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1.
Mikrochim Acta ; 189(5): 206, 2022 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-35501613

RESUMO

Concerns for agri-food safety and environmental management require development of simple to use and cost- and time-effective multiplex sensors for point-of-need (PON) chemical analytics by public end-user. Simultaneous detection of nitrates, phosphates, and pH is of importance in soil and water analysis, agriculture, and food quality assessment. This article demonstrates a suite of stainless steel microneedle electrochemical sensors for multiplexed measurement of pH, nitrate, and phosphate using faradaic capacitance derived from cyclic voltammetry as the mode of detection. The multi-target microneedle sensors were fabricated by layer-by-layer (LbL) assembly in a stainless steel hypodermic microneedle substrate. For nitrate sensing, the stainless steel was coated with carbon nanotube/cellulose nanocrystal (CNT)/CNC) decorated with silver nanoparticles (Ag). For pH measurement, the polyaniline (pANI) was coated onto the CNT/CNC@Ag film, while for phosphate detection, the CNT/CNC/Ag @pANI microneedle was further decorated with ammonium molybdenum tetrahydrate (AMT). The microelectrode platforms were characterized by FTIR, Raman, and microscopic techniques. The nitrate- and phosphate-based microneedle electrochemical sensors had excellent selectivity and sensitivity, with a determined limit of detection (LOD) of 0.008 mM and 0.007 mM, respectively. The pH microneedle sensor was responsive to pH in the linear range of 3-10. The three microneedle sensors yielded repeatable results, with a precision ranging from 4.0 to 7.5% RSD over the concentration ranges tested. The inexpensive (~ 1 $ CAD) microneedle sensors were successfully verified for use in quantification of nitrate, pH, and phosphate in brewed black coffee as a real sample. As such, the microneedle sensors are economical devices and show great promise as robust platforms for PON precision chemical analytics.


Assuntos
Nanopartículas Metálicas , Nitratos , Celulose , Técnicas Eletroquímicas/métodos , Concentração de Íons de Hidrogênio , Fosfatos , Prata/química , Aço Inoxidável
2.
J Avian Med Surg ; 36(1): 28-38, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35526162

RESUMO

The objective of this study was to construct a calibration phantom for bone mineral density (BMD) measurements adapted to avian anatomy by quantitative computed tomography. The determination of BMD is important to assess avian osteoporosis in poultry at production facilities and to study biological features in association with flight patterns in birds. Quantitative computed tomography measured in Hounsfield units is a well-established technique for BMD measurements. Translation of Hounsfield units into the International System of Units (mg/cm3) requires the use of a calibration phantom. Although calibration phantoms for routine use in humans are commercially available, phantoms suited to avian anatomy are not. A liquid dipotassium hydrogen phosphate calibration standard was constructed out of commercially available materials, easily allowing for variations in size, bone diameter, and adaptation to avian skeletal anatomy. Periodically, quantitative computed tomography scans were performed to monitor constant correlation to the calibration standard over 3 months and to monitor for the potential influence of gas bubbling and water evaporation in the rods on BMD measurements. Finally, the calibration phantom was tested for BMD measurements with carcasses from 2 bird species, including 3 peregrine falcons (Falco peregrinus; 2 juvenile males, 1 adult female with inactive reproductive status) and 4 Eurasian kestrels (Falco tinnunculus; 1 juvenile and 2 adult males, 1 adult female with inactive reproductive status). Results demonstrated stability of the calibration phantom without the need to refill or replace rods, plus a stable correlation line (R 2 = .99) over the 3-month evaluation period. It was possible to place the phantom directly on the bird carcasses, close to the measured bones, to improve BMD analysis. As evaluated, the phantom appeared to be adaptive to avian skeletal anatomy. Moreover, it was possible to build the phantom within 24 hours from commercially available materials.


Assuntos
Densidade Óssea , Tomografia Computadorizada por Raios X , Animais , Aves , Cadáver , Feminino , Masculino , Imagens de Fantasmas , Fosfatos , Compostos de Potássio , Tomografia Computadorizada por Raios X/veterinária
3.
Sci Rep ; 12(1): 7358, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513558

RESUMO

Plasma approaches metastability with respect to its calcium and phosphate content, with only minor perturbations in ionic activity needed to sustain crystal growth once nucleated. Physiologically, calcium and phosphate are intermittently absorbed from the diet each day, yet plasma concentrations of these ions deviate minimally post-prandially. This implies the existence of a blood-borne mineral buffer system to sequester calcium phosphates and minimise the risk of deposition in the soft tissues. Calciprotein particles (CPP), endogenous mineral-protein colloids containing the plasma protein fetuin-A, may fulfill this function but definitive evidence linking dietary mineral loading with their formation is lacking. Here we demonstrate that CPP are formed as a normal physiological response to feeding in healthy adults and that this occurs despite minimal change in conventional serum mineral markers. Further, in individuals with Chronic Kidney Disease (CKD), in whom mineral handling is impaired, we show that both fasting and post-prandial levels of CPP precursors are markedly augmented and strongly inversely correlated with kidney function. This study highlights the important, but often neglected, contribution of colloidal biochemistry to mineral homeostasis and provides novel insight into the dysregulation of mineral metabolism in CKD.


Assuntos
Fosfatos , Insuficiência Renal Crônica , Adulto , Biomarcadores , Cálcio , Cálcio na Dieta , Feminino , Humanos , Rim/metabolismo , Cinética , Masculino , Minerais/metabolismo
4.
Artigo em Alemão | MEDLINE | ID: mdl-35523164

RESUMO

OBJECTIVES: This study was aimed to assess the distribution and frequency of uroliths in cats as well as to evaluate gender-, age-, and breed-specific differences. MATERIAL AND METHODS: 3629 uroliths from cats in Germany were analyzed by infrared-spectroscopy during the period 2016-2020. The majority (3300) of the uroliths originated from purebred cats of 22 breeds. RESULTS: Uroliths were prevalent in the order of male neutered (45.3 %), female spayed (35.3 %), male intact (7.4 %), and female intact cats (6.3 %). Median age of the cats with uroliths was 7 years, although it varied slightly depending on types of the urolith. The most frequent uroliths were calcium oxalate (59.5 %), followed by struvite (33.7 %), ammonium urate (2 %), calcium phosphate (1.7 %), cystine (0.7 %) and xanthine (0.4 %). Males (59.4 %) and females (59.2 %) showed nearly identical prevalence of calcium oxalates, whereas it significantly diverged in castrated (60.2 %) versus intact animals (54.4 %; p = 0.01). With regard to struvites, male cats (32.6 %) were less prone than females (35.4 %; p = 0.08) while intact cats (38.2 %) significantly outnumbered the castrated cohorts (33.1 %; p = 0.02). The prevalence for calcium oxalate uroliths increased by 6.6 % during the study period, contrasting a decrease of 5.5 % for struvites. Some breeds (> 10 individuals) showed significantly higher propensities than others for urolith formation. Calcium oxalates were significantly more frequent in British shorthair cats (85.2 %), Ragdoll (75 %), Scottish fold (74.1 %) and Persians (72.4 %). Struvites were prevailing in Norwegian forest cats (48.5 %), British longhair (41.7 %), European shorthair (41.7 %) and Siberian forest cats (36.8 %). Siamese cats had the significantly highest percentage of cystine uroliths (16 %). CONCLUSIONS AND CLINICAL RELEVANCE: The occurrence of urine calculi in cats from Germany was found to be most frequent for calcium oxalate and struvite types. We also found breed-, age-, gender- specific differences in addition to variations depending on the neutering status of the animals.


Assuntos
Doenças do Gato , Cálculos Urinários , Fatores Etários , Animais , Cálcio , Oxalato de Cálcio/química , Doenças do Gato/epidemiologia , Gatos , Cistina , Feminino , Alemanha/epidemiologia , Compostos de Magnésio/química , Masculino , Fosfatos/análise , Fosfatos/química , Estruvita , Cálculos Urinários/epidemiologia , Cálculos Urinários/veterinária
5.
Sci Rep ; 12(1): 7156, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35504903

RESUMO

Microalgae are a diverse group of microorganisms, the majority of which are photosynthetic in nature. Microalgae have different applications, the most important of which is the biological treatment of wastewater. Microalgae grow in various types of wastewater, such as wastewater polluted by Azo dyes, due to microalgae using wastewater as a culture medium, which contains many nutrients like nitrogen, phosphate, and carbon sources. Microalgae grow in various types of wastewater, such as wastewater polluted by Azo dyes, due to microalgae using wastewater as a culture medium, which contains many nutrients like nitrogen, phosphate, and carbon sources. So, microalgae are used for bioremediation of wastewater due to the efficiency of growing in wastewater and for the high production of lipids followed by trans-esterification to biodiesel. Face-centered central composite design (FCCCD) was used to determine the factors that have the most significant impact on the simultaneous decolorization of methyl red and lipid production by the fresh green alga Scenedesmus obliquus. The predicted results indicated that the alga decolorized 70.15% methyl red and produced 20.91% lipids by using 1 g/L nitrogen, an incubation time of 10 days, a pH of 8, and the concentration of methyl red is 17.65 mg/L. The dry biomasses of S. obliquus were also examined by SEM and FTIR before and after treatment with methyl red. SEM and FTIR showed that the properties of dry S. obliquus were altered after the biosorption of methyl red. According to GC-MS analysis of hexane extracts of S. obliquus, the lipid profile differed before and after methyl red decolorization. The results proved that it is possible to use S. obliquus to remove dyes and produce renewable fuels such as biodiesel. The novelty of this study is that this is the first time in which the effect of nitrogen concentrations in the medium used for algal growth on the removal of dye has been studied.


