SciCombinator

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Processing and manipulation of highly conductive pristine graphene in large quantities are still major challenges in the practical application of graphene for electric device. In the present study, we report the liquid-phase exfoliation of graphite in toluene using well-defined poly(3-hexylthiophene) (P3HT) to produce a P3HT/graphene composite. We synthesize and use regioregular P3HT with controlled molecular weights as conductive dispersants for graphene. Simple ultrasonication of graphite flakes with the P3HT successfully produces single-layer and few-layer graphene sheets dispersed in toluene. The produced P3HT/graphene composite can be used as conductive graphene ink, indicating that the P3HT/graphene composite has high electrical conductivity owing to the high conductivity of P3HT and graphene. The P3HT/graphene composite also works as an oxidation-resistant and conductive film for a copper substrate, which is due to the high gas-barrier property of graphene.

Concepts: Electricity, Electrical conductor, Aluminium, Copper, Graphite, Graphene, Electrical conductivity, Fullerene

23

Dogs with a 4-bp deletion in the MDR1 (or ABCB1) gene show intolerance to certain drugs routinely used in veterinary medicine, such as ivermectin, vincristine, and doxorubicin. The mutation leads to a dysfunctional P-glycoprotein drug transporter, which results in drug accumulation in the brain and severe neurotoxicity. A rapid and accurate in-house test to determine the genotype of patients in cases of acute neurotoxic signs or in tumor patients is desirable. We describe a cost-effective detection method with simple technical equipment for veterinary practice. Two allele-specific methods are presented, which allow discrimination of all genotypes, require little hands-on time, and show the results within ~1 h after DNA sampling. DNA from buccal swabs of 115 dogs with known genotype (no mutation, n = 54; heterozygous for the mutation, n = 37; homozygous for the mutation, n = 24) was extracted either by using a column-based extraction kit or by heating swabs in a simple NaOH-Tris buffer. Amplification was performed either by allele-specific fast polymerase chain reaction or by allele-specific loop-mediated isothermal amplification (LAMP). Analysis was done either on agarose gels, by simple endpoint visualization using ultraviolet light, or by measuring the increase of fluorescence and time to threshold crossing. Commercial master mixes reduced the preparation time and minimized sources of error in both methods. Both methods allowed the discrimination of all 3 genotypes, and the results of the new methods matched the results of the previous genotyping. The presented methods could be used for fast individual MDR1/ ABCB1 genotyping with less equipment than existing methods.

Concepts: DNA, Genetics, Ultraviolet, Evolution, Polymerase chain reaction, Molecular biology, Zygosity, Agarose gel electrophoresis

18

 To assess diagnostic accuracy of screening tests for pre-diabetes and efficacy of interventions (lifestyle or metformin) in preventing onset of type 2 diabetes in people with pre-diabetes.

Concepts: Insulin, Diabetes mellitus type 2, Evaluation, Obesity, Diabetes, Insulin resistance, Sulfonylurea, Prevention

8

 To quantify the cost effectiveness of a government policy combining targeted industry agreements and public education to reduce sodium intake in 183 countries worldwide.

Concepts: Policy, Government, Nation, Sovereign state

0

Individuals infected with Mycobacterium tuberculosis (Mtb) may develop symptoms and signs of disease (tuberculosis disease) or may have no clinical evidence of disease (latent tuberculosis infection [LTBI]). Tuberculosis disease is a leading cause of infectious disease morbidity and mortality worldwide, yet many questions related to its diagnosis remain.

Concepts: Epidemiology, Disease, Infectious disease, Medical terms, Infection, Symptom, Tuberculosis, Latent tuberculosis

0

Despite an ageing Fontan population, data on late outcomes are still scarce. Reported outcome measures and determinants vary greatly between studies making comprehensive appraisal of mortality hazard challenging.

Concepts: Population, Outcome

0

OBJECTIVE To evaluate eicosanoid concentrations in freshly prepared canine packed RBCs (PRBCs) and to assess changes in eicosanoid concentrations in PRBC units over time during storage and under transfusion conditions. DESIGN Prospective study. SAMPLE 25 plasma samples from 14 healthy Greyhounds. PROCEDURES Plasma samples were obtained during PRBC preparation (donation samples), and the PRBC units were then stored at 4°C until used for transfusion (≤ 21 days later; n = 17) or mock transfusion if expired (22 to 24 days later; 8). Immediately prior to use, 100 mL of saline (0.9% NaCl) solution was added to each unit and a pretransfusion sample was collected. A posttransfusion sample was collected after transfusion or mock transfusion. Concentrations of arachidonic acid, prostaglandin (PG) F2α, PGE2, PGD2, thromboxane B2, 6-keto-PGF1α, and leukotriene B4 were measured by liquid chromatography-mass spectrometry and analyzed statistically. RESULTS Median arachidonic acid concentration was significantly decreased in posttransfusion samples, compared with the concentration in donation samples. Median PGF2α, 6-keto-PGF1α, and leukotriene B4 concentrations were significantly increased in pretransfusion samples, compared with those in donation samples. Median PGF2α, thromboxane B2, and 6-keto-PGF1α concentrations were significantly increased in posttransfusion samples, compared with those in pretransfusion samples. Duration of PRBC storage had significant associations with pretransfusion and posttransfusion arachidonic acid and thromboxane B2 concentrations. CONCLUSIONS AND CLINICAL RELEVANCE Concentrations of several proinflammatory eicosanoids increased in PRBC units during storage, transfusion, or both. Accumulation of these products could potentially contribute to adverse transfusion reactions, and investigation of the potential association between eicosanoid concentrations in PRBCs and the incidence of transfusion reactions in dogs is warranted.

