Rumen function and grazing behavior of early-lactation dairy cows supplemented with fodder beet.

Fodder beet (FB) is a source of readily fermentable carbohydrate that can mitigate early spring herbage deficits and correct the negative energy balance experienced during early lactation in pastoral dairy systems of New Zealand. However, the low-fiber and high-soluble carbohydrate content of both FB bulb and spring herbage are factors that promote subacute ruminal acidosis, impairing rumen function and limiting the marginal milk production response to supplement. In a crossover experiment, 8 Holstein Friesian × Jersey early-lactation dairy cows were used to test the effect of supplementing 16 kg of dry matter (DM) of a grazed perennial ryegrass herbage with 6 kg of DM/d of FB bulb (FBH) versus herbage only (HO) on changes in rumen function and grazing behavior. Following 20 d of adaptation to diets, DM disappearance (%) of FB bulb (FBH cows only) and herbage were measured in sacco, separately. Cows were fasted overnight, and the ruminal contents were bailed the following morning (~0930 h) again to determine the pool size of volatile fatty acids, ammonia, and particle size of digesta, as well as to estimate the rate of ruminal outflow and degradation of neutral detergent fiber. The FBH diet did not alter DM intake, milk yield, or milk solid (fat + protein) production compared with HO. Supplementation of herbage with FB reduced ruminal pH compared with HO between ~0800 h and 1300 h each day. During each period, 1 cow experienced severe subacute ruminal acidosis (pH <5.6 for >180 min/d) during final adaptation to the target FB allocation. The FBH diet reduced the ruminal pool of acetate and ammonia, but increased the ruminal pool of butyrate and lactate compared with HO. When fed FB, rumination and grazing time increased and grazing intensity declined compared with cows fed HO. Despite increased rumination, the comminution of large particles declined 28% between the first and second rumen bailing when cows were fed FB, and in sacco DM disappearance of perennial ryegrass declined 18% compared with cows fed HO. These results indicate that grazing dairy cows supplemented with FB (40% of daily intake) increase rumination and mastication intensity to counteract reduced ruminal degradation of ryegrass herbage due to low ruminal fluid pH.

Evaluation of essential oils and prebiotics for newborn dairy calves.

A blend of essential oils (EO; carvacrol, caryophyllene, -cymene, cineole, terpinene, and thymol) and prebiotics (arabinogalactans; Stay Strong; Ralco, Inc., Marshall, MN) was designed to promote immunity and stimulate appetite to diminish health challenges and stresses experienced by newborn calves. It was hypothesized that calves supplemented with the medium dose (2.5 g/feeding) of the commercial EO would demonstrate the optimal response. The study objective was to determine the optimal feeding rate of EO when added to a milk replacer (MR) compared with feeding a control or a yeast cell wall additive (YCW). One hundred Holstein calves from a commercial dairy farm were blocked by birth date and randomly assigned to 1 of 5 treatments. Treatments were a control (CON), a 24:20% CP:fat (as-fed basis) MR (24:20 MR) without EO; EO mixed into the 24:20 MR at a rate of 1.25 g/feeding (EO-0.5), EO mixed into the 24:20 MR at a rate of 2.5 g/feeding (EO-1.0), or EO mixed into the 24:20 MR at a rate of 3.75 g/feeding (EO-1.5); or 24:20 MR with YCW mixed in at a rate of 2 g/calf at each feeding. The 24:20 MR was fed in a bucket 2 times/d at a rate of 0.28 kg/calf daily for 14 d, which was increased to 0.43 kg/calf at 2 times/d until d 35 and then reduced to 1 time/d at d 36 to facilitate weaning at d 42. Decoquinate was added to the MR at 41.6 mg/kg for coccidiosis control. Calves were housed in individual hutches bedded with straw with ad libitum access to a 20% CP pelleted calf starter and water. All data were analyzed using PROC MIXED as a completely random design. Calves fed EO-0.5 demonstrated greater ( < 0.05) ADG (0.65, 0.71, 0.64, 0.64, and 0.63 kg/d for the CON, EO-0.5, EO-1.0, EO-1.5, and YCW, respectively) through d 56 compared with calves fed EO-1.0 and YCW and tended ( < 0.10) to have greater ADG than calves fed the CON and EO-1.5. Total BW gains were greater ( < 0.05) for calves fed EO-0.5 compared with calves fed EO-1.0 and YCW, with calves fed the CON and EO-1.5 being intermediate and similar. Body length and wither height gains (final - initial) were greater ( < 0.05) for calves fed EO-0.5 compared with calves fed the other treatments. Hip width gains were similar ( < 0.10) among treatments. Hip height gains were increased ( < 0.05) for calves fed EO-0.5 compared with calves fed the CON, EO-1.0, EO-1.5, and YCW. These results demonstrate that supplementing EO-0.5 (1.25 g/calf daily) in a 24:20 MR may be the optimal feeding rate to enhance growth rates compared with feeding a 24:20 MR and a 24:20 MR containing YCW or other inclusion rates of EO.

