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1.
Braz. j. med. biol. res ; 54(6): e10293, 2021. tab, graf
Article in English | LILACS | ID: biblio-1249308

ABSTRACT

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).


Subject(s)
Animals , Rats , Low-Level Light Therapy , Laser Therapy , Wound Healing , Rats, Wistar , Oxidative Stress
2.
Braz. j. med. biol. res ; 51(9): e7552, 2018. tab, graf
Article in English | LILACS | ID: biblio-951753

ABSTRACT

Guarana (Paullinia cupana) is habitually ingested by people in the Amazon region and is a key ingredient in various energy drinks consumed worldwide. Extension in longevity and low prevalence of chronic age-related diseases have been associated to habitual intake of guarana. Anti-aging potential of guarana was also demonstrated in Caenorhabditis elegans; however, the mechanisms involved in its effects are not clear. Herein, we investigated the putative pathways that regulate the effects of guarana ethanolic extract (GEE) on lifespan using C. elegans. The major known longevity pathways were analyzed through mutant worms and RT-qPCR assay (DAF-2, DAF-16, SKN-1, SIR-2.1, HSF-1). The possible involvement of purinergic signaling was also investigated. This study demonstrated that GEE acts through antioxidant activity, DAF-16, HSF-1, and SKN-1 pathways, and human adenosine receptor ortholog (ADOR-1) to extend lifespan. GEE also downregulated skn-1, daf-16, sir-2.1 and hsp-16.2 in 9-day-old C. elegans, which might reflect less need to activate these protective genes due to direct antioxidant effects. Our results contribute to the comprehension of guarana effects in vivo, which might be helpful to prevent or treat aging-associated disorders, and also suggest purinergic signaling as a plausible therapeutic target for longevity studies.


Subject(s)
Animals , Plant Extracts/pharmacology , Caenorhabditis elegans/drug effects , Paullinia/chemistry , Antioxidants/pharmacology , Time Factors , Aging/drug effects , Caenorhabditis elegans/physiology , Reverse Transcriptase Polymerase Chain Reaction , Longevity/drug effects , Antioxidants/isolation & purification
3.
Braz. j. med. biol. res ; 51(11): e7702, 2018. graf
Article in English | LILACS | ID: biblio-951726

ABSTRACT

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.


Subject(s)
Animals , Male , Rabbits , Physical Conditioning, Animal/adverse effects , Physical Conditioning, Animal/physiology , Cryotherapy/methods , Muscle, Skeletal/physiopathology , Muscle, Skeletal/injuries , Immersion/physiopathology , Acetylcholinesterase/analysis , Swimming/injuries , Thiazoles , Time Factors , Cell Survival/physiology , Reproducibility of Results , Reactive Oxygen Species/analysis , Cold Temperature , Fluoresceins/analysis , Myositis/prevention & control , Antioxidants/analysis
4.
Pathobiology ; 83(6): 316-326, 2016.
Article in English | LILACS, SES-SP | ID: biblio-1024773

ABSTRACT

Background: ADAMTS are metalloproteases with disintegrin and thrombospondin motifs. They are secreted proteases playing a role in biological processes such as inflammation, angiogenesis, and urogenital development. ADAMTS have specific substrates, such as the proteoglycans (PG) versican, aggrecan, and brevican. Despite data indicating a role of ADAMTS in tumor invasion and metastases, effects played by these molecules in cancer progression are still controversial. In ovarian cancer, the importance of ADAMTS gene mutations was recently described and related to chemotherapy outcome. Objective: To analyze protein levels of ADAMTS-1, -4, and -5, and TIMP-3 in human ovarian cancer classified as benign, borderline, or malignant. We also assessed the expression of the ADAMTS substrates aggrecan, brevican, and versican in these neoplasms. Correlations between overall survival and protein expression were performed. Methods: Tumors were classified according to the WHO Classification of Tumors of Female Reproductive Organs. Protein and PG expression was studied by immunohistochemistry. Differences in labeling were analyzed by percent measurements of stained areas. Results: ADAMTS-1, ADAMTS-5, and its tissue inhibitor TIMP-3 are increased in borderline and malignant tumors compared to benign neoplasms. Aggrecan and versican levels were increased in malignant subtypes compared to benign ovarian cancer. Higher ADAMTS-1, TIMP-3, and versican expression was associated with a shorter overall survival. Conclusions: Comparison of protease, TIMP-3, and substrate expression showed that in malignant tumors all ADAMTS and TIMP-3 expression levels were significantly raised compared to the substrates studied.


