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1.
Mar Drugs ; 22(5)2024 May 16.
Article in English | MEDLINE | ID: mdl-38786616

ABSTRACT

In an attempt to reduce such decay induced by pathogenic causes, several studies investigated the effectiveness of nanoparticles (NPs) that play a vital role in saving food products, especially fruits. Current research delves into biogenic silver nanoparticles (using marine alga Turbinaria turbinata (Tt/Ag-NPs) and their characterization using FT-IR, TEM, EDS, and zeta potential. Some pathogenic fungi, which cause fruit spoilage, were isolated. We studied the impact of using Tt/Ag-NPs to protect against isolated fungi in vitro, and the influence of Tt/Ag-NPs as a coating of tomato fruit to protect against blue mold caused by Penicillium italicum (OR770486) over 17 days of storage time. Five treatments were examined: T1, healthy fruits were used as the positive control; T2, healthy fruits sprayed with Tt/Ag-NPs; T3, fruits infected with P. italicum followed by coating with Tt/Ag-NPs (pre-coating); T4, fruits coated with Tt/Ag-NPs followed by infection by P. italicum (post-coating); and T5, the negative control, fruits infected by P. italicum. The results displayed that Tt/Ag-NPs are crystalline, spherical in shape, with size ranges between 14.5 and 39.85 nm, and negative charges. Different concentrations of Tt/Ag-NPs possessed antifungal activities against Botrytis cinerea, Rhodotorula mucilaginosa, Penicillium expansum, Alternaria alternate, and Stemphylium vesicarium. After two days of tomatoes being infected with P. italicum, 55% of the fruits were spoilage. The tomato fruit coated with Tt/Ag-NPs delayed weight loss, increased titratable acidity (TA%), antioxidant%, and polyphenol contents, and decreased pH and total soluble solids (TSSs). There were no significant results between pre-coating and post-coating except in phenol contents increased in pre-coating. A particular focus is placed on the novel and promising approach of utilizing nanoparticles to combat foodborne pathogens and preserve commodities, with a spotlight on the application of nanoparticles in safeguarding tomatoes from decay.


Subject(s)
Antifungal Agents , Fruit , Metal Nanoparticles , Penicillium , Silver , Solanum lycopersicum , Penicillium/drug effects , Solanum lycopersicum/microbiology , Metal Nanoparticles/chemistry , Silver/pharmacology , Silver/chemistry , Fruit/chemistry , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Food Preservation/methods
3.
Parasitol Res ; 112(7): 2503-10, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23604566

ABSTRACT

Camels are very important livestock particularly in arid and semiarid lands. The oestrid fly, Cephalopina titillator (Clark), causes nasopharyngeal myiasis in camels, and it is widely distributed in many camel breeding areas triggering health hazards and severe economic losses in camels. The prevalence of infestation of camels (slaughtered at Tokh's slaughterhouse, Qalyubia Governorate, Egypt, during the period from September 2011 to March 2012) was 41.67 % (100 out of 240). Most infested camels developed clinical signs of nasal discharge, restlessness, loss of appetite, difficulty in breathing, frequent sneezing, and snoring. Postmortem examination of infested camels explained that breathing of the animal is greatly impaired because of blockage of the nasopharynx by larvae and/or mucofibrinous secretions. The larval count per camel ranged from 1 to 250 (mean 28.45 ± 6.48). In vitro larval immersion tests were carried out to determine the efficacy of doramectin (0.003 %) as well as some essential oils (50 % each) such as lavender, camphor, and onion oils against the second and third larval stages (L2 and L3) of C. titillator. Another trial had been done for imitating what could happen if the area around camels were treated with an insecticide or an insect repellent. All treated L2 died 18 h posttreatment (PT) with both doramectin and lavender, and 100 % mortality was reached for L3 after 24 and 30 h PT with lavender and doramectin, respectively. Doramectin and lavender induced the highest response against C. titillator as their lethal time (LT50) values after treatment of L2 were 3.40 and 3.60 h, respectively, and those of L3 were 4.99 and 5.53 h, respectively. Against both L2 and L3 of C. titillator and based on LT50 values of onion oil and those of other applied materials, doramectin and lavender oil were four times more effective than onion oil, and camphor oil was two times more effective than onion oil. Based on LT50 values of essential oils and those of doramectin, as a reference substance, the relative speed of efficacy indicated that camphor and onion oils were, respectively, two and four times less effective than doramectin and lavender. With regard to fumigant technique, neither the insecticide, New Pyrosol, nor the insect repellent, Keto, was effective in controlling C. titillator larvae. Our results indicated that doramectin and lavender could be selected as drugs of choice for controlling C. titillator, but it is not permitted to use doramectin on dairy animals during lactation. Lavender (50 %) has a great potential to be developed as a novel larvicide and could be used as nasal drench against nasal botfly which will reflect on camel production and the national economy.


