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1.
J Med Virol ; 96(3): e29481, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38425184

RESUMO

Hepatitis C remains a global health problem, especially in poverty-stricken areas. A rapid and sensitive point-of-care (POC) diagnostic tool is critical for the early detection and timely treatment of hepatitis C virus (HCV) infection. Here, for the first time, we reported a novel molecular diagnostic assay, termed reverse transcription multiple cross displacement amplification integrated with a gold-nanoparticle-based lateral flow biosensor (RT-MCDA-AuNPs-LFB), which was developed for rapid, sensitive, specific, and visual identification of HCV. HCV-RT-MCDA induced rapid isothermal amplification through a specific primer set targeting the 5'untranslated region gene from the major HCV genotypes 1b, 2a, 3b, 6a, and 3a that are prevalent in China. The optimal reaction temperature and time for RT-MCDA-AuNPs-LFB were 68°C and 25 min, respectively. The limit of detection of the assay was 10 copies per test, and the specificity was 100% for the experimental strains. The whole detection procedure, including crude nucleic acid isolation (~5 min), RT-MCDA (68°C, 25 min), and visual AuNPs-LFB result confirmation (less than 2 min), was performed within 35 min. The preliminary results indicated that the HCV-RT-MCDA-AuNPs-LFB assay could be a valuable tool for sensitive, specific, visual, cost-saving, and rapid detection of HCV and has potential as a POC diagnostic platform for field screening and early clinical detection of HCV infection.


Assuntos
Técnicas Biossensoriais , Hepatite C , Nanopartículas Metálicas , Humanos , Hepacivirus/genética , Sensibilidade e Especificidade , Técnicas de Amplificação de Ácido Nucleico/métodos , Ouro , Hepatite C/diagnóstico , Técnicas Biossensoriais/métodos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38492560

RESUMO

OBJECTIVES: The primary objective of this research was to evaluate the safety and feasibility of an innovative double-branched stent graft system employing four-stage deployment technology for aortic arch repair in porcine models. METHODS: The double-branched stent graft system consisted of a proximal polyester artificial blood vessel, the main and double-branched stent grafts and a delivery system. We utilized 12 healthy pigs as experimental animals (6 per group). Postimplantation, samples were collected at 90 and 180 days after the operations. Preoperative and postoperative imaging and intraoperative arterial blood gas analyses were performed. After the pigs were euthanized, the implanted product, surrounding tissue and major organs were collected for pathological analysis. RESULTS: The technical success rate of the stent graft implants was 100% (12/12). All animals survived to the experimental end point. Perioperative assessments showed intact stent grafts, and imaging features at the end of the follow-up period revealed neither endoleak nor device migration. No major adverse cardiovascular events were observed during the postoperative follow-up period. Pathological examinations confirmed the satisfactory biocompatibility of the stent graft. CONCLUSIONS: This innovative double-branched stent graft system with four-stage deployment technology was affirmed as a safe and feasible option for aortic arch repair in accordance with our preclinical evaluation with porcine models.

3.
BMC Microbiol ; 24(1): 68, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38413863

RESUMO

OBJECTIVES: In the current study, for the first time, we reported a novel HCV molecular diagnostic approach termed reverse transcription loop-mediated isothermal amplification integrated with a gold nanoparticles-based lateral flow biosensor (RT-LAMP-AuNPs-LFB), which we developed for rapid, sensitive, specific, simple, and visual identification of HCV. METHODS: A set of LAMP primer was designed according to 5'untranslated region (5'UTR) gene from the major HCV genotypes 1b, 2a, 3b, 6a, and 3a, which are prevalent in China. The HCV-RT-LAMP-AuNPs-LFB assay conditions, including HCV-RT-LAMP reaction temperature and time were optimized. The sensitivity, specificity, and selectivity of our assay were evaluated in the current study. The feasibility of HCV-RT-LAMP-AuNPs-LFB was confirmed through clinical serum samples from patients with suspected HCV infections. RESULTS: An unique set of HCV-RT-LAMP primers were successfully designed targeting on the 5'UTR gene. The optimal detection process, including crude nucleic acid extraction (approximately 5 min), RT-LAMP reaction (67℃, 30 min), and visual interpretation of AuNPs-LFB results (~ 2 min), could be performed within 40 min without specific instruments. The limit of detection was determined to be 20 copies per test. The HCV-RT-LAMP-AuNPs-LFB assay exhibited high specificity and anti-interference. CONCLUSIONS: These preliminary results confirmed that the HCV-RT-LAMP-AuNPs-LFB assay is a sensitive, specific, rapid, visual, and cost-saving assay for identification of HCV. This diagnostic approach has great potential value for point-of-care (POC) diagnostic of HCV, especially in resource-challenged regions.


