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1.
Talanta ; 233: 122568, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215064

RESUMO

Proteomics of human tissues and isolated cellular subpopulations create new opportunities for therapy and monitoring of a patients' treatment in the clinic. Important considerations in such analysis include recovery of adequate amounts of protein for analysis and reproducibility in sample collection. In this study we compared several protocols for proteomic sample preparation: i) filter-aided sample preparation (FASP), ii) in-solution digestion (ISD) and iii) a pressure-assisted digestion (PCT) method. PCT method is known for already a decade [1], however it is not widely used in proteomic research. We assessed protocols for proteome profiling of isolated immune cell subsets and formalin-fixed paraffin embedded (FFPE) tissue samples. Our results show that the ISD method has very good efficiency of protein and peptide identification from the whole proteome, while the FASP method is particularly effective in identification of membrane proteins. Pressure-assisted digestion methods generally provide lower numbers of protein/peptide identifications, but have gained in popularity due to their shorter digestion time making them considerably faster than for ISD or FASP. Furthermore, PCT does not result in substantial sample loss when applied to samples of 50 000 cells. Analysis of FFPE tissues shows comparable results. ISD method similarly yields the highest number of identifications. Furthermore, proteins isolated from FFPE samples show a significant reduction of cleavages at lysine sites due to chemical modifications with formaldehyde-such as methylation (+14 Da) being among the most common. The data we present will be helpful for making decisions about the robust preparation of clinical samples for biomarker discovery and studies on pathomechanisms of various diseases.


Assuntos
Proteoma , Proteômica , Digestão , Formaldeído , Humanos , Inclusão em Parafina , Reprodutibilidade dos Testes
2.
Artigo em Inglês | MEDLINE | ID: mdl-34208312

RESUMO

Knowledge, beliefs, and practices regarding infectious diseases are key elements that ensure practitioners' health and safety. It is important to carry out such a survey in hotels. This study aims to determine the levels of knowledge, beliefs, and practices regarding infectious diseases among practitioners and their associations with the environmental quality of hotels in Wuhan, China. We surveyed infectious disease knowledge, beliefs, and practices of practitioners in 18 hotels and detected these hotels' environment, including physical factors of temperature, humidity, noise, and the indoor air quality of benzene, toluene, xylene, formaldehyde, CO, CO2, the total count of fungi, aerobic plate count, PM10, and PM2.5. 128 practitioners were included, and 28.9% were male. The questionnaire included knowledge, beliefs, and practices regarding infectious diseases. Our study found moderate levels of knowledge and beliefs, and good health practices. People's beliefs toward COVID-19 were correlated significantly with their knowledge (p < 0.05). Beliefs and health practices were correlated significantly with environmental quality (p < 0.05). However, the environmental quality was correlated negatively with the classification of hotels. Conclusively, despite the good health practices of practitioners, the knowledge and beliefs toward infectious diseases need to strengthen. Hotels should emphasize health education in practitioners and the improvement of environmental hygiene. Integrating all three components into a comprehensive environmental promotion program is warranted.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Doenças Transmissíveis , Poluição do Ar em Ambientes Fechados/análise , China , Formaldeído , Humanos , Masculino , SARS-CoV-2
3.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204472

RESUMO

The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure; the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs; diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration.


Assuntos
Lactonas/isolamento & purificação , Lactonas/farmacologia , Struthioniformes/metabolismo , Administração Oral , Administração Tópica , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Diclofenaco/administração & dosagem , Diclofenaco/farmacologia , Edema/tratamento farmacológico , Emulsões/farmacologia , Formaldeído/efeitos adversos , Ibuprofeno/administração & dosagem , Ibuprofeno/farmacologia , Masculino , Paleógnatas/metabolismo , Ratos , Ratos Wistar , Pele/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-34205009

