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1.
Environ Sci Pollut Res Int ; 30(60): 125559-125569, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37999850

RESUMO

This study analyses particulate organic carbon (POC) and particulate nitrogen (PN) export from Indian monsoonal rivers to the north Indian Ocean. Indian monsoonal rivers export approximately 1.2 Tg yr-1 (1Tg = 1012 g) of POC and 0.14 Tg yr-1 of PN, with about two-thirds entering the Bay of Bengal (0.8 and 0.1 Tg yr-1, respectively) and the remaining reaches to the Arabian Sea (0.4 and 0.04 Tg yr-1, respectively). Remarkably, just four rivers from northwest India's black soil-dominated regions contribute about half of the total POC and PN exports (0.64 and 0.06 Tg yr-1, respectively). This is due to substantial erosion in these catchments, resulting in suspended matter concentrations averaging 596 ± 252 mg L-1, significantly higher than catchments dominated by red sandy, red loamy and alluvial soils (54 ± 56 mg l-1). In contrast, rivers originating from catchments with heavy precipitation, a tropical wet climate, red loamy soils (with peaty and marshy characteristics), rich tropical wet evergreen and moist deciduous forests, and higher soil organic carbon content yield more POC and PN (1704 ± 383 kgC km-2 yr-1 and 261 ± 56 kgN km-2 yr-1, respectively) than the other rivers of India (951 ± 508 kgC km-2 yr-1 and 120 ± 57 kgN km-2 yr-1, respectively). These findings stress that the export flux and yield of POC and PN from the Indian monsoonal rivers are primarily influenced by the interplay of hydrological, lithological, environmental, and climatic conditions within the catchment, rather than river size. Moreover, this study highlights the significant impact of incorporating POC data from medium-sized rivers worldwide, as it reveals that yield is independent of river size. This calls for a re-evaluation of global POC export fluxes, taking into account hydrological, lithological, environmental, and climatic factors.


Assuntos
Carbono , Nitrogênio , Carbono/análise , Nitrogênio/análise , Oceano Índico , Rios , Solo , Poeira/análise , Monitoramento Ambiental
2.
Narra J ; 3(3): e413, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38450333

RESUMO

Pregnant women have a number of physiological changes that lower the immune responses to avoid embryonic rejection, which increases the risk of problems after contracting coronavirus disease 2019 (COVID-19). Multiple inflammatory cytokines are dysregulated in this process and expressed inappropriately during systemic inflammatory responses associated with COVID-19. The aim of the study was to compare the levels of vascular cell adhesion molecule 1 (VCAM-1), a marker of endothelial damage in pregnancies with and without COVID-19. A cohort prospective study was conducted at H. Adam Malik General Hospital and the Universitas Sumatera Utara Hospital, Indonesia. Pregnant women without COVID-19 and pregnant women with moderate and severe degrees of COVID-19 were recruited. The level of VCAM-1 was measured at three different time points (during pregnancy, within an hour of placental detachment, and 24 hours postpartum). The ANOVA and Student t-test were used to compare the VCAM-1 levels among different time points and between groups, respectively. The mean VCAM-1 levels at the hospital admission, one hour of placental detachment and 24 hours postpartum in non-COVID-19 and COVID-19 pregnancies were 591.29 vs 1176.27 pg/mL; 558.2 vs 1136.2 pg/mL; and 508.59 vs 985.2 pg/mL, respectively. There was a significant different in VCAM-1 levels in normal pregnancy at the time of hospital admission, one hour after detachment of the placenta and 24 hours postpartum (p=0.04). The mean VCAM-1 levels in pregnant women with COVID-19 also had significant differences between three time points (p=0.033). The levels of VCAM-1 were statically higher among pregnancy in the COVID-19 group compared to the non-COVID-19 group during hospital admission (p=0.023), one hour after placenta detachment (p=0.040) and 24 hours postpartum (p=0.043). The results suggested the usefulness of identifying the VCAM-1 level as a marker of endothelial dysfunction in pregnancy with COVID-19.

