The recombinant fusion protein staphylokinase-hirudin(rSFH) was purified from the high density-fermented engineered E.coli by means of ion-exchange chromatography (IEC) and gel filtration (GF). The purity of rSFH reached to more than 98% determined by RP-HPLC and SDS-PAGE, and the yield was up to 0.7g per liter of fermentation broth. The analysis of homologous dimmer of rSFH appeared during the purification and calculation of the surface hydrophobic area had been carried out by means of hydrophobic chromatography and MALD-TOF. The influence of sodium chloride and temperature on the behavior of rSFH reversible dimerization was analyzed by high performance sized- exclusive chromatography(HPSEC). It is concluded that the hydrophobic interaction played an important role in the reversible dimerization of rSFH.

To combine the fibrinolytic with anticoagulant activities for therapy of thrombotic deseases, a fusion protein made of tissue-type plasminogen activator (t-PA) and hirudin was constructed and expressed in chia pastoris. To improve thrombolytic properties of t-PA and reduce bleeding side effect of hirudin, FXa-recognition sequence was introduced between t-PA and hirudin molecules.The anticoagulant activity of hirudin can be target-released through cleavage of FXa at thrombus site. t-PA gene and hirudin gene with FXa-recognition sequence at its 5'-terminal were obtained by RT-PCR and PCR respectively. The fusion protein gene was cloned into plasmid pIC9K and electroporated into the genome of Pichia pastoris GS115. The expression of fusion protein was induced by methanol in shaking flask and secreted into the culture medium. Two forms of the fusion protein, single-chain and double-chain linked by a disulfide bond (due to the cleveage of t-PA at Arg275-Ile276), were obtained. The intact fusion protein retained the fibrinolytic activity but lacked any anticoagulant activity. After cleavage by FXa, the fusion protein liberated intact free hirudin to exert its anticoagulant activity. So, the fusion protein is a bifunctional molecule having good prospect to develop into a new targeted therapeutic agent with reduced bleeding side effect for thrombotic diseases.
Animals ; Cloning, Molecular ; Electroporation ; Hirudins ; biosynthesis ; genetics ; Humans ; Pichia ; genetics ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Tissue Plasminogen Activator ; biosynthesis ; genetics

OBJECTIVETo study the factors affecting the management and treatment of immigrant workers with tuberculosis, to determine the most effective measures and to provide an academic basis for tuberculosis control and prevention strategies targeting the immigrant population.

METHODSA self-designed questionnaire was administered to 1364 immigrant workers with tuberculosis (study group) and 436 local residents (control group) with tuberculosis.

RESULTSWhether a patient's tuberculosis status was discovered or not was related to the medical facilities initially visited, job mobility, and the individual worker's economic condition. The percentage of cases discovered was relatively low among those who made their first visit to a private clinic (39.0%), and 58.4% (796) of immigrant workers delayed their first consultation mainly due to neglecting symptoms (55.9%, 445), subjective perception of symptoms being not severe enough (19.3%, 154) to visit a physician and the inconvenience of visiting a hospital because of its being far away from home (15.8%, 47). As comparing immigrant workers with local residents, the differences of the delay reason between the two groups were statistically significant (chi(2) = 21.49, P < 0.01). And 39.9% (544) of immigrant workers and 49.1% (214) of local residents had had late confirmation. The differences of the delay reasons between the two groups were insignificant (chi(2) = 7.31, P = 0.293). And 17.6% (240) patients of immigrant workers and 13.1% (57) patients of local residents did not keep to their drug regimens in a timely fashion. The differences of the reasons between the two groups were insignificant (chi(2) = 6.66, P > 0.05). And 77.5% (1057) of immigrant workers and 31.8% (138) of local residents were considered that taking medicine in supervision spot might have impact on their lives and work. The differences of the reasons between the two groups were significant (chi(2) = 9.71, P < 0.05). All 79.2% (1080) of immigrant workers and 63.3% (276) of local residents did not obtain medicine according to prescriptions. The differences of reasons between the two groups were statistically significant (chi(2) = 24.84, P < 0.01). And 51.2% (699) of immigrant workers and 46.1% (201) of the registered population did not follow up with doctors' directions for lab tests. The differences of the reasons between the two groups were insignificant (chi(2) = 3.26, P > 0.05).

CONCLUSIONThe influential factors in tuberculosis management and treatment were complex. Prevention strategies should focus on health education and promotion activities to improve awareness in seeking medical services. Also, developing and standardizing reference mechanisms for patients, and alleviating the economic burden of the workers will be critical to reduce the tuberculosis incidence.

China ; epidemiology ; Factor Analysis, Statistical ; Humans ; Transients and Migrants ; Treatment Outcome ; Tuberculosis, Pulmonary ; epidemiology ; prevention & control ; therapy ; Urban Population

OBJECTIVEIn this study, a growing rat model of zinc deficiency was established to investigate the effect of zinc deficiency on intestinal mucosal morphology and digestive enzyme activity as well as to provide a scientific basis for zinc supplementation therapy in patients with diarrhea.

METHODThree-week-old weaned Sprague-Dawley male rats (n = 30) were randomly divided into 3 groups with 10 in each: rats in the control group (ZA) were fed with a normal diet containing 30 µg/g zinc; rats in the zinc deficient group (ZD) were fed with a zinc-deficient diet containing 0.4 µg/g zinc (refer to AIN-76 formula); and rats in the paired fed group (PF) were fed with a normal diet, but the food intake was limited to intake of rats in ZD group in the previous day. All rats were provided with deionized water for drinking. Their body weight was measured and the food intake during the previous day was recorded early in the morning of the following day. Symptoms of zinc deficiency, such as anorexia, diarrhea, dermatitis, and growth retardation, were observed. Two weeks later, the rats were sacrificed and serum zinc concentration was measured. Jejunal mucosa was taken for biopsy and was stained with hematoxylin and eosin (HE). The height ratio of the jejunal mucosal villi and crypts was measured. In addition, the activity of lactase in the jejunal mucosal brush border, γ-glutamyl peptidase (GGT), and aminopeptidase N (APN) were measured.

RESULTThe average weight of the rats in the ZA, ZD, and PF groups at the beginning of the experiment was (67.4 ± 5.3) g, (64.7 ± 4.8) g, and (66.5 ± 4.1) g, respectively, and the average daily food intake was (11.2 ± 1.0) g, (11.6 ± 1.6) g, and (11.2 ± 1.4) g, respectively. The intergroup differences were not significant. On the 7(th) day of experiment, no significant differences in average food intake were observed between the ZD group and the ZA and PF groups, but the average body weight in the ZD group was significantly lower than that in the ZA and PF groups (P < 0.01). At the end of the experiment (2 weeks), the average weight in the ZD group (112.0 ± 11.5) g was significantly lower than that in the ZA (164.0 ± 15.9) g and PF groups (137.5 ± 16.2) g. The average food intake in the ZD group (13.4 ± 5.1) g was significantly lower than that in the ZA group (18.2 ± 2.4) g (P < 0.01). Serum zinc level in the ZD group (733 ± 231) µg/L was significantly lower than that in the ZA (1553 ± 159) µg/L and PF groups (1457 ± 216) µg/L (P < 0.01). The height ratio of jejunal mucosa villus and crypt in the ZA, ZD, and PF groups was 2.98 ± 0.5, 2.77 ± 0.5, and 2.81 ± 0.7, respectively, and lactase activity was (26.1 ± 15.0) U/mg, (27.4 ± 12.8) U/mg, and (40.8 ± 18.5) U/mg, respectively, without significant intergroup differences. The GGT activity in the jejunal mucosa in the ZD group (12.7 ± 6.5) U/g was significantly lower than that in the ZA (19.1 ± 10.4) U/g and PF groups (18.5 ± 7.7) U/g, but the difference was not significant. The activity of APN in the jejunal mucosa in the ZD group (25.5 ± 7.5) U/g was significantly lower than that in the ZA (48.7 ± 16.8) U/g and PF groups (43.9 ± 14.5) U/g (P < 0.01).

CONCLUSIONZinc deficiency can cause loss of appetite, weight loss, and decreased activity of peptidase in the jejunal mucosal brush border. Zinc deficiency has little effect on the height ratio of the villus and crypt and lactase activity, thereby indicating that zinc deficiency may first affect protein digestion and absorption.

Animals ; Intestinal Mucosa ; enzymology ; metabolism ; pathology ; Jejunum ; metabolism ; pathology ; Lactase ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Zinc ; deficiency

OBJECTIVETo evaluate the roles of enteric nervous system neurotransmitters, nitric oxide (NO), substance P (SP) and vasoactive intestinal polypeptide (VIP), and interstitial cells of Cajal (ICC) in the colon in slow transit constipation in rats.

METHODSThirty-two healthy Wistar rats were randomly assigned to control and constipated groups. In the constipated group, the rats were daily administered with diphenoxylate (8 mg/kg) to develop slow transit constipation, while the control rats were fed with water. The number and the weight of fecal granule and the body weight of rats were recorded every 5 days for 90 days. Transit functions of intestinal movement were examined by an activated charcoal suspension pushing test one week after stopping the administration of diphenoxylate. The levels of NO and SP in the colonic mucosa were measured by nitrate reductase methods and ELISA respectively. The distribution of VIP and ICC positive cells confirmed with symbolic c-kit+ cells in the colonic wall were observed by immunohistochemical methods.

RESULTSThe daily number of fecal granule in the constipated group was significantly less than that in the control group (P<0.01). The mean weight of each fecal granule in the constipated group was significantly higher than that in the control group (P<0.01). The discharge time of the first granule of black faeces in the constipated group (430.2+/- 132.1 min) was significantly longer than that in the control group (337.2+/- 74.7 min; P<0.05). There were no significant differences in NO and SP levels and the density of VIP positive cells in the distal colonic segment between the two groups. The number of c-kit+ cells in the distal colonic wall in the constipated group was significantly reduced compared with that in the control group (P<0.05).

CONCLUSIONSThe reduction of ICC number in the distal colon may be contributed to the pathogenesis of slow transit constipation in rats.

Animals ; Body Weight ; Coiled Bodies ; Colon ; cytology ; innervation ; Constipation ; etiology ; Male ; Neurotransmitter Agents ; physiology ; Nitric Oxide ; analysis ; physiology ; Proto-Oncogene Proteins c-kit ; analysis ; Rats ; Rats, Wistar ; Substance P ; analysis ; physiology ; Vasoactive Intestinal Peptide ; analysis ; physiology

OBJECTIVETo investigate the risk factors for the development of congenital anal atresia in neonates.

METHODSA total of 70 neonates who were admitted to 17 hospitals in Foshan, China from January 2011 to December 2014 were enrolled as case group, and another 70 neonates who were hospitalized during the same period and had no anal atresia or other severe deformities were enrolled as control group. Univariate and multivariate logistic regression analyses were used to investigate the risk factors for the development of congenital anal atresia.

RESULTSThe univariate analysis revealed that the age of mothers, presence of oral administration of folic acid, infection during early pregnancy, and polyhydramnios, and sex of neonates showed significant differences between the case and control groups (P<0.05). The multivariate logistic regression analysis revealed that infection during early pregnancy (OR=18.776) and male neonates (OR=9.304) were risk factors for congenital anal atresia, and oral administration of folic acid during early pregnancy was the protective factor (OR=0.086).

CONCLUSIONSInfection during early pregnancy is the risk factor for congenital anal atresia, and male neonates are more likely to develop congenital anal atresia than female neonates. Supplementation of folic acid during early pregnancy can reduce the risk of congenital anal atresia.

Anus, Imperforate ; etiology ; Female ; Humans ; Infant, Newborn ; Logistic Models ; Male ; Pregnancy ; Risk Factors

Objective: To explore the application effects of feedforward control theory in the rollover bed treatment of mass patients with burn-explosion combined injury. Methods: A retrospective observational research was conducted. From June 13 to 14, 2020, 15 patients with severe burn-explosion combined injury caused by liquefied natural gas tank car explosion and conforming to the inclusion criteria were admitted to the Second Affiliated Hospital of Zhejiang University School of Medicine. There were 13 males and 2 females, aged 33-92 (66±17) years. All the patients were treated with rollover bed from 48 h post admission, and the feedforward control theory was introduced, including establishing a special feedforward control management team for rollover bed, clarifying the duties of the medical staff in the rollover bed treatment of patients, implementing the cooperation strategy of multidisciplinary physician, training and examining for 80 nurses in the temporarily organized nurse team in the form of "rollover bed workshop", and formulating the checklist and valuation list of rollover bed treatment for continuous quality control. The frequency and the total number of turning over, and successful rate of one-time posture change with the rollover bed of patients within 30 days of admission were recorded, the occurrences of adverse events caused by improper operation for the rollover bed during the treatment were observed, including respiratory and cardiac arrests, treatment interruption, unplanned extubation, bed falling, and skin graft displacement. The lowest levels of arterial partial pressure of oxygen (PaO₂) and arterial partial pressure of carbon dioxide (PaCO₂), the number of patients with oxygenation index>300 mmHg (1 mmHg=0.133 kPa), and the occurrence of acute respiratory distress syndrome (ARDS) of patients within 2 days of admission and on the 30^th day of admission were recorded. Results: Within 30 days of admission, the patients were turned over with the rollover bed for 2 to 6 times each day, with a total of 1 320 turning over operations, the successful rate of one-time posture change reached 99.9% (1 319/1 320), and no adverse event occurred. Within 2 days of admission, the lowest levels of PaO₂ and PaCO₂ of the patients were (100±19) and (42±4) mmHg, respectively, and the number of patients with mild, moderate, and severe ARDS were 10, 2, and 3, respectively, and none of the patients had oxygenation index>300 mmHg. On the 30^th day of admission, the lowest levels of PaO₂ and PaCO₂ of the patients were (135±28) and (37±8) mmHg, respectively, 3 patients developed moderate ARDS, 1 patient developed severe ARDS, and 11 patients had oxygenation index>300 mmHg. Conclusions: The introduction of feedforward control theory in the treatment of rollover bed of mass patients with burn-explosion combined injury can ensure safe and successful completion of turning over with the rollover bed, promote the repair of burn wound, and improve respiratory function, and therefore improve the treatment quality of patients.
Blood Gas Analysis ; Burns/therapy* ; Explosions ; Female ; Humans ; Male ; Respiratory Distress Syndrome ; Retrospective Studies