Postoperative tracheal extubation after orthotopic liver transplantation

BACKGROUND

The duration of postoperative mechanical ventilation and its influence on pulmonary function in liver transplant recipients is still debated controversially.

METHODS

We retrospectively analyzed the incidence of immediate tracheal extubation, prolonged mechanical ventilation (>24 h following surgery), and episodes of reintubation in 546 patients who underwent orthotopic liver transplantation (OLT) at our institution.

RESULTS

Immediate tracheal extubation in the operating theater was achieved in 18.7% of patients, and prolonged mechanical ventilation was required by 11.2% of patients. In these, median time of extubation was 49.5 h, whereas the remaining 70.1% of patients required ventilation support for a median 5 h after OLT. As risk factors for prolonged mechanical ventilation we identified the indications of acute liver failure and retransplantation, as well as factors such as mechanical ventilation prior to OLT, massive intraoperative bleeding, and severe reperfusion injury of the liver graft. The incidence of reintubation was 8.8% in patients who were immediately extubated following surgery, and 13.1% in patients who underwent extubation within 24 h. The incidence was significantly increased in patients requiring prolonged mechanical ventilation (36.1%).

CONCLUSIONS

Immediate tracheal extubation was safe and well tolerated. The incidence of reintubation was not increased when compared to patients in whom extubation succeeded later. However, special attention should be given to transplant recipients presenting in reduced clinical condition at the time of OLT, undergoing complicated surgery, or receiving liver allografts with severe reperfusion injury because of an increased risk for prolonged mechanical ventilation.

The adsorption kinetics of metal ions onto different microalgae and siliceous earth

In the present work the adsorption kinetics of the six metal ions aluminum, zinc, mercury, lead, copper, and cadmium onto living microalgae were measured. The freshwater green microalga Scenedesmus subspicatus, the brackish water diatom Cyclotella cryptica, the seawater diatom Phaeodactylum tricornutum, and the seawater red alga Porphyridium purpureum were the subject of investigation. In most cases the adsorption rate of the metals could be well described by using the equation of the Langmuir adsorption rate expression. Inverse parameter estimation allowed the determination of the rate constants of the adsorption process and the maximum metal content of the algae. The highest values for the rate constant were obtained for Porphyridium purpureum followed by Phaeodactylum tricornutum. High values for the maximum content were obtained for Cyclotella cryptica and Scenedesmus subspicatus. The maximum rate constant was 24.21 h-1 for the adsorption of Hg to Porphyridium purpureum whereas the maximum metal content (0.243 g g-1) was obtained for Zn on Cyclotella cryptica. A comparison of these values with those obtained for the mineral siliceous earth exhibiting low maximum content and high adsorption rates reveals that the mechanism of adsorption onto the algae is a mixture of adsorption and accumulation.

Lithuanian haemophilia A and B registry comprising phenotypic and genotypic data

Haemophilia represents the most common hereditary severe bleeding disorder in humans. About 100 families with this condition live in Lithuania, one of the Baltic states with a population of 3.7 million. Haemophilia care and genetic counselling are still rendered difficult owing to limited availability of clotting factor concentrate and molecular genetic diagnosis. In the present study, a haemophilia registry, comprising phenotypic and genotypic data of the majority of Lithuanian haemophilia A and B patients, was established. The phenotype includes the degree of severity, factor VIII:C, factor VIII:Ag, factor IX:C, von Willebrand factor and antigen (VWF:RiCoF, vWF:Ag) and inhibitor status. Genotyping of the factor VIII and IX genes was performed using mutation screening methods and direct sequencing. In 61 out of 63 patients with haemophilia A (96.8%) and all eight patients with haemophilia B (100%), the causative mutations could be detected. Nineteen of the factor VIII gene defects and two of the factor IX gene mutations are reported for the first time. Identified mutations allowed direct carrier diagnosis in 83 female relatives revealing 44 carriers, 38 non-carriers and one somatic mosaicism. The information provided by this registry will be helpful for monitoring the treatment of Lithuanian haemophilia patients and also for reliable genetic counselling of the affected families in the future.

The role of psychosocial factors in fibromyalgia syndrome

OBJECTIVE

The main objective of this review was to evaluate the role of psychosocial factors in the development of fibromyalgia syndrome.

METHOD

Review of the literature concerning the influence of psychosocial factors.

RESULTS

In fibromyalgia syndrome psychosocial factors are relevant at different etiological levels. They can be classified into predisposing, triggering and stabilising/"chronifying" factors.

CONCLUSION

Due to the increasing knowledge about the influence of psychosocial factors for the development of fibromyalgia, the biomedical model has to be expanded to a biopsychosocial model. The biopsychosocial concept has an impact on the therapeutic approach. Strong evidence for the model is provided by the good results of interdisciplinary treatment studies.

Elevated interleukin-4 and interleukin-13 production by T cell lines from patients with Churg-Strauss syndrome

OBJECTIVE

To investigate cytokine production patterns of T cell lines (TCL) from patients with Churg-Strauss syndrome (CSS).

METHODS

Short-term polyclonal TCL were generated from peripheral blood of patients with CSS or Wegener's granulomatosis (WG) and healthy controls (HC). TCL were established in the presence of interleukin-2 (IL-2) and phytohemagglutinin and were phenotypically characterized by flow cytometry. Th1/ Th2 cytokine production by stimulated TCL (72 hours) was analyzed by enzyme-linked immunosorbent assay.

RESULTS

TCL that represented the progeny of in vivo-activated T cells from CSS patients displayed a heterogeneous immunophenotype, with a predominance of CD4+ T cells when compared with WG TCL, which were predominantly CD8+. All CSS TCL shared the ability to produce large amounts of interferon-gamma (IFNgamma), IL-4, and IL-13 compared with HC (P = 0.014 for all 3). Production of IL-4 and IL-13 was higher in CSS TCL than in WG TCL (P = 0.014 for both). IL-5 production was up-regulated in WG TCL compared with CSS TCL (P = 0.014). Compared with HC, WG TCL showed increased production of IFNgamma (P = 0.021), IL-5 (P = 0.043), and IL-13 (P = 0.021).

CONCLUSION

Our results indicate that, while there is evidence for both a type 1 and a type 2 response in CSS, type 2 cytokine production pattern appears to predominate in this disease when compared with WG and HC.

Developmental and cellular expression pattern of epithelial sodium channel alpha, beta and gamma subunits in the inner ear of the rat

Endolymphatic ion composition in the adult inner ear is characterized by high K(+) and low Na(+) concentration. This unique ion composition is essential for proper functioning of sensory processing. Although a lot has been learned in recent years about molecules involved in K(+) transport in inner ear, the molecules involved in Na(+) transport are only beginning to emerge. The epithelial Na(+) channel (ENaC) is a highly selective Na(+) channel that is expressed in many Na(+)-reabsorbing tissues. The aim of our study was to investigate whether ENaC is expressed in inner ear of rats and could account for Na(+) reabsorption from endolymph. We detected mRNA for the three channel-forming subunits (alpha, beta and gamma ENaC) in cochlea, vestibular system and endolymphatic sac. mRNA abundance increased during the first 12 days of life in cochlea and vestibular system, coinciding with decreasing Na(+) concentration in endolymph. Expression was strongest in epithelial cells lining scala media, most notably Claudius' cells. As these cells are characterized by a very negative resting potential they would be ideally suited for reabsorption of Na(+). mRNA abundance in endolymphatic sac decreased during the first 6 days of life, suggesting that ENaC might be implicated in reabsorption of endolymph in the endolymphatic sac of neonatal animals. Together, our results suggest that the epithelial Na+ channel is a good candidate for a molecule involved in Na(+) homeostasis in inner ear.

Risk factors for severe hemorrhagic transformation in ischemic stroke patients treated with recombinant tissue plasminogen activator: a secondary analysis of the European-Australasian Acute Stroke Study (ECASS II)

BACKGROUND AND PURPOSE

Intravenous thrombolysis with recombinant tissue plasminogen activator (rtPA) improves the outcome for ischemic stroke patients who can be treated within 3 hours of symptom onset. The efficacy of thrombolysis has been demonstrated despite an increased risk of severe hemorrhagic transformation (HT) in patients treated with rtPA. We performed an analysis of risk factors for severe HT in the second European-Australasian Acute Stroke Study (ECASS II).

METHODS

HTs were classified by using clinical and radiological criteria as follows: hemorrhagic infarction (HI), parenchymal hemorrhage (PH), and symptomatic intracranial hemorrhage (SICH). Potential risk factors for HT were tested by stepwise logistic regression analysis, including rtPA-by-variable interactions. In addition, the distribution of bad outcome (modified Rankin score 5 to 6) at day 90 was stratified according to each category of HT.

RESULTS

PH and SICH but not HI were associated with rtPA. Also, PH and SICH but not HI were more severe in rtPA-treated patients than in those receiving placebo. Risk factors for PH were rtPA, extent of parenchymal hypoattenuation on baseline CT, congestive heart failure, increasing age, and baseline systolic blood pressure. The risk of PH on rtPA was increased in older patients and in those who were treated with aspirin before thrombolysis. Risk factors for SICH were rtPA, congestive heart failure, extent of parenchymal hypoattenuation, and increasing age. The risk of SICH on rtPA was increased in patients who were treated with aspirin before thrombolysis.

CONCLUSIONS

This secondary analysis of ECASS II has confirmed the importance of the extent of hypoattenuation as a risk factor for severe HT. The findings also suggest that older patients and those who have used aspirin before stroke are at higher risk of a severe HT on rtPA.

Homocysteine, its metabolites, and B-group vitamins in renal transplant patients

BACKGROUND

Increased plasma total homocysteine (tHcy) levels are an independent risk factor for cardiovascular morbidity in patients with normal and impaired renal function, including stable renal transplant recipients (RTRs). Plasma concentrations of the metabolites of Hcy, such as cystathionine (Cys), methylmalonic acid (MMA), 2-methylcitric acid (MC), and its diastereomers MCI and MCII have been reported in only a few articles. We therefore looked for the serum concentration of these metabolites and their relationship to renal function, cardiovascular diseases, the immunosuppressive treatment, and serum concentrations of cobalamin and folate.

METHODS

Fifty RTRs (mean age 50.4 +/- 11.8 years, 35.9 +/- 44.4 months after kidney transplantation) and 35 controls (NP; mean age 43.5 +/- 14.4 years) were studied. Total Hcy and its metabolites were measured by gas chromatography-mass spectrometry (GC-MS).

RESULTS

Total Hcy, MMA, Cys, and MC were elevated twofold to sixfold as compared with NP, with a significant interrelationship between these compounds. With the exception of Cys, they were significantly correlated with serum creatinine. Serum folate levels were inversely correlated with tHcy, Cys and cobalamin with MMA and the ratio of MCI/MCII. There was no correlation between tHcy concentration and its metabolites with immunosuppressive treatment (CsA vs. FK506), clinical history, or current findings of cardiovascular complications and blood pressure profile.

CONCLUSION

Prospective studies are needed to find out whether the lowering or normalization of serum concentrations of tHcy and its metabolites due to treatment with B vitamins should be achieved to reduce the cardiovascular risk and improve the long-term outcome of allografts and of patients.

Deep-core dielectronic-capture resonances in the electron-impact ionization of heavy atomic ions

Experimental measurements and theoretical calculations are carried out for the electron-impact ionization of Sm(12+). The low energy region of the single ionization cross section for Sm(12+) is found to be dominated by contributions from the indirect process of excitation autoionization. At about 1.0 keV strong resonance features are found in the experimental crossed-beam measurements performed in scan mode at high resolution. Theoretical calculations confirm that the high energy experimental features are due to deep-core dielectronic capture followed by sequential double Auger decay. The discovery of these unusual high energy resonances in single and multiple ionization opens the door for future systematic studies of how heavy atomic ions with deep inner-shell vacancies achieve final stabilization.

Assessment of toxicity and mutagenicity in air particulate matter from an urban industrial area in the coast of the Rio de la Plata

Chemical characterization and effects assessment of semivolatile organic compounds in organic extracts from air particulate matter from the region of the greater La Plata area was undertaken. Effects covered the study of mutagenicity with the Ames test (Salmonella typhimurium TA100 and TA98 strains with metabolic activation by S9) and cytotoxicity using the Tetrahymena pyriformis test system (growth rate, cell volume, and cell respiration). Chemical analysis of organic extracts was done using gas chromatography. Results demonstrate the presence of polycyclic aromatic hydrocarbons (PAH) in the matrix, high mutagenicity, and cytotoxicity. A higher mutagenic activity detected with TA98 and TA100 strains is associated with an increment of total PAH and total five or six ring PAH content, respectively. Linked with it, a PAH dependent toxicity on Tetrahymena pyriformis has been observed. This cell system proved to be very sensitive. From the results obtained with the cell respiration assay with T. pyriformis it appears that uncoupling agents are present in the samples. The results of this study indicate that air particulate matter from the Rio de La Plata area contains significant genotoxic and cytotoxic activity probably due to the presence of PAHs.

[Ultrasound diagnosis of Meckel diverticulitis in adults]

Meckel's diverticulitis is a rare disease. In addition to physical examination, abdominal ultrasound can help to pinpoint the diagnosis. By presenting a case report we would like to demonstrate the typical ultrasonographic findings in acute Meckel's diverticulitis and differentiate it from acute appendicitis. A 60-year-old patient was admitted to our hospital with the diagnosis of acute appendicitis. Abdominal ultrasound was performed and a blind ending, liquid-filled segment of small bowel in the right lower quadrant of the abdomen found. This segment was not compressible, no peristalsis was evident, nor was there any anatomical association with the cecum. Locally we found free fluid and hints of inflamed mesenteric fatty tissue. A perforated Meckel's diverticulum was diagnosed and confirmed intraoperatively. The major ultrasonographic difference between an inflamed Meckel's diverticulum and acute appendicitis is its anatomical location. In contrast to the appendix there is no association with the cecum. A diameter of up to 40 mm and a well-defined wall of small bowel with 3 definite layers visible by ultrasound may help to distinguish between a Meckel's diverticulum and the appendix.

Mechanical disintegration of sewage sludge

Mechanical disintegration can be used for an accelerated and improved anaerobic digestion of excess sludge. The hydrolysis is the limiting step of this process. Mechanical disintegration can be used to disrupt the cell walls and to cause the release of the organic material from the cells. Particle size analysis describes the size reduction but is not suitable for characterising the release of the organic material and the cell disruption. Two biochemical methods were developed for these phenomena. One of the parameters provides information about the disruption of micro-organisms, the other one gives information about the release of organic material. Different ultrasonic homogenizers, a high pressure homogenizer and stirred ball mills were used for disintegration experiments using various parameters. The influences of a mechanical disintegration on the particle size and of the energy intensity on the disintegration were investigated. Further investigations had to detect the influence of the solid content on the disintegration results. For sludge with a higher solid content better results in terms of energy consumption could be achieved. An optimum of the bead diameter and the stress intensity in stirred ball mills could be detected. A comparison of the results of different methods of sludge disintegration shows that the investigated ultrasonic homogenizers are inferior to a high pressure homogenizer and a stirred ball mill in terms of energy consumption.

Synthetic HLA-A2 derived peptides are recognized and presented in renal graft recipients

Indirect presentation of allogeneic MHC antigen is an important pathway by which allografts are rejected and tolerance maintained by regulatory CD4(+) T cells. In this study HLA-A2 derived synthetic peptides were used to determine whether T cells of non-HLA-A2 renal graft recipients, which had been HLA-A2 mismatched to their organ donors, recognize some of the HLA-A2-derived peptides. Among the HLA-A2 mismatched patients, 60% recognized residues 56--69, 65--79, and 75--89. Peripheral blood lymphocytes derived from healthy individuals showed low reactivity towards allopeptides, indicating that sensitization towards HLA-A2 induced response towards HLA-A2 derived peptides. The response to the peptides was blocked by antibodies to HLA-DR, -DQ, and CD4. Depletion of antigen presenting cells abrogated response towards the allopeptides, confirming that the observed proliferation was mediated by the indirect pathway. Interestingly, although none of the HLA-A2 mismatched patients had any signs for either acute or chronic rejection, considerable response to allo-derived HLA-A2 was observed.

Role of homocysteine, cystathionine and methylmalonic acid measurement for diagnosis of vitamin deficiency in high-aged subjects

BACKGROUND

Intracellular B-vitamin and folate deficiency indicated by hyperhomocysteinemia is very frequent in the elderly population. Hyperhomocysteinemia increases the risk of atherothrombotic diseases and neuropsychiatric complications. Our aim was to evaluate the prevalence of increased serum metabolite concentrations in subjects of a higher age, and whether the measurement of metabolite concentrations is more effective in diagnosing B-vitamin deficiency than mere homocysteine.

MATERIALS AND METHODS

Homocysteine (HCY), cystathionine (CYS) and methylmalonic acid (MMA) were investigated in serum together with vitamin B-12, B-6 and folate in 90 high-aged subjects (85-102 years), 92 seniors (65-75 years), and in 50 younger subjects (19-50 years).

RESULTS

Elderly subjects (high-aged and senior) had elevated serum concentrations of metabolites. High-aged subjects had a higher frequency of pathological increases than seniors: HCY 62% vs. 24%; MMA 62% vs. 23%; CYS 81% vs. 36%. Folate and vitamin B-6 concentrations were significantly decreased in both elderly groups; vitamin B-12 was only decreased in high-aged subjects. Utilising vitamin B-6, B-12 and folate for diagnosis of intracellular vitamin deficiency, the rate was 30% in seniors and 55% in high aged subjects. However, utilising the metabolites (HCY, MMA and CYS) for the diagnosis of intracellular vitamin deficiency, there was a distinctly increased rate of 55% in seniors respective to 90% in high-aged subjects. Backward multiple regression analysis revealed that only folate, MMA, creatinine and age were independent variables influencing the HCY concentration. Furthermore, the MMA concentration was significantly and independently influenced by folate, vitamin B-12, HCY and creatinine, and the serum concentration of CYS by vitamin B-12, creatinine and age.

CONCLUSION

The metabolites HCY, MMA and CYS are sensitive indicators diagnosing impaired remethylation of homocysteine to methionine with parallel activation of catabolic pathway. Compared to mere HCY or B-vitamins in serum, the efficiency of diagnosing a disturbed HCY metabolism increases very much in utilising the metabolites HCY, MMA and CYS. For differential diagnosis, parallel measurement of folate and creatinine is recommended. The early and correct diagnosis of B-vitamin deficiency in elderly subjects is of high clinical relevance.

Effect of chronic angiotensin II inhibition on the cardiovascular system of the normal rat

