Genomic analysis of Tibetan ground tits identifies molecular adaptations associated with cooperative breeding.

Cooperative breeding is a sophisticated altruistic social behavior that helps social animals to adapt to harsh environments. The Tibetan ground tit, Pseudopodoces humilis, is a high-altitude bird endemic to the Tibetan plateau. Recently, it has become an exciting system for studying the evolution of facultative cooperative breeding. To test for molecular adaptations associated with cooperative breeding, we resequenced the whole genome of ground tits from 6 wild populations that display remarkable variation in the frequency of cooperative breeding. Population structure analyses showed that the 6 populations were divided into 4 lineages, which is congruent with the major geographical distribution of the sampling sites. Using genome-wide selective sweep analysis, we identified putative positively selected genes (PSGs) in groups of tits that displayed high and low cooperative breeding rates. The total number of PSGs varied from 146 to 722 in high cooperative breeding rate populations, and from 272 to 752 in low cooperative breeding rate populations. Functional enrichment analysis of these PSGs identified several significantly enriched ontologies related to oxytocin signaling, estrogen signaling, and insulin secretion. PSGs involved in these functional ontologies suggest that molecular adaptations in hormonal regulation may have played important roles in shaping the evolution of cooperative breeding in the ground tit. Taken together, our study provides candidate genes and functional ontologies involved in molecular adaptations associated with cooperative breeding in Tibetan ground tits, and calls for a better understanding of the genetic roles in the evolution of cooperative breeding.

Local Adaptation of Bitter Taste and Ecological Speciation in a Wild Mammal.

Sensory systems are attractive evolutionary models to address how organisms adapt to local environments that can cause ecological speciation. However, tests of these evolutionary models have focused on visual, auditory, and olfactory senses. Here, we show local adaptation of bitter taste receptor genes in two neighboring populations of a wild mammal-the blind mole rat Spalax galili-that show ecological speciation in divergent soil environments. We found that basalt-type bitter receptors showed higher response intensity and sensitivity compared with chalk-type ones using both genetic and cell-based functional analyses. Such functional changes could help animals adapted to basalt soil select plants with less bitterness from diverse local foods, whereas a weaker reception to bitter taste may allow consumption of a greater range of plants for animals inhabiting chalk soil with a scarcity of food supply. Our study shows divergent selection on food resources through local adaptation of bitter receptors, and suggests that taste plays an important yet underappreciated role in speciation.

ACE2 receptor usage reveals variation in susceptibility to SARS-CoV and SARS-CoV-2 infection among bat species.

Bats are the suggested natural hosts for severe acute respiratory syndrome coronavirus (SARS-CoV) and the causal agent of the coronavirus disease 2019 (COVID-19) pandemic, SARS-CoV-2. The interaction of viral spike proteins with their host receptor angiotensin-converting enzyme 2 (ACE2) is a critical determinant of potential hosts and cross-species transmission. Here we use virus-host receptor binding and infection assays to examine 46 ACE2 orthologues from phylogenetically diverse bat species, including those in close and distant contact with humans. We found that 24, 21 and 16 of them failed to support infection by SARS-CoV, SARS-CoV-2 or both viruses, respectively. Furthermore, we confirmed that infection assays in human cells were consistent with those in two bat cell lines. Additionally, we used genetic and functional analyses to identify critical residues in bat ACE2 receptors associated with viral entry restrictions. Our results suggest that many bat species may not be the potential hosts of one or both viruses and that no correlation was identified between proximity to humans and probability of being natural hosts of SARS-CoV or SARS-CoV-2. This study demonstrates dramatic variation in susceptibility to SARS-CoV and SARS-CoV-2 infection among bat species and adds knowledge towards a better understanding of coronavirus-bat interaction.

Diet and Adaptive Evolution of Alanine-Glyoxylate Aminotransferase Mitochondrial Targeting in Birds.

Adaptations to different diets represent a hallmark of animal diversity. The diets of birds are highly variable, making them an excellent model system for studying adaptive evolution driven by dietary changes. To test whether molecular adaptations to diet have occurred during the evolution of birds, we examined a dietary enzyme alanine-glyoxylate aminotransferase (AGT), which tends to target mitochondria in carnivorous mammals, peroxisomes in herbivorous mammals, and both mitochondria and peroxisomes in omnivorous mammals. A total of 31 bird species were examined in this study, which included representatives of most major avian lineages. Of these, 29 have an intact mitochondrial targeting sequence (MTS) of AGT. This finding is in stark contrast to mammals, which showed a number of independent losses of the MTS. Our cell-based functional assays revealed that the efficiency of AGT mitochondrial targeting was greatly reduced in unrelated lineages of granivorous birds, yet it tended to be high in insectivorous and carnivorous lineages. Furthermore, we found that proportions of animal tissue in avian diets were positively correlated with mitochondrial targeting efficiencies that were experimentally determined, but not with those that were computationally predicted. Adaptive evolution of AGT mitochondrial targeting in birds was further supported by the detection of positive selection on MTS regions. Our study contributes to the understanding of how diet drives molecular adaptations in animals, and suggests that caution must be taken when computationally predicting protein subcellular targeting.

