Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
Eur J Med Res ; 28(1): 318, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660038

RESUMO

BACKGROUND: An effective testing strategy is essential for pandemic control of the novel Coronavirus disease 2019 (COVID-19) caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Breath gas analysis can expand the available toolbox for diagnostic tests by using a rapid, cost-beneficial, high-throughput point-of-care test. We conducted a bi-center clinical pilot study in Germany to evaluate breath gas analysis using multi-capillary column ion mobility spectrometry (MCC-IMS) to detect SARS-CoV-2 infection. METHODS: Between September 23, 2020, and June 11, 2021, breath gas measurements were performed on 380 patients (SARS-CoV-2 real-time polymerase chain reaction (PCR) positive: 186; PCR negative: 194) presenting to the emergency department (ED) with respiratory symptoms. RESULTS: Breath gas analysis using MCC-IMS identified 110 peaks; 54 showed statistically significant differences in peak intensity between the SARS-CoV-2 PCR-negative and PCR-positive groups. A decision tree analysis classification resulted in a sensitivity of 83% and specificity of 86%, but limited robustness to dataset changes. Modest values for the sensitivity (74%) and specificity (52%) were obtained using linear discriminant analysis. A systematic search for peaks led to a sensitivity of 77% and specificity of 67%; however, validation by transferability to other data is questionable. CONCLUSIONS: Despite identifying several peaks by MCC-IMS with significant differences in peak intensity between PCR-negative and PCR-positive samples, finding a classification system that allows reliable differentiation between the two groups proved to be difficult. However, with some modifications to the setup, breath gas analysis using MCC-IMS may be a useful diagnostic toolbox for SARS-CoV-2 infection. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov on September 21, 2020 (NCT04556318; Study-ID: HC-N-H-2004).


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , SARS-CoV-2 , Projetos Piloto , Espectrometria de Mobilidade Iônica
2.
Oncogene ; 37(3): 302-312, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28925403

RESUMO

Melanoma is a heterogeneous tumor with different subpopulations showing different proliferation rates. Slow-cycling cells were previously identified in melanoma, but not fully biologically characterized. Using the label-retention method, we identified a subpopulation of slow-cycling cells, defined as label-retaining cells (LRC), with strong invasive properties. We demonstrate through live imaging that LRC are leaving the primary tumor mass at a very early stage and disseminate to peripheral organs. Through global proteome analyses, we identified the secreted protein SerpinE2/protease nexin-1 as causative for the highly invasive potential of LRC in melanomas.


Assuntos
Ciclo Celular , Melanoma/patologia , Serpina E2/metabolismo , Neoplasias Cutâneas/patologia , Animais , Linhagem Celular Tumoral , Separação Celular/métodos , Citometria de Fluxo/métodos , Humanos , Melanócitos/metabolismo , Melanócitos/patologia , Camundongos , Invasividade Neoplásica/patologia , Proteômica , Pele/citologia , Pele/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Gesundheitswesen ; 80(7): 621-627, 2018 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-27611882

RESUMO

OBJECTIVES: The number of patients visiting emergency departments (ED) is steadily increasing. The cause for this rise in Germany is unclear and less examined. This study aimed to assess the reasons of walk-in patients to visit EDs by using a direct survey. METHODS: During a period of 4 weeks, 2 010 walk-in patients were anonymously surveyed in 2 major Berlin hospitals using a standardized questionnaire. Descriptive statistics were used for data analysis. RESULTS: More than 90% of patients assessed themselves as an emergency and three-quarters of patients reported pain. The majority of patients (57%) tried to contact statutory health insurance (SHI) office-based physicians in advance and 59% of patients said they would make use of ambulatory emergency facilities if they were available and well established. However, 55% of patients were unaware of the emergency service of the association of SHI physicians. CONCLUSION: The results indicate that centralized ambulatory emergency facilities should be available 24/7 at hospitals with EDs. Therefore, future planning of emergency services should integrate providers of ambulatory and inpatient sector. International experience suggests that different instruments aiming at better coordination of care, such as integrated call centers, extended ambulatory services and facilities for less urgent cases located in or nearby hospitals with EDs should also be implemented in Germany.


