scholarly journals Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process

2021 ◽  
Author(s):  
Sergio Alexandre Gehrke

The research and development of new implant models modifying the micro and macro design has increased significantly in the last decades. With the advancement of knowledge about the biological behavior of these materials when implanted in living tissue, a great search for morphological changes at macrogeometric, microgeometric and even nanogeometric levels was started, to accelerate the process of osseointegration of implants, reducing the time for the rehabilitation treatment. This chapter will seek to demonstrate, through scientific evidence, the potential effect of the morphological characteristics of implants on osseointegration. Modifications in the surface treatment of implants will be discussed to improve the osseointegration process in terms of quality and time reduction, changes in the surgical technique used for the osteotomy of the implant installation site, and macrogeometric changes in the shape of the implant body.

2020 ◽  
Vol 24 (3) ◽  
pp. 64-71
Author(s):  
A. V. Sukalo ◽  
I. A. Kazyra

INTRODUCTION. Among systemic vasopathies in children, IgA vasculitis Henoch Schoenlein (HS) is the most common, according to various authors, kidney damage is noted in 25-80 % and usually determines the prognosis of the disease.THE AIM of the study was to analyze clinical, laboratory, immunological, morphological characteristics, features of the course and treatment of nephritis associated with IgA vasculitis HS in children, as well as factors affecting the prognosis.PATIENTS AND METHODS. The study included 31 patients with morphologically verified nephritis due to IgA vasculitis HS (18 – boys, 13 – girls) aged 3 to 17 years, who were monitored at the Nephrology Department of the "2nd Children's City Clinical Hospital" of the National Center for Pediatric Nephrology and Renal Replacement therapy in Minsk from 2010 to 2019 yrs.The following parameters were analyzed: the clinical variant of kidney damage, laboratory tests (including the study of BAFF, RANTES lymphocyte activation molecules, pro-inflammatory IL1β, caspase1, TNFα, growth factors VEGF, TGF), 24 hours monitoring and office blood pressure measurements, ECHO cardiography with indicescalculation, ultrasound of the carotid arteries with the thickness of intima-media complex, morphological changes in the renal tissue, as well as treatment regimens.RESULTS. The contribution of deGal-IgA1, markers of T and B lymphocytes activation, pro-inflammatory and profibrotic molecules in the development of the disease is shown. Arterial hypertension was registered in 42 % of children, signs of heart remodeling according to the calculated indices in 19,3 %. Decrease level of adiponectin, vitamin D, leptin, increase concentration of obestatin, Pro-BNP, hs-CRP, and TSAT indicator classify patients with nephritis due to IgA vasculitis HS at moderate risk for the developmentof cardio-vascular disorders, which suggests the need for timely correction.CONCLUSION. In most cases, nephritis with IgA vasculitis HS has a benign course with rare relapses and progression to the end stage of chronic kidney disease (6,5 %).


2020 ◽  
Vol 16 (6) ◽  
pp. 774-781
Author(s):  
Liang Wu ◽  
An Kang ◽  
Yujie Lin ◽  
Chenxiao Shan ◽  
Zhu Zhou ◽  
...  

Background: Ilexsaponin A1, one of the most representative triterpene saponin components in the roots of I. pubescens, showed its effects in anticoagulation and antithrombosis, attenuating ischemia-reperfusion-induced myocardial, angiogenesis and inhibiting phosphodiesterase. Objective: Reveal the key intestinal bacterial strains responsible for ilexsaponin A1 metabolism, and clarify their metabolic behavior. Methods: An accurate and sensitive LC-MS/MS method for the determination of “ilexsaponin A1 in General Anaerobic Medium (GAM) broth” was established and systematically validated. Then it was applied to screen and study the metabolic potential of the intestinal bacterial strains in an anaerobic incubation system. Results: Quantitation of ilexsaponin A1 could be performed within an analytical run time of 14.5 min, in the linear range of 2 - 2000 ng/ml. Enterobacter sakazakii, Bifidobacterium breve, Bifidobacterium adolescentis, Bifidobacterium catenulatum, and Bifidobacterium angulatum were identified to have a potential effect to metabolize ilexsaponin A1 to different extents; and further bacterial metabolic studies were performed to clarify their metabolic capacity and behavior. Conclusion: This paper contributes to a better understanding of the intestinal bacterial metabolism of ilexsaponin A1 and provides scientific evidence for its clinical application. Additionally, the importance of intestinal bacterial strains in the disposition of natural products was also highlighted.


2021 ◽  
Vol 8 (2) ◽  
pp. 9
Author(s):  
Nina C. Wunderlich ◽  
Siew Yen Ho ◽  
Nir Flint ◽  
Robert J. Siegel

The morphological changes that occur in myxomatous mitral valve disease (MMVD) involve various components, ultimately leading to the impairment of mitral valve (MV) function. In this context, intrinsic mitral annular abnormalities are increasingly recognized, such as a mitral annular disjunction (MAD), a specific anatomical abnormality whereby there is a distinct separation between the mitral annulus and the left atrial wall and the basal portion of the posterolateral left ventricular myocardium. In recent years, several studies have suggested that MAD contributes to myxomatous degeneration of the mitral leaflets, and there is growing evidence that MAD is associated with ventricular arrhythmias and sudden cardiac death. In this review, the morphological characteristics of MAD and imaging tools for diagnosis will be described, and the clinical and functional aspects of the coincidence of MAD and myxomatous MVP will be discussed.


2021 ◽  
pp. 34-43
Author(s):  
Evgeniia A. Grigoreva ◽  
Valentina S. Gordova ◽  
Valentina E. Sergeeva ◽  
Alina T. Smorodchenko

The article presents data on the long-term effect (nine months) of a silicon compound supplied with drinking water – nonahydrate sodium metasilicate (10 mg/l in terms of silicon), on CD68-positive macrophages in the liver and spleen of laboratory rats. Changes in the morphological characteristics of this cell population were found. There was a decrease in the average cell area (in the liver of the control group of rats, the average macrophage area was 179.23±5.94 microns2, and in the group receiving silicon with drinking water – 117.04±3.35 microns2; in the spleen-136.02±3.93 microns2 and 103.44±2.8 microns2, respectively). Macrophages in the liver preparations of the experimental group of rats had a fewer processes and a darker cytoplasmic membrane. The number of macrophages in the liver per unit area was comparable, for the control group of rats it was 18.78±1.24, and for the rats that received with water with the addition of silicon – 19.41±0.75 cells. CD68+ macrophages of the red splenic pulp in laboratory rats that received silicon also underwent the following morphological changes: they were located in a denser way and had fewer processes, while the number of macrophages per unit area was 73.7±2.3 for the control group, 91.6±5.0-for the experimental group, respectively. The distance between them did not change. There was a change in the intensity of CD68 expression on the surface of the cytoplasmic membrane and in the cytoplasm of liver and spleen macrophages. These changes can be interpreted as the adaptive ability of liver and spleen macrophages to silicon introduced with drinking water. Given the heterogeneity of the macrophage population in the liver and spleen, further studies using markers for different subpopulations of macrophages are needed to clarify their role in the response of tissues to silicon supplied with drinking water.


2019 ◽  
Vol 11 (4) ◽  
pp. 445 ◽  
Author(s):  
Yingzhi Cao ◽  
Yichen Wu ◽  
Zhixiang Fang ◽  
Xiaojian Cui ◽  
Jianfeng Liang ◽  
...  

The world’s largest macroalgal blooms, Ulva prolifera, have appeared in the Yellow Sea every summer on different scales since 2007, causing great harm to the regional marine economy. In this study, the Normalized Difference of Vegetation Index (NDVI) index was used to extract the green tide of Ulva prolifera from MODIS images in the Yellow Sea in 2016–2018, to investigate its spatiotemporal patterns and to calculate its occurrence probability. Using the standard deviational ellipse (SDE), the morphological characteristics of the green tide, including directionality and regularity, were analyzed. The results showed that the largest distribution and coverage areas occurred in 2016, with 57,384 km2 and 2906 km2, respectively and that the total affected region during three years was 163,162 km2. The green tide drifted northward and died out near Qingdao, Shandong Province, which was found to be a high-risk region. The coast of Jiangsu Province was believed to be the source of Ulva prolifera, but it was probably not the only one. The regularity of the boundary shape of the distribution showed a change that was opposite to the variation of scale. Several sharp increases were found in the parameters of the SDE in all three years. In conclusion, the overall situation of Ulva prolifera was still severe in recent years, and the sea area near Qingdao became the worst hit area of the green tide event. It was also shown that the sea surface wind played an important part in its migration and morphological changes.


