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1.
Biomed Phys Eng Express ; 9(6)2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37820600

RESUMO

Low-intensity transcranial ultrasound stimulation, a novel neuromodulation technique, that possesses the advantages of non-invasiveness, high penetration depth, and high spatial resolution, has achieved positive neuromodulation effects in animal studies. But the regulatory mechanism remains controversial. The intramembrane cavitation effect is considered one of the mechanisms for ultrasound neuromodulation. In this study, the modified equations of ultrasonic cavitation bubble dynamics were coupled with the dual-coupled neuron Hindmarsh-Rose model, small-world neural network model, and the Jansen-Rit neural mass model, which simulate simple coupled neurons, complex neuronal networks, and discharge signals in epileptic disorders respectively. The results demonstrated that ultrasound stimulation has an appreciable modulatory effect on neuronal firing desynchronization in Hindmarsh-Rose model and small-world neural network model. The desynchronization effect is related to the stimulation frequency and intensity. Furthermore, ultrasound stimulation has an inhibitory effect on epileptic seizures, and the effect is enhanced by increasing ultrasound frequency from 0.1-1.0 MHz. This is the first combination of ultrasonic intramembrane cavitation effect theory with neurons and neural network firing desynchronization, which can provide guidance of parametric and theories support for the studies of neurological diseases such as epilepsy and Parkinson's disease.


Assuntos
Epilepsia , Doença de Parkinson , Animais , Neurônios/fisiologia , Epilepsia/diagnóstico por imagem , Epilepsia/terapia , Convulsões
2.
World J Clin Cases ; 11(21): 5083-5096, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37583846

RESUMO

BACKGROUND: Progressive pancreatic ß cell dysfunction is a fundamental aspect of the pathology underlying type 2 diabetes mellitus (T2DM). Recently, mesenchymal stem cell (MSC) transplantation has emerged as a new therapeutic method due to its ability to promote the regeneration of pancreatic ß cells. However, current studies have focused on its efficacy, and there are few clinical studies on its safety. AIM: To evaluate the safety of human umbilical cord (hUC)-MSC infusion in T2DM treatment. METHODS: An open-label and randomized phase 2 clinical trial was designed to evaluate the safety of hUC-MSC transplantation in T2DM in a Class A hospital. Ten patients in the placebo group received acellular saline intravenously once per week for 3 wk. Twenty-four patients in the hUC-MSC group received hUC-MSCs (1 × 106 cells/kg) intravenously once per week for 3 wk. Diabetic clinical symptoms and signs, laboratory findings, and imaging findings were evaluated weekly for the 1st mo and then at weeks 12 and 24 post-treatment. RESULTS: No serious adverse events were observed during the 24-wk follow-up. Four patients (16.7%) in the hUC-MSC group experienced transient fever, which occurred within 24 h after the second or third infusion; this did not occur in any patients in the placebo group. One patient from the hUC-MSC group experienced hypoglycemic attacks within 1 mo after transplantation. Significantly lower lymphocyte levels (weeks 2 and 3) and thrombin coagulation time (week 2) were observed in the hUC-MSC group compared to those in the placebo group (all P < 0.05). Significantly higher platelet levels (week 3), immunoglobulin levels (weeks 1, 2, 3, and 4), fibrinogen levels (weeks 2 and 3), D-dimer levels (weeks 1, 2, 3, 4, 12, and 24), and neutrophil-to-lymphocyte ratios (weeks 2 and 3) were observed in the hUC-MSC group compared to those in the placebo group (all P < 0.05). There were no significant differences between the two groups for tumor markers (alpha-fetoprotein, carcinoembryonic antigen, and carbohydrate antigen 199) or blood fat. No liver damage or other side effects were observed on chest X-ray. CONCLUSION: Our study suggested that hUC-MSC transplantation has good tolerance and high safety in the treatment of T2DM. It can improve human immunity and inhibit lymphocytes. Coagulation function should be monitored vigilantly for abnormalities.

