Maximizing use of existing carcinogenicity data to support acceptable intake levels for mutagenic impurities in pharmaceuticals: Learnings from N-nitrosamine case studies.

The unexpected finding of N-nitrosamine (NA) impurities in many pharmaceutical products raised significant challenges for industry and regulators. In addition to well-studied small molecular weight NAs, many of which are potent rodent carcinogens, novel NAs associated with active pharmaceutical ingredients have been found, many of which have limited or no safety data. A tiered approach to establishing Acceptable Intake (AI) limits for NA impurities has been established using chemical-specific data, read-across, or a class-specific TTC limit. There are ∼140 NAs with some rodent carcinogenicity data, but much of it is older and does not meet current guidelines for what constitutes a 'robust' bioassay. Nevertheless, these data are an important source of information to ensure the best science is used for assessing NA impurities and assuring consumer safety while minimizing impact that can lead to drug shortages. We present several strategies to maximize the use of imperfect data including using a lower confidence limit on a rodent TD50, and leveraging data from multiple NAs. Information on the chemical structure known to impact potency can also support development of an AI or potentially conclude that a particular NA does not fall in the cohort of concern for potent carcinogenicity.

The effect of filling technique on the cuspal strain, polymerization shrinkage stress, enamel crack formation and depth of cure of restored molars.

OBJECTIVE: Evaluate the effect of different restorative filling techniques on the residual shrinkage stress (ShrS), cuspal strain (CS), depth of cure (DC), and enamel crack formation (Ec) in molars with MOD restorations. METHODS: Post-gel shrinkage, elastic modulus, compressive and diametral tensile strength of the Filtek One Bulk Fill composite were calculated. Sixty molars with MOD preparations were restored using four filling techniques: Bulk; Horizontal; Oblique; Natural enamel and dentin substitution (NEDS) technique. CS was measured using a strain gauge (n = 10). The DC (n = 5) was measured using Knoop hardness. Shrinkage stress/strain was analyzed using 3D finite element analysis. The Ec analysis was carried out by transillumination. Two-way ANOVA with repeated measures and Tukey's HSD test (α = 0.05) was performed for the CS data. Two-Way ANOVA and Tukey's HSD test was performed for the DC data (α = 0.05). RESULTS: CS was higher at the lingual cusp for the horizontal and NEDS technique. No statistical difference was found between the buccal and lingual CS values for the Bulk (p = 0.367) or Oblique techniques (p = 0.192). CS values were lower for the Bulk. More enamel cracks were found for the Bulk. DC was lower at 4 mm regardless the filling technique. The Horizontal showed the highest ShrS values. The Bulk generated the lower ShrS values. SIGNIFICANCE: A Bulk technique caused the lowest shrinkage stress/strain. An Oblique technique yielded the best balance between stress, strain and crack formation. NEDS technique is a good alternative to decrease the number of increments while maintaining the stress levels nearby the Oblique technique.

Small understorey trees have greater capacity than canopy trees to adjust hydraulic traits following prolonged experimental drought in a tropical forest.

Future climate change predictions for tropical forests highlight increased frequency and intensity of extreme drought events. However, it remains unclear whether large and small trees have differential strategies to tolerate drought due to the different niches they occupy. The future of tropical forests is ultimately dependent on the capacity of small trees (<10 cm in diameter) to adjust their hydraulic system to tolerate drought. To address this question, we evaluated whether the drought tolerance of neotropical small trees can adjust to experimental water stress and was different from tall trees. We measured multiple drought resistance-related hydraulic traits across nine common neotropical genera at the world's longest-running tropical forest throughfall-exclusion experiment and compared their responses with surviving large canopy trees. Small understorey trees in both the control and the throughfall-exclusion treatment had lower minimum stomatal conductance and maximum hydraulic leaf-specific conductivity relative to large trees of the same genera, as well as a greater hydraulic safety margin (HSM), percentage loss of conductivity and embolism resistance, demonstrating that they occupy a distinct hydraulic niche. Surprisingly, in response to the drought treatment, small trees increased specific hydraulic conductivity by 56.3% and leaf:sapwood area ratio by 45.6%. The greater HSM of small understorey trees relative to large canopy trees likely enabled them to adjust other aspects of their hydraulic systems to increase hydraulic conductivity and take advantage of increases in light availability in the understorey resulting from the drought-induced mortality of canopy trees. Our results demonstrate that differences in hydraulic strategies between small understorey and large canopy trees drive hydraulic niche segregation. Small understorey trees can adjust their hydraulic systems in response to changes in water and light availability, indicating that natural regeneration of tropical forests following long-term drought may be possible.

The External Morphology of the Eggs of Culex (Culex) saltanensis (Diptera: Culicidae) Under Scanning Electron Microscopy.

The aim of the present study was to describe the morphology of the eggs of Culex (Culex) saltanensis Dyar that occurs in the Neotropical region. Eggs of the Cx. (Cux.) saltanensis were collected at the Mata Atlântica FIOCRUZ campus, fixed in 1% osmium tetroxide, prepared for mounting on metal supports, observed under a scanning electron microscope, and described morphologically. The eggs had a coniform shape with a length of approximately 0.5 mm (505-510 µm) and a width in the median portion of 117 µm (113-123 µm). Upper portion is lined with tubers of irregular shape and varying sizes (0.64-1.31 µm), located on a cross-linked matrix forming bands observed under optical microscopy. The micropyle is encased in a necklace of approximately 6.6-µm plates arranged in a flower-like shape. Comparing Cx. (Cux.) saltanensis eggs with several species of different genera, important divergent characteristics can be observed. However, this study points to the need for new descriptions of eggs of species belonging to the same subgenus in order to analyze if there will be differences between them. Culex (Cux.) saltanensis eggs have particular characteristics not observed in eggs of other Culicidae genera.

Avaliação neurocomportamental e níveis de acetilcolinesterase cerebral em ratos expostos subcronicamente ao fipronil / Neurobehavioral assessment and brain acetylcholinesterase levels in rats subchronically exposed to fipronil

O fipronil é um inseticida de toxicidade seletiva amplamente empregado na agricultura e na medicina veterinária. Porém, há relatos de efeitos neurotóxicos dessa substância, que geram prejuízos para vertebrados. Avaliou-se a atividade locomotora, a coordenação motora e a atividade da enzima acetilcolinesterase cerebral em ratos expostos ao fipronil. Ratos Wistar machos adultos (n=15) receberam fipronil em dose de 30mg/kg, por via oral, durante 15 dias; o grupo controle (n=15) foi tratado com solução fisiológica, por via oral, no mesmo período. No 16° dia de experimentação, os animais foram submetidos aos testes de arena de campo aberto e hole board. No 17° dia, foram anestesiados e eutanasiados, procedendo-se à coleta de órgãos, e posteriormente foi feita a avaliação da AChE cerebral. A exposição ao fipronil não provocou alterações significativas sobre a coordenação motora e a atividade locomotora, porém gerou inibição significativa da atividade da acetilcolinesterase cerebral. Esses achados sugerem que o fipronil pode provocar efeitos neurotóxicos em curto prazo, os quais podem ser exacerbados caso a exposição seja prolongada.(AU)

Fipronil is a selective-toxicity insecticide widely used in agriculture and veterinary medicine. However, there are reports of neurotoxic effects of this substance, causing damages to vertebrates. We evaluated the locomotor activity, motor coordination and the activity of brain acetylcholinesterase in rats exposed to fipronil. Adult male Wistar rats (n= 15) received fipronil at a dose of 30mg/kg orally for 15 days; the Control group (n= 15) was treated with oral solution in the same period. On the 16th day of experimentation, the animals were submitted to the open field arena test and hole-board test. On the 17th day, they were anesthetized and euthanized, and organs were collected, and subsequently brain AChE was evaluated. Exposure to fipronil yielded no significant changes on motor coordination and locomotor activity but caused significant inhibition of brain acetylcholinesterase activity. These findings suggest that fipronil may cause short-term neurotoxic effects, which may be exacerbated if exposure is prolonged.(AU)

Imunodetecção de Toxoplasma gondii em tecido placentário de cabras naturalmente infectadas / Immunodetection of Toxoplasma gondii in placenta tissue of naturally infected goats

A imuno-histoquímica (IHQ) é considerada uma ferramenta rápida e precisa para a identificação de protozoários, como Toxoplasma gondii, em tecidos fetais e placentários. Neste estudo foi avaliada a imunodetecção de Toxoplasma gondii em tecido placentário de cabras naturalmente infectadas. Foram coletadas e analisadas 80 amostras de placentas de cabras procedentes de único rebanho com sorologia positiva para T. gondii na técnica de ELISA. Na histopatologia, 27/80 amostras apresentaram lesões sugestivas de infecção por protozoários. Após a avaliação histopatológica, procedeu-se à realização da técnica de imuno-histoquímica, obtendo-se 85,2% (23/27) de amostras com marcação positiva. A imunodetecção ocorreu no epitélio de revestimento das vilosidades coriônicas e foi classificada de acordo com o grau de intensidade da imunomarcação. Também foi evidenciada imunomarcação no interior dos vasos sanguíneos fetais em 8,69% (2/23) das amostras. Este estudo demonstrou que a técnica de IHQ se comportou como uma ferramenta valiosa no diagnóstico da infeção por T. gondii em tecido placentário de cabras naturalmente infectadas e complementou, de forma decisiva, o diagnóstico, além de agregar maior valor aos resultados obtidos nas análises histopatológica e sorológica.(AU)

Immunohistochemistry (IHC) is considered to be a rapid and accurate tool for the identification of protozoa such as Toxoplasma gondii in fetal and placental tissues. In this study, we evaluated the immunodetection of Toxoplasma gondii in placental tissue from naturally infected goats. A total of 80 samples of goat placentas from a single herd with positive ELISA serology for T. gondii were collected and analyzed. In the histopathology, 27/80 samples presented lesions suggestive of protozoal infection. After the histopathological evaluation, the immunohistochemistry technique was performed, obtaining 85.2% (23/27) of samples with positive marking. Immunodetection occurred in the lining epithelium of the chorionic villi and was classified according to the degree of intensity of the immunostaining. Immunostaining within the fetal blood vessels was also evidenced in 8.69% (2/23) of the samples. This study demonstrated that the IHQ technique behaved as a valuable tool in the diagnosis of T. gondii infection in placental tissue of naturally infected goats completing the diagnosis in a decisive way and adding greater value to the results obtained in the histopathological and serological analysis.(AU)

Epidemiologic Profile of Patients Transplanted With Hematopoietic Stem Cells in a Reference Service in the State of Rio Grande do Norte, Brazil.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) consists of the intravenous infusion of healthy hematopoietic stem cells to restore the medullary and immunologic function of patients affected by a series of hematologic, oncologic, immunologic, malignant and nonmalignant inherited or acquired diseases, with the possibility of cure or increase of disease-free survival. OBJECTIVE: To characterize the epidemiologic profile and the cases of death of patients who underwent HSCT. METHODS: This is a cohort quantitative study, nested with a retrospective, descriptive, and analytical study of a hospital-based cohort that included the patients who underwent HSCT at a referral service in the state of Rio Grande do Norte, a region of northeastern Brazil. RESULTS: There was a slight male prevalence (52.94%), the age of the patients ranged from 2 to 73 years old, 18.38% were brown, 47.06% were married, 15.07% were students, 78.31% had a diagnosis of multiple myeloma, 93.38% developed gastrointestinal toxicities, all patients received chemotherapeutic treatment, 54.78% had allogeneic HSCT, and the cause of the most recorded deaths was septic shock (48.19%). CONCLUSIONS: This study showed relevant scientific evidence on the clinical and epidemiologic profile of patients who underwent HSCT. In general, sociodemographic data are similar to national and international research results.

Aspecto médico veterinário legal das lesões em aves silvestres promovidas por colisões com aeronaves / Medico-legal veterinary aspect of lesions in bird strike

The objective of this study was to describe lesions in four birds, victims of collisions with aircraft, coming from the International Airport of Recife/Guararapes Gilberto Freyre, Pernambuco, Brazil. Contused wounds were predominant in birds in this study, characterized by the presence of fractures, bruises and hematomas and justified by the blunt action promoted by the type of vulnerant agent involved (aircraft). The analysis under medico-legal veterinary aspect of lesions in bird strike is essential, because in addition to the attempt to establish a standard for differentiating the aircraft lesions, it can guide the bird strike hazard management programs at airports, since the necropsy allows the identification of the species involved or at least facilitates the obtaining biological material for identification.(AU)

Anticorpos anti-Toxoplasma gondii em carcarás (Caracara plancus) procedentes da região aeroportuária do Recife, Pernambuco, Brasil / Antibodies to Toxoplasma gondii in Crested Caracara (Caracara plancus) from Recife Airport, Pernambuco, Brazil

Objetivou-se com este estudo pesquisar a ocorrência de anticorpos anti-Toxoplasma gondii em carcarás (Caracara plancus) capturados no Aeroporto Internacional do Recife/Guararapes Gilberto Freyre, Pernambuco, Brasil. Foram analisadas 115 amostras de soros sanguíneos pelo teste de aglutinação modificada (IgG, MAT≥25) utilizando taquizoítos inativados em formalina. Do total de amostras analisadas, 5,21% (6/115) foram positivas para presença de anticorpos anti-T. gondii, 16,67% com título 1:25 (1/06) e 83,33% (5/06) com título 1:50. A ocorrência de anticorpos em carcarás procedentes de região aeroportuária fomenta a preocupação em relação a aspectos ainda pouco elucidados, relacionados principalmente à inserção de aves silvestres na cadeia epidemiológica da toxoplasmose conectada à ação antrópica, tornando próxima a interação entre animais silvestres, domésticos e o homem. Dessa forma, é notória a necessidade de estudos relacionados à dinâmica de transmissão entre os diferentes genótipos existentes nessa tríade e sua relação com o meio ambiente, a fim de determinar a influência dessa espécie animal na cadeia epidemiológica da toxoplasmose.(AU)

The objective of this study was to investigate the occurrence of antibodies against Toxoplasma gondii in carcarás (Caracara plancus) captured in the Recife/Guararapes Gilberto Freyre International Airport, in the State of Pernambuco, Brazil. 115 samples of blood sera were tested by the Modified Agglutination Test technique (IgG, MAT > 25) using tachyzoites inactivated in formalin. Of the total of the analyzed samples, 5,21% (6/115) were positive for the presence of antibodies against T. gondii, 16,67% with a titer of 1:25 (1/06) and 83,33% (5/06) with a titration of 1:50. The occurrence of antibodies in caracaras coming from airport region generate concern about aspects still poorly understood, mainly related to the inclusion of wild birds in the epidemiological chain of toxoplasmosis connected to human action, making close interaction between wild animals, domestic and man. Thus, the need for studies related to the dynamics of transmission between the different existing genotypes in this triad is evident as is its relationship with the environment to determine the influence of this animal species in the epidemiological chain of toxoplasmosis.(AU)

Genetic Diversity of Urban Camponotus Mayr (Hymenoptera: Formicidae) Ants Revealed by Capture of Alates and DNA Sequencing.

The Camponotus Mayr genus of carpenter ants is one of the largest in species number and widely represented in the Neotropical Region. Most species are generalists and capable of exploiting diverse habitats including urban environments. Urban green areas can act as a repository of regional biodiversity, thus we investigated whether this is valid for the largest city in South America. We compared the richness of Camponotus spp. in two green areas in regions with distinct urbanization profiles and also with previous surveys made in smaller cities and in natural areas of the original Atlantic Forest. Besides the usual capture of worker specimens, we included capture of alates to improve the species richness sampling. Morphological identification of Camponotus spp. is challenging, even more when alates are included. To assist in specimen identification, we performed DNA sequencing of mitochondrial and nuclear markers. The richness observed in the less stressed urban area was higher than in the more stressed one. Camponotus spp. reported in natural areas are largely represented in the urban area. DNA sequencing for specimen identification is hampered by the lack of corresponding sequences in the GenBank, but it helped to associate workers and alates of the same species and indicated the existence of cryptic species in the genus. Capture of alates allowed detection of several species for which workers were not sampled; therefore, it is a valuable tool for surveying diversity of Camponotus or other ant taxa with arboreal or hypogeic habits.

Detecção molecular e isolamento de Mycoplasma spp. em psitacídeos no estado de Pernambuco, Brasil / Molecular detection and isolation of Mycoplasma spp. in psittacines in Pernambuco state, Brazil

Objetivou-se com este estudo investigar a ocorrência de Mycoplasma spp., Mycoplasma galissepticum (MG) e Mycoplasma synoviae (MS) em psitacídeos de cativeiro localizado no estado de Pernambuco, Brasil. Foram estudadas 85 aves provenientes do Parque Estadual Dois Irmãos, localizado no estado do Pernambuco, Brasil. De cada psitacídeo analisado foram obtidas três amostras por meio de swabs da cloaca, palato e conjuntiva totalizando 255 amostras. As amostras coletadas foram submetidas à extração de DNA e à reação em cadeia da polimerase (PCR), sendo as positivas submetidas ao isolamento em ágar Frey. O DNA de Mycoplasma spp. foi detectado em 16,47% (14/85) dos psitacídeos estudados. Das 255 amostras analisadas, 6,66% (17/255) foram positivas para a presença de Mycoplasma spp., sendo 41,18% (7/17) provenientes da conjuntiva, 35,29% (6/17) do palato e 23,53% (4/17) da cloaca. Nenhuma amostra foi positiva para MG ou MS na PCR. Os resultados obtidos permitem confirmar a presença do DNA de Mycoplasma spp. em conjuntiva, palato e cloaca nas aves estudadas. Foram detectadas colônias semelhantes a membros da classe Mollicutes em 17,64% das amostras (3/17). Esse é o primeiro relato da presença de Mycoplasma spp. em psitacídeos de cativeiro no Nordeste do Brasil.

The aim of this study was to investigate the occurrence of Mycoplasma spp., Mycoplasma galissepticum (MG) and Mycoplasma synoviae (MS) in captive psittacines. Eighty-five wild birds from Parque Estadual Dois Irmãos, Pernambuco state, northeastern Brazil, were used. From each psittacid analyzed three samples were obtained through cloaca, palate and conjunctiva swabs, totaling 255 samples. Samples collected were submitted to DNA extraction and Polimerase Chain Reaction (PCR). Mycoplasma spp. DNA was detected in 16.47% (14/85) of psittacines studied. From 255 samples, 6.66% (17/255) were positive for Mycoplasma spp.: 41.18% (7/17) of positivity in conjunctiva, 35.29% (6/17) in palate and 23.53% (4/17) in cloaca. There was no positive sample for MG or MS in PCR. Similar colonies were found for members of the Mollicutes Class in 17.64% of the samples (3/17). The results confirmed Mycoplasma spp. DNA in conjunctiva, palate and cloaca from the wild birds analyzed. This is the first record of Mycoplasma spp. in captive psittacines from northeastern Brazil.

Death from drought in tropical forests is triggered by hydraulics not carbon starvation.

Drought threatens tropical rainforests over seasonal to decadal timescales, but the drivers of tree mortality following drought remain poorly understood. It has been suggested that reduced availability of non-structural carbohydrates (NSC) critically increases mortality risk through insufficient carbon supply to metabolism ('carbon starvation'). However, little is known about how NSC stores are affected by drought, especially over the long term, and whether they are more important than hydraulic processes in determining drought-induced mortality. Using data from the world's longest-running experimental drought study in tropical rainforest (in the Brazilian Amazon), we test whether carbon starvation or deterioration of the water-conducting pathways from soil to leaf trigger tree mortality. Biomass loss from mortality in the experimentally droughted forest increased substantially after >10 years of reduced soil moisture availability. The mortality signal was dominated by the death of large trees, which were at a much greater risk of hydraulic deterioration than smaller trees. However, we find no evidence that the droughted trees suffered carbon starvation, as their NSC concentrations were similar to those of non-droughted trees, and growth rates did not decline in either living or dying trees. Our results indicate that hydraulics, rather than carbon starvation, triggers tree death from drought in tropical rainforest.

Characterization of Hybrid Bioactive Glass-polyvinyl Alcohol Scaffolds Containing a PTHrP-derived Pentapeptide as Implants for Tissue Engineering Applications.

Hybrid foam (BG-PVA) with 50 % Bioactive glass (BG) and 50 % polyvinyl alcohol (PVA) was prepared by sol-gel process to produce scaffolds for bone tissue engineering. The pore structure of hydrated foams was evaluated by 3-D confocal microscopy, confirming 70% porosity and interconnected macroporous network. In this study, we assessed the putative advantage of coating with osteostatin pentapeptide into BG-PVA hybrid scaffolds to improve their bioactivity. In vitro cell culture experiments were performed using mouse pre-osteoblastic MC3T3-E1 cell line. The exposure to osteostatin loaded-BG-PVA scaffolds increase cell proliferation in contrast with the unloaded scaffolds. An in vivo study was selected to implant BG-PVA scaffolds, non-coated (Group A) or coated (Group B) with osteostatin into non critical bone defect at rabbit femur. Both groups showed new compact bone formation on implant surface, with lamellae disposed around a haversian canal forming osteons-like structure. We observed signs of inflammation around the implanted unloaded scaffold at one month, but resolved at 3 months. This early inflammation did not occur in Group B; supporting the notion that osteostatin may act as anti-inflammatory inhibitor. On the other hand, Group B showed increased bone formation, as depicted by many new trabeculae partly mineralized in the implant regenerating area, incipient at 1 month and more evident at 3 months after implantation. PVA/BG hybrid scaffolds present a porous structure suitable to support osteoblast proliferation and differentiation. Our in vitro and in vivo findings indicate that osteostatin coating improves the osteogenic features of these scaffolds.

