Analysis of epidemic characteristics and related factors of norovirus in diarrhea patients in Guangxi, 2015-2020 / 中国热带医学

@#Abstract: Objective　To analyze the epidemiological characteristics and related factors of norovirus in Guangxi from 2015 to 2020, and to provide scientific recommendations for norovirus prevention and control. Methods The foodborne diseases surveillance data were collected from 11 sentinel hospitals through the National Foodborne Disease Monitoring and Reporting System from 2015 to 2020. R software with version 4.0.3 was used for descriptive and statistical analysis, including epidemic curve, chi-square test, and trend chi-square and so on. Logistic regression was used to analyze norovirus-related factors, OR values and 95% confidence intervals were calculated respectively with the statistical test level of P<0.05. Results There were 1 008 norovirus cases detected, with a detection rate of 12.75% (1 008/7 903). Children with age less than 5 years (OR=1.43, 95%CI: 1.13-1.82) and patients at age 20-45 (OR=1.45, 95%CI: 1.13-1.87) were high risk population. The detection rate was higher in autumn (OR=1.29, 95%CI: 1.08-1.53) but lower in summer (OR=0.67, 95%CI: 0.55-0.80). In addition, the tourist area (Guilin City) presented a higher detection rate than other areas (OR=1.41, 95%CI: 1.10-1.80). Aquatic products (OR=1.40, 95%CI: 1.03-1.91), meat and dairy products (OR=1.31, 95%CI: 1.06-1.61) were high-risk foods for norovirus infection. The prevention and control policies of COVID-19 can reduce the possibility of norovirus by 61% (OR=0.39, 95%CI: 0.31-0.49) showed a declining trend (Trend χ2=85.33, P<0.001). In addition, prolonged visit time can lead to 19%-23% decrease in the detection rate of norovirus (OR24-48 hours=0.81, 95%CI: 0.70-0.95; OR>48 hours=0.77, 95%CI: 0.63-0.93). Conclusions　The epidemic of norovirus presented seasonal and regional distribution in Guangxi with a declining detection rate trend in diarrhea patients during recent 6 years. Young children were high-risk population in infection norovirus. The intake of seafood can increase the risk of norovirus infection. The prevention and control policies of COVID-19 can sharply decrease the possibility of infection norovirus. The monitoring of key foods such as seafood should be strengthened, and the early screening of suspected cases should be taken. The norovirus monitoring should be improved to ensure the health of the population.

Intra-operative mapping and language protection in glioma / 中华医学杂志(英文版)

The demand for acquiring different languages has increased with increasing globalization. However, knowledge of the modification of the new language in the neural language network remains insufficient. Although many details of language function have been detected based on the awake intra-operative mapping results, the language neural network of the bilingual or multilingual remains unclear, which raises difficulties in clinical practice to preserve patients' full language ability in neurosurgery. In this review, we present a summary of the current findings regarding the structure of the language network and its evolution as the number of acquired languages increased in glioma patients. We then discuss a new insight into the awake intra-operative mapping protocol to reduce surgical risks during the preservation of language function in multilingual patients with glioma.

Clinical application of laser in crown lengthening / 华西口腔医学杂志

Crown lengthening is one of the most common surgeries in clinical practice. Under the premise of ensuring the biologic width, the adequate crown is exposed by resecting the periodontal soft tissue and (or) hard tissue to meet the prosthodontic and (or) aesthetic requirements. Considering the various advantages of oral laser, such as safe, precise, minimally invasive and comfort, laser has become a promising technology which can be used to improve the traditional crown lengthening. In this review, the principles and characteristics of laser application in crown lengthening, especially in the minimally invasive or flapless crown lengthening will be reviewed. Its pros and cons will also be discussed.

