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1.
Environ Entomol ; 46(3): 565-578, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472369

RESUMO

Concern over declining pollinators has led to multiple conservation initiatives for improving forage for bees in agroecosystems. Using data available through the Pollinator Library (npwrc.usgs.gov/pollinator/), we summarize plant-pollinator interaction data collected from 2012-2015 on lands managed by the U.S. Fish and Wildlife Service and private lands enrolled in U.S. Department of Agriculture conservation programs in eastern North Dakota (ND). Furthermore, we demonstrate how plant-pollinator interaction data from the Pollinator Library and seed cost information can be used to evaluate hypothetical seeding mixes for pollinator habitat enhancements. We summarize records of 314 wild bee and 849 honey bee (Apis mellifera L.) interactions detected on 63 different plant species. The wild bee observations consisted of 46 species, 15 genera, and 5 families. Over 54% of all wild bee observations were represented by three genera-Bombus, Lassioglossum, and Melissodes. The most commonly visited forbs by wild bees were Monarda fistulosa, Sonchus arvensis, and Zizia aurea. The most commonly visited forbs by A. mellifera were Cirsium arvense, Melilotus officinalis, and Medicago sativa. Among all interactions, 13% of A. mellifera and 77% of wild bee observations were made on plants native to ND. Our seed mix evaluation shows that mixes may often need to be tailored to meet the unique needs of wild bees and managed honey bees in agricultural landscapes. Our evaluation also demonstrates the importance of incorporating both biologic and economic information when attempting to design cost-effective seeding mixes for supporting pollinators in a critically important part of the United States.


Assuntos
Agricultura/métodos , Abelhas/fisiologia , Conservação dos Recursos Naturais , Polinização , Animais , North Dakota , Especificidade da Espécie
2.
Environ Entomol ; 46(1): 38-49, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062536

RESUMO

Taxonomic identification of pollen has historically been accomplished via light microscopy but requires specialized knowledge and reference collections, particularly when identification to lower taxonomic levels is necessary. Recently, next-generation sequencing technology has been used as a cost-effective alternative for identifying bee-collected pollen; however, this novel approach has not been tested on a spatially or temporally robust number of pollen samples. Here, we compare pollen identification results derived from light microscopy and DNA sequencing techniques with samples collected from honey bee colonies embedded within a gradient of intensive agricultural landscapes in the Northern Great Plains throughout the 2010-2011 growing seasons. We demonstrate that at all taxonomic levels, DNA sequencing was able to discern a greater number of taxa, and was particularly useful for the identification of infrequently detected species. Importantly, substantial phenological overlap did occur for commonly detected taxa using either technique, suggesting that DNA sequencing is an appropriate, and enhancing, substitutive technique for accurately capturing the breadth of bee-collected species of pollen present across agricultural landscapes. We also show that honey bees located in high and low intensity agricultural settings forage on dissimilar plants, though with overlap of the most abundantly collected pollen taxa. We highlight practical applications of utilizing sequencing technology, including addressing ecological issues surrounding land use, climate change, importance of taxa relative to abundance, and evaluating the impact of conservation program habitat enhancement efforts.


Assuntos
Abelhas/fisiologia , Código de Barras de DNA Taxonômico , Magnoliopsida/classificação , Microscopia , Pólen/classificação , Animais , Fazendas , Espécies Introduzidas , North Dakota
3.
BMJ Open ; 6(11): e011768, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27881521