Subject(s)
Diptera/drug effects , Insecticides/pharmacology , Ivermectin/analogs & derivatives , Myiasis/veterinary , Nasal Cavity/parasitology , Oils, Volatile/pharmacology , Animals , Biological Assay , Camelus , Egypt , Insect Repellents/pharmacology , Ivermectin/pharmacology , Larva/drug effects , Myiasis/parasitology , Myiasis/pathology , Parasite Load , Survival Analysis
4.
Int J Dermatol ; 50(2): 187-94, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21244384

ABSTRACT

BACKGROUND: Myiasis caused by Lucilia sericata (Diptera: Calliphoridae) is widely distributed throughout the world and affects both humans and animals. In addition, L. sericata larvae and adults may play a role in spreading causal agents of mycobacterial infections. Therefore, it is important to establish new and safe alternative methods of controlling this blowfly. METHODS: The insecticidal effectiveness of four commercially available essential oils [lettuce (Lactuca sativa), chamomile (Matricaria chamomilla), anise (Pimpinella anisum), rosemary (Rosmarinus officinalis)] against third larval instars of L. sericata was evaluated. The effects of sublethal concentrations of these oils on pupation rates, adult emergences, sex ratios, and morphological anomalies were also determined. RESULTS: The oils were highly toxic to L. sericata larvae, with median lethal concentrations (LC(50) ) of 0.57%, 0.85%, 2.74%, and 6.77% for lettuce, chamomile, anise, and rosemary oils, respectively. Pupation rates were markedly decreased after treatment with 8% lettuce oil, and adult emergence was suppressed by 2% lettuce and chamomile oils. Morphological abnormalities were recorded after treatment with all tested oils, and lettuce was the major cause of deformation. There was a predominance of males over females (4 : 1) after treatment with lower concentrations of chamomile and rosemary; such a skew toward males would lead to a population decline. CONCLUSIONS: The four tested oils are inexpensive and may represent new botanical insecticides for controlling blowflies.


Subject(s)
Diptera , Insect Control/methods , Insecticides , Myiasis/prevention & control , Oils, Volatile , Animals , Chamomile/chemistry , Female , Larva , Lactuca/chemistry , Male , Myiasis/transmission , Pimpinella/chemistry , Pupa , Rosmarinus , Sex Ratio
5.
Neuroreport ; 10(6): 1167-70, 1999 Apr 26.
Article in English | MEDLINE | ID: mdl-10363918

ABSTRACT

To investigate the physiological role of visual gamma-band oscillation (GBO), we calculated the event-related dynamics of the EEG power-spectrum for paired visual stimuli (S1 and S2) with or without attention in 12 subjects. The visual stimuli elicited transient increases in the GBO power (around 40 Hz), which were maximal over the parietal area. The peak GBO increase appeared around 300 ms after stimulus onset, but its latency was shorter after S1 and longer after S2 under the 'with attention' than under the 'without attention' condition. This transient increase in the visual GBO is thought to reflect attention and to reset the activity of the visual system in preparation for a new stimulus.


