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R Hatz

Publications and source records attributed to R Hatz.

At least 19 recordsLinked to original sources
PubMed2006

Outcome following lung resections for pT1 non-small cell lung cancer.

AIMS: To analyse the outcome of patients with pT1 NSCLC treated at our institution by antero-lateral thoracotomy, anatomical lung resections and mediastinal lymph node dissection between 1980 and 2001. METHODS: Follow-up data were obtained retrospectively from 1980 to 1990 and prospectively after 1990. Survival was analysed using the Kaplan-Meier method. RESULTS: Histopathological examinations revealed mediastinal lymph node infiltration in 27.6% (pN1 17.8% and pN2 9.8%). pN2 was classified in 14.1% of adenocarcinomas compared to 6.2% of squamous cell carcinomas. Median overall survival of patients with pT1 carcinomas was 89+16 months (median+standard error). Histopathological N-classification indicates differential prognostic and therapeutic implications in pT1 adeno- and squamous cell carcinomas. CONCLUSIONS: Complete lymph node dissection is required for all patients with T1 NSCLC treated by either open surgery or VATS resection. Histopathological N-classification indicates differential prognostic and therapeutic implications in pT1 adeno- and squamous cell carcinomas.

Carcinoma, Non-Small-Cell Lung↗
PubMed2006

[Cine MRI of the thorax in patients with pectus excavatum].

BACKGROUND: Morphologic and dynamic assessment of respiratory chest kinetics was performed in patients with pectus excavatum deformity (PE) using dynamic MRI: cine MRI. MATERIAL AND METHODS: Seven consecutive patients with PE (aged 20.3 years+/-4.0) and ten healthy volunteers of comparable age underwent real-time cine MRI of the chest during breathing on a 1.5 T MR scanner (Magnetom Sonata, Siemens Medical Systems, Erlangen, Germany) using a standard phased array body coil and a half-Fourier single-shot turbo spin echo sequence (HASTE) for dynamic imaging. During deep inspiration and expiration, single-shot sequences were performed in one slice level over 20 s at a frequency of 1 image/s covering the entire thoracic cage in three orientations. Morphology and chest kinetics in patients with PE were analyzed and compared with normal values, and typical patterns of chest kinetics were noted. RESULTS: Three different types of chest morphology in PE were identified: (1) the generally flattened thoracic cage, (2) the "tilted" sternum, and (3) the focally deepened sternum. Three patterns of motion correspond to these morphological types: (1) elevation of the sternum and the anterior thoracic wall, (2) angulated elevation of the parasternal rib cage with persistent deepening of the sternum resembling a "wing beat" movement, and (3) increased diaphragmatic movements with limited chest wall dynamics. CONCLUSIONS: Cine MRI is an adequate radiation-free diagnostic modality for the dynamic imaging of both chest morphology and chest wall kinetics in patients with PE. The pectus severity index can easily be determined and three typical movement patterns of chest wall kinetics identified.

Adolescent↗
PubMed2005

Human herpesvirus 6 in bronchalveolar lavage fluid after lung transplantation: a risk factor for bronchiolitis obliterans syndrome?

Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.

Adenoviridae Infections↗
PubMed2004

Differences in the expression of LPS-receptors are not responsible for the sex-specific immune response after trauma and hemorrhagic shock.

Several studies demonstrated a sex-specific cytokine secretion by macrophages following trauma-hemorrhage (T-H) and incubation with lipopolysaccharide A (LPS). Although LPS is known to act via the receptors CD14 and TLR4 on macrophages, it remains unknown whether differences in LPS receptor expression in males and females may be responsible for the gender-specific LPS induced cytokine response following (T-H). To study this, male and proestrus female mice (C3H/HeN) were subjected to trauma (laparotomy) followed by hemorrhage or sham operation. At 2 h thereafter, SMphi and PMphi were harvested and cultured for 2 h. The expression of CD14 and TLR4 was measured by flow cytometry on unstimulated SMphi and PMphi as well as after LPS stimulation. The results indicate that the expression of CD14 and TLR4 on SMphi and PMphi from female and male mice was similar in sham-operated animals and after (T-H). Incubation of macrophages with LPS did not alter CD14 and TLR4 expression in the study groups. Thus, the sex specific LPS induced cytokine secretion after (T-H) is not caused by differences in LPS receptor expression on Mphi of male and female mice.

Animals↗
PubMed2004

[Importance of microcirculation in plastic surgery].

The article summarizes distinct microcirculatory models for use in surgical research with a special interest to plastic surgery. Methods for the quantitative analysis of the microcirculation in burns, flaps and wounds are presented. Vascularization of biomaterials can be observed by means of the dorsal skinfold chamber model in hamsters and mice. Developing capillary sprouts can be assessed by means of videomicroscopy and angiogenetic drugs can be tested using this model. Hairless mice allow for direct, long-term observation of the microcirculation in burns as well as during healing of dermal wounds. The pathophysiology of diabetic wound healing can also be studied. A mouse model to assess flap microcirculation during ischemia/reperfusion injury with special emphasis on platelet/endothelium interaction in vivo is described. Platelets adherent to the inner vessel wall are known to trigger compromised perfusion in flaps. The model allows us to test anti-thrombotic drugs. The use of a special microscopic device (OPS imaging) allows us to study the microcirculation at sites of burn injury and chronic wounds in humans. Microcirculatory research in plastic surgery has increased the understanding of the pathophysiology of vascularization of biomaterials, wound healing and ischemia/reperfusion.

Animals↗
PubMed2002

Orthogonal polarization spectral imaging versus intravital fluorescent microscopy for microvascular studies in wounds.

The aim of this study was to validate orthogonal polarization spectral (OPS) imaging against intravital fluorescence microscopy (IFM) for microvascular measurements in normal skin and during wound healing. Experiments were performed on the ears of hairless mice (N = 8). The diameter of arterioles and venules, red blood cell velocity in venules, and the functional capillary density were assessed under normal conditions using OPS imaging and IFM. After creation of a circular wound, these observations were repeated at the identical microvascular regions on days 4, 7, 10, and 15. Images were videotaped, and CapImage was used for off-line computer-assisted analysis. Using OPS imaging, the microcirculation of wounded skin in hairless mice could be observed successfully. The regression analyses against standard IFM revealed a significant (p < 0.001) correlation for measurements of all microcirculatory parameters investigated (venular diameter: r(2) = 0.98, N = 345; red blood cell velocity: r(2) = 0.51, N = 326; functional capillary density: r(2) = 0.44, N = 156). However, for diameter as well as for functional capillary density measurements, OPS imaging yielded lower absolute values compared with IFM. The authors were able to validate OPS imaging against IFM for the measurement of microvascular parameters in an animal model of skin wound healing. Such a device should now help to study the role of microcirculation in physiology and pathophysiology during wound healing in patients. First clinical investigations are promising.

Animals↗
PubMed2002

[Direct visualization of microcirculation in burn wounds with OPS imaging--is determination of depth of burns possible?].

Adjunct diagnostic techniques might help surgeons to accurately analyse the depth of a burn. However, despite all technical innovations an ideal device for such an application has not been established for routine use as yet. OPS imaging implemented into the CYTOSCAN A/R is a new, recently introduced technique which allows to obtain high contrast images of the microcirculation without the necessity for fluorescent dyes. The aim of the study was to validate OPS imaging as a tool to study microcirculation in skin after burn injury. OPS imaging was applied by no-touch technique and capillary blood flow was videotaped. Subsequent measurements of the microcirculation were performed at the identical site of the burn. Quantitative analysis of the microcirculation was performed off-line using CapImage. OPS imaging produces high quality images of the microcirculation in a burn wound. Data is given as the number of perfused capillaries per observation area (functional capillary density; FCD) [n/cm2]. OPS imaging allows for direct in vivo visualization and quantification of the microcirculation in burned skin. Our preliminary results of the use of OPS imaging in assessing the microcirculation in burns appear promising, and we hope that this novel technique will allow to improve the knowledge of the dynamics of the microcirculation in the pathophysiology of thermal injury.

Blood Flow Velocity↗
PubMed2001

Assessing the microcirculation in a burn wound by use of OPS imaging.

We report on the use of OPS imaging to visualize the microcirculation in a burn wound. This novel technique produces high quality images of the microcirculation and quantitative analysis of functional capillary density (FCD) was possible. FCD measured at day 3 following the injury was 11.2 +/- 4.6 (n/mm superset2; mean +/- SEM). During the initial phase of healing microcirculatory changes were characterized by a moderate but steady increase of FCD, which showed marked increase beginning from day 12 following the burn (16.6 +/- 6.9). Maximal FCD measured at day 23 (48.2 +/- 19.7) decreased from this point in time to finally reach 25.2 +/- 10.3 n/mm superset2 at the end of observation. OPS imaging allows for direct in vivo visualization and quantification of the microcirculation in burned skin. Our results of the use of OPS imaging in assessing the microcirculation in a burn wound appear promising, and we hope that this novel technique will allow to improve the knowledge of the dynamics of the microcirculation in the pathophysiology of thermal injury.

Adult↗
PubMed2000

Helicobacter pylori infections--are these diseases relevant for surgical treatment?

Helicobacter pylori infection and its strong association with gastroduodenal diseases has revolutionized our views and treatment options in these diseases. Surgery has always been considered a mainstay in their treatment. The development of potent eradication regimes has changed indications for operative treatment. With endoscopic procedures being increasingly performed by the surgeon himself, it has become necessary that he educate himself in the diagnosis and treatment of H. pylori infection in order to be able to cope with these diseases in every day surgical practice. Treatment of H. pylori infection may not only be seen as an alternative to operative therapy, but also as an adjunct following surgical treatment of gastroduodenal disease.