[Comparison of the prognosis of intertrochanteric fracture with different surgical methods in elderly: a retrospective survival analysis].

OBJECTIVE: To determine the difference of post-operative mortality between ORIF (open reduction internal fixation) and hip replacement for the treatment of intertrochanteric fracture in elderly by using survival analysis. METHODS: The clinical data of 110 patients above 60 years old who underwent surgical treatment (ORIF or hip replacement) for the intertrochanteric fracture between April 2003 and May 2013 were retrospectively analyzed. Among the patients, 83 cases were treated with ORIF (ORIF group), there were 32 males and 51 females, aged from 61.44 to 98.75 years old with an average of (78.52 ± 7.98) years old; and 27 cases were treated with hip replacement (arthroplasty group), there were 8 males and 19 females, aged from 71.82 to 96.54 years old with an average of (79.99 ± 6.11) years old. A survival analysis was performed on the clinical data by using SPSS 110 software. The survival rate of 1-year,2-year, 5-year and the mean survival time for the total patients, the mortality rate of 1-year, 2-year in each group, the survival rate of 1-year, 2-year and mean survival time and survival curve in each group were included. RESULTS: All wounds achieved primary healing and no deaths were found in stay hospital. All patients were followed up from 1 to 125 months with an average of (46.93 ± 29.53) months. Among all 110 cases, 31 were dead and 79 survived. The survival rate of 1-year, 2-year and 5-year was (90.7 ± 2.8)%, (82.5 ± 3.9)% and (57.6 ± 6.5)%, respectively,while the ensemble mean survival time was (84.137 ± 5.902) months. The mortality rate of 1-year, 2-year in ORIF group was 7.2% and 12.0%, respectively; and in arthroplasty group, there was 14.8% and 25.9%, respectively. There was no significant difference in mortality rate of 1-year and 2-year between two groups. According to the survival analysis of the ORIF group, the survival rate of 1-year, 2-year was (92.6 ± 2.9)%, and (85.8 ± 4.3)%, respectively, and the mean survival time was (87.508 ± 6.063) months. In arthroplasty group, the survival rate of 1-year, 2-year was (85.2 ± 6.8)% and (73.9 ± 8.5)%,and the mean survival time was (67.294 ± 11.180) months. There was significant difference in mean survival time between two groups (P < 0.05). CONCLUSION: ORIF can achieve a better postoperative survival compare with hip replacement in treating intertrochanteric fracture in elderly.

Epidemiologic features and environmental risk factors of severe fever with thrombocytopenia syndrome, Xinyang, China.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in rural areas of Central China in 2009, caused by a novel bunyavirus, SFTS virus (SFTSV). The disease usually presents as fever, thrombocytopenia, and leukocytopenia, with case-fatality rates ranging from 2.5% to 30%. Haemaphysalis longicornis was suspected to be the most likely vector of SFTSV. By the end of 2012, the disease had expanded to 13 provinces of China. SFTS patients have been reported in Japan and South Korea, and a disease similar to SFTS has been reported in the United States. METHODOLOGY/PRINCIPAL FINDINGS: We characterized the epidemiologic features of 504 confirmed SFTS cases in Xinyang Region, the most severely SFTS-afflicted region in China from 2011 to 2012, and assessed the environmental risk factors. All cases occurred during March to November, with the epidemic peaking from May to July. The patients' ages ranged from 7 to 87 years (median 61 years), and the annual incidence increased with age (χ2 test for trend, P<0.001). The female-to-male ratio of cases was 1.58, and 97.0% of the cases were farmers who resided in the southern and western parts of the region. The Poisson regression analysis revealed that the spatial variations of SFTS incidence were significantly associated with the shrub, forest, and rain-fed cropland areas. CONCLUSIONS: The distribution of SFTS showed highly significant temporal and spatial heterogeneity in Xinyang Region, with the majority of SFTS cases being elderly farmers who resided in the southern and western parts of the region, mostly acquiring infection between May and July when H. longicornis is highly active. The shrub, rain-fed, and rain-fed cropland areas were associated with high risk for this disease.

Clinical progression and predictors of death in patients with severe fever with thrombocytopenia syndrome in China.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease of which the clinical progression and factors related to death are still unclear. OBJECTIVE: To identify the clinical progression of SFTS and explore predictors of fatal outcome throughout the disease progress. STUDY DESIGN: A prospective study was performed in a general hospital located in Xinyang city during 2011-2013. Confirmed SFTS patients were recruited and laboratory parameters that were commonly evaluated in clinical practice were collected. The clinical progression was determined based on analysis of dynamic profiles and Friedman's test. At each clinical stage, the laboratory features that could be used to predict fatal outcome of SFTS patients were identified by stepwise discriminant analysis. RESULTS: Totally 257 survivors and 54 deceased SFTS patients were recruited and the data of 11 clinical and laboratory parameters along their entire disease course were consecutively collected. Three clinical stages (day 1-5 post onset, day 6-11 post onset and day 12 to hospital discharge) were determined based on distinct clinical parameters evaluations. Multivariate discriminant analysis at each clinical stage disclosed the indicators of the fatal outcome as decreased platelet counts at early stage, older age and increased AST level at middle stage, and decreased lymphocyte percentage and increased LDH level at late stage. CONCLUSIONS: The significant indicators at three clinical stages could be used to assist identifying the patients with high risk of death. This knowledge might help to perform supportive treatment and avoid fatality.

Case-fatality ratio and effectiveness of ribavirin therapy among hospitalized patients in china who had severe fever with thrombocytopenia syndrome.

BACKGROUND: The wide distribution and high case-fatality ratio of severe fever with thrombocytopenia syndrome (SFTS) have made it a significant public health problem. This study was designed to identify the predictors of fatal outcomes and to evaluate the effectiveness of antiviral therapy in treating SFTS virus (SFTSV)-infected patients. METHODS: A cross-sectional study was performed in a general hospital located in Xinyang city, whereas the largest number of patients with SFTS in China were treated during 2011-2012. The primary outcome for the treatment effect analysis was death. Other outcomes included sequential platelet levels and viral loads observed throughout the hospitalization and the interval between the initiation of ribavirin therapy and the return of the platelet count to a normal level. RESULTS: A total of 311 SFTSV-infected patients were included in the study. The most frequent clinical presentations were fever, weakness, myalgia, and gastrointestinal symptoms. Each patient had thrombocytopenia, leukopenia, or both. The case-fatality ratio (CFR) was 17.4% (95% confidence interval [CI], 13.1%-21.6%). Older age (odds ratio [OR], 1.061; 95% CI, 1.023-1.099; P = .001), decreased level of consciousness (OR, 5.397; 95% CI, 2.660-10.948; P < .001), and elevated levels of lactate dehydrogenase (>1200 U/L; OR, 2.620; 95% CI, 1.073-6.399; P = .035) and creatine kinase (>800 U/L; OR, 2.328; 95% CI, 1.129-4.800; P = .022) were significantly associated with fatal outcome. The CFRs were similar between patients who received ribavirin and those who did not. Ribavirin treatment showed no significant effect on either platelet counts or viral loads during hospitalization of patients with fatal or nonfatal cases. CONCLUSIONS: These findings can improve knowledge about the characteristics of patients with fatal outcomes and the use of antiviral drug for SFTS.

[The clinical characteristics of 169 cases of severe fever with thrombocytopenia syndrome].

OBJECTIVE: To analyze the clinical characteristics of severe fever with thrombocytopenia syndrome (SFTS) so as to improve the recognition of the emerging infectious disease. METHODS: A retrospective analysis was performed upon clinical manifestations, laboratory test results and prognostic features of 169 patients with SFTS admitted to the 154 Hospital, Chinese People's Liberation Army from October 2010 to May 2011. The patients were divided into moderate disease group and severe disease group according to the prognosis. The differences between two groups were compared to explore the prognostic indicator of severe type. RESULTS: All patients with SFTS inhabited in hilly ground with history of field work. The main clinical symptoms were severe fever (98.8%, 167/169), headache (52.1%, 88/169), muscle soreness (95.9%, 162/169), nausea (73.4%, 124/169), vomiting (67.5%, 114/169), coughing (61.5%, 104/169), etc. Superficial lymph node enlargement with haphalgesia was observed in 45.0% (76/169) patients. Petechia or ecchymosis was observed in 36.7% (62/169) patients. Critical patients were mainly aged > 60 years, associated with nerve and circulatory system syndrome, prominent hemoptysis, dyspnea, and nearly 73.3% (22/30) of severe thrombocytopenia. Serum levels of aspartate aminotransferase, creatinine and urea nitrogen were significantly higher in severe disease group than those in moderate disease group [235 (47 - 1750) U/L vs 88 (14 - 2000) U/L, 997(281 - 2601) U/L vs 399 (26 - 2633) U/L, 101 (62 - 291) µmol/L vs 70 (26 - 205) µmol/L, 7.0 (2.2 - 20.0) mmol/L vs 4.8 (1.4 - 18.5) mmol/L, all P values < 0.001]. CONCLUSION: Nerves system syndrome, transaminase and urea nitrogen are risk factors of prognosis of severe SFTS to whom deserves paying attention.

[Determination of rat serum emodin level by microemulsion liquid chromatography with direct sample loading].

OBJECTIVE: To establish a microemulsion liquid chromatography system with direct sample loading for determining the serum level of emodin in rats. METHODS: The separation was performed on C18 column (Hypersil BDS, 5 µm,150 mm×4.6 mm) with the microemulsion mobile phase consisting of 3.3% (w/V) SDS, 6.6% (V/V) n-butyl alcohol, and 1.0% (V/V) octane and water. The flow rate was 1.0 ml/min and the detection wavelength was 254 nm. RESULTS: The linear range of emodin detection was 0.333-5.32 µg/ml. The average recovery was 99.65% with a RSD of 3.60%. The limit of quantification was 0.1386 µg/mL. CONCLUSION: Microemulsion liquid chromatography system with direct sample loading allows simple, accurate and rapid determination of emodin in rat serum.