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1.
Microb Cell Fact ; 22(1): 99, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170263

RESUMO

BACKGROUND: In research and production, reproducibility is a key factor, to meet high quality and safety standards and maintain productivity. For microbial fermentations, complex substrates and media components are often used. The complex media components can vary in composition, depending on the lot and manufacturing process. These variations can have an immense impact on the results of biological cultivations. The aim of this work was to investigate and characterize the influence of the complex media component yeast extract on cultivations of Azotobacter vinelandii under microaerobic conditions. Under these conditions, the organism produces the biopolymer alginate. The focus of the investigation was on the respiration activity, cell growth and alginate production. RESULTS: Yeast extracts from 6 different manufacturers and 2 different lots from one manufacturer were evaluated. Significant differences on respiratory activity, growth and production were observed. Concentration variations of three different yeast extracts showed that the performance of poorly performing yeast extracts can be improved by simply increasing their concentration. On the other hand, the results with well-performing yeast extracts seem to reach a saturation, when their concentration is increased. Cultivations with poorly performing yeast extract were supplemented with grouped amino acids, single amino acids and micro elements. Beneficial results were obtained with the supplementation of copper sulphate, cysteine or a combination of both. Furthermore, a correlation between the accumulated oxygen transfer and the final viscosity (as a key performance indicator), was established. CONCLUSION: The choice of yeast extract is crucial for A. vinelandii cultivations, to maintain reproducibility and comparability between cultivations. The proper use of specific yeast extracts allows the cultivation results to be specifically optimised. In addition, supplements can be applied to modify and improve the properties of the alginate. The results only scratch the surface of the underlying mechanisms, as they are not providing explanations on a molecular level. However, the findings show the potential of optimising media containing yeast extract for alginate production with A. vinelandii, as well as the potential of targeted supplementation of the media.


Assuntos
Alginatos , Aminoácidos , Alginatos/química , Reprodutibilidade dos Testes , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo
2.
Microb Cell Fact ; 21(1): 145, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35843931

RESUMO

BACKGROUND: The fungal natural products illudin S and M have been investigated as precursors for the development of semisynthetic anticancer agents such as Irofulven (illudin S derivative) which is currently in phase II clinical trials. Recently, illudin M derivatives have shown improved in vitro selectivity towards cancer cells encouraging further investigation. This requires a stable supply of the precursor which is produced by Basidiomycota of the genus Omphalotus. We have recently reported a robust shake flask process for the production of gram quantities of illudin M from Omphalotus nidiformis aiming to transfer that process into stirred tank bioreactors, which can be used in a commercial production set-up. However, process transfer across different systems is not straightforward and particularly challenging when the producer is morphologically complex. There are only a few reports that address the development of bioprocesses for the production of compounds from Basidiomycota as these organisms have not been extensively studied because of their complex life cycles and often are difficult to cultivate under laboratory conditions. RESULTS: The recently developed shake flask process delivering stable titers of ~ 940 mg L-1 of illudin M was investigated using off-gas analysis to identify critical parameters which facilitated the transfer from shaken into stirred tank bioreactors. Comparable titers to the shake flask process were achieved in 2 L stirred tank bioreactors (1.5 L working volume) by controlling growth of biomass with a carefully timed pH-shift combined with an improved precursor-feeding strategy. A scale-up experiment in a 15 L bioreactor (10 L working volume), resembling the process at 1.5 L resulted in 523 mg L-1 and is the starting point for optimization of the identified parameters at that scale. CONCLUSION: By identifying and controlling key process parameters, the production process for illudin M was transferred from shake flasks into 2 L stirred tank bioreactors reaching a comparable titer (> 900 mg L-1), which is significantly higher than any previously reported. The insights obtained from 10 L scale pave the way towards further scale-up studies that will enable a sustainable supply of illudin M to support preclinical and clinical development programs.


