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1.
Model Earth Syst Environ ; 8(4): 5493-5520, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814616

RESUMO

A new mathematical model incorporating epidemiological features of the co-dynamics of tuberculosis (TB) and SARS-CoV-2 is analyzed. Local asymptotic stability of the disease-free and endemic equilibria are shown for the sub-models when the respective reproduction numbers are below unity. Bifurcation analysis is carried out for the TB only sub-model, where it was shown that the sub-model undergoes forward bifurcation. The model is fitted to the cumulative confirmed daily SARS-CoV-2 cases for Indonesia from February 11, 2021 to August 26, 2021. The fitting was carried out using the fmincon optimization toolbox in MATLAB. Relevant parameters in the model are estimated from the fitting. The necessary conditions for the existence of optimal control and the optimality system for the co-infection model is established through the application of Pontryagin's Principle. Different control strategies: face-mask usage and SARS-CoV-2 vaccination, TB prevention as well as treatment controls for both diseases are considered. Simulations results show that: (1) the strategy against incident SARS-CoV-2 infection averts about 27,878,840 new TB cases; (2) also, TB prevention and treatment controls could avert 5,397,795 new SARS-CoV-2 cases. (3) In addition, either SARS-CoV-2 or TB only control strategy greatly mitigates a significant number of new co-infection cases.

2.
Plant Biol (Stuttg) ; 17(2): 551-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25115902

RESUMO

Pollination syndromes are defined as suites of floral traits evolved in response to selection imposed by a particular group of pollinators (e.g., butterflies, hummingbirds, bats). Although numerous studies demonstrated their occurrence in plants pollinated by radically different pollinators, it is less known whether it is possible to identify them within species pollinated by one functional pollinator group. In such a framework, we expect floral traits to evolve also in response to pollinator subgroups (e.g., species, genera) within that unique functional group. On this, specialised pollination systems represent appropriate case studies to test such expectations. Calceolaria is a highly diversified plant genus pollinated by oil-collecting bees in genera Centris and Chalepogenus. Variation in floral traits in Calceolaria has recently been suggested to reflect adaptations to pollinator types. However, to date no study has explicitly tested that observation. In this paper, we quantitatively test that hypothesis by evaluating the presence of pollination syndromes within the specialised pollination system formed by several Calceolaria and their insect pollinators. To do so, we use multivariate approaches and explore the structural matching between the morphology of 10 Calceolaria taxa and that of their principal pollinators. Our results identify morphological matching between floral traits related to access to the reward and insect traits involved in oil collection, confirming the presence of pollinator syndromes in Calceolaria. From a general perspective, our findings indicate that the pollination syndrome concept can be also extended to the intra-pollinator group level.


Assuntos
Calceolariaceae/fisiologia , Flores/fisiologia , Polinização , Animais , Abelhas , Calceolariaceae/anatomia & histologia , Chile , Flores/anatomia & histologia , Insetos , Herança Multifatorial , Análise Multivariada , Análise de Componente Principal
3.
Plant Dis ; 98(9): 1205-1212, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30699612

RESUMO

Phymatotrichopsis omnivora, the causal pathogen of cotton root rot, is a devastating ascomycete that affects numerous important dicotyledonous plants grown in the southwestern United States and northern Mexico. P. omnivora is notoriously difficult to isolate from infected plants; therefore methods for accurate and sensitive detection directly from symptomatic and asymptomatic plant samples are needed for disease diagnostics and pathogen identification. Primers were designed for P. omnivora based on consensus sequences of the nuclear ribosomal internal transcribed spacer (ITS) region of geographically representative isolates. Primers were compared against published P. omnivora sequences and validated against DNA from P. omnivora isolates and infected plant samples. The primer combinations amplified products from a range of P. omnivora isolates representative of known ITS haplotypes using standard end-point polymerase chain reaction (PCR) methodology. The assays detected P. omnivora from infected root samples of cotton (Gossypium hirsutum) and alfalfa (Medicago sativa). Healthy plants and other relevant root pathogens did not produce PCR products with the P. omnivora-specific primers. Primer pair PO2F/PO2R was the most sensitive in end-point PCR assays and is recommended for use for pathogen identification from mycelial tissue and infected plant materials when quantitative PCR (qPCR) is not available. Primer pair PO3F/PO2R was highly sensitive (1 fg) when used in SYBR Green qPCR assays and is recommended for screening of plant materials potentially infected by P. omnivora or samples with suboptimal DNA quality. The described PCR-based detection methods will be useful for rapid and sensitive screening of infected plants in diagnostic laboratories, plant health inspections, and plant breeding programs.

4.
Mol Ecol ; 22(4): 1092-104, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23189975

RESUMO

Genetic diversity of contemporary domesticated species is shaped by both natural and human-driven processes. However, until now, little is known about how domestication has imprinted the variation of fruit tree species. In this study, we reconstruct the recent evolutionary history of the domesticated almond tree, Prunus dulcis, around the Mediterranean basin, using a combination of nuclear and chloroplast microsatellites [i.e. simple sequence repeat (SSRs)] to investigate patterns of genetic diversity. Whereas conservative chloroplast SSRs show a widespread haplotype and rare locally distributed variants, nuclear SSRs show a pattern of isolation by distance with clines of diversity from the East to the West of the Mediterranean basin, while Bayesian genetic clustering reveals a substantial longitudinal genetic structure. Both kinds of markers thus support a single domestication event, in the eastern side of the Mediterranean basin. In addition, model-based estimation of the timing of genetic divergence among those clusters is estimated sometime during the Holocene, a result that is compatible with human-mediated dispersal of almond tree out of its centre of origin. Still, the detection of region-specific alleles suggests that gene flow from relictual wild preglacial populations (in North Africa) or from wild counterparts (in the Near East) could account for a fraction of the diversity observed.


Assuntos
Evolução Molecular , Variação Genética , Prunus/genética , Teorema de Bayes , Análise por Conglomerados , DNA de Cloroplastos/genética , DNA de Plantas/genética , Haplótipos , Região do Mediterrâneo , Repetições de Microssatélites , Modelos Genéticos , Filogeografia , Análise de Sequência de DNA
5.
J Child Neurol ; 15(3): 172-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10757473

RESUMO

A heterogeneous group of patients with congenital muscular dystrophy associated with clinical or radiologic central nervous system involvement other than the severe classic form with merosin deficiency, muscle-eye-brain disease, and Walker-Warburg syndrome is described. A probable hereditary or familial occurrence could be suggested in all patients. One merosin-positive patient presented severe motor incapacity and cerebral atrophy without any clinical manifestation of central nervous system involvement. A second patient, also merosin-positive, had moderate motor and mental handicap, and epilepsy with no changes in neuroimaging. A third patient, found to have partial merosin deficiency by muscle biopsy, manifested severe psychomotor retardation and cerebral atrophy with foci of abnormal white-matter signal on magnetic resonance imaging. Finally, two merosin-positive siblings with microcephaly, mental retardation, and an incapacitating progressive neuromuscular course, exhibited cataracts without defects of neuronal migration or brain malformation. This report emphasizes the broad clinical spectrum and heterogeneity of merosin-positive congenital muscular dystrophy with associated central nervous system involvement, and illustrates the importance of further studies on clinical, immunohistochemical, and genetic grounds for identifying new subsets of congenital muscular dystrophy.


Assuntos
Encefalopatias/genética , Distrofias Musculares/genética , Atrofia , Encéfalo/patologia , Encefalopatias/diagnóstico , Criança , Pré-Escolar , Diagnóstico Diferencial , Distrofina/genética , Feminino , Seguimentos , Humanos , Lactente , Laminina/genética , Imageamento por Ressonância Magnética , Masculino , Músculo Esquelético/patologia , Distrofias Musculares/diagnóstico , Distrofias Musculares/patologia , Exame Neurológico
6.
Rev. chil. pediatr ; 64(6): 359-63, nov.-dic. 1993. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-131732

RESUMO

Se midieron calcemia, fosfemia, fosfatasas alcalinas y la fracción ósea de éstas en 10 recién nacidos de pretérmino entre 28 y 30 semanas de edad gestacional al nacer y a las 32, 36 y 44 semanas de edad gestacional corregida. Además se les determinó densidad ósea por densitometría de doble fotón y radiografía esquelética a las 36 y 44 semanas de edad gestacional corregida. Los resultados obtenidos fueron comparados con un grupo control de otros 10 recien nacidos de 36 a 37 semanas de edad gestacional. Calcemias y fosfemias no mostraron diferencias significativas entre ambos grupos. Sin embargo, las concentraciones séricas de fosfatasas alcalinas a las 32 36 y 44 semanas fueron significativamente distintas que en el grupo control (p<0,0001). La disminución de la densidad ósea en los niños prematuros (p<0,0001) se correlacionó con la elevación de las fosfatasas alcalinas r=0,77; p<0,0001). Casi el total de las fosfatasas alcalinas correspondía a la fracción ósea. La radiografía ósea no demostró alteraciones en los niños prematuros y sus controles, a pesar de los cambios descritos. Se demuestra la utilidad de la medición de FA como elemento diagnóstico en osteopenia y se corrobora la nula utilidad de la radiología ósea en la detección precoz de esta patología


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Fosfatase Alcalina , Doenças Ósseas Metabólicas/diagnóstico , Doenças do Prematuro/diagnóstico , Absorciometria de Fóton/métodos , Densidade Óssea , Cálcio/sangue , Densitometria , Recém-Nascido Prematuro
7.
Rev. chil. pediatr ; 64(2): 89-93, mar.-abr. 1993. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-119289

RESUMO

La osteopenia del pretérmino es cada vez más frecuente. Los métodos que actualmente se emplean para evaluarla son las fosfatasas alcalinas y la radiología, de poca precisión. La densitometría ósea es más precisa, pero hay poca experiencia con ella en el período neonatal. Con el objetivo de describir su aporte, en el diagnóstico de osteopenia del prematuro, se estudiaron 12 RN pretérmino de 25 a 30 semanas de gestación; y 10 RN sanos de 36 a 37 semanas de edad gestacional como controles. La medición se efectuó con densitómetro Norland 2600 de doble fotón. Se establecieron valores para TBM (contenido mineral óseo total), TBM/peso y BMD (densidad mineral ósea). El grupo control tuvo un peso promedio de 2.833 g la medición se efectuó en los primeros tres días de vida. En el grupo de estudio, la edad gestacional promedio fue 28,5 semanas, el peso al nacer 1.238 g, las mediciones se efectuaron a las 36 y 44 semanas postconcepcionales y su alimentación se hizo con leche materna o fórmula con 80 mg% de Ca y 40 mg% de P o ambas. Los RN controles tuvieron TBM 54,9ñ9,05 g, TBM/peso 19,65ñ1,98, y BMD 0,531ñ0,0061 g/cm* a la edad de tres días. En los RN pretérmino, a las 36 semanas los resultados fueron: TBM 27,75ñ6,6 g TBM/peso 10,86ñ1,6 y BMD 0,262ñ0,05 g/cm* y, a las 44 semanas, TBM 54,98ñ14,5 g (ns), TBM/peso 12,0ñ2,22 (p<0,0001), y BMD 0,346ñ0,06 g/cm* (p<0,0001). TBM/peso y BMD, a las 44 semanas persistían significativamente más bajos que el grupo control. La densitometría ósea es útil para demostrar la disminución del contenido mineral óseo en prematuros, seguir su evolución y controlar su manejo


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Doenças Ósseas Metabólicas/diagnóstico , Densitometria , Doenças do Prematuro/diagnóstico , Doenças Ósseas Metabólicas/dietoterapia , Estudos de Casos e Controles
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