Livestock grazing is associated with the gut microbiota and antibiotic resistance genes in sympatric plateau pika (Ochotona curzoniae).

With the overuse of antibiotics in health care and animal husbandry, antibiotic resistance becomes a serious threat to public health. Antibiotic residues from veterinary medicine have increased the dissemination of antibiotic resistance genes (ARGs) by horizontal gene transfer globally, leading to the enrichment of ARGs in wildlife. Plateau pika (Ochotona curzoniae) is a small herbivore endemic to the Qinghai-Tibetan Plateau. Previous studies reveal that pika evolves a coprophagy behavior toward cohabitated yak, which makes the pika population a potential reservoir of ARGs. Yet, little is known about the resistome of pika under different grazing intensities. Here, we sampled the cecum content of pika from three different grazing intensity areas in the Qinghai-Tibetan Plateau to evaluate the effect of grazing on its gut microbiota and resistome. By using the 16S full-length amplicon and metagenomic sequencing, our study revealed that livestock grazing significantly altered the gut microbial community of plateau pika as compared to prohibited grazing areas. We found bacterial lineage Prevotellaceae, Lachnospirales, and RF39 increased in grazing areas. Analysis of the resistome revealed that pika from continuous grazing areas enriched a higher abundance of colistin (MCR) and streptogramin (vat) resistance genes. Moreover, we observed significant correlations between the gut microbial community, ARGs, and mobile genetic element profiles, hinting that pika gut microbiota was an important shaping force of the resistome. In future studies, the continuous monitoring of wildlife gut resistome and environmental antibiotic residues is imperative for a better understanding and for tackling the horizontal gene transfer of ARGs across the wildlife-livestock interface.

Long-Term Effects of Climate Variability on Seed Rain Dynamics of Four Fagaceae Sympatric Species in Qinling Mountains, China.

Seed rain, as the beginning of species dispersal, is a key process for forest structure and regeneration. In this study, the seed rain of four Fagaceae sympatric plant species (Castaneamollissima, Quercus aliena, Quercus variabilis, and Quercus serrata) in the Qinling Mountains were monitored for ten consecutive years, and the responses of seed rain dynamics of the four species to major climatic factors (temperature and precipitation) were analyzed. We found there were significant differences in the seed rain dynamics between C. mollissima of Castanea and the other three species of Quercus in the initial period and end period and the duration of the whole seed rain process among the 10 years. This could indicate to some extent that there was no concentrated flowering and fruiting among different plants of different genera, and they could well avoid fierce competition for similar resources and coexist in the same region. This may also be a reproductive strategy for plants. Seed rain dynamics of different plant species had different sensitivities to climate factors (temperature and precipitation), which indicated that mainly because of their different responses to climate factors, they could well avoid fierce competition for similar climate resources. In addition, the differences in seed rain dropping dynamics could reduce consumption in large numbers by seed predators, thereby promoting their own dispersal and regeneration. All of the above contribute to their better coexistence in the same domain.

Seed traits and rodent community interact to determine seed fate: evidence from both enclosure and field experiments.

Animal-mediated seed dispersal is an important ecological process in which a strong mutualism between animals and plants can arise. However, few studies have examined how a community of potential seed dispersers interacts with sympatric seed trees. We employed a series of experiments in the Qinling Mountains in both semi-natural enclosure and the field to assess the interactions among 3 sympatric rodent species and 3 Fagaceae tree seeds. Seed traits all showed similar tannin levels but markedly different physical traits and nutritional contents. We found that seeds with heavy weight, thick coat, and high nutritional contents were less likely to be eaten in situ but more often to be eaten after dispersal or hoarded by rodents. These results support both the handling time hypothesis and the high nutrition hypothesis. Surprisingly, we also found that rodents, maybe, preferred to consume seeds with low levels of crude fiber in situ, and to harvest and hoard those with high levels of crude fiber for later consumption. The sympatric rodent species, Cansumys canus, the largest rodent in our study, harvested and hoarded more Quercus variabilis seeds with high physical and nutritional traits, while Apodemus draco, the smallest rodent, harvested more Q. serrata seeds with low physical and nutritional traits, and Niviventer confucianus harvested and hoarded more Q. aliena seeds with medium physical and nutritional traits. Our study demonstrates that different seed traits play different roles in influencing the seed fate and the shaping of mutualism and predation interactions within a community of rodent species.

Analysis of risk factors for vascular cognitive impairment in patients with cerebral infarction.

This study aimed to identify risk factors for vascular cognitive impairment (VCI) in cerebral infarction patients. Associations between VCI and age, gender, blood pressure, lipid levels, glycosylated hemoglobin, atrial fibrillation, tobacco smoking, alcohol consumption, homocysteine (Hcy), and High-Sensitivity C-Reactive Protein (HS-CRP) were evaluated in patients with cerebral infarction (n = 300) using single factor analysis and multivariate logistic regression analysis. By single factor analysis, the age, glycosylated hemoglobin, atrial fibrillation, blood pressure, Hcy, HS-CRP, tobacco smoking, and alcohol consumption were significantly associated with VCI in these patients. By multivariate logistic regression analysis, the age, glycosylated hemoglobin, blood pressure, Hcy, and HS-CRP were revealed as independent risk factors. The age, glycosylated hemoglobin, blood pressure, Hcy, and HS-CRP can serve as predictive factors for VCI in patients with cerebral infarction.

