RESUMEN
In crucifer cytogenomics, BAC contigs of Arabidopsis thaliana have been used as probes for comparative chromosome painting among species. Here we successfully tested chromosome-specific BAC contigs of A. thaliana (n = 5) and A. halleri (n = 8) as probes for reciprocal BAC painting. Furthermore, BAC contigs of both Arabidopsis species were applied as multi-species painting probes to a third crucifer species, Noccaea caerulescens (n = 7), revealing their shared chromosome homeology. Specifically, we found homeology across portions of chromosomes At2, Ah4, and Nc4, which reflects their shared common origin with chromosome AK4 of the Ancestral Crucifer Karyotype (n = 8). We argue that multi-species and multi-directional painting will significantly expedite comparative cytogenomics in Brassicaceae and other plant families.
Asunto(s)
Brassicaceae/genética , Pintura Cromosómica/métodos , Cromosomas Artificiales Bacterianos/genética , Cromosomas de las Plantas/genética , Arabidopsis/clasificación , Arabidopsis/genética , Brassicaceae/clasificación , Hibridación Fluorescente in Situ , Cariotipificación , Especificidad de la EspecieRESUMEN
In July 2008, owners of seasonal camps in Vermont and Maine were exposed to large numbers of questing ticks after opening their camps for the season. Examination of collected specimens revealed that the camp in Vermont was infested with Ixodes cookei Packard, and the camp in Maine was infested with Ixodes marxi Banks. In both instances, numerous tick bites were reported by residents. Both camps were also occupied by wildlife during the off-season, primarily squirrels (Maine) and skunks (Vermont). Subsequent samples from the Vermont site were tested for the presence of Powassan encephalitis virus, though no viral activity was detected.
Asunto(s)
Vivienda , Ixodes , Población Rural , Infestaciones por Garrapatas/epidemiología , Animales , Vectores Arácnidos/clasificación , Vectores Arácnidos/crecimiento & desarrollo , Vectores Arácnidos/virología , Virus de la Encefalitis Transmitidos por Garrapatas/aislamiento & purificación , Encefalitis Transmitida por Garrapatas/transmisión , Femenino , Pisos y Cubiertas de Piso , Humanos , Ixodes/clasificación , Ixodes/crecimiento & desarrollo , Ixodes/virología , Maine/epidemiología , Masculino , Mephitidae , Sciuridae , Estaciones del Año , Vermont/epidemiologíaRESUMEN
Degeneration of the dopaminergic neurons of the substantia nigra pars compacta in Parkinson's disease induces an abnormal activation of the glutamatergic neurotransmission system within the basal ganglia network and related structures. The aim of this study was to use proton MRS to show metabolic changes in the striatum of 6-hydroxydopamine-lesioned rats, a rodent animal model of Parkinson's disease. Animals were examined before and after extensive lesioning of the nigral dopaminergic neurons and after acute administration of L-3,4-dihydroxyphenylalanine. No significant alterations in glutamate concentrations, assessed by the MR signal dominated by glutamate with minor contributions from glutamine and gamma-aminobutyric acid, could be measured. The total choline/total creatine ratio was found to be reduced in the striatum of the ipsilateral hemisphere.
Asunto(s)
Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Espectroscopía de Resonancia Magnética/métodos , Enfermedad de Parkinson/metabolismo , Animales , Humanos , Masculino , Protones , Ratas , Ratas Sprague-DawleyRESUMEN
The phenotype of mosaic variegated aneuploidy (MVA) syndrome is characterized by severe microcephaly, growth deficiency, mental retardation, and mild physical anomalies. The MVA syndrome is associated with mosaicism for several different aneuploidies involving many different chromosomes with or without premature centromere division (PCD). To date 28 cases of MVA syndrome have been reported. We report the first case of MVA syndrome without microcephaly. The clinical features in our patient included craniofacial dysmorphic features, growth retardation, and developmental delay. Cytogenetics analyses and FISH studies showed multiple aneuploidy with trisomy 18, 19, and 8, respectively in blood lymphocyte and fibroblasts without PCD. This case is compared with the other of MVA syndrome previously reported in literature. From this case report, we suggest that microcephaly is not mandatory for the diagnosis of MVA syndrome.