Assuntos
Clorofíceas , Microalgas , Scenedesmus , Compostos Azo , Biocombustíveis , Carbono , Ésteres , Ácidos Graxos , Nitrogênio , Fosfatos , Águas Residuárias/química
6.
Microbes Environ ; 37(2)2022.
Artigo em Inglês | MEDLINE | ID: mdl-35598988

RESUMO

Phosphorus (P) is abundant in soil and is essential for plant growth and development; however, it is easily rendered insoluble in complexes of different types of phosphates, which may lead to P deficiency. Therefore, increases in the amount of P released from phosphate minerals using microbial inoculants is an important aspect of agriculture. The present study used inorganic phosphate solubilizing bacteria (iPSB) in paddy field soils to develop microbial inoculants. Soils planted with rice were collected from different regions of Japan. Soil P was sequentially fractionated using the Hedley method. iPSB were isolated using selective media supplemented with tricalcium phosphate (Ca-P), aluminum phosphate (Al-P), or iron phosphate (Fe-P). Representative isolates were selected based on the P solubilization index and soil sampling site. Identification was performed using 16S rRNA and rpoB gene sequencing. Effectiveness was screened based on rice cultivar Koshihikari growth supplemented with Ca-P, Al-P, or Fe-P as the sole P source. Despite the relatively homogenous soil pH of paddy field sources, three sets of iPSB were isolated, suggesting the influence of fertilizer management and soil types. Most isolates were categorized as ß-Proteobacteria (43%). To the best of our knowledge, this is the first study to describe the genera Pleomorphomonas, Rhodanobacter, and Trinickia as iPSB. Acidovorax sp. JC5, Pseudomonas sp. JC11, Burkholderia sp. JA6 and JA10, Sphingomonas sp. JA11, Mycolicibacterium sp. JF5, and Variovorax sp. JF6 promoted plant growth in rice supplemented with an insoluble P source. The iPSBs obtained may be developed as microbial inoculants for various soil types with different P fixation capacities.


Assuntos
Inoculantes Agrícolas , Burkholderia , Oryza , Inoculantes Agrícolas/genética , Burkholderia/genética , Japão , Fosfatos , RNA Ribossômico 16S/genética , Solo/química , Microbiologia do Solo
7.
Open Vet J ; 12(2): 290-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603074

RESUMO

Background: Feline lower urinary tract disease (FLUTD) is a common disorder associated with the dysfunction of the urinary bladder or urethra in tomcats. Aim: A prospective study was carried out on the point prevalence and odds ratio (OR) of the FLUTD in Shirazi and Baladi tomcats at Ismailia Governorate, Egypt, recording the prominent clinical manifestation and identifying the antibiogram, virulence, and antimicrobial resistance genes of the causative microorganisms. Methods: A total number of 420 tomcats admitted to the veterinary clinics of Ismailia during the period June 2020 to May 2021 were examined for FLUTD. A total of 1,260 urine samples were collected and analyzed. Results: Hematuria, dysuria, and pollakiuria were the most evident signs recorded in a total of 120 tomcats diagnosed with FLUTD. The diagnosed cases of FLUTD were associated with causes like crystals (35.83%), pyogenic microorganisms (19.16%), and mixed cases (45.00%). The prevalence revealed highly significant (p < 0.01) increases in the cases caused by Escherichia coli, E. coli mixed cases, and calcium oxalate at >4 years; Staphylococcus aureus at ≤ 2 years; amorphous urate and phosphate at 2-4 and >4 years in Shirazi and ≤2 years in Baladi; triple phosphate at ≤2 years in Shirazi and >4 years in Baladi; and S. aureus mixed cases at ≤2 years. The OR of FLUTD revealed higher odds of associations with E. coli, E. coli mixed cases, S. aureus, amorphous urate, and triple phosphate, as well as lower odds with S. aureus, calcium oxalate, amorphous phosphate, and S. aureus mixed cases. Isolated E. coli revealed higher resistance to amoxicillin (AMX, 83.4%), ceftriaxone (83.4%), ceftazidime (CAZ, 75.0%), and cefoxitin (FOX, 50.0%), and S. aureus to oxacillin (100%), FOX (100%), AMX (85.8%), CAZ (76.2%), and FOX (50.0%). S. aureus-detected virulence genes were mecA, coa, spa, and tetK, and E. coli were fimH, iss, iutA, papC, blaTEM, blaCTX-M, and tetA. About 100% of E. coli and 76.1% of S. aureus isolates exhibited multidrug resistance. Conclusion: FLUTD in tomcats is associated with higher odds in E. coli, E. coli mixed cases, and triple phosphate at older ages (>4 years) with high antimicrobial resistance in the microbial isolates contributing to the disease.


