8 research outputs found
Innate Immune Responses of Pulmonary Epithelial Cells to Burkholderia pseudomallei Infection
10.1371/journal.pone.0007308PLoS ONE410
Azospirillum Genomes Reveal Transition of Bacteria from Aquatic to Terrestrial Environments
Fossil records indicate that life appeared in marine environments âŒ3.5 billion years ago (Gyr) and transitioned to terrestrial ecosystems nearly 2.5 Gyr. Sequence analysis suggests that âhydrobacteriaâ and âterrabacteriaâ might have diverged as early as 3 Gyr. Bacteria of the genus Azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. We obtained genome sequences of two Azospirillum species and analyzed their gene origins. While most Azospirillum house-keeping genes have orthologs in its close aquatic relatives, this lineage has obtained nearly half of its genome from terrestrial organisms. The majority of genes encoding functions critical for association with plants are among horizontally transferred genes. Our results show that transition of some aquatic bacteria to terrestrial habitats occurred much later than the suggested initial divergence of hydro- and terrabacterial clades. The birth of the genus Azospirillum approximately coincided with the emergence of vascular plants on land
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Chronic nicotine impairs the angiogenic capacity of human induced pluripotent stem cell-derived endothelial cells in a murine model of peripheral arterial disease.
ObjectiveLifestyle choices such as tobacco and e-cigarette use are a risk factor for peripheral arterial disease (PAD) and may influence therapeutic outcomes. The effect of chronic nicotine exposure on the angiogenic capacity of human induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) was assessed in a murine model of PAD.MethodsMice were exposed to nicotine or phosphate-buffered saline (PBS) for 28 days, followed by induction of limb ischemia and iPSC-EC transplantation. Cells were injected into the ischemic limb immediately after induction of hindlimb ischemia and again 7 days later. Limb perfusion was assessed by laser Doppler spectroscopy, and transplant cell survival was monitored for 14 days afterward using bioluminescence imaging, followed by histological analysis of angiogenesis.ResultsTransplant cell retention progressively decreased over time after implantation based on bioluminescence imaging, and there were no significant differences in cell survival between mice with chronic exposure to nicotine or PBS. However, compared with mice without nicotine exposure, mice with prior nicotine exposure had had an impaired therapeutic response to iPSC-EC therapy based on decreased vascular perfusion recovery. Mice with nicotine exposure, followed by cell transplantation, had significantly lower mean perfusion ratio after 14 days (0.47 ± 0.07) compared with mice undergoing cell transplantation without prior nicotine exposure (0.79 ± 0.11). This finding was further supported by histological analysis of capillary density, in which animals with prior nicotine exposure had a lower capillary density (45.9 ± 4.7 per mm2) compared with mice without nicotine exposure (66.5 ± 8.1 per mm2). Importantly, the ischemic limbs mice exposed to nicotine without cell therapy also showed significant impairment in perfusion recovery after 14 days, compared with mice that received PBS + iPSC-EC treatment. This result suggested that mice without chronic nicotine exposure could respond to iPSC-EC implantation into the ischemic limb by inducing perfusion recovery, whereas mice with chronic nicotine exposure did not respond to iPSC-EC therapy.ConclusionsTogether, these findings show that chronic nicotine exposure adversely affects the ability of iPSC-EC therapy to promote vascular perfusion recovery and angiogenesis in a murine PAD model
Comparative Effects of Basic Fibroblast Growth Factor Delivery or Voluntary Exercise on Muscle Regeneration after Volumetric Muscle Loss.
Volumetric muscle loss (VML) is associated with irreversibly impaired muscle function due to traumatic injury. Experimental approaches to treat VML include the delivery of basic fibroblast growth factor (bFGF) or rehabilitative exercise. The objective of this study was to compare the effects of spatially nanopatterned collagen scaffold implants with either bFGF delivery or in conjunction with voluntary exercise. Aligned nanofibrillar collagen scaffold bundles were adsorbed with bFGF, and the bioactivity of bFGF-laden scaffolds was examined by skeletal myoblast or endothelial cell proliferation. The therapeutic efficacy of scaffold implants with either bFGF release or exercise was examined in a murine VML model. Our results show an initial burst release of bFGF from the scaffolds, followed by a slower release over 21 days. The released bFGF induced myoblast and endothelial cell proliferation in vitro. After 3 weeks of implantation in a mouse VML model, twitch force generation was significantly higher in mice treated with bFGF-laden scaffolds compared to bFGF-laden scaffolds with exercise. However, myofiber density was not significantly improved with bFGF scaffolds or voluntary exercise. In contrast, the scaffold implant with exercise induced more re-innervation than all other groups. These results highlight the differential effects of bFGF and exercise on muscle regeneration
Estimating gestational age and its relation to the anthropometric status of newborns: a study comparing the Capurro and ultrasound methods with last menstrual period Estimativa da idade gestacional e sua relação com o estado antropomĂ©trico em recĂ©m-nascidos: uma comparação dos mĂ©todos Capurro e ultrassonogrĂĄfico com a data da Ășltima menstruação
OBJECTIVE: to assess the accuracy of the Capurro somatic and ultrasound methods, taking date of last menstruation as a reference point, for evaluating gestational age and anthropometric classification of term newborns. METHODS: a prevalence study was carried out involving 309 pregnant women and their term newborns, 92 of whom were small for gestational age and 217 appropriate sized for gestational age, at two public maternity hospitals in the Brazilian city of Salvador. The evaluation of the differences between the median gestational age according to the two methods was carried out using the non-parametric "Wilcoxon Signed-Rank Test." The accuracy of the methods for evaluating gestational age for the small for gestational age newborns was estimated by calculating the sensitivity, specificity, positive predictive value, negative predictive value and ROC (Receiver Operating Characteristic) curve. RESULTS: compared to ultrasound, the Capurro method overestimated the gestational age in newbornsof less than 39 weeks and underestimated it in older newborns. Ultrasound underestimated gestational agein newborns with more than 37 weeks. CONCLUSION: ultrasound was found to have greater sensitivity for prediction of small for age newborns (96.6%), while the Capurro method presented greater specificity (75.5%). The highest accuracy was obtained using ultrasound in the 41st gestational week (ROC=77.0%).<br>OBJETIVOS: avaliar a acurĂĄcia dos mĂ©todos fĂsico de Capurro e da ultrassonografia (USG), tomandocomo referĂȘncia o mĂ©todo da data da Ășltima menstruação (DUM), na avaliação da idade gestacional e classificação antropomĂ©trica de recĂ©m-nascidos (RN) a termo. MĂTODOS: estudo de prevalĂȘncia, envolvendo 309 puĂ©rperas e seus recĂ©m-nascidos a termo, sendo 92 pequenos para idade gestacional (PIG) e 217 adequados para idade gestacional (AIG), de duas maternidades pĂșblicas de Salvador. A avaliação das diferenças entre as medianas da idade gestacional segundo os mĂ©todos foi realizada utilizando-se o teste nĂŁo paramĂ©trico "Wilcoxon Signed-Rank Test." A acurĂĄcia dos mĂ©todos na avaliação da idade gestacional para o diagnĂłstico de RN PIG foi verificada atravĂ©s do cĂĄlculo da sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e curva ROC (Receiver Operating Characteristic). RESULTADOS: comparado Ă ultrassonografia, o mĂ©todo de Capurro superestimou a idade gestacional em recĂ©m-natos menores de 39 semanas e substimou a naqueles acima deste patamar. A USG substimou aidade gestacional em recĂ©m-nascidos com mais de 37 semanas. CONCLUSĂES: na predição de RN PIG, maior sensibilidade foi observada para a USG (96,6%) e maior especificidade para o Capurro (75,5%). Melhor acurĂĄcia foi observada para a USG na 41ÂȘ semana gestacional (ROC=77,0%)