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71.
72.
Multifunctional microcapsules for pancreatic islet cell entrapment: design,preparation and in vitro characterization 总被引:2,自引:0,他引:2
Luca G Basta G Calafiore R Rossi C Giovagnoli S Esposito E Nastruzzi C 《Biomaterials》2003,24(18):3101-3114
Great advances in cell transplantation have been made, including the recent, remarkable success in pancreatic islet transplantation for the treatment of type 1 diabetes mellitus. Unfortunately, the transplanted cells are very susceptible to oxidative stress that cause severe damage to either allo- or xenogeneic islets upon graft in diabetic patients. Consequently, the transplanted islet functional life span is significantly shortened. The aim of this study was to examine the possible effects of antioxidants on in vitro cultured adult rat islets, and to evaluate the effects of a prolonged-release formulation, in form of cellulose acetate (CA) microspheres, on Vitamin D(3) activity. Isolated rat islets, both free and entrapped in microspheres were treated with Vitamin D(3). The effects of the vitamin were studied at 3, 6 and 9 days of in vitro cell culture. According to insulin secretory patterns, treatment with Vitamin D(3) of both free and CA entrapped microspheres, increased the insulin output as compared to untreated controls. Such positive effects were confirmed under islet static incubation with glucose at day 6. These results suggest that pancreatic islets can be advantageously treated with anti-oxidising vitamins before implantation, and speculatively, with the help of special delivery systems, throughout the islet cell life span, in the post-transplant time period. 相似文献
73.
Monica Rossi Enzo Ricci Luca Colantoni Giuliana Galluzzi Roberto Frusciante Pietro A Tonali Luciano Felicetti 《BMC medical genetics》2007,8(1):8
Background
The homologous 4q and 10q subtelomeric regions include two distinctive polymorphic arrays of 3.3 kb repeats, named D4Z4. An additional BlnI restriction site on the 10q-type sequence allows to distinguish the chromosomal origin of the repeats. Reduction in the number of D4Z4 repeats below a threshold of 10 at the 4q locus is tightly linked to Facioscapulohumeral Muscular Dystrophy (FSHD), while similar contractions at 10q locus, are not pathogenic. Sequence variations due to the presence of BlnI-sensitive repeats (10q-type) on chromosome 4 or viceversa of BlnI-resistant repeats (4q-type) on chromosome 10 are observed in both alleles. 相似文献74.
Helicobacter pylori infection affects eosinophilic cationic protein in the gastric juice of patients with idiopathic chronic urticaria 总被引:6,自引:0,他引:6
Ojetti V Armuzzi A De Luca A Nucera E Franceschi F Candelli M Zannoni GF Danese S Di Caro S Vastola M Schiavino D Gasbarrini G Patriarca G Pola P Gasbarrini A 《International archives of allergy and immunology》2001,125(1):66-72
BACKGROUND: Helicobacter pylori, the main cause of gastritis and peptic ulcer, has been associated with idiopathic chronic urticaria (ICU), an immunological skin disorder of unknown origin. Eosinophilic cationic protein (ECP) is a cytotoxic molecule secreted by the activated eosinophils involved in the pathogenesis of ICU. We assessed serum/gastric juice ECP levels and gastric mucosal eosinophil infiltration in ICU patients infected or not with H. pylori and evaluated the modification after bacterium eradication. METHODS: 33 patients with ICU and 25 dyspeptic controls underwent upper gastrointestinal endoscopy for histological evaluation and assessment of H. pylori infection. One-week triple therapy was given to H. pylori-positive patients. Serum and gastric juice ECP levels, eosinophil infiltration from gastric mucosal sections and urticaria symptoms were evaluated in all patients at enrollment and 8 weeks after eradication. RESULTS: 19 of 33 (57%) ICU patients and 16 of 25 (64%) controls were found to be infected with H. pylori. Serum ECP was significantly higher in ICU patients compared to controls, regardless of infectious status. Gastric juice ECP and gastric eosinophil infiltration were significantly higher in infected ICU patients when compared both to uninfected ICU patients and controls. H. pylori eradication determined a significant decrease in gastric juice ECP and gastric eosinophil infiltration only in ICU patients. Moreover, a total or partial remission of urticaria symptoms was observed only in ICU patients in whom the bacterium was eradicated. CONCLUSIONS: Although H. pylori infection affects gastric juice ECP and eosinophil infiltration of ICU patients, the role of the bacterium in the pathogenesis of this skin disorder still remains uncertain. 相似文献
75.
Murri R Ammassari A Pezzotti P Cingolani A De Luca A Pallavicini F Grillo R Antinori A 《Journal of acquired immune deficiency syndromes (1999)》2001,27(1):49-55
We assessed the incidence and determinants of bacteremia, pneumonia, and sinusitis/otitis in HIV-positive people receiving cotrimoxazole (CTX) or dapsone-pyrimethamine (DP) for primary prophylaxis of Pneumocystis carinii pneumonia (PCP) and toxoplasmic encephalitis (TE) within a randomized clinical trial. In total, 244 patients were randomized: 122 were assigned to CTX and 122 to DP. In the cohort, 22 bacteremia, 63 pneumonia, and 39 sinusitis/otitis cases were observed. Incidence rates of bacteremia, pneumonia, and sinusitis/otitis as well as the 2-year probability of remaining free from any bacterial infection were not significantly different between the two groups. At multivariate analysis, the risks of developing bacteremia and pneumonia were found to be independently increased by the use of a central venous catheter (hazard ratio [HR], 4.48; p <.05 and HR, 4.13; p <.01, respectively) and by hospitalization (HR, 28.82; p <.05 and HR, 10.15; p <.05, respectively). In conclusion, CTX at the dosage employed for primary PCP/TE prophylaxis does not seem to protect against bacterial infections more than second-line DP. 相似文献
76.
77.
A one-year follow-up on the effects of raloxifene on thyroid function in postmenopausal women 总被引:5,自引:0,他引:5
Ceresini G Morganti S Rebecchi I Bertone L Ceda GP Bacchi-Modena A Sgarabotto M Baldini M Ablondi F Valenti G Braverman LE 《Menopause (New York, N.Y.)》2004,11(2):176-179
OBJECTIVE: Estrogens increase serum thyroxine-binding globulin (TBG) and total thyroxine (TT4) concentrations. Serum free thyroxine (FT4) concentrations, however, remain normal. Raloxifene (RAL) is a selective estrogen receptor modulator used to treat postmenopausal osteoporosis. Data on the long-term effects of RAL on thyroid physiology are scanty. We evaluated the effects of RAL administration for 1 year on thyroid function in osteopenic, postmenopausal women. DESIGN: Fifty osteopenic, postmenopausal women were randomly assigned to receive either RAL (60 mg/day, n = 25) or placebo (PL, n = 25) for 1 year, in a double-blind study. Measurements of serum TBG, TT4, FT4, thyroid-stimulating hormone (TSH), thyroid hormone-binding ratio (THBR), FT4 index (FT4-I) and TT4/TBG ratio were carried out at baseline and after 4 and 12 months of therapy. RESULTS: Baseline values were similar in both treatment groups. Serum TBG concentrations were increased during RAL treatment from baseline values of 29.60 +/- 0.9 microg/mL to 31.45 +/- 1.33 and 32.34 +/- 1.37 microg/mL at 4 months and 1 year, respectively (P < 0.05, baseline v 1-year values) but were unchanged during PL treatment. A small, insignificant increase in TT4 and TSH concentrations occurred in the RAL group and no changes in the PL group. All other values were unchanged during either treatment. CONCLUSIONS: These results demonstrate that RAL significantly increased serum TBG levels, but the changes were small and not accompanied by changes in FT4-I, FT4, or TSH concentrations, suggesting that long-term RAL treatment is unlikely to clinically affect the thyroid status in euthyroid, postmenopausal women. 相似文献
78.
Ludovico Dipineto Antonio Gargiulo Luigi M. De Luca Bossa Laura Rinaldi Luca Borrelli Lucia F. Menna 《Avian pathology》2008,37(5):507-508
The present study was undertaken with the aim to evaluate the prevalence of thermotolerant Campylobacter spp. in living pheasants in Italy. To achieve this goal, a total of 240 living pheasants, equally shared between female and male birds, were examined. Thermotolerant Campylobacter spp. was isolated in 104 out of 204 (43.3%) living pheasants analysed. Campylobacter coli (100%) and Campylobacter jejuni (13.5%) were identified by polymerase chain reaction. Adult pheasants showed a significantly higher prevalence value (P < 0.05) than younger pheasants. 相似文献
79.
Dr. G. Barresi C. Inferrera F. De Luca 《Virchows Archiv : an international journal of pathology》1978,380(4):341-348
Summary The authors have studied the pancreas of a premature female infant born to a diabetic mother. The findings included a peri-insular eosinophilic leucocyte infiltration, macropolinesia and a marked increase in B cells. In the exocrime parenchyma small B cells aggregates were also observed. B cells contained voluminous hypercromatic muclei and degranulated cytoplasm. Morphometric data demonstrated an increase in islet tissue. These morphological findings are indicative of excessive insulin secretion. The presence of eosinophilic leucocytes in pancreatic tissue and the pathogenic mechanism involved are discussed. 相似文献
80.
Heterogeneous pattern of chromosomal breakpoints involving the MYC locus in multiple myeloma 总被引:2,自引:0,他引:2
Fabris S Storlazzi CT Baldini L Nobili L Lombardi L Maiolo AT Rocchi M Neri A 《Genes, chromosomes & cancer》2003,37(3):261-269
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM. 相似文献