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Biomedical subjects

C Simopoulos

Publications and source records attributed to C Simopoulos.

At least 19 recordsLinked to original sources

Pre- and postsurgical biomagnetic activity in malt-type gastric lesions. A case report.

PURPOSE: To evaluate the biomagnetic activity of a low-grade mucosa-associated lymphoid tissue (MALT-) type gastric lymphoma, and to determine if this procedure could be an adjunct to endoscopic ultrasonography (EUS) in the assessment of the disease pre- and postsurgically. MATERIAL AND METHODS: A 47-year-old female with a 2-year clinical history of a low-grade MALT-type gastric lymphoma associated with Helicobacter pylori was examined. The disease showed no histologic remission after eradication of the H. pylori infection and subsequent treatment with chemotherapy and the patient was classified as stage II EA. A decision for surgical resection was made. Biomagnetic waveform recordings were made in the target area before and after surgery and the Fourier analysis of these recordings was performed. RESULTS: The gastric lymphoma biomagnetic waveforms showed high amplitudes (1.8 pT) before and low amplitudes (0.6 pT) after resection. The corresponding Fourier analysis demonstrated that the maximum spectral power of the presurgical measurement was elevated (mean 235 +/- 847 pT2/Hz) compared with that obtained postsurgically (mean 725 +/- 89 pT2/Hz). The difference was of statistical significance ( p < 0.0001, t-test). CONCLUSION: Biomagnetic monitoring of gastric lymphoma, which is an entirely new diagnostic modality, could be a supplement to EUS for assessing remission or persistence of disease with medical treatment during follow up.

Female↗

Hypoxia inducible factor 1alpha and 2alpha overexpression in inflammatory bowel disease.

AIMS: Hypoxia inducible factors 1alpha and 2alpha (HIF1alpha and HIF2alpha) are hypoxia regulated transcriptional factors, which control the expression of a variety of genes responsible for angiogenesis, glycolysis, and the inhibition of apoptosis. Because angiogenesis and tissue regeneration are integral components of the inflammatory process, this study was designed to investigate the role of HIFalpha molecules in inflammatory bowel disease. METHODS: Surgical specimens from patients with active ulcerative colitis (UC) and Crohn's disease (CD) were assessed immunohistochemically for HIF1alpha and HIF2alpha reactivity, and the expression of these molecules was compared with the expression of the angiogenic factors thymidine phosphorylase (TP), vascular endothelial growth factor (VEGF), and VEGF-KDR activated vasculature. The vascular density of the lesions was also assessed using anti-CD31 immunostaining. RESULTS: HIF1alpha was expressed focally (epithelial cells, stromal fibroblasts, and myocytes) in both UC and CD, whereas HIF2alpha was expressed focally in UC and diffusely in CD. TP expression was uniformly positive in both diseases. VEGF expression was absent in CD, and weakly positive in UC. The VEGF-KDR reactivity of the submucosal vasculature was only slightly increased in UC and CD compared with normal tissue. The inflammatory cells stained with HIF2alpha and TP in all cases, but the reactivity was generalised in CD and focal in UC. In both diseases, vascular density was significantly higher than that seen in normal tissue. CONCLUSIONS: The discordant expression of HIF2alpha and VEGF in CD suggests an inherent deficiency of the intestine to respond to various stresses by the induction of VEGF. This finding should be investigated further.

Adult↗

Nucleolar organizer regions (NORs). Their significance in the determination of the origin of the lymphoid vessels.

