Proteome changes in autosomal recessive primary microcephaly

Background/aim

: Autosomal recessive primary microcephaly (MCPH) is a rare and genetically heterogeneous group of disorders characterized by intellectual disability and microcephaly at birth, classically without further organ involvement. MCPH3 is caused by biallelic variants in the cyclin-dependent kinase 5 regulatory subunit-associated protein 2 gene CDK5RAP2. In the corresponding Cdk5rap2 mutant or Hertwig's anemia mouse model, congenital microcephaly as well as defects in the hematopoietic system, germ cells and eyes have been reported. The reduction in brain volume, particularly affecting gray matter, has been attributed mainly to disturbances in the proliferation and survival of early neuronal progenitors. In addition, defects in dendritic development and synaptogenesis exist that affect the excitation-inhibition balance. Here, we studied proteomic changes in cerebral cortices of Cdk5rap2 mutant mice.

Material and methods

: We used large-gel two-dimensional gel (2-DE) electrophoresis to separate cortical proteins. 2-DE gels were visualized by a trained observer on a light box. Spot changes were considered with respect to presence/absence, quantitative variation and altered mobility.

Result

: We identified a reduction in more than 30 proteins that play a role in processes such as cell cytoskeleton dynamics, cell cycle progression, ciliary functions and apoptosis. These proteome changes in the MCPH3 model can be associated with various functional and morphological alterations of the developing brain.

Conclusion

: Our results shed light on potential protein candidates for the disease-associated phenotype reported in MCPH3.     

Outcomes of cholecystectomy in US veterans with cirrhosis: Predicting outcomes using nomogram

BackgroundThis study examines the outcomes of open and laparoscopic cholecystectomy (OC/LC) in veterans with cirrhosis and develops a nomogram to predict outcomes.MethodsWe analyzed the Veterans Affairs Surgical Quality Improvement Program to identify all patients with cirrhosis and ascites who underwent cholecystectomy from 2008 to 2015. Univariate and multivariate regression were used to identify predictors of morbidity and mortality. A predictive nomogram was constructed and internally validated.ResultsA total of 349 patients were identified. Overall, complications occurred in 18.7% of patients, and mortality was 3.8%. LC was performed in 58.9%, and 19.2% were preformed emergently. Overall, Model for End-Stage Liver Disease score was an independent factor of morbidity and mortality, while laparoscopic approach had a protective effect on morbidity.ConclusionsAlthough cholecystectomy is a high-risk operation in cirrhotic veterans, LC may have favorable outcomes than OC in selected patients. An easy-to-use nomogram to predict morbidity and mortality for cirrhotic patients undergoing cholecystectomy is proposed.     

Iatrogenic esophageal perforation caused by endoscopic dilatation of caustic stricture: Current management and possibility of esophageal salvage

BackgroundIatrogenic esophageal perforation (EP) is an undesirable complication of endoscopic dilatation of caustic esophageal stricture. We reported our current management protocol with possibility of continuing the dilatation program.Patients and methodsFrom January 2009 to January 2020 medical records were reviewed for patients presented with iatrogenic EP. Management according to each case condition was reported.Results24 patients were enrolled, aged from 1.5 to 6 years old. Perforation was cervical in one case, abdominal in two cases, and thoracic in 21 cases. Immediate surgical repair was performed in the abdominal cases. Conservative management was chosen in 22 cases; two cases didn't respond and underwent esophageal diversion, and one of them died owing to severe sepsis. Three patients refused another trial of dilatation. Two cases failed to be redilated. 17 patients continued a dilatation program. Time passed between perforation and redilatation ranged from 35 days to 7 months. 15 patients were cured completely from dysphagia, one patient had marked improvement of his dysphagia, and one case with a resistant stricture was referred for esophageal replacement.ConclusionPreserving the native esophagus is possible after iatrogenic EP of caustic esophageal stricture. A conservative approach should be attempted with caution not to endanger patient's life.Level IV of evidence     

Postoperative outcomes of ventral hernia repair in veterans

BackgroundVentral hernia repair is a common procedure with reported 15% to 37% morbidity and 0.3% to 1.4% mortality rates. This study examines the 30-day morbidity and mortality of open and laparoscopic ventral hernia repair in veterans, along with the impact of body mass index on these outcomes.MethodsThe Veterans Affairs Surgical Quality Improvement Program was queried for all ventral hernia repairs during the period 2008 to 2015. In this retrospective analysis, we compared outcomes of open ventral hernia repair versus laparoscopic ventral hernia repair and among different body mass index classes.ResultsA total of 19,883 patients were identified (92.6% male, mean age 59.7, 53.1% obese, and 71.6% with American Society of Anesthesiologists class ≥III). There were 95 (0.5%) mortalities, and complications occurred in 1,289 (6.5%) patients. Open ventral hernia repair was performed in 60.2%; 14.5% were recurrent, and 3.3% were performed as an emergency operation. When compared with open ventral hernia repair, the laparoscopic ventral hernia repair group had higher mean body mass index, less patients with American Society of Anesthesiologists class ≥III, fewer emergency operations, longer operative time, less complications, decreased mortality, and shorter duration of stay. Body mass index 35.00 to 49.99 was predictive of overall complications in the open ventral hernia repair group.ConclusionVentral hernia repair can be performed in the veteran population with outcomes comparable to those in the private sector. Morbid obesity has a negative impact on ventral hernia repair outcomes that is most prominent following open surgery. Laparoscopic ventral hernia repair may offer superior outcomes when compared to open ventral hernia repair and may be considered.     

Pathological Assessment of the Response of Locally Advanced Breast Cancer to Neoadjuvant Chemotherapy and Its Implications for Surgical Management

(Received for publication on Sept. 8, 1998; accepted on Sept. 17, 1999)     

Corrosion Resistance and Surface Bioactivity of Ti6Al4V Alloy after Finish Turning under Ecological Cutting Conditions

The influence of cooling conditions and surface topography after finish turning of Ti6Al4V titanium alloy on corrosion resistance and surface bioactivity was analyzed. The samples were machined under dry and minimum quantity lubrication (MQL) conditions to obtain different surface roughness. The surface topographies of the processed samples were assessed and measured using an optical profilometer. The produced samples were subjected to electrochemical impedance spectroscopy (EIS) and corrosion potential tests (E_corr) in the presence of simulated body fluid (SBF). The surface bioactivity of the samples was assessed on the basis of images from scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) analysis. The inspection of the surfaces of samples after turning under dry and MQL conditions revealed unevenly distributed precipitation of hydroxyapatite compounds (Ca/P) with a molar ratio in the range of 1.73–1.97. Regardless of the cutting conditions and surface roughness, the highest values of E_corr ~0 mV were recorded on day 7 of immersion in the SBF solution. The impedance characteristics showed that, compared to the MQL conditions, surfaces machined under dry conditions were characterized by greater resistance and the presence of a passive layer on the processed surface. The main novelty of the paper is the study of the effect of ecological machining conditions, namely, dry and MQL cutting on the corrosion resistance and surface bioactivity of Ti6Al4V titanium alloy after finish turning. The obtained research results have practical significance. They can be used by engineers during the development of technological processes for medical devices made of Ti6Al4V alloy to obtain favorable functional properties of these devices.     

ASPECTS ÉPIDEMIOLOGIQUES ET THÉRAPEUTIQUES DES FRACTURES ACETABULAIRES CHEZ LE SUJET ÂGÉ

Introduction:

Management of acetabular fracture in the elderly patients is becoming an increasingly topic of debate. Data from different parts of the world specified particularities of their patients.

Aim:

To describe patterns of these fractures in the Tunisian patients aged > 60, which can contribute to management and preventive plans.

Methods:

We performed a retrospective review from 1997 to 2016 treated at the Charles Nicolle university hospital. Information regarding demographics, co morbidities, mechanism of injury, Injury Severity Score (ISS), types and levels of injury, treatment type, and mortality were collected.

Results:

The mean age of our patients was 68,6 years (range 60–94 years). The male to female ratio was 3:85.Main causes were motor vehicle accident. Most of our patients were in good health. The associated lesions were very frequent and present in 64.7% of cases with a clear predominance of cranio-fascial trauma, with a median of the ISS score at 11. According to the Judet and Letournel classification, 18 elementary fractures and 16 complex fractures were reported with predominance of the anterior column-posterior hemitransverse fracture pattern. Posterior wall fracture in the elderly is often associated with comminution and / or marginal impaction and / or posterior dislocation of the hip. Fractures of the anterior segment are often associated with hip protrusion and / or quadrilateral plate involvement and / or the superomedial roof impaction or "Gull sign".

Conclusion:

As our population continues to age, traumatic acetabular fractures will become more prevalent. Appropriate screening strategies, treatment and prevention plans will need to be developed to improve outcomes in this devastating injury.     

Effect of silylating agents on the superhydrophobic and self-cleaning properties of siloxane/polydimethylsiloxane nanocomposite coatings on cellulosic fabric filters for oil–water separation

A new facile approach for preparing two nonfluorinated hybrid organic–inorganic siloxane/polydimethylsiloxane nanocomposite coatings for cotton fabrics is presented using two distinct silylating agents. The first coated fabric was prepared predominantly via trimethylsilyl modification using hexamethyldisilazane (HMDS) while higher amounts of trimethoxy(octadecyl)silane (TMOS) further enhanced the superhydrophobicity of the second coating matrix. Unlike HMDS with substituted silyl (Me₃Si) groups, TMOS consists of hydrolysable trimethoxy silyl ((MeO)₃Si) chemical groups that allowed for the formation of nanosilica with Si–O–Si linkages needed to foster stable coatings. After characterization and testing, these coated fabrics demonstrated varying responses to harsh solvents and thermal conditions. Both sets of coated fabrics exhibited unique capacities for self-cleaning and oil–water separation as superhydrophobic filters due to (a) their low surface energy silylated hybrid polysiloxane chemical groups, (b) their highly reduced surface wettability and (c) nanopatterned surface morphologies. In this study, coated superhydrophobic cotton fabrics revealed a higher static aqueous contact angle of more than 150° and sliding hysteresis angle of less than 5°. Coated fabrics with 30 mg TMOS/10 mg HMDS (CMF3) and 30 mg HMDS/10 mg TMOS (CTF3) exhibited optimal superhydrophobicity. Both fabrics also retained percentage separation efficiencies over 90% for both chloroform–water and toluene–water mixtures. However, CTF3 displayed with a recorded separation efficiency less than 90° after five filtration cycles.

Two silylating agents, hexamethyldisilazane and trimethoxy(octadecyl)silane enhance the superhydrophobicity and self-cleaning properties of siloxane/PDMS nanocomposite coatings on cotton filters for oil–water separation.     

Effect of a Nanostructured Titanium Surface on Gingival Cell Adhesion,Viability and Properties against P. gingivalis

Objectives: The transgingival part of titanium implants is either machined or polished. Cell-surface interactions as a result of nano-modified surfaces could help gingival fibroblast adhesion and support antibacterial properties by means of the physico-mechanical aspects of the surfaces. The aim of the present study was to determine how a nanocavity titanium surface affects the viability and adhesion of human gingival fibroblasts (HGF-1). Additionally, its properties against Porphyromonas gingivalis were tested. Material and Methods: Two different specimens were evaluated: commercially available machined titanium discs (MD) and nanostructured discs (ND). To obtain ND, machined titanium discs with a diameter of 15 mm were etched with a 1:1 mixture of 98% H₂SO₄ and 30% H₂O₂ (piranha etching) for 5 h at room temperature. Surface topography characterization was performed via scanning electron microscopy (SEM) and atomic force microscopy (AFM). Samples were exposed to HGF-1 to assess the effect on cell viability and adhesion, which were compared between the two groups by means of MTT assay, immunofluorescence and flow cytometry. After incubation with P. gingivalis, antibacterial properties of MD and ND were determined by conventional culturing, live/dead staining and SEM. Results: The present study successfully created a nanostructured surface on commercially available machined titanium discs. The etching process created cavities with a 10–20 nm edge-to-edge diameter. MD and ND show similar adhesion forces equal to about 10–30 nN. The achieved nanostructuration reduced the cell alignment along machining structures and did not negatively affect the proliferation of gingival fibroblasts when compared to MD. No differences in the expression levels of both actin and vinculin proteins, after incubation on MD or ND, were observed. However, the novel ND surface failed to show antibacterial effects against P. gingivalis. Conclusion: Antibacterial effects against P. gingivalis cannot be achieved with nanocavities within a range of 10–20 nm and based on the piranha etching procedure. The proliferation of HGF-1 and the expression levels and localization of the structural proteins actin and vinculin were not influenced by the surface nanostructuration. Further studies on the strength of the gingival cell adhesion should be performed in the future. Clinical relevance: Since osseointegration is well investigated, mucointegration is an important part of future research and developments. Little is known about how nanostructures on the machined transgingival part of an implant could possibly influence the surrounding tissue. Targeting titanium surfaces with improved antimicrobial properties requires extensive preclinical basic research to gain clinical relevance.     

Prediction of emulsification behaviour of pea and faba bean protein concentrates and isolates from structure–functionality analysis

The effects of different extraction methods on the structure–functionality and emulsification behaviour of pea and faba bean protein isolates, and concentrates were studied at pH 7 and 2, and a regression model was developed to predict emulsion characteristics based on protein properties. The concentrates produced by air classification had lower protein content but higher solubility in water compared to the isolates produced by isoelectric precipitation. The protein secondary structure did not show a consistent difference; however, much higher intrinsic fluorescence was observed for the soluble compared to the insoluble fractions. Interfacial tension of all faba proteins was lower than pea, while there was no significant difference between the concentrates and isolates. The higher protein content of the isolates was found to improve their water holding capacity. Canola oil (40 wt%)-in-water coarse emulsions, prepared with 2 wt% proteins and 0.25 wt% xanthan gum showed smaller particle size at pH 7 than pH 2, while the zeta potential, viscosity and gel strength were higher at pH 7. Emulsions stabilized with concentrates were better or comparable to the isolates in terms of particle size, zeta potential, and microstructure. The regression model predicted that an increase in solubility, intrinsic fluorescence, water and oil holding capacities are more favourable to decrease emulsion particle size, while an increase in solubility, intrinsic fluorescence would lead to higher emulsion destabilization. A decrease in interfacial tension was more favourable to lower destabilization. Emulsion viscosity was more dependent on water holding capacity compared to any other factor. Such models could be extremely beneficial for the food industry to modulate processing for the development of desired pulse protein ingredients.

The effects of different extraction methods on the structure–functionality and emulsification behaviour of pea and faba bean proteins were studied, and a regression model was developed to predict emulsion characteristics based on protein properties.