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1.
Parasit Vectors ; 17(1): 232, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769548

RESUMEN

BACKGROUND: Schistosoma japonicum eggs lodge in the liver and induce a fibrotic granulomatous immune response in the liver of host. Galectin 3 (Gal-3) is a protein implicated in fibrosis in multiple organs. However, the pathology and molecular mechanisms promoting hepatic granuloma formation remain poorly understood. METHODS: To investigate the effect of blocking galectin-receptor interactions by α-lactose on liver immunopathology in mice with S. japonicum infection, C57BL/6 mice were infected with S. japonicum and alpha (α)-lactose was intraperitoneally injected to block the interactions of galectins and their receptors. RESULTS: Compared with S. japonicum-infected mice, there were significantly decreased Gal-3 mRNA and protein expression levels, decreased intensity of Gal-3 fluorescence in the liver, decreased serum ALT and AST levels, decreased egg numbers of S. japonicum in the liver section, attenuated hepatic and spleen pathology, and alleviated liver fibrosis accompanied with decreased protein expression levels of fibrosis markers [α-smooth muscle actin (α-SMA), collagen I, and collagen IV] in the liver of S. japonicum-infected mice blocked galectin-receptor interactions with hematoxylin-eosin staining, Masson's trichrome staining, immunohistochemistry, or Western blot analysis. Compared with S. japonicum-infected mice, blocking galectin-receptor interactions led to increased eosinophil infiltration and higher eosinophil cationic protein (ECP) expression in the liver, accompanied by increased mRNA levels of eosinophil granule proteins [ECP and eosinophil peroxidase (EPO)], IL-5, CCL11, and CCR3 in the liver and decreased mRNA levels of Gal-3 and M2 macrophage cytokines (TGF-ß, IL-10, and IL-4) in the liver and spleen by using quantitative real-time reverse transcription-polymerase chain reaction. In addition, there were increased Beclin1 protein expression and protein expression ratio of LC3B-II/LC3B-I and decreased p62 protein expression and protein expression ratios of phospho-mTOR/mTOR and phospho-AKT/AKT by Western blot; increased double-labeled F4/80+/LC3B+ cells by immunofluorescence staining; increased M1 macrophage polarization in the liver of S. japonicum-infected mice blocked galectin-receptor interactions by flow cytometric analysis and immunofluorescence staining. CONCLUSIONS: Our data found that blockage of galectin-receptor interactions downregulated Gal-3, which in turn led to reduced liver functional damage, elevated liver eosinophil recruitment, promoted macrophage autophagy through the Akt/mTOR signaling pathway, and alleviated liver pathology and fibrosis. Therefore, Gal-3 plays a pivotal role during S. japonicum infection and could be a target of pharmacologic potential for liver fibrosis induced by S. japonicum infection.


Asunto(s)
Galectina 3 , Cirrosis Hepática , Ratones Endogámicos C57BL , Schistosoma japonicum , Esquistosomiasis Japónica , Animales , Esquistosomiasis Japónica/parasitología , Esquistosomiasis Japónica/complicaciones , Cirrosis Hepática/parasitología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Ratones , Galectina 3/metabolismo , Galectina 3/genética , Hígado/parasitología , Hígado/patología , Hígado/metabolismo , Femenino , Lactosa/farmacología , Lactosa/análogos & derivados , Galectinas/metabolismo , Galectinas/genética
2.
PLoS One ; 19(5): e0303872, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38771780

