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Muhammad Arsalan Raffat Naila Irum Hadi Mervyn Hosein Adnan Mustafa Zubairi Sana Ikram Zohaib Akram 《Saudi Dental Journal》2019,31(1)
Aim
To investigate the expression of salivary S100A7 levels among patients with oral submucous fibrosis (OSF) and healthy controls.Method
A total number of 60 participants were included in the study (30 OSF cases and 30 healthy controls). Demographic data was collected using a structured baseline questionnaire. Salivary S100A7 levels were quantified using enzyme-linked immunosorbent assay. Data was analyzed using Student t-test. Pearson correlation test was used to evaluate correlation between S100A7 levels and independent variables such as frequency and duration of areca nut use, gutka use, and mouth opening.Results
The mean value of salivary S100A7 for OSF group was 0.275?ng/ml, whereas mean value of salivary S100A7 for healthy controls was 0.195?ng/ml. Student t-test indicated that there was statistically significantly higher levels of S100A7 in OSF group as compared to healthy controls (p?<?.001). When the clinical variables of individual groups were analysed, a significant negative correlation was found between salivary S100A7 and duration of areca nut (p?=?.009) and gutka chewing (p?=?.03), whereas a significant positive correlation was found for mouth opening (p?=?.04).Conclusion
OSF presented higher levels of salivary S100A7 levels as compared with healthy individuals and may be used as surrogate measure to identify subjects at risk for OSF. 相似文献53.
The Prokinetic,Laxative, and Antidiarrheal Effects of Morus nigra: Possible Muscarinic,Ca2+ Channel Blocking,and Antimuscarinic Mechanisms
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Anam Akhlaq Malik Hassan Mehmood Abdul Rehman Zohaib Ashraf Sadia Syed Samira Ahmed Bawany Anwarul‐Hassan Gilani Maimoona Ilyas Bina Shaheen Siddiqui 《Phytotherapy research : PTR》2016,30(8):1362-1376
Morus nigra Linn. (black mulberry) is used in gastrointestinal ailments. This study demonstrates gut modulatory properties of M. nigra. The prokinetic, laxative, and antidiarrheal activities of M. nigra were assessed in mice, while isolated rabbit jejunum and guinea‐pig ileum were used to explore insight into mechanism(s). At 30 and 70 mg/kg, the crude extract of M. nigra (Mn.Cr) exhibited atropine‐sensitive prokinetic and laxative effects, similar to carbachol (CCh). While at higher doses (100, 300, and 500 mg/kg), Mn.Cr offered protection against castor oil‐induced diarrhea. In rabbit jejunum, Mn.Cr and its chloroform fraction inhibited CCh‐induced contractions more potently compared with high K+ (80 mm ). Conversely, petroleum fraction was more potent against high‐K+‐induced contractions. At 0.01 mg/mL, Mn.Cr caused a parallel shift in acetylcholine concentration–response curves (CRCs) followed by a non‐parallel shift at 0.03 mg/mL, similar to dicyclomine. At further tested concentrations, Mn.Cr (0.1 and 0.3 mg/mL) and petroleum fraction suppressed Ca2+ CRCs, similar to verapamil. In guinea‐pig ileum, Mn.Cr, its aqueous and ethyl acetate fractions exhibited atropine‐sensitive gut stimulant activity along with additional uncharacterized excitatory response in the aqueous fraction only. These results suggest that black mulberry possesses prokinetic, laxative, and antidiarrheal effects, putatively mediated through cholinomimetic, antimuscarinic, and Ca2+ antagonist mechanisms, respectively. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Spontaneous esophageal rupture (Boerhaave syndrome) is uncommon in children. Delayed or missed diagnosis can lead to poor outcomes in terms of morbidity and mortality. To highlight the importance of early recognition and management of spontaneous esophageal rupture in children, we report a case of a 16-year-old boy who presented in the emergency department with acute chest pain after episodes of vomiting. 相似文献
56.
