Unlabelled: Sufficient vasodilatory and vasoconstrictive reactivity of cerebral arterioles is an important prerequisite for adequate capillary perfusion. To appreciate its capacity during aging and to elucidate its impact on parenchymal integrity we undertook a correlation using ultrasonography and brain MRI. Sixty healthy persons with no stenoses in the carotid and vertebral arteries were examined by transcranial Doppler to assess middle cerebral artery mean flow velocities (MFV) at rest, after 30 s apnea and after 90 s hyperventilation. Young persons, N=20, with a mean age of 24.8 (20-32) were compared with the middle aged, N=20, 54.8 (40-63) and elderly, N=20, 76.2 (69-84). A different cohort of 40 elderly persons, with a mean age of 68.4 (57-85) were evaluated also by MRI using FLAIR and T2-weighted sequences. Their extent of leukoaraiosis measured by the Fazekas scale was correlated with their vasoregulatory capacity.
Results: The steady state MFV in young persons, 71 cm/sec, decreases to 48.1 and to 44.9 cm/sec in the middle and the old aged. The post-apnoic vasodilatation in young persons accelerates the MCA blood velocity by 41.7%, while in middle and old age only by 37.6 and 32.9% respectively. The MCA deceleration post-hyperventilation by 50.2% in young people decreases to 39.1% and to 29.7% respectively in the older categories. The correlation of periventricular hyperintensities and deep white matter lesions was found highest with the index of resistance (0.45, p<0.05) while with the apnoic acceleration and hyperventilatory deceleration it was minimal (0.01 and 0.08 respectively).
Conclusion: The extent of vasoregulatory capacity during aging decreases along with the decreasing basic MFV. Its effect on the initial stages of leukoaraiosis is minimal.
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http://dx.doi.org/10.1016/j.jns.2010.08.064 | DOI Listing |
Arch Immunol Ther Exp (Warsz)
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Department of Human Physiology, Medical University of Lublin, Lublin, Poland.
Systemic lupus erythematosus (SLE) is an autoimmune disease whose pathogenesis is not fully understood to date. One of the suggested mechanisms for its development is NETosis, which involves the release of a specific network consisting of chromatin, proteins, and enzymes from neutrophils, stimulating the immune system. One of its markers is citrullinated histone H3 (H3Cit).
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January 2025
Sungkyunkwan University, Seoul, Republic of Korea.
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J Med Internet Res
January 2025
College of Public Health, The Ohio State University, Columbus, OH, United States.
Background: Young gay, bisexual, and other men who have sex with men have been referred to as a "hard-to-reach" or "hidden" community in terms of recruiting for research studies. With widespread internet use among this group and young adults in general, web-based avenues represent an important approach for reaching and recruiting members of this community. However, little is known about how participants recruited from various web-based sources may differ from one another.
View Article and Find Full Text PDFJ Forensic Odontostomatol
December 2024
Laboratory of Personal Identification and Forensic Morphology, Department of Health Sciences, University of Florence, Florence, Italy.
The age estimation of skeletal remains still represents a central issue not only for the reconstruction of the so-called "biological profile," but mostly for the palaeodemographic investigation. This research aims at verifying the feasibility of the adult age estimation method developed on living people by Pinchi et al. (2015 and 2018), for estimating the age at the death of 37 subjects from ancient populations found in two different Italian necropolis of archaeological interest (Mont'e Prama and Florence, X-IX century B.
View Article and Find Full Text PDFJ Forensic Odontostomatol
December 2024
Faculty of Dentistry, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
This study aims to compare the accuracy of Demirjian's and Cameriere's methods in determining adult age at the 18-year threshold using mandibular third molars in the Thai population. Panoramic radiograph images of 504 healthy subjects aged between 14 and 23 years were retrospectively collected. The developmental stages of mandibular third molars were evaluated using Demirjian's method, while the maturity index of mandibular third molars (I3M) was assessed using Cameriere's method.
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