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1.
Acta Neurol Belg ; 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38583111

RESUMO

BACKGROUND: The article discusses the investigations into the nucleus of Perlia (NP), a spindle-shaped nucleus located in the dorsal aspect of the oculomotor complex. However, there is still debate over its exact location and function, with conflicting findings in nonhuman primates. Therefore, the current study aimed the describe the location, function, clinical and surgical implications of NP. METHODS: A systematic review was conducted to identify studies related to the following MeSH terms: "perlia nucleus" OR "nucleus of "perlia" OR "convergence nucleus" OR "nucleus of convergence" OR "Perlia's nucleus". The search was conducted until September 2022. RESULTS: The location of the NP has been consistently reported in various studies, with most describing it as situated ventral to the Edinger-Westphal nucleus (EW) and dorsomedial to the oculomotor complex. The incidence of the NP in humans has been reported to range from 9 to 40%. In primates, it was observed to be absent in 77% of midbrains, while well developed in 9%. It is also noted that the NP is not a single nucleus, but rather a group of nuclei that are interconnected and involved in the coordination of eye movements that contain parasympathetic neurons. CONCLUSIONS: The study of the NP holds clinical implications for understanding the neural mechanisms underlying the irregularities in the pupillary light reflex, such as anisocoria or abnormal responses to light, diagnosis, and treatment of neurological disorders like Horner's syndrome, and management of eye movement disorders including one-and-a-half syndrome, vertical gaze palsy, skew deviation and ptosis. The current study also highlighted the limitations of previous studies, including variations in the reported prevalence of the NP, limitations of the histological techniques, and inconsistent findings across human and animal studies.

2.
Enzyme Microb Technol ; 162: 110137, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36274425

RESUMO

Fish consumption is essential for a healthy diet. However, all seafood including fish are susceptible to deterioration unless properly preserved. Controlling the freshness of fresh or packaged fish is a challenging issue for the food industry in terms of human health and shelf life determination. One of the main indicators showing the freshness of fish is undoubtedly the amount of hypoxanthine (Hx). As soon as the organism dies, Hx begins to be released with the cessation of ATP synthesis and shows a gradual increase over time. Therefore, Hx determination is an important indicator in the control of fish freshness. Based on this fact, a colorimetric method for the enzymatic determination of Hx using the CUPRAC (Cupric ion Reducing Antioxidant Capacity) sensor was developed. Uric acid (UA) and H2O2 are enzymatically produced by xanthine oxidase (XOD) from Hx, and both products respond to the CUPRAC reagent to produce the cuprous neocuproine (Cu(I)-Nc) chromophore chelate formed in situ on a Nafion anionic membrane on which the cationic Cu(II)-Nc complex was fixed. Hx was measured at different time intervals in the meat samples taken from sea bass (Dicentrarchus labrax), which was left to stand at room temperature for a time period between 0 and 24 h; the level of spoilage was determined from the coloration of the CUPRAC membrane sensor (via absorbance measurement at 450 nm). It was observed that there was a linear increase in the amount of Hx during the measurement period. The method was optimized for Hx determination, verified with interference analysis and standard additions to real samples, and validated against HPLC. The linear detection range of the developed method for Hx was 2.0-32.0 µM with an LOD of 0.79 µM, and early stages of fish degradation could be detected at several nanomoles of Hx per gram of fish meat. The proposed method was demonstrated to have distinct superiority over many recent colorimetric sensors of fish freshness in regard to its lower LOD for Hx, wider linear range, capability to cope with interferents (including biologically important antioxidants, such as cysteine, reduced glutathione, ascorbic acid, UA and α-tocopherol) and applicability to real samples.


Assuntos
Colorimetria , Peróxido de Hidrogênio , Animais , Humanos , Hipoxantina/análise , Antioxidantes/metabolismo , Ácido Ascórbico , Ácido Úrico/análise
3.
JACC Case Rep ; 4(5): 318-320, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35257111

RESUMO

Blood flow and shear stresses were quantified using 4-dimensional flow cardiac magnetic resonance and 3-dimensional particle velocimetry before and after transcatheter aortic valve replacement (TAVR). TAVR reduced turbulent kinetic energy by 47% and shear stresses by 33%, illustrating that the benefit of TAVR extends beyond a simple reduction in transvalvular gradients. (Level of Difficulty: Advanced.).

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 260: 119941, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34034074

RESUMO

Even though sulfate anion radical (SO4-) is a very reactive oxidant used in advanced oxidation processes, a reliably selective and simple colorimetric method for determining this radical can hardly be found. Peroxydisulfate (S2O82-) or peroxymonosulfate (HSO5-) can be activated with transition metal ions to produce SO4-. We have discovered that Cr(III) can be an activator for persulfate, generating Cr(VI) along with SO4-. By measuring the emerging chromate with diphenyl carbazide (DPC) spectrophotometry at 542 nm, we could measure both the formation of SO4- and its scavenging with antioxidant compounds. We could also investigate a number of UV-absorbing SO4- scavengers which could not be measured with other UV spectrometric methods. In addition to conventional antioxidants (phenolics such as quercetin, catechin, epicatechin, caffeic acid, thiols like cysteine and N-acetyl cysteine, and ascorbid acid), nitro-aromatics (represented by 2,4,6-trinitrophenol and 2,4-dinitrophenol) used in ammunition formulations could also be measured as scavengers. The presence of scavengers caused a reduction in the amount of Cr(VI) generated, where the difference in absorbance (ΔA) of chromate - with respect to the DPC method - in the absence and presence of scavengers was a linear function of SO4- scavenging capacity. Ethanol and tert-butanol were tested as solvents to show the selectivity of the method for SO4-. The method was statistically compared to a suitably modified ABTS/persulfate assay. The efficiency order of sulfate radical scavengers was determined and ranked (Spearman's test) using both the proposed method and modified ABTS/persulfate method to reveal a moderate correlation.

5.
J Chromatogr Sci ; 59(4): 325-337, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33313763

RESUMO

This study was carried out to determine the main pigments in some different selected seaweeds and to reveal their antioxidant potential regarding the ever-increasing demand for utilization of marine pigments in human health and nutrition. The individual amounts of algal pigments were found by reverse phase high-performance liquid chromatography (HPLC) and their total antioxidant capacities (TAC) by two spectrophotometric TAC assays, namely: CUPRAC (CUPric ion Reducing Antioxidant Capacity) and ABTS/TEAC (2,2'-azinobis [3-ethyl benzo thiazoline-6-sulfonate])/(trolox equivalent antioxidant capacity). These two tests gave the same rank order for TAC. The TAC of HPLC-quantified compounds accounted for a relatively much lower percentage of the observed CUPRAC capacities of seaweed extracts, namely ranging from 11 to 68% for brown, from 4 to 41% for red and from 3 to 100% for green species, i.e., some TAC originated from chromatographically unidentified compounds. Fucoxanthin, chlorophyll a, and pheophytin a compounds were major pigments in brown algae. The relative carotenoid contents in red marine algae were generally lower than those of chlorophylls. Overall total quantities were quite low compared with those of brown species. In general, chlorophyll a and chlorophyll b were chiefly present in green algae, but ß-carotene, violaxanthin and siphonaxanthin were also detected substantially higher in some species of green algae such as Caulerpa racemosa var. cylindracea and Codium fragile.


Assuntos
Antioxidantes/análise , Clorófitas/química , Phaeophyceae/química , Pigmentos Biológicos/química , Rodófitas/química , Carotenoides/análise , Clorofila/análise , Cromatografia Líquida de Alta Pressão/métodos , Modelos Lineares , Extratos Vegetais/química
6.
J Chromatogr Sci ; 58(2): 98-108, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31681954

RESUMO

Analysis of plant growth regulators (PGRs) should be approached by considering their extremely low concentrations and serious interfering effects that result from the matrix of various plant tissues. In the current research, the separation and simultaneous determination of different classes of phytohormones in 14 seaweeds collected from Turkey seashores were achieved by using solid-phase extraction (SPE) followed by a rapid and sensitive liquid chromatography tandem mass detection method. OASIS HLB (Hydrophilic-Lipophilic Balance) cartridges were successfully used for SPE process to eliminate the matrix effect and enhance the PGRs including zeatin, benzyl amino purine, indole-3-acetic acid, abscisic acid and gibberellic acid within partially different polarities. Based on the optimized experimental conditions, the method presented excellent performance related to linearity (r, 0.9996-0.9999) within the ranges of 0.5-500 ng/mL, relative standard deviation values ((1.43-2.01) for intraday and (2.36-3.50) for interday)), the limit of detection (0.01-0.84 µg/L) and the limit of quantification (0.02-2.76 µg/L). The obtained results confirm that the SPE-liquid chromatography/tandem mass spectrometry method performed is highly effective and convenient for routine analyses of trace amounts of the tested phytohormones in seaweeds and any other plant samples as well.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Alga Marinha/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Turquia
7.
Genet Mol Biol ; 33(4): 719-30, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21637582

RESUMO

Expressed sequence tag (EST) markers have been used to assess variety and genetic diversity in wheat (Triticum aestivum). In this study, 1549 ESTs from wheat infested with yellow rust were used to examine the genetic diversity of six susceptible and resistant wheat cultivars. The aim of using these cultivars was to improve the competitiveness of public wheat breeding programs through the intensive use of modern, particularly marker-assisted, selection technologies. The F(2) individuals derived from cultivar crosses were screened for resistance to yellow rust at the seedling stage in greenhouses and adult stage in the field to identify DNA markers genetically linked to resistance. Five hundred and sixty ESTs were assembled into 136 contigs and 989 singletons. BlastX search results showed that 39 (29%) contigs and 96 (10%) singletons were homologous to wheat genes. The database-matched contigs and singletons were assigned to eight functional groups related to protein synthesis, photosynthesis, metabolism and energy, stress proteins, transporter proteins, protein breakdown and recycling, cell growth and division and reactive oxygen scavengers. PCR analyses with primers based on the contigs and singletons showed that the most polymorphic functional categories were photosynthesis (contigs) and metabolism and energy (singletons). EST analysis revealed considerable genetic variability among the Turkish wheat cultivars resistant and susceptible to yellow rust disease and allowed calculation of the mean genetic distance between cultivars, with the greatest similarity (0.725) being between Harmankaya99 and Sönmez2001, and the lowest (0.622) between Aytin98 and Izgi01.

8.
Genet. mol. biol ; 33(4): 719-730, 2010.
Artigo em Inglês | LILACS | ID: lil-571524

RESUMO

Expressed sequence tag (EST) markers have been used to assess variety and genetic diversity in wheat (Triticum aestivum). In this study, 1549 ESTs from wheat infested with yellow rust were used to examine the genetic diversity of six susceptible and resistant wheat cultivars. The aim of using these cultivars was to improve the competitiveness of public wheat breeding programs through the intensive use of modern, particularly marker-assisted, selection technologies. The F2 individuals derived from cultivar crosses were screened for resistance to yellow rust at the seedling stage in greenhouses and adult stage in the field to identify DNA markers genetically linked to resistance. Five hundred and sixty ESTs were assembled into 136 contigs and 989 singletons. BlastX search results showed that 39 (29 percent) contigs and 96 (10 percent) singletons were homologous to wheat genes. The database-matched contigs and singletons were assigned to eight functional groups related to protein synthesis, photosynthesis, metabolism and energy, stress proteins, transporter proteins, protein breakdown and recycling, cell growth and division and reactive oxygen scavengers. PCR analyses with primers based on the contigs and singletons showed that the most polymorphic functional categories were photosynthesis (contigs) and metabolism and energy (singletons). EST analysis revealed considerable genetic variability among the Turkish wheat cultivars resistant and susceptible to yellow rust disease and allowed calculation of the mean genetic distance between cultivars, with the greatest similarity (0.725) being between Harmankaya99 and Sönmez2001, and the lowest (0.622) between Aytin98 and Izgi01.

9.
Acta Biol Hung ; 60(3): 309-19, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19700390

RESUMO

In this study, induction of regenerable callus from mature embryos in eight Turkish barley varieties was analysed by using different plant growth regulators (PGRs). Varying concentrations (0.5-4 mg l -1 ) of 2,4-dichlorophenoxyacetic acid (2,4-D) and dicamba (3,6-dichloro-o-anisic acid) were tested for callus induction from mature embryos. Highest percent of callus induction was observed in Bornova 92 variety (98.3%) on MS medium supplemented with 4 mg l -1 dicamba. Calli were transferred to regeneration media with 0.5 mg l -1 dicamba, 0.5 mg l -1 zeatin riboside (ZR) and 2 mg l -1 thidiazuron (TDZ). Low concentrations of dicamba induced multiple shoots during callus regeneration. When the effect of precultivation with 2,4-D or dicamba on the shoot induction were evaluated, lower concentrations (< 4 mg l -1 ) of auxins have been found optimal. On the regeneration medium with 0.5 mg l -1 dicamba, shoots were able to elongate up to 20 cm and shoot numbers were between 1-23 per callus. The use of ZR led to formation of short shoot buds and somatic embryos in 2 weeks period. The effect of TDZ was different from other PGRs by inducing green solid sectors on calli surfaces (Total 51 sectors/20 callus/Akhisar variety). Five plantlets have been grown from these solid cell clumps and transferred to specific media for root formation. As a result, five varieties (Süleyman Bey, Bornova 92, Vamyk Hoca, Kaya and Akhisar) tested in our study showed the potential to produce regenerable callus by using low amounts of dicamba or TDZ. The optimization process starts from culturing embryos to plantlet formation took nearly 4 weeks.


Assuntos
Hordeum/fisiologia , Regeneração , Sementes/fisiologia , Proliferação de Células/efeitos dos fármacos , Genótipo , Hordeum/efeitos dos fármacos , Hordeum/embriologia , Reguladores de Crescimento de Plantas/farmacologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos
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