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1.
J Genet Eng Biotechnol ; 22(2): 100376, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38797551

RESUMO

Jute (Corchorus sp.), a commercially important and eco-friendly crop, is widely cultivated in Bangladesh, India, and China. Some varieties of this tropical plant such as the Corchorus olitorius. Variety accession no. 2015 (acc. 2015) has been found to be low-temperature tolerant. The current study was designed to explore the genome-wide variations present in the tolerant plant acc. 2015 in comparison to the sensitive farmer popular variety Corchorus olitorius var. O9897 using the whole genome resequencing technique. Among different variations, intergenic Single Nucleotide Polymorphism (SNPs) and Insertion-Deletion (InDels) were found in the highest percentage whereas approximately 3% SNPs and 2% InDels were found in exonic regions in both plants. Gene enrichment analysis indicated the presence of acc. 2015 specific SNPs in the genes encoding peroxidase, ER lumen protein retaining receptor, and hexosyltransferase involved in stress response (GO:0006950) which were not present in sensitive variety O9897. Besides, distinctive copy number variation regions (CNVRs) comprising 120 gene loci were found in acc. 2015 with a gain of function from multiple copy numbers but absent in O9897. Gene ontology analysis revealed these gene loci to possess different receptors like kinases, helicases, phosphatases, transcription factors especially Myb transcription factors, regulatory proteins containing different binding domains, annexin, laccase, acyl carrier protein, potassium transporter, and vesicular transporter proteins that are responsible for low temperature induced adaptation pathways in plants. This work of identifying genomic variations linked to cold stress tolerance traits will help to develop successful markers that will pave the way to develop genetically modified cold-resistant jute lines for year-round cultivation to meet the demand for a sustainable fiber crop economy.

2.
Comput Biol Med ; 176: 108555, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38749323

RESUMO

Cardiovascular diagnostics relies heavily on the ECG (ECG), which reveals significant information about heart rhythm and function. Despite their significance, traditional ECG measures employing electrodes have limitations. As a result of extended electrode attachments, patients may experience skin irritation or pain, and motion artifacts may interfere with signal accuracy. Additionally, ECG monitoring usually requires highly trained professionals and specialized equipment, which increases the treatment's complexity and cost. In critical care scenarios, such as continuous monitoring of hospitalized patients, wearable sensors for collecting ECG data may be difficult to use. Although there are issues with ECG, it remains a valuable tool for diagnosing and monitoring cardiac disorders due to its non-invasive nature and the detailed information it provides about the heart. The goal of this study is to present an innovative method for generating continuous ECG waveforms from non-contact radar data by using Deep Learning. The method can eliminate the need for invasive or wearable biosensors and expensive equipment to collect ECGs. In this paper, we propose the MultiResLinkNet, a one-dimensional convolutional neural network (1D CNN) model for generating ECG signals from radar waveforms. With the help of a publicly accessible radar benchmark dataset, an end-to-end DL architecture is trained and assessed. There are six ports of raw radar data in this dataset, along with ground truth physiological signals collected from 30 participants in five distinct scenarios: Resting, Valsalva, Apnea, Tilt-up, and Tilt-down. By using strong temporal and spectral measurements, we assessed our proposed framework's ability to convert ECG data from Radar signals in three distinct scenarios, namely Resting, Valsalva, and Apnea (RVA). ECG segmentation performed better by MultiResLinkNet than by state-of-the-art networks in both combined and individual cases. As a result of the simulations, the resting, valsalva, and RVA scenarios showed the highest average temporal values, respectively: 66.09523 ± 19.33, 60.13625 ± 21.92, and 61.86265 ± 21.37. In addition, it exhibited the highest spectral correlation values (82.4388 ± 18.42 (Resting), 77.05186 ± 23.26 (Valsalva), 74.65785 ± 23.17 (Apnea), and 79.96201 ± 20.82 (RVA)), along with minimal temporal and spectral errors in almost every case. The qualitative evaluation revealed strong similarities between generated and actual ECG waveforms. As a result of our method of forecasting ECG patterns from remote radar data, we can monitor high-risk patients, especially those undergoing surgery.


