Recognition and Anticipation of Diabetic Foot Ulcer in Type Ⅱ Diabetic Patients using Multi-layered Fuzzy Model

Diabetes mellitus is associated with foot ulcers,which frequently pave the way to lower-extremity amputation.Neuropathy,trauma,deformity,high plantar pressures,and peripheral vascular disease are the most common underlying causes.Around 15%of diabetic patients are affected by diabetic foot ulcer in their lifetime.64 million people are affected by diabetics in India and 40000 amputations are done every year.Foot ulcers are evaluated and classified in a systematic and thorough manner to assist in determining the best course of therapy.This paper proposes a novel model which predicts the threat of diabetic foot ulcer using independent agents for various input values and a combination of fuzzy expert systems.The proposed model uses a classification system to distinguish between each fuzzy framework and its parameters.Based on the severity levels necessary prevention,treatment,and medication are recommended.Combining the results of all the fuzzy frameworks derived from its constituent parameters,a risk-specific medication is recommended.The work also has higher accuracy when compared to other related models.

Analysis of a Type Ⅱ Snowstorm Process in the Early Spring of 2022 in Ulanqab

Based on the observation data of meteorological stations,Doppler radar observation data of Ulanqab City,and ERA-5 reanalysis data,a snowstorm process in Ulanqab City from March 17 to 18,2022 was analyzed.The results show that this was a type Ⅱ snowstorm process generated under the joint influence of upper trough and ground low inverted trough and frontal cyclone.The main period of snowfall can be divided into two time stages,and the total snowfall was more in the south and less in the north,which was consistent with that of average specific humidity field.Water vapor conditions provided by strong water vapor transport and convergence,strong upward movement shown by large vertical velocity field,and the suction action of high-and low-layer divergence and convergence were the reasons for the hourly heavy snowfall on the 18^(th).During the process,radar echoes were mainly sheet-shaped,and composite reflectivity was 15-25 dBZ in most areas.The zero speed line in the first period was positively"S"-shaped,and there was warm advection and southwest wind.On the morning of the 18^(th),after the cold front transited the city,Ulanqab City was gradually controlled by northwest wind,and the snow tended to end.

Effect of glycosides of Cistanche on the expression of mitochondrial precursor protein and keratin type Ⅱ cytoskeletal 6A in a rat model of vascular dementia

Glycosides of Cistanche（GC）is a preparation used extensively for its neuroprotective effect against neurological diseases,but its mechanisms of action remains incompletely understood.Here,we established a bilateral common carotid artery occlusion model of vascular dementia in rats and injected the model rats with a suspension of GC（10 mg/kg/day,intraperitoneally）for 14 consecutive days.Immunohistochemistry showed that GC significantly reduced p-tau and amyloid beta（Aβ）immunoreactivity in the hippocampus of the model rats.Proteomic analysis demonstrated upregulation of mitochondrial precursor protein and downregulation of keratin type II cytoskeletal6A after GC treatment compared with model rats that had received saline.Western blot assay confirmed these findings.Our results suggest that the neuroprotective effect of GC in vascular dementia occurs via the promotion of neuronal cytoskeleton regeneration.

The remedial effect of soluble interleukin-1 receptor type Ⅱ on endometriosis in the nude mouse model

Objective： Recent studies have shown that the local expression of soluble interleukin （IL） -1 receptor type Ⅱ （slL-1 R Ⅱ ） in endometrial tissue of women with endometriosis is decreased, and the depression of IL-1 R Ⅱ was more significant in infertile women than that in fertile women with endometriosis. In this research, we investigated the remedial effect of slL-1-R Ⅱ administration on endometriosis in the nude mouse model. Methods： Nineteen nude model mice with endometriosis were randomly divided into three groups： group A was treated by intraperitoneal administration with only slL-1 R Ⅱ for two weeks, group B was similarly treated with only IL- 1, and group C （control） was administered saline. After 2 weeks, the size of the ectopic endometrial lesions was calculated, and the expression of vascular endothelial growth factor （VEGF） and B-cell lymphoma leukemia-2 （Bcl- 2） were detected by immunohistochemistry. The IL-8 and VEGF levels in the peritoneal fluid （PF） and serum were also measured by enzyme-linked immunosorbent assay （ELISA）. Results： The mean size of ectopic endometrial lesion did not differ between the three groups （P 〉 0.05）. Compared with the control, the expression of VEGF and Bcl-2 was significantly lower in group A, and higher in group B. In the three groups, the levels of IL-8 in the PF and serum were highest in group A, and lowest in group B. Conclusion： slL-1 R Ⅱ may suppresse hyperplasia of ectopic endometriosis, perhaps by reducing the expression of certain cytokines, such as VEGF, IL-8, and Bcl-2, which could provide a new clinical strategy for the treatment of endometriosis.

