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1.
Cytotoxic Effects of Betel Quid and Areca Nut Aqueous Extracts on Mouse Fibroblast,Human Mouth-Ordinary-Epithelium 1 and Human Oral Squamous Cell Carcinoma Cell Lines 下载免费PDF全文
Badr Abdullah Al-TayarAzlina AhmadMohamad Ezany YusoffSiti Fadilah AbdullahNoor Khairiena MohamadSiti Nurnasihah Md HashimShosei KishidaMichiko KishidaNorifumi NakamuraToshiro KibeMasitah Hayati Harun 《Asian Pacific journal of cancer prevention》2020,21(4):1005-1009
Background: Betel quid chewing is more common among the older generation in rural areas of Malaysia. Oral cancer in Asia has been associated with the habit of chewing betel quid and areca nut. Objective: This study aims to investigate the cytotoxic effects of betel quid and areca nut extracts on the fibroblast (L929), mouth-ordinary-epithelium 1 (MOE1) and oral squamous cell carcinoma (HSC-2) cell lines. Methods: L929, MOE1 and HSC-2 cells were treated with 0.1, 0.2 and 0.4 g/ml of betel quid and areca nut extracts for 24, 48 and 72 h. MTT assay was performed to assess the cell viability. Results: Both extracts, regardless of concentration, significantly reduced the cell viability of L929 compared with the control (P<0.05). Cell viability of MOE1 was significantly enhanced by all betel quid concentrations compared with the control (P<0.05). By contrast, 0.4 g/ml of areca nut extract significantly reduced the cell viability of MOE1 at 48 and 72 h of incubation. Cell viability of HSC-2 was significantly lowered by all areca nut extracts, but 0.4 g/ml of betel quid significantly increased the cell viability of HSC-2 (P<0.05). Conclusion: Areca nut extract is cytotoxic to L929 and HSC-2, whereas the lower concentrations of areca nut extract significantly increased the cell viability of MOE1 compared to the higher concentration and control group. Although betel quid extract is cytotoxic to L929, the same effect is not observed in MOE1 and HSC-2 cell lines. Further investigations are needed to clarify the mechanism of action. 相似文献
2.
Ihsan A. Badr 《International ophthalmology》1993,17(3):155-160
The region is characterized by diversity in cultural, political, economic and health conditions. Blindness in the region varies from 6.4% to 0.2% with cataract ranking highly as an underlying cause. There is a need to develop national policies to deliver affordable, technically suitable, and cost effective management plans to reduce cataract. Economic, demographic, health, and manpower statistics are essential information to be considered in formulating such policies. 相似文献
3.
Contin Educ Anaesth Crit 相似文献
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Maximal dynamic expiratory pressures are higher when forced expiration is preceded by a fast inspiration to total lung capacity
(TLC) than when preceded by a slow inspiration and a few seconds pause at TLC. We hypothesized that these pressure differences
are due to the stretch-shorten cycle (SSC), which refers to enhancement of muscle force when a concentric muscle contraction
is immediately preceded by an eccentric contraction. Seven volunteers [36 (2) years; mean (SEM)] performed maximal forced
expirations against minimal resistance with fast (F) or slow (S) maneuvers. F maneuvers consisted of a fast inspiration to
TLC followed immediately by a fast expiration, whereas S consisted of a slow inspiration to TLC and a 4- to 5-s pause at TLC
prior to forced expiration. We measured esophageal pressure (P
es), peak expiratory flow rate (PEFR), and the EMG activity of the transversus abdominis (Tr) by means of intramuscular fine-wire
electrodes. The subjects performed several runs of each maneuver in a random order, and runs with the greatest expiratory
P
es were analyzed. In comparison with S, F yielded greater P
es [182 (15) versus 167 (15) cmH2O; P=0.003)] but similar PEFR [9.8 (0.7) versus 9.6 (0.7) l/s, P>0.05] and EMG activity of the Tr during forced expiration [221 (31) versus 208 (34) a.u., P>0.05]. Further analysis revealed significant EMG activity of Tr during end-inspiration (eccentric contraction) with F maneuvers
only [73 (22) versus 32 (17) a.u., P<0.05]. We conclude that the ability of expiratory muscles to generate greater P
es with F maneuvers is related to the sequence of an eccentric contraction, which is followed immediately by concentric contraction
in a manner analogous to SSC described in skeletal muscles.
Electronic Publication 相似文献
7.
Azza Farag Mostafa Hammam Nada Alnaidany Eman Badr Mustafa Elshaib Aliaa El-Swah Wafaa Shehata 《The Journal of clinical and aesthetic dermatology》2021,14(2):14
BACKGROUND: Melasma is a chronic hypermelanotic disorder that is challenging to treat; no single effective therapeutic agent for it has been discovered. Methimazole, an oral antithyroid drug, has a skin depigmenting effect when used topically. OBJECTIVE: We sought to evaluate the efficacy and safety of methimazole, applied during microneedling sessions and additional topical use in between sessions, for the treatment of melasma. METHODS: This split-face study included 30 Egyptian patients with melasma, each of whom received 12 microneedling sessions once per week for 12 weeks followed by topical methimazole on the right side of face and placebo on the left side. In between the sessions, topical methimazole 5% cream was applied twice per day on the right side and placebo on the left side. Assessments were performed using the Hemi-melasma Area and Severity Index (hemi-MASI) percentage of improvement, patient satisfaction, dermoscopy, and thyroid-stimulating hormone (TSH) serum levels. RESULTS: There were significant clinical and dermoscopic improvements; hemi-MASI scores on the methimazole-treated right sides were decreased (p<0.001). The percent of hemi-MASI score improvement was significantly associated with the malar pattern (p=0.031) and epidermal type (p=0.04) of melasma. About 70 percent of our studied patients reported being satisfied with their treatment response (7% excellent, 33% good, 30% fair). No significant local or systemic side effects were observed. Pre- and posttreatment serum TSH levels were within the normal range in all treated cases. CONCLUSIONS: Methimazole has the potential to be a safe and promising therapeutic agent for the treatment of melasma via dermapen-delivered microneedling sessions with topical use in between sessions. 相似文献
8.
A nuclear gene of eubacterial origin in Euglena gracilis reflects cryptic endosymbioses during protist evolution. 总被引:1,自引:0,他引:1 下载免费PDF全文
K Henze A Badr M Wettern R Cerff W Martin 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(20):9122-9126
Genes for glycolytic and Calvin-cycle glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of higher eukaryotes derive from ancient gene duplications which occurred in eubacterial genomes; both were transferred to the nucleus during the course of endosymbiosis. We have cloned cDNAs encoding chloroplast and cytosolic GAPDH from the early-branching photosynthetic protist Euglena gracilis and have determined the structure of its nuclear gene for cytosolic GAPDH. The gene contains four introns which possess unusual secondary structures, do not obey the GT-AG rule, and are flanked by 2- to 3-bp direct repeats. A gene phylogeny for these sequences in the context of eubacterial homologues indicates that euglenozoa, like higher eukaryotes, have obtained their GAPDH genes from eubacteria via endosymbiotic (organelle-to-nucleus) gene transfer. The data further suggest that the early-branching protists Giardia lamblia and Entamoeba histolytica--which lack mitochondria--and portions of the trypanosome lineage have acquired GAPDH genes from eubacterial donors which did not ultimately give rise to contemporary membrane-bound organelles. Evidence that "cryptic" (possibly ephemeral) endosymbioses during evolution may have entailed successful gene transfer is preserved in protist nuclear gene sequences. 相似文献
9.
Despite rising interest in the health problems of the elderly, information on senescence-related alterations in essential metabolic pathways and their responses to various chemicals is scarce. Although peroxisomal pathways are involved in a multitude of cellular functions, little attention has been given to the potential relationship between senescence of these organelles and the process of aging and disease. Although the prevailing experimental evidence points to a decline in liver peroxisomal enzyme activities and a muted response to peroxisome-proliferating chemicals in aged animals, it is also evident that aged animals are more susceptible, in comparison to their young counterparts, to the hepatocarcinogenic effects of these chemicals. Furthermore, little is known about extraperoxisomal effects of peroxisome proliferators in aged animals. This review evaluates published studies on the impact of aging on basal hepatic peroxisomal metabolism, response to peroxisome proliferators, and changes in signal transduction pathways involved in these processes, with the aim of stimulating research efforts in this important area. The potential intricate relationship among senescent peroxisomes, aged hepatocytes, and health are also discussed. 相似文献
10.
Dahniya MH Hanna RM Grexa E Cherian MJ Niazy MN Badr S Ibrahim F al-Othman AN 《Australasian radiology》1999,43(4):444-447
Most intra-abdominal and other types of fluid collections are now successfully drained percutaneously under image guidance. The utility of percutaneous drainage of tuberculous abscesses, especially those associated with osseous changes, is, however, less well established. Six patients with tuberculous iliopsoas abscesses were successfully managed by percutaneous drainage combined with antituberculous therapy. The abscesses were bilateral in one patient and unilateral in the other five. Drainage was by needle aspiration under ultrasound (US) guidance in one patient, and by catheter under CT guidance in the other patients. Three patients had associated osseous changes. There were no procedural complications. Tuberculous iliopsoas abscess can be successfully treated by percutaneous drainage and appropriate antituberculous therapy. 相似文献