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101.
Katrin Friedrich Lin Lee Dru F. Leistritz Gudrun Nürnberg Bidisha Saha Fuki M. Hisama Daniel K. Eyman Davor Lessel Peter Nürnberg Chumei Li María J. Garcia-F-Villalta Carolien M. Kets Joerg Schmidtke Vítor Tedim Cruz Peter C. Van den Akker Joseph Boak Dincy Peter Goli Compoginis Kivanc Cefle Sukru Ozturk Norberto López Theda Wessel Martin Poot P. F. Ippel Birgit Groff-Kellermann Holger Hoehn George M. Martin Christian Kubisch Junko Oshima 《Human genetics》2010,128(1):103-111
Werner syndrome (WS) is an autosomal recessive segmental progeroid syndrome caused by null mutations at the WRN locus, which codes for a member of the RecQ family of DNA helicases. Since 1988, the International Registry of Werner syndrome had enrolled 130 molecularly confirmed WS cases from among 110 worldwide pedigrees. We now report 18 new mutations, including two genomic rearrangements, a deep intronic mutation resulting in a novel exon, a splice consensus mutation leading to utilization of the nearby splice site, and two rare missense mutations. We also review evidence for founder mutations among various ethnic/geographic groups. Founder WRN mutations had been previously reported in Japan and Northern Sardinia. Our Registry now suggests characteristic mutations originated in Morocco, Turkey, The Netherlands and elsewhere. 相似文献
102.
O Fedorova Yu V Fedorov E Gulakova N Schepel M Alfimov U Goli J Saltiel 《Photochemical & photobiological sciences》2007,6(10):1097-1105
2-styrylbenzothiazole (1) and cinnamic acid (2) derivatives containing 15-crown-5 ether moieties form a supramolecular assembly in the presence of Ba(2+) cations in acetonitrile. The assembly is stabilized by hydrogen bonding between the heterocyclic N atom of 1 and the proton of the carboxylic group of 2, by sandwich Ba(2+) complex formation between the crown ether moieties of 1 and 2, and by pi-pi stacking interactions. Irradiation of solutions containing these supramolecular complexes leads to highly specific formation of an unsymmetrical cycloadduct. This investigation provides an interesting example of supramolecular control of [2 + 2]-photocyclization in solution. 相似文献
103.
Background/Objective
Children and women comprise vulnerable populations in terms of health and are gravely affected by the impact of economic inequalities through multi-dimensional channels. Urban areas are believed to have better socioeconomic and maternal and child health indicators than rural areas. This perception leads to the implementation of health policies ignorant of intra-urban health inequalities. Therefore, the objective of this study is to explain the pathways of economic inequalities in maternal and child health indicators among the urban population of India.Methods
Using data from the third wave of the National Family Health Survey (NFHS, 2005–06), this study calculated relative contribution of socioeconomic factors to inequalities in key maternal and child health indicators such as antenatal check-ups (ANCs), institutional deliveries, proportion of children with complete immunization, proportion of underweight children, and Infant Mortality Rate (IMR). Along with regular CI estimates, this study applied widely used regression-based Inequality Decomposition model proposed by Wagstaff and colleagues.Results
The CI estimates show considerable economic inequalities in women with less than 3 ANCs (CI = −0.3501), institutional delivery (CI = −0.3214), children without fully immunization (CI = −0.18340), underweight children (CI = −0.19420), and infant deaths (CI = −0.15596). Results of the decomposition model reveal that illiteracy among women and her partner, poor economic status, and mass media exposure are the critical factors contributing to economic inequalities in maternal and child health indicators. The residuals in all the decomposition models are very less; this implies that the above mentioned factors explained maximum inequalities in maternal and child health of urban population in India.Conclusion
Findings suggest that illiteracy among women and her partner, poor economic status, and mass media exposure are the critical pathways through which economic factors operate on inequalities in maternal and child health outcomes in urban India. 相似文献104.
