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1.
Huan Jing Ke Xue ; 45(8): 4656-4669, 2024 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-39168685

RESUMEN

It is of great significance to explore the regional differences of land use carbon emission (LUCE) in the Yangtze River Economic Belt and the path of coordinated emission reduction for regional sustainable development. Based on the LUCE estimation method, this study scientifically calculated the LUCE of the three major urban agglomerations of the Yangtze River Economic Belt (Yangtze River Delta, middle reaches of the Yangtze River, and Chengdu-Chongqing urban agglomeration) from 2010 to 2020. Kernel density estimation and the spatial convergence model were used to study the dynamic evolution, regional differences, and convergence characteristics of LUCE. The results showed that: ① The carbon absorption of forest land, water areas, grassland, and unused land were relatively small in terms of carbon emissions from cultivated land and construction land. The carbon emission of construction land increased gradually, whereas the carbon absorption of four carbon sinks fluctuated little during the study period. ② The core density curves of different urban agglomerations showed different distribution patterns, extensibility, and polarization characteristics but generally tended to be balanced. ③ From 2010 to 2020, the LUCE of the Yangtze River Economic Belt as a whole showed the spatio-temporal characteristics of increasing first and then decreasing and high in the east and low in the west. The LUCE of the central cities of the three urban agglomerations were at the highest level steadily, and stable coupling mechanisms had not been established between the economic development level and the ecological environment. ④ The LUCE of the three urban agglomerations in the Yangtze River Economic Belt all had absolute ß convergence and also had conditional ß convergence under the model control variables such as economic development level, urbanization level, industrial structure, population density, and environmental regulation, etc., and the conditional convergence speed was greater than the absolute convergence speed in each region. The convergence speed of the Yangtze River Delta urban agglomeration was the slowest. The above conclusions provide support for the coordinated emission reduction path of the three urban agglomerations in the Yangtze River Economic Belt and are also conducive to actively and steadily promoting the realization of the goals of carbon peak and carbon neutralization.

2.
World J Clin Cases ; 12(10): 1793-1798, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38660069

RESUMEN

BACKGROUND: Whether hyperbaric oxygen therapy (HBOT) can cause paradoxical herniation is still unclear. CASE SUMMARY: A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradually regained consciousness after surgery. HBOT was administered 22 d after surgery due to speech impairment. Paradoxical herniation appeared on the second day after treatment, and the patient's condition worsened after receiving mannitol treatment at the rehabilitation hospital. After timely skull repair, the paradoxical herniation was resolved, and the patient regained consciousness and had a good recovery as observed at the follow-up visit. CONCLUSION: Paradoxical herniation is rare and may be caused by HBOT. However, the underlying mechanism is unknown, and the understanding of this phenomenon is insufficient. The use of mannitol may worsen this condition. Timely skull repair can treat paradoxical herniation and prevent serious complications.

3.
J Reprod Immunol ; 155: 103780, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36481385

RESUMEN

The management of patients with poor ovarian response (POR) remains a major challenge for fertility specialists in in vitro fertilization-embryo transfer (IVF-ET). In this retrospective cohort study, we aimed to evaluate the clinical effect of sequential transfer on pregnancy outcomes in patients with POR. A total of 3579 POR patients who underwent the first frozen embryo transfer (FET) cycle were enrolled from January 2018 to April 2021. The patients were divided into three groups according to the embryo transfer (ET) strategy adopted: a study group that included POR patients in whom a cleavage-stage embryo (day 3) and a blastocyst (day 5/6) were transferred (sequential transfer group), and two control groups in whom two cleavage-stage embryos (D3-dET group) or two blastocysts (D5/6-dET group) were transferred. The study group was matched with the control groups at a ratio of 1:4 by propensity score matching (PSM). The main pregnancy outcomes measured were the live birth rate and multiple pregnancy rate. After PSM, the live birth rate in the sequential transfer group was significantly higher than that in the D3-dET group (44.2% vs. 34.3%, P = 0.019), and was similar to that in the D5/6-dET group (44.2% vs. 45.3%; P = 0.90). In addition, there was no increase in the risk of multiple pregnancy among POR patients undergoing sequential transfer compared with both D3-dET (26.7% vs. 25.6%, P = 0.85) and D5/6-dET (26.7% vs. 28.4%, P = 0.97) groups. These findings imply that sequential transfer is an effective option for POR patients and could be utilized after careful consideration.


Asunto(s)
Fertilización In Vitro , Resultado del Embarazo , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Transferencia de Embrión/efectos adversos , Índice de Embarazo , Blastocisto
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 235: 118315, 2020 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-32289732

RESUMEN

Direct exploration to differences between normal hair (NH) and alopecic hair (AH) at different degeneration stages is still lacking. To reveal compositional and structural variation of AH with reference to NH internally and externally, infrared spectroscopic imaging combined with scanning electron microscopy was applied to investigate integral changes of hair chemical profiles and surface texture structures, and infrared macro-fingerprinting analysis revealed detailed chemical compositions of NH and AH. Results showed that AH had excessive irregular laminated structures compared to NH, leading to a lower weight bearing capacity. Spatial distributions of lipids, phosphates, lipoproteins and phospholipids in hair transverse sections showed that their infrared absorptions were intensified and gradually centralized to medulla with average variable-areas increasing upto 2.3 folds (lipoproteins area changed from 13% in NH to 30% in AH)as the alopecia progressed. Extracted pixel spectra from the chemical images showed different fingerprint characteristics in 1075-1120 cm-1. Specifically, compared to NH, AH showed red shift of phosphate peaks, indicating the occurrence of phosphates transformation. In this study, in-situ visible and infrared chemical imaging directly revealed more irregular laminated scalps with decreasing weight bearing capacity and increasing distributive areas expanding to medulla of key components (phosphates, phospholipids, etc.) that were relevant to alopecia development from NH to AH, and offered a fast, eco-friendly and effective method for hair research.


Asunto(s)
Alopecia/diagnóstico por imagen , Cabello/fisiología , Cabello/ultraestructura , Lípidos/análisis , Lipoproteínas/análisis , Fosfatos/análisis , Espectrofotometría Infrarroja , Adulto , Humanos , Masculino , Microscopía Electrónica de Rastreo , Fosfolípidos/química , Análisis de Componente Principal , Cuero Cabelludo
5.
Mol Biol Rep ; 37(5): 2379-86, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19693692

RESUMEN

Genetic diversity and population structure of 9 populations of Bufo gargarizans with total 111 samples in China were assessed using seven microsatellite loci. The analysed microsatellite markers produced 161 alleles, varied from 9 to 38 alleles each locus. The number of alleles per population per locus ranged from 4.43 to 10.29. Polymorphic information content showed that all seven loci were highly informative (mean = 0.810 + or - 0.071). The average observed heterozygosity was less than the expected (0.353 + or - 0.051 and 0.828 + or - 0.067, respectively). All tested populations gave significant departures from Hardy-Weinberg equilibrium. Genetic differentiation among the populations was considerably high with the overall and pairwise F (ST) values (mean = 0.160 + or - 0.039), and showed fairly high level of inbreeding (indicated by a mean F (IS) value of 0.504 + or - 0.051) and global heterozygote deficit. In comparison to other amphibian studies; however, our results suggested that the level of genetic structuring in B. gargarizans was relatively low in the geographical scale of the study area. Interestingly, the speculated population bottleneck was found to be absent and the analyses provide only weak evidence for a recent contraction in size even though there was severe inbreeding (indicated by the F (IS) value) in the Chinese toad populations.


Asunto(s)
Bufonidae/genética , Variación Genética , Repeticiones de Microsatélite/genética , Animales , China , Sitios Genéticos/genética , Genética de Población , Geografía
6.
Biochem Genet ; 45(9-10): 697-711, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17879156

RESUMEN

The Chinese toad Bufo gargarizans has an extensive range, covering nearly all of China. This study addresses the population genetic structure of this toad and the relation to geographic location. Partial sequences of the mtDNA control region were obtained from 14 populations, 29 haplotypes were defined, and 73 variable sites were found, including 66 parsimony informative sites. All population genetic analyses indicated no clear geographic pattern in the distribution of haplotypes. The genetic divergence between the populations was significant. Phylogeographic analyses suggested that past fragmentation and/or long-distance colonization seemed to have shaped the present-day distribution of the haplotypes of B. gargarizans.