RESUMO

OBJECTIVES: Famine exposure in utero can 'programme' an individual towards type 2 diabetes and obesity in later life. We sought to identify, (1) whether Bangladeshis exposed to famine during developmental life are programmed towards diabetes and obesity, (2) whether this programming was specific to gestational or postnatal exposure windows and (3) whether epigenetic differences were associated with famine exposure. DESIGN: A historical cohort study was performed as part of a wider cross-sectional survey. Exposure to famine was defined through birth date and historical records and participants were selected according to: (A) exposure to famine in postnatal life, (B) exposure to famine during gestation and (C) unexposed. SETTING: Matlab, a rural area in the Chittagong division of Bangladesh. PARTICIPANTS: Young adult men and women (n=190) recruited to a historical cohort study with a randomised subsample included in an epigenetic study (n=143). OUTCOME MEASURES: Primary outcome measures of weight, body mass index and oral glucose tolerance tests (0 and 120 min glucose). Secondary outcome measures included DNA methylation using genome-wide and targeted analysis of metastable epialleles sensitive to maternal nutrition. RESULTS: More young adults exposed to famine in gestation were underweight than those postnatally exposed or unexposed. In contrast, more young adults exposed to famine postnatally were overweight compared to those gestationally exposed or unexposed. Underweight adults exposed to famine in gestation in utero were hyperglycaemic following a glucose tolerance test, and those exposed postnatally had elevated fasting glucose, compared to those unexposed. Significant differences in DNA methylation at seven metastable epialleles (VTRNA2-1, PAX8, PRDM-9, near ZFP57, near BOLA, EXD3) known to vary with gestational famine exposure were identified. CONCLUSIONS: Famine exposure in developmental life programmed Bangladeshi offspring towards diabetes and obesity in adulthood but gestational and postnatal windows of exposure had variable effects on phenotype. DNA methylation differences were replicated at previously identified metastable epialleles sensitive to periconceptual famine exposure.


Assuntos
Metilação de DNA , Diabetes Mellitus Tipo 2/epidemiologia , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/epidemiologia , Inanição , Adulto , Bangladesh , Índice de Massa Corporal , Peso Corporal , Estudos Transversais , Feminino , Estudo de Associação Genômica Ampla , Teste de Tolerância a Glucose , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Análise de Regressão , População Rural
4.
ECS Trans ; 41(41): 207-214, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-31007829

RESUMO

Solid electrolyte interphase (SEI) formation in lithium ion cells prepared with advanced electrolytes is investigated by solid state multinuclear (7Li, 19F, 31P) magnetic resonance (NMR) measurements of electrode materials harvested from cycled cells subjected to an accelerated aging protocol. The electrolyte composition is varied to include the addition of fluorinated carbonates and triphenyl phosphate (TPP, a flame retardant). In addition to species associated with LiPF6 decomposition, cathode NMR spectra are characterized by the presence of compounds originating from the TPP additive. Substantial amounts of LiF are observed in the anodes as well as compounds originating from the fluorinated carbonates.

5.
Nutr Metab Cardiovasc Dis ; 21(7): 476-84, 2011 07.
Artigo em Inglês | MEDLINE | ID: mdl-20227263

RESUMO

BACKGROUND AND AIMS: IL-18 expression is up-regulated in atherosclerotic plaques, and higher levels are seen in obese and Type 2 Diabetic individuals. More recently, a possible role for IL-18 in glucose and energy homeostasis has been suggested. METHODS AND RESULTS: We investigated variation within the IL18 gene and its association with measures of obesity and the metabolic syndrome. Five IL18 tagging single nucleotide polymorphisms (rs1946519, rs2043055, rs549908, rs360729, rs3882891) were selected and genotyped in the Gene-Diet Attica Investigation on childhood obesity (GENDAI) (age range 10-14 yrs); in young European men in the second European Atherosclerosis Research offspring Study (EARSII), an offspring study (age range 18-28 yrs) and in a group of healthy women from the Greek Obese Women study (GrOW) (age range 18-74 yrs). Six common haplotypes were observed. In GrOW, Hap6 (Frequency-2.6%) was associated with higher insulin levels (p<0.0001), estimates of HOMA(-Insulin Resistance) (p<0.0001) and HOMA(-ß-cell) (p<0.0001) compared to the common haplotype Hap1 (Frequency-33.2%). In EARSII, rs2043055 was associated with peak and area under the curve triglycerides (p=0.001 and p=0.002, respectively) after an oral fat tolerance test in 'cases' but not 'controls'. None of the haplotypes were associated with measures of body fatness in any of the studies. CONCLUSION: Association of IL18 variation with insulin levels and estimates of insulin resistance were only observed in our adult study, suggesting that the effects of IL-18 are only associated with increasing age. Taken together with the association of IL18 variants with post-prandial measures, this provides support for IL-18 as a metabolic factor.


