Rapid identification of laboratory contamination with Mycobacterium tuberculosis using variable number tandem repeat analysis

Compared with solid media, broth-based mycobacterial culture systems have increased sensitivity but also have higher false-positive rates due to cross-contamination. Systematic strain typing is rarely undertaken because the techniques are technically demanding and the data are difficult to organize. Variable number tandem repeat (VNTR) analysis by PCR is rapid and reproducible. The digital profile is easily manipulated in a database. We undertook a retrospective study of Mycobacterium tuberculosis isolates collected over an 18-month period following the introduction of the BACTEC MGIT 960 system. VNTR allele profiles were determined with early positive broth cultures and entered into a database with the specimen processing date and other specimen data. We found 36 distinct VNTR profiles in cultures from 144 patients. Three common VNTR profiles accounted for 45% of true-positive cases. By combining VNTR results with specimen data, we identified nine cross-contamination incidents, six of which were previously unsuspected. These nine incidents resulted in 34 false-positive cultures for 29 patients. False-positive cultures were identified for three patients who had previously been culture positive for tuberculosis and were receiving treatment. Identification of cross-contamination incidents requires careful documentation of specimen data and good communication between clinical and laboratory staff. Automated broth culture systems should be supplemented with molecular analysis to identify cross-contamination events. VNTR analysis is reproducible and provides timely results when applied to early positive broth cultures. This method should ensure that patients are not placed on unnecessary tuberculosis therapy or that cases are not falsely identified as treatment failures. In addition, areas where existing procedures may be improved can be identified.

Anger, harassment, and cardiovascular reactivity among Chinese and Indian men in Singapore

OBJECTIVE

This experiment examined psychological and cardiovascular responses to experimental harassment among Chinese and Indian men in Singapore who differed in levels of dispositional anger.

METHODS

Eighty-four Chinese and Indian men participated in a laboratory experiment on cardiovascular reactivity in which mood was rated and heart rate and blood pressure were measured during computer tasks in which they were either harassed or allowed to complete the tasks without interruption.

RESULTS

Comparison of systolic reactivity to harassment and nonharassment indicated, as expected, that reactivity was greater after harassment. Furthermore, a significant race by dispositional anger by harassment effect was obtained for systolic reactivity that indicated different patterns of reactivity for Chinese and Indian participants. In the absence of harassment, Chinese participants showed low systolic reactivity regardless of their level of dispositional anger, whereas systolic reactivity increased as a function of dispositional anger when they were harassed. For Indians, however, systolic reactivity was a positive function of dispositional anger both when they were harassed and not harassed.

CONCLUSIONS

These results suggest stronger cardiovascular reactivity to stress among Indian than among Chinese men. This seems to be particularly true for Indians high in dispositional anger.

Competency development in public health leadership

The professional development of public health leaders requires competency-based instruction to increase their ability to address complex and changing demands for critical services. This article reviews the development of the Leadership Competency Framework by the National Public Health Leadership Development Network and discusses its significance. After reviewing pertinent literature and existing practice-based competency frameworks, network members developed the framework through sequential use of workgroup assignments and nominal group process. The framework is being used by network members to develop and refine program competency lists and content; to compare programs; to develop needs assessments, baseline measures, and performance standards; and to evaluate educational outcomes. It is a working document, to be continually refined and evaluated to ensure its continued relevance to performance in practice. Understanding both the applications and the limits of competency frameworks is important in individual, program, and organizational assessment. Benefits of using defined competencies in designing leadership programs include the integrated and sustained development of leadership capacity and the use of technology for increased access and quality control.