Assuntos
Técnicas Biossensoriais , Hepatite C , Nanopartículas Metálicas , Humanos , Hepacivirus/genética , Ouro , Sensibilidade e Especificidade , Regiões 5' não Traduzidas , Hepatite C/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas Biossensoriais/métodos
4.
Front Cardiovasc Med ; 10: 1263897, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771668

RESUMO

Due to structural abnormalities in the leaflets, patients with bicuspid aortic valve (BAV) may develop isolated aortic valve disease, such as aortic regurgitation, aortic stenosis, or a combination of both. In addition to valvular pathology, numerous studies have indicated that approximately 40% of BAV patients exhibit aortic pathologies characterized by aortic dilatation. According to guidelines for valvular diseases, patients with BAV who require surgical aortic valve replacement (SAVR) and have a diameter of the aortic sinuses or ascending aorta ≥4.5 cm are recommended to undergo concomitant replacement of the aortic sinuses or ascending aorta. However, we encountered a case in 2020 involving a patient with severe aortic regurgitation due to BAV and an ascending aortic diameter of 4.2 cm. This patient underwent SAVR and ascending aortoplasty surgery at our center. Remarkably, three years postoperatively, the patient's aortic diameter rapidly expanded by nearly threefold, which also suggests the risk of encountering a giant aortic root aneurysm during reoperation. Unfortunately, a fatal rupture of a giant aortic root aneurysm was encountered during re-sternotomy. Fortunately, with adequate preoperative planning, we successfully managed to avert this perilous situation. The patient recovered without complications and was discharged on the 8th day. Individualized surgical plans were formulated based on a comprehensive evaluation of the perioperative conditions.

5.
Trials ; 24(1): 496, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543681

RESUMO

BACKGROUND: Total arch replacement with frozen elephant trunk has been developed with promising results for DeBakey type I aortic dissection. However, several problems, such as continuous perfusion of distal false lumen and unfavorable remodeling of distal aorta postoperatively, can seriously affect the long-term outcome. This trial aims to assess the effects of early minimally invasive endovascular repair on distal aortic remodeling and long-term clinical outcomes in patients with dominant false lumen and residual tears in the descending thoracic aorta after total arch replacement and frozen elephant trunk procedure. METHODS: This is a protocol for a two-arm, parallel, multicenter, randomized controlled trial. A total of 154 eligible patients will be recruited from four hospitals in China and randomized on a 1:1 basis either to the experiment group (endovascular repair in addition to routine antihypertensive therapy) or the control group (routine antihypertensive therapy without early surgical treatment). The primary outcome will be the five-year all-cause mortality. The secondary outcomes will include re-intervention, ischemic symptoms, organ dysfunction, and stent-related adverse events. DISCUSSION: If early minimally invasive endovascular repair could safely and effectively promote distal aortic remodeling and bring favorable long-term outcomes for patients with dominant false lumen and residual tears in the descending thoracic aorta after total arch replacement and frozen elephant trunk technique, it would improve the treatment strategy for DeBakey type I aortic dissection. TRIAL REGISTRATION: Chinese Clinical Trial Registry, CHiCTR2000030050. Registered on 11 March 2020.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Anti-Hipertensivos , Implante de Prótese Vascular/efeitos adversos , Resultado do Tratamento , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Stents , Procedimentos Endovasculares/métodos , Estudos Retrospectivos , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
6.
Physiol Meas ; 44(9)2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37625435

RESUMO

Objective. Neonatal jaundice is a common condition in the early stages of newborns, and phototherapy is a fast, safe and effective method that is used to treat it. However, recent studies have shown that phototherapy may elicit side effects in infants, such as hypothermia, hyperthermia and dehydration. To improve the quality of phototherapy and the prognosis of patients, the changes in neonatal physiological parameters during phototherapy should be monitored to give better feedback to pediatricians or the phototherapy system. However, the current standard of clinical care during neonatal phototherapy with hard-wired devices limits this realization.Approach. Here, we developed a prototype of a neonatal wearable device, which can wirelessly potentially monitor the jaundice value, transepidermal water loss, skin wettedness factor and body orientation during phototherapy, and conducted prototype validation experiments. We also set up user-friendly interfaces and an analysis system on custom software, all designed to make the future addition of data interfaces for treatment feedback functions easier.Main results. The preliminaryin vitroexperiment demonstrated the effectiveness of simultaneous monitoring of the required physiological parameters. And further suggestions and specific operations are discussed in terms of optimization of the treatment of neonatal jaundice.Significance. It is believed that the established system has the potential to provide a basis for future phototherapy nursing guidelines and physiological monitoring standards.


Assuntos
Icterícia Neonatal , Recém-Nascido , Lactente , Humanos , Retroalimentação , Icterícia Neonatal/terapia , Fototerapia , Febre , Monitorização Fisiológica
7.
Front Cardiovasc Med ; 10: 1185089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293279

RESUMO

Giant coronary artery aneurysm (CAA) is a relatively uncommon disease that is defined by a focal dilation of at least 20 mm and characterized by various clinical symptoms. However, cases presenting primarily with hemoptysis have not been reported. A man in his late 20 s suffering from persistent chest pain for over 2 months was transferred to our emergency department for intermittent hemoptysis lasting for 12 h. Bronchoscopy detected fresh blood in the left upper lobe bronchus without a definite bleeding source. Magnetic resonance imaging (MRI) demonstrated a heterogeneous mass and the high-intensity signals suggested active bleeding. coronary computed tomography (CT) angiography demonstrated a giant ruptured CAA wrapped in a large mediastinal mass Coronary angiography confirmed the CAA originating from the left anterior descending artery. The patient underwent an emergency sternotomy and an enormous hematoma arising from a ruptured CAA densely adhering to the left lung was identified. The patient recovered uneventfully and was discharged on the 7th day later. The ruptured CAA masquerading as hemoptysis highlights the indispensability of multimodality imaging for accurate diagnosis. Urgent surgical intervention is desirable in such life-threatening conditions.

8.
Front Cardiovasc Med ; 10: 1173945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234372

RESUMO

Background and aim: The evolution of the false lumen after the repair of acute aortic dissection has been linked to numerous adverse clinical outcomes, including increased late mortality and a higher risk of reoperation. Despite the widespread use of chronic anticoagulation in patients who have undergone repair for acute aortic dissection, the effects of this therapy on false lumen evolution and its subsequent consequences are yet to be fully understood. This meta-analysis aimed to investigate the impact of postoperative anticoagulation on patients with acute aortic dissection. Methods: In PubMed, Cochrane Libraries, Embase, and Web of Science, we performed a systematic review of nonrandomized studies, comparing outcomes with postoperative anticoagulation vs. non-anticoagulation on aortic dissection. We investigated the status of false lumen (FL), aorta-related death, aortic reintervention, and perioperative stroke in aortic dissection patients with anticoagulation and non-anticoagulation. Results: After screening 527 articles, seven non-randomized studies were selected, including a total of 2,122 patients with aortic dissection. Out of these patients, 496 received postoperative anticoagulation while 1,626 served as controls. Meta-analyses of 7 studies revealed significantly higher FL patency in Stanford type A aortic dissection (TAAD) postoperative anticoagulation with an OR of 1.82 (95% CI: 1.22 to 2.71; Z = 2.95; I²=0%; P = 0.93). Moreover, there was no statistically significant difference between the two groups in aorta-related death, aortic reintervention, and perioperative stroke with an OR of 1.31 (95% CI: 0.56 to 3.04; Z = 0.62; I² = 0%; P = 0.40), 0.98 (95% CI: 0.66 to 1.47; Z = 0.09; I² = 23%; P = 0.26), 1.73 (95% CI: 0.48 to 6.31; Z = 0.83; I² = 8%; P = 0.35), respectively. Conclusions: Postoperative anticoagulation was associated with higher FL patency in Stanford type A aortic dissection patients. However, there was no significant difference between the anticoagulation and non-anticoagulation groups in terms of aorta-related death, aortic reintervention, and perioperative stroke.

