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1.
Nature ; 542(7641): 372-376, 2017 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-28114303

RESUMEN

Mitochondria are double-membraned organelles with variable shapes influenced by metabolic conditions, developmental stage, and environmental stimuli. Their dynamic morphology is a result of regulated and balanced fusion and fission processes. Fusion is crucial for the health and physiological functions of mitochondria, including complementation of damaged mitochondrial DNAs and the maintenance of membrane potential. Mitofusins are dynamin-related GTPases that are essential for mitochondrial fusion. They are embedded in the mitochondrial outer membrane and thought to fuse adjacent mitochondria via combined oligomerization and GTP hydrolysis. However, the molecular mechanisms of this process remain unknown. Here we present crystal structures of engineered human MFN1 containing the GTPase domain and a helical domain during different stages of GTP hydrolysis. The helical domain is composed of elements from widely dispersed sequence regions of MFN1 and resembles the 'neck' of the bacterial dynamin-like protein. The structures reveal unique features of its catalytic machinery and explain how GTP binding induces conformational changes to promote GTPase domain dimerization in the transition state. Disruption of GTPase domain dimerization abolishes the fusogenic activity of MFN1. Moreover, a conserved aspartate residue trigger was found to affect mitochondrial elongation in MFN1, probably through a GTP-loading-dependent domain rearrangement. Thus, we propose a mechanistic model for MFN1-mediated mitochondrial tethering, and our results shed light on the molecular basis of mitochondrial fusion and mitofusin-related human neuromuscular disorders.


Asunto(s)
GTP Fosfohidrolasas/química , GTP Fosfohidrolasas/metabolismo , Guanosina Trifosfato/metabolismo , Mitocondrias/química , Mitocondrias/metabolismo , Dinámicas Mitocondriales , Proteínas de Transporte de Membrana Mitocondrial/química , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Secuencia de Aminoácidos , Biocatálisis , Cristalografía por Rayos X , GTP Fosfohidrolasas/genética , Humanos , Hidrólisis , Fusión de Membrana , Potenciales de la Membrana , Proteínas de Transporte de Membrana Mitocondrial/genética , Membranas Mitocondriales/química , Membranas Mitocondriales/metabolismo , Modelos Moleculares , Dominios Proteicos , Multimerización de Proteína , Triptófano/metabolismo
2.
Molecules ; 28(22)2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-38005263

RESUMEN

Photocatalytic technology for inactivating bacteria in water has received much attention. In this study, we reported a dark-light dual-mode sterilized g-C3N4/chitosan/poly (vinyl alcohol) hydrogel (g-CP) prepared through freeze-thaw cycling and an in situ electron-beam radiation method. The structures and morphologies of g-CP were confirmed using Fourier infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), solid ultraviolet diffuse reflectance spectroscopy (UV-vis DRS), and Brunauer-Emmett-Teller (BET). Photocatalytic degradation experiments demonstrated that 1 wt% g-CP degraded rhodamine B (RhB) up to 65.92% in 60 min. At the same time, g-CP had good antimicrobial abilities for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 4 h. The shapes of g-CP were adjustable (such as bar, cylinder, and cube) and had good mechanical properties and biocompatibility. The tensile and compressive modulus of 2 wt% g-CP were 0.093 MPa and 1.61 MPa, respectively. The Cell Counting Kit-8 (CCK-8) test and Hoechst33342/PI double staining were used to prove that g-CP had good biocompatibility. It is expected to be applied to environmental sewage treatment and wound dressing in the future.


Asunto(s)
Escherichia coli , Staphylococcus aureus , Nanogeles , Electrones , Microscopía Electrónica de Rastreo
3.
Nucleic Acids Res ; 48(5): 2733-2748, 2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32009146

RESUMEN

Family with sequence similarity (FAM46) proteins are newly identified metazoan-specific poly(A) polymerases (PAPs). Although predicted as Gld-2-like eukaryotic non-canonical PAPs, the detailed architecture of FAM46 proteins is still unclear. Exact biological functions for most of FAM46 proteins also remain largely unknown. Here, we report the first crystal structure of a FAM46 protein, FAM46B. FAM46B is composed of a prominently larger N-terminal catalytic domain as compared to known eukaryotic PAPs, and a C-terminal helical domain. FAM46B resembles prokaryotic PAP/CCA-adding enzymes in overall folding as well as certain inter-domain connections, which distinguishes FAM46B from other eukaryotic non-canonical PAPs. Biochemical analysis reveals that FAM46B is an active PAP, and prefers adenosine-rich substrate RNAs. FAM46B is uniquely and highly expressed in human pre-implantation embryos and pluripotent stem cells, but sharply down-regulated following differentiation. FAM46B is localized to both cell nucleus and cytosol, and is indispensable for the viability of human embryonic stem cells. Knock-out of FAM46B is lethal. Knock-down of FAM46B induces apoptosis and restricts protein synthesis. The identification of the bacterial-like FAM46B, as a pluripotent stem cell-specific PAP involved in the maintenance of translational efficiency, provides important clues for further functional studies of this PAP in the early embryonic development of high eukaryotes.


