The majority of the brain’s vasculature is comprised of intricate capillary networks lined by capillary pericytes. However, it remains unclear whether capillary pericytes influence blood flow. Using two-photon microscopy to observe and manipulate brain capillary pericytes in vivo , we find that their optogenetic stimulation decreases lumen diameter and blood flow, but with slower kinetics than similar stimulation of mural cells on upstream pial and pre-capillary arterioles. This slow vasoconstriction was inhibited by the clinically-used vasodilator fasudil, a Rho-kinase inhibitor that blocks contractile machinery. Capillary pericytes were also slower to constrict back to baseline following hypercapnia-induced dilation, and slower to dilate towards baseline following optogenetically-induced vasoconstriction. Optical ablation of single capillary pericytes led to sustained local dilation and a doubling of blood cell flux selectively in capillaries lacking pericyte contact. These data indicate that capillary pericytes contribute to basal blood flow resistance and slow modulation of blood flow throughout the brain.

The majority of the brain’s vasculature is comprised of intricate capillary networks lined by capillary pericytes. However, it remains unclear whether capillary pericytes contribute to blood flow control. Using two-photon microscopy to observe and manipulate single capillary pericytes in vivo, we find their optogenetic stimulation decreases lumen diameter and blood flow, but with slower kinetics than mural cells of upstream pial and pre-capillary arterioles. This slow, optogenetically-induced vasoconstriction was inhibited by the clinically-used vasodilator fasudil, a Rho kinase inhibitor that blocks contractile machinery. Capillary pericytes were also slower to constrict back to baseline following hypercapnia-induced dilation, and relax towards baseline following optogenetically-induced vasoconstriction. In a complementary approach, optical ablation of single capillary pericytes led to sustained local dilation and a doubling of blood cell flux in capillaries lacking pericyte contact. Altogether these data indicate that capillary pericytes contribute to basal blood flow resistance and slow modulation of blood flow throughout the capillary bed.

This study shows that in the Italian population aged >or=45, hospitalizations following hip fracture and AMI between 1999 and 2002 were comparable, while hip fractures' direct costs were higher and grew faster than costs for AMI. Hip fractures in Italy are a serious medical problem and a leading health-cost driver.

Background Facioscapulohumeral muscular dystrophy (FSHD) is a patchy and slowly progressive disease of skeletal muscle. For MRI to be a useful biomarker in an FSHD clinical trial, it should reliably detect changes over relatively short time-intervals (~ 1 year). We hypothesized that fatty change over the study course would be most likely in muscles already demonstrating disease progression, and that the degree of MRI burden would be correlated with function. Methods We studied 36 patients with FSHD and lower-extremity weakness at baseline. Thirty-two patients returned in our 12-month longitudinal observational study. We analyzed DIXON MRI images of 16 lower-extremity muscles in each patient and compared them to quantitative strength measurement and ambulatory functional outcome measures. Results There was a small shift to higher fat fractions in the summed muscle data for each patient, however individual muscles demonstrated much larger magnitudes of change. The greatest increase in fat fraction was observed in muscles having an intermediate fat replacement at baseline, with minimally (baseline fat fraction < 0.10) or severely (> 0.70) affected muscles less likely to progress. Functional outcome measures did not demonstrate marked change over the interval; however, overall MRI disease burden was correlated with functional outcome measures. Direct comparison of the tibialis anterior (TA) fat fraction and quantitative strength measurement showed a sigmoidal relationship, with steepest drop being when the muscle gets more than ~ 20% fatty replaced. Conclusions Assessing MRI changes in 16 lower-extremity muscles across 1 year demonstrated that those muscles having an intermediate baseline fat fraction were more likely to progress. Ambulatory functional outcome measures are generally related to overall muscle MRI burden but remain unchanged in the short term. Quantitative strength measurement of the TA showed a steep loss of strength when more fatty infiltration is present suggesting that MRI may be preferable for following incremental change or modulation with drug therapy.

Background Families with food allergy (FA) are at risk of reduced quality of life and elevated anxiety. A moderate level of anxiety may be beneficial to sustain vigilance for food avoidance; however, excessive anxiety may increase risk for burden and maladjustment. The current study presents a framework for understanding patterns of adaptation to FA across families and to identify typologies of families that would benefit from intervention. Methods Participants included 57 children, 6 to 12 years old with documented FA, and their mothers. Families were assessed using the Food Allergy Management and Adaptation Scale. Families also completed measures of quality of life, anxiety, FA management, and psychosocial impairment. Results A hierarchical cluster analysis revealed that 56 of the 57 families of food allergic children were categorized into four groups that differed on their adequacy of family FA management, levels of anxiety, and balanced psychosocial functioning: Balanced Responders (n = 23; 41%), High Responders (n = 25; 45%), and Low Responders (n = 3; 5%). The fourth group, Anxious High Responders (n = 5; 9%), was characterized by extremely high maternal FA anxiety scores and low scores for balanced integration of FA management and psychosocial functioning. Families in clusters differed across illness and psychosocial outcome variables. Conclusion Families with FA were characterized by patterns of FA management, anxiety, and ability to integrate FA demands into daily life. Identified adaptation patterns correspond with clinical impressions and provide a framework for identifying families in need of intervention.