Cytosolic free calcium levels increase with age in rat brain synaptosomes

Calcium homeostasis in synaptosomes is altered during ageing. The cytosolic free calcium concentration, [Ca2+]i was determined in synaptosomes and crude synaptosomal fractions from 3- and 24-month-old rats with the fluorescent indicator quin-2. The [Ca2+]i were around two times higher in 24-month-old rats than in adults, both under resting conditions and after K depolarization. This difference was still observed after incubation with an endogenous heavy metal chelator. To avoid the calcium buffering effect of quin-2, [Ca2+]i values were determined with the use of a null-point method and with fura-2. These methods confirmed the increase in [Ca2+]i with age in synaptosomes. The increase in [Ca2+]i in nerve endings may be pathologically important in brain ageing.     

Antiretroviral treatment in resource-poor settings: the Brazilian experience

The Brazilian HIV/AIDS drug policy has been highly debated and even criticized, particularly at the time of its implementation by the Government in early 90s. However, after more than a decade of action, the success of the Brazilian response to HIV is evident and recognized worldwide, lying upon a concerted early governmental response, a strong and effective participation of the civil society, a multisectoral mobilization, a balanced prevention and treatment approach and the advocacy of human rights in all strategies, particularly with the policy of wide access to antiretroviral drugs. This policy made highly active anti-retroviral therapy (HAART) universally available since 1996, with logistic and criteria distribution based on regularly updated national guidelines. Approximately 140,000 patients now receive antiretroviral (ARV) treatment through the public health system. As a result there has been a significant fall in morbidity/mortality rates, hospital admissions and costs of treatment, with significant growth in demand for outpatient services and decrease for hospital, home and day-care services. It has also led to improvements in the quality of life for HIV+ individuals and savings in the medical costs, while economic and social related costs also have fallen. The policy of universal access to combined antiretroviral treatment (ART)' in Brazil has been shown to be cost-effective and the financial resources devoted to this initiative represents an economically viable investment. This experience also shows that a well-designed and supported international effort to reduce drug prices and improve health infrastructure could overcome many obstacles in middle-income and limited-resource countries.     

Basic principles and equipment in neuroendoscopy

In sum, understanding some of the basic principles of endoscopy and awareness of available resources can potentially be of considerable help to experienced neurosurgeons as well as beginners in selection of the most appropriate tools for different procedures and making cost-effective choices when browsing through multiple commercial advertisements and purchasing new equipment. Although numerous advantages in science and industry have made it possible to offer a wide variety of neuroendoscopes and tools, we believe the major achievements in this field are yet to occur. This particularly refers to the development of smaller fiberoptic scopes with better image quality and three-dimensional endoscopes and to the invention of more efficient tools for endoscopic tumor removal with the same degree of safety as in open surgery.     

Systolic BP and Mortality in Older Adults with CKD

Background and objectives

Optimal BP targets for older adults with CKD are unclear. This study sought to determine whether a nonlinear relationship between BP and mortality—as described for the broader CKD population and for older adults in the general population—is present for older adults with CKD.

Design, setting, participants, & measurements

A cohort of 21,015 adults age 65–105 years with a moderate or severe reduction in eGFR (<60 ml/min per 1.73 m²) were identified within the Kaiser Permanente Northwest Health Maintenance Organization population. The relationship between baseline systolic BP (SBP; ≤120, 121–130, 131–140, 141–150, >150 mmHg; referent, 131–140 mmHg) and all-cause mortality across age groups (65–70, 71–80, and >80 years) was examined; patients were followed for up to 11 years after cohort entry.

Results

The median times at risk were 3.15 years, 3.53 years, and 2.76 years for adults age 65–70, 71–80, and >80 years, respectively. Mortality during follow-up was 19.6% for those age 65–70 years, 33.4% for those age 71–80 years, and 55.7% for those age >80 years. The relationship between SBP and mortality varied as a function of age. The risk of death was highest for patients with the lowest SBP in all age groups. Only among adults age 65–70 years was an SBP>140 mmHg associated with a higher risk of death compared with the referent category. Patterns of age modification of the relationship between SBP and mortality were consistent in all sensitivity analyses.

Conclusions

In a cohort of older adults, the relationship between SBP and mortality varied systematically with age. A relationship between higher SBP and mortality was present only for younger members of this cohort and not for those older than 70. These results raise the question of whether the relative benefits and harms of lowering BP to recommended targets for older adults with CKD may vary as a function of age.