Asunto(s)
Anomalías Múltiples/genética , Aneuploidia , Anomalías Craneofaciales , Discapacidades del Desarrollo/patología , Trastornos del Crecimiento/patología , Anomalías Múltiples/patología , Humanos , Hibridación Fluorescente in Situ , Lactante , Cariotipificación , Masculino , Microcefalia/patología , SíndromeRESUMEN
Human babesiosis in the northeastern United States caused by Babesia microti (Apicomplexa: Piroplasmida) is mainly reported from coastal New England sites, where deer ticks (Ixodes dammini) are common. However, the piroplasm has been detected in microtine rodents elsewhere in association with I. angustus or other nidicolous ticks, suggesting that the agent is widely distributed but zoonotically significant only where a human-biting "bridge" vector is present. To determine whether this piroplasm may be enzootic in areas where I. dammini is absent, we surveyed small mammals collected from 2 sites in Maine, where I. angustus or I. muris is common but I. dammini is not. Of 43 chipmunks, voles, deer mice, and shrews examined, 3 (6.9, 95% confidence interval 0 to 14.5) were parasitemic, as determined by blood smear or polymerase chain reaction targeting a piroplasm-specific portion of the 18S ribosomal DNA gene. Phylogenetic analysis of the sequenced amplification products demonstrates the presence of 2 forms of B. microti. We conclude that B. microti may be enzootic in the absence of I. dammini but that human risk relates to dense infestations of this human-biting tick.
Asunto(s)
Babesia microti/aislamiento & purificación , Babesiosis/veterinaria , Enfermedades de los Roedores/epidemiología , Musarañas/parasitología , Animales , Vectores Arácnidos , Arvicolinae/parasitología , Babesia microti/clasificación , Babesiosis/epidemiología , Babesiosis/parasitología , Genotipo , Humanos , Ixodes , Maine/epidemiología , Peromyscus/parasitología , Filogenia , Prevalencia , Enfermedades de los Roedores/parasitología , Sciuridae/parasitología , ZoonosisRESUMEN
PURPOSE: To determine the sensibility, the specificity, the positive and negative predictive values of microcalcifications detection by core needle biopsy and intra-operative pathologic examination. MATERIALS AND METHODS: A hundred and one patients (between 1998 and 1999) were investigated in this retrospective study. The initial presentation was breast microcalcifications without palpable tumour. The mean age of patients was 55 (34-79) years. Mammography was performed in 3 standard projections. All suspect microcalcifications were recommended for surgical excision. In the others cases, 5 core biopsies were taken of the lesion. Needle guidance was accomplished by means of either dedicated stereotaxic device or ultrasound equipment. All biopsies were performed with a biopsy device fitted with 14 G needles. The mean follow-up period was 3 years. RESULTS: Clinical or surgical follow-up was available in 101 lesions. Only 4 benign lesions did not have surgery. The 97 remaining were subsequently excised. Pathologic study showed cancer in 38 (39%) lesions, carcinoma in-situ in 14 lesions, and benign disease in 45 lesions. There was 1 false-negative biopsy. The specificity and sensitivity of percutaneous biopsy diagnosis were 73,6 and 93,7% respectively. Intra-operative pathologic diagnoses were concordant in 77% of 30 cases. Discordance occurred in 2 cases of atypical hyperplasia with a single false-negative result for a carcinoma that led to an additional surgical procedure. Positive and negative predictive values of intra-operative pathologic diagnosis were 82 and 100% respectively. CONCLUSION: Needle biopsy findings are accurate and allow definitive therapeutic surgery, including mastectomy.
Asunto(s)
Neoplasias de la Mama/diagnóstico , Calcinosis/diagnóstico , Carcinoma/diagnóstico , Adulto , Anciano , Biopsia con Aguja/métodos , Femenino , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
The authors report a technique of skin resection for mastectomy in order to allow secure, tension free closure using a suture upon the nipple.