AVP and Glu systems interact to regulate levels of anxiety in BALB/cJ mice.

Whilethe roles of glutamic acid (Glu), arginine vasopressin (AVP) and their respective receptors in anxiety have been thoroughly investigated, the effects of interactions among Glu, N-methyl-D-aspartic acid (NMDA) receptor, AVP and a-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor on anxiety are still unclear. In the present study, the agonist and antagonist of the NMDA receptor and AMPA receptor, as well as the antagonist of AVP V1 receptor (V1aR) were introduced into BALB/cJ mice by intracerebroventricular microinjection, and the anxiety-like behaviors of the mice were evaluated by open field and elevated plus-maze tests. Compared with C57BL/6 mice, BALB/cJ mice displayed higher levels of anxiety-like behavior. Significant anxiolytic effects were found in the NMDA receptor antagonist (MK-801) and the AMPA receptor or V1aR antagonist (SSRI49415), as well as combinations of AVP/MK-801 and SSRI49415/DNQX. These results indicated that anxiety-like behaviors expressed in BALB/CJ mice may be due to a coordination disorder among glutamate, NMDA receptor, AMPA receptor, AVP and V1aR, resulting in the up-regulation of the NMDA receptor and V1aR and down-regulation of the AMPA receptor. However, because the AMPA receptor can execute its anxiolytic function by suppressing AVP and V1aR, we cannot exclude the possibility of the NMDA receptor being activated by AVP acting on V1aR.

Neonatal paternal deprivation impairs social recognition and alters levels of oxytocin and estrogen receptor α mRNA expression in the MeA and NAcc, and serum oxytocin in mandarin voles.

Paternal care is necessary for the healthy development of social behavior in monogamous rodents and social recognition underpins social behavior in these animals. The effects of paternal care on the development of social recognition and underlying neuroendocrine mechanisms, especially the involvement of oxytocin and estrogen pathways, remain poorly understood. We investigated the effects of paternal deprivation (PD: father was removed from neonatal pups and mother alone raised the offspring) on social recognition in mandarin voles (Microtus mandarinus), a socially monogamous rodent. Paternal deprivation was found to inhibit the development of social recognition in female and male offspring according to a habituation-dishabituation paradigm. Paternal deprivation resulted in increased inactivity and reduced investigation during new encounters with other animals. Paternal deprivation reduced oxytocin receptor (OTR) and estrogen receptor α (ERα) mRNA expression in the medial amygdala and nucleus accumbens. Paternal deprivation reduced serum oxytocin (OT) concentration in females, but had no effect on males. Our results provide substantial evidence that paternal deprivation inhibits the development of social recognition in female and male mandarin voles and alters social behavior later in life. This is possibly the result of altered expression of central OTR and ERα and serum OT levels caused by paternal deprivation.

The effects of neonatal paternal deprivation on pair bonding, NAcc dopamine receptor mRNA expression and serum corticosterone in mandarin voles.

High levels of paternal care are important for the development of social behavior in monogamous rodents. However, the effects of paternal care on the formation of pair bonding and underlying neuroendocrine mechanisms, especially the involvements of dopamine system and corticosterone, are not well understood. We investigated effects of paternal deprivation on pair bonding in mandarin voles (Microtus mandarinus), a socially monogamous rodent. Paternal deprivation was found to inhibit the formation of pair bonding in females according to partner preference tests (PPT). Paternal deprivation also reduced body contact behavior and increased aggression in males and females in PPT. During social interaction tests (SIT), paternal deprivation was found to reduce investigative and aggressive behaviors but increase body contact and self-grooming in females, and reduce staring, aggression, body contact and self-grooming in males when interacting with the opposite sex. Paternal deprivation reduced the expression of dopamine 1-type receptor (D1R) mRNA and dopamine 2-type receptor (D2R) mRNA in the nucleus accumbens of female offspring in later life, but enhanced mRNA expression of these two dopamine receptors in males. After three days of cohabitation the expression of D1R mRNA and D2R mRNA was negatively correlated for voles reared by two parents, but positively correlated in paternally deprived animals. Paternal deprivation reduced serum corticosterone levels in females but had the opposite effect in males. Three days of cohabitation did not alter corticosterone levels of PD females, but reduced it in PC females. Our results provide substantial evidence that paternal deprivation inhibits the formation of pair bonding in female mandarin voles and alters social behavior later in life. These behavioral variations were possibly associated with sex-specific alterations in the expression of two types of dopamine receptors and serum corticosterone levels induced by paternal deprivation.

The effects of repeated early deprivation on ultrasonic vocalizations and ontogenetic development in mandarin vole pups.

Early deprivation is popularly used in rodent models as an early life social stress to investigate and determine the factors that affect the development of the brain and behavior. Ultrasonic calls made by pups play an important role in parental-pup interactions during the neonatal period. However, whether repeated early deprivation affects the properties of ultrasonic vocalizations (USVs) produced by mandarin vole (Microtus mandarinus) pups, and whether ontogenetic development is subsequently affected, remains unclear. Here we measured USVs and developmental parameters in mandarin vole pups deprived of their parents and littermates for 3h per day (ED, which is significantly different from 5 min isolation used to induce USVs) and another pup group developed under normal nest conditions (PC). Repeated measures analysis indicated that the number of USVs from ED pups was significantly lower than those from PC pups during the postnatal period (p<0.05). The pulse durations of ED pups were longer than those of PC pups at two (p<0.001) and five days of age (p<0.05), but shorter at 14 days of age (p<0.001). Compared with PC pups, the frequency range of the ED pups was wider at 18-45 kHZ, variable during the first week, smaller and narrower at 18-30 kHZ at eight and 11 days of age, and became stable similar to PC pups at 25 kHZ after 14 days of age. ED also reduced pup body weight significantly and resulted in earlier eye opening compared with PC pups (p<0.001). A positive relationship was also found between USV emissions and levels of parental care received by pups. It appears that pup USVs are an important age-dependent behavioral phenotype and an effective communicative method between parents and offspring. Prolonged parental and littermate deprivation (ED) may alter USVs emitted by pups and then ontogenetic development and parental care. Mandarin voles show USV properties similar to socially monogamous rodents and this add further support to the hypothesis that species with different social systems produce different patterns of ultrasonic vocalizations. USVs, ontogenetic development and parental care are closely associated.

Strain and sex differences in anxiety-like and social behaviors in C57BL/6J and BALB/cJ mice.

Mood disorders are more frequent in women than men, however, the majority of research has focused on male rodents as animal models. We used a variety of common behavioral tests to look for differences in anxiety-like and social behaviors between and within C57BL/6J and BALB/cJ mice. Our results show that female C57BL/6J mice exhibited lower levels of anxiety-like behavior and higher levels of activity than female BALB/cJ during the open field and elevated plus maze tests. Principal component analysis generated more factors in the behavioral variables of males than females. In the open field, a sex difference was also found and factor 1 emerged as anxiety in males, and motor activity in females. While C57BL/6J mice were found to have higher levels of social exploration and social contacts, differences were found between the sexes (females were more social) in both strains for this measure and also for anxiety-like behaviors. When interacting with animals of the same sex, levels of sniffing body and huddling in both male and female C57BL/6J mice were higher than those in male and female BALB/cJ mice. However, in the between-sex interactions, male C57BL/6J mice sniffed the stimulus mouse less, and female C57BL/6J mice sniffed the stimulus more compared to BALB/cJ mice. This study provides important behavioral phenotypes and confirms the multidimensional behavioral structure of two widely used mice strains.

Highly efficient route to functionalized tetrahydrocarbazoles using a tandem cross-metathesis/intramolecular-hydroarylation sequence.

The scope of the novel ruthenium-catalyzed tandem cross-metathesis/intramolecular-hydroarylation sequence is described. This methodology offers a practical and efficient synthesis of structurally diverse and complex tetrahydrocarbazoles in good to excellent yields (up to 98%). Moreover, preliminary efforts towards the development of an enantioselective version of the current process by sequential catalysis with ruthenium complex and chiral amine are presented, with high yields and enantioselectivities (up to 88% yield and 91% ee).

Maternal exposure to daidzein alters behaviour and oestrogen receptor alpha expression in adult female offspring.

Daidzein is an important isoflavone in soy. The potential role of daidzein in the prevention of chronic diseases is attracting growing scientific and public attention. This has led to an increase in the consumption of daidzein by humans, including adolescent and pregnant women. However, it remains unclear whether developmental exposure to daidzein affects behaviour and/or oestrogen receptor alpha (ERalpha) expression in adults. After dietary exposure to daidzein in mice during pregnancy and lactation, we observed behaviours in their female offspring during adulthood during open field, novel cage, elevated plus-maze, Morris water maze and social interaction tests. Central ERalpha expression was also examined using immunocytochemistry. Compared with a control group, female mice exposed to daidzein during early development through their mother showed significantly more affiliation behaviours when they encountered female stimuli. The acquisition and retrieval of spatial memory in the water maze test were also significantly improved by exposure to daidzein. Finally, females exposed to daidzein showed significantly less ERalpha expression in bed nucleus of the stria terminalis and medial amygdala. In combination, our findings show that maternal exposure to daidzein has a masculinisation effect on memory and social behaviour, suggesting a potential role of ERalpha distribution in the brains of female mice when regulating these behaviours.

Rational combination of two privileged chiral backbones: highly efficient organocatalysts for asymmetric direct aldol reactions between aromatic aldehydes and acylic ketones.

A new class of organocatalysts has been designed by rational combination of proline with cinchona alkaloids. The chiral amine 3a, prepared from l-proline and cinchonidine, has been found to be an efficient catalyst for the direct aldol reactions of acetone or 2-butanone with a wide range of aldehydes (up to 98% ee). The cinchonidine backbone is essential to the reaction efficiency and enantioselectivity.