Influence of leg position on the depth and sonographic appearance of the sciatic nerve in volunteers.

We investigated the effect of leg position on the depth of the sciatic nerve and quality of ultrasound images taken at the proximal and mid-thigh level. Twenty-one volunteers with average body mass index were recruited to represent the younger population receiving sciatic nerve blocks for sports injury surgery. The volunteers were placed in the lateral position, with the hip flexed and with the hip in a neutral (extended) position. A single operator imaged the uppermost leg and the best images of the sciatic nerve at the proximal and mid-thigh level were saved. Sciatic nerve depth was measured at each level. Eleven clinicians experienced in ultrasound-guided regional anaesthesia assessed the paired images. In the proximal thigh, the sciatic nerve depth was greater with the hip flexed compared to the neutral position (median 30 vs 23 mm, P = 0.0002). There was no consistent difference in the mid-thigh. More clinicians favoured the proximal sciatic image with the leg in the neutral position. Although statistically significant, the depth difference is probably not a major clinical consideration in most patients with an average body mass index. We suggest clinicians place the leg in the most ergonomically favourable position when performing sciatic nerve blocks in the proximal thigh in these patients.

The co-translocation of ERp57 and calreticulin determines the immunogenicity of cell death.

The exposure of calreticulin (CRT) on the plasma membrane can precede anthracycline-induced apoptosis and is required for cell death to be perceived as immunogenic. Mass spectroscopy, immunofluorescence and immunoprecipitation experiments revealed that CRT co-translocates to the surface with another endoplasmic reticulum-sessile protein, the disulfide isomerase ERp57. The knockout and knockdown of CRT or ERp57 inhibited the anthracycline-induced translocation of ERp57 or CRT, respectively. CRT point mutants that fail to interact with ERp57 were unable to restore ERp57 translocation upon transfection into crt(-/-) cells, underscoring that a direct interaction between CRT and ERp57 is strictly required for their co-translocation to the surface. ERp57(low) tumor cells generated by retroviral introduction of an ERp57-specific shRNA exhibited a normal apoptotic response to anthracyclines in vitro, yet were resistant to anthracycline treatment in vivo. Moreover, ERp57(low) cancer cells (which failed to expose CRT) treated with anthracyclines were unable to elicit an anti-tumor response in conditions in which control cells were highly immunogenic. The failure of ERp57(low) cells to elicit immune responses and to respond to chemotherapy could be overcome by exogenous supply of recombinant CRT protein. These results indicate that tumors that possess an intrinsic defect in the CRT-translocating machinery become resistant to anthracycline chemotherapy due to their incapacity to elicit an anti-cancer immune response.

Marine radioactivity assessment of Mururoa and Fangataufa atolls.

The International Atomic Energy Agency (IAEA) carried out an international project. 'The Study of the Radiological Situation at the Atolls of Mururoa and Fangataufa' with the aim of assessing the present and future radiological situation at the atolls and making recommendations for either monitoring or remedial actions if they are deemed necessary. The paper concentrates on marine radioactivity aspects and gives an estimation of present radionuclide concentrations in water, sediment and biota of the Mururoa and Fangataufa lagoons and the surrounding ocean. The dominant radionuclide in both lagoons is Pu in sediments (the total inventory is approximately 30 TBq). A decline in radionuclide concentrations has been observed in recent years in lagoon water, with the exception of 3H and 90Sr, for which a contribution from underground sources is to be expected. Radionuclide concentrations in biota from the lagoons and the surrounding ocean are low and consistent with previous measurements. The observed radionuclide concentrations in both lagoons imply that no radiological risk exists for hypothetical inhabitants of Mururoa and Fangataufa Atolls.

