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Biomedical subjects

D King

Publications and source records attributed to D King.

At least 289 records · Page 16Linked to original sources
PubMed1975

Chromosomal evolution in the lizard genus Varanus (reptilia).

The karyotypes have been determined of 16 of the 32 species of the genus Varanus, including animals from Africa, Israel, Malaya and Australia. A constant chromosome number of 2n = 40 was observed. The karyotype is divided into eight pairs of large chromosomes and 12 paris of microchromosomes. A series of chromosomal rearrangements have become established in both size groups of the karyotype and are restricted to centromers shifts, probably caused by pericentric inversion. Species could be placed in one of six distinct karyotype groups which are differentiated by these rearrangements and whose grouping does not always correspond with the current taxonomy. An unusual sex chromosome system of the ZZ/ZW type was present in a number of the species examined. The evolutionary significance of these chromosomal rearrangements, their origin and their mode of establishment are discussed and related to the current taxonomic groupings. The most likely phylogenetic model based on chromosome morphology, fossil evidence and the current distribution of the genus Varanus is presented.

Animals↗
PubMed1975

Spontaneous and estrogen-produced tumors in Nb rats and their behavior after transplantation.

Tumors in rats of the Nb strain, arising either spontaneously or after prolonged treatment with s.c. pellets of estrogen, were transplanted to establish whether hormone conditioning was required for their growth. Whereas all spontaneous tumors arising in males and many of those in females were autonomous on transplant, most of those arising in estrogenized rats continued to require hormones for growth after transplantation. The latter included carcinomas of the adrenal cortex, breast, pituitary ectopic tissue, ovary (thecomas), Leydig cells of testis, thymus, pancreas,salivary glands, oribital gland (fibroadenoma), liposarcoma, and lymphoma. Many of the tissues of origin of the tumors have not been considered to be under theinfluence of estrogens. A type of hormone-responsive tumor that was inhibited by estrogen and that grew only in normal rats is described. Ali estrogens tested, including estriol , were interchangeable in action. The incidence of the more common tumors of the adrenal, breast, and pituitary was very low in normal rats, but higher in females. All tumors were more common after estrogenization in both sexes, particularyly in older animals. The secretion of steroids and pitiutary hormones by many tumors led to obvious biological effects. Pituitary secretion led to severe lesions frequently associated with diseases in humans, but the signs of such diseases in the rat apparently were hormone dependent and disappeared if the tumor was removed. The overall results raised the possiblity that estrogens were not carcinogenic per se but stimulated the growth of previously altered cells and that, following their transplantation, this hormone requirement was retained. Irrespective of the mechanism of carcinogenesis, hormone-dependent tumor growth was not irreversible but was controlled in an unexpectedly wide spectrum of organs by exogenous estrogen. Host factors may play a major role in controlling the growth of many tumors and the ultimate course of the disease.

Adrenal Cortex Neoplasms↗
PubMed1970

WHO collaborative study on the sero-epidemiology of rubella in Caribbean and Middle and South American populations in 1968.

Knowledge of the rubella antibody profiles of female populations of various ages and in various geographical areas is essential for an intelligent and effective administration of rubella vaccine. The investigation reported was undertaken to extend a previous WHO collaborative study to include additional areas of the Americas. As in the other mainland areas included in the earlier study, the presence of rubella haemagglutination-inhibiting antibody was found to be a likely event in over 80% of the females of child-bearing age in Argentina, Brazil, Chile, urban Peru (Lima) and Uruguay. Antibody rates were significantly lower in Jamaica, Panama, rural Peru and Trinidad. These data confirm and extend earlier findings of low levels of rubella immunity in certain island or isolated populations.

Adolescent↗
PubMed1967

Radiotherapy in the management of leukemia.

Localized radiation therapy directed to the spleen and other sites, supplemented by a whole-body radiation technique, appeared to increase survival time in the chronic leukemias. In recent years the alkylating drugs have provided a more convenient form of "whole-body effect", because treatment can be taken at home and yet observation maintained.Small or medium field radiation therapy remains the most efficient means of controlling localized leukemic infiltrations. Splenic irradiation has been used successfully in the control of hemolytic anemia occurring during the course of chronic leukemia where steroids have failed.Proper management of the leukemias requires close co-operation between the radiotherapist, internist and hematologist.

Humans↗
PubMedDate not supplied

Salmon pancreatic polypeptide exhibits neuropeptide Y-like activities in rats.

Salmon pancreatic polypeptide (sPP) is a 36 residue peptide amide isolated from salmon pancreas. It has 83% sequence identity with porcine neuropeptide Y (NPY). To confirm the sequence and obtain sufficient quantity of peptide for biological investigations, sPP was synthesized by automated t-Boc solid phase synthesis. The purified product had the expected amino acid composition, primary structure and mass, and was chemically and biologically indistinguishable from natural sPP. Investigation of its biological properties revealed that, like NPY, sPP increased blood pressure and decreased heart rate in anesthetized rats in a dose-dependent manner. There was no significant difference in the responses of NPY and sPP. Furthermore, administration of sPP directly into the hypothalamus of rats induced a feeding response comparable to that induced by NPY. Based on these investigations it may be suggested that synthetic and natural sPP are identical, and that sPP can express NPY-like activities in mammals presumably by interacting with the receptors of NPY.

Amino Acid Sequence↗
PubMedDate not supplied

Alterations in flash evoked potentials (FEPs) in rats produced by 3,3'-iminodipropionitrile (IDPN).

3,3'-Iminodipropionitrile (IDPN) is a neurotoxicant that produces changes in flash evoked potentials (FEPs) 18 weeks after treatment. We examined dose- and time-related effects of IDPN on FEPs at earlier time points than previously studied (52). Adult male Long-Evans rats were given IDPN (0, 100, 200, 400 mg/kg/day x 3 days, i.p.) and FEPs were recorded 14 days later. IDPN (400 mg/kg/day) decreased the amplitudes of some of the "early" and "middle" FEP peaks (n30 and N56), and increased the latencies of some early peaks (P21 and P46). A separate group of rats was treated with IDPN (0 or 400 mg/kg/day x 3 days, i.p.) and FEPs were recorded 1, 3, 7, 14, and 35 days later. The latencies of of all portions of FEPs were increased by IDPN, with maximal changes occurring at 7 and/or 14 days. The amplitude of the middle portions of FEPs (peaks N56, P63, N70, P90) were altered as early as day 3, and some changes were observed up to day 14. In contrast, the "late" portion of FEPs (peak N160) was affected at later times (days 14 and 35). Corneal opacities were noted on days 3 and 7, but were largely reversible by day 14. In the time-course study, IDPN decreased colonic temperature on days 1, 3, 7, and 14. The present results suggest that IDPN alters both the early FEP peaks related to the initial afferent sensory volley, and cortical processing associated with the middle and later portions of FEPs.

Animals↗
PubMedDate not supplied

Forty years on--contact tracing in Wakefield.

An audit of contact tracing activity for a range of common sexually transmitted diseases (STD) was performed prospectively on 100 consecutive referrals to the health advisers at the Genitourinary Medicine (GUM) clinic in Wakefield. Targets for contact attendance were set according to the initial index patient diagnosis. Health adviser contact tracing methods (telephone, letter, visit) were logged. A total of 119 contacts were identified; of these, 86 (73%) were seen and examined. Attendance within the target time of one working week was not achieved in gonorrhoea contacts, but 61% warts contacts attended within the target of 4 weeks. Tracing by patient-carried contact slips after interview with the health adviser was effective in the majority (68%) of notifications.

Adolescent↗
PubMedDate not supplied

Three cheers for conflict!

Conflict is pervasive and an inevitable part of life--at work and elsewhere. But author Dennis King, organizational consultant for The Procter & Gamble Manufacturing Company, adds that it is also a functional part of the social process. Managing conflict on the job involves the ability to identify, seek out, and utilize the functions of conflict and its outcomes. He identifies fifteen functions of conflict in three major categories: maintaining or reinforcing identity and innate strength, increasing operational effectiveness, and dealing with others. For example, conflict can lead to minor clashes that actually strengthen a relationship because they function as safety valves--preventing the buildup of tension to the stage of explosion. (Note, however, that a conflict over the basic foundation of a relationship spells trouble.) Similarly, in the union-management relationship, both negotiations and grievance handling focus on adjusting or eliminating problem elements so that the employer-employee relationship can exist satisfactorily. Recognizing and exploiting the functions of a conflict situation--that is, functional conflict management--can work to our benefit. If we develop a "functional mind-set," looking for the positive aspects of conflict will become natural.

Conflict, Psychological↗
PubMedDate not supplied

An analysis of the geographic variation in cancer incidence and its determinants in Ontario.

Cancer incidence data for the Ontario Public Health Units in 1980-91 were examined to investigate regional patterns and the existence of outlier values after adjustment for known risk factors. Candidate risk factors were derived from the Ontario Health Survey and the census. Weighted regressions were fit to the data, and the spatial pattern of the residuals was analyzed. The number of outlier data points with significant elevations or reductions in risk was close to that expected by chance. They were dispersed geographically, and occurred in a variety of cancer types. We conclude that, in general, most of the geographic variation in cancer risk can be associated with variation in known risk factors, and that there appear to be no broad regional effects remaining after adjustment for these factors. A few cancer sites provide limited evidence of regional effects that may warrant further investigation.

Adolescent↗
PubMedDate not supplied

Ectopic pancreas and the islet cell dysmaturational syndrome.

Two cases of ectopic pancreas are described in the setting of the islet cell dysmaturational syndrome. Microscopic and immunostaining studies revealed both lesions to be composed of primarily (80 percent to 90 percent) islet tissue with nuclear hyperchromasia and probable depletion of immunoreactive insulin in one case. Persistent hyperinsulinemic hypoglycemia required a second laparotomy with resection of ectopic pancreas in one case. Awareness of the phenomenon led to successful identification and resection of ectopic islet tissue on first surgery in a subsequent case. Ectopic pancreas is a relatively common developmental pancreatic anomaly, and knowledge of its potential contribution to life-threatening hypoglycemia may obviate the need for multiple surgeries in some cases of islet cell dysmaturational syndrome.

Choristoma↗