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1.
Acta Vet Scand ; 66(1): 27, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956671

ABSTRACT

BACKGROUND: Heterakis gallinarum (H. gallinarum) is a common poultry parasite that can be found in the ceca of many gallinaceous bird species, causing minor pathology and reduced weight gain. Most infections go unnoticed in commercial flocks due to the dependence on fecal egg counts, which are prone to false-negative diagnoses. Furthermore, there is a lack of research on gastrointestinal nematodes that use molecular identification methods, which could be essential for rapid diagnosis and developing efficient control approaches. As a result, the study aimed to look at the cause of mortality in layer chickens induced by H. gallinarum in Egyptian poultry farms using morphological, ultrastructural, and molecular characterization. Histopathological, immunohistochemical, and cell-mediated immune responses from damaged cecal tissues were also examined. RESULTS: Seventy bird samples from ten-layer flocks of different breeds (Native, white, and brown layers) suffering from diarrhea, decreased egg output, and emaciation were collected. Cecal samples were collected from affected and non-affected birds and were examined for parasitic diseases using light and a scanning electron microscope. The mitochondrial cytochrome oxidase 1 (COX1) gene was used to characterize H. gallinarum. Our results showed that the collected nematodal worms were identified as H. gallinarum (male and female), further confirmed by COX1 gene amplification and sequence alignment. Gene expression analysis of the inflammatory markers in infected tissues showed a significant up-regulation of IL-2, IFN-γ, TLR-4, and IL-1ß and a significant down-regulation of the anti-inflammatory IL-10. The mRNA level of the apoptotic cas-3 revealed apoptotic activity among the H. gallinarum samples compared to the control group. CONCLUSIONS: Our results implemented the use of molecular methods for the diagnosis of Heterakis, and this is the first report showing the tissue immune response following infection in layers: upregulation of IL-1ß, IFN-γ, Il-2, and TLR-4, while down-regulation of anti-inflammatory IL-10 in cecal tissue, Cas-3 apoptotic activity and Nuclear factor-κB (NF-κB)activity with immunophenotyping of T-cells in Heterakis infected tissue.


Subject(s)
Cecum , Chickens , Poultry Diseases , Typhlitis , Animals , Poultry Diseases/parasitology , Poultry Diseases/immunology , Poultry Diseases/pathology , Typhlitis/veterinary , Typhlitis/parasitology , Typhlitis/pathology , Cecum/parasitology , Cecum/pathology , Female , Immunity, Cellular , Ascaridida Infections/veterinary , Ascaridida Infections/parasitology , Ascaridoidea , Egypt
2.
Health Inf Sci Syst ; 12(1): 36, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38868156

ABSTRACT

Ocular diseases pose significant challenges in timely diagnosis and effective treatment. Deep learning has emerged as a promising technique in medical image analysis, offering potential solutions for accurately detecting and classifying ocular diseases. In this research, we propose Ocular Net, a novel deep learning model for detecting and classifying ocular diseases, including Cataracts, Diabetic, Uveitis, and Glaucoma, using a large dataset of ocular images. The study utilized an image dataset comprising 6200 images of both eyes of patients. Specifically, 70% of these images (4000 images) were allocated for model training, while the remaining 30% (2200 images) were designated for testing purposes. The dataset contains images of five categories that include four diseases, and one normal category. The proposed model uses transfer learning, average pooling layers, Clipped Relu, Leaky Relu and various other layers to accurately detect the ocular diseases from images. Our approach involves training a novel Ocular Net model on diverse ocular images and evaluating its accuracy and performance metrics for disease detection. We also employ data augmentation techniques to improve model performance and mitigate overfitting. The proposed model is tested on different training and testing ratios with varied parameters. Additionally, we compare the performance of the Ocular Net with previous methods based on various evaluation parameters, assessing its potential for enhancing the accuracy and efficiency of ocular disease diagnosis. The results demonstrate that Ocular Net achieves 98.89% accuracy and 0.12% loss value in detecting and classifying ocular diseases by outperforming existing methods.

3.
J Neurophysiol ; 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38865217

ABSTRACT

Muscle force is modulated by sequential recruitment and firing rates of motor units (MUs). However, discrepancies exist in the literature regarding the relationship between MU firing rates and their recruitment, presenting two contrasting firing-recruitment schemes. The first firing scheme, known as "onion skin", exhibits low-threshold MUs firing faster than high-threshold MUs, forming separate layers akin to an onion. This contradicts the other firing scheme, known as "reverse onion skin" or "after-hyperpolarization (AHP)", with low-threshold MUs firing slower than high-threshold MUs. To study this apparent dichotomy, we employed a high-fidelity computational model that prioritizes physiological fidelity and heterogeneity, allowing versatility in the recruitment of different motoneuron types. Our simulations indicate that these two schemes are not mutually exclusive but rather coexist. The likelihood of observing each scheme depends on factors such as the motoneuron pool activation level, synaptic input activation rates, and MU type. The "onion skin" scheme does not universally govern the encoding rates of MUs but tends to emerge in unsaturated motoneurons (cells firing < their fusion frequency that generates peak force), whereas the "AHP" scheme prevails in saturated MUs (cells firing at their fusion frequency), which is highly probable for S-type MUs. When unsaturated, FF-type MUs always show the "onion skin" scheme, while S-type MUs do not show either one. FR-type MUs are generally similar but show weaker "onion skin" behaviors than FF-type MUs. Our results offer an explanation for the longstanding dichotomy regarding MU firing patterns, shedding light on the factors influencing the firing-recruitment schemes.

4.
Vet Pathol ; : 3009858241249108, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38712876

ABSTRACT

Novel goose parvovirus (NGPV) is continuously threatening the global duck industry, as it causes short beak and dwarfism syndrome among different duck breeds. In this study, we investigated the viral pathogenesis in the tongue of affected ducks, as a new approach for deeper understanding of the syndrome. Seventy-three, 14- to 60-day-old commercial Pekin ducks were clinically examined. Thirty tissue pools of intestine and tongue (15 per tissue) were submitted for molecular identification. Clinical signs in the examined ducks were suggestive of parvovirus infection. All examined ducks had short beaks. Necrotic, swollen, and congested protruding tongues were recorded in adult ducks (37/73, 51%). Tongue protrusion without any marked congestion or swelling was observed in 20-day-old ducklings (13/73, 18%), and no tongue protrusion was observed in 15-day-old ducklings (23/73, 32%). Microscopically, the protruding tongues of adult ducks showed necrosis of the superficial epithelial layer with vacuolar degeneration. Glossitis was present in the nonprotruding tongues of young ducks, which was characterized by multifocal lymphoplasmacytic aggregates and edema in the propria submucosa. Immunohistochemical examination displayed parvovirus immunolabeling, mainly in the tongue propria submucosa. Based on polymerase chain reaction, goose parvovirus was detected in 9 out of 15 tongue sample pools (60%). Next-generation sequencing confirmed the presence of a variant goose parvovirus that is globally named NGPV and closely related to Chinese NGPV isolates. Novel insights are being gained from the study of NGPV pathogenesis in the tongue based on molecular and immunohistochemical identification.

5.
ACS Omega ; 9(12): 14198-14209, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38559915

ABSTRACT

In this work, a novel, green, and atom-efficient method for the synthesis of tetrahydro-ß-carboline derivatives using electrochemistry (EC) in deep eutectic solvents (DESs) was reported. The EC reaction conditions were optimized to achieve the highest yield. The experimental design was also optimized to perform the reaction in a two-step, one-pot reaction, thereby the time, workup procedure, and solvents needed were all reduced. The new approach achieved our strategy as EC served to decrease the time of reaction, eliminate the use of hazardous catalysts, and lower the energy required for the synthesis of the targeted compounds. On the other side, DESs were used as catalysts, in situ electrolytes, and noninflammable green solvents. The scope of the reaction was investigated using different aromatic aldehydes. Finally, the scalability of the reaction was investigated using a gram-scale reaction that afforded the product in an excellent yield.

