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The high host genetic background of tissue biopsies hinders the application of shotgun metagenomic sequencing in characterizing the tissue microbiota. We proposed an optimized method that removed host DNA from colon biopsies and examined the effect on metagenomic analysis. Human or mouse colon biopsies were divided into two groups, with one group undergoing host DNA depletion while the other serving as the control. Host DNAs were removed through differential lysis of mammalian and bacterial cells before sequencing. The impact of host DNA depletion on microbiota was compared based on phylogenetic diversity analyses and regression analyses. Removing host DNA enhanced bacterial sequencing depth and improved species discovery, increasing bacterial reads by 2.46 ± 0.20 fold while reducing host reads by 6.80% ± 1.06%. Moreover, 3.40 times more of bacterial species were detected after host DNA depletion. This was confirmed from mouse colon tissues, increasing bacterial reads by 5.46 ± 0.42 fold while decreasing host reads by 10.2% ± 0.83%. Similarly, significantly more species were detected in mouse colon tissue upon host DNA depletion (P0.001). Furthermore, an increased microbial richness was evident in the host DNA-depleted samples compared to non-depleted controls in human colon biopsies and mouse colon tissues (P0.001). Our optimized method of host DNA depletion improved the sensitivity of shotgun metagenomic sequencing in bacterial detection in the biopsy, which may yield a more accurate taxonomic profile of the tissue microbiota and identify bacteria that are important for disease initiation or progression.

Simulating physics with large SU(N) symmetry is one of the unique advantages of Alkaline-earth atoms.Introducing periodical driving modes to the system may provide more rich SU(N) physics that static one could not reach. However, whether the driving modes will break the SU(N) symmetry is still lack of discussions. Here we experimentally study a Floquet engineered degenerate Sr-87 optical lattice clock (OLC) by periodically shaking the lattice. With the help of Rabi spectroscopy, we find that the atoms at different Zeeman sublevels are tuned by the same driven function. Meanwhile, our experimental results suggest that uniform distribution among the sublevels will not change despite the driving. Our experimental demonstrations may pave the way to implementation of FE on tailoring the SU(N) physics in OLC system.

The interference between a sequence of Landau-Zener (LZ) transitions can produce Rabi oscillations(LZROs). This phenomenon is a kind of time-domain Landau-Zener-Stuckelberg-Majorana (LZSM) interference. However, experimental demonstrations of this LZSM interference induced Rabi oscillation are extremely hard due to the short coherence time of the driven quantum system. Here, we study theoretically the time-domain LZSM interference between the clock transition in one-dimensional (1D) Sr-87 optical lattice clock (OLC) system. With the help of both the adiabatic-impulse model and Floquet numerical simulation method, the LZROs with special step-like structure are clearly found both in fast- and slow-passage limit in the real experiment parameter regions. In addition, the dephasing effect caused by the system temperature can be suppressed with destructive interference in the slow-passage limit. Finally, we discuss the possible Bloch-Siegert shift while the pulse time is away from the half-integer and integer periods. Our work provides a clear roadmap to observe the LZROs on the OLC platform.

