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1.
Brain ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808482

RESUMO

Comprehensive understanding of the neural circuits involving the ventral tegmental area is essential for elucidating the anatomo-functional mechanisms governing human behaviour as well as the therapeutic and adverse effects of deep brain stimulation for neuropsychiatric diseases. While the ventral tegmental area has been successfully targeted with deep brain stimulation for different neuropsychiatric diseases, the axonal connectivity of the region has not been fully understood. Here using fiber micro-dissections in human cadaveric hemispheres, population-based high-definition fiber tractography, and previously reported deep brain stimulation hotspots, we find that the ventral tegmental area participates in an intricate network involving the serotonergic pontine nuclei, basal ganglia, limbic system, basal forebrain, and prefrontal cortex, which is implicated in the treatment of obsessive-compulsive disorder, major depressive disorder, Alzheimer's disease, cluster headaches, and aggressive behaviors.

2.
Adv Radiat Oncol ; 9(6): 101492, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38711960

RESUMO

Purpose: Ultra High Dose-Rate (UHDR) radiation has been reported to spare normal tissue, compared with Conventional Dose-Rate (CDR) radiation. However, important work remains to be done to improve the reproducibility of the FLASH effect. A better understanding of the biologic factors that modulate the FLASH effect may shed light on the mechanism of FLASH sparing. Here, we evaluated whether sex and/or the use of 100% oxygen as a carrier gas during irradiation contribute to the variability of the FLASH effect. Methods and Materials: C57BL/6 mice (24 male, 24 female) were anesthetized using isoflurane mixed with either room air or 100% oxygen. Subsequently, the mice received 27 Gy of either 9 MeV electron UHDR or CDR to a 1.6 cm2 diameter area of the right leg skin using the Mobetron linear accelerator. The primary postradiation endpoint was time to full thickness skin ulceration. In a separate cohort of mice (4 male, 4 female), skin oxygenation was measured using PdG4 Oxyphor under identical anesthesia conditions. Results: Neither supplemental oxygen nor sex affected time to ulceration in CDR irradiated mice. In the UHDR group, skin damage occured earlier in male and female mice that received 100% oxygen compared room air and female mice ulcerated sooner than male mice. However, there was no significant difference in time to ulceration between male and female UHDR mice that received room air. Oxygen measurements showed that tissue oxygenation was significantly higher when using 100% oxygen as the anesthesia carrier gas than when using room air, and female mice showed higher levels of tissue oxygenation than male mice under 100% oxygen. Conclusions: The skin FLASH sparing effect is significantly reduced when using oxygen during anesthesia rather than room air. FLASH sparing was also reduced in female mice compared to male mice. Both tissue oxygenation and sex are likely sources of variability in UHDR studies. These results suggest an oxygen-based mechanism for FLASH, as well as a key role for sex in the FLASH skin sparing effect.

3.
Cancer Treat Res Commun ; 38: 100789, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38262125

RESUMO

BACKGROUND: Glioblastoma is the most common primary malignant and treatment-resistant human brain tumor. Rodent models have played an important role in understanding brain cancer biology and treatment. However, due to their small cranium and tumor volume mismatch, relative to human disease, they have been less useful for translational studies. Therefore, development of a consistent and simple large animal glioma xenograft model would have significant translational benefits. METHODS: Immunosuppression was induced in twelve standard Yucatan minipigs. 3 pigs received cyclosporine only, while 9 pigs received a combined regimen including cyclosporine (55 mg/kg q12 h), prednisone (25 mg, q24 h) and mycophenolate (500 mg q24 h). U87 cells (2 × 106) were stereotactically implanted into the left frontal cortex. The implanted brains were imaged by MRI for monitoring. In a separate study, tumors were grown in 5 additional pigs using the combined regimen, and pigs underwent tumor resection with intra-operative image updating to determine if the xenograft model could accurately capture the spatial tumor resection challenges seen in humans. RESULTS: Tumors were successfully implanted and grown in 11 pigs. One animal in cyclosporine only group failed to show clinical tumor growth. Clinical tumor growth, assessed by MRI, progressed slowly over the first 10 days, then rapidly over the next 10 days. The average tumor growth latency period was 20 days. Animals were monitored twice daily and detailed records were kept throughout the experimental period. Pigs were sacrificed humanely when the tumor reached 1 - 2 cm. Some pigs experienced decreased appetite and activity, however none required premature euthanasia. In the image updating study, all five pigs demonstrated brain shift after craniotomy, consistent with what is observed in humans. Intraoperative image updating was able to accurately capture and correct for this shift in all five pigs. CONCLUSION: This report demonstrates the development and use of a human intracranial glioma model in an immunosuppressed, but nongenetically modified pig. While the immunosuppression of the model may limit its utility in certain studies, the model does overcome several limitations of small animal or genetically modified models. For instance, we demonstrate use of this model for guiding surgical resection with intraoperative image-updating technologies. We further report use of a surrogate extracranial tumor that indicates growth of the intracranial tumor, allowing for relative growth assessment without radiological imaging.


