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131.
Biancheri R Pisaturo C Perrone MV Pessagno A Rossi A Veneselli E 《Neuropediatrics》2000,31(6):321-324
Leukoencephalopathy with swelling and a discrepantly mild clinical course ("van der Knaap disease") is a recently identified syndrome. It is characterised by macrocephaly occurring during the first year of life, initially normal or nearly normal development, and slowly progressive ataxia and spasticity with initial preservation of intellectual functions. MRI shows diffuse abnormality in signal intensity, as well as swelling of the hemispheral white matter with subcortical cyst-like spaces in the fronto-parietal and anterior temporal areas. It is thought to have an autosomal recessive mode of inheritance, since many patients have consanguineous parents and more than one affected patient is often present within the same family. We report on two sibs: a 5-year old boy affected with "van der Knaap disease" and his macrocephalic sister whose first MRI (2 years 6 months) showed delayed myelination, which led us to suspect the same disease as her brother, however with subsequent normalisation at the second MRI (3 years 6 months). 相似文献
132.
Neurturin (NRTN), signalling via the GDNF family receptor alpha2 (GFRalpha2) and Ret tyrosine kinase, has recently been identified as an essential target-derived factor for many parasympathetic neurons. NRTN is expressed in salivary and lacrimal glands, while GFRalpha2 and Ret are expressed in the corresponding submandibular, otic and sphenopalatine ganglia. Here, we have characterized in more detail the role of GDNF and NRTN signalling in the development of cranial parasympathetic neurons and their target innervation. Gfra1 mRNA was expressed at E12 but not in newborn cranial parasympathetic ganglia, while Gfra2 mRNA and protein were strongly expressed in newborn and adult cranial parasympathetic neurons and their projections, respectively. In newborn GFRalpha1- or Ret-deficient mice, where many submandibular ganglion neurons were still present, the otic and sphenopalatine ganglia were completely missing. In contrast, in newborn GFRalpha2-deficient mice, most neurons in all these ganglia were present. In these mice, the loss and atrophy of the submandibular and otic neurons were amplified postnatally, accompanied by complete loss of innervation in some target regions and preservation in others. Surprisingly, GFRalpha2-deficient sphenopalatine neurons, whose targets were completely uninnervated, were not reduced in number and only slightly atrophied. Thus, GDNF signalling via GFRalpha1/Ret is essential in the early gangliogenesis of some, but not all, cranial parasympathetic neurons, whereas NRTN signalling through GFRalpha2/Ret is essential for the development and maintenance of parasympathetic target innervation. These results indicate that GDNF and NRTN have distinct functions in developing parasympathetic neurons, and suggest heterogeneity among and within different parasympathetic ganglia. 相似文献
133.
Schietroma M Mattucci S Rossi M Agnifili A Pistoia MA Carlei F 《Chirurgia italiana》2000,52(3):271-277
It is well known that surgery significantly decreases cell-mediated immunity. Laparoscopic cholecystectomy is a so-called minimally invasive surgical procedure, and on the basis of this consideration we investigated whether and how the immune system is modified in patients after laparoscopic cholecystectomy compared to those undergoing open cholecystectomy. Immune activity (neutrophils, total lymphocyte count, lymphocyte subpopulations, multiple skin tests) was evaluated in 82 patients on postoperative day 1 and on postoperative days 1, 3 and 6. Forty-two patients underwent open cholecystectomy and 40 laparoscopic cholecystectomy. On postoperative day 1 patients treated by open cholecystectomy showed a significant increase (P < 0.05) in plasma neutrophils, whereas this parameter was unchanged in patients undergoing laparoscopic cholecystectomy. Skin tests revealed a hypo- or anergic response in the majority of patients (81.8%) undergoing open surgery compared to those treated laparoscopically (10.5%). Total lymphocyte count and lymphocyte subpopulations were normal in the two groups. Four cases of respiratory tract infection (4.8%) were detected after open cholecystectomy. Laparoscopic cholecystectomy substantially reduces postoperative pain and hospitalisation, promotes an earlier recovery and return to normal activity and is not associated with postoperative immunosuppression, with a more positive postoperative morbidity profile compared to open surgery. 相似文献
134.
M Lanciotti C Dufour L Corral P Di Michele S Pigullo G De Rossi G Basso A Leszl M Luciani L Lo Nigro C Micalizzi M G Valsecchi A Biondi R Haupt 《Leukemia》2005,19(2):214-216
NAD(P)H:quinone oxidoreductase 1 (NQO1) is a detoxification enzyme that protects cells against oxidative stress and toxic quinones. A polymorphism (C609T) in the gene produces in the heterozygous individuals (C/T) a reduction and in those homozygous for the variant allele (T/T) the abolishment of NQO1 protein activity. To assess whether NQO1 inactivating polymorphism (CT/TT) was a possible risk factor for infant acute lymphoblastic leukemia (iALL), we investigated the distribution of NQO1 genotype in 50 iALL patients, 32 with MLL gene rearrangements (MLL+) and 18 without (MLL-). As controls, 106 cases of pediatric ALL (pALL), and 147 healthy subjects were also studied. Compared to normal controls, the frequency of the low/null activity NQO1 genotypes was significantly higher in the iALL MLL- (72 vs 38%, P=0.006; odds ratio (OR) 4.22, 95% confidence interval (CI) 1.43-12.49), while no differences were observed in iALL MLL+ (44 vs 38%, P=0.553; OR 1.26, 95% CI 0.58-2.74). Similar results were observed when pALL were used as control. Our results indicate that only the iALL patients without MLL rearrangements had a significantly higher frequency of NQO1 genotypes associated with low/null activity enzyme, suggesting a possible role for NQO1 gene as an MLL-independent risk factor, in the leukemogenic process of this subtype of iALL. 相似文献
135.
Giuseppina Sandri Silvia Rossi Franca Ferrari Maria Cristina Bonferoni Corrado Muzzarelli Carla Caramella 《European journal of pharmaceutical sciences》2004,21(2-3):351-359
The aim of the present work was to evaluate the mucoadhesive and penetration enhancement properties via the buccal and vaginal mucosae of four different chitosan derivatives: 5-methyl-pyrrolidinone chitosan (MPC), two low molecular weight chitosans (DC1 and DC2) and a partially reacetylated chitosan (RC). Chitosan HCl was used as a reference. Polymer solutions (4% w/w) were prepared in media simulating the buccal (pH 6.4 buffer or water) and the vaginal (pH 5.0 buffer) environments and subjected to rheological characterization. Acyclovir was added to the polymer solutions at 5% (w/w) concentration. The mucoadhesive properties of the polymer solutions were measured using excised porcine cheek or vaginal mucosa and mucin dispersions to simulate the buccal or vaginal environments, respectively. Drug permeation and penetration tests were carried out using porcine cheek and vaginal mucosae as model membranes. Acyclovir aqueous suspensions prepared in pH 6.4 and 5.0 buffers were used as blanks. Drug release measurements were also carried out in the same conditions employed for the permeation and penetration tests. Methyl-pyrrolidinone chitosan shows the best mucoadhesive and penetration enhancement properties in both buccal and vaginal environments. The capability to enhance the permeation/penetration of acyclovir was decreased by partial depolymerization of chitosan and disappeared after partial reacetylation. 相似文献
136.
Spontaneous esophageal perforation (Boerhaave's syndrome) remains a difficult diagnostic and management problem with controversial recommendations regarding its treatment. The clinical manifestations of the disease are variable, and may be misleading, thus delaying accurate recognition. On the other hand, in view of the rapid onset of severe complications, particularly mediastinitis, a prompt diagnosis is essential to a better prognosis, successful operative outcome and potential survival. A case of spontaneous perforation of the thoracic esophagus penetrating the left pleural space treated within 4 hours from admission to the Emergency Room, with minimal surgical intervention is presented. Despite negative chest X-ray, a thoracic TC showed a small right sided effusion with left sided hydropneumothorax, and the definitive diagnosis was obtained by contrast study with a water soluble medium which showed the leak communicating freely with the left pleural space. The patient underwent repair by thoracic approach, the rupture was closed with a primary suture without flap reinforcement and the pleural space drained with the placement of single chest thoracostomy tube. The recovery was uneventful. The analysis of this case report and of the appropriate literature reveals that a poor prognosis is correlated with the time elapsed between the perforation and treatment. In conclusion the importance of an early aggressive surgical treatment for the Boerhaave's syndrome is emphasized, because any perforation treated more than 24 hours after the onset of symptoms, irrespective of the procedure used, is associated with a significantly higher morbility and mortality. 相似文献
137.
BACKGROUND: Reoperative neck exploration for hyperparathyroidism is often difficult even for experienced surgeons. Recent advances in preoperative and intraoperative localization techniques have improved successful resection rates. This prospective study evaluates the accuracy and clinical utility of intraoperative technetium 99m sestamibi scanning for localizing hyperfunctioning parathyroid tissue in reoperative neck explorations. PATIENTS AND METHODS: Eleven patients underwent reoperative neck exploration for hyperparathyroidism. Two patients had 3 prior neck explorations, 1 had 2 prior neck explorations, and 8 patients had 1 prior neck operation. Preoperative studies included sestamibi scintigraphy and ultrasound in all patients, magnetic resonance imaging in 4, computed tomography scan in 3, parathyroid arteriogram in 1, and selective venous sampling in 1. All patients underwent intraoperative technetium 99m sestamibi scanning and parathyroid hormone assay. RESULTS: Preoperative technetium 99m sestamibi scanning and ultrasound each successfully localized 7 of 11 hyperfunctioning glands (64%). Intraoperative technetium 99m sestamibi scanning correctly localized 10 of 11 hyperfunctioning glands (91%). Intraoperative parathyroid hormone assay confirmed successful excision of hyperfunctioning tissue in all 11 patients. Postoperatively, all 11 patients had low-normal or normal calcium levels. CONCLUSIONS: Intraoperative technetium 99m sestamibi correctly localized 91% of hyperfunctioning glands compared with 64% localization for preoperative technetium 99m sestamibi and preoperative ultrasound. Intraoperative technetium 99m sestamibi scanning and parathyroid hormone monitoring are useful in reoperative neck explorations for hyperparathyroidism. 相似文献
138.
The fused filament fabrication (FFF) process is widely used for producing prototypes and functional parts for diverse applications. While FFF is particularly attractive due to its cost-effectiveness, on the other hand, the fabricated parts have limitations in terms of large manufacturing time and reduced mechanical properties. The latter is strongly influenced by the fabrication process parameters, which affect the interlayer bonding and the adhesion between consecutive layers. Several works presented in the literature analysed the correlation between mechanical properties and process parameters. It was demonstrated that an increase in the fabrication feed rate causes slippage between filament and the feeding system, which leads to a decrease in the extruded material flow, and thus in part density. This work aims to investigate how the limitation of the slippage phenomenon affects the mechanical properties of parts fabricated using the FFF process. A prototype machine, equipped with a closed-loop control system on filament transport, was used to fabricate samples for tensile tests and dynamical mechanical analysis. Samples fabricated enabling the filament transport control showed an increase both in ultimate tensile strength and elongation at break for those fabricated with disabled control, whilst a decrease in stiffness was observed. In addition, the results showed that the use of a filament transport control system on a FFF machine increases the possibility of fabricating high value-added parts. 相似文献
139.
Fiorentini G Rossi S Bonechi F Vaira M De Simone M Dentico P Bernardeschi P Cantore M Guadagni S 《Journal of chemotherapy (Florence, Italy)》2004,16(3):293-297
Neuroendocrine tumors, particularly those of gastrointestinal tract origin, have a predisposition for metastasizing to the liver, causing parenchymal substitution and paraneoplastic syndrome. Lipiodol embolization combined with anticancer drugs is a recent tool in regional therapy. It has been proven that chemoembolization reduces tumor bulk and hormone levels, and that it palliates the symptoms of many patients with liver-dominant neuroendocrine metastases. Beginning in December 1988, ten patients with unresectable and chemotherapy-refractory liver metastatic neuroendocrine tumors were treated with chemoembolization based on a mixture of lipiodol, mitomycin, cisplatin, epirubicin, followed by gelfoam powder and contrast media. Toxicity encountered included: upper right quadrant pain requiring narcotics, elevation of lactate dehydrogenase, alkaline phosphatase, and transaminases. One patient had liver abscess and persistent fever for 2 weeks. We obtained two complete remissions lasting 12 and 34 months and 5 partial remissions. The median survival was 22 months. Four patients had urinary elevation of 5-hydroxyindolacetic acid (5-HIAA). They showed more than a 75% decrease in urinary secretion after treatment. In a patient with transplanted liver we noticed a partial response lasting 7 months. We conclude that chemoembolization will improve the clinical condition of a significant percentage of patients with liver metastases, that future therapy of carcinoid tumors will be based on specific tumor biology and that treatment will be customized for each individual patient combining the use of cytoreductive procedures including radiofrequency ablation, laser treatment and chemoembolization. 相似文献
140.
Unusual association of endometrial cancer and multiple myeloma 总被引:1,自引:1,他引:0
Buda G Orciuolo E Galimberti S Petrini M Maggini V Barale R Rossi AM 《Gynecologic oncology》2008,110(2):265-266