Nasim Yousaf David J. Gould Ebun Aganna Linda Hammond Rita M. Mirakian Mark D. Turner Graham A. Hitman Michael F. McDermott Yuti Chernajovsky 《Arthritis \u0026amp; Rheumatology》2005,52(9):2906-2916
Objective
To investigate the molecular consequences of expressing mutated forms of tumor necrosis factor receptor I (TNFRI) as found in patients with TNFR‐associated periodic syndrome (TRAPS).Methods
We cloned and expressed full‐length wild‐type (WT) and T50K and P46L variants of TNFRI using a new tightly regulated doxycycline‐dependent expression system. This system enabled the study of molecular interactions between these receptors at both physiologic and pathophysiologic levels of expression.Results
We used chemical crosslinking on the cell surface to show that WT and mutant forms of TNFRI, derived from TRAPS patients, interact in the absence of TNF ligand. Doxycycline‐controlled up‐regulation of one TNFRI allele, either WT or mutant, caused down‐regulation of the other allele, indicating dynamic control of cell surface assembly. We also demonstrated that increased expression of mutant TNFRI (T50K) was associated with a parallel increase in NF‐κB p65 (RelA) subunit activation, which did not occur with increased expression of WT TNFRI.Conclusion
The T50K TRAPS‐related variant is capable of sustaining inappropriate NF‐κB activation, resulting in persistent autoinflammation in target organs such as skin, synovial membrane, and the central nervous system. We conclude that some of the inflammatory processes seen in TRAPS do not involve direct interaction of TNF with its receptors, but that other proinflammatory mechanisms capable of up‐regulating TNFRI expression may cause cellular activation through the NF‐κB signaling pathway.57.
Safeer Abbas Ali Ahmed Ayesha Waheed Wasim Abbass Muhammad Yousaf Sbahat Shaukat Hisham Alabduljabbar Youssef Ahmed Awad 《Materials》2022,15(10)
Recycled rubber waste (RW) is produced at an alarming rate due to the deposition of 1.5 billion scrap tires annually around the globe, which causes serious threats to the environment due to its open land filling issues. This study investigates the potential application of RW in concrete structures for mitigating the alkali–silica reaction (ASR). Various proportions of RW (5%, 10%, 15%, 20%, and 25%) partially replaced the used aggregates. RW was procured from a local rubber recycling unit. Cubes, prisms, and mortar bar specimens were prepared using a mixture design recommended by ASTM C1260 and tested for evaluating the compressive and flexural strengths and expansion in an ASR conducive environment for specimens incorporating RW. It was observed that the compressive and flexural strength decreased for specimens incorporating RW compared to that of the control specimens without RW. For example, an 18% and an 8% decrease in compressive and flexural strengths, respectively, were observed for specimens with 5% of RW by aggregates volume at 28 days. Mortar bar specimens without RW showed an expansion of 0.23% and 0.28% at 14 and 28 days, respectively, indicating the potential ASR reactivity in accordance with ASTM C1260. A decrease in expansion was observed for mixtures incorporating RW. Specimens incorporating 20% of RW by aggregate volume showed expansions of 0.17% at 28 days, within the limit specified by ASTM C1260. Moreover, specimens incorporating RW showed a lower reduction in compressive and flexural strengths under an ASR conducive environment compared to that of the control specimen without RW. Micro-structural analysis also showed significant micro-cracking for specimens without RW due to ASR. However, no surface cracks were observed for specimens incorporating RW. It can be argued that the use of RW in the construction industry assists in reducing the landfill depositing issues with the additional benefit of limiting the ASR expansion. 相似文献
58.
Shea Stubbs Sakib Yousaf Iftikhar Khan 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2022,30(2):407
ObjectivesWith increasing awareness of the potential adverse impact of conventional surfactants on the environment and human health, there is mounting interest in the development of bio-based surfactants (which are deemed to be safer, more affordable, are in abundance, are biodegradable, biocompatible and possess scalability, mildness and performance in formulation) in personal care products.MethodA comprehensive literature review around alkyl polyglucosides (APGs) and sucrose esters (SEs) as bio-based surfactants, through the lens of the 12 green chemistry principles was conducted. An overview of the use of bio-based surfactants in personal care products was also provided.ResultsBio-based surfactants are derived primarily from natural sources (i.e. both the head and tail molecular group). One of the more common types of bio-based surfactants are those with carbohydrate head groups, where alkyl polyglucosides (APGs) and sucrose esters (SEs) lead this sub-category. As global regulations and user mandate for sustainability and safety increase, evidence to further support these bio-based surfactants as alternatives to their petrochemical counterparts is advantageous. Use of the green chemistry framework is a suitable way to do this. While many of the discussed principles are enforced industrially, others have only yet been applied at a laboratory scale or are not apparent in literature.ConclusionMany of the principles of green chemistry are currently used in the synthesis of APGs and SEs. These and other bio-based surfactants should, therefore, be considered suitable and sustainable alternatives to conventional surfactants. To further encourage the use of these novel surfactants, industry must make an effort to implement and improve the use of the remaining principles at a commercial level.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s40199-022-00450-y. 相似文献
59.
Hale M Thompson Brihat Sharma Dale L Smith Sameer Bhalla Ihuoma Erondu Aniruddha Hazra Yousaf Ilyas Paul Pachwicewicz Neeral K Sheth Neeraj Chhabra Niranjan S Karnik Majid Afshar 《JMIR Public Health and Surveillance》2022,8(12)
BackgroundThe COVID-19 pandemic has exacerbated health inequities in the United States. People with unhealthy opioid use (UOU) may face disproportionate challenges with COVID-19 precautions, and the pandemic has disrupted access to opioids and UOU treatments. UOU impairs the immunological, cardiovascular, pulmonary, renal, and neurological systems and may increase severity of outcomes for COVID-19.ObjectiveWe applied machine learning techniques to explore clinical presentations of hospitalized patients with UOU and COVID-19 and to test the association between UOU and COVID-19 disease severity.MethodsThis retrospective, cross-sectional cohort study was conducted based on data from 4110 electronic health record patient encounters at an academic health center in Chicago between January 1, 2020, and December 31, 2020. The inclusion criterion was an unplanned admission of a patient aged ≥18 years; encounters were counted as COVID-19-positive if there was a positive test for COVID-19 or 2 COVID-19 International Classification of Disease, Tenth Revision codes. Using a predefined cutoff with optimal sensitivity and specificity to identify UOU, we ran a machine learning UOU classifier on the data for patients with COVID-19 to estimate the subcohort of patients with UOU. Topic modeling was used to explore and compare the clinical presentations documented for 2 subgroups: encounters with UOU and COVID-19 and those with no UOU and COVID-19. Mixed effects logistic regression accounted for multiple encounters for some patients and tested the association between UOU and COVID-19 outcome severity. Severity was measured with 3 utilization metrics: low-severity unplanned admission, medium-severity unplanned admission and receiving mechanical ventilation, and high-severity unplanned admission with in-hospital death. All models controlled for age, sex, race/ethnicity, insurance status, and BMI.ResultsTopic modeling yielded 10 topics per subgroup and highlighted unique comorbidities associated with UOU and COVID-19 (eg, HIV) and no UOU and COVID-19 (eg, diabetes). In the regression analysis, each incremental increase in the classifier’s predicted probability of UOU was associated with 1.16 higher odds of COVID-19 outcome severity (odds ratio 1.16, 95% CI 1.04-1.29; P=.009).ConclusionsAmong patients hospitalized with COVID-19, UOU is an independent risk factor associated with greater outcome severity, including in-hospital death. Social determinants of health and opioid-related overdose are unique comorbidities in the clinical presentation of the UOU patient subgroup. Additional research is needed on the role of COVID-19 therapeutics and inpatient management of acute COVID-19 pneumonia for patients with UOU. Further research is needed to test associations between expanded evidence-based harm reduction strategies for UOU and vaccination rates, hospitalizations, and risks for overdose and death among people with UOU and COVID-19. Machine learning techniques may offer more exhaustive means for cohort discovery and a novel mixed methods approach to population health. 相似文献
60.
Yuzheng Lu M. A. K. Yousaf Shah Naveed Mushtaq Muhammad Yousaf Peter D. Lund Bin Zhu Muhammad Imran Asghar 《RSC advances》2022,12(38):24480
Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs). Here an A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ is proposed for low-temperature solid oxide fuel cells (LT-SOFCs). A fuel cell with a structure of Ni/NCAL-Sr0.7Co0.3FeO3−δ–NCAL/Ni reached a promising performance of 771 mW cm−2 at 550 °C. Moreover, appropriate doping of cobalt at the A-site resulted in enhanced charge carrier transportation yielding an ionic conductivity of >0.1 S cm−1 at 550 °C. A high OCV of 1.05 V confirmed that neither short-circuiting nor power loss occurred during the operation of the prepared SOFC device. A modified composition of Sr0.5Co0.5FeO3−δ and Sr0.3Co0.7FeO3−δ also reached good fuel cell performance of 542 and 345 mW cm−2, respectively. The energy bandgap analysis confirmed optimal cobalt doping into the A-site of the prepared perovskite structure improved the charge transportation effect. Moreover, XPS spectra showed how the Co-doping into the A-site enhanced O-vacancies, which improve the transport of oxide ions. The present work shows that Sr0.7Co0.3FeO3−δ is a promising electrolyte for LT-SOFCs. Its performance can be boosted with Co-doping to tune the energy band structure.Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs). 相似文献