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1.
Gastroenterol Hepatol ; 47(5): 481-490, 2024 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38154552

RESUMEN

BACKGROUND AND AIMS: Patients' perception of their bowel cleansing quality may guide rescue cleansing strategies before colonoscopy. The main aim of this study was to train and validate a convolutional neural network (CNN) for classifying rectal effluent during bowel preparation intake as "adequate" or "inadequate" cleansing before colonoscopy. PATIENTS AND METHODS: Patients referred for outpatient colonoscopy were asked to provide images of their rectal effluent during the bowel preparation process. The images were categorized as adequate or inadequate cleansing based on a predefined 4-picture quality scale. A total of 1203 images were collected from 660 patients. The initial dataset (799 images), was split into a training set (80%) and a validation set (20%). The second dataset (404 images) was used to develop a second test of the CNN accuracy. Afterward, CNN prediction was prospectively compared with the Boston Bowel Preparation Scale (BBPS) in 200 additional patients who provided a picture of their last rectal effluent. RESULTS: On the initial dataset, a global accuracy of 97.49%, a sensitivity of 98.17% and a specificity of 96.66% were obtained using the CNN model. On the second dataset, an accuracy of 95%, a sensitivity of 99.60% and a specificity of 87.41% were obtained. The results from the CNN model were significantly associated with those from the BBPS (P<0.001), and 77.78% of the patients with poor bowel preparation were correctly classified. CONCLUSION: The designed CNN is capable of classifying "adequate cleansing" and "inadequate cleansing" images with high accuracy.


Asunto(s)
Catárticos , Colonoscopía , Humanos , Colonoscopía/métodos , Femenino , Masculino , Persona de Mediana Edad , Catárticos/administración & dosificación , Estudios Prospectivos , Anciano , Redes Neurales de la Computación , Adulto , Sensibilidad y Especificidad , Inteligencia Artificial
2.
World J Microbiol Biotechnol ; 40(10): 318, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39261393

RESUMEN

Two strains of Yarrowia lipolytica (CBS 2075 and DSM 8218) were first studied in bioreactor batch cultures, under different controlled dissolved oxygen concentrations (DOC), to assess their ability to assimilate aliphatic hydrocarbons (HC) as a carbon source in a mixture containing 2 g·L-1 of each alkane (dodecane and hexadecane), and 2 g·L-1 hexadecene. Both strains grew in the HC mixture without a lag phase, and for both strains, 30 % DOC was sufficient to reach the maximum values of biomass and lipids. To enhance lipid-rich biomass and enzyme production, a pulse fed-batch strategy was tested, for the first time, with the addition of one or three pulses of concentrated HC medium. The addition of three pulses of the HC mixture (total of 24 g·L-1 HC) did not hinder cell proliferation, and high protease (> 3000 U·L-1) and lipids concentrations of 3.4 g·L-1 and 4.3 g·L-1 were achieved in Y. lipolytica CBS 2075 and DSM 8218 cultures, respectively. Lipids from the CBS 2075 strain are rich in C16:0 and C18:1, resembling the composition of palm oil, considered suitable for the biodiesel industry. Lipids from the DSM 8218 strain were predominantly composed of C16:0 and C16:1, the latter being a valuable monounsaturated fatty acid used in the pharmaceutical industry. Y. lipolytica cells exhibited high intrinsic surface hydrophobicity (> 69 %), which increased in the presence of HC. A reduction in surface tension was observed in both Y. lipolytica cultures, suggesting the production of extracellular biosurfactants, even at low amounts. This study marks a significant advancement in the valorization of HC for producing high-value products by exploring the hydrophobic compounds metabolism of Y. lipolytica.


