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PubMed1992

Lip cancer. Incidence trends in Connecticut, 1935-1985.

Suspicions have recently arisen that cancer of the lip may exert an undue influence on overall oral cancer statistics and, therefore, possibly distort the true image of intraoral cancer. The authors investigated this question through epidemiologic analysis. A total of 2291 cases of lip cancer accessioned by the Connecticut Tumor Registry (CTR) from 1935 to 1985 (23.6% of all oral cancer) were analyzed. Occurrence trends for males and females had different patterns: for men, the age-adjusted incidence rates showed a fivefold decrease during the 51-year study; for women, the rates were relatively low and constant during the same period. Analysis for age-specific rates revealed that the older the age group, the higher the incidence rates for both sexes. Squamous cell carcinoma accounted for at least 87.4% of all lip cancers (96.2% if nonspecified epithelial neoplasms are assumed to be squamous cell carcinoma). The vermilion border of lower lip was the most common site. Moderately differentiated tumors were most common (48.5%), closely followed by well-differentiated tumors (44.2%). Analysis by county showed that the crude incidence rates for males in New London and Windham counties exceeded the average Connecticut statewide rates. The authors concluded that the epidemiology of Connecticut lip cancer differs significantly from that of intraoral squamous cell carcinoma in the same population studied within the same period of time. Epidemiologic studies involving "oral cancer" should direct attention to anatomic subsite to consider differences in disease trends according to specific location.

Adenocarcinoma↗
PubMed2003

Mapping the literature of clinical laboratory science.

This paper describes a citation analysis of the literature of clinical laboratory science (medical technology), conducted as part of a project of the Nursing and Allied Health Resources Section of the Medical Library Association. Three source journals widely read by those in the field were identified, from which cited references were collected for a three-year period. Analysis of the references showed that journals were the predominant format of literature cited and the majority of the references were from the last eleven years. Applying Bradford's Law of Scattering to the list of journals cited, three zones were created, each producing approximately one third of the cited references. Thirteen journals were in the first zone, eighty-one in the second, and 849 in the third. A similar list of journals cited was created for four specialty areas in the field: chemistry, hematology, immunohematology, and microbiology. In comparing the indexing coverage of the Zone 1 and 2 journals by four major databases, MEDLINE provided the most comprehensive coverage, while the Cumulative Index to Nursing and Allied Health Literature was the only database that provided complete coverage of the three source journals. However, to obtain complete coverage of the field, it is essential to search multiple databases.

Abstracting and Indexing↗
PubMed2001

Partly ordered synthesis and degradation of glycogen in cultured rat myotubes.

The following questions concerning glycogen synthesis and degradation were examined in cultured rat myotubes. 1) Is synthesis and degradation of the individual glycogen molecule a strictly ordered process, with the last glucosyl unit incorporated into the molecule being the first to be released (the last-in-first-out principle), or is it a random process? 2) Are all glycogen molecules in skeletal muscle synthesized and degraded in phase (simultaneous order) or out of phase (sequential order)? Basal glycogen stores were minimized by fasting and were subsequently replenished in two intervals, the first (0-0.5 h) with tritium-labeled and the second (0.5-3 h) with carbon-labeled glucose as precursor. Glycogen degradation was initiated by addition of forskolin. The kinetics of glycogen accumulation as well as degradation could be approximated by monoexponential equations with rate constants of 0.81 and 1.39 h(-1), respectively. The degradation of glycogen largely followed the last-in-first-out principle, particularly in the initial period. Analysis of the size of the glycogen molecules and the beta-dextrin limit during glycogen accumulation and degradation showed that both synthesis and degradation of glycogen molecules are largely sequential and the small deviation from this order is most pronounced at the beginning of the accumulation and at the end of the degradation period. This pattern may reflect the number of synthase and phosphorylase molecules and fits well with the role of glycogen in skeletal muscle as a readily available energy store and with the known structure of the glycogen molecule. It is emphasized that the observed nonlinear relation between the change in glycogen concentration and release of label during glycogen degradation may have important practical consequences for interpretation of experimental data.

Animals↗
PubMed1993

Electroencephalographic sleep studies in depressed patients during long-term recovery.

Analytic electroencephalographic (EEG) sleep procedures were used to examine specific changes in rapid eye movement (REM) and slow wave sleep (SWS) as they unfolded during depressive illness and recovery. The subjects were 15 patients with recurrent depression who remained well during 3 years of nonpharmacologic maintenance treatment without a recurrent episode of major depression. The analyses were performed on EEG sleep studies conducted before acute treatment, after 3 months in maintenance treatment, and every 3 months thereafter for 3 full years of maintenance treatment. There was no change between the index sleep and sleep during the first year of maintenance treatment as determined by period analysis or visual inspection of REM sleep parameters, except that average REM counts decreased over time. Thus, it is possible that REM parameters may represent one indicator of long-term recovery from depression. Finally, a significantly higher amount of 12-20 Hz spectral power density was found during the index episode than during the period of remission.

Adult↗
PubMed1992

The recording and analysis of EMG and jaw tracking. I. The recording procedure.

A computer-based system is described which records and analyses electromyographic (EMG) signals and tracking data for mandibular movements during function. EMG signals were obtained bilaterally from six muscles and a Sirognathograph monitored the position of the lower incisor teeth in three dimensions. Directed jaw movement tasks by subjects were monitored. These data were continuously sampled at a rate of 1 KHz per channel over an operator controlled period. Analysis of the data was performed off-line following the experiment. Individual chewing cycles associated with masticatory function were identified and the timing and dimensions of each chewing envelope established. Corresponding EMG values were also determined and displays of EMG and jaw movement were plotted on a common time base. An average chewing cycle and correlated EMG activity could also be displayed on a high resolution monitor and plotted for a hard copy to enable a comparison to be made between subjects with and without jaw dysfunction.

Analysis of Variance↗
PubMedDate not supplied

[Choice of a scleroplasty method in progressive myopia in children].

Dynamic analysis of the results of sclera-fortifying interventions (scleroplasty and sclera-fortifying injection) in children aged 8 to 12 has demonstrated that in many cases myopia stabilized but temporarily after sclera fortification in children with progressive myopia. Repeated sclera-fortifying interventions reduced the rate of postoperative myopia progress approximately twofold, the myopia stabilization period lasting for 1 to 2 years; in some cases myopia progress ceased after a repeated intervention. In 67% of patients myopia on the second eye did not progress for 6 months after sclera-fortifying injection and for a year after scleroplasty on the first eye. Sclera fortification in the paired eye is advisable within these periods. Analysis of the results from the viewpoint of the general mechanisms of scleroplasty effect has lead the authors to a conclusion that sclera-fortifying therapy of children with high progressive myopia should be carried out in several stages. A system of sclera-fortifying treatment of progressive myopia has been developed, and the continuity of methods used for this purpose validated. Effects of this treatment scheme on refraction and status of the fundus oculi are estimated.

Age Factors↗
PubMed1992

The use of fluorescent probes to assess oxidative processes in isolated-perfused rat heart tissue.

