Staphylococcus lugdunensis endocarditis

A case of Staphylococcus lugdunensis endocarditis is presented with low back pain suggesting a secondary bone focus of infection. An umbilical skin lesion may have been an additional embolic phenomenon. The case highlights the aggressive nature of S lugdenensis endocarditis compared with other coagulase negative staphylococci and its association with native heart valves. In addition the importance of full identification of coagulase negative staphylococci isolated from patient samples in a case of suspected S lugdenensis infection is emphasised. Antibiotic treatment may be insufficient alone in the treatment of S lugdenensis endocarditis and early recourse to surgical intervention and valve replacement should therefore be considered.

Caveolin-1 expression sensitizes fibroblastic and epithelial cells to apoptotic stimulation

The potential role of caveolin-1 in apoptosis remains controversial. Here, we investigate whether caveolin-1 expression is proapoptotic or antiapoptotic using a well-defined antisense approach. We show that NIH/3T3 cells harboring antisense caveolin-1 are resistant to staurosporine-induced apoptosis, as assessed using cell morphology, DNA content, caspase 3 activation, and focal adhesion kinase cleavage. Importantly, sensitivity to apoptosis is recovered when caveolin-1 levels are restored. Conversely, recombinant stable expression of caveolin-1 in T24 bladder carcinoma cells sensitizes these cells to caspase 3 activation. Consistent with the observations using NIH/3T3 cells, downregulation of caveolin-1 in T24 cells substantially diminishes caspase 3-like activity. Loss of sensitivity to apoptotic stimulation is recovered by inhibition of the phosphatidylinositol 3-kinase pathway using LY-294002, suggesting a possible mechanism for the sensitizing effect of caveolin-1. Thus our results suggest that caveolin-1 may act as a coupling or sensitizing factor in signaling apoptotic cell death in both fibroblastic (NIH/3T3) and epithelial (T24) cells.

Lansoprazole treatment of patients with chronic idiopathic laryngitis: a placebo-controlled trial

OBJECTIVE

Previous uncontrolled studies suggested a therapeutic benefit for treating gastroesophageal reflux disease (GERD) among patients with laryngitis. The present study is the first randomized, placebo-controlled, double-blind study of gastric acid suppression among patients with laryngitis in the United States.

METHODS

Patients diagnosed with idiopathic chronic laryngitis were randomized to receive either lansoprazole 30 mg p.o. b.i.d. or a matching placebo for 3 months. Before randomization, all patients underwent upper endoscopy, dual probe ambulatory 24-h esophageal pH-metry, and laryngoscopy, as well as completing a symptom questionnaire for GERD and laryngitis. The primary outcome of treatment was the complete resolution of laryngeal symptoms.

RESULTS

A total of 22 patients with symptoms and signs of chronic laryngitis were enrolled, 20 of whom completed the study. At baseline, there were no significant differences between the two groups with regards to GERD symptoms, erosive esophagitis, proximal and distal esophageal pH-metry, or laryngeal signs and symptoms. In an intention-to-treat analysis, six patients in the lansoprazole group (50%) and only one patient (10%) in the placebo group achieved a complete symptomatic response, p = 0.04. Apart from receiving lansoprazole, there were no significant differences between responders and nonresponders in any of baseline esophageal or laryngeal signs and symptoms.

CONCLUSIONS

Empirical treatment with lansoprazole is efficacious in relieving symptoms of laryngitis compared to placebo. Such treatment can be considered as a first-line option in managing patients with idiopathic chronic laryngitis.

Clinical features of patients with acute organophosphate poisoning requiring intensive care

OBJECTIVES

To describe the clinical features of organophosphate poisoning (OPP), to evaluate the Acute Physiology and Chronic Health Evaluation (APACHE) II score as an alternative index for measuring OPP severity, and to assess cholinesterase levels for predicting successful weaning from mechanical ventilation (MV).

DESIGN AND SETTING

Retrospective medical record review in a medical intensive care unit of an acute general hospital.

PATIENTS

Twenty-three adults with OPP between 1995 and 1999. All cases were due to malathion poisoning. Muscarinic features were the predominant clinical manifestations (83%), followed by central nervous system (78%) and nicotinic manifestations (17%).

RESULTS

MV was required by 74% of patients because of bronchial secretions (83%), altered conscious level (78%), pneumonia (78%), and flaccid paralysis (57%). Five patients (22%) had features of intermediate syndrome. ICU mortality was 13% and the mean ICU stay was 9.1 +/- 6.0 days. The mean APACHE II score was 17.4 +/- 7.4 and it correlated with mortality, severity of OPP, length of MV, and cholinesterase level. An APACHE II score of 26 or higher was predictive of mortality, with 95% sensitivity and 100% specificity. Threshold levels of serum and red blood cell cholinesterase for successful weaning from MV were 2,900 U/l and 7,500 U/l, respectively.

CONCLUSIONS

The APACHE II score may be used as an alternative index of severity in patients with OPP; a score of 26 or higher is a good predictor of mortality. Cholinesterase levels are useful in predicting successful weaning of patients from MV.

Functional interaction of human Cdc37 with the androgen receptor but not with the glucocorticoid receptor

Cdc37 is a molecular chaperone closely associated with the folding of protein kinases. Results from studies using a yeast model system showed that it was also important for activation of the human androgen receptor (AR). Based on results from the yeast model system (Fliss, A. E., Fang, Y., Boschelli, F., and Caplan, A. J. (1997) Mol. Biol. Cell 8, 2501-2509), we initiated studies to address whether AR and Cdc37 interact with each other in animal cell systems. Our results show that Cdc37 binds to AR but not to glucocorticoid receptors (GR) synthesized in rabbit reticulocyte lysates. This binding occurs via the ligand-binding domain of the AR in a manner that is partially dependent on Hsp90 and the presence of hormone. Further studies using the yeast system showed that Cdc37 is not interchangeable with Hsp90, suggesting that it functions at a distinct step in the activation pathway. Expression of a dominant negative form of Cdc37 in animal cells down-regulates full-length AR but has very little effect on an AR truncation lacking the ligand-binding domain or full-length GR. These results reveal differences in the mechanisms by which AR and GR become active transcription factors and strengthen the notion that Cdc37 has a wider range of polypeptide clients than was realized previously.

NO as an autocrine mediator in the apoptosis of activated microglial cells: correlation between activation and apoptosis of microglial cells

Abnormal activation of microglial cells has been implicated in various neurodegenerative diseases. Microglial activation needs to be tightly regulated for physiological maintenance and normal functioning of the central nervous system. Potential mechanisms for the down-regulation of activated microglial cells are the deactivation or elimination of activated cells. We hypothesized that the elimination of activated microglial cells by apoptosis is one of the key mechanisms of auto-regulation of activated microglial cells. To test this hypothesis, we utilized BV-2 mouse microglial cells and rat primary microglial cultures exposed to activating agents such as lipopolysaccharide and interferon-gamma, and investigated a possible correlation between apoptosis and activation of these cells. We found that the activation of microglial cells led to apoptotic death, and the activation state of microglial cells inversely correlated with cell viability. We have also demonstrated that: (i) NO was produced by activated microglial cells in a manner dependent on time and dose of activating agents; (ii) inhibition of NO synthesis by iNOS inhibitor blocked the apoptosis of activated microglial cells; (iii) an exogenous NO donor induced apoptosis of microglial cells; and (iv) inhibition of TNFalpha or FasL using neutralizing antibodies did not affect activation-induced apoptosis of microglial cells. These results indicated that activation of microglial cells leads to the production of NO, which in turn acts as the major mediator of cellular apoptosis in an autocrine fashion. Our work suggests the presence of auto-regulatory mechanism for microglial activation, which may have relevance in the pathogenesis of various neurodegenerative diseases possibly resulting from 'over-activation' of microglial cells.

Axotomy alters neurotrophin and neurotrophin receptor mRNAs in the vagus nerve and nodose ganglion of the rat

Neurotrophins and neurotrophin receptors play an important role in survival and growth of injured peripheral nerves. To study the injury-mediated neurotrophic response in autonomic nerves, we investigated changes in mRNA expression of neurotrophins and their receptors in the transected vagus nerve and nodose ganglion. Studies using in situ hybridization histochemistry showed that axotomy of the cervical vagus nerve resulted in increased expression of mRNAs for nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3), and for TrkA, TrkB, and TrkC receptors in non-neuronal cells at both the proximal and distal segments of the transected cervical vagus nerve. Moreover, NGF protein was increased in the distal end, and NT-3 protein was increased in both the proximal and the distal ends of the transected nerve 3 days after axotomy. No change of p75(NTR) mRNA was detected in the transected vagus nerve. The induction of each neurotrophin and Trk receptor mRNA was apparent within 1 day after the axotomy and was sustained at least 14 days. By 45 days after the axotomy, a time when axonal reconnection with target tissue is made (integrity of the nerve-target connection was confirmed by the retrograde transport of FluoroGold from the stomach to vagal cell bodies), the levels of neurotrophin and Trk mRNAs in the vagus nerve declined to pre-axotomy levels. TrkA, TrkC, and p75(NTR) mRNA-containing vagal sensory neurons in the nodose ganglion were reduced in number after cervical vagotomy. Neurotrophin-mRNA-containing neurons were not found in the nodose ganglia from either intact or vagotomized rats. The axotomy-induced up-regulation of neurotrophins and Trk receptors mainly in the non-neuronal cells at or near the site of transection suggests that neurotrophins are involved in the survival and regeneration process of the vagus nerve after injury.

