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1.
Rev Cardiovasc Med ; 25(5): 170, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-39076496

RESUMEN

Background: Transseptal puncture (TSP) performed with the Brockenbrough (BRK) needle is technically demanding and carries potential risks. The back end of the percutaneous transluminal coronary angioplasty (PTCA) guidewire is blunt and flexible, with good support, it can puncture the right ventricle-free wall, which is thicker than the atrial-septum. The guidewire is thin and easy to manipulate. This study evaluated the performance of TSP with a PTCA guidewire and microcatheter without a needle. Methods: The back end of a PTCA guidewire was advanced into the Tiger (TIG) catheter, within the SL1 sheath, to puncture the fossa ovalis (FO) under fluoroscopy. Subsequently, the microcatheter was inserted into the left atrium (LA) above the guidewire, and the front end of the guidewire was exchanged in the LA. After the puncture site was confirmed by contrast, the TIG catheter and a 0.032 inch wire were advanced into the LA. Finally, the sheath, with the dilator, was advanced over the wire into the LA. The safety margin of this method was tested in a pig model. Results: The puncture was successful in all seven pigs tested with a puncture-to-sheath entry time of < 20 minutes and no procedure-related complications. The method was successfully used to perform a difficult TSP in a patient with an extremely tortuous inferior vena cava, in whom puncture with a BRK needle had repeatedly failed. Conclusions: Cardiologists may use the PTCA guidewire and microcatheter as an alternative to the needle while performing TSP in special conditions, such as an extremely tortuous inferior vena cava.

2.
J Nat Prod ; 87(1): 141-151, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38128907

RESUMEN

Twelve new austalide meroterpenoids (1-12) were isolated from the endophytic fungus Diaporthe sp. XC1211. Their structures were elucidated by extensive spectroscopic analysis. The absolute configurations of compounds 1, 3, 4, and 6 were established by single-crystal X-ray diffraction, whereas those for the others were established by experimental electronic circular dichroism (ECD) data analysis. Compounds 1-12 represent a rare class of austalides with a 24α-CH3. Compounds 2 and 5 demonstrated potent proliferation inhibitory effects against LPS-induced B cells with IC50 values of 6.7 (SI = 3.6) and 3.8 (SI > 13) µM, respectively. Compounds 2 and 5 decreased the secretion of IL-6 in LPS-induced B cells in a dose-dependent manner.


Asunto(s)
Hongos , Lipopolisacáridos , Estructura Molecular , Lipopolisacáridos/farmacología , Cristalografía por Rayos X , Dicroismo Circular
3.
BMC Vet Res ; 20(1): 40, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38297289

RESUMEN

BACKGROUND: mcr-1-positive Escherichia coli has emerged as a significant threat to human health, veterinary health, and food safety in recent years. After the prohibition of colistin as a feed additive in animal husbandry in China, a noticeable reduction in both colistin resistance and the prevalence of mcr-1 was observed in E. coli from animals and humans. OBJECTIVES: To assess the prevalence of the colistin resistance gene mcr-1 and characterize its genetic context in E. coli strains derived from fecal and meat samples from food-producing animals in China. METHODS: A total of 1,353 fecal samples and 836 food samples were collected between 2019 and 2020 in China. E. coli isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and their susceptibility to colistin were determined using the broth microdilution method. The colistin-resistant E. coli isolates were screened for the presence of mcr by PCR analysis and sequencing. The minimal inhibitory concentrations (MICs) of 15 antimicrobial agents against the mcr-1-positive strains were further tested using the agar dilution method, conjugation assays were performed, and whole genome sequencing was performed using Illumina HiSeq. RESULTS: In total, 1,403 E. coli strains were isolated. Thirteen isolates from chicken meat (n = 7), chickens (n = 3), and pigs (n = 3) were resistant to colistin with MIC values of 4 to 16 mg/L, and carried mcr-1. All mcr-1-positive strains, except for isolate AH20PE105, contained multiple resistance genes and exhibited multidrug-resistant phenotypes. They belonged to 10 sequence types (STs), including a novel ST (ST14521). mcr-1 was located on IncI2 (n = 9), IncX4 (n = 2), and IncHI2 (n = 2) plasmids, which were highly similar to other mcr-1-carrying plasmids sharing the same incompatibility type. Seven mcr-1-carrying plasmids could be successfully conjugally transferred to E. coli C600. CONCLUSIONS: While the low prevalence of mcr-1 (0.93%) identified in this study may not immediately seem alarming, the very emergence of this gene merits attention given its implications for colistin resistance and public health. Hence, ongoing surveillance of mcr-1 in E. coli remains crucial.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Animales , Humanos , Porcinos , Colistina/farmacología , Proteínas de Escherichia coli/genética , Antibacterianos/farmacología , Prevalencia , Pollos/genética , Plásmidos , China/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Farmacorresistencia Bacteriana/genética
4.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34282014

