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1.
Pregnancy Hypertens ; 25: 103-109, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34098522

RESUMO

OBJECTIVES: Preeclampsia is associated with maternal morbidity and mortality during pregnancy, and also an increased cardiovascular disease (CVD) risk later in life. During preeclampsia, alterations in secreted placental factors leading to systemic maternal endothelial dysfunction are evident. However, little is known about the associated endothelial intracellular signaling. STAT3 is a latent cytoplasmic transcription factor involved in endothelial cell differentiation, survival, and angiogenesis. We aimed to test if preeclampsia and preeclampsia-related placental factors could alter serum-induced STAT3(Y705) activation in endothelial cells. Furthermore, if altered serum-induced endothelial STAT3 (Y705) activation is related to post-preeclamptic CVD risk. STUDY DESIGN: HUVECs were used as a model of maternal endothelium. Experiments entailed addition of 20% human pregnancy serum as well as addition of recombinant PlGF, sFLT1 and VEGF-A165a to the cells. MAIN OUTCOME MEASURES: Levels of pSTAT3(Y705) related to STAT3 levels were evaluated by immunoblotting analysis. RESULTS: Our results show that preeclamptic serum induces significantly lower STAT3(Y705) phosphorylation compared with uncomplicated pregnancy serum (P = 0.0089) in endothelial cells. Furthermore, STAT3(Y705) phosphorylation was not changed upon addition of PlGF, sFLT1, or VEGF-A165a together with pregnancy sera compared with sera alone. Finally, sera from women with previous preeclampsia and current hypertension and carotid atherosclerotic plaques show significantly lower STAT3(Y705) phosphorylation capabilities compared with healthy women with previous uncomplicated pregnancies 8-18 years after deliveries (P = 0.029). CONCLUSIONS: Reduction in serum-induced endothelial STAT3(Y705) activation may play an important role in the preeclampsia-associated endothelial dysfunction. Additionally, reduced endothelial STAT3(Y705) phosphorylation may contribute to increased post-preeclamptic CVD risk 8-18 years after delivery.


Assuntos
Placenta/metabolismo , Pré-Eclâmpsia/genética , Fator de Transcrição STAT3/genética , Adulto , Células Endoteliais/metabolismo , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Pré-Eclâmpsia/sangue , Gravidez , Sistema de Registros , Fatores de Risco , Fator de Transcrição STAT3/sangue , Fator A de Crescimento do Endotélio Vascular/sangue
2.
Anim Genet ; 50(6): 569-597, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31568563

RESUMO

The horse reference genome from the Thoroughbred mare Twilight has been available for a decade and, together with advances in genomics technologies, has led to unparalleled developments in equine genomics. At the core of this progress is the continuing improvement of the quality, contiguity and completeness of the reference genome, and its functional annotation. Recent achievements include the release of the next version of the reference genome (EquCab3.0) and generation of a reference sequence for the Y chromosome. Horse satellite-free centromeres provide unique models for mammalian centromere research. Despite extremely low genetic diversity of the Y chromosome, it has been possible to trace patrilines of breeds and pedigrees and show that Y variation was lost in the past approximately 2300 years owing to selective breeding. The high-quality reference genome has led to the development of three different SNP arrays and WGSs of almost 2000 modern individual horses. The collection of WGS of hundreds of ancient horses is unique and not available for any other domestic species. These tools and resources have led to global population studies dissecting the natural history of the species and genetic makeup and ancestry of modern breeds. Most importantly, the available tools and resources, together with the discovery of functional elements, are dissecting molecular causes of a growing number of Mendelian and complex traits. The improved understanding of molecular underpinnings of various traits continues to benefit the health and performance of the horse whereas also serving as a model for complex disease across species.