Assuntos
Resistência à Insulina/genética , Insulina/sangue , Interleucina-18/genética , Síndrome Metabólica/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Criança , Europa (Continente) , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Grécia , Humanos , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Obesidade/sangue , Período Pós-Prandial , Triglicerídeos/sangue , Adulto Jovem
6.
Eval Rev ; 34(3): 159-84, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20479211

RESUMO

OBJECTIVES: Establish metric properties of the Neighborhood Inventory for Environmental Typology (NIfETy). METHOD: A total of 919 residential block faces were assessed by paired raters using the NIfETy. Reliability was evaluated via interrater and internal consistency reliability; validity by comparing NIfETy data with youth self-reported violence, alcohol, and other drug exposure and crime statistics. RESULTS: Validity and reliability metrics were moderate to exemplary for the total scale and subscales. NIfETy data correlated strongly with crime data and youth self-reported exposure. CONCLUSIONS: The NIfETy is valid and reliable. Future investigations will explore its use in other urban centers and association to other health outcomes.


Assuntos
Características de Residência , Fumar , Meio Social , Transtornos Relacionados ao Uso de Substâncias , Violência , Adolescente , Baltimore , Feminino , Humanos , Estudos Longitudinais , Masculino , Inquéritos e Questionários/normas , Adulto Jovem
7.
Nutr Metab Cardiovasc Dis ; 20(1): 26-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19403283

RESUMO

BACKGROUND AND AIMS: Studies have consistently demonstrated that variants in a number of candidate genes are significant determinants of lipid levels in adults. However, few studies have investigated the impact of these variants in children. Therefore, in the present investigation we examined the influence of ten common variants in the genes for lipoprotein lipase (LPL-S447X), cholesterol ester transfer protein (CETP-Taq1B) apolipoprotein (APO) E (epsilon2, epsilon3, epsilon4), APOA5 (-1131C>T and S19W), APOA4 (S347T) and APOC3 (-482C>T; 1100C>T and 3238G>C) on lipoprotein levels children from the Gene-Diet Attica Investigation on childhood obesity (GENDAI). METHODS AND RESULTS: The ten variants selected were genotyped in 882 Greek children, mean age: 11.2+/-0.7 years (418 females and 464 males). Genotypes were assessed using TaqMan technology. Significantly higher total cholesterol (TC) (p=0.0001) and low-density lipoprotein cholesterol (LDL-C) (p<0.0001) were observed in APOE epsilon4 carriers compared to epsilon3/epsilon3 homozygotes and epsilon2 carriers. The association of APOE genotype with TC and high-density lipoprotein cholesterol (HDL-C) ratio (p=0.0008) was further modulated by body mass index. Carriers of the CETP TaqIB B2 allele had significantly higher HDL-C (p<0.0001) and significantly lower TC: HDL-C ratio (p<0.0001) compared to B1/B1 individuals. No significant associations were observed between APOA4, APOA5 and APOC3 variants and serum lipids. CONCLUSION: This study demonstrates that these common variants are associated with lipid levels in this healthy paediatric cohort, suggesting that even in these young children there may be potential in predicting their lifelong exposure to an adverse lipid profile.


