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Biomedical subjects

S Johnson

Publications and source records attributed to S Johnson.

At least 649 records · Page 36Linked to original sources
PubMedDate not supplied

Proximal gastric vagotomy by minimally invasive methods in an acute rat model.

In this prospective study, minimally invasive methods of proximal gastric vagotomy (PGV) were investigated in male Sprague-Dawley rats. Completeness of vagotomy by traditional operative therapy, by laser denervation of the gastric serosa, and by subserosal or transmucosal injections of chemoneurolytic agents was evaluated with postoperative Congo red testing, ulcerogenic stimulation of the gastric mucosa, and histochemical labeling of whatever vagal fibers remained in the gastric wall. Short-term results demonstrate that successful PGV can be performed with minimally invasive methods.

Animals↗
PubMedDate not supplied

Timing of laparoscopic cholecystectomy in acute cholecystitis.

BACKGROUND: Laparoscopic cholecystectomy is associated with an increased conversion rate in acute cholecystitis. AIM: To review the operative management of symptomatic cholelithiasis with particular reference to conversion rates and morbidity for laparoscopic cholecystectomy for acute cholecystitis. METHODS: Patients undergoing cholecystectomy between January 1994 and December 1998 were recruited. Demographic details, diagnosis, duration of symptoms, treatment, outcome, post-operative stay and complications were recorded. RESULTS: Complete data were available on 482 patients (84%). Laparoscopic cholecystectomy was attempted in 120 of 132 patients (91%) with acute cholecystitis and 329 of 350 patients (94%) with non-acute gallbladder disease. Conversion rates were 27% (33/120) and 6.7% (22/329) for acute and non-acute gallbladder disease, respectively (p < 0.001 chi2 test). Relating the interval from onset of symptoms to surgery, conversion rates for acute cholecystitis were: < 3 days, 5/17 (29%); 4 to 42 days, 14/59 (23%) and > 42 days, 14/44 (31%). There were three bile duct injuries, two in the delayed (> 45 days) acute group and one in the non-acute group. CONCLUSION: Early laparoscopic cholecystectomy is the treatment of choice for acute cholecystitis, but is associated with a high conversion rate independent of the timing of surgery.

Cholecystectomy, Laparoscopic↗
PubMedDate not supplied

Observations of subacute sclerosing panencephalitis in South Africa.

Analysis of 75 cases of subacute sclerosing panencephalitis (SSPE) reported to the National Institute for Virology, South Africa, in 1984-1990 does not support the role of intensive exposure to measles virus in the pathogenesis of SSPE. The incidence of SSPE per million population was similar in Blacks and Whites, although that of reported measles is up to 10 times greater in Blacks. The age of SSPE follows the distribution of measles cases; thus, significantly more younger SSPE cases were found in Blacks than in Whites. The distribution between males and females was approximately equal. These data suggest SSPE to be a fortuitous complication of measles infection associated with as yet unidentified risk factors rather than a consequence of an excessive dose of infecting virus or immunological immaturity.

Adolescent↗
PubMedDate not supplied

The role of sexual transmission in the epidemiology of hepatitis C virus in black South Africans.

The role of sexual transmission of hepatitis C virus in Black South Africans was evaluated by a seroprevalence study of sentinel populations at varying risk for sexually transmitted diseases (STD). Prevalence of anti-hepatitis C virus antibodies was found to be 1.8% in an STD clinic sample of 272, 0.7% in a family planning sample of 148, 3.3% in a sample of 246 'blue collar' workers (81% of rural origin), and 0.9 in a sample of 117 new blood donors. All samples were from Black adults. The differences between them were not significant (P = 0.2348). In contrast, the prevalence of anti-human immunodeficiency virus antibodies in the STD sample (5.5%) was statistically significantly different (P = 0.00095) from the family planning clinic sample (1.4%) and the blue collar sample (0.8%) as well as from the reported prevalence for black blood donors in the Johannesburg area (0.7%). No evidence supporting a role for sexual transmission of hepatitis C virus was found, while the prevalence of infection appeared to be higher in rural populations and in males. These features are similar to hepatitis B in this population.

Adolescent↗
PubMedDate not supplied

Poliomyelitis outbreak in Natal/KwaZulu, South Africa, 1987-1988. 1. Epidemiology.

An epidemic of type 1 poliomyelitis occurred in Natal/KwaZulu in the eastern part of South Africa between December 1987 and November 1988. 412 poliomyelitis cases were reported, of whom 74% were younger than 5 years. The case-fatality rate was 8%. It is suggested that massive floods, experienced in the area 2 months earlier, triggered the outbreak.

Adolescent↗
PubMedDate not supplied

Poliomyelitis outbreak in Natal/KwaZulu, South Africa, 1987-1988. 2. Immunity aspects.

