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1.
J Stomatol Oral Maxillofac Surg ; 125(3S): 101865, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38570165

RESUMO

There are several treatment options to treat a class II dentofacial deformity with a pronounced chin. A total subapical osteotomy is one of these options. This type of osteotomy was refined to total subapical and ramus (TSAR) osteotomy. In this technical note, a detailed and schematic presentation of the TSAR osteotomy is presented step by step. The surgical approach to the TSAR osteotomy is divided into three parts. The first part consists of the horizontal osteotomy at the level of the ramus, the second part approaches the corticotomy to release and protect the mental nerve and the third part consists of connecting the horizontal ramus osteotomy and the local corticotomy around the mental nerve. In this third part, it is important that the inferior alveolar nerve (IAN) is actively sought and protected.


Assuntos
Má Oclusão Classe II de Angle , Humanos , Má Oclusão Classe II de Angle/cirurgia , Osteotomia Mandibular/métodos , Mandíbula/cirurgia , Nervo Mandibular/cirurgia , Queixo/cirurgia , Osteotomia/métodos , Osteotomia Sagital do Ramo Mandibular/métodos
2.
Front Ecol Evol ; 112023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37581102

RESUMO

Membrane-located NAD(P) transhydrogenase (NTH) catalyses reversible hydride ion transfer between NAD(H) and NADP(H), simultaneously translocating a proton across the membrane. The enzyme is structurally conserved across prokaryotes and eukaryotes. In heterotrophic bacteria NTH proteins reside in the cytoplasmic membrane, whereas in animals they localise in the mitochondrial inner membrane. Eukaryotic NTH proteins exists in two distinct configurations (isoforms) and have non-mitochondrial functions in unicellular eukaryotes like Plasmodium, the causative agent of malaria. In this study, we carried out a systematic analysis of nth genes across eukaryotic life to determine its prevalence and distribution of isoforms. The results reveal that NTH is found across all major lineages, but that some organisms, notably plants, lack nth genes altogether. Isoform distribution and phylogenetic analysis reveals different nth gene loss scenarios in apicomplexan lineages, which sheds new light on the evolution of the Piroplasmida and Eimeriidae.

3.
J Med Biogr ; : 9677720211053243, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34955051

RESUMO

The Scottish doctor Robert Erskine (1677-1718) became Chief Doctor of Russia and personal physician to Tsar Peter the Great. Extensive archival material documents his remarkable career. From schooling in the village of Alva and apprenticeship to an Edinburgh apothecary, he went on to study medicine in Paris and Utrecht and was admitted to the Royal Society in London. Recruited into the service of the Tsar, to whom he became a trusted friend and counsellor, Erskine played a central role in the modernisation of Russian medicine, pharmacy and natural science in the early 18th century. His untimely death at age 41 was marked with a state funeral in St Petersburg. Some historians in Russia assert that in their country, the development of medicine and the natural sciences took place without the transitional stages of iatrochemistry and iatrophysics which characterised the shift in scientific thinking throughout Europe in the early modern period. This study of archival records shows that Erskine held iatrophysical and iatrochemical views in common with his European contemporaries. His influence ensured that Russia was thoroughly involved in European developments in science and medicine in the 18th century.

4.
J Eukaryot Microbiol ; 68(1): e12825, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32875679

RESUMO

The stramenopiles are a large and diverse group of eukaryotes that possess various lifestyles required to thrive in a broad array of environments. The stramenopiles branch with the alveolates, rhizarians, and telonemids, forming the supergroup TSAR. Here, we present a new genus and species of aquatic nanoflagellated stramenopile: Mediocremonas mediterraneus, a free-swimming heterotrophic predator. M. mediterraneus cell bodies measure between 2.0-4.0 µm in length and 1.2-3.7 µm in width, possessing two flagella and an oval body morphology. The growth and grazing rate of M. mediterraneus in batch cultures ranges from 0.68 to 1.83 d-1 and 1.99 to 5.38 bacteria/h, respectively. M. mediterraneus was found to be 93.9% phylogenetically similar with Developayella elegans and 94.7% with Develorapax marinus, two members within the class Developea. The phylogenetic position of the Developea and the ability of M. mediterraneus to remain in culture make it a good candidate for further genomic studies that could help us to better understand phagotrophy in marine systems as well as the transition from heterotrophy to phototrophy within the stramenopiles.


