scholarly journals The bioelectric type of the visual area of the cerebral cortex of rats of all ages and sexes

2018 ◽  
Vol 9 (4) ◽  
pp. 514-521
Author(s):  
V. V. Mizin ◽  
V. P. Lyashenko ◽  
S. M. Lukashov
Keyword(s):  
Cerebral Cortex ◽  
Theta Rhythm ◽  
Age Groups ◽  
Young Age ◽  
Visual Area ◽  
Age Group ◽  
Bioelectric Activity ◽  
Absolute Power ◽  
Age Related ◽  
Age Related Changes

In the ontogenesis process, the cerebral cortex undergoes age-related changes. So far as, unlike practically all other systems of mammalian organs, the brain continues to develop and receive new functionality in the postnatal period. Thus with age, there are changes in the bioelectric characteristics of the neocortex. The purpose of the research is to determine the age and sex changes in the bioelectric activity of the cerebral visual cortex of male and female rats of different ages. In the article, we examined changes in absolute (μV2) and normalized (%) indicators of electrical activity of the visual area of rats of different sexes in four age groups: juvenile, young, mature, and presenile age. The research was carried out by the method of registration of bioelectric activity of electrocorticograms (ECoG). Results of multifactorial dispersion analysis of absolute and normalized ECoG indicators of the visual area of the cerebral cortex of rats of all ages showed that there were reliable changes in the frequency-amplitude characteristics of bioelectric activity related to age. At a young age, males have probably lower absolute and normalized power of the delta-rhythm and the normalized beta-like rhythm rate. There was a tendency of decrease in the theta-rhythm. As a result of this redistribution of rhythms a desynchronization of the electrical activity of young males was observed. Mature males have lower absolute power indicators than younger age groups. According to normalized indicators, a synchronization of rhythms of males in the mature age group was observed, which together with values of absolute power can indicate a decrease of the functional activity level of the neocortex and an increase of the influence of endogenous mechanisms on neuronal activity of the visual area of the cerebral cortex. In the presenile age, there was a desynchronization of rhythms. The indicators of an absolute and normalized power of females in the young age group pointed to the synchronization of the bioecoactivity of the neocortex. Among the low-frequency waves, theta-rhythm rhythm dominated in the females of young age. In the mature and presenile age females, there was a probable increase in the percentage of normalized parameters of high-frequency beta waves. The predominance of this rhythm may indicate an increase of cortical tone. The correlation of values of absolute and normalized indicators of bioelectric activity affirmed the desynchronization of the ECoG rhythms of females of mature and presenile age. Sex differences are expressed by a decrease in the absolute power of all ECoG rhythms of the visual area of the cerebral cortex of females relative to males. The age-related changes occurred in a different way in rats of different sex. At a young age, males had desynchronization of rhythms, and females had synchronization, in the mature age it was vice versa. The age changes of the electric activity of the cerebral visual cortex of rats in our opinion may be largely associated with involutional changes of various neurotransmitter and hormonal systems.

scholarly journals Conductive Hearing Loss with Age—A Histologic and Audiometric Evaluation

2021 ◽  
Vol 10 (11) ◽  
pp. 2341
Author(s):  
Ivo Dobrev ◽  
Daniel Dillinger ◽  
Letizia Meier ◽  
Dorothe Veraguth ◽  
Flurin Pfiffner ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Conductive Hearing Loss ◽  
Age Groups ◽  
Joint Space ◽  
Age Group ◽  
Interindividual Variations ◽  
Age Related ◽  
Average Change ◽  
Conductive Hearing ◽  
Age Related Changes

