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1.
Arq. bras. oftalmol ; 87(4): e2022, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1520232

RESUMO

ABSTRACT Purpose: To compare the differences between the apparent and actual chord μ. Methods: In this prospective, comparative, non-randomized, and non-interventional study, imaging examinations using Pentacam and the HD Analyzer were performed in the same room under the same scotopic conditions. The inclusion criteria were patients aged 21-71 years, able to provide informed consent, myopia up to 4D, and anterior topographic astigmatism up to 1D. Patients using contact lenses, those with previous eye diseases or surgeries, corneal opacities, corneal tomographic changes, or suspected keratoconus were excluded. Results: Altogether, 116 eyes of 58 patients were analyzed. The patients' mean age was 30.69 (±7.85) years. In the correlation analyses, Pearson's correlation coefficient of 0.647 indicates a moderate positive linear relationship between apparent and actual chord μ. The mean actual and apparent chord μ were 226.21 ± 128.53 and 278.66 ± 123.90 μm, respectively, with a mean difference of 52.45 μm (p=0.01). The analysis of mean pupillary diameter resulted in 5.76 mm using the HD Analyzer and 3.31 mm using the Pentacam. Conclusions: We found a correlation between the two measurement devices, and even though we found considerable differences, both can be used in daily practice. Given their differences, we should respect their peculiarities as well.


RESUMO Objetivo: Comparar as diferenças entre a chord aparente μ e o chord real μ. Métodos: Estudo prospectivo, comparativo, não randomizado e não intervencionista. Os exames de imagem (Pentacam e HD Analyzer) foram realizados na mesma sala e nas mesmas condições escotópicas. Os critérios de inclusão foram idade de 21 a 71 anos; compreensão do termo de consentimento; miopia até 4D e astigmatismo topográfico anterior até 1D. Os critérios de exclusão foram usuários de lentes de contato; pacientes com doenças oculares prévias ou cirurgias; opacidades da córnea; a presença de alterações tomográficas da córnea ou suspeita de ceratocone. Resultados: Em nosso estudo foram analisados 116 olhos de 58 pacientes. A média de idade foi de 30,69 anos (± 7,85). Análises de correlação foram desenvolvidas e o coeficiente de correlação de Pearson (0,647) indica uma relação linear positiva moderada entre as variáveis. A média do chord μ real foi 226,21 ± 128,53 μm e a média do chord μ média foi 278,66 ± 123,90 μm, com diferença média de 52,45 μm (p=0,01). A análise do diâmetro pupilar médio apresentou: 5,76mm no HD Analyzer e 3,31mm no Pentacam. Conclusões: Entendemos a existência de uma diferença significativa entre os métodos e assim a medida de ambos os dispositivos com base em princípios diferentes devemos respeitar suas peculiaridades. Como encontramos correlação entre as duas medidas, acreditamos que ambas podem ser utilizadas na prática diária.

2.
Arq Bras Oftalmol ; 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36995814

RESUMO

PURPOSE: To compare the differences between the apparent and actual chord µ. METHODS: In this prospective, comparative, non-randomized, and non-interventional study, imaging examinations using Pentacam and the HD Analyzer were performed in the same room under the same scotopic conditions. The inclusion criteria were patients aged 21-71 years, able to provide informed consent, myopia up to 4D, and anterior topographic astigmatism up to 1D. Patients using contact lenses, those with previous eye diseases or surgeries, corneal opacities, corneal tomographic changes, or suspected keratoconus were excluded. RESULTS: Altogether, 116 eyes of 58 patients were analyzed. The patients' mean age was 30.69 (±7.85) years. In the correlation analyses, Pearson's correlation coefficient of 0.647 indicates a moderate positive linear relationship between apparent and actual chord µ. The mean actual and apparent chord µ were 226.21 ± 128.53 and 278.66 ± 123.90 µm, respectively, with a mean difference of 52.45 µm (p=0.01). The analysis of mean pupillary diameter resulted in 5.76 mm using the HD Analyzer and 3.31 mm using the Pentacam. CONCLUSIONS: We found a correlation between the two measurement devices, and even though we found considerable differences, both can be used in daily practice. Given their differences, we should respect their peculiarities as well.

3.
Plants (Basel) ; 11(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36432875

RESUMO

Inhibition of systemic inflammation has been a beneficial strategy in treating several non-communicable diseases, which represent one of the major causes of mortality in the world. The Peroxisome Proliferator-Activated Receptors (PPAR) are interesting pharmacological targets, since they can act both through the metabolic and anti-inflammatory pathways. Morus nigra L. has flavonoids in its chemical composition with recognized anti-oxidant activity and often associated with anti-inflammatory activity. Therefore, this study aimed to evaluate the hydroethanolic extract of M. nigra leaves' ability to activate PPAR and promote anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated murine macrophage cells. The leaf extract was prepared by cold maceration, and the chemical profile was obtained by HPLC-DAD. Activation of PPAR α and γ was evaluated by the luciferase reporter assay. The anti-inflammatory activity was assessed by measuring the reactive oxygen species (ROS), nitric oxide (NO), and Tumor Necrosis Factor-α (TNF-α) in RAW 264.7 cells after stimulation with LPS from Escherichia coli. The HPLC-DAD analysis identified two major compounds: rutin and isoquercitrin. The extract showed agonist activity for the two types of PPAR, α and γ, although its major compounds, rutin and isoquercitrin, did not significantly activate the receptors. In addition, the extract significantly reduced the production of ROS, NO, and TNF-α. Treatment with the specific PPAR-α antagonist, GW 6471, was able to partially block the anti-inflammatory effect caused by the extract.

4.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35745665

RESUMO

L-asparaginase is an important enzyme in the pharmaceutical field used as treatment for acute lymphoblastic leukemia due to its ability to hydrolyze L-asparagine, an essential amino acid synthesized by normal cells, but not by neoplastic cells. Adverse effects of L-asparaginase formulations are associated with its glutaminase activity and bacterial origin; therefore, it is important to find new sources of L-asparaginase produced by eukaryotic microorganisms with low glutaminase activity. This work aimed to identify the L-asparaginase gene sequence from Penicillium sizovae, a filamentous fungus isolated from the Brazilian Savanna (Cerrado) soil with low glutaminase activity, and to biosynthesize higher yields of this enzyme in the yeast Komagataella phaffii. The L-asparaginase gene sequence of P. sizovae was identified by homology to L-asparaginases from species of Penicillium of the section Citrina: P. citrinum and P. steckii. Partial L-asparaginase from P. sizovae, lacking the periplasmic signaling sequence, was cloned, and expressed intracellularly with highest enzymatic activity achieved by a MUT+ clone cultured in BMM expression medium; a value 5-fold greater than that obtained by native L-asparaginase in P. sizovae cells. To the best of our knowledge, this is the first literature report of the heterologous production of an L-asparaginase from a filamentous fungus by a yeast.

5.
Eur J Ophthalmol ; 32(5): 3103-3109, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35348412

RESUMO

PURPOSE: Report a new technique for improvement of pterygium surgery: donor graft harvesting with air. CASE REPORTS: We describe a technique that was used with 138 patients who underwent surgery that included a conjunctival autograft and fibrin glue with air injection to dissect the Tenon capsule from the conjunctiva. RESULTS: No complications occurred with this technique and all patients achieved good results. DISCUSSION: The surgical time with this new technique was similar to that reported in the literature. In addition, the graft thickness was close to that reported with femtosecond laser dissection and it was thinner than that reported with aesthetic/saline dissection (unable to determine statistical significance). CONCLUSIONS AND IMPORTANCE: With the injection of an air bubble, we could easily dissect the conjunctiva from the Tenon capsule and quickly acquire thin grafts without any additional costs or complications.


Assuntos
Pterígio , Adesivos Teciduais , Túnica Conjuntiva/transplante , Adesivo Tecidual de Fibrina/uso terapêutico , Seguimentos , Humanos , Complicações Pós-Operatórias , Pterígio/cirurgia , Transplante Autólogo
6.
Sci Rep ; 11(1): 17861, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504186

RESUMO

The enzyme L-asparaginase (L-ASNase) is used in the treatment of Acute Lymphoblastic Leukemia. The preparations of this enzyme for clinical use are derived from bacterial sources and its use is associated with serious adverse reactions. In this context, it is important to find new sources of L-ASNase. In this work, the Placket-Burman Experimental Design (PBD) was used to determine the influence of the variables on the L-ASNase production then it was followed by a 28-4 Factorial Fractional Design (FFD). The results obtained from PBD have shown a range of L-ASNase activity, from 0.47 to 1.77 U/gcell and the results obtained from FFD have showed a range of L-ASNase activity, from 1.10 to 2.36 U/gcell. L-proline and ammonium sulfate were identified as of significant positive variables on this production enzyme by Penicillium cerradense sp. nov. The precise identification of this new species was confirmed by morphological characteristics and sequence comparisons of the nuclear 18S-5.8S-28S partial nrDNA including the ITS1 and ITS2 regions, RNA polymerase II, ß-tubulin and calmodulin genomic regions. The genetic sequence coding for the L-ASNase was obtained after carrying out a full genome sequencing. The L-ASNase expressed by P. cerradense sp. nov may have promising antineoplastic properties.


