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1.
Ann Hepatol ; 22: 100237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32835861

RESUMO

Infected hepatic echinococcosis (IHE), defined as a cystic infection, and the development of a liver abscess may be a complication in the natural history of hepatic echinococcosis. The aim of this study was to review the evidence available related to clinical, therapeutic, and prognostic aspects of IHE. We conducted a systematic review. Trip Database, BIREME-BVS, SciELO, LILACS, IBECS, PAHO-WHO; WoS, EMBASE, SCOPUS and PubMed were consulted. Studies related to IHE in humans, without language restriction, published between 1966 and 2020 were considered. Variables studied were publication year, geographical origin of the samples, number of patients, therapeutic and prognosis aspects, and methodological quality (MQ) for each article. Descriptive statistics was applied. Subsequently, weighted averages (WA) of the MQ of each article were calculated for each variable of interest. 960 related articles were identified; 47 fulfilled selection criteria, including 486 patients with a median age of 48 years, 51.6% being male. The largest proportion of articles were from Spain, India, and Greece (36.1%). Mean cyst diameter was 14.1 cm, and main location was right liver lobe (74.0%). WA for morbidity, mortality, hospital stay, and follow-up were 28.5%, 7.4%, 8.5 days and 14.8 months, respectively. The most common causative microorganisms of superinfection isolated were Enterobacteriaceae. An association with cholangitis was reported in 13.4% of cases. Mean MQ of the 47 articles included was 7.6 points. We can conclude that the information related to IHE is scarce and scattered throughout articles of small casuistry and poor quality, and consequently does not provide strong evidence.


Assuntos
Equinococose Hepática/diagnóstico , Equinococose Hepática/terapia , Equinococose Hepática/mortalidade , Humanos , Prognóstico
2.
J Clin Lab Anal ; 33(9): e23001, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31441123

RESUMO

BACKGROUND: Identification and characterization of genetic variants and their effects on human health may allow to establish relationships between genetic background and susceptibility to developing cardiovascular diseases. LDLR and PCSK9 polymorphisms have been associated with higher lipid levels and risk of cardiovascular diseases. Thus, the main aim of this study was to evaluate genotype distribution and relative allelic frequency of LDLR rs5925 (1959C > T) and PCSK9 rs505151 (23968 A > G) genetic variants and their effects on lipid levels of healthy subjects from northern Chile. METHODS: A total of 178 healthy individuals were recruited for this study. The genotyping of rs5925 (LDLR) and rs505151 (PCSK9) polymorphisms was performed by PCR-RFLP and qPCR, respectively. In addition, glucose and lipid levels were determined and associated with the genetic data. RESULTS: Genotype distribution for LDLR rs5925 polymorphism was as follows: CC = 19%; CT = 53%; and TT = 28% (HWE: χ2  = 0.80; P = .37), and for PCSK9 rs505151 genetic variant was as follows: AA = 93%; AG = 7%; and GG = 0% (HWE: χ2  = 0.22; P = .64). The frequency of T (rs5925) and G (rs505151) mutated alleles was 0.55 and 0.03, respectively. Data showed that individuals carrying LDLR mutated allele (T) presented lower values of total cholesterol, triglycerides, and LDL-cholesterol when compared to CC homozygous genotype (P < .05). Subgroup analysis revealed that women carrying the PCSK9 mutated allele (G) exhibited higher values of total cholesterol, triglycerides, HDL-C, and LDL-C when compared to male group carrying the same genotype (P < .05). CONCLUSIONS: The effect of LDLR rs5925 and PCSK9 rs505151 gene polymorphisms on lipid levels is associated with gender among healthy subjects from northern Chile.


Assuntos
Predisposição Genética para Doença , Lipídeos/sangue , Polimorfismo de Nucleotídeo Único/genética , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Adulto , Chile , Feminino , Frequência do Gene/genética , Humanos , Masculino , Adulto Jovem
3.
Arch Pharm (Weinheim) ; 351(5): e1800024, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29611620

RESUMO

With the purpose of expanding the structural variety of chemical compounds available as pharmacological tools for the treatment of Alzheimer's disease, we synthesized and evaluated a novel series of indole-benzoxazinones (Family I) and benzoxazine-arylpiperazine derivatives (Family II) for potential human acetylcholinesterase (hAChE) inhibitory properties. The most active compounds 7a and 7d demonstrated effective inhibitory profiles with Ki values of 20.3 ± 0.9 µM and 20.2 ± 0.9 µM, respectively. Kinetic inhibition assays showed non-competitive inhibition of AChE by the tested compounds. According to our docking studies, the most active compounds from both series (Families I and II) showed a binding mode similar to donepezil and interact with the same residues.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Benzoxazinas/farmacologia , Inibidores da Colinesterase/farmacologia , Piperazinas/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Benzoxazinas/síntese química , Benzoxazinas/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Donepezila , Desenho de Fármacos , Humanos , Indanos/farmacologia , Simulação de Acoplamento Molecular , Piperazinas/síntese química , Piperazinas/química , Piperidinas/farmacologia , Ligação Proteica , Relação Estrutura-Atividade
4.
Arch Pharm (Weinheim) ; 347(3): 174-84, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24339227

RESUMO

A series of functionalized indolylalkylarenes 3-16(a and b) were synthesized and their affinities for the serotonin transporter were investigated in vitro. Compounds 3-12(a and b) were obtained by nucleophilic substitution of 3-(1H-indol-3-yl)propyl-4-methylbenzenesulfonates 2(a and b) with a series of azaheterocycles. Compounds 14-16(a and b) were prepared in a two-step sequence by reaction of 3-(1H-indol-3-yl)-2-methylpropanal with substituted 1,2-phenylenediamines. Compounds 3b, 4b, and 5b showed good binding affinities (K(i) = 33.0, 48.0, and 17 nM, respectively). The other synthesized compounds showed moderate or no affinity in the binding studies.


Assuntos
Indóis/síntese química , Indóis/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/síntese química , Inibidores Seletivos de Recaptação de Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Células HEK293 , Humanos , Indóis/farmacologia , Estrutura Molecular , Proteínas da Membrana Plasmática de Transporte de Serotonina/efeitos dos fármacos , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Relação Estrutura-Atividade , Transfecção
5.
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.

6.
Appl Plant Sci ; 12(4): e11588, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39184202

RESUMO

Premise: Cytotaxonomy employs chromosome visualization to study organismal relationships and evolution. Despite the critical value of cytogenetic data, cytotypes are lacking for many plant groups. Here, we present an improved approach for visualizing mitotic chromosomes in ferns, a key lineage of land plants, using the dividing cells of unfurling croziers (fiddleheads). Methods and Results: Our modified mitotic chromosome preparation incorporates a brief pectinase-cellulase pretreatment, as well as colchicine fixation and the Feulgen reaction to improve the staining and separation of mitotic chromosomes. To demonstrate this easy and efficient assessment, we determined the sporophytic (2n) chromosome number for three fern species: Cheilanthes mollis (2n = 60), Cheilanthes hypoleuca (2n = 120), and Nephrolepis cordifolia (2n = 82). Conclusions: The new method presented here improves visualizations of mitotic chromosomes from the dividing nuclei of young fern croziers. Fiddleheads are widely accessible in nature and in living collections worldwide, and this modified approach increases their suitability for fern cytotaxonomic studies.

7.
Rev Chilena Infectol ; 30(3): 252-7, 2013 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-23877776

RESUMO

BACKGROUND: Leptospirosis, a bacterial disease of worldwide distribution, affects various animals and is considered a zoonosis. It can be transmitted directly or indirectly, mainly through contact with the carrier's urine and entering the body through mucous membranes or skin. In the city of Temuco, there are no epidemiological studies of canine leptospirosis and the country data are scarce. OBJECTIVE: To determine the prevalence of leptospirosis in stray dogs of the city of Temuco. MATERIAL AND METHODS: In a cross- sectional study, 400 dogs admitted to Temuco Kennel during the year 2011 were sampled. Blood samples were analyzed using a modified commercial ELISA kit. RESULTS: The prevalence of leptospirosis was 21.3%. Positive cases were concentrated in dogs 5 to 8 years of age, independent of gender. DISCUSSION: The high prevalence found demonstrates the need for further studies to better understand the epidemiology of the disease and to establish prevention and control measures.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças do Cão/epidemiologia , Leptospira/imunologia , Leptospirose/veterinária , Animais , Chile/epidemiologia , Estudos de Coortes , Estudos Transversais , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leptospirose/epidemiologia , Masculino , Prevalência
8.
Rev Chilena Infectol ; 30(4): 395-401, 2013 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-24248108

RESUMO

BACKGROUND: Brucella canis is responsible for brucellosis in dogs, causing reproductive disorders and is considered a zoonoses, as described in several countries. The epidemiological data are scarce in our country. AIM: To determine the prevalence of Brucella canis in vague dogs in Temuco city and housed in the Temuco Kennel. METHODS: Quantitative and cross-section study. We used 400 samples of dogs of both sexes, different ages and mainly mixed race, which were tested by immunochromatography. RESULTS: Antibodies were detected in 4 samples Brucella canis which represented 1% of the population studied, 2 females (0.5%) and 2 males (0.5%). DISCUSSION: We conclude that dogs are infected by B. canis in a low range but remains a risk condition to the health of the human population if not maintained adequate sanitary control of pets, like vague dogs.


Assuntos
Brucella canis/imunologia , Brucelose/veterinária , Doenças do Cão/epidemiologia , Animais , Brucelose/diagnóstico , Brucelose/epidemiologia , Chile/epidemiologia , Cromatografia de Afinidade/veterinária , Estudos Transversais , Doenças do Cão/diagnóstico , Doenças do Cão/microbiologia , Cães , Feminino , Masculino , Prevalência
9.
PLoS Negl Trop Dis ; 17(12): e0011813, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38064500

RESUMO

BACKGROUND: Cystic echinococcosis (CE) is an endemic disease in southern Chile. The aim of this study was to ascertain the prevalence of CE among relatives of patients who underwent surgical intervention for this disease in Cautín, a province of southern Chile. METHODOLOGY/PRINCIPAL FINDINGS: Cross-sectional study. Relatives of patients who underwent surgery for hepatic echinococcosis (HE), who lived at the same address, during the period 2000-2020 were studied. A total of 288 relatives of 322 patients who underwent surgery for HE participated in a CE screening. All these relatives were interviewed and underwent abdominal ultrasonography, chest X-ray and immunodiagnostic studies (relatives who had been diagnosed with or had undergone surgery for CE were excluded). Descriptive statistics were applied. Prevalence calculation, odds ratio (OR), and their respective 95% confidence intervals (95% CI) were determined. Abdominal or thoracic CE was verified in 42 relatives of subjects operated on for HE (mean age 41±8 years; 73.8% women; 38.1% of cases had two or more cysts), all of them new and asymptomatic cases. CE was detected in the lungs, liver, peritoneum, and spleen in 16.7%; 71.4%; 7.1%; and 4.8%, respectively. The overall prevalence of EQ during the studied time period was 14,6% (17.9% and 12.3% in relatives of first and second degree respectively (OR:1.56; CI 95%: 0.81; 3.01). CONCLUSION/SIGNIFICANCE: There is a high prevalence of CE in relatives of patients undergoing surgery by this disease in the province of Cautín, Chile.


Assuntos
Equinococose Hepática , Equinococose , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Equinococose Hepática/diagnóstico por imagem , Equinococose Hepática/epidemiologia , Equinococose Hepática/cirurgia , Prevalência , Estudos Transversais , Equinococose/epidemiologia , Equinococose/cirurgia , Equinococose/diagnóstico
10.
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.

11.
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
12.
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
13.
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.

14.
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.

15.
Cureus ; 14(12): e32101, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36601154

RESUMO

BACKGROUND: Type I lateral compression pelvic fractures (LC-I) have historically been treated conservatively. Inferior outcomes in a distinctive subset of these injuries have been reported, therefore their management has shifted towards surgery. Revisiting the historical series of LC-I allows us to determine whether non-operative management of these unstable patterns results in poorer outcomes. The objective was to evaluate the differences in the rehabilitation progress, fracture consolidation, and displacement in non-operatively treated LC-I fractures that would be considered unstable using today's Association of Osteosynthesis (AO) criteria. METHODS: We conducted a retrospective review of conservatively treated LC-I injuries in a single-level I trauma center between June 2010 and June 2014. Patients were distributed in stable (group A) and unstable (group B) groups according to the 2018 AO classification. Time to walk independently (TWI), time to return to work (TRW), fracture consolidation, and displacement were analyzed. RESULTS: 34 patients, mean age of 45.5 ±14.5 years, were included. Mean TWI in groups A and B were 71.2 ±31.9 and 105.9 ±50.9 days (p=0.027). Mean TRW was 106 ±51.3 and 157 ±84 days in groups A and B, respectively (p=0.038). A difference in mean TWI and TRW of 34.7 and 51.3 days between groups was observed. No significant differences in fracture consolidation or displacement were observed. CONCLUSION: Unstable fractures presented significantly longer TWI and TRW. The revised AO classification contributes to the identification of fracture patterns that correlate with prolonged rehabilitation in which additional treatment strategies might be considered.

16.
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
17.
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.

