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101.
The UL41 gene of the HSZP strain of herpes simplex virus type 1 (HSV-1) defective with respect to the early shutoff of host
protein synthesis was sequenced and compared with the corresponding HSV-1 strain KOS and 17 gene sequences. In comparison
with strain 17, nine mutations (base changes) were HSZP specific, five KOS specific and four were common for both strains.
Nine mutations caused codon changes. Three of these mapped to the nonconserved regions and the others to the conserved regions
of the functional map of UL4l gene. One KOS specific mutation mapped to the region responsible for the binding of the virion
host shutoff (vhs) protein to the alpha-transinducing factor (VP16). The possible relationship between mutations and host
shutoff function is discussed. The nucleotide sequence data of the UL41 gene of HSZP and KOS have been submitted to the Genbank
nucleotide database and have been assigned the accesion numbers Z72337 and Z72338.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
102.
Though much research about the public's views of scientists, genetic research and its moral, ethical, and social implications exists, little has been done to investigate how scientists view their own role(s) in public discussions and policy formation related to genetic research and technologies. We interviewed 20 academic geneticists in the United States about their perceptions of the roles they and others (e.g., professional societies, the public, ethicists, and elected officials) do and should play in the formation of science policy, the communication of science to the public, and the public discussions of moral and ethical issues raised by scientific advances. The participants in our study thought that scientists should be more actively involved in public outreach and science policy formation, but frequently they felt ill-equipped and unsupported by their peers and institutions to pursue these activities. Furthermore, many were skeptical of or did not trust elected officials--who they consider uninformed about the issues and too driven by political agendas--to formulate sound science policy. They do, however, have faith in the ability of scientific societies to influence policy effectively, and some thought that societies should play a larger role, both in science policy and as a liaison between scientists and the public. Finally, participants offered suggestions for increasing the involvement and influence of scientists in science-policy formation and public discourse. 相似文献
103.
Cytomegalovirus (CMV) replication in non-proliferating cells requires the coordinated expression of the host enzymes responsible for deoxyribonucleotide synthesis. Thymidylate synthase (TS) is an essential cellular enzyme that catalyzes de novo synthesis of thymidylic acid (dTMP). In this report we show that murine CMV (MCMV) replication and DNA synthesis are inhibited in quiescent 3T6 fibroblasts by raltitrexed, a quinazoline-based folate analog that specifically inhibits TS. This antiviral activity was abrogated in LU3-7 cells, a 3T6 derivative that overproduces TS by about 50-fold. These observations indicate that the anticytomegaloviral activity of raltitrexed is associated with TS inhibition and suggest that cellular TS activity is required for efficient CMV replication in quiescent cells. 相似文献
104.
Andrea Facchini Adriana Rita Mariani Stefano Papa Erminia Mariani Francesco Antonio Manzoli 《Immunology letters》1984,8(4):207-210
Human T lymphocyte subsets, identified by means of OKT3, 4 and 8 monoclonal antibodies, were isolated by a fluorescence activated cell sorter (FACS IV) and analyzed for distribution of alpha-naphthyl acetate esterase (ANAE) activity. As compared to OKT8+ lymphocytes a higher proportion of OKT4+ lymphocytes was ANAE-positive exibiting a spot or dot-like pattern in the cytoplasm. OKT8 and 4 positive subsets showed a similar ANAE distribution in diffuse granular form. Although OKT4 and OKT8 populations presented a different ANAE dot-like reactivity, this marker did not allow as clear a distinction between them as that reported for TG and TM lymphocytes. 相似文献
105.
Andrea Fleig Peter C. Ruben Martin D. Rayner 《Pflügers Archiv : European journal of physiology》1994,427(5-6):399-405
Na currents recorded from inside-out macropatches excised from Xenopus oocytes expressing the subunit of the rat brain Na channel IIA show at least two distinguishable components in their inactivation time course, with time constants differing about tenfold (
h1 = approx. 150 s and
h2 = approx. 2 ms). In excised patches, the inactivation properties of Na currents changed with time, favoring the faster inactivation kinetics. Analysis of the fast and slow current kinetics shows that only the relative magnitudes of
h1 and
h2 components are altered without significant changes in the time constants of activation or inactivation. In addition, voltage dependence of both activation and steady-state inactivation of Na currents are shifted to more negative potentials in patches with predominantly fast inactivation, although reversal potentials and valences remained unaltered. We conclude that the two inactivation modes discerned in this study are conferred by two states of Na channel the interconversion of which are regulated by an as yet unknown mechanism that seems to involve cytosolic factors. 相似文献
106.
Maria L. Dentici Vittorio Maglione Emanuele Agolini Gino Catena Rossella Capolino Valentina Lanari Antonio Novelli Lorenzo Sinibaldi Davide Vecchio Michaela V. Gonfiantini Marina Macchiaiolo Maria C. Digilio Bruno Dallapiccola Andrea Bartuli 《American journal of medical genetics. Part A》2020,182(8):1977-1984
The tubulinopathies refer to a wide range of brain malformations caused by mutations in one of the seven genes encoding different tubulin's isotypes. The β‐tubulin isotype III (TUBB3) gene has a primary function in nervous system development and axon generation and maintenance, due to its neuron‐specific expression pattern. A recurrent heterozygous mutation, c.1228G > A; p.E410K, in TUBB3 gene is responsible of a rare disorder clinically characterized by congenital fibrosis of the extraocular muscle type 3 (CFEOM3), intellectual disability and a wide range of neurological and endocrine abnormalities. Other mutations have been described spanning the entire gene and genotype–phenotype correlations have been proposed. We report on a 3‐year‐old boy in whom clinical exome sequencing allowed to identify a de novo TUBB3 E410K mutation as the molecular cause underlying a complex phenotype characterized by a severe bilateral palpebral ptosis refractory to eye surgery, psychomotor delay, absent speech, hypogonadism, celiac disease, and cyclic vomiting. Brain MRI revealed thinning of the corpus callosum with no evidence of malformation cortical dysplasia. We reviewed available records of patients with TUBB3 E410K mutation and compared their phenotype with the clinical outcome of patients with other mutations in TUBB3 gene. The present study confirms that TUBB3 E410K results in a clinically recognizable phenotype, unassociated to the distinct cortical dysplasia caused by other mutations in the same gene. Early molecular characterization of TUBB3 E410K syndrome is critical for targeted genetic counseling and prompt prospective care in term of neurological, ophthalmological, endocrine, and gastrointestinal follow‐up. 相似文献
107.
Detection of methicillin-resistant Staphylococcus aureus and simultaneous confirmation by automated nucleic acid extraction and real-time PCR 下载免费PDF全文
Grisold AJ Leitner E Mühlbauer G Marth E Kessler HH 《Journal of clinical microbiology》2002,40(7):2392-2397
A molecular assay for the simultaneous detection of a Staphylococcus aureus-specific gene and the mecA gene, responsible for the resistance to methicillin in staphylococci, was evaluated. The assay included an automated DNA extraction protocol conducted with a MagNA Pure instrument and real-time PCR conducted with a LightCycler instrument. The performance and robustness of the assay were evaluated for a suspension of methicillin-resistant S. aureus (MRSA) strain with a turbidity equivalent to a McFarland standard of 0.5, which was found to be the ideal working concentration. The specificity of the new molecular assay was tested with a panel of 30 gram-negative and gram-positive bacterial strains other than MRSA. No cross-reactivity was observed. In a clinical study, 109 isolates of MRSA were investigated. All clinical MRSA isolates gave positive results for the S. aureus-specific genomic target, and all but one were positive for the mecA gene. In conclusion, the new molecular assay was found to be quick, robust, and laborsaving, and it proved to be suitable for a routine molecular diagnostic laboratory. 相似文献
108.
Vincenzo Di Stefano Raffaele Ornello Andrea Gagliardo Angelo Torrente Elisa Illuminato Valeria Caponnetto Ilaria Frattale Raffaella Golini Chiara Di Felice Fabiola Graziano Maria Caccamo Davide Ventimiglia Salvatore Iacono Gabriella Matarazzo Francesco Armetta Giuseppe Battaglia Alberto Firenze Simona Sacco Filippo Brighina 《Nutrients》2021,13(4)
Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life. 相似文献
109.
Jeffrey M. Lorch Steven J. Price Julia S. Lankton Andrea N. Drayer 《Emerging infectious diseases》2021,27(7):1986
Ophidiomycosis represents a conservation threat to wild snake populations. The disease was reported in North America early in the 21st century, but the history of ophidiomycosis has not been investigated. We examined museum specimens and confirmed cases of ophidiomycosis >50 years before the disease’s reported emergence. 相似文献
110.
Ashford Kristin McCubbin Andrea Barnett Janine Blair Lisa M. Lei Feitong Bush Heather Breland Alison 《Maternal and child health journal》2021,25(8):1175-1181
Maternal and Child Health Journal - In the US, approximately 8% of pregnant women smoke, and 5–11.9% currently use ENDS products. The health effects of ENDS use are debated; however, most... 相似文献