The diagnostic characters of the genera

Context Ovarian tissue cryopreservation is effective in preserving fertility in cancer patients who have concerns about fertility loss due to cancer treatment. However, ischemia reduces the lifespan of grafts. Microvascular transplantation of cryopreserved whole ovary may allow immediate revascularisation, but the damage incurred during the cryopreservation procedure may cause follicular depletion; hence, preventing chilling injury would help maintain ovarian function. Aim This study was designed to investigate the beneficial effects of antifreeze protein III (AFP III) on rabbit ovary cryopreservation. Methods Ovaries (n = 25) obtained from 5-month-old female rabbits (n = 13) were frozen by slow freezing and vitrification. Cryoprotectant media were supplemented with and without 1 mg/mL of AFP III. The experiment was divided into five groups: fresh control group (F), slow freezing group (S), slow freezing group with AFP III (AFP III-S), vitrification group (V) and vitrification group with AFP III (AFP III-V). All groups of ovaries were examined by histological characteristics analysis, ultrastructural analysis, apoptosis detection and follicle viability test. Key results With slow freezing, the normal rate of change in follicle morphology, density of stromal cells and the survival rate of follicles in the AFP III supplemented group were significantly higher than those in the non-supplemented group, and a lower oocyte apoptotic rate was shown in the AFP III supplemented group. In the vitrification groups, the normal rate of change in follicle morphology and density of stromal cells in the AFP III supplemented group were significantly higher than those in the non-supplemented group, and a lower oocyte apoptotic rate was found in the AFP III supplemented group. But there was no obvious difference in the survival rate of follicles between the two groups. There was also no significant difference in the normal rate of change in follicle morphology, the survival rate of follicles and the apoptotic rate of oocytes between the vitrification and slow freezing groups (P > 0.05), but the density of stromal cells in the vitrification groups was statistically higher than that of the slow freezing group (P

In the present study, we propose a high frequency sensor (HFS) for water holdup measurement in high water-cut oil-in-water flow with low velocity. Through analyzing amplitude-frequency characteristics and phase-frequency characteristics of HFS in different working frequencies using the finite element method, the optimal working frequency of HFS is determined, and the relationship between the phase output of HFS and the water holdup is analyzed. With the designed HFS measurement system, an experiment of vertical upward high water-cut oil-in-water two-phase flow with low velocity is conducted in a 20 mm inner diameter (ID) pipe, through which the relationships among phase output signals of HFS, water-cut and total flow rate are obtained under the dispersed oil-in-water flow (D O/W). In addition, the variations of sensor output for changing water salinity are investigated. The results show that HFS possesses high water holdup measurement resolution which can substantially overcome the limitation that traditional conductance and capacitance method exhibit extremely low resolution in oil-in-water flows with both high water-cut and high water salinity. Based on drift-flux model, water-cut can be predicted with high accuracy.

Purpose: The aim of this study was to determine the impact of analyzing age as a continuous variable on survival outcomes and treatment selection for extranodal nasal-type NK/T-cell lymphoma. Results: The risk of mortality increased with increasing age, without an apparent cutoff point. Patients’ age, as a continuous variable, was independently associated with overall survival after adjustment for covariates. Older early-stage patients were more likely to receive radiotherapy only whereas young-adult advanced-stage patients tended to receive non-anthracycline-based chemotherapy. A decreased risk of mortality with radiotherapy versus chemotherapy only in early-stage patients (HR, 0.347, P < 0.001) or non-anthracycline-based versus anthracycline-based chemotherapy in early-stage (HR, 0.690, P = 0.001) and advanced-stage patients (HR, 0.678, P = 0.045) was maintained in patients of all ages. Conclusions: These findings support making treatment decisions based on disease-related risk factors rather than dichotomized chronological age. Patients and Methods: Data on 2640 patients with extranodal nasal-type NK/T-cell lymphoma from the China Lymphoma Collaborative Group database were analyzed retrospectively. Age as a continuous variable was entered into the Cox regression model using penalized spline analysis to determine the association of age with overall survival (OS) and treatment benefits.

Background/Aims: Transplantation of mesenchymal stem cells (MSCs) has been shown to alleviate dextran sulfate sodium (DSS) -induced colitis through modulation of transforming growth factor β (TGFβ) receptor signaling. However, the exact molecular mechanisms are not known. Methods: Here, we transplanted primary mouse MSCs or injected TGFβ1 into mice with DSS-induced colitis. Cells were purified by flow cytometry. Gene expression was analyzed by RT-qPCR. Results: We found that MSCs significantly alleviated the DSS-induced colitis, and the major sources for TGFβ1 were macrophages that were recruited by MSCs. Specific ablation of macrophages completely abolished the anti-inflammatory effects of MSCs. On the other hand, TGFβ1 administration, without the presence of MSCs, was sufficient to reduce the severity of DSS-induced colitis. Conclusions: Taken together, our data suggest that MSCs transplantation may recruit macrophages to produce TGFβ1, which mitigates the pathology of colitis. Thus, MSCs transplantation appears to be a promising therapy for severe enteritis.