Assuntos
Antineoplásicos/uso terapêutico , Asparaginase/genética , Penicillium/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Prolina/genética , Asparaginase/uso terapêutico , Humanos , Penicillium/metabolismo , Prolina/uso terapêutico , Análise de Sequência de DNA/métodos
7.
Pharmaceutics ; 13(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34452229

RESUMO

l-asparaginase is an enzyme used as treatment for acute lymphoblastic leukemia (ALL) due to its ability to hydrolyze l-asparagine, an essential amino acid synthesized by normal cells unlike neoplastic cells. The adverse effects of l-asparaginase formulations are associated with its glutaminase activity and bacterial origin; therefore, it is important to find new sources of l-asparaginase-producing eukaryotic microorganisms with low glutaminase activity. This work evaluated the biotechnological potential of filamentous fungi isolated from Brazilian Savanna soil and plants for l-asparaginase production. Thirty-nine isolates were screened for enzyme production using the plate assay, followed by measuring enzymatic activity in cells after submerged fermentation. The variables influencing l-asparaginase production were evaluated using Plackett-Burman design. Cell disruption methods were evaluated for l-asparaginase release. Penicillium sizovae 2DSST1 and Fusarium proliferatum DCFS10 showed the highest l-asparaginase activity levels and the lowest glutaminase activity levels. Penicillium sizovae l-asparaginase was repressed by carbon sources, whereas higher carbon concentrations enhanced l-asparaginase by F. proliferatum. Maximum enzyme productivity, specific enzyme yield and the biomass conversion factor in the enzyme increased after Plackett-Burman design. Freeze-grinding released 5-fold more l-asparaginase from cells than sonication. This study shows two species, which have not yet been reported, as sources of l-asparaginase with possible reduced immunogenicity for ALL therapy.

8.
Bol. latinoam. Caribe plantas med. aromát ; 20(4): 427-442, jul. 2021. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1369497

RESUMO

The objective of this study was to evaluate biological and phytochemical properties of the aqueous extract from the leaves of Miconia chamissois Naudin (AEMC). Phytochemical properties were assessed by analyzing the chromatographic profile and the polyphenol content of AEMC. Biological properties evaluation was conducted based on cytotoxicity assay and by evaluating the antioxidant, antimicrobial, and enzymatic inhibition activities. Results indicated the presence of phytochemicals in AEMC such as flavonoids and polyphenols, including rutin, isoquercitrin and vitexin derivatives. AEMC showed antioxidant activity, which may be attributed to the high polyphenolic content. Moreover, AEMC demonstrated in vitro enzyme inhibition activity against tyrosinase and alpha-amylase, as well as showed low cytotoxicity. On the other hand, AEMC exhibited weak antimicrobial activity against S. aureusand C. albicans. Thus, AEMC is a promising alternative in search of potential drugs for the treatment of diseases induced by oxidative stress and inflammation, conditions due to hyperpigmentation processes, such as melisma, as well as for diabetes.


El objetivo de este estudio fue detectar las propiedades biológicas y fitoquímicos del extracto acuoso de las hojas de Miconia chamissois Naudin (AEMC). Las propiedades fitoquímicas se evaluaron analizando el perfil cromatográfico y el contenido de polifenoles de AEMC. La evaluación de las propiedades biológicas se realizó en base al ensayo de citotoxicidad y evaluando las actividades de inhibición antioxidante, antimicrobiana y enzimática. Los resultados indicaron la presencia de fitoquímicos en AEMC, como flavonoides y polifenoles, que incluyen derivados de rutina, isoquercitrina y vitexina. AEMC mostró una actividad antioxidante considerable, que puede atribuirse al alto contenido polifenólico. Además, AEMC exhibió actividad de inhibición enzimática in vitro contra tirosinasa y alfa-amilasa, así como mostró baja citotoxicidad. Por otro lado, AEMC demostró actividad antimicrobiana débil contra S. aureusy C. albicans. Por lo tanto, AEMC es una alternativa prometedora en busca de posibles drogas para el tratamiento de enfermedades inducidas por el estrés oxidativo y la inflamación, afecciones debidas a procesos de hiperpigmentación, como el melasma, así como para la diabetes.


