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Find video protocols related to scientific articles indexed in Pubmed.
Hydroxychloroquine-Inhibited Dengue Virus Is Associated with Host Defense Machinery.
J. Interferon Cytokine Res.
PUBLISHED: 10-17-2014
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Hydroxychloroquine (HCQ) is an antimalarial drug also used in treating autoimmune diseases. Its antiviral activity was demonstrated in restricting HIV infection in vitro; however, the clinical implications remain controversial. Infection with dengue virus (DENV) is a global public health problem, and we lack an antiviral drug for DENV. Here, we evaluated the anti-DENV potential of treatment with HCQ. Immunofluorescence assays demonstrated that HCQ could inhibit DENV serotype 1-4 infection in vitro. RT-qPCR analysis of HCQ-treated cells showed induced expression of interferon (IFN)-related antiviral proteins and certain inflammatory cytokines. Mechanistic study suggested that HCQ activated the innate immune signaling pathways of IFN-?, AP-1, and NF?B. Knocking down mitochondrial antiviral signaling protein (MAVS), inhibiting TANK binding kinase 1 (TBK1)/inhibitor-?B kinase ? (IKK?), and blocking type I IFN receptor reduced the efficiency of HCQ against DENV-2 infection. Furthermore, HCQ significantly induced cellular production of reactive oxygen species (ROS), which was involved in the host defense system. Suppression of ROS production attenuated the innate immune activation and anti-DENV-2 effect of HCQ. In summary, HCQ triggers the host defense machinery by inducing ROS- and MAVS-mediated innate immune activation against DENV infection and may be a candidate drug for DENV infection.
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Genomic organization, transcriptomic analysis, and functional characterization of avian ?- and ?-keratins in diverse feather forms.
Genome Biol Evol
PUBLISHED: 08-24-2014
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Feathers are hallmark avian integument appendages, although they were also present on theropods. They are composed of flexible corneous materials made of ?- and ?-keratins, but their genomic organization and their functional roles in feathers have not been well studied. First, we made an exhaustive search of ?- and ?-keratin genes in the new chicken genome assembly (Galgal4). Then, using transcriptomic analysis, we studied ?- and ?-keratin gene expression patterns in five types of feather epidermis. The expression patterns of ?-keratin genes were different in different feather types, whereas those of ?-keratin genes were less variable. In addition, we obtained extensive ?- and ?-keratin mRNA in situ hybridization data, showing that ?-keratins and ?-keratins are preferentially expressed in different parts of the feather components. Together, our data suggest that feather morphological and structural diversity can largely be attributed to differential combinations of ?- and ?-keratin genes in different intrafeather regions and/or feather types from different body parts. The expression profiles provide new insights into the evolutionary origin and diversification of feathers. Finally, functional analysis using mutant chicken keratin forms based on those found in the human ?-keratin mutation database led to abnormal phenotypes. This demonstrates that the chicken can be a convenient model for studying the molecular biology of human keratin-based diseases.
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Triple infection keratitis.
Eye Contact Lens
PUBLISHED: 04-01-2014
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To analyze the demographics, risk factors, and clinical and microbiological characteristics of triple infection keratitis.
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Pediatric Thyroid Eye Disease-The Singapore Experience.
