Citations

Renal function and blood flow decline during aging in association with a decrease in the number of intrarenal vessels, but if loss of estrogen contributes to this microvascular, rarefaction remains unclear. We tested the hypothesis that the decreased renal microvascular density with age is aggravated by loss of estrogen. Six-month-old female C57/BL6 mice underwent ovariectomy (Ovx) or sham operation and then were allowed to age to 18–22 mo. Another comparable group was replenished with estrogen after Ovx (Ovx+E), while a 6-mo-old group served as young controls. Kidneys were then dissected for evaluation of microvascular density (by micro-computed tomography) and angiogenic and fibrogenic factors. Cortical density of small microvessels (20–200 μm) was decreased in all aged groups compared with young controls (30.3 ± 5.8 vessels/mm2, P < 0.05), but tended to be lower in sham compared with Ovx and Ovx+E (9.9 ± 1.7 vs. 17.2 ± 4.2 and 18 ± 3.0 vessels/mm2, P = 0.08 and P = 0.02, respectively). Cortical density of larger microvessels (200–500 μm) decreased only in aged sham ( P = 0.04 vs. young control), and proangiogenic signaling was attenuated. On the other hand, renal fibrogenic mechanisms were aggravated in aged Ovx compared with aged sham, but blunted in Ovx+E, in association with downregulated transforming growth factor-β signaling and decreased oxidative stress in the kidney. Therefore, aging induced in female mice renal cortical microvascular loss, which was likely not mediated by loss of endogenous estrogen. However, estrogen may play a role in protecting the kidney by decreasing oxidative stress and attenuating mechanisms linked to renal interstitial fibrosis.

Background: Fresh-stored osteochondral allografts have been used successfully to resurface large chondral and osteochondral defects of the knee. However, there are limited data available for the return to athletic activity. Purpose: To review the rate of return to athletic activity after osteochondral allograft transplantation in the knee and to identify any potential risk factors for not returning to sport. Study Design: Case series; Level of evidence, 4. Methods: Forty-three athletes were treated with fresh-stored osteochondral allograft transplantation for symptomatic large chondral or osteochondral defects of the knee from 2000 to 2010. The average age of the athletes (30 men, 13 women) was 32.9 years (range, 18-49 years). Patients were prospectively evaluated by International Knee Documentation Committee (IKDC), activities of daily living scale of the Knee Injury and Osteoarthritis Outcome Score (KOOS), Marx Activity Rating Scale, and Cincinnati Sports Activity Scale scores. A multivariable regression analysis was performed to identify potential risk factors for failure to return to sport at the preinjury level. Results: At an average 2.5-year follow-up, limited return to sport was possible in 38 of 43 athletes (88%), with full return to the preinjury level achieved in 34 of 43 athletes (79%). In these 34 athletes, time to return to sport was 9.6 ± 3.0 months. Age ≥25 years ( P = .04) and preoperative duration of symptoms greater than 12 months (odds ratio, 37; P = .003) negatively affected the ability to return to sport. In the athletes who returned to their previous level of competition, IKDC ( P < .001), KOOS ( P = .02), and Marx Activity Rating Scale ( P < .001) scores were all significantly greater than in those athletes who did not return to sport. Conclusion: Osteochondral allograft transplantation in an athletic population for chondral and osteochondral defects in the knee allows for a high rate of return to sport. Risk factors for not returning to sport included age ≥25 years and preoperative duration of symptoms ≥12 months.

Glioblastoma, the most common primary malignant cancer of the brain, is characterized by rapid tumor growth and infiltration of tumor cells throughout the brain. These traits cause glioblastomas to be highly resistant to current therapies with a resultant poor prognosis. Although aberrant oncogenic signaling driven by signature genetic alterations, such as EGF receptor (EGFR) gene amplification and mutation, plays a major role in glioblastoma pathogenesis, the responsible downstream mechanisms remain less clear. Here, we report that EGFRvIII (also known as ΔEGFR and de2-7EGFR), a constitutively active EGFR mutant that is frequently co-overexpressed with EGFR in human glioblastoma, promotes tumorigenesis through Src family kinase (SFK)-dependent phosphorylation of Dock180, a guanine nucleotide exchange factor for Rac1. EGFRvIII induces phosphorylation of Dock180 at tyrosine residue 722 (Dock180 Y722 ) and stimulates Rac1-signaling, glioblastoma cell survival and migration. Consistent with this being causal, siRNA knockdown of Dock180 or expression of a Dock180 Y722F mutant inhibits each of these EGFRvIII-stimulated activities. The SFKs, Src, Fyn, and Lyn, induce phosphorylation of Dock180 Y722 and inhibition of these SFKs by pharmacological inhibitors or shRNA depletion markedly attenuates EGFRvIII-induced phosphorylation of Dock180 Y722 , Rac1 activity, and glioblastoma cell migration. Finally, phosphorylated Dock180 Y722 is coexpressed with EGFRvIII and phosphorylated Src Y418 in clinical specimens, and such coexpression correlates with an extremely poor survival in glioblastoma patients. These results suggest that targeting the SFK-p-Dock180 Y722 -Rac1 signaling pathway may offer a novel therapeutic strategy for glioblastomas with EGFRvIII overexpression.