Asunto(s)
Células Madre Embrionarias Humanas/metabolismo , Nucleotidiltransferasas/metabolismo , Polinucleotido Adenililtransferasa/metabolismo , Células Procariotas/metabolismo , Animales , Biocatálisis , Línea Celular , Supervivencia Celular , Desarrollo Embrionario , Humanos , Modelos Moleculares , Nucleotidiltransferasas/química , Nucleotidiltransferasas/genética , Polinucleotido Adenililtransferasa/química , Unión Proteica , Dominios Proteicos , ARN/metabolismo , Especificidad por Sustrato , Xenopus
4.
Plant Dis ; 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-33147123

RESUMEN

As an economically important tropical and subtropical fruit crop, passion fruit (Passiflora edulis Sims) is widely planted in many provinces of southern China. In April 2017, postharvest fruit rot was observed on 15% to 25% of passion fruit in several fruit markets of Zhanjiang City in Guangdong Province. Initial disease symptoms on infected fruit were irregular, brown, water-soaked lesions, which enlarged into large black and sunken patches. Lesions were usually covered with an abundance of little black dots (pycnidia) and black-gray hyphae. For the pathogen isolation, fifteen symptomatic fruit were randomly collected from three local markets. Fourteen single-spore fungal isolates with similar morphology ware isolated from the infected tissues. Two isolates (ZW 49-1 and ZW 50-1) were randomly selected to further study. The colonies on PDA were initially greyish-white and became dark-gray with age. Abundant globular and irregular pycnidia were observed after incubation at 25 °C for 3 weeks. The conidia of the fungus were initially hyaline, unicellular, apex rounded, thick-walled, and ellipsoid, becoming dark brown, bicellular with longitudinal striations at maturity, 26.4 ± 2.5 × 13.4 ± 1.2 µm (n = 50). The morphology of the fungus resembled Lasiodiplodia theobromae (Pat.) Griff. & Maubl. (Phillips et al. 2013). To confirm species identification, the partial internal transcribed spacer (ITS) region of rDNA, translation elongation factor-alpha (EF1-α) and ß-tubulin (TUB) gene were amplified from genomic DNA of the two isolates with the ITS1/ITS4, EF1-688F/EF1-986R, and Bt2a/Bt2b primers, respectively (Glass and Donaldson 1995; Alves et al. 2008; White et al. 1990). Base on the BLASTn analysis, the ITS (MT644473, MT644474), EF1-α (MT649210, MT649211) and TUB (MT649212, MT649213) sequences of both isolates were 100%, 99% and 100% similarity to the L. theobromae CBS 164.96 ex-type sequences in the NCBI database (AY640255, AY640258, and KU887532, respectively) (Phillips et al. 2013). For pathogenicity test, asymptomatic passion fruit were previously disinfested in 0.5 % sodium hypochlorite and superficially wounded with a sterile needle. Five-mm-diameter plugs with mycelial taken from 5-day-old PDA colonies were placed on the wounds. Sterile PDA plugs were used as negative controls. Each treatment had five replicates and the test was repeated twice. Fruit were maintained in plastic boxes to keep at 25°C for one week. One week after inoculation, gray mycelia had covered a majority of the fruit surface and caused a black, sunken rot. The inoculated fungus was reisolated and confirmed as L. theobromae by morphological characteristics. The mock inoculated fruit remained asymptomatic. The occurrence of fruit rot on passion fruit caused by L. theobromae was reported in Taiwan, China recently (Huang et al., 2019). To our knowledge, this is the first report of L. theobromae causing postharvest fruit rot on passion fruit in the Chinese mainland.

5.
Int J Mol Sci ; 21(2)2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31936451

RESUMEN

To clarify the genetic mechanism underlying grain protein content (GPC) and to improve rice grain qualities, the mapping and cloning of quantitative trait loci (QTLs) controlling the natural variation of GPC are very important. Based on genotyping-by-resequencing, a total of 14 QTLs were detected with the Huanghuazhan/Jizi1560 (HHZ/JZ1560) recombinant inbred line (RIL) population in 2016 and 2017. Seven of the fourteen QTLs were repeatedly identified across two years. Using three residual heterozygote-derived populations, a stably inherited QTL named as qGPC1-1 was validated and delimited to a ~862 kb marker interval JD1006-JD1075 on the short arm of chromosome 1. Comparing the GPC values of the RIL population determined by near infrared reflectance spectroscopy (NIRS) and Kjeldahl nitrogen determination (KND) methods, high correlation coefficients (0.966 and 0.983) were observed in 2016 and 2017. Furthermore, 12 of the 14 QTLs were identically identified with the GPC measured by the two methods. These results indicated that instead of the traditional KND method, the rapid and easy-to-operate NIRS was suitable for analyzing a massive number of samples in mapping and cloning QTLs for GPC. Using the gel-based low-density map consisted of 208 simple sequence repeat (SSR) and insert/deletion (InDel) markers, the same number of QTLs (fourteen) were identified in the same HHZ/JZ1560 RIL population, and three QTLs were repeatedly detected across two years. More stably expressed QTLs were identified based on the genome resequencing, which might be attributed to the high-density map, increasing the detection power of minor QTLs. Our results are helpful in dissecting the genetic basis of GPC and improving rice grain qualities through molecular assisted selection.


Asunto(s)
Genoma de Planta , Técnicas de Genotipaje , Proteínas de Granos/metabolismo , Oryza/genética , Sitios de Carácter Cuantitativo/genética , Análisis de Secuencia de ADN , Mapeo Cromosómico , Cruzamientos Genéticos , Ligamiento Genético , Heterocigoto , Endogamia , Fenotipo , Reproducibilidad de los Resultados
6.
J Neurosci ; 38(7): 1756-1773, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29335353

RESUMEN

Potassium voltage-gated channel interacting protein 3 (KChIP3), also termed downstream regulatory element antagonist modulator (DREAM) and calsenilin, is a multifunctional protein belonging to the neuronal calcium sensor (NCS) family. Recent studies revealed the expression of KChIP3 in dorsal root ganglion (DRG) neurons, suggesting the potential role of KChIP3 in peripheral sensory processing. Herein, we show that KChIP3 colocalizes with transient receptor potential ion channel V1 (TRPV1), a critical molecule involved in peripheral sensitization during inflammatory pain. Furthermore, the N-terminal 31-50 fragment of KChIP3 is capable of binding both the intracellular N and C termini of TRPV1, which substantially decreases the surface localization of TRPV1 and the subsequent Ca2+ influx through the channel. Importantly, intrathecal administration of the transmembrane peptide transactivator of transcription (TAT)-31-50 remarkably reduces Ca2+ influx via TRPV1 in DRG neurons and alleviates thermal hyperalgesia and gait alterations in a complete Freund's adjuvant-induced inflammatory pain model in male rats. Moreover, intraplantar injection of TAT-31-50 attenuated the capsaicin-evoked spontaneous pain behavior and thermal hyperalgesia, which further strengthened the regulatory role of TAT-31-50 on TRPV1 channel. In addition, TAT-31-50 could also alleviate inflammatory thermal hyperalgesia in kcnip3-/- rats generated in our study, suggesting that the analgesic effect mediated by TAT-31-50 is independent of endogenous KChIP3. Our study reveals a novel peripheral mechanism for the analgesic function of KChIP3 and provides a potential analgesic agent, TAT-31-50, for the treatment of inflammatory pain.SIGNIFICANCE STATEMENT Inflammatory pain arising from inflamed or injured tissues significantly compromises the quality of life in patients. This study aims to elucidate the role of peripheral potassium channel interacting protein 3 (KChIP3) in inflammatory pain. Direct interaction of the KChIP3 N-terminal 31-50 fragment with transient receptor potential ion channel V1 (TRPV1) was demonstrated. The KChIP3-TRPV1 interaction reduces the surface localization of TRPV1 and thus alleviates heat hyperalgesia and gait alterations induced by peripheral inflammation. Furthermore, the transmembrane transactivator of transcription (TAT)-31-50 peptide showed analgesic effects on inflammatory hyperalgesia independently of endogenous KChIP3. This work reveals a novel mechanism of peripheral KChIP3 in inflammatory hyperalgesia that is distinct from its classical role as a transcriptional repressor in pain modulation.


