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1.
Ann Bot ; 124(4): 513-520, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31665761

RESUMO

BACKGROUND AND AIMS: Bioenergy crops are central to climate mitigation strategies that utilize biogenic carbon, such as BECCS (bioenergy with carbon capture and storage), alongside the use of biomass for heat, power, liquid fuels and, in the future, biorefining to chemicals. Several promising lignocellulosic crops are emerging that have no food role - fast-growing trees and grasses - but are well suited as bioenergy feedstocks, including Populus, Salix, Arundo, Miscanthus, Panicum and Sorghum. SCOPE: These promising crops remain largely undomesticated and, until recently, have had limited germplasm resources. In order to avoid competition with food crops for land and nature conservation, it is likely that future bioenergy crops will be grown on marginal land that is not needed for food production and is of poor quality and subject to drought stress. Thus, here we define an ideotype for drought tolerance that will enable biomass production to be maintained in the face of moderate drought stress. This includes traits that can readily be measured in wide populations of several hundred unique genotypes for genome-wide association studies, alongside traits that are informative but can only easily be assessed in limited numbers or training populations that may be more suitable for genomic selection. Phenotyping, not genotyping, is now the major bottleneck for progress, since in all lignocellulosic crops studied extensive use has been made of next-generation sequencing such that several thousand markers are now available and populations are emerging that will enable rapid progress for drought-tolerance breeding. The emergence of novel technologies for targeted genotyping by sequencing are particularly welcome. Genome editing has already been demonstrated for Populus and offers significant potential for rapid deployment of drought-tolerant crops through manipulation of ABA receptors, as demonstrated in Arabidopsis, with other gene targets yet to be tested. CONCLUSIONS: Bioenergy is predicted to be the fastest-developing renewable energy over the coming decade and significant investment over the past decade has been made in developing genomic resources and in collecting wild germplasm from within the natural ranges of several tree and grass crops. Harnessing these resources for climate-resilient crops for the future remains a challenge but one that is likely to be successful.


Assuntos
Secas , Árvores , Clima , Produtos Agrícolas , Estudo de Associação Genômica Ampla
2.
Musculoskelet Surg ; 106(4): 371-382, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33982208

RESUMO

BACKGROUND: Although radiographs have been widely used in the evaluation of patients with suspected bone tumors, the lack of an objective radiological assessment method leads to a challenge in reaching correct diagnosis. The study aimed to propose a Radiological Evaluation Score for Bone Tumors (REST) which includes eight radiological factors [characteristics, content, cortical breach, distinctiveness, distribution, periosteal reaction, fracture, and soft tissue swelling] to form a single score along with its validation by multidisciplinary observers. METHODS: We reviewed the radiographs of 100 patients with a primary bone tumor which were selected at random from the database between January 2017 and January 2019 of a tertiary cancer center. Four reviewers (two orthopedic oncologists and two surgical oncologists) independently assessed the radiographs, based on the reporting system of REST. We constituted two groups according to the probable diagnosis of bone tumor (suspected benign tumor and suspected malignant tumor). RESULTS: The mean score in the suspected benign tumor group was 1.1 (range 0-3, 95% CI 0.8-1.3) and in malignant tumor group was 6.1 (range 2-8, 95% CI 5.8-6.4). A receiver operator characteristic (ROC) curve for REST was with a cutoff of 3.5, with the most diagnostic value area under curve (AUC) of 0.99. The sensitivity was 98% and specificity was 100% with a positive predictive value of 100% and a negative predictive value of 98%. The inter-observer correlation coefficient was 0.985 (p value < 0.05), and Fleiss kappa value for the prediction of the benign or malignant lesion was 0.97 (p value < 0.05). The characteristics and content of tumor, cortical erosion, distinctiveness, distribution, periosteal reaction, and soft tissue mass had a significant correlation with the aggressiveness of bone lesion p value < 0.05. CONCLUSIONS: The Radiological Evaluation Score for Bone Tumors (REST) is a structured reporting and objective method for the assessment of radiographs in patients with suspected bone tumors. This method is a reliable and helpful tool for clinicians in their outdoor patient department to differentiate a radiograph of a suspected benign tumor from a malignant bone tumor.


