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121.
Submicroscopic alterations in the cytoskeletal structure of sperm flagellum are associated with severely reduced or completely absent motility in subfertile or infertile men. Sometimes these alterations can be related to well known genotypic defects when the same anomaly affects the whole sperm population. Transmission electron microscopy (TEM) is the only tool able to specifically characterize the morphological features of genetic sperm defects. In this study, the frequencies of aneuploid and diploid spermatozoa were identified in three patients showing specific flagellar anomalies, each of them affecting the whole sperm population: dysplasia of the fibrous sheath, primary ciliary dyskinesia and absence of fibrous sheath. All these defects were highlighted by TEM. Fluorescence in situ hybridization (FISH) analysis was performed on decondensed sperm nuclei for chromosomes 18, X and Y, highlighting higher diploidies and sex chromosome disomies in cases of dysplasia of the fibrous sheath and primary ciliary dyskinesia, in agreement with other reports. We have also described FISH results in spermatozoa with absence of fibrous sheath. In this case, the only one reported due to the rarity of this defect, the aneuploidies and diploidies were within normal range. These data contribute to the growing evidence that genetic sperm defects of sperm flagella are generally correlated with meiotic segregation derangement. For this reason, genetic counseling is advisable, although all the genes involved and the possible mechanisms of these mutations have not yet been fully characterized.  相似文献   
122.
BACKGROUND: Peculiar sperm defects are described in a sterile man heterozygous for a balanced translocation t(10;15) (q26;q12). As this structural reorganization was absent in the parents, the translocation must have appeared de novo in the present patient. METHODS: Spermatozoa were analysed under light and transmission electron microscopy (TEM). Fluorescence in-situ hybridization (FISH) was performed on the lymphocyte karyotype. Aneuploidy frequencies of chromosomes 18, X and Y in sperm nuclei, not involved in the translocation, were investigated using three-colour FISH. Dual- colour FISH was used to evaluate segregation of chromosomes 10, 15 in decondensed sperm nuclei. Moreover, three-colour FISH, using telomeric probes for chromosomes 10, 15 was performed in order to distinguish balanced and unbalanced gametes. RESULTS AND CONCLUSIONS: Overall, structural characteristics indicate general immaturity of the germinal cells. FISH sperm analysis detected an increase in chromosome 18 disomy (0.81%) suggesting an interchromosomal effect. A high frequency of diploidies, particularly 18,18,X,X and 18,18,X,Y, was also found. FISH segregation analysis for chromosomes 10, 15 indicated that 32.8% were balanced gametes, whereas 68.2% were unbalanced. Taken together, these data demonstrate in a male carrier of a reciprocal translocation t(10;15) the presence of diffuse ultrastructural sperm alterations and a high frequency of sperm aneuploidies. The existence of a correlation among these factors is proposed.  相似文献   
123.
IntroductionDifferent cut‐offs of the erectile function (EF) domain of the International Index of Erectile Function (IIEF) have been used as definition of postoperative EF recovery.AimTo test the correlation between patient satisfaction and IIEF‐EF domain score cut‐offs.Main Outcome MeasureThe IIEF was used to evaluate EF and satisfaction before and after bilateral nerve sparing radical prostatectomy (BNSRP).MethodsThe study included 165 consecutive patients treated with retropubic BNSRP at a single institution. All patients had normal preoperative EF (IIEF‐EF ≥ 26) and reached an IIEF‐EF ≥ 17 following surgery. Complete data included EF, intercourse (IS), and overall satisfaction (OS) assessed by the corresponding domains of the IIEF administered prior and after surgery. Patients were divided into three groups according to the highest IIEF‐EF score reached postoperatively, namely 17–21 (group 1), 22–25 (group 2), and ≥26 (group 3). One‐way analysis of variance was used to compare IIEF‐OS and IIEF‐IS domain scores at the time the EF end point was reached. The same analyses were repeated separately in those patients with a complete EF recovery after surgery (group 3).ResultsMean preoperative IIEF‐OS and IIEF‐IS domain score was 8.4, 8.8, 8.7 and 11.6, 11.8, 11.9 in group 1, 2, 3, respectively (all P ≥ 0.3). After a mean follow‐up of 26.7 months, mean postoperative IIEF‐OS and IIEF‐IS domain scores assessed at the time of EF recovery were comparable for patients reaching an IIEF‐EF of 22–25 and for patients scoring postoperatively ≥26 (8.1, 8.1, and 10.6, 11.4; all P ≥ 0.3). However, mean IIEF‐OS and IIEF‐IS domain scores of these patients were significantly higher as compared to patients reaching an IIEF‐EF domain score < 22 (6.3 and 8.4, respectively; all P ≤ 0.006). Similar results were achieved considering only those patients (group 3) who had complete EF recovery after surgery.ConclusionsWe demonstrated that in preoperatively fully potent patients treated with BNSRP a lower satisfaction is expected when an IIEF‐EF cut‐off of 17 is used. Conversely, no difference was found using a cut‐off of 22 or 26. Therefore, our results support that a cut‐off of IIEF‐EF ≥ 22 might represent a reliable score for defining EF recovery after BNSRP. Briganti A, Gallina A, Suardi N, Capitanio U, Tutolo M, Bianchi M, Salonia A, Colombo R, Di Girolamo V, Martinez‐Salamanca JI, Guazzoni G, Rigatti P, and Montorsi F. What is the definition of a satisfactory erectile function after bilateral nerve sparing radical prostatectomy?.  相似文献   
124.
It is well-known that a soap film spanning a looped wire can have the topology of a Möbius strip and that deformations of the wire can induce a transformation to a two-sided film, but the process by which this transformation is achieved has remained unknown. Experimental studies presented here show that this process consists of a collapse of the film toward the boundary that produces a previously unrecognized finite-time twist singularity that changes the linking number of the film’s Plateau border and the centerline of the wire. We conjecture that it is a general feature of this type of transition that the singularity always occurs at the surface boundary. The change in linking number is shown to be a consequence of a viscous reconnection of the Plateau border at the moment of the singularity. High-speed imaging of the collapse dynamics of the film’s throat, similar to that of the central opening of a catenoid, reveals a crossover between two power laws. Far from the singularity, it is suggested that the collapse is controlled by dissipation within the fluid film surrounding the wire, whereas closer to the transition the power law has the classical form arising from a balance between air inertia and surface tension. Analytical and numerical studies of minimal surfaces and ruled surfaces are used to gain insight into the energetics underlying the transition and the twisted geometry in the neighborhood of the singularity. A number of challenging mathematical questions arising from these observations are posed.  相似文献   
125.

Purpose  

Peptide receptor targeting has become an increasingly attractive method to target tumors diagnostically and radiotherapeutically. Peptides linked to a variety of chelators have been developed for this purpose. They have, however, rarely been tested for their agonistic or antagonistic properties. We report here on a somatostatin antagonist that switched to an agonist upon coupling to a DOTA chelator.  相似文献   
126.
For >30 yr, the ileal conduit (IC) has been considered the “standard” urinary diversion for bladder cancer patients submitted to radical cystectomy. It is universally recognised as being the most clinically adequate, cost-effective, and reliable solution in the long term. During the last two decades, this surgical procedure has been challenged by the dissemination and the excellent clinical outcome of bladder substitutions, which gave the surgeon options in supporting the patient's final choice. Despite this, from a survey of recent literature, IC remains a widely used urinary diversion in most urologic centres. In particular, it is most frequent in female patients and in patients >70 yr with high preoperative comorbidities and unfavourable clinical tumour stage.Enhanced recovery protocols with standardised perioperative plans of care or “fast-track” approaches as well as advances in postoperative patient surveillance have consistently decreased the overall morbidity related to the IC procedure. Although technically simpler to perform when compared with continent reservoirs, IC has not been associated with lower complications. This can be explained partly by the more unfavourable clinical characteristics of patients who undergo the procedure and partly by technical surgical errors. Postoperative complications strictly related to IC contribute to reduce the postoperative quality of life. These complications include uretero-ileal anastomotic strictures and stomal, peristomal, and abdominal wall-related complications. Most prospective studies, however, found no difference in overall quality of life when comparing different types of transposed intestinal segment surgery.  相似文献   
127.
