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1.
J Econ Entomol ; 115(6): 1790-1805, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36515109

RESUMO

The fall armyworm (FAW) Spodoptera frugiperda (Smith; Lepidoptera: Noctuidae) is present in over 70 countries in Africa, Asia, and Oceania. Its rapid dispersal since 2016 when it was first reported in western Africa, and associated devastation to agricultural productivity, highlight the challenges posed by this pest. Currently, its management largely relies on insecticide sprays and transgenic Bacillus thuringiensis toxins, therefore understanding their responses to these agents and characteristics of any resistance genes enables adaptive strategies. In Australia, S. frugiperda was reported at the end of January 2020 in northern Queensland and by March 2020, also in northern Western Australia. As an urgent first response we undertook bioassays on two Australian populations, one each from these initial points of establishment. To assist with preliminary sensitivity assessment, two endemic noctuid pest species, Helicoverpa armigera (Hübner; Lepidoptera, Noctuidae) and Spodoptera litura (Fabricius; Lepidoptera, Noctuidae), were concurrently screened to obtain larval LC50 estimates against various insecticides. We characterized known resistance alleles from the VGSC, ACE-1, RyR, and ABCC2 genes to compare with published allele frequencies and bioassay responses from native and invasive S. frugiperda populations. An approximately 10× LC50 difference for indoxacarb was detected between Australian populations, which was approximately 28× higher than that reported from an Indian population. Characterization of ACE-1 and VGSC alleles provided further evidence of multiple introductions in Asia, and multiple pathways involving genetically distinct individuals in Australia. The preliminary bioassay results and resistance allele patterns from invasive S. frugiperda populations suggest multiple introductions have contributed to the pest's spread and challenge the axiom of its rapid 'west-to-east' spread.


Assuntos
Inseticidas , Mariposas , Animais , Spodoptera/genética , Proteínas Hemolisinas/farmacologia , Alelos , Endotoxinas/genética , Resistência a Inseticidas/genética , Proteínas de Bactérias/genética , Austrália , Inseticidas/farmacologia , Larva , Bioensaio , Zea mays/genética
2.
Neurol India ; 68(1): 26-34, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32129239

RESUMO

Over the last decade, research has intensified worldwide on the use of low-temperature plasmas in medicine and healthcare. Researchers have discovered many methods of applying plasmas to living tissues to deactivate pathogens; to end the flow of blood without damaging healthy tissue; to sanitize wounds and accelerate its healing; and to selectively kill malignant cancer cells. This review paper presents the latest development of advanced and plasma-based technologies used for applications in neurology in particular. Institute for Plasma Research (IPR), an aided institute of the Department of Atomic Energy (DAE), has also developed various technologies in some of these areas. One of these is an Atmospheric Pressure Plasma Jet (APPJ). This device is being studied to treat skin diseases, for coagulation of blood at faster rates and its interaction with oral, lung, and brain cancer cells. In certain cases, in-vitro studies have yielded encouraging results and limited in-vivo studies have been initiated. Plasma activated water has been produced in the laboratory for microbial disinfection, with potential applications in the health sector. Recently, plasmonic nanoparticle arrays which allow detection of very low concentrations of chemicals is studied in detail to allow early-stage detection of diseases. IPR has also been developing AI-based software called DeepCXR and AIBacilli for automated, high-speed screening and detection of footprints of tuberculosis (TB) in Chest X-ray images and for recognizing single/multiple TB bacilli in sputum smear test images, respectively. Deep Learning systems are increasingly being used around the world for analyzing electroencephalogram (EEG) signals for emotion recognition, mental workload, and seizure detection.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Tuberculose/diagnóstico por imagem , Tuberculose/cirurgia , Academias e Institutos , Aprendizado Profundo , Humanos , Plasma/diagnóstico por imagem , Análise Espectral Raman/métodos
3.
BMC Biol ; 15(1): 63, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28756777

RESUMO

BACKGROUND: Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests. RESULTS: We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes. CONCLUSIONS: The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant.