Differences in antigen recognition and cytolytic activity of CD8(+) and CD8(-) T cells that express the same antigen-specific receptor

CD8(+) and CD8(-) T cell lines expressing the same antigen-specific receptor [the 2C T cell receptor (TCR)] were compared for ability to bind soluble peptide-MHC and to lyse target cells. The 2C TCR on CD8(-) cells bound a syngeneic MHC (K(b+))-peptide complex 10-100 times less well than the same TCR on CD8(+) cells, and the CD8(-) 2C cells lysed target cells presenting this complex very poorly. Surprisingly, however, the CD8(-) cells differed little from CD8(+) cells in ability to bind an allogeneic MHC (L(d+))-peptide complex and to lyse target cells presenting this complex. The CD8(+)/CD8(-) difference provided an opportunity to estimate how long TCR engagements with peptide-MHC have to persist to initiate the cytolytic T cell response.

Low back pain: prevalence and risk factors in an industrial setting

OBJECTIVE

To examine various factors associated with low back pain (LBP) in an industrial setting.

METHODS

A cross sectional study was carried out among 1,562 employees of a large utilities corporation in Ontario using a self-administered questionnaire. Abdominal muscle strength was measured using a modified sphygmomanometer. Statistical analysis was carried out with Student's t test, chi-square test, and logistic regression analysis.

RESULTS

Among 1,302 male employees the lifetime and point prevalence of LBP were 60% and 11%, respectively. Low back pain was significantly more prevalent among married employees, with more physically demanding jobs, regular lifting, poor general health, and past major illness. Abdominal muscle weakness was associated with current LBP. The mean time lost from work due to LBP over 5 years was 17 days. Sedentary workers developing LBP were more likely to require hospital admission.

CONCLUSION

This study confirms the high prevalence of LBP in industry and identifies several risk factors.

Transmission of Mycobacterium tuberculosis to a funeral director during routine embalming

Several studies have shown that funeral directors have an increased risk of tuberculosis (TB). Although there is indirect evidence of transmission of TB from cadavers to mortuary workers, there is only one recently documented case in the literature. We report here another case of occupationally acquired TB in a funeral director, which was confirmed by conventional epidemiology and genotyping. This case illustrates the risk of TB transmission to mortuary workers from routine embalming of deceased TB patients with active disease.

Is partnership in A&E feasible?

Partnership in care is frequently discussed within the discipline of children's nursing. There have been few definitions as to its meaning and therefore how it should be applied within the different specialties of children's nursing. This literature review identified a lack of research regarding partnership in care within the Accident and Emergency environment.

Vulnerability to health problems in female informal caregivers of persons with HIV/AIDS and age-related dementias

The health of informal caregivers is often studied from the perspective of caregivers' and care receivers' personal and interpersonal characteristics. This study offers an alternative explanation based on a vulnerable populations framework and considers the role of resource availability to the health status of informal caregivers (n=76). Caregivers in a convenience sample were females of diverse ethnicity and socioeconomic status, and care recipients were diagnosed with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) or age-related dementias (ARD). Personal interviews using structured instruments were conducted with caregivers who were attending outpatient clinics at a public hospital and a VA hospital. Instruments included the Center for Epidemiologic Studies Depression-Scale (CES-D), the Global Health Assessment (GHA), the Activities of Daily Living Scale (ADL), the Memory and Behavior Problems Checklist (MBPC) and items from the Symptom Checklist-90 (SCL-90) measuring anger, anxiety and loneliness. Caregivers were experiencing both physical and mental health problems. Regression analyses were used to examine the relationships among resources available to caregivers, conditions that put caregivers at risk for poorer health, and health status itself. Analyses were conducted for each group of caregivers separately (HIV and ARD) and for the total group, using depressive symptoms and perception of physical health as dependent variables. In caregivers of people with HIV/AIDS (PWHIV), caregiver distress over care recipient symptoms, anxiety and education were related to depressive symptoms. Depressive symptoms, anger and functional status of the PWHIV were related to caregivers' perception of poorer physical health. In caregivers of people with ARD, there were no significant predictors for depressive symptoms or perception of physical health. In the total group of caregivers, lower income and more anger were related to depressive symptom score. When perception of physical health was the dependent variable, minority ethnicity and depressive mood were related to worse perception of physical health. These findings support the relationship of a lack of resources to health status. A community-based programme of resources and health care services for the caregiver-care receiver dyad is recommended.

Human papillomavirus infections: epidemiology, pathogenesis, and therapy

BACKGROUND

Human papillomaviruses (HPV) are common human pathogens and are classified into more than 80 different types. These viruses produce benign warts in many cases and aggressive squamous cell carcinomas in other cases.

