BACKGROUNDParagonimiasis is a typical food-borne zoonotic disease. Hosts acquire Paragonimusinfection through the ingestion of raw or undercooked crayfish and crab.The clinical manifestations of the disease are varied...BACKGROUNDParagonimiasis is a typical food-borne zoonotic disease. Hosts acquire Paragonimusinfection through the ingestion of raw or undercooked crayfish and crab.The clinical manifestations of the disease are varied, and it is often misdiagnosedor missed. The diagnosis of paragonimiasis should be considered comprehensively.Praziquantel is the first choice for treatment, and albendazole can beused in combination with repeated courses in severe cases.CASE SUMMARYWe report a case of liver paragonimiasis that was misdiagnosed as an abscess. Thepatient presented with fatigue and poor appetite for 2 months, and was diagnosedwith liver abscess in the local hospital. After 6 months, the patient visited ourhospital because of recurrent abdominal pain and was diagnosed with liverparagonimiasis based on epidemiological history, clinical presentations, andlaboratory findings. He was treated with praziquantel (25 mg/kg) three times aday for 3 days;however, the symptoms still presented after treatment. He wastreated with oral praziquantel and albendazole for one further course. Follow-upsuggested that the treatment was effective and the symptoms improved.CONCLUSIONThe combination of albendazole and praziquantel may improve the therapeuticefficacy of paragonimiasis.展开更多
The effect of genotypic diversity on the age structure and bud bank of the Leymus chinensis population has not yet been demonstrated.This experiment was designed to study the age structure of the tiller,rhizome,and bu...The effect of genotypic diversity on the age structure and bud bank of the Leymus chinensis population has not yet been demonstrated.This experiment was designed to study the age structure of the tiller,rhizome,and bud of L.chinensis at genotypic diversity levels of 1,2,4,8,and 12.A total of 64 communities were established in this experiment,following the principle of randomized block experimental design.The results indicated that genotypic diversity had a significant or obviously significant effect on the cumulative length of rhizomes of 2a and 4a,dry matter accumulation of rhizomes of 1a and 2a,tiller number of 1a,tiller productivity of 3a,but had no significant effect age structure of buds.As the levels of genotypic diversity increased,the proportion of the cumulative length of rhizomes with 4a decreased and then increased,and dry matter accumulation of rhizomes with 1a and 2a gradually increased while the number of tillers with 1a gradually decreased,when the gradient of genotypic diversity increased.At the 1,2,4,8,and 12 genotype diversity levels,the number of tillers,the cumulative length of rhizomes,and dry matter accumulation in rhizomes and buds were all age structures of expanding type.However,tiller productivity was an expanding or stable age structure at levels of 1,2,4,8 genotypic diversity,while it was a declining age structure at the 12 genotype diversity gradient.An appropriate genotypic diversity is conducive to maintaining the growth and stability of the age structure of L.chinensis population,but too high a gradient of genotypic diversity can have a negative impact on the population age structure.This study provided that an appropriate number of genotypic diversity contributes to the stability of the population.展开更多
Objective: To compare the efficacy and adverse effects of paclitaxel-etoposide-carboplatin/cisplatin(TEP/TCE) regimen with those of etoposide-carboplatin/cisplatin(EP/CE) regimen as first-line treatment for combined s...Objective: To compare the efficacy and adverse effects of paclitaxel-etoposide-carboplatin/cisplatin(TEP/TCE) regimen with those of etoposide-carboplatin/cisplatin(EP/CE) regimen as first-line treatment for combined small-cell lung cancer(CSCLC).Methods: A retrospective study was conducted on 62 CSCLC patients who were treated at Tianjin Medical University Cancer Institute and Hospital from July 2000 to April 2013 and administered with TEP/TCE regimen(n=19) or EP/CE regimen(n=43) as first-line CSCLC treatment. All patients received more than two cycles of chemotherapy, and the response was evaluated every two cycles. The primary endpoint was overall survival(OS), and the secondary endpoints were progression-free survival(PFS), objective response rate(ORR), disease control rate(DCR), and adverse effects. Results: ORR between the TEP/TCE and EP/CE groups showed a statistical difference(90% vs. 53%, P=0.033). Both groups failed to reach a statistical difference in DCR(100% vs. 86%, P=0.212). The median PFS and OS of the TEP/TCE