Asunto(s)
Bufonidae/genética , Animales , Secuencia de Bases , Teorema de Bayes , Bufonidae/clasificación , China , Cartilla de ADN/genética , ADN Mitocondrial/genética , Evolución Molecular , Variación Genética , Genética de Población , Geografía , Haplotipos , Modelos Genéticos , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Ácido Nucleico
7.
Gene ; 394(1-2): 25-34, 2007 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-17368759

RESUMEN

In this study, the complete nucleotide sequence (17,962 bp) of the mitochondrial DNA of Amolops tormotus was determined using polymerase chain reaction (PCR). The gene content, base composition and codon usage of A. tormotus conformed to those of typical vertebrate patterns. Among 22 tRNAs, the novel position of the tRNA-His gene was in the D-loop region, which was a novel mtDNA gene rearrangement in amphibians. Phylogenetic analyses were based on a 885-bp sequence of 12S and 16S rRNA for species of Amolops and other related species, concatenated sequences of the 11 protein-encoding genes of 13 species.


Asunto(s)
ADN Mitocondrial/genética , Ranidae/genética , Animales , Composición de Base/genética , Secuencia de Bases , Codón/genética , Cartilla de ADN/genética , ADN Mitocondrial/química , Duplicación de Gen , Reordenamiento Génico , Modelos Genéticos , Conformación de Ácido Nucleico , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico/genética , ARN Ribosómico 16S/genética , ARN de Transferencia/genética , ARN no Traducido/genética , Ranidae/clasificación
8.
Mitochondrion ; 6(4): 186-93, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16920409

RESUMEN

The complete mitochondrial genome of Bufo gargarizans was sequenced using overlapping polymerase chain reaction (PCR) amplicons (GenBank Accession No. DQ275350). The genome is 17,277 base pairs in length, containing 13 protein-coding genes (ATP6, ATP8, COI-III, ND1-6, ND4L, Cyt b), 2 ribosomal RNAs (12S rRNA and 16S rRNA), 22 transfer RNAs and a putative control region. We analyzed the sequence using bioinformatics methods comparing the obtained mtDNA sequence with other toads and frogs. Based on the concatenated nucleotide sequences of protein-coding genes, we constructed a phylogenetic tree with maximum likelihood (ML) and maximum parsimony (MP) methods and discussed the phylogenetic relationships among 11 species of Anura.


Asunto(s)
Bufonidae/genética , ADN Mitocondrial/genética , Orden Génico , Genes Mitocondriales , Genoma Mitocondrial , Animales , Análisis por Conglomerados , ADN Mitocondrial/química , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN
9.
J Sep Sci ; 29(17): 2684-91, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17313110

RESUMEN

A novel poly(dimethylsiloxane)/beta-cyclodextrin (PDMS/beta-CD) coating was prepared for solid-phase microextraction (SPME). The PDMS/beta-CD coating proved to have a porous structure, providing high surface areas and allowing for high extraction efficiency. The coating had a high thermal stability (340 degrees C) and a long lifetime due to its chemical binding to the fiber surface. Polar phenols and amines were used to evaluate the character of the coating fiber by headspace (HS) extraction and thermal desorption, followed by GC-FID analysis. Parameters that affected the extraction process were investigated; these include extraction time and temperature, desorption time, pH, and ionic strength of the solution. For phenols, the range of linearity of the method was 4-500 microg/L and the LOD was 1.3-2.1 microg/L. For amines, the range of linearity was 1-1000 microg/L and the LOD was 1.2-2.8 microg/L. The presence of beta-CD not only increases the thermal stability of the fiber coating, but also enhances its selectivity. Compared with commercially available SPME fibers, the new phases show better selectivity and sensitivity towards polar compounds.

10.
J Neurosurg ; 102(6): 1085-93, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16028768

RESUMEN

OBJECT: The authors examined whether delayed treatment with Mg++ would reduce brain infarction and improve electrophysiological and neurobehavioral recovery following cerebral ischemia-reperfusion. METHODS: Male Sprague-Dawley rats were subjected to right middle cerebral artery occlusion for 90 minutes followed by 72 hours of reperfusion. Magnesium sulfate (750 micromol/kg) or vehicle was given via intracarotid infusion at the beginning of reperfusion. Neurobehavioral outcome and somatosensory evoked potentials (SSEPs) were examined before and 72 hours after ischemia-reperfusion. Brain infarction was assessed after the rats had died. Before ischemia-reperfusion, stable SSEP waveforms were recorded after individual fore- and hindpaw stimulations. At 72 hours of perfusion the SSEPs recorded from ischemic fore- and hindpaw cortical fields were depressed in vehicle-injected animals and the amplitudes decreased to 19 and 27% of baseline, respectively (p < 0.001). Relative to controls, the amplitudes of SSEPs recorded from both ischemic fore- and hindpaw cortical field in the Mg++-treated animals were significantly improved by 23% (p < 0.005) and 39% (p < 0.001) of baselines, respectively. In addition, Mg++ improved sensory and motor neurobehavioral outcomes by 34% (p < 0.01) and 24% (p < 0.05), respectively, and reduced cortical (p < 0.05) and striatal (p < 0.05) infarct sizes by 42 and 36%, respectively. CONCLUSIONS: Administration of Mg++ at the commencement of reperfusion enhances electrophysiological and neurobehavioral recovery and reduces brain infarction after cerebral ischemia-reperfusion. Because Mg++ has already been used clinically, it may be worthwhile to investigate it further to see if it holds potential benefits for patients with ischemic stroke and for those who will undergo carotid endarterectomy.


Asunto(s)
Potenciales Evocados Somatosensoriales , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Ataque Isquémico Transitorio/tratamiento farmacológico , Magnesio/farmacología , Recuperación de la Función/efectos de los fármacos , Animales , Conducta Animal , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Cuerpo Estriado/patología , Cuerpo Estriado/fisiopatología , Infarto de la Arteria Cerebral Media/patología , Infarto de la Arteria Cerebral Media/fisiopatología , Inyecciones Intraarteriales , Ataque Isquémico Transitorio/patología , Ataque Isquémico Transitorio/fisiopatología , Masculino , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/patología , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
11.
Free Radic Biol Med ; 39(4): 495-510, 2005 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16043021

RESUMEN

Acute neuroprotective effects of cinnamophilin (CINN; (8R, 8'S)-4, 4'-dihydroxy-3, 3'-dimethoxy-7-oxo-8, 8'-neolignan), a novel antioxidant and free radical scavenger, were studied in a mouse model of transient middle cerebral artery (MCA) occlusion. CINN was administered intraperitoneally either 15 min before (pretreatment) or 2 h after the onset of MCA occlusion (postischemic treatment). Relative to vehicle-treated controls, animals pretreated with CINN, at 20-80 mg/kg, had significant reductions in brain infarction by 33-46% and improvements in neurobehavioral outcome. Postischemic administration with CINN (80 mg/kg) also significantly reduced brain infarction by 43% and ameliorated neurobehavioral deficits. Additionally, CINN administration significantly attenuated in situ accumulation of superoxide anions (O2-) in the boundary zones of infarct at 4 h after reperfusion. Consequently, CINN-treated animals exhibited significantly decreased levels of oxidative damage, as assessed by immunopositive reactions for 8-hydroxy-2'-deoxyguanosine (8-OHdG) and 4-hydroxynonenal (4-HNE), and the resultant inflammatory reactions at 24 h post-insult. It is concluded that CINN effectively reduced brain infarction and improved neurobehavioral outcome following a short-term recovery period after severe transient focal cerebral ischemia in mice. The finding of a decreased extent of reactive oxygen species and oxidative damage observed with CINN treatment highlights that its antioxidant and radical scavenging ability is contributory.


Asunto(s)
Antioxidantes/uso terapéutico , Isquemia Encefálica/prevención & control , Depuradores de Radicales Libres/uso terapéutico , Guayacol/análogos & derivados , Lignanos/uso terapéutico , Animales , Isquemia Encefálica/tratamiento farmacológico , Corteza Cerebral/irrigación sanguínea , Circulación Cerebrovascular/efectos de los fármacos , Guayacol/uso terapéutico , Infarto de la Arteria Cerebral Media/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Daño por Reperfusión/prevención & control , Factores de Tiempo
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