Nonlinear selection and the evolution of variances and covariances for continuous characters in an anole.

The pattern of genetic variances and covariances among characters, summarized in the additive genetic variance-covariance matrix, G, determines how a population will respond to linear natural selection. However, G itself also evolves in response to selection. In particular, we expect that, over time, G will evolve correspondence with the pattern of multivariate nonlinear natural selection. In this study, we substitute the phenotypic variance-covariance matrix (P) for G to determine if the pattern of multivariate nonlinear selection in a natural population of Anolis cristatellus, an arboreal lizard from Puerto Rico, has influenced the evolution of genetic variances and covariances in this species. Although results varied among our estimates of P and fitness, and among our analytic techniques, we find significant evidence for congruence between nonlinear selection and P, suggesting that natural selection may have influenced the evolution of genetic constraint in this species.

Ampullary tumours (ampullomas) in the elderly--an interdisciplinary problem.

BACKGROUND & OBJECTIVES: Ampullary cancer is one of the periampullary tumours with better prognosis, but relapses occur early in some patients. This study was carried out to assess whether pancreatoduodenectomy (PDE, Whipple operation) could be a safe therapeutic procedure for elderly patients with periampullary tumours. METHODS: Between 2005 and 2007, 19 patients (12 male, 7 female) aged over 65 yr (range 66 and 83 yr) with diagnosis of ampulloma were operated. RESULTS: Of the 19 patients, 6 underwent local surgical ampullectomy with reinsertion of ductus choledochus and Wirsungi's duct for benign or early cancer lesion and 13 underwent PDE (Whipple operation). Of these 13, only one was in T1 stage, one was in T4 stage, two patients were T3 and the rest in T2 stage. Lesion of lymphatic system had 40 per cent of patients in T2 stage and all in T3 and T4 stages. One patient died of pulmonary embolism several days after operation. Post-operative complications occurred in 3 cases: 1 patient with partial dehiscence of gastroenteroanastomosis - treated by conservative approach, 2 patients with dehiscence of pancreatojejunoanastomosis. INTERPRETATION & CONCLUSIONS: Diagnosis and therapy of ampullary tumours is multimodal. With careful patient selection, PDE can be performed in elderly people (>65 yr) safely. The post-operative morbidity in this group is essentially influenced by their multi-morbidity.

[Pneumosurgery in the management of colorectal carcinomas]. / Pneumochirurgie v resení karcinomu kolorekta.

OBJECTIVE: Surgically solved lung involvement in patients after surgery of colorectal cancer. MATERIALS AND METHODS: Altogether 15 patients, 9 men (median age in the time of lung diagnosis 67 years) and 6 women (median age 59 years) underwent classical open pulmonary surgery during 2003-2008 years from the follow-up cohort of 836 persons after operation due to colorectal cancer in the time period of 1996-2008 years. The indication for lung surgery: solitary pulmonary lesion. Procedures distribution: pulmonary lobectomy 7, bilobectomy 2, segmentectomy 4, wedge resection 2. The requirement of the European Society of Thoracic Surgeons (ESTS) guidelines of complete pulmonary resection has been met by 10 operations (66.7%) with lobe specific lymphadenectomy. Histopathology investigation: Formalin fixed, paraffin embedded samples were investigated after hematoxylin-and-eosin staining, supplemented in case of need by immunohistochemistry of CK7, CK20 and TTF1. RESULTS: Eleven pulmonary metastases were found, in two cases with interlobar lymfatics involvement. Two metachronous primary adenocarcinomas of the lung (ADL) were diagnosed, one of them with metastases into hilar lymphatics. In remaining two patients pulmonary chondrohamartoma was discovered. CONCLUSION: Solitary pulmonary opacity in patient after colorectal surgery might not represent simple metastasis explicitly. Complete resection is needed.

[Complications in patients undergoing pulmonary oncological surgery]. / Komplikace u pacientu po operaci pro plicní malignitu.

