Graphene materials as 2D non-viral gene transfer vector platforms

Advances in genomics and gene therapy could offer solutions to many diseases that remain incurable today, however, one of the critical reasons halting clinical progress is due to the difficulty in designing efficient and safe delivery vectors for the appropriate genetic cargo. Safety and large-scale production concerns counter-balance the high gene transfer efficiency achieved with viral vectors, while non-viral strategies have yet to become sufficiently efficient. The extraordinary physicochemical, optical and photothermal properties of graphene-based materials (GBMs) could offer two-dimensional components for the design of nucleic acid carrier systems. We discuss here such properties and their implications for the optimization of gene delivery. While the design of such vectors is still in its infancy, we provide here an exhaustive and up-to-date analysis of the studies that have explored GBMs as gene transfer vectors, focusing on the functionalization strategies followed to improve vector performance and on the biological effects attained.

Enhanced Interictal Responsiveness of the Migraineous Visual Cortex to Incongruent Bar Stimulation: A Functional MRI Visual Activation Study

Since visual aura is usually described as expanding zigzag lines, neurones involved with the perception of line orientation may initiate this phenomenon. A visual incongruent line stimulation protocol was developed to obtain functional magnetic resonance images (fMRI) interictally in 5 female migraine patients with typical fortification spectra and in 5 normal matched controls. Activation in the visual cortex was present contralateral to the side of stimulation in 4 of 5 patients, notably in the extrastriate visual cortex. In 4 of 5 controls activation was observed in the medial and anterior orbitofrontal cortex. In one of them additional activation at the right nucleus accumbens/ventral striatum and right ventral pallidum was present. In the remaining control subject activation was present in the left primary visual cortex. The enhanced interictal reactivity of the visual cortex in migraineurs supports the hypothesis of abnormal cortical excitability as an important pathophysiological mechanism in migraine aura, though the role of specific regions of the visual cortex remains to be explored.

Polishing surgical metal pieces, granulomatosis and mineralogical analysis

This report describes the case of a 44-year-old man with pulmonary nodules whose histological analysis initially suggested tuberculosis. The Mycobacterium tuberculosis (MT) culture was negative and a questionnaire revealed a professional activity of brushing and polishing surgical instruments without any protection for 7 years.  A mineralogical analysis by optical and electron microscopy was performed on both a healthy lung tissue biopsy and a lung nodule in a paraffin block. Electron microscopy analysis revealed the presence of metal particles (iron oxide, titanium oxide, aluminum oxide and steel) in both samples. This study suggests that mineralogical analysis combined with a questionnaire on dust exposure could help redirect the diagnosis of a dust-related disease.

Numerical Modeling of Bubble Growth in Microcellular Polypropylene Produced in a Core-Back Injection Process Using Chemical Blowing Agents

A core-back polypropylene foaming injection process using chemical blowing agents (CBA) has been studied. First, injection tests were carried out with two different CBAs and the different morphologies of the obtained samples have been analyzed. Structural parameters such as cell density and average radius size were calculated. Then, a bubble growth model was developed to predict the foaming development during the process, controlled by the depressurization of the mold cavity during the short core-back opening coupled with the evolution of the temperature during core-back and subsequent cooling. A good agreement is found between theoretical predictions and experimental results.

Relationship of glycaemic control and hypoglycaemic episodes to 4-year cardiovascular outcomes in people with type 2 diabetes starting insulin

AIMS

To examine the relationships between glycated haemoglobin (HbA1c) and cardiovascular (CV) events in people beginning insulin in routine clinical practice in Europe, North America and Asia in a non-interventional study, the Cardiovascular Risk Evaluation in people with Type 2 Diabetes on Insulin Therapy (CREDIT) study.

METHODS

Data on 2999 people were collected prospectively over 4 years from physician reports. The primary outcome was the composite of stroke or myocardial infarction (MI) or CV-specific death. Events were blindly adjudicated. The relative hazards of CV events were described from Cox proportional hazards models incorporating patient risk factors, with updated average HbA1c as a time-dependent covariate. The relationship of severe and symptomatic hypoglycaemia (collected during the 6 months before yearly ascertainment) with CV and all-cause mortality was examined.

RESULTS

A total of 147 primary events were accrued during up to 54 months of follow-up. In all, 60 CV-specific deaths, 44 non-fatal MIs and 57 non-fatal strokes occurred, totalling 161 events. There was a significant positive relationship between updated mean HbA1c and primary outcome: hazard ratio (HR) 1.25 [95% confidence interval (CI) 1.12-1.40; p < 0.0001]. CV death [HR 1.31 (95% CI 1.10-1.57); p = 0.0027] and stroke [HR 1.36 (95% CI 1.17-1.59); p < 0.0001] were both strongly associated with HbA1c, while MI was not [HR 1.05 (95% CI 0.83-1.32)]. One or more severe hypoglycaemic episodes affected 175 participants, while 1508 participants experienced one or more symptomatic hypoglycaemic events. We found no relationship between severe/symptomatic hypoglycaemic events and CV-specific/all-cause death.

CONCLUSIONS

Ongoing poorer glucose control was associated with CV events; hypoglycaemia was not associated with CV-specific/all-cause death.

Electrofusion Welding Process Optimization Using a Coupled Numerical and Experimental Approach

In the water and gas distribution industry, electrofusion is one of the main techniques used for welding polyethylene pipes. In order to help understanding the origin of some defects discovered recently and to optimize and predict the welding quality, we developed a coupled numerical and experimental approach. Our numerical model, that computes a weld quality index based on molecular interdiffusion, is able to reasonably well predict whether welding will occur or not depending on the welding conditions imposed.

[Foreign body of dental origin: How to retrieve the dentist's drill?]

INTRODUCTION

Inhalation of foreign bodies is an unusual complication of dental care. When it occurs immediately during the intervention, it is generally a dental tool, such as the little screwdrivers used for dental implant procedures.

CASE REPORT

A 59-year-old man was referred to our hospital for asymptomatic inhalation of a small drill during dental surgery. Because the drill had a barbed tip, prompt removal was indicated. The foreign body was localized in a sub-segmental division of the left lower lobe (B10b) and could be removed via a flexible bronchoscope under a short general anesthetic without intubation. There was no significant injury of the bronchial mucosa.

CONCLUSION

Inhalation of foreign bodies during dental interventions is unusual and sometimes asymptomatic but their removal is always indicated. In some cases, the removal can be performed with a flexible bronchoscope.

Isolated and syndromic brachydactylies: Diagnostic value of hand X-rays

Brachydactyly, or shortening of the digits, is due to the abnormal development of phalanges, metacarpals and/or metatarsals. This congenital malformation is common, easily detectable clinically but often requires additional radiological exploration. Radiographs are essential to characterize the type of brachydactyly and to show the location of the bone shortening, as well as any associated malformation. This article reviews the radiological findings for isolated brachydactylies (according to the types classified by Bell, and Temtamy and McKusick) and for brachydactylies that are part of complex multisystem malformation syndromes. If warranted by the clinical and radiological examinations, a genetic analysis (molecular and/or cytogenetic) can confirm the etiologic diagnosis.

Comparison of insulin glargine and liraglutide added to oral agents in patients with poorly controlled type 2 diabetes

AIM

To compare safety and efficacy of insulin glargine and liraglutide in patients with type 2 diabetes (T2DM).

METHODS

This randomized, multinational, open-label trial included subjects treated for T2DM with metformin ± sulphonylurea, who had glycated haemoglobin (HbA1c) levels of 7.5-12%. Subjects were assigned to 24 weeks of insulin glargine, titrated to target fasting plasma glucose of 4.0-5.5 mmol/L or liraglutide, escalated to the highest approved clinical dose of 1.8 mg daily. The trial was powered to detect superiority of glargine over liraglutide in percentage of people reaching HbA1c <7%.

