Coronal biparietal diameter. A reliable alternative to the traditional transverse biparietal diameter

The traditional ultrasonically derived fetal biparietal diameter (BPD) is important in the determination of fetal age, weight, and growth. This measure cannot be obtained, however, with direct occiput anterior or posterior or with a head in the pelvis. This study looked at the BPD utilizing coronal (anatomically at right angles to the traditional BPD through the thalami, third ventricle, and cavum septum pellucidum) rather than transverse section through the fetal head. In 265 patients at 14 to 41 weeks' gestation, simultaneous measurement of the coronal and transverse BPDs revealed that they were interchangeable (r = 0.99). The major drawback of the coronal BPD is the inability to obtain a head circumference because of the absence of the occipitofrontal diameter.     

Intervention studies to reduce the prevalence and incidence of pressure sores: a literature review

Much has been written about the prevention of pressure sores. However, electronic and manual searches located only 10 studies within the literature in the UK that described interventions able to reduce either their incidence or prevalence. All the studies located contained serious methodological flaws. Apparent success in reducing the number or severity of pressure sores could have resulted because staff involved in data collection were aware that the study was being undertaken and thus took more interest in pressure area care. From the review findings it is apparent that there is a dearth of research evidence upon which to base practice in the sphere of pressure sore prevention and further research is urgently required.     

Studies on the coordinate activity and lability of orotidylate phosphoribosyltransferase and decarboxylase in human erythrocytes, and the effects of allopurinol administration

A coordinate relationship between the activities of two sequential enzymes in the de novo pyrimidine biosynthetic pathway has been demonstrated in human red cells. The two enzymes, orotidylate phosphoribosyltransferase and decarboxylase are responsible for the conversion of orotic acid to uridine-5′-monophosphate. Fractionation of red cells, on the basis of increase of specific gravity with cell age, has revealed that these two enzymes have a marked but equal degree of lability in the ageing red cell. It is postulated that orotidylate phosphoribosyltransferase and decarboxylase form an enzyme-enzyme complex, and that the sequential deficiency of these two enzymes in hereditary orotic aciduria may reflect a structural abnormality in this complex.     

Long-term antidepressant administration alters corticotropin-releasing hormone, tyrosine hydroxylase, and mineralocorticoid receptor gene expression in rat brain. Therapeutic implications.

Imipramine is the prototypic tricyclic antidepressant utilized in the treatment of major depression and exerts its therapeutic efficacy only after prolonged administration. We report a study of the effects of short-term (2 wk) and long-term (8 wk) administration of imipramine on the expression of central nervous system genes among those thought to be dysregulated in imipramine-responsive major depression. As assessed by in situ hybridization, 8 wk of daily imipramine treatment (5 mg/kg, i.p.) in rats decreased corticotropin-releasing hormone (CRH) mRNA levels by 37% in the paraventricular nucleus (PVN) of the hypothalamus and decreased tyrosine hydroxylase (TH) mRNA levels by 40% in the locus coeruleus (LC). These changes were associated with a 70% increase in mRNA levels of the hippocampal mineralocorticoid receptor (MR, type I) that is thought to play an important role in mediating the negative feedback effects of low levels of steroids on the hypothalamic-pituitary-adrenal (HPA) axis. Imipramine also decreased proopiomelanocortin (POMC) mRNA levels by 38% and glucocorticoid receptor (GR, type II) mRNA levels by 51% in the anterior pituitary. With the exception of a 20% decrease in TH mRNA in the LC after 2 wk of imipramine administration, none of these changes in gene expression were evident as a consequence of short-term administration of the drug. In the light of data that major depression is associated with an activation of brain CRH and LC-NE systems, the time-dependent effect of long-term imipramine administration on decreasing the gene expression of CRH in the hypothalamus and TH in the LC may be relevant to the therapeutic efficacy of this agent in depression.     

四肢关节专用低场强MRI评估对膝关节损伤的诊断价值

目的：分析四肢关节专用低场强MRI诊断膝关节损伤的临床应用价值。 方法：于2004-12/2005-10解放军总医院全军骨科研究所收治经手术、关节镜检查或临床证实的膝关节损伤患者40例（43个膝关节）。应用Atorscan0.2T永磁型四肢关节专用低场强磁共振机,对膝关节损伤的MRI表现进行分析。 结果：四肢关节专用低场强MRI对半月板、前交叉韧带、骨挫伤等均可作出正确诊断。 结论：四肢关节专用低场强MRI对膝关节损伤的综合诊断具有重要意义,是膝关节损伤较理想的一种非创伤性检查方法。     

The use of the hairless guinea pig in tattoo research.

