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D Heller

Publications and source records attributed to D Heller.

At least 19 recordsLinked to original sources
PubMed2006

Use of tissue-fluid correlations to estimate gentamicin residues in kidney tissue of Holstein steers.

Gentamicin continues to be one of the most effective antibiotics for the treatment of gram-negative infections. Greater than 90% of the drug is rapidly eliminated from the body in <2 days, however, a small residue remains bound to the kidney cortex tissue for many months. In beef steers, the gentamicin residue is unacceptable and its presence is monitored by the FAST (Fast Antimicrobial Screen Test) applied to the kidney at the time of slaughter. The sensitivity of the FAST to gentamicin in the kidney cortex is reported to be 100 ng/g, therefore, this level of gentamicin defines the acceptable limit of gentamicin drug residue in the bovine kidney. In the present study, three doses of 4 mg/kg gentamicin was administered intramuscularly to eight steers. Gentamicin was allowed to deplete from the kidneys for a range of times from 7 to 10 months. At slaughter the level of gentamicin in the kidney cortex varied from 91 to 193 ng/g, but a total of 160 FAST tests performed on the kidneys were negative. Blood and urine samples were collected at varying times following the last dose of gentamicin. Kidney tissue samples were collected by laparoscopic surgery in the live steers as well as the final sample obtained at slaughter. Plasma levels of gentamicin declined rapidly to nondetectable within 3 days, while measurable urine persisted for 75 days before the concentration of gentamicin declined to levels too low to quantitate by the available liquid chromatography tandem mass spectrometry (LC/MS/MS) technique. An estimated correlation between an extrapolation of urine gentamicin concentration to the corresponding kidney tissue sample suggests a urine to kidney tissue relationship of 1:100. A test system sufficiently sensitive to a urine gentamicin concentration of 1 ng/mL will correlate with the estimated 100 ng/g gentamicin limit of the FAST applied to the fresh kidney of the recently slaughtered bovine.

Animals↗
PubMed2006

Bovine kidney tissue/biological fluid correlation for penicillin.

Penicillin is one of the most commonly misused drugs in steers and dairy cows. In the US, at slaughter the tolerance is 50 ng/g in kidney and other edible tissues. If the tolerance is exceeded, the carcass may not be used for human food. A preslaughter test for penicillin in an easily accessible biological fluid is needed to predict if the concentration of penicillin is below tolerance in the kidney before the bovine is slaughtered. In this study, 12 steers were injected three times with the approved dose (7000 IU) of penicillin at 12-h intervals. Blood and urine samples were collected at intervals after the final dose of penicillin. At each sampling point, one kidney biopsy sample was collected by laparoscopic surgery in the live animal. Another kidney sample was collected at slaughter. Correlations between plasma and kidney concentrations and between urine and kidney concentrations were determined. These correlations predict with 95% confidence that 99% of the animals will have kidney tissue below penicillin tolerance when the plasma concentration of penicillin is below 0.4 ng/mL and/or the urine penicillin concentration is below 140 ng/mL.

Abattoirs↗
PubMed2005

Placental diagnostic criteria and clinical correlation--a workshop report.

Placental pathology is a valuable link explaining how underlying pregnancy risk factors result in adverse pregnancy outcome. This potentially useful information is currently underutilized due to a general lack of rigor in placental diagnosis. This lack of rigor is in large part due to a failure to appreciate the importance of the information provided and hence to demand accurate and clinically responsive reporting. This workshop reviewed the results of a recent initiative by the Perinatal Section of the Society for Pediatric Pathology to systematize and validate diagnostic schema for the description of lesions related to three important pathologic processes: amniotic fluid infection, maternal vascular underperfusion, and fetal vascular obstruction. This was followed by presentation of three studies correlating these pathologic processes with the following clinical outcomes: complications of prematurity, fetal growth restriction, and neurodisability following term delivery.

Female↗
PubMed2005

Child patients in a field hospital during the 2003 Gulf conflict.

During the 2003 conflict in the Gulf, 202 Field Hospital provided the initial Role 3 medical support when hostilities began on 20th March. The first child casualty arrived two days later and over the next four weeks there were 24 admissions of patients aged 15 years or less, amounting to 2% of the total admissions but constituting 19% of ITU admissions. There were 49 operations on children out of a total of 352 theatre cases. The small number of children treated had a disproportionate impact on the functioning of the field hospital. Planned provision for such patients could reduce this impact and should include suitable equipment and specialist staff.

Adolescent↗
PubMed2004

Fetal vasculitis in preterm newborns: interrelationships, modifiers, and antecedents.

Histologic expressions of the fetal inflammatory response predict preterm delivery and neonatal disorders. We examined 1146 placentas in the Developmental Epidemiology Network data set for histologic evidence of membrane inflammation (subchorionitis, chorionitis, and chorioamnionitis) and fetal vasculitis (acute umbilical vasculitis or chorionic vasculitis). Our main findings are that (1) in the presence of membrane inflammation, fetal vasculitis is common, (2) duration of membrane rupture and gestational age appear to modify the risk of fetal vasculitis, (3) this risk modification differs for the different components of fetal vasculitis, i.e. umbilical and chorionic vasculitis, and (4) antecedents can be identified that appear to increase or decrease the risk of fetal vasculitis among births with membrane inflammation. We conclude that fetal vasculitis, the morphologic component of the fetal inflammatory response, might not be a homogeneous entity and deserves further study.

Adult↗
PubMed2004

Antimicrobial use in paediatric wards of teaching hospitals in Bangladesh.

To ascertain the pattern of antimicrobial use and to assess its appropriateness a 4-month prospective study was conducted from January through April 1998 in paediatric wards of five selected medical college hospitals in Bangladesh. The hospitals were selected by simple random technique. Every patient in the paediatric wards of the selected hospitals who was being treated with antimicrobials during the data collection period was considered for the study. The treatment charts of 2171 admitted paediatric patients were reviewed. Pneumonia and diarrhoea were the two most common infectious diseases among them. The most commonly used antimicrobials were ampicillin, gentamicin, amoxicillin, cloxacillin and ceftriaxone. The majority of the admitted paediatric patients (56.1%) included in this study received two or more antimicrobials in combination for their treatment. The percentages of appropriate antimicrobial treatment of pneumonia, and diarrhoea were 57.1% and 67.8% respectively across the hospitals. The evident of high percentages of inappropriate antimicrobial treatment for the most common infectious diseases suggested the need for intervention to improve antimicrobial use in hospitals.

Adolescent↗
PubMed2001

Sex chromosome mosaicism in gonads of a fetus with cystic hygroma and deletion of the short arm of Y chromosome including loss of SRY.

The SRY gene on the short arm of the Y chromosome is necessary for male development. Without SRY, patients with 46,XY karyotype develop as females, fail to achieve normal puberty and have dysgenic gonads and a high incidence of gonadoblastoma. Here we report a female fetus, aborted at 17 weeks of pregnancy, with a non-mosaic 46,X,del(Y)(p11.2).ish del(Y)(SRY-) karyotype diagnosed by classical cytogenetics and fluorescence in situ hybridization (FISH). Ovarian tissue was full of oocytes and mitotic figures. FISH studies of ovarian tissues with X and Y centromere probes revealed extensive sex chromosome mosaicism, manifested by loss of the Y chromosome and polysomy of the X chromosome. We propose that X chromosome polysomy is a post-zygotic event that arises to facilitate gonadal differentiation in the absence of all factors necessary for normal gonadal development.

Abortion, Induced↗
PubMed2001

Human papillomavirus typing in HIV-positive women.

OBJECTIVE: Human papillomavirus (HPV) is the major cause of cervical carcinoma and cervical intraepithelial neoplasia worldwide. Certain HPV types have a strong association with and probably a causative role in the pathogenesis of premalignant cervical lesions. Epidemiologic studies in women infected by the human immunodeficiency virus (HIV) have shown an increased incidence of squamous intraepithelial lesions (SILs), which were predominantly high-grade. Six to 30 per cent of women diagnosed with atypical squamous cells of undetermined significance (ASCUS) on a Papanicolaou (Pap) smear harbor SIL in normal screening populations. This study was undertaken to determine the presence of low-and high-risk HPV types in women infected by HIV and to correlate the results to those of the Pap smear. STUDY DESIGN: HPV DNA typing (low- and high-risk) by Digene (Digene Corporation, Gathesburg, MD) hybrid capture methodology was performed on cervical swabs from 209 HIV-positive women. The results of HPV typing were correlated with those of the Pap smear in a retrospective analysis. RESULTS: One hundred and one women (48%) tested positive for HPV subtypes by DNA typing by the hybrid capture method. Of these, 64 patients (63%) had Pap smears which were read as being normal, having benign cellular changes, or having ASCUS (favor reactive process). Of these, 19 patients tested positive for both high-risk and low-risk subtypes, 32 patients tested positive only for high-risk subtypes, and 13 patients tested positive only for low-risk subtypes. CONCLUSION: HPV subtyping identifies a significant group of HIV-positive women who are at risk for developing cervical intraepithelial neoplasia, although they may not show significant abnormalities on their Pap smears.

DNA, Viral↗
PubMed2001

[Estimating the supply of medical specialists in Colombia by using the capture-recapture method].

OBJECTIVE: Given that it is not known how many medical doctors there are in Colombia and that, without that datum, studies of demand are simply theoretical exercises, we proposed to estimate the supply of 12 medical specialties in Colombia, using the capture-recapture technique, which was developed by zoologists to estimate wild-animal populations. METHODS: Three lists, or "captures," were used: 1) university degrees obtained abroad and graduates of postgraduate programs in Colombia, 2) members of medical societies, and 3) specialists in the principal health care enterprises. To estimate the total population we used the CAPTURE software program. RESULTS: A total of 24,910 records were obtained: 8,397 from the university records, 6,561 from the scientific societies, and 9,952 from the health care businesses. More than half of the physicians have entered the labor market during the last decade. The estimated number of physicians (with the 95% confidence interval) for each specialty was: anesthesiology, 1,753 (1,727 to 1,789); cardiology, 607 (598 to 624); dermatology, 517 (514 to 525); obstetrics and gynecology, 2,338 (2,290 to 2,400); pulmonary disease, 304 (297 to 320); neurosurgery, 324 (319 to 334); neurology, 321 (296 to 369); ophthalmology, 1,049 (1,042 to 1,061); orthopedics, 1,217 (1,212 to 1,227); otolaryngology, 634 (628 to 645); psychiatry, 855 (838 to 879); and urology, 452 (452 to 458). CONCLUSIONS: The capture-recapture technique is useful in the study of human resources. In Colombia the number of specialists doubled in less than a decade. There are specialties that are already oversupplied, such as neurosurgery. All the other specialties show growth rates that indicate a future over-supply for the health care system.

Colombia↗
PubMed2001

Visual search for dimensionally redundant pop-out targets: evidence for parallel-coactive processing of dimensions.

In two visual search experiments, the detection of singleton feature targets redundantly defined on multiple dimensions was investigated. Targets differed from the distractors in orientation, color, or both (redundant targets). In Experiment 1, the various target types were presented either in separate blocks or in random order within blocks. Reaction times to redundant targets significantly violated the race model inequality (Miller, 1982), but only when there was constancy of the target-defining dimension(s) within trial blocks. In Experiment 2, there was dimensional variability within blocks. Consistent with Experiment 1, constancy of the target-defining dimension(s), but this time across successive trials (rather than within blocks), was critical for observing violations of the race model inequality. These results provide evidence for parallel-coactive processing of multiple dimensions, consistent with the dimension-weighting account of Müller, Heller, and Ziegler (1995).

Adolescent↗
PubMed2001

Leiomyosarcoma after uterine artery embolization. A case report.

BACKGROUND: Hysterectomy is the most common treatment for relieving symptoms attributable to uterine leiomyomas; however, alternatives to hysterectomy are becoming increasingly available. Uterine artery embolization is being used more frequently in this clinical setting. CASE: A leiomyosarcoma was diagnosed incidentally in a 51-year-old, nulliparous woman who underwent uterine artery embolization for symptomatic leiomyomata and subsequent total abdominal hysterectomy/bilateral salpingo-oophorectomy due to unsatisfactory results of the embolization procedure. CONCLUSION: While the occurrence of preoperatively undiagnosed uterine leiomyosarcomas among patients undergoing hysterectomies has been reported, there are no reports of unsuspected leiomyosarcomas after uterine artery embolization. Criteria for selection of patients for the procedure should consider the possibility of leiomyosarcoma. With the increasing popularity of uterine artery embolization, cases like this are likely to be encountered in the future.

Arteries↗