Loss of wild-type MEN1 gene expression in multiple endocrine neoplasia type 1-associated parathyroid adenoma

Multiple endocrine neoplasia type 1 (MEN1) is a human hereditary tumor syndrome characterized by the development of endocrine adenomas of the parathyroid, anterior pituitary, and enteropancreatic tissue. Several lines of evidence have implicated the recently identified MEN1 gene located on chromosome 11q13 as a recessive tumor suppressor gene. Here, we analyzed MEN1 wild-type gene expression in tumors from a large MEN1 kindred. A deletion of codons 227-228 (678del6) located in exon 4 was found in tumor and peripheral blood complementary DNA using a simplified single-strand conformational polymorphism (SSCP) approach well suited for clinical MEN1 mutation screening. The identified 678del6 cDNA mutation deletes a potential phosphorylation site (Tyr227) and corresponds to a germ line mutation co-segregating with disease phenotype in this MEN1 family. Loss of heterozygosity analysis by fluorescent microsatellite PCR showed an exclusive loss of the MEN1 wild-type (and retention of the mutated) allele detectable in DNA from microdissected parathyroid and pancreatic, but not in adrenal, adenomas. Our findings confirm the synergism between MEN1 gene mutations and subsequent MEN1 allelic losses in the tumorigenesis of MEN1-associated adenomas.

Cardiac troponin I as a predictor of major cardiac events in emergency department patients with acute chest pain

OBJECTIVES

We sought to evaluate the diagnostic and prognostic value of cardiac troponin I (cTnI) in emergency department (ED) patients with chest pain.

BACKGROUND

Although cTnI has been shown to correlate with an increased risk for complications in patients with unstable angina, the prognostic significance of this assay in the heterogeneous population of patients who present to the ED with chest pain is unclear.

METHODS

cTnI and creatine kinase-MB fraction (CK-MB) mass concentration were collected serially during the first 48 h from onset of symptoms in 1,047 patients > or =30 years old admitted for acute chest pain. Sensitivity, specificity and receiver operating characteristic curves were calculated for cTnI and CK-MB collected in the first 24 h.

RESULTS

The sensitivity, specificity and positive predictive value of cTnI for major cardiac events were 47%, 80% and 19%, respectively. Among patients were who ruled out for myocardial infarction, cTnI was elevated in 26% who had major cardiac complications compared with 5% for CK-MB; the positive predictive value for an abnormal cTnI result was 8%. Elevated cTnI in the presence of ischemia on the electrocardiogram was associated with an adjusted odds ratio of 1.8 (95% confidence interval 1.1 to 2.9) for major cardiac events within 72 h. Among patients without a myocardial infarction or unstable angina, cTnI was not an independent correlate of complications.

CONCLUSIONS

In patients presenting to the ED with acute chest pain, cTnI was an independent predictor of major cardiac events, However, the positive predictive value of an abnormal assay result was not high in this heterogeneous cohort.

Menin mutations in the diagnosis and prediction of multiple endocrine neoplasia type 1

INTRODUCTION

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the development of multiple endocrine adenomas, typically in the pancreas, anterior pituitary, and parathyroid glands. The disease is associated with germ-line mutations of the menin gene, a putative tumor-suppressor gene located on human chromosome 11q13.

METHODS

To facilitate the diagnosis and prediction of MEN1 in patients and their relatives, we developed a molecular two-step strategy to screen for menin gene mutations. DNA fragments covering the entire menin coding sequence are generated from patient cDNA by polymerase reaction (PCR) and subsequently analyzed by single-strand conformational polymorphism electrophoresis (SSCP). Fragments with aberrant SSCP migration are DNA-sequenced to directly characterize menin mutations. In a second diagnostic step, genomic DNA of healthy relatives of the corresponding MEN1 index patient is analyzed by PCR, with only the specific exon amplified harboring the family-specific mutation. Mutation-specific restriction enzyme digestion of this PCR product finally allows the identification of mutation carriers through pathological restriction fragment patterns.

RESULTS

Using this approach, we identified an in-frame deletion mutation (delta Tyr Met) located in menin exon 4 (codon 227-228) that co-segregates with the disease phenotype in a large MEN1 family from Southern Germany.

CONCLUSION

It is likely that the direct molecular analysis of menin gene mutations will replace the genetic and biochemical screening tests currently used in the clinical management of MEN1 families. In addition, these studies may provide clues to the tumor biology of both sporadic and MEN1-associated endocrine adenomas.