3.
World J Diabetes ; 13(10): 877-887, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36312002

RESUMO

BACKGROUND: Progressive pancreatic ß-cell dysfunction is a fundamental part of the pathology of type 2 diabetes mellitus (T2DM). Cellular therapies offer novel opportunities for the treatment of T2DM to improve the function of islet ß-cells. AIM: To evaluate the effectiveness and safety of human umbilical cord-mesenchymal stem cell (hUC-MSC) infusion in T2DM treatment. METHODS: Sixteen patients were enrolled and received 1 × 106 cells/kg per week for 3 wk as intravenous hUC-MSC infusion. The effectiveness was evaluated by assessing fasting blood glucose, C-peptide, normal glycosylated hemoglobin A1c (HbA1c), insulin resistance index (homeostatic model assessment for insulin resistance), and islet ß-cell function (homeostasis model assessment of ß-cell function). The dosage of hypoglycemic agents and safety were evaluated by monitoring the occurrence of any adverse events (AEs). RESULTS: During the entire intervention period, the fasting plasma glucose level was significantly reduced [baseline: 9.3400 (8.3575, 11.7725), day 14 ± 3: 6.5200 (5.2200, 8.6900); P < 0.01]. The HbA1c level was significantly reduced on day 84 ± 3 [baseline: 7.8000 (7.5250, 8.6750), day 84 ± 3: 7.150 (6.600, 7.925); P < 0.01]. The patients' islet ß-cell function was significantly improved on day 28 ± 3 of intervention [baseline: 29.90 (16.43, 37.40), day 28 ± 3: 40.97 (19.27, 56.36); P < 0.01]. The dosage of hypoglycemic agents was reduced in all patients, of whom 6 (50%) had a decrement of more than 50% and 1 (6.25%) discontinued the hypoglycemic agents. Four patients had transient fever, which occurred within 24 h after the second or third infusion. One patient (2.08%) had asymptomatic nocturnal hypoglycemia after infusion on day 28 ± 3. No liver damage or other side effects were reported. CONCLUSION: The results of this study suggest that hUC-MSC infusion can improve glycemia, restore islet ß-cell function, and reduce the dosage of hypoglycemic agents without serious AEs. Thus, hUC-MSC infusion may be a novel option for the treatment of T2DM.

4.
J Neural Eng ; 19(3)2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35700694

RESUMO

Objective. We propose a closed-loop transcranial ultrasound stimulation (TUS) with a fuzzy controller to realize real-time and precise control of the motor response and neural activity of mice.Approach. The mean absolute value (MAV) of the electromyogram (EMG) and peak value (PV) of the local field potential (LFP) were measured under different ultrasound intensities. A model comprising the characteristics of the MAV of the EMG, PV of the LFP, and ultrasound intensity was built using a neural network, and a fuzzy controller, proportional-integral-derivative (PID) controller, and immune feedback controller were proposed to adjust the ultrasound intensity using the feedback of the EMG MAV and the LFP PV.Main results. In simulation, the quantitative calculation indicated that the maximum relative errors between the simulated EMG MAV and the expected values were 17% (fuzzy controller), 110% (PID control), 66% (immune feedback control); furthermore, the corresponding values of the LFP PV were 12% (fuzzy controller), 53% (PID control), 55% (immune feedback control). The average relative errors of fuzzy controller, PID control, immune feedback control were 4.97%, 13.15%, 11.52%, in the EMG closed-loop experiment and 7.76%, 11.84%, 13.56%, in the LFP closed-loop experiment.Significance. The simulation and experimental results demonstrate that the closed-loop TUS with a fuzzy controller can realize the tracking control of the motor response and neural activity of mice.