Rationale and Study Design for a Single-Arm Phase IIa Study Investigating Feasibility of Preventing Ischemic Cerebrovascular Events in High-Risk Patients with Acute Non-disabling Ischemic Cerebrovascular Events Using Remote Ischemic Conditioning / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Acute minor ischemic stroke (AMIS) or transient ischemic attack (TIA) is a common cerebrovascular event with a considerable high recurrence. Prior research demonstrated the effectiveness of regular long-term remote ischemic conditioning (RIC) in secondary stroke prevention in patients with intracranial stenosis. We hypothesized that RIC can serve as an effective adjunctive therapy to pharmacotherapy in preventing ischemic events in patients with AMIS/TIA. This study aimed to investigate the feasibility, safety, and preliminary efficacy of daily RIC in inhibiting cerebrovascular/cardiovascular events after AMIS/TIA.</p><p><b>METHODS</b>This is a single-arm, open-label, multicenter Phase IIa futility study with a sample size of 165. Patients with AMIS/TIA receive RIC as an additional therapy to secondary stroke prevention regimen. RIC consists of five cycles of 5-min inflation (200 mmHg) and 5-min deflation of cuffs on bilateral upper limbs twice a day for 90 days. The antiplatelet strategy is based on individual physician's best practice: aspirin alone, clopidogrel alone, or combination of aspirin and clopidogrel. We will assess the recurrence rate of ischemic stroke/TIA within 3 months as the primary outcomes.</p><p><b>CONCLUSIONS</b>The data gathered from the study will be used to determine whether a further large-scale, multicenter randomized controlled Phase II trial is warranted in patients with AMIS/TIA.</p><p><b>TRIAL REGISTRATION</b>ClinicalTrials.gov, NCT03004820; https://www.clinicaltrials.gov/ct2/show/NCT03004820.</p>

Cloning of Guamerin gene in Whitmania pigra and its spatio-temporal expression analysis after ingestion / 中国中药杂志

The present study cloned wpGuamerin gene from a non-bloodsucking leech (Whitmania pigra), and the bioinformatics analysis of the sequence was performed. Additionally, the effects of feeding duration on the expression profile of the wp Guamerin gene were explored. The results showed that its sequence consisted of 295 nucleotides encoding a peptide of 83 amino acids(Genbank: KX768545), and its relative molecular weight is 9 145.95 Da. wp Guamerin does not encode proteins with a signal peptide, belonging to the hydrophilic protein. Its secondary structure is mainly composed of α-helix, extending chain, folding and random curl. Its similarity with other blood-sucking leeches ranges from 29% to 65%. The results revealed that wpGuamerin mRNA was detected higher expression in muscle than in salivary glands of Wh. pigra, and did not expressed in ingluvies and intestine. Its expression in muscle and salivary glands showed a single peak curve after feeding and the peak was observed in the 1st and 3rd after feeding, respectively. In summary, wp Guamerin in Wh. pigra is a small molecule polypeptide protein and is different from the Guamerin in blood-sucking leeches. wpGuamerin does not express in the digestive tract of Wh. pigra, and mainly express in muscle. Feeding behavior would stimulate the expression of wpGuamerin gene in muscle and salivary glands, but not in digestive tract.

Effect of Astragali Radix on growth, immunity and related gene expression of Whitmania pigra / 中国中药杂志

To explore the effect and mechanism of Astragali Radix on growth and immunity of Whitmania pigra, 0, 0.01%, 0.03%, 0.05%, 0.07%, 0.09% of Astragali Radix were added to the daily feeding of Wh. pigra. After 60 days of feeding, the growth performance, activities of digestive enzyme and anti-reverse enzyme, inner quality, the expression levels of GH, IGF-1 and digestive enzyme-related genes were measured. Meanwhile, the effects of heat stress on the living conditions of Wh. pigra were observed and counted, and the expression levels of HSP70 and immune related genes were measured. The results showed that the final weight, weight gain rate, specific growth rate, activities of digestive enzyme and anti-reverse enzyme, the expression levels of GH, IGF-1 and digestive enzyme-related genes in the Astragali Radix group were higher than those in the control group, and with the increase of Astragali Radix concentration, the above-mentioned indexes increased initially and then decreased, and significantly higher in the 0.05% of Astragali Radix group than in the other groups (<0.05). There was no significant difference in the inner quality of Wh. pigra between the Astragali Radix and control groups. The survival rate of Wh. pigra was negatively correlated with heat stress treatment duration. With the prolongation of heat stress treatment duration, the expression levels of HSP70 and immune related genes were increased first and then decreased, and peaked at 24 h. The survival rate and the expression levels of HSP70 and immune related genes in the Astragali Radix group were higher than those in the control group, and was significantly higher in the 0.05% of Astragali Radix group than in the other groups (<0.05). In conclusion, Astragali Radix can increase the activities of digestive enzyme and anti-reverse enzyme, the expression levels of related genes, growth performance, and immunity to heat stress of Wh. pigra. It is suggested to add 0.05% of Astragali Radix in the actual production of Wh. pigra to improve the production profit.

Different arousal modes of hibernating Whitmania pigra / 中国中药杂志

To study the suitable arousal modes of hibernating Whitmania pigra, the biological characteristics, activity of amylase, lipase, and protease as well as morphologic structure of digestive tract were investigated by direct observational method and 3, 5-dinitrosalicylic acid colorimetry, p-nitrophenyl palmitate ester（p-NPP）colorimetry, folin-phenol and histological methods. The results revealed that Wh. pigra activity was increased with increases of the water temperature and prolonging treating duration. Except for the feeding groups of direct arousal mode at 24 h and 48 h, none of the other Wh. pigra groups died. Compared with that of normal groups, the digestive tract structure of hibernating Wh. pigra was looser and the mucosal folds of craw were more sparse. No obvious recovery was observed for the structure of the digestive tract before 48 h of direct arousal mode or the 5th day of 15 °C gradient arousal mode. The mucosal folds of craw increased and the muscularis were incrassated after 72 h of direct arousal mode or the 8th day of 20 °C gradient arousal mode, that indicated the tissue structure was approximately restored to the normal state. The digestive enzyme activities were increased with prolonging treating duration. And the feeding groups recovered faster than that of the no feeding groups. Additionally, the enzyme activities of feeding groups were significantly higher than that of no feeding groups (<0.05) and approximately restored to the normal level after 48 h in the direct arousal mode or 20 °C in the gradient arousal mode. In conclusion, both of the two modes can be applied to the arouse of hibernating Wh. pigra, and it should be fed when the temperature is recovered to 15 °C or 20 °C at 2 °C·d⁻¹ in the gradient arousal mode after 72 h in the direct arousal mode to reduce the death ratio and improve effectively the economic profit of Wh. pigra aquaculture.

Effects of Cu²⁺ enrichment and release on growth， internal quality and relative gene expression of Whitmania pigra / 中国中药杂志

The present study explored the effects of Cu²⁺enrichment and release on the growth and internal quality of Whitmania pigra, and the regularity of enrichment and release in different tissues of Wh. pigra. In the range of safe concentration(SC), a certain concentration of Cu²⁺ was added to the Wh. pigra for 50 days, and stopped adding for another 50 days. The growth index of Wh. pigra, Cu²⁺ content in different tissues, and the internal quality were determined. The results showed that the average body weight of Wh. pigra in 0.014 mg·L⁻¹ of Cu²⁺ group was significantly higher than that in control group during the experimental period (<0.05), and the mortality rate was lower than that in the control group. The specific growth rate, digestive enzyme activity, growth and digestive enzyme related gene expression of Wh. pigra in Cu²⁺ group were significantly higher than that in the control group (<0.05) during the early 40 days of enrichment, and there was no significant difference in the release period. In Cu²⁺ group, the expression of immune enzyme and immune enzyme related gene of Wh. pigra increased first and then decreased compared with control group (<0.05). The ability of enriched Cu²⁺ in different tissues of Wh. pigra was digestive tract>muscle>skin. The ability of release Cu²⁺ was muscle>digestive tract>skin. There was no significant difference in the internal quality and hirudin gene expression between Cu²⁺ group and control group. In conclusion, Cu²⁺ can improve the expression of digestive enzymes, immune enzyme and related genes of Wh. pigra, promote the growth of Wh. pigra and enhance their immunity, but it doesn't affect the internal quality of Wh. pigra. The Wh. pigra can completely release Cu²⁺ within 30 days.

Preliminary study on pathogen of Whitmania pigra disease in high temperature environment / 中国中药杂志

In this paper, on the contrast of healthy leech, the bacterial diversities were analyzed by 16S rDNA sequence analysis of the bacteria of muscle and intestinal tract of Whitmania pigra, the environment water and sediment of cultivating the diseased Wh. pigra in high temperature by high-throughput sequencing to determine the possible pathogenic bacteria of bacterial diseases of Leech in high temperature. The results showed that the original sequence reached over 83 000, and the effective sequences accounted for more than 87%. The GC contents ranged from 52% to 54% and the bacterial diversities were abundant. Bacterial relative abundance analysis showed that the bacterial content of Proteobacteria, Bacteroidetes, and Firmicutes was the most abundant in all treatments. Compared with healthy leech muscles and intestines, the muscle and intestinal tract of pathogenic leech relative abundance of Bacteroides, Pseudomonas, and Desulfovibrio was significantly increased, and it was abundant in water and sediment of diseased leeches, Lead to the possibility that the pathogenic bacteria of this bacterial disease may be Bacteroides, Pseudomonas, Desulfovibrio.

Recurrent convulsion and pulmonary infection complicated by psychomotor retardation in an infant / 中国当代儿科杂志

A 4-month-old girl developed convulsion in the neonatal period, which was focal motor seizures in the initial stage and later became spasm and tonic spasm. And the girl also had psychomotor retardation and recurrent pulmonary infection. Electroencephalography showed hypsarrhythmia, normal results were obtained from cranial magnetic resonance imaging, cerebrospinal fluid examination, and urine organic acid analysis, as well as the spectral analyses of blood ammonia, blood lactic acid, blood amino acids, and acylcarnitines. Gene detection revealed a de novo heterozygous mutation, c.607G>A (p.G203R) , in GNAO1. The girl was then diagnosed with GNAO1-associated early infantile epileptic encephalopathy (EIEE type 17). The seizures were well controlled by topiramate and vigabatrin, but there was no improvement in psychomotor development. She also suffered from recurrent pulmonary infection and died at the age of 12 months due to severe pneumonia. For children with unexplained early infantile epileptic encephalopathy, GNAO1 gene mutations should be considered and genetic tests should be performed as early as possible. Recurrent pulmonary infection should also be taken seriously.

Effects of Qibao Meiran Oral Liquid on SOD activity and carbonyl protein content in brain tissue of mice / 中成药

AIM To observe the effects of Qibao Meiran Oral Liquid (Polygoni multiflori Radix Praeparata,Angelicae sinensis Radix,Psoraleae Fructus,etc.) on learning and memory function,hippocampus tissue pathological morphology,SOD activity and carbonyl protein content in SAMP8 mice.METHODS Twenty-seven SAMP8 mice were randomly and equally divided into model control group,donepezil hydrochloride group and Qibao Meiran Oral Liquid group.Another nine SAMR1 mice were selected as normal control group.Mice were given successive intragastric administration for 60 days.On the 56th day,the passive avoidance test was adopted,and the learning and memory capacities were determined after 5 d;The pathological morphology was observed by HE staining;ELISA assay was used to detect the activity of SOD and the content of carbonyl protein in brain tissue.RESULTS Compared with the model control group,the escape latency of mice in the Qibao Meiran Oral Liquid group was significantly prolonged,and the number of errors decreased significantly (P ＜0.01);the pathological morphology of hippocampus tissue was significantly improved;SOD activity increased significantly,and carbonyl protein content decreased significantly (P ＜ 0.01).CONCLUSION Qibao Meiran Oral Liquid can not only improve the learning and memory function of SAMP8 mice,but also reduce the degree of hippocampus tissue degenerative disease.

Clinical Features of Patients with Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorders / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Neuromyelitis optica spectrum disorder (NMOSD) was long believed to be an aggressive form of multiple sclerosis (MS). This study aimed to describe the clinical features of patients with MS and NMOSD to assist in differential diagnoses in clinical practice.</p><p><b>METHODS</b>Data including the patients' serum and cerebrospinal fluid (CSF) tests, image findings, and clinical information from 175 patients with MS or NMOSD at Xuanwu Hospital, Capital Medical University from November 2012 to May 2014 were collected and analyzed retrospectively. An enzyme-linked immunosorbent assay was performed to detect the myelin oligodendrocyte glycoprotein (MOG) autoantibodies in CSF and serum. Cell-based assays were used to detect aquaporin-4-antibody (AQP4-Ab). The Chi-square test was used to compare the categorical variables. Wilcoxon rank sum test was performed to analyze the continuous variables.</p><p><b>RESULTS</b>Totally 85 MS patients (49%) and 90 NMOSD patients (51%) were enrolled, including 124 (71%) women and 51 (29%) men. Fewer MS patients (6%) had autoimmune diseases compared to NMOSD (19%) (Δ2 = 6.9, P < 0.01). Patients with NMOSD had higher Expanded Disability Status Scale scores (3.5 [3]) than MS group (2 [2]) (Z = -3.69, P < 0.01). The CSF levels of white cell count and protein in both two groups were slightly elevated than the normal range, without significant difference between each other. Positivity of serum AQP4-Ab in NMOSD patients was higher than that in MS patients (MS: 0, NMOSD: 67%; Δ2 = 63.9, P < 0.01). Oligoclonal bands in CSF among NMOSD patients were remarkably lower than that among MS (MS: 59%, NMOSD: 20%; Δ2 = 25.7, P < 0.01). No significant difference of MOG autoantibodies was found between the two groups.</p><p><b>CONCLUSION</b>The different CSF features combined with clinical, magnetic resonance imaging, and serum characteristics between Chinese patients with MS and NMOSD could assist in the differential diagnosis.</p>

Studies on hibernation pivotal temperature of Whitmania pigra / 中国中药杂志

The biological characteristics, oxygen consumption, oxygen consumption rate, and activities of amylase, lipase and protease of Whitmania pigra at different temperature were studied by using direct observational method, the still water method and 3, 5-dinitrosalicylic acid colorimetry, right-nitrophenyl palmitate ester（ρ-NPP）colorimetry and folin-phenol method.The results revealed that with decreasing water temperature, the daily activity and the daily feeding ration were decreased. As the temperature was lowered to 4 ℃, the head and tail of Wh.pigra curved, showing a crescent-shape without feeding and daily activity. Oxygen consumption, oxygen consumption rate and digestive enzyme activities reduced along with temperature drops. The downward trend slowed below 10 ℃, began to stabilize below 4 ℃ and doesn't change with the decrease of temperature since then. During the 40 days treatment at 4 ℃, the changes of amylase were not significant, the lipase and protease activity decreased at the 20th day, and the lipase showed an slightly increase after the decrease and finally remained at a low level.In conclusions, the pivotal temperature of hibernation of Wh.pigra is 4 ℃ and the crescent shape can be considered as a symbol of hibernation.

Effects of stocking density and exchanging water frequency on growth and inner quality of Whitmania pigra / 中国中药杂志

The effects of stocking density and exchanging water frequency on growth, digestive enzyme activity, anti-oxidative enzyme and inner quality of Whitmania pigra Whitman were evaluated with corresponding measures. The results showed that the eventual biomass, specific growth rate, gained weight rate, activities of amylase, lipase, protease, SOD, CAT, and ALP correlated positively with stocking density and negatively with exchanging water frequency (P<0.05). Exchanging water frequency had negative correlation with ammonia nitrogen, nitrite, and hydrogen sulfide while revealed positive correlation with dissolved oxygen in the water. Stocking density and exchanging water frequency showed no significant effects on the contents of moisture, total ash, and acid-insoluble ash. It suggested that the optimum stocking density was 7.5 million per hectare and the appropriate exchanging water interval was 72 h.

Effects of harvest and different processing methods on anti-thrombin activity of Poecilobdella manillensis / 中国中药杂志

The effects of harvest and different processing methods on the anti-thrombin activity of Poecilobdella manillensis were respectively studied. The indicators included processing methods (vacuum freeze drying, fresh homogenate, drying under sunlight, freezing, scalding, baking under different temperatures), different parts (entire body, cephalon, pygidium, exudate) and body weights (≤10, 10-20, 20-30, 30-40, ≥40 g). The anti-thrombin activities of P. manillensis with different processing methods were evaluated by direct anti-thrombin titration. The results indicated that the processing methods significantly affected the anti-thrombin activities of P. manillensis. Among the 11 groups, the anti-thrombin activity of P. manillensis processed with vacuum freeze drying (1 303.56 U•g⁻¹) was significantly highest than the other groups (P<0.05), and that processed with baking under 90 ℃ (15.44 U•g⁻¹) was the lowest. The anti-thrombin activity of the cephalon of P. manillensis (226.42 U•g⁻¹) was the highest, and that of the pygidium (102.12 U•g⁻¹) was lowest; the anti-thrombin activities for different body weights were significantly different (P<0.05); and among the five groups, the body weight of ≤10 g (328.86 U•g⁻¹) was the highest (P<0.05), and the body weight of ≥40 g (87.71 U•g⁻¹) was the lowest. In conclusion, harvest and different processing methods had a significant impact on the anti-thrombin activities of P. manillensis. In the study, for the optimal processing method for P. manillensis, the body weight between 20-30 g is recommended, and the vacuum freeze drying is preferred, which is followed by the drying under sunlight.

Expression of protein 4.1 family in melanoma cell lines and its effect on cell proliferation / 南方医科大学学报

<p><b>OBJECTIVE</b>To detect the expression of protein 4.1 family members in mouse melanoma cell lines and evaluate their effect on cell proliferation.</p><p><b>METHODS</b>PCR and Western blot were used to detected to the expression of protein 4.1 family members (4.1R, 4.1B, 4.1G, and 4.1N) at the mRNA and protein levels in B16 and B16-F10 cell lines. The expression plasmid vector pEGFP-N1-EPB41L3 carrying 4.1B gene sequence amplified from genomic RNA of mouse embryo fibroblasts was constructed and transiently transfected into mouse melanoma cells. The change in cell proliferation was assessed using MTT assay.</p><p><b>RESULTS</b>The mRNA and protein expressions of all the protein 4.1 family members, with the exception of 4.1B, were detected in both B16 and B16-F10 cells. Transfection of cells with the eukaryotic expression vector pEGFP-N1-EPB41L3 markedly inhibited cell proliferation as compared with the non-transfected cells.</p><p><b>CONCLUSION</b>The eukaryotic expression vector carrying EPB41L3 sequence is capable of inhibiting the proliferation of mouse melanoma B16 and B16-F10 cells.</p>

Progress of study on p62 and protein degradation pathways / 生理学报

The p26, a multifunctional ubiquitin-binding protein, has been proposed to be involved in protein degradation as a component within the ubiquitin-proteasome and autophagy-lysosome systems. As a scaffolding protein with several different kinds of protein-protein interaction domains, p62 mediates various cellular functions. Importantly, p62 plays a critical role in cell's selective autophagy and oxidative stress response, which are associated with the pathogenesis of several human diseases. In this review, we describe the structure of p62 and the mechanism of connection between p62 and ubiquitin-proteasome system/autophagy, so as to provide some perspectives on p62 research.

A Key Component Determination on Forming Fairy Tofu from the Leaf of Premna Puberula (Verbenaceae).

A key component of Fairy Tofu from leaves of Premna puberula Pamp. was determined by immediate constituent analysis and prescription dismantlement analysis. The results showed that pectin in leaves of P. puberula was the key component as forming Fairy Tofu. It was because the highest component was pectin in Fairy Tofu except water, the pectin extracting directly from the leaves of P. puberula could be formed the jelly like Fairy Tofu, and the leaves which pectin was hydrolyzed by pectinase could not be made Fairy Tofu.

Genetic polymorphism of surfactant protein A in neonatal respiratory distress syndrome / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the characteristics of gene expression of surfactant protein A in Chinese premature infants and the association between surfactant protein A and the risk of neonatal respiratory distress syndrome (RDS).</p><p><b>METHODS</b>Vein-blood samples (2 mL) from 18 Chinese premature infants with RDS and 28 controls were assayed for SP-A genotypes 6A2, 6A3, 1A0 and 1A1 by SSCP.</p><p><b>RESULTS</b>The frequency of allele distribution of SP-A1 allele 6A2 and 6A3 was 0.50 and 0.056 respectively in the RDS group and was 0.214 and 0.107 in the control group. Compared with the controls, SP-A1 allele 6A2 was over-represented in the RDS group (P<0.05). In contrast, SP-A1 allele 6A3 tended to be under-represented in the RDS group but there was no statistical difference when compared with the controls. The frequency of allele distribution of SP-A2 allele 1A0 and 1A1 was 0.722 and 0.667 respectively in the RDS group and was 0.679 and 0.821 respectively in the control group. There were no significant differences in the distribution frequency of SP-A2 allele 1A0 and 1A1 between the two groups. In the infants born at gestation >32 weeks, SP-A1 allele 6A2 was over-represented in the RDS group compared with the control group (frequency: 0.56 vs 0.15; P<0.05).</p><p><b>CONCLUSIONS</b>The frequency of SP-A1 allele 6A2 and 6A3 was low, in contrast, the frequency of SP-A2 allele 1A0 and 1A1 was high in normal Chinese premature infants. SP-A1 allele 6A2 may be a susceptible gene for RDS.</p>

Soluble expression of recombinant human apoliprotein A-I-Milano in Escherichia coli / 生物工程学报

Apolipoprotein A-I-Milano(AIM), a natural variant, not only inhibits the initiation and progression of atherosclerosis, but also makes the preexisting atherosclerotic lesions regress. AIM gene, at which N-terminal codens were optimized, was subcloned into the expression vector of pET22b. Recombiant plasmids were transformed into E. coli strain BL21 (DE3) and induced with IPTG. The expressed apoliprotein A-I-Milano was soluble in E. coli and was about 38% of total cell lysate. Purified by Butyl Sepharose 4F. F hydrophobic chromatography and Q Sepharose H.P. anion exchange chromatography, followed by ultrafiltration with Vivaspin 20 (30 000MW), AIM monomer was obtained in a purity of more than 95%. Activity assay of binding of AIM monomer to lipid indicates that association of AIM monomer with DMPC is slower than normal apoA-I but DMPC number associated by AIM monomer is more than by apoA-I. This results will be important for studying structure, function of AIM, specially clinical application.