Effectiveness of primary percutaneous coronary intervention for acute ST-elevation myocardial infarction from a 5-year single-center experience

Primary percutaneous coronary intervention (PCI) is currently viewed as the preferred reperfusion strategy in patients with ST-elevation acute myocardial infarction (STEMI). This method was introduced in our hospital in 2000. From January 1, 2000, to December 31, 2004, a total of 2,393 consecutive patients with STEMI were admitted (27% transferred from 9 non-PCI hospitals and 31 prehospital emergency units/outpatient clinics). Of these patients, 1,666 (70%) underwent urgent coronary angiography and primary PCI. Platelet glycoprotein llb/llla inhibitors were used in 40% and stent placement, in 78%. Postprocedural Thrombolysis In Myocardial Infarction (TIMI) 3 flow was documented in 86%. Intra-aortic balloon counterpulsation was used in 6%; mechanical ventilation, in 8.6%; and inotropic drugs/vasopressors, in 15.8%. Mortality rates in patients with Killip's class I or II ranged from 1% to 4.9% without negative influence of ischemic time. In patients with Killip's class III or IV, mortality rates increased from 18% to 54% with increasing ischemic delay up to 6 hours (p = 0.06) and remained at around 40% afterward. Independent predictors of mortality were age (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.01 to 1.64, p = 0.04), resuscitated cardiac arrest (OR 2.44, 95% CI 1.18 to 5.05, p = 0.02), and postprocedural TIMI flow (OR 0.31, 95% CI 0.16 to 0.59). Overall mortality rates of patients who underwent a primary PCI strategy from 2000 to 2004 were significantly lower than in the control group of 152 consecutive patients who underwent thrombolysis from 1995 to 1996 (6.2% vs 16.4%; p <0.001). In conclusion, introduction of a primary PCI strategy significantly decreased hospital mortality in our unselected group of patients with STEMI compared with the thrombolytic era. Our study further emphasized the importance of shortening myocardial ischemic time, particularly in the presence of severe heart failure on admission.     

Slowing down as an early warning signal for abrupt climate change

In the Earth's history, periods of relatively stable climate have often been interrupted by sharp transitions to a contrasting state. One explanation for such events of abrupt change is that they happened when the earth system reached a critical tipping point. However, this remains hard to prove for events in the remote past, and it is even more difficult to predict if and when we might reach a tipping point for abrupt climate change in the future. Here, we analyze eight ancient abrupt climate shifts and show that they were all preceded by a characteristic slowing down of the fluctuations starting well before the actual shift. Such slowing down, measured as increased autocorrelation, can be mathematically shown to be a hallmark of tipping points. Therefore, our results imply independent empirical evidence for the idea that past abrupt shifts were associated with the passing of critical thresholds. Because the mechanism causing slowing down is fundamentally inherent to tipping points, it follows that our way to detect slowing down might be used as a universal early warning signal for upcoming catastrophic change. Because tipping points in ecosystems and other complex systems are notoriously hard to predict in other ways, this is a promising perspective.     

Spontaneous rupture of a hepatic cystadenoma and cystadenocarcinoma: report of two cases

Hepatobiliary cystadenomas and cystadenocarcinomas are rare tumors. Differentiating between these tumors and benign hepatic cysts may be difficult. Because of their rarity, diagnosis is often delayed and may result in inaccurate treatment, resulting in unnecessary morbidity and mortality. The purpose of this report is to draw attention to these entities and their complications. We report on two cases with spontaneous rupture of hepatobiliary cystadenoma and cystadenocarcinoma cysts, initially treated as simple hepatic cysts by aspiration, or by aspiration combined with sclerotherapy. The spontaneous rupture of the cysts appeared years after the initial treatment of the cysts, leading in one case to a prolonged stay in an intensive care unit. In both cases, a formal liver resection was carried out and microscopic investigations revealed a mucinous cystadenocarcinoma and cystadenoma. In conclusion, although hepatobiliary cystadenomas and cystadenocarcinomas are rare findings, they should not be forgotten in the diagnostic workshop when examining patients with hepatic cysts. If hepatobiliary cystadenomas and cystadenocarcinomas cannot be excluded following radiological imaging, surgery is recommended.     

Efficacy and impact of monophasic versus biphasic countershocks for transthoracic cardioversion of persistent atrial fibrillation

This report compares the cumulative efficacy of cardioversion and skeletal muscle injury after either damped sine wave monophasic or truncated exponential biphasic transthoracic cardioversion of persistent atrial fibrillation. The trial sought to refute the null hypothesis of therapeutic equivalence between monophasic and biphasic waveforms. Results of the study reveal similar cumulative efficacy of waveforms and greater levels of skeletal muscle damage when patients are younger and male, and when monophasic waveforms are used.     