A retrospective analysis to quantify age-related changes of the incudo-malleolar joint (IMJ) and incudo-stapedial joint (ISJ), and to analyse changes in the air-bone gap (ABG) with age, was performed. Defined histologic parameters of 153 IMJ and 106 ISJ from subjects aged from birth to 70 years were correlated to age. Additionally, audiograms of 1760 ears of 974 other subjects aged 20 to 80 years were retrospectively analysed and the ABG was correlated to age. The joint space (age group from 0 to 10 compared to 61 to 70 years) became significantly wider with age (IMJ: from a mean of 44 µm to 100 µm, p < 0.001; ISJ: from a mean of 28 µm to 69 µm, p < 0.009. The thickness of cartilage of the incus decreased in the first 20 years of life (IMJ, from a mean of 88 µm to 65 µm, p < 0.01; ISJ: from a mean of 44 µm to 35 µm, p < 0.01). The ABGs of younger ears (20–40 years) was significantly larger at 500 Hz compared to older ears (60–80 years) by 2–4 dB, while it was significantly smaller by 3–5 dB at 4000 Hz (p < 0.0017). Interindividual variations in all age groups were large for both analyses. The increased joint spaces could potentially reduce the stiffness in the joints and explain the increase in ABG at 4000 Hz and the drop at 500 Hz. While the average change is small and of minimal clinical relevance, a larger increase of ABG with age is seen in some subjects.

Benchmarking Typically Developing Children’s Prosodic Performance on the Irish-English Version of the Profiling Elements of Prosody in Speech-Communication (PEPS-C)

2011 ◽  
Vol 18 (1) ◽  
pp. 19-40
Author(s):  
Michelle Foley ◽  
Fiona E. Gibbon ◽  
Susan Peppé
Keyword(s):  
Old Age ◽  
Age Groups ◽  
Chance Level ◽  
Speech Communication ◽  
Age Group ◽  
Typically Developing ◽  
English Version ◽  
Typically Developing Children ◽  
Age Related ◽  
Age Related Changes

Objective: To develop the Irish-English version of the Profiling Elements of Prosody in Speech-Communication (PEPS-C) assessment, identify the normal prosodic performance of typically developing children aged 5–11 years on the PEPS-C assessment, and identify significant age-related changes between different age groups. Method: Thirty typically developing children between the ages of 5;9 and 11;1 years completed the PEPS-C assessment, which involved both receptive and expressive tasks. Results: Significant differences were found between the youngest group’s prosodic performance and the two older groups. The 5- to 6-year-old age group performed less well than the 10- to 11-year-old age group (p < 0.05). The 10- to 11-year-old age group performed above chance level on all prosodic tasks. Conclusion: While 5- and 6-year-old children have acquired some functional prosodic skills, there are further developments between the ages of 5;9 and 9;5, with some aspects of prosody continuing to develop up to 11 years.

scholarly journals Age-Related Changes of the Pineal Gland in Humans: A Digital Anatomo-Histological Morphometric Study on Autopsy Cases with Comparison to Predigital-Era Studies

Medicina ◽  
2021 ◽  
Vol 57 (4) ◽  
pp. 383
Author(s):  
Bogdan-Alexandru Gheban ◽  
Horațiu Alexandru Colosi ◽  
Ioana-Andreea Gheban-Rosca ◽  
Bogdan Pop ◽  
Ana-Maria Teodora Domșa ◽  
...  
Keyword(s):  
Pineal Gland ◽  
Age Groups ◽  
Polarized Light ◽  
Morphometric Study ◽  
Age Group ◽  
Autopsy Study ◽  
Pediatric Age Group ◽  
Age Related ◽  
The Brain ◽  
Age Related Changes

Background and objectives: The pineal gland is a photoneuroendocrine organ in the midline of the brain, responsible primarily for melatonin synthesis. It is composed mainly of pinealocytes and glial tissue. This study examined human postmortem pineal glands to microscopically assess age-related changes using digital techniques, and offers a perspective on evolutionary tendencies compared to the past. Materials and Methods: A retrospective autopsy study has been performed on 72 pediatric and adult autopsy cases. The glands have been processed for histological analysis and immunohistochemical staining with glial fibrillary acidic protein (GFAP). Slides were assessed under polarized light and digitally scanned. Morphometric data were obtained using CaseViewer and ImageJ. Results: Thirty-three females and 39 males were included in the study, grouped under three age groups: 0–25, 46–65, and 66–96 years of age. The peak gland volume was found within the 46–65 age group, the overall mean volume was 519 mm3, the main architectural types were lobular and insular, and the mean percentage of pineal calcification was 15% of the gland, peaking within the 66–96 age group, with a predominantly globular shape. Glial cysts were found in 20.8% of cases. The intensity of GFAP stain was maximal in the pediatric age group, but the extent of glial tissue was much larger in elderly patients. Discussion: The degenerative process of the pineal gland can be quantified by measuring normal parenchyma, calcifications, glial tissue, and glial cysts. Morphometric differences have been observed and compared to a similar studies performed in the published literature. The current study, unfortunately, lacks a 26–45 age group. Digital techniques seemed to offer a more exact analysis, but returned similar results to studies performed over 40 years ago, therefore offering important information on evolutionary tendencies. Conclusions: Increase in glial tissue, calcifications, and glial cysts have a defining role as age-related changes in the pineal gland.

scholarly journals Age related changes in the primary somatosensory area of the cerebral cortex

2020 ◽  
Vol 11 (5) ◽  
pp. 87-92
Author(s):  
Santos George Joseph ◽  
Anne George
Keyword(s):  
Cerebral Cortex ◽  
Structural Integrity ◽  
Age Groups ◽  
Pyramidal Cells ◽  
Stellate Cells ◽  
Somatosensory Area ◽  
Age Related ◽  
Study Results ◽  
The Impact ◽  
Age Related Changes

Background: Age-related changes in structural and functional part of brain have been the motivation of previous and ongoing neuroscientific research. The focus of most studies done, were on different motor areas of the of the cerebral cortex. Very few studies were done on primary somatosensory areas of the brain. Aims and Objective: The aim of the study was to investigate the age-related changes in primary somatosensory area of the cerebral cortex of the human brain. Materials and Methods: The study was conducted on 50 autopsied brain specimens. The specimens removed were of both sexes belonging to various age groups ranging from 9 months to 75 years. The specimens were collected from the Department of Forensic Medicine, Medical College Kottayam. During the autopsy the meninges were carefully stripped off. The sulci and gyri were then examined carefully. Results: The depth of the upper area of the central sulcus is more than the middle and lower areas, both in the right and left halves of the cerebral cortex. The laminae of the primary somatosensory area have shown that as age advances there is a progressive increase in thickness except in the case of lamina IV. From the ages of 61 years onwards, laminar degeneration takes place. The thickest lamina was lamina V. The thinnest laminawas lamina IV. The stellate cells that dominate in lamina II and IV show a difference in their arrangement. In foetal life, the pyramidal cells were almost indistinguishable from the stellate cells. The pyramidal cells were seen mostly in lamina III and V. Conclusion: The study results suggest the possibility that in the more advanced stages of aging, the structural integrity of lamina IV is more consistent than other layers present in primary somatosensory area of the cerebral cortex. Further study is needed to examine the impact of ageing on somatosensory area.

scholarly journals Age-Related Changes in the Microvascular Density of the Human Meniscus

2021 ◽  
pp. 036354652110398
Author(s):  
Philipp A. Michel ◽  
Christoph J. Domnick ◽  
Michael J. Raschke ◽  
Anna Hoffmann ◽  
Christoph Kittl ◽  
...  
Keyword(s):  
Linear Trend ◽  
Smooth Muscle Actin ◽  
Statistical Significance ◽  
Tumor Resection ◽  
Age Groups ◽  
Vascular Density ◽  
Age Group ◽  
Human Knee ◽  
Age Related ◽  
Age Related Changes

Background: The microvascular anatomy of the meniscus of the human knee is regarded as a crucial factor in the injury response. Previous studies have investigated the zone-dependent distribution pattern, but no quantitative data exist on vascular density and its age-related changes. Hypothesis/Purpose: The aim of the present study was to histologically analyze the vascular anatomy of the meniscus as a function of age. It was hypothesized that vascular density would decrease with increasing age. Study Design: Descriptive laboratory study. Methods: Human menisci were retrieved from patients who underwent tumor resection or who received total knee replacement because of osteoarthritis. A total of 51 menisci were collected from 28 patients over 9 years (mean age, 25.6 ± 20.4 years; range 3-79 years). Immunohistological staining (alpha–smooth muscle actin) in combination with serial sections and standardized software-based contrast detection were used for the quantitative analysis. Data were analyzed using multiple t tests and the analysis of variance for trends, with a statistical significance level of P < .05. Results: The overall vascular density in the meniscus was lower in the 61- to 80-year age group than in the age groups of 0 to 10, 11 to 20, and 21 to 30 years ( P < .01). A negative linear trend was detected with increasing age (slope, -0.007; P = .016). Within the red-white (RW) zone, a low vessel density was detected for the age groups of 0 to 10 and 11 to 20 years. Beyond these age groups, no vasculature was found in the RW zone. For the white-white (WW) zone, no vessel formations were noted in any age group. Almost 95% of the vessels in the meniscus were located in the capsule. Conclusion: This study reports quantitative histological data for microvascular anatomy as a function of age in a broad cohort of human knee menisci. The overall vascular density decreased with increasing age. No vessel formations were detected in the RW and WW zones after adolescence. Additionally, the capsule is far more densely vascularized than any other part of the meniscus. Clinical Relevance: Vascular density might be an additional factor to consider, along with tear location and patient age, for future treatment options.

scholarly journals Influence of Patient Age on Streptococcus pneumoniae Serotypes Causing Invasive Disease

2001 ◽  
Vol 8 (3) ◽  
pp. 556-559 ◽  
Author(s):  
Jaime Inostroza ◽  
Ana Maria Vinet ◽  
Gloria Retamal ◽  
Pedro Lorca ◽  
Gonzalo Ossa ◽  
...  
Keyword(s):  
Age Groups ◽  
Invasive Disease ◽  
Bacterial Virulence ◽  
Host Factors ◽  
Invasive Infection ◽  
Age Group ◽  
Southern Chile ◽  
Age Related ◽  
Sterile Site ◽  
Selection Of

ABSTRACT All clinical S. pneumoniae specimens isolated from patients with invasive or sterile-site infections admitted to one regional general hospital in southern Chile were collected during a 5-year period (February 1994 to September 1999). A total of 247 strains belonging to 50 serotypes were isolated in this survey: 69 in patients under 5 years of age, 129 in patients 5 to 64 years old, and 49 from patients 65 years and older. Eight serotypes were identified in all age groups, while all other serotypes were found exclusively in one age group or in patients over 4 years of age. Serotype 3 was never found in patients under 5 years old, and serotype 14 was not found in patients >64 years of age. There was no difference in the serotypes causing infection in each one of the 5 years of the survey. Our results suggest that both bacterial virulence factors and host factors play an important role in the selection of S. pneumoniae serotypes causing invasive infection. Possible host factors include age-related differences in the immune response. Comparative studies with other areas of the world may help to further understanding of our observations in southern Chile.

Age Related Prevalence of Pre-Eruptive Intracoronal Radiolucent Defects in the Permanent Dentition

2016 ◽  
Vol 40 (2) ◽  
pp. 103-106 ◽  
Author(s):  
Marina Umansky ◽  
Nili Tickotsky ◽  
Silvina Friedlander-Barenboim ◽  
Sarit Faibis ◽  
Moti Moskovitz
Keyword(s):  
Retrospective Study ◽  
Age Groups ◽  
Third Molar ◽  
Young Group ◽  
Young Age ◽  
Permanent Teeth ◽  
Significance Level ◽  
Adult Age ◽  
Age Related ◽  
Unerupted Teeth

Objective: The present study aimed to determine if the prevalence of pre-eruptive intracoronal radiolucent defects is higher for young age groups, in which there are more unerupted teeth. Study design: A retrospective study of panoramic and bitewing radiographs was conducted. An inclusion criterion was the presence of un-erupted permanent teeth with a formed and clearly visible crown. Age groups were: young (6–8 years), intermediate (9–12 years) and adults (13–53 years). Significance level was set at p≤0.05. Results: Thirteen (3.9%) pre-eruptive lesions were detected in 335 records. No lesions were found in the young group (7.4%), in the intermediate and adult age groups six and seven lesions were found, respectively. In most cases the pre-eruptive lesion was found in a third molar. Conclusion: The prevalence of pre-eruptive intracoronal lesions was not higher for young age groups. The prevalence of pre-eruptive intra coronal radiolucent lesions is 3.9%, irrespective of age.

Multiple Saccades Are More Automatic Than Single Saccades

2007 ◽  
Vol 97 (4) ◽  
pp. 3148-3151 ◽  
Author(s):  
Paul van Donkelaar ◽  
Sandy Saavedra ◽  
Marjorie Woollacott
Keyword(s):  
Cerebral Cortex ◽  
Age Groups ◽  
Age Group ◽  
Control Task ◽  
Initial Saccade ◽  
Fixation Control

In this paper, we demonstrate that when a peripheral object is foveated by a sequence of multiple saccades, the initial saccade in the sequence is initiated markedly faster than a single accurate saccade to the same object. We suggest that multiple saccades represent a more automatic form of oculomotor planning that may be the result of a reduced influence from the cerebral cortex. To test this, we compared single and multiple saccade characteristics across development. We find that in contrast to the reduction in the latency of single saccades that is observed across development, the latency of initial saccades in multiple saccade sequences is remarkably stable across all age groups. Moreover, the longer the latency of this initial saccade, the more accurate it is, suggesting that there is a relation between the degree of procrastination and the accuracy of the response. Finally, the frequency with which multiple saccades occurred within each age group was positively correlated with the tendency to generate erroneous saccades during a fixation control task. Taken together, the present data suggest that multiple saccades are generated in a more automatic manner than single saccades.

Age and outcome after aneurysmal subarachnoid hemorrhage: why do older patients fare worse?

1996 ◽  
Vol 85 (3) ◽  
pp. 410-418 ◽  
Author(s):  
Giuseppe Lanzino ◽  
Neal F. Kassell ◽  
Teresa P. Germanson ◽  
Gail L. Kongable ◽  
Laura L. Truskowski ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Subarachnoid Hemorrhage ◽  
Age Groups ◽  
Age Group ◽  
Content Type ◽  
Poor Outcome ◽  
Symptomatic Vasospasm ◽  
Age Related ◽  
Increased Risk ◽  
Fine Print

✓ Advanced age is a recognized prognostic indicator of poor outcome after subarachnoid hemorrhage (SAH). The relationship of age to other prognostic factors and outcome was evaluated using data from the multicenter randomized trial of nicardipine in SAH conducted in 21 neurosurgical centers in North America. Among the 906 patients who were studied, five different age groups were considered: 40 years or less, 41 to 50, 51 to 60, 61 to 70, and more than 71 years. Twenty-three percent of the individuals enrolled were older than 60 years of age. Women outnumbered men in all age groups. Level of consciousness (p = 0.0002) and World Federation of Neurological Surgeons grade (p = 0.0001) at admission worsened with advancing age. Age was also related to the presence of a thick subarachnoid clot (p = 0.0001), intraventricular hemorrhage (p = 0.0003), and hydrocephalus (p = 0.0001) on an admission computerized tomography scan. The rebleeding rate increased from 4.5% in the youngest age group to 16.4% in patients more than 70 years of age (p = 0.002). As expected, preexisting medical conditions, such as diabetes (p = 0.028), hypertension (p = 0.0001), and pulmonary (p = 0.0084), myocardial (p = 0.0001), and cerebrovascular diseases (p = 0.0001), were positively associated with age. There were no age-related differences in the day of admission following SAH, timing of the surgery and/or location, and size (small vs. large) of the ruptured aneurysm. During the treatment period, the incidence of severe complications (that is, those complications considered life threatening by the reporting investigator) increased with advancing age, occurring in 28%, 33%, 36%, 40%, and 46% of the patients in each advancing age group, respectively (p = 0.0002). No differences were observed in the reported frequency of surgical complications. No age-related differences were found in the overall incidence of angiographic vasospasm; however, symptomatic vasospasm was more frequently reported in the older age groups (p = 0.01). Overall outcome, assessed using the Glasgow Outcome Scale at 3 months post-SAH, was poorer with advancing age (p < 0.001). Multivariate analysis of overall outcome, adjusting for the different prognostic factors, did not remove the age effect, which suggests that the aging brain has a less optimal response to the initial bleeding. Age as a risk factor is a continuum; however, there seems to be a significant increased risk of poor outcome after the age of 60 years.

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