OBJECTIVE

The goal of this review is to update the reader on the epidemiology, pathogenesis, and therapy of HPV infections. Nonanogenital warts are transmitted by skin-to-skin contact while anogenital warts are usually transmitted sexually. Both types of warts produce much morbidity but rarely undergo malignant transformation. They are commonly treated with surgical or cytodestructive therapy, but immunomodulatory agents, such as imiquimod, have been proven to be very effective in anogenital warts and are being evaluated in nonanogenital warts. Other types of HPV have marked oncogenic potential such that over 99% of all cervical cancers and over 50% of other anogenital cancers are due to infection with oncogenic HPV. Many cofactors, such as cigarette smoking, genetics, and helper viruses, have potential roles in HPV oncogenesis, but their relative contributions are poorly understood. Other control measures for warts and HPV-associated cancers are under study, but the greatest future potential may be from the development of prophylactic and therapeutic vaccines.

CONCLUSIONS

Infection with HPV is very prevalent as are the clinical manifestations of this family of pathogens. Improved therapies for warts (e.g., imiquimod) have recently become available. Vaccines for HPV offer hope for future interventions for warts as well as for prevention of anogenital malignancies.

Loss of genomic methylation causes p53-dependent apoptosis and epigenetic deregulation

Cytosine methylation of mammalian DNA is essential for the proper epigenetic regulation of gene expression and maintenance of genomic integrity. To define the mechanism through which demethylated cells die, and to establish a paradigm for identifying genes regulated by DNA methylation, we have generated mice with a conditional allele for the maintenance DNA methyltransferase gene Dnmt1. Cre-mediated deletion of Dnmt1 causes demethylation of cultured fibroblasts and a uniform p53-dependent cell death. Mutational inactivation of Trp53 partially rescues the demethylated fibroblasts for up to five population doublings in culture. Oligonucleotide microarray analysis showed that up to 10% of genes are aberrantly expressed in demethylated fibroblasts. Our results demonstrate that loss of Dnmt1 causes cell-type-specific changes in gene expression that impinge on several pathways, including expression of imprinted genes, cell-cycle control, growth factor/receptor signal transduction and mobilization of retroelements.

Molecular characterization of a case of atransferrinemia

Hereditary atransferrinemia is a rare but instructive disorder that has previously been reported in only 8 patients in 6 families. It is characterized by microcytic anemia and by iron loading, and can be treated effectively by plasma infusions. We now report the first case known in the United States. We determined the sequences flanking the exons of the human transferrin gene and sequenced all of the exons and some of the flanking regions of the patient's DNA and that of her parents. The patient's DNA revealed a 10-base pair (bp) deletion, followed by a 9-bp insertion of a duplicated sequence. There was also a G-->C transversion at complementary DNA (cDNA) nt 1429, predicting that a proline was substituted for the alanine in amino acid position 477 (Ala 477 Pro). The latter mutation occurs at an evolutionarily highly conserved site; 704 control alleles were screened and this point mutation was not found. Each of the patient's transferrin genes contains one mutation, ie, the patient is a compound heterozygote for these mutations, because one was found in each of her parents. In addition to these mutations, which we regard to be causative in the patient's atransferrinemia, a silent polymorphism at cDNA 1572 G-->C was found in exon 13 as well as 2 previously unreported polymorphisms at IVS8 + 62 c-->t and IVS14-4 c-->a. The mutation in nt 1572 and that in intron 8 were common in the general population; the intron 14 mutation is rare.

Strange magnetism and the anapole structure of the proton

The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange quarks in generating nuclear magnetism. The measurement reported here provides an unambiguous constraint on strange quark contributions to the proton's magnetic moment through the electron-proton weak interaction. We also report evidence for the existence of a parity-violating electromagnetic effect known as the anapole moment of the proton. The proton's anapole moment is not yet well understood theoretically, but it could have important implications for precision weak interaction studies in atomic systems such as cesium.

Pharmacokinetic/pharmacodynamic modeling in drug research and development

The two domains in clinical pharmacology dealing with optimizing dosing recommendations are pharmacokinetics and pharmacodynamics. However, the usefulness of these disciplines is limited if viewed in isolation. Pharmacokinetic/pharmacodynamic (PK/PD) relationships and modeling builds the bridge between these two classical disciplines of clinical pharmacology. It links the concentration-time profile as assessed by pharmacokinetics to the intensity of observed response as quantified by pharmacodynamics. Thus, the resulting so-called integrated PK/PD-models allow the description of the complete time course of the desired and/or undesired effects in response to a drug therapy. PK/PD-modeling can elucidate the causative relationship between drug exposure and response and provide a better understanding of the sequence of events that result in the observed drug effect. This information can then be used to streamline the drug development process and dose optimization. This consensus paper presents an update on the current state of PK/PD-modeling from an academic, industrial and regulatory perspective.