Functional maturation of tactile sensory fibers in the kitten

1984 ◽  
Vol 52 (1) ◽  
pp. 74-85 ◽  
Author(s):  
D. G. Ferrington ◽  
M. O. Hora ◽  
M. J. Rowe
Keyword(s):  
Age Groups ◽  
Postnatal Period ◽  
High Frequencies ◽  
Functional Changes ◽  
Functional Maturation ◽  
Tactile Stimuli ◽  
Adult Cats ◽  
Skin Indentation ◽  
Sensory Fibers ◽  
Cutaneous Vibration

The maturation of tactile coding capacities was investigated in sensory fibers supplying the forelimb footpads in anesthetized kittens. Fibers were isolated by microdissection from the median or ulnar nerves of neonatal kittens (1st to 5th postnatal day) and kittens in the age categories 10-15, 25-30, 55-63, and 83-90 days. The use of quantitative, reproducible tactile stimuli, in particular, cutaneous vibration, and objective analytical procedures enabled response parameters to be quantified and compared at different ages with those of adult fibers. While three classes of myelinated tactile sensory fibers are associated with the footpads in adult cats, one of them slowly adapting (SA) and two, the rapidly adapting (RA) and pacinian corpuscle (PC) classes, showing pure dynamic sensitivity, this breakdown into three classes is not apparent until 10-15 days after birth. In all age groups, the SA fibers displayed responses that were graded depending on the magnitude of the skin indentation. However, in younger kittens (less than 25-30 days) plateau levels of response were sometimes attained over a narrow range (0.5 mm) of indentation. From 10-15 days, when RA fibers are identifiable, their sensitivity, as measured by absolute and 1:1 thresholds to cutaneous vibration, was independent of age at low vibration frequencies, less than or equal to 80 Hz. However, at high frequencies, e.g., 200 Hz, their thresholds appeared to decrease during the 1st postnatal month with a resulting expansion in their bandwidth of vibratory sensitivity. At their best frequency, around 30 Hz, RA fibers appear mature by 10-15 days in their capacity for encoding vibratory frequency information. The PC class of tactile afferents displayed the most striking functional changes with age. Their vibratory bandwidths, at 50-micron amplitude, expand from an upper limit of about 200-300 Hz in the neonate to mature values of about 800-1,000 Hz over a 2-mo postnatal period.(ABSTRACT TRUNCATED AT 400 WORDS)

The potential role of stress and sex steroids in heritable effects of sevoflurane

2021 ◽  
Author(s):  
Anatoly E Martynyuk ◽  
Ling-Sha Ju ◽  
Timothy E Morey
Keyword(s):  
Sex Steroids ◽  
Age Groups ◽  
Postnatal Period ◽  
Health Concern ◽  
General Anesthetics ◽  
Pharmacological Agents ◽  
Experimental Findings ◽  
Heritable Effects

Abstract Most surgical procedures require general anesthesia, which is a reversible deep sedation state lacking all perception. The induction of this state is possible because of complex molecular and neuronal network actions of general anesthetics (GAs) and other pharmacological agents. Laboratory and clinical studies indicate that the effects of GAs may not be completely reversible upon anesthesia withdrawal. The long-term neurocognitive effects of GAs, especially when administered at the extremes of ages, are an increasingly recognized health concern and the subject of extensive laboratory and clinical research. Initial studies in rodents suggest that the adverse effects of GAs, whose actions involve enhancement of GABA type A receptor activity (GABAergic GAs), can also extend to future unexposed offspring. Importantly, experimental findings show that GABAergic GAs may induce heritable effects when administered from the early postnatal period to at least young adulthood, covering nearly all age groups that may have children after exposure to anesthesia. More studies are needed to understand when and how the clinical use of GAs in a large and growing population of patients can result in lower resilience to diseases in the even larger population of their unexposed offspring. This minireview is focused on the authors’ published results and data in the literature supporting the notion that GABAergic GAs, in particular sevoflurane, may upregulate systemic levels of stress and sex steroids and alter expressions of genes that are essential for the functioning of these steroid systems. The authors hypothesize that stress and sex steroids are involved in the mediation of sex-specific heritable effects of sevoflurane.

