Stalk lodging, which is generally determined by stalk strength, results in considerable yield loss and has become a primary threat to maize (Zea mays) yield under high-density planting. However, the molecular genetic basis of maize stalk strength remains unclear, and improvement methods remain inefficient. Here, we combined map-based cloning and association mapping and identified the gene stiff1 underlying a major quantitative trait locus for stalk strength in maize. A 27.2-kb transposable element insertion was present in the promoter of the stiff1 gene, which encodes an F-box domain protein. This transposable element insertion repressed the transcription of stiff1, leading to the increased cellulose and lignin contents in the cell wall and consequently greater stalk strength. Furthermore, a precisely edited allele of stiff1 generated through the CRISPR/Cas9 system resulted in plants with a stronger stalk than the unedited control. Nucleotide diversity analysis revealed that the promoter of stiff1 was under strong selection in the maize stiff-stalk group. Our cloning of stiff1 reveals a case in which a transposable element played an important role in maize improvement. The identification of stiff1 and our edited stiff1 allele pave the way for efficient improvement of maize stalk strength.

• MeSH
• alely MeSH
• buněčná stěna metabolismus   MeSH
• CRISPR-Cas systémy MeSH
• fenotyp MeSH
• kukuřice setá genetika   MeSH
• lignin metabolismus   MeSH
• lokus kvantitativního znaku MeSH
• mapování chromozomů MeSH
• promotorové oblasti (genetika) * MeSH
• rostlinné geny MeSH
• rostlinné proteiny genetika   metabolismus   MeSH
• sekvenční analýza MeSH
• transformace genetická MeSH
• transpozibilní elementy DNA genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The aim of our study was to define mutations causing familial hypercholesterolemia (FH) phenotype in Czech hypercholesterolemic individuals. A combination of heteroduplex analysis, SSCP, DGGE, DNA sequencing and PCR/restriction analysis was used for this purpose. Molecular searching in the promoter region and coding sequence of the low density lipoprotein receptor (LDLR) gene in 130 patients from 68 unrelated families resulted in the identification of 37 sequence variations. Thirty of them are most likely disease causing mutations. Nineteen mutations were novel (two nonsense, five missense, six nucleotide(s) insertions and six nucleotide(s) deletions). Their pathological effect can be predicted on the basis of their position with respect to previously reported mutations with an estimated reduction of the receptor activity and/or premature termination of translation. These results expand our knowledge of mutations responsible for FH. Seven nucleotide variations were characterized as silent polymorphisms.

• MeSH
• cholesterol krev   MeSH
• DNA krev   genetika   MeSH
• dospělí MeSH
• heteroduplexní analýza MeSH
• hyperlipoproteinemie typ II krev   epidemiologie   genetika   MeSH
• LDL-receptory genetika   MeSH
• leukocyty chemie   MeSH
• lidé MeSH
• mutace genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• upravené články MeSH
• Geografické názvy
• Česká republika MeSH

We have examined the insertion of carbenes carrying leaving groups into the [nido-B11H13]2- dianion to form the [closo-1-CB11H12]- anion. The best procedure uses CF3SiMe3 and LiCl as the source of CF2. It is simple, convenient and scalable and proceeds with 70-90% yield. Density functional calculations have been used to develop a mechanistic proposal that accounts for the different behavior of CF2, requiring only one equivalent of base for successful conversion of Na[nido-B11H14]- to [closo-1-CB11H12]-, and CCl2 and CBr2, which require more.