Assuntos
Serviço Hospitalar de Emergência , Seguro Saúde , Berlim , Alemanha , Pesquisas sobre Atenção à Saúde , Humanos , Inquéritos e Questionários , Estados Unidos
4.
Zentralbl Chir ; 141(6): 666-676, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27135864

RESUMO

Background: Up to 11 % of patients in an Emergency Department (ED) present with non-traumatic acute abdominal pain. Based on this presenting symptom, this study aimed to analyse how residents (surgery, internal medicine, anaesthesiology and other fields) working in an ED during their second and third year of education treat these patients. Material and Methods: We performed a prospective, monocentric observation study in an ED in accordance with the STROBE recommendations, following the recommendations from the Ethics Committee of the University of Ulm (application no. 335/12) and the Declaration of Helsinki. The hospital's data protection officer approved the study. During a 12-month period (Dec. 2012 to Dec. 2013), a random sample of patients with non-traumatic abdominal pain was obtained in the ED of a major German acute care hospital by an independent observer, who was not part of the ED team. In addition to demographic data, the study focused on analysing processes and patient care (including medical history taking and physical examinations). In addition, subgroups were defined (clinical background of the treating physician, severity pursuant to the Manchester Triage Score [MTS]). Results: 143 patients met the inclusion criteria. The clinical background of the physician had no influence on the reviewed processes such as medical history taking, initial examinations, the request of consultative examinations or diagnostic procedures. Patients triaged as "urgent" were treated significantly earlier than patients triaged as "non-urgent" (time to first physician contact 26 ± 24 vs. 46 ± 34 min, p < 0.001). However, the overall time spent in the ED was equal (210 ± 79 vs. 220 ± 114 min, p = 0.555). Yet the initially estimated urgency was correlated with the need for hospitalisation (share: 57 %). Conclusion: The overall compliance with standards of care was high. The clinical background (surgery, internal medicine, anaesthesiology, other fields) of the physician in charge of initial treatment had no influence on the reviewed processes.


Assuntos
Abdome Agudo/etiologia , Abdome Agudo/terapia , Medicina de Emergência/educação , Serviço Hospitalar de Emergência , Cirurgia Geral/educação , Internato e Residência , Adulto , Idoso , Currículo , Feminino , Alemanha , Hospitalização , Hospitais Universitários , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Encaminhamento e Consulta , Triagem
5.
Oncogene ; 34(34): 4545, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25619837

RESUMO

Correction to: Oncogene (2015) 34, 4448­4459; doi:10.1038/onc.2014.372; published online 24 November 2014. In this article, published online 24 November 2014, the authors have noticed that the latest supplementary information was not used. The corrected supplementary information (Supplementary Materials) appears online together with this corrigendum. The authors would like to apologise for any inconvenience this may cause

6.
Oncogene ; 34(34): 4448-59, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-25417704

RESUMO

Acquired drug resistance constitutes a major challenge for effective cancer therapies with melanoma being no exception. The dynamics leading to permanent resistance are poorly understood but are important to design better treatments. Here we show that drug exposure, hypoxia or nutrient starvation leads to an early innate cell response in melanoma cells resulting in multidrug resistance, termed induced drug-tolerant cells (IDTCs). Transition into the IDTC state seems to be an inherent stress reaction for survival toward unfavorable environmental conditions or drug exposure. The response comprises chromatin remodeling, activation of signaling cascades and markers implicated in cancer stemness with higher angiogenic potential and tumorigenicity. These changes are characterized by a common increase in CD271 expression concomitantly with loss of differentiation markers such as melan-A and tyrosinase, enhanced aldehyde dehydrogenase (ALDH) activity and upregulation of histone demethylases. Accordingly, IDTCs show a loss of H3K4me3, H3K27me3 and gain of H3K9me3 suggesting activation and repression of differential genes. Drug holidays at the IDTC state allow for reversion into parental cells re-sensitizing them to the drug they were primarily exposed to. However, upon continuous drug exposure IDTCs eventually transform into permanent and irreversible drug-resistant cells. Knockdown of CD271 or KDM5B decreases transition into the IDTC state substantially but does not prevent it. Targeting IDTCs would be crucial for sustainable disease management and prevention of acquired drug resistance.


