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Ultraviolet damages sperm mitochondrial function and membrane integrity in the sea urchin Anthocidaris crassispina.

Effects of ultraviolet A (UVA) and ultraviolet B (UVB) on mitochondrial function and membrane integrity of sea urchin sperm were investigated using flow cytometry and fluorescent probes. Both UVA and UVB impaired sperm mitochondrial function in a dose-dependent manner. Covariance analysis further showed that the slopes of change in mitochondrial function in relation to UVA and UVB were significantly different, suggesting that the modes of action were different. UVA did not affect membrane integrity, while membrane integrity showed a linear reduction with increasing UVB doses. Sperm mitochondria function showed significant positive correlations with sperm motility and subsequent fertilization success. Overall, our results showed that both UVA and UVB could decrease sperm motility and fertilization success through impairment of mitochondrial function, whereas UVB alone could cause additional damage through impairing the functional integrity of sperm membrane. Mitochondrial function of sperm may also offer a reliable ecotoxicological biomarker for predicting fertilization success in urchins.

Animals↗

Strategies for successful clinical information system selection.

The CIS market is volatile. With consumer pressure to develop and the current interest in CISs, clinicians recommended reassessing the market again in 18 months. Even without fully mature systems, there are foundational CISs available on the market. Strategies for successful CIS selections are many: Decide to be a developer or buyer early in the process. Entering into a long-term relationship with a vendor to develop customized capabilities will mandate different requirements than purchasing a ready-to-use system. Use a systematic method for evaluating systems, preferably multimethod. Force structure into the evaluation process with vendors, especially for the system demonstration. Structure will ensure that each system function, or lack of function, is exposed and assessed and will allow for consistent and fair evaluations across vendors. Make the vendor commit to distinguishing between existing and proposed functions during system demonstrations. Often, vendors promise the very functions you want to be in the next release. Most vendors will cooperate with structured schedules. However, some vendors may resist structure because it interferes with marketing strategies. If, despite requests for specific materials and schedules, vendors fill the time with unsolicited material, ask yourself why and beware: they may not have the functions you requested. Use a brief clinical scenario as a preview into system functions, integration, and system usability. Ask vendors for conceptual models of system functional and technical architecture. Use an interdisciplinary team. Focus subgroups in specialty areas for efficiency and effectiveness in evaluation. Consider tape-recording the joint group sessions for later confirmation or analysis. Consider application integration as one of the major requirements for future CISs, especially between ambulatory and inpatient arenas.

Decision Making, Organizational↗

Stem cell therapy for ischemic heart disease.

Recent experimental and clinical observations have suggested that cell transplantation could be of therapeutic value for the treatment of heart disease. This approach was based on the idea that transplanted donor cardiomyocytes would integrate with the host myocardium and thereby directly contribute to cardiac function. Surprisingly, the observation that non-cardiomyogenic cells could also improve cardiac function indicates that functional integration of donor cells might not be required to achieve a beneficial effect. More recently, several observations have suggested the presence of a greater than anticipated developmental repertoire in adult-derived stem cells, which, if further validated, would offer unprecedented opportunities for the restoration of cardiac function in diseased hearts. Here, we discuss current issues regarding the potential use of stem cell transplantation for the treatment of ischemic heart disease.

Animals↗

Integrating knowledge based functionality in commercial hospital information systems.

Successful integration of knowledge-based functions in the electronic patient record depends on direct and context-sensitive accessibility and availability to clinicians and must suit their workflow. In this paper we describe an exemplary integration of an existing standalone scoring system for acute abdominal pain into two different commercial hospital information systems using Java/Corba technolgy.

Abdomen, Acute↗

Biocompatibility studies with bicarbonate-based solutions.

