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Objective: To explore the effect of simulated gas of thermobaric bomb charge explosion on cognitive function and the related mechanism of damage. Methods: In January 2022, thirty-two SPF rats were selected and randomly divided into control group, exposed group 1, 2 and 3 (the exposure time of the simulated gas of the explosion of the thermobaric bomb charge was 5 min, 10 min and 15 min, respectively) according to random number table method, with 8 rats in each group. The simulated gas of the explosion of the thermobaric bomb charge were CO 0.15%, CO(2) 3%, NO 0.1%, O(2) 15%, and the rest were N(2). After 30 days of exposure, water maze was used to detect the learning and memory function of rats. Golgi staining was used to observe the number distribution and morphological structure of hippocampal neurons in rats. Western blot was used to detect the expression of Tau-5, pSer262, pSer396, pThr181 and pThr231 proteins in rats. Repeated measure ANOVA was used to compare the design data of repeated measure, one-way ANOVA was used for multi-group mean comparison, and LSD method was used for pound-wise comparison. Results: There were significant differences in the results of repeated measurement ANOVA of the water maze localization navigation test (F=80.98, P<0.001), and there was an interaction between the group and the training days (F=2.16, P=0.022). There were significant differences in escape latency of rats at the 2nd, 3rd, 4th and 5th days among all groups (P<0.05). The results of spatial exploration showed that the frequency of rats crossing the platform was significantly different among all groups (F=4.49, P=0.011). The frequency of rats crossing the platform in exposed group 2 and exposed group 3 was lower than that in control group, and the frequency of rats crossing the platform in exposed group 3 was lower than that in exposed group 1 (P<0.05). With the increase of exposure time, the number of hippocampal neurons decreased, and the dendrite spine density of neurons in CA1 region decreased (P<0.05). Compared with the control group, there was no significant difference in the relative expression level of Tau-5 protein in all exposed groups (P>0.05), but the expression level of pSer262 protein was significantly increased (P<0.05). Compared with the control group, the protein expressions of pSer396, pThr181 and pThr231 in exposed group 2 and exposed group 3 were significantly increased (P<0.05) . Conclusion: The simulated gas of the explosion of the thermobaric bomb charge may contribute to the development of cognitive dysfunction by damaging hippocampal neurons with aberrant phosphorylation of Tau proteins.
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Cognición , Explosiones , Hipocampo , Aprendizaje por Laberinto , Ratas Sprague-Dawley , Proteínas tau , Animales , Ratas , Proteínas tau/metabolismo , Masculino , Hipocampo/metabolismo , Fosforilación , Neuronas/metabolismo , Memoria , Traumatismos por Explosión/metabolismoRESUMEN
Objective: To explore the effect of nerve injury in rats by neurobehavioral experiments, in order to provide a model and idea for further clarification of the traumatic brain injury mechanism under explosion exposure. Methods: From May 2021 to August 2022, 160 SPF male rats were randomly divided into four groups, including control group, 60 kPa group (low intensity group), 90 kPa group (medium intensity group) and 120 kPa group (high intensity group). The blast induced traumatic brain injury (bTBI) model of rats was established by using the shock tube platform to simulate the shock wave parameters of the explosion overpressure of 60 kPa, 90 kPa and 120 kPa. Acute observation was carried out after 24 h and 7 d of explosive exposure, and chronic recovery observation was carried out after 28 d and 90 d. The time effect of shock wave brain injury in different situations was discussed by open field, light dark test, active avoidance test. Finally, the results of brain injury in rats were detected by pathological tissue staining. Results: After 24 h explosion exposure, compared with the control group, the rest time of rats in low and high intensity groups increased, the total movement distance decreased, and the number of visits to the camera obscura decreased, with statistical significance (P<0.05). After 7 days of exposure, compared with the control group, the rest time of rats in high intensity group increased, and the number of visits to the obscura decreased, with statistical significance (P<0.05). After 28 and 90 days of exposure, compared with the control group, there were no significant differences in rest time, total exercise distance and times of visiting the camera obscura in all intensity groups (P>0.05). After 24 h of explosive exposure, compared with the control group, the cell morphology of rats in each intensity group was normal, and no inflammatory cell infiltration was observed. Conclusion: In the acute phase (24 h) of blast exposure, rats have no desire to explore the outside world, and shock wave exposure may damage the neurological function of rats.
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Traumatismos por Explosión , Lesiones Traumáticas del Encéfalo , Lesiones Encefálicas , Ratas , Masculino , Animales , Explosiones , Traumatismos por Explosión/patología , Lesiones Encefálicas/patología , Modelos Animales de EnfermedadRESUMEN
The purpose was to discuss the infection status of human parainfluenza virus type 3 (HPIV-3) in children with acute respiratory tract infection(ARTI) in Qingdao, Shandong province, and to analyze the gene characteristics of HPIV-3 hemagglutinin-neuraminidase protein (HN). This study was a cross-sectional study. A total of 1 674 throat swab samples were collected randomly from children with ARTI, in the three hospitals (Qingdao Women and Children's Hospital, West Coast Branch of Affiliated Hospital of Qingdao University, Laoshan Branch of Affiliated Hospital of Qingdao University) from January 2018 to December 2019. Multiplex real-time fluorescence RT-PCR was performed to screen HPIV-3 positive specimens. For HPIV-3 positive specimens, nested PCR was used to amplify the full-length HN gene of HPIV-3. The HN gene was sequenced and compared with the representative strains of HPIV-3 in GenBank, and the phylogenetic tree was established. As results, this study collected 1 674 samples, in which there were 90 HPIV-3 positive samples showed and the detection rate was 5.37%. Among positive specimens, the number of samples from children under 6 years old was 88, accounting for 97.78%. HPIV-3 positive cases were mainly distributed in spring and summer. The full-length sequences of 44 HPIV-3 HN genes were obtained by nested PCR method. Sequence alignment and evolutionary analysis showed that the HPIV-3HN gene belonged to the C3a and C3b branches of C3 genotype, with 30 strains of subtype C3a and 14 strains of subtype C3b. The nucleotide and amino acid homology of the amplified 44 strains of the HPIV-3 HN gene in Qingdao were 97.0%-100.0% and 98.5%-100.0%, respectively. In conclusion, from 2018 to 2019, the C3a and C3b branches of HPIV-3 C3 genotype were circulating prevalent in Qingdao, Shandong province. HN gene variation rate was low, but showed certain regional characteristics in evolution.
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Virus de la Parainfluenza 3 Humana , Infecciones del Sistema Respiratorio , Niño , Preescolar , Estudios Transversales , Femenino , Hemaglutininas , Humanos , Neuraminidasa , Virus de la Parainfluenza 3 Humana/genética , Filogenia , Infecciones del Sistema Respiratorio/epidemiología , Proteínas ViralesRESUMEN
Objective: To evaluated the potential developmental toxicity and teratogenicity of ammonium dinitroamide (ADN) by micromass test (MM Test) and embryonic stem cell test models. Methods: In September 2018, rat embryos were isolated and limb bud cells were collected. The limb bud cells were treated with different concentrations of ADN (0, 312.50, 625.00, 1250.00, 2500.00, 5000.00, 10000.00 µg/ml) . Half proliferation inhibitory concentration and half differentiation inhibitory concentration were calculated and the teratogenic effects were evaluated according to the criteria. For the embryonic stem cell test, the effects of different concentrations of ADN (0, 39.06, 78.13, 156.25, 312.50, 625.00, 1250.00, 2500.00 µg/ml) on the differentiation of mouse embryonic stem cells (mESCs) into myocardial cells and the cytotoxicity of mESCs and 3T3 cells were detected. The embryonic toxicity was evaluated according to the criteria. In this study, both 5-fluorouracil (5-FU) , a known strong embryonic toxic drug, and penicillin-G (P-G) , a non-embryonic toxic drug, were used to verify the effectiveness of the model, and the validated test model was applied to evaluate the embryonic toxicity of ADN. Results: In the MM Test, the inhibition rates of proliferation and differentiation of limb bud cells in ADN groups were higher than that in control group (P<0.05) . And the half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on limb bud cells were 7480.32 and 4526.09 µg/ml, respectively. ADN was determined to be non-teratogenic by standard. In the embryonic stem cell test, the inhibition rates of mESCs proliferation in ADN groups were higher than that in control group, and the inhibition rates of 3T3 cells in 156.25, 312.50, 625.00, 1250.00, 2500.00 µg/ml ADN groups were higher than that in control group (P<0.05) . The half proliferation inhibitory concentration and half differentiation inhibitory concentration of ADN on mESCs were 1851.73 and 1796.39 µg/ml, respectively, and the half proliferation inhibitory concentration on 3T3 cells was 3334.35 µg/ml. ADN was determined to be non-embryotoxic by standard. Conclusion: After evaluation by MM Test and embryonic stem cell models, ADN has no embryo toxicity and is a non-teratogenic substance.
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Células Madre Embrionarias , Esbozos de los Miembros , Animales , Diferenciación Celular , Embrión de Mamíferos , Ratones , Nitritos , Compuestos de Amonio Cuaternario , RatasRESUMEN
OBJECTIVES: To analyze the characteristics of medical malpractices in orthopaedic surgeries, to explore principles and methods in medical legal identification, and to provide basic data for uniform medicolegal standard for the future medical identification. METHODS: A retrospective analysis was conducted on 100 cases of medical malpractices in orthopaedic surgery, among the 364 cases archived in Medicolegal Expertise Center of Xi'an Jiaotong University during 2002-2015. RESULTS: In the 100 cases of orthopedic medical malpractices, with 104 hospitals involved in, 95 cases were judged with medical errors and the other 9 cases with no error. The top 3 reasons for errors were ï¼1ï¼ inadequate observation or estimation of diseases ï¼27.9%ï¼, ï¼2ï¼ intraoperative improper operation ï¼17.3%ï¼, and ï¼3ï¼ delayed or missed diagnosis and treatment ï¼12.5%ï¼. The consequences of medical malpractices were mostly disability ï¼61%ï¼, followed by prolonged diseases ï¼31%ï¼ and death ï¼8%ï¼. With regard to the causal relationship between medical errors and consequences, 95 cases ï¼91.4%ï¼ were with causality and the other 9 cases ï¼8.6%ï¼ with no causality. Specifically, 56 cases ï¼53.9%ï¼ were with medical errors as the secondary causes accounting for 25% causative potency, and 20 cases ï¼19.2%ï¼ were with medical errors as the major causes accounting for 75% causative potency. CONCLUSIONS: It is pivotally important for determining the causative potency of medical errors to analyse the causes of damages in orthopaedic surgery and to distinguish subjective factors from objective ones of medical errors.
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Mala Praxis , Procedimientos Ortopédicos , Ortopedia , Humanos , Errores Médicos , Procedimientos Ortopédicos/efectos adversos , Procedimientos Ortopédicos/normas , Estudios RetrospectivosRESUMEN
Objective: To investigate the effects of simulated-thermobaric explosive gas on the respiration and nervous system in rats. Methods: 70 of SPF SD rats were randomly divided into four thermobaric explosive gas groups, two restoration observation groups and control group from April to August in 2018. The exposure time of in four thermobaric explosive gas groups were 3.75, 7.5, 15.0 and 30 min, respectively. The restoration observation groups were designed to observe for 30 and 120 min after exposure thermobaric explosive gas 30 min. The bloods were collected and analyzed at the end of exposure and recovery observation. The endogenous carbon monoxide (CO) , nitric oxide (NO) , glutamic acid (GLU) , acetylcholinesterase (AchE) and dopamine (DA) were detected in brain tissues, respectively. Results: The blood gas index (pH, PCO(2), PO(2), COHb, O(2)Hb, MeHbt) and blood electrolytes (Na(+), K(+), Ca(2+) and Cl(-)) in exposure groups have significant differences with these in control (P<0.05) . The pH value decreased with the exposure time longer. However, it basically returned to normal level when terminating exposure for 120 min. The concentration of PCO(2), MeHb and CoHb increased first and then decreased with the exposure time extension. Conversely, The PO(2) and O(2)Hb decreased first and then increased with the exposure time longer. The concentration of endogenous CO, GLU, and AchE decreased and NO increased in exposure group 4 and the restoration observation group 1 compared with those in control (P<0.01) . In addition, there were pathological changes in lung and brain tissue of exposure group, such as inflammatory cell infiltration and edema. Conclusion: The blood gas index, electrolytes, neurotransmitter, histopathology of lung and brain were changed to various degrees by thermobaric bomb gas exposure. These findings would provide some beneficial support for evaluating the damage effect of thermobaric bomb gas on organisms.
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Bombas (Dispositivos Explosivos) , Combustibles Fósiles , Sistema Nervioso , Sistema Respiratorio , Animales , Encéfalo/efectos de los fármacos , Química Encefálica/efectos de los fármacos , Combustibles Fósiles/toxicidad , Concentración de Iones de Hidrógeno , Pulmón/efectos de los fármacos , Sistema Nervioso/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Sistema Respiratorio/efectos de los fármacos , Factores de TiempoRESUMEN
Hand-foot-mouth disease (HFMD) is a common pediatric disease responsible for the development of rashes or herpes on the hand, foot, and mouth. Severe complications of HFMD include myocarditis, pulmonary edema, aseptic meningoencephalitis, and even death. Therefore, early diagnosis of HFMD is of particular importance. In this study, we determined the clinical value of the combined detection of liver function and high-sensitivity C-reactive protein (hs-CRP) expression in children with HFMD. Three hundred children with HFMD were recruited to this study between July 2013 and July 2015 and divided into the mild and severe HFMD groups (N = 150 per group). The liver function [aspartate aminotransferase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) levels] and hs-CRP expression were evaluated using standardized tests, and the clinical value of combined detection of these indices (in parallel and serially) was determined. Patients in the severe HFMD group showed significantly higher levels of ALT, AST, ALP, and hs-CRP compared to those in the mild HFMD group (P < 0.05). The hs-CRP and liver function tests had low specificity and sensitivity, respectively. However, parallel combined detection improved the sensitivity and negative predicted value of these indices, whereas serial combined detection improved the specificity and positive predicted value. In conclusion, hs-CRP and liver function play a major role in the diagnosis of HFMD (and identifying its severity), and serial combined detection of these indices enhances the positive predicted value, and could be employed to diagnose severe HFMD at an earlier stage.
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Proteína C-Reactiva/metabolismo , Enfermedad de Boca, Mano y Pie/sangre , Enfermedad de Boca, Mano y Pie/fisiopatología , Niño , Preescolar , Femenino , Humanos , Lactante , Pruebas de Función Hepática , MasculinoRESUMEN
Objective: To investigate skin sensitization of 3, 4-bis (4'-aminofurazano-3') furoxan (DATF) in mice using 5-bromo-2'-deoxyuridine enzyme-linked immunosorbent assay (BrdU-ELISA) . Methods: A total of 30 specific pathogen-free BALB/C mice were randomly divided into high-, medium-, and low-dose DATF groups, positive control group, and solvent control group, with six mice in each group. The mice in the high-, medium-, and low-dose DATF groups were treated with 50%, 25%, and 10% (0.5, 0.25, and 0.10 g/ml) DATF solution, those in the positive control group were treated with 1% 2, 4-dinitrochlorobenzol (DNCB) , and those in the solvent control group were treated with acetone/olive oil (4â¶1) . After treatment, retroauricular lymph nodes were collected and cell suspension was prepared. ELISA was used to measure the level of cell proliferation after the addition of 5-bromo-2'-deoxyuridine (BrdU) , and the BrdU labeling index (LI) and test substance concentration at a stimulation index (SI) of 1.6 (EC1.6) were calculated. Results: There were no significant differences in auricular thickness between groups (P>0.05) , and DAFT did not have skin irritation. Compared with the solvent control group, the high-dose DATF group and the positive control group showed significant increases in the weight of lymph nodes (P<0.05) . Compared with the solvent control group, all the other groups showed significant increases in BrdU LI (P<0.01) . The low-, medium-, and high-dose DATF groups had SIs of 6.1, 8.8, and 12.1, respectively, and the EC1.6 of DATF was 2.2%, which suggested that DATF had strong sensitization. Conclusion: DATF has strong skin sensitization in mice, with reference to the guideline of Organization for Economic Co-operation and Development Item No. 442B (OECD TG 442B) .
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Dermatitis Alérgica por Contacto , Ensayo del Nódulo Linfático Local , Oxadiazoles/toxicidad , Animales , Bromodesoxiuridina , Proliferación Celular , Ensayo de Inmunoadsorción Enzimática , Femenino , Ganglios Linfáticos , Ratones , Ratones Endogámicos BALB C , Distribución Aleatoria , PielRESUMEN
The spin-polarized transport properties of a high-spin-state spin-crossover molecular junction with zigzag-edge graphene nanoribbon electrodes have been studied using density functional theory combined with the nonequilibrium Green's-function formalism. The molecular junction presents integrated spintronic functionalities such as negative differential resistance behavior, spin filter and the spin rectifying effect, associated with the giant magnetoresistance effect by tuning the external magnetic field. Furthermore, the transport properties are almost unaffected by the electrode temperature. The microscopic mechanism of these functionalities is discussed. These results represent a step toward multifunctional molecular spintronic devices on the level of the individual spin-crossover molecule.
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Although many studies have been carried out on monoclonal gammopathy of unknown significances (MGUS), smoldering multiple myeloma (SMM), and multiple myeloma (MM), their classification and underlying pathogenesis are far from elucidated. To discover the relationships among MGUS, SMM, and MM at the transcriptome level, differentially expressed genes in MGUS, SMM, and MM were identified by the rank product method, and then co-expression networks were constructed by integrating the data. Finally, a pathway-network was constructed based on Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, and the relationships between the pathways were identified. The results indicated that there were 55, 78, and 138 pathways involved in the myeloma tumor developmental stages of MGUS, SMM, and MM, respectively. The biological processes identified therein were found to have a close relationship with the immune system. Processes and pathways related to the abnormal activity of DNA and RNA were also present in SMM and MM. Six common pathways were found in the whole process of myeloma tumor development. Nine pathways were shown to participate in the progression of MGUS to SMM, and prostate cancer was the sole pathway that was involved only in MGUS and MM. Pathway-network analysis might provide a new indicator for the developmental stage diagnosis of myeloma tumors.
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Redes Reguladoras de Genes , Redes y Vías Metabólicas , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Transducción de Señal , Biología Computacional , Conjuntos de Datos como Asunto , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Anotación de Secuencia Molecular , Gammopatía Monoclonal de Relevancia Indeterminada/genética , Gammopatía Monoclonal de Relevancia Indeterminada/metabolismo , Gammopatía Monoclonal de Relevancia Indeterminada/patología , Mieloma Múltiple/patología , Paraproteinemias/genética , Paraproteinemias/metabolismo , Paraproteinemias/patologíaRESUMEN
The number of diabetic patients visiting stomatology for periodontal disease is increasing, and the symptoms are relatively severe, and often complications increase the complexity of periodontal treatment. This article briefly describes the research progress and clinical manifestations of the epidemiology and related pathological mechanisms of periodontitis with diabetes, focusing on the treatment and providing reference for stomatologists in the clinical diagnosis and treatment of patients with diabetic periodontitis.
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Complicaciones de la Diabetes , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Enfermedades Periodontales , Periodontitis , Humanos , Periodontitis/complicaciones , Periodontitis/diagnóstico , Periodontitis/terapia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/terapia , Atención Odontológica , Complicaciones de la Diabetes/diagnóstico , Complicaciones de la Diabetes/terapia , Complicaciones de la Diabetes/complicacionesRESUMEN
OBJECTIVES: There is little evidence in the literature about the relationship between frailty and falls in older adults. Our objective was to explore the relationship between frailty and falls, and to analyze the effect factors (e.g., gender, different frailty assessment tools, areas, level of national economic development, and year of publication) of the association between frailty and falls among older adults. DESIGN: Systematic review and meta-analysis. SETTING AND PARTICIPANTS: Cohort studies that evaluated the association between frailty and falls in the older adults were included. We excluded any literature outside of cohort studies. METHODS: We did a systematic literature search of English databases PubMed, Scopus, Web of Science, EBSCOhost, and SciElO, as well as the Chinese databases CNKI, WANFANG, and VIP from 2001 until October 2022. The eligible studies were evaluated for potential bias using the Newcastle-Ottawa Scale (NOS). Study selection, data extraction and assessment of study quality were each conducted by two investigators. In Stata/MP 17.0 software, we calculated pooled estimates of the prevalence of falls by using a random-effects model, Subgroup analysis was conducted based on gender, different frailty assessment tools, areas, level of economic development, and year of publication. The results are presented using a forest plot. RESULTS: Twenty-nine studies were included in this meta-analysis and a total of 1,093,270 participants aged 65 years and above were enrolled. Among the older adults, frailty was significantly associated with a higher risk for falls, compared with those without frailty (combined RR-relative risk = 1.48, 95% CI-confidence interval: 1.27-1.73, I2=98.9%). In addition, the results of subgroup analysis indicated that men had a higher risk for falls than women among the older adults with frailty (RR 1.94, 95% CI: 1.18-3.2 versus RR 1.44, 95% CI: 1.24-1.67). Subgroup analysis by different frailty assessment tools revealed an increased risk of falls in older adults with frailty when assessed using the Frailty Phenotype (combined RR 1.32, 95%CI: 1.17-1.48), FRAIL score (combined RR 1.82, 95%CI: 1.36-2.43), and Study of Osteoporotic Fractures index (combined RR 1.54, 95%CI: 1.10-2.16). Furthermore, subgroup analysis by areas and level of national economic development found the highest fall risk in Oceania (combined RR 2.35, 95%CI: 2.28-2.43) and the lowest in Europe (combined RR 1.20, 95%CI: 1.05-1.38). Developed countries exhibited a lower fall risk compared to developing countries (combined RR 1.44, 95%CI: 1.21-1.71). Analysis by year of publication showed the highest fall risk between 2013-2019 (combined RR 1.79, 95%CI: 1.45-2.20) and the lowest between 2001-2013 (combined RR 1.21, 95%CI: 1.13-1.29). CONCLUSION: Frailty represents a significant risk factor for falls in older adults, with the degree of risk varying according to the different frailty assessment tools employed, and notably highest when using the FRAIL scale. Additionally, factors such as gender, areas, level of national economic development, and healthcare managers' understanding of frailty may all impact the correlation between frailty and falls. Thus, it's imperative to select suitable frailty diagnostic tools tailored to the specific characteristics of the population in question. This, in turn, facilitates the accurate identification of frailty in older adults and informs the development of appropriate preventive and therapeutic strategies to mitigate fall risk.