Body mass index as a correlate of postoperative complications and resource utilization

PURPOSE

To describe the relationship of body mass index (BMI) with postoperative complications and resource utilization.

PATIENTS AND METHODS

Two thousand nine hundred and sixty-four patients 50 years or older undergoing elective noncardiac surgery with an expected length of stay > or = 2 days were enrolled in a prospective cohort study to measure major cardiac complications, noncardiac complications, length of stay, and costs. The setting was an urban teaching hospital. A preoperative history, physical, electrocardiogram (ECG), and chart review were performed by study personnel. Postoperative complications were detected by ECGs, creatine kinase and creatine kinase MB levels, and daily chart review. Total costs were obtained from the hospital's computerized database.

RESULTS

Complication rates were not different among BMI groups (underweight < 20, normal 20 to 29, overweight 30 to 34, most overweight > 34), but patients with BMI 30 to 34 and > 34 who underwent abdominal or gynecologic procedures had significantly higher wound infection rates (11% each) than normal weight patients (4.7%) or the underweight (0%). After adjusting for age, race, gender, smoking history, comorbid diseases, procedure type, and insurance status, there were nonsignificant trends toward increased resource utilization by the most overweight patients (BMI > 34). These patients stayed 0.8 days longer (P = 0.13) and had total costs that were $843 higher (P = 0.17) than patients of normal weight (BMI 20 to 29). The underweight patients stayed 0.9 days longer (P = 0.23) and had total costs that were $3,150 higher (P = 0.04) than patients of normal weight. Quadratic models to test for a U-shaped relationship found no correlation between BMI and length of stay, but did find that BMI was significantly correlated with total costs (P = 0.04). This relationship persisted when patients who had complications were excluded from the analysis.

CONCLUSIONS

Overall, BMI was not significantly correlated with postoperative complications or length of stay. However, overweight patients who underwent abdominal or gynecologic procedures had higher wound infection rates, and patients with the highest and lowest BMIs had significantly higher adjusted total costs.

[Ovarian angioma. Report of 3 asymptomatic cases]

In 3 female patients, aged 46, 50 and 74 years respectively, ovarian angiomas measuring 3, 5 and 30 mm in diameter were discovered. All the angiomas were asymptomatic. They were either associated with endometrioid carcinoma or uterine leiomyomas, or detected casually by ultrasound scan in a patient with ascites, intrahepatic nodule and increased serologic CA 125. The immunohistochemical studies failed to reveal any affinity between the vascular endothelium of our ovarian angiomas and oestrogen and progesterone receptors.

RAG mutations in human B cell-negative SCID

Patients with human severe combined immunodeficiency (SCID) can be divided into those with B lymphocytes (B+ SCID) and those without (B- SCID). Although several genetic causes are known for B+ SCID, the etiology of B- SCID has not been defined. Six of 14 B- SCID patients tested were found to carry a mutation of the recombinase activating gene 1 (RAG-1), RAG-2, or both. This mutation resulted in a functional inability to form antigen receptors through genetic recombination and links a defect in one of the site-specific recombination systems to a human disease.

Health sciences library building projects: 1995 survey

The Medical Library Association's fifth annual survey of recent health sciences library building projects identified twenty-five libraries planning, expanding, or constructing new library facilities. None of the fifteen new library projects are free standing structures; however, several occupy a major portion of the project space. Ten projects involve renovation of or addition to existing space. Information regarding size, cost of project, type of construction, completion date, and other factual data was provided for twelve projects. The remaining identified projects are in pre-design or early-design stages, or are awaiting funding approval. Library building projects for three hospital libraries, three academic medical libraries, and an association library are described. Each illustrates how considerations of economics and technology are changing the traditional library model from a centrally stored information depository housing a wide range of information under one roof where users come to the information, into an electronic model gradually shifting from investment in the physical presence of resources to investment in creating work space for creditible information specialists who help in-house and distanced users to obtain information electronically from any place and at any time. This new model includes a highly skilled library team to manage, filter, and package the information to users trained by these resident experts.