RESUMEN

BACKGROUND: Antimicrobial resistance (AMR) is among the top public health concerns in the globe. Estimating the prevalence of multidrug resistance (MDR), MDR index (MDR-I) and extended-spectrum beta-lactamase (ESBL)-producing lactose fermenting Enterobacteriaceae (LFE) is important in designing strategies to combat AMR. Thus, this study was designed to determine the status of MDR, MDR-I and ESBL-producing LFE isolated from the human-dairy interface in the northwestern part of Ethiopia, where such information is lacking. METHODOLOGY: A cross-sectional study was conducted from June 2022 to August 2023 by analyzing 362 samples consisting of raw pooled milk (58), milk container swabs (58), milker's hand swabs (58), farm sewage (57), milker's stool (47), and cow's feces (84). The samples were analyzed using standard bacteriological methods. The antimicrobial susceptibility patterns and ESBL production ability of the LFE isolates were screened using the Kirby-Bauer disk diffusion method, and candidate isolates passing the screening criteria were phenotypically confirmed by using cefotaxime (30 µg) and cefotaxime /clavulanic acid (30 µg/10 µg) combined-disk diffusion test. The isolates were further characterized genotypically using multiplex polymerase chain reaction targeting the three ESBL-encoding- genes namely blaTEM, blaSHV, and blaCTX-M. RESULTS: A total of 375 bacterial isolates were identified and the proportion of MDR and ESBL-producing bacterial isolates were 70.7 and 21.3%, respectively. The MDR-I varied from 0.0 to 0.81 with an average of 0.30. The ESBL production was detected in all sample types. Genotypically, the majority of the isolates (97.5%), which were positive on the phenotypic test, were carrying one or more of the three genes. CONCLUSION: A high proportion of the bacterial isolates were MDR; had high MDR-I and were positive for ESBL production. The findings provide evidence that the human-dairy interface is one of the important reservoirs of AMR traits. Therefore, the implementation of AMR mitigation strategies is highly needed in the area.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Enterobacteriaceae , Lactosa , beta-Lactamasas , Humanos , Etiopía , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Enterobacteriaceae/genética , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Enterobacteriaceae/enzimología , Lactosa/metabolismo , Farmacorresistencia Bacteriana Múltiple/genética , Estudios Transversales , Antibacterianos/farmacología , Animales , Pruebas de Sensibilidad Microbiana , Bovinos , Infecciones por Enterobacteriaceae/microbiología , Cefotaxima/farmacología , Leche/microbiología , Fermentación , Heces/microbiología
3.
Appl Microbiol Biotechnol ; 108(1): 338, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771321

RESUMEN

Fucosyl-oligosaccharides (FUS) provide many health benefits to breastfed infants, but they are almost completely absent from bovine milk, which is the basis of infant formula. Therefore, there is a growing interest in the development of enzymatic transfucosylation strategies for the production of FUS. In this work, the α-L-fucosidases Fuc2358 and Fuc5372, previously isolated from the intestinal bacterial metagenome of breastfed infants, were used to synthesize fucosyllactose (FL) by transfucosylation reactions using p-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) as donor and lactose as acceptor. Fuc2358 efficiently synthesized the major fucosylated human milk oligosaccharide (HMO) 2'-fucosyllactose (2'FL) with a 35% yield. Fuc2358 also produced the non-HMO FL isomer 3'-fucosyllactose (3'FL) and traces of non-reducing 1-fucosyllactose (1FL). Fuc5372 showed a lower transfucosylation activity compared to Fuc2358, producing several FL isomers, including 2'FL, 3'FL, and 1FL, with a higher proportion of 3'FL. Site-directed mutagenesis using rational design was performed to increase FUS yields in both α-L-fucosidases, based on structural models and sequence identity analysis. Mutants Fuc2358-F184H, Fuc2358-K286R, and Fuc5372-R230K showed a significantly higher ratio between 2'FL yields and hydrolyzed pNP-Fuc than their respective wild-type enzymes after 4 h of transfucosylation. The results with the Fuc2358-F184W and Fuc5372-W151F mutants showed that the residues F184 of Fuc2358 and W151 of Fuc5372 could have an effect on transfucosylation regioselectivity. Interestingly, phenylalanine increases the selectivity for α-1,2 linkages and tryptophan for α-1,3 linkages. These results give insight into the functionality of the active site amino acids in the transfucosylation activity of the GH29 α-L-fucosidases Fuc2358 and Fuc5372. KEY POINTS: Two α-L-fucosidases from infant gut bacterial microbiomes can fucosylate glycans Transfucosylation efficacy improved by tailored point-mutations in the active site F184 of Fuc2358 and W151 of Fuc5372 seem to steer transglycosylation regioselectivity.


Asunto(s)
Microbioma Gastrointestinal , Metagenoma , Leche Humana , Trisacáridos , alfa-L-Fucosidasa , alfa-L-Fucosidasa/genética , alfa-L-Fucosidasa/metabolismo , Humanos , Trisacáridos/metabolismo , Leche Humana/química , Lactosa/metabolismo , Oligosacáridos/metabolismo , Mutagénesis Sitio-Dirigida , Lactante , Fucosa/metabolismo
4.
Bioorg Chem ; 147: 107395, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38705105