Antitumor activity of novel <Emphasis Type="Italic">N</Emphasis>-sulfonylpyrimidine derivatives on the growth of anaplastic mammary carcinoma in vivo

Purpose: The purpose of this study was to investigate in vivo antitumor activity of newly synthesized N-sulfonylpyrimidine derivatives 1-(p-toluenesulfonyl)cytosine (4H), 1-(p-toluenesulfonyl)cytosine hydrochloride (4H×HCl) and zinc(II) complex of 1-(p-toluenesulfonyl)cytosine (4K). Materials and methods: In order to do that we have used mouse anaplastic mammary carcinoma (AMCa). Tumor cells (10⁶) in a volume of 0.02 ml were transplanted into the thigh of the right hind leg of CBA mice. All compounds were dissolved in distilled water immediately before injecting to animals. Results: Antitumor effect of these compounds depends on drug doses and time interval between tumor transplantation and drug application. Further the efficacy of these compounds depends on number of drug injections, i. e. whether drug was given in single or in multiple doses. Multiple doses of 400 mg/kg of 1-(p-toluenesulfonyl)cytosine (4H) showed good antitumor effect when applied on day 1, 3, 5, 7 and 9 after tumor transplantation. Still good but slightly lower antitumor effect was also achieved when that compound was given in a single dose (1,200 mg/kg) on day 1 after tumor transplantation. The longest period of tumor growth time was obtained after application of 1-(p-toluenesulfonyl)cytosine hydrochloride (4H×HCl) given as a single dose (300 mg/kg) on day 1 or on day 6 after tumor implantation. However, antitumor effect of zinc(II) complex of 1-(p-toluenesulfonyl)cytosine (4K) was very strong when 300 mg/kg was given on day 1 or day 6, while this effect was slightly lower when drug (200 mg/kg/inj) was given on day 1, 3, 5, 7 and 9 or on day 6, 8, 10, 12 and 14. Conclusion: In this work it has been found that N-1-sulfonylcytosine derivatives have strong antitumor activity against mouse mammary carcinoma which is a good reason for further research of these compounds both in experimental and preclinical studies.     

Altered NKG2D function in NK cells induced by chronic exposure to NKG2D ligand-expressing tumor cells

NKG2D is an activation receptor that allows natural killer (NK) cells to detect diseased host cells. The engagement of NKG2D with corresponding ligand results in surface modulation of the receptor and reduced function upon subsequent receptor engagement. However, it is not clear whether in addition to modulation the NKG2D receptor complex and/or its signaling capacity is preserved. We show here that the prolonged encounter with tumor cell-bound, but not soluble, ligand can completely uncouple the NKG2D receptor from the intracellular mobilization of calcium and the exertion of cell-mediated cytolysis. However, cytolytic effector function is intact since NKG2D ligand-exposed NK cells can be activated via the Ly49D receptor. While NKG2D-dependent cytotoxicity is impaired, prolonged ligand exposure results in constitutive interferon gamma (IFNgamma) production, suggesting sustained signaling. The functional changes are associated with a reduced presence of the relevant signal transducing adaptors DNAX-activating protein of 10 kDa (DAP-10) and killer cell activating receptor-associated protein/DNAX-activating protein of 12 kDa (KARAP/DAP-12). That is likely the consequence of constitutive NKG2D engagement and signaling, since NKG2D function and adaptor expression is restored to normal when the stimulating tumor cells are removed. Thus, the chronic exposure to tumor cells expressing NKG2D ligand alters NKG2D signaling and may facilitate the evasion of tumor cells from NK cell reactions.     

New experimental melting properties as access for predicting amino-acid solubility

The properties of melting are required for the prediction of solubility of solid compounds. Unfortunately, direct determination of the enthalpy of fusion and melting temperature by using conventional DSC or adiabatic calorimetry is often not possible for biological compounds due to decomposition during the measurement. To overcome this, fast scanning calorimetry (FSC) with scanning rates up to 2 × 10⁴ K s⁻¹ was used in this work to measure the melting parameters for l-alanine and glycine. The enthalpy of fusion and melting temperature (extrapolated to zero heating rate) were Δ_fusH = (22 ± 5) kJ mol⁻¹ and T_fus = (608 ± 9) K for l-alanine, and Δ_fusH = (21 ± 4) kJ mol⁻¹ and T_fus = (569 ± 7) K for glycine. These melting properties were used in the modeling framework PC-SAFT to predict amino-acid solubility in water. The pure-component PC-SAFT parameters and one binary parameter were taken from literature, in which these parameters were fitted to solubility-independent thermodynamic properties such as osmotic coefficients or mixture densities. It was shown that this allowed accurately predicting amino-acid solubility in water over a broad temperature range. The combined methodology of PC-SAFT and FSC proposed in this work opens the door for predicting solubility of molecules that decompose before melting.

New experimental melting properties combined with PC-SAFT allow quantitative solubility predictions of amino acids in water.