Primary Culture of Alveolar Epithelial Type Ⅱ Cells and Its Bionomic Study

To establish a better method of primary culture for alveolar epithelial type Ⅱ cells （AEC Ⅱ ） and to study its bionomics, alveolar epithelial type Ⅱ cells were isolated by digestion with trypsin and collagenase, which were then purified by plated into culture flask coated with rat immunoglobulin （i The purified AEC Ⅱ were identified by alkaline phosphatase staining, electron mi- croscopy, immunocytochemical staining of pulmonary surfactant protein A （SPA）. The SPA expression and transfection characteristics were compared with those of A549 cell line. The results showed that AEC Ⅱ could be isolated by digestion with trysin and collagenase and purified by adhesive purification by using IgG, with a yield of about 2-3 × 10^7, and a purity of about 75%-84 %. Cells could be quickly identified with AKP staining. AEC Ⅱ were different from A549 cell line in terms of SPA expression and transfection characteristics. It is concluded that adhesive purification with IgG can improve the purity of AEC Ⅱ, and AKP staining is simple in cell identification. AEC Ⅱ can not be completely replaced by A549 cells in some studies because the differences between them, such as SPA expression.

环F_2+uF_2+…+u^kF_2上的Type Ⅱ码

给出一种构造环F2+uF2+…+ukF2上任意偶数长度的自正交和自对偶码的方法.定义了环F2+uF2+…+ukF2的每个元素的Euclidean重量并且证明了环F2+uF2+…+ukF2上的自对偶码是Euclidean重量为2k+2倍数的TypeⅡ码.

Influence of morphine on levels of type Ⅱ inhibitory guanine nucleotide binding protein in primary hippocampal neurons

BACKGROUND： The pharmacological action of opioid drugs is related to signal transduction of inhibitory guanine nucleotide binding protein. OBJECTIVE： To quantitatively and qualitatively analyze the influence of morphine on levels of type Ⅱ inhibitory guanine nucleotide binding protein （Gi2 protein） in primary cultured hippocampal neurons at different time points. DESIGN, TIME AND SETTING： A randomized controlled study, which was performed at the Department of Neurobiology, Changzheng Hospital, Second Military Medical University of Chinese PLA between September 2002 and March 2004. MATERIALS： Cerebral hippocampal neurons were obtained from newborn SD rats at 1 2 days of age. Biotin-antibody Ⅱ-avidin fluorescein isothiocyanate （Avidin-FITC） was purchased from Sigma Company （USA） and the Gi2 protein polyclonal antibody from Santa Cruz Biochemistry Company （USA）. METHODS： Seven days after culture, mature hippocampal neurons were randomly divided into six groups： 4-, 8-, 16-, 24-, and 48-hour morphine groups, and a blank control group. Neurons in the morphine groups received morphine （10 μ mol/L）, which could cause alterations of G-protein mRNA and cAMP expression in the prefrontal cortex. Neurons in the blank control group were given the same volume of saline. MAIN OUTCOME MEASURES： Gi2 protein levels were detected by an immunofluorescence technique, and were analyzed by the image analytic system with the use of green fluorescence intensity. RESULTS： Gi2 protein levels in hippocampal neurons gradually decreased in the 4-, 8-, 16-, 24-, and 48-hour morphine groups. In particular, Gi2 protein levels in the 16-, 24-, and 48-hour morphine groups were significantly lower than that in the blank control group （P 〈 0.05 0.01）. CONCLUSION： Morphine may decrease Gi2 protein level in primary hippocampal neurons, and the decreasing trend is positively related to morphine-induced time.

BAYESIAN PREDICTION FOR THE TWO-PARAMETER EXPONENTIAL DISTRIBUTION BASED ON TYPE Ⅱ DOUBLY CENSORING

The two-parameter exponential distribution is proposed to be an underlying model,and prediction bounds for future observations are obtained by using Bayesian approach.Prediction intervals are derived for unobserved lifetimes in one-sample prediction and two-sample prediction based on type Ⅱ doubly censored samples.A numerical example is given to illustrate the procedures,prediction intervals are investigated via Monte Carlo method,and the accuracy of prediction intervals is presented.

