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1.
Currently, there are 18 different religious communities living in Lebanon. While evolving primarily within Lebanon, these communities show a level of local isolation as demonstrated previously from their Y-haplogroup distributions. In order to trace the origins and migratory patterns that may have led to the genetic isolation and autosomal clustering in some of these communities we analyzed Y-chromosome STR and SNP sample data from 6327 individuals, in addition to whole genome autosomal sample data from 609 individuals, from Mount Lebanon and other surrounding communities. We observed Y chromosome L1b Levantine STR branching that occurred around 5000 years ago. Autosomal DNA analyses suggest that the North Lebanese Mountain Maronite community possesses an ancestral Fertile Crescent genetic component distinct from other populations in the region. We suggest that the Levantine L1b group split from the Caucasus ancestral group around 7300 years ago and migrated to the Levant. This event was distinct from the earlier expansions from the Caucasus region that contributed to the wider Levantine populations. Differential cultural adaption by populations from the North Lebanese Mountains are clearly aligned with the L1b haplotype STR haplogroup clusters, indicating pre-existing and persistent cultural barriers marked by the transmission of L1b lineages. Our findings highlight the value of uniparental haplogroups and STR haplotype data for elucidating biosocial events among these populations.Subject terms: Population genetics, Computational biology and bioinformatics  相似文献   
2.
Increasing evidence suggests that brain pulsatility is involved in the pathophysiology of various neurological and psychiatric disorders. However, it remains unclear whether high brain pulsatility is damaging to or protective of the brain in normal conditions, and this could depend on the age of the individual and the methods used to measure brain pulsatility. The goal of our study was to investigate associations between subcortical volumes and brain pulsatility as assessed with ultrasound in healthy young adults using both a conventional method (transcranial Doppler pulsatility index [TCD-PI]) and the innovative method of tissue pulsatility imaging (TPI), which allows a high level of detection of small brain movements (micrometers). Twenty-five females aged 18–55 with no history of significant medical disorder underwent magnetic resonance imaging and ultrasound assessment. The volumes of six subcortical regions known to be particularly sensitive to change in cerebral blood flow were measured and compared with brain pulsatility as assessed with TCD-PI and TPI. TCD-PI and TPI measures positively correlated with all subcortical regions, with the caudate nucleus having the strongest association. Linear regressions found that TCD-PI and TPI measures of brain pulsatility explained 16% to 67% of the variance of the subcortical volumes. Our results suggest that a greater pulsatility as assessed with ultrasound in healthy young adults may constitute a protective factor for brain structure. Ultrasound measures of brain pulsatility may be appropriate to provide costless, non-invasive, portable and highly sensitive markers of cerebral blood flow pulsatility related to brain structure.  相似文献   
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STUDY OBJECTIVES: The mechanism(s) by which nasal continuous positive airway pressure (CPAP) is effective in the treatment of Cheyne-Stokes respiration (CSR) in patients with congestive heart failure (CHF) remains uncertain, and may involve an increase in total oxygen body stores (dampening), changes in central and peripheral controller gain, and/or improvement in cardiac function. The purpose of this study was to evaluate the effects of nasal CPAP on total oxygen stores, as measured by the rate of fall of arterial oxyhemoglobin saturation (dSaO(2)/dt), to determine if dampening may play a role in the attenuation of CSR in patients with CHF. DESIGN: Prospective controlled trial. SETTING: University hospital. PATIENTS: Nine male patients (mean +/- SD age, 59 +/- 8 years) with CHF and a mean left ventricular ejection fraction (LVEF) of 16 +/- 4%. Interventions and measurements: All patients had known CSR, as identified on a baseline polysomnographic study. Patients then underwent repeat polysomnography while receiving nasal CPAP (9 +/- 0.3 cm H(2)O). The polysomnography consisted of recording of breathing pattern, pulse oximetry, and EEG. dSaO(2)/dt was measured as the slope of a line drawn adjacent to the falling linear portion of the arterial oxygen saturation (SaO(2)) curve associated with a central apnea. All