Specificity, sensitivity, and predictive value of apolipoprotein-E genotyping for sporadic Alzheimer's disease

BACKGROUND

We aimed to determine the specificity, sensitivity, and predictive value of apolipoprotein E (APOE) genotyping in 67 consecutive patients with clinical diagnoses of sporadic Alzheimer's disease (AD) who underwent necropsy.

METHODS

We studied patients who attended the Duke Memory Disorders Clinic and were diagnosed as having probable AD. These patients were followed up until they died. APOE genotyping was done during life in most cases, but in some brain tissue obtained at necropsy was used. Members of known AD families were excluded.

FINDINGS

After neuropathological examination 57 (85%) of 67 of our patients were confirmed as having AD including all 43 who had at least one APOE-epsilon 4 allele. None of the patients found not to have AD carried an epsilon 4 allele. In this series, the specificity of the epsilon 4 allele was 100%, the sensitivity 75%, the positive predictive value 100%, and the negative predictive value 42%. In this necropsy-confirmed series, the epsilon 4/epsilon 4 genotype predicted AD with 100% accuracy. The epsilon 3/epsilon 4 and epsilon 2/epsilon 4 genotypes were also unexpectedly highly specific for AD.

INTERPRETATION

Data from hundreds of necropsy-confirmed non-AD patients in other longitudinal necropsy series will allow the predictive value of APOE genotypes to be assessed with useful confidence limits.

Screening and treating depressed patients. A comparison of two controlled citalopram trials across treatment settings: hospitalized patients vs. patients treated by their family doctors. Danish University Antidepressant Group

This study is a comparison across treatment settings of two previously published trials, namely the Danish University Antidepressant Group (DUAG) study on citalopram vs. clomipramine in hospitalized patients with major depression, and the Nordic citalopram vs. imipramine study of depressed patients treated by their family doctors. The Hamilton Depression Scale (HAM-D) had the same level of inter-rater reliability and construct validity in the two settings. Using a HAM-D score of 7 or less as the criterion for full two remission, clomipramine was superior to imipramine and citalopram. Using a reduction of the baseline HAM-D score by 50% or more as a response criterion, there were no differences between the three antidepressants after 5 or 6 weeks of treatment. Citalopram showed superior tolerability to the tricyclic antidepressants.

FRAXF in a patient with chromosome 8 duplication

We report on a folate sensitive fragile site at Xq27-28 in a girl with a multiple congenital anomalies and mental retardation syndrome, who also carries a duplication of the long arm of chromosome 8. The fragile site was shown by FISH to be distal to both FRAXA and FRAXE. DNA hybridisation with probe OxF14 showed the amplification of the CGG repeats of locus FRAXF in the patient and in her clinically normal mother.

Cephalometric assessment in obstructive sleep apnea

It is reported that some specific craniofacial characteristics are associated with obstructive sleep apnea syndrome (OSAS). To test this finding, the present study developed and assessed the feasibility of a craniofacial index score (CIS) in differentiating patients with OSAS from habitual snorers. Anthropometric measurements and lateral head radiographs were obtained on 24 male and 4 female patients with OSAS who had physician-diagnosed OSAS (respiratory disturbance index (RDI) >20), and 25 male and 5 female habitual snorers (RDI <20). Thirteen cephalometric and four anthropometric measure- ments were used in a discriminant model to construct the CIS. The model was able to correctly classify 82.1% of the OSAS group and 86.7% of the snoring group. In addition, variables that were related to the soft tissues, hyoid bone to mandibular plane, Body Mass Index, and soft palate length had the highest predictive value. These findings indicate that a CIS constructed from cephalometric and anthropometric measurements can be used to identify subjects with and without OSAS.

Sleep, breathing, and cephalometrics in older children and young adults. Part II -- Response to nasal occlusion

STUDY OBJECTIVES

We postulated that nasal occlusion would provide a challenge enabling us to assess factors predisposing development of sleep apnea in older children/adolescents and young adults. Factors of interest included sex, age, body mass index (BMI), tonsillar hypertrophy, and cephalometric measurements.

DESIGN

Sleep and breathing variables were examined and compared for four groups of subjects between one baseline night and one night of nasal occlusion in a sleep research laboratory.

SUBJECTS

Healthy, normal boys (n=23, mean age=13.3+/-2.1 years), girls (n=22, mean age=13.8+/-1.8 years), men (n=23, mean age=22.2+/-1.5 years), and women (n=24, mean age=22.4+/-1.8 years) were studied.

MEASUREMENTS AND RESULTS

The following sleep and sleep-related breathing measures showed significant increases in all four groups from baseline to occlusion: percentage of stage 1, number of transient arousals, transient arousal index, apnea index, respiratory disturbance index (RDI), and mean apnea length. No significant relationships were found between occlusion-night RDI and tonsillar size, cephalometric variables, or BMI, either singly or in combination.

CONCLUSIONS

Subjects' responses to nasal occlusion varied: most demonstrated a minimal and clinically insignificant increase in RDI; few showed a marked increase in RDI. Significant increases of sleep fragmentation -- even in the absence of frankly disturbed breathing -- indicate that nasal occlusion may secondarily affect waking function if prolonged over a series of nights.

Sleep, breathing, and cephalometrics in older children and young adults. Part I -- Normative values

STUDY OBJECTIVES

Aims were (1) to provide normative values for sleep and sleep-related breathing variables and physical features (cephalometrics, body mass index [BMI], and tonsillar size) in older children/adolescents and young adults, (2) to describe sex and age group differences, and (3) to evaluate relationships between physical features and sleep-related breathing variables.

DESIGN

Standard polysomnographic variables describing sleep and breathing were measured during a single night. Cephalometric measures were obtained from a standing lateral skull radiograph.