Teriparatide anabolic therapy as potential treatment of type Ⅱ dens non-union fractures

Odontoid fractures account for 5% to 15% of all cervical spine injuries and 1% to 2% of all spine fractures. Type Ⅱ fractures are the most common fracture pattern in elderly patients. Treatment(rigid and non-rigid immobilization, anterior screw fixation of the odontoid and posterior C1-C2 fusion) remains controversial and represents a unique challenge for the treating surgeon. The aims of treatment in the elderly is to quickly restore pre-injury function while decreasing morbidity and mortality associated with inactivity, immobilization with rigid collar and prolonged hospitalization. Conservative treatment of type Ⅱ odontoid fractures is associated with relatively high rates of non-union and in a few cases delayed instability. Options for treatment of symptomatic non-unions include surgical fixation or prolonged rigid immobilization. In this report we present the case of a 73-year-old woman with post-traumatic odontoid nonunion successfully treated with Teriparatide systemic anabolic therapy. Complete fusion and resolution of the symptoms was achieved 12 wk after the onset of the treatment. Several animal and clinical studies have confirmed the potential role of Teriparatide in enhancing fracture healing. Our case suggests that Teriparatide may have a role in improving fusion rates of C2 fractures in elderly patients.

Glutaric acidemia type Ⅱ patient with thalassemia minor and novel electron transfer flavoprotein-A gene mutations:A case report and review of literature

Glutaric acidemia type Ⅱ （GAⅡ）, also known as multiple acyl-CoA dehydrogenase defciency, is an auto-somal recessive inborn error of amino acid and fatty acid metabolism. We report a case of GAⅡ with novel electron transfer flavoprotein （ETF）-A mutations in a 2-year-old female with thalassemia minor. The patient developed an episode of hypoglycemia and hypotonicityon the postnatal first day. Laboratory investigations revealed elevations of multiple acyl carnitines indicat-ing glutaric acidemia type Ⅱ in newborn screening analysis. Urinary organic acids were evaluated for the confrmation and revealed a high glutaric acid excretion. Genetic analysis revealed two novel mutations in the ETF-A gene, which are considered to be compound heterozygote. At the 8 mo of life ketone therapy was added, which significantly increased the neuromotor development. The patient had been closely followed for two years with carnitine, ribofavin, coenzyme Q10, and ketone supplementation in addition to a high carbohydrate diet. Although the patient had comorbidity like thalassemia minor, her neuromotor developmentwas normal for her age and had no major health problems. This specific case expands the previously reported spectrum of this disease.

Type Ⅱ VLDLR promotes cell migration by up-regulation of VEGF, MMP2 and MMP7 in breast cancer cells

Objective： Very low density lipoprotein receptor （VLDLR） has been considered as a multiple function receptor due to binding numerous ligands, causing endocytosis and regulating cellular signaling. Our group previously reported that type II VLDLR overexpression in breast cancer tissues. The purpose of this study is to characterize type II VLDLR activities during cell migration using breast cancer cell lines. Methods： Western blotting was used to test protein expression. Cell migration was analyzed by Scratch wound assay. The mRNA expression was tested by realtime-PCR. Reporter assay was to test the transcription activity. Results： Scratch wound and Report assay indicated up-regulated VLDLR II expression promotes cell migration via activating Wnt/β-catenin pathway. The target genes such as VEGF, MMP2 and MMP7 were upregulated in VLDLR II overexpressed cells. On the contrary, cells treated with TFPI had an inhibition effect of cell migration response to down-regulation of VLDLR Ⅱ. Conclusion： Type Ⅱ VLDLR conferred a migration and invasion advantage by activating Wnt/β- catenin pathway, then up-regulating VEGF, MMP2 and MMP7 in breast cancer cells.

Mimicking natural cholesterol assimilation to elevate the oral delivery of liraglutide for type Ⅱ diabetes therapy

Glucagon-like peptide-1 receptor agonists(GLP-1 RA)are a series of polypeptides broadly applied in the long-term treatment of typeⅡdiabetes.However,administration of GLP-RA is mainly through repetitive subcutaneous injection,which may seriously decrease the compliance and safety.Herein,a bio-inspired oral delivery system was designed to enhance the oral absorption of liraglutide(Lira),a kind of GLP-1 RA,by mimicking the natural cholesterol assimilation.25-hydroxycholesterol(25HC),a cholesterol derivative,was modified on the surfaced of Lira-loaded PLGA nanoparticles(Lira 25HC NPs)and functioned as a“top-down”actuator to facilitate unidirectional transcytosis across the intestinal epithelium.After oral delivery,Lira 25HC NPs displayed improved therapeutic effect as compared with oral free Lira on typeⅡdiabetes db/db mice,as evidenced by multiple relieved diabetic symptoms including the enhanced glucose tolerance,repressed weight growth,improved liver glucose metabolism,decreased fasting blood glucose,HbA 1c,serum lipid,and increasedβcells activity.Surprisingly,the fasting blood glucose,liver glucose metabolism,and HbA1c of oral Lira-loaded 25HC NPs were comparable to subcutaneous injection of free Lira.Further mechanisms revealed that 25HC ligand could mediate the nanoparticles to mimic natural cholesterol absorption by exerting high affinity towards apical Niemann-Pick C1 Like 1(NPC1L1)and then basolateral ATP binding cassette transporter A1(ABCA1)overexpressed on the opposite side of intestinal epithelium.This cholesterol assimilation-mimicking strategy achieve the unidirectional transport across the intestinal epithelium,thus improving the oral absorption of liraglutide.In general,this study established a cholesterol simulated platform and provide promising insight for the oral delivery of GLP-1 RA.

Adjuvant chemoradiotherapy vs adjuvant chemotherapy in locally advanced Siewert type Ⅱ/Ⅲ adenocarcinoma of gastroesophageal junction after D2/R0 resection

BACKGROUND For Siewert type Ⅱ/Ⅲ adenocarcinoma of gastroesophageal junction(AGE), the efficacy of adjuvant chemoradiotherapy(CRT) after D2/R0 resection remains uncertain.AIM To determine whether CRT was superior to chemotherapy(CT) alone after D2/R0 resection for locally advanced Siewert type Ⅱ/Ⅲ AGE.METHODS We identified 316 locally advanced Siewert type Ⅱ/Ⅲ AGE patients who were treated with D2/R0 resection at National Cancer Center from 2011 to 2018.57 patients received adjuvant CRT and 259 patients received adjuvant CT.We followed patients for overall survival(OS), relapse-free survival, and recurrence pattern.RESULTS Five-year OS rates of the CRT group and the CT group for all patients were 66.7% and 41.9%(P = 0.010).Five-year OS rates of the CRT group and the CT group for Siewert type Ⅲ AGE patients were 65.7% and 43.9%(P = 0.006).Among the 195 patients whose recurrence information could be obtained, 18 cases(34.6%) and 61 cases(42.7%) were diagnosed as recurrence in the CRT group and CT group, respectively.The local and regional recurrence rates in the CRT group were lower than that in the CT group(22.2% vs 24.6%, 27.8% vs 39.3%).Multivariable cox regression analysis showed that vascular invasion, nerve invasion, and adjuvant CRT were important prognostic factors for Siewert type Ⅲ AGE.CONCLUSION For locally advanced Siewert type Ⅲ AGE, adjuvant CRT may prolong OS and reduce the regional recurrence rate.

Integrated Design of D.D.I., Filament Winding and Curing Processes for Manufacturing the High Pressure Vessel(Type Ⅱ)

As energy crisis and environment pollution all around the world threaten the widespread use of fossil fuels,compressed natural gas(CNG)vehicles are explored as an alternative to the conventional gasoline powered vehicles.Because of the limited space available for the car,the composite pressure vessel(TypeⅡ)has been applied to the CNG vehicles to reach large capacity and weight lightening vehicles.High pressure vessel(TypeⅡ)is composed of a composite layer and a metal liner.The metal liner is formed by the deep drawing and ironing(D.D.I.)process,which is a complex process of deep drawing and ironing.The cylinder part is reinforced by composite layer wrapped through the filament winding process and is bonded to the liner by the curing process.In this study,an integrated design method was presented by establishing the techniques for FE analysis of entire processes(D.D.I.,filament winding and curing processes)to manufacture the CNG composite pressure vessel(TypeⅡ).Dimensions of the dies and the punches of the 1 st(cup drawing),2 nd(redrawing-ironing 1-ironing 2)and 3 rd(redrawing-ironing)stages were calculated theoretically,and shape of tractrix die to be satisfied with the minimum forming load was suggested for life improvement and manufacturing costs in the D.D.I.process.Thickness of the composite material was determined in the filament winding process,finally,conditions of the curing process(number of heating stage,curing temperature,heating rate and time)were proposed to reinforce adhesive strength between the composite layers.

