Mutational Analysis of Quinolone Resistance Protein QnrB1

Alanine substitutions and selected deletions have been used to localize amino acids in QnrB essential for its protective activity. Essential amino acids are found at positions i and i⁻² in the pentapeptide repeat module and in the larger of two loops, where deletion of only a single amino acid compromises activity. Deletion of 10 amino acids at the N terminus is tolerated, but removal of 3 amino acids in the C-terminal dimerization unit destroys activity.     

Extending the communication phenotype associatedwith 22q11.2 Microdeletion Syndrome

This paper has three aims. The first is to describe and critically evaluate two recent studies from the authors' centre. Study one is a retrospective, consecutive series case note audit of 76 children aged 3.01 – 9.11 years of age, aimed at examining the age at which children with 22q11 deletion syndrome (22q11DS) are able to achieve oral pressure in their speech, and providing an overview of presentation. Study two is a pilot study to investigate the prevalence of dyspraxic features in a consecutive series of 21 school age children with 22q11DS, aged 4.0 – 8.11 years of age. The second aim is to discuss these studies within the context of a critical review of the current knowledge about 22q11 deletion syndrome. The third aim is to challenge some common thinking around the management of velopharyngeal dysfunction ( VPD) in 22q11DS. This discussion highlights that it is sometimes possible to investigate and treat palate function with good outcomes in the preschool years based on limited speech and language and investigations. Areas for future research are discussed. This paper further underlines the complexity of the communication profile in this population, with confirmation of the unique speech and language phenotype.     

γ-去氢骆驼蓬碱等咔啉类生物碱的辐射防护作用

γ- Harmine(Ⅰ),’harmine(Ⅱ )and harmaline(Ⅲ )were isolated from PeganumHarmala L.( Zygophylaceae).Tests were conducted with mice to detect whether γ- harmine( a newcompound), harmine,harmof(Ⅳ)and harmalol(Ⅴ) are effective radioprotective compounds againstγ-ray irradiation, Intraperitoneal injection of the hydrochlorides of the four alkaloids 50～80mg·kg^-1×1 in NIH male mice 30～45 minutes before 8.6～9. 7 Gy whole body ⁶⁰Co irradiationsignificantly increased the survival effects(1. 33～2. 61)and 30-day survivai rate in comparison withcontrol mice.The results indicatethat γ- harmine exhibited relatively good radioprotective effect.γ-harmine is the first alkaloid isolated from a plant having ptotective effects against whole-body lethal irradiation in mice.     

Magnetic resonance of the brain: the optimal screening technique

Magnetic resonance (MR) images and computed tomograms of 25 patients with head trauma were compared. MR proved to be superior in many ways for demonstrating extracerebral as well as intracerebral traumatic lesions. Isodense subdural hematomas, which present a diagnostic dilemma on CT images were clearly seen on MR, regardless of their varying CT densities. In a case of epidural hematoma, the dura mater was shown directly as nearly devoid of signal on MR. Direct coronal images provided excellent visualization of extracerebral collections along the peritentorial space and subtemporal area. In a patient with intracerebral hematoma, CT failed to demonstrate residual parenchymal changes in a 3-month follow-up study, but MR clearly depicted the abnormalities. The superiority of MR over CT was also well illustrated in a patient with post-traumatic osteomyelitis of the calvarium.     

Group I metabotropic glutamate receptors in spinal cord injury: roles in neuroprotection and the development of chronic central pain

Spinal cord injury (SCI) initiates a cascade of biochemical events that leads to an increase in extracellular excitatory amino acid (EAA) concentrations, which results in glutamate receptor-mediated excitotoxic events. An important division of these glutamate receptors is the metabotropic glutamate receptor (mGluR) class, which is divided into three groups. Of these three groups, group I (mGluR1 and mGluR5) activation can initiate a number of intracellular pathways that lead to increased extracellular EAA concentrations. To evaluate subtypes of group I mGluRs in SCI, we administered AIDA (group I antagonist), LY 367385 (mGluR1 specific antagonist), or MPEP (mGluR5 specific antagonist) by interspinal injection to adult male Sprague-Dawley rats (175-200 g) immediately following injury at T10 with an NYU impactor (12.5-mm drop, 10-g rod, 2 mm in diameter). AIDA- and LY 367385-treated subjects had improved locomotor scores and demonstrated an attenuation in the development of mechanical allodynia as measured by von Frey stimulation of the forelimbs; however, LY 367385 potentiated the development of thermal hyperalgesia. MPEP had no effect on locomotor recovery or mechanical allodynia, but attenuated the development of thermal hyperalgesia. AIDA and LY 367385 treatment resulted in a significant increase in tissue sparing compared to the vehicle-treated group at 4 weeks following SCI. These results suggest that mGluRs play an important role in EAA toxicity and have different acute pathophysiological roles following spinal cord injury.     