AIM: The aim of this study is the evaluation of the cellular activity of the embryonal mesenchyme in order to investigate if the primitive lymph vessels are derived from clefts of the mesenchyme or from capillary offshoots from the endothelium of the veins. For this reason we applied the quantitative estimation of nucleolar organizer regions (NORs) in the endothelial cells of the lymph and blood vessels, as well as in the mesenchymal cells that surround these vessels. METHODS: Our material consisted of the histological sections from the proper mesenterium of 30 embryos in different stages of development (10th, 12th, 15th, 20th, 23th and 30th week). RESULTS: A statistically significant difference in the average AgNORs value in the endothelial (ANOVA, p<0.0001) and the mesenchymal cells (ANOVA, p<0.0001) between lymph vessels, blood vessels at close and blood vessels at distant regions (10th, 12th, 15th week) was found. There was no statistically significant difference of the average AgNORs value in the endothelial (ANOVA, p=0.55) and the mesenchymal cells (ANOVA, p=0.49) between lymph vessels, blood vessels at close and blood vessels at distant regions (20th, 23th, 30th week). CONCLUSION: The above results suggest that the development of the lymph vessels follows that of the blood vessels. Furthermore, the intense protein synthesis that is expressed by means of NORs in the mesenchymal cells surrounding lymph vessels from the 10th to the 15th week of development is an additional proof of the view that the primitive lymph vessels are derived from clefts into the embryonal mesenchyma and not from capillary offshoots of the endothelium of the blood vessels.

Gestational Age↗

Detection of chromosome 1p deletion using FISH on meningioma touch imprints suggest a region outside chromosome 22 as important in tumor recurrence.

BACKGROUND: Atypical and anaplastic meningiomas tend to recur and to invade adjacent brain, bone, and skin. They can also metastasize to extracranial organs such as the lung, liver, or bone causing death. The classic genetic abnormality is loss in chromosome 22. Recent reports have indicated that allelic deletion of chromosome 1p is associated with malignant progression of meningiomas. METHODS: Cytogenetic analysis of 4 meningiomas was performed using double target fluorescent in situ hybridization and focusing on chromosomes 1 and 22. The meningioma series included 4 patients whose tumors were histologically benign. RESULTS: One patient's tumor had recurred. FISH was performed on 500 nuclei/tumors. All our cases showed a loss of chromosome 22q while only 1 meningioma showed an additional loss of chromosome 1p, and this was the recurred one. CONCLUSIONS: The results of this study support the existence of tumor suppressor gene(s) on 1p associated with recurrence in meningiomas and suggest that status of chromosome 1p by FISH may assist physicians in predicting prognosis of patients affected by this tumor. However more in-vestigation is needed in this direction, as our re-sults refer to a small number of subjects studied.

Adult↗

Spontaneous pneumomediastinum: is a chest X-ray sufficient?

Spontaneous pneumomediastinum (SPM) is an uncommon disease defined as a non-traumatic presence of free air in the mediastinum, without underlying disease. We present a 13-year- old boy who was previously in a perfect health, who was presented with subcutaneous cervical emphysema, dysphagia, chest and neck pain. The chest roentgenogram revealed the presence of subcutaneous emphysema without any other abnormal findings. A computer tomography (CT) scan was obtained, and this confirmed the existence of subcutaneous cervical emphysema and also the presence of pneumomediastinum. The child's progress was uneventful and after 6 days he was discharged from the hospital in excellent clinical condition. We propose that chest CT is useful, in less obvious cases of SPM, to detect the free air in the mediastinum and probably SPM is underdiagnosed in clinical practice in the young people.

Adolescent↗

Laparoscopic cholecystectomy in a patient with previous open cholecystostomy.

We report the case of a successful elective interval laparoscopic cholecystectomy in a patient with a previous tube cholecystostomy that had been performed surgically 8 weeks earlier for an attack of acute calculous cholecystitis. At surgery, the major omentum was adherent to the right lateral abdominal wall, completely covering the liver edge, the gallbladder, and the inserted tube. The gallbladder and the tube within it were dissected free from the abdominal wall and the greater omentum, the cholecystostomy tube was removed, and the operation was completed successfully without any further difficulties.

Aged↗

An unusual cause of delayed presentation of laparoscopic common bile duct injury.

We describe an unusual case of a laparoscopic common bile duct (CBD) injury that presented with cholangitis 2 years after an apparently uneventful laparoscopic cholecystectomy. Preoperative ultrasound and endoscopic retrograde cholangiography suggested choledocholithiasis, showing proximal and intrahepatic duct dilatation with an inability to relieve the obstruction. At surgery, a lateral injury of the CBD wall with partial wall loss was found, adherent to an amorphous pigmented mass with the appearance of a knitted fabric causing CBD obstruction. The CBD was successfully reconstructed with a Roux-en-Y end-to-side hepaticojejunostomy, where the end of the Roux loop was anastomosed to the lateral CBD defect.