Assuntos
Aprendizado Profundo , Eletrocardiografia , Radar , Processamento de Sinais Assistido por Computador , Humanos , Eletrocardiografia/métodos
3.
J Pharm Bioallied Sci ; 16(Suppl 1): S583-S585, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595609

RESUMO

Background: Periodontal disease, characterized by inflammation and damage to tooth-supporting structures, poses a prevalent oral health concern. Early detection is crucial for effective management. Materials and Methods: This study comprised of 60 patients with varying degrees of periodontal disease. Intraoral images were captured using digital cameras, and AI algorithms were trained to analyze these images for signs of periodontal disease. Clinical diagnoses, conducted by experienced periodontal specialists, were used as the reference standard. Results: The AI algorithms achieved an overall accuracy of 87% in diagnosing periodontal disease. Sensitivity was 90%, indicating the AI's ability to correctly identify 90% of true cases, while specificity stood at 84%, demonstrating its capability to accurately classify 84% of non-diseased cases. In comparison, clinical diagnosis yielded an overall accuracy of 86%. Statistical analysis showed no significant difference between AI-based diagnosis and clinical examination (P > 0.05). Conclusion: This study underscores the promising potential of AI algorithms in diagnosing periodontal disease through intraoral image analysis.

4.
Bioengineering (Basel) ; 10(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37237649

RESUMO

Electroencephalogram (EEG) signals immensely suffer from several physiological artifacts, including electrooculogram (EOG), electromyogram (EMG), and electrocardiogram (ECG) artifacts, which must be removed to ensure EEG's usability. This paper proposes a novel one-dimensional convolutional neural network (1D-CNN), i.e., MultiResUNet3+, to denoise physiological artifacts from corrupted EEG. A publicly available dataset containing clean EEG, EOG, and EMG segments is used to generate semi-synthetic noisy EEG to train, validate and test the proposed MultiResUNet3+, along with four other 1D-CNN models (FPN, UNet, MCGUNet, LinkNet). Adopting a five-fold cross-validation technique, all five models' performance is measured by estimating temporal and spectral percentage reduction in artifacts, temporal and spectral relative root mean squared error, and average power ratio of each of the five EEG bands to whole spectra. The proposed MultiResUNet3+ achieved the highest temporal and spectral percentage reduction of 94.82% and 92.84%, respectively, in EOG artifacts removal from EOG-contaminated EEG. Moreover, compared to the other four 1D-segmentation models, the proposed MultiResUNet3+ eliminated 83.21% of the spectral artifacts from the EMG-corrupted EEG, which is also the highest. In most situations, our proposed model performed better than the other four 1D-CNN models, evident by the computed performance evaluation metrics.

5.
Sci Data ; 10(1): 214, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37062771

RESUMO

The silver pride of Bangladesh, migratory shad, Tenualosa ilisha (Hilsa), makes the highest contribution to the total fish production of Bangladesh. Despite its noteworthy contribution, a well-annotated transcriptome data is not available. Here we report a transcriptomic catalog of Hilsa, constructed by assembling RNA-Seq reads from different tissues of the fish including brain, gill, kidney, liver, and muscle. Hilsa fish were collected from different aquatic habitats (fresh, brackish, and sea water) and the sequencing was performed in the next generation sequencing (NGS) platform. De novo assembly of the sequences obtained from 46 cDNA libraries revealed 462,085 transcript isoforms that were subsequently annotated using the Universal Protein Resource Knowledgebase (UniPortKB) as a reference. Starting from the sampling to final annotation, all the steps along with the workflow are reported here. This study will provide a significant resource for ongoing and future research on Hilsa for transcriptome based expression profiling and identification of candidate genes.