Assuntos
Neoplasias Encefálicas , Ciclosporinas , Glioma , Humanos , Suínos , Animais , Xenoenxertos , Reprodutibilidade dos Testes , Porco Miniatura , Glioma/tratamento farmacológico , Glioma/cirurgia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Terapia de Imunossupressão , Modelos Animais de Doenças
4.
bioRxiv ; 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37961549

RESUMO

Introduction: Ultra-high dose-rate (UHDR) radiation has been reported to spare normal tissue compared to conventional dose-rate (CDR) radiation. However, reproducibility of the FLASH effect remains challenging due to varying dose ranges, radiation beam structure, and in-vivo endpoints. A better understanding of these inconsistencies may shed light on the mechanism of FLASH sparing. Here, we evaluate whether sex and/or use of 100% oxygen as carrier gas during irradiation contribute to the variability of the FLASH effect. Methods: C57BL/6 mice (24 male, 24 female) were anesthetized using isoflurane mixed with either room air or 100% oxygen. Subsequently, the mice received 27 Gy of either 9 MeV electron UHDR or CDR to a 1.6 cm2 diameter area of the right leg skin using the Mobetron linear accelerator. The primary post-radiation endpoint was time to full thickness skin ulceration. In a separate cohort of mice (4 male, 4 female) skin oxygenation was measured using PdG4 Oxyphor under identical anesthesia conditions. Results: In the UHDR group, time to ulceration was significantly shorter in mice that received 100% oxygen compared to room air, and amongst them female mice ulcerated sooner compared to males. However, no significant difference was observed between male and female UHDR mice that received room air. Oxygen measurements showed significantly higher tissue oxygenation using 100% oxygen as the anesthesia carrier gas compared to room air, and female mice showed higher levels of tissue oxygenation compared to males under 100% oxygen. Conclusion: The FLASH sparing effect is significantly reduced using oxygen during anesthesia compared to room air. The FLASH sparing was significantly lower in female mice compared to males. Both tissue oxygenation and sex are likely sources of variability in UHDR studies. These results suggest an oxygen-based mechanism for FLASH, as well as a key role for sex in the FLASH skin sparing effect.

5.
Int J Mol Sci ; 24(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37762046

RESUMO

Radiation therapy (RT) has recently demonstrated promise at stimulating an enhanced immune response. The recent success of immunotherapies, such as checkpoint inhibitors, CART cells, and other immune modulators, affords new opportunities for combination with radiation. The aim of this study is to evaluate whether and to what extent blockade of VISTA, an immune checkpoint, can potentiate the tumor control ability of radiation therapy. Our study is novel in that it is the first comparison of two VISTA-blocking methods (antibody inhibition and genetic knockout) in combination with RT. VISTA was blocked either through genetic knockout (KO) or an inhibitory antibody and combined with RT in two syngeneic murine flank tumor models (B16 and MC38). Selected mRNA, immune cell infiltration, and tumor growth delay were used to assess the biological effects. When combined with a single 15Gy radiation dose, VISTA blockade via genetic knockout in the B16 model and via anti-VISTA antibodies in the MC38 model significantly improved survival compared to RT alone by an average of 5.5 days and 6.3 days, respectively (p < 0.05). The gene expression data suggest that the mechanism behind the enhanced tumor control is primarily a result of increased apoptosis and immune-mediated cytotoxicity. VISTA blockade significantly enhances the anti-tumor effect of a single dose of 15Gy radiation through increased expression and stimulation of cell-mediated apoptosis pathways. These results suggest that VISTA is a biologically relevant immune promoter that has the potential to enhance the efficacy of a large single radiation dose in a synergic manner.


