Stability, Composition, and Core-Shell Particle Structure of Uranium(IV)-Silicate Colloids.

Uranium is typically the most abundant radionuclide by mass in radioactive wastes and is a significant component of effluent streams at nuclear facilities. Actinide(IV) (An(IV)) colloids formed via various pathways, including corrosion of spent nuclear fuel, have the potential to greatly enhance the mobility of poorly soluble An(IV) forms, including uranium. This is particularly important in conditions relevant to decommissioning of nuclear facilities and the geological disposal of radioactive waste. Previous studies have suggested that silicate could stabilize U(IV) colloids. Here the formation, composition, and structure of U(IV)-silicate colloids under the alkaline conditions relevant to spent nuclear fuel storage and disposal were investigated using a range of state of the art techniques. The colloids are formed across a range of pH conditions (9-10.5) and silicate concentrations (2-4 mM) and have a primary particle size 1-10 nm, also forming suspended aggregates <220 nm. X-ray absorption spectroscopy, ultrafiltration, and scanning transmission electron microscopy confirm the particles are U(IV)-silicates. Additional evidence from X-ray diffraction and pair distribution function data suggests the primary particles are composed of a UO2-rich core and a U-silicate shell. U(IV)-silicate colloids formation correlates with the formation of U(OH)3(H3SiO4)32- complexes in solution indicating they are likely particle precursors. Finally, these colloids form under a range of conditions relevant to nuclear fuel storage and geological disposal of radioactive waste and represent a potential pathway for U mobility in these systems.

Nanostructured Aptamer-Functionalized Black Phosphorus Sensing Platform for Label-Free Detection of Myoglobin, a Cardiovascular Disease Biomarker.

We report the electrochemical detection of the redox active cardiac biomarker myoglobin (Mb) using aptamer-functionalized black phosphorus nanostructured electrodes by measuring direct electron transfer. The as-synthesized few-layer black phosphorus nanosheets have been functionalized with poly-l-lysine (PLL) to facilitate binding with generated anti-Mb DNA aptamers on nanostructured electrodes. This aptasensor platform has a record-low detection limit (∼0.524 pg mL(-1)) and sensitivity (36 µA pg(-1) mL cm(-2)) toward Mb with a dynamic response range from 1 pg mL(-1) to 16 µg mL(-1) for Mb in serum samples. This strategy opens up avenues to bedside technologies for multiplexed diagnosis of cardiovascular diseases in complex human samples.

Multivalent linkers for improved covalent binding of oligonucleotides to dye-doped silica nanoparticles.

This paper describes the fabrication of oligonucleotide-coated Cy5-doped silica nanoparticles using a combination of multivalent linkers and their use in surface-based DNA sandwich hybridization assays. Dipodal silane is introduced as a means to fabricate amine-coated silica nanoparticles and its advantages compared to monopodal silanes are discussed. The use of dipodal silane in conjunction with three different polymer linkers (oxidized dextran, linear and 8-arm polyethylene glycol (PEG)) to immobilize single-stranded DNA to Cy5-doped nanoparticles is investigated and dynamic light scattering measurements and Fourier transform infrared spectroscopy are used to follow the progression of the functionalization of the nanoparticles. We observe a significant improvement in the binding stability of the single-stranded DNA when the dipodal silane and 8-arm PEG are used in combination, when compared to alternative conjugation strategies. Both 8mer and 22mer oligonucleotides are securely conjugated to the high-brightness nanoparticles and their availability to hybridize with a complementary strand is confirmed using solution-based DNA hybridization experiments. In addition, a full surface-based sandwich assay demonstrates the potential these nanoparticles have in the detection of less than 500 femtomolar of a DNA analogue of micro RNA, miR-451.

Nutrient removal in a sequencing batch biofilm reactor (SBBR) using a vertically moving biofilm system.

In this paper, the performance of a sequencing batch biofilm reactor (SBBR) using an anoxic/anaerobic phase followed by an aerobic phase for nutrient removal from wastewater was investigated. In the laboratory SBBR unit, biofilm was grown on a plastic biofilm media module, which was vertically moved up into the air and down into the bulk fluid during the aerobic phase. The vertical movement of the biofilm module supplied oxygen to the microorganisms. The module was submerged in the wastewater during the anoxic/anaerobic phase. The percentage removals of total chemical oxygen demand (COD), total nitrogen (TN) and soluble orthophosphate (PO4-P) were 95.4%, 68.3% and 89.5% respectively at influent concentrations of COD 773 mg l(-1), TN 49.9 mg l(-1) and PO4-P 16.5 mg l(-1). The effluent COD was 35 mg l(-1), NH4-N 10.2 mg l(-1), NO3-N 5.5 mg l(-1), soluble PO4-P 1.7 mg l(-1) and suspended solids (SS) 19 mg l(-1).

Redox-regulated mechanism may account for zerumbone's ability to suppress cancer-cell proliferation.

A recent report shows that zerumbone (ZER) inhibits the proliferation of, and induces apoptosis in, colon cancer cells. We suggest a mechanism for these phenomena, based on our recently proposed redox model of cell proliferation which stresses the importance of intracellular redox potential E in the control of proliferation of normal and cancer cells.

Preclinical efficacy and safety of pascolizumab (SB 240683): a humanized anti-interleukin-4 antibody with therapeutic potential in asthma.

The type 2 helper T cell (T(H)2) cytokine interleukin (IL)-4 is thought to play a central role in the early stages of asthma. In an effort to develop an antibody treatment for asthma that neutralizes the effects of IL-4, a murine monoclonal antibody, 3B9, was generated with specificity for human IL-4. In vitro studies demonstrated that 3B9 inhibited IL-4-dependent events including IL-5 synthesis, (T(H)2) cell activation and up-regulation of immunoglobulin E expression. 3B9 was then humanized (pascolizumab, SB 240683) to reduce immunogenicity in humans. SB 240683 demonstrated species specificity for both monkey and human IL-4 with no reactivity to mouse, rat, cow, goat or horse IL-4. Pascolizumab inhibited the response of human and monkey T cells to monkey IL-4 and effectively neutralized IL-4 bioactivity when tested against several IL-4-responsive human cell lines. Affinity studies demonstrated rapid IL-4 binding by pascolizumab with a slow dissociation rate. In vivo pharmacokinetic and chronic safety testing in cynomolgus monkeys demonstrated that pascolizumab was well tolerated, and no adverse clinical responses occurred after up to 9 months of treatment. Three monkeys developed an anti-idiotypic response that resulted in rapid pascolizumab clearance. However, in the chronic dosing study the antibody response was transient and not associated with clinical events. In conclusion, pascolizumab is a humanized anti-IL-4 monoclonal antibody that can inhibit upstream and downstream events associated with asthma, including (T(H)2) cell activation and immunoglobulin E production. Clinical trials are under way to test the clinical efficacy of pascolizumab for asthma.

Dietary uptake of lycopene protects human cells from singlet oxygen and nitrogen dioxide - ROS components from cigarette smoke.

There is current interest in the health benefits of dietary carotenoids and the possible deleterious effects on certain sub-populations such as smokers. Here we report in vivo protection of human lymphocytes, conferred by dietary supplementation of lycopene rich foods against the reactive oxygen species, NO(2)(*) radical (by electron transfer) and 1(O)(2) (by energy transfer). It was found that a lycopene rich diet, maintained for 14 days, increased the serum lycopene level 10 fold compared to serum obtained after the same period, where a typical western European diet had been consumed. Relative lymphocyte protection factors of 17.6 and 6.3 against NO(2)(*) radical and 1(O)(2), respectively, were obtained, which re-enforce epidemiological data, showing protection against several chronic diseases by tomato lycopene.

Duplication of the hypophysis.

The authors describe an 11-year-old girl with duplication of a pituitary gland and hypertelorism. Of the 14 cases described to date, only 2 others have lacked associated major facial or oral anomalies. Two separate glands, respective stalks and hypothalamic enlargement were incidentally found on MR imaging performed to evaluate the patient's complaint of anosmia. A tortuous fusiform dilatation of one pericallosal artery was also discovered. A review of hypophyseal embryogenesis is presented. It is now evident that duplication of the pituitary can occur without other major dysmorphias. This may infer that notochord/prochordal plate deficits are not a prerequisite for hypophyseal duplication.

Facilitation of electric forepaw stimulation-induced somatosensory activation in rats by additional acoustic stimulation: an fMRI investigation.

The influence of scanner acoustic noise on somatosensory activation pattern in rat cortex was investigated by functional magnetic resonance imaging (fMRI) using the blood oxygenation level-dependent (BOLD) contrast. This was achieved by two approaches. The first approach was to compare a conventional, loud fMRI sequence with a new sequence, in which the noise level was reduced by about 30 dB. In the second approach, the inner ear of the animal was destroyed, resulting in deafness. We compared the activation patterns obtained with both sequences before and after cochleotomy. The activated area was larger when data were sampled with background noise, and was also larger before cochleotomy than after. Thus, facilitation of somatosensory activation is induced by additional acoustic stimulation. Magn Reson Med 44:317-321, 2000.

