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OBJECTIVE: Adolescent diet, physical activity and nutritional status are generally known to be sub-optimal. This is an introduction to a special issue of papers devoted to exploring factors affecting diet and physical activity in adolescents, including food insecure and vulnerable groups. SETTING: Eight settings including urban, peri-urban and rural across sites from five different low- and middle-income countries. DESIGN: Focus groups with adolescents and caregivers carried out by trained researchers. RESULTS: Our results show that adolescents, even in poor settings, know about healthy diet and lifestyles. They want to have energy, feel happy, look good and live longer, but their desire for autonomy, a need to 'belong' in their peer group, plus vulnerability to marketing exploiting their aspirations, leads them to make unhealthy choices. They describe significant gender, culture and context-specific barriers. For example, urban adolescents had easy access to energy dense, unhealthy foods bought outside the home, whereas junk foods were only beginning to permeate rural sites. Among adolescents in Indian sites, pressure to excel in exams meant that academic studies were squeezing out physical activity time. CONCLUSIONS: Interventions to improve adolescents' diets and physical activity levels must therefore address structural and environmental issues and influences in their homes and schools, since it is clear that their food and activity choices are the product of an interacting complex of factors. In the next phase of work, the Transforming Adolescent Lives through Nutrition consortium will employ groups of adolescents, caregivers and local stakeholders in each site to develop interventions to improve adolescent nutritional status.
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Comportamento Alimentar , Estado Nutricional , Adolescente , África Subsaariana , Dieta , Exercício Físico , HumanosRESUMO
Since 2018, following a revision of the German Social Code Book V (SGB V), it has been possible for psychiatric hospitals to provide inpatient outreach treatment in the domestic environment of psychiatric patients. Special structural features and documentation requirements must be observed. In addition to a member of the medical and nursing professions, the treatment team must include at least one member of a third professional group (e.g. occupational therapy, social work, physiotherapy). The reimbursement of services is negotiated between the respective medical institution and the health insurance companies and includes regionally divergent billing on the basis of lump sums, per minute worked or mixed models. From a psychiatric psychotherapeutic point of view the treatment of gerontopsychiatric patients in their living environment and thus in their social context offers many advantages. A prerequisite for the success of this approach is a multiprofessional treatment team that is also experienced in somatic illnesses and logistically highly flexible. Under the conditions of the corona pandemic special challenges arise from the prohibition of visiting nursing homes and the risk of infection for patients and members of the treatment team associated with outreach work.
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Atenção à Saúde/métodos , Hospitalização , Hospitais Psiquiátricos , Pacientes Internados , Geriatria/métodos , Humanos , Psiquiatria/métodosRESUMO
Studies of caterpillar defense strategy evolution typically focus on aposematic coloration, gregarious behavior, and/or chemical defense. In the slug moth family Limacodidae, the evolution of chemical defense is coupled to the life history trait of first instar feeding behaviors. In nettle caterpillars, the first instars fast and molt into a second instar that feeds. In contrast, gelatines and monkey slug larval forms feed in the first instar. This study focused on whether the evolution of fasting associated with the nettle morphology was a derived trait of single or multiple origins. Twenty-nine species of Limacodidae (including one Chrysopolominae) representing 27 genera and four outgroup species with known first and final instar morphologies and behaviors were included. Four out-group species representing Megalopygidae (1 sp), Dalceridae (1 sp) and Aididae (2 sp) were included. These were sequenced for three molecular markers for a total of 4073 bp, mitochondrial COI (â¼1500 bp), 18S (â¼1900 bp) and the D2 region of 28S (approximately 670 bp). Maximum likelihood and Bayesian analyses were conducted. The resulting phylogeny and comparative analysis of feeding strategy revealed that the nettle caterpillar morphology and behavior of larval fasting may have a single origin.
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Jejum , Mariposas/fisiologia , Animais , Evolução Biológica , Feminino , Larva/genética , Mariposas/genética , Fenótipo , FilogeniaRESUMO
BACKGROUND: Rigorously applied exercise interventions undertaken in a research setting result in improved health-related quality of life (hrqol) in cancer survivors, but research to demonstrate effective translation of that research to practice is needed. The objective of the present study was to determine the effect of fee-for-service cancer rehabilitation programs in the community on hrqol and on self-reported physical activity and its correlates. METHODS: After enrolment and 17 ± 4 weeks later, new clients (n = 48) to two fee-for-service cancer rehabilitation programs completed the 36-Item Short Form Health Survey (rand-36: rand Corporation, Santa Monica, CA, U.S.A.), the Godin Leisure-Time Exercise Questionnaire, and questions about physical activity correlates. Normal fee-for-service operations were maintained, including a fitness assessment and individualized exercise programs supervised in a group or one-on-one setting, with no minimum attendance required. Fees were associated with the assessment and with each exercise session. RESULTS: Of the 48 participants, 36 (75%) completed both questionnaires. Improvements in the physical functioning, role physical, pain, and energy/fatigue scales on the rand-36 exceeded minimally important differences and were of a magnitude similar to improvements reported in structured, rigorously applied, and free research interventions. Self-reported levels of vigorous-intensity (p = 0.021), but not moderate-intensity (p = 0.831) physical activity increased. The number of perceived barriers to exercise (p = 0.035) and the prevalence of fatigue as a barrier (p = 0.003) decreased. Exercise self-efficacy improved only in participants who attended 11 or more sessions (p = 0.002). Exercise enjoyment did not change (p = 0.629). CONCLUSIONS: Enrolment in fee-for-service cancer rehabilitation programs results in meaningful improvements in hrqol comparable to those reported by research interventions, among other benefits. The fee-for-service model could be an effective model for delivery of exercise to more cancer survivors.
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Hybrid zones may serve as bridges permitting gene flow between species, including alleles influencing the evolution of breeding systems. Using greenhouse crosses, we assessed the likelihood that a hybrid zone could serve as a conduit for transfer of nuclear male-sterility alleles between a gynodioecious species and a hermaphroditic species with very rare females in some populations. Segregation patterns in progeny of crosses between rare females of hermaphroditic Schiedea menziesii and hermaphroditic plants of gynodioecious Schiedea salicaria heterozygous at the male-sterility locus, and between female S. salicaria and hermaphroditic plants from the hybrid zone, were used to determine whether male-sterility was controlled at the same locus in the parental species and the hybrid zone. Segregations of females and hermaphrodites in approximately equal ratios from many of the crosses indicate that the same nuclear male-sterility allele occurs in the parent species and the hybrid zone. These rare male-sterility alleles in S. menziesii may result from gene flow from S. salicaria through the hybrid zone, presumably facilitated by wind pollination in S. salicaria. Alternatively, rare male-sterility alleles might result from a reversal from gynodioecy to hermaphroditism in S. menziesii, or possibly de novo evolution of male sterility. Phylogenetic analysis indicates that some species of Schiedea have probably evolved separate sexes independently, but not in the lineage containing S. salicaria and S. menziesii. High levels of selfing and expression of strong inbreeding depression in S. menziesii, which together should favour females in populations, argue against a reversal from gynodioecy to hermaphroditism in S. menziesii.
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Caryophyllaceae/fisiologia , Polinização , Alelos , Fluxo Gênico , Hibridização Genética , Filogenia , ReproduçãoRESUMO
Triple negative breast cancer (TNBC) is known for its heterogeneous nature and aggressive onset, limited unresponsiveness to hormone therapies and immunotherapy as well as high likelihood of metastasis and recurrence. Since no targeted standard treatment options are available for TNBC, novel and effective therapeutic targets are urgently needed. Ion channels have emerged as possible novel therapeutic candidates for cancer therapy. We previously showed that GABAA ß3 subunit are expressed at higher levels in TNBC cell lines than non-tumorigenic MCF10A cells. GABAA ß3 subunit knockdown causes cell cycle arrest in TNBC cell lines via decreased cyclin D1 and increased p21 expression. However, it is not known if the upregulated GABAAR express at the cell-surface in TNBC and mediate Cl- flux. Cl- ions are known to play a role in cell-cycle progression in other cancers such as gastric cancer. Here, using surface biotinylation and (N-(Ethoxycarbonylmethyl)-6-Methoxyquinolinium Bromide) MQAE-dye based fluorescence quenching, we show that upregulated GABAAR are on the cell-surface in TNBC cell lines and mediate significantly higher chloride (Cl-) flux as compared to non-tumorigenic MCF10A cells. Moreover, this GABAAR mediated Cl- flux can be modulated by pharmacological agents and is decreased in TNBC cells with GABAA ß3 subunit knockdown. Further, treatment of TNBC cells with bicuculline, a GABAAR antagonist reduced cell viability in TNBC cells Overall, these results point to an unexplored role of GABAAR mediated Cl- flux in TNBC.
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Within butterflies and moths, adult hematophagy is limited to species within the vampire moth genus Calyptra. These moths are placed within the subfamily Calpinae, whose other members are known to exhibit a broad range of feeding behaviors including those that can be considered 'piercers' of fruits or other hosts and 'tear feeders'. Here, we reconstruct a phylogenetic hypothesis of Calpinae using molecular data to test whether hematophagy in Calyptra arose from plant or animal-related behaviors. We use a Bayesian method of ancestral state reconstruction to determine the most likely feeding behaviors for the subtribes and genera within this lineage.
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Comportamento Alimentar , Mariposas/classificação , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Frutas , Genes de Insetos , Funções Verossimilhança , Modelos Genéticos , Mariposas/genéticaRESUMO
Although the spatial separation of sexual organs within a flower (herkogamy) has been interpreted as a mechanism that promotes efficient pollen transfer, there have been few attempts to relate variation in herkogamy to probabilities of pollen flow. Here, we used a heterostylous species with variation in reciprocal herkogamy to test this hypothesis. We measured legitimate and illegitimate pollen flow with fluorescent dyes in four selected populations of Oxalis alpina corresponding to the extremes of a previously reported evolutionary gradient from tristyly to distyly. After the breakdown of tristyly, the observed increment in reciprocal herkogamy between the long and short morphs was associated with a 30% increase in the proportion of dye received from compatible illegitimate pollinations. In all populations, the most likely effective pollen vectors were two Heterosarus bee species. Our results support the adaptive value of reciprocal herkogamy in promoting efficient pollen transfer in heterostylous species.
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Adaptação Biológica/fisiologia , Abelhas/fisiologia , Flores/fisiologia , Magnoliopsida/fisiologia , Polinização/fisiologia , Animais , Flores/anatomia & histologia , Corantes Fluorescentes , Magnoliopsida/anatomia & histologia , MéxicoRESUMO
UNLABELLED: INTRODUCTION. Botulinum toxin A (BoNTA) is an alternative in children with neurogenic bladder refractory to anticholinergics. OBJECTIVE. To evaluate the initial effects of BoNTA in neurogenic bladders. PATIENTS AND METHODS 12 patients (9 myelomeningoceles, 1 tethered cord, 1 medullary astrocytoma, 1 Ewing's sarcoma) were studied. The pretreatment evaluation included: voiding diary, incontinence score, renovesical ultrasound, cystourethrography and urodynamic parameters. Patients received 300 UI of BoNTA via detrusor injections. They were re-evaluated at months 1, 3 and 6. After the third control, if improvement was confirmed, patients were injected again. Otherwise, surgery was indicated. RESULTS: After the initial injection, 50% of patients achieved complete continence and 20% remained with minimal leaks. The mean maximum bladder capacity increased from 264 +/- 117 ml to 324 +/- 170 ml (P = 0.322). The mean detrusor pressure decreased from 46 +/- 17 cm H2O to 42 +/- 14 cm H2O (P=0.596). The mean bladder compliance increased from 7.6 +/- 5.9 ml/cm H2O to 10.4 +/- 6.4 ml/cm H2O (P = 0.290). The reflex voiding contractions disappeared in 2 patients; 8 presented trabeculae. Ten patients were reinjected and two underwent surgery. CONCLUSION: 70% urinary continence was achieved after the initial injection. No significant urodynamic changes were observed. A longer follow-up with subsequent injections is needed.
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Toxinas Botulínicas Tipo A/uso terapêutico , Fármacos Neuromusculares/uso terapêutico , Bexiga Urinaria Neurogênica/tratamento farmacológico , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos ProspectivosRESUMO
PURPOSE: The potential of physical activity to improve function and quality of life of an individual with advanced cancer is now established. The purpose of this survey of oncologic healthcare providers (OHPs) is to understand their attitude towards physical activity for individuals living with bony metastases and to assess requirements to confidently provide physical activity recommendations. METHODS: A web-based survey administered through Qualtrics™ included questions on participant demographics and attitude questions ranked on a Likert scale. Eligibility was a physician or nurse practitioner currently providing care in the cancer care system of a public healthcare system in Canada. 338 participants were identified and invited to participate in this survey. RESULTS: The response rate was 34.6%. The majority of OHPs believed physical activity is important (89%) and safe (82%) in individuals living with bony metastases. OHPs agreed that these individuals looked to them for physical activity recommendations (74%) and that these recommendations would be followed (58%). Yet, 86% of OHPs felt they required more information before they could recommend physical activity to individuals living with bony metastases, and less than half (43%) of OHPs felt confident enough to prescribe physical activity. CONCLUSIONS: OHPs agree that physical activity for individuals living with bony metastatic cancer is beneficial and safe. However, OHPs are not confident in their ability to recommend physical activity to this population. IMPLICATIONS FOR CANCER SURVIVORS: There is a need to create physical activity guidelines for individuals living with bony metastases and improve access to rehabilitation services.
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Sobreviventes de Câncer , Neoplasias , Exercício Físico , Pessoal de Saúde , Humanos , Oncologia , Qualidade de VidaRESUMO
Pleistocene climatic oscillations are known to influence the patterns of genetic diversity and the distribution of traits that are the target of selection. Here, we combine phylogeographical and ecological niche modelling (ENM) approaches to explore the influence of historical factors (Pleistocene climatic shifts) and natural selection on the evolution of distyly (two floral morphs) from tristyly (three floral morphs) of Oxalis alpina in the Sky Islands of the Sonoran Desert. Molecular data and ENM indicate that historical factors have had a strong influence on the genetic structure and the geographical distribution of reproductive systems of O. alpina. Moreover, genetic results suggest the possibility that distylous populations do not represent a monophyletic group. We propose that the combined effects of natural selection and genetic drift have influenced the tristyly-distyly transition.
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Evolução Biológica , Flores/fisiologia , Magnoliopsida/genética , Modelos Genéticos , Seleção Genética , Arizona , Clima Desértico , Ecossistema , Deriva Genética , Variação Genética , Haplótipos , México , New Mexico , FilogeografiaRESUMO
Herbicide resistance has been observed in Chloris truncata, an Australian native C4 grass and a summer-fallow weed, which is common in no-till agriculture situations where herbicides are involved in crop management. To investigate the role of drought and increased atmospheric carbon dioxide (CO2) in determining weed growth, three trials were conducted using a 'glyphosate-resistant' and a 'glyphosate-susceptible' biotype. The first two trials tested the effect of herbicide (glyphosate) application on plant survival and growth under moisture stress and elevated CO2 respectively. A third trial investigated the effect on plant growth and reproduction under conditions of moisture stress and elevated CO2 in the absence of herbicide. In the first trial, water was withheld from half of the plants prior to application of glyphosate to all plants, and in the second trial plants were grown in either ambient (450 ppm) or elevated CO2 levels (750 ppm) prior to, and following, herbicide application. In both biotypes, herbicide effectiveness was reduced when plants were subjected to moisture stress or if grown in elevated CO2. Plant productivity, as measured by dry biomass per plant, was reduced with moisture stress, but increased with elevated CO2. In the third trial, growth rate, biomass and seed production were higher in the susceptible biotype compared to the resistant biotype. This suggests that a superior ability to resist herbicides may come at a cost to overall plant fitness. The results indicate that control of this weed may become difficult in the future as climatic conditions change.
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Murine antisera with neutralising activity for the coronavirus causative of Middle East respiratory syndrome (MERS) were induced by immunisation of Balb/c mice with the receptor binding domain (RBD) of the viral Spike protein. The murine antisera induced were fully-neutralising in vitro for two separate clinical strains of the MERS coronavirus (MERS-CoV). To test the neutralising capacity of these antisera in vivo, susceptibility to MERS-CoV was induced in naive recipient Balb/c mice by the administration of an adenovirus vector expressing the human DPP4 receptor (Ad5-hDPP4) for MERS-CoV, prior to the passive transfer of the RBD-specific murine antisera to the transduced mice. Subsequent challenge of the recipient transduced mice by the intra-nasal route with a clinical isolate of the MERS-CoV resulted in a significantly reduced viral load in their lungs, compared with transduced mice receiving a negative control antibody. The murine antisera used were derived from mice which had been primed sub-cutaneously with a recombinant fusion of RBD with a human IgG Fc tag (RBD-Fc), adsorbed to calcium phosphate microcrystals and then boosted by the oral route with the same fusion protein in reverse micelles. The data gained indicate that this dual-route vaccination with novel formulations of the RBD-Fc, induced systemic and mucosal anti-viral immunity with demonstrated in vitro and in vivo neutralisation capacity for clinical strains of MERS-CoV.
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Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Animais , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Modelos Animais de Doenças , Feminino , Imunidade nas Mucosas/fisiologia , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos , Carga ViralRESUMO
Sex allocation theory addresses how separate sexes can evolve from hermaphroditism but little is known about the genetic potential for shifts in sex allocation in flowering plants. We tested assumptions of this theory using the common currency of biomass and measurements of narrow-sense heritabilities and genetic correlations in Schiedea salicaria, a gynodioecious species under selection for greater differentiation of the sexes. Female (carpel) biomass showed heritable variation in both sexes. Male (stamen) biomass in hermaphrodites also had significant heritability, suggesting the potential for further evolution of dioecy. Significant positive genetic correlations between females and hermaphrodites in carpel mass may slow differentiation between the sexes. Within hermaphrodites, there were no negative genetic correlations between male and female biomass as assumed by models for the evolution of dioecy, suggesting that S. salicaria is capable of further changes in biomass allocation to male and female functions and evolution toward dioecy.
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Evolução Biológica , Caryophyllaceae/fisiologia , Flores/fisiologia , Caryophyllaceae/genética , Reprodução/genética , Reprodução/fisiologia , Caracteres SexuaisRESUMO
Patients with defects in the biogenesis of peroxisomes include those with Zellweger syndrome spectrum (ZSS), a developmental and progressive metabolic disease with a distinct dysmorphic phenotype and varying severity. The diagnosis of ZSS relies on the clinical presentation and the biochemical evaluation of peroxisomal metabolites. Mutation detection in one out of twelve genes coding for proteins involved in the biogenesis of peroxisomes confirms the diagnosis. In the absence of pronounced clinical features of ZSS, neuroradiological findings may lead the way to the diagnosis. Cerebral magnetic resonance imaging (cMRI) pathology in ZSS consists of abnormal gyration pattern including polymicrogyria and pachygyria, leukencephalopathy, germinolytic cysts and heterotopias as reported by previous systematic studies including cMRI of a total of 34 ZSS patients, only five of whom had a severe phenotype. The present study evaluated the cMRI results of additional 18 patients, 6 with a severe and 12 with a milder ZSS phenotype. It confirms and extends knowledge of the characteristic cMRI pattern in ZSS patients. Besides an abnormal gyration pattern and delayed myelination or leukencephalopathy, brain atrophy was a common finding. Polymicrogyria and pachygyria were more common in patients with severe ZSS, while leukencephalopathy increases with age in patients with longer survival. Nevertheless, an abnormal gyration pattern might be more frequent in patients with a mild ZSS than deduced from previous studies. In addition, we discuss the differential diagnosis of the ZSS cMRI pattern and review investigations on the pathogenesis of the ZSS cerebral phenotype in mouse models of the disease.
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Encéfalo/patologia , Imageamento por Ressonância Magnética , Síndrome de Zellweger/diagnóstico , Animais , Encéfalo/metabolismo , Pré-Escolar , Análise Mutacional de DNA , Diagnóstico Diferencial , Modelos Animais de Doenças , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Camundongos , Mutação , Fenótipo , Valor Preditivo dos Testes , Prognóstico , Índice de Gravidade de Doença , Síndrome de Zellweger/genética , Síndrome de Zellweger/metabolismo , Síndrome de Zellweger/mortalidade , Síndrome de Zellweger/patologiaRESUMO
OBJECTIVE: Appendicovesicostomy (APV) and Monti ileovesicostomy (Monti) are durable catheterizable channels. While subfascial revision rates vary by channel type, a channel implanted in the anterior (vs posterior) aspect of the bladder may have a lower subfascial revision risk, due to decreased channel mobility and better fascial fixation. The present study aimed to compare long-term durability of anteriorly compared to posteriorly implanted APV and Monti channels in a large international cohort. MATERIALS AND METHODS: A retrospective cohort study was conducted on patients aged ≤21 years and who underwent APV or Monti surgery with an open technique at three high-volume centers (1990-2015). The following were noted: patient demographics, stomal and subfascial revisions, stomal location, channel placement (anterior/posterior), and channel type - APV, spiral Monti to umbilicus (SMU), other Monti channels. Survival analysis and Cox proportional hazards regression were used to separately examine the three channel groups. RESULTS: Of the 675 patients who met inclusion criteria, 387 had an APV (71.3% anterior), 53 had an SMU (13.2% anterior) and 235 had other Monti channels (42.1% anterior). Median age at surgery was 8.8 years for APV (median follow-up: 5.5 years), 9.2 years for other Monti (follow-up: 6.6 years) and 7.9 years for SMU (follow-up: 9.0 years). Patients originated from the USA (67.9%), Argentina (26.4%) and Chile (5.8%). Overall, 76 stomal and 77 subfascial revisions occurred. Risk of stomal revision was 9.3-12.0% at 5 years of follow-up, and was similar between channel types or location (P = 0.57). Risk of subfascial revision at 5 years was 7.4% for APV, 12.7% for all other Monti channels and 25.9% for SMU (P = 0.001). On survival analysis, stomal and subfascial revision rates were similar between anterior and posterior channels for APV (P ≥ 0.16), other Monti channels (P ≥ 0.62) and SMU (P ≥ 0.43) (Summary Fig.). On multivariate regression, channel configuration was not associated with stomal or subfascial revision for APV (P ≥ 0.18) or other Monti channels (P ≥ 0.64). Sex, age, diagnosis, country and stomal location were not associated with revision risk (P ≥ 0.06). DISCUSSION: Contrary to the hypothesis, subfascial revision rates were no different between anterior and posterior channels. Given that many reported outcomes related to genitourinary reconstruction occur rarely and require prolonged follow-up, collaborative research in this area should be encouraged. CONCLUSIONS: The study demonstrated durable long-term results with the APV and Monti techniques in an international cohort. Risks of stomal and subfascial complications were not significantly different between anteriorly and posteriorly implanted channels. As previously reported, Monti channels, particularly SMU, were more prone to undergoing subfascial revisions.
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Cistostomia/métodos , Cateterismo Urinário/métodos , Derivação Urinária/métodos , Coletores de Urina , Procedimentos Cirúrgicos Urológicos/métodos , Adolescente , Fatores Etários , Argentina , Criança , Pré-Escolar , Chile , Estudos de Coortes , Cistostomia/efeitos adversos , Seguimentos , Humanos , Internacionalidade , Masculino , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Modelos de Riscos Proporcionais , Reoperação/métodos , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos , Procedimentos Cirúrgicos Urológicos/efeitos adversos , Adulto JovemRESUMO
The herpes simplex virus type 1 genome (160 kilobases) contains three origins of DNA synthesis: two copies of oriS located within the repeated sequences flanking the short unique arm (US), and one copy of oriL located within the long unique arm (UL). Precise localization and characterization of oriL have been severely hampered by the inability to clone sequences which contain it (coordinates 0.398 to 0.413) in an undeleted form in bacteria. We report herein the successful cloning of sequences between 0.398 to 0.413 in an undeleted form, using a yeast cloning vector. Sequence analysis of a 425-base pair fragment spanning the deletion-prone region has revealed a perfect 144-base pair palindrome with striking homology to oriS. In a functional assay, the undeleted clone was amplified when functions from herpes simplex virus type 1 were supplied in trans, whereas clones with deletions of 55 base pairs or more were not amplified.
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Replicação do DNA , DNA Viral/biossíntese , Genes Virais , Simplexvirus/genética , Replicação Viral , Sequência de Bases , Deleção Cromossômica , Mapeamento Cromossômico , Clonagem Molecular , DNA Viral/genética , Amplificação de Genes , Vetores Genéticos , Conformação de Ácido NucleicoRESUMO
Real-time (TaqMan) PCR assays were developed to detect the strawberry angular leaf spot pathogen Xanthomonas fragariae (Xf) and the strawberry bacterial blight pathogen Xanthomonas arboricola pv. fragariae (Xaf). The Xf PCR (Xf gyrB) was designed within regions of the gyraseB gene, unique to Xf, after generating gyraseB DNA sequence data from Xf and other closely related strains. The Xaf PCR (Xaf pep) was designed within regions of the pep prolyl endopeptidase gene that were unique to Xaf, after generating pep DNA sequence data from Xf and Xaf strains. The Xf gyrB PCR detected only Xf strains amongst a panel of 20 Xanthomonas-related spp. and pathovars. The Xaf pep PCR assay detected all Xaf strains tested plus two other (of three tested) X. arboricola pathovars. An existing genomic DNA extraction protocol was modified to facilitate detection of both pathogens to 10(3) cells per strawberry leaf disc.
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Fragaria/microbiologia , Folhas de Planta/microbiologia , Reação em Cadeia da Polimerase/métodos , Xanthomonas/isolamento & purificação , DNA Girase/genética , Primers do DNA/genética , Prolil Oligopeptidases , Sensibilidade e Especificidade , Serina Endopeptidases/genética , Xanthomonas/genéticaRESUMO
Pollen and stigma size have the potential to influence male fitness of hermaphroditic plants, particularly in species presenting floral polymorphisms characterised by marked differences in these traits among floral morphs. In this study, we take advantage of the evolutionary transition from tristyly to distyly experienced by Oxalis alpina (Oxalidaceae), and examined whether modifications in the ancillary traits (pollen and stigma size) respond to allometric changes in other floral traits. Also, we tested whether these modifications are in accordance with what would be expected under the hypothesis that novel competitive scenarios (as in distylous-derived reproductive system) exert morph- and whorl-specific selective pressures to match the available stigmas. We measure pollen and stigma size in five populations of O. alpina representing the tristyly-distyly transition. A general reduction in pollen and stigma size occurred along the tristyly-distyly transition, and pollen size from the two anther levels within each morph converged to a similar size that was characterised by whorl-specific changes (increases or decreases) in pollen size of different anthers in each floral type. Overall, results from this study show that the evolution of distyly in this species is characterised not only by changes in sexual organ position and flower size, but also by morph-specific changes in pollen and stigma size. This evidence supports the importance of selection on pollen and stigma size, which increase fitness of remaining morphs following the evolution of distyly, and raises questions to explore on the functional value of pollen size in heterostylous systems under pollen competition.
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Flores/fisiologia , Oxalidaceae/fisiologia , Pólen/fisiologia , Evolução Biológica , Flores/anatomia & histologia , Oxalidaceae/anatomia & histologia , Pólen/anatomia & histologia , Reprodução/fisiologiaRESUMO
Helicases play essential roles in many important biological processes such as DNA replication, repair, recombination, transcription, splicing, and translation. Many bacteriophages and plant and animal viruses encode one or more helicases, and these enzymes have been shown to play many roles in their respective viral life cycles. In this review we concentrate primarily on the roles of helicases in DNA replication and recombination with special emphasis on the bacteriophages T4, T7, and A as model systems. We explore comparisons between these model systems and the herpesviruses--primarily herpes simplex virus. Bacteriophage utilize various pathways of recombination-dependent DNA replication during the replication of their genomes. In fact the study of recombination in the phage systems has greatly enhanced our understanding of the importance of recombination in the replication strategies of bacteria, yeast, and higher eukaryotes. The ability to "restart" the replication process after a replication fork has stalled or has become disrupted for other reasons is a critical feature in the replication of all organisms studied. Phage helicases and other recombination proteins play critical roles in the "restart" process. Parallels between DNA replication and recombination in phage and in the herpesviruses is explored. We and others have proposed that recombination plays an important role in the life cycle of the herpesviruses, and in this review, we discuss models for herpes simplex virus type 1 (HSV-1) DNA replication. HSV-1 encodes two helicases. UL9 binds specifically to the origins of replication and is believed to initiate HSV DNA replication by unwinding at the origin; the heterotrimeric helicase-primase complex, encoded by UL5, UL8, and UL52 genes, is believed to unwind duplex viral DNA at replication forks. Structure-function analyses of UL9 and the helicase-primase are discussed with attention to the roles these proteins might play during HSV replication.