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1.
Mar Pollut Bull ; 194(Pt B): 115367, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37567130

RESUMO

The objective of this study is to assess the natural resources and radiological risks of Wadi El Gemal Island by examining its topography, mineralogy, geochemistry, and radioactive distributions. This island, which is situated at the outlet of Wadi El Gemal in Egypt's southeastern Desert, has a unique shape resembling a dolphin based on Landsat imagery. It's a part of the Wadi El Gemal-Hamata Protectorate and is notable for its diverse environmental, geological, economic, and archeological features, including recent reefs, sandy deposits, Quaternary carbonate sediments, and mangroves. The main natural resources on the island are fauna, mangrove forests, and flora. Samples collected from the island were analyzed using a NaI detector to measure the concentrations of radionuclides such as 238U, 232Th, 226Ra, and 40K, which were found to be within acceptable levels according to UNSCAR guidelines. The radionuclide 238U, 232Th, 226Ra, and 40K activity concentrations of the collected samples were 32.55 ± 9, 12.63 ± 4, 12.49 ± 4, and 325 ± 34 Bq/kg, respectively. Regarding radiological hazard indices, the values of absorbed gamma dose rate (36.06 ± 5.42 nGy/h), radium equivalent activity (73.88 ± 14.4 Bq/kg), annual effective dose indoor (0.18 ± 0.03 mSv/y) and outdoor (0.04 ± 0.01 mSv/y), internal (0.29 ± 0.05) and external (0.2 ± 0.03) indices, and excess lifetime cancer index (0.15 ± 0.05 × 10-3).This is suggest that there is no significant risk associated with these sediments.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Radioisótopos/análise , Rádio (Elemento)/análise , Recursos Naturais , Tório/análise , Poluentes Radioativos do Solo/análise , Radioisótopos de Potássio/análise , Espectrometria gama
2.
Sci Rep ; 13(1): 11497, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37460601

RESUMO

Emerald and other beryls represent a family of the most valuable gemstone around the world and particularly in Egypt. Beryllium (Be) contents in beryl-bearing bedrocks in south Sinai (Wadi Ghazala and Wadi Sedri), and in central and south Eastern Desert of Egypt (Igla area, Zabara-Um Addebaa belt, Homret Akarem, and Homret Mukpid) were investigated in this study. The environmental risk levels of Be, associated major ions, and heavy metals in groundwater nearby to beryl-bearing mineralization were also evaluated. Results showed that Be contents ranged from 1 to 374 ppm in beryl-bearing bedrocks, while in nearby groundwater, Be content has a range of 0.0001-0.00044 mg/L with an average of 0.00032 mg/L, which is within the permissible levels and below (0.004) the U.S. EPA maximum contaminant level (MCL). Most levels of heavy metals (e.g., Be, B, Ni, V, Fe, and Al) in the investigated groundwater of central and south Eastern Desert and south Sinai are within the permissible levels and below their corresponding U.S. EPA MCLs. This study also investigated the radiological risk of natural radionuclides distributed in beryl-bearing bedrocks in the study area using gamma spectrometry; Sodium Iodide [NaI(Tl)] scintillation detector. Among the estimated mean 238U, 232Th, and 226Ra activity concentrations of the studied beryl-bearing rocks, Homret Mukpid (79, 87.15, 60.26 Bq kg-1) and Homret Akarem (111.6, 51.17, 85.1 Bq kg-1) contain the highest values. This may be attributed to their highly fractionated granitic rocks that host uranium and thorium reservoir minerals such as zircon, allanite, and monazite. The estimated data of multi-radiological parameters such as absorbed gamma dose, outdoor and indoor annual effective dose, radium equivalent activity, internal and external indices, index of excess cancer, and effective dose to human organs reflecting no significant impacts from the emitted natural gamma radiation.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36078432

