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1.
Front Cell Infect Microbiol ; 14: 1382508, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828263

RESUMO

Introduction: Sporotrichosis is a subcutaneous mycosis caused by fungi of the genus Sporothrix sp. Phenotypic and genotypic differences have been associated with their geographic distribution, virulence, or clinical manifestation of sporotrichosis. In the past decade, the interest in identifying species of the Sporothrix sp. has been increasing, due to its epidemiological importance and, in consequence, is important to know how to preserve them for future studies, in culture collection. Aims: The purposes of this study were to analyze the global distribution of environmental isolates and/or causal agents of sporotrichosis identified by polyphasic taxonomy, with mandatory use of molecular identification, and to evaluate the percentages and distribution of isolates stored in culture collections. Methods: A systematic review of articles on animal and human sporotrichosis and/or environmental isolation of the fungus, from 2007 to 2023, was done. Results: Our results demonstrated that, S. globosa, S. schenckii, and S. brasiliensis were the most identified species. With respect to the deposit and maintenance of species, we observed that only 17% of the strains of Sporothrix sp. isolated in the world are preserved in a culture collection. Conclusions: This systematic review confirmed a difficulty in obtaining the frequency of Sporothrix species stored in culture collection and insufficient data on the molecular identification mainly of animal sporotrichosis and isolation of Sporothrix sp. in environmental samples.


Assuntos
Sporothrix , Esporotricose , Sporothrix/classificação , Sporothrix/isolamento & purificação , Sporothrix/genética , Esporotricose/microbiologia , Animais , Humanos , Microbiologia Ambiental , Preservação Biológica/métodos
2.
Int. j. morphol ; 41(5): 1281-1287, oct. 2023. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1521045

RESUMO

SUMMARY: Osteotechnics is one of the different anatomical preservation techniques and can be defined as the technique designed to prepare, clean, obtain and preserve bone structures that can be used in the teaching, museographic or research field. The osteotechnical technique procedure consists of the following phases: debulk and disjoint, maceration, cooking, cleaning, degreasing, bleaching, and labeling to obtain bone material. Seven phases will be explained in detail, as well as the materials, instruments, quantities of the substances used, and the time required to obtain human bone material. We consider that this article can serve as a guide, given that all the experimentation was carried out with human biological material. This methodological proposal could be consolidated and established based on the experience acquired during the creation of the contemporary skeletal collection of the department of innovation in human biological material (DIMBIH). Therefore, the purpose of our proposal is to provide tools that facilitate the work of those who carry out this work and fundamentally to avoid irreversible or irreparable damage to the osteological material, since it is of great value and difficult to acquire for disciplines as anatomy, veterinary, physical and forensic anthropology, medicine, dentistry and biology.


La osteotecnia es una de las técnicas diferentes de conservación anatómica y puede definirse como la técnica destinada a preparar, limpiar, obtener y conservar estructuras óseas que pueden ser utilizadas en el ámbito docente, museográfico o de investigación. El procedimiento de la técnica osteotécnica consta de las siguientes fases: descarnado y desarticulado, maceración, cocción, limpieza, desengrase, blanqueo y marcaje para la obtención de material óseo. Se explicarán en detalle siete fases, así como los materiales, instrumentos, cantidades de las sustancias utilizadas y el tiempo necesario para obtener material óseo humano. Consideramos que este artículo puede servir de guía, dado que toda la experimentación se realizó con material biológico humano. Esta propuesta metodológica pudo consolidarse y establecerse a partir de la experiencia adquirida durante la creación de la colección esquelética contemporánea del Departamento de Innovación en Material Biológico Humano (DIMBIH). Por lo tanto, el propósito de nuestra propuesta es brindar herramientas que faciliten el trabajo de quienes realizan este trabajo y fundamentalmente evitar daños irreversibles o irreparables en el material osteológico, ya que es de gran valor y difícil adquisición para las disciplinas como la anatomía, veterinaria, antropología física y forense, medicina, odontología y biología.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Preservação Biológica/métodos , Osso e Ossos , Anatomia/métodos , Antropologia Física , Osteologia
3.
Microbiol Spectr ; 9(3): e0187721, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34908431

RESUMO

A critical step in studies of the intestinal microbiome using meta-omics approaches is the preservation of samples before analysis. Preservation is essential for approaches that measure gene expression, such as metaproteomics, which is used to identify and quantify proteins in microbiomes. Intestinal microbiome samples are typically stored by flash-freezing and storage at -80°C, but some experimental setups do not allow for immediate freezing of samples. In this study, we evaluated methods to preserve fecal microbiome samples for metaproteomics analyses when flash-freezing is not possible. We collected fecal samples from C57BL/6 mice and stored them for 1 and 4 weeks using the following methods: flash-freezing in liquid nitrogen, immersion in RNAlater, immersion in 95% ethanol, immersion in a RNAlater-like buffer, and combinations of these methods. After storage, we extracted protein and prepared peptides for liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis to identify and quantify peptides and proteins. All samples produced highly similar metaproteomes, except for ethanol-preserved samples that were distinct from all other samples in terms of protein identifications and protein abundance profiles. Flash-freezing and RNAlater (or RNAlater-like treatments) produced metaproteomes that differed only slightly, with less than 0.7% of identified proteins differing in abundance. In contrast, ethanol preservation resulted in an average of 9.5% of the identified proteins differing in abundance between ethanol and the other treatments. Our results suggest that preservation at room temperature in RNAlater or an RNAlater-like solution performs as well as freezing for the preservation of intestinal microbiome samples before metaproteomics analyses. IMPORTANCE Metaproteomics is a powerful tool to study the intestinal microbiome. By identifying and quantifying a large number of microbial, dietary, and host proteins in microbiome samples, metaproteomics provides direct evidence of the activities and functions of microbial community members. A critical step for metaproteomics workflows is preserving samples before analysis because protein profiles are susceptible to fast changes in response to changes in environmental conditions (air exposure, temperature changes, etc.). This study evaluated the effects of different preservation treatments on the metaproteomes of intestinal microbiome samples. In contrast to prior work on preservation of fecal samples for metaproteomics analyses, we ensured that all steps of sample preservation were identical so that all differences could be attributed to the preservation method.


Assuntos
Bactérias/isolamento & purificação , Microbioma Gastrointestinal , Preservação Biológica/métodos , Animais , Bactérias/química , Bactérias/genética , Proteínas de Bactérias/química , Cromatografia Líquida , Fezes/química , Fezes/microbiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/química , Proteômica/métodos , Espectrometria de Massas em Tandem
4.
Sci Rep ; 11(1): 13592, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193912

RESUMO

With global demand for SARS-CoV-2 testing ever rising, shortages in commercially available viral transport media pose a serious problem for laboratories and health care providers. For reliable diagnosis of SARS-CoV-2 and other respiratory viruses, executed by Real-time PCR, the quality of respiratory specimens, predominantly determined by transport and storage conditions, is crucial. Therefore, our aim was to explore the reliability of minimal transport media, comprising saline or the CDC recommended Viral Transport Media (HBSS VTM), for the diagnosis of SARS-CoV-2 and other respiratory viruses (influenza A, respiratory syncytial virus, adenovirus, rhinovirus and human metapneumovirus) compared to commercial products, such as the Universal Transport Media (UTM). We question the assumptions, that the choice of medium and temperature for storage and transport affect the accuracy of viral detection by RT-PCR. Both alternatives to the commercial transport medium (UTM), HBSS VTM or saline, allow adequate detection of SARS-CoV-2 and other respiratory viruses, regardless of storage temperatures up to 28 °C and storage times up to 28 days. Our study revealed the high resilience of SARS-CoV-2 and other respiratory viruses, enabling proper detection in clinical specimens even after long-time storage at high temperatures, independent of the transport medium's composition.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Meios de Cultura/química , Preservação Biológica/métodos , SARS-CoV-2/genética , Manejo de Espécimes/métodos , Virologia/métodos , Temperatura Baixa , Humanos , Reagentes de Laboratório/química , Reprodutibilidade dos Testes , Fatores de Tempo
5.
Int J Biol Macromol ; 167: 995-1005, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188812

