[Metagenomic next-generation sequencing for the diagnosis of Pneumocystis jirovecii pneumonia after allogeneic hematopoietic stem cell transplantation]

Objectives: To investigate the value of metagenomic next-generation sequencing (mNGS) in the diagnosis of Pneumocystis jirovecii pneumonia (PJP) in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: The data of 98 patients with suspected pulmonary infection after allo-HSCT who underwent pathogen detection from bronchoalveolar lavage fluid between June 2016 and August 2023 at Nanfang Hospital were analyzed. The diagnostic performance of mNGS, conventional methods, and real-time quantitative polymerase chain reaction (qPCR) for PJP were compared. Results: A total of 12 patients were diagnosed with PJP, including 11 with a proven diagnosis and 1 with a probable diagnosis. Among the patients with a proven diagnosis, 1 was positive by both conventional methods and qPCR, and 10 were positive by qPCR only. Pneumocystis jirovecii was detected by mNGS in all 12 patients. The diagnostic sensitivity of mNGS for PJP was 100%, which was greater than that of conventional methods (8.3%, P=0.001) and similar to that of qPCR (91.6%, P=1.000) . A total of 75% of the patients developed mixed pulmonary infections, and cytomegalovirus and Epstein-Barr virus were the most common pathogens. Mixed infection was detected in eight patients by mNGS and in five patients by qPCR, but not by conventional methods (P=0.008) . Conclusions: mNGS had good sensitivity for diagnosing PJP after allo-HSCT and was advantageous for detecting mixed infectious pathogens; therefore, mNGS might be an effective supplement to regular detection methods and qPCR.

[Analysis of factors associated with proximal junctional kyphosis after surgery for Lenke type 5 adolescent idiopathic scoliosis]

Objective: To investigate the risk factors associated with the development of proximal junctional kyphosis (PJK) after posterior spinal fusion for in children with Lenke type 5 adolescent idiopathic scoliosis (AIS). Methods: It was a retrospective case-control study that included medical records of 98 children with Lenke type 5 AIS who underwent posterior orthopedic surgery under general anesthesia at the Honghui Hospital Affiliated to Xi'an Jiaotong University from January 2013 to December 2018. There were 23 males and 75 females with a mean age of (14.5±2.2) years (10-18 years). Patients were divided into PJK and non-PJK groups according to whether the posterior junctional angle (PJA) was greater than 10° and increased for more than 10° from the preoperative period at the the last follow-up. Univariate analysis was used to analyze the correlation of general data of the children with occurrence of PJK after the operation. Multivariate logistic regression analysis was used to analyze the risk factors of postoperative PJK. Results: There were 35 cases in the PJK group and 63 cases in the non-PJK group. The PJK and non-PJK groups were followed up for (35.6±7.3) months and (36.4±7.5) months, respectively, and the difference was not statistically significant (P=0.637). There was no statistically significant difference between the two groups in general data such as gender, age, and body mass index (all P>0.05), while there were statistically significant differences between the two groups in upper instrumented vertebrea (UIV) location and junctional area posterior ligamentous complex (PLC) injury (all P<0.05). The results of univariate analysis showed that UIV location at T10-T12, junctional area PLC injury, preoperative coronal thoracic curve (TC), preoperative and final follow-up PJA, and preoperative and final follow-up pelvic incidence-lumbarlordosis (PI-LL) were correlated with postoperative PJK (OR=2.50, 5.37, 0.92, 1.12, 1.32, 1.06, 3.35, all P<0.05). Multifactorial logistic regression analysis showed that UIV located at T10-T12 (OR=2.346, 95%CI: 1.582-3.481, P=0.001), junctional area PLC injury (OR=5.112, 95%CI: 1.283-20.418, P=0.023) and last follow-up PI-LL (OR=1.826, 95%CI: 1.558-24.745, P=0.012) were risk factors for the occurrence of postoperative PJK in children with Lenke type 5 AIS. Conclusions: Postoperative UIV fixation to the thoracolumbar segment, PLC injury in the junctional area and excessive postoperative PI-LL in children with Lenke type 5 AIS may be the risk factors for the occurrence of PJK after the operation. It is suggested that avoidance of UIV selection to the thoracolumbar segment, intraoperative protection of the PLC located near the UIV and restoration of a good PI-LL relationship may reduce the incidence of PJK.

Optimal water supply reservoir operation by leveraging the meta-heuristic Harris Hawks algorithms and opposite based learning technique

To ease water scarcity, dynamic programming, stochastic dynamic programming, and heuristic algorithms have been applied to solve problem matters related to water resources. Development, operation, and management are vital in a reservoir operating policy, especially when the reservoir serves a complex objective. In this study, an attempt via metaheuristic algorithms, namely the Harris Hawks Optimisation (HHO) Algorithm and the Opposite Based Learning of HHO (OBL-HHO) are made to minimise the water deficit as well as mitigate floods at downstream of the Klang Gate Dam (KGD). Due to trade-offs between water supply and flood management, the HHO and OBL-HHO models have configurable thresholds to optimise the KGD reservoir operation. To determine the efficacy of the HHO and OBL-HHO in reservoir optimisation, reliability, vulnerability, and resilience are risk measures evaluated. If inflow categories are omitted, the OBL-HHO meets 71.49% of demand compared to 54.83% for the standalone HHO. The HHO proved superior to OBL-HHO in satisfying demand during medium inflows, achieving 38.60% compared to 20.61%, even though the HHO may have experienced water loss at the end of the storage level. The HHO is still a promising method, as proven by its reliability and resilience indices compared to other published heuristic algorithms: at 62.50% and 1.56, respectively. The Artificial Bee Colony (ABC) outcomes satisfied demand at 61.36%, 59.47% with the Particle Swarm Optimisation (PSO), 55.68% with the real-coded Genetic Algorithm (GA), and 23.5 percent with the binary GA. For resilience, the ABC scored 0.16, PSO scored 0.15, and real coded GA scored 0.14 whilst the binary-GA has the worst failure recovery algorithm with 0.09.

Escherichia coli inhibits endometriosis by inducing M1 polarity of peritoneal macrophages and the IL-1 signaling pathway

The development of endometriosis is closely linked to macrophages, and the type M1 macrophage has been hypothesized to play an inhibitory role in its progression. Escherichia coli induces macrophage polarization toward M1 in numerous diseases and differs in the reproductive tract of patients with and without endometriosis; however, its specific role in endometriosis development remains unknown. Therefore, in this study, E. coli was selected as a stimulator to induce macrophages, and its effects on the growth of endometriosis lesions in vitro and in vivo were investigated using C57BL/6N female mice and endometrial cells. It was revealed that E. coli inhibited the migration and proliferation of co-cultured endometrial cells by IL-1 in vitro and prevented the growth of lesions and induced macrophage polarization toward M1 in vivo. However, this change was counteracted by C-C motif chemokine receptor 2 inhibitors, suggesting that it was associated with bone marrow-derived macrophages. Overall, the presence of E. coli in the abdominal cavity may be a protective factor for endometriosis.

