[Neutrophils in the tumor microenvironment-foes or friends?] / Neutrophile Granulozyten im Tumormikromilieu ­ Feind oder Freund?

Neutrophils are the most abundant white blood cells in the human circulation and are usually associated with inflammation and with fighting infections. In recent years, the role of these cells during cancer progression has been a matter of increasing interest. Tumor-associated neutrophils (TANs) accumulate in cancer patients and represent an important negative prognostic marker in a broad variety of neoplasms. Accordingly, TANs represent a highly attractive therapeutic target. TAN may exhibit tumor-promoting or -inhibiting functions. Pro-tumor neutrophils support tumor angiogenesis and growth and promote metastatic dissemination of tumors via establishment of the premetastatic niche. Studies in animal models have already shown that the depletion of TANs or the inhibition of their migration bears therapeutic potential. Multiple pathways and mediators that induce pro-tumoral functions in neutrophils have been identified. In this review, we provide an up-to-date overview of the pro- and anti-tumor properties of neutrophils as well as the environmental cues that regulate these distinct functions. We also report on our own work that comprehensively investigated the role of neutrophils in head and neck cancer.

Metabolite profiles evaluated, according to sex, do not predict resting energy expenditure and lean body mass in healthy non-obese subjects.

PURPOSE: Differences in resting energy expenditure (REE) between men and women mainly result from sex-related differences in lean body mass (LBM). So far, a little is known about whether REE and LBM are reflected by a distinct human metabolite profile. Therefore, we aimed to identify plasma and urine metabolite patterns that are associated with REE and LBM of healthy subjects. METHODS: We investigated 301 healthy male and female subjects (18-80 years) under standardized conditions in the cross-sectional KarMeN (Karlsruhe Metabolomics and Nutrition) study. REE was determined by indirect calorimetry and LBM by dual X-ray absorptiometry. Fasting blood and 24 h urine samples were analyzed by targeted and non-targeted metabolomics methods using GC × GC-MS, GC-MS, LC-MS, and NMR. Data were evaluated by predictive modeling of combined data using different machine learning algorithms, namely SVM, glmnet, and PLS. RESULTS: When evaluating data of men and women combined, we were able to predict REE and LBM with high accuracy (> 90%). This, however, was a clear effect of sex, which is supported by the high degree of overlap in identified important metabolites for LBM, REE, and sex, respectively. The applied machine learning algorithms did not reveal a metabolite pattern predictive of REE or LBM, when analyzing data for men and women, separately. CONCLUSIONS: We could not identify a sex independent predictive metabolite pattern for REE or LBM. REE and LBM have no impact on plasma and urine metabolite profiles in the KarMeN Study participants. Studies applying metabolomics in healthy humans need to consider sex specific data evaluation.

High frequency of herpesvirus-specific clonotypes in the human T cell repertoire can remain stable over decades with minimal turnover.

High-throughput T cell receptor sequencing on sequentially banked blood samples from healthy individuals has shown that high-frequency clonotypes can remain relatively stable for up to 18 years, with minimal inflation, deflation, or turnover. These populations included T cell expansions specific for Epstein-Barr virus. Thus, in spite of exposure to a barrage of microorganisms over the course of life, the dominant clonotypes in the mature peripheral T cell repertoire can alter surprisingly little.

Ultrafast energy transfer and structural dynamics in DNA.

Ultrafast structural dynamics concomitant to excitation energy transfer in DNA has been studied using a pair of pyrene-labeled DNA bases. The temporal evolution of the femtosecond pump-probe spectra reveals the existence of two electronic coupling pathways, through-base stack and through-space, which lead to excitation energy transfer and excimer formation even when the labeled DNA bases are separated by one AT base pair. The electronic coupling which mediates through-base stack energy transfer is so strong that a new absorption band arises in the excited-state absorption spectrum within 300 fs. From the analysis of time-dependent spectral shifts due to through-space excimer formation, the local structural dynamics and flexibility of DNA are characterized on the picosecond and nanosecond time scale.

Apoptosis of inflammatory cells in immune control of the nervous system: role of glia.

