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排序方式: 共有446条查询结果,搜索用时 15 毫秒
81.
82.
Bariohay B Roux JA Bonnet MS Dallaporta M Troadec JD 《Recent Patents on CNS Drug Discovery》2011,6(3):164-180
Obesity is one of the most important and disturbing global epidemic that affects humans, with more than 2 billion people overweight and 700 million obese predicted for 2015 by the World Health Organization. Obesity treatment represents then one of the most exciting challenges for the academic researchers and the pharmaceutical industry. But to date, this community failed to develop safe and effective treatments with a good risk/benefit profile. Indeed, most of the drugs previously used as anti-obesity agents have been withdrawn from the market for safety issues, and therapeutic options in form of a medication are currently very limited. This last decade however, new advances in our understanding of central pathways controlling food intake, body weight and energy homeostasis have led to the discovery of new molecular targets that could provide interesting options in the fight against obesity. This review aims to be an overview of the new patents exploiting the anorexigenic properties of the central catabolic pathways or aimed at blocking the orexigenic effects of the anabolic pathways, in the hope to develop new anti-obesity drugs. 相似文献
83.
Sala L Mirabel-Sarron C Gorwood P Pham-Scottez A Blanchet A Rouillon F 《Eating and weight disorders : EWD》2011,16(4):e280-e284
We assessed whether re-nutrition and weight gain have an influence on comorbid depression and anxiety in patients hospitalised for chronic eating disorders (ED). Seventy-five inpatients agreed to participate by completing the Eating Attitudes Test (EAT-40), the Beck Depression Inventory (BDI-13), and the State-Trait Anxiety Inventory (STAI-Y) before, during and after three months of treatment. Patients suffering from either anorexia nervosa or bulimia nervosa successfully regained weight during treatment. This weight gain was accompanied by statistically significant reductions in ED symptoms. Anxiety and, to a lesser extent, depressive symptoms diminished, but remained at pathological levels, with between diagnostic subtype differences. Improvement of depressive (r=0.77) and anxiety (r=0.64) levels were significantly (p<0.001) and positively correlated with the reduction of eating attitudes (EAT). These results are discussed in the context of re-orienting the therapeutic strategies aimed at reducing emotional suffering in patients with ED. 相似文献
84.
85.
86.
Jean-Baptiste Charrier Isabelle Rouillon Gilles Roger Fran?oise Denoyelle Sylvie Collon Eréa No?l Garabedian 《The Cleft palate-craniofacial journal》2006,43(4):488-491
OBJECTIVES: Congenital sinuses or fistulas of the lip are uncommon malformations, yet true medial upper-lip fistulas (MULFs) are extremely rare. We present a new case of congenital upper-lip fistula located in the midline of the philtrum of an 8-month-old girl. INTERVENTION: Complete surgical removal was performed with a combined extra- and intraoral approach. Histological examination revealed that the fistula was lined by squamous epithelium with sebaceous and mucous glands and hair follicles. RESULTS: Several embryological hypotheses have been proposed concerning these anomalies. This article reexamines and discusses major embryological theories on pathogenesis of sinuses or fistulas of the upper lip. We propose that early ectodermal inclusion events may occur in the medial fusion area during formation of the intermaxillary process. This embryological approach is highly concordant with our recent hypothesis on nasal dermoid sinus cysts (NDSCs) pathogenesis, in which we proposed an embryological hypothesis with early ectodermal inclusion phenomenon in the midline suture area to explain NDSCs pathogenesis. CONCLUSIONS: Common early ectodermal inclusion phenomena could be involved in both NDSCs and MULFs pathogenesis. 相似文献
87.
This study described the imaging features of a distinctive pattern of biopsy-proven benign non-traumatic vertebral collapse
(VC) that can mimic malignancy. Among 240 patients referred with painful VC over a 10-year period, we retrospectively selected
15 cases of benign VC which simulated malignancy, due to cortical bone destruction on radiographs. The diagnosis of benign
origin was documented by percutaneous biopsy and 12-months of follow-up. Radiographs, CT and MR images of the spine were reviewed.
