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Biomedical subjects

D Evans

Publications and source records attributed to D Evans.

At least 307 records · Page 17Linked to original sources
PubMed1985

A detailed examination of the in vivo and in vitro effects of ACTH on gonadotropin secretion in the adult rat.

These studies were designed to: (1) determine the effects of continuous infusion of synthetic ACTH(1-24) on postcastration changes in serum and pituitary LH, FSH and prolactin in the male rat; (2) assess the effects of adrenalectomy on the gonadotropin and prolactin response to ACTH, and (3) test the hypothesis that ACTH may directly (not via adrenal factors) alter gonadotropin secretion at the brain and/or pituitary level. Adult male rats were either orchidectomized (ORX) or orchidectomized-adrenalectomized (ORX-ADX), and were treated continuously for 6 days with ACTH(1-24) (10 micrograms/day) or saline using an osmotic minipump. Animals were killed on day 6 following castration. ACTH treatment reduced serum LH and prolactin levels in ORX rats to mean values +/- SE of 204 +/- 25 and 37 +/- 3 ng/ml respectively, compared to 366 +/- 72 and 62 +/- 7 ng/ml in saline-treated ORX animals. Serum FSH concentrations were not altered by ACTH administration. Pituitary concentrations of LH and FSH, but not prolactin were enhanced by ACTH treatment. Adrenalectomy had no effect on serum and pituitary gonadotropin and prolactin levels, but abolished the effects of ACTH on these parameters. Central (intracerebroventricular) infusion of ACTH(1-24) (6 micrograms/day X 4 days) failed to alter the rise in serum LH in male rats following orchidectomy. Acute treatment with large doses of ACTH of perifused anterior pituitary glands from male rats and chronic treatment with ACTH of enzymatically dispersed anterior pituitary cells from female rats did not influence basal or GnRH-stimulated LH secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗
PubMed1985

Stercoral perforation of the colon. Concepts of operative management.

Stercoral perforation of the colon is a direct result of ischemic pressure necrosis by a stercoraceous mass. In over 90 per cent of cases, the perforation will involve either the sigmoid or rectosigmoid colon and is consistently centrally located within a region of mucosal ulceration of varying diameter and magnitude. A review of 33 surgically treated cases from the literature along with four cases presented here, support resection, end colostomy, and either mucous fistula or Hartmann's procedure as the operation of choice with the lowest operative mortality (23%) when compared to those patients treated by either loop colostomy or exteriorization (71%) or proximal colostomy with plication of the perforation (44%). Irrigation of the distal rectal segment as that for penetrating rectal injury is also recommended.

Aged↗
PubMed1985

On transference manifestations in male patients with female analysts.

The transference issues that are specific to the psychoanalysis of male patients by female analysts have not been widely discussed in the literature. Most of the literature on this subject has indicated, contrary to the findings reported here, that full and intense erotic transference manifestations are rarely if ever seen in this therapeutic dyad. In order to clarify the issues, we have offered some definitions that may serve as a framework for future discussions. We have utilized clinical examples from the psychoanalyses of five patients to illustrate certain aspects of the transference. We have demonstrated that male patients display a full range of erotic transference phenomena with female analysts and have focused attention on certain special features of these tranferences. For example, in some cases it was only after considerable analysis of defences against aggression that the erotic transference manifestations emerged fully. We have also shown that paternal transferences occur regularly, though they may be difficult to elucidate until the later stages of analysis. We have paid special attention to the feared loss of maleness that attends male patients' identification with their female analysts.

Adult↗
PubMed1984

Diagnostic microbiology laboratory susceptibility test results discriminate distinctive antibiotic resistance plasmids.

The sizes of the zones of inhibition around routinely tested antibiotic disks classified gentamicin-resistant isolates of Klebsiella pneumoniae from one hospital into four major antibiotype classes. From each isolate of the prevalent class (A1), two plasmids could be transferred conjugally. One carried genes for resistance to tetracycline, sulfonamides, and chloramphenicol, and for the SHV beta lactamase. The other carried genes for two aminoglycoside-inactivating enzymes, APH (3')-I and AAC (3)-III, for the TEM 1 beta lactamase, and for resistance to sulfonamides. Transconjugants of either plasmid from any A1 isolate yielded the same DNA fragments after restriction endonuclease digestion, but the two plasmids had no fragments in common. Fragments or genes from either plasmid were variously combined or lacking in plasmids from variant isolates (A2, A3, and A4). Plasmids transferable from isolates of classes B and C shared no common DNA restriction fragments with each other or with either plasmid from Class A. Fragments and genes of the plasmids from C isolates, however, were identical with those of a plasmid endemic in a nearby hospital. Routine monitoring by diagnostic microbiology laboratories of distinctive antibiotypes and of the plasmids that produce them would aid infection control and antibiotic usage policy.

Anti-Bacterial Agents↗
PubMed1984

Isolation of transforming sequences of two human lung carcinomas: structural and functional analysis of the activated c-K-ras oncogenes.

Human lung tumors PR310 and PR371 maintained in nude mice contain activated c-K-ras oncogenes detectable by the ability of their DNAs to induce the morphological transformation of NIH 3T3 mouse fibroblasts. Using phage libraries constructed with DNA from NIH 3T3 mouse fibroblast transformants, we have isolated human sequences that span greater than 40 kilobase pairs of the c-K-ras oncogene. Based on the conservation of these human sequences in mouse fibroblast transformants, we conclude that the transforming ability of the oncogene activated in these tumors resides within a 43- to 46-kilobase-pair DNA region. No clear differences were observed between the structures of the PR310 and PR371 cloned oncogene sequences. Nucleotide sequence analysis in concert with DNA transfection experiments suggests that the PR371 oncogene has been activated by a single base change in the first exon, which results in the substitution of cysteine for glycine in position 12 of the predicted amino acid sequence. The genetic alteration responsible for the transforming activity of the PR310 oncogene, however, does not reside in the first exon. These results indicate that the activation of the c-K-ras oncogene in human lung cancer can occur by different mutational events.

Amino Acid Sequence↗
PubMed1984

Changes in children's school performance as a result of education for family management of asthma.

This paper describes the impact of an asthma self-management program for parents and children on the school performance and adjustment of children with asthma. Program participants were predominantly low income, minority families enrolled in four pediatric outpatient clinics. The educational content of the program was based on a needs assessment of the participants and recommendations of medical consultants. Parents and children participated separately in group sessions that focused on the development of self-management skills and problem solving. The program was organized into six themes including "how to help your child (yourself) do well in school." The program was evaluated with an experimental research design and yielded significant school related benefits. Children participating in the program maintained better grades. Math, reading and science grades were higher relative to control group children in the year following the program. Within a subgroup of children who received care from private practitioners, program children exhibited better social adjustment to school than did control group children.

Achievement↗
PubMed1984

Application of monoclonal antibodies for the identification of the antigenic site for poliovirus neutralization.

Antigenic mutants of type 3 poliovirus were obtained by picking plaques formed in the presence of neutralizing monoclonal antibodies. All the mutants were clustered into a single operationally defined antigenic site based on their reactions with a panel of antibodies. Most of the mutations were shown to be located in the virion protein VP1 by SDS-PAGE and oligonucleotide mapping and fifteen of sixteen mutants had single point mutations in a region of VP1 encompassing only eight amino acids, suggesting that this is a major target for the neutralization of the virus. While other areas may also be required, it is likely that this region is a necessary component of a vaccine of any kind.

Antibodies, Monoclonal↗
PubMed1983

Predominant integration end products of infecting bacteriophage Mu DNA are simple insertions with no preference for integration of either Mu DNA strand.

The integration of 32P-labeled infecting Mu DNA into the Escherichia coli chromosome was investigated. Cleavage of the integrated Mu DNA with restriction endonuclease EcoRI, which cuts twice in the Mu genome, liberated the internal EcoRI fragment but not the left and right end fragments. The ends of the Mu genome became fused with host DNA at a variety of locations generating a smear of radioactive DNA fragments following cleavage with EcoRI. The predominant integration end products of infecting Mu DNA molecules are therefore generated by a mechanism which results in simple insertions and not cointegrates. Since predominantly simple insertions are found after infection (during lysogenization or lytic growth) but not after prophage induction, the transposition mode which is utilized appears to be a function of the source of the transposing DNA. Use of the integrated, 32P-labeled Mu DNA as a hybridization probe with the separated strands of Mu DNA or lambda phages carrying various regions of Mu showed no strand preference in the integration process. Both labeled DNA strands at both ends of the Mu genome were integrated. These results suggest the lack of a site-specific recombination site in the genome; the simple insertions which are the end products of Mu DNA integration following infection appear to be generated by a separate pathway rather than by the resolution of cointegrate structures.

Bacteriophage mu↗
PubMed1983

Effects of cigarette smoking on fasting triglyceride, total cholesterol, and HDL-cholesterol in women.

We examined the relationships of cigarette smoking with fasting triglycerides, total cholesterol, and high-density lipoprotein cholesterol (HDL-C) levels among a group of 191 white women aged 20 to 40 years. The mean triglyceride level among current smokers was 100.0 mg/100 ml and among nonsmokers was 68.4 mg/dl (p less than 0.005). Mean total cholesterol values among current smokers and nonsmokers were, respectively, 197.0 and 189.1 mg/dl (p less than 0.1). Mean HDL-C levels were 45.0 mg/dl among women who were smoking and 52.1 mg/dl among nonsmokers (p less than 0.005). Simultaneous adjustments for the effects of age, weight, height, blood glucose, resting pulse, and oral contraceptive use did not materially alter these relationships. A modest portion of the effect of cigarette smoking on risk of coronary heart disease may be explained by an adverse effect of cigarette smoking on blood lipids.

Adult↗
PubMed1983

Extraocular muscle surgery for dysthyroid myopathy.

A series of 45 patients underwent extraocular muscle surgery for diplopia induced by dysthyroid myopathy. Two thirds (31) of the patients were female and age distribution showed a peak (47%) in the sixth decade of life. The most common deviation was pure hypotropia; a combination of hypotropia and esotropia was also frequent. Initial surgical intervention restored binocularity in primary position in 30 patients and in reading position in 27 patients. After further surgery in some cases, 40 patients eventually achieved satisfactory alignment in primary position and 36 achieved it in reading position.

Adult↗
PubMed1983

Percutaneous transhepatic biliary drainage. Complications due to multiple duct obstructions.

The medical histories of fifty-three consecutive patients who were scheduled for percutaneous transhepatic biliary drainage (PTBD) were reviewed for incidents of sepsis. Among the 52 patients who were successfully catheterized, there were 14 incidents of sepsis, three incidents of abscess and sepsis, and two incidents of sepsis following a pulled catheter (a total incidence of 36.5%). In 14 instances, the sepsis was attributed primarily to the presence of enteric bacteria combined with bile stasis caused by multiple duct obstruction from disseminated malignancy. The presence of bacteria in the bile of well-drained patients did not necessarily lead to sepsis. This series highlights the importance of medical alert for signs of sepsis in biliary drainage patients and suggests that external drainage is preferable in patients with incomplete emptying of the biliary system during PTBD.

Abscess↗