COMPARISON OF OXIRIS AND CONVENTIONAL CONTINUOUS RENAL REPLACEMENT THERAPY IN MANAGING SEVERE ABDOMINAL INFECTIONS: IMPACT ON SEPTIC SHOCK MORTALITY.

ABSTRACT: Objective: The objective of this study is to assess and compare the efficacy of oXiris with conventional continuous renal replacement therapy (CRRT) in managing severe abdominal infections. Methods: A retrospective analysis encompassing cases from 2017 to 2023 was conducted at the Department of Critical Care Medicine within the First Affiliated Hospital of Fujian Medical University. Parameters including heart rate (HR), mean arterial pressure (MAP), oxygenation index, lactate (Lac), platelet count, neutrophil ratio, procalcitonin, C-reactive protein (CRP), interleukin 6 (IL-6), norepinephrine dosage, Acute Physiology and Chronic Health Evaluation II (APACHE II), and Sequential Organ Failure Assessment (SOFA) were recorded prior to treatment initiation, at 24 h, and 72 h after treatment for both the oXiris and conventional CRRT groups. In addition, the duration of respiratory support, CRRT treatment, length of stay in the intensive care unit (ICU), total hospitalization period, and mortality rates at 14 and 28 days for both groups were recorded. Results: 1) Within the conventional CRRT group, notable enhancement was observed solely in Lac levels at 24 h after treatment compared with pretreatment levels. In addition, at 72 h after treatment, improvements were evident in HR, Lac, CRP, and IL-6 levels. 2) Conversely, the oXiris group exhibited improvements in HR, MAP, Lac, oxygenation index, neutrophil ratio, and IL-6 at 24 h after treatment when compared with baseline values. In addition, reductions were observed in APACHE II and SOFA scores. At 72 h after treatment, all parameters demonstrated enhancement except for platelet count. 3) Analysis of the changes in the indexes (Δ) between the two groups at 24 h after treatment revealed variances in HR, MAP, Lac, norepinephrine dosage, CRP levels, IL-6 levels, APACHE II scores, and SOFA scores. 4) The Δ indexes at 72 h after treatment indicated more significant improvements following oXiris treatment for both groups, except for procalcitonin. 5) The 14-day mortality rate (24.4%) exhibited a significant reduction in the oXiris group when compared with the conventional group (43.6%). However, no significant difference was observed in the 28-day mortality rate between the two groups. 6) Subsequent to multifactorial logistic regression analysis, the results indicated that oXiris treatment correlated with a noteworthy decrease in the 14-day and 28-day mortality rates associated with severe abdominal infections, by 71.3% and 67.6%, respectively. Conclusion: oXiris demonstrates clear advantages over conventional CRRT in the management of severe abdominal infections. Notably, it reduces the fatality rates, thereby establishing itself as a promising and potent therapeutic option.

Factors Associated with Re-Displacement after Nonsurgical Treatment of Distal Radius Fractures in Adults: A Retrospective Study.

OBJECTIVE: Closed reduction combined with external fixation is a frequently utilized approach for treating distal radial fractures in adults. Nonetheless, the potential for re-displacement following external fixation remains. Analyzing the factors influencing re-displacement after nonsurgical treatment of distal radial fractures in adults is vital for preventing re-displacement and making prognostic assessments. METHODS: A retrospective analysis was performed on 884 patients who underwent nonsurgical treatment for distal radius fractures in the reduction room of the Orthopedics and Traumatology Department of Integrated Traditional Chinese and Western Medicine at Tianjin Hospital, Tianjin, China, between July 2019 and December 2022. Patients were categorized into two groups, namely displaced and nondisplaced, based on radiographic outcomes. Factors affecting fracture re-displacement were examined, including sex, age, side, AO/OTA type, external fixation, and radiographic outcomes at pre-reduction and immediate reduction. Logistic regression analysis was employed to identify the risk factors for fracture re-displacement, and ROC curves were constructed. RESULTS: Among the 884 patients, 563 (63.69%) experienced re-displacement after fracture reduction. There were no statistically significant differences (p > 0.05) between the two groups in terms of gender, external fixation method, and palmar tilt angle at pre-reduction and immediate reduction, while significant differences (p < 0.05) were observed in age, side, AO/OTA type, and radial inclination, radial length, and radiographic outcomes of ulnar variance at pre-reduction and immediate reduction. Multifactorial logistic regression analysis revealed that age (odds ratio [OR] = 1.027, p < 0.001), AO/OTA type (OR = 2.327, p = 0.005), ulnar variance at pre-reduction (OR = 1.142, p = 0.048), and ulnar variance at immediate reduction (OR = 1.685, p < 0.001) were significant factors (p < 0.05) associated with re-displacement following nonoperative treatment of adult distal radius fractures. For patients aged ≥60 years, the amount of missing radiographic outcomes was positively correlated with age. The receiver operating characteristic curve demonstrated that age ≥65.5 years, ulnar variance >3.26 mm at pre-reduction, and ulnar variance >2.055 mm at immediate reduction were high-risk factors for fracture re-displacement. CONCLUSIONS: Nonsurgical treatment of distal radius fractures exhibits a higher rate of re-displacement. Age, AO/OTA type, pre-reduction, and immediate reduction ulnar variance are key factors predicting fracture re-displacement.