Assuntos
Cavalos/genética , Animais , Centrômero , Domesticação , Genoma , Cavalos/fisiologia , Masculino , Linhagem , Condicionamento Físico Animal , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Cromossomo Y
3.
Anim Genet ; 50(5): 449-459, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31282588

RESUMO

Eight horse breeds-Hokkaido, Kiso, Misaki, Noma, Taishu, Tokara, Miyako and Yonaguni-are native to Japan. Although Japanese native breeds are believed to have originated from ancient Mongolian horses imported from the Korean Peninsula, the phylogenetic relationships among these breeds are not well elucidated. In the present study, we compared genetic diversity among 32 international horse breeds previously evaluated by the Equine Genetic Diversity Consortium, the eight Japanese native breeds and Japanese Thoroughbreds using genome-wide SNP genotype data. The proportion of polymorphic loci and expected heterozygosity showed that the native Japanese breeds, with the exception of the Hokkaido, have relatively low diversity compared to the other breeds sampled. Phylogenetic and cluster analyses demonstrated relationships among the breeds that largely reflect their geographic distribution in Japan. Based on these data, we suggest that Japanese horses originated from Mongolian horses migrating through the Korean Peninsula. The Japanese Thoroughbreds were distinct from the native breeds, and although they maintain similar overall diversity as Thoroughbreds from outside Japan, they also show evidence of uniqueness relative to the other Thoroughbred samples. This is the first study to place the eight native Japanese breeds and Japanese Thoroughbred in context with an international sample of diverse breeds.


Assuntos
Cavalos/classificação , Cavalos/genética , Polimorfismo de Nucleotídeo Único , Animais , Cruzamento , Análise por Conglomerados , Variação Genética , Estudo de Associação Genômica Ampla , Japão , Filogenia , Análise de Componente Principal
4.
Anim Genet ; 49(6): 564-570, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30311254

RESUMO

The Functional Annotation of Animal Genomes (FAANG) project aims to identify genomic regulatory elements in both sexes across multiple stages of development in domesticated animals. This study represents the first stage of the FAANG project for the horse, Equus caballus. A biobank of 80 tissue samples, two cell lines and six body fluids was created from two adult Thoroughbred mares. Ante-mortem assessments included full physical examinations, lameness, ophthalmologic and neurologic evaluations. Complete blood counts and serum biochemistries were also performed. At necropsy, in addition to tissue samples, aliquots of serum, ethylenediaminetetraacetic acid (EDTA) plasma, heparinized plasma, cerebrospinal fluid, synovial fluid, urine and microbiome samples from all regions of the gastrointestinal and urogenital tracts were collected. Epidermal keratinocytes and dermal fibroblasts were cultured from skin samples. All tissues were grossly and histologically evaluated by a board-certified veterinary pathologist. The results of the clinical and pathological evaluations identified subclinical eosinophilic and lymphocytic infiltration throughout the length of the gastrointestinal tract as well as a mild clinical lameness in both animals. Each sample was cryo-preserved in multiple ways, and nuclei were extracted from selected tissues. These samples represent the first published systemically healthy equine-specific biobank with extensive clinical phenotyping ante- and post-mortem. The tissues in the biobank are intended for community-wide use in the functional annotation of the equine genome. The use of the biobank will improve the quality of the reference annotation and allow all equine researchers to elucidate unknown genomic and epigenomic causes of disease.


Assuntos
Bancos de Espécimes Biológicos , Genômica , Cavalos/genética , Animais , Feminino , Fenótipo
5.
Anim Genet ; 47(5): 534-42, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27226276

RESUMO

High-density genotype data were analyzed in three lines of swine that express substantial variation in sow fertility to uncover regions of the genome potentially influenced during selection for litter size traits. The experimental lines examined include the Nebraska Index Line (NIL), which has been subjected to long-term selection for litter size; a control line derived from the same population that founded NIL; and a commercial Duroc × Hampshire (D × H) population, in which no selection for litter size was practiced. Regions of the genome potentially affected by selection for litter size traits in NIL were determined by multiple lines of evidence, including altered allelic frequency compared to the other lines, loss of heterozygosity and relative extended haplotype homozygosity. Additionally, a genome-wide association study for litter size traits was conducted in a population based on NIL and commercial maternal line genetics. Several genomic regions identified as putative signatures of selection overlapped with QTL for litter size traits. One of these regions, located on SSC2 (13-14 Mb), includes the candidate gene P2X3R, which plays a role in implantation and sustained release of hormones associated with reproductive processes. Sequencing identified synonymous SNPs in P2X3R that are fixed in NIL but polymorphic with nearly equal frequencies in the D × H line, indicating a potential role of P2X3R in sow fertility. These results suggest that data derived from these lines can help to uncover and understand a portion of the genetic variance associated with fertility traits in swine.