Asunto(s)
Alcanos , Alquenos , Técnicas de Cultivo Celular por Lotes , Biomasa , Reactores Biológicos , Medios de Cultivo , Yarrowia , Yarrowia/crecimiento & desarrollo , Yarrowia/metabolismo , Alcanos/metabolismo , Reactores Biológicos/microbiología , Medios de Cultivo/química , Alquenos/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos/análisis , Lípidos/biosíntesis , Lípidos/análisis , Oxígeno/metabolismo , Metabolismo de los Lípidos
3.
Crit Rev Biotechnol ; 42(2): 163-183, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34157916

RESUMEN

Due to its physiological and enzymatic features, Yarrowia lipolytica produces several valuable compounds from a wide range of substrates. Appointed by some authors as an industrial workhorse, Y. lipolytica has an extraordinary ability to use unrefined and complex low-cost substrates as carbon and nitrogen sources, aiding to reduce the waste surplus and to produce added-value compounds in a cost-effective way. Dozens of review papers regarding Y. lipolytica have been published till now, proving the interest that this yeast arouses in the scientific community. However, most of them are focused on metabolic pathways involved in substrates assimilation and product formation, or the development of synthetic biology tools in order to obtain engineered strains for biotechnological applications. This paper provides an exhaustive and up-to-date revision on the application of Y. lipolytica to valorize liquid effluents and solid wastes and its role in developing cleaner biotechnological approaches, aiming to boost the circular economy. Firstly, a general overview about Y. lipolytica is introduced, describing its intrinsic features and biotechnological applications. Then, an extensive survey of the literature regarding the assimilation of oily wastes (waste cooking oils, oil cakes and olive mill wastewaters), animal fat wastes, hydrocarbons-rich effluents, crude glycerol and agro-food wastes by Y. lipolytica strains will be discussed. This is the first article that brings together the environmental issue of all such residues and their valorization as feedstock for valuable compounds production by Y. lipolytica. Finally, it will demonstrate the potential of this non-conventional yeast to be used as a biorefinery platform.


Asunto(s)
Yarrowia , Animales , Biotecnología , Glicerol , Redes y Vías Metabólicas , Residuos Sólidos
4.
Appl Microbiol Biotechnol ; 106(8): 2869-2881, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35394162

RESUMEN

Microbial lipids-derived biodiesel is garnering much attention owing to its potential to substitute diesel fuel. In this study, lipid accumulation by Yarrowia lipolytica from volatile fatty acids (VFAs) was studied in a lab-scale stirred tank bioreactor. In batch cultures, Y. lipolytica NCYC 2904 was able to grow in 18 g·L-1 of VFAs (acetate, propionate, and butyrate), and the addition of a co-substrate (glucose) led to a fivefold improvement in lipid concentration. Furthermore, the two-stage batch culture (growth phase in glucose (1st stage) followed by a lipogenic phase in VFAs (2nd stage)) was the best strategy to obtain the highest lipid content in the cells (37%, w/w), with aeration conditions that kept dissolved oxygen concentration between 40% and 50% of saturation during the lipogenic phase. The estimated fuel properties of biodiesel produced from Y. lipolytica NCYC 2904 lipids are comparable with those of the biodiesel produced from vegetable oils and are in accordance with the international standards (EN 14214 and ASTM D6751). The cultivation strategies herein devised enable a sustainable, eco-friendly, and economical production of microbial lipids, based on feedstocks such as VFAs that can be derived from the acidogenic fermentation of organic wastes. KEY POINTS: • Addition of glucose to VFAs enhances lipids in Y. lipolytica in batch cultures • Two-stage batch culture - growth in glucose followed by VFAs pulse - rises lipids • Dissolved oxygen of 40-50% of saturation is crucial at the lipogenic phase.


Asunto(s)
Yarrowia , Técnicas de Cultivo Celular por Lotes , Biocombustibles , Ácidos Grasos/química , Ácidos Grasos Volátiles/química , Glucosa , Lípidos , Oxígeno , Aceites de Plantas , Polifenoles
5.
Arch Biochem Biophys ; 693: 108538, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-32810478

RESUMEN

Oligosaccharyltransferase (OST) complex catalyzes the N-glycosylation of nascent polypeptides in the endoplasmic reticulum. Glycoproteins are critical for normal cell-cell interactions, especially during an immune response. Abnormal glycosylation is an insignia of several inflammatory diseases. However, the mechanisms that regulate the differential N-glycosylation are not fully understood. The OST complex can be assembled with one out of two catalytic subunits, STT3A or STT3B, which have different enzymatic properties. In this work, we investigated the expression of STT3A and STT3B in several mouse models such as a crossbreeding of normal and abortion-prone mice and an intestinal inflammation model. These animals were either exposed or not to acoustic stress (acute or chronic). The expression of the isoforms was analysed by immunohistochemistry and protein immunoblot. Finally, we investigated the gene regulatory elements employing public databases. Results demonstrated that inflammation alters the balance between the expression of both isoforms in the affected tissues. In homoeostatic conditions, STT3A expression predominates over STT3B, especially in epithelial cells. This relation is reversed as a consequence of inflammation. An increase in STT3B activity was associated to the generation of mannose-rich N-glycans. Accordingly, this type of N-glycans were found to decorate diverse inflamed tissues. The STT3A and STT3B genes are differentially regulated, which could account for the differences in the expression levels observed here. Our results support the idea that these isoforms could play different roles in cellular physiology. This study opens the possibility of studying the STT3A/STT3B expression ratio as a biomarker in acute inflammation or chronic diseases.


Asunto(s)
Hexosiltransferasas/metabolismo , Inflamación/enzimología , Isoenzimas/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Dominio Catalítico , Regulación Enzimológica de la Expresión Génica , Hexosiltransferasas/genética , Humanos , Isoenzimas/genética , Proteínas de la Membrana/genética , Polisacáridos/metabolismo
6.
BMC Genomics ; 18(1): 223, 2017 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-28274201

RESUMEN

BACKGROUND: Microalgal triglyceride (TAG) synthesis has attracted considerable attention. Particular emphasis has been put towards characterizing the algal homologs of the canonical rate-limiting enzymes, diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT). Less work has been done to analyze homologs from a phylogenetic perspective. In this work, we used HMMER iterative profiling and phylogenetic and functional analyses to determine the number and sequence characteristics of algal DGAT and PDAT, as well as related sequences that constitute their corresponding superfamilies. We included most algae with available genomes, as well as representative eukaryotic and prokaryotic species. RESULTS: Amongst our main findings, we identified a novel clade of DGAT1-like proteins exclusive to red algae and glaucophyta and a previously uncharacterized subclade of DGAT2 proteins with an unusual number of transmembrane segments. Our analysis also revealed the existence of a novel DGAT exclusive to green algae with moderate similarity to plant soluble DGAT3. The DGAT3 clade shares a most recent ancestor with a group of uncharacterized proteins from cyanobacteria. Subcellular targeting prediction suggests that most green algal DGAT3 proteins are imported to the chloroplast, evidencing that the green algal chloroplast might have a soluble pathway for the de novo synthesis of TAGs. Heterologous expression of C. reinhardtii DGAT3 produces an increase in the accumulation of TAG, as evidenced by thin layer chromatography. CONCLUSIONS: Our analysis contributes to advance in the knowledge of complex superfamilies involved in lipid metabolism and provides clues to possible enzymatic players of chloroplast TAG synthesis.


Asunto(s)
Chlorophyta/metabolismo , Cloroplastos/metabolismo , Diacilglicerol O-Acetiltransferasa/metabolismo , Redes y Vías Metabólicas , Triglicéridos/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Chlorophyta/clasificación , Chlorophyta/genética , Cloroplastos/genética , Biología Computacional/métodos , Simulación por Computador , Secuencia Conservada , Diacilglicerol O-Acetiltransferasa/química , Diacilglicerol O-Acetiltransferasa/genética , Evolución Molecular , Ferredoxinas/química , Ferredoxinas/genética , Ferredoxinas/metabolismo , Redes y Vías Metabólicas/ética , Filogenia , Posición Específica de Matrices de Puntuación , Triglicéridos/biosíntesis
8.
Molecules ; 20(5): 8357-94, 2015 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-26007170

RESUMEN

Unsaturated carbohydrate derivatives are useful intermediates in synthetic transformations leading to a variety of compounds. The aim of this review is to highlight the rich chemistry of ∆-2,3 unsaturated pyranosides, emphasizing the variety of transformations that have been carried out in these substrates during the last decade.


Asunto(s)
Carbohidratos/química , Monosacáridos/química , Reacción de Cicloadición , Glicosilación , Monosacáridos/síntesis química , Oxidación-Reducción
9.
Biochim Biophys Acta ; 1833(12): 3368-3374, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24140206

RESUMEN

UDP-Glucose:glycoprotein glucosyltransferase (UGGT) is a central component of the endoplasmic reticulum (ER) glycoprotein-folding quality control system, which prevents the exit of partially folded species. UGGT activity can be regulated by the accumulation of misfolded proteins in the ER, a stimulus that triggers a complex signaling pathway known as unfolded protein response (UPR) which is closely associated with inflammation and disease. In this work, we investigated the effect of progesterone (P4) on the expression and activity of UGGT in a mouse hybridoma. We detected the expression of two UGGT isoforms, UGGT1 and UGGT2, and demonstrated that both isoforms are active in these cells. Interestingly, the expression of each isoform is regulated by high physiological P4 concentrations. This work provides the first evidence of a hormonal regulation of UGGT isoform expression and activity, which might influence the glycoprotein quality control mechanism. These findings could contribute to the study of pathologies triggered by the accumulation of misfolded proteins.


Asunto(s)
Glicoproteínas/química , Glicoproteínas/metabolismo , Hexosiltransferasas/metabolismo , Progesterona/farmacología , Pliegue de Proteína , Animales , Silenciador del Gen/efectos de los fármacos , Glucosiltransferasas , Isoenzimas/metabolismo , Ratones , ARN Interferente Pequeño/metabolismo
10.
Chemistry ; 20(33): 10492-502, 2014 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-25043611

RESUMEN

Novel substrates that combine dicobalt hexacarbonyl propargyl (Nicholas) and pyranose-derived allylic (Ferrier) cations have been generated by treatment of hexacarbonyldicobalt (C-1)-alkynyl glycals with BF3 (.) Et2 O. The study of these cations has resulted in the discovery of novel reaction pathways that have shown to be associated to the nature of O-6 substituent in the starting alkynyl glycals. Accordingly, compounds resulting from ring expansion (oxepanes), ring contraction (tetrahydrofurans), or branched pyranoses, by incorporation of nucleophiles, can be obtained from 6-O-benzyl, 6-hydroxy, or 6-O-silyl derivatives, respectively. The use of a 6-O-allyl alkynyl glycal led to a suitable funtionalized oxepane able to experience an intramolecular Pauson-Khand cyclization leading to a single tricyclic derivative.

11.
J Biotechnol ; 380: 29-37, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38128617

RESUMEN

This work aimed to evaluate the effect of medium composition and volumetric oxygen transfer coefficient (kLa) on Y. lipolytica growth and production of microbial lipids and enzymes from hexadecane. In the stirred tank bioreactor, increasing kLa from 11 h-1 to 132 h-1 improved the hexadecane assimilation rate, biomass concentration, and lipids synthesis (0.90 g·L-1). A cost-effective hexadecane-based medium supplemented with corn steep liquor and a low amount of ammonium sulfate boosted lipids production up to 2.1 g·L-1, composed of palmitic, palmitoleic, oleic, and linoleic acids. The unsaturated/saturated fraction was dependent on the C/N ratio. Lipids of Y. lipolytica CBS 2075 are promising feedstock for animal feed, food additives, or the biodiesel industry. Simultaneous synthesis of extracellular lipase and protease from hexadecane was observed, which is a new feature that was not previously reported. The highest enzyme activity was obtained at the highest C/N ratio conditions. These results open new perspectives on the application of Y. lipolytica-based cultures for the biotransformation of hexadecane-polluted streams into valuable compounds, fulfilling an interesting strategy towards the circular economy concept.


Asunto(s)
Ácidos Grasos , Yarrowia , Animales , Ácidos Grasos/metabolismo , Yarrowia/metabolismo , Alcanos/metabolismo , Reactores Biológicos
12.
Respir Med ; 209: 107155, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36796547

RESUMEN

BACKGROUND: Hyperbaric oxygen therapy (HBOT) has been proposed to address COVID-19- associated respiratory failure. However, its biochemical effects are poorly known. METHOD: 50 patients with hypoxemic COVID-19 pneumonia were divided into C group (standard care) and H group (standard care plus HBOT). Blood was obtained at t = 0 and t = 5 days. Oxygen saturation (O2 Sat) was followed up. White blood cell (WC) count, lymphocytes (L) and platelets (P) and serum analysis (glucose, urea, creatinine, sodium, potassium, ferritin, D dimer, LDH and CRP) were carried out. Plasma levels of sVCAM, sICAM, sPselectin, SAA and MPO, and of cytokines (IL-1ß, IL-1RA, IL-6, TNFα, IFNα, IFNγ, IL-15, VEGF, MIP1α, IL-12p70, IL-2 and IP-10) were measured by multiplex assays. Angiotensin Converting Enzyme 2 (ACE-2) levels were determined by ELISA. RESULTS: The average basal O2 Sat was 85 ± 3%. The days needed to reach O2 Sat >90% were: H: 3 ± 1 and C: 5 ± 1 (P < 0,01). At term, H increased WC, L and P counts (all, H vs C: P < 0,01). Also, H diminished D dimer levels (H vs C, P < 0,001) and LDH concentration (H vs C, P < 0.01]. At term, H showed lower levels of sVCAM, sPselectin and SAA than C with respect to basal values (H vs C: ΔsVCAM: P < 0,01; ΔsPselectin: P < 0,05; ΔSAA: P < 0,01). Similarly, H showed diminished levels of TNFα (ΔTNFα: P < 0,05) and increased levels of IL-1RA and VEGF than C respect to basal values (H vs C: ΔIL-1RA and ΔVEGF: P < 0,05). CONCLUSION: Patients underwent HBOT improved O2 Sat with lower levels of severity markers (WC and platelets count, D dimer, LDH, SAA). Moreover, HBOT reduced proinflammatory agents (sVCAM, sPselectin, TNFα) and increased anti-inflammatory and pro-angiogenic ones (IL-1RA and VEGF).


Asunto(s)
COVID-19 , Oxigenoterapia Hiperbárica , Insuficiencia Respiratoria , Humanos , SARS-CoV-2 , COVID-19/complicaciones , COVID-19/terapia , Factor de Necrosis Tumoral alfa , Proteína Antagonista del Receptor de Interleucina 1 , Factor A de Crecimiento Endotelial Vascular , Insuficiencia Respiratoria/terapia
13.
Braz J Phys Ther ; 27(3): 100503, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37201307

RESUMEN

BACKGROUND: The Post-COVID-19 Functional Status (PCFS) scale was created to assess the functional status of patients after hospital discharge due to COVID-19. OBJECTIVE: To perform cross-cultural adaptation of the PCFS Scale and Manual into Brazilian Portuguese and evaluate its measurement properties in patients post-COVID-19. METHODS: For the cross-cultural adaptation, independent translations and back-translations were performed. This was followed by a pre-test, with analysis of the Content Validity Index (CVI), and preparation of the final version, after evaluating the measurement properties. Spearman's correlation between the PCFS and the WHO Disability Classification Scheme (WHODAS 2.0) was used for convergent validity. Weighted Kappa (wκ) was used for test-retest and interobserver reliability for PCFS scores and Kappa (κ) for PCFS items. Internal consistency was assessed using Cronbach's alpha. Only patients with post-discharge COVID-19 were evaluated through video-conferencing platforms. RESULTS: The CVI was 0.75-0.83 for comprehension and 0.83-0.84 for the language of the self-administered questionnaire and the structured interview version. For measurement properties, 63 patients were evaluated, 68% male, 51.50 (12.60) years, 12.28 (7.62) days of hospitalization. For the convergent validity, a strong correlation was found (r = 0.73; p<0.01). The test-retest (wκ=0.54) and interobserver (wκ=0.43) reliability was moderate and the item-by-item analyzes ranged from fair to substantial (κ=0.25-0.66) and weak to substantial (κ=0.07-0.79). Internal consistency was excellent (0.85). CONCLUSION: The final PCFS in Brazilian Portuguese showed adequate content validity, reliability, internal consistency, and convergent validity for the functional assessment of patients after hospital discharge due to COVID-19.


Asunto(s)
COVID-19 , Comparación Transcultural , Humanos , Masculino , Femenino , Brasil , Reproducibilidad de los Resultados , Cuidados Posteriores , Estado Funcional , Alta del Paciente , Encuestas y Cuestionarios , Traducciones , Psicometría
14.
J Hematol Oncol ; 16(1): 43, 2023 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-37120577

RESUMEN

Treatment-free remission (TFR) in chronic myeloid leukemia (CML) is safe under adequate molecular monitoring, but questions remain regarding which factors may be considered predictive for TFR. Argentina Stop Trial (AST) is a multicenter TFR trial showing that 65% of patients sustain molecular remission, and the prior time in deep molecular response (DMR) was associated with successful TFR. Luminex technology was used to characterize cytokines in plasma samples. Using machine learning algorithms, MCP-1 and IL-6 were identified as novel biomarkers and MCP-1low/IL-6low patients showed eightfold higher risk of relapse. These findings support the feasibility of TFR for patients in DMR and MCP-1/IL-6 plasma levels are strong predictive biomarkers.


Asunto(s)
Interleucina-6 , Leucemia Mielógena Crónica BCR-ABL Positiva , Humanos , Inhibidores de Proteínas Quinasas , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Biomarcadores , Inducción de Remisión , Resultado del Tratamiento
15.
Reprod Fertil Dev ; 24(8): 1123-33, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23043795

RESUMEN

It has been reported that fetal lymphoid progenitor cells are acquired during gestation and are able to develop in the maternal mouse thymus into functional T cells. Moreover, previous pregnancies increase the number of fetal cells in the mother. In the present study, we investigated whether mouse pregnancy induces changes in T lymphocyte subsets in the maternal thymus. We determined the T lymphocyte subsets in two allogeneic cross-breedings, namely CBA/J×BALB/c (normal) and CBA/J×DBA/2 (abortion prone), and investigated the effects of the age and parity of the female, as well as pregnancy outcome, on thymocyte populations. In addition, hormonal effects were evaluated in a syngeneic combination (CBA/J×CBA/J). We found that during pregnancy both hormonal and allogeneic stimuli induced a reduction in the CD4(+)CD8(+) subset with an increase in the CD4(+)CD8(-) population. Only young females of the normal combination exhibited an increase in the CD4(-)CD8(+) population. All young mice showed an increase in CD4(+)CD25(+)FoxP3(+) T cells. Interestingly, the γδT thymus pool was increased in all females of the normal allogeneic pregnancy only, suggesting the participation of this pool in the observed beneficial effect of multiparity in this cross-breeding. Our results demonstrate that allogeneic pregnancies induce important variations in maternal thymocyte subpopulations depending on the age of the female and the male component of the cross-breeding.


Asunto(s)
Hibridación Genética/inmunología , Ratones Endogámicos BALB C/inmunología , Ratones Endogámicos CBA/inmunología , Subgrupos de Linfocitos T , Timo/citología , Aborto Veterinario/genética , Envejecimiento , Animales , Femenino , Reabsorción del Feto/veterinaria , Edad Gestacional , Tamaño de la Camada , Ratones , Paridad , Embarazo
16.
J Biotechnol ; 331: 37-47, 2021 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-33652072

RESUMEN

Volatile fatty acids (VFAs), which can be generated by acidogenesis of organic wastes, are important building blocks for chemicals production, and are intermediates in many bioprocesses such as microbial lipids production. Important factors affecting the bioconversion of VFAs (acetate, propionate and butyrate) by Yarrowia lipolytica W29 and NCYC 2904 for growth and lipids accumulation were studied. Yarrowia lipolytica grew efficiently in VFAs-based media, but lipids production was enhanced by the addition of co-substrates (glucose or glycerol) in batch cultures. A two-stage batch culture - growth phase on glucose, followed by VFAs addition, improved lipids accumulation. Lipids concentrations of 2.3 g·L-1 and 3.5 g·L-1 were obtained with this mode of operation, with addition of 18 g·L-1 VFAs, for Y. lipolytica W29 and NCYC 2904, respectively. For the first time, it was demonstrated that oxygen mass transfer is a crucial factor for lipids production by Y. lipolytica from VFAs. Intracellular lipids produced by Y. lipolytica strains were mainly composed by oleic and linoleic acids, similar to common vegetable oils, making these lipids suitable for biodiesel production. Moreover, margaric acid, which may improve biodiesel properties, was only detected in propionate medium. The strategies studied herein will contribute to the feasibility of using VFAs as low-cost feedstock for microbial lipids production by Y. lipolytica strains.


Asunto(s)
Yarrowia , Biocombustibles , Ácidos Grasos , Ácidos Grasos Volátiles , Lípidos , Oxígeno
17.
Int J Diabetes Dev Ctries ; 41(4): 614-620, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35177883

RESUMEN

BACKGROUND: Heart rate-corrected QT (QTc) interval is associated with increased risk for cardiovascular events and mortality among individuals with diabetes mellitus (DM). Little is known about the epidemiology of prolonged QTc among people with DM in resource-limited settings. METHODS: We conducted a cross-sectional study among adults with diabetes in ambulatory care at the Mbarara Regional Referral Hospital, from November 2018 to April 2019. Twelve-lead ECG recordings were performed on all participants. We collected clinical and laboratory data related to diabetes disease status and treatment control. We estimated QTc using Bazett's formula and categorized it according to standardized sex-adjusted thresholds. Linear regression analysis was performed to identify correlates of QTc. RESULTS: We recruited 299 participants with a mean age of 50.1 years (SD±9.8) and mean HbA1c of 9.7 % (SD±2.6), and 69.6% were female. We detected prolonged and borderline QTc in 6.4% (19/299, 95% CI: 3.9-9.7%) and 23.4% (70/299, 95% CI: 18.7-28.6%) of participants, respectively. In multivariate models, factors associated with increasing QTc interval were mean arterial pressure (ß=0.34; 95% CI: 0.07-0.63, p=0.019) and female sex (ß=15.26; 95% CI: 7.58-22.94, p0.001). CONCLUSIONS: The prevalence of abnormal QTc among individuals in routine diabetes care in southwestern Uganda was high. Female sex and mean arterial pressure were correlated with QTc interval. Given these findings, future studies should explore the clinical impact of abnormal QTc in this patient population.

18.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(4): 181-188, 2021 Apr.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33279356

RESUMEN

OBJECTIVE: To determine and compare the diagnostic precision in glaucoma of two deep learning models using infrared images of the optic nerve, eye fundus, and the ganglion cell layer (GCL). METHODS: We have selected a sample of normal and glaucoma patients. Three infrared images were registered with a spectral-domain optical coherence tomography (SD-OCT). The first corresponds to the confocal scan image of the fundus, the second is a cut-out of the first centered on the optic nerve, and the third was the SD-OCT image of the GCL. Our deep learning models are developed on the MatLab platform with the ResNet50 and VGG19 pre-trained neural networks. RESULTS: 498 eyes of 298 patients were collected. Of the 498 eyes, 312 are glaucoma and 186 are normal. In the test, the precision of the models was 96% (ResNet50) and 96% (VGG19) for the GCL images, 90% (ResNet50) and 90% (VGG19) for the optic nerve images and 82% (ResNet50) and 84% (VGG19) for the fundus images. The ROC area in the test was 0.96 (ResNet50) and 0.97 (VGG19) for the GCL images, 0.87 (ResNet50) and 0.88 (VGG19) for the optic nerve images, and 0.79 (ResNet50) and 0.81 (VGG19) for the fundus images. CONCLUSIONS: Both deep learning models, applied to the GCL images, achieve high diagnostic precision, sensitivity and specificity in the diagnosis of glaucoma.

