Resistance to activated protein C in a patient with multiple myocardial infarctions and stroke--a case report

A case of a 49-year-old female with a history of two myocardial infarctions (MI) and ischaemic stroke is presented. The patient was admitted to the hospital due to a third acute MI. Laboratory investigations revealed resistance to activated protein C due to factor V Leiden mutation. Diagnosis and treatment of patients with this condition are discussed.     

Are triglyceride-rich lipoproteins associated with aortic valve sclerosis? A preliminary report

Background: Evidence linking cardiovascular risk factors to aortic valve sclerosis (AVS) has led to the assumption that the latter is an atherosclerosis-like process. However, triglyceride (TG)-rich lipoproteins, an important risk factor for atherosclerosis, have been rarely investigated in connection with AVS. Methods: A cross-sectional study of 246 healthy individuals (mean age 59±6 years, 77% men) was conducted. Subjects underwent an echocardiographic assessment and extensive blood lipid measurements, including evaluation of TG-related indices, such as serum apolipoprotein (apo) C_II and C_III levels, apo C_III levels in VLDL+LDL particles, and apo C_III ratio (C_III level in HDL/C_III level in VLDL+LDL). Results: Twenty-three patients (9.3%) were diagnosed as having AVS. On average, these patients were 5 years older and had higher levels of serum cholesterol, LDL-C and LP(a), compared with non-AVS subjects. In addition, the AVS patients exhibited higher concentrations of serum apo C_II, serum apo C_III and apo C_III in VLDL+LDL, and a lower apo C_III ratio. Adjusting for age and gender, a 1 S.D. increment in apo C_III in VLDL+LDL was associated with odds ratio (OR) of 1.76 (95% CI: 1.17–2.65) for AVS. Further adjustment for atherosclerotic risk factors did not alter the association appreciably (OR=1.65, 95% CI: 1.06–2.58). Conclusion: TG-rich lipoproteins may be involved in the early development of AVS. Confirmation in prospective studies is required.     

Gentamicin affects melanogenesis in normal human melanocytes

Background: Aminoglycoside antibiotics, including gentamicin, despite their ability to induce adverse effects on pigmented tissues, remain valuable and sometimes indispensable for the treatment of various infections. It is known that gentamicin binds to melanin biopolymers, but the relation between this drug affinity to melanin and its toxicity is not well documented. The aim of this work was to examine the impact of gentamicin on viability and melanogenesis in HEMa-LP (light pigmented) and HEMn-DP (dark pigmented) normal human melanocytes.

Methodology/principal findings: The effect of gentamicin on cell viability was determined by 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST-1) assay; melanin content and tyrosinase activity were measured spectrophotometrically. It has been demonstrated that gentamicin induces concentration-dependent loss in melanocytes viability. The application of antibiotic in concentration of 10?mM causes higher reduction in viability of the light pigmented melanocytes (by about 74%) when compared with the dark pigmented ones (by about 62%). The value of the concentration of a drug that produces loss in cell viability by 50% (EC₅₀) for both cell lines was found to be ～7.5?mM. It has been shown that gentamicin causes inhibition of tyrosinase activity and reduces melanin content in light pigmented melanocytes significantly more than in the dark pigmented cells.

Conclusion/significance: We have found that gentamicin modulates melanization process in melanocytes in vitro, what may explain the potential role of melanin biopolymer in the mechanisms of undesirable toxic effects of this drug in vivo, as a result of its accumulation in pigmented tissues. We have also stated that the melanogenesis process in light pigmented melanocytes is more sensitive to the inhibitory effect of gentamicin than in the dark pigmented cells.     

Model-Based Determination of Effective Blood Concentrations of Cyclosporine for Neutrophil Response in the Treatment of Severe Aplastic Anemia in Children

Optimal immunosuppressive therapy in acquired severe aplastic anemia (SAA) remains to be refined, especially cyclosporine (CsA) use. Current recommendations state that CsA trough blood concentrations (TBC) should be maintained between 200 and 400 ng/mL despite the lack of supporting data. This study aimed at quantifying relationships between CsA exposure and neutrophil response and determining an effective range for CsA TBC. Twenty-three SAA patients treated with CsA were retrospectively analyzed. Nonlinear mixed effect modeling approaches were used to develop a pharmacokinetic-pharmacodynamic model. The pharmacokinetic model described the relationships between CsA doses and TBC. The pharmacodynamic model allowed to estimate boundaries for optimal CsA effects, neutrophils being used as biomarker of response. A time-to-event model linked effective concentration to time-to-therapeutic success. CsA TBC were adequately described by a two-compartment model with first-order absorption, a lag time, and a linear elimination. The efficient range of CsA TBC was estimated between 87 and 120 ng/mL. Model-based simulations and external validation in three additional patients confirmed these results. This original modeling approach was successful in describing the relationship between CsA TBC and neutrophil response in SAA patients. Although further evaluation of the model is necessary, this work suggests that an optimal CsA TBC target of 100 ng/mL would be associated with a better neutrophil response in children with SAA.KEY WORDS: aplastic anemia, cyclosporine, modeling, pharmacokinetics, regulatory T lymphocytes     

Toxocara canis infection: Unusual trigger of systemic lupus erythematosus

Infection by Toxocara canis can cause systemic vasculitis. We report here a unique case of systemic lupus erythematosus (SLE) triggered by T. canis infection. An 8‐year‐old girl was treated with albendazole therapy for common toxocariasis, but she developed two weeks later, asthenia, fever, infiltrated maculopapular eruption of the face, peripheral vascular disease with necrosis of the fingers and inflammatory anemia with proteinuria. Anti‐nuclear, anti‐DNA and anti‐Sm antibodies positivity, together with minimal change nephritis with mesangial exclusive IgM deposit on renal biopsy and clinical relapse after initially successful steroid therapy, led to the diagnosis of SLE. T. canis infection can trigger systemic lupus but must also be ruled out of the differential diagnosis given its association with autoimmunity.     

