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M Pera

Publications and source records attributed to M Pera.

At least 19 recordsLinked to original sources
PubMed1997

Liver transplantation for alcoholic cirrhosis with anti-HCV antibodies.

The results of orthotopic liver transplantation (OLT) in patients with alcoholic liver cirrhosis (ALC) are currently similar to those obtained in patients with other indications. However, the frequent association of ALC with hepatitis C virus (HCV) infection may impair these results. We retrospectively studied the consequences of HCV infection on survival and graft function in 59 patients with ALC undergoing OLT. Patients were classified into two groups depending on their HCV serology before transplantation: group 1 comprised 24 anti-HCV-positive patients, and group 2, 35 anti-HCV-negative patients. Patient and graft survival were similar in both groups. Liver function tests 1 and 4 years after OLT showed AST and ALT values that were significantly higher in group 1 patients and post-transplant histologically proven chronic hepatitis was found in 45% and 61% of these patients at 1 and 4 years, respectively. We conclude that pretransplant HCV infection in patients with ALC does not affect survival after OLT. However, one must bear in mind the high incidence of post-transplant chronic hepatitis secondary to recurrence of HCV infection and be cautious when drawing this conclusion.

Adult↗
PubMed1997

Sleeve recording of upper esophageal sphincter resting pressures during cricopharyngeal myotomy.

OBJECTIVE: The manometric effects of a 6-cm cricopharyngeal myotomy are recorded while the operation is being performed from cervical esophagus to the cricopharyngeus and then to the hypopharynx. SUMMARY BACKGROUND DATA: Cricopharyngeal myotomy is used in the treatment of oropharyngeal dysphagia of different causes. The operation decreases the resting pressure in the upper esophageal sphincter (UES). The components responsible for this decrease have not been clarified. METHODS: Fourteen patients with oropharyngeal dysphagia underwent a sleeve recording of the UES resting pressures under general anesthesia before and after sequential myotomy of the pharyngoesophageal junction. Patients were assessed in the awake state before and after the whole myotomy. RESULTS: Upper esophageal pressures remain unchanged after division of 2 cm of the cervical esophageal muscle. Section of 2 cm of the cricopharyngeal area results in a significant decrease of the sphincter resting pressure (p < 0.01). The division of 2 cm of hypopharyngeal muscle results in a further significant reduction of the resting pressure (p < 0.005). CONCLUSIONS: Extension of the cricopharyngeal myotomy over hypopharyngeal musculature produces a more significant decrease of UES resting pressure.

Aged↗
PubMed1996

Comparative analysis of cell surface antigens expressed by cell lines derived from human germ cell tumours.

The pattern of cell surface antigen expression of a set of cell lines derived from human germ cell tumours and corresponding to various cell phenotypes found within these tumours was studied using immunofluorescence. Twenty-two different antibodies were used. Many of these antibodies have been noted to recognise epitopes that are either preferentially expressed by embryonal carcinoma (EC) cells, or by more differentiated cell types. Using scatter plots and rank correlations, 6 groups of antibodies were distinguished with respect to their staining patterns on the cell lines tested. Several antibodies showed a specific staining pattern in relation to the differentiation state of the cells. Two groups of antibodies included those recognising high m.w. glycoproteins (antibodies TRA-1-60, TRA-1-81, GCTM2, 3-177, K4 and K21) and the ganglioseries glycolipid antigens SSEA-3 and -4 (antibodies MC631 and MC813-70). These antibodies mostly stained EC cells but not other cell types, confirming previously published data. However, one of these groups, comprising antibodies K4 and MC631, was more exclusively associated with the EC cell phenotype than was the other group. Antibodies recognising the liver isozyme of alkaline phosphatase (TRA-2-49 and TRA-2-54) also reacted strongly with most EC cell lines, although they reacted significantly with a number of other cell lines as well, whereas antibodies to the placental isozyme tended to react only weakly with EC cells. The antibodies recognising the ganglioseries glycolipids GD2 and GD3 (VIN2PB22 and VINIS56) preferentially stained cells with neuroectodermal characteristics. Other antibodies showed a heterogeneous staining pattern for the cell lines with different phenotypes. The data obtained from the cell lines were, in general, similar to data obtained from immunohistochemical studies on tissue sections of primary germ cell tumours of the adult testis, including carcinoma in situ.

