Molecular adaptations underlying high-frequency hearing in the brain of CF bats species.

BACKGROUND: The majority of bat species have developed remarkable echolocation ability, especially for the laryngeally echolocating bats along with high-frequency hearing. Adaptive evolution has been widely detected for the cochleae in the laryngeally echolocating bats, however, limited understanding for the brain which is the central to echolocation signal processing in the auditory perception system, the laryngeally echolocating bats brain may also undergo adaptive changes. RESULT: In order to uncover the molecular adaptations related with high-frequency hearing in the brain of laryngeally echolocating bats, the genes expressed in the brain of Rhinolophus ferrumequinum (CF bat) and Myotis pilosus (FM bat) were both detected and also compared. A total of 346,891 genes were detected and the signal transduction mechanisms were annotated by the most abundant genes, followed by the transcription. In hence, there were 3,088 DEGs were found between the two bat brains, with 1,426 highly expressed in the brain of R. ferrumequinum, which were significantly enriched in the neuron and neurodevelopmental processes. Moreover, we found a key candidate hearing gene, ADCY1, playing an important role in the R. ferrumequinum brain and undergoing adaptive evolution in CF bats. CONCLUSIONS: Our study provides a new insight to the molecular bases of high-frequency hearing in two laryngeally echolocating bats brain and revealed different nervous system activities during auditory perception in the brain of CF bats.

Patterns and correlates of potential range shifts of bat species in China in the context of climate change.

Climate change may diminish biodiversity; thus, it is urgent to predict how species' ranges may shift in the future by integrating multiple factors involving more taxa. Bats are particularly sensitive to climate change due to their high surface-to-volume ratio. However, few studies have considered geographic variables associated with roost availability and even fewer have linked the distributions of bats to their thermoregulation and energy regulation traits. We used species distribution models to predict the potential distributions of 12 bat species in China under current and future greenhouse gas emission scenarios (SSP1-2.6 and SSP5-8.5) and examined factors that could affect species' range shifts, including climatic, geographic, habitat, and human activity variables and wing surface-to-mass ratio (S-MR). The results suggest that Ia io, Rhinolophus ferrumequinum, and Rhinolophus rex should be given the highest priority for conservation in future climate conservation strategies. Most species were predicted to move northward, except for I. io and R. rex, which moved southward. Temperature seasonality, distance to forest, and distance to karst or cave were the main environmental factors affecting the potential distributions of bats. We found significant relationships between S-MR and geographic distribution, current potential distribution, and future potential distribution in the 2050s. Our work highlights the importance of analyzing range shifts of species with multifactorial approaches, especially for species traits related to thermoregulation and energy regulation, to provide targeted conservation strategies.

Patrones y correlaciones de los cambios potenciales en la distribución de las especies de murciélago de China en el contexto del cambio climático Resumen El cambio climático puede disminuir la biodiversidad, por lo que es urgente pronosticar cómo puede cambiar en el futuro la distribución de las especies mediante la integración de múltiples factores que involucren a más taxones. Los murciélagos son particularmente sensibles al cambio climático debido a que tienen una gran proporción superficie­volumen. Sin embargo, hay pocos estudios que han considerado las variables asociadas con la disponibilidad de nidos y son todavía menos los que han conectado la distribución de los murciélagos con sus rasgos de termorregulación y regulación de energía. Usamos modelos de distribución de especies para pronosticar la distribución potencial de doce especies de murciélago en China bajo escenarios actuales y futuros de emisión de gases de efecto invernadero (SSP1­2.6 y SSP5­8.5) y analizamos los factores que podrían afectar el cambio en la distribución de las especies, incluyendo las variables climáticas, geográficas, de hábitat y de actividad humana y la proporción entre la superficie del ala y la masa (P S­M). Los resultados sugieren que Ia io, Rhinolophus ferrumequinum y R. rex deberían ser la mayor prioridad de conservación para las estrategias de conservación climáticas en el futuro. Pronosticamos que la mayoría de las especies se desplazarían al norte, a excepción de I. io y R. rex, que se desplazarían hacia el sur. Los principales factores que afectaron la distribución potencial de los murciélagos fueron la estacionalidad de la temperatura, la distancia al bosque y la distancia a la cueva o al karst. Encontramos una relación significativa entre la P S­M y la distribución geográfica, la distribución potencial actual y la distribución potencial para la década de 2050. Nuestra investigación destaca la importancia del análisis de los cambios de distribución de las especies con enfoques multifactoriales, especialmente para los rasgos de especie relacionados con la termorregulación y la regulación de energía, para proporcionar estrategias de conservación focalizadas.

