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1.
Phys Rev Lett ; 128(13): 132501, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426696

RESUMEN

We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst) ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010 GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157 GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15 fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15 fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.

2.
Artículo en Inglés | MEDLINE | ID: mdl-35850503

RESUMEN

Summary: Objective. To reduce the omalizumab dose in patients with allergic bronchopulmonary aspergillosis (ABPA) who were on long-term omalizumab treatment. Methods. Once asthma was controlled, two approaches were used to reduce total monthly omalizumab dose, 1) both extending dose intervals from 2 to 4 weeks and decrease omalizumab dose, 2) to reduce omalizumab dose while keeping dose intervals stable. Results. Thirteen patients with ABPA (8F/5M, mean age 53.4 ± 13.0 years) were included. Pre-omalizumab, mean blood eosinophil count was 723.1 ± 547.1 cells/mcL, mean numbers of attacks and hospitalizations were 2.5 ± 1.5 and 1.3 ± 0.8, respectively. Median total monthly omalizumab dose was 750 (min 300, max 900) mg. First and 2nd approach to reduce omalizumab dose was used in nine and four patients with a median time of reduction 32 (min 13, max 47) months. The 2nd dose reduction was made in four patients at median of 23.5 months. Pre-omalizumab, mean oral corticosteroid (OCS, as methylprednisolone) dose was 12.2 ± 10.4 mg daily, it decreased to 0.69 ± 0.95 mg (p = 0.001) in the 1st year of omalizumab and could be stopped in 11 patients. Attacks and hospitalizations decreased to 0.31 ± 0.86 (p less than 0.001) and 0 (p = 0.003), respectively, in the 1st year of omalizumab. Total omalizumab dose was reduced by median 40% (min 20, max 60) in 1st intervention and 50% (min 20, max 67) after 2nd intervention. After omalizumab reduction, asthma control did not deteriorate and there was no need to increase the omalizumab or OCS-dose. Conclusions. Decreasing the total omalizumab dose does not cause clinical deterioration in ABPA after the disease is controlled.

3.
Niger J Clin Pract ; 24(3): 425-434, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33723119

RESUMEN

OBJECTIVE: This study aimed to compare the clinical efficacy and survival rates of the hall technique (HT), and conventional restoration (CR) for the management of occlusoproximal carious lesions in primary molars. MATERIALS AND METHODS: This clinical study observed 35 children (aged 4-8 years). Exclusion criteria included symptoms of pulpal or periradicular pathology or systemic conditions requiring special dental considerations. For each child, at least one tooth was treated with HT and one with CR. The primary outcome measures were minor and major clinical failure rates. Plaque and gingival scores of the teeth were also evaluated. Friedman test and Wilcoxon signed ranks test were used to compare the plaque and gingival index scores for each arm. Chi-square tests were used for comparisons of clinical outcomes, plaque-gingival index, and distribution of ICDAS categories among treatment arms (P < 0.05). RESULTS: Thirty-three of 35 (94.2%) participants returned for 1-year follow-up. HT showed statistically significantly higher treatment survival rate and fewer minor failures than CR (P = 0.040). The rate of major failures was minimal (2 of 84 teeth) and did not differ between treatments (P = 0.092). In both treatment groups, the gingival score and plaque score were significantly decreased at the 1-year follow-up (P < 0.05). CONCLUSION: HT was a more successful method for managing caries in primary molars than CR, both for symptoms of pulpal disease and longevity of the restorations. HT is a simplified method of managing carious primary molars using SSCs cemented with no local anesthesia, caries removal, or tooth preparation.


Asunto(s)
Caries Dental , Acero Inoxidable , Niño , Preescolar , Coronas , Caries Dental/terapia , Susceptibilidad a Caries Dentarias , Restauración Dental Permanente , Humanos , Diente Molar , Diente Primario
4.
Phys Rev Lett ; 125(11): 112502, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32976004

RESUMEN

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.