Adult↗
PubMed1996

[Paraesophageal hernias in elderly patients. An indication for laparoscopic surgery].

Paraesophageal hernias are uncommon conditions which appear mainly in elderly people, frequently associated with sliding hernias or gastric volvulus. Considered a high risk pathology, surgical management is preferred to avoid serious complications. Due to advanced age and operative risks, a laparoscopic approach was performed in the three patients with paraesophageal hernia. In mixed hernias, a Nissen or Toupet fundoplication and closure of the hiatal defect was carried out. In a case with gastric rotation, reduction of the herniated stomach and posterior partial fundoplication with gastropexy was performed. No postoperative complications occurred and recovery was satisfactory. Laparoscopic management seems to be a good choice for elective treatment of paraesophageal hernias in elderly patients.

Aged↗
PubMed1995

Uncut Collis-Nissen gastroplasty: early functional results.

BACKGROUND: This study reviewed the short-term results of the uncut Collis-Nissen gastroplasty. METHODS: From 1990 through 1993, 27 consecutive patients (16 men, 11 women) underwent an uncut Collis-Nissen gastroplasty. Mean age was 59 years (range, 30 to 75 years). Three patients had a previous failed antireflux procedure. Indications for operation were gastroesophageal reflux disease resistant to medical treatment in 18 patients and symptomatic hiatal hernia in 9 patients. Fourteen patients had Barrett's esophagus and 4 had a peptic stricture. Complete esophageal function testing including barium swallow, endoscopy, manometry, and 24-hour pH recording was performed in 26 of 27 patients preoperatively and postoperatively. RESULTS: Five patients (19%) had complications, which included atelectasis in 2, cardiac dysrhythmia in 2, and prolonged ileus in 1. There were no operative deaths. Follow-up was complete in all patients and ranged from 8 to 45 months (mean, 22 months). Subjectively, symptoms of reflux were resolved in all patients. Six patients complain of slow esophageal emptying and 3 have occasional episodes of dysphagia. None required postoperative dilation. Ulcers and erosions healed in all 26 patients who underwent endoscopy but recurred in 2 at 21 and 36 months postoperatively. Mean lower esophageal sphincter gradient increased from 8.3 mm Hg preoperatively to 14.6 mm Hg (p = 0.0001). Total percent of acid exposure decreased from 8.0% preoperatively to 1.7% (p = 0.003). CONCLUSIONS: We conclude that the uncut Collis-Nissen procedure provides acceptable short-term control of gastroesophageal reflux disease.

Adult↗
PubMed1995

Adenocarcinoma of the esophagogastric junction and Barrett's esophagus.

BACKGROUND & AIMS: Barrett's esophagus is associated with adenocarcinoma of the esophagus. The aim of this study was to find the prevalence of Barrett's esophagus in patients with adenocarcinoma of the esophagogastric junction. METHODS: Consecutive, freshly resected surgical esophagogastrectomy specimens were examined, and multiple histological sections were made around the tumor periphery. Barrett's esophagus was defined as specialized columnar epithelium above the esophagogastric junction. Tumors centered < or = 2 cm from the junction were defined as junction cancers. RESULTS: Barrett's esophagus was found in 9 of 9 (100%) esophageal adenocarcinomas compared with 0 of 8 (0%) squamous carcinoma controls (P < 0.001). Ten of 24 (42%) junction adenocarcinomas had a Barrett's esophagus. A Barrett's esophagus was found in 8 of 12 (67%) junction cancers < or = 6 cm in length but only 2 of 12 (17%) larger tumors (P < 0.05). Barrett's esophagus was significantly associated with junction tumors < 6 cm compared with squamous carcinoma controls (P < 0.02). In 5 specimens with junction cancer, the length of Barrett's esophagus was < 3 cm, and in 5 specimens it was > or = 3 cm. Specialized epithelium was often found below the esophagogastric junction in controls. CONCLUSIONS: Adenocarcinomas of the esophagogastric junction are associated with short and long segments of Barrett's esophagus. Larger cancers probably overgrow and conceal the underlying specialized columnar epithelium from which they arise.

Adenocarcinoma↗
PubMed1994

Deficient repair of cisplatin-DNA adducts identified in human testicular teratoma cell lines established from tumours from untreated patients.

Germ cell tumour lines appear generally more sensitive in vitro to cisplatin than other cultured cell lines, reflecting their clinical responsiveness. We proposed (Cancer Res 1988, 48, 3019-3024) that cisplatin hypersensitivity, expressed by a testicular teratoma line (SuSa), might be explained by an inability to repair platinated DNA. We have now quantitated cisplatin cytotoxicity by clonogenic assay, and platinum (Pt)-DNA adduct formation and removal immunochemically in four other testicular teratoma continuous cell lines (GCT46, GCT27 clone 4, H32 and H12.1), all established from tissue from non-drug-treated patients. For 1-h in vitro drug exposures, the cisplatin concentration required to reduce survival by 50% (IC50) ranged from 0.09 to 0.42 micrograms/ml (0.3-1.4 microM). Immediately following a 1-h exposure to 5 mu/ml cisplatin, total cellular platination levels ranged from 4.5 to 36.8 fmol Pt per microgram DNA, with lower platination occurring in the most sensitive lines. Following an 18-h post-treatment incubation period, the levels of the major cis-Pt-(NH3)2d(pGpG) (Pt-GG) adducts were not significantly reduced in any of the four lines, indicating a general deficiency in either the rate or extent of removal of these lesions. Deficient removal of the cis-Pt-(NH3)2d(pApG) adducts was also noted in two of the lines. DNA polymerase beta gene expression was comparable in all the tested testicular lines established from previously untreated patients, but markedly lower than that identified in the 833K testicular line, established from a drug-treated patient and identified earlier as proficient in Pt-GG adduct removal (Cancer Res 1988, 48, 3019-3024). Expression of the DNA excision repair genes ERCC-1 and XPBC/ERCC-3 was not significantly different in any of the five lines tested, including the 833K cell line. These data provide evidence of the apparent inability of testicular cell lines, derived from untreated tumours, to repair the major platinum-DNA intrastrand crosslinks, and so provide a biological basis for their hypersensitivity to cisplatin.

Cell Survival↗
PubMed1994

Spectrum of glandular differentiation in experimental carcinoma of the esophagus induced by 2,6-dimethylnitrosomorpholine under the influence of esophagojejunostomy.

To investigate the influence of reflux esophagitis (RE) on the glandular differentiation of carcinomas of the esophagus induced by 2,6-dimethylnitrosomorpholine (2,6-DMNM), a study was carried out using 4 experimental groups and 2 control groups of 8-week-old Sprague-Dawley rats, each consisting of 20 males and 20 females. An esophagojejunostomy (EJ) with gastric preservation was performed in two groups of animals. Fifteen days thereafter the potent esophagotropic carcinogen 2,6-DMNM was subcutaneously injected, once a week for life, at doses of 1/100 and 1/10 of the 50% lethal dose in each group respectively. The result was a spectrum of carcinomatous tumors mainly developing in the lower half of the esophagus, which were thoroughly investigated by serial sectioning, staining for mucins, and in selected cases by electron microscopy. They were classified as follows: 16 pure squamous cell carcinomas (SCC), 5 SCC with focal mucous or glandular differentiation (FGD), 11 pure adenocarcinomas (ADC), and 12 ADC with areas of squamous cell differentiation (SCD). By contrast, in 2 similar experimental groups in which the previous EJ was not performed, 15 animals showed SCC of the pure type, without evidence of mucous or glandular differentiation. No tumors were observed in the two control groups without carcinogen treatment. Of these, the group that underwent EJ showed reflux esophagitis. In conclusion, the tumors of the esophagus induced by 2,6 DMNM under the influence of EJ are not only pure ADC and pure SCC, as we have previously reported, but also intermediate tumors showing either SCC with focal mucous or glandular differentiation (SCC + FGD) or ADC with areas of squamous cell differentiation (ADC + SCD).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1994

Barrett's esophagus.