Noninvasive positive-pressure ventilation in acute respiratory distress without prior chronic respiratory failure

We evaluated the efficacy of noninvasive mechanical ventilation (NIMV) in alleviating distress and avoiding intubation in patients with de novo acute respiratory failure complicating primary medical disorders. Eleven consecutive patients with severe respiratory distress were entered. In all patients a decision to intubate on an urgent basis had been made, but NIMV could be initiated within minutes. The patients suffered from acute pulmonary edema (five), sepsis/ARDS (two), status asthmaticus (two), and severe pneumonia (two). Dyspnea score (max=10) was (+/- SD) 8.4 +.- 1.6, scale for accessory muscle use (max=5) was 4.2 +/- 0.7, and respiratory rate was 37.6 +/- 3.8 min -1. Pa CO2, pH, and base excess (BE) were 48 +/- 18 mm Hg, 7.27 +/- 0.13, and -5.5 +/- 7.4, respectively, with five patients showing severe metabolic acidosis (BE < - 10). NIMV was applied using proportional assist ventilation. There were three early failures. These included the two patients with sepsis/ARDS who did not tolerate the mask. One patient failed because Pa CO2 and pH deteriorated despite subjective improvement. The remaining eight patients demonstrated progressive improvement, and none required intubation. The duration of NIMV was 3 h to 2 d. We conclude that when NIMV is made available on a "few minutes" basis, selected patients with severe de novo respiratory distress/failure caused by reversible medical disorders, who would otherwise have been intubated, can be given substantial relief and be spared intubation.

A randomized, double-blind comparison of methoxamine and epinephrine in human cardiopulmonary arrest

The beneficial effect of epinephrine has been attributed to its alpha-adrenergic properties. The present study was designed to compare the effects of epinephrine and methoxamine in witnessed cardiac arrests. Consecutive, witnessed cardiac-arrest victims presenting to the emergency room or from the inpatient population of our institution were enrolled in this study. Patients were randomized to receive either epinephrine (2 mg bolus followed by 2 mg every 4 min) or methoxamine (40 mg bolus followed after 4 min by 40 mg) in a blind design. Patients were followed prospectively for survival and neurologic outcome. A total of 199 patients were randomized into the study, but 54 had to be retrospectively dropped from analysis for failure to comply with the study protocol. Of the 145 patients remaining, 77 received methoxamine (M) and 68 epinephrine (E). There was no difference in rate of successful resuscitation (42% versus 53%, M versus E, respectively), or in neurologic outcome as measured by the Glasgow-Pittsburgh Coma Score (GPCS). This study failed to demonstrate any difference in the rate of initial resuscitation, survival to discharge from the hospital, or neurologic status with methoxamine as opposed to epinephrine in the setting of cardiac arrest.

Exon trap analysis of a NF1 splice-site mutation in a chronic myelomonocytic leukemia patient

We have previously described a patient with chronic myelomonocytic leukemia who exhibited a mutation (del-10:-8) in the splice-acceptor region in front of the FLR exon of the NF1 tumor suppressor gene. In order to evaluate whether this mutation indeed affects correct splicing of this exon we used an exon trap approach. Our data unequivocally prove the functional relevance of this NF1 mutation. Exon trapping thus represents an attractive strategy to study the consequences of putative splice-site mutations if RNA samples are not available.

Health sciences library building projects: 1994 survey

Designing and building new or renovated space is time consuming and requires politically sensitive discussions concerning a number of both long-term and immediate planning issues. The Medical Library Association's fourth annual survey of library building projects identified ten health sciences libraries that are planning, expanding, or constructing new facilities. Two projects are in predesign stages, four represent new construction, and four involve renovations to existing libraries. The Texas Medical Association Library, the King Faisal Specialist Hospital and Research Centre Library, and the Northwestern University Galter Health Sciences Library illustrate how these libraries are being designed for the future and take into account areas of change produced by new information technologies, curricular trends, and new ways to deliver library services.

Relief of posttraumatic headache by intravenous chlorpromazine

We report the case of an 18-year-old male with a vascular-type headache occurring 3 days after a minor closed-head injury. The headache resolved completely, without recurrence, with a single dose of intravenous chlorpromazine. This case and the few others reported in the literature illustrate that the response of a headache to antimigraine therapy cannot be relied upon to diagnose or confirm a diagnosis of migraine headache, or to rule out other intracranial pathology.

Analysis of p53 mutations in a large series of lymphoid hematologic malignancies of childhood

p53 mutations are found in a wide variety of cancers, including hematologic malignancies. These alterations apparently contribute to development of the malignant phenotype. We analyzed a large series of lymphoid (330 cases) and a smaller series of myeloid (29 cases) malignancies of childhood for p53 mutations by single-strand conformational polymorphism (SSCP) following polymerase chain reaction. Samples with abnormal SSCP were reamplified and analyzed by direct sequencing method. p53 mutations were detected within the known mutational hotspots (exons 5 to 8) in 8 of 330 lymphoid malignancies, and in none of 29 myeloid malignancies, showing that the frequency of p53 mutations in childhood lymphoid malignancies was very low (8 of 330 cases [2%]). Four of these patients had very aggressive, fatal acute lymphocytic leukemia (ALL). None of 13 infants and none of 48 patients with T-lineage leukemia had detectable p53 mutations in their ALL cells. Exceptionally, p53 mutations were comparatively frequent in a small sample of B-cell non-Hodgkin's lymphomas (2 of 8 cases). Mutations were detected in samples from two patients with ALL at relapse; these were not detected in samples at initial diagnosis from the same patients, suggesting that p53 mutations may be associated with progression to a more malignant phenotype. Seven of eight alterations of p53 were missense mutations, and seven of eight samples may be heterozygous for the mutant p53, indicating that p53 protein may act in a dominant negative fashion.

Recent health sciences library building projects

The Medical Library Association's third annual survey of recent health sciences library building projects identified fourteen libraries planning, expanding, or constructing new library facilities. Three of five new library buildings are freestanding structures where the library occupies all or a major portion of the space. The two other new facilities are for separately administered units where the library is a major tenant. Nine projects involve additions to or renovations of existing space. Six projects are in projected, predesign, or design stages or are awaiting funding approval. This paper describes four projects that illustrate technology's growing effect on librarians and libraries. They are designed to accommodate change, a plethora of electronic gear, and easy use of technology. Outwardly, they do not look much different than many other modern buildings. But, inside, the changes have been dramatic although they have evolved slowly as the building structure has been adapted to new conditions.

Mutations within the FLR exon of NF1 are rare in myelodysplastic syndromes and acute myelocytic leukemias

A mutational hotspot in the neurofibromatosis 1 (NF1) gene has recently emerged from the analysis of different malignancies including one patient with myelodysplastic syndrome (MDS). In these cases, Lys 1423 in the GTPase-activating protein (GAP)-related domain of NF1 is substituted which causes a significant reduction of intrinsic GAP activity. We studied 57 MDS patients and 27 cases of acute myelocytic leukemia (AML) for mutations at codon 1423 in the so-called FLR exon of NF1 by an assay based on restriction enzyme digestion. We investigated the entire FLR exon and its flanking intron sequences using single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR) products and sequencing. None of the cases exhibited a codon 1423 mutation. However, a patient with chronic myelomonocytic leukemia (CMML) showed a 3 bp deletion within the splice acceptor region in front of the FLR exon. These data suggest that NF1 exon FLR mutations contribute infrequently to the development of MDS and AML.

P53 mutations in myelodysplastic syndromes

Point mutations in the p53 tumor-suppressor gene are the most frequently identified genetic alterations in human malignancies. In order to evaluate the role of p53 mutations in the multistep process of leukemogenesis we studied 61 patients with myelodysplastic syndromes using single-strand conformation polymorphism analysis of polymerase chain reaction products as well as direct sequencing. Mutant alleles were observed in 1/14 refractory anemia with excess of blasts (RAEB) and 2/5 RAEB in transformation. The three mutations represented G:C to A:T transitions at codon 141 (exon 5) and codons 245 and 248 (exon 7), respectively. These data suggest that p53 mutations may contribute, albeit rarely, to the development of preleukemic disorders of the myeloid cell lineage.

Controlled trial of Giardia lamblia: control strategies in day care centers

BACKGROUND

Strategies for control of Giardia lamblia in day care differ in numbers of children treated and in costs to parents and day care operators. The effectiveness of these strategies has not been systematically evaluated.

METHODS

We conducted a prospective randomized controlled trial comparing three strategies for control of Giardia in infant-toddler day care centers: Group 1, exclusion and treatment of symptomatic and asymptomatic infected children; Group 2, exclusion and treatment of symptomatic infection only; Group 3, exclusion and treatment of symptomatic infection, treatment of asymptomatic infection in the center. The study included 31 day care centers with 4180 child-months of observation. Giardia prevalence was determined before intervention and 1, 2, 4, and 6 months later; new infants and toddlers were tested on admission.

RESULTS

Initial Giardia prevalences were 18% to 22% in the three groups. Giardia was identified in 10.5% of 676 new infants and toddlers entering study day care centers during the 6-month follow-up. Giardia prevalences by intervention group were 8%, 12%, and 7% at 1 month, and 7%, 8%, and 8% at 6 months.

CONCLUSIONS

The stricter intervention resulted in greater cost in terms of child day care and parents' work days lost, but did not result in significantly better control of Giardia infections in this day care environment.

User attitudes toward end-user literature searching

A survey to determine attitudes toward end-user searching was made at Loyola University's Medical Center Library using MEDIS, an online full-text and bibliographic medical retrieval system. One hundred forty-one completed questionnaires were analyzed for this report. Information was collected on user familiarity with computers, end-user training, system use, mechanics of searching, and attitudes toward future use. Computer familiarity was highest among the faculty users. Ninety percent of the respondents saw librarians as a crucial agent in training and in providing end-user assistance. Respondents identified five major reasons for using the system: helpfulness, convenience, time savings, rapid feedback, and presentation of needed information. Searching the MEDLINE database rather than the full-text database was the search method of choice. Continued use of both mediated and end-user searching was intended by most of the respondents. Survey results support a perceived need for end-user searching and confirmed recommendations of the Association of American Medical Colleges on medical information science skills.

Central and autonomic nervous system side effects of ketanserin

A placebo controlled, randomized, double-blind cross-over study was carried out in 7 healthy volunteers in order to study the central and autonomic nervous system side effects of ketanserin in comparison to clonidine. Psychometric performance was assessed as well as electroencephalographic recordings (EEG), saliva production, mean arterial blood pressure (MAP) and pulse rate under placebo conditions (P, 10 ml saline), following 0.15 mg/kg ketanserin or 2 micrograms/kg clonidine i.v. administration. The sedation index as well as the deceleration of EEG frequencies clearly expressed sedation following both, ketanserin and clonidine. Saliva production was significantly decreased by ketanserin (p less than 0.05) and clonidine (p less than 0.01), respectively. MAP was only very slightly reduced by ketanserin, while clonidine caused a small but significant decrease (p less than 0.0001). The pulse rate changes did not reach a clinically important extent. Thus, sedation as main central nervous system side effect and reduction in salivation as autonomic nervous system side effect of ketanserin could be clearly quantified in comparison to placebo and clonidine.

Vascularized fibular epiphyseal transfer. A clinical study

In a review of the experimental and clinical literature on nonvascularized and vascularized epiphyseal transfer, experience with eight patients with free vascularized fibular epiphyseal transfer suggests that transfer of bone with an open epiphysis offers some potential for growth in either congenital abnormalities or epiphyseal arrest secondary to trauma and infection. In four cases, premature epiphyseal closure prevented appreciable growth. In the other four, the epiphyses remain open and the transferred bones continue to grow. Although the procedure is experimental, the results of combined epiphyseal and metaphyseal vessel transfer with a skin island as a monitor of viability, warrant further investigation.

Pharmacodynamic interaction between midazolam and a specific benzodiazepine antagonist in humans

The pharmacodynamic interaction between midazolam and the specific benzodiazepine antagonist Ro 15-1788 has been investigated in six healthy male volunteers. Hypnotic steady-state concentrations of midazolam (55 +/- 11 ng/mL; mean +/- SD) have been achieved rapidly by an intravenous bolus of 0.07 mg/kg and maintained by an individual but constant infusion rate of 0.025 to 0.04 mg/kg/hr for eight hours. Following a two-hour control period, the antagonist (2.5 mg) or the solvent were injected double-blind in random order. Three hours later, the other medication was administered. Whereas plasma levels of midazolam remained constant throughout the complete eight-hour trial (Clearance = 670 +/- 96 mL/min) concentrations of Ro 15-1788 declined rapidly with an elimination half-life between 0.7 and 1.8 hours and a total plasma clearance of 702 +/- 235 mL/min. Concentrations of Ro 15-1788 approached the analytic limit of 2 ng/mL within three hours. The pharmacodynamic response to midazolam and the antagonist was assessed by a sedation index using visual analogue scales, reaction time (RT) measurements, and transformed Fourier analysis of the power spectrum of the recorded electroencephalogram (EEG). About 30 to 45 seconds following the injection of Ro 15-1788, hypnotic action of midazolam was completely reversed as visualized by return to alpha rhythm in the EEG, shortening of prolonged RT, and normalization of the elevated sedation index. The antagonistic action lasted for about two to three hours. The abrupt arousal from sleep was not associated with any unpleasant sensations, however, three subjects experienced a profound perspiration for about ten minutes following the injection of Ro 15-1788.(ABSTRACT TRUNCATED AT 250 WORDS)