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1.
Article in Chinese | WPRIM | ID: wpr-774225

ABSTRACT

Marine-derived biopolymers are excellent raw materials for biomedical products due to their abundant resources, good biocompatibility, low cost and other unique functions. Marine-derived biomaterials become a major branch of biomedical industry and possess promising development prospects since the industry is in line with the trend of "green industry and low-carbon economy". Chitosan and alginates are the most commonly commercialized marine-derived biomaterials and have exhibited great potential in biomedical applications such as wound dressing, dental materials, antibacterial treatment, drug delivery and tissue engineering. This review focuses on the properties and applications of chitosan and alginates in biomedicine.

2.
Article in English | WPRIM | ID: wpr-713807

ABSTRACT

Fast progresses in stem cell-based tooth tissue engineering have been achieved in recent years in several animal models including the mouse, rat, dog, and pig. Moreover, various postnatal mesenchymal stem cells of dental origin have been isolated and shown capable of differentiating into odontoblasts and generating dentin. Meanwhile, human keratinocyte stem/progenitor cells, gingival epithelial cells, and even iPSC-derived epithelium have been demonstrated to be able to differentiate into functional ameloblasts. Translational medicine studies in the nonhuman primate are irreplaceable steps towards clinical application of stem cell-based tissue engineering therapy. In the present study, we first examined the epithelial stem cell markers in the rhesus skin using immunostaining. Keratinocyte stem cells were then isolated from rhesus epidermis, cultured in vitro, and characterized by epithelial stem cell markers. Epithelial sheets of these cultured keratinocytes, which were recombined with E13.5 mouse dental mesenchyme that possesses odontogenic potential in the presence of exogenous FGF8, were induced to differentiate into enamel-secreting ameloblasts. Our results demonstrate that in the presence of appropriate odontogenic signals, rhesus keratinocytes can be induced to gain odontogenic competence and are capable of participating in odontogenesis, indicating that rhesus keratinocytes are an ideal epithelial cell source for further translational medicine study of tooth tissue engineering in nonhuman primates.


Subject(s)
Ameloblasts , Animals , Dentin , Dogs , Epidermis , Epithelial Cells , Epithelium , Humans , In Vitro Techniques , Keratinocytes , Macaca mulatta , Mental Competency , Mesenchymal Stem Cells , Mesoderm , Mice , Models, Animal , Odontoblasts , Odontogenesis , Primates , Rats , Skin , Stem Cells , Tissue Engineering , Tooth , Translational Research, Biomedical
3.
Chinese Journal of Neonatology ; (6): 411-414, 2017.
Article in Chinese | WPRIM | ID: wpr-667041

ABSTRACT

Objective To study the perinatal outcomes of monochorionic diamnionic ( MCDA ) twins.Method A retrospective study had been conducted to analyze the outcomes of MCDA twins delivered in Hospital from Jan 2011 to Dec 2012.According to whether complicated with twin to twin transfusion syndrome ( TTTS, n=14 ) and/or selective intrauterine growth restriction ( sIUGR, n=41 ) , the infants enrolled in the study were assigned into complicated group (n=55) and uncomplicated group (n=90).The infants with sIUGR were further subdivided into three groups .The outcomes of the neonates were compared between the groups.Result A total of 145 pairs of MCDA twins were delivered , 285 neonates (12 of them died after birth ) and 5 cases of stillbirth. The gestational age at delivery in complicated group were significantly lower than those in uncomplicated group (33.8 ±2.8weeks vs.35.5 ±1.6weeks, P<0.001);The birth weight in complicated group ( the birth weight of the bigger baby was 2072 ±460 g vs.2520 ± 383 g, the smaller one 1620 ±477 g vs.2320 ±373 g ) were significantly lighter than those in uncomplicated group;The incidence of fetal death in complicated MCDA twin pregnancies (7.3% vs.0) was significantly higher than controls .Neonatal outcomes of fetuses complicated with sIUGRⅠ ( n=23 ) were similar to controls.Neonates complicated with TTTS, sIUGRⅡ(n =6) or sIUGRⅢ (n =12) had significantly increased incidence of respiratory distress syndrome , asphyxia, cardiac disorders, retinopathy of prematurity and neonatal death compared with controls .Conclusion Neonates of MCDA with TTTS or sIUGR had more complications compared with uncomplicated MCDA twins .The fetuses with abnormal umbilical artery Doppler blood flow are more vulnerable to stillbirth , neonatal death and other serious adverse outcomes .

