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21.
SARS-CoV-2 is a type of Betacoronaviruses responsible for COVID-19 pandemic disease, with more than 1.745 million fatalities globally as of December-2020. Genetically, it is considered the second largest genome of all RNA viruses with a 5′ cap and 3′ poly-A tail. Phylogenetic analyses of coronaviruses reveal that SARS-CoV-2 is genetically closely related to the Bat-SARS Like-Corona virus (Bat-SL-Cov) with 96% whole-genome identity. SARS-CoV-2 genome consists of 15 ORFs coded into 29 proteins. At the 5′ terminal of the genome, we have ORF1ab and ORF1a, which encode the 1ab and 1a polypeptides that are proteolytically cleaved into 16 different nonstructural proteins (NSPs). The 3′ terminal of the genome represents four structural (spike, envelope, matrix, and nucleocapsid) and nine accessory (3a, 3b, 6, 7a, 7b, 8b, 9a, 9b, and orf10) proteins. As the number of COVID-19 patients increases dramatically worldwide, there is an urgent need to find a quick and sensitive diagnostic tool for controlling the outbreak of SARS-CoV-2 in the community. Today, molecular testing methods utilizing viral genetic material (e.g., PCR) represent the crucial diagnostic tool for the SARS-CoV-2 virus despite its low sensitivity in the early stage of viral infection. This review summarizes the genome composition and genetic characterization of the SARS-CoV-2.  相似文献   
22.
BACKGROUND: Although nonmammary tumors metastatic to the breast are relatively uncommon, a correct diagnosis is essential to appropriate management. Radiologically these lesions are single, round, discrete lesions without the spiculations of primary malignancies. Fine needle aspiration biopsy (FNAB) may provide a definitive diagnosis, thereby sparing patients unnecessary surgery. CASES: Seventeen cases of nonmammary malignancies diagnosed by fine needle aspiration of the breast were identified in the cytopathology files at three different institutions from 1989 to 1999. Three of the cases are of particular interest, including a mucoepidermoid carcinoma of salivary gland origin and a small cell undifferentiated carcinoma of rectal origin, neither of which has been reported in the literature previously. The third case was a male with a breast mass that was originally thought to be primary based on clinical, cytologic and immunocytochemical features but subsequently was determined to be a metastasis from the lung. CONCLUSION: Virtually any malignancy may metastasize to the breast. FNAB is the best approach to the diagnosis of tumors that either clinically or radiographically are not typical of primary breast tumors. Extramammary neoplasms metastatic to the breast may be definitively diagnosed by FNAB, resulting in the most appropriate as well as cost-effective patient management.  相似文献   
23.
Novel photoluminescent nanocomposite sheets were prepared for simple commercial manufacturing of transparent and luminous photochromic smart windows. A simple physical integration of lanthanide-doped strontium aluminium oxide (LdSAO) nanoparticles into recycled polyethylene (PE) waste produced a smart nanocomposite with persistent phosphorescence and photochromic properties. Because the nanoparticle form of LdSAO is important for developing transparent materials, LdSAO nanoparticles were well dispersed in the PE matrix. Both the morphologies and chemical compositions of the LdSAO nanoparticles and LdSAO-containing luminescent PE sheets were investigated. Both LdSAO-free and photoluminescent PE sheets were colourless in normal daylight. However the LdSAO-containing PE luminescent samples only exhibited a brilliant green colour under ultraviolet (UV) light and a greenish-yellow colour in the dark as verified by Commission Internationale de l'éclairage laboratory parameters. Both absorbance and emission bands were monitored at 377 and 436/517 nm, respectively. The LdSAO-containing PE luminescent sheets were compared with the LdSAO-free sample using both photoluminescence spectroscopy and for their mechanical properties and were found to have improved scratch resistance, UV protection, and superhydrophobic activity. Due to the added LdSAO, photoluminescence, decay, and lifetime spectral tests confirmed its photochromic fluorescence and long-lasting phosphorescence characteristics. The PE@LdSAO nanocomposite sheets displayed UV protection, photostability, hydrophobicity, and excellent durability compared with the blank LdSAO-free PE sheet.  相似文献   
24.
Despite intensive efforts, there is no effective remedy for COVID‐19. Moreover, vaccination efficacy declines over time and may be compromised against new SARS‐CoV‐2 lineages. Therefore, there remains an unmet need for simple, accessible, low‐cost and effective pharmacological anti‐SARS‐CoV‐2 agents. ArtemiC is a medical product comprising artemisinin, curcumin, frankincense and vitamin C, all of which possess anti‐inflammatory and anti‐oxidant properties. The present Phase II placebo‐controlled, double‐blinded, multi‐centred, prospective study evaluated the efficacy and safety of ArtemiC in patients with COVID‐19. The study included 50 hospitalized symptomatic COVID‐19 patients randomized (2:1) to receive ArtemiC or placebo oral spray, twice daily on Days 1 and 2, beside standard care. A physical examination was performed, and vital signs and blood tests were monitored daily until hospital discharge (or Day 15). A PCR assessment of SARS‐CoV‐2 carriage was performed at screening and on last visit. ArtemiC improved NEWS2 in 91% of patients and shortened durations of abnormal SpO2 levels, oxygen supplementation and fever. No treatment‐related adverse events were reported. These findings suggest that ArtemiC curbed deterioration, possibly by limiting cytokine storm of COVID‐19, thus bearing great promise for COVID‐19 patients, particularly those with comorbidities.  相似文献   
25.
