Mitochondrial genome diversity at the Bering Strait area highlights prehistoric human migrations from Siberia to northern North America

The patterns of prehistoric migrations across the Bering Land Bridge are far from being completely understood: there still exists a significant gap in our knowledge of the population history of former Beringia. Here, through comprehensive survey of mitochondrial DNA genomes retained in ‘relic'' populations, the Maritime Chukchi, Siberian Eskimos, and Commander Aleuts, we explore genetic contribution of prehistoric Siberians/Asians to northwestern Native Americans. Overall, 201 complete mitochondrial sequences (52 new and 149 published) were selected in the reconstruction of trees encompassing mtDNA lineages that are restricted to Coastal Chukotka and Alaska, the Canadian Arctic, Greenland, and the Aleutian chain. Phylogeography of the resulting mtDNA genomes (mitogenomes) considerably extends the range and intrinsic diversity of haplogroups (eg, A2a, A2b, D2a, and D4b1a2a1) that emerged and diversified in postglacial central Beringia, defining independent origins of Neo-Eskimos versus Paleo-Eskimos, Aleuts, and Tlingit (Na-Dene). Specifically, Neo-Eskimos, ancestral to modern Inuit, not only appear to be of the High Arctic origin but also to harbor Altai/Sayan-related ancestry. The occurrence of the haplogroup D2a1b haplotypes in Chukotka (Sireniki) introduces the possibility that the traces of Paleo-Eskimos have not been fully erased by spread of the Neo-Eskimos or their descendants. Our findings are consistent with the recurrent gene flow model of multiple streams of expansions to northern North America from northeastern Eurasia in late Pleistocene–early Holocene.     

High-dose immunosuppressive therapy with autologous hematopoietic stem cell transplantation as a treatment option in multiple sclerosis

High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (auto-HSCT) is a new and promising approach to the treatment of multiple sclerosis (MS) patients because currently there are no effective treatment methods for this disease. In this article, we present results of a prospective clinical study of efficacy of HDIT + auto-HSCT in MS patients. The following treatment strategies were employed in the study: "early," "conventional," and "salvage/late" transplantation. Fifty patients with various types of MS were included in this study. No toxic deaths were reported among 50 MS patients; transplantation procedure was well-tolerated by the patients. The efficacy analysis was performed in 45 patients. Twenty-eight patients achieved an objective improvement of neurological symptoms, defined as at least 0.5-point decrease in the Expanded Disability Status Scale (EDSS) score as compared to the baseline and confirmed during 6 months, and 17 patients had disease stabilization (steady EDSS level as compared to the baseline and confirmed during 6 months). The progression-free survival at 6 years after HDIT + auto-HSCT was 72%. Magnetic resonance imaging data were available in 37 patients before transplantation showing disease activity in 43.3%. No active, new, or enlarging lesions were registered in patients without disease progression. In conclusion, HDIT + auto-HSCT suggests positive results in management of patients with different types of MS. Identification of treatment strategies based on the level of disability, namely "early," "conventional," and "salvage/late" transplantation, appears to be feasible to improve treatment outcomes.     

Assessing Ventilatory Threshold in Individuals With Motor-Complete Spinal Cord Injury

Objective

To assess the feasibility of measuring ventilatory threshold (VT) in higher-level motor-complete spinal cord injury (SCI) using 4 different analysis methods based on noninvasive gas exchange.

Impact of Regular Physical Activity on Adipocytokines and Cardiovascular Characteristics in Spinal Cord–Injured Subjects

Objective

To investigate the relationship of carotid artery intima-media thickness (IMT) and cardiac structure and function with adipocytokines in sedentary (S-SCI) and physically active (PA-SCI) subjects with spinal cord injury (SCI).

Embolic protection devices for carotid artery stenting: better results than stenting without protection?

AIMS: Carotid artery stenting (CAS) for carotid artery stenoses has become an alternative to carotid endarterectomy. However, CAS itself can cause cerebral ischaemic events. Embolic protection devices (PD) promise to reduce the incidence of these events. METHODS AND RESULTS: From July 1996 to March 2003, 1483 patients from 26 hospitals were included in the prospective CAS Registry of the ALKK study group. A PD was used in 668 of 1483 patients (45%). The use of a PD has grown rapidly over the years and reached 100% in 2003. Patients treated with a PD had prior carotid artery dilatation more often (3.5% versus 1%, p < 0.001), a prior myocardial infarction (34% versus 27.4%, p = 0.007) and a history of arterial hypertension (89.9% versus 78.6%, p = 0.007) compared to patients treated without a PD. A thrombus was more often visible in patients treated under distal protection (16.5% versus 8%, p < 0.001). The use of a PD led to a 10-min longer intervention (45 min versus 35 min median, p < 0.001). Patients treated with a PD had a lower rate of ipsilateral stroke (1.7% versus 4.1%, p = 0.007) and a lower rate of all non-fatal strokes and all deaths (2.1% versus 4.9%, p = 0.004) during the hospital stay. This was confirmed by multiple logistic regression analysis (adjusted OR = 0.45, 95% CI: 0.23-0.91, p = 0.026). A similar reduction could be found for symptomatic as well as asymptomatic carotid artery stenoses. CONCLUSION: Since 1996 there has been a steady increase in the use of PDs for CAS, with a 100% use in 2003. The use of a PD may lower the rate of ipsilateral strokes during CAS.     

