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1.
Int Microbiol ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740652

RESUMO

The gills and skin microbiota and microbiome of wild fish remain far more under-investigated compared to that of farmed fish species, despite that these animal-microbe interactions hold the same ecophysiological roles in both cases. In this study, the gills and skin bacterial microbiota profiles and their presumptive bacterial metabolisms were investigated in five open-sea fishes: bullet tuna (Auxis sp.), common dolphinfish (Coryphaena hippurus), Atlantic little tunny (Euthynnus alletteratus), Atlantic bonito (Sarda sarda) and Atlantic white marlin (Kajikia albida). Gills and skin tissues were collected from two to three individuals per species, from specimens caught by recreational trolling during summer of 2019, and their bacterial 16S rRNA gene diversity was analysed by high-throughput sequencing. The gills bacterial communities among the five species were clearly different but not the skin bacterial microbiota. The dominant operational taxonomic units belonged to the Moraxellaceae, Pseudomonadaceae, Rhodobacteraceae, Staphylococcaceae and Vibrionaceae families. Despite the differences in taxonomic composition, the presumptive bacterial metabolisms between the gills and skin of the five fishes investigated here were ≥ 94% similar and were dominated by basic metabolism, most likely reflecting the continuous exposure of these tissues in the surrounding seawater.

2.
Arch Pharm (Weinheim) ; 357(6): e2300663, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38408265

RESUMO

The Cucurbita genus has been widely used in traditional medicinal systems across different countries. In this study, we aimed to investigate the chemical composition, antioxidant properties, enzyme inhibitory, and cytotoxic effects of methanol and aqueous extracts obtained from the aerial parts, seeds, and fruit shells of Cucurbita okeechobeensis. Antioxidant properties were assessed using various chemical methods, including radical quenching (DPPH and ABTS), reducing power (CUPRAC and FRAP), metal chelation, and phosphomolybdenum assays. The extracts' enzyme inhibitory effects were tested against cholinesterase, amylase, glucosidase, and tyrosinase, whereas different cancer cell lines were used for the cytotoxicity study. The chemical composition, evaluated by HPLC-ESI-MSn, showed that the most abundant compounds were flavonoids (mainly quercetin glycosides) followed by phenolic acids (mostly caffeic acid derivatives). The aerial parts displayed stronger antioxidant ability than the seed and fruit shells, in agreement with the highest content in phytochemicals. In addition, the methanol extracts presented the highest bioactivity and content in phytochemicals; among them, the extract of the aerial part exhibited significant cytotoxic effects on cancer cell lines and induced apoptosis. Overall, our results suggest that C. okeechobeensis is a valuable source of bioactive compounds for the pharmaceutical and nutraceutical industries.


Assuntos
Antineoplásicos Fitogênicos , Antioxidantes , Cucurbita , Frutas , Componentes Aéreos da Planta , Extratos Vegetais , Sementes , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Humanos , Sementes/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cucurbita/química , Componentes Aéreos da Planta/química , Frutas/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Cromatografia Líquida de Alta Pressão
3.
Ann Neurol ; 92(4): 562-573, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689346

