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1.
medRxiv ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38463998

RESUMO

The dynamics of SARS-CoV-2 transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the USA became increasingly significant. Notably, Galicia's major coastal cities emerged as critical hubs for viral transmission, highlighting their role in sustaining and spreading the virus. This research emphasizes the critical role of regional connectivity in the spread of SARS-CoV-2 and offers essential insights for enhancing public health strategies and surveillance measures.

2.
Waste Manag ; 177: 203-210, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38340568

RESUMO

Fish canning industries generate large amounts of solid waste during their processing operations, creating a significant environmental challenge. Nonetheless, this waste can be efficiently and sustainably treated through anaerobic digestion. In this study, the potential of biogas production from anaerobic digestion of thermally pretreated and co-digested solid tuna waste was investigated. The thermal pretreatment of raw fish viscera resulted in a 50 % increase in methane yield, with a production of 0.27 g COD-CH4/g COD added. However, this pretreatment did not lead to a significant increase in biogas production for cooked tuna viscera. When non-thermally pretreated raw viscera was tested, a large accumulation of volatile fatty acids and long chain fatty acids was observed, with levels reaching 21 and 6 g COD/L, respectively. On the other hand, anaerobic co-digestion of cooked tuna viscera with fat waste significantly enhanced methane production, achieving 0.87 g COD-CH4/g COD added. In contrast, co-digestion of cooked tuna viscera with dairy waste and sewage sludge resulted in notably lower yields of 0.36 and 0.46 g COD-CH4/g COD added, respectively. These results may be related to the C/N ratio, which was found to be within the optimal range for anaerobic digestion only in the tuna and fat waste co-digestion assay.


Assuntos
Biocombustíveis , Atum , Animais , Resíduos Sólidos , Metano , Esgotos , Digestão
3.
Int Braz J Urol ; 50(2): 192-198, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38386789

RESUMO

PURPOUSE: One of the many artificial intelligence based tools that has gained popularity is the Chat-Generative Pre-Trained Transformer (ChatGPT). Due to its popularity, incorrect information provided by ChatGPT will have an impact on patient misinformation. Furthermore, it may cause misconduct as ChatGPT can mislead physicians on the decision-making pathway. Therefore, the aim of this study is to evaluate the accuracy and reproducibility of ChatGPT answers regarding urological diagnoses. MATERIALS AND METHODS: ChatGPT 3.5 version was used. The questions asked for the program involved Primary Megaureter (pMU), Enuresis and Vesicoureteral Reflux (VUR). There were three queries for each topic. The queries were inserted twice, and both responses were recorded to examine the reproducibility of ChatGPT's answers. Afterwards, both answers were combined. Finally, those rwere evaluated qualitatively by a board of three specialists. A descriptive analysis was performed. RESULTS AND CONCLUSION: ChatGPT simulated general knowledge on the researched topics. Regarding Enuresis, the provided definition was partially correct, as the generic response allowed for misinterpretation. For VUR, the response was considered appropriate. For pMU it was partially correct, lacking essential aspects of its definition such as the diameter of the dilatation of the ureter. Unnecessary exams were suggested, for Enuresis and pMU. Regarding the treatment of the conditions mentioned, it specified treatments for Enuresis that are ineffective, such as bladder training. Therefore, ChatGPT responses present a combination of accurate information, but also incomplete, ambiguous and, occasionally, misleading details.


Assuntos
Enurese Noturna , Médicos , Urologia , Humanos , Inteligência Artificial , Reprodutibilidade dos Testes
4.
J Pediatr Urol ; 20(2): 222.e1-222.e8, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38195295

