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1.
Br Poult Sci ; 65(3): 315-330, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38393938

RESUMO

1. Effects of cereal type and conditioning temperature (CT) on protein and carbohydrate (CHO) molecular structures, nutrient retention, carcass and blood characteristics, caecal microbial population and growth criteria of broilers fed pellet diet were evaluated for a total period of 35 d.2. In total, 336-day-old Cobb 500 broiler chicks were randomly allotted into a 2 × 2 factorial arrangement with two different cereal types (maize or wheat) processed in two different temperatures (CT; 68°C or 90°C) with seven pen replicates containing 12 birds each.3. Chicks fed the maize-based diets significantly gained higher body weight (BW) and lower feed conversion ratio (FCR) in comparison to the chicks fed wheat-based diets during the whole grow-out period (p < 0.01). Overall, the highest BW and feed intake (FI) were seen in birds fed wheat-based diets conditioned at 68°C, but the lowest FCR was observed in maize-based diet conditioned at 90°C at 7, 14 and 21 d of age (p < 0.01). However, BW was higher and FCR lower in chicks fed maize-based diets conditioned at 90°C in the grower period (28 and 35 d; p < 0.01).4. The α-helix height was higher in wheat-based starter diets in comparison to the maize-based diet (p < 0.01). Ratio of amide I to II area and total CHO peak height were increased when diets were processed at 90°C in both maize and wheat-based starter diet (p < 0.05). Increasing the CT from 68°C to 90°C reduced CHO peak 1 and 2 height by 11.6% and 3.95%, respectively, in maize-based starter diets, while increasing the CT from 68°C to 90°C reduced CHO peak 1 and 2 height by 54.3% and 57.2%, respectively, in wheat-based starter diets. In the grower diets, increasing the CT from 68°C to 90°C increased CHO peak 1 by 23% in maize-based diets, but reduced CHO peak 1 by 24.5% in wheat-based diets.5. Calcium and phosphorous retention were highest in chicks fed wheat-based diets conditioned at 90°C and lowest in chicks fed maize-based diets conditioned at 90°C (p < 0.01). Salmonella, E. coli and coliforms in the caeca reduced significantly (p < 0.05) in chicks fed wheat-based diets conditioned at 90°C on d 11 and increased with the same diet at 35 d of age compared to the chicks fed maize-based diets conditioned at both 68°C and 90°C or wheat-based diets conditioned at 68°C.6. Conditioning the wheat-based diets at 68°C improved production responses without causing any adverse effects on protein and CHO molecular structures, however increasing the conditioning temperature to 90°C impaired performance due to alteration of protein and CHO molecular structures. In contrast, conditioning of the maize-based diets at 90°C had the opposite effect, and improved production performance compared to diets conditioned at 68°C.


Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Galinhas , Dieta , Proteínas Alimentares , Triticum , Zea mays , Animais , Galinhas/crescimento & desenvolvimento , Galinhas/fisiologia , Ração Animal/análise , Dieta/veterinária , Zea mays/química , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Triticum/química , Proteínas Alimentares/metabolismo , Proteínas Alimentares/administração & dosagem , Distribuição Aleatória , Grão Comestível/química , Masculino , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Temperatura
2.
Bioinformatics ; 38(8): 2194-2201, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35179571