Duodenitis↗
PubMed1999

Effect of immunization on gastrin release in rat antrum mucosa.

Helicobacter pylori (H.P.) infection is the main cause of chronic active gastritis and is closely associated with peptic ulcer disease. Chronic hypergastrinaemia is known to be induced in patients infected with this pathogen. Gastrin is the most potent stimulator of gastric acid secretion. In animals infected with H.P. or H. felis vaccination against H.P.can eliminate the bacterium and alleviate associated gastritis. However little is known on the influence of immunization regimes on gastrin release. The aim of this study was to evaluate the effect of systemic immunization on gastrin release in a rat model, using a well defined but for the rat unknown protein. OVA-immunized and non immunized animals received OVA intragastrically in vivo, and serum gastrin was measured. Stimulation with bovine serum albumin (BSA) served as control. In vitro single cell suspensions of the antrum mucosa and mucosal fragments of immunized and non immunized animals were also incubated with OVA and BSA. The results show specific significant gastrin suppression after immunization and antigen feeding. The same results were obtained in the model of mucosa fragments but not in single cell suspensions. This hypothesized that gastric suppression could be mediated by mast cells or T-helper two cells (TH2) in the mucosal layer of the stomach. A single cell suspension is not suitable for studying immunologically mediated gastrin release because direct cell contact is necessary. Further studies with these animal models have to show whether effects seen by vaccination could be mediated by induction of gastrin suppression and studies on human tissues are necessary to show possible similar effects with H.P.

Animals↗
PubMed1999

Colonic mucosal proliferation is related to serum deoxycholic acid levels.

BACKGROUND: Hyperproliferation of the colorectal mucosa is regarded as an early step in colorectal carcinogenesis. Deoxycholic acid, a secondary bile acid, stimulates colorectal epithelial proliferation in animals and is considered a tumor promoter in human colorectal carcinogenesis. The aim of this study was to investigate the correlation between colorectal mucosal proliferation and the serum deoxycholic acid level. METHODS: From each of 19 patients (10 men and 9 women) with (n = 3) or without (n = 16) colorectal adenoma, 18 biopsy specimens were obtained by colonoscopy, 3 from each of the 6 colonic segments. A crude nuclei fraction was prepared, and DNA was stained by propidium iodide to determine the proliferative index (the percentage of cells in the S and G2/M phases of the cell cycle) by flow cytometry. Serum levels of deoxycholic acid were determined by gas-liquid chromatography. RESULTS: The colonic proliferation rates (median of the values obtained in all segments, 14.1%; range, 10.0-18.7%) and the fasting serum deoxycholic acid levels (median, 0.86 micromol/L; range, 0.28-1.58 micromol/L) showed a significant correlation (r = 0.51, P = 0.03). Serum lithocholic, cholic, chenodeoxycholic, and ursodeoxycholic acid levels were not correlated with the proliferation rates. CONCLUSIONS: Levels of deoxycholic acid in serum are correlated with the rates of the colorectal mucosa. These results are consistent with the concept that deoxycholic acid promotes colorectal carcinogenesis.

Adenoma↗
PubMed1998

Gastric carcinoma risk index in patients infected with Helicobacter pylori.

Epidemiological data show an association between Helicobacter pylori gastritis and gastric carcinoma. However, most people infected with H. pylori do not develop gastric cancer. We have therefore evaluated histological criteria indicating an increased risk for gastric cancer. H. pylori gastritis was investigated in 117 patients with small (O<2 cm) early gastric carcinomas and in 117 age-matched duodenal ulcer patients infected with H. pylori, who are known to have a low risk for developing gastric carcinoma. The results showed that infiltration with lymphocytes/plasma cells and infiltration with neutrophils predominating in the corpus, and intestinal metaplasia in antrum and corpus were associated with both types of gastric carcinoma (intestinal and diffuse, P<0.0001). If an index is computed by giving one point to each of these features, the predictive value for the presence of gastric carcinoma was 0.79 with a score of 2, and 0.94 with a score of 3 (all points on the index used). Application of this index might be a simple method of identifying patients infected with H. pylori and carrying a higher risk for gastric carcinoma.

Adult↗
PubMed1998

Severe expression of corpus gastritis is characteristic in gastric cancer patients infected with Helicobacter pylori.

In 50 Helicobacter pylori-infected gastric carcinoma patients the corpus gastritis was significantly higher than in matched H. pylori-positive control subjects (P < 0.01). Atrophy and intestinal metaplasia (IM) occurred significantly more often in the antrum of carcinoma patients (P < 0.01). The odds ratio for gastric carcinoma was 8.85 for high-grade corpus gastritis and 8.04 when atrophy in the antrum was present.

