bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transoral Endoscopic Thyroidectomy via Vestibular Approach With 4 Trocars: A New Technique
Authors: Ngo Duy Quoc , Tran Toan Duc , Ngo Quy Xuan , Van Le Quang 
Published: August 2020

Objectives: The objective of this study was to report the feasibility and safety of a novel 4-trocar approach for transoral endoscopic thyroidectomy via the vestibular. Methods: In this study, we first used 4 trocars via vestibular area to perform transoral endoscopic thyroidectomy. We reported the safety and surgical feasibility of transoral endoscopic thyroidectomy using a 4-trocar technique in our institute from February 1, 2020, to May 10, 2020. Results: Transoral endoscopic thyroidectomy via the vestibular approach using 4 trocars was carried out in 5 patients. No complications such as bleeding, mental nerve injury, recurrent laryngeal nerve injury, or hypoparathyroidism were reported. All patients were completely satisfied with the cosmetic results. Conclusions: Transoral endoscopic thyroidectomy with 4 trocars via vestibular approach is an effective and feasible method. Markedly, this technique can assist surgeons to expose and preserve both parathyroid glands and recurrent laryngeal nerve easily when performing transoral endoscopic thyroidectomy.
The Bovine Lens as a Model for Osmotic Cataract
Authors: Marcantonio Julia M. 
Published: August 2020

Summary Bovine lenses, obtained from a commercial slaughterhouse, have been cultured successfully in a completely defined medium, for periods of up to two weeks. In control lenses, transparency is maintained, ionic balance and hydration are normal, and the amino acid L-tyrosine is in a steady state. Synthesis of the lens specific proteins continues throughout the culture period and there is no evidence of crystallin breakdown. Cultured lenses have been subjected to insult by various substances known to affect membrane function. In each case, ionic balance was disturbed, hydration was increased and there was gradual opacification of the lens. In addition, in the presence of ouabain, amino acid transport was decreased after a delay, while there was a very rapid reduction in protein synthesis. The cultured lens seems to be a very sensitive system which can be used as a model for investigations of normal function and for in vitro testing.
To What is the Alternative?
Authors: Worden Alastair N. 
Published: August 2020

Summary The value of conventional long-term, carcinogenicity or reproductive studies would in many instances appear to depend upon the “insurance” they are held to provide and upon “no effect” levels, rather than upon the production of adverse effects that can be extrapolated to man. The development of alternatives to such studies necessitates refinement of the latter and the investigation of specific components and mechanisms of toxicity.
Further Investigations on the Ileum Model as a Possible Alternative to In Vivo Eye Irritancy Testing
Authors: Muir C.K. 
Published: August 2020

Summary The concentration of six surfactants required to block spontaneous contractions of rabbit isolated ileum by 50% (EC50) correlated well with in vivo eye irritancy (correlation coefficient -0.996) only when fresh ileum was tested at 35°C. Storage of ileum for 2 hr or 4 hr before testing did not significantly alter the potency of five of the surfactants, but the potency of triethanolamine decyl sulphate (TDS), the only C-10 surfactant tested, was significantly reduced as compared to fresh controls. When tested on fresh ileum at 29°C all the surfactants, except TDS, were more potent at blocking contractions while TDS was significantly less potent. It is suggested that the penetration barrier to surfactants is considerably more complex than previously envisaged, possibly involving a transport system capable of concentrating TDS, but not the other agents tested. It would appear that, provided experimental conditions are carefully controlled, the ileum model can yield results which correlate well with in vivo ocular irritancy and as such may provide the basis for the development of a viable screen for irritancy of surfactants and surfactant-based products.
Effects of Fungizone on the In Vitro Cytotoxicity of Other Chemicals
Authors: Horner Steven A. , Shah Minesh K. 
Published: August 2020