RESUMO

MOTIVATION: Single-cell RNA sequencing (scRNAseq) technologies allow for measurements of gene expression at a single-cell resolution. This provides researchers with a tremendous advantage for detecting heterogeneity, delineating cellular maps or identifying rare subpopulations. However, a critical complication remains: the low number of single-cell observations due to limitations by rarity of subpopulation, tissue degradation or cost. This absence of sufficient data may cause inaccuracy or irreproducibility of downstream analysis. In this work, we present Automated Cell-Type-informed Introspective Variational Autoencoder (ACTIVA): a novel framework for generating realistic synthetic data using a single-stream adversarial variational autoencoder conditioned with cell-type information. Within a single framework, ACTIVA can enlarge existing datasets and generate specific subpopulations on demand, as opposed to two separate models [such as single-cell GAN (scGAN) and conditional scGAN (cscGAN)]. Data generation and augmentation with ACTIVA can enhance scRNAseq pipelines and analysis, such as benchmarking new algorithms, studying the accuracy of classifiers and detecting marker genes. ACTIVA will facilitate analysis of smaller datasets, potentially reducing the number of patients and animals necessary in initial studies. RESULTS: We train and evaluate models on multiple public scRNAseq datasets. In comparison to GAN-based models (scGAN and cscGAN), we demonstrate that ACTIVA generates cells that are more realistic and harder for classifiers to identify as synthetic which also have better pair-wise correlation between genes. Data augmentation with ACTIVA significantly improves classification of rare subtypes (more than 45% improvement compared with not augmenting and 4% better than cscGAN) all while reducing run-time by an order of magnitude in comparison to both models. AVAILABILITY AND IMPLEMENTATION: The codes and datasets are hosted on Zenodo (https://doi.org/10.5281/zenodo.5879639). Tutorials are available at https://github.com/SindiLab/ACTIVA. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Análise de Célula Única , Análise da Expressão Gênica de Célula Única , Animais , Algoritmos , Sequenciamento do Exoma , Benchmarking
3.
Allergol Immunopathol (Madr) ; 45(6): 602-615, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28411962

RESUMO

Common variable immunodeficiency (CVID) is a diagnostic category of primary immunodeficiency (PID) which may present with heterogeneous disorders including recurrent infections, autoimmunity, granulomatous diseases, lymphoid and other types of malignancies. Generally, the incidence of malignancy in CVID patients is around 1.5-20.7% and usually occurs during the 4th-6th decade of life. Non-Hodgkin lymphoma is the most frequent malignancy, followed by epithelial tumours of stomach, breast, bladder and cervix. The exact pathological mechanisms for cancer development in CVID are not fully determined; however, several mechanisms including impaired genetic stability, genetic predisposition, immune dysregulation, impaired clearance of oncogenic viruses and bacterial infections, and iatrogenic causes have been proposed to contribute to the high susceptibility of these patients to malignancies.


Assuntos
Imunodeficiência de Variável Comum/epidemiologia , Sistema Imunitário , Neoplasias/epidemiologia , Fatores Etários , Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/fisiopatologia , Interação Gene-Ambiente , Predisposição Genética para Doença , Homeostase , Humanos , Incidência , Neoplasias/complicações , Neoplasias/fisiopatologia
4.
Br J Surg ; 103(3): 290-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26621029

RESUMO

BACKGROUND: A variety of therapeutic approaches are available for faecal incontinence. Implantation of Gatekeeper prostheses is a new promising option. The primary endpoint of this prospective observational multicentre study was to assess the clinical efficacy of Gatekeeper implantation in patients with faecal incontinence. Secondary endpoints included the assessment of patients' quality of life, and the feasibility and safety of implantation. METHODS: Patients with faecal incontinence, with either intact sphincters or internal anal sphincter lesions extending for less than 60° of the anal circumference, were selected. Intersphincteric implantation of six prostheses was performed. At baseline, and 1, 3 and 12 months after implantation, the number of faecal incontinence episodes, Cleveland Clinic Faecal Incontinence, Vaizey and American Medical Systems, Faecal Incontinence Quality of Life Scale and Short Form 36 Health Survey scores were recorded. Endoanal ultrasonography was performed at baseline and follow-up. RESULTS: Fifty-four patients were implanted. After Gatekeeper implantation, incontinence to gas, liquid and solid stool improved significantly, soiling was reduced, and ability to defer defaecation enhanced. All faecal incontinence severity scores were significantly reduced, and patients' quality of life improved. At 12 months, 30 patients (56 per cent) showed at least 75 per cent improvement in all faecal incontinence parameters, and seven (13 per cent) became fully continent. In three patients a single prosthesis was extruded during surgery, but was replaced immediately. After implantation, prosthesis dislodgement occurred in three patients; no replacement was required. CONCLUSION: Anal implantation of the Gatekeeper in patients with faecal incontinence was effective and safe. Clinical benefits were sustained at 1-year follow-up.