Assuntos
Melanoma/tratamento farmacológico , Estresse Fisiológico , Animais , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Histona Desmetilases com o Domínio Jumonji/fisiologia , Camundongos , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/fisiologia , Proteínas Nucleares/fisiologia , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Receptores de Fator de Crescimento Neural/análise , Receptores de Fator de Crescimento Neural/fisiologia , Proteínas Repressoras/fisiologia , Transdução de Sinais
7.
Am J Transplant ; 14(10): 2206-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25091274

RESUMO

Chronic hepatitis C virus (HCV) infection remains an important health problem, which is associated with deleterious consequences in kidney transplant recipients. Besides hepatic complications, several extrahepatic complications contribute to reduced patient and allograft survival in HCV-infected kidney recipients. However, HCV infection should not be considered as a contraindication for kidney transplantation because patient survival is better with transplantation than on dialysis. Treatment of HCV infection is currently interferon-alpha (IFN-α) based, which has been associated with higher renal allograft rejection rates. Therefore, antiviral treatment before transplantation is preferable. As in the nontransplant setting, IFN-free treatment regimens, because of their greater efficacy and reduced toxicity, currently represent promising and attractive therapeutic options after kidney transplantation as well. However, clinical trials will be required to closely evaluate these regimens in kidney recipients. There is also a need for prospective controlled studies to determine the optimal immunosuppressive regimens after transplantation in HCV-infected recipients. Combined kidney and liver transplantation is required in patients with advanced liver cirrhosis. However, in patients with cleared HCV infection and early cirrhosis without portal hypertension, kidney transplantation alone may be considered. There is some agreement about the use of HCV-positive donors in HCV-infected recipients, although data regarding posttransplant survival rates are controversial.


Assuntos
Hepatite C Crônica/cirurgia , Transplante de Rim , Antivirais/uso terapêutico , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Humanos , Transplante de Rim/efeitos adversos
8.
J Clin Diagn Res ; 8(11): ZC138-40, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25584307

RESUMO

INTRODUCTION: Dental caries being a multi-factorial disease depends on lot of factors. Since awareness and exposure seems to have increased, in the present scenario it is difficult to assume that one particular source would increase the occurrence of dental caries. Children are exposed to different media sources and spend most of their free time watching them. They are attracted by messages of advertisers' and susceptible to stylish advertisements of foods often harmful to oral and general health. AIM: To compare the effects of three different sources of introduction to cariogenic food substance among school children and their role in caries prevalence. MATERIALS AND METHODS: A total of 300 school children were selected for the study and a questionnaire was prepared keeping in mind the various sources introducing cariogenic foods to children namely television advertisement, magazines/news paper, posters/banners. Following which oral examination will be done to determine the number of carious lesions in the subjects. The data will be acquired, computed and statistically analysed to compare the correlation between these sources and caries prevalence. RESULTS: Children who watched television advertisements and asked for food items and soft drinks were found to have more caries and DMFT/dmft index. CONCLUSION: A total ban on advertisements would not be practically possible. A more realistic approach would be to limit the number of advertisements that feature potentially cariogenic and unhealthy food products, and also ensure that they ideally carry statutory warnings.

9.
Transpl Infect Dis ; 14(5): 488-95, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22650645

RESUMO

UNLABELLED: The development of liver and graft disease is suspected to be affected by genetic diversity. Mannose-binding lectin-2 (MBL-2) is an important immunomodulatory factor that is involved in complement activation. The aim of our study was to elucidate the role of MBL-2 genotypes after liver transplantation (LT) for hepatitis C virus (HCV)-induced liver disease regarding the incidence of acute cellular rejection (ACR), graft inflammation, fibrosis development, and antiviral treatment response. METHODS: A group of 149 patients who underwent LT for HCV-induced liver disease were genotyped for MBL-2 (rs7096206; G/C) by TaqMan genotyping assay. We evaluated 518 post-LT protocol biopsies and at least 98 urgent liver biopsies regarding graft fibrosis stages, inflammation grades, and evidence for rejection within MBL-2 genotype groups. RESULT: No association of MBL-2 polymorphisms was observed regarding inflammation, fibrosis, and antiviral treatment outcome. However, the C allele of the MBL-2 gene (P = 0.001) and gender compatibility (P = 0.012) were factors significantly associated with the incidence of ACR. CONCLUSION: MBL-2 polymorphisms and gender are involved in the development of ACR after LT. CC genotype and gender match may be regarded as risk factors for ACR in HCV-positive graft recipients. Further studies are needed to confirm and verify this observation in non-HCV groups as well.