3.
Open Access Maced J Med Sci ; 7(7): 1153-1159, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31049099

RESUMO

BACKGROUND: Reducing maternal mortality is one of the targets in the Millennium Development Goals (MDGs). In a systematic review, 4.6 per cent (95% CI 2.7-8.2) of pregnancies were complicated by preeclampsia worldwide. Preeclampsia occurs in around 10% of pregnancies in the world whereas developing countries contribute more than developed countries. In developing countries, there are 13 cases of preeclampsia in every 1,000 births, whereas in developed countries only 2-3 cases of preeclampsia are found in every 10,000 deliveries. Variations in prevalence among countries reflect, at least in part, differences in the distribution of maternal age and the proportion of nulliparous pregnant women in the population. AIM: We aimed to investigate the role of placental growth factor, soluble endoglin, and uterine artery diastolic notch to predict the early onset of preeclampsia. METHODS: This study used an analytical study with a nested case-control design. The study was conducted at Bunda Thamrin Hospital, Tanjung Mulia Mitra Medika Hospital, Sundari Hospital and a private clinic, from March to November 2018 with a total sample of 70 research subjects. RESULTS: Uterine artery diastolic notch was not found in 50% of subjects. A total of 27 subjects (38.6%) had a unilateral diastolic notch, and 8 subjects (11.4%) had a bilateral diastolic notch. Cut-off point PIGF levels was 441 pg/ml, and Area Under Curve (AUC) 82.5% (95% CI 61.5%-100%), with sensitivity 80% and specificity 87.7%. The levels sEng in this study could not predict the incidence of early-onset preeclampsia (p = 0.113). Combined PlGF and pulsatile index of uterine arteries may predict early onset preeclampsia with sensitivity 40% and specificity 90.77%. From these results, pregnant women o 22-24 weeks of pregnancy, the levels of PlGF and the uterine artery pulsatility index can be a predictor of early-onset preeclampsia. Examination of PlGF levels alone is sufficient as a predictor of early-onset preeclampsia. CONCLUSION: From these results, it can be concluded that in pregnant women of 22-24 weeks, the diastolic notches in uterine arteries cannot predict the incidence of early-onset preeclampsia. PlGF levels and pulsatile index of uterine arteries can be used as predictors of early-onset preeclampsia although examination of PlGF levels alone is sufficient as a predictor of early-onset preeclampsia.

4.
Anaesth Intensive Care ; 46(3): 297-303, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29716488

RESUMO

The influence of variables that might affect the accuracy of pulse oximetry (SpO2) recordings in critically ill patients is not well established. We sought to describe the relationship between paired SpO2/SaO2 (oxygen saturation via arterial blood gas analysis) in adult intensive care unit (ICU) patients and to describe the diagnostic performance of SpO2 in detecting low SaO2 and PaO2. A paired SpO2/SaO2 measurement was obtained from 404 adults in ICU. Measurements were used to calculate bias, precision, and limits of agreement. Associations between bias and variables including vasopressor and inotrope use, capillary refill time, hand temperature, pulse pressure, body temperature, oximeter model, and skin colour were estimated. There was no overall statistically significant bias in paired SpO2/SaO2 measurements; observed limits of agreement were +/-4.4%. However, body temperature, oximeter model, and skin colour, were statistically significantly associated with the degree of bias. SpO2 <89% had a sensitivity of 3/7 (42.9%; 95% confidence intervals, CI, 9.9% to 81.6%) and a specificity of 344/384 (89.6%; 95% CI 86.1% to 92.5%) for detecting SaO2 <89%. The absence of statistically significant bias in paired SpO2/SaO2 in adult ICU patients provides support for the use of pulse oximetry to titrate oxygen therapy. However, SpO2 recordings alone should be used cautiously when SaO2 recordings of 4.4% higher or lower than the observed SpO2 would be of concern. A range of variables relevant to the critically ill had little or no effect on bias.


Assuntos
Oximetria , Oxigênio/sangue , Troca Gasosa Pulmonar , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Estudos Prospectivos
5.
Luminescence ; 32(3): 401-408, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27511527

RESUMO

In this work, we report the synthesis, characterization and biological application of highly stable CdTe/ZnS (cadmium tellurite/zinc sulphide) Core/Shell (CS) quantum dots (QDs) capped with mercaptosuccinic acid (MSA). The CS QDs were synthesized using a simple one-pot aqueous method. The synthesized CdTe/ZnS CS QDs were found to exhibit excellent stability even 100 days after preparation and also showed better photoluminescence quantum yield (PLQY) of about 50% compared with that of only CdTe QDs which was nearly 12%. The formation of the CdTe/ZnS CS was confirmed by high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infra-red (FTIR) and X-ray diffraction (XRD) analyses. Further, on extending our study towards bioimaging of E. coli cells using the QDs samples, we found that CdTe/ZnS CS QDs showed better results compared with CdTe QDs.


Assuntos
Compostos de Cádmio/química , Escherichia coli/citologia , Medições Luminescentes , Pontos Quânticos , Sulfetos/química , Telúrio/química , Compostos de Zinco/química , Células Cultivadas , Água/química
6.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4236-4239, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25812055

RESUMO

Malaria is a major public health problem in north-east India mainly transmitted by Anopheles baimai and An. minimus while Anopheles nivipes plays an important supportive role. The genetic diversity of An. nivipes in north-east India was investigated by employing two mitochondrial DNA markers namely NADH dehydrogenase 5 (ND5) and cytochrome oxidase sub unit II (COII). High genetic diversity in An. nivipes was observed by the detection of 16 haplotypes among 30 sequences of ND5 gene and 29 haplotypes among 29 COII sequences. Anopheles nivipes of north-east India was significantly differentiated genetically with that of neighboring South-east Asian An. nivipes as revealed by pairwise FST values of 0.127 (p < 0.01) and 0.044 (p < 0.001) for ND5 and COII genes, respectively, suggesting geographical barriers to gene flow in this species between the two geographical areas resulting in significant population structuring.


Assuntos
Anopheles/genética , DNA Mitocondrial/genética , Variação Genética/genética , Genoma Mitocondrial/genética , Mitocôndrias/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fluxo Gênico/genética , Marcadores Genéticos/genética , Haplótipos/genética , Índia , Análise de Sequência de DNA/métodos
7.
Am J Transplant ; 15(7): 1933-47, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25649290

RESUMO

The pathogenesis of chronic rejection, Bronchiolitis Obliterans Syndrome (BOS) following lung transplantation (LT) is poorly understood. We hypothesized that development of antibodies to HLA (DSA) is associated with dysregulation of microRNA (miRNA) that predisposes BOS. Towards this, miRNA profiling of mononuclear cells from 10 stable LT (DSA(-) BOS(-) ), 10 LT with DSA(+) BOS(-) (DSA group) and 10 LT with DSA(+) BOS(+) (BOS group) were performed. Prediction by mirPath indicated that differential miRNAs in DSA(+) BOS(-) compared to stable are significantly up-regulated (relative fold >2, p < 0.05) for TGF-ß and B cell receptor signal pathways. A total of seventy-four miRNAs were up-regulated and six miRNAs were down regulated in LT with DSA(+) BOS(+) when compared to stable (relative fold >2, p < 0.05). There was also significant enrichment of cell cycle and gap junction pathways. An inverse correlation between expression of two key miRNAs and their target genes were observed: miR-369-5p and miR-548d were down regulated in DSA(+) LT while their gene targets in TGF-ß signal pathways were up-regulated. In addition, miR-628-5p and miR-134 were down regulated and their target genes (B cell development) were up-regulated. Therefore, we conclude that alloimmunity induced changes in miRNAs affecting the TGF-ß and B cell receptor signal pathways play important roles in BOS development.


Assuntos
Bronquiolite Obliterante/cirurgia , Rejeição de Enxerto/etiologia , Antígenos HLA/imunologia , Isoanticorpos/imunologia , Transplante de Pulmão , MicroRNAs/genética , Aloenxertos , Bronquiolite Obliterante/complicações , Feminino , Seguimentos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Antígenos HLA/genética , Humanos , Isoanticorpos/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Doadores de Tecidos , Fator de Crescimento Transformador beta/genética , Transplantados
8.
Acta Trop ; 124(1): 62-70, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22771401

