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1.
Anat Histol Embryol ; 53(4): e13070, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39031825

RESUMO

This paper presents the conclusions of a comparative analysis of six osteological features: the Structure of the vertebral column, the morphology of the predorsal bones, the vertebral column regionalization, the pterygiophore interdigitation with neural spines of dorsal fin, the pterygiophores interdigitation of with the haemal spines of the anal fin, and the intermuscular bones (IMB) and hypomerals (HM) of 12 clupeid species of the families Alosidae, Dorosomatidae, Dussumieridae and Ehiravidae. Conceivable taxonomically beneficial osteological features are nominated and utilized to discrete the clupeid species explored. Formulae for the structure of the vertebral column, the dorsal- and anal-fin pterygiophores' interdigitation with the neural and haemal spines of the vertebrae are established. These morphological descriptive traits disclose a morphotype that may be related to the mode of swimming of the species searched. The morphological study of the vertebral column of the species in question permits the division of this bony structure into six morphologically different regions. This regionalization is more intricate than the classical division in abdominal and caudal parts only.


Assuntos
Coluna Vertebral , Animais , Irã (Geográfico) , Coluna Vertebral/anatomia & histologia , Peixes/anatomia & histologia , Peixes/classificação , Nadadeiras de Animais/anatomia & histologia , Osso e Ossos/anatomia & histologia
2.
Technol Cancer Res Treat ; 23: 15330338231225864, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38311933

RESUMO

Purpose: This study aims to develop a data-collecting package ExpressMLC and investigate the applicability of MapCHECK2 for multileaf collimator (MLC) modeling and commissioning for complex radiation treatment plans. Materials and methods: The MLC model incorporates realistic parameters to account for sophisticated MLC features. A set of 8 single-beam plans, denoted by ExpressMLC, is created for the determination of parameters. For the commissioning of the MLC model, 4 intensity modulated radiation therapy (IMRT) plans specified by the AAPM TG 119 report were transferred to a computed tomography study of MapCHECK2, recalculated, and compared to measurements on a Varian accelerator. Both per-beam and composite-beam dose verification were conducted. Results: Through sufficient characterization of the MLC model, under 3%/2 mm and 2%/2 mm criteria, MapCHECK2 can be used to accurately verify per beam dose with gamma passing rate better than 90.9% and 89.3%, respectively, while the Gafchromic EBT3 films can achieve gamma passing rate better than 89.3% and 85.7%, respectively. Under the same criteria, MapCHECK2 can achieve composite beam dose verification with a gamma passing rate better than 95.9% and 90.3%, while the Gafchromic EBT3 films can achieve a gamma passing rate better than 96.1% and 91.8%; the p-value from the Mann Whitney test between gamma passing rates of the per beam dose verification using full MapCHECK2 package calibrated MLC model and film calibrated MLC model is .44 and .47, respectively; the p-value between those of the true composite beam dose verification is .62 and .36, respectively. Conclusion: It is confirmed that the 2-dimensional (2D) diode array MapCHECK2 can be used for data collection for MLC modeling with the combination of the ExpressMLC package of plans, whose doses are sufficient for the determination of MLC parameters. It could be a fitting alternative to films to boost the efficiency of MLC modeling and commissioning without sacrificing accuracy.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Imagens de Fantasmas , Raios gama , Radioterapia de Intensidade Modulada/métodos , Radiometria/métodos
3.
Drug Dev Ind Pharm ; 50(2): 124-134, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158799

RESUMO

OBJECTIVE: This research work aimed to form vesosomes using combination of two drugs ergotamine (ERG) and caffeine for synergistic activity when given intranasally resulting in faster absorption, steric stability, and controlled release. SIGNIFICANCE: The multicompartment vesicles viz., vesosomes of ERG tartrate proved to increase absorption of drugs post-intranasal administration, bypassing the blood-brain barrier via the olfactory pathway. METHODS: The phospholipids like soya lecithin, cholesterol, and dipalmitoyl phosphatidylcholine (DPPC) were used to form a multicompartment structure called vesosomes using ethanol-induced interdigitation of lipids as the preparation method. RESULTS: The formulation showed low particle size (PS) of 315.48 ± 14.27 nm with zeta potential (ZP) of -21.78 ± 4.72 mV, higher % EE of 91.13 ± 1.29%, and controlled release kinetics, when assessed for in-vitro and ex-vivo studies as 97.64 ± 5.13% and 82.25 ± 3.27% release, respectively. Vesosomes displayed several advantages over liposomes like improved stability against phospholipase-induced enzymatic degradation and higher brain uptake 3.41-fold increase of ERG via the olfactory pathway. CONCLUSIONS: The stable vesosomes prepared using interdigitation of saturated phospholipids proved to be a viable option for ERG when administered intranasally for better absorption and bioavailability coupled with ease of administration gaining wider patient acceptance.


Vesosomes as multicompartment vesicles formulated of ergotamine (ERG) and caffeine for synergistic action in migraine treatment.Ethanol induced for interdigitation of lipids in vesosomes preparation exhibited nano-size, good colloidal stability, better encapsulation efficiency, and controlled release profile.ERG vesosomes demonstrated stability against phospholipase-induced enzymatic degradation.


Assuntos
Cafeína , Ergotamina , Humanos , Administração Intranasal , Preparações de Ação Retardada , Lipossomos/química , Tamanho da Partícula , Fosfolipídeos
4.
Asian Pac J Cancer Prev ; 24(10): 3441-3445, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37898849

RESUMO

BACKGROUND: In cervical cancer treatment, overall treatment time (OTT) is an important prognostic factor. This study compares the clinical outcomes when High-Dose-Rate Intracavitary-Brachytherapy(HDR-ICRT) is interdigitated with external beam radiotherapy(EBRT) versus sequential HDR-ICRT after EBRT in the treatment of locally advanced carcinoma cervix. METHODS: Histologically confirmed carcinoma cervix patients [FIGO Stage IIB-IVA (except IIIC-2)] were included and randomized into two groups. The study group received EBRT 50Gy in 25 fractions with interdigitated HDR-ICRT 7Gy per fraction weekly for three fractions starting after completion of 3 weeks of EBRT or as soon as cervical os became negotiable thereafter. Patients in the control group received EBRT 50Gy in 25 fractions with sequential HDR-ICRT 7Gy per fraction weekly for three fractions starting one week after completion of EBRT. All patients were regularly followed up during and after radiotherapy for local toxicity and disease control. RESULTS: This study enrolled 102 patients; 51 in each arm. Median OTT in study and control arm were 46 and 60 days, respectively. Median follow-up duration was 24 months (two years). Loco-regional control after two years of follow-up was 84.31 % and 72.54% of patients in study arm control arm respectively (p-value 0.148). Two (3.92%) patients from study arm and eight (15.68%) from control arm had residual disease. Two patients in study arm and one from control arm had local recurrence. Two patients from study arm three patients from control arm developed distant metastases. RTOG mucosal grade III acute mucosal toxicity in either arm. Cervical-os negotiability was limiting factor for interdigitated HDR-ICRT. CONCLUSIONS: Interdigitated HDR-ICRT with EBRT may give local control with manageable toxicities as compared to sequential HDR-ICRT, with the advantage of significant reduction in OTT.
.