Asunto(s)
Antropometría/métodos , Mastectomía/métodos , Cuidados Preoperatorios/métodos , Técnicas de Sutura , Femenino , Humanos , TintaRESUMEN
Cinnamoyl-CoA reductase (CCR; EC 1.2.1.44) catalyses the conversion of cinnamoyl-CoAs into their corresponding cinnamaldehydes, i.e. the first step of the phenylpropanoid pathway specifically dedicated to the monolignol biosynthetic branch. In previous work, we described the isolation and characterisation of the first cDNA encoding CCR in Eucalyptus (Lacombe, E., Hawkins, S., Van Dorsselaere, J., Piquemal, J., Goffner, D., Poeydomenge, O., Boudet, A.M., Grima-Pettenati, J., 1997. Cinnamoyl CoA reductase, the first committed enzyme of the lignin branch biosynthetic pathway: cloning, expression and phylogenetic relationships. Plant Journal 11, 429--441) and shown the role of this enzyme in controlling the carbon flux into lignins (Piquemal, J., Lapierre, C., Myton, K., O'Connell, A., Schuch, W., Grima-Pettenati, J., Boudet, A.M., 1998. Down-regulation of cinnamoyl-CoA reductase induces significant changes of lignin profiles in transgenic tobacco plants. Plant Journal 13, 71--83). Here, we report the characterisation of two functionally and structurally distinct cDNA clones, AtCCR1 and AtCCR2 (81.6% protein sequence identity) in Arabidopsis thaliana. The two recombinant proteins expressed in Escherichia coli are able to use the three cinnamoyl-CoAs tested but with different levels of efficiency. AtCCR1 is five times more efficient with feruloyl-CoA and sinapoyl-CoA than AtCCR2. In addition, the two genes are differentially expressed during development and in response to infection. AtCCR1 is preferentially expressed in tissues undergoing lignification. In contrast, AtCCR2, which is poorly expressed during development, is strongly and transiently induced during the incompatible interaction with Xanthomonas campestris pv. campestris leading to a hypersensitive response. Altogether, these data suggest that AtCCR1 is involved in constitutive lignification whereas AtCCR2 is involved in the biosynthesis of phenolics whose accumulation may lead to resistance.
Asunto(s)
Aldehído Oxidorreductasas/genética , Arabidopsis/genética , Arabidopsis/microbiología , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Xanthomonas campestris/patogenicidad , Aldehído Oxidorreductasas/química , Secuencia de Aminoácidos , Arabidopsis/enzimología , Clonación Molecular , ADN Complementario , Escherichia coli/genética , Datos de Secuencia Molecular , Homología de Secuencia de AminoácidoRESUMEN
Cinnamoyl-CoA reductase (CCR) catalyses the first specific step in the biosynthesis of monolignols, the monomeric units of lignins. We examined the developmental regulation of the Eucalyptus gunnii EgCCR promoter by analysing the expression of EgCCR-GUS fusions in tobacco. EgCCR promoter activity was strongest in lignified organs (stems and roots) consistent with the EgCCR mRNA level in these organs. Histochemical analysis showed expression in vascular tissues (cambium, young differentiating xylem, ray cells, internal and external phloem) of stems and roots in agreement with in situ hybridization data. Promoter deletion analysis and gain-of-function experiments identified the sequences between positions -119 and -77 as necessary and sufficient for expression in vascular tissues of stems. Electrophoretic mobility-shift assays showed that this region is specifically recognized by nuclear proteins present in tobacco stems, giving rise to two retarded complexes, LMC1 and LMC2. Using overlapping EgCCR fragments and mutated oligonucleotides as competitors in gel-shift assays, two DNA-protein interaction sites were mapped. Finally, the role of protein-protein interactions in the formation of the LMC1 and LMC2 complexes was investigated using the detergent sodium deoxycholate, and protein fractionation onto a heparin Sepharose column.
Asunto(s)
Aldehído Oxidorreductasas/genética , ADN de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Aldehído Oxidorreductasas/metabolismo , Secuencia de Bases , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente/genética , Plantas Tóxicas , Regiones Promotoras Genéticas , Nicotiana/genéticaRESUMEN
The vector competence of Ixodes muris (Bishopp & Smith) was determined for Borrelia burgdorferi, the etiologic agent of Lyme disease. Larval I. muris were fed on ICR outbred mice infected with the B-31 laboratory strain of B. burgdorferi. Replete larvae, at 5 d after feeding, were assayed for infection by culture in Barbour-Stoner-Kelly (BSK-H) media. Infection frequency in I. muris replete larvae was 66%. Resultant nymphs were fed on naive ICR outbred mice to determine the ability of I. muris to transmit infection. Infection frequency in fed nymphs declined to 38% and only 1/5 mice was positive for B. burgdorferi on ear biopsy culture. We demonstrated that I. muris is capable of acquiring and transmitting B. burgdorferi but is a relatively poor vector compared with I. scapularis (Say).
