[Effects of minimal residual disease level on day 33 of remission induction and IKZF1 genotype on the survival of children with B-lineage acute lymphoblastic leukemia].

OBJECTIVE: To study the effects of minimal residual disease (MRD) level on day 33 of remission induction and IKZF1 genotype on the survival of children with B-lineage acute lymphoblastic leukemia (B-ALL). METHODS: A total of 152 children with newly-diagnosed B-ALL who had complete remission after the first cycle of the chemotherapy and had complete follow-up information were enrolled in this study. According to the MRD detection by flow cytometry on day 33 of remission induction, they were divided into three groups: standard-risk (SR) group (MRD <10-4; n=60), intermediate-risk (IR) group (10-4≤ MRD <10-2; n=55), and high-risk (HR) group (MRD ≥10-2; n=37). Nested RT-PCR was used to determine the IKZF1 genotype of all children before chemotherapy. The effects of MRD level on day 33 of remission induction and IKZF1 genotype on the recurrence-free survival (RFS) of children with B-ALL were analyzed. RESULTS: There were 7 common IKZF1 subtypes in all the 152 children with B-ALL: IK1, IK2/3, IK4, IK6, IK8, IK9, and IK10. Of the 152 children, 130 had functional subtypes of IKZF1 and 22 had non-functional subtypes of IKZF1. During the follow-up period, relapse occurred in 26 (17%) children, and the recurrence rate was highest in the HR group (P<0.05). However, there was no significant difference in the recurrence rate between the SR group and the IR group (P>0.05). The cumulative recurrence rate of the children with non-functional subtypes of IKZF1 was significantly higher than that of those with functional types of IKZF1 (P<0.01). The predicted 5-year RFS rates in the SR, IR, and HR groups were (94.2±2.9)%, (86.7±3.8)%, and (56.2±4.5)% respectively (P<0.05). The 5-year RFS rate of the children with functional subtypes of IKZF1 was significantly higher than that of those with non-functional subtypes of IKZF1 (P<0.01). There was no significant difference in the predicted 5-year RFS rate between the children with functional subtypes of IKZF1 and those with non-functional subtypes of IKZF1 in the SR group (P>0.05). However, the predicted 5-year RFS rate of the children with functional subtypes of IKZF1 was significantly higher than that of those with non-functional subtypes of IKZF1 in the IR group and the HR group (P<0.05). CONCLUSIONS: B-ALL children with non-functional subtypes of IKZF1 have a high recurrence rate, and the recurrence rate will be even higher in B-ALL children with non-functional subtypes of IKZF1 and MRD ≥10-4 on day 33 of chemotherapy.

[Influence of thymidylate synthase gene polymorphisms on high-dose methotrexate-related toxicities in childhood acute lymphoblastic leukemia].

OBJECTIVE: To investigate the influence of thymidylate synthase (TS) gene polymorphisms on high-dose methotrexate (HD-MTX)-related toxicities in childhood acute lymphoblastic leukemia (ALL). METHODS: A total of 73 children who were diagnosed with ALL between March 2011 and March 2013 were included into this study. Genomic DNAs were extracted from their peripheral blood. And then the genotypes of TS 5'-UTR were determined by direct DNA sequencing after PCR. The toxicity response of 73 patients receiving HD-MTX chemotherapy were observed and recorded, and plasma MTX concentrations at 42-48 hours after chemotherapy were measured. RESULTS: The main HD-MTX-related toxicities of 73 patients receiving HD-MTX chemotherapy were neutropenia, decreased hemoglobin level, thrombocytopenia, liver toxicity, mucosal damage, and gastrointestinal reactions. There were no significant differences in the incidence rate of HD-MTX-related toxicities between children with different TS 5'-UTR genotypes after chemotherapy (P>0.05). TS 5'-UTR genotype was not significantly correlated with plasma MTX concentrations at 42-48 hours after chemotherapy (P>0.05). CONCLUSIONS: TS gene polymorphisms have no influence on the incidence of HD-MTX-related toxicities in childhood ALL.

Seasonal dynamics of the microbiota and nutritional composition in bee bread from Apis cerana and Apis mellifera colonies.

