药物在室内自然光照射下的贮存期预测方法研究

以己酸孕酮注射液为例,研究了药物在自然光和不同灯光照射下的含量变化规律,预测了药物在室内自然光照射下的贮存期。找出了不同光源对药物稳定性影响的等效数量关系,使在今后的研究中可以用灯光为光源预测药物在室内自然光照射下的贮存期。己酸孕酮注射液在光照试验中含量变化服从零级反应规律:C=C₀-K(Et),在室内自然光照射下的贮存期约为1.9年。     

Comparison of weight loss achieved after laparoscopic adjustable gastric banding between Afro-Caribbean,Caucasian and South Asian adult female patients in a London bariatric centre

Introduction

It has been shown that following laparoscopic adjustable gastric banding (LAGB) procedures, Afro-Caribbeans achieve poorer weight loss compared with Caucasians. The reasons for this are multifactorial. However, studies have been based on mainly female patients from the US and none to date have been from the UK. Furthermore, South Asians have not previously been compared. The aim of this study was to compare excess weight loss percentage (%EWL) outcomes up to five years following LAGB in Afro-Caribbean, Caucasian and South Asian females in a London-based teaching hospital.

Methods

An analysis was carried out of prospectively collected data of female patients aged ≥16 years of Afro-Caribbean, Caucasian or South Asian origin who underwent LAGB between October 2000 and December 2011. Data included demographics, co-morbidities and anthropometrics.

Results

Overall, 596 females underwent LAGB; 316 Caucasians (53.0%), 64 Afro-Caribbeans (10.8%) and 27 South Asians (4.5%) formed the majority of those who disclosed ethnicities. Age and initial body mass index (BMI) were comparable between Afro-Caribbeans and Caucasians (mean BMI: 47.3kg/m² [standard deviation [SD]: 7.5kg/m², range: 37.0–78.3kg/m²] vs 45.8kg/m² [SD: 7.1kg/m², range: 24.7–79.8kg/m²], p=0.225). A non-significant trend suggested less %EWL in Afro-Caribbeans than in Caucasians at 6 months, and at 1, 2, 3, 4 and 5 years (21.4% vs 24.4%, p=0.26; 27.4% vs 31.3%, p=0.27; 33.0% vs 36.8%, p=0.15; 39.0% vs 45.8%, p=0.14; 34.2% vs 45.3%, p=0.16; 37.1% vs 47.6%, p=0.67). South Asians and Caucasians had a similar age and preoperative BMI (mean BMI: 43.6kg/m² [range: 32.5–59.1kg/m²] vs 45.8kg/m² [range: 24.7–79.8kg/m²], p=0.08). The %EWL was greatest at three and four years among South Asians although numbers were small (n=4 and n=3 respectively).

Conclusions

A non-significant trend suggests poorer weight loss outcomes in Afro-Caribbeans compared with Caucasians in our cohort. Discussion of realistic weight loss outcomes as well as enhanced follow-up and dietary modifications are required for Afro-Caribbean patients. Low numbers prevent definitive conclusions regarding South Asians. Multicentre studies across England are required to better define any differences between ethnicities.     

Acute and long-term effects of massive balloon dilation on the aortic wall and vasa vasorum

To investigate the acute and long-term effects on the vasa vasorum after massive overdilation, canine aortic segments were dilated with Gruentzig balloon catheters to more than 100% over normal size. In the acute study, the significant lumen increase was the result of intimal and medial rupture with stretching and thinning of the adventitia. In these areas, the vasa vasorum were stretched and severed, causing adventitial hemorrhage. In the chronic study, areas of previous subtotal wall rupture with adventitial thinning were repaired by scar tissue. This repair included formation of a neomedia, hyperplasia of the adventitia, and proliferation of the vasa vasorum. No progression of luminal dilatation was seen. This study showed that in subtotal aortic wall rupture, even a severely damaged adventitia is capable of preserving the lumen from further dilatation and rupture until healing. Blood flow to the damaged vessel wall was reestablished by revascularization via capillary budding in the aortic wall.     

Systematic review and stratified meta-analysis of the efficacy of carnosine in animal models of ischemic stroke

Carnosine is a naturally occurring pleotropic dipeptide which influences multiple deleterious mechanisms that are activated during stroke. Numerous published studies have reported that carnosine has robust efficacy in ischemic stroke models. To further evaluate these data, we have conducted a systematic review and meta-analysis of published studies. We included publications describing in vivo models of ischemic stroke where the neuroprotective efficacy of carnosine was being evaluated through the reporting of infarct volume and/or neurological score as outcomes. Overall efficacy was evaluated using weighted mean difference random effects meta-analysis. We also evaluated for study quality and publication bias. We identified eight publications that met our inclusion criteria describing a total of 29 comparisons and 454 animals. Overall methodological quality of studies was moderate (median = 4/9). Carnosine reduced infarct volume by 29.4% (95% confidence interval (CI), 24.0% to 34.9%; 29 comparisons). A clear dose-response effect was observed, and efficacy was reduced when carnosine was administered more than 6 h after ischemia. Our findings suggest that carnosine administered before or after the onset of ischemia exhibits robust efficacy in experimental ischemic stroke. However, the methodological quality of some of the studies was low and testing occurred only in healthy young male animals.     

Individual differences in psychotic effects of ketamine are predicted by brain function measured under placebo

The symptoms of major psychotic illness are diverse and vary widely across individuals. Furthermore, the prepsychotic phase is indistinct, providing little indication of the precise pattern of symptoms that may subsequently emerge. Likewise, although in some individuals who have affected family members the occurrence of disease may be predicted, the specific symptom profile may not. An important question, therefore, is whether predictive physiological markers of symptom expression can be identified. We conducted a placebo-controlled, within-subjects study in healthy individuals to investigate whether individual variability in baseline physiology, as assessed using functional magnetic resonance imaging, predicted psychosis elicited by the psychotomimetic drug ketamine and whether physiological change under drug reproduced those reported in patients. Here we show that brain responses to cognitive task demands under placebo predict the expression of psychotic phenomena after drug administration. Frontothalamic responses to a working memory task were associated with the tendency of subjects to experience negative symptoms under ketamine. Bilateral frontal responses to an attention task were also predictive of negative symptoms. Frontotemporal activations during language processing tasks were predictive of thought disorder and auditory illusory experiences. A subpsychotic dose of ketamine administered during a second scanning session resulted in increased basal ganglia and thalamic activation during the working memory task, paralleling previous reports in patients with schizophrenia. These results demonstrate precise and predictive brain markers for individual profiles of vulnerability to drug-induced psychosis.     

Prospects of micromass culture technology in tissue engineering

The paradigmatic shift to evidence-based dentistry (EBD) that relates to occlusal therapy, selective occlusal adjustment (OA) and stabilization splints therapy (SS) for TMDs has had an unfavourable impact on the teaching of many of the important aspects of occlusion needed in dental practice. The teaching of OA systematically in dental schools has been nearly abandoned because of the belief that OA is an irreversible procedure and gives the impression that it is without merit elsewhere in the management of occlusion. However, a particular dose of knowledge and practice of occlusion that is necessary for all aspects of dental care should be taught systematically in dental schools. The uses and misuses of OA and SS and their limitations should be emphasized because of their importance to bring clinical reality into the dental curriculum. Thus, and irrespective of EBD induced contradictions, OA and SS should still have a significant place in systematically teaching of occlusal therapy. However, there are many more aspects of the management of occlusion that should to be considered. Hopefully, because of their importance, other aspects of the management of occlusion will once again become a significant part of the dental curriculum.     

Coarctation of the aorta: MR imaging

Thirteen patients, aged 3-31 years, with coarctation of the thoracic aorta were examined by magnetic resonance (MR) imaging (total of 14 studies). Eight studies were performed preoperatively and six postoperatively. Catheterization data were available on 12 patients for verification of MR imaging findings. Electrocardiographically gated sagittal and left anterior oblique images best depicted the coarctations; however, involvement of arch vessels was best evaluated on transaxial images. MR imaging readily identified all coarctations but one, their site and extent, and involvement of the arch vessels. In addition, MR images depicted poststenotic dilatation and dilated collateral vessels. In patients studied postoperatively, restenosis could be evaluated, and complications such as postoperative aneurysm and perianastomotic hematoma were identified. MR imaging provides excellent anatomic detail of coarctation of the aorta, potentially obviating the need for angiography.