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1.
BMC Cardiovasc Disord ; 24(1): 205, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600454

RESUMEN

BACKGROUND: Tuberculosis (TB) continues to be a major cause of death across sub-Saharan Africa (SSA). In parallel, non-communicable disease and especially cardiovascular disease (CVD) burden has increased substantially in the region. Cardiac manifestations of TB are well-recognised but the extent to which they co-exist with pulmonary TB (PTB) has not been systematically evaluated. The aim of this study is to improve understanding of the burden of cardiac pathology in PTB in those living with and without HIV in a high-burden setting. METHODS: This is a cross-sectional and natural history study to evaluate the burden and natural history of cardiac pathology in participants with PTB in Lusaka, Zambia, a high burden setting for TB and HIV. Participants with PTB, with and without HIV will be consecutively recruited alongside age- and sex-matched TB-uninfected comparators on a 2:1 basis. Participants will undergo baseline assessments to collect clinical, socio-demographic, functional, laboratory and TB disease impact data followed by point-of-care and standard echocardiography. Participants with PTB will undergo further repeat clinical and functional examination at two- and six months follow-up. Those with cardiac pathology at baseline will undergo repeat echocardiography at six months. DISCUSSION: The outcomes of the study are to a) determine the burden of cardiac pathology at TB diagnosis, b) describe its association with patient-defining risk factors and biochemical markers of cardiac injury and stretch and c) describe the natural history of cardiac pathology during the course of TB treatment.


Asunto(s)
Infecciones por VIH , Tuberculosis , Humanos , Zambia/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/complicaciones , Prevalencia , Estudios Transversales , Tuberculosis/complicaciones , Tuberculosis/epidemiología
2.
J Chem Phys ; 160(21)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38832744

RESUMEN

We study important aspects of shape selectivity effects of zeolites for hydroisomerization of linear alkanes, which produces a myriad of isomers, particularly for long chain hydrocarbons. To investigate the conditions for achieving an optimal yield of branched hydrocarbons, it is important to understand the role of chemical equilibrium in these reversible reactions. We conduct an extensive analysis of shape selectivity effects of different zeolites for the hydroisomerization of C7 and C8 isomers at chemical reaction equilibrium conditions. The reaction ensemble Monte Carlo method, coupled with grand-canonical Monte Carlo simulations, is commonly used for computing reaction equilibrium of heterogeneous reactions. The computational demands become prohibitive for a large number of reactions. We used a faster alternative in which reaction equilibrium is obtained by imposing chemical equilibrium in the gas phase and phase equilibrium between the gas phase components and the adsorbed phase counterparts. This effectively mimics the chemical equilibrium distribution in the adsorbed phase. Using Henry's law at infinite dilution and mixture adsorption isotherm models at elevated pressures, we calculate the adsorbed loadings in the zeolites. This study shows that zeolites with cage or channel-like structures exhibit significant differences in selectivity for alkane isomers. We also observe a minimal impact of pressure on the gas-phase equilibrium of these reactions at typical experimental reaction temperatures 400-700K. This study marks initial strides in understanding the reaction product distribution for long-chain alkanes.

3.
Int J Equity Health ; 22(1): 205, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37794428

RESUMEN

BACKGROUND: Sars-CoV-2, the causative agent of COVID-19, has led to more than 226,000 deaths in the UK and multiple risk factors for mortality including age, sex and deprivation have been identified. This study aimed to identify which individual indicators of the Scottish Index of Multiple Deprivation (SIMD), an area-based deprivation index, were predictive of mortality. METHODS: This was a prospective cohort study of anonymised electronic health records of 710 consecutive patients hospitalised with Covid-19 disease between March and June 2020 in the Lothian Region of Southeast Scotland. Data sources included automatically extracted data from national electronic platforms and manually extracted data from individual admission records. Exposure variables of interest were SIMD quintiles and 12 indicators of deprivation deemed clinically relevant selected from the SIMD. Our primary outcome was mortality. Age and sex adjusted univariable and multivariable analyses were used to determine measures of association between exposures of interest and the primary outcome. RESULTS: After adjusting for age and sex, we found an increased risk of mortality in the more deprived SIMD quintiles 1 and 3 (OR 1.75, CI 0.99-3.08, p = 0.053 and OR 2.17, CI 1.22-3.86, p = 0.009, respectively), but this association was not upheld in our multivariable model containing age, sex, Performance Status and clinical parameters of severity at admission. Of the 12 pre-selected indicators of deprivation, two were associated with greater mortality in our multivariable analysis: income deprivation rate categorised by quartile (Q4 (most deprived): 2.11 (1.20-3.77) p = 0.011)) and greater than expected hospitalisations due to alcohol per SIMD data zone (1.96 (1.28-3.00) p = 0.002)). CONCLUSIONS: SIMD as an aggregate measure of deprivation was not predictive of mortality in our cohort when other exposure measures were accounted for. However, we identified a two-fold increased risk of mortality in patients residing in areas with greater income-deprivation and/or number of hospitalisations due to alcohol. In areas where aggregate measures fail to capture pockets of deprivation, exploring the impact of specific SIMD indicators may be helpful in targeting resources to residents at risk of poorer outcomes from Covid-19.