New Attempts to Inhibit Methicillin-Resistant Staphylococcus aureus Biofilm? A Combination of Daptomycin and Azithromycin.

Objective: To investigate the antibacterial impact of daptomycin and azithromycin in vitro on methicillin-resistant Staphylococcus aureus (MRSA) biofilm. Methods: (1) Measure the strain growth curve and the biofilm formation curve. (2) Determine the minimum inhibitory concentrations (MICs) of daptomycin and azithromycin. (3) Investigate the antibacterial impact of the combination of daptomycin and azithromycin. (4) Perform the evaluation of the intervention impact of antimicrobial agents on MRSA biofilm. (5) Observe the biofilm after intervention with the antibacterial agent. Results: (1) MRSA exhibited three phases: lag phase (0-4 h), logarithmic growth (4-8 h) and stationary phase after 18 h; its biofilm began to form at 6 h, semi-matured at 24 h, and reached maturity after 48 h. (2) The MICs of daptomycin and azithromycin were 8 µg/mL and greater than 256 µg/mL, respectively. (3) The combination of daptomycin and azithromycin has an additive effect on MRSA (Fractional Inhibitory Concentration Index [FICI] 0.625) (FICI = MIC of drug A in combination/MIC of drug A alone + MIC of drug B in combination/MIC of drug B alone). Evaluation criteria: Synergistic effect is considered when FICI ≤ 0.5; additive effect is considered when 0.5 < FICI ≤ 1; irrelevant effect is considered when 1 < FICI ≤ 2; antagonistic effect is considered when FICI > 2). (4) Daptomycin or azithromycin at MICs inhibited not only the growth of planktonic bacteria but also the formation of biofilm. (5) The combination of both, in which group the ratio of live/dead bacteria is low and the biofilm morphology was incomplete, was more productive than monotherapy in against biofilm. Conclusion: Both daptomycin and azithromycin have anti-MRSA biofilm activity, and daptomycin is dominant. The fact that the combination of both can significantly inhibit the further maturation of MRSA biofilm and destroy already formed biofilm demonstrates the superiority of the combination over the monotherapy.

Genomic analyses of wild argali, domestic sheep, and their hybrids provide insights into chromosome evolution, phenotypic variation, and germplasm innovation.

Understanding the genetic mechanisms of phenotypic variation in hybrids between domestic animals and their wild relatives may aid germplasm innovation. Here, we report the high-quality genome assemblies of a male Pamir argali (O ammon polii, 2n = 56), a female Tibetan sheep (O aries, 2n = 54), and a male hybrid of Pamir argali and domestic sheep, and the high-throughput sequencing of 425 ovine animals, including the hybrids of argali and domestic sheep. We detected genomic synteny between Chromosome 2 of sheep and two acrocentric chromosomes of argali. We revealed consistent satellite repeats around the chromosome breakpoints, which could have resulted in chromosome fusion. We observed many more hybrids with karyotype 2n = 54 than with 2n = 55, which could be explained by the selfish centromeres, the possible decreased rate of normal/balanced sperm, and the increased incidence of early pregnancy loss in the aneuploid ewes or rams. We identified genes and variants associated with important morphological and production traits (e.g., body weight, cannon circumference, hip height, and tail length) that show significant variations. We revealed a strong selective signature at the mutation (c.334C > A, p.G112W) in TBXT and confirmed its association with tail length among sheep populations of wide geographic and genetic origins. We produced an intercross population of 110 F2 offspring with varied number of vertebrae and validated the causal mutation by whole-genome association analysis. We verified its function using CRISPR-Cas9 genome editing. Our results provide insights into chromosomal speciation and phenotypic evolution and a foundation of genetic variants for the breeding of sheep and other animals.

