Biomedical subjects

O Llanos

Publications and source records attributed to O Llanos.

At least 19 recordsLinked to original sources

PubMed1992

Axonal sprouting induced in the sciatic nerve by the amyloid precursor protein (APP) and other antiproteases.

Protease inhibition is the mechanism by which some trophic factors promote the extension of neurites. In the rat sciatic nerve, we assessed the ability to induce sprouts of the APP isoform that embodies the Kunitz antiprotease domain and other antiproteases. With the electron microscope, axonal sprouts were found when antiproteases were supplied but not after administration of inactive substances. We conclude that axons have a drive to sprout which can be released by the unbalance of an extracellular protease-antiprotease system. We propose that this system is involved in the pathogenesis of Alzheimer's disease.

Amyloid beta-Protein Precursor↗

PubMed1992

[Treatment of non-variceal upper digestive hemorrhage with endoscopic thermocoagulation].

Over a year period, 60 of 172 patients presenting with upper gastrointestinal bleeding were treated by endoscopic thermocoagulation. Entry criteria included active bleeding (pulsatile or oozing), a visible vessel, sentinel clot or the presence of a pigmented protuberance at the ulcer crater. Hemostatic therapy was performed using the heat probe. The physical status and risk of the patients was estimated according to the ASA classification. Hemostasis was obtained in 17 of 21 patients with pulsatile bleeding (81%), 30 of 30 patients with oozing (100%) and 18 of 18 patients with a visible vessel or a pigmented protuberance in the lesion (100%). Three patients, older than 70 years of age, died. All had pulsatile bleeding from a deep ulcer located at the posterior-inferior wall of the duodenal bulb. They were classified as ASA III (n = 1) or IV (n = 2) with significant concomitant illness. These results suggest that endoscopic thermocoagulation is an effective treatment of active upper gastrointestinal bleeding, especially useful in a group of high risk patients.

Adult↗

PubMed1991

[Regeneration of gastric mucosa after endoscopic biopsy].

Eleven gastric mucosal defects produced by endoscopic biopsy in non-tumoral areas were histologically studied in gastrectomy specimens. The biopsies had been performed from one up to seven days before the operation. The base of each defect was formed by submucosa infiltrated by erythrocytes, fibrin and neutrophils, which were later replaced by small blood vessels, fibroblasts and collagen fibrils. The mucosa of the margins bowed down towards the base of the defect. This marginal mucosa showed dedifferentiation of the glandular epithelial cells, increased mitotic index and some cystic glandular structures lined by basophilic cells. The defect was progressively covered by a layer of flattened or cuboidal cells in which no mitoses were observed; their cytoplasm contained mucosubstances similar to those of the superficial epithelium of the remaining mucosa, either foveolar- or intestinal metaplastic-type. From this layer, simple gland-like invaginations to the underlying connective tissue were observed. The findings are consistent with the regenerative events described in experimental gastric ulcers in animals. The method employed may be useful to study specific aspects on the regeneration of the human gastric mucosa.

Biopsy↗

PubMed1991

[Acute severe pancreatitis. Analysis of mortality and morbidity].

Sixty-three patients with severe acute pancreatitis have been studied. Pancreatitis was associated with biliary tract disease in 23 patients (36.5%) and with alcoholism in 21 (33.3%). It occurred post-operatively in 9, and was associated with other conditions in 10. We evaluated the Ranson prognostic signs (RPS) with the appearance of complications. 36 patients (57.2%) had 3-4 RPS, 9 (30.2%) had 5-6 RPS and 8 (12.6%) had 7 or more RPS. Diagnostic laparotomy was performed in 11 patients (17.5%). 55 patients were operated one or more times due to failure of medical treatment and/or local and septic complications. The most frequent complications were pancreatic abscess (60.3%), sepsis (58.7%) and pulmonary insufficiency (52.4%). Renal failure occurred in 26 patients and 9 required dialysis. Of the patients with renal failure, 84.6% (22/26) had 4 or more RPS; 78.4% (29/37) of those with sepsis and 71.6% (27/38) of those with pancreatic abscess also had 4 or more RPS. The mean duration of hospitalization of survivors was 58 +/- 30 days. Overall mortality was 28.6%. We conclude that RPS are helpful to predict complications in patients with severe pancreatitis.

Acute Disease↗

PubMed1990

[The medical treatment of intestinal obstruction due to adhesions and adherences].

Adhesions are the most common cause of intestinal obstruction. Medical treatment for those patients with no signs of vascular involvement has been successful in many cases. We reviewed the clinical records of 87 patients with intestinal obstruction due to adhesions, having a total of 122 episodes. Satisfactory follow up was obtained in 76% of patients for a mean of 29.6 months. 47% of episodes resolved without need for surgical intervention. Volume entrapment during the first hours was correlated with need for surgical treatment (p < 0.01). Recurrences were not different between medical and surgical patients (p = 0.28). Thus, medical treatment of this type of intestinal obstruction may be attempted in most patients, not only those who are poor surgical risks.

Adult↗

PubMed1989

[Colorectal cancer: follow-up after curative resection].

From Jan 1978 to Dec 1984, 128 patients had a curative resection of colorectal carcinoma. A program for early detection and surgical correction of recurrences was initiated in 88 patients with a mean age of 61 years (range 24 to 85). Seventy two patients complied with the program involving clinical examination, chest X-ray, alkaline phosphatase and CEA determinations and endoscopy at 6 month intervals. Mean follow up was 36 months (range 6 to 60). A total of 28 recurrences (32%) were detected: 4 local, 17 distant and 7 local and distant. Recurrences occurred in 46% of grade C, 19% of grade B and 0% of grade A lesions. Sixty eight% of recurrences were detected within 12 months and 93% within 36 months after surgery. Recurrences were detected by clinical examination in 71% of cases. CEA determination was sensitive (81% and specific (92%) for detection of recurrences in the remaining patients. Four patients (14%) were reoperated on with a survival of 3 to 26 months, all dying from disseminated disease. We conclude that this program did not help to improve the 5 year survival rate of colorectal carcinoma submitted to curative resection. CEA determination may be indicated at 2 month intervals during the period of increased recurrence risk.

Adult↗

PubMed1989

[Value of preoperative colonoscopy in colon-rectal neoplasms].

The surgical approach to treat colo-rectal carcinoma is usually based on the findings of barium enema. In 102 patients we reviewed the yield of pre-operative colonoscopy. Barium enema revealed the cancer in 76 of 84 patients (91%), whereas colonoscopy did so in 96 of 102 subjects (94%). In addition, 5 associated cancerous lesions were demonstrated by colonoscopy and none by barium enema. Associated benign lesions were seen in 14 patients. In 5 patients the surgical plan based on the barium enema was modified by the findings at colonoscopy. Eight false negatives to barium enema were correctly diagnosed by colonoscopy. We conclude that colonoscopy yields valuable information, beyond that of barium enema, in patients with colo-rectal cancer.

Adult↗

PubMed1989

[Duodenal obstruction caused by cholelithiasis (Bouverets' syndrome): a clinical case].

A 55 year old man presented with vomiting, abdominal pain, diarrhea, jaundice and choluria. An obstruction of the gastric outlet by a large gallstone located at the duodenum was demonstrated by radiologic, ultrasonographic and endoscopic examinations. The stone could not be removed through endoscopy and the patient was successfully operated on. A review of published reports is included.

Cholelithiasis↗

PubMed1989

[Splenic abscess].

Splenic abscess is an uncommon condition associated with a high mortality. In most cases an hematogenous focus can be identified. Early diagnosis is essential for recovery. CT scan and ultrasound tomography are the best diagnostic tools. The latter was used to establish the diagnosis in 2 patients who were successfully treated by surgery.

Abscess↗

PubMed1989

[Gastric cancer: surgical results and survival].

From 1975 to 1984, 292 patients with gastric cancer were treated according to a prospective and standardized surgical protocol. This series included 195 men and 97 women, with an average age of 62.5 +/- 11 years (SD). In 20 patients (6.8%) surgery was not performed and 99 were considered unresectable at laparotomy. Gastric resection was performed in 173 (63.3%) (distal subtotal gastrectomy in 94 and total gastrectomy in 79). Operative mortality for subtotal gastrectomy was 3.1% and 6.3% for total gastrectomy. Early gastric cancer was found in 21 patients (none presented lymph node metastases). The cancer invaded the muscular layer in 18 (31% with lymph node metastases) and reached beyond the muscular layer in 134 patients (60.8% with lymph node metastases). The five year actuarial survival was 0% in patients who did not undergo gastric resection, 35.5% for those patients with tumor invading the serosal layer or beyond who were resected, 56.5% for those with invasion up to the muscular layer and 91.8% for patients with early gastric cancer. For those patients who underwent a curative resection, actuarial five year survival was 81%.

Actuarial Analysis↗

PubMed1988