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1.
J Struct Biol ; 216(2): 108074, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38432597

RESUMEN

Calcium carbonate is present in many biominerals, including in the exoskeletons of crustaceans and shells of mollusks. High Mg-containing calcium carbonate was synthesized by high temperatures, high pressures or high molecular organic matter. For example, biogenic high Mg-containing calcite is synthesized under strictly controlled Mg concentration at ambient temperature and pressure. The spines of sea urchins consist of calcite, which contain a high percentage of magnesium. In this study, we investigated the factors that increase the magnesium content in calcite from the spines of the sea urchin, Heliocidaris crassispina. X-ray diffraction and inductively coupled plasma mass spectrometry analyses showed that sea urchin spines contain about 4.8% Mg. The organic matrix extracted from the H. crassispina spines induced the crystallization of amorphous phase and synthesis of magnesium-containing calcite, while amorphous was synthesized without SUE (sea urchin extract). In addition, aragonite was synthesized by SUE treated with protease-K. HC tropomyosin was specifically incorporated into Mg precipitates. Recombinant HC-tropomyosin induced calcite contained 0.1-2.5% Mg synthesis. Western blotting of sea urchin spine extracts confirmed that HC tropomyosin was present in the purple sea urchin spines at a protein weight ratio of 1.5%. These results show that HC tropomyosin is one factor that increases the magnesium concentration in the calcite of H. crassispina spines.


Asunto(s)
Carbonato de Calcio , Magnesio , Erizos de Mar , Tropomiosina , Animales , Carbonato de Calcio/química , Carbonato de Calcio/metabolismo , Erizos de Mar/metabolismo , Tropomiosina/química , Tropomiosina/metabolismo , Magnesio/química , Difracción de Rayos X , Cristalización
2.
J Foot Ankle Surg ; 58(6): 1235-1244, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31494029

RESUMEN

The purposes of this study were to integrate the types of interconnecting fibers among components of the chiasma plantare and to deduce their flexion actions. The chiasma plantare and the long flexor tendons in 52 cadaveric feet (26 left feet and 25 right feet) were dissected and removed via gross anatomic dissection. The connections among the flexor digitorum longus (FDL), flexor hallucis longus (FHL), and quadratus plantae (QP) were then classified and analyzed. The connection between the FHL and FDL was type I in 43 (86%) cases, type III in 2 (4%) cases, and type V in 5 (10%) cases, with the FHL manipulating the first through third toes and the FDL manipulating the first through the fifth toes. The shape of the QP in 28 (56%) cases exhibited a 2-headed QP, and in 22 (44%) cases, a medial-headed QP. The composition of the chiasma plantare was 2 layers in 28 (56%) cases and 3 layers in 22 (44%) cases: 9 (18%) cases were type a, 2 (4%) cases were type b1, and 1 (2%) case each was classified as type b2 and b3. The FHL controlled the second toe in 10 (20%) cases; both the second and third toes in 27 (54%) cases; and the second, third, and fourth toes in 13 (26%) cases. The QP manipulated the third and fourth toes in all cases, the second toe in 38 (76%) cases, and the fifth toe in 11 (22%) cases. These data suggest that such variations might result from tendon transfer. In conclusion, we considered the FDL to be more advanced for the recovery of both the ankle and the forefoot based on this study.


Asunto(s)
Pie/anatomía & histología , Tendones/anatomía & histología , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Masculino
3.
J Nat Prod ; 81(1): 78-84, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29303267

RESUMEN

Serpulanines A (1), B (2), and C (3) have been isolated from extracts of the rare Sri Lankan macrofungus Serpula sp. The structures of 1, 2, and 3 were elucidated by a combination of spectroscopic and single-crystal X-ray diffraction analyses. Serpulanines A (1) and B (2) both contain the rare (E)-2-hydroxyimino hydroxamic acid functional group array. A proposed biogenesis for serpulanine B (2) suggests that its (E)-2-hydroxyimino hydroxamic acid moiety arises from a diketopiperazine precursor. Synthetic serpulanine A (1) inhibited class I/II histone deacetylases in murine metastatic lung carcinoma cells with an IC50 of 7 µM.


Asunto(s)
Basidiomycota/química , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Tirosina/análogos & derivados , Tirosina/farmacología , Animales , Línea Celular Tumoral , Cristalografía por Rayos X/métodos , Células HeLa , Inhibidores de Histona Desacetilasas/aislamiento & purificación , Humanos , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Oxidación-Reducción , Tirosina/química , Tirosina/aislamiento & purificación
4.
Mol Cancer ; 16(1): 75, 2017 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-28376832

