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101.

Aims/hypothesis

Impaired awareness of hypoglycaemia (IAH) in type 1 diabetes increases the risk of severe hypoglycaemia sixfold and can be resistant to intervention. We explored the impact of IAH on central responses to hypoglycaemia to investigate the mechanisms underlying barriers to therapeutic intervention.

Methods

We conducted [15O]water positron emission tomography studies of regional brain perfusion during euglycaemia (target 5 mmol/l), hypoglycaemia (achieved level, 2.4 mmol/l) and recovery (target 5 mmol/l) in 17 men with type 1 diabetes: eight with IAH, and nine with intact hypoglycaemia awareness (HA).

Results

Hypoglycaemia with HA was associated with increased activation in brain regions including the thalamus, insula, globus pallidus (GP), anterior cingulate cortex (ACC), orbital cortex, dorsolateral frontal (DLF) cortex, angular gyrus and amygdala; deactivation occurred in the temporal and parahippocampal regions. IAH was associated with reduced catecholamine and symptom responses to hypoglycaemia vs HA (incremental AUC: autonomic scores, 26.2?±?35.5 vs 422.7?±?237.1; neuroglycopenic scores, 34.8?±?88.8 vs 478.9?±?311.1; both p?<?0.002). There were subtle differences (p?<?0.005, k?≥?50 voxels) in brain activation at hypoglycaemia, including early differences in the right central operculum, bilateral medial orbital (MO) cortex, and left posterior DLF cortex, with additional differences in the ACC, right GP and post- and pre-central gyri in established hypoglycaemia, and lack of deactivation in temporal regions in established hypoglycaemia.