7.
J Parasit Dis ; 48(1): 14-24, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38440749

ABSTRACT

Complications of parasite infections, especially kidney disease, have been linked to poorer outcomes. Acute kidney damage, glomerulonephritis, and tubular dysfunction are the most prevalent renal consequences of Parascaris equorum infection. The purpose of this study was to determine the pharmacological effects of green-produced zinc oxide nanoparticles (ZnO NPs) on P. equorum infection in male Wistar rats. Thirty-six male rats were divided into two groups of 18 each: infected and non-infected. Both groups were separated into three subgroups, each of which received distilled water, 30 mg/kg ZnO NPs, and 60 mg/kg ZnO NPs. After 10 days of ZnO NPs administration, four larvae per gram of kidney tissue were present in the untreated infected group. While, no larvae were present in ZnO NPs (30 mg/kg) treated group, and one larva/g.tissue was present in ZnO NPs (60 mg/kg) treated group compared to untreated infected animals. P. equorum infected rats had increased kidney biomarkers (creatinine, urea, uric acid), malondialdehyde, and nitric oxide, with a significant decrease in their antioxidant systems. On the other hand, infected treated rats with green-produced zinc oxide nanoparticles had a substantial drop in creatinine, urea, uric acid, malondialdehyde, and nitric oxide, as well as a significant rise in their antioxidant systems. P. equorum infection in rats caused severe degenerative and necrotic renal tissues. On the other hand, there were no detectable histopathological alterations in rats treated with ZnO NPs (30, 60 mg/kg) as compared to the infected untreated animals. When compared to infected untreated mice, immunohistochemical examination of nuclear factor-kappa B showed a significant decrease during treatment with ZnO NPs (30, 60 mg/kg). Green-produced zinc oxide nanoparticles are a viable therapeutic strategy for Parascaris equorum infection due to their potent anthelmintic activity, including a significant decrease in larval burden in infected treated rats.

8.
BMC Vet Res ; 20(1): 105, 2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38493097

ABSTRACT

The aim of this study was to examine the effects of salt addition on the skin gene expression of Mucin, Antimicrobial peptides, cortisol, and glucose in Oreochromis niloticus after 5-hour transportation in water. Three groups were compared: Control, post-transport without salt (PT-S), and post-transport with 5 g salt-1(PT + S), with a stocking density of 28.6 gL-1, 20 fish for each experimental group. The results showed that the PT-S group had more significant changes in gene expression than the PT + S group, suggesting that salt alleviated the stress and immune responses of O. niloticus. The PT-S group had higher expression of mucin- 2(MUC + 2) (7.58 folds) and mucin-5AC (MUC5-AC) (6.29 folds) than the PT + S group (3.30 folds and 4.16 folds, respectively). The PT-S group also had lower expression of ß-defensin-1 (Dß1) (0.42 folds), ß-defensin-2 (Dß2) (0.29 folds), and Cath1 (0.16 folds) than the PT + S group (0.82 folds, 0.69 folds, and 0.75 folds, respectively). The skin morphology of the PT-S group revealed some white patches with no goblet cell openings, while the PT + S group had better preservation of skin features with some goblet cell openings and slight white patches. This study indicates that O. niloticus can benefit from sodium chloride during transportation, as it helps to reduce stress and inflammation, balance mineral levels, enhance health and immunity, and regulate mucous secretion.


