Surface chemistry and spectroscopy studies on 1,4-naphthoquinone in cell membrane models using Langmuir monolayers

Investigating the role of drugs whose pharmaceutical activity is associated with cell membranes is fundamental to comprehending the biochemical processes that occur on membrane surfaces. in this work, we examined the action of 1,4-naphthoquinone in lipid Langmuir monolayers at the air-water interface, which served as a model for half of a membrane, and investigated the molecular interactions involved with tensiometry and vibrational spectroscopy. the surface pressure-area isotherms exhibited a noticeable shift to a lower area in relation to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dihexadecanoyl-sn-glycero-3-phospho-L-serine (DPPS) lipid monolayers, which indicated a disruption of the monolayer structure and solubilisation of the lipids towards the aqueous subphase. To better correlate to the action of this drug in biological membrane events, cell cultures that represented tumorigenic and non-tumorigenic cells were spread onto the air-water interface, and 1,4-naphthoquinone was then incorporated. While only slight changes were observed in the non-tumorigenic cells upon drug incorporation, significant changes were observed in the tumorigenic cells, on which the organisation of the Langmuir monolayers was disrupted as evidenced by tensiometry and vibrational spectroscopy. This work then shows that this drug interacts preferentially for specific surfaces. in simplified models, it has a higher effect for the negative charged DPPS rather than the zwitterionic DPPC; and for complex cell cultures, 1,4-naphthoquinone presents a more significant effect for that representing tumorigenic cells. (c) 2013 Elsevier Inc. All rights reserved.Universidade Federal de São Paulo, Diadema, SP, BrazilUniversidade Federal de São Paulo, Diadema, SP, BrazilWeb of Scienc

Speech resonance after septoplasty in a patient with bilateral cleft lip and palate

Purpose: The nasal airway is an important regulator of the pressures generated in speech when velopharyngeal function is altered. Patients with cleft palate often have nasal obstruction and increased nasal resistance, which can compensate a possible velopharyngeal dysfunction (VPD) and mask hypernasality. Clinical report: A 16 yearold patient, male, underwent nasometric and rhinomanometric assessment before and one year after septoplasty and bilateral inferior turbinectomy surgery. Nasometry was used to evaluate the nasalance scores (acoustic correlate of nasality) during the reading of a set of 5 sentences containing predominantly nasal sounds (nasal text) and a set containing exclusively oral sounds (oral text). Rhinomanometry permits the determination of the minimum nasal cross-sectional area (CSA) by the simultaneous measurement of the differential transnasal pressure and nasal air flow during resting breathing. Before surgery, the nasalance values were 40% and 26% in nasal and oral text, respectively, indicating hyponasality. Rhinomanometry showed that the values obtained for nasal area were 0.571cm2 and 0.094cm2 in the right and left sides respectively indicating a reduced nasal CSA of the left side. After surgery, there was an increase in nasalance to 55% in the nasal text and to 40% in the oral text, indicating hypernasality. Rhinomanometry indicated that nasal area were 0.237cm2 and 0.287cm2, in the right and left sides respectively. Conclusion: The surgery resulted in an increase of the nasal area and improving nasal patency. However, hypernasality was demonstrated. These results confirm what has already been reported by Warren et al (1992) in stating that in the presence of VPD "a good nose for breathing is often a bad nose for speech"

Geographic Tongue and Fissured Tongue in 348 Patients with Psoriasis: Correlation with Disease Severity

Geographic tongue (GT) and fissured tongue (FT) are the more frequent oral lesions in patients with psoriasis. The aims of this study were to compare the prevalence of GT/FT between psoriasis group (PG) and healthy controls (HC) and investigate the correlation between GT/FT and psoriasis severity using the PASI and age of psoriasis onset. Three hundred and forty-eight PG and 348 HC were selected. According to the age of psoriasis onset, the individuals were classified as having early psoriasis and late psoriasis. The severity of vulgaris psoriasis was determined according to PASI. A follow-up was conducted in patients with psoriasis vulgaris (PV) with GT to evaluate the progression of oral and cutaneous lesions. The FT and GT were more frequent in PG than in HC. The incidence of GT was higher in patients with early psoriasis and that of FT in late-psoriasis. There is association between psoriasis intensity and GT; and a higher monthly decrease of PASI score in patients without GT. The presence of GT and FT is higher in PG than in the HC. GT is associated with disease severity and may be a marker of the psoriasis severity

Evaluation of HIV protease and nucleoside reverse transcriptase inhibitors on proliferation, necrosis, apoptosis in intestinal epithelial cells and electrolyte and water transport and epithelial barrier function in mice

<p>Abstract</p> <p>Background</p> <p>Protease inhibitors (PI's) and reverse transcriptase drugs are important components of highly active antiretroviral therapy (HAART) for treating human acquired immunodeficiency syndrome (AIDS). Long-term clinical therapeutic efficacy and treatment compliance of these agents have been limited by undesirable side-effects, such as diarrhea. This study aims to investigate the effects of selected antiretroviral agents on intestinal histopathology and function <it>in vivo </it>and on cell proliferation and death <it>in vitro</it>.</p> <p>Methods</p> <p>Selected antiretroviral drugs were given orally over 7 days, to Swiss mice, as follows: 100 mg/kg of nelfinavir (NFV), indinavir (IDV), didanosine (DDI) or 50 mg/kg of zidovudine (AZT). Intestinal permeability measured by lactulose and mannitol assays; net water and electrolyte transport, in perfused intestinal segments; and small intestinal morphology and cell apoptosis were assessed in treated and control mice. <it>In vitro </it>cell proliferation was evaluated using the WST-1 reagent and apoptosis and necrosis by flow cytometry analysis.</p> <p>Results</p> <p>NFV, IDV, AZT and DDI caused significant reductions in duodenal and in jejunal villus length (p < 0.05). IDV and AZT increased crypt depth in the duodenum and AZT increased crypt depth in the jejunum. NFV, AZT and DDI significantly decreased ileal crypt depth. All selected antiretroviral drugs significantly increased net water secretion and electrolyte secretion, except for DDI, which did not alter water or chloride secretion. Additionally, only NFV significantly increased mannitol and lactulose absorption. NFV and IDV caused a significant reduction in cell proliferation <it>in vitro </it>at both 24 h and 48 h. DDI and AZT did not alter cell proliferation. There was a significant increase in apoptosis rates in IEC-6 cells after 24 h with 70 ug/mL of NFV (control: 4.7% vs NFV: 22%) while IDV, AZT and DDI did not show any significant changes in apoptosis compared to the control group. In jejunal sections, IDV and NFV significantly increased the number of TUNEL positive cells.</p> <p>Conclusion</p> <p>The PI's, NFV and IDV, increased cell apoptosis <it>in vivo</it>, water and electrolyte secretion and intestinal permeability and decreased villus length and cell proliferation. NFV was the only drug tested that increased cell apoptosis <it>in vitro</it>. The nucleoside reverse transcriptase inhibitors, AZT and DDI, did not affect cell apoptosis or proliferation. These findings may partly explain the intestinal side-effects associated with PI's.</p

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio