Caffeine restores regional brain activation in acute hypoglycaemia in healthy volunteers.

AIMS: Caffeine enhances counterregulatory responses to acute hypoglycaemia. Our aim was to explore its effects on cortical function, which are not known at present. METHODS: Regional brain activation during performance of the four-choice reaction time (4CRT) at different levels of complexity was measured using functional magnetic resonance imaging (fMRI) at euglycaemia (5 mmol/l) and hypoglycaemia (2.6 mmol/l) in the presence and absence of caffeine in six healthy right-handed men. RESULTS: During hypoglycaemia, caffeine enhanced adrenaline responses to hypoglycaemia (2.5 +/- 0.7 nmol/l to 4.0 +/- 1.0 nmol/l, P = 0.01) and restored the brain activation response to the non-cued 4CRT, the linear increases in regional brain activation associated with increased task complexity and the ability to respond to a cue that were lost in hypoglycaemia alone. CONCLUSIONS: Caffeine can sustain regional brain activation patterns lost in acute hypoglycaemia, with some restoration of cortical function and enhanced adrenaline responsiveness. A methodology has been established that may help in the development of therapies to protect against severe hypoglycaemia in insulin therapy for patients with diabetes and problematic hypoglycaemia.     

The Relationship Between Psychogenic Cough and the Diagnosis and Misdiagnosis of Asthma: A Review

The differential diagnoses of persistent nonproductive cough include numerous pulmonary and nonpulmonary organic disorders as well as functional illnesses. Many diseases can cause cough, and several studies have shown asthma among the most common etiologies associated with chronic cough in adult nonsmokers, as well as children. Psychogenic cough and its relationship to asthma and other asthma-like illnesses is complex since distinct maladies with similar features may coexist individually or in combination in any given patient. While chronic cough may occur as a sole presenting manifestation of bronchial asthma in all age groups, recent findings suggest that most children with persistent cough without other respiratory symptoms do not have asthma. Since several organic, as well as functional diseases, may present with persistent cough as their sole manifestation in either adults or children, cough should not be used as a single or major determinant to diagnose and treat asthma, especially when empirically focused therapy trials fail. Given the range of illnesses causing cough, no single management guideline can be expected to be universally effective.     

Functional Results Following Elective Laparoscopic Sigmoidectomy After CT-Proven Diagnosis of Acute Diverticulitis Evaluation of 43 Patients and Review of the Literature

We performed a prospective study to analyze the functional results following elective laparoscopic sigmoidectomy for computed tomography (CT)-proven diagnosis of acute diverticulitis and review the literature. Forty-three of 45 available patients (96%) who had laparoscopic sigmoidectomy for CT-proven acute diverticulitis answered, after a mean time of 40 months, a questionnaire exploring new abdominal symptoms, bowel function, and the patient’s own judgement of the surgical outcome. Surgical technique aimed at removing all the sigmoid by taking down the splenic flexure and do a colorectal anastomosis. Four patients (9%) complained of new abdominal pain. Bowel function was reported as better for 24 patients (56%), unchanged for 16 patients (37%), and worse for 3 (7%). Twenty patients (47%) considered their final result as excellent to good, 17 patients (40%) as satisfying, and 6 patients (13%) as mediocre. Male gender, absence of preoperative history compatible with an irritable bowel syndrome, length of resected sigmoid and residual acute inflammation on histology are statistically predictive of a better postoperative degree of satisfaction. After elective laparoscopic sigmoidectomy for CT-proven diverticulitis, a great majority of patients are very satisfied with their postoperative general comfort.     

Parallel imaging reconstruction for arbitrary trajectories using k-space sparse matrices (kSPA).

Although the concept of receiving MR signal using multiple coils simultaneously has been known for over two decades, the technique has only recently become clinically available as a result of the development of several effective parallel imaging reconstruction algorithms. Despite the success of these algorithms, it remains a challenge in many applications to rapidly and reliably reconstruct an image from partially-acquired general non-Cartesian k-space data. Such applications include, for example, three-dimensional (3D) imaging, functional MRI (fMRI), perfusion-weighted imaging, and diffusion tensor imaging (DTI), in which a large number of images have to be reconstructed. In this work, a systematic k-space-based reconstruction algorithm based on k-space sparse matrices (kSPA) is introduced. This algorithm formulates the image reconstruction problem as a system of sparse linear equations in k-space. The inversion of this system of equations is achieved by computing a sparse approximate inverse matrix. The algorithm is demonstrated using both simulated and in vivo data, and the resulting image quality is comparable to that of the iterative sensitivity encoding (SENSE) algorithm. The kSPA algorithm is noniterative and the computed sparse approximate inverse can be applied repetitively to reconstruct all subsequent images. This algorithm, therefore, is particularly suitable for the aforementioned applications.     

图片学习测验在识别老年人轻微认知功能损害中的作用

目的　分析图片学习测验在识别老年人轻微认知功能损害 (MCI)中的作用。方法　选择符合MCI诊断标准的老年人 4 8例与正常对照组 5 6名完成图片学习测验、简易智能状态检查、听觉词语学习测验及多种非记忆测验。结果　图片学习测验的 3个记忆指标 (图片短时记忆、延迟记忆和学习记忆 )在MCI与正常对照组之间有非常显著的差异。已经给出这三个图片记忆指标区分MCI与正常老年人的划界分、敏感性和特异性。结论　图片记忆操作简便、信度和效度好 ,可以作为临床医师筛选MCI的有效工具     

Neuropsychological changes during steady-state drug use,withdrawal and abstinence in primary benzodiazepine-dependent patients

Impairment on neuropsychological tests during steady-state drug use and withdrawal, and after discontinuation of benzodiazepines, was studied in primary benzodiazepine-dependent patients. One group of patients was tested before and the other group after the initiation of a gradual tapering-off of the drug, and both groups were tested approximately 1 year later. At the initial assessment, both groups of patients showed impairment on most of the tests of general intelligence and on several of the tests in the Halstead-Reitan battery, as well as on a test of nonverbal memory, in comparison with healthy controls. At follow-up the patient groups had reached the level of the control group. This study confirmed earlier observations of neuropsychological deficits in long-term benzodiazepine-using patients and demonstrated that these changes are at least partly reversible by discontinuing drug intake.     

Malignant chiasmal glioma: a rare cause of rapid visual loss

The clinical, neuroradiological, and histological findings of an adult patient suffering from malignant optic glioma is reported. Rapid visual deterioration was misdiagnosed for several months until biopsy confirmed the tumor. The patient died despite radiation therapy nine months after first symptoms. Our presentation will focus on the problems of diagnosing and establishing therapeutic procedures in this rare malignant neoplasm.     

时滞系统鲁棒稳定性的新判据

基于Ｌｙａｐｎｕｏｖ泛函方法，研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉０鲁棒稳定性，给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的，或有时减少了已有结果的保守性。