Assuntos
Doenças do Gato , Doenças Urológicas , Animais , Oxalato de Cálcio , Doenças do Gato/epidemiologia , Gatos , Egito/epidemiologia , Escherichia coli , Fosfatos , Estudos Prospectivos , Staphylococcus aureus/genética , Ácido Úrico , Doenças Urológicas/veterinária
8.
J Virol Methods ; 305: 114539, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35523370

RESUMO

Epithelial tissue or vesicular fluid from an unruptured or recently ruptured vesicle is the sample of choice for confirmatory laboratory diagnosis of foot-and-mouth disease (FMD). However, in 'FMD-free' countries the transport and downstream processing of such samples from potentially infected animals present a biosafety risk, particularly during heightened surveillance, potentially involving decentralised testing in laboratories without adequate biocontainment facilities. In such circumstances, rapid inactivation of virus, if present, prior to transport becomes a necessity, while still maintaining the integrity of diagnostic analytes. Tongue epithelium collected from cattle infected with FMD virus (FMDV) of serotype O (O/ALG/3/2014 - Lineage O/ME-SA/Ind-2001d) or A (A/IRN/22/2015 - Lineage A/ASIA/G-VII) was incubated in the PAXGene Tissue System Fixative (pH 4) and Stabiliser (pH 6.5) components respectively, in McIlvaine's citrate-phosphate buffer (pH 2.6) or in phosphate-buffered saline (PBS, pH 7.4) at room temperature for 2, 6, 24 or 48 h. Following incubation, tissues were homogenised and tested by virus isolation and titration using LFBKαVß6 cells. The integrity of FMD viral RNA was assessed by RT-qPCR (3Dpol coding region), Sanger sequencing of the VP1 region and transfection of LFBKαVß6 cells to recover infectious virus. Viable virus could be recovered from samples incubated in PBS for at least 48 h. The PAXgene Tissue System Stabiliser component yielded variable results dependent on virus serotype, requiring at least 6 h of incubation to inactivate A/IRN/22/2015 in most samples, whereas the Fixative component required up to 2 h in some samples. McIlvaine's citrate-phosphate buffer rapidly inactivated both viruses within 2 h of incubation. There was no demonstrable degradation of FMD viral RNA resulting from incubation in any of the buffers for up to 48 h, as assessed by RT-qPCR, and 24 h by sequencing and transfection to recover infectious virus. McIlvaine's citrate-phosphate buffer (pH 2.6) is easy to prepare, inexpensive and inactivates serotype A and O FMDV in epithelial tissue within 2 h, while maintaining RNA integrity for downstream diagnostic processes and virus characterisation.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Bovinos , Citratos , Epitélio , Fixadores , Vírus da Febre Aftosa/genética , Fosfatos , RNA Viral/genética , Sorogrupo , Língua
9.
Water Res ; 218: 118467, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35525028

RESUMO

Decentralized treatment of human urine in sparsely populated regions could avoid the problem of sewage collection in traditionally centralized treatment schemes and simultaneously utilize the recovered N/P fertilizer in-situ to nurture gardens. Herein, an integrated electrochemical fixed bed packed with divided magnesite and carbon zones was constructed for the pretreatment of human urine, followed by the recovery of 95.0% NH4+ and 85.8% PO43- via struvite precipitation and NH3 volatilization as well as the on-site employment of the produced struvite as fertilizer. In the process, the acid/base zones created by electrochemical water splitting dissolved the magnesite filler as the Mg2+ source of struvite, further creating an ideal pH environment for struvite precipitation and NH3 volatilization in the effluent. Without the need to control solution pH by chemical addition, the system can resist impacts from changes in water quality by adjustment of the current density and flow rate, indicating its great potential for automatic operation. Life cycle assessment indicated that the on-site employment of produced struvite avoids the long-distance fertilizer transportation required for fertilization, thus reducing carbon emission by a hundred million tons per year if the household facility is driven by clean electricity.


Assuntos
Fertilizantes , Nitrogênio , Carbono , Precipitação Química , Humanos , Fosfatos , Fósforo , Estruvita
10.
J Environ Manage ; 315: 115157, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35526394

RESUMO

The discharge of excessive phosphate from wastewater sources into the aquatic environment has been identified as a major environmental threat responsible for eutrophication. It has become essential to develop efficient but affordable techniques to remove excess phosphate from wastewater before discharging into freshwater bodies. The use of metallic iron (Fe0) as a reactive agent for aqueous phosphate removal has received a wide attention. Fe0 in-situ generates positively charged iron corrosion products (FeCPs) at pH > 4.5, with high binding affinity for anionic phosphate. This study critically reviews the literature that focuses on the utilization of Fe0-based materials for aqueous phosphate removal. The fundamental science of aqueous iron corrosion and historical background of the application of Fe0 for phosphate removal are elucidated. The main mechanisms for phosphate removal are identified and extensively discussed based on the chemistry of the Fe0/H2O system. This critical evaluation confirms that the removal process is highly influenced by several operational factors including contact time, Fe0 type, influent geochemistry, initial phosphate concentration, mixing conditions, and pH value. The difficulty in comparing independent results owing to diverse experimental conditions is highlighted. Moreover, contemporary research in progress including Fe0/oxidant systems, nano-Fe0 application, Fe0 material selection, desorption studies, and proper design of Fe0-based systems for improved phosphate removal have been discussed. Finally, potential strategies to close the loop in Fe0-based phosphate remediation systems are discussed. This review presents a science-based guide to optimize the efficient design of Fe0-based systems for phosphate removal.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Ferro , Fosfatos , Águas Residuárias , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
11.
BMC Nephrol ; 23(1): 162, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484519

RESUMO

BACKGROUND: The progression of chronic kidney disease (CKD) is associated with an increasing risk of cardiovascular morbidity and mortality due to elevated serum phosphate levels. Besides low phosphate diets and hemodialysis, oral phosphate binders are prescribed to treat hyperphosphatemia in CKD patients. This study reports on a processed clay mineral as a novel and efficient phosphate sorbent with comparable efficacy of a clinically approved phosphate binder. METHODS: 5/6 nephrectomized rats, which develop chronic renal failure (CRF), received a high phosphate and calcium diet supplemented with either a processed Montmorillonite-Illite clay mineral (pClM) or lanthanum carbonate (LaC) for 12 weeks. Levels of plasma uremic toxins, glomerular filtration rates and microalbuminuria were determined and the histomorphology of blood vessels and smooth muscle cells was analyzed. RESULTS: 5/6 nephrectomy induced an increase in plasma uremic toxins levels and progressive proteinuria. Treatment of CRF rats with pClM decreased observed vascular pathologies such as vascular fibrosis, especially in coronary vessels. The transition of vascular smooth muscle cells from a contractile to a secretory phenotype was delayed. Moreover, pClM administration resulted in decreased blood creatinine and urea levels, and increased glomerular filtration rates, reduced microalbuminuria and eventually the mortality rate in CRF rats. CONCLUSION: Our study reveals pClM as a potent phosphate binding agent with beneficial impacts on pathophysiological processes in an animal model of CKD. pClM effectively attenuates the progression of vascular damage and loss of renal function which are the most severe consequences of chronic renal failure.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Albuminúria/complicações , Animais , Argila , Feminino , Humanos , Falência Renal Crônica/complicações , Masculino , Minerais , Fosfatos , Ratos , Insuficiência Renal Crônica/complicações
13.
Drug Des Devel Ther ; 16: 931-950, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35391788

RESUMO

Background: Abnormal sphingolipid metabolism is closely related to the occurrence and development of Alzheimer's disease (AD). With heat-clearing and detoxifying effects, Huanglian Jiedu decoction (HLJDD) has been used to treat dementia and improve learning and memory impairments. Purpose: To study the therapeutic effect of HLJDD on AD as it relates to sphingolipid metabolism. Methods: The level of sphingolipids in the brains of APP/PS1 mice and in the supernatant of ß-amyloid (Aß)25-35-induced BV2 microglia was detected by HPLC-QTOF-MS and HPLC-QTRAP-MS techniques, respectively. The co-expression of ionized calcium-binding adapter molecule 1 (Iba1) and Aß as well as four enzymes related to sphingolipid metabolism, including serine palmitoyltransferase 2 (SPTLC2), cer synthase 2 (CERS2), sphingomyelin phosphodiesterase 1 (SMPD1), and sphingomyelin synthase 1 (SGMS1), in the brains of APP/PS1 mice were evaluated by immunofluorescence double labelling. In addition, real-time quantitative reverse transcription-polymerase chain reaction was conducted to determine the mRNA expression of SPTLC2, CERS2, SMPD1, SGMS1, galactosylceramidase (GALC), and sphingosine kinase 2 (SPHK2) in Aß25-35-stimulated BV2 microglia. Results: Abnormal sphingolipid metabolism was observed both in APP/PS1 mouse brain tissues and Aß25-35-stimulated BV2 cells. The levels of sphingosine, sphinganine, sphingosine-1-phosphate, sphinganine-1-phosphate and sphingomyelin were significantly reduced, while the levels of ceramide-1-phosphate, ceramide, lactosylceramide and hexosylceramide significantly increased in Aß25-35-stimulated BV2 cells. In AD mice, more microglia were clustered in the Aß-positive region. The decreased level of SGMS1 and increased levels of CERS2, SPTLC and SMPD1 were also found. In addition, the expressions of SPTLC2, CERS2, and SMPD1 in Aß25-35-stimulated BV2 cells were increased significantly, while the expressions of GALC, SPHK2, and SGMS1 were decreased. These changes all showed a significant correction after HLJDD treatment. Conclusion: HLJDD is a good candidate for treating AD. This study provides a novel perspective on the potential roles of the sphingolipid metabolism in AD.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Ceramidas/metabolismo , Ceramidas/uso terapêutico , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas , Camundongos , Camundongos Transgênicos , Microglia/metabolismo , Fosfatos/uso terapêutico , Esfingolipídeos
14.
Int J Mol Sci ; 23(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408807

RESUMO

Glyoxal (GO) and methylglyoxal (MGO) are highly reactive species formed in carbohydrate metabolism. Nε-Carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL) are considered to be the advanced glycation end-products (AGEs) of L-lysine (Lys) with GO and MGO, respectively. Here, we investigated the reaction of free L-lysine (Lys) with GO and MGO in phosphate buffer (pH 7.4) at 37 °C and 80 °C in detail in the absence of any other chemicals which are widely used to reduce Schiff bases. The concentrations of Lys, GO and MGO used in the experiments were 0.5, 2.5, 5.0, 7.5 and 10 mM. The reaction time ranged between 0 and 240 min. Experiments were performed in triplicate. The concentrations of remaining Lys and of CML and CEL formed in the reaction mixtures were measured by stable-isotope dilution gas chromatography-mass spectrometry (GC-MS). Our experiments showed that CML and CEL were formed at higher concentrations at 80 °C compared to 37 °C. CML was found to be the major reaction product. In mixtures of GO and MGO, MGO inhibited the formation of CML from Lys (5 mM) in a concentration-dependent manner. The highest CML concentration was about 300 µM corresponding to a reaction yield of 6% with respect to Lys. An addition of Lys to GO, MGO and their mixtures resulted in strong reversible decreases in the Lys concentration up to 50%. It is assumed that free Lys reacts rapidly with GO and MGO to form many not yet identified reaction products. Reaction mixtures of Lys and MGO were stronger colored than those of Lys and GO, notably at 80 °C, indicating higher reactivity of MGO towards Lys that leads to polymeric colored MGO species. We have a strong indication of the formation of Nε-(hydroxymethyl)-lysine (HML) as a novel reaction product of Lys methyl ester with MGO. A mechanism is proposed for the formation of HML from Lys and MGO. This mechanism may explain why Lys and GO do not react to form a related product. Preliminary analyses show that HML is formed at higher concentrations than CEL from Lys methyl ester and MGO. No Schiff bases or their hydroxylic precursors were identified as reaction products. In their reactions with Lys, GO and MGO are likely to act both as chemical oxidants on the terminal aldehyde group to a carboxylic group (i.e., R-CHO to R-COOH) and as chemical reductors on labile Schiff bases (R-CH=N-R to R-CH2-NH-R) presumably via disproportionation and hydride transfer. Our study shows that free non-proteinic Lys reacts with GO and MGO to form CML, CEL and HML in very low yield. Whether proteinic Lys also reacts with MGO to form HML residues in proteins remains to be investigated. The physiological occurrence and concentration of HML in biological fluids and tissues and its relation to CML and CEL are elusive and warrant further investigations in health and disease. Chemical synthesis and structural characterization of HML are expected to advance and accelerate the scientific research in this topic.


Assuntos
Glioxal , Aldeído Pirúvico , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Produtos Finais de Glicação Avançada/química , Concentração de Íons de Hidrogênio , Lisina/análogos & derivados , Lisina/análise , Óxido de Magnésio , Fosfatos , Aldeído Pirúvico/química , Bases de Schiff
15.
J Oral Sci ; 64(2): 167-171, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370182

RESUMO

PURPOSE: This study compared the bond strengths of four adhesive systems and four different resin composite block materials: Gradia Block (GR), Shofu Block HC (SH), Estelite Block (ES), and KZR-CAD HR2 (KZ). METHODS: A primer (PZ-AB) containing a silane (γ-MPTS) with 10-methacryloyloxydecyl dihydrogen phosphate (MDP) was applied to ground surfaces of the resin composite block specimens, and the specimens were then bonded to stainless-steel rods using two methyl methacrylate-tributylborane (MMA-TBB)-based luting agents (SB and MT), designated as the PZ-AB/SB and PZ-AB/MT adhesive systems, respectively. The SB resin contained 4-methacryloyloxyethyl trimellitate anhydride (4-META), whereas the MT resin did not. The SB resin without primer (No primer/SB) and a dual-curing composite-type adhesive system (UPA/RelyX) were used as controls. The 24-h tensile bond strengths were determined and analyzed using the Tukey-Kramer HSD test (α = 0.05, n = 8). RESULTS: The highest bond strengths were obtained for the GR/PZ-AB/MT, GR/PZ-AB/SB, KZ/PZ-AB/MT, ES/PZ-AB/SB, and KZ/No primer/SB groups, whereas the KZ/UPA/RelyX, ES/UPA/RelyX, SH/UPA/RelyX, and SH/No primer/SB groups exhibited the lowest bond strengths. CONCLUSION: For each resin composite block material primed with γ-MPTS and MDP, the MMA-TBB-based luting agents, irrespective of the presence of 4-META, provided higher bond strengths than the dual-curing composite-type adhesive system.


Assuntos
Colagem Dentária , Cimentos Dentários , Compostos de Boro , Cimentos Dentários/química , Teste de Materiais , Metacrilatos/química , Metilmetacrilato/química , Fosfatos , Silanos/química
16.
BMC Mol Cell Biol ; 23(1): 17, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35399070

RESUMO

BACKGROUND: We have previously found that, in the pathogenic yeast Candida albicans, 18S and 25S ribosomal RNA components, containing more than one phosphate on their 5'-end were resistant to 5'-monophosphate requiring 5' → 3″ exonuclease. Several lines of evidence pointed to RNAP II as the enzyme producing them. RESULTS: We now show the production of such 18S and 25S rRNAs in Saccharomyces cerevisiae that have been permanently switched to RNAP II (due to deletion of part of RNAP I upstream activator alone, or in combination with deletion of one component of RNAP I itself). They contain more than one phosphate at their 5'-end and an anti-cap specific antibody binds to them indicating capping of these molecules. These molecules are found in RNA isolated from nuclei, therefore are unlikely to have been modified in the cytoplasm. CONCLUSIONS: Our data confirm the existence of such molecules and firmly establish RNAP II playing a role in their production. The fact that we see these molecules in wild type Saccharomyces cerevisiae indicates that they are not only a result of mutations but are part of the cells physiology. This adds another way RNAP II is involved in ribosome production in addition to their role in the production of ribosome associated proteins.


Assuntos
RNA Polimerase II , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Exonucleases/metabolismo , Fosfatos/metabolismo , RNA Polimerase II/metabolismo , RNA Ribossômico/genética , RNA Ribossômico 18S , Proteínas Ribossômicas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
17.
Front Endocrinol (Lausanne) ; 13: 866170, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35399930

RESUMO

Background: Gait deviations, lower limb pain and joint stiffness represent key symptoms in patients with X-linked hypophosphatemia (XLH, OMIM 307800), a rare disorder of mineral homeostasis. While the pathomechanism for rickets is well understood, the direct role of PHEX (Phosphate-regulating neutral endopeptidase) deficiency in non-rachitic features including complex deformities, skull and dental affections remains unclear. FGF23-inhibiting antibody treatment can normalize serum phosphate levels and to improve rickets in XLH patients. However, linear growth remains impaired and effects on lower limb deformity and gait are insufficiently studied. Aims: To characterize and evaluate the course of lower limb deformity in a case series of pediatric XLH patients receiving Burosumab therapy. Methods: Comparative assessment of planar radiographs, gait analysis, biochemical and clinical features of pediatric patients before and ≥12 months after initiation of FGF23-inhibiting was performed prospectively. Lower limb maltorsion was quantified by torsional MRI and gait analysis. Standardized deformity analysis of lower limb anteroposterior radiographs was conducted. Results: Seven patients (age 9.0 +/-3.6 years) were eligible for this study. All patients received conventional treatment before onset of antibody treatment. Maltorsion of the femur was observed in 8/14 legs using torsional MRI (mean antetorsion 8.79°). Maltorsion of the tibia was observed in 9/14 legs (mean external torsion 2.8°). Gait analysis confirmed MRI findings with femoral external malrotation prior to and one year after onset of Burosumab therapy. Internal foot progression (intoeing gait) remained pathological in all cases (mean 2.2°). Knee rotation was pathologically internal 10/14 legs. Mean mechanical axis deviation (MAD) of 16.1mm prior to Burosumab changed in average by 3.9mm. Three children underwent guided growth procedures within the observation period. Mild postprocedural rebound of frontal axis deviation was observed under Burosumab treatment in one patient. Conclusions: This is the first study to investigate lower limb deformity parameters quantitatively in children with XLH receiving Burosumab. One year of Burosumab therapy was associated with persistent maltorsion and frontal axis deviation (varus/valgus) despite improved rickets in this small, prospective uncontrolled study.


Assuntos
Raquitismo Hipofosfatêmico Familiar , Extremidade Inferior , Criança , Raquitismo Hipofosfatêmico Familiar/complicações , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Fatores de Crescimento de Fibroblastos , Humanos , Extremidade Inferior/patologia , Fosfatos , Estudos Prospectivos
18.
ACS Appl Mater Interfaces ; 14(15): 17153-17163, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35394283

RESUMO

Tumor microenvironment (TME)-responsive chemodynamic therapy (CDT) mediated by nanozymes has been extensively studied both experimentally and theoretically, but the low catalytic efficiency due to insufficient H2O2 in the TME and the poor biodegradability of the nanozymes are still main challenges for clinical translation of nanozymes. Herein, we designed a H2O2 self-supplying nanozyme bearing glucose oxidase (GOX) and polyethyleneimine based on a degradable iron-doped phosphate-based glass (FePBG) nanomimic (FePBG@GOX), which can convert endogenous glucose into toxic hydroxyl radicals. The GOX loaded on the nanozyme can effectively consume glucose in tumor cells to produce a large amount of H2O2 to make up for the lack of H2O2 in the TME. Thereafter, enormous hydroxyl radicals, based on a Fenton reaction of FePBG without any exogenous H2O2, are generated to induce severe apoptosis of tumor cells. The nanozyme exhibits enhanced in vitro cytotoxicity in a high-glucose medium than in a low-glucose medium, illustrating sufficient generation of H2O2 by GOX. The excellent in vivo antitumor efficacy is manifested by a high tumor growth inhibition ratio of 94.65% in model mice. Excellent intrinsic biodegradability owing to its phosphate-based glass nature is a remarkable advantage of the prepared FePBG nanozyme over most other reported nanozymes. Big concerns about side effects caused by long-time residence in living organisms are eliminated since it degrades not only in an acid medium but also in a neutral physiological environment. Therefore, this novel strategy of the TME-responsive H2O2 self-supplying nanozyme based on an endogenous cascade catalytic reaction opens up an avenue for designing degradable nanozymes in CDT.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Animais , Linhagem Celular Tumoral , Glucose , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila , Ferro , Camundongos , Neoplasias/tratamento farmacológico , Fosfatos , Microambiente Tumoral
19.
Hum Genomics ; 16(1): 13, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35443721

RESUMO

BACKGROUND: Variants in SLC34A2 encoding the sodium-dependent phosphate transport protein 2b (NaPi-IIb) cause the rare lung disease pulmonary alveolar microlithiasis (PAM). PAM is characterised by the deposition of calcium-phosphate concretions in the alveoli usually progressing over time. No effective treatment is available. So far, 30 allelic variants in patients have been reported but only a few have been functionally characterised. This study aimed to determine the impact of selected SLC34A2 variants on transporter expression and phosphate uptake in cellular studies. METHODS: Two nonsense variants (c.910A > T and c.1456C > T), one frameshift (c.1328delT), and one in-frame deletion (c.1402_1404delACC) previously reported in patients with PAM were selected for investigation. Wild-type and mutant c-Myc-tagged human NaPi-IIb constructs were expressed in Xenopus laevis oocytes. The transport function was investigated with a 32Pi uptake assay. NaPi-IIb protein expression and localisation were determined with immunoblotting and immunohistochemistry, respectively. RESULTS: Oocytes injected with the wild-type human NaPi-IIb construct had significant 32Pi transport compared to water-injected oocytes. In addition, the protein had a molecular weight as expected for the glycosylated form, and it was readily detectable in the oocyte membrane. Although the protein from the Thr468del construct was synthesised and expressed in the oocyte membrane, phosphate transport was similar to non-injected control oocytes. All other mutants were non-functional and not expressed in the membrane, consistent with the expected impact of the truncations caused by premature stop codons. CONCLUSIONS: Of four analysed SLC34A2 variants, only the Thr468del showed similar protein expression as the wild-type cotransporter in the oocyte membrane. All mutant transporters were non-functional, supporting that dysfunction of NaPi-IIb underlies the pathology of PAM.


Assuntos
Calcinose , Pneumopatias , Mutação da Fase de Leitura , Doenças Genéticas Inatas , Humanos , Pneumopatias/genética , Fosfatos , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIb/genética
20.
Cardiovasc Diabetol ; 21(1): 61, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477475

RESUMO

INTRODUCTION: Individuals with type 2 diabetes have a substantially elevated cardiovascular risk. A higher plasma phosphate level promotes vascular calcification, which may adversely affect outcomes in individuals with type 2 diabetes. We hypothesized that the association between plasma phosphate and all-cause mortality is stronger in individuals with type 2 diabetes, compared to those without diabetes. METHODS: We analysed the association between plasma phosphate and all-cause mortality in the Dutch population-based Lifelines cohort and in subgroups with and without type 2 diabetes, using multivariable Cox regression adjusted for potential confounders. Effect modification was tested using multiplicative interaction terms. RESULTS: We included 57,170 individuals with 9.4 [8.8-10.4] years follow-up. Individuals within the highest phosphate tertile (range 1.00-1.83 mmol/L) were at higher risk of all-cause mortality (fully adjusted HR 1.18 [95% CI 1.02-1.36], p = 0.02), compared with the intermediate tertile (range 0.85-0.99 mmol/L). We found significant effect modification by baseline type 2 diabetes status (p-interaction = 0.003). Within the type 2 diabetes subgroup (N = 1790), individuals within the highest plasma phosphate tertile had an increased mortality risk (HR 1.73 [95% CI 1.10-2.72], p = 0.02 vs intermediate tertile). In individuals without diabetes at baseline (N = 55,380), phosphate was not associated with mortality (HR 1.12 [95% CI 0.96-1.31], p = 0.14). Results were similar after excluding individuals with eGFR < 60 mL/min/1.73 m2. DISCUSSION: High-normal plasma phosphate levels were associated with all-cause mortality in individuals with type 2 diabetes. The association was weaker and non-significant in those without diabetes. Measurement of phosphate levels should be considered in type 2 diabetes; whether lowering phosphate levels can improve health outcomes in diabetes requires further study.


Assuntos
Diabetes Mellitus Tipo 2 , Calcificação Vascular , Estudos de Coortes , Humanos , Fosfatos , Calcificação Vascular/complicações
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