patients underwent echocardiography and right-heart catheterization within 1 month of the study to measure LVEF and cardiac hemodynamics, respectively. RESULTS: There was a significant decrease in the apnea-hypopnea index (AHI) with nasal CPAP, from 44 +/- 27 events per hour at baseline to 15 +/- 24 events per hour with nasal CPAP (p = 0.004). When compared to baseline, dSaO(2)/dt significantly decreased with nasal CPAP from 0.42 +/- 0.15% to 0.20 +/- 0.07%/s (p < 0.001). The postapneic SaO(2), when compared to baseline, significantly increased with nasal CPAP, from 87 +/- 5% to 91 +/- 4% (p < 0.05). The preapneic SaO(2) did not significantly change, from a baseline of 96 +/- 2% to 96 +/- 3% with nasal CPAP (p = 0.8). When compared to baseline, the apnea duration and heart rate did not change with nasal CPAP. While there was a significant correlation noted between baseline postapneic SaO(2) and dSaO(2)/dt (r = 0.8, p = 0.02), no correlation was seen between baseline preapneic SaO(2) and dSaO(2)/dt (r = 0.1, p = 0.7). A significant correlation was noted between baseline dSaO(2)/dt and the AHI (r = 0.7, p = 0.02). With CPAP, there was a significant correlation noted between dSaO(2)/dt and the AHI (R = 0.7, p = 0.04), but no correlation was noted between dSaO(2)/dt and postapneic SaO(2) (R = 0.1, p = 0.8). CONCLUSION: Nasal CPAP significantly decreases dSaO(2)/dt and thus increases total body oxygen stores in patients with CSR and CHF. By increasing oxygen body stores, dampening may be one of the mechanisms responsible for the attenuation of CSR seen with nasal CPAP.  相似文献   
5.
Emotions play a key role in our daily life through their control over our thoughts and behaviors. While it is commonly accepted that depressive patients have emotional perception disorders, it is important to know how these disorders affect patients’ sensory perception to develop products to provide them with better support. In this study, we first examined the existence of modifications in the emotional perception of subjects with minor depressive symptoms (MDS, n = 80) compared with healthy controls (HC, n = 80) using a nonverbal method based on pictures to measure projected emotions and personality traits: the Sense'n Feel? method. The investigated stimuli were two unpleasant and two pleasant odors and one pleasant food product: a madeleine. Second, we investigated the hedonic, familiarity and intensity olfactory perceptions of the subjects using the same stimuli. No significant difference was found in any olfactory qualities between the two groups. Concerning the pleasant olfactory stimuli, however, we did note that the MDS subjects had a significantly lower score for the positive emotion of joy/happiness than the controls. Additionally, the MDS group's attribution of some positive personality traits for the three pleasant stimuli was significantly weaker than that in the HC group. These results could be explained by the affective state of the MDS subjects; they were more anxious and more alexithymic compared with the controls. Further research is needed to validate our study in clinically depressed individuals and to determine whether the modifications of the emotional olfactory perception are due to the disease and/or to neuropsychological alterations.  相似文献   
6.
The hydatid disease is a zoonosis endemic to rural countries, such as those in the Mediterranean region, South America, North Africa, Central Asia and China. Hydatid cysts commonly affect liver and lungs, but less than 100 cases of costal hydatidosis have been reported in the literature. While diagnosis of the disease in commonly affected organs is relatively easy, uncommon locations can prove to be challenging as is the case with costal hydatidosis. Imaging techniques can suggest the diagnosis, but sometimes it remains uncertain until surgery. The treatment is surgical, assisted by long-time Albendazole chemotherapy. We present a rare case of costal hydatidosis, the first one to be reported in Romania according to our review of the literature.  相似文献   
7.
Chronic liver disease and cirrhosis affect hundreds of millions of patients all over the world. The majority of patients with cirrhosis will eventually develop complications related to portal hypertension. One of these recurrent and difficult to treat complications is hepatic encephalopathy. Studies have indicated that overt hepatic encephalopathy affects 30 to 45% of patients with cirrhosis and a higher percentage may be affected by minimal degree of encephalopathy. All of these factors add to the impact of hepatic encephalopathy on the healthcare system and presents a major challenge to the gastroenterologist, hospitalist and primary care physician.  相似文献   
8.