Assuntos
Reatores Biológicos , Sesquiterpenos Policíclicos , Biomassa , Reatores Biológicos/microbiologia , Sesquiterpenos Policíclicos/metabolismo
3.
Eur J Immunol ; 50(3): 380-395, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31821534

RESUMO

Secondary diversification of the Ig repertoire occurs through somatic hypermutation (SHM), gene conversion (GCV), and class switch recombination (CSR)-three processes that are initiated by activation-induced cytidine deaminase (AID). AID targets Ig genes at orders of magnitude higher than the rest of the genome, but the basis for this specificity is poorly understood. We have previously demonstrated that enhancers and enhancer-like sequences from Ig genes are capable of stimulating SHM of neighboring genes in a capacity distinct from their roles in increasing transcription. Here, we use an in vitro proteomics approach to identify E-box, MEF2, Ets, and Ikaros transcription factor family members as potential binders of these enhancers. ChIP assays in the hypermutating Ramos B cell line confirmed that many of these factors bound the endogenous Igλ enhancer and/or the IgH intronic enhancer (Eµ) in vivo. Further investigation using SHM reporter assays identified binding sites for E2A and MEF2B in Eµ and demonstrated an association between loss of factor binding and decreases in the SHM stimulating activity of Eµ mutants. Our results provide novel insights into trans-acting factors that dictate SHM targeting and link their activity to specific DNA binding sites within Ig enhancers.


Assuntos
Hipermutação Somática de Imunoglobulina/fisiologia , Animais , Galinhas , Genes de Imunoglobulinas , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Trop Anim Health Prod ; 53(6): 524, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34705124

RESUMO

Whole genome sequencing of bovine breeds has allowed identification of genetic variants in milk protein genes. However, functional repercussion of such variants at a molecular level has seldom been investigated. Here, the results of a multistep Bioinformatic analysis for functional characterization of recently identified genetic variants in Brazilian Gyr and Guzerat breeds is described, including predicted effects on the following: (i) evolutionary conserved nucleotide positions/regions; (ii) protein function, stability, and interactions; (iii) splicing, branching, and miRNA binding sites; (iv) promoters and transcription factor binding sites; and (v) collocation with QTL. Seventy-one genetic variants were identified in the caseins (CSN1S1, CSN2, CSN1S2, and CSN3), LALBA, LGB, and LTF genes. Eleven potentially regulatory variants and two missense mutations were identified. LALBA Ile60Val was predicted to affect protein stability and flexibility, by reducing the number the disulfide bonds established. LTF Thr546Asn is predicted to generate steric clashes, which could mildly affect iron coordination. In addition, LALBA Ile60Val and LTF Thr546Asn affect exonic splicing enhancers and silencers. Consequently, both mutations have the potential of affecting immune response at individual level, not only in the mammary gland. Although laborious, this multistep procedure for classifying variants allowed the identification of potentially functional variants for milk protein genes.


Assuntos
Caseínas , Proteínas do Leite , Animais , Bovinos/genética , Simulação por Computador , Mutação , Regiões Promotoras Genéticas
5.
Biotechnol Bioeng ; 116(12): 3215-3227, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31429921

RESUMO

Oxygen supply is one of the most critical process parameters in aerobic cultivations. To assure sufficient oxygen supply, shake flasks are usually used in combination with orbital shaking machines. In this study, a measurement technique for the dissolved oxygen tension (DOT) in shake flask cultures with viscosity changes is presented. The movement of the shaker table is monitored by means of a Hall effect sensor. For DOT measurements, infrared fluorescent oxygen-sensitive nanoparticles are added to the culture broth. The position of the rotating bulk liquid needs to be determined to assure measurements inside the liquid. The leading edge of the bulk liquid is detected based on the fluorescence signal intensity of the oxygen-sensitive nanoparticles. Furthermore, online information about the viscosity of the culture broth is acquired due to the detection of the position of the leading edge of the bulk liquid relative to the direction of the centrifugal force, as described by Sieben et al. (2019. Sci. Rep., 9, 8335). The DOT measurement is combined with a respiration activity monitoring system which allows for the determination of the oxygen transfer rate (OTR) in eight parallel shake flasks. Based on DOT and OTR, the volumetric oxygen transfer coefficient (kL a) is calculated during cultivation. The new system was successfully applied in cultivations of Escherichia coli, Bacillus licheniformis, and Xanthomonas campestris.