Assuntos
Neoplasias Ósseas , Humanos , Neoplasias Ósseas/diagnóstico , Radiografia , Valor Preditivo dos Testes , Estudos Retrospectivos
3.
Radiography (Lond) ; 27(3): 823-830, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33487526

RESUMO

INTRODUCTION: We propose a ''A to Z RAM (Radiograph Assessment Method)'' for evaluation of Radiograph of patients with a suspected bone tumour. METHODS: In the current study, ten radiological features with letters 'A, B, C, D, E, F and Z' were used and which included the age of the patient, involved part of the bone, characteristics, content, distinctiveness, the exterior of the bone, fracture, and zone of transition. Four independent observers (orthopaedic oncologists and surgical oncologists) evaluated a set of 30 radiographs of bone tumour selected at random from our hospital database based on A to Z RAM. We classified the lesions into two groups according to the traffic signal system; Green (suspected benign lesion) and Red (suspected malignant lesion). RESULTS: There were 18 (60%) benign bone lesions and 12 (40%) malignant lesions in the current study. 91.6% of malignant tumours and 88.8% of the benign tumours were identified correctly by the four observers. The inter-observer variability with Fleiss kappa was 0.884 (95% CI 0.7-1.03 p-value < 0.05), suggestive of agreement not by chance. These radiographs were again reassessed by the four observers after 3 months. The interobserver variability by Fleiss kappa was 1.0 (95% CI 0.8-1.1) suggesting complete agreement amongst the observers. Both orthopaedic oncologists had intra-observer kappa as 1.0 each and both surgical oncologists had 0.795 and 0.930 respectively. CONCLUSION: The proposed A to Z RAM is an easy to use and reproducible method for reviewing radiographs in the out-patient department along with clinical findings for better management of patients with suspected bone lesions. The A to Z RAM can be a medical triage tool and subdivide bone lesions into two subgroups i.e. suspected benign lesion with a suggestion of further investigations with MRI and biopsy and suspected malignant lesion with a suggestion of MRI or early referral to a tertiary cancer center with expertise in orthopaedic oncology. IMPLICATIONS FOR PRACTICE: The A to Z RAM (Radiologic Assessment Method) is a reproducible method for reviewing radiographs in the out-patient department and can be an aid for better management of patients. A to Z RAM is useful as a medical triage system, subdividing patients according to the probable diagnosis into a suspected benign lesion and suspected malignant lesion.


Assuntos
Neoplasias Ósseas , Fraturas Ósseas , Neoplasias Ósseas/diagnóstico por imagem , Humanos , Variações Dependentes do Observador , Radiografia , Triagem
4.
Sci Total Environ ; 654: 841-849, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30448673

RESUMO

Agriculture contributes 18% of India's greenhouse gas (GHG) emissions. Yet, little is known about the energy requirements of individual crops, making it difficult to link nutrition-enhancing dietary changes to energy consumption and climate change. We estimate the energy and CO2 intensity of food grains (rice, wheat, sorghum, maize, pearl millet and finger millet) taking into account their irrigation requirements, water source, dependence on groundwater, yields, fertilizer and machinery inputs. Rice is the most energy-intensive cereal, while millets are the least. Total energy use contributes 16% of GHG emissions for rice, due to its high methane emissions, and 56% for wheat. Fertilizer production and use dominates GHG emissions from all crops, contributing 52% of GHGs from cereals. Energy intensities vary by up to a factor of four across the country, due to varying water requirements, irrigation sources and groundwater table depths. The results suggest that replacing rice with other cereals has the potential to reduce energy consumption and GHGs, though the spatial variation of production shifts would influence the extent of this reduction and the possible trade-offs with total production.


Assuntos
Poluentes Atmosféricos/análise , Produção Agrícola , Grão Comestível/crescimento & desenvolvimento , Gases de Efeito Estufa/análise , Metano/análise , Óxido Nitroso/análise , Irrigação Agrícola , Fertilizantes/análise , Água Subterrânea/análise , Índia
5.
Science ; 360(6385): 212-215, 2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29519919

RESUMO

In temperate and boreal ecosystems, seasonal cycles of growth and dormancy allow perennial plants to adapt to winter conditions. We show, in hybrid aspen trees, that photoperiodic regulation of dormancy is mechanistically distinct from autumnal growth cessation. Dormancy sets in when symplastic intercellular communication through plasmodesmata is blocked by a process dependent on the phytohormone abscisic acid. The communication blockage prevents growth-promoting signals from accessing the meristem. Thus, precocious growth is disallowed during dormancy. The dormant period, which supports robust survival of the aspen tree in winter, is due to loss of access to growth-promoting signals.


Assuntos
Ácido Abscísico/fisiologia , Comunicação Celular/fisiologia , Fotoperíodo , Dormência de Plantas/fisiologia , Reguladores de Crescimento de Plantas/fisiologia , Populus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Ritmo Circadiano , Meristema/citologia , Meristema/crescimento & desenvolvimento , Populus/citologia , Populus/genética , Estações do Ano , Árvores/citologia , Árvores/genética
7.
Gene ; 126(1): 77-83, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7682531

RESUMO

The regulation of the light-harvesting antennae, the phycobilisome (Pbs), and the cpcB1A1-cpcH-cpcI-cpcD operon encoding the structural proteins of the Pbs rod, was studied in the cyanobacterium, Synechococcus sp. PCC 6301, when grown at different light intensities (li). Pbs were purified and their linker protein (LP) profiles analyzed on SDS-polyacrylamide gels. At increasing li, the amount of the distal 30-kDa LP decreased prior to any change in the amount of the proximal 33-kDa LP, indicating a sequential increase in the Pbs rod length. While the amount of LP in the rod decreased with increasing li, the levels of the LP mRNAs increased. Post-transcriptional regulation of the expression of the polycistronic cpcB1A1-cpcH-cpcI-cpcD mRNA was inferred from these observations. The half-life of the mRNAs studied was typically found to be 7 min with four exceptions: (1 and 2) the half-lives for the 3.4- and 3.7-kb polycistronic LP mRNAs were 16 and 1 min at the low (lli) and high li (hli), respectively; (3) the half-life of the 1.4-kb cpcB1A1 mRNA was 2 min at lli; and (4) the 1.3-kb cpcB1A1 transcript had a half-life of 10 min at lli. At hli, it was found that the 1.3-kb cpcB1A1 transcript did not start to disappear until the amount of the 1.4-kb cpcB1A1 transcript had reached the level equal to that of the 1.3-kb mRNA, implying that the 1.4-kb transcript might be processed to the 1.3-kb form.


Assuntos
Proteínas de Bactérias/genética , Cianobactérias/genética , Regulação Bacteriana da Expressão Gênica , Proteínas de Plantas/genética , RNA Mensageiro/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Sequência de Bases , Cianobactérias/metabolismo , DNA Bacteriano , Regulação Bacteriana da Expressão Gênica/efeitos da radiação , Cinética , Luz , Complexos de Proteínas Captadores de Luz , Dados de Sequência Molecular , Peptídeos/metabolismo , Ficobilissomas , Proteínas de Plantas/metabolismo , RNA Bacteriano/genética
8.
Arch Surg ; 116(1): 53-7, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7469733

RESUMO

We studied 32 consecutive cases of small-bowel perforations treated in a single surgical unit during the last three years. Clinical features are typical and diagnosis is not difficult. Suprapubic peritoneal paracentesis in head-high position is the most accurate diagnostic investigation. Ultimate results are not related to cause, but are directly proportional to the degree of contamination of the peritoneal cavity, delay in manifestation, antibiotic resistance of the contaminating organism, and the method of treatment of the perforation. There were two deaths in the 16 patients who had exteriorization of the suture line (12.5%), compared with seven deaths in the group of 16 patients who did not have exteriorization (43.75%). Exteriorization of the suture line (16 cases) is a superior method of treatment and significantly lowers the mortality.


Assuntos
Perfuração Intestinal/cirurgia , Intestino Delgado/cirurgia , Adolescente , Adulto , Resistência Microbiana a Medicamentos , Feminino , Gentamicinas/uso terapêutico , Helmintíase/complicações , Humanos , Perfuração Intestinal/complicações , Perfuração Intestinal/mortalidade , Masculino , Pessoa de Meia-Idade , Peritonite/tratamento farmacológico , Peritonite/etiologia , Sepse/etiologia , Tuberculose Gastrointestinal/complicações
9.
Hepatogastroenterology ; 37(4): 428-31, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2210611

RESUMO

Budd-Chiari syndrome is still a major problem and the overall prognosis for the patients is dismal and disappointing. The case history of a patient with not only outflow obstruction of the hepatic vein but also complete obstruction of the retrohepatic inferior vena cava is presented. She had a patent right inferior hepatic vein which partially decompressed the liver via a rich network of venous collaterals. Management included an inferior vena cava to inferior vena cava shunt using a Goretex graft. The patient fared well and the postoperative course was satisfactory. The case history of this patient illustrates the importance of precise pre-operative investigations for the choice of the type of surgical management. Each patient has to be considered individually on the basis of his or her mechanical peculiarities.


Assuntos
Síndrome de Budd-Chiari/cirurgia , Veias Hepáticas/cirurgia , Adulto , Prótese Vascular , Circulação Colateral/fisiologia , Feminino , Humanos , Politetrafluoretileno , Veia Cava Inferior/cirurgia
10.
Indian J Gastroenterol ; 21(1): 35-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11871838

RESUMO

Embryonal sarcoma of the liver is an unusual tumor. The cystic form is rare and can mimic hydatid disease. We present a case that was mistakenly treated as a hydatid cyst for 3 months. Surgery was successful in removing the mass.


Assuntos
Equinococose Hepática/diagnóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Criança , Erros de Diagnóstico , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Neoplasias Embrionárias de Células Germinativas/cirurgia
11.
Indian J Gastroenterol ; 9(3): 201-4, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2373530

RESUMO

We analyzed our experience in 125 patients with variceal bleeding to compare the efficacy and complications of various schedules of endoscopic variceal sclerotherapy. The schedules for the first three injections were as follows: (A) 3-5 ml of aqueous phenol injected at intervals of three weeks (Group I, n = 28), one week (Group II, n = 30) and three days (Group IIIa, n = 33), and (B) 2-3 ml of phenol at each site at intervals of 3 days (Group IIIb, n = 34). Subsequent injections were given at four week intervals for all groups. Varices could be obliterated significantly earlier (p less than 0.001) in patients injected at 3-day intervals (mean +/- SD 9.12 +/- 5.95 weeks) as compared with those injected at 1-week (13.50 +/- 10.28 weeks) and 3-week (20.55 +/- 7.77 weeks) intervals. The rebleeding rate was not significantly less in the 3-day interval group (Group IIIa--16.66% and Group IIIb--17.64%) as compared with the 1-week (23.3%) and 3-week (28.5%) groups. However the mortality due to rebleed was significantly less (p less than 0.05) in patients injected at 3-day interval (nil), as compared with those injected at 1-week (13.3%) and 3-week (10.7%) intervals. Mucosal ulcerations and stricture formation were observed significantly (p less than 0.001) more frequently in patients undergoing sclerotherapy at 3-day intervals (Group IIIa--51.5% and 18.18%) with 3-5 ml of phenol as compared with those injected similar volume at 1-week (16.66% and 3.3%) and 3-week (7.1% and 3.5%) intervals respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Varizes Esofágicas e Gástricas/terapia , Fenóis/administração & dosagem , Soluções Esclerosantes/administração & dosagem , Adulto , Esquema de Medicação , Endoscopia , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Fenol , Fenóis/uso terapêutico , Soluções Esclerosantes/uso terapêutico
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