scholarly journals Histopathologic Evaluation of Polymer Supports for Pintucci-Type Keratoprostheses: an Animal Study

2019 ◽  
Author(s):  
Saeed Rahmani ◽  
Mozhgan Rezaei Kanavi ◽  
Mohammad Ali Javadi ◽  
Masoumeh Meskinfam Langroudi
Keyword(s):  
Large Area ◽  
Tissue Penetration ◽  
Tissue Ingrowth ◽  
Fibrovascular Tissue ◽  
Polymer Supports ◽  
Different Types ◽  
Histopathologic Evaluation ◽  
The Mean ◽  
Imagej Software ◽  
Fibrovascular Ingrowth

Purpose: To report histopathological findings for different types of polymers proposed as support for a Pintucci-type keratoprosthesis. Methods: Six polymers, including three types of polyesters (#1-3), one type of polytetrafluoroethylene (PTFE, #4), polyethylene (#5), and expanded polytetrafluoroethylene (ePTFE, #6) were evaluated. Four samples of each material were placed under the orbicularis oculi muscles of 12 rabbits. After five weeks, the samples were removed and evaluated histopathologically. Fibrovascular tissue ingrowths were investigated in terms of tissue penetration depth into the materials (graded as none, mild, moderate, and intense) and fibrovascular ingrowth area at the ultimate level of tissue penetrance. ImageJ software was used to calculate fibrovascular tissue area between the material fibers, and the mean area values were compared between the materials. Results: Polyester materials #1 and #3 demonstrated intense fibrovascular tissue penetration with a large fibrovascular ingrowth area; no overt tissue ingrowth was observed into material #6. The mean area of penetrated fibrovascular tissues was significantly different between materials (P < 0.001). Materials #2, #4, and #5 showed moderate fibrovascular tissue ingrowth and the area of presented fibrovascular tissue at the paracentral parts of material #4 was significantly smaller than that of materials #1 (P = 0.02) and #3 (P = 0.01). Conclusion: Two polyester materials that had relatively large pore sizes demonstrated a deep and large area of fibrovascular ingrowth. Given that material #3 is thicker and more consistent than material #1, the former can be used as the appropriate material for supporting the Pintucci-type keratoprosthesis.

scholarly journals Estimation of contrast-to-noise ratio in CT and CBCT images with varying scan settings in presence of different implant materials

2019 ◽  
Vol 48 (8) ◽  
pp. 20190139
Author(s):  
Emine Şebnem Kursun-Cakmak ◽  
Husniye Demirturk Kocasarac ◽  
Seval Bayrak ◽  
Gülbahar Ustaoğlu ◽  
Marcel Noujeim
Keyword(s):  
Image Quality ◽  
Imaging Modality ◽  
Cone Beam Ct ◽  
Medical Systems ◽  
Plastic Container ◽  
Implant Materials ◽  
Different Types ◽  
Noise Ratio ◽  
Titanium Grade ◽  
Imagej Software

Objectives: To assess the contrast-to-noise ratio (CNR) of four different types of dental implant materials in CT and cone beam CT (CBCT) images with varying scan settings. Methods: Four different types of implants: zirconium (Zr), titanium (Ti) Grade 4 and 5 and titanium–zirconium (Ti–ZrO2) alloy were placed in a 3% gelatin phantom in a cylindrical plastic container and scanned with two different CT machines (GE Medical systems and Toshiba Medical Systems) and one CBCT machine (I-CAT, Imaging Sciences International) with different voxel sizes of 0.2, 0.25, 0.3 and 0.4 mm. Images were analyzed using ImageJ software with the purpose of estimating the CNR. Results: The CNR obtained from images acquired with CT was lower than the CBCT with all voxel sizes tested. 0.3 and 0.4 mm voxel sizes exhibited the highest CNR (p < 0.05) that gives the best image quality. Among the implant materials tested, titanium Grade 5 has the highest levels of CNR while Zirconium has the lowest (p < 0.05). Conclusions: The optimum protocol for radiographic follow-up in areas near implants on the I-CAT is low-resolution settings (0.3 and 0.4 mm voxel sizes) which gave the highest CNR thus image quality. In presence of Zr implants, an alternative imaging modality (i.e., MRI) may be considered to avoid low-quality images.

