247 research outputs found

    Vascular mechanism of axonal degeneration in peripheral nerves in hemiplegic sides after cerebral hemorrhage: An experimental study

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    <p>Abstract</p> <p>Background</p> <p>Though retrograde neuronal death and vascular insufficiency have been well established in plegics following intracerebral hemorrhage, the effects of plegia on arterial nervorums of peripheral nerves have not been reported. In this study, the histopathological effects of the intracerebral hemorrhage on the dorsal root ganglions and sciatic nerves via affecting the arterial nervorums were investigated.</p> <p>Methods</p> <p>This study was conducted on 13 male hybrid rabbits. Three animals were taken as control group and did not undergo surgery. The remaining 10 subjects were anesthetized and were injected with 0.50 ml of autologous blood into their right sensory-motor region. All rabbits were followed-up for two months and then sacrificed. Endothelial cell numbers and volume values were estimated a three dimensionally created standardized arterial nervorums model of lumbar 3. Neuron numbers of dorsal root ganglions, and axon numbers in the lumbar 3 nerve root and volume values of arterial nervorums were examined histopathologically. The results were analyzed by using a Mann-Whitney-U test.</p> <p>Results</p> <p>Left hemiplegia developed in 8 animals. On the hemiplegic side, degenerative vascular changes and volume reduction in the arterial nervorums of the sciatic nerves, neuronal injury in the dorsal root ganglions, and axonal injury in the lumbar 3 were detected. Statistical analyses showed a significant correlation between the normal or nonplegic sides and plegic sides in terms of the neurodegeneration in the dorsal root ganglions (p < 0.005), axonal degeneration in the lumbar 3 nerve roots (p < 0.005), endothelial cell degeneration in the arterial nervorums (p < 0.001), and volume reduction in the arterial nervorums (p < 0.001).</p> <p>Conclusion</p> <p>Intracerebral hemorrhage resulted in neurodegeneration in the dorsal root ganglion and axonolysis in the sciatic nerves, endothelial injury, and volume reduction of the arterial nervorums in the sciatic nerves. The interruption of the neural network connection in the walls of the arterial nervorums in the sciatic nerves may be responsible for circulation disorders of the arterial nervorums, and arterial nervorums degeneration could result in sciatic nerves injury.</p

    Using covariates for improving the minimum redundancy maximum relevance feature selection method

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    Maximizing the joint dependency with a minimum size of variables is generally the main task of feature selection. For obtaining a minimal subset, while trying to maximize the joint dependency with the target variable, the redundancy among selected variables must be reduced to a minimum. In this paper, we propose a method based on recently popular minimum Redundancy-Maximum Relevance (mRMR) criterion. The experimental results show that instead of feeding the features themselves into mRMR, feeding the covariates improves the feature selection capability and provides more expressive variable subsets

    Antioxidant enzymes and lipid peroxidation in adolescents with inhalant abuse

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    Glue and thinner sniffing is a serious medical problem since the volatile constituents of these substances can lead to severe damage to bone marrow, liver, kidney, brain, and heart. The exact mechanisms responsible for tissue and organ damage in children with inhalant abuse have not yet been determined. In this study, we aimed to determine the levels of antioxidant enzymes and malondialdehyde in children with inhalant abuse. Erythrocyte and plasma glutathione peroxidase (GSH-Px) activities, erythrocyte superoxide dismutase (SOD) activity, and erythrocyte and plasma malondialdehyde (MDA) levels were measured as biological markers of oxidative damage and lipid peroxidation in 37 glue and thinner (inhalant) abusers. The levels were compared with those of the 27 well-matched healthy adolescents. Erythrocyte SOD activity and erythrocyte and plasma MDA levels were significantly higher, whereas erythrocyte and plasma GSH-Px activities were significantly lower in children with inhalant abuse when compared to controls (

    Štetni učinci pušenja tijekom trudnoće na DNA i razine reaktivnih oblika kisika (ROS) u krvi majke i novorođenčeta