Subject(s)
Attention/physiology , Electroencephalography , Evoked Potentials, Visual/physiology , Motion Perception/physiology , Adult , Analysis of Variance , Female , Humans , Male , Middle Aged , Oscillometry , Photic Stimulation
6.
Neurosci Res ; 33(3): 215-22, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10211765

ABSTRACT

To investigate the gamma band activity relating to the discrimination process and motor behavior in the human brain, the event-related dynamics of the EEG spectrum was calculated during the visual GO/NOGO hand movement task and a control task (the visual element of the GO/NOGO task only) in eight subjects. The subjects were instructed to push (GO) or not to push (NOGO) a microswitch according to different visual stimuli and 21-channel scalp EEGs were recorded. The time courses of the power spectra after the stimuli were calculated using the fast Fourier transform for each condition (GO, NOGO and the control task), and were compared statistically between the conditions. The results suggested that a high gamma band oscillation, occurring at the frontal and left parieto-occipital areas at around 90 ms after the stimuli, relates to the discrimination process. Under the GO condition, this oscillation continued until 140 ms, and a subsequent oscillation occurred over the motor areas at around 200 ms, which seemed to be related to the motor action. On the other hand, under the NOGO condition, a low gamma band oscillation occurred in the central area at around 230 ms, which seemed to be related to the inhibition process.


Subject(s)
Brain/physiology , Electroencephalography , Motor Activity/physiology , Movement/physiology , Psychomotor Performance/physiology , Thinking/physiology , Adult , Female , Hand/innervation , Humans , Male , Oscillometry , Photic Stimulation , Reaction Time , Scalp/innervation , Visual Perception
7.
Neurosci Res ; 31(4): 265-71, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9809585

ABSTRACT

To investigate the functional connection of brain areas under motor inhibition, the event-related coherence (ERCoh) of the electroencephalogram (EEG) was calculated for 10 subjects who were asked to perform a visual discrimination (GO/NO-GO) task. The subjects were instructed to push (GO) or not to push (NO-GO) a micro-switch according to different visual stimuli. Twenty-one-channel scalp EEGs were recorded and the surface Laplacians were calculated at F3, F4, C3, C4, P3 and P4 using the source derivation method. The time-courses of the inter- and intra-hemispheric coherence were calculated using the fast Fourier transform for each condition (GO or NO-GO), and were compared statistically between the two conditions. The results suggest that the ERCoh under the NO-GO condition consisted of two components; alpha band synchronization between bilateral frontal areas and theta band synchronization among bilateral frontal, central and parietal areas. It is likely that the former is related directly to the decision not to move, and the latter is related to the motor inhibition process.


Subject(s)
Cortical Synchronization , Motor Cortex/physiology , Neural Inhibition/physiology , Adult , Discrimination Learning , Evoked Potentials/physiology , Female , Fourier Analysis , Hand/physiology , Humans , Male , Middle Aged , Movement/physiology , Photic Stimulation , Reaction Time/physiology
8.
Jpn J Physiol ; 48(6): 493-7, 1998 Dec.
Article in English | MEDLINE | ID: mdl-10021503

ABSTRACT

Hemispheric dominance in contextual recognition is now under discussion. Auditory event-related potentials (ERPs) with a contextual decision task were recorded to study hemispheric dominance by using the wave energy and amplitudes of N400 for eight native volunteers. Two types of 80 sentences with four clauses were used as the structure: [subject] + [object or complement] + [object] + [two-syllable verb]. One type was congruent and the other deviated at the terminal clause as an incongruent sentence. Twenty-one channel ERPs were triggered at the verbs and recorded during -200 and 1,000 ms, with a noncephalic reference from 0.05 to 30 Hz. The wave energy was calculated as mean square potentials and was normalized with the background activity (pretrigger 200 ms). The amplitudes of N400 showed significant differences between the incongruent and congruent sentences, but the hemispheric dominance for the amplitudes of N400 was not significant between the incongruent and congruent sentences. Reaction times with the index finger to respond to the deviated verbs were 470.0 (mean) +/- 42.5 (SD) ms. The maximum normalized wave energy within the mean reaction time showed significant differences between the incongruent and congruent sentences, and the left hemispheric energy was shown to be significantly higher than the right one.


