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V Johnson

Publications and source records attributed to V Johnson.

At least 73 records · Page 4Linked to original sources
PubMed1993

Treatment of Wilson's disease with zinc: XI. Interaction with other anticopper agents.

Zinc (Zn) is increasingly being used as a treatment for Wilson's disease. Some physicians have been prescribing Zn in conjunction with other anticopper agents, such as penicillamine or trien, although theoretically these drugs might be antagonistic in their effects. In addition, Wilson's disease patients quite often take vitamin C in high doses in conjunction with Zn therapy, and there are indications of possible interactions among vitamin C, Zn and copper (Cu). Interactions of penicillamine, trien, and vitamin C with Zn have not been previously studied in terms of the potential effects of these agents on Zn efficacy in Wilson's disease. Here we have studied these interactions in the maintenance phase of therapy, using Cu balance and absorption of orally administered 64Cu as endpoints. We find evidence for probable interactions of both penicillamine and trien with Zn; however, the end result on Cu balance is about the same with Zn alone as it is with Zn plus one of the other agents. Thus, there appear to be no advantages to concomitant administration. We find no detectable interaction of Zn and vitamin C on Cu balance, when vitamin C is taken in daily doses of 1000 mg.

Ascorbic Acid↗
PubMed1993

Does a vegetarian diet control Wilson's disease?

The literature indicates that copper (Cu) is less bioavailable from a vegetarian as compared to mixed diet. Further, several groups, including ours, find rather marginal average Cu intake in the typical American diet. For example, our data indicate that Wilson's disease patients on a typical American diet ingest only about 25% more Cu than is required. This suggests that a vegetarian diet, if it reduced bioavailability by about 25% or more, would be an adequate maintenance therapy for Wilson's disease. Observations in two of our patients, who were on lactovegetarian diets by choice, and who were almost totally noncompliant with anti-Cu therapy, support this view. These observations suggest that vegetarian diets may be a management tool for Wilson's disease. They also further emphasize the marginal Cu intake in American diets, and suggest that some seemingly healthy people, particularly vegetarians, may be at risk for mild Cu deficiency.

Acetates↗
PubMed1993

Treatment of Wilson's disease with zinc XII: dose regimen requirements.

A considerable body of data is now available indicating the efficacy and lack of toxicity of zinc treatment of Wilson's disease. Dose-response studies have shown that regimens of 50 mg of elemental zinc 3 times a day (50 mg x 3), 25 mg x 3, and 50 mg x 2 are effective, but 25 mg x 2 and 50 mg x 1 are not adequately effective. These studies indicate that 75 mg a day is close to the minimally effective dose, but do not address the question of necessary dose frequency. In the current study, the authors have used the minimally effective daily dose, 75 mg, and studied this daily dose in regimens of 25 mg x 3, 37.5 mg x 2, and 75 mg x 1 in treatment of four patients with Wilson's disease. These data have been supplemented with additional data from 11 patients treated with 25 mg 3 times a day and with data from 2 patients treated with 75 mg once a day. Efficacy was evaluated by 10-day copper balance and absorption of orally administered 64copper. The findings indicate that a daily dose of 75 mg must be divided into at least two doses to be effective, and that the 64copper procedure is more sensitive to zinc dose than copper balance.

Copper↗
PubMed1993

A longitudinal examination of the relationships among stress, coping strategies, and problems associated with alcohol use.

This study examined the longitudinal relationships among family history of alcoholism (FH+), stress levels, utilization of coping methods, and alcohol-related problems. Data used in this study were obtained from a nonclinical sample of subjects who were originally interviewed when they were 12, 15, or 18 years of age and followed-up twice more at 3-year intervals for a longitudinal sample size of 1270. Although a greater percentage of females in this sample reported a FH+ background as well as higher levels of stress, they tended to utilize positive coping strategies more often and reported fewer numbers of alcohol problems than males. In general, younger subjects who reported high levels of stress experienced more alcohol-related problems regardless of coping method chosen. In older subjects, the effect of stress on problems appeared to be buffered when coupled with the use of support seeking. Subjects whose stress preceded problems exhibited no significant difference from subjects whose problems preceded stress and symptom-free and "stressed-only" subjects were not significantly different from each other in number of problems at time 3, suggesting that a direct effect of stress alone on alcohol-related problems is questionable.

Adaptation, Psychological↗
PubMed1993

Effects of treatment on antibody titer to Porphyromonas gingivalis in gingival crevicular fluid of patients with rapidly progressive periodontitis.

Twenty-eight patients diagnosed as having rapidly progressive periodontitis (RPP) were enrolled in a study in which samples of subgingival microflora were harvested from test teeth and assayed for the presence of Porphyromonas gingivalis, and GCF collected and analyzed by ELISA for specific antibody for P. gingivalis. Clinical conditions were measured and recorded, and treatment by scaling and root planing provided at baseline and at 3, 6, 9, and 12 months. Reduction in pocket depth, stabilization of attachment level, and resolution of inflammation were comparable to previously reported values. By 3 months, mean and median specific antibody concentration had decreased, and continued to decrease through 12 months. The proportion of samples in which specific antibody was not detectable increased from 27% at baseline to 73% at month 12. GCF samples from sites at which P. gingivalis was present had greater than 2-fold higher median specific antibody than samples from P. gingivalis-negative sites. At baseline, specific antibody titer of 30-second GCF samples positively correlated with pocket depth, and GCF volume significantly correlated with antibody titer and concentration, and with pocket depth. In addition, change in specific antibody titer of 30-second samples from baseline to both 6 and 12 months correlated positively with pocket depths. Thus sites infected by P. gingivalis manifested high levels of specific antibody, and levels were related to clinical status. Following treatment, antibody levels decreased significantly as pocket depths decreased, attachment levels stabilized, and inflammation resolved.

Adult↗
PubMed1993

Primary team nursing: the 90s model.

The nursing shortage of the late 80s necessitated development of an alternative to primary nursing to meet patient needs. After assessing the strengths and limitations of functional nursing, team nursing and primary nursing, a team designed a new model which incorporated the best features of the three. After a pilot period, "primary team nursing" has proven effective and feedback from nurses has been positive.

Humans↗
PubMed1992

CT of 338 active professional boxers.

Computed tomography (CT) was performed in 338 active professional boxers. CT scans were abnormal in 25 boxers (7%). The most common CT abnormality was brain atrophy (22 cases). Focal lesions of low attenuation consistent with posttraumatic encephalomalacia were noted in only three boxers. Boxers with abnormal CT scans did not differ from those with borderline or normal CT scans in regard to age, win-loss record, number of bouts, or history of an abnormal electroencephalogram. Thirty-seven boxers with borderline CT scans (49%) and 17 with abnormal CT scans (68%) reported a previous technical knockout (TKO) or knockout (KO), compared with only 89 (37%) of the 238 boxers with normal CT scans (P < .01). Brain atrophy was noted more frequently in boxers with a large cavum septum pellucidum (CSP) than in those with a small or no CSP (P < .05). Boxers with abnormal or borderline CT scans who experienced a TKO or KO were slightly older than those with normal CT scans and a history of a TKO or KO (P < .05).

Adolescent↗
PubMed1992

Comprehensive restaging laparotomy in women with apparent early ovarian carcinoma.

OBJECTIVE: To determine the yield and morbidity of comprehensive restaging laparotomy in women with presumed early ovarian carcinoma who have undergone incomplete initial staging procedures. METHODS: We conducted a retrospective review of 30 women with apparent early ovarian carcinoma who underwent a comprehensive restaging laparotomy including multiple random intraperitoneal biopsies and selective pelvic/para-aortic lymphadenectomy before receiving adjuvant therapy. Positive findings were compared with clinicopathologic features. RESULTS: Only 17% of patients had adequate skin incisions, 53% had pelvic washings, and 37% had omental biopsy at primary surgery. Complications of restaging laparotomy included 53% severe adhesions, 20% bowel complications, and 20% vascular complications requiring suture. Nine patients (30%) had disease upstaged and six (20%) had stage III disease established by comprehensive restaging laparotomy. Two-thirds of the upstaged patients had occult metastases identified only through cytology, random peritoneal biopsies, or selective lymphadenectomy. Women with poorly differentiated or papillary serous lesions were more likely to have disease upstaged than those with well- and moderately differentiated lesions or other histologic types (P < .05). Other clinicopathologic features did not predict upstaging. CONCLUSION: A comprehensive staging laparotomy is needed to detect occult metastatic disease in women with apparent early ovarian carcinoma.

Adult↗
PubMed1991

Familial and personal drinking histories and measures of competence in youth.

Based on self-reported family histories, a sample of 1,270 adolescents were categorized into one of three groups: a) family history of alcoholism (FHA), b) family history of heavy drinking (FHHD), and c) family history symptom free (FHSF). These subjects were assessed on 26 measures tapping intra- and interpersonal competence at three points in time. Results of repeated measures (test time) ANOVAs revealed that FHA subjects (as compared to the two other groups) exhibited greatest levels of stress due to their inability to get along with others and the lowest level of attachment to their parents. Over the three test times, FHA subjects appeared to maintain an inappropriately low level of social orientation and display decreases in self-efficacy, goal directedness, and the level of trust and respect for their parents. Children of heavy-drinking, nonalcoholic parents also exhibited low levels of school achievement motivation and social orientation. The alcohol/drug use pattern of the subject was found to be associated with more measures of competence than was family drinking background. Examination of the relationship of varying levels of substance use and competence measures by age group revealed that deficits are not static during the span of adolescence through young adulthood.

Achievement↗
PubMed1991

Bayesian image processing in magnetic resonance imaging.

In the past several years, image processing techniques based on Bayesian models have received considerable attention. In our earlier work, we developed a novel Bayesian approach which was primarily aimed at the processing and reconstruction of images in positron emission tomography. In this paper, we describe how the technique has been adopted to process magnetic resonance images in order to reduce noise and artifacts, thereby improving image quality. In this framework, the image is assumed to be a statistical variable whose posterior probability density conditional on the observed image is modeled by the product of the likelihood function of the observed data with a prior density based our prior knowledge. A Gibbs random field incorporating local continuity information and with edge-detection capability is used as the prior model. Based on the formalism of the posterior density, we can compute an estimate of the image using an iterative technique. We have implemented this technique and applied it to phantom and clinical images. Our results indicate that the approach works reasonably well for reducing noise, enhancing edges, and removing ringing artifact.

Algorithms↗
PubMed1991

Experimental model of chronic global left ventricular dysfunction secondary to left coronary microembolization.

A model of chronic left ventricular dysfunction characterized by left ventricular dilation, elevated filling pressures and histologic changes has been lacking. In this study the use of coronary microsphere embolization-induced ischemia was explored as a method of producing chronic left ventricular dysfunction. Acute ischemic left ventricular dysfunction was induced in 13 mongrel dogs with 50 microns plastic microspheres until the peak positive first derivative of left ventricular pressure (dP/dt) decreased by 25% and the left ventricular end-diastolic pressure increased to greater than or equal to 12 mm Hg. After 8 weeks of observation, hemodynamic and echocardiographic variables were measured in each dog. Acute left ventricular dysfunction resulted in a dilated left ventricle with systolic dysfunction (area ejection fraction 24 +/- 6% vs. 57 +/- 9% initially, p less than 0.01) and elevated left ventricular filling pressures. Isovolumetric relaxation was prolonged and the peak rapid filling/atrial filling velocity and integral ratios were reduced. Eight weeks after embolization, there was an increased left ventricular size (end-diastolic area 15.1 +/- 2.1 cm2 at 8 weeks vs. 13.5 +/- 1.4 cm2 early after microsphere injection, p less than 0.05), unchanged end-systolic area, improved area ejection fraction and increased left ventricular mass. Left ventricular end-diastolic pressure increased and, despite continued abnormal relaxation, the peak rapid filling/atrial filling velocity and integral ratios increased to above baseline values, demonstrating a "restrictive" pattern. Gross and histologic examination revealed diffuse, patchy scarring associated with perivascular fibrosis. Thus, coronary microsphere embolization resulted in a model of chronic moderate left ventricular systolic dysfunction and abnormal diastolic function characterized by a "restrictive" filling pattern.

Animals↗
PubMed1991

Deep venous thrombosis in a child with nephrotic syndrome associated with a circulating anticoagulant and acquired protein S deficiency.

Thromboembolic events occur with a frequency of 3-5% in children with nephrotic syndrome (NS). Although numerous abnormalities in all phases of coagulation have been described in NS, the pathogenesis of clotting abnormalities remains poorly understood in this group of patients. We describe a child with long-standing NS in whom a severe deep venous thrombosis and pulmonary embolism secondary to acquired protein S deficiency and a strong lupus-type circulating anticoagulant developed. In addition, this patient had a markedly decreased plasma level of C4b binding protein. Although acquired protein S deficiency has been described in various clinical disorders including NS, our patient is unusual in having C4bBP deficiency, and his is the only reported pediatric case of NS complicated by thromboembolism in which a circulating anticoagulant has been implicated, to our knowledge.

Autoimmune Diseases↗
PubMed1991

Effects of the family environment on adolescent substance use, delinquency, and coping styles.

This study examines the overall and relative contributions of a variety of family environment measures to a child's alcohol, marijuana and other drug use, delinquent activity, and dysfunctional methods of coping with problems. The family environment variables tapped aspects of parental behaviors and attitudes, parenting styles, and family harmony and cohesion. Data were collected as part of a prospective, longitudinal study that examined the acquisition and maintenance of a variety of behaviors. Data were gleaned at two points in time, spanning 3-year intervals, from subjects ranging in age from early to late adolescence. In general, alcohol use among the younger subjects was more strongly determined by the use and attitudes of the same sex parent. In contrast, among older subjects, father's alcohol use was important to the offspring's use. While models predicting illicit drug use and the extent of problems related to alcohol and marijuana use fared least well, it was generally found that hostility and lack of warmth on the part of the parents contributed most to these outcomes in subjects. Finally, hostility displayed by both parents helped to determine the incidence of delinquency among sons and the use of dysfunctional coping methods among sons and daughters.

Adaptation, Psychological↗
PubMed1991

Diagnosis and characterization of presymptomatic patients with Wilson's disease and the use of molecular genetics to aid in the diagnosis.

Wilson's disease (WD) is an autosomal recessive disorder of copper accumulation leading to liver and/or brain damage. Although fatal if untreated, the condition can be treated effectively. Autosomal recessive inheritance indicates that siblings of affected patients are at 25% risk of having the disease. If they are diagnosed prior to becoming symptomatic, affected siblings can be kept free of symptoms by prophylactic therapy. In this paper we have examined the utility of copper-related variables, along with other clinical and molecular findings, in identifying those siblings of affected patients who should be further evaluated with a liver biopsy. Data are presented on a series of 13 presymptomatic patients in whom we have made the diagnosis of WD based on liver biopsy findings. Signs of liver disease were present in 12 out of 13 cases. The classic, noninvasive, screening approaches that we evaluated were not adequate to identify all cases of WD in this group of patients. These included positive Kayser-Fleischer (KF) rings, elevated liver serum alanine transferase, elevated urine copper, or elevated plasma nonceruloplasmin copper. We have introduced the use of molecular genetics for screening siblings of affected patients for WD. We show that a probe from the linked retinoblastoma (RB) gene can be very helpful in problem cases. However, at this time, the quantitative determination of liver copper concentration remains as the definitive diagnostic criterion.

Adolescent↗
PubMed1991

Treatment of Wilson's disease with zinc. IX: Response of serum lipids.

Zinc therapy in Wilson's disease is a lifelong treatment to prevent reaccumulation of copper. Previous reports have shown that in normal male subjects, zinc ingestion has reduced high-density lipoprotein cholesterol level. This finding raises the possibility that lifelong zinc therapy could be atherogenic. In the present work, the effects of zinc therapy on serum lipids over a period of years is evaluated in patients with Wilson's disease. Zinc therapy reduces total cholesterol level by about 10% in both sexes and reduces high-density lipoprotein cholesterol level by about 20% in male patients. The mechanisms of these interesting effects of zinc on cholesterol metabolism are unknown. The coronary heart disease risk factor is not changed significantly by zinc therapy in either sex, and further, it remains below average in these patients after zinc therapy. We conclude that zinc therapy in Wilson's disease is not atherogenic.

Cholesterol, HDL↗
PubMed1990

Effect of inotropic and vasodilator therapy on left ventricular diastolic filling in dogs with severe left ventricular dysfunction.

Inotropic and vasodilator therapy for congestive heart failure improve left ventricular systolic performance by different mechanisms. However, the nature and extent to which diastolic filling is altered have not been well described. Acute severe left ventricular dysfunction was induced in 21 dogs by severe left ventricular global ischemia produced by left main coronary artery microsphere embolization until left ventricular end-diastolic pressure was greater than or equal to 18 mm Hg. Dobutamine was infused in seven dogs until the peak positive first derivative of left ventricular pressure (dP/dt) increased by greater than or equal to 33%. Nitroprusside was infused in seven dogs until left ventricular end-diastolic pressure was less than 15 mm Hg. Seven dogs were observed for 1 h after the induction of acute severe left ventricular dysfunction and served as the control group. In all groups of dogs, severe left ventricular dysfunction resulted in left ventricular dilation, reduction in area ejection fraction, elevation of left ventricular end-diastolic pressure and an early redistribution of diastolic filling (increased 1/3 and 1/2 filling fractions) despite a markedly abnormal time constant of relaxation. No changes were noted in any variable after 1 h of observation in the seven control dogs. Nitroprusside reduced left ventricular size and filling pressure, increased cardiac output, improved relaxation and redistributed diastolic filling to later in diastole as characterized by a reduced 1/3 filling fraction (19.4 +/- 7.4% versus 51.4 +/- 10%, p less than 0.001). The pressure-area curve was shifted downward and leftward.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Risk factors of adolescent drug use: an affect-based interpretation.

We examined the continuity and stability of relational patterns among putative risk factors and measures of total drug use over the age period of 12 to 18. Using Marlatt's (1987) affect-based model of moderation versus dependence, risk factors were classified on the basis of their assumed relationships to (a) positive and negative affect and (b) low versus high constraint. It was hypothesized that two distinct developmental pathways characterize the emergence of drug use in a normal population sample of adolescents: one indicative of low constraint and a predominance of positive affect, the other indicative of low constraint and a predominance of negative affect. Results of principal components analyses generally support the hypothesis. Theoretical and methodological implications are discussed.

Adolescent↗