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    Some of the genotoxic/carcinogenic substances or metabolites in cigarette smoke are capable of passing through the placenta and harming a newborn’s health. Smoking is also known as a factor in the formation of oxidative damage and the main mechanism involved in the carcinogenic process. Predetermining this genotoxic risk can be successfully achieved by measuring certain parameters of oxidative stress. The comet assay is considered an important biomarker for the evaluation of genotoxic substances and is effective for detecting DNA damage caused by smoking. This study examined third trimester bloods and the cord blood of 28 actively smoking and 22 non-smoking mothers in terms of DNA damage and oxidative stress parameters. Cu/Zn superoxide dismutase (CuZn-SOD), malondialdehyde (MDA), catalase (CAT), plasma nitrite/nitrates (NO2•/NO3•), selenium-dependent glutathione peroxidase (Se-GPx), Cu, and Zn levels were measured as indicators of oxidative damage. There were no significant increases in DNA damage of the actively smoking pregnant group in comparison with the non-smoking pregnant group, either in the third trimester or cord blood. Oxidative stress parameters of smoker and non-smoker groups were statistically different for MDA (p<0.05), CuZn-SOD (p<0.01), Se-GPx (p<0.05) values while the difference was not significant for NO2•/NO3•, CAT, Zn, and Cu values. The same values were also investigated in cord blood, and only NO2•/NO3• (p<0.01), Se-GPx (p<0.01 and CAT (p<0.001) values were found statistically different. Smoking mothers may have been exposed to more oxidative stress than non-smoking mothers.Pojedine genotoksične/kancerogene supstancije ili metaboliti u cigaretnom dimu mogu proći kroz posteljicu i naštetiti zdravlju novorođenčeta. Pušenje je također poznato kao čimbenik pri nastanku oksidacijskog oštećenja DNA i u procesu kancerogeneze. Ovaj genotoksični rizik može se uspješno odrediti mjerenjem određenih parametara oksidacijskog stresa. Komet-test smatra se važnim biološkim biljegom pri evaluaciji genotoksičnih supstancija i iznimno učinkovitim sredstvom pronalaženja oštećenja DNA uzrokovanih pušenjem. Ova studija proučava krv trudnica u trećem tromjesečju trudnoće i fetalnu krv 28 majki aktivnih pušačica te 22-ju majki nepušačica vezano za oksidacijska oštećenja DNA i parametre oksidacijskog stresa. Razine Cu/Zn superoksidne dismutaze (CuZn-SOD), malondialdehida (MDA), katalaze (CAT), nitrita/nitrata u plazmi (NO2-/NO3-), selenijeve glutation peroksidaze (Se-GPx), Cu i Zn mjerene su kao pokazatelji oksidacijskog oštećenja. Nije bilo značajnih povećanja oštećenja DNA u skupini trudnica aktivnih pušačica u usporedbi sa skupinom trudnica nepušačica, ni u krvi iz trećeg tromjesečja ni u fetalnoj krvi. Parametri oksidacijskog stresa pušačke i nepušačke skupine bili su statistički različiti za vrijednosti MDA (p<0,05), CuZn-SOD (p<0,01), Se-GPx (P<0,05), dok razlika nije bila značajna za vrijednosti NO2-/NO3-, CAT, Zn i Cu. Iste su vrijednosti ispitane i u fetalnoj krvi, a jedino su vrijednosti NO2-/NO3- (p<0,01), Se-GPx (p<0,01) i CAT (p<0,001) bile statistički različite. Vjerojatno je da su majke pušačice bile izložene većem oksidacijskom stresu od majki nepušačica

