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1.
Antibodies (Basel) ; 13(1)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38534210

RESUMO

Gallbladder cancer (GBC) is a very aggressive malignant neoplasm of the biliary tract with a poor prognosis. There are no specific therapies for the treatment of GBC or early diagnosis tools; for this reason, the development of strategies and technologies that facilitate or allow an early diagnosis of GBC continues to be decisive. Phage display is a robust technique used for the production of monoclonal antibodies (mAbs) involving (1) the generation of gene libraries, (2) the screening and selection of isoforms related to an immobilized antigen, and (3) the in vitro maturation of the affinity of the antibody for the antigen. This research aimed to construct a human immune library from PBMCs of GBC patients and the isolation of scFv-phage clones with specificity against the larger extracellular loop belonging to claudin 18.2, which is an important biomarker overexpressed in GBC as well as gastric cancer. The immune-library-denominated GALLBLA1 was constructed from seven GBC patients and has a diversity of 6.12 × 1010pfu mL-1. After three rounds of panning, we were able to identify clones with specificity against claudin 18.2. GALLBLA1 can contribute to the selection, isolation, and recombinant production of new human mAbs candidates for the treatment of gastrointestinal cancers.

2.
Injury ; 54 Suppl 6: 110806, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38143131

RESUMO

Type I Young and Burgess anterior posterior compression (APC) pelvic injuries have been classically managed non operatively due to theoretical integrity of sacroiliac joint ligaments (SIJL), though examination under anesthesia (EUA) has been proven occult mechanical instability in up to 50% of these injuries.  We sought to determine the diagnostic accuracy of magnetic resonance (MRI) for detection of occult instability on APC-I injuries when compared to EUA. METHODS: Diagnostic test study of prospectively recruited patients admitted with APC-I pelvic injuries between 2015 and 2022. All patients consented to participate in this study were subjected to MRI and EUA. The evaluators of each of these tests were blinded.  On MRI evaluation, SIJL were considered compromised when unilateral injury to anterior SIJL was visualized in three or more consecutive images or in bilateral injuries, when injury to the anterior SIJL in two or more consecutive images on each side was observed. Positive EUA was considered a symphyseal diastasis over 25 mm on stress fluoroscopy. Demographic data was collected as recruited and sensitivity, specificity, accuracy, and positive and negative predictive values were calculated. Confidence interval was set at 95%. EUA was considered the gold standard in statistical analysis. RESULTS: A total of 32 patients mean aged 36 (24-61) years were included. Mean symphyseal diastasis at admission was 17.58 (11 - 25) mm. The median time from injury to EUA was 5 (0-21) days. Positive EUA was observed on 20 patients and 25 patients  presented compromised SIJL. MRI presented a sensitivity of 95% (75.13% - 99.87%), specificity of 50% (21.09% - 78.91%), positive-predictive value of 73% (60.61% to 82.93%), negative-predictive value of 87% (48.66% - 98.08%). CONCLUSION: Injury to SIJL on MRI presented an accuracy of 77% (58.29% - 89.64%) for the detection of occult pelvic instability on EUA.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Humanos , Adulto , Pelve , Articulação Sacroilíaca/diagnóstico por imagem , Articulação Sacroilíaca/cirurgia , Ligamentos Articulares , Valor Preditivo dos Testes , Imageamento por Ressonância Magnética/métodos , Ossos Pélvicos/lesões , Fraturas Ósseas/cirurgia
3.
MethodsX ; 11: 102287, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37519947

RESUMO

A methodology is proposed to achieve an effective quantification of the element Calcium in soil samples, using a portable X-ray Fluorescence (pXRF) equipment. The protocol began by preparing two ideal matrices using an increasing mass, measured on an analytical balance, of Calcium and Sodium Nitrate as binder. It is the Gravimetric technique. In both samples the fluorescent emission line of the element Calcium was calibrated using an standard reference material 1400 boneash. The validation of ideal samples of the element Calcium using the XRF technique with respect to AAS as an experimental standard, using linear correlation methods, to estimate from statistical inference the real concentration of the analyte, allowed us to appreciate that both approaches remain above the standard curve provided by AAS, with a value of 1.8 and 1.68, respectively. Which means that the tendency to evaluate Calcium samples by XRF are overestimated with respect to the curve provided by AAS. Since the last correlation coefficient is very close to 1.0 and its statistical inference equation is precisely known, the authors of this work propose to apply quantification protocol to real sediment samples.•A methodology is proposed to achieve an effective quantification of the element Calcium in soil samples, using a portable X-ray Fluorescence (pXRF) equipment•The validation of ideal samples of the element Calcium using the XRF technique with respect to AAS as an experimental standard, using linear correlation methods•This work pretend to resolve another weakness by the portable system and is that the number of accounts provided by conventional XRF are not consistent with a% w/w of analyte.

4.
Biomedicines ; 11(7)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37509725

RESUMO

Cancer is one of the leading global causes of death and disease, and treatment options are constantly evolving. In this sense, the use of monoclonal antibodies (mAbs) in immunotherapy has been considered a fundamental aspect of modern cancer therapy. In order to avoid collateral damage, it is indispensable to identify specific molecular targets or biomarkers of therapy and/or diagnosis (theragnostic) when designing an appropriate immunotherapeutic regimen for any type of cancer. Furthermore, it is important to understand the currently employed mAbs in immunotherapy and their mechanisms of action in combating cancer. To achieve this, a comprehensive understanding of the biology of cancer cell antigens, domains, and functions is necessary, including both those presently utilized and those emerging as potential targets for the design of new mAbs in cancer treatment. This review aims to provide a description of the therapeutic targets utilized in cancer immunotherapy over the past 5 years, as well as emerging targets that hold promise as potential therapeutic options in the application of mAbs for immunotherapy. Additionally, the review explores the mechanisms of actin of the currently employed mAbs in immunotherapy.

5.
Methods Mol Biol ; 2672: 225-231, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37335479

RESUMO

Silver nitrate staining to evidence the location of nucleolar organizer regions (Ag-NORs) in chromosomes is widely used as a classical method in plant cytogenetics. Here, we present the most used procedures and highlight some aspects in terms of their replicability by plant cytogeneticists. Some technical features described are materials and methods used, procedures, protocol modifications, and precautions in order to obtain positive signals. The methods to obtain Ag-NOR signals have different degrees of replicability, but do not require any sophisticated technology or equipment for their application.


Assuntos
Cromossomos de Plantas , Região Organizadora do Nucléolo , Região Organizadora do Nucléolo/genética , Coloração pela Prata , Cromossomos de Plantas/genética , Coloração e Rotulagem , Cromossomos , Citogenética , Nitrato de Prata
6.
Int. j. morphol ; 41(2)abr. 2023. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1440317

RESUMO

SUMMARY: Echinococcus granulosus (E. granulosus), is a tapeworm that spreads between intermediate and definitive hosts through the ingestion of fecal matter contaminated with the parasite's eggs. The life cycle consists of differentiation from eggs to oncospheres to embryos, which eventually form cysts in organs like the liver, lungs and others. Within these cysts are protoscolices, an intermediate stage of the parasite which develop into adult tapeworms once they infect their definitive hosts. When these hydatid cysts form in humans, it is known as Cystic Echinococcosis (CE). This disease is treated through surgical excision of the cysts and or chemotherapy with benzimidazole compounds. Understanding the morphology of the intermediate developmental stage of E. granulosus, protoscolex stage, can allow researchers to identify defining structural changes and protein functions that could be used to develop treatment modalities for CE. Unique characteristics in the tegumental surface during the protoescolex stage and proteins associated with cyst fertility have all been identified in previous research studies and bring researchers closer to understanding the underlying mechanisms of E. granulosus development, and consequently, means to disrupt it to achieve better control of the disease.


El Echinococcus granulosus (E. granulosus), es un cestodo que se propaga entre huéspedes intermedios y definitivos a través de la ingestión de materia fecal contaminada con los huevos del parásito. El ciclo de vida consiste en la diferenciación de huevos a oncosferas y embriones, que finalmente forman quistes en órganos como el hígado, los pulmones y otros. Dentro de estos quistes hay protoescólices, una etapa intermedia del parásito que se convierte en su forma adulta (tenia), una vez que infectan a sus huéspedes definitivos. Cuando estos quistes hidatídicos se desarrollan en seres humanos, se les conoce como equinococosis quística (EC). Esta enfermedad se trata mediante la extirpación quirúrgica de los quistes o la quimioterapia con compuestos benzimidazólicos. La comprensión de la morfología de la etapa de desarrollo intermedia del E. granulosus y la etapa de protosclex, puede permitir a los investigadores identificar cambios estructurales definidos y funciones de proteínas que podrían usarse para desarrollar modalidades de tratamiento para la CE. Las características únicas en la superficie tegumentaria durante la etapa de protoescolex y las proteínas asociadas con la fertilidad del quiste se han identificado en estudios de investigación anteriores y acercan a los investigadores a la comprensión de los mecanismos subyacentes del desarrollo del E. granulosus y, en consecuencia, los medios para interrumpirlo para lograr un mejor control de la enfermedad.


