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81.
We present a case of refractory psychosis with prominent cognitive deficits in a patient with 'mega-cisterna magna', a congenital defect within the 'Dandy-Walker Complex' continuum. The 21-year-old female had a 3-year history of refractory psychotic symptoms despite adequate antipsychotic treatment. CT and MRI scans disclosed 'mega-cisterna magna'. Thorough neuropsychological testing recorded extensive deficits. Treatment with amisulpride 1200 mg/day resulted in a 30% decrease in PANSS score within 2 months. Then galantamine 8 mg/day was added and PANSS score decreased further by 27% within 2 weeks. Cognitive and social functioning was overall much improved. The effect was sustained in a 24 months follow-up. It is postulated that even a less extended cerebellar lesion, such as mega-cisterna magna, can be associated with psychosis, and in some cases with treatment refractoriness or cognitive dysfunction. Adjuvant galantamine may improve cognitive and psychosocial functioning in these patients.  相似文献   
82.
The involvement of striatal somatostatin receptors (sst1, sst2 and sst4) in locomotor activity was investigated. Male Sprague–Dawley rats, 280–350 g, received in the striatum bilateral infusions of saline, somatostatin, and selective sst1, sst2, and sst4 ligands. Spontaneous locomotor activity was recorded for 60 min. The involvement of excitatory amino acid receptors (AMPA and NMDA) on somatostatin’s actions was also examined. Western blot analysis was employed for the identification of somatostatin receptors in striatal membranes. Somatostatin, sst2 and sst4, but not sst1, selective ligands increased rat locomotor activity in a dose-dependent manner. Blockade of AMPA and NMDA receptors reversed somatostatin’s actions. In conclusion, striatal somatostatin receptor activation differentially influence rat locomotor activity, while glutamatergic actions underlie the behavioral actions of somatostatin.  相似文献   
83.
Spontaneous coronary artery dissection (SCAD) still is a rare cause of acute coronary syndrome. SCAD has been observed in three groups of patients: those with coronary atherosclerosis, peripartal women and idiopathic group. SCAD may be associated with some conditions. We report an unusual association: SCAD and pulmonary thromboembolism.  相似文献   
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85.
CONTEXT: Salivary cortisol levels during social challenge relate to adaptive functioning in children and adults. Low cortisol levels have been related to conduct problems and antisocial behavior. Although studies in rodents implicate early-life social experience in cortisol regulation, no studies with humans have examined the effects of an experimentally manipulated early-life social experience on cortisol regulation. OBJECTIVE: To examine the effects of experimental manipulations of social experience on cortisol response to a social challenge in preschoolers at risk for antisocial behavior. DESIGN: Randomized controlled trial. SETTING: Department of Child and Adolescent Psychiatry, New York University School of Medicine. PARTICIPANTS: Ninety-two preschool-age siblings of youths adjudicated for delinquent acts. Intervention Family-based intervention included 22 weekly group sessions for parents and preschoolers and 10 biweekly home visits conducted during a 6- to 8-month period. MAIN OUTCOME MEASURES: Salivary cortisol levels before and after a social challenge (entry into an unfamiliar peer group). RESULTS: Relative to controls, children in the intervention condition had increased cortisol levels in anticipation of the peer social challenge. Increases were relative to both preintervention cortisol levels during the challenge and cortisol levels in the home, which were not altered by the intervention. CONCLUSIONS: A family-based preventive intervention for children at high risk for antisocial behavior alters stress response in anticipation of a peer social challenge. The experimentally induced change in cortisol levels parallels patterns found in normally developing, low-risk children.  相似文献   
86.