Whole-Genome Resequencing of Worldwide Wild and Domestic Sheep Elucidates Genetic Diversity, Introgression, and Agronomically Important Loci.

Domestic sheep and their wild relatives harbor substantial genetic variants that can form the backbone of molecular breeding, but their genome landscapes remain understudied. Here, we present a comprehensive genome resource for wild ovine species, landraces and improved breeds of domestic sheep, comprising high-coverage (∼16.10×) whole genomes of 810 samples from 7 wild species and 158 diverse domestic populations. We detected, in total, ∼121.2 million single nucleotide polymorphisms, ∼61 million of which are novel. Some display significant (P < 0.001) differences in frequency between wild and domestic species, or are private to continent-wide or individual sheep populations. Retained or introgressed wild gene variants in domestic populations have contributed to local adaptation, such as the variation in the HBB associated with plateau adaptation. We identified novel and previously reported targets of selection on morphological and agronomic traits such as stature, horn, tail configuration, and wool fineness. We explored the genetic basis of wool fineness and unveiled a novel mutation (chr25: T7,068,586C) in the 3'-UTR of IRF2BP2 as plausible causal variant for fleece fiber diameter. We reconstructed prehistorical migrations from the Near Eastern domestication center to South-and-Southeast Asia and found two main waves of migrations across the Eurasian Steppe and the Iranian Plateau in the Early and Late Bronze Ages. Our findings refine our understanding of genome variation as shaped by continental migrations, introgression, adaptation, and selection of sheep.

Closed Reduction for the Treatment of Grade IV Supination-External Rotation Fracture of the Ankle Joint: A Retrospective Analysis.

OBJECTIVE: To investigate the curative effect of closed reduction and external fixation in the treatment of grade IV supination-external rotation fractures of the ankle joint. METHODS: Fifty-six patients treated with closed reduction and external fixation from February 2016 to March 2020 were included in this retrospective study, all with sprains. After receiving nerve block anesthesia, the patient underwent closed reduction under C-arm fluoroscopy, and the ankle joint was fixed in a dorsiflexion-inversion position with casting and splints after the end of the fracture met the reduction standard by fluoroscopy. One week and four weeks after the reduction treatment, oblique axial and coronal MR scans of the ankle joint were performed to determine the degree of injury and healing of the inferior tibiofibular syndesmosis; anteroposterior and lateral X-rays of the ankle joint (including the ankle acupoints) were regularly reviewed to observe the fracture alignment and healing. Combined with the images and physical examination, the patients were instructed to undergo ankle weight-bearing rehabilitation training when they met the clinical healing standard, and at the last follow-up, the Mazur ankle evaluation and grading system were used for evaluation. After the reduction, the images were evaluated according to the Leeds standard. The image healing of fracture was evaluated by callus growth criteria. RESULTS: The follow-up period of patients ranged from 11 to 58 months, with an average of 26.8 months. The clinical healing time was (8.51 ± 2.12) weeks. The excellent and good rating after reduction was 82.1%, and the excellent and good rating during clinical fracture healing was 73.2%, according to the Leeds imaging evaluation. According to the Mazur ankle evaluation and grading system, the excellent and good rating was 75.0%. Pairwise comparison of callus images at 4, 6 and 12 weeks showed statistically significant differences (P < 0.05), suggesting callus growth at different time periods. A total of 56 patients had anterior inferior tibial fibular ligament (AITFL) injuries (grade II-III), among which 11 patients had AITFL injuries combined with grade II injuries of the interosseous ligament (IOL) and 4 patients had AITFL injuries combined with grade III injuries of the IOL. CONCLUSIONS: Most of the patients with grade IV supination-external rotation fracture of the ankle joint had good prognosis after closed reduction and plaster combined with splint fixation. For patients with IOL injury who had poor prognosis, open reduction and internal fixation therapy is appropriate.

Paternal Origins and Migratory Episodes of Domestic Sheep.