RESUMO

BACKGROUND: The Rome IV criteria are used to characterize constipation and its subtypes, but not its severity. Conversely, the constipation scoring system (CSS) is a tool designed to assess the level of constipation severity and assist clinicians in selecting suitable therapeutic strategies. Although validated for adults, this score has yet to be validated for children. OBJECTIVE: To adapt and validate the CSS for the pediatric population. METHODS: Children and adolescents of 4-17 years of age with no morphological or neurological abnormalities of the gastrointestinal system were randomly selected during general consultation with a pediatrician and evaluated between November 2021 to April 2022. The Rome IV criteria were considered the gold-standard detection method. The adapted version was initially assessed on 30 children to assess comprehension and then administered to another 100 children. The internal consistency of the adapted questionnaire was assessed in a test-retest procedure with a two-week interval. RESULTS: One hundred patients with a mean age of 8.61 ± 3.25 years were assessed. Of these, 51 (51 %) were male. Most children (n = 91) received a score of 1-10 (the total CSS score can range from 0 to 30 points). The correlation between the pediatric version of the CSS and the Rome IV criteria was substantial, as shown by a positive Spearman correlation (r2) of 0.553 (p < 0.001). Cronbach's alpha between the test-retest responses was 0.97. When each item of the questionnaire was assessed individually, a greater level of internal consistency was found, indicating adequate internal reliability. DISCUSSION: The current study broadens the horizon with the emergence of new diagnostic aid for FC in Brazilian children and adolescents. In addition, this study provides the cornerstone for future research to determine the diagnostic accuracy of the CSS and its prognostic value for monitoring the treatment. The loss of a follow-up rate (26 %) during the telephone "test-retest" phase was a limitation. Using a subjective questionnaire such as the Rome IV criteria as the gold standard method may also represent a limitation. Further research is required on the use of objective diagnostic tools for FC including colonic transit time, anal manometry, cine-defecography, and electromyography. CONCLUSION: The CSS was successfully adapted for use with the pediatric population and was well accepted, confirming its language and psychometric validity in aiding the diagnosis of functional constipation. This was the first step towards validating the use of this score in other countries and cultures to assess the severity of constipation in children.


Assuntos
Constipação Intestinal , Comparação Transcultural , Adulto , Adolescente , Humanos , Masculino , Criança , Pré-Escolar , Feminino , Reprodutibilidade dos Testes , Constipação Intestinal/diagnóstico , Prognóstico , Inquéritos e Questionários , Psicometria
5.
Ecotoxicol Environ Saf ; 271: 115950, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211510

RESUMO

This study investigates the use of a Yarrowia lipolytica strain for the bioconversion of syngas-derived acetic acid into ß-carotene and lipids. A two-stage process was employed, starting with the acetogenic fermentation of syngas by Clostridium aceticum, metabolising CO, CO2, H2, to produce acetic acid, which is then utilized by Y. lipolytica for simultaneous lipid and ß-carotene synthesis. The research demonstrates that acetic acid concentration plays a pivotal role in modulating lipid profiles and enhancing ß-carotene production, with increased acetic acid consumption leading to higher yields of these compounds. This approach showcases the potential of using one-carbon gases as substrates in bioprocesses for generating valuable bioproducts, providing a sustainable and cost-effective alternative to more conventional feedstocks and substrates, such as sugars.


Assuntos
Gases , Yarrowia , Dióxido de Carbono , beta Caroteno , Fermentação , Acetatos , Lipídeos
6.
Bioresour Technol ; 394: 130192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081469

RESUMO

Chain elongation technology allows medium-chain fatty acids (MCFAs) production as an alternative to fossil resources. Clostridium kluyveri generates n-caproate primarily from ethanol and acetate, presumably requiring CO2 for growth. Here, the impact of CO2 on C. kluyveri was explored. Bottle studies revealed the bacterium's adaptability to low CO2 levels, even in conditions with minimal dissolved NaHCO3 (0.0003 M) and unfavorable pH (below 6) under 1 bar CO2. Bioreactor investigations demonstrated a direct correlation between CO2 availability and bacterial growth. The highest n-caproate production (11.0 g/L) with 90.1 % selectivity was achieved in a bioreactor with continuous CO2 supply at 3 mL/min. Additional bottle experiments pressurized with 1 bar CO2 and varying ethanol:acetate ratios (1:1, 2:1, 4:1) also confirmed CO2 consumption by C. kluyveri. However, increasing the ethanol:acetate ratio did not enhance n-caproate selectivity, likely due to overly acidic pH conditions. These findings provide insights into chain-elongators responses under diverse conditions.