The effects of Fasciola hepatica on Lymnaea truncatula

Parasitology ◽  
1972 ◽  
Vol 65 (2) ◽  
pp. 359-369 ◽  
Author(s):  
J. K. M. Hodasi
Keyword(s):  
Rapid Growth ◽  
Egg Production ◽  
Fasciola Hepatica ◽  
Age Groups ◽  
Sharp Decline ◽  
General Belief ◽  
Functional Changes ◽  
Complete Cessation ◽  
Lymnaea Truncatula ◽  
Accelerated Growth

Among the functional changes observed in L. truncatula infected with F. hepatica were those of growth, reproduction and mortality. For the first 3 weeks after infection there was no difference between the growth of infected and uninfected groups of snails. Thereafter there was a temporary accelerated growth which occurred between the fourth and seventh weeks after infection. The onset of this period of rapid growth in the different age groups of infected snails coincided with the time of migration of the rediae into the hepatopancreas. Of more significance was the influence of infection on the reproduction of the snail. There was a sharp decline in oviposition 2–3 weeks after infection, followed by a complete cessation of egg production at the end of the fifth week. Once oviposition ceased, it was not resumed and there was no self-cure. Contrary to general belief, infected groups of L. truncatula have been found to live longer than the uninfected controls. With isolated snails, however, there was a tendency for the uninfected snails to live longer than the infected ones. The possible interpretation of the discrepancies between isolated and mass cultured snails are discussed. The hepatopancreas and the gonad (ovotestis) were the two structures directly affected by the infection. Establishment of the rediae in the hepatopancreas invariably resulted in parasitic castration.

scholarly journals Aspects of Tertiary Prevention in Patients with Primary Open Angle Glaucoma

2021 ◽  
Vol 11 (9) ◽  
pp. 830
Author(s):  
Gabriel Zeno Munteanu ◽  
Zeno Virgiliu Ioan Munteanu ◽  
George Roiu ◽  
Cristian Marius Daina ◽  
Raluca Moraru ◽  
...  
Keyword(s):  
Open Angle Glaucoma ◽  
Glaucoma Patient ◽  
Age Groups ◽  
Tertiary Prevention ◽  
Effective Control ◽  
Ophthalmological Examination ◽  
Open Angle ◽  
High Frequencies ◽  
Number Of Patients ◽  
Primary Glaucoma

The purpose of the study is to assess the health of patients in the activity of tertiary prevention dedicated to preventing blindness caused by POAG (primary glaucoma with open angle and high tension) and NTG (primary glaucoma with open-angle and statistically normal tension—particular form of glaucoma with open angle) and preservation of the remaining visual function. The design of the study is epidemiological, observational, descriptive and retrospective, and uses only the data recorded in the existing records in the archives of the Ophthalmology office within the Integrated Outpatient Clinic of the Emergency Clinical Hospital of Oradea (IOCECHO) during the years 1999–2019 (anamnestic data; objective examination and paraclinical examination: intraocular pressure—IOP and visual field—VF). The methods of the study included the standardized protocol: anamnesis, physical ophthalmological examination, IOP determination, and computerized perimetry with the “Fast Threshold” strategy performed with the “Opto AP-300” perimeter. The obtained results were statistically processed with a specialized software (S.P.S.S.—I.B.M. Statistics version 22). The study examined the available data of 522 patients of which 140 were men (26.8%) and 382 were women (73.2%). The gender ratio was 0.37. In the period 1999–2019, 150,844 people with ophthalmic pathology were consulted in the Ophthalmology office of IOCECHO out of which 522 patients (0.35%) were diagnosed with primitive open-angle glaucoma, 184 people (35.2%) presented high IOP (POAG), and 338 people (64.8%) had statistically normal IOP (NTG). The annual proportion of cases diagnosed with glaucoma in the total number of patients examined was between 0.1% (2005; 2008; 2010) and 2.4% in 2012, when 101 people were detected. In the studied records, no cases of uni- and/or bilateral blindness were mentioned. The mean age of glaucoma patients at the first consultation was 60.81 ± 12.14 years with high frequencies in the 55–69 age groups and at the last consultation it was 66.10 ± 12.47 years with high frequencies in the age groups between 60–74 years. Monitoring and treatment of glaucoma patients was beneficial; IOP decreased statistically significantly: in patients with POAG by 46.16%, from 30.50 ± 7.98 mmHg to 16.42 ± 3.01 mmHg (p = 0.000) and in those with NTG by 17.44%, at 16.39 ± 3.66 mmHg at 13.53 ± 1.92 mmHG (p = 0.000). The duration of treatment and monitoring was on average 5.1 ± 3.4 years, for 184 patients (35.2%) with POAG and 5.1 ± 3.8 years for 338 patients (64.8%) with NTG. Tertiary prevention of glaucoma, by providing specialized care, ensures effective control of IOP and implicitly of the long-term evolution of the disease. IOP is the only modifiable risk factor in patients with POAG and NTG and its decrease prevents the progression of the disease and emphasizes the importance of early diagnosis and treatment. The management of the glaucoma patient consisted of: complete ophthalmological examination (subjective and objective), paraclinical examination with IOP, and VF measurement (valuable ophthalmological diagnostic tool) for disease detection and effective assessment of disease progression in order to improve the process of therapeutic decision making.

scholarly journals CAN STATURE, ABDOMINAL PERIMETER AND BMI INDEX PREDICT POSSIBLE CARDIOMETABOLIC RISKS IN FUTURE OBESITY?

2020 ◽  
Vol 33 (2) ◽  
Author(s):  
Ricardo Wallace das Chagas LUCAS ◽  
Paulo Afonso Nunes NASSIF ◽  
Fernando Issamu TABUSHI ◽  
Denise Serpa Bopp NASSIF ◽  
Bruno Luiz ARIEDE ◽  
...  
Keyword(s):  
Age Groups ◽  
Abdominal Circumference ◽  
Fat Percentage ◽  
Height Measurement ◽  
Men And Women ◽  
Functional Changes ◽  
Abdominal Perimeter ◽  
Cardiometabolic Risks ◽  
The Aesthetic ◽  
The Individual

ABSTRACT Background: Obesity changes the anatomy of the patient. In addition to the aesthetic change, the high percentage of fat determines evident functional changes. Anthropometric normality in measuring abdominal circumference and height can serve as a basis for measuring cardiometabolic risks of obesity. Aim: To verify if it is possible to determine parameters of normality between waist and height in people with normal BMI and fat percentages, to serve as a basis for assessing risks for obesity comorbidities. Methods: A sample of 454 individuals with BMI and percentages of fat considered within the normal range was extracted. It was divided into age groups for both men and women between 18 and 25; 26 to 35; 36 to 45; 46 to 55; 56 to 65. A total of 249 men and 205 women were included. Results: Regarding the percentage of height as a measure of the abdominal perimeter, the total female sample had an average of 44.2±1.1% and the male 45.3%+1.5. For women, this percentage determined the equation of the waist-height ratio represented by X=(age+217) / 5.875, and for men X=(age+190.89) / 5.2222. “X” represents the percentage of the height measurement so that the individual falls into the category of adequate percentage of fat and BMI. Conclusion: Between the stature of adult men and women with normal fat percentage and BMI, there is a common numerical relationship, with is on average 44% for women and 45% for men.

scholarly journals Physiological adaptation of modern Ukrainian preschoolers

2013 ◽  
Vol 7 (4) ◽  
pp. 4-9
Author(s):  
Olha Fedortsiv ◽  
Nataliia Luchyshyn
Keyword(s):  
Cardiovascular System ◽  
Developmental Disorders ◽  
Age Groups ◽  
Individual Development ◽  
Physiological Adaptation ◽  
Rate Pressure Product ◽  
Noninvasive Methods ◽  
Functional Changes ◽  
Physical Burden ◽  
System Functioning

Introduction: High demands of modern social environment to the child’s individual development are connected with their health decline and wide variation of individual capabilities. Because of such inconsistency decreased functional abilities are being observed in preschoolers. It leads mainly to health problems and developmental disorders. Body adaptive properties are considered to be the integral indicator of health. Researches find high prevalence of the lack of adaptation among children of different age groups which might lead to low quality of life.Aim of the study: The aim of the research was to estimate preschooler’s cardiovascular system functioning and the adaptation abilities based on the examples of children from Tarnopol, Ukraine.Material and methods: 170 healthy preschoolers were among the participants of the research. Anthropometry and the assessment of some hemodynamic parameters were performed to draw conclusions about the level of their cardiovascular capacity.Results: Only 54.7% of the examined children reflect the satisfactory level of cardiovascular system adaptation. The deviations mainly result from high BMI, Rate Pressure Product and abnormal reaction of the autonomic nervous system after a squatting test.Conclusions: Simple noninvasive methods (functional changes index, pulse rate and blood pressure and the indicator of arteries’ pressure) help to identify children with reduced circulatory response to stress and physical burden.