Assuntos
Frequência do Gene , Tamanho da Ninhada de Vivíparos/genética , Seleção Genética , Sus scrofa/genética , Animais , Cruzamento , Mapeamento Cromossômico , Fertilidade/genética , Estudos de Associação Genética , Genética Populacional , Genótipo , Haplótipos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Análise de Sequência de DNA , Sus scrofa/fisiologia
6.
Ann Oncol ; 27(4): 635-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26681674

RESUMO

BACKGROUND: The ability to perform comprehensive profiling of cancers at high resolution is essential for precision medicine. Liquid biopsies using shed exosomes provide high-quality nucleic acids to obtain molecular characterization, which may be especially useful for visceral cancers that are not amenable to routine biopsies. PATIENTS AND METHODS: We isolated shed exosomes in biofluids from three patients with pancreaticobiliary cancers (two pancreatic, one ampullary). We performed comprehensive profiling of exoDNA and exoRNA by whole genome, exome and transcriptome sequencing using the Illumina HiSeq 2500 sequencer. We assessed the feasibility of calling copy number events, detecting mutational signatures and identifying potentially actionable mutations in exoDNA sequencing data, as well as expressed point mutations and gene fusions in exoRNA sequencing data. RESULTS: Whole-exome sequencing resulted in 95%-99% of the target regions covered at a mean depth of 133-490×. Genome-wide copy number profiles, and high estimates of tumor fractions (ranging from 56% to 82%), suggest robust representation of the tumor DNA within the shed exosomal compartment. Multiple actionable mutations, including alterations in NOTCH1 and BRCA2, were found in patient exoDNA samples. Further, RNA sequencing of shed exosomes identified the presence of expressed fusion genes, representing an avenue for elucidation of tumor neoantigens. CONCLUSIONS: We have demonstrated high-resolution profiling of the genomic and transcriptomic landscapes of visceral cancers. A wide range of cancer-derived biomarkers could be detected within the nucleic acid cargo of shed exosomes, including copy number profiles, point mutations, insertions, deletions, gene fusions and mutational signatures. Liquid biopsies using shed exosomes has the potential to be used as a clinical tool for cancer diagnosis, therapeutic stratification and treatment monitoring, precluding the need for direct tumor sampling.


Assuntos
Biomarcadores Tumorais/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Idoso , Biomarcadores Tumorais/biossíntese , Exoma/genética , Exossomos/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Neoplasias/biossíntese , Neoplasias Pancreáticas/patologia
7.
Anim Genet ; 46(4): 381-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26036323

RESUMO

An integral part of functional genomics studies is to assess the enrichment of specific biological terms in lists of genes found to be playing an important role in biological phenomena. Contrasting the observed frequency of annotated terms with those of the background is at the core of overrepresentation analysis (ORA). Gene Ontology (GO) is a means to consistently classify and annotate gene products and has become a mainstay in ORA. Alternatively, Medical Subject Headings (MeSH) offers a comprehensive life science vocabulary including additional categories that are not covered by GO. Although MeSH is applied predominantly in human and model organism research, its full potential in livestock genetics is yet to be explored. In this study, MeSH ORA was evaluated to discern biological properties of identified genes and contrast them with the results obtained from GO enrichment analysis. Three published datasets were employed for this purpose, representing a gene expression study in dairy cattle, the use of SNPs for genome-wide prediction in swine and the identification of genomic regions targeted by selection in horses. We found that several overrepresented MeSH annotations linked to these gene sets share similar concepts with those of GO terms. Moreover, MeSH yielded unique annotations, which are not directly provided by GO terms, suggesting that MeSH has the potential to refine and enrich the representation of biological knowledge. We demonstrated that MeSH can be regarded as another choice of annotation to draw biological inferences from genes identified via experimental analyses. When used in combination with GO terms, our results indicate that MeSH can enhance our functional interpretations for specific biological conditions or the genetic basis of complex traits in livestock species.