Summary Fungizone, the deoxycholate complex of Amphotericin B, is widely used in tissue culture media as a precaution against contamination. However, a number of reports indicate that the polyenes are toxic to certain mammalian cell lines at relatively low concentrations and can potentiate the effects of other chemicals. The effects of Fungizone on the growth of cultured V79 Chinese hamster lung fibroblasts were determined: growth was inhibited at concentrations above 10μg/ml (ID50 = 13μg/ml), but Fungizone did not affect cell growth when present at the concentration recommended for use in tissue culture media (2μg/ml). This concentration of Fungizone was found to significantly increase the growth inhibitory effects of four toxicants with different modes of action; however, this effect is not considered sufficient to invalidate the inclusion of Fungizone in media used in cytotoxicity tests on cultured V79 cells.
Assessment of the Skin Irritancy Potential of Synthetic Detergents (Syndets)
Authors: Dykes P.J. , Williams D.L. , Jenner L.A. , Marks R. 
Published: August 2020

Summary Among the factors which determine the degree of damage to the skin are (a) the resistance of the stratum corneum to the solubilisation of its components, (b) the intrinsic toxicity of the compound, and (c) the susceptibility of the viable cell layers to damage. In this study of the toxicity of syndets we have attempted to compare their properties in vivo and in vitro and relate these to cutaneous irritancy studies in normal volunteers. The “solubilising” effect of a series of syndets has been studied using the forced desquamation technique. Although no differences could be determined in terms of the corneocytes released from the skin surface, the protein solubilised did differ according to the syndet used and a rank order could be obtained. The susceptibility of viable cells to lysis by syndets has been studied in vitro, using human skin fibroblasts. This test system was able to discriminate between the different syndets and gave the same rank order as the in vivo human test. Comparison with the standard cutaneous irritancy test indicated some correlation between the two test systems and the irritancy test. However, the rank order correlation did show some discrepancy, and the use of such test systems as predictors of cutaneous irritancy is still being investigated.
The Importance of Exposure Period and Cell Type in In Vitro Cytotoxicity Tests
Authors: Riddell R.J. , Panacer D.S. , Wilde S.M. , Clothier R.H. , Balls M. 
Published: August 2020

The cytotoxicities of 50 coded chemicals from the FRAME blind trial set were estimated by the FRAME kenacid blue (KB) and Rockefeller neutral red (NR) assay methods after test periods of 24 hours and 72 hours with murine 3T3 fibroblasts. Results obtained after the two test periods were considered to be similar for 25 of the chemicals, but different for 25 others. Our results indicate that a test period of 72 hours is more suitable for the assessment of potential cytotoxicity by the KB and NR methods than the 24 hour test period, which is less likely to allow sufficient time for certain chemicals to exert their toxic effects, particularly those that inhibit cell division or affect cell viability through other long-term effects. A comparison of results obtained by the 72 hour KB method with 3T3 cells and with human BCL-D1 cells indicated that substantially different ID50 values were found for 8 of 48 chemicals. These results are discussed in terms of the importance of choice of test period, assay method and cell type used in in vitro cytotoxicity tests.
Qualitative Differences in Opacification and Thickness of Bovine Cornea In Vitro Induced by Acid, Alkali, Surfactant or Methanol
Authors: Muir Colin K. 
Published: August 2020

Bovine corneas incubated at pH 2 for 4.5 hours became opaque but did not thicken. Corneas incubated at pH 12 became opaque and thickened. Removal of epithelium indicated that pH 2 had caused opacity predominantly in the epithelium itself, while pH 12 had predominantly opacified the stroma. With 5 x 10-3 M of the cationic surfactant, lauryl trimethylammonium bromide, in contact only with the outside (epithelium-side) of the cornea for up to 4 hours, the epithelium opacified but the stroma did not. There was no thickening for the first 2 hours of incubation, but significant thickening thereafter. Methanol 50% v/v in contact only with the outside of the cornea caused the epithelium to opacify within 2 minutes, but this effect diminished and a profound opacification of stroma developed over 4 hours. Gross thickening to over three times normal had developed after 4 hours of incubation. The results suggest that opacity can occur without thickening, but that thickening cannot occur without opacity. Opacity may therefore be a more reliable parameter than thickness for indicating toxic responses of the cornea.
Astroglial Receptors as Putative Targets for Neurotoxic Agents
Authors: Hansson Elisabeth , Rönnbäck Lars 
Published: August 2020

Astrocytes respond to neurotoxins and play a crucial role in metabolic and structural nerve tissue dysfunction in diseases, such as epilepsy, degenerative diseases, hepatic encephalopathy, and in other toxic states. The cells make up part of the blood/brain barrier, thus being “aware of” blood-borne substances which can penetrate into the nervous tissue. The cells also extend processes into the synaptic regions and probably regulate neuronal activity. Cells respond to changes in their environment by means of specific receptors that detect incoming signals and translate the information into a form that can be recognised by intracellular effector systems. Aspects of astrocyte receptors for neurotransmitters and neuromodulators, receptor interactions, second messenger systems and automodulation of genes after receptor activation are summarised as a basis for studies on the evaluation of the effects of neurotoxic substances and drugs.
Membrane Alterations Induced by Amphiphiles
Authors: Isomaa Boris , Hägerstrand Henry , Paatero Gun I.L. 
Published: August 2020

Amphiphilic compounds with distinct apolar and polar parts are readily intercalated into the erythrocyte membrane. When intercalated into the membrane, amphiphiles are probably orientated so that the polar head is at the polar-apolar interface of the lipid bilayer and the hydrophobic part within the apolar core of the bilayer. However, by virtue of their difference in molecular shape from the bulk lipids of the lipid bilayer, it is possible that the intercalated amphiphiles are partly segregated from bulk lipids and accumulate at protein-lipid interfaces in the bilayer, where the packing of the bilayer lipids may be less ordered. Our studies show that amphiphiles, when intercalated into the erythrocyte membrane, trigger alterations in several membrane-connected functions. Some of the alterations induced (decreased osmotic fragility, increased passive potassium fluxes) seem to be due to non-specific interactions of the amphiphiles with the membrane, whereas other functions (ion transport mediated by membrane proteins, regulation of cell shape) seem to be sensitive to particular features of the amphiphiles. Our studies indicate that the intercalation of amphiphiles into the erythrocyte membrane must involve rearrangements within the lipid bilayer. We have suggested that, when intercalated into the lipid bilayer, amphiphiles trigger a rapid formation of non-bilayer phases, which protect the bilayer against a collapse and bring about a trans-bilayer redistribution of intercalated amphiphiles as well as of bilayer lipids. At high sublytic concentrations, this process may also involve a release of microvesicles from the membrane.
Clinical and Radiographic Outcomes of Revision Total Ankle Arthroplasty Using an Intramedullary-Referencing Implant
Authors: Behrens Steve B. , Irwin Todd A. , Bemenderfer Thomas B. , Schipper Oliver N. , Odum Susan M. , Anderson Robert B. , Davis W. Hodges 
Published: August 2020

Background: Treatment of failed total ankle arthroplasty (TAA) is challenging. Limited literature is available on options and outcomes of revision arthroplasty despite failure rates ranging from 10% to 23% within 10 years after primary TAA. This study reports the clinical and radiographic outcomes of revision TAA using a fixed-bearing, intramedullary-referencing implant. Methods: A retrospective review was performed of 18 consecutive revision TAA cases between 2008-2015 using an intramedullary-referencing, fixed-bearing, 2-component total ankle system. Demographic and radiographic data were collected preoperatively, immediately postoperatively, and at the most recent follow-up. Functional outcome data were collected immediately postoperatively and at mean follow-up 47.5 months. Results: Eighteen patients underwent revision TAA, with 77.8% (14/18) implant survival. Index revision was performed most commonly for aseptic talar subsidence (55.6%) or implant loosening (tibia, 29.4%; talus, 58.9%). Following revision, 22.2% (4/18) patients required reoperation at a mean 57.3 (39-86) months. Osteolysis of the tibia, talus, and fibula was present preoperatively in 66.7% (12/18), 38.9% (7/18), and 38.9% (7/18) of patients, respectively, with progression of osteolysis in 27.8% (5/18), 11.1% (2/18) and 11.1% (2/18) of patients, respectively. Subsidence of the tibial and talar revision components was observed in 38.9% (7/18) and 55.6% (10/18) of patients, respectively. The median American Orthopaedic Foot & Ankle Society (AOFAS) score was 74.5 (26-100) and Foot Function Index (FFI) score 10.2 (0-50.4). Conclusion: Early results of intramedullary-referencing revision TAA demonstrated good patient-reported outcomes with maintenance of radiographic parameters at mean follow-up of 47.5 months. Aseptic talar subsidence or loosening were the main postoperative causes of reoperation. Revision arthroplasty utilizing an intramedullary-referencing implant was a viable option for the failed TAA. Level of Evidence: Level IV, case series.
Endothelin-1 in portal hypertension: The intricate role of hepatic stellate cells
Authors: Ezhilarasan Devaraj 
Published: August 2020

Portal hypertension is one of the most important cirrhosis-associated complications of chronic liver disease, leading to significant morbidity and mortality. After chronic liver injury, hepatic stellate cells reside in the perisinusoidal space activted and acquire a myofibroblast-like phenotype. The activated hepatic stellate cells act as both sources as well as the target for a potent vasoconstrictor endothelin-1. Activation of hepatic stellate cells plays a vital role in the onset of cirrhosis by way of increased extracellular matrix production and the enhanced contractile response to vasoactive mediators such as endothelin-1. In fibrotic/cirrhotic liver, activated hepatic stellate cells produce endothelin-1 leading to an imbalance between pro and antifibrotic factors responsible for enormous extracellular matrix synthesis. Thus, extracellular matrix deposition in the perisinusoidal space further augments liver stiffness and elevates the vascular tone and portal hypertension. Portal hypertension is a complex process modulated by several cell types like hepatic stellate cells, liver sinusoidal endothelial cells, Kupffer cells, injured hepatocytes, immune cells, and biliary epithelial cells. Therefore, targeting a single cell type may not be useful for regression of cirrhosis and portal hypertension. Nevertheless, numerous findings indicate that functionally liver sinusoidal endothelial cells and hepatic stellate cells closely regulate the sinusoidal blood flow via synthesis of several vasoactive molecules including endothelin-1, and hence targeting these cells with novel pharmacological agents may offer promising results. Impact statement Portal hypertension is pathologically defined as increase of portal venous pressure, mainly due to chronic liver diseases such as fibrosis and cirrhosis. In fibrotic liver, activated hepatic stellate cells increase their contraction in response to endothelin-1 (ET-1) via autocrine and paracrine stimulation from liver sinusoidal endothelial cells and injured hepatocytes. Clinical studies are limited with ET receptor antagonists in cirrhotic patients with portal hypertension. Hence, studies are needed to find molecules that block ET-1 synthesis. Accumulation of extracellular matrix proteins in the perisinusoidal space, tissue contraction, and alteration in blood flow are prominent during portal hypertension. Therefore, novel matrix modulators should be tested experimentally as well as in clinical studies. Specifically, tumor necrosis factor-α, transforming growth factor-β1, Wnt, Notch, rho-associated protein kinase 1 signaling antagonists, and peroxisome proliferator-activated receptor α and γ, interferon-γ and sirtuin 1 agonists should be tested elaborately against cirrhosis patients with portal hypertension.
COVID-19: How did community pharmacies get through the first wave?
Authors: Gregory Paul A. M. , Austin Zubin 
Published: August 2020

Background: The coronavirus disease 2019 (COVID-19) pandemic of early 2020 was one of the most impactful events in living memory. As an essential service, community pharmacies remained open to provide care and service. The unprecedented nature and scale of the pandemic triggered considerable change in daily practice. In anticipation of future pandemic waves and similar mass-scale civil disruptions, it is important to understand how community pharmacies adapted and responded in the early weeks of COVID-19. Methods: A combination of convenience, snowball and purposive sampling methods was used to recruit staff from community pharmacies across Ontario, from a variety of different practice locations and types. A semistructured focus group interview protocol was used to elicit experiences. Data gathering was undertaken until the point of saturation. Thematic analysis was used to surface common experiences and to describe how community pharmacies adapted and responded. Results: A total of 39 participants (pharmacists, registered technicians and assistants) from 11 different pharmacies participated in this study. Data were coded based on 1) what happened, 2) how community pharmacies responded, and 3) what worked and did not work to support pharmacy staff in continued provision of service and care. Key findings included the collapse of provision of nondispensing remunerated services, the central role of managerial decisions in supporting resilience (e.g., change to 8-hour shifts from 12-hour shifts) and the central role of technology in supporting continuity of quality pharmacy services. Discussion: With anticipated future pandemic waves, preparedness of community pharmacy will be essential. This study provides important insights based on participants’ own experiences regarding ways employers can better support staff in provision of care and service to patients during times of mass-scale civil disruption. Can Pharm J (Ott) 2020;153:xx-xx.
Non-infectious comorbidity in patients with multiple sclerosis: A national cohort study in Sweden
Authors: Castelo-Branco Anna , Chiesa Flaminia , Bengtsson Camilla E , Lee Sally , Minton Neil N , Niemcryk Steve , Lindholm Anders , Rosenlund Mats , Piehl Fredrik , Montgomery Scott 
Published: August 2020

Background Comorbidity is of significant concern in multiple sclerosis (MS). Few population-based studies have reported conditions occurring in MS after diagnosis, especially in contemporary cohorts. Objective To explore incident comorbidity, mortality and hospitalizations in MS, stratified by age and sex. Methods In a Swedish population-based cohort study 6602 incident MS patients (aged ≥18 years) and 61,828 matched MS-free individuals were identified between 1 January 2008 and 31 December 2016, using national registers. Incidence rates (IRs) and incidence rate ratios (IRRs) with 95% CI were calculated for each outcome. Results IRs of cardiovascular disease (CVD) were higher among MS patients than MS-free individuals, (major adverse CVD: IRR 1.42; 95% CI 1.12–1.82; hemorrhagic/ischemic stroke: 1.46; 1.05–2.02; transient ischemic attack: 1.65; 1.09–2.50; heart failure: 1.55; 1.15–2.10); venous thromboembolism: 1.42; 1.14–1.77). MS patients also had higher risks of several non-CVDs such as autoimmune conditions (IRR 3.83; 3.01–4.87), bowel dysfunction (2.16; 1.86–2.50), depression (2.38; 2.11–2.68), and fractures (1.32; 1.19–1.47), as well as being hospitalized and to suffer from CVD-related deaths ((1.91; 1.00–3.65), particularly in females (3.57; 1.58–8.06)). Conclusion MS-patients experience a notable comorbidity burden which emphasizes the need for integrated disease management in order to improve patient care and long-term outcomes of MS.
Gene Expression in Meniscal Tears at the Time of Arthroscopic Partial Meniscectomy Predicts the Progression of Osteoarthritis Within 6 Years of Surgery
Authors: Lamplot Joseph D. , Rai Muhammad Farooq , Tompkins William P. , Friedman Michael V. , Schmidt Eric J. , Sandell Linda J. , Brophy Robert H. 
Published: August 2020

Background: While knees with meniscal tears are associated with a heightened risk of developing osteoarthritis (OA), it is difficult to predict which patients are at the greatest risk for OA. Gene signatures in menisci that are resected during arthroscopic partial meniscectomy (APM) may provide insight into the risk of OA progression. Hypothesis: Meniscal gene signatures at the time of APM will predict radiographic OA progression. Study Design: Case series; Level of evidence, 4. Methods: Meniscal fragments were collected from 38 patients without OA during clinically indicated APM of the medial meniscus. The expression of 28 candidate genes with known roles in cartilage homeostasis, OA, extracellular matrix degradation, and obesity was assessed by quantitative real-time polymerase chain reaction. Weightbearing radiographs obtained before surgery and at final follow-up were graded by a musculoskeletal radiologist using the Kellgren-Lawrence classification of OA. The association of meniscal gene expression at baseline with the progression of radiographic OA was determined. Results: Gene expression and baseline and follow-up radiographic data were available from 31 patients (81.6%) at a mean follow-up of 6.2 ± 1.3 years. Patients without OA progression had significantly higher expression of 7 genes: MMP9 (5.1-fold; P = .002), IL8 (2.9-fold; P = .016), CCL3 (3.7-fold; P = .032), CCL3L1 (4.5-fold; P = .008), CXCL6 (6.2-fold; P = .010), LEP (5.2-fold; P = .004), and RETN (46-fold; P = .008). Conclusion: Gene expression in the meniscus at the time of APM may be associated with the risk for progression of OA after surgery. Elevated expression of the aforementioned genes may reflect a chondroprotective response. Stratifying the risk for OA progression after APM could facilitate targeted interventions to delay or prevent the development of OA. Further studies in a larger cohort with an extended follow-up, and inclusion of additional genes, are warranted to better characterize this association.