LDL concentration is correlated with the removal from the plasma of a chylomicron-like emulsion in subjects with coronary artery disease

In animal model studies, the uptake of chylomicron remnants after entering in the space of Disse occurs mainly by low-density lipoprotein (LDL) receptor and LDL receptor-related protein (LRP). In subjects, the relative importance of each one of these receptors for the clearance of chylomicron remnants is not fully understood. In our study, LDL cholesterol and apolipoprotein (apo) B were correlated to the plasma kinetics of a chylomicron-like emulsion in 77 subjects (11 women, mean age 58 +/- 12 years) with coronary artery disease (CAD). Their total cholesterol was 227 +/- 25 mg/dl, triglyceride 159 +/- 25 mg/dl, LDL cholesterol 148 +/- 27 mg/dl, HDL cholesterol 40 +/- 9 mg/dl, apo A1 1.80 +/- 0.53 g/l and apo B 1.65 +/- 0.48 g/l. The emulsion was double-labeled with 3H-triolein and 14C-cholesteryl oleate and injected intravenously after 12-h fasting. The decay curves of the radioisotopes were determined from blood samples collected at predetermined intervals during 60 min. A negative correlation between FCR of the emulsion cholesterol esters and LDL cholesterol and apo B plasma concentrations was found (r=-0.4, P=0.005 and r=-0.3, P=0.01, respectively) whereas FCR of the emulsion triglycerides did not correlate with any of the plasma lipids or apolipoprotein parameters. Concluding, in patients with CAD, LDL catabolic pathway significantly influences the removal from plasma of chylomicron remnants.     

sE‐selectin for stratifying outcome in rheumatoid arthritis

Objectives

To determine the usefulness of sE‐selectin as a marker for early diagnosis and stratification of rheumatoid arthritis.

Methods

We investigated several markers of disease activity, including circulating adhesion molecules and other standard laboratory tests, in a 2–3 year followup analysis of patients with rheumatoid arthritis.

Results

The mean ± SD levels of sE‐selectin (91.68 ± 31.8 ng/ml versus 49.83 ± 14.76 ng/ml) and rheumatoid factor (375.7 ± 394.4 U versus 44.66 ± 37.63 U) were strongly elevated in severe (n = 15) versus mild (n = 7) courses of disease. Statistical calculation of mean and standard deviation revealed that sE‐selectin represents a highly significant marker for the presence of persistent and aggressive disease over time, regardless of therapeutic intervention and observation time points (P = 0.0004). Notably, regression analysis identified constant values for all parameters analyzed and, therefore, a stable course of the disease could be predicted from the beginning.

Conclusion

sE‐selectin appears to be a powerful marker to predict the severity of rheumatoid arthritis.

     

Hypomagnesemia is a frequent finding in the emergency department in patients with chest pain

STUDY OBJECTIVE--To evaluate the frequency of low blood levels of total and ultrafilterable magnesium (total and ultrafilterable hypomagnesemia) in patients with chest pain in the emergency department, and to determine if hypomagnesemia is associated with other clinically important diagnostic and outcome variables in cardiac care. SETTING--An emergency department of a university teaching hospital. DESIGN--Prospective study of extracellular magnesium homeostasis in patients with chest pain in the emergency department and a cohort of patients without chest pain with a clinical indication for blood sampling. PATIENTS--During a 4-month period, 147 patients presenting to the emergency department were studied: 67 patients (mean +/- SD age, 61.4 +/- 13 years) with a chief complaint of chest pain (study group) and 80 patients (55.6 +/- 19 years) with other diagnoses (control group). RESULTS--Total and ultrafilterable hypomagnesemia occurred more frequently in patients with chest pain (20/67 [30%] and 9/67 [13%]) than in the control group (12/80 [15%] and 3/80 [4%]). Patients with a chief complaint of chest pain who were receiving diuretic medications were hypomagnesemic more frequently (9/16 [56%]) than patients not receiving diuretics (12/51 [23%]). In patients with chest pain admitted to the hospital with a diagnosis of "rule out" myocardial infarction, the frequency of hypokalemia was greater among hypomagnesemic patients (6/14 [43%]) than normomagnesemic patients (3/31 [10%]). A similar frequency of hypomagnesemia was noted in patients with a final diagnosis of myocardial infarction (4/15 [27%]) when compared with other patients admitted with chest pain (10/31 [32%]) in whom myocardial infarction was excluded. No association was noted among hypomagnesemia and length of hospital stay or the occurrence of hypotension or dysrhythmias. CONCLUSIONS--Total and ultrafilterable hypomagnesemia are frequent occurrences in patients with and without chest pain in the emergency department. Diuretic use is associated with hypomagnesemia in patients presenting with chest pain in the emergency department. These results support the concept that hypomagnesemia is common in patients with chest pain in the emergency department and is associated with hypokalemia but is not predictive of whether the patient with chest pain has had an acute myocardial infarction.