Conclusions/interpretation

Differences in activation in the post- and pre-central gyri may be expected in people with reduced subjective responses to hypoglycaemia. Alterations in the activity of regions involved in the drive to eat (operculum), emotional salience (MO cortex), aversion (GP) and recall (temporal) suggest differences in the perceived importance and urgency of responses to hypoglycaemia in IAH compared with HA, which may be key to the persistence of the condition.
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OBJECTIVE: To determine, over time, the rate and serotypes of pneumococci with reduced penicillin susceptibility obtained from children with invasive infection. DESIGN: Active, hospital-based, multicentre surveillance spanning from 1991 to 1998. SETTING: Eleven Canadian tertiary care paediatric facilities located from coast to coast. POPULATION STUDIED: 1847 children with invasive pneumococcal infection whose isolates (from a normally sterile site) were available for serotyping and standardized testing for penicillin susceptibility at the National Centre for Streptococcus. MAIN RESULTS: The prevalence of reduced penicillin susceptibility increased from 2.5% of 197 cases in 1991 to 13.0% of 276 cases in 1998. In the latter year, 8.7% of isolates had intermediate level resistance, and 4.3% had high level resistance. Since they were first detected in 1992, strains with high level resistance have been encountered only sporadically at most centres, but by 1998, all centres but two had encountered examples. Of 40 isolates with high level resistance and 101 isolates with intermediate level resistance, serotypes matched those included in new seven-valent conjugate vaccines for children in 97.5% and 79.2% of cases, respectively. CONCLUSIONS: Pneumococci with reduced susceptibility to penicillin are increasing in frequency across Canada among children with invasive infection. The Immunization Monitoring Program, Active data indicate that new conjugate vaccines could help to curb infections due to pneumococci with reduced susceptibility to penicillin but are unlikely to control completely the problem of antibiotic resistance.  相似文献   
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With the development and increasing accessibility of new genomic tools such as next-generation sequencing, genome-wide association studies, and genomic stratification models, the debate on genetic discrimination in the context of life insurance became even more complex, requiring a review of current practices and the exploration of new scenarios. In this perspective, a multidisciplinary group of international experts representing different interests revisited the genetics and life insurance debate during a 2-day symposium ‘Life insurance: breast cancer research and genetic risk prediction seminar'' held in Quebec City, Canada on 24 and 25 September 2012. Having reviewed the current legal, social, and ethical issues on the use of genomic information in the context of life insurance, the Expert Group identified four main questions: (1) Have recent developments in genomics and related sciences changed the contours of the genetics and life insurance debate? (2) Are genomic results obtained in a research context relevant for life insurance underwriting? (3) Should predictive risk assessment and risk stratification models based on genomic data also be used for life insurance underwriting? (4) What positive actions could stakeholders in the debate take to alleviate concerns over the use of genomic information by life insurance underwriters? This paper presents a summary of the discussions and the specific action items recommended by the Expert Group.Access to genetic information by life insurers has been a topic of discussion for many years.1 The possibility of using genetic data to underwrite an applicant''s insurance policy has given rise to concerns about the emergence of ‘genetic discrimination''. Genetic discrimination in the field of life insurance is not necessarily illegal in that in insurance underwriting questions about health, family history of disease, or genetic information may constitute legal exceptions to antidiscrimination legislation.2, 3 Nevertheless, the expression ‘genetic discrimination'' has acquired public notoriety4 and we will use more neutral language in this paper.Countries including Canada, the United States, Russia, and Japan5 have chosen not to adopt laws specifically prohibiting access to genetic data for underwriting by life insurers.6 In these countries, life insurance underwriters treat genetic data like other types of medical or lifestyle data. However, a growing number of countries such as Belgium, France, and Norway5 have chosen to adopt laws to prevent or limit insurers'' access to genetic data for life insurance underwriting. Other countries including Finland and the United Kingdom have developed voluntary arrangements with the industry (ie moratoria) with similar objectives.7Life insurance is a private contract between the policy-holder and the insurer. Its principal role is to provide financial security to the beneficiaries in the event of the insured''s death.8 Because of this important role, life insurance is often required, or strongly recommended for those seeking loans to acquire primary social goods, like housing or cars.9 In Europe, a consequence of the advent of the welfare state is that private insurance has increasingly played a complementary and supplementary role to social insurance by offering additional security and protection to the population. Thus, in this region, insurance is often considered as a social good that allows individuals to live a comfortable life and as a tool to promote social integration.10 In other regions of the world, this social role of life insurance is also recognized to a lesser extent. Given this social role, equitable access to life insurance is perceived as a sensitive issue and cases of denial looked upon negatively in popular media. Although documented incidents of denial or of increased premiums on the basis of genetic information have remained limited to the context of a few relatively well known, highly penetrant, familial, adult-onset, genetic conditions,11 they have nevertheless generated significant public concern. Fear that insurers will have access to genetic information generated in a clinical or research setting for use in underwriting has been reported by several studies as a reason for non-participation in genetic research or recommended clinical genetic testing.12, 13, 14The clinical utility of genetic testing for monogenic disorders such as Huntington disease, and hereditary forms of cancer are well established.15 However, genomic risk profiles based on the known common susceptibility variants have limited utility in risk prediction at the individual level, although they could be used for risk stratification in prevention programmes in populations.16 Today, a new era of genomic research has made it increasingly affordable to scan the entire genome of an individual. Researchers and physicians can interpret these data together with medical and lifestyle information in the form of sophisticated risk prediction models.17 Moreover, improvement in computing technologies coupled with the Internet make predictive information increasingly available, whether through direct-to-consumer marketing of genetic tests, genetic data sharing online communities, or international research database projects. Given these important technological and scientific changes, and their impact on various stakeholders. The term ‘stakeholders'' is used in this text to refer to the following groups of individuals: actuaries (person who computes insurance risk and premium rates based on statistical data), academic researchers, community representatives, ethics committees, genetic counsellors, genomic researchers, human rights experts, insurers, governmental representatives, non-governmental organisations, patient representatives, physicians, policy makers, popular media, reinsurers (company in charge of calculating the risk and premium amount for insuring a particular customer), research participants, and underwriters (company or person in charge of calculating the risk involved in providing insurance for a particular customer and to decide how much should be paid for the premium). This list is not meant to be exhaustive as relevant new groups may emerge as this topic further develops in the coming years. A multidisciplinary group of international experts representing different interests (hereinafter ‘the Expert Group'') revisited the genetics and life insurance debate. The following text presents a summary of the issues discussed and the ‘Action Items'' agreed upon by the Expert Group at the ‘Life Insurance, Risk Stratification, and Personalized Medicine Symposium''.  相似文献   
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5F‐PY‐PICA and 5F‐PY‐PINACA are pyrrolidinyl 1‐(5‐fluoropentyl)ind (az)ole‐3‐carboxamides identified in 2015 as putative synthetic cannabinoid receptor agonist (SCRA) new psychoactive substances (NPS). 5F‐PY‐PICA, 5F‐PY‐PINACA, and analogs featuring variation of the 1‐alkyl substituent or contraction, expansion, or scission of the pyrrolidine ring were synthesized and characterized by nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography–quadrupole time‐of‐flight–mass spectrometry (LC–QTOF–MS). In competitive binding experiments against HEK293 cells expressing human cannabinoid receptor type 1 (hCB1) or type 2 (hCB2), all analogs showed minimal affinity for CB1 (pKi < 5), although several demonstrated moderate CB2 binding (pKi 5.45–6.99). In fluorescence‐based membrane potential assays using AtT20‐hCB1 or ‐hCB2 cells, none of the compounds (at 10 μM) produced an effect >50% of the classical cannabinoid agonist CP55,940 (at 1 μM) at hCB1, although several showed slightly higher relative efficacy at hCB2. Expansion of the pyrrolidine ring of 5F‐PY‐PICA to an azepane ( 8 ) conferred the greatest hCB2 affinity (pKi 6.99) and activity (pEC50 7.54, Emax 72%) within the series. Unlike other SCRA NPS evaluated in vivo using radio biotelemetry, 5F‐PY‐PICA and 5F‐PY‐PINACA did not produce cannabimimetic effects (hypothermia, bradycardia) in mice at doses up to 10 mg/kg.  相似文献   
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