Asunto(s)
Hiperalgesia/fisiopatología , Inflamación/fisiopatología , Proteínas de Interacción con los Canales Kv/metabolismo , Canales Catiónicos TRPV/metabolismo , Animales , Señalización del Calcio , Represión Epigenética , Adyuvante de Freund , Marcha , Ganglios Espinales/efectos de los fármacos , Técnicas de Inactivación de Genes , Hiperalgesia/inducido químicamente , Inflamación/inducido químicamente , Inyecciones Espinales , Proteínas de Interacción con los Canales Kv/genética , Masculino , Dimensión del Dolor/efectos de los fármacos , Fragmentos de Péptidos/metabolismo , Unión Proteica , Ratas , Canales Catiónicos TRPV/efectos de los fármacos
7.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3780-3785, 2019 Sep.
Artículo en Zh | MEDLINE | ID: mdl-31602953

RESUMEN

The aim of this paper was to investigate the molecular mechanism of Calculus Bovis Sativus( CBS) in alleviating lipid accumulation in vitro by serum pharmacology. The CBS-containing serum of mice was obtained by serum pharmacology method to evaluate its effect on the proliferation of LO2 hepatocytes. The lipid reducing effects of CBS-containing serum through Nrf2 was evaluated by fructose-induced LO2 hepatocyte steatosis model,nuclear factor erythroid 2 related factor 2( Nrf2) agonist oltipraz combined intervention,cell oil red O staining and intracellular triglyceride( TG) content. The effects of CBS-containing serum on lipid peroxidation and hepatocytes apoptosis were evaluated by reactive oxygen species( ROS) and apoptosis assay,respectively. Real-time quantitative polymerase chain reaction( PCR) was used to detect the relative expression of lipid synthesis-related genes and apoptosis-related genes.RESULTS:: showed that CBS drug-containing serum had no significant effect on LO2 hepatocyte proliferation. As compared with the model group,CBS-containing serum could effectively reduce the formation of lipid droplets in fructose-induced LO2 hepatocytes,significantly reduce intracellular TG and ROS levels,and significantly reduce hepatocyte apoptosis rate( P < 0. 05). As compared with the model group,carbohydrate responsive element binding protein( ChREBP),sterol regulatory element binding protein-1 c( SREBP-1 c),fatty acid synthase( FAS),acetyl-CoA carboxylase 1( ACC1),stearoyl-CoA desaturase 1( SCD1),Bax and caspase-3 mRNA levels were significantly reduced in CBS drug-containing serum treatment group( P<0. 05). All of the above effects could be reversed by oltipraz.In conclusion,CBS-containing serum can significantly inhibit the fructose-induced LO2 liver fat deposition,and the mechanism may be related to reducing intracellular ROS level through the Nrf2 pathway and improving intracellular peroxidation state to reduce apoptosis.


Asunto(s)
Cálculos Biliares/química , Hepatocitos/citología , Suero/química , Animales , Apoptosis , Bovinos , Células Cultivadas , Hígado Graso , Fructosa , Hepatocitos/metabolismo , Metabolismo de los Lípidos , Peroxidación de Lípido , Hígado , Medicina Tradicional China , Ratones , Especies Reactivas de Oxígeno/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Triglicéridos
8.
Environ Sci Technol ; 51(11): 6044-6052, 2017 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-28462990

RESUMEN

Sediment samples from the East China and Yellow seas collected adjacent to continental China were found to have lower δ15N values (expressed as δ15N = [15N:14Nsample/15N:14Nair - 1] × 1000‰; the sediment 15N:14N ratio relative to the air nitrogen 15N:14N ratio). In contrast, the Arctic sediments from the Chukchi Sea, the sampling region furthest from China, showed higher δ15N values (2-3‰ higher than those representing the East China and the Yellow sea sediments). Across the sites sampled, the levels of sediment δ15N increased with increasing distance from China, which is broadly consistent with the decreasing influence of anthropogenic nitrogen (NANTH) resulting from fossil fuel combustion and fertilizer use. We concluded that, of several processes, the input of NANTH appears to be emerging as a new driver of change in the sediment δ15N value in marginal seas adjacent to China. The present results indicate that the effect of NANTH has extended beyond the ocean water column into the deep sedimentary environment, presumably via biological assimilation of NANTH followed by deposition. Further, the findings indicate that NANTH is taking over from the conventional paradigm of nitrate flux from nitrate-rich deep water as the primary driver of biological export production in this region of the Pacific Ocean.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Nitrógeno , Regiones Árticas , China , Océanos y Mares , Océano Pacífico
9.
World J Hepatol ; 16(2): 279-285, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38495276

