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1.
Sci Total Environ ; 901: 165933, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37536603

RESUMO

An essential prerequisite to safeguard pollinator species is characterisation of the multifaceted diversity of crop pollinators and identification of the drivers of pollinator community changes across biogeographical gradients. The extent to which intensive agriculture is associated with the homogenisation of biological communities at large spatial scales remains poorly understood. In this study, we investigated diversity drivers for 644 bee species/morphospecies in 177 commercial apple orchards across 33 countries and four global biogeographical biomes. Our findings reveal significant taxonomic dissimilarity among biogeographical zones. Interestingly, despite this dissimilarity, species from different zones share similar higher-level phylogenetic groups and similar ecological and behavioural traits (i.e. functional traits), likely due to habitat filtering caused by perennial monoculture systems managed intensively for crop production. Honey bee species dominated orchard communities, while other managed/manageable and wild species were collected in lower numbers. Moreover, the presence of herbaceous, uncultivated open areas and organic management practices were associated with increased wild bee diversity. Overall, our study sheds light on the importance of large-scale analyses contributing to the emerging fields of functional and phylogenetic diversity, which can be related to ecosystem function to promote biodiversity as a key asset in agroecosystems in the face of global change pressures.

2.
Waste Manag ; 119: 11-21, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33032154

RESUMO

This study investigated the possibility to use thermophilic anaerobic high solid digestion of dewatered digested sewage sludge (DDS) at a wastewater treatment plant (WWTP) as a measure to increase total methane yield, achieve pasteurization and reduce risk for methane emissions during storage of the digestate. A pilot-scale plug-flow reactor was used to mimic thermophilic post-treatment of DDS from a WWTP in Linköping, Sweden. Process operation was evaluated with respect to biogas process performance, using both chemical and microbiological parameters. Initially, the process showed disturbance, with low methane yields and high volatile fatty acid (VFA) accumulation. However, after initiation of digestate recirculation performance improved and the specific methane production reached 46 mL CH4/g VS. Plug flow conditions were assessed with lithium chloride and the hydraulic retention time (HRT) was determined to be 19-29 days, sufficient to reach successful pasteurization. Degradation rate of raw protein was high and resulted in ammonia-nitrogen levels of up to 2.0 g/L and a 30% lower protein content in the digestate as compared to DDS. Microbial analysis suggested a shift in the methane producing pathway, with dominance of syntrophic acetate oxidation and the candidate methanogen family WSA2 by the end of the experiment. Energy balance calculations based on annual DDS production of 10000 ton/year showed that introduction of high-solid digestion as a post-treatment and pasteurization method would result in a positive energy output of 340 MWh/year. Post-digestion of DDS also decreased residual methane potential (RMP) by>96% compared with fresh DDS.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Digestão , Metano/análise , Pasteurização , Suécia
3.
Mol Ecol ; 20(22): 4808-21, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21980996

RESUMO

Legume plants can obtain combined nitrogen for their growth in an efficient way through symbiosis with specific bacteria. The symbiosis between Rhizobium galegae and its host plant Galega is an interesting case where the plant species G. orientalis and G. officinalis form effective, nitrogen-fixing, symbioses only with the appropriate rhizobial counterpart, R. galegae bv. orientalis and R. galegae bv. officinalis, respectively. The symbiotic properties of nitrogen-fixing rhizobia are well studied, but more information is needed on the properties of the host plants. The Caucasus region in Eurasia has been identified as the gene centre (centre of origin) of G. orientalis, although both G. orientalis and G. officinalis can be found in this region. In this study, the diversity of these two Galega species in Caucasus was investigated to test the hypothesis that in this region G. orientalis is more diverse than G. officinalis. The amplified fragment length polymorphism fingerprinting performed here showed that the populations of G. orientalis and R. galegae bv. orientalis are more diverse than those of G. officinalis and R. galegae bv. officinalis, respectively. These results support the centre of origin status of Caucasus for G. orientalis at a genetic level. Analysis of the symbiosis-related plant genes NORK and Nfr5 reveals remarkable diversity within the Nfr5 sequence, although no evidence of adaptive evolution could be found.