4.
Article in Chinese | WPRIM | ID: wpr-808754

ABSTRACT

Objective@#The burden of chronic disease has been continuously increasing in China since the early 1980s. Besides the worsening of risk factors, the change in diagnostic criteria is very likely an important explanation for the increase in the prevalence of hypertension, hyperlipidemia and diabetes mellitus, three commonest, major chronic conditions that can lead to major vascular events and deaths. This study aims to estimate the contribution of changes in diagnostic criteria to the increase in the prevalence of the three conditions in China.@*Methods@#The data from two representative nation-wide surveys in China in 2002 and 2009, with 145 254 and 8 813 adults included respectively, were used to estimate the prevalence rate of the three conditions and the proportion attributable to the change in diagnostic criteria around year 2000. The new and old cutoff values for hypertension, hyperlipidemia, and hyperglycemia were 140/90 and 160/95 mmHg (1 mmHg=0.133 kPa), 5.7 and 6.2 mmol/L, and 7.0 and 7.8 mmol/L, respectively. The prevalence was standardized according to the distribution of age, sex and rural-urban residence of the 2000 national census of the country so as to compare between the old and new diagnostic criteria and project the situation for the entire country.@*Results@#The standardized prevalence of hypertension, hyperlipidemia, and diabetes mellitus for the entire Chinese adult population in 2002 was 8.21%, 1.71% and 1.43% according to the immediate previous diagnostic criteria, and 19.18%, 3.53% and 2.66% according to the new criteria. In 2009, the prevalence was 11.89%, 9.34% and 4.29% according to the old criteria, and 24.78%, 18.36% and 6.55% according to the new criteria. The total cumulative prevalence of the three conditions was increased by 124% in 2002 and 95% in 2009 as a result of change in diagnostic criteria. Put it differently, the change in diagnostic criteria increased the number of the three conditions from 2002 to 2009 by approximately 359 million and could increase the annual drug costs by some 271 billion RMB if all the conditions are treated. The drug costs alone of treating all the three conditions could consume 56% of the total health budget of the Government in 2010.@*Conclusion@#About half of the number of the three conditions is a result of the change in diagnostic criteria. These criteria were adopted from western populations, which are designed to meet the population need and suit healthcare resources available in these countries. It is important for China to consider the resources available and needs and values of the population in addition to the benefits, harms and costs of treatment in determining the cutoff values for defining these conditions for drug interventions.

5.
Article in Chinese | WPRIM | ID: wpr-480467

ABSTRACT

Objective To explore the change in anatomical volume during intensity?modulated radiotherapy (IMRT) for different stages of nasopharyngeal carcinoma (NPC) and its influence on dose distribution, and to assess the necessity to modify the IMRT plan. Methods Twenty?four patients with newly diagnosed NPC who received IMRT and chemotherapy were enrolled in the study, and were divided into early?intermediate group ( 12 cases ) and locally advanced group ( 12 cases ) according to the 2008 staging system for NPC. Each patient had a repeated CT scan at week 5 of radiotherapy, and target volume and organs at risk ( OAR) were contoured. The dose distribution of the original plan shown on CT was calculated. Changes in target volume, OAR anatomical volume, and dose distribution were analyzed, and paired t?test and Spearman correlation analysis were performed. Results In the early?intermediate group, gross target volume of neck positive lymph nodes (GTVnd) was reduced during radiotherapy (P=0. 059), and gross target volume of nasopharynx ( GTVnx ) , high?risk clinical target volume ( CTV1 ) , and parotid volume were reduced significantly during radiotherapy ( P= 0. 001, 0. 012, 0. 002, and 0. 000, respectively) . In locally advanced group, GTVnx , GTVnd , CTV1 , and parotid volume were significantly reduced during IMRT (P=0. 000, 0. 000, 0. 003, 0. 003, and 0. 000, respectively). Compared with the values before radiotherapy, the parotid dose increased significantly in the two groups during IMRT ( P=0. 044, 0. 026, 0. 033, and 0. 026, respectively;P=0. 024, 0. 016, 0. 030, and 0. 015, respectively) , and the increase in GTVnd dose was observed in the locally advanced group ( P= 0. 029 and 0. 049 ) . Conclusions It is recommended to perform another CT scan for patients with locally advanced NPC at week 5 of radiotherapy and formulate a new IMRT plan to maintain target volume dose and guarantee a safe parotid dose.

