Association of mitochondrial DNA copy number with metabolic syndrome and type 2 diabetes in 14 176 individuals

BACKGROUND

Mitochondria play an important role in cellular metabolism, and their dysfunction is postulated to be involved in metabolic disturbances. Mitochondrial DNA is present in multiple copies per cell. The quantification of mitochondrial DNA copy number (mtDNA-CN) might be used to assess mitochondrial dysfunction.

OBJECTIVES

We aimed to investigate the cross-sectional association of mtDNA-CN with type 2 diabetes and the potential mediating role of metabolic syndrome.

METHODS

We examined 4812 patients from the German Chronic Kidney Disease (GCKD) study and 9364 individuals from the Cooperative Health Research in South Tyrol (CHRIS) study. MtDNA-CN was measured in whole blood using a plasmid-normalized qPCR-based assay.

RESULTS

In both studies, mtDNA-CN showed a significant correlation with most metabolic syndrome parameters: mtDNA-CN decreased with increasing number of metabolic syndrome components. Furthermore, individuals with low mtDNA-CN had significantly higher odds of metabolic syndrome (OR = 1.025; 95% CI = 1.011-1.039, P = 3.19 × 10-4 , for each decrease of 10 mtDNA copies) and type 2 diabetes (OR = 1.027; 95% CI = 1.012-1.041; P = 2.84 × 10-4 ) in a model adjusted for age, sex, smoking and kidney function in the meta-analysis of both studies. Mediation analysis revealed that the association of mtDNA-CN with type 2 diabetes was mainly mediated by waist circumference in the GCKD study (66%) and by several metabolic syndrome parameters, especially body mass index and triglycerides, in the CHRIS study (41%).

CONCLUSIONS

Our data show an inverse association of mtDNA-CN with higher risk of metabolic syndrome and type 2 diabetes. A major part of the total effect of mtDNA-CN on type 2 diabetes is mediated by obesity parameters.

Long-term outcome of persons with diabetic and non-diabetic neuro-osteoarthropathy after foot correction using external fixation

AIM

Diabetic neuro-osteoarthropathy (Charcot foot) is a serious form of diabetic foot syndrome, often leading to severe deformity of the foot and subsequently to ulcers and osteomyelitis. The aim of this retrospective study was to determine the success rate and long-term outcomes for a Charcot foot operation using external fixation in 115 individuals who underwent surgery between July 2008 and December 2012.

METHODS

Some 115 consecutive persons, 78 (68%) men and 37 (32%) women, were enrolled in this study. The eligibility criterion for this retrospective study was reconstructive foot surgery using a Hoffmann II external fixator in diabetic and non-diabetic neuro-osteoarthropathy. The main examination parameters in the follow-up were walking ability, amputation and mortality. Average follow-up was 5.7 (± 3.2) years.

RESULTS

Ninety-seven per cent of people were able to walk after the operation with bespoke shoes or an orthosis. At follow-up, 77% were able to walk and 51% were fully mobile even outside the home. Subsequent amputations were performed in 29 individuals (26%), with 17 (15%) minor and 12 (11%) major amputations. Forty-seven individuals died before follow-up, the majority (53%) from cardiovascular events. Average survival time post surgery was 4.5 (± 2.9) years.

CONCLUSION

Reconstruction surgery using external fixation is a very useful method for maintaining walking ability in the case of conservatively non-treatable diabetic and non-diabetic neuro-osteoarthropathy. Individuals with severe Charcot foot disease had a low rate of major amputations. Osteomyelitis was the main reason for major amputations.

Mitochondrial DNA copy number is associated with all-cause mortality and cardiovascular events in patients with peripheral arterial disease

BACKGROUND

Dysfunctional mitochondria have an influence on inflammation and increased oxidative stress due to an excessive production of reactive oxygen species. The mitochondrial DNA copy number (mtDNA-CN) is a potential biomarker for mitochondrial dysfunction and has been associated with various diseases. However, results were partially contrasting which might have been caused by methodological difficulties to quantify mtDNA-CN.