The domestication and subsequent global dispersal of livestock are crucial events in human history, but the migratory episodes during the history of livestock remain poorly documented [1-3]. Here, we first developed a set of 493 novel ovine SNPs of the male-specific region of Y chromosome (MSY) by genome mapping. We then conducted a comprehensive genomic analysis of Y chromosome, mitochondrial DNA, and whole-genome sequence variations in a large number of 595 rams representing 118 domestic populations across the world. We detected four different paternal lineages of domestic sheep and resolved, at the global level, their paternal origins and differentiation. In Northern European breeds, several of which have retained primitive traits (e.g., a small body size and short or thin tails), and fat-tailed sheep, we found an overrepresentation of MSY lineages y-HC and y-HB, respectively. Using an approximate Bayesian computation approach, we reconstruct the demographic expansions associated with the segregation of primitive and fat-tailed phenotypes. These results together with archaeological evidence and historical data suggested the first expansion of early domestic hair sheep and the later expansion of fat-tailed sheep occurred ∼11,800-9,000 years BP and ∼5,300-1,700 years BP, respectively. These findings provide important insights into the history of migration and pastoralism of sheep across the Old World, which was associated with different breeding goals during the Neolithic agricultural revolution.

Chronological Changes of Viral Shedding in Adult Inpatients With COVID-19 in Wuhan, China.

BACKGROUND: In December 2019, the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) broke out in Wuhan. Epidemiological and clinical characteristics of patients with COVID-19 have been reported, but the relationships between laboratory features and viral load has not been comprehensively described. METHODS: Adult inpatients (≥18 years old) with COVID-19 who underwent multiple (≥5 times) nucleic acid tests with nasal and pharyngeal swabs were recruited from Renmin Hospital of Wuhan University, including general patients (n = 70), severe patients (n = 195), and critical patients (n = 43). Laboratory data, demographic data, and clinical data were extracted from electronic medical records. The fitted polynomial curve was used to explore the association between serial viral loads and illness severity. RESULTS: Viral load of SARS-CoV-2 peaked within the first few days (2-4 days) after admission, then decreased rapidly along with virus rebound under treatment. Critical patients had the highest viral loads, in contrast to the general patients showing the lowest viral loads. The viral loads were higher in sputum compared with nasal and pharyngeal swab (P = .026). The positive rate of respiratory tract samples was significantly higher than that of gastrointestinal tract samples (P < .001). The SARS-CoV-2 viral load was negatively correlated with portion parameters of blood routine and lymphocyte subsets and was positively associated with laboratory features of cardiovascular system. CONCLUSIONS: The serial viral loads of patients revealed whole viral shedding during hospitalization and the resurgence of virus during the treatment, which could be used for early warning of illness severity, thus improve antiviral interventions.

The Genome Landscape of Tibetan Sheep Reveals Adaptive Introgression from Argali and the History of Early Human Settlements on the Qinghai-Tibetan Plateau.

Tibetan sheep are the most common and widespread domesticated animals on the Qinghai-Tibetan Plateau (QTP) and have played an essential role in the permanent human occupation of this high-altitude region. However, the precise timing, route, and process of sheep pastoralism in the QTP region remain poorly established, and little is known about the underlying genomic changes that occurred during the process. Here, we investigate the genomic variation in Tibetan sheep using whole-genome sequences, single nucleotide polymorphism arrays, mitochondrial DNA, and Y-chromosomal variants in 986 samples throughout their distribution range. We detect strong signatures of selection in genes involved in the hypoxia and ultraviolet signaling pathways (e.g., HIF-1 pathway and HBB and MITF genes) and in genes associated with morphological traits such as horn size and shape (e.g., RXFP2). We identify clear signals of argali (Ovis ammon) introgression into sympatric Tibetan sheep, covering 5.23-5.79% of their genomes. The introgressed genomic regions are enriched in genes related to oxygen transportation system, sensory perception, and morphological phenotypes, in particular the genes HBB and RXFP2 with strong signs of adaptive introgression. The spatial distribution of genomic diversity and demographic reconstruction of the history of Tibetan sheep show a stepwise pattern of colonization with their initial spread onto the QTP from its northeastern part ∼3,100 years ago, followed by further southwest expansion to the central QTP ∼1,300 years ago. Together with archeological evidence, the date and route reveal the history of human expansions on the QTP by the Tang-Bo Ancient Road during the late Holocene. Our findings contribute to a depth understanding of early pastoralism and the local adaptation of Tibetan sheep as well as the late-Holocene human occupation of the QTP.