According to the problem of large friction resistance exists between the sealing ring and the cylinder block when the piston cylinder works, the drag reduction technology of bionic concave surface was applied in the sealing ring. By building a drag reduction motion model of sealing ring with concave surface of triangular arrangement, the effect of drag reduction performance decided by concave diameter and piston velocity was studied with the method of numerical simulation. The results show that: when the piston velocity is fixed, the maximum drag reduction rate can be achieved with the concave diameter is 1.5mm, and the maximum drag reduction rate is 15.72%. Meanwhile when the diameter of the concave is fixed, the drag reduction rate increased gradually with the increase of initial speed, the drag reducing effect is best at the speed of 0.6m/s. In the process of piston movement, lubricating oil in concave shakes, and makes the lubricating oil flow to the inside wall of cylinder, which play the role of lubrication, so as to achieve the effect of reducing friction and increasing the movement speed of piston.

According to the problem of bionic shark gill jet can reduce friction on shark surface, a model of bionic jet surface was established based on shark surface was analyzed by measurements, and its numerical simulation was processed by using RNG k-ε turbulence model. The results show that: the gill jet can reduce frictional resistance on shark surface, and the best drag reduction can be got when the speed of main field is 5m/s, furthermore the maximum drag reduction rate can be up to 17.15%. The pressure of jet hole upstream is reduced which due to the barrier to the facing fluid by the jet, so that the pressure resistance of jet surface is reduced as well. Besides, jet fluid is blocked in the boundary layer by mainstream fluid, which caused the fluid velocity of jet hole downstream is reduced, the thickness of boundary layer is increased, and the normal velocity gradient of wall is reduced, so as to achieve the effect of drag reduction.

According to the problem of drag reduction on bionic jet surface, a rectangular jet surface model which is similar to shark branchial shape was built, and numerical simulation was processed by using SST k-ω turbulence model, moreover, influence of jet hole size on the drag reduction performance of jet surface was studied. The results show that: the effect of flow length of rectangular jet hole on the drag reduction is remarkable, with the increase of flow length, fluid friction resistance of the jet surface decreases, the maximum drag reduction rate was 14.38%, and the results of numerical simulation was verified by carrying out experiments. The jet fluid decreases the sweep on the wall of mainstream high speed fluid, which increases the thickness of jet surface boundary layer, thereby reducing the surface friction of the jet hole downstream.

To determine the effects of heat-killed VSL#3 (B. breve, B. longum and B. infantis; L. plantarum, L. bulgaricus, L. casei and L. acidophilus; S. salivarius subsp. thermophilus) therapy in the dextran sulfate sodium (DSS)-induced acute experimental colitis in rats. Acute experimental colitis was induced in rats by 5% DSS and freely drink for seven days. Beginning on Day 8, rats underwent gavage once daily for seven days with heat-killed probiotic VSL#3 (0.6 g/kg/day), colonic damage was evaluated histologically and biochemically seven days after gavage. Expression of inflammatory related mediators (STAT3, P-STAT3) and cytokines (IL-6, IL-23, TGFβ) in colonic tissue were detected. The results revealed that heat-killed and live VSL#3 have identical anti-inflammatory properties by the assessed DAI (disease activity index), colon length, histological tissue and MPO activity. Heat-killed and live VSL#3 results in reduced IL-6, IL-23, TGFβ, STAT3 and P-STAT3 expression in colonic tissue. Heat-killed and live VSL#3 have showed the similar anti-inflammatory activity by inhibiting IL-6/STAT3 pathway in the DSS-induced acute experimental colitis in rats.