OBJECTIVE

We aimed to investigate whether mtDNA-CN is associated with peripheral arterial disease (PAD) as well as all-cause mortality and cardiovascular events during seven years of follow-up.

METHODS

A total of 236 male patients with PAD from the Cardiovascular Disease in Intermittent Claudication (CAVASIC) study were compared with 249 age- and diabetes-matched controls. MtDNA-CN was measured with a well-standardized plasmid-normalized quantitative PCR-based assay determining the ratio between mtDNA-CN and nuclear DNA.

RESULTS

Individuals in the lowest quartile of mtDNA-CN had a twofold increased risk for PAD which, however, was no longer significant after adjusting for leukocytes and platelets. About 67 of the 236 patients had already experienced a cardiovascular event at baseline and those in the lowest mtDNA-CN quartile had a 2.34-fold increased risk for these events (95% CI 1.08-5.13). During follow-up, 37 PAD patients died and 66 patients experienced a cardiovascular event. Patients in the lowest mtDNA-CN quartile had hazard ratios of 2.66 (95% CI 1.27-5.58) for all-cause-mortality and 1.82 (95% CI 1.02-3.27) for cardiovascular events compared with the combined quartile 2-4 (adjusted for age, smoking, CRP, diabetes, prevalent cardiovascular disease, leukocytes and platelets).

CONCLUSION

This investigation supports the hypothesis of mitochondrial dysfunction in peripheral arterial disease and shows an association of low mtDNA-CNs with all-cause-mortality and prevalent and incident cardiovascular disease in PAD patients with intermittent claudication.

Lack of flow mediated dilation and enhanced angiotensin II-induced constriction in skeletal muscle arterioles of lupus-prone autoimmune mice

Systemic lupus erythematosus (SLE) is associated with disturbances in the microcirculation of various tissues, yet the nature of arteriolar dysfunction has not been characterized. Thus, changes in diameter of isolated, pressurized skeletal muscle arterioles of mice with systemic autoimmune disease (lupus prone, MRL/lpr four-month old female) and control (MRL) mice were investigated by video-microscopy. Arteriolar responses to changes in intraluminal pressure, flow, and to vasoactive agents with known mechanisms of action were compared. The active and passive (in Ca2+ free solution) diameter of MRL/lpr arterioles were not significantly different compared to MRL and morphometric changes were not apparent. Compared to MRL mice the endothelium-dependent dilations to increase in flow, acetylcholine and bradykinin were markedly reduced in arterioles of MRL/lpr mice. Endothelium-independent dilations to sodium-nitroprusside and adenosine were similar in MRL and MRL/lpr arterioles. Furthermore, angiotensin II elicited greater constrictions in MRL/lpr arterioles, whereas serotonin-induced constrictions were similar in both groups. Thus, in arterioles of MRL/lpr mice endothelium-dependent dilator mechanisms are impaired and constriction to angiotensin II is enhanced, suggesting specific alterations in the vasomotor function of microvessels that are likely contribute to the disturbance of skeletal muscle blood flow observed in systemic lupus erythematosus.

Trained clinical nurse specialists proficiently obtain bone marrow aspirates and trephine biopsies in a nearly painless procedure--a prospective evaluation study

Patients often experience bone marrow examinations (BMEs) as frightening and painful. Varying operators and uncertainty about who will perform the BME worsen their anxiety. In our study, clinical nurse specialists (CNSs) were trained to perform BMEs to ensure continuity and to test the feasibility, patient satisfaction, and biopsy quality. This exploratory evaluation assessed 574 BMEs at our tertiary center between January 2012 and February 2013, 398 BMEs performed by CNS and 176 by physicians. Our aims were to determine whether BMEs by CNS yield results similar to those of physicians, analyzing (1) patient satisfaction with the BME (a) consent and (b) performance, (2) induced pain, and (3) quality of aspirates and length of trephine biopsies. When performed by CNS, 100 % of the patients were satisfied with the consent procedure and 99 % with the BME performance (physicians 99 and 91 %, respectively). The median pain score was low when both CNS and physicians performed the BME, with no or only mild pain in 92 and 76 % of patients, respectively. Bone marrow (BM) aspirates by CNS and physicians were assessed as technically evaluable in ~70 %; moreover, the median length of trephine biopsies was similar when performed by CNS or physicians with 12 and 13 mm, respectively. In conclusion, BMEs conducted by motivated CNS and within a structured training program are feasible and yield equal outcomes compared to physicians. The use of adequate pain management during BMEs by trained and experienced operators results in an extremely rare use of sedatives, low pain scores, and high patient satisfaction.