Subject(s)
Evoked Potentials, Auditory/physiology , Functional Laterality , Adult , Auditory Perception , Humans
9.
Doc Ophthalmol ; 97(1): 1-7, 1998.
Article in English | MEDLINE | ID: mdl-10710237

ABSTRACT

Binocular interaction for a central field was studied with transient scalp visual evoked cortical potentials (VECPs) using two light-emitting-diodes. VECPs were obtained for binocular and monocular visions with dominant and non-dominant eyes, and arithmetical sums of monocular VECPs with dominant and non-dominant eyes were calculated. Amplitude and latency of remarkable initial three peaks were tested with the multivariate analysis of variance. Significant differences were noted among the four VECPs. Pairwise comparisons showed that (1) the amplitude of the first peak for the binocular VECPs was larger than that for the monocular VECPs but smaller than that for the sum-VECPs; the latency of the first peaks for the binocular VECPs were earlier than that for the monocular VECPs with the non-dominant eye; (2) the amplitude of the first negative peak for the sum-VECPs was larger than that for the binocular VECPs, and the peak latency for the sum-VECPs showed later than that for the binocular VECPs; (3) the amplitude of the second positive peak for the binocular VECPs and monocular VECPs with the dominant eye was larger than that with the non-dominant eye, but smaller for the binocular VECPS than that for the sum-VECPs; the latency for the binocular VECPs showed earlier than that for the monocular VECPs with the dominant eye and for the sum-VECPs. Binocular suppression was noted in amplitude for the three peaks and binocular facilitation was noted in latency for the latter two peaks.


Subject(s)
Evoked Potentials, Visual/physiology , Vision, Binocular/physiology , Visual Cortex/physiology , Adult , Humans , Photic Stimulation , Vision, Monocular/physiology
10.
Neurosci Lett ; 233(2-3): 117-20, 1997 Sep 19.
Article in English | MEDLINE | ID: mdl-9350846

ABSTRACT

Event-related coherence of the EEG was calculated for 10 subjects performing a visual discrimination GO/NO-GO task. The subjects were instructed to push (GO) or not to push (NO-GO) a button according to visual stimuli. Twenty-one-channel scalp EEGs were recorded and the surface Laplacian was calculated using the source derivation method. The time courses of the coherence between F3 and F4, C3 and C4, and P3 and P4 were calculated using the fast Fourier transform for each task and were compared between conditions. Statistical analysis showed that coherence in the NO-GO condition became significantly higher than that in the GO condition between F3 and F4. The synchronization between bilateral dorsolateral frontal areas might therefore play an important role in the motor inhibition process.


Subject(s)
Brain Mapping/methods , Discrimination Learning/physiology , Electroencephalography , Evoked Potentials, Visual/physiology , Psychomotor Performance/physiology , Adult , Analysis of Variance , Female , Humans , Male , Middle Aged
11.
Brain Res ; 532(1-2): 339-41, 1990 Nov 05.
Article in English | MEDLINE | ID: mdl-2282528

ABSTRACT

Correlation between respiratory movement and neural discharges of antidromically identified 20 crossed spinocerebellar tract (SCT) neurones in the T8-11 segments was examined in the anaesthetized, paralysed cat. Activity of 11 neurones of them was related to phrenic nerve activity; 7 neurones increased and 4 decreased their activity during the active phase of the phrenic nerve. Their rhythmic activity remained even after artificial ventilation was turned off, indicating the central genesis of their rhythmic activity. By comparing discharge patterns with the ventilator on and off, it is suggested that half of these crossed SCT neurones appear to receive additional inputs from the periphery. Neurones which increased their firing rate during phrenic nerve activity tend to respond with decrease discharge to passive chest inflation, and vise versa.


Subject(s)
Cerebellum/physiology , Neurons/physiology , Respiratory Mechanics/physiology , Spinal Cord/physiology , Animals , Cats , Cerebellum/cytology , Neural Pathways/physiology , Phrenic Nerve/physiology , Respiration, Artificial , Spinal Cord/cytology , Thorax
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