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1.
Glob Health Med ; 6(2): 93-100, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38690131

RESUMO

Seasonal influenza is an acute respiratory infection primarily caused by influenza A and B viruses, which circulate annually and cause substantial morbidity and mortality worldwide. Annual influenza vaccination is currently the most effective measure for preventing influenza and greatly reduces the risk of disease severity and the incidence of complications and death. Annual seasonal influenza vaccines are traditionally produced in Japan and many other countries using viruses propagated in embryonated chicken eggs. However, at present, the effectiveness of the seasonal influenza vaccines has some significant limitations, partly because of egg-adaptive mutations in the antigenic sites of the influenza virus haemagglutinin, which are caused by the continued evolution of seasonal influenza viruses. To overcome the limitations of egg-based influenza vaccine production, a mammalian cell culture-based influenza vaccine production system has been developed in Japan in the past decade as an alternative to the current production method. In this review, I have summarised the progress in the development of cell-based seasonal influenza vaccines and discussed the technological challenges encountered in the development of influenza vaccines.

2.
Polim Med ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38545926

RESUMO

BACKGROUND: There is a lack of studies evaluating the toxicity of nitric oxide (NO) precursors in chitosan/L-arginine hydrogels and their topical administration. However, clarifying the characteristics of these elements is essential for their possible use in non-surgical techniques of tooth movement acceleration. Such characteristics include interaction with different cell types, metabolism and drug safety. OBJECTIVES: This in vitro study aimed to assess the cytotoxicity of chitosan hydrogels on human HeLa cells using different concentrations of L-arginine. MATERIAL AND METHODS: The hydrogels were synthesized in a materials engineering laboratory, with a controlled environment, using 4 different L-arginine concentrations of 0%, 10%, 15%, and 20%. Once the hydrogels were prepared, their physical and chemical properties were characterized, and viability analysis was performed using 2 different methods, including a 48-h assay with Artemia salina nauplii and a 24-h cell culture with human HeLa cells followed by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation assay. Data analysis was performed using a Mann-Whitney U test to evaluate positive and negative controls in the cell culture, with a significance level of 0.01. A Wilcoxon paired test contrasted the 24-h compared to 48-h Artemia salina assays, with a Kruskal-Wallis and post hoc Dunn test used to compare groups using a significance level of 0.05. RESULTS: In the more viscous hydrogels, Artemia salina nauplii decreased drastically in 24 h, while the 15% and 20% hydrogels had no statistical differences from the negative control. The 10% and 20% hydrogels were statistically different from the negative control when comparing cell culture data. CONCLUSIONS: Our findings suggest that chitosan/L-arginine hydrogels could be used in humans without toxic effects. However, more trials and tests are needed to evaluate tooth movement rate during orthodontic treatment.

3.
Laryngoscope ; 134(6): 2748-2756, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38288866

RESUMO

OBJECTIVE: To establish and characterize a diverse library of head and neck squamous cell cancer (HNSCC) cultures using conditional reprogramming (CR). METHODS: Patients enrolled on an IRB-approved protocol to generate tumor cell cultures using CR methods. Tumor and blood samples were collected and clinical information was recorded. Successful CR cultures were validated against banked reference tumors with short tandem repeat genotyping. Cell morphology was archived with photodocumentation. Clinical and demographic factors were evaluated for associations with successful establishment of CR culture. Human papilloma virus (HPV) genotyping, clonogenic survival, MTT assays, spheroid growth, and whole exome sequencing were carried out in selected cultures. RESULTS: Forty four patients were enrolled, with 31 (70%) successful CR cultures, 32% derived from patients who identified as Black and 61% as Hispanic. All major head and neck disease sites were represented, including 15 (48%) oral cavity and 8 (26%) p16-positive oropharynx cancers. Hispanic ethnicity and first primary tumors (vs. second primary or recurrent tumors) were significantly associated with successful CR culture. HPV expression was conserved in CR cultures, including CR-024, which carried a novel HPV-69 serotype. CR cultures were used to test cisplatin responses using MTT assays. Previous work has also demonstrated these models can be used to assess response to radiation and can be engrafted in mouse models. Whole exome sequencing demonstrated that CR cultures preserved tumor mutation burden and driver mutations. CONCLUSION: CR culture is highly successful in propagating HNSCC cells. This study included a high proportion of patients from underrepresented minority groups. LEVEL OF EVIDENCE: Not Applicable Laryngoscope, 134:2748-2756, 2024.