The cross-section of yarn in plain woven fabric has always been viewed as an invariable shape by academe. However, with visualization technology, problems in the classical model are exposed based on traditional convex model, and when solving the problems with calculus, the rule of yarn cross-section deformation is found. The results show the diversity of yarn cross-section shape in both one-layer and multi-layer woven fabric, instead of unitarity, especially for warps weaving multi-layer wefts, whose convex cross-section alternates with concave one periodically in length. The results take exception to “invariant cross-section assumption” and have theoretical value and guidance for the real shape of yarns and the simulation of fabric appearance.

Although a series of studies have shown that VSL#3 (L plantarum, L Bulgaricus, L casei and L. acidophilus, B breve, B longum and B infantis and S salivarius subspecies thermophilus) can exert therapeutic effects on colitis, whether heat-killed VSL#3 also can exert similar effects has never been tested. The aim of the study was to investigate whether heat-killed VSL#3 exert therapeutic effects in chronic experimental colitis by inhibiting STAT3 pathway. Chronic experimental colitis was induced by dextran sulfate sodium (DSS) in rats. Rats underwent gavage once daily for seven days with heat-killed VSL#3 (0.6 g/kg/day). The disease activity index (DAI), histological score, colon length and myeloperoxidase (MPO) activity was observed. Expression of inflammatory related mediators (STAT3, P-STAT3) and cytokines (IL-6, IL-23) in colonic tissue were detected. The results showed that live and heat-killed VSL#3 have identical anti-inflammatory effects by the assessed DAI, colon length, histological score and MPO activity. Live and heat-killed VSL#3 results in reduced IL-6, IL-23, STAT3 and P-STAT3 expression in colonic tissue. Heat-killed VSL#3 have showed significant anti-inflammatory effects by suppressing STAT3 pathway.

TNF-α has an important role in the pathogenesis of ulcerative colitis (UC). It seems that anti-TNF-α therapy is beneficial in the treatment of UC. The aim was to assess the effectiveness of Infliximab and Adalimamab with UC compared with con- ventional therapy.The Pubmed and Embase databases were searched for studies investigating the efficacy of infliximab and adalimumab on UC.Infliximab had a statistically significant effects in induction of clinical response (RR = 1.67; 95% CI 1.12 to 2.50) of UC compared with conventional therapy, but those had not a statistically significant effects in clinical remission (RR = 1.63; 95% CI 0.84 to 3.18) and reduction of colectomy rate (RR = 0.54; 95% CI 0.26 to 1.12) of UC. And adalimumab had a statistically significant effects in induction of clinical remission (RR =1.82; 95% CI 1.24 to 2.67) and clinical response (RR =1.36; 95% CI 1.13 to 1.64) of UC compared with conventional therapy.Our meta-analyses suggested that Infliximab had a statistically significant effects in induction of clinical response of UC compared with conventional therapy and adalimumab had a statistically significant effects in induction of clinical remission and clinical response of UC compared with conventional therapy.

Aim Voluntary exercise has been shown to protect against the development of ulcerative colitis, but the mechanism is not fully understood. We hypothesized that prior voluntary exercise would attenuate colonic inflammation and ameliorate clinical symptoms in dextran sulphate sodium (DSS)-induced ulcerative colitis by increasing glucocorticoid production and up-regulating PPAR-γ activity in the colon. Methods Male C57Bl/6J mice were assigned to sedentary, exercise, exercise with PPAR-γ antagonist GW9662 or glucocorticoid synthesis inhibitor metyrapone. Following the completion of the 30 days’ exercise training programme, they were treated with or without 2% DSS in drinking water for 5 days, followed by 5 days of regular water. Results Compared with sedentary mice, exercise mice exhibited improved clinical symptoms (weight loss and diarrhoea) and less inflammation (expression of pro-inflammatory cytokines and histological injury) in response to DSS, whereas these beneficial effects were abolished by both GW9662 and metyrapone treatment. Molecular studies revealed that exercise significantly increased the expression of PPAR-γ, augmented the expression of steroidogenic enzymes (CYP11A1 and CYP11B1) and elevated corticosterone levels in the colon. GW9662 treatment reversed the expression of PPAR-γ without altering the expression of steroidogenic enzymes and corticosterone secretion in the colon, while metyrapone treatment blocked glucocorticoid secretion and abrogated the increase in PPAR-γ expression in the colon. Conclusion These findings suggest that prior voluntary exercise suppresses the expression of pro-inflammatory cytokines in the colon in response to inflammatory challenge by up-regulating glucocorticoid-mediated PPAR-γ activity, contributing to protection against the development of ulcerative colitis.