Female↗
PubMed1998

Double-blind trial of omeprazole and amoxicillin in the cure of Helicobacter pylori infection in gastric ulcer patients. The Ulcer Study Group, Germany.

BACKGROUND: Our aim was to investigate the efficacy of omeprazole and amoxicillin in curing Helicobacter pylori infection in gastric ulcer patients. METHODS: In a double-blind trial 185 H. pylori-positive gastric ulcer patients were prospectively randomized to receive 40 mg omeprazole twice daily and either 750 mg amoxicillin three times daily or 750 mg amoxicillin placebo three times daily on days 1-14, followed by 20 mg omeprazole daily on days 15-56. RESULTS: Twenty-seven patients were excluded because of lack of compliance or missed follow-up examinations; one patient receiving amoxicillin discontinued treatment owing to side effects. On an intention-to-treat basis, omeprazole/amoxicillin led to cure of H. pylori infection in 67.1% (47 of 70) of patients not using non-steroidal anti-inflammatory drugs (NSAIDs)/aspirin (ASA) and in 46.7% (14 of 30) of those taking NSAIDs/ASA (P < 0.05). With the omeprazole/placebo regimen, H. pylori infection was cured in 8.8% (no NSAIDs), and 0% (NSAIDs). CONCLUSIONS: The use of NSAIDs/ASA may limit the efficacy of omeprazole/amoxicillin in curing H. pylori infection in gastric ulcer patients.

Adolescent↗
PubMed1997

Differing degree and distribution of gastritis in Helicobacter pylori-associated diseases.

Infection with Helicobacter pylori (H. pylori) causes gastritis, and may be associated with gastric and duodenal ulcers and also with such malignant diseases as MALT lymphoma and gastric carcinoma. In order to determine whether there are differences in the degree and distribution of gastritis, each patient with H. pylori gastritis only (n = 50) was matched for sex and age with four patients, one each with H. pylori-associated duodenal ulcer, gastric ulcer, gastric carcinoma or MALT lymphoma. From each patient, two biopsies were taken from the antrum and two from the corpus for histopathological examination of H. pylori gastritis. The median summed gastritis score decreases in the following order: antrum: gastric ulcer > duodenal ulcer > gastritis alone > carcinoma > MALT lymphoma, and corpus: gastric ulcer > carcinoma > MALT lymphoma > gastritis alone and duodenal ulcer. We conclude that the degree and distribution of H. pylori gastritis differs significantly among H. pylori-associated diseases. These differences may explain some of the underlying pathomechanisms associated with H. pylori infection.

Adult↗
PubMed1997

Is the polymerase chain reaction or cure of Helicobacter pylori infection of help in the differential diagnosis of early gastric mucosa-associated lymphatic tissue lymphoma?

PURPOSE: The differential diagnosis of early gastric mucosa-associated lymphatic tissue (MALT) lymphoma based on Helicobacter pylori gastritis may be difficult when lymphoepithelial lesions are not detected. The aim of the present study was to investigate the question whether the polymerase chain reaction (PCR) or cure of H pylori infection may be of help in this respect. PATIENTS AND METHODS: Twenty patients with suspected low-grade gastric MALT lymphomas were treated in a double-blinded, randomized, crossover trial with 2,250 mg of either amoxicillin or placebo, both in combination with omeprazole, for 14 days with the aim to cure H pylori infection. PCR was performed using primers specific for the CDR3 region to detect monoclonal B cells. RESULTS: In five of 20 patients, MALT lymphomas were finally diagnosed. Three of these five patients went into complete remission, while two were referred to surgery. In the 15 patients with gastritis, complete regression was observed in all cases. With respect to PCR, monoclonal bands were detected in all four of the analyzed lymphoma patients before histology showed lymphoma. In addition, monoclonal bands were found in three patients with gastritis. In the patients with gastritis and monoclonal PCR, complete regression took longer as compared with the remaining 12 patients with polyclonal PCR and gastritis (P = .0209). Successful H pylori eradication was associated with earlier diagnosis of the MALT lymphoma (P = .0237). CONCLUSION: CDR3-PCR may be of help in the differential diagnosis of early gastric MALT lymphoma. Furthermore, H pylori eradication may lead to earlier diagnosis.

Adult↗
PubMed1997

[Surgical interventions in extracorporeal membrane oxygenation (ECMO)].

Extracorporeal membrane oxygenation is a suitable technique for short-term treatment of resistant respiratory failure with a comparably low mortality rate of 32%. However, pulmonary complications are quite often encountered during ECMO therapy making thoracic interventions necessary. The most frequent of these complications is hemorrhage followed by lung fistula, which remain resistant to conventional therapy. The indication for operative lung resection during ECMO treatment must remain restricted to selected cases, since these procedures have a high morbidity.

Adult↗