RESUMO
A new virus, named Mutum virus, related to members of the family Tymoviridae, was isolated from mosquitoes (Mansonia spp.) in clone C6/36 cells, and its complete genome was sequenced. Its genome is 6494 nt in size with an organization resembling that of tymovirids. The isolated virus is phylogenetically related to two viruses isolated from Culex spp. mosquitoes: Ek Balam virus, reported in Mexico, and Culex-originated Tymoviridae-like virus, isolated in China. The results of this study suggest that this virus is a new member of the family Tymoviridae.
Assuntos
Culex , Culicidae , Malvaceae , Tymoviridae , Animais , Brasil , Genoma Viral , Filogenia , Tymoviridae/genéticaRESUMO
AIMS: The purpose of the work was to investigate bacterial levels and diversity as well as survival of Salmonella in used dish washing sponges and brushes and identify consumer practices that can potentially explain bacterial status of these items. METHODS AND RESULTS: Used washing up utensils were collected from consumers. The bacterial numbers (TVC) were very variable with an extremely high median level (10.3 log cfu/item) in Portuguese sponges and lower levels in Norwegian items (7.3 and 7.0 cfu/item for sponges and brushes). No self-reported practices or household composition could explain differences found in TVC levels among the collected sponges. Lower mean TVC levels were found in unworn brushes and brushes regularly cleaned with soap, but the differences were modest (1.5 log or less). A common set of bacteria was found in brushes and sponges, dominated by Acinetobacter, Chryseobacterium, Enhydrobacter, Enterobacteriaceae and Pseudomonas. There was no difference in TVC or bacterial diversity between conventional and antimicrobial sponges containing silver after 4 weeks of use. For used brushes inoculated with Salmonella and allowed to dry overnight, a significant reduction in Salmonella numbers was observed. No reduction was observed for brushes stored in humid conditions (in a plastic bag) or for sponges regardless of storing conditions. CONCLUSIONS: Overall, lower bacterial levels were observed in used brushes than in sponges, and Salmonella died more rapidly in brushes. A common set of non-pathogenic bacteria dominated in brushes and sponges. SIGNIFICANCE AND IMPACT OF STUDY: The study demonstrates that the use of brushes may be more hygienic than the use of sponges.
Assuntos
Bactérias , Salmonella , Enterobacteriaceae , HigieneRESUMO
Epidemiological studies show that improper food handling practices at home account for a significant portion of foodborne illness cases. Mishandling of raw meat during meal preparation is one of the most frequent hazardous behaviours reported in observational research studies that potentially contributes to illness occurrence, particularly through the transfer of microbial pathogens from the raw meat to ready-to-eat (RTE) foods. This study evaluated the transfer of two major foodborne pathogens, Salmonella enterica and Listeria monocytogenes, from artificially contaminated chicken meat to lettuce via cooking salt (used for seasoning) during simulated domestic handling practices. Pieces of chicken breast fillets were spiked with five different loads (from ca. 1 to 5 Log CFU/g) of a multi-strain cocktail of either S. enterica or L. monocytogenes. Hands of volunteers (gloved) contaminated by handling the chicken, stirred the cooking salt that was further used to season lettuce leaves. A total of 15 events of cross-contamination (three volunteers and five bacterial loads) were tested for each pathogen. Immediately after the events, S. enterica was isolated from all the cooking salt samples (n = 15) and from 12 samples of seasoned lettuce; whereas L. monocytogenes was isolated from 13 salt samples and from all the seasoned lettuce samples (n = 15). In addition, S. enterica and L. monocytogenes were able to survive in artificially contaminated salt (with a water activity of 0.49) for, at least, 146 days and 126 days, respectively. The ability of these foodborne pathogens to survive for a long time in cooking salt, make it a good vehicle for transmission and cross-contamination if consumers do not adopt good hygiene practices when preparing meals.
RESUMO
Drug abuse has become a public health concern. The misuse of ketamine, a psychedelic substance, has increased worldwide. In addition, the co-abuse with alcohol is frequently identified among misusers. Considering that ketamine and alcohol share several pharmacological targets, we hypothesize that the consumption of both psychoactive substances may synergically intensify the toxicological consequences, both under the effect of drugs available in body systems and during withdrawal. The aim of this review is to examine the toxicological mechanisms related to ketamine plus ethanol co-abuse, as well the consequences on cardiorespiratory, digestive, urinary, and central nervous systems. Furthermore, we provide a comprehensive discussion about the probable sites of shared molecular mechanisms that may elicit additional hazardous effects. Finally, we highlight the gaps of knowledge in this area, which deserves further research.
Assuntos
Ketamina , Transtornos Relacionados ao Uso de Substâncias , Etanol , Humanos , Ketamina/efeitos adversosRESUMO
Nontyphoidal salmonellae are among the most prevalent foodborne pathogens causing gastrointestinal infections worldwide. A high number of cases and outbreaks of salmonellosis are associated with the consumption of eggs and egg products, and several of these occur at the household level. The aim of the current study is to critically evaluate the current status of knowledge on Salmonella in eggs from a consumer's perspective, analyzing the hazard occurrence and the good practices that should be applied to reduce salmonellosis risk. Following a HACCP (Hazard Analysis and Critical Control Point) based approach, some steps along the food journey were identified as Critical Consumer Handling (CCH)-steps in which consumers, through their behavior or choice, can significantly reduce the level of Salmonella in eggs and egg products. From shopping/collecting to consumption, each of these steps is discussed in this review to provide an evidence-based overview of risk factors of human salmonellosis related to egg consumption. The main message to consumers is to choose Salmonella-free eggs (those that some official entity or producer guarantees that does not contain Salmonella), when available, especially for dishes that are not fully heat treated. Second, as guaranteed Salmonella-free eggs are only available in a few countries, refrigerated storage from the point of collection and proper cooking will significantly reduce the risk of salmonellosis. This will require a revision of the actual recommendations/regulations, as not all ensure that eggs are maintained at temperatures that prevent growth of Salmonella from collection until the time of purchasing.
Assuntos
Intoxicação Alimentar por Salmonella , Infecções por Salmonella , Ovos , Humanos , Fatores de Risco , Salmonella , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologiaRESUMO
BACKGROUND: Sarcopenia is a geriatric syndrome associated with negative health outcomes and the use of viable alternative screening tools may help in the diagnosis of this condition. This study aimed to analyze the association of sarcopenia with anthropometric indicators among community-dwelling older adults and to identify cut-off points for such indicators as a discriminant criterion for predicting sarcopenia. METHODS: This was a cross-sectional study conducted on community-dwelling older adults ≥60 years old (n = 411) of both sexes from Macapá, Amapá, Brazil. Socioeconomic, clinical and anthropometric data (arm circumference - AC, waist circumference - WC, calf circumference - CC and body mass index - BMI) were collected using a structured form. Sarcopenia was identified according to the EWGSOP 2 consensus. The association between anthropometric indicators and sarcopenia was performed using logistic regression and cut-off points established from the ROC Curve. Statistical significance was defined as p ≤ 0.05. RESULTS: Adjusted analysis indicated an independent and inverse association between sarcopenia and the anthropometric indicators: AC (odds ratio, OR: 0.63; 95% confidence interval, 95%CI: 0.53-0.76), CC (OR: 0.73; 95%CI: 0.62-0.85), WC (OR: 0.93; 95%CI: 0.90-0.97) and BMI (OR: 0.64; 95%CI: 0.53-0.76). The following cut-off points for older men and women represented the discriminant criterion for the presence of sarcopenia: WC (≤97 and ≤ 86 cm), CC (≤33 and ≤ 31 cm), AC (≤27 cm) and BMI (≤24.8 kg/m2 and ≤ 24.5 kg/m2) (area under the ROC curve superior to 0.70). BMI and AC were the indicators with the highest ability to discriminate older adults of both sexes with sarcopenia. CONCLUSIONS: An increase of one unit of the indicators can reduce the probability of occurrence of sarcopenia. All indicators were considered to discriminate the occurrence of sarcopenia, with emphasis on BMI and AC, and could be used to screen for this condition among community-dwelling older adults.
Assuntos
Sarcopenia , Idoso , Antropometria , Índice de Massa Corporal , Brasil/epidemiologia , Estudos Transversais , Feminino , Força da Mão , Humanos , Vida Independente , Masculino , Curva ROC , Sarcopenia/diagnóstico , Sarcopenia/epidemiologiaRESUMO
The objective of this work was to investigate the effect of stress conditions frequently encountered in food-associated environments on virulence-associated characteristics of eight strains of Listeria monocytogenes. Strains were grown at low (11⯰C, cold stress) and optimal (37⯰C) temperatures and in high NaCl concentrations (6% NaCl, 11⯰C; cold-osmotic stress) and tested for their ability to invade the human intestinal epithelial Caco-2â¯cells. Results demonstrate that the correlation between exposure to cold stress and increased invasion phenotype is strain-dependent as strains investigated exhibited different behaviours, i.e. exposure to cold stress conditions resulted in a significant increase of invasion levels in five out of the eight strains tested, when compared to growth under optimal conditions. On the other hand, when these cold-adapted cells were subsequently submitted to high salt concentrations and low temperature, their enhanced ability to invade Caco-2 was lost. Surprisingly, saturated fatty acids (SFA) and branched chain fatty acids (BCFA) decreased when L. monocytogenes were exposed to stress conditions as opposed to what has been observed in other studies, therefore highlighting that further studies will need to deepen in the understanding of the lipid metabolism of these strains. The effect of stress conditions on the survival of three selected L. monocytogenes strains through an in vitro gastrointestinal (GI) tract digestion model was further investigated. The exposure to cold-osmotic stress increased the survival of one strain through the GI tract.
Assuntos
Listeria monocytogenes/fisiologia , Listeriose/microbiologia , Adaptação Fisiológica , Células CACO-2 , Temperatura Baixa , Contagem de Colônia Microbiana , Humanos , Listeria monocytogenes/química , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/patogenicidade , Pressão Osmótica , Cloreto de Sódio/metabolismo , Estresse Fisiológico , VirulênciaRESUMO
Non-thermal food processing and replacement of chemical additives by natural antimicrobials are promising trends in the food industry. The objective of the present work was to evaluate the effect of a process which combines mild high hydrostatic pressure - HHP (200 and 300â¯MPa, 5â¯min, 10⯰C), phage Listex™ P100 and the bacteriocin pediocin PA-1 as a new non-thermal process for destruction of Listeria monocytogenes (104â¯CFUâ¯mL-1 or 107â¯CFUâ¯mL-1) in milk. For inoculum levels of 104â¯CFUâ¯mL-1, HHP combined with phage P100 eliminated L. monocytogenes immediately after pressurization. When L. monocytogenes was inoculated at levels of 107â¯CFUâ¯mL-1, a synergistic effect between phage P100, pediocin PA-1 and HHP (300â¯MPa) on the inactivation of L. monocytogenes was observed during storage of milk at 4⯰C. For non-pressure treated samples inoculated with phage or pediocin or both, L. monocytogenes counts decreased immediately after biocontrol application, but regrowth was observed in a few samples during storage. Phage particles were stable during refrigerated storage for seven days while pediocin PA-1 remained stable only during three days. Further studies will have to be performed to validate the findings of this work in specific applications (e.g. production of raw milk cheese).
Assuntos
Bacteriófagos/fisiologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/virologia , Leite/microbiologia , Pediocinas/farmacologia , Animais , Bovinos , Contagem de Colônia Microbiana , Conservação de Alimentos/instrumentação , Pressão Hidrostática , Listeria monocytogenes/química , Listeria monocytogenes/crescimento & desenvolvimentoRESUMO
The application of lytic phages as biocontrol agents is emerging as a promising strategy towards elimination or reduction of foodborne pathogens in a variety of food products. This technology is particularly advantageous for minimally processed and ready-to-eat (RTE) foods. In this study, the potential use of Listex™ P100 combined with high hydrostatic pressure (HPP), to enhance the control of Listeria monocytogenes in food was evaluated. For that, the effect of three pressures (200, 300 or 400â¯MPa; 5â¯min, 10⯰C) on phage P100 stability was tested when inoculated in six different matrices: phosphate buffered saline (PBS, pH 7.4); apple juice (pH 3.41); orange/carrot nectar (pH 3.54); UHT whole milk (pH 6.73); and, two traditional Portuguese fermented products, "Serra da Estrela" cheese (pH 5.66) and "Alheira", a meat sausage (pH 6.07). The results showed that treatment at 400â¯MPa reduced phage titres to below the detection level in all matrices, whereas at milder pressures the survival of the phage was matrix dependent. "Alheira", "Serra da Estrela" cheese and UHT whole milk were shown to be baroprotective matrices that support phage P100 application in HHP up to 300â¯MPa; however, an accentuated phage inactivation was observed in apple and orange/carrot nectar, which may be related to the acidic pH values of these matrices. The initial phage load did not affect the inactivation rate during HHP processing (300â¯MPa, 5â¯min, 10⯰C) in PBS, cheese, sausage or milk matrices, and the phage titres were stable in these matrices during storage at 4⯰C for 28 days for milk and 60 days for "Alheira" and "Serra da Estrela" cheese. In addition, a baroprotective effect on phage stability was observed when PBS was supplemented with reducing sugars, dextrin, casein, and tween 80. In conclusion, at mild HHP treatment, phage P100 remained active in specific matrices and seems to present potential to be added in non-thermal inactivation of L. monocytogenes.
Assuntos
Bacteriófagos/fisiologia , Queijo/microbiologia , Fast Foods/microbiologia , Conservação de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Listeria monocytogenes/virologia , Produtos da Carne/microbiologia , Leite/microbiologia , Animais , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/instrumentação , Pressão Hidrostática , Listeria monocytogenes/fisiologiaRESUMO
The effect of high hydrostatic pressure (HHP) on the survival of 14 strains of Listeria monocytogenes from food or clinical origins, selected to represent different pheno and genotypes, was evaluated. Stationary phase cells were submitted to 300, 400 and 500 MPa at 10 °C, for 5 min. A high variability in the resistance of L. monocytogenes to pressure was observed, and particularly two strains isolated from food were significantly more baroresistant than the rest. Strains of L. monocytogenes resistant to one or more antibiotics exhibited significantly higher levels of survival after the high pressure treatment at 400 MPa. No correlation was found between strains' origin or thermal tolerance and resistance to HHP. The suitability of two strains of L. innocua as surrogates of L. monocytogenes, was also investigated. These exhibited significantly higher sensitivities to HHP than observed for some L. monocytogenes. The antimicrobial effect of the antilisterial bacteriocin (bacHA-6111-2) increased after L. monocytogenes cells had been exposed to pressure. The data obtained underlines the importance of strain selection for studies aiming to evaluate HHP efficacy to ensure safety of HHP-treated foods.
Assuntos
Pressão Hidrostática , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/fisiologia , Viabilidade Microbiana , Pediocinas/farmacologia , Contagem de Colônia Microbiana , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Inocuidade dos Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/microbiologia , TermotolerânciaRESUMO
Listeria monocytogenes is a food-borne pathogen responsible for outbreaks and sporadic cases of listeriosis, a severe invasive disease. Internalin A (InlA) a protein encoded by inlA has a key role in the mechanism of pathogenesis in L. monocytogenes infection, specifically in the invasion of human intestinal epithelial cells. Studies on inlA have shown that mutations leading to premature stop codons (PMSCs) occur naturally and are associated with impaired virulence of L. monocytogenes strains. Increasing evidence suggests that inlA PMSCs mutations are frequent in strains from foods, but rare among clinical isolates. In this study, 22 L. monocytogenes strains collected in Portugal from the processing environment of a bakery industry (n = 1), different food products (n = 10) and human clinical cases (n = 11) were analysed for mutations in inlA and invasion efficiency in Caco-2 cells. Sequencing revealed previously reported mutations types leading to PMSCs in three food and one clinical strain presenting different molecular serotypes (i.e., IIa, IIb and IIc). The remaining 18 isolates did not show PMSCs in inlA. The four strains with PMSCs in inlA presented lower invasiveness efficiencies in Caco-2 cells (below 8.9%) when compared to the control strain (full-length InlA). In addition, one clinical isolate showed reduced invasion efficiency but no PMSCs in inlA. This isolate showed increased inlA transcript levels to that obtained for the laboratory control strain. Our data support the hypothesis that L. monocytogenes isolated from food have attenuated invasion due to the presence of inlA PMSCs. This information would be critically needed for adequate risk-assessments of the foodborne illness burden associated with L. monocytogenes strains.
Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Códon sem Sentido , Microbiologia de Alimentos , Listeria monocytogenes/genética , Células CACO-2 , Células Epiteliais , Genótipo , Humanos , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Mutação , Fenótipo , Portugal , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNARESUMO
OBJECTIVE: The purpose of this study was to correlate upper limb volume and arterial and venous blood flow velocity in breast cancer survivors. METHODS: A cross-sectional study was conducted on 30 women with lymphedema and a mean age of 55.60 years (standard deviation = 8.12). For the assessment of upper limb volume, perimetry was performed with measures at 6 points on the limb, which were mathematically calculated as volume. The blood flow velocity of the axillary and brachial arteries and veins were assessed by Doppler ultrasound with a probe at 4 MHz. In the statistical analysis, a Shapiro-Wilk test determined a non-normal data distribution. Spearman correlation coefficients (ρ) were calculated to determine the association between the variables blood flow velocity and lymphedema volume. RESULTS: We identified significant and positive associations between all variables correlated with limb volume: blood flow velocity of the axillary artery (ρ = 0.381, P = .041), axillary vein (ρ = 0.383, P = .039), brachial artery (ρ = 0.375, P = .044), and the brachial vein (ρ = 0.373, P = .045). CONCLUSION: There is a positive association between limb volume and blood flow velocity in the upper limbs of women with lymphedema secondary to breast cancer treatment.
Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Linfedema/diagnóstico por imagem , Mastectomia/efeitos adversos , Ultrassonografia Doppler/métodos , Adulto , Idoso , Artéria Axilar/diagnóstico por imagem , Artéria Braquial/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Estudos Transversais , Feminino , Humanos , Linfedema/etiologia , Linfedema/fisiopatologia , Mastectomia/métodos , Pessoa de Meia-Idade , Valores de Referência , Índice de Gravidade de DoençaRESUMO
Relatively little is known about the role of foods in the chain of transmission of acinetobacters and the occurrence of different Acinetobacter spp. in foods. Currently, there is no standard procedure to recover acinetobacters from food in order to gain insight into the food-related ecology and epidemiology of acinetobacters. This study aimed to assess whether enrichment in Dijkshoorn enrichment medium followed by plating in CHROMagar™ Acinetobacter medium is a useful method for the isolation of Acinetobacter spp. from foods. Recovery of six Acinetobacter species from food spiked with these organisms was compared for two selective enrichment media (Baumann's enrichment and Dijkshoorn's enrichment). Significantly (p < 0.01) higher cell counts were obtained in Dijkshoorn's enrichment. Next, the Dijkshoorn's enrichment followed by direct plating on CHROMagar™ Acinetobacter was applied to detect Acinetobacter spp. in different foods. Fourteen different presumptive acinetobacters were recovered and assumed to represent nine different strains on the basis of REP-PCR typing. Eight of these strains were identified by rpoB gene analysis as belonging to the species Acinetobacter johnsonii, Acinetobacter calcoaceticus, Acinetobacter guillouiae and Acinetobacter gandensis. It was not possible to identify the species level of one strain which may suggests that it represents a distinct species.
Assuntos
Acinetobacter/enzimologia , Acinetobacter/crescimento & desenvolvimento , Acinetobacter/isolamento & purificação , Microbiologia de Alimentos/métodos , Verduras/microbiologia , Acinetobacter/genética , Técnicas de Tipagem Bacteriana , Meios de Cultura/metabolismo , Microbiologia de Alimentos/instrumentaçãoRESUMO
A survey in 16 activated sludge wastewater treatment plants (WWTP) was conducted to contribute to the knowledge of the environmental parameters that determine the composition of the filamentous community. A total of 128 samples of mixed liquor from municipal WWTP were collected during 2 years, and 22 filamentous morphotypes were identified. The most frequent and abundant filamentous bacteria were, in both cases and by this order, type 0041/0675, type 0092, Microthrix parvicella and 1851, nocardioforms and Haliscomenobacter hydrossis. Concerning dominance, type 1851 was the most frequently dominant morphotype, followed by M. parvicella and types 0092 and 0041/0675. These were also, and by this order, the dominant morphotypes during bulking occurrences. Significant correlations were obtained between the abundance of filamentous bacteria and environmental parameters, but multivariate statistical analysis only confirmed the correlation between type 0092 and Sludge Volume Index (SVI), emphasizing the association of this filament with bulking. The discussion of the results in light of published works was complicated by the random use of terms such as frequency, abundance, and dominance with different and often unclear meanings. This reinforces the need of clarifying these terms when discussing the causes of filamentous overgrowth in WWTP.
Assuntos
Bactérias/isolamento & purificação , Esgotos/microbiologia , Bactérias/classificação , Bactérias/genética , Ecossistema , Portugal , Esgotos/análise , Águas Residuárias/análise , Águas Residuárias/microbiologia , Purificação da Água/instrumentação , Purificação da Água/métodosRESUMO
[Purpose] This study attempted to assess the impact of pain on the life of breast cancer survivors using the Brief Pain Inventory (BPI). [Subjects and Methods] A cross-sectional study was conducted. Participants comprised 30 women, aged 30-80â years, who had received treatment for breast cancer (surgery and complementary treatment) at least 12 months prior to the study and had reported chronic pain related to the treatment procedures. [Results] The highest scores were found for "mood" (median: 5.00 points; first quartile: 1.00 points; third quartile: 7.25 points), "normal work" (median: 5.00 points; first quartile: 0.00 points; third quartile: 8.00 points), and "sleep" (median: 4.50 points, first quartile: 0.00 points, third quartile: 8.00 points). [Conclusion] Pain exerts a negative impact primarily on mood, normal work, and sleep among breast cancer survivors.
RESUMO
Listeria monocytogenes infection (listeriosis) is an uncommon but severe foodborne illness that affects mainly individuals with recognized underlying conditions: the elderly, immunocompromised individuals, and pregnant women and their fetuses. The aim of this study was to obtain epidemiological data on cases of listeriosis occurring in Portugal from 2008 through 2012, collected in hospitals on a voluntary basis. L. monocytogenes isolates were characterized by genoserotyping by multiplex polymerase chain reaction, DNA macrorestriction pulsed-field gel electrophoresis (PFGE), and determination of minimal inhibitory concentration (MIC, µg/mL) for 12 antibiotics. During this period, 203 cases of listeriosis were detected. The annual incidence rate observed ranged from 0.2 to 0.7 cases per 100,000 inhabitants. Nineteen cases (9.5%) corresponded to maternal/neonatal (MN) infections. The mean age of the nonmaternal/neonatal (non-MN) cases with documented age was 59 years, and 46.4% occurred in patients aged over 65 years. The majority of listeriosis cases were caused by genoserogroup IVb isolates, and PFGE analysis revealed a high molecular diversity, suggesting that most were sporadic. Nevertheless, several clusters of isolates presenting different geographic and time distributions were detected. The incidence of antibiotic-resistant isolates of L. monocytogenes was low but significantly higher than in previous years (2003-2007). The implementation of a national surveillance system monitoring the incidence of listeriosis and antimicrobial resistance of strains would be most valuable, allowing identification of sporadic and outbreak cases, to detect general trends in antibiotic susceptibilities, and potentially identify food sources of clinical strains.
Assuntos
Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Listeriose/epidemiologia , Listeriose/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Listeria monocytogenes/classificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Portugal , Gravidez , SorotipagemRESUMO
An urban wastewater treatment plant (WWTP) with two different parallel lines of treatment and located in the north of Portugal was studied during four months, following recurrent episodes of filamentous bulking caused by Sphaerotilus natans and eventual occurrences of Nocardioforms and Type 1863. An aerobic selector was introduced in both lines in the beginning of the studied period, suppressed in one of the lines during six weeks, and then put into operation again until the end of the study. A total of 14 filamentous bacteria morphotypes were identified. The results showed that the presence of an aerobic biological selector in continuous operation prevented the overgrowth of the filamentous Type 1863, of Nocardioforms and, in particular, of S. natans. Simultaneously, it allowed lowering the oxygen levels in the aeration tanks without negative consequences in the overall performance of the WWTP, namely bulking occurrence. Dissolved oxygen (DO) in the aeration tank varied initially between 2 and 3 mg/L, but the introduction of the selector enabled to lower it to 1-1.5 mg/L in the aeration tank and around 0.5 mg/L in the selector. A significant energy save was allowed, even considering the aeration of the selector. The results are more relevant if one considers the fact that the main cause of the bulking problems in this WWTP was the overgrowth of S. natans, a filamentous bacterium known to be stimulated by low DO levels.
Assuntos
Sphaerotilus/fisiologia , Gerenciamento de Resíduos , Águas Residuárias/microbiologia , AerobioseRESUMO
The aim of this study was to characterize a broad collection of isolates of Listeria monocytogenes, of different serotypes, recovered in Portugal between 2003 and 2007 from foods (n=353) and from clinical cases of human listeriosis (n=95), in terms of antimicrobial susceptibility. All the isolates were susceptible to ampicillin, the preferred agent to treat listeriosis. Resistances to nitrofurantoin (n=99), to ciprofloxacin (n=18), to erythromycin (n=10), to tetracycline (n=2), to gentamicin (n=1) and to rifampicin (n=1) were observed. One hundred (28.3%) and 20 (21.0%) food and clinical isolates, respectively, were resistant to at least one antibiotic. Eight isolates (1.8%) were resistant to two or more antimicrobials of different classes, and all were collected from foods. Serogroup IVb included the highest percentage of isolates resistant to erythromycin. The highest percentages of isolates resistant to nitrofurantoin were of serogroup IVb and IIc. It was demonstrated that the incidence of antibiotic-resistant isolates of L. monocytogenes, during the period 2003 to 2007, was low in Portugal but still higher than that observed in other countries. Given the increasing population at greater risk of listeriosis, namely, the elderly, the high mortality rate of the infection and the detection of resistant isolates, monitoring for antibiotic resistance in strains of L. monocytogenes on a large scale, and assessing the risk of infection by these strains, is highly recommended.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Listeriose/epidemiologia , Idoso , Humanos , Listeria monocytogenes/classificação , Listeria monocytogenes/isolamento & purificação , Listeriose/microbiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase Multiplex , Portugal/epidemiologiaRESUMO
BACKGROUND: Mansonia mosquitoes transmit arboviruses to humans. This study describes the karyotypes and C-banding of Mansonia humeralis, Mansonia titillans, Mansonia pseudotitillans, and Mansonia indubitans. METHODS: From the 202 larvae, the brain ganglia were dissected (n=120) for the preparation of slides. Twenty slides with well-distended chromosomes for each species (10 for karyotyping and 10 for C-banding) were selected for further study. RESULTS: The haploid genome and the average lengths of the chromosomal arms differed in relation to the centromere between species, and intraspecific differences also occurred in the distribution of the C-bands. CONCLUSIONS: These results are useful for better understanding of the chromosomal variability of Mansonia mosquitoes.
Assuntos
Culicidae , Humanos , Animais , Culicidae/genética , Heterocromatina/genética , Brasil , Cariótipo , CariotipagemRESUMO
Communication between Deaf and hearing individuals remains a persistent challenge requiring attention to foster inclusivity. Despite notable efforts in the development of digital solutions for sign language recognition (SLR), several issues persist, such as cross-platform interoperability and strategies for tokenizing signs to enable continuous conversations and coherent sentence construction. To address such issues, this paper proposes a non-invasive Portuguese Sign Language (Língua Gestual Portuguesa or LGP) interpretation system-as-a-service, leveraging skeletal posture sequence inference powered by long-short term memory (LSTM) architectures. To address the scarcity of examples during machine learning (ML) model training, dataset augmentation strategies are explored. Additionally, a buffer-based interaction technique is introduced to facilitate LGP terms tokenization. This technique provides real-time feedback to users, allowing them to gauge the time remaining to complete a sign, which aids in the construction of grammatically coherent sentences based on inferred terms/words. To support human-like conditioning rules for interpretation, a large language model (LLM) service is integrated. Experiments reveal that LSTM-based neural networks, trained with 50 LGP terms and subjected to data augmentation, achieved accuracy levels ranging from 80% to 95.6%. Users unanimously reported a high level of intuition when using the buffer-based interaction strategy for terms/words tokenization. Furthermore, tests with an LLM-specifically ChatGPT-demonstrated promising semantic correlation rates in generated sentences, comparable to expected sentences.