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101.
Transport of molecules across tumor vasculature 总被引:16,自引:0,他引:16
Rakesh K. Jain 《Cancer metastasis reviews》1987,6(4):559-593
The vascular-extravascular exchange of fluid and solute molecules in a tissue is determined by three transport parameters (vascular permeability, P, hydraulic conductivity, Lp, and reflection coefficient, ); the surface area for exchange, A; and the transluminal concentration and pressure gradients. The transport parameters and the exchange area for a given molecule are governed by the structure of the vessel wall. In general, tumor vessels have wide interendothelial junctions; large number of fenestrae and transendothelial channels formed by vesicles; and discontinuous or absent basement membrane. While these factors favor movement of molecules across tumor vessels, high interstitial pressure and low microvascular pressure may retard extravasation of molecules and cells, especially in large tumors. These characteristics of the transvascular transport have significant implications in tumor growth, metastasis, detection and treatment. 相似文献
102.
Macrocarposide, a new isoflavanone c-glucoside from Pterocarpus macrocarpus heart wood 总被引:1,自引:0,他引:1
Macrocarposide has been isolated for the first time as a natural product from the heartwood of PTEROCARPUS MACROCARPUS along with some known compounds. Based on its spectral and chemical evidence, it has been assigned the structure dalbergioidin-6- C-glucoside ( 1). 相似文献
103.
Journal of Public Health - The COVID-19 pandemic presents serious threats to global public health and the world economy. Therefore, the rapid escalation of the number of cases has led to national... 相似文献
104.
Maria De Angelis Sonya Siragusa Mirco Vacca Raffaella Di Cagno Fernanda Cristofori Michael Schwarm Stefan Pelzer Monika Flügel Bodo Speckmann Ruggiero Francavilla Marco Gobbetti 《Nutrients》2021,13(3)
This work aimed to define the microbial consortia that are able to digest gluten into non-toxic and non-immunogenic peptides in the human gastrointestinal tract. Methods: 131 out of 504 tested Bacillus and lactic acid bacteria, specifically Bacillus (64), lactobacilli (63), Pediococcus (1), and Weissella (3), showed strong gastrointestinal resistance and were selected for their PepN, PepI, PepX, PepO, and PepP activities toward synthetic substrates. Based on multivariate analysis, 24 strains were clearly distinct from the other tested strains based on having the highest enzymatic activities. As estimated by RP-HPLC and nano-ESI–MS/MS, 6 cytoplasmic extracts out of 24 selected strains showed the ability to hydrolyze immunogenic epitopes, specifically 57–68 of α9-gliadin, 62–75 of A-gliadin, 134–153 of γ-gliadin, and 57–89 (33-mer) of α2-gliadin. Live and lysed cells of selected strains were combined into different microbial consortia for hydrolyzing gluten under gastrointestinal conditions. Commercial proteolytic enzymes (Aspergillus oryzae E1, Aspergillus niger E2, Bacillus subtilis Veron HPP, and Veron PS proteases) were also added to each microbial consortium. Consortium activity was evaluated by ELISA tests, RP-HPLC-nano-ESI–MS/MS, and duodenal explants from celiac disease patients. Results: two microbial consortia (Consortium 4: Lactiplantibacillus (Lp.) plantarum DSM33363 and DSM33364, Lacticaseibacillus (Lc.) paracasei DSM33373, Bacillus subtilis DSM33298, and Bacillus pumilus DSM33301; and Consortium 16: Lp. plantarum DSM33363 and DSM33364, Lc. paracasei DSM33373, Limosilactobacillus reuteri DSM33374, Bacillus megaterium DSM33300, B. pumilus DSM33297 and DSM33355), containing commercial enzymes, were able to hydrolyze gluten to non-toxic and non-immunogenic peptides under gastrointestinal conditions. Conclusions: the results of this study provide evidence that selected microbial consortia could potentially improve the digestion of gluten in gluten-sensitive patients by hydrolyzing the immunogenic peptides during gastrointestinal digestion. 相似文献
105.
Monika Grabia Anna Pucion-Jakubik Renata Markiewicz-ukowska Joanna Bielecka Anita Mielech Patryk Nowakowski Katarzyna Socha 《Nutrients》2021,13(4)
An appropriate balanced diet and dietary patterns are important at every stage of life, but in the case of young patients with type 1 diabetes mellitus (T1DM), it is especially crucial during the COVID-19 pandemic. The aim of the study was to assess health and nutritional behaviors, mainly adherence to the Mediterranean diet (MD), during the second wave of the COVID-19 pandemic in Poland among women with T1DM, and to compare them with a healthy population. This survey (based on a questionnaire) was conducted in December 2020 and included 219 young women, healthy (n = 106) and with T1DM (n = 113), from northeast Poland. Over 30% of the study group admitted that they did not engage in any physical activity. A large proportion declared that their screen time was 5–7 h a day (48% in control and 40% in T1DM group). High intakes of sweet-beverages, sweets and red meat, but also low intakes of olive oil, fish and nuts were observed. The vast majority of participants (60% vs. 71%) were moderately adherent to the Mediterranean Diet Adherence Screener (MEDAS). The study demonstrated that despite the similarity between the behaviors of healthy people and those with T1DM, negative health and nutritional practices, such as low physical activity, long screen time, medium and high levels of stress and inappropriate eating habits were observed. 相似文献
106.
Monika M. Stojek Justyna Lipka Jessica M. Maples-Keller Sheila A. M. Rauch Kathryn Black Vasiliki Michopoulos Barbara O. Rothbaum 《Nutrients》2021,13(6)
Background: Food addiction (FA) is a dysregulated eating pattern characterized by difficulties in controlling the intake of certain foods. There is an overlap in physical and mental health correlates of FA and post-traumatic stress disorder (PTSD). The purpose of this study was to examine sex differences in the rates of positive FA status in individuals with threshold/subthreshold PTSD, and to examine sex differences in the physical and mental health correlates of FA. Methods: Post-9/11 veterans/service members seeking PTSD treatment were recruited. Participants were diagnosed with PTSD via the administration of a clinical interview. FA status was determined using Modified Yale Food Addiction Scale-2, binary sex and body mass index were assessed with demographics questions. Results: Nearly half (43%) of the sample were women. There were no sex differences in the rates of FA, with an overall FA prevalence of 18%. There were no sex differences in FA symptom count in the whole sample (M = 1.63) or those with FA status (M = 6.21). Individuals with FA reported higher frequency of disordered eating, higher severity of PTSD, and depression symptoms. Conclusions: FA should be assessed in tandem with PTSD symptoms, as its prevalence in that sample is higher than in the general population, and it appears to affect both sexes at similar rates. 相似文献
107.
Sina Schwarzkopf Adalbert Krawczyk Dietmar Knop Hannes Klump Andreas Heinold Falko M. Heinemann Laura Thümmler Christian Temme Marianne Breyer Oliver Witzke Ulf Dittmer Veronika Lenz Peter A. Horn Monika Lindemann 《Emerging infectious diseases》2021,27(1):122
We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells. 相似文献
108.
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110.
Satinder Kumar Jain Virwar Kumar Jha Ganesh Kumar Mani 《Indian Journal of Thoracic and Cardiovascular Surgery》2021,37(4):438
A 46-year-old male presented with breathlessness for a few months. He had been operated twice for liver hydatid cysts and once for right pulmonary hydatid cysts at other hospitals. Now he was found to have one hydatid cyst in the upper lobe of the left lung and multiple hydatid cysts adjoining left heart border. On computed tomography (CT) scan chest and echocardiography, it was difficult to ascertain whether these cysts were pulmonary or intrapericardial. Left ventricular ejection fraction (LVEF) was 25%. Enzyme-linked immunosorbent assay (ELISA) was positive for hydatid. Left posterolateral thoracotomy revealed dead hydatid cyst in upper lobe of the lung that was removed. Infected mother hydatid cyst was encountered inside pericardial sac. Scores of daughter hydatid cysts, varying in size from 1 to 30 mm, were scooped out intact from the pericardial cavity. There was significant improvement in cardiac activity, once the tamponade effect of hydatid cyst was removed. Pericardium was about 1 cm thick with lot of purulent and necrotic slough. To prevent future constrictive pericarditis, subtotal pericardiectomy was done. Intrapericardial hydatid cyst should be kept in mind whenever it obscures the heart border and patient has features of cardiac tamponade. Early surgical intervention may be required in these cases. 相似文献