The elimination of inflammatory cells within the central nervous system (CNS) by apoptosis plays an important role in protecting the CNS from immune-mediated damage. T cells, B cells, macrophages, and microglia all undergo apoptosis in the CNS. The apoptotic elimination of CNS-reactive T cells is particularly important, as these cells can recruit and activate other inflammatory cells. T-cell apoptosis contributes to the resolution of CNS inflammation and clinical recovery from attacks of experimental autoimmune encephalomyelitis (EAE), an animal model of the demyelinating disease multiple sclerosis (MS). T-cell apoptosis in the CNS in EAE occurs in both an antigen-specific and an antigen-nonspecific manner. In antigen-specific T-cell apoptosis, it is proposed that T cells that recognize their antigen in the CNS, such as CNS-reactive T cells, are deleted by the process of activation-induced apoptosis after activation of the T-cell receptor. This may result from the ligation of T-cell death receptors (such as CD95 (Fas) or tumor necrosis factor (TNF) receptor 1) by CD95 ligand (CD95L) or TNF expressed by the same T cell or possibly by microglia, astrocytes or neurons. Inadequate costimulation of the T cell by antigen-presenting glial cells may render T cells susceptible to activation-induced apoptosis. T cells expressing CD95 may also die in an antigen-nonspecific manner after interacting with glial cells expressing CD95L. Other mechanisms for antigen-nonspecific T-cell apoptosis include the endogenous release of glucocorticosteroids, deprivation of interleukin-2, and the release of nitric oxide by macrophages or glia. Apoptosis of autoreactive T cells in the CNS is likely to be important in preventing the development of autoimmune CNS diseases such as MS.

Influence of pneumoperitoneum and patient positioning on respiratory system compliance.

STUDY OBJECTIVE: To investigate the influence of pneumoperitoneum (PP) and posture on respiratory compliance and ventilation pressures. DESIGN: Prospective, single blind trial. PATIENTS: 10 female ASA physical status I and II patients scheduled for elective gynecologic laparoscopy. SETTING: University medical center. INTERVENTIONS: Anesthesia was performed as total IV anesthesia (TIVA) with propofol, alfentanil, and atracurium. After induction of anesthesia and orotracheal intubation, the lungs were ventilated to maintain partial pressure of CO(2) (P(ET)CO(2)) of 30 +/- 3 mmHg. Ventilation was kept constant. As gas mixture oxygen and air 1:1 was used without positive end-expiratory pressure (PEEP). MEASUREMENTS: Measurements were taken before and after creation of pneumoperitoneum with an intraabdominal pressure (IAP) of 10 mmHg, of 15 mmHg in 20 degrees head-down tilt, then in 20 degrees head-up tilt, and after deflation of PP. We determined peak inspiratory pressure (PIP), mean airway pressure (mPaw), P(ET)CO(2), expiratory minute volume (V(E)), heart rate (HR), and systolic (SBP), diastolic (DBP), and mean arterial pressure (MAP). Respiratory system compliance (C(eff rs)) was calculated as quotient of tidal volume (V(T)) and PIP. MAIN RESULTS: After creation of PP (IAP 10 mmHg), there was a significant increase of median PIP (3 cmH(2)O), mPaw (1 cm H(2)O) and arterial pressure (BP), (MAP by 7 mmHg), C(eff rs) decreased by 6 mL. cm H(2)O(-1). Increase of IAP to 15 mmHg led to a further increase of PIP (2 cm H(2)O) and mPaw (1 cm H(2)O), and a further decrease of C(eff rs) by 5 mL cm H(2)O(-1); BP decreased (MAP by 5.5 mmHg). Head-up or head down positions showed no significant hemodynamic or pulmonary changes. P(ET)CO(2)increased from 29.5 to 36 mmHg at an IAP of 15 mmHg, but then no further changes were noticed. Five minutes after deflation of pneumoperitoneum all values returned to baseline levels. CONCLUSIONS: Creation of PP at an IAP of 15 mmHg reduced respiratory system compliance, and increased peak inspiratory and mean airway pressures, which quickly returned to normal values after deflation. Head-down or head-up position did not further alter those parameters.

Microarrays of bladder cancer tissue are highly representative of proliferation index and histological grade.

The number of genes suggested to play a role in cancer biology is rapidly increasing. To be able to test a large number of molecular parameters in sufficiently large series of primary tumours, a tissue microarray (TMA) approach has been developed where samples from up to 1000 tumours can be simultaneously analysed on one glass slide. Because of the small size of the individual arrayed tissue samples (diameter 0.6 mm), the question arises of whether these specimens are representative of their donor tumours. To investigate how representative are the results obtained on TMAs, a set of 2317 bladder tumours that had been previously analysed for histological grade and Ki67 labelling index (LI) was used to construct four replica TMAs from different areas of each tumour. Clinical follow-up information was available from 1092 patients. The histological grade and the Ki67 LI were determined for every arrayed tumour sample (4x2317 analyses each). Despite discrepancies in individual cases, the grade and Ki67 information obtained on minute arrayed samples were highly similar to the data obtained on large sections (p<0.0001). Most importantly, every individual association between grade or Ki67 LI and tumour stage or prognosis (recurrence, progression, tumour-specific survival) that was observed in large section analysis could be fully reproduced on all four replica TMAs. These results show that intra-tumour heterogeneity does not significantly affect the ability to detect clinico-pathological correlations on TMAs, probably because of the large number of tumours that can be included in TMA studies. TMAs are a powerful tool for rapid identification of the biological or clinical significance of molecular alterations in bladder cancer and other tumour types.

Influence of pneumoperitoneum and patient positioning on preload and splanchnic blood volume in laparoscopic surgery of the lower abdomen.

STUDY OBJECTIVE: To determine the hemodynamic effects of pneumoperitoneum and patient positioning during laparoscopic surgery of the lower abdomen. DESIGN: Prospective study. SETTING: University-affiliated medical center. PATIENTS: 10 ASA physical I and II female patients scheduled for laparoscopic surgery of the lower abdomen. INTERVENTIONS: Patients were anesthetized with propofol and an alfentanil infusion, then intubated, and normoventilated. MEASUREMENTS: After intubation, a transesophageal multiplane probe for measurements of right (RVESA) and left (LVESA) ventricular end-systolic and end-diastolic areas (RVEDA and LVEDA) and ejection fraction area (RVEFa, LVEFa) was introduced; heart rate (HR) and noninvasive blood pressure (BP) were recorded every minute. Ventilation was not changed during the measurements. A transvaginal ultrasound probe was inserted to measure the diameter of the common iliac vein. Measurements were performed 15 minutes after induction of anesthesia and while patients were in the supine position (P 0), 10 minutes after CO(2) insufflation to 10 mmHg IA pressure (P 10), 10 minutes after a further increase to 15 mmHg (P 15), 10 minutes after 20 degrees Trendelenburg (P 15 T), and 20 degrees reverse Trendelenburg positions (P 15 RT). Data are shown as medians, 25th to 75th percentiles, and comparisons between P 0, P 10, P 15, and P15 T were made with the Friedman test, followed by Wilcoxon test, when significant. Data at P 15 T, P 15 RT, and P 15 were compared using the Wilcoxon test, with a p-value < 0.05 regarded as significant. MAIN RESULTS: Pneumoperitoneum at 10 mmHg abdominal pressure caused a significant increase of LVESA by 78% (RVESA: 61%) and LVEDA by 48.5% (RVEDA: 45%). The diameter of the common iliac vein was decreased by 6%. A further increase of abdominal pressure to 15 mmHg led to an additional increase of 20% (LVESA) and 17% (LVEDA). Mean arterial pressure increased by a significant 7% at P 10, decreasing subsequently by 5% at P 15. The Trendelenburg position did not alter any hemodynamic findings. Reverse Trendelenburg position, however, caused a significant LVEDA-and RVEDA-decrease by 18% and 27%, respectively, and an increase in the diameter of the common iliac vein by 22%. The LVEFa and RVEFa decreased significantly after abdominal CO(2) insufflation by 18% each (P 10) without further change. CONCLUSIONS: The lithotomy position and subsequent pneumoperitoneum increased preload, probably as a result of blood shifting from the abdomen to the thorax by compression of splanchnic vessels caused by the pneumoperitoneum. Careful fluid management, maintaining low abdominal pressure, and use of the reverse Trendelenburg position are favored to prevent adverse hemodynamic effects in laparoscopic surgery.

