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1.
Ecotoxicol Environ Saf ; 277: 116363, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663190

RESUMO

Environmental aflatoxin B1 (AFB1) exposure has been proposed to contribute to hepatocellular carcinoma by promoting liver fibrosis, but the potential mechanisms remain to be further elucidated. Extracellular vesicles (EVs) were recognized as crucial traffickers for hepatic intercellular communication and play a vital role in the pathological process of liver fibrosis. The AFB1-exposed hepatocyte-derived EVs (AFB1-EVs) were extracted, and the functional effects of AFB1-EVs on the activation of hepatic stellate cells (HSCs) were explored to investigate the molecular mechanism of AFB1 exposure-induced liver fibrogenesis. Our results revealed that an environment-level AFB1 exposure induced liver fibrosis via HSCs activation in mice, while the AFB1-EVs mediated hepatotoxicity and liver fibrogenesis in vitro and in vivo. AFB1 exposure in vitro increased PINK1/Parkin-dependent mitophagy in hepatocytes, where upregulated transcription of the PARK2 gene via p53 nuclear translocation and mitochondrial recruitment of Parkin, and promoted AFB1-EVs-mediated mitochondria-trafficking communication between hepatocytes and HSCs. The knockdown of Parkin in HepaRG cells reversed HSCs activation by blocking the mitophagy-related AFB1-EVs trafficking. This study further revealed that the hepatic fibrogenesis of AFB1 exposure was rescued by genetic intervention with siPARK2 or p53's Pifithrin-α (PFTα) inhibitors. Furthermore, AFB1-EVs-induced HSCs activation was relieved by GW4869 pharmaceutic inhibition of EVs secretion. These results revealed a novel mechanism that AFB1 exposure-induced p53-Parkin signal axis regulated mitophagy-dependent hepatocyte-derived EVs to mediate the mitochondria-trafficking intercellular communication between hepatocytes and HSCs in the local hepatotoxic microenvironment to promote the activated HSCs-associated liver fibrogenesis. Our study provided insight into p53-Parkin-dependent pathway regulation and promised an advanced strategy targeting intervention to EVs-mediated mitochondria trafficking for preventing xenobiotics-induced liver fibrosis.


Assuntos
Aflatoxina B1 , Vesículas Extracelulares , Células Estreladas do Fígado , Hepatócitos , Cirrose Hepática , Mitofagia , Proteína Supressora de Tumor p53 , Ubiquitina-Proteína Ligases , Aflatoxina B1/toxicidade , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Vesículas Extracelulares/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Mitofagia/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Animais , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Camundongos , Masculino , Humanos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos
2.
Front Plant Sci ; 14: 1240028, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38078087

RESUMO

Introduction: Tilia miqueliana is an endemic species whose population is declining. The permeability barrier and mechanical constraint of the pericarp (seed coat) are important causes of its seed dormancy. Although there has been considerable research on this subject, questions remain regarding how the permeability barrier and mechanical constraint of the seed coat are eliminated during dormancy release and how water enters the seed. Therefore, protecting the species by improving its germination/dormancy breaking in the laboratory is urgent. Methods: In this study, the changes in the cellular structure, mechanical properties, and components of the Tilia miqueliana seed coat after an H2SO4-gibberellic acid (GA3) treatment were analyzed during dormancy release. Various analyses (e.g., magnetic resonance imaging, scanning electron microscopy, and paraffin section detection) revealed the water gap and water channel. Results: The H2SO4 treatment eliminated the blockage at the micropyle and hilum of the seeds. Water entered the seeds through the water gap (micropyle) rather than through the hilum or seed coat, after which it dispersed along the radicle, hypocotyl, and cotyledon to the endosperm. During the cold stratification period, the cellular structure was damaged and an increasing number of holes appeared on the inner and outer surfaces of the seed coat. Vickers hardness tests showed that GA3 decreased the seed coat hardness. Additionally, the seed coat lignin and total phenol contents continuously decreased during the cold stratification period. Notably, the Liquid chromatography-mass spectrometry (LC-MS) analysis of the seed coat detected polyethylene glycol (osmoregulator), which may have destabilized the water potential balance inside and outside the seed and increased the water content to levels required for germination, ultimately accelerating seed dormancy release. Discussion: This sophisticated and multi-level study reveals how H2SO4 and GA3 eliminate the permeability barrier and mechanical constraints of the seed coat during dormancy release of Tilia miqueliana seeds. This will be beneficial to artificially assist the natural regeneration and population expansion of Tilia miqueliana.