Assuntos
Canal Anal/cirurgia , Defecação/fisiologia , Incontinência Fecal/cirurgia , Próteses e Implantes , Implantação de Prótese/métodos , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal/fisiopatologia , Estudos de Viabilidade , Incontinência Fecal/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Desenho de Prótese , Resultado do Tratamento
5.
Cell Mol Biol (Noisy-le-grand) ; 62(2): 68-74, 2016 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-26950454

RESUMO

It has been shown that combination of imatinib (IM) with other agents may have some advantages in avoiding toxicity and resistance caused by this drug. The selective cyclooxygenase-2 inhibitor, celecoxib (CX), has been known to have antitumor and chemo-sensitizing effect in the treatment of colorectal cancer. In this study, we investigated the effectiveness of CX and its combination with anticancer agent IM on human colorectal cancer HT-29 cell and their probable molecular targets. Cultured HT-29 cells were exposed to IC50 dose of CX, IM, and their combination (half dose of IC50) for 24 hours to assess their effect on proliferation inhibition by MTT assay. The caspase-3 activity was estimated in HT-29 cells with colorimetric kit. COX-2, Caspase-3, VEGF and NF-κB genes expression was also investigated using real-time PCR method. Combined treatment with IM and CX, resulted in a significant (P˂0.05) decrease in cell viability and increased caspase-3 enzyme activity. Decreased COX-2 gene expression has been found in CX and combined treated group. Significant increase in Caspase-3 gene expression has been shown in IM and combined treated cells. In conclusion, the present in vitro study with colon cancer cell line demonstrated that CX and its combination with IM improved the anticancer activity of each component. Caspase-3 and COX-2 dependent molecular targets seem to be involved in mediating the anti-proliferative effects of IM and CX combination. Of course, the other molecular pathways are also likely to play the role and should be explored in future studies.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Celecoxib/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Células HT29 , Humanos , Mesilato de Imatinib/farmacologia , NF-kappa B/genética , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
J Anim Physiol Anim Nutr (Berl) ; 100(4): 618-22, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26459218

RESUMO

Harvesting, handling and transporting quails to the slaughterhouses, other farms and laboratories might covertly reduce their welfare. The aim of this study was to evaluate the effects of two major sources of energy in poultry nutrition on reducing transportation stress in Japanese quail (Coturnix Coturnix japonica). Male quails (n = 60) were divided into two groups. The first group was fed corn-based diet, and the second was fed wheat-based diet supplemented with xylanase and phytase. At the end of the experiment (day 35), quails were subjected to 80 km of transportation. Immediately on arrival and after 24 h, heterophil counts, lymphocyte counts and H:L ratios were measured. On arrival, H counts were lower, L counts were higher, and H:L ratios were lower for corn-fed group. After 24 h, wheat-fed group showed lower increment of H counts, greater increment of L counts and also decrement of H:L ratios rather than corn-fed group which showed increment of H:L ratios. However, these ratios were still lower in corn-fed group. Results indicate that corn-based diets can help Japanese quail to better resist transportation stress, although it seems that feeding wheat-based diets supplemented with xylanase and phytase could have positive effects for coping better with stress after journeys.


Assuntos
Ração Animal/análise , Coturnix , Estresse Fisiológico/efeitos dos fármacos , Meios de Transporte , Triticum/química , Zea mays/química , 6-Fitase/administração & dosagem , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Endo-1,4-beta-Xilanases/administração & dosagem , Masculino
7.
Biophys Rev (Melville) ; 4(1): 011306, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38505815

RESUMO

Spatial transcriptomics (ST) technologies are rapidly becoming the extension of single-cell RNA sequencing (scRNAseq), holding the potential of profiling gene expression at a single-cell resolution while maintaining cellular compositions within a tissue. Having both expression profiles and tissue organization enables researchers to better understand cellular interactions and heterogeneity, providing insight into complex biological processes that would not be possible with traditional sequencing technologies. Data generated by ST technologies are inherently noisy, high-dimensional, sparse, and multi-modal (including histological images, count matrices, etc.), thus requiring specialized computational tools for accurate and robust analysis. However, many ST studies currently utilize traditional scRNAseq tools, which are inadequate for analyzing complex ST datasets. On the other hand, many of the existing ST-specific methods are built upon traditional statistical or machine learning frameworks, which have shown to be sub-optimal in many applications due to the scale, multi-modality, and limitations of spatially resolved data (such as spatial resolution, sensitivity, and gene coverage). Given these intricacies, researchers have developed deep learning (DL)-based models to alleviate ST-specific challenges. These methods include new state-of-the-art models in alignment, spatial reconstruction, and spatial clustering, among others. However, DL models for ST analysis are nascent and remain largely underexplored. In this review, we provide an overview of existing state-of-the-art tools for analyzing spatially resolved transcriptomics while delving deeper into the DL-based approaches. We discuss the new frontiers and the open questions in this field and highlight domains in which we anticipate transformational DL applications.

8.
bioRxiv ; 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37398136

RESUMO

A limitation of current deep learning (DL) approaches for single-cell RNA sequencing (scRNAseq) analysis is the lack of interpretability. Moreover, existing pipelines are designed and trained for specific tasks used disjointly for different stages of analysis. We present scANNA, a novel interpretable DL model for scRNAseq studies that leverages neural attention to learn gene associations. After training, the learned gene importance (interpretability) is used to perform downstream analyses (e.g., global marker selection and cell-type classification) without retraining. ScANNA's performance is comparable to or better than state-of-the-art methods designed and trained for specific standard scRNAseq analyses even though scANNA was not trained for these tasks explicitly. ScANNA enables researchers to discover meaningful results without extensive prior knowledge or training separate task-specific models, saving time and enhancing scRNAseq analyses.

9.
Biomed Pharmacother ; 165: 115077, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37393865

RESUMO

Traditional bulk sequencing methods are limited to measuring the average signal in a group of cells, potentially masking heterogeneity, and rare populations. The single-cell resolution, however, enhances our understanding of complex biological systems and diseases, such as cancer, the immune system, and chronic diseases. However, the single-cell technologies generate massive amounts of data that are often high-dimensional, sparse, and complex, thus making analysis with traditional computational approaches difficult and unfeasible. To tackle these challenges, many are turning to deep learning (DL) methods as potential alternatives to the conventional machine learning (ML) algorithms for single-cell studies. DL is a branch of ML capable of extracting high-level features from raw inputs in multiple stages. Compared to traditional ML, DL models have provided significant improvements across many domains and applications. In this work, we examine DL applications in genomics, transcriptomics, spatial transcriptomics, and multi-omics integration, and address whether DL techniques will prove to be advantageous or if the single-cell omics domain poses unique challenges. Through a systematic literature review, we have found that DL has not yet revolutionized the most pressing challenges of the single-cell omics field. However, using DL models for single-cell omics has shown promising results (in many cases outperforming the previous state-of-the-art models) in data preprocessing and downstream analysis. Although developments of DL algorithms for single-cell omics have generally been gradual, recent advances reveal that DL can offer valuable resources in fast-tracking and advancing research in single-cell.


Assuntos
Aprendizado Profundo , Transcriptoma , Genômica/métodos , Aprendizado de Máquina , Perfilação da Expressão Gênica
11.
Pediatr Surg Int ; 26(10): 967-70, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20632018

RESUMO

BACKGROUND: Hirschsprung's disease (HD) is a relatively common congenital disease that could be suspected by clinical symptoms, abdominal plain X-ray, and finally diagnosed by rectal biopsy. In 80% cases, rectosigmoid junction is involved. Recently, one-stage transanal pull-through (TAPT) procedure has been popular and may have several complications. METHODS AND PATIENTS: During a 4-year period, 86 infants (28 girls, 58 boys) with mean age 8 days (3-33) and clinically suspected to HD were admitted in our center. HD was proved by rectal biopsy. All patients after full bowel preparation and rectal washout were candidates for TAPT operation. A Swenson-like procedure was performed and the anastomosis was done between the well blood supply ganglionic colon and the rectum at 1 cm above dentate line. Interrupted suture with 5-0 Vicryl was used. Nelaton tube (12 F) inserted in the pelvis via transprineal for drainage of blood or collection. From February 2008 in 30 cases, prophylactic Hegar dilatation was performed 2 weeks after operation. RESULTS: Anal stricture in 12 cases (14%) was treated by anal dilation in 10 cases and 2 cases corrected by surgical management. Entrocolitis in 4 cases (5%) was treated by medical management. In two cases, retrocolic abscess had spontaneous drainage via tube drain. There was no anastomotic stricture after starting prophylactic anal bouginage. CONCLUSION: TAPT has many advantages, low complications and the results are excellent. It seems the most common complication is anastomotic stricture that responds well to prophylactic bouginage. We recommend prophylactic anal bouginage with Hegar probe at 2 weeks after operation. Long-term follow-up is needed to evaluate the outcomes of our operations.


Assuntos
Canal Anal/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Dilatação/métodos , Doença de Hirschsprung/cirurgia , Canal Anal/patologia , Biópsia , Colo Sigmoide/cirurgia , Feminino , Seguimentos , Doença de Hirschsprung/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Radiografia Abdominal , Estudos Retrospectivos , Resultado do Tratamento
12.
J Mol Model ; 26(6): 164, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32494890

RESUMO

Tetrachlorodibenzodioxin (TCDD) is one of the most famous dioxin families that is hazardous to humans and the environment. Designing cheap and novel catalysts for its detecting and removing is an essential need for the environment. In this work, DFT + VdW is used to investigate the potentiality of proposed catalysts in adsorbing and dissociating TCDD. P-type and N-type charge carrier effects on the adsorption process are modeled by doping of B/Al and N/P atoms in the graphene. Al-doped graphene, with - 1.27 eV adsorption energy, has the highest possibility to adsorb TCDD. P-type dopants have higher interactions with TCDD in comparing with N-type dopants. Introducing positive and negative charges on the studied complexes shows that in all complexes, the driving force of complexation is π-π stacking except for the Al-doped graphene. Dissociative adsorption studies show that unlike literature data, chlorine atoms on the surface of studied catalysts are not dissociated from TCDD, and instead, C-O bonds in TCDD are dissociated symmetrically and asymmetrically. Data show that Al-doped graphene is the best catalyst for symmetrical dissociation, and pure graphene is the best one for asymmetrical dissociation of TCDD.

13.
Int J Organ Transplant Med ; 11(3): 129-142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913589

RESUMO

BACKGROUND: In care of brain-dead patients, nurses face several challenges. It is important to determine the context behind these challenges since they affect the performance of nurses and the organ donation process. OBJECTIVE: To identify factors affecting the emergence of challenges related to the management of brain-dead patients by nurses in the donation process. METHODS: In this qualitative conventional content analysis, data were collected by performing 28 semi-structured and in-depth interviews with nurses working in the ICUs. Purposive sampling started from March 2014 until saturation, which was reached in June 2016. Data analysis occurred simultaneously with data collection. RESULTS: Qualitative analysis of contents provided from interviews led to the extraction of themes that showed the experience of nurses about the challenges of caring for brain-dead patients in the donation process. These themes included "doubt and conflict in accepting the situation" and "defects in an effective and targeted care system." In the end, the main theme of "inconsistency and incompatibility of care management" was abstracted. CONCLUSION: According to the results of the study, factors involved in the emergence of challenges for nurses in care management included defects in education or managerial problems, which increased tension for nurses.