The formation of reactive oxygen species (ROS) in intact heart tissue has been assessed by direct ESR measurements, and indirectly by the formation of characteristic tissue products and the protective effects of various antioxidants. The development of lipid soluble esters of compounds which can be trapped intracellularly after hydrolysis, and which fluoresce after oxidation, has provided a new tool to investigate ROS in vitro. The utility of 2',7'-dichlorofluorescin diacetate (DCFDA) in isolated-perfused rat heart tissue was investigated in the present study. DCFDA and its deacetylated form were incubated with various levels of hydrogen peroxide or t-butylhydroperoxide (tBOOH). Conversion of the diacetate form to a fluorescent product required 4-5 h with hydrogen peroxide and up to 24 h with tBOOH. In contrast, the deacetylated form fluoresced at 80% of maximum levels 1 h after the addition of 100 mM tBOOH. DCFDA was loaded into heart tissue by infusing for 10 min at a final concentration of 10 microM in Krebs-Henseleit bicarbonate buffer. After a 10 min washout period, analysis of freeze-clamped heart tissue revealed that the trapped material was readily converted to a fluorescent product by tBOOH, indicating hydrolysis had occurred. Fluorescence of material trapped in heart tissue was approximately 24% of the maximum achieved after oxidation with 100 mM tBOOH. This value decreased to 18 and 13% when the loading and washout periods were from 0 to 20 or 10 to 30 min of hypoxia, respectively. Similar results were obtained with the less readily oxidized dicarboxy derivative of DCFDA. Infusion of 500 microM tBOOH increased the oxidation of DCFDA in heart tissue from 24 to 31%.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Alteration of 24-hour rhythms in myometrial activity in the chronically catheterized pregnant rhesus monkey after a 6-hour shift in the light-dark cycle.

We determined the effect of a 6-hour phase shift in the light-dark cycle on the 24-hour rhythm of myometrial activity with 15 chronically catheterized pregnant rhesus monkeys during the last third of gestation. Monkeys were housed indoors in constant temperature on a 14-hour-light/10-hour-dark photoperiod in two groups based on the time the lights were turned on (group A lights on at 6 AM and group B lights on at midnight). The power spectra were calculated for periods of 512 readings (1.138 hours) starting at the time the lights were turned on for continuous periods of 25.03 hours of data showing well-developed contraction-type activity at any time during that period. The power spectra data for contractures and contractions were analyzed separately from myometrial electromyographic data. During the 14 hours of light, myometrial activity was primarily composed of contractures. In all experimental animals the switch from contractures to contractions occurred around the time the lights were turned off. The proportion of contraction-type activity in each 1.138-hour analysis interval expressed as a percentage of the total contraction power for the whole 25.03-hour analysis period for all monkeys increased around the time the lights were turned off in both groups. The increase in contractions was observed 12 to 15 hours after the lights were turned on. No systematic change in the proportion of contracture activity was observed. Peak contraction activity was 22.6 +/- 0.60 hours (16.6 hours after lights on), and was at 18.3 +/- 1.4 hours (18.31 hours after lights on) in groups A and B, respectively. This difference was statistically significant (22.6 +/- 0.6 vs 18.3 +/- 1.4 hours, p less than 0.05). Seven of eight monkeys in group A and six of seven in group B had switched from contractures to contractions before lights were turned off. We have confirmed a 24-hour rhythm in myometrial activity in the pregnant rhesus monkey and provided new evidence to support the endogenous nature of this rhythm and its direct relationship to the light-dark cycle.

Animals↗
PubMed1995

Human immunodeficiency virus type-1 seroconversion trends among young adults serving in the United States Army, 1985-1993. United States Military Medical Consortium for Applied Retroviral Research.

The direct measurement of the incidence of new infections with the human immunodeficiency virus type 1 (HIV-1) can be made among soldiers because of the routine and periodic nature of HIV-1 testing in the United States Army. Between November 1985 and October 1993, 978 HIV-1 seroconversions were seen among 1,061,768 soldiers, contributing over 3.6 million person-years of follow-up [seroconversion rate (95% confidence interval) = 0.27/1,000 person-years (0.25-0.29)]. A significant decreasing trend in HIV-1 seroconversion rates was seen over the analysis period. The rate of new infections declined significantly from the first interval, 1985-1987, (0.43/1,000 person-years) to the second interval, 1987-1988, (0.28/1,000 person-years), but stabilized at approximately 0.22/1,000 person-years after 1988, representing new infections in approximately 100-150 soldiers annually. The risk of seroconversion among active duty soldiers was significantly associated with racial/ethnic group, age, gender, and marital status. Surveillance of HIV-1 seroconversion rates in the U.S. Army continues to offer a unique opportunity to assess temporal trends in the evolving HIV-1 infection epidemic. Monitoring the rate of new HIV-1 infections allows for identification of subgroups in need of intervention, refocusing of intervention strategies, and evaluation of their effectiveness.