Aged↗

Serum E-cadherin concentrations and their response during laparoscopic and open cholecystectomy.

BACKGROUND: Elevated serum levels of the cell adhesion molecule E-cadherin have been associated with the presence of tissue injury and inflammation. We compared soluble E-cadherin response during laparoscopic and open cholecystectomy. METHODS: The E-cadherin response to surgery was studied in 16 patients undergoing laparoscopic cholecystectomy and 12 patients undergoing open cholecystectomy. Serum E-cadherin levels were measured by an enzyme immunoassay (ELISA) preoperatively, 10 and 30 min after the commencement of surgery, and at 6 and 24 h following the operation. RESULTS: Serum E-cadherin levels decreased progressively during laparoscopic cholecystectomy; their concentrations at 24 h after surgery were significantly lower when compared with preoperative values. In the open cholecystectomy group, serum E-cadherin levels did not differ from preoperative values at any time point. Serum E-cadherin concentrations at 24 h after surgery and the cumulative E-cadherin response were significantly higher in the open cholecystectomy group than in the laparoscopic group. CONCLUSION: Compared with open cholecystectomy, the cumulative E-cadherin response is significantly reduced following laparoscopic cholecystectomy.

Cadherins↗

Laparoscopic cholecystectomy in a patient with situs inversus totalis and previous abdominal surgery.

Situs inversus totalis is a rare congenital defect that can present difficulties during laparoscopic surgery due to the mirror-image anatomy. We report a patient with symptomatic cholelithiasis and previous abdominal surgery in whom a chest X-ray revealed a right-sided heart, whereas abdominal ultrasound revealed that his gallbladder was located in the left hypochondrium. At surgery, the surgeon and the camera assistant were standing on the right-hand side of the patient, and the first assistant was standing on the left. The camera was introduced through an umbilical incision, and laparoscopy confirmed the situs inversus. The other 10-mm trocar was placed in the midline left of the falciform ligament and two 5-mm trocars were placed in the left subcostal midclavicular line and anterior axillary line, respectively. After dissection of multiple adhesions caused by previous abdominal surgery, a standard laparoscopic cholecystectomy was performed successfully. This report suggests that situs inversus is not a contraindication for laparoscopic surgery. However, the procedure is more difficult and potentially hazardous due to the mirror-image anatomy (particularly the transposition of biliary ducts) causing difficulties in orientation, so that extreme care is required to avoid iatrogenic injuries. Despite these factors, laparoscopic cholecystectomy can be performed safely in patients with situs inversus totalis.

Abdomen↗

Spontaneous pneumothorax resulting from congenital cystic adenomatoid malformation in a pre-term infant: case report and literature review.

In the literature there are only three reported cases of spontaneous pneumothorax resulting from congenital cystic adenomatoid malformation in children under 1 year and for whom any resuscitative efforts were made. We present here a fourth case of a pre-term baby girl who was in perfect health, until she suffered a spontaneous pneumothorax as the initial manifestation of congenital cystic adenomatoid malformation of the lung at 10 weeks of age. Atypical segmentectomy with the use of stapling devices was successful. The characteristics of this particular manifestation are discussed.

Cystic Adenomatoid Malformation of Lung, Congenita↗

Prognostic role of angiogenesis in operable carcinoma of the gallbladder.

The prognostic significance of intratumoral angiogenesis was investigated in 62 patients with stage I-III carcinomas of the gallbladder treated with simple cholecystectomy. Microvessel density (MVD) was assessed immunohistochemically, using the alkaline phosphatase/anti-alkaline phosphatase method and the monoclonal antibody CD31. The mean MVD was 30.5 vessels per x 200 optical field. Using the thirty-third and the sixty-sixth percentile, the patients were grouped into three MVD categories: low (MVD 9-18; 20 patients), medium (MVD 19-31; 20 patients), and high (MVD 32-86; 22 patients). A high MVD was more frequent in well-differentiated adenocarcinomas compared with moderately and poorly differentiated tumors (p = 0.04), but there was no statistically significant association between MVD and T stage, or patients' age or sex. Multivariate analysis, including MVD, T stage, and histologic grade, showed that MVD was a significant independent prognostic factor in carcinomas of the gallbladder (p = 0.001, t ratio 3.3). It is believed that the assessment of intratumoral angiogenesis in patients with operable gallbladder carcinomas may be useful in predicting prognosis and, perhaps, in decision making for postoperative adjuvant treatment.

