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1.
J Nutr ; 153(4): 979-987, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36870540

RESUMO

BACKGROUND: Post-translational modifications are key factors in the modulation of nuclear protein functions controlling cell physiology and an individual's health. OBJECTIVES: This study examined the influence of protein restriction during the perinatal period on the nuclear O-N-acetylgalactosamine (O-GalNAc) glycosylation of cells from the liver and parts of the brain in the rat. METHODS: Pregnant Wistar rats were divided into 2 groups on day 14 of pregnancy and fed ad libitum 1 of 2 isocaloric diets containing 24% (well-fed) or 8% (protein-restricted diet) casein until the end of the experiment. Male pups were studied after weaning at 30 d of life. Animals and their organ/tissues (liver, cerebral cortex, cerebellum and hippocampus) were weighed. Cell nuclei were purified, and the presence in nucleus and cytoplasm of all factors required for the initiation of O-GalNAc glycan biosynthesis, i.e., the sugar donor (UDP-GalNAc), enzyme activity (ppGalNAc-transferase) and the glycosylation product (O-GalNAc glycans), were evaluated by western blotting, fluorescent microscopy, enzyme activity, enzyme-lectin sorbent assay and mass spectrometry. RESULTS: The perinatal protein deficit reduced progeny weight, as well as the cerebral cortex and cerebellum weight. UDP-GalNAc levels in the cytoplasm and nuclei of the liver, the cerebral cortex, cerebellum, or hippocampus were not affected by the perinatal dietary protein deficits. However, this deficiency affected the ppGalNAc-transferase activity localized in the cerebral cortex and hippocampus cytoplasm as well as in the liver nucleus, thus reducing the "writing" ppGalNAc-transferase activity of O-GalNAc glycans. In addition, liver nucleoplasm from protein-restricted offspring revealed a significant reduction in the expression of O-GalNAc glycans on important nuclear proteins. CONCLUSIONS: Our results report an association between the consumption of a protein-restricted diet by the dam and her progeny with the modulation in the offspring' liver nuclei O-GalNAc glycosylation, which may ultimately regulate nuclear protein functions.


Assuntos
Núcleo Celular , Dieta com Restrição de Proteínas , Masculino , Ratos , Animais , Glicosilação , Ratos Wistar , Polissacarídeos , Fígado , Proteínas Nucleares , Encéfalo , Transferases , Difosfato de Uridina
2.
Ann Intern Med ; 175(1): 36-45, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34748376

RESUMO

BACKGROUND: Recent reports showed that the protective effect of flexible sigmoidoscopy (FS) screening was maintained up to17 years, although differences were reported by sex. OBJECTIVE: To assess long-term reduction of colorectal cancer (CRC) incidence and mortality after a single FS screening. DESIGN: Parallel randomized controlled trial. (ISRCTN registry number: 27814061). SETTING: 6 centers in Italy. PARTICIPANTS: Persons aged 55 to 64 years expressing interest in having FS screening if invited, recruited from 1995 to 1999 and followed until 2012 (incidence) and 2014 to 2016 (mortality). INTERVENTION: Eligible persons were randomly assigned (1:1 ratio) to either the once-only FS screening group or control (usual care) group. MEASUREMENTS: Incidence and mortality rate ratios (RRs) and rate differences. RESULTS: A total of 34 272 persons (17 136 in each group) were included in the analysis; 9911 participants had screening in the intervention group. Median follow-up was 15.4 years for incidence and 18.8 years for mortality. Incidence of CRC was reduced by 19% (RR, 0.81 [95% CI, 0.71 to 0.93]) in the intention-to-treat (ITT) analysis, comparing the intervention with the control group, and by 33% (RR, 0.67 [CI, 0.56 to 0.81]) in the per protocol (PP) analysis, comparing participants screened in the intervention group with the control persons. Colorectal cancer mortality was reduced by 22% (RR, 0.78 [CI, 0.61 to 0.98]) in the ITT analysis and by 39% (RR, 0.61 [CI, 0.44 to 0.84]) in the PP analysis. Incidence of CRC was statistically significantly reduced among both men and women. Colorectal cancer mortality was statistically significantly reduced among men (ITT RR, 0.73 [CI, 0.54 to 0.97]) but not among women (ITT RR, 0.90 [CI, 0.59 to 1.37]). LIMITATION: Self-selection of volunteers from the general population sample targeted for recruitment may limit generalizability. CONCLUSION: The strong protective effect of a single FS screening for CRC incidence and mortality was maintained up to 15 and 19 years, respectively. PRIMARY FUNDING SOURCE: Italian Association for Cancer Research, Italian National Research Council, Istituto Oncologico Romagnolo, Fondo "E. Tempia," University of Milan, and Local Health Unit ASL-Torino.


Assuntos
Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/mortalidade , Detecção Precoce de Câncer/métodos , Sigmoidoscopia , Neoplasias Colorretais/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Análise de Intenção de Tratamento , Itália/epidemiologia , Estudos Longitudinais , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Sistema de Registros , Fatores Sexuais
3.
Pathologica ; 114(4): 295-303, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36136897

RESUMO

Objective: A common source of concern about digital pathology (DP) is that limited resolution could be a reason for an increased risk of malpractice. A frequent question being raised about this technology is whether it can be used to reliably detect Helicobacter pylori (HP) in gastric biopsies, which can be a significant burden in routine work. The main goal of this work is to show that a reliable diagnosis of HP infection can be made by DP even at low magnification. The secondary goal is to demonstrate that artificial intelligence (AI) algorithms can diagnose HP infections on virtual slides with sufficient accuracy. Methods: The method we propose is based on the Warthin-Starry (W-S) silver stain which allows faster detection of HP in virtual slides. A software tool, based on regular expressions, performed a specific search to select 679 biopsies on which a W-S stain was done. From this dataset 185 virtual slides were selected to be assessed by WSI and compared with microscopy slide readings. To determine whether HP infections could be accurately diagnosed with machine learning. AI was used as a service (AIaaS) on a neural network-based web platform trained with 468 images. A test dataset of 210 images was used to assess the classifier performance. Results: In 185 gastric biopsies read with DP we recorded only 4 false positives and 4 false negatives with an overall agreement of 95.6%. Compared with microscopy, defined as the "gold standard" for the diagnosis of HP infections, WSI had a sensitivity and specificity of 0.95 and 0.96, respectively. The ROC curve of our AI classifier generated on a testing dataset of 210 images had an AUC of 0.938. Conclusions: This study demonstrates that DP and AI can be used to reliably identify HP at 20X resolution.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Inteligência Artificial , Biópsia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/patologia , Humanos , Estômago/patologia
6.
Rev Esp Geriatr Gerontol ; 58(4): 101377, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37451199

RESUMO

OBJECTIVE: To analyze the characteristics of seriously ill elderly patients during the six waves of the COVID-19 pandemic. METHOD: Retrospective, observational and analytical study of patients over 70 years of age admitted to the ICU (March-2020 to March-2022). Patients were categorized into three groups based on age: 70-74 years; 75-79 years; and >80 years. A descriptive and comparative analysis of the sample was initially performed; and a 28-, 60- and 90-day survival analysis using the Kaplan-Meier method. Multivariate survival analysis was performed by fitting a Cox model. RESULTS: Of 301 patients, the lowest number of admissions occurred during the first wave (20 (6%)), compared to the wave with the highest number of admissions: the sixth wave (76 (25%)). The survival curves at 28 days, 60 days and 90 days showed a higher probability of survival in the younger age groups (P<.01 and P=.01, respectively). Troponin at admission (per unit, ng/l) showed a significant association with 28- and 60-day mortality (HR: 1.00; 95% CI: 1.00-1.01; P<.05). Taking the 1st wave of the pandemic as a reference, admission in the 3rd wave behaved as a protective factor against mortality at 28 and 60 days of follow-up (HR: 0.18; 95% CI: 0.02-0.64; P<.05; HR: 0.13; 95% CI: 0.02-0.64; P<.05, respectively). CONCLUSIONS: The time of admission and biomarkers, such as troponin, constitute prognostic markers independent of age in the elderly population.


Assuntos
COVID-19 , SARS-CoV-2 , Idoso , Idoso de 80 Anos ou mais , Humanos , COVID-19/epidemiologia , Mortalidade Hospitalar , Unidades de Terapia Intensiva , Pandemias , Estudos Retrospectivos , Troponina
7.
Med Clin (Barc) ; 161(5): 199-204, 2023 09 08.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37244858

RESUMO

BACKGROUND AND OBJECTIVE: Our study aims to compare the clinical and epidemiological characteristics, length of stay in the ICU, and mortality rates of COVID-19 patients admitted to the ICU who are fully vaccinated, partially vaccinated, or unvaccinated. PATIENTS AND METHODS: Retrospective cohort study (March 2020-March 2022). Patients were classified into unvaccinated, fully vaccinated, and partially vaccinated groups. We initially performed a descriptive analysis of the sample, a multivariable survival analysis adjusting for a Cox regression model, and a 90-day survival analysis using the Kaplan-Meier method for the death time variable. RESULTS: A total of 894 patients were analyzed: 179 with full vaccination, 32 with incomplete vaccination, and 683 were unvaccinated. Vaccinated patients had a lower incidence (10% vs. 21% and 18%) of severe ARDS. The survival curve did not show any differences in the probability of surviving for 90 days among the studied groups (p = 0.898). In the Cox regression analysis, only the need for mechanical ventilation during admission and the value of LDH (per unit of measurement) in the first 24 hours of admission were significantly associated with mortality at 90 days (HR: 5.78; 95% CI: 1.36-24.48); p = 0.01 and HR: 1.01; 95% CI: 1.00-1.02; p = 0.03, respectively. CONCLUSIONS: Patients with severe SARS-CoV-2 disease who are vaccinated against COVID-19 have a lower incidence of severe ARDS and mechanical ventilation than unvaccinated patients.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Humanos , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Retrospectivos , Unidades de Terapia Intensiva , Vacinação
8.
J Nanosci Nanotechnol ; 12(6): 4803-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905533

RESUMO

The purpose of this research work was to develop a textile finish based on the radical UV-curing of chitosan on textiles to confer antimicrobial properties. Chitosan is a biopolymer with unique properties such as biodegradability, non-toxicity, antimicrobial activity. In this work cotton or silk fabrics and synthetic filter fabrics were impregnated with an acid solution of chitosan added of the photoinitiator in the proper amount and cured at room temperature by exposure to UV lamp. Process conditions such as percentage add-on, dilution, chitosan-fabric contact time, irradiation time and power, were optimized. The antimicrobial activity of finished fabrics was tested according to ASTM E 2149-01 standard test performed with Escherichia Coli ATCC 8739. Moreover dyeing test with Turquoise Telon dye were carried out to evaluate the treatment homogeneity while the amino group content was determined by ninhydrin assay. Moreover on cotton and silk fabrics the treatment fastness to domestic laundering was tested, according to UNI EN ISO105-C01. Obtained results showed a strong antimicrobial activity conferred by the treatment, homogeneous on fabric surface. It is evident already at low add-on, without affecting the hand properties of natural fabrics and the filtration characteristics of the synthetic filter fabrics. Finally, washing fastness was better for samples prepared with a better penetration of chitosan inside the fibers.


Assuntos
Quitosana/química , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Têxteis/microbiologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Quitosana/efeitos da radiação , Teste de Materiais , Raios Ultravioleta
9.
J Mol Med (Berl) ; 100(10): 1387-1403, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36056254

RESUMO

Polypeptide N-acetylgalactosamine transferase 3 (ppGalNAc-T3) is an enzyme involved in the initiation of O-GalNAc glycan biosynthesis. Acting as a writer of frequent post-translational modification (PTM) on human proteins, ppGalNAc-T3 has key functions in the homeostasis of human cells and tissues. We review the relevant roles of this molecule in the biosynthesis of O-GalNAc glycans, as well as in biological functions related to human physiological and pathological conditions. With main emphasis in ppGalNAc-T3, we draw attention to the different ways involved in the modulation of ppGalNAc-Ts enzymatic activity. In addition, we take notice on recent reports of ppGalNAc-T3 having different subcellular localizations, highlight critical intrinsic and extrinsic functions in cellular physiology that are exerted by ppGalNAc-T3-synthesized PTMs, and provide an update on several human pathologies associated with dysfunctional ppGalNAc-T3. Finally, we propose biotechnological tools as new therapeutic options for the treatment of pathologies related to altered ppGalNAc-T3. KEY MESSAGES: ppGalNAc-T3 is a key enzyme in the human O-GalNAc glycans biosynthesis. enzyme activity is regulated by PTMs, lectin domain and protein-protein interactions. ppGalNAc-T3 is located in human Golgi apparatus and cell nucleus. ppGalNAc-T3 has a central role in cell physiology as well as in several pathologies. Biotechnological tools for pathological management are proposed.


Assuntos
N-Acetilgalactosaminiltransferases/metabolismo , Processamento de Proteína Pós-Traducional , Fenômenos Fisiológicos Celulares , Humanos , Peptídeos , Polissacarídeos/química , Transferases/metabolismo , Polipeptídeo N-Acetilgalactosaminiltransferase
10.
J Nanosci Nanotechnol ; 11(10): 8663-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22400240

RESUMO

In this study, cotton, polyester and polyamide fabrics were treated by radical or cationic ultraviolet curing of different commercial products conferring water and oil repellency. Moreover, radical ultraviolet curing of chitosan was applied to confer antimicrobial properties. The advantages of this technology are well known making it very interesting for industrial applications: energy savings, low environmental impact, simple, cheap and small equipment, high treatment speed. The polymerization was controlled through weight gain and gel content measurements, while the properties of hydro and oil repellency were determined in terms of contact angle, moisture adsorption and water vapor permeability. The polymer distribution on fabric surfaces was investigated by scanning electron microscopy and atomic force microscopy. However the fabrics treated with chitosan were subjected to the standard test for determining the antimicrobial activity. Finally the finished cotton samples were subjected to washing fastness tests.

11.
J Environ Sci (China) ; 22(3): 467-73, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20614792

RESUMO

Batch adsorption from aqueous solutions in a slightly basic medium of Methylene Blue, up to 2500 mg/L, onto synthetic magnesium silicate (Florisil) of three particle size ranges (mean diameters of 112, 200 and 425 microm) was compared to the corresponding adsorption onto activated carbon and Amberlite XAD-2. The best fit of the kinetic results was achieved by a pseudo second-order equation. The equilibrium data were found to be well represented by the Langmuir isotherm equation. Amberlite XAD-2, an unspecific adsorbent capable of adsorbing exclusively through a surface effect, exhibited a poor dye uptake, confirming that the adsorption mechanism on Florisil was due to electrostatic attraction and ion exchange. Moreover, the comparison between Florisil and the other adsorbents was performed on the basis of the evaluation of the surface area and pore volume occupied by the adsorbed dye.


Assuntos
Corantes/química , Silicatos de Magnésio/química , Azul de Metileno/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Poliestirenos/química , Propriedades de Superfície
15.
Biomacromolecules ; 9(10): 2819-25, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18798669

RESUMO

Keratin regenerated from wool and fibroin regenerated from silk were mixed in different proportions using formic acid as the common solvent. Both solutions were cast to obtain films and electrospun to produce nanofibers. Scanning electron microscopy investigation showed that, for all electrospun blends (except for 100% keratin where bead defects are present), the fiber diameter of the mats ranged from 900 (pure fibroin) to 160 nm (pure keratin). FTIR and DSC analysis showed that the secondary structure of the proteins was influenced by the blend ratios and the process used (casting or electrospinning). Prevalence of beta-sheet supramolecular structures was observed in the films, while proteins assembled in alpha-helix/random coil structures were observed in nanofibers. Higher solution viscosity, thinner filaments, and differences in the thermal and structural properties were observed for the 50/50 blend because of the enhanced interactions between the proteins.


Assuntos
Fibroínas/química , Queratinas/química , Calibragem , Varredura Diferencial de Calorimetria , Formiatos/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanopartículas/química , Nanotecnologia/métodos , Estrutura Secundária de Proteína , Proteínas/química , Seda/química , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier
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