Assuntos
Adenocarcinoma , Melanoma , Animais , Camundongos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Anticorpos , Modelos Animais de Doenças , Melanoma/tratamento farmacológico , Melanoma/radioterapia , Linfócitos T , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico
6.
ACS Omega ; 7(47): 43242-43253, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36467941

RESUMO

This work confirmed theoretically whether adsorption azeotropes can form in a binary gas mixture at a pressure P below the intersection pressure of the corresponding single-gas isotherms. The thermodynamically consistent dual-process Langmuir (DPL) model with equal component i saturation capacities q i, j s on site j and the general DPL model with nonequal q i, j s on site j were used for this purpose. Relationships derived from both DPL models, in terms of the single-gas isotherm DPL model parameters, were used to answer this question. When the P range where adsorption azeotropes always exist is infinite beyond the onset P of adsorption azeotropic formation, both DPL models and experimental data showed that it is possible to form adsorption azeotropes in the corresponding binary gas mixture at pressures not only above but even below the single-gas isotherm intersection P. When the P range where adsorption azeotropes always exist is finite beyond the onset P of adsorption azeotropic formation, only the general DPL model predicts the onset P of this finite P range can be below the intersection P of the corresponding single-gas isotherms. Without theoretical proof, the thermodynamically consistent DPL model seemingly restricts this P range to be equal to or greater than the intersection P of the corresponding single-gas isotherms. For a finite P region where adsorption azeotropes always exist in a binary gas mixture, the binary selectivity inverts when traversing from below the lower onset P to the higher cessation P. Both models also showed, counterintuitively, that perfect positive energetic site matching can result in the formation of adsorption azeotropes in binary gas mixtures, not just perfect negative energetic site matching. Overall, this work provides some confirmation that it is indeed possible to form adsorption azeotropes in a binary gas mixture at pressures below the intersection P of the corresponding single-gas isotherms based on two physically sound formulations of the DPL model.

7.
Proc Natl Acad Sci U S A ; 119(30): e2114100119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858401

RESUMO

Salamanders are an important group of living amphibians and model organisms for understanding locomotion, development, regeneration, feeding, and toxicity in tetrapods. However, their origin and early radiation remain poorly understood, with early fossil stem-salamanders so far represented by larval or incompletely known taxa. This poor record also limits understanding of the origin of Lissamphibia (i.e., frogs, salamanders, and caecilians). We report fossils from the Middle Jurassic of Scotland representing almost the entire skeleton of the enigmatic stem-salamander Marmorerpeton. We use computed tomography to visualize high-resolution three-dimensional anatomy, describing morphologies that were poorly characterized in early salamanders, including the braincase, scapulocoracoid, and lower jaw. We use these data in the context of a phylogenetic analysis intended to resolve the relationships of early and stem-salamanders, including representation of important outgroups alongside data from high-resolution imaging of extant species. Marmorerpeton is united with Karaurus, Kokartus, and others from the Middle Jurassic-Lower Cretaceous of Asia, providing evidence for an early radiation of robustly built neotenous stem-salamanders. These taxa display morphological specializations similar to the extant cryptobranchid "giant" salamanders. Our analysis also demonstrates stem-group affinities for a larger sample of Jurassic species than previously recognized, highlighting an unappreciated diversity of stem-salamanders and cautioning against the use of single species (e.g., Karaurus) as exemplars for stem-salamander anatomy. These phylogenetic findings, combined with knowledge of the near-complete skeletal anatomy of Mamorerpeton, advance our understanding of evolutionary changes on the salamander stem-lineage and provide important data on early salamanders and the origins of Batrachia and Lissamphibia.