RESUMO

Anopheles (Cellia) maculatus is considered a group of at least nine formally named species. Faced with the difficulty of correct morphological identification due to overlapping characters, several member species of the An. maculatus group are known to play important role in malaria transmission in the Oriental region. Current assemblage, distribution and vectorial importance of the member species within the Maculatus group is far from clear in the north-eastern region of India. Our study encompassing 410 individuals, collected from 67 geo-referenced spots across the eight north-east Indian states, identified the presence of 6 member species of the Maculatus group using the molecular tools. Anopheles dravidicus and Anopheles rampae were documented for the first time in this part of India with latter forming the new country record. While Anopheles pseudowillmori (59.5%) and An. maculatus (32%) were widely available species in most of the north-eastern states, restricted distribution of Anopheles willmori to Nagaland and that of Anopheles sawadwongporni and An. rampae to Mizoram state was noted. None of the species was found positive for human malaria parasite. While no intraspecific differences existed in the sequences of second internal transcribed spacer (ITS2) region of ribosomal DNA (r-DNA) of the member species of the Maculatus group within north-east India, few differences were detected in the sequences of An. dravidicus, An. maculatus and An. pseudowillmori from north-east India with species from the neighbouring countries.


Assuntos
Anopheles/classificação , Anopheles/genética , Filogeografia , Animais , Anopheles/parasitologia , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Vetores de Doenças , Índia , Dados de Sequência Molecular , Plasmodium/isolamento & purificação , Análise de Sequência de DNA
9.
Int J Immunogenet ; 39(5): 373-80, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22486939

RESUMO

Organ transplantation is the treatment of choice for patients with end-stage organ dysfunction. In spite of advances in understanding of donor and recipient physiology, organ preservation, operative techniques and immunosuppression, long-term graft survival still remains a major problem primarily due to chronic rejection. Alloimmune responses to mismatched major histocompatibility antigens have been implicated as an important factor leading to rejection. However, there is increasing evidence pointing towards cross-talk between the alloimmune and autoimmune responses creating a local inflammatory milieu, which eventually leads to fibrosis and occlusion of the lumen in the transplanted organ i.e. chronic rejection. In this review, we will discuss recent studies and emerging concepts for the interdependence of alloimmune and autoimmune responses in the immunopathogenesis of chronic allograft rejection. The role of autoimmunity in the development of chronic rejection is an intriguing and exciting area of research in the field of solid-organ transplantation with a significant potential to develop novel therapeutic strategies towards preventing chronic allograft rejection.


Assuntos
Autoimunidade , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Transplante de Órgãos/efeitos adversos , Animais , Autoanticorpos/imunologia , Autoantígenos/imunologia , Miosinas Cardíacas/imunologia , Antígenos HLA/imunologia , Humanos , Contagem de Linfócitos , Transplante de Órgãos/patologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia
10.
Acta Trop ; 122(3): 247-54, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22374100

RESUMO

Anopheles philippinensis-nivipes species of mosquitoes are considered secondary malaria vectors in the north-east India. However, difficulty in separating An. philippinensis and An. nivipes accurately on the basis of morphological identification, due to the overlapping female wing characters, has led to the paucity of information on their spatial distribution and vectorial importance, essential for understanding malaria disease epidemiology in areas under their influence. In view of this a study was undertaken to generate authentic information on distribution of An. philippinensis and An. nivipes in the north-east India using molecular tools. Between the two, An. nivipes was recorded as the dominant species in Assam, and Nagaland states whereas An. philippinensis was found predominant in the state of Mizoram and Arunachal Pradesh. Species differentiation based on female wing characters proved wrong in about 74% specimens of An. philippinensis but found accurate in case of An. nivipes. No intra-specific variation in second internal transcribed spacer (ITS2) region of ribosomal DNA(r-DNA) in either An. nivipes or An. philippinensis from different geographical areas of north-east India was noted.


Assuntos
Anopheles/classificação , Anopheles/crescimento & desenvolvimento , Animais , Anopheles/anatomia & histologia , Anopheles/genética , Sequência de Bases , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Demografia , Feminino , Índia , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético , Alinhamento de Sequência , Análise de Sequência de DNA , Asas de Animais/anatomia & histologia
11.
Bioresour Technol ; 102(24): 11212-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22014704

RESUMO

Laboratory investigation on vermicomposting efficacy of Perionyx excavatus for recycling of distillation waste biomass of java citronella (Cymbopogon winterianus Jowitt) was carried out in two seasonal trials i.e. summer and winter periods. The experiment was conducted in earthen pots using a mixture of citronella waste material and cowdung in the proportion of 5:1. A control treatment without earthworms was setup for comparison of the results. The vermicompost had shown 5.8 folds reduction in C/N ratio and 5.6 folds enhancement in ash content. The nutrient contents (N, P, K, Ca and Mg) in the vermicompost had increase in the range of 1.2 - 4.1 fold than the initial level. The FT-IR spectra of the vermicompost confirmed increase in nitrogen rich compounds and decrease in aliphatic/aromatic compounds as compared to the initial level of the biowaste materials. The vermicomposting process is influenced by seasonal variation and summer was more productive than winter.


Assuntos
Biomassa , Cymbopogon/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Oligoquetos/fisiologia , Óleos de Plantas/metabolismo , Reciclagem , Resíduos/análise , Animais , Biodegradação Ambiental , Carbono/análise , Bovinos , Fezes , Concentração de Íons de Hidrogênio , Indonésia , Metais Pesados/análise , Nitrogênio/análise , Estações do Ano , Solo , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Bioresour Technol ; 102(13): 6944-50, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21550233

RESUMO

Laboratory experiment on vermicomposting of distillation waste of java citronella (Cymbopogon winterianus Jowitt.) was carried out employing Eudrilus eugeniae, in two seasonal trials, covering summer and winter periods. Two vermicomposting treatments were conducted in earthen pots, one with citronella plant waste only (CW) and the other, a mixture of citronella waste and cowdung in the proportion 5:1 (CW+CD). Vermicomposting of citronella waste resulted reduction in C/N ratio (83.5-87.7%), enhancement of ash content and a number of macro and micronutrients. The FT-IR spectroscopy of the vermicompost revealed the reduction in aliphatic and aromatic compound as well as increase in amide group after the 105 days stabilization process. The vermicompost output was significantly enhanced in CW+CD treatment than CW treatment. Even, nutrient content of the vermicompost was also higher in CW+CD treatment than CW alone indicating the positive role of cowdung in improvement of quantity and quality.


Assuntos
Biotecnologia/métodos , Cymbopogon/química , Destilação , Oligoquetos/fisiologia , Solo/análise , Resíduos/análise , Animais , Biodegradação Ambiental , Biomassa , Carbono/análise , Fenômenos Químicos , Nitrogênio/análise , Estações do Ano , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Singapore Med J ; 52(2): e31-4, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21373727

RESUMO

An increasing number of patients with chronic hepatitis B infection are being treated with the newly licensed drug, adefovir. It is an acyclic nucleoside phosphonate that is relatively safe in the dosage generally used for chronic hepatitis B. Serious adverse cutaneous drug reactions like Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) following adefovir use have not been reported. We report a case of adefovir-induced SJS and TEN overlap syndrome in a patient with chronic hepatitis B infection.


Assuntos
Adenina/análogos & derivados , Antivirais/efeitos adversos , Hepatite B Crônica/tratamento farmacológico , Organofosfonatos/efeitos adversos , Síndrome de Stevens-Johnson/induzido quimicamente , Síndrome de Stevens-Johnson/etiologia , Adenina/efeitos adversos , Adenina/uso terapêutico , Antivirais/uso terapêutico , Biópsia , Epiderme/ultraestrutura , Seguimentos , Humanos , Imunossupressores , Masculino , Pessoa de Meia-Idade , Organofosfonatos/uso terapêutico , Fotomicrografia , Síndrome de Stevens-Johnson/diagnóstico
14.
Ann Trop Med Parasitol ; 104(4): 331-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20659394

RESUMO

The Anopheles philippinensis and An. nivipes mosquitoes that form part of the An. annularis species group are morphologically very similar and difficult to differentiate as adults. In consequence, researchers generally refer to all field-collected individuals of these species simply as the An. philippinensis-nivipes species complex. Although this species complex is understood to play a role in the transmission of parasites causing human malaria in north-eastern India, the identity of the exact species involved, and the relative importance of the local An. philippinensis and An. nivipes, are far from clear. To settle this issue, house-frequenting female adults of the An. philippinensis-nivipes species complex were collected from 23 localities in the six north-eastern states, identified to species (using an allele-specific PCR to explore the insects' ribosomal-DNA internal-transcribed-spacer-2 sequences) and checked for Plasmodium DNA (using a nested PCR based on the 18S subunit of the parasite's ribosomal DNA). Of the 337 females of the An. philippinensis-nivipes species complex that were investigated, 275 were identified as An. nivipes and 62 as An. philippinensis. Malarial infection was detected in the heads/thoraces of just two specimens, with P. falciparum DNA detected in one An. nivipes from Nagaland state and one An. nivipes from Assam state. These results provide unambiguous evidence of the presence of both An. philippinensis and An. nivipes in the north-eastern region of India and the involvement of An. nivipes in transmitting P. falciparum in this area.


