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Multiple sclerosis susceptibility alleles in African Americans.
Multiple sclerosis (MS) is an autoimmune demyelinating disease characterized by complex genetics and multifaceted gene-environment interactions. Compared to whites, African Americans have a lower risk for developing MS, but African Americans with MS have a greater risk of disability. These differences between African Americans and whites may represent differences in genetic susceptibility and/or environmental factors. SNPs from 12 candidate genes have recently been identified and validated with MS risk in white populations. We performed a replication study using 918 cases and 656 unrelated controls to test whether these candidate genes are also associated with MS risk in African Americans. CD6, CLEC16a, EVI5, GPC5, and TYK2 contained SNPs that are associated with MS risk in the African American data set. EVI5 showed the strongest association outside the major histocompatibility complex (rs10735781, OR=1.233, 95% CI=1.06-1.43, P-value=0.006). In addition, RGS1 seems to affect age of onset whereas TNFRSF1A seems to be associated with disease progression. None of the tested variants showed results that were statistically inconsistent with the effects established in whites. The results are consistent with shared disease genetic mechanisms among individuals of European and African ancestry
Additive effects of beta-alanine and sodium bicarbonate on high-intensity upper-body intermittent performance
We examined the isolated and combined effects of beta-alanine (BA) and sodium bicarbonate (SB) on high-intensity intermittent upper-body performance in judo and jiu-jitsu competitors. 37 athletes were assigned to one of four groups: (1) placebo (PL)+PL; (2) BA+PL; (3) PL+SB or (4) BA+SB. BA or dextrose (placebo) = (6.4 g day-1) was ingested for 4 weeks and 500 mg kg-1 BM of SB or calcium carbonate (placebo) was ingested for 7 days during the 4th week. Before and after 4 weeks of supplementation, the athletes completed four 30-s upper-body Wingate tests, separated by 3 min. Blood lactate was determined at rest, immediately after and 5 min after the 4th exercise bout, with perceived exertion reported immediately after the 4th bout. BA and SB alone increased the total work done in +7 and 8 %, respectively. The co-ingestion resulted in an additive effect (+14 %, p < 0.05 vs. BA and SB alone). BA alone significantly improved mean power in the 2nd and 3rd bouts and tended to improve the 4th bout. SB alone significantly improved mean power in the 4th bout and tended to improve in the 2nd and 3rd bouts. BA+SB enhanced mean power in all four bouts. PL+PL did not elicit any alteration on mean and peak power. Post-exercise blood lactate increased with all treatments except with PL+PL. Only BA+ SB resulted in lower ratings of perceived exertion (p = 0.05). Chronic BA and SB supplementation alone equally enhanced high-intensity intermittent upper-body performance in well-trained athletes. Combined BA and SB promoted a clear additive ergogenic effect
Coherent coupling between radio frequency, optical, and acoustic waves in piezo-optomechanical circuits
The interaction of optical and mechanical modes in nanoscale optomechanical
systems has been widely studied for applications ranging from sensing to
quantum information science. Here, we develop a platform for cavity
optomechanical circuits in which localized and interacting 1550 nm photons and
2.4 GHz phonons are combined with photonic and phononic waveguides. Working in
GaAs facilitates manipulation of the localized mechanical mode either with a
radio frequency field through the piezo-electric effect, or optically through
the strong photoelastic effect. We use this to demonstrate a novel acoustic
wave interference effect, analogous to coherent population trapping in atomic
systems, in which the coherent mechanical motion induced by the electrical
drive can be completely cancelled out by the optically-driven motion. The
ability to manipulate cavity optomechanical systems with equal facility through
either photonic or phononic channels enables new device and system
architectures for signal transduction between the optical, electrical, and
mechanical domains
Clinical and histologic features of botryoid odontogenic cyst: a case report
<p>Abstract</p> <p>Introduction</p> <p>The lateral periodontal cyst, as the name implies, occurs on a lateral periodontal location and is of developmental origin, arising from cystic degeneration of clear cells of the dental lamina. A botryoid odontogenic cyst is considered to be a rare multilocular variant of a lateral periodontal cyst.</p> <p>Case presentation</p> <p>We report the clinical and histopathologic features of a rare case of botryoid odontogenic cyst found in an edentulous area corresponding to the right lower canine of a 64-year-old African-American woman. A multilocular radiolucency was observed, and surgical removal of the lesion revealed a nodule of rubber-like consistency measuring about 1.5 cm in diameter. Cross-sectioning of the nodule showed that it consisted of various cystic compartments. Histologically, various voluminous periodic acid-Schiff-negative clear cells randomly distributed throughout the cystic epithelium were observed, as well as cell layers showing thickenings generally formed by oval, sometimes entangled plaques. The capsule consisted of fibrous connective tissue and showed rare and discrete foci of a perivascular mononuclear inflammatory infiltrate and reactive bone-tissue fragments. The final diagnosis was botryoid odontogenic cyst.</p> <p>Conclusion</p> <p>We provide data that allow the reader to establish the differences between botryoid odontogenic cyst, glandular odontogenic cyst, and lateral periodontal cyst, helping with the differential diagnosis. The reader will have the opportunity to review botryoid odontogenic cyst clinical and histopathologic features, including treatment.</p
Flavour physics constraints in the BMSSM
We study the implications of the presence of the two leading-order,
non-renormalizable operators in the Higgs sector of the MSSM to flavour physics
observables. We identify the constraints of flavour physics on the parameters
of the BMSSM when we: a) focus on a region of parameters for which electroweak
baryogenesis is feasible, b) use a CMSSM-like parametrization, and c) consider
the case of a generic NUHM-type model. We find significant differences as
compared to the standard MSSM case.Comment: 22 pages, 7 figure
The use of full-setting non-invasive ventilation in the home care of people with amyotrophic lateral sclerosis-motor neuron disease with end-stage respiratory muscle failure: a case series
<p>Abstract</p> <p>Introduction</p> <p>Little has been written about the use of non-invasive ventilation in the home care of amyotrophic lateral sclerosis-motor neuron disease patients with end-stage respiratory muscle failure. Nocturnal use of non-invasive ventilation has been reported to improve daytime blood gases but continuous non-invasive ventilation dependence has not been studied in this regard. There continues to be great variation by country, economics, physician interest and experience, local concepts of palliation, hospice requirements, and resources available for home care. We report a case series of home-based amyotrophic lateral sclerosis-motor neuron disease patients who refused tracheostomy and advanced non-invasive ventilation to full-setting, while maintaining normal alveolar ventilation and oxygenation in the course of the disease. Since this topic has been presented in only one center in the United States and nowhere else, it is appropriate to demonstrate that this can be done in other countries as well.</p> <p>Case presentation</p> <p>We present here the cases of three Caucasian patients (a 51-year-old Caucasian man, a 45-year-old Caucasian woman and a 57-year-old Caucasian woman) with amyotrophic lateral sclerosis who developed continuous non-invasive ventilation dependence for 15 to 27 months without major complications and were able to maintain normal CO<sub>2 </sub>and pulse oxyhemoglobin saturation despite a non-measurable vital capacity. All patients were wheelchair-dependent and receiving riluzole 50 mg twice a day. Patient one developed mild-to-moderate bulbar-innervated muscle weakness. He refused tracheostomy but accepted percutaneous gastrostomy. Patient two had two lung infections, acute bronchitis and pneumonia, which were treated with antibiotics and cough assistance at home. Patient three had three chest infections (bronchitis and pneumonias) and asthmatic episodes treated with antibiotics, bronchodilators and cough assistance at home. All patients had normal speech while receiving positive pressure; they died suddenly and with normal oxygen saturation.</p> <p>Conclusions</p> <p>Although warned that prognosis was poor as vital capacity diminished, our patients survived without invasive airway tubes and despite non-measurable vital capacity. No patient opted for tracheostomy. Our patients demonstrate the feasibility of resorting to full-setting non-invasive management to prolong survival, optimizing wellness and management at home, and the chance to die peacefully.</p
Clinical and cost-effectiveness of internal limiting membrane peeling for patients with idiopathic full thickness macular hole. Protocol for a Randomised Controlled Trial : FILMS (Full-thickness macular hole and Internal Limiting Membrane peeling Study)
Background: A full-thickness macular hole (FTMH) is a common retinal condition associated with impaired vision. Randomised controlled trials (RCTs) have demonstrated that surgery, by means of pars plana vitrectomy and post-operative intraocular tamponade with gas, is effective for stage 2, 3 and 4 FTMH. Internal limiting membrane (ILM) peeling has been introduced as an additional surgical manoeuvre to increase the success of the surgery; i.e. increase rates of hole closure and visual improvement. However, little robust evidence exists supporting the superiority of ILM peeling compared with no-peeling techniques. The purpose of FILMS (Fullthickness macular hole and Internal Limiting Membrane peeling Study) is to determine whether ILM peeling improves the visual function, the anatomical closure of FTMH, and the quality of life of patients affected by this disorder, and the cost-effectiveness of the surgery.
