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Biomedical subjects

J Conn

Publications and source records attributed to J Conn.

At least 19 recordsLinked to original sources
PubMed1992

A polytene chromosome study of four populations of Anopheles aquasalis from Venezuela.

Polytene chromosome studies were undertaken to elucidate taxonomic relationships among populations of Anopheles aquasalis and A. emilianus in Venezuela. Four collection sites were chosen: two in Sucre state (Santa Fe and Guayana) where A. aquasalis (considered to be A. emilianus by Gabaldón and Escalante) is presumed to be the major regional vector of Plasmodium vivax; and two in areas where no malaria transmission occurs (Caño Rico, Aragua state, and Puerto Cabello, Carabobo state). The chromosome banding pattern of the four populations was identical and conformed to the standard chromosome map of A. aquasalis from Brazil. These results suggest that the population from Santa Fe and Guayana, considered to be A. emilianus, is conspecific with A. aquasalis. However, its status as a distinct species with a homosequential polytene chromosome banding pattern cannot be ruled out.

Animals↗
PubMed1991

A cytogenetic analysis of the polytene chromosomes of Anopheles triannulatus (Diptera: Culicidae) from western Venezuela.

The larval polytene chromosomes of Anopheles triannulatus are described for the first time in this report. The population from western Venezuela was chosen arbitrarily as the chromosome standard and is the basis for the photomap presented here. Anopheles trannulatus displays whole-arm associations distinct from other members of the subgenus Nyssorhynchus that have been examined cytogenetically. The association pattern for An. triannulatus is 2R-3R and 2L-3L, rather than the more common 2R-2L and 3R-3L. The possible role of whole-arm translocations in speciation is briefly discussed.

Animals↗
PubMed1990

Chromosome key to the larvae of the Simulium metallicum complex (Diptera: Simuliidae) from Latin America.

A key based on larval salivary gland polytene chromosome inversions is presented for 11 members (species A-K) of the Simulium metallicum Bellardi complex from Latin America. Most members (B, D, E, G, H, I, J, and K) can be distinguished from the cytological standard, sibling A, solely on the basis of fixed inversion differences. A suite of characters (sex-linked inversions as well as polymorphisms) must be examined to separate cytotypes C and F from A.

Animals↗
PubMed1990

A genetic study of the malaria vector Anopheles nuneztovari from western Venezuela.

A photomap of larval polytene chromosomes of Anopheles nuneztovari (population B) from western Venezuela is presented. Samples of An. nuneztovari B taken from 4 study sites in the states of Barinas and Táchira comprise a single panmictic population, which is chromosomally identical to the cytotype identified by Kitzmiller et al. (1973) from western Venezuela and Colombia. The frequency of polymorphism 2La has increased significantly in the 16 years that have elapsed since the 1973 study. In addition, inversion 2La does not conform to Hardy-Weinberg equilibrium. These 2 changes are most likely due to environmental alterations which have resulted in the heterozygous condition becoming more locally adaptive.

Animals↗
PubMed1989

Is the time now?

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Delivery of Health Care↗
PubMed1988

Organized medicine.

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American Medical Association↗
PubMed1986

In vivo study of an antimicrobial surgical drape system.

We performed a double-blind clinical study to determine the efficacy of nonwoven laparotomy drapes in which 3-(trimethoxysilyl)propyldimethyloctadecyl ammonium chloride, an antimicrobial agent, was chemically bonded to the absorbent reinforcement surrounding the fenestration. The reinforcement portion of the surgical drape that contained the fenestration was segmented into four identical-appearing sections, two on each side of the fenestration. One segment on each side was antimicrobial. The locations of the treated segments were randomly varied. At the end of each operation, test strips were removed. Bacteria were harvested from each segment by mechanical agitation. Bacterial CFU were counted. There were 110 surgical cases in the study, including clean, clean contaminated, and contaminated procedures. Data analysis divided the cases into two distinct groups. Group 1 was composed of 59 cases in which less than 30 total CFU was recovered from the four test samples. The average duration of surgery for this group was 1.8 h. Group 2 was composed of 51 cases in which bacterial recovery was in excess of 30 CFU per procedure (range, 30 to 25,000 bacterial CFU). The average duration of surgery was 3.3 h. Bacterial reduction in the treated strips was 84%. The most common organisms identified on the laparotomy drapes were Staphylococcus epidermidis, S. hominis, and Micrococcus luteus. This study demonstrated that the reinforcement of a laparotomy drape is a reservoir for potential pathogens. It demonstrated that an organosilicon quaternary ammonium antimicrobial agent covalently bonded to the reinforcement reduced the number of potential pathogens surrounding the surgical incision by 84%, independent of the size of the bacterial challenge.

Anti-Infective Agents, Local↗
PubMed1979

Hemangiopericytoma. Literature review and clinical presentations.

Hemangiopericytomas are soft tissue sarcomas of vascular origin, comprised of pericytes. They have been reported in the extremities, head and neck, back, retroperitoneum, and abdomen. The criteria for the diagnosis and treatment are reviewed. Wide local ablation of the tumor is necessary to prevent local recurrence. Fifty per cent are malignant, although regional node spread is infrequent. Ultrastructural studies are necessary to differentiate hemangiopericytomas from other sarcomas. Long-term follow-up of all cases is essential for optimal clinical management.

Adult↗
PubMed1977

Intramural hematoma of the gastrointestinal tract.

Two hundred sixty cases of intestinal intramural hematoma and subsequent bowel obstruction have been reported in the world literature. These cases have been evaluated and seventeen additional cases are reported. Multiple etiologic factors are presented, with trauma and anticoagulant therapy being the most common. Barium x-ray examination is the single most reliable diagnostic study. The mode of therapy for intramural hematoma depends upon thorough evaluation of the patient. Patients on anticoagulant therapy are best treated by observation and cessation of anticoagulants. Should the patient fail to improve or become worse, then surgery may become necessary. When trauma is a factor, prompt operative intervention is indicated.

Abdominal Injuries↗
PubMed1977

Pancreaticoduodenal arterial aneurysms.

Experience with four aneurysms of the pancreaticoduodenal artery is reviewed and compared to the reported experience of 19 other cases. In view of the common presentation of such lesions as intra-abdominal hemorrhage preceded by non-specific abdominal pain and other digestive symptoms, it is suggested that angiography perfomed preoperatively or intraoperatively allows definitive diagnosis and leads to specific therapy.

Aged↗
PubMed1977

A study of polybutilate lubricated polyester sutures.

In the 49 patients in whom polybutilate coated polyester sutures were used, no adverse side-effects, such as increased redness, tenderness, pain or edema of the wounds, were noted. Primary healing was achieved in each patient. There were no suture related complications encountered during the early or late follow-up examinations. Polybutilate coated polyester sutures were found to be easy to work with. They were strong, pliable and handled and tied with ease. They had no tendency to twist, tangle or adhere to gloves or instruments. Tissue passage through skin, fascia, arteries, veins and Dacron vascular grafts was better than it was with uncoated polyester sutures and as good as with Teflon coated sutures. No unusual drag, pull or catching of the sutures was encountered. Over-all, the polybutilate coated polyester suture is thought to be a safe, reliable and an easy to use material for a wide variety of surgical procedures for which a strong nonabsorbable suture is indicated.

Adolescent↗