18.
J Orthop Surg Res ; 16(1): 661, 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34742331

RESUMO

BACKGROUND: Failure of fixation (FF) in pubic symphysis diastasis (SD) ranges between 12 and 75%, though whether it influences functional outcomes is still debated. The objective of this study is to evaluate the impact of anterior pelvic plate failure and loss of reduction on Majeed's functional scores. METHODS: Single center retrospective review of consecutive patients with acute SD treated by means of anterior pubic plating. Thirty-seven patients with a mean age 45.7 ± 14.4 years were included. Demographics, AO classification, pelvic fixation and secondary procedures were recorded. Majeed's functional scores at minimum 6 months follow-up were compared according to the presence of FF and loss of reduction. RESULTS: Fifteen patients presented FF. Eight presented an additional loss of symphyseal reduction. Mean Majeed´s score (MMS) in patients with and without FF was 64.4 ± 13.04 and 81.8 ± 15.65, respectively (p = 0.0012). Differences in MMS in patients without FF and those with FF and maintained or loss of anterior reduction were 11.3 [70.5 vs 81.8] (p = 0.092) and 22.7 [59.1 vs 81.8] (p = 0.001), respectively. Significant association of FF with AO classification was noted. (OR 12.6; p = 0.002). CONCLUSIONS: Differences in MMS in the analyzed groups suggest that loss of reduction might be more relevant than failure of the anterior osteosynthesis in functional outcomes.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Diástase da Sínfise Pubiana , Sínfise Pubiana , Adulto , Placas Ósseas , Fixação Interna de Fraturas , Humanos , Pessoa de Meia-Idade , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/cirurgia , Sínfise Pubiana/diagnóstico por imagem , Sínfise Pubiana/cirurgia , Diástase da Sínfise Pubiana/diagnóstico por imagem , Diástase da Sínfise Pubiana/epidemiologia , Diástase da Sínfise Pubiana/cirurgia , Estudos Retrospectivos
19.
Front Genet ; 12: 640956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616421

RESUMO

Characterization of allelic variants is relevant to demonstrate associations among genetic background and susceptibility to develop cardiovascular diseases, which are the main cause of death in Chile. Association of APOB, APOE, and MTHFR polymorphisms with higher lipid levels and the risk of developing hypertension and cardiovascular diseases have been described. Thus, the aim of this study was to assess genotype distribution and relative allelic frequency of ApoB rs693, ApoE rs7412, ApoE rs429358, MTHFR rs1801131, and MTHFR rs1801133 allelic variants and their effects on lipid profile in young healthy men and women from Northern Chile. A group of 193 healthy subjects were enrolled for this study. Genotyping of rs693 (APOB), rs7412 and rs429358 (APOE), and rs1801131 and rs1801133 (MTHFR) polymorphisms were performed by real time PCR. In addition, lipid profiles were determined and associated to genetic data. The genotype distribution was APOB rs693 (CC = 37%, CT = 41%, and TT = 22%), APOE rs7412/rs429358 (E4 = 0.06, E3 = 0.91, and E2 = 0.03), MTHFR rs1801131 (AA = 57%, AC = 30%, and CC = 13%), and MTHFR rs1801133 (CC = 20%, CT = 47%, and TT = 33%). The association of the genetic variants with plasma lipid levels showed that women, but not men, carrying APOB mutated allele (T) and Apo E4 allele presented lower values of total cholesterol when compared with C/C homozygous genotype or E3 allele, respectively (p < 0.05). In addition, a subgroup analysis revealed that ApoB C/C homozygous women exhibited higher values of HDL-C when compared with men carrying identical genotype (p < 0.01). On the other hand, women carrying E4 allele exhibited lower values of triglycerides when compared with male carrying identical genotype (p < 0.05). Finally, women carrying mutate allele (C) for MTHFR rs1801131 showed lower levels of triglycerides when compared with A/A homozygous genotype (p < 0.05) and lower levels of LDL-C for MTHFR rs1801133 in females carrying (T) allele when compared with males carrying identical genotype (p < 0.05). In summary, the present data showed that APOB, APOE, and MTHFR single nucleotide polymorphisms are associated to lipid levels in a gender-dependent manner among healthy subjects from Northern Chile, especially in women.

20.
Zebrafish ; 18(5): 326-329, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34491117

RESUMO

Cytogenetic studies in marine fish are scarce, and elemental cytogenetic information is available for not >2% of the species. Traditional cytogenetic methods require living individuals for their application, making the analysis of marine ichthyofauna very difficult. In this study, we present a detailed new protocol to obtain cytogenetic preparations from marine fish, through access to specimens in postmortem condition. The application of this protocol made it possible to access elemental cytogenetic information (diploid number) in six native species of the South Pacific Ocean, representative of five orders. In this way, we provide a new low-cost methodological tool for focused or large-scale cytogenetic analysis, both in economically important, native, or threatened species.


Assuntos
Peixe-Zebra , Animais , Análise Citogenética , Citogenética/métodos
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