Transforming growth factor-alpha-mediated growth pathways in human gastro-intestinal cell lines in relation to the gastrin autocrine pathway

Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) increase transcription of the gastrin gene, and the gastrin peptide may be phosphorylated by EGF-stimulated tyrosine kinase. Our aims were to compare EGF/TGF-alpha interactions in 2 human gastro-intestinal cell lines: MGLVA1, with a strong gastrin autocrine pathway, and C170HM2, with a weak pathway. Both cell lines expressed the TGF-alpha gene. MGLVA1 expressed TGF-alpha protein as determined by immuno-cytochemistry, which was absent in C170HM2. Both cell lines expressed the same level of EGF receptors, as assessed by flow cytometry; however, MGLVA1 did not have enhanced in vitro proliferation in response to EGF or TGF-alpha, unlike C170HM2. The basal growth of MGLVA1 was inhibited by anti-sera against TGF-alpha, the EGF receptor and G17. C170HM2 was not inhibited by any of the anti-sera. Neutralisation of TGF-alpha resulted in undetectable cell-associated progastrin levels in MGLVA1 (untreated had 391.7 fmol/5 x 10(6) cells). The progastrin level of C170HM2 remained unaffected. Tyrosine kinase activity, as assessed by phosphopeptide concentration, of unstimulated MGLVA1 was 2.6 times higher than that of C170HM2 in the cell membrane fraction (0.097 compared to 0.037 microg/mg protein, p < 0.001) and 4.8 times higher in the cytosolic fraction (0.269 compared to 0.056 microg/mg protein, p < 0.05). Following treatment with EGF, the phosphopeptide concentration increased in both the membrane and cytosolic fractions of both cell lines. Tyrphostin B42, which inhibits autophosphorylation of the EGF receptor, inhibited the basal growth of MGLVA1 (IC(50) 1.3 microM) and C170HM2 (9.5 microM, p < 0.05 from MGLVA1). Herbimycin, which inhibits pp60(c-src) kinase, reduced the basal growth of MGLVA1 (0.67 microM) but not C170HM2. Immunofluorescence studies confirmed the presence of tyrosine-phosphorylated proteins and pp60(c-src) within the cytoplasm of unstimulated MGLVA1 cells. There was no specific immunofluorescence for either parameter in C170HM2 cells until after treatment with EGF.

What are the attitudes of general practitioners towards research?

There is an urgent need for high quality primary care research to provide a firm scientific basis for a primary care-led National Health Service; however, relatively little is known about general practitioners' (GPs') stated practices and attitudes towards research. This cross-sectional questionnaire study documents the attitudes and stated practices of general practitioners towards undertaking and using research. Virtually all 249 (90%) GP responders felt that primary care research was important, while majorities expressed interest in research (61%), using research to directly influence practice (68%), and an interest in undertaking future research (53%). Perceived priorities for future primary care research are chronic illness, primary care organisation, and patient behaviour.

Psychological adjustment to familial genetic risk assessment: differences in two longitudinal samples

Heritable cancer risk assessment is an increasingly common method of deriving valuable information relevant to deciding on appropriate screening regimens and preventive treatments. Assessments of heritable risk typically include familial-genetic evaluation, where analyses relate family pedigree to cancer risk, and DNA testing, where analyses indicate genetic mutations associated with cancer risk (e.g., BRCA1/BRCA2 mutations) or their absence. In this paper we report on the psychological responses of women given familial-genetic evaluations for ovarian cancer risk. The baseline and 6 to 12 follow-up assessments of an initial clinic-attending cohort of 65 women are compared with the baseline and 9 to 12 follow-up assessments of a second clinic-attending cohort of 60 women. Sizeable differences were found in the prevalence of clinically significant depression in these two physician or self-referred populations, as assessed by the Center for Epidemiological Studies Depression scale and in the mean scores. Hypotheses accounting for these differences are discussed.

Regulation of vascular endothelial growth factor-dependent retinal neovascularization by insulin-like growth factor-1 receptor

Although insulin-like growth factor 1 (IGF-1) has been associated with retinopathy, proof of a direct relationship has been lacking. Here we show that an IGF-1 receptor antagonist suppresses retinal neovascularization in vivo, and infer that interactions between IGF-1 and the IGF-1 receptor are necessary for induction of maximal neovascularization by vascular endothelial growth factor (VEGF). IGF-1 receptor regulation of VEGF action is mediated at least in part through control of VEGF activation of p44/42 mitogen-activated protein kinase, establishing a hierarchical relationship between IGF-1 and VEGF receptors. These findings establish an essential role for IGF-1 in angiogenesis and demonstrate a new target for control of retinopathy. They also explain why diabetic retinopathy initially increases with the onset of insulin treatment. IGF-1 levels, low in untreated diabetes, rise with insulin therapy, permitting VEGF-induced retinopathy.

Exploring the scope for advocacy by paediatricians

AIMS

To ascertain the type and extent of problems requiring advocacy in paediatrics. To develop an approach for analysing problems according to their root causes and the level of society at which advocacy is needed.

METHODS

Nine paediatricians kept detailed clinical diaries for two weeks to identify problems. Classifications were developed to categorise problems by cause and the level of society at which they needed to be addressed. The press was surveyed for one week for childhood issues attracting media attention.

RESULTS

60 problems requiring advocacy were identified. Root causes included failures within agencies, between agencies, and inadequate provision. In addition to advocacy required individually, "political" action was needed at the community level (16 issues), city level (16 issues), and nationally (15 issues). 103 articles were found in the press, these did not relate closely to issues identified by clinicians.

CONCLUSIONS

Many opportunities for advocacy arise in the course of daily work. A systematic way of analysing them has been developed for use in planning action. To optimise the health and health care of children, there is a need to train and support paediatricians in advocacy work for local as well as national issues. Ten issues were identified that might be prioritised by paediatricians working on an agenda for action.

In vivo gene expression profile analysis of human breast cancer progression

The development and use of molecular-based therapy for breast cancer and other human malignancies will require a detailed molecular genetic analysis of patient tissues. The recent development of laser capture microdissection and high density cDNA arrays now provides a unique opportunity to generate gene expression profiles of cells from various stages of tumor progression as it occurs in the actual neoplastic tissue milieu. We report the combined use of laser capture microdissection and high-throughput cDNA microarrays to monitor in vivo gene expression levels in purified normal, invasive, and metastatic breast cell populations from a single patient. These in vivo gene expression profiles were verified by real-time quantitative PCR and immunohistochemistry. The combined use of laser capture microdissection and cDNA microarray analysis provides a powerful new approach to elucidate the in vivo molecular events surrounding the development and progression of breast cancer and is generally applicable to the study of malignancy.

Improvement of tension-type headache when treating wrinkles with botulinum toxin A injections

Botulinum toxin A has been used to treat a spectrum of neuromuscular diseases. In recent years, it has become an accepted treatment for dynamic facial wrinkles. Following treatment of glabella and forehead wrinkles with botulinum toxin A, 9 of 134 patients coincidentally reported improvement of tension-type headache. We have retrospectively studied this group of patients in whom improvement of facial wrinkles closely paralleled improvement of tension-type headache. This observation suggests a role for muscle action in tension-type headache and a novel treatment.

Attributional style and depression in schizophrenia

OBJECTIVES

The literature implies that negative attributional style is a psychological correlate of depression. Recent evidence suggests that negative attributional style may be specific to depression. This study examines the association between level of depression and negative attributional style in a sample of individuals with schizophrenia.

METHOD

One hundred and thirteen inpatients with schizophrenia were assessed with the Calgary Depression Scale for Schizophrenia and the Attributional Style Questionnaire.

RESULTS

Attributions of negative events to internal and to global causes were significantly associated with depressive symptoms. Only the global dimension was significantly associated with positive symptoms. No attributional dimensions were significantly associated with negative symptoms.

CONCLUSIONS

These results are consistent with the idea that negative attributional style may be specific to depression and not a general characteristic of psychopathology.

A longitudinal study of psychological adjustment to familial genetic risk assessment for ovarian cancer

OBJECTIVES

To evaluate the psychological adjustment of women during initial genetic ovarian cancer risk assessment and at clinic follow-up, 6-12 months later.