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Fracturas Óseas , Fragilidad , Femenino , Humanos , Accidentes por Caídas/prevención & control , Fragilidad/epidemiología , Factores de Riesgo , Estudios de CohortesRESUMEN
Chronic refractory wounds and scars caused by abnormal wound repair seriously damage the health of patients and affect their quality of life. At present, there is a lack of simple but effective and economical treatment methods. Adipose-derived stem cells (ASCs), as a kind of mesenchymal stem cells with multi-directional differentiation potential, have been confirmed by several in vivo and in vitro studies to promote wound healing by promoting epithelialization, angiogenesis, immunoregulation, antioxidant properties, and other mechanisms. ASCs and their derivatives have been used in the treatment of refractory wounds caused by burns, diabetic, and radiation injuries with good results achieved. Their potential to become new materials for wound repair has also been confirmed. This paper reviewed the mechanism and clinical application of ASCs in promoting wound repair, and looked into its research direction and prospects.
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Células Madre Mesenquimatosas , Cicatrización de Heridas , Humanos , Cicatrización de Heridas/fisiología , Tejido Adiposo , Calidad de Vida , AdipocitosRESUMEN
High corrosion rate and accumulation of hydrogen gas upon degradation impede magnesium alloys' clinical application as implants. In this work, micro-arc oxidation (MAO) was used to fabricate a porous coating on magnesium alloys as an intermediate layer to enhance the bonding strength of propolis layer. Then the composite coatings were fabricated using sol-gel method by dipping sample into the solution containing propolis and polylactic acid at 40 °C. The corrosion resistance of the samples was determined based on potentiodynamic polarization experiments and immersion tests. Biocompatibility was designed by observing the attachment and growth of wharton's jelly-derived mesenchymal stem cells (WJCs) on substrates with MAO coating and substrates with composite coatings. The results showed that, compared with that of Mg-Zn-Ca alloy, the corrosion current density of the samples with composite coatings decreased from 5.37 × 10â»5 to 1.10 × 10â»6 A/cm² and the corrosion potential increased by 240 mV. Composite coatings exhibit homogeneous corrosion behavior and can promote WJCs cell adhesion and proliferation. In the meantime, pH value was relatively stable during the immersion tests, which may be significant for cellular survival. In conclusion, our results indicate that composite coatings on Mg-Zn-Ca alloy fabricated by MAO/sol-gel method provide a new type bioactive material.
