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Poly (lactic acid) (PLA) has been proposed as a promising orthopedic implant material, whereas insufficient mechanical strength, unsatisfied biocompatibility and inappropriate degradation rate restrict its further application. In this work, self-reinforced poly (lactic acid)-b-poly(lactide-co-caprolactone) (PLA-b-PLCL) block copolymer with long-chain branches was fabricated through two-stage orientation. Compared with smooth and hydrophobic PLA surface, the surface of PLA-b-PLCL presented micro-phase separated structure with improved hydrophilicity, and cells seeded on it showed improved adhesion/proliferation and high alkaline phosphatase (ALP) activity. After the 1st stage orientation at temperature higher than Tsubg1/sub(glass transition temperature of PLA phase), the amount of CHsub3/suband CO groups on surface of PLA-b-PLCL increased, while "groove-ridge" structure formed, resulting in enhancement of surface hydrophobicity. After the 2nd stage orientation at Tsubg1/sub ~ Tsubg2/sub(glass transition temperature of PLCL phase), surface hydrophobicity/amount of CO groups further increased and "groove-ridge" structure became more significant. Due to suitable wettability and enhanced material-cell mechanical interlocking, cell proliferation/ALP activity were improved and a continuous cell layer formed on sample surface. During in vitro degradation in phosphate buffered saline solution, by introduction of PLCL segments, the crystallinity decreased and solution absorption increased, resulting in a rapid deterioration of mechanical properties. After the 1st stage orientation, a dense microfibrillar structure with high crystallinity formed, which hindered diffusion of solution and delay hydrolytic degradation. After the 2nd stage orientation, PLCL segments were arranged more closely, resulting in a further inhibition of degradation, which was helpful for controlling the strength decay rate of PLA as bone fixation materials.

The formation of the 2D Bi4Ti3O12–BiVO4–Bi4V2O10 heterostructure and the piezoelectric effect on photoredox activity improvements.

As a visible-light response photocatalyst, BiVO4 is widely used in photocatalytic oxygen evolution. In this study, a novel BiVO4−Bi6O6(OH)3(NO3)3 (BBN) heterostructure fabricates via a simple one-pot hydrothermal approach is certified to effectively restrain the recombination of carriers by efficient spatial charge separation. By employing BBN as a reductive-function photocatalyst, a solid-state Z-scheme is constructed to improve the photo-redox capacity of BiVO4 and hydrogen production is realized in the BiVO4−BBN heterostructure for the first time. The solid-state Z-scheme introduced in the BiVO4−BBN ensures the photoexcited carriers with the powerful redox capacity to participate in the photocatalytic reaction.

Graphitic carbon nitride (g-C3N4) possesses fascinating merits, but its practical applications are limited by the inferior properties of limited visible-light sorption, rapid recombination of photo-excited charge carriers and low electrical conductivity. Introduction of N-defects is an efficient approach to tune its optical properties, but strategies capable of creating abundant vacancies and simultaneously maintaining the highly crystalline architecture are still limited and highly desired. In this work, a facile construction methodology was demonstrated to afford g-C3N4 with abundant N vacancies, high crystallinity, a hydrophilic surface structure, a small particle size, and an increased surface area under neat and mild conditions. The essence of our approach lies in the treatment of the bulk g-C3N4 precursor with an alkaline salt (LiN(SiMe3)2) with a low melting point, moderate nucleophilicity, and easy removal procedures. The unique structural properties of the afforded ND-g-C3N4 allow for a significantly redshifted absorption edge and enhanced charge carrier separation, leading to superior photocatalytic hydrogen evolution performance three times that obtained by pristine g-C3N4. The modification strategy developed herein sheds light on the fabrication of g-C3N4-based materials with improved photocatalytic efficiency via efficient introduction of N defects, variation of the surface structure, and retention of the high crystallinity.

Cryptosporidium spp. and Enterocytozoon bieneusi are two well-known protist pathogens which can result in diarrhea in humans and animals. To examine the occurrence and genetic characteristics of Cryptosporidium spp. and E. bieneusi in pet red squirrels (Sciurus vulgaris), 314 fecal specimens were collected from red squirrels from four pet shops and owners in Sichuan province, China. Cryptosporidium spp. and E. bieneusi were examined by nested PCR targeting the partial small subunit rRNA (SSU rRNA) gene and the ribosomal internal transcribed spacer (ITS) gene respectively. The infection rates were 8.6% (27/314) for Cryptosporidium spp. and 19.4% (61/314) for E. bieneusi. Five Cryptosporidium species/genotypes were identified by DNA sequence analysis: Cryptosporidium rat genotype II (n = 8), Cryptosporidium ferret genotype (n = 8), Cryptosporidium chipmunk genotype III (n = 5), Cryptosporidium rat genotype I (n = 4), and Cryptosporidium parvum (n = 2). Additionally, a total of five E. bieneusi genotypes were revealed, including three known genotypes (D, SCC-2, and SCC-3) and two novel genotypes (RS01 and RS02). Phylogenetic analysis revealed that genotype D fell into group 1, whereas the remaining genotypes clustered into group 10. To our knowledge, this is the first study to report Cryptosporidium spp. and E. bieneusi in pet red squirrels in China. Moreover, C. parvum and genotype D of E. bieneusi, previously identified in humans, were also found in red squirrels, suggesting that red squirrels may give rise to cryptosporidiosis and microsporidiosis in humans through zoonotic transmissions. These results provide preliminary reference data for monitoring Cryptosporidium spp. and E. bieneusi infections in pet red squirrels and humans.

Enterocytozoon bieneusi, a unicellular enteric microsporidian parasite, can infect humans and a wide range of animals throughout the world. Although E. bieneusi has been identified in many animals, there is no information regarding the genotypes of E. bieneusi in pet birds in China. Birds are important sources of emerging infectious diseases that affect humans, and immunosuppressed individuals can be exposed to potential zoonotic agents shed by birds. The aim of the present study was to determine the prevalence and genotypic diversity of E. bieneusi in pet birds, as well as assessed its zoonotic potential. A total of 387 fecal samples were collected from Psittaciformes (n = 295), Passeriformes (n = 67), and Galliformes (n = 16) from four pet markets in Sichuan province, Southwestern China. The overall prevalence of E. bieneusi in pet birds was 25.1% based on nested polymerase chain reaction analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene (Psittaciformes, 21.7%; Passeriformes, 37.3%; Galliformes, 50.0%). Eight genotypes of E. bieneusi were identified, including five known genotypes (D, SC02, BEB6, CHB1, and MJ5) and three novel genotypes (SCB-I, SCB-II, and SCB-III). In phylogenetic analysis, genotypes D and SC02 and one novel genotype SCB-II were clustered within group 1, genotype BEB6 was classified within group 2, and the remaining genotypes (CHB1, MJ5, SCB-I, and SCB-III) clustered with group 10. To the best of our knowledge, this is the first report of E. bieneusi infection in pet birds in China. Genotypes D, SC02, and BEB6 that have been previously identified in humans, were found in pet birds in this study, suggesting that these pet birds can be a potential source of human microsporidiosis in China. Keywords: Enterocytozoon bieneusi, ITS, Pet bird, Zoonotic potential, China

Blastocystis is a common enteric protist that colonizes humans and a wide range of animals. Although some studies have reported incidences of Blastocystis in humans and animals in China, there is no information available on the prevalence of Blastocystis in giant pandas, red pandas, or bird species. The aims of the present study were to determine the prevalence, subtype distribution, and genetic characterizations of Blastocystis in these animals in a captive situation in southwestern China, as well as assess the zoonotic potential of Blastocystis isolates. A total of 168 fecal specimens, including 81 from giant pandas, 23 from red pandas, 38 from black swans, 11 from ruddy shelducks, and 15 from green peafowl were collected at the Chengdu Research Base of Giant Panda Breeding in Sichuan province. The overall minimum prevalence of Blastocystis was 11.3% (19/168) based on PCR amplification of the barcode region of the SSU rRNA gene. The highest prevalence of Blastocystis was observed in ruddy shelduck (18.2%) and the lowest was found in green peafowl (6.7%). The prevalence of Blastocystis in giant pandas >5.5 years of age was higher than that in younger giant pandas. Two potentially zoonotic subtypes (ST1 and ST8) were identified, and ST1 (n = 12) was found to be more prevalent than ST8 (n = 7). To the best of our knowledge, this is the first report of the prevalence and subtypes of Blastocystis in giant pandas, red pandas, and bird species in China. The findings of this study will improve our understanding of the genetic diversity and public health potential of Blastocystis. Keywords: Blastocystis, Pandas, Genetic diversity, Zoonotic potential, China