具Holling-type Ⅱ型功能反应的随机时滞捕食系统的研究

研究了具Holling-typeⅡ型功能反应的随机时滞捕食系统.通过构造合适的Lyapunov函数,利用伊藤公式讨论了该类随机系统的动力学行为.首先,证明了对任何给定的正初始条件,该随机系统都存在唯一的全局正解.其次,分析了解的随机最终有界性,保证了随机系统的有效性.最后,给出了解的渐近矩估计.得出结论:即使很小的随机扰动也能够保证种群的有界性.解的这些性质为生物资源管理提供了一定的理论依据.

Poorly controlled type Ⅱ diabetes mellitus significantly enhances postoperative chemoresistance in patients with stage Ⅲ colon cancer

BACKGROUND Type Ⅱ diabetes mellitus(T2DM)has been associated with increased risk of colon cancer(CC)and worse prognosis in patients with metastases.The effects of T2DM on postoperative chemoresistance rate(CRR)and long-term disease-free survival(DFS)and overall survival(OS)in patients with stage Ⅲ CC who receive curative resection remain controversial.AIM To investigate whether T2DM or glycemic control is associated with worse postoperative survival outcomes in stage Ⅲ CC.METHODS This retrospective cohort study included 278 patients aged 40-75 years who underwent surgery for stage Ⅲ CC from 2018 to 2021.Based on preoperative T2DM history,the patients were categorized into non-DM(n=160)and DM groups(n=118).The latter was further divided into well-controlled(n=73)and poorly controlled(n=45)groups depending on the status of glycemic control.DFS,OS,and CRR were compared between the groups and Cox regression analysis was used to identify risk factors.RESULTS Patients in the DM and non-DM groups demonstrated similar DFS,OS,and CRR(DFS:72.03%vs 78.75%,P=0.178;OS:81.36%vs 83.12%,P=0.638;CRR:14.41%vs 7.5%,P=0.063).Poorly controlled DM was associated with a significantly worse prognosis and higher CRR than well-controlled DM(DFS:62.22%vs 78.07%,P=0.021;OS:71.11%vs 87.67%,P=0.011;CRR:24.40%vs 8.22%,P=0.015).High preoperative fasting plasma glucose[DFS:Hazard ratio(HR)=2.684,P<0.001;OS:HR=2.105,P=0.019;CRR:HR=2.214,P=0.005]and glycosylated hemoglobin levels(DFS:HR=2.344,P=0.006;OS:HR=2.119,P=0.021;CRR:HR=2.449,P=0.009)indicated significantly poor prognosis and high CRR,while T2DM history did not(DFS:HR=1.178,P=0.327;OS:HR=0.933,P=0.739;CRR:HR=0.997,P=0.581).CONCLUSION Increased preoperative fasting plasma glucose and glycosylated hemoglobin levels,but not T2DM history,were identified as risk factors associated with poor postoperative outcomes and high CRR in patients with stage Ⅲ CC.

N-Glycosylated type Ⅱ collagen peptides as therapeutic saccharide vaccines for rheumatoid arthritis

The interaction among type Ⅱ collagen(CⅡ),human DR4 major histocompatibility complex type Ⅱ molecule(MHC Ⅱ)and T-cell receptor(TCR)is associated with the development of rheumatoid arthritis(RA).The activation of T cells can be reduced through exposure to modified CⅡ(263-272)glycopeptide fragment via competitive inhibition with self-antigen.In this work,30 peptides based on the sequence of CⅡ(263-272)were prepared and evaluated for their binding to DR4 protein by surface plasmon resonance(SPR)assay.The effect on the secretion of pro-inflammatory factors by the spleen cells in collagen induced rheumatoid arthritis(CIA)mouse was also investigated.Two N-glycosylated CⅡ peptides were identified to have strong binding to the human recombinant DR4 protein and weak proinflammatory effect.These glycopeptides could be developed as therapeutic saccharide vaccines for the treatment of rheumatoid arthritis(RA).