5.
Genetica ; 145(4-5): 341-350, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28567603

RESUMEN

The Cimbicidae is a small family of the primitive and relatively less diverse suborder Symphyta (Hymenoptera). Here, nearly complete mitochondrial genome (mitogenome) of hairy sawfly, Corynis lateralis (Hymenoptera: Cimbicidae) was sequenced using next generation sequencing and comparatively analysed with the mitogenome of Trichiosoma anthracinum. The sequenced length of C. lateralis mitogenome was 14,899 bp with an A+T content of 80.60%. All protein coding genes (PCGs) are initiated by ATN codons and all are terminated with TAR or T- stop codon. All tRNA genes preferred usual anticodons. Compared with the inferred insect ancestral mitogenome, two tRNA rearrangements were observed in the IQM and ARNS1EF gene clusters, representing a new event not previously reported in Symphyta. An illicit priming of replication and/or intra/inter-mitochondrial recombination and TDRL seem to be responsible mechanisms for the rearrangement events in these gene clusters. Phylogenetic analyses confirmed the position of Corynis within Cimbicidae and recovered a relationship of Tenthredinoidea + (Cephoidea + Orussoidea) in Symphyta.


Asunto(s)
Genes de Insecto , Genoma Mitocondrial , Himenópteros/genética , Familia de Multigenes , Animales , Codón , Himenópteros/clasificación , Proteínas de Insectos/genética , Filogenia , ARN Ribosómico/genética , ARN de Transferencia/genética , Análisis de Secuencia de ADN
6.
Proteins ; 84(1): 172-189, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26573747

RESUMEN

Sarcomeric myosins have the remarkable ability to form regular bipolar thick filaments that, together with actin thin filaments, constitute the fundamental contractile unit of skeletal and cardiac muscle. This has been established for over 50 years and yet a molecular model for the thick filament has not been attained. In part this is due to the lack of a detailed molecular model for the coiled-coil that constitutes the myosin rod. The ability to self-assemble resides in the C-terminal section of myosin known as light meromyosin (LMM) which exhibits strong salt-dependent aggregation that has inhibited structural studies. Here we evaluate the feasibility of generating a complete model for the myosin rod by combining overlapping structures of five sections of coiled-coil covering 164 amino acid residues which constitute 20% of LMM. Each section contains ∼ 7-9 heptads of myosin. The problem of aggregation was overcome by incorporating the globular folding domains, Gp7 and Xrcc4 which enhance crystallization. The effect of these domains on the stability and conformation of the myosin rod was examined through biophysical studies and overlapping structures. In addition, a computational approach was developed to combine the sections into a contiguous model. The structures were aligned, trimmed to form a contiguous model, and simulated for >700 ns to remove the discontinuities and achieve an equilibrated conformation that represents the native state. This experimental and computational strategy lays the foundation for building a model for the entire myosin rod.


Asunto(s)
Subfragmentos de Miosina/química , Secuencia de Aminoácidos , Cardiomiopatías/genética , Cristalografía por Rayos X , Humanos , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Mutación , Subfragmentos de Miosina/genética , Conformación Proteica , Estabilidad Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Temperatura
7.
Phys Rev Lett ; 111(14): 141803, 2013 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-24152148

RESUMEN

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 µA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.

