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141.
Veronica Murta Priscila Schilrreff Gerardo Rosciszewski Maria Jose Morilla Alberto Javier Ramos 《Journal of neurochemistry》2018,144(6):748-760
142.
Priscila Dallé da Rosa Claudete Locatelli Karla Scheid Diane Marinho Lúcia Kliemann Alexandre Fuentefria Luciano Zubaran Goldani 《Mycopathologia》2018,183(3):565-571
Lasiodiplodia theobromae is a rare ocular pathogen. We report a patient with fungal keratitis caused by L. theobromae. The patient was a 75-year-old male, a farmer with diabetes type II, and no previous history of ocular trauma. Histopathology analysis revealed the presence fungi invading Descemet’s membrane of the cornea. The fungus was characterized by septate, highly bulged fungal filaments involving full corneal thickness in the corresponding histopathology specimens. A dematiaceous mold was isolated and initally identified as L. theobromae by microscopic and macroscopic morphology, and further confirmed by PCR-based determination of internal transcribed spacer (ITS) regions of ribosomal DNA. Antifungal susceptibility tests showed sensitivity to amphotericin B (AMB) and voriconazole ( VRC), and resistance to other azoles, including itraconazole (ITC) and fluconazole (FLC). Corneal transplant was performed. Despite in vitro itraconazole resistance, the patient was successfully treated with oral itraconazole, topical voriconazole and natamycin, combined with ocular injections of amphotericin B and voriconazole. 相似文献
143.
Gabriele Maria Sgarlata Jordi Salmona Isa Aleixo-Pais Ando Rakotonanahary Ana Priscila Sousa Célia Kun-Rodrigues Tantely Ralantoharijaona Fabien Jan Radavison Zaranaina Emmanuel Rasolondraibe John Rigobert Zaonarivelo Nicole Volasoa Andriaholinirina Lounès Chikhi 《International journal of primatology》2018,39(1):65-89
Phylogeographic barriers, together with habitat loss and fragmentation, contribute to the evolution of a species’ genetic diversity by limiting gene flow and increasing genetic differentiation among populations. Changes in connectivity can thus affect the genetic diversity of populations, which may influence the evolutionary potential of species and the survival of populations in the long term. We studied the genetic diversity of the little known Northern rufous mouse lemur (Microcebus tavaratra), endemic to Northern Madagascar. We focused on the population of M. tavaratra in the Loky–Manambato region, Northern Madagascar, a region delimited by two permanent rivers and characterized by a mosaic of fragmented forests. We genotyped 148 individuals at three mitochondrial loci (D-loop, cytb, and cox2) in all the major forests of the study region. Our analyses suggest that M. tavaratra holds average genetic diversity when compared to other mouse lemur species, and we identified two to four genetic clusters in the study region, a pattern similar to that observed in another lemur endemic to the region (Propithecus tattersalli). The main cluster involved samples from the two mountain forests in the study region, which were connected until recently. However, the river crossing the study region does not appear to be a strict barrier to gene flow in M. tavaratra. Finally, the inferred demographic history of M. tavaratra suggests no detectable departure from stationarity over the last millennia. Comparisons with codistributed species (P. tattersalli and two endemic rodents, Eliurus spp.) suggest both differences and similarities in the genetic clusters identified (i.e., barriers to species dispersal) and in the inferred demographic history. These comparisons suggest that studies of codistributed species are important to understand the effects of landscape features on species and to reconstruct the history of habitat changes in a region. 相似文献
144.
145.
Alex Henrique Tiene Ortiz Vanesca Priscila Camargo Rocha Leonel Domingos Moiana Maria Celeste Gonçalves-Vidigal Marta Zulema Galván Pedro Soares Vidigal Filho 《Plant Molecular Biology Reporter》2016,34(6):1153-1166
F is (0.170) and F it (0.259) values indicated a number of heterozygotes present in the population under study lower than that necessary to reach the Hardy-Weinberg equilibrium. The genetic variability found among the traditional sweet cassava cultivars assessed was considered wide, and the groups that were most distant were mostly cultivars from Toledo and Maringá. 相似文献
146.
Michele R. Spier Francieli B. Siepmann Larissa Staack Priscila Z. Souza Vikas Kumar Adriane B. P. Medeiros 《Preparative biochemistry & biotechnology》2016,46(7):725-733
The development of stable enzymes is a key issue in both the food and feed industries. Consequently, the aim of the current study is to evaluate the impact of various additives (sodium chloride, sodium citrate, mannitol, methylparaben, polyethylene glycol 3350, ethylenediaminetetraacetic acid disodium salt, and a serine protease inhibitor) on the stability of a mushroom phytase produced by solid-state cultivation and recovery. Also observed was the effect of the additives on microbial growth inhibition by monitoring both the change in optical density over 30 days of storage and proteolytic activity. Initially, eight experimental formulations were prepared along with a control. After screening, a 32 factorial design was applied to define suitable concentrations of the selected additives. Among the eight formulations tested, the formulation containing NaCl, PEG 3350, and methylparaben retained all of the initial phytase activity after 50 days of storage, with no detected interference from protease activity. Sodium citrate, a metal chelation agent, presented the unusual effect of reducing protease activity in the formulations. Although all formulations presented better phytase stability when compared to the control, NaCl and PEG were both able to prolong the stability of the enzyme activity and also to inhibit microbial growth during storage, making them favorable for application as food and feed additives. 相似文献
147.
The Essential Oil Compositions of Ocimum basilicum from Three Different Regions: Nepal,Tajikistan, and Yemen 下载免费PDF全文
Farukh S. Sharopov Prabodh Satyal Nasser A. Awadh Ali Suraj Pokharel Hanjing Zhang Michael Wink Muhammadsho A. Kukaniev William N. Setzer 《化学与生物多样性》2016,13(2):241-248
The aerial parts of Ocimum basilicum L. were collected from four different geographical locations, Sindhuli and Biratnagar (Nepal), Chormaghzak village (Tajikistan), and Sana'a (Yemen). The essential oils were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. A cluster analysis of 179 essential oil compositions revealed six major chemotypes: Linalool, eugenol, estragole, methyl eugenol, 1,8‐cineole, and geraniol. All four of the basil oils in this study were of the linalool‐rich variety. Some of the basil oils were screened for bioactivity including antimicrobial, cytotoxicity in human cancer cells, brine shrimp lethality, nematicidal, larvicidal, insecticidal, and antioxidant. The basil oils in this study were not notably antibacterial, cytotoxic, antioxidant, nor nematicidal, but were active in the brine shrimp lethality test, and did show larvicidal and insecticidal activities. 相似文献
148.
Chemodiversity Associated with Cytotoxicity and Antimicrobial Activity of Piper aduncum var. ossanum 下载免费PDF全文
Yamilet Gutiérrez Rodny Montes Ramón Scull Arturo Sánchez Paul Cos Lianet Monzote William N. Setzer 《化学与生物多样性》2016,13(12):1715-1719
Chemical analysis, antimicrobial activity and cytotoxic effects of essential oils (EOs) from leaves of Piper aduncum var. ossanum from two localities Bauta (EO‐B) and Ceiba (EO‐C), Artemisa Province, Cuba, were determined. EOs were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. EO‐B demonstrated higher activity against S. aureus and L. amazonensis; while a lower cytotoxicity on mammalian cells was observed. Both EOs displayed the same activity against Plasmodium falciparum, Trypanosoma cruzi, Trypanosoma brucei, and Leishmania infantum. Both EOs were inactive against Escherichia coli and Candida albicans. 相似文献
149.
Priscila L. dos Santos Fabrícia A. de Oliveira Micheli Luize B. Santos Luana Celina S. Cunha Michelle T. B. Lino Michelle F. S. de Oliveira Manuela O. M. Bomfim Angela Maria Silva Tatiana R. de Moura Amélia R. de Jesus Malcolm S. Duthie Steven G. Reed Roque P. de Almeida 《PLoS neglected tropical diseases》2016,10(1)
Background
Visceral leishmaniasis (VL) is a severe disease caused by infection with protozoa of the genus Leishmania. Classic VL is characterized by a systemic infection of phagocytic cells and an intense activation of the inflammatory response. It is unclear why 90% of infected individuals do not develop the disease while a minority develop the classical form. Furthermore, among those that develop disease, a small group progresses to more severe form that is unresponsive to treatment. The presence of inflammatory mediators in serum could theoretically help to control the infection. However, there is also a release of anti-inflammatory mediators that could interfere with the control of parasite multiplication. In this study, we took advantage of the spectrum of outcomes to test the hypothesis that the immune profile of individuals infected with Leishmania (L.) infantum is associated with the development and severity of disease.Methodology/Principal Findings
Sera from patients with confirmed diagnosis of VL were evaluated for the presence of numerous molecules, and levels compared with healthy control and asymptomatic infected individuals.Conclusions/Principal Findings
Although differences were not observed in LPS levels, higher levels of sCD14 were detected in VL patients. Our data suggest that L. infantum may activate the inflammatory response via CD14, stimulating a generalized inflammatory response with production of several cytokines and soluble molecules, including IFN-γ, IL-27, IL-10, IL-6 and sCD14. These molecules were strongly associated with hepatosplenomegaly, neutropenia and thrombocytopenia. We also observed that IL-6 levels greater than 200 pg/ml were strongly associated with death. Together our data reinforce the close relationship of IFN-γ, IL-10, IL-6, TNF-α and IL-27 in the immune dynamics of VL and suggest the direct participation of sCD14 in the activation of the immune response against L. infantum. 相似文献150.
The behavior of individual allocyclic chromosomes has been analyzed in lymphocytes of a sister and a brother with Bloom's syndrome. Of 4,633 diploid cells, 115 showed allocyclic chromosomes, and 74 of these had 44, 45 or 46 normal metaphase chromosomes accompanied by one or two allocyclic chromosomes. Of 56 tetraploid cells, 9 contained such chromosomes. The allocyclic chromosomes appeared pulverized or extended corresponding to S or G2 PCC. We have proposed the hypothesis that individual allocyclic chromosomes do not, as a rule, come from micronuclei, as has often been assumed, but have been left behind in their cycle. This would be caused by a mutation or deletion of a hypothetical coiling center situated near the centromere of each chromosome arm. The following observations agree with our explanation but less well or not at all with the idea of micronuclei: (1) In only 9.6% of the cells does the allocyclic chromosome lie at the edge of the metaphase plate. (2) In 24 cells a part of a chromosome is pulverized while the rest is in metaphase. (3) Both a pulverized and an extended chromosome were present in the same cell. (4) A pulverized acrocentric is often nose-to-nose with a normal D or G chromosome. (5) No allocyclic chromosomes corresponding to G1 PCC have been found in our material. (6) When a ring is replaced by an allocyclic chromosome, it is usually a member of a 46-chromosome complement. Furthermore, the occurrence of allocyclic chromosomes is correlated with that of other chromosome anomalies which do not follow a Poisson distribution. Allocyclic chromosomes are also more frequent (16%) in tetraploid than in diploid cells (2%). 相似文献