BACKGROUND:Matrigel is the best material for the culture of tumor organoids,but matrigel alone is not enough to simulate the mechanical environment of tumor growth in vitro.Although the introduction of sodium alginate material can improve the stiffness of the hydrogel based on matrigel,its mechanical properties of hydrogel are difficult to maintain stability in long-term culture.OBJECTIVE:To introduce a small amount of calcium ions into the medium of breast cancer organoids and to observe its maintenance effect on the long-term mechanical properties of the matrigel-sodium alginate hydrogel.METHODS:(1)Sodium alginate composite hydrogels with low,medium,and high stiffness were prepared by introducing different mass concentrations(0,2.5,and 5 mg/mL)of sodium alginate into the constant mass concentration(5 mg/mL)of matrigel.The mechanical properties of hydrogels were measured regularly by rheometer.(2)Human triple negative breast cancer cells MDA-MB-231 were resuspended in hydrogel pre-gels with different stiffness.After gelling,breast cancer organoid factor medium containing(or without)calcium ions was added for breast cancer organoid culture.At a set time point,rheometer was used to regularly measure the effect of calcium ion introduction on the mechanical properties of hydrogel.The morphologic changes of breast cancer organoids were observed under optical microscope.Rate of breast cancer organoids forming into pellets was calculated on day 13.After 7 days of breast cancer organoid culture,different concentrations of the chemotherapy drug docetaxel(0.1,1,10,and 100 nmol/L)were added for intervention for 6 days.Cell viability was detected and the semi-inhibitory concentration of docetaxel,IC50,was calculated.RESULTS AND CONCLUSION:(1)The introduction of sodium alginate effectively improved the mechanical strength of the composite hydrogel.(2)With the extension of breast cancer organoid culture time,the mechanical strength of hydrogels decreased.On day 13 of culture,the mechanical properties of medium and high stiffness hydrogels in the culture environment containing calcium ions were significantly higher than those in the culture environment without calcium ions(P<0.05).There was no significant change in the mechanical properties of low stiffness hydrogels in the two cultures(P>0.05).In long-term culture(13 days),breast cancer organoids changed from round to spindle shape with the decrease of hydrogel mechanical properties in the medium and high stiffness hydrogel groups.After the introduction of calcium ions,the morphology of breast cancer organoids did not change with the extension of culture time in the two groups.The introduction of calcium ions in the culture environment had no effect on the pellet formation rate of breast cancer organoids in the low stiffness hydrogel group,but could improve the pellet formation rate of breast cancer organoids in the medium and high stiffness hydrogel groups.(3)In the culture environment without calcium ions,the cell viability of breast cancer organoids decreased with the increase of docetaxel concentration,and there was no significant difference in IC50 among the three hydrogel groups(P>0.05).In the culture environment containing calcium ions,the cell viability of breast cancer organoids decreased with the increase of docetaxel concentration.The cell viability of breast cancer organoids in the medium and high stiffness hydrogel groups was stronger than that in the low stiffness hydrogel group,and the IC50 was higher than that in the low stiffness hydrogel group(P<0.05).(4)The results showed that the mechanical properties of the matrigel-sodium alginate hydrogel could be maintained by introducing calcium ions into the breast cancer organoid culture system.

BACKGROUND:Matrigel is the best material for the culture of tumor organoids,but matrigel alone is not enough to simulate the mechanical environment of tumor growth in vitro.Although the introduction of sodium alginate material can improve the stiffness of the hydrogel based on matrigel,its mechanical properties of hydrogel are difficult to maintain stability in long-term culture.OBJECTIVE:To introduce a small amount of calcium ions into the medium of breast cancer organoids and to observe its maintenance effect on the long-term mechanical properties of the matrigel-sodium alginate hydrogel.METHODS:(1)Sodium alginate composite hydrogels with low,medium,and high stiffness were prepared by introducing different mass concentrations(0,2.5,and 5 mg/mL)of sodium alginate into the constant mass concentration(5 mg/mL)of matrigel.The mechanical properties of hydrogels were measured regularly by rheometer.(2)Human triple negative breast cancer cells MDA-MB-231 were resuspended in hydrogel pre-gels with different stiffness.After gelling,breast cancer organoid factor medium containing(or without)calcium ions was added for breast cancer organoid culture.At a set time point,rheometer was used to regularly measure the effect of calcium ion introduction on the mechanical properties of hydrogel.The morphologic changes of breast cancer organoids were observed under optical microscope.Rate of breast cancer organoids forming into pellets was calculated on day 13.After 7 days of breast cancer organoid culture,different concentrations of the chemotherapy drug docetaxel(0.1,1,10,and 100 nmol/L)were added for intervention for 6 days.Cell viability was detected and the semi-inhibitory concentration of docetaxel,IC50,was calculated.RESULTS AND CONCLUSION:(1)The introduction of sodium alginate effectively improved the mechanical strength of the composite hydrogel.(2)With the extension of breast cancer organoid culture time,the mechanical strength of hydrogels decreased.On day 13 of culture,the mechanical properties of medium and high stiffness hydrogels in the culture environment containing calcium ions were significantly higher than those in the culture environment without calcium ions(P<0.05).There was no significant change in the mechanical properties of low stiffness hydrogels in the two cultures(P>0.05).In long-term culture(13 days),breast cancer organoids changed from round to spindle shape with the decrease of hydrogel mechanical properties in the medium and high stiffness hydrogel groups.After the introduction of calcium ions,the morphology of breast cancer organoids did not change with the extension of culture time in the two groups.The introduction of calcium ions in the culture environment had no effect on the pellet formation rate of breast cancer organoids in the low stiffness hydrogel group,but could improve the pellet formation rate of breast cancer organoids in the medium and high stiffness hydrogel groups.(3)In the culture environment without calcium ions,the cell viability of breast cancer organoids decreased with the increase of docetaxel concentration,and there was no significant difference in IC50 among the three hydrogel groups(P>0.05).In the culture environment containing calcium ions,the cell viability of breast cancer organoids decreased with the increase of docetaxel concentration.The cell viability of breast cancer organoids in the medium and high stiffness hydrogel groups was stronger than that in the low stiffness hydrogel group,and the IC50 was higher than that in the low stiffness hydrogel group(P<0.05).(4)The results showed that the mechanical properties of the matrigel-sodium alginate hydrogel could be maintained by introducing calcium ions into the breast cancer organoid culture system.