Contrasting Patterns of Genomic Diversity Reveal Accelerated Genetic Drift but Reduced Directional Selection on X-Chromosome in Wild and Domestic Sheep Species.

Analyses of genomic diversity along the X chromosome and of its correlation with autosomal diversity can facilitate understanding of evolutionary forces in shaping sex-linked genomic architecture. Strong selective sweeps and accelerated genetic drift on the X-chromosome have been inferred in primates and other model species, but no such insight has yet been gained in domestic animals compared with their wild relatives. Here, we analyzed X-chromosome variability in a large ovine data set, including a BeadChip array for 943 ewes from the world's sheep populations and 110 whole genomes of wild and domestic sheep. Analyzing whole-genome sequences, we observed a substantially reduced X-to-autosome diversity ratio (∼0.6) compared with the value expected under a neutral model (0.75). In particular, one large X-linked segment (43.05-79.25 Mb) was found to show extremely low diversity, most likely due to a high density of coding genes, featuring highly conserved regions. In general, we observed higher nucleotide diversity on the autosomes, but a flat diversity gradient in X-linked segments, as a function of increasing distance from the nearest genes, leading to a decreased X: autosome (X/A) diversity ratio and contrasting to the positive correlation detected in primates and other model animals. Our evidence suggests that accelerated genetic drift but reduced directional selection on X chromosome, as well as sex-biased demographic events, explain low X-chromosome diversity in sheep species. The distinct patterns of X-linked and X/A diversity we observed between Middle Eastern and non-Middle Eastern sheep populations can be explained by multiple migrations, selection, and admixture during the domestic sheep's recent postdomestication demographic expansion, coupled with natural selection for adaptation to new environments. In addition, we identify important novel genes involved in abnormal behavioral phenotypes, metabolism, and immunity, under selection on the sheep X-chromosome.

Molecular epidemiology of Clostridium difficile in two tertiary care hospitals in Shandong Province, China.

PURPOSE: The incidence and severity of Clostridium difficile infection (CDI) have markedly increased over the past decade. However, there is very limited epidemiological data on CDI in China so far, specifically no data in Shandong Province. The aim of this study was to evaluate diagnostic algorithm for CDI and to gain data on molecular epidemiology of CDI in the Shandong Province of China. MATERIALS AND METHODS: Nonrepetitive unformed fecal specimens (n=504) were investigated by the glutamate dehydrogenase (GDH), C. difficile toxin A&B (CDAB) tests and toxigenic culture. Furthermore, 85 isolates were characterized by toxin gene detection, multilocus sequence typing, ribotyping and antimicrobial susceptibility testing. RESULTS: The algorithm of combining GDH and CDAB tests could define diagnosis of 54.2% CDI cases and excluded 90% of non-CDI. Further adding the toxigenic culture to the algorithm enhanced the detection sensitivity to 100%. Toxigenic strains comprised 84.7% of isolates, including A+B+CDT- (71.8%, 61/85), A-B+CDT- (11.8%, 10/85) and A+B+CDT+ (1.2%, 1/85) isolates. RT046/ST35 (13.9%, 10/72), RT014/ST2 (12.5%, 9/72) and RT017/ST37 (12.5%, 9/72) were the more common genotypes among toxigenic C. difficile strains. The clinical severity score of A-B+CDT- toxin genes genotype (3.50±0.85) was significantly higher than the A+B+CDT- type (2.59±0.93) (P<0.05). RT046/ST35 isolates were highly prevalent and had high clinical severity scores (3.80±0.92). Variations in resistance from different sequence types (STs) were observed. Toxigenic strains showed higher resistance rates to erythromycin, clindamycin and ciprofloxacin compared to nontoxigenic strains (P<0.05). CONCLUSION: The epidemiology of C. difficile in Shandong Province differed from other regions in China. Comprehensive optimized diagnosis strategy and continuous surveillance should be established and applied in order to curb the spread of toxigenic C. difficile strains, especially for hospitalized patients.

Ectopic expression of FGF5s induces wool growth in Chinese merino sheep.