Assuntos
Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Neoplasias de Cabeça e Pescoço/genética , Feminino , Masculino , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Pessoa de Meia-Idade , Células Tumorais Cultivadas , Idoso , Sequenciamento do Exoma , Reprogramação Celular/genética , Adulto , Técnicas de Reprogramação Celular
4.
BMC Res Notes ; 17(1): 40, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287416

RESUMO

OBJECTIVE: Proteus mirabilis is related to serious infections. The present study was designed to investigate the minimum inhibitory concentration (MIC) of silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnONPs) and cytotoxicity among P. mirabilis isolates recovered from clinical samples in Shiraz. RESULTS: A total of 100 P. mirabilis isolates were screened by biochemical tests and polymerase chain reaction (PCR). Also, 25 (25%) and 7 (7%) isolates were positive for extended-spectrum beta-lactamase (ESBLs) and carbapenemase, respectively. Synthesized nanoparticles were characterized by UV-vis spectrum, X-ray diffraction (XRD), and electron microscopy. The average size of AgNPs and ZnONPs in the present study is 48 and < 70 nm, respectively. The MIC and the MBC of the ZnONPs were in the range of 31.25 µg/ml and 62.5 µg/mL, respectively. Also, for AgNPs, the MIC and the MBC were in the range of 7.8 µg/mL and 15.6 µg/mL, respectively. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay in a primary culture of fibroblast L929 cells for this MIC indicated biocompatibility and low cytotoxicity of Ag NPs and for ZnONPs indicated significant cytotoxicity. Also, a MIC of AgNPs can be used as a therapeutic concentration without the effect of cytotoxicity in human cells.


Assuntos
Proteínas de Bactérias , Nanopartículas Metálicas , Óxido de Zinco , beta-Lactamases , Humanos , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Antibacterianos/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Proteus mirabilis , Nanopartículas Metálicas/química , Irã (Geográfico) , Testes de Sensibilidade Microbiana
5.
Acta Trop ; 250: 107092, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065375

RESUMO

Leishmaniases are zoonotic diseases caused by protozoa of the genus Leishmania. In Bolivia, leishmaniasis occurs mainly in the cutaneous form (CL) followed by the mucosal or mucocutaneous form (ML or MCL), grouped as tegumentary leishmaniosis (TL), while cases of visceral leishmaniasis (VL) are rare. The cases of TL are routinely diagnosed by parasitological methods: Direct Parasitological Exam (DPE) and axenic culture, the latter being performed only by specialized laboratories. The aim of the present study was to optimize the parasitological diagnosis of TL in Bolivia, using two sampling methods. Samples from 117 patients with suspected TL, obtained by aspiration (n = 121) and scraping (n = 121) of the edge of the lesion were tested by: direct parasitological exam, culture in TSTB medium, and miniculture and microculture in Schneider's medium. A positive laboratory result by any of the four techniques evaluated using either of the two sampling methods was considered the gold standard. Of the 117 suspected patients included, TL was confirmed in 96 (82 %), corresponding 79 of the confirmed cases (82.3 %) to CL and 16 (16.7 %) to ML. Parasitological techniques specificity was 100 % and their analytical sensitivity was greater with scraping samples in TSTB culture (98 %). Scraping samples in TSTB and miniculture correlated well with the reference (Cohen's kappa coefficient=0.88) and showed good reliability (Cronbach's alpha coefficient ≥0.91). Microculture provided positive results earlier than the other culture methods (mean day 4.5). By day 14, 98 % of positive cultures had been detected. Scraping sampling and miniculture were associated with higher culture contamination (6 % and 17 %, respectively). Bacterial contamination predominated, regardless of the sampling and culture method, while filamentous fungi and mixed contamination were more frequently observed in cultures from scraping samples. In conclusion: (i) scraping samples proved more suitable for the diagnosis of TL as they increased analytical sensitivity, are less traumatic for the patient and are safer for laboratory personnel than aspirates; (ii) culture, mainly in TSBT medium, should be used for the diagnosis of TL due to its high sensitivity (doubling the number of cases diagnosed by DPE) and its low cost compared to other culture media.


