[Analysis of the effects of low/intermediate dose of coagulation factor Ⅷ on 30 adult patients with severe hemophilia A in a single center]

Objective: To evaluate the clinical effects of low- and intermediate-dose factor Ⅷ (F Ⅷ) prophylaxis in Chinese adult patients with severe hemophilia A. Methods: Thirty adult patients with severe hemophilia A who received low- (n=20) /intermediate-dose (n=10) F Ⅷ prophylaxis at Nanjing Drum Tower Hospital affiliated with Nanjing University Medical College were included in the study. The annual bleeding rate (ABR), annual joint bleeding rate (AJBR), number of target joints, functional independence score of hemophilia (FISH), quality of life score, and health status score (SF-36) before and after preventive treatment were retrospectively analyzed and compared. Results: The median follow-up was 48 months. Compared with on-demand treatment, low- and intermediate-dose prophylaxis significantly reduced ABR, AJBR, and the number of target joints (P<0.05) ; the improvement in the intermediate-dose prophylaxis group was better than that in the low-dose prophylaxis group (P<0.05). Compared with on-demand treatment, the FISH score, quality of life score, and SF-36 score significantly improved in both groups (P<0.05), but there was no significant difference between the two groups (P>0.05) . Conclusion: In Chinese adults with severe hemophilia A, low- and intermediate-dose prophylaxis can significantly reduce bleeding frequency, delay the progression of joint lesions, and improve the quality of life of patients as compared with on-demand treatment. The improvement in clinical bleeding was better with intermediate-dose prophylaxis than low-dose prophylaxis.

[Tracing investigation and analysis of a Clostridium botulinum food poisoning incident in Bayingolin Mongolian Autonomous Prefecture, Xinjiang]

To analyze a suspected case of Clostridium botulinum food poisoning in Bayingolin Mongolian Autonomous Prefecture, Xinjiang and to help validating the diagnosis and providing technical support for clinical treatment. The basic information and clinical manifestations of food poisoning cases were investigated by using the epidemiological method of food safety accidents. The botulinum toxin genes in the samples were detected by real-time PCR and inoculation of KM mouse. The enriched bacteria were further purified and validated. PFGE and cluster analysis were performed on five isolates. Clostridium botulinum type A was detected in two homemade fermented bean samples and stool lavage fluid samples of three patients from enriched samples by toxin test and real-time PCR, and were further validated after isolation of Clostridium botulinum. PFGE showed 100% homology among five isolates. Five isolates of bacteria isolated from the stool lavage fluid of three patients and two homemade fermented bean curd were identified as the same source through PFGE. The cause of this food poisoning cases is food pollution of Clostridium botulinum type A.

DNA-free CRISPR-Cas9 gene editing of wild tetraploid tomato Solanum peruvianum using protoplast regeneration

Wild tomatoes (Solanum peruvianum) are important genomic resources for tomato research and breeding. Development of a foreign DNA-free clustered regularly interspaced short palindromic repeat (CRISPR)-Cas delivery system has potential to mitigate public concern about genetically modified organisms. Here, we established a DNA-free CRISPR-Cas9 genome editing system based on an optimized protoplast regeneration protocol of S. peruvianum, an important resource for tomato introgression breeding. We generated mutants for genes involved in small interfering RNAs biogenesis, RNA-DEPENDENT RNA POLYMERASE 6 (SpRDR6), and SUPPRESSOR OF GENE SILENCING 3 (SpSGS3); pathogen-related peptide precursors, PATHOGENESIS-RELATED PROTEIN-1 (SpPR-1) and PROSYSTEMIN (SpProSys); and fungal resistance (MILDEW RESISTANT LOCUS O, SpMlo1) using diploid or tetraploid protoplasts derived from in vitro-grown shoots. The ploidy level of these regenerants was not affected by PEG-Ca2+-mediated transfection, CRISPR reagents, or the target genes. By karyotyping and whole genome sequencing analysis, we confirmed that CRISPR-Cas9 editing did not introduce chromosomal changes or unintended genome editing sites. All mutated genes in both diploid and tetraploid regenerants were heritable in the next generation. spsgs3 null T0 regenerants and sprdr6 null T1 progeny had wiry, sterile phenotypes in both diploid and tetraploid lines. The sterility of the spsgs3 null mutant was partially rescued, and fruits were obtained by grafting to wild-type (WT) stock and pollination with WT pollen. The resulting seeds contained the mutated alleles. Tomato yellow leaf curl virus proliferated at higher levels in spsgs3 and sprdr6 mutants than in the WT. Therefore, this protoplast regeneration technique should greatly facilitate tomato polyploidization and enable the use of CRISPR-Cas for S. peruvianum domestication and tomato breeding.

