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221.
Data on 550 healthy pregnant women, 550 healthy fathers and their healthy term neonates born from singleton pregnancies (37(+0) through 41(+6) week) during a one-year period were reviewed. Maternal mean age was 27.7 +/- 9.37 years, mean pregestational weight 64.0 +/- 9.50 kg, mean gestational weight gain 15.4 +/- 4.33 kg, mean height 169.7 +/- 5.81 cm, and mean gestational age 40.1 +/- 0.95 weeks. Paternal mean age was 31.4 +/- 6.22 years, mean weight 84.6 +/- 10.35 kg, and mean height 182.8 +/- 6.84 cm. Mean birth weight was 3,709.8 +/- 500.48 g and 3,562.5 +/- 443.02 g, and mean birth length 51.5 +/- 1.91 cm and 50.7 +/- 1.62 cm in male and female newborns, respectively, yielding a birth weight greater by 147.3 g and birth length by 0.8 cm in the former. Study variables showed statistically significant correlations: maternal age contributed to the significant correlation between maternal weight and parity, maternal pregestational weight, weight at delivery, gestational weight gain and body height correlated significantly with neonatal birth weight and birth length, gestational age correlated significantly with neonatal weight and length (p = 0.01 all), parity had no major impact (p > 0.05). Paternal height and weight correlated significantly with neonatal birth weight and birth length (p = 0.01). Study results pointed to a significant correlation of maternal pregestational weight, gestational weight gain and body height, and of paternal weight and height with the neonate birth weight and birth length. 相似文献
222.
Zoltán Dezső Yuri Nikolsky Evgeny Sviridov Weiwei Shi Tatiana Serebriyskaya Damir Dosymbekov Andrej Bugrim Eugene Rakhmatulin Richard J Brennan Alexey Guryanov Kelly Li Julie Blake Raymond R Samaha Tatiana Nikolskaya 《BMC biology》2008,6(1):1-15
Background
Periodic patterning of iterative structures is a fundamental process during embryonic organization and development. Studies have shown how gene networks are employed to pattern butterfly eyespots, fly bristles and vertebrate epithelial appendages such as teeth, feathers, hair and mammary glands. Despite knowledge of how these features are organized, little is known about how diversity in periodic patterning is generated in nature. We address this problem through the molecular analysis of oral jaw dental diversity in Lake Malawi cichlids, where closely related species exhibit from 1 to 20 rows of teeth, with total teeth counts ranging from around 10 to 700.Results
We investigate the expression of conserved gene networks (involving bmp2, bmp4, eda, edar, fgf8, pax9, pitx2, runx2, shh and wnt7b) known to pattern iterative structures and teeth in other vertebrates. We show that spatiotemporal variation in expression pattern reflects adult morphological diversity among three closely related Malawi cichlid species. Combinatorial epithelial expression of pitx2 and shh appears to govern the competence both of initial tooth sites and future tooth rows. Epithelial wnt7b and mesenchymal eda are expressed in the inter-germ and inter-row regions, and likely regulate the spacing of these shh-positive units. Finally, we used chemical knockdown to demonstrate the fundamental role of hedgehog signalling and initial placode formation in the organization of the periodically patterned cichlid dental programme.Conclusion
Coordinated patterns of gene expression differ among Malawi species and prefigure the future-ordered distribution of functional teeth of specific size and spacing. This variation in gene expression among species occurs early in the developmental programme for dental patterning. These data show how a complex multi-rowed vertebrate dentition is organized and how developmental tinkering of conserved gene networks during iterative pattern formation can impact upon the evolution of trophic novelty. 相似文献223.
Background
The chlamydiae alter many aspects of host cell biology, including the division process, but the molecular biology of these alterations remains poorly characterized. Chlamydial inclusion membrane proteins (Incs) are likely candidates for direct interactions with host cell cytosolic proteins, as they are secreted to the inclusion membrane and exposed to the cytosol. The inc gene CT223 is one of a sequential set of orfs that encode or are predicted to encode Inc proteins. CT223p is localized to the inclusion membrane in all tested C. trachomatis serovars. 相似文献224.