Abstract Background: Genetic influences may be discerned in families that have multiple affected members and may manifest as an earlier age of cancer diagnosis. In this study, we determine whether cancers develop at an earlier age in multiplex Familial Barrett's Esophagus (FBE) kindreds, defined by 3 or more members affected by Barrett's esophagus (BE) or esophageal adenocarcinoma (EAC). Methods: Information on BE/EAC risk factors and family history was collected from probands at eight tertiary care academic hospitals. Age of cancer diagnosis and other risk factors were compared between nonfamilial (no affected relatives), duplex (two affected relatives), and multiplex (three or more affected relatives) FBE kindreds. Results: The study included 830 nonfamilial, 274 duplex, and 41 multiplex FBE kindreds with 274, 133, and 43 EAC and 566, 288, and 103 BE cases, respectively. Multivariable mixed models adjusting for familial correlations showed that multiplex kindreds were associated with a younger age of cancer diagnosis (P = 0.0186). Median age of cancer diagnosis was significantly younger in multiplex compared with duplex and nonfamilial kindreds (57 vs. 62 vs. 63 years, respectively, P = 0.0448). Mean body mass index was significantly lower in multiplex kindreds (P = 0.0033), as was smoking (P &lt; 0.0001), and reported regurgitation (P = 0.0014). Conclusions: Members of multiplex FBE kindreds develop EAC at an earlier age compared with nonfamilial EAC cases. Multiplex kindreds do not have a higher proportion of common risk factors for EAC, suggesting that this aggregation might be related to a genetic factor. Impact: These findings indicate that efforts to identify susceptibility genes for BE and EAC will need to focus on multiplex kindreds. Cancer Epidemiol Biomarkers Prev; 21(2); 376–83. ©2011 AACR.

Abstract Background: Increasing colorectal cancer screening (CRCS) is important for attaining the Healthy People 2020 goal of reducing CRC-related morbidity and mortality. Evaluating CRCS trends can help identify shifts in CRCS, and specific groups that might be targeted for CRCS. Methods: We utilized medical records to describe population-based adherence to average-risk CRCS guidelines from 1997 to 2008 in Olmsted County, MN. CRCS trends were analyzed overall and by gender, age, and adherence to screening mammography (women only). We also carried out an analysis to examine whether CRCS is being initiated at the recommended age of 50. Results: From 1997 to 2008, the size of the total eligible sample ranged from 20,585 to 21,468 people. CRCS increased from 22% to 65% for women and from 17% to 59% for men (P &lt; 0.001 for both) between 1997 and 2008. CRCS among women current with mammography screening increased from 26% to 74%, and this group was more likely to be adherent to CRCS than all other subgroups analyzed (P &lt; 0.001).The mean ages of screening initiation were stable throughout the study period, with a mean age of 55 years among both men and women in 2008. Conclusion: Although overall CRCS tripled during the study period, there is still room for improvement. Impact: Working to decrease the age at first screening, exploration of gender differences in screening behavior, and targeting women adherent to mammography but not to CRCS seem warranted. Cancer Epidemiol Biomarkers Prev; 21(2); 347–50. ©2011 AACR.

Background and objectives: Pregnancies in women with systemic lupus erythematosus (SLE) and lupus nephritis are considered high-risk due to high rates of maternal and fetal complications. However, there has not been a formal analysis addressing the issue of maternal deaths in these women. The aim of this study was to perform a literature review of the maternal deaths in women with SLE and lupus nephritis to: (1) identify the main causes of death and (2) discuss possible reasons for these causes, and strategies that may improve patient care and outcomes. Design, setting, participants, and measurement: We performed an extensive electronic literature search from 1962 to 2009 using online databases (PubMed, Embase, Lilacs, Cochrane Controlled Trials Register, Medline, and Science Citation Index). Studies were included if they reported pregnancies in patients with SLE and lupus nephritis with at least one reported maternal death. Results: We identified 13 studies that reported a total of 17 deaths in the 6 week post-partum period that were attributable to SLE and lupus nephritis. In all cases, death occurred in the setting of active disease, and was attributed either to infection in 41.2% ( n = 7), or disease activity in 29.4% ( n = 5). The remaining deaths were due to pulmonary embolus in 11.8% ( n = 2), pregnancy-associated cardiomyopathy in 5.9% ( n = 1), adrenal failure due to abrupt steroid withdrawal in 5.9% ( n = 1), and undefined in 5.9% ( n = 1). Conclusions: All maternal deaths in patients with SLE and lupus nephritis occurred in those with active disease, with disease activity/complications and infections (mainly opportunistic) being the two major causes. The presented evidence further supports timing of pregnancy relative to SLE activity, and the judicious use of immunosuppressive agents in pregnant patients.

Recent studies have demonstrated that the function of glia is not restricted to the support of neuronal function. Especially, astrocytes are essential for neuronal activity in the brain. Astrocytes actively participate in synapse formation and brain information processing by releasing or uptaking gliotransmitters such as glutamate, d ‐serine, adenosine 5′‐triphosphate ( ATP ), and adenosine. In the central nervous system, adenosine plays an important role in regulating neuronal activity as well as in controlling other neurotransmitter systems such as GABA , glutamate, and dopamine. Ethanol ( E t OH ) increases extracellular adenosine levels, which regulates the ataxic and hypnotic/sedative (somnogenic) effects of E t OH . Adenosine signaling is also involved in the homeostasis of major inhibitory/excitatory neurotransmission (i.e., GABA or glutamate) through neuron–glial interactions, which regulates the effect of E t OH and sleep. Adenosine transporters or astrocytic SNARE ‐mediated transmitter release regulates extracellular or synaptic adenosine levels. Adenosine then exerts its function through several adenosine receptors and regulates glutamate levels in the brain. This review presents novel findings on how neuron–glial interactions, particularly adenosinergic signaling and glutamate uptake activity involving glutamate transporter 1 ( GLT 1), are implicated in alcoholism and sleep disorders.