Changes in bone structure and metabolism during simulated weightlessness: Endocrine and dietary factors

The role of vitamin D, PTH and corticosterone in the skeletal alterations induced by simulated weightlessness was examined. The first objective was to determine if changes in the serum concentrations of Ca, P sub i, osteocalcin, 25-OH-D, 24,25(OH)2D or 1,25(OH)2D also occur following acute skeletal unloading. Animals were either suspended or pair fed for 2, 5, 7, 10, 12 and 15 days and the serum concentrations of Ca, P sub i, osteocalcin and the vitamin D metabolites measured. Bone histology was examined at day 5 after suspension. Acute skeletal unloading produced a transient hypercalcemia, a significant fall in serum osteocalcin and serum 1,25(OH)2D, a slight rise in serum 24,25(OH)2D, but did not affect the serum concentrations of P sub i or 25-OH-D. At the nadir in serum 1,25(OH)2D serum osteocalcin was reduced by 22%, osteoblast surface by 32% and longitudinal bone growth by 21%

Early life history dynamics of the fish community in the Atchafalaya River Basin

Seasonal overbank flooding in systems like the Atchafalaya River Basin (ARB) provides the opportunity for fishes in the mainstem to access off-channel areas on the floodplain. Typically, newly inundated floodplain habitats allow adult fishes to add biomass, avoid predation, and potentially, to reproduce. However, in systems like the ARB, the timing, duration, and magnitude of flooding infrequently coincides with known reproductive periods of many fishes assumed to be floodplain-dependent. To quantify the level of floodplain-exploitative fish reproduction in the ARB, I collected larval and juvenile fish with a variety of sampling gear that allowed estimates in both ultra-shallow (\u3c 2-m) and continuously-inundated habitats (headwater lakes, canals, and bayous). A suite of water quality parameters, river stage, flow, and hours of daylight were used to gauge the influence of environmental phenomena on age-0 abundance during both inundation and drawdown. The results of the 19-month study suggest that many taxa do not rely on the floodplain to ensure high survivorship. Interestingly, the reproductive ecologies of many ARB fishes appeared to be largely independent of widespread connectivity. Although an increasing hydrograph appeared to enhance reproductive output, the interannual timing and intensity of spawning showed limited variability. Larval densities were also contrasted with the microcrustacean zooplankton (copepods and cladocerans) population to assess if a potential food limitation existed in the weeks and months following hatching. During the study, increased zooplankter abundance was typically preceded by elevated river-floodplain connectivity. Conversely, as floodwaters receded during the summer, zooplankton abundance declined to lowest levels observed during the study. Overall, there was limited synchronous overlap between the hatchlings of most fish taxa and their zooplankter prey. This could have potentially resulted in starvation and reduced annual recruitment. Yet, my analysis of the factors that regulate larval fish abundance in the ARB suggest that the density of zooplankton was highly significant although high numbers of larvae and zooplankton rarely coincided. Finally, I compared the intraday (morning vs. afternoon) density and mean length of larval fish at fixed sample sites. The results suggest that once-daily ichthyoplankton collections may fail to provide accurate density and length measurements for young fish populations

Using a hypothetical scenario to assess public preferences for colorectal surveillance following screening-detected, intermediate-risk adenomas: annual home-based stool test vs. triennial colonoscopy

Background To assess public preferences for colorectal cancer (CRC) surveillance tests for intermediate-risk adenomas, using a hypothetical scenario. Methods Adults aged 45–54 years without CRC were identified from three General Practices in England (two in Cumbria, one in London). A postal survey was carried out during a separate study on preferences for different first-line CRC screening modalities (non- or full-laxative computed tomographic colonography, flexible sigmoidoscopy, or colonoscopy). Individuals were allocated at random to receive a pack containing information on one first-line test, and a paragraph describing CRC surveillance recommendations for people who are diagnosed with intermediate-risk adenomas during screening. All participants received a description of two surveillance options: annual single-sample, home-based stool testing (consistent with Faecal Immunochemical Tests; FIT) or triennial colonoscopy. Invitees were asked to imagine they had been diagnosed with intermediate-risk adenomas, and then complete a questionnaire on their surveillance preferences. Results 22.1 % (686/3,100) questionnaires were returned. 491 (15.8 %) were eligible for analysis. The majority of participants stated a surveillance preference for the stool test over colonoscopy (60.8 % vs 31.0 %; no preference: 8.1 %; no surveillance: 0.2 %). Women were more likely to prefer the stool test than men (66.7 % vs. 53.6 %; p = .011). The primary reason for preferring the stool test was that it would be done more frequently. The main reason to prefer colonoscopy was its superiority at finding polyps. Conclusions A majority of participants stated a preference for a surveillance test resembling FIT over colonoscopy. Future research should test whether this translates to greater adherence in a real surveillance setting

The role of 1,25-dihydroxyvitamin D in the inhibition of bone formation induced by skeletal unloading

Skeletal unloading results in osteopenia. To examine the involvement of vitamin D in this process, the rear limbs of growing rats were unloaded and alterations in bone calcium and bone histology were related to changes in serum calcium (Ca), inorganic phosphorus (P sub i), 25-hydroxyvitamin D (25-OH-D), 24,25-dihydroxyvitamin D (24,25(OH)2D and 1,25-dihydroxyvitamin D (1,25(OH)2D. Acute skeletal unloading induced a transitory inhibition of Ca accumulation in unloaded bones. This was accompanied by a transitory rise in serum Ca, a 21% decrease in longitudinal bone growth (P 0.01), a 32% decrease in bone surface lined with osteoblasts (P .05), no change in bone surface lined with osteoclasts and a decrease in circulating (1,25(OH)2D. No significant changes in the serum concentrations of P sub i, 25-OH-D or 24,25(OH)2D were observed. After 2 weeks of unloading, bone Ca stabilized at approximately 70% of control and serum Ca and 1,25(OH)2D returned to control values. Maintenance of a constant serum 1,25(OH)2D concentration by chronic infusion of 1,25(OH)2D (Alza osmotic minipump) throughout the study period did not prevent the bone changes induced by acute unloading. These results suggest that acute skeletal unloading in the growing rat produces a transitory inhibition of bone formation which in turn produces a transitory hypercalcemia

Effect of heavy metals in recycled water used for household laundry on quality of cloth and washing machine

Recycled water for washing clothes saves significant amount of potable water and hence has a great potential for sustainable urban-water management. To date, there has been no official acceptance and very rare practice of use of recycled water for household laundry. This study investigates the effects of critical heavy metals (Pb, Mn, Fe, Cu and Zn) on cloth quality and corrosive/scaling of washing machine to evaluate the feasibility of using recycled water for household laundry. The experimental data can be used for future recycled-water-quality guidelines. Five representative cloth materials namely polyester, satin, polycotton, denim and organic cotton were selected for washing in tap water and synthetic recycled water which contained different concentrations of heavy metals. Cloth durability, surface morphology and textile colour of washed cloth samples were measured to investigate the effects of heavy metals on quality of fabric. Langelier Saturation Index (LSI) was used as the indicator for predicting corrosive/scaling effects on washing machine. The results indicated that quality of fabrics after 50 wash cycles was found to have no change by recycled water when concentration of Pb and Mn < 0.5 mg/L, Fe < 1 mg/L, Cu < 5 mg/L and Zn < 30 mg/L. Lower than the above values, the LSI indicated that recycled water would not lead to any negative impact on washing machine

FluTE, a Publicly Available Stochastic Influenza Epidemic Simulation Model

Mathematical and computer models of epidemics have contributed to our understanding of the spread of infectious disease and the measures needed to contain or mitigate them. To help prepare for future influenza seasonal epidemics or pandemics, we developed a new stochastic model of the spread of influenza across a large population. Individuals in this model have realistic social contact networks, and transmission and infections are based on the current state of knowledge of the natural history of influenza. The model has been calibrated so that outcomes are consistent with the 1957/1958 Asian A(H2N2) and 2009 pandemic A(H1N1) influenza viruses. We present examples of how this model can be used to study the dynamics of influenza epidemics in the United States and simulate how to mitigate or delay them using pharmaceutical interventions and social distancing measures. Computer simulation models play an essential role in informing public policy and evaluating pandemic preparedness plans. We have made the source code of this model publicly available to encourage its use and further development

The outcome of kidney transplants with multiple renal arteries

BACKGROUND: The use of grafts with multiple renal arteries has been considered a relative contraindication because of the increased incidence of vascular and urologic complications The aim of this study is to determine whether the kidney grafts with multiple arteries have any adverse effect upon post-transplant graft and patient survival. METHODS: We reviewed the records of 225 adult kidney transplants done consecutively at our institution. Twenty-nine patients (12.8%) had grafts with multiple renal arteries. We analyzed the incidence of post-transplant hypertension and vascular complications, mean creatinine levels, patient and graft survival. In 17 cases reconstruction was done as conjoined anastomosis between two arteries of equal size, and in 6 cases as end-to-side anastomosis of smaller arteries to larger arteries. Multiple anastomoses were performed in 6 cases. RESULTS: In one patient postoperative bleeding occurred. Mean systolic blood pressures, creatinine levels at first year and last follow-up and complication rates were all in acceptable ranges. There was no significant difference in graft and patient survival between multiple and single renal artery allografts. CONCLUSION: Although the kidney grafts with multiple renal arteries have been considered a relative contraindication because of the increased risk of complications, in our study allografts with multiple arteries were used successfully in kidney transplantation

Dried Plum Diet Prevents Bone Loss Caused by Ionizating Radiation: Reduces Pro-Resorption Cytokine Expression, and Protects Marrow-Derived Osteoprogenitors

Future long duration missions outside the protection of the Earth's magnetosphere, or unshielded exposures to solar particle events, achieves total doses capable of causing cancellous bone loss. Cancellous bone loss caused by ionizing radiation occurs quite rapidly in rodents: Initially, radiation increases the number and activity of bone-resorbing osteoclasts, followed by decrease in bone forming osteoblast cells. Here we report that Dried Plum (DP) diet completely prevented cancellous bone loss caused by ionizing radiation (Figure 1). DP attenuated marrow expression of genes related to bone resorption (Figure 2), and protected the bone marrow-derived pre-osteoblasts ex vivo from total body irradiation (Figure 3). DP is known to inhibit resorption in models of aging and ovariectomy-induced osteopenia; this is the first report that dietary DP is radioprotective

Household Responses to Pandemic (H1N1) 2009–related School Closures, Perth, Western Australia

Results from closures will determine the appropriateness and efficacy of this mitigation measure