Biomedical subjects

C V Godellas

Publications and source records attributed to C V Godellas.

4 recordsLinked to original sources

PubMed1995

The identification and mapping of melanoma regional nodal metastases: minimally invasive surgery for the diagnosis of nodal metastases.

The most controversial part of melanoma surgical care involves the role of elective lymph node dissection (ELND). Whereas proponents cite retrospective studies demonstrating the ability to control regional metastases and more accurate staging, opponents cite the unnecessary morbidity of a complete node dissection for the majority of patients. The technology of sentinel node mapping and selective lymphadenectomy, defined as the identification and removal of the first node into which the primary melanoma drains, may revolutionize melanoma care. If the sentinel node is negative, then theoretically the remainder of the nodes should also be negative (no "skip" metastases), and a complete lymphadenectomy would not be required to control occult nodal disease. The location of the sentinel node may be variable in the lymphatic basin. Ideally, the surgeon needs a map of the position of the sentinel node in reference to the other nodes in the basin in order to do the procedure under local anesthesia with small incisions. In this way, patients are subjected to minimal morbidity and the procedure can be performed as an out-patient. Twenty-nine patients with clinically negative nodes and melanomas greater than 0.76 mm in thickness were judged to be candidates for ELND. Preoperative lymphoscintigraphy in two planes was used to mark the sentinel node, and the patients were taken to the operating room for intraoperative lymphatic mapping and sentinel node biopsy followed by complete dissection.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1992

Hepatic function after porto-systemic shunt.

Advanced hepatic injury can be identified by the appearance of jaundice, coagulopathy, or encephalopathy but these conditions are late, irreversible findings and represent the end stage of a long insidious process. Currently available methods for assessing "liver function" (SGOT, SGPT, GGT, LDH, etc.) do not actually measure liver function. In this study we prospectively evaluated "true" liver function in patients undergoing porto-systemic shunt. Effective hepatic blood flow [low dose galactose clearance (EHBF)], hepatocyte transport (theophylline levels at 24 hr), and hepatic conjugation ability [acetaminophen metabolism to its glucuronide and sulfate conjugates ( (S + G)/A) and acetaminophen remaining at 24 hr (A24)] were measured in normal males (NL) and in patients pre- and post-8-mm H-graft portacaval shunt (PCS). All data are means +/- SEM, analyzed by Student's t test, and significance was accepted if P less than 0.05. There were no significant differences in EHBF even after PCS. Hepatocyte transport was decreased in pre-op (1.43 +/- 0.16 vs 0.74 +/- 0.08) and post-op (1.79 +/- 0.34) PCS patients. Hepatic conjugating ability was also decreased in pre-op PCS patients [A24 was increased (0.24 +/- 0.11 vs 0.01 +/- 0.01) while the ratio of conjugation products to acetaminophen remained the same]. The ability of the liver to conjugate substrate was severely compromised postoperatively [A24 - 1.27 +/- 0.67, (S + G)/A - 1.19 +/- 0.34]. We believe that changes in liver function can be accurately measured using these noninvasive methods, and in using these methods we have identified altered hepatocyte transport and conjugating ability in patients undergoing porto-systemic shunt surgery.

Acetaminophen↗

PubMed1991

Atrial natriuretic factor: a possible new gastrointestinal regulatory peptide.

Although associated primarily with the cardiovascular system, atrial natriuretic factor (ANF) has been found to increase the magnitude of duodenal contractions and may play a role in salt and water absorption across gastrointestinal epithelium. Because secretory diarrhea and increased peristalsis are commonly associated with conditions related to hypergastrinemia, we examined an animal model of hypergastrinemia (fundusectomy) to evaluate a possible role for ANF. Sprague-Dawley rats underwent either fundusectomy or sham operation. Circulating levels of gastrin (1085 +/- 105 vs 59 +/- 5 pg/ml), ANF (209 +/- 50 vs 59 +/- 10 pg/ml), and pro-ANF 1-98 (786 +/- 80 vs 599 +/- 49 pg/ml) were elevated significantly 3 months after fundusectomy versus control animals. The increased levels of ANF and pro-ANF 1-98 correlated with the increased gastrin levels (p less than 0.05). Tissue content of ANF and pro-ANF 1-98 were determined at sequential sites in the stomach and small intestine. In normal rats ANF concentrations were greatest in the small intestine; pro-ANF 1-98 content was similar in all tissues except ileum (increased). In rats that underwent fundusectomy, ANF and pro-ANF 1-98 were markedly increased in duodenum compared with all other tissues. Only duodenum showed a difference in peptide levels between normal rats and rats that underwent fundusectomy, (ANF, 1.5 +/- 0.5 vs 16.7 +/- 2.3 ng/gm; pro-ANF 1-98, 0.6 +/- 0.3 vs 51.2 +/- 36.1 ng/gm). Circulating ANF and pro-ANF 1-98 are increased in rats that have undergone fundusectomy. Our results suggest that duodenum may be the source of these increased levels.

Animals↗

PubMed1990

Posttranslational gastrin processing depends on tumor morphology.

Extracellular matrices have recently been demonstrated to alter cell morphology in culture. Altered cell morphology has been associated with changes in gene transcription and translation, but it is not known whether it also affects posttranslational processing. Using tyrosine-O-sulfation as a marker of processing, we studied the effects of various substrates on biologically active gastrin (IRG) production and sulfation in gastrin-containing tumor cells (GT cells). Dispersed GT cells were plated onto different substrates and then incubated. Culture media from days 4, 7, and 28 were assayed with specific antibodies that recognize total IRG and nonsulfated IRG. Cells cultured on plastic and dried films of laminin, collagen, and Matrigel (Collaborative Research Inc., Lexington, Mass.) flattened and formed monolayers of GT cells. Cells cultured on a porous membrane and hydrated gels of collagen and Matrigel did not flatten but formed spheroids of GT cells. The monolayer cultures showed an increase in sulfation with time but a decrease in IRG production. The spheroid cultures maintained a constant level of sulfation over time and, with the exception of Matrigel (gel), also showed a decrease in IRG production. These results indicate that the level of sulfation was unchanged from that of the original tumor when cells were grown in spheroids but increased when cultured as monolayers. It appears that alteration of the cellular milieu alters colony morphology, which in turn alters gastrin processing.

Cell Survival↗