RESUMO

OBJECTIVE: Cerebral venous thrombosis (CVT) caused by vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare adverse effect of adenovirus-based severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccines. In March 2021, after autoimmune pathogenesis of VITT was discovered, treatment recommendations were developed. These comprised immunomodulation, non-heparin anticoagulants, and avoidance of platelet transfusion. The aim of this study was to evaluate adherence to these recommendations and its association with mortality. METHODS: We used data from an international prospective registry of patients with CVT after the adenovirus-based SARS-CoV-2 vaccination. We analyzed possible, probable, or definite VITT-CVT cases included until January 18, 2022. Immunomodulation entailed administration of intravenous immunoglobulins and/or plasmapheresis. RESULTS: Ninety-nine patients with VITT-CVT from 71 hospitals in 17 countries were analyzed. Five of 38 (13%), 11 of 24 (46%), and 28 of 37 (76%) of the patients diagnosed in March, April, and from May onward, respectively, were treated in-line with VITT recommendations (p < 0.001). Overall, treatment according to recommendations had no statistically significant influence on mortality (14/44 [32%] vs 29/55 [52%], adjusted odds ratio [OR] = 0.43, 95% confidence interval [CI] = 0.16-1.19). However, patients who received immunomodulation had lower mortality (19/65 [29%] vs 24/34 [70%], adjusted OR = 0.19, 95% CI = 0.06-0.58). Treatment with non-heparin anticoagulants instead of heparins was not associated with lower mortality (17/51 [33%] vs 13/35 [37%], adjusted OR = 0.70, 95% CI = 0.24-2.04). Mortality was also not significantly influenced by platelet transfusion (17/27 [63%] vs 26/72 [36%], adjusted OR = 2.19, 95% CI = 0.74-6.54). CONCLUSIONS: In patients with VITT-CVT, adherence to VITT treatment recommendations improved over time. Immunomodulation seems crucial for reducing mortality of VITT-CVT. ANN NEUROL 2022;92:562-573.


Assuntos
COVID-19 , Trombose Intracraniana , Trombose Venosa , Adenoviridae , Anticoagulantes/uso terapêutico , Vacinas contra COVID-19/efeitos adversos , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , SARS-CoV-2 , Vacinação/efeitos adversos , Trombose Venosa/complicações
4.
Int J Mol Sci ; 24(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37108185

RESUMO

Usually, after an abnormal level of serum prostate-specific antigen (PSA) or digital rectal exam, men undergo a prostate needle biopsy. However, the traditional sextant technique misses 15-46% of cancers. At present, there are problems regarding disease diagnosis/prognosis, especially in patients' classification, because the information to be handled is complex and challenging to process. Matrix metalloproteases (MMPs) have high expression by prostate cancer (PCa) compared with benign prostate tissues. To assess the possible contribution to the diagnosis of PCa, we evaluated the expression of several MMPs in prostate tissues before and after PCa diagnosis using machine learning, classifiers, and supervised algorithms. A retrospective study was conducted on 29 patients diagnosed with PCa with previous benign needle biopsies, 45 patients with benign prostatic hyperplasia (BHP), and 18 patients with high-grade prostatic intraepithelial neoplasia (HGPIN). An immunohistochemical study was performed on tissue samples from tumor and non-tumor areas using specific antibodies against MMP -2, 9, 11, and 13, and the tissue inhibitor of MMPs -3 (TIMP-3), and the protein expression by different cell types was analyzed to which several automatic learning techniques have been applied. Compared with BHP or HGPIN specimens, epithelial cells (ECs) and fibroblasts from benign prostate biopsies before the diagnosis of PCa showed a significantly higher expression of MMPs and TIMP-3. Machine learning techniques provide a differentiable classification between these patients, with greater than 95% accuracy, considering ECs, being slightly lower when considering fibroblasts. In addition, evolutionary changes were found in paired tissues from benign biopsy to prostatectomy specimens in the same patient. Thus, ECs from the tumor zone from prostatectomy showed higher expressions of MMPs and TIMP-3 compared to ECs of the corresponding zone from the benign biopsy. Similar differences were found for expressions of MMP-9 and TIMP-3, between fibroblasts from these zones. The classifiers have determined that patients with benign prostate biopsies before the diagnosis of PCa showed a high MMPs/TIMP-3 expression by ECs, so in the zone without future cancer development as in the zone with future tumor, compared with biopsy samples from patients with BPH or HGPIN. Expression of MMP -2, 9, 11, and 13, and TIMP-3 phenotypically define ECs associated with future tumor development. Also, the results suggest that MMPs/TIMPs expression in biopsy tissues may reflect evolutionary changes from prostate benign tissues to PCa. Thus, these findings in combination with other parameters might contribute to improving the suspicion of PCa diagnosis.


Assuntos
Hiperplasia Prostática , Neoplasia Prostática Intraepitelial , Neoplasias da Próstata , Masculino , Humanos , Inibidor Tecidual de Metaloproteinase-3 , Inteligência Artificial , Estudos Retrospectivos , Neoplasias da Próstata/metabolismo , Neoplasia Prostática Intraepitelial/patologia , Biópsia , Hiperplasia Prostática/patologia , Metaloproteases
5.
Molecules ; 28(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37175088

RESUMO

Secamone afzelii (Roem. & Schult.) K. Schum (family Asclepiadaceae) is a creeping woody climber used to treat ailments in many traditional medicine systems. The present study aims to examine the antioxidant and enzyme inhibition activities of S. afzelii leaf using different compositions of methanol-water mixture as an extraction solvent. The extracts were characterized by HPLC-ESI-MSn in terms of chemical compounds. The in silico results show that compound 23 (quercitrin) has the higher docking scores among the selected substances and the MD simulation revealed that the interactions with the enzymatic pocket are stable over the simulation time and strongly involve the tyrosinase catalytic Cu atoms. All together the results showed that both 80% and 100% methanolic extracts contained significantly (p < 0.05) the highest total phenolics content while the highest content of total flavonoids was significantly (p < 0.05) extracted by 100% methanol. About 26 compounds were tentatively identified by HPLC-ESI-MSn and 6 of them were quantified using standards. Results showed that the extracts were rich in flavonoids with a relatively high abundance of two kaempferol glycosides comprising 60% of quantified compounds. The 100% and 80% methanol extracts recorded significantly (p < 0.05) the highest total antioxidant, DPPH and ABTS activity as well as tyrosinase and ⍺-amylase inhibitory activities. The best significant (p < 0.05) cholinesterase inhibitory activity and reducing capacity of Fe+++ and Cu++ was recorded from the 80% methanolic extract while 100% ethanolic extract gave the highest significant (p < 0.05) butyrylcholinesterase inhibitory activity. The best glucosidase activity was observed in the 50% and 80% methanolic extracts. Although the water extract displayed the least total phenolics and flavonoids content and consequently the lowest antioxidant and enzyme inhibition activity, it displayed significantly (p < 0.05) the highest chelating power. In conclusion, these results demonstrated the richness of S. afzelii leaf as a potential source of bioactive compounds for the food industry, for the preparation of food supplements and functional foods.


Assuntos
Antioxidantes , Inibidores Enzimáticos , Inibidores Enzimáticos/farmacologia , Antioxidantes/química , Metanol/química , Monofenol Mono-Oxigenase , Extratos Vegetais/química , Butirilcolinesterase , Folhas de Planta/química , Flavonoides/farmacologia , Flavonoides/análise , Fenóis/análise , Indústria Alimentícia , Água/análise
6.
Gastroenterol Hepatol ; 46(6): 425-438, 2023.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36243249

RESUMO

BACKGROUND: Retrospective studies suggest that coronavirus disease (COVID-19) commonly involves gastrointestinal (GI) symptoms and complications. Our aim was to prospectively evaluate GI manifestations in patients hospitalized for COVID-19. METHODS: This international multicentre prospective cohort study recruited COVID-19 patients hospitalized at 31 centres in Spain, Mexico, Chile, and Poland, between May and September 2020. Patients were followed-up until 15 days post-discharge and completed comprehensive questionnaires assessing GI symptoms and complications. A descriptive analysis as well as a bivariate and multivariate analysis were performer using binary logistic regression. p<0.05 was considered significant. RESULTS: Eight hundred twenty-nine patients were enrolled; 129 (15.6%) had severe COVID-19, 113 (13.7%) required ICU admission, and 43 (5.2%) died. Upon admission, the most prevalent GI symptoms were anorexia (n=413; 49.8%), diarrhoea (n=327; 39.4%), nausea/vomiting (n=227; 27.4%), and abdominal pain (n=172; 20.7%), which were mild/moderate throughout the disease and resolved during follow-up. One-third of patients exhibited liver injury. Non-severe COVID-19 was associated with ≥2 GI symptoms upon admission (OR 0.679; 95% CI 0.464-0.995; p=0.046) or diarrhoea during hospitalization (OR 0.531; 95% CI 0.328-0.860; p=0.009). Multivariate analysis revealed that worse hospital outcomes were not independently associated with liver injury or GI symptoms. CONCLUSION: GI symptoms were more common than previously documented, and were mild, rapidly resolved, and not independently associated with COVID-19 severity. Liver injury was a frequent complication in hospitalized patients not independently associated with COVID-19 severity.


