PubMed Health⌕ Search

Biomedical subjects

J R Izbicki

Publications and source records attributed to J R Izbicki.

At least 19 recordsLinked to original sources

Ambulatory long-term pH monitoring in pigs.

BACKGROUND: pH monitoring has been established as the "gold standard" in the diagnosis of gastroesophageal reflux. Evaluation of experimental antireflux therapy should therefore also include this technique, but a suitable technique in an experimental model did not exist so far. The aim of our study was to establish a reliable method for the evaluation of an experimental reflux model in pigs. METHODS: A total of 33 German Landrace pigs with an average body weight of 56 (50.2-67.2) kg were included. pH monitoring was performed before and after open cardiomyotomy in each animal. All manipulations were performed under general anesthesia. After manometric localization of the gastroesophageal high-pressure zone, a standard pH probe was inserted into the pharynx through a small needle-punctured canal on the side of the animal's snout and placed under endoscopic guidance with the proximal sensor 3 cm above the lower esophageal sphincter (LES) and the distal sensor in the stomach for reference. The harness to carry the pH recorder on the animal's back consisted of a modified belly strap that enabled the animal to move around without limitation. For analysis the same threshold levels were defined as in humans. Gastroesophageal reflux was induced by cardiomyotomy. RESULTS: The placement of the standard pH probe was possible in all cases. Inserting the probe on the side of the snout left the animals free to nuzzle, which complies with the normal habits of pigs, without breaking the probes and without being compromised in their natural behavior. Repeated punctures for multiple measurements were easily feasible. We performed up to three examinations in each individual animal. Recording was performed for 48 h. A mean number of 67.3 (+/-9.7) acidic refluxes were registered. The mean number of long acidic refluxes was 3.2 (+/-0.75). For an average total time of 75.5 (+/-14.3) min the pH was below 4 accounting for a fraction time pH below 4 of 3.5% (+/-0.68%). Following cardiomyotomy the number of acidic refluxes increased significantly to 166.1 (+/-21.8) and the number of long refluxes to 17.74 (+/-3.35). The total time of pH below 4 increased to 371.3 (+/-62) min so that the fraction time pH below 4 was 14.5% ( p = 0.0006). CONCLUSION: pH monitoring should be mandatory in any investigation of antireflux therapy. Our method is easy and secure to perform. It is suitable for other gastrointestinal investigations (Bilitec, long-term manometry) that could be carried out using the same technique. The described data represent the basis for other investigations of experimental antireflux therapy.

Animals↗

[Prognostic relevance of biological and molecular markers in oncology. Criteria for planning and interpreting studies].

Experts on different specialties (surgery, pathology, molecular biology and medical statistics) discussed the evaluation of prognostic factors during a workshop. The most important results presented are: (1) the prognostic relevance of new biological or molecular markers must be evaluated in a phase-III prognostic study. To establish such a marker in the UICC-TNM-classification in at least two different centers, two multivariate analyses according to defined criteria are necessary; (2) the standards of laboratory methods have to be defined, e.g.,which method to apply for RNA-analysis,which materials to used, etc; (3) intensive data analysis should be done before using methods of multivariate analysis. The criteria for the presentation of survival curves are given in detail; (4) in multivariate analysis, the Cox proportional hazard regression for survival outcomes is discussed with explanations and examples of the terms relative risk, odds-ratio, hazard and relative hazard. The arrangement and interpretation of a good prognostic study should be performed as an interdisciplinary approach.

Biomarkers, Tumor↗

[Partial ischemia. Occlusive and nonocclusive mesenteric ischemia, ischemic colitis, systemic lupus erythematosus].

Partial mesenteric ischemia is defined as an incomplete occlusion of the superior mesenteric artery resulting in acute abdominal pain, distended abdomen,and bowel hypomotility on auscultation. This disease can be acute or chronic and is caused by vascular occlusion or non-occlusive mechanisms. CT scan and ultrasound show a thickening of the ischemic bowel wall. On endoscopy, initially mucosal edema is observed which may proceed to necrosis. Therapy modalities depend upon the clinical findings: prevailing acute abdominal pain and peritonitis result in emergency laparotomy; prevailing cramping abdominal pain without clinical signs of peritonitis allows time for further diagnostic steps such as mesenteric angiography and interventional procedures. Laparoscopy should be performed in exceptional situations only.

Abdomen, Acute↗

[Recurrent intestinal bleeding in a patient with arterio-venous fistulas in the small bowel, limited mesenteric varicosis without portal hypertension and malrotation type I].

A case of vascular malformations of the small intestine associated with malrotation Type I of the right colon is reported. Representing rare conditions, vascular malformations in the small bowel are not accessible endoscopically. Therefore, gastrointestinal haemorrhage originating from this "terra incognita" is difficult to diagnose. Our patient had a medical history of anaemia of 17 years before admitted to our hospital. After a preoperative blood pool scan had evidenced the bleeding source in the proximal jejunum, the patient underwent explorative laparotomy. The bleeding source was identified and resection of a jejunal segment was performed. Intraoperatively, malrotation type I was found. Histological examination revealed angiodysplasia extending full thickness of the intestinal wall with predominance in the submucosa and serosa. Secondary arterialisation was seen in the vessels of the serosa resembling varicosis-like lesions at gross inspection. The patient did not suffer from portal hypertension. Postoperative course was uneventful and no further bleeding occurred.

Adult↗

Expression of HER2/neu does not correlate with survival in soft tissue sarcoma.

BACKGROUND: The expression of HER2/neu has been identified as a prognostic factor in several malignant diseases. However, only sparse data exist correlating HER2/neu expression in soft tissue sarcoma with subsequent tumor progression or recurrence. The purpose of this study was to investigate the clinical significance of HER2/neu in adult soft tissue sarcoma (STS). METHODS: Tumor specimens of patients with STS were evaluated regarding HER2/neu expression using immunohistochemistry. The significance of the proposed prognostic indicators was evaluated in relation to survival and local recurrence. RESULTS: Of 62 analyzed specimens, 43 tumors were HER2/neu negative compared to 19 HER2/neu positive tumors. Kaplan-Meier analysis indicated no difference in survival according to HER2/neu expression (p = 0.31, log-rank test = 1.10). Variables that were predictive of longer survival included better resection quality (R0, p < 0.01) and smaller tumor size (T1, p = 0.02). CONCLUSION: HER2/neu expression does not correlate with prognosis of soft tissue sarcomas. Its evaluation for tumor prognosis as well as for the identification for adjuvant therapeutic strategies does not appear warranted at this point.

Adult↗

Chronic pancreatitis: etiology, pathogenesis, diagnosis, and treatment.

BACKGROUND AND AIMS: This review discusses current concepts regarding the etiology, pathogenesis, diagnosis, and treatment of chronic pancreatitis. RESULTS: Treatment of patients suffering from complications of chronic pancreatitis remains a major challenge. Continuous alcohol consumption, a disease with enormous personal and social impact, is still the leading factor in the development of chronic pancreatitis. The most distressing symptom for the patient is pain, which in many instances has already led to a considerable analgesic abuse before a specialist is even consulted. The development of an enlargement of the pancreatic head, the "pacemaker of the disease," parallels pain and potential organ complications such as common bile duct stenosis or portal hypertension. What triggers pancreatic head enlargement is still not known; in particular it is unclear what triggers growth factors to step into action. Pain is most likely due to a combination of hypertension in the organ and parenchymal alterations. Current therapeutic concepts therefore aim at alleviating pain and at management of organ complications while preserving functional tissue to best prevent exocrine and endocrine dysfunction. The ideal procedure thus seems today to be the "customized" pancreatic head resection with additional optional drainage of the pancreatic body and tail.

Chronic Disease↗

Intractable hiccup: an odd complication after laparoscopic fundoplication for gastroesophageal reflux disease.

Intractable hiccup can be an unbearable circumstance and its treatment is often frustrating. More than 100 causes for hiccup have been described in the literature; the most common cause is gastroesophageal reflux disease (GERD). We report a case of a 31-year-old patient who suffered from intractable hiccup starting 3 weeks after laparoscopic Nissen fundoplication for GERD, a potential surgical complication that has not been described. After frustrating medical treatment, the patient underwent computed tomography and nerve stimulator-guided blockade of vagal and phrenic nerves on each side separately. Hiccup ceased only after blockade of the right phrenic nerve with 4 ml/h l% ropivacaine and relapsed soon after discontinuation. He underwent thoracoscopic right phrenicectomy, which rendered him symptom free for well over 2 months, at the time of this writing.

Adult↗

["Multimedia symposium wares". An enrichment of medical and graduate education?].

