Simulation of carbon cycling, including dissolved organic carbon transport, in forest soil locally enriched with 14C

The DyDOC model was used to simulate the soil carbon cycle of a deciduous forest at the Oak Ridge Reservation (Tennessee, USA). The model application relied on extensive data from the Enriched Background Isotope Study (EBIS), which exploited a short-term local atmospheric enrichment of radiocarbon to establish a large-scale manipulation experiment with different inputs of 14C from both above-ground and below-ground litter. The model was first fitted to hydrological data, then observed pools and fluxes of carbon and 14C data were used to fit parameters describing metabolic transformations of soil organic matter (SOM) components and the transport and sorption of dissolved organic matter (DOM). This produced a detailed quantitative description of soil C cycling in the three horizons (O, A, B) of the soil profile. According to the parameterised model, SOM turnover within the thin O-horizon rapidly produces DOM (46 gC m-2 a-1), which is predominantly hydrophobic. This DOM is nearly all adsorbed in the A- and B-horizons, and while most is mineralised relatively quickly, 11 gC m-2 a-1 undergoes a “maturing” reaction, producing mineral-associated stable SOM pools with mean residence times of 100-200 years. Only a small flux (~ 1 gC m-2 a-1) of hydrophilic DOM leaves the B-horizon. The SOM not associated with mineral matter is assumed to be derived from root litter, and turns over quite quickly (mean residence time 20-30 years). Although DyDOC was successfully fitted to C pools, annual fluxes and 14C data, it accounted less well for short-term variations in DOC concentrations

Carvedilol Protects against Doxorubicin-Induced Mitochondrial Cardiomyopathy

Several cytopathic mechanisms have been suggested to mediate the dose-limiting cumulative and irreversible cardiomyopathy caused by doxorubicin. Recent evidence indicates that oxidative stress and mitochondrial dysfunction are key factors in the pathogenic process. The objective of this investigation was to test the hypothesis that carvedilol, a nonselective [beta]-adrenergic receptor antagonist with potent antioxidant properties, protects against the cardiac and hepatic mitochondrial bioenergetic dysfunction associated with subchronic doxorubicin toxicity. Heart and liver mitochondria were isolated from rats treated for 7 weeks with doxorubicin (2 mg/kg sc/week), carvedilol (1 mg/kg ip/week), or the combination of the two drugs. Heart mitochondria isolated from doxorubicin-treated rats exhibited depressed rates for state 3 respiration (336 ± 26 versus 425 ± 53 natom O/min/mg protein) and a lower respiratory control ratio (RCR) (4.3 ± 0.6 versus 5.8 ± 0.4) compared with cardiac mitochondria isolated from saline-treated rats. Mitochondrial calcium-loading capacity and the activity of NADH-dehydrogenase were also suppressed in cardiac mitochondria from doxorubicin-treated rats. Doxorubicin treatment also caused a decrease in RCR for liver mitochondria (3.9 ± 0.9 versus 5.6 ± 0.7 for control rats) and inhibition of hepatic cytochrome oxidase activity. Coadministration of carvedilol decreased the extent of cellular vacuolization in cardiac myocytes and prevented the inhibitory effect of doxorubicin on mitochondrial respiration in both heart and liver. Carvedilol also prevented the decrease in mitochondrial Ca2+ loading capacity and the inhibition of the respiratory complexes of heart mitochondria caused by doxorubicin. Carvedilol by itself did not affect any of the parameters measured for heart or liver mitochondria. It is concluded that this protection by carvedilol against both the structural and functional cardiac tissue damage may afford significant clinical advantage in minimizing the dose-limiting mitochondrial dysfunction and cardiomyopathy that accompanies long-term doxorubicin therapy in cancer patients.http://www.sciencedirect.com/science/article/B6WXH-47G34FR-7/1/591ea3d1072dcf2971b640191c05679

Delayed ethylene glycol poisoning presenting with abdominal pain and multiple cranial and peripheral neuropathies: a case report