Adult↗
PubMed2006

Induction of cyclin D1 by submicromolar concentrations of arsenite in human epidermal keratinocytes.

Arsenic is a prevalent environmental carcinogen but arsenic is not directly mutagenic and the mechanism by which arsenite brings about oncogenic transformation is poorly understood. To gain insight into the oncogenic properties of arsenic, we studied the expression of cyclin D1 in cultured human epidermal keratinocytes treated with submicromolar concentrations of sodium arsenite. Arsenite at concentrations between 200 and 800 nM over a 3-day period brought about an increase in cell growth rate. Uptake of the vital stain, neutral red, arsenite at 200 and 400 nM concentrations brought about a parallel increase in cell viability over the same treatment period. Analysis of cell cycle parameters by flow cytometry showed that the growth stimulation was accompanied by a concomitant shift from the G1 into the S/G2 cell cycle compartment in the arsenite-treated cells. Real-time PCR analysis of cyclin D1 transcription showed that there was an induction of more than three-fold in cells exposed to 400 nM arsenite for 3 days. Quantitation of cyclin D levels in Western blots showed that arsenite treatment caused a time-dependent induction of cyclin D proteins representing an induction of about 2.0-fold after a 7 day treatment period. Electrophoretic mobility shift assays (EMSA) showed that arsenite also stimulated binding of the transcription factors, AP1 and CREBP to their respective binding motifs within 3 days. This supports a mechanism of oncogenesis based on persistent upregulation of D type cyclins leading to a concomitant loss of G1/S checkpoint control.

Arsenites↗
PubMedDate not supplied

Prevention of recurrent deep venous thrombosis with sulodexide: the SanVal registry.

The aim of this study was to evaluate the prevention of recurrent deep vein thrombosis (R-DVT) with an oral antithrombotic agent (sulodexide) in moderate to high-risk subjects. A group of 405 patients was included into the multicenter registry. Both compression and an exercise program were used as well as a risk-factors control plan. After diagnosis of DVT, patients were treated with oral anticoagulants for 6 months. At the end of this period a coagulation study was made and patients started treatment with oral sulodexide capsules for a period of 24 months. The femoral, popliteal, tibial, and superficial veins were scanned with high-resolution ultrasound at inclusion;scans were repeated at 6, 12, 18, and 24 months. Of the 405 subjects included into the registry 178 in the control group (mean age 52.2; SD 11; M:F=90:88) and 189 in the treatment group (mean age 53.2; SD 10.3; M:F=93:96) completed the analysis period of 24 months. At 6 and 12 months the incidence of R-DVT was lower (p<0.05) in the treatment group. At 24 months the global incidence of R-DVT was 17.9% in the control group and 7.4% in the sulodexide group (p<0.05), 2.42 times lower than in controls. The 2 groups were comparable for age and sex distribution and for the localization of the thrombi at inclusion. Also the 2 groups of dropouts were comparable. In the control group there were 32 recurrent DVTs and 24 subjects lost to follow-up (total of 56) of 202 included subjects (27.7%) in comparison with 28 failures (14 recurrent DVTs and 14 lost subjects) of 203 subjects (13.8%) in the treatment group. This difference was statistically significant. In this analysis the incidence of DVT in controls was 2.07 times higher than in the treatment group subjects. In conclusion sulodexide was effective in reducing recurrent thrombotic events in high-risk subjects.

Administration, Oral↗
PubMed1990

Starting to add worse: effects of learning to multiply on children's addition.

