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1.
Future Oncol ; : 1-9, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39129675

RESUMO

The SWI/SNF complex is a chromatin remodeling complex comprised by several proteins such as SMARCA4 or SMARCB1. Mutations in its components can lead to the development of aggressive rhabdoid tumors such as epithelioid sarcoma, malignant rhabdoid tumor or small cell carcinoma of the ovary hypercalcemic type, among others. These malignancies tend to affect young patients and their prognosis is poor given the lack of effective treatments. Characteristically, these tumors are highly infiltrated by TILs, suggesting that some lymphocytes are recognizing tumor antigens. The use of those TILs as a therapeutic strategy is a promising approach worth exploring. Here, we report the clinical protocol of the TILTS study, a Phase II clinical trial assessing personalized adoptive cell therapy with TILs in patients affected by these tumor types.Clinical Trial Registration: 2023-504632-17-00 (www.clinicaltrialsregister.eu) (ClinicalTrials.gov).


[Box: see text].

2.
Environ Res ; 255: 119166, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38759772

RESUMO

Pseudomonas aeruginosa belong to the special pathogen group capable of causing serious infections, with high mortality rates. The aim of this study was to describe the antibiotic resistance and genomic characteristics of Pseudomonas aeruginosa belonging to international high-risk clone ST235 (GPAE0131 isolate), obtained from hospital wastewater. P. aeruginosa GPAE0131 was isolated from ward tertiary hospital in Brazil and the antibiotic resistance profile was determined by the disc-diffusion method. Genomic characteristics related to antibiotic resistance and virulence factors were evaluated by genomic DNA sequencing on the Illumina MiSeq platform and bioinformatic analysis. GPAE0131 isolate showed resistance to piperacillin-tazobactam, cefepime, ceftazidime, imipenem, meropenem, ciprofloxacin, levofloxacin and tobramycin. Resistome comprehend of resistance genes to ß-lactams (blaVIM-2, blaOXA-4, blaOXA-488, blaPDC-35), aminoglycosides (aph(3')-IIb, aac(6')-IIc, aac(6')-Ib9, aadA1), fosfomycin (fosA), chloramphenicol (catB7) and sulfonamides (sul1). Genome comparisons evidence insertion of blaVIM-2 and blaOXA-4 genes. GPAE0131 isolate was predicted to be pathogenic to humans and several virulence factors were found, including encoding gene for ExoU and exotoxin A. All of these features into a pathogenic international high-risk clone (ST235), classified as critical priority, stands out as public health concern due to the widespread dispersal of human pathogens through wastewater. It is suggested that mitigating measures be implemented, such as the treatment of hospital sewage and the addition of tertiary treatment, to prevent the escape of pathogens at this level into the environment.


Assuntos
Pseudomonas aeruginosa , Águas Residuárias , Águas Residuárias/microbiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Humanos , Brasil , Antibacterianos/farmacologia , Hospitais , beta-Lactamases/genética , Fatores de Virulência/genética , Genômica
3.
Rev Med Chil ; 152(1): 36-48, 2024 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-39270095

RESUMO

INTRODUCTION: The COVID-19 pandemic marked a milestone in the history of medicine worldwide. Together with the humanitarian drama it represented, the problems that arose are promoting lines of research in multiple fields. One of these fields is the aspects related to medical communication and end-of-life care. This paper reports the experiences and perceptions of relatives of patients who died during the pandemic with a psychospiritual support intervention in a public hospital in the Metropolitan Region, Chile, called "farewell". METHODS: A qualitative study was conducted with a phenomenological approach based on in-depth interviews. From this, categories were derived that allowed a systematization of the observation of the experiences. RESULTS: Among the results, the impact of the circumstances and the communication provided by the medical team on grief should be highlighted. The use of the word "farewell" emerges as a useful, albeit ambiguous, communicative tool when it comes to adequately framing an end-of-life process. CONCLUSIONS: It is argued that the end of life is an area that requires physical and psychospiritual spaces, and adequate training at all levels to do justice to a highly relevant moment in the care of people.


Assuntos
COVID-19 , Família , Pesquisa Qualitativa , Assistência Terminal , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Chile/epidemiologia , Família/psicologia , Assistência Terminal/psicologia , Masculino , Feminino , SARS-CoV-2 , Atitude Frente a Morte , Adulto , Pandemias , Pessoa de Meia-Idade , Pesar , Entrevistas como Assunto , Idoso , Comunicação
4.
Fish Shellfish Immunol ; 140: 108975, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37488040

RESUMO

The parr-smolt transformation in salmonids involves a critical period characterized by systemic changes associated with the fish's immune response. In this context, as a dietary ingredient in functional diets, microalgae offer an alternative due to their nutritional and bioactive compounds that could strengthen the immune status. This study evaluated the effect of a diet supplemented with Schizochytrium spp and Nannochloropsis gaditana on the expression of genes associated with the antibacterial response. Additionally, the study assessed the effect on the leukocyte population and erythrocyte maturity in Salmo salar blood. Fish were fed for 30 days with a microalgal mixture (1:1) at a 10% inclusion. Each diet was randomly assigned to a tank using a completely randomized design (CRD) with four replications. Each tank was stocked with 70 Atlantic salmon fingerlings with an initial mean weight of 78.87 ± 0.84. Transcription levels were quantified and analyzed by qRT-PCR from cell isolates and mucus tissue. Furthermore, cell count and identification of leukocytes and classification of cellular maturity of erythrocytes using a neural network with a multilayer perceptron (MLP) were performed. Our results showed a significant (p < 0.05) increase in fold change expression of C3 (2.54 ± 0.65) and NK-Lysine (6.84 ± 0.94) in erythrocytes of microalgae-supplemented fish. Moreover, a significant increase of 1.59 and 2.35 times in monocytes and immature erythrocytes, respectively, was observed in the same group of fish (p < 0.05). This study's results indicate that dual microalgae (Schizochytrium spp and N. gaditana) supplementation can increase innate humoral antibacterial components, particularly in erythrocyte tissue, and increase phagocytic cells and immature erythrocytes in S. salar blood.


Assuntos
Microalgas , Salmo salar , Estramenópilas , Animais , Dieta/veterinária , Imunidade Inata , Eritrócitos , Antibacterianos , Ração Animal/análise
5.
Environ Res ; 233: 116443, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37356524

RESUMO

Among the ESKAPE group pathogens, Enterobacter spp. is an opportunistic Gram-negative bacillus, widely dispersed in the environment, that causes infections. In the present study, samples of hospital wastewater, raw and treated urban wastewater, as well as surface receiving water, were collected to assess the occurrence of multidrug-resistant (MDR) Enterobacter spp. A molecular characterization of ß-lactam antibiotic resistance and metal tolerance genes was performed. According to identification by MALDI-TOF MS, 14 isolates were obtained: 7 E. bugandensis, 5 E. kobei, and 2 E. cloacae. The isolates showed resistance mainly to ß-lactam antibiotics, including those used to treat infections caused by MDR bacteria. Multiple antibiotic resistance index was calculated for all isolates. It allowed verify whether sampling points showed a high risk due to antibiotic resistant Enterobacter spp., as well as to determine if the isolates have been in environments with a frequent antibiotic use. Twelve isolates showed ß-lactam antibiotic resistance gene, being the blaKPC widely detected. Regarding metal tolerance, 13 isolates showed at least two genes that encode metal tolerance mechanisms. Overall, metal tolerance mechanisms to silver, copper, mercury, arsenic and tellurium were found. New data on metal tolerance mechanisms dispersion and antibiotic-resistance characterization of the E. bugandensis and E. kobei species were here provided. The occurrence of MDR Enterobacter spp. in analyzed samples draws attention to an urgent need to put control measures into practice. It also evidences waterborne spread of clinically important antibiotic-resistant bacteria recognized as critical priority pathogens.


Assuntos
Enterobacter , Águas Residuárias , Enterobacter/genética , Resistência beta-Lactâmica , Antibacterianos/farmacologia , beta-Lactamas/farmacologia , beta-Lactamases/genética , Testes de Sensibilidade Microbiana
6.
Environ Monit Assess ; 194(6): 407, 2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35524884

RESUMO

Gastrointestinal diseases caused by protozoan parasites remain a major challenge in developing countries and ingestion of contaminated surface water represents one of the main sources by which these diseases are contracted. This study assessed the risk of infection and diseases caused by Cryptosporidium spp. and Giardia sp. due to ingestion of surface water used for public supply and recreational activities, focusing on the southeastern Brazilian Pardo River and applying the USEPA 1623 method to quantify (oo)cyst concentrations. Infection and disease probabilities due to ingestion of drinking water or during recreational activities were estimated using the Quantitative Microbial Risk Assessment (QMRA) approach. Mean concentrations of Cryptosporidium spp. and Giardia sp. in surface water ranged from 0.2 to 0.4 oocysts L-1 and 0.2 to 4.4 cysts L-1, respectively. Considering public water supply, annual infection probabilities were higher for adults than children and exceeded the USEPA limit; also, disease probabilities were higher for adults than children. For recreational activities, annual infection and disease probabilities were higher for children, followed by men and women. The occurrence of both parasites likely reflects raw sewage discharge, effluent from sewage treatment plants, and diffuse sources of pollution, such as runoff from pasture lands and deforested riparian forest corridors. Our results highlight substantial infection risks by both parasite types after conventional treatment of water used for public supply and also call for careful monitoring of water bodies used for recreational purposes.


Assuntos
Criptosporidiose , Cryptosporidium , Água Potável , Parasitos , Animais , Criança , Criptosporidiose/epidemiologia , Água Potável/parasitologia , Monitoramento Ambiental/métodos , Feminino , Giardia , Humanos , Oocistos , Medição de Risco , Esgotos/parasitologia , Abastecimento de Água
7.
Ann Surg Oncol ; 28(13): 8979-8986, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34091804

RESUMO

OBJECTIVES: Enhanced Recovery After Surgery (ERAS) programs include multiple perioperative care elements, which when implemented together are designed to improve recovery after surgery with subsequent reduction in hospital length of stay (LOS). The aim of this study is to examine the impact of ERAS protocol compliance on LOS in patients undergoing advanced ovarian cancer surgery within the context of a randomized clinical trial. METHODS: Patients were enrolled in a prospective, consecutive, interventional randomized clinical trial between June 2014 and March 2018. Women with either suspected or confirmed advanced ovarian cancer with International Federation of Gynecology and Obstetrics (FIGO) stages IIB-IVA and recurrent ovarian cancer, who underwent cytoreduction surgery, were randomly assigned to either a conventional management (CM) protocol or an ERAS protocol. Demographic items, preoperative clinical data, and surgical characteristics of patients were recorded, as were LOS and ERAS protocol compliance. Negative binomial regression was used to model the relation between length of stay and ERAS protocol compliance. RESULTS: We included 49 patients in the CM group and 50 patients in the ERAS group. The overall rate of ERAS compliance was 92%. We observed that increasing ERAS protocol compliance was associated with shorter median LOS, and in patients who underwent higher complex surgeries, the length of stay reduction was greater. CONCLUSION: This study identifies a correlation between increasing ERAS protocol compliance and decreasing LOS in ovarian cancer surgery. This finding underlines the necessity to implement as many ERAS protocol elements as possible to achieve optimal clinical outcome improvements.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Neoplasias Ovarianas , Feminino , Fidelidade a Diretrizes , Humanos , Tempo de Internação , Recidiva Local de Neoplasia/cirurgia , Neoplasias Ovarianas/cirurgia , Estudos Prospectivos
8.
Environ Res ; 196: 110352, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33098821

RESUMO

Some heavy metals have antimicrobial activity and are considered as potential alternatives to traditional antibiotic therapy. However, heavy metal tolerance genes (HMTG) have been already detected and coding different tolerance mechanisms. Considering that certain metals are promising for antimicrobial therapy, evaluation of HMTG dissemination in bacteria from sewage is essential to understand the evolution of these bacteria and to predict antimicrobial use and control. The present study aimed to evaluate the occurrence of bacteria carrying HMTG in samples of hospital wastewater and from urban wastewater treatment plant (WWTP). The acquired HMTG were investigated by PCR in bacterial collection previously characterized for antibiotic resistant genes (ARGs). HMTG searched include arsB (arsenic efflux pump), czcA (cadmium, zinc and cobalt efflux pump), merA (mercuric reductase), pcoD (copper efflux pump), silA (silver efflux pump) and terF (tellurite resistance protein). Among 45 isolates, 82% of them carried at last one HMTG, in which the silA and pcoD tolerance genes were the most prevalent. A very strong positive correlation was found between these genes (r = 0.91, p < 0.0001). Tolerance genes merA, arsB, czcA and terF were detected in 47%, 13%, 13% and 7% of the isolates, respectively. It was found that 15 isolates co-harbored ARGs (ß-lactamase encoding genes). HMTG are probably more dispersed than ARGs in bacteria, representing a new concern for heavy metals use as effective antimicrobials. To the best of our knowledge, this is the first study on the HMTG searched in Hafnia alvei, Serratia fonticola and Serratia liquefaciens. Hospital wastewater treatment implementation and additional technologies for treatment in WWTP can reduce the impacts on water resources and HMTG spread, ensureing the environmental and human health safety.


Assuntos
Metais Pesados , Águas Residuárias , Antibacterianos , Genes Bacterianos , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Serratia
9.
Environ Res ; 188: 109733, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32574850

RESUMO

Concentrated human milk (HM-concentrate) can be obtained from the simple and inexpensive method of donated breast milk direct lyophilization. A previous study reported that HM-concentrate contains the adequate amount of main macro- and micronutrients for use as a nutritional resource for preterm infants with very low birth weight admitted to neonatal intensive care units. However, further details need to be elucidated about HM-concentrate composition, particularly its content of essential and potentially toxic trace elements. Therefore, this study aimed to determine the concentration of essential and toxic elements in human milk considered baseline (HM-baseline) and HM-concentrate, as well as to quantify changes in concentration of these elements after the HM concentration process. The concentration of Aluminum, Arsenic, Cadmium, Chromium, Iron, Mercury, Manganese, Nickel, Lead, Selenium, Tin, and Thallium was analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). Moreover, Bayesian linear mixed effect models were applied to estimate the mean difference between HM-baseline and HM-concentrate samples. After comparison (HM-concentrate versus HM-baseline), a significant increase in concentration was observed only for Manganese (0.80 µg/L; 95% CrI [0.16; 1.43]) and Selenium (6.74 µg/L; 95% CrI [4.66; 8.86]), while Lead concentration (-6.13 µg/L; 95% CrI [-8.63; -3.61]) decreased. This study provides latest and reliable information about HM composition. After milk concentration by lyophilization, there was a significant increase only in the essential elements Manganese and Selenium. The essential micronutrient content in HM-concentrate was similar or higher than that in preterm mothers' milk, which suggests it is viable for nutritional support of preterm infants. In addition, the low concentrations of potentially toxic elements in HM-concentrate indicates that it is safe for consumption by premature newborns.


Assuntos
Leite Humano , Oligoelementos , Animais , Teorema de Bayes , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Leite Humano/química , Oligoelementos/análise
10.
Molecules ; 25(20)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050537

RESUMO

Omega-3 long-chain polyunsaturated fatty acids (n-3 LC PUFAs) and vitamin D3 are essential components of human nutrition. A regular human diet is highly deficient in n-3 LC PUFAs. Fish like salmon are highly recommended in the human diet as they are a major source of high-value n-3 LC PUFAs and vitamin D3. The levels of these nutrients have been decreasing over the last few years in farmed salmon, whose production urgently needs sustainable sources of these nutrients. The microalga Nannochloropsis gaditana (NG) is known for its naturally high potential for the production of eicosapentaenoic (EPA, 20:5 n-3) fatty acid. A commercial diet for Atlantic salmon was supplemented with 1% and 10% of spray-dried NG grown under controlled conditions for a high EPA content. Salmon were harvested on day 49, following which, boneless and skinless salmon meat was recovered from fish and analyzed for the fatty acid profile, total fat, and vitamin D3. Vitamin D3, EPA, and docosapentaenoic fatty acid (DPA, 22:5 n-3) levels were significantly increased (p < 0.05) by supplementing the basal diet with 10% NG, thus, NG represents a novel, functional, natural ingredient and a sustainable source of n-3 LC-PUFAs that can raise the levels of healthy fats and vitamin D3 in farmed salmon meat.


Assuntos
Colecalciferol/análise , Ácido Eicosapentaenoico/análise , Ácidos Graxos Insaturados/análise , Microalgas/química , Salmo salar/metabolismo , Animais , Humanos
11.
Environ Monit Assess ; 192(6): 376, 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32417981

RESUMO

Multidrug resistance mediated by ß-lactamase in Gram-negative bacilli is a serious public health problem. Sewers are considered reservoirs of multiresistant bacteria due to presence of antibiotics that select them and favor their dissemination. The present study evaluated the antibiotic resistance profile and ß-lactamases production in Gram-negative bacilli isolates from hospital sewage and urban wastewater treatment plants (UWWTP) in Brazil. Bacteria were isolated and identified with biochemical tests. Antibiotic susceptibility testing was performed by the disk-diffusion method and detection of extended-spectrum ß-lactamase and carbapenemases by enzymatic inhibitor and conventional PCR. Differences in resistance to amoxicillin clavulanic, aztreonam, cefepime, and cefotaxime were observed in hospital sewage compared with urban sewage (p < 0.05). The multidrug-resistant phenotype was observed in 33.3% of hospital sewage isolates (p = 0.0025). ß-lactamases genes were found in 35.6% of isolates, with the most frequent being blaKPC and blaTEM (17.8%), and blaSHV and blaCTX-M (13.3% and 8.9%, respectively). The data obtained are relevant, since the bacteria detected are on the priority pathogens list from the World Health Organization and hospital sewage could be released untreated into the municipal collection system, which may favor the spread of resistance. Changes in hospital sewage discharge practices, as well as additional technologies regarding effluent disinfection in the UWWTP, can prevent the spread of these bacteria into the environment and negative impact on water resources.


Assuntos
Monitoramento Ambiental , Bactérias Gram-Negativas , Eliminação de Resíduos de Serviços de Saúde , Águas Residuárias , beta-Lactamases , Antibacterianos , Brasil , Cidades , Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/genética , Hospitais , Testes de Sensibilidade Microbiana
12.
Aust N Z J Fam Ther ; 41(2): 114-132, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32836731

RESUMO

The COVID-19 pandemic has convulsed human communities across the globe like no previous event in history. Family therapists, paradoxically, given the core of their work is with systems, are also experiencing upheaval in professional and personal lives, trying to work amidst a society in chaos. This paper offers a collection of reflections by systemic and family therapists from diverse cultures and contexts penned in the midst of the pandemic. The main intention in distilling these narratives is to preserve the 'cultural diversity' and 'ecological position' of the contributors, guided by phenomenology, cultural ecology, and systemic worldviews of 'experiencing.' The second intention is to 'unite' promoting solidarity in this isolating situation by bringing each story together, creating its own metaphor of a family: united, connected, stronger. As a cross-cultural family practitioner, with a strong mission for collaboration, the lead author acknowledges the importance of Context - the nation and location of the experience; Culture - the manner in which culture impacts on experience; Collaboration - enhancing partnership, enriching knowledge, and mapping the journey's direction; and Connectedness - combating isolation while enhancing unity. Since the key transmission of culture is through language, raw reflections were sought initially in the practitioners' own language, which were translated for an English-speaking readership. These narratives are honest and rich descriptions of the authors' lived experiences, diverse and distinctive. The contributors trust colleagues will find these reflections helpful, validating and acknowledging the challenges of this unique period in history.

13.
Environ Res ; 177: 108623, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31419717

RESUMO

Ribeirão Preto City is supplied by the Guarani Aquifer System and suffers with intense environmental degradation due to growth of the vehicle fleet, burning of cane fields and also with water contamination by agricultural products, such as pesticides and fertilizers. The aim of the present study was to assess the human health risk derived from the exposure to metals through water and air (PM10) for two population groups (adults and children) of the municipality of Ribeirão Preto during the dry and wet seasons. Seasonal and spatial assessments of the metal concentrations in supply wells and household waters and the concentrations of PM10 and its metals were also performed. Element concentrations were determined by inductively coupled plasma spectrometry. Environmental exposure to metals were assessed under a residential scenario and estimated considering the three main routes of exposure: ingestion, dermal contact and inhalation. The results showed a higher concentration of PM10 during the dry season, which may be due to the lower precipitation and higher number of burns in this period. Copper in household waters presented a great increase when compared with the concentrations of the supply wells, probably related to the contamination during the route from its source until the residences supply. Although presenting levels in accordance with the national legislation, household waters in the municipality of Ribeirão Preto may be a concern for human exposure to metals for children during the wet season as well as the levels found for the carcinogenic risk (ELCR).


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Metais/análise , Adulto , Poluentes Atmosféricos , Brasil , Criança , Saúde da Criança , Cidades , Monitoramento Ambiental , Humanos , Metais Pesados , Material Particulado , Medição de Risco
14.
Arch Environ Contam Toxicol ; 75(2): 199-212, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29305811

RESUMO

Located in the southeast of Brazil, the Pardo River Basin has a large population and an economy focused on agriculture, with a strong predominance of the sugarcane agro-industry. The purpose of the study was to assess the water quality of the Pardo River Basin under a multivariate approach using limnological parameters, metal concentrations, and indicator bacteria. Nine sampling campaigns were performed during both the dry and rainy seasons. Element concentrations were determined by inductively coupled plasma spectrometry (ICP-MS, Perkin Elmer Elan 6000). A battery of test to determine limnological parameters was performed (in situ). Total coliforms and Escherichia coli were detected and quantified using Defined Substrate Technology Colilert® and multiple tube dilutions. Principal component analysis and hierarchical cluster analysis were used as multivariate exploratory analysis. In general, the results suggest the influence of rain, possible sewage discharges into the watercourse, and the input of organic matter in some sampling points in both seasons, besides the absence of riparian vegetation in much of the Pardo River. The likely influence of industrial activities that do not have great prominence in the region was supported by temporal/spatial assessment of Cr and V. The water quality monitoring of Pardo River is an important tool for environmental management, and its continuity is indicated to obtain a consistent series of systematic data and thereby support concretely the actions of planning and controlling the use of water from the Pardo River and soil around them.


Assuntos
Metais/análise , Rios/química , Rios/microbiologia , Poluentes Químicos da Água/análise , Qualidade da Água , Agricultura , Bactérias/isolamento & purificação , Brasil , Enterobacteriaceae/isolamento & purificação , Monitoramento Ambiental/métodos , Escherichia coli/isolamento & purificação , Análise Multivariada , Estações do Ano , Esgotos , Microbiologia da Água
16.
J Dairy Res ; 84(4): 479-483, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28929978

RESUMO

We studied the role played by temperature and rennet concentration in the coagulation process for cheese manufacture and the evaluation of their kinetics. We concluded that temperature is the main factor that determines the kinetics. The rennet concentration was unimportant probably due to the fast action of the enzyme chymosin. The Dynamic light scattering technique allowed measuring the aggregate's size and their formation kinetics. The volume fraction of solids was determined from viscosity measurements, showing profiles that are in agreement with the size profiles. The results indicate that the formation of the aggregates for rennet cheese is strongly dependent on temperature and rennet concentration. The results revealed that at 35·5 °C the volume fraction of solids has the maximum slope, indicating that at this temperature the curd is formed rapidly. The optimal temperature throughout the process was established. Second-order kinetics were obtained for the process. We observed a quadratic dependence between the rennet volume and the volume fraction of solids (curd), thereby indicating that the kinetics of the curd production should be of order two.


Assuntos
Queijo , Manipulação de Alimentos/métodos , Quimosina/análise , Quimosina/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Luz , Tamanho da Partícula , Espalhamento de Radiação , Temperatura , Viscosidade
17.
J Dairy Res ; 84(1): 102-108, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27821208

RESUMO

Probiotic-based starter cultures are generally used to produce fermented milks with improved characteristics in the final product. In this study, Lactobacillus casei and Streptococcus thermophilus (Lc1-St) were used as the starter inoculum. The transformation kinetics and properties of the final product were compared with systems produced with other inocula. The Lc1-St inoculum delayed the production of lactic acid from 40 to 70 min (depending on temperature and concentration) when compared to Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus (Lb-St) and Lactobacillus johnsonii and Streptococcus thermophilus (La1-St). The Lc1-St inoculum reached the aggregation system faster (30-80 min) than Lb-St (120-210 min) and La1-St (160-220 min), however, the production of exopolysaccharides and organic phosphates was delayed as a consequence of the lack of synergy between Lc1 and St.


Assuntos
Fermentação , Lacticaseibacillus casei/metabolismo , Leite/microbiologia , Probióticos , Streptococcus thermophilus/metabolismo , Animais , Manipulação de Alimentos/métodos , Cinética , Ácido Láctico/biossíntese , Lactobacillus delbrueckii/metabolismo , Lactobacillus johnsonii/metabolismo , Organofosfatos/metabolismo , Polissacarídeos Bacterianos/biossíntese , Iogurte/microbiologia
18.
Environ Monit Assess ; 187(2): 39, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25632896

RESUMO

This study aimed to verify the capacity of Tradescantia pallida in the biomonitoring of air pollution in urban areas with different traffic intensities and under varying environmental conditions. Experiments were carried out in Ribeirão Preto, in the Southeastern Brazil, with more than 660,000 inhabitants and a fleet of more than 485,000 motor vehicles. Ten seedlings of T. pallida were exposed in three areas in the city, differing in traffic vehicle flow, in two seasons (wet and dry). At the end of each sampling period, which lasted 4 months, samples of leaves were collected, and the content of As, Ba, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Mn, P, Pb, S, and Zn was determined by inductively coupled plasma mass spectroscopy (ICP-MS). The same elements were determined in soil samples for a seasonal characterization in conjunction with secondary data of environmental parameters. Additionally, micronucleus assay with early pollen tetrad cells of Tradescantia (Trad-MN) was conducted by collecting flower buds and analyzing the micronuclei frequencies in pollen mother cells. Although pollutant levels in air were below the Brazilian legal limits, plants exposed in the high-traffic flow area presented higher concentrations of elements related to vehicle emissions, especially under dry conditions, and higher micronuclei frequency in pollen mother cells. These results show the sensitivity of T. pallida to low-level urban air pollution and its suitability as bioindicator for trace elements. This alternative tool for biomonitoring can serve as a support methodology for the adoption of more restrictive public environmental policies in Brazil and extendible to other developing countries.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Tradescantia/química , Poluição do Ar/estatística & dados numéricos , Brasil , Testes para Micronúcleos , Veículos Automotores , Pólen , Estações do Ano , Emissões de Veículos
19.
Environ Monit Assess ; 187(9): 569, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26266898

RESUMO

There is a growing need for strategic assessment of environmental conditions in river basins around the world. In spite of the considerable water resources, Brazil has been suffering from water quality decrease in recent years. Pardo River runs through Minas Gerais and São Paulo, two of the most economically important states in Brazil, and is being currently promoted as a future drinking water source. This study aimed at integrating three different tools to conduct a hydromorphological assessment focused on the spatial complexity, connectivity, and dynamism of the Pardo River, Brazil. Twelve sampling stretches were evaluated in four sampling campaigns, in dry and rainy seasons. In each stretch, permanent preservation areas (PPAs), hydromorphological integrity by rapid assessment protocol (RAP), and physicochemical parameters were qualified. The kappa coefficient was used to assess statistical agreement among monitoring tools. The PPA analysis showed that in all stretches, the vegetation was modified. RAP results revealed environmental deterioration in stretches located near human activities and less variability of substrates available for aquatic fauna and sediment deposition as well. Low values for dissolved oxygen in the river mouth were noted in the rainy season. Electrical conductivity was higher in stretches near sugarcane crops. The poor agreement (k<0.35) between the RAP and physicochemical parameters indicates that the tools generate different and complementary information, while they are not replaceable. Potential changes of the hydromorphological characteristics and variations in physicochemical indicators must be related to extensive PPA modification.


Assuntos
Água Potável/normas , Monitoramento Ambiental/métodos , Rios/química , Qualidade da Água , Agricultura , Brasil , Monitoramento Ambiental/estatística & dados numéricos , Humanos , Estações do Ano , Urbanização , Movimentos da Água
20.
Environ Res ; 133: 149-55, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24949813

RESUMO

Pardo River (Brazil) is suffering from an important anthropogenic impact due to the pressure of highly populated areas and the influence of sugarcane cultivation. The objective of the present study was to determine the levels of 13 trace elements (As, Be, Cd, Cr, Cu, Pb, Mn, Hg, Ni, Tl, Sn, V and Zn) in samples of surface water and sediments from the Pardo River. Furthermore, the human health risks associated with exposure to those metals through oral intake and dermal absorption were also evaluated. Spatial and seasonal trends of the data were closely analyzed from a probabilistic approach. Manganese showed the highest mean concentrations in both water and sediments, remarking the incidence of the agricultural activity and the geological characteristics within the basin. Thallium and arsenic were identified as two priority pollutants, being the most important contributors to the Hazard Index (HI). Since non-carcinogenic risks due to thallium exposure slightly exceeded international guidelines (HI>1), a special effort should be made on this trace element. However, the current concentrations of arsenic, a carcinogenic element, were in accordance to acceptable lifetime risks. Nowadays, there is a clear increasing growth in human population and economic activities in the Pardo River, whose waters have become a serious strategic alternative for the potential supply of drinking water. Therefore, environmental monitoring studies are required not only to assure that the current state of pollution of Pardo River does not mean a risk for the riverside population, but also to assess the potential trends in the environmental levels of those elements.


Assuntos
Exposição Ambiental , Sedimentos Geológicos/química , Metais/análise , Rios/química , Poluentes Químicos da Água/análise , Adulto , Arsênio/efeitos adversos , Brasil , Criança , Água Potável/efeitos adversos , Exposição Ambiental/efeitos adversos , Humanos , Manganês/efeitos adversos , Medição de Risco , Estações do Ano , Tálio/efeitos adversos , Poluentes Químicos da Água/efeitos adversos
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