Bee bread is a product of honeybees, which collect and ferment pollen, that contains highly nutritious and easily digestible active substances. However, its nutritional composition varies significantly with fermentation strains and seasonal changes. To unveil the patterns of microbial community and nutritional component changes in bee bread across seasons, we employed high-throughput techniques to assess the diversity of bacteria and fungi in bee bread. The results indicated that the compositions of bacteria and fungi in bee bread undergo significant seasonal variation, with noticeable changes in the microbial diversity of bee bread from different bee species. Subsequently, metabolomic analysis revealed high activity of glycerophospholipid metabolism in bee bread. Furthermore, our analysis identifaied noteworthy differences in nutritional components, including pH values, sugar content, and free amino acid levels, in bee bread across different seasons.

[Effect of glucocorticoid on dendritic cells in children with chronic immune thrombocytopenia].

OBJECTIVE: To investigate the change in dendritic cells (DCs) in children with chronic immune thrombocytopenia (cITP) and the effect of glucocorticoid on DCs in children with cITP. METHODS: Fifteen children with cITP and 20 healthy controls were included in the study. Flow cytometry was used to measure the DC subsets count in the 15 children with cITP before and after glucocorticoid treatment as well as the corresponding values in the 20 healthy controls. The DCs derived from peripheral blood monocytes in children with cITP were cultured in vitro and collected, and their immunophenotypes were determined by flow cytometry. RESULTS: Before glucocorticoid treatment, the children with cITP showed no notable change in the absolute count of myeloid DCs (mDCs) but showed decreased absolute count of plasmacytoid DCs (pDCs) and increased mDC/pDC ratio compared with the healthy controls (P<0.05). After glucocorticoid treatment, the children with cITP demonstrated increased absolute count of pDCs and decreased absolute count of mDCs and mDC/pDC ratio compared with before treatment (P<0.05). Before glucocorticoid treatment, the children with cITP had significantly higher positive rates of HLA-DR, CD80, CD83 and CD86 on peripheral blood DCs than the healthy controls (P<0.01). All the positive rates were significantly decreased after glucocorticoid treatment (P<0.01), so that there was no significant difference from the healthy controls (P>0.05). CONCLUSIONS: Disproportion and functional disturbance of DC subsets is associated with the pathogenesis of cITP in children. Glucocorticoid can strengthen the immunosuppression of DCs in children with cITP, which may contribute to the effectiveness of glucocorticoid as a treatment.

Inoculation of Escherichia coli enriched the key functional bacteria that intensified cadmium accumulation by halophyte Suaeda salsa in saline soils.

The enhancement of cadmium (Cd) extraction by plants from contaminated soils associated with phosphate-solubilizing bacteria (PSB) has been widely reported, but the underlying mechanism remains scarcely, especially in Cd-contaminated saline soils. In this study, a green fluorescent protein-labeled PSB, the strain E. coli-10527, was observed to be abundantly colonized in the rhizosphere soils and roots of halophyte Suaeda salsa after inoculation in saline soil pot tests. Cd extraction by plants was significantly promoted. The enhanced Cd phytoextraction by E. coli-10527 was not solely dependent on bacterial efficient colonization, but more significantly, relied on the remodeling of rhizosphere microbiota, as confirmed by soil sterilization test. Taxonomic distribution and co-occurrence network analyses suggested that E. coli-10527 strengthened the interactive effects of keystone taxa in the rhizosphere soils, and enriched the key functional bacteria that involved in plant growth promotion and soil Cd mobilization. Seven enriched rhizospheric taxa (Phyllobacterium, Bacillus, Streptomyces mirabilis, Pseudomonas mirabilis, Rhodospirillale, Clostridium, and Agrobacterium) were obtained from 213 isolated strains, and were verified to produce phytohormone and promote soil Cd mobilization. E. coli-10527 and those enriched taxa could assemble as a simplified synthetic community to strengthen Cd phytoextraction through their synergistic interactions. Therefore, the specific microbiota in rhizosphere soils enriched by the inoculated PSB were also the key to intensifying Cd phytoextraction.

Gut microbiota-driven regulation of queen bee ovarian metabolism.