METHODS

Sixty-five subjects were assessed with the Centre for Epidemiological Studies Depression Scale (CESD), Spielberger's State Anxiety Inventory, and an 18-item, investigator-designed questionnaire yielding self-report on screening responses, worry about increased risk, identification of cancer-related deaths in relatives, worry about future cancer risks of daughters, alteration of future plans as a result of ovarian cancer risk, etc.

RESULTS

Thirty-three percent of subjects had CESD scores above the established cutoff for depression at baseline and 38% had scores above cutoff at follow-up. Sixteen percent of subjects had state scores on the State-Trait Anxiety Inventory higher than 1 standard deviation above average (norm) at baseline, while only 6% had scores higher than 1 SD above average at follow-up.

CONCLUSION

To identify factors associated with self-reported depression at follow-up, a series of demographic and self-reported variables (e.g., presence of identified problems in family, impact of genetic risk information, concern for daughter in the future) were entered in a multiple regression analysis with the CESD follow-up score as the dependent variable. Only one predictor accounted for a significant amount of variance in depression scores. Concern for daughter's risk in the future was associated with higher depression scores at follow-up (R = 0.33, P<0.02, R(2) = 11%).

The localization and expression of the renin-angiotensin system in the human placenta throughout pregnancy

All the components of the renin-angiotensin system (RAS), including the AT(1)receptor, have previously been shown to be present in the human term placenta. However, the presence of the RAS components has not been fully investigated in the human placenta throughout pregnancy. The aim of this study was to examine the localization of the angiotensin receptors AT(1)and AT(2)using immunocytochemistry and the expression of prorenin, angiotensinogen and the AT(1)and AT(2)receptor mRNA using RT-PCR in the human placenta in the first, second and third trimesters of pregnancy. Localization of the AT(1)receptor was shown throughout gestation in the syncytiotrophoblast, cytotrophoblast, Hofbauer cells and the fetal vascular endothelium. Expression of mRNA for prorenin, angiotensinogen and the AT(1)receptor was shown in the placenta throughout gestation. However, localization or mRNA expression of the AT(2)receptor was not detected in any of the placental samples studied. These results clearly show the expression of a majority of the components of the RAS in the placenta from early gestation onwards. Therefore, these results suggest that the RAS may have a role in the human placenta throughout gestation.

Antagonist activities of mecamylamine and nicotine show reciprocal dependence on beta subunit sequence in the second transmembrane domain

We show that a portion of the TM2 domain regulates the sensitivity of beta subunit-containing rat neuronal nicotinic AChR to the ganglionic blocker mecamylamine, such that the substitution of 4 amino acids of the muscle beta subunit sequence into the neuronal beta4 sequence decreases the potency of mecamylamine by a factor of 200 and eliminates any long-term effects of this drug on receptor function. The same exchange of sequence that decreases inhibition by mecamylamine produces a comparable potentiation of long-term inhibition by nicotine. Inhibition by mecamylamine is voltage-dependent, suggesting a direct interaction of mecamylamine with sequence elements within the membrane field. We have previously shown that sensitivity to TMP (tetramethylpiperidine) inhibitors is controlled by the same sequence elements that determine mecamylamine sensitivity. However, inhibition by bis-TMP compounds is independent of voltage. Our experiments did not show any influence of voltage on the inhibition of chimeric receptors by nicotine, suggesting that the inhibitory effects of nicotine are mediated by binding to a site outside the membrane's electric field. An analysis of point mutations indicates that the residues at the 6' position within the beta subunit TM2 domain may be important for determining the effects of both mecamylamine and nicotine in a reciprocal manner. Single mutations at the 10' position are not sufficient to produce effects, but 6' 10' double mutants show more effect than do the 6' single mutants.

Selective sparing of verb naming in a case of severe Alzheimer's disease

A patient with severe Alzheimer's disease (AD) presented with a severe impairment in naming nouns but selective sparing of the naming of verbs. Her impairment in naming nouns was presented across a wide range of categories investigated. To our knowledge, this is the first case documenting the selective preservation of verb naming in a patient with AD. The implications for the notion of an intrinsic vulnerability of verb naming in AD and for the current knowledge of anatomical correlates of noun/verb processing are discussed.

Fractionation of visual memory: evidence from a case with multiple neurodevelopmental impairments

It is known that the adult visual memory system is fractionable into functionally independent cognitive subsystems, selectively susceptible to brain damage. However, it is unclear whether these cognitive subsystems can fractionate developmentally. The present study describes an investigation of visual memory of a patient (PE) with multiple developmental disorders. PE was congenitally deaf, had Gilles de la Tourette syndrome and autism, with non-verbal ability in the normal range. The patient presented with a recognition memory impairment for unknown human faces. This contrasted with his superior recognition memory for unknown buildings, landscapes and outdoor scenes. PE's memory impairment for faces could not be explained by a general deficit in face processing. Interestingly, PE also showed a recognition memory impairment for animals. These findings indicate that different domains of the visual memory system can be fractionated developmentally. In particular, it demonstrates that topographical memory can develop independently from other aspects of visual memory.

Placental failure in mice lacking the homeobox gene Dlx3

Dlx3 is a homeodomain transcription factor and a member of the vertebrate Distal-less family. Targeted deletion of the mouse Dlx3 gene results in embryonic death between day 9.5 and day 10 because of placental defects that alter the development of the labyrinthine layer. In situ hybridization reveals that the Dlx3 gene is initially expressed in ectoplacental cone cells and chorionic plate, and later in the labyrinthine trophoblast of the chorioallantoic placenta, where major defects are observed in the Dlx3 -/- embryos. The expression of structural genes, such as 4311 and PL-1, which were used as markers to follow the fate of different derivatives of the placenta, was not affected in the Dlx3-null embryos. However, by day 10.5 of development, expression of the paired-like homeodomain gene Esx1 was strongly down-regulated in affected placenta tissue, suggesting that Dlx3 is required for the maintenance of Esx1 expression, normal placental morphogenesis, and embryonic survival.

Medication-induced headache: overview and systematic review of therapeutic approaches

OBJECTIVE

To review medication-induced headache (MIH) through a systematic evaluation of the literature regarding the pharmacologic management of this condition.

METHODOLOGY

To identify and evaluate all pharmacologic interventions for MIH, we conducted a qualitative systematic review of the English-language literature from 1966 to June 1998 using MEDLINE. The following search terms were used: chronic daily headache, transformed migraine, analgesic withdrawal headache, analgesic rebound headache, drug-associated headache, medication-induced headache, detoxification, and dihydroergotamine. In addition, a review of the references from relevant literature was also conducted to collect reports not identified in the MEDLINE search.

RESULTS

Numerous therapies for acute management of MIH have been evaluated, although no rigorously conducted clinical trials were identified. Therapies evaluated include abrupt withdrawal of analgesics, initiation of dihydroergotamine, nonsteroidal antiinflammatory agents, methylergonovine, dihydroergotamine, sumatriptan, amitriptyline, dexamethasone, piracetam, prothipendyl, and valproate. Epidemiology, diagnosis, clinical features, pathophysiology, and long-term prognosis of therapy are discussed and therapeutic guidelines are offered.

CONCLUSIONS

MIH is an underrecognized and difficult condition affecting headache-prone patients. The published literature concerning treatment of patients with MIH is scant and of poor quality, making it difficult for clinicians to decide on appropriate therapy. Recognition and treatment of MIH may lead to a long-term improvement in headache relief for many patients. It appears that complete withdrawal of the medications being overused is required for favorable long-term results.

Cardiopulmonary bypass with danaparoid sodium and ancrod in heparin-induced thrombocytopenia

Heparin is the standard anticoagulant for patients undergoing cardiopulmonary bypass. There are some patients for whom heparin is unsuitable and ancrod (a defibrinogenating enzyme) has been used as an alternative. We present a patient with heparin-induced thrombocytopenia in whom treatment ancrod was ineffective. The addition of danaparoid sodium (a heparinoid) allowed safe cardiopulmonary bypass. We discuss the reasons for this and suggest that the combination of ancrod and danaparoid sodium is a logical one in such cases.

Guidelines for the nonpharmacologic management of migraine in clinical practice. Canadian Headache Society

OBJECTIVE

To provide physicians and allied health care professionals with guidelines for the nonpharmacologic management of migraine in clinical practice.

OPTIONS

The full range and quality of nonpharmacologic therapies available for the management of migraine.

OUTCOMES

Improvement in the nonpharmacologic management of migraine. EVIDENCE AND VALUES: The creation of the guidelines followed a needs assessment by members of the Canadian Headache Society and included a statement of objectives; development of guidelines by multidisciplinary working groups using information from literature reviews and other resources; comparison of alternative clinical pathways and description of how published data were analysed; definition of the level of evidence for data in each case; evaluation and revision of the guidelines at a consensus conference held in Ottawa on Oct. 27-29, 1995; redrafting and insertion of tables showing key variables and data from various studies and tables of data with recommendations; and reassessment by all conference participants.

BENEFITS, HARMS AND COSTS

Augmentation of the use of nonpharmacologic therapies for the acute and prophylactic management of migraine is likely to lead to substantial benefits in both human and economic terms.

RECOMMENDATIONS

Both the avoidance of migraine trigger factors and the use of nonpharmacologic therapies have a part to play in overall migraine management.

VALIDATION

The guidelines are based on consensus of Canadian experts in neurology, emergency medicine, psychiatry, psychology and family medicine, and consumers. Previous guidelines did not exist. Field testing of the guidelines is in progress.

Effects of melatonin implants in pony mares. 2. Long-term effects

The effects of melatonin implant treatment over a 4 wk period at the summer solstice on the transition into and out of the following anovulatory season were evaluated in ovary-intact and ovariectomized mares. Melatonin implants tended to delay the timing of the final ovulation of the breeding season (P = 0.0797) in the ovary-intact mares. Although the decline in LH secretion associated with the end of the breeding season was parallel between treatments and ovarian statuses, the rate of LH secretion, as expressed by its mathematical accumulation, was lower in ovariectomized, melatonin-treated mares than in ovariectomized, control mares suggesting that melatonin administration advanced the offset of the breeding season in ovariectomized mares (P = 0.0001). The first ovulation of the subsequent breeding season was significantly delayed in the melatonin-treated mares as compared with that of control mares (P = 0.0031). During reproductive recrudescence, the time of the onset of the increase in LH secretion was similar among all 4 groups but the patterns of LH secretion were different for each treatment and ovarian status combination (P = 0.0112). Mares with melatonin implants had a slower rate of increase in LH secretion than control mares (P = 0.0001), and ovariectomized mares had a faster rate of LH increase than intact mares (P = 0.0001). These results suggest that melatonin implants during the summer solstice can alter the annual reproductive rhythm in mares and support the concept that endocrine patterns of reproductive recrudescence are not entirely independent of the ovary.

Effects of melatonin implants in pony mares. 1. Acute effects

The effects of melatonin implant treatment over a four week period on LH, estradiol (E2) and progesterone (P4) secretion during the breeding season were studied in ovary-intact and ovariectomized pony mares. Mares with melatonin implants had significantly higher daytime melatonin concentrations than mares with sharm implants (P = 0.0065). In ovariectomized mares, LH secretion did not differ between mares with melatonin and sham implants. In ovary-intact mares, melatonin implants altered the pattern of LH secretion (P = 0.0023) in such a way that an increase in LH secretion was observed during the periovulatory period. Estradiol and P4 secretion were unaffected by melatonin implants. These results suggest that constant administration of melatonin may enhance the secretion of LH during the periovulatory surge but does not adversely affect E2, P4 or basal LH secretion in mares during the breeding season.