Findings suggestive of malignancy included destruction involving the anterolateral cortex, posterior cortex and pedicles of
the vertebral body (46%,15% and 15% respectively) at CT, epidural soft-tissue masses on CT (23%) and MR images (21%), and
diffuse low signal-intensity (SI) of the vertebral body (50%) and pedicles (79%) on T1-weighted images. Features suggestive
of a benign origin included an intravertebral vacuum phenomenon on radiographs and CT (13%), fracture lines within the vertebral
body (92%) or pedicles (62%) at CT and presence an intravertebral area of high SI on T2-weighted images (93%). Benign non-traumatic
osteolytic VC can simulate malignancy on radiographs. The features, above mentioned on CT and MR suggestive of a benign VC,
are useful in interpreting biopsy results of such lesions and avoiding unnecessary repeat biopsy. 相似文献
88.
CT-guided percutaneous laser photocoagulation of osteoid osteomas of the hands and feet 总被引:1,自引:0,他引:1
Percutaneous local ablation of osteoid osteoma has largely replaced surgery, except in the small bones of the hands and feet.
The objective of this study was to describe the technical specificities and results of computed tomography (CT)-guided percutaneous
laser photocoagulation in 15 patients with osteoid osteomas of the hands and feet. We retrospectively examined the medical
charts of the 15 patients who were treated with CT-guided percutaneous laser photocoagulation therapy at our institution between
1994 and 2004. The 15 patients had a mean age of 24.33 years. None of them had received any prior surgical or percutaneous
treatment for the osteoid osteoma. The follow-up period was 24 to 96 months (mean, 49.93). The pain resolved completely within
1 week. Fourteen patients remained symptom-free throughout the follow-up period; the remaining patient experienced a recurrence
of pain after 24 months, underwent a second laser photocoagulation procedure, and was symptom-free at last follow-up 45 months
later. No adverse events related to the procedure or to the location of the tumor in the hand or the foot were recorded. CT-guided
percutaneous laser photocoagulation is an alternative to surgery for the treatment of osteoid osteomas of the hands and feet. 相似文献
89.
Laurent Poirel Jean-Denis Docquier Filomena De Luca Annemie Verlinde Louis Ide Gian Maria Rossolini Patrice Nordmann 《Antimicrobial agents and chemotherapy》2010,54(1):533-535
A Pseudomonas aeruginosa isolate recovered in Belgium produced a novel extended-spectrum ß-lactamase, BEL-2, differing from BEL-1 by a single Leu162Phe substitution. That modification significantly altered the kinetic properties of the enzyme, increasing its affinity for expanded-spectrum cephalosporins. The blaBEL-2 gene was identified from a P. aeruginosa isolate clonally related to another blaBEL-1-positive isolate.Extended-spectrum ß-lactamases (ESBLs), such as TEM, SHV, PER, VEB, GES, and more recently, CTX-M variants, are reported increasingly to be found in Pseudomonas aeruginosa in various areas (1, 2, 7, 8, 10-12, 15, 17, 21, 23, 27, 28, 30). The BEL-1 ß-lactamase, distantly related to other ESBLs, was identified from a P. aeruginosa isolate from Roeselare, Belgium, which interestingly shows resistance to ticarcillin and ceftazidime but only reduced susceptibility to piperacillin, cefepime, cefpirome, and aztreonam (24). The blaBEL-1 determinant was found as a gene cassette in the chromosome-borne class 1 integron, In120, that includes other resistance genes (aacA4, aadA5, and smr2) and that was part of a Tn1404-type transposon structure (24). Very recently, Bogaerts et al. (5) reported on the diffusion of BEL-1-producing isolates in various hospital centers of Belgium and also found that BEL-1 could be associated with other relevant β-lactamases, such as the VIM-1 metallo-β-lactamase (5).P. aeruginosa isolate 531 (this study) was recovered from a urine sample of a patient hospitalized in Roeselare, Belgium, in February 2007 for pneumonia and was resistant to all β-lactams but imipenem (Table (Table1).1). A synergy between aztreonam or ceftazidime and clavulanic acid-containing disks suggested the synthesis of an ESBL (19). PCR followed by sequencing using ESBL gene-specific primers (24) identified a novel gene encoding BEL-2, which differs from BEL-1 by a single amino acid substitution (Leu to Phe at Ambler position 162) (3). Transfer of a ß-lactam resistance marker from P. aeruginosa 531 to Escherichia coli or to P. aeruginosa reference strains was unsuccessful by either conjugation or transformation (25). Plasmid extraction performed as described previously (14) did not identify any plasmid, suggesting a chromosomal location of the blaBEL-2-like gene in P. aeruginosa 531. A pulsed-field gel electrophoresis (PFGE) analysis (4) showed that isolates 531 (BEL-2 positive) and 51170 (BEL-1 positive), recovered from the same geographical area, were clonally related. A PCR mapping approach confirmed the presence of a class 1 integron whose structure was identical to that of In120 of P. aeruginosa 51170 (24) and identified an identical structure in P. aeruginosa 531 (data not shown). Overall, these data suggest that the blaBEL-2 sequence likely resulted from a mutational event that had occurred in In120-carrying P. aeruginosa strains.