3.
Front Plant Sci ; 14: 1228069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692432

RESUMO

Introduction: Cryo treatment of dry seeds is known to attenuate the structure of fruit and seed coats, but little is known about the microstructural impacts of such treatment. The seeds of Tilia miqueliana are dispersed within a hard pericarp, the manual removal (hulling) of which is time-consuming and inefficient. Rapid hulling technology is urgently needed for sustainable production and convenience of edible nuts. Methods: We explored the mechanistic basis of liquid nitrogen (N)-treatment weakening of the pericarp of T. miqueliana fruits using a range of microscopical, biophysical and chemical approaches. Results: Liquid N treatment (40 s) resulted in lower pericarp contents of cellulose and hemicellulose, and increased amounts of lignin. Profound changes in cell structure and mechanical properties included the emergence of large holes and gaps between the mesocarp and endocarp cells. Also, the toughness of the pericarp decreased, whilst the hardness and brittleness increased, thereby changing the fracture type from ductile to brittle. Liquid N treatment of dry fruits followed by tapping with a hammer, reduced the number of damaged seeds three-fold and pericarp peeling time four-fold compared with manual hulling, whilst seed viability was not negatively affected. Discussion: Comparable findings for the efficient and economical removal of hard covering structures from dispersal units of five more species from three other families following liquid N treatment indicates the potential application of our findings to large-scale production of seeds and seedlings for breeding, forestry and conservation/restoration purposes. Furthermore, it introduces a novel concept for postharvest treatment and pre-treatment of deep processing in nuts.

4.
Theranostics ; 13(12): 4288-4302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554285

RESUMO

Rationale: As a key endogenous negative regulator of ferroptosis, glutathione peroxidase 4 (GPX4) can regulate its antioxidant function through multiple post-translational modification pathways. However, the effects of the phosphorylation/dephosphorylation status of GPX4 on the regulation of inducible ferroptosis in hepatocellular carcinoma (HCC) remain unclear. Methods: To investigate the effects and molecular mechanism of GPX4 phosphorylation/dephosphorylation modification on ferroptosis in HCC cells. Sorafenib (Sora) was used to establish the ferroptosis model in HCC cells in vitro. Using the site-directed mutagenesis method, we generated the mimic GPX4 phosphorylation or dephosphorylation HCC cell lines at specific serine sites of GPX4. The effects of GPX4 phosphorylation/dephosphorylation modification on ferroptosis in HCC cells were examined. The interrelationships among GPX4, p53, and protein phosphatase 2A-B55ß subunit (PP2A-B55ß) were also explored. To explore the synergistic anti-tumor effects of PP2A activation on Sora-administered HCC, we established PP2A-B55ß overexpression xenograft tumors in a nude mice model in vivo. Results: In the Sora-induced ferroptosis model of HCC in vitro, decreased levels of cytoplasmic and mitochondrial GPX4, mitochondrial dysfunction, and enhanced p53 retrograde signaling occurred under Sora treatment. Further, we found that mitochondrial p53 retrograded remarkably into the nucleus and aggravated Sora-induced ferroptosis. The phosphorylation status of GPX4 at the serine 2 site (GPX4Ser2) revealed that mitochondrial p-GPX4Ser2 dephosphorylation was positively associated with ferroptosis, and the mechanism might be related to mitochondrial p53 retrograding into the nucleus. In HCC cells overexpressing PP2A-B55ß, it was found that PP2A-B55ß directly interacted with mitochondrial GPX4 and promoted Sora-induced ferroptosis in HCC. Further, PP2A-B55ß reduced the interaction between mitochondrial GPX4 and p53, leading to mitochondrial p53 retrograding into the nucleus. Moreover, it was confirmed that PP2A-B55ß enhanced the ferroptosis-mediated tumor growth inhibition and mitochondrial p53 retrograde signaling in the Sora-treated HCC xenograft tumors. Conclusion: Our data uncovered that the PP2A-B55ß/p-GPX4Ser2/p53 axis was a novel regulatory pathway of Sora-induced ferroptosis. Mitochondrial p-GPX4Ser2 dephosphorylation triggered ferroptosis via inducing mitochondrial p53 retrograding into the nucleus, and PP2A-B55ß was an upstream signal modulator responsible for mitochondrial p-GPX4Ser2 dephosphorylation. Our findings might serve as a potential theranostic strategy to enhance the efficacy of Sora in HCC treatment through the targeted intervention of p-GPX4 dephosphorylation via PP2A-B55ß activation.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Proteína Fosfatase 2 , Sorafenibe , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Núcleo Celular , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Xenoenxertos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/patologia , Transplante de Neoplasias , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/química , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Sorafenibe/uso terapêutico , Proteína Fosfatase 2/metabolismo
5.
Int Wound J ; 20(8): 3057-3072, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37312275

RESUMO

Adequate blood supply, a prerequisite for flap survival after grafting, makes angiogenesis of the flap the biggest problem to be solved. Researches have been conducted around vascularisation in correlation with flap grafting. However, bibliometric analyses systematically examining this research field are lacking. As such, we herein sought to conduct comprehensive comparative analyses of the contributions of different researchers, institutions, and countries to this research space in an effort to identify trends and hotspots in angiogenesis and vascularisation in the context of flap grafting. Publications pertaining to angiogenesis and vascularisation in the context of flap grafting were retrieved from the Web of Science Core Collection. References were then analysed and plotted using Microsoft Excel 2019, VOSviewer, and CiteSpace V. In total, 2234 papers that were cited 40 048 times (17.63 citations/paper) were included in this analysis. The greatest number of studies were from the United States, with these studies exhibiting both the highest number of citations (13 577) and the greatest overall H-index (60). For The institutions that published the greatest number of studies were WENZHOU MEDICAL UNIVERSITY (681), while UNIVERSITY OF ERLANGEN NUREMBERG has the highest number of citations (1458), and SHANGHAI JIAO TONG UNIVERSITY holds the greatest overall H-index (20). The greatest number of studies in this research space were published by Gao WY, while Horch RE was the most commonly cited researcher in the field. The VOS viewer software clustered relevant keywords into three clusters, with clusters 1, 2, 3, and 4 corresponding to studies in which the keywords 'anatomy', 'survival', 'transplantation', 'therapy' most frequently appeared. The most promising research hotspot-related terms in this field included 'autophagy', 'oxidative stress', 'ischemia/reperfusion injury', which exhibited a most recent average appearing year (AAY) of 2017 and after. Generally speaking, the results of this analysis indicate that the number of articles exploring angiogenesis and flap-related research has risen steadily, with the United States and China being the two countries publishing the greatest proportion of studies in this field. The overall focus of these studies has shifted away from 'infratest and tissue engineering' towards 'mechanisms'. In the future, particular attention should be paid to emerging research hotspots, which include 'ischemia/reperfusion injury' and treatments for promoting vascularization, such as 'platelet-rich plasma'. In light of these findings, funding agencies should continue increasing their investment in the exploration of the concrete mechanisms and interventional therapeutic relevance of angiogenesis during flap transplantation.