Nanocomposite Foams of Polypropylene and Carbon Nanotubes: Preparation,Characterization, and Evaluation of their Performance as EMI Absorbers

Highly expanded nanocomposite foams of polypropylene and carbon nanotubes (PP/CNT) are formed using supercritical carbon dioxide (scCO₂) technology. The foaming parameters (temperature, pressure) are investigated to establish their influence on the morphology of the resulting foams and their impact on the electrical conductivity. As promising electromagnetic‐interference (EMI) absorbers, the EMI shielding performance of the foams is determined, and a preliminary relationship is established between foam morphology and the EMI shielding performance. The best candidates are highly expanded foams with a volume expansion of >25, containing 0.1 vol% CNTs; they are able to absorb more than 90% of the incident radiation between 25 and 40 GHz.

     

SMAD2 Mutations Are Associated with Arterial Aneurysms and Dissections

We report three families with arterial aneurysms and dissections in which variants predicted to be pathogenic were identified in SMAD2. Moreover, one variant occurred de novo in a proband with unaffected parents. SMAD2 is a strong candidate gene for arterial aneurysms and dissections given its role in the TGF‐β signaling pathway. Furthermore, although SMAD2 and SMAD3 probably have functionally distinct roles in cell signaling, they are structurally very similar. Our findings indicate that SMAD2 mutations are associated with arterial aneurysms and dissections and are in accordance with the observation that patients with pathogenic variants in genes encoding proteins involved in the TGF‐β signaling pathway exhibit arterial aneurysms and dissections as key features     

Infection-related ventilator-associated complications in ICU patients colonised with extended-spectrum β-lactamase-producing Enterobacteriaceae

Purpose

To investigate the clinical significance of infection-related ventilator-associated complications (IVAC) and their impact on carbapenem consumption in mechanically ventilated (MV) patients colonised with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBLE).

Methods

Inception cohort study from the French prospective multicenter OUTCOMEREA database (17 ICUs, 1997–2015) including all ESBLE carriers (systematic rectal swabbing at admission then weekly and/or urinary or superficial surgical site colonisation) with MV duration?>?48 h and?≥?1 episode of IVAC after carriage documentation. All ICU-acquired infections were microbiologically documented.

Results

The 318 enrolled ESBLE carriers (median age 68 years; males 67%; medical admission 68%; imported carriage 53%) experienced a total of 576 IVAC comprising 361 episodes (63%) without documented infection, 124 (21%) related to infections other than ventilator-associated pneumonia (VAP), 73 (13%) related to non-ESBLE VAP and 18 (3%) related to ESBLE VAP. Overall, ESBLE infections accounted for only 43 episodes (7%). Carbapenem exposure within the preceding 3 days was the sole independent predictor of ESBLE infection as the causative event of IVAC, with a protective effect (adjusted odds ratio 0.2, 95% confidence interval 0.05–0.6; P?<?0.01). Carbapenems were initiated in 9% of IVAC without infection, 15% of IVAC related to non-VAP infections, 42% of IVAC related to non-ESBLE VAP, and 56% of IVAC related to ESBLE VAP (ESBLE VAP versus non-ESBLE VAP: P?=?0.43).

Conclusions

IVAC in ESBLE carriers mostly reflect noninfectious events but act as a strong driver of empirical carbapenem consumption. ESBLE infections are scarce yet hard to predict, strengthening the need for novel diagnostic approaches and carbapenem-sparing alternatives.

     

Milk Consumption and Mortality from All Causes,Cardiovascular Disease,and Cancer: A Systematic Review and Meta-Analysis

Results from epidemiological studies of milk consumption and mortality are inconsistent. We conducted a systematic review and meta-analysis of prospective studies assessing the association of non-fermented and fermented milk consumption with mortality from all causes, cardiovascular disease, and cancer. PubMed was searched until August 2015. A two-stage, random-effects, dose-response meta-analysis was used to combine study-specific results. Heterogeneity among studies was assessed with the I² statistic. During follow-up periods ranging from 4.1 to 25 years, 70,743 deaths occurred among 367,505 participants. The range of non-fermented and fermented milk consumption and the shape of the associations between milk consumption and mortality differed considerably between studies. There was substantial heterogeneity among studies of non-fermented milk consumption in relation to mortality from all causes (12 studies; I² = 94%), cardiovascular disease (five studies; I² = 93%), and cancer (four studies; I² = 75%) as well as among studies of fermented milk consumption and all-cause mortality (seven studies; I² = 88%). Thus, estimating pooled hazard ratios was not appropriate. Heterogeneity among studies was observed in most subgroups defined by sex, country, and study quality. In conclusion, we observed no consistent association between milk consumption and all-cause or cause-specific mortality.