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51.
Objective:
Orthognathic surgeries and distraction osteogenesis (DO) of the jaw bones cause a change in the pharyngeal airway space (PAS). The aim of our study was to evaluate the magnitude of changes occurring in the pharyngeal airway after mandibular set-back surgeries and DO of maxilla/mandible.Materials and Methods:
The study undertaken was a retrospective cephalometric study. Subjects included in our study had undergone mandibular set-back surgery or DO of maxilla/mandible. Lateral cephalograms of the subjects taken pre-operatively (T0), immediate post-operatively (T1) and after a minimum follow-up period of 6 months (T2) were studied. The cephalograms were traced manually and the following parameters were evaluated: Surface area of the PAS, pharyngeal airway width at the level of the base of the tongue, position of the hyoid bone and the tongue. Repeated measure ANOVA test was done to assess the presence of any significant changes in the proposed parameters at T0, T1 and T2. A correlation analysis was made between the mandibular/maxillary movements and the corresponding changes in the PAS.Results:
Surgical movements of maxilla and mandible do have an effect on the pharyngeal airway.Conclusion:
It was clearly evident that the effects of mandibular movements on the PAS and the hyoid bone is more significant than the maxillary movements.KEY WORDS: Distraction osteogenesis, orthognathic surgery, pharyngeal airway space 相似文献52.
David W. Ellison Kenneth D. Aldape David Capper Maryam Fouladi Mark R. Gilbert Richard J. Gilbertson Cynthia Hawkins Thomas E. Merchant Kristian Pajtler Sriram Venneti David N. Louis 《Brain pathology (Zurich, Switzerland)》2020,30(5):863-866
Advances in our understanding of the biological basis and molecular characteristics of ependymal tumors since the latest iteration of the World Health Organization (WHO) classification of CNS tumors (2016) have prompted the cIMPACT‐NOW group to recommend a new classification. Separation of ependymal tumors by anatomic site is an important principle of the new classification and was prompted by methylome profiling data to indicate that molecular groups of ependymal tumors in the posterior fossa and supratentorial and spinal compartments are distinct. Common recurrent genetic or epigenetic alterations found in tumors belonging to the main molecular groups have been used to define tumor types at intracranial sites; C11orf95 and YAP1 fusion genes for supratentorial tumors and two types of posterior fossa ependymoma defined by methylation group, PFA and PFB. A recently described type of aggressive spinal ependymoma with MYCN amplification has also been included. Myxopapillary ependymoma and subependymoma have been retained as histopathologically defined tumor types, but the classification has dropped the distinction between classic and anaplastic ependymoma. While the cIMPACT‐NOW group considered that data to inform assignment of grade to molecularly defined ependymomas are insufficiently mature, it recommends assigning WHO grade 2 to myxopapillary ependymoma and allows grade 2 or grade 3 to be assigned to ependymomas not defined by molecular status. 相似文献
53.
BiVO4 is a promising photoanode material for the photoelectrochemical (PEC) oxidation of water; however, its poor charge transfer, transport, and slow surface catalytic activity limit the expected theoretical efficiency. Herein, we have investigated the effect of Mo doping on SnO2 buffer layer coated BiVO4 for PEC water splitting. SnO2 and Mo doped BiVO4 layers are coated with layer by layer deposition through a precursor solution based spin coating technique followed by annealing. At 5% doping of Mo, the sample (SBM5) shows a maximum current density of 1.65 mA cm−2 at 1.64 V vs. RHEl in 0.1 M phosphate buffer solution under AM 1.5 G solar simulator, which is about 154% improvement over the sample without Mo (SBM0). The significant improvement in the photocurrent upon Mo doping is due to the improvement of various bulk and interfacial properties in the materials as measured by UV-vis spectroscopy, electrochemical impedance spectroscopy (EIS), Mott–Schottky analysis, and open-circuit photovoltage (OCPV). The charge transfer kinetics at the BiVO4/electrolyte interface are investigated to simulate the oxygen evolution process in photoelectrochemical water oxidation in the feedback mode of scanning electrochemical microscopy (SECM) using 2 mM [Fe(CN)6]3− as the redox couple. SECM investigation reveals a significant improvement in effective hole transfer rate constant from 2.18 cm s−1 to 7.56 cm s−1 for the hole transfer reaction from the valence band of BiVO4 to [Fe(CN)6]4− to oxidize into [Fe(CN)6]3− with the Mo doping in BiVO4. Results suggest that Mo6+ doping facilitates the hole transfer and suppresses the back reaction. The synergistic effect of fast forward and backward conversion of Mo6+ to Mo5+ expected to facilitate the V5+ to V4+ which has an important step to improve the photocurrent.BiVO4 is a promising photoanode material for the photoelectrochemical (PEC) oxidation of water; however, its poor charge transfer, transport, and slow surface catalytic activity limit the expected theoretical efficiency. 相似文献
54.
Ritika Mullick Sriram Annavajjhala Prashansa Thakur Ayushi Mohapatra Rohit Shetty Sharon DSouza 《Indian journal of ophthalmology》2021,69(12):3473
Purpose:To evaluate the effect of topical cyclosporine 0.05% and osmoprotective lubricating eye drops on patients with dry eye disease (DED) with inflammation as measured by raised tear matrix metalloproteinases (MMP-9).Methods:This prospective study included 106 eyes of 53 patients diagnosed with DED based on any of the following DED criteria (Ocular Surface Disease Index [OSDI] score >12, tear film breakup time [TBUT] <10 s, Schirmer’s I test result <10 mm/5 min, ocular surface staining). Ocular surface inflammation was assessed by assessing MMP-9 positivity from tears of the patients in the study (Inflammadry kit Quidel corporation). Patients were prescribed osmoprotective lubricating eye drops (Osmodrops, Cipla Ltd) four times a day and cyclosporine A 0.05% eye drops (Imudrops, Cipla Ltd) twice a day for 6 months. Efficacy of the formulations was evaluated by OSDI scores, Schirmer’s test, TBUT change, reduction in ocular surface staining, and reduction in MMP-9 levels after 6 months of usage. Check P value and add from resultsResults:After 6 months of topical therapy, improvement was observed in OSDI scores (mean pretreatment: 25.7 ± 12.8, and mean posttreatment: 15.2 ± 8.4), P < 0.001. There was also reduction number of patients who were MMP-9 positive. Out of 75 eyes that tested MMP-9 positive, 70.66% showed reduction in MMP-9 levels P < 0.0001). Ocular surface staining also improved.Conclusion:Topical osmoprotective lubricating eye drops and cyclosporine A 0.05% reduce inflammation in cases of DED, which correlates with improvement in OSDI scores, ocular surface staining, and reduction in inflammation as measured by levels of tear MMP-9. 相似文献
55.
Ivneet Banga Anirban Paul Abha Umesh Sardesai Sriram Muthukumar Shalini Prasad 《RSC advances》2021,11(33):20519
Breath analytics is currently being explored for the development of point-of-care devices in non-invasive disease detection. It is based on the measurement of volatile organic compounds (VOCs) and gases that are produced by the body because of the metabolic pathways. The levels of these metabolites vary due to alteration in the endogenous oxidative stress-related metabolic pathways and can be correlated to understand the underlying disease condition. The levels of exhaled hydrocarbons in human breath can be used to design a rapid, easy to use method for lung cancer detection. This work outlines the development of an electrochemical sensing platform that can be used for the non-invasive diagnosis of lung cancer by monitoring isopentane levels in breath. This electrochemical sensor platform involves the use of [BMIM]BF4@ZIF-8 for sensing the target analyte. This synthesized nanocomposite offers advantages for gas sensing applications as it possesses unique properties such as an electrochemically active Room Temperature Ionic Liquid (RTIL) and a crosslinking Metal Organic Framework (MOF) that provides increased surface area for gas absorption. This is the first report of a hydrocarbon-based sensor platform developed for lung cancer diagnosis. The developed sensor platform displays sensitivity and specificity for the detection of isopentane up to 600 parts-per-billion. We performed structural and morphological characterization of the synthesized nanocomposite using various analytical techniques such as PXRD, FESEM, FTIR, and DLS. We further analyzed the electrochemical activity of the synthesized nanocomposite using a standard glassy carbon electrode. The application of the nanocomposite for isopentane sensing was done using a commercially available carbon screen printed electrode. The results so obtained helped in strengthening our hypothesis and serve as a proof-of-concept for the development of a breathomics-enabled electrochemical strategy. We illustrated the specificity of the developed nanocomposite by cross-reactivity studies. We envision that the detection platform will allow sensitive and specific sensing of isopentane levels such that it can used for point of care applications in noninvasive and early diagnosis of lung cancer, thereby leading to its early treatment and decrease in mortality rate.A novel synthesized [BMIM]BF4@ZIF-8 nanocomposite for electrochemical sensing of isopentane as a biomarker for lung cancer diagnosis. 相似文献
56.
57.
The development of multidrug resistance (MDR) causes problems in the chemotherapy of human cancer. The present study was designed to evaluate and establish the role of Eclipta alba as MDR reversal agent using multidrug resistant hepatocellular carcinoma cell line (DR-HepG2). To develop DR-HepG2, hepatocellular carcinoma cell line (HepG2) was transfected with 2-Acetylaminofluorene (AAF) and Aflatoxin B1 (AFB). Cytotoxic effects of the Eclipta alba hydroalcoholic extract (EAE) and standard anti-ancer drug Doxorubicin (DOX) were determined in DR-HepG2 and the parental cells HepG2 using MTT assay. The expression level of MDR1 gene and P-glycoprotein (P-gp) level was analyzed by RT-PCR and western blotting. From the present investigation, it was found that EAE (10 and 20 μg/ml) could significantly inhibit cell proliferation in DR-HepG2 whereas DOX (0.5 μg/ml) could not because of enhancement effect of MDR1/P-gp. This study demonstrated for the first time the antiproliferative activities of EAE in multidrug resistant DR-HepG2 cells. The findings revealed that Eclipta alba components are effective inhibitors of MDR1/P-gp. 相似文献
58.
59.
60.
Exposure to pentachlorophenol (PCP) strongly intensifies theformation of mouse hepatic DNA adducts elicited by oral administrationof tamoxifen (TAM), as previously shown by 32P-postlabeling.To explain this effect, PCP was proposed to interfere with thedetoxication by sulfate conjugation of an as yet unidentifiedhydroxylated proximate TAM metabolite. A comparison of the presentand earlier results shows that the hepatic TAM adduct patternin female ICR mice depended on the route of administration ofTAM (120 µmol/kg), with oral administration primarilyeliciting formation of more polar adducts (termed group I adducts),while after i.p. administration less polar adducts (group II)predominated over group I adducts by a factor of 17.5. All theseadducts were also formed in female SpragueDawley ratsafter i.p. dosing with TAM, but total adduct levels were 3.5-to 5-fold higher than in mice. After four daily i.p. treatments,TAM adducts accumulated in mouse liver DNA in a non-linear fashion.Adduct levels were 3050 times lower in mouse kidney andlung than in liver. The phenolic metabolite 4-hydroxy TAM (120µimol/kg) exclusively led to formation of polar (groupI) hepatic adducts, and this process was stimulated 8-fold bycoadministration of PCP (75 µimol/kg). Co-administrationof PCP with the parent compound led to an 11-fold enhancementof group I adduct formation; simultaneously, levels of groupII adducts were suppressed 6-fold. Another inhibitor of sulfateconjugation, 2,6-dichloro-4-nitrophenol, unlike PCP, had noeffect on group I adducts, but it reduced group II adduct formation2.2-fold. The PCP metabolite 2,3,5,6-tetrachlorohydroquinone(75 µimol/kg) did not significantly affect any major TAMadduct, suggesting that PCP itself was the active compound.Similar to group II TAM adducts, the formation of hepatic safroleDNAadducts was inhibited in female ICR mice by both sulfotransferaseinhibitors, consistent with the proposal that metabolic 相似文献