The study and optimization of tattoo removal continues to be of importance in the dermatology community. Robust animal models whose skin is physiologically similar to humans and who are easily handled are desirable. To this end, we report on our experience with the hairless guinea pig as a model for tattoo research. This research was conducted as part of a larger study toward increased efficacy of laser tattoo removal. Here we report on procedures for both placement and aftercare of tattoos which result in superior tattoo quality and retention.     

Evaluation of the Microstat™ sublingual PCO<Subscript>2</Subscript> monitor in ambulatory patients

Physicians often need to measure arterial PCO₂ in clinical practice. Arterial blood gas sampling is typically available only in hospitals and may be unpleasant for patients. Minimally invasive techniques for measuring PCO₂ offer the potential for overcoming these limitations. The MicroStat monitor non-invasively measures PCO₂ in the sublingual tissues, which should track arterial PCO₂ in hemodynamically stable patients. This was a prospective observational study. Patients undergoing routine cardiac catheterization were recruited. Following arterial cannulation, two sequential sublingual PCO₂ measurements were taken and a contemporaneous arterial sample was sent for blood gas analysis. For each subject we calculated the mean sublingual–arterial CO₂ gradient and the test–retest sublingual PCO₂ difference. Twenty-five patients were studied. Mean sublingual–arterial PCO₂ gradient was +6.8 mmHg (95 % limits of agreement ?3.0 to 16.6 mmHg). Test–retest difference was 3.4 mmHg (95 % limits of agreement ?1.1 to 7.9 mmHg), p = 0.11 (Wilcoxon test), repeatability was 11 mmHg. The MicroStat sublingual PCO₂ monitor over-estimates arterial PCO₂ with wide limits of agreement. Test–retest repeatability was poor. Use of sublingual PCO2 monitoring with the MicroStat monitor cannot currently replace blood gas sampling.     

Inflammation, atrophy, and gastric cancer

The association between chronic inflammation and cancer is now well established. This association has recently received renewed interest with the recognition that microbial pathogens can be responsible for the chronic inflammation observed in many cancers, particularly those originating in the gastrointestinal system. A prime example is Helicobacter pylori, which infects 50% of the world's population and is now known to be responsible for inducing chronic gastric inflammation that progresses to atrophy, metaplasia, dysplasia, and gastric cancer. This Review provides an overview of recent progress in elucidating the bacterial properties responsible for colonization of the stomach, persistence in the stomach, and triggering of inflammation, as well as the host factors that have a role in determining whether gastritis progresses to gastric cancer. We also discuss how the increased understanding of the relationship between inflammation and gastric cancer still leaves many questions unanswered regarding recommendations for prevention and treatment.     

Optimization of opacity function for computed tomography volume rendered images of the prostate using magnetic resonance reference volumes

Objective To enhance the opacity function for computed tomography (CT)-based prostate volume rendered (VR) images using reference magnetic resonance (MR) images. Materials and Methods After simulating on phantoms, ten patients with CT and MR datasets were identified/ registered. Optimal VR images were produced, and intra-modality and cross-modality errors [mean distance in voxel units (VU) from VR partial surface to target] were computed. On the CT VR images, a global transformation was computed to relate the opacity functions obtained using CT reference volumes with those obtained using MR reference volumes. Results The prostate was better visualized on MR than CT, as the intra-modality errors obtained using MR (2.78 ± 1.02 VU) were lower than on CT (3.68 ± 2.15 VU). Despite similar qualitative results as the intra-modality CT images, the cross-modality errors obtained using the individual patient data (2.77 ± 0.99 VU) and using the global transformation (2.89 ± 0.99 VU) were each closer (P = 0.010 and P = 0.011, respectively) to the intra-modality MR errors than were the intra-modality CT errors. Conclusion By optimizing the opacity function using MR reference images, CT VR images of the prostate could closely represent the prostate defined on MR; furthermore, this process can be approximated by a simple transformation. Overall, the errors were reduced to a level (<3 VU) justifying further exploration in CT-based radiotherapy treatment planning. Grant Support: This work was supported by an American Society of Therapeutic Radiology and Oncology (ASTRO) Junior Faculty Research Grant/Award, and was an oral presentation at the annual meeting of ASTRO in Philadelphia, PA in November 2006.