SUBJECTS

Normal, healthy boys (n=23; mean age=13.3+/-2.1 years), girls (n=22; mean age =13.8+/-1.8 years), men (n=23; mean age=22.2+/-1.5 years), and women (n=24; mean age=22.4+/-1.8 years) with BMI less than 27 were evaluated.

RESULTS

Sleep variables showed age group and sex differences consistent with published norms. Slow-wave sleep and rapid eye movement (REM) latency declined with age; transient arousals increased with age. Sleep-related breathing variables showed few changes related to age group or sex; small but statistically significant sex differences were found for arterial oxygen saturation nadir (lower in male subjects) and respiration disturbance index in non-REM sleep (greater in male subjects). Differences in cephalometric measures largely reflected normal growth and expected sex differences. No significant relationships between sleep-related breathing variables and physical findings were observed.

CONCLUSIONS

These data provide well-controlled normative values for sleep, breathing, and cephalometrics in a group of normal older children, adolescents, and young adults. The data provide useful reference points for patients of these ages in whom sleep apnea is suspected, particularly since such clinical studies are normally based on first-night polysomnography. Furthermore, these values represent developmentally appropriate grouping of the data.

Controversies in case management

A myriad of controversies exists around the provision of case management services in the private, public, nonprofit or insurance sector. As our population ages, it will be important for all of us to confront these issues as our profession continues to grow and inevitably change. In addition, it will be increasingly important, given the limited resources which will be available, for all sectors to join and work together to ensure that the needs of our older clients are met with services of the highest quality.

Characteristics of subjects with chronic pain, in relation to local and widespread pain report. A prospective study of symptoms, clinical findings and blood tests in subgroups of a geographically defined population

The relation between reported chronic pain and clinical findings was studied by comparing survey data six months before and eighteen months after a clinical examination. Studied individuals (n = 165) were randomly selected from subsamples of an initial survey (n = 1806) to a general population. Among individuals reporting chronic pain 85% were assessed to have chronic pain at the examination. Diagnoses were found in 22% of examined pain individuals. Myofascial pain syndrome and myalgia were the most common findings. Compared with located neck-shoulder pain, widespread pain had a greater impact on the individual, a worse prognosis regarding pain duration and working capacity, and revealed a raised serum urate level of unclear significance. Although no specific cause of pain is found in individuals with widespread pain it is important to identify and treat this group due to the great effects on functional capacity and the worse prognosis.

Alterations of yeast artificial chromosome transgenic sequences in stretched embryonic stem-cell chromatin visualized by fluorescence in situ hybridization

Transgenic mice have been generated from embryonic stem (ES) cells carrying functional genes cloned within yeast artificial chromosomes (YACs). Information on the integrity and organization of the inserted sequences, including the number of copies and their orientation to each other, is still limited by current methods. We have applied fluorescence in situ hybridization to stretched chromatin preparations from YAC-transfected ES cells to analyze the organization and copy number of the integrated sequences.

An STS-based map of the human genome

A physical map has been constructed of the human genome containing 15,086 sequence-tagged sites (STSs), with an average spacing of 199 kilobases. The project involved assembly of a radiation hybrid map of the human genome containing 6193 loci and incorporated a genetic linkage map of the human genome containing 5264 loci. This information was combined with the results of STS-content screening of 10,850 loci against a yeast artificial chromosome library to produce an integrated map, anchored by the radiation hybrid and genetic maps. The map provides radiation hybrid coverage of 99 percent and physical coverage of 94 percent of the human genome. The map also represents an early step in an international project to generate a transcript map of the human genome, with more than 3235 expressed sequences localized. The STSs in the map provide a scaffold for initiating large-scale sequencing of the human genome.

Intron phase correlations and the evolution of the intron/exon structure of genes

Two issues in the evolution of the intron/exon structure of genes are the role of exon shuffling and the origin of introns. Using a large data base of eukaryotic intron-containing genes, we have found that there are correlations between intron phases leading to an excess of symmetric exons and symmetric exon sets. We interpret these excesses as manifestations of exon shuffling and make a conservative estimate that at least 19% of the exons in the data base were involved in exon shuffling, suggesting an important role for exon shuffling in evolution. Furthermore, these excesses of symmetric exons appear also in those regions of eukaryotic genes that are homologous to prokaryotic genes: the ancient conserved regions. This last fact cannot be explained in terms of the insertional theory of introns but rather supports the concept that some of the introns were ancient, the exon theory of genes.

The Rhizobium meliloti region located downstream of the nod box n6 is involved in the specific nodulation of Medicago lupulina

Six nod box regulatory sequences are present in the Rhizobium meliloti genome. We have analysed the DNA region located downstream of nod box n6, and identified three open reading frames, designated nolQa, nolQb and nolS. LacZ fusions in these ORFs are not induced by classical nod gene inducers, which indicates that their expression either is not under the control of the nod box, or involves another regulatory mechanism acting in conjunction with the NodD/nod box regulatory circuit. Mutations in this n6 locus result in a delay in nodule formation on a particular host, Medicago lupulina. As this region is not strictly conserved among different R. meliloti strains, nolQa, nolQb and nolS may constitute auxiliary nodulation genes, for which the selection pressure is limited to particular host plants.

Identification of a supernumerary marker derived from chromosome 17 using FISH

We report on a 15-year-old girl with mental retardation, obesity, short stature and minor anomalies. She had 47 chromosomes with a minute extra ring which was identified by FISH to be derived from chromosome 17.

TRPC1, a human homolog of a Drosophila store-operated channel

In many vertebrate and invertebrate cells, inositol 1,4,5-trisphospate production induces a biphasic Ca2+ signal. Mobilization of Ca2+ from internal stores drives the initial burst. The second phase, referred to as store-operated Ca2+ entry (formerly capacitative Ca2+ entry), occurs when depletion of intracellular Ca2+ pools activates a non-voltage-sensitive plasma membrane Ca2+ conductance. Despite the prevalence of store-operated Ca2+ entry, no vertebrate channel responsible for store-operated Ca2+ entry has been reported. trp (transient receptor potential), a Drosophila gene required in phototransduction, encodes the only known candidate for such a channel throughout phylogeny. In this report, we describe the molecular characterization of a human homolog of trp, TRPC1. TRPC1 (transient receptor potential channel-related protein 1) was 40% identical to Drosophila TRP over most of the protein and lacked the charged residues in the S4 transmembrane region proposed to be required for the voltage sensor in many voltage-gated ion channels. TRPC1 was expressed at the highest levels in the fetal brain and in the adult heart, brain, testis, and ovaries. Evidence is also presented that TRPC1 represents the archetype of a family of related human proteins.

PCDD/PCDF levels in the blood of workers at a pulp and paper mill

Blood samples from 34 workers at a pulp and paper mill and from 14 control persons were analysed for 2,3,7,8-substituted PCDDs and PCDFs. There were no statistically significant differences in total lipid-adjusted PCDD/PCDF concentrations, expressed as toxic equivalents, in blood plasma between the potentially exposed bleaching plant or paper mill workers and the controls. The mean level was 61 pg/g I-TEQ in bleaching plant workers, 60 pg/g I-TEQ in paper mill workers and 49 I-TEQ pg/g in controls. Regarding the concentrations of individual isomers, however, there was an indication that the blood plasma concentrations might be affected by the living and working environment.

Elimination of a rhythmic movement disorder with hypnosis--a case report

The following describes a case of rhythmic movement disorder successfully treated with hypnosis. Hypnosis and its use in sleep disorders are discussed, and it is hypothesized that hypnosis is an effective intervention in disorders that occur at the interface between waking and sleep.

High resolution DNA fiber-fish on yeast artificial chromosomes: direct visualization of DNA replication

Fluorescent in situ hybridization (FISH) is a powerful, direct and sensitive technique with a wide resolution range that enables the simultaneous study of multiple targets, labelled in different colours. Spreading techniques, denoted here as 'Fiber-FISH', increase FISH-resolution to the DNA fiber, using decondensed nuclear DNA as hybridization target. FISH could be a powerful analytical tool for thorough physical examination of yeast artificial chromosomes (YACs) which are often chimaeric or contain internal deletions. However, with one exception restricted to meiotic yeast chromosomes, FISH has not been used successfully on yeast/YAC DNA. We have developed a fast and simple method that can be applied routinely for compositional and structural analysis of cosmid and YAC DNA in yeast. It enables precise localization and ordering of clones, resolves overlaps and distances and gives a detailed picture of the integrity and colinearity of both probe and target. The combination of high resolution, signal abundance and short yeast cell cycle allows direct visualization of replicating DNA fibers. In a 400 kb region of the human dystrophin gene, we identified two replication origins, demonstrating that human DNA cloned in yeast is capable of initiating its own replication.

In Rhizobium meliloti, the operon associated with the nod box n5 comprises nodL, noeA and noeB, three host-range genes specifically required for the nodulation of particular Medicago species

In Rhizobium meliloti, the genes required for nodulation of legume hosts are under the control of DNA regulatory sequences called nod boxes. In this paper, we have characterized three host-specific nodulation genes, which form a flavonoid-inducible operon down-stream of the nod box n5. The first gene of this operon is identical to the nodL gene identified by Baev and Kondorosi (1992) in R. meliloti strain AK631. The product of the second gene, NoeA, presents some homology with a methyltransferase. nodL mutants synthesize Nod factors lacking the O-acetate substituent. In contrast, in strains carrying a mutation in either noeA or noeB, no modification in Nod-factor structure or production could be detected. On particular hosts, such as Medicago littoralis, mutants of the n5 operon showed a very weak nodule-forming ability, associated with a drastic decrease in the number of infection threads, while nodulation of Medicago truncatula or Melilotus alba was not affected. Thus, nodL noeA and noeB are host-specific nodulation genes. By using a gain-of-function approach, we showed that the presence of nodL, and hence of O-acetylated Nod factors, is a major prerequisite for confering the ability to nodulate alfalfa upon the heterologous bacterium Rhizobium tropici.

Gas chromatographic-mass spectrometric determination of chlorophenols in the urine of sawmill workers with past use of chlorophenol-containing anti-stain agents

The aim of this work was to establish whether workers at sawmills where chlorophenol-containing anti-stain agents had been previously used were still exposed to chlorophenols. A gas chromatographic-mass spectrometric (GC-MS) procedure for the determination of chlorophenols in urine was developed. Chlorophenols were determined from hydrolysed urine as acetylated derivatives and determined by GC-MS using selected ion monitoring (SIM). Isolation of the chlorophenols with toluene gave the best extraction efficiencies (65-119%). Stability tests at -20 degrees C showed no degradation of the chlorophenols studied during 6 months. The limit of quantification was 3.6 ng mg-1 creatinine for 2,4,6-trichlorophenol, 5.5 ng mg-1 for 2,3,4,6-tetrachlorophenol and 3.6 ng mg-1 for pentachlorophenol. Traces of 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol were found both in previously exposed workers and in non-exposed controls, the urinary concentrations ranging from 1.1 to 15.9 ng mg-1 creatinine. The concentrations of urinary chlorophenols in previously exposed workers were of the same magnitude as those found in non-exposed controls and in the general population. The results show that it is unlikely that sawmill workers would be currently occupationally exposed to chlorophenols or polychlorinated dibenzo-p-dioxins and dibenzofurans via a contaminated work environment.

Judgments of azimuth and elevation as a function of monoscopic and binocular depth cues using a perspective display

The purpose of this study was to investigate the use of three-dimensional display formats for judgments of spatial information using an exocentric frame of reference. Eight subjects judged the azimuth and elevation that separated two computer-generated objects using either a perspective or stereoscopic display. Errors, which consisted of the difference in absolute value between the estimated and actual azimuth or elevation, were analyzed as the response variable. The data indicated that the stereoscopic display resulted in more accurate estimates of elevation, especially for images aligned approximately orthogonally to the viewing vector. However, estimates of relative azimuth direction were not improved by use of the stereoscopic display. Furthermore, it was shown that the effect of compression resulting from a 45-deg computer graphics eye point elevation produced a response bias that was symmetrical around the horizontal plane of the reference cube, and that the depth cue of binocular disparity provided by the stereoscopic display reduced the magnitude of the compression errors. Implications of the results for the design of spatial displays are discussed.

A dental and medical approach to sleep apnea. Part I: An overview of sleep apnea

Over the last decade there has been increasing evidence that obstructive sleep apnea is a common and potentially serious medical problem. Until recently the condition was primarily dealt with by pulmonary, sleep, and ENT physicians. With the development of the oral mandibular advancement devices for the treatment of sleep apnea, dentists have played an increasing role in the treatment of the condition. This series of articles will review the pathophysiology, clinical manifestations, diagnostic strategies and treatment options for this condition.

Selection of adrenal tumor cells in culture demonstrated by interphase cytogenetics

Solid tumors often consist of an admixture of cell populations with different genome constitutions. Karyotyping of this material is complicated by the low mitotic index. Even when chromosome studies are feasible, altered representation of the original cell populations after cell cultivation is possible. We report a human adrenal carcinoma that exhibited a normal karyotype after cultivation but was shown to be highly aneuploid when investigated by fluorescence in situ hybridization (FISH) in direct preparations of uncultured cells with six different centromeric probes. The high frequencies of trisomy for the investigated chromosomes in these interphase cells indicate that most of the tumor cells were in the triploid range. Strong selection for disomic cells was detected in interphase preparations after one and two subcultures and was even stronger in the corresponding metaphase preparations. Trisomy for chromosome 15 appeared to be maintained independent of triploidy and might play a role in cultured cell survival. The number of chromosome 17 centromeres was not increased in polyploid cells, suggesting loss of this chromosome in the original cells of the tumor.

The effect of zidovudine and 2'3'-dideoxyinosine on human trophoblast in culture

Trophoblast from term and first trimester placenta, maintained in culture, were exposed to 20 mumoles/l zidovudine or 2'3'dideoxyinosine. Several indices of function were measured and compared to control trophoblast in parallel culture. The results from individual placentas were examined by Student's t-test and cumulative results by ANOVA. Neither zidovudine or 2'3'-dideoxyinosine had statistically significant effects on the function of term trophoblast, following a 48 hr exposure to the drug as indicated by hCG secretion, protein synthesis and glucose consumption. In one of five placentas exposed to zidovudine, progesterone secretion was reduced as compared to its control but remained in the high range. Zidovudine had no significant effect on cultured trophoblast isolated from first trimester placenta even after prolonged exposure to the drug for eleven days. Both term and first trimester trophoblast in culture tolerate prolonged exposure to high concentrations of zidovudine or 2'3'-dideoxyinosine. Human trophoblast in culture provides a safe in vitro model for the screening of drugs intended for use during pregnancy.

Increased cholecystectomy rates among Medicare patients after the introduction of laparoscopic cholecystectomy

A study was undertaken of Medicare claims coded for cholecystectomy and those coded for laparoscopic cholecystectomy for the four year period 1990-1993 in New York State. During this time period there was a 28.12% increase in total cholecystectomies performed and an increase in the proportion of laparoscopic cholecystectomies from 15.86% to 50.0%. The increase in total cholecystectomies appears to be driven by a dramatic increase in laparoscopic procedures. Possible reasons for this increase include the performance of laparoscopy on patients previously assessed as too risky to undergo the conventional procedure, laparoscopy on mildly symptomatic patients who had previously put off a perceived higher risk open procedure and a possible broadening of indications for gallbladder surgery. The dramatic increase in the numbers of cholecystectomies performed in the early 1990s may be due in part to procedures performed on a large pool of procrastinating mildly symptomatic patients. If this is the case, then these increased rates should decline to baseline levels as soon as this pool of patients is exhausted. However, if surgeons are performing laparoscopy on asymptomatic patients with gallstones, then these rates may well be sustained. Such a broadening of indications for gallbladder surgery is of concern to many and has prompted the issuance of guidelines concerning the treatment of gallstones. Any broadening of indications for gallbladder surgery also has significant implications for health care costs and the use of health care resources.

Effect on fetal mouse development of exposure to MR imaging and gadopentetate dimeglumine

Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrificed and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed.

The effects of topical hypothermia and steroids on ATP levels in an in vivo liver ischemia model

Complex hepatic surgery often requires occlusion of the portal triad in order to decrease parenchymal bleeding. This study was undertaken to evaluate the effects of topical hypothermia and intravenous steroids on liver ischemia by measuring adenosine triphosphate (ATP) levels within the hepatic parenchyma. Forty New Zealand white rabbits were divided into four experimental and four control groups. All experimental animals underwent laparotomy and ligation of the porta hepatis. Serial liver biopsy specimens were obtained at predetermined time intervals. Group I received no further intervention. Group II were topically cooled until intrahepatic temperature reached 30 degrees C. Group III received preligation intravenous methylprednisolone (30 mg/kg). Group IV received both steroids and topical hypothermia. The corresponding control groups underwent laparotomy and isolation of the porta without ligation. Adenosine triphosphate was extracted from the liver parenchyma and quantified by high-performance liquid chromatography (HPLC). The data were analyzed using a three-factor mixed analysis of variance (ANOVA). There was a statistically significant protective effect on ATP levels provided by topical hypothermia at 15 and 30 minutes of ischemia (p < 0.01), but not at 60 minutes (p > 0.05). Steroids were not found to have any protective effect on ATP levels at any time point. The combination of steroids and topical hypothermia provided significant preservation of hepatic parenchymal ATP levels, although less than that of hypothermia alone, at 15 and 30 minutes of ischemia (p < 0.01).

Visual loss in pregnant women with pituitary adenomas

OBJECTIVE

To investigate the potential risk for developing visual loss during single or multiple pregnancies in women with pituitary adenomas.

DESIGN

Cohort study.

SETTING

Referral center of a neuro-ophthalmology service.

PATIENTS

65 consecutive women with pituitary adenomas who had not been previously treated with surgery or radiation were monitored during 111 pregnancies. Sixty had increased levels of serum prolactin or growth hormone and 5 did not.

MAIN OUTCOME MEASURES

Visual field or acuity loss was compared with the baseline size of the adenoma measured on the coronal view of the computed tomographic or magnetic resonance image.

RESULTS

Computed tomography or magnetic resonance imaging showed a definitive tumor (> 0.3 cm, vertical height) in 57 patients, 8 of whom had macroadenomas (> or = 1.1 cm). Visual field loss occurred in 6 of 8 primiparous patients, all with adenomas greater than 1.1 cm (range, 1.2 to 2.5 cm). None of the 57 patients (95% CI, 0% to 6.3%) with a microadenoma or presumed microadenoma of 1 cm or smaller developed visual loss after as many as four full-term pregnancies.

CONCLUSIONS

The risk for developing visual loss during single or multiple pregnancies in patients with microadenomas was small. Six of eight pregnant women with macroadenomas, however, developed visual field loss during pregnancy.

Assessment of the validity and utility of a sleep-symptom questionnaire

Although questionnaires have been developed to assess symptoms of obstructive sleep apnea (OSA), their overall reliability and utility have not been established. We have evaluated the ability of a questionnaire to identify increased apnea activity (IAA) in 465 participants in an epidemiologic study of OSA. Subjects and their roommates each completed a questionnaire and underwent in-home sleep studies. Responses to 56 questions about sleep habits, sleepiness, and daytime performance were analyzed with factor analysis, logistic regression, and receiver-operator curves (ROCs). Factor analysis demonstrated that 16 questions, grouped into five factors (functional impact of sleepiness, self-reported breathing disturbances, roommate-observed breathing disturbances, driving impairment, and insomnia) explained 67% of the variance in the questionnaire data. Symptom questions demonstrated internal consistency (Cronbach correlations: 0.91 to 0.98). Moderate levels of agreement were observed between self- and roommate-reported responses for nine of ten questions asked of both the subject and his/her partner (kappa statistics: 0.34 to 0.57). Logistic regression analysis demonstrated that IAA could be best predicted by three questions about intensity of snoring, roommate-observed choking, and having fallen asleep while driving (ROC area: 0.78). Use of symptoms with data on gender and body mass index (BMI) improved predictive ability by 10% (ROC area: 0.87). Thus, questionnaire data provide a valid means of characterizing symptom distributions in population surveys of OSA. Predictive ability is not significantly improved with multiple questions or a separate roommate questionnaire, but is improved with consideration of data on BMI and gender.

Genetic alterations of chromosome 17 in human breast carcinoma studied by fluorescence in situ hybridization and molecular DNA techniques

Fluorescence in situ hybridization (FISH) with a chromosome 17 centromere-specific probe was used together with Southern blot analyses and PCR amplification of a polymorphic segment to characterize 13 breast carcinomas. Cells with an abnormal number of chromosome 17 centromeres were found mixed with disomic cells in nine of the 13 tumors studied. Three of the four cases found to have a normal number of chromosome 17 centromeres had DNA alterations restricted to allelic imbalance of the two most distal markers on 17p; the fourth had no detectable alterations. In contrast, of the seven tumors found to have genetic alterations elsewhere on chromosome 17, all had more than one cell population when examined for numerical chromosome 17 alterations. The present data support the hypothesis that alterations at the distal short arm of chromosome 17 represent earlier events in the tumorigenic process than do the other chromosome 17 abnormalities observed. The results of molecular DNA studies interpreted as allelic imbalance of distal 17p markers in most cases probably reflect chromosomal rearrangements like loss of specific loci, rather than monosomies and large deletions. The report illustrates the usefulness of FISH when added to current molecular DNA techniques.

Citalopram and imipramine in the treatment of depressive patients in general practice. A Nordic multicentre clinical study

Two dose levels of citalopram, 10-30 mg and 20-60 mg, were compared with imipramine, 50-150 mg, in depressed patients treated in general practice. This was a multicentre study carried out in Denmark, Sweden, Norway, and Finland. The duration of treatment was 6 weeks with an optional continuation phase of a further 16 weeks. The patients were assessed by means of the Hamilton Rating Scale for Depression (HAMD), Clinical Global Impressions (CGI), and a visual analogue self-rating scale for depression. Observed and spontaneously reported adverse events were recorded. A total of 472 patients were entered into the study and 400 patients completed the 6 week trial period. A total of 297 patients completed the optional 22 week double-blind period. A clear reduction of the HAMD total scores was seen in all three treatment groups with no significant differences between groups. A reduction of the HAMD anxiety factor and sleep factor scores was also seen with no significant differences between treatments. The imipramine-treated patients showed a higher frequency of adverse events, especially the anticholinergic type, than citalopram-treated patients. Most patients entered into the continuation phase remained well.

Genotoxicity of kraft pulp spent liquors from different types of chlorination procedures

The genotoxicity of spent liquors from kraft softwood and hardwood pulp bleaching processes was studied using the Ames Salmonella test and the SOS chromotest. The induction of micronuclei, in vivo, was assayed in bone marrow erythrocytes of B6 mice treated with softwood first chlorination stage spent liquor. The softwood bleaching process used a combination of Cl2 and ClO2 at the first chlorination stage. During the study the amount of free chlorine at the first chlorination stage in the softwood bleachery was gradually decreased, although the amount of active chlorine remained the same. Enzymatic bleaching was also used in a softwood process together with chlorine (Cl2 + ClO2). The hardwood bleaching plant used only ClO2 at the first chlorination stage. A decrease in genotoxicity, corresponding to the decrease in Cl2, was observed in the Ames Salmonella assays of the softwood bleaching plant effluents. A similar decrease was observed in the SOS chromotest. The highest decrease in mutagenic activity was observed when enzymatic bleaching was used together with chlorine.

Intragenic reorganization of RB1 in a complex (4;13) rearrangement demonstrated by FISH

Reciprocal chromosome translocations with no apparent loss of material are the most common de novo structural rearrangements in man. The large majority of these cases have been characterized cytogenetically but very few have been investigated at the molecular level. Using fluorescence in situ hybridization (FISH) we have studied the organization of the tumor suppressor gene RB1 in a patient with retinoblastoma and a rearrangement between chromosomes 4 and 13. In addition to the hybridization signal on the normal chromosome 13, three distinct sites of hybridization of RB1 probes on the translocated chromosomes were detected. These findings show that a complex rearrangement occurred involving at least three breaks on chromosome 13, two of them in the RB1 gene. This also demonstrates that FISH, which offers resolution between that of fine molecular methods and classical cytogenetics, is a valuable tool for investigating organization of sequences at breakpoints of chromosomal rearrangements.

Reliability of measurements of total, protein-bound, and unbound estradiol in serum

Estradiol (E2) circulates in the blood in three states: unbound (U-E2), bound to sex-hormone binding globulin (SHBG-E2), and bound to albumin. There is evidence to support the concept that only U-E2 and albumin-bound E2, are bioavailable (i.e., rapidly extracted by tissues). A case-control study nested within a large cohort of women, in which we are examining the effect of estrogens on breast cancer risk, offered the opportunity to assess the reliability of measurements of E2, the percentage of SHBG-E2, and the percentage of U-E2 based on multiple annual serum specimens. Long-term (1-2 year) reliability, as estimated by the intraclass correlation coefficient, was assessed in a subgroup of 71 premenopausal and 77 postmenopausal controls for whom two or three serum specimens were assayed. In postmenopausal women the intraclass correlation coefficient for a single measurement of total E2 was only 0.51. As for the percentage of SHBG-E2, intraclass correlation coefficients were 0.83 and 0.94, and for U-E2, 0.72 and 0.77 in the premenopausal and postmenopausal groups, respectively. These data suggest that, whereas single determinations of total E2 are insufficient to reliably estimate a woman's true mean level, a single measurement of the percentage of SHBG-E2 or U-E2 is adequate to assess bioavailability of E2 in an epidemiological study, irrespective of day of the menstrual cycle.

Antinociception without motor blockade after subarachnoid administration of S-(+)-ibuprofen in rats

This study was designed to determine whether the nonsteroidal anti-inflammatory drug (NSAID) sodium S-(+)-ibuprofen (IB), can be used intrathecally as a substitute analgesic for opiates to avoid the side effects of intrathecal narcotics. One week or more after surgical implantation of subarachnoid catheters, four groups of Sprague-Dawley rats were given 0.05 ml subarachnoid injections containing one of the following: Group A, normal saline (NS); Group B, IB 0.25 mg, 0.5 mg and 1.5 mg; Group C, morphine (M) 0.05 mg and 0.025 mg; Group D received NS or IB 1.5 mg. Animals were sacrificed for spinal cord examination one week after injection. Tail flick response latency (TFL) was determined before and 15, 30, 60, 120 and 180 minutes after each injection. TFL differences were compared. IB 1.5 mg vs NS, IB 0.5 mg vs NS, IB 0.25 mg vs M 0.05 mg, IB 0.25 mg vs M 0.025 mg, M 0.05 mg vs NS, and M 0.025 vs NS showed p < 0.05. IB 1.5 mg vs M 0.05 mg and M 0.025 mg, IB 0.5 mg vs M 0.05 mg and M 0.025 mg revealed no significant difference. No motor impairment was observed in any animal. Light microscopy of the spinal cord revealed no evidence of pathological changes in any animal (group D).

Nonrandom inactivation of the Y-bearing X chromosome in a 46,XX individual: evidence for the etiology of 46,XX true hermaphroditism

We previously reported a subject with 46,XX true hermaphroditism who had a 46,X,del(X) karyotype and Y-chromosomal sequences in genomic DNA. We hypothesized that the Y-chromosomal sequences were translocated to the deleted X chromosome and that the incomplete testis determination of this individual was the result of inactivation of the translocated X chromosome. In situ hybridization studies demonstrated that the Y-chromosomal sequences were located on the distal portion of the short arm of the deleted X chromosome. Investigation of the replication of the X chromosome, using a modified R-banding technique and localization of Y-chromosomal sequences by in situ hybridization, showed that the translocated X chromosome was late replicating in all 100 EBV-transformed lymphoblasts that were examined. By contrast, when cells from a subject with 46,XX maleness were studied, the translocated X chromosome was late replicating in only 21 of 47 cells. As the late-replicating X chromosome is presumed to be the inactive X chromosome, selection of cells in which the Y-bearing X chromosome has been inactivated may play a role in the incomplete testis determination in subjects with "Y-positive" 46,XX true hermaphroditism.

A modified transvaginal sonographic technique for better ovarian evaluation

Sonographic evaluation of the pelvis of postmenopausal women is not complete until both ovaries are scanned. Transvaginal sonographic examination combined with transabdominal screening is diagnostic in 85% of cases. Transvaginal examination performed with a partially full bladder significantly increased ovarian detection to 93.5% (p < 0.05).

The association between hypertension and sleep apnea in obese patients

Strong associations have been demonstrated between hypertension (HTN) and obesity, and obesity and sleep apnea (SA). However, it is unclear whether previously suggested relationships between HTN and SA were based on causal mechanisms, or rather, were confounded by obesity. To investigate whether SA may be an independent predictor of HTN, we measured respiration during sleep and BP in 19 participants in a hospital-based weight control program. Additionally, subjects underwent cephalometry, measurement of weight and hip circumferences, and pulmonary function tests. Studies were repeated in 14 subjects following weight loss. Subjects consisted of 9 men and 10 women, ages 43 +/- 11 years (mean +/- SD), and weight of 114 +/- 20 kg. Hypertension (diastolic BP > 95 mm Hg, systolic BP > 160 mm Hg, or a report of current use of an antihypertensive medication) was present in 6 (32 percent) subjects. Sleep apnea was more prevalent among the hypertensive (5/6; 83 percent) than normotensive (2/13; 15 percent) subjects (p < 0.01); respiratory disturbance index (RDI) was 42.4 +/- 16.0 vs 6.2 +/- 2.3 (p < 0.01) in these groups. Compared with normotensive subjects, hypertensive subjects were of similar weight, but had greater central obesity and had lower levels of vital capacity. Regression analyses demonstrated that RDI was the strongest independent predictor of BP level, accounting for approximately 60 percent of the variability in this measurement. Following weight loss, BP and RDI both significantly declined, soft palate width decreased, and vital capacity increased. Thus, in this group of obese subjects, BP level was associated most significantly with the magnitude of sleep-related respiratory disturbances. The obese subjects who are most likely to have SA and HTN are male and/or subjects with greater central obesity and lower vital capacity.

Chronic pain in a geographically defined general population: studies of differences in age, gender, social class, and pain localization

OBJECTIVE

To establish basic epidemiological data on chronic pain (duration > 3 months) in a defined population. Relationships between age, gender, and social class were tested.

DESIGN

A survey of pain symptoms, including location, intensity, duration, and functional capacity, was conducted by means of a mail questionnaire.

SETTING

General populations in two Swedish primary health care districts. Medical care was provided in a state health system.

SUBJECTS

A random sample (from the population register) of 15% of the population aged 25-74 (n = 1,806). The response rate was 90%.

OUTCOME MEASURES

Descriptive epidemiologic data in relation to objectives of the study.

RESULTS

Without sex differences, 55% (95% confidence interval, 53-58%) of the population had perceived persistent pain for 3 months and 49% for 6 months. Among individuals with chronic pain, 90% localized their pain to the musculoskeletal system to a variable extent. Women experienced more multiple localizations of pain and had pain in the neck, shoulder, arm, and thigh to a greater extent than men. Prevalence of pain increased by age up to 50-59 years for both genders and then slowly decreased. The neck-shoulder area was the most common site of pain (30.2%), followed by the lower back (23.2%). Even in the youngest age groups more than one of four reported chronic pain. Blue-collar workers and employers (including farmers) reported chronic pain to a greater extent than other groups. In 13% of the population, manifest pain problems were associated with reduced functional capacity.

CONCLUSION

Chronic pain symptoms are common but unevenly distributed in a general population. The results may influence planning and consultation in primary health care as well as warranting selective prevention activities.

Unbalanced translocation, t(18;21), detected by fluorescence in situ hybridization (FISH) in a child with 18q- syndrome and a ring chromosome 21

We report on an 8-year-old girl with minor anomalies consistent with 18q- syndrome and mild developmental delay. Initially cytogenetics showed a terminal deletion of chromosome 21 with mosaicism for a small ring chromosome 21 as the only apparent karyotypic abnormality: mos 45,XX,-21/46,XX,+r(21) (48%/52%). Further studies including FISH and DNA analysis demonstrated a de novo unbalanced translocation of chromosomes 18 and 21 with the likely breakpoints in 18q23 and 21q21.1. Most of 21q was translocated to the distal long arm of one chromosome 18, and this derivative 18 appeared to lack 18q23-qter. The small ring chromosome 21 [r(21)], present in only 52% of the patient's blood lymphocytes, did not appear to be associated with the abnormal phenotype since all 13 chromosome 21 markers that were examined in genomic DNA were present in 2 copies, and the phenotype of the patient was consistent with the 18q- syndrome. The karyotype was reinterpreted as mos 45,XX,-18,-21,+der(18) t(18;21) (q23;q21.1)/46,XX,-18,-21,+der(18) t(18;21) (q23;q21.1), +r(21) (p13q21.1) (48%/52%). These results demonstrate the power of FISH in conjunction with DNA analysis for examination of chromosome rearrangements that may be misclassified by traditional cytogenetic studies alone.

The use of computer-assisted diagnosis in cardiac perfusion nuclear medicine studies: a review (Part 3)

Computer-assisted diagnosis (CAID) is commonly used to evaluate cardiac nuclear medicine studies such as thallium perfusion scans. Part 1 of this series (Journal of Digital Imaging, 5:209-222, 1992) reviewed the basic theory underlying CAID in nuclear medicine and its use in planar thallium imaging. Part 2 discussed the application of CAID to SPECT perfusion studies (Journal of Digital Imaging, 6:1-15, 1993). This article reviews new variations of CAID programs for SPECT imaging and the application of expert systems and neural networks to CAID of nuclear medicine perfusion studies.

A Neural Network That Learns to Interpret Myocardial Planar Thallium Scintigrams

The planar thallium-201 (201Tl) myocardial perfusion scintigram is a widely used diagnostic technique for detecting and estimating the risk of coronary artery disease. Interpretation is currently based on visual scoring of myocardial defects combined with image quantitation and is known to have a significant subjective component. Neural networks learned to interpret thallium scintigrams as determined by both individual and multiple (consensus) expert ratings. Four different types of networks were explored: single-layer, two-layer backpropagation (BP), BP with weight smoothing, and two-layer radial basis function (RBF). The RBF network was found to yield the best performance (94.8% generalization by region) and compares favorably with human experts. We conclude that this network is a valuable clinical tool that can be used as a reference "diagnostic support system" to help reduce inter- and intraobserver variability. This system is now being further developed to include other variables that are expected to improve the final clinical diagnosis.

Localization of the 70-kDa peroxisomal membrane protein to human 1p21-p22 and mouse 3

The 70-kDa peroxisomal membrane protein (PXMP1) is a member of the ATP-binding cassette transporter family. In humans, mutations in this gene may be responsible for a subset of patients with Zellweger syndrome, a lethal inborn error of peroxisome assembly. The PXMP1 gene was assigned to human chromosome 1p21-p22 by in situ hybridization and its murine homologue (Pxmp-1) to chromosome 3 by interspecific backcross analysis.

Distribution of 3H-morphine after lumbar epidural administration in unanesthetized rabbits

BACKGROUND AND OBJECTIVES

This study focused on the distribution of 3H-morphine in the spinal cord, roots, urine, and blood, after epidural administration in rabbits.

METHODS

Under nitrous oxide, halothane, and oxygen endotracheal anesthesia, the cisterna magna of New Zealand albino rabbits was cannulated for cerebrospinal fluid sampling, and catheters were placed in the lumbar epidural space. Through the epidural catheter, 200 pmol of 3H-morphine contained in 500 microliters of 1.3 mM (0.21 mg) morphine was injected. Arterial blood and cisternal CSF were sampled at 0, 5, 15, 30, 45, 60, 90, and 120 minutes after injection. Animals were killed with intravenous pentobarbital at the end of 120 minutes (n = 3), 6 hours (n = 4), and 12 hours (n = 2). In each animal the brain, spinal cord, spinal roots, liver, kidneys, and urinary bladder were removed.

RESULTS

The injection site over the cord was identified and all tissues were immediately frozen at -70 degrees C. Two-mm thick cross-sections, were taken from every centimeter of the spinal cord. Radioactivity in the series of sections was determined by scintillation spectroscopy. At 2 hours, 4.2% +/- 1.1% of the injected radioactivity was recovered, and at 6 hours 1.6% +/- 0.6% was recovered. Radioactivity was concentrated mainly around the lumbar injection site, and it decreased as the distance increased from the injection site and coincided with elapsed time after the injection.

CONCLUSION

Multiple linear regression analysis of radioactive labels showed the significant effect of time, distance from the injection site, and the time-distance interaction on the distribution of 3H-morphine in the spinal cord (p < 0.0001 for time and rostral and caudal distance from the injection site; and p < 0.0001 for interaction between time and distance.) A major portion of the injected radioactivity was recovered in the urine and a small amount in other tissues and body fluid: bladder, liver, spinal roots, kidney, plasma, and cerebrospinal fluid.

Signaling and host range variation in nodulation

Rhizobium, Bradyrhizobium, and Azorhizobium strains, collectively referred to as rhizobia, elicit on their leguminous hosts, in a specific manner, the formation of nodules in which they fix nitrogen. Rhizobial nod genes, which determine host specificity, infection, and nodulation, are involved in the exchange of low molecular weight signal molecules between the plant and the bacteria as follows. Transcription of the nod operons is under the control of NodD regulatory proteins, which are specifically activated by plant flavonoid signals. The common and species-specific structural nod genes are involved in turn in the synthesis of specific lipo-oligosaccharides that signal back to the plant to elicit root-hair deformations, cortical-cell divisions, and nodule-meristem formation.

Surgical treatment of incompetent cervix

A comparison of multiple factors in the surgical management of cervical incompetence was carried out in 114 procedures. Factors examined included training level of the operator, gestational age, cervical effacement and dilation at the time of operation, diagnostic evaluation, Shirodkar or McDonald procedure, year of the procedure, and tocolytic therapy. The endpoint for successful outcome was defined as 37 weeks or newborn weighing over 2500 gm rather than neonatal survival, thus differing from previous studies. All patients were delivered vaginally unless there was an obstetric indication for cesarean delivery. The most important determinants of a term birth in patients with incompetent cervix were operator experience and the use of a Shirodkar procedure.

Impact of do-not-resuscitate legislation on the use of cardiopulmonary resuscitation in three teaching hospitals

Under New York State's unique do-not-resuscitate law, patients admitted to a hospital are assumed to consent to cardiopulmonary resuscitation unless a do-not-resuscitate order has been written in accordance with specific stipulations. This study was undertaken to determine if the law would significantly change the use of cardiopulmonary resuscitation. The charts of 952 patients who died on the medical services of Bellevue, New York University, and New York Veterans hospitals during the 12-month periods before and after the law went into effect were reviewed. The proportion of patients undergoing cardiopulmonary resuscitation was determined. To take into account the effects of potential confounders (ie, hospital, sex, race or ethnic group, age, diagnosis), a multiple logistic regression analysis was performed. The relative risk for cardiopulmonary resuscitation was found to be 0.81, (95% confidence interval: 0.59-1.10) after the law as compared with before, which was not statistically significant. Although patients with chronic or potentially reversible illness were much more likely than those with hopeless illness to undergo cardiopulmonary resuscitation (relative risk of 7.08 [3.23-15.54] and 12.89 [8.71-19.07], respectively), the data failed to show that the law had an impact on the use of cardiopulmonary resuscitation in any of the disease categories. Total use of formal do-not-resuscitate orders increased from 32.7% to 83.9% (p less than .0001), although at Bellevue, where documentation was high before the law, no further increase occurred.(ABSTRACT TRUNCATED AT 250 WORDS)