Assuntos
Galega/genética , Variação Genética , Genoma de Planta , Filogenia , Simbiose/genética , Sequência de Aminoácidos , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , DNA de Plantas/genética , Galega/microbiologia , Dados de Sequência Molecular , Rhizobium/fisiologia , Federação Russa , Análise de Sequência de DNA
4.
Gen Hosp Psychiatry ; 23(4): 198-204, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11543846

RESUMO

Failure of general anesthesia to render a patient insensate, termed "awareness," is estimated to affect between 40,000 and 140,000 patients in the US each year. This study investigated the occurrence of post-traumatic stress disorder (PTSD) in subjects who reported a past episode of intraoperative awareness. We inquired about intraoperative and postoperative experiences and studied the relationship between various surgical experiences and currently meeting the diagnosis of PTSD. Sixteen postawareness subjects and 10 postgeneral anesthesia controls completed the Clinician Administered PTSD Scale (CAPS), a standardized clinical rating scale for PTSD, and a questionnaire about peri-operative experiences. Nine of 16 subjects (56.3%), a mean of 17.9 postoperative years, and no controls met diagnostic criteria for current PTSD (X(2)= 8.6, df = 1, P<.01). Common intraoperative experiences included an inability to communicate, helplessness, terror, and pain. Postawareness patients had significant postoperative distress related to feeling unable to communicate, unsafe, terrified, abandoned and betrayed. Perioperative dissociative experiences predicted having current PTSD. Being conscious during surgery is a traumatic event that may result in developing chronic PTSD. Further studies should include prospective designs of prevalence and long-term psychological, social, and overall health effects, and ways of preventing and treating awareness-induced PTSD.


Assuntos
Anestesia Geral/efeitos adversos , Conscientização , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Adulto , Doença Crônica , Transtornos Dissociativos/diagnóstico , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Inquéritos e Questionários
7.
Surv Ophthalmol ; 43(3): 233-44, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9862311

RESUMO

Understanding the effect of serum lipid levels on risk factors for coronary heart disease and how they are influenced by medical therapy may lead to overall better care of the glaucoma patient. Elevated low-density lipoprotein and total cholesterol levels are major risk factors for heart disease. In contrast, high-density lipoprotein (HDL) is protective for heart disease. beta-adrenergic blockers, a class of medicines used to treat glaucoma, may influence serum lipid levels. Oral nonselective beta-adrenergic blockers reduce HDL cholesterol by 19% and increase triglycerides by 20-40%. Furthermore, topical nonselective beta-adrenergic blockers also decrease serum HDL and worsen the total cholesterol/HDL ratio. However, beta-blockers with intrinsic sympathomimetic activity appear to be lipid neutral. At present, there is no clear clinical evidence to indicate that changes in serum lipids with use of topical beta-adrenergic blockers significantly affect the clinical course of the patient. Little information is available for other classes of medicines used topically to treat glaucoma. However, oral preparations of prostaglandins, alpha-adrenergic agonists, angiotensin-converting enzyme inhibitors, and calcium channel blockers do not adversely affect serum lipid levels. Further study is required on newer glaucoma preparations to determine their specific actions on lipid levels. Additionally, further work is required to understand the significance of not only the adverse effect of beta-adrenergic blockers on lipid levels, but their overall effect on long-term cardiac morbidity and mortality.


Assuntos
Glaucoma de Ângulo Aberto/tratamento farmacológico , Lipídeos/sangue , Antagonistas Adrenérgicos beta/efeitos adversos , Antagonistas Adrenérgicos beta/uso terapêutico , Doença das Coronárias/sangue , Doença das Coronárias/induzido quimicamente , Glaucoma de Ângulo Aberto/sangue , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/induzido quimicamente , Fatores de Risco
8.
Gen Hosp Psychiatry ; 20(5): 274-81, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9788027

RESUMO

It has been estimated that approximately 30,000 patients a year suffer awareness or consciousness during anesthesia. This paper reviews existing knowledge of the psychological impact and psychiatric sequelae of awareness during anesthesia. Literature on awareness and memory during anesthesia, traumatic memory, and posttraumatic stress disorder (PTSD) was reviewed using computer searches, books, and referenced articles. Few case reports of awareness have identified the accompanying psychological trauma and resulting PTSD. Five published cases illustrating relevant material were selected for inclusion. Waking up during anesthesia, especially if the patient experienced pain, is a traumatic event which places the patient at risk for developing PTSD. Awareness-induced PTSD must be considered for patients who present for mental health treatment following surgery. The advantages of light anesthesia must be balanced against the risk of awareness-induced PTSD.