Predictive Value and Immunological Role of the HSPA5 Gene in Cervical Cancer.

Cervical cancer (CC) ranks fourth among women's malignancies worldwide and seriously affects women's health. HSPA5 is a heat shock protein, also known as glucose regulatory protein 78 (GRP78). Upregulation of HSPA5 has been reported to be closely associated with multiple types of tumors. However, the specific role of HSPA5 in cervical cancer has not been discovered. In our study, we explored the prognostic value of HSPA5 in CC. Here, we analyzed the (TCGA) and (UCSC) databases, the analysis of HSPA5 in many tumors types was conducted with the "wilcox. test" method. A False Discovery Rate (FDR) value < 0.05 and Log2 | (fold change, FC) |> 1 were set as the cutoffs. "*", "**", and "***" indicate FDR < 0.05, < 0.01, and < 0.001, respectively, and further used human cervical cancer cells for q-PCR and western blotting detection. q-PCR and western blotting results showed that HSPA5 was highly expressed in cervical cancer cells, while it was expressed at low levels in normal cells (P < 0.05).We also analyzed the immunohistochemical data. immunohistochemical analysis results showed that HSPA5 was highly expressed in human cervical cancer, while it was expressed at low levels in normal tissues (P < 0.05). Analysis in TCGA-UCSC showed that the proportion of G3 in the group with high expression of HSPA5 was relatively high (P < 0.05). Enrichment analysis and survival analysis showed that the increased expression of HSPA5 in cervical cancer was related to the survival of CC and was involved in the regulation of biological behavior and molecular signaling pathways of cervical cancer. The correlation analysis of immune checkpoint and immune infiltration showed that HSPA5 was involved in the regulation of immune process of cervical cancer (P < 0.05). Drug sensitivity correlation analysis showed that HSPA5 was a sensitive target for tumor drugs (P < 0.05). In brief, those results suggest that HSPA5 can act as an oncogene of CC development and can serve as an effective predictive biomarker in cervical cancer.

Excessive heavy metal enrichment disturbs liver functions through the gut microbe in the great Himalayan leaf-nosed bat (Hipposideros armiger).

Heavy metal residues in natural ecosystems have emerged as a significant global environmental problem requiring urgent resolution. Because these elements are non-biodegradable, organisms can accumulate excessive levels of heavy metal elements into their tissues. Previous studies suggest that prolonged exposure to heavy metal enrichment poses comprehensive toxicity to various organs in vertebrates. However, few studies have focused on elucidating the molecular mechanism underlying the hepatotoxic effects of heavy metal enrichment in Chiroptera. In this study, 10 Hipposideros armiger individuals were dissected from Yingde City (YD, relatively pollution-free) and Chunwan City (CW, excessive heavy metals emission). Environmental samples were also obtained. To investigate the mechanism of heavy metal toxicity in bat livers, we employed a combination of multi-omics, pathology, and molecular biology methods. Our results revealed significant enrichment of Cd and Pb in the bat livers and food sources in the CW group (P<0.05). Furthermore, prolonged accumulation of heavy metals disrupted hepatic transcription profiles associated with the solute carriers family, the ribosome pathway, ATP usage, and heat shock proteins. Excessive heavy metal enrichment also altered the relative abundance of typical gut microbe taxa significantly (P<0.05), inhibiting tight-junction protein expression. We observed a significant decrease in the levels of superoxide dismutase, glutathione peroxidase, and glutathione (P<0.05), along with elevated reactive oxygen species (ROS) density and malondialdehyde content following excessive heavy metal enrichment. Additionally, hepatic fat accumulation and inflammation injuries were present under conditions of excessive heavy metal enrichment, while the contents of metabolism biomarkers significantly decreased (P<0.05). Consequently, prolonged heavy metal enrichment can induce hepatotoxicity by disturbing the microbes-gut-liver axis and hepatic transcription modes, leading to a decrease in overall metabolic activity in bats. Our study offers strategies for biodiversity conservation and highlights the importance of addressing environmental pollution to raise public awareness.

