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1.
Ann Anat ; 227: 151431, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31634560

RESUMO

Histological analysis is a fundamental and principal method used in biological research and even for disease diagnosis. The result shows the status of cells and tissues in organs and enables us to infer the condition of the whole body. The tissue staining method known as hematoxylin and eosin staining (HE) is one of the most general methods of investigating the status of cells and tissues. Hematoxylin stains the nucleus violet and eosin stains cytosol pink. HE staining shows the unique morphologies of tissues and cells. However, after being stained with HE, tissues are very difficult to use in another histological analysis because hematoxylin is hard to remove from the sections due to its stain stability. Therefore, serial sections of the tissue are used to obtain more information through another staining, including immunohistochemistry. The adjacent tissue section is not the same as the HE-stained section, however, so the results from the adjacent sections can cause confusion or ambiguity. The present study showed that our decolorization solution can decolor the hematoxylin or iron hematoxylin stain from stained structures, including the nucleus, and the decolored section could be stained again in another staining, including immunohistochemistry. This decolorization method is very valuable, in that it can determine the accurate distribution of substances and features in cells and tissues, and thus it can improve the robustness of the resulting data.


Assuntos
Corantes/metabolismo , Corantes Fluorescentes/metabolismo , Animais , Compostos Azo/metabolismo , Ácidos Carboxílicos/química , Quelantes/química , Amarelo de Eosina-(YS)/metabolismo , Hematoxilina/metabolismo , Imuno-Histoquímica , Verde de Metila/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Microscopia de Fluorescência , Ácidos Fosfóricos/química , Nitrato de Prata/metabolismo , Trometamina/química
2.
Analyst ; 144(24): 7468-7477, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31710318

RESUMO

This study deals with the nonaqueous capillary electrophoretic enantioseparation of twenty-two amino alcohol drugs with a maltobionic acid (MA)-based ionic liquid (tetramethylammonium maltobionic acid, TMA-MA) as the novel chiral selector. In consideration of the poor solubility of MA in organic solvents, we managed to transform MA into ionic liquids (ILs) for the first time. Interestingly, this chiral selector exhibited powerful enantioselectivity towards the model analytes in company with boric acid. Systematical experiments were carried out to investigate the influence of concentration of TMA-MA, boric acid and tris (hydroxymethyl) aminomethane (Tris) as well as applied voltage on the enantioseparation. A great majority of enantiomers (except labetalol) were baseline separated under the optimized conditions and the effect of the molecular structure of amino alcohol drugs on the chiral separation was discussed. In addition, electrophoretic experiments, nuclear magnetic resonance (NMR), mass spectrometry (MS) and molecular modeling with the Gaussian program were employed to demonstrate the mechanism of chiral recognition. Based on the formation of an ionic liquid-boric acid-analyte complex, hydrogen binding was mainly responsible for enantioseparation.


Assuntos
Amino Álcoois/isolamento & purificação , Dissacarídeos/química , Líquidos Iônicos/química , Compostos de Amônio Quaternário/química , Amino Álcoois/química , Ácidos Bóricos/química , Dissacarídeos/síntese química , Eletroforese Capilar/métodos , Ligação de Hidrogênio , Líquidos Iônicos/síntese química , Modelos Moleculares , Compostos de Amônio Quaternário/síntese química , Estereoisomerismo , Trometamina/química
3.
Org Biomol Chem ; 17(24): 5908-5912, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31145403

RESUMO

We describe the biocompatible conjugation of the Tris base to 2-formyl and 2-acetylphenylboronic acid (abbreviated as 2-FPBA and 2-APBA respectively), which have emerged as a versatile chemotype for fast biocompatible conjugation reactions. Tris base was found to react with 2-FPBA/APBA to give oxazolidinoboronate (OzB) complexes, analogous to the thiazolidinoboronate (TzB) and imidazolidinoboronate (IzB) complex formation that we recently reported. The Tris conjugations proceed well in complex biological media, and in contrast to the TzB/IzB complexes, the Tris conjugates exhibit superior kinetic stability (dissociation over days) as well as chemical stability against oxidation. We demonstrate the utility of such conjugation chemistries via a small molecule-induced peptide cyclization in blood serum.


Assuntos
Materiais Biocompatíveis/química , Ácidos Borônicos/síntese química , Trometamina/química , Ácidos Borônicos/química , Cinética , Estrutura Molecular
4.
Andrologia ; 51(8): e13322, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31134645

RESUMO

The aim of the present study was to determine the protective effects of pomegranate juice in tris-based extender on semen parameters, computer-assisted sperm analysis (CASA) motion characteristics and field fertility of post-thawed Nili Ravi buffalo (Bubalus bubalis) bull spermatozoa. Two consecutive ejaculates/collection from each of the five adult Nili Ravi buffalo bulls were collected with artificial vagina at 42°C for a period of 7 weeks, diluted in extender containing different concentrations of pomegranate juice (0.0%, 2.5%, 5%, 7.5% and 10%). Diluted samples were packed and frozen in 0.54 ml French straws. The addition of 10% pomegranate juice in extender significantly improved post-thaw sperm morphology (%), motilities (CASA total motility, progressive motility (%) as well as VAP, VSL, VCL, STR, DAP, DSL) compared to the control group (p < 0.05). Plasma membrane, acrosome membrane and DNA integrity were significantly higher in extender with 10% pomegranate juice than the control group (p < 0.05). Field fertility rate (60.39% vs. 46.53%) was higher (p < 0.05) in extender with 10% pomegranate juice as compared to the control. It is therefore concluded that the addition of 10% pomegranate juice in tris-based extender improves post-thaw semen parameters, CASA motion dynamics and field fertility in Nili Ravi buffaloes.


Assuntos
Sucos de Frutas e Vegetais , Inseminação Artificial/métodos , Soluções para Preservação de Órgãos/farmacologia , Romã (Fruta)/química , Preservação do Sêmen/métodos , Criação de Animais Domésticos , Animais , Búfalos , Ácido Cítrico/química , Ácido Cítrico/farmacologia , Masculino , Soluções para Preservação de Órgãos/química , Paquistão , Preservação do Sêmen/veterinária , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Trometamina/química , Trometamina/farmacologia
5.
J Pharm Biomed Anal ; 171: 1-7, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30953797

RESUMO

Secreted recombinant activated clotting factor VII activated (rFVIIa) in cell culture media missing gamma-carboxyglutamic acid (Gla) domain as a result of failure in gamma-carboxylation or cell lysis is called Gla-domainless impurity which has less negative charge compared to native rFVIIa. Based on risk assessment, this type of impurity is considered as critical drug product quality attribute of rFVIIa and its quantitative analysis in product batches is a critical issue in quality control laboratories. Analysis of Gla-domainless impurity is accomplished by Strong Anion Exchange Chromatography (SAX) in recombinant factor VIIa using Tris and Bis-Tris propane salt buffers as equilibrating buffers and high concentration ammonium acetate as an eluent. Appearance of ghost peaks with notable intensity during elution time of Gla-domainless impurity caused distortion of the related peak and interference with robust and accurate quantification of this impurity. Subsequently, the ghost peak was analyzed by LC-ESI-MS to determine the structure which showed the m/z values at 905.27, 623.53 and 341.60 and 563.73. To find the source of these ghost peaks, quality of water, buffer salts and Chelex-100 together with ionic strength of mobile phase A (addition of 25 mM NaCl) were considered as affecting parameters and several experiments designed with DOE software to optimize the best condition of highest quality the method with lowest signal of ghost peak noises. By interpretation of DOE result, it is concluded that high grade water and buffer salt along with high quality Chelex-100 resins are important factors to achieve a method with lowest ghost peaks. However, addition of 25 mM NaCl to mobile phase A with either lower quality buffer salts or lower water grade yields high quality chromatogram peak with acceptable ghost peaks. LC/MS analysis indicates that macrostructures of Bis-Tris propane made up as a result of hydrogen bonds with each other or Tris molecules can be the source of ghost peaks.


Assuntos
Ácido 1-Carboxiglutâmico/análise , Cromatografia por Troca Iônica/normas , Contaminação de Medicamentos , Fator VIIa/normas , Espectrometria de Massas por Ionização por Electrospray/normas , Trometamina/análogos & derivados , Tampões (Química) , Química Farmacêutica , Proteínas Recombinantes/normas , Trometamina/química
6.
Analyst ; 144(8): 2565-2573, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30882808

RESUMO

Native mass spectrometry is widely used to probe the structures, stabilities, and stoichiometries of proteins and biomolecular complexes in aqueous solutions, typically containing volatile ammonium acetate or ammonium bicarbonate buffer. In this study, nanoelectrospray emitters with submicron tips are used to produce significantly desalted ions of RNase A and a reduced, alkylated form of this protein, RA-RNase A, from solutions containing 175 mM ammonium acetate, as well as sodium chloride and Tris containing solutions with the same nominal ionic strength and pH. The charge-state distributions formed by nanoelectrospray ionization and tyrosine fluorescence emission data as a function of temperature from these solutions indicate that the folded form of RA-RNase A in solution is stabilized when ammonium acetate is replaced by increasing quantities of NaCl and Tris. Ion mobility data for the 7+ charge state of RA-RNase A indicates that the protein conformation in ammonium acetate changes with increasing concentration of NaCl which stablizes more compact structures. These results are consistent with observations reported 130 years ago by Hofmeister who found that ion identity can affect the stabilities and the structures of proteins in solution. This study indicates the importance of buffer choice when interpreting native mass spectrometry data.


Assuntos
Acetatos/química , Ribonuclease Pancreático/química , Cloreto de Sódio/química , Trometamina/química , Alquilação , Animais , Tampões (Química) , Bovinos , Oxirredução , Conformação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Espectrometria de Massas por Ionização por Electrospray/métodos , Temperatura
7.
Methods Mol Biol ; 1952: 91-102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30825168

RESUMO

The average molecular mass of hyaluronan (HA) in most healthy biological fluids and tissues is usually about 6000-8000 kDa, but the biosynthetic mechanism results in a polydisperse mixture of sizes. Subsequent enzymatic degradation, or the action of reactive oxygen and nitrogen species, can further increase polydispersity and decrease the average size. Fragmented HA can be a biomarker of inflammation. In addition, reductions in HA size are associated with tissue remodeling and repair processes. Some cell-surface receptor proteins have been reported to have HA-binding affinities that are size specific, and participate in activation of signaling cascades controlling multiple aspects of cell behavior. Here we describe simple agarose gel electrophoresis protocols for the determination of the molecular mass distribution of HA isolated from tissues and fluids.


Assuntos
Eletroforese em Gel de Ágar/métodos , Ácido Hialurônico/química , Acetatos/química , Ácidos Bóricos/química , Densitometria/métodos , Ácido Edético/química , Etilenodiaminas/química , Humanos , Ácido Hialurônico/isolamento & purificação , Peso Molecular , Coloração e Rotulagem/métodos , Trometamina/química
8.
Methods Mol Biol ; 1922: 239-250, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838582

RESUMO

The organic material in developing dentin is 90% type I collagen and 10% non-collagenous proteins. The key to understanding dentin biomineralization is to study how these proteins collectively precipitate and organize hydroxyapatite crystals. The first step in characterizing the proteins within a mineralizing matrix is to efficiently extract and isolate the essential molecular participants and elucidate their structural and biochemical properties. In this study, we expanded previous approaches to develop an improved strategy for the extraction of extracellular matrix proteins from the dentin of developing teeth. Proteins in dentin powder were sequentially extracted in the order Tris-guanidine buffer, HCl-formic acid solution, acetic acid-NaCl solution, Tris-NaCl buffer, and a second Tris-guanidine buffer. Individual fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), by gelatin or casein zymography, and by Western blot analysis using dentin sialoprotein (DSP)- or dentin glycoprotein (DGP)-specific antibodies. This approach was used to purify assorted porcine dentin non-collagenous proteins.


Assuntos
Western Blotting/métodos , Dentina/química , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas da Matriz Extracelular/isolamento & purificação , Glicoproteínas/isolamento & purificação , Fosfoproteínas/isolamento & purificação , Sialoglicoproteínas/isolamento & purificação , Dente/química , Ácido Acético/química , Animais , Dentina/crescimento & desenvolvimento , Formiatos/química , Guanidina/química , Suínos , Dente/crescimento & desenvolvimento , Trometamina/química
9.
Anal Sci ; 35(4): 455-460, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30643097

RESUMO

A novel ex vivo method to simultaneously evaluate hepatic glucose utilization, uptake, and production was developed in rats. The right lateral lobe of the liver was perfused with Krebs-Henseleit bicarbonate buffer containing 5 mmol/L uniformly labeled 13C-glucose ([U-13C]-glucose). The whole glucose concentration in the perfusate was measured by colorimetric assay, and the concentrations of [U-12C]-glucose (natural isotope) or [U-13C]-glucose were estimated on the basis of the abundance ratio of [U-12C]-glucose or [U-13C]-glucose, which were measured by GC-MS. The difference in whole glucose and [U-13C]-glucose concentrations between the baseline and effluent perfusate represents hepatic glucose utilization and glucose uptake, respectively. The [U-12C]-glucose concentration in the effluent perfusate corresponds to hepatic glucose production. With this method, we clarified the precise mechanism that underlies the hepatic impairment of diabetic animals and pharmacological effects of anti-diabetic agents. Thus, this method is useful for the pathophysiological and pharmacological research of type 2 diabetes.


Assuntos
Glucose/metabolismo , Fígado/metabolismo , Animais , Isótopos de Carbono , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Glucose/antagonistas & inibidores , Glucose/química , Hipoglicemiantes/farmacologia , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Trometamina/química , Trometamina/metabolismo
10.
Biochim Biophys Acta Proteins Proteom ; 1867(4): 359-366, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30639425

RESUMO

BACKGROUND: Characterizing the thermodynamic parameters behind metal-biomolecule interactions is fundamental to understanding the roles metal ions play in biology. Isothermal Titration Calorimetry (ITC) is a "gold-standard" for obtaining these data. However, in addition to metal-protein binding, additional equilibria such as metal-buffer interactions must be taken into consideration prior to making meaningful comparisons between metal-binding systems. METHODS: In this study, the thermodynamics of Ca2+ binding to three buffers (Bis-Tris, MES, and MOPS) were obtained from Ca2+-EDTA titrations using ITC. These data were used to extract buffer-independent parameters for Ca2+ binding to human cardiac troponin C (hcTnC), an EF-hand containing protein required for heart muscle contraction. RESULTS: The number of protons released upon Ca2+ binding to the C- and N-domain of hcTnC were found to be 1.1 and 1.2, respectively. These values permitted determination of buffer-independent thermodynamic parameters of Ca2+-hcTnC binding, and the extracted data agreed well among the buffers tested. Both buffer and pH-adjusted parameters were determined for Ca2+ binding to the N-domain of hcTnC and revealed that Ca2+ binding under aqueous conditions and physiological ionic strength is both thermodynamically favorable and driven by entropy. CONCLUSIONS: Taken together, the consistency of these data between buffer systems and the similarity between theoretical and experimental proton release is indicative of the reliability of the method used and the importance of extracting metal-buffer interactions in these studies. GENERAL SIGNIFICANCE: The experimental approach described herein is clearly applicable to other metal ions and other EF-hand protein systems.


Assuntos
Cálcio/química , Troponina C/química , Ácidos Alcanossulfônicos/química , Tampões (Química) , Ácido Edético/química , Coração , Humanos , Concentração de Íons de Hidrogênio , Morfolinas/química , Termodinâmica , Trometamina/análogos & derivados , Trometamina/química
11.
Chembiochem ; 20(1): 96-102, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30252998

RESUMO

Biocatalytic production of lactones, and in particular ϵ-caprolactone (CL), have gained increasing interest as a greener route to polymer building blocks, especially through the use of Baeyer-Villiger monooxygenases (BVMOs). Despite several advances in the field, BVMOs, however, still suffer several practical limitations. Alcohol dehydrogenase (ADH)-mediated lactonization of diols in turn has received far less attention and very few enzymes have been identified for the conversion of diols to lactones, with horse-liver ADH (HLADH) remaining the catalyst of choice. Screening of a diverse panel of ADHs, AaSDR-1, a member of the short-chain dehydrogenase/reductase family, was found to produce ϵ-caprolactone from hexane-1,6-diol. Moreover, cofactor regeneration by an NADH oxidase eliminated the requirement of co-substrates, yielding water as the sole by-product. Despite lower turnover frequencies as compared to HLADH, higher selectivity was found for the production of CL, with HLADH forming significant amounts of 6-hydroxyhexanoic acid and adipic acid through aldehyde dehydrogenation/oxidation of the gem-diol intermediates. Also, CL yield were shown to be dependent on buffer choice, as structural elucidation of a Tris adduct confirmed the buffer amine to react with aliphatic aldehydes forming a Schiff-base intermediate which through further ADH oxidation, forms a tricyclic acetal product.


Assuntos
Glicóis/química , Redutases-Desidrogenases de Cadeia Curta/química , Animais , Bactérias/enzimologia , Biocatálise , Caproatos/metabolismo , Ciclização , Fungos/enzimologia , Lactonas/metabolismo , Modelos Químicos , Oxirredução , Plantas/enzimologia , Especificidade por Substrato , Trometamina/química
12.
Methods Mol Biol ; 1855: 269-277, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30426423

RESUMO

Polyacrylamide gel electrophoresis (PAGE) is one of the most powerful tools used for protein analysis. We describe the use of Tris-acetate buffer and 3-15% polyacrylamide gradient gels to simultaneously separate proteins in the mass range of 10-500 kDa. We show that this system is highly sensitive, it has good resolution and high reproducibility, and it can be used for general applications of PAGE such as Coomassie Brilliant Blue staining and immunoblotting. Moreover, we describe how to generate mini Tris-acetate polyacrylamide gels to use them in miniprotein electrophoresis systems. These economical gels are easy to generate and to manipulate and allow a rapid analysis of proteins. All these features make the Tris-acetate-PAGE system a very helpful tool for protein analysis.


Assuntos
Acetatos/química , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas/análise , Trometamina/química , Resinas Acrílicas/química , Animais , Eletroforese em Gel de Poliacrilamida/instrumentação , Desenho de Equipamento , Géis/química , Humanos , Peso Molecular , Proteínas/isolamento & purificação
13.
Methods Mol Biol ; 1855: 491-494, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30426443

RESUMO

We describe here an ultrafast method for electrophoresing proteins on SDS-PAGE. Previously we reported a method to complete SDS-PAGE and immunoblotting in an hour, including electrophoresing proteins at 70°C in 10 min. Here we show that we can electrophorese molecular weight standards and bovine serum albumin on a 4-20% gradient gel in well under 10 min using heated (44 °C) Laemmli running buffer and high voltage.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Proteínas/análise , Animais , Bovinos , Eletroforese em Gel de Poliacrilamida/economia , Eletroforese em Gel de Poliacrilamida/instrumentação , Calefação , Peso Molecular , Proteínas/isolamento & purificação , Soroalbumina Bovina/análise , Soroalbumina Bovina/isolamento & purificação , Dodecilsulfato de Sódio/química , Fatores de Tempo , Trometamina/química
14.
Colloids Surf B Biointerfaces ; 173: 233-241, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30300829

RESUMO

In this work, we aimed at improved viability and growth of the microalga Chlamydomonas reinhardtii in transparent silica hydrogels based on low-ethanol, low-sodium and low-propylamine synthesis. Investigation into replacement of conventional base KOH by buffers dipotassium phosphate and tris(hydroxymethyl)aminomethane along with increased precursor concentrations yielded an aqueous synthesis route which provided a gelation within 10 min, absorptions below 0.1 and elastic moduli of 0.04-4.23 kPa. The abrasion resistance enhanced by 41% compared to calcium alginate hydrogels and increased to 70-85% residual material on addition of chitosan. Entrapment of microalgae in low-sodium and low-propylamine silica hydrogels maintained the PSII quantum yield above 0.3 and growth rates of 0.23 ± 0.01 d-1, similarly to cells entrapped in calcium alginate. These promising results pave the way for the entrapment of sensitive, photosynthetically active and growing cells for in robust biotechnological applications.


Assuntos
Materiais Biocompatíveis/química , Células Imobilizadas/efeitos dos fármacos , Chlamydomonas reinhardtii/efeitos dos fármacos , Hidrogéis/química , Fotossíntese/efeitos dos fármacos , Alginatos/química , Materiais Biocompatíveis/farmacologia , Tampões (Química) , Células Imobilizadas/citologia , Quitosana/química , Chlamydomonas reinhardtii/citologia , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Módulo de Elasticidade , Hidrogéis/farmacologia , Fosfatos/química , Compostos de Potássio/química , Dióxido de Silício/química , Trometamina/química
15.
Colloids Surf B Biointerfaces ; 175: 606-613, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30580151

RESUMO

Plasmid DNA in aerated aqueous solution is used as a probe to determine whose of the reactive oxygen species (ROS) generated after absorption of ultra-soft X-rays (USX) take part in biomolecule damage in the presence and in absence of Gold Nano-Particles (GNP) and specific scavengers. Citrate-coated GNPs with core sizes of 6, 10 and 25 nm are synthetized and characterized, especially in terms of plasmon band shift, ζ-potential and hydrodynamic radii (respectively 9, 21 and 30 nm). We confirm the radiosensitizing effect of GNP and show that the SSB number per plasmid increases when, for a same mass of gold element, the core size of the gold nanoparticles decreases. Hydroxyl radicals (OH) are scavenged using the positively-charged 2-amino-2-hydroxymethyl-1,3-propanediol (TRIS) and the neutral dimethyl sulfoxide (DMSO) molecules. Due to both negatively-charged environments of DNA and GNP, at identical scavenging capacity, TRIS is more effective at quenching OH than DMSO. The strong radiosensitizing effect of hydroxyl radicals is confirmed. Methanoate anions are then used to transform OH into hydrogen peroxide; the latter being known to be non-aggressive regarding DNA in the absence of easily oxidable metallic ions (Fenton reactions). Surprisingly, in the presence of GNP, high DNA damage yields are observed even though hydrogen peroxide might not be hold as responsible. Conversely, the radiosensitizing effect of GNP is not observed anymore when H2O2 is scavenged using pyruvate ions. We demonstrate that hydrogen peroxide constitutes quite unexpectedly a hidden stock of OH which are activated at the surface of the GNP by decomposition of H2O2 molecules.


Assuntos
Quebras de DNA de Cadeia Simples/efeitos da radiação , Depuradores de Radicais Livres/química , Peróxido de Hidrogênio/química , Nanopartículas Metálicas/efeitos da radiação , Plasmídeos/efeitos da radiação , Radiossensibilizantes/química , Ácido Cítrico/química , Dimetil Sulfóxido/química , Formiatos/química , Ouro/química , Radical Hidroxila/química , Nanopartículas Metálicas/química , Tamanho da Partícula , Plasmídeos/química , Ácido Pirúvico/química , Soluções , Trometamina/química , Raios X
16.
Anim Reprod Sci ; 198: 145-153, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30301622