Dihydropyrimidine dehydrogenase (DPD) deficiency is an autosomal recessive disorder that shows large phenotypical variability, ranging from no symptoms to intellectual disability, motor retardation, and convulsions. In addition, homozygous and heterozygous mutation carriers can develop severe 5-fluorouracil (5-FU) toxicity. The lack of genotype-phenotype correlation and the possibility of other factors playing a role in the manifestation of the neurological abnormalities, make the management and education of asymptomatic DPD individuals more challenging. We describe a 3-month-old baby who was incidentally found by urine organic acid testing (done as part of positive newborn screen) to have very high level of thymine and uracil, consistent with DPD deficiency. Since the prevalence of asymptomatic DPD deficiency in the general population is fairly significant (1 in 10,000), we emphasize in this case study the importance of developing a guideline in genetic counseling and patient education for this condition as well as other incidental laboratory findings.  相似文献   
26.
Photodynamic therapy (PDT) is a clinically approved procedure for targeting tumor cells. Though several different photosensitizers have been developed, there is still much demand for novel photosensitizers with improved properties. In this study we aim to characterize the accumulation, localization and dark cytotoxicity of the novel photosensitizers developed in‐house derivatives of porphyrazines ( pz I‐IV) in primary murine neuronal cells, as well as to identify the concentrations at which pz still effectively induces death in glioma cells yet is nontoxic to nontransformed cells. The study shows that incubation of primary neuronal and glioma cells with pz I‐IV leads to their accumulation in both types of cells, but their rates of internalization, subcellular localization and dark toxicity differ significantly. Pz II was the most promising photosensitizer. It efficiently killed glioma cells while remaining nontoxic to primary neuronal cells. This opens up the possibility of evaluating pz II for experimental PDT for glioma.   相似文献   
27.
Patient protection has become one of the key elements of the quality of health care systems in Saudi Arabia. Medical errors that threaten patient safety are mediated by several factors including system risk factors. Hence, we used a self-structured questionnaire to assess and rank the system factors according to the perceptions of nurses working in the hospitals of the ministry of health in Hail, KSA. Eight out of twelve factors tested were perceived as threatening factors of the patient safety that are; ''Shortage of medical staff'', ''Poor design of the hospital structure'', ''Long working hours'', ''Overcrowding of patients'',''Poor coordination between hospital departments, ''Punitive and blaming environment, ''Lack of clinical practice standards'' and, ''Poor financial incentives''. Thus, considering the negative impact of the identified threatening system factors in this study on patient safety, urgent planning and managing appropriate corrective actions should be designed to improve patient safety issues.  相似文献   
28.
Neurochemical Research - Astrocytes are the primary homeostatic cells of the central nervous system, essential for normal neuronal development and function, metabolism and response to injury and...  相似文献   
29.
The exact pathophysiology of non-alcoholic steatohepatitis (NASH) is not known. Previous studies suggest that dietary advanced glycation end products (AGEs) can cause oxidative stress in liver. We aim to study the effects of dietary AGEs on liver health and their possible role in the pathogenesis of NASH. METHODS: Two groups of mice were fed the same diet except the AGE content varied. One group was fed a high AGE diet and the second group was fed a regular AGE diet. Liver histology, alanine aminotransferase, aspartate aminotransferase, fasting glucose, fasting insulin, insulin resistance and glucose tolerance were assessed. RESULTS: Histology revealed that neutrophil infiltration occurred in the livers of the high AGE group at week 26; steatosis did not accompany liver inflammation. At week 39 livers from both groups exhibited macro- or micro-steatosis, yet no inflammation was detected. Higher insulin levels were detected in the regular AGE group at week 26 (P = 0.034), compared to the high AGE group. At week 39, the regular AGE group showed higher levels of alanine aminotransferase (P<0.01) and aspartate aminotransferase (P = 0.02) than those of the high AGE group. CONCLUSIONS: We demonstrate that a high AGE diet can cause liver inflammation in the absence of steatosis. Our results show that dietary AGEs could play a role in initiating liver inflammation contributing to the disease progression of NASH. Our observation that the inflammation caused by high AGE alone did not persist suggests interesting future directions to investigate how AGEs contribute to pro-oxidative and anti-oxidative pathways in the liver.  相似文献   
30.
Plant extracts and essential oils have been widely studied and used as antimicrobial agents in the last decades. In our study we investigated the antimicrobial activities of Olbas(?) Tropfen (in the following named Olbas), a traditionally used complex essential oil distillate, in comparison to its individual essential oil ingredients. Olbas (10g) consists of three major components such as peppermint oil (5.3g), eucalyptus oil (2.1g), and cajuput oil (2.1g) and of two minor constituents like juniper berry oil (0.3g) and wintergreen oil (0.2g). The composition of Olbas and the five individual essential oils were characterized by GLC-MS. According to GLC-MS analysis 1,8-cineol is the main component of the complex essential oil distillate followed by menthol and menthone. The minimum inhibitory and minimum microbicidal concentrations of Olbas and each of the single essential oils were evaluated in 17 species/strains of bacteria and fungi. Time-kill assay was performed to compare the microbicidal activity of Olbas and peppermint oil during several time intervals. Olbas displayed a high antimicrobial activity against all test strains used in this study, among them antibiotic resistant MRSA (methicillin-resistant Staphylococcus aureus) and VRE (vancomycin-resistant Enterococcus). Its antimicrobial activity was comparable to that of peppermint oil which was the most potent one of all individual essential oils tested. In the time kill assay Olbas as well as peppermint oil demonstrated similar microbicidal activities. Based on its wide antimicrobial properties Olbas can be a useful agent for the treatment of uncomplicated infections of skin and respiratory tract.  相似文献   
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