Asunto(s)
COVID-19 , Humanos , Estudios de Cohortes , Factores Socioeconómicos , Estudios Prospectivos , SARS-CoV-2 , Escocia/epidemiología
4.
Plant J ; 107(2): 448-466, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33932060

RESUMEN

The xyloglucan endotransglucosylase/hydrolases (XTHs) are enzymes involved in cell wall assembly and growth regulation, cleaving and re-joining hemicellulose chains in the xyloglucan-cellulose network. Here, in a homologous system, we compare the secretion patterns of XTH11, XTH33 and XTH29, three members of the Arabidopsis thaliana XTH family, selected for the presence (XTH11 and XTH33) or absence (XTH29) of a signal peptide, and the presence of a transmembrane domain (XTH33). We show that XTH11 and XTH33 reached, respectively, the cell wall and plasma membrane through a conventional protein secretion (CPS) pathway, whereas XTH29 moves towards the apoplast following an unconventional protein secretion (UPS) mediated by exocyst-positive organelles (EXPOs). All XTHs share a common C-terminal functional domain (XET-C) that, for XTH29 and a restricted number of other XTHs (27, 28 and 30), continues with an extraterminal region (ETR) of 45 amino acids. We suggest that this region is necessary for the correct cell wall targeting of XTH29, as the ETR-truncated protein never reaches its final destination and is not recruited by EXPOs. Furthermore, quantitative real-time polymerase chain reaction analyses performed on 4-week-old Arabidopsis seedlings exposed to drought and heat stress suggest a different involvement of the three XTHs in cell wall remodeling under abiotic stress, evidencing stress-, organ- and time-dependent variations in the expression levels. Significantly, XTH29, codifying the only XTH that follows a UPS pathway, is highly upregulated with respect to XTH11 and XTH33, which code for CPS-secreted proteins.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Pared Celular/metabolismo , Glicosiltransferasas/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/fisiología , Brefeldino A/farmacología , Membrana Celular/metabolismo , Deshidratación , Glicosiltransferasas/fisiología , Aparato de Golgi/metabolismo , Respuesta al Choque Térmico , Sistemas de Translocación de Proteínas/efectos de los fármacos
5.
Environ Microbiol ; 21(1): 50-71, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30246283

RESUMEN

The quest to discover the variety of ecological niches inhabited by Saccharomyces cerevisiae has led to research in areas as diverse as wineries, oak trees and insect guts. The discovery of fungal communities in the human gastrointestinal tract suggested the host's gut as a potential reservoir for yeast adaptation. Here, we report the existence of yeast populations associated with the human gut (HG) that differ from those isolated from other human body sites. Phylogenetic analysis on 12 microsatellite loci and 1715 combined CDSs from whole-genome sequencing revealed three subclusters of HG strains with further evidence of clonal colonization within the host's gut. The presence of such subclusters was supported by other genomic features, such as copy number variation, absence/introgressions of CDSs and relative polymorphism frequency. Functional analysis of CDSs specific of the different subclusters suggested possible alterations in cell wall composition and sporulation features. The phenotypic analysis combined with immunological profiling of these strains further showed that sporulation was related with strain-specific genomic characteristics in the immune recognition pattern. We conclude that both genetic and environmental factors involved in cell wall remodelling and sporulation are the main drivers of adaptation in S. cerevisiae populations in the human gut.


Asunto(s)
Evolución Molecular , Microbioma Gastrointestinal , Tracto Gastrointestinal/microbiología , Insectos/microbiología , Saccharomyces cerevisiae/genética , Animales , Variaciones en el Número de Copia de ADN , Genoma Fúngico , Genómica , Humanos , Microbiota , Repeticiones de Microsatélite , Filogenia , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/aislamiento & purificación
6.
J Biol Chem ; 291(15): 7961-72, 2016 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-26887946

RESUMEN

The immune system is essential to maintain the mutualistic homeostatic interaction between the host and its micro- and mycobiota. Living as a commensal,Saccharomyces cerevisiaecould potentially shape the immune response in a significant way. We observed thatS. cerevisiaecells induce trained immunity in monocytes in a strain-dependent manner through enhanced TNFα and IL-6 production upon secondary stimulation with TLR ligands, as well as bacterial and fungal commensals. Differential chitin content accounts for the differences in training properties observed among strains, driving induction of trained immunity by increasing cytokine production and direct antimicrobial activity bothin vitroandin vivo These chitin-induced protective properties are intimately associated with its internalization, identifying a critical role of phagosome acidification to facilitate microbial digestion. This study reveals how commensal and passenger microorganisms could be important in promoting health and preventing mucosal diseases by modulating host defense toward pathogens and thus influencing the host microbiota-immune system interactions.


Asunto(s)
Quitina/inmunología , Inmunidad Innata , Monocitos/microbiología , Saccharomyces cerevisiae/inmunología , Animales , Pared Celular/inmunología , Humanos , Interleucina-6/inmunología , Ratones Endogámicos C57BL , Monocitos/inmunología , Fagocitosis , Factor de Necrosis Tumoral alfa/inmunología
7.
J Assist Reprod Genet ; 34(12): 1699-1708, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28929253

RESUMEN

PURPOSE: The purpose of this study was to develop a novel one-step ICSI approach to select sperm with better chromatin maturity than the conventional method. METHODS: This was a pilot diagnostic study, which prospectively recruited men during a 6-month period in a University-affiliated infertility centre. Forty consecutive semen samples were provided for analysis. The positive rheotaxis extended drop (PRED) was set up creating a pressure and viscosity gradient. Each semen sample was divided into four aliquots: one aliquot for density gradient centrifugation (DGC), two aliquots for PRED (fresh semen (PRED-FS) and processed semen (PRED-DGC)), and one aliquot as the control (FS). In PRED, a mean of 200 spermatozoa were collected consecutively without selection from the outlet reservoir. The aniline blue assay was used to assess chromatin immaturity. RESULTS: The mean channel length, measured from inlet to outlet, was 32.55 ± 0.86 mm, with a mean width of 1.04 ± 0.21 mm. In 82.5% of cases (33/40), at least 50 spermatozoa were captured between 15 and 30 min. Improved chromatin maturity after the DGC preparation and the PRED approach was observed in all samples. This was reflected by a mean reduction from 28.65 ± 8.97% uncondensed chromatin in the native ejaculates to 17.29 ± 7.72% in DGC and 0.89 ± 1.31% in the PRED approach (P < 0.01). CONCLUSIONS: The PRED method may improve the current ICSI technique by providing it with its own sperm selection process. ICSI would probably become an even more complete technique comprising selection, capture and injection of the male gamete.


Asunto(s)
Cromatina/química , Hidrodinámica , Reología , Inyecciones de Esperma Intracitoplasmáticas , Motilidad Espermática/fisiología , Espermatozoides/fisiología , Adulto , Centrifugación por Gradiente de Densidad , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Espermatozoides/citología , Adulto Joven
8.
Phys Rev Lett ; 115(22): 222501, 2015 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-26650298

RESUMEN

The energy spacing between the spin-doublet bound state of _{Λ}^{4}He(1^{+},0^{+}) was determined to be 1406±2±2 keV, by measuring γ rays for the 1^{+}→0^{+} transition with a high efficiency germanium detector array in coincidence with the ^{4}He(K^{-},π^{-})_{Λ}^{4}He reaction at J-PARC. In comparison to the corresponding energy spacing in the mirror hypernucleus _{Λ}^{4}H, the present result clearly indicates the existence of charge symmetry breaking (CSB) in ΛN interaction. By combining the energy spacings with the known ground-state binding energies, it is also found that the CSB effect is large in the 0^{+} ground state but is vanishingly small in the 1^{+} excited state, demonstrating that the ΛN CSB interaction has spin dependence.