Assuntos
Animais , Echinococcus granulosus/anatomia & histologia , Echinococcus granulosus/crescimento & desenvolvimento , Echinococcus granulosus/patogenicidade , Equinococose
7.
Heliyon ; 9(1): e12749, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685435

RESUMO

Free-floating bike-sharing systems can have a positive influence on the mobility of urban centers and developing efficient localization strategies is crucial to avoid crowding at peak times and increase service availability. Our study aims to efficiently resolve the location of virtual bike stations in a Latin American city through a geospatial data wrangling methodology that allows us to respond opportunely to the potential demand forecasted for the city. This approach is implemented in Python, and it uses the Geopandas and LocalSolver libraries to determine locations for the virtual bike stations that maximize the system coverage. The decision-making process is supported by a binary integer mathematical programming model, and the instances are built from intercity travel surveys that provide realistic data based on travel demand. The developed decision support system prototype provides a recommendation about where virtual bike stations should be located during peak hours and improve general availability by more than 37%. Moreover, when the system's users participate in the relocation of bicycles, the model can eliminate up to 80% of the CO2 emissions and nearly 50% of the operational costs associated with the relocation process.

8.
Int. j. morphol ; 40(6): 1630-1640, dic. 2022. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1421802

RESUMO

La equinococosis quística (EQ) a pesar de ser una enfermedad endémica en diversos lugares del planeta, presenta pocos estudios morfológicos y cuantitativos de las estructuras fundamentales del Echinococcus granulosus en humanos, en especial de los protoescólices. El objetivo de este estudio fue analizar morfocuantitativamente protoescólices y otras estructuras fundamentales de E. granulosus obtenidos de hospederos humanos. Estudio de corte transversal. Se estudiaron 8 especímenes de EQ hepática humana, aplicando un muestreo no probabilístico por conveniencia. Se evaluó las capas quísticas, el líquido y la arenilla hidatídica. Las capas fueron fijadas en formaldehido tamponado a 10 % y procesadas para su inclusión en paraplast. Se realizaron cortes de 5 µm de grosor y fueron teñidas con H-E para su análisis con microscopía óptica. El líquido y arenilla fueron centrifugados y al sedimento obtenido se le realizó análisis directo para determinar las medidas morfométricas de los protoescólices y de los ganchos grandes y pequeños. Se utilizó estadística descriptiva. De los 8 quistes estudiados, 6 eran quistes univesicular, uno multivesicular y un quiste abscedado, cuyas capas laminada y germinativa se encontraban bien definidas. Las vesículas prolígeras presentaban forma redondeada con protoescólices en su interior. Los protoescólices invaginados presentaron un largo y ancho promedio de 140,8 ± 34,3 µm y 106,2 ± 29,5 µm, respectivamente; y los desarrollados un largo de 237,2 ± 53,0 µm y ancho de 128,7 ± 32,0 µm. Los ganchos rostelares presentaron contornos suaves distribuidos en dos filas regulares. El promedio del largo total de los ganchos grandes y pequeños fue 20,1 ± 2,7 µm; el promedio del ancho total fue 7,4 ± 1,2 µm. En conclusión, las características morfocuantitativas de los ganchos de E. granulosus en humanos, son distintos a otras especies hospederas intermediarias y de otros Echinococcus spp. Es posible que el abandono del estado de resistencia de los protoescólices invaginado hasta su desarrollo genere implicancias epidemiológicas de interés.


SUMMARY: Although cystic echinococcosis (CE) is an endemic disease in several parts of the world, few morphological and quantitative studies of the fundamental structures of Echinococcus granulosus in humans, especially protoscolices. The aim of this study was to perform a morphoquantitative analysis of protoescolex and other fundamental structures of E. granulosus from human hosts. Cross- sectional study. Eight human hepatic EQ specimens were studied, applying non-probabilistic convenience sampling. Cystic layers, fluid and hydatid grit were evaluated. The layers were fixed in 10% buffered formaldehyde and processed for embedding in paraplast. Slices of 5 µm thickness were made and stained with H-E for light microscopic analysis. The liquid and grit were centrifuged and the sediment obtained was analyzed directly to determine the morphometric measurements of the protoscolices and the large and small hooks. Descriptive statistics were used. Of the 8 cysts studied, 6 were univesicular cysts, one multivesicular and one abscessed cyst, whose lamellar and germinative layers were well defined. The proligerous vesicles had a rounded shape with protoscolices inside. The invaginated protoscolices had an average length and width of 140.8 ± 34.3 µm and 106.2 ± 29.5 µm, respectively; and the developed ones had a length of 237.2 ± 53.0 µm and width of 128.7 ± 32.0 µm. The rostellar hooks presented smooth contours distributed in two regular rows. The average total length of the large and small hooks was 20.1 ± 2.7 µm; the average total width was 7.4 ± 1.2 µm. In conclusion, the morphoquantitative characteristics of E. granulosus hooks in humans are distinct from other intermediate host species and from other Echinococcus spp. It is possible that the abandonment of the resistance state of the invaginated protoscolices until their development generates epidemiological implications of interest.


