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STUDY DESIGN: Biomechanical testings and finite element analysis. OBJECTIVES: This study aims to investigate how annulus fibrosus (AF) incision size (RIS, Ratio of incision width to AF height) and shape affect intervertebral disc (IVD) biomechanics. METHODS: A validated finite element model of lumbar spines simulated various incisions in the middle-right posterior region of the AF, with different sizes and shapes. Simulations included axial compression, flexion, extension, bending, and rotation. Parameters assessed included stability, re-herniation, and IVD degeneration by analyzing stress, height, Intradiscal pressure (IDP), and the range of motion (ROM). RESULTS: Incision increased AF stress and ROM under 3 Nm moment, with values rising as RIS increased. RIS exceeding 40% resulted in a 20% AF stress increase during compression and extension, while RIS over 50% led to over 20% AF stress increase during other motions. Incision stress also increased with higher RIS, particularly surpassing 50% RIS. IDP rose across all incision shapes. Endplate stress increased (9.9%-48.9%) with larger incisions, with average increases of 12.8%, 12.7%, 30.5%, and 22.8% for circular, oval, square, and rectangular incisions. Compression and rotation minimally affected NP pressure (<15%), while flexion (19.8%-38.8%) and bending (18.5%-43.9%) had a more pronounced effect. ROM increased with RIS (20.0% â¼ 77.4%), especially with an incision RIS exceeding 40%. CONCLUSIONS: AF injury elevates AF stress, reduces spine stability, heightens degeneration risk with increasing RIS. Reherniation risk rises when RIS exceeds 40%. Circular or oval incisions maintain spine biomechanics better than square or rectangular ones.
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OBJECTIVE: With the increase in the prevalence rate and improvements in the survival of breast cancer patients, there is a growing interest in understanding the level of psychosocial adjustment in these patients. The study aimed to describe the illness perception and psychosocial adjustment levels of both breast cancer patients and their spouses, to use the Actor-Partner Interdependence Model (APIM) to clarify the actor-partner relationships between spouses, and to explore the impact of illness perception on psychosocial adjustment to the disease within the joint actions of both spouses. METHODS: A total of 216 female patients with breast cancer and their spouses participated in the study. They were selected from two tertiary hospitals in Guangdong Province, China from October 2022 to May 2023 using a convenience sampling method. The participants were assessed using the Brief Illness Perception Questionnaire and the Psychosocial Adjustment to Illness Scale to examine the relationship between illness perception and psychosocial adjustment. AMOS24.0 was used to test and analyze the actor-partner interdependence model. RESULTS: The illness perception score (57.75 ± 10.91) was slightly higher than that of the spouse (57.10 ± 11.00), and the psychosocial adjustment score (64.67 ± 6.33) was slightly lower than that of the spouse (64.76 ± 7.49). The results of the actor-partner interdependence model indicated that there was a couple partner between breast cancer patients and their spouses: the spouse's illness perception significantly affected the patient's psychosocial adjustment (ß = 0.095, p = 0.015); the patient's illness perception also significantly affected the spouse's psychosocial adjustment (ß = 0.106, p = 0.033). Among them, the patient's psychosocial adjustment was found to be related to the patient's illness comprehensibility or coherence of illness (ß = 0.433, p = 0.009), the spouse's emotional illness representation (ß = 0.218, p = 0.037), and the spouse's illness comprehensibility or coherence of illness (ß = 0.416, p = 0.007), while the spouse's psychosocial adjustment was only related to the spouse's illness comprehensibility or coherence of illness (ß = 0.528, p = 0.007). CONCLUSIONS: The psychosocial adjustment of breast cancer patients is affected by both their own and spouse's illness perception. Therefore, in the future, the healthcare staff can implement early psychological interventions for patients diagnosed with breast cancer and their spouses as a unit to promote the psychosocial adjustment of them.