10.
Am J Bot ; 101(6): 1002-1012, 2014 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-24920764

RESUMEN

• Premise of the study: Tropical regions have high species diversity, and polyploidization is a major mechanism of speciation in plants. However, few cases of natural polyploidy have been reported in tropical regions. Lippia alba, is a tropical, aromatic shrub with a wide distribution, extensive morphological plasticity, and several chemotypes. The species has long been recognized as a diploid with 2n = 30 chromosomes. Recently, two variations in chromosome number (2n = 60; 2n = 12-60) have been reported, suggesting the occurrence of polyploidy within the species.• Methods: Flow cytometry was used to investigate the genome size in 106 accessions from 14 Brazilian States. Conventional and molecular cytogenetic techniques and pollen viability analysis were employed to characterize each chromosome number observed.• Key results: The DNA 1C-value varied from 1.17 to 3.45 pg, showing a large variation in genome size. Five distinct chromosome numbers were observed (2n = 30, 38, 45, 60, 90); three are cytogenetically described here for the first time. The 5S rDNA signals varied proportionally according to each chromosome number, but 45S rDNA sites did not. High rates of meiotic irregularity were observed, mainly in cytotypes with higher chromosome numbers.• Conclusions: The data provide new support for the occurrence of a polyploid series in Lippia alba. We provide a hypothesis for how this complex may have arisen. Other cryptic polyploid complexes may remain undiscovered in tropical regions.


Asunto(s)
Lippia/genética , Poliploidía , Brasil , Cromosomas de las Plantas
12.
ScientificWorldJournal ; 2014: 792420, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24558328

RESUMEN

Cellulose synthase-like (Csl) genes are believed to encode enzymes for the synthesis of cell wall matrix polysaccharides. The subfamily of CslA is putatively involved in the biosynthesis of ß -mannans. Here we report a study on the cellular localization and the enzyme activity of an Arabidopsis CslA family member, AtCslA2. We show that the fluorescent protein fusion AtCslA2-GFP, transiently expressed in tobacco leaf protoplasts, is synthesized in the ER and it accumulates in the Golgi stacks. The chimera is inserted in the Golgi membrane and is functional since membrane preparations obtained by transformed protoplasts carry out the in vitro synthesis of a 14C-mannan starting from GDP-D-[U-14C]mannose as substrate. The enzyme specific activity is increased by approximately 38% in the transformed protoplasts with respect to wild-type. Preliminary tests with proteinase K, biochemical data, and TM domain predictions suggest that the catalytic site of AtCslA2 faces the Golgi lumen.


Asunto(s)
Arabidopsis , Quimera , Colorantes Fluorescentes/química , Glucosiltransferasas/química , Red trans-Golgi/química , Arabidopsis/enzimología , Fenómenos Bioquímicos , Quimera/metabolismo , Colorantes Fluorescentes/metabolismo , Glucosiltransferasas/metabolismo , Hojas de la Planta/enzimología , Nicotiana/enzimología , Red trans-Golgi/enzimología
13.
BMC Genomics ; 14: 781, 2013 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-24219562

RESUMEN

BACKGROUND: Many fruits, including watermelon, are proficient in carotenoid accumulation during ripening. While most genes encoding steps in the carotenoid biosynthetic pathway have been cloned, few transcriptional regulators of these genes have been defined to date. Here we describe the identification of a set of putative carotenoid-related transcription factors resulting from fresh watermelon carotenoid and transcriptome analysis during fruit development and ripening. Our goal is to both clarify the expression profiles of carotenoid pathway genes and to identify candidate regulators and molecular targets for crop improvement. RESULTS: Total carotenoids progressively increased during fruit ripening up to ~55 µg g(-1) fw in red-ripe fruits. Trans-lycopene was the carotenoid that contributed most to this increase. Many of the genes related to carotenoid metabolism displayed changing expression levels during fruit ripening generating a metabolic flux toward carotenoid synthesis. Constitutive low expression of lycopene cyclase genes resulted in lycopene accumulation. RNA-seq expression profiling of watermelon fruit development yielded a set of transcription factors whose expression was correlated with ripening and carotenoid accumulation. Nineteen putative transcription factor genes from watermelon and homologous to tomato carotenoid-associated genes were identified. Among these, six were differentially expressed in the flesh of both species during fruit development and ripening. CONCLUSIONS: Taken together the data suggest that, while the regulation of a common set of metabolic genes likely influences carotenoid synthesis and accumulation in watermelon and tomato fruits during development and ripening, specific and limiting regulators may differ between climacteric and non-climacteric fruits, possibly related to their differential susceptibility to and use of ethylene during ripening.


Asunto(s)
Carotenoides/genética , Citrullus/crecimiento & desarrollo , Frutas/crecimiento & desarrollo , Redes y Vías Metabólicas/genética , Carotenoides/metabolismo , Citrullus/efectos de los fármacos , Citrullus/metabolismo , Etilenos/farmacología , Frutas/efectos de los fármacos , Frutas/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Licopeno , Redes y Vías Metabólicas/efectos de los fármacos , Proteínas de Plantas/biosíntesis , Plantas Modificadas Genéticamente
14.
Plant J ; 65(2): 295-308, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21223393

RESUMEN

The secretory pathway in plants involves sustained traffic to the cell wall, as matrix components, polysaccharides and proteins reach the cell wall through the endomembrane system. We studied the secretion pattern of cell-wall proteins in tobacco protoplasts and leaf epidermal cells using fluorescent forms of a pectin methylesterase inhibitor protein (PMEI1) and a polygalacturonase inhibitor protein (PGIP2). The two most representative protein fusions, secGFP-PMEI1 and PGIP2-GFP, reached the cell wall by passing through ER and Golgi stacks but using distinct mechanisms. secGFP-PMEI1 was linked to a glycosylphosphatidylinositol (GPI) anchor and stably accumulated in the cell wall, regulating the activity of the endogenous pectin methylesterases (PMEs) that are constitutively present in this compartment. A mannosamine-induced non-GPI-anchored form of PMEI1 as well as a form (PMEI1-GFP) that was unable to bind membranes failed to reach the cell wall, and accumulated in the Golgi stacks. In contrast, PGIP2-GFP moved as a soluble cargo protein along the secretory pathway, but was not stably retained in the cell wall, due to internalization to an endosomal compartment and eventually the vacuole. Stable localization of PGIP2 in the wall was observed only in the presence of a specific fungal endopolygalacturonase ligand in the cell wall. Both secGFP-PMEI1 and PGIP2-GFP sorting were distinguishable from that of a secreted GFP, suggesting that rigorous and more complex controls than the simple mechanism of bulk flow are the basis of cell-wall growth and differentiation.


Asunto(s)
Pared Celular/metabolismo , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Poligalacturonasa/metabolismo , Biomarcadores , Membrana Celular/metabolismo , Retículo Endoplásmico/metabolismo , Endosomas/metabolismo , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/metabolismo , Proteínas Ligadas a GPI/metabolismo , Aparato de Golgi/metabolismo , Hexosaminas/efectos adversos , Hexosaminas/metabolismo , Mutación , Proteínas de Plantas/farmacología , Plantas Modificadas Genéticamente , Poligalacturonasa/antagonistas & inhibidores , Unión Proteica , Estabilidad Proteica , Transporte de Proteínas , Protoplastos/metabolismo , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Nicotiana/citología , Nicotiana/genética
15.
J Urol ; 188(1): 253-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22595063

RESUMEN

PURPOSE: Williams-Beuren syndrome is a genomic disorder caused by a hemizygous contiguous gene deletion on chromosome 7q11.23. Lower urinary tract symptoms are common in children with Williams-Beuren syndrome. However, there are few data on the management of voiding symptoms in this population. We report our experience using oxybutynin to treat urinary symptoms in children with Williams-Beuren syndrome. MATERIALS AND METHODS: We prospectively analyzed 42 patients with Williams-Beuren syndrome and significant lower urinary tract symptoms due to detrusor overactivity diagnosed on urodynamics in a 12-week, open-label study. Urological assessment included symptomatic evaluation, the impact of lower urinary tract symptoms on quality of life, frequency-volume chart, urodynamics and urinary tract sonography. After 12 weeks of treatment with 0.6 mg/kg oxybutynin per day given in 3 daily doses, patients were assessed for treatment efficacy and side effects. RESULTS: A total of 17 girls and 19 boys completed medical therapy and were assessed at 12 weeks. Mean ± SD patient age was 9.2 ± 4.3 years (range 3 to 18). The most common urinary complaint was urgency, which occurred in 31 patients (86.1%), followed by urge incontinence, which was seen in 29 (80.5%). Compared to baseline, urinary symptoms were substantially improved. The negative impact of storage symptoms on quality of life was significantly decreased from a mean ± SD of 3.3 ± 1.7 to 0.5 ± 0.9 (p <0.001). Mean ± SD maximum urinary flow improved from 14.2 ± 15.0 to 20.5 ± 6.4 ml per second (p <0.001). CONCLUSIONS: A total of 12 weeks of therapy with 0.6 mg/kg oxybutynin daily resulted in improvement of lower urinary tract symptoms, quality of life and maximum flow rate in most patients with Williams-Beuren syndrome.


Asunto(s)
Ácidos Mandélicos/administración & dosificación , Antagonistas Muscarínicos/administración & dosificación , Trastornos Urinarios/tratamiento farmacológico , Urodinámica/efectos de los fármacos , Síndrome de Williams/complicaciones , Adolescente , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Calidad de Vida , Resultado del Tratamiento , Trastornos Urinarios/etiología , Trastornos Urinarios/fisiopatología , Síndrome de Williams/fisiopatología
16.
Phys Rev Lett ; 108(4): 042501, 2012 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-22400828

RESUMEN

Evidence for the neutron-rich hypernucleus (Λ)(6)H is presented from the FINUDA experiment at DAΦNE, Frascati, studying (π+,π-) pairs in coincidence from the K(stop)(-) + (6)Li →(Λ)(6)H + π+ production reaction followed by (Λ)(6)H → (6)He + π- weak decay. The production rate of (Λ)(6) undergoing this two-body π- decay is determined to be (2.9 ± 2.0) × 10(-6)/K(stop)(-). Its binding energy, evaluated jointly from production and decay, is BΛ((Λ)(6)H) = (4.0 ± 1.1) MeV with respect to (5)H+Λ. A systematic difference of (0.98 ± 0.74) MeV between BΛ values derived separately from decay and from production is tentatively assigned to the (Λ)(6)H 0(g.s.)(+) → 1+ excitation.

17.
Phys Rev Lett ; 109(13): 132002, 2012 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-23030084

RESUMEN

The Θ(+) pentaquark baryon was searched for via the π(-)p→K(-)X reaction with a missing mass resolution of 1.4 MeV/c(2) (FWHM) at the Japan Proton Accelerator Research Complex (J-PARC). π(-) meson beams were incident on the liquid hydrogen target with a beam momentum of 1.92 GeV/c. No peak structure corresponding to the Θ(+) mass was observed. The upper limit of the production cross section averaged over the scattering angle of 2° to 15° in the laboratory frame is obtained to be 0.26 µb/sr in the mass region of 1.51-1.55 GeV/c(2). The upper limit of the Θ(+) decay width is obtained to be 0.72 and 3.1 MeV for J(Θ)(P)=1/2(+) and J(Θ)(P)=1/2(-), respectively, using the effective Lagrangian approach.

18.
Hortic Res ; 9: uhac084, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669706

RESUMEN

Lycopene content in tomato fruit is largely under genetic control and varies greatly among genotypes. Continued improvement of lycopene content in elite varieties with conventional breeding has become challenging, in part because little is known about the underlying molecular mechanisms in high-lycopene tomatoes (HLYs). We collected 42 HLYs with different genetic backgrounds worldwide. High-performance liquid chromatography (HPLC) analysis revealed lycopene contents differed among the positive control wild tomato Solanum pimpinellifolium, HLYs, the normal lycopene cultivar "Moneymaker", and the non-lycopene cultivar NC 1Y at the pink and red ripe stages. Real-time RT-PCR analysis of expression of the 25 carotenoid biosynthesis pathway genes of each genotype showed a significantly higher expression in nine upstream genes (GGPPS1, GGPPS2, GGPPS3, TPT1, SSU II, PSY2, ZDS, CrtISO and CrtISO-L1 but not the well-studied PSY1, PDS and Z-ISO) at the breaker and/or red ripe stages in HLYs compared to Moneymaker, indicating a higher metabolic flux flow into carotenoid biosynthesis pathway in HLYs. Further conversion of lycopene to carotenes may be prevented via the two downstream genes (ß-LCY2 and ε-LCY), which had low-abundance transcripts at either or both stages. Additionally, the significantly higher expression of four downstream genes (BCH1, ZEP, VDE, and CYP97C11) at either or both ripeness stages leads to significantly lower fruit lycopene content in HLYs than in the wild tomato. This is the first systematic investigation of the role of the complete pathway genes in regulating fruit lycopene biosynthesis across many HLYs, and enables tomato breeding and gene editing for increased fruit lycopene content.

19.
Biology (Basel) ; 11(8)2022 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-36009766

RESUMEN

Improved cellulose biosynthesis and plant biomass represent important economic targets for several biotechnological applications including bioenergy and biofuel production. The attempts to increase the biosynthesis of cellulose by overexpressing CesAs proteins, components of the cellulose synthase complex, has not always produced consistent results. Analyses of morphological and molecular data and of the chemical composition of cell walls showed that tobacco plants (F31 line), stably expressing the Arabidopsis CesA6 fused to GFP, exhibits a "giant" phenotype with no apparent other morphological aberrations. In the F31 line, all evaluated growth parameters, such as stem and root length, leaf size, and lignified secondary xylem, were significantly higher than in wt. Furthermore, F31 line exhibited increased flower and seed number, and an advance of about 20 days in the anthesis. In the leaves of F31 seedlings, the expression of primary CesAs (NtCesA1, NtCesA3, and NtCesA6) was enhanced, as well as of proteins involved in the biosynthesis of non-cellulosic polysaccharides (xyloglucans and galacturonans, NtXyl4, NtGal10), cell wall remodeling (NtExp11 and XTHs), and cell expansion (NtPIP1.1 and NtPIP2.7). While in leaves the expression level of all secondary cell wall CesAs (NtCesA4, NtCesA7, and NtCesA8) did not change significantly, both primary and secondary CesAs were differentially expressed in the stem. The amount of cellulose and matrix polysaccharides significantly increased in the F31 seedlings with no differences in pectin and hemicellulose glycosyl composition. Our results highlight the potentiality to overexpress primary CesAs in tobacco plants to enhance cellulose synthesis and biomass production.

20.
Primates ; 63(4): 335-342, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35648246

RESUMEN

Primate thanatology, or the study of primate responses to dying and death, has become increasingly relevant in recent years. However, the number of reports remains small and the quality of published records is highly variable. Here, we extend the literature on comparative thanatology with observations on a population of the northern muriqui (Brachyteles hypoxanthus). We compiled all seven cases of muriqui responses to dead, dying, or abandoned infants observed by trained researchers of the Muriqui Project of Caratinga between 1998 and 2020. Four different adult females were observed carrying their dead offspring (n = 4) and one of these females was also observed carrying her dead grand-offspring (n = 1). Five of the seven cases involved dead newborns, one involved a newborn abandoned by its mother on the forest floor, and one involved a 1.6-year-old infant that was visibly ill and died after its mother left it on the ground. Dead newborns were carried for 1-3 days, and all cases occurred during the dry season months. No other age-sex classes were observed to interact with the dead or dying immatures. Our observations are consistent with hypotheses concerning the predominance of dead-infant carrying in other primates, and with the effects of climate on rates of corpse disintegration. They also show the value of long-term studies for obtaining and understanding anecdotal records of rare behavior.


Asunto(s)
Atelinae , Conducta Animal , Tanatología , Animales , Animales Recién Nacidos , Atelinae/fisiología , Atelinae/psicología , Clima , Muerte , Femenino , Humanos , Madres/psicología
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