Prognostic tools for hypertrophic scar formation based on fundamental differences in systemic immunity

Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP‐1, IL‐8, IL‐18 and IL‐23 levels have a strong correlation with HS (P < .010‐0.004; AUC = 0.790‐0.883). Notably, combinations of two or three cytokines (TNF‐a, MCP‐1 and IL‐23; AUC: 0.942, Nagelkerke R²: 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice.     

The effect of pressurized carbon dioxide as a temporary plasticizer and foaming agent on the hot stage extrusion process and extrudate properties of solid dispersions of itraconazole with PVP-VA 64.

The aim of the current research project was to explore the possibilities of combining pressurized carbon dioxide with hot stage extrusion during manufacturing of solid dispersions of itraconazole and polyvinylpyrrolidone-co-vinyl acetate 64 (PVP-VA 64) and to evaluate the ability of the pressurized gas to act as a temporary plasticizer as well as to produce a foamed extrudate. Pressurized carbon dioxide was injected into a Leistritz Micro 18 intermeshing co-rotating twin-screw melt extruder using an ISCO 260D syringe pump. The physicochemical characteristics of the extrudates with and without injection of carbon dioxide were evaluated with reference to the morphology of the solid dispersion and dissolution behaviour and particle properties. Carbon dioxide acted as plasticizer for itraconazole/PVP-VA 64, reducing the processing temperature during the hot stage extrusion process. Amorphous dispersions were obtained and the solid dispersion was not influenced by the carbon dioxide. Release of itraconazole from the solid dispersion could be controlled as a function of processing temperature and pressure. The macroscopic morphology changed to a foam-like structure due to expansion of the carbon dioxide at the extrusion die. This resulted in increased specific surface area, porosity, hygroscopicity and improved milling efficiency.     

Myocarditis and heart failure: need for better diagnostic, predictive, and therapeutic tools.

Viral infection of the heart is increasingly recognized as animportant cause of both acute and chronic heart failure. Enterovirusesand adenoviruses have been considered the most common pathogensof viral cardiomyopathy (CMP), but parvovirus B19 (PVB19) isincreasingly found in endomyocardial biopsies of patients withacute myocarditis or idiopathic dilated cardiomyopathy (ICM).^1,2In addition to direct cytopathic effects of these cardiotropicviruses, there is convincing evidence that autoimmune responsesinduced by viruses contribute to the heart disease in a significantsubset of patients with myocarditis.³ Caforio et al.⁴ present a prospective study in 174 consecutivepatients with myocarditis included between 1992 and 2005.     

Polarizing inclusions in some organs of children with congenital peroxisomal diseases (Zellweger's,Refsum's,chondrodysplasia punctata (rhizomelic form), X-linked adrenoleukodystrophy)

Summary Polarizing material has been reported in the liver of children with infantile Refsum's disease (IRD) and was absent in two patients with the cerebro-hepato-renal syndrome of Zellweger (CHRS). We examined in polarized light 15 liver biopsy and autopsy samples from six other patients with the cerebro-hepato-renal syndrome of Zellweger, two with the rhizomelic form of chondrodysplasia punctata (rCDP) and two with X-linked adrenoleukodystrophy (ALD), all conditions with deficient peroxisomes. Two types of birefringent inclusions were found in CHRS only: the first is transparent in bright field, the second appears as brown granules or rods, similar to lipofuscins. As in IRD large PAS-positive macrophage-like cells contain the transparent type. Electron microscopical investigation of these cells shows trilaminar structures within membrane-bound organelles. The two types were also seen in kidney and brown adipose tissue, the first type in pancreas, the second type in adrenal gland; no such was observed in myocardium or in thyroid gland (CHRS). No birefringent inclusions were present in rCDP and ALD. The nature of the inclusions is still unclear. An accumulation of the transparent polarizing material with increasing age of the patients is most likely.     

Annexin A5 and the failing heart; lost or found in translation?