With the global prevalence of Varroa mites, more and more beekeepers resort to confining the queen bee in a queen cage to control mite infestation or to breed superior and robust queen bees. However, the impact of such practices on the queen bee remains largely unknown. Therefore, we subjected the queen bees to a 21-day egg-laying restriction treatment (from the egg stage to the emergence of adult worker bees) and analyzed the queen bees' ovarian metabolites and gut microbiota after 21 days, aiming to assess the queen bees' quality and assist beekeepers in better hive management. Our findings revealed a significant reduction in the relative expression levels of Vg and Hex110 genes in the ovaries of egg laying-restricted queen bees compared to unrestricted egg-laying queens. The diversity of gut microbiota in the queen bee exhibited a notable decrease, accompanied by corresponding changes in the core bacteria of the microbial community, the relative abundance of Lactobacillus and Bifidobacterium increased from 22.34% to 53.14% (P = 0.01) and from 0.053% to 0.580% (P = 0.04), respectively. The relative abundance of Bombella decreased from 25.85% to 1.720% (P = 0.002). Following egg-laying restriction, the activity of the queen bee's ovaries decreased, while the metabolism of glycerophospholipids remained or stored more lipid molecules, awaiting environmental changes for the queen bee to resume egg laying promptly. Furthermore, we observed that Bombella in the queen bee's gut may regulate the queen's ovarian metabolism through tryptophan metabolism. These findings provide novel insights into the interplay among queen egg laying, gut microbiota, and ovarian metabolism. IMPORTANCE With Varroa mite infestation, beekeepers often confine the queen bee in cages for control or breeding. However, the impact on the queen bee is largely unknown. We evaluated queen bee quality by restricting egg laying and analyzing ovarian metabolites and gut microbiota. In this study, we provided a comprehensive explanation of the expression of ovarian genes, the diversity of gut microbiota, and changes in ovarian metabolism in the queen bee. Through integrated analysis of the queen bee's gut microbiota and ovarian metabolism, we discovered that the gut microbiota can regulate the queen bee's ovarian metabolism. These findings provide valuable insights into the interplay among egg laying, gut microbiota, and the reproductive health of the queen bee. Understanding these relationships can contribute to the development of better strategies for Varroa mite control and queen bee breeding.

Long-term outcome of children with acute promyelocytic leukemia: a randomized study of oral versus intravenous arsenic by SCCLG-APL group.

Realgar-Indigo naturalis formula (RIF), an oral traditional Chinese medicine mainly containing Realgar (As4S4), is highly effective in treating adult acute promyelocytic leukemia (APL). However, the treatment efficacy and safety of RIF have not been verified in pediatric patients. SCCLG-APL group conducted a multicenter randomized non-inferiority trial to determine whether intravenous arsenic trioxide (ATO) can be substituted by oral RIF in treating pediatric APL. Of 176 eligible patients enrolled, 91 and 85 were randomized to ATO and RIF groups, respectively. Patients were treated with the risk-adapted protocol. Induction, consolidation, and 96-week maintenance treatment contained all-trans-retinoic acid and low-intensity chemotherapy, and either ATO or RIF. The primary endpoint was 5-year event-free survival (EFS). The secondary endpoints were adverse events and hospital days. After a median 6-year follow-up, the 5-year EFS was 97.6% in both groups. However, the RIF group had significantly shorter hospital stays and lower incidence of infection and tended to have less cardiac toxicity. All 4 relapses occurred within 1.5 years after completion of maintenance therapy. No long-term arsenic retentions were observed in either group. Substituting oral RIF for ATO maintains treatment efficacy while reducing hospitalization and adverse events in treating pediatric APL patients, which may be a future treatment strategy for APL.

Honeybee (Apis mellifera) resistance to deltamethrin exposure by Modulating the gut microbiota and improving immunity.

Honeybees (Apis mellifera) are important economic insects and play important roles in pollination and maintenance of ecological balance. However, the use of pesticides has posed a substantial threat to bees in recent years, with the more widely used deltamethrin being the most harmful. In this study, we found that deltamethrin exposure significantly reduced bee survival in a dose-dependent manner (p = 0.025). In addition, metagenomic sequencing further revealed that DM exposure significantly reduced the diversity of the bee gut microbiota (Chao1, p < 0.0001; Shannon, p < 0.0001; Simpson, p < 0.0001) and decreased the relative abundance of core species of the gut microbiota. Importantly, in studies of GF-bees, we found that the colonization of important gut bacteria such as Gilliamella apicola and Lactobacillus kunkeei significantly increased bee resistance to DM (survival rate increased from 16.7 to 66.7%). Interestingly, we found that the immunity-genes Defensin-2 and Toll were significantly upregulated in bees after the colonization of gut bacteria. These results suggest that gut bacteria may protect against DM stress by improving host immunity. Our findings provide an important rationale for protecting honeybees from pollutants from the perspective of gut microbes.