Subject(s)
Ovarian Neoplasms , Humans , Biomarkers, Tumor/metabolism , Gene Expression Regulation, Neoplastic , Neoplasms, Glandular and Epithelial/diagnosis , Tissue Inhibitor of Metalloproteinase-3/metabolism , ADAMTS1 Protein/metabolism , ADAMTS4 Protein/metabolism , Carcinoma, Ovarian Epithelial
5.
Braz. j. med. biol. res ; 49(9): e5235, 2016. tab, graf
Article in English | LILACS | ID: lil-788945

ABSTRACT

Improving overall health and quality of life, preventing diseases and increasing life expectancy are key concerns in the field of public health. The search for antioxidants that can inhibit oxidative damage in cells has received a lot of attention. Rosmarinus officinalis L. represents an exceptionally rich source of bioactive compounds with pharmacological properties. In the present study, we explored the effects of the ethanolic extract of R. officinalis (eeRo) on stress resistance and longevity using the non-parasitic nematode Caenorhabditis elegans as a model. We report for the first time that eeRo increased resistance against oxidative and thermal stress and extended C. elegans longevity in an insulin/IGF signaling pathway-dependent manner. These data emphasize the eeRo beneficial effects on C. elegans under stress.


Subject(s)
Animals , Caenorhabditis elegans/drug effects , Longevity/drug effects , Oxidative Stress/drug effects , Rosmarinus/chemistry , Stress, Physiological/drug effects , Caenorhabditis elegans Proteins/drug effects , DNA-Binding Proteins/drug effects , Forkhead Transcription Factors/drug effects , Signal Transduction/drug effects , Transcription Factors/drug effects
6.
Braz. j. med. biol. res ; 48(11): 1039-1047, Nov. 2015. tab, graf
Article in English | LILACS | ID: lil-762910

ABSTRACT

We collected a series of 136 lung/bronchial and 56 matched lung parenchyma tissue samples from patients who underwent lung/bronchial biopsies and presented invasive carcinoma after lung surgery. The lung/bronchial samples included basal cell hyperplasia, squamous metaplasia, moderate dysplasia, adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma and adenocarcinoma. Matched lung parenchyma tissue samples included 25 squamous cell carcinomas and 31 adenocarcinomas. Immunohistochemistry was performed to analyze for the distribution of hyaluronidase (Hyal)-1 and −3, and hyaluronan synthases (HAS)-1, −2, and −3. Hyal-1 showed significantly higher expression in basal cell hyperplasia than in moderate dysplasia (P=0.01), atypical adenomatous hyperplasia (P=0.0001), or severe dysplasia (P=0.03). Lower expression of Hyal-3 was found in atypical adenomatous hyperplasia than in basal cell hyperplasia (P=0.01) or moderate dysplasia (P=0.02). HAS-2 was significantly higher in severe dysplasia (P=0.002) and in squamous metaplasia (P=0.04) compared with basal cell hyperplasia. HAS-3 was significantly expressed in basal cell hyperplasia compared with atypical adenomatous hyperplasia (P=0.05) and severe dysplasia (P=0.02). Lower expression of HAS-3 was found in severe dysplasia compared with squamous metaplasia (P=0.01) and moderate dysplasia (P=0.01). Epithelial Hyal-1 and −3 and HAS-1, −2, and −3 expressions were significantly higher in pre-neoplastic lesions than in neoplastic lesions. Comparative Cox multivariate analysis controlled by N stage and histologic tumor type showed that patients with high HAS-3 expression in pre-neoplastic cells obtained by lung/bronchial biopsy presented a significantly higher risk of death (HR=1.19; P=0.04). We concluded that localization of Hyal and HAS in lung/bronchial pre-neoplastic and neoplastic lesions was inversely related to malignancy, which implied that visualizing these factors could be a useful diagnostic procedure for suspected lung cancer. Finalizing this conclusion will require a wider study in a randomized and prospective trial.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Bronchial Neoplasms/enzymology , Carcinoma, Squamous Cell/enzymology , Glucuronosyltransferase/metabolism , Hyaluronoglucosaminidase/metabolism , Lung Neoplasms/enzymology , Neoplasm Proteins/metabolism , Precancerous Conditions/enzymology , Bronchial Neoplasms/pathology , Carcinoma, Squamous Cell/pathology , Cell Adhesion Molecules/analysis , Hyaluronoglucosaminidase/analysis , Hyperplasia/enzymology , Immunohistochemistry , Kaplan-Meier Estimate , Lung Neoplasms/pathology , Multivariate Analysis , Metaplasia/enzymology , Prognosis , Precancerous Conditions/pathology , Severity of Illness Index , Statistics, Nonparametric
7.
Arq. bras. med. vet. zootec ; 65(4): 955-960, Aug. 2013. ilus, tab
Article in Portuguese | LILACS | ID: lil-684447