RESUMO

The aim of this study was to well understand the impacts of innovative drying techniques (radio frequency drying and microwave drying) and traditional drying techniques (vacuum drying, freezing drying, and hot air drying) on the structural characteristics and bioactivities of polysaccharides from dandelion leaves (DLPs). Five different DLPs were obtained from dandelion leaves dried by abovementioned drying techniques. Results showed that the structural characteristics and bioactivities of DLPs varied with different drying techniques. The molecular weights, apparent viscosities, molar ratios of constituent monosaccharide, contents of uronic acids, and contents of bonded polyphenolics in DLPs obtained by different drying techniques had noticeable variations, while the types of constituent monosaccharides and the major glycosidic linkages in DLPs were similar. In addition, results showed that DLPs, especially DLP-RF obtained by the radio frequency drying, exhibited remarkable antioxidant activities (ABTS, DPPH, and NO radical scavenging activities), excellent in vitro antiglycation activity, and obvious in vitro inhibitory activity on α-glucosidase. Results from this study suggest that the radio frequency drying can be used as a potential drying technique before extracting DLPs for applications in the functional food and medicine industries.


Assuntos
Folhas de Planta/química , Polissacarídeos/química , Taraxacum/química , Fracionamento Químico , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Glicosilação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Peso Molecular , Monossacarídeos/química , Preservação Biológica/métodos , Relação Estrutura-Atividade , Viscosidade
6.
PLoS One ; 15(11): e0242522, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211739

RESUMO

Different regions have different environmental conditions, which may be unfavorable for the preservation of the quality of stored soybean seeds over time. Thus, it is necessary to adopt specific technologies to control the storage environment conditions. Big raffia bags are widely used for the storage of soybean seeds, however these consist of a porous, permeable material that allows the exchange of gases between the packaging and the storage environment. In an effort to find a solution to this problem, in this study we evaluated low cost big bag coating alternatives, in order to minimize the effects of temperature and intergranular humidity on stored seeds. Thus, the aim of this work was to evaluate the quality of soybean cultivars subjected to different temperature and storage duration conditions and stored in raffia bags with or without internal coating. We used a completely randomized, three-factor (10 × 6 × 5) experimental design. We assessed 10 soybean cultivars, six storage environments, and five evaluation periods. Our results showed that seeds of the M-SOY 8866, M7110 IPRO, CD 2737 RR, and BMX DESAFIO 8473 RSF soybean cultivars preserved their physiological quality better in different storage environments. The storage duration had a cumulative effect on the negative factors that favor the deterioration of the quality of the stored seeds. The storage temperature was the main factor that affected the physiological quality of the stored seeds. The use of coated packaging was beneficial in preserving the physiological quality of stored soybean seeds; however, its effect was greater at ambient temperature than in a cold environment. The best storage environment for the preservation of the quality of the seeds was characterized by 10°C temperature conditions and the use of coated packaging, while the worst storage environment was characterized by ambient temperature conditions without the use of coated packaging. Thus, it was concluded that the use of coatings in raffia big bags can be an alternative for maintaining the quality of seeds of different soybean cultivars during storage in seed processing units.


Assuntos
Glycine max , Preservação Biológica/métodos , Embalagem de Produtos/instrumentação , Resinas Sintéticas , Banco de Sementes , Sementes , Têxteis , Sobrevivência Celular , Condutividade Elétrica , Germinação , Umidade , Polietileno , Polipropilenos , Preservação Biológica/instrumentação , Distribuição Aleatória , Sementes/química , Sementes/fisiologia , Temperatura , Fatores de Tempo , Água/análise
7.
Curr Protoc Microbiol ; 58(1): e110, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32833351

RESUMO

Vesicular stomatitis virus (VSV) is the prototypical member of the Rhabdoviridae family of negative-sense single-stranded RNA viruses. This virus has been used as a powerful model system for decades and is currently being used as a vaccine platform and an oncolytic agent. Here, we present methods to propagate, quantitate, and store VSV. We also review the proper safety protocol for the handling of VSV, which is classified as a Biosafety Level 2 pathogen by the United States Centers for Disease Control and Prevention. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Generation, purification, and storage of vesicular stomatitis virus stocks Basic Protocol 2: Quantification of vesicular stomatitis virus by plaque assay Support Protocol: Propagation of Vero cells.