BACKGROUND:Sodium alginate,a natural polysaccharide,has become one of the ideal materials for preparing injectable hydrogels because it is an abundant and cheap resource,and has good biocompatibility and biodegradability.It has been widely used in the production of injectable hydrogels. OBJECTIVE:To review the properties of sodium alginate,the preparation of injectable sodium alginate hydrogel,and its application progress in tissue engineering. METHODS:Web of Science,PubMed,and CNKI were searched by computer.Chinese search terms were"sodium alginate;hydrogel;injectable",and English search terms were"alginate;hydrogel;inject".The time range of searching literature was mainly from June 2017 to June 2022. RESULTS AND CONCLUSION:Alginic acid comes from a wide range of sources,and there are many modifiable groups in its molecular structure,so many injectable hydrogels with excellent properties can be produced by various chemical crosslinking or physical crosslinking methods.Introducing other bioactive molecules or drugs into sodium alginate gel can adjust its properties and broaden its application fields.In addition,injectable sodium alginate hydrogels have great application prospects in biomedicine because of their good biocompatibility,biodegradability and other physical and chemical properties.Sodium alginate hydrogels are evenly mixed with various drugs,cells,factors or other biological molecules in vitro,and can form gels in the human body,which plays a pivotal role in gene carrier,cell scaffold and wound repair.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.

BACKGROUND:The objective of this retrospective hospital-based study was to describe the epidemiological features of traumatic spinal cord injury(TSCI)in the intensive care unit(ICU)and assess the incidence and possible risk factors for venous thromboembolism(VTE)following TSCI. METHODS:We retrospectively reviewed the medical records of 370 patients with TSCI who were admitted between January 2018 and March 2023.The following parameters were collected:age,sex,body mass index,occupation,underlying diseases,smoking history,education level,etiology of injury,injury segments,American Spinal Injury Association(ASIA)Impairment Scale score,severity of injury,injury severity score(ISS),VTE risk score(Caprini score),treatment,VTE prophylaxis,ICU length of stay,length of hospital stay,concomitant injuries,and complications.Descriptive statistics were used to summarize the demographic and clinical characteristics of the study participants.Logistic regression analysis was used to determine the risk factors for VTE. RESULTS:The mean age of patients with TSCI was 55.5±13.4 years,with a male-to-female ratio of 6.5:1.The leading cause of TSCI was falls from height(46.5%),followed by traffic accidents(36.5%).The cervical spinal cord was the most affected segment,followed by the thoracolumbar region.Among all the patients,362(97.8%)had concomitant injuries.Complications were observed in 255 patients(68.9%)during hospitalization.The incidence rate of VTE was 25.1%.Logistic regression analysis revealed that age(OR=1.721,95%CI:1.207-2.454,P=0.003),mechanical ventilation(OR=3.427,95%CI:1.873-6.271,P<0.001),and non-use of chemical prophylaxis(OR=2.986,95%CI:1.749-5.099,P<0.001)were risk factors for VTE. CONCLUSION:Falls from height and traffic accidents were the main causes of TSCIs in the ICU,especially for male patients with cervical spinal cord injuries.VTE is a frequent complication in patients with TSCI in the ICU.Age,mechanical ventilation,and non-use of chemical prophylaxis were found to be independent risk factors for VTE following TSCI.