The continual development of the internet has supported the spread of surgical knowledge by electronic means. High quality products have to be offered from a software as well as a contents point of view. The question as to whether these new media and their contents have a real value for efficient and motivating use in medical education needed to be answered by first assessing a quality profile for the development of surgical educational modules which were then evaluated on the basis of so-called "symposia ware". First, the reactions and opinions of physicians at 47 universities were assessed by a standardized questionnaire concerning their demands on multimedia teaching/learning modules. Several different aspects of technique, content, presentation, didactics and background knowledge were analyzed. In a second step, their opinions were evaluated concerning two applications (symposia implemented on CD-ROM as a slideshow with original slides and audio) with surgical and gastroenterological contents by standardized questionnaire. Questions concerning personal background such as educational status and experience with computers, e-mail and the internet on one hand and the CD-ROM itself concerning content, relevance for daily clinical work and continuing medical education as well as the quality of the application on the other hand, were evaluated using marks (1 = best, 6 = worst). A total of 320 physicians participated in the first part of the interview. Of these, 93% were equipped with computers in hospital as well as privately. The Internet was used by 90% of them. The majority declined a full text presentation as well as the application of scroll fields. The participants rather favored the integration of text, pictures, animations and videos. Furthermore, 95% demanded the provision on the internet. Thirty-seven colleagues in their 5th (1-11) year of training were interviewed, and of those, 27 were working in a surgical department and 10 in a medical department. Individual computer knowledge was rated with a median of 3. This revealed that 60% were equipped with computers in hospital as well as at home, the remaining 40% had computers either in hospital or at home. All participants used the internet. In total, 57% had experience with "Symposia ware". The rating of the "Symposia ware" itself was positive. Relevance and applicability of a slideshow for imparting knowledge were rated with a median of 2. This showed that 81% would buy the CD-ROM in principle, and 89% would spent up to 50 EUR. Quality, language, content and user-friendliness were all rated 2. Physicians frequently use computers and the internet. All this indicates a high degree of acceptance of electronic teaching/learning modules in medical education. A uniform structure of contents as well as a platform-independent, web-based presentation is appreciated. To enhance illustration, a picture and video-oriented visualization should be chosen. Overall, "symposia ware" is rated positively. It should cost no more than 50 EUR and it represents a valuable source of information for physicians.

CD-ROM↗

[The Internet as a source for information retrieval. Example: soft tissue sarcoma].

INTRODUCTION: Due to increasing availability, easier access, and rapid growth of information, the Internet has become an important source of medical information. We analyzed the value of Internet sites and the content of their medical information for physicians and patients using the example "soft tissue sarcoma." METHODS: Sixteen German and English Internet search engines were used to evaluate the retrieved internet sites regarding their target group, publisher, contents, and topicality. RESULTS: The majority of retrieved websites were in English compared to significantly fewer in German. The content of information was more valuable for patients and physicians on the English websites compared to the German ones. Even if many of the evaluated websites originated from medical organizations or universities, the amount of information was limited and often not up to date. CONCLUSION: Information on the web is widespread, but for special queries too limited and difficult to identify. An improvement of available websites is needed, especially those maintained by universities and nonprofit medical organizations. The retrieval software should be optimized to ease identification of information, which should be validated by a recognized standard.

Humans↗

Mediastinal lymphadenectomy in non-small cell lung cancer: effectiveness in patients with or without nodal micrometastases - results of a preliminary study.

OBJECTIVES: So far it has not clearly been demonstrated that systematic mediastinal lymphadenectomy improves survival in patients with non-small cell lung cancer. One explanation might be that in some patients an early spread of tumor cells has occurred which might not be curable by surgical means. To test this hypothesis lymph nodes of patients which were treated either by lymph node sampling or systematic lymphadenectomy were screened for micrometastatic spread of tumor cells and the influence of nodal micrometastases on the efficacy of lymphadenectomy was analyzed. METHODS: Lymph nodes from patients (n=94) which were included in a randomized trial of lymph node sampling (LS, n=41) versus radical systematic lymphadenectomy (LA, n=53) were screened by immunohistochemistry for disseminated tumor cells using the antibody Ber-Ep4. The median observation time was longer than 5 years and follow-up data were available from all 94 patients. Kaplan-Meier curves were calculated and tested for statistical significance using the log-rank test. RESULTS: Standard histopathological analysis revealed no lymph node involvement (pN0) in 61 patients, pN1 disease in 13 patients and pN2 disease in 20 patients without significant differences between LA and LS with respect to T-stage, N-stage or age and sex of the patients. By immunohistochemistry a minimal nodal spread of tumor cells was detected in 21 out of 94 patients (LS, n=10 (24%); LA, n=11 (21%)). Similar to the entire group of patients also in the subset of patients with nodal micrometastases the type of lymphadenectomy did not significantly influence the long-term survival (P=0.27 and P=0.39, respectively). In contrast, in patients with a negative immunohistochemical analysis systematic lymphadenectomy resulted in an improved overall survival (P=0.044). CONCLUSIONS: Our data provide some evidence that systematic lymphadenectomy improves survival in patients without an early locoregional spread of cancer cells. As long as these patients can not be identified preoperatively all patients should undergo a systematic mediastinal lymphadenectomy.