Assuntos
Preservação Biológica/métodos , Manejo de Espécimes/métodos , Vírus da Estomatite Vesicular Indiana/crescimento & desenvolvimento , Vírus da Estomatite Vesicular Indiana/isolamento & purificação , Ensaio de Placa Viral/métodos , Cultura de Vírus/métodos , Animais , Linhagem Celular , Chlorocebus aethiops , Humanos , Células Vero , Estomatite Vesicular/virologia
8.
Curr Protoc Microbiol ; 57(1): e102, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32515871

RESUMO

Giardia lamblia is a protozoan parasite that is found ubiquitously throughout the world and is a major contributor to diarrheal disease. Giardia exhibits a biphasic lifestyle existing as either a dormant cyst or a vegetative trophozoite. Infections are typically initiated through the consumption of cyst-contaminated water or food. Giardia was first axenized in the 1970s and can be readily maintained in a laboratory setting. Additionally, Giardia is one of the few protozoans that can be induced to complete its complete lifecycle using laboratory methods. In this article, we outline protocols to maintain Giardia and induce passage through its lifecycle. We also provide protocols for infecting and quantifying parasites in an animal infection model. © 2020 Wiley Periodicals LLC. Basic Protocol 1: In vitro maintenance and growth of Giardia trophozoites Basic Protocol 2: In vitro encystation of Giardia cysts Basic Protocol 3: In vivo infections using Giardia trophozoites.


Assuntos
Técnicas de Cultura de Células/métodos , Giardia lamblia/crescimento & desenvolvimento , Giardíase/parasitologia , Parasitologia/métodos , Preservação Biológica/métodos , Animais , Modelos Animais de Doenças , Giardia lamblia/genética , Giardia lamblia/fisiologia , Humanos , Estágios do Ciclo de Vida , Camundongos , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Trofozoítos/genética , Trofozoítos/crescimento & desenvolvimento , Trofozoítos/fisiologia
9.
Transfusion ; 60(9): 1905-1909, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32583465

RESUMO

New York is at the epicenter of the coronavirus disease 2019 (COVID-19) pandemic caused by the SARS-CoV-2 virus. Columbia University Irving Medical Center/NewYork-Presbyterian Hospital (CUIMC/NYPH) had to make changes to its cellular therapy operations to ensure patient, donor, and staff safety and well-being. In this article, we discuss the process changes we instituted for cellular therapy clinical care, collection, processing, and cryopreservation to cope with the rapidly evolving pandemic.


Assuntos
Centros Médicos Acadêmicos , COVID-19/epidemiologia , Terapia Baseada em Transplante de Células e Tecidos/estatística & dados numéricos , Pandemias , SARS-CoV-2 , Centros Médicos Acadêmicos/organização & administração , Centros Médicos Acadêmicos/estatística & dados numéricos , Adulto , Transplante de Medula Óssea/métodos , Transplante de Medula Óssea/estatística & dados numéricos , Teste para COVID-19 , Separação Celular/métodos , Criança , Ensaios Clínicos como Assunto/organização & administração , Criopreservação/métodos , Seleção do Doador , Humanos , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/estatística & dados numéricos , Transfusão de Linfócitos/métodos , Transfusão de Linfócitos/estatística & dados numéricos , Cidade de Nova Iorque/epidemiologia , Preservação de Órgãos/métodos , Transplante de Células-Tronco de Sangue Periférico/métodos , Transplante de Células-Tronco de Sangue Periférico/estatística & dados numéricos , Preservação Biológica/métodos , Utilização de Procedimentos e Técnicas , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/organização & administração
10.
Sci Adv ; 6(10): eaau4819, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32181330

RESUMO

A novel, thin-film platform that preserves live viruses, bacteria, antibodies, and enzymes without refrigeration for extended periods of time is described. Studies with recombinant adenovirus in an optimized formulation that supports recovery of live virus through 16 freeze-thaw cycles revealed that production of an amorphous solid with a glass transition above room temperature and nitrogen-hydrogen bonding between virus and film components are critical determinants of stability. Administration of live influenza virus in the optimized film by the sublingual and buccal routes induced antibody-mediated immune responses as good as or better than those achieved by intramuscular injection. This work introduces the possibility of improving global access to a variety of medicines by offering a technology capable of reducing costs of production, distribution, and supply chain maintenance.


Assuntos
Adenoviridae/imunologia , Anticorpos Antivirais/biossíntese , Imunização/métodos , Vírus da Influenza A Subtipo H1N1/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Preservação Biológica/métodos , Vacinas Atenuadas/farmacologia , Adenoviridae/genética , Administração Bucal , Administração Sublingual , Animais , Anticorpos Neutralizantes/biossíntese , Células HEK293 , Humanos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Injeções Intramusculares , Masculino , Membranas Artificiais , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Temperatura , Potência de Vacina , Vacinas Atenuadas/biossíntese
11.
Electron. j. biotechnol ; 44: 1-5, Mar. 2020. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1087706

RESUMO

Background: Freeze-drying is known as one of the best methods to preserve bacterial strains. Protectant is the key factor affecting the survival rate of freeze-dried strains. In addition, salinity, bacterial suspension concentration, drying time, and other factors can also affect the survival rate of strains to varying degrees. At present, there are relatively few studies on freeze-drying preservation of marine bacteria. In the present study, we performed the freeze-drying protectant screening and optimized the preservation conditions for Pseudoalteromonas nigrifaciens, which is widely distributed in marine environment. The protective effects of the screened protectants were verified by 18 other marine bacterial strains. Results: The results indicated that the combination of 5.0% (w/v) lactose, 5.0% (w/v) mannitol, 5.0% (w/v) trehalose, 10.0% (w/v) skim milk powder, 0.5% (w/v) ascorbic acid and 0.5% (w/v) gelatin was the best choice for the preservation of P. nigrifaciens. The suggested salinity and concentration of initial cell suspension were 10 g/L NaCl and 1.0 × 109 CFU/mL, respectively. Furthermore, stationary-phase cells were the best choice for the freeze-drying process. The highest survival rate of P. nigrifaciens reached 52.8% when using 5­10% (w/v) skim milk as rehydration medium. Moreover, the other 18 marine strains belonging to Pseudoalteromonas, Vibrio, Photobacterium, Planomicrobium, Edwardsiella, Enterococcus, Bacillus, and Saccharomyces were freezedried under the abovementioned conditions. Their survival rates were 2.3­95.1%. Conclusion: Collectively, our results supported that the protectant mixture and parameters were beneficial for lyophilization of marine bacteria


Assuntos
Preservação Biológica/métodos , Pseudoalteromonas/fisiologia , Liofilização/métodos , Trealose/química , Sobrevivência Celular , Fenômenos Fisiológicos Bacterianos , Dissacarídeos/química , Viabilidade Microbiana , Salinidade , Lactose/química , Manitol/química
12.
Anticancer Res ; 39(12): 6701-6709, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810935

RESUMO

BACKGROUND/AIM: Extracellular vesicles (exosomes, EVs) (30-200 nm in diameter) are secreted by various cells in the body. Owing to the pharmaceutical advantages of EVs, an EV-based drug delivery system (DDS) for cancer therapy is expected to be the next-generation therapeutic system. However, preservation methods for functional and therapeutic EVs should be developed. Here, we developed the method of lyophilization of arginine-rich cell penetrating peptide (CPP)-modified EVs and investigated the effects of lyophilization on the characteristics of EVs. MATERIALS AND METHODS: Particle size, structure, zeta-potential, and cellular uptake efficacy of the arginine-rich CPP-modified EVs were analyzed. The model protein saporin (SAP), having anti-cancer effects, was encapsulated inside the EVs to assess the cytosolic release of EV content after cellular uptake. RESULTS: Lyophilization of the EVs did not affect their particle size, structure, zeta-potential, and cellular uptake efficacy; however, the biological activity of the encapsulated SAP was inhibited by lyophilization. CONCLUSION: Lyophilization of EVs may affect SAP structures and/or reduce the cytosolic release efficacy of EV's content after cellular uptake and needs attention in EV-based DDSs.


Assuntos
Arginina , Peptídeos Penetradores de Células/farmacocinética , Vesículas Extracelulares/metabolismo , Veículos Farmacêuticos , Saporinas/farmacocinética , Animais , Células CHO , Sobrevivência Celular , Peptídeos Penetradores de Células/administração & dosagem , Peptídeos Penetradores de Células/química , Cricetulus , Liofilização , Humanos , Tamanho da Partícula , Pinocitose , Preservação Biológica/métodos , Saporinas/administração & dosagem , Tetraspanina 30/metabolismo
13.
Sci Rep ; 9(1): 16950, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740778

RESUMO

Human limbus-derived stromal/mesenchymal stem cells (hLMSC) can be one of the alternatives for the treatment of corneal scars. However, reliable methods of storing and transporting hLMSC remains a serious translational bottleneck. This study aimed to address these limitations by encapsulating hLMSC in alginate beads. Encapsulated hLMSC were kept in transit in a temperature-conditioned container at room temperature (RT) or stored at 4 °C for 3-5 days, which is the likely duration for transporting cells from bench-to-bedside. Non-encapsulated cells were used as controls. Post-storage, hLMSC were released from encapsulation, and viability-assessed cells were plated. After 48 and 96-hours in culture the survival, gene-expression and phenotypic characteristics of hLMSC were assessed. During transit, the container maintained an average temperature of 18.6 ± 1.8 °C, while the average ambient temperature was 31.4 ± 1.2 °C (p = 0.001). Encapsulated hLMSC under transit at RT were recovered with a higher viability (82.5 ± 0.9% and 76.9 ± 1.9%) after 3 (p = 0.0008) and 5-day storage (p = 0.0104) respectively as compared to 4 °C (65.2 ± 1.2% and 64.5 ± 0.8% respectively). Cells at RT also showed a trend towards greater survival-rates when cultured (74.3 ± 2.9% and 67.7 ± 9.8%) than cells stored at 4 °C (54.8 ± 9.04% and 52.4 ± 8.1%) after 3 and 5-days storage (p > 0.2). Non-encapsulated cells had negligible viability at RT and 4 °C. Encapsulated hLMSC (RT and 4 °C) maintained their characteristic phenotype (ABCG2, Pax6, CD90, p63-α, CD45, CD73, CD105, Vimentin and Collagen III). The findings of this study suggest that alginate encapsulation is an effective method of hLMSC preservation offering high cell viability over prolonged durations in transit at RT, therefore, potentially expanding the scope of cell-based therapy for corneal blindness.


Assuntos
Limbo da Córnea/citologia , Células-Tronco Mesenquimais , Preservação Biológica/métodos , Manejo de Espécimes/métodos , Alginatos , Sobrevivência Celular , Expressão Gênica , Marcadores Genéticos , Humanos , Índia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Preservação Biológica/instrumentação , Manejo de Espécimes/instrumentação , Temperatura
14.
PLoS One ; 14(9): e0221831, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31490969

RESUMO

The preservation of biological samples for an extended time period of days to weeks after initial collection is important for the identification, screening, and characterization of bacterial pathogens. Traditionally, preservation relies on cold-chain infrastructure; however, in many situations this is impractical or not possible. Thus, our goal was to develop alternative bacterial sample preservation and transport media that are effective without refrigeration or external instrumentation. The viability, nucleic acid stability, and protein stability of Bacillus anthracis Sterne 34F2, Francisella novicida U112, Staphylococcus aureus ATCC 43300, and Yersinia pestis KIM D27 (pgm-) was assessed for up to 28 days. Xanthan gum (XG) prepared in PBS with L-cysteine maintained more viable F. novicida U112 cells at elevated temperature (40°C) compared to commercial reagents and buffers. Viability was maintained for all four bacteria in XG with 0.9 mM L-cysteine across a temperature range of 22-40°C. Interestingly, increasing the concentration to 9 mM L-cysteine resulted in the rapid death of S. aureus. This could be advantageous when collecting samples in the built environment where there is the potential for Staphylococcus collection and stabilization rather than other organisms of interest. F. novicida and S. aureus DNA were stable for up to 45 days upon storage at 22°C or 40°C, and direct analysis by real-time qPCR, without DNA extraction, was possible in the XG formulations. XG was not compatible with proteomic analysis via LC-MS/MS due to the high amount of residual Xanthomonas campestris proteins present in XG. Our results demonstrate that polysaccharide-based formulations, specifically XG with L-cysteine, maintain bacterial viability and nucleic acid integrity for an array of both Gram-negative and Gram-positive bacteria across ambient and elevated temperatures.


Assuntos
Bactérias/efeitos dos fármacos , Polissacarídeos/farmacologia , Preservação Biológica/métodos , Bactérias/citologia , Bactérias/metabolismo , Cisteína/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Proteômica , Temperatura
15.
PLoS One ; 14(9): e0222006, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31490977

RESUMO

Dextranol, a reduced dextran, prevents damage to stored dry protein samples that unmodified dextran would otherwise cause. Desiccation protectants (xeroprotectants) like the polysaccharide dextran are critical for preserving dried protein samples by forming a rigid glass that protects entrapped protein molecules. Stably dried proteins are important for maintaining critical information in clinical samples like blood serum as well as maintaining activity of biologic drug compounds. However, we found that dextran reacts with both dried serum proteins and lyophilized purified proteins during storage, producing high-molecular weight Amadori-product conjugates. These conjugates appeared in a matter of days or weeks when stored at elevated temperatures (37° or 45°C), but also appeared on a timescale of months when stored at room temperature. We synthesized a less reactive dextranol by reducing dextran's anomeric carbon from an aldehyde to an alcohol. Serum samples dried in a dextranol-based matrix protected the serum proteins from forming high-molecular weight conjugates. The levels of four cancer-related serum biomarkers (prostate specific antigen, neuropilin-1, osteopontin, and matrix-metalloproteinase 7) decreased, as measured by immunoassay, when serum samples were stored for one to two weeks in dextran-based matrix. Switching to a dextranol-based xeroprotection matrix slightly reduced the damage to osteopontin and completely stopped any detectable damage during storage in the other three biomarkers when stored for a period of two weeks at 45°C. We also found that switching from dextran to dextranol in a lyophilization formulation eliminates this unwanted reaction, even at elevated temperatures. Dextranol offers a small and easy modification to dextran that significantly improves the molecule's function as a xeroprotectant by eliminating the potential for damaging protein-polysaccharide conjugation.


Assuntos
Dextranos/química , Dextranos/farmacologia , Preservação Biológica/métodos , Proteínas Sanguíneas/química , Dessecação , Composição de Medicamentos , Oxirredução , Estabilidade Proteica/efeitos dos fármacos , Temperatura
16.
Rev. argent. microbiol ; 51(3): 214-220, set. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1041827

RESUMO

Reference fungal cultures (RFCs) are essential for the internal quality control of laboratories. The production of these cultures requires standardized procedures (IRAM 14950:2016 and ISO 17034:2016 standards) carried out by a recognized and accredited laboratory. The aim of this work was to produce RFC in paper disks of autochthonous strains, characterized by two, homogeneous and stable reference methods traceable at species level. RFC were produced using 14 regional species (7 yeasts and 7 filamentous fungi) from the fungal culture collection (DMic). Paper disks were impregnated with a culture suspension, dried and packed. Homogeneity, viability, identity and purity were verified. Short-and long-term stability at different temperatures and storage times were studied. Characterization of each strain allowed to confirm its identity and to ensure its traceability at international level. Produced batches were homogeneous and stable at -20 ±5 °C for 30 months. This method of production was adequate to produce homogeneous and stable RFC with phenotypic and genotypic characteristics correctly defined and internationally traceable. Standardized procedures were developed for the production of certified RFC that could be transferred to other microorganisms. Providing RFC that represent regional strains allows laboratories to produce more reliable results with a favorable impact on medical diagnosis, the environment or the food industry.