Concepts: Inflammation, Red blood cell, Prostacyclin, Eicosanoid, Prostaglandin, Leukotriene, Arachidonic acid, Eicosanoids

0

OBJECTIVE To describe the learning curve for veterinary surgery residents performing hemilaminectomy surgeries in dogs. DESIGN Retrospective case review and learning curve evaluation. SAMPLE 13 individuals who completed a 3-year surgery residency program at a university teaching hospital and who had no prior experience performing hemilaminectomies. PROCEDURES The 13 residents performed hemilaminectomies on 399 dogs between July 2006 and July 2013. Medical records were reviewed, and operative time was recorded. Data were examined with a linear mixed-effects model to quantify fixed and random effects, a curve-fitting technique to find the best-fit curve, and a segmented 2-phase linear model to describe the domains and learning rates for 2 phases of learning. RESULTS The linear mixed-effects model indicated that increasing patient body weight and increasing surgical complexity (graded on the basis of number and contiguity of hemilaminectomy sites) were associated with longer operative times and that increasing exposure number was associated with shorter operative times. The monoexponential and biexponential parametric curves were of similar quality in modeling the data. The segmented 2-phase linear model showed an early phase of learning during which operative time decreased rapidly and a late phase when operative time decreased more gradually. CONCLUSIONS AND CLINICAL RELEVANCE The learning curve for the residents suggested that for early exposures, instruction in the form of direct supervision provided substantial benefit. By the tenth exposure, the benefit of instruction diminished and ongoing improvement was primarily a result of refinement. If validated by further study, this understanding of a 2-phase learning curve may inform the design of training programs in veterinary surgery.

Concepts: Time, Medicine, Hospital, Surgery, Physician, Learning curve, Veterinarian, Parametric equation

0

CASE DESCRIPTION A 6-year-old spayed female Great Pyrenees (dog 1) and a 2-year-old spayed female German Shepherd Dog (dog 2) were evaluated because of gross hematuria of 5 and 2 months' duration, respectively. CLINICAL FINDINGS In both dogs, coagulation times were within reference limits, results of aerobic bacterial culture of urine samples were negative, echogenic debris could be seen within the urinary bladder ultrasonographically, and hematuric urine could be seen exiting the right ureterovesicular junction, with grossly normal urine exiting the left ureterovesicular junction, during cystoscopy. A diagnosis of idiopathic renal hematuria was made in both dogs. TREATMENT AND OUTCOME Both dogs underwent retrograde ureteropyelography, unilateral povidone iodine sclerotherapy, and ureteral stent placement. The right ureter was occluded with a ureteropelvic junction balloon catheter, and a 5% povidone iodine solution was infused into the renal pelvis 3 times. A double-pigtail ureteral stent was then placed. Both dogs recovered without complications, with cessation of gross hematuria within 12 hours. Cystoscopic removal of the ureteral stent was performed in dog 1 after 4 months; at that time, the urine sediment contained 5 to 10 RBCs/hpf. In dog 2, urine sediment contained 50 to 75 RBCs/hpf 2 weeks after sclerotherapy, with continued resolution of gross hematuria 8 weeks after sclerotherapy. The owners declined removal of the stent in dog 2. CLINICAL RELEVANCE Findings suggested that povidone iodine sclerotherapy may be an effective renal-sparing treatment for idiopathic renal hematuria in dogs. Further evaluation with longer follow-up times is warranted.

Concepts: Kidney, Urine, Urinary bladder, Urinary system, Ureter, Renal pelvis, Hematuria, Povidone-iodine

0

CASE DESCRIPTION A 15-year-old neutered male domestic shorthair cat was examined for treatment of a recurrent neoplastic mass in the left upper eyelid that had been excised 6 months earlier by the referring veterinarian. CLINICAL FINDINGS An apparently nonpainful firm cutaneous mass (approx 2 × 2 mm) was located on the lateral third of the left upper eyelid near the scar from the previous surgical excision. TREATMENT AND OUTCOME Approximately one-third of the left upper lip was used as a subdermal plexus (lip-to-lid) flap to cover the defect created by en bloc excision of the eyelid mass. A bridge incision between the donor and recipient sites was used so that the eyelid could be reconstructed in 1 procedure. Histologic evaluation confirmed that the mass had been completely excised. Both the donor and recipient flap sites healed well without complications. The procedure resulted in excellent functional and cosmetic results with no recurrence of the mass at 14 months after surgery. CLINICAL RELEVANCE The described lip-to-lid technique was a simple 1-stage method for reconstructing an upper eyelid of a cat following radical tumor resection that provided excellent functional and cosmetic results.

Concepts: Cancer, Surgery, Cat, Domestic shorthaired cat, Reconstruction era of the United States, Reconstruction, Excision, Neutering