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Adaptación Psicológica , Neoplasias de la Mama , Esposos , Humanos , Femenino , Esposos/psicología , Neoplasias de la Mama/psicología , Persona de Mediana Edad , Adulto , China , Masculino , Anciano , Encuestas y Cuestionarios , Modelos PsicológicosRESUMEN
Macrophage-hitchhiked arsenic/AB bionic preparations were developed to improve the therapeutic effect on liver cancer by means of the tumor-targeting ability of macrophages in vivo. In vitro and in vivo cellular uptake assays demonstrated that arsenic/AB, with negatively charged particles of around 100-200 nm size, could hitchhike to macrophages. Dissolution experiments of arsenic/AB showed that arsenic/AB could delay the release of arsenic and ensure the safety of macrophages during its transport. Histological examination confirmed the safety of the preparations for major organs. In vivo distribution experiment showed that the arsenic/AB bionic preparations could rapidly accumulate in tumors, and in vivo treatment experiment showed a significant tumor inhibition of arsenic/AB. The therapeutic mechanism of liver cancer might be that the arsenic/AB bionic preparations could inhibit tumor growth by reducing inflammatory response and inhibiting CSF1 secretion to block CSF1R activation to induce more differentiation of tumor-associated macrophages (TAMs) towards the anti-tumor M1 phenotype. Therefore, we concluded that the arsenic/AB bionic preparations could improve the distribution of arsenic in vivo by hitchhiking on macrophages as well as make it have tumor targeting and deep penetration abilities, thus increasing the therapeutic effect of arsenic on liver cancer with reduced side effects.
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Arsénico , Neoplasias Hepáticas , Humanos , Arsénico/farmacología , Biónica , Neoplasias Hepáticas/tratamiento farmacológico , Macrófagos , Fenotipo , Microambiente TumoralRESUMEN
The specific mechanisms by which acupuncture affects the central nervous system are unclear. In the International Standard Scalp Acupuncture system, acupuncture needles are applied at the middle line of the vertex, anterior parietal-temporal oblique line, and the posterior parietal-temporal oblique line. We conducted a single-arm prospective clinical trial in which seven healthy elderly volunteers (three men and four women; 50-70 years old) received International Standard Scalp Acupuncture at MS5 (the mid-sagittal line between Baihui (DU20) and Qianding (DU21)), the left MS6 (line joining Sishencong (EX-HN1) and Xuanli (GB6)), and the left MS7 (line joining DU20 and Qubin (GB7)). After acupuncture, resting-state functional magnetic resonance imaging demonstrated changes in the fractional amplitude of low frequency fluctuations and regional homogeneity in various areas, showing remarkable enhancement of regional homogeneity in the bilateral anterior cingulate, left medial frontal gyrus, supramarginal gyrus, right middle frontal gyrus, and inferior frontal gyrus. Functional connectivity based on a seed region at the right middle frontal gyrus (42, 51, 9) decreased at the bilateral medial superior frontal gyrus. Our data preliminarily indicates that the international standard scalp acupuncture in healthy elderly participants specifcally enhances the correlation between the brain regions involved in cognition and implementation of the brain network regulation system and the surrounding adjacent brain regions. The study was approved by the Ethics Committee of the China-Japan Union Hospital at Jilin University, China, on July 18, 2016 (approval No. 2016ks043).
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Enfermedades Cardiovasculares/diagnóstico por imagen , Sistema Cardiovascular/anatomía & histología , Medicina de Precisión/métodos , Impresión Tridimensional , Enfermedades Cardiovasculares/terapia , Humanos , Medicina de Precisión/tendencias , Impresión Tridimensional/tendencias , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/tendenciasRESUMEN
OBJECTIVES: To evaluate the efficacy and safety of combined selective serotonin reuptake inhibitors (SSRIs) and electroacupuncture therapies for the early treatment of primary depression. METHODS: Randomized controlled trials (RCTs) were analyzed to compare therapy combining SSRIs and electroacupuncture to SSRI therapy alone. The RCTs were identified by searching, among others, PubMed, the Cochrane Library, the Chinese National Knowledge Infrastructure, the Chongqing VIP database for Chinese Technical Periodicals, WANFANG DATA, and the Chinese Biological Medical Literature Database. Scores from Self-Rated Depression Scale (SDS), the Hamilton Depression Scale (HAMD), the Side Effect Rating Scale (SERS), and the Treatment Emergent Symptom Scale (TESS) were analyzed and coded by two independent investigators and used to evaluate the safety and efficacy of treatment. Statistical analyses were performed using RevMan 5.2 software. RESULTS: Six RCTs were analyzed. The meta-analysis revealed that the combined therapy of SSRIs and electroacupuncture were associated with superior scores on the HAMD, SDS, and SERS measures compared with SSRIs alone after 1-4 weeks of treatment: HAMD scores, mean difference (MD)(1 week), 2.32 (95% confidence interval [CI](1 week), 1.47-3.16, p(1 week)<0.00001); MD(2 weeks), 2.65 (95% CI(2 weeks), 1.81- 3.50, p(2 weeks)<0.00001); MD(4 weeks), 2.70 (95% CI(4 weeks), 1.90-3.51, p(4 weeks)<0.00001); SDS scores: MD(1 week), 3.13 (95% CI(1 week), 1.22-5.03, p(1 week) = 0.001); MD(2 weeks), 4.05 (95% CI(2 weeks), 0.22-7.87, p(2 weeks) = 0.04); MD(4 weeks), 5.02 (95% CI(4 weeks), 1.61-8.43, p(4 weeks) = 0.004); SERS scores: MD(2 weeks), 2.20 (95% CI(2 weeks), 1.43-2.96, p(2 weeks)<0.00001); MD(4 weeks), 2.12 (95% CI(4 weeks), 1.42-2.83, p(4 weeks)<0.00001). However, two of the aforementioned outcomes were rated as medium quality because of heterogeneity, as assessed using the Grading of Recommendations Assessment, Development and Evaluation system. CONCLUSIONS: The available evidence suggests that the early treatment of primary depression using both SSRI and electroacupuncture therapies is more efficient than treatments with SSRIs alone and leads to a better and earlier control of depressive symptoms.
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Depresión/terapia , Electroacupuntura , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , HumanosRESUMEN
Acupuncture can induce changes in the brain. However, the majority of studies to date have focused on a single acupoint at a time. In the present study, we observed activity changes in the brains of healthy volunteers before and after acupuncture at Taichong (LR3) and Taixi (KI3) using resting-state functional magnetic resonance imaging. Fifteen healthy volunteers underwent resting-state functional magnetic resonance imaging of the brain 15 minutes before acupuncture, then received acupuncture at Taichong and Taixi using the nail-pressing needle insertion method, after which the needle was retained in place for 30 minutes. Fifteen minutes after withdrawal of the needle, the volunteers underwent a further session of resting-state functional magnetic resonance imaging, which revealed that the amplitude of low-frequency fluctuation, a measure of spontaneous neuronal activity, increased mainly in the cerebral occipital lobe and middle occipital gyrus (Brodmann area 18/19), inferior occipital gyrus (Brodmann area 18) and cuneus (Brodmann area 18), but decreased mainly in the gyrus rectus of the frontal lobe (Brodmann area 11), inferior frontal gyrus (Brodmann area 44) and the center of the posterior lobe of the cerebellum. The present findings indicate that acupuncture at Taichong and Taixi specifically promote blood flow and activation in the brain areas related to vision, emotion and cognition, and inhibit brain areas related to emotion, attention, phonological and semantic processing, and memory.
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BACKGROUND: Although a few studies have been reported on predictive factors of postoperative diabetes remission, the conclusions remain inconsistent. This meta-analysis aimed to assess the preoperative clinical factors for type 2 diabetes mellitus (T2DM) remission after bariatric surgery. METHODS: The Cochrane Library, PubMed, MEDLINE, Embase, and CINAHL databases were searched. All human studies published in English between 1 January 1992 and 1 September 2013 reporting on the parameters of interest were included. RESULTS: In total, 15 studies involving 1,753 bariatric surgery patients were selected. Analyses were performed separately for the parameters of interest. T2DM remission was observed to be negatively correlated with age, diabetes duration, insulin use, and HbA1c levels. Baseline body mass index (BMI) and C-peptide levels were positively associated with the remission rate in Asian patients. However, there was no significant association between gender and remission rate. CONCLUSIONS: Patients with younger age, short diabetes duration, better glucose control, and better ß cell function were more likely to achieve T2DM remission after bariatric surgery. However, further randomized controlled trials with uniform remission criteria should be conducted to provide more reliable evidence.
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Diabetes Mellitus Tipo 2/cirugía , Adulto , Factores de Edad , Cirugía Bariátrica , Glucemia/análisis , Diabetes Mellitus Tipo 2/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Inducción de Remisión , Factores de TiempoRESUMEN
The needling sensation of Deqi during acupuncture is a key factor of influencing acupuncture outcome. Recent studies have mainly focused on the brain function effects of Deqi in a physiological state. Functional magnetic resonance imaging (fMRI) on the effects of acupuncture at Waiguan (SJ5) in pathological and physiological states is controversial. In this study, 12 patients with ischemic stroke received acupuncture at Waiguan (SJ5) and simultaneously underwent fMRI scanning of the brain, with imaging data of the activated areas obtained. Based on the patient's sensation, imaging data were allocated to either the Deqi group or non-Deqi group. In the Deqi group, the activated/deactivated areas were the left superior temporal gyrus (BA39)/right anterior lobe of the cerebellum and left thalamus. In the non-Deqi group, the activated areas included the medial frontal gyrus of the right frontal lobe (BA11), right limbic lobe (BA30, 35), and left frontal lobe (BA47), while the only deactivated area was the right parietal lobe (BA40). Compared with the non-Deqi group, the Deqi group exhibited marked activation of the right anterior lobe of the cerebellum and right limbic lobe (BA30). These findings confirm that the clinical effect of Deqi during acupuncture is based on brain functional changes. Cerebellar activation may be one of the central mechanisms of acupuncture in the treatment of ischemic stroke.
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This study aims to investigate the clinical efficacy of Dextran 40 plus dexamethasone on the prevention of fat embolism syndrome (FES) in high-risk patients with long bone shaft fractures. According to the different preventive medication, a total of 1837 cases of long bone shaft fracture patients with injury severity score (ISS) > 16 were divided into four groups: dextran plus dexamethasone group, dextran group, dexamethasone group and control group. The morbidity and mortality of FES in each group were analyzed with pairwise comparison analysis. There were totally 17 cases of FES and 1 case died. The morbidity of FES was 0.33% in dextran plus dexamethasone group and significantly lowers than that of other groups (P < 0.05). There was no significant difference among other groups (P > 0.05). Conclusion from our data is dextran 40 plus dexamethasone can effectively prevent long bone shaft fractures occurring in high-risk patients with FES.
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BACKGROUND: Postoperative gastroparesis syndrome (PGS) which is mainly manifested as delayed gastric emptying is often caused by upper abdominal and sometimes lower abdominal surgery. In view of the side effects of drugs therapy, the search of supplementary and alternative has been of increasing interest. OBJECTIVE: This paper included a systematic review and meta-analysis on the use of acupuncture and acupoints selection in PGS. Quality for meta-analysis was evaluated using GRADE while each trial was assessed with CONSORT and STRICTA for TCM. METHODS: Randomized controlled trials (RCTs) comparing acupuncture with non-acupuncture treatment were identified from databases PubMed, EBSCO, Ovid, Cochrane, CNKI and Wanfangdata. Meta-analysis on eligible studies was performed using fixed-effects model with RevMan 5.2. Results were expressed as relative risk (RR) for dichotomous data, and 95% confidence interval (CI) were calculated. RESULTS: Of the 348 studies reviewed, 16 RCTs met the inclusion criteria for review while 7 RCTs, 188 patients (intervention) and 182 patients (control) met the criteria for meta-analysis. Both acupuncture and acupuncture combined with medication showed significant higher total effective rate than control (usual care/medication); with (RR 1.27, 95% CI 1.13, 1.44; P<0.0001) and (RR 1.37, 95% CI 1.18, 1.58; P<0.0001) respectively. All included RCTs reported positive effect of acupuncture in PGS treatment. ST36, CV12 and PC6 seemed to be the common acupoints selected. CONCLUSIONS: The results suggested acupuncture might be effective to improve PGS, however, a definite conclusion could not be drawn due to low quality of trials. Further large-scale, high-quality randomized clinical trials are needed to validate this. STUDY REGISTRATION: PROSPERO CRD42013005485.