[A multicenter clinical trial of collar-button type keratoprosthesis implantation for the treatment of corneal blindness in high-risk transplantation]

Objective: To evaluate the efficiency and safety of collar-button type keratoprosthesis (c-bKPro) implantation for corneal blindness in high-risk transplantation in China. Methods: It was a case series study. High-risk corneal blind patients who planned to undergo c-bKPro implantation were prospectively and continuously enrolled in the Eye Hospital of Shandong First Medical University, Ophthalmology Division of Chinese PLA General Hospital, Zhongshan Ophthalmic Center, Department of Ophthalmology in Eye & ENT Hospital of Fudan University, and Eye Hospital of Wenzhou Medical University from July 2019 to January 2020. The cure for blindness and surgical success were assessed based on visual acuity (VA)≥0.05. The complications and keratoprosthesis retention rate were recorded to determine the safety of the surgery. Results: Thirty-seven subjects (eyes) were included, of which 32 were male and 5 were female, aged 27 to 72 years old. The indications of c-bKPro implantation were corneal graft failure (21 eyes, 56.8%), chemical injury (8 eyes, 21.6%), thermal burn (5 eyes, 13.5%), unexplained corneal opacity (2 eyes, 5.4%), and corneal perforation (1 eye, 2.7%). Two patients withdrew from the clinical trial at 3 months postoperatively. Thirty-five patients were followed up for 6 months, and 31 were followed up for 12 months. The VA was ≥0.05 in 83.8% of eyes at 6 months and in 81.8% of eyes at 12 months. Among the 11 eyes diagnosed with concurrent glaucoma, 6 eyes achieved a VA of ≥0.05. At 12 months, the c-bKPro retention rate was 100%. The surgical complications included retroprosthetic membrane formation (5 eyes, 16.1%), persistent corneal epithelial defects (5 eyes, 16.1%), macular edema (4 eyes, 12.9%), new-onset glaucoma (4 eyes, 12.5%; including one eye withdrawn from the study at 3 months), sterile corneal melting (2 eyes, 6.5%), sterile vitritis (1 eye, 3.2%), and infectious keratitis (1 eye, 3.2%). Conclusions: C-bKPro implantation is an effective and safe option for treating corneal blindness in high-risk transplantation in China. Improved visual outcomes could be achieved in most cases, with a relatively low incidence of postoperative complications.

A 1.1 Mb duplication CNV on chromosome 17 contributes to skeletal muscle development in Boer goats

The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance. However, the genetic basis of muscle development in the Boer goat remains obscure. In this study, we identified specific structural variants in the Boer goat based on genome-wide selection signals and analyzed the basis of the molecular heredity of related candidate genes in muscle development. A total of 9 959 autosomal copy number variations (CNVs) were identified through selection signal analysis in 127 goat genomes. Specifically, we confirmed that the highest signal CNV (HSV) was a chromosomal arrangement containing an approximately 1.11 Mb (CHIR17: 60062304-61171840 bp) duplicated fragment inserted in reverse orientation and a 5 362 bp deleted region (CHIR17:60145940-60151302 bp) with overlapping genes (e.g., ARHGAP10, NR3C2, EDNRA, PRMT9, and TMEM184C). The homozygous duplicated HSV genotype (+/+) was found in 96% of Boer goats but was not detected in Eurasian goats and was only detected in 4% of indigenous African goats. The expression network of three candidate genes ( ARHGAP10, NR3C2, and EDNRA) regulating dose transcription was constructed by RNA sequencing. Results indicated that these genes were involved in the proliferation and differentiation of skeletal muscle satellite cells (SMSCs) and their overexpression significantly increased the expression of SAA3. The HSV of the Boer goat contributed to superior skeletal muscle growth via the dose effects of overlapping genes.

Comparative analysis of the genetic diversity of the neutral microsatellite loci and second exon of the goat MHC-DQB1 gene

This study compared and analyzed the genetic diversity and population structure of exon 2 of the DQB1 gene and 13 autosomal neutral microsatellite markers from 14 Chinese goat breeds to explore the potential evolutionary mechanism of the major histocompatibility complex (MHC). A total of 287 haplotypes were constructed from MHC-DQB1 exon 2 from 14 populations, and 82 nucleotide polymorphic sites (SNPs, 31.78%) and 172 heterozygous individuals (79.12%) were identified. The F_ST values of the microsatellites and MHC-DQB ranged between 0.01831-0.26907 and 0.00892-0.38871, respectively. Furthermore, 14 goat populations showed rich genetic diversity in the microsatellite loci and MHC-DQB1 exon 2. However, the population structure and phylogenetic relationship represented by the two markers were different. Positive selection and Tajima's D test results showed the occurrence of a diversified selection mechanism, which was primarily based on a positive and balancing selection in goat DQB. This study also found that the DQB sequences of bovines exhibited trans-species polymorphism (TSP) among species and families. In brief, this study indicated that positive and balancing selection played a major role in maintaining the genetic diversity of DQB, and TSP of MHC in bovines was common, which enhanced the understanding of the MHC evolution.

[A case of ocular siderosis caused by iron ore]

A patient complained of vision loss of his left eye which was crushed by iron ore for 11 months. The cornea of the injured eye was thin and swollen, and a large amount of rust-like material was observed to be deposited. An intraocular foreign body was found by orbital CT. During vitrectomy, a piece of metal sheet was found near the ora serrate, and the intraocular structure was severely damaged, and characterized by vitreous brown turbidity, a white optic disc, occlusion of blood vessels in the fundus, and peripheral retinal atrophy with degeneration. The patient was diagnosed as ocular siderosis in the left eye.

[The prevention and therapy of corneal ulcers in patients with large-area thermal burns]

Objective: To evaluate the characteristics of ocular injury in patients with severe extensive thermal burns, and to explore the effective methods to prevent and treat corneal ulcers related to severe burns. Methods: A retrospective case series study. Between 2010 and 2019, Sixteen severe thermal burn patients with burn sizes>70% of the total body surface area involving the ocular region were admitted to the Burns and Plastic Surgery Division of Chinese PLA General Hospital, and consult with Ophthalmology Division. There were deep second-degree to fourth-degree burns in the eyelids. In the eleven surviving patients, 22 eyes presented ectropion. Eyelid full-thickness skin grafting (EFTSG) combined with or without tarsorrhaphy was performed in 20 eyes due to severe corneal exposure. Two eyes received partial blepharorrhaphy because of mild ectropion. The ocular manifestations and treatment outcomes were reviewed and assessed. Results: The majority of the patients were youth, and the average age was (36.8±10.4) years. The burn area was 84.0%±9.1% of the body surface area. Corneal ulcers secondary to lagophthalmos occurred at (35.1±15.6) days after burning in 75% (24/32) of eyes. Perforation was found in 18.8% (6/32) of eyes. Among the 22 operated eyes, the corneal ulcer was repaired in all 9 eyes receiving EFTSG with tarsorrhaphy, whereas ectropion recurred in 8 of 11 eyes only receiving EFTSG, and 4 eyes underwent further surgery due to corneal epithelial defects. Conclusions: In patients with severe large-area thermal burns, corneal ulcers are common complications. Prevention of corneal exposure is vital because the treatment of corneal ulceration is difficult due to eyelid deformity, inflammation and the absence of donor skin. Timely full-thickness skin grafting and blepharorrhaphy are effective approaches to preventing exposure keratopathy. To severe ulcers occur, conjunctival flap or Tenon's capsule covering combined with eyelid EFTSG and tarsorrhaphy is useful to rescue visual function.