High-throughput tissue microarray analysis of 3p25 (RAF1) and 8p12 (FGFR1) copy number alterations in urinary bladder cancer.

Studies by comparative genomic hybridization revealed that the chromosomal regions 3p25 and 8p11-p12 are recurrently amplified in bladder cancer. To investigate the prevalence of DNA copy number alterations in these chromosomal regions and study their clinical significance, we used probes for the RAF1 (3p25) and FGFR1 (8p12) genes for fluorescence in situ hybridization. A tissue microarray containing 2317 tumors was analyzed. The analysis revealed RAF1 amplification in 4.0% and FGFR1 amplification in 3.4% of interpretable tumors. In addition, deletions were found at the 3p25 locus in 2.2% and at the 8p11-12 locus in 9.9% of interpretable tumors. Both amplifications and deletions of RAF1 and FGFR1 were significantly associated with high tumor grade (P < 0.0001), advanced stage (P < 0.0001), and poor survival (P < 0.05) if tumors of all of the stages where analyzed together. RAF1 amplifications were associated with subsequent tumor progression in pT1 carcinomas (P < 0.05). The marked differences in the frequency of all of the analyzed changes between pTa grade 1/grade 2 and pT1-4 carcinomas support the concept of these tumor groups representing different tumor entities.

Association of an RNA kissing complex analyzed using 2-aminopurine fluorescence.

The fluorescent probe, 2-aminopurine-2'-O-methyl riboside (2-AP) has been selectively incorporated at adenosine positions in stem-loops (so called R1inv and R2inv), derived from the ColE1 plasmid encoded RNA I and RNA II transcripts, that interact to form stable loop-loop kissing complexes and bind the RNA one modulator (Rom) protein, such that fluorescence-detected stopped-flow and equilibrium methods could be used to study the detailed mechanism of this RNA-RNA interaction. Formation of loop-loop kissing complexes between R1inv and R2inv hairpins, substituted with 2-AP at positions in the complementary loops, results in a 5-10-fold fluorescence emission decrease (F(max) = 370 nm), which provides a sensitive measure for the binding reaction. The 2-AP substituted complexes are found to have equilibrium binding properties (average K(D) = 2.6 +/- 1.7 nM) and affinity for Rom (average K(D) = 60 +/- 24 nM) that are similar to complexes formed with equivalent unlabeled hairpins. Using stopped-flow experiments, it was found that the 2-AP probes experienced at least three different microenvironments during association of the RNA complex, thus suggesting a kinetic intermediate in the kissing pathway. In contrast, dissociation of the complex was found to fit a single exponential decay (average k(off) = 8.9 x 10(-5) s(-1)). Consistent with these observations, a two-step mechanism for RNA loop-loop complex association is proposed in which the complementary loops of R1inv and R2inv first base pair to form the loop-loop helix (average k(1) = 0.13 microM(-1)s(-1)) in the initial encounter reaction, and subsequently isomerize to the final tertiary fold in a second slower step (average k(2) = 0.09 s(-1)), where the helical stacking around the junctions is optimized.

How covert are covertly manipulated diets?

OBJECTIVE: To quantitatively assess subjects' ability to detect hedonic (palatability), sensory and nutritional differences between covertly manipulated high-fat (HF) and low-fat (LF) diets. SUBJECTS AND DIETS: This study examined the response of 16 subjects (eight men, eight women) to 20 LF and 20 HF versions of manipulated foods. Average percentage protein:fat:carbohydrate (by energy) and energy density (ED) of the two diets were 13:25:62, 371 kJ/100 g and 13:50:37, 672 kJ/100 g, respectively. PROTOCOL: Subjects were asked to simultaneously assess the HF and LF versions of each food in terms of (i) subjective pleasantness of each food, (ii) perceived differences in appearance, smell, taste and texture of the foods, and (iii) for each sample to assess whether it was high or low in energy, protein, carbohydrate, fat, fibre, sugar and salt. ANALYSIS: Perceived pleasantness of HF and LF versions of the foods was compared by analysis of variance. Comparisons used chi-squared tests of independence to assess departure from the null hypothesis of no perceived difference in remaining parameters (ii-iii). RESULTS: On average, subjects exhibited no significant preference for LF or HF versions of the foods (no difference 15 foods, three HF foods more pleasant, two LF foods more pleasant (P<0.03)). On average there were no general differences in comparison of sensory attributes that were consistently ascribable to the LF or HF foods, although there were numerous significant differences for individual foods. Subjects appeared unable to distinguish the HF foods as being HF (66% of estimates) and guessed correctly 33% of the time. They were better able to categorize the LF foods correctly (53% correct). On aggregate 43% of HF and LF foods were correctly identified. Subjects appeared able to detect sensory differences between foods but not to relate them to energy or nutrient content of these foods. CONCLUSIONS: These data suggest that subjects are on average not able to perceive large differences in the fat content of diets manipulated in this manner. In general the assumption that the manipulation of such foods is covert appears to hold, but subjects were far better at correctly identifying certain food types (dairy-based) over others.

