Precise measurement of the positive muon anomalous magnetic moment

A precise measurement of the anomalous g value, a(mu) = (g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu+) = 11 659 202(14) (6) x 10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu)(SM) = 11 659 159.6(6.7) x 10(-10) (0.57 ppm) and a(mu)(exp) - a(mu)(SM) = 43(16) x 10(-10) in which a(mu)(exp) is the world average experimental value.

Cardiac troponin T predicts long-term outcomes in hemodialysis patients

BACKGROUND

Increased plasma troponin T (cTnT), but not troponin I (cTnI), is frequently observed in end-stage renal failure patients. Although generally considered spurious, we previously reported an associated increased mortality at 12 months.

METHODS

We studied long-term outcomes in 244 patients on chronic hemodialysis for up to 34 months, correlating the outcomes to plasma cTnT in routine predialysis samples. In addition, subsequent plasma samples at least 1 year later and within 6 months of data analysis were available in 97 patients and were used to identify patients with increasing plasma cTnT. The endpoints used were death and new or worsening coronary, cerebro-, and peripheral vascular disease and neuropathy.

RESULTS

Transplantation occurred more frequently in patients with low initial cTnT: 31%, 13%, and 3% in the groups with cTnT < 0.010, 0.010-0.099, and > or = 0.100 microg/L, respectively. In the same groups, total deaths occurred in 6%, 43%, and 59% and cardiac deaths in 0%, 14%, and 24% of patients. In patients with follow-up samples, the group with increasing cTnT had a significantly increased death (relative risk, 2.0; P = 0.028). The increase was mainly in cardiac and sudden deaths.

CONCLUSIONS

Higher plasma cTnT predicts long-term all-cause mortality in hemodialysis patients, even at concentrations < 0.100 microg/L, as does an increasing cTnT concentration over time.

Elliptic flow in Au+Au collisions at square root(S)NN = 130 GeV

Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic flow of charged particles at midrapidity in Au+Au collisions at square root(S)NN = 130 GeV using the STAR Time Projection Chamber at the Relativistic Heavy Ion Collider. The elliptic flow signal, v2, averaged over transverse momentum, reaches values of about 6% for relatively peripheral collisions and decreases for the more central collisions. This can be interpreted as the observation of a higher degree of thermalization than at lower collision energies. Pseudorapidity and transverse momentum dependence of elliptic flow are also presented.

Papillary thyroid cancer with pulmonary metastases in children: long-term prognosis

BACKGROUND

Papillary thyroid cancer (PTC) in young patients may rarely be encountered with pulmonary metastases. Previous studies have suggested that, in the pediatric population, this may not portend a lethal outcome. Our present study, children with pulmonary metastases, was designed to clarify this issue.

METHODS

Fourteen children and young adolescents (mean age, 13.5 years; range, 9.8-17 years) with PTC and pulmonary metastases were treated at our institution between 1937 and 1998. Surgical treatment consisted of total thyroidectomy (n = 10 patients), subtotal thyroidectomy (n = 3 patients), and a biopsy only procedure (n = 1 patient). All patients who underwent thyroidectomy also underwent a variety of cervical lymph node dissections, and all patients proved to have regional nodal disease. After the operation, 12 patients were treated with ablative doses of (131)I, 1 patient was treated with external beam irradiation, and all patients were placed on suppressive thyroid hormone therapy. The mean length of follow-up was 19.3 years (range, 1-45 years).

RESULTS

Regional recurrent disease developed in 2 patients (15%). No patient experienced the development of worsening pulmonary disease or extra-pulmonary metastases. All patients with recurrent disease underwent selective nodal resections. No patient died of metastatic PTC. Seven patients (50%) remain completely free of disease and are probably cured; 7 patients (50%) are asymptomatic with residual pulmonary disease.

CONCLUSIONS

A stepwise treatment approach allows long-term survival and frequent cure for young patients with PTC and concomitant pulmonary metastases.

Study of three patients with congenital adrenal hyperplasia treated by bilateral adrenalectomy

Medical management of congenital adrenal hyperplasia (CAH) patients has led to suboptimal results in most cases. High glucocorticoid doses, often needed to suppress adrenal androgen production, may lead to signs of Cushing syndrome. Incompletely suppressed androgen levels commonly lead to premature closure of growth centers, acne, virilization, precocious puberty, irregular or absent menses, and decreased fertility in female CAH patients. A newly proposed therapy for CAH patients is bilateral adrenalectomy. Three Caucasian female patients with 21-hydroxylase deficiency were treated with bilateral adrenalectomy. Two of the three procedures were accomplished laparoscopically. In each patient, medical management alone was unsuccessful. Two patients had salt-losing 21-hydroxylase deficiency. The third patient had uncontrolled hyperandrogenism complicated by obesity and glucose intolerance. All patients had low height percentiles with respect to their normalized percentiles for weight. Bone age was advanced in one patient. Androgen and renin levels were well controlled in two patients, whereas the third patient had persistent hyperandrogenism. Bilateral adrenalectomy was performed at the ages of 14, 19, and 30 years with follow-up, to date, of 25 months, 10 months, and 26 months, respectively. Postoperatively, all patients were free from hyperandrogenism. One patient experienced one episode of urosepsis precipitating an addisonian crisis. Bilateral adrenalectomy may successfully address the problems of increasing steroid requirements and hyperandrogenism in patients with severe CAH. The ability to perform this operation laparoscopically coupled with the overall metabolic benefits make bilateral adrenalectomy a reasonable alternative to lifelong androgen suppression in select patients.

Nursing home staffing and its relationship to deficiencies

OBJECTIVES

The authors examined the relationships between different types of nursing home staffing and nursing home deficiencies to test the hypothesis that fewer staff hours would be associated with higher numbers of deficiencies.

METHODS

Data were from the On-Line Survey, Certification, and Reporting System for all certified nursing homes in the United States. Regression models examined total deficiencies, quality of care, quality of life, and other deficiencies.

RESULTS

Fewer registered nurse hours and nursing assistant hours were associated with total deficiencies and quality of care deficiencies, when other variables were controlled. Fewer nursing assistant staff and other care staff hours were associated with quality of life deficiencies. Fewer administrative staff hours were associated with other deficiencies. Facilities that had more depressed and demented residents, that were smaller, and that were nonprofit or government-owned had fewer deficiencies. Facilities with more residents with urinary incontinence and pressure sores and with higher percentages of Medicaid residents had more deficiencies, when staffing and resident characteristics were controlled.

DISCUSSION

Facility characteristics and states were stronger predictors of deficiencies than were staffing hours and resident characteristics. Because only a small portion of the total variance in deficiencies could be explained, much work remains to explore factors that influence deficiencies.

Gender disparity in living renal transplant donation

Numerous studies document that women constitute the majority of living kidney donors, but the reasons behind the disparity in donation rates between men and women remain obscure. We studied this issue by gathering data on family members of living donor allograft recipients at a single large center over a 5-year period (n = 144). By considering all potential donors (spouses and first-degree relatives) within each recipient's immediate family, we determined that men and women are excluded as donors at approximately similar rates on the basis of medical condition or known blood group type A, type B, type O incompatibility, and that a greater percentage of acceptable female donors (28.3%) compared with men (20.3%) go on to donate a kidney (P: = 0.027). However, when only first-degree relatives are considered, the difference in donation rate between men and women becomes nonsignificant (26.9% of women versus 22.2% of men; P = 0.229). Among spouses, the gender disparity in donation rate is greater (36% of wives versus 6.5% of husbands who are acceptable donors go on to donate a kidney; P = 0.003). Evidence that economic factors may contribute to the overall gender disparity is also presented. In conclusion, the gender disparity among living kidney donors observed in our population can be largely attributed to an overwhelming predominance of wives among spousal donors. Possible explanations and potential interventions to address underrepresentation of male donors are discussed.

Use of arginine vasopressin in the absence of diabetes insipidus: a case study

This case study details the use of arginine vasopressin in a pediatric organ donor. Although arginine vasopressin is primarily administered for its antidiuretic effects in the treatment of diabetes insipidus, the study demonstrates the often overlooked vasoactive effect of arginine vasopressin and its use in a patient without diabetes insipidus.

Pediatric transseptal transsphenoidal pituitary surgery

The use of the transseptal transsphenoidal approach to the pituitary gland has gained acceptance as a safe, relatively atraumatic means of removing pituitary tumors. The outcome in adult patients has been successful; however, the outcome in pediatric patients whose noses may still be developing is not well described. We reviewed the outcomes in 41 patients younger than age 18 years who underwent transseptal transsphenoidal pituitary surgery at our institution between 1986 and 1997 (20 boys and 21 girls; age, 3 to 17 years; mean age, 13.4 years). The most common diagnosis was prolactin-secreting adenoma (14 patients), followed by craniopharyngioma (7 patients). Presenting symptoms included headache (20 patients), galactorrhea (13 patients), and menstrual irregularities (11 patients). The most common early complication was transient diabetes insipidus (20 patients). No patient experienced serious bleeding at pack removal and no patient developed a cerebrospinal fluid leak postoperatively. Follow-up ranged from 3 months to 12.7 years, with 7 patients experiencing recurrent or residual disease between 6 days and 2 years after their original transseptal procedure. The most common long-term surgical complication was nasal obstruction in 5 patients, 3 of whom also complained of seasonal allergies. Four patients complained of recurrent sinus infections, and 4 patients noted an external nasal deformity as a result of the surgery.

Impaired bone formation in transgenic mice resulting from altered integrin function in osteoblasts

To determine the role of integrins in mature osteoblasts in vivo, we expressed in transgenic mice a dominant-negative integrin subunit (beta1-DN) consisting of the beta1 subunit cytoplasmic and transmembrane domains, driven by the osteoblast-specific osteocalcin promoter. Immature osteoblasts isolated from transgenic animals differentiated normally in vitro until the osteocalcin promoter became active; thereafter they detached from the substratum, suggesting that beta1-DN was impairing adhesion in mature osteoblasts. Transgenic animals had reduced bone mass, with increased cortical porosity in long bones and thinner flat bones in the skull. At 35 days, the rate of bone formation was reduced in cortical bone, and the parietal bones were 45% thinner than in wild-type animals. Active osteoblasts were less polar and had larger areas of cytoplasm with intracellular stores of matrix molecules. Osteocyte lacunae appeared normal around the cell body but did not have normal canilicular structures. At 90 days, the parietal bone of transgenic males was of normal width, suggesting that the original defect in matrix deposition had been repaired or compensated for. In contrast, transgenic females still had decreased bone mass in the parietal bone at 90 days. The decreased bone mass in TG females was accompanied by increased staining for osteoclast activity, suggesting that there was a sex-specific defect in mature animals.

Loss of hypoglycemia awareness in an adolescent with type 1 diabetes mellitus during treatment with fluoxetine hydrochloride

A 17-year-old boy with type 1 diabetes mellitus developed new loss of hypoglycemia awareness while being treated with fluoxetine hydrochloride for depression. Hypoglycemia unawareness resolved after this medication was discontinued.

Experts recommend minimum nurse staffing standards for nursing facilities in the United States

The experts concluded that current data show that the average nurse staffing levels (for RNs, LVN/LPNs, and NAs) in nursing homes are too low in some facilities to provide high quality of care. Caregiving, the central feature of a nursing home, needs to be improved to ensure high quality of care to residents. Because detailed time studies have not been conducted on the amount of time that is required to provide high quality of care to residents, expert opinion is currently the best approach to addressing the problem of inadequate staffing. Increases in the education level and training of nursing staff are also strongly recommended as a step to improving quality of care and reducing turnover rates in nursing homes. These recommendations are designed for consideration by Congress, HCFA regulators, policymakers, nursing home administrators, and nurses. Ideally, Congress would pass legislation establishing these recommendations as minimum standards for all nursing homes or direct HCFA to establish detailed minimum nurse staffing standards to ensure that staffing levels take into account the number and the case-mix of the residents. Alternatively, HCFA could introduce minimum staffing standards through the regulatory process. In 1999 there were a number of efforts at the state level to increase minimum staffing levels. Mohler (1999) surveyed selected states and found that 21 states had either proposed new legislation or were considering proposals for new legislation or new regulations. In California, for example, in 1999 the state budget approved $31 million in new state funds (to be matched with $31 million in federal Medicaid dollars) to increase nursing home staffing minimum requirements from 2.8 to 3.2 hr per resident day and to increase wage rates. Overall, nursing facilities need to be held accountable by HCFA for providing adequate levels and types of staffing to meet the needs of their residents, especially because government is paying for 61% of the expenditures. Adopting these minimum standards will have an important impact on improving the quality of the nation's nursing home care. Additional research is needed to determine appropriate levels and types of staff to provide high quality of care to residents. These studies could test the proposed staffing standards against existing staffing levels to examine the impacts on quality. As new data become available on staffing levels, revisions of staffing standards should be made if necessary to ensure that high standards are maintained.

MMDB: 3D structure data in Entrez

Three-dimensional structures are now known for roughly half of all protein families. It is thus quite likely, in searching sequence databases, that one will encounter a homolog with known structure and be able to use this information to infer structure-function properties. The goal of Entrez's 3D structure database is to make this information accessible and useful to molecular biologists. To this end, Entrez's search engine provides three powerful features: (i) Links between databases; one may search by term matching in Medline((R)), for example, and link to 3D structures reported in these articles. (ii) Sequence and structure neighbors; one may select all sequences similar to one of interest, for example, and link to any known 3D structures. (iii) Sequence and structure visualization; identifying a homolog with known structure, one may view a combined molecular-graphic and alignment display, to infer approximate 3D structure. Entrez's MMDB (Molecular Modeling DataBase) may be accessed at: http://www.ncbi.nlm.nih.gov/Entrez/structure.html

Continuous veno-venous haemodialysis with a novel bicarbonate dialysis solution: prospective cross-over comparison with a lactate buffered solution

OBJECTIVE

To compare acid-base balance, lactate concentration and haemodynamic parameters during continuous veno-venous haemodialysis (CVVHD) using bicarbonate or a lactate buffered dialysate.

METHODS

DESIGN

prospective randomized cross-over design;

SETTING

Multicentre combined adult surgical and medical intensive care units. Patients; 26 critically ill patients starting CVVHD for acute renal failure.

INTERVENTIONS

Each patient to receive 48 h of bicarbonate dialysate and 48 h of lactate dialysate with the order of the 48 h block randomized at trial entry.

RESULTS

The serum bicarbonate increased from baseline in both the lactate and bicarbonate groups over the first 48 h of treatment (16.3+/-1.53 to 22.2+/-1.41 mmol/l and 18.9+/-2.02 to 22.2+/-1.18 mmol/l, respectively) and continued to rise towards normal over the next 48 h after cross-over to the other dialysate. The H+ and pCO2 only trended higher in the lactate group. Unlike the acid base parameters, serum lactate levels varied depending on the dialysate composition. The patients initially randomized to the lactate dialysate had higher serum lactate levels and these tended to increase further after 48 h of dialysis from 2.4+/-0.8 to 2.6+/-0.4 mmol/l. However, in the following 48 h the lactate levels fell to 1.8+/-0.6 (P = 0.039) while patients were being treated with the bicarbonate dialysate. Similar results were seen in the patients initially randomized to the bicarbonate dialysate. Serum lactate remained stable over the first 48h (1.4+/-0.2 to 1.5+/-0.1 mmol/l) but after cross-over to the lactate dialysate increased to 3.1+/-0.7 mmol/l (P = 0.051). Overall, lactate levels were significantly higher during dialysis with lactate buffered solution than bicarbonate buffered solution (2.92+/-0.45 vs. 1.61+/-0.25 mmol/l P = 0.01). Mean arterial pressure trended higher during bicarbonate dialysis but did not reach statistical significance (lactate vs. bicarbonate; 71.1+/-3.1 vs. 81.3+/-5.8 mm Hg). Subgroup analysis of the patients with abnormal liver indices or increased lactate levels at initiation of dialysis (n = 15) revealed only a trend toward better bicarbonate control (lactate vs. bicarbonate; 22.00+/-1.73 vs. 22.86+/-1.09, P = 0.2). However, in this group with hepatic insufficiency elevations in serum lactate were even greater during lactate compared to the bicarbonate dialysis (3.39+/-0.68 vs. 1.78+/-0.42 P = 0.036). Patients who had elevations of lactate during lactate dialysis had a high mortality (6 of 7). These patients had an even greater disparity in lactate levels (4.3+/-1.4 vs. 1.3 +/-0.3) and blood pressure (68.0+/- 7.7 vs. 87.2+/-17.1) between lactate and bicarbonate dialysis. Due to small patient numbers these comparisons did not achieve statistical significance.

CONCLUSION

During continuous veno venous haemodialysis a bicarbonate buffered dialysis solution provided equal acid-base control but maintained more normal lactate levels than a lactate buffered dialysis solution.

Fetal and neonatal hyperthyroidism

Fetal and neonatal hyperthyroidism are usually produced by transplacental passage of thyroid-stimulating immunoglobulins. Most commonly, the thyroid-stimulating immunoglobulins are a component of active maternal Graves' disease. However, such antibodies may continue to be produced after ablation of the thyroid by surgery, radioiodine, or by the immune mechanisms of Hashimoto's thyroiditis. Other mechanisms that have produced fetal and neonatal hyperthyroidism include activating mutations of the stimulatory G protein in McCune-Albright syndrome and activating mutations of the thyrotropin (TSH) receptor. Fetal hyperthyroidism may be associated with intrauterine growth retardation, nonimmune fetal hydrops, craniosynostosis, and intrauterine death. Features of this condition in the neonate include hyperkinesis, diarrhea, poor weight gain, vomiting, ophthalmopathy, cardiac failure and arrhythmias, systemic and pulmonary hypertension, hepatosplenomegaly, jaundice, hyperviscosity syndrome, thrombocytopenia, and craniosynostosis. The time course of thyrotoxicosis depends on etiology. Remission by 20 weeks is most common in neonatal Graves' disease; remission by 48 weeks is nearly always seen. A subset of these patients may have persistent disease when there is a strong family history of Graves' diseases. Disease persistence is characteristic of patients with activating mutations of the TSH receptor. Treatment of fetal hyperthyroidism comprises administration of antithyroid drugs to the mother. Fetal heart rate and fetal growth should be monitored. Ultrasonography may reveal changes in thyroid size. At times, cordocentesis may be useful for monitoring fetal thyroid function. Hyperthyroid neonates may be treated with antithyroid drugs, beta-adrenergic receptor blocking agents, iodine, or iodinated contrast agents, and at times, with glucocorticoids and digoxin. Nonremitting causes of neonatal hyperthyroidism require ablative treatments such as thyroidectomy.

Adrenal suppression secondary to inhaled fluticasone propionate

BACKGROUND

Inhaled glucocorticoids are the medical treatment of choice in many of patients with asthma. Fluticasone propionate is an inhaled glucocorticoid with little systemic bioavailability via the oral route and infrequent association with systemic adverse effects at the recommended dosage.

OBJECTIVE

To report a case of adrenal suppression and exogenous glucocorticoid excess from inhaled fluticasone propionate.

METHODS

A 9-year-old girl with a previous history of episodic asthma was placed on 550 microg of fluticasone propionate daily for severe labile asthma diagnosed by history and methacholine challenge. The patient returned 6 months later with complaints of increased appetite, nausea, and feeling "hot and flushed." On physical exam she had stigmata of Cushing's syndrome. The patient subsequently developed orthostatic hypotension and moderate dehydration following a viral illness. After a long taper of fluticasone propionate the patient' s adrenal function returned to normal and she had no acute or chronic exacerbations of her asthma.

RESULTS

Her 8 AM cortisol was undetectable with an ACTH of 21 pg/mL. The serum prolactin, TSH, free thyroxine, insulin-like growth factor I, and renin activity were all normal. An MRI study of her head was also normal. Repeat methacholine challenges while receiving a much smaller dose fluticasone propionate showed a significant decrease in airway reactivity.

CONCLUSION

Adrenal suppression can occur from inhaled fluticasone propionate at a dosage less than has been previously reported.

Structural-functional bioinformatics: knowledge-based NMR interpretation

This paper describes a knowledge-based approach to a problem of structural-functional bioinformatics, specifically the determination of protein structure through the automated analysis of NMR data. Highly successful results in carrying out sequence-specific assignments of residues from multidimensional NMR datasets has led us to automation of NOE dataset interpretation and a design for integrating these results with other protein structure and function analysis programs.

Immunization with a LEAPS heteroconjugate containing a CTL epitope and a peptide from beta-2-microglobulin elicits a protective and DTH response to herpes simplex virus type 1

A ligand epitope antigen presentation system (LEAPS) heteroconjugate vaccine containing a CTL epitope (H1) from the HSV-1 immediate early protein ICP27 (322-332) and a peptide sequence (J) from beta-2-microglobulin (35-50) elicited protection from intraperitoneal viral challenge and promoted DTH responses. The H1 peptide and other H1 containing heteroconjugates did not elicit protection or DTH responses. Antibody to the H1 peptide could not be detected by ELISA following vaccination with peptide, heteroconjugate or natural infection. The LEAPS heteroconjugate appears to prime a Thl-like response which is subsequently boosted by infection. These studies show that attachment of the J peptide can make a CTL epitope into a vaccine which is immunogenic and promotes a protective Th1 type of response.

Bisphosphonates for treatment of childhood hypercalcemia

Most clinicians only have a limited experience in treating childhood hypercalcemia with bisphosphonates. We report our experience in the use of intravenous and oral bisphosphonates in a 5-year-old with hypercalcemia secondary to acute lymphocytic leukemia, a 16-year-old with immobilization hypercalcemia, and a 14-year-old with chronic hypercalcemia of unknown cause. Single infusions of 0.5 mg/kg and 1 mg/kg of intravenous pamidronate were administered over 4 hours. No adverse reactions were observed except for hypocalcemia. A dose between 10 and 20 mg of oral alendronate was successfully used to maintain normocalcemia in the patient with chronic hypercalcemia. In our experience, the administration of bisphosphonates has enabled us to achieve normocalcemia in all cases, and in all cases there were no significant side effects. Long-term potential side effects from their use in children during the active phase of growth remain unknown.

Thyrotoxicosis in children

Graves' disease is the predominant cause of hyperthyroidism in the pediatric age group. Other disorders must be recognized, however, because adequate management relies on a precise diagnosis. Careful monitoring of the thyroid status is required during this active phase of growth and development.