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81.
Tiago Natal-da-Luz Serena Tidona Bruno Jesus Paula V. Morais José P. Sousa 《Journal of Soils and Sediments》2009,9(3):246-260
Background, aim, and scope Sewage sludge use in agriculture should be limited by the presence of metals and other persistent environmental pollutants.
The present study aims to contribute for the definition of a test battery of ecotoxicological assays that allows a proper
ecotoxicological characterization of sludges, providing information on their potential hazard and identified “safe” application
levels.
Materials and methods Three sludges from distinct sources (urban, olive-processing, and electroplating industries) were tested using avoidance and
reproduction tests with earthworms (Eisenia andrei) and springtails (Folsomia candida) and plant growth tests with turnips (Brassica rapa) and oats (Avena sativa). Different soil–sludge mixture concentrations mimicking recommended/realistic field dosages were tested.
Results Only the sludge from the electroplating industry induced an avoidance response from the earthworms (EC50 = 0.4 t/ha) and collembolans (no observed effect concentration (NOEC) = 15 t/ha). This sludge was the only sludge responsible
for any effect on the reproductive output of the earthworms (EC50 = 7.74 t/ha). Regarding collembolans, none of the sludges tested caused any significant decrease in reproduction. In higher
plant tests, the two industrial sludges were toxic, causing a decrease growth in both species. The EC20 values determined for B. rapa were 20.3 and 24.2 t/ha and for A. sativa 14.7 and 16.2 t/ha for sludges from olive-processing and electroplating industries, respectively.
Discussion The metal loadings of the different test sludges could partially explain the results obtained. The toxicity of the test sludge
from electroplating industry observed on the tested invertebrates and plants could be explained by the high amount of total
chromium from which 22.3% was in the most toxic oxidation state—Cr(VI). However, the toxicity caused by the sludge from the
olive-processing industry in the test plants could be attributed to the presence of other compounds (not measured in this
study) since the metal content was not high enough to induce such an effect. The absence of toxicity showed by the urban test
sludge was in agreement with its low levels of metals.
Conclusions The response of the different test organisms and end points varied according to the sludge type. The urban sludge was non-toxic
whereas the sludge from the electroplating industry caused a toxic effect on almost all parameters measured (avoidance behavior
of both test organisms, reproduction of earthworms, and growth of both plant species). Sludge from the olive-processing industry
only caused a toxic effect on growth of both plant species. By analyzing the sensitivity of the different parameters for the
most toxic sludge, it was found that avoidance and reproduction were more sensitive than plant growth, whereas plant seed
germination was not sensitive at all.
Recommendations and perspectives The ecotoxicological evaluation of wastes can be used as an environmental safety control of sludge use in agriculture. A tiered
approach could be adopted for this purpose, incorporating avoidance tests in the first tier (screening level) and reproduction
and plant growth tests in a second tier. But more evidence aiming to define the most suitable ecotoxicological test battery
for specific sludges with a different contamination profile is still needed. 相似文献
82.
Iñiguez AM Carvalho VL Motta MR Pinheiro DC Vicente AC 《Veterinary parasitology》2011,175(3-4):293-299
Prevalence and seasonal variations of helminth infections and their association with morbidity parameters were studied in traditionally reared Cambodian cattle. Four villages in two provinces of West Cambodia were visited on monthly intervals over a period of 11 months, during which 2391 animals were faecal and blood sampled for parasitological and haematological examinations. The body condition score (BCS), faecal consistency (diarrhoea score, DS), colour of the ocular conjunctivae (FAMACHA(?)) and packed cell volume were determined for each individual animal. The overall proportion of samples that was positive for gastrointestinal nematodes was 52%, 44% and 37% in calves (from 1 to 6 months), young animals (6 to 24 months) and adults (over 24 months), respectively, while geometric mean faecal egg counts (FECs) for each of these age categories were 125, 66 and 15 eggs per gram, respectively. Six genera of strongyles were found in the faecal cultures, i.e. in descending order of occurrence, Cooperia, Oesophagostomum, Haemonchus, Trichostrongylus, Mecistocirrus and Bunostomum. The prevalences of Fasciola and Paramphistomum, estimated by coprological examination, varied between 5-20% and 45-95%, respectively. Logistic mixed models were used to investigate associations of morbidity markers with the presence of parasite infection. A low BCS was associated with gastrointestinal nematode and liver fluke infections, and soft faecal consistency with Paramphistomum infections. However, other factors such as nutritional deficiencies and intercurrent diseases are likely to enhance the effects of parasites and should therefore be considered when using these morbidity parameters as indicators of parasitism. 相似文献
83.
de Oliveira Wildiney Freire de Lima Elizanne Moura de Freitas Denise Ribeiro dos Santos Suely Sousa Reis Grazielle Carvalho Gomes Daiany Iris Alves Kaliandra Souza Maciel Raylon Pereira Vargas Julián Andrés Castillo Mezzomo Rafael 《Tropical animal health and production》2020,52(5):2379-2385
Tropical Animal Health and Production - We aimed to evaluate the chemical composition, production yield, and economic viability of Minas Frescal cheese produced with milk from buffaloes... 相似文献
84.
de Medeiros Erika Valente Lima Neyla Thayná de Sousa Lima José Romualdo Pinto Kedma Maria Silva da Costa Diogo Paes Franco Junior Cícero Luiz Souza Rodolfo Marcondes Silva Hammecker Claude 《Phytoparasitica》2021,49(4):713-726
Phytoparasitica - The current agricultural scenario faces a range of challenges, with phytosanitary ones being paramount. In most cases, plant diseases are treated with chemicals; however, they... 相似文献
85.
A. Sotelo H. Sousa M. Sánchez 《Plant foods for human nutrition (Dordrecht, Netherlands)》1995,47(2):93-100
Five wildPhaseolus vulgaris beans were compared with five cultivatedPhaseolus vulgaris beans in proximate composition, total (true) protein, amino acid composition, and toxic and antinutritional factors. The wild beans contained more protein (25.5% vs. 21.7%), ash (5.15 vs. 4.15%), crude fiber (7.08% vs. 5.04%) compared to cultivated beans while the former contained less fat (0.56 vs. 0.89%) and carbohydrates (61.64 vs. 68.05%). Sulfur amino acids were found to be limiting in both groups of bean as expected; however, the cultivated beans had a higher content of the limiting amino acids. Therefore, the cultivated beans showed a better amino acid profile than the wild beans. Toxic factors were not found in either type of bean; the determinations included saponins, alkaloids, and cyanogenic glycosides. The antinutritional factors investigated were hemagglutinins (lectins) and trypsin inhibitors. The wild beans presented a higher content of trypsin inhibitors (28 TUI per mg) and lectins (9.6) than the cultivated beans did (21 TUI per mg and 7 respectively). From the chemical point of view, domestication seems to be positive; however, the better protein nutritive quality of the cultivated beans should be further confirmed by biological assays. 相似文献
86.
Stefano Nones Camila Fernandes Lídia Duarte Leonor Cruz Edmundo Sousa 《Plant pathology》2022,71(4):966-979
In Portugal, the oak pinhole borer Platypus cylindrus and its mycobiota have been associated with cork oak (Quercus suber) death, but no knowledge exists regarding the associated bacterial community. However, it is known that some bacteria are important for ambrosia beetle symbiosis and play a role in oak tree health. To explore the bacteria associated with this beetle and its host, with the ultimate goal of highlighting potential roles in oak decline, this study used a culture-dependent approach for strain isolation and phylogenetic identification using 16S rRNA gene sequencing and multilocus sequence analysis (MLSA). The bored galleries of different cork oak trees from a cork stand in Alentejo, together with the body and mycangia of adult beetles, were investigated. The samples revealed a diverse community comprising 500 isolates with 64 distinct types of bacterial colonies. Sixty-eight strains were selected for sequencing and used for phylogenetic analysis, 40 from wood galleries and 28 from beetles. Thirty-two genera of bacteria were identified, 18 of which were described for the first time within oak–beetle interactions. Major taxonomic groups were Actinobacteria in beetles and Enterobacterales in wood galleries. Although specific oak bacterial pathogens were not detected, a group of distinct strains detected in wood galleries, potentially belonging to a new Pectobacteriaceae species, were able to produce mild symptoms on cork oak plantlets. This study reports for the first time the biodiversity of culturable bacteria associated with the Q. suber–P. cylindrus interaction, their relevance to both organisms and the possible contribution to oak decline. 相似文献
87.
Ana Maria Athayde Uchoa José Maria Correia da Costa Geraldo Arraes Maia Tatyane Ribeiro Meira Paulo Henrrique Machado Sousa Isabella Montenegro Brasil 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):153-159
Cashew apple and guava residues from fruit juice industry were prepared as dehydrated fruit powders and used at different
levels of wheat flour substitution for cookies formulations. The effects of guava and cashew apple fruit powders supplementation
on physicochemical and sensorial characteristics of the cookies were evaluated. The pH, fibre and protein content were significantly
affected. Biscuits with 15 g and 20 g/100g cashew apple and guava fruit powders showed the highest scores for sensorial attributes,
respectively. The supplementation seems to be suited for wheat flour substitution and it is possible to obtain cookies with
value-added food ingredient within the standards. 相似文献
88.