Heart failure is the number one reason for hospital admissionin patients above 65 years of age. It is predicted that thenumber of heart failure patients will almost double in the next20 years. Ischaemic and hypertensive heart disease are the majorcauses of this disabling disease. Approximately 22% of womenand 46% of men who have had a myocardial infarction will developheart failure within 6 years.¹ Still, hypertension is a chiefcause of cardiac failure: diastolic dysfunction accounts for>50% of all heart failure patients.² In the world we livein, an increasing number of people become at risk of developinghypertension heart     

Disruption of the plasminogen gene in mice abolishes wound healing after myocardial infarction

The plasminogen system plays an important role in the proteolytic degradation of extracellular matrices during wound healing. In the present study we investigated the impact of the plasminogen system on cardiac wound healing and function after myocardial infarction. Myocardial infarction was induced in plasminogen-deficient mice (Plg-/-) and in wild-type controls (Plg+/+). Structural analysis 1, 2, and 5 weeks after infarction revealed that infarct healing was virtually abolished in Plg-/- mice, indicating that the plasminogen system is required for the repair process of the heart after infarction. In the absence of plasminogen, inflammatory cells did not migrate into the infarcted myocardium. Necrotic cardiomyocytes were not removed and the formation of granulation tissue and fibrous tissue did not occur. In these non-healing infarcted hearts, LV dilatation was not altered. In addition, gelatinolytic activity of MMP-2 and MMP-9 was depressed in the Plg-/- infarcted hearts, suggesting that the plasmin effect on infarct healing may be mediated by MMPs. Surprisingly, cardiac function was only attenuated to a rather small extent in the Plg-/- infarcted mice when compared to the wild-types. This study provides direct prove that plasmin-mediated proteolysis plays a central role in cardiac wound healing after myocardial infarction in mice.     

Rapid detection of Candida albicans in clinical blood samples by using a TaqMan-based PCR assay

We describe a rapid and reproducible PCR assay for quantitation of the Candida albicans ribosomal DNA (rDNA) in clinical blood samples based on the TaqMan principle (Applied Biosystems), in which a signal is generated by cleavage of a template-specific probe during amplification. We used two fluorogenic probes based on universal, fungus-specific primers, one for the detection of C. albicans species DNA and one for the detection of all Candida genus DNA. C. albicans blastoconidia mixed with whole blood in a titration experiment yielded a linear PCR signal over a range of 3 orders of magnitude. The TaqMan-based PCR assay for C. albicans exhibited a low limit of detection (5 CFU/ml of blood) and an excellent reproducibility (96 to 99%). While the C. albicans species-specific probe had 100% specificity for C. albicans, all Candida genus-specific probes cross-reacted with other organisms likely to coinfect patients with C. albicans infections. On the basis of these data, we determined the C. albicans loads with a species-specific probe from 122 blood samples from 61 hematology or oncology patients with clinically proven or suspected systemic Candida infections. Eleven positive samples exhibited a wide range of C. albicans loads, extending from 5 to 100,475 CFU/ml of blood. The sensitivity and specificity of the present assay were 100 and 97%, respectively, compared with the results of blood culture. These data indicate that the TaqMan-based PCR assay for quantitation of C. albicans with a species-specific probe provides an attractive alternative for the identification and quantitation of C. albicans rDNA in pure cultures and blood samples.     

Variable selection under multiple imputation using the bootstrap in a prognostic study

Background  

Missing data is a challenging problem in many prognostic studies. Multiple imputation (MI) accounts for imputation uncertainty that allows for adequate statistical testing. We developed and tested a methodology combining MI with bootstrapping techniques for studying prognostic variable selection.     

Stability of benefits of mime therapy in sequelae of facial nerve paresis during a 1-year period.

OBJECTIVE: To assess the stability of benefits of mime therapy, a modality of physiotherapy for patients with facial nerve paresis, during a period of 1 year. STUDY DESIGN: A prospective follow-up build on a randomized clinical trial in which a treatment group is compared with a control group. SETTING: Physiotherapy outpatient department. PATIENTS: Forty-eight patients with a history of a facial nerve paresis of 9 months or more. INTERVENTION: Mime therapy. METHOD: Sequelae of facial nerve paresis were measured using the same measurement instruments as in the randomized clinical trial--the Sunnybrook and the House-Brackmann (HB) Facial Grading Systems, the lip length and pout indices, a stiffness scale, and the Facial Disability Index. Stability of outcome level and of interpatient differences is analyzed. RESULTS: Of the 46 patients who completed the follow-ups, repeated-measures analyses of covariance revealed no significant differences in the average scores nor significant trends of the posttherapy measurements, except for the pout index and the Facial Disability Index-social. For six sequelae (except HB), 95% of patient-sequel combinations showed immediate improvement after mime therapy, for HB grades this was 74%. Where sequelae improved, the posttherapy individual courses (T2-T3-T4) showed, also for HB, in majority absence of deterioration; benefits obtained were stable. CONCLUSION: Mime therapy is effective in patients with facial nerve paresis and benefits are stable 1 year after therapy.