Orbit
PUBLISHED: 11-08-2013
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Abstract Purpose: To identify the demographics, risk factors, clinical manifestations and treatment methods of pediatric thyroid eye disease (TED) in a South-East Asian tertiary referral practice. Methods: Retrospective case series of all pediatric patients (aged 18 years and under) who presented to our TED clinic between Jan 2006 and Dec 2012. Results: Thirteen patients (26 eyes) were identified - 8 females (61.5%) and 5 males (38.5%), accounting for 6.2% of all TED patients in our practice. Median age was 10.0 years (range, 0.3-18.0). Positive family history was noted in 9 patients (69.2%) and there were no active/passive smokers. Mean follow-up duration was 1.81 years (range, 0-5.2). Common presenting signs included proptosis (92.3%), eyelid retraction (84.6%), acquired epiblepharon (69.2%), corneal erosion (53.8%), and lagophthalmos (53.8%). None had optic neuropathy or strabismus. Mean exophthalmometry was 17.8?mm (SD?±?3.6?mm, range 13.0-27.0). Ten patients (76.9%) had mild disease, 3 patients (23.1%) had moderate disease and none had severe disease. Clinically significant Active disease as defined in adults (VISA Inflammatory Score >4/10), was not observed in any patient. The majority of the patients were treated conservatively. One patient underwent bilateral orbital decompression for severe proptosis, while two patients underwent bilateral lower epiblepharon correction with good outcomes. None required corticosteroids (oral/pulsed). Conclusion: Clinical manifestations in pediatric TED are relatively mild and respond well to conservative therapy. Orbital decompression is rarely required but may be considered in children with severe proptosis. Mean exophthalmometry values are lower in East-Asian pediatric TED as compared to Caucasians. Symptomatic acquired epiblepharon, usually associated with keratopathy, is commonly seen in East-Asian pediatric TED; thus, increased awareness among ophthalmologists and pediatricians should be emphasized.
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Differences of left ventricular systolic deformation in hypertensive patients with and without apical hypertrophic cardiomyopathy.
Cardiovasc Ultrasound
PUBLISHED: 08-03-2013
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We tested the hypothesis that the apical myocardial mechanics differ from those of other ventricular segments in hypertensive patients with and without apical hypertrophic cardiomyopathy (ApHCM).
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Genome-wide patterns of genetic variation in two domestic chickens.
Genome Biol Evol
PUBLISHED: 07-02-2013
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Domestic chickens are excellent models for investigating the genetic basis of phenotypic diversity, as numerous phenotypic changes in physiology, morphology, and behavior in chickens have been artificially selected. Genomic study is required to study genome-wide patterns of DNA variation for dissecting the genetic basis of phenotypic traits. We sequenced the genomes of the Silkie and the Taiwanese native chicken L2 at ?23- and 25-fold average coverage depth, respectively, using Illumina sequencing. The reads were mapped onto the chicken reference genome (including 5.1% Ns) to 92.32% genome coverage for the two breeds. Using a stringent filter, we identified ?7.6 million single-nucleotide polymorphisms (SNPs) and 8,839 copy number variations (CNVs) in the mapped regions; 42% of the SNPs have not found in other chickens before. Among the 68,906 SNPs annotated in the chicken sequence assembly, 27,852 were nonsynonymous SNPs located in 13,537 genes. We also identified hundreds of shared and divergent structural and copy number variants in intronic and intergenic regions and in coding regions in the two breeds. Functional enrichments of identified genetic variants were discussed. Radical nsSNP-containing immunity genes were enriched in the QTL regions associated with some economic traits for both breeds. Moreover, genetic changes involved in selective sweeps were detected. From the selective sweeps identified in our two breeds, several genes associated with growth, appetite, and metabolic regulation were identified. Our study provides a framework for genetic and genomic research of domestic chickens and facilitates the domestic chicken as an avian model for genomic, biomedical, and evolutionary studies.
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Plasma P-selectin predicts long-term cardiovascular events in hospitalized patients with suspected coronary artery disease and preserved left ventricular function: a 10-year follow-up study.
Biomed J
PUBLISHED: 06-29-2013
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A variety of biomarkers have been investigated on their values to predict cardiovascular outcomes, such as high-sensitivity C-reactive protein (hs-CRP), fibrinogen, troponin-I (TnI), and soluble P-selectin (sP-sel). By a design of head-to-head comparison, this study sought to figure out the long-term prognostic values of these parameters in patients hospitalized with suspected coronary artery disease.