Assuntos
Genoma de Inseto , Herbivoria , Mariposas/genética , Animais , Perfilação da Expressão Gênica , Genômica , Espécies Introduzidas , Larva/genética , Larva/crescimento & desenvolvimento , Mariposas/classificação , Mariposas/crescimento & desenvolvimento , Análise de Sequência de DNA
5.
Insect Mol Biol ; 21(4): 437-45, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22708613

RESUMO

Genetic polymorphisms underlying adaptive shifts in thermal responses are poorly known even though studies are providing a detailed understanding of these responses at the cellular and physiological levels. The Frost gene of Drosophila melanogaster is a prime candidate for thermal adaptation; it is up-regulated under cold stress and knockdown of this gene influences cold resistance. Here we describe an amino-acid INDEL polymorphism in proline repeat number in the structural component of this gene. The two main repeats, accounting for more than 90% of alleles in eastern Australia, show a strong clinal pattern; the 6P allele was at a high frequency in tropical locations, and the 10P allele was common in temperate populations. However, the frequency of these alleles was not associated with three different assays of cold resistance. Adult transcription level of Frost was also unrelated to cold resistance as measured through post chill coma mobility. The functional significance of the proline repeat polymorphism therefore remains unclear despite its clinal pattern. The data also demonstrate the feasibility of using Roche/454 sequencing for establishing clinal patterns.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster , Prolina/genética , Sequências Repetitivas de Aminoácidos/genética , Aclimatação/genética , Adaptação Fisiológica/genética , Alelos , Animais , Austrália , Temperatura Baixa , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Polimorfismo Genético
6.
Clin Pharmacol Ther ; 88(6): 814-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20981001

RESUMO

Endoxifen is an active metabolite of tamoxifen, a drug used in the treatment of breast cancer. In order to be clinically effective, tamoxifen must be converted to endoxifen by cytochrome P450 2D6 (CYP2D6). A study involving single escalating oral doses was conducted in humans to evaluate the safety, tolerability, and pharmacokinetics (PK) of endoxifen. This is the first study demonstrating that single oral doses of endoxifen are safe and well tolerated and have sufficient bioavailability to reach systemically effective levels in human subjects. Furthermore, it was found that endoxifen is rapidly absorbed and systemically available and that it displays dose proportionality in peak drug concentrations in plasma (C(max)) and area under the concentration-time curve extrapolated from 0 to ∞ (AUC(0-∞)) over the dose range 0.5-4.0 mg.


Assuntos
Neoplasias da Mama/metabolismo , Tamoxifeno/análogos & derivados , Disponibilidade Biológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Citocromo P-450 CYP2D6/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Tamoxifeno/efeitos adversos , Tamoxifeno/metabolismo , Tamoxifeno/farmacocinética , Tamoxifeno/uso terapêutico
7.
J Biomol Screen ; 4(4): 187-192, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10838438

RESUMO

Identifying potent enzyme inhibitors through a robust HTS assay is currently thought to be the most efficient way of searching for lead molecules. We have developed a HTS assay that mimics a crucial step in an essential metabolic pathway, the purine salvage pathway of the malarial parasite Plasmodium falciparum. In this assay we have used purified recombinant enzymes: hypoxanthine guanine phosphoribosyl transferase (HGPRT) and inosine monophosphate dehydrogenase (IMPDH) from the malarial parasite and the human host, respectively. These two enzymes, which work in tandem, are used to set up a coupled assay that is robust enough to meet the stringent criteria of an HTS assay. In the first phase of our screen we seem to have identified novel inhibitors that kill the parasite by inhibiting the salvage pathway of the parasite.

8.
J Assoc Physicians India ; 42(11): 885-7, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7868492

RESUMO

The study comprised of 2 groups. In group I sickling test was done in students studying in a school which mainly caters to the educational needs of the backward community. Out of 130 students examined 24 were found to be sicklers. The distribution of this cases among various castes/tribes were as follows--Choudharys (Cd)-13, Gamits (Gt)-4, Dhodhia Patels (DP)-4, Koknis (K)-2 and Koli Patel (KP)-1. In group II, patients admitted in the hospital between Jan '81 to June '82 were studied. The prevalence of sickle cell syndrome was 1.74%. The most common mode of presentation were limb pains and weakness. Hemoglobin values ranged from 3.0 gram% to 12 gms%. 35 cases of HbSS, 149 cases of HbAS and 1 case of Sickle Beta thalassemia were seen. The distribution of the cases amongst the various tribes and castes were as follows-Cd-93, Gt-56, DP-23, KP-7, K-4 and Rathods (R)-2. No cases were found in Anavil Brahmins or Patidar Patels. Clinical and pathological observations included palpable splenomegaly in 54 cases, splenic abscess in 1 case, isothenuria in large number of patients, microscopic hematuria in 6 cases and frank hematuria in 1 case. Osteomyelitis and cholecystitis were seen in one case each.


Assuntos
Anemia Falciforme/epidemiologia , Adolescente , Anemia Falciforme/sangue , Anemia Falciforme/etnologia , Criança , Feminino , Hemoglobina Falciforme/análise , Humanos , Índia/epidemiologia , Masculino , Prevalência
9.
Int J Dev Biol ; 37(4): 601-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8180004

RESUMO

Full primitive streak stage chick embryos, cultured in vitro for 20 h in the presence of 10(-9) to 10(-7) moles of retinoic acid (retinol, all-trans), exhibit increasing extent of malformations. RA causes caudalization, suppression of telencephalon, formation of open and enlarged neural tube in the regions of midbrain, hindbrain and spinal cord, failure of fusion of heart tubes, and gives rise to winged or diffused, and even supernumerary somites. Extreme abnormalities include failure to form the head fold and foregut. Abnormal embryos were graded according to Rao and Chauhan (Teratology 4: 191-198, 1971), and we find that the larger the severity of malformation, the smaller the size of total cell population and blastoderm area. Concomitant to caudalization, retinoic acid suppresses the cell population growth.


Assuntos
Anormalidades Induzidas por Medicamentos , Blastoderma/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Tretinoína/toxicidade , Animais , Blastoderma/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Embrião de Galinha , Técnicas de Cultura , Coração/efeitos dos fármacos , Coração/embriologia , Morfogênese/efeitos dos fármacos , Defeitos do Tubo Neural/induzido quimicamente , Telencéfalo/efeitos dos fármacos , Telencéfalo/embriologia , Tretinoína/farmacologia
10.
Indian J Exp Biol ; 31(10): 803-7, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8276431

RESUMO

Four hundred and forty four full primitive streak stage chick embryos were cultured in vitro and 261 were transplanted with 1, 3 or 5 Hensen's nodes in the area opaca. Irrespective of the number of grafts, neural induction was observed in 90% cases. The development of control and grafted embryos and the size of blastoderm area were monitored at the time of grafting and after 20 hr. We find that the induced neural tissue and differentiated tissue of graft-origin neither fuse with the host embryonic axis, nor retard its development.


Assuntos
Embrião de Galinha/embriologia , Animais , Blastoderma/citologia , Transplante de Tecido Fetal , Gástrula/citologia , Tecido Nervoso/transplante , Sistema Nervoso/embriologia
11.
Ear Hear ; 1(4): 223-5, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7409361

RESUMO

A one-half gain rule for hearing aid fitting based on the unaided average hearing threshold level was first proposed by S. F. Lybarger. From records on almost 500 clients with sensorineural loss for whom hearing aids were prescribed and fitted, the functional gain for speech reception threshold, 500 Hz, and the average of 1000 and 2000 Hz was examined. The one-half gain rule was found to be valid for speech reception threshold except with mild hearing losses where the gain obtained was a little less than one-half the unaided hearing threshold level. The one-half gain rule is easily computed and provides a good first-order approximation of operating gain needs.


Assuntos
Auxiliares de Audição/normas , Limiar Auditivo , Perda Auditiva Neurossensorial/psicologia , Perda Auditiva Neurossensorial/reabilitação , Humanos , Prescrições , Percepção da Fala , Teste do Limiar de Recepção da Fala
12.
J Am Audiol Soc ; 3(6): 241-4, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-681195

RESUMO

The preoperative audiometric and electroacoustic impedance test results of 24 surgically confirmed otosclerotics are reviewed with special attention given to the direction of needle deflection during acoustic reflex testing. Information on the direction of needle deflection during acoustic reflex testing was gathered at 5 or 10 dB above reflex threshold. In 12 of the 24 patients acoustic reflexes were present, and in each case the response included negative needle deflections. The presence or absence of the acoustic reflex seemed to be related to the reported duration of the hearing loss.


Assuntos
Testes de Impedância Acústica , Otosclerose/diagnóstico , Estimulação Acústica/métodos , Adolescente , Adulto , Audiometria , Limiar Auditivo , Condução Óssea , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Otosclerose/cirurgia , Fala
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