RESUMEN

BACKGROUND: Early diagnosis of esophageal squamous cell carcinoma (ESCC) is an important issue to improve the prognosis. HOX transcript antisense RNA (HOTAIR), a long noncoding RNA (lncRNA) expressed from the HOXC locus, has been recently revealed as an oncogenic regulator in ESCC. This study aimed to investigate whether serum HOTAIR is involved in the diagnosis of ESCC. METHODS: In this study, we detected serum HOTAIR expression in 50 patients with ESCC (including 42 tumor resection and 8 without surgery) and 20 healthy volunteers to investigate the role of serum HOTAIR in ESCC using the quantitative real-time polymerase chain reaction (qRT-PCR) method. RESULTS: Clinical data indicated that serum HOTAIR were correlated with TNM stage. The expression level of serum HOTAIR (0.189 ± 0.010) was significantly higher in ESCC patients compared with that of healthy controls (0.055 ± 0.008, P < 0.01). The ROC curve analysis yielded an area under the ROC curve (AUC) value of 0.793 (95% CI: 0.692 to 0.895, P < 0.01). Also, the serum HOTAIR expression level decreased obviously in postoperative samples (one month after the surgery) compared to preoperative specimens. Moreover, there was a significant correlation between serum HOTAIR expression and the expression of HOTAIR in ESCC tissue according to Pearson correlation analysis. CONCLUSIONS: Our study, for the first time, demonstrated that serum HOTAIR might serve as a potential biomarker for the diagnosis of ESCC.


Asunto(s)
Biomarcadores de Tumor , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , ARN Largo no Codificante/genética , Adulto , Anciano , Carcinoma de Células Escamosas/sangre , Estudios de Casos y Controles , Neoplasias Esofágicas/sangre , Carcinoma de Células Escamosas de Esófago , Femenino , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , ARN Largo no Codificante/sangre , Curva ROC
5.
Sensors (Basel) ; 15(10): 26643-53, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26492251

RESUMEN

In a surface acoustic wave (SAW) wireless sensor with a reflective delay line structure, three reflectors are often used to eliminate 2π ambiguity of phase measurement. The maximum range of the measured parameter and the maximum accuracy have recently been attracting much research attention. In this paper, an analytical formula for all the factors influencing the measurement range and accuracy of the delay line SAW sensor are deduced for the first time. The factors include: the sensor sensitivity, the topology of the delay line, the available wireless bandwidth and the allowed maximum phase measuring error of the reading system, which is easier to retrieve and more fully describes the possible noises than SNR. Additionally, many designers believe that increasing the reflector could improve accuracy continuously or realize multi-resolution measurement. However, they ignore some certain criteria that the reflector location must satisfy. The reachable maximum accuracy by every increase of a reflector is also presented. A SAW temperature sensor system using 128° YX-LiNbO3 is designed to verify the above theoretical analysis.

6.
Inorg Chem ; 53(6): 3117-25, 2014 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-24592918

RESUMEN

This Paper reports the first examples of O-P-O bridged Mn2(salen)2 (salen = N,N'-bis(salicylidene)ethylenediamine) chain compounds, namely, [Mn2(salen)2(2-FC6H4PO3H)](ClO4)·1/2CH3OH (1) and [Mn2(salen)2(4-FC6H4PO3H)](ClO4) (2). The phosphonate ligands adopt a syn-anti bidentate bridging mode in 1 and a syn-syn bidentate bridging mode in 2, originated from the isomeric phosphonate ligands. The different bridging modes cause a significant change in the Mn-O···O-Mn torsion angle over the O-P-O bridge, which are 96.6 and 1.9° for 1 and 2, respectively. As a result, the antiferromagnetic (AF) exchange couplings mediated through the O-P-O pathway are extremely weak in 1, and the overall magnetic behaviors are dominated by the Mn2(salen)2 moieties. Single-molecule magnetic behavior is observed in 1. For compound 2, the AF interaction over the O-P-O bridge is much stronger. The coexistence of metamagnetism and single-chain magnetic behavior is observed for 2.

7.
Chemosphere ; 336: 139221, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37327822

RESUMEN

Biofilm-based biological nitrification is widely used for ammonia removal, while hasn't been explored for ammonia analysis. The stumbling block is the coexist of nitrifying and heterotrophic microbes in real environment resulting in non-specific sensing. Herein, an exclusive ammonia sensing nitrifying biofilm was screened from natural bioresource, and a bioreaction-detection system for the on-line analysis of environmental ammonia based on biological nitrification was reported. The nitrifying microbes were aggregated into a nitrifying biofilm through a result-oriented bioresource enrichment strategy. The predominant nitrifying population and progressive surface reaction in the plug flow bioreactor led to the exclusive and exhaustive ammonia biodegradation for the establishment of a novel analytical method. The on-line ammonia monitoring prototype achieved complete biodegradation for determining ammonium nitrogen within 5 min and showed exceptional reliability in long-term real sample measurements without frequent calibration. This work offers a low-threshold natural screening paradigm for developing sustainable bioresource-based analytical technologies.


Asunto(s)
Amoníaco , Nitrificación , Amoníaco/metabolismo , Reproducibilidad de los Resultados , Reactores Biológicos , Biopelículas
8.
Sci Rep ; 11(1): 11306, 2021 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-34050239

RESUMEN

The Pacific oyster, Crassostrea gigas, is a traditional food worldwide. The soft body of the oyster can easily accumulate heavy metals such as cadmium (Cd). To clarify the molecular mechanism of Cd accumulation in the viscera of C. gigas, we identified Cd-binding proteins. 5,10,15,20-Tetraphenyl-21H,23H-porphinetetrasulfonic acid, disulfuric acid, tetrahydrate, and Cd-binding competition experiments using immobilized metal ion affinity chromatography revealed the binding of water-soluble high molecular weight proteins to Cd, including C. gigas protein disulfide isomerase (cgPDI). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses revealed two CGHC motifs in cgPDI. The binding between Cd and rcgPDI was confirmed through a Cd-binding experiment using the TPPS method. Isothermal titration calorimetry (ITC) revealed the binding of two Cd ions to one molecule of rcgPDI. Circular dichroism (CD) spectrum and tryptophan fluorescence analyses demonstrated that the rcgPDI bound to Cd. The binding markedly changed the two-dimensional or three-dimensional structures. The activity of rcgPDI measured by a PDI Activity Assay Kit was more affected by the addition of Cd than by human PDI. Immunological analyses indicated that C. gigas contained cgPDI at a concentration of 1.0 nmol/g (viscera wet weight). The combination of ITC and quantification results revealed that Cd-binding to cgPDI accounted for 20% of the total bound Cd in the visceral mass. The findings provide new insights into the defense mechanisms of invertebrates against Cd.


Asunto(s)
Cadmio/análisis , Crassostrea/metabolismo , Metalotioneína/metabolismo , Animales , Cadmio/metabolismo , Cromatografía Liquida/métodos , Branquias/metabolismo , Metalotioneína/aislamiento & purificación , Metalotioneína/fisiología , Mariscos , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/análisis
9.
Dalton Trans ; 45(7): 2974-82, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26754592

RESUMEN

Salen-type mononuclear lanthanide complexes with formula (Et3NH)[Ln(3-NO2-salen)2]·solvent (Ln = Eu (1Eu), Tb (2Tb), Dy (3Dy), Ho (4Ho), Er (5Er), Yb (6Yb); 3-NO2-salen(2-) = N,N'-bis(3-nitro-salicylaldehyde)ethylenediamine dianion) are reported. These compounds are isostructural in which two crystallographically distinct 3-NO2-salen(2-) act as tetradentate ligands encapsulating the lanthanide ions in a meridional mode forming the [LnN4O4] cores. Slow magnetization relaxation processes associated with single ion magnet (SIM) behaviors are observed in complexes 3Dy, 5Er and 6Yb with the Kramer ions but not in 2Tb and 4Ho with non-Kramer ions. Photoluminescence studies reveal that complexes 1Eu, 5Er and 6Yb exhibit characteristic lanthanide luminescence with sharp and well-separated emission bands. Complex 1Eu is of particular interest in which the organic ligand functioning as a powerful absorbing sensitizer apparently broadens the excitation range into 300-500 nm with the maximum of 460 nm.

10.
Dalton Trans ; 45(2): 690-5, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26621766

RESUMEN

A pair of enantiopure mononuclear dysprosium/salen-type complexes (Et3NH)[Dy((R,R)/(S,S)-3-NO2salcy)2] (/), where 3-NO2salcyH2 represents N,N'-(1,2-cyclohexanediylethylene)bis(3-nitrosalicylideneiminato), are reported. The enantiomer contains two crystallographically independent dysprosium(iii) ions, each chelated by two enantiopure 3-NO2salcy(2-) ligands forming a [DyN4O4] core. Detailed magnetic studies on compound reveal a field-induced dual magnetic relaxation behavior, originating from single ion anisotropy and intermolecular interactions, respectively.

11.
Dalton Trans ; 44(9): 4271-9, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-25633162

RESUMEN

Three new chain compounds in which the Mn2(salen)2 dimers are bridged by O-P-O units are reported, namely, [Mn2(salen)2(C6H9PO3H)](ClO4) (1), [Mn2(salen)2(C6H5PO3H)](ClO4) (2) and [Mn2(salen)2(C6H5PHO2)](ClO4) (3). The phosphonate or phosphinate ligands adopt a syn-anti bidentate bridging mode in 1, while a syn-syn bidentate bridging mode in 2 and 3, thus leading to a difference in the Mn-O···O-Mn torsion angle over the O-P-O bridge. Compound 1 shows a paramagnetic behavior with dominant antiferromagnetic interactions. In compounds 2 and 3, the antiferromagnetic interactions through the O-P-O bridges are considerably stronger than those in 1. They display coexistence of single chain magnet (SCM) behaviour with a spin canted structure and metamagnetism at low temperature. The results demonstrate that the magnetic dynamics of the O-P-O bridged Mn2(salen)2 chains may be modulated by selecting suitable phosphonate or phosphinate ligands.

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