[A case of Stevens-Johnson syndrome with binocular corneal perforation and multiple corneal transplantation which was difficult to control]

The 31-year-old female patient was admitted to the General Hospital of the Chinese People's Liberation Army for 3 days after the corneal transplantation of her right eye for 5 months.Four years ago, the patient developed red eyes, pain, dryness and photophobia after intravenous drip of cefuroxime sodium and metronidazole due to pelvic inflammation, accompanied by high fever, systemic rash and epidermal exfoliation, fingernail peeling, and mucosal ulceration in the eyes and mouth.Later, the patient received systemic hormone shock and point eye treatment in a local hospital, and the dry eyes gradually worsened. Despite continuous artificial tears and bandage mirror treatment, the corneal ulcer perforation in both eyes still occurred successively. After several penetrating keratografts and drug therapy, the ulcer and dissolution could not be prevented. He was admitted to our hospital due to corneal perforation in both eyes.Ophthalmic examination: visual acuity manual/15 cm in the right eye, intraocular pressure T-2, conjunctival sac stenosis, extensive corneal opacity and edema, ulcer about 8 mm, corneal perforation near the corneal limbus about 2 mm×5 mm below.The left eye had no light perception, a central corneal ulcer of about 8 mm, bulge of the posterior elastic layer, no anterior chamber, and atrophy of the eyeball.B-ultrasound showed choroidal detachment of the right eye.On the second day, the patient received right eye intraocular exploration, vitrectomy, ecotopic keratoscleral carrier Boston Ⅱ artificial keratoplasty, glaucoma valve implantation, autogenous ear cartilage implantation, conjunctival occlusion, and left eye lamellar keratoplasty, conjunctival occlusion.Postoperative visual acuity of right eye was -6.50 DS=0.12, intraocular pressure TN, ocular surface was stable.The left eye has no light perception and the ocular surface is stable.

[The research progress of mesenchymal stem cell induction and differentiation into corneal tissue]

Keratopathy is one of the most important blinding eye diseases in the world. Corneal opacity caused by keratopathy can seriously damage visual function. For example, corneal ulcer can lead to perforation and even loss of the eyeball. Although corneal transplantation is a routine treatment in clinical practice, there are not only a serious shortage of corneal donors in our country, but also various complications after keratoplasty that can not be avoided. In recent years, with the rapid development of regenerative medicine, it has been found that mesenchymal stem cells can differentiate into a variety of functional cells including corneal tissue under suitable induction conditions, which has a broad prospect of clinical application. This finding provides new ideas and methods for the treatment of keratopathy and corneal blindness in many aspects. This article reviews the research status of induction methods of mesenchymal stem cells in various specialties, particularly in the corneal subspecialty.

[Fuchs corneal endothelial dystrophy treated with Descemet's stripping without endothelial keratoplasty (DWEK): a case report]

A patient with chief complaint of bilateral progressive visual impairment was diagnosed with Fuchs corneal dystrophy (FECD) in both eyes, macular hole in the left eye, and intraocular lens eye in the right eye. After communication with the patient and his family, they agreed to receive Descemet's stripping without endothelial keratoplasty (DWEK) in the left eye. One year after the operation, the cornea of the left eye was transparent, and the central posterior elastic layer was missing about 4.0 mm diameter. The naked vision of left eye was 0.1, and the correction was not improved. It can be seen that DWEK surgery has a good therapeutic effect on patients with mild FECD.

[Recommendations of diagnosis and treatment of juvenile idiopathic arthritis in China]

The common clinical subtypes of juvenile idiopathic arthritis (JIA) include systemic onset juvenile idiopathic arthritis (SOJIA), oligoarthritis/polyarthritis juvenile idiopathic arthritis and juvenile spondyloarthritis. Juvenile idiopathic arthritis has no specific diagnostic index, and needs to be differentiated from infectious diseases and malignant diseases. The onset of SOJIA is rapid, the disease progresses rapidly, and it is easy to be complicated with macrophage activation syndrome (MAS) which is life-threatening. The experience of pediatric rheumatologists in dealing with JIA is still insufficient, and the standardized diagnosis and treatment level of this disease needs to be further improved. Based on the experience and guidelines of diagnosis and treatment in China and abroad, we formulated this diagnosis and treatment standard, aiming at standardizing the diagnosis and treatment of the subtypes of JIA and MAS, so as to reduce the incidence of disability and serious complications and improve the prognosis.

Identification of differentially expressed long non-coding RNAs and messenger RNAs involved with muscle development in Dazu black goats through RNA sequencing

This study aimed to explore the genetic basis of muscle development in goats. The transcriptome dataset for differentially expressed lncRNAs (DELs) and differentially expressed genes (DEGs) of goat muscle at different developmental stages were obtained using RNA-Seq. A total of 447,806,481 and 587,559,465 clean reads in the longissimus dorsi muscle of Dazu black goats between 75d embryonic stage and 1d after birth were generated through Illumina paired-end sequencing, and their mapping rates were 89.82 and 90.99%, respectively. Moreover, 4517 DEGs and 648 DELs were identified, and 4784 lncRNA-mRNA targeting relationships were predicted. Gene function annotation results showed that 4101 DEGs were significantly enriched to 1098 GO terms, and 2014 DEGs were significantly enriched to 40 KEGG pathways, including many GO terms and pathways related to muscle development, such as cell differentiation and Wnt signaling pathway. Then, 10 DELs and 20 DEGs were randomly selected for RT-qPCR verification, and the agreement rate between the verification and RNA-Seq results was 90%, indicating the high reliability of the RNA-Seq data analysis. In conclusion, this study obtained several mRNAs and lncRNAs related to the muscle development of Dazu black goats and identified several targeted regulatory pairs of lncRNA-mRNA. This study may serve as a reference to understand the genetic basis and molecular mechanism of muscle development in goats.

[Study on the etiological characteristics and prevention and control of adult community-acquired pneumonia in hospitalized patients in a hospital in Beijing from 2015 to 2019]

Objective: To explore the distribution characteristics of pathogens in adult patients with community-acquired pneumonia (CAP) and to provide basis for the diagnosis, treatment, prevention of CAP. Methods: 1 446 inpatients with CAP were prospectively enrolled in a third-class hospital in Beijing in recent 5 years (from January 2015 to December 2019). Respiratory tract samples were collected for smear, culture, nucleic acid, antigen and antibody detection to identify the pathogen of CAP. Mann-Whitney U test was used for continuous variables and χ² test or Fisher's exact test was used for categorical data for statistical analysis. Results: Among the 1 446 patients, 822 (56.85%) patients were infected with a single pathogen, 231 (15.98%) patients were infected with multiple pathogens, and 393 (27.18%) patients were not clear about the pathogen. Influenza virus is the first pathogen of CAP (20.95%, 303/1 446), mainly H1N1 (8.51%, 123/1 446), followed by mycoplasma pneumoniae (7.19%, 104/1 446), Mycobacterium tuberculosis (5.33%, 77/1 446) and Streptococcus pneumoniae (5.05%, 73/1 446). The outbreak of H1N1 occurred from December 2018 to February 2019, and the epidemic of mycoplasma pneumoniae pneumonia was monitored from August to November 2019. Patients under 65 years old had high detection rates of Mycoplasma pneumoniae (14.41% vs. 2.41%, χ²=74.712,P<0.001), Streptococcus pneumoniae (8.16% vs. 2.99%, χ²=18.156, P<0.001), rhinovirus (6.08% vs. 3.56%, χ²=5.025, P<0.025), Chlamydia pneumoniae (5.90% vs. 1.15%, χ²=26.542, P<0.001) and adenovirus (3.13% vs. 0.92%, χ²=9.547, P=0.002). The severe disease rate of CAP was 14.66% (212/1 446), and the average mortality rate was 3.66% (53/1 446). The severe illness rate and mortality rate of bacterial-viral co-infection were 28.97% (31/107) and 19.63% (21/107), respectively. Conclusions: Influenza virus is the primary pathogen of adult CAP. Outbreaks of Mycoplasma pneumoniae and H1N1 were detected in 2018 and 2019, respectively. The remission rate and mortality rate of virus-bacteria co-infection were significantly higher than those of single pathogen infection. Accurate etiological basis not only plays a role in clinical diagnosis and treatment, but also provides important data support for prevention and early warning.