Gut microbiome:A revolution in typeⅡdiabetes mellitus

TypeⅡdiabetes mellitus(T2DM)has experienced a dramatic increase globally across countries of various income levels over the past three decades.The persistent prevalence of T2DM is attributed to a complex interplay of genetic and environmental factors.While numerous pharmaceutical therapies have been developed,there remains an urgent need for innovative treatment approaches that offer effectiveness without significant adverse effects.In this context,the exploration of the gut microbiome presents a promising avenue.Research has increasingly shown that the gut microbiome of individuals with T2DM exhibits distinct differences compared to healthy individuals,suggesting its potential role in the disease’s pathogenesis and progression.This emerging field offers diverse applications,particularly in modifying the gut environment through the administration of prebiotics,probiotics,and fecal microbiome transfer.These interventions aim to restore a healthy microbiome balance,which could potentially alleviate or even reverse the metabolic dysfunctions associated with T2DM.Although current results from clinical trials have not yet shown dramatic effects on diabetes management,the groundwork has been laid for deeper investigation.Ongoing and future clinical trials are critical to advancing our understanding of the microbiome’s impact on diabetes.By further elucidating the mechanisms through which microbiome alterations influence insulin resistance and glucose metabolism,researchers can develop more targeted interventions.The potential to harness the gut microbiome in developing new therapeutic strategies offers a compelling prospect to transform the treatment landscape of T2DM,potentially reducing the disease’s burden significantly with approaches that are less reliant on traditional pharmaceuticals and more focused on holistic,systemic health improvements.

基于Cre-loxP重组酶系统构建肺泡Ⅱ型上皮细胞特异性敲除SENP1基因小鼠

背景:前期在体外成功构建了SENP1基因沉默的人肺泡上皮细胞系,在细胞水平上研究了SENP1在高氧性肺损伤中的作用。目的:基于Cre-loxP重组酶系统构建肺泡Ⅱ型上皮细胞特异性敲除SENP1基因小鼠模型。方法:将SENP1^(flox/-)小鼠自交得到SENP1^(flox/flox)和SENP1^(flox/-)小鼠;将Sftpc-Cre^(+/+)小鼠与野生型小鼠交配获得更多的Sftpc-Cre^(+/-)小鼠。将Sftpc-Cre^(+/+)或子代Sftpc-Cre^(+/-)小鼠与SENP1^(flox/-)或子代SENP1^(flox/flox)小鼠进行杂交,获得SENP1^(flox/-)Sftpc-Cre^(+/-)双杂合小鼠。将SENP1^(flox/-)Sftpc-Cre^(+/-)小鼠与SENP1^(flox/flox)小鼠杂交,获得SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠。剪鼠尾提取基因组DNA,行PCR扩增,扩增产物经琼脂糖凝胶电泳确定小鼠基因型。取SENP1^(flox/flox)和SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠肺组织行免疫荧光双标实验及Western blot以验证SENP1敲除效果;取SENP1^(flox/flox)和SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠心、肝、肺、肾组织行苏木精-伊红染色以观察两组小鼠各脏器的组织形态。结果与结论:琼脂糖凝胶电泳正确筛选出SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠。免疫荧光双标实验显示,与SENP1^(flox/flox)小鼠相比,SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠肺组织中SENP1的平均荧光强度降低(P<0.01),且SENP1和Sftpc未见明显共定位(P<0.01)。Western blot结果显示,与SENP1^(flox/flox)小鼠相比,SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠肺组织中SENP1蛋白表达降低(P<0.001)。苏木精-伊红染色结果显示SENP1^(flox/flox)和SENP1^(flox/flox)Sftpc-Cre^(+/-)小鼠的心、肝、肺和肾脏组织形态无明显改变。该研究利用Cre-loxP重组酶系统成功构建了肺泡Ⅱ型上皮细胞特异性敲除SENP1基因小鼠,为后续研究SENP1基因在以肺泡Ⅱ型上皮细胞为主要损伤细胞的肺疾病如支气管肺发育不良、特发性肺纤维化中的作用提供了良好的工具。

Discovery of angucyclinone polyketides from marine actinomycetes with a genomic DNA-based PCR assay targeting type Ⅱ polyketide synthase

Angucyclinones are aromatic polyketides produced by type Ⅱ polyketide synthases（PKS） and are mainly found in terrestrial actinomycetes. To discover more angucyclinones from marine actinomycetes, a genomic DNA-based PCR assay targeting type Ⅱ polyketide synthases was performed. Among the 167 marine actinomycetes strains screened, twelve strains were identified as the ＂positive＂ strains possessing type Ⅱ PKS-encoding genes based on the sequencing of PCR products. One of the 12 ＂positive＂ strains, Streptomyces sp. PKU-MA00218 was selected for the large-scale fermentation based on the HPLC and TLC analysis. Four angucyclinones, 6-deoxy-8-O-methylrabelomycin（1）, 8-O-methylrabelomycin（2）, 8-O-methyltetrangulol（3）, C-ring cleavage product of angucyclinone C（4）, were isolated and their structures were elucidated based on spectroscopic analyses. The isolation of angucyclinones 1–4 highlights the power of genome mining technologies based on biosynthetic knowledge in natural products discovery.