A major stumbling block in acquiring a new skill can be integrating it with old but related knowledge. Learning multiplication is a case in point, because it involves integrating new relations with previously acquired arithmetic knowledge (in particular, addition). Two studies explored developmental changes in the relations between single-digit addition and multiplication. In the first study, third-graders, fifth-graders, and adults performed simple addition or multiplication in mixed- and blocked-operations formats. Substantial interfering effects from related knowledge were found at all age levels, but were more pronounced for younger subjects. Thus in the early stages of learning multiplication, one consequence of learning a new operation is interference in performance of an earlier, related, but less recently studied skill. Consideration of error patterns supported the view that the problem of integrating operations is a prominent one even in the early stages of mastering multiplication. Patterns of errors were generally consistent across all age groups, and all groups were much more likely to give a correct multiplication response to an addition problem than the reverse. A second, longitudinal study confirmed this finding, showing evidence for impaired performance of addition over time within individual children (second-, third-, and fourth-graders) tested on simple addition and multiplication over a 5-month period. Analysis of reaction times for addition indicated that second-graders in advanced math classes and third-graders in regular math classes tended to slow down over the year in responses to addition problems. Fourth-graders, on the other hand, tended to increase their speed of addition over the course of the year. Multiplication showed a different pattern during this period, with no evidence for slowing among children who were able to perform this task. Disruption of previously learned knowledge in the course of acquiring new skills provides evidence that new knowledge and old knowledge are being integrated. This kind of non-monotonic development may provide an empirical method for determining the functional limits of a domain of knowledge.

Adult↗
PubMed2005

Persistence and pathways of testosterone dissipation in agricultural soil.

The persistence and pathways of dissipation of testosterone in three agricultural soils were examined in laboratory microcosm incubations at different soil moistures (1.7-39%) and temperatures (4-30 degrees C) using (14)C- and (3)H-labeled and unlabeled testosterone. Sterilized loam was also examined to assess possible abiotic pathways. Extractable (14)C decreased rapidly for all three soils at 30 degrees C with times to dissipate 50% of material (DT(50)) ranging from 8.5 to 21 h. Respired (14)CO(2) accounted for approximately 50% of the applied (14)C after 120 h. Androgenic activity of soil extracts declined faster than the extractable (14)C levels demonstrating that testosterone was not being converted to compounds with greater activity. Dissipation rates of nonvolatile, extractable (3)H in loam at 7, 15, and 39% moisture were similar, but the rate in air-dried loam (1.7% moisture) was significantly reduced. High performance liquid chromatography (HPLC) analysis of extracts of (14)C-testosterone-treated loam incubated at 30 degrees C for 6 h revealed that the (14)C was distributed among the remaining testosterone and three major metabolites (4-androstene-3,17-dione, 5alpha-androstane-3,17-dione, and 1,4-androstadiene-3,17-dione), which accounted for 48.7, 23.7, and 9.6% of the remaining (14)C, respectively. Periodic analysis of soil incubated at 23, 12, and 4 degrees C showed that the rates of testosterone dissipation and metabolite appearance and subsequent dissipation were temperature dependent with rates decreasing with decreasing temperature. In sterilized loam, 4-androstene-3,17-dione was the only metabolite detected. We conclude that testosterone is rapidly and thoroughly biodegraded in agricultural soils under a range of conditions typical of a temperate growing season and thus is unlikely to pose a long-term risk to adjacent aquatic environments.

Agriculture↗
PubMed1980

Classification and assessment of cerebral bioavailability of lopirazepam (D-12524) by quantitative EEG and psychometric analysis.

In this double-blind, placebo-controlled study the CNS efficacy and pharmacodynamic properties of 3-hydroxy-5-(o-chlorophenyl)-7-chloro-1,2-dihydro-3H-pyrido[3,2-e]-1,4-diazepin-2-one (lopirazepam, D-12524) was investigated in a group of 10 normal volunteers. Quantitative EEG and psychometric analyses and clinical evaluations were done before as well as 2, 4, 6 and 8 h after oral administration of single doses of placebo, 3 mg, 5 mg and 10 mg lopirazepam and 10 mg prazepam. EEG digital computer period analysis demonstrated dose-dependent changes which are typical of the class of anxiolytics and which started in the 2nd hour, peaked in the 4th hour and lasted after 3 mg, 5 mg and 10 mg up to the 4th, 6th and 8th hour, respectively, 10 mg D-12524 produced an additional augmentation of slow waves indicating sleep-inducing qualities in this dosage. The equipotent dosage to 10 mg prazepam seems to be 5 mg. Psychometric analyses demonstrated an improvement in attention, psychomotor performance, mood and affectivity after 3 mg, opposite changes after 10 mg D-12524. Flickerlight fusion, reaction time, after-image and EAS score were determined as well. Data concerning side effects, pulse rate and blood pressure suggested a good tolerance of the drug.