    Utjecaj desflurana i sevoflurana na razine oksidativnog stresa u tkivima štakora

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    General anaesthetics are often used in patients who are under oxidative stress due to a critical illness or surgical trauma. Some anaesthetics may worsen oxidative stress and some may act as antioxidants. The aim of this study was to evaluate liver, brain, kidney, and lung tissue oxidative stress in rats exposed to desflurane and sevoflurane and in unexposed rats. The animals were divided in three groups: control (received only air); sevoflurane (8 %), and desflurane (4 %). After four hours of exposure, we evaluated the levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), Cu, and Zn. Exposure to either of the anaesthetics significantly increased lung MDA levels compared to control (Mann-Whitney U test; P<0.05), probably because it is the tissue directly exposed to anaesthetic gases. Oxidative stress and antioxidant activity in other tissues varied between the desflurane and sevoflurane groups. Our results suggest that anaesthesiologist should not only be aware of the oxidative or antioxidative potential of anaesthetics they use, but should also base their choices on organs which are the most affected by their oxidative actionkisikovih radikala tako i zbog smanjene aktivnosti obrambenih sustava koji se mogu oduprijeti njihovu djelovanju. Stoga su saznanja o antioksidativnom kapacitetu anestetika koji se primjenjuju prije nekoga kirurškog zahvata vrlo važna i od velikog su kliničkog značenja. Sevofl uran i desfl uran su inhalacijski anestetici koji se učestalo rabe u svrhu uvođenja bolesnika u anesteziju. Cilj ovog istraživanja bio je utvrditi razine oksidativnog stresa u različitim tkivima štakora i usporediti razlike u odgovoru tkiva na izlaganje navedenim anesteticima. U tu svrhu razine oksidativnog stresa izmjerili smo u jetri, mozgu, bubrezima i plućima štakora podijeljenih u tri eksperimentalne skupine. Kontrolna skupina udisala je samo zrak, dok su druge dvije skupine izložene 8 %-tnomu sevofl uranu te 4 %-tnomu desfl uranu tijekom 4 h. Nakon završetka obrade životinje su žrtvovane i uzimani su im uzorci tkiva za biokemijske analize. Mjerena je razina malondialdehida (MDA), aktivnst enzima superoksid dismutaze (SOD) i glutation peroksidaze (GSH-Px) te razine bakra i cinka. Izloženost anesteticima izazvala je oksidativni stres u plućima, na što upućuje značajno povišena razina MDA (Mann-Whitney U-test P<0.05) izmjerena u plućnom tkivu štakora obiju izloženih skupina u odnosu na kontrolu. Plućno je tkivo u odnosu na ostala tkiva podložnije štetnim utjecajima reaktivnih kisikovih radikala vjerojatno stoga što je ono prvo izloženo plinovitim anesteticima nakon njihova ulaska u organizam. Razine oksidativnog stresa i antioksidativne aktivnosti koje smo izmjerili u ostalim tkivima bile su različite te su ovisile o primijenjenom anestetiku. Na osnovi dobivenih rezultata možemo zaključiti da bi se zbog različitog odgovora tkiva izbor anestetika trebao provoditi na individualnoj osnovi

    Mapping artificial intelligence adoption in hepatology practice and research: challenges and opportunities in MENA region

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    BackgroundArtificial intelligence (AI) is increasingly relevant to hepatology, yet real-world adoption in the Middle East and North Africa (MENA) is uncertain. We assessed awareness, use, perceived value, barriers, and policy priorities among hepatology clinicians in the region.MethodsA cross-sectional online survey targeted hepatologists and gastroenterologists across 17 MENA countries. The survey assessed clinical and research applications of AI, perceived benefits, clinical and research use, barriers, ethical considerations, and institutional readiness. Descriptive statistics and thematic analysis were performed.ResultsOf 285 invited professionals, 236 completed the survey (response rate: 82.8%). While 73.2% recognized the transformative potential of AI, only 14.4% used AI tools daily, primarily for imaging analysis and disease prediction. AI tools were used in research by 39.8% of respondents, mainly for data analysis, manuscript writing assistance, and predictive modeling. Major barriers included inadequate training (60.6%), limited AI tool access (53%), and insufficient infrastructure (53%). Ethical concerns focused on data privacy, diagnostic accuracy, and over-reliance on automation. Despite these challenges, 70.3% expressed strong interest in AI training., and 43.6% anticipating routine clinical integration within 1–3 years.ConclusionMENA hepatologists are optimistic about AI but report limited routine use and substantial readiness gaps. Priorities include scalable training, interoperable infrastructure and standards, clear governance with human-in-the-loop safeguards, and region-specific validation to enable safe, equitable implementation
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