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1.
Exp Cell Res ; 435(2): 113932, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38246397

RESUMEN

RNA binding protein RBM10 participates in various RNA metabolism, and its decreased expression or loss of function by mutation has been identified in many human cancers. However, how its dysregulation contributes to human cancer pathogenesis remains to be determined. Here, we found that RBM10 expression was decreased in breast tumors, and breast cancer patients with low RBM10 expression presented poorer survival rates. RBM10 depletion in breast cancer cells significantly promotes the cellular proliferation and migration. We further demonstrated that RBM10 forms a triple complex with YBX1 and phosphatase 1B (PPM1B), in which PPM1B serves as the phosphatase of YBX1. RBM10 knock-down markedly attenuated association between YBX1 and PPM1B, leading to elevated levels of YBX1 phosphorylation and its nuclear translocation. Furthermore, cancer cells with RBM10 depletion had a significantly accelerated tumor growth in nude mice. Importantly, these enhanced tumorigenic phenotypes can be reversed by overexpression of PPM1B. Our findings provide the mechanistic bases for functional loss of RBM10 in promoting tumorigenicity, and are potentially useful in the development of combined therapeutic strategies for cancer patients with defective RBM10.


Asunto(s)
Neoplasias de la Mama , Carcinogénesis , Animales , Ratones , Humanos , Femenino , Ratones Desnudos , Carcinogénesis/genética , Fosforilación , Proliferación Celular/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Monoéster Fosfórico Hidrolasas/genética , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Proteína 1 de Unión a la Caja Y/genética , Proteína 1 de Unión a la Caja Y/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteína Fosfatasa 2C/genética , Proteína Fosfatasa 2C/metabolismo
2.
J Am Chem Soc ; 145(8): 4545-4552, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36794794

RESUMEN

On-surface acetylenic homocoupling has been proposed to construct carbon nanostructures featuring sp hybridization. However, the efficiency of linear acetylenic coupling is far from satisfactory, often resulting in undesired enyne products or cyclotrimerization products due to the lack of strategies to enhance chemical selectivity. Herein, we inspect the acetylenic homocoupling reaction of polarized terminal alkynes (TAs) on Au(111) with bond-resolved scanning probe microscopy. The replacement of benzene with pyridine moieties significantly prohibits the cyclotrimerization pathway and facilitates the linear coupling to produce well-aligned N-doped graphdiyne nanowires. Combined with density functional theory calculations, we reveal that the pyridinic nitrogen modification substantially differentiates the coupling motifs at the initial C-C coupling stage (head-to-head vs head-to-tail), which is decisive for the preference of linear coupling over cyclotrimerization.

3.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36768756

RESUMEN

Understanding the genetic mechanisms underlying milk production traits contribute to improving the production potential of dairy animals. Squalene epoxidase (SQLE) is one of the rate-limiting enzymes for cholesterol biosynthesis and was highly expressed in the buffalo mammary. The objectives of the present study were to detect the polymorphisms within SQLE in buffalo, the genetic effects of these mutations on milk production traits, and to understand the gene regulatory effects on buffalo mammary epithelial cells (BuMECs). A total of five SNPs were identified by sequencing, g.18858G > A loci were significantly associated with fat yield, and g.22834C > T loci were significantly associated with peak milk yield, milk yield, fat yield, and protein yield. Notably, linkage disequilibrium analysis indicated that 2 SNPs (g.18858G > A and g.22834C > T) formed one haplotype block, which was found to be significantly associated with milk fat yield, fat percentage, and protein yield. Furthermore, expression of SQLE was measured in different tissues of buffalo and was found to be higher in the mammary. Knockdown of SQLE gene expression significantly affected the growth of BuMECs, including proliferation, cell cycle, and apoptosis, and significantly downregulated the expression of related genes MYC, PCNA, and P21. In addition, knockdown of the SQLE gene significantly reduces triglyceride concentrations and the signal intensity of oil red O staining. In addition, silencing of SQLE was also found to regulate the synthesis and secretion of ß-casein and κ-casein negatively. Furthermore, SQLE knockdown is accompanied by the downregulation of critical genes (RPS6KB1, JAK2, eIF4E, and SREBP1) related to milk fat and protein synthesis. The current study showed the potential of the SQLE gene as a candidate for buffalo milk production traits. It provides a new understanding of the physiological mechanisms underlying buffalo milk production regulation.