We evaluated boronic acid (BA)-based methods for their ability to detect extended-spectrum β-lactamases (ESBLs) among clinical isolates of KPC-producing members of the Enterobacteriaceae family. A total of 155 isolates of Klebsiella pneumoniae (n = 141), Escherichia coli (n = 6), Enterobacter aerogenes (n = 6), and Klebsiella oxytoca (n = 2) genotypically confirmed to be KPC producers were analyzed. As many as 118 isolates harbored ESBLs (103 harbored SHV-type ESBLs, 13 harbored CTX-M-type ESBLs, and 2 harbored both SHV- and CTX-M-type ESBLs); the remaining 37 isolates were genotypically negative for ESBL production. The CLSI ESBL confirmatory test was positive for 79 of the 118 ESBL producers (sensitivity, 66.9%), while all 37 non-ESBL producers were negative (specificity, 100%). When a ≥5-mm increase in the zone diameter of either the cefotaxime (CTX)-clavulanate (CA) or the ceftazidime (CAZ)-CA disks containing BA compared with the zone diameter of the CTX or CAZ disks containing BA was considered to be a positive result for ESBL production, the method detected all 118 ESBL producers (sensitivity, 100%) and showed no false-positive results for non-ESBL producers (specificity, 100%). Double-disk synergy tests, in which disks of CTX, CAZ, aztreonam, or cefepime in combination with BA were placed at distances of 20, 25, and 30 mm (center to center) from a disk containing amoxicillin (amoxicilline)-clavulanate-BA, were able to detect 116 (98.3%), 101 (85.6%), and 28 (23.7%) of the ESBL-positive isolates, respectively; no false-positive results for non-ESBL-producing isolates were detected. Our results demonstrate that the modified CLSI ESBL confirmatory test with antibiotic disks containing BA is the most accurate phenotypic method for the detection of ESBLs in Enterobacteriaceae producing KPC carbapenemases.During the last decade, carbapenem resistance has emerged among clinical isolates of the Enterobacteriaceae family, and this is increasingly attributed to the production of β-lactamases capable of hydrolyzing carbapenems (23). Among these enzymes, a new type of Ambler class A β-lactamase, the Klebsiella pneumoniae carbapenemase (KPC), has been rapidly spreading among K. pneumoniae isolates and other Enterobacteriaceae in the northeastern regions of the United States and has now spread to several regions of North and South America, as well as in Israel, China, and Greece (2, 13, 16, 21).The current spread of KPC enzymes makes them a potential threat to currently available antibiotic-based treatments. These enzymes confer various levels of resistance to all β-lactams, including carbapenems, even though cefamycins and ceftazidime are only weakly hydrolyzed (15, 18). KPC-possessing strains frequently carry extended-spectrum β-lactamase (ESBL) genes (1, 3, 8, 13, 24), which could possibly contribute to the expression and dissemination of the β-lactam resistance trait (8, 18, 21). It should be also noted that KPCs and ESBLs are mostly plasmid-encoded determinants that can easily disseminate to other enterobacterial strains (3, 7, 15, 18, 26). Therefore, the phenotypic detection of ESBLs in KPC-producing isolates of the Enterobacteriaceae is of potential interest for epidemiological purposes as well as for limiting the spread of the underlying resistance mechanisms.The CLSI recommends a phenotypic confirmatory test for ESBL production that consists of measuring the growth-inhibitory zones around both cefotaxime (CTX) and ceftazidime (CAZ) disks with or without clavulanate (CA) for K. pneumoniae, Klebsiella oxytoca, Escherichia coli, and Proteus mirabilis (4). Different double-disk synergy tests (DDSTs) based on the synergy of amoxicillin (amoxicilline)-clavulanate (AMC) with extended-spectrum cephalosporins and aztreonam have also been extensively used for the detection of ESBLs (7). However, strategies for the laboratory identification of ESBLs need to be reviewed and adjusted as additional mechanisms of resistance to β-lactams coexist in enterobacterial strains (7). KPCs hydrolyze several β-lactam antibiotics, and hence, the presence of an ESBL can be masked by the expression of a KPC. Moreover, the weak inhibition of KPCs by the β-lactam inhibitors (15, 18, 30) may interfere with the interpretation of ESBL detection methods and KPC enzymes may be mistaken for ESBLs. Thus, there is a need to accurately detect ESBLs in the presence of coexisting KPC expression.Boronic acid (BA) compounds were recently reported to be reversible inhibitors of KPCs (6, 16, 27). In particular, we have shown that BA disk assays are considered positive for the detection of the KPC enzyme when the growth-inhibitory zone diameter around a meropenem, imipenem, or cefepime disk with phenylboronic acid is 5 mm or greater of the growth-inhibitory zone diameter around the disk containing meropenem or cefepime alone (27). The results of this study also showed that BA affected the activity of CAZ in ESBL-negative KPC-producing isolates but not in SHV ESBL-positive KPC-producing isolates, most likely due to the presence of the SHV ESBL, which is not restrained by BA (27). BA-based tests with disks of CAZ and CTX have also been successfully employed for the identification of ESBLs in AmpC producers (11, 25). These observations led us to design a modified CLSI ESBL confirmatory test using antibiotic disks containing BA as well as different DDSTs employing BA for the accurate detection of ESBLs in KPC-producing enterobacterial isolates.  相似文献   
87.
