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BACKGROUND: Small airways disease (SAD) is a major cause of airflow obstruction in COPD patients and has been identified as a precursor to emphysema. Although the amount of SAD in the lungs can be quantified using our Parametric Response Mapping (PRM) approach, the full breadth of this readout as a measure of emphysema and COPD progression has yet to be explored. We evaluated topological features of PRM-derived normal parenchyma and SAD as surrogates of emphysema and predictors of spirometric decline. METHODS: PRM metrics of normal lung (PRMNorm) and functional SAD (PRMfSAD) were generated from CT scans collected as part of the COPDGene study (n = 8956). Volume density (V) and Euler-Poincaré Characteristic (χ) image maps, measures of the extent and coalescence of pocket formations (i.e., topologies), respectively, were determined for both PRMNorm and PRMfSAD. Association with COPD severity, emphysema, and spirometric measures were assessed via multivariable regression models. Readouts were evaluated as inputs for predicting FEV1 decline using a machine learning model. RESULTS: Multivariable cross-sectional analysis of COPD subjects showed that V and χ measures for PRMfSAD and PRMNorm were independently associated with the amount of emphysema. Readouts χfSAD (ß of 0.106, p < 0.001) and VfSAD (ß of 0.065, p = 0.004) were also independently associated with FEV1% predicted. The machine learning model using PRM topologies as inputs predicted FEV1 decline over five years with an AUC of 0.69. CONCLUSIONS: We demonstrated that V and χ of fSAD and Norm have independent value when associated with lung function and emphysema. In addition, we demonstrated that these readouts are predictive of spirometric decline when used as inputs in a ML model. Our topological PRM approach using PRMfSAD and PRMNorm may show promise as an early indicator of emphysema onset and COPD progression.
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Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Estudios Transversales , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Volumen Espiratorio Forzado/fisiologíaRESUMEN
In Mycobacterium tuberculosis, â¼10% of its genome encodes the proline-glutamic acid and proline-proline-glutamic acid (PPE) family of proteins, some of which were recently established to be key players in mycobacterial virulence. PPE2 (Rv0256c) is one among these proteins that we found to have pleiotropic effects during mycobacterial infection. PPE2 weakens the innate immune system by disturbing NO and reactive oxygen species production and myeloid hematopoiesis. We showed that PPE2 is unique for having nuclear localization signal, DNA binding domain, and SRC homology 3 (PXXP) binding domain, which enable it to interfere with the host immune system. Interestingly, PPE2 is a secretary protein, expressed during active tuberculosis (TB) infection, and is involved in facilitating survival of M. tuberculosis Thus, PPE2 could be a valuable drug target for developing effective therapeutics against TB. In this article, we describe possible roles of PPE2 in TB pathogenesis and the importance of PPE2 as a novel therapeutic target against TB.
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Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Mycobacterium tuberculosis/patogenicidad , Animales , Humanos , Mycobacterium tuberculosis/metabolismo , Virulencia/fisiologíaRESUMEN
Some breast cancers are caused by hormonal imbalances, such as estrogen and progesterone. These hormones play a function in directing the growth of cancer cells. The hormone receptors in hormone receptor-positive breast cancer lead breast cells to proliferate out of control. Cancer therapy such as hormonal, targeted, radiation is still unsatisfactory because of these challenges namely multiple drug resistance (MDR), off-targeting, severe adverse effects. A novel aromatase inhibitor exemestane (Exe) exhibits promising therapy in breast cancer. This study aims to develop and optimize Exe-loaded lipid nanocapsules (LNCs) by using DSPC, PF68 and olive oil as lipid, surfactant and oil phase, respectively and to characterize the same. The prepared nanocapsules were investigated via in vitro cell culture and in vivo animal models. The LNCs exhibited cytotoxicity in MCF-7 cell lines and enhanced anti-cancer activity and reduced cardiotoxicity in DMBA-induced animal model when compared to the drug. Additionally, in vivo pharmacokinetics revealed a 4.2-fold increased oral bioavailability when compared with Exe suspension. This study demonstrated that oral administration of Exe-loaded LNCs holds promise for the antiestrogenic activity of exemestane in breast cancer.