AIM: A survey evaluating incidence and risk factors of complications in persons underwent complete open lung resection because of primary or secondary lung malignancy. MATERIAL AND METHODS: Retrospective study of 189 open surgery procedures in 128 males and 61 females, mean age males 61 years (range 21-78), females 64 years (range 33-80) during a five-years period (2003-2007). Data processing and analysis were performed with the statistical software system Statistica and compared by parametres odds ratio a chi2 test. RESULTS: Complications were divided into five groups. First group was defined as complications in perioperative period and was composed of three events 1.5%: endotracheal tube dysfunction (i.e. 0.5%), heavy cardiac arrhytmia 0.5% and serious haemorrhage, that occurred immediately after operation 0.5%. Second group includes complications within period of 7 days after surgery: prolonged air leak (PAL > 7 days) 7.4%, bronchopneumonia 6.9%, cardiac arrhythmia 6.9%, postoperative delirium 4.2%, atelectasis 2.6%, wound infection 1.1%, bleeding 1.1% and chylothorax 0.5%. Third group contains events between 8th and 30th postoperative days: thoracic empyema 2.1%, dysphonia 2.1%, painfull shoulder 1.1%, alimentary tract infection 0.5% and bronchial closure insufficiency 0.5%. Fourth group contains patients with severe complications, that led to death during 30 days after operation: ischemic stroke 0.5% and pulmonary embolism 0.5%. Patients without any complication formed the fifth group of 60.5%. CONCLUSION: Main risk factors for complications in postoperative period after lung resection due to primary or secondary lung malignancy in our group of patients are COPD, corticotherapy, time of operation over 3 hours, BMI over 25, left side tumor localization and bronchoplastic procedure. For cardiac arrhytmia seems to be risk factor pneumonectomy and previous neoadjuvant radiochemotherapy.

Relationship between volatile odorous substances and production of avermectins by Streptomyces avermitilis.

The time course of production of odorous compounds, i.e. geosmin and oxolones, and of avermectins was determined during the cultivation of S. avermitilis in flasks, 1- and 50-L fermentors. The amount of the antibiotics increased with increasing cultivation time up to more than 2 g/L while the concentration of geosmin rose to more than 4 mg/L. Cultivation without reflux condenser resulted in a lower product formation due to the higher stripping of geosmin. A relatively tight correlation was found between the production of geosmin and the production of avermectins. The production of oxolones peaked on cultivation days 3-5, the sum of oxolones being 60 microg/L. Subsequently, the production dropped below a measurable level. This can be explained as being due to the inhibition of oxolone production by geosmin.

Use of the industrial yeast Candida utilis for cadmium sorption.

The sorption ability of Candida utilis biomass for cadmium ions with accumulating competence of dried cells and cells in alginate was compared. After an optimization of process conditions (pH 5.5, biomass concentration 1 g/L and c0 50 mg/L), the cadmium sorption capacity of dried yeast biomass was perceptibly higher than that of the other tested adsorbents. Considering the sorption of the dried yeast biomass equal to 100 %, the cells in alginate reached 86 % while native cells showed only 42 %.

Removal of copper ions from dilute solutions by Streptomyces noursei mycelium. Comparison with yeast biomass.

Sorption properties of Streptomyces noursei mycelium for copper ions were compared with the accumulation competence of dried and native yeast (Candida utilis) biomass. The copper sorption capacity of S. noursei after optimization was found to be higher than that of the two other adsorbents (dried yeast biomass 82 %, native Candida cells 48 % of the sorption capacity of the S. noursei mycelium).

Continuous aerobic phenol degradation by defined mixed immobilized culture in packed bed reactors.

A defined mixed culture of Pseudomonas putida, Commamonas testosteroni and Candida tropicalis was immobilized by adsorption on polyurethane foam, cocoa-fibers, expanded slate and sintered glass. Packed bed reactors were used for long-term continuous phenol biodegradations. Loading experiments were done to study the impact of the following parameters: (1) hydraulic retention time, (2) dissolved oxygen concentration, and (3) elimination of the oxygen limitation. After the acclimation period (approximately 10 d), the loading test with the individual packings showed the following maximum degradation rates: sintered glass 34, polyurethane foam 12, expanded slate 11.5, and cocoa-fibers 7.7 kg m(-3) d(-1). All these values were reached at a removal efficiency >99 % and with oxygen in excess. Under these conditions, the pH of the diluted unbuffered medium in the reactor effluent was 3.2-4.0 and no incompletely oxidized metabolic intermediates were found. The free cell concentration in the effluent increased after the phenol overloading time period.

A new diagnostic approach to vascular rings and pulmonary slings: the role of MRI.

UNLABELLED: The conventional diagnostic work-up of a patient suspected of having a vascular cause for stridor, or dysphagia, includes esophagography and bronchoscopy to delineate the abnormal structure without imaging the structure itself. Cine-angiography is regarded as the golden standard, but is not routinely performed. Magnetic resonance imaging (MRI) is non-invasive and has the important advantage over cine-angiography of depicting all structures in the field of view. Color Doppler echocardiography depicts the great vessels, but not the esophagus and trachea. In 14 patients with obstructive symptoms and in four patients without obstructive symptoms MRI successfully imaged the abnormal structure, as was the case in two symptomatic patients using computer tomography. In this series, the findings were confirmed at surgery or by cine-angiography. CONCLUSION: we suggest that in patients suspected of having a vascular cause for stridor or dysphagia, MRI should be performed. If there is need for a screening procedure, color Doppler echocardiography should be used and if that is equivocal or non-conclusive, esophagography and bronchoscopy should be used. If MRI is difficult to interpret, it should be augmented by magnetic resonance angiography before considering cine-angiography.

