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1.
Environ Sci Technol ; 58(14): 6435-6443, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551393

RESUMO

Nanovoids within a polyamide layer play an important role in the separation performance of thin-film composite (TFC) reverse osmosis (RO) membranes. To form more extensive nanovoids for enhanced performance, one commonly used method is to incorporate sacrificial nanofillers in the polyamide layer during the exothermic interfacial polymerization (IP) reaction, followed by some post-etching processes. However, these post-treatments could harm the membrane integrity, thereby leading to reduced selectivity. In this study, we applied in situ self-etchable sacrificial nanofillers by taking advantage of the strong acid and heat generated in IP. CaCO3 nanoparticles (nCaCO3) were used as the model nanofillers, which can be in situ etched by reacting with H+ to leave void nanostructures behind. This reaction can further degas CO2 nanobubbles assisted by heat in IP to form more nanovoids in the polyamide layer. These nanovoids can facilitate water transport by enlarging the effective surface filtration area of the polyamide and reducing hydraulic resistance to significantly enhance water permeance. The correlations between the nanovoid properties and membrane performance were systematically analyzed. We further demonstrate that the nCaCO3-tailored membrane can improve membrane antifouling propensity and rejections to boron and As(III) compared with the control. This study investigated a novel strategy of applying self-etchable gas precursors to engrave the polyamide layer for enhanced membrane performance, which provides new insights into the design and synthesis of TFC membranes.


Assuntos
Incrustação Biológica , Nanopartículas , Osmose , Nylons/química , Gravuras e Gravação , Membranas Artificiais , Água/química
2.
Acta Pharmacol Sin ; 45(4): 867-878, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38114644

RESUMO

Osimertinib (Osi) is widely used as a first-line treatment for non-small cell lung cancer (NSCLC) with EGFR mutations. However, the majority of patients treated with Osi eventually relapse within a year. The mechanisms of Osi resistance remain largely unexplored, and efficient strategies to reverse the resistance are urgently needed. Here, we developed a lactoferrin-modified liposomal codelivery system for the combination therapy of Osi and panobinostat (Pan), an epigenetic regulator of histone acetylation. We demonstrated that the codelivery liposomes could efficiently repolarize tumor-associated macrophages (TAM) from the M2 to M1 phenotype and reverse the epithelial-mesenchymal transition (EMT)-associated drug resistance in the tumor cells, as well as suppress glycolysis, lactic acid production, and angiogenesis. Our results suggested that the combination therapy of Osi and Pan mediated by liposomal codelivery is a promising strategy for overcoming Osi resistance in NSCLC.


Assuntos
Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas , Resistencia a Medicamentos Antineoplásicos , Epigênese Genética , Indóis , Neoplasias Pulmonares , Panobinostat , Inibidores de Proteínas Quinases , Pirimidinas , Humanos , Acrilamidas/farmacologia , Acrilamidas/uso terapêutico , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Lipossomos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Panobinostat/farmacologia , Panobinostat/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia
3.
BMC Genomics ; 24(1): 178, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37020178

RESUMO

BACKGROUND: Fusarium crown rot (FCR) is a chronic disease of cereals worldwide. Compared with tetraploid wheat, hexaploid wheat is more resistant to FCR infection. The underlying reasons for the differences are still not clear. In this study, we compared FCR responses of 10 synthetic hexaploid wheats (SHWs) and their tetraploid and diploid parents. We then performed transcriptome analysis to uncover the molecular mechanism of FCR on these SHWs and their parents. RESULTS: We observed higher levels of FCR resistance in the SHWs compared with their tetraploid parents. The transcriptome analysis suggested that multiple defense pathways responsive to FCR infection were upregulated in the SHWs. Notably, phenylalanine ammonia lyase (PAL) genes, involved in lignin and salicylic acid (SA) biosynthesis, exhibited a higher level of expression to FCR infection in the SHWs. Physiological and biochemical analysis validated that PAL activity and SA and lignin contents of the stem bases were higher in SHWs than in their tetraploid parents. CONCLUSION: Overall, these findings imply that improved FCR resistance in SHWs compared with their tetraploid parents is probably related to higher levels of response on PAL-mediated lignin and SA biosynthesis pathways.


Assuntos
Fusarium , Fusarium/fisiologia , Tetraploidia , Lignina , Poaceae , Genótipo , Doenças das Plantas/genética , Resistência à Doença/genética
4.
Environ Sci Technol ; 57(6): 2548-2556, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36719958

RESUMO

Surface roughness has crucial influence on the fouling propensity of thin film composite (TFC) polyamide reverse osmosis (RO) membranes. A common wisdom is that rougher membranes tend to experience more severe fouling. In this study, we compared the fouling behaviors of a smooth polyamide membrane (RO-s) and a nanovoid-containing rough polyamide membrane (RO-r). Contrary to the traditional belief, we observed more severe fouling for RO-s, which can be ascribed to its uneven flux distribution caused by the "funnel effect". Additional tracer filtration tests using gold nanoparticles revealed a more patchlike particle deposition pattern, confirming the adverse impact of "funnel effect" on membrane water transport. In contrast, the experimentally observed lower fouling propensity of the nanovoid-containing rough membrane can be explained by: (1) the weakened "funnel effect" thanks to the presence of nanovoids, which can regulate the water transport pathway through the membrane and (2) the decreased average localized flux over the membrane surface due to the increased effective filtration area for the nanovoid-induced roughness features. The current study provides fundamental insights into the critical role of surface roughness in membrane fouling, which may have important implications for the future development of high-performance antifouling membranes.


Assuntos
Nanopartículas Metálicas , Purificação da Água , Osmose , Nylons , Substâncias Húmicas , Ouro , Membranas Artificiais , Água , Filtração
5.
Environ Sci Technol ; 56(4): 2656-2664, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35113549

RESUMO

Interlayered thin-film nanocomposite (TFNi) membranes have been shown to achieve enhanced water permeance as a result of the gutter effect. Nevertheless, some studies report impaired separation performance after the inclusion of an interlayer. In this study, we resolve the competing mechanisms of water transport in the transverse direction vs that in the normal direction. To enable easy comparison, carbon nanotube (CNT)-incorporated TFNi membranes with an identical polyamide rejection layer but different interlayer thicknesses were investigated. While increasing the thickness of the CNT interlayer facilitates water transport in the transverse direction (therefore improving the gutter effect), it simultaneously increases its hydraulic resistance in the normal direction. An optimal water permeance of 13.0 ± 0.7 L m-2 h-1 bar-1, which was more than doubled over the control membrane of 6.1 ± 0.7 L m-2 h-1 bar-1, was realized at a moderate interlayer thickness, resulting from the trade-off between these two competing mechanisms. In this study, we demonstrate reduced membrane fouling and improved fouling reversibility for a TFNi membrane over its control without an interlayer, which can be attributed to its more uniform water flux distribution. The fundamental mechanisms revealed in this study lay a solid foundation for the future development of TFNi membranes toward enhanced separation properties and antifouling ability.


Assuntos
Incrustação Biológica , Nanotubos de Carbono , Incrustação Biológica/prevenção & controle , Membranas Artificiais , Nylons , Água
6.
Environ Sci Technol ; 56(14): 10279-10288, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35802136

RESUMO

The permeance and selectivity of a reverse osmosis (RO) membrane are governed by its ultrathin polyamide film, yet the growth of this critical film during interfacial polymerization (IP) has not been fully understood. This study investigates the evolution of a polyamide nanofilm at the aqueous/organic interface over time. Despite its thickness remaining largely constant (∼15 nm) for the IP reaction time ranging from 0.5 to 60 min, the density of the polyamide nanofilm increased from 1.25 to 1.36 g cm-3 due to the continued reaction between diffused m-phenylenediamine and dangling acyl chloride groups within the formed polyamide film. This continued growth of the polyamide nanofilm led to a simultaneous increase in its crosslinking degree (from 50.1 to 94.3%) and the healing of nanosized defects, resulting in a greatly enhanced rejection of 99.2% for NaCl without sacrificing water permeance. Using humic acid as a molecular probe for sealing membrane defects, the relative contributions of the increased crosslinking and reduced defects toward better membrane selectivity were resolved, which supports our conceptual model involving both enhanced size exclusion and healed defects. The fundamental insights into the growth mechanisms and the structure-property relationship of the polyamide nanofilm provide crucial guidance for the further development and optimization of high-performance RO membranes.


Assuntos
Nylons , Água , Filtração/métodos , Membranas Artificiais , Polimerização
7.
Environ Sci Technol ; 56(18): 12811-12827, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36048162

RESUMO

Nanofiltration (NF) membranes have been widely applied in many important environmental applications, including water softening, surface/groundwater purification, wastewater treatment, and water reuse. In recent years, a new class of piperazine (PIP)-based NF membranes featuring a crumpled polyamide layer has received considerable attention because of their great potential for achieving dramatic improvements in membrane separation performance. Since the report of novel crumpled Turing structures that exhibited an order of magnitude enhancement in water permeance ( Science 2018, 360 (6388), 518-521), the number of published research papers on this emerging topic has grown exponentially to approximately 200. In this critical review, we provide a systematic framework to classify the crumpled NF morphologies. The fundamental mechanisms and fabrication methods involved in the formation of these crumpled morphologies are summarized. We then discuss the transport of water and solutes in crumpled NF membranes and how these transport phenomena could simultaneously improve membrane water permeance, selectivity, and antifouling performance. The environmental applications of these emerging NF membranes are highlighted, and future research opportunities/needs are identified. The fundamental insights in this review provide critical guidance on the further development of high-performance NF membranes tailored for a wide range of environmental applications.


Assuntos
Filtração , Nylons , Membranas Artificiais , Nylons/química , Piperazinas , Água
8.
Curr Issues Mol Biol ; 32: 167-200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166172

RESUMO

Streptococcus mutans is considered the predominant etiological agent of dental caries with the ability to form biofilm on the tooth surface. And, its abilities to obtain nutrients and metabolize fermentable dietary carbohydrates to produce acids contribute to its pathogenicity. The responses of S. mutans to environmental stresses are essential for its survival and role in cariogenesis. The VicRK system is one of the 13 putative TCS of S. mutans. The conserved functions of the VicRK signal transduction system is the key regulator of bacterial oxidative stress responses, acidification, cell wall metabolism, and biofilm formation. In this paper, it was discussed how the VicRK system regulates S. mutans virulence including bacterial physiological function, operon structure, signal transduction, and even post-transcriptional control in its regulon. Thus, this emerging subspecialty of the VicRK regulatory networks in S. mutans may strengthen our understandings aimed at providing a basis for the prevention of dental caries.


Assuntos
Proteínas de Bactérias/genética , Cárie Dentária/microbiologia , Regulação Bacteriana da Expressão Gênica , Infecções Estreptocócicas/microbiologia , Streptococcus mutans/genética , Streptococcus mutans/patogenicidade , Adaptação Fisiológica , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Parede Celular/genética , Parede Celular/metabolismo , Cárie Dentária/metabolismo , Cárie Dentária/patologia , Carboidratos da Dieta/metabolismo , Redes Reguladoras de Genes , Humanos , Óperon , Estresse Oxidativo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Regulon , Transdução de Sinais , Infecções Estreptocócicas/metabolismo , Infecções Estreptocócicas/patologia , Streptococcus mutans/metabolismo , Virulência
9.
ACS Appl Mater Interfaces ; 15(39): 45658-45667, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37729093

RESUMO

Platelet transfusion is essential in the treatment of platelet-related diseases and the prevention of bleeding in patients with surgical procedures. Platelet transfusion efficacy and shelf life are limited mainly by the development of platelet storage lesion (PSL). Mitigating PSL is the key to prolonging the platelet shelf life and reducing wastage. Excess intracellular reactive oxygen species (ROS) are one of the main factors causing PSL. In this study, we explored a nanomedicine strategy to improve the quality and functions of platelets in storage. Resveratrol (Res), a natural plant product, is known for its antioxidative effect. However, medical applications of Res are limited due to its low water solubility and stability. Therefore, we used a resveratrol-loaded liposomal system (Res-Lipo) to better utilize the antioxidant effect of the drug. This study aimed to evaluate the effect of Res-Lipo on platelet oxidative stress and alleviation of PSL during the storage time. Res-Lipo scavenged intracellular ROS and inhibited platelet apoptosis and activation during storage. Res-Lipo not only maintained mitochondrial function but also improved platelet aggregation in response to adenosine 5'-diphosphate. These results revealed that Res-Lipo ameliorated PSL and prolonged the platelet survival time in vivo. The strategy provides a potential method for extending the platelet storage time and might be considered a potential and safe additive to alleviate PSL.


Assuntos
Antioxidantes , Plaquetas , Humanos , Antioxidantes/farmacologia , Resveratrol/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Agregação Plaquetária , Lipossomos/farmacologia
10.
Water Res ; 242: 120255, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356158

RESUMO

The existence of disinfection by-products such as haloacetic acids (HAAs) in drinking water severely threatens water safety and public health. Nanofiltration (NF) is a promising strategy to remove HAAs for clean water production. However, NF often possesses overhigh rejection of essential minerals such as calcium. Herein, we developed highly selective NF membranes with tailored surface charge and pore size for efficient rejection of HAAs and high passage of minerals. The NF membranes were fabricated through interfacial polymerization (IP) with NaHCO3 as an additive. The NaHCO3-tailored NF membranes exhibited high water permeance up to ∼24.0 L m - 2 h - 1 bar-1 (more than doubled compared with the control membrane) thanks to the formation of stripe-like features and enlarged pore size. Meanwhile, the tailored membranes showed enhanced negative charge, which benefitted their rejection of HAAs and passage of Ca and Mg. The higher rejection of HAAs (e.g., > 90%) with the lower rejection of minerals (e.g., < 30% for Ca) allowed the NF membranes to achieve higher minerals/HAAs selectivity, which was significantly higher than those of commercially available NF membranes. The simultaneously enhanced membrane performance and higher minerals/HAAs selectivity would greatly boost water production efficiency and water quality. Our findings provide a novel insight to tailor the minerals/micropollutants selectivity of NF membranes for highly selective separation in membrane-based water treatment.


Assuntos
Água Potável , Purificação da Água , Membranas Artificiais , Desinfecção , Cálcio
11.
Front Bioeng Biotechnol ; 10: 965248, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36394023

RESUMO

Background: Hydrophilic dental implants are gaining increasing interest for their ability to accelerate bone formation. However, commercially available hydrophilic implants, such as SLActive™, have some major limitations due to their time-dependent biological aging and lower cost-effectiveness. The non-thermal atmospheric plasma (NTAP) treatment is a reliable way to gain a hydrophilic surface and enhance osseointegration. However, a few studies have been carried out to compare the osseointegration of NTAP-functionalized titanium implants and commercially available hydrophilic implants. Purpose: In this study, we compare the osseointegration abilities of the NTAP-functionalized titanium implant and Straumann SLActive. Material and methods: The NTAP effectiveness was examined using in vitro cell experiments. Then, six beagle dogs were included in the in vivo experiment. Straumann SLActive implants, SLA implants, and SLA implants treated with NTAP were implanted in the mandibular premolar area of dogs. After 2 w, 4 w, and 8 w, the animals were sacrificed and specimens were collected. Radiographic and histological analyses were used to measure osseointegration. Results: NTAP treatment accelerated the initial attachment and differentiation of MC3T3-E1 cells. In the in vivo experiment, bone parameters (e.g., BIC value and BV/TV) and volume of new bone of NTAP groups were close to those of the SLActive group. Additionally, although there was no statistical difference, the osseointegration of SLActive and NTAP groups was evidently superior to that of the SLA group. Conclusion: NTAP-functionalized implants enhanced cell interaction with material and subsequent bone formation. The osseointegration of the NTAP-functionalized implant was comparable to that of the SLActive implant at the early osseointegration stage.

12.
Ann Transl Med ; 9(23): 1746, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35071440

RESUMO

Ameloblastic carcinoma (AC) is an extremely rare malignant odontogenic tumor. The mean age of occurrence for all 141 AC cases analyzed in our systematic review study was 43.59±19.51 years. Males were more affected than females, and the mandible was predominantly affected compared with the maxilla. The main clinical manifestation was a painful or painless swelling with ulceration and radiographic features usually displayed as mixed cystic or solid changes. Surgical resection was the first recommended method of management. Fourteen cases had cervical lymph node spread, 19 had distant metastasis (most commonly in the lung), and 33 had recurrence. We present a rare case of AC involving the maxillary region. Locally extensive surgical resection was carried out. Ablative defects after maxillectomy resulted in the communication of oral cavity and nasal cavity/maxillary antrum and would bring about difficulties in mastication, deglutition, and speech. A submental island flap was applied to close the oronasal and oroantral fistula. The flap and the wounds healed well, with excellent outcomes in terms of appearance, the function of speech, and swallowing on follow up. The submental island flap provides a relatively thin, easy-to-harvest, and well-vascularized tissue, which makes it a reliable option in soft tissue reconstruction of the oral and maxillofacial region.

13.
J Oral Sci ; 63(4): 334-340, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34511587

RESUMO

PURPOSE: In order to promote osseointegration and shorten the healing time after dental implant operations, this study was conducted to develop a chair-side plasma treatment system in which Ti implants were used as a coaxial internal electrode to rapidly enhance their surface hydrophilicity. METHODS: Surface hydrophilicity was evaluated by measurement of the water contact angle and the defined wetting time. Changes in temperature and chemical composition were analyzed using infrared thermal imaging and X-ray photoelectron spectroscopy (XPS), respectively. The biocompatibility of the treated implants was examined in an animal experiment. RESULTS: A marked improvement of hydrophilicity was demonstrated by a decrease in the water contact angle of the treated implant to 0° and wetting of the whole surface within 3 s of water contact. The Ti implant hydrophilization mechanism was explained as a decrease in the degree of hydrocarbon contamination. The surface temperature of the treated implant was close to that of the human body, and good osseointegration was observed in the in vivo experiment. CONCLUSION: The plasma treatment system developed here is a promising chair-side procedure for rapidly enhancing the surface hydrophilicity of Ti implants in clinical operations without any need to consider the degradation of hydrophilicity caused by long-term storage.


Assuntos
Implantes Dentários , Titânio , Animais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Osseointegração , Propriedades de Superfície
14.
J Mater Sci Mater Med ; 21(9): 2673-81, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20535631

RESUMO

The aim of present study is to conceive a biodegradable poly(ethylene glycol)-polylactide (PEG-PLA) copolymer nanoparticle which can be surface biofunctionalized with ligands via biotin-avidin interactions and used as a potential drug delivery carrier targeting to brain glioma in vivo. For this aim, a new method was employed to synthesize biotinylated PEG-PLA copolymers, i.e., esterification of PEG with biotinyl chloride followed by copolymerization of hetero-biotinylated PEG with lactide. PEG-PLA nanoparticles bearing biotin groups on surface were prepared by nanoprecipitation technique and the functional protein transferrin (Tf) were coupled to the nanoparticles by taking advantage of the strong biotin-avidin complex formation. The flow cytometer measurement demonstrated the targeting ability of the nanoparticles to tumor cells in vitro, and the fluorescence microscopy observation of brain sections from C6 glioma tumor-bearing rat model gave the intuitive proof that Tf functionalized PEG-PLA nanoparticles could penetrate into tumor in vivo.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Ácido Láctico/química , Micelas , Polietilenoglicóis/química , Transferrina/química , Humanos
15.
J Biomed Nanotechnol ; 14(2): 294-303, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352925

RESUMO

Bone defects represent a clinical challenge that severely impacts the quality of life of affected patients. To match the shape of a bone defect area exactly, additive manufacturing has emerged as a promising technology to produce customized bone regeneration scaffolds for bone defect treatment. In this study, new three-dimensional (3D)-printed poly(L-lactic acid) (PLLA)/hydroxyapatite (HA) composite scaffolds were developed. HA nanoparticles were first modified by a straightforward, economical method. Briefly, HA nanoparticles were modified with dopamine and hexamethylenediamine, and PLLA chains were grafted onto the HA nanoparticles by aminolysis reaction. Then, the PLLA-modified HA nanoparticles were blended with PLLA to form a thermoplastic composite for 3D printing. Due to the high compatibility between the PLLA matrix and PLLA-modified HA nanoparticles, the 3D-printed PLLA/HA scaffolds possess robust mechanical properties and good biocompatibility. This study provides a flexible strategy to fabricate scaffolds for the customized treatment of bone defects.


Assuntos
Nanopartículas , Engenharia Tecidual , Durapatita , Humanos , Poliésteres , Impressão Tridimensional , Qualidade de Vida , Alicerces Teciduais
16.
J Biomed Mater Res B Appl Biomater ; 78(2): 409-16, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16544306

RESUMO

Polyethersulfone (PES) dead-end tubes were fabricated by means of a phase inversion technique, and then were used as scaffolds for artificial lacrimal glands. The wall of the dead-end tubes could allow nutrients such as ascorbic acid, L-tryptophan, and glucose to pass through, but prevents rat IgG from passing through. Lacrimal acinar epithelial cells of Sprague-Dawley rats were cultured in vitro, and cell-associated secretory component was detected with an immunofluorescence technique to identify the acinar cells. The second passage of the cells showed high degree of cellular differentiation, and was used to seed on the PES tubes. The results showed that the PES tube could support the attachment, the growth, and the proliferation of the rat lacrimal acinar cells. Thus, PES is a substrate for the growth of lacrimal acinar cells and may be a useful scaffolding biomaterial for tissue engineering, such as a scaffold for artificial lacrimal glands.


Assuntos
Órgãos Bioartificiais , Células Epiteliais , Aparelho Lacrimal , Polímeros , Sulfonas , Engenharia Tecidual , Animais , Células Cultivadas , Células Epiteliais/ultraestrutura , Aparelho Lacrimal/ultraestrutura , Masculino , Permeabilidade , Ratos , Ratos Sprague-Dawley
17.
Clin Neurol Neurosurg ; 151: 70-72, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27816028

RESUMO

OBJECTIVES: A higher prevalence of diabetes mellitus in classical trigeminal neuralgia patients was observed in few pilot surveys. The study was aimed to investigate whether diabetes mellitus is a predisposing factor for developing trigeminal neuralgia. MATERIALS AND METHODS: Patients with classical trigeminal neuralgia were enrolled in the case study group. The control group consisted of the same number of age- and gender-matched, randomly sampled subjects without trigeminal neuralgia. Characteristics of classical trigeminal neuralgia cases were analyzed. The prevalence of diabetes mellitus in the cases and controls was calculated using the Chi-square test. RESULTS: The onset age ranged from 31 to 93 in 256 patients affected classical trigeminal neuralgia (162 females; 94 males) with a peak age between the fifth and seventh decade; right-side involvement and mandibular branch affliction occurred at a greater frequency. 21.9% patients in the study group was affected by diabetes mellitus compared to 12.9% of controls. The increased prevalence of diabetes mellitus in the trigeminal neuralgia group was statistically significant (P=0.01). CONCLUSIONS: Diabetes is a risk factor to the development of classical trigeminal neuralgia, and nerve damage duing to hyperglycemia might be the linkage to the two diseases. More works should be done to consolidate the correlation and to clarify the underlying mechanism for the positive association which would provide new insight into the pathogenesis of trigeminal neuralgia and may open new therapeutic perspectives.


Assuntos
Diabetes Mellitus , Neuropatias Diabéticas/complicações , Neuralgia do Trigêmeo/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus/epidemiologia , Neuropatias Diabéticas/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Neuralgia do Trigêmeo/epidemiologia
18.
Analyst ; 127(1): 119-24, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11827377

RESUMO

A new fluorophore, N,N-dibenzyl-3,3',5,5'-tetramethylbenzidine (NBTMB), was prepared and shown to exhibit significant and analytical usefulness for optical sensing toward 2,4-dinitrophenol or 2,4,6-trinitrophenol (picric acid) when it was immobilized in a plasticized poly(vinyl chloride) (PVC) membrane. When the membrane was applied to aqueous nitrophenol solution, NBTMB was able to extract selectively nitrophenol into the membrane phase. Since the extraction equilibrium was accompanied by fluorescence quenching of NBTMB, the chemical recognition process could be directly translated into an optical signal. The sensor showed reversible response in the concentration range from 2.0 x 10(-7) to 6.0 x 10(-5) mol L(-1) for the detection of 2,4-dinitrophenol in NaOAc-HOAc buffer at pH 4.0. It also showed a fast response time (t95% < 1.5 min) when the sensor was applied to 2,4-dinitrophenol solution at concentration levels of 5.26 x 10(-6) and 2.10 x 10(-5) mol L(-1) alternatively. A working principle is proposed and the responses of this sensor to various kinds of nitrophenol were studied. The sensor was applied to the direct determination of 2,4-dinitrophenol in prepared water samples and the indirect assay of the drug cinchonine and the results obtained were satisfactory.


Assuntos
Poluentes Ambientais/análise , Membranas Artificiais , Nitrofenóis/análise , 2,4-Dinitrofenol/análise , Alcaloides de Cinchona/análise , Cloreto de Polivinila , Espectrofotometria
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