[Research on the framework of biosafety standards for pathogenic microbial laboratories].

Developing and implementing biosafety standards for pathogenic microbiology laboratories is essential to achieving scientific, efficient, and standardized management and operation. This article analyzes the current standardization construction in biosafety in pathogenic microbiology laboratories domestically and internationally. It proposes a framework for the biosafety standard system of pathogenic microbiology laboratories, which mainly includes four parts: basic standards, management standards, technical standards, and industry applications. It provides a reference for the standardization work of pathogenic microbiology laboratories and helps to standardize the biosafety industry in China.

A clinical study of ultrasonic localization-assisted combined transplantation of a bilateral anterolateral thigh perforator flap for the repair of large-area skin and soft tissue defects of the extremities.

OBJECTIVE: The aim of this study was to investigate the clinical efficacy of the combined transplantation of a bilateral anterolateral thigh perforator (ALTP) flap for the repair of large-area skin and soft tissue defects of the extremities. PATIENTS AND METHODS: Twelve patients who had received bilateral ALTP flap reconstructions for large-area skin and soft tissue defects of the extremities were retrospectively analyzed. The areas of the skin and soft tissue defects were measured preoperatively (18.0×11.0 ‒ 38.0×15.0 cm2). The wounds were on the forearm, elbow, upper arm, foot, and lower leg. Color Duplex Sonography (CDS) was used to localize the site where the perforator artery of the bilateral thighs penetrated the deep fascia. The selected area was evaluated according to the number of perforating branches and the range of supply. The flap areas and repairable range were further evaluated according to the number of perforating branches detected during the operation to determine whether to retain the deep fascia. It is important to design and adjust the anastomosis of the vascular pedicle according to the specific situation on transfer of the flap to the recipient site. The donor sites of all the patients in the study were closed in the first stage. The amount of bleeding and the blood supply to the flap after vascular anastomosis were evaluated during the operation. The postoperative survival of the flap and complications, such as bleeding, infection, and arteriovenous crisis, were closely monitored. All patients were followed-up at one, three, and six months after surgery to assess their satisfaction with the appearance of the flap transplantation and the recovery of limb function. RESULTS: The bilateral ATLP flaps survived successfully in all 12 cases and all donor sites were closed in the first stage. No post-surgery complications, including hematoma, wound dehiscence, and infection, were observed at the donor sites, resulting in high patient satisfaction. CONCLUSIONS: Combined transplantation of bilateral ALTP flaps can repair large-area skin and soft tissue defects in one stage, which not only reduces the number of operations and hospitalization costs but also reduces the damage to the limbs caused by the cutting of large-area flaps from only one side. The accuracy of the surgery was improved by ultrasound-assisted localization. In summary, combined transplantation of bilateral ALTP is a rational yet effective way to repair large-area skin and soft tissue defects of the extremities.

Characteristics and surgical treatment of recurrence melanoma of the foot: a case report and brief literature review.

OBJECTIVE: Despite advances in plastic and reconstructive surgery, repairing soft tissue defects of the foot remains a complex surgical challenge when conventional methods cannot cover defects. We presented a case in which a free flap was used for reconstruction and reviewed the literature. PATIENTS AND METHODS: A 75-year-old woman with an acral melanoma history had a large exophytic mass on her right foot. Using PubMed, we found that reconstructive options in the literature include local flaps, fascial flaps, muscle flaps, and free flaps. RESULTS: Melanoma recurred four times at the same site after complete excision of the compound nevi in the present case. Melan A, Vimentin (+), S-100 (+), and HMB-45 positivity were found in immunohistochemical staining and increased Ki-67 proliferation. The defects in soft tissue are repaired using a free anterolateral thigh perforator flap. No complications were raised in the patient. CONCLUSIONS: Foot melanoma is difficult to be resected because it necessitates a wide excision, which can result in large defects. The free flap, in our experience, can easily be performed while preserving function and improving cosmesis. This flap is an appealing option for concealing defects in the distal extremities.

[Analysis of pregnancy outcome after fertility-preserving treatment among women with atypical endometrial hyperplasia or endometrial carcinoma].

