Simultaneous enumeration of yeast and bacterial cells in the context of industrial bioprocesses.

In scenarios where yeast and bacterial cells coexist, it is of interest to simultaneously quantify the concentrations of both cell types, since traditional methods used to determine these concentrations individually take more time and resources. Here, we compared different methods for quantifying the fuel ethanol Saccharomyces cerevisiae PE-2 yeast strain and cells from the probiotic Lactiplantibacillus plantarum strain in microbial suspensions. Individual suspensions were prepared, mixed in 1:1 or 100:1 yeast-to-bacteria ratios, covering the range typically encountered in sugarcane biorefineries, and analyzed using bright field microscopy, manual and automatic Spread-plate and Drop-plate counting, flow cytometry (at 1:1 and 100:1 ratios), and a Coulter Counter (at 1:1 and 100:1 ratios). We observed that for yeast cell counts in the mixture (1:1 and 100:1 ratios), flow cytometry, the Coulter Counter, and both Spread-plate options (manual and automatic CFU counting) yielded statistically similar results, while the Drop-plate and microscopy-based methods gave statistically different results. For bacterial cell quantification, the microscopy-based method, Drop-plate, and both Spread-plate plating options and flow cytometry (1:1 ratio) produced no significantly different results (p > .05). In contrast, the Coulter Counter (1:1 ratio) and flow cytometry (100:1 ratio) presented results statistically different (p < .05). Additionally, quantifying bacterial cells in a mixed suspension at a 100:1 ratio wasn't possible due to an overlap between yeast cell debris and bacterial cells. We conclude that each method has limitations, advantages, and disadvantages. ONE-SENTENCE SUMMARY: This study compares methods for simultaneously quantifying yeast and bacterial cells in a mixed sample, highlighting that in different cell proportions, some methods cannot quantify both cell types and present distinct advantages and limitations regarding time, cost, and precision.

Approach to classification of cavitary effusion and comparison between manual and automatic methods for total nucleated cell count

Background: Two classifications are used to categorize cavitary effusions using total nucleated cell count (TNCC): protein concentration and pathophysiology of its formation. The aims of the present study were to evaluate the correlation between the TNCC values of cavitary effusions obtained in the automatic and the manual method, and also evaluating the classification methodology.Materials, Methods & Results: Cavitary effusions were analyzed for physical, chemical and cytological aspects, as well as manual and automatic cell counts for the correlation between the traditional methods and those suggested by Stockham & Scott. Bland-Altman regression and Spearman correlation analysis were performed. Of the total, 44 were abdominal effusions (73.3%), 15 thoracic (25%) and 1 pericardial (1.7%). According to the traditional classification, most of the effusions were classified as modified transudates (40%) and according to the classification of Stockham and Scott, as transudates poor in protein (31.7%). The correlation between cell counting techniques between pure, modified and exudate transudates was 0.94, 0.97 and 0.94, respectively, indicating an excellent correlation between the parameters (P = 0.95%).Discussion: Considering the concentration of proteins and CCNT, the effusions classified as modified transudate were mainly caused by neoplastic processes (carcinomas/adenocarcinomas), since there are several mechanisms of their formation, such as large variation of protein concentration. According to the Stockham & Scott classification a unique classification is considered for exfoliative neoplastic effusions, the variation of the protein concentration of the effusion does not alter its classification. In neoplastic effusions, classified as exudates, lymphomas were the most prevalent, and hypercellularity (approximately 150,000 cells / μL) allowed this classification.[...]

Approach to classification of cavitary effusion and comparison between manual and automatic methods for total nucleated cell count

Background: Two classifications are used to categorize cavitary effusions using total nucleated cell count (TNCC): protein concentration and pathophysiology of its formation. The aims of the present study were to evaluate the correlation between the TNCC values of cavitary effusions obtained in the automatic and the manual method, and also evaluating the classification methodology.Materials, Methods & Results: Cavitary effusions were analyzed for physical, chemical and cytological aspects, as well as manual and automatic cell counts for the correlation between the traditional methods and those suggested by Stockham & Scott. Bland-Altman regression and Spearman correlation analysis were performed. Of the total, 44 were abdominal effusions (73.3%), 15 thoracic (25%) and 1 pericardial (1.7%). According to the traditional classification, most of the effusions were classified as modified transudates (40%) and according to the classification of Stockham and Scott, as transudates poor in protein (31.7%). The correlation between cell counting techniques between pure, modified and exudate transudates was 0.94, 0.97 and 0.94, respectively, indicating an excellent correlation between the parameters (P = 0.95%).Discussion: Considering the concentration of proteins and CCNT, the effusions classified as modified transudate were mainly caused by neoplastic processes (carcinomas/adenocarcinomas), since there are several mechanisms of their formation, such as large variation of protein concentration. According to the Stockham & Scott classification a unique classification is considered for exfoliative neoplastic effusions, the variation of the protein concentration of the effusion does not alter its classification. In neoplastic effusions, classified as exudates, lymphomas were the most prevalent, and hypercellularity (approximately 150,000 cells / μL) allowed this classification.[...](AU)

Cellular exudation induced by carrageenan in the peritoneal cavity of chicks / Exsudação celular induzida pela carragenina na cavidade peritoneal de pintos

The cellular response, induced by the carrageenan injection (4.5 ml; 0.2% w/v) in Ringer-Locke solution into the peritoneal cavity of chicks (three to six-week old Isa Brown males), was evaluated by total and differential inflammatory cell counting of exudates collected 0.5 to 4 hours after stimulus. An increased leucocyte exudation, with predominance of heterophils, wasobserved within 1 and 4 hours post-stimulus. Macrophages were the second predominant cell type, followed by lymphocytes, eosinophils and basophils, in decreasing order. Thrombocytes were not significant in the peritoneal inflammatory exudate. Results presented in this work indicate that the peritoneal cavity can be utilized as a good model for studying the acuteinflammatory response of chickens.

A resposta celular, induzida pela injeção de carragenina (4,5 ml de solução de Ringer-Locke a 0,2% w/v) na cavidade peritoneal de pintos (machos Isa Brown de três a seis semanas de idade), foi avaliada pela contagem total e diferencial das células inflamatórias de exsudatos colhidos de 0,5 a 4 horas pós-estímulo. Foi observado ao longo de 1 a 4 horas após a injúria um aumento da exsudação leucocitária, com predominância de heterófilos. Macrófagos foram o segundo tipo celular predominante, seguidos por linfócitos, eosinófilos e basófilos, em ordem decrescente. Trombócitos não foram observados em número significante no exsudato inflamatório. Os resultados apresentados neste trabalho indicam que a cavidade peritoneal pode ser usada como um bom modelo para o estudo da resposta inflamatória aguda em galinhas.