Asunto(s)
Leche , Escualeno-Monooxigenasa , Animales , Leche/metabolismo , Escualeno-Monooxigenasa/genética , Escualeno-Monooxigenasa/metabolismo , Fenotipo , Haplotipos , Polimorfismo de Nucleótido Simple , Búfalos/genética
4.
Angew Chem Int Ed Engl ; 62(19): e202218211, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-36857418

RESUMEN

Bicyclo[1.1.1]pentane (BCP) motifs are of growing importance to the pharmaceutical industry as sp3 -rich bioisosteres of benzene rings and as molecular building blocks in materials science. Herein we explore the behavior of 1,3-disubstituted BCP moieties on metal surfaces by combining low-temperature scanning tunneling microscopy / non-contact atomic force microscopy studies with density functional theory modeling. We examine the configuration of individual BCP-containing precursors on Au(111), their supramolecular assembly and thermally activated dehalogenative coupling reactions, affording polymeric chains with incorporated electronically isolating units. Our studies not only provide the first sub-molecular insights of the BCP scaffold behavior on surfaces, but also extend the potential application of BCP derivatives towards integration in custom-designed surface architectures.

5.
J Am Chem Soc ; 144(18): 8214-8222, 2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35442656

RESUMEN

Assembly of semiconducting organic molecules with multiple aryl-metal covalent bonds into stable one- and two-dimensional (1D and 2D) metal-organic frameworks represents a promising route to the integration of single-molecule electronics in terms of structural robustness and charge transport efficiency. Although various metastable organometallic frameworks have been constructed by the extensive use of single aryl-metal bonds, it remains a great challenge to embed multiple aryl-metal bonds into these structures due to inadequate knowledge of harnessing such complex bonding motifs. Here, we demonstrate the substrate-modulated synthesis of 1D and 2D metal-organic hybrids (MOHs) with the organic building blocks (perylene) interlinked solely with multiple aryl-metal bonds via the stepwise thermal dehalogenation of 3,4,9,10-tetrabromo-1,6,7,12-tetrachloroperylene and subsequent metal-organic connection on metal surfaces. More importantly, the conversion from 1D to 2D MOHs is completely impeded on Au(111) but dominant on Ag(111). We comprehensively study the distinct reaction pathways on the two surfaces by visually tracking the structural evolution of the MOHs with high-resolution scanning tunneling and noncontact atomic force microscopy, supported by first-principles density functional theory calculations. The substrate-dependent structural control of the MOHs is attributed to the variation of the M-X (M = Au, Ag; X = C, Cl) bond strength regulated by the nature of the metal species.

6.
J Am Chem Soc ; 144(47): 21596-21605, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36383110

RESUMEN

On-surface synthesis is a powerful methodology for the fabrication of low-dimensional functional materials. The precursor molecules usually anchor on different metal surfaces via similar configurations. The activation energies are therefore solely determined by the chemical activity of the respective metal surfaces. Here, we studied the influence of the detailed adsorption configuration on the activation energy on different metal surfaces. We systematically studied the desulfonylation homocoupling for a molecular precursor on Au(111) and Ag(111) and found that the activation energy is lower on inert Au(111) than on Ag(111). Combining scanning tunneling microscopy observations, synchrotron radiation photoemission spectroscopy measurements, and density functional theory calculations, we elucidate that the phenomenon arises from different molecule-substrate interactions. The molecular precursors anchor on Au(111) via Au-S interactions, which lead to weakening of the phenyl-S bonds. On the other hand, the molecular precursors anchor on Ag(111) via Ag-O interactions, resulting in the lifting of the S atoms. As a consequence, the activation barrier of the desulfonylation reactions is higher on Ag(111), although silver is generally more chemically active than gold. Our study not only reports a new type of on-surface chemical reaction but also clarifies the influence of detailed adsorption configurations on specific on-surface chemical reactions.


Asunto(s)
Oro , Plata , Oro/química , Plata/química , Conformación Molecular , Adsorción
7.
Angew Chem Int Ed Engl ; 61(5): e202113590, 2022 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-34708485

RESUMEN

Amide bond formation is one of the most important reactions in biochemistry, notably being of crucial importance for the origin of life. Herein, we combine scanning tunneling microscopy and X-ray photoelectron spectroscopy studies to provide evidence for thermally activated abiotic formation of amide bonds between adsorbed precursors through direct carboxyl-amine coupling under ultrahigh-vacuum conditions by means of on-surface synthesis. Complementary insights from temperature-programmed desorption measurements and density functional theory calculations reveal the competition between cross-coupling amide formation and decarboxylation reactions on the Au(111) surface. Furthermore, we demonstrate the critical influence of the employed metal support: whereas on Au(111) the coupling readily occurs, different reaction scenarios prevail on Ag(111) and Cu(111). The systematic experiments signal that archetypical bio-related molecules can be abiotically synthesized in clean environments without water or oxygen.

8.
Angew Chem Int Ed Engl ; 61(30): e202204123, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35474405

RESUMEN

We describe the on-surface dehalogenative homocoupling of benzylic bromides, namely bis-bromomethyl- and bis-gem-(dibromomethyl) naphthalene as a potential route to either hydrocarbon dimers or conjugated polymers on Au(111). While bis-gem-(dibromomethyl) naphthalene affords different dimers with naphthocyclobutadiene as the key intermediate, bis-bromomethyl naphthalene furnishes a poly(o-naphthylene vinylidene) as a non-conjugated polymer which undergoes dehydrogenation toward its conjugated derivative poly(o-naphthylene vinylene) upon mild annealing. A combination of scanning tunneling microscopy, non-contact atomic force microscopy and density functional theory calculations provides deep insights into the prevailing mechanisms.

9.
Molecules ; 26(23)2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34885671

RESUMEN

Endometritis is the inflammatory response of the endometrial lining of the uterus and is associated with low conception rates, early embryonic mortality, and prolonged inter-calving intervals, and thus poses huge economic losses to the dairy industry worldwide. Ginsenoside Rb1 (GnRb1) is a natural compound obtained from the roots of Panax ginseng, having several pharmacological and biological properties. However, the anti-inflammatory properties of GnRb1 in lipopolysaccharide (LPS)-challenged endometritis through the TLR4-mediated NF-κB signaling pathway has not yet been researched. This study was planned to evaluate the mechanisms of how GnRb1 rescues LPS-induced endometritis. In the present research, histopathological findings revealed that GnRb1 ameliorated LPS-triggered uterine injury. The ELISA and RT-qPCR assay findings indicated that GnRb1 suppressed the expression level of pro-inflammatory molecules (TNF-α, IL-1ß and IL-6) and boosted the level of anti-inflammatory (IL-10) cytokine. Furthermore, the molecular study suggested that GnRb1 attenuated TLR4-mediated NF-κB signaling. The results demonstrated the therapeutic efficacy of GnRb1 in the mouse model of LPS-triggered endometritis via the inhibition of the TLR4-associated NF-κB pathway. Taken together, this study provides a baseline for the protective effect of GnRb1 to treat endometritis in both humans and animals.