Briefing guide study: preoperative briefing and postoperative debriefing checklists in the Veterans Health Administration medical team training program

Background

The purpose of this study was to examine the outcomes of checklist-driven preoperative briefings and postoperative debriefings during the Veterans Health Administration (VHA) medical team training program.

Methods

A briefing score (1, never started; 2, started then discontinued; 3, maintained on original targeted cases; 4, expanded to other services; 5, briefing all cases, all services) was established at 10.1 ± .3 months after introduction of the checklist. Outcomes included antibiotic and deep venous thrombosis prophylaxis compliance rates before and after use of the checklist.

Results

Antibiotic (97.0% ± .1% vs 92.1% ± 1.5%; P = .01) and deep venous thrombosis (95.7% ± .8% vs 85.1% ± 4.6%; P = .05) prophylaxis compliance rates were higher after initiation of a surgical checklist.

Conclusions

Checklist-driven preoperative briefings and postoperative debriefings are associated with improvements in patient safety for surgical patients.     

Personal mastery attenuates the effect of caregiving stress on psychiatric morbidity

This study examined the protective effects of personal mastery on the relations between both objective and subjective stress and psychiatric morbidity in 79 spousal Alzheimer caregivers. Results indicated that with low mastery, the relations between patient problem behaviors and caregiver psychiatric symptoms was significant (t[71] = 2.03; p = 0.046). However, with high mastery, no significant association was found (t[71] = -0.76; p = 0.452). Similarly, the relations between role overload and psychiatric morbidity was significant when mastery was low (t[71] = 2.22; p = 0.029), but not high (t[71] = -1.49; p = 0.140). These results suggest that caregivers with a greater sense of personal mastery may be protected from the negative effects of caregiver stress.     

Contemporary outcomes after superficial femoral artery angioplasty and stenting: the influence of TASC classification and runoff score

OBJECTIVE: A recent randomized trial suggested nitinol self-expanding stents (SES) were associated with reduced restenosis rates compared with simple percutaneous transluminal angioplasty (PTA). We evaluated our results with superficial femoral artery (SFA) SES to determine whether TransAtlantic InterSociety Consensus (TASC) classification, indication for intervention, patient risk factors, or Society of Vascular Surgery (SVS) runoff score correlated with patency and clinical outcome, and to evaluate if bare nitinol stents or expanded polytetrafluoroethylene (ePTFE) covered stent placement adversely impacts the tibial artery runoff. METHODS: A total of 109 consecutive SFA stenting procedures (95 patients) at two university-affiliated hospitals from 2003 to 2006 were identified. Medical records, angiographic, and noninvasive studies were reviewed in detail. Patient demographics and risk factors were recorded. Procedural angiograms were classified according to TASC Criteria (I-2000 and II-2007 versions) and SVS runoff scores were determined in every patient; primary, primary-assisted, secondary patency, and limb salvage rates were calculated. Cox proportional hazard model was used to determine if indication, TASC classification, runoff score, and comorbidities affected outcome. RESULTS: Seventy-one patients (65%) underwent SES for claudication and 38 patients (35%) for critical limb ischemia (CLI). Average treatment length was 15.7 cm, average runoff score was 4.6. Overall 36-month primary, primary-assisted, and secondary rates were 52%, 64%, and 59%, respectively. Limb salvage was 75% in CLI patients. No limbs were lost following interventions in claudicants (mean follow-up 16 months). In 24 patients with stent occlusion, 15 underwent endovascular revision, only five (33%) ultimately remained patent (15.8 months after reintervention). In contrast, all nine reinterventions for in-stent stenosis remained patent (17.8 months). Of 24 patients who underwent 37 endovascular revisions for either occlusion or stenosis, eight (35%) had worsening of their runoff score (4.1 to 6.4). By Cox proportional hazards analysis, hypertension (hazard ratio [HR] 0.35), TASC D lesions (HR 5.5), and runoff score > 5 (HR 2.6) significantly affected primary patency. CONCLUSIONS: Self-expanding stents produce acceptable outcomes for treatment of SFA disease. Poorer patency rates are associated with TASC D lesions and poor initial runoff score; HTN was associated with improved patency rates. Stent occlusion and in-stent stenosis were not entirely benign; one-third of patients had deterioration of their tibial artery runoff. Future studies of SFA interventions need to stratify TASC classification and runoff score. Further evaluation of the long-term effects of SFA stenting on tibial runoff is needed.