Assuntos
Peixes , Transcriptoma , Animais , Peixes/genética , Perfilação da Expressão Gênica , Estudos de Associação Genética , Anotação de Sequência Molecular , Isoformas de Proteínas/genética
6.
Neural Regen Res ; 18(2): 289-292, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35900405

RESUMO

Traumatic brain injuries are serious clinical incidents associated with some of the poorest outcomes in neurological practice. Coupled with the limited regenerative capacity of the brain, this has significant implications for patients, carers, and healthcare systems, and the requirement for life-long care in some cases. Clinical treatment currently focuses on limiting the initial neural damage with long-term care/support from multidisciplinary teams. Therapies targeting neuroprotection and neural regeneration are not currently available but are the focus of intensive research. Biomaterial-based interventions are gaining popularity for a range of applications including biomolecule and drug delivery, and to function as cellular scaffolds. Experimental investigations into the development of such novel therapeutics for traumatic brain injury will be critically underpinned by the availability of appropriate high throughput, facile, ethically viable, and pathomimetic biological model systems. This represents a significant challenge for researchers given the pathological complexity of traumatic brain injury. Specifically, there is a concerted post-injury response mounted by multiple neural cell types which includes microglial activation and astroglial scarring with the expression of a range of growth inhibitory molecules and cytokines in the lesion environment. Here, we review common models used for the study of traumatic brain injury (ranging from live animal models to in vitro systems), focusing on penetrating traumatic brain injury models. We discuss their relative advantages and drawbacks for the developmental testing of biomaterial-based therapies.

7.
Molecules ; 27(6)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35335300

RESUMO

Shigella species account for the second-leading cause of deaths due to diarrheal diseases among children of less than 5 years of age. The emergence of multi-drug-resistant Shigella isolates and the lack of availability of Shigella vaccines have led to the pertinence in the efforts made for the development of new therapeutic strategies against shigellosis. Consequently, designing small-interfering RNA (siRNA) candidates against such infectious agents represents a novel approach to propose new therapeutic candidates to curb the rampant rise of anti-microbial resistance in such pathogens. In this study, we analyzed 264 conserved sequences from 15 different conserved virulence genes of Shigella sp., through extensive rational validation using a plethora of first-generation and second-generation computational algorithms for siRNA designing. Fifty-eight siRNA candidates were obtained by using the first-generation algorithms, out of which only 38 siRNA candidates complied with the second-generation rules of siRNA designing. Further computational validation showed that 16 siRNA candidates were found to have a substantial functional efficiency, out of which 11 siRNA candidates were found to be non-immunogenic. Finally, three siRNA candidates exhibited a sterically feasible three-dimensional structure as exhibited by parameters of nucleic acid geometry such as: the probability of wrong sugar puckers, bad backbone confirmations, bad bonds, and bad angles being within the accepted threshold for stable tertiary structure. Although the findings of our study require further wet-lab validation and optimization for therapeutic use in the treatment of shigellosis, the computationally validated siRNA candidates are expected to suppress the expression of the virulence genes, namely: IpgD (siRNA 9) and OspB (siRNA 15 and siRNA 17) and thus act as a prospective tool in the RNA interference (RNAi) pathway. However, the findings of our study require further wet-lab validation and optimization for regular therapeutic use for treatment of shigellosis.


Assuntos
Disenteria Bacilar , Shigella , Criança , Diarreia/tratamento farmacológico , Disenteria Bacilar/tratamento farmacológico , Disenteria Bacilar/genética , Humanos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Shigella/genética
8.
Materials (Basel) ; 16(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36614463

