Dental Surgical Activity in Hospitals during COVID-19: A Nationwide Observational Cohort Study.

INTRODUCTION: The number of surgical extractions performed in hospitals in England remains unclear. This study reports the volume of surgical extractions conducted in hospitals and change in activity during the COVID-19 pandemic. METHODS: We conducted a nationwide observational cohort study using Hospital Episode Statistics (HES) in England for patients undergoing surgical removal of a tooth (defined using OPSC-4 code F09) between April 1, 2015, and December 31, 2020. Procedures were stratified by age, gender, and urgency (elective or nonelective), reported using descriptive statistics, number, and percentage. We conducted post hoc modeling to predict surgical activity to December 2023. In addition, we contrasted this with aggregate national data on simple dental extraction procedures and drainage of dental abscesses in hospital as well as dental activity in general practice. RESULTS: We identified a total of 569,938 episodes for the surgical removal of a tooth (females 57%). Of these, 493,056/569,938 (87%) were for adults and 76,882/569,938 (13%) children ≤18 years. Surgical extractions were most frequent in adult females. Elective cases accounted for 96% (n = 548,805/569,938) of procedures. The median number of procedures carried out per quarter was 27,256, dropping to 12,003 during the COVID-19 pandemic, representing a 56% reduction in activity. This amounted to around 61,058 cancelled procedures. Modeling predicts that this activity has not returned to prepandemic levels. CONCLUSIONS: The number of surgical extractions taking place in hospitals during the pandemic fell by 56%. The true impact of this reduction is unknown, but delayed treatment increases the risk of complications, including life-threatening infections. KNOWLEDGE TRANSFER STATEMENT: The result of this study provides an evidence-based overview of the trends relating to surgical extractions of teeth in England taking place in hospitals. This information can be used to inform service and workforce planning to meet the needs of patients requiring surgical extractions. The data also provide an insight into the oral health needs of the population in England.

Developing and validating high-value patient digital follow-up services: a pilot study in cardiac surgery.

BACKGROUND: The existing digital healthcare solutions demand a service development approach that assesses needs, experience, and outcomes, to develop high-value digital healthcare services. The objective of this study was to develop a digital transformation of the patients' follow-up service after cardiac surgery, based on a remote patient monitoring service that would respond to the real context challenges. METHODS: The study followed the Design Science Research methodology framework and incorporated concepts from the Lean startup method to start designing a minimal viable product (MVP) from the available resources. The service was implemented in a pilot study with 29 patients in 4 iterative develop-test-learn cycles, with the engagement of developers, researchers, clinical teams, and patients. RESULTS: Patients reported outcomes daily for 30 days after surgery through Internet-of-Things (IoT) devices and a mobile app. The service's evaluation considered experience, feasibility, and effectiveness. It generated high satisfaction and high adherence among users, fewer readmissions, with an average of 7 ± 4.5 clinical actions per patient, primarily due to abnormal systolic blood pressure or wound-related issues. CONCLUSIONS: We propose a 6-step methodology to design and validate a high-value digital health care service based on collaborative learning, real-time development, iterative testing, and value assessment.

Mortality after surgery with SARS-CoV-2 infection in England: a population-wide epidemiological study.

BACKGROUND: The COVID-19 pandemic has heavily impacted elective and emergency surgery around the world. We aimed to confirm the incidence of perioperative severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and associated mortality after surgery. METHODS: Analysis of routine electronic health record data from NHS hospitals in England. We extracted data from Hospital Episode Statistics in England describing adult patients undergoing surgery between January 1, 2020 and February 28, 2021. The exposure was SARS-CoV-2 infection defined by International Classification of Diseases (ICD)-10 codes. The primary outcome measure was 90 day in-hospital mortality. Data were analysed using multivariable logistic regression adjusted for age, sex, Charlson Comorbidity Index, Index of Multiple Deprivation, presence of cancer, surgical procedure type and admission acuity. Results are presented as n (%) and odds ratios (OR) with 95% confidence intervals (CI). RESULTS: We identified 2 666 978 patients undergoing surgery of whom 28 777 (1.1%) had SARS-CoV-2 infection. In total, 26 364 (1.0%) patients died in hospital. SARS-CoV-2 infection was associated with a much greater risk of death (SARS-CoV-2: 6153/28 777 [21.4%] vs no SARS-CoV-2: 20 211/2 638 201 [0.8%]; OR=5.7 [95% CI, 5.5-5.9]; P<0.001). Amongst patients undergoing elective surgery, 2412/1 857 586 (0.1%) had SARS-CoV-2, of whom 172/2412 (7.1%) died, compared with 1414/1 857 586 (0.1%) patients without SARS-CoV-2 (OR=25.8 [95% CI, 21.7-30.9]; P<0.001). Amongst patients undergoing emergency surgery, 22 918/582 292 (3.9%) patients had SARS-CoV-2, of whom 5752/22 918 (25.1%) died, compared with 18 060/559 374 (3.4%) patients without SARS-CoV-2 (OR=5.5 [95% CI, 5.3-5.7]; P<0.001). CONCLUSIONS: The low incidence of SARS-CoV-2 infection in NHS surgical pathways suggests current infection prevention and control policies are highly effective. However, the high mortality amongst patients with SARS-CoV-2 suggests these precautions cannot be safely relaxed.

Plastics in surface water of southern coastal belt of Sri Lanka (Northern Indian Ocean): Distribution and characterization by FTIR.

This study focused on investigating the occurrence, quantification, and the spatial and temporal distribution of plastics in coastal surface water from 12 coastal regions in southern part of Sri Lanka. The overall average densities of macroplastics and mesoplastics were recorded as 0.23 and 0.33 items/m3, respectively. Sampling locations had no significant difference (p > 0.05) on total microplastics (MPs) density (overall mean MPs density: 17.45 ± 3.35 items/m3). MPs debris of less than 1 mm size consisted of >45% of the total number of MPs, whereas the maximum size of microscopically observed plastic debris was 11.04 mm, a filament. Filaments were the most common MPs followed by films. Relatively, blue-colored MPs were highly abundant in this coastal line. The type of MPs was further confirmed by Fourier-Transform Infrared (FTIR) method. Potential plastic pollution factors are hydrodynamics and man-made activities like unsustainable harbor operations, fisheries, and tourism. More attention is needed to reduce plastic pollution regionally.

Consumer perception and sensory profile of probiotic yogurt with added sugar and reduced milk fat.

The objective of this study was to determine the effect of different milk fat (MF, 0%, 1.5%, 3.3% (w/w)) or added sugar (AS, 0%, 3.5%, 7% (w/w)) levels on the sensory properties and consumer acceptability of probiotic set yogurts fermented by Streptococcus thermophilus, Bifidobacterium bifidum, and Lactobacillus delbrueckii subsp. bulgaricus. The experimental yoghurt samples were compared with a control containing AS, 7% and MF, 3.3%. A quantitative descriptive analysis was conducted using 12 semi-trained panelists to evaluate the sensory profile of yogurts by rating the intensity of sensory descriptors on a 10 unit scale. Consumer preferences was determined using a group untrained individuals (n = 31) by applying the hedonic test for preference. Sensory mapping and Principal Component Analysis (PCA) were conducted to obtain a comprehensive understanding of the consumer behavior. Partial Least Squares Regression (PLSR) was conducted to compare the sensory profiling, consumer preference and instrumental data. Descriptive data showed significant differences (p < 0.05) among the samples for 8 of the 15 attributes amalyzed, including flavor and texture parameters. PCA showed that more than 80% of consumers highly preferred the low-fat yogurt, basically due to its firmness. Overall, consumer preference decreases with the AS reduction. The sample containing zero sugar is the least preferred sample. The reduction of added sugar below 3.5% is a challenge in terms of retaining product quality.

Pre-donation deferral of blood donors in a Brazilian blood bank: a 10-year experience.

OBJECTIVES: To study the main causes of pre-donation blood donors' deferral in a Brazilian blood bank. BACKGROUND: Blood donor selection is the most important process to maintain transfusion safeness. Pre-donation deferral aims to avoid the transmission of infectious diseases in the serological window, as well as to preserve blood donors' health. METHODS: This was a retrospective study undertaken in a single blood centre in Curitiba, Brazil, taking into account the number of blood donations per year, the number of annual donations by gender and the total number of blood donors deferred annually prior to blood donation from 1 January 2007 to 31 December 2016. RESULTS: Pre-donation blood donors' deferral ranged from 12·1 to 15·7% of donors. The main reason was related to donors' health (22·5-51·4%) followed by behavioural risk (17·6-29%). Issues related to blood donors' health diminished, and those related to behavioural risk increased with time. Blood donors deferred because of anaemia diminished with time and were more common in women than men (P < 0·001). CONCLUSIONS: Pre-donation blood donors' deferral ranges from 12·1 to 15·7% in our region. The most common cause was blood donors' health followed by behavioural risk. Anaemia was more common in women. Knowing this specific population better could avoid wasting blood bags and help to minimise costs and still maintain transfusion safety.

Ocorrência de Campylobacter e Enterobacteriaceae em aves silvestres e frangos de corte / Campylobacter and Enterobacteriaceae in wild birds and poultry

As aves silvestres podem ser reservatório de bactérias patogênicas e atuar como veiculadoras desses microrganismos para o ambiente, os animais domésticos e o homem. Portanto, o objetivo deste trabalho foi verificar a ocorrência de Campylobacter spp., Yersinia enterocolitica e Salmonella enterica em aves silvestres capturadas nas áreas próximas de aviários e em frangos de corte alojados nesses estabelecimentos, além de verificar a presença dos genes cdtA, cdtB e cdtC nos isolados de Campylobacter e identificar os sorotipos de Salmonella encontrados. Amostras de fezes de 189 aves silvestres capturadas com redes de neblina nas áreas próximas de 10 aviários e de 200 frangos de corte foram processadas para pesquisa de Campylobacter spp., S. enterica e Y. enterocolitica. Duas espécies de aves silvestres, Sicalis flaveola (canário-da-terra) e Zonotrichia capensis (tico-tico), foram positivas para Salmonella e Campylobacter, respectivamente. Foram isolados Campylobacter spp., S. enterica e Y. enterocolitica de frangos. Todos os isolados de Campylobacter analisados apresentaram os genes cdt. Em dois aviários, Campylobacter foi isolado tanto de frangos como de aves silvestres, entretanto a contaminação mútua entre essas aves não foi comprovada. Este foi o primeiro relato de isolamento de Campylobacter de Z. capensis e de Salmonella do sorotipo Derby de S. flaveola.(AU)

Wild birds can be reservoirs of pathogenic bacteria and act as carriers of these microorganisms to the environment, domestic animals, and humans. Therefore, this study had as objective to verify the occurrence of Campylobacter spp., Yersinia enterocolitica and Salmonella enterica in wild birds captured in the surroundings of the aviaries and in the broilers housed in these establishments. The presence of the cdtA, cdtB and cdtC genes in Campylobacter isolates was also investigated and Salmonella serotypes were identified. Stool samples from 189 wild birds captured with mist nets in around 10 aviaries and from 200 broilers were processed for Campylobacter spp., S. enterica and Y. enterocolitica research. Two species of wild birds, Sicalis flaveola (Saffron Finch) and Zonotrichia capensis (Rufous-collared Sparrow) were positive for Salmonella and Campylobacter, respectively. Campylobacter spp., S. enterica and Y. enterocolitica were isolated from broilers. The cdt genes were found in all Campylobacter isolates. In two aviaries, Campylobacter was isolated from both broilers and wild birds, however the mutual contamination among these birds has not been shown. This was the first report of Campylobacter isolation from Z. capensis and of Derby Salmonella serotype isolation from S. flaveola.(AU)

Physicochemical analysis of Permian coprolites from Brazil.

In this paper we performed the study of two coprolites (fossilized feces) collected from the exposed levels of the Pedra de Fogo Formation, Parnaiba Sedimentary Basin, and Rio do Rasto Formation, Paraná Sedimentary Basin, both of the Palaeozoic era (Permian age). They were characterized using X-ray diffractometry, infrared, Raman and energy dispersive spectroscopy techniques in order to aid our understanding of the processes of fossilization and to discuss issues related to the feeding habits of the animals which generated those coprolites, probably cartilaginous fishes. The results obtained using a multitechnique approach showed that although these coprolites are from different geological formations, 3000km away from each other, they show the same major crystalline phases and elemental composition. The main phases found were hydroxyapatite, silica, calcite and hematite, which lead to infer that those coprolites were formed under similar conditions and produced by a similar group of carnivore or omnivore fishes.

Real-time PCR detection of Didemnum perlucidum (Monniot, 1983) and Didemnum vexillum (Kott, 2002) in an applied routine marine biosecurity context.

Prevention and early detection are well recognized as the best strategies for minimizing the risks posed by nonindigenous species (NIS) that have the potential to become marine pests. Central to this is the ability to rapidly and accurately identify the presence of NIS, often from complex environmental samples like biofouling and ballast water. Molecular tools have been increasingly applied to assist with the identification of NIS and can prove particularly useful for taxonomically difficult groups like ascidians. In this study, we have developed real-time PCR assays suited to the specific identification of the ascidians Didemnum perlucidum and Didemnum vexillum. Despite being recognized as important global pests, this is the first time specific molecular detection methods have been developed that can support the early identification and detection of these species from a broad range of environmental sample types. These fast, robust and high-throughput assays represent powerful tools for routine marine biosecurity surveillance, as detection and confirmation of the early presence of species could assist in the timely establishment of emergency responses and control strategies. This study applied the developed assays to confirm the ability to detect Didemnid eDNA in water samples. While previous work has focused on detection of marine larvae from water samples, the development of real-time PCR assays specifically aimed at detecting eDNA of sessile invertebrate species in the marine environment represents a world first and a significant step forwards in applied marine biosecurity surveillance. Demonstrated success in the detection of D. perlucidum eDNA from water samples at sites where it could not be visually identified suggests value in incorporating such assays into biosecurity survey designs targeting Didemnid species.

Perspectives on carbon materials as powerful catalysts in continuous anaerobic bioreactors.

The catalytic effect of commercial microporous activated carbon (AC) and macroporous carbon nanotubes (CNT) is investigated in reductive bioreactions in continuous high rate anaerobic reactors, using the azo dye Acid Orange 10 (AO10) as model compound as electron acceptor and a mixture of VFA as electron donor. Size and concentration of carbon materials (CM) and hydraulic retention time (HRT) are assessed. CM increased the biological reduction rate of AO10, resulting in significantly higher colour removal, as compared to the control reactors. The highest efficiency, 98%, was achieved with a CNT diameter (d) lower than 0.25 mm, at a CNT concentration of 0.12 g per g of volatile solids (VS), a HRT of 10 h and resulted in a chemical oxygen demand (COD) removal of 85%. Reducing the HRT to 5 h, colour and COD removal in CM-mediated bioreactors were above 90% and 80%, respectively. In the control reactor, thought similar COD removal was achieved, AO10 decolourisation was just approximately 20%, demonstrating the ability of CM to significantly accelerate the reduction reactions in continuous bioreactors. AO10 reduction to the correspondent aromatic amines was proved by high performance liquid chromatography (HPLC). Colour decrease in the reactor treating a real effluent with CNT was the double comparatively to the reactor operated without CNT. The presence of AC in the reactor did not affect the microbial diversity, as compared to the control reactor, evidencing that the efficient reduction of AO10 was mainly due to AC rather than attributed to changes in the composition of the microbial communities.

Successful xenogeneic germ cell transplantation from Jundia catfish (Rhamdia quelen) into adult Nile tilapia (Oreochromis niloticus) testes.

Fish germ cell transplantation presents several important potential applications for aquaculture, including the preservation of germplasm from endangered fish species with high genetic and commercial values. Using this technique in studies developed in our laboratory with adult male Nile tilapias (Oreochromis niloticus), all the necessary procedures were successfully established, allowing the production of functional sperm and healthy progeny approximately 2months after allogeneic transplantation. In the present study, we evaluated the viability of the adult Nile tilapia testis to generate sperm after xenogeneic transplant of germ cells from sexually mature Jundia catfish (Rhamdia quelen) that belong to a different taxonomic order. Therefore, in order to investigate at different time-periods post-transplantation, the presence and development of donor PKH26 labeled catfish germ cells were followed in the tilapia seminiferous tubules. From 7 to 20days post-transplantation, only PKH26 labeled spermatogonia were observed, whereas spermatocytes at different stages of development were found at 70days. Germ cell transplantation success and progression of spermatogenesis were indicated by the presence of labeled PKH26 spermatids and sperm on days 90 and 120 post-transplantation, respectively. Confirming the presence of the catfish genetic material in the tilapia testis, all recipient tilapias evaluated (n=8) showed the genetic markers evaluated. Therefore, we demonstrated for the first time that the adult Nile tilapia testis offers the functional conditions for development of spermatogenesis with sperm production from a fish species belonging to a different order, which provides an important new venue for aquaculture advancement.

Real-time PCR validation of visually identified snapper Chrysophrys auratus (Sparidae) eggs.

In this study, a total of 212 eggs were visually identified as snapper Chrysophrys auratus. Real-time PCR confirmed visual identification in 69% of cases but corroboration varied widely among plankton samples. The use of molecular tools to support visual identification prior to adopting daily egg production stock assessment methods should be considered.

Introgression threatens the survival of the critically endangered freshwater crayfish Cherax tenuimanus (Decapoda: Parastacidae) in the wild.

Hybridization and genetic introgression following the introduction of exotic species can pose a significant threat to the survival of geographically restricted species. A remnant population of the critically endangered freshwater crayfish Cherax tenuimanus in the upper reaches of the Margaret River in southwestern Australia is under threat following the introduction and spread of its congener Cherax cainii. Here, we examine the extent of hybridization and introgression between the two species using twelve polymorphic microsatellite loci. Our study reveals there are three times more C. cainii than C. tenuimanus at our study site in the upper reaches of the Margaret River. There is also evidence of hybridization and introgression between C. tenuimanus and C. cainii at this site, with F1, F2 and backcrossed individuals identified. While interbreeding was confirmed in this study, our simulations suggest that the levels of introgression are much lower than would be expected under random mating, indicating partial reproductive barriers exist. Nevertheless, it is apparent that hybridization and introgression with C. cainii pose a serious threat to C. tenuimanus and their survival in the wild will require active adaptive management and continued genetic monitoring to evaluate management effectiveness.

Butyrylcholinesterase: K variant, plasma activity, molecular forms and rivastigmine treatment in Alzheimer's disease in a Southern Brazilian population.

Alzheimer's disease (AD) is a neurodegenerative disorder in which there is a decline of cholinergic function. The symptomatic AD treatment involves the use of ChEIs (cholinesterase inhibitors) as rivastigimine, a dual inhibitor. The human butyrylcholinesterase (BChE) is an enzyme that has specific roles in cholinergic neurotransmission and it has been associated with AD. In the serum, BChE is found in four main molecular forms: G1 (monomer); G1-ALB (monomer linked to albumin); G2 (dimer); and G4 (tetramer). The interaction between the products of BCHE gene and CHE2 locus results in CHE2 C5+ and CHE2 C5- phenotypes. CHE2 C5+ phenotype and BChE-K are factors that influence on BChE activity. This work aimed to verify the proportions of BChE molecular forms, total and relative activity in 139 AD patients and 139 elderly controls, taking into account K variant, CHE2 locus, rivastigmine treatment and clinical dementia rating (CDR) of AD patients. Phenotypic frequencies of CHE2 C5+ and frequency of the carriers of the K allele were similar between groups. Total BChE activity in plasma was significantly lower in AD patients than in elderly controls. Furthermore, we found that reduction on plasma BChE activity is associated directly with AD progression in AD patients and that rivastigmine treatment has a stronger effect on BChE activity within the CDR2 group. The reduction in BChE activity did not occur proportionally in all molecular forms. Multiple regression analysis results confirmed that AD acts as the main factor in plasma BChE activity reduction and that severe stages are related with an even greater reduction. These findings suggest that the reduction of total plasma BChE and relative BChE molecular forms activity in AD patients is probably associated with a feedback mechanism and provides a future perspective of using this enzyme as a possible plasmatic secondary marker for AD.

Induction of resistance by silicon in wheat plants to alate and apterous morphs of Sitobion avenae (Hemiptera: Aphididae).

Despite the knowledge about the effects of silicon augmenting antibiosis and nonpreference of plants by apterous aphids, few studies exist on such effects with alate aphids. This study evaluated the effects of silicon fertilization on the biology of alate and apterous morphs of Sitobion avenae (F.) (Hemiptera: Aphididae), and the effect on nonpreference by S. avenae alates for wheat plants with or without silicon fertilization. A method for rearing aphids on detached leaves was evaluated comparing the biology of apterous aphids reared on wheat leaf sections and on whole plants with and without silicon fertilization. Because the use of detached leaves was a reliable method, the effect of silicon fertilization on the biology of apterous and alate S. avenae was assessed using wheat leaf sections. Biological data of aphids were used to calculate a fertility life table. Finally, the effect of silicon fertilization on the nonpreference of alate aphids was carried out for both vegetative and reproductive phases of wheat. Thirty alate aphids were released in the center of a cage, and the number of aphids per whole plant with or without silicon fertilization was observed. Silicon fertilization induced antibiosis resistance in wheat plants to apterous morphs as shown by reduced fecundity, reproductive period, longevity, intrinsic rate of increase, and net reproductive rate; however, alates were unaffected. Plants that received silicon fertilization had fewer alate aphids in both the vegetative and reproductive phases. Thus, silicon fertilization can reduce colonization by alates, enhancing nonpreference resistance, and population growth of apterous S. avenae in wheat plants.

Percutaneous mitral valve repair in a high-risk Australian series.

BACKGROUND: The prognosis for patients with symptomatic, severe mitral regurgitation (MR) who have comorbidities precluding mitral valve surgery is poor. Treatment of MR using a percutaneous edge-to-edge technique may improve survival, quality of life and reduce hospitalisations. To date, there are few studies reporting outcomes after percutaneous mitral valve repair in high-risk patients and none reported from Australia. METHODS: The first 25 patients undergoing percutaneous mitral valve repair using the MitraClip in our Institution had follow-up to six months. These patients had severe, symptomatic MR and were deemed too high-risk for mitral valve surgery by a multidisciplinary heart team, including an interventional cardiologist and cardiothoracic surgeon. RESULTS: There were no peri-procedural deaths; the only peri-procedural morbidity was blood transfusion in three patients. Three patients had died at six months and there were six readmissions to hospital. There was a significant improvement in heart failure symptoms, 6-minute walk test and quality of life at six months. There was a significant improvement in the proportion of patients with MR ≤2+, but no significant change in other echocardiographic parameters. CONCLUSIONS: Percutaneous mitral valve repair is safe in patients at high-risk for surgery, and improves symptoms and quality of life.