Assuntos
Braquiterapia , Carcinoma de Células Escamosas , Neoplasias do Colo do Útero , Feminino , Humanos , Colo do Útero/patologia , Carcinoma de Células Escamosas/patologia , Dosagem Radioterapêutica , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/patologia
5.
Bone Rep ; 19: 101714, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37767331

RESUMO

Objective: Differences in complexity of cranial suture forms on the endocranial (i.e., deep) and ectocranial (i.e., superficial) skull surfaces have been noted in the literature, indicating through thickness three-dimensional (3D) suture variability depending on the chosen section and necessity for considering the complete 3D structure in many cases. This study aims to evaluate the variability of suture morphology through the skull thickness using a rat model, and to provide more robust metrics and methodologies to analyze suture morphology. Design: X-ray micro-computed tomographic (µCT) imaging methods were utilized in order to provide internal structure information. Methods were developed to isolate and analyze sutures widths and linear interdigitation index (LII) values on each adjacent offset transverse plane of the µCT datasets. LII was defined as the curved path length of the suture divided by the linear length between the ends of the region of interest. Scans were obtained on 15 female rats at ages of 16, 20, and 24 weeks (n = 5/age). Samples were imaged at 18 µm resolutions with 90 kV source voltage, 278 µA source amperage, and 0.7° increments. Suture widths and LII values were compared using a Kruskal-Wallis test. Results: 3D variability in local suture widths within individuals, as well as through thickness variabilities in planar widths and LII was observed. Kruskal-Wallis tests for bulk through thickness averaged suture widths and LII were found to be statistically insignificant, despite clear geometric differences through suture thicknesses. Conclusion: Although the bulk morphometric variability between age groups was found to be statistically insignificant, the 3D variability within individuals point to the importance of analyzing suture form using 3D metrics when studying suture development, response to functional activity, or morphometry in general.

6.
J Biomol Struct Dyn ; : 1-8, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656194

RESUMO

Water permeation through phospholipid/cholesterol bilayers is the key to understanding tension-induced rupture of biological cell membranes. We performed molecular dynamics simulations of stretched phospholipid/cholesterol bilayers to investigate changes in the free energy profile of water molecules across the bilayer and the lipid structure responsible for water permeation. We modeled stretching of the bilayer by applying areal strain. In stretched phospholipid/cholesterol bilayers, the hydrophobic tail of the phospholipids became disordered and the free energy barrier to water permeation decreased. Upon exceeding the critical areal strain, a phase transition to an interdigitated gel phase occurred before rupture, and the hydrophobic tail ordering as well as the free energy barrier were restored. In pure phospholipid bilayers, we did not observe such recoveries. These transient recoveries in the phospholipid/cholesterol bilayer suppressed water permeation and membrane rupture, followed by an increase in the critical areal strain at which the bilayer ruptured. This result agrees with experimental results and provides a reasonable molecular mechanism for the toughness of phospholipid/cholesterol bilayers under tension.Communicated by Ramaswamy H. Sarma.

7.
Curr Eye Res ; 48(11): 1050-1056, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37539829

RESUMO

PURPOSE: Photoreceptor (PR) outer segments, retinal pigment epithelium apical processes, and inter-PR matrix contribute to the interdigitation zone (IZ) of optical coherence tomography (OCT). We hypothesize that this interface degrades over adulthood, in concert with a delay of rod mediated dark adaptation (RMDA). To explore this idea, we determined IZ discernibility and RMDA in younger and older adults. METHODS: For this cross-sectional study, eyes of 20 young (20-30 years) and 40 older (≥60 years) participants with normal maculas according to the AREDS 9-step grading system underwent OCT imaging and RMDA testing at 5° superior to the fovea. Custom FIJI plugins enabled analysis for IZ discernibility at 9 eccentricities in 0.5 mm steps on one single horizontal B-scan through the fovea. Locations with discernible IZ met two criteria: visibility on B-scans and a distinct peak on a longitudinal reflectivity profile. The frequency of sites meeting both criteria was compared between both age groups and correlated with rod intercept time (RIT). RESULTS: The median number of locations with discernible IZ was significantly higher (foveal, 4 vs. 0, p = 0.0099; extra-foveal 6 vs. 0, p < 0.001) in eyes of young (26 ± 3 years) compared to older (73 ± 5 years) participants. For the combined young and older sample, the higher frequency of discernible IZ was correlated with shorter RIT (faster dark adaptation) (rs = -0.56, p < 0.0001). This association was significant within young eyes (rs = -0.54; p = 0.0134) and not within older eyes (rs = -0.29, p = 0.706). CONCLUSIONS: Results suggest that the interface between outer segments and apical processes degrades in normal aging, potentially contributing to delayed rod-mediated dark adaptation. More research is needed to verify an age-related association between IZ discernibility and rod-mediated dark adaptation. If confirmed in a large sample, IZ discernibility might prove to be a valuable biomarker and predictor for visual function in aging.

