Histamine H1 receptor knockout mice exhibit impaired spatial memory in the eight-arm radial maze

Background and purpose:

In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H₁ and H₂ receptors and the presynaptic H₃ autoreceptor, which also acts as a heteroreceptor. The H₁ receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H₁ receptor in spatial reference and working memory formation, H₁ receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H₁ receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H₁ receptor-KO mice in terms of emotional behaviour in the light–dark box.

Experimental approach:

Mice lacking the H₁ receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.

Key results:

The H₁ receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H₁ receptor-KO and WT mice were observed in the light–dark test.

Conclusions and implications:

The spatial memory deficits of the H₁ receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system.     

Regional radiotherapy versus an axillary lymph node dissection after lumpectomy: a safe alternative for an axillary lymph node dissection in a clinically uninvolved axilla in breast cancer. A case control study with 10 years follow up

Background

To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.

Methods

36 patients were studied pre- and post-radiotherapy with¹⁸FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.

Results

There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)

Conclusion

Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone.     

The Prevalence,Causes, and Consequences of Experiencing a Life Crisis During Medical School

Background: Little is known about the prevalence, causes, and consequences of experiencing a major life crisis during medical school. Purpose: The objective is to describe the prevalence, causes, and consequences through internship of experiencing a major life crisis while enrolled as a medical student at Uniformed Services University (USU). Method: USU graduates from 1980 to 1999 were surveyed regarding their experiences at USU and career milestones. Predictor markers were obtained from the USU Admissions, Promotions, and Registrar's office. Outcome data were derived from a survey of intern program directors from the years 1993 to 1999. Results: There were 1,807 (67%) of USU graduates who responded to our survey. There were 394 (22%) who reported experiencing a major life crisis during medical school. Graduates reporting a major life crisis performed slightly poorer in terms of basic science GPAs (2.95 vs. 2.85, p <.001), USMLE exam scores, and performance ratings by their program directors than did graduates who did not experience a crisis. Conclusions: A large fraction of medical students experience major life crises. The effects of these crises may persist throughout internship.     

Liquidation wahlärztlicher Leistungen

Ohne Zusammenfassung     

Kosten einer Bioresonanztherapie bei Asthma bronchiale und Allergien

Abstrakt 1. Hinsichtlich der Frage der Anerkennung einer Heilmethode kommt es nicht darauf an, ob eine Methode von der überwiegenden Mehrheit der sogenannten Schulmediziner anerkannt wird, aber auch nicht, ob die betreffende Methode „therapieimmanent“, also von denjenigen, die diese Methode entwickelt haben oder sie anwenden, als wirksam eingesch?tzt wird. Entscheidend ist vielmehr auf die Anerkennung derjenigen Personen abzustellen, die sich von dritter Seite als Wissenschaftler in einem wissenschaftlichen Verfahren mit der Frage der Wirksamkeit der betreffenden Methode auseinandergesetzt haben. 2. Der Wirkmechanismus der Bioresonanztherapie ist nach strengen naturwissenschaftlichen Untersuchungen nicht zu erkl?ren. Diese Methode ist jedoch von der Hufelandgesellschaft, die sich aus 25 ?rztegesellschaften zusammensetzt, die allesamt auch Naturheilverfahren betreiben, anerkannt. (Leits?tze des Bearbeiters)     

痢止蒿化学成分的研究

自云南产痢止蒿(Ajuga forrestii Diels)全草的乙醇提取物中分得5个单体,其中化合物Ⅰ和Ⅱ经波谱分析和化学方法鉴定为新的松香烷型二萜类化合物,分别命名为痢止蒿甲素(ajuforrestin A,I)和痢止蒿乙素(ajuforrestin B,II),其余3个是黄酮类化合物:洋芹素(apigenin)、金合欢素(acacetin)和买麻藤乙素(gnetifolin B)。