Oceans are a rich source of structurally unique bioactive compounds from the perspective of potential therapeutic agents. Marine peptides are a particularly interesting group of secondary metabolites because of their chemistry and wide range of biological activities. Among them, cyclic peptides exhibit a broad spectrum of antimicrobial activities, including against bacteria, protozoa, fungi, and viruses. Moreover, there are several examples of marine cyclic peptides revealing interesting antimicrobial activities against numerous drug-resistant bacteria and fungi, making these compounds a very promising resource in the search for novel antimicrobial agents to revert multidrug-resistance. This review summarizes 174 marine cyclic peptides with antibacterial, antifungal, antiparasitic, or antiviral properties. These natural products were categorized according to their sources—sponges, mollusks, crustaceans, crabs, marine bacteria, and fungi—and chemical structure—cyclic peptides and depsipeptides. The antimicrobial activities, including against drug-resistant microorganisms, unusual structural characteristics, and hits more advanced in (pre)clinical studies, are highlighted. Nocathiacins I–III (91–93), unnarmicins A (114) and C (115), sclerotides A (160) and B (161), and plitidepsin (174) can be highlighted considering not only their high antimicrobial potency in vitro, but also for their promising in vivo results. Marine cyclic peptides are also interesting models for molecular modifications and/or total synthesis to obtain more potent compounds, with improved properties and in higher quantity. Solid-phase Fmoc- and Boc-protection chemistry is the major synthetic strategy to obtain marine cyclic peptides with antimicrobial properties, and key examples are presented guiding microbiologist and medicinal chemists to the discovery of new antimicrobial drug candidates from marine sources. 相似文献
89.
Brenna de Sousa Barbosa Herlon Victor Rodrigues Silva Beatriz Evaristo de Almeida Tabosa Thalles Gothardo Pereira Nunes Francisco Felipe de Magalhes Lúcia Daniel Machado da Silva 《Reproduction in domestic animals》2019,54(12):1630-1636
Sperm morphometry is the tool that confers objectivity to the morphological evaluation by accurately measuring the dimensions of the gamete and its structures. Thus, the aim of the study was to perform a morphometric characterization of the domestic cat sperm. Therefore, sperm samples were collected from twenty pairs of epididymis in a TRIS extender at 37ºC. An aliquot of the sample was used to make a smear with Rose Bengal solution, and afterwards, the morphology and morphometry were analysed. In the morphology, were quantified the percentage of normal sperm cells, morphological changes of head, midpiece and tail. In morphometry, each normal sperm cell was measured for length, width, area and perimeter of head and midpiece, tail length and total length. The parameters ellipticity, elongation, regularity and rugosity were also determined. The percentage of normal sperm was 67.21%. Of the abnormalities, the curled/folded tail, followed by the curved midpiece, abnormal shaped head and detached head were the most quantified. The sperm head presented 5.56 ± 0.01 μm and 3.10 ± 0.01 μm of length and width, respectively. The head area was 16.94 ± 0.05 μm2, while the perimeter was 16.16 ± 0.03 μm. In the derived parameters, the values were as follows: ellipticity of 1.81 ± 0.00; elongation of 21.39 ± 0.12; regularity of 0.81 ± 0.00; and rugosity of 0.14 ± 0.00. The midpiece presented length and width of 7.96 ± 0.01 μm and 0.76 ± 0.01 μm, respectively. The mean length of the sperm tail was 45.12 ± 0.06 μm, and the total cell size was 58.67 ± 0.06 μm. Thus, it was concluded that the cat sperm is an elongated cell, with high rugosity and regularity. The spermatic tail represents more than ¾ of the total length of the cell and the midpiece exceeds the length of the head. 相似文献
90.
A. M. Becker DVM T. A. Janik DVM E. K. Smith DVM C. A. Sousa DVM B. A. Peters PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1989,3(1):26-30
In a randomized, double-blind, placebo-controlled study, dogs with chronic recurrent pyoderma were treated with antibiotics plus intravenous injections of either Propionibacterium acnes or placebo. Responses (an increase, decrease, or clearing of lesions) were measured and evaluated statistically. Eighty percent (12 of 15) of the dogs treated with antibiotics and P acnes compared with 38% (five of 13) of the dogs treated with antibiotics and placebo responded with significant improvement or complete remission of lesions at the end of the 12-week treatment schedule (P less than 0.05). 相似文献