Assuntos
Bacillus licheniformis/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Corantes Fluorescentes/química , Raios Infravermelhos , Nanopartículas/química , Oxigênio/análise , Xanthomonas campestris/crescimento & desenvolvimento , Fluorescência , Oxigênio/metabolismo
6.
Microb Cell Fact ; 17(1): 106, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-29986716

RESUMO

BACKGROUND: Culture media containing complex compounds like yeast extract or peptone show numerous disadvantages. The chemical composition of the complex compounds is prone to significant variations from batch to batch and quality control is difficult. Therefore, the use of chemically defined media receives more and more attention in commercial fermentations. This concept results in better reproducibility, it simplifies downstream processing of secreted products and enable rapid scale-up. Culturing bacteria with unknown auxotrophies in chemically defined media is challenging and often not possible without an extensive trial-and-error approach. In this study, a respiration activity monitoring system for shake flasks and its recent version for microtiter plates were used to clarify unknown auxotrophic deficiencies in the model organism Bacillus pumilus DSM 18097. RESULTS: Bacillus pumilus DSM 18097 was unable to grow in a mineral medium without the addition of complex compounds. Therefore, a rich chemically defined minimal medium was tested containing basically all vitamins, amino acids and nucleobases, which are essential ingredients of complex components. The strain was successfully cultivated in this medium. By monitoring of the respiration activity, nutrients were supplemented to and omitted from the rich chemically defined medium in a rational way, thus enabling a systematic and fast determination of the auxotrophic deficiencies. Experiments have shown that the investigated strain requires amino acids, especially cysteine or histidine and the vitamin biotin for growth. CONCLUSIONS: The introduced method allows an efficient and rapid identification of unknown auxotrophic deficiencies and can be used to develop a simple chemically defined tailor-made medium. B. pumilus DSM 18097 was chosen as a model organism to demonstrate the method. However, the method is generally suitable for a wide range of microorganisms. By combining a systematic combinatorial approach based on monitoring the respiration activity with cultivation in microtiter plates, high throughput experiments with high information content can be conducted. This approach facilitates media development, strain characterization and cultivation of fastidious microorganisms in chemically defined minimal media while simultaneously reducing the experimental effort.


Assuntos
Aminoácidos/química , Bacillus pumilus/metabolismo , Meios de Cultura/química , Bacillus pumilus/crescimento & desenvolvimento , Técnicas Bacteriológicas , Técnicas de Cultura Celular por Lotes , Fermentação , Reprodutibilidade dos Testes
7.
Microb Cell Fact ; 17(1): 69, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743073

RESUMO

BACKGROUND: Screening in the fed-batch operation mode is essential for biological cultivations facing challenges as oxygen limitation, osmotic inhibition, catabolite repression, substrate inhibition or overflow metabolism. As a screening tool on shake flask level, the membrane-based fed-batch shake flask was developed. While a controlled supply of a substrate was realized with the in-built membrane tip, the possibilities for replenishing nutrients and stabilizing pH values was not yet exploited. High buffer concentrations were initially used, shifting the medium osmolality out of the biological optimum. As the growth rate is predefined by the glucose release kinetics from the reservoir, the resulting medium acidification can be compensated with a controlled continuous supply of an alkaline compound. The focus of this research is to establish a simultaneous multi-component release of glucose and an alkaline compound from the reservoir to enable cultivations within the optimal physiological range of Escherichia coli. RESULTS: In combination with the Respiratory Activity MOnitoring System, the membrane-based fed-batch shake flask enabled the detection of an ammonium limitation. The multi-component release of ammonium carbonate along with glucose from the reservoir resulted not only in the replenishment of the nitrogen source but also in the stabilization of the pH value in the culture medium. A biomass concentration up to 25 g/L was achieved, which is one of the highest values obtained so far to the best of the author's knowledge with the utilization of a shake flask and a defined synthetic medium. Going a step further, the pH stabilization allowed the decrease of the required buffer amount to one-fourth establishing an optimal osmolality range for cultivation. As optimal physiological conditions were implemented with the multi-component release fed-batch cultivation, the supply of 0.2 g glucose in a 10 mL initial culture medium volume with 50 mM MOPS buffer resulted in a twofold higher biomass concentration than in a comparable batch cultivation. CONCLUSIONS: The newly introduced multi-component release with the membrane-based fed-batch shake flask serves a threefold purpose of replenishing depleted substrates in the culture medium, stabilizing the pH throughout the entire cultivation time and minimizing the necessary amount of buffer to maintain an optimal osmolality range. In comparison to a batch cultivation, these settings enable to achieve higher biomass and product concentrations.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Meios de Cultura/química , Escherichia coli/química
8.
Br Med Bull ; 121(1): 121-134, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28104630

RESUMO

Background: The new global target for maternal mortality ratio (MMR) is a ratio below 70 maternal deaths per 100 000 live births by 2030. We undertook a systematic review of methods used to measure MMR in low- and middle-income countries. Sources of data: Systematic review of the literature; 59 studies included. Areas of agreement: Civil registration (5 studies), census (5) and surveys (16), Reproductive Age Mortality Studies (RAMOS) (4) and the sisterhood methods (11) have been used to measure MMR in a variety of settings. Areas of controversy: Middle-income countries have used civil registration data for estimating MMR but it has been a challenge to obtain reliable data from low-income countries with many only using health facility data (18 studies). Growing points and areas for further research: Based on the strengths and feasibility of application, RAMOS may provide reliable and contemporaneous estimates of MMR while civil registration systems are being introduced. It will be important to build capacity for this and ensure implementation research to understand what works where and how.


Assuntos
Saúde Global , Renda/estatística & dados numéricos , Mortalidade Materna/tendências , Países em Desenvolvimento , Feminino , Saúde Global/estatística & dados numéricos , Inquéritos Epidemiológicos , Humanos , Vigilância da População , Gravidez , Fatores de Risco
9.
Microb Cell Fact ; 16(1): 122, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28716035

RESUMO

BACKGROUND: The initial part of process development involves extensive screening programs to identify optimal biological systems and cultivation conditions. For a successful scale-up, the operation mode on screening and production scale must be as close as possible. To enable screening under fed-batch conditions, the membrane-based fed-batch shake flask was developed. It is a shake flask mounted with a central feed reservoir with an integrated rotating membrane tip for a controlled substrate release. Building on the previously provided proof of principle for this tool, this work extends its application by constructive modifications and improved methodology to ensure reproducible performance. RESULTS: The previously limited operation window was expanded by a systematic analysis of reservoir set-up variations for cultivations with the fast-growing organism Escherichia coli. Modifying the initial glucose concentration in the reservoir as well as interchanging the built-in membrane, resulted in glucose release rates and oxygen transfer rate levels during the fed-batch phase varying up to a factor of five. The range of utilizable membranes was extended from dialysis membranes to porous microfiltration membranes with the design of an appropriate membrane tip. The alteration of the membrane area, molecular weight cut-off and liquid volume in the reservoir offered additional parameters to fine-tune the duration of the initial batch phase, the oxygen transfer rate level of the fed-batch phase and the duration of feeding. It was shown that a homogeneous composition of the reservoir without a concentration gradient is ensured up to an initial glucose concentration of 750 g/L. Finally, the experimental validity of fed-batch shake flask cultivations was verified with comparable results obtained in a parallel fed-batch cultivation in a laboratory-scale stirred tank reactor. CONCLUSIONS: The membrane-based fed-batch shake flask is a reliable tool for small-scale screening under fed-batch conditions filling the gap between microtiter plates and scaled-down stirred tank reactors. The implemented reservoir system offers various set-up possibilities, which provide a wide range of process settings for diverse biological systems. As a screening tool, it accurately reflects the cultivation conditions in a fed-batch stirred tank reactor and enables a more efficient bioprocess development.


