9 research outputs found
Environmental risk factors for dementia: a systematic review
Background - Dementia risk reduction is a major and growing public health priority. While certain modifiable risk factors for dementia have been identified, there remains a substantial proportion of unexplained risk. There is evidence that environmental risk factors may explain some of this risk. Thus, we present the first comprehensive systematic review of environmental risk factors for dementia.
Methods - We searched the PubMed and Web of Science databases from their inception to January 2016, bibliographies of review articles, and articles related to publically available environmental data. Articles were included if they examined the association between an environmental risk factor and dementia. Studies with another outcome (for example, cognition), a physiological measure of the exposure, case studies, animal studies, and studies of nutrition were excluded. Data were extracted from individual studies which were, in turn, appraised for methodological quality. The strength and consistency of the overall evidence for each risk factor identified was assessed.
Results - We screened 4784 studies and included 60 in the review. Risk factors were considered in six categories: air quality, toxic heavy metals, other metals, other trace elements, occupational-related exposures, and miscellaneous environmental factors. Few studies took a life course approach. There is at least moderate evidence implicating the following risk factors: air pollution; aluminium; silicon; selenium; pesticides; vitamin D deficiency; and electric and magnetic fields.
Conclusions - Studies varied widely in size and quality and therefore we must be circumspect in our conclusions. Nevertheless, this extensive review suggests that future research could focus on a short list of environmental risk factors for dementia. Furthermore, further robust, longitudinal studies with repeated measures of environmental exposures are required to confirm these associations
Osteoclast-mediated resorption primes the skeleton for successful integration during axolotl limb regeneration.
Early events during axolotl limb regeneration include an immune response and the formation of a wound epithelium. These events are linked to a clearance of damaged tissue prior to blastema formation and regeneration of the missing structures. Here, we report the resorption of calcified skeletal tissue as an active, cell-driven, and highly regulated event. This process, carried out by osteoclasts, is essential for a successful integration of the newly formed skeleton. Indeed, the extent of resorption is directly correlated with the integration efficiency, and treatment with zoledronic acid resulted in osteoclast function inhibition and failed tissue integration. Moreover, we identified the wound epithelium as a regulator of skeletal resorption, likely releasing signals involved in recruitment/differentiation of osteoclasts. Finally, we reported a correlation between resorption and blastema formation, particularly, a coordination of resorption with cartilage condensation. In sum, our results identify resorption as a major event upon amputation, playing a critical role in the overall process of skeletal regeneration
Cloning, sequencing and function ofsanB, a gene related to nikkomycin biosynthesis ofStreptomyces ansochromogenes
Optimized axolotl (Ambystoma mexicanum) husbandry, breeding, metamorphosis, transgenesis and tamoxifen-mediated recombination
Primary brain tumours and specific serum immunoglobulin E: a case-control study nested in the European Prospective Investigation into Cancer and Nutrition cohort
Background: Case-control studies suggest that patients with allergic
diseases have a lower risk of developing glioma but not meningioma or
schwannoma. However, those data can be differentially biased.
Prospective studies with objective measurements of immunologic
biomarkers, like immunoglobulin E (IgE), in blood obtained before cancer
diagnosis could help to clarify whether an aetiological association
exists.
Methods: The present case-control study nested within the European
Prospective Investigation into Cancer and Nutrition (EPIC) measured
specific serum IgE as a biomarker for the most common inhalant allergens
in 275 glioma, 175 meningioma and 49 schwannoma cases and 963 matched
controls using the ImmunoCAP specific IgE test. Subjects with an IgE
level >= 0.35 kUA/l (kilo antibody units per litre) were classified as
sensitized by allergens. Odds ratios (OR) and 95% confidence intervals
(CI) were estimated by adjusted conditional logistic regression models
for each tumour subtype. The effect of dose-response relationship was
assessed in five increasing IgE level categories to estimate P-values
for trend.
Results: The risk of glioma was inversely related to allergic
sensitization (OR = 0.73; 95% CI 0.51-1.06), especially pronounced in
women (OR = 0.53; 95% CI 0.30-0.95). In dose-response analyses, for
high-grade glioma, the lowest OR was observed in sera with the highest
IgE levels (P for trend = 0.04). No association was seen for meningioma
and schwannoma.
Conclusion: The results, based on serum samples prospectively collected
in a cohort study, provide some support for the hypothesis that
individuals with allergic sensitization are at reduced risk of glioma
and confirm results from previous case-control studies
Brain tumour risk in relation to mobile telephone use: results of the INTERPHONE international case-control study
Methods An interview-based case-control study with 2708 glioma and 2409 meningioma cases and matched controls was conducted in 13 countries using a common protocol.
Results A reduced odds ratio (OR) related to ever having been a regular mobile phone user was seen for glioma [OR 0.81; 95% confidence interval (CI) 0.70-0.94] and meningioma (OR 0.79; 95% CI 0.68-0.91), possibly reflecting participation bias or other methodological limitations. No elevated OR was observed >= 10 years after first phone use (glioma: OR 0.98; 95% CI 0.76-1.26; meningioma: OR 0.83; 95% CI 0.61-1.14). ORs were = 1640 h, the OR was 1.40 (95% CI 1.03-1.89) for glioma, and 1.15 (95% CI 0.81-1.62) for meningioma; but there are implausible values of reported use in this group. ORs for glioma tended to be greater in the temporal lobe than in other lobes of the brain, but the CIs around the lobe-specific estimates were wide. ORs for glioma tended to be greater in subjects who reported usual phone use on the same side of the head as their tumour than on the opposite side.
Conclusions Overall, no increase in risk of glioma or meningioma was observed with use of mobile phones. There were suggestions of an increased risk of glioma at the highest exposure levels, but biases and error prevent a causal interpretation. The possible effects of long-term heavy use of mobile phones require further investigation