Objective: To analyze the pregnancy outcome, influencing factors and recurrence of fertility-preserving therapy for women with atypical endometrial hyperplasia (AEH) or endometrial carcinoma (EC). Methods: The multi-center retrospective study included 107 women with AEH or EC for fertility-preserving therapy in 10 hospitals from January 1st, 2009 to December 31st, 2018. The clinical pregnancy rate, live birth rate and recurrence of 66 patients with urgent child-bearing requirements after fertility-preserving treatment were analyzed. Results: (1) Among the 66 AEH and EC women with urgent child bearing requirements, 24 women chose spontaneous pregnancy, the clinical pregnancy rate was 54.2% (13/24) and the live birth rate was 41.7% (10/24), the median time from fertility-preserving therapy withdrawal to clinical pregnancy was 5.5 months. Forty-two women chose assisted reproductive technology (ART), the clinical pregnancy rate was 59.5% (25/42) and the live birth rate was 35.7% (15/42), the median time from fertility-preserving therapy withdrawal to clinical pregnancy was 19.5 months. The time from fertility-preserving therapy withdrawal to pregnancy in women receiving ART was significantly longer than that in women with spontaneous pregnancy (P=0.048). (2) Age and intrauterine adhesions were independent factors affecting the clinical pregnancy rate (P<0.05). (3) Among 107 patients with AEH or EC, the recurrence rate was 27.1% (29/107). Among the 42 cases who chose ART, 9 of them recurred before ART treatment, who received the fertility-preserving therapy again and then ART treatment, 8 women got clinical pregnancy,5 of them delivered at least a live birth. Conclusions: Women with AEH or EC could achieved satisfactory clinical pregnancy rate and live birth rate after fertility-preserving therapy. Age and intrauterine adhesions are independent factors affecting clinical pregnancy rate. The women with recurrent AEH or EC could be treated with fertility-preserving therapy again and get a satisfactory pregnancy outcome.

Selective deletion of Pten in theca-interstitial cells leads to androgen excess and ovarian dysfunction in mice.

Theca cell-selective Pten mutation (tPtenMT) in mice resulted in increases in PDK1 and Akt phosphorylation, indicating an over-activation of PI3K signaling in the ovaries. These mice displayed elevated androgen levels, ovary enlargement, antral follicle accumulation, early fertility loss and increased expression of Lhcgr and genes that are crucial to androgenesis. These abnormalities were partially reversed by treatments of PI3K or Akt inhibitor. LH actions in Pten deficient theca cells were potentiated. The phosphorylation of Foxo1 was increased, while the binding of Foxo1 to forkhead response elements in the Lhcgr promoter was reduced in tPtenMT theca cells, implying a mechanism by which PI3K/Akt-induced upregulation of Lhcgr in theca cells might be mediated by reducing the inhibitory effect of Foxo1 on the Lhcgr promoter. The phenotype of tPtenMT females is reminiscent of human PCOS and suggests that dysregulated PI3K cascade in theca cells may be involved in certain types of PCOS pathogenesis.

Controlling multiple filaments by relativistic optical vortex beams in plasmas.

Filamentation dynamics of relativistic optical vortex beams (OVBs) propagating in underdense plasma is investigated. It is shown that OVBs with finite orbital angular momentum (OAM) exhibit much more robust propagation behavior than the standard Gaussian beam. In fact, the growth rate of the azimuthal modulational instability decreases rapidly with increase of the OVB topological charge. Thus, relativistic OVBs can maintain their profiles for significantly longer distances in an underdense plasma before filamentation occurs. It is also found that an OVB would then break up into regular filament patterns due to conservation of the OAM, in contrast to a Gaussian laser beam, which in general experiences random filamentation.

Practices and thinking of laboratory detection in the aid to West Africa to fight against Ebola.