scholarly journals Mudrock Microstructure: A Technique for Distinguishing between Deep-Water Fine-Grained Sediments

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 653
Author(s):  
Shereef Bankole ◽  
Dorrik Stow ◽  
Zeinab Smillie ◽  
Jim Buckman ◽  
Helen Lever
Keyword(s):  
Grain Size ◽  
Deep Water ◽  
Sedimentary Facies ◽  
X Ray Diffraction ◽  
Weak Current ◽  
Large Area ◽  
Fine Grained ◽  
Mean Size ◽  
The Mean ◽  
Water Facies

Distinguishing among deep-water sedimentary facies has been a difficult task. This is possibly due to the process continuum in deep water, in which sediments occur in complex associations. The lack of definite sedimentological features among the different facies between hemipelagites and contourites presented a great challenge. In this study, we present detailed mudrock characteristics of the three main deep-water facies based on sedimentological characteristics, laser diffraction granulometry, high-resolution, large area scanning electron microscopy (SEM), and the synchrotron X-ray diffraction technique. Our results show that the deep-water microstructure is mainly process controlled, and that the controlling factor on their grain size is much more complex than previously envisaged. Retarding current velocity, as well as the lower carrying capacity of the current, has an impact on the mean size and sorting for the contourite and turbidite facies, whereas hemipelagite grain size is impacted by the natural heterogeneity of the system caused by bioturbation. Based on the microfabric analysis, there is a disparate pattern observed among the sedimentary facies; turbidites are generally bedding parallel due to strong currents resulting in shear flow, contourites are random to semi-random as they are impacted by a weak current, while hemipelagites are random to oblique since they are impacted by bioturbation.

scholarly journals Incidence and Characteristics of Retinoblastoma in Poland: The First Nationwide Study 2010–2017

2021 ◽  
Vol 18 (12) ◽  
pp. 6539
Author(s):  
Michał S. Nowak ◽  
Bożena Romanowska-Dixon ◽  
Iwona Grabska-Liberek ◽  
Michał Żurek
Keyword(s):  
Western Europe ◽  
External Beam Radiotherapy ◽  
Cohort Analysis ◽  
Developed Countries ◽  
Live Births ◽  
Focal Treatment ◽  
Different Types ◽  
The Mean ◽  
Birth Cohort Analysis

Background: The present study aimed to investigate the incidence and characteristics of retinoblastoma in the overall population of Poland. Methods: The retrospective survey of both National Health Fund (NHF) and National Cancer Registry (NCR) databases were performed to identify all retinoblastoma cases in Poland in the years 2010–2017. Results: During 2010–2017, the mean age-standardised incidence of retinoblastoma (the unit of incidence is per 1,000,000 person-years) was 10.15 (95% CI 7.23–13.08) among children aged 0 to 4 years and 5.39 (95% CI 4.18–6.60) in those aged 0 to 9 years. During 2010–2014 (to allow 5 years of follow-up), the mean incidence of retinoblastoma by birth cohort analysis in Poland was 4.89 (95% CI 4.04–5.74) per 100,000 live births, corresponding to an incidence of 1 per 20,561 (95% CI 15,855–25,267) live births. In Poland, 14.6% of children with retinoblastoma had enucleation of the eye globe, 76.8% received different types of chemotherapy combined with focal treatment, 5.9% were treated with external beam radiotherapy, and 2.7% were treated with focal treatments only. Conclusions: The incidence of retinoblastoma and the pattern of medical management of retinoblastoma in Poland was similar to that reported in developed countries in Western Europe, Asia, and North America.

scholarly journals Does Every Calculation Formula Fit for All Types of Intraocular Lenses? Optimization of Constants for Tecnis ZA9003 and ZCB00 Is Necessary

Medicina ◽  
2021 ◽  
Vol 57 (4) ◽  
pp. 319
Author(s):  
Ivajlo Popov ◽  
Veronika Popova ◽  
Juraj Sekac ◽  
Vladimir Krasnik
Keyword(s):  
Prediction Error ◽  
Poor Performance ◽  
Intraocular Lenses ◽  
Power Calculation ◽  
Universal Formula ◽  
Aspheric Iol ◽  
Different Types ◽  
The Mean ◽  
Clinically Significant ◽  
Mean Prediction Error