ABSTRACT

As dimensões e o peso testicular foram avaliados em 25 machos adultos de codornas japonesas (Coturnix coturnix japonica) e correlacionados entre si, a fim de se buscar obter informações que possibilitem a criação de um parâmetro preditivo da capacidade de produção espermática. As aves foram abatidas e os testículos removidos para mensuração e pesagem. As dimensões e o peso entre os testículos esquerdo e direito foram comparados. Os parâmetros testiculares foram correlacionados entre si por meio da determinação do coeficiente de correlação linear. O índice gonadossomático também foi determinado, indicando alocação de 3,68% do peso corporal em testículos nos machos avaliados, resultado maior do que os descritos na literatura. Apesar da diferença de formato entre os testículos esquerdo e direito, o peso foi semelhante, sugerindo que não há diferença na capacidade de produção espermática entre eles. Diferença estatística entre os valores biométricos indica que o testículo esquerdo é mais curto e mais arredondado, enquanto o direito é mais longo e estreito. O peso corporal apresentou baixa correlação com o peso testicular, 0,14 e 0,12 para os testículos esquerdo e direito, respectivamente. Os parâmetros que melhor se correlacionaram com o peso testicular foram a largura e a espessura. Considerando-se a identificação de um parâmetro único para comparação entre machos, a espessura do testículo esquerdo apresentou coeficiente de correlação linear de 0,89 com o somatório do peso dos dois testículos. Com base nessa informação, métodos não invasivos, como a ultrassonografia, poderiam ser utilizados para estimar o potencial reprodutivo e auxiliar na comparação de machos de codornas japonesas em núcleos de seleção de aves elite, contribuindo para melhoramento genético da espécie.


The size and testis weight were evaluated and correlated in 25 adult male Japanese quail (Coturnix coturnix japonica), seeking information to enable the development of a predictive parameter of sperm production capacity. The birds were slaughtered and testes removed for measuring and weighing. The size and testis weight were compared between the left and right. The testicular parameters were correlated by determining the linear correlation coefficient. The gonadosomatic index was also determined, indicating the allocation of 3.68% of body weight in the testes, greater than described in literature. Despite the difference in shape between the left and right testis, weight was similar, suggesting that there is no difference in the capacity of sperm production amongst them. A statistical difference between the biometric values indicates that the left testicle is shorter and more rounded, while the right is longer and narrower. Body weight showed a low correlation with the testicular weight, 0.14 and 0.12 for the left and right testes, respectively. The parameters that best correlated with testicular weight were the width and thickness. Given the identification of a single parameter for comparison of males, the thickness of the left testis showed linear correlation coefficient of 0.89 with the sum of the weight of both testicles. From this information, noninvasive methods such as ultrasound could be used to estimate the reproductive potential and ease the comparison of male Japanese quail in elite selection nuclei, contributing to the genetic improvement of the species.


Subject(s)
Animals , Coturnix/classification , Testis/anatomy & histology , Birds/classification
8.
Braz. j. med. biol. res ; 46(1): 21-31, 11/jan. 2013. tab, graf
Article in English | LILACS | ID: lil-665792