14.
Mol Cell Biol ; 13(5): 2909-18, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-7682654

RESUMO

Because heat shock proteins have been shown to play a critical role in protecting cells from hyperthermia and other types of physiological stresses, it was of interest to determine what effect age and caloric restriction have on the ability of cells to regulate the expression of heat shock protein 70 (hsp70), the most prominent and most evolutionarily conserved of the heat shock proteins. Caloric restriction is the only experimental manipulation known to retard aging and increase survival of mammals. The ability of hepatocytes isolated from young/adult (4- to 7-month-old) and old (22- to 28-month-old) male Fischer F344 rats fed ad libitum or a caloric restriction diet (60% of the content of the ad libitum diet) to express hsp70 was determined after a mild heat shock (42.5 degrees C for 30 min). We found that the induction of hsp70 synthesis and mRNA levels by heat shock was 40 to 50% lower in hepatocytes isolated from old rats than in hepatocytes isolated from young rats. Using in situ hybridization, we found that essentially all hepatocytes from the young/adult and old rats expressed hsp70 in response to heat shock; therefore, the age-related decrease in the induction of hsp70 expression was not due to an age-related accumulation of cells that do not respond to heat shock. Measurements of hsp70 mRNA stability and hsp70 transcription demonstrated that the age-related decline in hsp70 expression arose from a decline in hsp70 transcription. Interestingly, the age-related decline in the induction of hsp70 expression was reversed by caloric restriction; e.g., the induction of hsp70 synthesis, mRNA levels, and nuclear transcription were significantly higher in hepatocytes isolated from old rats fed the caloric restricted diet than in hepatocytes isolated from old rats fed ad libitum. The levels of the heat shock transcription factor in nuclear extracts isolated from heat-shocked hepatocytes were measured in a gel shift assay. Binding of the heat shock transcription factor to the heat shock element decreased with age and was significantly higher in hepatocyte extracts isolated from old rats fed the caloric restriction diet than in those from old rats fed ad libitum. Thus, our study demonstrates that the ability of hepatocytes to respond to hyperthermia and express hsp70 decreases significantly with age and that this decrease occurs at the transcriptional level. In addition, caloric restriction, which retards aging, reversed the age-related decline in the induction of hsp70 transcription in hepatocytes.


Assuntos
Envelhecimento/genética , Dieta Redutora , Proteínas de Choque Térmico/biossíntese , Fígado/fisiologia , RNA Mensageiro/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Northern Blotting , Núcleo Celular/fisiologia , Células Cultivadas , Eletroforese em Gel Bidimensional , Proteínas de Choque Térmico/análise , Proteínas de Choque Térmico/genética , Hibridização In Situ , Cinética , Masculino , Dados de Sequência Molecular , Peso Molecular , Oligodesoxirribonucleotídeos , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos F344
15.
Mech Ageing Dev ; 50(3): 227-48, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2561003

RESUMO

The qualitative and quantitative changes in the phosphorylation of specific proteins in hepatocyte suspension from 5-, 12- and 22-month-old male Fischer F344 rats were analyzed by two-dimensional polyacrylamide gel electrophoresis. No qualitative changes in phosphorylation of individual proteins were observed with age. In addition, very few quantitative changes (less than 2% of proteins studied) in protein phosphorylation were detected. The phosphorylation of two acidic proteins decreased (50%) with age while the phosphorylation of one basic protein increased (300%) with age. The two acidic proteins and one basic protein that showed quantitative changes with age were found predominately in the microsome and nuclear fractions of hepatocytes, respectively. The effect of dietary restriction on the phosphorylation of proteins in male Fischer F344 rats was also studied. Although, dietary restriction alters the age-related incident of disease and prolongs longevity, it did not have any significant effect on phosphorylation of individual proteins in the liver.


Assuntos
Envelhecimento/metabolismo , Fígado/metabolismo , Proteínas/metabolismo , Animais , Dieta , Eletroforese em Gel de Poliacrilamida , Masculino , Fosfoproteínas Fosfatases/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Quinases/metabolismo , Ratos , Ratos Endogâmicos F344
16.
Mech Ageing Dev ; 107(3): 255-70, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10360681

RESUMO

A decline in the induction of heat shock protein 70 (hsp70) expression with age has been shown to occur in a variety of tissues from male rodents. Because the age-related change in the expression of many genes often differ in male and female rodents, we have measured the induction of hsp70 expression in hepatocytes and splenocytes from young/adult (4-8 months) and old (20-22 months) female Fischer 344 rats. Hepatocytes and splenocytes isolated from old female rats showed a marked decrease in the induction of hsp70 mRNA and protein levels by heat shock when compared to hepatocytes and splenocytes isolated from young/adult female rats. Because the heat shock transcription factor HSF1 mediates the heat-induced transcription of hsp70, the effect of age on HSF1 was also studied. The ability of extracts from heat-shocked splenocytes to bind to the heat shock element (HSE) decreased with age. Interestingly, the levels of HSF1 protein were similar in splenocytes and hepatocytes from old female rats compared to young/adult female rats, even though the levels of HSE-binding were lower for splenocytes isolated from old rats. In this study, we show an age-related decline in the expression of hsp70, and this decline was similar to what we had previously observed in male Fischer 344 rats.


Assuntos
Envelhecimento/metabolismo , Proteínas de Choque Térmico HSP70/biossíntese , Fígado/metabolismo , Baço/metabolismo , Animais , Feminino , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Fígado/citologia , Ratos , Ratos Endogâmicos F344 , Baço/citologia
17.
Transplantation ; 51(2): 316-20, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1994522

RESUMO

We compared our standard NIH (extended incubation) crossmatch (XM) with antihuman globulin (AHG) and flow cytometry crossmatches (FCXM) and correlated the results with primary cadaveric and retransplant graft survivals. In addition, we treated the XM sera with the reducing reagent dithioerythritol (DTE) to discriminate IgM from IgG immunoglobulin reactivity. For the 166 CsA-Pred-treated primary cadaveric renal allograft recipients the 1-year graft survival rate following an NIH-NEG XM was 81%. NIH-XM-NEG recipients who were also AHG-XM-NEG displayed an 82% 1-year graft survival as well. In contrast, NIH-NEG, but AHG-POS XM primary CAD recipients displayed a significantly reduced graft survival rate of 67%. Treatment of AHG-POS XM sera with DTE-delineated DTE/AHG-NEG and POS crossmatches associated with significantly different graft survivals of 83% and 0%, respectively, for these primary recipients. Flow cytometry XM results did not improve on the AHG-NEG or DTE/AHG-NEG XM primary graft survivals. These results were seen whether testing pre-Tx or historical (Hx) sera. For Re-Tx recipients an AHG-NEG XM resulted in significantly improved graft survival compared with the NIH-XM-NEG results. The overall 1-year graft survival rate for the 70 Re-Tx recipients studied was 64% (following a NEG pre-Tx NIH-XM). Re-Tx recipients with an AHG-NEG XM displayed an improved graft survival compared with NIH-XM-NEG recipients (77% vs. 64%, P less than 0.05) and with AHG-POS recipients (77% vs. 36%, P less than 0.01). However, treatment of Re-Tx, AHG-POS sera with DTE resulted in comparably poor graft survival rates of 31% and 50% for DTE/AHG-NEG and POS crossmatches, respectively. A FCXM did not improve on the results of Re-Tx graft survival following an AHG-NEG XM. These results were obtained whether testing pre-Tx or Hx sera. HLA matching, PRA, and the time the first Tx was lost did not influence the Re-Tx graft survival outcome following an AHG-NEG XM. Therefore, successful primary cadaveric renal allograft survival can be accomplished following either an AHG-NEG XM or an AHG-DTE-NEG XM. Re-Tx graft survival is significantly improved following an AHG-NEG XM. Re-Tx recipients with an AHG-POS XM who are either DTE/AHG-POS or -NEG display reduced graft survivals compared with AHG-NEG Re-Tx recipients.


Assuntos
Sobrevivência de Enxerto , Teste de Histocompatibilidade/métodos , Transplante de Rim/imunologia , Ciclosporinas/uso terapêutico , Citotoxicidade Imunológica , Ditioeritritol/farmacologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Isoanticorpos/análise , Linfócitos/imunologia , Prednisolona/uso terapêutico
18.
Transplantation ; 53(1): 64-7, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1733088

RESUMO

Data from the Office of the Inspector General and the United Network for Organ Sharing suggested that black end-stage renal disease patients had unequal access to organ transplantation, in that they waited twice as long as white ESRD patients for a renal transplant. We hypothesized that preTx histocompatibility factors were more influential in determining how quickly an ESRD patient was transplanted than had been realized by either the Office of the Inspector General or UNOS. To test this hypothesis we compared the crossmatch reactivity of 378 white and 227 black ESRD patients awaiting a primary renal Tx against 100 consecutive cadaveric donors (80 white, 10 black, and 10 Mexican-American). A positive XM frequency of 16% (179 positive XM/1121 total XM) was observed when white ESRD patients were crossmatched against white donors. A comparable frequency of 21% (39/186) (+) XM was observed when white ESRD patients were crossmatched against black donors. Similarly, black ESRD patients crossmatched against black donors showed a 17% (20/115) (+) XM frequency. In contrast, a significantly higher (+) XM frequency of 43% (283/655) was observed when black ESRD patients were crossmatched against white donors (P less than 0.001). When black ESRD patients with a (+) preTx blood transfusion history were crossmatched against white donors, a 55% (241/438) (+) XM frequency was observed. This (+) XM frequency was 3.2 times greater than when black ESRD patients were matched against black donors (P less than 0.001). However, when untransfused black ESRD patients were matched against white donors only a 19% (42/217) (+) XM frequency was observed. Finally, preoperatively transfused black ESRD patients displayed a higher PRA of 47 +/- 12% vs. 27 +/- 10%, P less than 0.01, and a longer median waiting time to transplant of 329 vs. 181 days, P less than 0.01, than comparable white patients. The data suggest that presentization of blacks, following preTx blood transfusions from nonblack donors, predisposes black ESRD patients to present as immunologically inappropriate recipients for predominantly white donor allografts and results in their spending a longer time on renal transplant waiting lists.


Assuntos
Teste de Histocompatibilidade , Transplante de Rim , População Negra , Transfusão de Sangue , Cadáver , Antígenos HLA/análise , Humanos , Falência Renal Crônica/imunologia , Americanos Mexicanos , Transplante Homólogo , População Branca
19.
Immunol Lett ; 30(3): 333-7, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1800319

RESUMO

The effect of the growth state of a cell on the ability of hyperthermia to induce the synthesis of heat shock proteins (HSPs) was studied in resting and concanavalin A (ConA)-stimulated lymphocytes. Hyperthermia induced the synthesis of hsp 110, hsp 90, hsc 70, and hsp 70 in both resting and ConA-stimulated lymphocytes, and ConA-treatment induced the synthesis of the hsp 90 and hsc 70 at normal temperature. The induction of the synthesis of hsp 110 and hsp 70 by hyperthermia was 3- to 6-fold higher for lymphocytes cultured with ConA for 12 and 24 h than in non-stimulated lymphocytes. Thus, lymphocytes induced to undergo proliferation showed a greater response to hyperthermia than resting lymphocytes.


Assuntos
Concanavalina A/farmacologia , Proteínas de Choque Térmico/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Animais , Temperatura Alta , Masculino , Ratos , Ratos Endogâmicos F344 , Estimulação Química , Linfócitos T/metabolismo
20.
J Gerontol A Biol Sci Med Sci ; 53(3): B168-72, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9597039

RESUMO

Previous studies have shown that epithelial cell production rates are increased throughout the gastrointestinal tract in aging rats. We tested the hypothesis that alteration in cell death (apoptosis) might be involved. Fischer 344 rats aged 4-5 months and 24-25 months fed ad libitum (AL) or calorie restricted (CR) to 60% of the AL intake were studied. Epithelial cell apoptosis was determined by a terminal deoxyuridine nucleotidyl nick end labeling (TUNEL) technique validated in our laboratory, and the expression of four members of the Bcl-2 family was evaluated by Western blotting in the small intestine and colon. The apoptotic index was low in young and aging AL and young CR rats. However, CR in aging rats was associated with a significantly higher apoptotic index in the jejunum and colon. The expression of the Bcl-2 family of genes was unchanged. Enhanced apoptosis in CR may protect the gastrointestinal tract from accumulation of DNA-altered cells during the aging process.


Assuntos
Envelhecimento/fisiologia , Apoptose/fisiologia , Colo/crescimento & desenvolvimento , Privação de Alimentos , Mucosa Intestinal/fisiologia , Jejuno/crescimento & desenvolvimento , Animais , Ingestão de Energia , Mucosa Intestinal/citologia , Mucosa Intestinal/crescimento & desenvolvimento , Masculino , Proteínas de Membrana/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Ratos , Ratos Endogâmicos F344 , Reprodutibilidade dos Testes , Proteína Killer-Antagonista Homóloga a bcl-2 , Proteína X Associada a bcl-2 , Proteína bcl-X
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