Background and Objectives: To evaluate the performance of intraocular lenses (IOLs) using power calculation formulas on different types of IOL. Materials and Methods: 120 eyes and four IOL types (BioLine Yellow Accurate Aspheric IOL (i-Medical), TECNIS ZCB00, TECNIS ZA9003 (Johnson & Johnson) (3-piece IOL) and Softec HD (Lenstec)) were analyzed. The performance of Haigis, Barret Universal II and SKR-II formulas were compared between IOL types. The mean prediction error (ME) and mean absolute prediction error (MAE) were analyzed. Results: The overall percentage of eyes predicted within ±0.25 diopters (D) was 40.8% for Barret; 39.2% Haigis and 31.7% for SRK-II. Barret and Haigis had a significantly lower MAE than SRK-II (p < 0.05). The results differed among IOL types. The largest portion of eyes predicted within ±0.25 D was with the Barret formula in ZCB00 (33.3%) and ZA9003 (43.3%). Haigis was the most accurate in Softec HD (50%) and SRK-II in Biolline Yellow IOL (50%). ZCB00 showed a clinically significant hypermetropic ME compared to other IOLs. Conclusions: In general, Barret formulas had the best performance as a universal formula. However, the formula should be chosen according to the type of IOL in order to obtain the best results. Constant optimizations are necessary for the Tecnis IOL ZCB00 and ZA9003, as all of the analyzed formulas achieved a clinically significant poor performance in this type of IOL. ZCB00 also showed a hypermetropic shift in ME in all the formulas.

Disability in Schizophrenic Disorders

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
J. Wancata ◽  
M. Freidl ◽  
F. Friedrich ◽  
T. Matschnig ◽  
A. Unger ◽  
...  
Keyword(s):  
Hospital Admissions ◽  
Social Consequences ◽  
Subjective Burden ◽  
Social Contacts ◽  
Mothers And Fathers ◽  
Duration Of Illness ◽  
The Family ◽  
Different Types ◽  
Icd 10 ◽  
The Mean

Aims:The purpose of this study was to investigate disability among patients suffering from schizophrenia and to identify predictors of disability.Methods:101 patients from different types of psychiatric services in Vienna and diagnosed with schizophrenia according to ICD-10 were included. They were investigates by means of 36-Item self-administered version of the WHO Disability Assessment Schedule II (WHO-DAS-II) and the PANSS-scale. Patients’ mothers and fathers were asked to fill in the Family Problem Questionnaire.Results:The mean total score of the WHO-DAS-II was 74.1 (SD 21.9). When using weighted sub-scores the highest disability scores were found for social contacts, participation in society and household (means 2.58, 2.57 and 2.51 respectively). Using logistic regression, overall disability was positively associated with patient's age, overall severity of symptoms (PANSS) and number of previous hospital admissions. Overall disability was not associated with duration of illness and or patient's gender. The subjective burden experienced by patients’ fathers and mothers were increased by reduced social contacts and impaired participation in society, while we could not find an association with other domains of patient's disability (understanding, mobility, self-care, household).Conclusions:This study shows that schizophrenia results in disability in several domains. Family caregivers’ burden was predominantly increased by social consequences of schizophrenia.

OBSERVATIONS INDICATING A SEX CYCLE IN THE MALE RABBIT

1964 ◽  
Vol 46 (4) ◽  
pp. 597-607 ◽  
Author(s):  
Jan Erik Kihlström ◽  
Otto Hornstein
Keyword(s):  
Body Temperature ◽  
Mucous Membrane ◽  
Immature Stage ◽  
Male Urethra ◽  
Male Rabbit ◽  
Exfoliated Cells ◽  
Different Types ◽  
The Mean ◽  
Male Sex ◽  
Sex Cycle

ABSTRACT Recently some physiological characteristics of a sex cycle in male animals have been demonstrated. However, nothing is known at present about any morphological expressions of this cycle, and particularly about any rhythmical variation in exfoliation of cells comparable with that of the vaginal mucous membrane. On the assumption that such a rhythm may occur in the male urethra, the exfoliation of cells in this organ has been studied by taking daily smears. Cyclically varying frequencies of four different types of exfoliated cells, mainly in an immature stage, were demonstrated. Only a fifth type of cells, characterized by cornification and nuclear degeneration, is not subjected to such rhythmical variation. The mean duration of these cycles is about four days. Simultaneous investigations on the seminal volume and body temperature showed some relation to the cycle of cell desquamation. The results give additional evidence for the existence of a male sex cycle, probably with a hormonal background.

