para-Nitroblebbistatin, the non-cytotoxic and photostable myosin II inhibitor

Blebbistatin, the best characterized myosin II-inhibitor, is commonly used to study the biological roles of various myosin II isoforms. Despite its popularity, the use of blebbistatin is greatly hindered by its blue-light sensitivity, resulting in phototoxicity and photoconversion of the molecule. Additionally, blebbistatin has serious cytotoxic side effects even in the absence of irradiation, which may easily lead to the misinterpretation of experimental results since the cytotoxicity-derived phenotype could be attributed to the inhibition of the myosin II function. Here we report the synthesis as well as the in vitro and in vivo characterization of a photostable, C15 nitro derivative of blebbistatin with unaffected myosin II inhibitory properties. Importantly, para-nitroblebbistatin is neither phototoxic nor cytotoxic, as shown by cellular and animal tests; therefore it can serve as an unrestricted and complete replacement of blebbistatin both in vitro and in vivo.

Coherent phonon dynamics in micro- and nanocrystalline diamond

We report on the time-resolved coherent anti-Stokes Raman spectroscopy of phonon dephasing in micro- and nanocrystalline diamond films. The dephasing times T(2) were found to be dependent on the morphology of diamond films (average size of crystals and content of nondiamond carbon phase) and changed from 0.7 to 1.72 ps. The dephasing times were found to be temperature independent in the range 10-295 K. In addition to diamond Raman active phonon mode at 1332 cm(-1), we investigated also the dynamics of a broad Raman peak at 1530 cm(-1) which is present in samples with higher content of nondiamond sp(2) hybridized carbon phase. This peak was found to be homogenously broadened with very fast dephasing (T(2)~50 fs).

Autophagy is required for zebrafish caudal fin regeneration

Regeneration is the ability of multicellular organisms to replace damaged tissues and regrow lost body parts. This process relies on cell fate transformation that involves changes in gene expression as well as in the composition of the cytoplasmic compartment, and exhibits a characteristic age-related decline. Here, we present evidence that genetic and pharmacological inhibition of autophagy - a lysosome-mediated self-degradation process of eukaryotic cells, which has been implicated in extensive cellular remodelling and aging - impairs the regeneration of amputated caudal fins in the zebrafish (Danio rerio). Thus, autophagy is required for injury-induced tissue renewal. We further show that upregulation of autophagy in the regeneration zone occurs downstream of mitogen-activated protein kinase/extracellular signal-regulated kinase signalling to protect cells from undergoing apoptosis and enable cytosolic restructuring underlying terminal cell fate determination. This novel cellular function of the autophagic process in regeneration implies that the role of cellular self-digestion in differentiation and tissue patterning is more fundamental than previously thought.

Both autologous bone marrow mononuclear cell and peripheral blood progenitor cell therapies similarly improve ischaemia in patients with diabetic foot in comparison with control treatment

BACKGROUND

The aim of our study was to compare the effect of bone marrow mononuclear cell and peripheral blood progenitor cell therapies in patients with diabetic foot disease and critical limb ischaemia unresponsive to revascularization with conservative therapy.

METHODS

Twenty-eight patients with diabetic foot disease (17 treated by bone marrow cells and 11 by peripheral blood cell) were included into an active group and 22 patients into a control group without cell treatment. Transcutaneous oxygen pressure and rate of major amputation, as the main outcome measures, were compared between bone marrow cells, peripheral blood cell and control groups over 6 months; both cell therapy methods were also compared by the characteristics of cell suspensions. Possible adverse events were evaluated by changes of serum levels of angiogenic cytokines and retinal fundoscopic examination.

RESULTS

The transcutaneous oxygen pressure increased significantly (p < 0.05) compared with baseline in both active groups after 6 months, with no significant differences between bone marrow cells and peripheral blood cell groups; however, no change of transcutaneous oxygen pressure in the control group was observed. The rate of major amputation by 6 months was significantly lower in the active cell therapy group compared with that in the control group (11.1% vs. 50%, p = 0.0032), with no difference between bone marrow cells and peripheral blood cell. A number of injected CD34+ cells and serum levels of angiogenic cytokines after treatment did not significantly differ between bone marrow cells and peripheral blood cell.

CONCLUSIONS

Our study showed a superior benefit of bone marrow cells and peripheral blood cell treatments of critical limb ischaemia in patients with diabetic foot disease when compared with conservative therapy. There was no difference between both cell therapy groups, and no patient demonstrated signs of systemic vasculogenesis.

Complex regulation of autophagy in cancer - integrated approaches to discover the networks that hold a double-edged sword

Autophagy, a highly regulated self-degradation process of eukaryotic cells, is a context-dependent tumor-suppressing mechanism that can also promote tumor cell survival upon stress and treatment resistance. Because of this ambiguity, autophagy is considered as a double-edged sword in oncology, making anti-cancer therapeutic approaches highly challenging. In this review, we present how systems-level knowledge on autophagy regulation can help to develop new strategies and efficiently select novel anti-cancer drug targets. We focus on the protein interactors and transcriptional/post-transcriptional regulators of autophagy as the protein and regulatory networks significantly influence the activity of core autophagy proteins during tumor progression. We list several network resources to identify interactors and regulators of autophagy proteins. As in silico analysis of such networks often necessitates experimental validation, we briefly summarize tractable model organisms to examine the role of autophagy in cancer. We also discuss fluorescence techniques for high-throughput monitoring of autophagy in humans. Finally, the challenges of pharmacological modulation of autophagy are reviewed. We suggest network-based concepts to overcome these difficulties. We point out that a context-dependent modulation of autophagy would be favored in anti-cancer therapy, where autophagy is stimulated in normal cells, while inhibited only in stressed cancer cells. To achieve this goal, we introduce the concept of regulo-network drugs targeting specific transcription factors or miRNA families identified with network analysis. The effect of regulo-network drugs propagates indirectly through transcriptional or post-transcriptional regulation of autophagy proteins, and, as a multi-directional intervention tool, they can both activate and inhibit specific proteins in the same time. The future identification and validation of such regulo-network drug targets may serve as novel intervention points, where autophagy can be effectively modulated in cancer therapy.

Schizophrenia patients with and without post-traumatic stress disorder (PTSD) have different mood symptom levels but same cognitive functioning

OBJECTIVE

To investigate differences in cognitive function and level of psychopathology in patients with schizophrenia (SZ) with or without psychological traumatization/post-traumatic stress disorder (PTSD). We hypothesized that traumatized patients with or without PTSD would have more severe cognitive impairments because of the neuropathological changes associated with PTSD, and more severe psychopathology compared with non-traumatized SZ patients.

METHOD

Seventy-five SZ patients with traumatization and 217 SZ patients without traumatization were evaluated regarding the symptoms and cognitive functioning, using standard symptom scales (PANSS; CDSS) and a neuropsychological test battery (IQ, verbal memory, attention, working memory, psychomotor speed, and executive functioning).

RESULTS

No significant differences were observed between the groups in cognitive test performance. The patients in the traumatized group with PTSD showed significantly more current depression than the non-traumatized group (P = 0.012).

CONCLUSION

The findings did not support the hypothesis that the presence of comorbid PTSD/traumatization in SZ is associated with increased cognitive impairment. The increase in current depression in SZ with comorbid traumatization suggests that more severe psychopathology is associated with traumatization.

Randomised clinical trial: a 1-week, double-blind, placebo-controlled study of pancreatin 25 000 Ph. Eur. minimicrospheres (Creon 25000 MMS) for pancreatic exocrine insufficiency after pancreatic surgery, with a 1-year open-label extension

BACKGROUND

Pancreatic exocrine insufficiency (PEI) often occurs following pancreatic surgery.

AIM

To demonstrate the superior efficacy of pancreatin 25 000 minimicrospheres (Creon 25000 MMS; 9-15 capsules/day) over placebo in treating PEI after pancreatic resection.

METHODS

A 1-week, double-blind, randomised, placebo-controlled, parallel-group, multicentre study with a 1-year, open-label extension (OLE). Subjects ≥18 years old with PEI after pancreatic resection, defined as baseline coefficient of fat absorption (CFA) <80%, were randomised to oral pancreatin or placebo (9-15 capsules/day: 3 with main meals, 2 with snacks). In the OLE, all subjects received pancreatin. The primary efficacy measure was least squares mean CFA change from baseline to end of double-blind treatment (ancova).