BACKGROUND: The outbreak of Ebola virus disease in West Africa has brought great disaster to the people's health in affected countries. China dispatched first group of public health experts and medical staff to Sierra Leone in September 2014 to fight Ebola. METHODS: To systematically collect huge amount of primary data, and to make analysis, draw conclusions and lessons in terms of six aspects, respectively as training before departure, local disease information, track of epidemic situation, transformation of temporary laboratory, detection of Ebola virus samples as well as assessment through single blind test. RESULTS: 1) Our team has launched preparatory works in advance before going to Sierra Leone. 2) Malaria is the country's severest infectious disease. 3) Observation centers were overcrowded with large number of suspected cases being inspected, implying high risk of nosocomial infection. 4) A BSL-II laboratory with 3 work areas and 2 buffer areas was built, achieving several major functions within 6 days. 5) Confirmed by South African Raqqa laboratory, our detection accuracy reached 100%. 6) At one week before return, the daily average sample amount of our team reached 66 cases and our detection capability was equivalent to that of USA. CONCLUSIONS: Successful experience from fighting against Ebola in Sierra Leone could be summarized as: 1) Optimized processes and scientific security measures are prerequisite to improving the detection ability. 2) The close collaboration between laboratory and observation center has created a new model of China's foreign aid. 3) Comprehensive information investigation and training lay a solid foundation for the successful completion of tasks.

Molecular dynamics simulation of the interfacial structure of [C(n)mim][PF6] adsorbed on a graphite surface: effects of temperature and alkyl chain length.

The structures and diffusion behaviors of a series of ionic liquids [C(n)mim][PF(6)] (n = 1, 4, 8 and 12) on a graphite surface have been investigated by means of molecular dynamics simulation. It was found that three or four ordering layers of ionic liquids were formed near the graphite surface, and this layering structure was stable over the temperature range investigated. At the liquid/vacuum interface, the ionic liquid with a butyl chain had a monolayer ordering surface, while [C(8)mim][PF(6)] and [C(12)mim][PF(6)] exhibited a bilayer ordering with a polar domain sandwiched between two orientational nonpolar domains. More impressively, the simulated results showed that for the ionic liquids with alkyl chains longer than C(4), the adjacent alkyl chains in the whole film tended to be parallel to each other, with the imidazolium rings packed closely together. This indicated that the ionic liquids have a better regulated short-range structure than was previously expected. It was also found that both in the bottom layer and in the bulk region, the diffusion of the alkyl chains was much faster than that of the polar groups. However, as the alkyl chain length increased, the charge delocalization in the cation and the enhanced van der Waals interaction between the nonpolar groups contributed by reducing this difference in the diffusivity of major groups.

A rare case of the coexistence of ovarian clear cell carcinoma, mucinous cystadenoma, and endometriosis in the same ovary.

Clear cell carcinomas and endometrioid carcinomas are associated with endometriosis. The association of clear cell carcinomas with mucinous lesions has only been reported infrequently, and with mucinous cystadenoma has been rarely reported. This is the second reported case of the coexistence of ovarian clear cell carcinoma, mucinous cystadenoma, and endometriosis in the same ovary. A 57-year-old woman presented with lower abdominal pain for three weeks. Ultrasonography revealed a 16 x 14 x 10 cm mass in the left ovary with solid and cystic components. Hysterectomy and bilateral salpingo-oophorectomy were performed. Histopathological examination of the left ovary revealed the presence of clear cell carcinoma, mucinous cystadenoma, and endometriosis. Continuity between the areas of mucinous epithelium and clear cell carcinoma were noted; this may suggest that clear cell carcinoma may arise from endometriosis or mucinous cystic tumors.

An outbreak of Salmonella Paratyphi A in a boarding school: a community-acquired enteric fever and carriage investigation.

Salmonella Paratyphi A (SPA) is rapidly becoming a common cause of enteric fever in South East Asia. A large outbreak of SPA occurred in a boarding middle school in China in 2004. There were 394 suspected cases; 95·5% were students. The highest incidence was in the youngest children (7th grade). Forty-four of 151 (29%) blood cultures and 4/54 (7·4%) rectal swabs were positive for SPA; three were from kitchen workers. The geometric mean levels of serum IgG anti-lipopolysaccharide (anti-LPS) from patients was higher than from healthy individuals [35·25 vs. 5·20 ELISA units (EU), P<0·001]. A kitchen worker with a positive rectal swab, negative blood culture and a high level of serum IgG anti-LPS (529·65 EU), was identified as a possible SPA carrier. No SPA was isolated from water or food samples. A survey of students' habits indicated drinking unboiled water as being the main reason for contracting the disease. Hand washing was the second most important factor. A food handler with possible SPA carriage could also have been a risk factor. Attention to maintaining a safe water supply, enhancing food-handler hygiene and proper hand washing can help to prevent similar outbreaks in the future.