Carcinoma, Non-Small-Cell Lung↗

Effect of prenatal glucocorticoids and postnatal nitric oxide inhalation on survival of newborn rats with nitrofen-induced congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Pulmonary hypertension and pulmonary hypoplasia account for the high mortality rate associated with congenital diaphragmatic hernia (CDH). In animal models of CDH, postnatal nitric oxide (NO) inhalation resulted in significantly better survival rates and antenatal glucocorticoid administration in improved lung compliance. The objective of this study was to evaluate the combined effect of prenatal glucocorticoid administration and postnatal NO inhalation on the survival rate of newborn rats with nitrofen-induced CDH. METHODS: Right-sided CDH was induced by maternal administration of a single oral dose (100 mg, intraperitoneally) of nitrofen on day 11.5 of pregnancy. Dexamethasone (DEX, 0.25 mg/kg) was given in groups III and IV by maternal intraperitoneal injection on day 18.5 and 19.5 of pregnancy. Control animals (groups I and II) received vehicle alone. After spontaneous delivery, the newborn animals were exposed to either NO (80 ppm; groups II and IV) or room air (groups I and III). Vitality (Rat-Score), sO(2) and survival were monitored continuously for 12 hours until animals were killed. Hernia size was estimated as percentage of total thoracic content. RESULTS: Right-sided CDH was observed in 392 of 491 newborn rats (81%). Animals with large hernias (>50%) died within 4 hours after birth, irrespective of treatment. Hernias with less than 50% of the thoracic volume were considered clinically relevant hernias. In this category, 12.5% of animals without treatment (group I) survived compared with 63.6% after NO treatment alone (group II; P <.01). Survival rate after DEX treatment alone (group III) was 69.4% (group III v I; P <.01). In group IV (DEX and NO) 95.2% of the animals survived (group IV v I; P <.001). In contrast to DEX alone, NO administration resulted in significantly better sO(2)(group II and IV) compared with group I (P <.05). CONCLUSION: Combination of prenatal maternal glucocorticoids and postnatal NO inhalation significantly improved survival rate of newborn rats with nitrofen-induced CDH.

Administration, Inhalation↗

[Intussusception after Billroth II procedure--an uncommon cause of an upper gastrointestinal ileus].

We present a case of a 73-year-old male patient with Korsakow's disease who was admitted with upper gastrointestinal bleeding and recurrent vomiting. He had received partial gastric resection with Billroth II reconstruction 39 years before for recurrent ulcer disease. At gastroscopy erosive gastritis with no active bleeding and a structure-resembling necrotic mucosa suspicious for intussuscepted small bowel was seen. At exploratory laparotomy jejunogastric intussusception of 50 cm of small bowel through Braun's enteroanastomosis into the gastric remnant was found. After reposition the bowel recovered well and resection was unnecessary. As prophylaxis the bowel was partially attached by sutures in terms of a partial Noble's Operation. The patient's recovery was uneventful after surgery. Jejunogastric intussusception is a rare cause of upper gastrointestinal bleeding and ileus.

Aged↗

Heterotopic pancreatitis: gastric outlet obstruction due to an intramural pseudocyst and hamartoma.

Heterotopic pancreas, usually a silent gastrointestinal malformation, may become clinically evident when complicated by chronic inflammation. We report a case of pancreatitis and extensive pseudocyst formation in the gastric antrum, which caused gastric outlet obstruction. The diagnosis was obscured by a history of emesis during pregnancy and a previously resected gastric polyp. The nature of the obstructive lesion was not diagnosed preoperatively in spite of endosonographic evaluation. Intraoperatively, a cystic tumor of the stomach wall was found, the lesion was excised, and a pyloroplasty was performed to close the excision site. Histology revealed heterotopic pancreatic tissue with chronic inflammation, fibrosis and pseudocyst formation and adjacent to this lesion a myoglandular hamartoma. The patient is symptom-free two years after surgery and no recurrence was found. The nature of heterotopic pancreatic tissue, its diagnosis and management are discussed.

Adult↗

[MRI-based N-staging in esophageal cancer].