Subject(s)
Cichlids , Fish Diseases , beta-Defensins , Animals , Sodium Chloride , beta-Defensins/genetics , Water , Mucins , Animal Feed/analysis , Diet
9.
Int J Pharm ; 653: 123876, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38331331

ABSTRACT

Rheumatoid arthritis (RA) is a joint-destructive autoimmune disease that severely affects joint function. Despite the variability of treatment protocols, all of them are associated with severe side effects that compromise patient compliance. The main aim of the current study is to prepare localized effective RA treatment with reduced side effects by combining nanoencapsulation, photodynamic therapy (PDT) and hollow microneedles (Ho-MNs) to maximize the pharmacological effects of hypericin (HYP). To attain this, HYP-loaded emulsomes (EMLs) were prepared, characterized and administered through intradermal injection using AdminPen™ Ho-MNs combined with PDT in rats with an adjuvant-induced RA model. The prepared EMLs had a spherical shape and particle size was about 93.46 nm with an absolute entrapment efficiency. Moreover, confocal imaging indicated the interesting capability of Ho-MNs to deposit the HYP EMLs to a depth reaching 1560 µm into the subcutaneous tissue. In vivo, study results demonstrated that the group treated with HYP EMLs through Ho-MNs combined with PDT had no significant differences in joint diameter, TNF-α, IL1, HO-1, NRF2 and SD levels compared with the negative control group. Similarly, rats treated with the combination of HYP EMLs, Ho-MNs and PDT showed superior joint healing efficacy compared with the groups treated with HYP EMLs in dark, HYP ointment or HYP in microneedles in histopathological examination. These findings highlight the promising potential of photoactivated HYP EMLs when combined with Ho-MNs technology for RA management. The presented therapeutic EMLs-MNs platform could serve as a powerful game-changer in the development of future localized RA treatments.


Subject(s)
Arthritis, Rheumatoid , Perylene/analogs & derivatives , Photochemotherapy , Humans , Rats , Animals , Photochemotherapy/methods , Anthracenes , Arthritis, Rheumatoid/drug therapy , Photosensitizing Agents
10.
BMC Vet Res ; 20(1): 55, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38350905

ABSTRACT

Oreochromis niloticus (Nile tilapia) is a well-known economic fish species that can thrive under the right environmental circumstances. The transport of live fish, either for food or as companion animals, presents a big issue for animal welfare at the same time it is considered one of stressful conditions. Hence, the present study investigated the skin histopathological responses of O. niloticus that were attributed to stress and salt addition during transportation. Three experimental groups of O. niloticus the 1st is the control non-transported group (CG), the 2nd is transport in water without salt (PT-S) and the 3rd is transport in water containing 5gL- 1salt (PT + S), the last 2 groups were transported in 5 h transport model. Results indicate that the skin of PT-S fish showed a marked decrease in epidermal thickness, decreased number of goblet cells, and an increase in the sub-epidermal and dermal pigments with the presence of large edematous vacuoles. Fish skin from PT + S demonstrated mild hydropic swelling in epidermal cells with normal goblet (mucous) cells density, and more or less normal melanin pigment distribution in sub epidermis and on the dermis layers, however, dermis showed mild edematous spaces. Scanning microscopy of PT-S skin tissue showed few scratched white patches among normal regions that may represent a thickened surface with the decreased number of goblets cell opening, while the PT + S group showed moderate preservation of surface skin architectures with the presence of goblet (mucous) cells opening in spite of presence of slight thickened white patches. The estimated total lesion changes present in PT-S group showed a significant increase (P < 0.001) compared with the control (CG) group. On the other hand, PT + S showed significant (P < 0.001) improvement in the overall previously recorded changes compared with the PT-S group, and a non- significant change in the histological architectures compared with the control group. Our findings underlined the importance of skin and its mucous cover health during transportation. The use 5 gL- 1salt during O. niloticus transportation appears to preserve the surface skin features, and keep the goblet (mucous) cells open to the external surface, and may act as a deterrent for the release of mucus from goblet (mucous) cells in response to stress and lessen the stress of transportation.


