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In advanced breast cancer, biomarker identification and patient selection using a metastatic tumor biopsy is becoming more necessary. However, the biology of metastasis according to the organ site is largely unknown. Here, we evaluated the expression of 771 genes in 184 metastatic samples across 11 organs, including liver, lung, brain, and bone, and made the following observations. First, all PAM50 molecular intrinsic subtypes were represented across organs and within immunohistochemistry‐based groups. Second, HER2‐low disease was identified across all organ sites, including bone, and HER2 expression significantly correlated with ERBB2 expression. Third, the majority of expression variation was explained by intrinsic subtype and not organ of metastasis. Fourth, subtypes and individual subtype‐related genes/signatures were significantly associated with overall survival. Fifth, we identified 74 genes whose expression was organ‐specific and subtype‐independent. Finally, immune profiles were found more expressed in lung compared to brain or liver metastasis. Our results suggest that relevant tumor biology can be captured in metastatic tissues across a variety of organ sites; however, unique biological features according to organ site were also identified and future studies should explore their implications in diagnostic and therapeutic interventions.  相似文献   
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Parathyroid hormone-related protein (PTHrP) is an important modulator of bone formation. Recently, we reported that PTHrP (107-111) (osteostatin) coating onto mesoporous ceramics confers osteogenic activity to these materials. Bone repair is dramatically compromised in osteopenia/osteoporosis. Thus, we examined the efficacy of unmodified and organically modified SBA15 ceramics loaded with osteostatin in promoting bone repair in an osteoporotic rabbit model. Osteoporosis was induced in New Zealand rabbits by methylprednisolone administration, and healthy rabbits were used as controls. Tested materials were implanted into a femoral cavitary defect, and animals were sacrificed at 2 weeks post-implantation. At this time, implants were encapsulated by a variable layer of fibrotic tissue with no evidence of inflammation. Similarly to observations in normal rabbits, both types of osteostatin-loaded bioceramics induced tissue regeneration associated with increased staining for PCNA, Runx2, osteopontin, and/or vascular endothelial growth factor in osteoporotic rabbits. Our present findings demonstrate that these osteostatin-bearing bioceramics increase the early repair response not only in normal bone but also in osteoporotic bone after a local injury.  相似文献   
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The immune mechanisms in response to Chlamydophila abortus (Chlamydia psittaci serotype 1) infection were studied in C57BL/6 and CBA mice. The infection was monitored and the following aspects of the immune response were evaluated: the nature of the leucocyte infiltrate in the liver, the percentages of polymorphonuclear neutrophils (PMNs), macrophages and lymphocytes in the spleen, and the concentrations of cytokines in serum. In addition, the serum concentrations of IgG1 and IgG2a were determined. Both mouse strains showed a Th1-like immune response, with high concentrations of IFN-gamma and minimal levels of IL-4; however, C57 mice differed from CBA mice in showing milder clinical signs and earlier resolution of infection. The greater ability of C57 mice than CBA mice to eliminate chlamydophilae was related to the establishment of an earlier innate immunity, based on a more pronounced PMN response, and on a greater presence of CD8(+)T cells.  相似文献   
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The histologic findings of 325 necropsies of rheumatic patients at the National Institute of Cardiology in Mexico, between 1980-1985 were studied forty five of them had Aschoff nodules plus valvular inflammation-Out of these 45 cases two groups were formed: children-adolescent group (24 cases) and an adult group (21 cases). The clinical, histologic and laboratory findings were compared. Clinical records were reviewed searching for history of rheumatic fever. Active rheumatic fever was suspected in 16 patients in the younger group (67%) and only in 3 adults (14.2%). As far as Jones' criteria is concerned, the most common finding was carditis, principally in the younger group (83%). In the adult group, it appeared in 50% of the patients. All other criteria were only occasionally seen or could not be identified during the patients lifetime. The most common laboratory finding which could suggest active rheumatic fever were: a high levels of anti-streptolysin in younger patients (95%) and elevation of erythro-sedimentation in adults (83%). We conclude that in active rheumatic fever of the adult; Jones criteria are not met, so the illness is difficult to recognize, and there is clinical-histologic discrepancy. In this context the disease has a "silent" evolution.  相似文献   
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IntroductionThe increased risk of myocardial infarction (MI) in type 2 diabetes mellitus (T2DM) is well documented. Polymorphisms in APOA1 and APOB genes allow us to identify new genetic markers in the Mexican population with T2DM and MI.Material and methodsWe studied 135 patients with DMT2 and MI (DI); another 85 non-infarcted diabetic individuals with DMT2 but without previous ischemic events (NID) and 242 healthy subjects (HS). All three groups were selected with the aim to investigate the association between the polymorphisms and infarction when T2DM is present or absent.Results-75 G>A polymorphism: Differences were found in genotype distribution between DI and NID individuals (OR = 2.01, 95% CI: 1.117–3.623, p = 0.019) with an increased risk for A in the dominant model (OR = 1.77, 95% CI: 1.020–3.084, p = 0.042); also concentrations of ApoA-I for A/A were lower in comparison with G/A (p = 0.038) and LDL-C and HDL-C levels were lower in G/A compared to G/G carriers. 83 C>T polymorphism of APOA1: For DI individuals, HDL-C was lower in T/T compared to C/C and triglyceride levels were lower in C/T compared to C/C carriers.ConclusionsThe -75 G>A APOA1 polymorphism could be considered as a susceptibility factor for myocardial infarction in individuals with T2DM and 2488 C>T APOB polymorphism is associated with changes in HDL-C and LDL-C and triglycerides in the same group.  相似文献   
49.
Although baseline blood glucose levels in aged Fischer-344 rats are comparable to those of young rats, the rise in blood glucose in response to training-related stress is substantially attenuated. The diminished response may contribute to increased depletion of extracellular brain glucose levels during training in aged rats; the depletion is blocked and memory is enhanced by systemic injections of glucose. The present experiment examined the role of glucose in regulating memory for reward reduction training. Blood glucose levels exhibited a significant rise after reward reduction trials in young adult but not 2-year-old rats. Although young and aged rats exhibited comparable learning during the day of reward reduction training, aged rats exhibited more rapid forgetting of the learning response. Post-training glucose injections (200 mg/kg, i.p.) facilitated memory formation and slowed the rate of forgetting in young and old rats, consistent with the view that deficiencies in circulating glucose responses to training may contribute to the rapid forgetting evident in aged Fischer-344 rats.  相似文献   
50.
Allergic disorders are characterized by the involvement of allergen-specific immunoglobulin (Ig)E antibodies and T helper type 2 (Th2) cells. The search for new therapies for allergic diseases has been the primary focus of interest for many investigators in recent years. Glycomacropeptide (GMP) is a biologically active component of milk that exhibits a range of immunomodulatory functions. We examined whether oral administration of GMP could affect the development of allergic sensitization and the severity of immediate cutaneous hypersensitivity reactions and of anaphylaxis. Rats treated with or without GMP were ovalbumin (OVA)-sensitized and several indicators of allergy were evaluated. Pretreatment with GMP resulted in reduction of antigen-specific IgE titre in rats when sensitized with OVA. GMP administration also markedly suppressed the proliferative response of splenocytes to antigen and the production of interleukin (IL)-13 by splenocytes of sensitized animals. In addition, GMP pretreatment attenuated the intensity of the immediate cutaneous reaction induced by antigen and protected the sensitized rats from severe anaphylaxis. These data demonstrate, for the first time, that the administration of GMP prevents allergen sensitization and reduces the severity of the early-phase reaction induced by antigen in cutaneous hypersensitivity and in anaphylaxis. GMP may be used as a novel prophylactic agent for the control of allergic diseases.  相似文献   
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