Assuntos
Lógica Fuzzy , Redes Neurais de Computação , Animais , Simulação por Computador , Retroalimentação , Camundongos
5.
Front Plant Sci ; 13: 1087899, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618658

RESUMO

The medicinal plants were wildly library of natural products in drug discovery. The most active molecules with seven-membered rings skeleton represent a challenge for construction. A stereoselectivity (4 + 3) cycloadditions between allenyl ethers and substituted furans induced by chiral auxiliaries has been investigated. And the results showed significant stereoselectivities and regioselectivities. The optical cycloadducts with an oxygen-substituted seven-membered ring framework were generated by removing chiral auxiliaries under acidic conditions. The antiproliferative activity of the novel compounds displayed moderate antiproliferative effects toward T47D cells.

6.
Zool Res ; 40(3): 205-210, 2019 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31011131

RESUMO

Protease inhibitors have been reported rarely from the leech Hirudinaria manillensis. In this study, we purified a novel protease inhibitor (bdellin-HM-2) with anticoagulant properties from H. manillensis. With a molecular weight of 1.4x104, bdellin-HM-2 was also characterized with three intra-molecular disulfide bridges at the N-terminus and multiple HHXDD and HXDD motifs at the C-terminus. cDNA cloning revealed that the putative nucleotide-encoding protein of bdellin-HM-2 contained 132 amino acids and was encoded by a 399 bp open reading frame (ORF). Sequence alignment showed that bdellin-HM-2 shared similarity with the "non-classical" Kazal-type serine protease inhibitors, but had no inhibitory effect on trypsin, elastase, chymotrypsin, kallikrein, factor XIIa (FXIIa), factor XIa (FXIa), factor Xa (FXa), thrombin, or plasmin. Bdellin-HM-2 showed anticoagulant effects by prolonging the activated partial thromboplastin time (aPTT), indicating a role in enabling H. manillensis to obtain a blood meal from its host. Our results suggest that bdellin-HM-2 may play a crucial role in blood-sucking in this leech species and may be a potential candidate for the development of clinical anti-thrombotic drugs.


Assuntos
Anticoagulantes/metabolismo , Sanguessugas/metabolismo , Sequência de Aminoácidos , Animais , Anticoagulantes/química , Sequência de Bases , DNA Complementar , Tempo de Tromboplastina Parcial , Tempo de Protrombina
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-694586

RESUMO

Objective To study antioxidant role and mechanism of Rg1 in rats with cerebral ischemia reperfusion injury (IRI).Methods One hundred and twenty healthy male rats were randomly divided into six groups: control group, sham operation group, model group, different concentration (30,60,90 mg/kg) of Rg1 treatment group.MCAO SD rats model was established by suture-occluded method;the Rg1 treatment groups were given Rg1 i.p. in advance, after 24 hours of reperfusion, neurobehavioral scores of all groups were examined by Longa’s standard;The expression of Nrf2 and HO-1 were analyzed by western blot;The content of SOD and MDA was detected by kit.Results The score of model group rats are significantly higher than control group,compared with the model group, the score of different concentration of Rg1 treatment group was decreased (P<0.05) . The Nrf2 and HO-1 expression in model group was mildly higher than the control or sham group (P<0.05) . Both of them in every Rg1 treatment group was higher than model group. Compared with control or sham group, SOD content was observably depressed but MDA content was dramatically increased in model group,interestingly,SOD content was enhanced, MDA content was attenuated in different concentration of Rg1 treatment group (P<0.05). Conclusion Rg1 increases Nrf2 and HO-1 protein expression and SOD content, reduces MDA content,improves neurofunctional performance of rats after MCAO,and alleviates cerebral cerebral IRI.