RESULTS

All 58 subjects randomised (32 pancreatin, 26 placebo) completed double-blind treatment and entered the OLE; 51 completed the OLE. The least squares mean CFA change in the double-blind phase was significantly greater with pancreatin vs. placebo: 21.4% (95% CI: 13.7, 29.2) vs. -4.2% (-12.8, 4.5); difference 25.6% (13.9, 37.3), P < 0.001. The mean ± s.d. CFA increased from 53.6 ± 20.6% at baseline to 78.4 ± 20.7% at OLE end (P < 0.001). Treatment-emergent adverse events occurred in 37.5% subjects on pancreatin and 26.9% on placebo during double-blind treatment, with flatulence being the most common (pancreatin 12.5%, placebo 7.7%). Only two subjects discontinued due to treatment-emergent adverse events, both during the OLE.

CONCLUSIONS

This study demonstrates superior efficacy of pancreatin 25 000 over placebo in patients with PEI after pancreatic surgery, measured by change in CFA. Pancreatin was generally well tolerated at the high dose administered (EudraCT registration number: 2005-004854-29).

Significance of mycophenolate monitoring in liver transplant recipients: toward the cut-off level

Mycophenolate mofetil blocks the "de novo" -purine synthesis to reduce the incidence and severity of acute rejection episodes. There has been an increased interest in utility of monitoring mycophenolic acid (MPA) levels, however currently the MPA monitoring is not part of the protocol following liver transplantation. We assessed whether trough MPA monitoring could be advisable in liver transplant patients or not. For this reason MPA levels of 56 liver transplants were measured on 3, 5, 10, 14, 21, 30, 60, and 180 posttransplant days. The optimal cut-off of MPA level (≥1.73 mg/L) for all (56) and ≥1.34 mg/L for ciclosporin-treated- and ≥1.98 mg/L for the tacrolimus-treated transplants were calculated by statistical analysis to reduce the incidence of acute rejection. MPA concentrations of 3 days period before the day of clinical diagnosis acute rejection were well below the cut-off value. Only 3 (16%) out 19 patients with acute rejection had higher MPA levels than the cut-off value on the day of diagnosis of acute rejection. In conclusion, our data suggests that MPA predose level monitoring, especially in the early "filling phase" after transplantation, is applicable in liver allograft recipients given adjunctive MMF, protecting them from the ineffective immunosuppression.

Role of Aspergilli and Penicillia in mycotoxin contamination of maize in Hungary

Aspergillus and Penicillium species and their mycotoxins, including aflatoxins, ochratoxins, fumonisins and patulin, are frequently encountered on cereal products. The occurrence of these species and their mycotoxins on maize was investigated in Hungary after harvest in two consecutive years. Surface-sterilized cereal seeds were placed on selective media, and the isolated fungal strains were identified using morphological methods. In 2010 and 2011, 81.94% and 14.33%, respectively, of the samples were found to be contaminated with potentially toxigenic isolates. The species identification of selected isolates was carried out using sequence-based methods. Several Aspergillus flavus isolates were identified, which are potential aflatoxin producers. Other mycotoxinproducing species were also isolated, including black Aspergilli, which potentially produce ochratoxins and fumonisins, and A. clavatus, which produces patulin. In 2010 a large number of Penicillium species occurred in the samples, producing a wide range of mycotoxins. The mycotoxin content of the samples was analysed using the ELISA and HPLC techniques. Aflatoxins were not detected in any of the samples, while ochratoxins and fumonisins were successfully identified in some of the maize seeds.

Tacrolimus inhibits intimal hyperplasia in arterialised veins in rats

OBJECTVES

We investigated whether tacrolimus (FK506) can inhibit neointimal formation in arterialised vein grafts in rats.

METHODS

Lewis iliolumbar veins were implanted into the abdominal aorta of isogeneic rats. Animals in the treatment groups had daily intramuscular injections of tacrolimus at 0.2 mg/kg (group B) and 0.1 mg/kg (Group C), respectively. The control group A had no treatment. Light microscope evaluations of arterialised vein grafts were performed 30 days after operation. We determined the presence of endothelial cells, the thickness of intima and media, and the degree of infiltration by MHC class II positive, CD4 positive, and CD8 positive cells into the adventitia.

RESULTS

The intimal thickness in group B (5.0±1.0 µm) was statistically lower (P < 0.05) when compared to group C (7.0±3.0 µm). The intimal thickness in untreated group A (12.7±7.0 µm) was statistically higher (P < 0.01) when compared to both treated groups B and C, respectively. The medial thickness and degree of adventitial infiltration by MHC class II positive, CD8 positive, and CD4 positive cells did not differ between groups.

CONCLUSION

Treatment with tacrolimus (FK506) showed a dose dependant inhibition of neointimal hyperplasia in arterialised vein grafts in rats (Tab. 1, Fig. 3, Ref. 22).

Semantics boosts syntax in artificial grammar learning tasks with recursion

Center-embedded recursion (CER) in natural language is exemplified by sentences such as "The malt that the rat ate lay in the house." Parsing center-embedded structures is in the focus of attention because this could be one of the cognitive capacities that make humans distinct from all other animals. The ability to parse CER is usually tested by means of artificial grammar learning (AGL) tasks, during which participants have to infer the rule from a set of artificial sentences. One of the surprising results of previous AGL experiments is that learning CER is not as easy as had been thought. We hypothesized that because artificial sentences lack semantic content, semantics could help humans learn the syntax of center-embedded sentences. To test this, we composed sentences from 4 vocabularies of different degrees of semantic content due to 3 factors (familiarity, meaning of words, and semantic relationship between words). According to our results, these factors have no effect one by one but they make learning significantly faster when combined. This leads to the assumption that there were different mechanisms at work when CER was parsed in natural and in artificial languages. This finding questions the suitability of AGL tasks with artificial vocabularies for studying the learning and processing of linguistic CER.

Lymphedema treatment decreases pain intensity in lipedema

Lipedema is a disproportional obesity featuring light pressure-induced or spontaneous pain. On the basis of our clinical observations, lymphedema therapy, as practiced in our clinic, reduces the perception of pain beyond leg volume reduction. We therefore aimed to measure pain intensity prior and subsequent to treatment. 38 women with lipedema were enrolled in the study with 19 patients undergoing treatment and 19 serving as the control group using exclusively moisturizers. Treatment consisted of once daily manual lymph drainage (MLD), intermittent pneumatic compression (IPC), and multilayered short-stretch bandaging performed throughout a 5-day-course. Pain was evaluated with a 10-item questionnaire, a pain rating scale (PRS), and the Wong-Baker Faces scale. Treatment resulted in a significant reduction of pain with a decrease in mean scores of all three measures. In the control group, only PRS showed significant decrease. Our study results indicate that this treatment regimen not only reduces leg volume and capillary fragility, but also improves pain intensity in patients with lipedema.

Cytomegalovirus seroprevalence among solid organ donors in Hungary: correlations with age, gender, and blood group

BACKGROUND

Cytomegalovirus (CMV) is endemic throughout the world, affecting most of the population, but the seroprevalence of CMV is known to vary among countries. CMV causes a mild infection in persons with intact immunity; however, CMV infection in organ transplantation is associated with significant morbidity and mortality. The present retrospective study was designed to evaluate the age-, gender-, and blood group-adjusted CMV seroprevalence among solid organ donors, representing fairly the overall Hungarian population (according to Hungarian Central Statistic Institute). This information is important for calculating risk-factors for CMV-seronegative recipients. No nationwide estimates of CMV seroprevalence in Hungary (as a representative of Eastern Middle Europe) have been published yet.

METHODS

We investigated 2070 organ donors for CMV seroprevalence by measuring the CMV-specific immunoglobulin G. The donors were divided into 3 age groups (2-20, 21-50, and 51-70 years old). A study was also conducted on a fourth group consisting of 200 residents from an old age home. CMV seroprevalence differences were searched according to age-, gender- and blood-group distribution.

RESULTS

The CMV seroprevalence of organ donors is 85% and of all investigated persons is 86%. The age-specific prevalence increases, starting from 72% in the first group to 99% in the fourth group. Seroprevalence of females was found to be significantly higher than of males (P=.0001).

CONCLUSION

We have shown that the overall CMV seroprevalence in the Hungarian population is moderately high at 86%. The opportunity for CMV-seronegative recipients to get a graft from a seronegative donor is statistically only 2%. The seroprevalence of the youngest age group is 72% and so it can be concluded that the Hungarian population acquires the infection mainly in childhood or in the early adulthood. Female gender is a risk factor for CMV infection. This fact must be taken into consideration during the planning of patients' follow-up, prophylaxis, and therapy.

Correct anteroposterior patterning of the zebrafish neurectoderm in the absence of the early dorsal organizer

Background

The embryonic organizer (i.e., Spemann organizer) has a pivotal role in the establishment of the dorsoventral (DV) axis through the coordination of BMP signaling. However, as impaired organizer function also results in anterior and posterior truncations, it is of interest to determine if proper anteroposterior (AP) pattern can be obtained even in the absence of early organizer signaling.

Results

Using the ventralized, maternal effect ichabod (ich) mutant, and by inhibiting BMP signaling in ich embryos, we provide conclusive evidence that AP patterning is independent of the organizer in zebrafish, and is governed by TGFβ, FGF, and Wnt signals emanating from the germ-ring. The expression patterns of neurectodermal markers in embryos with impaired BMP signaling show that the directionality of such signals is oriented along the animal-vegetal axis, which is essentially concordant with the AP axis. In addition, we find that in embryos inhibited in both Wnt and BMP signaling, the AP pattern of such markers is unchanged from that of the normal untreated embryo. These embryos develop radially organized trunk and head tissues, with an outer neurectodermal layer containing diffusely positioned neuronal precursors. Such organization is reflective of the presumed eumetazoan ancestor and might provide clues for the evolution of centralization in the nervous system.

Conclusions

Using a zebrafish mutant deficient in the induction of the embryonic organizer, we demonstrate that the AP patterning of the neuroectoderm during gastrulation is independent of DV patterning. Our results provide further support for Nieuwkoop's "two step model" of embryonic induction. We also show that the zebrafish embryo can form a radial diffuse neural sheath in the absence of both BMP signaling and the early organizer.

[Treatment of critical limb ischemia and diabetic foot disease by the use of autologous stem cells]

AIM

The aim of our study was to assess safety and effectiveness of therapy of critical limb ischaemia by autologous stem cells and evaluation of potential adverse events.

METHODS

Fourteen patients were included into the study (11 men, 3 women, mean age 61.9 +/- 9.6 years, mean diabetes duration 23.5 +/- 11.1 years, mean glycated hemoglobin 6 +/- 1%). Eight patients were treated by bone marrow stromal cells, 6 patients by peripheral blood progenitor cells after stimulation by filgrastim. The suspension of stem cells was then applied into the muscles of ischemic limbs. We evaluated transcutaneous oxygen tension (TcPO2), subjective pain sensation assessed by Visual Analog Scale (VAS) and wound healing.

RESULTS

TcPO2 significantly increased in all patients from 10 +/- 8.7 mm Hg before the treatment to 39.4 +/- 9.5 mm Hg after 6 months (p = 0.0005) after stem cell therapy. We also observed significant area defect reduction and pain decrease during the follow-up period. Median of area defect was reduced from 4.3 (0.7 - 31.7) before the treatment to 0.06 (0 - 0.5) cm2 after 6 months from the treatment (p = 0.0078). Decrease in rest pain was observed in all patients, mean VAS decreased from 5.3 +/- 1.8 to 1.1 +/- 1.3 after 6 months (p = 0.002).

CONCLUSION

Our study suggests that stem cell therapy of diabetic foot disease is an effective therapeutic option with no adverse events for patients with severe peripheral arterial disease. This treatment leads to increase of transcutaneous oxygen tension, improves wound healing and decreases the rest pain.

Smoking following renal transplantation in Hungary and its possible deleterious effect on renal graft function

Smoking is a known risk factor for kidney damage and also influences graft function following renal transplantation. Because smoking habits following kidney transplantation are not systematically evaluated, we analyzed them in a single center in Hungary. The survey was conducted among 402 randomly selected kidney graft recipients. We assessed smoking-related questions as well as clinical kidney disease and transplantation data. Posttransplantation renal function was analyzed based on serum creatinine values at 1 month and at 3 years after transplantation. In our study 25% (n = 102) of patients continued to smoke after transplantation. Smokers who received grafts displayed a significantly younger age compared with nonsmokers (40.1 +/- 13.4 vs 47.1 +/- 12.7 years; P < .001) independent of underlying kidney disease. Posttransplantation kidney function in smokers did not differ at 1 month after engraftment, but was significantly impaired at 3 years as assessed based on serum creatinine levels: 138.9 +/- 42.4 versus 128.4 +/- 48.5 micromol/L (P < .05). Decrease of renal function correlated with smoking intensity defined in pack-years (r(2) = 0.102; P < .05). Smoking is common following kidney transplantation in Hungary and might represent a risk factor for kidney damage following renal transplantation. Therefore, effective tobacco-dependence treatment is necessary in this patient population.

Postconditioning attenuates remote organ injury after lower limb arterial occlusion

Introduction

External aortic compression due to acute gastric dilation is a rare etiology of the lower limb ischemia. This phenomenon leads the author to design experimental study for reperfusion syndrome. The lower limb ischemia-reperfusion (IR) injury consists of local and systemic components called the reperfusion syndrome. It can progrediate into a multi-organ failure which defines postoperative survival. A postconditioning is a surgical technique, which has a potential to reduce IR injury, therefore to prohibit the development of reperfusion syndrome.

Aim

XXXto examine on an experimental model, whether postonditioning is a practicable technique in infarenal aortic surgeries.

Materials and Methods

Male Wistar rats underwent 180 minutes of infrarenal aortic occlusion with 4, 24 and 72 hours of reperfusion. Postconditioning (10 sec. reocclusion / 10 sec. perfusion in 6 cycles) was applied in one group of each reperfusion time. Blood, urine, and histological (muscle, lung, kidney and liver) samples were collected at the postischemic 4th, 24th, and 72th hour.

Results

The early inflammatory response (TNFa, free radicals) and late local inflammation were reduced by posctonditioning significantly. Postconditioning was able to reduce the remote organ injury of lungs and kidneys, the morphological and laboratorial results showed significant difference between the postconditioning and the control group in these two organs. The method's positive effect on remote organ injury remained long-term.

Conclusion

Postconditioning seems to be an applicable process to reduce both local inflammatory and systemic complications of IR injury following vascular surgeries.

Radical surgery for pancreatic malignancy in the elderly

BACKGROUND

Improving life expectancy is associated with increasing incidence of pancreatic cancer. We reviewed morbidity and mortality in patients aged 65 years and older undergoing curative intent surgery in two centers in the Czech Republic.

METHODS

Data were retrieved by retrospective analysis of the medical records over the period 2000-2007. In total, 60 patients were included. The mean age was 71 years (median 70 years; range 65-85 years). Most patients (43, 72%) underwent hemipancreatoduodenectomy, combined in 4 with portomesenterial vessel resection. Twelve patients (20%) had distal pancreatectomy and 5 patients (8%) total pancreatectomy.

RESULTS

Overall morbidity was 28%. Only 10 patients (18%) developed serious surgical complications in terms of pancreatic leak (5, 8%), biliary leak (2, 3%), and intra-abdominal inflammatory collection (4, 7%). Four patients (6.6%) died within 30 days. The 1-year survival was 62.8%.

CONCLUSION

We can conclude that age per se is not a contraindication to surgery. Patient's overall general condition, co-existing co-morbidities, and ability to get over with any potential complications are more important. and IAP.

Small difference in international normalized ratio may yield a significant impact on prioritizing patients listed for liver transplantation

Priority for liver transplantation is currently based on the Model for End-stage Liver Disease (MELD) score. The aim of our study was to assess in detail the contribution of international normalized ratio (INR) differences for MELD scores because of interlaboratory variability. The samples from 92 cirrhotic patients were measured on different systems combining three coagulometers and three thromboplastin products to determine variations in INR and MELD score. The INR differences among the first four systems varied between 0 and 0.2, resulting in MELD differences of 0 to 2. The MELD scores of 92 patients changed only among 10 possible integers so that normally 2 to 10 patients shared the same MELD value. In some cases, one MELD score difference resulted in a 10 superpositioning on the waiting list. Including one more system (mechanical vs optical) into our investigations achieved a five MELD difference. Supposing an extreme situation where one patient competes with his or her lowest, all the other with their highest possible score (and visa versa), the difference may be even 20 positions, overturning the complete waiting list. In conclusion substantial interlaboratory differences in MELD score have profound clinical consequences.