Demographic History of Indigenous Populations in Mesoamerica Based on mtDNA Sequence Data

The genetic characterization of Native American groups provides insights into their history and demographic events. We sequenced the mitochondrial D-loop region (control region) of 520 samples from eight Mexican indigenous groups. In addition to an analysis of the genetic diversity, structure and genetic relationship between 28 Native American populations, we applied Bayesian skyline methodology for a deeper insight into the history of Mesoamerica. AMOVA tests applying cultural, linguistic and geographic criteria were performed. MDS plots showed a central cluster of Oaxaca and Maya populations, whereas those from the North and West were located on the periphery. Demographic reconstruction indicates higher values of the effective number of breeding females (Nef) in Central Mesoamerica during the Preclassic period, whereas this pattern moves toward the Classic period for groups in the North and West. Conversely, Nef minimum values are distributed either in the Lithic period (i.e. founder effects) or in recent periods (i.e. population declines). The Mesomerican regions showed differences in population fluctuation as indicated by the maximum Inter-Generational Rate (IGRmax): i) Center-South from the lithic period until the Preclassic; ii) West from the beginning of the Preclassic period until early Classic; iii) North characterized by a wide range of temporal variation from the Lithic to the Preclassic. Our findings are consistent with the genetic variations observed between central, South and Southeast Mesoamerica and the North-West region that are related to differences in genetic drift, structure, and temporal survival strategies (agriculture versus hunter-gathering, respectively). Interestingly, although the European contact had a major negative demographic impact, we detect a previous decline in Mesoamerica that had begun a few hundred years before

Mechanisms of T cell organotropism

F.M.M.-B. is supported by the British Heart Foundation, the Medical Research Council of the UK and the Gates Foundation

Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics

Temporomandibular joint dysfunction and orthognathic surgery: a retrospective study

<p>Abstract</p> <p>Background</p> <p>Relations between maxillo-mandibular deformities and TMJ disorders have been the object of different studies in medical literature and there are various opinions concerning the alteration of TMJ dysfunction after orthognathic surgery. The purpose of the present study was to evaluate TMJ disorders changes before and after orthognathic surgery, and to assess the risk of creating new TMJ symptoms on asymptomatic patients.</p> <p>Methods</p> <p>A questionnaire was sent to 176 patients operated at the Maxillo-Facial Service of the Lille's 2 Universitary Hospital Center (Chairman Pr Joël Ferri) from 01.01.2006 to 01.01.2008. 57 patients (35 females and 22 males), age range from 16 to 65 years old, filled the questionnaire. The prevalence and the results on pain, sounds, clicking, joint locking, limited mouth opening, and tenseness were evaluated comparing different subgroups of patients.</p> <p>Results</p> <p>TMJ symptoms were significantly reduced after treatment for patients with pre-operative symptoms. The overall subjective treatment outcome was: improvement for 80.0% of patients, no change for 16.4% of patients, and an increase of symptoms for 3.6% of them. Thus, most patients were very satisfied with the results. However the appearance of new onset of TMJ symptoms is common. There was no statistical difference in the prevalence of preoperative TMJ symptoms and on postoperative results in class II compared to class III patients.</p> <p>Conclusions</p> <p>These observations demonstrate that: there is a high prevalence of TMJ disorders in dysgnathic patients; most of patients with preoperative TMJ signs and symptoms can improve TMJ dysfunction and pain levels can be reduced by orthognathic treatment; a percentage of dysgnathic patients who were preoperatively asymptomatic can develop TMJ disorders after surgery but this risk is low.</p

Treatment of atypical central neurocytoma in a child with high dose chemotherapy and autologous stem cell rescue

The authors describe a 9 month old female with recurrent atypical central neurocytoma and leptomeningeal spread treated with high dose chemotherapy, autologous stem cell rescue, and adjuvant therapy. She had a complete response to therapy and was disease free at 4 years of age until a recurrence 6 months later. The use of intensive chemotherapy followed by autologous stem cell rescue for atypical neurocytoma may be considered as an adjunct to surgical therapy in young patients with atypical neurocytoma not amenable to radiation therapy

Ultrasound assessment of the lateral collateral ligamentous complex of the elbow: imaging aspects in cadavers and normal volunteers

OBJECTIVE: The Lateral Collateral Ligamentous complex (LCL) is an important stabiliser of the elbow. It has a Y-shaped structure with three components. In this study, we sought to describe the ultrasound aspect of the individual components of this ligamentous complex and to evaluate the performance of ultrasound in both cadavers and in normal subjects. METHODS: Ten cadaveric elbow specimens underwent high-frequency ultrasound. Two specimens were sliced and two were dissected for anatomical correlation. Ten elbows of normal subjects were also evaluated by ultrasound. The findings were compared. RESULTS: The three components of the LCL could be visualised in all specimens and normal subjects with the exception of the proximal portion of one specimen. In 80% of the specimens and 100% of the healthy volunteers the proximal portion of the LCL could be separated from the extensor tendons. CONCLUSION: High-resolution ultrasound can assess all components of the LCL of the elbow and can distinguish them from surrounding structures

Induction of the interleukin 6/ signal transducer and activator of transcription pathway in the lungs of mice sub-chronically exposed to mainstream tobacco smoke

<p>Abstract</p> <p>Background</p> <p>Tobacco smoking is associated with lung cancer and other respiratory diseases. However, little is known about the global molecular changes that precede the appearance of clinically detectable symptoms. In this study, the effects of mainstream tobacco smoke (MTS) on global transcription in the mouse lung were investigated.</p> <p>Methods</p> <p>Male C57B1/CBA mice were exposed to MTS from two cigarettes daily, 5 days/week for 6 or 12 weeks. Mice were sacrificed immediately, or 6 weeks following the last cigarette. High density DNA microarrays were used to characterize global gene expression changes in whole lung. Microarray results were validated by Quantitative real-time RT-PCR. Further analysis of protein synthesis and function was carried out for a select set of genes by ELISA and Western blotting.</p> <p>Results</p> <p>Globally, seventy nine genes were significantly differentially expressed following the exposure to MTS. These genes were associated with a number of biological processes including xenobiotic metabolism, redox balance, oxidative stress and inflammation. There was no differential gene expression in mice exposed to smoke and sampled 6 weeks following the last cigarette. Moreover, cluster analysis demonstrated that these samples clustered alongside their respective controls. We observed simultaneous up-regulation of <it>interleukin 6 </it>(<it>IL-6</it>) and its antagonist, <it>suppressor of cytokine signalling </it>(<it>SOCS3</it>) mRNA following 12 weeks of MTS exposure. Analysis by ELISA and Western blotting revealed a concomitant increase in total IL-6 antigen levels and its downstream targets, including phosphorylated signal transducer and activator of transcription 3 (Stat3), basal cell-lymphoma extra large (BCL-XL) and myeloid cell leukemia 1 (MCL-1) protein, in total lung tissue extracts. However, in contrast to gene expression, a subtle decrease in total SOCS3 protein was observed after 12 weeks of MTS exposure.</p> <p>Conclusion</p> <p>Global transcriptional analysis identified a set of genes responding to MTS exposure in mouse lung. These genes returned to basal levels following smoking cessation, providing evidence to support the benefits of smoking cessation. Detailed analyses were undertaken for IL-6 and its associated pathways. Our results provide further insight into the role of these pathways in lung injury and inflammation induced by MTS.</p

Interfering RNA and HIV: Reciprocal Interferences

In this review, a quick presentation of what interfering RNA (iRNA) are—small RNA able to exert an inhibition on gene expression at a posttranscriptional level, based on sequence homology between the iRNA and the mRNA—will be given. The many faces of the interrelations between iRNA and viruses, particularly HIV, will be reviewed. Four kinds of interactions have been described: i) iRNA of viral origin blocking viral RNA, ii) iRNA of viral origin downregulating cellular mRNA, iii) iRNA of cellular origin (microRNA) targeting viral RNA, and iv) microRNA downregulating cellular mRNA encoding cell proteins used by the virus for its replication. Next, HIV strategies to manipulate these interrelations will be considered: suppression of iRNA biosynthesis by Tat, trapping by the HIV TAR sequence of a cell component, TRBP, necessary for iRNA production and action, and induction by the virus of some microRNA together with suppression of others. Then, we will discuss the putative effects of these mutual influences on viral replication as well as on viral latency, immune response, and viral cytopathogenicity. Finally, the potential consequences on the human infection of genetic polymorphisms in microRNA genes and the therapeutic potential of iRNA will be presented