Assuntos
Leishmania , Leishmaniose Cutânea , Leishmaniose Visceral , Leishmaniose , Humanos , Bolívia , Reprodutibilidade dos Testes , Leishmaniose/diagnóstico , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/parasitologia , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/parasitologia
6.
Microbiol Spectr ; 12(1): e0341823, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38063356

RESUMO

IMPORTANCE: This study is important because it shows the potential epidemiological silence associated with the use of culture as the primary diagnostic method for the laboratory identification of human campylobacteriosis. Also, we show how polymerase chain reaction methods are associated with a systematic increase in the number of human campylobacteriosis episodes as reported by routine disease surveillance. These findings are operationally relevant and have public health implications because they tell how crucial it is to consider changes in diagnostic methods, e.g., in the epidemiological analysis of historical data and in the interpretation of future data in light of the past. We also believe that this study highlights how the synergy between microbiology and epidemiology is essential for disease surveillance.


Assuntos
Infecções por Campylobacter , Campylobacter , Gastroenterite , Humanos , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Estudos Retrospectivos , Campylobacter/genética , Dinamarca/epidemiologia , Reação em Cadeia da Polimerase
7.
Reprod Biomed Online ; 48(1): 103570, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37952277

RESUMO

The Association for the Study of Reproductive Biology (ASEBIR) Interest Group in Embryology (in Spanish 'Grupo de Interés de Embriología') reviewed key morphokinetic parameters to assess the contribution of time-lapse technology (TLT) to the ASEBIR grading system. Embryo grading based on morphological characteristics is the most widely used method in human assisted reproduction laboratories. The introduction and implementation of TLT has provided a large amount of information that can be used as a complementary tool for morphological embryo evaluation and selection. As part of IVF treatments, embryologists grade embryos to decide which embryos to transfer or freeze. At the present, the embryo grading system developed by ASEBIR does not consider dynamic events observed through TLT. Laboratories that are using TLT consider those parameters as complementary data for embryo selection. The aim of this review was to evaluate review time-specific morphological changes during embryo development that are not included in the ASEBIR scoring system, and to consider them as candidates to add to the scoring system.


Assuntos
Embrião de Mamíferos , Desenvolvimento Embrionário , Humanos , Imagem com Lapso de Tempo/métodos , Transferência Embrionária/métodos , Biologia , Técnicas de Cultura Embrionária , Implantação do Embrião , Fertilização in vitro/métodos , Blastocisto
8.
Acta cir. bras ; 39: e390524, 2024. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1533358

RESUMO

Purpose: We aimed to reveal the effects of rosmarinic acid (RA), which has come to the forefront with its antitumor and antioxidant properties in many studies recently in the ovarian adenocarcinoma cell line, on the epidermal growth factor receptor (EFGR) signaling pathway in the presence of doxorubicin (DOX). Methods: Ovarian adenocarcinoma cell line (OVCAR3) and human skin keratinocyte cell line human skin keratinocyte cell line (HaCaT) were used as control. (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was applied to determine the effect of RA and DOX on the proliferation of OVCAR3 and HaCaT cells. Bcl2 expression and epidermal growth factor receptor (EGFR) and western blot analysis were performed to determine the expression levels of the markers. Results: It was determined that RA (IC50 = 437.6 µM) and DOX (IC50 = 0.08 µM) have the ability to inhibit the proliferation of OVCAR3 cells and induce apoptosis in a 72-hour time and dose-dependent manner. Western blot showed that the expression level of Bcl-2 and EGFR in OVCAR3 cells was down-regulated by RA and DOX. Conclusions: Apoptosis in OVCAR3 cells can potentially be induced by RA via the EGFR pathway, and RA may be a potent agent for cancer therapy.