Assuntos
COVID-19 , Gastroenteropatias , Humanos , COVID-19/complicações , Estudos Retrospectivos , SARS-CoV-2 , Estudos Prospectivos , Assistência ao Convalescente , Alta do Paciente , Gastroenteropatias/etiologia , Gastroenteropatias/complicações , Diarreia/epidemiologia , Diarreia/etiologia
7.
Molecules ; 27(24)2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36558163

RESUMO

In this study, the methanolic and infusion extracts of two species, Thymbra capitata and Thymus sipyleus subsp. rosulans, were tested for their chemical composition and biological abilities (antioxidant, enzyme inhibitory and anti-inflammatory effects). The extracts yielded total phenolic and flavonoid contents in the range of 83.43-127.52 mg GAE/g and 9.41-46.34 mg RE/g, respectively. HPLC analysis revealed rosmarinic acid to be a major component of the studied extracts (15.85-26.43%). The best ABTS radical scavenging ability was observed in the methanol extract of T. capitata with 379.11 mg TE/g, followed by in the methanol extract of T. sipylus (360.93 mg TE/g). In the CUPRAC assay, the highest reducing ability was also found in the methanol extract of T. capitata with 802.22 mg TE/g. The phosphomolybdenum ability ranged from 2.39 to 3.61 mmol TE/g. In terms of tyrosinase inhibitory effects, the tested methanol extracts (83.18-89.66 mg KAE/g) were higher than the tested water extracts (18.74-19.11 mg KAE/g). Regarding the BChE inhibitory effects, the methanol extracts were active on the enzyme while the water extracts showed no inhibitory effect on it. Overall, the methanolic extracts showed better enzyme inhibition compared to the infusion extracts. Molecular docking also showed the selected exhibited potential binding affinities with all enzymes, with a preference for cholinesterases. Additionally, the extracts were effective in attenuating the LPS-induced increase in COX-2 and IL-6 gene expression in isolated colon, thus indicating promising anti-inflammatory effects. The preliminary results of this study suggest that these species are good natural sources of antioxidants and also provide some scope as enzyme inhibitors, most likely due to their bioactive contents such as phenolic acids, and thus can be exploited for different applications related to health promotion and disease prevention.


Assuntos
Lamiaceae , Thymus (Planta) , Simulação de Acoplamento Molecular , Metanol/química , Extratos Vegetais/química , Antioxidantes/química , Água , Anti-Inflamatórios/farmacologia
8.
J Fish Biol ; 99(3): 765-772, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33861470

RESUMO

In this study, the authors examined late atretic follicles in the ovaries of Atlantic bluefin tuna, Thunnus thynnus (Linnaeus 1758), at different times of the year using transmitted light and epifluorescence microscopy. Atresia (degeneration and resorption of developing ovarian follicles) is a natural process involved in fecundity downregulation in teleosts and is substantially enhanced in stressful conditions. Early (α and ß) atretic stages of yolked oocytes have a relatively short duration in seasonally reproducing species, whereas later (γ and δ) atretic follicles (LAF) persist for longer time in the ovary, serving as a sign of previous vitellogenic activity. LAF can thus be used as reliable markers of maturity during non-reproductive periods. Lipofuscin granules accumulate in the cytoplasm of LAF cells as a result of lysosomal digestion of oocyte components. Taking advantage of the well-known autofluorescent properties of lipofuscins, LAF may be identified in unstained histological sections under fluorescence microscopy using appropriate excitation and emission wavelengths. The authors explore in this study the applicability of fluorescence microscopy to provide a fast and effective method to assess late atresia in fishes. This method may be particularly useful to determine sexual maturity in individuals sampled long after the spawning season, where LAF are difficult to detect in standard histological sections. Furthermore, LAF autofluorescence provides a rapid way to quantify late atresia in fishes using image analysis.


Assuntos
Atresia Folicular , Ovário , Animais , Feminino , Peixes , Folículo Ovariano , Atum
9.
J Fish Biol ; 97(2): 409-415, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32402108

RESUMO

This study provides sound evidence of the spawning activity of common dolphinfish (Coryphaena hippurus) in the Gulf of Cadiz (southwest Spain) during summer months. Along with waters off Côte d'Ivoire, this area adjacent to the Mediterranean Sea is the easternmost Atlantic spawning ground documented for the species. All the fish analysed (5 males and 15 females) were at spawning stage, except the smallest female (61.5 cm in fork length), which might not have yet reached sexual maturation. The oceanographic conditions during the samplings were similar to those occurring during the peak spawning season in the Gulf of Mexico. The study results are consistent with recent genetic studies indicating differentiation between Mediterranean and Atlantic dolphinfish populations, with the Strait of Gibraltar representing a boundary between two distinct reproductive units. The present results may contribute to improve the understanding of the dynamics of dolphinfish population and the management of eastern Atlantic and Mediterranean stocks.


Assuntos
Perciformes/fisiologia , Reprodução , Comportamento Sexual Animal/fisiologia , Animais , Oceano Atlântico , Feminino , Masculino , Mar Mediterrâneo , Estações do Ano , Espanha
12.
Mikrochim Acta ; 186(12): 781, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729601

RESUMO

Two methods for the luminescence determination of cysteine (Cys) are presented. They make use of either silver nanoparticles (Ag NPs) or graphene quantum dots (GQDs), both doped with terbium(III). The methods are based on the finding that Cys quenches the green luminescence of Tb(III)-Ag NPs and Tb(III)-GQDs. The excitation/emission maxima are at 306/545 and 257/545 nm, for both nanoprobes, respectively. Response is linear in the 0.28-5.0 µg mL-1 Cys concentration range for the Tb(III)-Ag NP system, and from 0.05-3.0 µg mL-1 for the Tb(III)-GQD system. The respective limits of detection are 0.09 and 0.015 µg mL-1. The probes were applied to the time-resolved luminometric determination of Cys in (spiked) food supplements and gave satisfactory results. Graphical abstractSchematic representation of the quenching by cysteine (Cys) of the time-resolved luminescence (TSL) of terbium-graphene quantum dots [Tb(III)-GQD] and of terbium-silver nanoparticles [Tb(III)-Ag NP].

13.
Molecules ; 24(22)2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31744256

RESUMO

: Berberis species are known for their use in traditional medicine. Here, we report the phenolic composition and bioactivity of methanolic and aqueous extracts of Berberis thunbergii DC. leaves. The phenolic profiling and the quantitation of the main compounds were performed by high-performance liquid chromatography with diode array and mass spectrometry detections. The most abundant compounds in both extracts were caffeoylquinic acids (chlorogenic acid, particularly, with a concentration of 90.1-101.3 mg g-1 dried extract), followed by caffeoylglucaric acids and quercetin glycosides. Antioxidant and radical scavenging assays (phosphomolybdenum, DPPH, ABTS, CUPRAC, FRAP, metal chelating activity), as well as enzyme inhibitory assays (acetylcholinesterase, butyrylcholinesterase, tyrosinase, amylase, glucosidase, and lipase), were carried out to evaluate the potential bioactivity of B. thunbergii. The methanolic extract presented the highest antioxidant and radical scavenging values, in agreement with its higher phenolic content. Regarding enzyme inhibitory potential, the methanolic extract was also more potent than the aqueous one. Hence, B. thunbergii leaves represent a suitable candidate for the preparation of pharmaceutical or nutraceutical products.


Assuntos
Antioxidantes/farmacologia , Berberis/química , Inibidores Enzimáticos/farmacologia , Fenóis/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/química , Flavonoides/química , Hidroxibenzoatos/química , Espectrometria de Massas , Extratos Vegetais/química
14.
Anal Bioanal Chem ; 410(2): 391-398, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29147748

RESUMO

We propose an alternative approach for the development of analytical methods based on terbium-sensitized luminescence (TSL). TSL is based on the complexation between Tb(III) ions and fluorescent organic compounds that have appropriate functional groups to complex with Tb(III). We report the use of graphene quantum dot (GQDs) nanoparticles to improve the sensitivity and selectivity of TSL detection. GQDs can react with terbium ions through the carboxylic groups present in their structure. These Tb(III)-GQD complexes, formed in situ in aqueous solution, can be used as time-resolved luminescent probes. Ascorbic acid was selected as a target analyte to demonstrate the suitability of the proposed method. The selectivity of the TSL method was highly improved for most of the interferences tested. Under the optimum conditions [Tb(III) concentration 5 × 10-4 mol L-1, GQD concentration 4 mg L-1], a minimum 100% increase in selectivity was observed for several vitamins and common cations that may be present in the samples to be analyzed. In addition, the analytical signal showed a 30% enhancement with the use of GQDs compared with the use of merely Tb(III) ions, with a detection limit of 0.12 µg mL-1. The repeatability and intermediate precision were lower than 3% and 5%, respectively. From the results obtained, the implementation of GQDs in TSL can lead to the development of novel time-resolved luminescent probes with high analytical potential. Graphical abstract Quenching of Tb(III)-graphene quantum dot (GQD) luminescence by ascorbic acid (AA). TBL terbium-sensitized luminescence.

15.
Int Ophthalmol ; 38(2): 577-583, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28283925

RESUMO

PURPOSE: To confirm the prediction of emmetropization feedback theory that myopia can be prevented by correcting the hyperopia of a child at risk of becoming myopic. METHODS: We conducted such myopia prevention treatment with twins at risk. Their hyperopia was partially corrected by one half at age 7 and in subsequent years until age 16. RESULTS: Hyperopia progressively decreased in all eyes as expected. None of the twins developed myopia. The spherical equivalent refractions of the followed eyes were +1 and +1.25 D at age 16. Feedback theory accurately predicted these values. CONCLUSIONS: The treatment of the twins with partial correction of their hyperopia was successful. Prevention of myopia with this technique is relatively simple and powerful. The use of this myopia prevention treatment has no adverse effects. This prevention treatment is indicated in children with a hyperopic reserve at risk of developing myopia.


Assuntos
Atropina/uso terapêutico , Hiperopia/tratamento farmacológico , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Midriáticos/uso terapêutico , Miopia/prevenção & controle , Criança , Feminino , Humanos , Hiperopia/fisiopatologia , Masculino , Refração Ocular/fisiologia , Gêmeos
17.
Optik (Stuttg) ; 127(2): 896-899, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26709316

RESUMO

Experimental design phase of a pilot study at Annapolis is described, using reading glasses, +1.5 D. to +3.0 D. to alleviate college myopia. College students often become 1.0 to 2.0 diopters more myopic, so reading glasses were explored to partially cancel the effects of the study environment. N = 25 different sets of (+)Add lenses are evaluated, for required adjustment period and reading comfort. Three computer models are developed to predict refraction versus time. Basic control system equations predict exponential myopia shift of refractive state R(t) with time constant t0 = 100 days. Linear, exponential and Gompertz computer results are compared calculating refraction R(t) during the college years, showing correlation coefficients |r| = 0.96 to 0.97, accurate +/-0.31 D. over a 14 year interval. Typical college myopia rate is -0.3 to -0.4 D/yr. Reading glasses may be a simple, practical solution to stabilize college myopia.

18.
Int Ophthalmol ; 36(5): 609-14, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26757932

RESUMO

The objective herein is to provide refraction data, myopia progression rate, prevalence, and 1st and 2nd generation correlations, relevant to whether myopia is random or inherited. First- and second-generation ocular refraction data are assembled from N = 34 families, average of 2.8 children per family. From this group, data are available from N = 165 subjects. Inter-generation regressions are performed on all the data sets, including correlation coefficient r, and myopia prevalence [%]. Prevalence of myopia is [M] = 38.5 %. Prevalence of high myopes with |R| >6 D is [M-] = 20.5 %. Average refraction is  = -1.84 D ± 3.22 (N = 165). For the high myopes, |R| >6 D, prevalence for the parents is [M-] = 25 %, for the 2nd generation [M-] = 16.5 %. Average myopia level for the high myopes, both generations, is  = -7.52 D ± 1.31 D (N = 33). Regression parameters are calculated for all the data sets, yielding correlation coefficients in the range r = 0.48-0.72 for some groups of myopes and high myopes, fathers to daughters, and mothers to sons. Also of interest, some categories show essentially no correlation, -0.20 < r < 0.20, indicating that the refractive errors occur randomly. Time series results show myopia diopter rates = -0.50 D/year.


Assuntos
Filho de Pais com Deficiência/estatística & dados numéricos , Miopia , Refração Ocular/fisiologia , Adulto , Progressão da Doença , Família , Pai , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Mães , Prevalência
19.
Anal Bioanal Chem ; 407(2): 521-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25370162

RESUMO

A new approach for the implementation of liquid-liquid extraction in a sequential injection manifold is presented. The manifold consists of two syringe pumps and one multi-position valve. The use of a 30 % MeOH/H2O (v/v) solution as the carrier, with isobutanol as the extractant, made it possible to avoid the problems associated with the different affinities of the organic and aqueous phases for Teflon tubing, and the formation of bubbles. The suitability of the proposed method was demonstrated by the determination of thiamine in pharmaceutical preparations and dietary supplements. Detection and quantification limits were estimated as 9 and 30 µg L(-1), respectively. The repeatability was lower than 3 % and the intermediate precision (3 d) was lower than 7 %. The sample throughput was 14 samples per h. The results were in agreement with a high-performance liquid chromatography-electrospray/mass spectrometry reference method.

20.
Graefes Arch Clin Exp Ophthalmol ; 253(8): 1273-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25863670

RESUMO

PURPOSE: This study seeks to demonstrate the existence of a feedback loop controlling myopia by comparing the prediction of a feedback model to the actual progression of corrected myopia. In addition to theoretical results, confirming clinical data are presented. METHODS: The refraction of 13 continuously corrected myopic eyes was collected over a period of time ranging from 4 to 9 years from the time of their first correction. Refractive data was collected in an optometry office from myopic young subjects from the general population in Boston. Subjects were myopes, ages 2 to 22 at the time of first correction selected randomly from a larger population. All individuals were fully corrected with lenses; new lenses were prescribed every time that their myopia increased by 0.25 diopters or more. Subjects wore their spectacle lenses during the followed period. RESULTS: Subjects exhibit a linear time course of myopia progression when corrected with lenses. The observed rate of myopia increase is 0.2 to 1.0 diopters/year, with a mean correlation coefficient r = -0.971, p < 0.005. CONCLUSIONS: This report establishes that feedback control theory applies to the clinical phenomenon of progressive myopia. Continuous correction of myopia results in a linear progression that increases myopia. The Laplace transformation of temporal refractive data to the s-domain simplifies the study of myopia and emmetropia. The feedback transfer function predicts that continuous correction of myopia results in a linear progression because continuous correction opens the feedback loop. This prediction is confirmed with all subjects.


Assuntos
Óculos , Miopia/diagnóstico , Miopia/terapia , Adolescente , Adulto , Criança , Pré-Escolar , Progressão da Doença , Humanos , Refração Ocular/fisiologia
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