Assuntos
Apolipoproteínas E/genética , Proteínas de Transferência de Ésteres de Colesterol/genética , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Colesterol/sangue , Hipercolesterolemia/genética , Lipase Lipoproteica/genética , Apolipoproteína C-III/genética , Apolipoproteínas A/genética , Índice de Massa Corporal , Criança , Colesterol/genética , HDL-Colesterol/genética , LDL-Colesterol/genética , Estudos de Coortes , Feminino , Estudos de Associação Genética , Grécia , Heterozigoto , Homozigoto , Humanos , Hipercolesterolemia/sangue , Masculino , Polimorfismo de Nucleotídeo Único , Estatística como Assunto
8.
Prev Sci ; 9(4): 245-55, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18931911

RESUMO

There are limited validated quantitative assessment methods to measure features of the built and social environment that might form the basis for environmental preventive interventions. This study describes a model approach for epidemiologic assessment of suspected environmental determinants of violence, alcohol and other drug (VAOD) exposure and fills this gap in current research. The investigation sought to test the feasibility of a systematic and longitudinal assessment of residential block characteristics related to physical and social disorder and indicators of VAOD exposure. Planometric data were used to establish a stratified random sample of street segments within defined neighborhoods of an urban metropolitan area. Field rater assessments of these neighborhood street segments were conducted using the Neighborhood Inventory for Environmental Typology (NIfETy). This report provides a detailed description of the NIfETy Method, including metric properties of the NIfETy Instrument and outcomes of training procedures and quality control measures. Also presented are block-level characteristics and estimates of observable signs of VAOD activity. This work is a first step toward developing future community-level environmental preventive interventions geared to reduce community VAOD exposure among youthful urban populations and may prove to be useful to other public health research groups as well.


Assuntos
Avaliação das Necessidades , Vigilância da População , Características de Residência , Violência/tendências , Adolescente , Adulto , Alcoolismo/epidemiologia , Baltimore/epidemiologia , Estudos de Viabilidade , Humanos , Meio Social , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , População Urbana , Violência/prevenção & controle , Adulto Jovem
9.
Br J Cancer ; 98(3): 571-9, 2008 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-18195709

RESUMO

BORIS (for brother of the regulator of imprinted sites), a paralogue of the transcription factor, CTCF, is a novel member of the cancer-testis antigen family. The aims of the present study were as follows: (1) to investigate BORIS expression in breast cells and tumours using immunohistochemical staining, western and real-time RT-PCR analyses and (2) assess potential correlation between BORIS levels in tumours with clinical/pathological parameters. BORIS was detected in all 18 inspected breast cell lines, but not in a primary normal breast cell culture. In 70.7% (41 of 58 cases) BORIS was observed in breast tumours. High levels of BORIS correlated with high levels of progesterone receptor (PR) and oestrogen receptor (ER). The link between BORIS and PR/ER was further confirmed by the ability of BORIS to activate the promoters of the PR and ER genes in the reporter assays. Detection of BORIS in a high proportion of breast cancer patients implies potential practical applications of BORIS as a molecular biomarker of breast cancer. This may be important for diagnosis of the condition and for the therapeutic use of BORIS. The ability of BORIS to activate promoters of the RP and ER genes points towards possible involvement of BORIS in the establishment, progression and maintenance of breast tumours.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Ligação a DNA/metabolismo , Biomarcadores Tumorais/análise , Mama/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Proteínas de Ligação a DNA/genética , Expressão Gênica , Humanos , Imuno-Histoquímica , Regiões Promotoras Genéticas , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
10.
J Oral Pathol Med ; 35(6): 332-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16762013

RESUMO

BACKGROUND: There is considerable variation in the clinical presentation, behaviour and radiological appearance of central giant cell granulomas (CGCGs), for which multiple treatment modalities have been suggested. METHOD: A 10-year retrospective review of the clinical presentation, radiological features and treatment received was undertaken. RESULTS: The cohort of patients included six males and three females, with an age range of 7-61 years. Six lesions were in the mandible and three in the maxilla. Eight lesions presented with swelling, three in relation to teeth. One case was an incidental finding. Six cases were confined within the cortical plates, one involved soft tissue. Radiological presentation was diverse, but within the existing confines of CGCGs. With one exception, primary treatment was surgical resection with excisional curettage of the remaining bone; to date, none have recurred. CONCLUSION: Diagnosis relies on correct interpretation of clinical, radiographical and histopathological data. Alternative treatments are worthy of consideration, although surgical excision remains the treatment of choice.


Assuntos
Granuloma de Células Gigantes/patologia , Doenças Maxilomandibulares/patologia , Adolescente , Adulto , Criança , Feminino , Granuloma de Células Gigantes/diagnóstico por imagem , Granuloma de Células Gigantes/cirurgia , Hospitais de Distrito , Humanos , Doenças Maxilomandibulares/diagnóstico por imagem , Doenças Maxilomandibulares/cirurgia , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos
11.
Clin Exp Pharmacol Physiol ; 31(12): 885-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15659054

RESUMO

1. Our aim is to measure near-membrane Ca(2+) flux within the presynaptic terminals of central neurons by modifying new genetically encoded Ca(2+) sensors to develop tools capable of measuring localized Ca(2+) signals. 2. We used standard recombinant DNA technologies to generate the DNA coding for a fusion construct of a modified fluorescent 'pericam' Ca(2+) biosensor with a presynaptic P2X7 receptor (P2X7R). The Ca(2+) sensitivity of the biosensor was modified by rational site-directed mutagenesis of the calmodulin portion of the pericam. 3. Biosensor-receptor fusions were transfected into expression systems for evaluation. Expression studies in HEK-293 cells showed that biosensor-receptor fusion construct-delivered protein was localized exclusively to the plasma membrane, confirming that fusion did not affect the ability of the receptor to undergo normal protein synthesis and trafficking. 4. The Ca(2+)-dependent fluorescence of the pericam portion of the fusion protein was also retained. Site-direct mutagenesis within the calmodulin moiety of the pericam significantly reduced the Ca(2+) affinity of the complex. The dynamic range of the sensor following this modification is better matched to the higher Ca(2+) levels expected within presynaptic Ca(2+) microdomains.


Assuntos
Técnicas Biossensoriais/métodos , Cálcio/análise , Membrana Celular/química , Terminações Pré-Sinápticas/química , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Membrana Celular/metabolismo , Humanos , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/fisiologia
12.
J Autoimmun ; 21(3): 195-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14599844

RESUMO

Human autoimmune diseases are a class of complex immune system disorders characterized by loss of tolerance to self-antigens. HLA class II molecules play a central role in the initiation, propagation and prolongation of the disease process. HLA class II transgenic mice with mouse endogenous class II gene Ab knockout were used successfully in several mouse models for human autoimmune diseases, such as IDDM, SLE and EAE in our Lab. However, these mice carry the functional mouse Eb gene from the Abeta(0/0) construct and could express Ebeta/DRalpha(Ealpha) molecules and shape the T cell repertoire in these mice. Recently, we have obtained the new MHCII(Delta/Delta) mice that are devoid of all endogenous conventional mouse MHC class II genes. When these mice are mated with our HLA class II transgenic mice, only human class II genes are expressed. The DR and DQ molecules expressed in these mice shape the T cell repertoire and regulate the immune response. Therefore, this new class of HLA transgenic mice is the first to be completely "humanized" in their MHC class II genes and will be an invaluable mouse model for human MHC class II associated autoimmune diseases.


Assuntos
Deleção de Genes , Genes MHC da Classe II/genética , Antígenos HLA-DQ/imunologia , Antígeno HLA-DR2/imunologia , Animais , Apresentação de Antígeno , Antígenos de Bactérias/farmacologia , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Contagem de Células , Técnicas de Cocultura , Colágeno/química , Enterotoxinas/farmacologia , Citometria de Fluxo , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/metabolismo , Antígeno HLA-DR2/genética , Antígeno HLA-DR2/metabolismo , Humanos , Antígenos Comuns de Leucócito/análise , Linfonodos/citologia , Ativação Linfocitária/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/farmacologia , Receptores de Antígenos de Linfócitos T alfa-beta/química , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Baço/citologia , Timo/citologia , Vacinação
13.
Tissue Antigens ; 62(2): 149-61, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12889995

RESUMO

H2-M or HLA-DM are non-classical class II molecules encoded by the MHC and play an important role during antigen presentation. They catalyze exchange of CLIP (Class II-associated invariant chain peptide) or other low-affinity peptides bound to class II molecules for peptides capable of more efficient binding. The phenotype of mice lacking H2-M is determined by the allotype of the MHC class II molecules expressed. In general, H2-M deficiency does not affect the surface expression of mature class II molecules. The class II molecules in such cases predominantly contain CLIP in their peptide-binding groove. In some mice strains, H2-M deficiency results in defective CD4+ T-cell development accompanied by defective responses to conventional antigens and superantigens. Even though the HLA class II molecules show similar dependency for HLA-DM for presenting antigens in vitro, their interaction in vivo is not known. By using transgenic approach we show here that DQ8 and DR3 are expressed at normal levels in H2-M-deficient mice and the CD4+ T-cell development is unaltered. However, the ability of DQ8 molecules to present peptide antigens is compromised in a H2-M-deficient state. Presentation of exogenous bacterial superantigens by both DQ8 and DR3 is unaffected in H2-M-deficient mice. Unexpectedly, Staphylococcal Enterotoxin B-induced systemic IFN-gamma production was significantly higher in H2-M-deficient DQ8/DR3 transgenic mice and these mice were susceptible to SEB-induced toxic shock at doses that are non-lethal to H2-M-sufficient counterparts.


Assuntos
Antígenos HLA-DQ/genética , Antígeno HLA-DR3/genética , Antígenos de Histocompatibilidade Classe II/genética , Animais , Antígenos/imunologia , Divisão Celular/imunologia , Enterotoxinas/imunologia , Antígenos HLA-DQ/imunologia , Antígenos HLA-DQ/fisiologia , Antígeno HLA-DR3/imunologia , Antígeno HLA-DR3/fisiologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Peptídeos/genética , Peptídeos/imunologia , Peptídeos/fisiologia , Choque Séptico/imunologia , Superantígenos/imunologia , Linfócitos T/imunologia , Linfócitos T/fisiologia
14.
Curr Pharm Biotechnol ; 3(2): 99-115, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12022262

RESUMO

Proteins and peptides that form membrane-spanning pores and channels comprise a diverse class of molecules ranging from short peptides that are unregulated and create non-selective pathways to large ion channel proteins that are highly regulated and exhibit exquisite selectivity for particular ions. The diversity of regulation and selectivity, together with recent advances in protein "re-engineering" technology, provide a strong framework on which to build custom molecules with wide-ranging biotechnological application. Here we review a selection of pore-forming peptides and proteins from a number of different species to highlight their structural and functional diversity. The current and potential uses of native and re-engineered molecules are discussed together with a novel strategy to re-engineer alpha-hemolysin to create targeted and regulable cell-killing agents termed proimmunolysins. Numerous pore-forming peptides are currently in development as antimicrobial agents with potential application as anti-tumorigenic agents. In addition to their roles as biotherapeutic agents, pore-forming proteins are also being developed as biosensors for a range of different analytes. Recent examples of this technology include the use of alpha-hemolysin with an adapter molecule to create sensors for organic molecules and gramicidin as a general-purpose sensor for a range of analytes. These approaches promise to deliver a configurable binding site for analytes encoded in a readily measured electrical signal. The number of applications for pore-forming molecules is sure to grow in both quantity and diversity with increased knowledge of the fundamental structure and function of pores.


Assuntos
Biotecnologia/métodos , Porinas/química , Animais , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Humanos , Porinas/metabolismo , Canais de Ânion Dependentes de Voltagem
15.
FEBS Lett ; 512(1-3): 43-6, 2002 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-11852049

RESUMO

Residues considered essential for ATP binding to the human P2X(7) receptor (hP2X(7)R) were investigated. HEK293 cells or Xenopus oocytes were transfected with wild-type or site-directed mutants of hP2X(7)R constructs and channel/pore activity measured in the presence of ATP or 2',3'-O-(4-benzoylbenzoyl)-ATP (BzATP). Barium uptake and ethidium influx into HEK293 cells were abolished in cells expressing K193A and K311A mutants, and were partially reduced in cells expressing mutant P210A. K193A and K311A mutations also completely abolished responses to ATP and BzATP in Xenopus oocytes as measured by electrophysiology. These results indicate that K193 and K311 are essential residues in ATP binding in the hP2X(7)R.


Assuntos
Trifosfato de Adenosina/metabolismo , Receptores Purinérgicos P2/metabolismo , Bário/metabolismo , Etídio/metabolismo , Humanos , Mutação Puntual , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2X7 , Proteínas Recombinantes/metabolismo
16.
J Allergy Clin Immunol ; 108(5): 764-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11692102

RESUMO

BACKGROUND: Airway inflammation is central to the pathogenesis of allergic asthma, and molecules that mediate this process obviously represent targets for therapy. OBJECTIVE: To study the role of CD4(+) T cells and/or HLA-DQ molecules in allergic asthma, we have generated and characterized models of short ragweed allergen (SRW)-induced inflammation using transgenic mice with HLA-DQ (DQ6 or DQ8), human CD4 (hCD4), or both on a genetic background that lacks mouse MHC II and CD4 (Abeta(0)/mCD4(0)). METHODS: Mice were actively sensitized and later challenged intranasally with SRW allergenic extract. Bronchoalveolar lavage fluid composition, airway inflammation and hyperresponsiveness, blood eosinophil levels, and cell proliferation were examined. RESULTS: In response to SRW treatment, both DQ6 and DQ8 transgenic mice expressing hCD4 developed pulmonary eosinophilia and associated lung tissue damage with increase in eosinophil peroxidase and T(H)2 cytokines in bronchoalveolar lavage fluid, strong airway hyperreactivity, and persistent blood eosinophilia. The response was independent of mast cells/histamine pathway and was mediated by DQ-restricted hCD4(+) T cells. Interestingly, lungs of CD4-deficient DQ6 transgenic mice showed an eosinophilic inflammation without local increase in cytokines and eosinophil peroxidase. The allergic reaction was absent in double-knockout mice and mice expressing either DQ8 or hCD4 alone. CONCLUSIONS: DQ6 molecules are critical to SRW-induced allergy and can operate in the presence or absence of CD4. However, both DQ antigens and CD4 molecules are critical for full manifestation of allergen-induced asthma in transgenic mice.


Assuntos
Asma/imunologia , Hiper-Reatividade Brônquica/imunologia , Antígenos CD4/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/fisiologia , Eosinofilia Pulmonar/imunologia , Alérgenos/imunologia , Animais , Anticorpos Monoclonais/imunologia , Asma/patologia , Líquido da Lavagem Broncoalveolar/imunologia , Antígenos CD4/fisiologia , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Antígenos HLA-DQ/imunologia , Imunoglobulina E/sangue , Pulmão/patologia , Pulmão/fisiopatologia , Ativação Linfocitária , Mastócitos/citologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Pólen/imunologia , Eosinofilia Pulmonar/sangue , Eosinofilia Pulmonar/patologia
17.
J Child Psychol Psychiatry ; 42(7): 915-20, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11693586

RESUMO

It is difficult to study the contribution of fathers' antisocial behaviour to children's development because fathers with behavioural problems are often absent or reluctant to participate in research. This study examines whether mothers' reports about their children's fathers' antisocial behaviour can be substituted for interviews with fathers. Both members of 67 couples (N = 134) were interviewed separately and independently about the men's lifetime antisocial behaviour. There was strong relative agreement: the women's reports about men's antisocial behaviour and the men's self-reports about the same behaviour were highly correlated. However, there was poor agreement about absolute level: compared to men's self-reports, women reported fewer of the men's antisocial behaviours. Women's reports provide a reliable index of men's relative standing in a distribution and can be used in research about their children's fathers, but should not be used to make diagnostic decisions about men's antisocial disorders.


Assuntos
Transtorno da Personalidade Antissocial/diagnóstico , Pai/psicologia , Mães/psicologia , Autorrevelação , Adolescente , Adulto , Transtorno da Personalidade Antissocial/psicologia , Criança , Estudos de Coortes , Análise Fatorial , Família/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Reino Unido
18.
Reg Anesth Pain Med ; 26(3): 215-22, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11359220

RESUMO

BACKGROUND AND OBJECTIVES: Epidural anesthesia (EA) is known to reduce postoperative thromboembolic complications, but mechanisms are incompletely understood. In this study, we tested the hypothesis that local anesthetics (LA) prevent postoperative hypercoagulability without affecting physiologic aggregation and coagulation processes. METHODS: Clot signature analysis (CSA) was used to assess platelet and clotting function. Venous blood samples were collected pre- and postoperatively from 41 patients undergoing major orthopedic surgery. The effect of surgery on 3 CSA parameters (platelet-mediated hemostasis time [PHT], clotting time [CT], and collagen-induced thrombus formation [CITF]) was determined in patients receiving EA (n = 20) and those receiving general anesthesia (GA) (n = 21). RESULTS: In the GA group, orthopedic surgery induced a hypercoagulable state: PHT was reduced by 39% +/- 8.6% (P <.001), CT by 21% +/- 3.3% (P <.001), CITF by 10.3% +/- 5.9% (P =.06) compared with respective baseline values. In the EA group, by contrast, no parameter was altered significantly, but PHT showed a tendency towards prolongation by 33.2% +/- 15.4% (P =.25). CT changed by 0% +/- 4.4% (P =.89), CITF by 3.8% +/- 7% (P =.78). CONCLUSIONS: Use of EA prevents immediate postoperative hypercoagulability without affecting physiologic aggregation and coagulation processes. Also, CSA appears useful in predicting hypercoagulability and detecting platelet dysfunction. Reg Anesth Pain Med 2001;26:215-222.


Assuntos
Anestesia Epidural , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Tromboembolia/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes de Coagulação Sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tromboembolia/sangue , Tromboembolia/etiologia
19.
Clin Exp Pharmacol Physiol ; 27(9): 738-44, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10972543

RESUMO

1. Understanding the regulation of calcium (Ca2+), the most common of the mineral ions within the human body, has always been of extreme interest to physiologists. While the importance of Ca2+ in contributing to physiological events through regulation of levels has been significantly established, seldom is consideration given to the intricacies of this ion and its mechanics in producing such diverse physiological responses in different regions of the cell. 2. The present review will summarize new methodologies used in our laboratories for the study of two major intracellular organelles, mitochondria and the nucleus. These techniques are based predominantly on the use of molecular biological approaches to both create and then target protein-based sensor molecules to specific intracellular locations. 3. The regulation of Ca2+ in the mitochondria and nucleus is of particular interest to us because of the central involvement of these organelles in: (i) cardiac cell responses during ischaemia/reperfusion; and (ii) the control of gene expression, respectively.


Assuntos
Técnicas Biossensoriais , Cálcio/fisiologia , Núcleo Celular/fisiologia , Mitocôndrias/fisiologia , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Dados de Sequência Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfecção
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