Assuntos
Genômica/métodos , Gado/genética , Medical Subject Headings , Terminologia como Assunto , Animais , Bovinos/genética , Cavalos/genética , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Suínos/genética
8.
Heredity (Edinb) ; 106(6): 920-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21048672

RESUMO

Whirling disease, caused by the pathogen Myxobolus cerebralis, leads to skeletal deformation, neurological impairment and under certain conditions, mortality of juvenile salmonid fishes. The disease has impacted the propagation and survival of many salmonid species over six continents, with particularly negative consequences for rainbow trout. To assess the genetic basis of whirling disease resistance in rainbow trout, genome-wide mapping was initiated using a large outbred F(2) rainbow trout family (n=480) and results were confirmed in three additional outbred F(2) families (n=96 per family). A single quantitative trait locus (QTL) region on chromosome Omy9 was identified in the large mapping family and confirmed in all additional families. This region explains 50-86% of the phenotypic variance across families. Therefore, these data establish that a single QTL region is capable of explaining a large percentage of the phenotypic variance contributing to whirling disease resistance. This is the first genetic region discovered that contributes directly to the whirling disease phenotype and the finding moves the field closer to a mechanistic understanding of resistance to this important disease of salmonid fish.


Assuntos
Doenças dos Peixes/genética , Imunidade Inata/genética , Oncorhynchus mykiss/genética , Doenças Parasitárias em Animais/genética , Locos de Características Quantitativas/genética , Alelos , Animais , Mapeamento Cromossômico , Estudos de Associação Genética , Ligação Genética/genética , Genótipo , Myxobolus/fisiologia
9.
J Am Mosq Control Assoc ; 23(2): 187-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17847853

RESUMO

An efficacy study was conducted to evaluate sand granule formulations of Aquaprene (1.8% and 2.8% active ingredient [AI]) and Altosid XR-G (1.5% AI) as a preflood application against Ochlerotatus taeniorhynchus larvae in small field test plots. Aquaprene sand granules (2.8% Al) were applied at 2.5 and 5 lb/acre and the 1.8% AI formulation at 4.2 lb/acre. The 1.8% AI formulation was compared with Altosid XR-G sand granules (1.5% AI) applied at 5 lb/acre. Plots were flooded after 7 days, and 1st and 2nd instars were introduced, pupae were collected, and the plots were drained and dried for 9 days. Assessments were made 21 and 35 days posttreatment. Both Aquaprene sand granules formulations exhibited excellent control throughout the 35-day study.


Assuntos
Hormônios Juvenis , Metoprene , Ochlerotatus , Animais , Desastres , Inseticidas/farmacologia , Larva , Controle de Mosquitos/métodos , Dióxido de Silício
10.
J Am Mosq Control Assoc ; 22(1): 119-22, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16646333

RESUMO

Efficacy studies were conducted with Aquaprene emulsifiable concentrate (EC) (33.6% active ingredient [AI]) and wettable powder (WP) (40% AI) (S)-methoprene insect growth regulator formulations against larval Ochlerotatus taeniorhynchus in small field test plots. Aquaprene EC was applied at 7.18 and 9.57 g/acre. Approximately one thousand 4th-stage larvae were added to each plot before treatment, and 24 h later pupae were collected to determine emergence inhibition. At both applications rates, Aquaprene EC was extremely effective (99%) at significantly reducing adult emergence in the studies. Two application rates ((S)-methoprene at 2.4 and 4.8 g/acre) of the Aquaprene WP also were evaluated against Oc. taeniorhynchus at 1, 3, 7, and 14 days after treatment. Emergence inhibition and statistical analysis showed that significant differences were found between the (S)-methoprene rates of 2.4 and 4.8 g/acre at each posttreatment assessment. The (S)-methoprene rate of 4.8 g/acre was effective in controlling adult emergence for up to 14 days after treatment.


Assuntos
Hormônios Juvenis , Controle de Mosquitos/métodos , Ochlerotatus , Animais , Emulsões , Larva , Metoprene , Pós
11.
J Am Mosq Control Assoc ; 20(3): 299-304, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15532931

RESUMO

Arm-in-cage laboratory evaluations of 2 proprietary formulations of the mosquito repellents IR3535 and N,N-diethyl-3-methylbenzamide (deet; aqueous cream, hydroalcoholic spray) were made with 10 and 20% concentrations of each repellent. Also, 4 commercially available products containing IR3535 (Expedition insect repellent 20.07% active ingredient [AI], Bug Guard Plus with SPF30 sunscreen 7.5% AI, Bug Guard Plus with SPF15 sunscreen 7.5% AI, and Bug Guard Plus 7.5% AI) were tested. All comparisons were made on an equal formulation or concentration basis. Eight volunteers tested all formulations or products 3 times against laboratory-reared, Aedes aegypti and Culex quinquefasciatus mosquitoes (6-10 days old). Products were applied to a forearm at the rate of 0.002 g/cm2. The other forearm was not treated and served as a control. Elapsed time to 1st and 2nd consecutive bite was recorded. Mean protection time (i.e., time to 1st bite) with proprietary formulations of IR3535 were comparable to those of deet, with 20% concentrations providing greater protection against Ae. aegypti (3 h) and Cx. quinquefasciatus (6 h). Mean protection time for commercial products containing IR3535 ranged from nearly 90 to 170 min for Ae. aegypti and 3.5 to 6.5 h for Cx. quinquefasciatus. Mean time to the 2nd bite was similar to time to 1st bite for each mosquito species, product, and formulation.


Assuntos
Aedes , Culex , DEET , Mordeduras e Picadas de Insetos/prevenção & controle , Repelentes de Insetos , Propionatos , Aerossóis , Animais , Feminino , Antebraço , Humanos , Masculino , Pomadas
12.
J Am Mosq Control Assoc ; 20(4): 429-33, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15669386

RESUMO

Efficacy studies were conducted with VectoBac 12AS and Teknar HP-D larvicides against 3rd-instar Ochlerotatus taeniorhynchus and Culex quinquefasciatus in small field test plots. The products were obtained off the shelf from distributors and had different lot numbers. They were evaluated over a 2-year period in spring 2002 and 2003. Application rates were 0.29, 0.58, and 1.10 liter/ha and evaluations were made 24 and 48 h after treatment. Both products performed well in these studies, with VectoBac 12AS being more effective at the 0.29 liter/ha rate.


Assuntos
Bacillus thuringiensis , Culex , Ochlerotatus , Controle Biológico de Vetores , Animais , Larva
13.
Nucleic Acids Res ; 29(21): 4472-81, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11691935

RESUMO

DNA photolyases catalyze the blue light-dependent repair of UV light-induced damage in DNA. DNA photolyases are specific for either cyclobutane-type pyrimidine dimers or (6-4) photoproducts. PHR2 is a gene that in Chlamydomonas reinhardtii encodes a class II DNA photolyase which catalyzes the photorepair of cyclobutane-type pyrimidine dimers. Based on amino acid sequence analysis of PHR2, which indicates the presence of a chloroplast targeting sequence, PHR2 was predicted to encode the chloroplast photolyase of Chlamydomonas. Using a sensitive gene-specific in vivo repair assay, we found that overexpression of PHR2 in Chlamydomonas results in targeting of the protein to not only the chloroplast, but also to the nucleus. Overexpression of PHR2 photolyase in a photoreactivation-deficient mutant, phr1, results in a largely inactive product. The phr1 mutant was found to be deficient in both photorepair of a chloroplast gene, rbcL, and a nuclear gene, rDNA. These results suggest that PHR2 is the structural gene for the photolyase targeted to both the chloroplast and the nucleus, and that the PHR1 gene product is necessary for full activity of PHR2 protein. To our knowledge, the requirement for a second gene for full activity of a DNA photolyase is novel.


Assuntos
Apoenzimas/classificação , Apoenzimas/metabolismo , Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/genética , Desoxirribodipirimidina Fotoliase/classificação , Desoxirribodipirimidina Fotoliase/metabolismo , Proteínas Fúngicas , Glicoproteínas de Membrana , Animais , Apoenzimas/genética , Western Blotting , Núcleo Celular/enzimologia , Núcleo Celular/genética , Núcleo Celular/metabolismo , Chlamydomonas reinhardtii/citologia , Chlamydomonas reinhardtii/metabolismo , Cloroplastos/enzimologia , Cloroplastos/genética , Cloroplastos/metabolismo , DNA/genética , DNA/metabolismo , Dano ao DNA/efeitos da radiação , Reparo do DNA/genética , DNA de Cloroplastos/genética , DNA Ribossômico/genética , Desoxirribodipirimidina Fotoliase/genética , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática , Teste de Complementação Genética , Mutação/genética , Fotoquímica , Transporte Proteico , Dímeros de Pirimidina/genética , Dímeros de Pirimidina/metabolismo , Raios Ultravioleta
14.
J Org Chem ; 66(23): 7804-10, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11701039

RESUMO

A new synthetic pathway to the 4,5-diarylphenanthrenes 8 having a helical twist in their structures was developed. The synthetic sequence involves condensation of the diketone 5 with 2 equiv of the lithium acetylides derived from the diacetylenes 4 followed by protonation to produce the propargylic alcohols 6. Reduction of 6 with triethylsilane in the presence of trifluoroacetic acid furnished the tetraacetylenic hydrocarbons 7 in nearly quantitative yields. Treatment of 7 with potassium tert-butoxide under refluxing toluene at 110 degrees C for up to 10 h then furnished the 4,5-diarylphenanthrenes 8. Apparently, the transformation from 7 to 8 involves initial prototropic isomerizations to form the benzannulated enyne-allenes 9. Two subsequent formal intramolecular Diels-Alder reactions via the biradicals 10 and 12 derived from the C(2)-C(6) cyclizations then led to 13, which in turn underwent tautomerizations to give 8. The structure of 8a was established by the X-ray structure analysis, showing that the two phenyl substituents are bent away from each other and the central aromatic system is severely distorted with a helical twist. The existence of a helical twist in 8 imposed by the aryl groups at the 4- and 5-positions was also revealed with a set of AB (1)H NMR signals for the diastereotopic methylene hydrogens on the five-membered rings.

15.
J Org Chem ; 66(20): 6662-8, 2001 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11578218

RESUMO

New synthetic pathways to 11H-benzo[b]fluoren-11-ols, 1H-cyclobut[a]indenes, and related compounds via biradicals generated from benzoenyne-allenes were developed. Treatment of the diacetylenic propargylic alcohols 13, derived from condensation between benzophenones and the lithium acetylide of 1-(2-ethynylphenyl)-2-phenylethyne, with thionyl chloride produced the 11-chloro-11H-benzo[b]fluorene 14 and, after hydrolysis, the corresponding 11H-benzo[b]fluoren-11-ols 15. The transformation involved a sequence of reactions, including a biradical-forming C2-C6 cyclization (Schmittel cyclization) reaction of the chlorinated benzoenyne-allene intermediates followed by an intramolecular radical-radical coupling to form the formal Diels-Alder adducts. Interestingly, in the case of the diacetylenic propargylic alcohol 26, obtained from dibenzosuberenone (25), an intramolecular [2 + 2] cycloaddition reaction of the chlorinated benzoenyne-allene intermediate occurred, furnishing the 1H-cyclobut[a]indene 27 exclusively. The dramatic change of the reaction pathway could be attributed to the emergence of a steric strain due to the nonbonded interactions with the chloro substituent along the pathway toward the formal Diels-Alder adduct 31. On the other hand, the non-chlorinated benzoenyne-allene, derived from prototropic isomerization of the diacetylenic hydrocarbon 60, underwent a formal Diels-Alder reaction to furnish the 11H-benzo[b]fluorene-type hydrocarbon 61 exclusively.