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Terapia por Acupuntura , Gastroparesia/terapia , Complicaciones Posoperatorias/terapia , Puntos de Acupuntura , Adulto , Anciano , Femenino , Gastroparesia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Resultado del TratamientoRESUMEN
BACKGROUND: Acupuncture therapy for preventive and treatment of postoperative nausea and vomiting(PONV), a condition which commonly present after anaesthesia and surgery is a subject of growing interest. OBJECTIVE: This paper included a systematic review and meta-analysis on the effect of different type of acupuncture and acupoint selection in PONV prevention and treatment. METHODS: Randomised controlled trials(RCTs) comparing acupuncture with non-acupuncture treatment were identified from databases PubMed, Cochrane, EBSCO, Ovid, CNKI and Wanfangdata. Meta-analysis on eligible studies was performed using fixed-effects model with RevMan 5.2. Results were expressed as RR for dichotomous data, with 95%CI. RESULTS: Thirty RCTs, 1276 patients (intervention) and 1258 patients (control) were identified. Meta-analysis showed that PC6 acupuncture significantly reduced the number of cases of early vomiting (postoperative 0-6h) (RR=0.36, 95%CI 0.19,0.71; P=0.003) and nausea (postoperative 0-24h) (RR=0.25, 95%CI 0.10,0.61; P=0.002), but not early nausea (postoperative 0-6h) (RR=0.64, 95%CI 0.34,1.19; P=0.150) and vomiting (postoperative 0-24h) (RR=0.82, 95%CI 0.48,1.38; P=0.450). PC6 acupressure significantly reduced the number of cases of nausea (RR=0.71, 95%CI 0.57,0.87; P=0.001) and vomiting (RR=0.62, 95%CI 0.49,0.80; P=0.000) at postoperative 0-24h. PC6 electro-acupoint stimulation significantly reduced the number of cases of nausea (RR=0.49, 95%CI 0.38,0.63; P<0.000) and vomiting (RR=0.50, 95%CI 0.36,0.70; P<0.000) at postoperative 0-24h. Stimulation of PC6 with other acupoint(s) significantly reduced the number of cases of nausea and vomiting (RR=0.29, 95%CI 0.17,0.49; P<0.000) at postoperative 0-24h. Stimulation of other acupoint(s)(non PC6) also significantly reduced the number of cases of nausea and vomiting (RR=0.63, 95%CI 0.49,0.81; P=0.000) at postoperative 0-24h. However, the quality of study was generally low in studies of PC6 combined with other acupoint(s) and other acupoint(s). Details of blinding were not reported in most reports. CONCLUSIONS: Besides PC6, PC6 combined with other acupoint(s) and other alternative acupoint(s) might be beneficial in prevention and treatment of PONV, the evidence justifies future high-quality studies.
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Terapia por Acupuntura , Náusea y Vómito Posoperatorios/terapia , Terapia por Acupuntura/métodos , Antieméticos/uso terapéutico , Humanos , Oportunidad Relativa , Resultado del TratamientoRESUMEN
Hemangiopoietin (HAPO) is a novel growth factor stimulating the proliferation of hematopoietic and endothelial progenitor cells in vitro and in vivo. The native protein is a 294amino acid multimodular protein. The Nterminus constitutes of two somatomedin B (SMB) homology domains that contain 14 cysteines. The central region is a putative heparinbinding domain (pHBD) and the Cterminus contains mucinlike repeats. In the present study, we demonstrated that prokaryotic recombinant human HAPO (rhHAPO) selfassociates into a multimeric form with a mass weight of ~129 kDa, suggesting a homologous tetramer. rhHAPO in its multimeric form was found to be more stable and more potent in promoting HESS5 cell adhesion. Multimeric rhHAPO had a higher affinity to heparin compared with its dimeric form, although there was no significant conformational change. Cterminal repeats-truncated rhHAPO (rhHAPOΔmucin) was also found to be assembled into a multimer, while deletion of pHBD (rhHAPOΔmucinpHBD) caused the protein to remain in a dimeric form, demonstrating that SMB domains participate in selfaggregation of the molecule and that the pHBD region promotes the tetramerization.
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Heparina/metabolismo , Proteoglicanos/metabolismo , Adhesión Celular/efectos de los fármacos , Dicroismo Circular , Dimerización , Humanos , Unión Proteica , Multimerización de Proteína , Estructura Terciaria de Proteína , Proteoglicanos/química , Proteoglicanos/genética , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologíaRESUMEN
ß-N-acetyl-D-glucosaminidase (NAGase) is a major member in chitinolytic enzymes system, which plays an important role in the hatching and molting processes of marine organism. The effects of guanidinium chloride (GuHCl) on the activity of NAGase from green crab (Scylla serrata) were investigated in this study. In results, GuHCl causes reversible inactivation of the enzyme at below 0.8 M concentrations, and the IC50 is estimated to be 0.15 M. The relationship between the enzyme activity and conformation was charaterized by monitoring the change of protein fluorescence spectra. With increasing GuHCl concentration, the fluorescence intensity of the enzyme distinctly decreases , and the maximal emission peaks appear red-shifted (from 338 nm to 343 nm). The enzyme inactivation precedes conformational changes, indicating that the enzyme active site is more flexible than the whole enzyme molecule. The result of the kinetics of inactivation shows that the value of k(+0) is larger than that of k(+0)'. It suggests that the substrate could protect the enzyme to a certain extent during guanidine denaturation. Our results provide important new insights in marine organism culture, especially in crustacean growth.
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Acetilglucosaminidasa/química , Braquiuros/enzimología , Guanidina/farmacología , Acetilglucosaminidasa/metabolismo , Animales , Activación Enzimática/efectos de los fármacos , Cinética , Desnaturalización Proteica/efectos de los fármacos , Espectrometría de FluorescenciaRESUMEN
BACKGROUND: Ghrelin, a novel endogenous ligand for the growth hormone secretagogue receptor, is considered to implicate the development of the type 2 diabetes mellitus (T2DM). The Leu72Met (+408C>A) polymorphism of the preproghrelin, has been linked to obesity, insulin resistance and diabetes. OBJECTIVE: To investigate the distribution of ghrelin gene Leu72Met polymorphism and its association with the type 2 diabetes mellitus in Chinese population. METHODS: We conducted a case-control study on 877 patients with T2DM and 864 controls, which were genotyped by the polymerase chain reaction (PCR) technique, denaturing high performance liquid chromatography (DHPLC) and DNA sequence analysis. Laboratory analyses were carried out in the hospital laboratory. RESULTS: No significant difference in the Leu72Met genotype distributions and allele frequency was observed between type 2 diabetes mellitus and controls (both P>0.05). The polymorphism was not associated with T2DM. However, among the T2DM group, the patients carrying Leu72Leu genotype had significantly increased levels of FPG and serum creatinine compared with variant genotypes (Leu72Met and Met72Met) (P<0.05). In the control group, the subjects with variant genotypes had significantly increased levels of FINS, HOMA-IR compared with Leu72Leu genotype (P<0.05). CONCLUSION: The Leu72Met polymorphism of the preproghrelin gene was not associated with T2DM in Chinese population. However, it may have some roles in the etiology of insulin resistance.
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Diabetes Mellitus Tipo 2/genética , Ghrelina/genética , Leucina/genética , Metionina/genética , Polimorfismo Genético , Secuencia de Bases , Estudios de Casos y Controles , China , Cromatografía Líquida de Alta Presión , Cartilla de ADN , Ghrelina/química , Humanos , Leucina/química , Metionina/química , Reacción en Cadena de la PolimerasaRESUMEN
Heavy metal pollution such as chromium and zinc in the seawater has been increasing in recent years in the China Sea. Marine shellfish such as prawn and crab are sensitive to this pollution. Beta-N-acetyl-d-glucosaminidase (NAGase, EC 3.2.1.52) catalyzes the cleavage the oligomers of N-acetylglucosamine (NAG) into the monomer. In this study, taking p-nitrophenyl-N-acetyl-beta-d-glucosaminide (pNP-NAG) as substrate, the effects of Zn(2+) on NAGase from green crab ( Scylla serrata ) have been studied. The results showed that appropriate concentrations of zinc could lead to reversible inhibition on the enzyme, and the IC(50) has been estimated to be 0.5 +/- 0.012 mM. Furthermore, it has been shown that Zn(2+) could reduce the thermal stability of NAGase depending on the concentration of Zn(2+). The inhibitory kinetics of zinc on the enzyme in the appropriate concentrations has been studied using the kinetic method of substrate reaction. The inhibition model has been set up, and the rate constants have been determined. The results showed that Zn(2+) was a mixed-type inhibitor of NAGase and that it could combine at the free enzyme and the enzyme-substrate active sites.
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Acetilglucosaminidasa/química , Braquiuros/enzimología , Inhibidores Enzimáticos/farmacología , Zinc/farmacología , Acetilglucosaminidasa/antagonistas & inhibidores , Animales , Braquiuros/química , Dominio Catalítico , CinéticaRESUMEN
Beta-N-acetyl-D-glucosaminidase (NAGase, EC.3.2.1.52), which catalyzes the cleavage of N-acetylglucosamine polymers, is a composition of chitinase and cooperates with endo-chitinase and exo-chitinase to disintegrate chitin into N-acetylglucosamine (NAG). In this investigation, A NAGase from green crab (Scylla serrata) was purified and the effects of dioxane on the enzyme activity for the hydrolysis of p-Nitrophenyl-N-acetyl-beta-D-glucosaminide (pNP-NAG) were studied. The results show that appropriate concentrations of dioxane can lead to reversible inactivation of the enzyme and the inactivation is classified as mixed type. The value of IC50, the dioxane (inactivator) concentration leading to 50% activity lost, is estimated to be 0.68%. The kinetics of inactivation of NAGase in the appropriate concentrations of dioxane solution has been studied using the kinetic method of the substrate reaction. The rate constants of inactivation have been determined. The results showed that k+0 is much larger than k'+0, indicating the free enzyme molecule is more fragile than the enzyme-substrate complex in the dioxane solution. It is suggested that the presence of the substrate offers marked protection of this enzyme against inactivation by dioxane.
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Acetilglucosaminidasa/química , Proteínas de Artrópodos/química , Braquiuros/enzimología , Dioxanos/química , Solventes/química , Acetilgalactosamina/análogos & derivados , Acetilgalactosamina/química , Acetilglucosaminidasa/antagonistas & inhibidores , Animales , Proteínas de Artrópodos/antagonistas & inhibidores , Hidrólisis , Cinética , SolucionesRESUMEN
Serum retinal binding protein 4 (RBP4) was recently described as a new liver- and adipocyte-derived signal that may contribute to Type 2 diabetes mellitus (T2DM) and insulin resistance. The aim of this study was to test whether the RBP4 gene could be used as a genetic marker to predict the development of T2DM amongst the Chinese population of Han. For this study, a normal control group of 115 healthy subjects and an experimental group of 107 patients with T2DM were examined. A combined method of denaturing high-performance liquid chromatography (DHPLC) and sequencing was applied to the detection of the RBP4 gene variants. Two SNPs, rs17484721 and rs36035572, were analyzed. Phenotypes and biochemical indicators related to the metabolism of glucose and lipid were measured. We found that there are significant differences between the control group and the patients group in terms of their respective distributions of genotype and allele frequency. The TG levels of the TT and II genotype was significantly higher than that of the TC + CC and ID + DD, respectively, in both patient group and control group. These findings suggest that the variations in the RBP4 gene may be associated with T2DM and serum triglyeride levels in the Han Chinese.
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Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleótido Simple , Proteínas Plasmáticas de Unión al Retinol/genética , Adulto , Secuencia de Bases , Estudios de Casos y Controles , China , Cromatografía Líquida de Alta Presión/métodos , Análisis Mutacional de ADN/métodos , Diabetes Mellitus Tipo 2/sangre , Femenino , Frecuencia de los Genes , Ligamiento Genético/fisiología , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Triglicéridos/sangreRESUMEN
AIMS: The sterol regulatory element-binding protein (SREBP)-1c gene has been identified as a susceptibility gene in metabolic diseases such as type 2 diabetes mellitus (T2DM), obesity, dyslipidemia and insulin resistance. Previous studies suggest that SNP17 (rs2297508, exon18c and G952G) of SREBP-1c gene and a common SREBP-1c SNP6 (rs11868035) are associated with an increased risk of T2DM. The present study aimed to confirm the previously reported association in a Chinese population and to examine the two SREBP-1c SNPs for their associations with insulin resistance and blood lipid. METHODS: We genotyped two SREBP-1c SNPs in a case-control study (n=327) from Chinese, including 156 patients with T2DM and 171 healthy controls, using polymerase chain reaction-denaturing high-performance liquid chromatography (PCR-DHPLC) and tested for association with type 2 diabetes, insulin resistance and blood lipid, respectively. Genotype and allele distributions and haplotype construction were analysed. RESULTS: The genotype and allele distributions of rs2297508 and rs11868035 polymorphisms were significantly different in type 2 diabetic patients compared to controls (P=0.002 and P=0.013; 0.00 and 0.001, respectively). Haplotype analyses showed significant association with diabetes risk and confirmed the results of the single SNP analyses. The plasma levels of LDL-c of the minor allele-C carriers of the two SNPs were both significantly higher than the noncarriers in the control group (P<0.05). Furthermore, insulin resistance index (HOMA-IRI) of the rare homozygotes C/C of rs11868035 was significantly lower than that of T/T in the T2DM group (P<0.05). CONCLUSIONS: These findings indicate that the SREBP-1c SNPs rs2297508 and rs11868035 are associated with a significantly increased risk of T2DM and dyslipidemia in the Chinese population. Moreover, the SNP (rs11868035) is closely related to insulin resistance (IR) in diabetic patients.
Asunto(s)
Diabetes Mellitus Tipo 2/genética , Resistencia a la Insulina/genética , Polimorfismo de Nucleótido Simple , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Anciano , Pueblo Asiatico/genética , China , Diabetes Mellitus Tipo 2/etnología , Femenino , Frecuencia de los Genes , Genotipo , Haplotipos , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Based on the four TM images of Naiman Banner in Inner Mongolia in 1975, 1985, 1995 and 2005, the extent and relative rate of land use change were used as the indices to analyze the regional difference of land use/cover change in the farming-pasturing zone of Naiman Banner, and the indices abundance and importance value were adopted to analyze the spatial distribution features of land use/cover change in the study area. The results showed that from 1975 to 2005, the types of land use/cover became diversified. The annual change rate was high, and the regional difference was significant. In the northern alluvial plain sub-area, woodland area increased rapidly and largely, while sandy land area decreased obviously. The changing speed of the areas of meadow and sandy land was the fastest, while that of residential area was the slowest. The main forms of land conversion were the conversion from sandy land to cropland and woodland. In the middle sandy land sub-area, sandy land had a wide distribution. The changes of other land use types were comparatively small, and the main form of land conversion was the inter-conversion between cropland and sandy land. In southern loess sub-area, cropland was the dominant land use type and had the smallest change, meadow and sandy land changed most quickly, and the conversion from meadow to cropland and woodland was the most important land conversion form. Natural factors determined the principal characteristics of land use structure in each sub-area of the study area, and artificial factors determined the changing trends of each land use type in each sub-area.