group were slightly longer than those of the EP/CE group, although both groups failed to reach a statistical difference(10.5 vs. 8.9 months, P=0.484; 24.0 vs. 17.5 months, P=0.457). However, stratified analysis indicated that the PFS of patients with stages III and IV CSCLC showed marginally significant difference between the TEP/TCE and EP/CE groups(19.5 vs. 7.6 months; P=0.071). Both rates of grade IV bone marrow depression and termination of chemotherapy in the TEP/TCE group were significantly higher than those in the EP/CE group(26.3% vs. 7.0%, P=0.036; 31.6% vs. 14.7%, P=0.004). Conclusion: The TEP/TCE regimen may not be preferred for CSCLC, and this three-drug regimen requires further exploration and research. To date, the EP/CE regimen remains the standard treatment for CSCLC patients.展开更多
This paper mainly introduced the preparation of silk fibroin membranes and their structural change characteristics.Silk fibroin membranes can be used as tissue engineering materials,enzyme-immobilizing membranes,biose...This paper mainly introduced the preparation of silk fibroin membranes and their structural change characteristics.Silk fibroin membranes can be used as tissue engineering materials,enzyme-immobilizing membranes,biosensors and drug controlled-release membranes and other different materials.They have excellent characteristics such as non-toxic,non-polluting and degradable,and thus have broad application prospects.展开更多
Ramet modules in a certain population differ in terms of functions,which accounts for different contributions of the same ramets.Shortening heading time brings about different contributions of such modules.Ramets head...Ramet modules in a certain population differ in terms of functions,which accounts for different contributions of the same ramets.Shortening heading time brings about different contributions of such modules.Ramets heading one after another were treated as a continuum in respective cohorts of Elymus cylindricus aged two.The reproductive ramets that head earlier were marked with tags every four days during the whole heading stage from the beginning to the end,after which all the labeled ramets at the maturity period were gathered.The results showed that,the height and biomass of ramets,the length and biomass of inflorescences,percentage of inflorescence length to ramet height,percentage of inflorescence biomass to ramet biomass,the number and biomass of seeds,seed-setting rate,and percentage of seed biomass to ramet biomass declined with the increasing intensity of heading time shortening as displayed with linear or quadratic function.Ramet characteristics weakened remarkably when shortened heading time added up to 17 days.The biomass distribution in relation to inflorescence and seed maintain a stable rate at the early heading stage and dwindled quickly at the near-end stage,but the biomass of ramets remain constant throughout the entire heading stage.The ramets with earlier heading time make greater contribution to the survival of population than the shortened heading time in this species of bunchgrass.展开更多
The planting and afforestation of mulberry and its application as animal feed conform to the spirit that comprehensive utilization of biomass such as agriculture and forestry is the direction of sustainable developmen...The planting and afforestation of mulberry and its application as animal feed conform to the spirit that comprehensive utilization of biomass such as agriculture and forestry is the direction of sustainable development in the National Program for Medium-to-Long-Term Scientific and Technological Development . The application of mulberry as animal feed has attracted international attention, but the cultivar identification of forage mulberry is still controversial in the industry. The paper summarizes the current situation of forage mulberry in animal husbandry, and expounds how to define and classify forage mulberry.展开更多
Silk can promote the penetration of oxygen and water and support the attachment and proliferation of neurons and Schwann cells,and has appropriate biodegradation kinetics and flexible physical strength.It is a high-qu...Silk can promote the penetration of oxygen and water and support the attachment and proliferation of neurons and Schwann cells,and has appropriate biodegradation kinetics and flexible physical strength.It is a high-quality natural tissue engineering material and can be used as an ideal matrix for nerve repair.This paper reviewed the structure and properties of silk and the research progress of silk nerve conduits in peripheral nerve regeneration in recent years,and prospected its clinical application.展开更多
