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Cognitive impairment is one of the most common neurological disorders in neuro-oncological patients and exerts a deep negative impact on quality of life interfering with familiar, social and career-related activities. To test the effectiveness of early cognitive rehabilitation treatment for inpatients affected by primary brain tumors. Out of 109 consecutive patients enrolled in the study, 58 patients were randomly assigned to a rehabilitation group or to a control group. The rehabilitation consisted of 16 one-hour individual sessions of therapist-guided cognitive training, spread over 4 weeks, combining computer exercises and metacognitive training. Patients in the control group received usual care without cognitive training. All patients were evaluated by means of a comprehensive neuropsychological battery at the admission (T0) and after 4 weeks (T1). Patients in the rehabilitation group showed a significant improvement of cognitive functions. In particular, the domains that benefited most from the training were visual attention and verbal memory. The control group exhibited only a slightly, not statistically relevant, enhancement of cognitive performances. Cognitive rehabilitation for neuro-oncological inpatients resulted in a significant enhancement of cognitive performances after the training, also providing a foundation for early administration. Future research should be aimed to clarify the patients’ characteristics that predict neuropsychological improvement, to identify the most effective elements in rehabilitative programs and to study the effects of treatment extension to everyday life.  相似文献   
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The endoscopic endonasal transsphenoidal approach to the sellar region for the removal of pituitary adenomas and of other neoplasms in the same area has proved its reliability and effectiveness for the very wide vision it offers, coupled with minimal surgical trauma. Indications and advantages of such a technique are reported, focused on the treatment of lesions of the sellar and parasellar environment in pediatric age-group patients, and based on a consecutive series of 100 patients, 3 of them adolescents, treated during the last 3 years.  相似文献   
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OBJECTIVE: To evaluate the effect of heterotopic painful stimulation (HPS) on the cutaneous silent period (CSP) and the withdrawal flexor reflex (WFR) in the upper limbs, in an attempt to better identify the nociceptive component of the CSP and its functional relationship with the flexor reflex. METHODS: The CSP at different stimulus intensities, the WFR and the H/M ratio were studied in 12 healthy adults. Neurophysiological measurements were recorded in the following 4 conditions: (1) control session; (2) non-painful session (dipping hand in water at 25 degrees C); (3) painful (cold pressor test, CPT); and (4) after-effect (3-8 min after taking hand out of water at 5-6 degrees C). RESULTS: During the CPT, the duration of the high-threshold CSP was approximately 23% shorter than the baseline value, the high-threshold CSP latency was approximately 10% longer than the baseline value, and the mean RIII reflex area was approximately 40% smaller than the baseline reflex area (all P<0.05). A significant correlation was found between the percentage decrease in the CSP duration and the WFR area (r=0.61, P<0.05). CONCLUSIONS: Our findings indicate that the HPS specifically inhibits both the high-threshold CSP and the WFR, thereby providing further evidence that these cutaneous reflexes are functionally and anatomically related, and that they represent different aspects of a complex nocifensive response.  相似文献   
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The expression of alpha V integrins by neoplastic cells contributes to the promotion of local invasion and metastasis. The most characteristic extracellular ligands of alpha V integrins are vitronectin and fibronectin. Hepatocytes are the main source of vitronectin, and the capacity to synthesize and secrete vitronectin is usually retained in hepatocellular carcinoma. The aim of this study was to explore the expression, regulation, and functional role of alpha V integrins in hepatocellular carcinoma. We first analyzed the expression of alpha V integrins and their ligands fibronectin and vitronectin in 80 cases of hepatocellular carcinoma. alpha V integrin chain was detected in 44 cases and vitronectin in 50. Twenty-four of the 44 alpha V-positive tumors contained large amounts of vitronectin. These cases presented more frequently with adverse histoprognostic factors, including infiltrative growth pattern (62.5%), lack of capsule (71%), presence of capsular invasion (57%), and satellite nodules (50%). We then used HepG2 and Hep3B cell lines as in vitro models to study alpha V integrin regulation and function. HepG2 and Hep3B cells expressed alpha V integrin chain and used alpha V beta 1 and alpha V beta 5 for adhesion and migration on vitronectin. Tumor necrosis factor (TNF) alpha and transforming growth factor (TGF) beta significantly increased the expression levels of alpha V integrins and stimulated the adhesion and migration of both HepG2 and Hep3B cell lines on vitronectin. The effects of growth factors on cell adhesion and migration were reproduced by incubation with conditioned medium from rat liver myofibroblasts. In conclusion, our results support the existence of an alpha V integrin/vitronectin connection in hepatocellular carcinoma and suggest that this connection may be an adverse prognostic factor.  相似文献   
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Although hyponatremia is known to be associated with osteoporosis and a high fracture risk, the mechanism through which bone loss ensues has remained unclear. As hyponatremic patients have elevated circulating arginine-vasopressin (AVP) levels, we examined whether AVP can affect the skeleton directly as yet another component of the pituitary-bone axis. Here, we report that the two Avp receptors, Avpr1α and Avpr2, coupled to Erk activation, are expressed in osteoblasts and osteoclasts. AVP injected into wild-type mice enhanced and reduced, respectively, the formation of bone-resorbing osteoclasts and bone-forming osteoblasts. Conversely, the exposure of osteoblast precursors to Avpr1α or Avpr2 antagonists, namely SR49059 or ADAM, increased osteoblastogenesis, as did the genetic deletion of Avpr1α. In contrast, osteoclast formation and bone resorption were both reduced in Avpr1α−/− cultures. This process increased bone formation and reduced resorption resulted in a profound enhancement of bone mass in Avpr1α−/− mice and in wild-type mice injected with SR49059. Collectively, the data not only establish a primary role for Avp signaling in bone mass regulation, but also call for further studies on the skeletal actions of Avpr inhibitors used commonly in hyponatremic patients.Over the past decade, studies by others and us have documented direct effects of pituitary hormones on the skeleton. We have identified functional receptors for thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), adrenocorticotropic hormone (ACTH), and oxytocin (OT) on murine and human bone cells, namely bone-forming osteoblasts and bone-resorbing osteoclasts (14). The genetic deletion of either the receptor or the ligand itself, as in the case of FSH and OT, results in overt skeletal abnormalities. Specifically, deleting OT or its receptor, the Oxtr, causes profound osteopenia, which primarily arises from a dramatic reduction in bone formation by the osteoblast (4). Such studies have helped establish a pituitary-bone axis, in which pituitary hormones bypass their known targets, such as the thyroid, ovaries, adrenal, and breast, to regulate bone directly (5).This growing body of data not only informs us of novel functions of pituitary hormones, but also explains the hitherto poorly understood mechanisms of certain forms of osteoporosis, which have traditionally been attributed solely to changes in distal hormones. For example, we find that low TSH signaling contributes to the bone loss in hyperthyroidism, which was thought solely to be a result of elevated thyroid hormones (6). We have also speculated that the rapid bone loss that occurs during late perimenopause, at a time when estradiol levels are relatively normal, could—at least in part—be caused by elevated serum FSH levels. Thus, an antibody to FSH reduces bone loss in ovariectomized mice by stimulating bone formation and inhibiting bone resorption (7). Similarly, through its skeletal anabolic actions, elevated OT levels during pregnancy and lactation could play a major role in enabling fetal skeletal mineralization and allowing the mother to recover from the osteoporosis caused by the intergenerational transfer of calcium (8).Here, we report studies on arginine-vasopressin (AVP), another posterior pituitary hormone, which differs from OT only by two amino acids (9). The direct skeletal actions of AVP have never been explored, despite multiple and recurring observations that hyponatremia, which is invariably accompanied by elevated plasma AVP levels, is associated with bone loss and a high fracture risk (1016). It has been thought that, as bone is a large reservoir for sodium ions, hyponatremia will trigger sodium release from the skeleton by increasing bone resorption (17, 18). However, the molecular basis of any such effect remains unknown. Interestingly, a recent study has described a male patient with syndrome of inappropriate secretion of antidiuretic hormone- (SIADH) induced hyponatremia, who had severe osteoporosis, despite having no identifiable risk factors (19). Plasma AVP was elevated by ∼30-fold, raising the possibility that high circulating AVP levels may cause the profound bone loss.We show that AVP is a key regulator of bone resorption and formation, the two principal components of bone remodeling. Both Avp receptors, Avpr1α and Avpr2, are expressed on osteoclasts and osteoblasts, and their stimulation triggers extracellular signal regulated kinase (Erk) activation, which in turn suppresses bone formation and stimulates bone resorption. This decoupling would favor bone loss, as noted in hyponatremic states. However, we also find that the genetic deletion of Avpr1 or the pharmacologic inhibition of Avpr1 or Avpr2 increases bone mass not only by stimulating osteoblastogenesis and new bone synthesis, but also by simultaneously inhibiting osteoclast formation and bone resorption. We speculate, therefore, that the targeted therapy of hyponatremia with aquaretics (or AVPR inhibitors) could result in overall bone gain. Purposefully designed clinical studies in populations in whom hyponatremia is a significant clinical problem (20), and whom are otherwise also at a high risk for fracture (21), should shed further light on the proposed osteoprotective action of AVPR antagonists in people.  相似文献   
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Everywhere you turn these days there seems to be another report about the alarming breakdown in safe sex among gay men. In a current study financed by the US Centers for Disease Control and Prevention, two-thirds of the gay men participating say they had unprotected sex in the previous 18 months. After levelling off in the late eighties, the HIV infection rate among gay men is once again on the rise. These reports have not surprised me. In moments of profound carelessness, I habe also engaged in unsafe sex. Now I find myself in total uncertainty about my HIV status, yet am fearful ofbeing tested. The chilling statistics, combined with my own predicament make me question the message most AIDS organisations have been sending in their safer sex education campaigns. In general, they have refused to emphasise the particular responsibilities of HIV positive men, and have not been attentive to the needs of HIV negative men, who often feel guiltridden because they are still healthy and who still refuse to admit their vulnerability.  相似文献   
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