Adult↗

Blockade of branches of the ophthalmic nerve in the management of acute attack of migraine.

The aim of this study was the evaluation of the blockade of branches of ophthalmic nerve in the management of the acute attack of migraine headache localized to the ocular region. The study included 70 female patients 23-60 years old who presented to the pain clinic at our hospital with an acute attack of migraine headache localized to the ocular and retro-ocular region. A targeted history and a neurologic examination were performed in all patients to confirm the diagnosis and at the same time to rule out life-threatening neurological dysfunction. The method applied was the blockade of the supraorbital and supratrochlear nerves which are branches of the ophthalmic nerve. By the use of a fine short needle 27G the nerves were sought for until paraesthesia is obtained and then 1 ml of lignocaine 2% with adrenaline 1:200,000 was injected in every one of the three sites of the nerves. The migraine acute attack was relieved in 58/70 patients (82%), while in 12/70 patients (18%) the results were poor. The pain relief started 3-4 min after the injection and was completed in 10-15 min. Our results support that the blockade of the branches of the ophthalmic nerve seems to be a safe and effective technique in the management of the acute attack of migraine localized to the ocular and retro-ocular region.

Acute Disease↗

A quantitative study of collagen production by human smooth muscle cells during intestinal morphogenesis.

Differentiating mesenchymal cells and the extracellular matrix that these cells produce constitute the structural basis for developing organs. The splanchnopleuric mesenchyme surrounding the developing gut and respiratory tubes provides connective tissue cells to the lamina propria/submucosa and smooth muscle cells to the muscularis musosae/muscularis externa. In human fetal intestine, the identity of the matrix-producing cell or cells has begun to be elucidated. The smooth muscle cell is one of the sources of collagen fibers in the extracellular matrix in the developing human fetal intestine and collagen production is a significant function of smooth muscle cells during intestinal organogenesis. The aim of the current study was the quantitative investigation of collagen production by human fetal intestinal smooth muscle cells in various stages of development (10 to 23 weeks of gestational age). Identification of the mesenchymal cells/extracellular matrix was confirmed by immunohistochemical techniques using the following monoclonal antibodies: actin, desmin, vimentin, collagen IV and fibronectin. Histochemical stains for the presence of extracellular matrix components were also performed. Immunohistochemical analysis and the results of the histochemistry of the fetal human intestine in various stages of development revealed that the muscle cells of the muscularis externa contribute to the production of collagen in collaboration with the mesenchymal cells. This is more evident between 10 to 14 weeks of gestational age.

Actins↗

Large granular lymphocytes (LGLS) activity in women with spontaneous abortions during the 1st trimester of gestation.

BACKGROUND: Despite increasing knowledge about the cell subsets that exist in the decidua in normal early pregnancy, little is known about the decidual cell subsets in women with spontaneous pregnancy failure. Decidual large granular lymphocytes (LGLs) are the most abundant lymphoid cell type found in 1st trimester maternal decidua. The function of LGLs remains controversial although freshly isolated LGLs have been shown to exert a weak natural killer cell (NK) activity. METHODS: Decidual leukocytes were investigated in 15 cases of spontaneous abortion and 15 cases of voluntary miscarriage, at 8th, 10th and 12th gestational week using a panel of monoclonal antibodies against Granzyme B (GRAN-B), CD2, CD38, CD56, and CD57 antigens and the immunoperoxidase technique. LGLs were demonstrated with the phloxine-tartazine stain. RESULTS: There was a statistically significant increase in the number of CD56 and CD57 positive cells (33.3%) to the advantage of spontaneous abortions (p<0.0001). No statistically significant difference was found in the number of GRAN-B, CD2 and CD38 positive cells in normal early pregnancy and in spontaneous abortion (overall gestational age p=0.22, 8th gestational week p=0.18, 10th and 12th gestational week, p=0.091). CONCLUSIONS: Our findings confirm previous studies referring that LGLs may have a cytotoxic activity similar to the NK activity and suggest an adverse pregnancy outcome.

Abortion, Spontaneous↗

Immunophenotypic profile of tumor infiltrating lymphocytes in medullary carcinoma of the breast.

Medullary carcinoma (MC) of the breast is considered to carry a more favorable prognosis than other subtypes of infiltrating ductal carcinoma. This is a biological paradox because its clinical behavior contrasts with its anaplastic morphology. MC is characterized by a dense lymphocytic infiltrate. In this study, we determined the immunological profile of tumor infiltrating lymphocytes (TILs) in MC by CD20 (L26), CD8, and CD45RO (UCHL 1) immunostaining on paraffin-embedded sections. We examined 14 cases of typical MC (TMC), 15 cases of atypical MC (AMC) classified according to Ridolfi criteria (1977) and 19 cases of poorly differentiated infiltrating ductal carcinoma (PDC-NOS). TILs were quantified separately into cells infiltrating tumor nests (intraepithelial) and cells infiltrating tumor stroma (stromal). The number of CD8 positive and CD20 positive cells infiltrating tumor nests and tumor stroma were significantly increased in TMC and AMC as opposed to the PDC-NOS group. There was a loss in the number of CD45RO positive cells, both intraepithelial and stromal, in TMC and AMC as opposed to the PDC-NOS group. We conclude that MC tumor lymphocytic infiltrate demonstrates a mixed-T cytotoxic (CD8+) and B cell (CD20+)-immunophenotypic profile. This might in part explain the improved clinical outcome of the disease.

Antigens, CD20↗

Immunohistochemical expression of alpha-smooth muscle actin in infiltrating ductal carcinoma of the breast with productive fibrosis.

Myoepithelial cells are normally located between the epithelial cells and the basal lamina of secretory elements of exocrine glands. Their role in the histogenesis of breast tumours has been studied extensively, and a definite differentiation towards myoepithelial cells has been demonstrated in adenoid cystic carcinoma, adenomyoepithelioma, low-grade adenosquamous (syringomatous) carcinoma, pure malignant myoepithelioma and poorly differentiated myoepithelial-rich breast carcinoma. All these tumours are of low malignancy, with the exception of malignant myoepithelioma and poorly differentiated myoepithelial-rich carcinoma. We examined the possibility that invasive ductal carcinoma of the breast might show differentiation towards both epithelial and myoepithelial cells because there is no reason to assume that one type of differentiation necessarily excludes the other. We performed the avidin-biotin immunohistochemical analysis of 20 cases of infiltrating ductal carcinomas (IDCs) with diffuse fibrosis, 20 cases of IDCs without fibrosis and five cases of metaplastic carcinomas, to detect myoepithelial differentiation of the tumour cells. Myoepithelial differentiation was determined by the expression of alpha-smooth muscle actin (alpha-SMA). We concluded that IDCs with diffuse fibrosis are associated with a myoepithelial immunophenotype of carcinoma cells.

Actins↗

Expression of fibrillar proteins and vimentin in developing chorionic villi is related to fetal maturation.

Using an immunocytochemical technique, the extracellular matrix components fibronectin, vimentin, laminin and collagen type IV were investigated in human chorionic villi of various stages of development. Fibronectin and laminin were consistently positive throughout embryonic development. Vimentin and collagen type IV were negative in first and second trimester chorionic villi, but became positive in term placentas. With the exception of laminin, all extracellular matrix molecules were detected in the villous stroma and, with the exception of vimentin, they were localized in the basement membranes. Our data suggest that fibronectin and laminin are essential components of the villous structure, while the presence of vimentin and collagen type IV in the chorionic villi should be regarded as an indicator of fetal maturation.

Chorionic Villi↗