<p>Abstract</p> <p>Introduction</p> <p>Ethylene glycol poisoning may pose diagnostic difficulties if the history of ingestion is not volunteered, or if the presentation is delayed. This is because the biochemical features of high anion-gap metabolic acidosis and an osmolar gap resolve within 24 to 72 hours as the ethylene glycol is metabolized to toxic metabolites. This case illustrates the less well-known clinical features of delayed ethylene glycol poisoning, including multiple cranial and peripheral neuropathies, and the clinical findings which may point towards this diagnosis in the absence of a history of ingestion.</p> <p>Case presentation</p> <p>A 53-year-old Afro-Caribbean man presented with vomiting, abdominal pain and oliguria, and was found to have acute renal failure requiring emergency hemofiltration, and raised inflammatory markers. Computed tomography imaging of the abdomen revealed the appearance of bilateral pyelonephritis, however he failed to improve with broad-spectrum antibiotics, and subsequently developed multiple cranial neuropathies and increasing obtundation, necessitating intubation and ventilation. Computed tomography of the brain showed no focal lesions, and a lumbar puncture revealed a raised cerebrospinal fluid opening pressure and cyto-albuminological dissociation. Nerve conduction studies revealed a sensorimotor radiculoneuropathy mimicking a Guillain-Barre type lesion with an atypical distribution. It was only about two weeks after presentation that the history of ethylene glycol ingestion one week before presentation was confirmed. He had a slow recovery on the intensive care unit, requiring renal replacement therapy for eight weeks, and complicated by acute respiratory distress syndrome, neuropathic pain and a slow neurological recovery requiring prolonged rehabilitation.</p> <p>Conclusions</p> <p>Although neuropathy as a result of ethylene glycol poisoning has been described in a few case reports, all of these were in the context of a known history of ingestion. As the diagnosis may well be obscured if the history of ingestion is not elucidated, it is important to be aware of this possibility especially if presentation is delayed.</p

Back pain reporting in young girls appears to be puberty-related

BACKGROUND: There is a large increase in back pain reporting in the early teens. In no previous study has the prevalence of low back pain been investigated in relation to the onset of puberty. The objective of this study was to establish whether the onset of puberty is associated with back pain reporting in young girls. METHODS: A subsample of 254 girls aged 8–10 years and 165 girls aged 14–16 years from a cross-sectional survey of 481 children aged 8–10 years and 325 adolescents aged 14–16 years of both sexes. Main outcome measures were back pain defined as low back pain, mid back pain, and/or neck pain in the past month. Other variables of interest were Puberty (five different stages), age, body mass index, and smoking. Independent information on onset of puberty was obtained through a physical examination and on back pain through an individual structured interview. The association was studied between onset of puberty and the outcome variable (the one month period prevalence of back pain), controlling for overweight, and smoking. Odds ratios with 95% confidence intervals were used to describe bivariate associations, logistic regression with robust standard errors was used for multivariate analyses. RESULTS: There is a highly significant trend for increased back pain reporting with increasing level of puberty until maturity is reached. The biggest leap appears between the second level (beginning of puberty) and the third level (mid puberty) and the findings remain after controlling for the covariates. These results emanate from the low back, whereas pain in the mid back and neck do not seem to be linked with pubertal stage. CONCLUSION: In girls, the reporting of low back pain increases in frequency during puberty until maturity, regardless of age. Why some girls are susceptible to back pain in the early stage of puberty is unknown

Calcitonin gene-related peptide-1 (CGRP-1) is a potent regulator of glycogen metabolism in rat skeletal muscle

AbstractWe investigated the effects of CGRP on glucose metabolism in intact rat skeletal muscle preparations that are largely composed of either type I (soleus) or II fibres (e.g. extensor digitorum longus (EDL) or epitrochlearis muscles). CGRP-1 inhibited insulin-stimulated glycogen synthesis in both soleus and EDL muscle preparations. Rat CGRP-1 was a potent stimulator of glycogenolysis only in muscles composed of type II fibres, which depend on high rates of glycogenolysis to produce high power outputs. These results may provide the basis for understanding how CGRP regulate glycogenolysis in type II fibres in vivo