Keivan Majidzadeh-A Ahmad Kaviani Rezvan Esmaeili Leila Farahmand Mohammad Hossein Shojamoradi Ali Akbar Zare Leila Eini Fereshteh Abbasvandi Asieh Olfatbakhsh Hadi Moazen 《Cell and tissue banking》2013,14(1):11-20
The information gained from the Human Genome Project has facilitated molecular as well as cellular studies not only to find the origins of Breast Cancer (BC), but also to create novel, and effective treatments. In order to provide an infrastructure for local and international research in this area, Iranian Center for Breast Cancer (ICBC) has established a Bio-Bank (BB) for BC. This article describes the aim, structure, and activities in general, and the challenging issues confronting the bank as a model for the establishment of Bio-Banks in developing countries in particular. The methods employed by the Bank could be explained in the following categories:
- Blood and Tissue sampling,
- Preparation and Banking of collected Samples,
- Clinical and Histopathology data collection,
- Collaboration Protocol,
- Challenging issues, and the programs to confront the problems.
105.
Cannabinoid system plays an important role in controlling neuronal excitability and brain function. On the other hand, modulation
of gamma-aminobutyric acid (GABA) transmission is one of the initial strategies for the treatment of seizure. The aim of the
present study was to evaluate possible interaction between cannabinoidergic and GABAergic systems in pentylenetetrazole (PTZ)-induced
acute seizure in rat. Drugs were administered by intracerebroventricular (i.c.v.) administration 20 min before a single intraperitoneal
(i.p.) injection of PTZ and the latency to the first generalized tonic-clonic seizure was measured. Both the cannabinoid receptor
agonist WIN55212-2 (10, 30, 50 and 100 μg/rat) and the GABA-A receptor agonist isoguvacine (IGN; 10, 30 and 50 μg/rat) significantly
increased the latency of seizure occurrence. Moreover, the fatty acid amide hydrolase inhibitor URB597 showed no anticonvulsive
effect while the monoacyl glycerol lipase (MAGL) inhibitor URB602 (10, 50 and 100 μg/rat) protected rats against PTZ-induced
seizure. Moreover, co-administration of IGN and cannabinoid compounds attenuated the anticonvulsant action of both WIN55212-2
and IGN in this model of seizure. Our data suggests that exogenous cannabinoid WIN55212-2 and MAGL inhibitor URB602 imply
their antiseizure action in part through common brain receptorial system. Moreover, the antagonistic interaction of cannabinoids
and IGN in protection against PTZ-induced seizure could suggest the involvement of GABAergic system in their anticonvulsant
action. 相似文献
106.
Shrubs of niger seed with phyllody and internode elongation symptoms suggestive of phytoplasma infections occurred in the central regions of Iran. Phytoplasma was detected by polymerase chain reaction (PCR) and nested PCR amplifications using phytoplasma universal primer pairs P1/P7 and R16F2n/R16R2. Using aster yellows group–specific primer pair rp(I)F1A/rp(I)R1A, a fragment of 1212 bp of the rp genes was amplified from DNA samples of infected plants. Random fragment length polymorphism (RFLP) analyses of R16F2n/R16R2‐amplified products using the CfoI restriction enzyme confirmed that Iranian niger seed phyllody phytoplasma is associated with aster yellows group phytoplasmas. Sequence analyses of the partial rp genes fragment indicated that the Iranian niger seed phyllody phytoplasma, which was collected from central regions of Iran, is related to ‘Candidatus Phytoplasma asteris’. This is the first report of a phytoplasma infecting the niger seed plant. 相似文献
107.
Background
Penicillin resistance in Streptococcus pneumoniae is mediated by a mosaic of genes encoding altered penicillin-binding proteins (PBPs). Nonetheless, S. pneumoniae has also developed non-PBP mechanisms implicated in penicillin resistance. In this study, whole genome sequencing of resistant organisms was used to discover mutations implicated in resistance to penicillin.Results
We sequenced two S. pneumoniae isolates selected for resistance to penicillin in vitro. The analysis of the genome assemblies revealed that six genes were mutated in both mutants. These included three pbp genes, and three non-pbp genes, including a putative iron permease, spr1178. The nonsense mutation in spr1178 always occurred in the first step of the selection process. Although the mutants had increased resistance to penicillin, the introduction of altered versions of PBPs into a penicillin-susceptible strain by sequential transformation led to strains with a minimal increase in resistance, thus implicating other genes in resistance. The introduction by transformation of the non-PBP recurrent mutations did not increase penicillin resistance, but the introduction of the nonsense mutation in the putative iron permease spr1178 led to a reduced accumulation of reactive oxygen species following exposure to penicillin and to other bactericidal antibiotics as well.Conclusions
This study indicates that the selection of resistance to penicillin in S. pneumoniae involves the acquisition of mutations conferring tolerance to the antibiotic-induced accumulation of oxidants, which translates into an increased survival that putatively enables the selection of major resistance determinants such as mutations in PBPs. 相似文献108.
