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91.

Introduction

The purpose of this study was to investigate the significance of the inflammatory markers on admission in the isolation of a causative pathogen in patients with spinal infection. Spinal infection is treated frequently at spinal units and can encompass a broad range of clinical entities. Its diagnosis is often delayed because of the difficulty of identifying the responsible pathogen.

Methods

Patients with spinal infection treated in our institution over a period of eight years were identified and their notes studied retrospectively. Admission C-reactive protein (CRP), white cell count (WCC) as well as co-morbidities and mode of pathogen identification were recorded. Overall, 96 patients were included in the study.

Results

The CRP levels on admission were correlated significantly with the overall potential for isolation of a pathogen (p<0.0001) and positive biopsy cultures (p=0.0016). Admission WCC levels were associated significantly with the overall potential for isolation of a pathogen (p=0.0003) and positive biopsy cultures (p=0.0023). Both CRP and WCC levels were significantly negatively correlated with the duration of the preceding symptoms (p=0.0003 and p<0.0001 respectively). Delay in presentation was significantly negatively correlated with organism isolation (p=0.0001). Multivariate analyses identified the delay in presentation as the strongest independent variable for organism isolation (p=0.014) in cases of spontaneous spinal infection when compared with the admission CRP level (p=0.031) and WCC (p=0.056).

Conclusions

In spontaneous spinal infection, delay in presentation is the strongest independent variable for organism isolation. High inflammatory marker levels on admission are a useful prognostic marker for the overall potential of isolating a causative organism either by blood cultures or by biopsy in patients with negative blood cultures. Furthermore, the admission inflammatory marker levels allow for treating surgeons to counsel their patients of the likelihood of achieving a positive microbiological yield from biopsy.  相似文献   
92.
It is becoming increasingly clear that our residential microbes, the key constituents in the human microbiome, are centrally involved in many aspects of our physiology. In particular, the ancient and dominant gastric bacteria Helicobacter pylori are highly interactive with human physiology. In modern times, H. pylori has been disappearing, which consequently affects the interactions between luminal bacteria and epithelial, lymphoid, and neuroendocrine cells. A growing body of evidence indicates that H. pylori protects against childhood-onset asthma, probably through the gastric recruitment of regulatory T cells. The phenomenon of disappearing ancient microbiota may be a general paradigm driving the diseases of modernity.  相似文献   
93.
Recent studies suggest that computerized cognitive training leads to improved performance in related but untrained tasks (i.e. transfer effects). However, most study designs prevent disentangling which of the task components are necessary for transfer. In the current study, we examined whether training on two variants of the adaptive dual n-back task would affect untrained task performance and the corresponding electrophysiological event-related potentials (ERPs). Forty three healthy young adults were trained for three weeks with a high or low interference training variant of the dual n-back task, or they were assigned to a passive control group. While n-back training with high interference led to partial improvements in the Attention Network Test (ANT), we did not find transfer to measures of working memory and fluid intelligence. ERP analysis in the n-back task and the ANT indicated overlapping processes in the P3 time range. Moreover, in the ANT, we detected increased parietal activity for the interference training group alone. In contrast, we did not find electrophysiological differences between the low interference training and the control group. These findings suggest that training on an interference control task leads to higher electrophysiological activity in the parietal cortex, which may be related to improvements in processing speed, attentional control, or both.  相似文献   
94.

Introduction

This study aimed to determine whether ethnic differences show different patterns of arterial disease in the lower limb.

Methods

A prospective analysis of 100 consecutive patients with 160 lower limb arteriograms was performed looking at the pattern of disease with relation to ethnicity in Trinidad and Tobago.

Results

There were 53 male and 47 female patients with an age range of 43–90 years (mean: 66 years). Of the 100 patients, 45 were of East Indian descent, 36 of Afro-Caribbean descent, 14 of mixed descent and 5 had other backgrounds. There were 32 smokers and 69 diabetics.The most commonly affected artery in East Indians was the anterior tibial artery (ATA, 70%) followed by the peroneal artery (60%), superficial femoral artery (SFA, 60%), posterior tibial artery (PTA, 57%) and tibioperoneal trunk (TPT, 39%). In Afro-Caribbeans, the most commonly affected artery was the ATA (79%) followed by the PTA (74%), peroneal artery (66%) and TPT (55%). The mixed group showed the PTA (85%) to be most diseased followed by the peroneal artery (75%), ATA (70%), SFA (70%), dorsalis pedis artery (DPA, 60%) and TPT (50%). Overall, the most diseased vessel in all groups was the ATA (73%) followed by the PTA (66%), peroneal artery (64%), SFA (59%), TPT (46%), DPA (38%), popliteal artery (31%) and medial plantar artery (MPA, 29%), with the proximal vessels not being affected severely.

Conclusions

Ethnic divisions were only statistically significant (p<0.05) with East Indians showing worse disease in the profunda femoris artery and Afro-Caribbeans showing worse disease in the PTA, DPA and MPA. This suggests that environmental factors may play a significant role in the disease process including smoking and dietary factors rather than purely genetics.  相似文献   
95.

Introduction

In 2009 the Department of Health instructed McKinsey & Company to provide advice on how commissioners might achieve world class National Health Service productivity. Asymptomatic inguinal hernia repair was identified as a potentially cosmetic procedure, with limited clinical benefit. The Birmingham and Solihull primary care trust cluster introduced a policy of watchful waiting for asymptomatic inguinal hernia, which was implemented across the health economy in December 2010. This retrospective cohort study aimed to examine the effect of a change in clinical commissioning policy concerning elective surgical repair of asymptomatic inguinal hernias.

Methods

A total of 1,032 patients undergoing inguinal hernia repair in the 16 months after the policy change were compared with 978 patients in the 16 months before. The main outcome measure was relative proportion of emergency repair in groups before and after the policy change. Multivariate binary logistic regression was used to adjust the main outcome for age, sex and hernia type.

Results

The period after the policy change was associated with 59% higher odds of emergency repair (3.6% vs 5.5%, adjusted odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.03–2.47). In turn, emergency repair was associated with higher odds of adverse events (4.7% vs 18.5%, adjusted OR: 3.68, 95% CI: 2.04–6.63) and mortality (0.1% vs 5.4%, p<0.001, Fisher’s exact test).

Conclusions

Introduction of a watchful waiting policy for asymptomatic inguinal hernias was associated with a significant increase in need for emergency repair, which was in turn associated with an increased risk of adverse events. Current policies may be placing patients at risk.  相似文献   
96.

Introduction

An individual’s genetic background plays a significant role in his or her chances of developing an abdominal aortic aneurysm (AAA). This risk is likely to be due to a combination of multiple small effect genetic factors acting together, resulting in considerable difficulty in the identification of these factors.

Methods

Methods for the identification of genetic factors associated with disease are usually based on the analysis of genetic variants in case-control studies. Over the last decade, owing to advances in bioinformatics and laboratory technology, these studies have progressed from focusing on the examination of a single genetic variant in each study to the examination of many millions of variants in a single experiment. We have conducted a series of such experiments using these methods.

Results

Our original methods using candidate gene approaches led to the initial identification of a genetic variant in the interleukin-10 gene associated with AAA. However, further studies failed to confirm this association and highlighted the necessity for adequately powered studies to be conducted, as well as the need for confirmatory studies to be performed, prior to the acceptance of a variant as a risk for disease. The subsequent application of genomic techniques to our sample set, in a global collaboration, has led to the identification of three robustly verified risk loci for AAA in the LRP1, LDLR and SORT1 genes.

Conclusions

Genomic studies of AAA have led to the identification of new pathways involved in the pathogenesis of AAA. The exploration of these pathways has the potential to unlock new avenues for therapeutic intervention to prevent the development and progression of AAA.  相似文献   
97.
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research.  相似文献   
98.
Infection with SARS-CoV-2 leading to COVID-19 induces hyperinflammatory and hypercoagulable states, resulting in arterial and venous thromboembolic events. Deep vein thrombosis (DVT) has been well reported in COVID-19 patients. While most DVTs occur in a lower extremity, involvement of the upper extremity is uncommon. In this report, we describe the first reported patient with an upper extremity DVT recurrence secondary to COVID-19 infection.  相似文献   
99.
Fifty-one patients with previously untreated or minimally treated chronic myelogenous leukemia in chronic phase received human alpha interferon 3 to 9 X 10(6) units intramuscularly (IM) daily until complete hematologic remission, then at doses ranging from 3 X 10(6) units every other day to 9 X 10(6) units daily. Forty-one (80%) patients achieved a hematologic response, 36 (71%) of them attaining a complete hematologic remission with normal peripheral WBC and differential counts. Responding patients showed continuous but slow normalization of several other blood and marrow parameters including platelet counts, serum lactic dehydrogenase and B12 levels, and marrow cellularity and maturation index. Suppression of the Philadelphia chromosome on serial cytogenetic studies of marrow metaphases was documented in 20 of the 36 patients who achieved complete hematologic remission (56%; 39% of total group), eight of whom (22%) had a decrease of the Philadelphia chromosome-positive metaphases to less than 35%. These changes were persistent for 6 months or longer in 18 patients, seven of whom had continuous suppression of the Philadelphia chromosome to less than 90% for a median of 30+ months (range 21+ to 39+ months). After a median follow-up period of 37 months, 25 patients remain in continued disease control with interferon therapy. The projected 3-year survival rate is 76%, with a yearly death rate of 6%, 9%, and 9% in the first 3 years. Response, Philadelphia chromosome suppression, and survival were significantly better among patients in the low-risk category compared to intermediate- and high-risk categories, as defined by a multivariate analysis-derived prognostic model. The projected 3- year survival rate was 94% for patients who achieved a complete hematologic remission on interferon therapy and 45% for those who did not. Thirteen patients have developed blastic crisis, six with lymphoid and three with undifferentiated morphology. We conclude that human leukocyte alpha interferon effectively controls chronic myeloid leukemia and allows reappearance of diploid hemopoietic cells in some patients.  相似文献   
100.
The precise mechanisms regulating T-helper function have been intensively investigated. We and others have recently identified a new T-cell-B-cell-activating molecule called T-BAM that directs B-cell differentiation by interacting with the CD40 molecule on B cells. Using a specific monoclonal antibody against T-BAM (5C8), we have previously shown that T-BAM expressing T cells are predominantly CD4+CD8- and in normal lymphoid tissue have a unique distribution. However, no information has been obtained regarding the phenotype and functional properties of human neoplastic T cells. Therefore, we investigated T- BAM expression immunohistochemically in 87 well-characterized T-cell non-Hodgkin's lymphomas and lymphoid leukemias (LL). We found that 21/81 neoplasms expressed detectable T-BAM and these positive tumors belong almost exclusively to the CD4+CD8- subtype. In addition, to determine whether T-BAM expression could be induced on T-BAM-LL cells, we activated T-BAM-LLs in vitro and showed that T-BAM could be upregulated only in CD4+CD8- tumors. Our studies clearly show that T- BAM is constitutively expressed in a large number of T-cell neoplasms with a relative mature phenotype (CD4+CD8-) and that only CD4+ neoplastic T cells can be induced in vitro to express this molecule. Additional studies are necessary to identify the biologic significance of T-BAM expression and its potential and clinical implications.  相似文献   
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