Asunto(s)
Vectores Arácnidos/microbiología , Ixodes/microbiología , Enfermedad de Lyme/transmisión , Animales , Femenino , Larva , Ratones , Ninfa/microbiologíaRESUMEN
We report an attempt by an offshore island community to control the vector tick of Lyme disease by providing ivermectin-treated corn to an isolated herd of free-ranging white-tailed deer, Odocoileus virginianus Zimmerman. Medicated corn was supplied in troughs within the island village and from automatic feeders at remote sites during 5 consecutive fall and spring adult tick questing seasons. Acaricide consumption was monitored by assaying its presence in fresh deer pellets and its concentration in deer sera. Its effectiveness was evaluated by recording the number of adult ticks collected from the hides of deer, the number of females becoming sufficiently engorged to oviposit, and the success of subsequent oviposition and eclosion. Entomologic risk was monitored by collecting immature ticks from hosts and adult ticks from vegetation. Estimates based on a subsequent deer reduction program indicated that up to twice as many deer had been present during the project as originally presumed. For this and other reasons related to deer behavior, target levels of serum ivermectin were achieved in a minority of deer. Nevertheless, > 90% control of female tick infestation, subsequent oviposition, and larval eclosion was obtained in those 8 of 16 sampled deer with serum ivermectin levels of > or = 15 ng/ml. In addition, the ratio of females to males, the numbers of females engorging > 10 mg body weight, and the numbers of those eventually hatching, were all significantly less among ticks from island deer in comparison with ticks from untreated deer. No consistent changes in the numbers of ticks found on immature-stage hosts or removed from vegetation were noted within 3 yr of the cessation of treatment.
Asunto(s)
Ciervos/parasitología , Ivermectina/farmacología , Ixodidae , Control de Ácaros y Garrapatas/métodos , Infestaciones por Garrapatas/veterinaria , Zea mays , Alimentación Animal , Animales , Ciervos/fisiología , Maine , Infestaciones por Garrapatas/prevención & controlRESUMEN
Free tick identification has been offered by our laboratory since 1989, during which time > 8,000 specimens have been submitted. We have noted that the bite of 1 of the less frequently identified ticks, Ixodes muris Bishopp & Smith, may be associated with a severe reaction in domestic animals characterized by extreme pain and swelling at the site and, with more complete engorgement, lethargy, anorexia, and high fever. These symptoms may be confused with other serious illness if the tick is not found. This reaction has not been seen following the bite of other species of ixodid ticks in Maine. Here we report 43 such cases, most involving dogs and cats from which ticks were removed by veterinarians and submitted to our laboratory for identification. Although I. muris was initially widespread in the United States and eastern Canada, its current range is unclear. In view of the potential for severe reaction to the bite of I. muris, the current distribution of the tick needs better definition, as does the mechanism of this response in animals that are unnatural hosts.
Asunto(s)
Mordeduras y Picaduras/inmunología , Enfermedades de los Gatos/inmunología , Enfermedades de los Perros/inmunología , Ixodes/inmunología , Infestaciones por Garrapatas/veterinaria , Animales , Enfermedades de los Gatos/parasitología , Gatos , Enfermedades de los Perros/parasitología , Perros , Femenino , Cabras , Infestaciones por Garrapatas/inmunologíaRESUMEN
Ultrasonography and dynamic tomography are used in the study of acute pancreatitis, thus helping to interpret the diverse anatomophysiopathologic variables. We present 41 patients studied by ultrasonography, on admission and twenty-four hours later or more. After seventy-two hours, a dynamic tomography was performed. We did a clinicotomographic correlation assessing necrosis, and multiple Ranson criteria, being complemented with the anatomopathologic study of specimens both in the complications and in the elective biliary surgery. There were three puncture aspirates for bacteriology. Eight (19.5%) patients developed local complications and four (9.75%) presented organ failure. Ultrasonography showed biliopancreatic hypertension in 45% of cases of biliary pancreatitis and was reversible in nature. Dynamic tomography was important in defining morphology and pancreatic necrotic involvement. There were two patients with intrapancreatic necrosis, six with intra and extrapancreatic necrosis and eleven patients who presents a dissemination of the process into the extrapancreatic tissues. The prevalence of glandular necrosis was 24%. Both, ultrasonography and dynamic tomography allowed to the identify a spectrum of lesions representative of cavitated extrapancreatic necrosis and enzymatic pericholecystitis. Likewise, they contributed to define medical treatment as well as indications, opportunities and approaches in the surgical and/or percutaneous treatment of septic complications.