RESUMO

One reason for reduced longevity of chilled dog semen is oxidative stress. The antioxidant glutathione (GSH) improves viability of frozen-thawed dog sperm, but its effect on chilled dog semen has not been investigated. An experiment consisting of two parts was performed: Sperm rich fractions, SRF, were split, diluted with a Tris-egg yolk (TEY) extender containing 0, 5 or 10 mM GSH and stored at 4 °C for 10 days (Part 1; n = 19) or 4 days (Part 2; n = 11), respectively. For Part 1 of the study, percentage (%) of motile, viable, morphologically abnormal spermatozoa and % acrosomal deviations were assessed on days 0, 1, 2, 4 and 10 after dilution. For % sperm motility, samples from all three aliquots of each SRF (0/5/10 mM GSH) were pipetted simultaneously and analysed in a randomised order (time point of analysis, TPA). In Part 2 of the study, motility analysis was performed during 4 days storage and samples were analysed immediately after pipetting (part 2). Most investigated parameters were affected by storage time. For motility variables, there was an effect of GSH identified for circular, CM (ANOVA, Part 1: P = 0.05, Part 2: P < 0.0001) and local motility, LM (ANOVA, Part 2: P = 0.004). Furthermore, there was a trend for an interaction between time and sperm treatment for CM (Part 2: P = 0.077). In conclusion, in the present study there was not an overall positive effect of GSH addition (5/10 mM) on sperm motility in chilled dog semen samples that were characterised to be of good quality during 4- and 10-days of storage.


Assuntos
Crioprotetores/farmacologia , Cães , Gema de Ovo , Glutationa/farmacologia , Refrigeração/métodos , Trometamina/farmacologia , Animais , Gema de Ovo/química , Gema de Ovo/fisiologia , Masculino , Refrigeração/veterinária , Sêmen/citologia , Sêmen/efeitos dos fármacos , Análise do Sêmen , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade Espermática/efeitos dos fármacos , Trometamina/química
17.
Int J Nanomedicine ; 13: 5433-5447, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30271139

RESUMO

Background: Due to the increasing number of patients with bone defects, bone nonunion and osteo-myelitis, tumor and congenital diseases, bone repair has become an urgent problem to be solved. Methods: In this study, the 3D-printed scaffolds of ternary composites containing mesoporous bioglass fibers of magnesium calcium silicate (mMCS), gliadin (GA) and polycaprolactone (PCL) were fabricated using a 3D Bioprinter. Results: The compressive strength and in vitro degradability of the mMCS/GA/PCL composites (MGPC) scaffolds were improved with the increase of mMCS content. In addition, the attachment and proliferation of MC3T3-E1 cells on the scaffolds were significantly promoted with the increase of mMCS content. Moreover, the cells with normal phenotype attached and spread well on the scaffolds surfaces, indicating good cytocompatibility. The scaffolds were implanted into the femur defects of rabbits, and the results demonstrated that the scaffold containing mMCS stimulated new bone formation and ingrowth into the scaffolds through scaffolds degradation in vivo. Moreover, the expression of type I collagen into scaffolds was enhanced with the increase of mMCS content. Conclusion: The 3D-printed MGPC scaffold with controllable architecture, good biocompatibility, high compressive strength, proper degradability and excellent in vivo osteogenesis has great potential for bone regeneration.


Assuntos
Desenvolvimento Ósseo , Osso e Ossos/fisiologia , Cerâmica/química , Força Compressiva , Gliadina/química , Poliésteres/química , Impressão Tridimensional , Tecidos Suporte/química , Animais , Materiais Biocompatíveis , Regeneração Óssea , Compostos de Cálcio/química , Adesão Celular , Linhagem Celular , Proliferação de Células , Colágeno Tipo I/metabolismo , Feminino , Fêmur/patologia , Humanos , Silicatos de Magnésio/química , Camundongos , Osteoblastos/citologia , Osteoblastos/ultraestrutura , Osteogênese/fisiologia , Porosidade , Coelhos , Silicatos/química , Soluções , Trometamina/química
18.
Eur J Pharm Biopharm ; 131: 109-119, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30086393

RESUMO

Although salt formation is the most ubiquitous and effective method of increasing the solubility and dissolution rates of acidic and basic drugs, it consumes large quantities of organic solvents and is a batch process. Herein, we show that the dissolution rate of indomethacin (a poorly water-soluble drug) can be increased by using hot melt extrusion of a 1:1 (mol/mol) indomethacin:tromethamine mixture to form a highly crystalline salt, the physicochemical properties of which are investigated in detail. Specifically, pH-solubility studies demonstrated that this salt exhibited a maximal solubility of 19.34 mg/mL (>1000 times that of pure indomethacin) at pH 8.19. A solvent evaporation technique was also used for salt formation. Spectroscopic analyses (infrared, nuclear magnetic resonance) of both; demonstrated, in situ salt formation with proton transfer. Powder X-ray diffraction and differential scanning calorimetry confirmed the crystalline nature of salts formed by both methods. Even though a number of amorphous salts of acidic drugs have been reported, the formation of a crystalline salt of an acidic drug by hot melt extrusion is completely unprecedented, which makes this study an important benchmark for the pharmaceutical production industry.


Assuntos
Anti-Inflamatórios não Esteroides/química , Indometacina/química , Trometamina/química , Química Farmacêutica , Cristalização , Composição de Medicamentos , Excipientes , Temperatura Alta , Concentração de Íons de Hidrogênio , Solubilidade , Solventes
19.
Int J Toxicol ; 37(1_suppl): 5S-18S, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29761730

RESUMO

The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) reviewed the safety of tromethamine, aminomethyl propanediol, and aminoethyl propanediolas used in cosmetics. All 3 ingredients are reported to function in cosmetics as pH adjusters, and tromethamine and aminomethyl propanediol are also reported to function as fragrance ingredients. The Panel reviewed relevant animal and human data related to these ingredients, along with a previous safety assessment of aminomethyl propanediol. The Panel concluded that tromethamine, aminomethyl propanediol, and aminoethyl propanediol are safe in cosmetics in the practices of use and concentration as given in this safety assessment.


Assuntos
Cosméticos/efeitos adversos , Cosméticos/química , Propilenoglicóis/efeitos adversos , Trometamina/efeitos adversos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Qualidade de Produtos para o Consumidor , Humanos , Estrutura Molecular , Propilenoglicóis/administração & dosagem , Propilenoglicóis/química , Propilenoglicóis/farmacocinética , Ratos , Trometamina/administração & dosagem , Trometamina/química , Trometamina/farmacocinética
20.
J Microbiol Biotechnol ; 28(4): 613-621, 2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29618181

RESUMO

In this study, interface-assembled carbonyl reductase (IACR) was prepared and used in the synthesis of S-licarbazepine in a toluene/Tris-HCl biphasic system. The carbonyl reductase (CR) was conjugated with polystyrene to form a surfactant-like structure at the interface of the toluene/Tris-HCl biphasic system. The interface-assembled efficiency of IACR reached 83% when the CR (180 U/mg) and polystyrene concentration were 8 × 10² g/ml and 3.75 × 10³ g/ml, respectively. The conversion reached 95.6% and the enantiometric excess of S-licarbazepine was 98.6% when 3.97 × 106 nmol/l oxcarbazepine was converted by IACR using 6% ethanol as a co-substrate in toluene/Tris-HCl (12.5:10) at 30°C and 43 ×g for 6 h. IACR could be reused efficiently five times.


Assuntos
Oxirredutases do Álcool/metabolismo , Dibenzazepinas/metabolismo , Tolueno/química , Trometamina/química , Oxirredutases do Álcool/química , Carbamazepina/análogos & derivados , Carbamazepina/metabolismo , Dibenzazepinas/química , Etanol , Concentração de Íons de Hidrogênio , Hidroxiapatitas , NAD/química , Oxcarbazepina , Poliestirenos/metabolismo , Especificidade por Substrato , Temperatura
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