Assuntos
Neoplasias Ovarianas , Adenocarcinoma , Doxorrubicina/administração & dosagem , Receptores ErbB
9.
Journal of Clinical Hepatology ; (12): 246-251, 2024.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1007236

RESUMO

So far, there are still no specific treatment methods for severe hepatitis and liver failure, resulting in a mortality rate of over 70%, and they are the difficulties in the treatment of critical illness in China and globally. Liver transplantation is currently the most effective treatment method for end-stage liver disease, but only 1%‍ ‍—‍ ‍2% of patients can receive the opportunity for organ transplantation. The bioartificial liver support system utilizes external mechanical, physical, and biological devices to remove various harmful substances accumulated in the patient’s body, compensate for the metabolic functions of the liver, supplement necessary substances, improve internal environment, promote the recovery of liver function, help patients get through the critical period, and save time for liver transplantation, and therefore, it is considered one of the important methods for the treatment of end-stage liver disease. Since hepatocytes are the core element of bioartificial liver, this article summarizes the sources of liver seed cells, 3D culture methods, and corresponding bioreactor culture systems and hopes to gradually solve the core issue of large-scale in vitro preparation of hepatocytes to obtain hepatocytes with adequate quantity and quality, which urgently needs to be addressed in clinical application.

10.
J Clin Exp Hepatol ; 14(1): 101265, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38076367

RESUMO

Background and aims: Bacterial cholangitis is a common complication in patients with ischemic type biliary lesions and/or anastomotic strictures after liver transplantation (LTX). Patients frequently need antibiotics and endoscopic retrograde cholangiography (ERC) to improve the bile flow. Antibiotic treatment is based on findings in standard microbiological cultivation (SMC) of bile. However, the cultivation techniques are limited to a subset of bacteria easy-to-cultivate. Therefore, the aim of our study was to evaluate the value of next generation sequencing as an additional diagnostic tool to SMC in ischemic type biliary lesions and/or anastomotic strictures. Methods: We sequenced the V1-V2 region of the 16S rRNA gene in 242 stored bile samples in patients after LTX and compared the results with findings of SMC. SMC was performed in n = 135 (56%) fresh bile samples in addition to NGS. SMC was part of the clinical routine in these patients. Results: NGS detected bacterial genera in bile samples more often than SMC (P = 5.42 × 10-74). SMC showed insufficient discovery of bacterial genera compared to NGS with better performance in patients receiving antibiotics prior to ERC. SMC missed many bacterial genera detected by NGS. Conclusions: NGS was more sensitive in detecting bacteria in bile than SMC, no clinical parameters could be used to improve discovery rates in SMC and many genera were missed by SMC. Therefore, NGS should be used in a combined approach with SMC for improved diagnostics to achieve more specific and targeted antibiotic treatments.

11.
Int Endod J ; 57(1): 64-77, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37814380

RESUMO

AIM: To determine the cytotoxicity mechanism of 2.5% calcium hypochlorite [Ca(OCl)2 ] in L929 fibroblasts and the effect of this solution on human osteoblast-like cells (Saos-2) mineralization, compared to that of 2.5% sodium hypochlorite (NaOCl). METHODOLOGY: L929 fibroblasts were exposed to Ca(OCl)2 and NaOCl at different dilutions for 10 min. Cell metabolism was assessed by methyl-thiazole-tetrazolium (MTT); lysosome integrity, by neutral red (NR) assay; type of cell death, by flow cytometry (apoptosis/necrosis); cytoskeleton, by actin and α-tubulin fluorescence and cell ultrastructure, by transmission electron microscopy (TEM). The alkaline phosphatase (ALP) activity and mineralized nodule formation were determined in Saos-2 by thymolphthalein release and alizarin red staining (ARS), respectively. The data were analysed by two-way anova and Bonferroni's post-test (α = .05). RESULTS: Ca(OCl)2 promoted higher cell viability and a lower percentage of apoptosis and necrosis than NaOCl (p < .05). Ca(OCl)2 and NaOCl decreased cell metabolism and lysosome integrity, induced the breakdown of microtubules and actin filaments, promoted alterations of rough endoplasmic reticulum and disruption of mitochondrial cristae. Additionally, Ca(OCl)2 did not induce ALP activity and had no effect on mineralized nodules formation. CONCLUSIONS: Although Ca(OCl)2 and NaOCl promoted the same cytotoxicity mechanism, Ca(OCl)2 was less cytotoxic than NaOCl. As for ALP activity, no differences were observed between NaOCl and Ca(OCl)2 . The production of mineralized nodules induced by Ca(OCl)2 was lower than those induced by NaOCl, but was not different from those induced by the control group.


Assuntos
Fibroblastos , Hipoclorito de Sódio , Humanos , Hipoclorito de Sódio/toxicidade , Necrose , Osteoblastos , Irrigantes do Canal Radicular/farmacologia
12.
Front Neurosci ; 17: 1269664, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38144212

RESUMO

Alzheimer's disease (AD) is a devastating neurodegenerative condition with no effective treatments. Recent research highlights the role of NMDA receptors in AD development, as excessive activation of these receptors triggers excitotoxicity. Memantine, an NMDA receptor antagonist, shows promise in curbing excitotoxicity. What sets our study apart is our novel exploration of memantine's potential to protect hippocampal neurons from neurotoxicity induced by NMDA and amyloid ß1-42, a hallmark of AD. To achieve this, we conducted a series of experiments using rat hippocampal cell cultures. We employed Hoechst and propidium iodide double staining to assess neuronal viability. Analyzing the viability of neurons in normal conditions compared to their status after 24 h of exposure to the respective agents revealed compelling results. The incubation of hippocampal neurons with NMDA or amyloid ß1-42 led to a more than twofold increase in the number of apoptotic and necrotic neurons. However, when memantine was co-administered with NMDA or amyloid ß1-42, we witnessed a notable augmentation in the number of viable cells. This unique approach not only suggests that memantine may act as a neuroprotective agent but also emphasizes the relevance of hippocampal neuron cultures as valuable models for investigating excitotoxicity and potential AD treatments.

13.
J Pers Med ; 13(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38003933

RESUMO

Advances in the development of pharmacological treatment in oral cancer require tumor models capable of simulating the complex biology of the tumor microenvironment. The spread of three-dimensional models has changed the scenery of in vitro cell culture techniques, contributing to translational oncology. Still, the full extent of their application in preclinical drug trials is yet to be understood. Therefore, the present scoping review protocol was established to screen the literature on using three-dimensional cell culture models in drug-testing assays in the context of oral cancer. This scoping review will be conducted based on the guidelines established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Review guidelines (PRISMA-ScR). We will search the PubMed/Medline, Web of Science, Scopus, and Embase databases, as well as the gray literature, including peer-reviewed research articles involving 3D models applied to drug-assessment assays in oral cancer published from 1 March 2013 until 1 March 2023. Data will be charted, and findings will be described according to the predetermined questions of interest. We will present these findings in a narrative manner.

14.
Int J Stem Cells ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38030386

RESUMO

An enormous amount of current data has suggested involvement of endothelial progenitor cells (EPCs) in neovasculogenesis in both human and animal models. EPC level is an indicator of possible cardiovascular risk such as Alzheimer disease. EPC therapeutics requires its identification, isolation, differentiation and thus expansion. We approach here the peculiar techniques through current and previous reports available to find the most plausible and fast way of their expansion to be used in therapeutics. We discuss here the techniques for EPCs isolation from different resources like bone marrow and peripheral blood circulation. EPCs have been isolated by methods which used fibronectin plating and addition of various growth factors to culture media. Particularly, the investigations which tried to enhance EPC differentiation while inducing with growth factors and endothelial nitric oxide synthase are shared. We also include the cryopreservation and other storage methods of EPCs for a longer time. Sufficient amount of EPCs are required in transplantation and other therapeutics which signifies their in vitro expansion. We highlight the role of EPCs in transplantation which improved neurogenesis in animal models of ischemic stroke and human with acute cerebral infarct in the brain. Accumulatively, these data suggest the exhilarating route for enhancing EPC number to make their use in the clinic. Finally, we identify the expression of specific biomarkers in EPCs under the influence of growth factors. This review provides a brief overview of factors involved in EPC expansion and transplantation and raises interesting questions at every stage with constructive suggestions.