Effects of spinetoram and glyphosate on physiological biomarkers and gut microbes in Bombus terrestris.

The sublethal effects of pesticide poisoning will have significant negative impacts on the foraging and learning of bees and bumblebees, so it has received widespread attention. However, little is known about the physiological effects of sublethal spinetoram and glyphosate exposure on bumblebees. We continuously exposed Bombus terrestris to sublethal (2.5 mg/L) spinetoram or glyphosate under controlled conditions for 10 days. The superoxide dismutase, glutathione-S-transferase, carboxylesterase, prophenoloxidase, α-amylase and protease activities, and changes in gut microbes were measured to understand the effects of sublethal pesticide exposure on the physiology and gut microbes of bumblebees. Sublethal pesticide exposure to significantly increased superoxide dismutase activity and significantly decreased gut α-amylase activity in bumblebees but had no significant effect on glutathione-S-transferase, carboxylesterase or gut protease activities. In addition, glyphosate increased the activity of prophenoloxidase. Interestingly, we observed that neither of the two pesticides had a significant effect on dominant gut bacteria, but glyphosate significantly altered the structure of the dominant gut fungal community, and reduced the relative abundance of Zygosaccharomyces associated with fat accumulation. These results suggest that sublethal spinetoram and glyphosate do not significantly affect the detoxification system of bumblebees, but may affect bumblebee health by inhibiting energy acquisition. Our results provide information on the sublethal effects of exposure to low concentrations of glyphosate and spinetoram on bumblebees in terms of physiology and gut microbes.

Nitrogen fertilizer management affects remobilization of the immobilized cadmium in soil and its accumulation in crop tissues.

Immobilization of soil cadmium (Cd) has been the strategy mostly used in remediation of Cd-contaminated arable soil. However, Cd might be remobilized after the immobilization process through the acid-soluble and complexation effects. Development of agronomic management technologies to prevent soil Cd remobilization after the immobilization process was an important pathway to control the food safety of agricultural products in soils with the immobilized Cd. In this study, the ammonia (NH4+-N) and nitrate (NO3--N) forms with concentrations of 60, 90, and 150 mg-N kg-1 soil were performed for evaluating their effects on Cd remobilization with planted or unplanted treatments and Cd accumulation in tissues of edible amaranth (Liuye). With an initial soil palygorskite-bound fraction Cd concentration of 0.6 mg kg-1, bioavailable Cd in rhizosphere soils and Cd in crop shoots respectively increased from 11.4 to 20.6 µg kg-1 (dry soil weight) and 6.92 to 14.92 mg kg-1 (dry plant weight) in planted NH4+-N treatments, while significantly lower concentrations of bioavailable Cd in rhizosphere soils and Cd in crop tissues were observed with planted NO3--N treatments. Compared with that of planted NO3--N treatments, decreasing pH value (i.e., 7.64 to 7.18) induced by root proton efflux during the absorption of NH4+-N, enhancive organic/amino acid (oxalic acid, lactic acid, L-proline, and so on) secretion from roots, and increasing abundance of bacteria distributed in phyla Proteobacteria, Cyanobacteria, and Bacteroidetes with Cd mobilization ability in rhizosphere soils were the main reasons found in this study for the higher Cd remobilization in soils and Cd accumulation in crop under NH4+-N treatments. Moreover, the direct effect of NH4+-N on remobilization of immobilized Cd by upregulating the expression abundances of genes associated with pyruvate metabolism and amino acids metabolism was more significant than that of NO3--N. In summary, the use of NO3--N as preferred N fertilizer was more efficient to ensure the food safety of agricultural products than that of NH4+-N in Cd-contaminated arable soil after immobilization process.

Nitrogen fertilizer affects rhizosphere Cd re-mobilization by mediating gene AmALM2 and AmALMT7 expression in edible amaranth roots.

In-situ stabilization of Cd-contaminated farmland is a commonly used remediation technology. Yet, rhizosphere metabolites (e.g., organic acids) during crop cultivation may cause Cd re-mobilization and over-accumulation. Here, we identified four pivotal cytomembrane-localized genes underlying Cd accumulation difference between two contrasting edible amaranth cultivars based on root gene expression profile, studied their subcellular localization and functional characteristics, and then investigated effects of nitrogen fertilizer on their expression and rhizosphere Cd re-mobilization. Results showed that more Cd accumulated by edible amaranth was due to rhizosphere Cd mobilization by mediating high expression of AmALMT2 and AmALMT7 genes, not Cd transporters in roots. This was confirmed by heterologous expression of AmALMT2 and AmALMT7 genes in Arabidopsis thaliana, since they mediated malic, fumaric, succinic, and aspartic acids efflux. Furthermore, nitrogen influencing rhizosphere acidification might be closely associated with organic acids efflux genes. Compared with N-NO3- application, N-NH4+ was massively assimilated into glutamates and oxaloacetates through up-regulating glutamine synthetase and alanine-aspartate-glutamate metabolic pathways, thereby enhancing TCA cycle and organic acids efflux dominated by binary carboxylic acids via up-regulating AmALMT2 and AmALMT7 genes, which finally caused Cd re-mobilization. Therefore, N-NO3--dominated nitrogen retarded rhizosphere Cd re-mobilization via inhibiting organic acids efflux function of AmALMT2 and AmALMT7 proteins.

Biomineralization of Cd2+ and inhibition on rhizobacterial Cd mobilization function by Bacillus Cereus to improve safety of maize grains.

Reducing cadmium (Cd) bioavailability and rhizobacterial Cd mobilization functions in the rhizosphere via the inoculation of screened microbial inoculum is an environmental-friendly strategy to improve safety of crop grains. In this study, Bacillus Cereus, a model Cd resistant strain, was selected to explore its effects on Cd bioavailability and uptake, bacterial metabolic functions related to Cd mobilization. Results indicated that inoculation of Bacillus Cereus in maize roots of sand pot with water-soluble Cd (0.06-0.15 mg/kg) and soil pot with high Cd-contaminated soil (total Cd: 2.33 mg/kg; Cd extracted by NH4NO3: 38.6 µg/kg) could decrease water-soluble Cd ion concentration by 7.7-30.1% and Cd extracted with NH4NO3 solution by 7.8-22.5%, inducing Cd concentrations in maize grains reduced by 10.6-39.9% and 17.4-38.6%, respectively. Even for a single inoculation in soil, Cd concentration in maize grains still satisfy food safety requirements (Cd content: 0.1 mg/kg dry weight) due to its successful colonization on root surface of maize. Bacillus Cereus could enrich more plant growth promotion bacteria (PGPB) and down-regulate the expression of genes related to bacterial motility, membrane transports, carbon and nitrogen metabolism in the rhizosphere soil, decreasing Cd bioavailability in soil. Approximately 80% Cd2+ in media was transferred into intracellular, meanwhile Cd salts (sulfide and/or phosphate) were produced in Bacillus Cereus through biomineralization process. Overall, this study could provide a feasible method for improving safety of maize grains via the inoculation of Bacillus Cereus under Cd pollution.

Improving cadmium mobilization by phosphate-solubilizing bacteria via regulating organic acids metabolism with potassium.

Organic acids secreted by phosphorus-solubilizing bacteria (PSB) is one of the main biological metabolites with cadmium (Cd) mobilization capacity in the conversion of insoluble precipitate forms to bioavailable forms in contaminated soil. However, the fluctuating concentrations of nutrient elements caused by agricultural activities may result in the substantial variances of carbohydrate metabolism of microorganisms involved in Cd remediation, it is therefore essential to study how metabolic strategies, especially for organic acids, affected by the environmentally friendly fertilizers, such as potassium (K). In this study, adding K+ (KCl) concentrations from 0.0 to 100.0 mg/L in medium clearly accelerated Cd mobilization from 15.9 to 35.9 mg/L via inducing the secretion of tartaric acid, 3-hydroxybutyrate, fumaric and succinic acids, increased by 10.0-, 7.5-, 4.3- and 4.1-fold changes, respectively. Current data revealed that the significant differences of metabolic pathways and genes expressions with the varied K+ concentrations included: ⅰ) K+ induces a substantial up-regulation in metabolic pathway of pyruvic acid to oxaloacetate and tartaric acids; ⅱ) the varied expression of genes involved in encoding enzymes of tricarboxylic acid cycle result in the up-regulated fumaric acid, succinic acid and 3-hydroxybutyrate; ⅲ) the expression of genes related enzyme cysteine and glutamate metabolism processes promoted with the increasing bioavailable Cd concentrations. Besides, P-type ATPase activity increased with K+ levels, indicating that H+ efflux and medium acidification were strengthened. In general, an appropriate enhancement of K based fertilizer is an effective manner for soil Cd remediation via the regulation of organic acids metabolism and H+ secretion of PSB.

[Clinical Significance of CRLF2 High Expression in Bone Marrow Mononuclear Cells from Children with Acute Lymphoblastic Leukemia].

OBJECTIVE: To detect the expression of CRLF2 in bone marrow mononuclear cells from children with newly diagnosed acute lymphoblastic leukemia(ALL) and to explore its clinical significance in pediatric ALL. METHODS: A total of 218 children with newly diagnosed ALL who achieveal the complete remission and had the complete follow-up information were selected, and the expression level of CRLF2 in bone marrow mononuclear cells of these children was detected by real-time fluorescent quantitative PCR, and the significance of CRLF2 expression level in clinical prognosis of ALL children was analyzed by using statistical method. RESULTS: 28 cases in 218 children with complete data showed high expression of CRLF2. The cumulative recurrence rate in the CRLF2 high expression group was significantly higher than that in the low expression group (53.6% vs 12.6%) (P＜0.01). The predicted 5-year recurrence-free survival rate (RFS) of ALL children with CRLF2 high expression was significantly higher than that of low expression group (P＜0.01). There was no significant difference in the predicted 5-year RFS between ALL children with CRLF2 low and high expression in the standard-risk(SR) group (P＞0.05). The predicted 5-year RFS of ALL children with CRLF2 low expression was higher than that of ALL children with CRLF2 high expression in the intermediate-risk (IR) and high-risk (HR) groups. (P＜0.05). Cox analysis showed that CRLF2 high expression is an independent risk factor for the relapse of children with ALL. CONCLUSION: The recurrence rate of pediatric ALL with CRLF2 high expression is high, and CRLF2 high expression is an important prognostic factor for high risk of relapse in ALL children with IR and HR. It is necessary to use CRLF2 expression as an indicator of risk stratification in pediatric ALL.

[Investigation on effect of PVP on morphological changes and crystallization behavior of nylon 6 in PVP/nylon 6 blends by FTIR spectroscopy].

Temperature-dependent FT IR, DSC and POM were used to investigate the interaction between PVPK90 and nylon 6 molecules and its effect on the thermal behavior and morphology of nylon 6. DSC results suggest that the melting and crystallization behavior of nylon 6 are obviously influenced by the introduction of PVP. With the PVP content increasing, the crystallization temperature, melting temperature and the crystallinity of nylon 6 decreased, and eventually, both the exothermal and endothermic peaks could not be observed when the PVP content reached 80%, implying that the aggregation structure of nylon 6 changes from the crystalline state to the amorphous state. FTIR provided the evidence of the interaction between PVP and nylon 6 molecules. With the increase in PVP content, the peak position of nu N-H of nylon 6 gradually shifts from 3311 to 3300 cm(-1) with 90% content of PVP, and the half height peak width is broadened correspondingly. Three peaks were obtained in the carbonyl group absorption band for PVPK90/Nylon 6(50/50) and PVPK90/Nylon 6(80/20) blends from the curve-fitting results. With the addition of PVP molecules, the nu C=O of nylon 6 shifts to higher wave number and a new peak located at about 1620 cm(-1) appears and its peak area increases with the content of PVP. The above spectral variation of nu C=O and nu N-H in the PVPK90/Nylon 6 blend indicates that the carbonyl group of PVP could form H-bonding with N-H group of nylon 6 molecule, and partially destroy the hydrogen bonding between the nylon 6 molecules. POM results showed that the spherulitic size of nylon 6 decreases with the increment of the PVP and becomes more imperfect, and when the PVP content reaches 80%, no spherulites could be observed. This phenomenon is attributed to the molecular interactions between the PVP and the nylon 6 molecules, which weakens the free mobility of nylon 6 chains to form regular packing and eventually induces the change in the spherulitic morphology of nylon 6. In summary, the molecular interactions between the carbonyl group of PVP molecules and N-H group of nylon 6 molecules account for the above changes in the crystalline structure and the morphology of nylon 6 in the blends.

[Investigation of follicular development and oocyte maturation after cryopreservation and xenograft of newborn mouse ovaries].

In order to explore the feasibility of cryopreserving primordial follicles in attaining their developmental competence following freezing and thawing, ovaries from newborn mice were cryopreserved and the thawed ovaries were xenografted into kidney capsules of adult female mice. Ovaries were isolated from newborn B6C2F(1) female mice, infiltrated by Leibovitz 15 (L-15) medium containing 10% (V/V) fetal bovine serum (FBS) and 1.5 mol/L dimethylsulfoxide (DMSO), and then packed into 0.25 ml plastic straws. The ovaries contained in straws were frozen under nitrogen vapour at -40 degrees C in Cryocell 1200 programmable freezer, and stored in liquid nitrogen for periods ranging from 1 week to 6 months. Upon thawing, the straws were dipped into room temperature water for 10~20 s, after which the ovaries were collected and washed in L-15 buffer containing 10% (V/V) FBS without DMSO to remove cryoprotectant. The thawed ovaries were transplanted into kidney capsules of 8~12-week old adult B6C2F(1) female recipient mice by two protocols, with either 1 or 2 ovaries in each capsule. Upon withdrawal after at least 14 d of transplantation, only 45.00% (72/160) of the ovaries were recovered from 40 recipients transplanted with 2 ovaries in each capsule, compared to 82.50% (33/40) in 20 recipients with only 1 ovary in each capsule. The grafted ovaries exhibited similar follicular developmental progression to that of natural ovaries. There were antral follicles present in the transplanted ovaries on day 14, whose number increased more substantially on day 19 after transplantation. Following stimulation of the recipient mice with 10 IU PMSG on day 19 after xenografting, follicles further developed to preovulatory stage with appearance of cumulus oocytes and enlarged antrum. Oocytes from these fully grown antral follicles were collected and matured in vitro in modified essential medium-alpha (MEMalpha). After 16~17 h of culture, 40.90% of the oocytes exhibited germinal vesicle breakdown (GVBD) and among which 89.02% proceeded to the metaphase II (MII) stage as indicated by exclusion of the first polar body. The remaining oocytes were further cultured and 50.83% of which initiated GVBD by 20~21 h of culture, but only 21.40% of which proceeded to MII. The above results demonstrated that the primordial follicles in newborn mouse ovaries were capable of sustaining freezing and thawing, and reinitiating development following xenograft into kidney capsule in adult recipient female mice. Production of mature oocytes from such re-developed follicles following gonadotrophin priming and the subsequent oocyte in vitro maturation implied immense prospect of application of this method to preserve female germ cells, conserve endangered species, establish animal gene stock, and utilize oocytes in assisted reproductive techniques.

[Establishment of the guinea pig model of synovial tuberculosis of knee joint by mycobacterium tuberculosis H37Rv infection].

OBJECTIVE: To explore how to establish the guinea pig model of synovial tuberculosis of knee joint by mycobacterium tuberculosis H37Rv infection. METHODS: Two doses (1 x 10(7)/mL, 50 microL and 100 microL) of Mycobacterium strains were injected into the knee joint of the guinea pig that had been immunized and allergized with Freund's complete adjuvant six weeks previously. The pathological changes of the synovial membrane, cartilage and bone after infection of mycobacterium tuberculosis were investigated. At the same time, the synovial membrane tissues and culture for the mycobacterium tuberculosis were collected and examined. RESULTS: After the infection of mycobacterium tuberculosis H37Rv, the knee joint of guinea pig became swollen, but the interference to the whole conditions of the guinea pig was slight in both infection groups. The tissue sections of the synovial membrane showed tubercle and caseous necrosis of the knee joint in both groups. The mycobacterium tuberculosis could be detected by using Ziehl-neelsen stain and the culture from the synovial membrane of the knee joint. CONCLUSION: By injecting suitable dosage of mycobacterium H37Rv strains into the joint of the immunized and allergized guinea pig, we have established the guinea pig model of synovial tuberculosis that is pathologically similar to synovial tuberculosis in humans, so it is fit for use in the diagnostic studies and pathological researches.