Assuntos
Técnicas de Cultura Celular por Lotes/instrumentação , Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos , Diálise , Escherichia coli/crescimento & desenvolvimento , Filtração , Glucose/metabolismo , Microbiologia Industrial/métodos , Membranas Artificiais
10.
Anal Bioanal Chem ; 409(15): 3789-3797, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28374130

RESUMO

In the present work, DNA nanopore was composed of a bundle of six DNA duplexes folded from six DNA strands and functionalized with Ramos cell aptamer and cell-penetrating peptide (CPP). Herein, we present a unique dually conjugated molecule with an aptamer and cell-penetrating peptide for targeting and recognition of Ramos cells. The aptamer sequence was specific bound to Ramos cell, at the meanwhile the nanopore assembly was taken onto the surface of cell membrane and then got into the cells with the help of CPP. Specific targeting and increased intracellular uptake of nanostructures by Ramos cells were aimed. The intracellular uptake of the structure was determined using confocal microscopy. This study is the first to describe the recognition of tumor cells with functional DNA nanopores, establishing the foundation for the tumor cell detection with low cytotoxic agents. Graphical abstract DNA nanopore was composed of a bundle of six DNA duplexes folded from six DNA strands and functionalized with Ramos cell aptamer and cell-penetrating peptide. The dually conjugated molecule was found to show both improved cellular uptake and effective Ramos cell targeting.


Assuntos
Aptâmeros de Nucleotídeos/química , Peptídeos Penetradores de Células/química , DNA/química , Nanoporos , Neoplasias/diagnóstico por imagem , Linhagem Celular Tumoral , Células HeLa , Humanos , Microscopia Confocal/métodos , Nanoporos/ultraestrutura , Imagem Óptica/métodos
11.
BMC Pregnancy Childbirth ; 17(1): 275, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851302

RESUMO

BACKGROUND: The fifth Millennium Development Goal (MDG-5) aimed to improve maternal health, targeting a maternal mortality ratio (MMR) reduction of 75% between 1990 and 2015. The objective of this study was to identify all maternal deaths in Suriname, determine the extent of underreporting, estimate the reduction, audit the maternal deaths and assess underlying causes and substandard care factors. METHODS: A reproductive age mortality survey was conducted in Suriname (South-American upper-middle income country) between 2010 and 2014 to identify all maternal deaths in the country. MMR was compared to vital statistics and a previous confidential enquiry from 1991 to 1993 with a MMR 226. A maternal mortality committee audited the maternal deaths and identified underlying causes and substandard care factors. RESULTS: In the study period 65 maternal deaths were identified in 50,051 live births, indicating a MMR of 130 per 100.000 live births and implicating a 42% reduction of maternal deaths in the past 25 years. Vital registration indicated a MMR of 96, which marks underreporting of 26%. Maternal deaths mostly occurred in the urban hospitals (84%) and the causes were classified as direct (63%), indirect (32%) or unspecified (5%). Major underlying causes were obstetric and non-obstetric sepsis (27%) and haemorrhage (20%). Substandard care factors (95%) were mostly health professional related (80%) due to delay in diagnosis (59%), delay or wrong treatment (78%) or inadequate monitoring (59%). Substandard care factors most likely led to death in 47% of the cases. CONCLUSION: Despite the reduction in maternal mortality, Suriname did not reach MDG-5 in 2015. Steps to reach the Sustainable Development Goal in 2030 (MMR ≤ 70 per 100.000 live births) and eliminate preventable deaths include improving data surveillance, installing a maternal death review committee, and implementing national guidelines for prevention and management of major complications of pregnancy, childbirth and puerperium.


Assuntos
Serviços de Saúde Materna/estatística & dados numéricos , Mortalidade Materna , Complicações na Gravidez/mortalidade , Causas de Morte , Feminino , Humanos , Nascido Vivo/epidemiologia , Auditoria Médica , Erros Médicos/mortalidade , Gravidez , Suriname/epidemiologia
12.
Molecules ; 23(1)2017 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-29267250

RESUMO

Resveratrol is a polyphenolic natural compound produced by a variety of crops. Currently, resveratrol is considered a multi-target anti-cancer agent with pleiotropic activity, including the ability to prevent the proliferation of malignant cells by inhibiting angiogenesis and curtailing invasive and metastatic factors in many cancer models. However, the molecular mechanisms mediating resveratrol-specific effects on lymphoma cells remain unknown. To begin tackling this question, we treated the Burkitt's lymphoma cell line Ramos with resveratrol and assessed cell survival and gene expression. Our results suggest that resveratrol shows a significant anti-proliferative and pro-apoptotic activity on Ramos cells, inducing the DNA damage response, DNA repairing, and modulating the expression of several genes that regulate the apoptotic process and their proliferative activity.


Assuntos
Antineoplásicos/química , Resveratrol/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linfoma de Burkitt , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Resveratrol/farmacologia
13.
BMC Pregnancy Childbirth ; 16(1): 291, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27687243

RESUMO

BACKGROUND: Assessing the feasibility of conducting a prospective Reproductive Age Mortality Survey (RAMOS) study in the low-income setting of Mangochi District, Malawi to obtain cotemporaneous estimates of the number, cause of and conditions associated with maternal deaths (MD) in all women of reproductive age (WRA) (n = 207 688). METHODS: MD among all deaths of WRA were identified using the ICD-10 definition. Cause of death and contributing conditions identified by a panel of experts using the classification system for deaths during pregnancy, childbirth and puerperium (ICD-MM). RESULTS: Out of 424 deaths of WRA, 151 were MD giving a Maternal Mortality Ratio (MMR) of 363 per 100,000 live births (95 % CI: 307-425). Only 86 MD had been reported via existing reporting mechanisms representing an underreporting of 43 %. The majority of MD (62.3 %) occurred in a health facility and were the result of direct obstetric causes (74.8 %) with obstetric haemorrhage as the leading cause (35.8 %), followed by pregnancy-related infections (19.4 %), hypertensive disorders (16.8 %) and pregnancy with abortive outcome (13.2 %). Malaria was the most frequently identified indirect cause (9.9 %). Contributing conditions were more frequently identified when both verbal autopsy and facility-based death review had taken place and included obstructed labour (28.5 %), anaemia (12.6 %) and positive HIV status (4.0 %). CONCLUSION: The high number of MD that occur at health facility level, cause of death and contributing conditions reflect deficiencies in the quality of care at health facility level. A RAMOS is feasible in low- and middle-income settings and provides contemporaneous estimates of MMR.

14.
Stud Mycol ; 81: 85-147, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26955199

RESUMO

Families and genera assigned to Tremellomycetes have been mainly circumscribed by morphology and for the yeasts also by biochemical and physiological characteristics. This phenotype-based classification is largely in conflict with molecular phylogenetic analyses. Here a phylogenetic classification framework for the Tremellomycetes is proposed based on the results of phylogenetic analyses from a seven-genes dataset covering the majority of tremellomycetous yeasts and closely related filamentous taxa. Circumscriptions of the taxonomic units at the order, family and genus levels recognised were quantitatively assessed using the phylogenetic rank boundary optimisation (PRBO) and modified general mixed Yule coalescent (GMYC) tests. In addition, a comprehensive phylogenetic analysis on an expanded LSU rRNA (D1/D2 domains) gene sequence dataset covering as many as available teleomorphic and filamentous taxa within Tremellomycetes was performed to investigate the relationships between yeasts and filamentous taxa and to examine the stability of undersampled clades. Based on the results inferred from molecular data and morphological and physiochemical features, we propose an updated classification for the Tremellomycetes. We accept five orders, 17 families and 54 genera, including seven new families and 18 new genera. In addition, seven families and 17 genera are emended and one new species name and 185 new combinations are proposed. We propose to use the term pro tempore or pro tem. in abbreviation to indicate the species names that are temporarily maintained.

