共查询到20条相似文献,搜索用时 15 毫秒
1.
Albert Blarer Daniel L. Nickrent Peter K. Endress 《Plant Systematics and Evolution》2004,245(1-2):119-142
Comparative studies on floral morphology, anatomy, and histology were performed to identify shared features of the genera of Apodanthaceae (Rafflesiales): Apodanthes, Pilostyles, and Berlinianche. Berlinianche was studied for the first time in detail and its affinity to Apodanthaceae was confirmed. It has a previously undescribed hair cushion on the inner perianth organs and inaperturate pollen. Shared features of members of Apodanthaceae are: unisexual flowers; three (or four) alternating di-/tetra- or tri-/hexamerous whorls of scales of which the inner one or two correspond to a perianth; a synandrium with pollen sacs typically arranged in two rings; opening by a dehiscence line between the two rings of pollen sacs; large vesicular hairs above the synandrium; a gynoecium with four united carpels; inferior and unilocular ovaries with four parietal placentae, ovules tenuinucellate, anatropous with two well developed integuments, oriented in various directions; a nectary disk. Apodanthaceae share some special structural features with Malvales. 相似文献
2.
Lenka Belinova Hana Kahleova Hana Malinska Ondrej Topolcan Jindra Vrzalova Olena Oliyarnyk Ludmila Kazdova Martin Hill Terezie Pelikanova 《PloS one》2014,9(9)
Background
The intake of meat, particularly processed meat, is a dietary risk factor for diabetes. Meat intake impairs insulin sensitivity and leads to increased oxidative stress. However, its effect on postprandial gastrointestinal hormone (GIH) secretion is unclear. We aimed to investigate the acute effects of two standardized isocaloric meals: a processed hamburger meat meal rich in protein and saturated fat (M-meal) and a vegan meal rich in carbohydrates (V-meal). We hypothesized that the meat meal would lead to abnormal postprandial increases in plasma lipids and oxidative stress markers and impaired GIH responses.Methods
In a randomized crossover study, 50 patients suffering from type 2 diabetes (T2D) and 50 healthy subjects underwent two 3-h meal tolerance tests. For statistical analyses, repeated-measures ANOVA was performed.Results
The M-meal resulted in a higher postprandial increase in lipids in both groups (p<0.001) and persistent postprandial hyperinsulinemia in patients with diabetes (p<0.001). The plasma glucose levels were significantly higher after the V-meal only at the peak level. The plasma concentrations of glucose-dependent insulinotropic peptide (GIP), peptide tyrosine-tyrosine (PYY) and pancreatic polypeptide (PP) were higher (p<0.05, p<0.001, p<0.001, respectively) and the ghrelin concentration was lower (p<0.001) after the M-meal in healthy subjects. In contrast, the concentrations of GIP, PYY and PP were significantly lower after the M-meal in T2D patients (p<0.001). Compared with the V-meal, the M-meal was associated with a larger increase in lipoperoxidation in T2D patients (p<0.05).Conclusion/Interpretation
Our results suggest that the diet composition and the energy content, rather than the carbohydrate count, should be important considerations for dietary management and demonstrate that processed meat consumption is accompanied by impaired GIH responses and increased oxidative stress marker levels in diabetic patients.Trial Registration
ClinicalTrials.gov NCT01572402相似文献3.
The control of transmembrane helix transverse position in membranes by hydrophilic residues 总被引:1,自引:0,他引:1
The ability of hydrophilic residues to shift the transverse position of transmembrane (TM) helices within bilayers was studied in model membrane vesicles. Transverse shifts were detected by fluorescence measurements of the membrane depth of a Trp residue at the center of a hydrophobic sequence. They were also estimated from the effective length of the TM-spanning sequence, derived from the stability of the TM configuration under conditions of negative hydrophobic mismatch. Hydrophilic residues (at the fifth position in a 21-residue hydrophobic sequence composed of alternating Leu and Ala residues and flanked on both ends by two Lys) induced transverse shifts that moved the hydrophilic residue closer to the membrane surface. At pH 7, the dependence of the extent of shift upon the identity of the hydrophilic residue increased in the order: L < GYT < RH < S < P < K < EQ < N < D. By varying pH, shifts with ionizable residues fully charged or uncharged were measured, and the extent of shift increased in the order: L < GYHoT < EoR < S < P < K+< QDoH+ < NE– < D–. The dependence of transverse shifts upon hydrophilic residue identity was consistent with the hypothesis that shift magnitude is largely controlled by the combination of side chain hydrophilicity, ionization state, and ability to position polar groups near the bilayer surface (snorkeling). Additional experiments showed that shift was also modulated by the position of the hydrophilic residue in the sequence and the hydrophobicity of the sequence moved out of the bilayer core upon shifting. Combined, these studies show that the insertion boundaries of TM helices are very sensitive to sequence, and can be altered even by weakly hydrophilic residues. Thus, many TM helices may have the capacity to exist in more than one transverse position. Knowledge of the magnitudes of transverse shifts induced by different hydrophilic residues should be useful for design of mutagenesis studies measuring the effect of transverse TM helix position upon function. 相似文献
4.
Cedric Le Maréchal Jian-Min Chen Isabelle Quéré Odile Raguénès Claude Férec Jean Auroux 《BMC genetics》2001,2(1):19-4
Background
R122, the primary autolysis site of the human cationic trypsinogen (PRSS1), constitutes an important "self-destruct" or "fail-safe" defensive mechanism against premature trypsin activation within the pancreas. Disruption of this site by a missense mutation, R122H, was found to cause hereditary pancreatitis. In addition to a c.365G>A (CGC>CAC) single nucleotide substitution, a c.365~366GC>AT (CGC>CAT) gene conversion event in exon 3 of PRSS1 was also found to result in a R122H mutation. This imposes a serious concern on the genotyping of pancreatitis by a widely used polymerase chain reaction-restriction fragment length polymorphism assay, which could only detect the commonest c.365G>A variant. 相似文献5.
Background
Various hard face models are commonly used to evaluate the efficiency of aerosol face masks. Softer more realistic “face” surface materials, like skin, deform upon mask application and should provide more relevant in-vitro tests. Studies that simultaneously take into consideration many of the factors characteristic of the in vivo face are lacking. These include airways, various application forces, comparison of various devices, comparison with a hard-surface model and use of a more representative model face based on large numbers of actual faces.Aim
To compare mask to “face” seal and aerosol delivery of two pediatric masks using a soft vs. a hard, appropriately representative, pediatric face model under various applied forces.Methods
Two identical face models and upper airways replicas were constructed, the only difference being the suppleness and compressibility of the surface layer of the “face.” Integrity of the seal and aerosol delivery of two different masks [AeroChamber (AC) and SootherMask (SM)] were compared using a breath simulator, filter collection and realistic applied forces.Results
The soft “face” significantly increased the delivery efficiency and the sealing characteristics of both masks. Aerosol delivery with the soft “face” was significantly greater for the SM compared to the AC (p< 0.01). No statistically significant difference between the two masks was observed with the hard “face.”Conclusions
The material and pliability of the model “face” surface has a significant influence on both the seal and delivery efficiency of face masks. This finding should be taken into account during in-vitro aerosol studies. 相似文献6.
Background
Our aim was to estimate the effect of two myostatin (MSTN) mutations in Norwegian White Sheep, one of which is close to fixation in the Texel breed.Methods
The impact of two known MSTN mutations was examined in a field experiment with Norwegian White Sheep. The joint effect of the two MSTN mutations on live weight gain and weaning weight was studied on 644 lambs. Carcass weight gain from birth to slaughter, carcass weight, carcass conformation and carcass fat classes were calculated in a subset of 508 lambs. All analyses were carried out with a univariate linear animal model.Results
The most significant impact of both mutations was on conformation and fat classes. The largest difference between the genotype groups was between the wild type for both mutations and the homozygotes for the c.960delG mutation. Compared to the wild types, these mutants obtained a conformation score 5.1 classes higher and a fat score 3.0 classes lower, both on a 15-point scale.Conclusions
Both mutations reduced fatness and increased muscle mass, although the effect of the frameshift mutation (c.960delG) was more important as compared to the 3''-UTR mutation (c.2360G>A). Lambs homozygous for the c.960delG mutation grew more slowly than those with other MSTN genotypes, but had the least fat and the largest muscle mass. Only c.960delG showed dominance effects. 相似文献7.
Background
Mutations in the PRRT2 gene have been identified as the major cause of benign familial infantile epilepsy (BFIE), paroxysmal kinesigenic dyskinesia (PKD) and infantile convulsions with paroxysmal choreoathetosis/dyskinesias (ICCA). Here, we analyzed the phenotypes and PRRT2 mutations in Chinese families with BFIE and ICCA.Methods
Clinical data were collected from 22 families with BFIE and eight families with ICCA. PRRT2 mutations were screened using PCR and direct sequencing.Results
Ninety-five family members were clinically affected in the 22 BFIE families. During follow-up, two probands had one seizure induced by diarrhea at the age of two years. Thirty-one family members were affected in the eight ICCA families, including 11 individuals with benign infantile epilepsy, nine with PKD, and 11 with benign infantile epilepsy followed by PKD. Two individuals in one ICCA family had PKD or ICCA co-existing with migraine. One affected member in another ICCA family had experienced a fever-induced seizure at 7 years old. PRRT2 mutations were detected in 13 of the 22 BFIE families. The mutation c.649_650insC (p.R217PfsX8) was found in nine families. The mutations c.649delC (p.R217EfsX12) and c.904_905insG (p.D302GfsX39) were identified in three families and one family, respectively. PRRT2 mutations were identified in all eight ICCA families, including c.649_650insC (p.R217PfsX8), c.649delC (p.R217EfsX12), c.514_517delTCTG (p.S172RfsX3) and c.1023A?>?T (X341C). c.1023A?>?T is a novel mutation predicted to elongate the C-terminus of the protein by 28 residues.Conclusions
Our data demonstrated that PRRT2 is the major causative gene of BFIE and ICCA in Chinese families. Site c.649 is a mutation hotspot: c.649_650insC is the most common mutation, and c.649delC is the second most common mutation in Chinese families with BFIE and ICCA. As far as we know, c.1023A?>?T is the first reported mutation in exon 4 of PRRT2. c.649delC was previously reported in PKD, ICCA and hemiplegic migraine families, but we further detected it in BFIE-only families. c.904_905insG was reported in an ICCA family, but we identified it in a BFIE family. c.514_517delTCTG was previously reported in a PKD family, but we identified it in an ICCA family. Migraine and febrile seizures plus could co-exist in ICCA families.8.
Background
Bacterial signal transduction mechanism referred to as a "two component regulatory systems" contributes to the overall adaptability of the bacteria by regulating the gene expression. Osmoregulation is one of the well-studied two component regulatory systems comprising of the sensor, EnvZ and the cognate response regulator, OmpR, which together control the expression of OmpC and OmpF porins in response to the osmolyte concentration. 相似文献9.
Purpose
To determine whether hyperglycemic levels as determined from high hemoglobin A1c (HbA1c) levels influence intraocular pressure (IOP) in patients with non-proliferative diabetic retinopathy (NPDR).Methods
A retrospective chart review was performed on subjects with a diagnosis of NPDR and a corresponding HbA1c level measured within 90 days before or after an IOP measurement over a two-year period. Exclusion criteria included a diagnosis of glaucoma or treatment with IOP lowering medications or oral or topical steroids.Results
Using 14.5mmHg as a baseline mean value for IOP, 42 subjects had an IOP < 14.5mmHg and mean HbA1c of 8.1±1.1, while 72 subjects had an IOP ≥ 14.5mmHg and a mean HbA1c of 9.0±2.1. Although there was an overlap in the confidence intervals, a significant difference (P = 0.01) in the mean HbA1c level was observed in regression analysis between the two groups. Importantly, diabetic subjects with elevated HbA1c levels rarely (<1%) exhibited reduced IOP levels.Conclusions
Diabetic subjects with elevated HbA1c levels exhibited significantly higher IOPs compared to those with lower HbA1c levels. Findings from this study indicate an association between hyperglycemia and elevated IOP and that poor glycemic control may contribute to increased IOP levels in long-term diabetic patients. 相似文献10.
11.
Lu Yin Jiaan Zhu Qin Xue Niansong Wang Zhenlong Hu Yunxia Huang Fang Liu Bing Hu 《PloS one》2014,9(5)
Objective
To assess the value of MicroPure, a new ultrasound image processing technique, in identifying microcalcifications (formed by monosodium urate crystals) in the first metatarsophalangeal joints attacked by gout compared to gray-scale ultrasound images.Materials and Methods
Thirty-six patients who fulfilled the study inclusion criteria underwent gray-scale ultrasound and MicroPure examinations of the first metatarsophalangeal joints attacked by gout. Static images of the target areas were acquired using gray-scale ultrasound and MicroPure. Two independent and blinded investigators analyzed the images to determine the number of microcalcifications and to score for image quality and artifacts.Results
The two investigators observed significantly more microcalcifications with MicroPure compared to gray-scale ultrasound (ρ<0.001). The level of agreement between the investigators consistently increased from gray-scale ultrasound to MicroPure imaging (gray-scale interclass correlation coefficient of 0.69 vs. MicroPure interclass correlation coefficient of 0.81). One investigator preferred the MicroPure image quality over gray-scale ultrasound (ρ<0.001), but the other investigator disagreed (ρ<0.001). Both investigators observed fewer artifacts with MicroPure than with gray-scale ultrasound (ρ<0.009).Conclusion
MicroPure imaging identified significantly more microcalcifications than gray-scale ultrasound. 相似文献12.
Objective
This study was designed to examine the relationship between shortened activated partial thromboplastin time (APTT) and increased fibrinogen values with diabetes mellitus.Methods
APTT, prothrombin time (PT), fibrinogen, fasting plasma glucose (FPG) and glycosylated hemoglobin A1c (HbA1c) levels were measured in 1,300 patients. Patients were divided into three groups according to their HbA1c and FPG levels.Results
When participants were grouped according to their HbA1c levels, we found significantly shorter APTT values (26.9±5.6 s) and increased fibrinogen levels (3.1, 1.9–6.3 g/L) in the diabetes group when compared with the other two groups. When participants were grouped according to their FPG levels, we found significantly shorter APTT values (26.9±6.2 s) and increased fibrinogen levels (3.1, 1.8–6.2 g/L) in the diabetes group when compared with the euglycemic group.Conclusions
Shorter APTT and increased fibrinogen levels might be useful hemostatic markers in patients with diabetes and in patients at high risk for diabetes. 相似文献13.
Yunxian Zhou 《PloS one》2014,9(9)
Background and Purpose
Transnational nurse migration is a growing phenomenon. This study explored the experiences of China-educated nurses working in Australia.Design
Using a constructivist grounded theory method, 46 in-depth interviews were conducted with 28 China-educated nurses in two major cities in Australia.Results
The core category emerged was “reconciling different realities”. Three phases of reconciling were conceptualised: realising, struggling, and reflecting. Realising refers to an awareness of the discrepancies between different realities. Struggling reflects the dilemma of the “middle position” and how being situated as “the other” is experienced. Reflecting is the process of making sense of the experience and rationalising the gains and losses associated with immigration.Conclusions
This study produced a theoretical understanding of the experience of China-educated nurses working in Australia. The findings not only inform Chinese nurses who wish to migrate but contribute to the implementation of more effective support services for immigrant nurses. 相似文献14.
Fioretto JR Martin JG Kurokawa CS Carpi MF Bonatto RC Ricchetti SM de Moraes MA Padovani CR 《Cytokine》2008,43(2):160-164
Objectives. To examine the behavior of interleukin-6 (IL-6) and procalcitonin (PCT) and verify whether they can be used to differentiate children with septic conditions. Methods. Septic children aged between 28 days and 14 years, prospectively enrolled from 01/2004 to 12/2005, were divided into sepsis (SG; n = 47) and septic shock (SSG; n = 43) groups. IL-6 and PCT were measured at admission (T0) and 12 h later (T12h). PCT results were classed as: 0.5 ng/mL = sepsis unlikely; 0.5 to <2 = sepsis possible; 2 to <10 = systemic inflammation; 10 = septic shock. Results. Ninety children were included. At T0, there was a higher frequency of SSG with higher PCT compared with SG [SSG: 30 (69.7%) > SG: 14 (29.8%); p < 0.05]. Similar results were observed at T12h. PRISM was significantly higher for SSG patients with higher PCT than SG patients. At T0, IL-6 levels were higher in SSG [SSG: 213.10 (10.85–396.70) > SG: 63.21 (0.86–409.82); p = 0.001], but not statistically different at T12h. IL-6 levels positively correlated with PRISM score in SSG patients at admission (p = 0.001; r = 0.86). Conclusion. PCT and IL-6 appear to be helpful in early assessment of pediatric sepsis, are of diagnostic value at admission, and are related to disease severity. 相似文献
15.
Omar Hammouda Hamdi Chtourou Asma Aloui Henda Chahed Choumous Kallel Abdelhedi Miled Karim Chamari Anis Chaouachi Nizar Souissi 《PloS one》2013,8(11)
Objective
To examine the time-of-day and Ramadan fasting (RF) effects on serum apolipoprotein-AI (Apo-AI) and B (Apo-B), lipoprotein particles-a (Lp-a), high-sensitive C-reactive-protein (hs-CRP), and homocysteine (Hcy) during the Yo-Yo intermittent recovery test (YYIRT).Design
Performance and biochemical measures were completed at two times-of-day (07:00 and 17:00 h), 1-week before RF (BR), the second week of RF (SWR), and the fourth week of RF (ER).Setting
For each session, subjects performed the YYIRT, and blood samples were taken before and 3-min after the test for biochemical measures.Participants
Fifteen soccer players.Main Outcome Measures
Total distance during the YYIRT, core temperature, body composition, dietary intakes, lipid (HDL-C, LDL-C, Apo-AI, B and Lp-a) and inflammatory (hs-CRP and Hcy) profiles.Results
Performances during the YYIRT were higher in the evening than the morning BR (P < 0.05), but this fluctuation was not observed during RF. Moreover, LDL-C, ApoB, and Lp-a were stable throughout the daytime BR. However, during RF, they decreased at 17:00 h (P < 0.05). Likewise, HDL-C and Apo-AI increased after the exercise and were higher at 17:00 h BR (P < 0.001). Moreover, these parameters increased during RF (P < 0.01). Furthermore, Hcy and hs-CRP increased during the exercise (P < 0.01) with higher evening levels BR. During ER, the diurnal pattern of Hcy was inversed (P < 0.001).Conclusions
This study concluded that caloric restriction induced by RF seems to ameliorate lipid and inflammatory markers of cardiovascular health during intermittent exercise performed in the evening. 相似文献16.
Alejandro Arenas-Pinto Alan Winston Wolfgang St?hr John Day Rebecca Wiggins Say Pheng Quah Jonathan Ainsworth Sue Fleck David Dunn Alex Accoroni Nicholas I. Paton for the PIVOT Trial Team 《PloS one》2014,9(7)
Objective
To compare two definitions of neurocognitive impairment (NCI) in a large clinical trial of effectively-treated HIV-infected adults at baseline.Methods
Hopkins Verbal Learning test-Revised (HVLT-R), Colour Trail (CTT) and Grooved Pegboard (GPT) tests were applied exploring five cognitive domains. Raw scores were transformed into Z-scores and NCI defined as summary NPZ-5 score one standard deviation below the mean of the normative dataset (i.e. <−1SD) or Z-scores <−1SD in at least two individual domains (categorical scale). Principal component analysis (PCA) was performed to explore the contribution of individual tests to the total variance.Results
Mean NPZ-5 score was −0.72 (SD 0.98) and 178/548 (32%) participants had NPZ-5 scores <−1SD. When impairment was defined as <−1SD in at least two individual tests, 283 (52%) patients were impaired. Strong correlations between the two components of the HVLT-R test (learning/recall) (r = 0.73), and the CTT and (attention/executive functioning) (r = 0.66) were observed. PCA showed a clustering with three components accounting for 88% of the total variance. When patients who scored <−1SD only in two correlated tests were considered as not impaired, prevalence of NCI was 43%. When correlated test scores were averaged, 36% of participants had NPZ-3 scores <−1SD and 32% underperformed in at least two individual tests.Conclusion
Controlling for differential contribution of individual test-scores on the overall performance and the level of correlation between components of the test battery used appear to be important when testing cognitive function. These two factors are likely to affect both summary scores and categorical scales in defining cognitive impairment.Trial registration
EUDRACT: 2007-006448-23 and ISRCTN04857074. 相似文献17.
Angeliki?Balasopoulou Biljana?Stankovi? Angeliki?Panagiotara Gordana?Nik?evic Brock?A.?Peters Anne?John Effrosyni?Mendrinou Apostolos?Stratopoulos Aigli?Ioanna?Legaki Vasiliki?Stathakopoulou Aristoniki?Tsolia Nikolaos?Govaris Sofia?Govari Zoi?Zagoriti Konstantinos?Poulas Maria?Kanariou Nikki?Constantinidou Maro?Krini Kleopatra?Spanou Nedeljko?Radlovic Bassam?R.?Ali Joseph?Borg Radoje?Drmanac George?Chrousos Sonja?Pavlovic Eleftheria?Roma Branka?Zukic George?P.?Patrinos Theodora?Katsila
Background
Celiac disease is a complex chronic immune-mediated disorder of the small intestine. Today, the pathobiology of the disease is unclear, perplexing differential diagnosis, patient stratification, and decision-making in the clinic.Methods
Herein, we adopted a next-generation sequencing approach in a celiac disease trio of Greek descent to identify all genomic variants with the potential of celiac disease predisposition.Results
Analysis revealed six genomic variants of prime interest: SLC9A4 c.1919G>A, KIAA1109 c.2933T>C and c.4268_4269delCCinsTA, HoxB6 c.668C>A, HoxD12 c.418G>A, and NCK2 c.745_746delAAinsG, from which NCK2 c.745_746delAAinsG is novel. Data validation in pediatric celiac disease patients of Greek (n?=?109) and Serbian (n?=?73) descent and their healthy counterparts (n?=?111 and n?=?32, respectively) indicated that HoxD12 c.418G>A is more prevalent in celiac disease patients in the Serbian population (P?<?0.01), while NCK2 c.745_746delAAinsG is less prevalent in celiac disease patients rather than healthy individuals of Greek descent (P?=?0.03). SLC9A4 c.1919G>A and KIAA1109 c.2933T>C and c.4268_4269delCCinsTA were more abundant in patients; nevertheless, they failed to show statistical significance.Conclusions
The next-generation sequencing-based family genomics approach described herein may serve as a paradigm towards the identification of novel functional variants with the aim of understanding complex disease pathobiology.18.
Background
In genetics it is customary to refer to double-stranded DNA as containing a "Watson strand" and a "Crick strand." However, there seems to be no consensus in the literature on the exact meaning of these two terms, and the many usages contradict one another as well as the original definition. Here, we review the history of the terminology and suggest retaining a single sense that is currently the most useful and consistent. 相似文献19.
Background
Copines are soluble, calcium-dependent membrane binding proteins found in a variety of organisms. Copines are characterized as having two C2 domains at the N-terminal region followed by an "A domain" at the C-terminal region. The "A domain" is similar in sequence to the von Willebrand A (VWA) domain found in integrins. The presence of C2 domains suggests that copines may be involved in cell signaling and/or membrane trafficking pathways. 相似文献20.
Michelle Sholzberg Tara Gomes David N. Juurlink Zhan Yao Muhammad M. Mamdani Andreas Laupacis 《PloS one》2016,11(2)