Spin echo MRI in the evaluation of hearts with a double outlet right ventricle: usefulness and limitations.

The surgical approach to a double outlet right ventricle (DORV) is dependent on the spatial relationship of the semilunar valves, outflow tracts and ventricular septal defect (VSD). The purpose of the study was to assess the value of MRI for the evaluation of cardiovascular anatomy in patients before and after surgery for DORV. Spin echo MRI was performed in 12 patients with DORV (eight preoperative and four postoperative patients). Thin-section MRI was performed in three orthogonal planes and selected angulated views were obtained. Conventional imaging by color Doppler echocardiography and cine-angiocardiography and surgical findings, when present, served as the reference standards. The results found that the spatial relationship between semilunar valves and VSD was accurately assessed by MRI in eight out of eight preoperative patients. In the four postoperative cases MRI depicted the morphology of both outflow tracts and provided adequate information on their patency. Of the eight preoperative patients, five have undergone corrective surgery and the MRI findings were confirmed. MRI provided additional information to conventional imaging preoperatively in three cases in which the VSD opened into the outlet portion of the DORV, without there being a direct relation to a semilunar valve. In two preoperative cases in which the VSD was directly committed to the aorta, conventional imaging was conclusive. MRI was unable to depict aberrant chordae tendineae in four out of four cases. We conclude that MRI provides accurate additional anatomic information in patients with DORV, which is helpful in presurgical planning as well as during follow-up. Spin echo MRI does not visualize aberrant chordae tendineae.

Effects of vacuum compression therapy on skin microcirculation in patients suffering from lower limb ischaemia.

BACKGROUND: We investigated the short-term effect of vacuum compression (VC) treatment on skin microcirculatory perfusion in the foot of patients with lower limb ischaemia and healthy controls. PATIENTS AND METHODS: Ten patients with intermittent claudication or rest pain and 5 healthy controls underwent vacuum-compression treatment for half an hour. The leg was positioned in an air-tight plexiglass cylinder in which hypobaric (-115 mm Hg) and hyperbaric (75 mm Hg) pressure could be generated alternately, in order to improve peripheral circulation. The effect on skin microcirculation was investigated using nailfold capillary microscopy (measuring nutritive perfusion), laser Doppler fluxmetry (LDF) (total skin perfusion) and transcutaneous oxygen tension measurements (TcpO2). RESULTS: A few patients experienced ischaemic symptoms during VC, probably because the leg was pinched off through inflation of the cuff. In both patients and controls capillary microscopic parameters did not change significantly. In some cases, microcirculatory perfusion decreased because the leg had cooled during the treatment. Application of a heating matrass annihilated this effect. Only in the patient group a few LDF- and TcpO2 parameters improved slightly, but significantly. CONCLUSION: Vacuum-compression therapy only slightly improves total skin perfusion and oxygenation, but not the nutritive microcirculation, being an essential factor in the occurrence of ischaemic symptoms. We therefore conclude that this instrument in its present form is not an aid in the treatment of lower limb ischaemia.

Continuous growth of Candida utilis under periodic change of growth-limiting substrate.

A periodic change of limitation by glucose and ammonia was effected during continuous cultivation of Candida utilis. Values of feed parameters providing periodic nitrogen limitation were established. Cell biomass yield, macromolecular composition and parameters of individual cells (cell mass, budding percentage and cell-wall polysaccharide per surface square unit) were examined. The cyclic regime was found to result in culture synchrony. Parameters obtained on the basis of cell counts displayed a high sensitivity to changes in limitation where as the remaining parameters were less sensible.

The start-up period of styrene degrading biofilters.

Styrene vapors from contaminated air were eliminated using long-term adapted mixed microbial culture inoculated on four perlite packed biofilters (serial arrangement, up-flow configuration). During start-up the inlet concentration of styrene rose from 175 to 1300 mg/m3 of total carbon. The total actual residence time in the four biofilters was 24 s. Styrene was successfully degraded by the microbial population in the biofilter. An average of 66% of eliminated styrene was transformed to CO2. The removal efficiency of the pollutant was, after 18 d of start-up, nearly 85% at an organic load of 170 g/m3 per h. The concentration profiles along the bed height were linear for various pollutant inlet concentrations. The total amount of microorganisms in analyzed biomass from the biofilters was about 10(9) per gram of dry packing mass. The moisture content was around 80% in all biofilters.

Kinetics of phenol oxidation by Candida tropicalis: effects of oxygen supply rate and nutrients on phenol inhibition.