9.
Pharmacogn Mag ; 11(42): 417-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25829784

RESUMO

BACKGROUND: Yin-Chen-Hao-Tang (YCHT) consists of three aqueous extracts from Artemisia capillaris, Gardenia sp., and prepared Rheum rhabarbarum (rhubarb) (3:2:1). YCHT is characterized by its anti-inflammatory properties in liver regulation and relief of jaundice. We aimed to study the effects and mechanisms of action of YCHT on biliary obstructive cirrhosis. MATERIALS AND METHODS: Secondary biliary fibrosis was induced in rats by bile duct ligation (BDL) and scission. One week after BDL, rats were randomly divided into a saline-treated BDL or YCHT-treated BDL group for 4 weeks. Liver function and hepatic hydroxyproline (Hyp) content were assessed. Types I and IV collagen (Col-IV), laminin, fibronectin, alpha smooth muscle actin (α-SMA), and proliferating cell nuclear antigen protein and messenger ribonucleic acid (mRNA) expression were assessed with immunohistochemistry and real-time polymerase chain reaction. RESULTS: In the YCHT-treated BDL group, serum total bilirubin, total bile acids, aspartate aminotransferase, alanine aminotransferase, and γ-glutamyl transferase were lower than those in the sham-operated BDL group. The proliferation of bile ducts in hepatic tissues and the Hyp content and Col deposition were also significantly lower than those in control rats. In addition, α-SMA and Col-IV staining was less obvious, and mRNA expression of Procol-α1 (IV), platelet derived growth factor subunit B (PDGF)-B, connective tissue growth factor, and transforming growth factor-beta in proliferative biliary epithelial cells (BECs) in the YCHT-treated BDL group was significantly lower than those in controls. CONCLUSIONS: YCHT effectively reduces the formation of biliary obstructive cirrhosis mainly via inhibition of BEC proliferation by down-regulation of PDGF-B mRNA expression, inhibition of BEC profibrogenic paracrines, and the epithelial-mesenchymal transition pathological process.

10.
Huan Jing Ke Xue ; 35(2): 475-80, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24812936

RESUMO

Rainwater samples were collected in the summer on "Shiyan 3" during the 2012 South China Sea Sectional Scientific Survey. The concentrations of anion and cation, and pH in precipitation were determined and backward trajectories of air mass were simulated to analyze the chemical characteristics of ions and examine the source of ions. The results indicated that the mean pH value of precipitation was 6.3, with 5.6 of minimal value in summer in South China Sea. The order of anion and cation abundance was Cl(-) > S04(2-) > NO3(-) and Na(+) > Mg(2+) > Ca(2+) > K(+). Cl(-) was the major anion and Na(+) was the major cation, with concentrations of 2 637.5 microeq x L(-1) and 2095.5 microeq x L(-1), respectively, showing that they were the characteristics of marine atmospheric precipitation. There was a good linear relationship between each pair of 7 ions, with correlation coefficient above 0.9, suggesting that they may have a common source. However, the correlation coefficients were lower between NO3(-) and other ions than the others, suggesting that NO3(-) had more complex sources. The concentrations of Ca(2+) and K(+) in precipitation may be related to coral environment in South China Sea. The backward trajectories in 6 stations showed that the air mass was from south and southwest of South China Sea, without passing through above the continent. These results suggested that precipitation affected by human ion source can be ignored in summer in South China Sea.


Assuntos
Monitoramento Ambiental , Chuva/química , Ânions/análise , Cátions/análise , China , Concentração de Íons de Hidrogênio , Oceanos e Mares , Estações do Ano
11.
World J Gastroenterol ; 20(1): 310-8, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24415887

RESUMO

AIM: To assess the efficacy and safety of combination therapy based on S-1, a novel oral fluoropyrimidine, vs S-1 monotherapy in advanced gastric cancer (AGC). METHODS: We searched PubMed, EMBASE and the Cochrane Library for eligible studies published before March 2013. Our analysis identified four randomized controlled trials involving 790 participants with AGC. The outcome measures were overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and grade 3-4 adverse events. RESULTS: Meta-analysis showed that S-1-based combination therapy significantly improved OS (HR = 0.77, 95%CI: 0.66-0.91, P = 0.002), PFS (HR = 0.58, 95%CI: 0.46-0.72, P = 0.000) and ORR (OR = 2.23, 95%CI: 1.54-3.21, P = 0.000). Sensitivity analysis further confirmed this association. Lower incidence of grade 3-4 leucopenia (OR = 4.06, 95%CI: 2.11-7.81), neutropenia (OR = 3.94, 95%CI: 2.1-7.81) and diarrhea (OR = 2.41, 95%CI: 1.31-4.44) was observed in patients with S-1 monotherapy. CONCLUSION: S-1-based combination therapy is superior to S-1 monotherapy in terms of OS, PFS and ORR. S-1 monotherapy is associated with less toxicity.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ácido Oxônico/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Tegafur/uso terapêutico , Antimetabólitos Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Progressão da Doença , Intervalo Livre de Doença , Combinação de Medicamentos , Humanos , Razão de Chances , Ácido Oxônico/efeitos adversos , Fatores de Risco , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Tegafur/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
12.
Singapore Med J ; 55(12): 644-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25630318