Galanin modulates human and murine neutrophil activation in vitro

AIMS

Polymorphonuclear neutrophils are key players in innate immunity. The innate immune system needs to be tightly controlled to ensure proper activation but also no overactivation. Galanin has been shown to regulate inflammatory reactions, and therefore, we aimed to elucidate the expression of galanin and its three receptors (GAL1 -GAL3 ) in polymorphonuclear neutrophils and to evaluate whether galanin exerts direct or indirect effects on human and murine polymorphonuclear neutrophils.

METHODS

Human peripheral polymorphonuclear neutrophils were isolated from fresh blood of healthy donors, and murine polymorphonuclear neutrophils were isolated from bone marrow of C57BL/6N mice. Gene expression was evaluated by qRT-PCR. As a marker for polymorphonuclear neutrophil activation, CD11b integrin surface expression was measured by FACS analysis. Furthermore, a label-free technology measuring ligand-induced dynamic mass redistribution was used to evaluate the response of polymorphonuclear neutrophils to galanin.

RESULTS

GAL2 receptor expression was found in both human and murine polymorphonuclear neutrophils, galanin and GAL3 receptor were exclusively expressed in murine bone marrow polymorphonuclear neutrophils, and GAL1 receptor was not detectable in polymorphonuclear neutrophils of either species. Galanin treatment was not able to induce CD11b integrin surface expression or dynamic mass redistribution in human polymorphonuclear neutrophils and murine bone marrow polymorphonuclear neutrophils. However, galanin treatment significantly enhanced the response of polymorphonuclear neutrophils of both species to interleukin-8.

CONCLUSION

Galanin can be regarded as an immunomodulatory peptide as it can sensitize polymorphonuclear neutrophils towards pro-inflammatory cytokines in humans and mice.

Antiplatelet effect of acetylsalicylic acid, metamizole and their combination - in vitro and in vivo comparisons

BACKGROUND

Acetylsalicylic acid (ASA) plays an important role in the treatment and prevention of cardiovascular diseases. Metamizole (MET) is an analgesic and antipyretic medicine, it is not used as an antiplatelet drug.

OBJECTIVES

We aimed to examine the antiplatelet effect of MET and the possible interactions between the drugs.

METHODS

In our in vitro investigations different concentrations of ASA and MET solutions were added to blood. To examine the interactions MET and ASA were added together. In our in vivo crossover study intravenous MET, oral ASA or both drugs together were administered. Epinephrine and adenosine-diphosphate induced platelet aggregation was determined by optical aggregometry.

RESULTS

Epinephrine-induced aggregation was completely inhibited in all ASA and MET concentrations in vitro. Lower, ineffective concentration of MET prevented the antiplatelet effect of ASA. The inhibition was completely restored when higher concentration of ASA was used or when ASA was added first. Our in vivo study showed that in the MET group rapid onset of inhibition was developed and there was no inhibition after one day. In the ASA group platelet aggregation decreased slowly but still had significant inhibitory effect after 72 hours. Combined therapy showed similar changes to the MET group.

CONCLUSION

Antiplatelet effect of MET and ASA did not differ significantly in vitro. The observations may indicate a competitive interaction between the two drugs. The in vivo experiments showed that intravenously administered MET is an effective antiplatelet drug and can be considered as a therapeutic alternative, when ASA cannot be used in oral form.