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Fluviimonas pallidilutea gen. nov., sp. nov., a new member of the family Cytophagaceae isolated from a freshwater river.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 05-17-2013
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A bacterial strain designated TQQ6(T) was isolated from a freshwater river in Taiwan and characterized using a polyphasic taxonomy approach. Cells of strain TQQ6(T) were strictly aerobic, Gram-staining-negative, poly-?-hydroxybutyrate-containing, non-motile, non-spore-forming, long rods surrounded by a thick capsule and forming pale orange colonies. Growth occurred at 20-40 °C (optimum, 25 °C), at pH 7.0-9.0 (optimum, pH 8.0) and with 0-0.5?% NaCl (optimum, 0?%). The predominant fatty acids were iso-C15?:?0, summed feature 3 (comprising C16?:?1?6c and/or C16?:?1?7c), iso-C17?:?0 3-OH, C16?:?1?5c and C16?:?0. The major isoprenoid quinone was MK-7 and the DNA G+C content was 42.2 mol%. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, two uncharacterized aminophospholipids and three uncharacterized phospholipids. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain TQQ6(T) represents a distinct phyletic line that reflects a novel generic status within the family Cytophagaceae with relatively low sequence similarities (less than 90?%) to members of other genera with validly published names. On the basis of the genotypic and phenotypic data, strain TQQ6(T) represents a new genus and novel species of the family Cytophagaceae, for which the name Fluviimonas pallidilutea gen. nov., sp. nov. is proposed. The type strain is TQQ6(T) (?=?BCRC 80447(T)?=?LMG 27056(T)?=?KCTC 32035(T)).
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Central nicotinic acetylcholine receptor involved in Ca(2+) -calmodulin-endothelial nitric oxide synthase pathway modulated hypotensive effects.
Br. J. Pharmacol.
PUBLISHED: 11-16-2011
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Recent evidence has suggested that nicotine decreases blood pressure (BP) and heart rate (HR) in the nucleus tractus solitarii (NTS), indicating that nicotinic acetylcholine receptors (nAChRs) play an important role in BP control in the NTS. However, the signalling mechanisms involved in nAChR-mediated depressor effects in the NTS are unclear. Hence, the aim of this study was to investigate these signalling mechanisms.
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The effects of gold nanoparticles in wound healing with antioxidant epigallocatechin gallate and ?-lipoic acid.
Nanomedicine
PUBLISHED: 03-31-2011
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Topical applications of antioxidant agents in cutaneous wounds have attracted much attention. Gold nanoparticles (AuNPs), epigallocatechin gallate (EGCG), and ?-lipoic acid (ALA) were shown to have antioxidative effects and could be helpful in wound healing. Their effects in Hs68 and HaCaT cell proliferation and in mouse cutaneous wound healing were studied. Both the mixture of EGCG + ALA (EA) and AuNPs + EGCG + ALA (AuEA) significantly increased Hs68 and HaCaT proliferation and migration. Topical AuEA application accelerated wound healing on mouse skin. Immunoblotting of wound tissue showed significant increase of vascular endothelial cell growth factor and angiopoietin-1 protein expression, but no change of angiopoietin-2 or CD31 after 7 days. After AuEA treatment, CD68 protein expression decreased and Cu/Zn superoxide dismutase increased significantly in the wound area. In conclusion, AuEA significantly accelerated mouse cutaneous wound healing through anti-inflammatory and antioxidation effects. This study may support future studies using other antioxidant agents in the treatment of cutaneous wounds.
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Peroxisome proliferator-activated receptor ? downregulates the expression of the receptor for advanced glycation end products and pro-inflammatory cytokines in the kidney of streptozotocin-induced diabetic mice.
Eur J Pharm Sci
PUBLISHED: 02-21-2011
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Activation of peroxisome proliferator-activated receptor ? (PPAR?) plays board beneficial effects in treating metabolic syndrome. The aim of this study is to examine whether PPAR? alters the expression of the receptor for advanced glycation end products (RAGE) and downstream pro-inflammatory cytokines in diabetic nephropathy. Streptozotocin-induced diabetic mice (STZ mice) were injected with a PPAR? agonist, L-165041 (5 ?M/kg, intraperitoneal) once daily for 10 days and high glucose-treated cultured HEK cells were also used. After L-165041 treatment, serum TNF?, IL-6 and IL-1 levels were significantly decreased in STZ mice. RAGE mRNA and protein expression were both decreased by L-165041 in kidney tissues of STZ mice. The high glucose incubation increased NF-?B, RAGE and IL-6 expressions in HEK293 cells. These effects were inhibited by L-165041 and specific RAGE siRNA transfection. This study demonstrated that PPAR? may play a beneficial role in preventing diabetic nephropathy. Its downstream signaling may include RAGE and NF-?B pathway. Target on PPAR? will provide new meaningful therapies to patients with diabetic nephropathy.
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Correlation between fouling propensity of soluble extracellular polymeric substances and sludge metabolic activity altered by different starvation conditions.
Bioresour. Technol.
PUBLISHED: 07-22-2010
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Soluble extracellular polymeric substances (EPSs) cause membrane fouling in membrane bioreactors (MBRs), correlated with MBR sludge characteristics. Effects of F/M ratios on the evolution of soluble EPSs, fouling propensity of supernatants, and sludge metabolic activity were measured in this study in a two-period sequencing batch reactor (SBR). The experimental results show that fouling propensity was directly correlated with soluble-EPS concentration and composition. Sludge that had entirely lost active cells by long-term starvation released 64.4 ± 0.9 mg/L of humic acids, which caused a rapid increase in membrane resistance (40.67 ± 2.24 × 10(11) m(-1)) during fouling tests. During short-term starvation, induced by incubation at a normal to low F/M ratio of 0.05 d(-1), sludge can use previously secreted utilization-associated products (UAPs) to maintain endogenous respiration. Therefore, the strategies of accumulating sludge and prolonging sludge retention time in MBRs may create long-term starvation and promote membrane fouling.
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Evolution in the Drosophila ananassae species subgroup.
Fly (Austin)
PUBLISHED: 04-12-2009
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Drosophila ananassae and its relatives have many advantages as a model of genetic differentiation and speciation. In this report, we examine evolutionary relationships in the ananassae species subgroup using a multi-locus molecular data set, karyotypes, meiotic chromosome configuration, chromosomal inversions, morphological traits, and patterns of reproductive isolation. We describe several new taxa that are the closest known relatives of D. ananassae. Analysis of Y-chromosomal and mitochondrial haplotypes, shared chromosome arrangements, pre-mating isolation and hybrid male sterility suggests that these taxa represent a recent evolutionary radiation and may experience substantial gene flow. We discuss possible evolutionary histories of these species and give a formal description of one of them as D. parapallidosa Tobari sp. n. The comparative framework established by this study, combined with the recent sequencing of the D. ananassae genome, will facilitate future studies of reproductive isolation, phenotypic variation and genome evolution in this lineage.
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Involvement of NMDA receptors in nicotine-mediated central control of hypotensive effects.
Chin J Physiol
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It is known that enrichment of glutamatergic transmission in the nucleus tractus solitarii (NTS) plays an important role in central cardiovascular regulation. Our previous study demonstrated that nicotine decreased blood pressure and heart rate in the NTS probably acting via the nicotinic acetylcholine receptors (nAChRs)-Ca²?-calmodulin-eNOS-NO signaling pathway. The possible relationship between glutamate and nicotine in the NTS for cardiovascular regulation is poorly understood. This study investigated the involvement of glutamate receptors in the cardiovascular effects of nicotine in the NTS. Nicotine (a non-selective nAChRs agonist), MK801 (a non-competitive NMDA receptor antagonist), APV (a competitive NMDA receptor antagonist), or NBQX (a selective AMPA receptor antagonist) was microinjected into the NTS of anesthetized Wistar-Kyoto rats. Microinjection of nicotine (1.5 pmol) into the NTS produced decreases in blood pressure and heart rate. The hypotensive and bradycardic effects of nicotine were abolished by prior administration of MK801 (1 nmol) and APV (10 nmol), but was completely restored after 60 min of recovery. In contrast, prior administration of NBQX (10 pmol) into the NTS did not alter the cardiovascular effects of nicotine. The nitrate (served as total NO) production in response to nicotine microinjection into the NTS was suppressed by prior administration of APV. These results suggest that the hypotensive and bradycardic effects of nicotine in the NTS might be mediated through NMDA receptors, and that the nAChRs-NMDA receptor-NO pathway could be involved.
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Non-invasive cardiac index monitoring during cardiopulmonary functional testing provides additional prognostic value in patients after acute heart failure.
Int Heart J
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The prognostic value of parameters derived from a cardiopulmonary exercise test (CPET) is well established in patients stabilized after acute heart failure (HF). Under multidisciplinary disease management, this study sought to test whether noninvasive cardiac output (CO) monitoring (NICOM) during the CPET provides additional prognostic value. In total, 131 patients stabilized after acute HF agreed to undergo the CPET with NICOM. Outcome follow-up focused on composite events of death and HF-related rehospitalization. Patients with a peak cardiac index (CI) of ? 4.5 L/minute/ m(2) (n = 32), compared to those with a peak CI of > 4.5 L/minute/m(2) (n = 99), had higher incidences of diabetes mellitus (DM) and hypertension, but had lower hemoglobin levels, estimated glomerular filtration rates (eGFR), oxygen uptake efficiency slope (OUES), and peak oxygen uptake (VO(2)). During the 1.2 ± 0.7 years of follow-up, there were 8 (6.1%) deaths, and 16 (12.2%) HF-related rehospitalizations. In a Cox univariable analysis, a lower event-free survival was associated with a history of DM, a higher Ve/VCO(2) slope, lower peak VCO(2) and eGFR, and a peak CI of ? 4.5 L/minute/ m(2) (P < 0.05). The Cox multivariable analysis showed that the Ve/VCO(2) slope (hazard ratio (HR) = 1.08, 95% confidence interval (CI): 1.01~1.16, P = 0.02) and peak CI of ? 4.5 L/minute/m(2 )(HR = 3.26, 95% CI: 1.18~9.01, P = 0.02) were significant independent predictors. In conclusion, NICOM during the CPET was demonstrated to provide prognostic information in addition to traditional risk factors, biomarkers, and other well-established CPET parameters.
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Genetic basis of a violation of Dollos Law: re-evolution of rotating sex combs in Drosophila bipectinata.
Genetics
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Phylogenetic analyses suggest that violations of "Dollos law"--that is, re-evolution of lost complex structures--do occur, albeit infrequently. However, the genetic basis of such reversals has not been examined. Here, we address this question using the Drosophila sex comb, a recently evolved, male-specific morphological structure composed of modified bristles. In some species, sex comb development involves only the modification of individual bristles, while other species have more complex "rotated" sex combs that are shaped by coordinated migration of epithelial tissues. Rotated sex combs were lost in the ananassae species subgroup and subsequently re-evolved, ?12 million years later, in Drosophila bipectinata and its sibling species. We examine the genetic basis of the differences in sex comb morphology between D. bipectinata and D. malerkotliana, a closely related species with a much simpler sex comb representing the ancestral condition. QTL mapping reveals that >50% of this difference is controlled by one chromosomal inversion that covers ?5% of the genome. Several other, larger inversions do not contribute appreciably to the phenotype. This genetic architecture suggests that rotating sex combs may have re-evolved through changes in relatively few genes. We discuss potential developmental mechanisms that may allow lost complex structures to be regained.
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Topical treatment with anti-oxidants and Au nanoparticles promote healing of diabetic wound through receptor for advance glycation end-products.