RESUMO

INTRODUCTION: The use of an additional biopsy from the gastric body may help improve the detection of Helicobacter pylori during endoscopy. This study aimed to determine whether such an additional biopsy is necessary in routine rapid urease test (RUT), and whether acid suppression and antibiotic therapy affect RUT results. METHODS: Patients recruited had two gastric mucosal biopsies taken - one from the gastric antrum and the other from the gastric body. Each biopsy was placed into separate RUT kits. Information on previous or current use of proton-pump inhibitors, H2 receptor antagonist, bismuth and antibiotics was obtained. Patients on any of those drugs one week prior to endoscopy were considered to have a positive drug history (PDH). RESULTS: Of the 400 patients recruited, 311 had negative RUTs and 89 had at least one positive RUT. Between the PDH and negative drug history (NDH) groups, there was a significant difference in the distribution of the location of the biopsies that yielded positive RUTs (p = 0.023). The NDH group had a higher proportion of patients who had positive RUTs for both locations, whereas the PDH group had a higher proportion of patients who had positive RUTs for only one location. CONCLUSION: As RUT results are significantly affected by the use of acid suppression and antibiotic therapies, biopsies for RUT should be taken from both the gastric antrum and body to minimise false negative results.


Assuntos
Antiácidos/farmacologia , Antibacterianos/farmacologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/isolamento & purificação , Urease/análise , Adulto , Idoso , Endoscopia , Endoscopia Gastrointestinal , Feminino , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastroenteropatias/diagnóstico , Gastroenteropatias/epidemiologia , Gastroenteropatias/microbiologia , História Antiga , Humanos , Pessoa de Meia-Idade , Singapura/epidemiologia
13.
Eur Spine J ; 22(1): 116-22, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22922801

RESUMO

PURPOSE: Few studies have investigated the role of hybrid surgery (HS) that incorporates anterior cervical discectomy and fusion (ACDF) and artificial disc replacement (ADR) techniques. To our knowledge, this is the first study that provides a direct comparison of all three groups in terms of intra-operative parameters and outcomes with a minimum follow-up of 2 years. METHODS: Seven consecutive patients who underwent HS were matched with another seven patients who underwent ACDF and ADR based on levels of surgery. Prospective data on demographics, pre-operative and post-operative assessments, complications and functional scores (VAS, NDI, EQ-5D health score and index) were analysed using Mann-Whitney U test. Type I error was set at 5 %. RESULTS: Duration of surgery was significantly shorter for ACDF at 135 min (p = 0.025) compared with HS and ADR. ACDF also had greater blood loss when compared with ADR (p < 0.036). ADR has the shortest duration of hospitalization followed by HS and ACDF (p < 0.031). The HS group returned to work fastest (54 days) when compared with both ACDF (107 days) and ADR (73 days) with statistical significance seen between HS and ACDF (p = 0.035). Cervical range of motion (ROM) and functional scores did not show any significant differences. CONCLUSION: HS is comparable to ACDF and ADR in terms of safety and feasibility. Findings of shorter in-hospital stay and earlier return to work in HS group may be further explored in large, randomised controlled trials.


