Search PubMed⌕ Search

Biomedical subjects

W R Johnson

Publications and source records attributed to W R Johnson.

At least 19 recordsLinked to original sources
PubMed1992

Subjective underemployment and psychosocial stress: the role of perceived social and supervisor support.

The purpose of this study was to examine the effects of subjective underemployment on psychosocial stress. The moderator effects of perceived social and supervisor support were also investigated. Data were collected during the summer of 1987 in a public utility governmental agency in the United States. The sample size was 212 with a 71% response rate. Multiple regression analysis was used to examine the relationship between subjective underemployment and psychosocial stress. As expected, the results revealed a significant positive relationship between subjective underemployment and five indexes of psychosocial stress. The interactions between subjective underemployment and social and supervisor support were not significant; however, the relationships were in the expected directions. Supervisor support was positive and significantly related to psychosocial stress, but social support was not.

Adaptation, Psychological↗
PubMed1991

Application of microcolumn liquid chromatography-continuous-flow fast atom bombardment mass spectrometry in environmental studies of sulfonylurea herbicides.

The use of 0.25-mm I.D. packed capillary liquid chromatography columns coupled with continuous-flow fast atom bombardment (FAB) mass spectrometry has proven to be a very valuable technique, especially for the identification of unknown sulfonylurea herbicide metabolites. Several new and unusual heterocycle ring-opened metabolites and hydrolysis products were identified, and metabolic pathways were proposed. Typical column flow-rates are 1-2 microliters/min, which allows direct coupling with no sample splitting. This is important in our metabolite identification work, since we are usually sample-limited. Techniques for increasing injection volume to allow analyses of dilute solutions and the use of polymeric packing for separation of polar metabolites are discussed. The FAB mass spectra usually provide unequivocal molecular weights and structurally useful fragments ions, which often allows structure assignments on exceedingly small quantities of isolated metabolites.

Animals↗
PubMed1991

Tension pneumoperitoneum after cardiopulmonary resuscitation.

OBJECTIVE: To increase awareness of the unusual complication of pneumoperitoneum after cardiopulmonary resuscitation. CLINICAL FEATURES: A 57-year-old male farmer with a history of chronic renal failure and heart disease, as well as severe oesophageal reflux for which fundoplication had been performed, developed a tension pneumoperitoneum after cardiopulmonary resuscitation. This resulted in lower limb cyanosis and an erection, a previously unreported complication. INTERVENTION AND OUTCOME: The tension was relieved by uncapping a peritoneal dialysis catheter that was in situ. The cyanosis and erection resolved immediately, suggesting that the tension pneumoperitoneum had caused significant venous obstruction. A 3 cm defect in the posterior wall of the stomach was repaired. CONCLUSION: The likelihood of pneumoperitoneum is reduced if standard guidelines for cardiopulmonary resuscitation are adhered to.

Abdomen↗
PubMed1991

Percutaneous laparoscopic cholecystectomy: the first fifty.

A series of 50 percutaneous laparoscopic cholecystectomies was performed by one surgeon between 7 June and 25 October 1990 using a modified technique as described by Dubois. There were 42 females and 8 males, the average age being 44 years with a range of 14-76 years. The average operating time was 80 min, ranging from 35 to 210 min. Postoperative stay averaged 2.9 days and there was an average of 11 days to return to work. Complications consisted of a subhepatic bile collection requiring open drainage, one minor wound infection and one minor abdominal wall haematoma. Laparoscopic cholecystectomy is a safe technique for removing the gall-bladder resulting in a rapid convalescence and early return to work. The initial learning curve is long and careful case selection should be carried out in this phase.

Adolescent↗
PubMed1990

Two children with lethargy and intussusception.

The cases of two patients with lethargy as the predominant symptom of intussusception are described. The first patient was admitted to the pediatric ICU with unexplained lethargy. The diagnosis of intussusception was made after he developed right lower quadrant abdominal tenderness and heme-positive stool. The second patient was diagnosed after presenting to the emergency department with intermittent lethargy, right lower quadrant abdominal tenderness, and heme-positive stool. The presence of gastrointestinal symptoms or signs in association with lethargy should alert the physician to the possibility of an intussusception.

Abdominal Pain↗
PubMed1987

Lung recurrence after curative surgery for colorectal cancer.

A total of 1578 patients were treated with potentially curative surgical resection for colon and rectal cancer by one surgeon from 1950 to 1982. Follow-up revealed that 117 (11.5 percent) of 1013 patients with rectal carcinoma eventually presented with clinical evidence of pulmonary recurrence, with or without evidence of spread elsewhere; the corresponding figures for the colon were 20 (3.5 percent) of 565 (P less than 0.001). An analysis of the times to recurrence revealed that half of the lung recurrences were clinically obvious within 32 months for rectal tumors and 34 months for colonic, compared to 22 and 21 months, respectively, for liver recurrences, excluding those with other distant metastases. The slower recurrence rate and the longer survival in patients with recurrences in the lung compared to the liver were statistically significant only for rectal primaries (P less than 0.02 and P = 0.001, respectively). Sixteen patients underwent surgery with curative intention for lung recurrences; four of these remain alive at two, six, 11, and 15 years, and one patient was free of recurrence when he died from other causes 15 months after surgery. The conditional probability survival rate for the 16 patients was 38 +/- 13 percent at five years after recurrence operation.

Colonic Neoplasms↗
PubMed1987

Oesophagectomy without thoracotomy in the treatment of oesophageal carcinoma.

A group of patients with carcinoma of the oesophagus and cardia has been studied. Subtotal oesophagectomy without thoracotomy has been performed. The operation is briefly described, the complications and results are discussed and it is concluded that the operation of subtotal oesophagectomy without thoracotomy does have a place in the treatment of selected patients with carcinoma of the oesophagus.

Adenocarcinoma↗
PubMed1987

Aggressive angiomyxoma of the female pelvis.

A 42 year old female presented with a 6 year history of a perineal mass. Clinically it had all the features of a perineal hernia. Two previous attempts to repair the 'hernia' had been performed. At operation an aggressive angiomyxoma of the female pelvis was identified and resected via an abdomino-perineal combined approach. The case is discussed with reference to the literature.

Adult↗
PubMed1986

Changing survival prospects in rectal carcinoma. A series of 1,306 patients managed by one surgeon.

Cancer-specific survival prospects for rectal carcinoma in a series of 1306 patients managed from 1950 to 1979 by one surgeon worsened from 1970 to 1979. The prognosis was worse for all patients treated operatively from 1970 to 1979 compared with 1960 to 1969 (P less than 0.03). After potentially curative resection, survival was worse from 1970 to 1979 compared with 1950 to 1959 (P less than 0.02) and 1960 to 1969 (P less than 0.01), respectively; the corresponding five-year survivals were 72.5 percent, 72.3 percent, and 61.5 percent. The curative resection rate for the three decades was similar (66 to 70 percent). An increase in the incidence of Dukes' Stage C tumors from 23.3 percent to 32.3 percent (P less than 0.01) explains, at least partly, the decreased survival. The worsened survival prospects were not accounted for by changes in referral pattern, tumor site, or in the proportion of sphincter-saving resections performed. The worsening was paradoxically paralleled by earlier symptomatic presentation (P less than 0.001). Analyses of other Australian data are required to test the hypothesis that the worsened survival prospects are consequent to altered tumor biologic aggressiveness, possibly related to differences in the causal factors operating over the 30-year study period.

Adult↗
PubMed1986

Examination of the secondary structure of the kringle 4 domain of human plasminogen.

The structure of a small region of human plasminogen (F4), consisting of amino acid residues Val354-Ala439 and containing its kringle 4 (K4) domain (residues Cys357-Cys434), has been predicted from Chou-Fasman calculations and hydropathy profiles, and compared to circular dichroism (CD) measurements on the isolated fragment. Calculations, by the Chou-Fasman method, of the probabilities of various types of secondary structures that exist in this region reveal that no helical structures are present. Of the total of 86 amino acid residues present in this K4-containing peptide region, 37% can adopt conformations of beta-pleated sheets, 48% of the amino acids can exist in beta-turns, and 15% of the residues can be present as coils. The structure of F4 in dilute aqueous solution has been experimentally evaluated by CD measurements. At pH = 7.4, in dilute salt solutions, a total of 64% beta-structures, 30% beta-turns, and 6% coiled structures is estimated to be present in this peptide region. Consideration of the marginal stability of many of the conformational regions of F4, as predicted by Chou-Fasman calculations, suggests that secondary structural flexibility is present in this fragment, which could result in ready adoption of new conformations. The hydropathy profile of F4 has been determined and suggests that this polypeptide is highly hydrophilic, especially in the regions of residues His387-Tyr396 and Cys406-Lys413. Thus, it appears as though a large portion of the surface of F4 can be exposed to solvent in its native conformation.

Chymotrypsin↗
PubMed1986

Gastric rupture following cardiopulmonary resuscitation.

Three cases are reported in which gastric rupture occurred during cardiopulmonary resuscitation. Precipitating factors are considered and discussed with reference to the literature. This condition has been considered to be rare. Its occurrence greatly adds to the morbidity and mortality of the underlying disease. Possible precautions to limit its occurrence are discussed.

Aged↗
PubMed1986

Activation of complement at plasma-air or serum-air interface of rabbits.

The possibility of the air-plasma interface giving rise to complement activation is investigated. After incubation of the plasma of a group of rabbits with zymosan and measurement of the degree of autologous polymorphonuclear leukocyte aggregation that follows the injection of a sample of the incubated plasma into a leukocyte suspension, it is found that the rabbits can be divided into two groups, sensitive and insensitive, depending on the degree of leukocytes aggregation. For the sensitive group it is found that both the plasma-air interface and the serum-air interface give rise to significant leukocyte aggregation. If the animal is decomplemented before the plasma is incubated in the presence of the air interface, there is no longer any significant leukocyte aggregation. It would appear that the complement system is activated by the presence of the air interface in plasma, but that fibrinogen does not play a pivotal role in the process.

Air↗
PubMed1986

The outcome of patients with ulcerative colitis managed by subtotal colectomy.

A total of 1,494 patients with a diagnosis of ulcerative colitis were managed by one surgeon between 1950 and 1981. Subtotal colectomy was performed upon 286 patients of whom 82 had a primary and 65 a secondary ileorectal anastomosis. There was no significant difference in the postoperative mortalities between patients treated by subtotal colectomy (8.7 per cent) and a group of 71 patients treated by proctocolectomy (9.9 per cent). The postoperative mortality after primary and secondary ileorectal anastomosis was 6.9 and 1.5 per cent, respectively. Rectal excision because of disease activity was required in 109 patients after subtotal colectomy (13 after primary and nine after secondary ileorectal anastomosis) with a postoperative mortality of 0.5 per cent. The probability of rectal excision was 21 per cent at 12.6 years after primary anastomosis and 19 per cent at 16.2 years after secondary ileorectal anastomosis. Carcinoma of the rectum has developed in 11 (3.8 per cent) of the patients after subtotal colectomy. The probability of having carcinoma of the rectum develop was 17.1 per cent at 27 years after primary anastomosis and 20.0 per cent at 24 years after secondary ileorectal anastomoiss, the time beyond which no disease has yet been diagnosed in either group. The disease was advanced in stage and of high histologic grade with a median cancer specific survival time of 14 months.

Adult↗
PubMed1985

Local recurrence after potentially curative resection for rectal cancer in a series of 1008 patients.

Local recurrence and its related mortality after potentially curative resection for rectal cancer have been analysed in a series of 1008 patients managed by one of the authors. Nine hundred and thirty-four were available for analysis of recurrence. One hundred and seven (11 per cent) patients developed local recurrence without evidence of systemic spread and 84 (9 per cent) both local and systemic recurrence. Local recurrence was less common (14 per cent) after resection of tumours of the upper third of the rectum compared with the middle (21 per cent) (P = 0.02) or lower thirds (26 per cent) (P less than 0.001). Local recurrence was related to both tumour stage and differentiation (P less than 0.001). There was no significant relationship between local recurrence and tumour size or the type of curative resection performed, restorative or non-restorative. The distal margin of clearance after restorative resection did not influence the local recurrence rate. Of patients who developed metastases recurrence was evident within 2 years in 60 per cent. Three hundred and thirty-two patients died from recurrence, 91 (27 per cent) with evidence of local recurrence only, 80 (24 per cent) with combined local and systemic recurrence and 161 (48 per cent) with evidence of systemic spread only. The corresponding median survivals were 35, 34 and 39 months.

Aged↗
PubMed1985

T-antigen expression by peanut agglutinin staining relates to mucosal dysplasia in ulcerative colitis.

Staining of 326 rectal mucosal biopsies from ulcerative colitis patients with peanut agglutinin (PNA), which binds to the T-blood group antigen and has been claimed to reflect a cancer-associated mucin alteration, showed highly significant direct associations with mucosal dysplasia (P less than 0.001), disease activity (P less than 0.001), and subsequent development of rectal cancer in a smaller series of patients (P = 0.005). Staining for normal colonic mucin by the Dolichos biflorus (DBA) lectin related significantly and inversely to dysplasia. Intense normal colon mucin staining by DBA related significantly (P less than 0.025) to long disease duration and to subsequent development of cancer (P = 0.02). The latter association is based on a small number of patients only and is not considered conclusive evidence, but may provide a link with goblet-cell hyperplasia. The authors conclude that although T-antigen expression relates to dysplasia, the findings of "false" positive and negative rates of 22 and 33 percent respectively, make it unlikely that staining of biopsy sections for the T-antigen by peanut agglutinin will contribute materially to routine assessment for dysplasia and cancer risk prediction in patients with ulcerative colitis.

Adult↗
PubMed1985

Post-proctectomy perineal hernia: case report and discussion.

Perineal hernia is a rare complication of pelvic surgery. Women are more commonly affected, and development of the condition is usually gradual. Although the true incidence of this problem is unknown, few cases are severe enough to require operative repair. We report the experience of one of the authors (E.S.R.H.) in post-proctectomy perineal hernia. One case required surgical repair and is presented, with a discussion of the operative management.

Abdomen↗