Biomedical subjects

J P Paredes

Publications and source records attributed to J P Paredes.

4 recordsLinked to original sources

PubMed2006

Increased response to morphine in mice lacking protein kinase C epsilon.

The protein kinase C (PKC) family of serine-threonine kinases has been implicated in behavioral responses to opiates, but little is known about the individual PKC isozymes involved. Here, we show that mice lacking PKCepsilon have increased sensitivity to the rewarding effects of morphine, revealed as the expression of place preference and intravenous self-administration at very low doses of morphine that do not evoke place preference or self-administration in wild-type mice. The PKCepsilon null mice also show prolonged maintenance of morphine place preference in response to repeated testing when compared with wild-type mice. The supraspinal analgesic effects of morphine are enhanced in PKCepsilon null mice, and the development of tolerance to the spinal analgesic effects of morphine is delayed. The density of mu-opioid receptors and their coupling to G-proteins are normal. These studies identify PKCepsilon as a key regulator of opiate sensitivity in mice.

Animals↗

PubMed1994

[Colostomy closure: is it an intervention without risk?].

OBJECTIVE: To examine whether colostomy closure is an operation with a high risk of complications. DESIGN: Retrospective study of colostomy closures in a 14-year period. PARTICIPANTS: 60 patients, averaging 54 years, males in 63%. The main indication for colostomy was colorectal neoplasm (47%), followed by trauma (23%). RESULTS: There were 15 Hartman's procedure reconstructions, 4 reconstructions of colostomy and mucous fistula, and 41 "simple" colostomy closures. The closure was extraperitoneal in 40%, suturing only the anterior colonic wall in 42%. We had 27 postoperative complications in 33% of the patients, without mortality. The average hospital stay was 8 days longer in the group with complications. The complication rate was 29% in the "simple" closure versus 42% in the reconstruction group (this difference was not statistically significant). The statistic analysis (chi-square and Mann-Whitney tests) showed no influence on morbidity of factors such as age, sex, previous disease, age of colostomy, and type and closure technique of colostomy. CONCLUSIONS: Colostomy closure has a high rate of postoperative complications (33%). These are minor in almost all cases, without mortality.

Adult↗

PubMed1992

[An experimental evaluation of a splenic autograft in the greater omentum].

This report comprises a study of splenic autotransplantation in omental pouches in rats. Twenty six rats were operated. The spleen (50%) was transplanted after splenectomy in four different fragments. The animals were re-explored after periods between 3 and 5 1/2 months and the splenic implants retrieved for histological examination as well as size and weight evolution. In 25/26 animals a viable spleen was identified. The mean weight of the retrieved spleen fragments was 150 mg versus 525 mg weight of the implanted materials. In no case there was an increase in size of the implanted fragments. Fifty-two of the 104 implanted fragments were retrieved with weight increase in 8.65% of them.

Animals↗

PubMed1990

Variations in sensitivity after sectioning the intercostobrachial nerve.

The authors present a prospective study of the variations in sensitivity that appear in the armpit and arm after the intercostobrachial nerve has been sectioned in a modified radical mastectomy. Of a total of 208 patients studied between 1978 and 1987, the intercostobrachial nerve was sectioned in 139 patients, whereas in 30 it remained intact; in 39 patients only peripheral branches of the nerve were sectioned. The patients were examined at regular postoperative intervals in order to evaluate their sensitivity both to touch and to pain in the axilla and arm. Four hundred thirty-three examinations were carried out and the 3 operative groups were assessed accordingly. After the nerve was sectioned, there was increasing anesthesia in the armpit and hypoesthesia on the posterointernal face of the arm, while for the patients in whom the intercostobrachial nerve remained intact, these alterations were less intense and long-lasting. Significant statistical differences between the two groups also exist. In the absence of axillary lymphatic ganglia infiltrated by the tumor, the conservation of the intercostobrachial nerve is recommended.

Arm↗