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141.
The etiology of cleft lip (CL) and/or cleft palate (CP) has been extensively studied in industrialized countries and is suggested to be heterogeneous with increasing evidence that both genetic and environmental factors are operating. To evaluate this assertion in a developing country like Pakistan, a case finding cross-sectional study was completed from 1st July 2010 to 31st May 2011 for 100 cases of CL and/or CP referred to the Genetic Clinic of the Children’s Hospital, Lahore, Pakistan. A clinical examination followed by necessary diagnostic work-up was completed for each case. The cause of CL and/or CP was clear in 18% of the children (n = 18). Environmental causes were found in 6 children (four mothers developed hyperthermia during the 2nd month of gestation, one mother was diabetic, and one mother was a known case of epilepsy and took sodium valproate throughout her pregnancy). Six children were suffering from known genetic malformation syndromes (each with Jarcho-Levin syndrome, Oral-Facial-Digital syndrome type XI, Oral-Duplication syndrome, Kabuki syndrome, Fronto-nasal dysplasia and Nager syndrome). Novel chromosomal aberrations were identified in 2 children. In 82% of the children (n = 82) the cause of oro-facial clefts remained unknown. Impact of gender and consanguinity on the development of CL and/or CP was also studied. Prevalence of CP was significantly more among female children as compared to that in males (P < 0.05). Associated anomalies were present in 18% of the cases, anomalies of the craniofacial region being the most common. These findings were compared with regional and international studies.  相似文献   
142.
Biological Trace Element Research - The original version of this article unfortunately contained a mistake.  相似文献   
143.
Autophagy is one of the basic cellular mechanism during preimplantation development of mammalian embryos, and it plays crucial role in several physiological processes. It is induced by interleukin (IL)-1β in mammalian cells. Our present study shows that IL-1β is important for autophagy activation in embryo development. Our in vitro culture system analysis shows effect of IL-1β in medium on the development of mouse embryos and it was found to be concentration dependent. A preimplantation embryo culture using medium containing IL-1β did not improve cleavage and blastocyst development rates of mouse embryos; however, blastocyst quality was significantly improved by increasing total cell number, especially in supplementary 20 ng/mL IL-1β. Furthermore, autophagy activation mainly occurs in 2 to 4 cell embryo and blastocyst, 20 ng/mL IL-1β into culture medium can effectively enhance levels of messenger RNA and protein of autophagy-related-factors in 2 to 4 cell embryos and blastocyst, while these factors reduce in VGX-1027 (IL-1β inhibitor) groups that also reduce the quality of blastocyst. Effects of IL-1β on the development of embryo reduced in 20 ng/mL IL-1β supplemented group when 5 mM 3-methyladenine (3-MA) was also added, which used to inhibit autophagy activation in endogenous PtdIns3Ks signal pathway. Our current results show that exogenous IL-1β can effectively induce autophagy in mouse embryos at stages of 2 to 8 cell and blastocyst, that also help to improve the quality of blastocyst.  相似文献   
144.
A number of studies have established that plant growth and development in oilseed rape (Brassica napus L.) are hampered by salinity stress. Nowadays, researchers have focused on the use of plant growth regulators to increase plant tolerance against salinity. An experiment was performed to evaluate the effects of 5-aminolevulinic acid (ALA, 30 mg l?1) on Brassica napus L. (cv. ??ZS 758??) plants under NaCl (100, 200 mM) salinity. Data presented here were recorded on two different leaf positions (first and third) to have a better understanding of the ameliorative role of ALA on NaCl-stressed oilseed rape plants. Results have shown that increasing salinity imposed negative impact on relative growth rate (root and shoot) and leaf water relations (osmotic potential and relative water content), whereas enhanced the level of relative conductivity, malondialdehyde (MDA) content, osmolytes (soluble sugar, soluble protein, free amino acid and proline) concentration, reactive oxygen species (ROS), and enzymatic (ascorbate peroxidase, guaiacol peroxidase, catalase and superoxide dismutase) and non-enzymatic (reduced glutathione and ascorbate) antioxidants activity in two different leaf position samples. Foliar application of ALA improved relative growth rate (root and shoot) and leaf water relations (osmotic potential and relative water content), and also triggered the further accumulation of osmolytes (soluble sugar, soluble protein, free amino acid and proline) as well as enzymatic (ascorbate peroxidase, guaiacol peroxidase, catalase and superoxide dismutase) and non-enzymatic (reduced glutathione and ascorbate) antioxidants activity in both leaf samples, whereas decreased the membrane permeability, MDA content and ROS production. Our results also indicate that osmolytes are preferentially accumulated in younger tissues.  相似文献   
145.
Combining the advantages of signal-on strategy and nicking endonuclease assisted electrochemistry signal amplification (NEAESA), a new sensitive and signal-on electrochemical DNA biosensor for the sequence specific DNA detection based on NEAESA has been developed for the first time. A Hairpin-shape probe (HP), containing the target DNA recognition sequence, is thiol-modified at 5' end and immobilized on gold electrode via Au-S bonding. Subsequently, the HP modified electrode is hybridized with target DNA to form a duplex. Then the nicking endonuclease is added and nicks the HP strand in the duplex. After nicking, 3'-ferrocene (Fc)-labeled part complementary probe (Fc-PCP) is introduced on the electrode surface by hybridizing with the thiol-modified HP fragment, which results in the generation of electrochemical signal. Hence, the DNA biosensor is constructed successfully. The present DNA biosensor shows a wide linear range of 5.0×10(-13)-5.0×10(-8)M for detecting target DNA, with a low detection limit of 0.167pM. The proposed strategy does not require any amplifying labels (enzymes, DNAzymes, nanoparticles, etc.) for biorecognition events, which avoids false-positive results to occur frequently. Moreover, the strategy has the benefits of simple preparation, convenient operation, good selectivity, and high sensitivity. With the advantages mentioned above, this simple and sensitive strategy has the potential to be integrated in portable, low cost and simplified devices for diagnostic applications.  相似文献   
146.
T cell costimulation is important for T cell activation. The CD27/CD70 pathway contributes to effector and memory T cell development and is involved in T cell and B cell activation. CD27/CD70 is known for having opposing roles during different models of antigenic challenges. During primary T cell responses to influenza virus infection or during tumor challenges, CD27/CD70 costimulation has a positive role on T cell responses. However, during some chronic infections, constitutive triggering of this signaling pathway has a negative role on T cell responses. It is currently unclear what specific characteristic of an antigen determines the outcome of CD27/CD70 costimulation. We investigated the effect of a transient CD70 blockade during an acute or a chronic lymphocytic choriomeningitis virus (LCMV) infection in mice. Blockade of this pathway during acute LCMV infection (Armstrong strain) resulted in delayed T cell responses and decreased CD127 (interleukin-7 receptor α [IL-7Rα] chain) conversion. Upregulation of CD127 is an important event in T cell differentiation that heralds the passage of an effector T cell to a long-lived memory T cell. In contrast to the reduced CD8 T cell responses after CD70 blockade during acute infection, CD70 blockade during chronic LCMV infection resulted in increased CD8 T cell responses. Our data show the dual roles of this costimulatory pathway in acute versus persistent antigen challenge. Our findings suggest that antigen persistence may determine the effect of CD27/CD70 signaling on CD8 T cell responses. Tailored triggering or blockade of this costimulatory pathway may be important in vaccination regimens against acute or chronic pathogens.  相似文献   
147.
An efficient protocol of shoot organogenesis and plant regeneration from internode derived callus has been developed for Capsicum annuum. Optimal callus was developed from internodal segments on Murashige and Skoog (MS) medium supplemented with 10 μM 2,4-dichlorophenoxy acetic acid (2,4-D) and 2.0 μM 6-benzyladenine (BA). Shoot differentiation was achieved from the surface of callus when transferred on shoot induction medium containing BA and thidiazuron (TDZ) alone or in combination. The highest number of de novo adventitious shoots (25.4?±?1.42) and shoot length (4.6?±?0.37 cm) was recorded on MS medium supplemented with 5.0 μM BA and 2.5 μM TDZ. The individual elongated shoots were rooted well on MS medium supplemented with 1.0 μM Indole-3-butyric acid (IBA). The in vitro raised plantlets with properly developed shoot and roots were acclimatized successfully and grew well in the greenhouse. All the regenerated plants appeared normal with respect to morphology and growth characteristics with 85% survival rate.  相似文献   
148.
We ascertained three consanguineous Pakistani families (PKDF291, PKDF335 and PKDF793) segregating nonsyndromic recessive hearing loss. The hearing loss segregating in PKDF335 and PKDF793 is moderate to severe, whereas it is profound in PKDF291. The maximum two-point LOD scores are 3.01 (D19S1034), 3.85 (D19S894) and 3.71 (D19S894) for PKDF291, PKDF335 and PKDF793, respectively. Haplotype analyses of the three families define a 1.16 Mb region of overlap of the homozygous linkage intervals bounded by markers D19S216 (20.01 cM) and D19S1034 (20.75 cM). These results define a novel locus, DFNB72, on chromosome 19p13.3. There are at least 22 genes in the 1.16 Mb interval, including PTPRS, ZNRF4 and CAPS. We identified no pathogenic variants in the exons and flanking intronic sequences of these three genes in affected members of the DFNB72 families. DFNB72 is telomeric to DFNB68, the only other known deafness locus with statistically significant support for linkage to chromosome 19p.  相似文献   
149.
Journal of Plant Growth Regulation - Many agricultural soils fail to supply sufficient boron (B) and phosphorus (P) to growing plants due to their adsorption, precipitation and fixation phenomena....  相似文献   
150.
Ahmad  Rasheed  Alsmadi  Izzat  Alhamdani  Wasim  Tawalbeh  Lo&#;ai 《Cluster computing》2022,25(3):2125-2141
Cluster Computing - Data analytics projects span all types of domains and applications. Researchers publish results using certain datasets and classification models. They present results with a...  相似文献   
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