Subject(s)
Cichlids , Fish Diseases , Animals , Skin/metabolism , Epidermis
11.
Calcif Tissue Int ; 114(1): 9-23, 2024 01.
Article in English | MEDLINE | ID: mdl-37603077

ABSTRACT

Weakness, one of the key characteristics of sarcopenia, is a significant risk factor for functional limitations and disability in older adults. It has long been suspected that reductions in motor unit firing rates (MUFRs) are one of the mechanistic causes of age-related weakness. However, prior work has not investigated the extent to which MUFR is associated with clinically meaningful weakness in older adults. Forty-three community-dwelling older adults (mean: 75.4 ± 7.4 years; 46.5% female) and 24 young adults (mean: 22.0 ± 1.8 years; 58.3% female) performed torque matching tasks at varying submaximal intensities with their non-dominant leg extensors. Decomposed surface electromyographic recordings were used to quantify MUFRs from the vastus lateralis muscle. Computational modeling was subsequently used to independently predict how slowed MUFRs would negatively impact strength in older adults. Bivariate correlations between MUFRs and indices of lean mass, voluntary activation, and physical function/mobility were also assessed in older adults. Weak older adults (n = 14) exhibited an approximate 1.5 and 3 Hz reduction in MUFR relative to non-weak older adults (n = 29) at 50% and 80% MVC, respectively. Older adults also exhibited an approximate 3 Hz reduction in MUFR relative to young adults at 80% MVC only. Our model predicted that a 3 Hz reduction in MUFR results in a strength decrement of 11-26%. Additionally, significant correlations were found between slower MUFRs and poorer neuromuscular quality, voluntary activation, chair rise time performance, and stair climb power (r's = 0.31 to 0.43). These findings provide evidence that slowed MUFRs are mechanistically linked with clinically meaningful leg extensor weakness in older adults.


Subject(s)
Frailty , Muscle, Skeletal , Young Adult , Humans , Female , Aged , Male , Muscle, Skeletal/physiology , Leg , Motor Neurons/physiology , Risk Factors , Muscle Strength/physiology
12.
Poult Sci ; 103(1): 103227, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38041891

ABSTRACT

The chicken business faces substantial economic losses due to the risk of parasitic coinfection. Because the current study aimed to investigate enteric parasitic coinfections problems among the suspected examined chicken farms, samples were collected during the field investigation from suspected freshly dead birds, clinically diseased, apparently healthy, and litter samples for further laboratory parasitological, histopathological, and immunological examinations. Variable mortalities with various clinical indicators, such as ruffled feathers, weight loss, diarrhea of various colors, and a decline in egg production, occurred on the farms under investigation. In addition, the treatment protocols of each of the farms that were evaluated were documented and the m-RNA levels of some cytokines and apoptotic genes among the infected poultry have been assessed. The prevalence rate of parasitic coinfection in the current study was found to be 8/120 (6.66%). Parasitological analysis of the samples revealed that they belonged to distinct species of Eimeria, cestodes, and Ascaridia galli. When deposited, A. galli eggs were nonembryonated and ellipsoidal, but cestodes eggs possessed a thin, translucent membrane that was subspherical. Eimeria spp. oocysts in layer chickens were identified as Eimeria acervulina and Eimeria maxima in broiler chickens. Our findings proved that coinfection significantly upregulated the IL-1ß, BAX, and Cas-3 genes. Conversely, the IL-10, BCL-2, and AKT mRNA levels were downregulated, indicating that nematode triggered apoptosis. The existence of parasite coinfection was verified by histological investigation of the various intestinal segments obtained from affected flocks. A. galli and cestodes obstructed the intestinal lumen, causing different histological alternations in the intestinal mucosa. Additionally, the lamina propria revealed different developmental stages of Eimeria spp. It was determined that parasite coinfection poses a significant risk to the poultry industry. It was recommended that stringent sanitary measures management methods, together with appropriate treatment and preventative procedures, be employed in order to resolve such issues.


Subject(s)
Coccidiosis , Coinfection , Eimeria , Parasites , Poultry Diseases , Animals , Coccidiosis/epidemiology , Coccidiosis/veterinary , Coccidiosis/parasitology , Chickens/parasitology , Coinfection/epidemiology , Coinfection/veterinary , Poultry Diseases/parasitology , Ovum , Eimeria/genetics
13.
Eur Heart J Suppl ; 25(Suppl H): H8-H12, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38046888

ABSTRACT

Pacemaker therapy is the cornerstone in treatment of bradycardia and conduction disorders. Several diagnostic tools are utilized to diagnose and guide the physicians for appropriate management and accordingly proper utilization of pacemaker therapy. The current article is discussing the different diagnostics used for appropriate evaluation and diagnosis of bradyarrhythmias and the suggested solutions to improve bradycardia diagnosis and pacemaker therapy utilization in underpenetrated areas.

14.
PeerJ ; 11: e16576, 2023.
Article in English | MEDLINE | ID: mdl-38089915

ABSTRACT

Background: Hemolytic anemia (HA) is a serious health condition resulting from reduced erythrocytes' average life span. Echinochrome (Ech) is a dark-red pigment found in shells and spines of sea urchins. Aim: Studying the potential therapeutic effect of Ech on phenylhydrazine (PHZ)-induced HA in rats. Methods: Eighteen rats were divided into three groups (n = 6): the control group, the phenylhydrazine-induced HA group and the Ech group, injected intraperitoneally with PHZ and supplemented with oral Ech daily for 6 days. Results: Ech resulted in a considerable increase in RBCs, WBCs, and platelets counts, hemoglobin, reduced glutathione, catalase, and glutathione-S-transferase levels, and a significant decrease in aspartate & alanine aminotransferases, alkaline phosphatase, gamma-glutamyl transferase, bilirubin, creatinine, urea, urate, malondialdehyde & nitric oxide levels in anemic rats. Histopathological examination of liver and kidney tissue samples showed marked improvement. Conclusion: Ech ameliorated phenylhydrazine-induced HA with a hepatorenal protective effect owing to its anti-inflammatory and antioxidant properties.


Subject(s)
Anemia, Hemolytic , Oxidative Stress , Rats , Animals , Antioxidants/pharmacology , Anemia, Hemolytic/chemically induced , gamma-Glutamyltransferase/pharmacology , Glutathione Transferase/adverse effects , Phenylhydrazines/adverse effects
15.
Acta Parasitol ; 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38057445

ABSTRACT

MAIN CONCLUSIONS: Green-synthesized zinc oxide nanoparticle is a promising treatment modality against parasitic infection through its powerful anthelmintic, antioxidant, healing promotion, and anti-inflammation effects. BACKGROUND: Nanoparticles have many properties, depending on their size, shape, and morphology, allowing them to interact with microorganisms, plants, and animals. OBJECTIVES: Investigation of the therapeutic effects of green-synthesized zinc oxide nanoparticles (ZnO NPs) on Parascaris equorum infection in rats. METHODS: Thirty-six rats were divided into two divisions: the first division is noninfected groups were allocated into three groups. Group 1: Control, group 2: ZnO NPs (30 mg/kg), and group 3: ZnO NPs (60 mg/kg). The second division is infected groups were allocated into three groups. Group 1: vehicle, group 2: ZnO NPs (30 mg/kg), and group 3: ZnO NPs (60 mg/kg). FINDINGS: Ten days post-infection, two larvae per gram of liver tissue were present in the vehicle group compared to the control group. No larvae were recovered from ZnO NPs (30 mg/kg), and one larva/g.tissue from ZnO NPs (60 mg/kg)-treated groups compared to untreated infected animals. Green-synthesized ZnO NPs caused a significant decrease in liver functions, low-density lipoprotein (LDL), cholesterol, triglycerides, malondialdehyde (MDA), and nitric oxide (NO). While it caused a significant increase in hemoglobin (HB), high-density lipoprotein (HDL), butyrylcholinesterase (BCHE), glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) in infected treated rats. The histological inflammation and fibroplasia scores showed a significant enhancement during the treatment with ZnO NPs (30, 60 mg/kg) compared to the infected untreated animals that scored the highest pathological destruction score. Immunohistochemical markers of NF-κB showed a significant decrease during the treatment with ZnO NPs (30, 60 mg/kg) compared to the infected untreated animals.

16.
PLoS One ; 18(12): e0294348, 2023.
Article in English | MEDLINE | ID: mdl-38064451

ABSTRACT

The study presents a meshless computational approach for simulating the three-dimensional multi-term time-fractional mobile-immobile diffusion equation in the Caputo sense. The methodology combines a stable Crank-Nicolson time-integration scheme with the definition of the Caputo derivative to discretize the problem in the temporal direction. The spatial function derivative is approximated using the inverse multiquadric radial basis function. The solution is approximated on a set of scattered or uniform nodes, resulting in a sparse and well-conditioned coefficient matrix. The study highlights the advantages of meshless method, particularly their simplicity of implementation in higher dimensions. To validate the accuracy and efficacy of the proposed method, we performed numerical simulations and compared them with analytical solutions for various test problems. These simulations were carried out on computational domains of both rectangular and non-rectangular shapes. The research highlights the potential of meshless techniques in solving complex diffusion problems and its successful applications in groundwater contamination and other relevant fields.


Subject(s)
Groundwater , Models, Theoretical , Water Movements , Solutions , Diffusion
17.
J Acoust Soc Am ; 154(6): 3943-3954, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38147018

ABSTRACT

Thermoacoustic refrigerators exploit the thermodynamic interaction between oscillating gas particles and a porous solid to generate a temperature gradient that provides a cooling effect. In this work, we present a resonator with dual enclosed driver end-caps and show that the temperature gradient across a ceramic thermoacoustic element placed in the cavity could be controlled by modifying the phase difference of the drivers, thus enabling precise control of the refrigeration capability via the temperature difference. Through deltaec simulation results, the response of the temperature gradient to various dynamic boundary conditions that alter the time-phasing and wave dynamics in the resonator are demonstrated. An experimental apparatus is constructed with two moving-coil speakers and a ceramic stack, which is shown to exhibit a temperature gradient along its length, based on the traveling-wave-like nature of the acoustic wave excited by the speakers. By adjusting the relative phase lag between the two speakers, the temperature gradient across the stack is made to increase, decrease, or flip sign. Finally, a desired temperature difference that changes in time is achieved. The results presented in this work represent a key conceptual advancement of thermoacoustic-based temperature control devices that can better serve in extreme environments and precision applications.

18.
Nanoscale ; 15(45): 18457-18472, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37941481

ABSTRACT

Clay nanoparticles, in particular synthetic smectites, have generated interest in the field of tissue engineering and regenerative medicine due to their utility as cross-linkers for polymers in biomaterial design and as protein release modifiers for growth factor delivery. In addition, recent studies have suggested a direct influence on the osteogenic differentiation of responsive stem and progenitor cell populations. Relatively little is known however about the mechanisms underlying nanoclay bioactivity and in particular the cellular processes involved in nanoclay-stem cell interactions. In this study we employed confocal microscopy, inductively coupled plasma mass spectrometry and transmission electron microscopy to track the interactions between clay nanoparticles and human bone marrow stromal cells (hBMSCs). In particular we studied nanoparticle cellular uptake mechanisms and uptake kinetics, intracellular trafficking pathways and the fate of endocytosed nanoclay. We found that nanoclay particles present on the cell surface as µm-sized aggregates, enter hBMSCs through clathrin-mediated endocytosis, and their uptake kinetics follow a linear increase with time during the first week of nanoclay addition. The endocytosed particles were observed within the endosomal/lysosomal compartments and we found evidence for both intracellular degradation of nanoclay and exocytosis as well as an increase in autophagosomal activity. Inhibitor studies indicated that endocytosis was required for nanoclay upregulation of alkaline phosphatase activity but a similar dependency was not observed for autophagy. This study into the nature of nanoclay-stem cell interactions, in particular the intracellular processing of nanosilicate, may provide insights into the mechanisms underlying nanoclay bioactivity and inform the successful utilisation of clay nanoparticles in biomaterial design.