Silk sericin is a natural polymer,which is often discarded as waste in silk reeling production.Sericin protein increases the COD value of degumming wastewater and increases the difficulty of sewage treatment.The recov...Silk sericin is a natural polymer,which is often discarded as waste in silk reeling production.Sericin protein increases the COD value of degumming wastewater and increases the difficulty of sewage treatment.The recovery and utilization of sericin protein can minimize environmental problems,and has high scientific and commercial value.This paper introduced and analyzed current technical methods of recycling sericin from silk degumming wastewater,providing a reference for the utilization of recovered sericin.展开更多
Embryo implantation in both humans and rodents is initiated by the attachment of a blastocyst to the uterine epithelium.For blastocyst attachment,the uterine epithelium needs to transform at both the structural and mo...Embryo implantation in both humans and rodents is initiated by the attachment of a blastocyst to the uterine epithelium.For blastocyst attachment,the uterine epithelium needs to transform at both the structural and molecular levels first,and then initiate the interaction with trophectoderm.Any perturbation during this process will result in implantation failure or long-term adverse pregnancy outcomes.Endocrine steroid hormones,which function through nuclear receptors,combine with the local molecules produced by the uteri or embryo to facilitate implantation.The insulin-like growth factor(IGF)signaling has been reported to play a vital role during pregnancy.However,its physiological function during implantation remains elusive.This study revealed that mice with conditional deletion of Igflr gene in uteri suffered from subfertility,mainly due to the disturbed uterine receptivity and abnormal embryo implantation.Mechanistically,we uncovered that in response to the nidatory estrogen on D4 of pregnancy,the epithelial IGF1R,stimulated by the stromal cell-produced IGF1,facilitated epithelial STAT3 activation to modulate the epithelial depolarity.Furthermore,embryonic derived IGF2 could activate both the epithelial ERK1/2 and STAT3 signaling through IGF1R,which was critical for the transcription of Cox2 and normal attachment reaction.In brief,our data revealed that epithelial IGF1R was sequentially activated by the uterine stromal IGF1 and embryonic IGF2 to guarantee normal epithelium differentiation during the implantation process.展开更多
Assays based on high-performance liquid chromatography(HPLC)and liquid chromatography tandem mass spectrometry(LC–MSn)have been developed and validated for the determination and metabolite identification of the bides...Assays based on high-performance liquid chromatography(HPLC)and liquid chromatography tandem mass spectrometry(LC–MSn)have been developed and validated for the determination and metabolite identification of the bidesmosidic triterpenoid saponin,BTS-1(3-O-β-D-galactopyranosyl-(1-2)-[β-D-xylopyranosyl-(1-3)]-β-D-glucuronopyranosyl gypsogenin 28-O-α-L-arabinopyranosyl-(1-3)-βD-xylopyranosyl-(1-4)-α-L-rhamnopyranosyl-(1-2)-β-D-fucopyranoside),in rat plasma.The assay was successfully applied to a pharmacokinetic study in rats given a single oral dose of BTS-1(400 mg/kg).The results indicated that the compound was rapidly absorbed(Tmax=1.2870.29 h,Cmax=37.475.6 mg/mL)and slowly eliminated(t1/2=13.276.6 h).In addition,secondary glycosides and aglycones of BTS-1 were detected and identified.Since these metabolites are known to be activeα-glucosidase inhibitors,they probably play an important role in mediating the pharmacological effects of the saponin.展开更多
In this paper, sequence unique reconstruction refers to the property that a sequence is uniquely reconstructable from all its K-tuples. We propose and study the phase transition behavior of the probability P(K) of u...In this paper, sequence unique reconstruction refers to the property that a sequence is uniquely reconstructable from all its K-tuples. We propose and study the phase transition behavior of the probability P(K) of unique reconstruction with regard to tuple size K in random sequences (iid model). Based on Monte Carlo experiments, artificial proteins generated from lid model exhibit a phase transition when P(K) abruptly jumps from a low value phase (e.g. 〈 0.1) to a high value phase (e.g. 〉 0.9). With a generalization to any alphabet, we prove that for a random sequence of length L, as L is large enough, P(K) undergoes a sharp phase transition when p ≤ 0.1015 where p = P (two random letters match). Besides, formulas are derived to estimate the transition points, which may be of practical use in sequencing DNA by hybridization. Concluded from our study, most proteins do not deviate greatly from random sequences in the sense of sequence unique reconstruction, while there are some "stubborn" proteins which only become uniquely reconstructable at a very large K and probably have biological implications.展开更多