Methods/Design: Patients with stage 2–3 idiopathic FTMH of less or equal than 18 months duration (based on symptoms reported by the participant) and with a visual acuity ≤ 20/40 in the study eye will be enrolled in this FILMS from eight sites across the UK and Ireland. Participants will be randomised to receive combined cataract surgery (phacoemulsification and intraocular lens implantation) and pars plana vitrectomy with postoperative intraocular tamponade with gas, with or without ILM peeling. The primary outcome is distance visual acuity at 6 months. Secondary outcomes include distance visual acuity at 3 and 24 months, near visual acuity at 3, 6, and 24 months, contrast sensitivity at 6 months, reading speed at 6 months, anatomical closure of the macular hole at each time point (1, 3, 6, and 24 months), health related quality of life (HRQOL) at six months, costs to the health service and the participant, incremental costs per quality adjusted life year (QALY) and adverse events.
Discussion: FILMS will provide high quality evidence on the role of ILM peeling in FTMH surgery.
Trial registration: This trial is registered with Current Controlled Trials ISRCTN number 33175422 and Clinical Trials.gov identifier NCT00286507.Chief Scientist Office, Scotland (project ref no CZH/4/235), NHS GrampianPeer reviewedPublisher PD
Evolutionary and pulsational properties of white dwarf stars
Abridged. White dwarf stars are the final evolutionary stage of the vast
majority of stars, including our Sun. The study of white dwarfs has potential
applications to different fields of astrophysics. In particular, they can be
used as independent reliable cosmic clocks, and can also provide valuable
information about the fundamental parameters of a wide variety of stellar
populations, like our Galaxy and open and globular clusters. In addition, the
high densities and temperatures characterizing white dwarfs allow to use these
stars as cosmic laboratories for studying physical processes under extreme
conditions that cannot be achieved in terrestrial laboratories. They can be
used to constrain fundamental properties of elementary particles such as axions
and neutrinos, and to study problems related to the variation of fundamental
constants.
In this work, we review the essentials of the physics of white dwarf stars.
Special emphasis is placed on the physical processes that lead to the formation
of white dwarfs as well as on the different energy sources and processes
responsible for chemical abundance changes that occur along their evolution.
Moreover, in the course of their lives, white dwarfs cross different
pulsational instability strips. The existence of these instability strips
provides astronomers with an unique opportunity to peer into their internal
structure that would otherwise remain hidden from observers. We will show that
this allows to measure with unprecedented precision the stellar masses and to
infer their envelope thicknesses, to probe the core chemical stratification,
and to detect rotation rates and magnetic fields. Consequently, in this work,
we also review the pulsational properties of white dwarfs and the most recent
applications of white dwarf asteroseismology.Comment: 85 pages, 28 figures. To be published in The Astronomy and
Astrophysics Revie
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