Assuntos
Bibliometria , Traumatismo por Reperfusão , Humanos , China , Autofagia , Isquemia
6.
J Diabetes Res ; 2023: 3720602, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937538

RESUMO

This research is aimed at figuring out the potential circular RNA (circRNA)/long noncoding RNA- (lncRNA-) microRNA- (miRNA-) mRNA regulatory networks associated with a vascular injury in type 2 diabetes mellitus (T2DM). Differentially expressed genes (DEGs) screened in T2DM-related expression datasets were intersected with genes associated with vascular injury in T2DM to obtain candidate DEGs, followed by the construction of an interaction network of DEGs. The upstream miRNAs of candidate genes were predicted by mirDIP, miRWalk, and DIANA TOOLS databases, and the upstream lncRNAs/circRNAs of miRNAs by DIANA-LncBase/circBank database, followed by the construction of circRNA/lncRNA-miRNA-mRNA regulatory networks. Peripheral blood was attained from T2DM patients with macroangiopathy for clinical validation of expression and correlation of key factors. Differential analysis screened 37 candidate DEGs correlated with vascular injury in T2DM. Besides, MAPK3 was a core gene associated with vascular injury in T2DM. Among the predicted upstream miRNAs of MAPK3, miR-4270, miR-92a-2-5p, miR-423-5p, and miR-613 ranked at the top according to binding scores. The upstream lncRNAs and circRNAs of the 4 miRNAs were further predicted, obtaining 11 candidate lncRNAs and 3 candidate circRNAs. Moreover, KCNQ1OT1, circ_0020316, and MAPK3 were upregulated, but miR-92a-2-5p was downregulated in the peripheral blood of T2DM patients with macroangiopathy. Mechanistically, KCNQ1OT1 and circ_0020316 bound to miR-92a-2-5p that inversely targeted MAPK3. Collectively, KCNQ1OT1/circ_0020316-miR-92a-2-5p-MAPK3 coexpression regulatory networks might promote vascular injury in T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , MicroRNAs , RNA Longo não Codificante , Lesões do Sistema Vascular , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Redes Reguladoras de Genes , Análise em Microsséries
7.
Med Sci Monit ; 23: 5550-5557, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29162795

RESUMO

BACKGROUND Array CGH is the criterion standard for identifying copy number variations (CNV), but the restrictive requirement of DNA quality and relatively high cost prevent the use of this method as a general assay in hospitals in developing countries. Our principal objective was to determine whether the semiconductor sequencing platform (SSP) could be an alternative method in CNV detection for spontaneous miscarriage. MATERIAL AND METHODS A total of 443 spontaneous miscarriage samples were collected and subjected to low-coverage (0.1X) whole-genome analysis by SSP. These samples were verified by array CGH and 8 low-quality DNA samples were analyzed by SSP and validated by MLPA. RESULTS SSP detected 195 chromosomal numerical abnormalities, 74 CNVs, and 9 mosaicisms among the 435 samples. Among 74 CNV abnormalities, SSP detected an equal number (56) of CNVs 56 >1 Mb with array CGH. However, SSP missed more 6 cases CNVs <1 Mb than array CGH (12 vs. 18). SSP detected more mosaicisms than array CGH (9 vs. 7, p=0.5). Interestingly, SSP detected the mosaicism which had only 8% X monosomy, which was much lower than the minimal percentage of monosomy that was detected by array CGH. CONCLUSIONS SSP is of equivalent efficacy as array CGH in detecting CNVs >1 Mb, and performs better in identifying mosaicism. With the merits of low cost and less demand of input DNA, SSP is a good alternative for use in genetic diagnosis.


Assuntos
Aborto Espontâneo/genética , Hibridização Genômica Comparativa/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Aberrações Cromossômicas/embriologia , Cromossomos/genética , DNA/genética , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Gravidez , Sequenciamento Completo do Genoma/métodos
8.
Biotechnol Lett ; 39(10): 1529-1535, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28600648

RESUMO

OBJECTIVE: To produce a recombinant spermatozoa antigen peptide using the E. coli: PhoA system on a protein chip for screening anti-sperm antibodies (ASA). RESULTS: The purity of the recombinant spermatozoa antigen exceeded 95% after two-step purification, as assessed using SDS-PAGE and HPLC. The diagnostic performance of a protein chip coated with the recombinant antigen peptide was evaluated by examining ASA in 51 infertile patients in comparison with a commercial ELISA kit. The area under the receiver operating characteristic curve (AUC) was 0.944, which indicated that the protein chip coated with recombinant spermatozoa antigen peptide was consistent with ELISA for ASA detection. CONCLUSION: A recombinant spermatozoa antigen was expressed in the E. coli PhoA secretory expression system and its potential application for clinical ASA detection was validated.


Assuntos
Escherichia coli/metabolismo , Infertilidade Masculina/imunologia , Proteínas Recombinantes/metabolismo , Espermatozoides/imunologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Antígenos/genética , Antígenos/metabolismo , Área Sob a Curva , Autoanticorpos/análise , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Masculino , Análise Serial de Proteínas , Proteínas Recombinantes/genética
9.
Zhonghua Nan Ke Xue ; 21(10): 892-5, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26665676

RESUMO

OBJECTIVE: To investigate the efficacy and adverse effects of dapoxetine in the treatment of premature ejaculation. METHODS: We randomly assigned outpatients with premature ejaculation in the proportion of 2:1 to receive 30 mg dapoxetine on demand (n =78) or 50 mg sertraline qd for one month (n = 39). Follow-up was accomplished in 95 cases, 63 in the dapoxetine group and 32 in the sertraline group. We recorded the intravaginal ejaculatory latency time (IELT), clinical global impression of change (CGIC) score, and adverse reactions of the patients and compared them between the two groups. RESULTS: IELT was significantly increased in both the dapoxetine (from [0.87 ± 0.31] to [2.84 ± 0.68] min, P < 0.05) and the sertraline group (from [0.84 ± 0.28] to [2.71 ± 0.92] min, P < 0.05) after medication. Based on the CGIC scores in premature ejaculation, the rate of excellence or effectiveness was 36.5% in the dapoxetine and 37. 5% in the sertraline group, and the rate of improvement was 63.5% in the former and 71.9% in the latter. The incidence rates of dizziness, nausea, headache, and diarrhea were slightly higher (P > 0.05) while those of fatigue, somnolence, and dry mouth significantly higher (P < 0.05) in the sertraline than in the dapoxetine group. CONCLUSION: On-demand oral medication of dapoxetine is effective and well-tolerated for the treatment of premature ejaculation.


Assuntos
Benzilaminas/uso terapêutico , Naftalenos/uso terapêutico , Ejaculação Precoce/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Sertralina/administração & dosagem , Benzilaminas/efeitos adversos , Método Duplo-Cego , Ejaculação/efeitos dos fármacos , Ejaculação/fisiologia , Humanos , Masculino , Naftalenos/efeitos adversos , Pacientes Ambulatoriais , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Sertralina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
10.
Huan Jing Ke Xue ; 36(1): 56-63, 2015 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-25898647

RESUMO

Total suspended matter (TSM) plays an important role in determining the underwater light climate, which then affects the lake primary production. Therefore, TSM concentration is an important parameter for lake water quality and water environment assessment. This study developed an empirical estimation model and presented the spatial distribution of TSM concentration for the relatively clear Xin'anjiang Reservoir based on the in situ ground data and the matching Landsat 8 data. The results showed that Band 2, Band 3 and Band 8 of Landsat 8 data were the sensitive bands of TSM estimation in Xin'anjiang Reservoir with the linear determination coefficients of 0.37, 0.51 and 0.42, respectively. However, the linear models using Band 2, Band 3 and Band 8 could not give a reasonable and satisfying estimation accuracy. Therefore, a three-band combination estimation model of TSM concentration using Band 2, Band 3 and Band. 8 was calibrated and validated to improve the TSM concentration estimation accuracy. The determination coefficient, mean relative error and root mean square error were 0.92, 11% and 0.16 mg x L(-1), respectively for the three-band combination model. Overall, the TSM concentration was relatively low in Xin'anjiang Reservoir, ranging from 0. 04 to 24. 54 mg x L(-1) with a mean value of 2.19 mg x L(-1). Higher TSM concentrations were distributed in the nearshore zones and small bays such as Fengshuling bay, Fenkou bay, Weiping bay, Anyang bay, Dashu bay and Linqi bay, which were affected by input rivers rainfall and human dredging activity. Therefore, this study demonstrated that the combination of three bands using Landsat 8 data could be used to estimate the TSM concentration in the relatively clear Xin'anjiang Reservoir.


Assuntos
Monitoramento Ambiental , Água Doce/análise , Imagens de Satélites , Baías , China , Lagos , Luz , Modelos Teóricos
11.
Huan Jing Ke Xue ; 35(7): 2528-38, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25244834

RESUMO

Absorption characteristics of total suspended particulate, phytoplankton and tripton in Lake Qiandaohu are presented based on the in situ data collected in winter (from December 2012 to February 2013) and summer (from July to August 2013). The mean values of total suspended particle absorption coefficients at 440 nm [a(p) (440)] in winter and summer are (0.20 +/- 0.07) m(-1) and (0.24 +/- 0.17) m(-1). Correspondingly, the mean values of a(p) (675) are (0.07 +/- 0.02) m(-1) and (0.10 +/- 0.07) m(-1). In winter the absorption spectra of total suspended particulate matters can be divided into two cases: the absorption spectra are similar to those of phytoplankton in the northwest lake and to those of tripton in other lake regions. In summer, the absorption spectra of total suspended particles are similar to those of phytoplankton from 400 nm to 700 nm. The mean values of phytoplankton absorption coefficients at 440 nm [a(ph) (440)] are (0.10 +/- 0.03) m(-1) in winter, and (0.17 +/- 0.14) m(-1) in summer. Accordingly, the mean values of a(ph) (675) are (0.05 +/- 0.02) m(-1) and (0.08 +/- 0.07) m(-1). The mean values of Chlorophyll-specific absorption coefficients (by the concentration of Chla) at440 nm a(*)(ph)(440) are (0.045 +/- 0.010) m2 x mg(-1) in winter and (0.039 +/- 0.013) m2 x mg(-1) in summer. At the same time, the mean values of a(*)(ph) (675) are (0.022 +/- 0.004) m2 x mg(-1) and (0.019 +/- 0.005) m2 x mg(-1). Significantly linear correlations are found between phytoplankton absorption coefficients and chlorophyll a concentration, trophic level index (TLI). Chlorophyll-specific absorption coefficients vary with the chlorophyll a concentrations following a power function. The tripton absorption coefficients exponentially decrease from 400 nm to 700 nm. The correlation between tripton absorption coefficients and inorganic particles is significant in winter, whereas, the correlation between tripton absorption coefficients and the concentrations of total suspended particles and organic particles are significant in summer.


Assuntos
Monitoramento Ambiental , Lagos/química , Material Particulado/análise , Estações do Ano , China , Clorofila/análise , Clorofila A , Fitoplâncton
12.
Huan Jing Ke Xue ; 34(2): 517-24, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23668117

RESUMO

Based on the underwater irradiance profile measurement and water samples collection in September, October 2007 in Lake Donghu, Lake Liangzi and Lake Honghu, and in April in 2010 in Lake Kuileihu, the diffuse attenuation coefficient and the dominant attenuation factors were analyzed. The ranges of diffuse attenuation coefficient and total suspended solid (TSS), organic suspended solid (OSS), inorganic suspended solid (ISS), chlorophyll a (Chla), and dissolved organic carbon (DOC) concentration varied less in Lake Donghu and Lake Kuileihu than in Lake liangzi and Lake Honghu. The regression analysis showed that ISS was the dominant affecting factor of transparency in Lake Donghu and Lake Kuileihu, but ISS and OSS jointly controlled the transparency in Lake Liangzi and Lake Honghu. The diffuse attenuation coefficient minimum occurred near 580 nm. At around 675 nm, the diffuse attenuation coefficient peak was due to phytoplankton absorption, especially at sites with high pigment concentration. The euphotic depth was less than the mean water depth in Lake Donghu, suggesting that the submerged aquatic vegetation (SAV) can not grow in the present underwater light climate. However, the euphotic depth was larger than the mean water depth in other three lakes showing that the underwater light climate can meet the light requirements for the growth of SAV. The regression analysis showed that ISS was the dominant affecting factor of PAR attenuation in Lake Donghu and Lake Kuileihu, but ISS, OSS and Chla jointly controlled PAR attenuation in lake Liangzi and lake Honghu. The significant correlation between the beam attenuatin coefficient at 750 nm and PAR difffuse attenuation coefficient showed that the particles scattering significantly contributed to underwater irradiance attenuation.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Água Doce , Espalhamento de Radiação , Poluentes da Água/análise , China , Clorofila/análise , Clorofila A , Eucariotos/crescimento & desenvolvimento , Eucariotos/metabolismo , Lagos , Nefelometria e Turbidimetria , Tamanho da Partícula , Rios
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(12): 3286-92, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24611388

RESUMO

Little is known about DOM characteristics in medium to large sized lakes located in the middle and lower reaches of Yangtze River, like Lake Honghu, Lake Donghu and Lake Liangzihu. Absorption, fluorescence and composition characteristics of chromophoric dissolved organic matter (CDOM) are presented using the absorption spectroscopy, the excitation-emission ma trices (EEMs) fluorescence and parallel factor analysis (PARAFAC) model based on the data collected in Sep-Oct. 2007 including 15, 9 and 10 samplings in Lake Honghu, Lake Donghu and Lake Liangzihu, respectively. CDOM absorption coefficient at 350 nm a(350) coefficient in Lake Honghu was significantly higher than those in Lake Donghu and Lake Liangzihu (t-test, p< 0. 001). A significant negative correlation was found between CDOM spectral slope in the wavelength range of 280-500 nm (S280-500) and a(350) (R2 =0. 781, p<0. 001). The mean value of S280-500 in Lake Honghu was significantly lower than those in Lake Donghu (t-test, p

14.
J Urol ; 187(4): 1336-40, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22342512

RESUMO

PURPOSE: Although holmium laser enucleation of the prostate has been proven to be an excellent technique for the treatment of benign prostatic hyperplasia, it has not been widely applied due to technical difficulties and longer operative time. We modified the current technique of enucleation and present our initial experience. MATERIALS AND METHODS: A total of 189 patients with benign prostatic hyperplasia underwent prostatectomy with our modified technique for holmium laser enucleation of the prostate. Intraoperative and postoperative data were prospectively collected. For followup International Prostate Symptom Score, quality of life, maximal flow rate and post-void residual urine were recorded. RESULTS: Mean±SD preoperative prostate volume was 78.1±24.3 cc and 60.9±39.2 gm tissue were enucleated. Mean operative and enucleation times were 54.7±21.1 and 36.5±16.3 minutes, respectively. Mean serum hemoglobin decrease was 0.98±0.72 gm/dl. Mean catheter time was 1.2±0.5 days and mean postoperative hospital stay was 4.9±3.4 days. Serious complications were not observed. Three patients complained of transient stress incontinence which resolved within 3 months. Significant improvement occurred in International Prostate Symptom Score, quality of life, maximal flow rate and post-void residual urine volume at 3 and 6-month followup compared with the preoperative baseline. CONCLUSIONS: The modified holmium laser enucleation of the prostate technique is effective and safe when treating benign prostatic hyperplasia.


Assuntos
Lasers de Estado Sólido/uso terapêutico , Próstata/cirurgia , Prostatectomia/métodos , Hiperplasia Prostática/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
15.
Zhonghua Nan Ke Xue ; 11(4): 275-7, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15921258

RESUMO

OBJECTIVE: To investigate the etiology and treatment of bladder spasm associated with benign prostatic hyperplasia (BPH). METHODS: Urodynamic tests were performed in 102 cases of BPH before operation. The correlation of bladder spasm with aging, international prostate symptom score (IPSS), quality of life, prostatic volume, operation methods and urodynamic indexes was studied by t and chi2 tests. RESULTS: The incidences of bladder spasm in the lower compliant bladder and unstable bladder were 32.1% (9/28) and 42.5% (13/20), and those after suprapubic prostatectomy and transurethral resection of the prostate (TURP) were 50.9% (26/51) and 23.3% (12/51). There was significant difference between operation methods (P < 0.05). CONCLUSION: Bladder spasm easily develops in the lower compliant bladder and unstable bladder, especially after suprapubic prostatectomy. TURP might decrease the incidence of bladder spasm after BPH operation.


Assuntos
Complicações Pós-Operatórias , Hiperplasia Prostática/cirurgia , Espasmo/etiologia , Doenças da Bexiga Urinária/etiologia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Espasmo/prevenção & controle , Ressecção Transuretral da Próstata , Doenças da Bexiga Urinária/prevenção & controle , Urodinâmica
16.
Zhonghua Yi Xue Za Zhi ; 83(19): 1665-7, 2003 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-14642099

RESUMO

OBJECTIVE: To evaluate the age-specific reference ranges for serum prostate-specific antigen in Chinese men. METHODS: Serum tPSA and fPSA were measured by enzyme-linked immunosorbent assay (ELISA) and fPSA/tPSA ratio was calculated in 1,096 health Chinese men of 23 - 85 years old. The relationship between age and PSA indexes was analyzed with simple linear regression. RESULTS: The recommended age-specific reference range (95th percentile) for serum PSA for Chinese were: 1.20 microg/L for 20-29 years; 1.21microg/L for 30-39 years; 1.23 microg/L for 40-49 years; 2.35 microg/L for 50-59 years; 3.20 microg/L for 60-69 years; 3.39 microg/L for >or= 70 years. The serum PSA concentration correlated directly with age. The age-specific reference range was lower for Chinese men than not only for white and black men, but also for Japanese and Koreans men. CONCLUSION: The age-specific reference ranges for serum PSA are lower significantly for Chinese men than for black, white men, even for Japanese and Koreans men. Study the normal upper limit of PSA and the age-specific reference ranges for serum prostate-specific antigen in Chinese men is very important.


Assuntos
Antígeno Prostático Específico/sangue , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , População Negra , China/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , População Branca
17.
Zhonghua Nan Ke Xue ; 9(6): 451-3, 2003 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-14574813

RESUMO

OBJECTIVE: To investigate the prevalence of chronic prostatitis in men with premature ejaculation. METHODS: The segmented urine specimens before and after prostatic massage and the expressed prostatic secretion specimens from 106 patients with premature ejaculation and 38 controls were evaluated by microscopic and/or bacteriological studies. The prevalence of premature ejaculation was also investigated in 120 patients with chronic prostatitis. RESULTS: Prostatic inflammation was found in 46.2% and chronic bacterial prostatitis in 34.7% of the subjects with premature ejaculation, respectively. Compared with the controls, the findings were statistically significant (P < 0.05). The prevalence of premature ejaculation in the patients with chronic prostatitis was 47.5% (57/120). CONCLUSIONS: Chronic prostatic inflammation may play a role in the pathogenesis of some cases of premature ejaculation and it is important to give a careful examination of the prostate before initiating any therapy for premature ejaculation.


Assuntos
Ejaculação , Prostatite/complicações , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Psicogênicas/etiologia , Adulto , Doença Crônica , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Próstata/diagnóstico por imagem , Prostatite/epidemiologia , Ultrassonografia
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