The growth of supernumerary legs in the cockroach

Development ◽  
1986 ◽  
Vol 92 (1) ◽  
pp. 115-131
Author(s):  
Paul R. Truby
Keyword(s):  
Wound Healing ◽  
Cell Division ◽  
Rapid Rate ◽  
Large Area ◽  
Anteroposterior Axis ◽  
Cell Divisions ◽  
Leucophaea Maderae ◽  
Different Types ◽  
Local Cell

When the anteroposterior axis of a cockroach leg is reversed at a graft by exchanging a left leg for a right leg at the mid-tibia level, regeneration occurs in the region of the graft/host junction. This results in the formation of a pair of lateral supernumerary legs. In these experiments the patterns of cell division which take place during supernumerary leg formation were observed in sections of regenerating legs of the cockroach Leucophaea maderae. Early patterns of cell division resemble those seen in control grafts in which no axial reversal had been carried out during grafting. These cell divisions are associated with the process of wound healing. Later, a large area of the epidermis proximal to the graft/host junction becomes activated and shows a rapid rate of cell division. This area forms two outgrowths which grow by cell division throughout their epidermis to form the epidermis of the supernumerary legs. The results are more consistent with the view that the formation of supernumerary legs involves dedifferentiation of the epidermis in the region of the graft/host junction to form a blastema, rather than being due to local cell division at the point of maximum pattern discontinuity. This conclusion is used to offer an explanation for the range of different types of outcome of left-right grafts that has been observed.

Properties of Unitary IPSCs in Hippocampal Pyramidal Cells Originating From Different Types of Interneurons in Young Rats

1997 ◽  
Vol 77 (4) ◽  
pp. 1939-1949 ◽  
Author(s):  
Mohamed Ouardouz ◽  
Jean-Claude Lacaille
Keyword(s):  
Reversal Potential ◽  
Pyramidal Cells ◽  
Mean Amplitude ◽  
Paired Pulse ◽  
Young Rats ◽  
Different Types ◽  
The Mean ◽  
Paired Pulse Depression ◽  
Types Of Interneurons ◽  
Stimulation Of

Ouardouz, Mohamed and Jean-Claude Lacaille. Properties of unitary IPSCs in hippocampal pyramidal cells originating from different types of interneurons in young rats. J. Neurophysiol. 77: 1939–1949, 1997. Whole cell recordings were used in hippocampal slices of young rats to examine unitary inhibitory postsynaptic currents (uIPSCs) evoked in CA1 pyramidal cells at room temperature. Loose cell-attached stimulation was applied to activate single interneurons of different subtypes located in stratum oriens (OR), near stratum pyramidale (PYR), and at the border of stratum radiatum and lacunosum-moleculare (LM). uIPSCs evoked by stimulation of PYR and OR interneurons had similar onset latency, rise time, peak amplitude, and decay. In contrast, uIPSCs elicited by activation of LM interneurons were significantly smaller in amplitude and had a slower time course. The mean reversal potential of uIPSCs was −53.1 ± 2.1 (SE) mV during recordings with intracellular solution containing potassium gluconate. With the use of recording solution containing the potassium channel blocker cesium, the reversal potential of uIPSCs was not significantly different (−58.5 ± 2.6 mV), suggesting that these synaptic currents were not mediated by potassium conductances. Bath application of the γ-aminobutyric acid-A (GABAA) receptor antagonist bicuculline (25 μM) reversibly blocked uIPSCs evoked by stimulation of all interneuron subtypes. In bicuculline, the mean peak amplitude of uIPSCs recorded with potassium gluconate was reduced to 3.5 ± 4.4% of control ( n = 7). Similarly, with cesium methanesulfonate, the mean amplitude in bicuculline was 2.9 ± 3.1% of control ( n = 13). Application of the GABAB receptor antagonist CGP 55845A (5 μM) resulted in a significant and reversible increase in the mean amplitude of uIPSCs recorded with cesium-containing intracellular solution. Thus uIPSCs from all cell types appeared under tonic presynaptic inhibition by GABAB receptors. Paired stimulation of individual interneurons at 100- to 200-ms intervals did not result in paired pulse depression of uIPSCs. For individual responses, a significant negative correlation was observed between the amplitude of the first and second uIPSCs. A significant paired pulse facilitation (154.0 ± 8.0%) was observed when the first uIPSC was smaller than the mean of all first uIPSCs. A small, but not significant, paired pulse depression (90.8 ± 4.0%) was found when the first uIPSC was larger than the mean of all first uIPSCs. Our results indicate that these different subtypes of hippocampal interneurons generate Cl−-mediated GABAA uIPSCs. uIPSCs originating from different types of interneurons may have heterogeneous properties and may be subject to tonic presynaptic inhibition via heterosynaptic GABAB receptors. These results suggest a specialization of function for inhibitory interneurons and point to complex presynaptic modulation of interneuron function.