Assuntos
Vértebras Cervicais/cirurgia , Discotomia/métodos , Fusão Vertebral/métodos , Substituição Total de Disco/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Amplitude de Movimento Articular , Recuperação de Função Fisiológica
14.
BMC Complement Altern Med ; 12: 33, 2012 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-22471627

RESUMO

BACKGROUND: Huangqi decoction was first described in Prescriptions of the Bureau of Taiping People's Welfare Pharmacy in Song Dynasty (AD 1078), and it is an effective recipe that is usually used to treat consumptive disease, anorexia, and chronic liver diseases. Transforming growth factor beta 1 (TGFß1) plays a key role in the progression of liver fibrosis, and Huangqi decoction and its ingredients (IHQD) markedly ameliorated hepatic fibrotic lesions induced by ligation of the common bile duct (BDL). However, the mechanism of IHQD on hepatic fibrotic lesions is not yet clear. The purpose of the present study is to elucidate the roles of TGFß1 activation, Smad-signaling pathway, and extracellular signal-regulated kinase (ERK) in the pathogenesis of biliary fibrosis progression and the antifibrotic mechanism of IHQD. METHODS: A liver fibrosis model was induced by ligation of the common bile duct (BDL) in rats. Sham-operation was performed in control rats. The BDL rats were randomly divided into two groups: the BDL group and the IHQD group. IHQD was administrated intragastrically for 4 weeks. At the end of the fifth week after BDL, animals were sacrificed for sampling of blood serum and liver tissue. The effect of IHQD on the TGFß1 signaling pathway was evaluated by western blotting and laser confocal microscopy. RESULTS: Decreased content of hepatic hydroxyproline and improved liver function and histopathology were observed in IHQD rats. Hepatocytes, cholangiocytes, and myofibroblasts in the cholestatic liver injury released TGFß1, and activated TGFß1 receptors can accelerate liver fibrosis. IHQD markedly inhibited the protein expression of TGFß1, TGFß1 receptors, Smad3, and p-ERK1/2 expression with no change of Smad7 expression. CONCLUSION: IHQD exert significant therapeutic effects on BDL-induced fibrosis in rats through inhibition of the activation of TGFß1-Smad3 and TGFß1-ERK1/2 signaling pathways.


Assuntos
Doenças Biliares/tratamento farmacológico , Ducto Colédoco/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Hepatopatias/tratamento farmacológico , Fígado/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Astrágalo , Astragalus propinquus , Doenças Biliares/metabolismo , Doenças Biliares/patologia , Ducto Colédoco/metabolismo , Ducto Colédoco/patologia , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibrose/tratamento farmacológico , Ligadura , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Fitoterapia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(9): 2413-6, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-21105408

RESUMO

The optical characteristics of chromophoric dissolved organic matter (CDOM) were determined in rain samples collected in Xiamen Island, during a rainy season in 2007, using fluorescence excitation-emission matrix spectroscopy associated with UV-Vis absorbance spectra. Results showed that the absorbance spectra of CDOM in rain samples decreased exponentially with wavelength. The absorbance coefficient at 300 nm [a(300)] ranged from 0.27 to 3.45 m(-1), which would be used as an index of CDOM abundance, and the mean value was 1.08 m(-1). The content of earlier stage of precipitation events was higher than that of later stage of precipitation events, which implied that anthropogenic sources or atmospheric pollution or air mass types were important contributors to CDOM levels in precipitation. EEMs spectra showed 4 types of fluorescence signals (2 humic-like fluorescence peaks and 2 protein-like fluorescence peaks) in rainwater samples, and there were significant positive correlations of peak A with C and peak B with S, showing their same sources or some relationship of the two humic-like substance and the two protein-like substance. The strong positive correlations of the two humic-like fluorescence peaks with a(300), suggested that the chromophores responsible for absorbance might be the same as fluorophores responsible for fluorescence. Results showed that the presence of highly absorbing and fluorescing CDOM in rainwater is of significant importance in atmospheric chemistry and might play a previously unrecognized role in the wavelength dependent spectral attenuation of solar radiation by atmospheric waters.

16.
Ying Yong Sheng Tai Xue Bao ; 19(4): 853-8, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18593049

RESUMO

Based on Miami model, this paper calculated the human appropriation of net primary production (HANPP) in the middle reach of Heihe River basin, discussed the relations between the HANPP and ecosystem diversity, and compared the values of HANPP and ecological footprint (EF) in sustainability assessment. The results showed that the increase of HANPP decreased the ecosystem diversity, and the current average HANPP in study area was 38.61%. The HANPP in Suzhou and Ganzhou districts already exceeded the potential maximum productivity. Considering the climate change and the development of social-economics, the ecosystems in study area would face more stress in the coming 40 years. Comparing with EF, HANPP was more available for the assessment of sustainability in the sight of ecosystem function change.


Assuntos
Agricultura/estatística & dados numéricos , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , Atividades Humanas/estatística & dados numéricos , China , Monitoramento Ambiental/métodos , Humanos , Rios
17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-296721

RESUMO

<p><b>OBJECTIVE</b>To evaluate the efficiency of micro-implant anchorage (MIA) for posterior teeth intruded and the result of the treatment of scissors bite on one-side posterior teeth.</p><p><b>METHODS</b>The study included 3 females and 1 male. All the overextruding upper posterior teeth were intruded by the MIA. The micro-implant screws were inserted into the buccal and lingual alveolar hone of the maxillary posterior teeth or the buccal alveolar hone of mandibular posterior teeth. About 0.833 N force was used to intrude the overgrowthing upper posterior teeth, and about 0.559 N force was used to draw buecally the low posterior teeth tilting lingually.</p><p><b>RESULTS</b>The overextruding upper posterior teeth were intruded 2.0 mm on average, the low posterior teeth tilting lingually were upreared buccally. All the MIA screws kept stable during the treatment, but there was a slight inflammation around the implant screws.</p><p><b>CONCLUSION</b>MIA could be used as an efficient method to correct scissors bite on one-side posterior teeth with intruding overgrowth upper posterior teeth, or uprearing buccally the tilting low posterior teeth.</p>


Assuntos
Feminino , Humanos , Masculino , Parafusos Ósseos , Oclusão Dentária , Dente Molar , Mordida Aberta , Procedimentos de Ancoragem Ortodôntica , Técnicas de Movimentação Dentária
18.
Huan Jing Ke Xue ; 28(8): 1788-95, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17926412

RESUMO

Mussels have been proposed as appropriate biomonitors of marine pollution, especially for monitoring metallic pollution based on variations of metallothionein as biomarkers. Under 2 exposure levels (12.7 microg/L, 63.5 microg/L), Cu accumulation and metallothionein-like protein (MTLP) induction by mussel (Perna viridis) digestive glands were investigated and simulated into dynamic models in the present work, and the soluble and total Cu burden of digestive glands were also determined. Calculated mean Cu uptake rates by mussel target organ were 2.045 and 7.028 microg x (g x d)(-1) respectively, and the theoretical equilibrium kinetic BCFs of Cu were 2074 and 1619 correspondingly. And within the exposure duration, different changing trends of ratio of soluble Cu to total Cu in digestive glands were observed in the two groups. The MTLP level of control samples was (0.551 +/- 0.037) mg/g, and the counterparts are 0.407 - 0.699 mg/g, 0.826 - 0.942 mg/g respectively when mussels were exposed to 12.7 microg/L and 63.5 microg/L Cu solutions. Statistically significant MTLP induction (p < 0.001) was observed under higher exposure level. MTLP contents in digestive glands increased with the exposure Cu concentration and body accumulation of metal. There is a significantly negative exponential rise relationship (p < 0.000 1) between MTLP and Cu concentrations accumulated in the digestive glands of mussels.


Assuntos
Bivalves/metabolismo , Cobre/farmacocinética , Metalotioneína/metabolismo , Poluentes Químicos da Água/farmacocinética , Animais , Bivalves/efeitos dos fármacos , Cobre/metabolismo , Cobre/toxicidade , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Exposição Ambiental/análise , Distribuição Tecidual , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 26(4): 344-7, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-16689005

RESUMO

OBJECTIVE: To investigate the recipe-based pathogenesis and effects of Xiayuxue Decoction (XD), Yinchenhao Decoction (YcD), Yiguanjian Decoction (YgD) and Huangqi Decoction (HD) on carbon tetrachloride (CCl4) induced liver cirrhosis formation in rats on the basis of the recognition of basic pathogenesis of liver cirrhosis in TCM and train of thoughts of detecting the TCM syndrome by recipe. METHODS: Model rats of liver cirrhosis were established by subcutaneous injecting of 100% CCl4 3ml/kg followed by 50% CCl4 olive solution 2ml/kg, twice a week for 12 weeks. They were randomly divided into the model group, the XD treated group, the YcD treated group, the YgD treated group and the HD treated group. Rats in the three treated group received the treatment starting from the 9th week of modeling with the corresponding decoctions. All animals were sacrificed by the end of the 12th week, and their hepatic function, liver pathological changes and hydroxyproline (Hyp) content of hepatic tissue were detected. RESULTS: (1) Typical chronic liver injury and fibrosis became evident in the model rat at the 8th week and cirrhosis came into being at the 12th week. (2) Compared with the rats in the model group, hepatic pathological changes were alleviated significantly, content of Hyp in hepatic tissue was decreased markedly and hepatic function improved remarkably in the XD group and YgD group. The improvement in the XD group was superior to that in the YgD group, while the serum albumin level elevated more significant in the YgD group. CONCLUSION: The main pathological changes during CCl4 induced liver cirrhosis formation in rats is the rapid hyperplasia of hepatic fibrous connective tissue and obstruction of collaterals by blood stasis, thus induced reconstruction of the tissue structure, which could be treated with XD effectively, while the severe injury of liver parenchyma in this phase is another pathological change of Gan-yin deficiency syndrome, which could be effectively treated with YgD by its Yin-nourishing action.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Cirrose Hepática Experimental/tratamento farmacológico , Animais , Tetracloreto de Carbono , Diagnóstico Diferencial , Hidroxiprolina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/diagnóstico , Masculino , Medicina Tradicional Chinesa , Fitoterapia , Distribuição Aleatória , Ratos , Ratos Wistar , Deficiência da Energia Yin/tratamento farmacológico
20.
Zhong Xi Yi Jie He Xue Bao ; 4(3): 281-4, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16696916

RESUMO

OBJECTIVE: To establish a model of alcoholic liver fibrosis (ALF) in rats induced by complex factors. METHODS: Forty-seven healthy male rats were divided into three groups: normal control group (n=12), minor CCl4 group (n=12) and complex factors group (n=27). The rats in the complex factors group were fed a complex diet including alcohol, corn oil and pyrazole, and administered with intraperitoneal injection of minor CCl4 to induce ALF. During induction process, the histopathological changes of liver tissue and the values of liver-to-body weight ratio were both observed regularly. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (gamma-GT) in these three groups were all examined at the 12th week of the induction process. RESULTS: At the 12th week of the induction process, the model of ALF induced by complex factors was successfully established in rats, and the histopathological presentations showed alcoholic fatty liver, hepatitis and liver fibrosis in a sequence along with the induction process. The value of liver-to-body weight ratio and the serum levels of ALT, AST and gamma-GT of rats in the complex factors group were all significantly different from those in the other two groups. CONCLUSION: It is a steady and effective way to induce ALF in rats with complex diet and minor CCI4 injection.


Assuntos
Modelos Animais de Doenças , Etanol , Cirrose Hepática Experimental/induzido quimicamente , Animais , Intoxicação por Tetracloreto de Carbono , Masculino , Ratos , Ratos Wistar
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