[Ultrastructural features of the corneal epithelium with micromolecular compound J2 in the corneal allograft of rats using atomic force microscopy]

Objective: To study the ultrastructural features of the corneal epithelium in the corneal allograft of rats with micromolecular compound J2. Methods: An experimental study. Primarily cultured corneal epithelial cells of rats were used. Mononuclear cells (MNCs) by density gradient centrifugation were assigned into the experimental group [MNCs (2 ml)+corneal epithelial cells+J2], control group [MNCs (2 ml)+corneal epithelial cells] and blank group (corneal epithelial cells). Quantity of CD80 expression was obtained by flow cytometry after coculture. Amplitude and height images were obtained by tapping mode atomic force microscopy (AFM) with a scan rate of 2 Hz and an integral gain of 0.3 to 0.5. Statistical analysis of Ra, Rq, Rvm and Rt was performed using the single-factor analysis of variance, and P value was calculated. Results: There were obvious differences in the ultrastructure measured by AFM among groups. Ra was 86.75±12.60 in the experimental group, 120.23±12.11 in the control group, and 61.94±10.62 in the blank group (F=306.92, P<0.01). Rq was 102.53±9.45, 138.30±10.13, and 91.96±7.25, respectively, in the three groups (F=361.85, P<0.01). Rvm was -42.21±14.22, -67.36±10.89, and -32.18±19.01, respectively (F=72.22, P<0.01). Rt was 437.32±15.66, 495.32±13.96, and 339.92±11.22, respectively (F=1634.26, P<0.01). The one way analysis of variance showed significant differences in these parameters among groups. Conclusions: Corneal epithelial cells of rats activated by MNCs had higher CD80 expression, but the expression became decreased with micromolecular compound J2. The ultrastructure of the corneal epithelium became coarser after MNCs activation, and the number of protrusions increased significantly. The ultrastructural changes were alleviated by J2.(Chin J Ophthalmol, 2021, 57: 608-613).

The crystal structure of 13-(pyrazole-1-yl-4-carbonitrile)-matrine, C19H25N5O

C19H25N5O, monoclinic, P21 (no. 4), a = 16.0600(2) Å, b = 5.3992(1) Å, c = 19.8514(2) Å, β = 94.260(1)°, V = 1716.58(4) Å3, Z = 4, R gt (F) = 0.0350, wR ref(F 2) = 0.0908, T = 100.00(10) K.

Common vetch varietal differences in hay nutritive value, ruminal fermentation, nutrient digestibility and performance of fattening lambs

In some lower rainfall regions of the world (300-750 mm), common vetch (Vicia sativa L., hereafter referred to as vetch) has been shown to have yields competitive with alternate crops and provide high-quality hay for ruminant diets, but there are few studies of vetch performance as a livestock feed, or of vetch varietal differences in livestock feeding value. This study evaluated vetch varietal differences in hay nutritive value, ruminal fermentation properties, nutrient digestibility, nitrogen retention and animal performance in fattening lambs consuming a diet comprising 20% vetch. Fifty male Hu lambs with an initial BW of 17.7 ± 0.27 kg and 2-3 months of age were assigned randomly into five groups of 10 lambs, and each allocated one of five dietary treatments for 67 days (10 days of adaptation and a 57 day experimental period). All diets contained 30% maize stover, 50% concentrate, and with a different forage source (on an as-fed basis): 20% alfalfa hay (Control), 20% vetch 333A (C333A) hay, 20% vetch Lanjian No. 1 (CLJ1) hay, 20% vetch Lanjian No. 2 (CLJ2) hay, or 20% vetch Lanjian No. 3 (CLJ3) hay. Hay CLJ3 had greater contents of ash, CP, ether extract, in vitro organic matter digestibility and metabolizable energy, and lower cell wall contents (P < 0.05) than those of C333A and CLJ1 hays, but similar to the CLJ2 hay (P > 0.05). Compared to the Control diet, the CLJ2 and CLJ3 diets resulted in greater (P < 0.05) final BW, average daily gain, total tract apparent digestibility of CP and NDF, and nitrogen balance, both when expressed as g/day and relative to nitrogen intake, while animal performance when fed diets with C333A or CLJ1 diet did not differ (P > 0.05) from the Control diet. No differences (P > 0.05) were observed between dietary treatments with respect to average daily feed intake, ruminal pH, total volatile fatty acid contents and molar proportions of acetate, butyrate, valerate, isobutyrate, and isovalerate, or total tract apparent digestibility of DM, organic matter, and ADF. The feed efficiency of tested feeds ranked CLJ3 = CLJ2 > CLJ1 > Control with C333A intermediate between CLJ1 and Control. In summary, considering hay quality, nutrient digestibility and animal weight gain, performance as a ruminant feed of hays from recently released vetch cultivars Lanjian No. 2 and Lanjian No. 3 was superior to the older cultivar C333A and the alfalfa control.

Three SNPs within exons of INHA and ACVR2B genes are significantly associated with litter size in Dazu black goats

The aim of this study was to analyse the association between single-nucleotide polymorphisms within INHA and ACVR2B and litter size in Dazu black goats. In total, twenty-two SNPs were genotyped in 190 individuals by SNaPshot and resequencing. The results showed that three SNPs (SNP_1, SNP_12 and SNP_13 in this study) were detected to have significant additive genetic effect on the recorded goat litter size (p < .05). The SNP_1 (NC_030809.1), a non-synonymous substitution of G for T at chr2-g. 28314990 in the exon 2 of INHA gene (NM_001285606.1), resulted in homozygote 2 (HOM2) contributed 0.25 and heterozygote (HET) contributed 0.12 larger litter than homozygote 1 (HOM1). Meanwhile, SNP_12 (Chr22-g. 11721225 A > T) and SNP_13 (Chr22-g. 11721227 A > C) (NC_030829.1) simultaneously mutated at the first and third position of a triplet AAA (lysine, K) in the exon 4 of ACVR2B gene (XM_018066623.1) had estimated genetic effects of HOM1 (0.00) and HOM2 (0.03) larger than HET (-0.12). In conclusion, one SNPs (chr2-g. 28314990 T > G) within the exon 2 of INHA and two SNPs (Chr22-g. 11721225 A > T and Chr22-g. 11721227 A > C) in the exon 4 of ACVR2B gene were highly recommended as candidate markers of litter size in Dazu black goats. A large-scale association study to assess the impact of these variants on litter size is still necessary.

Identification of a Goat Intersexuality-Associated Novel Variant Through Genome-Wide Resequencing and Hi-C

Background: Polled intersex syndrome (PIS) leads to reproductive disorders in goats and exerts a heavy influence on goat breeding. Since 2001, the core variant of an 11.7 kb deletion at ~129 Mb on chromosome 1 (CHI1) has been widely used as a genetic diagnostic criterion. In 2020, a ~0.48 Mb insertion within the PIS deletion was identified by sequencing in XX intersex goats. However, the suitability of this variation for the diagnosis of intersex goats worldwide and its further molecular genetic mechanism need to be clarified.

Results: The whole-genome selective sweep of intersex goats from China was performed with whole-genome next-generation sequencing technology for large sample populations and a case–control study on interbreeds. A series of candidate genes related to the goat intersexuality phenotype were found. We further confirmed that a ~0.48 Mb duplicated fragment (including ERG and KCNJ15) downstream of the ~20 Mb PIS region was reversely inserted into the PIS locus in intersex Chinese goats and was consistent with that in European Saanen and Valais black-necked goats. High-throughput chromosome conformation capture (Hi-C) technology was then used to compare the 3D structures of the PIS variant neighborhood in CHI1 between intersex and non-intersex goats. A newly found structure was validated as an intrachromosomal rearrangement. This inserted duplication changed the original spatial structure of goat CHI1 and caused the appearance of several specific loop structures in the adjacent ~20 kb downstream region of FOXL2.

Conclusions: Results suggested that the novel complex PIS variant genome was sufficient as a broad-spectrum clinical diagnostic marker of XX intersexuality in goats from Europe and China. A series of private dense loop structures caused by segment insertion into the PIS deletion might affect the expression of FOXL2 or other neighboring novel candidate genes. However, these structures require further in-depth molecular biological experimental verification. In general, this study provided new insights for future research on the molecular genetic mechanism underlying female-to-male sex reversal in goats.

A nonsynonymous SNP within the AMH gene is associated with litter size in Dazu black goats

AMH, KISS1R and GDF9 genes play a vital role in human and animal reproduction and might be used as the genetic markers for the reproduction traits selection. The aim of this study was to screen the single nucleotide polymorphisms (SNPs) within the AMH, KISS1R and GDF9 genes and to determine the correlations between these SNPs and the litter size in goats. Nine single SNPs within these genes were used for genotyping of the 190 Dazu black goat populations by SNaPshot technique. The polymorphisms of nine SNPs within these genes were detected in Dazu black goats. The significant correlation was observed between one SNP (g.89172108A > C) within the AMH gene and the litter size of second born in Dazu black goats (p < 0.05). The SNP was located in exon 4 (XM_018050765.1) of the AMH gene and was one nonsynonymous substitution, which resulted in a change of an amino acid from Glutamine to Proline (Gln38Pro). These results suggested that the nonsynonymous SNP g.89172108A > C of AMH gene could be used as a potential genetic marker for Marker-assisted selection (MAS) in goats breeding programs.

[Problems and challenges in the development of keratoprosthesis surgery in China]

Keratoprosthesis implantation as an effective therapeutic method has been a treatment strategy in end-stage corneal blindness, contributing to restore vision and reduce the prevalence of blindness, but it has been restricted because of its high surgical technique and devastating complications. There are a large number of patients with corneal blindness in China, and the rate of high-risk or end-stage corneal blindness is high. It is of great significance to improve the understanding of the indications and contraindications of different kinds of keratoprostheses, as well as relevant technologies and knowledge, cope with the problems and challenges in the development period, and conduct safe and efficient clinical applications and related research, so that the technology of keratoprosthesis implantation in our country can go to the world steadily. (Chin J Ophthalmol, 2020, 56: 730-734).

[A case of difficult extubation after tracheotomy in a child with severe scald of oropharynx]

In November 4, 2016, a 1 year and 3 months old male patient with face and neck scald complicated with severe scald of oropharynx was admitted to Guangzhou Red Cross Hospital 1 hour after injury. The child developed upper respiratory tract obstruction 2 hours after injury, therefore tracheotomy and intubation were performed immediately to establish an artificial airway, and symptomatic treatments such as anti-infection, fluid replacement, and dressing change were conducted. On the 10th day after injury, the child had difficult breathing during the test tube blocking before extubation, and it was difficult to extubate. Symptomatic treatments such as ventilator assisted ventilation and strengthened anti-infection were continued. On the 17th day after injury, extubation plan was adjusted. Thirty minutes before extubation, phenobarbital was injected intramuscularly for sedation, and atropine was used to reduce airway secretions, after which extubation was successful. After 21 days of treatment, the child was cured and discharged. In the treatment of this case, high attention was paid to the important influence of children's mental factors among causes of difficult extubation, which provided a reference for clinical treatment of extubation in children with tracheal tube after tracheotomy.

Evolutionary relationship and population structure of domestic Bovidae animals based on MHC-linked and neutral autosomal microsatellite markers

Major histocompatibility complex (MHC) genes are critical for disease resistance or susceptibility responsible for host-pathogen interactions determined mainly by extensive polymorphisms in the MHC genes. Here, we examined the diversity and phylogenetic pattern of MHC haplotypes reconstructed using three MHC-linked microsatellite markers in 55 populations of five Bovidae species and compared them with those based on neutral autosomal microsatellite markers (NAMs). Three-hundred-and-forty MHC haplotypes were identified in 1453 Bovidae individuals, suggesting significantly higher polymorphism and heterozygosity compared with those based on NAMs. The ambitious boundaries in population differentiation (phylogenetic network, pairwise F_ST and STRUCTURE analyses) within and between species assessed using the MHC haplotypes were different from those revealed by NAMs associated closely with speciation, geographical distribution, domestication and management histories. In addition, the mean F_ST was significantly correlated negatively with the number of observed alleles (N_A), observed (H_O) and expected (H_E) heterozygosity and polymorphism information content (PIC) (P < 0.05) in the MHC haplotype dataset while there was no correction of the mean F_ST estimates (P> 0.05) between the MHC haplotype and NAMs datasets. Analysis of molecular variance (AMOVA) revealed a lower percentage of total variance (PTV) between species/groups based on the MHC-linked microsatellites than NAMs. Therefore, it was inferred that individuals within populations accumulated as many MHC variants as possible to increase their heterozygosity and thus the survival rate of their affiliated populations and species, which eventually reduced population differentiation and thereby complicated their classification and phylogenetic relationship inference. In summary, host-pathogen coevolution and heterozygote advantage, rather than demographic history, act as key driving forces shaping the MHC diversity within the populations and determining the interspecific MHC diversity.

SNP of AHSA2 gene in three cattle breeds using snapshot technology

Droughtmaster is a tropical breed of beef cattle that can survive in hot climates and easily adapt to torrid environments. These traits are important in livestock breeding. In this study, we genotyped five single-nucleotide polymorphisms (SNPs) of the AHSA2 gene from 190 cattle belonging to three different breeds (Droughtmaster, Angus and Simmental) by using snapshot technology. This work aimed to identify the valuable molecular marker of heat resistance in cattle. Results showed that Droughtmaster exhibited higher expected heterozygosity and polymorphic information content compared with the two other breeds. The AHSA2-1 locus deviated from the Hardy-Weinberg equilibrium in the Droughtmaster breed (P < 0.05). Two SNPs in Droughtmaster diverged significantly from Angus and Simmental. The SNPs were identified as AHSA2-3 and AHSA2-4, which were closely linked to the three breeds based on pair-wise FST. AHSA2-4 involved a missense mutation. In summary, the GG genotypes in AHSA2-3 and AHSA2-4 may be candidate genotypes associated with heat resistance traits and may serve as valuable genetic markers for breeding of heat-tolerant beef cattle in the future.

Genome-wide selection signatures analysis of litter size in Dazu black goats using single-nucleotide polymorphism

Litter size is considered to be the most important index for estimating domestic animal productivity. The number of indigenous goats in China with higher litter sizes than those of commercial breeds in other countries may be helpful for accelerating genetic improvements in goat breeding. We performed a genome-wide selective sweep analysis of 31 Dazu black goats with extreme standard deviation in litter size within the third fetus to identify significant genomic regions and candidate genes through different analyses. The analysis identified a total of 33,917,703 variants, including 32,262,179 SNPs and 1,655,524 indels. In addition, two novel candidate genes (LRP1B and GLRB), which are related to litter size, were obtained with π, Tajima's D, πA/πB, and F _ST at the individual level with a 95% threshold for each parameter. These two genes were annotated in five GO terms (localization, binding, macromolecular complex, membrane part, and membrane) and two pathways (long-term depression and neuroactive ligand-receptor interaction pathway). Regarding the result of linkage disequilibrium (LD) analysis, in LRP1B and GRID2, the high-yield Dazu black goats exhibit significantly different LD patterns from low-yield goats. Litter size variability has low heritability and is related to multiple complex factors found in domestic animals. Obtaining a clear explanation and significant signal by genome-wide selective sweep analysis with a small sample size is difficult. However, we investigated some candidate genes, particularly LRP1B and GLRB, which may provide useful information for further research.

[Clinical characteristics of malignant peritoneal mesothelioma misdiagnosed as tuberculous peritonitis: a report of 6 cases]

Objective: To reduce the misdiagnosis rate of ascites and improve the diagnosis rate of malignant peritoneal mesothelioma. Methods: From May 2008 to May 2018, in Xiangya Hospital of Central South University,the clinical data of malignant peritoneal mesothelioma misdiagnosed as tuberculous peritonitis were retrospectively analyzed. Results: (1) Among the 6 patients, they were male; the age of onset was 42-70 (52±9.57) years old, and there was no history of asbestos exposure. (2) All cases with abdominal pain or abdominal distension were there and the course of disease was more than 1 month to more than 2 years. (3) In all patients,the nature of ascites was exudate; ADA was higher than normal value and below 45 U/L; LDH value in ascites was higher than 200 U/L (83.3%); mesothelioma was considered in ascites cytology in 1 case. (4) Laparoscopic biopsy was performed in 2 cases and B-ultrasound guided biopsy in 4 cases; Among them, malignant peritoneal mesothelioma diagnosed by pathology. (5) In Immunohistochemical positive markers, MC was the most sensitive (100%), followed by CR (67%), CK-Pan (67%), Ki-67 (67%) and EMA (67%). (6) Two patients received treatment with operation, abdominal hyperthermic perfusion and postoperative systemic chemotherapy. Conclusions: (1) Malignant peritoneal mesothelioma should be considered in middle-aged and aged male patients with unexplained ascites and early laparoscopy or laparotomy for diagnosis. (2) ADA and LDH level in ascites are significant in differentiating tuberculous peritonitis from malignant peritoneal mesothelioma. (3) Immunohistochemical positive marker MC may be a potential specific marker for malignant mesothelioma. (4) The survival time of patients is improved by comprehensive treatment such as operation and chemotherapy.

[Advances in the fenestrated stent-graft and the stent-graft for the in-situ fenestration technique]

The endovascular exclusion is an effective treatment of aortic aneurysm diseases in frail and elderly patients who cannot suffer the open surgery. However, as the key treatment device of this technique, traditional stent-grafts are not suitable to treat complex aortic aneurysm diseases in emergency. The emergence of the fenestrated stent-graft and in-situ fenestration has brought new dawn to the treatment of these patients. This study reviews the advances in complex aortic aneurysms treated by the fenestrated stent-graft and the in-situ fenestration. In addition, the novel concept of the fabric structure designed for "in-situ fenestrated stent-graft" is proposed for the in-situ fenestration technique. It is expected to break through the bottleneck of the present fenestrated stent-grafts. It would be beneficial to the bailout of complex aortic aneurysm diseases and thereby benefitting more patients.

Current genetic diversity in eight local Chinese sheep populations

China has numerous local domestic sheep breeds. In this study, the genetic diversity of eight sheep populations was estimated using 17 microsatellites. Knowledge of such diversity provides novel insight into the degree of breed protection needed and the prediction of hybrid advantage. In total, 17 microsatellites were genotyped in 186 individuals from eight populations. The mean number of alleles (± SD) ranged from 3.71 ± 1.36 in Zhaotong sheep to 11.94 ± 3.58 in small-tailed Han sheep. The observed heterozygote frequency (± SD) within a population ranged from 0.482 ± 0.025 in Zhaotong sheep to 0.664 ± 0.023 in Tibetan sheep. In addition, using pairwise difference (F_ST) analysis, the highest within-population diversity was observed in Tibetan sheep (πX = 12.8098) and small-tailed Han (πX = 12.67873), and the lowest diversity was observed in Zhaotong sheep (πX = 7.90337). The results for genetic divergence between populations indicated that the populations were significantly different (P < 0.05) based on the average number of pairwise differences between populations (πXY) and the corrected average pairwise differences. Both phylogenetic networks and structure analysis showed that these eight populations were separated into three clusters in accordance with their geographical habitat, except Tibetan and Hu sheep. In short, we genotyped eight local Chinese sheep populations using 17 microsatellites, and the results indicated that their current genetic diversity is decreasing and that new conservation strategies are needed. In addition, significant genetic differences between populations could be used in cross breeding.

Incidence and risk factors of osteomyelitis in adult and pediatric systemic lupus erythematosus: a nationwide, population-based cohort study

OBJECTIVE

The objective of this paper is to investigate the incidence rate, risk factors and outcome of osteomyelitis among patients with systemic lupus erythematosus (SLE).

MATERIALS AND METHODS

We conducted a cohort study using data for patients enrolled in the Taiwan National Health Insurance Database from 2000 to 2012. Patients with SLE and age- and sex-matched controls without SLE were enrolled. Primary endpoint was the first occurrence of osteomyelitis. Risks of osteomyelitis in SLE patients were analyzed with Cox proportional hazards regression models, including age, sex, comorbidities and medications.

RESULTS

Among 24,705 SLE patients (88.4% women, mean age 35.8 years) with a median follow-up of 9.1 years, 386 patients had osteomyelitis. The incidence rate ratio (IRR) of osteomyelitis in the SLE group vs the control group was 8.52 (95% confidence interval (CI) 7.24-10.05). The SLE group had higher incidence rates of osteomyelitis than the control group, especially in pediatric subgroups (IRR 41.1 95% CI 18.57-107.35). Compared to controls, SLE patients experienced osteomyelitis at a younger age (42.3 vs 58.1 years) but did not have an increased risk of mortality (hazard ratio 0.7; 95% CI 0.21-2.38). Age >60 years, male gender, malignancy within five years, prior bone fracture and higher daily prednisolone dose (>7.5 mg) cumulatively for >180 days increased risk for osteomyelitis.

CONCLUSIONS

SLE patients have a higher IRR of osteomyelitis than controls. Pediatric and elder SLE patients, patients with a history of bone fracture, malignancy within five years and higher-dose glucocorticoid use have a higher risk of osteomyelitis and should be carefully monitored.

Obesity-associated cardiac pathogenesis in broiler breeder hens: Development of metabolic cardiomyopathy

Feed intake is typically restricted (R) in broiler hens to avoid obesity and improve egg production and livability. To determine whether improved heart health contributes to improved livability, fully adult 45-week-old R hens were allowed to consume feed to appetite (ad libitum; AL) up to 10 wk (70 d). Mortality, contractile functions, and morphology at 70 d, and measurements of cardiac hypertrophic remodeling at 7 d and 21 d were made and compared between R and AL hens. Outcomes for cardiac electrophysiology and mortality, reported separately, found increased mortality in AL hens in association with cardiac pathological hypertrophy and contractile dysfunction. The present study aimed to delineate metabolic cardiomyopathies underlying the etiology of obesity-associated cardiac pathology. Metabolic measurements were made in hens continued on R rations or assigned to AL feeding after 7 d and 21 days. AL feeding increased plasma insulin, glucose, and non-esterified fatty acid (NEFA) concentrations by 21 d (P < 0.05). Metabolic cardiomyopathy in AL-hens was confirmed by cardiac triacylglycerol (TG) and ceramide accumulation consistent with up-regulation of related enzyme gene expressions, and by increased indices of oxidation stress (P < 0.05). In contrast to R hens, cardiac pyruvate dehydrogenase (PDH) activity and glucose transporter (GLUT) gene expressions increased progressively while carnitine palmitoyltransferase-1 (CPT-1) transcript levels in AL hens declined from 7 d to 21 d (P < 0.05), reflecting a shift from an oxidative to a more glycolytic metabolism, a typical metabolic derangement associated with cardiac hypertrophic remodeling. Cardiac pathogenesis in AL hens was further indicated by increased leukocyte infiltrates, interleukin-1β (IL-1β) and IL-6 production, cellular apoptosis, interstitial fibrosis, and expression of the heart failure marker myosin heavy chain (MHC-β; cardiac muscle beta) (P < 0.05). Results support the conclusion that diabetic conditions, cardiac inflammation and lipotoxic metabolic derangements act as pathological cues to trigger pathogenic changes along cardiac hypertrophy in AL hens.

[Research on natural antioxidants in the treatment of retinal degeneration]

Retinal degeneration (RD) is a common eye disease which may result in blindness. At present, there is no effective clinical treatment for RD. It is known that apoptosis causes the occurrence and development of retinal degeneration, therefore antiapoptotic/antioxidative treatment has always been the focus in the treatment of RD. There are many kinds of antioxidant drugs, among which natural antioxidants are featured with reliable sources, high safety and less side effects. Hence researchers across the world made tremendous efforts in finding the safe and effective natural antioxidants. This paper focuses on the research progress of natural antioxidants in the treatment of retinal degeneration, in an effort to provide some valuable reference for clinical research. (Chin J Ophthalmol, 2018, 54: 312-315).

Reversibility and safety of KISS1 metastasis suppressor gene vaccine in immunocastration of ram lambs

Objective

The aim of this study was to investigate the reversibility and safety of KISS1 metastasis suppressor (KISS1) gene vaccine in immunocastration.

Methods

Six eight-week old ram lambs were randomly divided into vaccinated and control groups. The vaccine (1 mg/ram lamb) was injected at weeks 0, 3, and 6 of the study. Blood samples were collected from the jugular vein before primary immunization and at weeks 2, 4, 6, 10, 14, 22, and 30 after primary immunization. All ram lambs were slaughtered at 38 weeks of age, and samples were collected.

Results

The specific anti-KISS1 antibody titers in vaccinated animals were significantly higher and the serum testosterone level was significantly lower than those in the control groups from week 4 to 14 after primary immunization (p<0.05). No significant difference was observed at weeks 22 and 30 after the primary immunization. Similar results were also found for scrotal circumference, testicular weight, length, breadth, and spermatogenesis in seminiferous tubules in week 30 after primary immunization. KS (KISS1-hepatitis B surface antigen S) fusion fragment of KISS1 gene vaccine was not detected in host cell genomic DNA of 9 tissues of the vaccinated ram lambs by polymerase chain reaction.

Conclusion

The effects of KISS1 gene vaccine in immunocastration were reversible and no integration events were recorded.

Production of medically useful nitric monoxide using AC arc discharge

Inhaled nitric monoxide (iNO) is increasingly used as a medical treatment for acute respiratory distress syndrome. A course of the existing nitric monoxide (NO) therapy with gas cylinders could cost up to approximately $15,000 for an average of 30.2 h. Moreover, a gas cylinder containing a mixture of N₂ and NO may potentially leak NO. The objective of this study is to develop an efficient and cost-effective on-site iNO generation system. In the present setup, NO was generated by using dry air or mixed oxygen/nitrogen (O₂/N₂) and an AC power source with an output power level of 5-30 W at atmospheric pressure. The simultaneously produced NO₂ was eliminated with an ammonium sulfite ((NH₄)₂SO₃) solution. The effects of the O₂/N₂ ratio, gas flow rate, discharge gap distance, output energy density and electrode structure on NO_x concentration and the NO/NO₂ ratio are reported. The concentrations of NO and NO₂ reached 62 ppm and 3 ppm, respectively, after absorption and dilution at a gas flow rate of 6 L/min. With the present setup, the AC arc discharge produced NO_x at a stable concentration for at least 6 h using dry air.

Sheep mitochondrial heteroplasmy arises from tandem motifs and unspecific PCR amplification

The mitochondrial DNA control region (D-loop) is a widely used molecular marker in evolutionary and phylogeographic research. However, the occurrence of heteroplasmy of the D-loop region within individuals has rarely been investigated. In this study, a total of 85 Chinese sheep were used to amplify a partial D-loop region, and 15 heteroplasmic animals (17.64%) were identified. A comparative analysis of the PCR amplification and cloning of the D-loop sequences from the heteroplasmic samples revealed most of the sequencing profile from the heteroplasmic regions started at the beginning of a 75-bp random repeat motif. In addition, a total of 22 nonsyngeneic sequences with a D-loop were found in 61 of the clones obtained from the 4 random heteroplasmic and 3 homozygote animals, and their genomic locations were compared for homology. In summary, the D-Loop sequencing profiles appear to be heteroplasmic and could arise from tandem repeat motifs and unspecific replication during PCR amplification; however, they are not likely due to the presence of multiple mitochondrial genomes within an individual.

[An experimental study of mesenchymal stem cells in tissue engineering scaffolds implanted in rabbit corneal lamellae to increase keratoprosthesis biointegration]

OBJECTIVE

To complete a preliminary evaluation of the feasibility of implanting the complex of mouse bone marrow mesenchymal stem cells (BMSC) and a tissue engineering scaffold into rabbit corneal lamellae, based on which a solution may be proposed to consolidate the keratoprosthesis and the recipient surface, and to reduce the risk of complications.

METHODS

This experimental study was composed of two parts. (1) In vitro: some mouse BMSC were marked with red fluorescent proteins (RFP) and integrated with a decellularized pig articular cartilage extracellular matrix (ECM) scaffold. The cell survival was observed under a fluorescence microscope at 4 and 8 weeks. The cell distribution was examined by toluidine blue staining. The pore structure and the cell adhesion were observed under a scanning electron microscope. (2) in vivo: the complex of mouse BMSC and a decellularized scaffold was implanted into the lamellar cornea of 8 rabbit eyes with the fellow eyes as the controls. The eyes were sampled for observation using HE staining under a light microscope at 2, 4 and 8 weeks, respectively. The cell survival was examined under a fluorescence microscope, and the intracorneal cell survival at 8 weeks was observed using in vivo imaging. The conditions of ocular anterior segment of all the experimental animals were recorded.

RESULTS

(1) Under the scanning electron microscope, the ECM scaffolds showed satisfactory porosity required for the adhesion and growth of cells and tissues, and the cell distribution over the cell-scaffold complex can be observed by toluidine blue staining. (2) Under the immunofluorescence microscope, cell proliferation was observed in vitro and in the interlamellar space (the maximum observation time was 8 weeks) after the RFP-marked mouse BMSC were integrated in vitro with ECM scaffolds. (3) Under the light microscope (HE staining), the stromal cells were detected to increase at each timepoint. A small number of monocytes and some mouse BMSC were observed in the superficial layer of corneal stroma, with sparsely and orderly arranged collagenous fibers and no neovascularization. All the epithelial cells appeared as mononuclear, columnar and undamaged, and the shape of ECM scaffolds, which were fused with the collagens, became unclear. (4) By in vivo imaging, it was found that the mouse BMSC survived for 8 weeks after being integrated with scaffolds and implanted into the interlamellar space of rabbit cornea. (5) After the implantation of cell-scaffold complex, severe postoperative inflammatory reactions, obvious conjunctival congestion and neovascularization were not observed. The corneal tissues surrounding the recipient area were transparent. One week later, mild inflammatory reactions were barely observed, and the cornea was transparent enough to observe the scaffold in the stromal layers. Four weeks later, the scaffolds became thinner. Eight weeks later, the scaffolds became extremely thin with normal vascular system in the corneal limbus.

CONCLUSIONS

The ECM scaffold is a solid and biocompatible carrier for the growth and proliferation of BMSC. The mouse BMSC can grow and proliferate in the microenvironment of the interlamellar space of cornea.

Desmoglein 4 diversity and correlation analysis with coat color in goat

Desmoglein 4 (DSG4) has an important role in the development of wool traits in domestic animals. The full-length DSG4 gene, which contains 3918 bp, a complete open-reading-frame, and encodes a 1040-amino acid protein, was amplified from Liaoning cashmere goat. The sequence was compared with that of DSG4 from other animals and the results show that the DSG4 coding region is consistent with interspecies conservation. Thirteen single-nucleotide polymorphisms (SNPs) were identified in a highly variable region of DSG4, and one SNP (M-1, G>T) was significantly correlated with white and black coat color in goat. Haplotype distribution of the highly variable region of DSG4 was assessed in 179 individuals from seven goat breeds to investigate its association with coat color and its differentiation among populations. However, the lack of a signature result indicates DGS4 haplotypes related with the color of goat coat.

The prevalence of leucocyte alloantibodies in blood donors from South China

BACKGROUND

Several studies had demonstrated that leucocyte antibodies including anti-human leucocyte antigen (anti-HLA) antibodies (class I and class II) and anti-human neutrophil antigen (anti-HNA) antibodies (HNA-1, -2 and -3) present in the blood products are responsible for transfusion-related acute lung injury (TRALI). Therefore, selection of blood products exclusive of anti-HLA and anti-HNA antibodies may lower the risk of TRALI reaction. However, the prevalence of leucocyte antibodies among blood donors in China is currently not known.

STUDY DESIGN AND METHODS

Blood samples were collected from 454 male and 560 female donors (143 nulliparous and 417 multiparous female). HLA class I and II antibodies were analyzed by bead assays. Anti-HNA-1 and -2 antibodies were screened by the LABScreen assay (One Lambda Inc.), and HNA-3 were detected by antigen capture assay, and confirmed by the granulocyte agglutination test (GAT).

RESULTS

Screening of the total cohort showed higher prevalence of HLA antibodies in female compared with male donors (19.64 vs. 4.63%). We found antibodies against HLA class I (13.21%) and HLA class II (11.43%) in 560 female donors. The most frequent antibodies against HLA class I and II in parous females (n = 69) reacted with were A*11 (28.81%), B*07 (42.37%), Cw*07 (20.34%) and DRB1*04 (40.43%) molecules. Among 778 donors (randomly selected from 1014 donors), we found three donors with neutrophil reactive antibodies, two against HNA-2 and one without known specificity. Anti-HNA-3 antibodies were not found so far.

CONCLUSION

In this study, we found alloimmunization against HLA class I, II and HNA in 4.63, 24.70 and 0.39%, respectively, in our female blood donors, indicating that the use of plasma containing blood products from parous female blood donors without HLA antibodies pre-testing may increase the risk of TRALI reaction. Although immunization against HNA seems to be a rare event in China, further observation is necessary to decide the necessity of HNA antibodies screening in our blood donors.

Conservation genetics in Chinese sheep: diversity of fourteen indigenous sheep (Ovis aries) using microsatellite markers

The domestic sheep (Ovis aries) has been an economically and culturally important farm animal species since its domestication around the world. A wide array of sheep breeds with abundant phenotypic diversity exists including domestication and selection as well as the indigenous breeds may harbor specific features as a result of adaptation to their environment. The objective of this study was to investigate the population structure of indigenous sheep in a large geographic location of the Chinese mainland. Six microsatellites were genotyped for 611 individuals from 14 populations. The mean number of alleles (±SD) ranged from 7.00 ± 3.69 in Gangba sheep to 10.50 ± 4.23 in Tibetan sheep. The observed heterozygote frequency (±SD) within a population ranged from 0.58 ± 0.03 in Gangba sheep to 0.71 ± 0.03 in Zazakh sheep and Minxian black fur sheep. In addition, there was a low pairwise difference among the Minxian black fur sheep, Mongolian sheep, Gansu alpine merino, and Lanzhou fat-tailed sheep. Bayesian analysis with the program STRUCTURE showed support for 3 clusters, revealing a vague genetic clustering pattern with geographic location. The results of the current study inferred high genetic diversity within these native sheep in the Chinese mainland.

A complete mitochondrial genome of Youzhou black-skin goat

The Youzhou black-skin goat (Capra hircus), an indigenous breed of Chinese southwest. Here, we describe the complete mitochondrial genome sequence of Hechuan white goat. The mitogenome is 16,640 nt in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.5%, T: 27.3%, C: 26.1% and G: 13.1%. The complete mitogenome of the local subspecies of Hechuan white goat could provide an important data to further breed improvement and animal genetics resource conservation in China.