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Biomedical subjects

L Herrera

Publications and source records attributed to L Herrera.

At least 181 records · Page 10Linked to original sources
PubMed1985

Metastasis to the parotid gland from colorectal adenocarcinoma.

This manuscript presents only the fifth reported case in the literature of colorectal carcinoma with metastasis to the parotid gland. A 66-year-old white woman, referred to Roswell Park Memorial Institute, presented with a left parotid mass and a past history of undergoing right hemicolectomy for an adenocarcinoma of the ascending colon with synchronous liver metastases. The clinical presentation and treatment of the patient are discussed with a review of the literature.

Adenocarcinoma↗
PubMed1985

Ileal conduits for recurrent unresectable colorectal adenocarcinoma.

In a retrospective 4 year study, 19 patients with unresectable recurrent pelvic tumor secondary to colorectal adenocarcinoma underwent urinary diversion. An ileal conduit was performed for palliative purposes at the time of exploration. None of the 19 patients had evidence of distant metastases. Survival after the ileal conduit ranged from 2 to 26 months (median 13 months). This survival rate did not vary significantly according to sex or whether hydronephrosis resolved after urinary diversion. Postoperative complications developed in three patients. Two of these complications were ureterointestinal anastomotic leaks and the third was development of an enterocutaneous fistula. The quality of life was rated as good by 75 percent of the patients and fair by 18 percent, with all patients relieved of painful obstructive uropathy. Eighteen of 19 patients were able to resume useful and productive lives.

Adenocarcinoma↗
PubMed1985

Pelvic and perineal recurrences after abdominoperineal resection for adenocarcinoma of the rectum.

Pelvic and perineal recurrences were evaluated in 48 patients who underwent abdominoperineal resection at Roswell Park Memorial Institute for adenocarcinoma of the rectum. The duration of follow-up of these patients was at least 5 years or until death. There were 26 male and 22 female patients with a median age of 60 years. In 40 patients, the abdominoperineal resection was considered to be curative and in the remaining 8 patients, palliative abdominoperineal resection was performed. Only 2 of the 48 patients had a pelvic recurrence and in none of these patients was this recurrence the first site of relapse. One of the 48 patients had a local perineal recurrence; however, this was treated successfully with surgery. This represents a total of three pelvic or perineal recurrences in 48 patients, for a recurrence rate of 6 percent.

Abdomen↗
PubMed1985

Hepatic resection for isolated metastasis from colorectal carcinoma.

Surgical results were analyzed in 36 patients who had undergone hepatic resection for metastases from colorectal carcinoma. Survival was not altered by the type of surgical resection nor in the presence of solitary compared with multiple lesions. No difference in survival from the time of liver resection was noted in patients staged as Dukes' B and Dukes' C (metachronous liver metastasis) in comparison to patients who presented with synchronous liver metastases. Overall median survival was 22 months with no 5 year survivors to date. There is a tendency for recurrence to occur in extrahepatic sites, which emphasizes the need for an effective chemotherapeutic agent.

Actuarial Analysis↗
PubMed1985

Quality of life.

Explore the source record for details and available documents.

Humans↗
PubMed1984

Metabolic imbalance in a Saccharomyces cerevisiae mutant unable to grow on fermentable hexoses.

A mutant of Saccharomyces cerevisiae unable to grow on fermentable hexoses has been studied. The mutant grew normally on galactose or maltose. It was also able to grow on a medium containing glucose or fructose with a 25-fold excess of D-xylose. Assay of the glycolytic enzymes in vitro did not show differences between the parental and the mutant strains. Upon addition of fructose, metabolites up to triose phosphates accumulated and the ATP dropped to low levels. It is proposed that an imbalance between the initial and final segments of glycolysis that depletes the cell of ATP produces the observed phenotype.

Adenosine Triphosphate↗
PubMed1984

Cavernous hemangioma of the anus.

Vascular tumors of the large bowel can be divided into malignant and benign lesions. The benign lesions can be divided into capillary and cavernous hemangiomas. Large-bowel hemangiomas are rare lesions, with the majority of cases reported in the rectum and rectosigmoid regions. Few cases of isolated anal hemangiomas are found in the literature. A case of an asymptomatic anal cavernous hemangioma, palpable on routine rectal examination and subsequently removed at proctosigmoidoscopy, is described.

Aged↗
PubMed1984

Endobronchial metastasis from colorectal carcinoma.

A case report and review of the literature concerning endobronchial metastasis from colorectal carcinoma is discussed. Careful attention to the past history of the patient, presenting symptoms and laboratory evaluation, may lessen the diagnostic difficulty in differentiating a centrally located bronchogenic carcinoma from a metastasis to a major bronchus. In the majority of cases, the primary colorectal tumor will precede the pulmonary abnormality. The most frequently manifested symptoms are cough and hemoptysis. Radiologic findings usually consist of a collapsed lung, lobe or segment secondary to the bronchial obstruction. There appears to be equal predilection for metastatic involvement of either the right or left bronchial segments. Bronchial biopsies and comparison with the previous histology of the primary colorectal tumor are mandatory.

Adenocarcinoma↗
PubMed1984

Lysolecithin:lysolecithin acyltransferase from rabbit lung. A conformational study.

The enzyme lysolecithin:lysolecithin acyltransferase from rabbit lung has been found to have a relatively disordered conformation in solutions of high ionic strength. The protein exhibited an ordering of structure when salt was suppressed. This conformational change was concomitant with the loss of transacylase activity, the hydrolytic reaction remaining unchanged. Addition of NaCl caused a progressive disordering of structure with a parallel increase of transacylase activity. The acid denaturation of the protein, at low and high ionic strengths, showed that the ionization of groups with pK in the range 5.9-6.4 was essential for denaturation. The structure was stable at basic pH. The addition of lipids resulted in a non-specific stabilization of the disordered conformation, in the same manner as the addition of NaCl. From these results, it is suggested that there are two conformations for this protein which differ in their ability to bind lysolecithin molecules in the enzyme deacylation step of the reaction. This hypothesis agrees with previously published properties of the enzyme, concerning aggregation with other proteins and kinetic data. From the amino acid composition and conformational properties, the authors suggest that this enzyme could be a peripheral membrane protein.

1-Acylglycerophosphocholine O-Acyltransferase↗
PubMed1984

Phase I-II trial of high-dose calcium leucovorin and 5-fluorouracil in advanced colorectal cancer.

Twenty-six patients with metastatic colorectal adenocarcinoma were entered into a Phase I-II study of 5-fluorouracil (5-FUra)-high-dose leucovorin (CF). The starting dose of 5-FUra was 300 mg/sq m with escalation to 750 mg/sq m/week in 6 doses given by rapid i.v. injection midway during a 2-hr infusion of CF, 500 mg/sq m. Partial responses were seen in 9 of 23 patients (6 of 12 who had had previous 5-FUra). Complete normalization of liver enzymes was seen in two of these patients. Side effects were seen sporadically with 5-FUra doses up to 600 mg/sq m. At a 600-mg/sq m 5-FUra dose, 8 of 18 patients had diarrhea, and 2 of 18 had white blood cell counts less than 3000/microliter. At a 750-mg/sq m dose of 5-FUra, 6 of 11 patients had severe diarrhea and 6 of 11 had white blood cell counts less than 3000/microliter. Other toxicities were mild conjunctivitis and lacrimation, thinning of the nails, and alopecia. In bioavailability studies of CF p.o., no plasma CF could be detected. After CF i.v., mean plasma peak was 111.3 +/- 40.3 (S.D.) microM. 5-FUra-CF appears to be effective in patients clinically resistant to 5-FUra. This study is being extended to randomized trial of 5-FUra-CF versus 5-FUra alone.

Adult↗
PubMed1982

Methionine degradation in Candida utilis.

Incubation of cell-free extracts of C. utilis and its ethionine-resistant mutants with methionine, aspartate and alanine, and with various acceptor oxo-acids showed the presence of several transamination activities (Glu-Asp, Ala-Glu, Met-Glu, Met-Ala, Ala-Asp, but not Met-Asp). The lack of utilization of methionine by mec mutants appears to be due to a transport lesion.

Biological Transport↗
PubMed1982

Modification of phrenic nerve output to hypoxia after two hours of hypercapnia and increased cerebrospinal fluid [HCO3-].

Decreased ventilatory response to hypoxia has been reported in patients with CO2 retention. The CO2 retention increases cerebrospinal fluid (CSF) [HCO3-], which could modify the ventilatory response to hypoxia. In order to evaluate the effect of increased CSF [HCO3-] as a consequence of hypercapnia on the response to hypoxia, phrenic nerve output during 5 min of progressive hypoxia was measured in anesthetized vagotomized and mechanically ventilated dogs when their acid-base was normal and when CSF [HCO3-] had increased. Peak phrenic nerve activity (PPNA), inspiratory time (TI), and expiratory time (TE) were recorded in 2 groups of dogs. Two hypoxic tests were conducted 2.5 h apart in each group. One group had normal acid-base status and the second group after the first hypoxic challenge breathed 10% CO2 for 2 h, and then ventilation was adjusted to bring CSF pH back to normal. The CSF [HCO3-] then had increased by 5.2 mEq/L and CSF PCO2 was 14.6 mmHg higher. With CSF [HCO3-] elevation, PPNA activity in response to hypoxia was significantly depressed, compared with that in animals with normal acid-base balance, TI was increased indicating slowing of nerve discharge, and TE was minimally increased indicating lessening of frequency of neural bursts. We conclude that the metabolic component of acid-base balance in the central nervous system can influence the neural output of the respiratory centers in response to hypoxia as manifested by phrenic nerve output, and increased CSF [HCO3-] seen with hypercapnia is associated with depressed hypoxic response.

Animals↗
PubMed1981

Use of permeabilized yeast cells as a system of enzyme immobilization. Its use for the preparation of mannose 6-phosphate.

It was shown that hexokinase contained inside permeabilized yeast cells can be used successfully in the phosphorylation of mannose for the production of mannose 6-phosphate. We propose that enzymes entrapped within the semipermeable cell membrane be considered as an extension of the enzyme immobilization concept, since it shares many of its advantages and several of its properties with some unique characteristics.

Cell Membrane↗
PubMed1980

CSF bicarbonate regulation in metabolic acidosis: role of HCO3- formation in CNS.

In metabolic acidosis, cerebrospinal fluid bicarbonate content (CSF [HCO3-]) falls in parallel with reductions in CSF CO2 tension (PCO2), and the fall is minimal with isocapnia. Regulation of CSF HCO3- was therefore investigated during 6 h of isocapnic metabolic acidosis in dogs. One group received intraventricular injections of acetazolamide to inhibit the centrally located carbonic anhydrase, essential in central nervous system (CNS) HCO3- formation, while the control group received intraventricular saline. Plasma [HCO3-] was reduced by 10 meq/l with iv infusion of 0.2 N HCl. CSF [HCO3-] fell in the control group from 22.8 to 17.7 meq/l at 6 h, whereas in the acetazolamide group it fell from 22.9 to 13.0 meq/l. Brain ammonia content was 1,286 +/- 153 microgram/100 g in the controls and 666.2 +/- 103 microgram/100 g in the acetazolamide-treated group at 6 h. Therefore, some reduction in CSF [HCO3-] occurred during 6 h of isocapnic metabolic acidosis along the chemical concentration gradient between CSF and blood, but further falls, in CSF [HCO3-] were minimized by de novo, carbonic anhydrase-dependent HCO3- formation within the CNS. Some of H+ formed were buffered by the increase in brain ammonia. These central mechanisms contribute to local CNS H+ homeostasis in metabolic acidosis.

Acetazolamide↗
PubMed1980

Mucinous cystic neoplasm of the pancreas demonstrated by ultrasound and endoscopic retrograde pancreatography.

Mucinous cystic neoplasms of the pancreas are rare lesions. They may undergo subclinical malignant transformation; hence, establishment of the diagnosis prior to surgical exploration is of great importance. The case herein reported is of interest because the use of endoscopic retrograde pancreatography and ultrasound strongly supported a clinical suspicion of a true cyst of the pancreas. It also represents the second case reported studied by these diagnostic modalities.

Adult↗