RESUMO

Spinal cord injury is debilitating with functional loss often permanent due to a lack of neuro-regenerative or neuro-therapeutic strategies. A promising approach to enhance biological function is through implantation of tissue engineered constructs, to offer neural cell replacement and reconstruction of the functional neuro-architecture. A key goal is to achieve spatially targeted guidance of regenerating tissue across the lesion site to achieve an aligned tissue structure lost as a consequence of injury. Electrospun nanofibres mimic the nanoscale architecture of the spinal cord, can be readily aligned, functionalised with pro-regenerative molecules and incorporated into implantable matrices to provide topographical cues. Crucially, electrospun nanofibers are routinely manufactured at a scale required for clinical use. Although promising, few studies have tested whether electrospun nanofibres can guide targeted spatial growth of clinically relevant neural stem/precursor populations. The alignment fate of daughter cells (derived from the pre-aligned parent cells) has also received limited attention. Further, a standardised quantification methodology to correlate neural cell alignment with topographical cues is not available. We have adapted an image analysis technique to quantify nanofibre-induced alignment of neural cells. Using this method, we show that two key neural stem/precursor populations of clinical relevance (namely, neural stem cells (NSCs) and oligodendrocyte precursor cells), reproducibly orientate their growth to aligned, high-density electrospun nanofiber meshes, but not randomly distributed ones. Daughter populations derived from aligned NSCs (neurons and astrocytes) maintained their alignment following differentiation, but oligodendrocytes did not. Our data show that pre-aligned transplant populations can be used to generate complex, multicellular aligned-fibre constructs for neural implantation.

9.
PLoS One ; 16(9): e0257863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34591915

RESUMO

The endophytic bacterium Burkholderia contaminans NZ was isolated from jute, which is an important fiber-producing plant. This bacterium exhibits significant growth promotion activity in in vivo pot experiments, and like other plant growth-promoting (PGP) bacteria fixes nitrogen, produces indole acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. B. contaminans NZ is considered to exert a promising growth inhibitory effect on Macrophomina phaseolina, a phytopathogen responsible for infecting hundreds of crops worldwide. This study aimed to identify the possibility of B. contaminans NZ as a safe biocontrol agent and assess its effectiveness in suppressing phytopathogenic fungi, especially M. phaseolina. Co-culture of M. phaseolina with B. contaminans NZ on both solid and liquid media revealed appreciable growth suppression of M. phaseolina and its chromogenic aberration in liquid culture. Genome mining of B. contaminans NZ using NaPDoS and antiSMASH revealed gene clusters that displayed 100% similarity for cytotoxic and antifungal substances, such as pyrrolnitrin. GC-MS analysis of B. contaminans NZ culture extracts revealed various bioactive compounds, including catechol; 9,10-dihydro-12'-hydroxy-2'-methyl-5'-(phenylmethyl)- ergotaman 3',6',18-trione; 2,3-dihydro-3,5- dihydroxy-6-methyl-4H-pyran-4-one; 1-(1,6-Dioxooctadecyl)- pyrrolidine; 9-Octadecenamide; and 2- methoxy- phenol. These compounds reportedly exhibit tyrosinase inhibitory, antifungal, and antibiotic activities. Using a more targeted approach, an RP-HPLC purified fraction was analyzed by LC-MS, confirming the existence of pyrrolnitrin in the B. contaminans NZ extract. Secondary metabolites, such as catechol and ergotaman, have been predicted to inhibit melanin synthesis in M. phaseolina. Thus, B. contaminans NZ appears to inhibit phytopathogens by apparently impairing melanin synthesis and other potential biochemical pathways, exhibiting considerable fungistatic activity.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Burkholderia/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Melaninas/biossíntese , Pirrolnitrina/biossíntese , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Agentes de Controle Biológico/farmacologia , Burkholderia/metabolismo , Técnicas de Cocultura , Produtos Agrícolas/microbiologia , Endófitos , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Indolacéticos/metabolismo , Fixação de Nitrogênio , Pirrolnitrina/farmacologia , Sequenciamento Completo do Genoma
10.
Heliyon ; 7(3): e06353, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33748456

RESUMO

In the backdrop of an abundance of lignin in jute, the main focus of the present study was to conduct a quality assessment of four delignified jute lines (in which four lignin biosynthetic genes were individually downregulated) across advanced generations for industrial applications. To this end, the transgenic lines were advanced to 7th (COMT and C4H lines) and 5th (C3H and F5H lines) transformed generations. The results exhibit approximately 16-25% reduction in acid-insoluble lignin for the whole stem and 13-14% reduction in fiber lignin content for all four transgenic lines compared to the control. The altered lignin composition led to a 3-6% increase in the cellulose content and a small improvement in the enzymatic release of glucose. Lignin reduction led to an exposure of the underlying fibrils in transgenic lines as observed through a scanning electron microscope whereas, it was undiscernible in the control fiber. Furthermore, an analysis of the mechanical properties appears almost similar to that of the control with no morphological deformities. Jute fibers from the transgenic lines offer tremendous cost-effective implications from an economic perspective.

11.
Can Pharm J (Ott) ; 148(6): 325-48, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26600824

RESUMO

BACKGROUND: Pharmacists in Canada have been prescribing since 2007. This review aims to explore the volume, array and nature of research activity on Canadian pharmacist prescribing and to identify gaps in the existing literature. METHODS: We conducted a scoping review to examine the literature on prescribing by pharmacists in Canada according to methodological trends, research areas and key findings. We searched for peer-reviewed research articles and abstracts in the Ovid MEDLINE, Ovid EMBASE and International Pharmaceutical Abstracts databases without any date limitations. A standardized form was used to extract information. RESULTS: We identified 156 articles; of these, 26 articles and 12 abstracts met inclusion criteria. One-half of the research studies (20) used quantitative methods, including surveys, trials and experimental designs; 11 studies used qualitative methods and 7 used other methods. Research on pharmacist prescribing demonstrated an improvement in patient outcomes (13 studies), varied stakeholder perceptions (10 studies) and factors that influence this practice change (11 studies). Pharmacist prescribing was adopted when pharmacists practised patient-centred care. Stakeholders held contrasting perceptions of pharmacist prescribing. DISCUSSION: Canadian research has demonstrated the benefit of pharmacist prescribing on patient outcomes, which is not present in the international literature. Future research may consider a meta-analysis addressing the impact on patient health. Gaps in research include comparisons between provinces, effects on physicians' services, overall patient safety and access to health care systems and economic implications for society. CONCLUSION: A growing body of research on pharmacist prescribing has captured the early impact of prescribing on patient outcomes, perceptions of practice and practice change. Opportunities exist for pan-Canadian research that examines the system impact.

12.
Dent Res J (Isfahan) ; 11(2): 222-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24932193

RESUMO

BACKGROUND: Endodontic leakage research focus mainly on the quality of the apical seal of the root canal system and the newly introduced resilon/epiphany system claim to be superior to Gutta-percha in respect to obturation procedure. The aim of this study is to evaluate the root canal obturation completed by resilon/epiphany system. MATERIALS AND METHODS: A total of 42 teeth were selected and were divided into four groups. Two experimental groups consisted of 15 teeth each and positive control group consisted of eight teeth and negative control group consisted of four teeth. In the experimental groups, Group 1 was obturated with resilon/epiphany system and Group 2 was obturated with Gutta-percha and endofil sealer by lateral condensation technique. The teeth were then immersed in Methelene blue solution and were split longitudinally to access the amount of dye penetrated in the canal. The specimens were viewed under scanning electron microscope to evaluate the adhesion of the obturating material to the root canal walls. Data was subjected to statistical analysis by Analysis of Variance and Bonferroni multiple comparison test at 1% level of significance. RESULTS: The resilon/epiphany system showed better adaptation to the root canal walls, but the difference in dye penetration was not statistically significant when compared to specimens obturated with Gutta-percha and endofil sealer. CONCLUSION: Although, there was no statistically significant difference between the groups, but resilon/epiphany system showed better adaptation to the root canal walls.

13.
Artigo em Inglês | MEDLINE | ID: mdl-23882368

RESUMO

The goal of this study was to assess the overtreatment of asymptomatic bacteriuria (ASB) in hospitalized patients, calculate the total costs of inappropriate treatment, and determine if a multi-faceted educational intervention was effective in reducing the overtreatment of ASB in a resource-limited community hospital. The study encompassed three phases: a retrospective pre-intervention assessment of the baseline cost and treatment of ASB, the implementation of a multi-faceted educational intervention, and a prospective post-intervention assessment of the efficacy of the intervention. A positive urine culture was defined by bacterial counts ≥10(5) cfu/mL. In the pre-intervention group, 64 (83%) of 109 patients were asymptomatic: 30 (47%) were treated. In the post-intervention group, 13 (17%) of 55 patients were asymptomatic: 2 (15%) were treated, (p=0.04). Fewer urine cultures were collected during the post-intervention period than the pre-intervention period (3,127 and 3,419, respectively) (p<0.001). The total cost of inappropriately treating ASB in the pre-intervention group was $1200 compared to $600 in the post-intervention group. The results demonstrated a significant decrease in the inappropriate treatment of ASB and the associated costs.