2019 ◽  
Vol 34 (4) ◽  
Author(s):  
Ana Paula Gurjão da Silva ◽  
Juan Eduardo Rios Rodriguez ◽  
Maria Conceição de Oliveira ◽  
Róbson Miguel de Araújo Negreiros ◽  
Leonardo Pessoa Cavalcante

2002 ◽  
Vol 9 (5) ◽  
pp. 652-664 ◽  
Author(s):  
James T. Lee ◽  
Jason Lee ◽  
Ihab Aziz ◽  
Carlos E. Donayre ◽  
Irwin Walot ◽  
...  

Purpose: To evaluate the outcome of aortic endografts deployed in large infrarenal necks and to identify any association of preoperative aneurysm characteristics and postoperative morphological changes with the incidence of neck dilatation and device migration in this patient subset. Methods: The records of 47 patients (41 men; mean age 74, range 55–84) with large aortic neck diameters treated with Talent stent-grafts from 1998 to 2001 were reviewed. Patients with anatomical criteria that precluded aneurysm exclusion with currently available devices were preferentially selected. Mean baseline aneurysm morphology included 27.6-mm (range 18–33.4) suprarenal and 28.1-mm (range 24–34) infrarenal neck diameters; the infrarenal neck length was 26 ± 16 mm with angulation of 37° ± 18°. Computed tomographic (CT) angiograms up to 3 years were analyzed using specialized interactive software; migration was defined as >1-cm change in the distance from the lower renal artery to the top of the device. Pre- and postoperative morphological characteristics of the aneurysm were compared between patients with and without migration. Results: Of the 45 patients successfully treated, 40 had complete CT data for analysis. During a mean 17-month follow-up, 7 (17.5%) of the 40 devices exhibited distal migration. Six patients required secondary procedures; 5 were in the migration cohort. No preoperative anatomical characteristic or degree of neck dilatation over time was predictive of stent-graft migration. Aneurysm sac regression was significant at 1 (–0.09 ± 4.90 mm) and 2 (–1.48 ± 2.56 mm) years in endografts without migration (p<0.001). Distal endograft migration >1 cm predicted the need for secondary interventions (p<0.001), with 83% sensitivity and 94% specificity. Conclusions: Endovascular repair is successful in patients with large infrarenal necks and complex neck morphology. Changes in aneurysm remodeling over time were similar to reported observations in patients with more favorable neck criteria. Although no anatomical factor associated with migration could be identified from this analysis, distal displacement >1 cm correlated with the need for a secondary intervention.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
M Araki ◽  
T Yonetsu ◽  
O Kurihara ◽  
A Nakajima ◽  
H Lee ◽  
...  

Abstract Background Two patterns of plaque progression have been described: slow linear progression and rapid step-wise progression. The former will cause stable angina when the narrowing reaches a critical threshold, while the latter may lead to acute coronary syndromes or sudden cardiac death. Purpose The aim of the study was to identify morphologic predictors for rapid plaque progression. Methods Patients who had OCT imaging during the index procedure and follow-up angiography with a minimum of 6-month interval were selected. Non-culprit lesion was defined as a plaque with a diameter stenosis ≥30% on index angiogram. Lesion progression was defined as the decrease of angiographic minimum lumen diameter ≥0.4 mm at follow-up (mean, 7.1 months). Baseline morphological characteristics of the plaques with rapid progression were evaluated by OCT. In a subgroup with follow-up OCT imaging for plaques with progression, morphological changes from baseline to follow-up were assessed. Results Among 517 lesions, 50 lesions showed progression. These lesions had a significantly higher prevalence of lipid-rich plaque (76.0% vs. 50.5%), thin-cap fibroatheroma (TCFA) (20.0% vs. 5.8%), layered plaque (60.0% vs. 34.0%), macrophage accumulation (62.0% vs. 42.4%), microvessel (46.0% vs. 29.1%), plaque rupture (12.0% vs. 4.7%), and thrombus (6.0% vs. 1.1%), compared to those without progression. The multivariable analysis identified lipid-rich plaque [odds ratio (OR) 2.17, 95% confidence interval (CI) 1.02–4.62, p=0.045], TCFA (OR 5.85, 95% CI 2.01–17.03, p=0.001), and layered plaque (OR 2.19, 95% CI 1.03–4.17, p=0.040) as predictors of subsequent lesion progression. In a subgroup with follow-up OCT, a new layer was detected in 14/41 (34.1%) plaques. Conclusions Lipid-rich plaque, TCFA, and layered plaque were predictors of subsequent rapid plaque progression. A new layer, a signature of rapid progression through plaque disruption and healing, was detected in 1/3 of the cases. Funding Acknowledgement Type of funding source: None


Paleobiology ◽  
2020 ◽  
pp. 1-22 ◽  
Author(s):  
James C. Lamsdell

Abstract The occupation of new environments by evolutionary lineages is frequently associated with morphological changes. This covariation of ecotype and phenotype is expected due to the process of natural selection, whereby environmental pressures lead to the proliferation of morphological variants that are a better fit for the prevailing abiotic conditions. One primary mechanism by which phenotypic variants are known to arise is through changes in the timing or duration of organismal development resulting in alterations to adult morphology, a process known as heterochrony. While numerous studies have demonstrated heterochronic trends in association with environmental gradients, few have done so within a phylogenetic context. Understanding species interrelationships is necessary to determine whether morphological change is due to heterochronic processes; however, research is hampered by the lack of a quantitative metric with which to assess the degree of heterochronic traits expressed within and among species. Here I present a new metric for quantifying heterochronic change, expressed as a heterochronic weighting, and apply it to xiphosuran chelicerates within a phylogenetic context to reveal concerted independent heterochronic trends. These trends correlate with shifts in environmental occupation from marine to nonmarine habitats, resulting in a macroevolutionary ratchet. Critically, the distribution of heterochronic weightings among species shows evidence of being influenced by both historical, phylogenetic processes and external ecological pressures. Heterochronic weighting proves to be an effective method to quantify heterochronic trends within a phylogenetic framework and is readily applicable to any group of organisms that have well-defined morphological characteristics, ontogenetic information, and resolved internal relationships.


2010 ◽  
Vol 67 (6) ◽  
pp. 707-712 ◽  
Author(s):  
Julio César Ramos ◽  
Silvia Del Carmen Imhoff ◽  
Miguel Ángel Pilatti ◽  
Abelardo Carlos Vegetti

Plant soil compaction poses a serious problem to agriculture because it produces different types of changes in plant characteristics. No method has been implemented to date to use root morphological changes as indicators of soil compaction levels. Therefore, the aim of the present study was to evaluate whether or not the morphological changes in root apexes of soybean (Glycine max (L.) Merrill) can be used as indicators of soil compaction levels. To this end, a silt-loamy soil material (from a Typic Argiudoll, Esperanza series), sieved through a 2 mm mesh was used and the following soil bulk density levels were determined: 1.1, 1.3 and 1.5 g cm³ for which the corresponding mechanical resistances were < 0.1, 0.5 and 3.5 MPa, respectively. The distance from the apex to the first tertiary root and the root diameter at 1.5 cm from the apex were measured on the secondary root apexes. A form factor equal to the quotient between these two variables was subsequently calculated. An inverse relationship between soil mechanical impedance and secondary root length and form factor as well as a direct relationship with the secondary root diameter were observed. Changes in rhizodermis cells were also recorded. The following morphological characteristics were found to evidence the highest sensitivity to soil compaction: i) the form factor, ii) rhizodermis papillose cells, iii) apical malformations in root hairs, and iv) root diameter in expansion areas. Taken together, the morphological characteristics of root apexes could be considered to be indicative of soil compaction.


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