AIM: To compare the effect of endoscopic variceal ligation (EVL) with that of endoscopic injection sclerotherapy (EIS) in the treatment of patients with esophageal variceal bleeding. METHODS: We performed a systematic literature search of multiple online electronic databases. Meta-analysis was conducted to evaluate risk ratio (RR) and 95% confidence interval (CI) of combined studies for the treatment of patients with esophageal variceal bleeding between EVL and EIS. RESULTS: Fourteen studies comprising 1236 patients were included in the meta-analysis. The rebleeding rate in actively bleeding varices patients in the EVL group was significantly lower than that in the EIS group (RR = 0.68, 95%CI: 0.57-0.81). The variceal eradication rate in actively bleeding varices patients in the EVL group was significantly higher than that in the EIS group (RR = 1.06, 95%CI: 1.01-1.12). There was no significant difference about mortality rate between the EVL group and EIS group (RR = 0.95, 95%CI: 0.77-1.17). The rate of complications in actively bleeding varices patients in the EVL group was significantly lower than that in the EIS group (RR = 0.28, 95%CI: 0.13-0.58). CONCLUSION: Our meta-analysis has found that EVL is better than EIS in terms of the lower rates of rebleeding, complications, and the higher rate of variceal eradication. Therefore, EVL is the first choice for esophageal variceal bleeding.

Obesity is associated with increased colonic inflammation, which elevates the risk of colon cancer. Although exercise exerts anti-inflammatory actions in multiple chronic diseases associated with inflammation, it is unknown whether this strategy prevents colonic inflammation in obesity. We hypothesized that voluntary exercise would suppress colonic inflammation in high-fat diet (HFD)-induced obesity by modulation of peroxisome proliferator-activated receptor (PPAR)-γ. Male C57Bl/6J mice fed either a control diet (6.5% fat, CON) or a high-fat diet (24% fat, HFD) were divided into sedentary, voluntary exercise or voluntary exercise with PPAR-γ antagonist GW9662 (10 mg/kg/day). All interventions took place for 12 weeks. Compared with CON-sedentary group, HFD-sedentary mice gained significantly more body weight and exhibited metabolic disorders. Molecular studies revealed that HFD-sedentary mice had increased expression of inflammatory mediators and activation of nuclear factor (NF)-κB in the colons, which were associated with decreased expression and activity of PPAR-γ. Voluntary exercise markedly attenuated body weight gain, improved metabolic disorders, and normalized the expression of inflammatory mediators and activation of NF-κB in the colons in HFD-mice while having no effects in CON-animals. Moreover, voluntary exercise significantly increased expression and activity of PPAR-γ in the colons in both HFD- and CON-animals. However, all of these beneficial effects induced by voluntary exercise were abolished by GW9662, which inhibited expression and activity of PPAR-γ. The results suggest that decreased PPAR-γ activity in the colon of HFD-induced obesity may facilitate the inflammatory response and colon carcinogenesis. Voluntary exercise prevents colonic inflammation in HFD-induced obesity by up-regulating PPAR-γ activity.

This study was purposed to evaluate the efficacy and safety of nilotinib for treating patients with imatinib-resistant or intolerant chronic myeloid leukemia (CML). A total of 23 patients with imatinib-resistant or intolerant CML were enrolled in this study. These patients received nilotinib orally 600-800 mg every day, their curative efficacy, tolerance and overal survival were evaluated. The results showed that all the patients treated with nilotinib obtained complete hematologic remission (CHR), out of them 82.6% patients achieved complete cytogenetic remission (CCyR) and 56.5% patients achieved complete molecular remission (CMR), their adverse events mostly were mild to moderate, generally were transient and easily cured; the median treatment time with nilotinib was 13.5 (1-44) months, and the median follow-up time was 40 (12-102) months. It is concluded that nilotinib has been confirmed to be effective for patients with imatinib-resistant or intolerant CML, and may be selected as a second generation of tyrosine kinase inhibitor (TKI).