The kinetics of phenol degradation was estimated in a fed-batch reactor system. Effects of oxygen and nutrient excess or limitation as well as the presence of several essential ions on the phenol- and oxygen-specific uptake rates achieved simultaneously in a bioreactor were shown. Candida tropicalis was grown on phenol as the only carbon and energy source. Applying the best fit of polynomial function, the maximum specific uptake rates of phenol and oxygen, the critical concentrations of phenol, the half-saturation constants and inhibition constants were determined. Linear relationship between specific phenol uptake rate and the exogenous respiration rate was found regardless of the kind and presence of essential nutrients. At oxygen limitation both the phenol uptake rate and the cell affinity to phenol decreased more strongly compared with those under nutrient limitation. Oxygen in excess resulted in a significant increase of cell tolerance toward phenol. The presence of essential nutrients increased the specific phenol degradation rate and led to complete phenol oxidation.

Dependence of cell yield and specific growth rate of Candida boidinii on temperature during continuous cultivation.

Investigation of the dependence of cell yield of Candida boidinii in a chemostat and specific growth rate in a turbidostat on temperature was carried out using methanol as substrate. Each of the curves obtained had only one maximum, the optimum temperature for yield (Ys) and for specific growth rate (micron) being somewhat different. With deviation of temperature from the corresponding optimum the micron value decreases more sharply than that of Ys. The shape of two-factor dependences Ys(micron, T) and micron(S, T) is analyzed on the basis of these data and the known dependences of Ys on micron and micron on the limiting substrate concentration S. It is shown that the decelerating action of methanol on the growth rate increases at elevated and lower temperatures.

D-amino-acid oxidase--an improved production of the enzyme by the yeast Trigonopsis variabilis in a laboratory fermentor.

The cultivation of the yeast Trigonopsis variabilis producing D-amino-acid oxidase (an enzyme participating in the transformation of cephalosporin C into 7-aminocephalosporanic acid for the production of beta-lactam antibiotics) was controlled by changes of dissolved oxygen tension and extended fermentation times. The production technology was optimized on a laboratory scale and scale-up parameters were identified.

Physiological dendrogram of Claviceps spp. based on sucrose metabolism in submerged cultures and its comparison with phylogenetic tree.

Sixteen isolates of Claviceps spp. were analyzed for the production of polysaccharides, oligosaccharides, and sucrose metabolism under conditions of submerged fermentation. Physiological markers calculated by the Verhulst-Pearl law were used for hierarchical cluster analysis. Low correlation was found between physiologically based dendrogram and phylogenetic analysis constructed from an alignment of rDNA sequences. To confirm the intraspecific uniformity of physiological markers three isolates of C. africana from different hosts and locations were included. The influence of genotype, physiological variability, environmental location and habitat on metabolite production is discussed.

Effect of pH and loading manner on the start-up period of peat biofilter degrading xylene and toluene mixture.

Laboratory-scale biofilters packed with a mixture of peat, bark and wood were used for xylene and toluene removal from waste air. Two kinds of peat, which differed in the resulting pH of the leachate, were chosen for degradation of the pollutants by a mixed culture. Using peat with the lower pH value, the feasibility of single and multiple pollutant loading during the start-up period and augmentation with Pseudomonas putida strains were characterized. The lower pH value of the bed resulted in higher efficiency of toluene degradation from the mixture of pollutants. At higher pH values better degradation of both pollutants was achieved. Regarding the manner of loading during the start-up period, the best results were obtained using toluene as a single pollutant in the initial phase of operation. Pseudomonas strains demonstrated a high ability to degrade both pollutants; more efficient degradation for xylene than for toluene was observed at high loading rates.

Conidia production of Beauveria sp. by solid-state fermentation for biocontrol of Ilex paraguariensis caterpillars.

Conidia production of Beauveria sp. strain LAG by solid-state fermentation (SSF) using blends of agro-industrial residues (residual potatoes and sugar-cane bagasse) was optimized with respect to cultivation conditions and the composition of substrate mixture in Erlenmeyer flasks and column-type bioreactor. With a blend of 60 % residual potatoes and 40 % sugar-cane bagasse the optimum conditions achieved were: incubation temperature 26 degrees C, initial substrate pH 6, inoculum concentration 10(7) conidia per g substrate; optimal initial moisture of the substrate was 70 % for Erlenmeyer flasks, in column-type bioreactor (with forced aeration) the optimal initial moisture of the substrate was 65 % with airflow of 60 mL/min. The highest production (1.07 x 10(10) conidia per g dry substrate) was achieved after a 10-d fermentation. The conidia were used in laboratory assays against Thelosia camina and Hylesia sp., caterpillars that are serious pests of mate plants. The mortality of T. camina was >90 % 10 d after spraying caterpillars with 1 mL conidia suspension at a concentration 10(5)-10(8)/mL. For Hylesia sp., the mortality was 70 %, 7 d after immersion in the conidia suspension containing 108 conidia per mL. Therefore, the Beauveria sp. LAG can be considered to be an important biocontrol instrument in the prospect of the Integrated Pest Management for mate plants.