PURPOSE: For planning the therapeutic strategies and estimating the prognosis in esophageal cancer, N-staging is very important. To date, MRI still is of minor importance as imaging modality of the mediastinum despite promising developments in the past, like ECG-gating or "averaging" sequences, e. g., LOTA (Long-term averaging), which facilitate mediastinal and thoracic MR-imaging. In a prospective approach, the value of MRI based N-staging was examined with respect to LOTA-sequences. MATERIAL AND METHODS: Within four weeks prior to esophagectomy, standardized MRI of the esophagus was performed in 15 patients (10 squamous-cell-carcinomas and 5 adenocarcinomas) using a 1.5 T whole body scanner. Imaging quality was classified based on depiction of aortic wall or tracheal wall layers. Criteria for malignant infiltration were a diameter of more than 15 mm or a round appearance of a lymph node together with GD-DTPA enhancement. All data were blinded and separately read by two radiologists. The data of the study were compared with those from the pathological workup of the resected specimen. RESULTS: MRI had a sensitivity of 100 % and a specificity of 78 % for lymph node metastases. Due to incomplete depiction of the celiac trunk (M1), nodal metastasis in a non-enlarged node was missed. CONCLUSION: With modern MRI, N-staging is almost as accurate as the gold standard endoscopic ultrasound and should particularly be used in patients not suited for an endoscopic ultrasound examination.

Adenocarcinoma↗

Esophageal cancer: the mode of lymphatic tumor cell spread and its prognostic significance.

PURPOSE: Data on skip metastases and their significance are lacking for esophageal cancer. This issue is important to determine the extent of lymphadenectomy for esophageal resection. In this study we examined the lymphatic spread in esophageal cancer by routine histopathology and by immunohistochemistry. PATIENTS AND METHODS: A total of 1,584 resected lymph nodes were obtained from 86 patients with resected esophageal carcinoma and evaluated by routine histopathology. Additionally, frozen tissue sections of 540 lymph nodes classified as tumor-free by routine histopathology were screened for micrometastases by immunohistochemistry with the monoclonal antibody Ber-EP4. The lymph nodes were mapped according to the mapping scheme of the American Thoracic Society modified by Casson et al. RESULTS: Forty-four patients (51%) had pN1 disease, and 61 patients (71%) harbored lymphatic micrometastases detected by immunohistochemistry. Skip metastases detected by routine histopathology were present in 34% of pN1 patients. Skipping of micrometastases detected by immunohistochemistry was found in 66%. The presence of micrometastases was associated with a significantly decreased relapse-free and overall survival (56.0 v 10.0 months and > 64 v 15 months, P <.0001 and P =.004, respectively). Cox regression analysis revealed the independent prognostic influence of micrometastases in lymph nodes. Lymph node skipping had no significant independent prognostic influence on survival. CONCLUSION: Histopathologically and immunohistochemically detectable skip metastases are a frequent event in esophageal cancer. Only extensive lymph node sampling, in conjunction with immunohistochemical evaluation, will lead to accurate staging. An improved staging system is essential for more individualized adjuvant therapy.

Adult↗

Minimal residual disease in non-small-cell lung cancer.

Early metastatic relapse after complete resection (R0) of apparently localized primary tumors is frequent in patients with non-small-cell lung cancer (NSCLC). This observation indicates an occult tumor cell dissemination already present at the time of primary surgery but undetectable by current tumor staging methods. During the past 10 years ultrasensitive immunohisto-/-cytochemical and molecular assays have been developed that are able to detect single tumor cells and small tumor cell clusters present in lymph nodes classified as tumor-free by conventional histopathologic analysis, bone marrow, or peripheral blood. Here we present an overview of the incidence and prognostic impact of such early disseminated tumor cells in patients with NSCLC.

Carcinoma, Non-Small-Cell Lung↗

Three novel mutations in the RET proto-oncogene.

Medullary thyroid carcinoma (MTC) occurs as a sporadic tumor or in connection with inherited cancer syndromes of multiple endocrine neoplasia type 2 and familial MTC. Missense RET proto-oncogene mutations and small in-frame deletions are found in most of the cases. In a significant amount of sporadic MTC cases somatic mutation at codon 918 (exon 16), or at codons 609, 611, 618, 620 (exon 10), or codons 630, 634 (exon 11) appear. We report here on three new somatic cell missense mutations of the RET proto-oncogene associated with sporadic MTC. In one tumor mutation at codon 922 TCC(Ser)-->TTC(Phe) in exon 16 was found. In another tumor two mutations at codons 639 GCA(Ala)-->GGA(Gly) and 641 GCT(Ala)-->CGT(Arg) in the exon 11 were observed. Allele-specific PCR followed by sequencing demonstrated the presence of both mutations at the same allele.

Base Sequence↗