To evaluate whether the developmental potential of embryos that were partially damaged after freezing and thawing can be improved by removal of necrotic blastomeres. Eight-cell mouse embryos were cryopreserved using 1,2-propanediol and sucrose as cryoprotectant with slow cooling procedure. After thawing, blastocyst formation and hatching of fully intact embryos were compared between no treatment and with laser-assisted hatching. For partially intact embryos, the effects of removal of necrotic blastomeres with micromanipulation were evaluated. Laser-assisted hatching of mouse cryopreserved fully intact embryos significantly increased blastocyst hatching (63.4% versus 48.3%, P0.05), but had little effect on blastocyst formation (72.0% versus 70.1%, P0.05). The removal of necrotic blastomeres from partially damaged mouse cryopreserved embryos with micromanipulation significantly increased blastocyst formation (52.9% versus 32.0%, P0.05) and blastocyst hatching (41.2% versus 22.0%, P0.05) compared with the control group. The developmental potential of partially damaged cryopreserved embryos can be improved by removal of necrotic blastomeres with micromanipulation.

To investigate angiopoietin (Ang) and vascular endothelial growth factor (VEGF) expression in rats with ulcerative colitis (UC) and colorectal cancer (CRC).Dysplasia and cancer were investigated in rats that received three cycles of 3.5% dextran sulfate sodium (DSS) in drinking water for 7 d followed by distilled water for 14 d after intraperitoneal pretreatment with 20 mg/kg 1,2-dimethylhydrazine (DMH) (CRC group). Colitis was investigated in rats that received three cycles of 3.5% DSS in drinking water for 7 d followed by distilled water for 14 d after intraperitoneal pretreatment with saline (UC group). Rats without DSS or DMH treatment served as controls. Expression of the tyrosine kinase with immunoglobulin-like and EGF-like domains (Tie)-2 and its ligands, Ang-1 and Ang-2, as well as VEGF were evaluated in the colorectum by Western blotting.Compared with rats in the control group, rats in the CRC and UC groups developed the symptoms of acute colitis with diarrhea, rectal bleeding, wasting, and loss of body weight (P0.05). In addition, the mean length of colorectum of CRC and UC rats was significantly shorter than that of control rats (8.29 ± 0.21 and 8.31 ± 0.86, respectively, vs 12.34 ± 0.12 cm; P0.05). Furthermore, rats in the CRC group, but not in the UC or control groups, developed multiple tumors in the colorectal region. Western blot analysis revealed that rats in the CRC and UC groups had markedly increased protein levels of Ang-1, Ang-2, Tie-2, and VEGF in the colorectum compared to rats in the control group.Increased expression of Ang-1, Ang-2, Tie-2, and VEGF in ulcerative colitis-derived colorectal cancer might lead to chronic colitis and pathologic angiogenesis in rats.

When infrared focal plane array imaging system detects targets, especially small targets, there is the problem of low gray resolution. In this paper, an adaptive scene-based gray super-resolution technique is proposed, aiming to solve the problem. The paper gives a detailed description on the method of image gray super-resolution by adjusting the signal sample range in infrared focal plane array (IRFPA) imaging system. The method contains the following three parts: extracting the effective gray range from the scene, and obtaining the basis of super-resolution adjustment; providing the adjusting parameters after filter-predicting the basis of adjustment, combining with the adaptive LMS-based filtering algorithm; and completing gray super-resolution by controlling the parameters in super-resolution circuit. Finally, the total solution is experiment validated. The experiment in infrared focal plane array imaging system has proven the feasibility and effectiveness of this method, and the improvement of super-resolution. Then test set shows the MRTD can be increased more than one time.

Information on diets fed to captive giant pandas in five Chinese facilities (Beijing Zoo, Chengdu Zoo, China Conservation and Research Center, Fuzhou Zoo, and the Xian Zoo for the Giant Panda) in which pandas have successfully reproduced was compiled from publications and/or personal communications. Each facility feeds a steamed grain mixture comprising 13–56% of the diet on an as-fed basis, animal products (milk, eggs, and/or meat; 8–25% of the diet), and bamboo (17–82% of the diet). Seasonally available fruits and/or vegetables are sometimes included (0–29% of the diet). Typically, bamboo is offered throughout the day in small increments, while the remaining diet (concentrate portion) is fed in two meals. Despite the variety of ingredients in the concentrate recipes among institutions, there was remarkable similarity in nutrient composition: 55–65% water, 13–19% crude protein (CP), 2.5–4.0% crude fat (CF), and 2–5% ash (Ca, 0.2–0.9%; P, 0.4–0.8%) (all nutrients except water expressed on a dry matter (DM) basis). Calculated digestible energy content averaged about 3.3 kcal/kg DM. With the addition of animal products, bamboo, and produce, total diet composition averaged 51% water and, on a DM basis, 12% CP, 5.0% CF, 20–57% NDF (fiber), 0.5% Ca, 0.4% P, and 50–150 mg/kg vitamin E. These specifications are similar to nutrient requirements established for domestic canids and would appear adequate to meet the (as yet unestablished) requirements of the giant panda in captivity. Formulations for mineral and vitamin supplements to balance concentrate portions of these basic diets are included. © 1995 Wiley-Liss, Inc.

This study evaluated the effects of different cryoprotectants and cryopreservation protocols on the development of in vivo fertilized 2-4 cell mouse embryos. Mouse embryos were cryopreserved by using propylene glycerol (PG), ethylene glycerol (EG), dimethyl sulfoxide (DMSO) or glycerol (G) as cryoprotectant with slow-freezing or Vit-Master vitrification protocol. After thawing, the survival rate, blastocyst formation rate and blastocyst hatching rate of the embryos were compared. When mouse embryos were cryopreserved by the slow-freezing, survival rate, blastocyst formation rate and blastocyst hatching rate of the embryos with PG were significantly higher than those of DMSO and G (P0.05, respectively), but there is no significantly difference among those of DMSO, G and EG(p0.05), and between PG and EG. When mouse embryos were cryopreserved by Vit-Master vitrification, survival rate, blastocyst formation rate and blastocyst hatching rate of the embryos with EG were significantly higher than those of PG, DMSO and G (P0.05). There were no significant differences among those of PG, DMSO and G (p0.05). In conclusion, PG was the optimal cryoprotectant for the cryopreservation of 2-4 cell mouse embryos by slow-freezing protocol. EG was the optimal cryoprotectant for the cryopresevation of 2-4 cell mouse embryos by Vit-Master vitrification protocol, which may be commonly used in clinical and laboratory practice.

To understand the related knowledge, discrimination attitudes toward HIV/AIDS among medical college students, and to provide scientific evidence for further HIV/AIDS anti-discrimination intervention.By means of stratified cluster sampling to classes, 2844 undergraduate students were randomly selected from medical colleges. A self-designed and self-administered questionnaire survey was conducted, and SPSS 13.0 software was used for data analysis.2501 valid questionnaires had been collected. The overall HIV/AIDS knowledge coverage rate of the respondents was 73.1% (1828/2501); The HIV/AIDS discrimination rates in different questions were varying, the discrimination rate of infected with AIDS by bad sex and sharing needles was 83.1% (2078/2501) and 77.7% (1943/2501) respectively, the discrimination rates in term of contacting with HIV patients and their daily necessities, sharing desks, personal social were all exceeding 40%.The medical students held serious discrimination attitudes to HIV infected persons and patients; it is necessary to strengthen anti-discrimination education about HIV/AIDS among medical students.