Missed diagnosis of oesophageal perforation in ankylosing spondylitis cervical fracture: Two case reports and literature review.

Oesophageal perforation after blunt injury cervical fracture in patients with ankylosing spondylitis (AS) is rarely reported. The early diagnosis of oesophageal perforation is extremely important. We present two cases of patients with AS who sustained cervical fracture dislocation and spinal cord injury. The ossified sharp fragments caused oesophageal perforation, and the delayed diagnoses had serious consequences. Oesophageal perforation should be suspected in patients with AS and cervical fracture if bone fragments are pressing against the oesophagus and a gas shadow is visible around the fracture site on computed tomography imaging.

Activation of novel estrogen receptor GPER results in inhibition of cardiocyte apoptosis and cardioprotection.

Several studies have recently demonstrated that G protein-coupled estrogen receptor (GPER) 30 directly binds to estrogen and mediates its action. The aim of the present study was to investigate the effects of GPER on cardiocyte apoptosis following ischemia/reperfusion injury (MIRI) in H9C2 myocardial cells. H9C2 cells were treated with a specific GPER agonist (G1), 17ß-estradiol (E2) or the vehicle. The cells were subjected to 20 min of myocardial ischemia followed by 120 min of reperfusion. They were then randomly assigned to three experimental groups: Control, G1, E2. B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated X (Bax) levels were measured, Hoechst 33258 staining was performed to assess apoptosis, and superoxide dismutase (SOD), tumor necrosis factor (TNF)-α and adenosine triphosphatase (ATPase) levels were determined. To test the specificity of G1, GPER-knockout cells were treated with G1 and analyzed as stated above. Compared with the vehicle-treated groups, G1 and E2-treated groups exhibited elevated Bcl-2 levels, decreased Bax levels and cell apoptosis, significantly increased SOD and ATP levels and decreased TNF-α levels following ischemia-reperfusion. However, G1 had no evident effects on the GPER-knockout cells. In conclusion, the present study suggested that GPER activation provided a cardioprotective effect following ischemia-reperfusion by inhibiting cardiocyte apoptosis.

[Study on decellularized laryngeal scaffold in dogs].

OBJECTIVE: To explore the survivorship and character of decellularized laryngeal scaffold in pectoralis major muscle flap in canine. METHODS: Eighteen donor larynx in experimental group were decellularized by perfusing sodium dodecyl sulphate. Three of them were used to detect the character of histology. The other fifteen ones were embedded in right pectoralis major muscle flap of acceptor canine. Donor larynx in control group were not perfused. Other experimental procedure was the same as experimental group. The specimens were harvested at two weeks, one month and two months after operation, respectively. Macroscopic view, histological examination and trypan blue staining were performed in the experimental group and control group. RESULTS: The size of the specimens decreased remarkably into disappearance in control group, there was statistical significance between the experimental group and the control group (which used least significant difference t test P < 0.05). There was only little neutrophils and lymphocytes infiltrating around the laryngeal scaffold at 2 weeks in the experimental group. One month after operation, loose connective tissue begin to form around the laryngeal scaffold. After two months of transplantation, the connective tissue became thicker and the number of blood vessels increased than before. There was a large number of lymphocytes and neutrophil infiltration around the laryngeal specimens in the control group at 2nd week. The perichondrium in the control group was damaged at one month post operation. The cartilage cells could not be detected two months after surgery. The survival rate of cartilage cell between experimental group (86.8% ± 3.2%) and the control group (88.6% ± 3.1%) did not show statistical significance before implantation (χ(2) = 0.19, P > 0.05). The survival rate of cartilage cell decreased insignificantly in experimental group while the survival rate declined obviously in the control group at two weeks and one month after operation, the difference had statistical significance (χ(2) were respectively 5.52 and 20.55, P were respectively < 0.05 and < 0.01), the survival rate of cartilage cell in experimental group was (65.8% ± 2.6%) at two months after operation, while the cartilage cell all disappeared in control group. CONCLUSIONS: Perfused decellularation technique can construct a low immunogenicity laryngeal cartilage scaffold which can survive in the chest muscle package and establish a good blood supplement. The decellularized laryngeal scaffold could be used as a biological scaffold for whole laryngeal reconstruction.