Assuntos
Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/genética , Hepacivirus/patogenicidade , Hepatopatias/terapia , Transplante de Fígado/efeitos adversos , Lectina de Ligação a Manose/genética , Polimorfismo Genético , Feminino , Rejeição de Enxerto/etiologia , Hepatite C/virologia , Humanos , Incidência , Cirrose Hepática/epidemiologia , Cirrose Hepática/virologia , Hepatopatias/virologia , Masculino , Fatores Sexuais
11.
Eur J Microbiol Immunol (Bp) ; 2(3): 186-91, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24688764

RESUMO

Diseases such as liver fibrosis and intestinal inflammation are characterized by accumulated components of the extracellular matrix (ECM). Given that fibrillar collagen structures were shown to serve as storage site for inactive proforms of matrixmetalloproteinases (MMPs), modulating this MMP-collagen interaction might offer a rational interventional (therapeutic) approach to enhance degradation of accumulated ECM. The synthetic triple helical collagen analogue (Gly-Pro-Hyp)10 - (GPO)10 - was shown to trigger release and enzymatic activation of collagen sequestered proMMP-2. In the presented study, we, for the first time, investigated how MMP-(GPO)10 interaction impacts cellular responses in vitro. We found that recombinant proMMP-2 induced proliferation of hepatic stellate cells (HSC), which was enhanced after addition of (GPO)10 reaching comparable levels following incubation with fully activated MMP-2. In addition, (GPO)10 induced HSC migration similar to the platelet-derived growth factor subunit-B. Further, the MMP-2-dependent invasion of HT1080 fibrosarcoma cells through an ECM membrane was enhanced after addition of (GPO)10. Since cellular proliferation and migration concomitant with matrix degradation is stimulated, we conclude that the MMP-(GPO)10 interaction also functions in a physiological environment. Thus, a potential therapeutic effect of (GPO)10 should be further tested in animal models for MMP-associated diseases such as colitis or fibrosis.

12.
Eur J Microbiol Immunol (Bp) ; 2(3): 192-200, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24688765

RESUMO

In experimental models of and humans with intestinal inflammation, increased levels of the matrix-degrading gelatinases MMP-2 and -9 in inflamed tissues can be detected. The synthetic collagen analogue (Gly-Pro-Hyp)10, (GPO)10, has been identified as a relevant binding structure for proMMP-2/-9 and promotes enzymatic activity of proMMP-2. Since targeted MMP strategies might offer promising anti-inflammatory treatment options, we for the first time studied in vivo actions exerted by (GPO)10 applying an acute dextrane sulfate sodium (DSS) induced colitis model. Seven-day intraperitoneal (GPO)10 treatment ameliorated clinical symptoms and histopathological colonic changes as compared to placebo controls with severe colitis. (GPO)10-treated mice displayed a diminished influx of neutrophils, and T- and B-lymphocytes into their colonic mucosa whereas numbers of regulatory T-cells and regenerative cells were higher as compared to placebo controls. Furthermore, IL-6 secretion was down-regulated in ex vivo colonic biopsies derived from (GPO)10-treated mice whereas higher concentrations of the anti-inflammatory cytokine IL-10 in extra-intestinal compartments such as MLN and spleen could be detected. Strikingly, influx of inflammatory cells into lungs was abolished following (GPO)10 application. We therefore propose (GPO)10 as a promising effective and safe treatment option of intestinal and extra-intestinal inflammatory conditions in humans.

