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1.
Chronic venous ulcer (CVU) is a major cause of chronic wounds of lower extremities and presents a significant financial and resource burden to health care systems worldwide. Defects in the vasculature, matrix deposition, and re-epithelialization are the main histopathological changes believed to impede healing. Supplementation of the amino acid arginine that plays a crucial role in the interactions that occur during inflammation and wound healing was proven clinically to improve acute wound healing probably through enhancing activity of inducible arginase (AI) locally in the wounds. However, the possible mechanism of arginine action and the potential beneficial effects of AI/arginine in human chronic wounds remain unclear. In the present study, using biopsies, taken under local anesthesia, from adult patients (n = 12, mean age 55 years old) with CVUs in lower extremities, we investigated the correlation between AI distribution in CVUs and the histopathological changes, mainly proliferative and vascular changes. Our results show a distinct spatial distribution of AI along the ulcer in the epidermis and in the dermis with the highest level of expression being at the ulcer edge and the least expression towards the ulcer base. The AI cellular immunoreactivity, enzymatic activity, and protein levels were significantly increased towards the ulcer edge. Interestingly, a similar pattern of expression was encountered in the proliferative and the vascular changes with strong correlations between AI and the proliferative activity and vascular changes. Furthermore, AI cellular distribution was associated with increased proliferative activity, inflammation, and vascular changes. Our findings of differential expression of AI along the CVU base, edge, and nearby surrounding skin and its associations with increased proliferative activity and vascular changes provide further support to the AI implication in CVU pathogenesis. The presence of high levels of AI in the epidermis of chronic wounds may serve as a molecular marker of impaired healing and may provide future targets for therapeutic intervention.  相似文献   
2.
Available data suggesting the occurrence of "bystander effects" (i.e. damage induction in cells not traversed by radiation) were collected and critically evaluated, in view of the development of low-dose risk models. Although the underlying mechanisms are largely unknown, cellular communication seems to play a key role. In this context, the main features of cellular communication were summarised and a few representative studies on bystander effects were reported and discussed. Three main approaches were identified: (1) conventional irradiation of cell cultures with very low doses of light ions; (2) irradiation of single cells with microbeam probes; (3) treatment with irradiated conditioned medium (ICM), i.e. feeding of unexposed cells with medium taken from irradiated cultures. Indication of different types of bystander damage (e.g. cell killing, gene mutations and modifications in gene expression) has been found in each of the three cases. The interpretations proposed by the investigators were discussed and possible biases introduced by specific experimental conditions were outlined. New arguments and experiments were suggested, with the main purpose of obtaining quantitative information to be included in models of low-dose radiation action. Implications in interpreting low-dose data and modelling low-dose effects at cellular and supra-cellular level, including cancer induction, were analysed. Possible synergism with other low-dose specific phenomena such as adaptive response (AR) (i.e. low-dose induced resistance to subsequent irradiation) was discussed.  相似文献   
3.
ABSTRACT: BACKGROUND: To study the diagnosis delay and its impact on stage of disease among women with breast cancer on Libya METHODS: 200 women, aged 22 to 75 years with breast cancer diagnosed during 2008--2009 were interviewed about the period from the first symptoms to the final histological diagnosis of breast cancer. This period (diagnosis time) was categorized into 3 periods: <3 months, 3--6 months, and >6 months. If diagnosis time was longer than 3 months, the diagnosis was considered delayed (diagnosis delay). Consultation time was the time taken to visit the general practitioner after the first symptoms. Retrospective preclinical and clinical data were collected on a form (questionnaire) during an interview with each patient and from medical records. RESULTS: The median of diagnosis time was 7.5 months. Only 30.0% of patients were diagnosed within 3 months after symptoms. 14% of patients were diagnosed within 3--6 months and 56% within a period longer than 6 months. A number of factors predicted diagnosis delay: Symptoms were not considered serious in 27% of patients. Alternative therapy (therapy not associated with cancer) was applied in 13.0% of the patients. Fear and shame prevented the visit to the doctor in 10% and 4.5% of patients, respectively. Inappropriate reassurance that the lump was benign was an important reason for prolongation of the diagnosis time. Diagnosis delay was associated with initial breast symptom(s) that did not include a lump (p < 0.0001), with women who did not report monthly self examination (p < 0.0001), with old age (p = 0.004), with illiteracy (p = 0.009), with history of benign fibrocystic disease (p = 0.029) and with women who had used oral contraceptive pills longer than 5 years (p = 0.043). At the time of diagnosis, the clinical stage distribution was as follows: 9.0% stage I, 25.5% stage II, 54.0% stage III and 11.5% stage IV.Diagnosis delay was associated with bigger tumour size (p <0.0001), with positive lymph nodes (N2, N3; p < 0.0001), with high incidence of late clinical stages (p < 0.0001), and with metastatic disease (p < 0.0001). CONCLUSIONS: Diagnosis delay is very serious problem in Libya. Diagnosis delay was associated with complex interactions between several factors and with advanced stages. There is a need for improving breast cancer awareness and training of general practitioners to reduce breast cancer mortality by promoting early detection. The treatment guidelines should pay more attention to the early phases of breast cancer. Especially, guidelines for good practices in managing detectable of tumors are necessary.  相似文献   
4.
PURPOSE: Performance of anatomical metrics of Response Evaluation Criteria in Solid Tumors (RECIST1.1) versus Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST1.0) for neoadjuvant chemoradiation (nCR) of pancreatic adenocarcinoma was evaluated based on the pathological treatment response (PTR) data. METHODS AND MATERIALS: The pre- and post-nCR CT and PET data for 14 patients with resectable or borderline resectable pancreatic head adenocarcinoma treated with nCR followed by surgery were retrospectively analyzed. These data were compared with the PTR which were graded according to tumor cell destruction (cellularity), with Grade 0, 1, 2 or 3 (G0, G1, G2 or G3) for complete, moderate, minimal and poor responses, respectively. Maximum standardized uptake value (SUVmax) was defined using body-weight (SUVbw). PERCIST1.0 was defined using lean-body mass normalized SUV (SUVlb or SUL). RECIST1.1 was defined by contouring the whole pancreas head on the CT image. Pre- and post-SUL-peak and SUVmax, RECIST1.1 and PETRECIST1.0 were correlated with PTR using Pearson’s correlation coefficient test. RESULTS: The average mean and SD in SUL-peak for all patients analyzed were lower in post-nCR (3.63±1.06) compared to those at pre-nCR (4.29±0.89). Using PERCIST1.0, 62% of patients showed stable metabolic disease (SMD), 23% partial metabolic response (PMR), and 15% progressive metabolic disease (PMD). Using RECIST1.1, 85% of patients showed stable disease (SD), 8% partial response (PR), and 7% progressive diseases (PD). A poor insignificant correlation was established between PRT and PERECIST1.0 (r=0.121), whereas no correlation was seen with RECIST1.1. CONCLUSIONS: PERCIST1.0 appears to increase the chance of detecting patients with progressive disease compared to the conventional anatomical-based assessment of RECIST1.1. The integration of these additional radiographic metrics in assessing treatment response to nCR for pancreatic adenocarcinoma may provide a promising strategy to better select patients that are most suitable for therapeutic intensification.  相似文献   
5.
Molecular Biology Reports - Carmustine (Cr) is an important chemotherapeutic drug, widely used in the treatment of brain tumors. Herein, the protective role of Codiaeum variegatum leaves ethyl...  相似文献   
6.
The genotoxic potential of beryllium chloride (BeCl2) was evaluated in vivo in mice using different endpoints. Chromosomal aberrations in bone marrow cells and in spermatocytes as well as sperm abnormalities were determined in the tested mice. The protective role of an orally administered drug consisting of selenium and vitamins A, C and E (selenium–ACE) was also studied.For analysis of chromosomal aberrations, both single and repeated oral treatments for a period of 3 weeks were performed. The doses used were 93.75, 187.50, 375, and 750 mg BeCl2/kg bw, which corresponds to 1/16, 1/8, 1/4, and 1/2 of the experimental LD50.BeCl2 induced a statistically significant increase in the percentage of chromosomal aberrations in both somatic and germ cells, with a dose– and time–response. The percentage of induced chromosomal aberrations was significantly reduced in all BeCl2-treated groups after oral administration of selenium–ACE.Beryllium chloride also induced a significant increase in the percentage of abnormal sperm. This percentage reached values of 9.62 ± 0.32 and 5.56 ± 0.31 in mice treated with the highest test dose of BeCl2 and with BeCl2 + selenium–ACE, respectively, compared with 1.96 ± 0.14 for the control.In conclusion, the results demonstrate the genotoxic effect of beryllium chloride and confirm the protective role of selenium–ACE against the genotoxicity of beryllium chloride.  相似文献   
7.
In case of a life-threatening, stressful event, the body prepares for an emergency. Indeed, the lung is unique in which alveolar cells are constantly exposed to physical and chemical stresses. This study aimed to study the impact of immobilization stress on the blood–air barrier and how it initiate and maintain an inflammatory response, plus determining the resolution of lung inflammation and repair. There was a significant increase in the plasma levels of stress markers “corticosterone and catecholamines” with a decrease in surfactant protein A (a lung-injury marker). Chronic stress produced a significant increase in the pulmonary oxidative and inflammatory markers malondialdehyde, tumor necrosis factor α, and induced nitric oxide synthase when compared with that of acute stress. Both stresses provoked marked pulmonary morphological and ultrastructural changes with a significant increase in caspase-3 immunoexpression. There was increasing evidence of lung’s capacity for repair. This process involved edema resolution, cell proliferation, and tissue remodeling in improving the lung-injury, oxidative, and inflammatory markers.  相似文献   
8.
The genotoxic potential of beryllium chloride (BeCl2) was evaluated in vivo in mice using different endpoints. Chromosomal aberrations in bone marrow cells and in spermatocytes as well as sperm abnormalities were determined in the tested mice. The protective role of an orally administered drug consisting of selenium and vitamins A, C and E (selenium-ACE) was also studied. For analysis of chromosomal aberrations, both single and repeated oral treatments for a period of 3 weeks were performed. The doses used were 93.75, 187.50, 375, and 750 mg BeCl2/kg bw, which corresponds to 1/16, 1/8, 1/4, and 1/2 of the experimental LD50. BeCl2 induced a statistically significant increase in the percentage of chromosomal aberrations in both somatic and germ cells, with a dose- and time-response. The percentage of induced chromosomal aberrations was significantly reduced in all BeCl2-treated groups after oral administration of selenium-ACE. Beryllium chloride also induced a significant increase in the percentage of abnormal sperm. This percentage reached values of 9.62 +/- 0.32 and 5.56 +/- 0.31 in mice treated with the highest test dose of BeCl2 and with BeCl2+selenium-ACE, respectively, compared with 1.96 +/- 0.14 for the control. In conclusion, the results demonstrate the genotoxic effect of beryllium chloride and confirm the protective role of selenium-ACE against the genotoxicity of beryllium chloride.  相似文献   
9.
Raman spectroscopy was employed as a nondestructive technique for the analysis of dry traces of oral fluid to differentiate between smoker and nonsmoker donors with the aid of advanced statistical tools. A genetic algorithm (GA) was used to determine eight spectral regions that contribute the most to the differentiation of smokers and nonsmokers. Thereafter, a classification model was developed based on the artificial neural network (ANN) that showed 100% accuracy after external validation. (Image ©: Dr. Aliaksandra Sikirzhytskaya). Further details can be found in the article by Entesar Al‐Hetlani, Lenka Halamkova, Mohamed O. Amin, and Igor K. Lednev ( e201960123 ).

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10.
PURPOSE: To investigate the feasibility of using apparent diffusion coefficient (ADC) to assesspathological treatment response in pancreatic ductal adenocarcinoma (PDAC) following neoadjuvant chemoradiation (nCR). MATERIALS/METHODS: MRI and pathological data collected for 25patients with resectable and borderline resectable PDAC following nCR were retrospectively analyzed. Pre- and post-nCR mean ADC values in the tumors were compared using Wilcoxon matched pairs test. Correlation of pathological treatment response and ADC values was assessed using Pearson’s correlation coefficient test and receiver-operating-curve (ROC) analysis. RESULTS: The average mean and standard deviation (SD) of the ADC values for all the patients analyzed were significantly higher in post-nCR (1.667±0.161×10-3) compared with those prior to nCR (1.395±0.136×10-3 mm2/sec), (P<0.05). The mean ADC values after nCR were significantly correlated with the pathological responses (r=-0.5172); P=0.02. The area under the curve (AUC) of the ADC values for differentiating G1, G2 and G3 pathological responses, using ROC analysis, was found to be 0.6310 and P=0.03. CONCLUSION: Changes of pre- and post-treatment ADC values significantly correlated with pathological treatment response for PDAC patients treated with chemoradiation therapy, indicating that the ADC could be used to assesstreatment response for PDAC.  相似文献   
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