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Nanocápsulas , Neoplasias , Animales , Liposomas , Androstadienos/farmacología , Androstadienos/uso terapéutico , Lípidos , Neoplasias/tratamiento farmacológicoRESUMEN
The purpose of this study was to evaluate the drug delivery and therapeutic potential of berberine (Br) loaded nanoformulation in rheumatoid arthritis (RA)-induced animal model. The Br-loaded NLCs (nanostructured lipid carriers) were prepared employing melt-emulsification process, and optimised through Box-Behnken design. The prepared NLCs were assessed for in-vitro and in-vivo evaluations. The optimised NLCs exhibited a mean diameter of 180.2 ± 0.31 nm with 88.32 ± 2.43% entrapment efficiency. An enhanced anti-arthritic activity with reduced arthritic scores to 0.66 ± 0.51, reduction in ankle diameter to 5.80 ± 0.27 mm, decline in paw withdrawal timing, and improvements in walking behaviour were observed in the Br-NLCs treated group. The radiographic images revealed a reduction in bone and cartilage deformation. The Br-NLCs showed promising results in the management of RA disease, can be developed as an efficient delivery system at commercial levels, and may be explored for clinical application after suitable experiments in the future.
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Artritis Reumatoide , Berberina , Nanoestructuras , Animales , Portadores de Fármacos/uso terapéutico , Berberina/farmacología , Berberina/uso terapéutico , Sistemas de Liberación de Medicamentos , Artritis Reumatoide/tratamiento farmacológico , Modelos Animales , Lípidos , Tamaño de la PartículaRESUMEN
Iron is an essential element for Mycobacterium tuberculosis; it has at least 40 enzymes that require iron as a cofactor. Accessibility of iron at the phagosomal surface inside macrophage is crucial for survival and virulence of M. tuberculosis ESAT-6, a 6-kDa-secreted protein of region of difference 1, is known to play a crucial role in virulence and pathogenesis of M. tuberculosis In our earlier study, we demonstrated that ESAT-6 protein interacts with ß-2-microglobulin (ß2M) and affects class I Ag presentation through sequestration of ß2M inside endoplasmic reticulum, which contributes toward inhibition of MHC class I:ß2M:peptide complex formation. The 6 aa at C-terminal region of ESAT-6 are essential for ESAT6:ß2M interaction. ß2M is essential for proper folding of HFE, CD1, and MHC class I and their surface expression. It is known that M. tuberculosis recruit holotransferrin at the surface of the phagosome. But the upstream mechanism by which it modulates holotransferrin-mediated iron uptake at the surface of macrophage is not well understood. In the current study, we report that interaction of the ESAT-6 protein with ß2M causes downregulation of surface HFE, a protein regulating iron homeostasis via interacting with transferrin receptor 1 (TFR1). We found that ESAT-6:ß2M interaction leads to sequestration of HFE in endoplasmic reticulum, causing poorer surface expression of HFE and HFE:TFR1 complex (nonfunctional TFR1) in peritoneal macrophages from C57BL/6 mice, resulting in increased holotransferrin-mediated iron uptake in these macrophages. These studies suggest that M. tuberculosis probably targets the ESAT-6 protein to increase iron uptake.
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Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Regulación hacia Abajo/fisiología , Proteína de la Hemocromatosis/metabolismo , Macrófagos Peritoneales/metabolismo , Mycobacterium tuberculosis/metabolismo , Transferrina/metabolismo , Animales , Transporte Biológico/fisiología , Retículo Endoplásmico/metabolismo , Hierro/metabolismo , Ratones , Ratones Endogámicos C57BL , Receptores de Transferrina/metabolismo , Virulencia/fisiología , Microglobulina beta-2/metabolismoRESUMEN
Zinc (Zn), an important microelement in ruminant diet, plays a critical role in various enzymes, hormones and functional proteins involved in nutrient metabolism. The present study was conducted to assess the effect of zinc hydroxychloride (Zn5(OH)8Cl2·H2O [ZnOHCl] and zinc sulphate (ZnSO4) on nutrient utilisation, mineral metabolism and biomarkers pertaining to growth performance in pre-ruminant crossbred calves. Twenty-four crossbred calves [body weight (BW); 31.03 ± 4.30 kg; age 10 d] were randomly allocated to four treatment groups (n = 6), i.e. no supplementation of Zn (0 mg/kg dry matter [DM]), 80 mg/kg DM Zn as ZnSO4(ZnS-80), 40 mg/kg DM Zn as ZnOHCl (ZnH-40) and 80 mg/kg DM Zn as ZnOHCl (ZnH-80) for 90 d experimental period. Results showed that dietary Zn supplementation improved (p < 0.05) feed intake, BW, average daily gain, heart girth, body length, plasma growth hormone, insulin-like growth factor and thyroxin concentration; however, nutrient digestibility remained unaffected among the groups. Addition of Zn increased (p < 0.05) Zn retention and plasma Zn concentration without affecting retention and plasma concentration of other minerals. Retention of Zn was the highest in ZnH-80 group followed by ZnH-40, ZnS-80 and lowest in control group. Overall results of the present study indicate that regardless of sources and levels, Zn supplementation increased growth performance, plasma Zn concentration and hormones levels in pre-ruminant crossbred calves. However, supplementation of hydroxy Zn at 40 mg/kg DM had similar effect as produced by ZnSO4 or ZnOHCl at a supplementation level of 80 mg/kg DM. Therefore, from the present study it can be concluded that ZnOHCl can be used as a Zn source for pre-ruminant calves at a lower dose compared to ZnSO4.
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Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Suplementos Dietéticos , Nutrientes/metabolismo , Zinc , Alimentación Animal/análisis , Animales , Biomarcadores , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Minerales/sangre , Zinc/administración & dosificaciónRESUMEN
Dietary strategies aiming at minimizing enteric methane (CH4) emission in ruminants are of practical interest from nutritional, economical, and environmental point of view. The present study evaluated the effects of supplementing Leucaena leucocephala leaves either alone or in conjunction with malic acid on nutrient utilization, growth performance, and enteric CH4 emission in crossbred cattle fed wheat straw and concentrate-based diet under tropical conditions. Eighteen crossbred (Karan-Fries) calves were randomly allocated into 3 groups: G-I (control)-fed wheat (Triticum aestivum) straw and concentrate mixture in the ratio 50:50; G-II-fed wheat straw, concentrate mixture, and Leucaena leucocephala leaves in the ratio 45:45:10; and (3) G-III-fed similar diet like G-II with an additional supplementation of 1% malic acid on dry matter intake basis. Experimental feeding spanning 90 days included a 7-day metabolism trial and CH4 quantification study by sulfur hexafluoride tracer technique. Results revealed no significant effect of dietary treatments on dry matter intake (DMI) and digestibility of nutrients, except neutral detergent fiber (NDF) digestibility which was 5.5% higher (P < 0.05) in G-III as compared to control. Further, nitrogen (N) metabolism, rumen microbial protein synthesis, and growth performance remained similar among the treatments. No significant effect was also observed for enteric CH4 emission (expressed as g/day and g/kg DMI) in calves supplemented with Leucaena leucocephala leaves and malic acid. Therefore, the present findings depict modest improvement in fiber digestibility with no encouraging effect in mitigating enteric CH4 in growing cattle calves by supplementing Leucaena leucocephala leaves alone or with malic acid within the selected levels.
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Digestión , Metano , Alimentación Animal/análisis , Animales , Bovinos , Dieta/veterinaria , Fermentación , Malatos , Metano/metabolismo , Nutrientes , Hojas de la Planta , Rumen/metabolismo , Clima TropicalRESUMEN
There is a need for newer feed additives due to legal prohibition on inclusion of growth promoting antibiotics in livestock diets in several countries due to antimicrobial resistance. In this context, rare earth elements (REE) have gained attention among animal nutritionists as potential growth promoters. Currently, several studies have reported better weight gain, milk production, egg laying capacity and feed conversion efficiency among different breeds of farm animals following supplementation with REE, with however largely inconsistent results. Furthermore, REE supplementation has also shown to improve ruminal fibrolytic and proteolytic activities as well as flavor of meat with negligible residues in edible tissue, however the mechanism behind this action is still unclear. According to existing research, due to their poor absorption and similarity with calcium REE might exert their action locally on gut microbial populations within the gastrointestinal tract (GIT). Moreover, REE have also shown anti-inflammatory, anti-oxidative as well as immune stimulating effects. The present review aims to broaden the knowledge about use of REE as feed additives for livestock and sum up efficacy of REE supplementation on performance and health of animals by comparing the findings. Till date, researches with REE have shown properties that make them a promising, new and safe alternative feed additive but further exploration is recommended to optimize effects and clarify discrepancy of various results before practical proposals can be drafted.
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Bacterial peptidyl-tRNA hydrolase (Pth; EC 3.1.1.29) hydrolyzes the peptidyl-tRNAs accumulated in the cytoplasm and thereby prevents cell death by alleviating tRNA starvation. X-ray and NMR studies of Vibrio cholerae Pth (VcPth) and mutants of its key residues involved in catalysis show that the activity and selectivity of the protein depends on the stereochemistry and dynamics of residues H24, D97, N118, and N14. D97-H24 interaction is critical for activity because it increases the nucleophilicity of H24. The N118 and N14 have orthogonally competing interactions with H24, both of which reduce the nucleophilicity of H24 and are likely to be offset by positioning of a peptidyl-tRNA substrate. The region proximal to H24 and the lid region exhibit slow motions that may assist in accommodating the substrate. Helix α3 exhibits a slow wobble with intermediate time scale motions of its N-cap residue N118, which may work as a flypaper to position the scissile ester bond of the substrate. Overall, the dynamics of interactions between the side chains of N14, H24, D97, and N118, control the catalysis of substrate by this enzyme.