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Aleaciones/química , Calcio/química , Magnesio/química , Zinc/química , Materiales Biocompatibles , Técnicas de Cultivo de Célula , Proliferación Celular , Técnicas Electroquímicas , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Propiedades de SuperficieRESUMEN
Objective: To determine whether amoxicillin had an effect on the enamel mineralization of SD rats. Methods: Eighteen SD rats were randomly divided into three groups. The rats in the control group were given distilled water. The rats in two experimental groups were administered 50 or 100 mg/kg amoxicillin by intragastric administration from day 3 to day 17 after birth. The general condition, the structure of liver and kidney, the enamel surface changes of mandibular first molars and incisors were observed. The changes of Ca/P ratio on enamel surface were analyzed by X-ray energy dispersive spectrometer (EDS). The surface morphology after phosphoric acid treatment was examined by scanning electron microscopy (SEM). Histological changes in the ameloblasts of mandibular incisors were analyzed by hematoxylin and eosin (HE) staining. Results: Compared with the control group, the general conditions as well as liver and kidney structures of SD rats in 50 and 100 mg amoxicillin groups had no significant differences. There was no obvious chalky changes on the first mandibular molars of SD rats in each group. All the incisors in 50 and 100 mg groups showed different degrees of chalkiness in the labial incisal 1/3 enamel. X-ray EDS analysis showed that the Ca/P ratios of occlusal and incisal 1/3 enamel in 50 and 100 mg groups (occlusal 1/3 of mandibular first molars: 1.51±0.03 and 1.52±0.02, incisal 1/3 of mandibular incisors: 1.46±0.01 and 1.43±0.01) was significantly lower than that in the control group (occlusal 1/3 of mandibular first molars: 1.67±0.41, incisal1/3 of mandibular incisors: 1.73±0.07) (P<0.05). However, there was no significant differences in the cervical 1/3 Ca/P ratio of mandibular first molars and incisors among the three groups (mandibular first molars: 1.56±0.04 for control group, 1.59±0.05 for 50 mg group and 1.57±0.04 for 100 mg group; incisors: 1.52±0.02 for control group, 1.47±0.01 for 50 mg group and 1.51±0.03 for 100 mg group) (P>0.05). SEM observation showed that the enamel rods of the first molars and incisors in the 50 and 100 mg group varied in size and arranged disorderly. The spaces between the enamel rods were larger than that in the control group and some areas even appeared large pits. HE staining showed that the gaps between ameloblasts in 50 and 100 mg groups were significantly wider than that in the control group. Conclusions: Intake of amoxicillin during the period of enamel development of SD rats might affect enamel mineralization.
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Amelogénesis , Amoxicilina , Animales , Esmalte Dental , Incisivo , Ratas , Ratas Sprague-DawleyRESUMEN
Objective: To investigate the effect of antibiotics application in perioperative period on carotid artery and serum interluekin-6 (IL-6) in chronic periodontitis (CP) rats with hyperlipidemia (HL) or diabetes mellitus (DM). Methods: The models of CP rats with HL or DM were established in different batches. The rats were divided into groups as follows: A and A' were normal control groups, n=7 in each group; B(HL) and B'(DM) were groups of HL and DM, n=7 in each; C(HL+CP) and C'(DM+CP) were groups of CP with HL and CP with DM, n=21 in each. After the establishment of the models, groups C and C' were divided into C1 and C1' non-intervention group, C2 and C2' simple tooth extraction group and C3 and C3' antibiotic-assisted tooth extraction, with 7 rats in each of the groups. Two time interventions were performed to extract experimental teeth (bilateral maxillary first and second molars) in groups C2, C2', C3 and C3'. Serum samples were collected at 5 time points before and after tooth extraction (T1: before the first tooth extraction; T2: one week after the first tooth extraction; T3, T4, T5: the first, third and fifth week after the second tooth extraction), respectively. The absolute content of IL-6 in serum was detected by enzyme-linked immunosorbent assay (ELISA). Ratio of the absolute content in the experimental groups and control groups were calculated as the relative content of IL-6. At the end of the experiments, all rats were euthanasia and the bifurcation vascular tissues of carotid artery were collected for the observation of the carotid artery pathology and plaque formation and the measurement of the thickness of carotid intimal-medial layer (IMT). Results: Carotid artery pathology observation showed the IMT in group C was significantly thickened and the group C2 was the most thickened one (compared with group A, Pï¼0.01). Elastic fibers in groups C1 and C2 were disordered or even broken and disappeared, presenting typical atherosclerotic plaques, which were diffuse calcium salt deposits in the intimal-medial layers and protrude into the lumen. Elastic fibers in group C3 were ranged in ordered relatively without obvious fracture and the number of plaques was significantly reduced. The vascular walls in rats of groups B' and C' were incomplete, the IMTs had no obvious changes, elastic fibers were ranged disorderly and broken and the smooth muscle cells had vacuolar changes. In group C2', the vascular wall was significantly thinned and calcified plaques appeared in the artery, which showed multiple calcification lesions penetrating through the intimal-medial layer or even the whole layer. The vascular wall of group C3' was integrity and the elastic fibers arranged relatively clutter-free, the number of plaques was reduced. Results of detections of IL-6 showed the relative contents of IL-6 in groups B, B', C1, and C1' increased with time. At T3 time point, the relative contents of IL-6 in groups C2 and C3 reached the peak, C2 was 10.4 times of group A and C3 was 9.5 times of group A, and then decreased to different low levels. At T5 point, comparisons of the relative contents of IL-6 showed C3 < C2 < C1 (3.2 times, 5.4 times, 9.6 times of group A, respectively). The relative contents of IL-6 in groups C2' and C3' reached the peak at T2 point (4.9 times and 4.5 times of group A, respectively), and then decline with time. At T5 point, comparisons of the relative contents of IL-6 showed C3'< C2'< C1' (1.2 times, 1.4 times and 3.1 times of group A, respectively). Conclusions: Blood vessels were observed more obvious thickened in the tooth extraction without antibiotic of HL+CP rats with calcifications increase. Blood vessels of DM+CP rats became thin and fragile and even the integrity was damaged. Perioperative use of antibiotics might reduce the carotid artery lesions and decrease serum levels of inflammatory cytokines.