RESUMO

Extensive scholarship has demonstrated that communities of color, low-income communities, and Indigenous communities face greater environmental and health hazards compared to communities with more White or affluent people. Low-income, Indigenous, Black, and/or other populations of color are also more likely to lack access to health care facilities, healthy food, and adequate formal education opportunities. Despite the mountains of evidence that demonstrate the existence and significance of the elevated toxic social and environmental exposures experienced by these communities, the inclusion of these factors into chemical evaluations has been scarce. In this paper, we demonstrate a process built with publicly available data and simple geospatial techniques that could be utilized by the U.S. Environmental Protection Agency (USEPA) to incorporate cumulative approaches into risk assessments under the Toxic Substances Control Act. The use of these approaches, particularly as they relate to identifying potentially exposed and susceptible subpopulations, would help USEPA develop appropriate risk estimates and mitigation strategies to protect disproportionately burdened populations from the adverse effects of chemical exposures. By utilizing such approaches to inform risk evaluation and mitigation, USEPA can identify and protect those most burdened and impacted by toxic chemicals, and finally begin to close the gap of environmental health inequities.


Assuntos
Exposição Ambiental , Saúde Ambiental , Formaldeído , Substâncias Perigosas/toxicidade , Humanos , Medição de Risco , Estados Unidos , United States Environmental Protection Agency
5.
J Agric Food Chem ; 69(26): 7303-7312, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160203

RESUMO

Formaldehyde (HCHO) pollution is a scientific problem of general concern and has aroused wide attention. In this work, a fluorometric method for sensitive detection of formaldehyde was developed based on the oxidase-mimicking activity of MnO2 nanosheets in the presence of o-phenylenediamine (OPD). The MnO2 nanosheets were prepared by the bottom-up approach using manganese salt as the precursor, followed by the exfoliation with bovine serum albumin. The as-prepared MnO2 nanosheets displayed excellent oxidase-mimicking activity, and can be used as the nanoplatform for sensing in fluorometric analysis. OPD was used as a typical substrate because MnO2 nanosheets can catalyze the oxidation of OPD to generate yellow 2,3-diaminophenazine (DAP), which can emit bright yellow fluorescence at the wavelength of 560 nm. While in the presence of formaldehyde, the fluorescence was greatly quenched because formaldehyde can react with OPD to form Schiff bases that decreased the oxidation reaction of OPD to DAP. The main mechanism and the selectivity of the platform were studied. As a result, formaldehyde can be sensitively detected in a wide linear range of 0.8-100 µM with the detection limit as low as 6.2 × 10-8 M. The platform can be used for the detection of formaldehyde in air, beer, and various food samples with good performance. This work not only expands the application of MnO2 nanosheets in fluorescence sensing, but also provides a sensitive and selective method for the detection of formaldehyde in various samples via a new mechanism.


Assuntos
Compostos de Manganês , Oxirredutases , Catálise , Formaldeído , Óxidos
6.
Int J Biol Macromol ; 183: 2293-2304, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34097967

RESUMO

In this work, the synthesis of crosslinked chitosan hydrogels was performed by ionic and covalent interactions using tripolyphosphate (TPP) and formaldehyde (CH2O), respectively. The hydrogels synthesis was performed using a D-Optimal combined experiment design with two mixing variables, A and B representing the TPP weight fraction (slack variable) and CH2O weight fraction, respectively, and three (3) process variables C-chitosan concentration, D-cross-linker concentration, and E-Contact time. The response variables studied were the point of zero charge (pHPZC), the swelling ratio (SW), and the equilibrium water content (EWC), which are relevant physicochemical properties in applications such as the pollutant removal from water. According to the ANOVA results, the model obtained was significant; this means it can be adequately used to predicting pHPZC, SW, and EWC from the mixing and process variables, obtaining coefficients of determination R2 of 0.9572, 0.8900, and 0.8447, respectively. The pHPZC is affected by chitosan concentration, while the crosslinker concentration influences the SW, and the contact time most significantly affected the EWC. Morphology and hardness tests, thermal stability, infrared spectroscopy, and scanning electron microscopy, allowed verifying the types of crosslinking of chitosan with TPP and CH2O.


Assuntos
Quitosana/química , Reagentes para Ligações Cruzadas/química , Formaldeído/química , Polifosfatos/química , Dureza , Hidrogéis , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Propriedades de Superfície , Temperatura , Fatores de Tempo
7.
Environ Sci Technol ; 55(13): 9255-9265, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34101438

RESUMO

This work reports the incorporation of mixed-metal oxides (MMOs) such as Si/Ti and Si/Zr into latex paints in the form of thin coatings for permanent trapping of indoor formaldehyde. The formaldehyde removal performance of the surface coatings was evaluated in a lab-scale indoor air chamber, and the results were compared with those of powder analogues. Due to the pore blockage by the latex, the incorporation led to 6-30% reduction in adsorption capacity and 50-70% drop in the adsorption rate for MMO-latex paints relative to their powder MMO analogues. Under the operating conditions of concentration, temperature, and relative humidity, the Si/Zr-latex paints outperformed the Si/Ti counterparts. It was also observed that performance could decrease over excessive loading, for example, Si/Zr-latex paint with 15/1 Si/Zr weight ratio showed a 20% lower adsorption capacity than that of the Si/Zr-latex paint with 25/1 Si/Zr ratio at 5 ppmv, 25 °C, and 70% RH. While high temperature greatly reduced the adsorption rate of the MMO-latex paints, high humidity slightly promoted the rate of formaldehyde capture. In 10 L, flow-through chamber tests, 25Si/Zr-latex paint reduced 5 ppmv formaldehyde by up to 60% at 25 °C and 70% RH with an adsorption rate of 0.34 ppmv/h. Overall, this study highlights the potential of MMO-latex paints with optimized formation for the efficient abatement of indoor aldehydes.


Assuntos
Poluição do Ar em Ambientes Fechados , Látex , Poluição do Ar em Ambientes Fechados/análise , Formaldeído/análise , Óxidos , Pintura
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 119984, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087772

RESUMO

An innovative and sensitive spectrofluorimetric method has been developed for determination of 6-aminocaproic acid (ACA) in its pure form and its laboratory prepared tablets. The aim of this method is the reaction of ethyl acetoacetate and formaldehyde with the primary amino group presented in ACA as aimed in the Hantzsch reaction, this reaction resulted in formation of a yellow fluorescent dihydropyridine derivative that can be easily detected spectrofluorimetrically at 438 nm (excitation at 358 nm). At the optimum conditions of the reaction, the linear range was found to be (0.7-3.5 µg\mL) with limit of detection is 0.231 µg\mL and limit of quantitation is 0.700 µg\mL. The proposed method used for detection of ACA laboratory prepared tablets with average percentage 100.721 ±â€¯0.701% without any interference from any excipients. This method used for in vitro determination of ACA in spiked human plasma with a percent mean recovery 99.874 ±â€¯1.416%. In addition, the developed method used for determination of ACA in spiked human urine with percent mean recovery 100.314 ±â€¯1.793%.


Assuntos
Ácido Aminocaproico , Formaldeído , Excipientes , Humanos , Espectrometria de Fluorescência , Comprimidos
9.
Artigo em Inglês | MEDLINE | ID: mdl-34063851

RESUMO

Underground shopping districts (USDs) are susceptible to severe indoor air pollution, which can adversely impact human health. We measured 24 volatile organic compounds (VOCs) in 13 USDs throughout South Korea from July to October 2017, and the human risk of inhaling hazardous substances was evaluated. The sum of the concentrations of the 24 VOCs was much higher inside the USDs than in the open air. Based on factor analysis, six indoor air pollution sources were identified. Despite the expectation of a partial outdoor effect, the impacts of the indoor emissions were significant, resulting in an indoor/outdoor (I/O) ratio of 5.9 and indicating elevated indoor air pollution. However, the effects of indoor emissions decreased, and the contributions of the pollution sources reduced when the USD entrances were open and the stores were closed. Although benzene, formaldehyde, and acetaldehyde exhibited lower concentrations compared to previous studies, they still posed health risks in both indoor and outdoor settings. Particularly, while the indoor excess cancer risk (ECR) of formaldehyde was ~10 times higher than its outdoor ECR, benzene had a low I/O ratio (1.1) and a similar ECR value. Therefore, indoor VOC concentrations could be reduced by managing inputs of open air into USDs.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Formaldeído/análise , Humanos , República da Coreia , Compostos Orgânicos Voláteis/análise
10.
Environ Sci Technol ; 55(12): 8341-8350, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34076409