Asunto(s)
Antiinflamatorios/administración & dosificación , Endometritis/inducido químicamente , Endometritis/tratamiento farmacológico , Ginsenósidos/administración & dosificación , Lipopolisacáridos/efectos adversos , FN-kappa B/metabolismo , Panax/química , Fitoquímicos/administración & dosificación , Fitoterapia/métodos , Extractos Vegetales/administración & dosificación , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Animales , Citocinas/metabolismo , Endometritis/metabolismo , Femenino , Ratones , Ratones Endogámicos BALB C , Resultado del Tratamiento
10.
Phys Chem Chem Phys ; 22(33): 18622-18630, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32789324

RESUMEN

C-H activation of light alkanes is one of the most important reactions for a plethora of applications but requires catalysts to operate at feasible conditions. MXenes, a new group of two-dimensional materials, have shown great promise as heterogeneous catalysts for several applications. However, the catalytic activity of MXenes depends on the type and distribution of termination groups. Theoretically, it is desired to search for a relation between the catalytic activity and the termination configuration by employing a simple descriptor in order to avoid tedious activation energy calculations. Here, we show that MXenes are promising for splitting C-H bonds of light alkanes. Furthermore, we present how a quantitative descriptor - the hydrogen affinity - can be used to characterize the termination configuration of Ti2CTz (T = O, OH) MXenes, as well as the catalytic activity towards dehydrogenation reactions, using propane as model system. First-principles calculations reveal that the hydrogen affinity can be considered as an intrinsic property of O and OH terminated Ti2C MXenes, in which the mean hydrogen affinity for the terminated Ti2C MXenes is linearly correlated to the statistical average of their OH fraction. In addition, the C-H activation energies exhibit a strong scaling relationship to the hydrogen affinity. This quantity can therefore yield quick predictions of catalytic activity of terminated Ti2C MXenes towards C-H activations, and even predict their chemical selectivity toward scissoring different C-H bonds. We believe that the hydrogen affinity will accelerate the discovery of further applications of the broad family of MXenes in heterogeneous catalysis.

11.
J Am Chem Soc ; 141(18): 7399-7406, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31016976

RESUMEN

Controlling the regioselectivity of C-H activation in unimolecular reactions is of great significance for the rational synthesis of functional graphene nanostructures, which are called nanographenes. Here, we demonstrate that the adsorption of tetranaphthyl- p-terphenyl precursors on metal surfaces can completely change the cyclodehydrogenation route and lead to obtaining planar benzo-fused perihexacenes rather than double [7]helicenes during solution synthesis. The course of the on-surface planarization reactions is monitored using scanning probe microscopy, which unambiguously reveals the formation of dibenzoperihexacenes and the structures of reaction intermediates. The regioselective planarization can be attributed to the flattened adsorption geometries and the reduced flexibility of the precursors on the surfaces, in addition to the different mechanism of the on-surface cyclodehydrogenation from that of the solution counterpart. We have further achieved the on-surface synthesis of dibenzoperioctacene by employing a tetra-anthryl- p-terphenyl precursor. The energy gaps of the new nanographenes are measured to be approximately 2.1 eV (dibenzoperihexacene) and 1.3 eV (dibenzoperioctacene) on a Au(111) surface. Our findings shed new light on the regioselectivity in cyclodehydrogenation reactions, which will be important for exploring the synthesis of unprecedented nanographenes.

12.
Biochem Cell Biol ; 96(1): 44-49, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29035693

RESUMEN

MMS19 localizes to the cytoplasmic and nuclear compartments involved in transcription and nucleotide excision repair (NER). However, whether MMS19 localizes to mitochondria, where it plays a role in maintaining mitochondrial genome stability, remains unknown. In this study, we provide the first evidence that MMS19 is localized in the inner membrane of mitochondria and participates in mtDNA oxidative damage repair. MMS19 knockdown led to mitochondrial dysfunctions including decreased mtDNA copy number, diminished mtDNA repair capacity, and elevated levels of mtDNA common deletion after oxidative stress. Immunoprecipitation - mass spectrometry analysis identified that MMS19 interacts with ANT2, a protein associated with mitochondrial ATP metabolism. ANT2 knockdown also resulted in a decreased mtDNA repair capacity after oxidative damage. Our findings suggest that MMS19 plays an essential role in maintaining mitochondrial genome stability.


Asunto(s)
ADN Mitocondrial/metabolismo , Genoma Mitocondrial/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Estrés Oxidativo , Factores de Transcripción/metabolismo , Células Cultivadas , ADN Mitocondrial/efectos de los fármacos , Genoma Mitocondrial/efectos de los fármacos , Proteínas del Choque Térmico HSP72/metabolismo , Humanos , Mitocondrias/efectos de los fármacos , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , ARN Interferente Pequeño/farmacología , Factores de Transcripción/antagonistas & inhibidores
13.
Phys Chem Chem Phys ; 20(23): 15901-15906, 2018 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-29850686

RESUMEN

Recently, Au-based nanostructures have attracted extensive interest due to their excellent activities in heterogeneous catalysis. The reaction mechanisms have been interpreted qualitatively by the quantum confinement effect due to the low-coordination of Au atoms in nanostructures. In this work, systematic first-principles calculations were carried out to obtain an in-depth understanding of the origin of C-H bond activations with Au-based catalysts in on-surface synthesis. Combining density functional theory (DFT) calculations and scanning tunneling microscopy (STM) studies, we reveal that the d-band centre and the d-band width of the Au-5dz2 orbital in an energy window of -6.80 to 0.00 eV may serve as theoretical descriptors for the prediction of the activity of Au catalysts in C-H bond activations. This work may therefore inspire further investigations on the design of new catalysts.

14.
Faraday Discuss ; 204: 297-305, 2017 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-28787051

RESUMEN

We report a new pathway to fabricate armchair graphene nanoribbons with five carbon atoms in the cross section (5-AGNRs) on Cu(111) surfaces. Instead of using haloaromatics as precursors, the 5-AGNRs are synthesized via a surface assisted decarboxylation reaction of perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA). The on-surface decarboxylation of PTCDA can produce extended copper-perylene chains on Cu(111) that are able to transform into graphene nanoribbons after annealing at higher temperatures (ca. 630 K). Due to the low yield (ca. 20%) of GNRs upon copper extrusion, various gases are introduced to assist the transformation of the copper-perylene chains into the GNRs. Typical reducing gases (H2 and CO) and oxidizing gas (O2) are evaluated for their performance in breaking aryl-Cu bonds. This method enriches on-surface protocols for the synthesis of AGNRs using non-halogen containing precursors.

15.
Nucleic Acids Res ; 43(11): 5476-88, 2015 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-25969448

RESUMEN

Xeroderma pigmentosum group D (XPD/ERCC2) encodes an ATP-dependent helicase that plays essential roles in both transcription and nucleotide excision repair of nuclear DNA, however, whether or not XPD exerts similar functions in mitochondria remains elusive. In this study, we provide the first evidence that XPD is localized in the inner membrane of mitochondria, and cells under oxidative stress showed an enhanced recruitment of XPD into mitochondrial compartment. Furthermore, mitochondrial reactive oxygen species production and levels of oxidative stress-induced mitochondrial DNA (mtDNA) common deletion were significantly elevated, whereas capacity for oxidative damage repair of mtDNA was markedly reduced in both XPD-suppressed human osteosarcoma (U2OS) cells and XPD-deficient human fibroblasts. Immunoprecipitation-mass spectrometry analysis was used to identify interacting factor(s) with XPD and TUFM, a mitochondrial Tu translation elongation factor was detected to be physically interacted with XPD. Similar to the findings in XPD-deficient cells, mitochondrial common deletion and oxidative damage repair capacity in U2OS cells were found to be significantly altered after TUFM knock-down. Our findings clearly demonstrate that XPD plays crucial role(s) in protecting mitochondrial genome stability by facilitating an efficient repair of oxidative DNA damage in mitochondria.


Asunto(s)
Daño del ADN , Genoma Mitocondrial , Proteínas Mitocondriales/metabolismo , Estrés Oxidativo , Proteína de la Xerodermia Pigmentosa del Grupo D/metabolismo , Línea Celular Tumoral , Reparación del ADN , Silenciador del Gen , Células HEK293 , Humanos , Mitocondrias/metabolismo , Proteínas Mitocondriales/análisis , Proteínas Mitocondriales/antagonistas & inhibidores , Proteínas Mitocondriales/aislamiento & purificación , Proteínas Mitocondriales/fisiología , Factor Tu de Elongación Peptídica/fisiología , Especies Reactivas de Oxígeno/metabolismo , Eliminación de Secuencia , Proteína de la Xerodermia Pigmentosa del Grupo D/análisis , Proteína de la Xerodermia Pigmentosa del Grupo D/antagonistas & inhibidores , Proteína de la Xerodermia Pigmentosa del Grupo D/deficiencia
16.
Front Vet Sci ; 11: 1330693, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38645645

