 2 had received a placebo vaccine, 9 had been immunized with MN rgp120, and seven had been immunized with SF-2 rgp120. Thirteen of the 18 infected vaccinees had received three or four immunizations prior to becoming infected. Of these, two were placebo recipients, six had received MN rgp120, and five had received SF-2 rgp120. Only 1 of the 11 rgp120 recipients who had multiple immunizations failed to develop a strong immunoglobulin G antibody response to the immunogen. However, the antibody response to rgp120 was transient, typically having a half-life of 40 to 60 days. No significant neutralizing activity against the infecting strain was detected in any of the infected individuals at any time prior to infection. Antibody titers in subjects infected despite vaccination and in noninfected subjects were not significantly different. Envelope-specific cytotoxic T-lymphocyte responses measured after infection were infrequent and weak in the nine vaccinees who were tested. HIV-1 was isolated successfully from all 18 individuals. Sixteen of these strains had a non-syncytium-inducing (NSI) phenotype, while two had a syncytium-inducing (SI) phenotype. NSI strains used the CCR5 coreceptor to enter CD4+ cells, while an SI strain from one of the vaccinees also used CXCR4. Viruses isolated from the blood of rgp120 vaccinees were indistinguishable from viruses isolated from control individuals in terms of their inherent sensitivity to neutralization by specific monoclonal antibodies and their replication rates in vitro. Furthermore, genetic sequencing of the env genes of strains infecting the vaccinees did not reveal any features that clearly distinguished these viruses from contemporary clade B viruses circulating in the United States. Thus, despite rigorous genetic analyses, using various breakdowns of the data sets, we could find no evidence that rgp120 vaccination exerted selection pressure on the infecting HIV-1 strains. The viral burdens in the infected rgp120 vaccine recipients were also determined, and they were found to be not significantly different from those in cohorts of placebo-vaccinated and nonvaccinated individuals. In summary, we conclude that vaccination with rgp120 has had,to date, no obvious beneficial or adverse effects on the individuals we have studied.     

Metabolic routing towards polyhydroxyalkanoic acid synthesis in recombinant Escherichia coli (fadR): inhibition of fatty acid beta-oxidation by acrylic acid

We have systematically isolated and characterized DNA containing large CTG (n > 7) repeats from a human cosmid genomic DNA library. Using a CTG10 probe, more than 100 cosmid clones were identified, and 30 of these have been extensively characterized. The sequenced cosmids contain repeats that are between three and 19 perfect units (average 10 perfect repeats). The cosmids map to at least 12 different chromosomes. Sequence analysis of flanking regions suggests that more than one third of the repeats occur in exons, and many share strong sequence identity with databank sequences, including the gene involved in dentatorubral pallidoluysian atrophy (DRPLA). Genotyping of human DNA samples demonstrates that more than half of the repeats are polymorphic. This and similar collections of clones containing trinucleotide repeats should aid in the identification of genes that may contain expansions of trinucleotide repeats involved in human disease.     

CHESS: comprehensive health enhancement support system for women with breast cancer

The Comprehensive Health Enhancement Support System (CHESS) was developed to assist people dealing with health crises. Needs assessments with patients were conducted in its development and validation studies performed. CHESS provides information, social support, and decision-making assistance via a personal computer and modem that are placed in patients' homes. Women of all ages and varied socioeconomic backgrounds have successfully used this program to empower them to become active participants in their care following a diagnosis of breast cancer.     

Effects of subchronic administration of metrifonate on cholinergic neurotransmission in rats

The effects of subchronic oral administration of metrifonate, a long-acting cholinesterase (ChE) inhibitor, on cholinergic neurotransmission were assessed in young adult male Wistar rats. Animals were treated twice daily with metrifonate. In a pilot study testing a 100 mg/kg dose of metrifonate for up to 14 days, ChE activity was found to steadily decrease to reach maximum inhibition levels of about 55%, 80% and 35% in brain, erythrocytes and plasma. Steady-state inhibition levels were attained by the 10th day of treatment. When metrifonate-treatment was discontinued, ChE activity in plasma returned to control levels within another day, while erythrocyte and brain ChE activity took more than 2 weeks to recover. In subsequent dose-response studies, metrifonate treatment was given for 3 and 4.5 weeks at doses of 0, 12.5, 25, 50, and 100 mg/kg, to different groups of animals, respectively. Correlation analysis indicted that brain ChE inhibition was more accurately reflected by erythrocyte than by plasma ChE inhibition, although all effects were highly correlated. The changes in ChE activity were not paralleled by changes in other parameters of the cholinergic neurotransmission, such as acetylcholine synthesis rate or acetylcholine receptor binding. It is therefore concluded that repeated administration of metrifonate to rats induces a long-lasting inhibition of ChE activity in a dose-related and predictable manner, which is neither subject to desensitization nor paralleled by counterregulatory downregulation of muscarinic or nicotinic receptor binding sites in brain.     

Salivary PAF in acute myocardial infarction and angina: changes during hospital treatment and relationship to cardiac enzymes

Salivary levels of platelet activating factor (PAF) were measured together with serum CPK and interleukin 2 receptor in 30 patients admitted to the coronary care unit, 9 patients with pulmonary tuberculosis, 10 with acute severe asthma and 8 normal controls. 16 of the 30 C.C.U. patients had sustained a acute myocardial infarction (M.I.) 5 had acute angina and the remaining 9 had non cardiac chest pain. Salivary PAF on admission was significantly higher in the M.I. Patients than in the normal subjects, asthmatics, tuberculosis patients and those with non cardiac chest pain (p < 0.001 in all cases) but not those with angina. After 48 hours PAF levels fell in the subjects with M.I. (p < 0.01) and no significant difference was seen between any group. PAF levels did not show any relationship with CPK levels or site of infarct in the M.I. patients. Interleukin 2 receptor was not significantly raised in the M.I. group as a whole but some individual patients showed markedly increased serum levels, but these levels did not correlate with either salivary PAF or serum CPK.     

Network management as a strategy

Teleprocessing users require reliability, which implies network control and diagnosis. Three levels of control are identified and described: technical control, network control and network management. The advantages of the latter are discussed in terms of an integrated design strategy.     

Varicella-zoster virus: infection, control, and prevention

Varicella-zoster virus is a herpes virus that produces a primary infection, chickenpox, manifested by a vesicular eruption and is considered one of the common childhood infectious diseases. After the initial infection the virus becomes latent, then when activated it is manifested as herpes zoster, commonly known as shingles. This highly communicable human disease is associated with serious morbidity and significant mortality, particularly among the immunocompromised. When introduced in the hospital, significant disruptions occur and serious sequelae may results. Recently, a live virus varicella vaccine was approved by the Food and Drug Administration in the United States. Studies have shown the vaccine to be safe and effective. Widespread use of this vaccine may be beneficial in reducing the opportunities for varicella-zoster virus introductions in health care settings.