Assuntos
Evolução Biológica , Fósseis , Urodelos , Animais , Filogenia , Crânio/anatomia & histologia , Urodelos/anatomia & histologia , Urodelos/classificação
8.
Cell Commun Signal ; 20(1): 44, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35392976

RESUMO

The main breakthrough in tumor immunotherapy was the discovery of immune checkpoint (IC) proteins, which act as a potent suppressor of the immune system by a myriad of mechanisms. After that, scientists focused on the immune checkpoint molecules mainly. Thereby, much effort was spent to progress novel strategies for suppressing these inhibitory axes, resulting in the evolution of immune checkpoint inhibitors (ICIs). Then, ICIs have become a promising approach and shaped a paradigm shift in tumor immunotherapies. CTLA-4 plays an influential role in attenuation of the induction of naïve and memory T cells by engagement with its responding ligands like B7-1 (CD80) and B7-2 (CD86). Besides, PD-1 is predominantly implicated in adjusting T cell function in peripheral tissues through its interaction with programmed death-ligand 1 (PD-L1) and PD-L2. Given their suppressive effects on anti-tumor immunity, it has firmly been documented that ICIs based therapies can be practical and rational therapeutic approaches to treat cancer patients. Nonetheless, tumor inherent or acquired resistance to ICI and some treatment-related toxicities restrict their application in the clinic. The current review will deliver a comprehensive overview of the ICI application to treat human tumors alone or in combination with other modalities to support more desired outcomes and lower toxicities in cancer patients. Video Abstract.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias , Antígeno B7-H1 , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Neoplasias/tratamento farmacológico
9.
Langmuir ; 37(46): 13584-13594, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34748703

RESUMO

This work theoretically assessed the necessary and sufficient conditions for the formation of an adsorption azeotrope in a binary gas mixture when this mixture exhibits either intersecting or nonintersecting single gas isotherms. The thermodynamically consistent dual process Langmuir (DPL) model with equal component i saturation capacities qi,js on site j and the general DPL model with nonequal qi,js on site j were used for this purpose. Analytical expressions derived for both DPL models, in terms of the single gas isotherm DPL model parameters, were used to find examples or to determine theoretically when an adsorption azeotrope forms in a binary gas mixture for both intersecting and nonintersecting single gas isotherms. For the general DPL model, it was determined that neither necessary nor sufficient conditions exist for the formation of an adsorption azeotrope in a binary gas mixture. This means that an adsorption azeotrope can form irrespective of whether the corresponding single gas isotherms intersect or not. For the thermodynamically consistent DPL model, it was determined that the intersection of the single gas isotherms is a sufficient condition for the formation of an adsorption azeotrope in a binary gas mixture, but it is not a necessary condition. This means that intersecting single gas isotherms guarantee the formation of an adsorption azeotrope in the corresponding binary gas mixture, while nonintersecting single gas isotherms can also result in the formation of an adsorption azeotrope in the corresponding binary gas mixture. Overall, this analysis provides a well-posed resolution to the question of necessity and sufficiency for the formation of adsorption azeotropes in binary gas mixtures and the intersection of their corresponding single gas isotherms based on two physically sound formulations of the very popular DPL model.

10.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34301898

RESUMO

Teleost fishes comprise one-half of all vertebrate species and possess a duplicated genome. This whole-genome duplication (WGD) occurred on the teleost stem lineage in an ancient common ancestor of all living teleosts and is hypothesized as a trigger of their exceptional evolutionary radiation. Genomic and phylogenetic data indicate that WGD occurred in the Mesozoic after the divergence of teleosts from their closest living relatives but before the origin of the extant teleost groups. However, these approaches cannot pinpoint WGD among the many extinct groups that populate this 50- to 100-million-y lineage, preventing tests of the evolutionary effects of WGD. We infer patterns of genome size evolution in fossil stem-group teleosts using high-resolution synchrotron X-ray tomography to measure the bone cell volumes, which correlate with genome size in living species. Our findings indicate that WGD occurred very early on the teleost stem lineage and that all extinct stem-group teleosts known so far possessed duplicated genomes. WGD therefore predates both the origin of proposed key innovations of the teleost skeleton and the onset of substantial morphological diversification in the clade. Moreover, the early occurrence of WGD allowed considerable time for postduplication reorganization prior to the origin of the teleost crown group. This suggests at most an indirect link between WGD and evolutionary success, with broad implications for the relationship between genomic architecture and large-scale evolutionary patterns in the vertebrate Tree of Life.


Assuntos
Evolução Molecular , Peixes/genética , Fósseis , Duplicação Gênica , Genoma , Genômica/métodos , Animais , Filogenia
12.
J Evol Biol ; 33(6): 808-830, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144878

RESUMO

Osteocytes, cells embedded within the bone mineral matrix, inform on key aspects of vertebrate biology. In particular, a relationship between volumes of the osteocytes and bone growth and/or genome size has been proposed for several tetrapod lineages. However, the variation in osteocyte volume across different scales is poorly characterized and mostly relies on incomplete, two-dimensional information. In this study, we characterize the variation of osteocyte volumes in ray-finned fishes (Actinopterygii), a clade including more than half of modern vertebrate species in which osteocyte biology is poorly known. We use X-ray synchrotron micro-computed tomography (SRµCT) to achieve a three-dimensional visualization of osteocyte lacunae and direct measurement of their size (volumes). Our specimen sample is designed to characterize variation in osteocyte lacuna morphology at three scales: within a bone, among the bones of one individual and among species. At the intra-bone scale, we find that osteocyte lacunae vary noticeably in size between zones of organized and woven bone (being up to six times larger in woven bone), and across cyclical bone deposition. This is probably explained by differences in bone deposition rate, with larger osteocyte lacunae contained in bone that deposits faster. Osteocyte lacuna volumes vary 3.5-fold among the bones of an individual, and this cannot readily be explained by variation in bone growth rate or other currently observable factors. Finally, we find that genome size provides the best explanation of variation in osteocyte lacuna volume among species: actinopterygian taxa with larger genomes (polyploid taxa in particular) have larger osteocyte lacunae (with a ninefold variation in median osteocyte volume being measured). Our findings corroborate previous two-dimensional studies in tetrapods that also observed similar patterns of intra-individual variation and found a correlation with genome size. This opens new perspectives for further studies on bone evolution, physiology and palaeogenomics in actinopterygians, and vertebrates as a whole.


Assuntos
Evolução Biológica , Osso e Ossos/citologia , Carpas/anatomia & histologia , Tamanho do Genoma , Osteócitos/citologia , Animais , Osso e Ossos/diagnóstico por imagem , Carpas/genética , Microtomografia por Raio-X
13.
Ann Surg Oncol ; 26(13): 4213-4221, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605327

RESUMO

BACKGROUND: The risk of surgery, particularly for older cancer patients with serious, extensive comorbidities, can make this otherwise curative modality precarious. Leveraging data from the American College of Surgeons Oncology Group, this study sought to characterize age-based comparative demographics, adverse event rates, and study completion rates to define how best to conduct research in older cancer patients. METHODS: This study relied on clinical data from 21 completed studies to assess whether older patients experienced more grade 3 or worse adverse events and were more likely to discontinue study participation prematurely than their younger counterparts. RESULTS: The study enrolled 12,367 patients. The median age was 60 years, and 36% of the patients were 65 years of age or older. Among 4008 patients with adverse event data, 1067 (27%) had experienced a grade 3 or worse event. The patients 65 years or older had higher rates of grade 3 or worse adverse events compared to younger patients [32% vs. 24%; odds ratio (OR), 1.5; 95% confidence interval (CI), 1.3-1.7; p < 0.0001]. This association was not observed in multivariate analyses. The study protocol was completed by 97% of the patients. No association was observed between age and trial completion (OR 0.8; 95% CI 0.7-1.1; p = 0.14). Only the older gastrointestinal cancer trial patients were less likely to complete their studies compared to younger patients (OR 0.50; 95% CI 0.30-0.70; p < 0.0001). CONCLUSION: Despite higher rates of adverse events, the older patients typically completed the study protocol, thereby contributing relevant data on how best to render care to older cancer patients and affirming the important role of enrolling these patients to surgical trials.


Assuntos
Ensaios Clínicos como Assunto , Neoplasias/cirurgia , Cirurgiões/estatística & dados numéricos , Procedimentos Cirúrgicos Operatórios/mortalidade , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Prognóstico , Estudos Prospectivos , Sociedades Médicas , Taxa de Sobrevida
14.
Biol Rev Camb Philos Soc ; 94(4): 1338-1363, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30924235

RESUMO

Vertebrate bone is composed of three main cell types: osteoblasts, osteoclasts and osteocytes, the latter being by far the most numerous. Osteocytes are thought to play a fundamental role in bone physiology and homeostasis, however they are entirely absent in most extant species of teleosts, a group that comprises the vast majority of bony 'fishes', and approximately half of vertebrates. Understanding how this acellular (anosteocytic) bone appeared and was maintained in such an important vertebrate group has important implications for our understanding of the function and evolution of osteocytes. Nevertheless, although it is clear that cellular bone is ancestral for teleosts, it has not been clear in which specific subgroup the osteocytes were lost. This review aims to clarify the phylogenetic distribution of cellular and acellular bone in teleosts, to identify its precise origin, reversals to cellularity, and their implications. We surveyed the bone type for more than 600 fossil and extant ray-finned fish species and optimised the results on recent large-scale molecular phylogenetic trees, estimating ancestral states. We find that acellular bone is a probable synapomorphy of Euteleostei, a group uniting approximately two-thirds of teleost species. We also confirm homoplasy in these traits: acellular bone occurs in some non-euteleosts (although rarely), and cellular bone was reacquired several times independently within euteleosts, in salmons and relatives, tunas and the opah (Lampris sp.). The occurrence of peculiar ecological (e.g. anadromous migration) and physiological (e.g. red-muscle endothermy) strategies in these lineages might explain the reacquisition of osteocytes. Our review supports that the main contribution of osteocytes in teleost bone is to mineral homeostasis (via osteocytic osteolysis) and not to strain detection or bone remodelling, helping to clarify their role in bone physiology.


Assuntos
Evolução Biológica , Remodelação Óssea/fisiologia , Osso e Ossos/metabolismo , Peixes/genética , Peixes/fisiologia , Osteócitos/fisiologia , Animais , Filogenia
15.
Ind Eng Chem Res ; 55(16): 4734-4748, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31359909

RESUMO

This work examined in detail the a priori prediction of the axial dispersion coefficient from available correlations versus obtaining both it and mass transfer information from experimental breakthrough data and the consequences that may arise when doing so based on using a 1-D axially dispersed plug flow model and its associated Danckwerts outlet boundary condition. These consequences mainly included determining the potential for erroneous extraction of the axial dispersion coefficient and/or the LDF mass transfer coefficient from experimental data, especially when nonplug flow conditions prevailed in the bed. Two adsorbent/adsorbate cases were considered, i.e., CO2 and H2O vapor in zeolite 5A, because they both experimentally exhibited significant nonplug flow behavior, and the H2O-zeolite 5A system exhibited unusual concentration front sharpening that destroyed the expected constant pattern behavior (CPB) when modeled with the 1-D axially dispersed plug flow model. Overall, this work showed that it was possible to extract accurate mass transfer and dispersion information from experimental breakthrough curves using a 1-D axial dispersed plug flow model when they were measured both inside and outside the bed. To ensure the extracted information was accurate, the inside the bed breakthrough curves and their derivatives from the model were plotted to confirm whether or not the adsorbate/adsorbent system was exhibiting CPB or any concentration front sharpening near the bed exit. Even when concentration front sharpening was occurring with the H2O-zeolite 5A system, it was still possible to use the experimental inside and outside the bed breakthrough curves to extract fundamental mass transfer and dispersion information from the 1-D axial dispersed plug flow model based on the systematic methodology developed in this work.

16.
BMC Res Notes ; 8: 260, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26109044

RESUMO

BACKGROUND: Chronic hepatitis C (CHC) is a global health challenge. New therapeutic agents with excellent sustained virological response (SVR) rates are available mainly in developed countries, while the majority of CHC patients live in countries with low health budget. Predictors of therapeutic response are therefore necessary. Vitamin B12 appears to be involved in hepatitis C virus replication. METHODS: We therefore studied retrospectively the relationship between baseline serum vitamin B12 levels and clinical features in 116 CHC genotype 1 infected patients. Logistic regression models with univariate and multivariate analysis were used in the statistical analysis. RESULTS: Baseline serum vitamin B12 levels were found to be positively associated with serum transaminase activities (AST, p = 0.002, ALT, p = 0.04), baseline viral load (p < 0.0001), stage of fibrosis (p = 0.0001) and favorable interferon-λ3/4 (IFNL3/IFNL4) rs12979860 genotypes (p = 0.04), and inversely with SVR (p < 0.001) as well as with rapid virological response (p = 0.001). Patients with baseline serum vitamin B12 levels below a cut-off value of 570 ng/L achieved a SVR rate of 59% with an odds ratio (OR) of 13.4 [confidence interval (CI) 4.3-41.9, p < 0.0001] compared to patients above the cut-off value. By combining serum vitamin B12 levels and IFNL3/IFNL4 rs12979860 genotypes, patients with baseline serum vitamin B12 levels below the cut-off value of 570 ng/L and IFNL3/IFNL4 rs12979860 CC genotype achieved a SVR rate of even 80% with an OR of 54 (CI 9.9-293, p < 0.0001) compared to patients above the cut-off value and non-CC-genotypes. CONCLUSION: Our data suggest baseline serum vitamin B12 levels as useful noninvasive marker for characterizing CHC patients. They might further help to identify responders to a standard treatment.


Assuntos
Genótipo , Hepacivirus/genética , Hepatite C Crônica/virologia , Cirrose Hepática/sangue , Vitamina B 12/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
17.
J Cancer Educ ; 30(4): 670-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25519250

RESUMO

As of January, 2012, an estimated 13.7 million persons are living as cancer survivors. This population is expected to grow to nearly 18 million by 2022. While their treatment may be considered successful, many cancer survivors experience long-term physical, emotional, and psychosocial late effects of treatment. Our focus was on community-based cancer care-both rural and urban-as almost 90% of cancer care occurs in community settings, where a full complement of supportive healthcare professionals may not be available. This study describes the results of stakeholder engagement and the feedback processes used to create NaviCanPlan, a mobile web resource locator designed to educate and inform both providers and survivors in finding health-related services, often in noncancer center settings. Individual interviews with survivors and providers regarding resource needs to address a variety of physical and psychosocial late effects were supplemented with site visits, web-based polling, and webinars discussions. Overall, the results indicated a need for a programmatic approach to providing education about community, medical, and nonmedical resources for providers and survivors. Design and content criteria for a web-based mobile resource locator were defined, articulated, and implemented.


Assuntos
Pessoal de Saúde/educação , Recursos em Saúde , Armazenamento e Recuperação da Informação/métodos , Internet/estatística & dados numéricos , Neoplasias/psicologia , Neoplasias/terapia , Sobreviventes/psicologia , Necessidades e Demandas de Serviços de Saúde , Humanos , Telemedicina
18.
Pediatr Transplant ; 18(8): 839-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25283839

RESUMO

IL-2RA are frequently used as induction therapy in liver transplant recipients to decrease the risk of AR while allowing the reduction of concomitant immunosuppression. The exact association with the use of IL-2RA, however, is uncertain. We performed a systematic literature search for relevant studies. Random effects models were used to assess the incidence of AR, steroid-resistant rejection, graft loss, patient death, and adverse drug reaction, with or without IL-2RA. Six studies (two randomized and four non-randomized) met the eligibility criteria. Acute rejection at six months or later favored the use of IL-2RA significantly (RR 0.38; 95% CI 0.22-0.66, p = 0.0005). Although not statistically significant, IL-2RA showed a substantial reduction of the risk of steroid-resistant rejection (RR 0.32; CI 0.19-1.03, p = 0.0594). Graft loss and patient death showed a reductive tendency through the use of IL-2RA. The use of IL-2RA is safe and is associated with a statistically significantly lower incidence of AR after transplantation and substantial reduction of steroid-resistant rejection, graft loss, and patient death.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Imunoglobulina G/uso terapêutico , Imunossupressores/uso terapêutico , Transplante de Fígado , Receptores de Interleucina-2/antagonistas & inibidores , Proteínas Recombinantes de Fusão/uso terapêutico , Basiliximab , Criança , Ensaios Clínicos Controlados como Assunto , Daclizumabe , Sobrevivência de Enxerto , Humanos , Modelos Estatísticos , Resultado do Tratamento
19.
BMC Infect Dis ; 14: 503, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25227310

RESUMO

BACKGROUND: A decline in hemoglobin (Hb) concentration during antiviral therapy in chronic hepatitis C (CHC) is a serious side effect. It may compel to dose reduction or even termination of antiviral treatment. The activation of erythropoietin (EPO) synthesis as a physiological response to anemia and its relation to a genetic variation within the EPO gene has not been evaluated yet. METHODS: Data of 348 CHC patients were reviewed retrospectively. Samples were genotyped for EPO rs1617640 and inosine triphosphatase (ITPA) rs1127354. Serum EPO concentrations were determined before and during therapy. Primary endpoints were set as Hb decline >3 g/dl at weeks 4 and 12. RESULTS: EPO rs1617640 G homozygotes showed a significantly lower rise of serum EPO level over time than T allele carriers (p < 0.001). The cumulative frequency of a significant Hb reduction added up to 40%. Multivariate analysis revealed that besides age, ribavirin starting dose and baseline Hb also EPO rs1617640 G homozygosity associates with Hb reduction at week 4 (p = 0.025) and 12 (p = 0.029), while ITPA C homozygotes are at risk for Hb decline particularly early during treatment. Furthermore, EPO rs1617640 G homozygotes were more frequently in need for blood transfusion, epoetin-α supplementation, or ribavirin dose reduction (p < 0.001). CONCLUSIONS: Our data suggest that EPO rs1617640 genotype, the rise of serum EPO concentration as well as ITPA rs1127354 genotype are promising parameters to evaluate the Hb decline during antiviral therapy. A rational adjustment of therapy with epoetin-α supplementation might prevent serious adverse events or the need to terminate treatment.


Assuntos
Antivirais/uso terapêutico , Regulação para Baixo , Eritropoetina/sangue , Eritropoetina/genética , Hemoglobinas/metabolismo , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Epoetina alfa , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Pirofosfatases/genética , Pirofosfatases/metabolismo , Proteínas Recombinantes , Estudos Retrospectivos , Ribavirina/uso terapêutico , Resultado do Tratamento
20.
BMC Gastroenterol ; 13: 148, 2013 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-24118976

RESUMO

BACKGROUND: Telaprevir (TVR) has been approved for response-guided-therapy (RGT) of chronic hepatitis C (HCV) genotype-1-infection in treatment-naïve and -experienced patients. In RGT-regimens patients that did not achieve extended rapid-virological-response (eRVR) within the first 4-12 weeks undergo treatment for 48-weeks, whereas in fixed-length-treatment (FLT) patients are treated for a fixed-duration regardless of their RVR. METHODS: This systematic review and Bayesian mixed-treatment-comparison (MTC) aimed to compare the efficacy and safety of standard-therapy with pegylated-interferon-α/ribavirin (Peg-IFN-α/RBV (48 weeks), group A), FLT with TVR, Peg-IFN-α/RBV for 12 weeks with a long (+36 weeks, group B) or short (+12 weeks, group C) tail of Peg-IFN-α/RBV treatment, and RGT with 12 weeks of TVR, Peg-IFN-α/RBV followed by 12 weeks of Peg-IFN-α/RBV (group D) or no therapy (group E). RESULTS: We identified seven randomized controlled trials including 3505 patients. Compared to standard-treatment (group A), treatment-naïve patients allocated to groups B, C, and D were significantly more likely to achieve sustained-virological-response (SVR, odds ratios (OR): B vs. A 3.5 (credibility interval [CrI] 2.2-5.4), C vs. A 3.0 (CrI 1.8-4.9), D vs. A 3.4 (CrI 2.5-4.6)). Treatment-experienced patients achieved increased SVR rates when they were treated in group B (OR: 8.2 (CrI 5.0-13.5)), C (OR 7.0 (CrI 3.9-12.8)), or simulated group D (OR 8.2 (CrI 4.3-15.3)). Patients treated with short RGT (simulated group E) did also have a significant improvement when they were treatment-experienced (simulated OR 3.6 (CrI 1.6-8.2)), whereas the effect was not significant in treatment-naïve patients (OR E vs. A 1.6 (CrI 0.9-2.7)). CONCLUSION: Long FLT and RGT regimens are useful treatment options for HCV-genotype-1 in both treatment-naïve and -experienced patients. A short 24-weeks FLT regimen does not seem to be inferior and should further be evaluated in clinical trials to reduce side effects and costs of treatment.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Antivirais/uso terapêutico , Teorema de Bayes , Quimioterapia Combinada , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Resultado do Tratamento
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