17.
Plant Mol Biol ; 40(6): 1063-71, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10527430

RESUMO

Damage to DNA induced by ultraviolet light can be reversed by a blue light-dependent reaction catalyzed by enzymes called DNA photolyases. Chlamydomonas has been shown to have DNA photolyase activity in both the nucleus and the chloroplast. Here we report the cloning and sequencing of a gene, PHR2, from Chlamydomonas encoding a class II DNA photolyase. The PHR2 protein, when expressed in Escherichia coli, is able to complement a DNA photolyase deficiency. The previously described Chlamydomonas mutant, phr1, which is deficient in nuclear but not chloroplast photolyase activity was shown by RFLP analysis not to be linked to the PHR2 gene. Unlike the recently reported class II DNA photolyase from Arabidopsis, the protein encoded by PHR2 is predicted to contain a chloroplast targeting sequence. This result, together with the RFLP data, suggests that PHR2 encodes the chloroplast targeted DNA photolyase.


Assuntos
Chlamydomonas/genética , Desoxirribodipirimidina Fotoliase/genética , Sequência de Aminoácidos , Animais , Southern Blotting , Chlamydomonas/enzimologia , Clonagem Molecular , DNA/química , DNA/genética , Escherichia coli/genética , Genes/genética , Teste de Complementação Genética , Isoenzimas/genética , Dados de Sequência Molecular , Mutação , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Transcrição Gênica
18.
Am J Trop Med Hyg ; 60(1): 54-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9988322

RESUMO

The Panamanian Ministry of Health, through the Interamerican Development Bank, contracted the Gorgas Memorial Laboratory to conduct epidemiologic studies on leishmaniasis and malaria in eastern Panama from July 1984 through June 1985. Preliminary results of the biomedical and entomologic teams investigating the epidemiology of cutaneous leishmaniasis in the eastern part of the country are presented in this short report. The principal findings of the study revealed 1) a large disparity in the incidence and prevalence of the disease among the five communities investigated; 2) the appearance of self-cures without the benefit of effective treatment; 3) a relatively high percentage of subclinical cases; and 4) determination of the sandfly vector species for each community. Also reported here is a case of a double infection with two distinct species of Leishmania, L. mexicana and L. amazonensis, in a single individual.


Assuntos
Leishmaniose Cutânea/epidemiologia , Adulto , Animais , Antígenos de Protozoários , Feminino , Humanos , Incidência , Insetos Vetores , Leishmania guyanensis/imunologia , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/transmissão , Panamá/epidemiologia , Prevalência , Psychodidae , Testes Cutâneos
19.
Eur J Surg Oncol ; 24(5): 427-30, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9800974

RESUMO

AIMS: To examine the hypothesis that lymphatic dissemination in breast cancer occurs sequentially. METHODS: Thirty patients with clinically localized adenocarcinoma were studied. Patent blue dye was administered into the tumour at the beginning of a modified radical mastectomy or segmental mastectomy with en bloc axillary lymph-node dissection (ALND). In the removed specimen, blue-stained lymphatic channels were dissected from the primary tumour to the first draining lymph node(s) (sentinel node(s)). RESULTS: Identification of a sentinel node (SN) was successful in 26 patients (87%). In 10 patients the SN was tumour-positive. In six of these patients, the SN was the only tumour-positive node. There was no incidence of 'skip' metastasis. CONCLUSIONS: This study confirms the sequential nature of lymphatic dissemination. When confirmed in vivo, these data may lead to a substantial reduction of the need for ALND without compromising survival and regional control and without loss of prognostic and staging information.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Excisão de Linfonodo/métodos , Metástase Linfática/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Corantes , Feminino , Humanos , Linfonodos/patologia , Pessoa de Meia-Idade
20.
J Med Entomol ; 32(6): 888-94, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8551515

RESUMO

The egg of Aedeomyia squamipennis (Lynch Arribalzaga) is described with the aid of scanning electron micrographs. This study allows separation of the eggs of Ad. squamipennis from the eggs of other mosquitoes inhabiting similar aquatic vegetation.


Assuntos
Culicidae/citologia , Óvulo/ultraestrutura , Animais
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