• MeSH
• chlorid lithný chemie   MeSH
• fluorované uhlovodíky chemická syntéza   chemie   MeSH
• molekulární struktura MeSH
• sloučeniny boru chemie   MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND AND AIMS: Stomatal density (SD) generally decreases with rising atmospheric CO2 concentration, Ca. However, SD is also affected by light, air humidity and drought, all under systemic signalling from older leaves. This makes our understanding of how Ca controls SD incomplete. This study tested the hypotheses that SD is affected by the internal CO2 concentration of the leaf, Ci, rather than Ca, and that cotyledons, as the first plant assimilation organs, lack the systemic signal. METHODS: Sunflower (Helianthus annuus), beech (Fagus sylvatica), arabidopsis (Arabidopsis thaliana) and garden cress (Lepidium sativum) were grown under contrasting environmental conditions that affected Ci while Ca was kept constant. The SD, pavement cell density (PCD) and stomatal index (SI) responses to Ci in cotyledons and the first leaves of garden cress were compared. (13)C abundance (δ(13)C) in leaf dry matter was used to estimate the effective Ci during leaf development. The SD was estimated from leaf imprints. KEY RESULTS: SD correlated negatively with Ci in leaves of all four species and under three different treatments (irradiance, abscisic acid and osmotic stress). PCD in arabidopsis and garden cress responded similarly, so that SI was largely unaffected. However, SD and PCD of cotyledons were insensitive to Ci, indicating an essential role for systemic signalling. CONCLUSIONS: It is proposed that Ci or a Ci-linked factor plays an important role in modulating SD and PCD during epidermis development and leaf expansion. The absence of a Ci-SD relationship in the cotyledons of garden cress indicates the key role of lower-insertion CO2 assimilation organs in signal perception and its long-distance transport.

• MeSH
• Arabidopsis cytologie   účinky léků   MeSH
• buk (rod) cytologie   účinky léků   MeSH
• dehydratace MeSH
• Helianthus cytologie   účinky léků   MeSH
• kotyledon účinky léků   fyziologie   MeSH
• Lepidium cytologie   účinky léků   MeSH
• oxid uhličitý farmakologie   MeSH
• počet buněk MeSH
• průduchy rostlin cytologie   účinky léků   MeSH
• životní prostředí MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Endothelial dysfunction is an early manifestation of cardiovascular disease (CVD) and consistently observed in patients with chronic kidney disease (CKD). We hypothesized that CKD is associated with systemic damage to the microcirculation, preceding macrovascular pathology. To assess the degree of "uremic microangiopathy", we have measured microvascular density in biopsies of the omentum of children with CKD. PATIENTS AND METHODS: Omental tissue was collected from 32 healthy children (0-18 years) undergoing elective abdominal surgery and from 23 age-matched cases with stage 5 CKD at the time of catheter insertion for initiation of peritoneal dialysis. Biopsies were analyzed by independent observers using either a manual or an automated imaging system for the assessment of microvascular density. Quantitative immunohistochemistry was performed for markers of autophagy and apoptosis, and for the abundance of the angiogenesis-regulating proteins VEGF-A, VEGF-R2, Angpt1 and Angpt2. RESULTS: Microvascular density was significantly reduced in uremic children compared to healthy controls, both by manual imaging with a digital microscope (median surface area 0.61% vs. 0.95%, p<0.0021 and by automated quantification (total microvascular surface area 0.89% vs. 1.17% p = 0.01). Density measured by manual imaging was significantly associated with age, height, weight and body surface area in CKD patients and healthy controls. In multivariate analysis, age and serum creatinine level were the only independent, significant predictors of microvascular density (r2 = 0.73). There was no immunohistochemical evidence for apoptosis or autophagy. Quantitative staining showed similar expression levels of the angiogenesis regulators VEGF-A, VEGF-receptor 2 and Angpt1 (p = 0.11), but Angpt2 was significantly lower in CKD children (p = 0.01). CONCLUSIONS: Microvascular density is profoundly reduced in omental biopsies of children with stage 5 CKD and associated with diminished Angpt2 signaling. Microvascular rarefaction could be an early systemic manifestation of CKD-induced cardiovascular disease.

