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Biomedical subjects

C Simopoulos

Publications and source records attributed to C Simopoulos.

At least 91 records · Page 5Linked to original sources
PubMed1985

[Secretion of gastric acid, gastrin and cyclic nucleotides in relation to the action of the vagus nerve].

Changes on levels gastric acidity, on serum gastrin, cAMP and cGMP levels were studied in 18 healthy volunteers after either stimulation (injection of 0.2 IU of soluble insulin/kg body weight to a group of 9 subjects) or stimulation and inhibition (injection of insulin plus atropine per os to the other group of 9 subjects) of the vagus nerve. After vagus nerve stimulation, gastric acid levels, serum gastrin and cGMP were raised and cAMP reduced. After stimulation and inhibition of vagus nerve, gastrin and cAMP were increased, cGMP reduced and gastric acid levels remained unchanged. These findings suggest that the vagus nerve, and more particularly the acetylcholine released from its metaganglionic fibers, stimulate parietal cells provoking acid secretion, and also stimulate G cells with subsequent gastrin secretion through cGMP.

Acetylcholine↗
PubMedDate not supplied

Serum and drainage fluid vascular endothelial growth factor levels in early surgical wounds.

BACKGROUND: Wound healing relies on a coordinated expression and release of growth factors controlling angiogenesis. We measured vascular endothelial growth factor (VEGF) levels in serum and early wound fluid following primary sutured and mesh repair of abdominal hernias. MATERIALS AND METHODS: Thirty-seven patients were studied measuring serum and wound drainage fluid VEGF by enzyme-linked immunosorbent assay preoperatively and on the 1st, 3rd, 5th and 7th postoperative days. RESULTS: Serum and wound fluid VEGF levels increased significantly by the 3rd postoperative day and continued to rise during the conduct of the study with wound fluid concentrations always exceeding serum levels. The kinetics of VEGF increases were similar in both types of hernia repair; however, serum and wound levels rose slightly earlier in the mesh repair group. CONCLUSIONS: Steadily increasing levels of VEGF are detected during the early proliferative phase of wound healing in both serum and wound fluid. It is unknown whether either is predictive for delayed hernia recurrence.

Adult↗
PubMedDate not supplied

Phenytoin-induced lymphocytic chemotaxis, angiogenesis and accelerated healing of decubitus ulcer in a patient with stroke.

We studied the effect of topically applied phenytoin on the healing of a decubitus ulcer in the sacral region of an immobile patient with stroke. Another similar, but smaller, ulcer was treated with conventional treatment only and served as a control. The ulcers were measured once a week and biopsies were taken from the margins before, 1 week and 2 weeks after commencing treatment with phenytoin. Clinically, phenytoin substantially accelerated the rate of healing. Microscopic examination of the biopsies showed increased lymphocytic infiltration of the phenytoin-treated lesion. Anti-CD31 immunohistochemistry revealed dense CD31+ lymphocytic infiltration and increased angiogenesis only in the phenytoin-treated lesion. Our findings suggest that phenytoin enhances wound healing by stimulating lymphocytic chemotaxis and up-regulation of angiogenesis.

Chemotaxis, Leukocyte↗
PubMedDate not supplied

Predictive value of risk factors in patients with obstructive jaundice.

Clinical and laboratory parameters that may affect post-operative mortality and morbidity were studied in 215 patients operated on for obstructive jaundice. The cause of the bile duct obstruction was benign disease in 56.7% of patients and malignant disease in 43.3%. Overall postoperative mortality and morbidity rates were 21.9% and 33.5%, respectively. Eight risk factors were shown to be associated with increased mortality: age > 70 years; malignancy; leucocytosis > 15 000 cells/microl and fever > 38.5 degrees C; haematocrit < or = 30%; creatinine > 1.3 mg/dl; albumin < or = 3 g/dl; bilirubin > 20 mg/dl; and serum alkaline phosphatase > 100 IU/l. The simultaneous presence of less than three risk factors was always associated with post-operative survival, but concomitant existence of seven or more risk factors indicated 100% mortality. Understanding the factors related to post-operative morbidity and mortality in patients with obstructive jaundice will better guide appropriate surgical or non-surgical management and lead to improved survival.

Adult↗
PubMedDate not supplied

Delayed perforation of the large bowel due to thermal injury during laparoscopic cholecystectomy.

We report a case of delayed perforation of the large bowel because of thermal injury during a laparoscopic cholecystectomy. A 78-year-old male with symptomatic cholelithiasis underwent a difficult laparoscopic cholecystectomy because of multiple adhesions resulting from two previous cholecystitis episodes. The patient recovered well after surgery and was discharged on post-operative day 2. On postoperative day 10, the patient returned to the hospital with peritonitis. An exploratory laparotomy revealed perforation of the wall of the hepatic flexure of the large bowel, which was centred in a necrotic area 1 cm in diameter. The perforation was sutured and a temporary ileostomy performed, which was closed at a later date. The patient was doing well at a 10-month follow-up review. A delayed rupture of any part of the bowel after laparoscopic surgery can be potentially fatal if not treated during an emergency exploratory laparotomy, even if the clinical signs are not severe.

Aged↗
PubMedDate not supplied

Primary hydatid disease in femoral muscles.

Usually, intramuscular hydatid cysts are secondary, resulting from the spread cysts from other areas either spontaneously or after operations for hydatidosis in other regions. We present an unusual case of a primary hydatid cyst found in the left thigh of a 35-year-old woman, presenting as an enlarging soft-tissue tumour. Ultrasound, computed tomography and magnetic resonance imaging examinations revealed a multilocular intramuscular cyst in the anterior aspect of her left thigh, and no disease at any other location. We removed the entire cyst surgically, and macroscopic and microscopic histopathological examinations confirmed the diagnosis of muscular hydatidosis. Three years after the operation there had been no recurrence. In regions where hydatidosis is endemic, a tumour in any part of the body should be considered a hydatid cyst until proven otherwise.

Adult↗
PubMedDate not supplied

Renal extramedullary hematopoietic tumor diagnosed by fine needle aspiration: a case report.

UNLABELLED: We report a case of a 58 year-old-male with a history of sickle cell anemia, who presented with a left kidney mass. Guided fine needle aspiration of the mass revealed extramedullary hematopoiesis and enabled avoiding an unnecessary surgical procedure. INTRODUCTION: Extramedullary hematopoiesis (EMH) generally occurs in patients with deficient bone marrow hematopoiesis secondary to either peripheral red cell destruction or marrow replacement. EMH is most commonly seen in the liver and spleen as a diffuse lesion. Rarely EMH presents as a solitary mass, posing a diagnostic dilemma. In asymptomatic patients without obvious evidence of hemato-pathology, the differential diagnosis is even more complex. Despite several reports describing the radiographic findings in EMH, fewer promote the use of fine needle aspiration (FNA) in making this diagnosis.

Anemia, Sickle Cell↗
PubMedDate not supplied

Expression patterns of alpha-, beta- and gamma-catenin in pancreatic cancer: correlation with E-cadherin expression, pathological features and prognosis.

BACKGROUND: The E-cadherin-catenin cell adhesion complex has been implicated in tumour invasion and metastasis. In this study, we evaluated the clinical significance of E-cadherin and catenin expression in pancreatic cancer. MATERIALS AND METHODS: The immunohistochemical expression and cellular co-localization of alpha-, beta- and gamma-catenin were investigated in 43 paraffin-embedded specimens of pancreatic cancer. The relationship between their expression and E-cadherin expression, clinicopathological features and prognosis was evaluated. RESULTS: Abnormal alpha-, beta- and gamma-catenin expression was found in 37%, 44% and 40% of cases, respectively. Both alpha-catenin and gamma-catenin expression correlated with disease stage and with lymph node and distant metastases, whereas aberrant beta-catenin expression only correlated with the presence of lymph node metastases. There was a significant and progressive concordance between E-cadherin and alpha-, beta- and gamma-catenin expression patterns, respectively. The expressions of alpha-, beta- and gamma-catenin also significantly correlated with one another. All three catenins, like E-cadherin, were associated with a poor prognosis, but only E-cadherin and alpha-catenin were independent prognostic factors for cancer-specific survival. CONCLUSION: Changes in catenin expression and pancreatic cancer progression are possibly related events. The expression of E-cadherin and alpha-catenin may add useful new prognostic information.

Cadherins↗
PubMedDate not supplied

Does neoplastic gastrin expression remodel the embryonal pattern of the protein? A study in human pancreas.

BACKGROUND/AIMS: To determine the immunoreactivity of gastrin during the development of the human fetal pancreas and ductal pancreatic adenocarcinoma, given that, gastrin positive cells were demonstrated either into its embryonic anlage or into pancreatic cancer. METHODOLOGY: Tissue sections from 15 pancreatic fetal specimens, and an equal number of ductal adenocarcinoma specimens, were assessed using immunohistochemical methods for gastrin. RESULTS: The density of positive cells in the primitive exocrine ductal walls and outgrowing buds was significantly higher than the relevant density in the neoplastic pancreatic tissue of mixed (ductal endocrine) and pure ductal type (p1=0.017, p2<0.0001, p3<0.0001 and p4=0.019, respectively). The above values were estimated from 20-22 weeks of gestation. There was no significant difference in the density of positive cells in the islet cell epithelium from 25-30 weeks, and the neoplastic tissue of mixed (p5=0.24) and pure ductal type (p6=0.55). CONCLUSIONS: The immunostaining for gastrin identifies a subgroup of pancreatic ductal adenocarcinomas with a neuroendocrine component (initially considered as pure ductal tumors), and mixed ductal-endocrine tumors. This pattern of expression in neoplasms recapitulates the normal pattern during the embryonal development of the organ, and may be important for the development of new therapeutic approaches with eventual clinical utility.

Adenocarcinoma↗
PubMedDate not supplied

Correlation of immunohistochemically detected HER-2/neu (c-erbB-2) with histological stage and perineural invasion in pancreatic cancer.

BACKGROUND/AIMS: HER-2/neu (c-erbB-2) oncoprotein is a transmembrane glycoprotein and may function as a growth factor being involved in the regulation of cell growth and cell transformation. c-erbB-2 was correlated with established outcome factors in pancreatic cancer. METHODOLOGY: We performed an analysis of 100 patients with pancreatic cancer using an immunoperoxidase technique on formalin-fixed, paraffin-embedded tissue samples in order to determine HER-2/neu oncoprotein expression along with stage and perineural involvement. RESULTS: HER-2/neu oncoprotein was expressed in the tumors of 21 patients (21%). CONCLUSIONS: Histologic stage, and perineural invasion did not correlate with HER-2/neu oncoprotein.

Adenocarcinoma↗