Isotope studies in the Caspian Sea.

Oceanographic and isotopic investigations in the Caspian Sea and the analyses of the available data on the discharge to the sea and the observed sea level changes suggest that climatically caused changes of river inflow are the major cause of the sea level fluctuations over the last century. Hydrogen-3 and 3H-3He data indicate that the deep basins of the sea are rapidly ventilated, although the hydraulic turnover time of the sea is approximately 200 years. The concentration levels of the anthropogenic radionuclides 90Sr, 137Cs and 239,240Pu in the water column can be explained by global fallout and therefore, at the sampling sites visited, there were no signs of dumping of radioactive wastes. The anthropogenic radionuclide data support the idea of fast exchange of water masses in the Caspian Sea. The isotopic and oceanographic data collected during the cruises have shown potential to allow for a better understanding of the water circulation in the Caspian Sea.

Chemical and isotopic investigation of groundwater in Tahta region, Sohag-Egypt.

Chemical and isotopic investigations indicate that the recharge source for the groundwater in the Tahta district, adjacent to the Nile, is mainly from the Nile water seeping from irrigation channels. The water's chemical type is sodium bicarbonate, with values of oxygen-18 and deuterium close to that of Nile water. Another minor source of recharge to the far west of the Nile bank is palaeowater. This water's chemical type is sodium sulphate and sodium chloride. The change of water quality in some groundwater samples could be due to the extensive use of fertilizers to improve soil characteristics in new reclamation projects. In addition, these wells are slightly depleted in oxygen-18, deuterium and tritium. Recommendations for the periodic monitoring of groundwater quality for proper use are given.

Study of environmental isotope distribution in the Aswan High Dam Lake (Egypt) for estimation of evaporation of lake water and its recharge to adjacent groundwater.

Oxygen-18 ((18)0) and deuterium isotopes were used to estimate the evaporation from the Aswan High Dam Lake and to investigate the inter-relation between the lake water and adjacent groundwater.According to stable isotopic analysis of samples taken in 1988 and 1989, the lake can be divided into two sections. In the first section extending between Abu Simbel and a point between EI-Alaki and Krosko, a remarkable vertical gradient of (18)0 and deuterium isotopic composition was observed. The second northern sector extending to the High Dam is characterised by a lower vertical isotopic gradient. In this sector in general, higher values of (18)O and deuterium contents were found at the top and lower values at the bottom. Also a strong horizontal increase of the heavy isotope content was observed. Thus, in the northern section evaporation is of dominating influence on the isotopic composition of the lake water.With the help of an evaporation pan experiment it was possible to calibrate the evaporative isotope enrichment in the lake and to facilitate a preliminary estimate of evaporative losses of lake water. The evaporation from the lake was estimated to be about 19% of the input water flow rate.The groundwater around the lake was investigated and samples from production wells and piezometers were subjected to isotopic analysis. The results indicate that recent recharge to the groundwater aquifer is limited to wells near to the lake and up to a maximum distance of about 10 km. The contribution of recent Nile water to the groundwater in these wells was estimated to range between 23 and 70%. Beyond this distance, palaeowater was observed with highly depleted deuterium and (18)0 contents, which was also confirmed by 14c dating. The age of palaeo groundwater in this area can reach values of more than 26,000 years.Recommendations are given for efficient water management of the lake water.

Computation of diagnostic data from coronary sinus pressure: a comparison between two possible models.

We have evaluated two mathematical models to describe the increase in coronary sinus pressure (CSP) following pressure controlled intermittent coronary sinus occlusion (PICSO). The models are evaluated and compared on the basis of human and canine data. Both models were fitted by non-linear least squares algorithms. Next, derived quantities, such as plateau, rise-time and mean integral of the coronary sinus pressure were calculated from the model parameters. Corresponding quantities for the two models were compared with regard to mean values, rate of successful calculation and specific features characterizing the human or canine case. One model was found to be superior for investigational purposes. The other model was found to be more stable in critical situations and is therefore suggested for usage in closed loop regulation of PICSO. Physiologically, the differences in mean values of the derived quantities between the two models were found to be negligible. The formal statistical significance of the differences is but a consequence of the large number of PICSO cycles analysed.

Intermittent coronary sinus occlusion in humans: pressure dynamics and calculation of diagnostic quantities.

Pressure controlled intermittent coronary sinus occlusion (PISCO) was applied in 30 patients undergoing coronary artery bypass surgery. The occlusion and release times were manually adjusted according to visual control of the intraoperatively monitored coronary sinus pressure. In six patients the coronary sinus measurements were additionally digitised with a personal computer before postoperative mathematical analysis, which comprised automatic detection of systolic peaks, diastolic troughs, and the calculation of derived quantities. The purpose of the analysis was (a) to assess quantitatively human coronary sinus pressure dynamics, (b) to determine whether visual control and interpretation of coronary sinus pressure rise could be replaced by a mathematical model, and (c) to ascertain whether the occlusion and release cycle lengths were adequate. Numerical estimates for intraindividual and interindividual spread of calculated quantities were produced, the mathematically obtained results were related to a possible physiological interpretation, and the most efficient method of statistical analysis was ascertained. These results form the numerical basis for a closed loop adjustment of pressure controlled intermittent coronary sinus occlusion cycling.

Computation of derived diagnostic quantities during intermittent coronary sinus occlusion in dogs.

The haemodynamic responses to pressure controlled intermittent coronary sinus occlusion (PICSO) were recorded intraoperatively in dogs. After analogue-digital conversion the data for coronary sinus pressure were submitted to numerical analysis for detection of systolic and diastolic envelopes and their subsequent fitting by a non-linear model. From the model variables derived quantities, such as plateau and rise times, were constructed so as to resemble the most important features of coronary sinus pressure rise during each occlusion-release cycle. The derived quantities were then monitored during all consecutive cycles throughout the entire experiment. In each dog the measurements were taken during normal coronary artery perfusion, left anterior descending coronary artery infarction, and reperfusion. The analysis comprise time course, stability, and physiological correlates of the derived quantities, on some of which a closed loop regulation may be based. Predicted plateaus (systolic and diastolic) and mean integrals (systolic and diastolic) were found to be stable quantities which, on subaveraging of about five successive estimates, yielded a 10% accuracy on the mean. By contrast, the rise times required subaveraging of about 15 cycles to achieve the same relative stability. It is concluded that, on subaveraging, derived quantities lend themselves for closed loop regulation input. Thus this quantitative assessment of numerical coronary sinus pressure analysis, as obtained from animal data, may lay the basis for future human application.

A Tn10-lacZ-kanR-URA3 gene fusion transposon for insertion mutagenesis and fusion analysis of yeast and bacterial genes.

We describe here a new variant of transposon Tn10 especially adapted for transposon analysis of cloned yeast genes; it can equally well be used for analysis of prokaryotic genes. We have applied this element to analysis of the LEU2, RAD50, and CDC48 genes of Saccharomyces cerevisiae. This transposon, nicknamed mini-Tn10-LUK, contains a lacZ gene without efficient transcription or translation start signals, an intact URA3 gene, and a kanR determinant. The lacZ gene can be activated by appropriate insertion of the element into an actively expressed gene. Other yeast genes can easily be substituted for URA3 in the available constructs. The mini-Tn10-LUK system has several important advantages. Transposition events occur in Escherichia coli at high frequency and into many different sites in yeast DNA. It is easy to obtain enough insertions to sensitively define the functional limits of a gene. Transposon insertions can be obtained in a single step by standard transposon procedures and can be screened immediately for phenotype either in yeast or in E. coli. The LacZ phenotypes of the insertion mutations provide a good circumstantial indication of the orientation of the target gene. Under favorable circumstances, usable lacZ protein fusions are created. Transposon insertion mutations obtained by this method directly facilitate additional genetic, functional, physical and DNA sequence analysis of the gene or region of interest.

Adopting new models for continuity of care: the ward as mini-mental-health-center.

Several years ago the staff of a traditional psychiatric ward in a Veterans Administration hospital began trying to provide continual care for their former inpatients after they left the hospital. Nursing assistants conducted basic-skills groups and other groups in board-and-care homes; staff members made themselves available to former inpatients and theri families, roommates, or board-and-care sponsors through a 24-hour telephone service and home visits; and a day-care program and follow-up groups for the ward's outpatients were set up. Later the staff establiched additional day-care and follow-up programs in a downtown satellite unit. In a recent three month period, patients made a total of 4488 visits to the satellite and hospital programs. The preceding paper discusses some of the theoretical considerations on which this program and other alternatives to traditional care are based.