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91.
Pediatric Surgery International - Since Hirschsprung’s disease (HSCR) already proved to benefit from robotic surgery, we aimed at describing a wider series of patients with this rare disease...  相似文献   
92.
We aimed at the further characterization of rats in which SERT gene silencing was achieved by hippocampal injection of a lentiviral vector, carrying three si-RNA to block SERT mRNA at 66% of normal levels. Improved self-control and reduced restlessness were already demonstrated in these rats. Present further studies consisted of male adult rats, bilaterally inoculated within the hippocampus; control rats received lentivirus particles inactivated with heat. Both groups were maintained in isolation for 5 months, starting from inoculation. Neurochemical changes were studied by proton magnetic resonance spectroscopy (1H-MRS): we found increased hippocampal viability and bioenergetic potential; however, rats showed a behaviorally depressive pattern, also characterized by enhanced affiliation. Based on the extent of such effects, the whole lenti-SERT group was divided into two subgroups, termed intermediate- and extreme- phenotype profiles. While all rats had a widespread modification within dorsal/ventral striatum, amygdala, and hypothalamus, only the former subgroup showed an involvement of Raphé medialis, while, for the latter subgroup, an increase of SERT within hippocampus was unexpectedly caused. Within the less-affected “intermediate” rats, hippocampal 5-HT7 receptors were down-modulated, and also similarly within substantia nigra, septum, and neocortex. This picture demonstrates that additional rather than fewer neurobiological changes accompany a lower phenotypic expression. Overall, tapping hippocampal SERT affected the balance between habits versus strategies of coping by promoting morphogenetic processes indicative of a serotonergic fiber plasticity. Supplementary studies about serotonergic dynamics and neurogenesis within fronto-striatal circuits are needed.  相似文献   
93.
CD34 is a transmembrane protein that is strongly expressed on hematopoietic stem/progenitor cells (HSCs); despite its importance as a marker of HSCs, its function is still poorly understood, although a role in cell adhesion has been demonstrated. To characterize the function of CD34 antigen on human HSCs, we examined, by both inhibition and overexpression, the role of CD34 in the regulation of HSC lineage differentiation. Our results demonstrate that CD34 silencing enhances HSC granulocyte and megakaryocyte differentiation and reduces erythroid maturation. In agreement with these results, the gene expression profile of these cells reveals the upregulation of genes involved in granulocyte and megakaryocyte differentiation and the downregulation of erythroid genes. Consistently, retroviral-mediated CD34 overexpression leads to a remarkable increase in erythroid progenitors and a dramatic decrease in granulocyte progenitors, as evaluated by clonogenic assay. Together, these data indicate that the CD34 molecule promotes the differentiation of CD34+ hematopoietic progenitors toward the erythroid lineage, which is achieved, at least in part, at the expense of granulocyte and megakaryocyte lineages.  相似文献   
94.
A well established model for the pathophysiology of schizophrenia postulates a role for the NMDA-mediated glutamate transmission. The human gene coding for the 2B subunit of the NMDA receptor (GRIN2B) is considered a candidate based on its selective expression in brain. To evaluate the hypothesis that GRIN2B acts as a major gene in determining susceptibility to schizophrenia, a case-control association study was performed. Five single nucleotide polymorphisms (SNPs) were genotyped in 188 Italian patients and 156 control subjects. The association study showed a marginally significant excess of homozygosity for the polymorphism located in the 3'UTR region (P = 0.04). No other difference in genotype and allele frequencies was found in schizophrenics as compared to the control series. The case-control study was also carried out on estimated haplotypes, confirming a trend for association (P = 0.04). These results suggest that GRIN2B variations might be linked with susceptibility to schizophrenia. Replication studies on larger samples are warranted to further test this hypothesis.  相似文献   
95.
Objective.— In this study, we evaluated the influence of sex and estrogen treatment on nitroglycerin (NTG)‐induced neuronal activation in the rat brain. Background.— Systemic NTG activates cerebral nuclei of rat involved in nociceptive transmission, as well as in neuroendocrine and autonomic functions. These changes are considered relevant for migraine, since NTG consistently induces spontaneous‐like attacks in migraineurs. Methods.— Intact and castrated male and female rats, and castrated female rats treated with estradiol benzoate (or placebo) were injected with NTG and sacrificed after 4 hours. Rats were perfused, and their brains were processed for Fos protein, a marker of neuronal activation. Results.— Data showed a reduced expression of NTG‐induced Fos protein in the paraventricular nucleus (PVH), supraoptic nucleus (SON), and nucleus trigeminalis caudalis (SPVC) of male rats in comparison with female rats. Furthermore, in castrated female rats, NTG‐induced neuronal activation was reduced in PVH, SON, central nucleus of the amygdala (AMI), nucleus tractus solitarius (NTS), area postrema (AP), and SPVC, while in castrated male rats Fos expression was reduced uniquely in the SPVC. Chronic administration of estrogens restored Fos protein expression in PVH, SON, AMI, NTS, AP, and SPVC in castrated female rats. Conclusion.— These data provide a support for the existence of a sexual dimorphism in NTG‐induced neuronal activation, and they prompt a specific model for evaluating and modulating the influence of estrogens upon the cerebral structures implicated in the pathophysiology of migraine.  相似文献   
96.
Glaucoma,a progressive age-related optic neuropathy characterized by the death of retinal ganglion cells,is the most common neurodegenerative cause of irreversible blindness worldwide.The therapeutic management of glaucoma,which is limited to lowering intraocular pressure,is still a challenge since visual loss progresses in a significant percentage of treated patients.Restricted dietary regimens have received considerable attention as adjuvant strategy for attenuating or delaying the progression of neurodegenerative diseases.Here we discuss the literature exploring the effects of modified eating patterns on retinal aging and resistance to stressor stimuli.  相似文献   
97.
98.
Inflammatory breast cancer is a rare and aggressive form of breast cancer. Venous thromboembolism is often related to cancer conditions but this report presents a case in which the thromboembolic event predicted the diagnosis of cancer. A 48-year-old female was admitted with the evidence of acute right axillary vein thrombosis. There was also erythema and edema of the skin of the right breast. Further evidence revealed a case of inflammatory breast cancer. The patient underwent anticoagulant therapy, and neoadjuvant systemic chemotherapy was initiated. The patient underwent extensive unilateral mastectomy following neoadjuvant chemotherapy. Follow-up (after 2 months of anticoagulation therapy for deep vein thrombosis) revealed recanalization of the right axillary vein, without evidence of residual thrombus. A case of acute vein thrombosis as the first manifestation of breast cancer may delay the diagnosis and subsequent appropriate treatment.  相似文献   
99.
Venous ulcers are common, especially in the elderly, accounting for more than 50% of all lower extremity ulcers with important socioeconomic problems. Improving extracellular matrix functioning, by heparin administration, seems to be a way to support wound healing. A total of 284 patients with venous ulcers were recruited in a 4‐year period. All patients were subjected to the most appropriate treatment after considering their preference (compression therapy followed or not by vein surgery). Patients were randomised into two groups of 142 persons in each (group A and group B as cases and controls, respectively). Patients of group A, in addition to the basic treatment as described earlier, received administration of nadroparin 2850 IU/0.3 ml through subcutaneous injection once a day for 12 months, whereas group B patients received basic treatment alone. Healing was assessed by means of direct ulcer tracing with computerised planimetry. Group A showed a healing rate of 83·80% at 12 months, whereas that of group B was 60·56%. Results by age group surprisingly showed that the group of older patients took the most advantage from long‐term treatment with low molecular weight heparin; this group also had lowest recurrence rate.  相似文献   
100.
Laparoscopic splenectomy (LS) is now considered the procedure of choice for removal of the spleen in several hematologic and traumatic splenic conditions. Perisplenitis is still considered a relative contraindication. We report a rare case of isolated splenic candidiasis treated by laparoscopic splenectomy. The technical challenges of the laparoscopic approach in cases of perisplenitis are outlined. Because of dense adhesions to the diaphragm, the LS was converted to open splenectomy, and the procedure was completed through a small subcostal incision. This case report suggests the need for and effectiveness of splenectomy in patients whose fungal infection is suspected to be localized to the spleen. Laparoscopic removal of the spleen in these cases is very difficult to accomplish because of the risk for diaphragm injuries and the technical problems encountered.  相似文献   
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