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61.
PurposeTo compare outcomes of unresectable hepatocellular-cholangiocarcinoma (HCC-CC) with hepatocellular carcinoma (HCC) after locoregional therapy (LRT).Materials and MethodsConsecutive patients with histologically confirmed HCC-CC or HCC treated with LRT between 2007 and 2017 were retrospectively reviewed. Ten patients (8 men; median age, 60 y) with 12 HCC-CCs (mean diameter, 4.2 cm ± 1.9; mean number, 3.7 ± 3.3) treated with chemoembolization (n = 6), yttrium-90 radioembolization (n = 2), RF ablation (n = 1), or chemoembolization/RF ablation (n = 1) were compared with 124 patients (92 men; median age, 59 y) with 134 HCCs (mean diameter, 4.8 cm ± 4.0; mean number, 2.6 ± 2.2) treated with chemoembolization (n = 51), yttrium-90 radioembolization (n = 17), RF ablation (n = 41), or chemoembolization/RF ablation (n = 15). Propensity score–matched analysis with conditional logistic regression adjusted for age, sex, LRT modality, tumor-specific features, and Child-Pugh class. Tumor-volume doubling time (TVDT) before LRT and objective response rates were compared by Kruskal-Wallis and Fisher exact test; progression-free survival (PFS) and transplant-free survival (TFS) were compared by Cox proportional hazards model.ResultsOn univariate analysis, HCC-CC was associated with lower median TVDT (2.4 months vs 5.2 months, P = .03), objective response (30% vs 71%, P = .01), and median PFS (2.4 months vs 7.4 months, HR 4.3, 95% CI 2.2–8.4, P < .0001). Propensity score–matched analysis demonstrated greater distant progression (60% vs 30%, P = .003) and significantly shorter median PFS (2.4 months vs 6.0 months, HR 3.3, 95% CI 1.3–8.9, P = .017) for HCC-CC. No significant difference was observed in TFS (7.5 months vs 13.8 months, HR 1.5, 95% CI 0.4–6.1).ConclusionsHCC-CC was associated with reduced PFS and greater distant progression after LRT compared with HCC, indicating a need for adjunctive treatment strategies to improve outcomes.  相似文献   
62.
Chronic lymphocytic thyroiditis characterized by multifocal follicular lymphoid cell infiltrates with germinal centers, thyroid acinar atrophy and pituitary cell hyperplasia/hypertrophy of the adenohypophysis was detected in a vehicle control, 4-year-old female Cynomolgus macaque in a routine toxicology study. Lymphoid cells of germinal centers were positive for the B-cell marker CD20 by immunohistochemistry (IHC), while remaining lymphocytes were positive for the T-cell marker CD3. Hypertrophied/hyperplastic pituitary cells were positive for thyroid stimulating hormone (TSH) by IHC, consistent with an adaptive response due to removal of hormonal negative feedback from the diseased thyroid gland. Features of this case are similar to chronic lymphocytic thyroiditis in humans, an autoimmune disorder also known as Hashimoto's disease. Chronic lymphocytic thyroiditis with compensatory pituitary changes may occur spontaneously in young, clinically normal cynomolgus macaques and its presence in drug treated animals should be interpreted with caution.  相似文献   
63.
K-edge digital subtraction angiography (KEDSA), a recently developed synchrotron-based technique, utilizes monochromatic radiation and allows acquisition of high-quality angiography images after intravenous administration of contrast agent. We tested KEDSA for its suitability for intravenous cerebral angiography in an animal model. Adult male New Zealand rabbits were subjected to either angiography with conventional x-ray equipment or synchrotron-based intravenous KEDSA, using an iodine-based contrast agent. Angiography with conventional x-ray equipment after intra-arterial administration of contrast agent demonstrated the major intracranial vessels but no smaller branches. KEDSA was able to visualize the major intracranial vessels as well as smaller branches in both radiography mode (planar images) and tomography mode. Visualization was achieved with as little as 0.5 ml kg-1 of iodinated contrast material. We were able to obtain excellent visualization of the cerebral vasculature in an animal model using intravenous injection of contrast material, using synchrotron-based KEDSA.  相似文献   
64.
Context: Cardiovascular disease (CVD) is the number one cause of death globally, responsible for over 17 million (31%) deaths in the world. Novel pharmacological interventions may be needed given the high prevalence of CVD.

Objective: In this study, we aimed to find potential new sources of cardiovascular (CV) drugs from phylogenetic and pharmacological analyses of plant species that have experimental and traditional CV applications in the literature.

Materials and methods: We reconstructed the molecular phylogeny of these plant species and mapped their pharmacological mechanisms of action on the phylogeny.

