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101.
An Olive latent virus 1 isolate designated GM6, obtained from a Portuguese olive tree, was characterized and the coat protein gene sequenced and analysed. The purified virus particles showed to be isometric with ca. 30 nm in diameter and contained a single-stranded RNA species with ca. 3.7 kb. The dsRNA profile obtained from infected tissues showed three major species with ca. 3.7, 1.5 and 1.3 kbp. SDS-PAGE analysis revealed a major peptide with an apparent molecular mass of 32 kDa identified as the coat protein. A viral genome region containing the coat protein gene was amplified by RT-PCR and the cDNA was cloned and sequenced. The coat protein gene revealed to be 813 nucleotides long and encode a peptide with 270 amino acid residues and an estimated Mr of 29,851. Alignment of the deduced amino acid sequence with that of other necroviruses showed a higher identity with OLV-1 tulip isolate (97.7%) than with OLV-1 citrus isolate (87.7%). The consensus pattern of the coat protein 'S' domain is conserved in GM6 isolate coat protein sequence, except in amino acid 151, leucine. This is the first report on the coat protein sequence of an OLV-1 olive isolate. 相似文献
102.
The patterns of exochorion ornaments on eggs of seven South American Lutzomyia sand fly species were analyzed by scanning electron microscopy (SEM): Lutzomyia (Lutzomyia) cruzi (Mangabeira 1938), Lutzomyia (Micropygomyia) evandroi (Costa Lima and Antunes 1936), L. (Nyssomyia) intermedia (Lutz and Neiva 1912), L. longipalpis (Lutz and Neiva 1912), L. migonei (Franca 1920), L. (Nyssomyia) neivai (Pinto 1926), and L. renei (Martins, Falcao, and Silva 1957). Different patterns were observed, which showed the distinction between some species. Egg ornaments in L. cruzi and L. longipalpis appear as single, parallel, unconnected ridges, whereas eggs of L. migonei appear as single, parallel, connected ridges. Eggs of L. (Nyssomyia) intermedia and L. (N.) neivai present a new variation of the single, unconnected, parallel ridges pattern: small tubercles are present, distributed between the ridges. Eggs of L. renei present an elliptical pattern, with most structures connected by straight ridges. Eggs of L. (M.) evandroi present a polygonal pattern, with alternate rows of small and large hexagons. Our data emphasize the advantages of the SEM approach in the study of the exochorion patterns of Lutzomyia eggs and in the distinction of the sand fly species. 相似文献
103.
Extraskeletal myxoid chondrosarcoma: a clinicopathologic, immunohistochemical, and ploidy analysis of 23 cases. 总被引:3,自引:0,他引:3
A M Oliveira T J Sebo J E McGrory T A Gaffey M G Rock A G Nascimento 《Modern pathology》2000,13(8):900-908
Twenty-three cases of extraskeletal myxoid chondrosarcoma, evaluated at the Mayo Clinic between 1968 and 1996, were studied for clinicopathologic features, immunohistochemical profile, Ki-67 activity, and ploidy status to identify adverse prognostic factors. Females and males were equally affected, and the median age at diagnosis was 50 years. The tumors were located mainly in the lower extremities (83%), and the median tumor size was 9.5 cm. Sixteen tumors showed low cellularity (70%), and eight tumors had high mitotic activity (more than two per 10 high-power fields). The tumors were immunoreactive for vimentin (89%), synaptophysin (72%), epithelial membrane antigen (28%), and S-100 protein (17%). Nine tumors were diploid, three aneuploid, and one tetraploid. Mean Ki-67 activity was 11% (range, 1 to 45%). The 10-year overall survival rate was 78%. On univariate analysis, tumor size > or = 10 cm, high cellularity, presence of anaplasia or rhabdoid features, mitotic activity more than two per 10 high-power fields, Ki-67 > or = 10%, and Ki-67 "hot spot" > or = 25% were associated with decreased metastasis-free or overall survival. Ploidy status was not associated with any adverse outcome. The presence of any of these adverse prognostic factors can indicate the possibility of a more aggressive behavior in extraskeletal myxoid chondrosarcoma, and a closer follow-up is suggested. 相似文献
104.
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106.
Nicolelis MA Ghazanfar AA Stambaugh CR Oliveira LM Laubach M Chapin JK Nelson RJ Kaas JH 《Nature neuroscience》1998,1(7):621-630
We used simultaneous multi-site neural ensemble recordings to investigate the representation of tactile information in three areas of the primate somatosensory cortex (areas 3b, SII and 2). Small neural ensembles (30-40 neurons) of broadly tuned somatosensory neurons were able to identify correctly the location of a single tactile stimulus on a single trial, almost simultaneously. Furthermore, each of these cortical areas could use different combinations of encoding strategies, such as mean firing rate (areas 3b and 2) or temporal patterns of ensemble firing (area SII), to represent the location of a tactile stimulus. Based on these results, we propose that ensembles of broadly tuned neurons, located in three distinct areas of the primate somatosensory cortex, obtain information about the location of a tactile stimulus almost concurrently. 相似文献
107.
Monoclonal antibodies directed against the Thy-1 molecule or the CD3 complex were used to analyze the activation of T cells from mice acutely infected with Trypanosoma cruzi. When stimulated with G7, a mitogenic anti-Thy-1 monoclonal antibody, spleen cells from infected mice showed a markedly reduced or absent response that could not be restored by varying the culture time or the antibody concentration. However, cells from acutely infected animals proliferated to 145-2C11, an anti-CD3 monoclonal antibody. Flow cytometric analysis showed that the impaired response to G7 could not be attributed to a lack of expression of Thy-1 or CD3. Indeed, G7 seemed to deliver a positive signal to the cells since the proliferative response was completely restored by the addition of PMA. Moreover, purified T cells from infected mice responded to G7 in the presence of accessory cells from uninfected animals. These results suggest that a defective co-stimulatory cell function could be involved in the immunosuppression. In addition, our data present evidence against a generalized T cell anergy in the acute phase of the disease, since CD3-mediated activation was normal. 相似文献
108.
Camila D. S. Barros Jomênica B. Livramento Margaret G. Mouro Elisa Mieko Suemitsu Higa Carlos T. Moraes Celia Harumi Tengan 《Nutrients》2021,13(2)
L-Arginine (L-ARG) supplementation has been suggested as a therapeutic option in several diseases, including Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like syndrome (MELAS), arguably the most common mitochondrial disease. It is suggested that L-ARG, a nitric oxide (NO) precursor, can restore NO levels in blood vessels, improving cerebral blood flow. However, NO also participates in mitochondrial processes, such as mitochondrial biogenesis, the regulation of the respiratory chain, and oxidative stress. This study investigated the effects of L-ARG on mitochondrial function, nitric oxide synthesis, and nitro-oxidative stress in cell lines harboring the MELAS mitochondrial DNA (mtDNA) mutation (m.3243A>G). We evaluated mitochondrial enzyme activity, mitochondrial mass, NO concentration, and nitro-oxidative stress. Our results showed that m.3243A>G cells had increased NO levels and protein nitration at basal conditions. Treatment with L-ARG did not affect the mitochondrial function and mass but reduced the intracellular NO concentration and nitrated proteins in m.3243A>G cells. The same treatment led to opposite effects in control cells. In conclusion, we showed that the main effect of L-ARG was on protein nitration. Lowering protein nitration is probably involved in the mechanism related to L-ARG supplementation benefits in MELAS patients. 相似文献
109.
Francisco A. O. Júnior Clara R. Ruiz Yohanna de Oliveira Marco A. V. Barros Alexandre S. Silva Maria S. B. Santos Vinícius J. B. Martins Camille M. Balarini Valdir A. Braga 《Nutrients》2021,13(3)
Exploring an alternative to improve the clinical management of hypertension, we tested the hypothesis that food supplementation with coconut oil (EVCO), alone or combined with aerobic exercise training, could exert an antihypertensive effect (primary outcome) in patients with stage 1 hypertension. Forty-five hypertensive volunteers of both genders participated in a placebo-controlled clinical trial. The volunteers were submitted to 24-hour ambulatory blood pressure monitoring, analysis of blood pressure variability (BPV), measurement of serum malondialdehyde (MDA) and nutritional assessment. Results indicate that EVCO consumption had no adverse effects. The supplementation did not increase the caloric intake compared with placebo, and the dietary constituents were similar between groups, except for the saturated fats, especially lauric acid. The analysis of blood pressure indicated absence of antihypertensive effect of EVCO alone or combined with physical training. Furthermore, no effects on blood pressure variability and oxidative stress were observed in the supplemented hypertensive patients. Thus, despite the results observed in pre-clinical studies, the current clinical study did not provide evidence to support the use of coconut oil as an adjuvant in the management of hypertension in humans. 相似文献
110.
Amanda Rodrigues Amorim Adegboye Danilo Dias Santana Pedro Paulo Teixeira dos Santos Paula Guedes Cocate Camila Benaim Maria Beatriz Trindade de Castro Michael Maia Schlüssel Gilberto Kac Berit Lilienthal Heitmann 《Nutrients》2021,13(3)
In this 2 × 2 factorial, outcome-assessor blinded, feasibility randomised trial we explored the effect of a non-pharmaceutical multi-component intervention on periodontal health and metabolic and inflammatory profiles among pregnant women with periodontitis receiving prenatal care in a Brazilian public health centre. 69 pregnant women (gestational age ≤20 weeks, T0) were randomly allocated into four groups: (1) fortified sachet (vitamin D and calcium) and powdered milk plus periodontal therapy during pregnancy (early PT) (n = 17); (2) placebo sachet and powdered milk plus early PT (n = 15); (3) fortified sachet and powdered milk plus late PT (after delivery) (n = 19); (4) placebo sachet and powdered milk plus late PT (n = 18). Third trimester (T1) and 6–8 weeks postpartum (T2) exploratory outcomes included periodontal health (% sites with bleeding on probing (BOP)), glucose, insulin, C-Reactive Protein, serum calcium and vitamin D. The mean BOP was significantly reduced in the early PT groups, while BOP worsened in the late PT groups. No significant effect of fortification on BOP was observed. Changes in glucose levels and variation on birthweight did not differ among groups This feasibility trial provides preliminary evidence for estimating the minimum clinically important differences for selected maternal outcomes. A large-scale trial to evaluate the interventions’ clinical benefits and cost-effectiveness is warranted. 相似文献