Assuntos
Extratos Vegetais/farmacologia , Extratos Vegetais/química , Melastomataceae/química , Flavonoides/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Monofenol Mono-Oxigenase/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores , Polifenóis/análise , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia
9.
Eur J Ophthalmol ; 31(6): 3505-3510, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34058904

RESUMO

OBJECTIVE: Evaluation of central corneal densitometry changes following Ferrara corneal ring segment implantation in patients with keratoconus, especially the correlation between corneal densitometry and keratometry. METHODS: Retrospective, non-comparative, interventional study based on the review of medical records of patients diagnosed with keratoconus who underwent Ferrara corneal ring segment implantation. Pre and post-operative corneal densitometry measurements obtained with Pentacam HR (Oculus, Wetzlar, Germany) were analyzed. The follow-up time was 3 months, and data comparison was made, using specific statistical analysis, with the data of 3 months postoperatively. RESULTS: The study sample consisted of 43 eyes of 36 patients. The mean corrected visual acuity improved from 0.82 LogMAR preoperatively (SD ± 0.33) to 0.19 LogMAR (SD ± 0.13) postoperatively. The mean spherical equivalent varied from -4.63 (SD ± 3.94) preoperatively to -2.16 (SD ± 2.63) postoperatively. Asphericity varied from -0.69 (SD ± 0.32) preoperatively to -0.27 (SD ± 0.31) postoperatively. The mean maximum K was 54.01D (SD ± 3.38) preoperatively and 51.50D (SD ± 2.90) postoperatively. The mean anterior densitometric value was 18.26 (SD ± 2.03) preoperatively and 17.66 (SD ± 1.84) postoperatively. CONCLUSION: Corneal densitometry is an interesting technology that should be studied in keratoconus patients. Our results suggest that the corneal densitometry in the cornea's anterior layer reduces after ICRS implantation and correlates with corneal keratometry. Further studies should be performed to increase the knowledge in this field.


Assuntos
Ceratocone , Córnea/diagnóstico por imagem , Substância Própria/diagnóstico por imagem , Substância Própria/cirurgia , Topografia da Córnea , Densitometria , Humanos , Ceratocone/cirurgia , Próteses e Implantes , Implantação de Prótese , Refração Ocular , Estudos Retrospectivos , Acuidade Visual
10.
Eur J Ophthalmol ; 31(6): 3483-3489, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33719637

RESUMO

OBJECTIVE: To investigate the role of ICRS in halting keratoconus progression in a large sample of patients. METHODS: A retrospective, non-comparative, interventional study based on the review of medical records of patients diagnosed with keratoconus who underwent Ferrara corneal ring segment implantation. A retrospective chart analysis study of 123 operated eyes with follow-up ranging from 3 to 16 years (mean 5.3 ± 3.6 years) was performed. This study was carried out at Ocular Surgery Unit, São Paulo, Brazil. All topographic data were obtained from Pentacam (Oculus, Arlington, USA). The same surgeon performed all surgeries, and the Ferrara ICRS nomogram was used for ICRS selection in all cases. RESULTS: Corrected distance visual acuity, keratometry, and topographic astigmatism improved in most cases, with statistical significance. In 42 eyes (53.8%), there was an increase in K1 or K2, and in 36 (46.2%), there was a reduction or maintenance in K1. Considering a difference higher than 1 D, between 3-month post-surgery and final visit (group 3), 32 eyes (41%) showed an increase, and 46 eyes (59%) ended equal or below this value. CONCLUSION: The implantation of ICRS showed improvement in visual and keratometric indexes. The majority of patients did not increase more than one diopter in keratometric values after ICRS implantation. ICRS may be effective for slowing disease progression, especially in older patients.


Assuntos
Ceratocone , Idoso , Brasil , Substância Própria/cirurgia , Topografia da Córnea , Humanos , Ceratocone/cirurgia , Próteses e Implantes , Implantação de Prótese , Refração Ocular , Estudos Retrospectivos
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