Elevated vascular level of ortho-tyrosine contributes to the impairment of insulin-induced arterial relaxation

Previous studies have shown that in diabetes mellitus, insulin-induced relaxation of arteries is impaired and the level of ortho-tyrosine (o-Tyr), an oxidized amino acid is increased. Thus, we hypothesized that elevated vascular level of o-Tyr contributes to the impairment of insulin-induced vascular relaxation. Rats were fed with o-Tyr for 4 weeks. Insulin-induced vasomotor responses of isolated femoral artery were studied using wire myography. Vascular o-Tyr content was measured by HPLC, whereas immunoblot analyses were preformed to detect eNOS phosphorylation. Sustained oral supplementation of rats with o-Tyr increased the content of o-Tyr in the arterial wall and significantly reduced the relaxations to insulin. Sustained supplementation of cultured endothelial cells with o-Tyr increased the incorporation of o-Tyr and mitigated eNOS Ser (1 177) phosphorylation to insulin. Increasing arterial wall o-Tyr level attenuates insulin-induced relaxation - at least in part - by decreasing eNOS activation. Elevated level of o-Tyr could be an underlying mechanism for vasomotor dysfunction in diabetes mellitus.

Hydrogen peroxide via thromboxane A2 receptors mediates myogenic response of small skeletal muscle veins in rats

We aimed to test two hypotheses: (1) isolated small veins develop substantial myogenic tone in response to elevation of intraluminal pressure, (2) H2O2 contributes to the mediation of myogenic response via activation of arachidonic acid (AA) cascade and release constrictor prostaglandins.

METHODS

Small veins were isolated from gracilis muscle of male rats, then cannulated. Changes of diameter to increases in intraluminal pressure, H2O2 and arachidonic acid in the presence and absence of various inhibitors were measured by videomicroscope and microangiometer. At the end of experiments the passive diameter were obtained in Ca2+ -free PSS solution.

RESULTS

Isolated rat gracilis muscle small veins developed a substantial myogenic tone in response to increases in intraluminal pressure (1-12 mmHg). Calculated maximum myogenic tone was 70 ± 5% at 10 mmHg. Presence of catalase or indomethacin or SQ 29,548 reduced significantly the pressure-induced myogenic response. Also, H2O2 (10-9-10-5 M) and arachidonic acid (10-7-10-4 M) elicited concentration dependent constrictions, which were inhibited by the presence of indomethacin or SQ 29,548.

CONCLUSION

We propose that both myogenic response and pressure-induced release of H2O2 play important roles in regulating the vasomotor function of venules both in physiological and pathological conditions.

Increase in insulin-induced relaxation of consecutive arterial segments toward the periphery: Role of vascular oxidative state

RATIONALE

The oxidative state has been implicated in the signaling of various vasomotor functions, yet its role regarding the vasomotor action of insulin is less known.

OBJECTIVE

To investigate the insulin-evoked relaxations of consecutive arterial segments of different oxidative state and the role of extracellular signal-regulated kinase (ERK) pathway.

METHODS AND RESULTS

The oxidative state, as assessed by the level of ortho-tyrosine, was higher in the thoracic aorta of rats than in the abdominal aorta, and was the lowest in the femoral artery. The vasomotor function of vessels of same origin was studied using a small-vessel myograph. Insulin-induced relaxations increased toward the periphery (i.e., thoracic < abdominal < femoral). Aortic banding and hydrogen peroxide/aminotriazole increased the oxidative state of the thoracic aorta that was accompanied by ERK activation and decreased relaxation to insulin, and vice versa, acutely lowered oxidative state by superoxide dismutase/catalase improved relaxation. In contrast, insulin-induced relaxation of the femoral artery could be enhanced with a higher oxidative state, and reduced with a lower state.

CONCLUSIONS

Oxidative state of vessels modulates the magnitude of vasomotor responses to insulin, which appears to be mediated via the ERK signaling pathway.

