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81.
Abstract

Contribution to the Myxomycetes flora of Italy. — In this work 52 species, 20 of which new to Italy, are named. The specimens were collected in northern and central Italy.  相似文献   
82.
ABSTRACT

A glucose/mannose-binding lectin was isolated from seeds of Parkia discolor (Mimosoideae) using affinity chromatography on Sephadex G-100 gel. The protein presented a unique component in SDS-PAGE corresponding to a molecular mass of 58,000 Da, which is very similar to that of a closely related lectin from Parkia platycephala. Among the simple sugars tested, mannose was the best inhibitor, but biantennary glycans, containing the trimannoside core, present in N-glycoproteins, also seem to be powerful inhibitors of the haemagglutinating activity induced by the purified lectin. The protein was characterised by high content of glycine and proline and absence of cysteine. Rabbit antibodies, anti-P. platycephala seed lectin, recognised the P.discolor lectin. However, no cross-reaction was observed when a set of other legume lectins from sub-family Papilionoideae and others from families Moraceae and Euphorbiaceae were assayed with the Parkia lectins. This suggests that Parkia lectins comprise a new group of legume lectins exhibiting distinct characteristics.  相似文献   
83.
Heteropteran legs are very diverse within and among taxa, and such variation is frequently correlated with life habits. Structural modifications are commonly present in the legs of the Pentatomoidea but are poorly studied. Using scanning electron microscopy, the tibia and pretarsal microstructure of 82 species of Pentatomidae (Heteroptera), three species of Scutelleridae, and ten species of Thyreocoridae were described, focusing on the pretarsal structure, the foretibial apparatus, and the foretibial comb. The Pentatomidae, the Scutelleridae, and the Thyreocoridae have uniform pretarsal structures. Variation can be found in the length of the parempodial setae and in the shape of the parempodial projections. The foretibial combs of the Pentatomidae, the Thyreocoridae, and the Scutelleridae are described for the first time, and we have demonstrated that there is low structural variation in the foretibial comb complex of the studied species. The setae organization and distribution on the foretibial apparatus is uniform in the families studied. However, the Asopinae (Pentatomidae) bear a foretibial apparatus that is uniquely organized. The taxonomic and phylogenetic relevance of the pretarsal traits, the foretibial apparatus, and the foretibial comb are discussed.  相似文献   
84.
The analysis on nine inventories on the richness and diversity of galling herbivores in Brazil accounted for 806 gall systems occurring in 443 host-plant species from 74 plant families. This checklist of the Brazilian gall morphotypes proposes seven standardized morphotypes and five additional shapes that group the majority of the three-dimensional shapes reported in literature. Criteria are proposed to standardize the terminology, and a critical analysis is provided aiming to avoid possible inconsistencies in order to generate easily comparable data in future inventories. The morphotypes are herein catalogued in alphabetical order, accompanied by a conceptual definition, an illustration, and examples that best represent the shape. It is proposed that the inventories should present at least the (1) host-plant species, (2) galling herbivore species or its identification to the lowest possible taxonomic level, (3) host-plant galled organ and gall position, (4) gall morphotype, (5) gall color and registration of indumentum when present, (6) gall phenological and developmental data, (7) association with other trophic levels, and (8) additional information, such as dimension, and number of chamber(s).  相似文献   
85.
A review of the literature was performed to summarize current evidence regarding the efficacy of topical immunotherapy and chemotherapy for upper urinary tract urothelial cell carcinoma (UUT-UCC) in terms of post-treatment recurrence rates. A Medline database literature search was performed in March 2012 using the terms upper urinary tract, urothelial cancer, bacillus Calmette-Guérin (BCG), and mitomycin C. A total of 22 full-text articles were assessed for eligibility, and 19 studies reporting the outcomes of patients who underwent immunotherapy or chemotherapy with curative or adjuvant intent for UUT-UCC were chosen for quantitative analysis. Overall, the role of immunotherapy and chemotherapy for UUT-UCC is not firmly established. The most established practice is the treatment of carcinoma in situ (CIS) with BCG, even if a significant advantage has not yet been proven. The use of BCG as adjuvant therapy after complete resection of papillary UUT-UCC has been studied less extensively, even if recurrence rates are not significantly different than after the treatment of CIS. Only a few reports describe the use of mitomycin C, making it difficult to obtain significant evidence.Key words: Upper urinary tract, Urothelial cell carcinoma, Bacillus Calmette-Guérin, Mitomycin C, Chemotherapy, ImmunotherapyAccording to the 2011 update of the European Guidelines for the diagnosis and management of upper urinary tract urothelial cell carcinoma (UUT-UCC),1 urothelial carcinomas are the fourth most common tumors after prostate and breast cancer, lung cancer, and colorectal cancer. Bladder tumors account for 90% to 95% of urothelial carcinomas; UUT-UCC are relatively uncommon and account for only 5% to 10% of urothelial carcinomas. The annual incidence of UUT-UCC in Western countries is approximately one or two new cases per 100,000 inhabitants. Pyelocaliceal tumors are approximately twice as common as ureteral tumors. In 8% to 13% of cases, concurrent bladder cancer is present, and 60% of UUT-UCC are invasive at diagnosis, compared with only 15% of bladder tumors. This kind of carcinoma has a peak incidence in people in their 70s and 80s, with a higher prevalence in men.Radical nephroureterectomy (RNU) with excision of the bladder cuff represents the gold standard treatment for UUT-UCC, regardless of the location of the tumor in the upper urinary tract.1 Lymph node dissection associated with RNU is of therapeutic interest and allows for optimal staging of the disease.Conservative surgery for low-risk UUT-UCC allows for preservation of the upper urinary renal unit; conservative management can be considered in imperative cases (renal insufficiency, solitary functional kidney) or in elective cases (ie, when the contralateral kidney is functional) for low-grade, low-stage tumors. Endoscopic ablation can be considered if a flexible ureteroscope, laser generator, and pliers (pluck) for biopsies are available, if the patient is informed of the need for closer follow-up, and if a complete resection is advocated.Segmental ureteral resection with wide margins provides adequate pathologic specimens for definitive staging and grade analysis while also preserving the ipsilateral kidney. Segmental resection is possible for the treatment of low- and high-risk tumors of the distal ureter, whereas segmental resection of the iliac and lumbar ureter is associated with a greater failure rate. Open resection of tumors of the renal pelvis or calices has almost disappeared.Percutaneous management can be considered for low-grade or noninvasive UUT-UCC that are inaccessible or difficult to manage by ureteroscopy, even if a theoretical risk of seeding exits in the puncture tract and if perforations occur during the procedure.After conservative treatment of UUT-UCC or for the treatment of carcinoma in situ (CIS), the instillation of bacillus Calmette-Guérin (BCG) or mitomycin C (MMC) is technically feasible by means of a percutaneous nephrostomy or even through a ureteric stent.Different agents have been used for topical therapy, including BCG, MMC, epirubicine, and thiotepa. Topical chemotherapeutic agents can be administered after endoscopic management, whereas instillations of BCG need to be postponed until the urothelium heals to avoid systemic side effects.According to a recent review,2 topical therapy appears to be safe, although its efficacy is debatable. Complications from the administration of topical immunotherapy or chemotherapy can be avoided by maintaining low intracavitary pressures during administration. Renal function does not seem to be impaired after instillation of BCG or MMC.3 No systemic side effects result from perfusion with MMC, and persistent fever was reported in 5% of patients in combined major series after BCG administration; therefore, this side effect was resolved with appropriate antimicrobial therapy in all cases. Furthermore, up to 25% of patients may have granulomatous involvement of the urinary tract after BCG.This review summarizes current evidence about the efficacy of topical immunotherapy and chemotherapy in terms of post-treatment recurrence rates.  相似文献   
86.
87.
Ultrafiltration is an attractive downstream processing technique for concentrating enzymes and could be considered the primary step of purification. However, the efficiency of this process is often limited by protein fouling and shear-induced enzyme inactivation, which decreases permeate flux and results in the loss of enzyme activity. Although the rejection of phytase was higher than 99%, the loss of the enzyme activity was 14% during operation, indicating that the shear forces generated in the filter have significant influences on the enzyme activity. Two preparations using glycerol (25% and 35%, v/v) as a cryo-protecting agent at different temperatures were studied. The preparation containing 35% glycerol retained 70% of the initial enzyme activity at 70 °C after 1 h and had more than 3 and 6 months storage half-life at 29 °C and 4 °C, respectively.  相似文献   
88.

Aims/hypothesis

Changes in cellular cholesterol level may contribute to beta cell dysfunction. Islets from low density lipoprotein receptor knockout (LDLR−/−) mice have higher cholesterol content and secrete less insulin than wild-type (WT) mice. Here, we investigated the association between cholesterol content, insulin secretion and Ca2 + handling in these islets.

Methods

Isolated islets from both LDLR−/− and WT mice were used for measurements of insulin secretion (radioimmunoassay), cholesterol content (fluorimetric assay), cytosolic Ca2 + level (fura-2AM) and SNARE protein expression (VAMP-2, SNAP-25 and syntaxin-1A). Cholesterol was depleted by incubating the islets with increasing concentrations (0–10 mmol/l) of methyl-beta-cyclodextrin (MβCD).

Results

The first and second phases of glucose-stimulated insulin secretion (GSIS) were lower in LDLR−/− than in WT islets, paralleled by an impairment of Ca2 + handling in the former. SNAP-25 and VAMP-2, but not syntaxin-1A, were reduced in LDLR−/− compared with WT islets. Removal of excess cholesterol from LDLR−/− islets normalized glucose- and tolbutamide-induced insulin release. Glucose-stimulated Ca2 + handling was also normalized in cholesterol-depleted LDLR−/− islets. Cholesterol removal from WT islets by 0.1 and 1.0 mmol/l MβCD impaired both GSIS and Ca2 + handling. In addition, at 10 mmol/l MβCD WT islet showed a loss of membrane integrity and higher DNA fragmentation.

Conclusion

Abnormally high (LDLR−/− islets) or low cholesterol content (WT islets treated with MβCD) alters both GSIS and Ca2 + handling. Normalization of cholesterol improves Ca2 + handling and insulin secretion in LDLR−/− islets.  相似文献   
89.
The common bean (Phaseolus vulgaris L.) is the main source of protein and an important source of minerals in several countries around the world. Angular leaf spot, caused by the fungus Pseudocercospora griseola, is one of the major diseases of the common bean. In this work, we used two-dimensional gel electrophoresis and mass spectrometry to analyze alterations in the proteome of common bean leaves challenged with an incompatible race of P. griseola. Twenty-three differentially expressed proteins were detected in leaves of cultivar AND 277 collected at 12, 24 and 48 h after inoculation. The proteins were digested with trypsin and submitted to MALDI-TOF/TOF and MicrOTOF-Q electrospray mass spectrometry. Nineteen of them were identified upon MS/MS fragmentation. Most of these proteins are involved with amino acid metabolism, terpenoid metabolism, phenylpropanoid biosynthesis, antioxidant systems, vitamin and cofactor metabolism, plant–pathogen interaction, carbohydrate metabolism, photosynthesis, or genetic information processing, showing that the interaction in this pathosystem affects different genes from various metabolic pathways and processes.  相似文献   
90.
The family Prochilodontidae is considered a group with well conserved chromosomes characterized by their number, morphology and banding patterns. Thence, our study aimed at accomplishing a cytogenetic analysis with conventional methods (Giemsa staining, silver staining of the nucleolus organizer regions-AgNOR, and C-banding) and fluorescence in situ hybridization (FISH) with 18S and 5S ribosomal DNA probes in five species of the Prochilodus genus (Prochilodus argenteus, Prochilodus brevis, Prochilodus costatus, Prochilodus lineatus and Prochilodus nigricans) collected from different Brazilian hydrographic basins. The results revealed conservatism in chromosome number, morphology, AgNORs 18S and 5S rDNAs location and constitutive heterochromatin distribution patterns. The minor differences observed in this work, such as an Ag-NOR on a P. argenteus chromosome and a distinct C-banding pattern in P. lineatus, are not sufficient to question the conservatism described for this group. Future work using repetitive DNA sequences as probes for FISH will be interesting to further test the cytogenetic conservatism in Prochilodus.  相似文献   
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