Asunto(s)
Pancreatitis/diagnóstico por imagen , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis/patología , Estudios Prospectivos , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
Ultrasonography and dynamic tomography are used in the study of acute pancreatitis, thus helping to interpret the diverse anatomophysiopathologic variables. We present 41 patients studied by ultrasonography, on admission and twenty-four hours later or more. After seventy-two hours, a dynamic tomography was performed. We did a clinicotomographic correlation assessing necrosis, and multiple Ranson criteria, being complemented with the anatomopathologic study of specimens both in the complications and in the elective biliary surgery. There were three puncture aspirates for bacteriology. Eight (19.5
) patients developed local complications and four (9.75
) presented organ failure. Ultrasonography showed biliopancreatic hypertension in 45
of cases of biliary pancreatitis and was reversible in nature. Dynamic tomography was important in defining morphology and pancreatic necrotic involvement. There were two patients with intrapancreatic necrosis, six with intra and extrapancreatic necrosis and eleven patients who presents a dissemination of the process into the extrapancreatic tissues. The prevalence of glandular necrosis was 24
. Both, ultrasonography and dynamic tomography allowed to the identify a spectrum of lesions representative of cavitated extrapancreatic necrosis and enzymatic pericholecystitis. Likewise, they contributed to define medical treatment as well as indications, opportunities and approaches in the surgical and/or percutaneous treatment of septic complications.
RESUMEN
The effect of a sudden increase in intraocular pressure (IOP) on Eye Bank eyes implanted with a posterior fixation keratoprosthesis PCL5 type (Lacombe) is evaluated. The IOP was artificially increased at a rate close to that observed in direct eye trauma. The critical pressure values causing aqueous humor leak and/or keratoprosthesis extrusion were compared to those found to blow up unoperated eyes. No statistical difference was found between operated and control eyes (6 pairs of eyes). This KPro type showed its efficacy for keratoprosthesis fixation.
Asunto(s)
Humor Acuoso/metabolismo , Trasplante de Córnea , Bancos de Ojos , Presión Intraocular , Tonometría Ocular/efectos adversos , Trasplante de Córnea/efectos adversos , Humanos , Complicaciones Posoperatorias , Tonometría Ocular/instrumentación , Tonometría Ocular/métodosRESUMEN
The first records of 3 ixodid tick species collected in the state of Maine are reported. A total of 23 records of the lone star tick, Amblyomma americanum (L., 1758), in 11 counties from hosts with no history of travel outside the state demonstrates that this tick is now a resident of Maine. Ixodes dentatus Marx, 1899 is recorded from Waldo and Lincoln counties, and Ixodes uriae White, 1852 is recorded from Matinicus Rock in Knox County. This is the first report of I. uriae from the eastern United States. Disease agents such as those causing human monocytic ehrlichiosis, Lyme disease, Rocky Mountain spotted fever, and several arboviruses have been recorded from 1 or more of these tick species.
Asunto(s)
Ixodes/crecimiento & desarrollo , Infestaciones por Garrapatas/parasitología , Garrapatas/crecimiento & desarrollo , Animales , Femenino , Humanos , Maine/epidemiología , Masculino , Infestaciones por Garrapatas/epidemiologíaRESUMEN
The contribution of migratory and resident birds to the introduction of Lyme disease will vary with the degree to which various species expose themselves to, and are infested by, juvenile vector ticks, and their ability to support and transmit the infectious agent. To examine the relative contribution of various passerine species during the emergence of this disease, we compared the abundance and infection rates of the blacklegged tick, Ixodes scapularis Say, removed from mist-netted birds with those from live-trapped mice at a coastal study site in southern Maine, collected during an 8-yr period in which the range of this tick and the incidence of Lyme disease increased in the state. Weekly bird-banding sessions using six 12-m Japanese mist nets were carried out from May through August 1989-1996. In 1989, 1991 and 1993, mice were live-trapped in a Sherman trap grid (7 by 7 m) during five 3-night sessions, June through August; in 1994-1996, 2 such grids were similarly trapped. Annual adult tick abundance was estimated by flagging vegetation. We removed 2,633 juvenile deer ticks from 1,713 of 1,972 birds examined. Twenty-five of 64 bird species were infested. The percentages of birds infested and the rate of infection among removed larvae and nymphs increased over the years, but species varied markedly in their ability to infect ticks. No infected larvae were removed from catbirds or towhees. The larval to nymphal ratio was higher in mice than in birds. Infection rates among bird-derived larvae were less than among mice-derived larvae, but increased with time. Because of the different ways in which individual species of passerine birds contribute to the availability of vector ticks and respond to the agent of Lyme disease in emerging areas, further research into host competency and borreliacidal mechanisms is needed.
