Showing papers by "University of Medicine and Dentistry of New Jersey published in 1988"

Scale for suicide ideation: Psychometric properties of a self-report version

Abstract: A self-report version of the Scale for Suicide Ideation (SSI) was administered to 50 inpatients diagnosed with mixed DSM-III psychiatric disorders and 55 outpatients with affective disorders. The self-report SSI was written for both paper-and-pencil and computer administration. The correlations between the self-reported and clinically rated versions for both inpatients and outpatients were greater than .90, which suggests strong concurrent validity. The Cronbach coefficient alphas for the paper-and-pencil and computer versions were also in the .90s and indicated high internal consistency. Furthermore, the mean SSI scores of the computer version for both the inpatients and outpatients were higher than the mean SSI scores of the clinical ratings; the patients described more severe suicide ideation than clinicians reported.

Occupational stress among health care workers: A test of the job demands-control model

Abstract: Models of occupational stress have often failed to make explicit the variable of control over the environment, as well as the role of job socialization in shaping personality characteristics and coping behaviours. This neglect has helped maintain the focus of stress reduction interventions on the individual. A new model of occupational stress developed by Robert Karasek incorporates control and socialization effects and has successfully predicted the development of heart disease and psychological strain. A survey instrument derived from the model was distributed to 771 hospital and nursing home employees in New Jersey, and 289 (37.5 per cent) were returned. Respondents did not significantly differ from non-respondents by age, sex, job tenure, union membership status, job satisfaction, job perceptions and attitude towards employer and union. The results support the hypothesis that reported job strain (job dissatisfaction, depression, psychosomatic symptoms) and burnout is significantly higher in jobs that combine high workload demands with low decision latitude. This association remained significant after controlling for age, sex, education, marital status, children, hours worked per week and shift worked. Other job characteristics (job insecurity, physical exertion, social support, hazard exposure) were also associated with strain and burnout. The survey instrument also identified high strain jobtitles in the surveyed workplaces. The results are discussed in relation to directions for future research, research on stress in nursing, and approaches to stress reduction.

Collagen type I and type V are present in the same fibril in the avian corneal stroma.

Abstract: The distribution, supramolecular form, and arrangement of collagen types I and V in the chicken embryo corneal stroma were studied using electron microscopy, collagen type-specific monoclonal antibodies, and a preembedding immunogold method. Double-label immunoelectron microscopy with colloidal gold-tagged monoclonal antibodies was used to simultaneously localize collagen type I and type V within the chick corneal stroma. The results definitively demonstrate, for the first time, that both collagens are codistributed within the same fibril. Type I collagen was localized to striated fibrils throughout the corneal stroma homogeneously. Type V collagen could be localized only after pretreatment of the tissue to partially disrupt collagen fibril structure. After such pretreatments the type V collagen was found in regions where fibrils were partially dissociated and not in regions where fibril structure was intact. When pretreated tissues were double labeled with antibodies against types I and V collagen coupled to different size gold particles, the two collagens colocalized in areas where fibril structure was partially disrupted. Antibodies against type IV collagen were used as a control and were nonreactive with fibrils. These results indicate that collagen types I and V are assembled together within single fibrils in the corneal stroma such that the interaction of these collagen types within heterotypic fibrils masks the epitopes on the type V collagen molecule. One consequence of the formation of such heterotypic fibrils may be the regulation of corneal fibril diameter, a condition essential for corneal transparency.

Drug bonded prosthesis and process for producing same

Abstract: There is disclosed an improved prosthesis coated, respectively, with an anionic surfactant, a drug such as an antibiotic and/or antithrombotic agent. Optionally, the coated prosthesis may be treated with an ion exchange compound, to remove un-drug bound anionic surfactant. The drug is bound directly to the surfactant coated prosthesis.