6.
Article in Chinese | WPRIM | ID: wpr-453635

ABSTRACT

Objective To investigate the hemodynamic changes and their association with the expression of β 1 and β 2 adrenoceptors after hypoxia-reoxygenation injury in a neonatal swine model of asphyxia.Methods One to four day-old piglets were randomly assigned to control group (n=6),acute hypoxia group (n=8) and subacute hypoxia group (n=8).The piglets in the control group were observed for 50 h under normoxic mechanical ventilation; while the acute and subacute hypoxia groups were subject to two hours of hypoxic injury induced by ventilation with 0.10-0.15 oxygen followed by 4 or 48 h of observation under normoxic mechanical ventilation,respectively.Blood gases were analyzed and the mean arterial blood pressure,heart rate,and cardiac output were recorded at different time points during the experiment.Tissues from the left ventricle were also harvested to assay lactate,glutathione and β adrenoceptors at the end of the experiment.Analysis of variance,the Tukey test and Pearson correlation analysis were used for statistical analysis of the data.Results Two hours after hypoxia,pH,HCO3-and partial pressure of oxygens (PO2) in the acute hypoxia group and subacute hypoxia group were lower than in the control group,however,pH and HCO3-in animals in the subacute hypoxia group recovered to 7.38 ± 0.05 and (23.04± 2.40)mmol/L,respectively,after reoxygenation,which was similar to those in the control group,and higher than in the acute hypoxia group [7.25±0.07 and (16.88±2.40) mmol/L,respectively,q=6.76 and 7.81,both P<0.01].Mean arterial pressure,cardiac output and stroke volume in the acute group and subacute group were lower than those in the control animals following two hours of hypoxic injury (all P<0.01).After reoxygenation,the mean arterial pressure in the acute hypoxia group and subacute group recovered to (42.17±6.14) and (43.19± 5.55) mmHg (1 mmHg=0.133 kPa),cardiac output recovered to (150.04± 56.17) and (169.75 ± 37.85) dl/min,respectively,and there were no differences compared with the control group (all P>0.05).Expressions of β 1 and β 2 adrenoceptors in the left ventricle in the subacute hypoxia group (1.51 ±0.51 and 2.14±0.66,respectively),were higher than those in the control group (0.56±0.24 and 0.38±0.21,q=7.02 and 10.97,both P<0.01) and the acute hypoxia group (0.65±0.20 and 0.45±0.11,q=6.86 and 11.38,both P<0.01).The lactate level in the acute hypoxia group and subacute hypoxia group was higher than that in the control group [(6.95±0.32) and (6.92±0.40) vs (5.03±0.19) μ mol/mg protein,respectively,q=15.43 and 15.19,both P<0.01].The level of glutathione in the subacute hypoxia group was lower than the control group and acute hypoxia group [(352.00± 16.51) vs (438.35±33.66) and (464.66±52.65) nmol/mg protein,respectively,q=6.00 and 8.46,both P<0.01).In the subacute hypoxia group,the expressions of β 1 and β 2 adrenoceptors were negatively correlated with the changes in cardiac output (r=-0.60 and-0.59,respectively,both P<0.05).Conclusions Severe metabolic acidosis and cardiac dysfunction resulting from perinatal asphyxia may recover after reoxygenation,which may be associated with the enhanced expression of β adrenoceptors in the left ventricle during the subacute phase.

7.
Article in Chinese | WPRIM | ID: wpr-452845

ABSTRACT

To assess the effects of resuscitation with oxygen or room air on the cardiac circulation and the activity of superoxide dismutase (SOD) in a hypoxic newborn piglet model. Methods Newborn piglets(1.6-2.5 kg) were randomly assigned into three groups:control group (n=8) with no hypoxic insult;room air group (n=12) resuscitated with room air for 240 min after 120 min hypoxia;and oxygen group (n=12) resuscitated with 100% oxygen for 30 min followed by 210 min with room air after 120 min hypoxia. Blood gas analysis, blood pressure and hemodynamic parameters were recorded at 0, 10, 30, 60, 120, 180 and 240 min of resuscitation. The activity of superoxide dismutase (SOD) in the left ventricle was measured at 240 min of resuscitation using enzyme method . One-way analysis of variance, two-way analysis of variance measured repeatedly and Student-Newman-Keuls test were applied as statistical methods. Results Severe metabolic acidosis, hypotension and hypoxemia were caused by hypoxia.(1)Arterial oxygen partial pressure(PaO2):At 10 min of resuscitation, PaO2 of control group, room air group and oxygen group was (67±4), (78±12) and (409±42)mmHg(1 mmHg=0.133 kPa) (F=580.19, P0.05). (3)Arterial oxygen content (CaO2):At 10 min of resuscitation, CaO2 of control group, room air group and oxygen group was(87.0±16.1), (76.9±13.2) and (102.2±15.9) ml O2/dl (F=8.64, P0.05). (4)Oxygen delivery (DO2): At 10, 30, 60, 120, 180 and 240 min of resuscitation, there were no statistical significance among DO2 of control group, room air group and oxygen group [10 min:(16.5±3.3), (15.7±9.9) and (16.9±4.2)L O2/(kg·min), F=0.10;30 min:(16.2±4.1), (15.1±5.5) and (14.5±3.3) L O2/(kg·min), F=0.38;60 min:(16.1±4.2), (14.9±4.0)and(13.3±3.8)L O2/(kg·min), F=1.28;120 min:(15.5±3.7),(15.6±6.1)and(13.4± 4.6) L O2/(kg·min), F=0.66;180 min:(15.4±3.1), (15.3±9.3) and (11.9±5.0) L O2/(kg·min), F=0.97;240 min:(14.7±3.4), (13.4±6.7) and (9.3±5.2) L O2/(kg·min), F=2.84;all P>0.05]. (5) SOD activity in the left ventricle:At 240 min of resuscitation, SOD activity of control group (n=6), room air group (n=8) and oxygen group (n=8) was (289±107), (210±75) and (142±61)U/mg protein, F=5.75, P0.05). Conclusions Despite higher oxygen content in the blood, resuscitation with oxygen is not beneficial to recovery from metabolic acidosis in newborn hypoxic piglets. Oxygen supplementation does not increase oxygen delivery but reduces SV compared to resuscitation with room air. Resuscitation with oxygen may impair the oxidative stress defense.

8.
Article in Chinese | WPRIM | ID: wpr-438930

ABSTRACT

BACKGROUND:The tumor tissue engineering can build an integrated culture model to ful y simulate the in vivo microenvironment of tumor growth, which can be used to study tumor developmental dynamics and related treatment strategies. OBJECTIVE:To review the three-dimensional culture of tumor cells using tumor engineering technology. METHODS:PubMed database was retrieved for articles related to tumor engineering, three-dimensional culture of tumor cells, biological scaffold materials and tumor microenvironment published from January 1992 to March 2013. RESULTS AND CONCLUSION:Three-dimensional culture, because of its reproducible tissue and cellgrowth in vivo, has become an important platform for study of tumor resistance, invasiveness and tumor microenvironment. The three-dimensional culture has showed a trend to gradual y replace the flat culture technique in many fields, and provides a research platform which is very close to in vivo environment. In recent years, with the development of tumor engineering, a variety of new polymer materials have been used in the three-dimensional culture of tumor cells. Three-dimensional culture technology is becoming a hotspot in the field of tumor biology, in which, using a variety of methods and materials, the cells show a growth in the spatial manner to form a biological support or matrix similar to in vivo growth environment. Biomaterials have become the soil on which seed cells can grow wel , and plays an alternative to the extracellular matrix or the matrix of tissues and organs in the tumor engineering. Therefore, the three-dimensional cellculture has been widely used in cancer research, which has become a powerful tool to tumor drug resistance, angiogenesis, cel-cellinteraction, signal transduction, stem cells and other research.

9.
Article in Chinese | WPRIM | ID: wpr-422637

ABSTRACT

Objective To observe early histopathological changes in explosive wounds at canine limbs after seawater inmersion.Methods Forty adult dogs,weighing 10 to 15 kg each,were assigned into 2 equal groups.The left hind limb of each dog in both groups was injured by a man-made explosion.The explosive wound was first washed by normal sodium.The 20 injured limbs in the experimental group (EG)were immersed in seawater for one hour while those in the control group (CG) were only exposed naturally for one hour without seawater immersion.All the wounds were covered with sterile dressing without suture.The pus and soft tissue at the wound were taken for pathological examination,bacterial culture and drug sensitivity test on day 3.The time of wound healing was recorded.Tissue sections were taken from the wounds for pathological examination at 4 and 8 weeks.Results Fifteen wounds (75%) were infected in the EG,significantly more than the 8 wounds infected (40%) in the CG( P < 0.05).The wounds healed in a mean time of 38.4 days in the EG,significantly longer than the mean time for wound healing (23.1 days) in the CG ( P < 0.05).In the EG,Vibrio infection caused more serious tissue necrosis and inflammatory reaction than Bacillus and coccus did.At 4 and 8 weeks,tissue necrosis and inflammatory reaction in the EG were worse than those in the CG.Conclusion Seawater immersion can lead to increased infective tissue necrosis and inflammatory reaction in an explosive wound,as well as longer time for wound healing.

10.
Saudi Medical Journal. 2011; 32 (7): 701-707
in English | IMEMR | ID: emr-129975

ABSTRACT

To investigate the effect of Alismatis rhizome [AR] extract on lipid profile in mice fed high-fat diet. The study was performed in Key Laboratory of Chinese Medicine Resource and Compound Prescription [Hubei University of Chinese Medicine], Ministry of Education, Wuhan, China, between December 2009 and June 2010. Forty male Kunming mice [8-week-old] were randomly divided into 4 groups and were treated for 4 weeks: Group 1: normal control, Group 2: high-fat control, Group 3: positive control and Group 4: AR 2.26g/kg. The hypolipidemic effects of AR were evaluated by serum lipids, liver lipids, and reverse transcriptase polymerase chain reaction. Serum aminotransferases and histopathological changes were also measured. Alismatis rhizome treatment resulted in an obvious decrease in serum and liver cholesterol, triglyceride along with elevated serum high-density lipoprotein cholesterol in hyperlipidemic mice. The histopathological results showed that adipose vacuoles in AR treated mice liver were almost identical to those of normal control mice. Serum alanine transaminase, aspartate aminotransferase and the relative liver weight in AR treated mice were decreased significantly. Alismatis rhizome substantially decreased the mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase [Hmgcr], while the expressions of sterol regulatory element binding factor 2 [Srebf2] and cholesterol 7alpha-hydroxylase [Cyp7a1] were marginally affected. These results confirmed the efficacy of AR in the treatment of hyperlipidemia. Alismatis rhizome may act by decreasing the liver synthesis of cholesterol, rather than by increasing the cholesterol catabolism


Subject(s)
Animals , Male , Hyperlipidemias/drug therapy , Diet, High-Fat , Plant Extracts , Rhizome , Hyperlipidemias/blood , Triglycerides/blood , Cholesterol/blood , Mice
11.
Chinese Journal of Biotechnology ; (12): 1690-1695, 2010.
Article in Chinese | WPRIM | ID: wpr-351547

ABSTRACT

Generation of bio-engineered teeth by using stem cells will be a major approach for bioengineered implantation. Previous studies have demonstrated that dissociated tooth germ cells are capable of generating a tooth after reaggregation in vitro. However, the cellular and molecular mechanisms underlying this tooth regeneration are not clear. In this study, we dispersed E13.5 molar germ into single cells, immediately reaggregated them into cell pellet, then grafted the reaggregates under mouse kidney capsule for various times of culture. We investigated the morphogenesis and the expression of several developmental genes in dental epithelial cells in reaggregates of tooth germ cells. We found that dissociated tooth germ cells, after reaggregation, recapitulated normal tooth developmental process. In addition, dissociated dental epithelial cells retained the expression of Fgf8, Noggin, and Shh during reaggregation and tooth regeneration processes. Our results demonstrated that, despite of under dissociated status, dental epithelial cells maintained their odontogenic fate after re-aggregation with dental mesenchymal cells. These results provided important information for future in vitro generation of bio-engineered teeth from stem cells.


Subject(s)
Animals , Cell Culture Techniques , Methods , Cell Differentiation , Embryo, Mammalian , Epithelial Cells , Cell Biology , Metabolism , Female , Gene Expression Regulation, Developmental , Genetics , Male , Mice , Odontogenesis , Genetics , Tooth Germ , Cell Biology , Physiology
12.
Article in Chinese | WPRIM | ID: wpr-525579

ABSTRACT

Objective To investigate the clinical manifesfations and diagnostic and therapeutic features of cholangiocarcinoma associated with hepatolithiasis.Methods The clinical data, the diagnotic and therapeutic featares of 54 cases of cholangiocacinoma associated with hepatolithiasis were retrospectively analyzed.Results The occurrence rate of hepatolithiasis concomitant with hepatocholangiocarcinoma was 11.8%.Due to a lack of specific clinical manifestations, the preoperative diagnosis of this condition was difficult. In this series, the (correct) diagnotic rate of hepatocholangiocarcinoma before operation was only 11.1%. The radical resection rate was 51.8%. Radical resection of the tumor had a better prognosis than that of non-resection of tumor.(Conclusions) Patients with long-term recurrent hepatolithiasis tended to have associated cholangiocarcinoma. Early diagnosis of the disease was difficult, and the treatment results and prognosis were poor. Therefore, (patients) with hepatolithiasis, espesially those with recurrent attacks, should undergo operation early. In cases diagnosed as hepatic cholangioearcinoma at operation, a radical resection should be performed, if possible, and a favorable outcome may be attained.

13.
Article in Chinese | WPRIM | ID: wpr-579289

ABSTRACT

Objective In order to protect the natural resources of Swertia bimaculata which has been destroyed seriously,the method of artificial propagation by way of tissue culture have been systematically studied.Methods The stems,leaves,and stems with buds which were from the seedlings germinated from the seeds on the initial medium were taken as explants.These explants were cultured on MS culture media by adding different portions of hormones at various cultural conditions.Results The stems were the best material in speeding propagation among the three explants.The proper initial medium for the stems was MS+ BA 0.5 mg/L+saccharose 3.0%,the optimum medium for proliferation was MS+BA 0.5 mg/L+IBA 0.1 mg/L+saccharose 3.0%,and the best medium for rooting was 1/2MS+NAA 0.5 mg/L+saccharose 1.5%.Conclusion Tissue culture of S.bimaculata could make its propagation rapid,its resources preserved,and its utilization last.

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