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1.
Antimicrob Agents Chemother ; 68(1): e0109623, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38038476

RESUMO

Results from clinical strains and knockouts of the H37Rv and CDC1551 laboratory strains demonstrated that ndh (Rv1854c) is not a resistance-conferring gene for isoniazid, ethionamide, delamanid, or pretomanid in Mycobacterium tuberculosis. This difference in the susceptibility to NAD-adduct-forming drugs compared with other mycobacteria may be driven by differences in the absolute intrabacterial NADH concentration.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Isoniazida/farmacologia , Etionamida/farmacologia , Mycobacterium tuberculosis/genética , Antituberculosos/farmacologia , Proteínas de Bactérias/genética , Mutação , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
2.
BMC Infect Dis ; 22(1): 437, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524232

RESUMO

BACKGROUND: Molecular mechanisms determining the transmission and prevalence of drug resistant tuberculosis (DR-TB) in Papua New Guinea (PNG) are poorly understood. We used genomic and drug susceptibility data to explore the evolutionary history, temporal acquisition of resistance and transmission dynamics of DR-TB across PNG. METHODS: We performed whole genome sequencing on isolates from Central Public Health Laboratory, PNG, collected 2017-2019. Data analysis was done on a composite dataset that also included 100 genomes previously sequenced from Daru, PNG (2012-2015). RESULTS: Sampled isolates represented 14 of the 22 PNG provinces, the majority (66/94; 70%) came from the National Capital District (NCD). In the composite dataset, 91% of strains were Beijing 2.2.1.1, identified in 13 provinces. Phylogenetic tree of Beijing strains revealed two clades, Daru dominant clade (A) and NCD dominant clade (B). Multi-drug resistance (MDR) was repeatedly and independently acquired, with the first MDR cases in both clades noted to have emerged in the early 1990s, while fluoroquinolone resistance emerged in 2009 (95% highest posterior density 2000-2016). We identified the presence of a frameshift mutation within Rv0678 (p.Asp47fs) which has been suggested to confer resistance to bedaquiline, despite no known exposure to the drug. Overall genomic clustering was significantly associated with rpoC compensatory and inhA promoter mutations (p < 0.001), with high percentage of most genomic clusters (12/14) identified in NCD, reflecting its role as a potential national amplifier. CONCLUSIONS: The acquisition and evolution of drug resistance among the major clades of Beijing strain threaten the success of DR-TB treatment in PNG. With continued transmission of this strain in PNG, genotypic drug resistance surveillance using whole genome sequencing is essential for improved public health response to outbreaks. With occurrence of resistance to newer drugs such as bedaquiline, knowledge of full drug resistance profiles will be important for optimal treatment selection.


Assuntos
Mycobacterium tuberculosis , Doenças não Transmissíveis , Tuberculose dos Linfonodos , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Papua Nova Guiné/epidemiologia , Filogenia , Tuberculose dos Linfonodos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
3.
Surg Endosc ; 36(6): 4349-4358, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34724580

RESUMO

BACKGROUND: Studies to date show contrasting conclusions when comparing intracorporeal and extracorporeal anastomoses for minimally invasive right colectomy. Large multi-center prospective studies comparing perioperative outcomes between these two techniques are needed. The purpose of this study was to compare intracorporeal and extracorporeal anastomoses outcomes for robotic assisted and laparoscopic right colectomy. METHODS: Multi-center, prospective, observational study of patients with malignant or benign disease scheduled for laparoscopic or robotic-assisted right colectomy. Outcomes included conversion rate, gastrointestinal recovery, and complication rates. RESULTS: There were 280 patients: 156 in the robotic assisted and laparoscopic intracorporeal anastomosis (IA) group and 124 in the robotic assisted and laparoscopic extracorporeal anastomosis (EA) group. The EA group was older (mean age 67 vs. 65 years, p = 0.05) and had fewer white (81% vs. 90%, p = 0.05) and Hispanic (2% vs. 12%, p = 0.003) patients. The EA group had more patients with comorbidities (82% vs. 72%, p = 0.04) while there was no significant difference in individual comorbidities between groups. IA was associated with fewer conversions to open and hand-assisted laparoscopic approaches (p = 0.007), shorter extraction site incision length (4.9 vs. 6.2 cm; p ≤ 0.0001), and longer operative time (156.9 vs. 118.2 min). Postoperatively, patients with IA had shorter time to first flatus, (1.5 vs. 1.8 days; p ≤ 0.0001), time to first bowel movement (1.6 vs. 2.0 days; p = 0.0005), time to resume soft/regular diet (29.0 vs. 37.5 h; p = 0.0014), and shorter length of hospital stay (median, 3 vs. 4 days; p ≤ 0.0001). Postoperative complication rates were comparable between groups. CONCLUSION: In this prospective, multi-center study of minimally invasive right colectomy across 20 institutions, IA was associated with significant improvements in conversion rates, return of bowel function, and shorter hospital stay, as well as significantly longer operative times compared to EA. These data validate current efforts to increase training and adoption of the IA technique for minimally invasive right colectomy.


Assuntos
Neoplasias do Colo , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Idoso , Anastomose Cirúrgica/métodos , Colectomia/métodos , Neoplasias do Colo/cirurgia , Humanos , Laparoscopia/métodos , Duração da Cirurgia , Estudos Prospectivos , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Resultado do Tratamento
4.
Emerg Infect Dis ; 25(3): 406-415, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30789135

RESUMO

In this retrospective study, we used whole-genome sequencing (WGS) to delineate transmission dynamics, characterize drug-resistance markers, and identify risk factors of transmission among Papua New Guinea residents of the Torres Strait Protected Zone (TSPZ) who had tuberculosis diagnoses during 2010-2015. Of 117 isolates collected, we could acquire WGS data for 100; 79 were Beijing sublineage 2.2.1.1, which was associated with active transmission (odds ratio 6.190, 95% CI 2.221-18.077). Strains were distributed widely throughout the TSPZ. Clustering occurred more often within than between villages (p = 0.0013). Including 4 multidrug-resistant tuberculosis isolates from Australia citizens epidemiologically linked to the TSPZ into the transmission network analysis revealed 2 probable cross-border transmission events. All multidrug-resistant isolates (33/104) belonged to Beijing sublineage 2.2.1.1 and had high-level isoniazid and ethionamide co-resistance; 2 isolates were extensively drug resistant. Including WGS in regional surveillance could improve tuberculosis transmission tracking and control strategies within the TSPZ.


Assuntos
Emigração e Imigração , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Antituberculosos/farmacologia , Austrália/epidemiologia , Técnicas de Tipagem Bacteriana , Evolução Molecular , Genótipo , Geografia , História do Século XXI , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Papua Nova Guiné/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/história , Sequenciamento Completo do Genoma
5.
Intern Med J ; 47(7): 820-823, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28677313

RESUMO

Disseminated Mycobacterium bovis is an uncommon side-effect of intravesical Bacillus Calmette-Guérin (BCG) therapy that may be mediated through Mycobacteraemia. This case report, of a 77-year-old man with a history of intravesical BCG therapy and recent cardiac surgery, highlights the need for patients with similar features on history, presenting with generalised symptoms, to have mycobacterial cultures included in their workup.


Assuntos
Vacina BCG/efeitos adversos , Mycobacterium bovis/isolamento & purificação , Tuberculose/induzido quimicamente , Neoplasias da Bexiga Urinária/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Administração Intravesical , Idoso , Vacina BCG/administração & dosagem , Humanos , Masculino , Fatores de Tempo , Tuberculose/diagnóstico , Tuberculose/etiologia , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/diagnóstico
6.
J Sci Food Agric ; 96(13): 4351-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26804312

RESUMO

BACKGROUND: Nano-size and wide-range solubility of amphiphilic polymers (having both hydrophilic and hydrophobic blocks) can improve uniformity in seed coatings. An investigation was carried out to assess the positive effect of amphiphilic polymers over hydrophilic or hydrophobic polymers as seed coating agents and pesticide carriers. RESULTS: Amphiphilic polymers with 127.5-354 nm micelle size were synthesized in the laboratory using polyethylene glycols and aliphatic di-acids. After 6 months of storage, germination of uncoated soybean seeds decreased drastically from 97.80 to 81.55%, while polymer-coated seeds showed 89.44-95.92% germination. Similarly, vigour index-1 was reduced from 3841.10 to 2813.06 for control seeds but ranged from 3375.59 to 3844.60 for polymer-coated seeds after 6 months. The developed imidacloprid formulations retained more pesticide on soybean seed coatings than did a commercial formulation (Gaucho(®) 600 FS). The time taken for 50% release of imidacloprid from seed coatings in water was 7.12-9.11 h for the developed formulations and 0.41 h for the commercial formulation. CONCLUSION: Nano-range amphiphilic polymers can be used to protect soybean seeds from ageing. Formulations as seed treatments may produce improved and sustained efficacy with minimum environmental contamination. © 2016 Society of Chemical Industry.


Assuntos
Agroquímicos/química , Glycine max/química , Imidazóis/química , Inseticidas/química , Nanoestruturas/química , Nitrocompostos/química , Sementes/química , Tensoativos/química , Agroquímicos/efeitos adversos , Algoritmos , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Ácidos Dicarboxílicos/efeitos adversos , Ácidos Dicarboxílicos/química , Poluição Ambiental/prevenção & controle , Germinação , Interações Hidrofóbicas e Hidrofílicas , Índia , Micelas , Peso Molecular , Nanoestruturas/efeitos adversos , Neonicotinoides , Permeabilidade , Polietilenoglicóis/química , Sementes/crescimento & desenvolvimento , Solubilidade , Glycine max/crescimento & desenvolvimento , Propriedades de Superfície , Tensoativos/efeitos adversos , Fatores de Tempo , Água/análise
7.
Acta Chim Slov ; 62(1): 204-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25830977

RESUMO

Novel compounds of dimethyl- and dibutyltin(IV) with O-tolyl/benzyldithiocarbonates were successfully obtained by the reaction of Me(2)SnC(l2) and n-Bu(2)SnCl(2) with sodium salt of O-tolyl/benzyldithiocarbonates, [o-, m- and p-CH(3)C(6)H(4)OCS(2)Na and C(6)H(5)CH(2)OCS(2)Na], in 1:2 molar ratio in dry toluene. The structure of these newly synthesized complexes has been examined by elemental analysis, FT-IR, multinuclear NMR ((1)H, (13)C and (119)Sn) spectroscopy. The thermal behaviour of the complex (8) has been studied by TGA/DTA analysis. The complex (8), n-Bu2Sn(S2COCH2C6H5)2, crystallizes in the monoclinic space group C2/c, in which tin adopts a distorted octahedron or skew trapezoidal bipyramidal geometry accompanied by two n-butyl chains and the two dithiocarbonate ligands coordinated in an anisobidentate fashion. Antifungal activities against fungus Fusarium sp. of these organotin(IV) derivatives exhibited enhanced activity compared to the free ligands.

8.
BMC Microbiol ; 14: 307, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25476850

RESUMO

BACKGROUND: Papua New Guinea (PNG) is a high tuberculosis (TB) burden country of the WHO Western Pacific Region, but so far research on drug resistance (DR) and genotypes of Mycobacterium tuberculosis (M. tuberculosis) was only conducted in few provinces in the country. The aim of the present study was to obtain baseline data on the level of drug resistance and the genotypic diversity of circulating M. tuberculosis in additional provinces and to investigate the differences between three selected sites across PNG. RESULTS: Genotyping of 147 M. tuberculosis clinical isolates collected in Goroka, Eastern Highlands Province, in Alotau, Milne Bay Province and in Madang, Madang Province revealed three main lineages of M. tuberculosis: Lineage 4 (European-American lineage), Lineage 2 (East-Asian lineage) and Lineage 1 (Indo-Oceanic lineage). All three lineages were detected in all three sites, but the individual lineage compositions varied significantly between sites. In Madang Lineage 4 was the most prevalent lineage (76.6%), whereas in Goroka and Alotau Lineage 2 was dominating (60.5% and 84.4%, respectively) (p < 0.001). Overall, phenotypic drug susceptibility testing showed 10.8% resistance to at least one of the first-line drugs tested. Of all resistant strains (23/212) 30.4% were Streptomycin mono-resistant, 17.4% were Isoniazid mono-resistant and 13% were Rifampicin mono-resistant. Multi-drug resistant (MDR) TB was found in 2.8% of all tested cases (6/212). The highest amount of MDR TB was found in Alotau in Milne Bay Province (4.6%). CONCLUSION: A large number of drug resistant TB infections are present in the country and MDR TB has already been detected in all three surveyed regions of PNG, highlighting the importance of monitoring drug resistance and making it a high priority for the National Control Program. Due to the high prevalence of Lineage 2 in Milne Bay Province and given the frequent association of this lineage with drug resistance, monitoring of the latter should especially be scaled up in that province.


Assuntos
Farmacorresistência Bacteriana , Variação Genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/farmacologia , Feminino , Genótipo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem Molecular , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Papua Nova Guiné/epidemiologia , Tuberculose/epidemiologia , Adulto Jovem
9.
Opt Express ; 22(25): 30983-91, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25607047

RESUMO

p-type Sb-doped ZnO/i-CdZnO/n-type Ga-doped ZnO was grown by dual ion beam sputtering deposition system. Current-voltage characteristics of the heterojunction showed a diode-like rectifying behavior with a turn-on voltage of ~5 V. The diode yielded blue electroluminescence emissions at around 446 nm in forward biased condition at room temperature. The emission intensity increased with the increase of the injection current. A red shifting of the emission peak position was observed with the increment of ambient temperature, indicating a change of band gap of the CdZnO active layer with temperature in low-temperature measurement.

10.
BMC Infect Dis ; 14: 93, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24555577

RESUMO

BACKGROUND: The incidence and characteristics of tuberculosis (TB) in remote areas of Papua New Guinea (PNG) are largely unknown. The purpose of our study was to determine the incidence of TB in the Gulf Province of PNG and describe disease characteristics, co-morbidities and drug resistance profiles that could impact on disease outcomes and transmission. METHODS: Between March 2012 and June 2012, we prospectively collected data on 274 patients presenting to Kikori Hospital with a presumptive diagnosis of TB, and on hospital inpatients receiving TB treatment during the study period. Sputum was collected for microscopy, GeneXpert analysis, culture and genotyping of isolates. RESULTS: We estimate the incidence of TB in Kikori to be 1290 per 100,000 people (95% CI 1140 to 1460) in 2012. The proportion of TB patients co-infected with HIV was 1.9%. Three of 32 TB cases tested were rifampicin resistant. Typing of nine isolates demonstrated allelic diversity and most were related to Beijing strains. CONCLUSIONS: The incidence of TB in Kikori is one of the highest in the world and it is not driven by HIV co-infection. The high incidence and the presence of rifampicin resistant warrant urgent attention to mitigate substantial morbidity in the region.


Assuntos
Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose/microbiologia , Adolescente , Adulto , Alelos , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Coinfecção , Feminino , Genótipo , Infecções por HIV/complicações , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Papua Nova Guiné/epidemiologia , Estudos Prospectivos , Rifampina/uso terapêutico , Fatores de Risco , Escarro , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto Jovem
11.
Commun Dis Intell Q Rep ; 38(4): E369-75, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25631600

RESUMO

The Australian Mycobacterium Reference Laboratory Network collects and analyses laboratory data on new cases of disease caused by the Mycobacterium tuberculosis complex. In 2011, a total of 1,057 cases were identified bacteriologically; an annual reporting rate of 4.6 cases per 100,000 population. Eighteen children aged less than 15 years plus an additional 11 children from the Torres Strait Protected Zone had bacteriologically-confirmed tuberculosis. Results of in vitro drug susceptibility testing were available for 1,056 isolates for isoniazid, rifampicin, ethambutol, and pyrazinamide. A total of 107 (10.0%) isolates of M. tuberculosis were resistant to at least one of these anti-tuberculosis agents. Resistance to at least isoniazid and rifampicin (defined as multi-drug resistance, MDR) was detected in 25 (2.4%) isolates; 18 were from the respiratory tract (sputum n=14, bronchoscopy n=3, tissue n=1). Ten (55.6%) of the MDR-TB-positive sputum specimens were smear-positive, as was a single sample from a lymph node. Ten patients with MDR-TB were Papua New Guinea (PNG) nationals in the Torres Strait Protected Zone. If these PNG nationals are excluded from the analysis, the underlying MDR-TB rate in Australia was 1.4%. No cases of extensively drug-resistant TB (defined as MDR-TB with additional resistance to a fluoroquinolone and an injectable agent) were detected in 2011.


Assuntos
Farmacorresistência Bacteriana Múltipla , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Relatórios Anuais como Assunto , Antituberculosos/uso terapêutico , Austrália/epidemiologia , Criança , Pré-Escolar , Notificação de Doenças/estatística & dados numéricos , Emigração e Imigração , Monitoramento Epidemiológico , Feminino , Humanos , Incidência , Laboratórios , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Estudos Retrospectivos , Distribuição por Sexo , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/etnologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/etnologia , Tuberculose Pulmonar/microbiologia , População Branca
12.
Acta Chim Slov ; 61(4): 866-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551728

RESUMO

Diaryldithiophosphate complexes of mono- and dibutyltin(IV) corresponding to [(ArO)(2)PS(2)(n)Sn(nBu)xCl(4-x-n)] (Ar = o-CH(3)C(6)H(4), m-CH(3)C(6)H(4), p-CH(3)C(6)H(4), 4-Cl-3-CH(3)C(6)H(3), (3,5-CH(3))(2)C(6)H(3); n = 1, 2 for x = 1 and n = 2 for x = 2) were successfully isolated and characterized by elemental analyses, IR, multinuclear NMR ((1)H, (13)C, (31)P and (119)Sn) spectroscopy and X-ray analysis. The thermal properties of the complex [(3,5-CH(3))(2)C(6)H(3)O(2)PS(2)](2)Sn(nBu)(2) (12) have been examined by combined DTA/ DTG thermal analyses. Single crystal X-ray analysis of [(3,5-CH(3))(2)C(6)H(3)O(2)PS(2)](2)S(n)(nBu)(2) (12) revealed that two diaryldithiophosphate ions are coordinated to tin atom in an anisobidentate fashion through the sulfur atoms of each dithiophosphate moiety leading to distorted skew-trapezoidal bipyramidal geometry. The antifungal activity depicts that these complexes are active against fungus Penicillium chrysogenium.


Assuntos
Antifúngicos/química , Organofosfatos/química , Compostos Orgânicos de Estanho/química , Penicillium chrysogenum/efeitos dos fármacos , Antifúngicos/síntese química , Cristalografia por Raios X , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Organofosfatos/síntese química , Compostos Orgânicos de Estanho/síntese química
13.
J Mol Model ; 30(8): 250, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967840

RESUMO

CONTEXT: Carbon monoxide, also known as the "silent killer," is a colorless, odorless, tasteless, and non-irritable gas that, when inhaled, enters the bloodstream and lungs, binds with the hemoglobin, and blocks oxygen from reaching tissues and cells. In this work, the monolayer MoSe2-based CO gas sensors were designed using density functional theory calculation with several dopants including Al, Au, Pd, Ni, Cu, and P. Here, Cu and P were found to be the best dopants, with adsorption energies of -0.67 eV (Cu) and -0.54 eV (P) and recovery times of 1.66 s and 13.8 ms respectively. Cu conductivity for CO adsorption was found to be 2.74 times that of CO2 adsorption in the 1.0-2.26 eV range. P displayed the highest selectivity, followed by Pd and Ni. The dopants, Pd and Ni, were found suitable for building CO gas scavengers due to their high recovery times of 9.76 × 1020 s and 2.47 × 1011 s. Similarly, the adsorption of CO2 on doped monolayer MoSe2 was also investigated. In this study, it is found that monolayer MoSe2 could be employed to create high-performance CO sensors in a CO2-rich environment. METHOD: The electrical characteristics of all doped MoSe2 monolayers are obtained using a DFT calculation with the PBE-GGA method from the Quantum ESPRESSO package. The self-consistent field (SCF) computations were performed using a 7 × 7 × 1 k-point grid and a norm-conserving pseudo potential (NCPP) file. To determine electrical conductivity, the semi-classical version of Boltzmann transport theory, implemented in the Boltz Trap code, was used.

14.
Gene ; 895: 148001, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37977314

RESUMO

Demand for maize oil is progressively increasing due to its diverse industrial applications, aside from its primary role in human nutrition and animal feed. Oil content and composition are two crucial determinants of maize oil in the international market. As kernel oil in maize is a complex quantitative trait, improving this trait presents a challenge for plant breeders and biotechnologists. Here, we characterized a set of 292 diverse maize inbreds of both indigenous and exotic origin by exploiting functional polymorphism of the dgat1-2, fatb, ge2, and wri1a genes governing kernel oil in maize. Genotyping using gene-based functional markers revealed a lower frequencies of dgat1-2 (0.15) and fatb (0.12) mutant alleles and a higher frequencies of wild-type alleles (Dgat1-2: 0.85; fatB: 0.88). The favorable wri1a allele was conserved across genotypes, while its wild-type allele (WRI1a) was not detected. In contrast, none of the genotypes possessed the ge2 favorable allele. The frequency of favorable alleles of both dgat1-2 and fatb decreased to 0.03 when considered together. Furthermore, pairwise protein-protein interactions among target gene products were conducted to understand the effect of one protein on another and their responses to kernel oil through functional enrichments. Thus, the identified maize genotypes with dgat1-2, fatb, and wri1a favourable alleles, along with insights gained through the protein-protein association network, serve as prominent and unique genetic resources for high-oil maize breeding programs. This is the first comprehensive report on the functional characterization of diverse genotypes at the molecular and protein levels.


Assuntos
Óleo de Milho , Zea mays , Humanos , Zea mays/genética , Zea mays/metabolismo , Óleo de Milho/genética , Óleo de Milho/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Melhoramento Vegetal , Marcadores Genéticos , Alelos
15.
Front Plant Sci ; 14: 1284070, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023890

RESUMO

Introduction: The introgression of genetic material from one species to another through wide hybridization and repeated back-crossing, plays an important role in genetic modification and enriching the cultivated gene-pool with novel genetic variations. Okra (Abelmoschus esculentus [(L.) Moench)] is a popular vegetable crop with high dietary fibre and protein, rich in essential amino acids, lysine and tryptophan. The wild Abelmoschus genepool has many desirable traits like ornamental value, short internodal length, more number of productive branches, extended bearing, perennation tendency, reduced fruit length (more consumer preferred trait), high mucilage content (medicinal value), abiotic stress tolerances such as drought, high temperature and biotic stress resistances such as okra Yellow Vein Mosaic Virus (YVMV) and Enation Leaf Curl Virus (ELCV) diseases. The repeated use of elite breeding lines led to narrowing of the genetic base of the okra crop, one of the major factors attributed to breakdown of resistance/ tolerance to biotic stresses. YVMV and ELCV are the two major diseases, causing significant yield loss in okra. Hence, wide hybridization was attempted to transfer tolerance genes from wild species to the cultivated genepool to widen the genetic base. Material and methods: The screening of germplasm of wild Abelmoschus species at hotspots led to the identification of tolerant species (Abelmoschus pungens var. mizoramensis, A. enbeepeegeearensis, A. caillei, A. tetraphyllus and A. angulosus var. grandiflorus), which were further used in a wide-hybridization programme to generate interspecific hybrids with the cultivated okra. Presence of pre- and post-zygotic barriers to interspecific geneflow, differences in ploidy levels and genotype specific variations in chromosome numbers led to varying degrees of sterility in F1 plants of interspecific crosses. This was overcome by doubling the chromosome number of interspecific hybrids by applying Colchicine at the seedling stage. The 113 cross derivatives generated comprising amphidiploids in the F1 generation (30), F3 (14), one each in F2 and F4 generations, back cross generation in BC1F2 (03), BC1F3 (25), and BC2F3 (02), crosses between amphidiploids (27), multi-cross combinations (07) and inter-specific cross (between A. sagittifolius × A. moschatus subsp. moschatus) selfed derivatives at F8 generation (03) were characterized in the present study. Besides they were advanced through selfing and backcrossing. Results and Discussion: The amphidiploids were found to possess many desirable genes with a considerable magnitude of linkage drag. Majority of the wide cross derivatives had an intermediate fruit morphology and dominance of wild characters viz., hispid fruits, stem, leaves, tough fruit fibre, vigorous perennial growth habit and prolonged flowering and fruiting. The fruit morphology of three BC progenies exhibited a high morphological resemblance to the cultivated okra, confirming successful transfer of useful genes to the cultivated okra genepool. The detailed morphological characteristics of the various combinations of Abelmoschus amphidiploids and the genetic enhancement of the genepool achieved in this process is reported here.

16.
J Am Chem Soc ; 134(2): 1344-51, 2012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-22148234

RESUMO

Various 2-thienyllithium derivatives were investigated in the solid state by X-ray diffraction and in solution by 2D NMR experiments. The determined structures of [(Et(2)O)Li(C(4)H(3)S)](4) (1), [(THF)(2)Li(C(4)H(3)S)](2) (2), [(DME)Li(C(4)H(3)S)](2) (3), [(TMEDA)Li(C(4)H(3)S)](2) (4), and [(PMDETA)Li(C(4)H(3)S)] (5) (DME = 1,2-dimethoxyethane, TMEDA = N,N,N',N'-tetramethylethylene-1,2-diamine, and PMDETA = N,N,N',N",N"-pentamethyldiethylenetriamine) were solved in nondonating toluene and provide firm ground for diffusion-ordered NMR spectroscopy as well as heteronuclear Overhauser enhancement NMR spectroscopy. The distance relation of nuclear Overhauser effects with a factor of r(-6) is employed to gain further insight into the aggregation degree of 1-5 in solution. Comparison of the slope provided by the linear region of the buildup curves and of the ∑r(-6) calculated distances from the crystal structures offers a handle to judge the structure retention versus conversion in solution. The structures of 3-5 are maintained in toluene solution. The data of 2, however, indicate a partial dissociation or a rapid exchange between the vertices of a tetrameric core and free THF molecules. Auxiliary exchange spectroscopy investigations showed that the signals of the nitrogen donor base containing compounds 4 and 5 exchange with the signals of nonlithiated thiophene. This is explained by exchange of the deuterium by a hydrogen atom via lithiation of toluene molecules.

17.
J Org Chem ; 77(12): 5286-96, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22551444

RESUMO

An efficient synthesis of (-)-kainic acid, through a high-pressure-promoted Diels-Alder cycloaddition of a vinylogous malonate derived from 4-hydroxyproline, is described. The bicyclic adduct could be converted into the natural product with complete stereocontrol.


Assuntos
Ácido Caínico/síntese química , Ciclização , Hidroxiprolina/química , Ácido Caínico/química , Malonatos/química , Estrutura Molecular , Estereoisomerismo
18.
J Org Chem ; 77(7): 3233-45, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22372696

RESUMO

The linear syntheses of 4'-C-aminomethyl-2'-O-methyl uridine and cytidine nucleoside phosphoramidites were achieved using glucose as the starting material. The modified RNA building blocks were incorporated into small interfering RNAs (siRNAs) by employing solid phase RNA synthesis. Thermal melting studies showed that the modified siRNA duplexes exhibited slightly lower T(m) (∼1 °C/modification) compared to the unmodified duplex. Molecular dynamics simulations revealed that the 4'-C-aminomethyl-2'-O-methyl modified nucleotides adopt South-type conformation in a siRNA duplex, thereby altering the stacking and hydrogen-bonding interactions. These modified siRNAs were also evaluated for their gene silencing efficiency in HeLa cells using a luciferase-based reporter assay. The results indicate that the modifications are well tolerated in various positions of the passenger strand and at the 3' end of the guide strand but are less tolerated in the seed region of the guide strand. The modified siRNAs exhibited prolonged stability in human serum compared to unmodified siRNA. This work has implications for the use of 4'-C-aminomethyl-2'-O-methyl modified nucleotides to overcome some of the challenges associated with the therapeutic utilities of siRNAs.


Assuntos
Citidina/análogos & derivados , Nucleotídeos/síntese química , Nucleotídeos/genética , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Uridina/análogos & derivados , Sequência de Bases , Citidina/síntese química , Citidina/química , Inativação Gênica , Humanos , Ligação de Hidrogênio , Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Uridina/síntese química , Uridina/química
19.
Anaerobe ; 18(3): 366-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22710415

RESUMO

Catabacter hongkongensis is a recently recognised anaerobic gram positive bacillus. We report the isolation of a C. hongkongensis strain that does not utilise mannose, a novel phenotype, from the blood cultures of a patient with a perforated appendix. The isolate was identified by 16s rRNA gene sequencing. This case highlights the difficulties with phenotypic identification of rare anaerobic isolates. It also illustrates the association of C. hongkongensis bacteraemia with a gastrointestinal source and intestinal perforation.


Assuntos
Apendicite/diagnóstico por imagem , Bacteriemia/diagnóstico , Bactérias Gram-Positivas/isolamento & purificação , Infecções por Bactérias Gram-Positivas/diagnóstico , Apendicite/complicações , Apendicite/microbiologia , Bacteriemia/microbiologia , Meios de Cultura , Bactérias Gram-Positivas/metabolismo , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Manose/metabolismo , Pessoa de Meia-Idade , Fenótipo , Radiografia
20.
Dis Colon Rectum ; 54(3): 306-10, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21304301

RESUMO

BACKGROUND: With the introduction of biologic agents, medical and surgical management of ulcerative colitis has been associated with significant morbidity. A staged surgical approach is advocated to obviate the risks of infectious complication and consequent poor pouch function. OBJECTIVE: The aim of this study was to analyze the outcomes of our selective staged approaches in patients with ulcerative colitis who were undergoing laparoscopic pouch surgery. DESIGN: Consecutive patients with ulcerative colitis referred for laparoscopic surgical treatment between 2002 and 2008 were included in the study. Data were prospectively collected. Patients were divided into 2 groups: a 3-stage group, initial laparoscopic abdominal colectomy followed by pouch surgery with a diverting loop ileostomy, and a 2-stage group, laparoscopic pouch surgery with a diverting loop ileostomy at the initial operation. RESULTS: Of the 118 patients eligible for the study, 68 were in the 2-stage group and 50 were in the 3-stage group. Patients were more likely to have been receiving aggressive medical therapy in the 3-stage group than in the 2-stage group: 43% vs 16% (P = .01) receiving anti-tumor necrosis factor therapy and 96% vs 67% (P = .04) receiving systemic corticosteroids. Although overall complication rates were similar between groups (P = .4), infectious complications were higher in the 2-stage group (38.2% vs 21%, P < .05). CONCLUSIONS: In our practice, we have selectively applied a 3-stage laparoscopic surgical approach to restorative proctocolectomy in patients with ulcerative colitis who are receiving aggressive medical therapy in an attempt to minimize perioperative complications. This strategy appears efficacious, and short-term outcomes compare favorably with those following a 2-stage approach.


Assuntos
Colite Ulcerativa/cirurgia , Bolsas Cólicas , Ileostomia , Laparoscopia , Proctocolectomia Restauradora , Adolescente , Adulto , Estudos de Coortes , Colite Ulcerativa/complicações , Colite Ulcerativa/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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