Assuntos
Estramenópilas/classificação , Estramenópilas/citologia , Microscopia Eletrônica de Varredura , Filogenia , RNA de Algas/análise , RNA Ribossômico 16S/análise , Estramenópilas/genética , Estramenópilas/ultraestrutura
5.
J Med Biogr ; 29(4): 251-259, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32594892

RESUMO

Eugene Botkin was Nicholas II's court physician from 1908 until the abolition of the monarchy. He accompanied the royal family into exile and shared their fate at Ekaterinburg in 1918. The son of a prominent St. Petersburg physician, he trained at the Universities of St. Petersburg, Berlin, and Heidelberg. As court physician, he participated in the management of the Tsarevich Alexei's hemophilia, but most of his time was spent taking care of the Tsarina's multiple psychosomatic ailments. A deep sense of duty, rendered him unable to part from the royal family during the difficult months of exile and imprisonment. During this period there were several episodes of imminent threat to his life, where despite having the opportunity to leave, he voluntarily decided to stay with the Romanovs. In up to three occasions he said his goodbyes to his children, only to find out the next day that the threat had been contained. Ironically, the last time he spoke to them he did not think they would be separated for long. In this study, we will analyze his life, in particular the events of his last days, and will explore the reasoning behind his selfless actions.


Assuntos
Medicina , Médicos , Criança , Humanos , Masculino , Universidades
6.
Plant Physiol Biochem ; 154: 451-462, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32659648

RESUMO

The development of genetic transformation methods is critical for enabling the thorough characterization of an organism and is a key step in exploiting any species as a platform for synthetic biology and metabolic engineering approaches. In this work we describe the development of an Agrobacterium rhizogenes-mediated hairy root transformation protocol for the crop and medicinal legume fenugreek (Trigonella foenum-graecum). Fenugreek has a rich and diverse content in bioactive specialised metabolites, notably diosgenin, which is a common precursor for synthetic human hormone production. This makes fenugreek a prime target for identification and engineering of specific biosynthetic pathways for the production of triterpene and steroidal saponins, phenolics, and galactomanans. Through this transformation protocol, we identified a suitable promoter for robust transgene expression in fenugreek. Finally, we establish the proof of principle for the utility of the fenugreek system for metabolic engineering programs, by heterologous expression of known triterpene saponin biosynthesis regulators from the related legume Medicago truncatula in fenugreek hairy roots.


Assuntos
Engenharia Metabólica , Redes e Vias Metabólicas , Trigonella , Agrobacterium , Diosgenina , Humanos , Raízes de Plantas , Saponinas , Transformação Genética , Trigonella/genética , Trigonella/metabolismo
7.
Forensic Sci Med Pathol ; 16(3): 552-556, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32072440

RESUMO

The brutal execution of Tsar Nicholas II, his wife and five children at Yekaterinberg in July 1918 was followed by apparently inept attempts to conceal the bodies. Despite this, the skeletons remained undiscovered until 1979. Even after anthropological and DNA analyses, the absence of two of the children in the grave raised doubts as to the identity of the remains. The discovery of the skeletal fragments of a young woman aged between 18 to 25 years and a boy aged between 10 to 14 years in a shallow grave near the primary burial site in 2007 enabled full DNA investigations of the remains to be undertaken in association with analyses of living Romanov descendants. Autosomal short tandem repeat (STR) testing revealed the sex and familial relationships within the group, and mitochondrial DNA (mtDNA) testing of the two hypervariable regions (HVI and HVII) showed links between the Tsar and Tsarina and living maternal relatives. The same point heteroplasmy in both the Tsar and his brother, Georgii provided further supportive evidence. There appears little doubt that the skeletal remains in the two graves outside Yekaterinburg are those of Tsar Nicholas, his wife and their five children. The genetic analyses and the features of the fragmented remains are all very consistent with the tragic story of the last days of the Romanov family and with the subsequent desecration and destruction of their bodies.


Assuntos
Restos Mortais , Homicídio , Adolescente , Adulto , Criança , Impressões Digitais de DNA , DNA Mitocondrial/genética , Feminino , Heteroplasmia , História do Século XIX , História do Século XX , Humanos , Masculino , Repetições de Microssatélites , Linhagem , Federação Russa , Adulto Jovem
8.
Cells ; 8(5)2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075917

RESUMO

Mitochondria are unique organelles carrying their own genetic material, independent from that in the nucleus. This review will discuss the nature of mitochondrial DNA (mtDNA) and its levels in the cell, which are the key elements to consider when trying to achieve molecular identification in ancient and degraded samples. mtDNA sequence analysis has been appropriately validated and is a consistent molecular target for the examination of biological evidence encountered in forensic cases-and profiling, in certain conditions-especially for burnt bodies and degraded samples of all types. Exceptional cases and samples will be discussed in this review, such as mtDNA from leather in Beethoven's grand piano, mtDNA in mummies, and solving famous historical criminal cases. In addition, this review will be discussing the use of ancient mtDNA to understand past human diet, to trace historical civilizations and ancient trade routes, and to uncover geographical domestication origins and lineage relationships. In each topic, we will present the power of mtDNA and how, in many cases, no nuclear DNA was left, leaving mitochondrial DNA analysis as a powerful alternative. Exploring this powerful tool further will be extremely useful to modern science and researchers, due to its capabilities in providing us with previously unattainable knowledge.


Assuntos
Civilização , DNA Antigo/análise , DNA Mitocondrial/genética , Domesticação , Homicídio/história , Música , História do Século XVIII , Humanos
9.
Mol Biol Evol ; 36(4): 757-765, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668767

RESUMO

The resolution of the broad-scale tree of eukaryotes is constantly improving, but the evolutionary origin of several major groups remains unknown. Resolving the phylogenetic position of these "orphan" groups is important, especially those that originated early in evolution, because they represent missing evolutionary links between established groups. Telonemia is one such orphan taxon for which little is known. The group is composed of molecularly diverse biflagellated protists, often prevalent although not abundant in aquatic environments. Telonemia has been hypothesized to represent a deeply diverging eukaryotic phylum but no consensus exists as to where it is placed in the tree. Here, we established cultures and report the phylogenomic analyses of three new transcriptome data sets for divergent telonemid lineages. All our phylogenetic reconstructions, based on 248 genes and using site-heterogeneous mixture models, robustly resolve the evolutionary origin of Telonemia as sister to the Sar supergroup. This grouping remains well supported when as few as 60% of the genes are randomly subsampled, thus is not sensitive to the sets of genes used but requires a minimal alignment length to recover enough phylogenetic signal. Telonemia occupies a crucial position in the tree to examine the origin of Sar, one of the most lineage-rich eukaryote supergroups. We propose the moniker "TSAR" to accommodate this new mega-assemblage in the phylogeny of eukaryotes.


Assuntos
Eucariotos/genética , Filogenia , Eucariotos/metabolismo , Transcriptoma
10.
J Microbiol Immunol Infect ; 49(1): 52-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24662016

RESUMO

BACKGROUND: The prevalence and clinical impact on mortality of carbapenem-resistant Pseudomonas aeruginosa (CRPA) is unclear in Taiwan. We aim to clarify these clinical issues by using data from the Taiwan Surveillance of Antimicrobial Resistance (TSAR) program. METHODS: Patients from five hospitals with their P. aeruginosa isolates collected by TSAR II-VII (2000-2010) program were considered as the potential study population. All patients with CRPA were enrolled as case patients. Patients with carbapenem-susceptible P. aeruginosa were randomly selected in a 1:1 ratio to case patients as control patients. CRPA isolates were tested for the presence of carbapenemase-producing genes. The clinical data were collected to identify risk factors for CRPA carriage and mortality of P. aeruginosa infection. RESULTS: The overall prevalence of CRPA was 10.2% (349/3408), which increased significantly by the TSAR period (p = 0.007). Among the 164 enrolled patients, the risk factor for carrying CRPA was previous fluoroquinolone exposure (p = 0.004). The risk factors for mortality among 80 patients with infection by P. aeruginosa included: intensive care unit (ICU) setting, receipt of antifungal therapy, and presence of invasive devices (p = 0.001, 0.010, and 0.017; respectively). Carbapenem resistance did not play a role. Among the 82 CRPA isolates enrolled in this study, 15 isolates were found to carry carbapenemase-producing genes. CONCLUSION: In Taiwan, the prevalence of CRPA and carriage of carbapenemase-producing genes was high. However, carbapenem resistance did not play a role in the mortality of patients with P. aeruginosa infections.


Assuntos
Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Resistência beta-Lactâmica , Adulto , Idoso , Idoso de 80 Anos ou mais , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/mortalidade , Pseudomonas aeruginosa/isolamento & purificação , Fatores de Risco , Análise de Sobrevida , Taiwan/epidemiologia , Resultado do Tratamento
11.
Biochim Biophys Acta ; 1834(12): 2663-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24076009

RESUMO

NADPH-dependent glyoxylate reductases from Arabidopsis thaliana (AtGLYR) convert both glyoxylate and succinic semialdehyde into their corresponding hydroxyacid equivalents. The primary sequence of cytosolic AtGLYR1 reveals several sequence elements that are consistent with the ß-HAD (ß-hydroxyacid dehydrogenase) protein family, whose members include 3-hydroxyisobutyrate dehydrogenase, tartronate semialdehyde reductase and 6-phosphogluconate dehydrogenase. Here, site-directed mutagenesis was utilized to identify catalytically important amino acid residues for glyoxylate reduction in AtGLYR1. Kinetic studies and binding assays established that Lys170 is essential for catalysis, Phe231, Asp239, Ser121 and Thr95 are more important in substrate binding than in catalysis, and Asn174 is more important in catalysis. The low activity of the mutant enzymes precluded kinetic studies with succinic semialdehyde. The crystal structure of AtGLYR1 in the absence of substrate was solved to 2.1Å by molecular replacement using a previously unrecognized member of the ß-HAD family, cytokine-like nuclear factor, thereby enabling the 3-D structure of the protein to be modeled with substrate and co-factor. Structural alignment of AtGLYR1 with ß-HAD family members provided support for the essentiality of Lys170, Phe173, Asp239, Ser121, Asn174 and Thr95 in the active site and preliminary support for an acid/base catalytic mechanism involving Lys170 as the general acid and a conserved active-site water molecule. This information established that AtGLYR1 is a member of the ß-HAD protein family. Sequence and activity comparisons indicated that AtGLYR1 and the plastidial AtGLYR2 possess structural features that are absent in Arabidopsis hydroxypyruvate reductases and probably account for their stronger preference for glyoxylate over hydroxypyruvate.


Assuntos
Oxirredutases do Álcool/química , Aminoácidos/química , Proteínas de Arabidopsis/química , Arabidopsis/enzimologia , Proteínas de Cloroplastos/química , Glioxilatos/química , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Substituição de Aminoácidos , Aminoácidos/genética , Aminoácidos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Domínio Catalítico , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , Cristalografia por Raios X , Glioxilatos/metabolismo , Mutação de Sentido Incorreto , Oxirredução , Relação Estrutura-Atividade , Especificidade por Substrato
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