RESULTS

The mean [standard deviation (s.d.)] age of the participants was 57 (9) years, the duration of diabetes was 9 (6) years, body mass index was 31.9 (4.2) kg/m(2) and HbA1c level was 9.0 (1.1)%. Equal numbers (n = 489) were allocated to glargine and liraglutide. Similar numbers of subjects in both groups attained an HbA1c level of <7% (48.4 vs. 45.9%); therefore, superiority of glargine over liraglutide was not observed (p = 0.44). Subjects treated with glargine had greater reductions of HbA1c [-1.94% (0.05) and -1.79% (0.05); p = 0.019] and fasting plasma glucose [6.2 (1.6) and 7.9 (2.2) mmol/L; p < 0.001] than those receiving liraglutide. The liraglutide group reported a greater number of gastrointestinal treatment-emergent adverse events (p < 0.001). The mean (s.d.) weight change was +2.0 (4.0) kg for glargine and -3.0 (3.6) kg for liraglutide (p < 0.001). Symptomatic hypoglycaemia was more common with glargine (p < 0.001). A greater number of subjects in the liraglutide arm withdrew as a result of adverse events (p < 0.001).

CONCLUSION

Adding either insulin glargine or liraglutide to subjects with poorly controlled T2DM reduces HbA1c substantially, with nearly half of subjects reaching target levels of 7%.

METABOLIC EFFECTS OF MARIJUANA USE AMONG BLACKS

BACKGROUND

Increased legalization of marijuana has resulted in renewed interest in its effects on body weight and cardiometabolic risk. Conflicting data exist regarding marijuana effects on body weight, waist circumference as well as lipid profiles, blood pressure and cardiovascular disease. Furthermore, there is a dearth of data available on this effect in the black population.

OBJECTIVE

To assess the metabolic profile and cardiovascular risk factors as well as body weight and waist circumference among urban black marijuana users.

METHODS

A cross sectional study design involving 100 patients seen in a Family Practice clinic at University hospital of Brooklyn, NY, USA, over a period of 3 months from January 2014 to March 2014. Participants were administered a questionnaire regarding marijuana use, and other associated behaviors. Socio-demographic, laboratory, and clinical data were collected. We report measures of central tendencies, and dispersion for continuous variables and the frequency of distribution for categorical variables.

RESULTS

Of the 100 patients surveyed, 57% were females. The mean (±SEM) age of the entire cohort was 46.3 years±1.5; range, 19-78 years. The mean body mass index (BMI) was 29.6 kg/m2±0.73; SBP=128.0 mmHg±1.69; DBP=76.1 mmHg±1.17. Current marijuana users had the lowest waist circumference compared to former or never users respectively (32.9±0.66 vs. 35.9±0.88 vs. 33.4±0.74), p<0.01. Diastolic blood pressure in mmHg was significantly higher among former marijuana users compared to current or never users, (80.0±2.1 vs. 73.3±2.3 vs. 73.4±1.6), p<0.01. Current marijuana users showed a tendency (not statistically significant) towards lower total cholesterol, Triglycerides (TG), High Density Lipoprotein (HDL)-cholesterol, Low Density Lipoprotein (LDL)-cholesterol, body mass index (BMI) and systolic blood pressure, compared to former users or never users.

CONCLUSION

Current marijuana use is associated with significantly lower waist circumference, compared to former users and never users. Except for diastolic BP that was significantly lower among current users, other metabolic parameters showed tendency towards favorable profile. Further studies are needed to characterize the metabolic effects and to elucidate mechanisms of actions of marijuana in view of its rapid rate of utilization in the USA and around the world.

Global, multicenter, randomized, phase II trial of gemcitabine and gemcitabine plus AGS-1C4D4 in patients with previously untreated, metastatic pancreatic cancer

BACKGROUND

We evaluated AGS-1C4D4, a fully human monoclonal antibody to prostate stem cell antigen (PSCA), with gemcitabine in a randomized, phase II study of metastatic pancreatic cancer.

PATIENTS AND METHODS

Patients with Eastern Cooperative Oncology Group (ECOG) performance status 0/1 and previously untreated, metastatic pancreatic adenocarcinoma were randomly assigned 1:2 to gemcitabine (1000 mg/m(2) weekly seven times, 1 week rest, weekly three times q4weeks) or gemcitabine plus AGS-1C4D4 (48 mg/kg loading dose, then 24 mg/kg q3weeks IV). The primary end point was 6-month survival rate (SR). Archived tumor samples were collected for pre-planned analyses by PSCA expression.

RESULTS

Between April 2009 and May 2010, 196 patients were randomly assigned to gemcitabine (n = 63) or gemcitabine plus AGS-1C4D4 (n = 133). The 6-month SR was 44.4% (95% CI, 31.9-57.5) in the gemcitabine arm and 60.9% (95% CI, 52.1-69.2) in the gemcitabine plus AGS-1C4D4 arm (P = 0.03), while the median survival was 5.5 versus 7.6 months and the response rate was 13.1% versus 21.6% in the two arms, respectively. The 6-month SR was 57.1% in the gemcitabine arm versus 79.5% in the gemcitabine plus AGS-1C4D4 arm among the PSCA-positive subgroup and 31.6% versus 46.2% among the PSCA-negative subgroup.

CONCLUSIONS

This randomized, phase II study achieved its primary end point, demonstrating an improved 6-month SR with addition of AGS-1C4D4 to gemcitabine among patients with previously untreated, metastatic pancreatic adenocarcinoma. ClinicalTrials.gov identifier: NCT00902291.

Injection Moulding of Rubber Compounds1

The aim of this study is to show the relevant physical parameters related to rubber injection moulding, and especially compressibility, vulcanisation and wall slippage. Three materials are studied: an SBR compound, without and with a lubricant, and an EPDM compound. The viscosity is determined by capillary rheometry. The modified SBR exhibits wall slippage. Rheological vulcanisation kinetics are determined with a Moving Die Rheometer. Precise moulding experiments are carried out with an injection moulding machine and a mould equipped with pressure and temperature transducers. At low flow rate, the influence of the curing reaction on the pressure appears clearly especially for the fast curing EPDM. The conditions in which surface scorch defects appear are determined. The SBR with lubricant needs a lower pressure to fill the cavity than without lubircant. A model of mould filling is developed. The material is purely viscous, with a state of cure dependence of the viscosity. A Norton friction law is introduced to take into account a possible slippage at the cavity walls. A compressible calculation in the injection chamber allows a realistic evaluation of the flow rate at the entry of the cavity. The comparison with the experimental data confirms the importance of the compressibility, and the influence of the vulcanisation on the viscosity at low flow rate. In moulding conditions for which vulcanisation is not activated during the filling stage, despite uncertainties on the friction law parameters appropriate to the cavity wall roughness, the agreement with experiments is better when wall slippage is taken into account.

Elastic Calculation of Residual Stresses in Injection Molding

A calculation of residual stresses in injection molding using a 2-D description of the geometry is presented. The polymer follows an elastic behavior law. The thermal shrinkage and the frozen-in pressure when a layer solidifies are taken into account. A calculation of the pressure in the liquid areas after the gate is frozen is presented. A simplified mold deformation model is introduced and its influence on residual stresses is shown. Results are presented for a polystyrene injected in a square plaque.

Injection Molding of Reinforced Thermosets

The orientation of glass fibers (initial length 20 mm) and the mold filling of reinforced unsaturated polyester compounds have been studied. Observations of the fiber orientation have been made in three molds where shear and elongational flows occur in variable ways. A part of the fibers are split and broken into filaments. Reinforcement can be more or less buckled. A thin skin layer without fibers is observed. The great thickness of a core region with an orientation perpendicular to the flow direction shows the importance of negative elongational flows. Efficiency of positive elongational flows to suppress buckling and to give a well flow aligned orientation is also observed. On the contrary the efficiency of shear flows is limited compared to elongational flows. The incidence of injection conditions on the pressure inside a rectangular plaque has been studied both experimentally and theoretically. Experimental difficulties due to the material heterogeneity leads to measure viscosity data of the uncured material on a special capillary rheometer and rheological kinetic data on a simplified compound. Numerical results are in good agreement with experimental measurements. For instance the effect of crosslinking which leads to a pressure rise at low flow rate or high mold temperature is well predicted.

Flow and Fiber Orientation Calculations in Reinforced Thermoplastic Extruded Tubes

A calculation of fiber orientation of reinforced thermoplastics in two tube die geometries is presented. The flow field and fiber motion are calculated using coupled anisotropic constitutive equation and equation of change for fiber orientation. A finite element method is used for the flow field computation, and a simplified characteristic method for the fiber orientation. Results show that fibers orient parallel to the tube axis in a classical die of constant radius in the final land whereas fibers have a more isotropic orientation in a die with a final divergent land. Experimental observations and quantification of fiber orientation in reinforced thermoplastic tubes extruded with the two dies are presented. Results of the calculation agree well with the experimental data for the classical die. For the diverging die, the agreement is good at the tube surface, but the calculation underestimates the degree of orientation perpendicular to the tube axis in the core of the tube.

External Calibration in PA12 Tube Extrusion

Elongation at break is one of the major end-use properties of polyamide 12 extruded tubes. It is strongly affected by the tube microstructure and the molecular orientation resulting from extrusion conditions. Molecular orientation was characterized by X-ray diffraction and birefringence evaluation in light microscopy. Measurements were carried out on (r, z) sections obtained by polishing and microtoming. On the other hand, polymer drawing was measured on line by tracer techniques. Calibration stage was determined as the key step of the process that generates orientation in tubes: as the tube is drawn through a cylindrical calibrator under vacuum and cooled from its outside surface, calibration leads to a highly oriented zone in the twenty external microns. Calibration conditions and elongation at break have been connected through orientation level in this region. Molecular orientation was found to strongly depend on the draw ratio in the calibration tank. Finally, birefringence of the tube external layers and elongation at break were successfully correlated. Elongation at break can be enhanced by reducing orientation resulting from calibration conditions.

External Calibration in PA12 Tube Extrusion

In PA12 tube extrusion, calibration or sizing is the key step of the process that affects subsequent mechanical properties. The extruded tube is pulled through a cylindrical calibrator under vacuum. A water flow rate is applied at the inner side of the calibrator, creating a lubricant water layer at the polymer outer surface. The scope of this article is to show how this lubrication influences the elongation at break of tubes through drawing kinematics of the polymer. Lubricant water layer thickness measurements and on-line video recording have been employed to monitor the lubrication dependence of the velocity profiles from the extruder die to the end of calibrator. Velocities were measured through three independent innovative methods and thirty-two calibration conditions have been carried out to validate our work. Three main calibration parameters were found to determine the water layer thickness: the level of vacuum applied in the calibration tank, the water flow rate at the calibrator entrance, and the line speed. The influence of each parameter on lubrication level was found out. Simultaneously, the draw ratio in the calibration tank was deduced from velocity profiles. This parameter was found to affect tensile properties and to depend strongly on the level of lubrication during calibration. We showed quantitatively that rising the water layer thickness leads to a diminution of the draw ratio in the calibration tank and an increase of the elongation at break. This implies that we are now able to optimize tensile properties by fitting the main calibration parameters to improve lubrication and restrict draw ratio in the calibration tank.

Treatment of diabetic ketoacidosis with subcutaneous insulin lispro: a review of the current evidence from clinical studies

AIM

Low-dose intravenous infusions of regular insulin, usually initiated in the emergency department and continued in the intensive care unit (ICU), are the standard care for patients with diabetic ketoacidosis (DKA) to ensure rapid resolution of hyperglycaemia and ketoacidosis. Several studies have evaluated whether subcutaneous injections of the rapid-acting analogue insulin lispro may be an alternative to intravenous insulin infusion for avoiding ICU admissions of uncomplicated DKA cases.

METHODS

This review summarizes the current clinical evidence for the effectiveness and safety of subcutaneous insulin lispro injections in non-severe DKA patients. Relevant studies were identified by a systematic literature search through the PubMed database.

RESULTS

To date, four small randomized studies (156 patients overall; three studies in adults and one in paediatric patients with diabetes) have directly compared subcutaneous insulin lispro injections every 1-2h vs continuous intravenous infusions of regular insulin. Patients with severe complications were excluded. In all studies, the mean time to resolution of DKA was similar in both treatment groups [range (three studies): lispro 10-14.8h; regular insulin 11-13.2h]. The mean time to resolution of hyperglycaemia, total insulin doses required, number of hospitalization days and number of hypoglycaemic episodes were similar in both treatment groups; no severe complications or DKA recurrences were reported, and one study showed a 39% cost reduction for the insulin lispro group.

CONCLUSION

In patients with mild-to-moderate DKA, subcutaneous injections of insulin lispro every 1-2h offer a feasible alternative to continuous intravenous infusions of regular insulin, and should now be evaluated in larger, more appropriately powered studies.