[Hemodynamic effects of pneumoperitoneum in lithotomy position]. / Hämodynamische Auswirkungen eines Pneumoperitoneums in Steinschnittposition.

AIM OF STUDY: The study investigates the haemodynamic effects of the varying intraabdominal pressures and patient positions during gynecological procedures employing pneumoperitoneum in lithotomy positions. METHODS: TEE was used to determine end-diastolic and end-systolic left ventricular surface areas and ejection fractions were calculated from these data. To evaluate intraabdominal volume shifts the diameter of the internal iliac vein was measured by mean of vaginal ultrasound. RESULTS: In the horizontal lithotomy position both LVEDA and LVESA increased when intraabdominal pressure increased by 10 and 15 mmHg, respectively. LVAEF significantly decreased when intraabdominal pressure increased by 15 mmHg. Also DVII decreased. In Trendelenburg position there was no change in LVEDA, LVESA, LVAEF and DVII. In Anti-Trendelenburg position LVEDA and LVESA decreased. However, LVAEF remained constant and DVII increased. CONCLUSION: The increase of the intraabdominal pressure in the lithotomy position results in an increase in intrathoracic volume and an decrease in LVAEF via elevation of the the lower extremities and compression of the splanchnic vessels. There are no changes in Trendelenburg position. However, in Anti-Trendelenburg position, gravity results in a decrease in intrathoracic blood volume. In the decreased, dilatated heart the increase in intrathoracic volume may increase myocardial wall tension and hence oxygen demand, ultimately leading to an acute heart failure. As a result laparoscopic procedures in horizontal lithotomy position should be avoided in patients with dilatative cardiomyopathy.

High-throughput tissue microarray analysis of cyclin E gene amplification and overexpression in urinary bladder cancer.

Studies by comparative genomic hybridization revealed that the 19q13 chromosomal region is frequently amplified in bladder cancer. The cyclin E gene (CCNE), coding for a regulatory subunit of cyclin-dependent kinase 2, has been mapped to 19q13. To investigate the role of cyclin E alterations in bladder cancer, a tissue microarray of 2,317 specimens from 1,842 bladder cancer patients was constructed and analyzed for CCNE amplification by fluorescence in situ hybridization and for cyclin-E protein overexpression by immunohistochemistry. Fluorescence in situ hybridization analysis showed amplification in only 30 of the 1,561 evaluable tumors (1.9%). Amplification was significantly associated with stage and grade (P: < 0.0005 each). Immunohistochemically detectable cyclin E expression was strong in 233 (12.4%), weak in 354 (18.9%), and negative in 1, 286 of the 1,873 interpretable tumors. The majority (62.1%) of CCNE-amplified tumors were strongly immunohistochemistry-positive (P: < 0.0001). The frequency of protein expression increased from stage pTa (22.2%) to pT1 (45.5%; P: < 0.0001) but then decreased for stage pT2-4 (29.4%; P: < 0.0001 for pT1 versus pT2-4). Low cyclin E expression was associated with poor overall survival in all patients (P: < 0.0001), but had no prognostic impact independent of stage. It is concluded that cyclin E overexpression is characteristic to a subset of bladder carcinomas, especially at the stage of early invasion. This analysis of the prognostic impact of CCNE gene amplification and protein expression in >1,500 arrayed bladder cancers was accomplished in a period of 2 weeks, illustrating how the tissue microarray technology remarkably facilitates the evaluation of the clinical relevance of molecular alterations in cancer.

