110 research outputs found
Investigation of a parasitic outbreak of Lernaea cyprinacea Linnaeus (Crustacea: Copepoda) in Cyprinid fish from Choghakhor lagoon
The main objectives of this study were to study the parasitic infestation of Lernaea cyprinacea in 4 cyprinids from the Choghakhor Lagoon, Chaharmahal - Bakhtyari Province, west of Iran. A total of 180 cyprinids including Cyprinus carpio (n=101), Carassius auratus (n=47), Capoeta aculeata (n=10) and Alburnus alburnus (n=22) caught, and were studied for Lernaea cyprinacea infestation. Prevalence (C. carpio 61.4, C. auratus 87.2, C. aculeata 70 and A. alburnus 68.2), intensity of infection (C. carpio range 1 to 5, mean 2.1; C. auratus range 1 to 6, mean 1.9; C. aculeata range 1 to 5, mean 2.4; A. alburnus range 1 to 2, mean 1.1), and abundance (C. carpio 1.3, C. auratus 1.6, C. aculeata 1.7 and A. alburnus 0.8) varied with the fish species. A statistically significant difference was found between infestation by L. cyprinacea and fish species (p=0.01), although no statistically significant difference was found between infestation and weight, length and age of the studied fishes (p>0.05). The prevalence was also significantly different (p=0.0) in studying seasons. Population dynamics of L. cyprinacea on fish hosts was studied. The results show that the preferred site of the parasite was body lateral surfaces followed by caudal, dorsal, pectoral and anal fins (P=0.0)
Impact of bilateral, single‐sided and asymmetrical hearing loss on cognitive functions
Aim of the study was to investigate the impact of single sided, asymmetrical and bilateral sensorineural hearing loss on cognitive and psychological functions of postlingually hearing impaired adults
Editorial: New challenges and future perspectives in neurodegeneration
Over the last decade, there has been growing interest and important developments in neurodegeneration research. These advances have been fostered by improvements in the research techniques that enable us to collect novel data understand the disease process(es) and underlying mechanisms better. In this Research Topic, we encouraged researchers to summarize their state-of-the-art methods, findings, and the main challenges that the field of neurodegeneration is facing..
Study of effect of arbuscular mycorrhiza (Glomus intraradices) fungus on wheat under nickel stress
ArticleIn many regions of the world soils are contaminated with heavy metals and therefore
restricted in their use. For instance, the absorption of nickel (Ni) in the tissue
of plants increase
the plant’s metabolism and cause physiological disorders or even death. Arbuscular mycorrhizal
fungi are known to enhance the tolerance of host plants to abiotic and biotic stress. Thus, we
investigated the potential of the arbuscular m
ycorrhizal fungi
Glomus intraradices
to mitigate
deleterious effects of Ni in wheat. The experiment was conducted using four levels of Ni (0, 60,
120 and 180
mg
per
kg of soil) and two levels of mycorrhizal fungi application (with and without
Glomus intrar
adices
). Nickel stress significantly decreased seed number per spike, thousand
-
seed
weight, seed yield per plant, concentration of chlorophyll a and b. At the same time, we found
increased catalase (CAT) enzyme activity and dityrosine (DT) treatments.