Occurrence of Aflatoxin M1 in Cheeses from the South of Spain

1996 ◽  
Vol 59 (8) ◽  
pp. 898-900 ◽  
Author(s):  
Mª JOSÉ BARRIOS ◽  
Mª JESÚS GUALDA ◽  
J. M. CABANAS ◽  
L. M. MEDINA ◽  
R. JORDANO
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Aflatoxin M1 ◽  
The South ◽  
Different Types ◽  
The Mean

Thirty-five samples of commercial cheeses, 9 fresh, 9 semicured or semiripened and 17 ripened made with different types of milk (cow, ewe, goat and mixtures of milk of various species) produced in the South of Spain were analyzed for the presence of aflatoxin M1 (AFM1) by high-performance liquid chromatography, In 16 of the 35 samples (45.71%) the presence of AFM1 was detected in concentrations ranging between 20 and 200 ng/g of cheese, In the positive cases, the mean levels of AFM1 were 105.33 ng/g in ripened cheeses, 73.80 ng/g in semiripened cheeses and 42.60 ng/g in fresh cheeses.

scholarly journals The anatomic rationale for transforaminal endoscopic interbody fusion: a cadaveric analysis

2016 ◽  
Vol 40 (2) ◽  
pp. E12 ◽  
Author(s):  
Mitchell Hardenbrook ◽  
Sergio Lombardo ◽  
Miles C. Wilson ◽  
Albert E. Telfeian
Keyword(s):  
Surface Area ◽  
Soft Tissues ◽  
Safe Zone ◽  
Large Area ◽  
Nerve Roots ◽  
Disc Space ◽  
Endoscopic Techniques ◽  
Pars Interarticularis ◽  
The Mean ◽  
Cadaveric Analysis

OBJECTIVE The authors describe a cadaveric analysis to determine the ideal dimensions and trajectory for considering endoscopic transforaminal interbody implantation. METHODS The soft tissues of 8 human cadavers were removed from L-1 to the sacrum, exposing the posterior bony elements. Facetectomies were performed bilaterally at each lumbar level with resection of the pars interarticularis, revealing the pedicles, nerve roots, and interbody disc space. Each level was digitally photographed with a marker for scale and evaluated with digital analysis software. The traversing and exiting nerve roots and pedicle margins were identified, and the distances between these structures and their relationships to the surrounding structures were documented. RESULTS The dimensions of 2 areas were measured: the working triangle and safe zone. The working triangle is the triangle between the exiting and traversing nerve roots above the superior margin of the inferior pedicle. The safe zone is the trapezoid bounded by the widths of the superior and inferior pedicles between the exiting and traversing nerve roots. The mean surface area for the working triangle was 1.83 cm2, with L5–S1 having the largest area at 2.19 cm2. The mean surface area of the safe zone was 1.19 cm2, with L5–S1 having the largest area at 1.26 cm2. At the medial border of the pedicle extending superiorly, there were no nerve structures within 1.19 cm at any level. On the lateral border of the pedicle, the exiting nerve root was closer superiorly, with the closest being 0.3 cm. CONCLUSIONS The working triangle is a relatively large area. The safe zone, just superior to the pedicle, is free of nerve structures. By utilizing the superior border of the pedicle, the disc space can be accessed within this safe zone without risk of injury to the nerves. A thorough understanding of foraminal anatomy is fundamental for considering how to safely access the disc space, thereby utilizing less invasive endoscopic techniques, and is an important first step in considering what shapes and sizes of interbody implants and retractors are feasible for use in the foramen.

Sign in / Sign up

Export Citation Format

Share Document