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1.
Skin Res Technol ; 27(6): 1035-1042, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34411341

RESUMO

BACKGROUND: The analysis of nail surface topography is a subject of ever-increasing interest in dermatology, especially in cosmetic studies. However, there is no accurate and scientifically sound instrumental method that can identify and provide quantitative data on nail surface topography. MATERIALS AND METHODS: The right index fingers of 78 healthy individuals were examined. The severity of nail roughness was rated by two independent dermatologists on a scale of 1 to 3. Using the phaseshift rapid in vivo measurement of the skin (PRIMOS) system, three-dimensional microtopography was performed, and the roughness parameter values were calculated and evaluated. The relationship between clinical nail roughness grade and nail roughness parameter values obtained utilizing PRIMOS was evaluated. RESULTS: A moderate correlation was found between the roughness parameter values and the clinical roughness grade. Our study showed that an overall relationship exists between the nail roughness parameter values obtained using PRIMOS and clinically observed nail surface changes. CONCLUSION: With further studies, PRIMOS could be a valuable tool for clinicians and researchers for conducting an accurate and objective patient assessment in daily practice and demonstrating effectiveness of different therapies for nail dystrophy or evaluating cosmetic effects of various topical treatments in future clinical trials.


Assuntos
Envelhecimento da Pele , Pele , Administração Tópica , Diagnóstico por Imagem , Humanos , Imageamento Tridimensional , Unhas/diagnóstico por imagem , Pele/diagnóstico por imagem , Propriedades de Superfície
2.
Artigo em Inglês | MEDLINE | ID: mdl-30623747

RESUMO

We investigated the effects of small-scale oscillation (SSO) on toxic Microcystis cells. The oscillating device was made of silicon with two axes that had a diameter of ∼40 mm, and a frequency of 2.5 Hz was observed at 150 rpm. The SSO was effective in inhibiting Microcystis growth. Microcystin release was not observed, whereas cell density barely increased in the oscillating group. Cell size and morphology of the oscillating group were no different from the control group. However, cell quotas of chl.a and microcystin in the oscillating group were half the level of the control group. Crucially, a number of large-sized holes were observed and layered long linear thylakoids were rarely observed in the oscillating group. Therefore, SSO was found to be very effective in Microcystis growth inhibition, and it caused ultrastructural changes without damage to the cell membrane and subsequent microcystin release.


Assuntos
Microcistinas/biossíntese , Microcystis/crescimento & desenvolvimento , Microcystis/ultraestrutura , Clorofila A/metabolismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
3.
Artigo em Inglês | MEDLINE | ID: mdl-26865010

RESUMO

Most of our previous studies reported aluminum causes no cell damage or lysis, and no subsequent toxin release in conventional treatment of drinking water or in the laboratory, on the contrary, we investigated the effect of long-term and large-dose alum treatment, because the environmental conditions in lakes and treatment plants are widely different. The microcosm experiments were designed to simulate the effect of adding alum under the similar conditions of common lakes and reservoirs, and the bottle experiments were conducted to examine the budget or dynamics of microcystin after adding alum. In precipitate analyses, we also confirm the release and dynamics of microcystin and the damage mechanisms of Microcystis cells under alum treatment. In microcosms treated with alum alone, the extracellular microcystin-LR (MC-LR) concentration increased to approximately 82% in 7 days. Similar results were obtained in bottle experiments. By plotting the concentration of released microcystin over time, we inferred that the extracellular MC-LR concentration exponentially rose toward an asymptotic maximum. Moreover, in scanning electron microscope images, some cells exhibited torn membranes with miniscule traces of aluminum hydroxide coating. We conclude that alum treatment, particularly at maximum dosage administered over long periods, seriously damages Microcystis cells and induces microcystin release. Therefore, long-term application of large alum doses is not recommended as an in-lake treatment.


Assuntos
Compostos de Alúmen/toxicidade , Morte Celular/efeitos dos fármacos , Água Potável/química , Lagos/microbiologia , Microcistinas/metabolismo , Microcystis/efeitos dos fármacos , Microcystis/metabolismo , Purificação da Água/métodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-25837559

RESUMO

Electrooxidation is widely used to remove harmful organic and inorganic substances as well as pathogenic microorganisms. This study investigates the removal of Microcystis ichthyoblabe cells and their hepatotoxin microcystin-LR by the electrooxidation process using Pt/Ti electrodes. Additionally, the morphology changes and cell sizes were determined by scanning electron microscopy and a particle size analyzer, respectively. The algal cells were severely damaged by the electrooxidation process. During the initial treatment, intracellular microcystin-LR was released from the cells, increasing the extracellular microcystin-LR concentration. The electrooxidation charge required to remove cells and MC-LR was 3 × 10(4) C and 6 × 10(4) C, respectively. The removal efficiencies of M. ichthyoblabe cells and microcystin-LR were insensitive to initial cell density, initial microcystin-LR concentration and solution conductivity, but were heavily reduced at large algal suspension volume. Therefore, to achieve simultaneous removal of Microcystis cells and their MC, it is necessary to control the volume of algal suspension.


Assuntos
Recuperação e Remediação Ambiental/instrumentação , Substâncias Perigosas/isolamento & purificação , Microcistinas/isolamento & purificação , Microcystis/química , Microcystis/citologia , Desinfecção/métodos , Eletrodos , Recuperação e Remediação Ambiental/métodos , Desenho de Equipamento , Eutrofização , Proliferação Nociva de Algas , Toxinas Marinhas , Oxirredução , Titânio/química , Microbiologia da Água
5.
Environ Technol ; 36(5-8): 983-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25267420

RESUMO

Methane in a simulated biogas converting to methanol under aerobic condition was comparatively assessed by inhibiting the activity of methanol dehydrogenase (MDH) of Methylosinus sporium using phosphate, NaCl, NH4Cl or EDTA in their varying concentrations. The highest amount of methane was indistinguishably diverted at the typical conditions regardless of the types of inhibitors: 35°C and pH 7 under a 0.4% (v/v) of biogas, specifically for <40 mM phosphate, 50 mM NaCl, 40 mM NH4Cl or 150 µM EDTA. The highest level of methanol was obtained for the addition of 40 mM phosphate, 100 mM NaCl, 40 mM NH4Cl or 50 µM EDTA. In other words, 0.71, 0.60, 0.66 and 0.66 mmol methanol was correspondingly generated by the oxidation of 1.3, 0.67, 0.74 and 1.3 mmol methane. It gave a methanol conversion rate of 54.7%, 89.9%, 89.6% and 47.8%, respectively. Among them, the maximum rate of methanol production was observed at 6.25 µmol/mg h for 100 mM NaCl. Regardless of types or concentrations of inhibitors differently used, methanol production could be nonetheless identically maximized when the MDH activity was limitedly hampered by up to 35%.


Assuntos
Oxirredutases do Álcool/antagonistas & inibidores , Metanol/metabolismo , Methylosinus/enzimologia , Cloreto de Amônio/química , Biocombustíveis , Ácido Edético/química , Concentração de Íons de Hidrogênio , Oxirredução , Cloreto de Sódio/química , Temperatura
6.
Ecotoxicol Environ Saf ; 96: 17-23, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23856121

RESUMO

Microcosm and bottle experiments were conducted to evaluate the effects of alum treatment on cyanobacteria-lysing organisms and microcystin-degrading bacteria as well as Microcystis cells, and to provide detailed evidence of Microcystis cell damage by investigating precipitated Microcystis cells. The alum concentration to be pH 6.0 is the maximum which does not cause toxicity by monomeric Al, therefore, this concentration was defined as maximum dose. Microcystis cells were considerably damaged by the alum treatment with maximum dose and long contact time. Seven days post-treatment, intracellular microcystin-LR was released into the extracellular environment in excess of 95 percent and chlorophyll a is not easily released from inside the cell, chl.a of precipitated Microcystis cells was also decreased to approximately 50 percent. Moreover, alum treatment caused damage to cyanobacteria-lysing organisms and microcystin-degrading bacteria, as well as to Microcystis cells. Therefore, it could be concluded that alum treatment with maximum dose (48 mg L(-1) as AI) is not suitable for removing cyanobacterial bloom without the release of cyanotoxin in reservoirs and ponds.


Assuntos
Compostos de Alúmen/toxicidade , Lagos/microbiologia , Bactérias/efeitos dos fármacos , Clorofila/análise , Clorofila/metabolismo , Clorofila A , Cianobactérias/química , Cianobactérias/efeitos dos fármacos , Microcistinas/análise , Microcistinas/metabolismo , Microcystis/efeitos dos fármacos
7.
Artigo em Inglês | MEDLINE | ID: mdl-22217090

RESUMO

1,4-Dioxane is one of the by-products from the polyester manufacturing process, which has been carelessly discharged into water bodies and is a weak human carcinogen. In this study, a laboratory-scale, up-flow biological aerated filter (UBAF), packed with tire chips, was investigated for the treatment of 1,4-dioxane. The UBAF was fed with effluent, containing an average of 31 mg/L of 1,4-dioxane, discharged from an anaerobic treatment unit at H Co. in the Gumi Industrial Complex, South Korea. In the batch, a maximum of 99.5 % 1,4-dioxane was removed from an influent containing 25.6 mg/L. In the continuous mode, the optimal empty bed contact time (EBCT) and air to liquid flow rate (A:L) were 8.5 hours and 30:1, respectively. It was also found that the removal efficiency of 1,4-dioxane increased with increasing loading rate within the range 0.04 to 0.31 kg 1,4-dioxane/m(3)·day. However, as the COD:1,4-dioxane ratio was increased within the range 3 to 46 (mg/L COD)/(mg/L 1,4-dioxane), the removal efficiency unexpectedly decreased.


Assuntos
Bactérias Aeróbias/metabolismo , Reatores Biológicos , Dioxanos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Aerobiose , Bactérias Aeróbias/classificação , Bactérias Aeróbias/genética , Biofilmes/classificação , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Filtração , Resíduos Industriais , Microscopia Eletrônica de Varredura , Oxigênio/análise , Poliésteres , Esgotos/microbiologia
8.
Genes Brain Behav ; 18(5): e12545, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30675754

RESUMO

The mechanosensory neurons of Drosophila larvae are demonstrably activated by diverse mechanical stimuli, but the mechanisms underlying this function are not completely understood. Here we report a genetic, immunohistochemical, and electrophysiological analysis of the Ppk30 ion channel, a member of the Drosophila pickpocket (ppk) family, counterpart of the mammalian Degenerin/Epithelial Na+ Channel family. Ppk30 mutant larvae displayed deficits in proprioceptive movement and mechanical nociception, which are detected by class IV sensory (mdIV) neurons. The same neurons also detect heat nociception, which was not impaired in ppk30 mutant larvae. Similarly, Ppk30 mutation did not alter gentle touch mechanosensation, a distinct mechanosensation detected by other neurons, suggesting that Ppk30 has a functional role in mechanosensation in mdIV neurons. Consistently, Ppk30 was expressed in class IV neurons, but was not detectable in other larval skin sensory neurons. Mutant phenotypes were rescued by expressing Ppk30 in mdIV neurons. Electrophysiological analysis of heterologous cells expressing Ppk30 did not detect mechanosensitive channel activities, but did detect acid-induced currents. These data show that Ppk30 has a role in mechanosensation, but not in thermosensation, in class IV neurons, and possibly has other functions related to acid response.


Assuntos
Proteínas de Drosophila/genética , Nociceptividade , Propriocepção , Canais de Sódio/genética , Potenciais de Ação , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Mecanorreceptores/metabolismo , Mecanorreceptores/fisiologia , Canais de Sódio/metabolismo
9.
J Hazard Mater ; 302: 375-385, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26479190

RESUMO

Arsenic in water and wastewater is considered to be a critical contaminant as it poses harmful health risks. In this regard, to meet the stringent regulation of arsenic in aqueous solutions, nitrogen doped carbon-based materials (CN) were prepared as adsorbents and tested for the removal of arsenic ion from aqueous solutions. Nitrogen-doped carbon (CNs) synthesized by chlorination exhibited well-developed micro- and small meso-pores with uniform pore structures. The structure and characteristics of the adsorbents thus developed were confirmed by field-emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. Among the CNs developed, CN700 exhibited high adsorption capacity for arsenic (31.08 mg/g). The adsorption efficiency for arsenic ion was confirmed to be affected by pyrrolic nitrogen and micro-pores. These results suggest that CNs are useful adsorbents for the treatment of arsenic, and in particular, CN700 demonstrates potential for application as an adsorbent for the removal of anionic heavy metals from wastewater and sewage.

10.
FEMS Immunol Med Microbiol ; 45(2): 341-7, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16019195

RESUMO

Current human anthrax vaccines available in the United States and Europe consist of alum-precipitated supernatant material from cultures of a toxigenic, nonencapsulated strain of Bacillus anthracis. The major component of human anthrax vaccine that confers protection is protective antigen (PA). A second-generation human vaccine using the recombinant PA (rPA) is being developed. In this study, to prevent the toxicity and the degradation of the native rPA by proteases, we constructed two PA variants, delPA (163-168) and delPA (313-314), that lack trypsin (S(163)-R(164)-K(165)-K(166)-R(167)-S(168)) or chymotrypsin cleavage sequence (F(313)-F(314)), respectively. These proteins were expressed in Bacillus brevis 47-5Q. The delPAs were fractionated from the culture supernatant of B. brevis by ammonium sulfate at 70% saturation, followed by anion exchange chromatography on a Hitrap Q, Hiload 16/60 superdex 200 gel filtration column and phenyl sepharose hydrophobic interaction column. In accordance with previous reports, both delPA proteins combined with lethal factor protein did not show any cytotoxicity on J774A.1 cells. The delPA (163-168) and delPA (313-314) formulated either in Rehydragel HPA or MPL-TDM-CWS (Ribi-Trimix), elicited a comparable amount of anti-PA and neutralizing antibodies to those of native rPA in guinea pigs, and confers full protection of guinea pigs from 50xLD50 of fully virulent B. anthracis spore challenges. Ribi-Trimix was significantly more effective in inducing anti-PA and neutralizing antibodies than Rehydragel HPA. These results indicate the possibility of delPA (163-168) and delPA (313-314) proteins being developed into nontoxic, effective and stable recombinant vaccine candidates.


Assuntos
Antígenos de Bactérias/genética , Bacillus anthracis/genética , Bacillus anthracis/imunologia , Toxinas Bacterianas/genética , Sequência de Aminoácidos , Animais , Vacinas contra Antraz/genética , Vacinas contra Antraz/imunologia , Vacinas contra Antraz/isolamento & purificação , Vacinas contra Antraz/toxicidade , Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/isolamento & purificação , Antígenos de Bactérias/toxicidade , Bacillus/genética , Toxinas Bacterianas/imunologia , Toxinas Bacterianas/isolamento & purificação , Toxinas Bacterianas/toxicidade , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , Quimotripsina , DNA Bacteriano/genética , Feminino , Genes Bacterianos , Cobaias , Humanos , Camundongos , Mutação , Testes de Neutralização , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/toxicidade , Deleção de Sequência , Tripsina
11.
Appl Biochem Biotechnol ; 171(6): 1487-99, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23963715

RESUMO

Using a methanotrophic consortium (that includes Methylosinus sporium NCIMB 11126, Methylosinus trichosporium OB3b, and Methylococcus capsulatus Bath) isolated from a landfill site, the potential for partial oxidation of methane into methanol through selective inhibition of methanol dehydrogenase (MDH) over soluble methane monooxygenase (sMMO) with some selected MDH inhibitors at varied concentration range, was evaluated in batch serum bottle and bioreactor experiments. Our result suggests that MDH activity could effectively be inhibited either at 40 mM of phosphate, 100 mM of NaCl, 40 mM of NH4Cl or 50 µM of EDTA with conversion ratios (moles of CH3OH produced per mole CH4 consumed) of 58, 80, 80, and 43 %, respectively. The difference between extent of inhibition in MDH activity and sMMO activity was significantly correlated (n = 6, p < 0.05) with resultant methane to methanol conversion ratio. In bioreactor study with 100 mM of NaCl, a maximum specific methanol production rate of 9 µmol/mg h was detected. A further insight with qPCR analysis of MDH and sMMO coding genes revealed that the gene copy number continued to increase along with biomass during reactor operation irrespective of presence or absence of inhibitor, and differential inhibition among two enzymes was rather the key for methanol production.


Assuntos
Oxirredutases do Álcool/metabolismo , Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Metano/metabolismo , Metanol/metabolismo , Microbiologia do Solo , Oxirredutases do Álcool/genética , Processos Autotróficos , Bactérias/enzimologia , Bactérias/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , Regulação para Baixo , Processos Heterotróficos , Oxirredução , Oxigenases/genética , Oxigenases/metabolismo
12.
Yonsei Med J ; 51(1): 138-40, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20046528

RESUMO

A pathologic splenic rupture refers to a rupture without trauma. A splenic rupture as the initial manifestation of acute myeloid leukemia is extremely rare. In this study, we described a rare case of acute myeloid leukemia presenting principally as an acute abdomen due to a pathologic splenic rupture in a 35-year old male patient. We can assert that a pathologic splenic rupture in hematologic diseases is a potentially life-threatening complication, which necessitates immediate operative intervention. Any such patient complaining about left upper abdominal tenderness should be closely observed, and further diagnostic investigations (ultrasonograph of the abdomen, abdominal CT scan) should be initiated in order to rule out a splenic rupture. The oncologist should be aware of this rare initial presentation of acute myeloid leukemia (AML) M2, as the condition generally necessitates a prompt splenectomy.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Ruptura Esplênica/diagnóstico , Adulto , Humanos , Leucemia Mieloide Aguda/diagnóstico por imagem , Leucemia Mieloide Aguda/patologia , Masculino , Ruptura Esplênica/diagnóstico por imagem , Ruptura Esplênica/patologia , Tomografia Computadorizada por Raios X
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