ABSTRACT

Among the most common features of highly invasive tumors, such as lung adenocarcinomas (AD) and squamous cell carcinomas (SqCC), is the massive degradation of the extracellular matrix. The remarkable qualitative and quantitative modifications of hyaluronidases (HAases), hyaluronan synthases (HAS), E-cadherin adhesion molecules, and the transforming growth factor β (TGF-β) may favor invasion, cellular motility, and proliferation. We examined HAase proteins (Hyal), HAS, E-cadherin, and TGF-β profiles in lung AD subtypes and SqCC obtained from smokers and non-smokers. Fifty-six patients, median age 64 years, who underwent lobectomy for AD (N = 31) and SqCC (N = 25) were included in the study. HAS-1, -2 and -3, and Hyal-1 and -3 were significantly more expressed by tumor cells than normal and stroma cells (P < 0.01). When stratified according to histologic types, HAS-3 and Hyal-1 immunoreactivity was significantly increased in tumor cells of AD (P = 0.01) and stroma of SqCC (P = 0.002), respectively. Tobacco history in patients with AD was significantly associated with increased HAS-3 immunoreactivity in tumor cells (P < 0.01). Stroma cells of SqCC from non-smokers presented a significant association with HAS-3 (P < 0.01). Hyal, HAS, E-cadherin, and TGF-β modulate a different tumor-induced invasive pathway in lung AD subgroups and SqCC. HAases in resected AD and SqCC were strongly related to the prognosis. Therefore, our findings suggest that strategies aimed at preventing high HAS-3 and Hyal-1 synthesis, or local responses to low TGF-β and E-cadherin, may have a greater impact in lung cancer prognosis.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Adenocarcinoma/pathology , Carcinoma, Squamous Cell/pathology , Extracellular Matrix/pathology , Lung Neoplasms/pathology , Adenocarcinoma/metabolism , Adenocarcinoma/physiopathology , Cadherins/analysis , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/physiopathology , Cell Adhesion Molecules/analysis , Extracellular Matrix/metabolism , Glucuronosyltransferase/analysis , Lung Neoplasms/metabolism , Lung Neoplasms/physiopathology , Neoplasm Staging , Neoplasm Invasiveness/prevention & control
9.
Braz. j. med. biol. res ; 45(12): 1327-1333, Dec. 2012. ilus, tab
Article in English | LILACS | ID: lil-659632

ABSTRACT

CDKN2A encodes proteins such as p16 (INK4a), which negatively regulate the cell-cycle. Molecular genetic studies have revealed that deletions in CDKN2A occur frequently in cancer. Although p16 (INK4a) may be involved in tumor progression, the clinical impact and prognostic implications in head and neck squamous cell carcinoma (HNSCC) are controversial. The objective of this study was to evaluate the frequency of the immunohistochemical expression of p16 (INK4a) in 40 oropharynx and 35 larynx from HNSCC patients treated in a single institution and followed-up at least for 10 years in order to explore potential associations with clinicopathological outcomes and prognostic implications. Forty cases (53.3%) were positive for p16 (INK4a) and this expression was more intense in non-smoking patients (P = 0.050), whose tumors showed negative vascular embolization (P = 0.018), negative lymphatic permeation (P = 0.002), and clear surgical margins (P = 0.050). Importantly, on the basis of negative p16 (INK4a) expression, it was possible to predict a probability of lower survival (P = 0.055) as well as tumors presenting lymph node metastasis (P = 0.050) and capsular rupture (P = 0.0010). Furthermore, increased risk of recurrence was observed in tumors presenting capsular rupture (P = 0.0083). Taken together, the alteration in p16 (INK4a) appears to be a common event in patients with oropharynx and larynx squamous cell carcinoma and the negative expression of this protein correlated with poor prognosis.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carcinoma, Squamous Cell/metabolism , /metabolism , Laryngeal Neoplasms/metabolism , Oropharyngeal Neoplasms/metabolism , Biomarkers, Tumor/metabolism , Disease Progression , Immunohistochemistry , Prognosis , Retrospective Studies , Survival Analysis
10.
Arq. bras. med. vet. zootec ; 63(3): 761-764, June 2011.
Article in Portuguese | LILACS | ID: lil-595598

ABSTRACT

A seven month old female goat showed neck swelling, apathy, appetite and weight loss, restlessness, increased salivation, cough, and regurgitation episodes which occurred post feeding. The animal was evaluated through both clinical and radiographic examinations. Plain radiography was performed and contrasted X-ray was done using barium sulfate. For radiological examination, the lateral projection was used for analysis. The results showed a radiopaque content in the esophageal lumen dorsally positioned to heart with density and appearance similar to the rumen. A dilation of the esophagus was reported and a diagnosis of megaesophagus was made. In conclusion, contrast esophagography must be included in the diagnosis of megaesophagus in goats.


