17 research outputs found
Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts
Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007).
Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold.
The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates.
Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants.
The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances
Verrucomicrobial community structure and abundance as indicators for changes in chemical factors linked to soil fertility
How students cope with part-time study: An analysis of coping mechanisms through an on-line forum
This study provides a qualitative test and illustration of a model of how students cope with the demands of part-time study. The model shows that students who are successful in finding the time to complete the requirements of part-time courses do so by adopting three mechanisms; sacrifice, support and the negotiation of arrangements. All three mechanisms operate in four domains, namely work, family, social lives and the self. The mechanisms and domains were related together in a three by four matrix. Data to verify and illuminate the model were gathered by the researchers through an on-line forum discussion on the topic of coping with part-time study. The researchers themselves were studying part-time in a course called Adult Education and Professional Development. Analysis of the data showed that the work domain was very important but little adaptation was possible. The family was seen as the most important domain and all three mechanisms were used. Time was commonly found for part-time study by sacrificing social lives. The self-domain was interpreted as important in establishing motivation and self-determination
Friends, Depressive Symptoms, and Life Satisfaction Among Older Korean Americans
Click on the DOI link to access the article (may not be free).This study examined the interactive effects of social network support and depressive symptoms on life satisfaction among older Korean Americans (KAs). Using data from a sample of 200 elders in a large metropolitan area (M (age) = 72.50, SD = 5.15), hierarchical regression analysis was used to examine the interaction between social network support and depressive symptoms on life satisfaction among older KAs. After controlling for demographic variables, both social network support and depressive symptoms were identified as predictors for life satisfaction. Interaction effects indicated strong associations between higher social network support specifically from friends and lower depressive symptoms with higher levels of life satisfaction. Findings highlight the important role that friends play in terms of social network support for the mental health of older KAs, and the need for geriatric practitioners to monitor and assess the quality of social network support-including friendships-when working with older KAs
Antitumor activity of bintrafusp alfa in previously treated patients with recurrent or metastatic nasopharyngeal cancer (NPC): A single arm, prospective phase II trial.
e18029 Background: Patients with recurrent or metastatic nasopharyngeal cancer (R/M NPC) who failed platinum-based chemotherapy have poor prognoses. We report the clinical activity and safety of bintrafusp alfa, a first-in-class bifunctional fusion protein composed of the extracellular domain of the transforming growth factor (TGF)-βRII receptor fused to a human IgG1 antibody blocking programmed death-ligand 1 (PD-L1), in patients with heavily pretreated R/M NPC. Tumor and plasma-based biomarkers were investigated in an exploratory analysis. Methods: Eligible patients had histologically confirmed NPC that had recurred at distant sites and were not amenable to curative treatment. All patients received at least one prior line of platinum-based chemotherapy for recurrent disease. Patients were treated with bintrafusp alfa (1200mg every 2 weeks) until disease progression. The sample size was estimated to assume a 40% objective response rate (ORR) to bintrafusp alfa compared with 20% for checkpoint inhibitors. Modified Simon two-stage optimal design was used (power, 80%; a = 0.05; P0 = 0.20; P1 = 0.40; n1 = 18; n = 33 with an additional five patients to allow for ineligibility or other reasons). The primary endpoint was ORR and secondary endpoints included survival and toxicity. Expression of PD-L1 in archived tumors, plasma clearance of Epstein-Barr virus (EBV) DNA, plasma clearance of TGF-β, and exosomal PD-L1 were assessed for a potential correlation with ORR. (NCT 04396886). Results: Out of 43 patients screened, 38 patients were enrolled. After a median follow-up of 14.9 months (range: 1.6-23.3 months), the confirmed ORR was 23.7% (95% CI: 12.4-38.8%) (complete response, n = 1; partial response, n = 8). The median treatment duration was 1.8 months (range: 0.5-14.3 months). 8 patients (21.1%) and 2 patients (5.3%) received bintrafusp alfa for > 6 months and > 12 months respectively. The 1-year overall survival (OS) rate was 57.5% (95% CI, 40.2% to 71.5%) and 1-year progression-free survival rate was 23% (95% CI, 10.1% to 39.4%). ORR was higher in patients with a decreasing trend in EBV-DNA at week 4 (40% vs. 6.3%, p = 0.02), whereas high exosomal PD-L1 levels at week 4 were predictive of worse ORR (5.3% vs. 41.7%, p = 0.012). There were no associations between clinical outcome and tissue PD-L1 expression (p = 0.952) or plasma TGF-β clearance (p = 0.28). 16 patients (42.4%) experienced ≥ grade 3 treatment-related adverse events, most commonly anemia (n = 9, 23.7%) and secondary malignancies (n = 4, 10.5%). Conclusions: Bintrafusp alfa has promising activity in heavily pretreated R/M NPC and a favorable 1-year OS rate, though the observed activity was not as high as the study initially aimed. The biomarker results warrant validation in larger cohorts. Clinical trial information: NCT04396886. </jats:p