9.
Cardiovasc Intervent Radiol ; 46(6): 703-712, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37198293

RESUMO

PURPOSE: To report the early 2-year results and experience of a novel gutter-plugging chimney stent-graft in a single center that participated in the clinical trial of Prospective Study for Aortic Arch Therapy with stENt-graft for Chimney technology. MATERIALS AND METHODS: Patients diagnosed with aortic dissection were treated with the novel chimney stent-grafts named Longuette™ for the left subclavian artery revascularization. Primary study outcomes were the incidence of freedom from major adverse events within 30 days and success rate of the operation over 12 months. RESULTS: A total of 34 patients were enrolled between September 2019 and December 2020. The immediate technical success rate (stent-grafts successfully deployed without fast-flow type Ia or type III endoleak intraoperatively) was 100%, and there were no conversions to open repair. Type Ia and type II endoleaks were noted in three patients (8.8%) and one patient (2.9%) at discharge, respectively. One patient (2.9%) with type Ia endoleak underwent coil embolization at 12 months because of false lumen dilation, and one (2.9%) case of type Ia endoleak resolved spontaneously at 24 months. One chimney stent (2.9%) was revealed with stenosis at discharge and occluded with thrombosis at 6 months postoperatively. During the 2-year follow-up, there was no death, rupture, stroke, paraplegia, left arm ischemia, retrograde dissection, stent-graft induced new entry, or stent migration. CONCLUSION: The initial results of the Longuette™ stent-graft for revascularization of the left subclavian artery are encouraging with a high technical success rate. Further multicenter follow-up outcomes are required to assess the long-term durability. LEVEL OF EVIDENCE: Level 4, Case Series.


Assuntos
Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Endoleak/cirurgia , Implante de Prótese Vascular/métodos , Estudos Prospectivos , Resultado do Tratamento , Prótese Vascular/efeitos adversos , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Stents/efeitos adversos , Procedimentos Endovasculares/métodos , Desenho de Prótese , Estudos Retrospectivos
11.
Ann Emerg Med ; 81(1): 100-110, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36543478
12.
J Clin Transl Res ; 8(6): 516-522, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36452005

RESUMO

Background and Aim: This study aims to investigate thyroid function-associated parameters and the incidence of thyroid disorders in pregnant women, with the overarching aim to ensure that pregnant women do not develop said disorders due to aberrant iodine levels during the course of pregnancy. Methods: A total of 300 pregnant women who underwent routine check-ups at the Yongchuan Hospital Affiliated to Chongqing Medical University from January to December 2021 were enrolled. Venous blood and morning urine were collected. Serum thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were determined by chemiluminescence immunoassay. Urinary iodine concentration (UIC) was detected by arsenic cerium catalytic spectrophotometry. Thyroid disorders were extrapolated from the measured parameters. Results: The overall median UIC was 203 µg/L, which was within normal range. Subgroup analysis revealed that the median UIC in the first trimester was 187.5 µg/L, 211.8 µg/L in the second trimester, and 239.9 µg/L in the third trimester. However, based on the WHO criteria, 32%, 30%, and 18% of pregnant women were iodine deficient during their first, second, and third trimester, respectively. The proportion of women with iodine deficiency in the first and second trimesters was higher compared to the third trimester (P < 0.05). Serum FT3 and FT4 concentrations were higher in subjects in their first and second trimester versus the third trimester, while serum TSH levels were lower in subjects in their first and second trimester versus the third trimester (P < 0.05). The TSH concentration in subjects with inadequate iodine intake (UIC < 150 µg/L) was lower compared to subjects with adequate iodine intake (UIC 150 - 249 µg/L), but higher than in subjects with more than adequate intake (UIC 250 - 499 µg/L) and excess iodine intake (UIC ≥ 500 µg/L) (P < 0.05). TSH concentration and UIC were positively correlated (r = 0.1945, P = 0.0007), while no relationship was observed between UIC and FT3 and FT4 serum levels (r1 = -0.0593, P1 = 0.3053; r2 = -0.0149, P2 = 0.7968). There was no significant difference in FT3 and FT4 concentration between different UIC strata (P > 0.05). The incidence of thyroid disease during pregnancy in iodine-deficient women was greater compared to pregnant women with adequate iodine intake (P < 0.05) and higher in subjects in the more than adequate as well as excessive iodine intake cohorts (P < 0.05). Conclusion: The iodine nutritional intake by pregnant women in Yongchuan District, Chongqing, was generally sufficient to meet developmental and metabolic needs. However, about a third of women in their first and second trimester exhibited iodine deficiency. Iodine deficiency was associated with an increased incidence of thyroid diseases. Relevance for Patients: In clinical practice, the UIC of pregnant women should be measured during key stages in the pregnancy to prevent the manifestation of thyroid diseases.

13.
JAMA Cardiol ; 7(11): e223042, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36350316

RESUMO

This case report describes a diagnosis of cardiac tamponade secondary to ruptured coronary artery aneurysm in a man who presented with acute chest pain and dyspnea.


Assuntos
Aneurisma Roto , Tamponamento Cardíaco , Aneurisma Coronário , Masculino , Humanos , Tamponamento Cardíaco/etiologia , Vasos Coronários/diagnóstico por imagem , Aneurisma Coronário/diagnóstico , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Roto/complicações , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia
16.
Appl Biochem Biotechnol ; 194(5): 2236-2250, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35066748

RESUMO

[Formula: see text] plays an important role as an intracellular second messenger in the growth and development of cardiomyocytes (CMs), which can be visualized by calcium imaging and be quantified as calcium transient. Based on calcium imaging, the widely applied measurement method for cellular calcium transient requires laborious and inefficient calibration experiments, as well as affected by photobleaching. In this study, we presented a calibration-free method, based on calcium imaging, to calculate cellular calcium transient and correct photobleaching directly from the target video. We also set up image acquisition and calculation system on custom software, applied to calcium transients monitoring of neonatal rat cardiomyocytes. Results showed that the effect of the new method was similar to that of the traditional one with a Pearson correlation coefficient of 0.99 ± 0.01. Moreover, the residual sum of squares of the two methods was only 26.31 ± 26.28 when the area of the region of interest was greater than 8% of the image area. This result indicated that the new method provided a new concept of cellular [Formula: see text] concentration quantification as well as a rapid and adaptive method for monitoring cellular calcium transient.


Assuntos
Sinalização do Cálcio , Cálcio , Animais , Cálcio/metabolismo , Calibragem , Miócitos Cardíacos/metabolismo , Ratos
17.
Front Neurosci ; 16: 1065629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36711129

RESUMO

Background: Assessing hand sensation in stroke patients is necessary; however, current clinical assessments are time-consuming and inaccurate. Objective: This study aimed to explore the nature of light touch sensation and two-point discrimination (2-PD) of different hand sites in convalescent stroke patients based on somatosensory evoked potentials (SEP). Methods: Light touch sensation and 2-PD of the thumb, the index finger, the little finger, thenar, and hypothenar were measured (n = 112) using sensory measurement tools. Sensory differences among the hand sites were then compared. The correlation analysis between SEP and the hemiplegic hand function was made. Sensory functions were divided into three levels: sensory intactness, sensory impairment, and sensory loss. Results: Light touch sensations were mainly associated with sensory impairment in the finger and palm region. The 2-PD of the finger region was mainly sensory loss and that of the palm region was mainly sensory impairment. There was no statistical difference in the light touch sensation among the sites of the hand. The correlation coefficients between the 2-PD and SEP N20 amplitudes differed. The correlation coefficients of the thenar and hypothenar were the smallest, and that of the finger was the largest. Light touch sensation and 2-PD in patients with stroke were related to the hemiplegic hand function. Conclusion: Any site on the hand could be selected as the measurement site for light touch sensation. The little finger and hypothenar may be appropriate sites when screening for 2-PD. To improve the patient's recovery they could receive more sensory stimulation of the hand.