Subject(s)
Mesenchymal Stem Cells , Nanoparticles , Humans , Osteogenesis , Clay , Tissue Engineering , Biocompatible Materials , Nanoparticles/chemistry
19.
Food Chem Toxicol ; 182: 114191, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37980978

ABSTRACT

This study investigated the effect of oral dosing of titanium dioxide nanoparticles (TNPs) and cadmium (Cd2+) on rat liver and the potential protective role of coenzyme Q10 (CQ10) against TNPs and Cd2+-induced hepatic injury. Seventy male Sprague Dawley rats were divided into seven groups and orally given distilled water, corn oil, CQ10 (10 mg/kg b.wt), TNPs (50 mg/kg b.wt), Cd2+ (5 mg/kg b.wt), TNPs + Cd2+, or TNPs + Cd2++CQ10 by gastric gavage for 60 successive days. The results showed that individual or mutual exposure to TNPs and Cd2+ significantly increased the serum levels of various hepatic enzymes and lipids, depleted the hepatic content of antioxidant enzymes, and increased malondialdehyde. Moreover, the hepatic titanium and Cd2+ content were increased considerably in TNPs and/or Cd2+-exposed rats. Furthermore, marked histopathological perturbations with increased immunoexpression of tumor necrosis factor-alpha and nuclear factor kappa B were evident in TNPs and/or Cd2+-exposed rats. However, CQ10 significantly counteracted the damaging effect of combined exposure of TNPs and Cd2+ on the liver. The study concluded that TNPs and Cd2+ exposure harm hepatic function and its architecture, particularly at their mutual exposure, but CQ10 could be a candidate protective agent against TNPs and Cd2+ hepatotoxic impacts.


Subject(s)
Nanoparticles , Tumor Necrosis Factor-alpha , Rats , Male , Animals , Tumor Necrosis Factor-alpha/metabolism , NF-kappa B/metabolism , Titanium/toxicity , Cadmium/toxicity , Cadmium/metabolism , Oxidative Stress , Rats, Sprague-Dawley , Antioxidants/pharmacology , Antioxidants/metabolism , Liver , Nanoparticles/toxicity
20.
CVIR Endovasc ; 6(1): 53, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37899370

ABSTRACT

BACKGROUND: Compared to conventional open surgery, minimally invasive catheter-based procedures have less post procedural complications. Transcatheter aortic valve implantation (TAVI) and endovascular aneurysm repair (EVAR) require large bore arterial access. Optimal site management of large bore arterial access is pivotal to reduce the hospital-acquired complications associated with large bore arterial access. We wanted to compare surgical cutdown versus percutaneous closure devices in site management of large bore arterial access. METHODS: Participants planned for TAVI or EVAR with large bore arterial access more than 10 French were included, while participants with history of bypass surgery, malignancies, thrombophilia, or sepsis were excluded. A consecutive sample of 100 participants (mean age 74.66 ± 2.65 years, 61% males) was selected, underwent TAVI or EVAR with surgical cutdown (group 1) versus TAVI or EVAR with Proglide™ percutaneous closure device (group 2). RESULTS: The incidence rate of hematoma was significantly lower in group 2 versus group 1 (p = 0.014), the mean procedure time (minutes) and the median hospital stay (days) were significantly higher in group 1 versus group 2 (t(98) = - 2.631, p = 0.01, and U = 2.403, p = 0.018, respectively), and the c-reactive protein pre-procedure and the c-reactive protein post-procedure were significantly lower in group 2 versus group 1 (U = -2.969, p = 0.003, and U = -2.674, p = 0.007, respectively). CONCLUSIONS: Our study showed a lower incidence rate of large bore arterial access complications as hematoma, a shorter procedure time, and a shorter hospital stay with percutaneous closure devices compared to surgical cutdown.

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