RESUMO

Defective MIL-88B(Fe) nanorods are exploited as exemplary iron-bearing metal-organic framework (MOF) catalyst for molecular oxygen (O2) activation at ambient temperature, triggering effective catalytic oxidation of formaldehyde (HCHO), one of the major indoor air pollutants. Defective MIL-88B(Fe) nanorods, growing along the [001] direction, expose abundant coordinatively unsaturated Fe-sites (Fe-CUSs) along extended hexagonal channels with a diameter of ca. 5 Å, larger enough for the diffusion of O2 (3.46 Å) and HCHO (2.7 Å). The Lewis acid-base interaction between Fe-CUSs and accessible HCHO accelerates the FeIII/FeII cycle, catalyzing Fenton-like O2 activation to produce reactive oxidative species (ROSs), including superoxide radicals (•O2-), hydroxyl radicals (•OH), and singlet oxygen (1O2). Consequently, adsorbed HCHO can be oxidized into CO2 with a considerable mineralization efficiency (over 80%) and exceptional recyclability (4 runs, 48 h). Dioxymethylene (CH2OO), formate (HCOO-) species, and formyl radicals (•CHO) are recorded as the main reaction intermediates during HCHO oxidation. HCHO, H2O, and O2 are captured and activated by abundant FeIII/FeII-CUSs as acid/base and redox sites, triggering synergetic ROS generation and HCHO oxidation, involving cooperative acid-base and redox catalysis processes. This study will bring new insights into exploiting novel MOF catalysts for efficient O2 activation and reliable indoor air purification at ambient temperature.


Assuntos
Compostos Férricos , Nanotubos , Catálise , Formaldeído , Dietilamida do Ácido Lisérgico/análogos & derivados , Oxirredução , Oxigênio , Temperatura
11.
Anal Chim Acta ; 1170: 338654, 2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34090585

RESUMO

A new colorimetric sensor array based on mixing of Molybdenum disulfide quantum dots (MoS2 QDs) and organic reagents is introduced in this study. MoS2 QDs shows a specific and higher affinity to oxygen functionalized volatile compounds like aldehydes and ketones. Therefore, this designed sensor array is used for classification of eight different aldehydes and ketones based on Linear Discriminate Analysis (LDA) at first. The classification accuracy of 96% and 83% was obtained for training and prediction phases, respectively. Then the introduced colorimetric sensor array is used for the semi-quantitative and quantitative analysis of formaldehyde in milk samples. Formaldehyde is an adulteration that is added to the milk for increasing the storage time. Cow milk samples were provided directly from dairy farmer and from supermarkets and were spiked by formaldehyde in the concentration range of 1-25 ppm. The response of sensor array to these samples were analyzed by partial least squares regression (PLS-R) method and were calibrated for concentration of formaldehyde. The PLSR results (R2 = 0.94 and RMSEC = 2.36) shows that proposed sensor is useable in direct analysis of formaldehyde in milk as a complex matrix.


Assuntos
Pontos Quânticos , Aldeídos , Animais , Nariz Eletrônico , Formaldeído , Indicadores e Reagentes , Cetonas , Leite , Molibdênio
12.
BMC Surg ; 21(1): 295, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140024

RESUMO

PURPOSE: To investigate the urogenital fascia (UGF) anatomy in the inguinal region, to provide anatomical guidance for laparoscopic inguinal hernia repair (LIHR). METHODS: The anatomy was performed on 10 formalin-fixed cadavers. The peritoneum and its deeper fascial tissues were carefully dissected. RESULTS: The UGF's bilateral superficial layer extended and ended in front of the abdominal aorta. At the posterior axillary line, the superficial layer medially reversed, with extension represented the UGF's deep layer. The UGF's bilateral deep layer medially extended beside the vertebral body and then continued with the transversalis fascia. The ureters, genital vessels, and superior hypogastric plexus moved between both layers. The vas deferens and spermatic vessels, ensheathed by both layers, moved through the deep inguinal ring. From the deep inguinal ring to the midline, the superficial layer extended to the urinary bladder's posterior wall, whereas the deep layer extended to its anterior wall. Both layers ensheathed the urinary bladder and extended along the medial umbilical ligament to the umbilicus and in the sacral promontory, extended along the sacrum, forming the presacral fascia. The superficial layer formed the rectosacral fascia at S4 sacral vertebra, and the deep layer extended to the pelvic diaphragm, terminating at the levator ani muscle. CONCLUSION: The UGF ensheaths the kidneys, ureters, vas deferens, genital vessels, superior hypogastric plexus, seminal vesicles, prostate, and urinary bladder. This knowledge of the UGF's anatomy in the inguinal region will help find correct LIHR targets and reduce bleeding and other complications.


Assuntos
Hérnia Inguinal , Laparoscopia , Fáscia , Formaldeído , Virilha , Hérnia Inguinal/cirurgia , Humanos , Masculino
13.
Artigo em Inglês | MEDLINE | ID: mdl-33952112

RESUMO

The scope of this work is the evaluation of the non-carcinogenic occupational risk related to foundry emissions, focusing on the category of workers involved in olfactometric assessments. Odor pollution from industrial activities such as foundries is a serious environmental concern. Sensorial techniques (e.g. dynamic olfactometry, EN13725:2003) currently represent the preferred method for odor emission characterization. During olfactometric analyses, human assessors are directly exposed to the odor at increasing concentrations, thus requiring the assessment of the associated exposure risk to guarantee workers' safety. This paper presents an investigation aiming to produce an inventory of compounds emitted from foundries together with their odor thresholds and toxicological limits (TLVs), with the final objective to propose a procedure for ensuring workers' safety during olfactometric analyses. Looking at the database resulting from this study, among the >100 compounds emitted by foundries, 8 have a maximum concentration above their TLV. Among those, ammonia, H2S, phenol, toluene and trimethylamine, produce an odor stimulus before they reach a toxic concentration, thus not representing a risk for olfactometric workers. Benzene, formaldehyde and SO2 are identified as the most critical compounds because they may reach toxic concentrations in foundry emissions, and they start being perceived by humans above their TLV. The proposed procedure entails a minimum dilution factor of 27'000 to be applied to odor samples analyzed by olfactometry, which however might result inapplicable in practical cases, thus pointing out the necessity to adopt chemical measurements to investigate specifically the concentration of the most critical compounds identified in this study.


Assuntos
Exposição Ocupacional/análise , Odorantes/análise , Olfatometria/métodos , Poluentes Atmosféricos/análise , Formaldeído/análise , Humanos , Metalurgia , Tolueno/análise
14.
Environ Res ; 199: 111395, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34048749

RESUMO

Formaldehyde (FA) is a naturally-occurring compound, produced endogenously in diverse living organisms. It also occurs widely in the environment due to anthropogenic (e.g. used as a chemical intermediate) and natural sources (e.g. a component of the volatile organic compounds blends emitted by plants). While FA is considered a potential carcinogen, living organisms have the ability to cope with FA, and some minimum endogenous levels of FA may be required for health. Recently, genetic engineering approaches transferring biological information from one organism to another led to increased assimilation of and conferred genetic-based tolerance to FA in plants-microorganisms systems. Here, we propose that FA commonly induces hormesis, a hypothesis that we confirm by collating evidence from various published studies with animals, plants, and microorganisms. The stimulation by low doses below the no-observed-adverse-effect-level (NOAEL) was modest in magnitude, in agreement with the general hormesis literature. In plants, among the endpoints showing hormesis were growth, lipid peroxidation, and photosynthetic pigments. In various animal cells, hormesis was observed in cell proliferation and viability, responses that were related to mechanisms, such as activation of phosphorylated ERK (extra-cellular signaling-regulated kinase) expression, acceleration of the process of cell division, and enhancement of the Warburg effect (i.e. use of glycolysis by tumor cells to produce energy for rapid growth). Hormetic in vitro responses were reported in several cancerous/tumorous cell lines, suggesting that FA has the potential to influence tumor promotion within a specific concentration range and biological context. These observations suggest that FA commonly acts in an hormetic manner with implications for study designs across a broad range of biological models and in the assessment of environmental and human risks associated with FA exposures.


Assuntos
Hormese , Compostos Orgânicos Voláteis , Animais , Relação Dose-Resposta a Droga , Formaldeído/toxicidade , Humanos , Nível de Efeito Adverso não Observado , Plantas
15.
J Card Surg ; 36(8): 2958-2960, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33938587

RESUMO

A 63-year-old man was admitted to our hospital owing to the shortness of breath. He had undergone ascending aortic repair for acute type-A aortic dissection 14 years ago. In the previous surgery, the primary entry of the ascending aorta had been resected using direct end-to-end anastomosis after transecting the ascending aorta at the level of the entry and gluing the false lumen using a gelatin-resorcin-formalin glue. The anastomosis site on the ascending aorta had been reinforced using Teflon felt strips. The patient developed heart failure owing to severe aortic regurgitation caused by aortic root dilatation. Since the aortic arch was also dilated, he underwent aortic arch and root replacement. The distinctive difficulties experienced during surgery owing to the prior ascending aortic direct repair have been highlighted in this report.


Assuntos
Aneurisma Dissecante , Aneurisma da Aorta Torácica , Aneurisma Dissecante/cirurgia , Aorta/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Formaldeído , Gelatina , Humanos , Masculino , Pessoa de Meia-Idade
16.
Hum Reprod ; 36(7): 1871-1890, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33956944

RESUMO

STUDY QUESTION: Can ovarian tissue morphology be better preserved whilst enabling histological molecular analyses following fixation with a novel fixative, neutral buffered formalin (NBF) with 5% acetic acid (referred to hereafter as Form-Acetic)? SUMMARY ANSWER: Fixation with Form-Acetic improved ovarian tissue histology compared to NBF in multiple species while still enabling histological molecular analyses. WHAT IS KNOWN ALREADY: NBF fixation results in tissue shrinkage in various tissue types including the ovary. Components of ovarian tissue, notably follicles, are particularly susceptible to NBF-induced morphological alterations and can lead to data misrepresentation. Bouin's solution (which contains 5% acetic acid) better preserves tissue architecture compared to NBF but is limited for immunohistochemical analyses. STUDY DESIGN, SIZE, DURATION: A comparison of routinely used fixatives, NBF and Bouin's, and a new fixative, Form-Acetic was carried out. Ovarian tissue was used from three different species: human (n = 5 patients), sheep (n = 3; 6 ovaries; 3 animals per condition) and mouse (n = 14 mice; 3 ovaries from 3 different animals per condition). PARTICIPANTS/MATERIALS, SETTING, METHODS: Ovarian tissue from humans (aged 13 weeks to 32 years), sheep (reproductively young i.e. 3-6 months) and mice (10 weeks old) were obtained and fixed in 2 ml NBF, Bouin's or Form-Acetic for 4, 8, and 24 h at room temperature. Tissues were embedded and sectioned. Five-micron sections were stained with haemotoxylin and eosin (H&E) and the percentage of artefact (clear space as a result of shrinkage) between ovarian structures was calculated. Additional histological staining using Periodic acid-Schiff and Masson's trichrome were performed on 8 and 24 h NBF, Bouin's and Form-Acetic fixed samples to assess the compatibility of the new fixative with stains. On ovarian tissue fixed for both 8 and 24 h in NBF and Form-Acetic, immunohistochemistry (IHC) studies to detect FOXO3a, FoxL2, collagen IV, laminin and anti-Müllerian hormone (AMH) proteins were performed in addition to the terminal deoxynucleotidyl transferase nick end labelling (TUNEL) assay to determine the compatibility of Form-Acetic fixation with types of histological molecular analyses. MAIN RESULTS AND THE ROLE OF CHANCE: Fixation in Form-Acetic improved ovarian tissue morphology compared to NBF from all three species and either slightly improved or was comparable to Bouin's for human, mouse and sheep tissues. Form-Acetic was compatible with H&E, Periodic acid-Schiff and Masson's trichrome staining and all proteins (FOXO3a, FoxL2, collagen IV and laminin and AMH) could be detected via IHC. Furthermore, Form-Acetic, unlike NBF, enabled antigen recognition for most of the proteins tested without the need for antigen retrieval. Form-Acetic also enabled the detection of damaged DNA via the TUNEL assay using fluorescence. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: In this study, IHC analysis was performed on a select number of protein types in ovarian tissue thus encouraging further studies to confirm the use of Form-Acetic in enabling the detection of a wider range of protein forms in addition to other tissue types. WIDER IMPLICATIONS OF THE FINDINGS: The simplicity in preparation of Form-Acetic and its superior preservative properties whilst enabling forms of histological molecular analyses make it a highly valuable tool for studying ovarian tissue. We, therefore, recommend that Form-Acetic replaces currently used fixatives and encourage others to introduce it into their research workflow. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Oxford Medical Research Council Doctoral Training Programme (Oxford MRC-DTP) grant awarded to B.D.B. (Grant no. MR/N013468/1), the Fondation Hoffmann supporting R.A. and the Petroleum Technology Development Fund (PTDF) awarded to B.V.A.


Assuntos
Formaldeído , Ovário , Preservação de Tecido/métodos , Ácido Acético , Animais , Hormônio Antimülleriano , Feminino , Fixadores , Humanos , Imuno-Histoquímica , Camundongos , Ovinos
17.
Curr Protoc ; 1(5): e146, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34033698

RESUMO

Human papillomaviruses (HPVs), specifically high-risk HPVs, are responsible for up to 3% of all cancers in women and up to 2% of all cancers in men. They have been identified as the etiological agent of cervical cancer and have been increasingly found to be the driver behind head and neck cancers of the oropharynx. A system in which we can simultaneously observe transcriptional changes to both a host's tumor microenvironment and its associated oncogenic driver (e.g., HPV) would be highly valuable for understanding HPV's role in tumorigenesis. This article describes a detailed methodology for utilizing high-throughput RNA analysis to study viral transcription in formalin-fixed, paraffin-embedded clinical tumor samples. Although our lab utilizes these methods for the study of head and neck cancer, the principles contained within are widely applicable to all fields of HPV study. © 2021 Wiley Periodicals LLC. Basic Protocol: HPV16 transcript analysis using NanoString Support Protocol 1: Preparation of RNA from formalin-fixed, paraffin-embedded slides Support Protocol 2: Preparation of RNA from cell lysates Support Protocol 3: Fluorometric RNA concentration and RNA integrity analysis Support Protocol 4: Determination of input RNA based on DV300 calculation.


Assuntos
Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Papillomavirus Humano 16/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Transcrição Genética , Microambiente Tumoral/genética , Fluorometria , Formaldeído , Regulação Viral da Expressão Gênica , Humanos , Inclusão em Parafina , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Robótica , Fixação de Tecidos
18.
Work ; 69(1): 209-213, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34024804

RESUMO

BACKGROUND: The safety and health of healthcare workers employed in pathology laboratories and exposed to formaldehyde (FA) is a matter of concern worldwide, as several health effects have been observed in workers resulting from exposure to FA, both short and long-term. OBJECTIVE: The study was aimed to describe the strategy implemented in a hospital pathology laboratory to minimize workers' exposure to FA through interventions to working environment and workforce. METHODS: The NIOSH 2016 method for detecting gaseous FA was adopted to perform personal and area active sampling of FA. The samples were subsequently analyzed by High Performance Liquid Chromatography. The exposure to FA was measured before and after improvement interventions. RESULTS: The pre-intervention step showed FA levels exceeding the threshold limit values (TLV) established by ACGIH, both the time-weighted average (TLV-TWA) and short term exposure limit (TLV-STEL); after the improvement interventions, the median concentrations of personal and area FA sampling were respectively of 0.025 ppm (Range = 0.023-0.027) and 0.023 ppm (Range = 0.022-0.028) and significantly lower than pre-intervention step (p < 0.05) and below the TLV-TWA and TLV-STEL established by ACGIH. CONCLUSIONS: In our study the workers' involvement in the risk management of FA exposure together with engineering improvements revealed a strategic way to minimize the FA pollution in the studied laboratory. Healthcare companies should consider the need to ensure the workers' participation in the management of occupational hazards, including FA, to reach the goal of healthy workplaces.


Assuntos
Laboratórios , Exposição Ocupacional , Formaldeído/efeitos adversos , Hospitais , Humanos , Exposição Ocupacional/prevenção & controle , Hipersensibilidade Respiratória
19.
Arch Oral Biol ; 127: 105136, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34044318

RESUMO

OBJECTIVE: Histological techniques have long been an integral part of dental research. Especially the processing of complex tissues poses specific challenges, however, literature offers only few technical references. Objectives of this study were therefore to optimize histological staining methods and compile detailed protocols for preparation and staining of dental tissues. METHODS: Human teeth were collected and fixed with 4 % formaldehyde solution after extraction. Subsequently, teeth were decalcified in 17 % EDTA or Morse's solution over a period of 28 days. The extent of decalcification was determined by weight loss and radiography. After sectioning, histological staining methods were optimized for their use on teeth. These included hematoxylin-eosin, Masson trichrome, Masson-Goldner trichrome and May-Gruenwald-Giemsa staining. Nerve fibres were visualized by luxol fast blue staining and Bodian silver staining. In addition, specific methods like TRAP, modified Brown and Brenn as well as picrosirius red staining with light polarization or fluorescence were applied and optimized. RESULTS: Preparation of an artificial access to the pulp chamber was essential to ensure prompt penetration of the chemicals. Decalcification with Morse's solution took at least two weeks but was more efficient than 17 % ETDA, where thorough demineralization was achieved only after three weeks. The staining methods exhibited differences not only regarding their ability to display specific structures of interest, but also in terms of reproducibility. CONCLUSION: High-quality histology of teeth can only be achieved after optimal tissue preparation and accurate staining. A complementary use of staining techniques is necessary to answer specific research questions.


Assuntos
Formaldeído , Dente , Técnicas Histológicas , Humanos , Reprodutibilidade dos Testes , Coloração e Rotulagem
20.
Biomacromolecules ; 22(5): 2160-2170, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33884862

RESUMO

It is of particular interest to develop new antibacterial agents with low risk of drug resistance development and low toxicity toward mammalian cells to combat pathogen infections. Although gaseous signaling molecules (GSMs) such as nitric oxide (NO) and formaldehyde (FA) have broad-spectrum antibacterial performance and the low propensity of drug resistance development, many previous studies heavily focused on nanocarriers capable of delivering only one GSM. Herein, we developed a micellar nanoparticle platform that can simultaneously deliver NO and FA under visible light irradiation. An amphiphilic diblock copolymer of poly(ethylene oxide)-b-poly(4-((2-nitro-5-(((2-nitrobenzyl)oxy)methoxy)benzyl)(nitroso)amino)benzyl methacrylate) (PEO-b-PNNBM) was successfully synthesized through atom transfer radical polymerization (ATRP). The resulting diblock copolymer self-assembled into micellar nanoparticles without premature NO and FA leakage, whereas they underwent phototriggered disassembly with the corelease of NO and FA. We showed that the NO- and FA-releasing micellar nanoparticles exhibited a combinatorial antibacterial performance, efficiently killing both Gram-negative (e.g., Escherichia coli) and Gram-positive (e.g., Staphylococcus aureus) bacteria with low toxicity to mammalian cells and low hemolytic property. This work provides new insights into the development of GSM-based antibacterial agents.


Assuntos
Micelas , Óxido Nítrico , Animais , Antibacterianos/farmacologia , Formaldeído , Polímeros
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