Several studies have shown a direct role of liver atrophy in the pathogenesis of thrombocytopenia of cirrhosis via reduced production of thrombopoeitin. About 181 patients listed for liver transplantation at a single transplant center were evaluated at the time of listing with laboratory tests and volumetric liver measurements using computed tomography. Expected normal liver volume was calculated using the Heinemann formula. Liver volume ratio (LVR) was calculated as actual liver volume over expected liver volume. Patients were predominantly male (70.7%), with viral hepatitis (60.2%), had a mean age of 51.8 years (SD 8.7), model for end stage liver disease (MELD) of 14 (SD 6.4), LVR of 0.95 (SD 0.3), and platelet count of 105 000/mcL (SD 66 000). Platelet count (P < 0.0001) correlated more strongly with LVR than MELD, MELD components (P = 0.27) or serum albumin (P = 0.003). Platelet count (HR 0.987, 95% CI 0.979–0.994, P = 0.001) was a strong independent predictor of mortality. Patients with platelet count < 100 000/mcL had a shorter survival (935 vs. 1396 days, P = 0.002) and higher death rate (42.2% vs. 23.6%, P = 0.01), but no different transplantation rate (36.7% vs. 33.3%, P = 0.64) compared to those with platelet count ≥ 100 000/mcL. Low platelet count corresponds to higher waiting list mortality and is a sign of advanced liver atrophy.  相似文献   
9.
α-Synucleinopathies including idiopathic Parkinson's disease, dementia with Lewy bodies and multiple systems atrophy share overlapping symptoms and pathological hallmarks. Selective neurodegeneration and Lewy pathology are the main hallmarks of α-synucleinopathies. Currently, there is no imaging biomarker suitable for a definitive early diagnosis of α-synucleinopathies. Although dopaminergic deficits detected with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) radiotracers can support clinical diagnosis by confirming the presence of dopaminergic neurodegeneration, dopaminergic imaging cannot visualize the preceding disease process, nor distinguish α-synucleinopathies from tauopathies with dopaminergic neurodegeneration, especially at early symptomatic disease stage when clinical presentation is often overlapping. Aggregated α-synuclein (αSyn) could be a suitable imaging biomarker in α-synucleinopathies, because αSyn aggregation and therefore, Lewy pathology is evidently an early driver of α-synucleinopathies pathogenesis. Additionally, several antibodies and small molecule compounds targeting aggregated αSyn are in development for therapy. However, there is no way to directly measure if or how much they lower the levels of aggregated αSyn in the brain. There is clearly a paramount diagnostic and therapeutic unmet medical need. To date, aggregated αSyn and Lewy pathology inclusion bodies cannot be assessed ante-mortem with SPECT or PET imaging because of the suboptimal binding characteristics and/or physicochemical properties of current radiotracers. The aim of this narrative review is to highlight the suitability of aggregated αSyn as an imaging biomarker in α-synucleinopathies, the current limitations with and lessons learned from αSyn radiotracer development, and finally to propose antibody-based ligands for imaging αSyn aggregates as a complementary tool rather than an alternative to small molecule ligands. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.  相似文献   
10.
Coronary artery disease is the number-one killer in developed countries, with lifetime prevalence of up to 50% in American men, and is the topic of much medical literature. Recently, multiple therapies have emerged to save lives after acute myocardial infarction (AMI), backed by well-conducted studies; however, appropriate implementation of therapy guidelines is less than optimal. Recent efforts have focused on improving the quality of care (QC) after AMI in order to improve outcomes. This article illustrates how outcome after AMI is related to QC, describes the underuse of evidence-based therapies, and discusses factors associated with poor guideline adherence. It also reviews current quality improvement projects, and some available means to measure and optimize the QC for patients with AMI.  相似文献   
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