Citations

ObjectiveTo determine the proportion of patients who would have an unsuccessful lumbar puncture (LP) due to commonly used LP needles being too short.MethodsThree hundred consecutive adults (age 16–99, mean age 56) who underwent abdominal CT over a 6‐month period were identified. The distance from the skin to the midpoint of the spinal canal was measured in the axial plane, at the level of the iliac crest. This was compared to the length of commonly used spinal needles (88 mm) to assess the number of patients who would have an unsuccessful LP due to this distance being greater than 88 mm from the skin.ResultsIn 72/300 (24%) patients, the midpoint of the spinal canal was greater than 88 mm from the skin. A total of 54/72 (75%) of those patients were female. Of the female participants, 54/159 (34%) had the midpoint of their spinal canal at a distance of greater than 88 mm from the skin. In the male patients, only 18/141 (13%) had a similar finding.ConclusionThis is the first high‐quality study to demonstrate that 24% of the population will have an unsuccessful LP procedure if commonly available spinal needles. We demonstrated that 34% of female patients would have an unsuccessful procedure while, in contrast, a successful LP should be possible in 87% of male patients.

ABSTRACTMutations in leucine‐rich repeat kinase 2 (LRRK2) are found in a significant proportion of late‐onset Parkinson's disease (PD) patients. Elucidating the neuroanatomical localization of LRRK2 will further define LRRK2 function and the molecular basis of PD. Here, we utilize recently characterized monoclonal antibodies to evaluate LRRK2 expression in rodent brain regions relevant to PD. In both mice and rats, LRRK2 is highly expressed in the cortex and striatum, particularly in pyramidal neurons of layer V and in medium spiny neurons within striosomes. Overall, rats have a more restricted distribution of LRRK2 compared with mice. Mice, but not rats, show high levels of LRRK2 expression in the substantia nigra pars compacta. Expression of the pathogenic LRRK2‐G2019S protein from mouse bacterial artificial chromosome (BAC) constructs closely mimics endogenous LRRK2 distribution in the mouse brain. However, LRRK2‐G2019S expression derived from human BAC constructs causes LRRK2 to be expressed in additional neuron subtypes in the rat such as striatal cholinergic interneurons and the substantia nigra pars compacta. The distribution of LRRK2 from human BAC constructs more closely resembles descriptions of LRRK2 in humans and nonhuman primates. Computational analyses of DNA regulatory elements in LRRK2 show a primate‐specific promoter sequence that does not exist in lower mammalian species. These noncoding regions may be involved in directing neuronal expression patterns. Together, these studies will aid in understanding the normal function of LRRK2 in the brain and will assist in model selection for future studies. J. Comp. Neurol. 522:2465–2480, 2014. © 2014 Wiley Periodicals, Inc.

Variable survival outcomes are seen following treatment for aggressive non‐Hodgkin lymphoma (NHL). This study examined whether outcomes for aggressive B‐cell NHL are associated with single nucleotide polymorphisms (SNPs) in oxidative stress‐related genes, which can alter drug metabolism and immune responses. Genotypes for 53 SNPs in 29 genes were determined for 337 patients given anthracycline‐based therapies. Their associations with progression‐free survival (PFS) and overall survival (OS) were estimated by Cox proportional hazard regression; associations with hematologic toxicity were estimated by logistic regression. To validate the findings, the top three SNPs were tested in an independent cohort of 572 DLBCL patients. The top SNPs associated with PFS in the discovery cohort were the rare homozygotes for MPO rs2243828 (hazard ratio [HR] = 1.87, 95% confidence interval [CI] = 1.14–3.06, P = 0.013), AKR1C3 rs10508293 (HR = 2.09, 95% CI = 1.28–3.41, P = 0.0032) and NCF4 rs1883112 (HR = 0.66, 95% CI = 0.43–1.02, P = 0.06). The association of the NCF4 SNP with PFS was replicated in the validation dataset (HR = 0.66, 95% CI = 0.44–1.01, P = 0.05) and the meta‐analysis was significant (HR = 0.66, 95% CI = 0.49–0.89, P < 0.01). The association of the MPO SNP was attenuated in the validation dataset, while the meta‐analysis remained significant (HR = 1.64, 95% CI = 1.12–2.41). These two SNPs showed similar trends with OS in the meta‐analysis (for NCF4, HR = 0.72, 95% CI = 0.51–1.02, P = 0.07 and for MPO, HR = 2.06, 95% CI = 1.36–3.12, P < 0.01). In addition, patients with the rare homozygote of the NCF4 SNP had an increased risk of hematologic toxicity. We concluded that genetic variations in NCF4 may contribute to treatment outcomes for patients with aggressive NHL. Am. J. Hematol. 89:639–645, 2014. © 2014 Wiley Periodicals, Inc.

SummaryBackgroundAutoimmune hepatitis can be rendered treatment‐free, but the difficulty, frequency and risks associated with the pursuit of this outcome are unclear.AimTo describe the frequency that autoimmune hepatitis can be rendered treatment‐free, identify the features that characterise these patients, examine the pathogenic pathways that may sustain or terminate the disease and indicate management protocols that can obtain this result.MethodsStudies cited in Pub Med from 1972–2014 for autoimmune hepatitis, treatment, relapse, remission and outcome were selected.ResultsThe frequency of a treatment‐free state varies from 19% to 40% in patients observed for ≥3 years after drug withdrawal. Complete laboratory resolution and reversion to normal liver tissue prior to drug withdrawal favours this response. The development of cirrhosis during therapy may increase treatment‐dependence. Persistent liver damage and the generation of neo‐antigens during the apoptosis of hepatocytes may perpetuate the disease. Genetic and age‐related effects on the vigour of the immune response may also contribute. Reversion to normal liver tissue is achieved in only 22% of patients during conventional corticosteroid therapy, and the emerging pharmacological and biological interventions may improve this frequency. A management strategy designed to achieve a treatment‐free state accommodates all candidates for this outcome, and it can be modified to a long‐term maintenance strategy as warranted by the clinical response.ConclusionsPermanent drug withdrawal is a treatment outcome that is desirable and achievable in patients with autoimmune hepatitis. Normalisation of liver tests and liver tissue during treatment enhances this occurrence.

Objective The objective of this study was to identify brain regions having aberrant pain-induced activation in migraineurs, thereby gaining insight into particular aspects of pain processing that are atypical in migraineurs. Methods Functional magnetic resonance imaging assessed whole brain responses to painful heat in 24 adult episodic migraineurs who were at least 48 hours pain free and 27 healthy controls. Regions differentially activated in migraineurs compared to controls were identified. Activation intensities in these regions were correlated with headache frequency, number of migraine years, and time to next migraine attack. Results Migraineurs had greater pain-induced activation of lentiform nucleus, fusiform gyrus, subthalamic nucleus, hippocampus, middle cingulate cortex, premotor cortex, somatosensory cortex, and dorsolateral prefrontal cortex, and less activation in precentral gyrus and superior temporal gyrus. There were significant correlations between activation strength and headache frequency for middle cingulate ( r = 0.627, p = 0.001), right dorsolateral prefrontal cortex ( r = 0.568, p = 0.004), left fusiform gyrus ( r = 0.487, p = 0.016), left precentral gyrus ( r = 0.415, p = 0.044), and left hippocampus ( r = 0.404, p = 0.050) and with number of migraine years for left fusiform gyrus ( r = 0.425, p = 0.038). There were no significant correlations between activation strength and time to next migraine attack. Conclusions The majority of regions with enhanced pain-induced activation in headache-free migraineurs participate in cognitive aspects of pain perception such as attending to pain and pain memory. Enhanced cognitive pain processing by migraineurs might reflect cerebral hypersensitivity related to high expectations and hypervigilance for pain.

AbstractVitamin D deficiency is common among patients with end‐stage liver disease (ESLD). The primary aim of our study was to assess the prevalence of vitamin D deficiency, secondary hyperparathyroidism, and bone disease in patients with ESLD awaiting LT.MethodsWe retrospectively studied 190 patients at our center. Serum total 25‐hydroxyvitamin D (25‐OH D), parathyroid hormone (PTH), calcium, and bone mineral analysis (BMA) were recorded. Standard World Health Organization (WHO) criteria were used to diagnose osteopenia/osteoporosis. Only patients with normal serum creatinine were analyzed.ResultsThirty‐two of 190 patients were excluded from the final analysis (missing serum total 25‐OH D levels in three patients and elevated serum creatinine, 29 patients). 105 of 158 (66.4%) evaluable patients had 25‐OH D levels <25 ng/mL. Patients included in the analysis (n = 158) were divided according to serum total 25‐OH D levels: 0–10 ng/mL (n = 23), 11–20 ng/mL (n = 64), and >20 ng/mL (n = 71). There were no significant differences in mean serum PTH and corrected calcium levels among the three subgroups. Only three patients had elevated serum PTH. Patients with total 25‐OH D ≤ 10 ng/mL had higher model for end‐stage liver disease (MELD) scores vs. those with 25‐OH D > 20 ng/mL (13.3 ± 3, range 8–21, vs. 11.9 ± 3.4, range 6–29, p = 0.004). Irrespective of vitamin D status, bone disease was present in 64.6% of patients.ConclusionLow vitamin D levels and bone disease are common among patients with ESLD awaiting LT. Despite a high prevalence of low serum total 25‐OH D, our cohort maintained normal corrected calcium levels and did not develop secondary hyperparathyroidism. We propose that free serum 25‐OH D and vitamin D‐binding protein may be necessary to accurately establish the diagnosis of vitamin D deficiency in the setting of ESLD. Additional studies are needed to further define mechanisms of bone disease in patients with ESLD.

Hemodynamic factors are thought to play an important role in the initiation, growth, and rupture of cerebral aneurysms. In-vitro studies have demonstrated a correlation between the magnitude and distribution of wall shear stress (WSS) and biological response of both endothelial cells and smooth muscle cells [1–3]. In elastase induced saccular aneurysms, low WSS (below 0.5 Pa) was found to have a correlation with altered expression of biological markers [4]. Localized regions of rapid aneurysm growth in-vivo have been shown to be associated with regions where WSS is below a critical value of 0.1 Pa [5]. Further, aspect ratio (AR), the ratio of the maximum diameter of the aneurysm to the width of the aneurysm neck, has been correlated with elevated risk of rupture [6]. The purpose of the current study is to explore the possibility of creating elastase induced aneurysms in rabbits with a range of aspect ratios (ratio of aneurysm height/neck) and evaluate the existence of a correlation between aspect ratio and WSS distribution. Aneurysms with ARs from 0.98 to 2.8 were created at the origin of the right common carotid artery (n = 30). Qualitative differences in WSS distribution were found in the high AR aneurysms (HARA) (AR>1.6) and low AR aneurysms (LARA) (AR<1.6) [7].

Since Blix noted that force varies with muscle length [1], many investigators have worked to characterize the passive length-tension properties of skeletal muscle in the tissue’s fiber direction [2]. However, few reports have examined the properties of muscle in either transverse extension or in longitudinal shear [3–4]. Material properties in these three directions are needed to fully characterize computational models, which generally describe muscle as being transversely isotropic, hyperelastic, and isovolumetric [3–6]. Further, previous studies reporting tri-planar material properties indicate that muscle tissue is stiffer in the transverse direction compared to the longitudinal direction [3–4]. This counters conventional notions of transversely isotropic materials, which are generally stiffer in the fiber direction.