Previous studies have demonstrated in normal rats that chronic treatment, from weaning to 30 days, with either enalapril or losartan, induced significant changes in cardiovascular structure and function. The present study was performed to assess the effect of either enalapril or losartan on the structure and function of the heart and arteries given to normal rats from weaning until 6 months of age. Animals (n = 48) were divided into three groups: control, enalapril treated, and losartan treated; treated rats received 10 mg/kg/day of drug. Blood pressure, body weight, and water intake were recorded for that time period. DNA, cGMP, collagen, degree of fibrosis, and nitric oxide synthase-NADPH-diaphorase-dependent activity in the heart and arteries were determined. Only significant differences (P < .05) are reported. Blood pressure increased only in control rats (13 +/- 1 mm Hg), enalapril treatment enhanced water intake and reduced the rate of body growth (control, 672.9 +/- 15.4 g; losartan, 692.4 +/- 21.8 g; enalapril, 541.8 +/- 13.8 g). In the heart, DNA (control, 120 +/- 5; losartan, 99 +/- 4; enalapril, 93 +/- 6 microg/100 mg), collagen (control, 2.5 +/- 0.2; enalapril, 1.85 +/- 0.08 microg/100 mg), and fibrosis (control, 3.5 +/- 0.4%; losartan, 2.2 +/- 0.3%; enalapril, 2.1 +/- 0.4%) were reduced by treatment. In the aorta, cGMP (control, 0.15 +/- 0.01; losartan, 0.24 +/- 0.02 pmol/mg), and NADPH-diaphorase (control, 0.114 +/- 0.003; losartan, 0.148 +/- 0.006; enalapril, 0.169 +/- 0.003 as optical density) were enhanced. The enzyme was also higher in the aortic endothelium of treated animals (control, 0.193 +/- 0.010; losartan, 0.228 +/- 0.009; enalapril, 0.278 +/- 0.005). The lower rate of body weight increase, the enhanced water intake, and the reduced cardiac and left ventricular weight attributable to enalapril treatment do not seem to be related to inhibition of the renin-angiotensin system. On the other hand, renin-angiotensin system inhibition induces a protective effect on the heart and aorta through structural and functional changes. Most of this action seems to be exerted through angiotensin II type 1 receptors.

Characterization of SepL of enterohemorrhagic Escherichia coli

The sepL gene is expressed in the locus of enterocyte effacement and therefore is most likely implicated in the attaching and effacing process, as are the products encoded by open reading frames located up- and downstream of this gene. In this study, the sepL gene of the enterohemorrhagic Escherichia coli (EHEC) strain EDL933 was analyzed and the corresponding polypeptide was characterized. We found that sepL is transcribed monocistronically and independently from the esp operon located downstream, which codes for the secreted proteins EspA, -D, and -B. Primer extension analysis allowed us to identify a single start of transcription 83 bp upstream of the sepL start codon. The analysis of the upstream regions led to the identification of canonical promoter sequences between positions -5 and -36. Translational fusions using lacZ as a reporter gene demonstrated that sepL is activated in the exponential growth phase by stimuli that are characteristic for the intestinal niche, e.g., a temperature of 37 degrees C, a nutrient-rich environment, high osmolarity, and the presence of Mn(2+). Protein localization studies showed that SepL was present in the cytoplasm and associated with the bacterial membrane fraction. To analyze the functional role of the SepL protein during infection of eukaryotic cells, an in-frame deletion mutant was generated. This sepL mutant was strongly impaired in its ability to attach to HeLa cells and induce a local accumulation of actin. These defects were partially restored by providing the sepL gene in trans. The EDL933DeltasepL mutant also exhibited an impaired secretion but not biosynthesis of Esp proteins, which was fully complemented by providing sepL in trans. These results demonstrate the crucial role played by SepL in the biological cycle of EHEC.

Indolic constituents and indole-3-acetic acid biosynthesis in the wild-type and a tryptophan auxotroph mutant of Arabidopsis thaliana

The tryptophan auxotroph mutant trp3-1 of Arabidopsis thaliana (L.) Heynh., despite having reduced levels of L-tryptophan, accumulates the tryptophan-derived glucosinolate, glucobrassicin and, thus, does not appear to be tryptophan-limited. However, due to the block in tryptophan synthase, the mutant hyperaccumulates the precursor indole-3-glycerophosphate (up to 10 mg per g FW). Instability of indole-3-glycerophosphate leads to release of indole-3-acetic acid (IAA) from this metabolite during standard workup of samples for determination of conjugated IAA. The apparent increase in "conjugated IAA" in trp3-1 mutant plants can be traced back entirely to indole-3-glycerophosphate degradation. Thus, the levels of neither free IAA nor conjugated IAA increase detectably in the trp3-1 mutant compared to wild-type plants. Precursor-feeding experiments to shoots of sterile-grown wild-type plants using [2H]5-L-tryptophan have shown incorporation of label from this precursor into indole-3-acetonitrile and indole-3-acetic acid with very little isotope dilution. It is concluded that Arabidopsis thaliana shoots synthesize IAA from L-tryptophan and that the non-tryptophan pathway is probably an artifact.