Correspondence: No substantial long-term bias in the Cenozoic benthic foraminifera oxygen-isotope record

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Stability and aromaticity of nH2@B12N12 (n=1–12) clusters

Standard ab initio and density functional calculations are carried out to determine the structure, stability, and reactivity of B12N12 clusters with hydrogen doping. To lend additional support, conceptual DFT-based reactivity descriptors and the associated electronic structure principles are also used. Related cage aromaticity of this B12N12 and nH2@B12N12 are analyzed through the nucleus independent chemical shift values

Chromosome assignment of two cloned DNA probes hybridizing predominantly to human sex chromosomes

In situ hybridization experiments were carried out with two clones, YACG 35 and 2.8, which had been selected from two genomic libraries strongly enriched for the human Y chromosome. Besides the human Y chromosome, both sequences strongly hybridized to the human X chromosome, with few minor binding sites on autosomes. In particular, on the X chromosome DNA from clone YACG 35 hybridized to the centromeric region and the distal part of the short arm (Xp2.2). On the Y chromosome, the sequence was assigned to one site situated in the border region between Yq1.1 and Yq1.2. DNA from clone 2.8 also hybridized to the centromeric region of the X and the distal part of the short arm (Xq2.2). On the Y, however, two binding sites were observed (Yp1.1 and Yq1.2). The findings indicate that sex chromosomal sequences may be localized in homologous regions (as suggested from meiotic pairing) but also at ectopic sites

The Role of Eif6 in Skeletal Muscle Homeostasis Revealed by Endurance Training Co-expression Networks

Regular endurance training improves muscle oxidative capacity and reduces the risk of age-related disorders. Understanding the molecular networks underlying this phenomenon is crucial. Here, by exploiting the power of computational modeling, we show that endurance training induces profound changes in gene regulatory networks linking signaling and selective control of translation to energy metabolism and tissue remodeling. We discovered that knockdown of the mTOR-independent factor Eif6, which we predicted to be a key regulator of this process, affects mitochondrial respiration efficiency, ROS production, and exercise performance. Our work demonstrates the validity of a data-driven approach to understanding muscle homeostasis

Visual fields in patients who have undergone vitrectomy for complications of diabetic retinopathy. A prospective study

BACKROUND: To determine the extent of visual field loss in patients who had required a pars plana vitrectomy secondary to complications of proliferative diabetic retinopathy. METHODS: Patients that had undergone a vitrectomy on at least one eye for treatment of either vitreous haemorrhage or tractional retinal detachment were selected for study. ETDRS acuity and Humphrey binocular Esterman visual field testing were performed and compared to the minimum standards for safe driving as defined by the Royal College of Ophthalmologists in 1999. In addition to this Goldman kinetic visual fields using a III4e and V4e stimulus size and central 24-2 threshold test with the SITA-fast strategy were performed on the vitrectomised eye. RESULTS: 20 patients (n = 20) were recruited. Mean visual acuity in the eye being tested was 0.20 (Snellen 6/9.5). Results from the Humphrey field analyzer showed a mean number of abnormal stimulus locations of 71.2% (p < 0.005). 70% of patients had sufficient binocular acuity to drive and of these 71.4% were shown not to have a minimum visual field for safe driving on binocular Esterman field analysis. CONCLUSION: Vitrectomy potentially allows retention/restoration of good visual acuity in patients with complications of proliferative diabetic retinopathy. However patients may be suffering from unrecognized visual impairment consequent upon extensive visual field loss which in over two thirds of patients may be sufficiently severe to preclude safe driving

Hereditary sensory and autonomic neuropathies: types II, III, and IV

The hereditary sensory and autonomic neuropathies (HSAN) encompass a number of inherited disorders that are associated with sensory dysfunction (depressed reflexes, altered pain and temperature perception) and varying degrees of autonomic dysfunction (gastroesophageal reflux, postural hypotention, excessive sweating). Subsequent to the numerical classification of four distinct forms of HSAN that was proposed by Dyck and Ohta, additional entities continue to be described, so that identification and classification are ongoing. As a group, the HSAN are rare diseases that affect both sexes. HSAN III is almost exclusive to individuals of Eastern European Jewish extraction, with incidence of 1 per 3600 live births. Several hundred cases with HSAN IV have been reported. The worldwide prevalence of HSAN type II is very low. This review focuses on the description of three of the disorders, HSAN II through IV, that are characterized by autosomal recessive inheritance and onset at birth. These three forms of HSAN have been the most intensively studied, especially familial dysautonomia (Riley-Day syndrome or HSAN III), which is often used as a prototype for comparison to the other HSAN. Each HSAN disorder is likely caused by different genetic errors that affect specific aspects of small fiber neurodevelopment, which result in variable phenotypic expression. As genetic tests are routinely used for diagnostic confirmation of HSAN III only, other means of differentiating between the disorders is necessary. Diagnosis is based on the clinical features, the degree of both sensory and autonomic dysfunction, and biochemical evaluations, with pathologic examinations serving to further confirm differences. Treatments for all these disorders are supportive

Epidemiology of cardiovascular risk factors in Greece: aims, design and baseline characteristics of the ATTICA study

BACKGROUND: In an attempt to evaluate the levels of several cardiovascular risk factors in Greece we conducted a population-based health and nutrition survey, the "ATTICA study". In this work we present the design and the methodology of the study, as well as the status of various baseline characteristics of the participants. METHODS: From May 2001 to December 2002 we randomly enrolled 1514 adult men and 1528 adult women, stratified by age – gender (census 2000), from the greater area of Athens. More than 300 demographic, lifestyle, behavioral, dietary, clinical and biochemical variables have been recorded. RESULTS: Regarding the frequency of the classical cardiovascular risk factors we observed that 51% of men and 39% of women reported smokers (p < 0.05), 37% of men and 25% of women were defined as hypertensives (p < 0.05), 46% of men and 40% of women had total serum cholesterol levels above 200 mg/dl (p < 0.05) and 8% of men and 6% of women had history of diabetes mellitus. Moreover, 20% of men and 15% of women were obese (p < 0.05), while men were more physically active as compared to women (42% vs. 39%, p < 0.05). 19% of men and 38% of women had mild to severe depressive symptoms (p < 0.01). Finally, 72 men (5%) and 45 (3%) women reported history of coronary heart disease at entry evaluation. CONCLUSIONS: The prevalence of the common cardiovascular risk factors in our population seems high. As a consequence a considerable proportion of Greek adults are at "high-risk" for future cardiovascular events

Retinal Degeneration Progression Changes Lentiviral Vector Cell Targeting in the Retina

In normal mice, the lentiviral vector (LV) is very efficient to target the RPE cells, but transduces retinal neurons well only during development. In the present study, the tropism of LV has been investigated in the degenerating retina of mice, knowing that the retina structure changes during degeneration. We postulated that the viral transduction would be increased by the alteration of the outer limiting membrane (OLM). Two different LV pseudotypes were tested using the VSVG and the Mokola envelopes, as well as two animal models of retinal degeneration: light-damaged Balb-C and Rhodopsin knockout (Rho-/-) mice. After light damage, the OLM is altered and no significant increase of the number of transduced photoreceptors can be obtained with a LV-VSVG-Rhop-GFP vector. In the Rho-/- mice, an alteration of the OLM was also observed, but the possibility of transducing photoreceptors was decreased, probably by ongoing gliosis. The use of a ubiquitous promoter allows better photoreceptor transduction, suggesting that photoreceptor-specific promoter activity changes during late stages of photoreceptor degeneration. However, the number of targeted photoreceptors remains low. In contrast, LV pseudotyped with the Mokola envelope allows a wide dispersion of the vector into the retina (corresponding to the injection bleb) with preferential targeting of Müller cells, a situation which does not occur in the wild-type retina. Mokola-pseudotyped lentiviral vectors may serve to engineer these glial cells to deliver secreted therapeutic factors to a diseased area of the retina

Turing Patterns Inside Cells

Concentration gradients inside cells are involved in key processes such as cell division and morphogenesis. Here we show that a model of the enzymatic step catalized by phosphofructokinase (PFK), a step which is responsible for the appearance of homogeneous oscillations in the glycolytic pathway, displays Turing patterns with an intrinsic length-scale that is smaller than a typical cell size. All the parameter values are fully consistent with classic experiments on glycolytic oscillations and equal diffusion coefficients are assumed for ATP and ADP. We identify the enzyme concentration and the glycolytic flux as the possible regulators of the pattern. To the best of our knowledge, this is the first closed example of Turing pattern formation in a model of a vital step of the cell metabolism, with a built-in mechanism for changing the diffusion length of the reactants, and with parameter values that are compatible with experiments. Turing patterns inside cells could provide a check-point that combines mechanical and biochemical information to trigger events during the cell division process