Assuntos
Clostridium kluyveri , Caproatos , Dióxido de Carbono , Fermentação , Reatores Biológicos , Etanol , Acetatos
7.
Travel Med Infect Dis ; 57: 102684, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38159875

RESUMO

BACKGROUND: The effectiveness of artemisinin-based combination therapies (ACT) in treating Plasmodium falciparum, is vital for global malaria control efforts, particularly in sub-Saharan Africa. The examination of imported cases from endemic areas holds implications for malaria chemotherapy on a global scale. METHOD: A 45-year-old male presented with high fever, dry cough, diarrhoea and generalized muscle pain, following a two-week trip to Mozambique. P. falciparum infection with hiperparasitemia was confirmed and the patient was treated initially with quinine and doxycycline, then intravenous artesunate. To assess drug susceptibility, ex vivo half-maximal inhibitory concentration assays were conducted, and the isolated P. falciparum genome was deep sequenced. RESULTS: The clinical isolate exhibited elevated ex vivo half-maximal inhibitory concentration values to dihydroartemisinin, lumefantrine, mefloquine and piperaquine. Genomic analysis identified a I416V mutation in the P. falciparum Kelch13 (PF3D7_1343700) gene, and several mutations at the Kelch13 interaction candidate genes, pfkics (PF3D7_0813000, PF3D7_1138700, PF3D7_1246300), including the ubiquitin carboxyl-terminal hydrolase 1, pfubp1 (PF3D7_0104300). Mutations at the drug transporters and genes linked to next-generation antimalarial drug resistance were also present. CONCLUSIONS: This case highlights the emergence of P. falciparum strains carrying mutations in artemisinin resistance-associated genes in Mozambique, couple with a reduction in ex vivo susceptibility to ACT drugs. Continuous surveillance of mutations linked to drug resistance and regular monitoring of drug susceptibility are imperative to anticipate the spread of potential resistant strains emerging in Mozambique and to maintain effective malaria control strategies.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Masculino , Humanos , Pessoa de Meia-Idade , Plasmodium falciparum , Moçambique , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Resistência a Medicamentos/genética , Mutação
8.
Sci Total Environ ; 912: 169509, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38141983

RESUMO

Megasphaera hexanoica is a bacterial strain following the reverse ß-oxidation pathway to synthesize caproate (CA) using lactate (LA) as an electron donor (ED) and acetate (AA) or butyrate (BA) as electron acceptors (EA). Differences in the type and concentration of EA lead to distinctions in product distribution and energy bifurcation of carbon fluxes in ED pathways, thereby affecting CA production. In this study, the effect of various ratios of AA, BA, and AA+BA as EA on carbon flux and CA specific titer during the carbon chain elongation in M. hexanoica was explored. The results indicated that the maximum levels of CA were 18.81 mM and 31.48 mM when the molar ratios of LA/AA and LA/BA were 10:1 and 3:1, respectively. Meanwhile, when AA and BA were used as combined EA (LA, AA, and BA molar amounts of 100, 23, and 77 mM), a maximum CA production of 39.45 mM was obtained. Further analysis revealed that the combined EA exhibited a CA production carbon flux of 49 % (4.3 % and 19.5 % higher compared to AA or BA, respectively) and a CA production specific titer of 45.24 mol (80.89 % and 58.51 % higher compared to AA or BA, respectively), indicating that the effective carbon utilization rate and CA production efficiency were greatly improved. Finally, a scaled-up experiment was conducted in a 1.2 L (working volume) automated bioreactor, implying high biomass (optical density at 600 nm or OD600 = 1.809) and a slight decrease in CA production (28.45 mM). A decrease in H2 production (4.11 g/m3) and an increase in CO2 production (0.632 g/m3) demonstrated the appropriate metabolic adaptation of M. hexanoica to environmental changes such as stirring shear.


Assuntos
Caproatos , Carbono , Elétrons , Megasphaera , Fermentação , Carbono/metabolismo , Reatores Biológicos/microbiologia , Butiratos , Acetatos
9.
Int. braz. j. urol ; 49(6): 688-699, Nov.-Dec. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550281

RESUMO

ABSTRACT Purpose: Parasacral Transcutaneous Electrical Stimulation (TENS) is one of the treatments for children with Bladder and Bowel Dysfunction (BBD). Some studies showed that children with increased Rectal Diameter (RD) have more Functional Constipation (FC). However, RD prediction in maintenance of BBD after treatment was never evaluated. Our aim is to evaluate the association between RD and response to treatment in children and adolescents with BBD. Materials and Methods: This study evaluated patients from 5-17 years old with BBD. Dysfunctional Voiding Scoring System (DVSS), Rome IV criteria, and the Constipation Score were used. RD was measured using abdominal ultrasound before treatment according to the technique established by Klijn et al. and was considered enlarged when >3cm. No laxatives were used during treatment. Descriptive analysis and binary regression were performed and the area under the ROC curve was calculated. Results: Forty children were included (mean age 8.4±2.8 years, 52.5% male). Before treatment, RD was enlarged in 15 children (37.5%) (mean diameter 3.84±0.6cm), with FC persisting post-treatment in 11/15(73.3%). Those patients also required more laxatives following treatment and had more severe FC. Binary regression showed pretreatment RD to be an independent predictor of the persistence of FC post-treatment (OR=9.56; 95%CI:2.05-44.60). In ROC curve analysis, the sensitivity was 100% (95%CI: 0.49-1.0) and specificity 77.14% (95%CI:0.60-0.90) for rectal diameter >3 cm. The likelihood ratio was 4.38 (95%CI:2.40-8.0) for the persistence of BBD following treatment. Conclusion: RD appears to be relevant in the evaluation of children with BBD, not only as a diagnostic tool but also as a predictor of treatment outcome.

10.
Rev. enferm. UERJ ; 31: e71679, jan. -dez. 2023.
Artigo em Inglês, Português | LILACS-Express | LILACS | ID: biblio-1444020

RESUMO

Objetivo: compreender os fatores que interferem no diagnóstico da sífilis em homens à luz da Teoria da Diversidade e Universalidade do Cuidado Cultural. Método: estudo qualitativo, aprovado por Comitê de Ética em Pesquisa, realizado em Hospital Universitário no Rio de Janeiro, entre setembro de 2017 e março de 2018. Foram entrevistados 32 homens diagnosticados com sífilis adquirida, e a análise temática foi utilizada para o tratamento dos dados. Resultados: a maioria dos homens tinha história de contágio por outra Infecção Sexualmente Transmissível e foi diagnosticada no ambulatório de imunologia. O momento diagnóstico é encarado com surpresa, tem repercussões psicossociais e é influenciado por fatores culturais e sociais. Considerações finais: alguns fatores interferem positivamente e outros negativamente no diagnóstico da sífilis na população masculina. Para detectar essa infecção nos homens, deve-se conhecer o contexto sociocultural em que estão inseridos para, assim, implementar estratégias tanto diagnósticas quanto preventivas mais eficazes.


Objective: to understand the factors that interfere with the diagnosis of syphilis in men in the light of the Theory of Diversity and Universality of Cultural Care. Method: qualitative study, approved by the Ethics and Research Committee, conducted at a University Hospital in Rio de Janeiro, during september 2017 to march 2018. Thirty-two men diagnosed with acquired syphilis were interviewed, and thematic analysis was used for data treatment. Results: most men had a history of contagion by another STI and were diagnosed at the immunology outpatient clinic. The moment of diagnosis is faced with surprise, has psychosocial repercussions and is influenced by cultural and social factors. Final considerations: some factors interfere positively and others negatively in the diagnosis of syphilis in the male population. To detect this infection in men, it is necessary to know the sociocultural context in which they live, in order to implement more effective diagnostic and preventive strategies.