Adhesion to collagen is an important virulence determinant for the periodontal pathogen Aggregatibacter actinomycetemcomitans. Binding to collagen is mediated by the extracellular-matrix protein adhesin-A (EmaA). EmaA is a homotrimeric autotransporter protein that forms flexible antenna-like appendages on the bacterium surface. An ellipsoidal structure at the distal end of the appendage, composed of three subdomains, contains the functional domain of the molecule. A correlation between amino-acid sequence and subdomain structure (SI and SII) was proposed based on an analysis of the volume/molecular weight ratio. EmaA from three mutant strains (deletions of amino-acids 70-206 and 70-386 and a substitution mutation G162S) has been studied by electron microscopy to test this hypothesis. 3D structures were analyzed using single-axis tilt tomography of negatively stained preparations of bacteria combined with subvolume averaging. Additionally, a large number of 2D images of the apical domain of the adhesins from the mutants were extracted from micrographs of the bacterial surface, aligned and classified. The combined data showed that amino-acids 70-206 localize to subdomain SI and 70-386 comprise subdomains SI and SII. Moreover, we showed that the substitution mutation G162S, which abolishes collagen binding activity, does not affect the overall structural integrity of the functional domain. However, the structure of subdomain SI in this mutant is slightly altered with respect to the wild-type strain. These data also have allowed us to interpret the architectural features of each subdomain of EmaA in more detail and to correlate the 3D structure of the functional domain of EmaA with the amino-acid sequence. 相似文献
109.
Marko Goličnik 《Engineering in Life Science》2012,12(1):104-108
A recent article of Zavrel et al. in this journal (Eng. Life Sci. 2010, 10, 191–200) described a comparison of several computer programs for progress‐curve analysis with respect to different computational approaches for parameter estimation. The authors applied both algebraic and dynamic parameter estimations, although they omitted time‐course analysis through the integrated rate equation. Recently, it was demonstrated that progress‐curve analysis through the integrated rate equation can be considered a simple and useful alternative for enzymes that obey the generalized Michaelis–Menten reaction mechanism. To complete this gap, the time‐dependent solution of the generalized Michaelis–Menten equation is here fitted to the progress curves from the Zavrel et al. reference article. This alternative rate‐integration approach for determining the kinetics parameters of Michaelis–Menten‐type enzymes yields the values with the greatest accuracy, as compared with the results obtained by other (algebraic or dynamic) parameter estimations. 相似文献
110.
Mirzaii M Emaneini M Maleknejad P Jonaidi N Fooladi AA Aligholi M Jabalameli F Halimi S Taherikalani M Kasaeian A 《Acta microbiologica et immunologica Hungarica》2012,59(1):1-11
There are documents that confirm the cycle of bacterial transmission between patients, staff, and the inanimate environment. The environment may have more effect on intensive care units (ICUs), because the patients who require intensive care have unstable clinical conditions and are more sensitive to infections. The aim of this study was to determine the prevalence of bacteria in air and inanimate surface in the ICUs and to compare the microbial levels to standard levels.Air and inanimate surface in the four ICUs of a teaching hospital underwent weekly surveillance by means of air sampler and swabs for a period of six-month. Total bacterial counts were evaluated onto trypticase soy agar and mannitol salt agar (MSA).A total of 725 samples [air (168) and inanimate surfaces (557)] were collected. The total mean ± SD CFU/m3 of airborne bacteria in all of the ICUs were 115.93 ± 48.04. The most common bacteria in air of the ICUs were Gram-positive cocci (84.2%). The total mean ± SD airborne of Staphylococcus aureus was 12.10±8.11 CFU/m3. The highest levels of S. aureus contamination were found in ventilators and bed ledges. More suitable disinfection of hospital environments and monthly rotation in utilization of the various disinfectant agents are needed for the prevention of airborne and inanimate transmission of S. aureus. 相似文献