14.
Basic Clin Pharmacol Toxicol ; 109(5): 418-22, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21726409

RESUMO

Intravenous fat emulsion (IFE) is emerging as a novel antidote in clinical toxicology. Its current usage is extending beyond local anaesthetic toxicity into management of severe toxicity from some lipophilic drugs. We present a 51-year-old woman with severe bupropion toxicity whose haemodynamic status transiently improved after IFE. Serum analysis demonstrated an increase in serum concentration of hydroxybupropion, an active metabolite of bupropion, after IFE administration, lending support to one of the proposed mechanisms of IFE. A 51-year-old woman presented to the emergency department with generalised tonic-clonic convulsions lasting approximately 30 sec., and a wide complex rhythm on her ECG that was suggestive of myocardial sodium channel blockade. Despite sodium bicarbonate therapy, the patient developed profound hypotension refractory to high-dose norepinephrine. IFE was administered with haemodynamic improvement over the course of 30 min., followed by a significant decrease in norepinephrine requirement. The patient had an episode of ventricular tachycardia 24 hr after presentation, and received a second infusion of IFE. Analysis of serum for a panel of myocardial sodium channel blocking drugs revealed that significant bupropion ingestion had occurred. Bupropion poisoning may produce life-threatening clinical effects, and IFE may be considered in cases of severe haemodynamic instability. Further studies would be instrumental in determining the optimal clinical situations for utilisation of IFE.


Assuntos
Bupropiona/análogos & derivados , Ingestão de Alimentos , Emulsões Gordurosas Intravenosas/administração & dosagem , Antídotos/administração & dosagem , Bupropiona/sangue , Bupropiona/intoxicação , Eletrocardiografia/métodos , Feminino , Humanos , Hipotensão/tratamento farmacológico , Pessoa de Meia-Idade , Bicarbonato de Sódio/farmacologia , Taquicardia Ventricular/tratamento farmacológico , Taquicardia Ventricular/patologia
15.
Pak J Pharm Sci ; 23(2): 143-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20363690

RESUMO

The objective of this study was to observe the drug interaction between levofloxacin and omeprazole using urinary excretion data. Levofloxacin tablet and omeprazole capsule were administered separately as well as in combination in fasting condition with a wash out period of two weeks after each administration. Urine was collected at different time intervals of 0, 0-2, 2-4, 4-8, 8-12, 12-24, 24-36 and 36-48 hr post-dose and analyzed using a validated HPLC with UV detection. Different pharmacokinetic parameters for both drugs were determined using non-compartmental method. The maximum rate of excretion (R(max)) of levofloxacin was not decreased significantly when co-administered with omeprazole (p<0.05). Similarly no significant difference (p = 0.350) was observed for Rmax of omeprazole when co-administered with levofloxacin. Again the fraction of levofloxacin excreted (f(e)/f) was not changed significantly (p = 0.953) due to the co-administration of omeprazole. Similarly fraction of omeprazole excreted (f(e)/f) also remained unaffected (p = 0.672) when co-administered with levofloxacin. No significant change was observed for the area under the rate of excretion versus midpoint of time interval curve from zero to 48 hours (AURC(0-48)) for levofloxacin and omeprazole (p = 0.816 and 0.792 respectively) when administered separately and co-administered with each other. The study clearly revealed that levofloxacin and omeprazole do not undergo any kind of interactions when administered together. So it can be concluded that these two drugs can be prescribed together to achieve optimum therapeutic activity.


Assuntos
Interações Medicamentosas , Levofloxacino , Ofloxacino/farmacocinética , Ofloxacino/urina , Omeprazol/farmacocinética , Omeprazol/urina , Adolescente , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo
16.
Mol Cell Endocrinol ; 315(1-2): 159-67, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-19703515

RESUMO

The pyruvate dehydrogenase complex (PDC) catalyzes the conversion of pyruvate to acetyl-CoA in mitochondria and is a key regulatory enzyme in the oxidation of glucose to acetyl-CoA. Phosphorylation of PDC by the pyruvate dehydrogenase kinases (PDK) inhibits its activity. The expression of the pyruvate dehydrogenase kinase 4 (PDK4) gene is increased in fasting and other conditions associated with the switch from the utilization of glucose to fatty acids as an energy source. Transcription of the PDK4 gene is elevated by glucocorticoids and inhibited by insulin. In this study, we have investigated the factors involved in the regulation of the PDK4 gene by these hormones. Glucocorticoids stimulate PDK4 through two glucocorticoid receptor (GR) binding sites located more than 6000 base pairs upstream of the transcriptional start site. Insulin inhibits the glucocorticoid induction in part by causing dissociation of the GR from the promoter. Previously, we found that the estrogen related receptor alpha (ERRalpha) stimulates the expression of PDK4. Here, we determined that one of the ERRalpha binding sites contributes to the insulin inhibition of PDK4. A binding site for the forkhead transcription factor (FoxO1) is adjacent to the ERRalpha binding sites. FoxO1 participates in the glucocorticoid induction of PDK4 and the regulation of this gene by insulin. Our data demonstrate that glucocorticoids and insulin each modulate PDK4 gene expression through complex hormone response units that contain multiple factors.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Insulina/farmacologia , Isoenzimas/metabolismo , Proteínas Quinases/metabolismo , Animais , Células Cultivadas , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Genes Reporter , Glucocorticoides/metabolismo , Humanos , Insulina/metabolismo , Isoenzimas/genética , Mutagênese Sítio-Dirigida , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas Quinases/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ratos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Glucocorticoides/metabolismo , Elementos de Resposta , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Receptor ERRalfa Relacionado ao Estrogênio
17.
J Biol Chem ; 281(52): 39897-906, 2006 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-17079227

RESUMO

The pyruvate dehydrogenase complex (PDC) catalyzes the conversion of pyruvate to acetyl-CoA in mitochondria and is a key regulatory enzyme in the oxidation of glucose to acetyl-CoA. Phosphorylation of PDC by the pyruvate dehydrogenase kinases (PDK2 and PDK4) inhibits PDC activity. Expression of the PDK genes is elevated in diabetes, leading to the decreased oxidation of pyruvate to acetyl-CoA. In these studies we have investigated the transcriptional regulation of the PDK4 gene by the estrogen-related receptors (ERRalpha and ERRgamma). The ERRs are orphan nuclear receptors whose physiological roles include the induction of fatty acid oxidation in heart and muscle. Previously, we found that the peroxisome proliferator-activated receptor gamma coactivator (PGC-1alpha) stimulates the expression of PDK4. Here we report that ERRalpha and ERRgamma stimulate the PDK4 gene in hepatoma cells, suggesting a novel role for ERRs in controlling pyruvate metabolism. In addition, both ERR isoforms recruit PGC-1alpha to the PDK4 promoter. Insulin, which decreases the expression of the PDK4 gene, inhibits the induction of PDK4 by ERRalpha and ERRgamma. The forkhead transcription factor (FoxO1) binds the PDK4 gene and contributes to the induction of PDK4 by ERRs and PGC-1alpha. Insulin suppresses PDK4 expression in part through the dissociation of FoxO1 and PGC-1alpha from the PDK4 promoter. Our data demonstrate a key role for the ERRs in the induction of hepatic PDK4 gene expression.


Assuntos
Regulação Enzimológica da Expressão Gênica/fisiologia , Proteínas Quinases/biossíntese , Proteínas Quinases/genética , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores de Estrogênio/fisiologia , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Animais , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Isoenzimas/biossíntese , Isoenzimas/genética , Fígado/enzimologia , Fígado/metabolismo , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Regiões Promotoras Genéticas , Ligação Proteica/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Piruvatos/metabolismo , Proteínas de Ligação a RNA/fisiologia , Ratos , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Estrogênio/metabolismo , Fatores de Transcrição/fisiologia , Receptor ERRalfa Relacionado ao Estrogênio
18.
Protein Sci ; 14(1): 89-96, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15576567

RESUMO

The alpha-lactalbumins form stable molten globule states under a range of conditions, with the low pH form being the best characterized. The stability of the molten globule varies among different members of this family, but the origin of the stability difference is not clear. We compare the folding and stability of alpha-subdomain constructs of human and bovine alpha-lactalbumin. Previous studies have demonstrated that the isolated alpha-subdomain of human alpha-lactalbumin folds and forms a molten globule state. The minimum core construct has been defined to include the A, B, and D alpha-helices and the C-terminal 3(10) helix. A construct corresponding to the same region of bovine alpha-lactalbumin is much less structured and less stable than the human alpha-lactalbumin construct. Addition of the C-helix to generate a 75-residue bovine construct does not lead to a significant increase in structure or stability. This construct (AB-CD/3(10)) contains the entire alpha-subdomain of bovine alpha-lactalbumin. Thus molten globule formation in the human protein, but not in the bovine protein, can be rationalized on the basis of a stable alpha-subdomain. Interactions involving more of the protein chain are required to generate a well structured molten globule in the bovine protein. Comparison of AB-CD/3(10) to the molten globule formed by the intact protein and to the protein with the 6-120 disulfide reduced indicates that both the beta-subdomain and the 6-120 disulfide play a role in stabilizing the bovine alpha-lactalbumin molten globule.


Assuntos
Lactalbumina/química , Estrutura Terciária de Proteína , Subunidades Proteicas/química , Animais , Bovinos , Humanos , Dobramento de Proteína , Ureia/química
19.
Biochemistry ; 43(31): 9961-7, 2004 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-15287723

RESUMO

The alpha-lactalbumins and c-type lysozymes have virtually identical structure but exhibit very different folding behavior. All alpha-lactalbumins form a well populated molten globule state, while most of the lysozymes do not. alpha-Lactalbumin consists of two subdomains, and the alpha-subdomain is considerably more structured in the molten globule state than the beta-subdomain. Constructs derived from the alpha-subdomain of human alpha-lactalbumin containing the A, B, D, and 3(10) helices are known to form a molten globule state in the absence of the rest of the protein (Demarest, S. et al. (1999) J. Mol. Biol. 294, 213-221). Here we reported comparative studies of constructs derived from the same regions of canine and equine lysozymes. These proteins form two of the most stable molten globule states among all the lysozymes. A construct containing the A, B, D, and 3(10) helices of equine lysozyme is partially helical but is less structured than the corresponding human alpha-lactalbumin peptide. Addition of the C-helix leads to a construct that is still less structured and less stable than the alpha-lactalbumin construct. The corresponding construct from canine lysozyme is also less structured and less stable than the alpha-lactalbumin peptide. Thus, molten globule formation in human alpha-lactalbumin can be driven by the isolated alpha-subdomain, while more extensive interactions are required to generate a stable molten globule in the two lysozymes. The stability of the canine and equine lysozyme constructs is similar, indicating that the extraordinary stability of the canine lysozyme molten globule is not due to an unusually stable isolated alpha-subdomain.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Lactalbumina/química , Muramidase/metabolismo , Dobramento de Proteína , Sequência de Aminoácidos , Animais , Proteínas de Ligação ao Cálcio/síntese química , Proteínas de Ligação ao Cálcio/isolamento & purificação , Cães , Estabilidade Enzimática , Cavalos , Humanos , Lactalbumina/metabolismo , Dados de Sequência Molecular , Muramidase/síntese química , Muramidase/isolamento & purificação , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/isolamento & purificação , Desnaturação Proteica , Mapeamento de Interação de Proteínas , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Ureia
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