Christoph U. Correll Samuele Cortese Giovanni Croatto Francesco Monaco Damir Krinitski Gonzalo Arrondo Edoardo
G. Ostinelli Caroline Zangani Michele Fornaro Andrs Estrad Paolo FusarPoli Andre F. Carvalho Marco Solmi 《World psychiatry》2021,20(2):244
Top‐tier evidence on the safety/tolerability of 80 medications in children/adolescents with mental disorders has recently been reviewed in this journal. To guide clinical practice, such data must be combined with evidence on efficacy and acceptability. Besides medications, psychosocial interventions and brain stimulation techniques are treatment options for children/adolescents with mental disorders. For this umbrella review, we systematically searched network meta‐analyses (NMAs) and meta‐analyses (MAs) of randomized controlled trials (RCTs) evaluating 48 medications, 20 psychosocial interventions, and four brain stimulation techniques in children/adolescents with 52 different mental disorders or groups of mental disorders, reporting on 20 different efficacy/acceptability outcomes. Co‐primary outcomes were disease‐specific symptom reduction and all‐cause discontinuation (“acceptability”). We included 14 NMAs and 90 MAs, reporting on 15 mental disorders or groups of mental disorders. Overall, 21 medications outperformed placebo regarding the co‐primary outcomes, and three psychosocial interventions did so (while seven outperformed waiting list/no treatment). Based on the meta‐analytic evidence, the most convincing efficacy profile emerged for amphetamines, methylphenidate and, to a smaller extent, behavioral therapy in attention‐deficit/hyperactivity disorder; aripiprazole, risperidone and several psychosocial interventions in autism; risperidone and behavioral interventions in disruptive behavior disorders; several antipsychotics in schizophrenia spectrum disorders; fluoxetine, the combination of fluoxetine and cognitive behavioral therapy (CBT), and interpersonal therapy in depression; aripiprazole in mania; fluoxetine and group CBT in anxiety disorders; fluoxetine/selective serotonin reuptake inhibitors, CBT, and behavioral therapy with exposure and response prevention in obsessive‐compulsive disorder; CBT in post‐traumatic stress disorder; imipramine and alarm behavioral intervention in enuresis; behavioral therapy in encopresis; and family therapy in anorexia nervosa. Results from this umbrella review of interventions for mental disorders in children/adolescents provide evidence‐based information for clinical decision making. 相似文献
225.
Nicola Marchi Jeffrey J. Bazarian Vikram Puvenna Mattia Janigro Chaitali Ghosh Jianhui Zhong Tong Zhu Eric Blackman Desiree Stewart Jasmina Ellis Robert Butler Damir Janigro 《PloS one》2013,8(3)
The acknowledgement of risks for traumatic brain injury in American football players has prompted studies for sideline concussion diagnosis and testing for neurological deficits. While concussions are recognized etiological factors for a spectrum of neurological sequelae, the consequences of sub-concussive events are unclear. We tested the hypothesis that blood-brain barrier disruption (BBBD) and the accompanying surge of the astrocytic protein S100B in blood may cause an immune response associated with production of auto-antibodies. We also wished to determine whether these events result in disrupted white matter on diffusion tensor imaging (DT) scans. Players from three college football teams were enrolled (total of 67 volunteers). None of the players experienced a concussion. Blood samples were collected before and after games (n = 57); the number of head hits in all players was monitored by movie review and post-game interviews. S100B serum levels and auto-antibodies against S100B were measured and correlated by direct and reverse immunoassays (n = 15 players; 5 games). A subset of players underwent DTI scans pre- and post-season and after a 6-month interval (n = 10). Cognitive and functional assessments were also performed. After a game, transient BBB damage measured by serum S100B was detected only in players experiencing the greatest number of sub-concussive head hits. Elevated levels of auto-antibodies against S100B were elevated only after repeated sub-concussive events characterized by BBBD. Serum levels of S100B auto-antibodies also predicted persistence of MRI-DTI abnormalities which in turn correlated with cognitive changes. Even in the absence of concussion, football players may experience repeated BBBD and serum surges of the potential auto-antigen S100B. The correlation of serum S100B, auto-antibodies and DTI changes support a link between repeated BBBD and future risk for cognitive changes. 相似文献
226.
Significant enhancement of fluorescence on hybridization of a molecular beacon to a target DNA in the presence of a site-specific DNA nickase 总被引:1,自引:0,他引:1
Zheleznaya LA Kopein DS Rogulin EA Gubanov SI Matvienko NI 《Analytical biochemistry》2006,348(1):123-126
We have developed a simple isothermal (55 degrees C) reaction that permits detection of DNA targets using only two components: a molecular beacon and a site-specific DNA nickase without deoxyribonucleotide triphosphates and primers. The loop sequence of the molecular beacon should contain a DNA nickase recognition site. The nickase-molecular beacon (NMB) combination permits a 100-fold increase in fluorescent signal. The applications of the NMB assay for enhancement of fluorescent signal in some isothermal methods are discussed. 相似文献
227.
Four hapalindole-related alkaloids, namely fischambiguines A and B, ambiguine P, ambiguine Q nitrile as well as ambiguine G nitrile were identified from the cultured cyanobacterium Fischerella ambigua (UTEX 1903). The structures were determined by spectroscopic analysis including MS, 1D and 2D NMR and X-ray crystallography. The alkaloids possessed fused pentacyclic and hexacyclic carbon skeletons. Fischambiguine B displayed a strong inhibitory activity against Mycobacterium tuberculosis with an MIC value of 2 μM, with no detectable cytotoxicity in a Vero cell line. 相似文献
228.
Phytoplankton population density and volume as indicators of eutrophication in the eastern part of the Adriatic Sea 总被引:3,自引:1,他引:2
Damir Viličić 《Hydrobiologia》1989,174(2):117-132
Population density and volume-biomass of microplankton, nanoplankton and total phytoplankton were analyzed at 14 stations
along the eastern part of the Adriatic Sea. Based upon data frequency distribution, four categories of ecosystems were established
in the investigated area. Criteria for ecosystem categorization and biological evaluation of eutrophication are proposed. 相似文献
229.
Reaction of the potassium salt of the N-thiophosphorylthiourea H2NC(S)NHP(S)(OiPr)2 (HL) with Co(II), Ni(II), Zn(II) and Cd(II) cations in aqueous EtOH leads to the chelate complexes [ML2] all showing a 1,5-S,S′-coordination formed by the CS and PS sulfur atoms of two deprotonated ligands L−. The structures of the resulting compounds were studied by IR, UV-Vis, 1H, 31P{1H} NMR spectroscopy and microanalysis. The metal center is found in a tetrahedral environment in [CoL2], [ZnL2] and [CdL2]. According to NMR and UV-Vis spectroscopy the metal cation of [NiL2] exhibits square planar coordination geometry in CH2Cl2, CHCl3 and C6H6, while tetrahedral geometry is observed in acetone, DMSO and DMF. Regardless of the solvent used for the crystallization of [NiL2], the molecular structure in the solid is always square planar as was confirmed by XRD of single crystals and magnetic measurements of the polycrystalline material. The magnetic and photoluminescent properties of all complexes are also reported. 相似文献
230.
Andreas Blennow Katsiaryna Skryhan Vanja Tanackovic Susanne L. Krunic Shahnoor S. Shaik Mette S. Andersen Hanne‐Grethe Kirk Kre L. Nielsen 《Plant biotechnology journal》2020,18(10):2096-2108
Solanum tuberosum potato lines with high amylose content were generated by crossing with the wild potato species Solanum sandemanii followed by repeated backcrossing to Solanum tuberosum lines. The trait, termed increased amylose (IAm), was recessive and present after three generations of backcrossing into S. tuberosum lines (6.25% S. sandemanii genes). The tubers of these lines were small, elongated and irregular with small and misshaped starch granules and high sugar content. Additional backcrossing resulted in less irregular tuber morphology, increased starch content (4.3%–9.5%) and increased amylose content (29%–37.9%) but indifferent sugar content. The amylose in the IAm starch granules was mainly located in peripheral spots, and large cavities were found in the granules. Starch pasting was suppressed, and the digestion‐resistant starch (RS) content was increased. Comprehensive microarray polymer profiling (CoMPP) analysis revealed specific alterations of major pectic and glycoprotein cell wall components. This complex phenotype led us to search for candidate IAm genes exploiting its recessive trait. Hence, we sequenced genomic DNA of a pool of IAm lines, identified SNPs genome wide against the draft genome sequence of potato and searched for regions of decreased heterozygosity. Three regions, located on chromosomes 3, 7 and 10, respectively, displayed markedly less heterozygosity than average. The only credible starch metabolism‐related gene found in these regions encoded the isoamylase‐type debranching enzyme Stisa1. Decreased expression of mRNA (>500 fold) and reduced enzyme activity (virtually absent from IAm lines) supported Stisa1 as a candidate gene for IAm. 相似文献