15.
Lasers Med Sci ; 38(1): 221, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749444

RESUMO

Photobiomodulation (PBM) has been proposed as a strategy to improve the regenerative capacity of human adipose-derived stem cells (hASCs). Yet, this effect has been proved in 2D culture conditions. To analyze the effect of different doses of laser irradiation (660 nm) with different levels of energy (1 J, 2 J and 6 J) on hASCs cultured at 2D and 3D conditions. We used gellan gum spongy-like hydrogels as a biomaterial to 3D culture hASCs. Different doses (1-7 daily irradiations) and energy levels (1-6 J) of PBM were applied, and the metabolic activity, viability, proliferation, and release of ROS and IL-8 was evaluated up to 7 days. In 3D, cell proliferation increased at high energy (6 J) and after a single dose of irradiation, while in 2D, metabolic activity and proliferation was enhanced only after 3 doses and independently of the energy. More than 1 dose was needed to promote ROS secretion both in 2D and 3D culture conditions. Interestingly, a decrease of IL-8 secretion was detected only in 3D after 3-7 daily irradiations. Overall, hASCs response to PBM was not only dependent on the energy level and the number of applied stimuli, but also on the in vitro culture conditions.


Assuntos
Interleucina-8 , Células-Tronco Mesenquimais , Humanos , Espécies Reativas de Oxigênio , Adipócitos , Bandagens
16.
Rev. peru. med. exp. salud publica ; 40(3): 297-306, jul. 2023. ilus, graf
Artigo em Espanhol | LILACS, INS-PERU | ID: biblio-1522787

RESUMO

Objetivo . Desarrollar y validar un método de suspensión celular utilizando células Vero 76 para el cultivo del virus Zika (ZIKV) basado en la infección de células recién sembradas no adheridas. Material y métodos . Se utilizaron tres multiplicidades de infección diferentes del ZIKV para desarrollar y comparar este novedoso método con el método estándar de monocapa de células confluentes. Además, validamos preliminarmente el método de suspensión utilizando muestras clínicas caracterizadas como positivas o negativas para el ZIKV. El método estándar de monocapa se utilizó como método de referencia, y el aislamiento viral se confirmó mediante un RT-PCR específico del ZIKV. Se estimó la sensibilidad e intervalos de confianza del 95% para el método de suspensión. Asimismo, se realizó una comparación técnica del método de suspensión contra el método de monocapa. Resultados . Nuestros hallazgos sugieren que tanto la carga viral como la replicación del ZIKV fueron comparables entre los métodos de infección en monocapa y en suspensión. Aunque ambos métodos fueron adecuados para cultivar y aislar el ZIKV, el método de suspensión se caracterizó por ser más fácil, barato y rápido, así como una técnica de aislamiento sensible. En comparación con el método de monocapa, el método de suspensión fue cuatro veces más sensible en la detección del ZIKV en casos inconclusos por RT-PCR. Conclusiones . El método de suspensión tiene el potencial de ser un método eficaz para cultivar y aislar el ZIKV y su uso es potencialmente útil tanto en la investigación como en entornos clínicos.


Objective. To develop and validate a cell suspension method using Vero 76 cells for culturing Zika virus (ZIKV) based on infection of detached freshly seeded cells. Material and methods. Three different multiplicities of infection of ZIKV were used to develop and compare this novel method to the standard confluent cell monolayer method. In addition, we preliminary validated the cell suspension method using well-characterized ZIKV positive and negative clinical samples. The standard confluent cell monolayer method was used as the reference method, and viral isolation was confirmed by a ZIKV-specific RT-PCR. The sensitivity and its 95% confidence intervals for the cell suspension method were estimated. Also, a technical comparison of the cell suspension method against the cell monolayer method was performed. Results. Our findings suggested that both the viral load and replication of ZIKV were comparable between both monolayer- and suspension-infection methods. Although both methods were suitable for culturing and isolating ZIKV, the cell suspension method was easier, cheaper, and quicker as well as a sensitive isolation technique. The cell suspension method was significantly more sensitive in detecting Zika in inconclusive cases by RT-PCR, with a fourfold increase compared to the confluent cell monolayer method. Conclusion. The cell suspension method has the potential to be an effective method for cultivating and isolating ZIKV and its application is potentially useful in both research and clinical settings.


Assuntos
Infecção por Zika virus , Técnicas de Cultura de Células , Vigilância em Saúde Pública
17.
Exp Dermatol ; 32(7): 1063-1071, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287089

RESUMO

A direct contact co-culture of skin explants to SZ95 sebocytes (3D-SeboSkin) has been shown to preserve the integrity of epidermal keratinocytes and dermis. In this study, the properties of epidermal melanocytes were evaluated in the same 3D SeboSkin ex vivo model. Skin explants (n = 6) were maintained in the 3D-SeboSkin model, in direct contact to fibroblasts and alone in serum-free medium (SFM). Histopathological, immunohistochemical, apoptosis and oil red staining evaluations were performed at Days 0 and 6 of incubation. Results revealed preservation and prominent proliferation of basal keratinocytes of the skin explants in addition to preservation of dermal collagen and vasculature at Day 6 in the 3D-SeboSkin culture model and to a lesser extent in co-culture with fibroblasts but not in SFM alone. Melan-A+/Ki67- epidermal melanocytes remained attached to the dermis even at sites of epidermal detachment in the three skin explant models tested. However, the number of epidermal melanocytes was significantly conserved in 3D-SeboSkin cultures in comparison with skin explants in SFM (p < 0.05), whereas no difference was found in comparison with the co-culture with fibroblasts. Few DAPI/TUNEL+ apoptotic melanocytes could mostly be observed in SFM-incubated skin explants. Furthermore, only SZ95 sebocytes in contact to skin explants in 3D-SeboSkin exhibited increased lipogenesis with accumulation of abundant lipid droplets. These results denote that the 3D-SeboSkin model yielded significant preservation of epidermal melanocytes and hence it is optimal for ex vivo studies of abnormalities of skin pigmentation, melanocyte neoplasms and effects of different hormones, cytokines, carcinogens and various therapeutics in a pattern that recapitulates the in vivo environment.


Assuntos
Epiderme , Pele , Técnicas de Cocultura , Melanócitos , Queratinócitos
18.
Front Med Technol ; 5: 1154653, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181099

RESUMO

Any Regenerative Medicine (RM) business requires reliably predictable cell and tissue products. Regulatory agencies expect control and documentation. However, laboratory tissue production is currently not predictable or well-controlled. Before conditions can be controlled to meet the needs of cells and tissues in culture for RM, we have to know what those needs are and be able to quantify them. Therefore, identification and measurement of critical cell quality attributes at a cellular or pericellular level is essential to generating reproducible cell and tissue products. Here, we identify some of the critical cell and process parameters for cell and tissue products as well as technologies available for sensing them. We also discuss available and needed technologies for monitoring both 2D and 3D cultures to manufacture reliable cell and tissue products for clinical and non-clinical use. As any industry matures, it improves and standardizes the quality of its products. Cytocentric measurement of cell and tissue quality attributes are needed for RM.

19.
Blood Res ; 58(S1): S46-S51, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37026380

RESUMO

Owing to donor-related issues, blood shortages and transfusion-related adverse reactions have become global issues of grave concern. In vitro manufactured red blood cells (RBCs) are promising substitutes for blood donation. In the United Kingdom, a clinical trial for allogeneic mini transfusion of cultured RBCs derived from primary hematopoietic stem cells has recently begun. However, current production quantities are limited and need improved before clinical use. New methods to enhance manufacturing efficiencies have been explored, including different cell sources, bioreactors, and 3-dimensional (3D) materials; however, further research is required. In this review, we discuss various cell sources for blood cell production, recent advances in bioreactor manufacturing processes, and the clinical applications of cultured blood.

20.
Antibiotics (Basel) ; 12(3)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36978356

RESUMO

The difficulty in recognizing early-onset neonatal sepsis (EONS) in a timely manner due to non-specific symptoms and the limitations of diagnostic tests, combined with the risk of serious consequences if EONS is not treated in a timely manner, has resulted in a low threshold for starting empirical antibiotic treatment. New guideline strategies, such as the neonatal sepsis calculator, have been proven to reduce the antibiotic burden related to EONS, but lack sensitivity for detecting EONS. In this review, the potential of novel, targeted preventive and diagnostic methods for EONS is discussed from three different perspectives: maternal, umbilical cord and newborn perspectives. Promising strategies from the maternal perspective include Group B Streptococcus (GBS) prevention, exploring the virulence factors of GBS, maternal immunization and antepartum biomarkers. The diagnostic methods obtained from the umbilical cord are preliminary but promising. Finally, promising fields from the newborn perspective include biomarkers, new microbiological techniques and clinical prediction and monitoring strategies. Consensus on the definition of EONS and the standardization of research on novel diagnostic biomarkers are crucial for future implementation and to reduce current antibiotic overexposure in newborns.

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