8.
Res Sq ; 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37609321

RESUMO

Photoreceptors in the retina are specialized neuronal cells that perceive light and play a central role in the visual system. Damage to photoreceptors is a clinical feature often associated with various retinal degenerative disorders. The photoreceptor bed comprises a unique extracellular matrix (ECM) scaffold often described as the interphotoreceptor matrix (IPM) in the subretinal space, vital during retinal development and homeostasis. In this study, we used focused ion beam scanning electron microscopy (FIB-SEM) and transmission electron microscopy (TEM) to analyze the ultrastructural architecture of the retinal pigmented epithelium (RPE)-photoreceptor complex in mice. Additionally, we describe methods for retinal preparation in EM imaging. TEM images display ultrastructural retina layers, including Bruch's membrane and the interdigitation zone (IZ). The 3-dimensional reconstruction of the outer retina revealed individual photoreceptors, the connection between their inner and outer segment via the photoreceptor cilia, and photoreceptor interaction with the RPE ciliary processes. Our findings highlight the importance of FIB-SEM in deciphering the ultrastructural details of RPE-photoreceptor interactions in the IPM complex which are essential for the maintenance of retinal architecture.

9.
Injury ; 54(10): 110931, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37495450

RESUMO

INTRODUCTION: Concerning rates of nonunion in articular distal humerus fractures indicate an unsolved problem. The fixation principles of O'Driscoll describe linking the fractured articular segment to the distal humerus columns with compression screws which creates a stable fixed angle construct. A novel device has been introduced which utilizes an interlocking beam through the articular segment to connect the distal aspect of the medial and lateral plates, creating a linked construct. We sought to evaluate the stability of this linked construct using an articular model of distal humerus fracture. MATERIALS AND METHODS: Ten matched pair specimens of 65 years of age or older were randomized to the use (LB group) or non-use (NLB group) of an interlocking beam to link the medial and lateral locking plates in fixation of an AO Type C3 fracture model. Outside of the linking beam, fixation between the matched pairs was consistent using 2.7 mm locking screws distally with fixed trajectories and +/- 2 mm lengths. RESULTS: Mean stiffness was 273 Newtons/mm in the LB group and 225 Newtons/mm in the NLB group (p = 0.001). Mean maximum displacement was 0.28 in the LB group and 0.93 mm in the NLB group (p = 0.006). Mean load to failure was 277 pounds in the LB group and 280 pounds in the NLB group (p = 0.94). DISCUSSION: Our results indicate that an interlocking beam which links the medial and lateral plates provides greater stability compared to a similar construct without an interlocking beam. We attribute this finding to the beam's double supported design which resists cantilever bending and provides robust compression of the fractured fragments.


Assuntos
Fraturas Distais do Úmero , Fraturas Intra-Articulares , Humanos , Fenômenos Biomecânicos , Placas Ósseas , Fixação de Fratura , Fixação Interna de Fraturas/métodos , Úmero , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/cirurgia
10.
Methods Mol Biol ; 2664: 3-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37423978

RESUMO

The most distinctive characteristic of podocytes in the kidney is the presence of interdigitating cell processes with nephrin and podocin that are concentrated at sites of cell-cell contact. Unfortunately, these defining features are easily lost in culture. We previously reported culture conditions that can restore the differentiated phenotypes in primary cultures of rat podocyte. Since then, some of the materials used have been discontinued or improved. In this chapter, we therefore provide our most recent protocol for the restoration of the podocyte phenotype in culture.


Assuntos
Podócitos , Ratos , Animais , Glomérulos Renais , Rim , Fenótipo , Diferenciação Celular
11.
J World Fed Orthod ; 12(4): 141-149, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37400305

RESUMO

BACKGROUND: Sutures exist in the craniofacial area, and the pattern of maturation and synostosis of facial sutures is largely unknown. METHODS: For a comprehensive understanding of the three-dimensional circummaxillary suture micromorphology, human midpalatal suture (MPS) and pterygomaxillary articular complex from eight subjects' (five males, three females, 72-88 years old) autopsies were longitudinally scanned with microcomputed tomography. Additional histology was performed for hematoxylin and eosin staining. Sutural micromorphology was assessed by interdigitation index (II), obliteration index (OI) and obliteration number. Intergroup comparisons were performed with Kruskal-Wallis and Mann-Whitney U with Bonferroni correction (α = 0.005). Correlation with anteroposterior and craniocaudal gradients was assessed with Spearman's correlation test (α = 0.05). RESULTS: Maxillary region of MPS presented a higher II 1.50 (0.61) and obliteration number per slice 8 (9) (P < 0.005). OI was increased in palatomaxillary 35% (47%) followed by pterygopalatine suture 25% (49%) (P < 0.005). The II and OI of the MPS exhibited only a weak anteroposterior gradient, with relatively low correlations. Obliteration areas were found sporadically along the entire MPS. CONCLUSIONS: Based on these findings, it is conceivable that the success of nonsurgical maxillary expansion largely depends on individual variations in sutural morphology and maturation rather than appliance design.


Assuntos
Suturas Cranianas , Maxila , Masculino , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Microtomografia por Raio-X , Suturas Cranianas/diagnóstico por imagem , Maxila/diagnóstico por imagem , Procedimentos Neurocirúrgicos , Suturas
12.
Med Biol Eng Comput ; 61(9): 2367-2377, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37076651

RESUMO

The midpalatal suture (MPS) corresponds to the tissue that joins the two maxillary bones. Understanding the mechanical behavior of this tissue is of particular interest to those patients who require orthodontic treatments such as Rapid Maxillary Expansion (RME). The objective of this research was to observe the influence of interdigitation and collagen fibers on the mechanical response of MPS. To this end, a finite element analysis in two-dimensional models of the bone-suture-bone interface was performed considering the characteristics of the MPS. The geometry of the suture was modeled with 4 different levels of interdigitation: null, moderate, scalloped and fractal. The influence of collagen fibers, aligned transversely along the suture, was considered by incorporating linked structures of the bone fronts. According to the results, the factor that has the greatest impact on the magnitude and distribution of stresses is the interdigitation degree. A higher level of interdigitation produces an increase in tissue stiffness and a lower influence of collagen fibers on the mechanical response of the tissue. Therefore, this research contributes to the understanding of the MPS biomechanics by providing information that may be useful to health staff when evaluating the feasibility of procedures such as RME.


Assuntos
Suturas Cranianas , Maxila , Humanos , Análise de Elementos Finitos , Suturas , Colágeno
13.
Evol Dev ; 25(3): 209-225, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36896717