Assuntos
Anestesia Geral/psicologia , Conscientização , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Humanos , Rememoração Mental , Dor/psicologia , Fatores de Risco
9.
Gene ; 211(2): 187-94, 1998 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-9602122

RESUMO

Rabbit eIF2C (94kDa) has been shown to play important roles in the eukaryotic peptide chain initiation process. In this study, the primary structure of rabbit eIF2C is determined by cDNA cloning. Based on the partial amino acid sequences of Endolys C cleaved fragments, degenerate oligonucleotides were synthesized and used as primers for the polymerase chain reaction to amplify the corresponding cDNA fragment from a rabbit liver cDNA library. This fragment was subsequently used to screen for larger cDNAs. Marathon cDNA amplification and 5'-rapid amplification of cDNA ends were used to confirm the translation start site. Sequences from the overlapping clones were assembled into a 3599-bp composite sequence, which contains a single open reading frame that translates into a 813-deduced amino acid sequence. Northern blot analysis of rabbit liver ploy(A)+ RNA yielded a single message species at approximately 4.6kb. Western blot analysis of rabbit reticulocyte lysate using polyclonal antibody against the 94kDa eIF2C detected a higher-molecular-weight polypeptide (140kDa). No 94kDa polypeptide was detected. The cloned cDNA was further characterized by in-vitro transcription-coupled translation in reticulocyte lysate. The translated product was precipitated with antibodies against eIF2C. Genomic Southern blot analysis indicates that the rabbit eIF2C is a single copy gene. Sequence analysis reveals that rabbit eIF2C has strong homology with a hypothetical protein in Caenorhabditis elegans.


Assuntos
Fatores de Iniciação de Peptídeos/genética , Proteínas/química , Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Southern Blotting , Sistema Livre de Células , Clonagem Molecular , DNA/análise , DNA/genética , DNA Complementar/análise , DNA Complementar/química , DNA Complementar/genética , Genes/genética , Genoma , Fatores de Troca do Nucleotídeo Guanina , Dados de Sequência Molecular , Peso Molecular , Fatores de Iniciação de Peptídeos/análise , Fatores de Iniciação de Peptídeos/química , Biossíntese de Proteínas/genética , RNA Mensageiro/análise , Coelhos , Análise de Sequência de DNA
10.
Genetics ; 146(3): 1131-41, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9215914

RESUMO

This article reports the cloning of the genes encoding the Arabidopsis and rice class III ADH enzymes, members of the alcohol dehydrogenase or medium chain reductase/dehydrogenase superfamily of proteins with glutathione-dependent formaldehyde dehydrogenase activity (GSH-FDH). Both genes contain eight introns in exactly the same positions, and these positions are conserved in plant ethanol-active Adh genes (class P). These data provide further evidence that plant class P genes have evolved from class III genes by gene duplication and acquisition of new substrate specificities. The position of introns and similarities in the nucleic acid and amino acid sequences of the different classes of ADH enzymes in plants and humans suggest that plant and animal class III enzymes diverged before they duplicated to give rise to plant and animal ethanol-active ADH enzymes. Plant class P ADH enzymes have gained substrate specificities and evolved promoters with different expression properties, in keeping with their metabolic function as part of the alcohol fermentation pathway.


Assuntos
Aldeído Oxirredutases/genética , Arabidopsis/enzimologia , Oryza/enzimologia , Álcool Desidrogenase/genética , Aldeído Oxirredutases/metabolismo , Aldeído Oxirredutases/fisiologia , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Sequência de Bases , Clonagem Molecular , DNA de Plantas , Evolução Molecular , Humanos , Íntrons , Dados de Sequência Molecular , Oryza/genética , Filogenia
11.
J Biol Chem ; 272(19): 12692-8, 1997 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-9139726

RESUMO

A rat genomic library constructed in lambda-EMBL3 (SP6/T7) vector () was screened using 32P-labeled rat p67 cDNA. A clone containing a segment of 5'-upstream region of p67 genomic DNA was obtained. The DNA (about 1.7 kilobase pairs) was isolated and characterized. Sequence analysis of this DNA fragment showed that the 898 base pairs at the 5'-end of the upstream region was identical to several long interspersed nucleotide sequences. One hundred forty-eight base pairs at the 3'-end contained the beginning of the first exon including the ATG initiator codon. The remaining 652 base pairs in between contained two AT-rich regions and several regulatory sequences. The mRNA initiation site was identified at 89 base pairs upstream from the translation start codon. The DNA fragment was also analyzed by transient transfection. When linked to a firefly luciferase reporter gene, this fragment enhanced transcription in a rat hepatoma cell line (KRC-7). Using a series of deletions in the DNA, the minimum essential promoter region (from -177 to -60) was identified. The promoter activity was also enhanced by treatment with phorbol 13-myristate 12-acetate (PMA). This enhancement required an AP-1 sequence (-298 to -292; 5'-TGACTCA-3') and a similar sequence (-97 to -88; 5'-ATGACATCAT-3'). Deletion of either of these sequences significantly reduced PMA enhancement. Deletion of both of these sequences almost completely eliminated PMA enhancement.


Assuntos
Aminopeptidases , Glicoproteínas/genética , Regiões Promotoras Genéticas , Animais , Sequência de Bases , Carcinógenos/farmacologia , Clonagem Molecular , Neoplasias Hepáticas Experimentais/química , Dados de Sequência Molecular , Ratos , Deleção de Sequência , Acetato de Tetradecanoilforbol/farmacologia , Transfecção
13.
CMAJ ; 152(7): 1051-5, 1995 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-7712416

RESUMO

Universal precautions have gained wide acceptance in the literature and are promoted by major health care regulatory bodies as a measure to prevent nosocomial transmission of bloodborne diseases. Nevertheless, Dr. James G. Wright and associates (see pages 1089 to 1095 of this issue) provide evidence of the infrequent use of universal precautions by surgeons in Toronto. Their findings are consistent with those of similar studies and point to the limitations of any safety approach that relies on the active compliance of individuals rather than on passive, environmental controls. Successful approaches to optimizing workplace safety should first emphasize passive measures for risk abatement, including firm policies, the use of safer equipment and techniques, procedural safeguards and regular monitoring. Routine voluntary screening of patients undergoing procedures that pose a high risk of contamination may improve compliance to safety procedures by health care personnel. Further study is required.


Assuntos
Atitude do Pessoal de Saúde , Saúde Ocupacional , Precauções Universais , Humanos , Política Organizacional , Precauções Universais/métodos , Precauções Universais/estatística & dados numéricos
14.
Res Virol ; 146(2): 93-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7638441

RESUMO

We describe nucleotide sequences of human T-lymphotropic virus type I (HTLV-I) proviruses from three symptomatic family members with tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) from Tumaco, Colombia. Polymerase chain reaction was used to clone the U3 region, envelope and tax/rex genes of these HTLV-I proviruses from fresh peripheral blood lymphocytes. Sequences in U3, env and tax/rex showed 96.9-99.5% conservation when compared with sequences from HTLV-I clone ATK, and 96.6-100% when compared with each other. The range of sequence divergence within the family was similar to that described between unrelated TSP/HAM patients of the same geographical origin. Certain mutations were present in all three family members, supporting a geographic and/or familial segregation of mutations.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Paraparesia Espástica Tropical/virologia , Adulto , Sequência de Aminoácidos , Sequência de Bases , Análise Mutacional de DNA , DNA Viral/análise , Éxons , Feminino , Genes Virais , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Paraparesia Espástica Tropical/sangue , Provírus/genética , Ribonucleoproteínas Nucleares Pequenas/genética
15.
Gene Expr ; 5(2): 113-22, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8821624

RESUMO

The p67 mRNA level and p67 requirement in protein synthesis were studied using an animal cell (KRC-7, rat tumor hepatoma cell) in culture. p67 mRNA was present in confluent cells but disappeared almost completely from serum-starved cells. However, when PMA was added to the serum-starved cells, p67 mRNA appeared in increasing quantities. Several-fold molar excess of p67 mRNA over that present in confluent cells was detected within 2 h of PMA addition and this level remained the same during the 4 h of the experiment. p67 requirement in protein synthesis was studied using a p67 antisense DNA construct under a metallothionein gene promoter. Expression of this antisense DNA in the presence of zinc in PMA-induced serum-starved cells completely inhibited induced appearance of p67 mRNA and subsequent protein synthesis. These results suggest that p67 is regulated at the mRNA level and also that this protein factor is essential for protein synthesis.