18.
Biomed Mater ; 16(4)2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33975301

RESUMO

Cardiomyocyte (CM) transplantation is a promising option for regenerating infarcted myocardium. However, poor cell survival and residence rates reduce the efficacy of cell transplantation. Gelatin (GA) hydrogel as a frequently-used cell carrier is a possible approach to increase the survival rate of CMs. In this study, microbial transglutaminase (mTG) and chemical crosslinkers glutaraldehyde, genipin, and 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide were employed to prepare GA hydrogels. The mechanical properties and degradation characteristics of these hydrogels were then evaluated. Neonatal rat CMs (NRCMs) were isolated and inoculated on the surface of these hydrogels or encapsulated in mTG-hydrogels. Cellular growth morphology and beating behavior were observed. Cellular viability and immunofluorescence were analyzed. Intracellular Ca2+transient and membrane potential propagation were detected using fluorescence dyes (Fluo-3 and di-4-ANEPPS, respectively). Results showed that the chemical crosslinkers exhibited high cytotoxicity and resulted in high rates of cell death. By contrast, mTG-hydrogels showed excellent cell compatibility. The CMs cultured in mTG-hydrogels for a week expressed CM maturation markers. The NRCMs begun independently beating on the third day of culture, and their beating synchronized after a week of culture. Furthermore, intracellular Ca2+transient events with periodicity were observed. In conclusion, the novel mTG-crosslinked GA hydrogel synthesized herein has good biocompatibility, and it supports CM adhesion, growth, and maturation.


Assuntos
Reagentes de Ligações Cruzadas , Gelatina , Hidrogéis , Miocárdio/citologia , Engenharia Tecidual/métodos , Animais , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Gelatina/química , Gelatina/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley
19.
PeerJ ; 9: e11022, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777525

RESUMO

BACKGROUND: Tissue engineering, which involves the selection of scaffold materials, presents a new therapeutic strategy for damaged tissues or organs. Scaffold design based on blends of proteins and polysaccharides, as mimicry of the native extracellular matrix, has recently become a valuable strategy for tissue engineering. OBJECTIVE: This study aimed to construct composite hydrogels based on natural polymers for tissue engineering. METHODS: Composite hydrogels based on blends of gelatin with a polysaccharide component (chitosan or alginate) were produced and subsequently enzyme crosslinked. The other three hydrogels, chitosan hydrogel, sodium alginate hydrogel, and microbial transglutaminase-crosslinked gelatin (mTG/GA) hydrogel were also prepared. All hydrogels were evaluated for in vitro degradation property, swelling capacity, and mechanical property. Rat adipose-derived stromal stem cells (ADSCs) were isolated and seeded on (or embedded into) the above-mentioned hydrogels. The morphological features of ADSCs were observed and recorded. The effects of the hydrogels on ADSC survival and adhesion were investigated by immunofluorescence staining. Cell proliferation was tested by thiazolyl blue tetrazolium bromide (MTT) assay. RESULTS: Cell viability assay results showed that the five hydrogels are not cytotoxic. The mTG/GA and its composite hydrogels showed higher compressive moduli than the single-component chitosan and alginate hydrogels. MTT assay results showed that ADSCs proliferated better on the composite hydrogels than on the chitosan and alginate hydrogels. Light microscope observation and cell cytoskeleton staining showed that hydrogel strength had obvious effects on cell growth and adhesion. The ADSCs seeded on chitosan and alginate hydrogels plunged into the hydrogels and could not stretch out due to the low strength of the hydrogel, whereas cells seeded on composite hydrogels with higher elastic modulus, could spread out, and grew in size. CONCLUSION: The gelatin-polysaccharide composite hydrogels could serve as attractive biomaterials for tissue engineering due to their easy preparation and favorable biophysical properties.

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