Site of origin and molecular substrate of atrioventricular junctional rhythm in the rabbit heart

During failure of the sinoatrial node, the heart can be driven by an atrioventricular (AV) junctional pacemaker. The position of the leading pacemaker site during AV junctional rhythm is debated. In this study, we present evidence from high-resolution fluorescent imaging of electrical activity in rabbit isolated atrioventricular node (AVN) preparations that, in the majority of cases (11 out of 14), the AV junctional rhythm originates in the region extending from the AVN toward the coronary sinus along the tricuspid valve (posterior nodal extension, PNE). Histological and immunohistochemical investigation showed that the PNE has the same morphology and unique pattern of expression of neurofilament160 (NF160) and connexins (Cx40, Cx43, and Cx45) as the AVN itself. Block of the pacemaker current, If, by 2 mmol/L Cs+ increased the AV junctional rhythm cycle length from 611+/-84 to 949+/-120 ms (mean+/-SD, n=6, P<0.001). Immunohistochemical investigation showed that the principal If channel protein, HCN4, is abundant in the PNE. As well as the AV junctional rhythm, the PNE described in this study may also be involved in the slow pathway of conduction into the AVN as well as AVN reentry, and the predominant lack of expression of Cx43 as well as the presence of Cx45 in the PNE shown could help explain its slow conduction.     

Assessing patient–caregiver communication in cancer—a psychometric validation of the Cancer Communication Assessment Tool (CCAT-PF) in a German sample

Purpose

The recently introduced Cancer Communication Assessment Tool (CCAT-PF) measures congruence in patient–caregiver communication and was initially validated in lung cancer patients. Contributing to a greater proportion of the variance in the conflict scores, primary caregivers were hypothesized to experience greater stress. For a detailed understanding of conflicting communication patterns of cancer-affected families, our study aimed for psychometric validation of the CCAT-PF in a sample covering heterogeneous tumor entities.

Methods

Subsequent to a cross-sectional survey of 189 pairs of cancer patients (31 % gastrointestinal, 34 % lung, and 35 % urological) and their caregivers’ exploratory factor analysis with principal component condensation and varimax rotation was conducted (response rate, 74.2 %). Reliability and construct validity were assessed calculating Cronbach’s α and Pearson correlation coefficients for CCAT-P and CCAT-F scales and related constructs, respectively.

Results

Cancer-related communication according to the CCAT-PF can be subdivided into four factors including the scales Disclosure, Limitation of treatment, Family involvement in treatment decisions, and Continuing treatment. Reliability ranged from α?=?.51–.68. The Disclosure scale, describing poor cancer-related communication of the patient, was correlated with patient’s distress (QSC-R10: r?=?.30, p?<?.0001), unmet needs in several areas (SCNS-SF-34: r?=?.25–.32, p?<?.001), and negatively with social/family well-being (FACT: r?=??0.31, p?<?.0001). Higher scores on the scale were significantly associated with considerable decrements in emotional well-being especially for caregivers perceiving patients’ disclosure as problematic.

Conclusions

The Disclosure scale originating from the CCAT-PF emerged as a short, valid, and reliable stand-alone instrument for identifying conflicting communication in patient–caregiver–dyads at risk.     

Leaching and VOC Emission Tests of Polymer Composites Produced from Post-Consumer Waste in Terms of Application in the Construction Sector

One of the existing priorities of the European Union is to search for rational waste management and to keep such waste in the economic cycle, while meeting the highest safety requirements. The paper presents the results of environmental tests of composites based on the polyethylene (rPE) and polypropylene (rPP) matrix and reinforced with cellulose fibres (newsprint, NP). Raw materials were obtained by recycling post-consumer waste such as beverage bottles and newsprint. The composites were tested for their potential use as materials in cladding panels and acoustic barriers. Given that normative documents for these products do not define specific environmental requirements, the composites were tested for the release of dangerous substances, such as anions of inorganic compounds, heavy metals, volatile organic compounds (VOCs), and their impact on the environment. A detailed in-depth analysis of the mechanisms of release of substances (diffusion, dissolution, surface leaching and depletion) from the rPP/NP composite into surface water, groundwater and soil was carried out. In turn, emission of VOCs from the rPE (low-density:high-density (LD:HD)—50:50) and rPE (LD:HD—30:70) composites into indoor air was also carried out. Raw materials in the form of granulates and loose cellulose fibres, used to produce the composites, were also tested for their environmental impact.     

Current pathogenetic aspects of hepatic encephalopathy and noncirrhotic hyperammonemic encephalopathy

Hepatic encephalopathy is a medical phenomenon that is described as a neuropsychiatric manifestation of chronic or acute liver disease that is characterized by psychomotor,intellectual and cognitive abnormalities with emotional/affective and behavioral disturbances.This article focuses on the underlying mechanisms of the condition and the differences between hepatic encephalopathy and noncirrhotic hyperammonemic encephalopathy.Hepatic encephalopathy is a serious condition that can cause neurological death with brain edema and intracranial hypertension.It is assumed that approximately 60%-80% of patients with liver cirrhosis develop hepatic encephalopathy This review explores the complex mechanisms that lead to hepatic encephalopathy.However,noncirrhotic hyperammonemic encephalopathy is not associated with hepatic diseases and has a completely different etiology.Noncirrhotic hyperammonemic encephalopathy is a severe occurrence that is connected with multiple pathogeneses.     

Assessment of platelet activation and phagocytic activity in gastric cancer patients

AIM: To assess the activation of platelets and their phagocytic activity in the course of gastric cancer. METHODS: Forty-three gastric cancer patients were recruited to the study. The patients were divided into 3 groups depending on tumor stage. Group E included 6 patients with early gastric cancer; group A included 18 patients with locally advanced cancer; and group M included 19 patients with metastatic cancer. The investigations were performed twice, prior to surgery and 12-14 d afterwards. RESULTS: The platelet count and the level of sP-selectin were found to increase with the disease progression. The level of sP-selectin was lowest in early cancer and was observed to increase after surgery in all the study patients. Irrespective of tumor stage, a statistically significant decrease was noted in the percentage of phagocytizing platelets and in the phagocytic index in gastric cancer patients as compared to healthy subjects. Despite increased platelet count and stimulation of thrombocytopoiesis, the phagocytic functions of blood platelets were markedly impaired. Tumor development seems to impair metabolic processes. CONCLUSION: A decreasing phagocytic activity can promote both inflammatory processes and cancer growth.     

Schwefelsäure-Vergiftung durch direkte Einführung der Säure ins Duodenum

Ohne Zusammenfassung     

Antiplatelet antibody predicts platelet desialylation and apoptosis in immune thrombocytopenia

Immune thrombocytopenia (ITP) is a bleeding disorder caused by dysregulated B- and T- cell functions, which lead to platelet destruction. A well-recognized mechanism of ITP pathogenesis involves anti-platelet and anti-megakaryocyte antibodies recognizing membrane glycoprotein (GP) complexes, mainly GPIb/IX and GPIIb/IIIa. In addition to the current view of phagocytosis of the opsonised platelets by splenic and hepatic macrophages via their Fc γ receptors, antibody-induced platelet desialylation and apoptosis have also been reported to contribute to ITP pathogenesis. Nevertheless, the relationship between the specific thrombocytopenic mechanisms and various types of anti-platelet antibodies has not been established. In order to ascertain such association, we used sera from 61 ITP patients and assessed the capacity of anti-platelet antibodies to induce neuraminidase 1 (NEU1) surface expression, RCA-1 lectin binding and loss of mitochondrial inner membrane potential on donors’ platelets. Sera from ITP patients with detectable antibodies caused significant platelet desialylation and apoptosis. Anti-GPIIb/IIIa antibodies appeared more capable of causing NEU1 surface translocation while anti-GPIb/IX complex antibodies resulted in a higher degree of platelet apoptosis. In ITP patients with anti-GPIIb/IIIa antibodies, both desialylation and apoptosis were dependent on FcγRIIa signaling rather than platelet activation. Finally, we confirmed in a murine model of ITP that destruction of human platelets induced by anti-GPIIb/IIIa antibodies can be prevented with the NEU1 inhibitor oseltamivir. A collaborative clinical trial is warranted to investigate the utility of oseltamivir in the treatment of ITP.     

Depression,anxiety and disease-related distress in couples affected by advanced lung cancer

Objectives

Lung cancer patients and their partners are prone to high levels of depression and anxiety or severe distress related to the poor prognosis of the illness. However, there remain doubts regarding the extent to which this distress exceeds levels in the general population. This study explored levels of depression and generalized anxiety for comparison with matched data of a representative sample from the general population. Additionally, covariance of distress between the two partners, together with disease-specific components and differences were investigated.

Materials and methods

In a cross-sectional survey, 54 pairs of lung cancer patients and their partners (n = 108) were assessed for depression and anxiety, cancer-related distress, unmet needs and disclosure in communication. Comparisons between distress levels of participating couples and matched community-comparisons (n = 162) were conducted. Additionally, multilevel analysis for estimating intra-dyadic associations of anxiety and depression was computed. Components of distress, needs and aspects of communication were explored via item mean values.

Results

Lung cancer patients as well as their partners exhibited significantly higher levels of depression and anxiety when compared to community-based comparison subjects (patients: mean difference of 1.01 for depression with a relative risk (RR) of 4.5 and 0.84 for anxiety with RR = 6.1; partners: 1.17 for depression with RR = 4.6 and 1.59 for anxiety with RR = 7.6). Partial intraclass correlations between patients and partners were weak (PIC = .29 for depression; PIC = .21 for anxiety). Fear of progression emerged as main component of distress for both patients and partners, although differing stressors were described.

Conclusion

Lung cancer-affected couples exhibit levels of depression and anxiety far exceeding those of the general community. In clinical practice, patients and partners should be assessed separately for distress against the background of weak intra-dyadic associations. In cases of significant depression or anxiety, referral for psychosocial treatment is indicated and has been shown to improve quality of life.