Los cultivos microbianos de referencia (CR) son imprescindibles para el control de calidad interno de los laboratorios. Asegurar su producción requiere de procedimientos estandarizados (IRAM 14950:2016 e ISO 17034:2016) realizados en un laboratorio reconocido y acreditado. El objetivo de este estudio fue producir cultivos fúngicos de referencia en discos de papel, a partir de un panel de cultivos autóctonos caracterizados por dos métodos de referencia, trazables a nivel taxonómico de especie, homogéneos y estables. Se produjeron CR de 14 especies circulantes en Argentina (7 de levaduras y 7 de hongos miceliales), depositadas en la colección de hongos de interés médico (DMic). Los discos de papel fueron embebidos con una suspensión del cultivo por producir, secados y envasados. Se verificó la homogeneidad, viabilidad, identidad y pureza de cada lote. Se evaluó la estabilidad a corto y largo plazo a distintas temperaturas y tiempos de almacenamiento. La caracterización de cada CR nos permitió confirmar su identidad y asegurar su trazabilidad a nivel internacional. Los lotes producidos fueron homogéneos y estables durante 30 meses conservados a -20 ±5 °C. Este método resultó adecuado para producir CR homogéneos y estables, con características fenotípicas y genotípicas correctamente definidas y trazables a nivel internacional. Los procedimientos estandarizados desarrollados en este trabajo pueden ser transferidos para producir CR certificados de otros microorganismos. La provisión de CR que represente cepas regionales permite a los laboratorios producir resultados más confiables con un impacto favorable en el diagnóstico médico, los estudios ambientales y la industria alimenticia.


Assuntos
Bancos de Espécimes Biológicos , Fungos , Micologia/normas , Preservação Biológica/instrumentação , Preservação Biológica/métodos , Controle de Qualidade , Padrões de Referência , Leveduras , Meios de Cultura , Micologia/métodos
17.
Microb Biotechnol ; 12(5): 849-855, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31225698

RESUMO

The preservation of the viability of microorganisms in probiotic formulations is the most important parameter ensuring the adequate concentration of live microorganisms at the time of administration. The formulation and processing techniques used to produce these probiotic formulations can influence the preservation of the microbial viability. However, it is also required that the bacteria maintain their key probiotic capacities during processing, formulation and shelf life. In this study, we investigated the impact of spray-drying on different cell wall properties of the model probiotic strain Lactobacillus rhamnosus GG, including its adherence to intestinal epithelial cells. The dltD gene knock-out mutant, L. rhamnosus GG CMPG5540, displaying modified cell wall lipoteichoic acids, showed significantly increased colony-forming units after spray-drying and subsequent storage under standard conditions compared to wild-type L. rhamnosus GG. In contrast, disruption of the biosynthesis of exopolysaccharides or pili expression did not impact survival. However, spray-drying did significantly affect the adherence capacity of L. rhamnosus GG. Scanning electron microscopy confirmed that the pili, key surface factors for adherence to intestinal cells and mucus, were sheared off during the spray-drying process. These data thus highlight that both the functionality and viability of probiotics should be assessed during the spray-drying process and subsequent storage.


Assuntos
Desidratação , Dessecação/métodos , Lacticaseibacillus rhamnosus/fisiologia , Viabilidade Microbiana , Preservação Biológica/métodos , Aderência Bacteriana , Contagem de Colônia Microbiana , Células Epiteliais/microbiologia , Probióticos
19.
Mil Med ; 184(Suppl 1): 43-47, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30901456

RESUMO

OBJECTIVES: Today's surgical trainees have less exposure to open vascular and trauma procedures. Lightly embalmed cadavers may allow a reusable model that maximizes resources and allows for repeat surgical training over time. METHODS: This was a three-phased study that was conducted over several months. Segments of soft-embalmed cadaver vessels were harvested and perfused with tap water. To test durability, vessels were clamped, then an incision was made and repaired with 5-0 polypropylene. Tolerance to suturing and clamping was graded. In a second phase, both an arterial-synthetic graft and an arterial-venous anastomosis were performed and tested at 90 mmHg perfusion. In the final phase, lower extremity regional perfusion was performed and vascular control of a simulated injury was achieved. RESULTS: Seven arteries and six veins from four cadavers were explanted. All vessels accommodated suture repair over 6 weeks. There was minor leaking at all previous clamp sites. In the anastomotic phase, vessels tolerated grafting, clamping, and perfusion without tearing or leaking. Regional perfusion provided a life-like training scenario. CONCLUSIONS: Explanted vessels of soft-embalmed cadavers show adequate durability over time with realistic vascular surgery handling characteristics. This shows promise as initial proof of concept for a reusable perfused cadaver model. Further study with serial regional and whole-body perfusion is warranted.


Assuntos
Cadáver , Preservação Biológica/normas , Procedimentos Cirúrgicos Vasculares/educação , Humanos , Perfusão/métodos , Preservação Biológica/métodos , Estudo de Prova de Conceito
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