13.
Int J Clin Pharmacol Ther ; 47(3): 165-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19281725

RESUMO

OBJECTIVE: To report a case of an uncommon and up to date unpublished peracute and overwhelming muscle pain following administration of ciprofloxacin. CASE SUMMARY: A 58-year-old male developed fulminating musculoskeletal pain associated with third-time exposure to ciprofloxacin administered for treatment of chronic otitis media. Symptoms resolved slowly after intense combined analgetic therapy and cessation of ciprofloxacin therapy. 24 h after ciprofloxacin discontinuation the symptoms had completely disappeared and no more analgetic treatment was needed. Laboratory values, especially muscle enzymes, did not reveal any pathological pattern. The patient's past medical history highlighted reproducible side effects with both systemic and local administration of ciprofloxacin including milder symptoms of the musculoskeletal system. DISCUSSION: Common side effects of fluoroquinolones include gastrointestinal, central nervous and allergic reactions, but also more uncommon reactions such as tendonitis and rhabdomyolysis. In our case, there had been no signs of rhabdomyolysis. Besides an elevated IgE level no clinical signs of a true anaphylactic reaction associated with release of mast cell mediators had been observed. A pharmacokinetic interaction between ciprofloxacin and the patient's comedication carbamazepine is unlikely to be the responsible mechanism, since fluoroquinolones inhibit cytochrome P450 isoenzyme CYP1A2 but not CYP3A4 which metabolizes carbamazepine. CONCLUSION: To our knowledge, this is the first report describing fulminating musculoskeletal pain following administration of ciprofloxacin without any signs of rhabdomyolysis. Physicians should notice that there is a variety of adverse reactions of this usually well-tolerated agent and they should be aware of unusual complaints of their patients who receive fluoroquinolone treatment.


Assuntos
Antibacterianos/efeitos adversos , Ciprofloxacina/efeitos adversos , Doenças Musculares/induzido quimicamente , Dor/induzido quimicamente , Doença Aguda , Antibacterianos/uso terapêutico , Doença Crônica , Ciprofloxacina/uso terapêutico , Emergências , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Doenças Musculares/tratamento farmacológico , Otite Média/tratamento farmacológico , Dor/tratamento farmacológico
14.
Rofo ; 180(12): 1104-9, 2008 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-18814103

RESUMO

PURPOSE: Recent magnetic resonance elastography (MRE) studies have reported the potential of this noninvasive method for diagnosing hepatic fibrosis based on the elastic properties of liver tissue. However, in many cases biological tissue responds to mechanical vibrations as a combined solid-liquid body causing MRE-derived elastic parameters to become functions of the applied vibration frequency. Therefore a multi-frequency MRE study of liver was performed and the potential of the method for separating healthy from fibrotic liver was investigated. The aim of this study was the increase of the accuracy of liver elastography by analyzing multi-frequency MRE examinations using the springpot model. MATERIALS AND METHODS: 18 healthy volunteers and 10 patients were examined by multi-frequency MRE of the liver in a frequency range between 25 Hz and 62.5 Hz. The liver was mechanically excited with four harmonic vibrations simultaneously. The measured dispersion of the complex modulus was analyzed using the springpot model which accounts for both elastic and viscous properties of a material with 2 independent parameters. RESULTS: The mechanical stimulation and the motion encoding according to the multi-frequency approach was implemented successfully. Significant differences (p < 0.05) were found in the hepatic viscoelasticities of normal livers. The separation of healthy volunteers and patients was achieved with a sensitivity and specificity of 80 and 100 %, respectively. CONCLUSION: Using the springpot model, multi-frequency MRE is sensitive to interindividual differences in the hepatic viscoelastic properties of healthy volunteers. The obtained accuracy of the technique in separating healthy from fibrotic livers opens the possibility of applying multi-frequency MRE as a noninvasive method for diagnosing liver fibrosis in the future.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Cirrose Hepática/diagnóstico , Adulto , Idoso , Fenômenos Biomecânicos , Elasticidade , Feminino , Humanos , Fígado/fisiopatologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sensibilidade e Especificidade , Vibração , Viscosidade
15.
Dtsch Med Wochenschr ; 133(38): 1897-900, 2008 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-18788068

RESUMO

HISTORY: A 48-year-old patient with Crohn's disease was admitted to our hospital with fatigue, icterus, hepatosplenomegaly and ascites. INVESTIGARTIOS: The whole blood count revealed a pancytopenia, hyperbilirubinemia and slightly elevated transaminases. Examination of the liver histology showed areas of enlarged hyperplastic hepatocytes adjacent to areas of atrophic hepatocytes and dilated sinusoids. DIAGNOSIS, TREATMENT AND COURSE: Pancytopenia was most likely azathioprine-related. Analysis of the liver histology was highly suggestive of an azathioprine-related, nodular regenerative hyperplasia (NRH). After discontinuation of azathioprine the patient's condition improved substantially. CONCLUSIONS: NRH is a rare but potentially serious complication of azathioprine therapy. Other causes include various rheumatological, vascular and myeloproliferative diseases. When azathioprine is prescribed it must be borne in mind that it can cause NRH as a potential adverse effect, and liver enzymes should be measured at regular follow-up examinations.