New Jersey Low Contact Stress Total Ankle Replacement: Biomechanical Rationale and Review of 23 Cementless Cases

Abstract: A congruent contact, unconstrained, multiaxial ankle replacement has been developed for use without cement. A talar onlay component with a trochlear surface and central fixation fin uses a cylindrical articulating axis that reproduces the lateral talar curvature. A tibial inlay component with a 7 degree anteriorly inclined short fixation stem uses a flat loading plate, recessed anatomically into the distal tibia to distribute tibial loads to the ankle joint. For both components, made of cast cobalt-chromium-molybdenum, a 275-micron pore-size, sintered-bead, porous coating is used to allow tissue ingrowth stabilization. A congruent ultra-high molecular weight polyethylene bearing is inserted between the metallic implants. Its upper surface is flat, whereas its lower surface conforms to the trochlear surface, thereby providing unconstrained, sliding cylindrical motion with low contact stress on the bearing surfaces. Contact pressure and collateral ligaments maintain ankle stability during both static and dynamic loading conditions. Clinically, 23 total ankle arthroplasties were performed in 21 patients. The follow-up period ranged from 24 months to 64 months with a mean of 35.3 months. Diagnoses included rheumatoid arthritis, 6 patients (26.1%); osteoarthritis, 4 patients (17.4%); post-traumatic arthritis, 10 patients (43.5%); avascular necrosis of the talus, 2 patients (8.7%), and painful ankle fusion, 1 patient (4.3%). Pain was the primary reason for surgery in all cases. Postoperatively, 87% of ankles had no pain or, at most, mild pain. Postoperative complications included poor wound healing in four ankles, reflex sympathetic dystrophy in two ankles, deep infection in one ankle, and one bearing subluxation. No ankle replacements were removed and no fusions were performed for failed implants, although one bearing was exchanged without disrupting the metallic elements. In this report, the suggestion is made that total ankle arthroplasty may have an improved application in various arthritis disorders when used with biologic fixation and unconstrained mobile bearings.

Vascular and neural invasion in colorectal carcinoma. Incidence and prognostic significance.

Abstract: The incidence and significance of histologic vascular and/or neural invasion in 77 patients with colorectal carcinoma treated over a 6-year period were analyzed retrospectively Vascular invasion was found in 376% of patients and neural invasion in 143% The following three types of vascular invasion were identified: tumor lining epithelium, tumor thrombi, and destruction of the vessel wall The incidence of metastases in patients with vascular invasion was 60% as opposed to 17% in those without vascular invasions (P less than 00001) Survival in these patients was 297% and 622%, respectively (P less than 0003) Metastases were found in 727% of patients with neural invasion, as opposed to 27% of those without neural invasion (P less than 001) Survival was 296% as opposed to 577% in those without neural invasion (P less than 0003) Even among patients in the same Dukes' stage, prognosis, as determined by incidence of recurrence, metastases, and survival, was worse significantly among those patients demonstrating vascular invasion (P less than 003) Examination of patients with colorectal carcinoma for the presence of vascular and neural invasion may provide useful information for determining future treatment and prognosis

A double-blind randomized crossover trial of bromocriptine and placebo in restless legs syndrome.

Abstract: A double-blind randomized crossover study of 7.5 mg bromocriptine at bedtime versus placebo was conducted in 30-day phases (with a 2-week washout period between phases) in 6 patients with idiopathic restless legs syndrome. Five patients experienced partial subjective improvement in restlessness and paresthesias on bromocriptine as opposed to placebo and expressed a desire to continue on the medication. On bromocriptine, the patients showed polysomnographically a mean Decemberrease of 43% from control and a mean Decemberrease of 57% from placebo in the number of periodic movements of sleep per hour of sleep (p < 0.025). Two of 3 patients with abnormally Decemberreased total sleep time and sleep efficiency showed an improvement in these measures on therapy. The dopamine agonist bromocriptine may be a useful therapy in some patients with restless legs syndrome.

Effect of Diallyl Sulfide on Rat Liver Microsomal Nitrosamine Metabolism and Other Monooxygenase Activities

Abstract: It has been reported that p.o. administration of diallyl sulfide (DAS), a naturally occurring component of garlic (Allium sativum), inhibits 1,2-dimethylhydrazine-induced colon and liver cancer in rodents. A possible mechanism for this protective effect is inhibition of hepatic activation of the procarcinogen. The effect of DAS on P450IIE1, an isozyme of cytochrome P-450 which is active in the oxidative metabolism of dimethylhydrazine, was conveniently assayed in the present study by determination of N-dimethylnitrosamine demethylase (NDMAd) activity at 1 mM N-dimethylnitrosamine in Sprague-Dawley rat liver microsomal incubations. DAS was found to be a competitive inhibitor of NDMAd, in contrast to the irreversible inactivation of NDMAd produced by carbon tetrachloride incubated under similar conditions. The inhibition by DAS of the demethylation of several substrates was selective. The thioether was most potent against N-dimethylnitrosamine, less effective against N-nitrosomethylbenzylamine, and essentially ineffective against benzphetamine and ethylmorphine. Microsomes prepared at 3 h after DAS administration (200 mg/kg in corn oil intragastrically) showed moderate inhibition (less than 30% inhibition compared to control microsomes) of several demethylase activities; however, microsomes prepared 18 h posttreatment showed a marked decrease (about 80% inhibition compared to controls) in NDMAd activity, minor effects on other demethylase activities, and a 6-fold increase in pentoxyresorufin dealkylation. These trends at 18 h agreed with immunoblot analyses which showed suppression in the level of P450IIE1 and an elevation in P450IIB1. The selective inhibition of P450IIE1 activity and suppression of its level in microsomes may contribute to the reported chemoprotective effects of DAS.

The changing character of the medical profession: a theoretical overview.

Abstract: Technological advances in medicine have greatly enhanced the ability of physicians to treat disease and disability, but, at the same time, changes in the organization and management of health care services in the United States have imposed constraints on their autonomy. How have these changes--medical advancement and professional decline--affected the theoretical concept of the medical profession? Challenging the prevailing model of professional dominance, the concepts of deprofessionalization, corporatization, and proletarianization emphasize the effects of recent social and economic developments on the changing status of the medical profession. There is evidence, however, that what the proponents of these concepts perceive as the profession's response to external forces are, in fact, the unanticipated consequences of the profession's campaign for autonomy.

The precursor of a metalloendopeptidase from human rheumatoid synovial fibroblasts. Purification and mechanisms of activation by endopeptidases and 4-aminophenylmercuric acetate.

Abstract: Two active forms (Mr 45,000 and 28,000) of a metalloendopeptidase that digest proteoglycans and other extracellular matrix components of connective tissues have previously been purified from rheumatoid synovial cells and characterized [Okada, Nagase & Harris (1986) J. Biol. Chem. 261, 14245-14255]. To study the mechanisms of activation the precursor of this metalloendopeptidase has now been purified. The final products are homogeneous on SDS/polyacrylamide-gel electrophoresis and identified as a set of zymogens of Mr 57,000 and 59,000, in which the latter form is probably the product of post-translational glycosylation of the Mr 57,000 zymogen, as it binds to concanavalin A. The zymogen can be activated by trypsin, chymotrypsin, plasma kallikrein, plasmin and thermolysin, but not by thrombin. Although the activated metalloendopeptidase is further degraded by trypsin, plasma kallikrein and thermolysin during a prolonged incubation, it is relatively stable against plasmin and chymotrypsin. Activation with 4-aminophenylmercuric acetate is dependent on its concentration. It requires the reaction with the zymogen, possibly through thiol groups, and the continued presence of the agent. During this treatment the zymogen undergoes a sequential processing; first it becomes active without changing its apparent molecular mass, and then it is processed to low-Mr species of Mr 46,000, 45,000 (HMM) and 28,000 (LMM). The rate of conversion of the precursor into an initial intermediate of Mr 46,000 follows first-order kinetics (t1/2 2.0 h with 1.5 mM-4-amino-phenylmercuric acetate at 37 degrees C) and is independent of the initial concentration of the zymogen or the presence of up to a 676-fold molar excess of substrate, whereas the generation of HMM and LMM species is affected by these parameters. These results indicate that activation of the prometalloendopeptidase by an organomercurial compound is initiated by the molecular perturbation of the zymogen that results in conversion into the 46,000-Mr intermediate by an intramolecular action; the subsequent processing of this intermediate in HMM and LMM species is a bimolecular reaction. In vivo it is probable that the precursor of this metalloendopeptidase is activated either by direct limited proteolysis by tissue or plasma endopeptidases, or, alternatively, by factors that cause certain conformational changes in the zymogen molecule.

Septic thrombosis of the cavernous sinuses.

Abstract: • Cavernous sinus thrombosis may occur as a complication of infectious and noninfectious processes. Septic thrombosis of the cavernous sinuses most commonly follows infections of the middle third of the face due to Staphylococcus aureus . Other antecedent sites of infection include paranasal (usually sphenoid) sinusitis, dental abscess and, less often, otitis media. Fever is a nearly constant finding, but headache may not be prominent. Periorbital edema, chemosis, proptosis, and limitation of extraocular movements (especially lateral gaze) develop in almost all recognized cases. Involvement of the opposite eye frequently appears within two days following the onset of unilateral signs. Although computed tomography may be helpful, magnetic resonance imaging is probably the diagnostic procedure of choice. Treatment includes appropriate antibiotics and, oftentimes, surgical drainage of the primary focus of infection. Less than half of the patients recover completely; the mortality rate is approximately 30%.

Frequent Rehospitalization and Noncompliance With Treatment

Abstract: The relationship between frequent rehospitalization and compliance with treatment (medication and aftercare) was examined in a retrospective chart review of patients treated at an urban community mental health center over an 18-month period. Twenty-five patients who had been hospitalized three or more times during the study period were compared with a matched group of 25 patients who had been bospi talized less than three times and with the total group of 698 patients active at the center through out that period. The study found a highly significant correlation between noncompliance with medication and frequent rehospitalization. Compared with the general psychiatric patient population, frequently hospitalized patients tended to be younger and to have a chronic psychiatric illness, particularly one with an affective component, that featured at least intermittent psychosis. The author recommends study of outpatient commitment to treatment as a means of reducing noncompliance.

Metabolism of N-Nitrosodialkylamines by Human Liver Microsomes

Abstract: The metabolism of N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine, N-nitrosobenzylmethylamine, and N-nitrosobutylmethylamine was investigated in incubations with human liver microsomes. All of the 16 microsomal samples studied were able to oxidize NDMA to both formaldehyde and nitrite at NDMA concentrations as low as 0.2 mM; the rates of product formation of the samples ranged from 0.18 to 2.99 nmol formaldehyde/min/mg microsomal protein (median, 0.53 nmol). At a concentration of 0.2 mM NDMA, the rates of denitrosation (nitrite formation) were 5 to 10% (median, 6.3%) those of demethylation (formaldehyde formation); the ratio of denitrosation to demethylation increased with increases in NDMA concentration, in a similar manner to rat liver microsomes. Immunoblot analysis with antibodies prepared against rat P-450ac (an acetone-inducible form of cytochrome P-450) indicated that the P-450ac [P-450j (isoniazid-inducible form)] orthologue in human liver microsomes had a slightly higher molecular weight than rat P-450ac and the amounts of P-450ac orthologue in human liver microsomes were highly correlated with NDMA demethylase activities (r = 0.971; P less than 0.001). Analysis of four selected microsomal samples showed that human liver microsomes exhibited at least three apparent Km and corresponding Vmax values for NDMA demethylase. This result, suggesting the metabolism of NDMA by different P-450 enzymes, is similar to that obtained with rat liver microsomes, even though most of the human samples had lower activities than did the rat liver microsomes. The high affinity Km values of the four human samples ranged from 27 to 48 microM (median, 35 microM), which were similar to or slightly lower than those observed in rat liver microsomes, indicating that human liver microsomes are as efficient as rat liver microsomes in the metabolism of NDMA. The human liver microsomes also catalyzed the dealkylation and denitrosation of other nitrosamines examined. The rates of product formation and the ratios of denitrosation to dealkylation varied with the structures and concentrations of the substrates as well as with the microsomal samples tested. The results indicate that human liver microsomes are capable of metabolizing N-nitrosodialkylamines via the pathways that have been established with rat liver microsomes.

Deprenyl in the Treatment of Symptom Fluctuations in Advanced Parkinson's Disease

Abstract: Deprenyl, a selective inhibitor of monoamine oxidase, type B, which is free of the "tyramine effect," may ameliorate symptom fluctuations in advanced Parkinson's disease (PD). We randomized 96 patients with marked symptom fluctuations at three centers to receive either deprenyl 5 mg b.i.d. or placebo in parallel fashion in addition to a previously optimized levodopa/carbidopa (Sinemet) regimen. Disability was recorded hourly at home by patients 3 days weekly during the 2-week baseline and the 6-week treatment period. Disability during the "on" state was assessed each week by examination. Mean hourly self-assessment of gait improved in 28 of 50 patients (56%) receiving deprenyl (mean degree of improvement 0.25 points on a 0-2 scale) and in 14 of 46 (30.4%) taking placebo (mean 0.15). Mean hourly overall symptom control improved in 29 (58%) taking deprenyl (mean 0.34) and in 12 (26.1%) taking placebo (mean 0.15) (p less than 0.01 for each parameter). No significant improvement occurred in the objective quality of the "on" state with deprenyl. Mean daily Sinemet dosage decreases were 17% in the deprenyl group and 7% in the placebo group. Adverse effects included nausea, light-headedness, dyskinesias, and hallucinations, all of which abated after the Sinemet dose was reduced. We conclude that deprenyl is of moderate benefit in a majority of patients with symptom fluctuations complicating PD and is generally well tolerated.

Case-control study of early life dietary factors in Parkinson's disease.

Abstract: • Studies of the amyotrophic lateral sclerosis parkinsonism dementia complex of Guam direct suspicion to a heat-labile component of vegetables found in greatest concentration in seeds. We therefore surveyed patients with Parkinson's disease (PD) regarding early adult consumption of fruits and vegetables usually eaten raw, with seeds that are swallowed or scraped with the teeth. We administered a pretested questionnaire by telephone to 81 nondemented patients with PD and to a same-sex married sibling without PD. The patients and their siblings were asked whether they or their spouse (as an internal standard) had been more likely to eat each of 17 food items between marrying and age 40 years. No item was associated with the presence of PD. Unexpectedly associated with the absence of PD were preference for nuts (odds ratio, 0.39), salad oil or dressing (pressed from seeds) (odds ratio, 0.30), and plums (odds ratio, 0.24). These three items have higher vitamin E content than the other 14 items in our questionnaire. Our data are consistent with the hypothesis that vitamin E, as an antioxidant, may have prophylactic value against PD.

"Sandwich"-type immunoassay of carcinoembryonic antigen in patients receiving murine monoclonal antibodies for diagnosis and therapy.

Abstract: Measurements of carcinoembryonic antigen (CEA) in blood increased dramatically in some patients who were receiving injections of monoclonal antibody. CEA titers were measured with a monoclonal antibody-based double-determinant enzyme immunoassay in which untreated plasma specimens were diluted with an equal volume of buffer containing mouse serum. Increasing CEA titers were accompanied by the appearance and coincident increase in titers of human antibody against mouse Ig (HAMA). Adsorption of these sera with solid-phase anti-human IgG or Protein A restored antigen titers to pretreatment values; evidently the serum factor eliciting false-positive CEA titers was most probably HAMA. Neither addition of undiluted mouse serum to the assay mixture nor pretreatment by heating plasma specimens to 70 degrees C effectively abolished HAMA interference. By contrast, protein precipitation with polyethylene glycol (130 g/L) or heating plasma samples to 90 degrees C eliminated false-positive titers caused by HAMA, but did not reduce authentic CEA titers.