RESUMEN

Bovine tuberculosis (bTB) is a chronic zoonotic disease caused by Mycobacterium bovis. A large number of cattle are infected with bTB every year, resulting in huge economic losses. How to control bTB is an important issue in the current global livestock economy. In this study, the original transcriptome sequences related to this study were obtained from the dataset GSE192537 by searching the Gene Expression Omnibus (GEO) database. Our differential gene analysis showed that there were obvious biological activities related to immune activation and immune regulation in the early stage of bTB. Immune-related biological processes were more active in the early stage of bTB than in the late. There were obvious immune activation and immune cell recruitment in the early stage of bTB. Regulations in immune receptors are associated with pathophysiological processes of the early stage of bTB. A gene module consisting of 236 genes significantly related to the early stage of bTB was obtained by weighted gene co-expression network analysis, and 18 hub genes were further identified as potential biomarkers or therapeutic targets. Finally, by random forest algorithm and logistic regression modeling, FCRL1 was identified as a representative mRNA marker in early bTB blood. FCRL1 has the potential to be a diagnostic biomarker in early bTB.

17.
Nat Commun ; 15(1): 3030, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589464

RESUMEN

On-surface synthesis provides tools to prepare low-dimensional supramolecular structures. Traditionally, reactive radicals are a class of single-electron species, serving as exceptional electron-withdrawing groups. On metal surfaces, however, such species are affected by conduction band screening effects that may even quench their unpaired electron characteristics. As a result, radicals are expected to be less active, and reactions catalyzed by surface-stabilized radicals are rarely reported. Herein, we describe a class of inter-molecular radical transfer reactions on metal surfaces. With the assistance of aryl halide precursors, the coupling of terminal alkynes is steered from non-dehydrogenated to dehydrogenated products, resulting in alkynyl-Ag-alkynyl bonds. Dehalogenated molecules are fully passivated by detached hydrogen atoms. The reaction mechanism is unraveled by various surface-sensitive technologies and density functional theory calculations. Moreover, we reveal the universality of this mechanism on metal surfaces. Our studies enrich the on-surface synthesis toolbox and develop a pathway for producing low-dimensional organic materials.

18.
Animals (Basel) ; 13(5)2023 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-36899699

RESUMEN

Different bedding materials have important effects on the behavioristics, production performance and welfare of buffalo. This study aimed to compare the effects of two bedding materials on lying behavior, production performance and animal welfare of dairy buffaloes. More than 40 multiparous lactating buffaloes were randomly divided into two groups, which were raised on fermented manure bedding (FMB) and chaff bedding (CB). The results showed that the application of FMB improved the lying behavior of buffaloes, the average daily lying time (ADLT) of buffaloes in FMB increased by 58 min compared to those in CB, with a significant difference (p < 0.05); the average daily standing time (ADST) decreased by 30 min, with a significant difference (p < 0.05); and the buffalo comfort index (BCI) increased, but the difference was not significant (p > 0.05). The average daily milk yield of buffaloes in FMB increased by 5.78% compared to buffaloes in CB. The application of FMB improved the hygiene of buffaloes. The locomotion score and hock lesion score were not significantly different between the two groups and all buffaloes did not show moderate and severe lameness. The price of FMB was calculated to be 46% of CB, which greatly reduced the cost of bedding material. In summary, FMB has significantly improved the lying behavior, production performance and welfare of buffaloes and significantly reduce the cost of bedding material.

19.
J Anim Sci ; 1012023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37455295

RESUMEN

Water buffalo milk is a reliable source of high-quality nutrients; however, the susceptibility of mastitis in buffaloes must be taken into consideration. An animal with somatic cell count (SCC) of greater than 250,000 cells/mL is reported to be likely to have mastitis which has serious adverse effects on animal health, reproduction, milk yield, and milk quality. Type traits (TTs) of water buffalo can affect SCC in animal milk to some extent, but few reports on the correlation between SCC and TTs are available. In this study, a total of 1908 records collected from 678 water buffaloes were investigated. The general linear model was used to identify factors associated with phenotypic variation of the somatic cell score (SCS) trait, including parity, lactation length, calving year, and calving season as fixed effects. Using PROC CORR analysis method, taking calving year and lactation length as covariates, the correlation co-efficient between TT and SCS was obtained. Our results showed that correlation co-efficients between the 45 TTs with SCS ranged from 0.003 to 0.443 (degree of correlation). The correlation between udder traits and SCS was greater than that between body structure traits and SCS. Among udder traits, distance between teats (including front and rear teat distance [r = 0.308], front teat distance [r = 0.211], and teat crossing distance [r = 0.412]) and teat circumference (r = 0.443) had the highest correlation with SCS, followed by the leg traits including rear leg height (r = -0.354) and hock bend angle (r = -0.170). Animal with high rear legs (>48 cm) and short teat crossing distance (<17 cm), and narrow teat circumference (<11 cm) exhibited low SCS. Using four nonlinear models (Von Bertalanffy, Brody, Logistic, and Gompertz), the optimal growth curves of the TTs highly correlated with the SCS (rear leg height and teat crossing distance) were fitted, and the correction co-efficients of these two TTs rear leg height and teat crossing distance of animal from young age (2 mo old) to first lactation (35 mo old) were attained for establishment of early selection method for water buffaloes with low SCS. This study provides theoretical support for early selection of low-SCS water buffaloes and lays a foundation for improving milk quality and promoting healthy development of water buffalo's dairy industry.


Some type traits (TTs) have been reported to affect somatic cell count (SCC) in bovine milk, which result in mastitis to some extent, but the correlation between SCC and TTs of water buffalo has been poorly understood. Here, a total of 1908 records from 678 buffaloes were investigated. The correlation between 45 TTs and somatic cell score (SCS) was analysed, and the optimal growth curves of TTs highly correlated with SCS were fitted. Our result showed that high rear legs (>48 cm) and short teat crossing distance (<17 cm), and narrow teat circumference (<11 cm) were correlated with low SCS. We obtained correction co-efficients for two TTs highly correlated with SCS of water buffalos from young age (2 mo old) to first lactation (35 mo) by fitting the optimal growth curve for rear leg height and teat crossing distance. This study provides theoretical support for early selection for water buffaloes that are less susceptible to mastitis, and lays a foundation for improving milk quality and promoting healthy development of water buffalo dairy industry.


Asunto(s)
Búfalos , Mastitis , Embarazo , Femenino , Animales , Glándulas Mamarias Animales , Leche/metabolismo , Lactancia , Recuento de Células/veterinaria , Mastitis/metabolismo , Mastitis/veterinaria
20.
Nanoscale Horiz ; 8(3): 368-376, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36629866

RESUMEN

We have computationally studied the formation mechanism of the biphenylene network via the intermolecular HF zipping, as well as identified key intermediates experimentally, on the Au(111) surface. We elucidate that the zipping process consists of a series of defluorinations, dehydrogenations, and C-C coupling reactions. The Au substrate not only serves as the active site for defluorination and dehydrogenation, but also forms C-Au bonds that stabilize the defluorinated and dehydrogenated phenylene radicals, leading to "standing" benzyne groups. Despite that the C-C coupling between the "standing" benzyne groups is identified as the rate-limiting step, the limiting barrier can be reduced by the adjacent chemisorbed benzyne groups. The theoretically proposed mechanism is further supported by scanning tunneling microscopy experiments, in which the key intermediate state containing chemisorbed benzyne groups can be observed. This study provides a comprehensive understanding towards the on-surface intermolecular HF zipping, anticipated to be instructive for its future applications.

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