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1.
Alport syndrome (AS) is caused by mutations in collagen IV, which is widespread in the basement membranes of many organs, including the kidneys, eyes, and ears. Whereas the effects of collagen IV changes in the cochlea are well known, no changes have been described in the posterior labyrinth. The aim of this study was to investigate both the auditory and the vestibular function of a group of individuals with AS. Seventeen patients, aged 9–52, underwent audiological tests including pure‐tone and speech audiometry, immittance test and otoacoustic emissions and vestibular tests including video head impulse test, rotatory test, and vestibular evoked myogenic potentials. Hearing loss affected 25% of the males and 27.3% of the females with X‐linked AS. It was sensorineural with a cochlear localization and a variable severity. 50% of the males and 45.4% of the females had a hearing impairment in the high‐frequency range. Otoacoustic emissions were absent in about one‐third of the individuals. A peripheral vestibular dysfunction was present in 75% of the males and 45.4% of the females, with no complaints of vertigo or dizziness. The vestibular impairment was compensated and the vestibulo‐ocular reflex asymmetry was more evident in rotatory tests carried out at lower than higher speeds; a vestibular hypofunction was present in all hearing impaired ears although it was also found in subjects with normal hearing. A posterior labyrinth injury should be hypothesized in AS even when the patient does not manifest hearing disorders or evident signs of renal failure.  相似文献   
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Cardiopulmonary bypass (CPB) in infants is associated with morbidity due to systemic inflammatory response syndrome (SIRS). Strategies to mitigate SIRS include management of perfusion temperature, hemodilution, circuit miniaturization, and biocompatibility. Traditionally, perfusion parameters have been based on body weight. However, intraoperative monitoring of systemic and cerebral metabolic parameters suggest that often, nominal CPB flows may be overestimated. The aim of the study was to assess the safety and efficacy of continuous metabolic monitoring to manage CPB in infants during open‐heart repair. Between December 2013 and October 2014, 31 consecutive neonates, infants, and young children undergoing surgery using normothermic CPB were enrolled. There were 18 male and 13 female infants, aged 1.4 ± 1.7 years, with a mean body weight of 7.8 ± 3.8 kg and body surface area of 0.39 m2. The study was divided into two phases: (i) safety assessment; the first 20 patients were managed according to conventional CPB flows (150 mL/min/kg), except for a 20‐min test during which CPB was adjusted to the minimum flow to maintain MVO2 >70% and rSO2 >45% (group A); (ii) efficacy assessment; the following 11 patients were exclusively managed adjusting flows to maintain MVO2 >70% and rSO2 >45% for the entire duration of CPB (group B). Hemodynamic, metabolic, and clinical variables were compared within and between patient groups. Demographic variables were comparable in the two groups. In group A, the 20‐min test allowed reduction of CPB flows greater than 10%, with no impact on pH, blood gas exchange, and lactate. In group B, metabolic monitoring resulted in no significant variation of endpoint parameters, when compared with group A patients (standard CPB), except for a 10% reduction of nominal flows. There was no mortality and no neurologic morbidity in either group. Morbidity was comparable in the two groups, including: inotropic and/or mechanical circulatory support (8 vs. 1, group A vs. B, P = 0.07), reexploration for bleeding (1 vs. none, P = not significant [NS]), renal failure requiring dialysis (none vs. 1, P = NS), prolonged ventilation (9 vs. 4, P = NS), and sepsis (2 vs. 1, P = NS). The present study shows that normothermic CPB in neonates, infants, and young children can be safely managed exclusively by systemic and cerebral metabolic monitoring. This strategy allows reduction of at least 10% of predicted CPB flows under normothermia and may lay the ground for further tailoring of CPB parameters to individual patient needs.  相似文献   
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The frequency and distribution of herpesvirus-like DNA sequences (KSHV) were investigated by PCR in the pathologic skin lesions of a series of 22 HIV-negative elderly patients with classic Kaposi's sarcoma (KS) from Italy, one of the few regions of the world where classic KS is prevalent. Viral sequences were clearly identifiable in 15 cases, in particular in 2 of 5 patch, in 3 of 6 plaque and in 10 of 11 nodular lesions. Our findings confirm the association of these herpesvirus-like DNA sequences with KS in unrelated populations, providing evidence of the putative KS-associated agent in all different histologic lesions of the disease, mainly in the nodular stage. The search for other herpesviruses by PCR showed that Epstein-Barr virus (EBV) sequences were present in 7 of 22 pathologic skin lesions. In 4 cases, both EBV and KSHV were present. On the contrary, all 22 classic KS specimens were negative for human herpesvirus-6 sequences. Two of 3 patch and the 1 nodular lesions from AIDS-related KS patients examined were positive for KSHV but negative for both EBV and HHV-6 sequences. Furthermore, we evaluated the prevalence of KSHV sequences in the normal population of the same geographical area. Thirteen peripheral blood mononuclear cell samples, 9 salivary gland tissues and 6 saliva samples from healthy subjects were invariably found negative for KSHV, using the same PCR technique. Of interest, 2 of 11 hyperplastic tonsils harboured these herpesvirus-like sequences, suggesting that, like other herpesviruses, the KS-associated agent may be harboured in a proportion of normal individuals and tonsils may represent at least one of the possible reservoirs of this putative lymphotropic γ-herpesvirus in vivo. © 1996 Wiley-Liss, Inc.  相似文献   
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The widespread use of scrotal ultrasonography (US) has led to increased detection of testicular and extratesticular pathologies. Cystic or encapsulated fluid collections are relatively common benign lesions that usually present as palpable testicular lumps. Most cysts arise in the epidydimis, but all anatomical structures of the scrotum can be the site of their origin. US may suggest a specific diagnosis for a wide variety of intrascrotal cystic and fluid lesions and appropriately guide therapeutic options. US should be used as an adjunctive diagnostic modality after clinical evaluation of a scrotal lesion associated or not with the presence of a lump.  相似文献   
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In the last few years, three new herpesviruses, HHV-6, -7 and -8, have been discovered, which share interesting biological characteristics for a possible role in the development of both neurological and lymphoproliferative diseases. In particular HHV-8, besides being strongly associated with Kaposi's sarcoma, is related with several lymphoproliferative diseases. More recently, specific viral sequences belonging to HHV-8 have been detected in autoptic brain specimens from multiple sclerosis patients and controls, suggesting that, similarly to HHV-6, this novel herpesvirus is strongly neurotropic. HHV-8 is an unusual herpesvirus in that it is able to produce homologues of several human gene products, resulting in alterations in cell cycle, in apoptosis and cell-mediated immune responses. To verify a possible relationship between HHV-8 and the development of amyotrophic lateral sclerosis (ALS), we investigated the presence of signs of HHV-8 infection, by both nested polymerase chain reaction (nPCR) and indirect immune fluorescence analysis in ALS patients. Both PCR and serological data did not suggest a clear role of this virus in originating ALS. Nevertheless, new insights into the mechanisms by which viruses may interact with the host cell genome and with the human immune system make the viral hypothesis of ALS still worthy of further studies.  相似文献   
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Imaging of the acute scrotum   总被引:8,自引:0,他引:8  
The scrotum is a superficial structure and clinical examination is frequently not enough for making a specific diagnosis. In acute scrotal pain US can confirm the presumptive clinical diagnosis and provide additional relevant information. In testicular torsion, color-Doppler imaging has a central role since it has become possible to identify it at early stage by showing absence of perfusion in the affected testis before any gray-scale abnormality. Scintigraphy remains a satisfactory alternative in evaluating testicular torsion and should be used when color Doppler is inadequate, raising doubts about the suspected torsion. Diagnosis of torsion of testicular appendages is particularly difficult. Ischemic infarction shows a characteristic pattern at gray-scale and color-Doppler imaging, whereas hemorrhagic ischemia may require MRI. Inflammatory diseases of the scrotum can be easily investigated by echo color Doppler and conventional radiography, and CT can be particularly useful in the detection of gas bubbles. In scrotal trauma, scrotal hematoma, hematocele, intratesticular hematoma, and testicular rupture can be identified using gray-scale US with very good reliability. Magnetic resonance imaging is indicated when a small tear of tunica albuginea is suspected but not visualized on US. Received: 3 May 2000/Accepted: 8 June 2000  相似文献   
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Seabra AB  De Oliveira MG 《Biomaterials》2004,25(17):3773-3782
The nitric oxide (NO) donor S-nitrosoglutathione (GSNO) was incorporated in solid polymeric films of poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP) and blended PVA/PVP. These matrices were found to provide a great stabilization effect on the thermal decomposition of GSNO, leading to 8-16-fold reduction in the first-order rate constants of NO release, compared to aqueous GSNO solutions. PVA/PVP-GSNO released 90% of the NO supply, over a time period of 24h at 37 degrees C. Differential scanning calorimetry has confirmed the miscibility between the two polymeric components. Stress-strain analysis has shown an improvement of the mechanical property of PVA films in the PVA/PVP blend, which leads to an increase of 25% in the stress at break. Scanning electron microscopy has shown that the PVA/PVP-GSNO blend leads to a smooth coating of metallic surfaces. These properties, allied to the already known good biocompatibility of PVA and PVP, makes GSNO-containing PVA and PVA/PVP blend films good candidates for the local and controlled release of NO in target areas.  相似文献   
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