Asunto(s)
Vectores Artrópodos/microbiología , Enfermedades de las Aves/parasitología , Aves/parasitología , Ixodes/microbiología , Enfermedad de Lyme/epidemiología , Infestaciones por Garrapatas/veterinaria , Animales , Larva/microbiología , Maine/epidemiología , Ratones/parasitología , Ninfa/microbiología , Dinámica Poblacional , Prevalencia , Sciuridae/parasitología , Estaciones del Año , Especificidad de la EspecieRESUMEN
Cinnamoyl CoA:NADP oxidoreductase (CCR, EC 1.2.1.44) catalyzes the conversion of cinnamoyl CoA esters to their corresponding cinnamaldehydes, i.e. the first specific step in the synthesis of the lignin monomers. The cloning of a cDNA encoding CCR in Eucalyptus gunnii (EUCCR) is reported here. The identity of the EUCCR cDNA was demonstrated by comparison with peptide sequence data from purified CCR and functional expression of the recombinant enzyme in Escherichia coli. Sequence analysis revealed remarkable homologies with dihydroflavonol-4-reductase (DFR), the first enzyme of the anthocyanin biosynthetic pathway. Moreover, significant similarities were found with mammalian 3 beta-hydroxysteroid dehydrogenase and bacterial UDP-galactose-4-epimerase, suggesting that CCR shared a common ancestor with these enzymes and can therefore be considered as a new member of the mammalian 3 beta-hydroxysteroid dehydrogenase/ plant dihydroflavonol reductase superfamily. In Eucalyptus gunnii, CCR is encoded by one gene containing four introns whose positions are similar to those of introns I, II, III and V in DFR genes from dicots. In agreement with the involvement of CCR in lignification, the CCR transcript was shown to be expressed in lignified organs, i.e. root and stem tissues, and was localized mainly in young differentiating xylem. On the other hand, its abundance in Eucalyptus leaves suggests that monolignols may be precursors of end products other than lignins. This first characterization of a gene corresponding to CCR opens new possibilities to genetically engineer plants with lower lignin content. This is particularly important for woody plants such as Eucalyptus which are used for pulp making.
Asunto(s)
Aldehído Oxidorreductasas/biosíntesis , Aldehído Oxidorreductasas/genética , Eucalyptus/enzimología , Lignina/biosíntesis , Filogenia , Plantas Medicinales , Aldehído Oxidorreductasas/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario , Escherichia coli , Eucalyptus/genética , Humanos , Hibridación in Situ , Mamíferos , Datos de Secuencia Molecular , Familia de Multigenes , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Homología de Secuencia de AminoácidoRESUMEN
To investigate a low rate of reported human Lyme disease adjacent to an area where the vector tick had become well established, we performed human and canine serosurveys and gathered data on environmental factors related to the risk of transmission. In March 1993, we obtained serum samples and conducted questionnaires that included information on outdoor activities, lot size, and frequency of deer sightings from 272 individuals living within a 5-km strip extending 12 km inland from a study site in south coastal Maine where collections revealed an abundant population of deer ticks. Serologic analysis was done using a flagellin-based enzyme-linked immunosorbent assay (ELISA) followed by Western immunoblot of positive and equivocal samples. Sera from 71 unvaccinated dogs within the study area were also analyzed for anti-Borrelia antibodies by ELISA. Human seropositivity was limited to two individuals living within 1.2 km of the coast. The frequency of daily deer sightings decreased sharply outside this area. Canine seropositivity, 100% within the first 0.8 km, decreased to 2% beyond 1.5 km. Canine serology appears to correlate with the entomologic indicators of the risk of Lyme disease transmission. Possible explanations for the low human seroprevalence are offered.