The effects of atmosphere conditions on microstructural and mechanical properties of stainless steel 17-4PH components fabricated by laser direct manufacturing (LDM) were investigated through measurements on phase constitution, porosity, tensile strength, fracture morphology, hardness and evolution of substrate temperature. Results showed that the samples produced in air atmosphere condition possessed higher tensile strength and hardness for both as-deposited and heat-treated states than that in Ar chamber condition, due to dispersion strengthening effect of amorphous oxide particles and nitrogen solution strengthening as a result of higher content of oxygen and nitrogen. The temperature of substrate heat accumulation was higher in Ar chamber condition, leading to dramatically lower porosity and more reverse austenite, which also contributed to the lower strength and hardness.

Background Microsporidia are common opportunistic parasites in humans and animals, including rabbits. However, only limited epidemiology data concern about the prevalence and molecular characterization of Enterocytozoon bieneusi and Encephalitozoon spp. in rabbits. This study is the first detection and genotyping of Microsporidia in pet rabbits in China. Results A total of 584 faecal specimens were collected from rabbits in pet shops from four cities in Sichuan province, China. The overall prevalence of microsporidia infection was 24.8% by nested PCR targeting the internal transcribed spacer (ITS) region of E. bieneusi and Encephalitozoon spp. respectively. E. bieneusi was the most common species (n = 90, 15.4%), followed by Encephalitozoon cuniculi (n = 34, 5.8%) and Encephalitozoon intestinalis (n = 16, 2.7%). Mixed infections (E. bieneusi and E. cuniculi) were detected in five another rabbits (0.9%). Statistically significant differences in the prevalence of microsporidia were observed among different cities (χ2 = 38.376, df = 3, P 2 = 9.018, df = 2, P E. bieneusi were obtained, including five known (SC02, I, N, J, CHY1) and six novel genotypes (SCR01, SCR02, SCR04 to SCR07). SC02 was the most prevalent genotype in all tested cities (43.3%, 39/90). Phylogenetic analysis showed that these genotypes were clustered into group 1–3 and group 10. Meanwhile, two genotypes (I and II) were identified by sequence analysis of the ITS region of E. cuniculi. Conclusion To the best of our knowledge, this is the first report of microsporidia infection in pet rabbits in China. Genotype SC02 and four novel genotypes were classified into potential zoonotic group 1, suggesting that pet rabbits may cause microsporidiosis in humans through zoonotic transmissions. These findings provide preliminary reference data for monitoring microsporidia infections in pet rabbits and humans.

LysR-type transcriptional regulators are involved in the regulation of numerous cellular metabolic processes in Klebsiella pneumoniae, leading to severe infection. Earlier, we found a novel LysR family gene, named kp05372, in a strain of K. pneumoniae (designated GPKP) isolated from forest musk deer. To study the function of this gene in relation to the biological characteristics of GPKP, we used the suicide plasmid and conjugative transfer methods to construct deletion mutant strain GPKP-Δkp05372; moreover, we also constructed the GPKP-Δkp05372 (+) complemented strain. The role of this gene was determined by comparing the following characteristics of three strains: growth curves, biofilm formation, drug resistance, stress resistance, median lethal dose (LD(50)), organ colonization ability, and the histopathology of GPKP. Real-time polymerase chain reaction (RT-PCR) was used to test the expression level of seven genes upstream of kp05372. There was no significant difference in the growth rates when comparing the three bacterial strains, and no significant difference was recorded at different osmotic pressures, temperatures, salt contents, or hydrogen peroxide concentrations. The GPKP-Δkp05372 mutant formed a weak biofilm, and the other two strains formed medium biofilm. The drug resistance of the GPKP-Δkp05372 mutant toward cephalothin, cotrimoxazole, and polymyxin B was changed. The acid tolerance of the deletion strain was stronger than that of the other two strains. The LD(50) values of the wild-type and complemented strains were 174-fold and 77-fold higher than that of the GPKP-Δkp05372 mutant, respectively. The colonization ability of the GPKP-Δkp05372 mutant in the heart, liver, spleen, kidney, and intestine was the weakest. The three strains caused different histopathological changes in the liver and lungs. In the GPKP-Δkp05372 mutant, the relative expression levels of kp05374 and kp05379 were increased to 1.32-fold and 1.42-fold, respectively, while the level of kp05378 was decreased by 42%. Overall, the deletion of kp05372 gene leads to changes in the following: drug resistance and acid tolerance; decreases in virulence, biofilm formation, and colonization ability of GPKP; and regulation of the upstream region of adjacent genes.

BiVO4 is widely used in photodegradation and photocatalytic oxygen evolution under visible-light irradiation. In this study, to reduce the recombination rate of photoexcited electrons and holes and...

ZnO sheets with short carrier transport distance are suitable for constructing heterostructures for improved photocatalytic hydrogen evolution activity. Narrow bandgap CdSe nanoparticles (NPs) can be used to sensitize the ZnO sheets and consequently extend the visible light response range. The ZnO-CdSe heterostructural sheets, synthesized through a light-assisted growth method, consisted of single-crystal ZnO sheets and CdSe NPs distributed on the surface of ZnO sheets. The ZnO-CdSe heterostructural sheets exhibited higher photocatalytic hydrogen rate than ZnO, CdSe, and ZnO particle-CdSe under light irradiation. The photocatalytic hydrogen evolution rates of the ZnO-CdSe heterostructural sheets were significantly improved under UV–visible and visible light (λ ≥ 420 nm) irradiations when Pt nanoparticles were loaded as cocatalysts. The heterostructural sheets also exhibited stable hydrogen generation rate in a long-term photocatalytic reaction. The synergistic effect between ZnO sheets and CdSe NPs and shortened transport distance of photoexcited carriers in the sheet-like heterostructure mainly contributed to the improved photocatalytic hydrogen activity.

BiVO4 is widely used for photoelectrochemistry and photocatalytic oxygen evolution under visible-light irradiation. To extend the range of visible-light absorption and reduce the recombination rate of photoexcited electrons and holes, a BiVO4 sheet–Bi2S3 nanowire heterostructure was fabricated through an easy in situ hydrothermal method. In this method, Bi2S3 nanowires were uniformly coated onto the surface of BiVO4 sheets. The heterostructure exhibits a wide visible-light absorption band ranging from 525 to 900 nm after coupling with Bi2S3 nanowires. The BiVO4 sheet–Bi2S3 nanowire heterostructures were used for photoelectrochemical measurements and exhibited higher photocurrent intensity than those of BiVO4 sheets and BiVO4 particle–Bi2S3 under visible-light irradiation. The optimized amount of Bi2S3 in the heterostructure was approximately 2.4 at. %. The remarkable enhancements in the photoelectrochemical property were attributed mainly to the solid sensitization of Bi2S3 nanowires providing a number of...

ZnO is a semiconductor photocatalyst widely applied in photodegradation of organic pollutants and in photoelectric conversion. ZnO exhibits low photocatalytic activity due to poor absorption in the visible region. In this work, a novel cobalt-induced electrochemical growth method was developed to synthesize cobalt-doped ZnO/rGO nanoparticles in an aqueous solution at room temperature. Cobalt-doped ZnO/rGO nanoparticles exhibited wider visible-light absorption band ranging from 400 nm to 700 nm due to cobalt doping. The surface structure of ZnO formed by the cobalt-induced electrochemical method without other ions is suitable for photocatalytic reactions. The cobalt-doped ZnO/rGO nanoparticles were found to exhibit in photodegradation and photo-electrochemical measurements and exhibited enhanced photocatalytic activity under visible-light irradiation.