Fibroblast growth factor 5 (FGF5) has been recognized as an inhibitor to cease animal hair growth, while in contrary, FGF5 short alternative transcript (FGF5s) can induce hair growth by antagonizing FGF5 function. To investigate the role of FGF5s in wool growth in Chinese Merino sheep, we generated transgenic sheep of ectopic expression of FGF5s by injection of recombinant lentivirus into zygote. Totally 20 transgenic sheep were obtained and 12 were alive after birth. Characterization of the transgene revealed that the transgenic sheep showed variety of integrant, ranged from 2 to 11 copies of transgene. The ectopic expression of FGF5s was observed in all transgenic sheep. Further study on the effect of ectopic expression of FGF5s revealed that the wool length of transgenic sheep were significantly longer than that of non-transgenic control, with 9.17cm of transgenic lambs versus 7.58cm of control animals. Notably, besides the increase of wool length, the yearling greasy fleece weight was also concordantly greater than that of wild-type (p<0.01), with 3.22kg of transgenic sheep versus 2.17kg of control lambs (p<0.01) in average. Our results suggested that overexpression of FGF5s could stimulate wool growth and resulted in increase of wool length and greasy wool weight.

Genomic Reconstruction of the History of Native Sheep Reveals the Peopling Patterns of Nomads and the Expansion of Early Pastoralism in East Asia.

China has a rich resource of native sheep (Ovis aries) breeds associated with historical movements of several nomadic societies. However, the history of sheep and the associated nomadic societies in ancient China remains poorly understood. Here, we studied the genomic diversity of Chinese sheep using genome-wide SNPs, mitochondrial and Y-chromosomal variations in > 1,000 modern samples. Population genomic analyses combined with archeological records and historical ethnic demographics data revealed genetic signatures of the origins, secondary expansions and admixtures, of Chinese sheep thereby revealing the peopling patterns of nomads and the expansion of early pastoralism in East Asia. Originating from the Mongolian Plateau ∼5,000‒5,700 years ago, Chinese sheep were inferred to spread in the upper and middle reaches of the Yellow River ∼3,000‒5,000 years ago following the expansions of the Di-Qiang people. Afterwards, sheep were then inferred to reach the Qinghai-Tibetan and Yunnan-Kweichow plateaus ∼2,000‒2,600 years ago by following the north-to-southwest routes of the Di-Qiang migration. We also unveiled two subsequent waves of migrations of fat-tailed sheep into northern China, which were largely commensurate with the migrations of ancestors of Hui Muslims eastward and Mongols southward during the 12th‒13th centuries. Furthermore, we revealed signs of argali introgression into domestic sheep, extensive historical mixtures among domestic populations and strong artificial selection for tail type and other traits, reflecting various breeding strategies by nomadic societies in ancient China.

CRISPR/Cas9-mediated loss of FGF5 function increases wool staple length in sheep.

Fibroblast growth factor 5 (FGF5) regulates hair length in humans and a variety of other animals. To investigate whether FGF5 has similar effects in sheep, we used clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated 9 (Cas9) to generate loss-of-function mutations with the FGF5 gene in Chinese Merino sheep. A total of 16 lambs were identified with genetic mutations within the targeting locus: 13 lambs had biallelic modifications and three lambs had monoallelic modifications. Characterization of the modifications revealed that 13 were frameshift mutations that led to premature termination, whereas the other three were in-frame deletions. Thus, CRISPR/Cas9 efficiently generated loss-of-function mutations in the sheep FGF5 gene. We then investigated the effect of loss of FGF5 function on wool traits in 12 lambs and found that wool staple length and stretched length of genetically modified (GM) yearling sheep were significantly longer compared with that of wild-type (WT) control animals. The greasy fleece weight of GM yearling sheep was also significantly greater compared with that of WT sheep. Moreover, the mean fiber diameter in GM sheep showed no significant difference compared with WT sheep, suggesting that the increase in greasy fleece weight was likely attributed to the increase in wool length. The results of this study suggest that CRISPR/Cas9-mediated loss of FGF5 activity could promote wool growth and, consequently, increase wool length and yield.

Whole-Genome Sequencing of Native Sheep Provides Insights into Rapid Adaptations to Extreme Environments.

Global climate change has a significant effect on extreme environments and a profound influence on species survival. However, little is known of the genome-wide pattern of livestock adaptations to extreme environments over a short time frame following domestication. Sheep (Ovis aries) have become well adapted to a diverse range of agroecological zones, including certain extreme environments (e.g., plateaus and deserts), during their post-domestication (approximately 8-9 kya) migration and differentiation. Here, we generated whole-genome sequences from 77 native sheep, with an average effective sequencing depth of ∼5× for 75 samples and ∼42× for 2 samples. Comparative genomic analyses among sheep in contrasting environments, that is, plateau (>4,000 m above sea level) versus lowland (<100 m), high-altitude region (>1500 m) versus low-altitude region (<1300 m), desert (<10 mm average annual precipitation) versus highly humid region (>600 mm), and arid zone (<400 mm) versus humid zone (>400 mm), detected a novel set of candidate genes as well as pathways and GO categories that are putatively associated with hypoxia responses at high altitudes and water reabsorption in arid environments. In addition, candidate genes and GO terms functionally related to energy metabolism and body size variations were identified. This study offers novel insights into rapid genomic adaptations to extreme environments in sheep and other animals, and provides a valuable resource for future research on livestock breeding in response to climate change.

Mitogenomic Meta-Analysis Identifies Two Phases of Migration in the History of Eastern Eurasian Sheep.

Despite much attention, history of sheep (Ovis aries) evolution, including its dating, demographic trajectory and geographic spread, remains controversial. To address these questions, we generated 45 complete and 875 partial mitogenomic sequences, and performed a meta-analysis of these and published ovine mitochondrial DNA sequences (n = 3,229) across Eurasia. We inferred that O. orientalis and O. musimon share the most recent female ancestor with O. aries at approximately 0.790 Ma (95% CI: 0.637-0.934 Ma) during the Middle Pleistocene, substantially predating the domestication event (∼8-11 ka). By reconstructing historical variations in effective population size, we found evidence of a rapid population increase approximately 20-60 ka, immediately before the Last Glacial Maximum. Analyses of lineage expansions showed two sheep migratory waves at approximately 4.5-6.8 ka (lineages A and B: ∼6.4-6.8 ka; C: ∼4.5 ka) across eastern Eurasia, which could have been influenced by prehistoric West-East commercial trade and deliberate mating of domestic and wild sheep, respectively. A continent-scale examination of lineage diversity and approximate Bayesian computation analyses indicated that the Mongolian Plateau region was a secondary center of dispersal, acting as a "transportation hub" in eastern Eurasia: Sheep from the Middle Eastern domestication center were inferred to have migrated through the Caucasus and Central Asia, and arrived in North and Southwest China (lineages A, B, and C) and the Indian subcontinent (lineages B and C) through this region. Our results provide new insights into sheep domestication, particularly with respect to origins and migrations to and from eastern Eurasia.

[Pre-alarming apparatus for earthquake based on mid-infrared trace methane detection].

With the rapid development of gas observation technology in seismic fracture zone, in order to accurately predict the earthquake, and reduce the people's lives and property losses caused by earthquake, a mid-infrared methane sensor was designed and developed, which is based on the microscopic relation between methane release and earthquake fissures on the crustal rocks. This instrument utilizes quantum cascaded laser (QCL) operating at 7.65 µm, combined with MIR multipass herriott cell with 76 m absorption path length to obtain low detection sensitivity down to 40 nmol x mol(-1) level in 4s acquisition time. Meanwhile, to decrease the primary noise source (1/f noise), semiconductor laser frequency modulation of direct absorption technology was utilized to obtain gas detection limitation as low as 5 nmol x mol(-1) (40 s acquiring time). In field experiments, controllable vibrator was used as vibration source, a number of trace methane detectors were placed with 100 m distance interval to carry out the dynamic measurement of methane concentration on the ground surface at different distances from the vibration source. Experimental results show that the instrument can monitor the release of underground methane before the earthquake and provide a novel measure as a pre-alarming for earthquake.

Y chromosome haplotype diversity of domestic sheep (Ovis aries) in northern Eurasia.

Variation in two SNPs and one microsatellite on the Y chromosome was analyzed in a total of 663 rams representing 59 breeds from a large geographic range in northern Eurasia. SNPA-oY1 showed the highest allele frequency (91.55%) across the breeds, whereas SNPG-oY1 was present in only 56 samples. Combined genotypes established seven haplotypes (H4, H5, H6, H7, H8, H12 and H19). H6 dominated in northern Eurasia, and H8 showed the second-highest frequency. H4, which had been earlier reported to be absent in European breeds, was detected in one European breed (Swiniarka), whereas H7, which had been previously identified to be unique to European breeds, was present in two Chinese breeds (Ninglang Black and Large-tailed Han), one Buryatian (Transbaikal Finewool) and two Russian breeds (North Caucasus Mutton-Wool and Kuibyshev). H12, which had been detected only in Turkish breeds, was also found in Chinese breeds in this work. An overall low level of haplotype diversity (median h = 0.1288) was observed across the breeds with relatively higher median values in breeds from the regions neighboring the Near Eastern domestication center of sheep. H6 is the dominant haplotype in northwestern and eastern China, in which the haplotype distribution could be explained by the historical translocations of the H4 and H8 Y chromosomes to China via the Mongol invasions followed by expansions to northwestern and eastern China. Our findings extend previous results of sheep Y chromosomal genetic variability and indicate probably recent paternal gene flows between sheep breeds from distinct major geographic regions.

Caffeine and dithiothreitol delay ovine oocyte ageing.

The intracellular glutathione levels and developmental competence of aged oocytes after parthenogenetic activation, somatic cell nuclear transfer and intracytoplasmic sperm injection in the presence or absence of caffeine or dithiothreitol (DTT) were examined. The following results were found: (1) ovine oocytes were fully aged 30 h post-onset of maturation culture; (2) the appropriate concentrations of caffeine and DTT for oocyte culture were 5 mM and 1 mM, respectively; (3) when nuclear transfer-reconstructed embryos were treated with caffeine or DTT following fusion, no increase in the frequency of development to blastocyst was observed (P > 0.05), but the cell numbers of blastocysts increased (P < 0.05); (4) both caffeine and DTT increased the blastocyst formation rates of intracytoplasmic sperm-injected embryos (P < 0.05); (5) caffeine increased the glutathione content of aged oocytes (P < 0.05). The glutathione content of DTT-treated aged oocytes was higher than that of oocytes matured for 36 h (P < 0.05). In conclusion, caffeine and dithiothreitol delay oocyte ageing but only to a limited extent.

[Polymorphism at codons 136, 141 and 154 in the ovine prion protein gene in the state of Xinjiang].

Scrapie is a fatal and infectious neurodegenerating disease. The polymorphism in the prion protein (PRNP) gene is linked to the development of clinical signs of scrapie. The most important polymorphism appears to be at codons at 136(V/A), 154(H/R), and 171(H/Q/R). In this study, we investigated the polymorphisms at these codons in 746 individuals among ten sheep breeds (i.e., ALeTai, BaShiBai, BaYinBuLuKe, Celehei, DuoLang, He Tian, Chinese Merino, German Merino, Texel, and Suffolk sheep) in Xinjiang in order to evaluate the relative susceptibility of sheep to scrapie. A total of 8 alleles (i.e., ARQ, ARR, ARH, ARK, VRQ, AHR, AHQ and AHH) were observed. The alleles ARQ and ARR were found in all of the breeds with the highest frequency for allele ARQ. Allele ARH was found in eight breeds except for Suffolk and German Merino, while the ARK was only identified in ALeTai, BaShiBai, BaYinBuLuKe, and DuoLang native sheeps. The alleles VRQ, AHR, AHQ and AHH were detected exclusively in Chinese Merino with extremely low frequencies. Moreover, the genotypes contained by the eight alleles were also determined subsequently. A total of thirteen genotypes, such as ARQ/ARQ, ARQ/ARK, ARR/ARR, ARH/ARH, ARQ/ARR, ARH/ARQ, ARH/ARR, ARK/ARK, ARH/ARK, ARQ/VRQ, ARQ/AHQ, ARQ/AHR and ARH/AHH were detected. The genotype ARQ/ARQ with moderate susceptibility was found with the highest frequency among the ten breeds, whereas the genotype ARR/ARR with highest resistance to scrapie was merely identified in BaYinBuLuKe, Celehei, Chinese Merino, Texel and German Merino sheep, which had very low frequencies. In addition, the genotype VRQ/ARQ with high susceptibility was first variant reported in Chinese Merino sheep. Our data, therefore, indicate that the general genetic resistance of dominating sheep breeds in Xinjiang to scrapie was considerably low.