Mycorrhizal fungi
application attenuated Ni effects, i.e. fungal presence increased seed number per spike, thousand
-
seed weight, chlorophyll a and b. Furthermore mycorrhizal fungi application reduce CAT enzyme
activity and DT. In general, our results sugge
st that mycorrhizal fungi application reduces harmful
effects of Ni stress in wheat
Comparison of auditory steady-state responses with conventional audiometry in older adults
Behavioral measures, such as pure-tone audiometry (PTA), are commonly used to determine hearing thresholds, however, PTA does not always provide reliable hearing information in difficult to test individuals. Therefore, objective measures of hearing sensitivity that require little-to-no active participation from an individual are needed to facilitate the detection and treatment of hearing loss in difficult to test people. Investigation of the reliability of the auditory steady-state response (ASSR) for measuring hearing thresholds in older adults is limited. This study aimed to investigate if ASSR can be a reliable, objective measure of frequency specific hearing thresholds in older adults. Hearing thresholds were tested at 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz in 50 participants aged between 60 and 85 years old, using automated PTA and ASSR. Hearing thresholds obtained from PTA and ASSR were found to be significantly correlated (p < .001) in a cohort consisting of participants with normal hearing or mild hearing loss. ASSR thresholds were significantly higher as compared to PTA thresholds, but for the majority of cases the difference remained within the clinically acceptable range (15 dB). This study provides some evidence to suggest that ASSR can be a valuable tool for estimating objective frequency-specific hearing thresholds in older adults and indicate that ASSR could be useful in creating hearing treatment plans for older adults who are unable to complete behavioral PTA. Further research on older adults is required to improve the methodological features of ASSR to increase consistency and reliability, as well as minimize some of the limitations associated with this technique
Investigating the probable consequences of super absorbent polymer and mycorrhizal fungi to reduce detrimental effects of lead on wheat (Triticum aestivum L.)
ArticleIn many parts of the world, agricultural use of soils is restricted due to heavy metal
contamination. Absorption of heavy metals, such as (Pb), in the tissue of plants increases the
plant’s metabolism and causes physiological disorders or even death. In order to study the
potential of super absorbent polymers (SAP) and mycorrhiza fungi application to mitigate adverse
effects of lead (Pb) on wheat, a greenhouse experiment was conducted. The experiment was setup
as a completely randomized design, with two treatments arranged in a factorial scheme with three
levels of lead (0, 100 and 200 mg per kg soil) and four levels of SAP and mycorrhiza fungi
application (without SAP and mycorrhiza fungi application, SAP application alone, mycorrhiza
fungi application alone, SAP and mycorrhiza fungi application combined). The results showed
that Pb significantly affected all parameters measured of wheat. The Pb-contamination caused a
significantly decreasing in plant height, total dry weight per plant and total chlorophyll contents.
And also, the results indicated that the combined use of superabsorbent and mycorrhiza reduced
the amount of superoxide dismutase enzyme. As well as, our results show that the application of
super absorbent polymer and mycorrhizal fungi seems to be a promising path to reduce
detrimental effects of heavy metal pollution of agricultural soils on plant performance.http://dx.doi.org/10.15159/ar.18.00
Understanding the Relationship Between Age-Related Hearing Loss and Alzheimer’s Disease: A Narrative Review
Evidence suggests that hearing loss (HL), even at mild levels, increases the long-term risk of cognitive decline and incident dementia. Hearing loss is one of the modifiable risk factors for dementia, with approximately 4 million of the 50 million cases of dementia worldwide possibly attributed to untreated HL. This paper describes four possible mechanisms that have been suggested for the relationship between age-related hearing loss (ARHL) and Alzheimer’s disease (AD), which is the most common form of dementia. The first mechanism suggests mitochondrial dysfunction and altered signal pathways due to aging as a possible link between ARHL and AD. The second mechanism proposes that sensory degradation in hearing impaired people could explain the relationship between ARHL and AD. The occupation of cognitive resource (third) mechanism indicates that the association between ARHL and AD is a result of increased cognitive processing that is required to compensate for the degraded sensory input. The fourth mechanism is an expansion of the third mechanism, i.e., the function and structure interaction involves both cognitive resource occupation (neural activity) and AD pathology as the link between ARHL and AD. Exploring the specific mechanisms that provide the link between ARHL and AD has the potential to lead to innovative ideas for the diagnosis, prevention, and/or treatment of AD. This paper also provides insight into the current evidence for the use of hearing treatments as a possible treatment/prevention for AD, and if auditory assessments could provide an avenue for early detection of cognitive impairment associated with AD
Auditory electrophysiological assessments of Alzheimer’s disease and preclinical stages: Protocol for a systematic review and meta-analysis
Introduction
Investigating auditory functions in populations at risk of developing Alzheimer’s disease (AD) using auditory neurophysiological measurements can potentially identify a crucial and sensitive diagnostic window of opportunity in preclinical AD. Auditory electrophysiological assessments have gained interest as possible tools for early diagnosis of AD. This paper outlines the protocol that will be used to systematically review the published literature currently available on auditory electrophysiological assessments that have been used to assess the auditory functions of adults over the age of 60 years diagnosed with AD or its preclinical stages.
Methods and analysis
All full-length peer-reviewed publications of original data that use auditory electrophysiological assessments in AD and its preclinical stages (subjective cognitive decline (SCD) and mild cognitive impairment (MCI)) will be considered in this review. The search will be performed on major electronic databases (Ovid MEDLINE, Ovid Embase, PsycINFO, PubMed, Scopus and CINAHL Plus) using keywords alone or in combination with Medical Subject Headings divided into two domains; (i) auditory tests and (ii) AD. The database search will be conducted on the 7th of May 2019. Data analysis will be completed and reported in the full review. A random effects meta-analysis will also be conducted using the Comprehensive Meta-Analysis software, V.3. This review will describe which auditory electrophysiological tests have been found to be useful in assessing the auditory function in cognitively impaired adults (MCI and AD) or adults with serious complaints about their cognition (SCD). This review will also identify and describe which auditory electrophysiological test demonstrates the most sensitivity in differentiating people at different stages of cognitive decline.
Ethics and dissemination
This systematic review focusses on analysing already available literature. Therefore, there will be no requirement for ethical approval. The systematic review findings will be disseminated through peer-reviewed publication as well as relevant media platforms, for example, conferences
A NOVEL METHOD FOR SYNTHESIS OF METASTABLE TETRAGONAL ZIRCONIA NANOPOWDERS AT LOW TEMPERATURES
Zirconia (ZrO2) nanopowder was synthesized using sucrose and fructose as a chelating agent from zirconium hydroxide. The synthesized powders were characterized by X-ray diffraction (XRD), simultaneously thermal analysis (STA), BET surface area, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The above-experimental results showed that the synthesized powders had particle sizes in the range 40-60 nm and mean crystallite sizes of 7-8 nm. Finally, in this research, chelating agents of sucrose and fructose were compared and the obtained results demonstrated that using fructose, nanopowder of zirconia with tetragonal phase was obtained
Systematic review protocol for assessing central auditory functions of Alzheimer’s disease and its preclinical stages
Introduction: A number of studies have reported an association between peripheral hearing impairment, central auditory processing and Alzheimer’s disease (AD) and its preclinical stages. Both peripheral hearing impairment and central auditory processing disorders are observed many years prior to the clinical manifestation of AD symptoms, hence, providing a long window of opportunity to investigate potential interventions against neurodegenerative processes. This paper outlines the protocol for a systematic review of studies examining the central auditory processing functions in AD and its preclinical stages, investigated through behavioural (clinical assessments that require active participation) central auditory processing tests.
Methods and analysis: We will use the keywords and Medical Subject Heading terms to search the following electronic databases: MEDLINE, PsychINFO, PubMed, Scopus, EMBASE and CINAHL Plus. Studies including assessments of central auditory function in adults diagnosed with dementia, AD and its preclinical stages that were published before 8 May 2019 will be reviewed. This review protocol will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. Data analysis and search results will be reported in the full review. This manuscript has designed the protocols for a systematic review that will identify the behavioural clinical central auditory processing measures that are sensitive to the changes in auditory function in adults with AD and its preclinical stages. Such assessments may subsequently help to design studies to examine the potential impact of hearing and communication rehabilitation of individuals at risk of AD.
Ethics and dissemination: Ethical approval is not required as this manuscript only reports the protocols for conducting a systematic review as primary data will only be reviewed and not be collected. The results of this systematic review will be disseminated through publication and in scientific conferences
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