RESUMO

Lambeosaurine hadrosaurids exhibited extreme modifications to the skull, where the premaxillae, nasals, and prefrontals were modified to form their iconic supracranial crests. This morphology contrasts with their sister group, Hadrosaurinae, which possessed the plesiomorphic arrangement of bones. Although studies have discussed differences between lambeosaurine and hadrosaurine skull morphology and ontogeny, there is little information detailing suture modifications through ontogeny and evolution. Suture morphology is of particular interest due to its correlation with the mechanical loading of the skull in extant vertebrates. We quantify and contrast the morphology of calvarial sutures in iguanodontians and ontogenetic series of Corythosaurus and Gryposaurus to test whether the evolution of lambeosaurine crests impacted the mechanical loading of the skull. We found that suture interdigitation (SI) increases through ontogeny in hadrosaurids, although this increase is more extreme in Corythosaurus than Gryposaurus, and overall suture complexity (i.e., overall shape) remained constant. Lambeosaurines also have higher SI than other iguanodontians, even in crestless juveniles, suggesting that increased sinuosity is unrelated to the structural support of the crest. Hadrosaurines and basal iguanodontians did not differ. Similarly, lambeosaurines have more complexly shaped sutures than hadrosaurines and basal iguanodontians, while the latter two groups do not differ. Taken together, these results suggest that lambeosaurine calvarial sutures are more interdigitated than other iguanodontians, and although suture sinuosity increased through ontogeny, the suture shape remained constant. These ontogenetic and evolutionary patterns suggest that increased suture complexity in lambeosaurines coincided with crest evolution, and corresponding modifications to their facial skeleton altered the distribution of stress while feeding.


Assuntos
Dinossauros , Crânio , Animais , Crânio/anatomia & histologia , Cabeça , Dinossauros/anatomia & histologia , Suturas
14.
BMC Ophthalmol ; 23(1): 100, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918830

RESUMO

BACKGROUND: The study aims to investigate the relationship between the volume-accumulated reflectivity (termed "integral") on spectral domain optical coherence tomography (SD-OCT) and cone density on adaptive optics (AO) imaging. METHODS: In this cross-sectional study, both eyes of 32 healthy subjects and 5 patients with inherited retinal diseases (IRD) were studied. The parameter, integral, was defined as the volume-accumulated reflectivity values in a selected region on OCT images; integrals of the ellipsoid zone (EZ) and interdigitation zone (IZ) were measured at 2°, 3°, 4°, 5°and 6° eccentricity along the four meridians on fovea-centered OCT B-scans. Cone density in the same region was measured using a flood illumination adaptive optics camera RTX1. RESULTS: Integrals of EZ, IZ and cone density shared similar distribution patterns. Integral of the IZ was better correlated with cone density in both healthy people (r = 0.968, p < 0.001) and those with IRD (r = 0.823, p < 0.001) than direct measurements of reflectivity on OCT images. A strong correlation was found between best corrected visual acuity (BCVA) and cone density at 2° eccentricity (r = -0.857, p = 0.002). BCVA was also correlated with the integral of the IZ at the foveola (r = -0.746, p = 0.013) and fovea (r = -0.822, p = 0.004). CONCLUSIONS: The new parameter "integral" of the photoreceptor outer segment measured from SD-OCT was noted to correlate with cone density and visual function in this pilot study.


Assuntos
Células Fotorreceptoras Retinianas Cones , Doenças Retinianas , Tomografia de Coerência Óptica , Humanos , Contagem de Células , Estudos Transversais , Projetos Piloto , Retina , Tomografia de Coerência Óptica/métodos
15.
Am J Ophthalmol Case Rep ; 29: 101793, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36686264

RESUMO

Purpose: Acute Macular Neuroretinopathy (AMN) may be the result of deep retinal capillary plexus (DCP) impairment, but its mechanism remains elusive. A recent study has described simultaneous onset of Paracentral Acute Middle Maculopathy (PAMM) and AMN, suggesting a related pathogenic pathway. In this report, we analyze and describe the imaging characteristics of patients with concomitant Central Retinal Artery Occlusion (CRAO) and AMN and suggest a mechanistic pathway to explain this relationship. Observations: A total of 2 cases of CRAO, arteritic and non arteritic, were included in this report. At initial presentation, outer retinal layers were intact. At the two-week follow-up visit, both cases displayed Henle fiber layer hyperreflectivity and ellipsoid zone disruption consistent with AMN. Conclusions: Secondary development of AMN in CRAO is a new finding. DCP ischemia secondary to CRAO may lead to Henle fiber layer disruption, leading to the characteristic findings of AMN.