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Proteínas Bacterianas/química , Hidrolasas de Éster Carboxílico/química , Aminoacil-ARN de Transferencia/química , Vibrio cholerae/química , Secuencias de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biocatálisis , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Dominio Catalítico , Clonación Molecular , Cristalografía por Rayos X , Estabilidad de Enzimas , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Cinética , Simulación de Dinámica Molecular , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Aminoacil-ARN de Transferencia/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Termodinámica , Vibrio cholerae/enzimologíaRESUMEN
Rv3488 of Mycobacterium tuberculosis H37Rv has been assigned to the phenolic acid decarboxylase repressor (PadR) family of transcriptional regulators that play key roles in multidrug resistance and virulence of prokaryotes. The binding of cadmium, zinc, and several other metals to Rv3488 was discovered and characterized by isothermal titration calorimetery to be an exothermic process. Crystal structures of apo-Rv3488 and Rv3488 in complex with cadmium or zinc ions were determined by X-ray crystallography. The structure of Rv3488 revealed a dimeric protein with N-terminal winged-helix-turn-helix DNA-binding domains composed of helices α1, α2, α3, and strands ß1 and ß2, with the dimerization interface being formed of helices α4 and α1. The overall fold of Rv3488 was similar to PadR-s2 and metal sensor transcriptional regulators. In the crystal structure of Rv3488-Cd complex, two octahedrally coordinated Cd2+ ions were present, one for each subunit. The same sites were occupied by zinc ions in the structure of Rv3488-Zn, with two additional zinc ions complexed in one monomer. EMSA studies showed specific binding of Rv3488 with its own 30-bp promoter DNA. The functional role of Rv3488 was characterized by expressing the rv3488 gene under the control of hsp60 promoter in Mycobacterium smegmatis Expression of Rv3488 increased the intracellular survival of recombinant M. smegmatis in murine macrophage cell line J774A.1 and also augmented its tolerance to Cd2+ ions. Overall, the studies show that Rv3488 may have transcription regulation and metal-detoxifying functions and its expression in M. smegmatis increases intracellular survival, perhaps by counteracting toxic metal stress.
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Proteínas Bacterianas/genética , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Mycobacterium tuberculosis/genética , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Línea Celular , Cristalografía por Rayos X , Metales/química , Metales/metabolismo , Ratones , Modelos Moleculares , Mycobacterium/clasificación , Mycobacterium/genética , Mycobacterium/metabolismo , Mycobacterium tuberculosis/metabolismo , Unión Proteica , Conformación Proteica , Multimerización de Proteína , Conejos , Homología de Secuencia de AminoácidoRESUMEN
The present study was aimed at preparing and evaluating levocetirizine (LCZD) loaded emulgel containing tamanu oil and sericin for atopic dermatitis (AD) therapy. The emulgel envisaged topical delivery of LCZD utilising natural antioxidants for superior therapeutic outcomes when compared with other conventional therapy. Tamanu oil based microemulsion (ME) was optimised utilising Box-Behnken design (BBD). The OPT-ME displayed globule size 379.5 ± 2.33 nm, polydispersity index 0.284, drug loading 0.41 ± 0.01% w/w, entrapment efficiency 94.34 ± 2.11% w/w and drug release 86.24 ± 4.90% respectively over a period of 24 h. The optimised formulation (OPT-ME) was further incorporated into sericin gel to form emulgel (LSE). In vivo pharmacodynamic studies revealed enhanced therapeutic potential of emulgel in terms of reduced scratching frequency and erythema score when compared with conventional gel. The superior therapeutic potential was further witnessed through histopathological and biochemical studies. The emulgel can be an alternative appropriate dosage form for the treatment of AD.
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Cetirizina/administración & dosificación , Dermatitis Atópica/tratamiento farmacológico , Emulsiones/química , Aceites de Plantas/química , Sericinas/química , Animales , Bombyx/química , Calophyllum/química , Cetirizina/farmacocinética , Cetirizina/uso terapéutico , Chlorocebus aethiops , Dermatitis Atópica/inducido químicamente , Dermatitis Atópica/patología , Dinitroclorobenceno , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Masculino , Ratas Wistar , Absorción Cutánea , Células VeroRESUMEN
BACKGROUND: Bacterial peptidyl-tRNA hydrolase (Pth) is an essential enzyme that alleviates tRNA starvation by recycling prematurely dissociated peptidyl-tRNAs. The specificity of Pth for N-blocked-aminoacyl-tRNA has been proposed to be contingent upon conserved residue N14 forming a hydrogen bond with the carbonyl of the first peptide bond in the substrate. M71 is involved in forming a conserved hydrogen bond with N14. Other interactions facilitating this recognition are not known. METHODS: The structure, dynamics, and stability of the M71A mutant of Pth from Vibrio cholerae (VcPth) were characterized by X-ray crystallography, NMR spectroscopy, MD simulations and DSC. RESULTS: Crystal structure of M71A mutant was determined. In the structure, the dimer interface is formed by the insertion of six C-terminal residues of one molecule into the active site of another molecule. The side-chain amide of N14 was hydrogen bonded to the carbonyl of the last peptide bond formed between residues A196 and E197, and also to A71. The CSP profile of mutation was similar to that observed for the N14D mutant. M71A mutation lowered the thermal stability of the protein. CONCLUSION: Our results indicate that the interactions of M71 with N14 and H24 play an important role in optimal positioning of their side-chains relative to the peptidyl-tRNA substrate. Overall, these interactions of M71 are important for the activity, stability, and compactness of the protein. SIGNIFICANCE: The work presented provides original and new structural and dynamics information that significantly enhances our understanding of the network of interactions that govern this enzyme's activity and selectivity.
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Hidrolasas de Éster Carboxílico/metabolismo , Metionina/metabolismo , Proteínas Recombinantes/genética , Vibrio cholerae/enzimología , Hidrolasas de Éster Carboxílico/genética , Dominio Catalítico , Cristalografía por Rayos X , Citoplasma/metabolismo , Enlace de Hidrógeno , Espectroscopía de Resonancia Magnética , Simulación de Dinámica Molecular , Estructura Molecular , Conformación Proteica , Aminoacil-ARN de Transferencia/genética , Aminoacil-ARN de Transferencia/metabolismo , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Vibrio cholerae/genéticaRESUMEN
In mycobacteria, polyketide synthases and nonribosomal peptide synthetases (NRPSs) produce complex lipidic metabolites by using a thio-template mechanism of catalysis. In this study, we demonstrate that off-loading reductase (R) domain of mycobacterial NRPSs performs two consecutive [2 + 2]e(-) reductions to release thioester-bound lipopeptides as corresponding alcohols, using a nonprocessive mechanism of catalysis. The first crystal structure of an R domain from Mycobacterium tuberculosis NRPS provides strong support to this mechanistic model and suggests that the displacement of intermediate would be required for cofactor recycling. We show that 4e(-) reductases produce alcohols through a committed aldehyde intermediate, and the reduction of this intermediate is at least 10 times more efficient than the thioester-substrate. Structural and biochemical studies also provide evidence for the conformational changes associated with the reductive cycle. Further, we show that the large substrate-binding pocket with a hydrophobic platform accounts for the remarkable substrate promiscuity of these domains. Our studies present an elegant example of the recruitment of a canonical short-chain dehydrogenase/reductase family member as an off-loading domain in the context of assembly-line enzymology.
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Electrones , Mycobacterium tuberculosis/enzimología , Péptido Sintasas/química , Péptido Sintasas/metabolismo , Alcoholes/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Glicopéptidos/química , Glicopéptidos/metabolismo , Lipopéptidos/química , Lipopéptidos/metabolismo , Modelos Moleculares , NADP , Oxidación-Reducción , Oxidorreductasas/química , Oxidorreductasas/metabolismo , Estructura Terciaria de Proteína , Especificidad por SustratoRESUMEN
The current research aimed to assess the feasibility of using Zn hydroxy chloride (ZnOHCl) as an alternative to ZnSO4 in pre-ruminant crossbred calves. Twenty-four male crossbred calves (Tharparkar × Holstein Friesian) were categorized into four groups according to body weight and age (body weight 31 kg; age 10 days). Experimental calves were kept on a similar feeding regimen except that different groups were supplemented with either 0 mg Zn/kg DMI (Zn-0), 80 mg Zn/kg DMI as ZnSO4 (ZnS-80), 40 mg Zn/kg DMI as ZnOHCl (ZnH-40), or 80 mg Zn/kg DMI as ZnOHCl (ZnH-80). All the calves were fed for 90 days as per ICAR (2013) feeding standard to fulfill their nutrient requirements for growth rate of 500 g/day. The study observed the influence of different sources and varying levels of Zn supplementation over a 90-day experimental period on health status, hemato-biochemical attributes, antioxidant status, immune responses, and plasma minerals and erythrocyte Zn concentrations. The data was examined using a randomized complete block design (RCBD) with fixed effects of treatment, period, and their interaction. The results indicated that irrespective of the sources and levels of Zn, supplementation did not lead to significant changes in health status as assessed by fecal score, nasal score, ear score, and eye score. Hematological parameters remained unchanged following supplementation with different sources and levels of Zn. Zn-supplemented groups showed higher levels of total protein, globulin, and alkaline phosphates (ALP) compared to the non-supplemented group. However, no significant variations were detected within the Zn-supplemented groups. Zinc supplementation significantly increased total antioxidant capacity (TAC), antioxidant enzyme activity, total immunoglobulin (Ig), immunoglobulin G (IgG), cell-mediated immunity (CMI), and humoral immunity (HI); however, no significant variations were detected among Zn-supplemented groups. Zn supplementation enhanced plasma and RBC Zn concentration without affecting the plasma concentration of other minerals. However, among the Zn-supplemented groups, 80 mg Zn/kg DMI as ZnOHCl resulted in the highest RBC Zn concentration. The study results demonstrate that Zn supplementation enhanced biomarkers of zinc status, antioxidant levels, and immune responses in pre-ruminant crossbred calves. Nevertheless, no significant variations were observed between the different Zn sources (ZnSO4 and ZnOHCl) utilized in this study. Research suggests that ZnOHCl could be a feasible alternative to ZnSO4 in the diet of pre-ruminant crossbred calves.
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Doxorubicin is a powerful chemotherapy medicine that is frequently used to treat cancer, but because of its extremely destructive side effects on other healthy cells, its applications have been severely constrained. With the aim of using lower therapeutic doses of doxorubicin while maintaining the same anti-cancerous activity as those of higher doses, the present study designs nano-encapsulation of doxorubicin by acrylamide grafted melanin as core and acrylic acid grafted flax seed gum as shell (DOX@AAM-g-ML/AA-g-FSG-NPs) for studies in-vivo and in-vitro anticancer activity. For biological studies, the cytotoxicity of DOX@AAM-g-ML/AA-g-FSG-NPs was examined on a cancerous human cell line (HCT-15) and it was observed that DOX@AAM-g-ML/AA-g-FSG-NPs exhibited very high toxicity towards HCT-15. In-vivo investigation in colon cancer-inflicted rat model also showed that DOX@AAM-g-ML/AA-g-FSG-NPs showed better anticancer activity against cancerous cells as compared to free doxorubicin. The drug release behavior of DOX@GML-GFS-NPs was studied at several pH and maximum drug release (95 %) was recorded at pH -7.2, and kinetic data of drug release was follows the Higuchi (R2 = 0.9706) kinetic model. Our study is focussed on reducing the side effects of doxorubicin by its nano-encapsulation in acrylamide grafted melanin as core and acrylic acid grafted flax seed gum that will also enhance its efficiency.
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Acrilatos , Lino , Nanopartículas , Neoplasias , Ratas , Humanos , Animales , Melaninas , Nanopartículas/uso terapéutico , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Neoplasias/tratamiento farmacológico , Acrilamidas , Portadores de Fármacos , Sistemas de Liberación de MedicamentosRESUMEN
Wounds pose a formidable challenge in healthcare, necessitating the exploration of innovative tissue-healing solutions. Traditional wound dressings exhibit drawbacks, causing tissue damage and impeding natural healing. Using a Microwave (MW)-)-assisted technique, we envisaged a novel hydrogel (Hg) scaffold to address these challenges. This hydrogel scaffold was created by synthesizing a pH-responsive crosslinked material, specifically locust bean gum-grafted-poly(acrylamide-co-acrylic acid) [LBG-g-poly(AAm-co-AAc)], to enable sustained release of c-phycocyanin (C-Pc). Synthesized LBG-g-poly(AAm-co-AAc) was fine-tuned by adjusting various synthetic parameters, including the concentration of monomers, duration of reaction, and MW irradiation intensity, to maximize the yield of crosslinked LBG grafted product and enhance encapsulation efficiency of C-Pc. Following its synthesis, LBG-g-poly(AAm-co-AAc) was thoroughly characterized using advanced techniques, like XRD, TGA, FTIR, NMR, and SEM, to analyze its structural and chemical properties. Moreover, the study examined the in-vitro C-Pc release profile from LBG-g-poly(AAm-co-AAc) based hydrogel (HgCPcLBG). Findings revealed that the maximum release of C-Pc (64.12 ± 2.69 %) was achieved at pH 7.4 over 48 h. Additionally, HgCPcLBG exhibited enhanced antioxidant performance and compatibility with blood. In vivo studies confirmed accelerated wound closure, and ELISA findings revealed reduced inflammatory markers (IL-6, IL-1ß, TNF-α) within treated skin tissue, suggesting a positive impact on injury repair. A low-cost and eco-friendly approach for creating LBG-g-poly(AAm-co-AAc) and HgCPcLBG has been developed. This method achieved sustained release of C-Pc, which could be a significant step forward in wound care technology.