Application of Protoplast Regeneration to CRISPR/Cas9 Mutagenesis in Nicotiana tabacum

Protoplast transfection is widely used in plant research to rapidly evaluate RNA degradation, reporter assay, gene expression, subcellular localization, and protein-protein interactions. In order to successfully use protoplast transfection with the newly emerging clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) protein editing platform, high yield of protoplasts, stable transfection efficiency, and reliable regeneration protocols are necessary. The Nicotiana tabacum transient protoplast transfection and regeneration system can effectively obtain target gene mutations in regenerated plants without transgenes and is thus a very attractive technique for evaluating gene editing reagents using CRISPR/Cas-based systems. Here, we describe in detail sterilized seed germination, culture conditions, isolation of Nicotiana tabacum protoplasts from tissue culture explants, construction of a vector containing the Cas protein and sgRNA cassette, highly efficient polyethylene glycol-calcium transient transfection of plasmids delivered into protoplasts, evaluation of mutagenesis efficiency and genotype analysis from protoplasts and regenerated plants, and the regeneration conditions to obtain CRISPR-edited plants from single protoplasts.

Efficient and Economical Targeted Insertion in Plant Genomes via Protoplast Regeneration

Versatile genome editing can be facilitated by the insertion of DNA sequences into specific locations. Current protocols involving CRISPR and Cas proteins rely on low efficiency homology-directed repair or non-homologous end joining with modified double-stranded DNA oligonucleotides as donors. Our simple protocol eliminates the need for expensive equipment, chemical and enzymatic donor DNA modification, or plasmid construction by using polyethylene glycol-calcium to deliver non-modified single-stranded DNA oligonucleotides and CRISPR-Cas9 ribonucleoprotein into protoplasts. Plants regenerated via edited protoplasts achieved targeted insertion frequencies of up to 50% in Nicotiana benthamiana and 13.6% in rapid cycling Brassica oleracea without antibiotic selection. Using a 60 nt donor containing 27 nt in each homologous arm, 6/22 regenerated N. benthamiana plants showed targeted insertions, and one contained a precise insertion of a 6 bp HindIII site. The inserted sequences were transmitted to the next generation and invite the possibility of future exploration of versatile genome editing by targeted DNA insertion in plants.

Protoplasts: From Isolation to CRISPR/Cas Genome Editing Application

In the clustered regulatory interspaced short palindromic repeats (CRISPR)/CRISPR associated protein (Cas) system, protoplasts are not only useful for rapidly validating the mutagenesis efficiency of various RNA-guided endonucleases, promoters, sgRNA designs, or Cas proteins, but can also be a platform for DNA-free gene editing. To date, the latter approach has been applied to numerous crops, particularly those with complex genomes, a long juvenile period, a tendency for heterosis, and/or self-incompatibility. Protoplast regeneration is thus a key step in DNA-free gene editing. In this report, we review the history and some future prospects for protoplast technology, including protoplast transfection, transformation, fusion, regeneration, and current protoplast applications in CRISPR/Cas-based breeding.

Genome Editing and Protoplast Regeneration to Study Plant-Pathogen Interactions in the Model Plant Nicotiana benthamiana

Biotic diseases cause substantial agricultural losses annually, spurring research into plant pathogens and strategies to mitigate them. Nicotiana benthamiana is a commonly used model plant for studying plant-pathogen interactions because it is host to numerous plant pathogens and because many research tools are available for this species. The clustered regularly interspaced short palindromic repeats (CRISPR) system is one of several powerful tools available for targeted gene editing, a crucial strategy for analyzing gene function. Here, we demonstrate the use of various CRISPR-associated (Cas) proteins for gene editing of N. benthamiana protoplasts, including Staphylococcus aureus Cas9 (SaCas9), Streptococcus pyogenes Cas9 (SpCas9), Francisella novicida Cas12a (FnCas12a), and nCas9-activation-induced cytidine deaminase (nCas9-Target-AID). We successfully mutated Phytoene Desaturase (PDS) and Ethylene Receptor 1 (ETR1) and the disease-associated genes RNA-Dependent RNA Polymerase 6 (RDR6), and Suppressor of Gene Silencing 3 (SGS3), and confirmed that the mutated alleles were transmitted to progeny. sgs3 mutants showed the expected phenotype, including absence of trans-acting siRNA3 (TAS3) siRNA and abundant expression of the GFP reporter. Progeny of both sgs3 and rdr6 null mutants were sterile. Our analysis of the phenotypes of the regenerated progeny indicated that except for the predicted phenotypes, they grew normally, with no unexpected traits. These results confirmed the utility of gene editing followed by protoplast regeneration in N. benthamiana. We also developed a method for in vitro flowering and seed production in N. benthamiana, allowing the regenerants to produce progeny in vitro without environmental constraints.

[Suprapubic-assisted laparoendoscopic single-site surgery in nephroureterectomy A case series of 4 patients]

Objective: To evaluate the feasibility and clinical value of suprapubic-assisted laparoendoscopic single-site surgery (SA-LESS) in nephroureterectomy using method of transvaginal natural orifice specimen extraction (NOSE) (SA-LESS+TV-NOSE NU). Methods: Four patients (three cases of renal pelvic carcinoma and one case of ureteral carcinoma) undergoing SA-LESS+TV-NOSE NU were enrolled between April 2015 and January 2016. After general anesthesia, the patients were placed in the lithotomy position with the affected side elevated by 60°. Two trocars were inserted at the medial margin of umbilicus, and the third one was inserted into abdominal cavity at the superior margin of pubic symphysis. The operation was performed under a direct vision with a 5.4 mm 0° flexible-tip laparoscope. Firstly, the distal ureter was isolated completely and blocked by a Hem-O-lok clip. Then, the laparoscopic nephrectomy was performed according to the standard method. Finally, the bladder cuff excision was executed and the incision was sutured. The intact specimen was placed inside a homemade bag and removed through the incision at posterior vaginal fornix. Results: All the procedures were successfully performed. The median operative time was 150 (range: 120 to 210) minutes, and the median estimated blood loss was 180 (range: 80 to 350) ml. No major perioperative complications occurred. The mean visual analogue score (VAS) of 24 hours and 48 hours after operation were 3.25 (range: 2 to 5) and 2.25 (range: 2 to 3). All the patients resumed ambulation on postoperative day 1. Pelvic drainage tube was removed on postoperative day 2-4. On postoperative day 7, urethral catheter was removed. The patients were discharged on postoperative day 7-9. During the follow-up of 20-29 months, the patient recovered well with no case of incisional hernia and pelvic, abdominal infections. The vaginal fornix incision healed well, and the umbilical and suprapubic puncture scars were not obvious. All the patients completed the patient-assessed acromegaly symptom questionnaire PASQ. The average PSAQ score of 3 months after surgery was 34.5. Three of them restarted their sex lives, with an average female sexual function index score of 16.0, which was not significantly different with that of preoperation (15.6). There was no tumor recurrence, metastasis and implantation in all cases. Conclusion: SA-LESS+TV-NOSE NU is safe and feasible for upper tract urothelial carcinoma with faster postoperative recovery, less pain, shorter hospitalization time, better cosmetic results, and does not cause negative effect on the female sexual function.

[Predictive and prognostic value of monitoring lymphocyte subsets in peripheral blood before and after chemotherapy in patients with metastatic breast cancer]

OBJECTIVE

To detect the proportion of lymphocyte subsets in peripheral blood of the advanced breast cancer patients before and after chemotherapy with docetaxel and thiotepa, as well as the association between the proportion of peripheral blood lymphocyte subsets with the response rate and prognosis.

METHODS

The proportions of lymphocyte subsets (CD3+ T cell, CD3+/CD4+ T cell, CD3+/CD8+ T cell, CD3-/CD16+56+ NK cell, CD3+/CD16+56+ T cell, CD19+ B cell, CD4+/CD25+ T cell, CD8+/CD28- T cell, CD8+/CD28+ T cell) in the peripheral blood of 86 patients were analyzed with flowcytometry before and after chemotherapy. The result was analyzed in combination with clinicopathological data.

RESULTS

The proportion of regulatory T cells (Treg) after chemotherapy in the disease control patients decreased significantly compared with that of the progressive patients (P=0.034). The difference of the proportions of Treg before and after chemotherapy affected significantly the overall survival (OS). The OS of the patients with decreased proportion of Treg was significantly longer than that of the patients with increased proportion of Treg, which was 23.5 and 9.4 months respectively (P<0.05).

CONCLUSION

The patients with decreased proportion of Treg after chemotherapy had higher response rate and better survival benefit.

IMM-H004, a novel coumarin derivative compound, protects against amyloid beta-induced neurotoxicity through a mitochondrial-dependent pathway

We have investigated the effect of IMM-H004 (7-hydroxy-5-methoxy-4-methyl-3-(4-methylpiperazin-1-yl)-2H-chromen-2-one), a coumarin derivative, on the amyloid beta (Aβ)-induced neurotoxicity in primary culture cortical neurons and pheochromocytoma (PC12) cells. Our results showed that treatment with IMM-H004 markedly reduced the number of apoptotic cells after exposure to Aβ25-35 or Aβ1-42, determined by MTT, TUNEL staining and Flow cytometry. Further study indicated that IMM-H004 significantly inhibited Aβ-induced cytotoxicity and apoptosis by reversing Aβ-induced mitochondrial dysfunction, including MMP (mitochondrial membrane potential) decrease, reactive oxygen species production, and mitochondrial release of cytochrome c. IMM-H004 can regulate the interaction between Bax and Bcl-2, decreased levels of p53 and active caspase-3 protein induced by Aβ25-35. Furthermore, IMM-H004 also reduced translocation of AIF (apoptosis-inducing factor) induced by Aβ25-35. These results demonstrated that IMM-H004 was capable of protecting neuronal cells from Aβ-induced degeneration through a mitochondrial-dependent apoptotic pathway. The results of this study lend further credence to the notion that IMM-H004 is a 'multipotent therapeutic agrent' that reduces toxic levels of brain Aβ, and holds the potential to protect neuronal mitochondrial function in Alzheimer's disease.

HLA-B*9518 allele identified in the Chinese population

We report here a novel HLA-B*9518 allele by sequence-based typing in the Chinese population. The new B*9518 is identical to B*150101 with an exception of one base substitution at position 19 of exon 3 where a 'G' change to 'T' resulting in codon 97 changed from AGG (Arg) to ATG (Met).

Chemokine receptor CXCR3 expression in inflammatory bowel disease

CD4+ T lymphocytes in the lamina propria (LP) of the gut play a central role in the immune response in inflammatory bowel disease (IBD). CXCR3 is a chemokine receptor expressed on activated T lymphocytes, and a key component for the recruitment of T helper (Th1) effector cells to the site of inflammation. To determine if CXCR3 is involved in localization of T cells to the gut in IBD patients, we investigated the expression of CXCR3 on CD4+ T lymphocytes in the LP and in the submucosa of resection specimens from 51 IBD patients and 15 control patients. Positive cells were microscopically scored using a semiquantitative analysis on a five-point scale. We found that CD4+ T cells, CXCR3+ cells, and CD4+CXCR3+ T cells in the LP were slightly increased in both IBD groups compared with control non-IBD specimens. In addition, CD4+ and CXCR3+ cells in the submucosa were significant increased in the CD group compared with the control group. CD4+ and CXCR3+ expression was not statistically different between CD and UC. Flow cytometry was used to analyze the percentage of CXCR3+ cells within the CD4+ T-cell population isolated from biopsy specimens and peripheral blood from IBD patients and control patients. There was no difference in the percentage of CD4+CXCR3+ cells between the different groups in the gut as well as in the circulation. These results suggest that CD4+CXCR3+ T cells migrate to the normal and inflamed intestinal mucosa, indicating a role in maintaining normal gut homeostasis. The selective expression of CXCR3+ cells in the submucosa of CD patients might also indicate that these cells play a role in inflammation.

[Alzheimer-like protein phosphatase deficiency leads to abnormal phosphorylation and accumulation of neurofilaments]

OBJECTIVE

To explore the effect of Alzheimer-like protein phosphatase deficiency on neurofilament phosphorylation.

METHODS

Cell culture, light microscopy, immunocytochemistry and biochemistry techniques were used to make a phosphatase deficient cell model, to detect cell morphology, neurofilament phosphorylation and distribution, cell viability and activity.

RESULTS

Non-phosphorylated neurofilament recognized by SMI32 was detected both in cell body and cell processes, it was extremely enriched in cell bodies; Phosphorylated neurofilament bound to SMI34 was mainly determined in cell processes and cell surface. After treatment with okadaic acid (OA), non-phosphorylation-dependent antibodies SMI32 staining was significantly decreased in the cell body, whereas phosphorylated neurofilament reacted with SMI34 was strikingly increased in immunocytochemistry and Western blot, and prominently accumulated to the same cell location. Accompanied with hyper-phosphorylation and accumulation of neurofilament, dose dependent cell toxicity was observed by okadaic acid treatment.

CONCLUSION

Deficiency in protein phosphatase induces in neuroblastoma cell line, neurofilament phosphorylation and accumulation, which is involved in Alzheimer neurofibrillary degeneration.

[Thermal decomposition kinetics of ribavirin and its stability]

AIM

To study Thermal stabilities and thermal decomposition process of ribavirin and establish thermal decomposition kinetics equation.

METHODS

Thermal weight loss curve was obtained by thermogravimetry balance. Thermal decomposition function mode was also determined by Achar differential method and Coats-Redfern integral method.

RESULTS

Thermal decomposition kinetics parameters and kinetics compensation parameters were calculated from thermogravimetry-differential thermogravimetry data. Activation energy deduced by extrapolation under heating rate of 0 degree C.min-1 was 188.04 kJ.mol-1. Thermal decomposition kinetics function expression was d alpha/dt = Ae [formula: see text] (1 - alpha)2 and the mathematic expression of the kinetic compensation effect is found to be InA = 0.2264 Ea - 5.4458.

CONCLUSION

Ribavirin has high thermal stability because of its high thermal decomposition activation energy. The thermal decomposition activation of capsule is little lower than that of material, which indicates no evident difference in thermal stability for capsules and material.