16.
J Integr Plant Biol ; 65(3): 721-738, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36263896

RESUMO

In plants, cortical microtubules anchor to the plasma membrane in arrays and play important roles in cell shape. However, the molecular mechanism of microtubule binding proteins, which connect the plasma membrane and cortical microtubules in cell morphology remains largely unknown. Here, we report that a plasma membrane and microtubule dual-localized IQ67 domain protein, IQD21, is critical for cotyledon pavement cell (PC) morphogenesis in Arabidopsis. iqd21 mutation caused increased indentation width, decreased lobe length, and similar lobe number of PCs, whereas IQD21 overexpression had a different effect on cotyledon PC shape. Weak overexpression led to increased lobe number, decreased indentation width, and similar lobe length, while moderate or great overexpression resulted in decreased lobe number, indentation width, and lobe length of PCs. Live-cell observations revealed that IQD21 accumulation at indentation regions correlates with lobe initiation and outgrowth during PC development. Cell biological and genetic approaches revealed that IQD21 promotes transfacial microtubules anchoring to the plasma membrane via its polybasic sites and bundling at the indentation regions in both periclinal and anticlinal walls. IQD21 controls cortical microtubule organization mainly through promoting Katanin 1-mediated microtubule severing during PC interdigitation. These findings provide the genetic evidence that transfacial microtubule arrays play a determinant role in lobe formation, and the insight into the molecular mechanism of IQD21 in transfacial microtubule organization at indentations and puzzle-shaped PC development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Microtúbulos/metabolismo , Arabidopsis/metabolismo , Katanina/metabolismo , Morfogênese
17.
Graefes Arch Clin Exp Ophthalmol ; 261(4): 925-933, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36326950

RESUMO

PURPOSE: To investigate the changes in the external limiting membrane (ELM), ellipsoid zone (EZ), and interdigitation zone (IZ) integrity and their relationship with visual outcomes after idiopathic epiretinal membranes peeling. METHODS: Clinical records of 150 eyes from 144 consecutive patients who underwent vitrectomy were reviewed. The status of IZ, EZ, and ELM was assessed by spectral-domain optical coherence tomography at baseline and 1, 4, 10, and 24 months postoperatively. RESULTS: Sixty-one eyes presented with photoreceptor layer disruption preoperatively, and IZ disruption (40.7%) was the primary type. The best-corrected visual acuity (BCVA) in the photoreceptor disruption group was significantly lower than that in the intact group at baseline and the final follow-up. Of them, ELM + EZ + IZ disruption showed the worst BCVA (P = 0.001). After surgery, 62 eyes were observed with disruption aggravated. EZ + IZ disruption (51.0%) was the most frequent type at 1 month postoperatively. The eyes with longer symptom duration, better BCVA, earlier stage, thinner CFT at baseline, and combined cataract surgery more tended to be observed with photoreceptor damage progressed after surgery (P < 0.05). There was no significant difference in the final BCVA between the eyes with and without damage progressed (P = 0.332). Finally, 28.1% of the eyes recovered photoreceptor continuity. The eyes with foveal photoreceptor integrity restored had better BCVA than those remaining discontinuous (P < 0.001). CONCLUSION: ERM-induced photoreceptor disruption mainly manifests as IZ disruption and has a negative effect on BCVA, whereas surgery mainly causes EZ and IZ disruption, which does not have a significant impact on the final BCVA.