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Acrilamida , Galactanos , Hidrogeles , Mananos , Gomas de Plantas , Polimerizacion , Cicatrización de Heridas , Gomas de Plantas/química , Mananos/química , Galactanos/química , Cicatrización de Heridas/efectos de los fármacos , Concentración de Iones de Hidrógeno , Animales , Hidrogeles/química , Acrilamida/química , Masculino , Acrilatos/química , Preparaciones de Acción Retardada , Liberación de Fármacos , Microondas , Ratas , AcrilamidasRESUMEN
Background and Objective: Detection of the dicrotic notch (DN) within a cardiac cycle is essential for assessment of cardiac output, calculation of pulse wave velocity, estimation of left ventricular ejection time, and supporting feature-based machine learning models for noninvasive blood pressure estimation, and hypotension, or hypertension prediction. In this study, we present a new algorithm based on the iterative envelope mean (IEM) method to detect automatically the DN in arterial blood pressure (ABP) and photoplethysmography (PPG) waveforms. Methods: The algorithm was evaluated on both ABP and PPG waveforms from a large perioperative dataset (MLORD dataset) comprising 17,327 patients. The analysis involved a total of 1,171,288 cardiac cycles for ABP waveforms and 3,424,975 cardiac cycles for PPG waveforms. To evaluate the algorithm's performance, the systolic phase duration (SPD) was employed, which represents the duration from the onset of the systolic phase to the DN in the cardiac cycle. Correlation plots and regression analysis were used to compare the algorithm with an established DN detection technique (second derivative). The marking of the DN temporal location was carried out by an experienced researcher using the help of the 'find_peaks' function from the scipy PYTHON package, serving as a reference for the evaluation. The marking was visually validated by both an engineer and an anesthesiologist. The robustness of the algorithm was evaluated as the DN was made less visually distinct across signal-to-noise ratios (SNRs) ranging from -30 dB to -5 dB in both ABP and PPG waveforms. Results: The correlation between SPD estimated by the algorithm and that marked by the researcher is strong for both ABP (R2(87343) =.99, p<.001) and PPG (R2(86764) =.98, p<.001) waveforms. The algorithm had a lower mean error of dicrotic notch detection (s): 0.0047 (0.0029) for ABP waveforms and 0.0046 (0.0029) for PPG waveforms, compared to 0.0693 (0.0770) for ABP and 0.0968 (0.0909) for PPG waveforms for the established 2nd derivative method. The algorithm has high accuracy of DN detection for SNR of >= -9 dB for ABP waveforms and >= -12 dB for PPG waveforms indicating robust performance in detecting the DN when it is less visibly distinct. Conclusion: Our proposed IEM- based algorithm can detect DN in both ABP and PPG waveforms with low computational cost, even in cases where it is not distinctly defined within a cardiac cycle of the waveform ('DN-less signals'). The algorithm can potentially serve as a valuable, fast, and reliable tool for extracting features from ABP and PPG waveforms. It can be especially beneficial in medical applications where DN-based features, such as SPD, diastolic phase duration, and DN amplitude, play a significant role.
RESUMEN
BACKGROUND AND OBJECTIVE: Detection of the dicrotic notch (DN) within a cardiac cycle is essential for assessment of cardiac output, calculation of pulse wave velocity, estimation of left ventricular ejection time, and supporting feature-based machine learning models for noninvasive blood pressure estimation, and hypotension, or hypertension prediction. In this study, we present a new algorithm based on the iterative envelope mean (IEM) method to detect automatically the DN in arterial blood pressure (ABP) and photoplethysmography (PPG) waveforms. METHODS: The algorithm was evaluated on both ABP and PPG waveforms from a large perioperative dataset (MLORD dataset) comprising 17,327 patients. The analysis involved a total of 1,171,288 cardiac cycles for ABP waveforms and 3,424,975 cardiac cycles for PPG waveforms. To evaluate the algorithm's performance, the systolic phase duration (SPD) was employed, which represents the duration from the onset of the systolic phase to the DN in the cardiac cycle. Correlation plots and regression analysis were used to compare the algorithm against marked DN detection, while box plots and Bland-Altman plots were used to compare its performance with both marked DN detection and an established DN detection technique (second derivative). The marking of the DN temporal location was carried out by an experienced researcher using the help of the 'find_peaks' function from the scipy Python package, serving as a reference for the evaluation. The marking was visually validated by both an engineer and an anesthesiologist. The robustness of the algorithm was evaluated as the DN was made less visually distinct across signal-to-noise ratios (SNRs) ranging from -30 dB to -5 dB in both ABP and PPG waveforms. RESULTS: The correlation between SPD estimated by the algorithm and that marked by the researcher is strong for both ABP (R2(87,343) =0.99, p<.001) and PPG (R2(86,764) =0.98, p<.001) waveforms. The algorithm had a lower mean error of DN detection (s): 0.0047 (0.0029) for ABP waveforms and 0.0046 (0.0029) for PPG waveforms, compared to 0.0693 (0.0770) for ABP and 0.0968 (0.0909) for PPG waveforms for the established 2nd derivative method. The algorithm has high rate of detectability of DN detection for SNR of >= -9 dB for ABP waveforms and >= -12 dB for PPG waveforms indicating robust performance in detecting the DN when it is less visibly distinct. CONCLUSION: Our proposed IEM- based algorithm can detect DN in both ABP and PPG waveforms with low computational cost, even in cases where it is not distinctly defined within a cardiac cycle of the waveform ('DN-less signals'). The algorithm can potentially serve as a valuable, fast, and reliable tool for extracting features from ABP and PPG waveforms. It can be especially beneficial in medical applications where DN-based features, such as SPD, diastolic phase duration, and DN amplitude, play a significant role.
Asunto(s)
Algoritmos , Fotopletismografía , Fotopletismografía/métodos , Humanos , Presión Arterial , Determinación de la Presión Sanguínea/métodos , Análisis de la Onda del Pulso/métodos , Procesamiento de Señales Asistido por ComputadorRESUMEN
Acyl-Coenzyme A binding domain containing proteins (ACBDs) are ubiquitous in nearly all eukaryotes. They can exist as a free protein, or a domain of a large, multidomain, multifunctional protein. Besides modularity, ACBDs also display multiplicity. The same organism may have multiple ACBDs, differing in sequence and organization. By virtue of this diversity, ACBDs perform functions ranging from transport, synthesis, trafficking, signal transduction, transcription, and gene regulation. In plants and some microorganisms, these ACBDs are designated ACBPs (acyl-CoA binding proteins). The simplest ACBD/ACBP is a small, â¼10 kDa, soluble protein, comprising the acyl-CoA binding (ACB) domain. Most of these small ACBDs exist as monomers, while a few show a tendency to oligomerize. In sync with those studies, we report the crystal structure of two ACBDs from Leishmania major, named ACBP103, and ACBP96 based on the number of residues present. Interestingly, ACBP103 crystallized as a monomer and a dimer under different crystallization conditions. Careful examination of the dimer disclosed an exposed 'AXXA' motif in the helix I of the two ACBP103 monomers, aligned in a head-to-tail arrangement in the dimer. Glutaraldehyde cross-linking studies confirm that apo-ACBP103 can self-associate in solution. Isothermal titration calorimetry studies further show that ACBP103 can bind ligands ranging from C8 - to C20-CoA, and the data could be best fit to a 'two sets of sites'/sequential binding site model. Taken together, our studies show that Leishmania major ACBP103 can self-associate in the apo-form through a unique dimerization motif, an interaction that may play an important role in its function.
Asunto(s)
Secuencias de Aminoácidos , Leishmania major , Multimerización de Proteína , Leishmania major/metabolismo , Leishmania major/genética , Acilcoenzima A/metabolismo , Acilcoenzima A/química , Cristalografía por Rayos X , Unión Proteica , Proteínas Protozoarias/química , Proteínas Protozoarias/metabolismo , Proteínas Protozoarias/genética , Secuencia de Aminoácidos , Modelos Moleculares , Sitios de UniónRESUMEN
Rv1176c of Mycobacterium tuberculosis H37Rv belongs to the PadR-s1 subfamily of the PadR family of protein. Rv1176c forms a stable dimer in solution. Its stability is characterized by a thermal melting transition temperature (Tm) of 39.4⯰C. The crystal structure of Rv1176c was determined at a resolution of 2.94â¯Å, with two monomers in the asymmetric unit. Each monomer has a characteristic N-terminal winged-helix-turn-helix DNA-binding domain. Rv1176c C-terminal is a coiled-coil dimerization domain formed of α-helices α5 to α7. In the Rv1176c dimer, there is domain-swapping of the C-terminal domain in comparison to other PadR homologs. In the dimer, there is a long inter-subunit tunnel in which different ligands can bind. Rv1176c was found to bind to the promoter region of its own gene with high specificity. M. smegmatis MC2 155 genome lacks homolog of Rv1176c. Therefore, it was used as a surrogate to characterize the functional role of Rv1176c. Expression of Rv1176c in M. smegmatis MC2 155 cells imparted enhanced tolerance towards oxidative stress. Rv1176c expressing M. smegmatis MC2 155 cells exhibited enhanced intracellular survival in J774A.1 murine macrophage cells. Overall, our studies demonstrate Rv1176c to be a PadR-s1 subfamily transcription factor that can moderate the effect of oxidative stress.