An extensive poliomyelitis outbreak due to type 1 poliovirus took place in Natal/KwaZulu, South Africa, in 1987-1988, causing 412 paralytic cases. This epidemic differed from a previously described outbreak in Gazankulu, South Africa, in 1982 in that it occurred against a background of relatively good immunity. Thus, only 12% of patients lacked antibodies to types 2 and 3, indicating lack of previous immunization, and 76% of healthy children sampled in the epidemic area had serological immunity to all 3 types of poliovirus. The occurrence of extensive outbreaks in relatively well-immunized communities emphasizes the need to maximize herd immunity and reduce reservoirs of infection in the gut and in the environment, which can be achieved only with oral polio vaccine.

Antibodies, Viral↗
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The current epidemiology of hepatitis A infection in South Africa: implications for vaccination.

Testing stored sera from various categories of individuals has shown that among the Black population hepatitis A virus (HAV) infection is universal and most adult Black subjects are immune. Infection probably occurs early in life, consistent with the epidemiological pattern seen in the developing world. By contrast, seroprevalence of HAV infection in adult White subjects increases with age, reflecting an epidemiological pattern seen in the developed world. White subjects working in a virological laboratory and White medical students had comparatively low seroprevalences of HAV infection and could therefore represent groups at risk. Hepatitis A vaccine is likely to be available in South Africa in the near future and could be offered to these groups. Pre-vaccination immunity screening would be a cost-effective strategy.

Adolescent↗
PubMedDate not supplied

Evaluation of right subphrenic fluid collections with emission computed tomography: an experimental study.

An animal model to study subphrenic fluid collections is presented. Performance of single photon emission computed tomography (SPECT) for detection of subphrenic fluid collections was compared to that of liver-lung scintigraphy and transmission computed tomography (TCT). TCT detected a water volume of 25 ml in the right subphrenic space. This volume was barely seen using SPECT and not detectable on scintigraphy. Differences in performance of the three imaging modalities are discussed.

Animals↗
PubMedDate not supplied

An immunocytochemical analysis of torn rotator cuff tendon taken at the time of repair.

During rotator cuff repairs, it is recommended that the hypovascular tissue edge be resected. To investigate rotator cuff tendon histopathology, we performed immunohistochemistry on 8 surgical and 6 cadaveric specimens. Hoechst nuclear stain and standard hematoxylin-eosin were used for morphologic analysis. Antibody to human von Willebrand factor tagged with fluorescein isothiocyanate, conjugated, was used to visualize vascularity, and antibody to human procollagen type I tagged with Cy3 was used to visualize new procollagen synthesis. There were no significant differences in the vascularity of surgical specimens sectioned near the tear site (<2.5 mm from tear margin) and matched cadaveric controls. However, sections taken 2.5 to 5 mm away from the tear demonstrated more vessels than those taken from either control or surgical specimens within 2.5 mm of the tear (P <.001). There were no differences in nuclear distribution patterns or in procollagen production and distribution between surgical specimens from sites near the tear or away from the tear. On the basis of morphologic architecture, these data suggest that minimal debridement of tendon edges only is required to maximize healing of the rotator cuff tendon at the time of repair.

Aged↗
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Low-molecular-weight peptides derived from extracellular matrix as chemoattractants for primary endothelial cells.

The development of synthetic and naturally occurring scaffolds for tissue engineering applications has included strategies to promote attachment of specific cell types, control the rate of scaffold degradation, encourage angiogenesis, or otherwise modulate the host response. We have reported that bioscaffolds developed from porcine small intestinal submucosa (SIS) facilitate the constructive remodeling of tissues and recruit marrow-derived cells that persist long after the acute inflammatory stages have resolved. We have not yet determined which cells are recruited, the eventual fate of these cells, or via what mechanisms the events occur. We now have analyzed various molecular weight fractions of acid-hydrolyzed SIS by both functional and morphologic methods and have determined that fraction 4 (5 to 16 kDa) possesses chemoattractant activity for primary murine adult liver, heart, and kidney endothelial cells in vitro. Addition of fraction 4 to Matrigel plugs promoted in vivo vascularization when the plugs were implanted subcutaneously in mice. These results indicate that small-molecular-weight peptides derived from the degradation of porcine SIS are biologically active in the recruitment of murine endothelial cells in vitro and in vivo.

Angiogenesis Inducing Agents↗
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Postmenopausal hormone use following a 3-year randomized clinical trial.

Postmenopausal women often discontinue estrogen therapy within the first year. No studies have examined reasons why women continue or discontinue hormone replacement therapy (HRT) after several years of use, when hormone side effects have subsided. We wanted to identify determinants of estrogen use after participation in a 3-year randomized placebo-controlled trial. The Postmenopausal Estrogen/Progestin Intervention (PEPI) study compared the effects of estrogen alone or in combination with one of three progestogens with placebo. Post-PEPI use of hormone therapy was ascertained 1-4 years after the trial in 775 (90%) of the originally enrolled women. Potential correlates of treatment decisions were identified from sociodemographic characteristics, medical histories, and clinical measures ascertained at baseline and during and after the trial. Among women who had been assigned to placebo during PEPI, post-PEPI hormone use was significantly less common in women who were adherent to placebo during PEPI, older, or of non-Caucasian ethnicity. Hormone use was positively associated with hysterectomy. Among women assigned to an active regimen during PEPI, post-PEPI hormone use was significantly more common in women who used hormones before PEPI and in women who were adherent to hormones during PEPI. Older age, less education, and being non-Caucasian predicted less hormone use. Post-PEPI hormone use was highest in San Diego and lowest in Iowa City. Women on placebo who lost more bone mineral density (BMD) were more likely to begin hormones than women with less bone loss. Lipids, blood pressure, and other cardiovascular risk factors had relatively little influence on hormone use. The main predictors of post-PEPI hormone use were those associated with use in the general population (education, ethnicity, geographical region, hysterectomy, and prior use/adherence).

Age Factors↗
PubMedDate not supplied

Merging PICU and MICU: expanding nurse competencies.

Unit mergers offer an opportunity for nurses to acquire additional skills. A model for unit mergers is presented. The authors describe how didactic and clinical competencies serve as a foundation upon which the nurse develops proficiency and expertise in a new subspecialty.

Adult↗
PubMedDate not supplied

Fecal incontinence in hospitalized patients who are acutely ill.

BACKGROUND: Information about fecal incontinence experienced by patients in acute-care settings is lacking. The relationship of fecal incontinence to several well-known nosocomial or iatrogenic causes of diarrhea has not been determined. OBJECTIVES: To determine the cumulative incidence of fecal incontinence in hospitalized patients who are acutely ill, and to ascertain the relationship between fecal incontinence and stool consistency, and between diarrhea and two well-known nosocomial or iatrogenic etiologies of diarrhea: Clostridium difficile and tube feeding. The relationship of fecal incontinence and risk factors for diarrhea associated with C. difficile and tube feeding in hospitalized patients was examined. METHODS: Fecal incontinence, stool frequency and consistency, administration of tube feeding and medications, severity of illness, and nutritional data were prospectively recorded in 152 patients on acute or critical care units of a university-affiliated Veterans' Affairs Medical Center. Rectal swabs and stool specimens from patients were obtained weekly for C. difficile culture. C. difficile culture and cytotoxin assay were performed on diarrheal stools. HindIII restriction endonuclease analysis (REA) was used for typing of C. difficile isolates. RESULTS: In this study, 33% (50/152) of the patients had fecal incontinence. The proportion of total surveillance days with fecal incontinence in these patients was 0.50 +/- 0.06. A greater percentage of patients with diarrhea had fecal incontinence than patients without diarrhea (23/53 [43%] vs. 27/99 [27%]; p = 0.04). Incontinence was more frequent in patients with loose/liquid stool consistency than in patients with hard/soft stool consistency (48/50 [96%] vs. 71/100 [71%]; p < 0.001). The proportion of surveillance days with fecal incontinence was related to the proportion of surveillance days with diarrhea (r = 0.69; p < 0.001) and the proportion of surveillance days with loose/liquid stools (r = 0.64; p < 0.001). Multivariate risk factors for fecal incontinence were unformed/loose or liquid consistency of stool (RR = 11.1; 95% confidence interval [CI] = 2.2, 56.7), severity of illness (RR = 5.7; CI = 2.6, 12.3), and age (RR = 1.1; CI = 1, 1.1). CONCLUSIONS: Fecal incontinence is common in hospitalized patients who are acutely ill, but the condition was not associated with any specific cause of diarrhea. Because loose or liquid stool consistency is a risk factor for fecal incontinence, use of treatments that result in a more formed stool may be beneficial in managing fecal incontinence. However, treatments that slow intestinal transit should be avoided in patients with C. difficile-associated diarrhea.

Acute Disease↗
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A comparison of teaching strategies for integrating information technology into clinical nursing education.

As health care becomes more information-intensive and diverse, there is a need to integrate information technology (IT) into clinical education. Little is known, however, about how to design instructional strategies for integrating information technology into clinical nursing education. This article outlines the instructional strategies used by faculty in five nursing programs who taught students to use a point-of-care information technology system. The article also reports students' computer acceptance and summarizes IT clinical teaching recommendations.

Adult↗
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Respiratory nursing diagnoses: practicing nurses' selection of defining characteristics.

One-hundred medical/surgical nurses from two hospitals participated in a study designed to determine which defining characteristics professional nurses working in acute-care settings associated with each of the three respiratory nursing diagnoses identified by the North American Nursing Diagnosis Association (NANDA). All NANDA defining characteristics for impaired gas exchange and ineffective airway clearance were selected by at least 63% and 67% of the study participants, respectively. Thirteen of the 15 NANDA defining characteristics for ineffective breathing pattern were selected by at least 68% of the study participants. Two characteristics of ineffective breathing pattern identified by NANDA, cough and fremitus, were selected by only 47% and 45% of respondents. This study was the first in a series of studies intended to validate the respiratory nursing diagnoses.

Adult↗