ABSTRACT: BACKGROUND: Despite progresses in neonatal care, the mortality and the incidence of neuro-motor disability after perinatal asphyxia have failed to show substantial improvements. In countries with a high level of perinatal care, the incidence of asphyxia responsible for moderate or severe encephalopathy is still 2--3 per 1000 term newborns. Recent trials have demonstrated that moderate hypothermia, started within 6 hours after birth and protracted for 72 hours, can significantly improve survival and reduce neurologic impairment in neonates with hypoxic-ischemic encephalopathy. It is not currently known whether neuroprotective drugs can further improve the beneficial effects of hypothermia. Topiramate has been proven to reduce brain injury in animal models of neonatal hypoxic ischemic encephalopathy. However, the association of mild hypothermia and topiramate treatment has never been studied in human newborns. The objective of this research project is to evaluate, through a multicenter randomized controlled trial, whether the efficacy of moderate hypothermia can be increased by concomitant topiramate treatment. METHODS: Term newborns (gestational age >= 36 weeks and birth weight >= 1800 g) with precocious metabolic, clinical and electroencephalographic (EEG) signs of hypoxic-ischemic encephalopathy will be randomized, according to their EEG pattern, to receive topiramate added to standard treatment with moderate hypothermia or standard treatment alone. Topiramate will be administered at 10 mg/kg once a day for the first 3 days of life. Topiramate concentrations will be measured on serial dried blood spots. 64 participants will be recruited in the study. To evaluate the safety of topiramate administration, cardiac and respiratory parameters will be continuously monitored. Blood samplings will be performed to check renal, liver and metabolic balance. To evaluate the efficacy of topiramate, the neurologic outcome of enrolled newborns will be evaluated by serial neurologic and neuroradiologic examinations. Visual function will be evaluated by means of behavioural standardized tests. DISCUSSION: This pilot study will explore the possible therapeutic role of topiramate in combination with moderate hypothermia. Any favourable results of this research might open new perspectives about the reduction of cerebral damage in asphyxiated newborns. Trial registration Current Controlled Trials ISRCTN62175998; ClinicalTrials.gov Identifier NCT01241019; EudraCT Number 2010-018627-25.  相似文献   
128.
A missense mutation in the gene encoding the alpha(2) subunit of the Na(+),K(+) ATPase pump (ATP1A2) was found in a family with both familial hemiplegic migraine (FHM) and Benign Familial Infantile Seizures (BFIC). As it is still unclear whether ATP1A2 is responsible for pure BFIC syndromes, we checked mutations of the ATP1A2 gene in probands of 12 Italian multiplex families with pure BFIC, who were negative for mutations in the SCN2A gene. We screened the ATP1A2 gene by denaturing high performance liquid chromatography (D-HPLC) and direct sequencing of DNA fragments showing an aberrant elution pattern. We found one exonic variant and five intronic variants, none leading to significant amino acid changes or causing a modification of the physiological mRNA maturation. The ATP1A2 gene does not appear to be involved in the ethiopathogenesis of pure BFIC syndromes, at least in the explored Italian multiplex families. It could be either responsible of a minority of cases, or of complex syndromes where BFIC and FHM co-occur.  相似文献   
129.
Clostridium sordellii is an infrequent human pathogen. It has been demonstrated to be occasionally responsible for myonecrosis or gas gangrene. Interestingly, in the obstetric literature, some cases of postpartum maternal deaths have been associated with C sordellii infection causing a rapidly lethal toxin mediated syndrome. This is the first reported case of postpartum death in a 29 year old woman, in which a toxigenic C sordellii was isolated from the patient's blood antemortem during the fatal toxic shock, strongly indicating its role in this rare syndrome.  相似文献   
130.
Chronic coinfection with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) is among the greatest challenges facing public health worldwide. In this population, the response to hepatitis C therapy by treatment with pegylated interferon plus ribavirin (PEG-IFN+RBV) is lower than in HCV-monoinfected patients, particularly in those infected by HCV genotype 1. A PKR/eIF-2α phosphorylation homology domain (PePHD) within the E2 protein has been found to interact with PKR and inhibit PKR in vitro, suggesting a possible mechanism for HCV to evade the antiviral effects of IFN. The aim of this work was to analyze the amino acid conservation in the HCV-E2-PePHD and quasispecies diversity among HCV-HIV-coinfected patients exhibiting sustained virological response, non-response, or partial response with viral relapse to PEG-IFN+RBV by ultra-deep pyrosequencing. For this purpose, HCV-E2-PePHD PCR products were generated and sequenced directly for four patients with a sustained response, seven patients with no virological response, and four patients with viral relapse before and after treatment with PEG-IFN+RBV. HCV-E2-PePHD amino acid sequences were obtained for isolates from serum collected before and during treatment (24 h, 4 weeks, and 12 weeks). Quasispecies analysis of the HCV-E2-PePHD and flanking genomic regions was performed using 454/Roche pyrosequencing, analyzing 39,364 sequence reads in total. The HCV-E2-PePHD sequence at the amino acid and nucleotide level was highly conserved among HCV genotype 1 strains, irrespective of the PEG-IFN+RBV response. This high degree of amino acid conservation and sporadic mutations in the HCV-E2-PePHD domain do not appear to be associated with treatment outcome. The HCV-E2-PePHD sequence before or during treatment cannot be used to predict reliably the outcome of treatment in patients coinfected with HCV genotype 1 and HIV.  相似文献   
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