Genetic control of leaf curl in maize.

Among the many implications of climatic change on agriculture, drought is expected to continue to have a major impact on agribusinesses. Leaf curling is an anatomical characteristic that might be potentially used to enhance plant tolerance to water deficit. Hence, we aimed to study the genetic control of leaf curl in maize. From 2 contrasting inbred lines for the trait, generations F1, F2, and the backcrosses were obtained. All of these generations were evaluated in a randomized block design with 2 replicates. Leaf curl samples were collected from 3 leaves above the first ear at the tasseling stage, and quantified by dividing the width of the leaf blade with natural curling against its extended width. The mean and variance components were estimated by the weighted least square method. It was found that the trait studied has predominance of the additive effects, with genetic control being attributed to few genes that favor selection and exhibit minimal influence from the environment.

Effect of sorghum tannins in sheep fed with high-concentrate diets / Efeito do tanino do sorgo em dietas de ovinos com alto concentrado

The aim of this study was to evaluate the nutritional value of three sorghum cultivars with different concentrations of condensed tannins in sheep diets. Six adult sheep (LW=56kg) with rumen and duodenal fistulas were assigned to experimental groups using two 3x3 Latin Square designs. The diets were formulated using three sorghum cultivars: LTC (low-tannin cultivar), MTC (medium-tannin cultivar) and HTC (high-tannin cultivar). Microbial nitrogen (MN) concentration in the duodenum was measured using a 15N trace technique. LTC, MTC and HTC diets presented values of 788, 722 and 747 (SE=20.6) g kg-1 for dry matter digestibility and 633, 535 and 530 (SE=35.8) g/kg for crude protein digestibility. The LTC diet was significantly different from the other diets (P<0.05). The nitrogen balance was 145.5, 94.8 and 83.8g kg-1 (SE=13.0) for LTC, MTC and HTC, respectively, with LTC showing greater nitrogen retention (P<0.05). Values obtained for MN in the digesta were 301, 364 and 469 (SE=30.6) g kg-1 for LTC, MTC and HTC, respectively, and there was no statistical difference (P>0.05) between the diets. The presence of condensed tannins in the sorghum interfered with the sheep's nitrogen retention; however, the microbial protein supply to the duodenum of the animals was not inhibited.

O objetivo do presente estudo foi avaliar o valor nutricional de três cultivares de sorgo com diferentes concentrações de tanino condensado em dietas de ovinos. Seis carneiros machos, adultos, castrados, canulados no rúmen e duodeno foram divididos em três grupos experimentais, em um delineamento em quadrado latino 3x3. Os tratamentos foram representados por três dietas experimentais contendo diferentes cultivares de grão de sorgo: LTC (cultivar com baixa concentração de tanino), MTC (cultivar com concentração média de tanino) e HTC (cultivar com concentração alta de tanino). As concentrações de nitrogênio de origem microbiana no duodeno (MN) foram mensuradas pela técnica de marcador isótopo estável 15N. As dietas LTC, MTC e HTC apresentaram valores de 788, 722 e 747g.kg-1 (EP=20,6) para a digestibilidade aparente da matéria seca e 633, 535 e 530g.kg-1 (EP=35,8) para a digestibilidade aparente da proteína bruta. A dieta LTC apresentou diferença significativa quando comparada às demais dietas para as avaliações de digestibilidade (P<0,05). Os valores encontrados para o balanço de nitrogênio foram de 145,5; 94,8 e 83,8g.kg-1 (EP=13,0) para LTC, MCT e LTC, respectivamente, sendo a dieta LTC a que apresentou maior retenção de nitrogênio (P<0,05). Os valores obtidos para MN na digesta foram de 301, 364 e 469 para LTC, MTC e HTC, respectivamente, e não apresentaram diferenças estatísticas (P>0,05). As diferentes concentrações de taninos condensados nos cultivares de sorgo resultaram em melhorias na digestibilidade e retenção de nitrogênio das dietas, entretanto o fluxo de proteína microbiana não foi inibido.

Estimativa do intervalo pós-morte em um canino (Canis lupus familiaris Linnaeus 1758) pela entomologia forense em Cabedelo-PB, Brasil: relato de caso / Estimate of postmortem interval through forensic entomology in a canine (Canis lupus familiaris Linnaeus 1758) in Cabedelo-PB, Brazil: case report

O intervalo pós-morte (IPM) é um instrumento importante de diagnóstico relacionado à prática forense. O uso de insetos tem sido relatado como um modo eficiente para estimá-lo, quando o cadáver encontra-se em estágio avançado de decomposição. Objetivou-se com este trabalho estimar o IPM com base em evidências entomológicas em um canino. Foram coletadas larvas de moscas no cadáver e encaminhadas ao laboratório de entomologia, onde foram criadas e eclodiram adultos da espécie Chrysomya albiceps (Wiedemann, 1819). Somando-se os dados abióticos de temperatura e umidade relativa do local de coleta e do local de criação, estimou-se um IPM mínimo de 3,34 dias do momento da postura dos ovos pelas moscas até a coleta das larvas. Com base nos resultados obtidos, conclui-se que a entomologia forense, como ferramenta para estimativa do IPM, mostrou-se eficaz e determinante na elucidação do caso em questão.

The postmortem interval (PMI) is an important tool for diagnosis related to the forensic practice. The use of insects has proved to be an efficient diagnosis tool when the cadaver is in advanced decomposition stage. The objective of this work was to estimate PMI based on entomological evidence in a canine. Fly larvae was collected from the cadaver and forwarded to the Entomology laboratory. The fly larvae were reared and hatched adults of Chrysomya albiceps (Wiedemann 1819). With these insects and the abiotic data of temperature and relative humidity, from the places of collection and rearing larvae, a minimum PMI of 3.34 days from the laying of eggs by the flies until the time that we collected the larvae was obtained. The results show that Forensic Entomology as tool to estimate PMI is decisive and effective in the elucidation of the case.

Shifts in plant respiration and carbon use efficiency at a large-scale drought experiment in the eastern Amazon.

*The effects of drought on the Amazon rainforest are potentially large but remain poorly understood. Here, carbon (C) cycling after 5 yr of a large-scale through-fall exclusion (TFE) experiment excluding about 50% of incident rainfall from an eastern Amazon rainforest was compared with a nearby control plot. *Principal C stocks and fluxes were intensively measured in 2005. Additional minor components were either quantified in later site measurements or derived from the available literature. *Total ecosystem respiration (R(eco)) and total plant C expenditure (PCE, the sum of net primary productivity (NPP) and autotrophic respiration (R(auto))), were elevated on the TFE plot relative to the control. The increase in PCE and R(eco) was mainly caused by a rise in R(auto) from foliage and roots. Heterotrophic respiration did not differ substantially between plots. NPP was 2.4 +/- 1.4 t C ha(-1) yr(-1) lower on the TFE than the control. Ecosystem carbon use efficiency, the proportion of PCE invested in NPP, was lower in the TFE plot (0.24 +/- 0.04) than in the control (0.32 +/- 0.04). *Drought caused by the TFE treatment appeared to drive fundamental shifts in ecosystem C cycling with potentially important consequences for long-term forest C storage.

Production of citreoviridin by Penicillium citreonigrum strains associated with rice consumption and beriberi cases in the Maranhão State, Brazil.

The aim of this study was to determine the levels of Penicillium citreonigrum and citreoviridin present in rice samples from Maranhão State, Brazil, where an outbreak of beriberi was reported and 32 deaths occurred (7% of the notified cases died in 2006). The ability of P. citreonigrum to produce citreoviridin was assessed, and a total of 420 samples of 21 different kinds of rice were collected. Mycobiota isolation and identification, the ability of citreoviridin strains to produce toxin, and the natural occurrence of citreoviridin were established. Rice samples were found to have high fungal counts and showed increasing levels from 2004 to 2007 harvest years. The most frequent genus was Aspergillus followed by Penicillium and Cladosporium. Ten out of eleven strains of P. citreonigrum were able to produce citreoviridin. Three rice samples had levels of citreoviridin ranging from 12 to 96.7 ng g(-1), and two bran samples had levels of 128 and 254 ng g(-1). These samples contaminated with P. citreonigrum and citreoviridin were involved in the beriberi cases from Maranhão State. Monitoring rice for mycotoxins in areas where this substrate is the basic food is crucial to prevent outbreaks like the one reported in this study, to improve management practice, and to diminish exposure risk of humans to these harmful toxins.

Spatial patterns in the brood combs of Nannotrigona testaceicornis (Hymenoptera: Meliponinae): male clusters.

Genetic models of sex and caste determination in eusocial stingless bees suggest specific patterns of male, worker and gyne cell distribution in the brood comb. Conflict between queen and laying workers over male parentage and center-periphery gradients of conditions, such as food and temperature, could also contribute to non-random spatial configuration. We converted the positions of the hexagonal cells in a brood comb to Cartesian coordinates, labeled by sex or caste of the individuals inside. To detect and locate clustered patterns, the mapped brood combs were evaluated by indexes of dispersion (MMC, mean distance of cells of a given category from their centroid) and eccentricity (DMB, distance between this centroid and the overall brood comb centroid) that we developed. After randomizing the labels and recalculating the indexes, we calculated probabilities that the original values had been generated by chance. We created sets of binary brood combs in which males were aggregated, regularly or randomly distributed among females. These stylized maps were used to describe the power of MMC and DMB, and they were applied to evaluate the male distribution in the sampled Nannotrigona testaceicornis brood combs. MMC was very sensitive to slight deviations from a perfectly rounded clump; DMB detected any asymmetry in the location of these compact to fuzzy clusters. Six of the 82 brood combs of N. testaceicornis that we analyzed had more than nine males, distributed according to variations in spatial patterns, as indicated by the two indexes.

Produção de mudas de Aloysia gratissima (Gillies & Hook. ) Tronc. por meio da propagação sexuada e assexuada / Aloysia gratissima (Gillies & Hook. ) Tronc. seedling production through sexual and asexual propagation

A alfazema-do-Brasil é planta de importância medicinal, como produtora de terpenos. A principal descrição etnofarmaco-botânica aponta como sendo eficaz para infecções brônquicas, pulmonares e da bexiga. O objetivo do trabalho foi estudar a propagação de A. gratissima visando a obtenção de mudas. Na propagação sexuada estudou-se a influência da temperatura na presença e ausência de luz e três épocas de coleta das sementes (março, junho e setembro). Na propagação via semente foram testados três diferentes substratos (areia, palha de arroz carbonizada, Plantmax®). Na propagação vegetativa foram testados dois tipos de estacas (herbáceas e semi-lenhosas) e de dois substratos (areia e Plantmax®). Os resultados indicaram que na propagação sexuada, a germinação das sementes foi maior nas temperaturas constantes de 20 e 25°C, e a melhor época de coleta de sementes foi em março. O substrato comercial mostrou-se superior para o crescimento das plântulas, atingindo 93,25 por cento de emergência das sementes e 100 por cento de sobrevivência. Para a propagação assexuada, as estacas herbáceas em substrato comercial e areia apresentaram 96 e 95 por cento de enraizamento, respectivamente.

Brazilian-lavender is a medicinally important plant since it produces terpenes. As regards ethnopharmacology, it is mainly efficient against bronchial, lung and bladder infections. The aim of this work was to study Aloysia gratissima propagation for seedling production. In sexual propagation, temperature influence in the presence and absence of light and three seed harvesting times (March, June, and September) were studied. Three different substrates (sand, carbonized rice husk, Plantmax®) were also evaluated for seed germination. In vegetative propagation, two cutting types (herbaceous and semihardwood) and two substrates (sand, Plantmax®) were tested. Seed germination was higher under constant temperatures of 20 and 25ºC, and March was the best seed harvest time for sexual propagation. The commercial substrate was the best for seedling growth, peaking 93.25 percent seedling emergency and 100 percent survival. For asexual propagation, herbaceous cuttings in the commercial substrate and sand presented 96 percent and 95 percent rooting, respectively.