Dissociated production of perforin, granzyme B, and IFN-gamma by HIV-specific CD8(+) cells in HIV infection

CD8(+) T cells play a crucial role in the control of viral infections such as HIV. The functional characterization of HIV-specific CD8(+) T cells has so far been largely restricted to studies of IFN-gamma. The TCR-triggered release of the effector molecules perforin (PFN) and granzyme B (GzB), however, is thought to be a central pathway for the destruction of virus-infected target cells by CD8(+) effector T cells. Here we would like to address two major findings. On the one hand we propose that ex vivo measurements of PFN and GzB secretion via ELISPOT may permit the distinction between in vivo resting versus activated CD8(+) memory T cells in healthy and HIV-infected individuals. Therefore, extending the present standard of IFN-gamma measurements to the analysis of PFN and GzB release in functional T cell assays will provide new insights into CD8(+) effector T cell functions. It should enable the evaluation of therapeutic vaccination efficacy by its ability to reactivate and convert IFN-gamma-positive, but GzB- and PFN-negative memory CD8(+) T cells into PFN/GzB-secreting effector cells. On the other hand, we report on a frequent ex vivo dissociation of the HIV peptide-induced secretion of PFN and GzB in chronic HIV infection underlining CD8(+) effector T cell diversity in this disease--an aspect that also has to be accounted for in immune monitoring approaches.     

1-Methylnicotinamide (MNA) prevents endothelial dysfunction in hypertriglyceridemic and diabetic rats

For many years, 1-methylnicotinamide (MNA), a primary metabolite of nicotinamide, has been considered inactive. Recently however, it has been discovered that MNA possesses anti-thrombotic and anti-inflammatory activity. In the present study we investigated whether chronic administration of MNAto hypertriglyceridemic or diabetic rats would reverse endothelial dysfunction characterized by the impairment of nitric oxide (NO)-dependent vasodilatation. Hypertriglyceridemia in rats was induced by fructose-rich (60%) diet, while diabetes was induced by streptozotocin injection (70 mg/kg). After eight weeks, in hypertriglyceridemic or diabetic rats treated or non-treated with MNA(100 mg/kg), we analyzed the magnitude of endothelium-dependent or endothelium-independent vasodilatation in aorta induced by acetylcholine or S-nitroso-N-acetyl-penicilamine (SNAP), respectively, as well as plasma concentration of: cholesterol, triglycerides, glucose, HbA(1c), fructosamine, peptide C, endogenous MNAand its metabolites (M2PY, M4PY). In diabetic rats plasma concentration of glucose, HbA(1c) and fructosamine was elevated (402.08 +/- 19.01 vs. 82.06 +/- 5.41 mg/dl, p < 0.001; 9.55 +/- 0.56 vs. 4.93 +/- 0.24%, p = 0.052 and 2.53 +/- 0.10 vs. 1.14 +/- 0.06 mmol DTF/mg protein, p < 0.001 in diabetic and control rats, respectively). In hypertriglyceridemic rats plasma concentration of triglycerides was elevated (4.25 +/- 0.27 vs. 1.55 +/- 0.12 mmol/l, p < 0.001 in hypertriglyceridemic and control rats, respectively). In both models the NO-dependent vasodilatation in aorta induced by acetylcholine was significantly impaired as compared to control rats, while the response to SNAP was largely preserved. In hypertriglyceridemic rats, 4 weeks of treatment with MNA(100 mg/kg, po) resulted in a three to six-fold increase in endogenous levels of MNA and its metabolites (M2PY and M4PY), the fall in triglycerides concentration in plasma (from 4.25 +/- 0.27 to 2.22 +/- 0.14 mmol/l, p < 0.001), and the preservation of the NO-dependent vasodilatation. In diabetic rats chronic treatment with MNAalso prevented the impairment of NO-dependent vasodilatation, while it displayed only a mild effect on hyperglycemia and did not lower triglycerides concentration. In summary, MNAtreatment decreased plasma triglycerides concentration in hypertriglyceridemic, but not in diabetic rats, while it prevented the development of endothelial dysfunction in aorta in both of these models. Accordingly, the ability of MNAto reverse endothelial dysfunction seems to be independent of its hypolipemic activity.     

Oxidative phenotype status in related subjects

Human population varies with regard to the rate of drug metabolism. Differences in pharmacological activity of a drug in patients who belong to the same population result from a different enzymatic activity and different genotypes of those subjects. The aim of the study was to assess the incidence of extensive (EM) and poor (PM) oxidative phenotypes in related persons and to establish whether any associations exist between an individual, genetically conditioned drug oxidation capacity and a family relationship. The study comprised 61 healthy subjects including 39 females and 22 males aged between 18 and 77 years (mean age 39.02 +/- 16.55 years). The persons belonged to 20 families and were first degree relatives. The oxidative phenotype status was established based on the metabolic ratio (MR); the amounts of urinary output of dextromethorphan and dextrorphan in the 10 h urine were determined using the HPLC method. Prevalence of poor metabolizers in the group of relatives reached 16.4%. The percentage of poor metabolizers was higher in the group of relatives than in the control group (9.6%), however, the difference was not statistically significant. Inheritance of the oxidative phenotype among relatives is mainly associated with mothers and their daughters.     

Synthesis and cytotoxicity testing of novel 2-(3-substituted-6-chloro-1,1-dioxo-1,4,2-benzodithiazin-7-yl)-3-phenyl-4(3H)-quinazolinones

A new series of thirteen 2-[3-(substituted amino)-6-chloro-1,1-dioxo-1,4,2-benzodithiazin-7-yl]-3-phenyl-4(3H)-quinazolinones 4-16 were prepared in order to evaluate their cytotoxic activity against 12 human cancer cell lines. The bioassay indicated that the quinazolinone derivatives 5, 8-12, 15, and 16 possess cancer-cell growth-inhibitory properties. Compounds 5 and 12 showed a high level of selectivity for certain cell lines. The most active compounds 9, 10, 15, and 16 showed moderate antiproliferative activity and were approximately 4-fold less potent than cisplatin.     

PAMAM G4 dendrimers lower high glucose but do not improve reduced survival in diabetic rats

For nearly a decade poly(amidoamine) (PAMAM) dendrimers G4 were claimed unnegligible cytotoxic agents. Here we monitored whether in vivo cytotoxic effect of PAMAM G4 (0.5 micromol kg(-1) day(-1)) may be compromised by its ameliorating effect on severe hyperglycaemia in chronic streptozotocin-diabetic Wistar rats. PAMAM G4 significantly reduced the 60-day overall survival in long-term experimental diabetes: treated animals were 6.7 times more likely to die than control animals (p<0.025). PAMAM G4 significantly reduced numerous biochemical parameters in blood, including glucose, glycated haemoglobin or protein oxidation, cholesterol and triglycerides, but apparently unchanged plasma insulin peptide C. Terminal blood glucose in PAMAM-treated animals was significantly higher in survivors, pointing to the possible preventive role of glycation in reducing of PAMAM G4 cytotoxicity. Our results provide the first in vivo evidence that PAMAM G4 is able to lower plasma glucose and suppress long-term markers of diabetic hyperglycaemia. Nevertheless, this beneficial influence cannot override PAMAM G4 cytotoxic effects in the increased mortality of streptozotocin-diabetic rats.     

Improving the provision of OTC medication information in community pharmacies in Poland

Background An informed or shared decision-making model is desirable to support the choice of over-the-counter (OTC) medications in pharmacies: it respects patient empowerment in self-medication. Such a model is achievable provided that pharmacists are a credible, competent information source open to patient needs. Objective To study the dependencies among selected factors that may influence the provision of OTC medication information. The study was conducted from the perspective of a community pharmacist. Method The study consisted of an auditorium survey with a self-administered questionnaire. We attempted to determine the relationships among three selected constructs: patient centredness (four items), competence (four items), and provision of OTC medication information (six items) as latent variables. We analysed hypothetical relationships among the observable variables and latent variables using structural equation modelling. Main outcome measure Selected factors that may influence the provision of OTC medication information. Results In all, 1496 pharmacists took part in the study. The model demonstrated adequate fit (χ² = 198.39, df = 64). The patient-centredness construct was demonstrated to have a strong direct positive impact on the provision of OTC medication information construct (β = 0.77, P < 0.05). Provision of OTC medication information was also shown to have a strong direct effect on the competence variable (β = 0.90, P < 0.05). Conclusion If a pharmacist is patient centred, there is a greater possibility that they will provide information about OTC medicines; that may influence the pharmacist’s feelings about their ability to cope with patient initiatives and enhance the pharmacist’s selfperceived competence.     

Medial malleolar osteotomy for the treatment of talar osteochondral lesions: anatomical and morbidity considerations

Purpose

Osteochondral lesions of the talus are often located posteromedially requiring open surgery to facilitate solid and complete osteochondral reconstruction. The aim of the study was to identify the optimal anatomical site for medial malleolar osteotomy based on the criteria of minimal cartilage damage (Study I) and to report on the morbidity in patients receiving osteotomy performed at the previously identified site (Study II).

Methods

For Study I, cartilage coverage of the tibiofibular ankle joint facet was measured in 40 cadaveric ankles (20 cadaver specimens). In Study II, we assessed clinical (VAS pain score, AOFAS score, range of motion) and radiological outcome measures (SPECT-CT) in 17 patients (mean age, 36.8 ± 10.8 years) undergoing medial malleolar osteotomy.

Results

The medial edge in the transition zone of the tibial plafond to the medial malleolus showed less than 75 % of cartilage coverage in 62.5 % of cadavers (Study I). Surgery resulted in lower pain levels (2.4 ± 2.6 compared with 6.3 ± 1.8 points; p < 0.001) and greater AOFAS scores (82.9 ± 14.1 compared with 43.5 ± 10.8 to points; p < 0.001) compared with baseline (Study II). No signs of intra-operative damage or mal- or non-union were found. Long-term morbidity was found in one patient. Implant removal was necessary in 12 of 17 patients (71 %).

Conclusion

Anatomically, there is an optimal location for the medial malleolar osteotomy at the medial ankle edge involving minimal cartilage damage. Clinical results using this location showed no short- or mid-term morbidity and little long-term morbidity. However, many patients required re-intervention for implant removal.

Level of evidence

IV.