Seasonal assembly of skin microbiota driven by neutral and selective processes in the greater horseshoe bat.

Skin microbiota play an important role in protecting bat hosts from the fungal pathogen Pseudogymnoascus destructans, which has caused dramatic bat population declines and extinctions. Recent studies have provided insights into the bacterial communities of bat skin, but variation in skin bacterial community structure in the context of the seasonal dynamics of fungal invasion, as well as the processes that drive such variation, remain largely unexplored. In this study, we characterized bat skin microbiota over the course of the bat hibernation and active season stages and used a neutral model of community ecology to determine the relative roles of neutral and selective processes in driving microbial community variation. Our results showed significant seasonal shifts in skin community structure, as well as less diverse microbiota in hibernation than in the active season. Skin microbiota were influenced by the environmental bacterial reservoir. During both the hibernation and active season stages, more than 78% of ASVs in bat skin microbiota were consistent with neutral distribution, implying that neutral processes, that is, dispersal or ecological drift contributing the most to shifts in skin microbiota. In addition, the neutral model showed that some ASVs were actively selected by the bats from the environmental bacterial reservoir, accounting for approximately 20% and 31% of the total community during hibernation and active season stages, respectively. Overall, this research provides insights into the assemblage of bat-associated bacterial communities and will aid in the development of conservation strategies against fungal disease.

Contrasting laboratory and field outcomes of bat-moth interactions.

Predator-prey interactions are important but difficult to study in the field. Therefore, laboratory studies are often used to examine the outcomes of predator-prey interactions. Previous laboratory studies have shown that moth hearing and ultrasound production can help prey avoid being eaten by bats. We report here that laboratory behavioural outcomes may not accurately reflect the outcomes of field bat-moth interactions. We tested the success rates of two bat species capturing moths with distinct anti-bat tactics using behavioural experiments. We compared the results with the dietary composition of field bats using next-generation DNA sequencing. Rhinolophus episcopus and Rhinolophus osgoodi had a lower rate of capture success when hunting for moths that produce anti-bat clicks than for silent eared moths and earless moths. Unexpectedly, the success rates of the bats capturing silent eared moths and earless moths did not differ significantly from each other. However, the field bats had a higher proportion of silent eared moths than that of earless moths and that of clicking moths in their diets. The difference between the proportions of silent eared moths and earless moths in the bat diets can be explained by the difference between their abundance in bat foraging habitats. These findings suggest that moth defensive tactics, bat countertactics and moth availability collectively shape the diets of insectivorous bats. This study illustrates the importance of using a combination of behavioural experiments and molecular genetic techniques to reveal the complex interactions between predators and prey in nature.

Seasonal variation of population and individual dietary niche in the avivorous bat, Ia io.

The variation in niche breadth can affect how species respond to environmental and resource changes. However, there is still no clear understanding of how seasonal variability in food resources impacts the variation of individual dietary diversity, thereby affecting the dynamics of a population's dietary niche breadth. Optimal foraging theory (OFT) and the niche variation hypothesis (NVH) predict that when food resources are limited, the population niche breadth will widen or narrow due to increased within-individual dietary diversity and individual specialization or reduced within-individual dietary diversity, respectively. Here, we used DNA metabarcoding to examine the composition and seasonality of diets of the avivorous bat Ia io. Furthermore, we investigated how the dietary niches changed among seasons and how the population niche breadth changed when the availability of insect resources was reduced in autumn. We found that there was differentiation in dietary niches among seasons and a low degree of overlap, and the decrease of insect resource availability and the emergence of ecological opportunities of nocturnal migratory birds might drive dietary niche shifts toward birds in I. io. However, the population's dietary niche breadth did not broaden by increasing the within-individual dietary diversity or individual specialization, but rather became narrower by reducing dietary diversity via predation on bird resources that served as an ecological opportunity when insect resources were scarce in autumn. Our findings were consistent with the predictions of OFT, because birds as prey for bats provided extremely different resources from those of insects in size and nutritional value. Our work highlights the importance of size and quality of prey resources along with other factors (i.e., physiological, behavioral, and life-history traits) in dietary niche variation.

Environmental reservoir dynamics predict global infection patterns and population impacts for the fungal disease white-nose syndrome.

Disease outbreaks and pathogen introductions can have significant effects on host populations, and the ability of pathogens to persist in the environment can exacerbate disease impacts by fueling sustained transmission, seasonal epidemics, and repeated spillover events. While theory suggests that the presence of an environmental reservoir increases the risk of host declines and threat of extinction, the influence of reservoir dynamics on transmission and population impacts remains poorly described. Here we show that the extent of the environmental reservoir explains broad patterns of host infection and the severity of disease impacts of a virulent pathogen. We examined reservoir and host infection dynamics and the resulting impacts of Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome, in 39 species of bats at 101 sites across the globe. Lower levels of pathogen in the environment consistently corresponded to delayed infection of hosts, fewer and less severe infections, and reduced population impacts. In contrast, an extensive and persistent environmental reservoir led to early and widespread infections and severe population declines. These results suggest that continental differences in the persistence or decay of P. destructans in the environment altered infection patterns in bats and influenced whether host populations were stable or experienced severe declines from this disease. Quantifying the impact of the environmental reservoir on disease dynamics can provide specific targets for reducing pathogen levels in the environment to prevent or control future epidemics.

Full-Length Transcriptome of the Great Himalayan Leaf-Nosed Bats (Hipposideros armiger) Optimized Genome Annotation and Revealed the Expression of Novel Genes.

The Great Himalayan Leaf-nosed bat (Hipposideros armiger) is one of the most representative species of all echolocating bats and is an ideal model for studying the echolocation system of bats. An incomplete reference genome and limited availability of full-length cDNAs have hindered the identification of alternatively spliced transcripts, which slowed down related basic studies on bats' echolocation and evolution. In this study, we analyzed five organs from H. armiger for the first time using PacBio single-molecule real-time sequencing (SMRT). There were 120 GB of subreads generated, including 1,472,058 full-length non-chimeric (FLNC) sequences. A total of 34,611 alternative splicing (AS) events and 66,010 Alternative Polyadenylation (APA) sites were detected by transcriptome structural analysis. Moreover, a total of 110,611 isoforms were identified, consisting of 52% new isoforms of known genes and 5% of novel gene loci, as well as 2112 novel genes that have not been annotated before in the current reference genome of H. armiger. Furthermore, several key novel genes, including Pol, RAS, NFKB1, and CAMK4, were identified as being associated with nervous, signal transduction, and immune system processes, which may be involved in regulating the auditory nervous perception and immune system that helps bats to regulate in echolocation. In conclusion, the full-length transcriptome results optimized and replenished existing H. armiger genome annotation in multiple ways and offer advantages for newly discovered or previously unrecognized protein-coding genes and isoforms, which can be used as a reference resource.

Comparative analysis of the daily liver transcriptomes in wild nocturnal bats.

BACKGROUND: Mammals rely on the circadian clock network to regulate daily systemic metabolism and physiological activities. The liver is an important peripheral organ in mammals, and it has a unique circadian rhythm regulation process. As the only mammals that can fly, bats have attracted much research attention due to their nocturnal habits and life histories. However, few research reports exist concerning the circadian rhythms of bat liver gene expression and the relevant biological clock regulation mechanisms in the liver. RESULTS: In this study, the expression levels of liver genes of Asian particolored bats were comparatively analyzed using RNA-seq at four different time points across 24 h. A total of 996 genes were found to be rhythmic, accounting for 65% of the total number of expressed genes. The critical circadian rhythm genes Bmal1, Rev-erbα, Cry, and Ror in the liver exhibited different expression patterns throughout the day, and participated in physiological processes with rhythmic changes, including Th17 cell differentiation (ko04659), antigen processing and presentation (ko04612), the estrogen signaling pathway (ko04915), and insulin resistance (ko04931). In addition, previous studies have found that the peroxisome proliferator-activated receptor (PPAR) metabolic signaling pathway (ko03320) may play a vital role in the rhythmic regulation of the metabolic network. CONCLUSIONS: This study is the first to demonstrate diurnal changes in bat liver gene expression and related physiological processes. The results have thus further enriched our understanding of bats' biological clocks.

Bacterial community dynamics on bats and the implications for pathogen resistance.

The bats skin microbiota plays an important role in reducing pathogen infection, including the deadly fungal pathogen Pseudogymnoascus destructans, the causative agent of white-nose syndrome. However, the dynamic of skin bacterial communities response to environmental perturbations remains poorly described. We characterized skin bacterial community over time and space in Rhinolophus ferrumequinum, a species with high resistance to the infection with P. destructans. We collected environmental covariate data to determine what factors influenced changes in community structure. We observed significant temporal and spatial shifts in the skin bacterial community, which was mainly associated with variation in operational taxonomic units. The skin bacterial community differed by the environmental microbial reservoirs and was most influenced by host body condition, bat roosting temperature and geographic distance between sites, but was not influenced by pathogen infection. Furthermore, the skin microbiota was enriched in particular taxa with antifungal abilities, such as Enterococcus, Burkholderia, Flavobacterium, Pseudomonas, Corynebacterium and Rhodococcus. And specific strains of Pseudomonas, Corynebacterium and Rhodococcus even inhibited P. destructans growth. Our findings provide new insights in characterizing the variation in bacterial communities can inform us about the processes of driving community assembly and predict the host's ability to resist or survive pathogen infection.

Long noncoding RNA SNHG9 facilitates growth of glioma stem-like cells via miR-326/SOX9 axis.

BACKGROUND: Glioma stem-like cells (GSCs) are greatly responsible for the progression of glioma. Long noncoding RNAs (lncRNAs) play an important role in glioma tumor progression. This study aims to explore the role and underlying mechanism of lncRNA SNHG9 in regulating GSC cell growth. METHODS: GSCs were obtained from glioma cells (U87 and U251) and referred to as GSC-87 and GSC-251, respectively. The interactions between miR-326 and SNHG9 or SOX9 were analyzed using luciferase reporter assay. Cell growth of GSCs was evaluated by EdU assay and sphere formation assay. RESULTS: SNHG9 expression was significantly higher in GSC-87 and GSC-251 cells than in U87 and U251 cells. SNHG9 overexpression promoted GSC cell growth, whereas SNHG9 knockdown inhibited GSC cell growth. Mechanistically, SNHG9 acted as a competitive endogenous RNA of miR-326 to elevate the expression of SOX9, a direct target of miR-326. Moreover, transfection with miR-326 inhibitor counteracted SNHG9 knockdown-mediated inhibition of GSC cell growth. CONCLUSIONS: SNHG9 facilitates growth of GSCs via the miR-326/SOX9 axis. This study provides a promising therapeutic target for glioma treatment.

Low-level gastrokine 2 promoted progress of NSCLC and as a potential biomarker.

BACKGROUND: Gastrokine 2 (GKN2) is significantly downregulated in non-small cell lung cancer (NSCLC) tissues than in normal tissues (NT), as assessed by mRNA microassay; however, the mechanism and clinical value of GKN2 is unknown in NSCLC. METHODS: A total of 60 NSCLC samples and corresponding NT samples were prospectively collected GKN2 expression in NSCLC tissues was estimated. Also, the expression level of GKN2 promoter methylation and correlation with clinical data in NSCLC patients from public databases were analyzed. Cytology experiments were also carried out. RESULTS: The GKN2 mRNA and protein expression level in NSCLC was significantly lower than that in the NT, and the GKN2 expression level in large tumors NSCLC was significantly lower than that in the small tumor group. Public data showed that expression of GKN2 in LUAD with P53 mutation group was lower than that of the P53 non-mutation group, and GKN2 promoter methylation level of LUAD was significantly higher than its NT and close to age and clinical stage. Cell migration, invasion, and proliferation ability of GKN2 overexpressed were lower in A549 and PC9 groups than those in GKN2 overexpressed A549 and PC9 negative control groups, while the percentage of apoptotic cells increased in the GKN2 overexpressed A549 and PC9 groups. The DNMT3B mRNA expression levels were higher in PC9 and A549 cells than BEAS-2B cells. CONCLUSION: The overexpression of GKN2 significantly inhibited cell proliferation, migration, and invasion and promoted apoptosis. Low-level GKN2 promoted the progression of NSCLC via DNMT3B and is expected to be a biomarker for NSCLC.

Full-Length Transcriptome of Myotis pilosus as a Reference Resource and Mining of Auditory and Immune Related Genes.

Rickett's big-footed bat, Myotis pilosus, which belongs to the family Vespertilionida, is the only known piscivorous bat in East Asia. Accurate whole genome and transcriptome annotations are essential for the study of bat biological evolution. The lack of a whole genome for M. pilosus has limited our understanding of the molecular mechanisms underlying the species' evolution, echolocation, and immune response. In the present work, we sequenced the entire transcriptome using error-corrected PacBio single-molecule real-time (SMRT) data. Then, a total of 40 GB of subreads were generated, including 29,991 full-length non-chimeric (FLNC) sequences. After correction by Illumina short reads and de-redundancy, we obtained 26,717 error-corrected isoforms with an average length of 3018.91 bp and an N50 length of 3447 bp. A total of 1528 alternative splicing (AS) events were detected by transcriptome structural analysis. Furthermore, 1032 putative transcription factors (TFs) were identified, with additional identification of several long non-coding RNAs (lncRNAs) with high confidence. Moreover, several key genes, including PRL-2, DPP4, Glul, and ND1 were also identified as being associated with metabolism, immunity, nervous system processes, and auditory perception. A multitude of pattern recognition receptors was identified, including NLR, RLR, SRCR, the antiviral molecule IRF3, and the IFN receptor subunit IFNAR1. High-quality reference genomes at the transcriptome level may be used to quantify gene or transcript expression, evaluate alternative splicing levels, identify novel transcripts, and enhance genome annotation in bats.

Podoplanin is dispensable for mineralized tissue formation and maintenance in the Swiss outbred mouse background.

Podoplanin, PDPN, is a mucin-type transmembrane glycoprotein widely expressed in many tissues, including lung, kidney, lymph nodes, and mineralized tissues. Its function is critical for lymphatic formation, differentiation of type I alveolar epithelial lung cells, and for bone response to biomechanical loading. It has previously been shown that Pdpn null mice die at birth due to respiratory failure emphasizing the importance of Pdpn in alveolar lung development. During the course of generation of Pdpn mutant mice, we found that most Pdpn null mice in the 129S6 and C57BL6/J mixed genetic background die at the perinatal stage, similar to previously published studies with Pdpn null mice, while all Pdpn null mice bred with Swiss outbred mice survived. Surviving mutant mice in the 129S6 and C57BL6/J mixed genetic background showed alterations in the osteocyte lacunocanalicular network, especially reduced osteocyte canaliculi in the tibial cortex with increased tibial trabecular bone. However, adult Pdpn null mice in the Swiss outbred background showed no overt differences in their osteocyte lacunocnalicular network, bone density, and no overt differences when challenged with exercise. Together, these data suggest that genetic variations present in the Swiss outbred mice compensate for the loss of function of PDPN in lung, kidney, and bone.

Effects and mechanism of lncRNA-27785.1 that regulates TGF-ß1 of Sika deer on antler cell proliferation.

Transforming growth factor (TGF-ß) plays an important role in the development of deer antlers. The purpose of this study was to investigate the role of long noncoding RNA in the transcriptional regulation of TGF-ß1 and its relationship with the proliferation and differentiation of antler chondrocytes. High-throughput sequencing was used to screen lncRNAs related to TGF-ß1. Next, the overexpression plasmid and interference sequence of target lncRNA27785.1 were constructed and transfected into chondrocytes. We found that lncRNA27785.1 inhibited the proliferation and migration of chondrocytes and delayed the transition of cells from G1 to S phase. qRT-PCR and Western blot analysis indicated that the overexpression of lncRNA27785.1 may downregulate mRNA and protein expression of TGF-BR2, Smad3, pSmad3, and Smad4. Our findings highlight lncRNA27785.1 as an inhibitor of chondrocytes proliferation and differentiation by negatively regulating the TGF-ß/Smad signaling pathway; this implicates an important regulatory role for long noncoding RNA in the regeneration of antler.

Social calls influence the foraging behavior in wild big-footed myotis.

BACKGROUND: Why a variety of social animals emit foraging-associated calls during group foraging remains an open question. These vocalizations may be used to recruit conspecifics to food patches (i.e. food advertisement hypothesis) or defend food resources against competitors (food defence hypothesis), presumably depending on food availability. Insectivorous bats rely heavily on vocalizations for navigation, foraging, and social interactions. In this study, we used free-ranging big-footed myotis (Myotis macrodactylus Temminck, 1840) to test whether social calls produced in a foraging context serve to advertise food patches or to ward off food competitors. Using a combination of acoustic recordings, playback experiments with adult females and dietary monitoring (light trapping and DNA metabarcoding techniques), we investigated the relationship between insect availability and social vocalizations in foraging bats. RESULTS: The big-footed myotis uttered low-frequency social calls composed of 7 syllable types during foraging interactions. Although the dietary composition of bats varied across different sampling periods, Diptera, Lepidoptera, and Trichoptera were the most common prey consumed. The number of social vocalizations was primarily predicted by insect abundance, insect species composition, and echolocation vocalizations from conspecifics. The number of conspecific echolocation pulses tended to decrease following the emission of most social calls. Feeding bats consistently decreased foraging attempts and food consumption during playbacks of social calls with distinctive structures compared to control trials. The duration of flight decreased 1.29-1.96 fold in the presence of social calls versus controls. CONCLUSIONS: These results support the food defence hypothesis, suggesting that foraging bats employ social calls to engage in intraspecific food competition. This study provides correlative evidence for the role of insect abundance and diversity in influencing the emission of social calls in insectivorous bats. Our findings add to the current knowledge of the function of social calls in echolocating bats.

Territorial calls of the bat Hipposideros armiger may encode multiple types of information: body mass, dominance rank and individual identity.

In highly vocal species, territorial aggression is often accompanied using vocalizations. These vocalizations can play a critical role in determining the outcome of male-male agonistic interactions. For this, vocalizations of contestants must contain information that is indicative of each competitor's fighting ability as well as its identity, and also contestants must be able to perceive information about the physical attributes, quality and identity of the vocalizer. Here, we used adult male Great Himalayan leaf-nosed bats (Hipposideros armiger) to test whether territorial calls encoded honest information about a caller's physical attributes, quality and individual identity. We did this by exploring the relationships between territorial calls and two potential indices of fighting ability: body mass and dominance rank. Using synchronized audio-video recording, we monitored bat territorial calls and dominance rank of 16 adult male H. armiger in the laboratory. Additionally, habituation-dishabituation playback experiments were performed to test for vocal discrimination. Results showed that body mass was negatively related to minimum frequency and positively related to syllable duration. Dominance score was also negatively related to minimum frequency and positively related to peak frequency. Furthermore, a discriminant function analysis suggested that territorial calls encode an individual signature. Therefore, our data show that males have the ability to utilize this vocal individual signature to discriminate between vocalizing males. In short, territorial calls of male H. armiger contain information about body mass, dominance rank and individual identity, and contestants are probably capable of perceiving this information and may use it to make appropriate decisions during agonistic interactions.

Does public fear that bats spread COVID-19 jeopardize bat conservation?

With >1 400 species, bats comprise the second-largest order of mammals and provide critical ecological services as insect consumers, pollinators, and seed dispersers. Yet, bats are frequently associated with infectious human diseases such as SARS, MERS, and Ebola. As early as the end of January 2020, several virological studies have suggested bats as a probable origin for SARS-CoV-2, the causative agent of COVID-19. How does the public view the role of bats in COVID-19? Here we report pilot data collected shortly after the outbreak of COVID-19 using two online surveys, combined with a conservation intervention experiment, primarily on people who are receiving or have received higher education in China. We found that 84% of the participants of an online survey (n = 13 589) have misunderstood the relationship between bats and COVID-19, which strengthened negative attitudes towards bats. Knowledge of bats, gender, and education level of the participants affected their attitudes towards bats. Participants who indicated a better knowledge of bats had a more positive attitude towards bats. The proportion of female participants who had negative attitudes towards bats was higher than that of male participants. Participants with a higher education level indicated a more positive attitude towards bats after the outbreak of COVID-19. A specially prepared bat conservation lecture improved peoples' knowledge of bats and the positive attitudes, but failed to correct the misconception that bats transmit SARS-CoV-2 to humans directly. We suggest that the way virologists frame the association of bats with diseases, the countless frequently inaccurate media coverages, and the natural perceptual bias of bats carrying and transmitting diseases to humans contributed to the misunderstandings. This probably led to a rise in the events of evicting bats from dwellings and structures by humans and the legislative proposal for culling disease-relevant wildlife in China. A better understanding of the relationship between disease, wildlife and human health could help guide the public and policymakers in an improved program for bat conservation.

The clinical efficacy of argon-helium knife cryoablation combined with nivolumab in the treatment of advanced non-small cell lung cancer.

To investigate the clinical safety and efficacy of argon-helium knife cryoablation combined with nivolumab in the treatment of advanced non-small cell lung cancer (NSCLC), 64 patients with advanced NSCLC were retrospectively reviewed. From July 2019 to December 2019, all patients received argon-helium knife cryoablation combined with nivolumab (cryo-nivolumab group, n = 32) or cryoablation alone (cryoablation group, n = 32) at Guangzhou Fuda Cancer Hospital. Short-term efficacy, adverse effects, immune function, tumor markers cytokeratin 21-1 (CYFRA21-1), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE) and circulating tumor cells (CTCs) levels were compared between the two groups. Baseline characteristics were balanced between the two groups. All adverse effects were manageable and no significant difference was noted between the two groups (P > 0.05). Patients in cryo-nivolumab group had a significant improvement in immune function and short-term efficacy (P < 0.05). The levels of CTCs and tumor markers CYFRA21-1 and NSE in cryo-nivolumab group were reduced significantly (P < 0.05). Argon-helium knife cryoablation combined with nivolumab was well tolerated and safe and was superior to cryoablation alone in improving clinical efficacy in patients with advanced NSCLC.