8.
Zootaxa ; 3750: 37-56, 2013 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-25113676

RESUMEN

Psorodonotus (Orthoptera, Tettigoniidae) includes 11 species distributed in Caucasus, Anatolia and Balkans. Although its present taxonomy is problematic, mainly three species groups can be distinguished; (i) The Specularis Group, (ii) The Caucasicus Group and (iii) The Venosus Group. Our recent studies on the genus have revealed presence of two new species in the last species group. Morphology of the species group studied both qualitatively and quantitatively using linear metric data of pronotum, tegmina and hind femur, and geometric data of male cerci and ovipositor. Morphological data were accompanied by data obtained from male calling song. Morphological and song data were produced from six different populations from North and Eastern part of Turkey: (1) Hakkari, (2) Tendürek, (3) Giresun, (4) Artvin, (5) Kars and (6) Agri. Qualitative and quantitative morphology, either linear-metric or geometric, suggest last three population as members of the same unit, but each of other three as different units. Song data are also largely in support of the morphological results. Necessary illustrations were provided to document results visually. Following conclusions were made: (1) the Artvin, Kars and Agri populations represent typical P. venosus and the Giresun population P. rugulosus, (2) each of the Hakkari and Tendürek populations represents a new species and P. hakkari sp. n. and P. tendurek sp. n. described by comparing with other members of P. venosus group, (3) P. rugulosus, P. hakkari sp. n. and P. tendurek sp. n. differ from P. venosus mainly by the longer cerci (extend to or beyond end of abdomen) and indistinct tubercles on surface of pronotal disc in female. P. rugulosus and P. tendurek sp. n. are also similar by sharing presence of two loud elements in a syllable (one in P. venosus, song of P. hakkari sp. n. is not available). But, similarities in phenotype are in conflict with relationships suggested by genetic data. 


Asunto(s)
Ortópteros/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Animales , Peninsula Balcánica , Femenino , Masculino , Ortópteros/anatomía & histología , Ortópteros/fisiología , Turquía , Vocalización Animal
9.
Eur Rev Med Pharmacol Sci ; 27(18): 8877-8888, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37782196

RESUMEN

OBJECTIVE: The objective of our study was to evaluate whether ovarian suppression by two different hormonal methods may spare the ovary the cytotoxic effects of isotretinoin in a rat model. MATERIALS AND METHODS: Four groups (n=8 Sprague-Dawley albino rats per group) were studied: control (Group I), 7.5 mg/kg/day isotretinoin (Group II), isotretinoin plus the combination of 0.030 mg ethinyl estradiol/0.15 mg levonorgestrel (combined oral contraceptive, COC), and isotretinoin plus 100 µg (microgram) leuprolide acetate (GnRHa) (Group III and IV, respectively). Four rats from each group were decapitated on the 30th day of treatment, and the remaining rats were decapitated on the 30th day of untreated follow-up. Serum anti-Mullerian hormone (AMH) concentrations, healthy and atretic follicle numbers, and apoptotic activity of follicles in oophorectomy specimens were compared between the groups. RESULTS: There were no significant differences in AMH levels among the study groups before, immediately after (first month), and one month after their last medication (second month) (p=0.08, 0.47, and 0.08, respectively). At the end of the first month, the control group had a higher median count of healthy primordial follicles compared to the study groups: 13.5 (8-22), 5.5 (3-11), 6 (2-13), and 1 (0-1) in control, isotretinoin, isotretinoin+COC, and isotretinoin+GnRHa groups, respectively (p=0.02). However, there was no statistically significant difference in the number of healthy primordial follicles between the groups one month after the last medication (p=0.33). The median atretic antral follicle counts in the first month were 2 (1-4), 3.5 (1-4), 0 (0-2), and 0 (0-0) in the control, isotretinoin, isotretinoin+COC, and isotretinoin+GnRHa groups, respectively (p=0.02). Otherwise, there were no significant differences in other types of follicles among the control and treated groups (p>0.05). There was also no statistical difference between the groups regarding immunostaining intensity for active caspase-3 evaluated in the first or second month of treatment (p=0.8 and 0.2, respectively). CONCLUSIONS: Our results show that GnRH agonists or COC have no protective effects on ovarian reserve when co-administered with isotretinoin in the rat model.


Asunto(s)
Anticonceptivos Orales , Reserva Ovárica , Femenino , Ratas , Animales , Humanos , Isotretinoína/farmacología , Ratas Sprague-Dawley , Hormona Antimülleriana , Factores Inmunológicos , Hormona Liberadora de Gonadotropina
10.
Gene ; 576(1 Pt 3): 404-11, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26515518

RESUMEN

Two complete mitogenomes of the stem borers, Calameuta filiformis and Calameuta idolon, and the complete A+T-rich region of Trachelus iudaicus (Hymenoptera: Cephidae), are reported. The mitogenomes of these species are the longest reported from hymenopterans to date. A remarkable increase in length of the A+T-rich region, the longest for Hymenoptera, was found and compared across the tribe Cephini. The presence of the tRNA- and rRNA-like sequences were reported in the A+T-rich region of sawflies and they were suggested to play a role in replication and/or transcription. The long and short tandem repeats were orderly located in both sides of the A+T-rich region producing stable secondary structures. We suggest that the short tandem repeats are likely to function as a replication fork barrier.


Asunto(s)
Adenina/química , Genes de Insecto , Genoma Mitocondrial , Himenópteros/genética , Timina/química , Animales , Composición de Base
11.
Protein Sci ; 25(2): 456-71, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26506216

RESUMEN

Ubiquitin (Ub) chains regulate a wide range of biological processes, and Ub chain connectivity is a critical determinant of the many regulatory roles that this post-translational modification plays in cells. To understand how distinct Ub chains orchestrate different biochemical events, we and other investigators have developed enzymatic and non-enzymatic methods to synthesize Ub chains of well-defined length and connectivity. A number of chemical approaches have been used to generate Ub oligomers connected by non-native linkages; however, few studies have examined the extent to which non-native linkages recapitulate the structural and functional properties associated with native isopeptide bonds. Here, we compare the structure and function of Ub dimers bearing native and non-native linkages. Using small-angle X-ray scattering (SAXS) analysis, we show that scattering profiles for the two types of dimers are similar. Moreover, using an experimental structural library and atomistic simulations to fit the experimental SAXS profiles, we find that the two types of Ub dimers can be matched to analogous structures. An important application of non-native Ub oligomers is to probe the activity and selectivity of deubiquitinases. Through steady-state kinetic analyses, we demonstrate that different families of deubiquitinases hydrolyze native and non-native isopeptide linkages with comparable efficiency and selectivity. Considering the significant challenges associated with building topologically diverse native Ub chains, our results illustrate that chains harboring non-native linkages can serve as surrogate substrates for explorations of Ub function.


Asunto(s)
Ubiquitina/química , Animales , Bases de Datos de Proteínas , Humanos , Hidrólisis , Modelos Moleculares , Conformación Proteica , Multimerización de Proteína , Dispersión del Ángulo Pequeño , Ubiquitina/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Difracción de Rayos X
12.
Cent Eur J Public Health ; 13(2): 96-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15969458

RESUMEN

To determine whether there is a relationship between trichomoniasis and bacterial vaginosis (BV), cervicovaginal smears obtained from 600 women were stained with the Papanicolaou technique and examined cytologically. Thirty-six (6%) of 600 women were diagnosed as having Trichomonas vaginalis [TV(+)]. Sixteen (44.4%) of 36 TV(+) cases were observed as having BV [BV(+)]. Thirty-one of 564 TV(-) vaginal smears were also positive for BV (5.5%). There was a statistically significant correlation between trichomoniasis and bacterial vaginosis (p < 0.05). It is possible that TV might create an anaerobic environment, thereby changing the vaginal flora. This flora becomes a more suitable milieu for growing of anaerobic microorganisms. It can be postulated that TV might be the most important protozoan that contributes to the overgrowth of BV-related microorganisms.


Asunto(s)
Prueba de Papanicolaou , Tricomoniasis/complicaciones , Frotis Vaginal , Vaginosis Bacteriana/complicaciones , Animales , Femenino , Humanos , Tricomoniasis/fisiopatología , Turquía , Vaginosis Bacteriana/fisiopatología
13.
Phys Rev Lett ; 85(7): 1388-91, 2000 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-10970511

RESUMEN

Cross sections for quasifree Compton scattering from the deuteron were measured for incident energies of E(gamma) = 236-260 MeV at the laboratory angle straight theta(gamma(')) = -135 degrees. The recoil nucleons were detected in a liquid-scintillator array situated at straight theta(N) = 20 degrees. The measured differential cross sections were used, with the calculations of Levchuk et al., to determine the polarizabilities of the bound nucleons. For the bound proton, the extracted values were consistent with the accepted value for the free proton. Combining our results for the bound neutron with those from Rose et al., we obtain 1-sigma constraints of alpha;(n) = 7.6-14.0 and beta;(n) = 1.2-7.6.

14.
Br J Ophthalmol ; 83(1): 50-3, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10209435

RESUMEN

AIMS: To determine whether an increase in vascular resistance in the central retinal and ophthalmic arterial circulations contributes to the development of central retinal vein occlusion (CRVO), or haemodynamic alterations in central retinal and ophthalmic arteries occur secondary to the vein occlusion as increased intravascular pressure is transferred through the capillary bed to the arterial side and the effect of panretinal photocoagulation treatment on these circulations in ischaemic cases. METHODS: The ophthalmic and central retinal arteries of the affected and non-affected eyes of 20 patients with non-ischaemic CRVO, 13 patients with ischaemic CRVO, and 22 control subjects were investigated by colour Doppler imaging. Panretinal photocoagulation (PRP) treatment was applied to the eyes with ischaemic CRVO. Maximum and minimum blood flow velocities, and resistivity indexes were calculated in the affected and healthy eyes of patients and in the control eyes. RESULTS: Average blood flow velocity in the central retinal and ophthalmic arteries of patients with non-ischaemic CRVO did not differ from their fellow eyes, but a significantly lower average blood flow velocity was found in the ophthalmic and central retinal arteries of the patients with ischaemic CRVO compared with their fellow eyes. Patients with ischaemic CRVO had significantly lower blood flow velocities in their ophthalmic and central retinal arteries than non-ischaemic cases that were further reduced following PRP treatment. CONCLUSION: This study suggests that impaired arterial blood flow observed in patients with CRVO may be partly related to secondary changes in the retrobulbar arterial circulation as a result of enhanced arterial resistance following CRVO. These data also demonstrate that PRP treatment decreases retinal and ophthalmic blood flow velocities in patients with ischaemic CRVO.


Asunto(s)
Fotocoagulación/métodos , Oclusión de la Vena Retiniana/cirugía , Velocidad del Flujo Sanguíneo , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Arteria Retiniana/fisiopatología , Oclusión de la Vena Retiniana/fisiopatología , Ultrasonografía Doppler en Color , Resistencia Vascular
15.
Zookeys ; (130): 363-78, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22259289

RESUMEN

Cephinae is traditionally divided into three tribes and about 24 genera based on morphology and host utilization. There has been no study testing the monophyly of taxa under a strict phylogenetic criterion. A molecular phylogeny of Cephinae based on a total of 68 sequences of mtDNA COI gene, representing seven genera of Cephinae, is reconstructed to test the traditional limits and relationships of taxa. Monophyly of the traditional tribes is not supported. Monophyly of the genera are largely supported except for Pachycephus. A few host shift events are suggested based on phylogenetic relationships among taxa. These results indicate that a more robust phylogeny is required for a more plausible conclusion. We also report two species of Cephus for the first time from Turkey.

16.
Phys Rev Lett ; 58(8): 840, 1987 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-10035050
20.
Phys Rev Lett ; 99(9): 092301, 2007 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-17930999

RESUMEN

We have measured the beam-normal single-spin asymmetry in elastic scattering of transversely polarized 3 GeV electrons from unpolarized protons at Q2=0.15, 0.25 (GeV/c)2. The results are inconsistent with calculations solely using the elastic nucleon intermediate state and generally agree with calculations with significant inelastic hadronic intermediate state contributions. A(n) provides a direct probe of the imaginary component of the 2gamma exchange amplitude, the complete description of which is important in the interpretation of data from precision electron-scattering experiments.

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