Assuntos
Anopheles/genética , Insetos Vetores/genética , Malária Falciparum/transmissão , Plasmodium falciparum/genética , Animais , Anopheles/classificação , Anopheles/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Índia , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Reação em Cadeia da Polimerase/métodos , Especificidade da Espécie
15.
Theor Appl Genet ; 109(7): 1468-73, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15278284

RESUMO

Host-plant resistance is the preferred strategy for management of Asian rice gall midge (Orseolia oryzae), a serious pest in many rice-growing countries. The deployment of molecular markers linked to gall midge resistance genes in breeding programmes can accelerate the development of resistant cultivars. In the present study, we have tagged and mapped a dominant gall midge resistance gene, Gm1, from the Oryza sativa cv. W1263 on chromosome 9, using SSR markers. A progeny-tested F2 mapping population derived from the cross W1263/TN1 was used for analysis. To map the gene locus, initially a subset of the F2 mapping population consisting of 20 homozygous resistant and susceptible lines each was screened with 63 parental polymorphic SSR markers. The SSR markers RM316, RM444 and RM219, located on chromosome 9, are linked to Gm1 at genetic distances of 8.0, 4.9 and 5.9 cM, respectively, and flank the gene locus. Further, gene/marker order was also determined. The utility of the co-segregating SSR markers was tested in a backcross population derived from the cross Swarna/W1263//Swarna, and allelic profiles of these markers were analysed in a set of donor rice genotypes possessing Gm1 and in a few gall midge-susceptible, elite rice varieties.


Assuntos
Dípteros/patogenicidade , Oryza/genética , Oryza/parasitologia , Doenças das Plantas/parasitologia , Animais , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Repetições de Microssatélites
16.
Theor Appl Genet ; 109(7): 1399-405, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15252708

RESUMO

Transgenic rice plants, expressing snowdrop lectin [Galanthus nivalis agglutinin (GNA)], obtained by Agrobacterium-mediated genetic transformation, were evaluated for resistance against the insect, the whitebacked planthopper (WBPH). The transgene gna was driven by the phloem-specific, rice-sucrose synthase promoter RSs1, and the bar was driven by the CaMV 35S promoter. In our previous study, the transgenic status of these lines was confirmed by Southern, Northern and Western blot analyses. Both the transgenes, gna and bar, were stably inherited and co-segregated into progenies in T1 to T5 generations. Insect bioassays on transgenic plants revealed the potent entomotoxic effects of GNA on the WBPH. Also, significant decreases were observed in the survival, development and fecundity of the insects fed on transgenic plants. Furthermore, intact GNA was detected in the total proteins of WBPHs fed on these plants. Western blot analysis revealed stable and consistent expression of GNA throughout the growth and development of transgenic plants. Transgenic lines expressing GNA exhibited high-level resistance against the WBPH. As reported earlier, these transgenics also showed substantial resistance against the brown planthopper and green leafhopper.


Assuntos
Galanthus/genética , Insetos/patogenicidade , Lectinas de Ligação a Manose/genética , Oryza/genética , Lectinas de Plantas/genética , Plantas Geneticamente Modificadas , Animais , Imunidade Inata/genética , Oryza/parasitologia , Doenças das Plantas/parasitologia
17.
J Biotechnol ; 111(2): 131-41, 2004 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15219400