RESUMEN

Asian summer monsoon (ASM) variability and its long-term ecological and societal impacts extending back to Neolithic times are poorly understood due to a lack of high-resolution climate proxy data. Here, we present a precisely dated and well-calibrated tree-ring stable isotope chronology from the Tibetan Plateau with 1- to 5-y resolution that reflects high- to low-frequency ASM variability from 4680 BCE to 2011 CE. Superimposed on a persistent drying trend since the mid-Holocene, a rapid decrease in moisture availability between ∼2000 and ∼1500 BCE caused a dry hydroclimatic regime from ∼1675 to ∼1185 BCE, with mean precipitation estimated at 42 ± 4% and 5 ± 2% lower than during the mid-Holocene and the instrumental period, respectively. This second-millennium-BCE megadrought marks the mid-to late Holocene transition, during which regional forests declined and enhanced aeolian activity affected northern Chinese ecosystems. We argue that this abrupt aridification starting ∼2000 BCE contributed to the shift of Neolithic cultures in northern China and likely triggered human migration and societal transformation.

5.
J Sci Food Agric ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225323

RESUMEN

This study aimed to investigate the influence of varying concentrations of Flammulina velutipes powder (FVP) (0, 4, 8, 12, 16, and 20 g L-1, based on FVP weight per liter of emulsion) on the stability, rheological properties, microstructure, and interfacial protein content of chicken myofibrillar protein (MP) emulsions under low-salt conditions. Visual assessment and the Turbiscan stability index revealed that the stability of MP emulsions improved with increasing FVP concentration. The greatest stability was achieved when the FVP concentration was 16 gL-1. The incorporation of FVP enhanced the elasticity and viscosity of the emulsions by forming a dense three-dimensional network structure. The droplet size of the emulsions initially decreased and then increased with increasing FVP concentration. The addition of FVP increased the amount of protein absorbed by the emulsion layer. Flammulina velutipes powder is promising as a stabilizer that could improve the emulsifying and functional properties of low-salt myofibrillar protein emulsions. © 2024 Society of Chemical Industry.

6.
Chemistry ; 29(44): e202300554, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37249393

RESUMEN

The field of anion supramolecular chemistry has received more and more attention in recent years. Anions with diverse types and geometries have been widely used for the synthesis of ionic spin crossover (SCO) complexes. This review is devoted to anion effects on the molecular, supramolecular structures and magnetic properties of discrete SCO compounds. Firstly, typical anions used in the synthesis of these compounds are briefly summarized according to their various geometries. This is followed by a collection of representative examples of anion-based SCO compounds, whose SCO properties are analyzed in terms of supramolecular interactions, geometry and charge of anions. In the third part, anion effects on SCO complexes of different kinds of metal centers and ligands are outlined and finally remarks on the synthesis new type of ionic SCO complexes in the future are described.

7.
Antimicrob Agents Chemother ; 66(7): e0007322, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35758720

RESUMEN

Metronidazole (Met) is the first choice for treating Helicobacter pylori (Hp). However, Hp is easy to resistant, making Met unable to be widely used. How to overcome Hp's Met resistance is still an issue. In this study, Met was used as the primary raw material with linolenic acid to prepare a novel compound-linolenic acid-metronidazole (Lla-Met). The MIC, minimum bactericidal concentration (MBC), colonization amount of Hp in gastric mucosa, etc., were evaluated, respectively. Lla-Met was successfully prepared by the detection of nuclear magnetic resonance, etc., and its MIC and MBC to Hp were 2~4 µg/mL, 8~16 µg/mL. Moreover, in vivo experiments, Lla-Met significantly reduced the colonization of drug-resistant Hp in gastric mucosa. In the toxicity test, Lla-Met inhibited rate to GES-1 and BGC823 cells were 15% at 128 µg/mL; the mice were administered 10 times treatment Lla-Met treatment (240 mg/kg), have no difference significant injuries were found in their stomach, liver, spleen, kidney, and weight. In addition, Hp G27 continued for 18 days in vitro with sub-Lla-Met concentration, G27 did not show drug resistance to Lla-Met; Lla-Met did not exert an effect on non-Hp species with 128 µg/mL; Compared with a neutral environment, when the acid concentration is 3.0, Lla-Met is not decomposed and has better stability. Conclusion: Lla-Met, a newly prepared compound, has relatively well antibacterial of Met-resistant and sensitive Hp, with a capability of overcoming the metronidazole resistance of Hp.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Claritromicina/farmacología , Resistencia a Medicamentos , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Metronidazol/farmacología , Metronidazol/uso terapéutico , Ratones , Ácido alfa-Linolénico/farmacología
8.
Acta Clin Croat ; 61(2): 193-197, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36818924

RESUMEN

The aim was to investigate detection of pulmonary alveolar lavage fluid tuberculosis DNA by real-time fluorescent polymerase chain reaction (RT-PCR) combined with clinical application of the sputum smear-negative pulmonary tuberculosis diagnosis with TB interferon-γ release assay (TB-IGRA). From October 2014 to October 2015, 632 outpatients and inpatients treated in our hospital were randomly selected, of which 459 patients as the research group managed with RT-PCR detection combined with TB-IGRA and 173 patients as the control group undergoing electronic bronchoscopy alveolar lavage fluid detection, with detection results statistically evaluated. The positive rate in the research group was 96.51%, i.e. significantly higher than that in the control group (66.47%), yielding a statistically significant difference (χ2=109.68, p=0.00). The true positive rate was 97.7% in the research group and 67.92% in the control group; the true positive rate was significantly higher in the research group patients as compared with the control group, yielding a statistically significant difference (χ2=112.04, p=0.00). The sensitivity and specificity, as well as Youden index were significantly higher in the research group as compared with the control group. In conclusion, TB DNA detection by RT-PCR combined with TB-IGRA is a very good method of diagnosing tuberculosis, and it can be implemented in clinical diagnosis of pulmonary tuberculosis.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Humanos , Ensayos de Liberación de Interferón gamma/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Esputo , Tuberculosis/diagnóstico , Tuberculosis Pulmonar/diagnóstico , Sensibilidad y Especificidad , ADN
9.
Molecules ; 26(21)2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34771127

RESUMEN

Qingzhuan tea (QZT) is a typical Chinese dark tea that has a long-time manufacturing process. In the present study, liquid chromatography coupled with tandem mass spectrometry was used to study the chemical changes of tea samples during QZT processing. Untargeted metabolomics analysis revealed that the pile-fermentation and turnover (post-fermentation, FT) was the crucial stage in transforming the main compounds of QZT, whose contents of flavan-3-ols and flavonoids glycosides were decreased significantly. The bioactivities, including the antioxidant capacities and inhibitory effects on α-amylase and α-glucosidase, were also reduced after the FT process. It was suggested that although the QZT sensory properties improved following pile-fermentation and aging, the bioactivities remained restrained. Correlation analysis indicated that the main galloylated catechins and flavonoid glycosides were highly related to their antioxidant capacity and inhibitory effects on α-amylase and α-glucosidase.


Asunto(s)
Antioxidantes/metabolismo , Bioensayo , Inhibidores de Glicósido Hidrolasas/metabolismo , Metabolómica , Té/metabolismo , Antioxidantes/química , Antioxidantes/farmacología , China , Flavonoides/química , Flavonoides/metabolismo , Flavonoides/farmacología , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Glicósidos/química , Glicósidos/metabolismo , Glicósidos/farmacología , Té/química , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo , alfa-Glucosidasas/metabolismo
10.
Bull Environ Contam Toxicol ; 106(3): 507-515, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33559032

RESUMEN

Heavy metal contamination of soil is of increasing concern because of its potential risk to human health. In this study, two AMFs (Rhizophagus intraradices and Funneliformis mosseae) substantially increased the biomass of bashfulgrass in Zn-contaminated soil, even at Zn levels of up to 600 mg kg-1. Zn uptake in R. intraradices- and F. mosseae-mycorrhizal bashfulgrass was increased by 40-fold and 7-fold, respectively, when plants grown in Zn-contaminated (400 mg kg-1) soil. Elemental analysis showed that neither AMF had an effect on Zn concentration in plant tissues, including the roots and shoots. However, a significant increase of phosphorus (P) concentration was observed, suggesting the increased is from the improved use efficiency of soil nutrients by AMFs. Comparing the two AMFs, better growth performance with more biomass occurred with R. intraradices-inoculated bashfulgrass in Zn-contaminated soil. This is consistent with R. intraradices being more tolerant to Zn than F. mosseae, indicated by a higher colonization percentage in bashfulgrass roots. Taken together, our data indicate that AMFs possibly improve acquisition and translocation of P to promote increased biomass. Moreover, mycorrhiza did not enhance Zn accumulation in shoots and roots of bashfulgrass at the same Zn level. In the future, developing AMF (especially R. intraradices) inoculation of plants might be a desirable means of safe production of ornamental plants in metal-polluted soil.


Asunto(s)
Mimosa , Micorrizas , Contaminantes del Suelo , Hongos , Humanos , Fósforo , Raíces de Plantas , Suelo , Contaminantes del Suelo/toxicidad , Zinc/toxicidad
11.
Med Sci Monit ; 26: e921510, 2020 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-32238796

RESUMEN

BACKGROUND SOX7 exerts a repressing effect against tumors and imposes vital influences on malignancies. Our research discussed the importance of SOX7 in breast cancer prognoses. MATERIAL AND METHODS SOX7 mRNA expression in breast cancer tissues samples and matched adjacent normal controls of breast cancer patients was measured by quantitative real-time-polymerase chain reaction (qRT-PCR). The relationship of SOX7 with clinicopathological characteristics were analyzed via chi-square test. The association of SOX7 levels with clinical outcomes was evaluated adopting the Kaplan-Meier method and multivariate Cox proportional hazards regression model. RESULTS SOX7 mRNA degree of expression exhibited a declining tendency in breast cancer tissue compared to paired bordering normal tissue specimens (P<0.001). In addition, the reduced SOX7 degree of expression had a strong correlation to larger cancer mass dimension (P=0.006) and lymph node metastasis (P=0.001). Survival analysis revealed that the overall survival (OS) time was much shorter among cases harboring low SOX7 degree of expression compared to high degree of expression (P=0.005). Moreover, SOX7 expression alone could predict OS among breast cancer patients (hazard ratio=3.956, 95% confidence interval=1.330-11.772, P=0.013). CONCLUSIONS SOX7 expression was downregulated in breast cancer tissues, and it could function as a useful prognostic marker in breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Factores de Transcripción SOXF/metabolismo , Biomarcadores de Tumor/genética , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Regulación hacia Abajo , Femenino , Perfilación de la Expresión Génica , Humanos , Metástasis Linfática , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Transcripción SOXF/genética , Análisis de Supervivencia
13.
Mikrochim Acta ; 186(8): 576, 2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31346739

RESUMEN

A composite probe has been developed for fluorometric determination and imaging of phosphate in real water samples and in cells. The method is based on the use of weakly blue fluorescent bromine-doped carbon dots (C-dots) containing aromatic carbon-bromine groups and loaded with Fe3+ ions. The carboxy, phenolic hydroxy and aldehyde groups on the surface of the C-dots can coordinate with Fe3+ to form an adsorbed complex that reduces the blue fluorescence through an inner filter effect. If phosphate is added, it will capture Fe3+ on the surface of C-dots and restore fluorescence by ~88% via a displacement approach. The probe, best operated at excitation/emission maxima of 370/418 nm, has a linear response in the 0.4 to 22 µM phosphate concentration range and a 0.25 µM of detection limit. The relative standard deviation (at a phosphate level of 8.0 µM) is 3.6% (for n = 5). The method was applied to confocal imaging of phosphate in HeLa cells. Graphical abstractSchematic representation of the synthesis of bromine-doped carbon dots (C-dots) by a "one-step" approach. They are shown to be capable of (a) detecting phosphate in real water samples through the displacement approach, and (b) of imaging intracellular phosphate.


Asunto(s)
Compuestos Férricos/química , Colorantes Fluorescentes/química , Fosfatos/análisis , Puntos Cuánticos/química , Espectrometría de Fluorescencia , Bromo/química , Carbono/química , Agua Dulce/análisis , Células HeLa , Humanos , Iones/química , Límite de Detección , Microscopía Confocal
14.
Proc Natl Acad Sci U S A ; 111(8): 2903-8, 2014 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-24516152

RESUMEN

An annually resolved and absolutely dated ring-width chronology spanning 4,500 y has been constructed using subfossil, archaeological, and living-tree juniper samples from the northeastern Tibetan Plateau. The chronology represents changing mean annual precipitation and is most reliable after 1500 B.C. Reconstructed precipitation for this period displays a trend toward more moist conditions: the last 10-, 25-, and 50-y periods all appear to be the wettest in at least three and a half millennia. Notable historical dry periods occurred in the 4th century BCE and in the second half of the 15th century CE. The driest individual year reconstructed (since 1500 B.C.) is 1048 B.C., whereas the wettest is 2010. Precipitation variability in this region appears not to be associated with inferred changes in Asian monsoon intensity during recent millennia. The chronology displays a statistical association with the multidecadal and longer-term variability of reconstructed mean Northern Hemisphere temperatures over the last two millennia. This suggests that any further large-scale warming might be associated with even greater moisture supply in this region.


Asunto(s)
Cambio Climático/historia , Lluvia , Nieve , Árboles/crecimiento & desarrollo , Geografía , Historia Antigua , Tibet , Factores de Tiempo , Árboles/anatomía & histología
15.
Cell Physiol Biochem ; 34(5): 1723-32, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25428728

RESUMEN

AIMS: Neutrophils can synthesize leukotriene B4 (LTB4) by activating the 5-lipoxygenase (5-LO)signaling pathway. LTB4 is a pro-inflammatory mediator associated with the etiology and progression of atherosclerosis. It can increase function and number of neutrophils in an autocrine manner. Since hypercholesterolemia is associated with an increase in the number and function of neutrophils, we hypothesized that this effect could be mediated through increased production of LTB4 in neutrophils. METHODS/RESULTS: Hypercholesterolemia was modeled in Wistar rats by feeding them with a high cholesterol diet. The induction of hypercholesterolemia caused an increase in the plasma levels of LTB4, following lipopolysaccharide stimulation. This effect was recapitulated in vitro, both in the presence and absence of stimulation with the activator of 5-LO, A23187. Neutrophils in hypercholesterolemia rats expressed similar total levels of 5-LO as control rats, but displayed increased nuclear localization of 5-LO, as well as elevated levels of phosphorylated 5-LO and ERK1/2. In vitro, MßCD/cholesterol complexes enriched cholesterol in neutrophils, resulted in similar changes in 5-LO/LTB4. In addition, these alterations could be inhibited with the ERK inhibitor PD98059. CONCLUSION: Hypercholesterolemia increases LTB4 production in neutrophils by increasing the nuclear localization of 5-LO, which is the result of its phosphorylation by activated ERK1/2.


Asunto(s)
Araquidonato 5-Lipooxigenasa/metabolismo , Núcleo Celular/metabolismo , Hipercolesterolemia/metabolismo , Leucotrieno B4/metabolismo , Neutrófilos/metabolismo , Animales , Calcimicina/farmacología , Colesterol/metabolismo , Femenino , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos
16.
Antonie Van Leeuwenhoek ; 105(5): 971-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24677143

RESUMEN

A red-pink, Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, designated strain DK6-37 was isolated from the permafrost region of Qilian Mountains in northwest of China. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that this isolate represents a novel member of the genus Hymenobacter, with low sequence similarities (<97 %) to recognized Hymenobacter species. Optimum growth was observed at 28 °C, pH 7.0 and 0 % NaCl. The strain was found to contain MK-7 as the predominant menaquinone. The polar lipids were identified as phosphatidylethanolanmine, two unknown aminophospholipids, one unknown aminolipid and three unknown polar lipids. The major fatty acids were identified as summed feature 3 (C16:1 ω7c/C16:1 ω6c as defined by MIDI), summed feature 4 (anteiso-C17:1 B/iso-C17:1 I), C16:1 ω5c, iso-C17:0 3-OH, iso-C15:0 and C18:0. The DNA G + C content was determined to be 67.4 mol %. On the basis of the polyphasic evidence presented, it is proposed that strain DK6-37 represents a novel species of the genus Hymenobacter, for which the name Hymenobacter qilianensis sp. nov. is proposed. The type strain is DK6-37(T) (= CGMCC 1.12720(T) = JCM 19763(T)).


Asunto(s)
Cytophagaceae/clasificación , Cytophagaceae/aislamiento & purificación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , Análisis por Conglomerados , Cytophagaceae/genética , Cytophagaceae/fisiología , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Datos de Secuencia Molecular , Fosfolípidos/análisis , Filogenia , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
17.
Environ Monit Assess ; 186(9): 5883-95, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24865385

RESUMEN

Aquatic organisms' tolerance to water pollution is widely used to monitor and assess freshwater ecosystem health. Tolerance values (TVs) estimated based on statistical analyses of species-environment relationships are more objective than those assigned by expert opinion. Region-specific TVs are the basis for developing accurate bioassessment metrics particularly in developing countries, where both aquatic biota and their responses to human disturbances have been poorly documented. We used principal component analysis to derive a synthetic gradient for four stressor variables (total nitrogen, total phosphorus, dissolved oxygen, and % silt) based on 286 sampling sites in the Taihu Lake and Qiantang River basins (Yangtze River Delta), China. We used the scores of taxa on the first principal component (PC1), which explained 49.8% of the variance, to estimate the tolerance values (TV(r)) of 163 macroinvertebrates taxa that were collected from at least 20 sites, 81 of which were not included in the Hilsenhoff TV lists (TV(h)) of 1987. All estimates were scaled into the range of 1-10 as in TV(h). Of all the taxa with different TVs, 46.3% of TV(r) were lower and 52.4% were higher than TV(h). TV(r) were significantly (p < 0.01, Fig. 2), but weakly (r(2) = 0.34), correlated with TVh. Seven biotic metrics based on TVr were more strongly correlated with the main stressors and were more effective at discriminating references sites from impacted sites than those based on TV(h). Our results highlight the importance of developing region-specific TVs for macroinvertebrate-based bioassessment and to facilitate assessment of streams in China, particularly in the Yangtze River Delta.


Asunto(s)
Monitoreo del Ambiente/métodos , Invertebrados/fisiología , Contaminantes del Agua/toxicidad , Adaptación Fisiológica , Animales , Organismos Acuáticos/fisiología , Biota , China , Ecosistema , Invertebrados/clasificación , Ríos/química , Contaminantes del Agua/análisis , Contaminación del Agua/análisis , Contaminación del Agua/estadística & datos numéricos
18.
Zhongguo Gu Shang ; 37(6): 6295-34, 2024 Jun 25.
Artículo en Zh | MEDLINE | ID: mdl-38910389

RESUMEN

As one of the common traumatic diseases in clinical practice, peripheral nerve injury (PIN) often causes nerve pain, abnormal reflexes, autonomic disorders, and even sensorimotor disorders due to the slow regeneration rate after injury, which seriously affects body function. Even as the gold standard of treatment, autologous nerve transplantation has limitations such as limited donor area and donor injury, which greatly limits its clinical application effect. Therefore, the preparation of artificial nerve grafts suitable for clinical practice has become the future development trend of peripheral nerve injury treatment, and the repair of injury defects and the promotion of nerve regeneration have also become research hotspots in tissue engineering and regenerative medicine. In recent years, extensive research has been carried out on nerve guidance conduits (NGCs) in the field of nerve regeneration and repair, in which scaffold materials and internal fillers have also become the focus of research as the core elements of neural catheters, and a series of achievements have been made in the application of new materials, embedding stem cells/precursor cells, and developing trophic factors and drug-loaded sustained-release systems. Therefore, this paper focuses on the application progress of hydrogel and its related derivative materials in the field of peripheral nerve injury repair, and provides new ideas for promoting the related research of tissue engineering and clinical medicine.


Asunto(s)
Hidrogeles , Regeneración Nerviosa , Traumatismos de los Nervios Periféricos , Traumatismos de los Nervios Periféricos/terapia , Traumatismos de los Nervios Periféricos/cirugía , Humanos , Regeneración Nerviosa/efectos de los fármacos , Animales , Ingeniería de Tejidos/métodos
19.
BMC Genom Data ; 25(1): 57, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858616

RESUMEN

The Quercus L. species is widely recognized as a significant group in the broad-leaved evergreen forests of tropical and subtropical East Asia. These plants hold immense economic value for their use as firewood, furniture, and street trees. However, the identification of Quercus species is considered challenging, and the relationships between these species remain unclear. In this study, we sequenced and assembled the chloroplast (cp.) genomes of four Quercus section Cyclobalanopsis species (Quercus disciformis, Quercus dinghuensis, Quercus blackei, and Quercus hui). Additionally, we retrieved six published cp. genome sequences of Cyclobalanopsis species (Quercus fleuryi, Quercus pachyloma, Quercus ningangensis, Quercus litseoides, Quercus gilva, and Quercus myrsinifolia). Our aim was to perform comparative genomics and phylogenetic analyses of the cp. whole genome sequences of ten Quercus section Cyclobalanopsis species. The results revealed that: (1) Quercus species exhibit a typical tetrad structure, with the cp. genome lengths of the newly sequenced species (Q. disciformis, Q. dinghuensis, Q. blakei, and Q. hui) being 160,805 bp, 160,801 bp, 160,787 bp, and 160,806 bp, respectively; (2) 469 SSRs were detected, among which A/T base repeats were the most common; (3) no rearrangements or inversions were detected within the chloroplast genomes. Genes with high nucleotide polymorphism, such as rps14-psaB, ndhJ-ndhK, rbcL-accD, and rps19-rpl2_2, provided potential reference loci for molecular identification within the Cyclobalanopsis section; (4) phylogenetic analysis showed that the four sections of Cyclobalanopsis were grouped into sister taxa, with Q. hui being the first to diverge from the evolutionary branch and Q. disciformis being the most closely related to Q. blackei. The results of this study form the basis for future studies on taxonomy and phylogenetics.


Asunto(s)
Genoma del Cloroplasto , Filogenia , Quercus , Quercus/genética , Genoma del Cloroplasto/genética
20.
Front Plant Sci ; 15: 1430191, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224852

RESUMEN

The genus Quercus L. is widely acknowledged as a significant assemblage within East Asia tropical and subtropical broadleaf evergreen forests, possessing considerable economic importance. Nevertheless, the differentiation of Quercus species is deemed arduous, and the interrelations among these species remain enigmatic. Leveraging Illumina sequencing, we undertook the sequencing and assembly of the chloroplast (cp) genomes of seven species belonging to Quercus section Cyclobalanopsis (Quercus argyrotricha, Q. augustinii, Q. bambusifolia, Q. bella, Q. edithiae, Q. jenseniana, and Q. poilanei). Furthermore, we collated three previously published cp genome sequences of Cyclobalanopsis species (Q. litseoides, Q. obovatifolia, and Q. saravanensis). Our primary objective was to conduct comparative genomics and phylogenetic analyses of the complete cp genomes of ten species from Quercus section Cyclobalanopsis. This investigation unveiled that Quercus species feature a characteristic circular tetrad structure, with genome sizes ranging from 160,707 to 160,999 base pairs. The genomic configuration, GC content, and boundaries of inverted repeats/single copy regions exhibited marked conservation. Notably, four highly variable hotspots were identified in the comparative analysis, namely trnK-rps16, psbC-trnS, rbcL-accD, and ycf1. Furthermore, three genes (atpF, rpoC1, and ycf2) displayed signals of positive selection pressure. Phylogenetic scrutiny revealed that the four sections of Cyclobalanopsis clustered together as sister taxa. The branch support values ranged from moderate to high, with most nodes garnering 100% support, underscoring the utility of cp genomic data in elucidating the relationships within the genus. Divergence time analysis revealed that Section Cyclobalanopsis represents the earliest type of Quercus genus. The outcomes of this investigation establish a foundation for forthcoming research endeavors in taxonomy and phylogenetics.

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