Assuntos
Humanos , Animais , Echinococcus granulosus/anatomia & histologia , Equinococose/parasitologia , Estudos Transversais
9.
Polymers (Basel) ; 14(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35746026

RESUMO

Poly(vinyl alcohol) (PVA) displays ice recrystallization inhibition (IRI) properties as many antifreeze proteins found in cold tolerant organisms. The molecular architecture and composition (molecular weight and distribution of pendant OH and acetate groups) have been studied to improve the antifreezing properties of PVA, suggesting that the molecular architecture of PVA plays an important role in IRI activity. The present work deals with the preparation of PVA microparticles using an alkaline treatment. The effect of PVA molecular weight on the morphology and antifreezeing properties of PVA microparticles was investigated. The antifreezeing property of PVA microparticles on the susceptibility of flower bud tissues to freeze damage was also evaluated. The alkaline treatment of an aqueous PVA solution produced stable polymer chain aggregates with spherical shapes. The average size of the PVA microparticles increased significantly with the increasing molecular weight of the PVA macromolecule precursor. The PVA microparticles inhibited the growth of ice crystals and blocked ice growth at concentrations as low as 0.01 % w/v. The effect of impeding ice crystal growth by preventing the joining of adjacent ice crystals is attributed to the larger size of the PVA particles adsorbed on the ice surface compared to the aggregated PVA macromolecules in saline solution. The thermal hysteresis activity of PVA macromolecules and microparticles was not detected by differential scanning calorimetry analysis. The PVA microparticles reduced the incidence of freeze injuries in flower bud tissues by 55% and their application, considering the low toxicity of PVA, has a high potential for freeze protection in fruit crops.

10.
Acta Parasitol ; 67(1): 161-185, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34264444

RESUMO

INTRODUCTION: The aim of this study was to develop a synthesis of the evidence available regarding verified E. granulosus sensu lato (s.l.) genotypes in different species worldwide. MATERIAL AND METHODS: A systematic review was performed including studies concerning genotypes of E. granulosus s.l. without language or genotyped method restriction, published between 1990 and 2020. A systematic search was carried out in Trip Database, BIREME, SciELO, LILACS, IBECS, PAHO-WHO, EMBASE, PubMed, Scopus, and WoS. Variables of interest were year of publication, country, number of samples, and hosts; genotypes, molecular marker, haplotypes and molecular biology techniques used. Descriptive statistics were applied. RESULTS: 2411 articles were analyzed, however 135 met the selection criteria, representing 8643 liver and lung samples. Of the samples selected 24% were human, the remaining samples pertained to non-human animal hosts; cattle and sheep prevailed with 28.6% and 26.6% of the studied samples, respectively. The reported evidence is mainly from Iran, Turkey, Argentina, China and Chile; with 50, 11, 6, 6 and 5 studies, respectively, published between 1992 and 2020 [most frequently during 2015-2020 (76/135 studies; 56.3%)]. The mitochondrial gene cox1 was generally sequenced and informative (91.8%). Genotypes most frequently identified were E. granulosus sensu stricto (s.s.) (83.2%). CONCLUSIONS: Based on this overall evidence, it can be concluded that publications related to genotypes of E. granulosus s.l. are heterogeneous. E. granulosus ss accounts for the vast majority of the global burden of E. granulosus s.l. worldwide. Further studies including larger number of cases and adequate internal validity are required to specify the distribution of genotypes in various host species. TRIAL REGISTRATION: PROSPERO CRD42018099827.


Assuntos
Equinococose , Echinococcus granulosus , Animais , Bovinos , Equinococose/parasitologia , Equinococose/veterinária , Echinococcus granulosus/genética , Genes Mitocondriais , Genótipo , Humanos , Ovinos
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