P16INK4A immunohistochemistry for detection of human papilloma virus-associated penile squamous cell carcinoma is superior to in-situ hybridization

We evaluated p16INK4A as a reliable option to detect human papilloma virus (HPV) DNA in penile tumor specimens. Formalin-fixed paraffin embedded samples of 26 patients with penile cancer and another 18 cases with non-tumorigenic lesions were stained by three different widely used commercially available chromogenic in-situ hybridization assays high-risk HPV CISH Y1443 (Genpoint, DAKO), pan HPV CISH Y1404 (Genpoint, DAKO), INFORM HPV III (Ventana, Tucson, Arizona) and p16INK4A immunohistochemistry, then compared to the known gold standard polymerase chain reaction detecting HPV 16, 18, 31, and 33. Immunoreactivity for p16INK4A was evaluated by using a 4-tiered (0, 1, 2, and 3) pattern based system. 19 cases were positive for p16INK4A, 13 of which showed a continuous transepithelial staining (pattern 3). Pan HPV ISH showed positivity in 9 cases, high-risk HPV ISH in 7 cases and INFORM HPVIII ISH in 7 cases. p16INK4A IHC pattern 3 versus pattern 0, 1 and 2 exhibited a specificity and positive predictive value of 100 percent, with a sensitivity and negative predictive value of 72 and 62 percent, respectively, which was much better than all HPV in-situ hybridization methods referred to polymerase chain reaction. p16INK4A seems to be a superior marker for the detection of HPV-associated penile squamous cell carcinoma compared to CISH tests, but is not recommend for the detection of non-tumorigenic lesions, where PCR should be used for the initial assessment.

Clinical practice recurrent severe obscure gastro intestinal-bleeding in a 20 year old man

Morbus Osler-Weber-Rendu syndrome also known as Hereditary hemorrhagic telangiectasia (HHT) and Meckel's diverticulum is a rare combination disorder. Our case presented with the recurrent obscure gastrointestinal (GI) bleeding for several years. He came with a massive active lower gastrointestinal bleeding. Ultimatively, he underwent an exploratory laparotomy along with intraoperative colonoscopy. A Meckel's diverticulum in combination with multiple erosions was found as a probable cause of the massive gastrointestinal bleeding. An ileo-caeacal resection had been performed and by the pathologist multiple telangiectasias in the resected ileum were established. Blood was sent for genetics and was negative for ENG, ALK-1, and SMAD-4 genes. The patient was discharged after 10 days from time of admission and is under regular follow up without any further bleeding. In this case, despite sophisticated techniques for investigations the cause of the GI-bleeding with several esophagogastroduodenoscopies and colonoscopies, mesenteric angiography and finally an oral double balloon enteroscopy was misdiagnosed till the intra operative endoscopy showed a middle GI-bleeding. The management for obscure GI-bleeding is discussed for countries with lower medical facilities like Nepal in our case with Morbus Osler-Weber-Rendu syndrome.

Overview of large animal myocardial infarction models (review)

There are several experimental models for the in vivo investigation of myocardial infarction (MI) in small (mouse, rat) and large animals (dog, pig, sheep and baboons). The application of large animal models raises ethical concerns, the design of experiments needs longer follow-up times, requiring proper breeding and housing conditions, therefore resulting in higher cost, than in vitro or small animal studies. On the other hand, the relevance of large animal models is very important, since they mostly resemble to human physiological and pathophysiological processes. The first main difference among MI models is the method of induction (open or closed chest, e.g. surgical or catheter based); the second main difference is the presence or absence of reperfusion. The former (i.e. reperfused MI) allows the investigation of reperfusion injury and new catheter based techniques during percutaneous coronary interventions, while the latter (i.e. nonreperfused MI) serves as a traditional coronary occlusion model, to test the effects of new pharmacological agents and biological therapies, as cell therapy. The reperfused and nonreperfused myocardial infarction has different outcomes, regarding left ventricular function, remodelling, subsequent heart failure, aneurysm formation and mortality. Our aim was to review the literature and report our findings regarding experimental MI models, regarding the differences among species, methods, reproducibility and interpretation.

[Oncological patients' decision making processes concerning their pain medication at home: a qualitative secondary analysis]

Unrelieved pain affects up to 75 % of cancer patients. Possible reasons for the undertreatment of pain are, amongst others, patient-related barriers towards cancer pain management. However the way patients decide on the use of analgesics remains unclear. The purpose of this qualitative study was to explore decision-making processes of four women and four men with diverse cancers concerning their pain medications. Audiotaped protocols of the 10-week-intervention and interviews of the PEINCA-pilot study provided data for a secondary analysis. This pilot study was conducted at a comprehensive cancer centre in Germany to test the German version of a cancer pain self-management intervention to enhance oncology patients' pain self-management for the first time. The data of purposively selected patients were analysed using content analysis. The results showed that these patients were very ambivalent about their analgesic use. The need to relieve severe pain conflicted with the desire to avoid opioids at any price. Decisions were reconsidered and overturned even after good experiences with analgesics. This study seems to provide a first look into decision-making processes over 10 weeks during a self-management education. Individually tailored counselling by a professional within the education programme helped the patients adopt new attitudes towards analgesics and gradually reduce their pain levels. Previous experiences of the patients and their possible ambivalence towards analgesics should be considered in a pain therapy, and patients should be coached by professionals.

[Diabetic osteoarthropathy: problems and complications in foot surgery]

Charcot neuroarthropathy is one of the most serious manifestations of the diabetic foot syndrome and the multifaceted disease pattern requires interdisciplinary cooperation. Problems may arise even if the diagnosis is made early and lack of pain may mislead to the assumption of an infectious or traumatic event. With respect to operative therapy the characteristics of polyneuropathy and altered bone metabolism have to be taken into account. Rehabilitation, in particular, differs from the guidelines for trauma patients. In the face of high complication risks substantial improvement of function must be the goal for operative treatment.

Norovirus outbreaks linked to oyster consumption in the United Kingdom, Norway, France, Sweden and Denmark, 2010

This paper reports on several simultaneous outbreaks of norovirus infection linked to the consumption of raw oysters. Since January 2010, 334 cases in 65 clusters were reported from five European countries: the United Kingdom, Norway, France, Sweden and Denmark. The article describes the available epidemiological and microbiological evidence of these outbreaks.

Norovirus outbreaks linked to oyster consumption in the United Kingdom, Norway, France, Sweden and Denmark, 2010

This paper reports on several simultaneous outbreaks of norovirus infection linked to the consumption of raw oysters. Since January 2010, 334 cases in 65 clusters were reported from five European countries: the United Kingdom, Norway, France, Sweden and Denmark. The article describes the available epidemiological and microbiological evidence of these outbreaks.

Thromboxane A(2) contributes to the mediation of flow-induced responses of skeletal muscle venules: role of cyclooxygenases 1 and 2

BACKGROUND

It has been shown that increases in intraluminal flow elicit dilation in venules, but the mediation of response is not yet clarified. We hypothesized that - in addition to nitric oxide (NO) and dilator prostaglandins (PGI(2)/ PGE(2)) - thromboxane A(2) (TxA(2)) contributes to the mediation of flow-induced responses of venules.

METHODS AND RESULTS

Isolated rat gracilis muscle venules (259 +/- 11 microm at 10 mm Hg) dilated as a function of intraluminal flow, which was augmented in the presence of the TxA(2) receptor antagonist SQ 29,548 or the TxA(2) synthase inhibitor ozagrel. In the presence of SQ 29,548, indomethacin or Nomega-nitro-L-arginine methyl-ester decreased flow-induced dilations, whereas in their simultaneous presence dilations were abolished. The selective cyclooxygenase (COX) 1 inhibitor SC 560 reduced, whereas the selective COX-2 inhibitor NS 398 enhanced flow-induced dilations. Immunohistochemistry showed that both COX-1 and COX-2 are present in the wall of venules.

CONCLUSION

In skeletal muscle venules, increases in intraluminal flow elicit production of constrictor TxA(2), in addition to the dilator NO and PGI(2)/PGE(2), with an overall effect of limited dilation. These mediators are likely to have important roles in the multiple feedback regulation of wall shear stress in venules during changes in blood flow velocity and/or viscosity.

Human papillomavirus type 26 infection causing multiple invasive squamous cell carcinomas of the fingernails in an AIDS patient under highly active antiretroviral therapy

Squamous cell carcinoma (SCC) of the nail unit is a rare disorder. An association with high-risk genital human papillomavirus (HPV) infection has been reported. We report a 28-year-old human immunodeficiency virus (HIV)-infected bisexual man who had multiple invasive SCC of the fingers, infected with the rare type HPV 26. Classification of HPV 26 as high- or intermediate-risk type has been uncertain, due to its rare presence in cervical cancer. Despite successful treatment with highly active antiretroviral therapy (HAART), the patient developed extensive hyperkeratotic nailbed proliferations of all fingers. Tumours were refractory to treatment and invaded into adjacent tissues. X-rays of the hands demonstrated bone invasion, necessitating amputation of distal phalanges of several fingers. Histologically, highly differentiated preinvasive and invasive verrucous SCCs were identified. Molecular DNA typing identified HPV 26 in the SCCs and in some premalignant lesions. By in situ hybridization HPV 26 DNA was detected in numerous tumour cells, indicating productive infection with high-level amplification of the viral genome. In the remaining proliferations, high-risk HPV type 58, cutaneous HPVs and a putative new HPV type were identified. HPV 26 infection appears to be causally involved in the development of SCC of the nail unit in this immunosuppressed patient. Timely evaluation of chronic verrucous nailbed tumours is recommended, especially in immunocompromised patients. Identification of HPV 26, besides known high-risk HPV types, may identify patients at risk for developing SCC of the nailbed and possibly at other locations.

Livin and Bcl-2 expression in high-grade osteosarcoma

AIMS

The evaluation of prognosis in patients with osteosarcoma is limited to clinical parameters. Although numerous molecular markers have been studied, none are currently in routine clinical use. The aim of this study was to determine if Livin and Bcl-2, acting as antiapoptotic proteins through different mechanisms, are expressed in osteosarcoma, and whether they can be used as prognostic markers in human osteosarcoma.

METHODS

Tumor specimens of 29 patients with high-grade central osteosarcoma, with complete clinical follow-up for a minimum of 5 years, were studied. The localization and distribution of Livin and Bcl-2 were investigated using immunohistochemistry. Results were correlated with the histological response to chemotherapy, 5-year disease-free and 5-year overall survival.

RESULTS

Bcl-2 was expressed only in the cytoplasm of 16/29 cases and there was no statistically significant correlation between expression and any of the studied parameters. Livin was detected in 17/29 cases, in the cytoplasm of all 17 and in the nucleus of only 3 cases. Nuclear expression was significantly correlated with a decreased overall survival (P < 0.0002) compared with those patients without nuclear expression.

CONCLUSIONS

The results of this study indicate that Bc1-2 and Livin are highly expressed in osteosarcoma cells and that possibly, the evaluation of nuclear Livin expression might be a useful prognostic marker in osteosarcoma.

Death in correctional facilities: opportunities for automated external defibrillation

BACKGROUND

Death due to cardiovascular disease occurs more frequently in prisons than the national average. Due to close surveillance 24 h/day, the ability to reach the patient within 3 min and time consuming access for the EMS crews, it was hypothesised that the deployment of automated external defibrillators (AEDs) might make improvements regarding Call-to-the-First-AED-Prompt (CTP) interval and formed the aim of this study.

METHODS

Our investigation was analysed on an intention to treat basis and conducted in a prospective, open and observational design. As the primary outcome, the CTP-intervals were compared to the arrival intervals of the EMS. As a secondary outcome, an analysis of all deceased inmates was described.

RESULTS

The average daily population of inmates in Austrian correctional facilities is 7714. During a period of 13 months, 10 instances in which an AED was activated and electrodes attached to a collapsed inmate, were reported. The CTP-interval (median+/-S.D.) was 2.3+/-1.6 S.D. min. It took the EMS 10.0+/-4.3 S.D. min. to arrive at the patient's side. Four out of 10 cases of cardiac arrest occurred due to myocardial infarction. Of 39 deceased inmates, a post mortem examination was completed in 34 cases. In 13 cases, cardiovascular disease was the cause of death.

DISCUSSION

The main finding was a four-fold reduction of the CTP-interval. This fact indicates the potential improvements which could be achieved with the deployment of AEDs. Our secondary objective revealed that death due to cardiovascular disease was found in a high proportion and could be considered to be a strong incentive to initiate programmes to counter cardiovascular death in prison.

[Management of upper limb deformities. Treatment concepts through the years]

The provision of aids and prostheses for patients with upper limb deficiencies has to be based on comprehensive knowledge in the field of orthopaedic technology. Taking into account the patient's complete background, evaluation of the possible functional benefit is mandatory in order to achieve good acceptance of a prosthesis in the long term. The extent of extremity "loss" and the remaining function of the deficient limb have an impact on the success of prosthetic fitting. Furthermore, there is a trend towards myoelectric prostheses, which seem to improve prosthetic acceptance. Bilateral congenital deficiency of the upper limbs cannot be equated with amputations. Most people affected do not push for a prosthesis, but should be provided with one, if the need arises. Decades of overuse of the deficient limbs often take their toll in terms of decreasing function as degenerative changes occur. As a consequence, artificial upper limbs may be obligatory to prevent loss of independence.

[Significance of microbial colonisation in materials for orthopaedic technology. New insights]

A great problem in the treatment of diabetes are infections of diabetic feet. A likely reservoir of microorganisms are contaminated orthopaedic materials. Insoles from 70 patients were examined for potential microbial colonisation. Commonly employed materials were contaminated in vitro under standardised conditions using known microorganisms. After treating with an alcoholic skin disinfectant, the organisms were counted semiquantitatively. In addition to pathogens, the surfaces showed mainly microorganisms present in the normal skin flora. In all materials tested, disinfection reduced the number of organisms by 4-5 log orders. It could be shown that simple disinfection (wiping) reduces the microorganisms present on orthopaedic materials to an acceptable number. Further studies are needed to determine whether this also reduces the incidence of diabetic skin and soft tissue infection.

Nitric oxide modulates the interaction of pressure-induced wall mechanics and myogenic response of rat intramural coronary arterioles

Interactions between the biomechanical characteristics and pressure-induced active response of coronary microvessels are still not well known. We tested the hypothesis that pressure-dependent biomechanical characteristics of the coronary vascular wall are modulated by the active myogenic response and local vasodilators. We have utilized data obtained previously in isolated rat intramural coronary arterioles (approximately 100 microm in diameter), in which the diameter was investigated as a function of intraluminal pressure (Szekeres et al.: J. Cardiovasc. Pharmacol., 43, 242-249, 2004). To characterize the magnitude of myogenic response, diameter was expressed as percent of passive diameter as a function of pressure (normalized diameter; ND). In addition, circumferential wall stress (WS) and incremental distensibility (ID) were calculated. In control conditions, after an initial increase between 0-30 mm Hg, ND decreased substantially as pressure increased from 30 to 150 mm Hg. Correspondingly, WS gradually increased as a function of pressure (from 0.3 +/- 0.03 to 34.7 +/- 4.4 kPa) exhibiting a plateau phase between 40-80 mm Hg. In contrast, ID decreased and reached negative values (min: -104.9 +/- 21.9 10(-6) m2/N at 50 mm Hg). Inhibition of nitric oxide (NO) synthase by L-NNA decreased basal diameter (approximately 35% at 2 mm Hg), eliminated pressure-induced changes in ND, reduced the slope of pressure-WS curve, and decreased ID at lower pressures. Simultaneous administration of L-NNA and adenosine (which restored initial diameter, i.e. length of smooth muscle) restored--in part--the pressure-induced reduction in ND, reversed the pressure-induced behavior of WS to control, but not that of ID. These results not only confirm that in coronary arterioles wall stress is regulated by the myogenic response, but also suggest that there is interplay between the mechanical behavior of the wall and the myogenic response. Furthermore, the presence of NO seems to be necessary for maintaining a higher distensibility of intramural coronary arterioles allowing increases in diameter to lower pressures, which then activate the myogenic mechanism resulting in constrictions and full development of myogenic tone, as indicated by the presence of negative slope of pressure-diameter curve in the presence of NO.