Visual receptive field properties in kitten pretectal nucleus of the optic tract and dorsal terminal nucleus of the accessory optic tract

1993 ◽  
Vol 70 (2) ◽  
pp. 814-827 ◽  
Author(s):  
C. Distler ◽  
K. P. Hoffmann
Keyword(s):  
Discharge Rate ◽  
Age Groups ◽  
Optic Tract ◽  
Visual Response ◽  
Stimulus Movement ◽  
Cortical Input ◽  
Preferred Direction ◽  
Pretectal Nucleus ◽  
Adult Cats ◽  
Contralateral Eye

1. Neurons in the pretectal nucleus of the optic tract (NOT) and dorsal terminal nucleus of the accessory optic tract (DTN) were recorded in anesthetized and paralyzed kittens on postnatal days 18 to 48 (P18-P48) as well as in adult cats. 2. Spontaneous as well as stimulus driven discharge rates of NOT-DTN neurons in the youngest kittens (P18-P23) are significantly lower than in older kittens (P27-P33) or adult cats. 3. Visual latencies of NOT-DTN neurons in P18-P23 kittens are significantly longer than in P27-P33 kittens. They further decrease as the animals reach adulthood. 4. Already in the youngest animals recorded in this experimental series (P18) NOT-DTN neurons were selective for ipsiversive horizontal stimulus movement. When expressed as the difference between response strength during stimulation in the preferred and the nonpreferred direction, P18-P23 NOT-DTN neurons are less direction selective than NOT-DTN cells in older animals. However, the normalized directional tuning expressed as percent change in discharge rate per degree change in stimulus direction away from the preferred direction (where discharge rate is set 100%) is about equal in all age groups. 5. NOT-DTN neurons in P18-P23 kittens respond to a rather limited range of stimulus speeds with an optimum at approximately 10 degrees/s. In P27-P33 kittens, NOT-DTN neurons increase their responsive range to higher stimulus speeds. As the animals approach adulthood, the range of effective stimulus speeds further broadens to include very low ones. 6. In P18-P23 kittens, the majority of NOT-DTN neurons is exclusively activated by the contralateral eye; only a few neurons receive an additional input from the ipsilateral eye. In P27-P48 kittens, the influence of the ipsilateral eye has significantly increased but with the majority of NOT-DTN cells still being dominated by the contralateral eye. Finally, in adults, a further strengthening of the ipsilateral input leads to a more binocularly balanced input to NOT-DTN cells. 7. Electrical stimulation in areas 17 and 18 did not elicit orthodromic action potentials in NOT-DTN neurons before P27. Thus the cortical input to the NOT-DTN in kittens becomes functional only at 4 wk of age. 8. In conclusion, the significant changes of visual response properties of NOT-DTN neurons coincide with the time when the cortical input to the NOT-DTN becomes functional.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Aortae of Young Rats with Metabolic Syndrome Exhibit Enhanced Vasoconstrictor Activity Than Older Rats

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
R H Ali ◽  
N M B Gamil ◽  
A M Abdelrahman ◽  
M A Ahmed ◽  
G K Megahed ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Young Adult ◽  
Fasting Blood Glucose ◽  
Age Groups ◽  
Female Rats ◽  
Control Group ◽  
Albino Rats ◽  
Functional Changes ◽  
Vasoconstrictor Response ◽  
Nitrite Content

