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1.
Curr Zool ; 68(4): 423-432, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36090142

RESUMO

Dogs were the first animal to become domesticated by humans, and they represent a classic model system for unraveling the processes of domestication. We compare Australian dingo eye contact and socialization with Basenji and German Shepherd dog (GSD) breeds. Australian dingoes arrived in Australia 5,000-8,000 BP, and there is debate whether they were domesticated before their arrival. The Basenji represents a primitive breed that diverged from the remaining breeds early in the domestication process, while GSDs are a breed dog selected from existing domestic dogs in the late 1800s. We conducted a 4-phase study with unfamiliar and familiar investigators either sitting passively or actively calling each canid. We found 75% of dingoes made eye contact in each phase. In contrast, 86% of Basenjis and 96% of GSDs made eye contact. Dingoes also exhibited shorter eye-gaze duration than breed dogs and did not respond to their name being called actively. Sociability, quantified as a canid coming within 1 m of the experimenter, was lowest for dingoes and highest for GSDs. For sociability duration, dingoes spent less time within 1 m of the experimenter than either breed dog. When compared with previous studies, these data show that the dingo is behaviorally intermediate between wild wolves and Basenji dogs and suggest that it was not domesticated before it arrived in Australia. However, it remains possible that the accumulation of mutations since colonization has obscured historical behaviors, and dingoes now exist in a feralized retamed cycle. Additional morphological and genetic data are required to resolve this conundrum.

2.
Front Genet ; 13: 982589, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092913

RESUMO

Genomic regions governing days to heading (DH), grain filling duration (GFD), grain number per spike (GNPS), grain weight per spike (GWPS), plant height (PH), and grain yield (GY) were investigated in a set of 280 diverse bread wheat genotypes. The genome-wide association studies (GWAS) panel was genotyped using a 35K Axiom Array and phenotyped in five environments. The GWAS analysis showed a total of 27 Bonferroni-corrected marker-trait associations (MTAs) on 15 chromosomes representing all three wheat subgenomes. The GFD showed the highest MTAs (8), followed by GWPS (7), GY (4), GNPS (3), PH (3), and DH (2). Furthermore, 20 MTAs were identified with more than 10% phenotypic variation. A total of five stable MTAs (AX-95024590, AX-94425015, AX-95210025 AX-94539354, and AX-94978133) were identified in more than one environment and associated with the expression of DH, GFD, GNPS, and GY. Similarly, two novel pleiotropic genomic regions with associated MTAs i.e. AX-94978133 (4D) and AX-94539354 (6A) harboring co-localized QTLs governing two or more traits were also identified. In silico analysis revealed that the SNPs were located on important putative candidate genes such as F-box-like domain superfamily, Lateral organ boundaries, LOB, Thioredoxin-like superfamily Glutathione S-transferase, RNA-binding domain superfamily, UDP-glycosyltransferase family, Serine/threonine-protein kinase, Expansin, Patatin, Exocyst complex component Exo70, DUF1618 domain, Protein kinase domain involved in the regulation of grain size, grain number, growth and development, grain filling duration, and abiotic stress tolerance. The identified novel MTAs will be validated to estimate their effects in different genetic backgrounds for subsequent use in marker-assisted selection (MAS).

3.
Sci Adv ; 8(16): eabm5944, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35452284

RESUMO

Dogs are uniquely associated with human dispersal and bring transformational insight into the domestication process. Dingoes represent an intriguing case within canine evolution being geographically isolated for thousands of years. Here, we present a high-quality de novo assembly of a pure dingo (CanFam_DDS). We identified large chromosomal differences relative to the current dog reference (CanFam3.1) and confirmed no expanded pancreatic amylase gene as found in breed dogs. Phylogenetic analyses using variant pairwise matrices show that the dingo is distinct from five breed dogs with 100% bootstrap support when using Greenland wolf as the outgroup. Functionally, we observe differences in methylation patterns between the dingo and German shepherd dog genomes and differences in serum biochemistry and microbiome makeup. Our results suggest that distinct demographic and environmental conditions have shaped the dingo genome. In contrast, artificial human selection has likely shaped the genomes of domestic breed dogs after divergence from the dingo.


