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Biomedical subjects

J Johnston

Publications and source records attributed to J Johnston.

At least 145 records · Page 8Linked to original sources
PubMed1991

Postoperative myocardial damage in patients with coronary artery disease undergoing major non cardiac surgery.

A prospective study was carried out in a group of 50 patients with coronary artery disease, presenting for major non-cardiac surgery, to investigate the timing and incidence of further perioperative myocardial damage. A standardised anaesthetic was used. A standard 12-lead ECG was taken immediately before surgery and at 24, 48, and 72 hr after the start of anaesthesia. Blood samples were taken immediately preoperatively and at 6, 24, 48, and 72 hr after anaesthesia for total CK and CK-MB assay. Thirty-three patients (66%) showed ECG evidence suggestive of further infarction, and of these, two (4%) died in the immediate perioperative period. The first ECG change occurred in 27/31 (87%) by 24 hr, in 3/31 (10%) by 48 hr, and 1/31 (3%) by 72 hr. Twenty-nine patients (58%) including the two deaths showed CK-MB enzyme changes. The first elevation in CK-MB was nil at 6 hr and 72 hr, with 23/27 (85%) at 24 hr, and 4/27 (15%) at 48 hr. In 22/50 (44%) ECG and enzymes were correlative. Goldman and Cooperman risk indices were calculated for each patient. The Cooperman risk index was superior to the Goldman scale in the correlation of observed with predicted myocardial morbidity. Patients with ECG changes only before surgery were just as liable to further myocardial damage as those patients with ECG changes and a documented history of a previous infarct and/or symptoms. Myocardial damage is maximal in the first 24 hr after surgery, and may not be adequately predicted by current risk indices.

Adult↗
PubMed1991

Early postoperative myocardial morbidity in patients with coronary artery disease undergoing major non-cardiac surgery: correlation with perioperative ischaemia.

As a part of a study assessing early postoperative myocardial morbidity in 50 patients with active coronary artery disease undergoing major non-cardiac surgery, the ECG was monitored continuously for 24 hr after the onset of anaesthesia, using a frequency modulated (FM) Holter monitor. Concurrent automated blood pressure and pulse were measured non-invasively at three-minute intervals during anaesthesia and subsequently at five-minute intervals. Thirty patients were monitored with two-site ECG recordings, from modified V1 and V5 (Group A). Twenty patients had seventeen-site ECG monitoring, multiplexing a four by four array of precordial electrodes onto one channel of the frequency modulated recorder (Group B). Tapes were analyzed for noise, supraventricular and ventricular dysrythmias, runs of tachy- and bradycardia, and ST segment changes. These data were correlated with serial standard 12-lead ECGs and CK-MB assay in the 72 hr after surgery. Seven tapes from Group A could not be analyzed. Change (greater than 1 mm) on ST monitoring from both Groups A (14/23), B (14/20), correlated with serial 12-lead ECG and/or CK-MB changes. The majority of first ST change 19/28 (70%) occurred after anaesthesia. In 14/28 (50%) ST change occurred during episodes of tachycardia and elevated blood pressure (greater than 20% above baseline). Nine patients (9/23) in Group A had no ST change; however, six had serial 12-lead ECG and/or CK-MB changes. Six patients (6/20) in Group B had no ST changes, and none of these patients had any change of serial 12-lead ECGs or CK-MB assay. No patient complained of chest pain during the Holter monitoring period. Continual monitoring of heart rate and blood pressure and accurate ST monitoring are essential to detect and treat perioperative myocardial ischemia. A multiple-lead precordial system is substantially more sensitive than traditional two-lead ECG holter monitoring in detecting myocardial ischaemia.

Arrhythmias, Cardiac↗
PubMed1991

Conversational skills of individuals with fragile-X syndrome: a comparison with autism and Down syndrome.

The conversational skills of 18 individuals with fragile-X syndrome (FXS) were compared with those of two other matched groups with autism and Down syndrome. The FXS group used more eliciting forms in conversation than those with Down syndrome, and also used partial self-repetition more often than the other two groups. The Down syndrome group had more speech dysfluencies than those with autism, but not more than those with FXS. The autistic group used more inappropriate phrases. Qualitative analysis of behavioral phenotype may reveal differences in communicative organization among subgroups whose retardation is based on different genotypes. In addition, analysis of verbal strategies during conversation suggests important differences between individuals with FXS and autism.

Adolescent↗
PubMed1991

A method to prevent wrinkles in autoradiographic emulsion when staining plastic embedded sections with hematoxylin and eosin-phloxine.

A procedure was developed which prevents wrinkles in autoradiographic emulsion when sections, embedded in glycol methacrylate, are stained with hematoxylin and eosin-phloxine. Craniofacial tissues labeled with tritiated thymidine were collected and mounted on slides. Slides were dipped in emulsion, stored for one month and developed. The slides were immersed in liquefied celloidin and subsequently stained with a modified hematoxylin and eosin-phloxine procedure. Results showed that the emulsion did not wrinkle and the procedure did not effect the occurrence of labeled cells.

Animals↗
PubMed1991

A new beginning: current trends in pediatric heart transplantation.

Recent experience with heart transplantation in the newborn infant as a surgical option for the treatment of HLHS and other fatal heart abnormalities has encouraged the outgrowth of infant heart transplant programs throughout the world. Current trends include noninvasive evaluation of rejection, minimizing immunosuppressive therapy in this age group, and evaluating societal issues such as the cost of transplantation and parental compliance as an indicator of outcome. Implications for nursing practice involve the support of infants and their families during the evaluation process, thus allowing families to receive appropriate counseling regarding their options. This support may include the obstetric nurse in a small hospital or the nurse practitioner in the neonatal intensive care unit. Heart transplant coordinators facilitate the rapid transfer of information from the transplant center to the referring facility regarding management principles that are necessary to support an infant dying of HLHS. Nursing implications in the psychosocial arena include assessing family compliance in an effort to determine its impact on a successful surgical outcome. After transplantation, nursing practice is challenged by participating in the determination of rejection, and contributing to long-term follow-up care.

California↗
PubMed1991

Gay.

Explore the source record for details and available documents.

Homosexuality↗
PubMed1991

Role of the pediatric nurse in selection and support of potential donors for heart transplantation.

Success in transplantation requires a team effort by many individuals who are committed to the process of prolonging life. Today, health care professionals must always consider both brain-dead and gravely injured patients as potential organ donors. With more than 15,000 persons waiting for organs at any time, hundreds die because others do not even attempt to make potential organs available. But even more important, families of potential donors are not given the chance to find some good to come out of their tragedy.

Brain Death↗
PubMed1990

Molecular phenotype of a pediatric small round cell tumor.

Molecular probes were used to characterize an unusual small round cell abdominal tumor arising from the fallopian tube of a 15-year-old girl. DNA and RNA extracted from the tumor and adjacent normal tissue was subjected to Southern and Northern blot analysis using a variety of different probes. N-myc oncogene RNA was greatly expressed in the tumor, but was not expressed in normal tissue or amplified in chromosomal DNA. Insulin-like growth factor II RNA was similarly overexpressed in the neoplasm, but not in normal tissue. While histopathologic studies could not distinguish between a neuroectodermal neoplasm and Wilms' tumor, electron microscopy and the pattern of gene expression was most consistent with Wilms' tumor.

Adolescent↗
PubMed1990

Kidney transplantation under FK 506.

The experimental immunosuppressive drug FK 506 was given to 36 renal transplant recipients, many of whom were highly sensitized. Ten were undergoing kidney retransplantation, 10 also underwent liver transplantation at an earlier time (6 patients) or concomitantly (4 patients), and 2 patients received a third organ (heart or pancreas) in addition to a liver and kidney. With follow-ups of 4 to 13 months, all but 2 of the 36 patients are alive, 29 (81%) are dialysis free, and most have good renal function. Twenty of the 29 dialysis-free patients are receiving no or low-dose (2.5 to 5.0 mg/d) prednisone therapy. Only one kidney was lost to cellular rejection. However, patients who had antidonor cytotoxic antibodies in current or historical serum samples had a high rate (3 of 9) of irreversible humoral rejection. A low incidence of posttransplant hypertension was noteworthy. Hirsutism and gingival hyperplasia were not observed. Serum cholesterol levels in patients who took FK 506 were unexpectedly low, and the effect on the level of uric acid was minimal. The side effects of FK 506 therapy include nephrotoxicity, neurotoxicity, and potential induction of a diabetic state. These are similar to the side effects of cyclosporine use, but probably less severe. The seeming safety, efficacy, and relative freedom from side effects of FK 506 encourage further trials in kidney transplantation.

Adult↗
PubMed1990

The intergroup Hodgkin's disease in children. A study of stages I and II.

A total of 228 previously untreated and eligible children with pathologic Stage I or II Hodgkin's disease were registered in the Intergroup Study of Hodgkin's Disease in Children between February 1977 and April 1981. Patients were randomized in the Southwest Oncology Group (later the Pediatric Oncology Group [POG] to involved-field (IF) radiotherapy alone or IF radiotherapy followed by six courses of mechlorethamine, vincristine, prednisone, and procarbazine (MOPP) chemotherapy; patients in the Children's Cancer Study Group (CCSG) and Cancer and Leukemia Group B (CALGB) were randomized to receive extended-field (EF) radiotherapy or IF radiotherapy followed by six courses of MOPP. An estimated 97% of patients receiving IF + MOPP were relapse-free and surviving (RFS) at 5 years, which was significantly better than 41% for patients receiving IF alone; however there was essentially no overall difference in survival experience between groups. Patients in CCSG and CALGB receiving IF + MOPP had significantly superior RFS at 5 years than patients receiving EF. Survival rate was not different between these two groups, an estimated 93% of patients surviving 5 years or longer. Although patients were not randomized between IF or EF radiotherapy, they were similar with respect to patient characteristics. There was some statistical evidence that RFS was superior at 5 years for patients receiving EF than for IF; however, there was no evidence of a difference in survival experience. The percentages of patients with late effects of therapy were not significantly different by treatment. The most common types of late effects were endocrine dysfunction and impaired resistance to infection. Overall, the response rate to therapy for relapse patients was good, being 83% among all patients who relapsed. Patient characteristics related to poor prognosis were the presence of constitutional (B) symptoms (fever, night sweats, and weight loss) and poor performance status.

Adolescent↗
PubMed1990

Evaluation of adverse events after influenza vaccination in hospital personnel.

Reactogenicity of trivalent influenza vaccine prepared for the 1988-89 season was assessed as part of a first-time voluntary influenza prevention program among hospital staff. Of approximately 500 full-time workers in areas with the highest concentrations of patients at high risk for influenza complications offered the vaccine 288 accepted. Of these, 266 (92%) returned a questionnaire regarding any symptoms experienced within 48 hours after vaccination; 238 (90%) of the respondents reported adverse effects. Soreness at the injection site was described by 229 subjects, 58 (25%) of whom had constant aching and 123 (54%) soreness with arm movement. Symptoms resolved in 1 to 2 days, and only 21 (9%) of those who reported symptoms said they took analgesic medication. Systemic adverse effects were described by 130 subjects (49%). Intercurrent illness accounted for some of these complaints, but 65 people (24%) described at least two of the following symptoms: generalized aching, tiredness, nausea, chills or onset of fever within 12 hours after vaccination (a symptom complex previously attributed to influenza vaccine). Systemic symptoms resolved within 0.5 to 2 days. Thirteen subjects (5%) reported missing work because of arm soreness (1 subject) or systemic symptoms (12). Adverse effects were encountered more often than expected, probably because most of the workers were young and lacked immunity to influenza. Acceptability of the program could likely be improved by using a split-virus vaccine.

Absenteeism↗
PubMed1990

Embryo-derived platelet activating factor, a marker of embryo quality and viability following ovarian stimulation for in vitro fertilization.

Embryo-derived platelet-activating factor (PAF) may be an important mediator of early maternal recognition of pregnancy. PAF was higher in media associated with clinical pregnancies when compared to preclinical pregnancies but not higher in pregnant vs nonpregnant groups. The production of PAF by the preimplantation embryo was not related to follicle size or embryo morphology. However, differences in PAF concentrations in the culture media were related to the age of the embryo culture medium and the developmental stage of the embryo.

Biomarkers↗
PubMed1990

Secondary surgical procedures to evaluate primary tumor status in patients with chemotherapy-responsive stage III and IV sarcomas: a report from the Intergroup Rhabdomyosarcoma Study.

Fifty children with clinical group III (localized, but unresected) or clinical group IV (disseminated) soft tissue sarcomas were entered in a trial to determine if the addition of etoposide and cisplatin to standard chemotherapy regimens and irradiation (4,000 cGy) would be tolerated by pediatric patients. Responding patients had a secondary surgical procedure performed after approximately 20 weeks of therapy for the purpose of establishing histological response, determining its extent, and removing residual tumor tissue, when feasible. Such procedures were performed in 29 of 50 (58%) of these patients, ie, 20 of 31 (65%) of those in group III, and nine of 19 (47%) of those in group IV. Surgical procedures consisted of exploration of the site and biopsy (only) in 16 patients; grossly complete tumor excision in nine; and subtotal tumor excision in four. In nine patients (six in group III, three in group IV) apparent total excision of a previously unresected primary tumor mass was accomplished at second surgery. One distant but no local relapse has occurred in this group, and eight of nine have survived (five of six with identified tumor in the specimen) for a duration of 232 to 348 weeks (six greater than 260 wks), suggesting that among patients with primary tumors in selected sites, with either stage III or stage IV disease, excision of residual masses following intensive chemotherapy/radiotherapy regimens may favorably influence outcome. Local relapse subsequently occurred in seven of 18 patients in whom tumor tissue could not be identified in biopsy specimens or in excised masses taken from the primary site at second surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Partial cystectomy in the management of rhabdomyosarcoma of the bladder: a report from the Intergroup Rhabdomyosarcoma Study.

Among 154 children with primary vesical rhabdomyosarcoma entered in the IRS (1972 to 1986), tumor excision constituting a partial cystectomy was performed in 33. These procedures were performed in the following situations (1) as an initial operation for localized disease (22); (2) as a secondary procedure for localized disease following chemotherapy (CT) or CT/irradiation response (6); and (3) as an initial operation in the presence of disseminated abdominal disease (5). Partial cystectomy included full-thickness resection of 15% to 80% of the bladder wall. Ureters were reimplanted or revised in two patients. The 33 patients undergoing partial cystectomy were in the following clinical groups: I, total excision (10); II, gross excision with "microscopic residual" or positive nodes (8); III, subtotal excision (10); and IV, tumor dissemination (5). Patients in clinical groups I and II received vincristine and actinomycin-D (VA) or VA + cyclophosphamide (VAC) +/- adriamycin (ADR). Patients in groups III and IV received the same agents +/- cisplatin. Irradiation (2,000 to 5,000 cGy) was administered to 18 patients (55%) in groups II to IV. Six relapses occurred among 28 patients with localized disease, and one among five patients with dissemination; all resulting in progressive disease and/or death. Estimated 3-year survival following partial cystectomy (79%) is similar to that for all patients with primary bladder tumors (78%). In contrast with the total group, in which the majority of survivors have eventually required total cystectomy; 25 of 26 survivors of partial cystectomy have functional bladders from 146 to 686 weeks (median, 356 weeks) from study entry.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Miniature language system acquisition by children with different learning proficiencies.

Sixteen children, aged 7:8 to 9:10, learned two miniature languages while playing a communication game. Both languages expressed Action (Agent, Patient) meanings and incorporated a Patient suffix. They differed in word order: VSO (Language I) versus SOV (Language II). Children found the SOV language easier; they also made more suffix errors and fewer word order errors in this language. The results suggest that the perceptual salience of an utterance-final particle may hinder grammatical analysis, at least if capacity limits and perseverative learning strategies intervene.

Attention↗
PubMed1990

Characterization of an rRNA gene-specific cDNA probe: applications in bacterial identification.

Discontinuous DNA complementary to Escherichia coli 16S + 23S ribosomal RNA was synthesized by random oligonucleotide priming using reverse transcriptase. cDNA generated from native or denatured rRNA template was labelled by incorporation of either [alpha-32P]dCTP or digoxigenin-labelled dUTP during synthesis, followed by template hydrolysis. The specific activity of the radiolabelled cDNA was 10(7)-10(8) c.p.m. (micrograms rRNA template)-1 with 60-92% incorporation after 5 h. The length of the reverse transcript was between 20 and 1140 nucleotides and was unaffected by exclusion of primer. The cDNA probe could detect 3 pg rRNA by quantitative slot blot. In the non-radiolabelling digoxigenin system 3 micrograms template gave 0.5-2.0 micrograms cDNA after 24 h with a length of between 100 and 1225 bases. This probe could detect 50 pg rRNA. Probes were evaluated in the comparison of Pasteurella haemolytica biotypes by hybridization to Southern blots of restriction-endonuclease-digested total DNA. The digoxigenin-labelled probe was used to identify clinical isolates of Campylobacter jejuni to demonstrate its potential use in laboratories requiring high-sensitivity detection without the use of radioisotopes.

Alkaline Phosphatase↗