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13.

Purpose

To study the short- and long-term outcomes of kidney transplantation in patients with a bladder augmentation or urinary diversion compared to patients with a kidney transplantation in a normal functional bladder.

Patients and methods

Between January 2000 and March 2011, 13 patients received 16 grafts into a reconstructed urinary tract. We performed a retrospective case–control study and matched each patient to 4 controls for donor and recipient gender and year of transplantation.

Results

Short- and long-term complications of kidney transplantation occurred in 12 patients, varying from urinary tract infections to medical hospitalization with or without surgical or radiological intervention. In 5 patients, a percutaneous nephrostomy (PCN) was placed followed by surgical re-intervention. In three patients, the grafts failed as a result of chronic rejection and were re-transplanted. There was no graft loss as a result of surgical complications or the reconstructed urinary tract. One-year patient and graft survival was 100 %. After five years, all patients were alive and seven of nine grafts (77.8 %) were functioning. Mean follow-up time was 4.3 years. Among the controls, 55 grafts were transplanted in 52 patients. Ten patients received a PCN. Five patients needed surgical re-intervention. In three patients, transplantectomy was performed for ongoing rejection. Three patients were re-transplanted. One patient had a failing graft 7.5 years post-transplantation and became dialysis dependent.

Conclusion

Kidney transplantation in patients with a reconstructed urinary tract has an increased complication rate. Nevertheless, the long-term results are comparable to patients with a normal urinary bladder.  相似文献   
14.
Objective: Patients diagnosed with a psychotic disorder and their first-degree relatives display increased reactivity to stress. Theory predicts that experience of psychosocial stress is associated both with ventromedial prefrontal and mesolimbic dopamine neurotransmission. However, while there is evidence of aberrant striatal dopamine processing in psychotic disorder, the role of the prefrontal cortex remains under-researched. This study aimed at investigating stress-induced in vivo dopamine release in ventromedial prefrontal cortex (vmPFC) of individuals at familial risk for psychosis. Method: Fourteen healthy first-degree relatives of patients with a diagnosis of psychotic disorder and 10 control subjects underwent a single dynamic positron emission tomography (PET) scanning session after intravenous administration of 183.2 (SD = 7.6) MBq [18F]fallypride. Psychosocial stress was initiated at 100min postinjection using a computerized mental arithmetic task with social evaluative threat components. PET data were analyzed using the linearized simplified reference region model. Regression analyses were performed to compare the spatial extent of task-related ligand displacement between control subjects and relatives and to find how it related to self-rated experiences of psychosocial stress and psychosis. Results: First-degree relatives displayed hyporeactive dopamine signaling in the vmPFC in response to stress. Increased levels of subjectively rated stress were associated with increased intensity of psychotic experiences. This effect was particularly pronounced in first-degree relatives. Conclusion: Although previous studies have hypothesized a role for prefrontal dopamine dysfunction in psychosis, this study, to our knowledge, is the first in vivo human imaging study showing attenuated (ie, hyporeactive) dopamine stress neuromodulation in vmPFC of individuals at familial risk for psychosis.Key words: schizophrenia, positron emission tomography, neuromodulation, relatives, mesolimbic, salience  相似文献   
15.
It is shown that photo-CIDNP effects (CIDNP, chemically induced dynamic nuclear polarization) can be generated in the 360-MHz proton NMR spectrum of gene-5 protein from bacteriophage M13. This technique is used to determine the number of tyrosyl residues at the surface of the protein and to assign the resonances from the 3,5-ring protons of these residues. The DNA-binding site of the protein is investigated by formation of complexes with oligonucleotides. Complex formation leads to shifting and/or quenching of the photo-CIDNP emission signals of the surface tyrosines, implying that they are involved in DNA-protein interaction. These experiments are complemented by studying the complex formation of Lys-Tyr-Lys to poly(A).  相似文献   
16.
Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (Journal of Substance Use, 10, 191–197, 2005), including salience, mood modification, tolerance, withdrawal, conflict, and relapse. Two validated measures of Internet addiction were used (Compulsive Internet Use Scale [CIUS], Meerkerk et al. in Cyberpsychology & Behavior, 12(1), 1–6, 2009, and Assessment for Internet and Computer Game Addiction Scale [AICA-S], Wölfling et al. 2010) in two independent samples (ns?=?3,105 and 2,257). The fit of the model was analysed using Confirmatory Factor Analysis. Results indicate that the Internet addiction components model fits the data in both samples well. The two sample/two instrument approach provides converging evidence concerning the degree to which the components model can organize the self-reported behavioural components of Internet addiction. Recommendations for future research include a more detailed assessment of tolerance as addiction component.  相似文献   
17.
18.
The effect of cinnamaldehyde against biofilm cells of Salmonella Typhimurium ATCC 14028 was evaluated. We also assessed differential protein patterns that were expressed by biofilms compared with planktonic cells and protein expression by cinnamaldehyde-treated biofilms cells. This compound decreased biofilm biomass and metabolic activity of biofilms at both concentrations tested. Cinnamaldehyde treatment reduced the number of attached cells in polypropylene, reflected by colony count and scanning electron microscopy. The proteomic analysis of biofilms compared with planktonic cells indicated that several proteins were upregulated or downregulated, especially proteins that are involved in energy metabolism. Peroxiredoxin, ATP synthase alpha chain protein, conjugal transfer nickase/helicase TraI and elongation factor G were upregulated in untreated-biofilm cells, and their expression decreased as a function of cinnamaldehyde treatment. Cinnamaldehyde had antibiofilm activity, and several differentially expressed proteins identified provide potential and interesting targets to explore new control strategies for S. Typhimurium biofilms.  相似文献   
19.
Previously, it was shown that type IVB pili encoded by the Salmonella enterica serovar Typhi pil operon are used to facilitate bacterial entry into human intestinal epithelial cells in vitro and that such entry is inhibited by purified prepilin (pre-PilS) protein (X.-L. Zhang, I. S. M. Tsui, C. M. C. Yip, A. W. Y. Fung, D. K.-H. Wong, X. Dai, Y. Yang, J. Hackett, and C. Morris, Infect. Immun. 68:3067-3073, 2000). The pil operon concludes with a simple shufflon, and a recombinase gene product (Rci) inverts DNA in the C-terminal region of the pilV gene to allow synthesis of two distinct PilV proteins, PilV1 and PilV2, which are presumptive minor pilus proteins. We show here that the type IVB pili mediate bacterial self-association, but only when the PilV1 and PilV2 proteins are not expressed. This may be achieved in wild-type serovar Typhi by rapid DNA inversion activity of the shufflon. We show that the inversion activity inhibits the expression of genes inserted between the 19-bp inverted repeats used for Rci-mediated recombination and that the activity of Rci increases when DNA is supercoiled. The data suggest that serovar Typhi self-associates under conditions (such as low oxygen tension in the gut) that favor DNA supercoiling. These results explain (i) the function of the serovar Typhi shufflon and (ii) why there are only two possible shufflon states, in contrast to the many possible states of other shufflon systems. The data further indicate that a very early step in serovar Typhi pathogenesis may be type IVB pilus-mediated self-association of bacteria in the anaerobic human small intestine prior to invasion of the human gut epithelium. The suggested type IVB pilus-dependent step in typhoid fever pathogenesis may partially explain the enhanced invasiveness of serovar Typhi for humans.  相似文献   
20.

Background

Neurodevelopment outcomes of children conceived by Assisted Reproductive Technology (ART)have been the subject of much recent attention. To date there are no reports of neurodevelopmental performance before birth in this group.

Aims

To compare habituation (a measure of brain function) in fetuses conceived by assisted reproduction techniques (ART) with naturally conceived (NC) fetuses.

Study design

Case control study.

Subjects

Women with singleton pregnancies matched for maternal age, parity and smoking were recruited in 2 groups: ART (n = 20) and NC (n = 20).

Outcome measures

Sound stimuli (250 Hz, 110 dB) at 10 second intervals lasting 2 s were administered to the fetus. The end point was habituation (cessation of movement for five consecutive stimuli) or a maximum of 30 stimuli. Responses of the fetus were observed with ultrasound at 28, 32 and 36 weeks' gestation, video-recorded and anonymised for analysis.

Results

At 28 weeks' gestation significantly more ART fetuses responded to sound of 250 Hz, 110 dB (p = 0.02) but this difference did not persist at 32 and 36 weeks'. There was a significant increase in nonresponders as gestation advanced in the ART group. There was no difference in habituation or mean number of trials to habituate at all three gestations.

Conclusions

ART fetuses demonstrated no differences in habituation suggesting that there is no neurodevelopment delay. However, a decrease in response to sound as gestation advances might be a harbinger for poor perinatal outcomes and needs exploration.  相似文献   
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