RESUMEN

BACKGROUND: Hepatic cystic and alveolar echinococcosis coinfections, particularly with concurrent abscesses and sinus tract formation, are extremely rare. This article presents a case of a patient diagnosed with this unique presentation, discussing the typical imaging manifestations of both echinococcosis types and detailing the diagnosis and surgical treatment experience thereof. CASE SUMMARY: A 39-year-old Tibetan woman presented with concurrent hepatic cystic and alveolar echinococcosis, accompanied by abdominal wall abscesses and sinus tract formation. Initial conventional imaging examinations suggested only hepatic cystic echinococcosis, but intraoperative and postoperative pathological examination revealed the coinfection. Following radical resection of the lesions, the patient's condition improved, and she was discharged soon thereafter. Subsequent outpatient follow-ups confirmed no recurrence of the hydatid lesion and normal surgical wound healing. Though mixed hepatic cystic and alveolar echinococcosis with abdominal wall abscesses and sinus tract formations are rare, the general treatment approach remains consistent with that of simpler infections of alveolar echinococcosis. CONCLUSION: Lesions involving the abdominal wall and sinus tract formation, may require radical resection. Long-term prognosis includes albendazole and follow-up examinations.

10.
Int J Biol Macromol ; 266(Pt 1): 131106, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38552685

RESUMEN

The process of diabetic wound healing was influenced by the excessive proliferation of reactive oxygen species (ROS). Therefore, in the process of healing diabetic wounds, it was crucial to removing ROS. This study designed composited nanoparticles: KBP, consisted by Konjac glucomannan, bovine serum albumin, and Prussian blue. Then they were embedded in Konjac glucomannan and hydroxypropyl trimethylammonium chloride chitosan composite hydrogel (KH), The KBP@KH hydrogel finally achieved excellent efficacy in diabetic wound healing. The in vitro and in vivo experiments demonstrated that KPB nanoparticles exhibited favorable ROS scavenging capability and biosafety. The KBP@KH hydrogel not only effectively eliminated ROS from diabetic wounds, but also exhibited excellent wound adaptability. The KBP@KH hydrogel facilitated angiogenesis and suppressed the production of inflammatory factors. Overall, the KBP@KH hydrogel dressing was characterized by its user-friendly nature, safety, and high efficiency.


Asunto(s)
Antioxidantes , Diabetes Mellitus Experimental , Ferrocianuros , Hidrogeles , Mananos , Nanocompuestos , Especies Reactivas de Oxígeno , Albúmina Sérica Bovina , Cicatrización de Heridas , Animales , Bovinos , Humanos , Masculino , Ratones , Ratas , Antioxidantes/farmacología , Antioxidantes/química , Vendajes , Quitosano/química , Quitosano/análogos & derivados , Quitosano/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Ferrocianuros/química , Ferrocianuros/farmacología , Depuradores de Radicales Libres/farmacología , Depuradores de Radicales Libres/química , Hidrogeles/química , Hidrogeles/farmacología , Mananos/química , Mananos/farmacología , Nanocompuestos/química , Especies Reactivas de Oxígeno/metabolismo , Albúmina Sérica Bovina/química , Cicatrización de Heridas/efectos de los fármacos
11.
Sci Adv ; 9(33): eade2078, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37585519

RESUMEN

Nitrite, an intermediate product of the oxidation of ammonia to nitrate (nitrification), accumulates in upper oceans, forming the primary nitrite maximum (PNM). Nitrite concentrations in the PNM are relatively low in the western North Pacific subtropical gyre (wNPSG), where eddies are frequent and intense. To explain these low nitrite concentrations, we investigated nitrification in cyclonic eddies in the wNPSG. We detected relatively low half-saturation constants (i.e., high substrate affinities) for ammonia and nitrite oxidation at 150 to 200 meter water depth. Eddy-induced displacement of high-affinity nitrifiers and increased substrate supply enhanced ammonia and nitrite oxidation, depleting ambient substrate concentrations in the euphotic zone. Nitrite oxidation is more strongly enhanced by the cyclonic eddies than ammonia oxidation, reducing concentrations and accelerating the turnover of nitrite in the PNM. These findings demonstrate a spatial decoupling of the two steps of nitrification in response to mesoscale processes and provide insights into physical-ecological controls on the PNM.

12.
Sci Immunol ; 8(87): eabq2424, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37738362

RESUMEN

Metabolic fitness of T cells is essential for their vitality, which is largely dependent on the behavior of the mitochondria. The nature of mitochondrial behavior in tumor-infiltrating T cells remains poorly understood. In this study, we show that mitofusin-2 (MFN2) expression is positively correlated with the prognosis of multiple cancers. Genetic ablation of Mfn2 in CD8+ T cells dampens mitochondrial metabolism and function and promotes tumor progression. In tumor-infiltrating CD8+ T cells, MFN2 enhances mitochondria-endoplasmic reticulum (ER) contact by interacting with ER-embedded Ca2+-ATPase SERCA2, facilitating the mitochondrial Ca2+ influx required for efficient mitochondrial metabolism. MFN2 stimulates the ER Ca2+ retrieval activity of SERCA2, thereby preventing excessive mitochondrial Ca2+ accumulation and apoptosis. Elevating mitochondria-ER contact by increasing MFN2 in CD8+ T cells improves the efficacy of cancer immunotherapy. Thus, we reveal a tethering-and-buffering mechanism of organelle cross-talk that regulates the metabolic fitness of tumor-infiltrating CD8+ T cells and highlights the therapeutic potential of enhancing MFN2 expression to optimize T cell function.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Humanos , Apoptosis , Retículo Endoplásmico , GTP Fosfohidrolasas , Mitocondrias , Proteínas Mitocondriales
13.
Sci Total Environ ; 818: 151678, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-34793800

RESUMEN

Information on the sources and transformations of particulate organic N (PN) and dissolved organic N (DON) at the coastal interface remains insufficient due to technological difficulties and complicated features of intensive physical mixing and rapid biological activities. Here, we investigated the spatial distribution of concentrations and isotopic compositions of PN and DON in the Changjiang plume during the summer flood period. In average, DON and PN accounted for 25.6 ± 12.1% and 8.1 ± 9.1% (n = 55), respectively, of the total N pool, with the remaining N primarily in the form of nitrate (NO3-). Mean δ15N values were the lowest for DON (-0.1 ± 2.7‰, n = 58) and slightly higher for PN (2.0 ± 1.6‰, n = 101), and the highest for NO3- (6.5 ± 2.2‰, n = 67), suggesting multiple transformations had occurred to differentiate isotopic characteristics among the three N pools. By applying a conservative mixing model, we found DON deficits (-3.5 ± 3.7 µmol L-1, n = 43) and negative shift in δ15NDON (-3.6 ± 2.2‰, n = 43) in the Changjiang plume, revealing nonconservative DON behaviors. In the offshore surface plume where Chlorophyll a was high, the most likely cause is the DON uptake by phytoplankton with a strong inverse isotope effect (around -40‰). This DON assimilation by phytoplankton contributed to ~16 ± 12% of the PN production, with the remaining supported by NO3- assimilation, producing an overall isotope effect of 4-9‰. However, in waters near the river mouth and at the bottom of the offshore plume where total suspended matter concentrations were high (>5 mg L-1), the DON deficit was most likely induced by the selective adsorption of 15N enriched moieties of DON onto particulate surfaces (with an isotope effect of -20‰ to -5‰). Unlike dissolved organic carbon to behave conservatively in most estuaries, our results show that active transformations had occurred between the DON and PN pools in the Changjiang plume.


Asunto(s)
Monitoreo del Ambiente , Nitrógeno , China , Clorofila A , Monitoreo del Ambiente/métodos , Nitrógeno/análisis , Isótopos de Nitrógeno/análisis , Ríos
14.
Medicine (Baltimore) ; 101(51): e32291, 2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36595756

RESUMEN

RATIONALE: Hepatic cystic echinococcosis (CE) is a common zoonotic parasitic disease caused by the entry of Echinococcus granulosus eggs into human body. Surgical resection is the optimal treatment choice for hepatic CE. However, Coexistence of CE and hepatocellular carcinoma (HCC) have been reported with a rare incidence rate, which led to unsatisfactory prognosis after the operation. PATIENT CONCERNS: A 69-year-old male patient was admitted to hospital because of "Upper abdominal pain and discomfort for more than 1 month and an aggravation for 10 days." DIAGNOSIS: An elderly male herder who was initially diagnosed as hepatic CE, and none of the preoperative imaging test revealed the existence of HCC. Co-existence of hepatic CE and HCC was confirmed by the postoperative pathological examination. INTERVENTIONS: The patient underwent "combined hepatic segmental resection, portal vein thrombectomy, portal vein repairment, hepatic hydatid internal capsule removal and external subtotal resection, cholecystectomy". OUTCOMES: During follow-up after discharge, the patient did not regularly review and get further treatment and died 8 months after operation. LESSONS: May improve the clinicians' understanding of CE complicated with HCC, and reduce the misdiagnosis of similar case, as well as provide guidance for clinical treatment.