Equating accelerometer estimates among youth : the Rosetta Stone 2

Different accelerometer cutpoints used by different researchers often yields vastly different estimates of moderate-to-vigorous intensity physical activity (MVPA). This is recognized as cutpoint non-equivalence (CNE), which reduces the ability to accurately compare youth MVPA across studies. The objective of this research is to develop a cutpoint conversion system that standardizes minutes of MVPA for six different sets of published cutpoint

Comparative analysis of distinct phenotypes in gambling disorder based on gambling preferences

Background: Studies examining gambling preferences have identified the importance of the type of gambling practiced on distinct individual profiles. The objectives were to compare clinical, psychopathological and personality variables between two different groups of individuals with a gambling disorder (strategic and non-strategic gamblers) and to evaluate the statistical prediction capacity of these preferences with respect to the severity of the disorder. Method: A total sample of 2010 treatment-seeking patients with a gambling disorder participated in this stand-alone study. All were recruited from a single Pathological Gambling Unit in Spain (1709 strategic and 301 non-strategic gamblers). The design of the study was cross-sectional and data were collected at the start of treatment. Data was analysed using logistic regression for binary outcomes and analysis of variance (ANOVA) for quantitative responses. Results: There were significant differences in several socio-demographic and clinical variables, as well as in personality traits (novelty seeking and cooperativeness). Multiple regression analysis showed harm avoidance and self-directedness were the main predictors of gambling severity and psychopathology, while age at assessment and age of onset of gambling behaviour were predictive of gambling severity. Strategic gambling (as opposed to non-strategic) was significantly associated with clinical outcomes, but the effect size of the relationships was small. Conclusions: It is possible to identify distinct phenotypes depending on the preference of gambling. While these phenotypes differ in relation to the severity of the gambling disorder, psychopathology and personality traits, they can be useful from a clinical and therapeutic perspective in enabling risk factors to be identified and prevention programs targeting specific individual profiles to be developed

Transhiatal vs extended transthoracic resection in oesophageal carcinoma: patients' utilities and treatment preferences

To assess patients' utilities for health state outcomes after transhiatal or transthoracic oesophagectomy for oesophageal cancer and to investigate the patients' treatment preferences for either procedure. The study group consisted of 48 patients who had undergone either transhiatal or transthoracic oesophagectomy. In an interview they were presented with eight possible health states following oesophagectomy. Visual Analogue Scale and standard gamble techniques were used to measure utilities. Treatment preference for either transhiatal or transthoracic oesophagectomy was assessed. Highest scores were found for the patients' own current health state (Visual Analogue Scale: 0.77; standard gamble: 0.97). Lowest scores were elicited for the health state ‘irresectable tumour’ (Visual Analogue Scale: 0.13; standard gamble: 0.34). The Visual Analogue Scale method produced lower estimates (P<0.001) than the standard gamble method for all health states. Most patient characteristics and clinical factors did not correlate with the utilities. Ninety-five per cent of patients who underwent a transthoracic procedure and 52% of patients who underwent a transhiatal resection would prefer the transthoracic treatment. No significant associations between any patient characteristics or clinical characteristics and treatment preference were found. Utilities after transhiatal or transthoracic oesophagectomy were robust because they generally did not vary by patient or clinical characteristics. Overall, most patients preferred the transthoracic procedure

Length versus radius relationship for ZnO nanowires grown via vapour phase transport

We model the growth of ZnO nanowires via vapour phase transport and examine the relationship predicted between the nanowire length and radius. The model predicts that the lengths of the nanowires increase with decreasing nanowire radii. This prediction is in very good agreement with experimental data from a variety of nanowire samples, including samples showing a broad range of nanowire radii and samples grown using a lithographic technique to constrain the nanowire radius. The close agreement of the model and the experimental data strongly support supporting the inclusion of a surface diffusion term in the model for the incorporation of species into a growing nanowire