During long-term peritoneal dialysis (PD) treatment, the biocompatibility of the dialysis fluid is one of the factors that determine the functional integrity of the peritoneal mesothelium and stroma, and the alertness and functional capacity of the peritoneal host defense system. In vitro studies show that conventional acidic lactate-based PD solutions (LB fluids) are detrimental to some of the more important functions of the peritoneal cell system including mesothelial and white blood cells. The main toxic components of the fluids are the high hydrogen ion content (pH = 5-5.6), high lactate concentration, and osmolality. Some toxic side effects can be omitted using bicarbonate-based fluids (BB fluids), in which lactate has been replaced by bicarbonate and the pH has been normalized (7.2-7.4). The present paper is an overview of the biocompatibility tests and studies performed using bicarbonate-based continuous ambulatory peritoneal dialysis (CAPD) fluids. While the final long-term clinical evaluation of the BB fluids is still missing, biocompatibility tests indicate that these fluids are less toxic to many cell systems than the conventional acidic LB fluids. BB fluids with a high glucose content remain cytotoxic. The BB fluids are well tolerated in animal studies. Some BB fluids increase the ultrafiltration in short-term animal studies when compared with LB fluids. The few animal studies failed to demonstrate a better preservation of the peritoneal membrane integrity by BB fluids. The difference in cell toxicity between LB and BB fluids as measured in vitro also seems detectable during the first 30 min of intraperitoneal dwell in man.

Animals↗

Thrombolysis for experimental deep venous thrombosis maintains valvular competence and vasoreactivity.

PURPOSE: Thrombolysis protects the structural and functional integrity of vein wall in an experimental model of acute deep venous thrombosis (DVT) immediately after treatment, but late sequelae have not been studied. We designed experiments to compare the effects of thrombolysis and surgical thrombectomy at 4 weeks after the treatment of DVT. METHODS: DVT was produced bilaterally in male mongrel dogs by proximal and distal femoral vein ligation. Five dogs underwent sham operation. After 48 hours, the ligatures were removed, and the thrombosis was treated with either Fogarty balloon catheter thrombectomy (shear force, 60 g; n = 6) or catheter-directed urokinase infusion (4000 U/min for 90 minutes; n = 6). At 4 weeks, patency and valvular competence were determined by duplex ultrasound scanning. Thrombogenicity was studied by the measurement of radiolabeled fibrin and platelet deposition. Veins were explanted and prepared for histologic examination, scanning electron microscopy, and functional studies in organ chambers. RESULTS: All veins were patent at 1 month. Recanalized thrombus was observed histologically in four (66%) thrombectomized veins, one (17%) thrombolyzed vein, and none of the sham-operated veins (P =.04). Scanning electron microscopy demonstrated similar luminal endothelial cell loss (11%-25%) in all three groups. Platelet and fibrin depositions were not different among groups. Valvular incompetence (reflux duration, >0.5 sec) did not differ significantly in the groups (thrombectomized veins, 2 of 12 (17%); thrombolyzed veins, 0 of 12 (0%); P = NS). In organ chamber studies, endothelium-dependent relaxations to calcium ionophore, but not adenosine diphosphate, were inhibited by an antagonist of nitric oxide production after thrombectomy (P <.05, thrombectomy vs sham- and thrombolysis-treated veins). All veins relaxed to exogenous nitric oxide. CONCLUSION: Both thrombectomy and thrombolysis restored patency and achieved similar valvular competence. Surgical thrombectomy, however, resulted in more residual thrombus and contributed to changes in endothelium-mediated relaxations at 4 weeks. Thrombolysis maintained both structural integrity and endothelial function.

Adenosine Diphosphate↗

Infliximab may reverse the toxic effects induced by tumor necrosis factor alpha in human spermatozoa: an in vitro model.

OBJECTIVE: To examine the toxic effects of tumor necrosis factor alpha (TNF-alpha) on ejaculated spermatozoa and evaluate the ability of infliximab to reverse these effects. DESIGN: Prospective controlled study. SETTING: Cleveland Clinic Foundation, Cleveland, Ohio. PATIENT(S): Thirty-one healthy sperm donors. INTERVENTION(S): Exposure of human spermatozoa to varying concentrations of TNF-alpha (100, 300, 400, 500 pg/mL, and 2.5 microg/mL) and infliximab (400 microg/mL). MAIN OUTCOME MEASURE(S): Sperm motility, functional integrity of plasma membrane, and DNA fragmentation. RESULT(S): Spermatozoa quality declined following incubation with TNF-alpha in a dose-dependent and time-dependent manner. Sperm motility and membrane integrity were higher in the samples incubated with TNF-alpha plus infliximab than in the samples treated with TNF-alpha only. These parameters improved significantly and were comparable with both controls and sperm incubated with infliximab alone. Similarly, the percentage of spermatozoa with DNA fragmentation improved significantly following incubation with TNF-alpha plus infliximab and again was comparable with both controls and sperm incubated with infliximab alone. CONCLUSION(S): Spermatozoa may be exposed to abnormal levels of TNF-alpha in the male reproductive tract or during their passage into the female reproductive tract (in cases of endometriosis). Exposing spermatozoa to pathological concentrations of TNF-alpha can result in significant loss of their functional and genomic integrity. Infliximab could potentially be used to help treat female infertility caused by endometriosis in those with elevated levels of TNF-alpha in their peritoneal fluid.

Analysis of Variance↗

Fractal analysis of striatal dopamine re-uptake sites.

Spatial variation in regional blood flow, metabolism and receptor density within the brain and in other organs is measurable even with a low spatial resolution technique such as emission tomography. It has been previously shown that the observed variance increases with increasing number of subregions in the organ/tissue studied. This resolution-dependent variance can be described by fractal analysis. We studied striatal dopamine re-uptake sites in 39 healthy volunteers with high-resolution single-photon emission tomography using iodine-123 labelled 2beta-carbomethoxy-3beta-(4-iodophenyl)tropane ([123I]beta-CIT). The mean fractal dimension was 1.15+/-0.07. The results indicate that regional striatal dopamine re-uptake sites involve considerable spatial heterogeneity which is higher than the uniform density (dimension=1.00) but much lower than complete randomness (dimension=1.50). There was a gender difference, with females having a higher heterogeneity in both the left and the right striatum. In addition, we found striatal asymmetry (left-to-right heterogeneity ratio of 1.19+/-0.15; P<0.001), suggesting functional hemispheric lateralization consistent with the control of motor behaviour and integrative functions.

Adult↗

Eukaryotic membrane traffic: retrieval and retention mechanisms to achieve organelle residence.

The localization of integral membrane proteins to specific organelles is necessary to maintain the functional integrity of eukaryotic cells. Recent studies indicate firstly, that retrieval and retention mechanisms, requiring specific primary sequence motifs, are used to ensure that proteins reside in specific membranes of the secretory and endocytic pathways and secondly, that these membranes exist as components of two juxtaposed systems separated by the cisternae of the Golgi stack.

Amino Acid Sequence↗

Application of sulforaphane: histopathological study of intraportal transplanted pancreatic islets into livers of diabetic rats.

BACKGROUND: Islet cell transplantation is a promising method to restore insulin independence to patients with type 1 diabetes mellitus. A main problem in clinical islet transplantation is the fact that only a small percentage of allogeneic islet-transplanted type 1 diabetic patients can completely omit insulin injections after transplantation. One reason for the impaired survival of islet grafts is aberration of the function of islets due to toxic agents, including oxygen radicals and nitric oxide, which arise during warm or cold ischemic time. Therefore, in clinical islet transplantation, islets have been preserved with a mixture of antioxidants to reduce free radical-mediated damage of transplanted beta cells. Our aim was to examine hepatic tissue after metabolic normalization following intraportal islet transplantation after application of sulforaphane. MATERIALS AND METHODS: Islets were isolated from pancreata of WAG rats. Sulforaphane (24 mg/kg) was administered 24 hours before isolated islets were transplanted into the liver through the portal vein (1200 +/- 100 per rat). At 9 months after transplantation the animals were killed and liver tissue removed for morphological examination. RESULTS: This report indicated that the intrahepatic portal vein site was indeed an excellent locus for implantation of free pancreatic islets. The islet grafts developed rich vascularization derived from both venous and arterial sources. The islet cells maintained their structural and functional integrity after implantation. CONCLUSION: Our results showed that sulforaphane improved islet function in vivo, indicating that combination of a free radical scavenger and an antioxidant (sulforaphane) may be used to increase the effectiveness of islet transplantation.