• MeSH
• angiopoetin-1 krev   MeSH
• angiopoetin-2 krev   MeSH
• apoptóza genetika   MeSH
• autofagie genetika   MeSH
• biologické markery krev   MeSH
• biopsie MeSH
• chronická renální insuficience krev   genetika   patologie   MeSH
• dítě MeSH
• kardiovaskulární nemoci krev   genetika   patologie   MeSH
• kojenec MeSH
• lidé MeSH
• mikrocévy patologie   MeSH
• mikrocirkulace genetika   MeSH
• mladiství MeSH
• novorozenec MeSH
• peritoneální dialýza MeSH
• předškolní dítě MeSH
• receptor 2 pro vaskulární endoteliální růstový faktor krev   MeSH
• regulace genové exprese MeSH
• vaskulární endoteliální růstový faktor A krev   MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Clubfoot deformity (pes equinovarus) is one of the most common birth defects, and its etiology is still unknown. Initial clubfoot treatment is based on the Ponseti method throughout most of the world. Despite the effectiveness of this therapy, clubfoot may relapse. Recent studies confirm the theory of active fibrotic remodeling processes in the extracellular matrix of the affected tissue. The aim of this study was to clarify whether relapses in clubfoot therapy are associated with altered angiogenesis and to suggest possible regulatory pathways of this pathologic process. METHODS: We compared microvessel density, arteriole density, and concentration of angioproliferative-related proteins found between tissues in the contracted, that is, the medial side (M-side), and noncontracted, that is, the lateral side (L-side) of the relapsed clubfeet. Tissue samples from 10 patients were analyzed. Histopathologic analysis consisted of immunohistochemistry and image analysis. Real-time polymerase chain reaction was used to study mRNA expression. RESULTS: An increase in microvessel and arteriole density was noted in contracted, relapsed clubfoot tissue. This was accompanied by a significant increase in the levels of the vascular endothelial growth factor, vascular endothelial growth factor receptor 2, β catenin and active β catenin. Vascular endothelial growth factor, vascular endothelial growth factor receptor 2, and CD31 overexpression was also seen with mRNA analysis. CONCLUSIONS: Increased microvessel and arteriole density in the contracted side of the relapsed clubfoot was noted. These processes are mediated by specific proangiogenic proteins that are overexpressed in the contracted tissue. These findings contribute to the etiology and the development of relapses in the treatment of clubfoot. LEVEL OF EVIDENCE: Level II-analytical and prospective.

• MeSH
• arterioly * MeSH
• beta-katenin metabolismus   MeSH
• lidé MeSH
• patologická angiogeneze * MeSH
• pes equinovarus etiologie   metabolismus   terapie   MeSH
• předškolní dítě MeSH
• prospektivní studie MeSH
• receptor 2 pro vaskulární endoteliální růstový faktor metabolismus   MeSH
• recidiva MeSH
• sádrové obvazy MeSH
• vaskulární endoteliální růstový faktor A metabolismus   MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Sequence dependence of (13) C and (15) N chemical shifts in the receiver domain of CKI1 protein from Arabidopsis thaliana, CKI1RD , and its complexed form, CKI1RD •Mg(2+), was studied by means of MD/DFT calculations. MD simulations of a 20-ns production run length were performed. Nine explicitly hydrated structures of increasing complexity were explored, up to a 40-amino-acid structure. The size of the model necessary depended on the type of nucleus, the type of amino acid and its sequence neighbors, other spatially close amino acids, and the orientation of amino acid NH groups and their surface/interior position. Using models covering a 10 and a 15 Å environment of Mg(2+), a semi-quantitative agreement has been obtained between experiment and theory for the V67-I73 sequence. The influence of Mg(2+) binding was described better by the 15 Å as compared to the 10 Å model. Thirteen chemical shifts were analyzed in terms of the effect of Mg(2+) insertion and geometry preparation. The effect of geometry was significant and opposite in sign to the effect of Mg(2+) binding. The strongest individual effects were found for (15) N of D70, S74, and V68, where the electrostatics dominated; for (13) Cβ of D69 and (15) N of K76, where the influences were equal, and for (13) Cα of F72 and (13) Cβ of K76, where the geometry adjustment dominated. A partial correlation between dominant geometry influence and torsion angle shifts upon the coordination has been observed.

• MeSH
• hořčík chemie   MeSH
• izotopy dusíku chemie   MeSH
• izotopy uhlíku chemie   MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• proteinkinasy chemie   MeSH
• proteinové domény MeSH
• proteiny huseníčku chemie   MeSH
• simulace molekulární dynamiky MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

To compare the anchorage strength of Socon CS cannulated pedicle screws (B. Braun, Aesculap) with that of Socon screws in human cadaver vertebrae, using pull-out strength testing. MATERIAL Twelve samples involving T12 to L3 vertebrae were prepared and a total of 20 pedicle screws, 10 Socon CS and 10 Socon screws, were inserted in them. All screws were 55 mm in length and 6 mm in diameter. After placement, Socon CS pedicle screws were augmented with bone cement (Cimplant cement application kit, B. Braun, Aesculap). METHODS Both Socon CS and Socon screws were subjected to monotonous loading in the testing device ZWICK Z 020-TND with tensile stress applied in the screw axis. We evaluated the magnitude of strength resulting in screw loosening and the relationship between this strength and bone density of the sample. RESULTS Bone density of measured samples corresponded either to osteopenia, i.e. T-score range of -1 to -2.5 SD (standard deviation) or osteoporosis, i.e. T-score -2.5 SD. The average bone density of all samples corresponded to a T-score of -3.1 SD. Bone-screw linkage was found to be associated with both bone-cement and screw-cement interface. Pull-out strength was significantly higher for the Socon CS than the Socon screws (t-test, p<0.0005). In the Socon screws, the linear correlation between pull-out strength and bone density was significant at a 5% level of statistical significance (p=0.008) while, in the Socon CS screws, it was not significant (p=0.065). DISCUSSION The poor quality of osteoporotic bone is responsible for a higher frequency of implant failure due to loosening, particularly when implants developed for healthy bone are used. In this biomechanical study, we tested one of the possibilities of how to reduce the risk of implant failure by pedicle screw augmentation with bone cement. CONCLUSIONS The results of this study confirm the hypothesis that the anchorage of Socon CS cannulated pedicle screws with bone cement augmentation is disrupted by significantly higher pull-out strength than that of Socon screws, when subjected to monotonous loading. However, more clinical studies are needed to evaluate clinical outcomes

• MeSH
• bederní obratle chirurgie   patofyziologie   zranění   MeSH
• biomechanika MeSH
• fraktury páteře chirurgie   patofyziologie   MeSH
• hrudní obratle chirurgie   patofyziologie   zranění   MeSH
• kostní denzita MeSH
• kostní šrouby MeSH
• lidé MeSH
• mrtvola MeSH
• osteoporotické fraktury chirurgie   patofyziologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• techniky in vitro MeSH
• Check Tag
• lidé MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• srovnávací studie MeSH

Kotevní miniimplantáty patří do skupiny dočasných kotevních zařízení. K jejich velké oblibě a rozšíření vedla zejména snadnost zavádění a variabilita využití. Používají se k redukci recipročního působení ortodontického aparátu a poskytují tak ízv. absolutní kotvení. Zavádějí se podle plánovaného využití do kosti alveolárního výběžku, často mezi kořeny zubů z vestibulární nebo palatinální strany a dále do oblasti patrového švu. K jejich úspěšnému zavedení je potřeba dostatečné široký prostor mezi kořeny zubů. Kritériem úspěšnosti je poté jejich pevnost a odolnost k ortodontickým silám. Primární stabilita, tedy pevnost minišroubu bezprostředně po jeho zavedení, je základním faktorem úspěšnosti a je pro jeho klinické použtí velkou výhodou, neboť minišroub lze díky tomu okamžitě ortodonticky zatížit. Cílem tohoto referátu bylo shrnout problematiku minišroubu. Zejména pak jejich vývoje, definice a rozdělení. Dále pak shrnout informace o primární stabilitě minišroubu a faktorech které ji ovlivňují.

Anchorage miniimplants, belonging to the group of temporary anchorage devices, became very popular thanks to easy manipulation and a wide variety of applications. They are used to eliminate reciprocal effect of orthodontic appliance, and thus they provide the so-called absolute anchorage. According to the treatment plan, they are inserted into alveolar process, between dental roots from vestibular or palatal side, and into the area of palatal suture. For successful insertion of a miniimplant, enough space between dental roots is required. Successful function is given by their solidity and resistance to orthodontic forces. Primary stability, i.e. the solidity of a miniscrew immediately after its insertion, is the principal factor ofsuccessful application, and it is a great advantage in clinical practice because the miniscrew may be immediately loaded. The aim of the work is to give a survey of miniscrews, their development, definition and categories. We also bring information on primary stability of miniscrews, and of factors contributing to it.

• Klíčová slova
• miniimplantáty, minišrouby, osseointegrace,
• MeSH
• biokompatibilní materiály MeSH
• distorze a distenze prevence a kontrola   MeSH
• kostní denzita MeSH
• kostní šrouby * klasifikace   využití   MeSH
• lidé MeSH
• miniaturizace MeSH
• osteointegrace fyziologie   MeSH
• postupy ortodontického kotvení dějiny   MeSH
• protézy - design MeSH
• retence zubní protézy metody   MeSH
• zubní implantáty * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

IMPORTANCE: Posterior polymorphous corneal dystrophy (PPCD) is a very rare disorder characterized by primary changes of the posterior corneal layers. Sequence variants in 3 genes are associated with the development of PPCD, including ZEB1 that is responsible for PPCD3. Evidence suggests at least 1 more gene remains to be identified. OBJECTIVE: To determine the molecular genetic cause of PPCD3. DESIGN: We performed extensive ophthalmological examination, including rotating Scheimpflug imaging technology and specular microscopy, and direct sequencing of the ZEB1 coding region. Comprehensive review of published PPCD3-causing variants was undertaken. SETTING: Ophthalmology department of a university hospital. PARTICIPANTS: Four Czech probands. MAIN OUTCOMES AND MEASURES: Results of ophthalmological examination and direct sequencing of the ZEB1 coding region. RESULTS: The following 2 novel frameshift mutations within ZEB1 were identified: c.2617dup in exon 8 in a 22-year-old woman, considered to be most likely de novo in origin, and c.698dup in exon 6 in a 20-year-old man. The first patient had mild changes consistent with PPCD and bilateral best-corrected visual acuity of 1.00. The corneal phenotype of the patient in the second case was more severe, with best-corrected visual acuity of 0.40 OD and 0.05 OS. Corneas of both probands were abnormally steep (keratometry readings, flat ≥ 47.4 diopters [D] and steep ≥ 49.2 D) with increased pachymetry values but no pattern indicative of keratoconus. Specular microscopy in both patients revealed reduced endothelial cell density (range, 1055/mm² to 1655/mm²). Both probands had a history of surgery for inguinal hernia; the male patient also reported hydrocele. CONCLUSIONS AND RELEVANCE: Nucleotide changes within the coding region of ZEB1 underlie the pathogenesis of PPCD in 4 of 23 Czech probands (17%). The cumulative de novo ZEB1 mutation rate is at least 14%. Possible involvement of ZEB1 sequence variants not readily identified by direct sequencing of coding regions needs to be further investigated. Our findings also have implications for patient counseling.

• MeSH
• dědičné dystrofie rohovky diagnóza   genetika   MeSH
• exony genetika   MeSH
• fenotyp MeSH
• homeodoménové proteiny genetika   MeSH
• lidé MeSH
• mladý dospělý MeSH
• molekulární biologie MeSH
• nitrooční tlak MeSH
• pachymetrie rohovky MeSH
• počet buněk MeSH
• polymerázová řetězová reakce MeSH
• posunová mutace * MeSH
• rohovková topografie MeSH
• rohovkový endotel patologie   MeSH
• transkripční faktory genetika   MeSH
• úbytek endoteliálních buněk rohovky genetika   MeSH
• zraková ostrost MeSH
• Check Tag
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH