Health-related quality of life in patients with myalgic encephalomyelitis/chronic fatigue syndrome: an Australian cross-sectional study.

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious and debilitating disorder associated with significant disruptions in daily life including. This study aimed to examine the impact of sociodemographic and patient symptom characteristics on health-related quality of life (HRQoL) of Australians with ME/CFS. METHODS: Self-reported data collected from 480 individuals diagnosed with ME/CFS were obtained between August 2014 and August 2018. This cross-sectional survey analysed sociodemographic, symptom characteristics and HRQoL according to the 36-Item Health Survey (SF-36). Multivariate linear regression models were used to determine ME/CFS symptoms associated with eight domains of HRQoL. RESULTS: Reported HRQoL was significantly impaired in ME/CFS patients across all domains compared with the general population. Scores were the lowest for physical role (4.11 ± 15.07) and energy/fatigue (13.54 ± 13.94). Associations with females, higher body mass index (BMI), employment status, cognitive difficulties, sensory disturbances and cardiovascular symptoms were observed in the physical functioning domain. Impaired pain domain scores were associated with high BMI, annual visits to their general practitioner, flu-like symptoms and fluctuations in body temperature. Reduced well-being scores were associated with smoking status, psychiatric comorbidity, cognitive difficulties, sleep disturbances and gastrointestinal difficulties. CONCLUSION: This study provides evidence that ME/CFS has a profound and negative impact on HRQoL in an Australian cohort.

Roles for endothelial zinc homeostasis in vascular physiology and coronary artery disease.

The discovery of the roles of nitric oxide (NO) in cardiovascular signaling has led to a revolution in the understanding of cardiovascular disease. A new perspective to this story involving zinc (Zn) is emerging. Zn and its associated Zn transporter proteins are important for the integrity and functions of both the large conduit vessels and the microvascular resistance vessels. The Zn and NO pathways are tightly coordinated. Zn ions are required for the dimerization of endothelial nitric oxide synthase and subsequent generation of NO while generation of NO leads to a rapid mobilization of endothelial Zn stores. Labile Zn may mediate important downstream actions of NO including vascular cytoprotection and vasodilation. Several vascular disease risk factors (including aging, smoking and diabetes) interfere with Zn homeostatic mechanisms and both hypozincaemia and Zn transporter protein abnormalities are linked to atherosclerosis and microvascular disease. Some vegetarian diets and long-term use of certain anti-hypertensives may also impact on Zn status. The available evidence supports the existence of a Zn regulatory pathway in the vascular wall that is coupled to the generation and actions of NO and which is compromised in Zn deficiency with consequent implications for the pathogenesis and therapy of vascular disease.

Axitinib versus sorafenib in advanced renal cell carcinoma: subanalyses by prior therapy from a randomised phase III trial.

BACKGROUND: In the AXIS trial, axitinib prolonged progression-free survival (PFS) vs sorafenib in patients with advanced renal cell carcinoma (RCC) previously treated with sunitinib or cytokines. METHODS: In post hoc analyses, patients were grouped by objective response to prior therapy (yes vs no), prior therapy duration (< vs ⩾median), and tumour burden (baseline sum of the longest diameter < vs ⩾median). PFS and overall survival (OS), and safety by type and duration of prior therapy were evaluated. RESULTS: Response to prior therapy did not influence outcome with second-line axitinib or sorafenib. PFS was significantly longer in axitinib-treated patients who received longer prior cytokine treatment and sorafenib-treated patients with smaller tumour burden following sunitinib. Overall survival with the second-line therapy was longer in patients who received longer duration of prior therapy, although not significant in the sunitinib-to-axitinib sequence subgroup; OS was also longer in patients with smaller tumour burden, but not significant in the cytokine-to-axitinib sequence subgroup. Safety profiles differed modestly by type and duration of prior therapy. CONCLUSIONS: AXIS data suggest that longer duration of the first-line therapy generally yields better outcome with the second-line therapy and that lack of response to first-line therapy does not preclude positive clinical outcomes with a second-line vascular endothelial growth factor-targeted agent in patients with advanced RCC.

Radiation sterilization of anthracycline antibiotics in solid state.

The impact of ionizing radiation generated by a beam of electrons of 25-400 kGy on the stability of such analogs of anthracycline antibiotics as daunorubicin (DAU), doxorubicin (DOX), and epidoxorubicin (EPI) was studied. Based on EPR results, it was established that unstable free radicals decay exponentially with the half-time of 4 days in DAU and DOX and 7 days in EPI after irradiation. Radiation-induced structural changes were analyzed with the use of spectrophotometric methods (UV-Vis and IR) and electron microscope imaging (SEM). A chromatographic method (HPLC-DAD) was applied to assess changes in the contents of the analogs in the presence of their impurities. The study showed that the structures of the analogs did not demonstrate any significant alterations at the end of the period necessary for the elimination of unstable free radicals. The separation of main substances and related substances (impurities and potential degradation products) allowed determining that no statistically significant changes in the content of particular active substances occurred and that their conversion due to the presence of free radicals resulting from exposure to an irradiation of 25 kGy (prescribed to ensure sterility) was not observed.

Inflammasome gene expression alterations in Staphylococcus aureus biofilm-associated chronic rhinosinusitis.

BACKGROUND: The role of inflammasomes in chronic inflammation has been the subject of intense research in recent years. Chronic rhinosinusitis (CRS), a persistent inflammatory disease, continues to be investigated hoping that a clearer pathophysiologic description will guide discovery of future treatment modalities. This study investigates the role of inflammasome complexes in CRS patients with Staphylococcus aureus biofilm infection, a key culprit associated with disease severity and recalcitrance. METHODOLOGY: Sinonasal tissue samples were collected from CRS patients with (P+) and without (P-) polyps and controls. S. aureus biofilm status was obtained using fluorescence in situ hybridization and classified as biofilm positive (B+) or negative (B-). RNA was analysed using a Human Inflammasome PCR array, profiling the expression of 84 genes involved in inflammasome function. RESULTS: Sixteen samples were obtained: 5 B+P+, 5 B-P- and 6 controls. Comparing B+P+ vs. controls showed the greatest number of differentially expressed genes. In particular, Absent in Melanoma 2 (AIM2) was consistently and significantly up-regulated in the B+P+ vs. B-P- and controls. In contrast, when comparing the B-P- vs. controls, no genes showed significant changes. CONCLUSION: Our results indicate the involvement of inflammasome complexes and their signalling pathways in CRS patients with polyps and S. aureus biofilms. In particular, AIM2, activated by intracellular double-stranded DNA, is up-regulated in this group, implying that S. aureus may play a role in intracellular triggering of the inflammasome response. Studies with further patient stratification and assessing corresponding protein expression are needed to further characterize the role of inflammasomes in CRS.

Diabetes-linked zinc transporter ZnT8 is a homodimeric protein expressed by distinct rodent endocrine cell types in the pancreas and other glands.

BACKGROUND AND AIMS: Zinc is abundant in pancreas, being required by endocrine islet cells for hormone secretion and by exocrine acinar cells as pancreatic juice component. ZnT8 is a member of the SLC30A family of zinc transporters whose overexpression in cultured pancreatic beta cells leads to increased insulin secretion in response to glucose, suggesting a possible role in regulating glycemia. ZnT8 was therefore proposed as a therapeutic target for diabetes, and recent genome-wide association studies identified polymorphisms in the ZNT8 gene conferring increased type 2 diabetes risk. METHODS AND RESULTS: As limited information was available on the biochemical properties of ZnT8 and on its endogenous expression, we have raised a specific polyclonal antibody and immunostained protein extracts, cell lines and tissue sections. We show that ZnT8 forms a very stable dimer that requires biological membranes to properly assemble. We demonstrate localization of murine ZnT8 to the secretory granules in pancreatic beta and alpha islet cells. Moreover, we show that ZnT8 is also expressed in other secretory cell types, namely the cubical epithelium that lines thyroid follicles and the cortex of the adrenal gland, suggesting a more widespread role in endocrine secretion. CONCLUSION: We provide novel insights into the features of the ZnT8 transporter, of special relevance in light of its proposed role as therapeutical target for diabetes treatment.

Reflex influence of carotid baroreceptor inactivation on respiratory resistance in humans.

Our previous study demonstrated that selective carotid baroreceptors activation decreases airway resistance. The aim of the present study was to evaluate the effect of carotid baroreceptor inactivation on the reflex change of respiratory resistance. Twenty healthy men aged between 20 and 25 were included in the study. Selective inactivation of carotid baroreceptors was induced by generating a positive pressure of 40 mmHg for 5 s in two capsules placed bilaterally on the neck over the bifurcation of the carotid arteries. The oscillatory method (Siregnost FD5, Siemens) was used to measure continuously respiratory resistance. Inactivation of carotid baroreceptors produced a short increase in respiratory resistance by 0.39 +/- 0.01(SE) mbar/l/s, i.e., 21.7% above the resting level. We conclude that in humans, carotid baroreceptors might have a background contribution to bronchodilator tone. This observation seems to be important for clinical situations of impairment of baroreflex function.

Impairment of the baroreflex control of human respiratory resistance with age.

BACKGROUND: The mechanism responsible for the central baroreflex resetting with age are an area of limited knowledge. We previously demonstrated that in subjects aged above 50 the airway resistance did not change in response to baroreceptor activation, whereas in younger volunteers the airway resistance significantly decreased. OBJECTIVE: The aim of the present study was to evaluate the effect of carotid baroreceptor inactivation on the reflex change of respiratory resistance, in the course of aging. MATERIAL AND METHODS: 80 healthy men, divided in four groups: aged 20-30 (Group I), 31-40 (Group II), 41-50 (Group III), and 51-60 (Group IV) were included in the study. The selective inactivation of carotid baroreceptors was induced by generating a positive pressure of 40 mmHg for 5 s in two capsules placed bilaterally on the neck over the bifurcation of the carotid arteries. The oscillatory method (Siregnost FD5, Siemens) was used to measure continuously respiratory resistance. RESULTS: Inactivation of carotid baroreceptors produced a short increase in respiratory resistance by 0.38 +/- 0.01SE mbar/l/s, i.e., 21.7% above the resting level in Group I and by 0.25 +/- 0.01 mbar/l/s in Group II. In the two older groups (III and IV) respiratory resistance did not change in response to baroreceptors inactivation. CONCLUSIONS: In humans aged above 40, carotid baroreceptors do not contribute to bronchodilator tone, which causes imbalance between the activities of upper airway and chest wall inspiratory muscles leading to a collapsing effect on the upper airway.

Cardiovascular regulation and body temperature: evidence from a nap vs. sleep deprivation randomized controlled trial.

In this study we set out to understand is sleep fragmentation affects the cardiovascular regulation and circadian variability of core body temperature more or less than sleep deprivation. 50 healthy men (age 29.0+/-3.1 years; BMI 24.3+/-2.1 kg/m(2)) participated in a 3-day study that included one adaptative night and one experimental night involving randomization to: sleep deprivation (SD) and sleep fragmentation (SF). The evaluation included hemodynamic parameters, measures of the spectral analysis of heart rate and blood pressure variability, and the sensitivity of arterial baroreflex function. Core body temperature (CBT) was measured with a telemetric system. SF affects heart rate (61.9+/-5.6 vs. 56.2+/-7.6, p<0.01) and stroke index (52.7+/-11.1 vs. 59.8+/-12.2, p<0.05) with significant changes in the activity of the ANS (LF-sBP: 6.0+/-5.3 vs. 3.4+/-3.7, p<0.05; HF-sBP: 1.8+/-1.8 vs. 1.0+/-0.7, p<0.05; LF-dBP: 5.9+/-4.7 vs. 3.5+/-3.2, p<0.05) more than SD. Post hoc analysis revealed that after SD mean value of CBT from 21:30 to 06:30 was significantly higher compared to normal night's sleep and SF. In healthy men SF affects the hemodynamic and autonomic changes more than SD. Sympathetic overactivity is the proposed underlying mechanism.

Cardiovascular regulation and body temperature: evidence from a nap vs. sleep deprivation randomized controlled trial.

In this study we set out to understand is sleep fragmentation affects the cardiovascular regulation and circadian variability of core body temperature more or less than sleep deprivation. 50 healthy men (age 29.0+/-3.1 years; BMI 24.3+/-2.1 kg/m(2)) participated in a 3-day study that included one adaptative night and one experimental night involving randomization to: sleep deprivation (SD) and sleep fragmentation (SF). The evaluation included hemodynamic parameters, measures of the spectral analysis of heart rate and blood pressure variability, and the sensitivity of arterial baroreflex function. Core body temperature (CBT) was measured with a telemetric system. SF affects heart rate (61.9+/-5.6 vs 56.2+/-7.6, p<0.01) and stroke index (52.7+/-11.1 vs. 59.8+/-12.2, p<0.05) with significant changes in the activity of the ANS (LF-sBP: 6.0+/-5.3 vs. 3.4+/-3.7, p<0.05; HF-sBP: 1.8+/-1.8 vs 1.0+/-0.7, p<0.05; LF-dBP: 5.9+/-4.7 vs. 3.5+/-3.2, p<0.05) more than SD. Post-hoc analysis revealed that after SD mean value of CBT from 21:30 to 06:30 was significantly higher compared to normal night's sleep and SF. In healthy men SF affects the hemodynamic and autonomic changes more than SD. Sympathetic overactivity is the proposed underlying mechanism.

Zinc and its specific transporters as potential targets in airway disease.

The dietary group IIb metal zinc (Zn) plays essential housekeeping roles in cellular metabolism and gene expression. It regulates a number of cellular processes including mitosis, apoptosis, secretion and signal transduction as well as critical events in physiological processes as diverse as insulin release, T cell cytokine production, wound healing, vision and neurotransmission. Critical to these processes are the mechanisms that regulate Zn homeostasis in cells and tissues. The proteins that control Zn uptake and compartmentalization are rapidly being identified and characterized. Recently, the first images of sub-cellular pools of Zn in airway epithelium have been obtained. This review discusses what we currently know about Zn in the airways, both in the normal and inflamed states, and then considers how we might target Zn metabolism by developing strategies to monitor and manipulate airway Zn levels in airway disease.

Induction of caspase-3 protease activity and apoptosis by butyrate and trichostatin A (inhibitors of histone deacetylase): dependence on protein synthesis and synergy with a mitochondrial/cytochrome c-dependent pathway.

The induction of apoptosis of tumor cells by the colonic fermentation product butyrate is thought to be an important mechanism in protection against colorectal cancer. Because a major action of butyrate is to inhibit histone deacetylase (leading to chromatin relaxation and altered gene expression), butyrate may induce apoptosis by derepression of specific cell death genes. Here we show that butyrate and trichostatin A (a more selective inhibitor of histone deacetylase) induce the same program of apoptosis in Jurkat lymphoid and LIM 1215 colorectal cancer cell lines that is strictly dependent on new protein synthesis (within 10 h) and that leads to the conversion of the proenzyme form of caspase-3 to the catalytically active effector protease (within 16 h) and apoptotic death (within 24 h). Cells primed with a low concentration of butyrate that itself did not induce activation of caspase-3 or apoptosis were, nevertheless, rendered highly susceptible to induction of apoptosis by staurosporine (an agent that has recently been shown to act by causing mitochondrial release of cytochrome c). Synergy between butyrate and staurosporine was due to the presence of a factor in the cytosol of butyrate-primed cells which enhanced over 7-fold the activation of caspase-3 induced by the addition of cytochrome c and dATP to isolated cytosol. We propose that changes at the level of chromatin structure, induced by a physiological substance butyrate, lead to the expression of a protein that facilitates the pathway by which mitochondria activate caspase-3 and trigger apoptotic death of lymphoid and colorectal cancer cells.

Agglutination of mouse erythrocytes by binding of non-choline phospholipids to a 70 000-Dalton protein.

The structure of some phospholipids that cause agglutination of mouse erythrocytes has been studied. Haemagglutination is a property of non-choline-containing phospholipids; the phosphate group is essential and unsaturated fatty acids optimal. A protein of Mr 70 000 was isolated from mouse erythrocyte membranes which completely inhibited phospholipid-mediated erythrocyte agglutination. It is proposed that this protein is the phospholipid binding site on mouse erythrocytes and the ligand for the human B-lymphocyte receptor for mouse erythrocytes. Preliminary investigations suggest that a similar inhibitor of phospholipid-mediated agglutination is found in serum. Agglutination of mouse erythrocytes by phospholipid and specific inhibition by the 70 kDa membrane protein constitute a simple system for studying the interaction of phospholipid with protein.

A subclass of albumin recognized by inhibition of phosphatidylethanolamine-mediated agglutination of mouse erythrocytes.

Agglutination of mouse erythrocytes by non-choline phospholipids is inhibited by a factor in mammalian sera. The inhibitor cochromatographed with albumin on dye-agarose conjugates, was retained by an anti-albumin affinity column, was neutralized by anti-albumin antibody and found in a serum fraction in which only albumin could be detected. A variety of commercial preparations of albumin (fraction V, crystalline) did not inhibit. However, they acquired potent inhibitory activity when treated with low molecular weight thiols. The inhibitory activity of serum was increased 8-fold by treatment with dithiothreitol. Other proteins were not activated in this way. Inhibitory activity increased with average free sulphydryl content of treated albumin, up to six thiol groups per molecule. Alkylation of these sulphydryl groups did not diminish inhibitory activity. Thiols also induced polymerization of albumin. Inhibitory albumin in serum was largely monomeric. We propose that the inhibitor is a type of serum albumin which is lost or inactivated during preparation of commercial albumin, and which shares a structural feature, necessary for inhibition, with thiol-reduced albumin and the ligand on mouse erythrocytes.

Interaction between protein kinase C and regulatory ligand is enhanced by a chelatable pool of cellular zinc.

At micromolar concentrations, zinc (Zn) and cadmium, but not other metals, greatly augmented binding of [3H]phorbol dibutyrate ([3H]PDBu) to protein kinase C (PKC) in cell homogenates and intact cells (in the presence of ionophore). Increased binding persisted for several hours. The heavy-metal chelating agent 1,10-phenanthroline completely reversed the increased [3H]PDBu binding in cells pretreated with 65Zn and ionophore and this was associated with a decline of about 20% in cell-associated 65Zn, suggesting that a relatively small pool of intracellular Zn acts on PKC. This may be a membrane-associated pool, since 65Zn readily bound to isolated erythrocyte inside-out membranes. Phenanthroline also partially inhibited binding of [3H]PDBu to PKC in untreated cells and extracts in a Zn-reversible manner. Therefore, cellular Zn appears to regulate the interaction of ligand with PKC. PKC bound to a Zn affinity column and was eluted by metal-chelator, confirming that Zn interacts directly with PKC.

Flux of intracellular labile zinc during apoptosis (gene-directed cell death) revealed by a specific chemical probe, Zinquin.

BACKGROUND: The transition metal Zn(II) is thought to regulate cell and tissue growth by enhancing mitosis (cell proliferation) and suppressing the counterbalancing process of apoptosis (gene-directed cell death). To investigate the role of Zn(II) further, we have used a UV-excitable Zn(II)-specific fluorophore, Zinquin. The ester group of Zinquin is hydrolyzed by living cells, ensuring its intracellular retention; this allows the visualization and measurement of free or loosely-bound (labile) intracellular Zn(II) by fluorescence video image analysis or fluorimetric spectroscopy. RESULTS: Here we show that in cells undergoing early events of apoptosis, induced spontaneously or by diverse agents, there is a substantial increase in their Zinquin-detectable Zn(II). This increase occurred in the absence of exogenous Zn(II) and before changes in membrane permeability, consistent with a release of Zn(II) from intracellular stores or metalloproteins rather than enhanced uptake from the medium. We propose that there is a major redistribution of Zn(II) during the induction of apoptosis, which may influence or precipitate some of the later biochemical and morphological changes. CONCLUSIONS: The phenomenon of Zn(II) mobilization, revealed by Zinquin, presents a new element in the process of apoptosis for investigation and may permit rapid and sensitive identification of apoptotic cells, particularly in those tissues where their frequency is low.

Zinc in health and chronic disease.

Zinc is a trace element essential for the optimal function of a variety of biochemical and physiological processes. Its role in healthy aging is particularly important as it prevents neo plastic cell growth, is involved in mitotic cell division, DNA and RNA repair. Although zinc is widely available in food, the daily intake in many persons may be suboptimal. Other causes of low zinc concentrations may be due to small bowel conditions that cause mucosal damage and thus decrease absorption. Chronic diseases associated with alterations in zinc status are bronchial asthma, rheumatoid arthritis and Alzheimer disease. At present it is uncertain if therapy with zinc would assist in the management of these chronic diseases. In view of the important cellular functions of zinc in the human body, a diet with an adequate zinc content is beneficial in promoting healthy aging and maintaining good health.

Zinc increases phorbol ester receptors in intact B-cells, neutrophil polymorphs and platelets.

In the presence of pyrithione, which was used as a Zn2+ ionophore, Zn2+ (10-100 microM) increased phorbol ester binding by intact B-CLL cells in a dose-dependent fashion. Zn pyrithione increased 2-fold the number of phorbol ester receptors in B-cells (0.74 to 1.4 pmol/10(6) cells), neutrophil polymorphs (0.2 to 0.51 pmol/10(6) cells) and platelets (91 to 209 pmol/10(10) cells). Fractionation of cells after treatment with Zn pyrithione showed that increased binding of PDBu occurred in the particulate fraction of cells and this was accompanied by loss of phorbol ester receptors from the cytosol. These data are compatible with a role for Zn in the subcellular distribution and activation of protein kinase C.

Synergy between zinc and phorbol ester in translocation of protein kinase C to cytoskeleton.

Protein kinase C was measured in the cytoskeletal fraction of lymphocytes, platelets and HL60 cells, by specific binding of [3H]phorbol dibutyrate and by immunoblotting with antibody to a consensus sequence in the regulatory domain of alpha-, beta- and gamma-isozymes of protein kinase C. Treatment of cells for 40 min with a combination of zinc (2-50 microM), zinc ionophore pyrithione and unlabelled phorbol dibutyrate (200 nM) caused up to a ten-fold increase in cytoskeletal protein kinase C and a corresponding decrease in other cellular compartments. Omission of any of the reagents resulted in much less or no translocation. These effects were inhibited by 1,10-phenanthroline, which chelates zinc, and were not seen with calcium. Increase in cytoskeletal protein kinase C persisted for several hours and appeared to involve attachment of the enzyme to actin microfilaments. We propose that zinc, like calcium, regulates the distribution of PKC in cells. However, unlike calcium which controls the binding of PKC to the lipid component on cell membranes, zinc controls the distribution of PKC to membrane cytoskeleton, possibly actin.

Calcium ionophore A23187 enhances human neutrophil superoxide release, stimulated by phorbol dibutyrate, by converting phorbol ester receptors from a low- to high-affinity state.

The calcium ionophore A23187 acted synergistically with phorbol dibutyrate (PDBu) to stimulate human neutrophil superoxide production. A23187 shortened the lag period and markedly increased the initial rate of neutrophil superoxide production induced by suboptimal concentrations of PDBu. 1 microM A23187 reduced the EC50 value for superoxide release from 56 to 8 nM PDBu. This effect of A23187 was correlated with enhanced binding of [3H]PDBu to its receptor and a reduction in the dissociation constant (Kd) from 27 to 10 nM, without altering the apparent total number of phorbol dibutyrate receptors. These actions of A23187 were abolished in the presence of EGTA or TMB-8, confirming a dependence on Ca2+.