889 resultados para Colony morphology


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Bacteria phenotypically resembling members of the phylogenetically distinct planctomycete group of the domain Bacteria were isolated from postlarvae of the giant tiger prawn, Penaeus monodon. A selective medium designed in the light of planctomycete antibiotic resistance characteristics was used for this isolation. Planctomycetes were isolated from both healthy and monodon baculovirus-infected prawn postlarvae, The predominant colony type recovered from postlarvae regardless of viral infection status was nonpigmented. Other, less commonly observed types were pink or orange pigmented, A planctomycete-specific 16S rRNA-directed probe was designed and used to screen the isolates for their identity as planctomycetes prior to molecular phylogenetic characterization. 16S rRNA genes from nine prawn isolates together with two planctomycete reference strains (Planctomyces brasiliensis and Gemmata obscuriglobus) were sequenced and compared with reference sequences from the planctomycetes and other members of the domain Bacteria, Phylogenetic analyses and sequence signatures of the 16S rRNA genes demonstrated that the prawn isolates were members of the planctomycete group, Five representatives of the predominant nonpigmented colony type were members of the Pirellula group within the planctomycetes, as were three pink-pigmented colony type representatives. Homology values and tree topology indicated that representatives of the nonpigmented and pink-pigmented colony types formed two discrete clusters within the Pirellula group, not identical to any known Pirellula species, A sole representative of the orange colony type was a member of the Planctomyces group, virtually identical in 16S rDNA sequence to P. brasiliensis, and exhibited distinctive morphology.

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To date, several activating mutations have been discovered in the common signal-transducing subunit (h beta c) of the receptors for human granulocyte-macrophage colony-stimulating factor, interleukin-3, and interleukin-5. Two of these, Fl Delta and 1374N, result in a 37 amino acid duplication and a single amino acid substitution in the extracellular domain of h beta c, respectively. A third, V449E, results in a single amino acid substitution in the transmembrane domain, Previous studies comparing the activity of these mutants in different hematopoietic cell lines imply that the transmembrane and extracellular mutations act by different mechanisms and suggest the requirement for cell type-specific molecules in signalling. To characterize the ability of these mutant hpc subunits to mediate growth and differentiation of primary cells and hence investigate their oncogenic potential, we have expressed all three mutants in primary murine hematopoietic cells using retroviral transduction. It is shown that, whereas expression of either extracellular hpc mutant confers factor-independent proliferation and differentiation on cells of the neutrophil and monocyte lineages only, expression of the transmembrane mutant does so on these lineages as well as the eosinophil, basophil, megakaryocyte, and erythroid lineages, Factor-independent myeloid precursors expressing the transmembrane mutant display extended proliferation in liquid culture and in some cases yielded immortalized cell lines. (C) 1997 by The American Society of Hematology.

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Otitis media with effusion (OME) affects 28-38% of pre-school children, and it occurs due to the dysfunction of the auditory tube. Anatomical development of the auditory tube depends on the craniofacial growth and development. Deviations of normal. craniofacial. morphology and growth using cephatometric studies, may predict the evolution of otitis. Our goal in this paper is to determine if there are differences in craniofacial morphology between children with adenoid enlargement, with and without otitis media with effusion. This is a prospective study in which the sample consisted of 67 children (mate and female) from 5 to 10 years old. All patients presented chronic upper airway obstruction due to tonsil. and adenoid enlargement (>80% degree of obstruction). Thirty-three patients presented otitis media with effusion, for more than 3 months and 34 did not. The tatter composed the control group. Standardized lateral head radiographs were obtained for all. subjects. Radiographs were taken with patient positioned by a cephalostat and stayed with mandibles in centric occlusion and Lips at rest. Radiographs were digitalized and specific Landmarks were identified using a computer program Radiocef 2003, 5th edition. Measurements, angles and tines were taken of the basicranium, maxilla and mandible according to the modified Ricketts analysis. In addition, facial height and facial axis were determined. Children with otitis media with effusion present differences in the morphology of the face, regarding these measures: N-S (anterior cranial base length), N-ANS (upper facial height), ANS-PNS (size of the hard palate), Po-Or.N-Pog (facial depth), Ba-N.Ptm-Gn (facial axis), Go-Me (mandibular Length) and Vaia--Vaip (inferior pharyngeal airway). (C) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objective: To determine the effects of melatonin on rat endometrium morphology and embryo implantation. Design: Experimental study. Setting: Federal University of Sao Paulo, Brazil. Animal(s): Forty female rats. Intervention(s): GI: control, GII: sham-operated, GIII: pinealectomized, and GIV: pinealectomized rats that received melatonin during 3 months. The GI, GII, and Gin groups received the vehicle of melatonin (NaCl + ethanol). At the end of the treatment, the animals were killed during the estrous phase; the uterus was removed for morphometric analysis. Urine was collected for 6-sulfatoxymelatonin. Blood was collected for estrogen (E) and progesterone (P) level determinations. In a second experiment, female rats were used to evaluate the endometrial embryo implantation. Main Outcome Measure(s): Endometrial morphology and embryo implantation. Result(s): Gin presented the highest values for endometrial area and thickness index, number of endometrial glands, and eosinophils. The number of vessels of groups I, II, and IV was fewer than that of Gin. The highest number of eosinophils was detected in Gin in comparison to other groups. The implantation rate in Gin was the lowest of all groups. This implantation rate was significantly increased and restored toward normal in GIV. Conclusion(s): Our data suggested that, in nonphotoperiodic animals such as rats, melatonin may positively affect the endometrial morphology and improve embryo implantation.

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in humans, adverse pregnancy outcomes (low birth weight, prematurity, and intrauterine growth retardation) are associated with exposure to urban air pollution. Experimental data have also shown that such exposure elicits adverse reproductive outcomes. We hypothesized that the effects of urban air pollution on pregnancy outcomes could be related to changes in functional morphology of the placenta. To test this, future dams were exposed during pregestational and gestational periods to filtered or nonfiltered air in exposure chambers. Placentas were collected from near-term pregnancies and prepared for microscopical examination. Fields of view on vertical uniform random tissue slices were analyzed using stereological methods. Volumes of placental compartments were estimated, and the labyrinth was analyzed further in terms of its maternal vascular spaces, fetal capillaries, trophoblast, and exchange surface areas. From these primary data, secondary quantities were derived: vessel calibers (expressed as diameters), trophoblast thickness (arithmetic mean), and total and mass-specific morphometric diffusive conductances for oxygen of the intervascular barrier. Two-way analysis of variance showed that both periods of exposure led to significantly smaller fetal weights. Pregestational exposure to nonfiltered air led to significant increases in fetal capillary surface area and in total and mass-specific conductances. However, the calibers of maternal blood spaces were reduced. Gestational exposure to nonfiltered air was associated with reduced volumes, calibers, and surface areas of maternal blood spaces and with greater fetal capillary surfaces and diffusive conductances. The findings indicate that urban air pollution affects placental functional morphology. Fetal weights are compromised despite attempts to improve diffusive transport across the placenta.

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Objectives The subgenual prefrontal cortex (SGPFC) is an important brain region involved in emotional regulation and reward mechanisms Volumetric abnormalities in this region have been identified in adults with bipolar disorder but thus far not in pediatric cases We examined the volume of this brain region in subjects with pediatric bipolar disorder (PBD) and compared them to healthy controls Methods Fifty one children and adolescents (mean age +/- SD 13 2 +/- 2 9 y) with DSM-IV PBD and 41 (mean age +/- SD 13 7 +/- 2 7 y) healthy comparison subjects (HC) underwent 1 5 T structural magnetic resonance imaging (MRI) brain scans We traced the SGPFC manually and compared SGPFC gray matter volumes using analysis of covariance with age gender and intracranial volume as covariates We also examined the relationship of family history of affective disorders and medication status to SGPFC volumes Results SGPFC volumes were not significantly different in PBD and HC subjects However exploratory analysis showed PBD subjects who had one or more first degree relatives with mood disorders (n = 33) had significantly smaller left hemisphere SGPFC compared to HC (p = 003 Sidak corrected) Current usage of a mood stabilizer was significantly associated with larger right SGPFC volume in PBD (F = 4 82 df = 1/41 p = 0 03) Conclusion Subjects with PBD and a close family history of mood disorders may have smaller left SGPFC volumes than HC Mood stabilizing medication may also impact SGPFC size and could have masked more subtle abnormalities overall (C) 2010 Elsevier Ltd All rights reserved

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The rat posterodorsal medial amygdala (MePD) is a brain area in which gonadal hormones induce notable plastic effects in the density of dendritic spines. Dendritic spines are post-synaptic specializations whose shape and spacing change neuronal excitability. Our aim was to obtain new data on the dendritic spines morphology and density from MePD neurons using the carbocyanine dye Dil under confocal microscopy. In adult male rats, the dendritic spine density of the medial branches of the left MePD (mean +/- SD) was 1.15 +/- 0.67 spines/dendritic mu m. From the total sampled, approximately 53% of the spines were classified as thin, 22.5% as ""mushroom-like"", and 21.5% as stubby/wide. Other spine shapes (3%) included those ramified, with a filopodium-like or a gemule appearance, and others with a protruding spinule. Additional experiment joining Dil and synaptophysin (a pre-synaptic protein) labeling suggested synaptic sites on dendritic shafts and spines. Dendritic spines showed synaptophysin puncta close to their head and neck, although some spines had no evident labeled puncta on them or, conversely, multiple puncta appeared upon one spine. These results advance previous light microscopy results by revealing features and complexities of the dendritic spines at the same time that give new insight on the possible synaptic organization of the adult rat MePD. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

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Granulocyte-colony stimulating factor (G-CSF) is a current pharmacological approach to increase peripheral neutrophil counts after anti-tumor therapies. Pain is most relevant side effect of G-CSF in healthy volunteers and cancer patients. Therefore, the mechanisms of G-CSF-induced hyperalgesia were investigated focusing on the role of spinal mitogen-activated protein (MAP) kinases ERK (extracellular signal-regulated kinase). JNK (Jun N-terminal Kinase) and p38, and PI(3)K (phosphatidylinositol 3-kinase). G-CSF induced dose (30-300 ng/paw)-dependent mechanical hyperalgesia, which was inhibited by local post-treatment with morphine. This effect of morphine was reversed by naloxone (opioid receptor antagonist). Furthermore, G-CSF-induced hyperalgesia was inhibited in a dose-dependent manner by intrathecal pre-treatment with ERK (PD98059), JNK (SB600125), p38 (SB202190) or PI(3)K (wortmanin) inhibitors. The co-treatment with MAP kinase and PI(3)K inhibitors, at doses that were ineffective as single treatment, significantly inhibited G-CSF-induced hyperalgesia. Concluding, in addition to systemic opioids, peripheral opioids as well as spinal treatment with MAP kinases and PI(3)K inhibitors also reduce G-CSF-induced pain. (C) 2011 Elsevier Inc. All rights reserved.

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Successful reproduction requires that changes in plasma follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oxytocin (OT), estrogen (E-2) and progesterone (P-4) occur together with the display of maternal behaviors. Ovarian steroids and environmental stimuli can affect the dendritic spines in the rat hippocampus. Here, studying Wistar rats, it is described: (a) the sequential and concomitant changes in the hormonal profile of females at postpartum days (PP) 4, 8, 12, 16, 20 and 24, comparing to estrous cycle referential values; (b) the dendritic spine density in the stratum radiatum of CA1 (CA1-SR) Golgi-impregnated neurons in virgin females across the estrous cycle and in multiparous age-matched ones; and (c) the proportion of different types of spines in the CAI-SR of virgin and postpartum females, both in diestrus. Plasma levels of gonadotrophins and ovarian hormones remained low along PP while LH increased and PRL decreased near the end of the lactating period. The lowest dendritic spine density was found in virgin females in estrus when compared to diestrus and proestrus phases or to postpartum females in diestrus (p < 0.03). Other comparisons among groups were not statistically significant (p > 0.4). There were no differences in the proportions of the different spine types in nulliparous and postpartum females (p > 0.2). Results suggest that medium layer CA1-SR spines undergo rapid modifications in Wistar females across the estrous cycle (not quite comparable to Sprague-Dawley data or to hormonal substitutive therapy following ovariectomy), but persistent effects of motherhood on dendritic spine density and morphology were not found in this area. (c) 2008 Elsevier Ireland Ltd. All rights reserved.

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The vagus nerve is an important component of the efferent arm of the baroreflex. Blood pressure levels as well as baroreflex control of circulation are significantly different in male and female spontaneously hypertensive rats (SHR). We proposed to investigate the morphometric differences between genders using the vagus nerve of SHR. Adult animals (20 weeks old) were anesthetized and had their arterial pressure (AP) and heart rate (HR) recorded by a computerized system. The rats were then systemically perfused with a fixative solution and had their cervical vagi nerves prepared for light microscopy. Proximal and distal segments of the left and right vagi nerves were evaluated for morphometric parameters including fascicle area and diameter, myelinated fiber number, density, area and diameter. Comparisons were made between sides and segments on the same gender as well as between genders. Differences were considered significant when p<0.05. Male SHR had significantly higher AP and HR. Morphometric data showed no differences between the same levels of both sides and between segments on the same side for male and female rats. In addition, no significant morphometric differences were observed when genders were compared. This is the first description of vagus nerve morphometry in SHR indicating that gender differences in AP and HR cannot be attributed to dissimilarities in vagal innervation of the heart. These data provide a morphological basis for further studies involving functional investigations of the efferent arm of the baroreflex in hypertension. (C) 2007 Elsevier B.V. All rights reserved.

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Objectives: To evaluate the influence of the morphology of the first polar body (PB) on intracytoplasmic sperm injection (ICSI) outcomes. Methods: The morphology of the first PB was assessed in 3177 metaphase 11 oocytes and classified as: intact and normal size, fragmented, or enlarged size. The rates of fertilization, cleavage, and embryo quality were evaluated on day 2. Results: The rates of fertilization, cleavage, and formation of good quality embryos resulting from the insemination of oocytes with an enlarged first PB (20.7%, 18.7%, and 5.0%, respectively) were significantly lower than those for oocytes with an intact first PB of normal size (70.8%, 62.5%, and 19%, respectively) or a fragmented first PB (69.7%, 60.5%, and 17.1%, respectively). Rates did not differ significantly between oocytes with an intact first PB of normal size and oocytes with a fragmented first PB (P>0.05). Conclusions: The presence of an enlarged PB is related to poorer rates of fertilization, cleavage, and top quality embryos. However, identification of first PB fragmentation does not seem to interfere with ICSI outcomes. (C) 2008 International Federation ofGynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

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Background. Morphological and dentofacial alterations have been attributed to impaired respiratory function. Objective. To examine the influence of mouth breathing (MB) on children facial morphology before and after adenoidectomy or adenotonsillectomy. Methods. Thirty-three MB children who restored nasal breathing (NB) after surgery and 22 NB children were evaluated. Both groups were submitted to lateral cephalometry, at time 1 (T1) before and at time 2 (T2) 28 months on average postoperatively. Results. Comparison between the MB and NB groups at T1 showed that mouth breathers had higher inclination of the mandibular plane; more obtuse gonial angle; dolichofacial morphology; and a decrease in the total and inferior posterior facial heights. Twenty-eight months after the MB surgical intervention, they still presented a dolichofacial morphologic pattern. During this period, MB altered the face growth direction and decreased their mandible plane inclination, with reduction in the SN.GoGn, PP.MP, SNGn, and ArGo.GoMe parameters as well as an increase in BaN.PtGn. Conclusion. After the MB rehabilitation, children between 3 and 6 years old presented significant normalization in the mandibular growth direction, a decrease in the mandible inclination, and an increase in the posterior facial height. Instead, they still persisted with a dolichofacial pattern when compared with nasal breathers.

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Despite numerous literature reports on the morphometry of the myelinated fibers of phrenic nerves in rats, a systematic study of the longitudinal and lateral symmetry of the unmyelinated fibers morphometry is not available. In this study, we have undertaken ultrastructural and morphometric studies of the phrenic nerve in adult rats, assessing two different levels (proximal and distal) from both right and left sides. Phrenic nerves of adult male Wistar rats were prepared for epoxy resin embedding and transmission electron microscopy. Morphometric analysis was performed with the aid of computer software, which took into consideration the unmyelinated fiber number, density, area, and diameter, as well as ratio between myelinated and unmyelinated fibers, and the percentage of the fascicular area occupied by the myelinated and unmyelinated fibers. Comparison of data from proximal and distal segments on the same side and from the same levels between sides was performed. Differences were considered significant when P < 0.05. The most important finding is that morphometric parameters of the phrenic nerve unmyelinated fibers in adult rats are both longitudinally and laterally symmetric. This study adds important morphometric information about the unmyelinated fibers of the phrenic nerves in adult rats for proximal and distal levels on both sides of the animal. Anat Rec, 292:513-517, 2009. (C) 2008 Wiley-Liss, Inc.