Subject(s)
Animals , Esophagus/anatomy & histology , Esophagus/abnormalities , Esophagus/innervation , Esophagoscopy/veterinary , Esophageal Diseases/diagnosis , Esophageal Diseases/veterinary
11.
Braz. j. med. biol. res ; 43(6): 593-599, June 2010. tab
Article in English | LILACS | ID: lil-548272

ABSTRACT

Sentinel lymph node biopsy (SLNB) is an appropriate method for the evaluation of axillary status in cases of early breast cancer. We report our experience in treating cases evaluated using SLNB. We analyzed a total of 1192 cases assessed by means of SLNB from July 1999 to December 2007. SLNB processing was successfully completed in 1154 cases with the use of blue dye or radiolabeled 99mTc-Dextran-500, or both. Of these 1154 patients, 857 were N0(i-) (no regional lymph node metastasis, negative immunohistochemistry, IHC), 96 were N0(i+) (no regional lymph node metastasis histologically, positive IHC, no IHC cluster greater than 0.2 mm) and 201 were N1mi (greater than 0.2 mm, none greater than 2.0 mm). Most of the tumors (70 percent) were invasive ductal carcinomas and tumors were staged as T1 in 770 patients (65 percent). A total of 274 patients underwent SLNB and axillary dissections up to April 2003. The inclusion criteria were tumor size equal to or less than 3 cm in diameter, no clinically palpable axillary lymph nodes, no neoadjuvant therapy. In 19 cases, the SLN could not be identified intraoperatively. A false-negative rate of 11 percent and a negative predictive value of 88.2 percent were obtained for the 255 assessable patients. The overall concordance between SLNB and axillary lymph node status was 92 percent. SLNB sensitivity for nodes was 81 percent and specificity was 100 percent. The higher sensitivity, specificity, accuracy, and lower false-negative rates of SLNB suggest that this method may be an appropriate alternative to total axillary dissection in early breast cancer patients.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Young Adult , Breast Neoplasms/pathology , Sentinel Lymph Node Biopsy , Breast Neoplasms/surgery , Lymph Node Excision , Lymphatic Metastasis/pathology , Neoplasm Staging , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity , Young Adult
12.
Braz. j. med. biol. res ; 40(8): 1045-1053, Aug. 2007. ilus, tab
Article in English | LILACS | ID: lil-456808

ABSTRACT

Malignancy of pulmonary large cell carcinomas (LCC) increases from classic LCC through LCC with neuroendocrine morphology (LCCNM) to large cell neuroendocrine carcinomas (LCNEC). However, the histological classification has sometimes proved to be difficult. Because the malignancy of LCC is highly dependent on proteins with functions in the cell cycle, DNA repair, and apoptosis, p53 has been targeted as a potentially useful biological marker. p53 mutations in lung cancers have been shown to result in expression and protein expression also occurs in the absence of mutations. To validate the importance of both p53 protein expression (by immunostaining) and p53 gene mutations in lung LCC (by PCR-single strand conformational polymorphism analysis of exons 5, 6, 7, and 8) and to study their relationships with clinical factors and sub-classification we investigated the correlation of p53 abnormalities in 15 patients with LCC (5 classic LCC, 5 LCNEC, and 5 LCCNM) who had undergone resection with curative intent. Of these patients, 5/15 expressed p53 and none had mutant p53 sequences. There was a negative survival correlation with positive p53 immunostaining (P = 0.05). After adjustment for stage, age, gender, chemotherapy, radiotherapy, and histological subtypes by multivariate analysis, p53 expression had an independent impact on survival. The present study indicates that p53 assessment may provide an objective marker for the prognosis of LCC irrespective of morphological variants and suggests that p53 expression is important for outcome prediction in patients with the early stages of LCC. The results reported here should be considered to be initial results because tumors from only 15 patients were studied: 5 each from LCC, LCNEC and LCCNM. This was due to the rarity of these specific diseases.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Carcinoma, Large Cell/genetics , Carcinoma, Neuroendocrine/genetics , /genetics , Lung Neoplasms/genetics , Mutation/genetics , /metabolism , Carcinoma, Large Cell/metabolism , Carcinoma, Large Cell/mortality , Carcinoma, Large Cell/surgery , Carcinoma, Neuroendocrine/metabolism , Carcinoma, Neuroendocrine/mortality , Carcinoma, Neuroendocrine/surgery , DNA, Neoplasm/analysis , Exons , Immunohistochemistry , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Neoplasm Staging , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Prognosis , Survival Analysis , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism
13.
Genet. mol. res. (Online) ; 5(2): 315-322, 2006. tab
Article in English | LILACS | ID: lil-442567

ABSTRACT

The methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is associated with the expression of a thermolabile enzyme with decreased activity that influences the pool of methyl-donor molecules. Several studies have reported an association between C677T polymorphism and susceptibility to colorectal cancer (CRC). Considering that methylation abnormalities appear to be important for the pathogenesis of CRC, we examined the correlation between the genotype of the MTHFR C677T polymorphism, hypermethylation of the promoter region of five relevant genes (DAPK, MGMT, hMLH1, p16(INK4a), and p14(ARF)), and microsatellite instability, in 106 patients with primary CRCs in Brazil. We did not find significant differences in the genotypic frequencies of the MTHFR C677T polymorphism when one or more loci were hypermethylated. However, we did find a significant excess of 677TT individuals among patients with CRC who had microsatellite instability. This strong association was independent of the methylation status of hMLH1 and of the biogeographical genomic ancestry of the patients. Although the mechanism responsible for the link between the C677T polymorphism and microsatellite instability was not apparent, this finding may provide a clue towards a better understanding of the pathogenesis of microsatellite instability in human colorectal cancer.