Photocatalytic hydrogen evolution over semiconductors is an efficient method for solar-energy conversion. Heterostructural photocatalysts with separated photoexcited carriers exhibit efficient photocatalytic hydrogen evolution without co-catalysts. In this study, heterostructures comprising of Cd 1-x Zn x S and Zn 1-y Cd y S phases were prepared through the replacement and sulfuration process at high temperature using Zn powders as the precursor. Highly crystalline Cd 1-x Zn x S-Zn 1-y Cd y S heterostructures without noble metal co-catalysts present a stable and highly effective photocatalytic hydrogen evolution rate under both UV–visible and visible-light irradiations due to the synergistic effects of Cd 1-x Zn x S and Zn 1-y Cd y S.

Pneumonia is one of the major diseases of forest musk deer (FMD) that affects the survival of musk deer breeding farms. Lung pathogenic Escherichia coli (LPEC) strains were found to be one of the principal bacterial pathogens, and O78 was found to be the dominant serotype and the most poisonous, thus it was selected as further study. Here we have finished the LPEC O78 genome sequence, genomic comparative analysis and genome annotation. In the genome of LPEC O78, genes encoded major virulence factors (VFs) of urinary tract infection (UTI) and neonatal meningitis-causing E. coli (NMEC) were detected. The phylogenetic analysis indicated that LPEC O78 belongs to the D group of E. coli and clustered with human uropathogenic E. coli (UPEC) UMNO26. Orthologous analysis showed that LPEC O78 was close to UMNO26 in evolutionary relationships, the results were consistent with phylogenetic analysis. Additionally, analysis of the specific genes using COG, GO and Swiss-Prot databases revealed specific functions in the LPEC O78, some of these differences might reflect the pathogenicity of LPEC O78. It was the first time that LPEC from FMD was sequenced, through the virulence gene analysis, an example of a genome of chimeric pathogenic properties was found. The results were in favor of the possibility that strain of animal origin LPEC O78 was dangerous for public health and consequently constitute a zoonotic risk. Moreover, the functions study of specific genes will facilitate understand the pathogenicity of LPEC O78, and aid in the development of control measures.

A total of 333 fecal specimens from horses in southwestern China were genotyped based on analysis of the small subunit rRNA (SSU rRNA) gene. Cryptosporidium hominis and Cryptosporidium andersoni were identified in 2 and 4 stool specimens, respectively. The identification of C. hominis was confirmed by sequence analysis of the 70‐kDa heat shock protein (HSP70) and oocyst wall protein (COWP) genes. Subtyping analysis of the 60‐kDa glycoprotein (GP60) gene sequence of C. hominis revealed a new rare subtype Id, named IdA15; only three Id isolates have been reported in humans to date. Multilocus sequence typing (MLST) analysis indicated that the C. andersoni subtype was A6, A5, A2, and A1 at the four minisatellite loci (MS1, MS2, MS3, and MS16, respectively). This is the first report to identify the presence of C. andersoni and C. hominis in horses in southwestern China and the first to identify a rare zoonotic subtype Id of C. hominis in horses. These findings suggest that infected horses may act as potential reservoirs of Cryptosporidium to transmit infections to humans.

Additional file 1: Table S1. Primer sequences, fragment lengths and annealing temperatures used in this study.

Additional file 2: Figure S1. Sequence variation in the ITS region of the rRNA gene of Enterocytozoon bieneusi isolates from pet rabbits. The ITS sequences of five known genotypes (SC02, I, N, J, and CHY1) and the six novel genotypes (SCR01, SCR02, SCR04 to SCR07), identified in this study, were aligned with each other.

Probiotics are intended to provide health benefits when consumed, generally by improving or restoring the gut flora. The health problems of forest musk deer (FMD, Moschus berezovskii), a threatened species currently under conservation, restrict the development of captive musk deer. This study was conducted with the aim of analyzing the effects of forest musk deer compound probiotics (FMDPs) on weight, immunity performance and fecal microbiota in FMD by measuring average daily weight gain (ADG) and immune-related factors and by using high-throughput 16S rRNA sequencing to investigate differences in the fecal microbiota among the control group (4 samples), treatment group A (4 samples) and treatment group B (4 samples). The results showed that the ADG of treatment groups A and B was significantly higher than that of the control group (p = 0.032, p = 0.018). The increase in IgA and IgG levels in treatment group B was significantly higher than that in the control group (p = 0.02, p = 0.011). At the phylum and genus levels, the difference in bacterial community structure was significant between treatment group B and the control group. Both the alpha diversity and beta diversity results showed significant differences in the microbiota of FMD before and after FMDP feeding. In summary, the results indicated that FMDPs could promote the growth of growing FMD, improve immunity and balance the role of intestinal microbes.

Klebsiella pneumoniae is an important pathogen commonly associated with opportunistic infections. In this study, lung pathogenic K. pneumoniae (LPKP) was isolated and identified from suppurative pneumoniae in forest musk deer by conventional methods and by 16S ribosomal RNA sequence analysis. Median lethal dose and histopathologic analysis were used to demonstrate pathogenicity of the organism in mice. Furthermore, a draft genome of LPKP was sequenced, and its virulence genes were detected. One hundred and twenty-two virulence genes encoded determinant of capsule polysaccharide (CPS), lipopolysaccharide, fimbriae, outer membrane proteins, iron acquisition, and urease. In particular, 20 CPS-related genes were highly conserved in LPKP, K. pneumoniae U, K. pneumoniae NTUH-KP35, and K. pneumoniae KP-1. All of the strains were identified as capsular type K54. This is the first report of capsular type K54 K. pneumoniae causing suppurative pneumonia in an animal. The results of this study provided the basis for understanding the pathogenicity of LPKP and laid a foundation for the development of vaccines for the capsular type K54 K. pneumoniae disease.

Giardia intestinalis, a cosmopolitan zoonotic parasite, is one of the most common causes of protozoal diarrhea in both humans and animals worldwide. Although G. intestinalis has been detected in many animals, information regarding its prevalence and genotype in Chinese racehorses is scarce. In the present study, we investigated the prevalence of G. intestinalis in racehorses and performed molecular characterization of the pathogen to assess its zoonotic potential. Two hundred and sixty-four racehorse fecal samples from six equestrian clubs located in different regions of the Sichuan province of southwestern China were examined. Nested polymerase chain reaction (PCR) analysis of the gene encoding triose-phosphate isomerase (tpi) showed the prevalence of G. intestinalis to be 8.3% (22/264), and the prevalence in different clubs varied from 3.6% to 13.5%. Three assemblages were identified in the successfully sequenced samples, including the potentially zoonotic assemblages A (n = 5) and B (n = 14), the mouse-specific assemblage G (n = 3), and a mixed A and B assemblage. Sequence analysis of tpi, glutamate dehydrogenase (gdh), and beta giardin (bg) loci revealed that the majority of sequences isolated from assemblage A were identical to the subtype AIV and assemblage B isolates showed variability among the nucleotide sequences of the subtype BIV. Using the nomenclature for the multilocus genotype (MLG) model, one each of multilocus genotypes A (MLG1) and B (MLG2) were identified, with MLG2 being a novel genotype. To the best of our knowledge, this is the first study to investigate G. intestinalis in Chinese racehorses. The presence of both animal and human assemblages of G. intestinalis in racehorses indicated that these animals might constitute a potential zoonotic risk to human beings.

Hexagonal prism-like ZnO crystals dominated with polar facets were synthesized using a hydrothermal method. The Gold (Au) nanoparticles were selectively photodeposited on the polar surfaces of faceted ZnO crystals as a result of anisotropic photocatalytic activities of the polar and nonpolar facets. The size of Au nanoparticles uniformly dispersed on the polar facets increased with increasing Au-loading amount. These Au-loaded ZnO crystals showed an additional visible light absorption band from 400nm to 800nm. The 0.1wt% Au-loaded ZnO crystals with visible light absorption peak at approximately 690nm exhibited the highest photocatalytic activity under visible light irradiation.