Assuntos
Canidae , Lobos , Animais , Austrália , Cruzamento , Canidae/genética , Cães , Filogenia , Lobos/genética
4.
Org Lett ; 23(12): 4909-4914, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34100619

RESUMO

We describe the first atropselective Suzuki-Miyaura cross-coupling of ß-keto enol triflates to access axially chiral (Z)-diarylmethylidene indanones (DAIs). The chemical, physical, and biological properties of DAIs are unknown, despite their being structurally similar to arylidene indanones, primarily due to the lack of racemic or chiral methods. Through this work, we demonstrate a general and efficient protocol for the racemic as well as the atropselective synthesis of (Z)-DAIs. An unusual intramolecular Morita-Baylis-Hillman reaction is utilized for the Z-selective synthesis of ß-keto enol triflates.

5.
Cells Dev ; 166: 203682, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33994355

RESUMO

Homeotic genes and their genomic organization show remarkable conservation across bilaterians. Consequently, the regulatory mechanisms, which control hox gene expression, are also highly conserved. The crucial presence of conserved GA rich motifs between Hox genes has been previously observed but what factor binds to these is still unknown. Previously we have reported that the vertebrate homologue of Drosophila Trl-GAF preferentially binds to GA rich regions in Evx2-hoxd13 intergenic region of vertebrate HoxD cluster. In this study, we show that the vertebrate-GAF (v-GAF) binds at known cis-regulatory elements in the HoxD complex of zebrafish and mouse. We further used morpholino based knockdown and CRISPR-cas9 knockout technique to deplete the v-GAF in zebrafish. We checked expression of the HoxD genes and found gain of the HoxD4 gene in GAF knockout embryos. Further, we partially rescued the morphological phenotypes in GAF depleted embryos by providing GAF mRNA. Our results show that GAF binds at intergenic regions of the HoxD complex and is important for maintaining the spatial domains of HoxD4 expression during embryonic development.


Assuntos
Desenvolvimento Embrionário , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Padronização Corporal/genética , Desenvolvimento Embrionário/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Vesiculares de Transporte de Aminoácidos Inibidores/genética , Proteínas de Peixe-Zebra/genética
6.
Chem Rec ; 21(12): 3470-3482, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33971073

RESUMO

The development of new synthetic protocols to access diverse molecular scaffolds from readily available starting compounds is of significance in both academia and industry. Towards this, the catalysis by transition metals has been employed as a powerful tool to access molecules with broad structural and functional diversity. An overview of the recent literature manifested the tremendous potential of transition metal-catalyzed processes in advancing organic synthesis in a new direction. This account compiles new conceptual advancements in the palladium-catalyzed Alder-ene type cycloisomerization reactions, C-H functionalizations, and one-pot multicatalytic processes, which have become essential tools to access new classes of molecules.


Assuntos
Paládio , Catálise , Técnicas de Química Sintética , Estereoisomerismo
7.
Trop Med Infect Dis ; 6(2)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33923973

RESUMO

In the era of growing antimicrobial resistance, there is a concern about the effectiveness of first-line antibiotics such as ampicillin in children hospitalized with community-acquired pneumonia. In this study, we describe antibiotic use and treatment outcomes among under-five children with community-acquired pneumonia admitted to a tertiary care public hospital in Nepal from 2017 to 2019. In this cross-sectional study involving secondary analysis of hospital data, there were 659 patients and 30% of them had a history of prehospital antibiotic use. Irrespective of prehospital antibiotic use, ampicillin monotherapy (70%) was the most common first-line treatment provided during hospitalization followed by ceftriaxone monotherapy (12%). The remaining children (18%) were treated with various other antibiotics alone or in combination as first-line treatment. Broad-spectrum antibiotics such as linezolid, vancomycin, and meropenem were used in less than 1% of patients. Overall, 66 (10%) children were required to switch to second-line treatment and only 7 (1%) children were required to switch to third-line treatment. Almost all (99%) children recovered without any sequelae. This study highlights the effectiveness of ampicillin monotherapy in the treatment of community-acquired pneumonia in hospitalized children in a non-intensive care unit setting.

8.
Sci Rep ; 11(1): 5245, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664285

RESUMO

Dingoes occupy a wide range of the Australian mainland and play a crucial role as an apex predator with a generalist omnivorous feeding behaviour. Dingoes are ecologically, phenotypically and behaviourally distinct from modern breed dogs and have not undergone artificial selection since their arrival in Australia. In contrast, humans have selected breed dogs for novel and desirable traits. First, we examine whether the distinct evolutionary histories of dingoes and domestic dogs has lead to differences in plasma metabolomes. We study metabolite composition differences between dingoes (n = 15) and two domestic dog breeds (Basenji n = 9 and German Shepherd Dog (GSD) n = 10). Liquid chromatography mass spectrometry, type II and type III ANOVA with post-hoc tests and adjustments for multiple comparisons were used for data evaluation. After accounting for within group variation, 62 significant metabolite differences were detected between dingoes and domestic dogs, with the majority of differences in protein (n = 14) and lipid metabolites (n = 12), mostly lower in dingoes. Most differences were observed between dingoes and domestic dogs and fewest between the domestic dog breeds. Next, we collect a second set of data to investigate variation between pure dingoes (n = 10) and dingo-dog hybrids (n = 10) as hybridisation is common in regional Australia. We detected no significant metabolite differences between dingoes and dingo-dog hybrids after Bonferroni correction. However, power analysis showed that increasing the sample size to 15 could result in differences in uridine 5'-diphosphogalactose (UDPgal) levels related to galactose metabolism. We suggest this may be linked to an increase in Amylase 2B copy number in hybrids. Our study illustrates that the dingo metabolome is significantly different from domestic dog breeds and hybridisation is likely to influence carbohydrate metabolism.


Assuntos
Animais Selvagens/genética , Canidae/genética , Metabolômica , Filogenia , Animais , Animais Domésticos/genética , Animais Domésticos/metabolismo , Animais Selvagens/metabolismo , Austrália , Cruzamento , Canidae/metabolismo , Cães , Humanos , Metabolismo dos Lipídeos/genética , Lipídeos , Lobos/genética , Lobos/metabolismo
9.
Mol Ecol ; 30(2): 481-498, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33217095

RESUMO

Local adaptation can occur at small spatial scales relative to the dispersal capacity of species. Alpine ecosystems have sharp environmental clines that offer an opportunity to investigate the effects of fine-scale shifts in species' niche breadth on adaptive genetic processes. Here we examine two grasshopper species endemic to the Australian Alps (Kosciuscola spp.) that differ in elevational niche breadth: one broader, K. usitatus (1400-2200 m), and one narrower, K. tristis (1600-2000 m). We examine signatures of selection with respect to environmental and morphological variables in two mountain regions using FST outlier tests and environmental association analyses (EAAs) applied to single nucleotide polymorphism (SNP) data (K. usitatus: 9017 SNPs, n = 130; K. tristis: 7363 SNPs, n = 135). Stronger genetic structure was found in the more narrowly distributed K. tristis, which showed almost twice the number of SNPs under putative selection (10.8%) compared with K. usitatus (5.3%). When examining SNPs in common across species (n = 3058), 260 SNPs (8.5%) were outliers shared across species, and these were mostly associated with elevation, a proxy for temperature, suggesting parallel adaptive processes in response to climatic drivers. Additive polygenic scores (an estimate of the cumulative signal of selection across all candidate loci) were nonlinearly and positively correlated with elevation in both species. However, a steeper correlation in K. tristis indicated a stronger signal of spatially varying selection towards higher elevations. Our study illustrates that the niche breadth of co-occurring and related species distributed along the same environmental cline is associated with differences in patterns of microgeographical adaptation.


Assuntos
Genética Populacional , Gafanhotos , Adaptação Fisiológica/genética , Animais , Austrália , Ecossistema , Gafanhotos/genética , Polimorfismo de Nucleotídeo Único/genética
10.
Chem Commun (Camb) ; 57(1): 77-80, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33245742

RESUMO

A conceptually novel intramolecular allylic alkylation strategy is developed for the synthesis of carbazoles and dibenzothiophenes. In an unusual event, palladium catalyses the formation of π-allylpalladium complexes of the respective (2-methylindol-3-yl)allyl acetates and subsequently facilitates the benzannulation process.

11.
Chem Asian J ; 15(18): 2764-2774, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32667724

RESUMO

An overview of the recent literature on palladium-catalyzed intramolecular Alder-ene (IMAE) reaction of a variety of 1,n-unsaturated systems is presented. The reaction which was first reported by Trost and Lautens provided an efficient alternative to the thermal or Lewis acid catalyzed cycloisomerizations involving ene-type reaction. The IMAE cyclization of enynes and dienes has emerged as an important area and found significant applications in building up of complex molecular architectures and in the synthesis of several bioactive natural products. Since highly impactful reviews on this subject have covered the literature till 2015, this article focuses on summarizing the works subsequent to 2015.

12.
Planta Med ; 86(16): 1161-1175, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32663897

RESUMO

According to the World Health Organization, neurological and neurodegenerative diseases are highly debilitating and pose the greatest threats to public health. Diseases of the nervous system are caused by a particular pathological process that negatively affects the central and peripheral nervous systems. These diseases also lead to the loss of neuronal cell function, which causes alterations in the nervous system structure, resulting in the degeneration or death of nerve cells throughout the body. This causes problems with movement (ataxia) and mental dysfunction (dementia), both of which are commonly observed symptoms in Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. Medicinal mushrooms are higher fungi with nutraceutical properties and are low in calories and fat. They are also a rich source of nutrients and bioactive compounds such as carbohydrates, proteins, fibers, and vitamins that have been used in the treatment of many ailments. Medicinal mushrooms such as Pleurotus giganteus, Ganoderma lucidium, and Hericium erinaceus are commonly produced worldwide for use as health supplements and medicine. Medicinal mushrooms and their extracts have a large number of bioactive compounds, such as polysaccharide ß-glucan, or polysaccharide-protein complexes, like lectins, lactones, terpenoids, alkaloids, antibiotics, and metal-chelating agents. This review will focus on the role of the medicinal properties of different medicinal mushrooms that contain bioactive compounds with a protective effect against neuronal dysfunction. This information will facilitate the development of drugs against neurodegenerative diseases.


Assuntos
Agaricales , Ganoderma , Doenças Neurodegenerativas , Pleurotus , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Polissacarídeos
13.
Mol Ecol ; 28(14): 3395-3412, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31177610

RESUMO

Widespread species that exhibit both high gene flow and the capacity to occupy heterogeneous environments make excellent models for examining local selection processes along environmental gradients. Here we evaluate the influence of temperature and landscape variables on genetic connectivity and signatures of local adaptation in Phaulacridium vittatum, a widespread agricultural pest grasshopper, endemic to Australia. With sampling across a 900-km latitudinal gradient, we genotyped 185 P. vittatum from 19 sites at 11,408 single nucleotide polymorphisms (SNPs) using ddRAD sequencing. Despite high gene flow across sites (pairwise FST  = 0.0003-0.08), landscape genetic resistance modelling identified a positive nonlinear effect of mean annual temperature on genetic connectivity. Urban areas and water bodies had a greater influence on genetic distance among sites than pasture, agricultural areas and forest. Together, FST outlier tests and environmental association analysis (EAA) detected 242 unique SNPs under putative selection, with the highest numbers associated with latitude, mean annual temperature and body size. A combination of landscape genetic connectivity analysis together with EAA identified mean annual temperature as a key driver of both neutral gene flow and environmental selection processes. Gene annotation of putatively adaptive SNPs matched with gene functions for olfaction, metabolic detoxification and ultraviolet light shielding. Our results imply that this widespread agricultural pest has the potential to spread and adapt under shifting temperature regimes and land cover change.


Assuntos
Adaptação Fisiológica/genética , Gafanhotos/genética , Animais , Teorema de Bayes , Meio Ambiente , Frequência do Gene/genética , Geografia , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único/genética , Temperatura
14.
Org Lett ; 21(9): 2983-2987, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-30985137

RESUMO

An efficient palladium-catalyzed intramolecular Trost-Oppolzer type Alder-ene strategy was developed for the synthesis of carbazoles and cyclopenta[ b]indoles from easily accessible(3-allyl-1 H-indol-2-yl)methyl acetates. This strategy was extended for the synthesis of naphthalenes and dibenzobenzofurans as well. In addition, a short synthesis of antibacterial and antifungal natural product glycozoline and its analogues was also achieved.

15.
J Insect Sci ; 18(6)2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30508202

RESUMO

Invertebrate pests often show high morphological variation and wide environmental tolerances. Knowledge of how phenotypic variation is associated with environmental heterogeneity can elucidate the processes underpinning these patterns. Here we examine morphological variation and relative abundance along environmental gradients in a widespread agricultural pest, native to Australia, the wingless grasshopper Phaulacridium vittatum (Sjöstedt). We test for correlations between body size, wing presence, and stripe polymorphism with environmental variables. Using multiple regression and mixed-effects modeling, body size and stripe polymorphism were positively associated with solar radiation, and wing presence was positively associated with foliage projective cover (FPC). There were no associations between body size or morphological traits with relative abundance. However, relative abundance was positively associated with latitude, soil moisture, and wind speed, but was negatively associated with FPC. Therefore, sites with low relative abundance and high forest cover were more likely to contain winged individuals. Overall, our results suggest that environmental and climatic conditions strongly influence the relative abundance and the distribution of morphotypes in P. vittatum, which is likely to affect dispersal and fitness in different landscapes. This knowledge is useful for informing how environmental change might influence the future spread and impact of this agricultural pest.


Assuntos
Meio Ambiente , Gafanhotos/anatomia & histologia , Agricultura , Animais , Austrália , Fenótipo , Densidade Demográfica
16.
Indian J Anaesth ; 62(1): 47-52, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29416150

RESUMO

BACKGROUND AND AIMS: Effect of serum 25-hydroxy vitamin D (25[OH] D) levels on the recovery of critically ill mechanically ventilated patients is unclear. Hence, this study assessed 25(OH)D levels of critically ill patients on mechanical ventilation at the time of admission to the Intensive Care Unit (ICU) and its relationship with clinical outcome. METHODS: In this prospective observational pilot study, forty adult patients receiving mechanical ventilation in the ICU were included. Serum 25(OH)D was assessed within 24 h of admission. Primary outcome was 30-day mortality and secondary outcomes were days on mechanical ventilation, ICU-length of stay (ICU-LOS), days to reach spontaneous breathing trial (SBT), requirement of advanced care modality and complications. RESULTS: Seventy-five percent patients had low serum 25(OH)D (65% deficient and 10% insufficient). Between patients with low and normal vitamin D, there was no significant difference in 30-day mortality (10% vs. 16.7%; P = 0.81), days on mechanical ventilation (16.2 ± 8.9 vs. 19.9 ± 8.4; P = 0.23), ICU-length of stay (18.7 ± 8.5 vs. 23.3 ± 11.4; P = 0.28), days to reach SBT (11.5 (0-20) vs. 21 (8-30); P = 0.78), complications developed during ICU stay (P = 0.60) and need for advanced care modalities (P = 0.72). CONCLUSION: Low Vitamin D level at admission did not affect 30-day mortality of critically ill patients on mechanical ventilation.

17.
J Org Chem ; 82(13): 6729-6737, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28613866

RESUMO

Diversity oriented one-pot synthesis of cyclohepta[b]indoles, indolotropones, and tetrahydrocarbazoles (THCs) have been reported. Readily accessible 3-(2-aminophenyl)-5-hexenyn-3-ols under a one-pot trimetallic orthogonal catalysis furnish tetrahydrocyclohepta[b]indoles, and a one-pot quadruple reaction sequence of the enynols generates dihydrocyclohepta[b]indoles and indolotropones. During this study, formation of THCs was realized to be a reason for the yield loss in certain cases, this observation led to the development of a one-pot bimetallic approach for the synthesis of 1,3-disubstituted THCs.

19.
BMC Genet ; 17: 37, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26860950

RESUMO

BACKGROUND: Non-invasive sampling has opened avenues for the genetic study of elusive species, which has contributed significantly to their conservation. Where field based identity of non-invasive sample is ambiguous (e.g. carnivore scats), it is essential to establish identity of the species through molecular approaches. A cost effective procedure to ascertain species identity is to use species specific primers (SSP) for PCR amplification and subsequent resolution through agarose gel electrophoresis. However, SSPs if ill designed can often cross amplify non-target sympatric species. Herein we report the problem of cross amplification with currently published SSPs, which have been used in several recent scientific articles on tigers (Panthera tigris) and leopards (Panthera pardus) in India. Since these papers form pioneering research on which future work will be based, an early rectification is required so as to not propagate this error further. RESULTS: We conclusively show cross amplification of three of the four SSPs, in sympatric non-target species like tiger SSP amplifying leopard and striped hyena (Hyaena hyaena), and leopard SSP amplifying tiger, lion (Panthera leo persica) and clouded leopard (Neofelis nebulosa), with the same product size. We develop and test a non-cross-amplifying leopard specific primer pair within the mitochondrial cytochrome b region. We also standardize a duplex PCR method to screen tiger and leopard samples simultaneously in one PCR reaction to reduce cost and time. CONCLUSIONS: These findings suggest the importance of an often overlooked preliminary protocol of conclusive identification of species from non-invasive samples. The cross amplification of published primers in conspecifics suggests the need to revisit inferences drawn by earlier work.


Assuntos
Primers do DNA/genética , Panthera/genética , Tigres/genética , Animais , Citocromos b/genética , Citocromos b/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Índia , Panthera/classificação , Reação em Cadeia da Polimerase , Especificidade da Espécie , Tigres/classificação
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