RESUMO

The current contribution goal is to measure the distribution of the radionuclide within the exposed rock units of southwestern Sinai, Seih-Sidri area, and assess the radiological risk. Gneisses, older granites, younger gabbro, younger granites, and post granitic dikes (pegmatites) are the main rock units copout in the target area. Radioactivity, as well as radiological implications, were investigated for forty-three samples from gneisses (seven hornblende biotite gneiss and seven biotite gneiss), older granites (fourteen samples), and younger granites (fifteen samples of syenogranites) using NaI (Tl) scintillation detector. External and internal hazard index (Hex, Hin), internal and external level indices (Iα, Iγ), absorbed dose rates in the air (D), the annual effective dose equivalent (AED), radium equivalent activity (Raeq), annual gonadal dose (AGDE), excess lifetime cancer risk (ELCR), and the value of Upper Continental Core 232Th/238U mass fractions were determined from the obtained values of 238U, 232Th and 40K for the examined rocks of Seih-Sidri area. The average 238U mg/kg in hornblende biotite gneiss and biotite gneiss, older granites, and syenogranites is 2.3, 2.1, 2.7, and 8.4 mg/kg, respectively, reflecting a relatively higher concentration of uranium content in syenogranites. The results suggest that using these materials may pose risks to one's radiological health.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Urânio , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Radioisótopos/análise , Saúde Radiológica , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise
4.
Br J Radiol ; 94(1117): 20200812, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33305996

RESUMO

An outbreak of corona virus disease 2019 (COVID-19) began in China in December 2019, and rapidly spread to become a worldwide pandemic. Neurological complications encountered in hospitalized patients include acute arterial ischemic cerebrovascular stroke, cerebral venous thrombosis, critical illness-associated cerebral microbleeds, hypertensive hemorrhagic posterior reversible encephalopathy, meningoencephalitis/flare up of infections, flare up of multiple sclerosis, acute disseminated encephalomyelitis, cerebral hemodynamic/hypoxic changes such as watershed ischemic changes and hypoxic ischemic encephalopathy, and spine manifestations of Guillain Barre syndrome and viral myelitis. The purpose of our study is to illustrate the different neuroimaging features in critically ill hospitalized COVID-19 positive patients in the State of Qatar.


Assuntos
COVID-19/complicações , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/etiologia , Neuroimagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Case Rep Oncol ; 13(2): 569-577, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547383

RESUMO

Coronavirus disease-19 is a respiratory viral disease that commonly presents with mild symptoms. However, it can cause serious complications such as acute respiratory disease, especially in patients with comorbidities. As it is a new disease, the full picture of the disease and its complications are not yet fully understood. Moreover, the patients at risk of complications are not well identified; and the data about the risk in patients with hematological malignancies is limited. Here, we report a 65-year-old male with accelerated phase chronic myeloid leukemia, on dasatinib, tested positive for coronavirus disease-19, then complicated with febrile neutropenia acute respiratory distress syndrome.

6.
Curr Diabetes Rev ; 15(4): 340-345, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30813879

RESUMO

Diabetic polyneuropathy (DPN) is a complex and multifactorial entity in which various factors besides hyperglycemia play an important role. Symptoms of DPN are sensory, motor or autonomic. Intensive research proved that oxidative stress is the common denominator for the four major destructive pathways of hyperglycemia including increased hexosamine pathway flux, activation of Protein kinase-C (PKC) pathway, increased Advanced Glycated End-products (AGEs) formation, and increased Polyol Pathway flux. National data in Egypt confirms that more than 60% of Egyptian diabetic patients suffer from neuropathy. The most common complications of DPN are Cardiac Autonomic Neuropathy (CAN), diabetic foot and ulcers, neuromuscular disability, and anxiety. In addition, DPN affects the Quality of Life (QoL). According to common clinical practice, the common diagnostic tools are bed-side diagnosis and electrophysiological tests. Early diagnosis is critical to improve the prognosis of DPN and therapeutic intervention in the early phase. In this review, we provide a clear understanding of the pathogenesis, early diagnosis and the good management of DPN. Since the pathogenesis of DPN is multifactorial, its management is based on combination therapy of symptomatic; either pharmacological or non-pharmacological treatments, and pathogenic treatment. Alpha Lipoic Acid (ALA) is a potent anti-oxidant that has several advantages as a pathogenic treatment of DPN. So, in clinical practice, ALA may be prescribed for patients with early neuropathic deficits and symptoms. Patient education has an important role in the managemement of DPN.


Assuntos
Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/patologia , Neuropatias Diabéticas/terapia , Consenso , Egito , Humanos , Qualidade de Vida
7.
J Pathol ; 237(4): 482-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26213100

RESUMO

The low molecular weight protein tyrosine phosphatase (LMPTP), encoded by the ACP1 gene, is a ubiquitously expressed phosphatase whose in vivo function in the heart and in cardiac diseases remains unknown. To investigate the in vivo role of LMPTP in cardiac function, we generated mice with genetic inactivation of the Acp1 locus and studied their response to long-term pressure overload. Acp1(-/-) mice develop normally and ageing mice do not show pathology in major tissues under basal conditions. However, Acp1(-/-) mice are strikingly resistant to pressure overload hypertrophy and heart failure. Lmptp expression is high in the embryonic mouse heart, decreased in the postnatal stage, and increased in the adult mouse failing heart. We also show that LMPTP expression increases in end-stage heart failure in humans. Consistent with their protected phenotype, Acp1(-/-) mice subjected to pressure overload hypertrophy have attenuated fibrosis and decreased expression of fibrotic genes. Transcriptional profiling and analysis of molecular signalling show that the resistance of Acp1(-/-) mice to pathological cardiac stress correlates with marginal re-expression of fetal cardiac genes, increased insulin receptor beta phosphorylation, as well as PKA and ephrin receptor expression, and inactivation of the CaMKIIδ pathway. Our data show that ablation of Lmptp inhibits pathological cardiac remodelling and suggest that inhibition of LMPTP may be of therapeutic relevance for the treatment of human heart failure.


Assuntos
Insuficiência Cardíaca/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Cardiomiopatia de Takotsubo/metabolismo , Animais , Modelos Animais de Doenças , Imunofluorescência , Humanos , Immunoblotting , Imunoprecipitação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Ratos
8.
J Pathol ; 235(4): 606-18, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25421395

RESUMO

Heart failure is associated with the reactivation of a fetal cardiac gene programme that has become a hallmark of cardiac hypertrophy and maladaptive ventricular remodelling, yet the mechanisms that regulate this transcriptional reprogramming are not fully understood. Using mice with genetic ablation of calcium/calmodulin-dependent protein kinase II δ (CaMKIIδ), which are resistant to pathological cardiac stress, we show that CaMKIIδ regulates the phosphorylation of histone H3 at serine-10 during pressure overload hypertrophy. H3 S10 phosphorylation is strongly increased in the adult mouse heart in the early phase of cardiac hypertrophy and remains detectable during cardiac decompensation. This response correlates with up-regulation of CaMKIIδ and increased expression of transcriptional drivers of pathological cardiac hypertrophy and of fetal cardiac genes. Similar changes are detected in patients with end-stage heart failure, where CaMKIIδ specifically interacts with phospho-H3. Robust H3 phosphorylation is detected in both adult ventricular myocytes and in non-cardiac cells in the stressed myocardium, and these signals are abolished in CaMKIIδ-deficient mice after pressure overload. Mechanistically, fetal cardiac genes are activated by increased recruitment of CaMKIIδ and enhanced H3 phosphorylation at hypertrophic promoter regions, both in mice and in human failing hearts, and this response is blunted in CaMKIIδ-deficient mice under stress. We also document that the chaperone protein 14-3-3 binds phosphorylated H3 in response to stress, allowing proper elongation of fetal cardiac genes by RNA polymerase II (RNAPII), as well as elongation of transcription factors regulating cardiac hypertrophy. These processes are impaired in CaMKIIδ-KO mice after pathological stress. The findings reveal a novel in vivo function of CaMKIIδ in regulating H3 phosphorylation and suggest a novel epigenetic mechanism by which CaMKIIδ controls cardiac hypertrophy.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomegalia/enzimologia , Insuficiência Cardíaca/enzimologia , Hemodinâmica , Histonas/metabolismo , Miócitos Cardíacos/enzimologia , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Animais , Sítios de Ligação , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/deficiência , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Cardiomegalia/genética , Cardiomegalia/fisiopatologia , Cardiomegalia/prevenção & controle , Células Cultivadas , Montagem e Desmontagem da Cromatina , Modelos Animais de Doenças , Epigênese Genética , Regulação Enzimológica da Expressão Gênica , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/prevenção & controle , Humanos , Masculino , Camundongos Knockout , Fosforilação , Processamento de Proteína Pós-Traducional , Interferência de RNA , RNA Polimerase II/metabolismo , Ratos , Transcrição Gênica , Transfecção
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