Pedigree studies and evaluation of risk factors of breast cancer in Goa.

BACKGROUND: Incidence of breast cancer (BC) is increasing in most of the countries, including the areas which have had previously low rates. AIM: The aim of this prospective study was to analyze the pedigrees of the patients for detecting hereditary factor prevalence and to investigate the possible risk factors associated with BC in a sample population from Goa. MATERIALS AND METHODS: A prospective analysis was performed for 95 BC patients between 2011 and 2012. For assessing the risk factors, a proforma was designed and the necessary data was collected by interview. The process of collecting family history for drawing the pedigree included interviewing the informant. STATISTICAL ANALYSIS USED: Online calculators of statistics were used for standard deviation at www.easycalculation.com and fishers test at www.graphpad.com. RESULTS: High frequency of BC was revealed in the sample population from Goa. This could be attributed to the changes in reproductive patterns, physical inactivity and obesity, or general increase in BC awareness. Factors which did not influence the frequency of BC in the sample population include parity, oral contraceptives, alcohol consumption, occupation, exercise, and nutritional supplement. High incidence of family history of 168/1000 individuals was observed in the present study. CONCLUSIONS: Proper management of BC is possible after assessment of cumulative risk of BC in females by a thorough study of both environmental and genetic factors. Cumulative risk can be greatly reduced by controlling the environmental risk.

Antibiosis and non-preference of Sitobion avenae (F.) (Hemiptera: Aphididae) on leaves and ears of commercial cultivars of wheat (Triticum aestivum).

Little is known on the resistance of wheat cultivars to Sitobion avenae (F.) in Brazil. The goal of this work was to assess the behavior and biology of S. avenae on four commercial wheat cultivars to verify the existence of resistance by antibiosis in leaves and ears and non-preference in the ears. The smallest net fecundity rates of S. avenae in wheat leaves have been found in the cultivars Embrapa 22 and BRS264, which did not differ between themselves. The intrinsic rate of increase of S. avenae was smaller in leaves of Embrapa 22 than in cultivars BRS254 and BRS Timbaúva. The smallest net fecundity rates of S. avenae in wheat ears were observed in the cultivars BRS254 and Embrapa 22. The intrinsic rate of increase of the aphid in the ear of cultivar Embrapa 22 was smaller than in BRS Timbaúva and BRS264, but did not differ from BRS254. The organ of the wheat plant in which the aphid was reared influences antibiosis resistance, but the cultivar BRS Timbaúva was considered susceptible and Embrapa 22 resistant to S. avenae in both plant organs tested. Ears of wheat cultivars tested did not show differences in the mechanism of resistance by non-preference to S. avenae.

Polybrominated diphenyl ethers (PBDES) and polychlorinated biphenyls (PCBS) in mussels and two fish species from the estuary of the Guanabara Bay, Southeastern Brazil.

The present investigation aimed to analyze PBDE and PCB contamination in mussels (Perna perna) and two commercially important fish species, croaker (Micropogonias furnieri) and mullet (Mugil liza), in the Guanabara Bay, the most important Brazilian estuary, by gas chromatography coupled to mass spectrometry, in order to further knowledge regarding these compounds in the southern hemisphere. This is also the first report of PBDE in this mussel species in the Guanabara Bay. Fish were captured in September (dry season, winter) and March (wet season, summer) 2007 and September 2008. Mussels were collected in August (dry season, winter) 2006, in February (wet season, summer) 2007, and in August 2007 (winter). The results show that all samples showed higher PCB contamination when compared to other ecosystems around the world. On the other hand, PBDEs presented lower concentrations in 41 % of the samples. Croakers presented the highest PCB and PBDE levels, with mullet showing intermediary values and mussels, the lowest.