Strongyloidiasis is an opportunistic infection which may result in a fatal hyperinfection syndrome in immunocompromised patients. We report the case of a pulmonary infection with Strongyloides stercoralis in a 61‐year‐old male with a history of a long‐term administration of corticosteroids. Cytologic examination of a bronchial washing specimen, processed both as conventional and as Thin‐Prep smears, revealed an abundance of the typical larvae of Strongyloides stercoralis, amidst a cellular population comprising several acute inflammatory cells as well as bronchial epithelial cells with features of basal cell hyperplasia or regenerative atypia. To the best of our knowledge there is only one previous report describing Strongyloides stercoralis in thin‐layer smears, and there are no previous studies comparing its morphology in conventional and thin‐layer preparations. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
88.
Waldenström's macroglobulinemia is characterized by a protracted course in most patients and the median survival may be long. However, a subset of patients may present with more aggressive disease that is associated with short survival. In order to better characterize these “poor-risk” patients, we identified patients who died within 2 years from the initiation of front-line treatment. These patients were older and had more often features of aggressive disease, such as elevated LDH and low serum albumin than the standard-risk population. Furthermore, only a minority of poor-risk patient had a response to initial therapy. However, conventional clinical factors or even the lack on response could not adequately identify poor-risk patients, indicating the need for novel molecular or other markers that would be able to effectively recognize patients at greatest need for aggressive therapies.  相似文献   
89.
Reactions of thiosemicarbazones of 2-formyl and 2-acetyl pyridine and containing an azepane ring (hexamethyleneiminyl ring) incorporated at N(4)-position, HL(1) (1) and HL(2) (2) with platinum(II) afforded the complexes, [Pt(L(1))Cl] (3) and [Pt(L(2))Cl] (4). Characterization of the compounds was accomplished by means of elemental analysis and spectroscopic techniques NMR, UV-vis and IR spectroscopy. The single-crystal X-ray structure of complex [Pt(L(2))Cl] (4) shows that the ligand monoanion coordinates in a planar conformation to the metal via the pyridyl N atom, the imine-N atom, and thiolato S-atom. Compounds 1-4 have been evaluated for antiproliferative activity in vitro against three human cancer cell lines: MCF-7 (human breast cancer cell line), T24 (bladder cancer cell line), A-549 (non-small cell lung carcinoma) and a mouse L-929 (a fibroblast-like cell line cloned from strain L). Ligand 2 exhibited high activity as anticancer agent against all four cancer cell lines, while ligand 1 exhibited selectivity against MCF-7, L-929 cell lines and complex 4 against A-549, T-24 cancer cell lines. Also, the acute toxicity and antitumor activity were evaluated on leukemia P388-bearing mice. Complex 3 afforded five to six cures against leukemia P388. The in vivo results of the antitumor activity show the two platinum complexes as very effective chemotherapeutic antileukemic agents.  相似文献   
90.
Inhibitors of microsomal prostaglandin E synthase 1 (mPGES-1) are in the early phase of clinical development. Deletion of mPges-1 in mice confers analgesia, restrains atherogenesis, and fails to accelerate thrombogenesis, while suppressing prostaglandin E2 (PGE2), but increasing the biosynthesis of prostacyclin (PGI2). In low-density lipoprotein receptor–deficient (Ldlr–/–) mice, this last effect represents the dominant mechanism by which mPges-1 deletion restrains thrombogenesis, while suppression of PGE2 accounts for its antiatherogenic effect. However, the effect of mPges-1 depletion on blood pressure (BP) in this setting remains unknown. Here, we show that mPges-1 depletion significantly increased the BP response to salt loading in male Ldlr–/– mice, whereas, despite the direct vasodilator properties of PGI2, deletion of the I prostanoid receptor (Ipr) suppressed this response. Furthermore, combined deletion of the Ipr abrogated the exaggerated BP response in male mPges-1–/– mice. Interestingly, these unexpected BP phenotypes were not observed in female mice fed a high-salt diet (HSD). This is attributable to the protective effect of estrogen in Ldlr–/– mice and in Ipr–/– Ldlr–/– mice. Thus, estrogen compensates for a deficiency in PGI2 to maintain BP homeostasis in response to high salt in hyperlipidemic female mice. In male mice, by contrast, the augmented formation of atrial natriuretic peptide (ANP) plays a similar compensatory role, restraining hypertension and oxidant stress in the setting of Ipr depletion. Hence, men with hyperlipidemia on a HSD might be at risk of a hypertensive response to mPGES-1 inhibitors.  相似文献   
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