Carcinogen-modified dendritic cells induce immunosuppression by incomplete T-cell activation resulting from impaired antigen uptake and reduced CD86 expression.

Exposure of the skin to environmental stimuli, such as chemical or physical carcinogens, modifies the local skin environment, including depletion of epidermal Langerhans' cells (LC). Any subsequent exposure of the LC-depleted skin to antigen results in the generation of antigen-specific tolerance. In this study we evaluated the antigen-bearing cells in the draining lymph nodes by capitalizing on the fluorescent nature of the contact sensitizer, fluorescein isothiocyanate (FITC). When FITC was applied to the skin of normal mice, two distinct populations of antigen-bearing cells were identified in the draining lymph nodes. They were classified as either FITChi or FITClo on the basis of their fluorescence intensity and thus the amount of antigen they internalized. Only FITClo cells were detected in the lymph nodes draining FITC-treated murine skin that had been depleted of epidermal LC by prior treatment with the complete carcinogen 9,10-dimethyl 1,2-benzanthracene (DMBA). Functional analysis of these cells revealed that the FITChi cells, but not the FITClo cells, induced antigen-specific T-cell proliferation. Further analysis of the FITClo cells from the DMBA-treated mice demonstrated that these cells had reduced levels of CD80 expression, had substantially reduced levels of CD86 expression and performed poorly as co-stimulator cells in an anti-CD3-mediated proliferative assay. Nonetheless these cells still induced early signs of T-cell activation and interleukin-12 production. Consequently the FITClo cells migrating from the LC-depleted skin, through a combination of reduced antigen presentation and reduced co-stimulatory activity, induced a state of unresponsiveness or anergy in the responder T cells in a similar manner to that observed when antigen presentation occurs in the absence of co-stimulation. We propose that these unresponsive, or anergic cells, account for the antigen-specific tolerance observed in these experiments.

Focal loss of CD44 variant protein expression is related to recurrence in superficial bladder carcinoma.

The majority of papillary transitional cell carcinomas of the bladder are localized tumors at initial diagnosis; identification of those developing recurrence and an aggressive behavior is important. CD44 variant proteins have been implicated in tumor progression and metastasis, and a correlation with adverse prognosis has been demonstrated in a variety of human tumors. Here, the usefulness of conventional CD44 protein immunohistochemistry as a prognostic parameter for recurrence of superficial transitional cell carcinomas was assessed in paraffin sections of 241 tumors with long-term follow-up. A highly significant association was found between focal loss of CD44v3 and -v6 immunostaining and short recurrence-free interval in noninvasive (pTa) transitional cell carcinomas (P = 0.005), but not in minimally invasive (pT1) carcinomas (P = 0.78). Our results indicate the value of conventional CD44 immunohistochemistry as an additional tool for identifying patients at high risk for recurrence of pTa transitional cell carcinomas. They also point to biological differences between noninvasive and minimally invasive transitional cell carcinomas of the bladder.

Cyclin D1 overexpression lacks prognostic significance in superficial urinary bladder cancer.

The biological behaviour of urinary bladder neoplasms cannot be adequately predicted by histological criteria alone. Cyclin D1 is a cell-cycle regulating protein known to be overexpressed in a proportion of bladder carcinomas. To evaluate the prognostic significance of cyclin D1 expression and its relationship with tumour phenotype, 392 bladder carcinomas were analysed by immunohistochemistry. Clinical follow-up information was available in 337 patients with superficial bladder tumours (stages pTa/pT1). Cyclin D1 positivity was seen in 176 of 392 carcinomas. Cyclin D1 overexpression was strongly linked to papillary tumour growth, low stage, and low histological grade (p<0.005 each). Multivariate analysis showed that papillary tumour growth was the only parameter which was independently linked to cyclin D1 positivity. There was no significant difference in proliferative activity (Ki67 labelling index) between cyclin D1-negative and -positive tumours. Cyclin D1 positivity was not linked to the risk of recurrence or tumour progression, either in pTa or in pT1 carcinomas. It is concluded that cyclin D1 positivity distinguishes a large subgroup of papillary bladder tumours, but there is no evidence of prognostic significance for increased cyclin D1 expression.

Polysomies but not Y chromosome losses have prognostic significance in pTa/pT1 urinary bladder cancer.

