Age‐related effect of high‐frequency photostimulation on Blood Physiological Variables in laying hens

Lutein is considered a protective nutrient against age-related macular degeneration in humans. An experiment was designed to study the long-term effect of feeding lutein in combination with flaxseed on layer performance, egg parameters, and lutein deposition in eggs and tissues. Laying hens were fed diets with 0 or 10% flax supplemented with 0, 125 or 250 ppm lutein for 11 consecutive 28-d periods beginning at 18 wk of age. Early production was reduced (P < 0.01) by feeding diets with 10% flax and when supplemented with 250 ppm lutein. Diet treatments had no effect on feed intake, egg weight or eggshell deformation. Addition of lutein to the diets significantly (P < 0.01) increased yolk color, and lutein content in the egg, liver, and the preen gland. Egg lutein content increased (P < 0.01) from a basal level of 0.10 mg to 1.60 mg 60g-1 egg by addition of lutein to the diet. Liver fat was lower (P < 0.05) in hens fed 10% flaxseed. Liver hemorrhage score was dramatically reduced (P < 0.01) in birds fed lutein. Key words: egg composition, flaxseed, lutein, layers

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Identifying Subclinical Hearing Loss: Extended Audiometry and Word Recognition in Noise

Audiology and Neurotology ◽

10.1159/000518962 ◽

2021 ◽

pp. 1-10

Author(s):

Ward R. Drennan

Keyword(s):

Word Recognition ◽

Significant Relationship ◽

High Frequency ◽

Recognition Task ◽

Normal Hearing ◽

Normal Range ◽

Closed Set ◽

Age Related ◽

High Frequency Audiometry ◽

Hearing Problems

Introduction: Normal-hearing people often have complaints about the ability to recognize speech in noise. Such disabilities are not typically assessed with conventional audiometry. Suprathreshold temporal deficits might contribute to reduced word recognition in noise as well as reduced temporally based binaural release of masking for speech. Extended high-frequency audibility (>8 kHz) has also been shown to contribute to speech perception in noise. The primary aim of this study was to compare conventional audiometric measures with measures that could reveal subclinical deficits. Methods: Conventional and extended high-frequency audiometry was done with 119 normal-hearing people ranging in age from 18 to 72. The ability to recognize words in noise was evaluated with and without differences in temporally based spatial cues. A low-uncertainty, closed-set word recognition task was used to limit cognitive influences. Results: In normal-hearing listeners, word recognition in noise ability decreases significantly with increasing pure-tone average (PTA). On average, signal-to-noise ratios worsened by 5.7 and 6.0 dB over the normal range, for the diotic and dichotic conditions, respectively. When controlling for age, a significant relationship remained in the diotic condition. Measurement error was estimated at 1.4 and 1.6 dB for the diotic and dichotic conditions, respectively. Controlling for both PTA and age, EHF-PTAs showed significant partial correlations with SNR50 in both conditions (ρ = 0.30 and 0.23). Temporally based binaural release of masking worsened with age by 1.94 dB from 18 to 72 years old but showed no significant relationship with either PTA. Conclusions: All three assessments in this study demonstrated hearing problems independently of those observed in conventional audiometry. Considerable degradations in word recognition in noise abilities were observed as PTAs increased within the normal range. The use of an efficient words-in-noise measure might help identify functional hearing problems for individuals that are traditionally normal hearing. Extended audiometry provided additional predictive power for word recognition in noise independent of both the PTA and age. Temporally based binaural release of masking for word recognition decreased with age independent of PTAs within the normal range, indicating multiple mechanisms of age-related decline with potential clinical impact.

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Uterine transcriptome analysis reveals mRNA expression changes associated with the ultrastructure differences of eggshell in young and aged laying hens

BMC Genomics ◽

10.1186/s12864-020-07177-7 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Jia Feng ◽

Hai-jun Zhang ◽

Shu-geng Wu ◽

Guang-hai Qi ◽

Jing Wang

Keyword(s):

Antigen Processing ◽

Laying Hens ◽

Late Phase ◽

Economic Loss ◽

Matrix Proteins ◽

Differentially Expressed ◽

Eggshell Formation ◽

Eggshell Quality ◽

Age Related ◽

Altered Gene

Abstract Background Lower eggshell quality in the late laying period leads to economic loss. It is a major threat to the quality and safety of egg products. Age-related variations in ultrastructure were thought to induce this deterioration. Eggshell formation is a highly complex process under precise regulation of genes and biological pathways in uterus of laying hens. Herein, we evaluated the physical, mechanical and ultrastructure properties of eggshell and conducted RNA sequencing to learn the transcriptomic differences in uterus between laying hens in the peak (young hens) and late phase (aged hens) of production. Results The declined breaking strength and fracture toughness of eggshell were observed in aged hen group compared to those in young hen group, accompanied with ultrastructure variations including the increased thickness of mammillary layer and the decreased incidence of early fusion. During the initial stage of eggshell formation, a total of 183 differentially expressed genes (DEGs; 125 upregulated and 58 downregulated) were identified in uterus of laying hens in the late phase in relative to those at peak production. The DEGs annotated to Gene Ontology terms related to antigen processing and presentation were downregulated in aged hens compared to young hens. The contents of proinflammatory cytokine IL-1β in uterus were higher in aged hens relative to those in young hens. Besides, the genes of some matrix proteins potentially involved in eggshell mineralization, such as ovalbumin, versican and glypican 3, were also differentially expressed between two groups. Conclusions Altered gene expression of matrix proteins along with the compromised immune function in uterus of laying hens in the late phase of production may conduce to age-related impairments of eggshell ultrastructure and mechanical properties. The current study enhances our understanding of the age-related deteriorations in eggshell ultrastructure and provides potential targets for improvement of eggshell quality in the late laying period.

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Female Anal Sphincter: Age-related Differences in Asymptomatic Volunteers with High-Frequency Endoanal US

Radiology ◽

10.1148/radiol.2242010985 ◽

2002 ◽

Vol 224 (2) ◽

pp. 417-423 ◽

Cited By ~ 88

Author(s):

Andrea Frudinger ◽

Steve Halligan ◽

Clive I. Bartram ◽

Ashley B. Price ◽

Michael A. Kamm ◽

...

Keyword(s):

Anal Sphincter ◽

High Frequency ◽

Age Related ◽

Asymptomatic Volunteers

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A study on the basic nature of human biological aging processes based upon a hierarchical factor solution of the age-related physiological variables

Mechanisms of Ageing and Development ◽

10.1016/0047-6374(91)90128-m ◽

1991 ◽

Vol 60 (2) ◽

pp. 153-170 ◽

Cited By ~ 12

Author(s):

E. Nakamura

Keyword(s):

Biological Aging ◽

Factor Solution ◽

Physiological Variables ◽

Age Related

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Contributing Determinants to Hearing Loss in Elderly Men and Women: Results from the Population-Based Rotterdam Study

Audiology and Neurotology ◽

10.1159/000448348 ◽

2016 ◽

Vol 21 (Suppl. 1) ◽

pp. 10-15 ◽

Cited By ~ 11

Author(s):

Stephanie C. Rigters ◽

Mick Metselaar ◽

Marjan H. Wieringa ◽

Robert J. Baatenburg de Jong ◽

Albert Hofman ◽

...

Keyword(s):

Hearing Loss ◽

High Frequency ◽

Pure Tone Audiometry ◽

Inverse Correlation ◽

Population Based ◽

Rotterdam Study ◽

Cross Sectional ◽

Men And Women ◽

Age Related ◽

Age Related Hearing Loss

To contribute to a better understanding of the etiology in age-related hearing loss, we carried out a cross-sectional study of 3,315 participants (aged 52-99 years) in the Rotterdam Study, to analyze both low- and high-frequency hearing loss in men and women. Hearing thresholds with pure-tone audiometry were obtained, and other detailed information on a large number of possible determinants was collected. Hearing loss was associated with age, education, systolic blood pressure, diabetes mellitus, body mass index, smoking and alcohol consumption (inverse correlation). Remarkably, different associations were found for low- and high-frequency loss, as well as between men and women, suggesting that different mechanisms are involved in the etiology of age-related hearing loss.

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Synaptic Transmission at the Cochlear Nucleus Endbulb Synapse During Age-Related Hearing Loss in Mice

Journal of Neurophysiology ◽

10.1152/jn.00374.2005 ◽

2005 ◽

Vol 94 (3) ◽

pp. 1814-1824 ◽

Cited By ~ 59

Author(s):

Yong Wang ◽

Paul B. Manis

Keyword(s):

Hearing Loss ◽

Synaptic Transmission ◽

Cochlear Nucleus ◽

Auditory Nerve ◽

High Frequency ◽

Nerve Activity ◽

Synaptic Release ◽

Endbulb Of Held ◽

Age Related ◽

Age Related Hearing Loss

Age-related hearing loss (AHL) typically starts from high-frequency regions of the cochlea and over time invades lower-frequency regions. During this progressive hearing loss, sound-evoked activity in spiral ganglion cells is reduced. DBA mice have an early onset of AHL. In this study, we examined synaptic transmission at the endbulb of Held synapse between auditory nerve fibers and bushy cells in the anterior ventral cochlear nucleus (AVCN). Synaptic transmission in hearing-impaired high-frequency areas of the AVCN was altered in old DBA mice. The spontaneous miniature excitatory postsynaptic current (mEPSC) frequency was substantially reduced (about 60%), and mEPSCs were significantly slower (about 115%) and smaller (about 70%) in high-frequency regions of old (average age 45 days) DBA mice compared with tonotopically matched regions of young (average age 22 days) DBA mice. Moreover, synaptic release probability was about 30% higher in high-frequency regions of young DBA than that in old DBA mice. Auditory nerve–evoked EPSCs showed less rectification in old DBA mice, suggesting recruitment of GluR2 subunits into the AMPA receptor complex. No similar age-related changes in synaptic release or EPSCs were found in age-matched, normal hearing young and old CBA mice. Taken together, our results suggest that auditory nerve activity plays a critical role in maintaining normal synaptic function at the endbulb of Held synapse after the onset of hearing. Auditory nerve activity regulates both presynaptic (release probability) and postsynaptic (receptor composition and kinetics) function at the endbulb synapse after the onset of hearing.

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