Abstract Background Metabolic syndrome (MetS) causes pathological remodeling of the heart and adjacent vessels. The functional changes in the big vessels in different age groups had not been fully delineated. Aim of the work The present study was planned to investigate aortic vasodilator and vasoconstrictor reactivity in young, adult and old female rats with MetS. Design: The experimental study was performed on 90 female albino rats randomized into 6 groups: young, adult and old rats with MetS and their respective control groups. Methods MetS was induced by feeding rats 41% fructose -containing diet and giving fructose solution (5 g fructose in 4 ml distilled water/day) by gavage in two sessions (2 ml/session). On the 8th week, all rats were sacrificed and were subjected to determination of body weight (BW), body mass index (BMI), absolute and relative visceral fat weight (VF), fasting blood glucose (FBG), plasma insulin (PI), homeostasis model of insulin resistance (HOMA-IR) and plasma lipid profile. All rats’ aortae were subjected to study of vascular reactivity to Potassium chloride (KCL), phenylephrine (PE) and acetyl choline (A.Ch) as well as estimation of nitrite content. Results On the 8th week of the study, all MetS groups developed criteria of metabolic syndrome as evidenced by the significant increase in final BW, BMI, absolute and relative VF weights, FBG, PI and HOMA-IR compared to their control group values. Also, MetS rat groups exhibited evident dyslipidemia in the form of significant increase in plasma levels of triglycerides, total cholesterol and significant decrease in HDL-cholesterol compared to their control group values. Aortae of young and adult MetS rat groups showed significant increase in their vasoconstrictor response to KCl and PE and decrease in A.Ch/KCL% and A.Ch/PE % compared to their controls, while old MetS rat group showed significantly increased vasoconstrictor response only to KCL compared to their controls. When compared to each other, young age MetS group had significantly higher vasoconstrictor response to PE compared to old MetS group despite comparable nitrite content. Conclusion Met.S causes functional vascular changes in all age groups with unexpectedly enhanced vasoconstrictor response in the young group compared to old.

Representation of sound frequency and laterality by units in central nucleus of cat inferior colliculus

1979 ◽  
Vol 42 (6) ◽  
pp. 1626-1639 ◽  
Author(s):  
M. N. Semple ◽  
L. M. Aitkin
Keyword(s):  
Inferior Colliculus ◽  
Three Dimensions ◽  
Central Nucleus ◽  
Interaction Patterns ◽  
Low Frequencies ◽  
High Frequencies ◽  
Unit Classes ◽  
Heterogeneous Interaction ◽  
Phase Sensitive ◽  
Adult Cats

1. The discharges of 632 units were isolated extracellularly during 42 penetrations of the central nucleus of the inferior colliculus (ICC) in 21 adult cats lightly anesthetized with pentobarbital and ketamine. Microelectrode penetrations were directed from caudal to rostral through ICC, parallel to the Horsley-Clarke (H-C) horizontal and sagittal planes. 2. The threshold best frequency (BF) and binaural response properties were examined for each unit, with the aim of elucidating the organization of these discharge characteristics within ICC. 3. Binaural unit classes consisted of monaural (contralateral) (EO), binaurally phase-sensitive (delay), contralateral excitatory/ipsilateral inhibitory (EI), binaurally excitatory (EE), and other more heterogeneous interaction patterns (other). 4. Detailed histological reconstruction of electrode tracks allowed the recording site for each unit to be related to the three dimensions of ICC. This structure was divided into three lateromedial and three rostrocaudal blocks such that each block contained a similar number of units, enabling meaningful statistical comparisons. Low (3.2 kHz greater than BF) and high (3.2 kHz less than BF) best-frequency classes provided a correlate of dorsoventral location. 5. The arrangements of BFs within ICC were found to be compatible with a model of this structure in which units having similar BFs are organized into layers lying in the H-C horizontal plane medially and gradually tilting in both a ventrolateral and ventrorostral direction. Low frequencies are concentrated dorsally and laterally; high frequencies, ventrally and medially. A rostrocaudal BF difference arises only in lateral aspects of the ICC, where lower frequencies are encountered rostrally. 6. Binaural response classes were distributed differentially throughout ICC. Thus, EO units were concentrated caudally, ventrally, and laterally, while delay units were in greatest numbers rostrally, dorsally, and laterally--almost totally segregated from EO and EI units. The latter populations overlapped ventrally and laterally, but EI units were in greatest density rostrally. The EE class occurred throughout the nucleus, but was most common medially. 7. It is suggested that the differential distributions of binaural responses reflect a partial segregation of the afferents, arising in the superior olive and cochlear nucleus, which terminate in ICC. The central nucleus of the inferior colliculus thus may be composed of several functionally segregated subregions contained within a common tonotopic organization.

scholarly journals Functional anatomy of the lacrimal gland in African black ostrich Struthio camelus domesticus in the embryonic and postnatal period

2015 ◽  
Vol 82 (1) ◽  
Author(s):  
Joanna Klećkowska-Nawrot ◽  
Karolina Goździewska-Harłajczuk ◽  
Renata Nowaczyk ◽  
Krzysztof Krasucki
Keyword(s):  
Morphological Changes ◽  
Periodic Acid ◽  
Age Groups ◽  
Functional Anatomy ◽  
Postnatal Period ◽  
Age Group ◽  
Periodic Acid Schiff ◽  
Struthio Camelus ◽  
Aldehyde Fuchsin ◽  
African Black

The aim of the present study was morphological and histochemical analysis of the lacrimalgland (LG) in African black ostrich Struthio camelus domesticus in the embryonic and postnatalperiod. Studies were conducted on 50 ostriches aged between the 28th day of incubation until7 months old. Tissue sections were stained with haematoxylin and eosin, Azan trichrome,periodic acid-Schiff, Alcian blue pH 2.5, aldehyde fuchsin and Hale’s dialysed iron. The LGin ostrich was classified as a tubulo-acinar type. The primordia of the lobes were determinedin the LG structure on the 28th day of incubation, whilst the weakly visible lobes with aciniand tubules were observed on the 40th day of incubation. Morphometric studies of the LGshowed steady growth, characterised by an increase in both length and width. Histometricmeasurements of lobe size showed little difference between the first, second and third agegroups, whilst in the fourth age group a marked increase in size of lobes was observed.The study showed that, apart from morphological changes, during the growth of the LGthe character of acid mucopolysaccharides changed. Sulphated acid mucopolysaccharideswere indicated, particularly with aldehyde fuchsin (AF) staining in the fourth age group.The Hale’s dialysed iron (HDI) staining showed a low concentration of carboxylated acidmucopolysaccharides in the first and second age groups and a higher concentration in thethird and fourth age groups. Periodic acid-Schiff staining (PAS)-positive cells were observedin each age group, but only a small number of cells with a weakly PAS-positive reaction weredemonstrated in the first age group.

scholarly journals Stimulus transformation into motor action: dynamic graph analysis reveals a posterior-to-anterior shift in brain network communication of older subjects

2020 ◽  
Author(s):  
Nils Rosjat ◽  
Bin A. Wang ◽  
Liqing Liu ◽  
Gereon R. Fink ◽  
Silvia Daun
Keyword(s):  
Age Groups ◽  
Brain Network ◽  
Hemispheric Lateralization ◽  
Dynamic Graph ◽  
Movement Initiation ◽  
Motor Action ◽  
Low Frequencies ◽  
Functional Changes ◽  
Age Related ◽  
Older Subjects

AbstractCognitive performance slows down with increasing age. This includes cognitive processes that are essential for the performance of a motor act, such as the slowing down in response to an external stimulus. The objective of this study was to identify aging-associated functional changes in the brain networks that are involved in the transformation of external stimuli into motor action. To investigate this topic, we employed dynamic graphs based on phase-locking of Electroencephalography signals recorded from healthy younger and older subjects while performing a simple visually-cued finger-tapping task. The network analysis yielded specific age-related network structures varying in time in the low frequencies (2-7 Hz), which are closely connected to stimulus processing, movement initiation and execution in both age groups. The networks in older subjects, however, contained several additional, particularly interhemispheric, connections and showed an overall increased coupling density. Cluster analyses revealed reduced variability of the subnetworks in older subjects, particularly during movement preparation. In younger subjects, occipital, parietal, sensorimotor and central regions were - temporally arranged in this order - heavily involved in hub nodes. Whereas in older subjects, a hub in frontal regions preceded the noticeably delayed occurrence of sensorimotor hubs, indicating different neural information processing in older subjects.All observed changes in brain network organization, which are based on neural synchronization in the low frequencies, provide a possible neural mechanism underlying previous fMRI data, which report an overactivation, especially in the prefrontal and pre-motor areas, associated with a loss of hemispheric lateralization in older subjects.

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