Assuntos
Azatioprina/efeitos adversos , Doença de Crohn/tratamento farmacológico , Hiperplasia Nodular Focal do Fígado/induzido quimicamente , Imunossupressores/efeitos adversos , Ascite/etiologia , Azatioprina/uso terapêutico , Contagem de Células Sanguíneas , Diagnóstico Diferencial , Fadiga/etiologia , Hiperplasia Nodular Focal do Fígado/complicações , Hiperplasia Nodular Focal do Fígado/patologia , Humanos , Imunossupressores/uso terapêutico , Icterícia/etiologia , Fígado/enzimologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Pancitopenia/induzido quimicamente
16.
Colloids Surf B Biointerfaces ; 62(1): 125-9, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17988840

RESUMO

In the present investigation, five varieties of okra (Abelmoschus esculentus (L.) Moench.) were screened for their water use efficiency under two water regimes, viz., 60% and 100% filed capacity. Drought stress was imposed at 60% field capacity from 30 to 70 days after sowing, while the control pots were maintained at 100% field capacity throughout the period of entire growth. Biomass and yield, leaf area duration, cumulative water transpired water use efficiency, net assimilation rate, mean transpiration rate and harvest index under water deficit level were measured. Water use efficiency significantly increases in all the okra varieties under water-limited environment. Drought stress decreased the biomass and yield, leaf area duration, cumulative water transpired, net assimilation rate, mean transpiration rate and harvest index in the okra varieties studied. But among the varieties, variety JK Haritha showed better results. None of the varieties studied had showed increased drought tolerance than the control.


Assuntos
Abelmoschus/metabolismo , Água/metabolismo , Desastres
17.
Colloids Surf B Biointerfaces ; 62(1): 58-63, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17983733

RESUMO

Experiments were conducted to study the effects of different sodium salts viz., sodium chloride (NaCl), sodium sulphate (Na(2)SO(4)) and sodium carbonate (Na(2)CO(3)) on growth, dry matter production, mineral contents, biochemical constituent and enzyme activities of sunflower (Helianthus annuus L.). The germinating sunflower seeds were treated with 10, 20 and 50mM NaCl and Na(2)SO(4) and 5, 10 and 15 mM Na(2)CO(3). The seedling growth, minerals, chlorophyll content and biochemicals like protein and free amino acid contents with enzyme activities like ATPase and protease were analysed on 8 DAS. The seedlings were separated into root, stem, leaf and cotyledon on 8 DAS. All the treatments decreased the germination percentage; shoot length, root length, leaf area and dry weight, chlorophyll and protein contents significantly. Potassium, sodium and free amino acid contents; activities of ATPase and protease were increased when compared to control. This effect was very high in the Na(2)CO(3) treated seedlings this was followed by Na(2)SO(4) and NaCl treated seedlings. From the results of this investigation, it is clear that, the sunflower seedlings were affected significantly in the Na(2)CO(3) treatments, and followed by Na(2)SO(4) and NaCl treatments.


Assuntos
Helianthus/metabolismo , Sódio/farmacologia , Adenosina Trifosfatases/metabolismo , Carbonatos/farmacologia , Carboxipeptidase B/metabolismo , Clorofila/metabolismo , Helianthus/efeitos dos fármacos , Helianthus/crescimento & desenvolvimento , Potássio/metabolismo , Sódio/metabolismo , Cloreto de Sódio/farmacologia , Sulfatos/farmacologia
18.
Colloids Surf B Biointerfaces ; 61(2): 315-8, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17961996

RESUMO

A pot culture experiment was conducted to estimate the stress ameliorating ability of paclobutrazol, a triazole fungicide in Vigna unguiculata (L.) Walp. plants. Treatments were given as 80 mM NaCl, 80 mM NaCl+15 mg l(-1) paclobutrazol and 15 mg l(-1) paclobutrazol alone. The samples were collected on 60 and 80 days after sowing (DAS). NaCl stress inhibited the root and stem length, total leaf area, fresh weight (FW), dry weight (DW) and activities of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX). Plants treated with NaCl with paclobutrazol increased these parameters to a larger extent when compared to NaCl stressed plants. The results showed that the paclobutrazol significantly ameliorated the adverse effects of NaCl stress in V. unguiculata plants.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Fabaceae/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Triazóis/farmacologia , Antioxidantes/metabolismo , Catalase/metabolismo , Fabaceae/enzimologia , Fabaceae/crescimento & desenvolvimento , Fungicidas Industriais/farmacologia , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo
19.
Colloids Surf B Biointerfaces ; 60(2): 229-35, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17764913

RESUMO

An investigation was carried out to find out the extent of changes occurred in groundnut (Arachis hypogaea L.) cultivars in response to paclobutrazol (PBZ) treatment under water deficit stress. Two groundnut cultivars namely ICG 221 and ICG 476 were used for the study. Individual treatment with PBZ and drought stress showed an increase in ascorbic acid, alpha-tocopherol and reduced glutathione, superoxide dismutase (SOD), ascorbate peroxidase (APX) and catalase (CAT) activities. PBZ with drought stressed plants maintained higher levels of antioxidant and scavenging enzymes. Significant differences were observed between cultivars and treatments. These results suggests that the adverse effects of water stress can be minimized by the application of PBZ by increasing the antioxidant levels and activities of scavenging enzymes such as SOD, APX and CAT. The Cv. ICG 221 appears to be more tolerant to water stress than the ICG 476.


Assuntos
Antioxidantes/metabolismo , Arachis/metabolismo , Catalase/metabolismo , Peroxidases/metabolismo , Superóxido Dismutase/metabolismo , Triazóis/farmacologia , Antioxidantes/química , Arachis/química , Arachis/efeitos dos fármacos , Ascorbato Peroxidases , Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Catalase/química , Catalase/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/metabolismo , Fungicidas Industriais/farmacologia , Glutationa/química , Glutationa/metabolismo , Peroxidases/química , Peroxidases/efeitos dos fármacos , Superóxido Dismutase/química , Superóxido Dismutase/efeitos dos fármacos , Água/química , alfa-Tocoferol/química , alfa-Tocoferol/metabolismo
20.
Colloids Surf B Biointerfaces ; 60(1): 7-11, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17681765

RESUMO

The effect of plant growth promoting rhizobacteria (PGPR) like Pseudomonas fluorescens on growth parameters and the production of ajmalicine were investigated in Catharanthus roseus under drought stress. The plants under pot culture were subjected to 10, 15 and 20 days interval drought (DID) stress and drought stress with Pseudomonas fluorescens at 1mgl(-1) and 1mgl(-1)Pseudomonas fluorescens alone from 30 days after planting (DAP) and regular irrigation was kept as control. The plants were uprooted on 41 DAS (10 DID), 46 DAS (15 DID) and 51 DAS (20 DID). Drought stress decreased the growth parameters and increased the ajmalicine content. But the treatment with Pseudomonas fluorescens enhanced the growth parameters under drought stress and partially ameliorated the drought induced growth inhibition by increasing the fresh and dry weights significantly. The ajmalicine content was again increased due to Pseudomonas fluorescens treatment to the drought stressed plants. From the results of this investigation, it can be concluded that, the seedling treatments of native PGPRs can be used as a good tool in the enhancement of biomass yield and alkaloid contents in medicinal plants, as it provides an eco-friendly approach and can be used as an agent in water deficit stress amelioration.


Assuntos
Biomassa , Catharanthus/metabolismo , Catharanthus/microbiologia , Desidratação/metabolismo , Pseudomonas fluorescens/fisiologia , Alcaloides de Triptamina e Secologanina/metabolismo , Água/metabolismo , Catharanthus/anatomia & histologia , Catharanthus/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA