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861.
Franciele Cabral Pinheiro Rodrigo Ligabue-Braun Ana Cecília Menezes de Siqueira Camila Matuella Carolina Fischinger Moura de Souza Fabíola Paoli Monteiro Fernando Kok Ida Vanessa Doederlein Schwartz Fernanda Sperb-Ludwig 《Genetics and molecular biology》2021,44(2)
Fructose-1,6-bisphosphatase (FBPase) deficiency is a rare inborn error of fructose metabolism caused by pathogenic variants in the FBP1 gene. As gluconeogenesis is affected, catabolic episodes can induce ketotic hypoglycemia in patients. FBP1 analysis is the most commonly used approach for the diagnosis of this disorder. Herein, a Brazilian patient is reported. The proband, a girl born to a consanguineous couple, presented with severe hypoglycemia crisis in the neonatal period. At the age 17 months, presented a new crisis accompanied by metabolic acidosis associated with a feverish episode. Genetic analysis was performed by next-generation sequencing (NGS), identifying the :c.611_614del variant in homozygosis in the FBP1 gene. In silico analysis and 3D modeling were performed, suggesting that this variant is associated with a loss of sites for substrate and Mg2+ binding and for posttranslational modifications of FBPase. The c.611_614del variant is located in a repetitive region of the FBP1 gene that appears to be a hotspot for mutational events. This frameshift creates a premature termination codon in the last coding exon which escapes the nonsense-mediated decay mechanism, according to in silico analysis. This variant results in an intrinsically disordered protein with loss of substrate recognition and post-translational modification sites. NM_000507.3相似文献
862.
J S Fortunato M J Pinheiro M C Monteiro M A Rodrigues I Amaral 《Journal of nuclear biology and medicine (Turin, Italy : 1991)》1991,35(2):105-110
The platelet (Plt) contribution to cardiovascular events triggered by adrenergic stress is supported by some experimental and necropsy data, but a cause and effect link and mechanism have not yet been clearly demonstrated. Adrenergic stress was simulated by three successive adrenaline (A) injections (80 micrograms/kg) in anesthetized dogs previously infused with indium111 labelled Plt (111In-Plt) for a gamma-camera study. Adrenaline induced an acute and significant decrease in the Plt aggregation ratio (PAR) and a parallel decrease in the Plt count as well as in the circulating 111In-Plt, mirroring a significant and persistent Plt sequestration mainly in the liver and spleen. The long-lasting and significant decrease in the circulating Plt count observed 15 min after each A injection can be explained by a persistent retention of Plt. Further studies are in progress in order to disclose if this corresponds to platelet microaggregate embolization in microvessels of the organs so far analysed. If this postulate can be confirmed the hypothesis of an adrenergic stress triggering of ischemic events will be justified. 相似文献
863.
This paper reports the discovery of an unusual population of Syagrus cocoides Martius located in the municipality of Barra do Corda, state of Maranhão, northeastern Brazil. The most interesting characteristic of this population is the high number of individuals with branched stems. Sampling showed that 16.12% of the population consisted of bifurcate adult individuals and 14.17% were bifurcate seedlings. The branching phenomenon in palms is reviewed, anc competing hypotheses are discussed to explain the branching in Syagrus cocoides and its ecological and evolutionary significance. We conclude that the most likely type of branching is by dichotomy. 相似文献
864.
de Souza Marcelo Claro Habermann Gustavo do Amaral Cárita Liberato Rosa Annylory Lima Pinheiro Marcelo Henrique Ongaro Da Costa Fernando Batista 《Plant and Soil》2017,416(1-2):377-389
Plant and Soil - Alterations in root growth and rhizosphere processes in maize (Zea mays L.) occur under phosphorus (P) deficiency, but the dynamics of root morphological and physiological... 相似文献
865.
866.
David C. Jenkins David S. Pearson Andrew Harvey Ian D. Sylvester Michael A. Geeves Teresa J. T. Pinheiro 《European biophysics journal : EBJ》2009,38(5):625-635
The conversion of the cellular form of the prion protein (PrPC) to an altered disease state, generally denoted as scrapie isoform (PrPSc), appears to be a crucial molecular event in prion diseases. The details of this conformational transition are not fully
understood, but it is perceived that they are associated with misfolding of PrP or its incapacity to maintain the native fold
during its cell cycle. Here we present a tryptophan mutant of PrP (F198W), which has enhanced fluorescence sensitivity to
unfolding/refolding transitions. Equilibrium folding was studied by circular dichroism and fluorescence. Pressure-jump experiments
were successfully applied to reveal rapid submillisecond folding events of PrP at temperatures not accessed before.
D. C. Jenkins and D. S. Pearson contributed equally. 相似文献
867.
Marcelo Antonio Amaro Pinheiro Marcio Camargo Araujo João Maria Helena Arruda Leme Akeme Milena Ferreira Matsunaga Juliana Priscila Piva Rio Patricio Hernáez 《Invertebrate reproduction & development.》2017,61(2):78-89
Petrolisthes armatus (Gibbes, 1850) life history was evaluated based on growth and reproduction. Specimens were captured at Ubatuba (Brazil), identified, sexed and measured: carapace (CL, length; CW, width), larger cheliped propodus (PL, length; PW, width; and PH, height), and 2th and 5th abdominal somite (AW2 and AW5, width). Relative growth was studied using CL as independent variable and its relation with other variables (dependents), to estimate puberty size and morphological maturity. Fecundity was represented by number of eggs vs. body size CL, with a better fit using a power function. Considering the 257 specimens analyzed, males were larger than females, and the overall sex ratio was 1:1, with some differences among size classes. Maturity (puberty size) was revealed by: AW2 × CL (males: 8.6 mm CL; females: 7.6 mm CL); and AW5 × CL (7.1 and 7.6 mm CL, respectively). Reproduction was continuous, but more intense in rainy season and recruitment occurring in dry season. Fecundity of this species was 228 ± 163 eggs, with better fit by a power function (R2 = 0.72). Maturity size and growth differed when a pristine area (Ubatuba) was compared with a polluted area (São Sebastião), in the same Brazilian area (São Paulo State). 相似文献
868.
Icaro dos Santos Dieter Haemmerich Cleber da Silva Pinheiro Adson Ferreira da Rocha 《Biomedical engineering online》2008,7(1):21
Background
One of the current shortcomings of radiofrequency (RF) tumor ablation is its limited performance in regions close to large blood vessels, resulting in high recurrence rates at these locations. Computer models have been used to determine tissue temperatures during tumor ablation procedures. To simulate large vessels, either constant wall temperature or constant convective heat transfer coefficient (h) have been assumed at the vessel surface to simulate convection. However, the actual distribution of the temperature on the vessel wall is non-uniform and time-varying, and this feature makes the convective coefficient variable. 相似文献869.
D L da Mota L L George P P Pinheiro N L Pinheiro 《Gegenbaurs morphologisches Jahrbuch》1989,135(2):367-377
The intestinal of the 3-toed sloth, Bradypus tridactylus, was studied macroscopically, with light microscope and with histochemical methods for mucosubstances. Macroscopically, the inner surface of the duodenum shows longitudinal and circular folds. There is no caecum, nor appendix. The large intestine consists of a short colon and a large rectal pouch, which has a thick wall. The mucosa of the small intestine has long leaf-shaped villi covered with columnar epithelium having a well developed striated border, and the goblet cells are scattered among the columnar cells. An association between neutral and acidic mucosubstances was detected in the goblet cells. The duodenal (Brunner's) glands are confined exclusively in the lamina propria of the duodenum. No Paneth cells were observed in the crypt lining. Argyrophil and argentaffin cells were found in the entire length of the intestine. The large intestine does not possess villi, but many goblet cells were observed in its mucosa. 相似文献
870.
Mahdieh Ahmadi Ahmad Noori Bita Kalvani Neitali Marcelo Antonio Amaro Pinheiro 《Acta zoologica》2023,104(2):176-184
The purpose of this study was to investigate the relative growth and sexual dimorphism in the hermit crab Clibanarius signatus. The evaluation was done with 955 specimens (494 males, 251 females, and 210 intersexes) captured in Persian Gulf (Iran) during January to December 2015. Animals were submitted to measurements related to weight (BW, total wet weight) and body size related to cephalic shield (SW, width; and SL, length) and propodus of both chelipeds (CPL, length; and CPW, width). Males were larger and heavier than females and intersexes. Both males and females showed a negative allometric growth for the SL–BW and SL–SW relationships, but a positive allometric growth to intersex specimens. To SL–CPL relationship, a negative allometric growth was confirmed in males and females independent of the laterality of the CPL, whereas a contrast was verified in intersexes, with a positive allometric growth occurred for both hands. To SL–CPW relationship, a negative allometric growth (b < 1) occurred in females, independent of the laterality of the CPW, while in males, a positive allometric pattern was confirmed. In intersexes, this relationship was positive except for the right CPW which was isometric. Sexual dimorphism was evident in Clibanarius signatus, with males being the largest and females the smallest specimens in the population. 相似文献