Results: Out of 139 plant species in 71 plant families, seven plant families with 45 species emerged as phylogenetically important exhibiting common CV mechanisms of action within the family, as would be expected given their common ancestry: Apiaceae, Brassicaceae, Fabaceae, Lamiaceae, Malvaceae, Rosaceae and Zingiberaceae. Apiaceae and Brassicaceae promoted diuresis and hypotension; Fabaceae and Lamiaceae had anticoagulant/thrombolytic effects; Apiaceae and Zingiberaceae were calcium channel blockers. Moreover, Apiaceae, Lamiaceae, Malvaceae, Rosaceae and Zingiberaceae species were found to possess anti-atherosclerotic properties.

Discussion and conclusions: The phylogeny identified certain plant families with disproportionately more species, highlighting their importance as sources of natural products for CV drug discovery. Though there were some species that did not show the same mechanism within the family, the phylogeny predicts that these species may contain undiscovered phytochemistry, and potentially, the same bioactivity. Evolutionary pharmacology, as applied here, may guide and expedite our efforts in discovering sources of new CV drugs.  相似文献   

65.
Ebel  Florian  Greuter  Ladina  Guzman  Raphael  Soleman  Jehuda 《Neurosurgical review》2022,45(5):3109-3118
Neurosurgical Review - The development of minimally invasive neuroendoscopy has advanced in recent years. The introduction of the neuroendoscopic ultrasonic aspirator (NUA) increased the treatment...  相似文献   
66.
67.
GeroScience - Immunostimulation by chronic infection has been linked to an increased risk for different non-communicable diseases, which in turn are leading causes of death in high- and...  相似文献   
68.
Neonatal hypoxic–ischemic insults are a significant cause of pediatric encephalopathy, developmental delays, and spastic cerebral palsy. Although the developing brain’s plasticity allows for remarkable self-repair, severe disruption of normal myelination and cortical development upon neonatal brain injury are likely to generate life-persisting sensory-motor and cognitive deficits in the growing child. Currently, no treatments are available that can address the long-term consequences. Thus, regenerative medicine appears as a promising avenue to help restore normal developmental processes in affected infants. Stem cell therapy has proven effective in promoting functional recovery in animal models of neonatal hypoxic–ischemic injury and therefore represents a hopeful therapy for this unmet medical condition. Neural stem cells derived from pluripotent stem cells or fetal tissues as well as umbilical cord blood and mesenchymal stem cells have all shown initial success in improving functional outcomes. However, much still remains to be understood about how those stem cells can safely be administered to infants and what their repair mechanisms in the brain are. In this review, we discuss updated research into pathophysiological mechanisms of neonatal brain injury, the types of stem cell therapies currently being tested in this context, and the potential mechanisms through which exogenous stem cells might interact with and influence the developing brain.  相似文献   
69.
Tatton-Brown-Rahman syndrome (TBRS) is an overgrowth disorder caused by germline heterozygous mutations in the DNA methyltransferase DNMT3A. DNMT3A is a critical regulator of hematopoietic stem cell (HSC) differentiation and somatic DNMT3A mutations are frequent in hematologic malignancies and clonal hematopoiesis. Yet, the impact of constitutive DNMT3A mutation on hematopoiesis in TBRS is undefined. In order to establish how constitutive mutation of DNMT3A impacts blood development in TBRS we gathered clinical data and analyzed blood parameters in 18 individuals with TBRS. We also determined the distribution of major peripheral blood cell lineages by flow cytometric analyses. Our analyses revealed non-anemic macrocytosis, a relative decrease in lymphocytes and increase in neutrophils in TBRS individuals compared to unaffected controls. We were able to recapitulate these hematologic phenotypes in multiple murine models of TBRS and identified rare hematological and non-hematological malignancies associated with constitutive Dnmt3a mutation. We further show that loss of DNMT3A in TBRS is associated with an altered DNA methylation landscape in hematopoietic cells affecting regions critical to stem cell function and tumorigenesis. Overall, our data identify key hematopoietic effects driven by DNMT3A mutation with clinical implications for individuals with TBRS and DNMT3A-associated clonal hematopoiesis or malignancies.  相似文献   
70.
Of 379 severe acute respiratory syndrome coronavirus 2 samples collected in New York, USA, we detected 86 Omicron variant sequences containing Delta variant mutation P681R. Probable explanations were co-infection with 2 viruses or contamination/amplification artifact. Repeated library preparation with fewer cycles showed the P681R calls were artifactual. Unusual mutations should be interpreted with caution.  相似文献   
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