RESUMO

Stem borer resistant transgenic parental lines, involved in hybrid rice, were produced by Agrobacterium-mediated gene transfer method. Two pSB111 super-binary vectors containing modified cry1Ab/cry1Ac genes driven by maize ubiquitin promoter, and herbicide resistance gene bar driven by cauliflower mosaic virus 35S promoter were, used in this study. Embryogenic calli after co-cultivation with Agrobacterium were selected on the medium containing phosphinothricin. Southern blot analyses of primary transformants revealed the stable integration of bar, cry1Ab and cry1Ac coding sequences into the genomes of three parental lines with a predominant single copy integration and without any rearrangement of T-DNA. T1 progeny plants disclosed a monogenic pattern (3:1) of transgene segregation as confirmed by molecular analyses. Furthermore, the co-segregation of bar and cry genes in T1 progenies suggested that the transgenes are integrated at a single site in the rice genome. In different primary transformants with alien inbuilt resistance, the levels of cry proteins varied between 0.03 and 0.13% of total soluble proteins. These transgenic lines expressing insecticidal proteins afforded substantial resistance against stem borers. This is the first report of its kind dealing with the introduction of Bacillus thuringiensis (Bt) cry genes into the elite parental lines involved in the development of hybrid rice.


Assuntos
Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Endotoxinas/metabolismo , Melhoramento Genético/métodos , Controle de Insetos/métodos , Insetos/patogenicidade , Oryza/genética , Oryza/parasitologia , Plantas Geneticamente Modificadas/parasitologia , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Quimera/genética , Quimera/parasitologia , Endotoxinas/genética , Proteínas Hemolisinas , Imunidade Inata/genética , Controle Biológico de Vetores/métodos
18.
Mycopathologia ; 156(2): 101-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12733631

RESUMO

Inadequate information about the genetic structure of the polyphagous Rhizoctonia solani has made sheath blight resistance breeding a difficult task. To assess the variability in the Indian populations of sheath blight fungus, 18 isolates were collected from different rice growing regions of India and analyzed for virulence and electrophoretic profiles of 13 isozymes. The virulence spectrum of all 18 isolates was examined on susceptible IR50 and tolerant Swarnadhan varieties, based on which the isolates could be grouped as highly virulent, moderately virulent or avirulent. A total of 11 enzyme systems with 153 electrophoretic phenotypes were applied to characterize the genetic variation among the isolates. Cluster analyses based on isozyme patterns resulted in one major cluster comprising 16 virulent isolates, with two avirulent isolates loosely linked to this at 0.13 similarity. Isozyme systems of esterases (both alpha and beta) and 6-phosphogluconic dehydrogenase could be used to fingerprint the individual isolates.


Assuntos
Oryza , Doenças das Plantas/microbiologia , Rhizoctonia/enzimologia , Rhizoctonia/patogenicidade , Análise por Conglomerados , Índia , Isoenzimas/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo Genético , Rhizoctonia/genética , Virulência
19.
Plant Biotechnol J ; 1(3): 231-40, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-17156035

RESUMO

Agrobacterium-mediated genetic transformation has been optimized in indica rice susceptible to sap-sucking insects, viz., brown planthopper (BPH) and green leafhopper (GLH). Snowdrop lectin gene (gna) from Galanthus nivalis, driven by phloem-specific rice-sucrose-synthase promoter, along with herbicide resistance gene (bar) driven by CaMV 35S promoter, was employed for genetic transformation. Embryogenic calli--after co-cultivation with Agrobacterium strain LBA4404 harbouring Ti plasmid pSB111-bar-gna--were selected on the medium containing phosphinothricin. PCR and Southern blot analyses confirmed the stable integration of both the genes into genomes of transgenic (T0) rice plants. Northern and Western blot analyses revealed the expression of gna in the transgenic plants. In the T1 and T2 generations, the gna and bar transgenes showed co-segregation at a ratio of 3 : 1. Plant progenies expressing gna, in T1 and T2, exhibited substantial resistance against BPH and GLH pests. This is the first report dealing with transgenic indica rice exhibiting high resistance to both insects.

20.
Endeavour ; 24(4): 157-64, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11196987

RESUMO

Astronomical techniques, calendars and devices were developed independently in many places around the world. However, there was much cross-cultural exchange of technology over the centuries. The cultures of Egypt, Greece, India and China influenced each others' astronomy and each cannot be treated in isolation.


Assuntos
Astronomia/história , China , Antigo Egito , Grécia Antiga , História Antiga , Índia
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