Proper development of the human placenta is of vital importance for a successful pregnancy,and a series of pregnancy complications are considered originating from dysfunctional placentas.Like other organ system develo...Proper development of the human placenta is of vital importance for a successful pregnancy,and a series of pregnancy complications are considered originating from dysfunctional placentas.Like other organ system development,placentation requires large numbers of co-regulators,while the underlying molecular mechanisms orchestrating the placental formation and function are poorly understood.Although we have made many signs of progress in understanding the placental architectures and developments using mouse models,the species-specific differences impede our progress due to the lack of appropriate model systems.In the past few years,major progress has been made by the establishment of novel in-vitro self-renewing stem cell models,as well as identifying the full picture of the cellular organization of the maternal and fetal interface.Providing the tools for the investigation of placentation and reproductive-related regulation mechanism.In this review,we focus on the detailed progress of the human trophoblast stem cells culturing system,and the cellular and molecular terrain at the maternal-fetal interface,respectively,thus providing new insights into placental development.展开更多
文摘BACKGROUNDParagonimiasis is a typical food-borne zoonotic disease. Hosts acquire Paragonimusinfection through the ingestion of raw or undercooked crayfish and crab.The clinical manifestations of the disease are varied, and it is often misdiagnosedor missed. The diagnosis of paragonimiasis should be considered comprehensively.Praziquantel is the first choice for treatment, and albendazole can beused in combination with repeated courses in severe cases.CASE SUMMARYWe report a case of liver paragonimiasis that was misdiagnosed as an abscess. Thepatient presented with fatigue and poor appetite for 2 months, and was diagnosedwith liver abscess in the local hospital. After 6 months, the patient visited ourhospital because of recurrent abdominal pain and was diagnosed with liverparagonimiasis based on epidemiological history, clinical presentations, andlaboratory findings. He was treated with praziquantel (25 mg/kg) three times aday for 3 days;however, the symptoms still presented after treatment. He wastreated with oral praziquantel and albendazole for one further course. Follow-upsuggested that the treatment was effective and the symptoms improved.CONCLUSIONThe combination of albendazole and praziquantel may improve the therapeuticefficacy of paragonimiasis.
基金supported by the National Natural Science Foundation of China(32071860).
文摘The effect of genotypic diversity on the age structure and bud bank of the Leymus chinensis population has not yet been demonstrated.This experiment was designed to study the age structure of the tiller,rhizome,and bud of L.chinensis at genotypic diversity levels of 1,2,4,8,and 12.A total of 64 communities were established in this experiment,following the principle of randomized block experimental design.The results indicated that genotypic diversity had a significant or obviously significant effect on the cumulative length of rhizomes of 2a and 4a,dry matter accumulation of rhizomes of 1a and 2a,tiller number of 1a,tiller productivity of 3a,but had no significant effect age structure of buds.As the levels of genotypic diversity increased,the proportion of the cumulative length of rhizomes with 4a decreased and then increased,and dry matter accumulation of rhizomes with 1a and 2a gradually increased while the number of tillers with 1a gradually decreased,when the gradient of genotypic diversity increased.At the 1,2,4,8,and 12 genotype diversity levels,the number of tillers,the cumulative length of rhizomes,and dry matter accumulation in rhizomes and buds were all age structures of expanding type.However,tiller productivity was an expanding or stable age structure at levels of 1,2,4,8 genotypic diversity,while it was a declining age structure at the 12 genotype diversity gradient.An appropriate genotypic diversity is conducive to maintaining the growth and stability of the age structure of L.chinensis population,but too high a gradient of genotypic diversity can have a negative impact on the population age structure.This study provided that an appropriate number of genotypic diversity contributes to the stability of the population.
基金supported by grants from the Tianjin Municipal Science and Technology Project (Grant No. 11JCYBJC11300)National Natural Science Foundation of China (Grant No. 81372517)National Science and Technology Major Project (Grant No. 09303001)
文摘Objective: To compare the efficacy and adverse effects of paclitaxel-etoposide-carboplatin/cisplatin(TEP/TCE) regimen with those of etoposide-carboplatin/cisplatin(EP/CE) regimen as first-line treatment for combined small-cell lung cancer(CSCLC).Methods: A retrospective study was conducted on 62 CSCLC patients who were treated at Tianjin Medical University Cancer Institute and Hospital from July 2000 to April 2013 and administered with TEP/TCE regimen(n=19) or EP/CE regimen(n=43) as first-line CSCLC treatment. All patients received more than two cycles of chemotherapy, and the response was evaluated every two cycles. The primary endpoint was overall survival(OS), and the secondary endpoints were progression-free survival(PFS), objective response rate(ORR), disease control rate(DCR), and adverse effects. Results: ORR between the TEP/TCE and EP/CE groups showed a statistical difference(90% vs. 53%, P=0.033). Both groups failed to reach a statistical difference in DCR(100% vs. 86%, P=0.212). The median PFS and OS of the TEP/TCE group were slightly longer than those of the EP/CE group, although both groups failed to reach a statistical difference(10.5 vs. 8.9 months, P=0.484; 24.0 vs. 17.5 months, P=0.457). However, stratified analysis indicated that the PFS of patients with stages III and IV CSCLC showed marginally significant difference between the TEP/TCE and EP/CE groups(19.5 vs. 7.6 months; P=0.071). Both rates of grade IV bone marrow depression and termination of chemotherapy in the TEP/TCE group were significantly higher than those in the EP/CE group(26.3% vs. 7.0%, P=0.036; 31.6% vs. 14.7%, P=0.004). Conclusion: The TEP/TCE regimen may not be preferred for CSCLC, and this three-drug regimen requires further exploration and research. To date, the EP/CE regimen remains the standard treatment for CSCLC patients.
基金Supported by Chongqing Natural Science Foundation Project(18219)Chongqing Scientific Research Institution Performance Incentive Project(19537,20521)+1 种基金Chongqing Rongchang Agriculture and Animal Husbandry High Tech Industry R&D Special Project(20209)Chongqing Modern Mountain Characteristic Benefit Agriculture(Sericulture)Technology System Diversified Development Research Office(18304).
文摘This paper mainly introduced the preparation of silk fibroin membranes and their structural change characteristics.Silk fibroin membranes can be used as tissue engineering materials,enzyme-immobilizing membranes,biosensors and drug controlled-release membranes and other different materials.They have excellent characteristics such as non-toxic,non-polluting and degradable,and thus have broad application prospects.
基金This work was funded under the auspices of the Natural Key Research and Development Program of China(2016YFC0500602)National Natural Science Foundation of China(31672471,31472134,www.nsfc.gov.cn,YFY+1 种基金31570332,www.nsfc.gov.cn,CZ)the Program of Introducing Talents of Discipline to Universities(B16011).
文摘Ramet modules in a certain population differ in terms of functions,which accounts for different contributions of the same ramets.Shortening heading time brings about different contributions of such modules.Ramets heading one after another were treated as a continuum in respective cohorts of Elymus cylindricus aged two.The reproductive ramets that head earlier were marked with tags every four days during the whole heading stage from the beginning to the end,after which all the labeled ramets at the maturity period were gathered.The results showed that,the height and biomass of ramets,the length and biomass of inflorescences,percentage of inflorescence length to ramet height,percentage of inflorescence biomass to ramet biomass,the number and biomass of seeds,seed-setting rate,and percentage of seed biomass to ramet biomass declined with the increasing intensity of heading time shortening as displayed with linear or quadratic function.Ramet characteristics weakened remarkably when shortened heading time added up to 17 days.The biomass distribution in relation to inflorescence and seed maintain a stable rate at the early heading stage and dwindled quickly at the near-end stage,but the biomass of ramets remain constant throughout the entire heading stage.The ramets with earlier heading time make greater contribution to the survival of population than the shortened heading time in this species of bunchgrass.
基金Supported by Development of Low-Immunogenicity&Water-Soluble Silk Fibroin(22541C)Chongqing Scientific Research Institution Performance Incentive Project(22529J,22531J)+1 种基金Chongqing Rongchang Agriculture and Animal Husbandry High-tech Industry R&D Special Project(20209)Chongqing Modern Mountain Characteristic Benefit Agriculture(Sericulture)Technology System Diversified Development Research Office(18304).
文摘The planting and afforestation of mulberry and its application as animal feed conform to the spirit that comprehensive utilization of biomass such as agriculture and forestry is the direction of sustainable development in the National Program for Medium-to-Long-Term Scientific and Technological Development . The application of mulberry as animal feed has attracted international attention, but the cultivar identification of forage mulberry is still controversial in the industry. The paper summarizes the current situation of forage mulberry in animal husbandry, and expounds how to define and classify forage mulberry.
基金Supported by Development of Low-immunogenicity&Water-soluble Silk Fibroin(22541C)Chongqing Scientific Research Institution Performance Incentive Project(22529J and 22531J)Chongqing Rongchang Agriculture and Animal Husbandry High-tech Industry R&D Special Project(20209).
文摘Silk can promote the penetration of oxygen and water and support the attachment and proliferation of neurons and Schwann cells,and has appropriate biodegradation kinetics and flexible physical strength.It is a high-quality natural tissue engineering material and can be used as an ideal matrix for nerve repair.This paper reviewed the structure and properties of silk and the research progress of silk nerve conduits in peripheral nerve regeneration in recent years,and prospected its clinical application.
基金Supported by Chongqing Natural Science Foundation Project(18219)Chongqing Scientific Research Institution Performance Incentive Project(19537,20521)+1 种基金Chongqing Rongchang Agriculture and Animal Husbandry High-tech Industry R&D Special Project(20209)Chongqing Modern Mountain Characteristic Benefit Agriculture(Sericulture)Technology System Diversified Development Research Office(18304).
文摘Silk sericin is a natural polymer,which is often discarded as waste in silk reeling production.Sericin protein increases the COD value of degumming wastewater and increases the difficulty of sewage treatment.The recovery and utilization of sericin protein can minimize environmental problems,and has high scientific and commercial value.This paper introduced and analyzed current technical methods of recycling sericin from silk degumming wastewater,providing a reference for the utilization of recovered sericin.
基金supported by the National Key R&D Program of China(2017YFC1001402 to H.W.2018YFC1004401 to S.K.)+1 种基金the National Natural Science Foundation of China(81830045 and 82030040 to H.W.,81971388 to S.K.)Institution of Higher Education Projects of Building First-class Discipline Construction in Ningxia Region(NXYLXK2017B05 to G.X.).
文摘Embryo implantation in both humans and rodents is initiated by the attachment of a blastocyst to the uterine epithelium.For blastocyst attachment,the uterine epithelium needs to transform at both the structural and molecular levels first,and then initiate the interaction with trophectoderm.Any perturbation during this process will result in implantation failure or long-term adverse pregnancy outcomes.Endocrine steroid hormones,which function through nuclear receptors,combine with the local molecules produced by the uteri or embryo to facilitate implantation.The insulin-like growth factor(IGF)signaling has been reported to play a vital role during pregnancy.However,its physiological function during implantation remains elusive.This study revealed that mice with conditional deletion of Igflr gene in uteri suffered from subfertility,mainly due to the disturbed uterine receptivity and abnormal embryo implantation.Mechanistically,we uncovered that in response to the nidatory estrogen on D4 of pregnancy,the epithelial IGF1R,stimulated by the stromal cell-produced IGF1,facilitated epithelial STAT3 activation to modulate the epithelial depolarity.Furthermore,embryonic derived IGF2 could activate both the epithelial ERK1/2 and STAT3 signaling through IGF1R,which was critical for the transcription of Cox2 and normal attachment reaction.In brief,our data revealed that epithelial IGF1R was sequentially activated by the uterine stromal IGF1 and embryonic IGF2 to guarantee normal epithelium differentiation during the implantation process.
基金supported by the National Natural Science Foundation of China(No.81073009)a Project Fund from The Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Assays based on high-performance liquid chromatography(HPLC)and liquid chromatography tandem mass spectrometry(LC–MSn)have been developed and validated for the determination and metabolite identification of the bidesmosidic triterpenoid saponin,BTS-1(3-O-β-D-galactopyranosyl-(1-2)-[β-D-xylopyranosyl-(1-3)]-β-D-glucuronopyranosyl gypsogenin 28-O-α-L-arabinopyranosyl-(1-3)-βD-xylopyranosyl-(1-4)-α-L-rhamnopyranosyl-(1-2)-β-D-fucopyranoside),in rat plasma.The assay was successfully applied to a pharmacokinetic study in rats given a single oral dose of BTS-1(400 mg/kg).The results indicated that the compound was rapidly absorbed(Tmax=1.2870.29 h,Cmax=37.475.6 mg/mL)and slowly eliminated(t1/2=13.276.6 h).In addition,secondary glycosides and aglycones of BTS-1 were detected and identified.Since these metabolites are known to be activeα-glucosidase inhibitors,they probably play an important role in mediating the pharmacological effects of the saponin.
文摘In this paper, sequence unique reconstruction refers to the property that a sequence is uniquely reconstructable from all its K-tuples. We propose and study the phase transition behavior of the probability P(K) of unique reconstruction with regard to tuple size K in random sequences (iid model). Based on Monte Carlo experiments, artificial proteins generated from lid model exhibit a phase transition when P(K) abruptly jumps from a low value phase (e.g. 〈 0.1) to a high value phase (e.g. 〉 0.9). With a generalization to any alphabet, we prove that for a random sequence of length L, as L is large enough, P(K) undergoes a sharp phase transition when p ≤ 0.1015 where p = P (two random letters match). Besides, formulas are derived to estimate the transition points, which may be of practical use in sequencing DNA by hybridization. Concluded from our study, most proteins do not deviate greatly from random sequences in the sense of sequence unique reconstruction, while there are some "stubborn" proteins which only become uniquely reconstructable at a very large K and probably have biological implications.
基金This work was supported in parts by the National Key R&D Program of China(2017YFC1001402 to H.W.,2018YFC1004102 to J.L.)National Natural Science Foundation of China(81490744 to H.W.,31600945 to J.L.and 31701016 to J.W.)+2 种基金Fujian Natural Science Foundation(2017J01071 to J.L.)the Fundamental Research Funds for the Central Universities(20720180041 J.L.)Foundation from Key Laboratory of Reproduction Regulation of NPFPC(2017KF01 to J.L.).The funders had no role in study design,data collection,and analysis,decision to publish,or preparation of the manuscript
文摘Proper development of the human placenta is of vital importance for a successful pregnancy,and a series of pregnancy complications are considered originating from dysfunctional placentas.Like other organ system development,placentation requires large numbers of co-regulators,while the underlying molecular mechanisms orchestrating the placental formation and function are poorly understood.Although we have made many signs of progress in understanding the placental architectures and developments using mouse models,the species-specific differences impede our progress due to the lack of appropriate model systems.In the past few years,major progress has been made by the establishment of novel in-vitro self-renewing stem cell models,as well as identifying the full picture of the cellular organization of the maternal and fetal interface.Providing the tools for the investigation of placentation and reproductive-related regulation mechanism.In this review,we focus on the detailed progress of the human trophoblast stem cells culturing system,and the cellular and molecular terrain at the maternal-fetal interface,respectively,thus providing new insights into placental development.