Eur J Pharm Sci
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Impairment in diabetic wound healing constitutes an enormous biomedical burden. The receptor for advanced glycation end-products (RAGE) expression in the diabetic cutaneous wound may play a key role. However, the relationship between RAGE expression and topical application of anti-oxidant agents with gold nanoparticles (AuNP) in cutaneous diabetic wounds remains unclear. We tested the 3-5 nm AuNP, epigallocatechin gallate (EGCG), and ?-lipoic acid (ALA) could change the RAGE expression and be helpful in diabetic wound. The mixture of AuNP+EGCG+ALA (AuEA) significantly attenuated the AGE-induced RAGE protein expression in fibroblasts (Hs68). Topical EGCG+ALA (EA) and AuEA application accelerated wound healing on diabetic mouse skin and decreased the RAGE expression. Vascular endothelial growth factor but not angiopoietin-1 significantly increased after EA or AuEA treatment for 7 days. Angiopoietin-2 significantly decreased at day 7 in AuEA group. Furthermore, immunoblotting of diabetic wound tissue showed significant decrease of CD68 expression from day 3 to day 7. The results suggest that combination of AuNP, EGCG, and ALA significantly accelerated diabetic cutaneous wound healing through angiogenesis regulation and anti-inflammatory effects. Blockade of RAGE by anti-oxidant agents and nanoparticles may restore effective wound healing in diabetic ulcer.
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Dengue virus serotype 2 blocks extracellular signal-regulated kinase and nuclear factor-?B activation to downregulate cytokine production.
PLoS ONE
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Dengue virus (DENV) infection is the most common mosquito-borne viral disease threatening human health around the world. Type I interferon (IFN) and cytokine production are crucial in the innate immune system. We previously reported that DENV serotype 2 (DENV-2) induced low levels of interferon regulatory factor 3 and NF-?B activation, thus leading to reduced production of IFN-? in the early phase of infection. Here, we determined whether DENV infection not only hampers type I IFN activation but also cytokine production triggered by Toll-like receptor (TLR) signaling.
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The chicken frizzle feather is due to an ?-keratin (KRT75) mutation that causes a defective rachis.
PLoS Genet.
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Feathers have complex forms and are an excellent model to study the development and evolution of morphologies. Existing chicken feather mutants are especially useful for identifying genetic determinants of feather formation. This study focused on the gene F, underlying the frizzle feather trait that has a characteristic curled feather rachis and barbs in domestic chickens. Our developmental biology studies identified defects in feather medulla formation, and physical studies revealed that the frizzle feather curls in a stepwise manner. The frizzle gene is transmitted in an autosomal incomplete dominant mode. A whole-genome linkage scan of five pedigrees with 2678 SNPs revealed association of the frizzle locus with a keratin gene-enriched region within the linkage group E22C19W28_E50C23. Sequence analyses of the keratin gene cluster identified a 69 bp in-frame deletion in a conserved region of KRT75, an ?-keratin gene. Retroviral-mediated expression of the mutated F cDNA in the wild-type rectrix qualitatively changed the bending of the rachis with some features of frizzle feathers including irregular kinks, severe bending near their distal ends, and substantially higher variations among samples in comparison to normal feathers. These results confirmed KRT75 as the F gene. This study demonstrates the potential of our approach for identifying genetic determinants of feather forms.
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Correlation between bio-hydrogen production and polyhydroxybutyrate (PHB) synthesis by Rhodopseudomonas palustris WP3-5.
Bioresour. Technol.
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The aim of this study was to determine the competition between H(2) production and polyhydroxybutyrate (PHB) accumulation of Rhodopseudomonas palustris WP3-5 when grown on six different substrates. From the results, strain WP3-5 can utilize acetate, propionate, malate, and lactate to produce H(2) but can only synthesize PHB on acetate and propionate. The substrate conversion efficiency (SCE) on acetate and propionate increased significantly after the maximum PHB content was achieved, illustrating a competition for reducing power when PHB synthesis occurred. However, when strain WP3-5 was cultivated at suboptimal pH values on acetate, the synthesized PHB prevented strain WP3-5 from the stress of the inappropriate pH and retained H(2) producing efficiency as at optimal pH value. Consequently, although PHB synthesis does compete with H(2) production in R. palustris WP3-5, it is still conducive to H(2) production when strain WP3-5 is in a stressful condition.
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