Animals↗

Impaired functionality of reperfused brain tissue following short transient focal ischemia in rats.

Functional magnetic resonance imaging (fMRI) has been applied to study the consequences of transient focal ischemia on neuronal excitability in the rat brain. The experimental paradigm consisted of measuring the changes in local cerebral blood volume (CBV) induced by systemic infusion of the GABA(A) antagonist bicuculline after occlusion of the middle cerebral artery (MCA) for durations of 5, 15, 30 and 60 min using the intraluminal thread model. fMRI studies were carried out 60 min after successful reperfusion of the ischemic territory. Bicuculline-induced dynamic changes in local CBV were assessed in three brain regions: Parietal cortex, caudate putamen and thalamus. The measured CBV response was negatively correlated with the ischemia duration. Additionally, the three regions showed different vulnerability to the transient MCA occlusion, caudate being the most susceptible followed by parietal cortex and thalamus. The fMRI signals weakly correlated with basal CBF and CBV following reperfusion. Our results indicate that fMRI is a sensitive method to assess functional integrity of the brain. Activation maps allow to quantitatively assess the functionally compromized territory at an early stage following the ischemic event prior to the manifestation of pathomorphological changes.

Animals↗

Effective PET and ICT switching of boradiazaindacene emission: a unimolecular, emission-mode, molecular half-subtractor with reconfigurable logic gates.

[reaction, structure: see text] We report a unimolecular system functioning as a combinatorial logic circuit for half-subtractor. The emission characteristics can be modulated by chemical inputs, and when followed at two different wavelengths, two functionally integrated logic gates XOR and INHIBIT are obtained. Both logic gates function in the emission mode, and with very large differences in the signal intensity allowing unequivocal assignment of logic-0 and logic-1.

Journal Article↗

Free isotropic-nematic interfaces in fluids of charged platelike colloids.

Bulk properties and free interfaces of mixtures of charged platelike colloids and salt are studied within the density-functional theory. The particles are modeled by hard cuboids with their edges constrained to be parallel to the Cartesian axes corresponding to the Zwanzig model. The charges of the particles are concentrated in their center. The density functional is derived by functional integration of an extension of the Debye-Hückel pair distribution function with respect to the interaction potential. For sufficiently small macroion charges, the bulk phase diagrams exhibit one isotropic and one nematic phase separated by a first-order phase transition. With increasing platelet charge, the isotropic and nematic binodals are shifted to higher densities. The Donnan potential between the coexisting isotropic and nematic phases is inferred from bulk structure calculations. Nonmonotonic density and nematic order parameter profiles are found at a free interface interpolating between the coexisting isotropic and nematic bulk phases. Moreover, electrically charged layers form at the free interface leading to monotonically varying electrostatic potential profiles. Both the widths of the free interfaces and the bulk correlation lengths are approximately given by the Debye length. For fixed salt density, the interfacial tension decreases upon increasing the macroion charge.

Journal Article↗

Altered ratios of alternatively spliced long and short gamma2 subunit mRNAs of the gamma-amino butyrate type A receptor in prefrontal cortex of schizophrenics.