Assuntos
Extração de Catarata , Membrana Epirretiniana , Humanos , Membrana Epirretiniana/diagnóstico , Membrana Epirretiniana/cirurgia , Acuidade Visual , Fóvea Central , Retina , Tomografia de Coerência Óptica/métodos , Vitrectomia , Estudos Retrospectivos
18.
Diagnostics (Basel) ; 12(11)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36428834

RESUMO

Assessment of midpalatal suture maturation is crucial before deciding which type of maxillary expansion technique will be performed to treat transverse discrepancies. In 2013, Angelieri et al. proposed a new method to evaluate midpalatal maturation using cone-beam computed tomography. The aim of this study was to systematically identify, evaluate, and provide a synthesis of the existing literature about this new method and to rigorously assess the methodological quality of these articles. A bibliographic search was carried out using PubMed, Cochrane Library, SciELO, LILACS, Web of Science, and Scopus using the terms midpalatal suture, cranial sutures, palate, maturation, interdigitation, ossification, maxillary expansion, evaluation, assessment, and assess. Quality assessment was performed using the Observational Cohort and Cross-Sectional Studies tool developed by the National Heart, Lung, and Blood Institute. Hence, 56 articles were obtained, of which only 10 met the selection criteria. We could not include any of the data into an analysis because of the large variation of the data collected and high methodological heterogeneity found among studies. Of all the studies included, 10% had poor quality, 70% fair, and 20% good quality, respectively. Even though age and sex play a role in midpalatal suture obliteration, there is a poor correlation between these variables. Thus, every patient should be assessed individually before choosing the best protocol for maxillary expansion. The midpalatal suture maturation method has the potential to be used for diagnostic purposes, but clinicians should be cautious of routinely using it because an extensive training and calibration program should be performed prior.

19.
Am J Ophthalmol Case Rep ; 28: 101706, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36187441

RESUMO

Purpose: To determine the changes in the microstructures of the photoreceptors in patients with autosomal recessive bestrophinopathy (ARB) by ultrahigh-resolution spectral-domain optical coherence tomography (UHR-SD-OCT). Methods: Five eyes of 4 patients with ARB were studied. Cross-sectional images of the fovea were recorded by the UHR-SD-OCT system with a depth resolution of <2.0 µm. Results: The UHR-SD-OCT images revealed changes in the outer retinal structures that were dependent on the severity of the photoreceptor atrophy. There was an increase in the reflectivity and appearance of small hyperreflective dots (HRDs) in the outer segments, followed by an irregularity and decrease in the length of the outer segments, then a disruption of the ellipsoid zone (EZ) band, and appearance of large HRDs corresponding to the segmented ellipsoids. Finally, there was a disappearance of the large HRDs followed by a localized thinning of the outer nuclear layer and appearance of hyperreflective foci above the region of the disrupted EZ. Conclusions: UHR-SD-OCT can record images that show detailed changes of the microstructures of the photoreceptors at different stages of ARB. These observations should help in determining the mechanisms involved in retinal pathology and should provide important information on the effectiveness of treatments.

20.
Biochim Biophys Acta Biomembr ; 1864(10): 184007, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35863424

RESUMO

The human skin provides a physiochemical and biological protective barrier due to the unique structure of its outermost layer known as the Stratum corneum. This layer consists of corneocytes and a multi-lamellar lipid matrix forming a composite, which is a major determining factor for the barrier function of the Stratum corneum. A substantiated understanding of this barrier is necessary, as controlled breaching or modulation of the same is also essential for various health and personal care applications such as topical drug delivery and cosmetics to a name few. In this study, we discuss the state-of-the-art of neutron diffraction techniques, using specifically deuterated lipids, combined with the information obtained from molecular models using molecular dynamics simulations, to understand the structure and barrier function of the Stratum corneum lipid matrix. As an example, the effect of ceramide concentration on a lipid lamella system consisting of CER[NP]/CER[AP]/Cholesterol/free fatty acid (deprotonated) is studied. This study demonstrates the usefulness of the combined approach of neutron diffraction and molecular dynamics simulations for effective analysis of the model systems created for the Stratum corneum lipid matrix. The optimization of force fields by comparison with experimental data is furthermore an important step in the direction of providing a predictive quality.


Assuntos
Nanoestruturas , Difração de Nêutrons , Ceramidas/química , Epiderme/química , Humanos , Simulação de Dinâmica Molecular , Nanoestruturas/química
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