Open in a separate windowaMICs of β-lactams for P. aeruginosa 531 and 51170 clinical isolates, producing ESBLs BEL-2 and BEL-1, respectively, E. coli TOP10 harboring recombinant plasmid pSB-2 expressing BEL-2, E. coli TOP10 harboring recombinant plasmid pSB-1 expressing BEL-1, and the E. coli TOP10 reference strain.bCLA, clavulanic acid at a fixed concentration of 4 μg/ml; TZB, tazobactam at a fixed concentration of 4 μg/ml.In order to compare the contributions of BEL-1 and BEL-2 to ß-lactam resistance, the corresponding genes (amplified using primers PreBEL-A [5′-AGACGTAAGCCTATAATCTC] and PreBEL-B [5′-GCGAATTGTTAGACGTATG]) were cloned in the pCR-BluntII-TOPO vector (Invitrogen, Cergy-Pontoise, France) and subsequently introduced into E. coli TOP10, giving rise to recombinant strains E. coli TOP10(pSB-1) and E. coli TOP10(pSB-2), producing BEL-1 and BEL-2, respectively. MICs of ß-lactams were determined by solid agar dilutions following the guidelines of the CLSI (9). E. coli TOP10(pSB-2) had MICs of piperacillin, cephalothin, and cefuroxime that were lower than those of E. coli TOP10(pSB-1), but its cefotaxime, ceftazidime, ceftriaxone, and cefepime MICs were higher than those of TOP10(pSB-1), while MICs of carbapenems were the same (Table (Table11).E. coli TOP10(pSB-2) produced a ß-lactamase with a pI value of 7.1 (identical to that of BEL-1) (18). Approximately 1.5 mg of BEL-2 was purified (>95% as estimated by SDS-PAGE analysis; data not shown) from an E. coli MCT236(pET-BEL-2) crude extract by using a two-step chromatography process (an anion exchange at pH 7.5 using a Q Sepharose Fast Flow column followed by a cation exchange at pH 6.2 using a 1-ml Resource S column). (The specific activity was 8,800 nmol/min·mg of protein with 100 μM of cephalothin as the substrate, purified 95-fold.) BEL-2 had a broad-spectrum hydrolysis profile, including penicillins and expanded-spectrum cephalosporins but not cephamycins and carbapenems (Table (Table2).2). BEL-2 overall showed higher catalytic efficiencies (kcat/Km) than BEL-1 for aztreonam and most oxyiminocephalosporins (cefotaxime, ceftazidime, ceftriaxone, and cefepime but not cefuroxime). This was due to a significant alteration of the Km values for these substrates with BEL-2, which were decreased relative to those of BEL-1 by 300-fold (ceftriaxone) to up to three orders of magnitude (ceftazidime) (Table (Table2).2). Interestingly, a decrease of the Km value was also observed with all the other substrates (though the variation was less important), likely reflecting a modification of the active site structure and thus substrate recognition. Overall, BEL-2 kcat values were also lower but to a lesser extent (Table (Table2).2). The values of catalytic efficiency toward expanded-spectrum cephalosporins for BEL-2 may explain the higher MICs observed for the BEL-2-producing recombinant E. coli strains and P. aeruginosa clinical isolate. Position 162 is located at the beginning of the Ω loop, which bears the functionally important Glu166 residue, which is conserved in class A enzymes, and where mutations conferring extended-spectrum properties have been extensively reported in natural TEM and SHV variants (13). The presence of a bulky Phe residue in BEL-2 might modify the orientation of the Ω loop and the overall geometry of the active site. The further extension of the substrate profile as a consequence of a single substitution in the Ω loop observed with the BEL-2 variant may parallel that of other enzymes, e.g., CTX-M-19 (CTX-M-14 Pro167Ser variant) (26) or GES-2 (GES-1 Gly170Asn variant) (28). Inhibition studies showed that BEL-2 and BEL-1 are similarly inhibited by clavulanic acid, tazobactam, and sulbactam (50% inhibitory concentrations of 0.1, 2, and 3 μM, respectively).