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Diabetes Mellitus , Hiperlipidemias , Animales , Antibacterianos , Arterias Carótidas , Humanos , Interleucina-6 , Periodo Perioperatorio , Ratas , Ratas Sprague-DawleyRESUMEN
A time evolution analysis is presented for the interaction between the instability waves, shock cells, and screech tones based on the authors' previous numerical simulation database. An attachment and reinforcement process of the upstream propagating screech waves with the downstream hydrodynamic waves is identified and recognized as part of the screech loop. The first five shock cells are recognized as the effective sound source region. Through an analysis of the phase variation in the dominant pressure fluctuations for several typical Mach number screeching jets, it is found that the total number of the instability waves and the upstream feedback sound waves in the effective source region can be identified as 5 for the A1, B, and D modes and 6 for A2 and C modes, respectively. A screech tone frequency prediction formula is thus proposed based on this relation. The predicted screech wavelengths or Strouhal numbers of cold and hot jets all agree well with the experimental data by other researchers, except for a small discrepancy for the B mode. It is also noticed that the measured two A0 modes by Ponton et al. [NASA Technical Memorandum No. 113137, Langley Research Center (1997)] can be classified to A1 and A2 modes, respectively, according to the proposed formula.
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Acústica , Aeronaves , Modelos Teóricos , Ruido del Transporte , Valor Predictivo de las Pruebas , Espectrografía del SonidoRESUMEN
Recent evidence that the cerebellum is involved in perception and cognition challenges the prevailing view that its primary function is fine motor control. A new alternative hypothesis is that the lateral cerebellum is not activated by the control of movement per se, but is strongly engaged during the acquisition and discrimination of sensory information. Magnetic resonance imaging of the lateral cerebellar output (dentate) nucleus during passive and active sensory tasks confirmed this hypothesis. These findings suggest that the lateral cerebellum may be active during motor, perceptual, and cognitive performances specifically because of the requirement to process sensory data.
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Núcleos Cerebelosos/fisiología , Discriminación en Psicología/fisiología , Percepción/fisiología , Desempeño Psicomotor/fisiología , Adulto , Núcleos Cerebelosos/irrigación sanguínea , Circulación Cerebrovascular , Humanos , Imagen por Resonancia Magnética , Masculino , Actividad Motora/fisiología , Estimulación Física , Sensación/fisiología , Tacto/fisiologíaRESUMEN
Background: Epithelial-mesenchymal transition (emt) refers to the biologic process in which epithelial cells are transformed into interstitial phenotypes by specific pathways. This transition plays an important biologic role in the process by which epithelium-derived malignant tumour cells acquire the ability to migrate and invade. We explored the relationship between emt-associated molecules and patient-related clinical factors to determine whether any clinical characteristics could be used as biomarkers for emt-related protein alterations in lung cancer-especially lung adenocarcinoma. Methods: Tumour specimens were collected from 80 patients with lung adenocarcinoma who underwent surgery or lung biopsy, with 4 patients being evaluated a 2nd time after re-biopsy. Expression of emt-related proteins, including E-cadherin and vimentin, was evaluated by immunohistochemistry. We analyzed the relationship between clinicopathologic characteristics and expression level of the emt markers. Results: Positive expression of E-cadherin was observed in 63 patients (79%), and vimentin, in 46 patients (57.5%). No significant relationships between E-cadherin or vimentin expression and smoking history, sex, age, driving gene mutations, or cell differentiation were identified. A significant correlation was observed between vimentin expression and pathologic stage. Of the 4 patients who were evaluated a 2nd time after re-biopsy, 3 showed the same emt-related protein expression status as in the first analysis. In the remaining patient, E-cadherin had changed completely. Conclusions: Clinicopathologic factors in cancer patients did not help to diagnose emt status in lung adenocarcinoma; however, TNM stage might be associated with vimentin expression.