Objetivo: comprender los factores que interfieren en el diagnóstico de la sífilis en los hombres a la luz de la Teoría de la diversidad y universalidad del cuidado cultural. Método: estudio cualitativo, aprobado por el Comité de Ética en Investigación, realizado en un Hospital Universitario de Río de Janeiro, de septiembre de 2017 a marzo de 2018. Se entrevistó a 32 hombres diagnosticados de sífilis adquirida y se utilizó el análisis temático para el tratamiento de los datos. Resultados: la mayoría de los hombres tenía antecedentes de contagio por otra Infección Sexualmente Transmisible y el diagnóstico se hizo en el ambulatorio de inmunología. El momento del diagnóstico se afronta con sorpresa, tiene repercusiones psicosociales y está influenciado por factores culturales y sociales. Consideraciones finales: algunos factores interfieren positivamente y otros negativamente en el diagnóstico de la sífilis en la población masculina. Para detectar esta infección en los hombres, se debe conocer el contexto sociocultural en el que se insertan, para entonces poner en marcha estrategias de diagnóstico y de prevención más eficaces.

11.
Front Microbiol ; 14: 1281103, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029098

RESUMO

Introduction: Chain elongation technology, which involves fermentation with anaerobic bacteria, has gained attention for converting short and medium chain substrates into valuable and longer-chain products like medium chain fatty acids (MCFAs). In the recent past, the focus of studies with pure chain elongating cultures was on species of other genera, mainly Clostridium kluyveri. Recently, other chain elongators have been isolated that deserve further research, such as Megasphaera hexanoica. Methods: In this study, batch studies were performed in bottles with two different media to establish the optimal conditions for growth of M. hexanoica: (a) a medium rich in different sources of nitrogen and (b) a medium whose only source of nitrogen is yeast extract. Also, batch bioreactor studies at pH values of 5.8, 6.5 and 7.2 were set up to study the fermentation of lactate (i.e., electron donor) and acetate (i.e., electron acceptor) by M. hexanoica. Results and discussion: Batch bottle studies revealed the yeast extract (YE) containing medium as the most promising in terms of production/cost ratio, producing n-caproate rapidly up to 2.62 ± 0.24 g/L. Subsequent bioreactor experiments at pH 5.8, 6.5, and 7.2 confirmed consistent production profiles, yielding C4-C8 fatty acids. A fourth bioreactor experiment at pH 6.5 and doubling both lactate and acetate concentrations enhanced MCFA production, resulting in 3.7 g/L n-caproate and 1.5 g/L n-caprylate. H2 and CO2 production was observed in all fermentations, being especially high under the increased substrate conditions. Overall, this study provides insights into M. hexanoica's behavior in lactate-based chain elongation and highlights optimization potential for improved productivity.

12.
Int Braz J Urol ; 49(6): 688-699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37903006

RESUMO

PURPOSE: Parasacral Transcutaneous Electrical Stimulation (TENS) is one of the treatments for children with Bladder and Bowel Dysfunction (BBD). Some studies showed that children with increased Rectal Diameter (RD) have more Functional Constipation (FC). However, RD prediction in maintenance of BBD after treatment was never evaluated. Our aim is to evaluate the association between RD and response to treatment in children and adolescents with BBD. MATERIALS AND METHODS: This study evaluated patients from 5-17 years old with BBD. Dysfunctional Voiding Scoring System (DVSS), Rome IV criteria, and the Constipation Score were used. RD was measured using abdominal ultrasound before treatment according to the technique established by Klijn et al. and was considered enlarged when >3cm. No laxatives were used during treatment. Descriptive analysis and binary regression were performed and the area under the ROC curve was calculated. RESULTS: Forty children were included (mean age 8.4±2.8 years, 52.5% male). Before treatment, RD was enlarged in 15 children (37.5%) (mean diameter 3.84±0.6cm), with FC persisting post-treatment in 11/15(73.3%). Those patients also required more laxatives following treatment and had more severe FC. Binary regression showed pretreatment RD to be an independent predictor of the persistence of FC post-treatment (OR=9.56; 95%CI:2.05-44.60). In ROC curve analysis, the sensitivity was 100% (95%CI: 0.49-1.0) and specificity 77.14% (95%CI:0.60-0.90) for rectal diameter >3 cm. The likelihood ratio was 4.38 (95%CI:2.40-8.0) for the persistence of BBD following treatment. CONCLUSION: RD appears to be relevant in the evaluation of children with BBD, not only as a diagnostic tool but also as a predictor of treatment outcome.


Assuntos
Estimulação Elétrica Nervosa Transcutânea , Doenças da Bexiga Urinária , Humanos , Criança , Masculino , Adolescente , Pré-Escolar , Feminino , Estimulação Elétrica Nervosa Transcutânea/métodos , Bexiga Urinária/diagnóstico por imagem , Constipação Intestinal/terapia , Constipação Intestinal/diagnóstico , Resultado do Tratamento
13.
Bioresour Technol ; 390: 129880, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37852509

RESUMO

The environmental concerns regarding fossil plastics call for alternative biopolymers such as polyhydroxyalkanoates (PHAs) whose manufacturing costs are however still too elevated. Autotrophic microbes like Cupriavidus necator, able to convert CO2 and H2 into PHAs, offer an additional strategy. Typically, the preferred source for CO2 and H2 are expensive pure gases or syngas, which has toxic compounds for most PHAs-accumulating strains. In this work, for the first time, H2 and CO2 originating from an acidogenic reactor were converted autotrophically into poly(3-hydroxybutyrate) P(3HB). During the first stage, a mixed microbial community continuously catabolized melon waste into H2 (26.7 %) and CO2 (49.2 %) that were then used in a second bioreactor by C. necator DSM 545 to accumulate 1.7 g/L P(3HB). Additionally, the VFAs (13 gCOD/L) produced during acidogenesis were processed into 2.7 g/L of P(3HB-co-3HV). This is the first proof-of-concept of using acidogenic-derived H2 and CO2 from fruit waste to produce PHAs.


Assuntos
Cupriavidus necator , Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Dióxido de Carbono , Fermentação , Frutas/metabolismo , Reatores Biológicos , Cupriavidus necator/metabolismo
14.
Bioresour Technol ; 389: 129815, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37783238

RESUMO

An engineered Yarrowia lipolytica strain was successfully employed to produce ß-carotene and lipids from acetic acid, a product of syngas fermentation by Clostridium aceticum. The strain showed acetic acid tolerance up to concentrations of 20 g/L. Flask experiments yielded a peak lipid content of 33.7 % and ß-carotene concentration of 13.6 mg/g under specific nutrient conditions. The study also investigated pH effects on production in bioreactors, revealing optimal lipid and ß-carotene contents at pH 6.0, reaching 22.9 % and 44 mg/g, respectively. Lipid profiles were consistent across experiments, with C18:1 being the dominant compound at approximately 50 %. This research underscores a green revolution in bioprocessing, showing how biocatalysts can convert syngas, a potentially polluting byproduct, into valuable ß-carotene and lipids with a Y. lipolytica strain.


Assuntos
Yarrowia , Fermentação , Yarrowia/genética , beta Caroteno , Lipídeos , Acetatos
15.
Chemosphere ; 341: 140022, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657695

RESUMO

A gaseous mixture of methanol (M), α-pinene (P), and hydrogen sulfide (H) was treated in one/two-liquid phase biotrickling filters (OLP/TLP-BTFs) at varying inlet concentrations and at an empty bed residence time (EBRT) of 57 s. The performance of TLP-BTF [BTF (A)] improved significantly in terms of M and P removal due to the presence of silicone oil at 5% v/v. The maximum elimination capacities (ECs) of M, P, and H in BTF (A) were obtained as 309, 73, and 56 g m-3 h-1, respectively. While, the maximum ECs achieved in the BTF operated without silicone oil [BTF (B)] were 172, 28, and 21 g m-3 h-1 for M, P, and H removal, respectively. Increasing the inlet concentration of H from 32 to 337 ppm inhibited P removal in both the BTFs. The presence of silicone oil enhanced gas-liquid mass transfer, prevented the BTF from experiencing substrate inhibition effects and allowed reaching high ECs for M and P. The experiments showed promising results for the long-term operation of removal of M, P, and H mixture in a one-stage TLP-BTF with the decreasing negative effects of M and H on P degradation.


Assuntos
Poluentes Atmosféricos , Sulfeto de Hidrogênio , Metanol , Óleos de Silicone , Reatores Biológicos , Filtração/métodos , Gases , Biodegradação Ambiental
16.
J Environ Manage ; 347: 119097, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776787

RESUMO

Syngas (CO, CO2, H2) was effectively bioconverted into lipids in a two-stage process. In the first stage, C1-gases were bioconverted into acetic acid by the acetogenic species Clostridium aceticum through the Wood-Ljungdahl metabolic pathway in a stirred tank bioreactor, reaching a maximum acetic acid concentration of 11.5 g/L, with a production rate of 0.05 g/L·h. Throughout this experiment, samples were extracted at different periods, i.e., different concentrations, to be used in the second stage, aiming at the production of lipids from acetic acid. The yeast Rhodosporidium toruloides, inoculated in the acetogenic medium, was able to efficiently accumulate lipids from acetic acid generated in the first stage. The best results, in terms of lipid content, dry biomass, biomass yield (Y(X/S)) and lipid yield (Y(L/S)) were 39.5% g/g dry cell weight, 3 g/L, 0.35 and 0.107, respectively. In terms of abundance, the lipid profile followed the order: C18:1 > C16:0 > C18:2 > C18:0 > Others. Experiments were also performed to determine the toxicity exerted by high concentrations of acetic acid on R. toruloides, resulting in inhibition at initial acid concentrations around 18 g/L leading to a higher lag phase and being lethal to the yeast at initial acetic acid concentrations around 22 g/L and above. This research paves the way for a novel method of growing oleaginous yeasts to produce sustainable biofuels from syngas or C1-pollutant gases.


Assuntos
Ácidos Carboxílicos , Gases , Dióxido de Carbono , Ácido Acético/metabolismo , Biocombustíveis , Biomassa
17.
Environ Res ; 237(Pt 2): 116978, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633629

RESUMO

The performance of one- and two-liquid phase biotrickling filters (OLP/TLP-BTFs) treating a mixture of gas-phase methanol (M), α-pinene (P), and hydrogen sulfide (H) was assessed using artificial neural network (ANN) modeling. The best ANN models with the topologies 3-9-3 and 3-10-3 demonstrated an exceptional capacity for predicting the performance of O/TLP-BTFs, with R2 > 99%. The analysis of causal index (CI) values for the model of OLP-BTF revealed a negative impact of M on P removal (CI = -2.367), a positive influence of P and H on M removal (CI = +7.536 and CI = +3.931) and a negative effect of H on P removal (CI = -1.640). The addition of silicone oil in TLP-BTF reduced the negative impact of M and H on P degradation (CI = -1.261 and CI = -1.310, respectively) compared to the OLP-BTF. These findings suggested that silicone oil had the potential to improve P availability to the biofilm by increasing the concentration gradient of P between the air/gas and aqueous phases. Multi-objective particle swarm optimization (MOPSO) suggested an optimum operational condition, i.e. inlet M, P, and H concentrations of 1.0, 1.1, and 0.3 g m-3, respectively, with elimination capacities (ECs) of 172.1, 26.5, and 0.025 g m-3 h-1 for OLP-BTF. Likewise, one of the optimum operational conditions for TLP-BTF is achievable at inlet concentrations of 4.9, 1.7, and 0.8 g m-3, leading to the optimum ECs of 299.7, 52.9, and 0.072 g m-3 h-1 for M, P, and H, respectively. These results provide important insights into the treatment of complex waste gas mixtures, addressing the interactions between the pollutant removal characteristics in OLP/TLP-BTFs and providing novel approaches in the field of biological waste gas treatment.