A genome-wide scan reveals candidate susceptibility loci for pig hernias in an intercross between White Duroc and Erhualian.

Pig scrotal/inguinal and umbilical hernias are the most prevalent congenital disorders in pigs and often cause animal welfare problems and economic loss. To identify susceptibility loci for these traits, a genome-wide scan with 194 microsatellite markers covering the pig genome was performed in a White Duroc x Erhualian resource population with 23 scrotal/inguinal F(2) animals, 50 umbilical F(2) animals, and their unaffected siblings. A sex-average linkage map with a total length of 2,350.3 cM and an average marker interval of 12.84 cM was constructed. Both nonparametric genome-wide linkage (NPL) analysis and transmission disequilibrium test (TDT) were implemented to detect closely linked markers. The NPL analysis revealed 11 chromosomal regions on SSC1, 2, 3, 6, 7, 8, 10, and 11 for umbilical hernia and 5 regions on SSC2, 4, 8, 13, and 16 for scrotal/inguinal hernia, whereas the TDT test identified susceptibility loci for umbilical hernia on SSC1, 2, 4, 7, 10, 13, 14, and 15 and for scrotal/inguinal hernias on SSC2, 8, 10, and 18. The most promising loci were SWR1928 on SSC7 and SW830 on SSC10 for umbilical hernia, and SW933 on SSC8 for scrotal hernia, which were consistently detected by both NPL and TDT. Several previously reported chromosomal regions for scrotal/inguinal hernia were confirmed, and new evidence for linkage with this pig defect was found. Moreover, susceptibility loci for pig umbilical hernia were detected for the first time.

Genome-wide identification of quantitative trait loci for pork temperature, pH decline, and glycolytic potential in a large-scale White Duroc x Chinese Erhualian resource population.

The pH values and temperatures at 45 min, and 3, 9, 15, and 24 h postmortem in the LM and semimembranosus muscle (SM) and glycolytic potential in LM were measured in 1,030 F(2) animals from a White Duroc x Erhualian resource population. A whole genome scan was performed with 183 microsatellites covering 19 porcine chromosomes to detect QTL for traits measured. A total of 73 QTL have been identified, including 1% genome-wise significant QTL for 24-h pH in LM and SM on SSC 15, and for glycolytic potential, total glycogen, and residual glycogen on SSC3, 6, and 7. Six 5% genome-wise significant QTL were detected for 9-h pH in SM on SSC3, pH decline from 3/9 h to 24 h in SM on SSC7, glycolytic potential on SSC1, and total glycogen on SSC1 and 6. This study confirmed QTL previously identified for pH except those on SSC1, 11, 12, and X, and found 11 new 5% genome-wise significant QTL for glycogen-related traits. This is the first time to report QTL for pH development during post-slaughter and for glycolytic potential at 5% genome-wise significance level. In addition, the observed different QTL for pH and pH decline at different times show that causal genes for pH postmortem play distinct roles at specific stages, in specific muscles, or both. These results provide a starting point for fine mapping of QTL for the traits measured and improve the understanding of the genetic basis of pH metabolism after slaughter.

Renoprotective effects of combination of angiotensin converting enzyme inhibitor with mycophenolate mofetil in diabetic rats.

OBJECTIVE AND DESIGN: Previously it was shown that blocking of the renin-angiotensin system (RAS) by angiotensin converting enzyme (ACE) inhibitors, or suppression of inflammatory responses by immunosuppressive drugs such as mycophenolate mofetil (MMF) could attenuate renal injury in diabetic rats. Whether RAS blockade combined with an immunosuppressive drug provides superior renoprotection against diabetic nephropathy has not been clearly delineated. MATERIALS: Diabetes was induced by injection of streptozotocin after uninephrectomy. TREATMENT: Rats were randomly separated into five groups: control, diabetes, diabetes treated with enalapril (an ACE inhibitor, 10 mg/kg/d by gastric gavage), diabetes treated with MMF (10 mg/kg/d by gastric gavage), or diabetes treated with a combination of both agents and were followed for 8 weeks. METHODS: 24 h urinary albumin excretion rate (AER) was determined, renal injury was evaluated, immunohistochemistry for ED-1 macrophage marker, intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1) were performed, and expression of transforming growth factor (TGF)-beta1 protein was determined by Western blotting analysis. RESULTS: Diabetes was associated with a considerable increase in AER. Both enalapril and MMF retarded the increase in albuminuria, which was nearly completely abrogated by combination therapy. Increased glomerular volume and tubulointerstitial injury index in diabetic rats was attenuated by treatment with either enalapril or MMF and further reduced by the combination of the two. Elevated malondialdehyde levels in renal tissue were reduced by enalapril or MMF and, more effectively, by combined enalapril with MMF. Renal overexpression of ICAM-1 was not retarded by enalapril and attenuated by MMF or combined enalapril with MMF. Combination therapy was associated with a superior suppression of diabetes-induced macrophage recruitment and overexpression of MCP-1 and TGFbeta1 compared to either monotherapy in renal tissue. CONCLUSION: The combination of enalapril and MMF confers superiority over monotherapy in renoprotection, a mechanism which may be at least partly correlated with synergistic suppression of increased macrophage recruitment and overexpression of MCP-1 and TGF-beta1 in renal tissue in diabetic rats.

Structure-based discovery of small molecule inhibitors targeted to protein tyrosine phosphatase 1B.

Protein tyrosine phosphatases (PTPases) are involved in the control of tyrosine phosphorylation levels in the cell and are believed to be crucial for the regulation of a multitude of cellular functions. A detailed understanding of the role played by PTPases in various signaling pathways has not yet been achieved, and potent and selective PTPase inhibitors are essential in the quest to determine the functionality of individual PTPases. Using the DOCK methodology, we have carried out a structure-based, computer-assisted search of an available chemical database in order to identify low molecular weight, nonpeptidic PTP1B inhibitors. We have identified several organic molecules that not only possess inhibitory activity against PTP1B but which also display significant selectivity for PTP1B. This indicates that although structural features important for pTyr recognition are conserved among different PTPases, it is possible to generate selective inhibitors targeted primarily to the catalytic site. Kinetic analysis and molecular modeling experiments suggest that the PTP1B active site possesses significant plasticity such that substituted and extended aromatic systems can be accommodated. The newly identified molecules provide a molecular framework upon which therapeutically useful compounds can ultimately be based, and systematic optimization of these lead compounds is likely to further enhance their potency and selectivity.

Pharmacokinetics of four 5-FU preparations administered rectally to rats and rabbits.

AIM: To compare the pharmacokinetic characteristics of four preparations of fluorouracil (5-FU) administered rectally using a rat model. METHODS: Concentrations of 5-FU were measured in plasma, the rectal wall and mesentery lymph tissues of rats and rabbits by high performance liquid chromatography. Differences between the main pharmacokinetic parameters were compared by statistical analysis. RESULTS: The 5-FU concentrations in the rectal wall and mesenteric lymph tissues were significantly higher than the concentration in blood following rectal administration for all four of the preparations (P < 0.01). The drug level in the rectal wall was higher in the animals received delivery of an emulsion, compared to those who received delivery as a suppository (P < 0.05). Moreover, the animals who received a lipophil-based suppository had lower plasma level of drug than those who received a hydrophil-based suppository, and the animals who received the simple (o/w) emulsion had lower plasma level than those who received the complex (w/o/w) emulsion. The differences found in the rat model were confirmed in rabbits (P < 0.01). CONCLUSION: The lipophil-based suppository and the simple emulsion of 5-FU might be more suitable for rectal administration for treatment of rectal cancers.

[Diphasic regulatory effect of lishen injection on sex hormones in senile female patients with coronary heart disease of kidney deficiency type].

Effects of Lishen injection on serum estradiol (E2), testosterone (T) and the E2/T ratio in 30 cases of postmenopausal patients with coronary heart disease and of Kidney Deficiency type were observed. Results showed that: (1) Serum E2 and the E2/T ratio were lower (P < 0.01) in the group of Kidney-Yin Deficiency type and higher (P < 0.01) in the group of Kidney-Yang Deficiency type as compared with normal control. (2) After treatment with Lishen injection the levels of serum E2 and the E2/T ratio were elevated in the former (P < 0.01) and lowered in the later (P < 0.01). Both were approaching to normal level (P > 0.05). (3) The levels of T in both groups were unaffected (P > 0.05) before and after treatment. These results suggested the imbalance of Kidney-Yin and Kidney-Yang is related to the disturbance of sex hormones and Lishen injection could not only regulate the Kidney-Yin and Kidney-Yang, improve the symptoms of Kidney Deficiency, but also could convert the abnormal change of sex hormone, it has a good diphasic regulatory effect on E2, and is beneficial on balance of sex hormones of both sex in the inner environment of human body.

Myoglobin-NO at low pH: free four-coordinated heme in the protein pocket.

In either sperm whale or horse heart myoglobin, binding of NO and lowering of solution pH work together to weaken, and ultimately break, the bond between iron and the proximal histidine. This is reminiscent of the reaction observed at neutral pH in the case of guanylate cyclase, the heme enzyme that catalyzes the conversion of GTP to cGMP. Bond breaking is characterized by a spectral change from a nine-line to a three-line ESR signal and accompanied by a shift from 420 to 387 nm in the UV-vis spectrum of the Soret band maximum. Analysis of the pH-dependent spectral changes shows that they are reversible, at least within a few hours, that the transition is cooperative, involving six protons during pH lowering but only two as it is raised, and that the pK is about 4.7. Different proteins exhibit different pK values, which are generally lower than that for "chelated" protoheme. The pK differences reflect the extra bond stability afforded by the protein structure. Investigations of thermal and photochemical NO displacement by CO suggest that the local pocket around the ligand, although significantly altered (according to circular dichroism investigations), nonetheless still imposes a barrier against the outward diffusion of ligand into the solvent. Nanosecond and picosecond flash photolysis shows that in proteins at low pH there is an extremely efficient geminate recombination of the ligand with the four-coordinated species through a single-exponential process. This occurs to a significantly larger extent than for the case of NO-"chelated" protoheme (where no distal barrier for ligand is present). At neutral pH, when the proximal histidine bond is intact, the geminate recombination for NO takes longer and displays multiexponential kinetics. Altogether, these results suggest that, even though distal effects probably also play a role, proximal effects make an important contribution in modulating ligand-iron bond formation.

Comparative study on antigenicity and immunogenicity of 26-28 kDa antigen and recombinant Sj26 (RSj26) of Schistosoma japonicum.

This paper reports a comparison of the recombinant Sj26 (rSj26) antigen derived from the Philippine strain and the 26-28 kDa antigen isolated and purified from the Chinese strain of Schistosoma japonicum with respect to their antigenicity and immunogenicity. The results showed that there were obvious cross reactions between rSj26 and 26-28 kDa antigen when rSj26 antigen was tested against specific antibodies in sera of mice infected with the Chinese strain of S. japonicum or the 26-28 kDa antigen was tested against specific anti-rSj26 antibodies by ELISA, IFA and Western blotting. Both the 26-28 kDa and the rSj26 antigen had weak cross reactions with SEA antigen. The worm reduction rate after challenging with Chinese strain cercariae in mice immunized with rSj26 was 26-32%, similar to that in mice immunized with 26-28 kDa antigen. It is suggested that rSj26 antigen can induce a certain level of specific protective immunity in the host against infection by the Chinese strain of S. japonicum cercariae.

[Comparative study on antigenicity and immunogenicity of the 24-26 kDa antigen and the recombinant Sj26 antigen of Schistosoma japonicum].

This paper reports on the comparison of the recombinant Sj26 (rSj26) antigen originated from the Philippine strain and 24-26 kDa antigen isolated and purified from Chinese mainland strain of S. japonicum for their antigenicity and immunogenicity. The results showed that there were obvious cross reactions between rSj26 and 24-26 kDa antigen when rSj26 antigen was tested against specific antibodies in sera from mice infected with the mainland strain of S. japonicum or 24-26 kDa antigen was tested against specific anti-rSj26 antibodies by ELISA, IFA and Western blotting etc. Both of 24-26 kDa and rSj26 antigen had weak cross reaction with SEA antigen. The worm reduction rate after challenging with mainland strain cercariae in mice immunized with rSj26 was 26-32%, similar to that in mice immunized with 24-26 kDa antigen. It is suggested that rSj26 antigen can induce certain level of specific protective immunity to protect the host against infection by Chinese strain of S. japonicum cercaciae.