15.
Heliyon ; 10(10): e30690, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38770331

RESUMO

Probability distributions offer the best description of survival data and as a result, various lifetime models have been proposed. However, some of these survival datasets are not followed or sufficiently fitted by the existing proposed probability distributions. This paper presents a novel Kumaraswamy Odd Ramos-Louzada-G (KumORL-G) family of distributions together with its statistical features, including the quantile function, moments, probability-weighted moments, order statistics, and entropy measures. Some relevant characterizations were obtained using the hazard rate function and the ratio of two truncated moments. In light of the proposed KumORL-G family, a five-parameter sub-model, the Kumaraswamy Odd Ramos-Louzada Burr XII (KumORLBXII) distribution was introduced and its parameters were determined with the maximum likelihood estimation (MLE) technique. Monte Carlo simulation was performed and the numerical results were used to evaluate the MLE technique. The proposed probability distribution's significance and applicability were empirically demonstrated using various complete and censored datasets on the survival times of cancer and diabetes patients. The analytical results showed that the KumORLBXII distribution performed well in practice in comparison to its sub-models and several other competing distributions. The new KumORL-G for diabetes and cancer survival data is found extremely efficient and offers an enhanced and novel technique for modeling survival datasets.

16.
Drug Des Devel Ther ; 18: 1247-1262, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645988

RESUMO

Purpose: Sinomenine hydrochloride (SH) is used to treat chronic inflammatory diseases such as rheumatoid arthritis and may also be efficacious against Immunoglobulin A nephropathy (IgAN). However, no trial has investigated the molecular mechanism of SH on IgAN. Therefore, this study aims to investigate the effect and mechanism of SH on IgAN. Methods: The pathological changes and IgA and C3 depositions in the kidney of an IgAN rat model were detected by periodic acid-Schiff (PAS) and direct immunofluorescence staining. After extracting T and B cells using immunomagnetic beads, we assessed their purity, cell cycle phase, and apoptosis stage through flow cytometry. Furthermore, we quantified cell cycle-related and apoptosis-associated proteins by Western blotting. Results: SH reduced IgA and C3 depositions in stage 4 IgAN, thereby decreasing inflammatory cellular infiltration and mesangial injury in an IgAN model induced using heteroproteins. Furthermore, SH arrested the cell cycle of lymphocytes T and B from the spleen of IgAN rats. Regarding the mechanism, our results demonstrated that SH regulated the Cyclin D1 and Cyclin E1 protein levels for arresting the cell cycle and it also regulated Bax and Bcl-2 protein levels, thus increasing Cleaved caspase-3 protein levels in Jurkat T and Ramos B cells. Conclusion: SH exerts a dual regulation on the cell cycle and apoptosis of T and B cells by controlling cell cycle-related and apoptosis-associated proteins; it also reduces inflammatory cellular infiltration and mesangial proliferation. These are the major mechanisms of SH in IgAN.


Assuntos
Apoptose , Linfócitos B , Proliferação de Células , Glomerulonefrite por IGA , Morfinanos , Linfócitos T , Morfinanos/farmacologia , Morfinanos/química , Glomerulonefrite por IGA/tratamento farmacológico , Glomerulonefrite por IGA/patologia , Animais , Apoptose/efeitos dos fármacos , Ratos , Proliferação de Células/efeitos dos fármacos , Linfócitos B/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Masculino , Relação Dose-Resposta a Droga , Modelos Animais de Doenças , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Substâncias Protetoras/farmacologia , Substâncias Protetoras/química , Humanos , Células Cultivadas
17.
Biotechnol Prog ; : e3468, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602130

RESUMO

Cell line generation of mammalian cells is a time-consuming and labor-intensive process, especially because of challenges in clone selection after transfection. Antibiotics are common selection agents for mammalian cells due to their simplicity of use. However, the optimal antibiotic concentration must be determined with a kill curve experiment before clone selection starts. The traditional kill curve experiments are resource-intensive and time-consuming due to necessary sampling and offline analysis effort. This study, thus, explores the potential of online monitoring the oxygen transfer rate (OTR), as a non-invasive and efficient alternative for kill curve experiments. The OTR is monitored using the Transfer-rate Online Measurement (TOM) system and the micro(µ)-scale Transfer-rate Online Measurement (µTOM) device, which was used for mammalian cells first. It could be shown that the OTR curves for both devices align perfectly, affirming consistent cultivation conditions. The µTOM device proves effective in performing kill curve experiments in 96-deep-well plates without the need for sampling and offline analysis. The streamlined approach reduces medium consumption by 95%, offering a cost-effective and time-efficient solution for kill curve experiments. The study validates the generalizability of the method by applying it to two different CHO cell lines (CHO-K1 and sciCHO) with two antibiotics (puromycin and hygromycin B) each. In conclusion, the broad application of OTR online monitoring for CHO cell cultures in 96-deep-well plates is highlighted. The µTOM device proves as a valuable tool for high-throughput experiments, paving the way for diverse applications, such as media and clone screening, cytotoxicity tests, and scale-up experiments.

19.
Biotechnol Biofuels Bioprod ; 16(1): 49, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934285

RESUMO

BACKGROUND: The efficiency of downstream processes plays a crucial role in the transition from conventional petrochemical processes to sustainable biotechnological production routes. One promising candidate for product separation from fermentations with low energy demand and high selectivity is the adsorption of the target product on hydrophobic adsorbents. However, only limited knowledge exists about the interaction of these adsorbents and the bioprocess. The bioprocess could possibly be harmed by the release of inhibitory components from the adsorbent surface. Another possibility is co-adsorption of essential nutrients, especially in an in situ application, making these nutrients unavailable to the applied microorganism. RESULTS: A test protocol investigating adsorbent-bioprocess compatibility was designed and applied on a variety of adsorbents. Inhibitor release and nutrient adsorption was studied in an isolated manner. Respiratory data recorded by a RAMOS device was used to assess the influence of the adsorbents on the cultivation in three different microbial systems for up to six different adsorbents per system. While no inhibitor release was detected in our investigations, adsorption of different essential nutrients was observed. CONCLUSION: The application of adsorption for product recovery from the bioprocess was proven to be generally possible, but nutrient adsorption has to be assessed for each application individually. To account for nutrient adsorption, adsorptive product separation should only be applied after sufficient microbial growth. Moreover, concentrations of co-adsorbed nutrients need to be increased to compensate nutrient loss. The presented protocol enables an investigation of adsorbent-bioprocess compatibility with high-throughput and limited effort.

20.
Int J Data Sci Anal ; : 1-11, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36779042

RESUMO

Count data modeling's significance and its applicability to real-world occurrences have been emphasized in a number of research studies. The purpose of this work is to introduce a new one-parameter discrete distribution for the modeling of count datasets. Some mathematical properties, such as reliability measures, characteristic function, moment-generating function, and associated measurements, such as mean, variance, skewness, kurtosis, and index of dispersion, have been derived and studied. The nature of the probability mass function and failure rate function has been studied graphically. The model parameter is estimated using renowned maximum likelihood estimation methods. A neutrosophic extension of the new model is also introduced for the modeling of interval datasets. In addition, the proposed distribution's applicability was compared to that of other discrete distributions. The study's findings show that the novel discrete distribution is a very appealing alternative to some other discrete competitive distributions.

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