Open in a separate windowaStandard deviations were below 15%. ND, not determinable, due to the initial rate of hydrolysis being too low. 相似文献
TABLE 1.
MICs of β-lactamsaβ-Lactam(s)b | MIC (μg/ml) | ||||
---|---|---|---|---|---|
P. aeruginosa 531 | P. aeruginosa 51170 | E. coli TOP10 (pSB-2) (BEL-2) | E. coli TOP10 (pSB-1) (BEL-1) | E. coli TOP10 | |
Amoxicillin | >512 | >512 | >512 | >512 | 4 |
Amoxicillin and CLA | >512 | >512 | 64 | 64 | 4 |
Ticarcillin | >512 | >512 | >512 | >512 | 4 |
Ticarcillin and CLA | >512 | 128 | 64 | 64 | 4 |
Piperacillin | 16 | 16 | 32 | 128 | 1 |
Piperacillin and TZB | 8 | 8 | 8 | 32 | 1 |
Cephalothin | >512 | >512 | 256 | 256 | 2 |
Cefuroxime | >512 | >512 | 32 | 128 | 2 |
Cefoxitin | 512 | 512 | 2 | 2 | 2 |
Ceftazidime | 256 | 32 | 128 | 16 | 0.06 |
Cefotaxime | 256 | 32 | 32 | 4 | 0.12 |
Cefepime | 16 | 4 | 1 | 0.25 | 0.06 |
Cefpirome | 64 | 16 | 0.5 | 0.25 | 0.06 |
Aztreonam | 64 | 32 | 16 | 16 | 0.12 |
Imipenem | 1 | 1 | 0.12 | 0.12 | 0.12 |
TABLE 2.
Kinetic parameters of purified ß-lactamase BEL-2, in comparison with previously reported values of BEL-1 (22)aß-Lactam | BEL-2 | BEL-1 | ||||
---|---|---|---|---|---|---|
kcat (s−1) | Km (μM) | kcat/Km (mM−1· s−1) | kcat (s−1) | Km (μM) | kcat/Km (mM−1· s−1) | |
Benzylpenicillin | 1.2 | 4 | 300 | 3 | 20 | 150 |
Piperacillin | 1.1 | 0.3 | 3,700 | 2 | 15 | 130 |
Cephalothin | 4.3 | 2 | 2,200 | 150 | 280 | 540 |
Cephaloridine | 1.2 | 8 | 150 | 30 | 130 | 230 |
Cefoxitin | <0.01 | ND | ND | <0.01 | ND | ND |
Cefuroxime | 0.88 | 12 | 73 | 10 | 40 | 250 |
Ceftriaxone | 0.2 | 0.1 | 2,000 | 25 | 30 | 830 |
Cefotaxime | 0.13 | 0.45 | 290 | 30 | 250 | 120 |
Ceftazidime | 0.03 | 0.64 | 47 | >1.5 | >700 | ND |
Cefepime | 0.003 | 0.3 | 10 | 1 | 150 | 7 |
Aztreonam | 0.1 | 0.36 | 280 | 10 | 100 | 100 |
Imipenem | <0.01 | ND | ND | <0.01 | ND | ND |
90.