Adult↗
PubMed1994

The costs of colonoscopy in patients with ulcerative pan-colitis in Sweden.

The costs of colonoscopy examinations at a hospital in Sweden were calculated in ten consecutive patients with ulcerative pan-colitis. Since colonoscopy in such patients is incomplete if not followed by microscopic study of the state of the colon mucosa, the costs of both the endoscopic and histological examinations were calculated together. The costs of the material used (disposable items, recycled items and durable items) and the wages for personnel involved (endoscopists, pathologists, nurses, laboratory technicians, secretaries and clerks) were calculated for each colonoscopic and histological examination. The mean cost per complete examination was US$223, which is moderate despite the high personnel costs in Sweden. Since the biopsy material obtained in an endoscopic examination is of value not only for conventional histological study but also for DNA analysis, periodic colonoscopy is still to be recommended in patients with long-standing ulcerative pan-colitis until new methods of cancer detection and prevention become available.

Adult↗
PubMed1994

Circadian sneezing.

Prompted by the observation that a fellow medical student sneezed at about the same time in class every morning, we recorded the time of each of the 118 sneezes she made on 69 days over a 6.5-month period. Analysis of the sneeze times with the goodness-of-fit test revealed a highly nonuniform distribution (p < 0.0001) with a significantly increased probability of sneeze production within a small time interval centered at 8:20 AM. After ruling out the known causes of sneezing, we propose that the subject had a circadian fluctuation in her sneeze threshold independent of any immediate external stimulus. We compare this circadian rhythm to other periodic phenomena such as cyclic esotropia and rapid-cycling bipolar disease as well as to illnesses such as the periodic paralyses in which rapid and reversible changes occur in the neuromuscular system, and we discuss the peculiar circumstances favorable to documenting a circadian sneeze.

Adult↗
PubMed2006

Short term involuntary psychiatric examination of children in Florida.

This study describes the use of emergency mental health services by children over a 4-year period. Analysis of a statewide database revealed 51,861 or 15% of all involuntary examinations were conducted on children. These youth were on average a little over 14 years of age and law enforcement officials initiated the majority of examinations. The majority of examinations were initiated due to the children demonstrating harmful behaviors to themselves or others. One-fifth of the children (21%) experienced more than one examination over the 4-year period. Areas of future research on this topic are discussed. The implications of the nature of examinations and patterns of repeated examinations are discussed.

Adolescent↗
PubMed1992

Immunocytochemical analysis of blood lymphocytes in uveitis.

We studied the surface expression of activation markers IL2-R, HLA-DR and CD45-RO on peripheral T-lymphocytes in two groups of patients (n = 26) with idiopathic uveoretinitis, compared with controls. Thirteen patients were analysed by alkaline phosphatase anti-alkaline phosphatase (APAAP) immunocytochemistry, which demonstrated a significant rise in expression of HLA-DR and IL2-R surface markers. Flow cytometric analysis was performed on a further 13 patients, which confirmed a significant rise in IL2-R expression in uveitis patients. Within this group systemic activation was confined to patients with idiopathic retinal vasculitis. Dual flow cytometry confirmed a CD4+,IL2--R+ T--lymphocyte phenotype. A further 4 patients with retinal vasculitis who had been treated with cyclosporin A demonstrated a 32% reduction in IL2-R expression over a 3-month period. Analysis of CD45-RO and CD5+ cells was found to be uninformative in this study. We have demonstrated activated peripheral lymphocytes in patients predominantly with retinal vasculitis, the significance of which is discussed.

Biomarkers↗