RESUMEN

Fluorination of carbohydrate ligands of lectins is a useful approach to examine their binding profile, improve their metabolic stability and lipophilicity, and convert them into 19F NMR-active probes. However, monofluorination of monovalent carbohydrate ligands often leads to a decreased or completely lost affinity. By chemical glycosylation, we synthesized the full series of methyl ß-glycosides of N,N'-diacetylchitobiose (GlcNAcß(1-4)GlcNAcß1-OMe) and LacdiNAc (GalNAcß(1-4)GlcNAcß1-OMe) systematically monofluorinated at all hydroxyl positions. A competitive enzyme-linked lectin assay revealed that the fluorination at the 6'-position of chitobioside resulted in an unprecedented increase in affinity to wheat germ agglutinin (WGA) by one order of magnitude. For the first time, we have characterized the binding profile of a previously underexplored WGA ligand LacdiNAc. Surprisingly, 4'-fluoro-LacdiNAc bound WGA even stronger than unmodified LacdiNAc. These observations were interpreted using molecular dynamic calculations along with STD and transferred NOESY NMR techniques, which gave evidence for the strengthening of CH/π interactions after deoxyfluorination of the side chain of the non-reducing GlcNAc. These results highlight the potential of fluorinated glycomimetics as high-affinity ligands of lectins and 19F NMR-active probes.


Asunto(s)
Disacáridos , Aglutininas del Germen de Trigo , Disacáridos/química , Disacáridos/síntesis química , Aglutininas del Germen de Trigo/química , Aglutininas del Germen de Trigo/metabolismo , Halogenación , Estructura Molecular , Acetilglucosamina/química , Acetilglucosamina/metabolismo , Lactosa/análogos & derivados
5.
Food Res Int ; 183: 114175, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38760120

RESUMEN

Lactose hydrolysed concentrated milk was prepared using ß-galactosidase enzyme (4.76U/mL) with a reaction period of 12 h at 4 °C. Addition of polysaccharides (5 % maltodextrin/ß-cyclodextrin) to concentrated milk either before or after lactose hydrolysis did not result in significant differences (p > 0.05) in degree of hydrolysis (% DH) of lactose and residual lactose content (%). Three different inlet temperatures (165 °C, 175 °C and 185 °C) were used for the preparation of powders which were later characterised based on physico-chemical and maillard browning characteristics. Moisture content, solubility and available lysine content of the powders decreased significantly, whereas, browning parameters i.e., browning index, 5-hydroxymethylfurfural, furosine content increased significantly (p < 0.05) with an increase in inlet air temperature. The powder was finally prepared with 5 % polysaccharide and an inlet air temperature of 185 °C which reduced maillard browning. Protein-polysaccharide interactions were identified using Fourier Transform infrared spectroscopy, fluorescence spectroscopy and determination of free amino groups in the powder samples. Maltodextrin and ß-cyclodextrin containing powder samples exhibited lower free amino groups and higher degree of graft value as compared to control sample which indicated protein-polysaccharide interactions. Results obtained from Fourier Transform infrared spectroscopy also confirmed strong protein-polysaccharide interactions, moreover a significant decrease in fluorescence intensity was also observed in the powder samples. These interactions between the proteins and polysaccharides reduced the maillard browning in powders.


Asunto(s)
Furaldehído , Lactosa , Reacción de Maillard , Leche , Polisacáridos , Polvos , Lactosa/química , Polisacáridos/química , Leche/química , Animales , Espectroscopía Infrarroja por Transformada de Fourier , Furaldehído/análogos & derivados , Furaldehído/química , beta-Galactosidasa/metabolismo , beta-Ciclodextrinas/química , Hidrólisis , Secado por Pulverización , Temperatura , Lisina/química , Lisina/análogos & derivados , Solubilidad , Espectrometría de Fluorescencia , Proteínas de la Leche/química , Manipulación de Alimentos/métodos
6.
Cryo Letters ; 45(2): 134-138, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38557992

RESUMEN

BACKGROUND: Examining semen cryopreservation in Calomys laucha offers valuable insights for reproductive research and species conservation. OBJECTIVE: To determine the most effective sugar for the cryopreservation of C. laucha semen. MATERIALS AND METHODS: Using 36 epididymides from C. laucha, semen samples were diluted in a 3% skimmed milk medium supplemented with one of four sugars (glucose, fructose, lactose, or sucrose) at a concentration of 0.3 M. These mixtures underwent a conditioning phase at 37 degree C for 10 min, cooled to -80 degree C for another 10 min, and were subsequently stored in liquid nitrogen. RESULTS: Upon thawing, samples treated with lactose and glucose solutions show superior sperm motility, achieving 8.2% and 10.0% respectively, in contrast to the fructose (2.0%) and sucrose (4.1%) mixtures. Furthermore, samples preserved in glucose registered the highest sperm penetration rates, reaching 44.9%. CONCLUSION: Our findings suggest that a cryopreservation medium containing 0.3 M glucose can contribute to the safeguarding C. laucha rodent semen. https://doi.org/10.54680/fr24210110612.


Asunto(s)
Preservación de Semen , Semen , Animales , Masculino , Criopreservación , Lactosa , Roedores , Motilidad Espermática , Glucosa/farmacología , Fructosa , Sacarosa/farmacología , Espermatozoides , Crioprotectores
7.
Food Microbiol ; 121: 104487, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38637064

RESUMEN

Streptococcus thermophilus is a bacterium widely used in the production of yogurts and cheeses, where it efficiently ferments lactose, the saccharide naturally present in milk. It is also employed as a starter in dairy- or plant-based fermented foods that contain saccharides other than lactose (e.g., sucrose, glucose). However, little is known about how saccharide use is regulated, in particular when saccharides are mixed. Here, we determine the effect of the 5 sugars that S. thermophilus is able to use, at different concentration and when they are mixed on the promoter activities of the C-metabolism genes. Using a transcriptional fusion approach, we discovered that lactose and glucose modulated the activity of the lacS and scrA promoters in a concentration-dependent manner. When mixed with lactose, glucose also repressed the two promoter activities; when mixed with sucrose, lactose still repressed scrA promoter activity. We determined that catabolite control protein A (CcpA) played a key role in these dynamics. We also showed that promoter activity was linked with glycolytic flux, which varied depending on saccharide type and concentration. Overall, this study identified key mechanisms in carbohydrate metabolism - autoregulation and partial hierarchical control - and demonstrated that they are partly mediated by CcpA.


Asunto(s)
Glucosa , Lactosa , Lactosa/metabolismo , Glucosa/metabolismo , Metabolismo de los Hidratos de Carbono , Glucólisis , Streptococcus thermophilus/genética , Streptococcus thermophilus/metabolismo , Sacarosa/metabolismo
8.
Bioprocess Biosyst Eng ; 47(6): 919-929, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38644439

RESUMEN

The growing need in the current market for innovative solutions to obtain lactose-free (L-F) milk is caused by the annual increase in the prevalence of lactose intolerance inside as well as the newborn, children, and adults. Various configurations of enzymes can yield two distinct L-F products: sweet (ß-galactosidase) and unsweet (ß-galactosidase and glucose oxidase) L-F milk. In addition, the reduction of sweetness through glucose decomposition should be performed in a one-pot mode with catalase to eliminate product inhibition caused by H2O2. Both L-F products enjoy popularity among a rapidly expanding group of consumers. Although enzyme immobilization techniques are well known in industrial processes, new carriers and economic strategies are still being searched. Polymeric carriers, due to the variety of functional groups and non-toxicity, are attractive propositions for individual and co-immobilization of food enzymes. In the presented work, two strategies (with free and immobilized enzymes; ß-galactosidase NOLA, glucose oxidase from Aspergillus niger, and catalase from Serratia sp.) for obtaining sweet and unsweet L-F milk under low-temperature conditions were proposed. For free enzymes, achieving the critical assumption, lactose hydrolysis and glucose decomposition occurred after 1 and 4.3 h, respectively. The tested catalytic membranes were created on regenerated cellulose and polyamide. In both cases, the time required for lactose and glucose bioconversion was extended compared to free enzymes. However, these preparations could be reused for up to five (ß-galactosidase) and ten cycles (glucose oxidase with catalase).


Asunto(s)
Enzimas Inmovilizadas , Glucosa Oxidasa , Lactosa , Leche , beta-Galactosidasa , beta-Galactosidasa/metabolismo , beta-Galactosidasa/química , Leche/química , Lactosa/metabolismo , Lactosa/química , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Animales , Aspergillus niger/enzimología , Glucosa/metabolismo , Glucosa/química , Catalasa/metabolismo , Catalasa/química , Membranas Artificiales
9.
Front Endocrinol (Lausanne) ; 15: 1386510, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38665263

RESUMEN

In hypothyroid patients needing large doses of levothyroxine (L-T4) (>1.7-2 µg/kg/day) to reach euthyroidism, lactose intolerance (LI) needs to be excluded, owing to the high prevalence in the population. If LI is present, a lactose-free diet decreases the rate of L-T4 malabsorption. However, an increased requirement of L-T4 is described in patients with LI, which can be beneficially treated using lactose-free L-T4 formulation. The lactose-free liquid L-T4 formulation is able to circumvent LI malabsorption leading to the normalization of thyroid-stimulating hormone (TSH) in patients with subclinical hypothyroidism and long-term stable TSH levels.


Asunto(s)
Hipotiroidismo , Intolerancia a la Lactosa , Tiroxina , Humanos , Intolerancia a la Lactosa/tratamiento farmacológico , Tiroxina/uso terapéutico , Tiroxina/farmacocinética , Hipotiroidismo/tratamiento farmacológico , Hipotiroidismo/metabolismo , Lactosa , Femenino , Síndromes de Malabsorción/tratamiento farmacológico , Síndromes de Malabsorción/metabolismo , Masculino , Persona de Mediana Edad , Tirotropina/sangre , Tirotropina/metabolismo , Adulto
10.
Nutrients ; 16(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613035

RESUMEN

Lactose intolerance, which affects about 65-75% of the world's population, is caused by a genetic post-weaning deficiency of lactase, the enzyme required to digest the milk sugar lactose, called lactase non-persistence. Symptoms of lactose intolerance include abdominal pain, bloating and diarrhea. Genetic variations, namely lactase persistence, allow some individuals to metabolize lactose effectively post-weaning, a trait thought to be an evolutionary adaptation to dairy consumption. Although lactase non-persistence cannot be altered by diet, prebiotic strategies, including the consumption of galactooligosaccharides (GOSs) and possibly low levels of lactose itself, may shift the microbiome and mitigate symptoms of lactose consumption. This review discusses the etiology of lactose intolerance and the efficacy of prebiotic approaches like GOSs and low-dose lactose in symptom management.


Asunto(s)
Intolerancia a la Lactosa , Humanos , Intolerancia a la Lactosa/genética , Lactosa , Lactasa/genética , Dolor Abdominal , Evolución Biológica , Prebióticos
11.
Arch Pharm Res ; 47(4): 325-340, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38561494

RESUMEN

Sialyllactoses (SLs) primarily include sialylated human milk oligosaccharides (HMOs) and bovine milk oligosaccharides (BMOs). First, the safety assessment of 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL) revealed low toxicity in various animal models and human participants. SLs constitute a unique milk component, highlighting the essential nutrients and bioactive components crucial for infant development, along with numerous associated health benefits for various diseases. This review explores the safety, biosynthesis, and potential biological effects of SLs, with a specific focus on their influence across various physiological systems, including the gastrointestinal system, immune disorders, rare genetic disorders (such as GNE myopathy), cancers, neurological disorders, cardiovascular diseases, diverse cancers, and viral infections, thus indicating their therapeutic potential.


Asunto(s)
Lactosa/análogos & derivados , Leche Humana , Leche , Oligosacáridos , Humanos , Oligosacáridos/química , Oligosacáridos/metabolismo , Animales , Leche/química , Leche Humana/química , Leche Humana/metabolismo , Bovinos
12.
Biomater Adv ; 160: 213849, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599041

RESUMEN

Spheroids derived from human mesenchymal stem cells (hMSCs) are of limited use for cartilage regeneration, as the viability of the cells progressively decreases during the period required for chondrogenic differentiation (21 days). In this work, spheroids based on hMSCs and a lactose-modified chitosan (CTL) were formed by seeding cells onto an air-dried coating of CTL. The polymer coating can inhibit cell adhesion and it is simultaneously incorporated into spheroid structure. CTL-spheroids were characterized from a morphological and biological perspective, and their properties were compared with those of spheroids obtained by seeding the cells onto a non-adherent surface (agar gel). Compared to the latter, smaller and more viable spheroids form in the presence of CTL as early as 4 days of culture. At this time point, analysis of stem cells differentiation in spheroids showed a remarkable increase in collagen type-2 (COL2A1) gene expression (~700-fold compared to day 0), whereas only a 2-fold increase was observed in the control spheroids at day 21. These results were confirmed by histological and transmission electron microscopy (TEM) analyses, which showed that in CTL-spheroids an early deposition of collagen with a banding structure already occurred at day 7. Overall, these results support the use of CTL-spheroids as a novel system for cartilage regeneration, characterized by increased cell viability and differentiation capacity within a short time-frame. This will pave the way for approaches aimed at increasing the success rate of procedures and reducing the time required for tissue regeneration.