A disturbed cellular DNA content is of potential diagnostic and prognostic relevance in urinary bladder cancer. To evaluate the prognostic significance of individual chromosomal aberrations in superficial bladder cancer, specimens of 105 tumors (67 pTa, 38 pT1) were examined by fluorescence in situ hybridization (FISH). FISH allows quantitation of chromosomes on a cell by cell level. Centromere probes for the chromosomes Y, 1, and 17 were used. There was a strong association between polysomies of the chromosomes 1 (found in 46% of tumors) and 17 (40% of tumors, P < .0001). Polysomies (1 and 17) were significantly more frequent in pT1 than in pTa tumors (P < .0001 each). In pTa tumors, polysomies of both chromosomes were linked to a high risk of recurrences; polysomy 17 was associated with an increased risk of progression (P < .05 each). There was no significant association between polysomies and an unfavorable prognosis in pT1 carcinomas. Previous studies had suggested a prognostic role of Y losses in bladder cancer. However, Y losses were not linked to recurrences or tumor progression in pTa or pT1 tumors of 67 male patients. These data show that marked genetic differences exist between pTa and pT1 carcinomas. They also indicate that polysomies of different chromosomes may have prognostic relevance in pTa urinary bladder cancer.

Construction of improved plasmid vectors for promoter characterization in Pseudomonas aeruginosa and other gram-negative bacteria.

We report the construction of two broad host range promoter-probe plasmid vectors for rapid analysis of promoters in Gram-negative bacteria. The new vectors, pME4507 and pME4510, carry carbenicillin and gentamycin resistance genes, respectively, and are small sized (4 kb) with a flexible multiple cloning site to facilitate directional cloning of putative promoter elements. The vectors allow rapid plate-based screening for promoter activities, using beta-galactosidase as the reporter enzyme. In the absence of an inserted promoter fragment, they display very low background activity, making them a useful tool for analysis of low expression level promoters.

Preoperative predictors of recurrent atrial fibrillation late after successful mitral valve reconstruction.

OBJECTIVE: Late outcome after mitral valve repair was examined to define preoperative predictors of recurrent atrial fibrillation late after successful mitral valve reconstruction. METHODS: One hundred and eighty-nine patients, 112 with preoperative sinus rhythm and 72 with preoperative chronic or intermittent atrial fibrillation, were followed for 12.2 +/- 10 years after valve repair. Clinic, hemodynamic end echocardiographic data were entered into Cox-regression and Kaplan-Meyer analysis to assess predictors for recurrent atrial fibrillation late after successful mitral valve repair. RESULTS: Univariate and multivariate predictors for recurrent atrial fibrillation late after successful mitral valve reconstruction were preoperative atrial fibrillation (P = 0.0001), preoperative antiarrhythmic drug treatment (P = 0.005), heart rate (P = 0.01), left ventricular ejection fraction (P = 0.01) and increased left ventricular posterior wall thickness (P = 0.05). Patients > 57.5 years with a mean pulmonary artery pressure > or =23 mm Hg and a history of preoperative antiarrhythmic drug treatment had an odds ratio of 53.33 (95% confidence limits 6.12-464.54) for atrial fibrillation late after successful mitral valve repair. CONCLUSION: Older patients with a history of atrial fibrillation, antiarrhythmic treatment or an elevated pulmonary artery pressure may present atrial fibrillation late after successful mitral valve repair. They could be considered for combined mitral valve reconstruction and surgery for atrial fibrillation even though sinus rhythm is present preoperatively.

[Anesthesia in laparoscopies: an overview]. / Anästhesie bei Laparoskopien: Eine Ubersicht.

In the last few years laparoscopic surgery requiring a different method of anesthesia from laparotomic procedures has been increasingly carried out. Since laparoscopic cholecystectomy was first described in 1985 almost all abdominal organs can now be operated on laparoscopically. At the same time the spectrum of the patients has changed from those who are young and healthy to older ones with many accompanying illnesses. In addition, the length of time this operations require has greatly increased. Consequently the number of critical incidents relevant to anaesthesia, during laparoscopy, has risen. Therefore new studies had been worked out which lead to a better understanding of pathophysiological changes during pneumoperitoneum.