The development of the columnar-lined lower esophagus, or Barrett's disease, is an acquired condition due to reflux of gastric and duodenal contents. The medical treatment of patients with reflux disease and Barrett's esophagus is currently the same as for patients with reflux without Barrett's disease which may indicate more aggressive antireflux control. Constant surveillance of the Barrett's mucosa remains important. The progression of squamous epithelium to Barrett's metaplasia and eventually invasive carcinoma in a subgroup of patients is well described and becoming more frequent. The discovery of this carcinogenic process is becoming extremely important as it may help improve the dismal long-term prognosis of patients with adenocarcinoma of the distal esophagus and gastroesophageal junction.

Barrett Esophagus↗
PubMed1994

[Cardiac surgery in patients over 70. Its incidence and trends in Spain].

INTRODUCTION AND OBJECTIVES: During the last years elderly population has been growing in all the occidental world. Consequently the number of elderly patients undergoing cardiac surgery has increased. The aim of this work is to know whether this increase has also taken place in Spain. METHODS: A survey among the different Units in the country was performed. The number and percentages of patients older than 70 years with coronary and valvular heart disease operated among 1991 and 1992 was analysed. Twenty-one of the 28 units replied (74%). RESULTS: The percentage of coronary patients older than 70 years operated in 1991 was 15.61% and 19.20% in 1992, a statistically significant increase of 21.84% (p < 0.001). However, there was no significant increase in the number of elderly patients undergoing valvular surgery. CONCLUSIONS: The influence of the elderly population on the activity in cardiac surgery is known to be significant; thus, a careful analysis of the health, social and economic implications seems to be mandatory.

Aged↗
PubMed1994

[Intraportal air secondary to gastric dilatation. A clinical case].

The authors report a case of hepatic portal venous gas (HPVG) secondary to massive gastric dilatation in a diabetic patient following blunt trauma. Both flat plate of the abdomen and ultrasound of the liver were necessary to reach the correct diagnosis. They review the pertinent literature and stress the importance of an accurate nosologic assessment of this uncommon entity in order to avoid undue mishaps.

Abdomen, Acute↗
PubMed1993

Influence of pancreatic and biliary reflux on the development of esophageal carcinoma.

We previously presented an experimental model of Barrett's adenocarcinoma of the esophagus by demonstrating that esophagojejunostomy combined with subcutaneous injection of 2,6-dimethylnitrosomorpholine in Sprague-Dawley rats resulted in development of adenocarcinoma in the distal esophagus. The present study was devised to investigate the influence of pancreatic and biliary duodenal-content reflux on the induction of esophageal carcinoma. Three groups of 8-week-old Sprague-Dawley rats were controls: the first was exposed to pancreatic reflux, the second to biliary reflux, and the third to both. The other three experimental groups were similar except that a 1/100 LD50 dose of 2,6-dimethylnitrosomorpholine was injected subcutaneously weekly, starting on day 15. Carcinoma of the esophagus was induced only in animals receiving the carcinogen after exposure to either pancreatic reflux (3/22, 13%) or pancreatic and biliary reflux (9/27, 33%). Half of the carcinomas were adenocarcinoma and half were squamous cell carcinoma. These findings suggest that under these experimental conditions, in which the carcinogen is used in a low dose, esophageal carcinoma is induced only when pancreatic secretions are present in the duodenal-content reflux. Biliary reflux, however, appears to exert a cocarcinogenic effect when combined with pancreatic secretions. The clinical relevance of these findings needs further evaluation. Conceivably, the elimination of pancreatic and biliary duodenal-content reflux in patients with documented Barrett's mucosa may inhibit the progression from metaplasia to adenocarcinoma.

Adenocarcinoma↗
PubMed1993

Barrett's disease: pathophysiology of metaplasia and adenocarcinoma.

Peptic ulceration arising in the lower esophagus lined by columnar epithelium was described in detail by Tileston in 1906. Although this concept was challenged in 1950 by Barrett, experimental and clinical evidence has now conclusively demonstrated that Barrett's metaplasia is an acquired condition and is a consequence of chronic reflux of gastric or duodenal contents or both. Current concepts suggest that unknown trophic factors present in these secretions stimulate proliferation of multipotential reserve cells located in the esophageal submucosal glands resulting in columnar metaplasia of the normal squamous epithelium with subsequent potential for malignant degeneration. Today, numerous patients are affected by reflux esophagitis, a lesser number by Barrett's metaplasia, and a smaller but ever-enlarging group by adenocarcinoma. Although high-grade dysplasia is considered a precursor to invasive adenocarcinoma, detection of this abnormal mucosa remains controversial and currently requires esophagoscopy with biopsy. Epithelial markers, such as increased activity of mucosal ornithine decarboxylase, sulfomucin production, nuclear DNA aneuploidy, and recently molecular analysis, have also been proposed to identify those paitents at increased risk for malignant degeneration. As more is learned about the pathogenesis of Barrett's disease, perhaps these cancers can ultimately be prevented.

Adenocarcinoma↗
PubMed1993

Increasing incidence of adenocarcinoma of the esophagus and esophagogastric junction.

BACKGROUND: The aim of this study was to determine whether the incidence of adenocarcinoma of the esophagus and esophagogastric junction in a well-defined population was higher than previously recognized. METHODS: Clinical records and original histological slides from patients residing in Olmsted County, Minnesota, were reviewed and compared with a previous study in the same population. RESULTS: The incidence of esophageal adenocarcinoma rose from 0.13 for 1935-1971 to 0.74 for 1974-1989, and the incidence of adenocarcinoma of the esophagogastric junction rose from 0.25 to 1.34 per 100,000 person-years. Histological review of preserved surgical specimens showed associated intestinal metaplasia (Barrett's esophagus) in 2 of 2 esophageal and in 5 of 9 esophagogastric adenocarcinomas. CONCLUSIONS: The incidence of adenocarcinoma in each location increased five to sixfold compared with the earlier study. This increase could not be explained by improved diagnostic methods or classification changes. The association with Barrett's esophagus and the parallel increased incidence of cancer in each location is evidence that adenocarcinoma of the esophagus and of the esophagogastric junction are related disorders.

Adenocarcinoma↗
PubMed1992

[A case of retroperitoneal leiomyosarcoma. Considerations].

A case of retroperitoneal leiomyosarcoma is reported. The retroperitoneal localization is quite unusual and early diagnosis is really difficult. Only operation can offer any chance for cure of this neoplasm and radiotherapy and chemotherapy can be very useful. Tumor size and location are the major prognostic factors.

Female↗
PubMed1992

Barrett's esophagus with high-grade dysplasia: an indication for esophagectomy?

Between 1982 and 1991, 19 patients (17 men and 2 women) with Barrett's esophagus, 10 of whom were in a surveillance program, were found to have high-grade dysplasia without evidence of invasive carcinoma. Median age was 66 years (range, 30 to 79 years). Heartburn was the most common presenting symptom. Esophagoscopy at the time of high-grade dysplasia diagnosis demonstrated normal Barrett's mucosa in 10 patients (53%), shallow ulcers in 3, slight mucosal irregularities in 2, small mucosal nodules in 2, stricture in 1, and shallow ulcer with stricture in 1. Eighteen patients underwent esophagectomy. There were no operative deaths. Nine patients (50%) had invasive carcinoma. Postsurgical stage was stage 0 in 9 patients, stage I in 6, stage IIA in 2, and stage IIB in 1. Median follow-up was 34 months (range, 2 to 116 months). Recurrent cancer developed in 2 patients. Overall 5-year survival was 66.7%; 5-year survival for patients with stage 0 disease was 100% and for stage I and II disease, 35.7%. We conclude that high-grade dysplasia in an indication for esophageal resection because of the high rate of associated early invasive carcinoma and that resection can be done safely with the expectation of excellent long-term survival. Because of these findings, we continue to recommend endoscopic surveillance in all patients with Barrett's esophagus.

Adenocarcinoma↗