19.
Front Vet Sci ; 7: 219, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32411738

RESUMEN

Foot-and mouth disease (FMD) is an animal disease that generates many economic impacts and sanctions on the international market. In 2018, Brazil, the world's largest beef exporter, had the recognition by World Organization for Animal Health (OIE) as a country free of FMD with vaccination and proposed to withdraw FMD vaccination throughout the country, based on a 10-year schedule, beginning in 2019. Therefore, Brazil needs studies to help the decision-making process, particularly regarding the availability of resources for strengthening of official animal health services. The state of Mato Grosso do Sul (MS) was chosen to be analyzed for three reasons: the size of its herd, the economic importance of its livestock and its location-which lies on the border with Paraguay and Bolivia. The current study adopted the Social Network Analysis and performed an exploratory analysis of cattle movement in MS. The most central municipalities in the networks were identified and they can be seen as crucial in strategies to monitor animal movement and to control outbreaks. The cattle movement networks demonstrated to be strongly connected, implying a high-speed potential FMD diffusion, in case of reintroduction. In a second stage, we performed an exploratory analysis of animal movement within the state, assuming distinct points in time for the identification of animal origin. The results of the analysis underlined the need and relevance of investing in animal control, sanitary education for producers and equipment and technologies to assist in the early detection, diagnosis, and eradication of outbreaks in a fast and efficient manner, preventing a possible outbreak from spreading to other regions.

20.
Glob Heart ; 15(1): 21, 2020 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-32489794

RESUMEN

Background: Cardiovascular autonomic neuropathy (CAN) is a common complication in individuals with diabetes mellitus (DM) but often overlooked in clinical practice. The burden and correlates of CAN have not been extensively studied in low-income countries, particularly in sub-Saharan Africa. Objectives: To determine the prevalence and correlates of CAN among adults in ambulatory diabetes care in southwestern Uganda. Method: We conducted a cross-sectional study among adults with diabetes from November 2018 to April 2019. CAN was assessed using the five autonomic function tests: deep breathing, Valsalva maneuver, postural index on standing, change in blood pressure during standing and diastolic blood pressure response to isometric exercise. We estimated the prevalence of CAN and fit regression models to identify its demographic and clinical correlates. Results: We enrolled 299 individuals. The mean age was 50.1 years (SD ± 9.8), mean HbA1c was 9.7 (SD ± 2.6) and 69.6% were female. CAN was detected in 156/299 (52.2%) of the participants on the basis of one or more abnormal cardiovascular autonomic reflex tests. Out of 299 participants, 88 (29.4%) were classified as early CAN while 61/299 (20.4%) and 7/299 (2.3%) were classified as definite and severe (advanced) CAN respectively. In multivariable regression models, age over 50 years (aOR 3.48, 95%CI 1.35 -8.99, p = 0.010), duration of diabetes over 10 years (aOR 4.09, 95%CI 1.78 -9.38, p = 0.001), and presence of diabetic retinopathy (aOR 2.25, 95%CI 1.16 -4.34, p = 0.016) were correlated with CAN. Conclusions: Our findings reveal a high prevalence of CAN among individuals in routine outpatient care for diabetes mellitus in Uganda. Older age, longer duration of diabetes and coexistence of retinopathy are associated with CAN. Future work should explore the clinical significance and long term outcomes associated with CAN in this region.


Asunto(s)
Presión Sanguínea/fisiología , Enfermedades Cardiovasculares/fisiopatología , Diabetes Mellitus Tipo 2/epidemiología , Neuropatías Diabéticas/epidemiología , Hospitales/estadística & datos numéricos , Enfermedades Cardiovasculares/epidemiología , Comorbilidad , Estudios Transversales , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Uganda/epidemiología
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