Subject(s)
Humans , Male , Female , Biomarkers, Tumor/genetics , DNA Methylation , /genetics , Colorectal Neoplasms/genetics , Polymorphism, Genetic/genetics , Promoter Regions, Genetic , Case-Control Studies , Genotype , Genomic Instability/genetics , Colorectal Neoplasms/enzymology , Genetic Predisposition to Disease , Microsatellite Repeats/genetics
14.
Braz. j. med. biol. res ; 35(1): 91-97, Jan. 2002. ilus, tab
Article in English | LILACS | ID: lil-304188

ABSTRACT

Undernutrition of dams and pups disrupts the retrieval efficiency of mothers. However, if the mothers are assessed in their home cages, they spend more time with their litters. In the present study the effect of test conditions on pup retrieval behavior of mothers receiving a 25 percent (well-nourished group) and 8 percent casein diet (undernourished group) was examined. In agreement with previous studies, undernourished mothers spent more time with their litters than well-nourished dams as lactation proceeded. Pup retrieval behavior varied with test conditions. In the first experiment, the maternal behavior of dams was assessed by the standard procedure (pups were separated from their mother and scattered over the floor of the home cage). The mother was then returned and the number of retrieved pups was recorded. From day 3 to 8, the retrieval efficiency of undernourished dams decreased, while the retrieval efficiency of well-nourished mothers did not vary. In the second experiment, mothers were subjected to a single retrieval test (on day 9 of lactation) using the procedure described for experiment 1. No difference between well-nourished and undernourished mothers was observed. In the third experiment, seven-day-old pups were separated from the mothers and returned individually to a clean home cage. Dietary treatment did not affect the retrieval efficiency. However, undernourished dams reconstructed the nest more slowly than did well-nourished dams. Taken together, these results suggest that pup retrieval behavior of the undernourished mother is not impaired by dietary restriction when the maternal environment is disturbed minimally


Subject(s)
Animals , Female , Male , Rats , Behavior, Animal , Lactation/physiology , Maternal Behavior , Nutrition Disorders , Analysis of Variance , Animals, Suckling , Lactation/psychology , Maternal Behavior , Rats, Wistar
15.
Braz. j. med. biol. res ; 26(2): 191-201, Feb. 1993. ilus, tab
Article in English | LILACS | ID: lil-148685

ABSTRACT

1. Experimental models of carcinomatous lymphangitis have not been described. This is an important clinical entity which usually results in the patients' death, although its natural history is still controversial. This study was undertaken to investigate whether the pattern of lung involvement after Walker 256 tumor inoculation through the trachea is a good model of carcinomatous lymphangitis. 2. Fifty male Wistar rats were inoculated through the trachea with 2.5 x 10(6) Walker 256 tumor cells and killed in groups of 5 animals each at 6 h and on days 1, 3, 7, 14, 21, 28, 35, 45, and 60 of the experiment. The lungs and thoracic lymph nodes were examined by light microscopy. 3. There were no tumors in the 25 animals killed before the 21st day of the experiment. The remaining 25 rats were sacrificed after 3 weeks of the experiment; 52 per cent of them displayed thoracic lymph node metastases, and 40 per cent developed a mild carcinomatous lymphangitis. The lung involvement did not correlate with respiratory distress, tumor dissemination or additional histological abnormalities. 4. We conclude that invasion of the lung is possible after intratracheal tumor cell inoculation, and that spreading follows a lymphatic pattern. This finding establishes this approach as a viable experimental model of carcinomatous lymphangitis. New approaches to increase the intensity and frequency of lung involvement, as well as the development of respiratory distress should be pursued in order to improve the efficiency of this model


Subject(s)
Animals , Male , Rats , Carcinoma 256, Walker/pathology , Lung Neoplasms/secondary , Lymphangitis/etiology , Lymphatic Metastasis , Neoplasm Transplantation , Rats, Wistar , Time Factors
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