18.
Biotechnol Biofuels Bioprod ; 16(1): 96, 2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37270640

RESUMO

Carboxylic acids have become interesting platform molecules in the last years due to their versatility to act as carbon sources for different microorganisms or as precursors for the chemical industry. Among carboxylic acids, short-chain fatty acids (SCFAs) such as acetic, propionic, butyric, valeric, and caproic acids can be biotechnologically produced in an anaerobic fermentation process from lignocellulose or other organic wastes of agricultural, industrial, or municipal origin. The biosynthesis of SCFAs is advantageous compared to chemical synthesis, since the latter relies on fossil-derived raw materials, expensive and toxic catalysts and harsh process conditions. This review article gives an overview on biosynthesis of SCFAs from complex waste products. Different applications of SCFAs are explored and how these acids can be considered as a source of bioproducts, aiming at the development of a circular economy. The use of SCFAs as platform molecules requires adequate concentration and separation processes that are also addressed in this review. Various microorganisms such as bacteria or oleaginous yeasts can efficiently use SCFA mixtures derived from anaerobic fermentation, an attribute that can be exploited in microbial electrolytic cells or to produce biopolymers such as microbial oils or polyhydroxyalkanoates. Promising technologies for the microbial conversion of SCFAs into bioproducts are outlined with recent examples, highlighting SCFAs as interesting platform molecules for the development of future bioeconomy.

19.
IEEE Trans Biomed Eng ; 70(8): 2318-2328, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37022426

RESUMO

OBJECTIVES: Optical spectrophotometry has been explored to quantify Plasmodium falciparum malaria parasites at low parasitemia, with potential to overcome the limitations of detection in the current diagnostic methods. This work presents the design, simulation and fabrication of a CMOS microelectronic detection system to automatically quantify the presence of malaria parasites in a blood sample. METHODS: The designed system is composed by an array of 16 n+/p-substrate silicon junction photodiodes as photodetectors and 16 current to frequency (IF) converters. An optical setup was used to individually and jointly characterize the entire system. RESULTS: The IF converter was simulated and characterized in Cadence Tools using UMC 1180 MM/RF technology rules, featuring a resolution of 0.01 nA, a linearity up to 1800 nA and a sensitivity of 4430 Hz/nA. After fabrication in a silicon foundry, the photodiodes' characterization presented a responsivity peak of 120 mA/W (λ = 570 nm) and a dark current of 7.15 pA at 0 V. Regarding the IF converter, it exhibited high linearity (R2 ≈ 0.999) up to 30 nA, with a sensitivity of 4840 Hz/nA. Furthermore, the microsystem performance was validated using RBCs (Red Blood Cells) infected with P. falciparum and diluted at different parasitemia (12, 25 and 50 parasites/µL). CONCLUSION: The microsystem was able to distinguish between healthy and infected RBCs, with a sensitivity of 4.5 Hz/parasites.µL-1. SIGNIFICANCE: The developed microsystem presents a competitive result, when compared to the gold standard diagnosis methods, with increased potential for malaria in field diagnosis.


Assuntos
Malária Falciparum , Malária , Humanos , Plasmodium falciparum , Silício , Parasitemia/diagnóstico , Parasitemia/parasitologia , Malária/diagnóstico , Malária Falciparum/diagnóstico , Malária Falciparum/parasitologia , Espectrofotometria , Sensibilidade e Especificidade
20.
Cells ; 12(7)2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-37048057

RESUMO

Neural injuries in cerebral malaria patients are a significant cause of morbidity and mortality. Nevertheless, a comprehensive research approach to study this issue is lacking, so herein we propose an in vitro system to study human cerebral malaria using cellular approaches. Our first goal was to establish a cellular system to identify the molecular alterations in human brain vasculature cells that resemble the blood-brain barrier (BBB) in cerebral malaria (CM). Through transcriptomic analysis, we characterized specific gene expression profiles in human brain microvascular endothelial cells (HBMEC) activated by the Plasmodium falciparum parasites. We also suggest potential new genes related to parasitic activation. Then, we studied its impact at brain level after Plasmodium falciparum endothelial activation to gain a deeper understanding of the physiological mechanisms underlying CM. For that, the impact of HBMEC-P. falciparum-activated secretomes was evaluated in human brain organoids. Our results support the reliability of in vitro cellular models developed to mimic CM in several aspects. These systems can be of extreme importance to investigate the factors (parasitological and host) influencing CM, contributing to a molecular understanding of pathogenesis, brain injury, and dysfunction.


Assuntos
Malária Cerebral , Humanos , Malária Cerebral/metabolismo , Malária Cerebral/parasitologia , Malária Cerebral/patologia , Células Endoteliais/metabolismo , Reprodutibilidade dos Testes , Encéfalo/patologia , Plasmodium falciparum , Organoides/metabolismo
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