Assuntos
Aminopeptidases , Fator de Iniciação 2 em Eucariotos/metabolismo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Biossíntese de Proteínas , Animais , Linhagem Celular , DNA Antissenso/genética , Immunoblotting , Cinética , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Acetato de Tetradecanoilforbol/farmacologia , Transformação Genética , Regulação para Cima
16.
Photosynth Res ; 46(3): 467-72, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24301641

RESUMO

Use of leaf meters to provide an instantaneous assessment of leaf chlorophyll has become common, but calibration of meter output into direct units of leaf chlorophyll concentration has been difficult and an understanding of the relationship between these two parameters has remained elusive. We examined the correlation of soybean (Glycine max) and maize (Zea mays L.) leaf chlorophyll concentration, as measured by organic extraction and spectrophotometric analysis, with output (M) of the Minolta SPAD-502 leaf chlorophyll meter. The relationship is non-linear and can be described by the equation chlorophyll (µmol m(-2))=10((M0.265)), r (2)=0.94. Use of such an exponential equation is theoretically justified and forces a more appropriate fit to a limited data set than polynomial equations. The exact relationship will vary from meter to meter, but will be similar and can be readily determined by empirical methods. The ability to rapidly determine leaf chlorophyll concentrations by use of the calibration method reported herein should be useful in studies on photosynthesis and crop physiology.

17.
Photosynth Res ; 44(1-2): 107-15, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-24307030

RESUMO

The study of the light-harvesting complex II (LHC-II) phosphatase activity has been difficult due to the membrane association of its substrate. Thylakoid membranes labeled with [γ-(32)P]ATP were incubated with chymotrypsin, releasing phosphopeptides which served as labeled substrates for LHC-II phosphatase. Utilizing these phosphopeptides as substrates, protein phosphatase activities have been identified in both the thylakoid membrane and the stromal fraction. The thylakoid-bound phosphatase was liberated from the membrane with a sub-solubilizing concentration of Brij 35. The membrane and the stromal protein phosphatases were inhibited by NaF and EDTA, but not inhibited by microcystin-LR. The stromal phosphatase differed from the membrane phosphatase in pH optimum, in its lack of inhibition by molybdate ions, and by its response to magnesium and manganese ions. Using the soluble chymotryptic peptide substrate, the effect of light on pea thylakoid-bound LHC-II phosphatase activity was also assessed. Incubation of the thylakoid membranes in the light caused a 35% inhibition of LHC-II phosphatase activity. The inhibition was diminished by the addition of DCMU. Addition of 10 mM dithiothreitol stimulated the activity in darkness and obviated the inhibition when exposed to light. These studies suggest that positive or negative regulation of the LHC-II phosphatase activity is possible in vivo.

20.
Biochem Genet ; 31(11-12): 497-506, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8166623

RESUMO

The homodimeric alcohol dehydrogenase gene produce of maize (Zea mays L.) Adh1-1S1108 mutation was purified and compared with the parental Adh1-1S enzyme. The mutant alcohol dehydrogenase activity had pH optima and substrate specificity similar to those of the parental enzyme, but exhibited somewhat increased and decreased Km values for acetaldehyde and NADH, respectively. The mutant enzyme was also markedly less stable than the enzyme from parental tissues to temperatures as low as 50 degrees C. Sequence analysis of a polymerase chain reaction (PCR)-generated cDNA clone revealed a G-to-C mutation at position 406 and a C-to-T mutation at position 974. These would result in residue 103 of each protein subunit being changed from an alanine to a proline and residue 292 being changed from an alanine to a valine. Whether one or both of these changes in primary sequence is responsible for the altered substrate affinities and stability is not yet understood.


Assuntos
Álcool Desidrogenase/genética , Proteínas de Plantas/genética , Zea mays/genética , Álcool Desidrogenase/metabolismo , Álcoois/metabolismo , Alelos , Sequência de Aminoácidos , Grão Comestível/enzimologia , Grão Comestível/genética , Genes de Plantas , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Especificidade por Substrato , Zea mays/enzimologia
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