Asunto(s)
Diferenciación Celular , Quitosano , Condrogénesis , Lactosa , Células Madre Mesenquimatosas , Esferoides Celulares , Quitosano/farmacología , Quitosano/química , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Humanos , Diferenciación Celular/efectos de los fármacos , Condrogénesis/efectos de los fármacos , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/citología , Lactosa/farmacología , Lactosa/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colágeno Tipo II/metabolismo , Colágeno Tipo II/genética
13.
Sci Rep ; 14(1): 7852, 2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570624

RESUMEN

CsqR (YihW) is a local transcription factor that controls expression of yih genes involved in degradation of sulfoquinovose in Escherichia coli. We recently showed that expression of the respective gene cassette might be regulated by lactose. Here, we explore the phylogenetic and functional traits of CsqR. Phylogenetic analysis revealed that CsqR had a conserved Met25. Western blot demonstrated that CsqR was synthesized in the bacterial cell as two protein forms, 28.5 (CsqR-l) and 26 kDa (CsqR-s), the latter corresponding to start of translation at Met25. CsqR-s was dramatically activated during growth with sulfoquinovose as a sole carbon source, and displaced CsqR-l in the stationary phase during growth on rich medium. Molecular dynamic simulations revealed two possible states of the CsqR-s structure, with the interdomain linker being represented by either a disordered loop or an ɑ-helix. This helix allowed the hinge-like motion of the N-terminal domain resulting in a switch of CsqR-s between two conformational states, "open" and "compact". We then modeled the interaction of both CsqR forms with putative effectors sulfoquinovose, sulforhamnose, sulfoquinovosyl glycerol, and lactose, and revealed that they all preferred the same pocket in CsqR-l, while in CsqR-s there were two possible options dependent on the linker structure.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Filogenia , Lactosa/metabolismo , Proteínas de Escherichia coli/metabolismo
14.
Microb Cell Fact ; 23(1): 112, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622596

RESUMEN

BACKGROUND: Filamentous fungi have long been recognized for their exceptional enzyme production capabilities. Among these, Trichoderma reesei has emerged as a key producer of various industrially relevant enzymes and is particularly known for the production of cellulases. Despite the availability of advanced gene editing techniques for T. reesei, the cultivation and characterization of resulting strain libraries remain challenging, necessitating well-defined and controlled conditions with higher throughput. Small-scale cultivation devices are popular for screening bacterial strain libraries. However, their current use for filamentous fungi is limited due to their complex morphology. RESULTS: This study addresses this research gap through the development of a batch cultivation protocol using a microbioreactor for cellulase-producing T. reesei strains (wild type, RutC30 and RutC30 TR3158) with offline cellulase activity analysis. Additionally, the feasibility of a microscale fed-batch cultivation workflow is explored, crucial for mimicking industrial cellulase production conditions. A batch cultivation protocol was developed and validated using the BioLector microbioreactor, a Round Well Plate, adapted medium and a shaking frequency of 1000 rpm. A strong correlation between scattered light intensity and cell dry weight underscores the reliability of this method in reflecting fungal biomass formation, even in the context of complex fungal morphology. Building on the batch results, a fed-batch strategy was established for T. reesei RutC30. Starting with a glucose concentration of 2.5 g l - 1 in the batch phase, we introduced a dual-purpose lactose feed to induce cellulase production and prevent carbon catabolite repression. Investigating lactose feeding rates from 0.3 to 0.75 g (l h) - 1 , the lowest rate of 0.3 g (l h) - 1 revealed a threefold increase in cellobiohydrolase and a fivefold increase in ß -glucosidase activity compared to batch processes using the same type and amount of carbon sources. CONCLUSION: We successfully established a robust microbioreactor batch cultivation protocol for T. reesei wild type, RutC30 and RutC30 TR3158, overcoming challenges associated with complex fungal morphologies. The study highlights the effectiveness of microbioreactor workflows in optimizing cellulase production with T. reesei, providing a valuable tool for simultaneous assessment of critical bioprocess parameters and facilitating efficient strain screening. The findings underscore the potential of microscale fed-batch strategies for enhancing enzyme production capabilities, revealing insights for future industrial applications in biotechnology.


Asunto(s)
Celulasa , Hypocreales , Trichoderma , Celulasa/metabolismo , Lactosa/metabolismo , Reproducibilidad de los Resultados , Biotecnología , Trichoderma/metabolismo
15.
Int J Pharm ; 656: 124116, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38615803

RESUMEN

Inhalation of pharmaceutical aerosol formulations is widely used to treat respiratory diseases. Spatially resolved thermal characterization offers promise for better understanding drug release rates from particles; however, this has been an analytical challenge due to the small particle size (from a few micrometers down to nanometers) and the complex composition of the formulations. Here, we employ nano-thermal analysis (nanoTA) to probe the nanothermal domain of a pharmaceutical aerosol formulation containing a mixture of fluticasone propionate (FP), salmeterol xinafoate (SX), and excipient lactose, which is widely used to treat asthma and chronic obstructive pulmonary disease (COPD). Furthermore, atomic force microscopy-infrared spectroscopy (AFM-IR) and AFM force measurements are performed to provide nanochemical and nanomechanical information to complement the nanothermal data. The colocalized thermal and chemical mapping clearly reveals the surface heterogeneity of the drugs in the aerosol particles and demonstrates the contribution of the surface chemical composition to the variation in the thermal properties of the particles. We present a powerful analytical approach for in-depth characterization of thermal/chemical/morphological properties of dry powder inhaler particles at micro- and nanometer scales. This approach can be used to facilitate the comparison between generics and reference inhalation products and further the development of high-performance pharmaceutical formulations.


Asunto(s)
Aerosoles , Inhaladores de Polvo Seco , Fluticasona , Lactosa , Microscopía de Fuerza Atómica , Tamaño de la Partícula , Polvos , Xinafoato de Salmeterol , Fluticasona/química , Fluticasona/administración & dosificación , Xinafoato de Salmeterol/química , Xinafoato de Salmeterol/administración & dosificación , Lactosa/química , Microscopía de Fuerza Atómica/métodos , Excipientes/química , Administración por Inhalación , Broncodilatadores/administración & dosificación , Broncodilatadores/química , Espectrofotometría Infrarroja/métodos , Química Farmacéutica/métodos , Propiedades de Superficie
16.
Int J Biol Macromol ; 264(Pt 1): 130600, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38442829

RESUMEN

We explored the rheological and tribological properties of potato starch agglomerated with a sugar binder (maltodextrin or lactose) at various concentrations by using a fluidized bed granulator. The magnitudes of consistency index and apparent viscosity of agglomerated potato starch (APS) decreased as the binder concentration was increased. Moreover, APS with a sugar binder showed lower viscoelastic moduli and higher tan δ values compared to APS with water as the binder (the control). The gel strength of all agglomerates decreased as the sugar concentration was increased. All samples showed anti-thixotropic behavior, and especially, APS with 20 % lactose showed a small anti-thixotropic area. Utilizing the Arrhenius equation clearly elucidated the effect of temperature on the apparent viscosity of all the samples. Although the maltodextrin concentration had little influence on the activation energy of APS, it increased as the lactose concentration was increased. APS samples with a sugar binder showed greater friction coefficient values compared to the control, with maltodextrin having a significant impact. The findings indicate that the rheological and tribological properties of APS rely on the type and concentration of sugar binder.


Asunto(s)
Solanum tuberosum , Lactosa , Almidón , Azúcares , Temperatura , Reología , Viscosidad
17.
Int J Pharm ; 655: 123966, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38452834

RESUMEN

The potential of fine excipient materials to improve the aerodynamic performance of carrier-based dry powder inhalation (DPI) formulations is well acknowledged but not fully elucidated. To improve the understanding of this potential, we studied two fine excipient materials: micronized lactose particles and silica microspheres. Inhalation formulations, each composed of a coarse lactose carrier, one of the two fine excipient materials (0.0-15.0 % w/w), and a spray-dried drug (fluticasone propionate) material (1.5 % w/w) were prepared. The physical structure, the flow behavior, the aerosolization behavior, and the aerodynamic performance of the formulations were studied. The two fine excipient materials similarly occupied carrier surface macropores. However, only the micronized lactose particles formed agglomerates and appeared to increase the tensile strength of the formulations. At 2.5 % w/w, the two fine excipient materials similarly improved drug dispersibility, whereas at higher concentrations, the micronized lactose material was more beneficial than the silica microspheres. The findings suggest that fine excipient materials improve drug dispersibility from carrier-based DPI formulations at low concentrations by filling carrier surface macropores and at high concentrations by forming agglomerates and/or enforcing fluidization. The study emphasizes critical attributes of fine excipient materials in carrier-based DPI formulations.


Asunto(s)
Excipientes , Lactosa , Excipientes/química , Polvos/química , Lactosa/química , Portadores de Fármacos/química , Inhaladores de Polvo Seco , Administración por Inhalación , Propiedades de Superficie , Dióxido de Silicio , Tamaño de la Partícula , Aerosoles/química
18.
Transplant Cell Ther ; 30(5): 548.e1-548.e4, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460728

RESUMEN

The rise of Vancomycin-resistant enterococci (VRE) strains among cellular therapy recipients raises concerns due to increased morbidity, mortality, and hospitalization costs, particularly impacting transplanted patients with diminished survival expectations. Recent research linking lactose to Enterococcus growth and graft-versus-host disease (GVHD) emphasizes the need for data on reducing lactose in the diets of VRE-carrying patients, especially in cellular therapy contexts like CAR-T or allogeneic hematopoietic stem cell transplantation. Responding to elevated VRE positivity rates in rectal swabs among patients in our BMT Unit, a unique nutritional strategy was implemented, introducing lactose-free milk and strictly enforcing lactose-free diets. This approach resulted in a significant reduction in VRE carriers, with a 16% positivity rate in the Lactose Group versus 3.6% in the Lactose-Free Group, as of June 2023. These results indicate the potential efficacy of this innovative nutritional strategy in high-risk departments, such as BMT Units and Intensive Care Units, with implications for reducing isolation strategies and inappropriate antibiotic use in cases of VRE colonization.


Asunto(s)
Enterococos Resistentes a la Vancomicina , Humanos , Lactosa , Infecciones por Bacterias Grampositivas/prevención & control , Masculino , Femenino , Leche/microbiología , Trasplante de Médula Ósea
19.
Int J Pharm ; 656: 124059, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38552753

RESUMEN

Most of biopharmaceuticals, in their liquid form, are prone to instabilities during storage. In order to improve their stability, lyophilization is the most commonly used drying technique in the pharmaceutical industry. In addition, certain applications of biopharmaceutical products can be considered by oral administration and tablets are the most frequent solid pharmaceutical dosage form used for oral route. Thus, the tableting properties of freeze-dried products used as cryo and lyoprotectant could be a key element for future pharmaceutical developments and applications. In this study, we investigated the properties that might play a particular role in the specific compaction behavior of freeze-dried excipients. The tableting properties of freeze-dried trehalose, lactose and mannitol were investigated and compared to other forms of these excipients (spray-dried, commercial crystalline and commercial crystalline milled powders). The obtained results showed a specific behavior in terms of compressibility, tabletability and brittleness for the amorphous powders obtained after freeze-drying. The comparison with the other powders showed that this specific tableting behavior is linked to both the specific texture and the physical state (amorphization) of these freeze-dried powders.


Asunto(s)
Composición de Medicamentos , Excipientes , Liofilización , Lactosa , Manitol , Polvos , Comprimidos , Trehalosa , Excipientes/química , Manitol/química , Composición de Medicamentos/métodos , Trehalosa/química , Lactosa/química , Polvos/química , Secado por Pulverización , Química Farmacéutica/métodos
20.
Anim Reprod Sci ; 264: 107455, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547816

RESUMEN

Boar sperm is highly susceptible to cold damage. When temperature drops to 5°C, the plasmatic membrane is destabilized. The freezing process causes a reduction of the fertility window because frozen/thawed boar sperm has less survivability. The aim of this work was to analyze the effect on sperm characteristics and response to capacitation stimuli of cooling to 5°C using a controlled protocol. Also, we evaluated if the addition of Glycerol 2% or 3% at 5°C was able to modify these parameters. For this purpose, we assessed motility, plasmatic membrane integrity and acrosomal membrane status. Capacitation was induced using Tyrode´s capacitating medium (TCM) and assessed by chlortetracycline stain and induction of acrosomal reaction with Progesterone. Motility patterns were analyzed using a CASA system. These tests were performed at three different points of the freezing curve: 37°C; 17°C and 5°C. Response to TCM vs TBM was only significant at 37°C. While at 37°C and 17°C capacitated sperm was below 20%, at 5°C reached 50% both in the TBM and TCM. CASA analysis showed that spermatozoa exposed to TCM had higher LIN and WOB than those in TBM. All parameters were similar in the Glycerol concentrations studied. These results suggest that the chilling process may be causing an effect similar to cryocapacitation along the cooling curve, starting subtle at 17°C and reaching 50% of the sperm population at 5°C, being independent of Glycerol concentration.


Asunto(s)
Frío , Criopreservación , Crioprotectores , Yema de Huevo , Glicerol , Preservación de Semen , Espermatozoides , Animales , Masculino , Glicerol/farmacología , Porcinos , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiología , Crioprotectores/farmacología , Yema de Huevo/química , Criopreservación/veterinaria , Criopreservación/métodos , Lactosa/farmacología , Motilidad Espermática/efectos de los fármacos
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