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This study examined the effect of acute acetaminophen (ACTP) ingestion on physical performance during the 5 m shuttle run test (5mSRT), attention, mood states, and the perception of perceived exertion (RPE), pain (PP), recovery (PRS), and delayed onset of muscle soreness (DOMS) in well-trained female athletes. In a randomized, placebo-controlled, double-blind, crossover trial, fifteen well-trained female athletes (age 21 ± 2 years, height 165 ± 6 cm, body mass 62 ± 5 kg) swallowed either 1.5 g of ACTP or 1.5 g of placebo. The profile of mood states (POMS) and digit cancellation (DCT) were assessed 45 min postingestion, and 5mSRT was performed 60 min postingestion. The RPE and PP were determined immediately after each 30-s repetition of the 5mSRT, and the PRS and DOMS were recorded at 5 min and 24 h post-5mSRT. For the 5mSRT, ACTP ingestion improved the greatest distance (+ 10.88%, p < 0.001), total distance (+ 11.33%, p = 0.0007) and fatigue index (+ 21.43%, p = 0.0003) compared to PLA. Likewise, the DCT score was better on the ACTP (p = 0.0007) than on the PLA. RPE, PP, PRS, and DOMS scores were improved after ACTP ingestion (p < 0.01 for all comparisons) compared to PLA. POMS scores were enhanced with ACTP ingestion compared to PLA (p < 0.01). In conclusion, this study indicates that acute acetaminophen ingestion can improve repeated high intensity short-term maximal performance, attention, mood states, and perceptions of exertion, pain, recovery, and muscle soreness in well-trained female athletes, suggesting potential benefits for their overall athletic performance and mood state.

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The role of erythropoietin (EPO) has extended beyond hematopoiesis to include cytoprotection, inotropy, and neurogenesis. Extra-renal EPO has been reported for multiple tissue/cell types, but the physiological relevance remains unknown. Although the EPO receptor is expressed by multiple cardiac cell types and human recombinant EPO increases contractility and confers cytoprotection against injury, whether the heart produces physiologically meaningful amounts of EPO in vivo is unclear. We show a distinct circadian rhythm of cardiac EPO mRNA expression in adult mice and increased mRNA expression during embryogenesis, suggesting physiological relevance to cardiac EPO production throughout life. We then generated constitutive, cardiomyocyte-specific EPO knockout mice driven by the Mlc2v promoter (EPOfl/fl:Mlc2v-cre+/-; EPOΔ/Δ-CM). During cardiogenesis, cardiac EPO mRNA expression and cellular proliferation were reduced in EPOΔ/Δ-CM hearts. However, in adult EPOΔ/Δ- CM mice, total heart weight was preserved through increased cardiomyocyte cross-sectional area, indicating the reduced cellular proliferation was compensated for by cellular hypertrophy. Echocardiography revealed no changes in cardiac dimensions, with modest reductions in ejection fraction, stroke volume, and tachycardia, whereas invasive hemodynamics showed increased cardiac contractility and lusitropy. Paradoxically, EPO mRNA expression in the heart was elevated in adult EPOΔ/Δ-CM, along with increased serum EPO protein content and hematocrit. Using RNA fluorescent in situ hybridization, we found that Epo RNA colocalized with endothelial cells in the hearts of adult EPOΔ/Δ-CM mice, identifying the endothelial cells as a cell responsible for the EPO hyper-expression. Collectively, these data identify the first physiological roles for cardiomyocyte-derived EPO. We have established cardiac EPO mRNA expression is a complex interplay of multiple cell types, where loss of embryonic cardiomyocyte EPO production results in hyper-expression from other cells within the adult heart.

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Developmental exposure of turtles and other reptiles to endocrine disrupting chemicals (EDCs), including bisphenol A (BPA) and ethinyl estradiol (EE2, estrogen present in birth control pills), can induce partial to full gonadal sex-reversal in males. No prior studies have considered whether in ovo exposure to EDCs disrupts normal brain sexual differentiation. Yet, rodent model studies indicate early exposure to these chemicals disturbs sexually selected behavioral traits, including spatial navigational learning and memory. Thus, we sought to determine whether developmental exposure of painted turtles (Chrysemys picta) to BPA and EE2 results in sex-dependent behavioral changes. At developmental stage 17, turtles incubated at 26°C (male-inducing temperature) were treated with 1) BPA High (100µg /mL), 2) BPA Low (0.01µg/mL), 3) EE2 (0.2µg/mL), or 4) vehicle or no vehicle control groups. Five months after hatching, turtles were tested with a spatial navigational test that included four food containers, only one of which was baited with food. Each turtle was randomly assigned one container that did not change over the trial period. Each individual was tested for 14 consecutive days. Results show developmental exposure to BPA High and EE2 improved spatial navigational learning and memory, as evidenced by increased number of times spent in the correct target zone and greater likelihood of solving the maze compared to control turtles. This study is the first to show that in addition to overriding temperature sex determination (TSD) of the male gonad, these EDCs may induce sex-dependent behavioral changes in turtles.

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BACKGROUND: As part of a study of whole-body protein metabolism in hemodialysis (HD) patients, we obtained values for whole-body bicarbonate production in control subjects and HD patients before and during dialysis by using stable isotopically labeled bicarbonate. Indirect calorimetry measurements have shown normal or increased energy expenditure in HD patients, which has been used to explain the malnutrition in many of these patients. However, this method becomes inaccurate when the dynamics of whole-body bicarbonate production change during measurement, as is the case with HD patients during dialysis. METHODS: Whole-body bicarbonate production was measured in 6 control subjects, 9 patients on a nondialysis day (HD-), and 8 patients during an HD session (HD+) by means of a primed constant infusion of carbon 13 (13C)-labeled sodium carbonate (NaH13CO3). 13C-abundance of expired carbon dioxide was measured by means of isotope ratio mass spectrometry. RESULTS: Carbon dioxide production was 141 +/- 12, 123 +/- 11*, and 148 +/- 19 micromol/kg/min for the control, HD-, and HD+ groups, respectively (*P < 0.05 compared with the control and HD+ groups). Values for energy expenditure were derived and were 29.1 +/- 2.4, 24.9 +/- 2.1*, and 32.6 +/- 2.0 kcal/kg/day, respectively (*P < 0.05 compared with the control and HD+ groups). CONCLUSION: Whole-body oxidation in HD patients is reduced compared with control subjects. During dialysis, bicarbonate turnover, as well as carbon dioxide expiration, increases because of the influx of bicarbonate from the dialyzer.

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BACKGROUND: Protein-calorie malnutrition is present in 30-50% of dialysis patients. The lack of biocompatibility of the dialysis membrane, which results in low-grade inflammation, could be responsible for this malnutrition. We investigated whether protein-energy malnutrition could be partly due to incompatibility of the dialyzer during the dialysis session. METHODS: Five patients were dialyzed during 2 periods of 3 weeks (cross-over) with either a single-use low-flux polysulfone or cellulose triacetate (biocompatible) or a single-use cuprophan (bio-incompatible) membrane. As a measure of whole body protein metabolism, a primed constant infusion of L-[1-(13)C]-valine was used during a 4-hour dialysis session. RESULTS: Cuprophan was a more powerful activator of the complement system than other membranes. Protein metabolism parameters during both study protocols were not different and resulted in the same protein balance during polysulfone/cellulose triacetate (-15 +/- 3) and cuprophan (-13 +/- 2 micromol/kg/h) dialysis. CONCLUSION: In stable hemodialysis patients with no apparent complications, protein metabolism during dialysis is not affected by the compatibility of the dialysis membrane.

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BACKGROUND: The PNA (protein equivalent of nitrogen appearance) is used to calculate protein intake from urea kinetics. One of the essential assumptions in the calculation of PNA is that urea accumulation in haemodialysis (HD) patients is equivalent to amino acid oxidation. However, urea is hydrolysed in the intestine and the resulting ammonia could be used metabolically. The magnitude and dependence on protein intake of this process are unknown in HD patients. METHODS: Seven HD patients were studied twice, 1 week apart, on a similar protocol. After an overnight fast, patients fasted in the morning and received meals in the afternoon. On one day, amino acid oxidation was measured by infusion of L-[1-(13)C]valine. Urea production, measured from the dilution of [(13)C]urea, and urea accumulation, calculated from the increase in plasma urea concentration multiplied by the urea dilution volume, were measured during the other day. PNA was calculated using standard equations. RESULTS: Amino acid oxidation and urea production were not significantly different during fasting. Urea accumulation during fasting was significantly lower than both amino acid oxidation and urea production. Urea accumulation during feeding remained significantly lower than amino acid oxidation. PNA was equal to the average of the urea accumulation values during fasting and feeding. CONCLUSION: We conclude that during fasting, urea accumulation is not associated with amino acid oxidation or urea production. During meal intake, amino acid oxidation, urea production and urea accumulation show acutely an almost identical increase. PNA represents the average of fasting and fed urea accumulation and is lower than average amino acid oxidation or urea production.

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BACKGROUND: Protein-energy malnutrition affects 30% to 50% of hemodialysis (HD) patients. This has been attributed to inadequate food intake, but may be caused by disturbances in utilization of ingested protein. METHODS: We studied protein kinetics during fasting and during ingestion of a protein-enriched meal to investigate possible metabolic differences between stable HD patients and control subjects. Whole-body protein kinetics was measured by means of a primed constant infusion of L[1-13C] valine. RESULTS: During fasting, whole-body protein balance was significantly less negative in HD patients compared with control subjects. During meal intake, protein balance was similar between HD patients and control subjects. Meal intake increased protein balance significantly in both groups, but not differently between the groups. Also, protein oxidation was decreased during fasting in HD patients compared with control subjects, but not during meal intake. CONCLUSION: We conclude that the rate of protein breakdown is lower in HD patients compared with control subjects, but the efficiency of protein utilization is normal in HD patients during a nondialysis day.

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Protein energy malnutrition is present in 18 to 56% of hemodialysis patients. Because hemodialysis has been regarded as a catabolic event, we studied whether consumption of a protein- and energy-enriched meal improves the whole body protein balance during dialysis in chronic hemodialysis (CHD) patients. Patients were studied on a single day between dialysis (HD- protocol) in the morning while fasting and in the afternoon while consuming six small test meals. Patients were also studied during two separate dialysis sessions (HD+ protocol). Patients were fasted during one and consumed the meals during the other. Whole body protein metabolism was studied by primed constant infusion of l-[1-(13)C]valine. During HD-, feeding changed the negative whole body protein balance observed during fasting to a positive protein balance. Dialysis deepened the negative balance during fasting, whereas feeding during dialysis induced a positive balance comparable to the HD- protocol while feeding. Plasma valine concentrations during the studies were correlated with whole body protein synthesis and inversely correlated with whole body protein breakdown. We conclude that the consumption of a protein- and energy-enriched meal by CHD patients while dialyzing can strongly improve whole body protein balance, probably because of the increased amino acid concentrations in blood.

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Nurse practitioners (NPs) have been the subjects of many studies focused on role performance, cost effectiveness, and acceptance in clinical practice. As part of a study to compare successful entry of NP program graduates from various backgrounds into NP practice, a review of the literature was performed. This literature review focuses on research studies that examine successful entry into NP practice by seasoned registered nurses as well as by non-nurse college graduates who have no prior nursing experience. The topical areas that emerged from the literature were educational background and experience as a registered nurse, socialization into practice, transition into NP practice, and evaluation measures of successful NP practice. The results of the literature review revealed the need for further work on assessment of successful entry into NP practice.

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The authors report a case of a 2-month-old girl diagnosed with Beckwith-Wiedemann syndrome (BWS) who was born prematurely and died suddenly in the hospital just before being discharged. BWS is a malformation syndrome associated with an increased risk of childhood tumors. The major features of BWS are macroglossia, abdominal wall defects, and visceromegaly, frequently leading to premature birth. Due to complex inheritance patterns, a predominance of nonfamilial cases, and the variability in expression of the features (termed incomplete penetrance), the risk of delayed diagnosis is evident. Secondary to hyperplastic pancreatic islands, hypoglycemia occurs frequently, and if not anticipated, adequate measures for prevention of hypoglycemic episodes may be delayed, resulting in possible intellectual deficits. The infant presented here died of natural causes: immaturity of the lungs resulting in marginal respiratory function and compounded by increased risk for asphyxia secondary to the enlarged tongue. The clinical history and findings in this infant are discussed in respect to the genetic syndrome with their relevance to medicolegal examination and the causes and manner of death.

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A Podospora anserina mitochondrial DNA (mtDNA) rearrangement mutant, Mn19, was crossed with a deletion mutant, alphaDelta5. Ascospores (212) from random asci were tested for viability, growth and life-span phenotypes, and mtDNA inheritance. Some spore inviability was detected along with early growth arrest (at the time of spore germination) from which some isolates recovered. However, the majority had wild-type growth and life-span phenotypes. All isolates tested at the DNA level (102) had wild-type mtDNA hybridization patterns with probes that detected defects in the parents. About 20% also inherited low levels of mtDNA molecules with the rearrangement characteristic of the Mn19 parent. These results demonstrate that P. anserina has a remarkable ability, through sexual reproduction, to restore its mtDNA to wild-type, even when the parents are predominately mutant.

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