Asunto(s)
Carcinoma Hepatocelular , Equinococosis Hepática , Equinococosis , Neoplasias Hepáticas , Masculino , Humanos , Anciano , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/cirugía , Equinococosis/complicaciones , Equinococosis/diagnóstico , Equinococosis/cirugía , Equinococosis Hepática/complicaciones , Equinococosis Hepática/diagnóstico , Equinococosis Hepática/cirugía , Errores Diagnósticos
15.
J Orthop Surg Res ; 17(1): 560, 2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36550563

RESUMEN

BACKGROUND: Two relatively common forms of injury exist in the posterior cruciate ligament (PCL) after the onset of trauma: PCL tear and tibial avulsion fracture. The mechanism for the occurrence of these different forms of injury is not known. Herein, we aimed to investigate this mechanism by comparing the intercondylar notch parameters between patients with PCL tears and those with PCL avulsion fractures of the tibial insertion. METHODS: Fifty-three patients with PCL tears (37 male, 16 female: median age of 37 years: range 18-54 years) and 46 patients with avulsion fractures of tibial insertion (33 male, 13 female: median age of 33 years: range 18-55 years) were included in this study. Three-dimensional computed tomography (CT) was applied to measure the intercondylar notch width index and intercondylar notch volume. The intercondylar notch volume was simulated as the truncated-pyramid shape. Measurements of the top and bottom areas of this model were conducted on the slice containing the most proximal (S1) and most distal (S2) levels of Blumensaat's line. Femoral condyle height (h) was defined as the vertical distance between two parallel planes, and the volume was calculated as h(S1 + S2 + √(S1S2))/3. The values of S1, S2, h, notch volume, the body mass index (BMI), intercondylar notch width (NW), femoral condylar width (FW) and notch width index (NWI) were compared among the PCL tear and avulsion-fracture groups. RESULTS: The results show a significant difference in the S2 and normalized intercondylar notch volumes among patients with PCL tears and tibial avulsion injuries. Patients with PCL tears have smaller S2 and intercondylar notch volumes than those with tibial avulsion. There were no significant differences between the two groups in S1 or the 2D notch measurement parameters, such as the NW, FW and NWI. In addition, logistic regression analysis revealed notch volume and body mass index (BMI) as two significant independent predictors for PCL tears. CONCLUSION: Decreased intercondylar notch volume and increased BMI are associated with an increased incidence of PCL tears. The occurrence of PCL tears and tibial avulsion injuries is influenced by the femoral intercondylar notch volume, and the measurement of the notch volume could be useful for identifying patients at risk for PCL tears.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Fracturas por Avulsión , Traumatismos de la Rodilla , Ligamento Cruzado Posterior , Traumatismos de los Tejidos Blandos , Esguinces y Distensiones , Fracturas de la Tibia , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Ligamento Cruzado Posterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/complicaciones , Imagen por Resonancia Magnética/métodos , Articulación de la Rodilla , Traumatismos de la Rodilla/diagnóstico por imagen , Fémur , Tomografía Computarizada por Rayos X , Esguinces y Distensiones/complicaciones , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/complicaciones
16.
Wideochir Inne Tech Maloinwazyjne ; 17(3): 406-417, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36187069

RESUMEN

Introduction: There still exist controversies about the advantages and disadvantages of laparoscopic and traditional open surgery. Aim: This meta-analysis aimed to compare the efficacy and safety of laparoscopic versus traditional laparotomy in hepatic cystic hydatidosis. Material and methods: A systematic literature search was conducted for studies about liver hydatid surgery. After the quality assessment and relevant data extraction, the article was screened and included according to the inclusion and exclusion criteria. Meta-analysis was performed using RevMan 5.3 software. Results: Thirteen studies included 1211 cases, 362 in the laparoscopic group, and 849 in the open surgery group. According to meta-analysis, laparoscopic surgery is superior to traditional open surgery in terms of length of hospital stay, the recovery time of gastrointestinal function, total complications, and the risk of incision infection. There were no significant differences between laparoscopic surgery and traditional open surgery in operation time, postoperative time of abdominal drainage tube removal, recurrence rate, bile leakage rate, biliary fistula rate, and residual cavity infection rate. Conclusions: Laparoscopy is superior to traditional open surgery in terms of length of hospital stay, the recovery time of gastrointestinal function, total complications, and the risk of incision infection. There was no significant difference in postoperative recurrence between laparoscopy and open surgery. In addition, we think laparoscopy can achieve the same clinical effect as laparotomy. However, the reliability and validity of our conclusion need to be verified by more randomized controlled trials (RCTs).

17.
Sci Total Environ ; 827: 154042, 2022 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-35217039

RESUMEN

Coastal oceans, known as the major nitrous oxide (N2O) source to the atmosphere, are increasingly subject to eutrophication and concurrent near-bottom hypoxia. The natural nitrogen cycle is likely to be altered markedly in hypoxic coastal oceans. However, the processes responsible for N2O production and emission remain elusive because of lacking field rate measurements simultaneously conducted in the water column and sediment. Here, we quantified N2O production rates using a 15N-labeled technique in the water-column and surface sediments off the Changjiang (Yangtze) River estuary, the largest hypoxic zone in the Pacific margins. Our results showed that the estuarine surface sediments were the major source for N2O production, accounting for approximately 90% of the total water-column accumulation and consequent efflux of N2O in the hypoxic zone, whereas the water-column nitrification and denitrification combined only contributed <10%. More importantly, the coupling of nitrification and denitrification at the presence of abundant supply and remineralization of labile organic matter was the main driver of the N2O release from the sediment-water interface in this region. This study highlights the dominant role of benthic processes occurring at the sediment-water interface controlling the coastal N2O budget, as the anthropogenic eutrophication and hypoxia are expanding in coastal oceans.


Asunto(s)
Óxido Nitroso , Ríos , Desnitrificación , Estuarios , Humanos , Hipoxia , Nitrificación , Nitrógeno/análisis , Óxido Nitroso/análisis , Agua
18.
Pharmacol Rep ; 73(5): 1230-1239, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33595821

RESUMEN

Baicalin is the main active component of Scutellaria baicalensis, widely used in traditional Chinese medicine thanks to its various pharmacological effects, such as anti-tumor, anti-inflammatory, and antibacterial properties, as well as cardiovascular, hepatic, and renal protective effect. Recently, the protective effects of baicalin on liver disease have received much more attention. Several studies showed that baicalin protects against several types of liver diseases including viral hepatitis, fatty liver disease, xenobiotic induced liver injury, cholestatic liver injury, and hepatocellular carcinoma, with a variety of pharmacological mechanisms. A comprehensive understanding of the mechanism of baicalin can provide a valuable reference for its clinical use, but up to now, no narrative review is available that summarizes the pharmacological effects of baicalin to clarify its potential use in the treatment of liver diseases. Therefore, this review summarizes the progress of baicalin research and the underlying mechanism in the treatment of various liver diseases, to promote further research and its clinical application.


Asunto(s)
Flavonoides/farmacología , Flavonoides/uso terapéutico , Hepatopatías/tratamiento farmacológico , Antiinflamatorios no Esteroideos/farmacología , Medicamentos Herbarios Chinos , Humanos
19.
RSC Adv ; 11(11): 6173-6181, 2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35423147

RESUMEN

A new spherical cellulose-based adsorbent and high phosphate removal rate microcrystalline cellulose-g-acrylamide/ethylenediamine/phthalic anhydride (MCC-g-AM/EDA/PA) loaded Fe(iii) adsorbent was prepared by a pre-radiation grafting and chemical modification method. Fe(iii) was successfully introduced into the modified grafted chains of the MCC-g-AM/EDA/PA resin, and characterized by FTIR, TG, XRD, SEM and XPS. The optimized conditions for the grafting reaction of acrylamide (AM) onto MCC were 20% AM emulsion at an absorbed dose of 30 kGy, and a grafting rate as high as 247%. In addition, the adsorption performance of the adsorbent was tested by static adsorption experiments with phosphate. The adsorbent resin showed excellent adsorption performance under alkaline conditions, contributions to the synergetic effect of precipitation, and inner-sphere surface complex reactions. The adsorption efficiency can reach 89.7% at low concentration. In summary, the neotype spherical cellulose-based adsorbent has the advantages of being separation-free in bulk materials, avoiding secondary pollution, and being easy to recycle, and it could be employed as an environmentally friendly adsorbent for phosphate removal in eutrophic water.

20.
Mol Biol Rep ; 37(4): 2099-103, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19680788

RESUMEN

Isolation of high quality RNA from ramie (Boehmeria nivea L. Gaud.) is difficult due to its high levels of polyphenols, polysaccharides, pectin, fat, wax and other secondary metabolites. A modified procedure based on guanidinium isothiocyanate for RNA preparation of ramie was developed in this study. High concentrations (5%, v/v) of guanidinium isothiocyanate, PVP-4000, sodium citrate and sodium lauryl sarcosinate and beta-mercaptoethanol were used in the extraction buffer, together with a low pH sodium acetate (pH 4.0) added to improve the RNA quality. The average yield was about 400 microg RNAg(-1) fresh leaves. One SSH library which was induced by ramie anthracnose was constructed by utilizing the RNA extracted through the present method. These results showed that our protocol was applicable for RNA isolation from recalcitrant ramie tissues.


Asunto(s)
Boehmeria/genética , Biblioteca de Genes , Hibridación de Ácido Nucleico/métodos , ARN de Planta/aislamiento & purificación , ARN de Planta/normas , Northern Blotting , Boehmeria/microbiología , Células Clonales , Colletotrichum/fisiología , Electroforesis en Gel de Agar , Espectrofotometría
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