Measurement of protein interaction bioenergetics: application to structural variants of anti-sCD4 antibody.

This chapter has described a bioenergetic analysis of the interaction of sCD4 with an IgG1 and two IgG4 derivatives of an anti-sCD4 MAb. The MAbs have identical VH and VL domains but differ markedly in their CH and CL domains, raising the question of whether their antigen-binding chemistries are altered. We find the sCD4-binding kinetics and thermodynamics of the MAbs are indistinguishable, which indicates rigorously that the molecular details of the binding interactions are the same. We also showed the importance of using multiple biophysical methods to define the binding model before the bioenergetics can be appropriately interpreted. Analysis of the binding thermodynamics and kinetics suggests conformational changes that might be coupled to sCD4 binding by these MAbs are small or absent.

High-dose intravenous magnesium attenuates complement consumption after acute myocardial infarction treated by streptokinase.

OBJECTIVE: This study was designed to detect changes in complement levels following acute myocardial infarction and to test whether magnesium sulphate (MgSO4) administration interferes with the complement response that follows acute myocardial infarction. DESIGN: Twenty-nine patients with acute myocardial infarction treated with streptokinase were included and randomly assigned to three treatment groups. In groups A and B, a bolus of 1 g MgSO4 was infused intravenously followed by 4 g (group A) and 14 g (group B) MgSO4 for 24 h while normal saline was administered in group C (control). Blood samples for C3, C4 and CH-100 were obtained at baseline and repeatedly during the 48 h following the initiation of magnesium infusion. RESULTS: In groups A and C, a remarkable decrease in the levels of C3, C4 and CH-100 was observed when measured 1 h after the end of streptokinase infusion and thereafter for the ensuing 48 h compared to baseline values (P < 0.05). In group B, the decrease in these complement elements was attenuated, and a significant (P < 0.05) delayed decrease of C3 and C4 was observed only at 24 h and later up to 48 h. The mean level of CH-100 in group B was significantly depressed compared to baseline from 3 h and thereafter up to 48 h. Mean C3 values plotted against observation time differed between the three groups (P = 0.021). A similar trend was observed for C4 (P = 0.133) but not for CH-100 (P = 0.46). CONCLUSION: (1) Complement elements are being consumed following acute myocardial infarction treated by streptokinase. (2) High-dose intravenous magnesium attenuates the complement process following acute myocardial infarction. (3) These results might signify that magnesium modulates the inflammatory response that follows infarction.

Music therapy following suctioning: four case studies.

This descriptive study evaluates and compares the effectiveness of music, presented both aurally and vibrotactilely, in reducing agitation and physiological instability following a stress-producing intervention (suctioning) in infants with bronchopulmonary dysplasia. Heart rate, oxygen saturation levels, level of arousal, stressful facial expressions, and autonomic indicators were recorded for each of four preterm infants. All infants experienced a reduction in the level of arousal during the taped music intervention when compared with the control condition. Three infants spent an increased amount of time in a quiet alert state and had improved oxygen saturation levels during the vibrotactile intervention. All infants spent more time sleeping during the taped music condition than without music or with the vibrotactile intervention. Results suggest that music is effective in reducing stress-related behaviors for some infants.

Age-related vulnerability of developing cholinergic basal forebrain neurons following excitotoxic lesions of the hippocampus.

Previous studies have demonstrated that depleting the hippocampus of endogenous neurotrophins via excitotoxic lesions fails to alter the viability of adult cholinergic septal/diagonal band neurons. Since cholinergic basal forebrain neurons may be more vulnerable during development, we investigated whether excitotoxic lesions produced in neonatal animals alter the viability of these cells. Postnatal Day 7, 10, 14, and 28 rats pups received unilateral intrahippocampal injections of ibotenic acid and were sacrificed 4 weeks later. At 7, 10, and 14 days of age, significant reductions in the number of choline acetyltransferase (ChAT)- and p75 nerve growth factor receptor (NGFr)-immunoreactive neurons were observed within the medial septum ipsilateral to the hippocampal lesion. In contrast, rats receiving similar lesions on Day 28 failed to display a significant reduction in ChAT-immunoreactive medial septal neurons. The magnitude of ChAT-immunoreactive neuronal loss within the medial septum and the age at which the lesion was made were inversely correlated (r2 = 0.887), indicating that cholinergic septal neurons become less vulnerable to target removal as the cells develop. Similar results were observed in the vertical limb of the diagonal band although a small but significant loss of ChAT-immunoreactive neurons was seen in this structure ipsilateral to the hippocampal lesion when lesions were performed on Postnatal Day 28. At all age groups, many remaining cholinergic septal/diagonal band neurons appeared dystrophic with stunted fiber outgrowth. The present study demonstrates that unlike adult rats, removal of hippocampal target neurons during development alters the viability and morphology of cholinergic neurons of the medial septum and diagonal band. This suggests that target neurons which synthesize endogenous neurotrophins are needed for normal development of cholinergic basal forebrain neurons, but may not be required for the normal maintenance of the adult cell.

A nursing rehabilitation program for women with breast cancer receiving adjuvant chemotherapy.

PURPOSE/OBJECTIVES: To examine the effects of a comprehensive rehabilitation program on facilitating physical and psychosocial adaptation of women with breast cancer who are receiving adjuvant chemotherapy. DESIGN: Experimental. SETTING: Breast evaluation clinics of two New England medical centers with comprehensive cancer treatment programs. SAMPLE: 14 women (mean age = 44 years) receiving adjuvant chemotherapy for breast cancer (86% stage II) following surgical treatment. METHODS: Subjects were assigned randomly to the experimental group or the usual care group. Experimental group members began a structured exercise program of walking and attended support group meetings. All subjects were tested before beginning chemotherapy, during the course of chemotherapy, and one month following chemotherapy completion. MAIN RESEARCH VARIABLES: Performance status, physical functioning, psychosocial adjustment, self-concept and body image, and 12 symptoms (e.g., fatigue, nausea, anxiety). FINDINGS: Measures of physical performance, psychosocial adjustment, and symptom intensity revealed improved adaptation in subjects who completed the walking/support group program. CONCLUSIONS: Physical and psychosocial benefits from a modest walking exercise program and a support group are possible for patients receiving adjuvant chemotherapy. IMPLICATIONS FOR NURSING PRACTICE: Although more detailed research is necessary to answer some of the questions raised by this study, implementing the walking program and forming a support group are achievable in an outpatient setting.

Chronic renal disease and pregnancy.

Women who have chronic renal disease are at increased risk for maternal and fetal morbidity and mortality during pregnancy. The severity of the renal disease is correlated with the degree of morbidity and mortality. Chronic renal disease ranges from asymptomatic bacteriuria (ASB) to end stage renal disease requiring hemodialysis and/or renal transplantation. Pregnant women with chronic renal disease require specialized nursing care. Communication between obstetrical nurses and renal nurses is extremely important to ensure holistic care of these patients.

Calcium and phosphorus studies: interpretation of results and strategies for further testing.

Persistent hypercalcemia is most often due to tumor. Other causes are best eliminated by clinical methods combined with simple tests. Hypocalcemia is most often a result of hypoalbuminemia. Hyperphosphatemia induced by phosphate infusion or enema may cause profound hypocalcemia. Biochemical profiling may uncover severe hypophosphatemia necessitating phosphate administration. Markedly elevated serum alkaline phosphatase in the absence of hepatic disease is most likely to reflect either Paget's disease of bone or metastatic prostate cancer.

Dietary intakes, resting metabolic rates, and body composition in benign and malignant gastrointestinal disease.

Dietary protein and energy intakes were assessed in 42 patients with cancer and 24 with benign conditions of the gastrointestinal tract. The relations of dietary intake to body composition was examined. Resulting metabolic rate was measured in 51 patients. No significant differences in dietary intake or metabolic rate were found between patients with cancer and those with benign disease. There were significant positive correlations between protein and energy intakes and the ratio of total body potassium to total body water in patients with benign disease but not in those with cancer. Weight loss was probably due to inadequate food intake, the main defect being energy deficiency, since protein intake was usually well maintained. Supplementing with energy the voluntary ingested diet of patients with cancer would probably prevent weight loss in most cases.

Home parenteral nutrition: an alternative approach to the management of complicated gastrointestinal fistulas not responding to conventional medical or surgical therapy.

Twelve patients, 9 with enterocutaneous fistulas and 3 with enterovaginal fistulas, were placed on a home parenteral nutrition (HPN) program after conventional inpatient total parenteral nutrition with bowel rest and/or surgical attempts at fistula closure failed. Fistula closure was achieved (in 66%) after from 28 to 400 days on the program. Six closed spontaneously while 2 were closed surgically. Underlying inflammation in the bowel and the persistence of fistula drainage beyond 180 days were indicative of poor prognosis for closure. Number, location, and volume of drainage were not useful prognostic indices. HPN offers an alternative approach in the management of "intractable" gastrointestinal fistulas.