The relative abundance of alternatively spliced long (gamma2L) and short (gamma2S) mRNAs of the gamma2 subunit of the gamma-amino butyrate type A (GABAA) receptor was examined in dorsolateral prefrontal cortex of schizophrenics and matched controls by using in situ hybridization histochemistry and semiquantitative reverse transcription-PCR (RT-PCR) amplification. A cRNA probe identifying both mRNAs showed that the transcripts are normally expressed at moderately high levels in the prefrontal cortex. Consistent with previous studies, overall levels of gamma2 transcripts in prefrontal cortex of brains from schizophrenics were reduced by 28.0%, although this reduction did not reach statistical significance. RT-PCR, performed under nonsaturating conditions on total RNA from the same blocks of tissue used for in situ hybridization histochemistry, revealed a marked reduction in the relative proportion of gamma2S transcripts in schizophrenic brains compared with controls. In schizophrenics, gamma2S transcripts had fallen to 51.7% (+/-7.9% SE; P < 0.0001) relative to control levels. Levels of gamma2L transcripts showed only a small and nonsignificant reduction of 16. 9% (+/-12.0% SE, P > 0.05). These findings indicate differential transcriptional regulation of two functionally distinct isoforms of one of the major GABAA receptor subunits in the prefrontal cortex of schizophrenics. The specific reduction in relative abundance of gamma2S mRNAs and the associated relative increase in gamma2L mRNAs should result in functionally less active GABAA receptors and have severe consequences for cortical integrative function.

Adult↗

Hemisphere memory differences in Sodium Amytal testing of epileptic patients.

Material-specific memory performance was studied by a Sodium Amytal testing procedure in order to diagnose hemispheric memory functions in 27 patients with unilateral temporal or frontal epileptic lesions who were under consideration for surgical therapy. Memory was tested for concrete and abstract words, pictures of common objects, figures, and faces, presented pre- and post-inactivation of the hemisphere contralateral or ipsilateral to the epileptic focus. The results showed that tests involving words and pictures of common objects were conclusive about hemispheric memory functions, in showing cross-over interactions between side of lesion and side of injection. Figures and faces were hemisphere discriminative to a much lesser degree (only a minor preference for the right hemisphere was found) and are presumably more dependent on the functional integrity of both hemispheres. The present findings demonstrate that hemispheric memory functions can be studied in more detail with the Amytal technique than has been shown hitherto in the literature.

Amobarbital↗

Specific roles of protein-phospholipid interactions in the yeast cytochrome bc1 complex structure.

Biochemical data have shown that specific, tightly bound phospholipids are essential for activity of the cytochrome bc1 complex (QCR), an integral membrane protein of the respiratory chain. However, the structure and function of such phospholipids are not yet known. Here we describe five phospholipid molecules and one detergent molecule in the X-ray structure of yeast QCR at 2.3 A resolution. Their individual binding sites suggest specific roles in facilitating structural and functional integrity of the enzyme. Interestingly, a phosphatidylinositol molecule is bound in an unusual interhelical position near the flexible linker region of the Rieske iron-sulfur protein. Two possible proton uptake pathways at the ubiquinone reduction site have been identified: the E/R and the CL/K pathway. Remarkably, cardiolipin is positioned at the entrance to the latter. We propose that cardiolipin ensures structural integrity of the proton-conducting protein environment and takes part directly in proton uptake. Site-directed mutagenesis of ligating residues confirmed the importance of the phosphatidylinositol- and cardiolipin-binding sites.

Binding Sites↗

Conceptual issues in developmental screening and assessment.

Effective screening requires an understanding of underlying conceptual issues and their relationship to pragmatic concerns. Pragmatic concerns include the concepts that there are many underlying reasons for an "abnormal" screening result; that sensitivity and specificity should be combined with relative risk when considering developmental outcome; and that patterns of congruence among motor, language, cognitive, and adaptive/personal social areas of development should be considered. Important conceptual issues include the following: there is continuity of underlying processes or functions in development; canalized behaviors might give the appearance of discontinuity; integrated functions are more predictive of later developmental levels than are individual functions; the "window" of assessment and the developmental emergence of a specific function will affect screening results; one must consider biologic and environmental risks and their specific effects; and different types of neural structures and their relationship to environmental input help to explain why screening results vary over time.

Child Development↗