Immediate hypersensitivity to chlorhexidine is increasingly recognised in the United Kingdom.

BACKGROUND: Chlorhexidine is widely used as an antiseptic agent. It is a potentially allergenic substance that can cause severe hypersensitivity reactions. OBJECTIVE: We describe six patients who had anaphylactic reactions attributed to chlorhexidine during surgery. These patients were exposed to chlorhexidine in gels, swabs and catheters. MATERIALS AND METHODS: Six patients from three UK centres with clinical history suggestive of anaphylaxis during surgery are reported. Detailed history, review of case notes, determination of chlorhexidine specific IgE, mast cell tryptase and skin tests were performed. RESULTS: On detailed assessment five of six patients demonstrated a previous history of reactions on re-exposure to chlorhexidine. All six patients had elevated specific IgE to chlorhexidine. Skin prick test with chlorhexidine was performed in four of the six patients and was found to be positive. CONCLUSION: Immediate hypersensitivity to chlorhexidine appears to be common but underreported in the UK. We recommend that centres investigating patients with reactions during anaesthesia and surgery should routinely include testing for chlorhexidine allergy.

Serotonin-norepinephrine reuptake inhibitor therapy in late-life depression is associated with increased marker of bone resorption.

UNLABELLED: Antidepressants are associated with bone loss and fractures in older adults. We treated depressed older adults with an antidepressant and examined its effects on bone turnover by comparing blood samples before and after treatment. Bone resorption increased after antidepressant treatment, which may increase fracture risk. INTRODUCTION: Antidepressants have been associated with increased bone loss and fractures in older adults in observational studies, but the mechanism is unclear. We examined the effects of a serotonin-norepinephrine reuptake inhibitor, venlafaxine, on biomarkers of bone turnover in a prospective treatment study of late-life depression. METHODS: Seventy-six individuals aged 60 years and older with current major depressive disorder received a 12-week course of venlafaxine XR 150-300 mg daily. We measured serum C-terminal cross-linking telopeptide of type I collagen (ß-CTX) and N-terminal propeptide of type I procollagen (P1NP), measures of bone resorption and formation, respectively, before and after treatment. We then analyzed the change in ß-CTX and P1NP within each participant. Venlafaxine levels were measured at the end of the study. We assessed depression severity at baseline and remission status after treatment. RESULTS: After 12 weeks of venlafaxine, ß-CTX increased significantly, whereas P1NP did not significantly change. The increase in ß-CTX was significant only in participants whose depression did not remit (increase by 10 % in non-remitters vs. 4 % in remitters). Change in ß-CTX was not correlated with serum levels of venlafaxine or norvenlafaxine. CONCLUSION: Our findings suggest that the primary effect of serotonergic antidepressants is to increase bone resorption. However, such an increase in bone resorption seemed to depend on whether or not participants' depression remitted. Our results are in agreement with prior observational studies reporting increased bone loss in older adults taking serotonergic antidepressants. These negative effects on bone homeostasis could potentially contribute to increased fracture risk in older adults.

Broadband infrared study of pressure-tunable Fano resonance and metallization transition in 2H-[Formula: see text].

High pressure is a proven effective tool for modulating inter-layer interactions in semiconducting transition metal dichalcogenides, which leads to significant band structure changes. Here, we present an extended infrared study of the pressure-induced semiconductor-to-metal transition in 2H-[Formula: see text], which reveals that the metallization process at 13-15 GPa is not associated with the indirect band-gap closure, occurring at 24 GPa. A coherent picture is drawn where n-type doping levels just below the conduction band minimum play a crucial role in the early metallization transition. Doping levels are also responsible for the asymmetric Fano line-shape of the [Formula: see text] infrared-active mode, which has been here detected and analyzed for the first time in a transition metal dichalcogenide compound. The pressure evolution of the phonon profile under pressure shows a symmetrization in the 13-15 GPa pressure range, which occurs simultaneously with the metallization and confirms the scenario proposed for the high pressure behaviour of 2H-[Formula: see text].

Do ribosomopathies explain some cases of common variable immunodeficiency?

The considerable clinical heterogeneity of patients with common variable immunodeficiency disorders (CVID) shares some similarity with bone-marrow failure disorders such as Diamond-Blackfan anaemia (DBA) and Shwachman-Diamond syndrome (SDS), now recognized as defects in ribosome biogenesis or ribosomopathies. The recognition of a patient with DBA who subsequently developed CVID lends support to our previous finding of a heterozygous mutation in the SBDS gene of SBDS in another CVID patient, suggesting that ribosome biogenesis defects are responsible for a subset of CVID. Genetic defects in the ribosomal translational machinery responsible for various bone marrow failure syndromes are recognized readily when they manifest in children, but diagnosing these in adults presenting with complex phenotypes and hypogammaglobulinaemia can be a challenge. In this perspective paper, we discuss our clinical experience in CVID patients with ribosomopathies, and review the immunological abnormalities in other conditions associated with ribosomal dysfunction. With genetic testing available for various bone marrow failure syndromes, our hypothesis that ribosomal abnormalities may be present in patients with CVID could be proved in future studies by testing for mutations in specific ribosomal genes. New knowledge might then be translated into novel therapeutic strategies for patients in this group of immunodeficiency disorders.

Abnormal O-glycosylation of CD43 may account for some features of Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS) is an X-linked immunodeficiency disorder characterized by eczema, recurrent infections, thrombocytopenia and small platelets. There is an increased incidence of autoimmune phenomena particularly autoimmune haemolytic anaemias and vasculitic disorders. Mutations in the WASP gene encoding the cytoskeleton regulatory protein WASp (Wiskott-Aldrich syndrome protein) result in abnormal protein activity with defective cytoplasmic signaling and actin polymerization. This accounts for abnormal T cell responses to proliferation and susceptibility to infections, but does not fully explain the autoimmune phenomena nor the progressive lymphopenia seen in these patients. Wiskott Aldrich patients also demonstrate abnormal O-glycosylation of a highly conserved transmembrane glycoprotein CD43 that is expressed on most haemopoeitic cells. The altered glycosylation pattern on WAS lymphocytes is due to increased beta1-->6 GlcNACtransferase activity which leads to branched core 2 glycans or lower molecular forms of CD43 glycoprotein. The clinical hypothesis put forward is that abnormal O-glycosylation of CD43 may underlie the development of the autoimmune disorders and the progressive lymphopenia observed in WAS patients. Regulation of glycosylation of CD43 is important in the selection process of T cells within the thymus and abnormalities of glycosylation may cause many immune perturbations, such as the escape of self-reactive T cells into the periphery and subsequent development of autoimmune disease in these patients.

Coexistence of pressure-induced structural phases in bulk black phosphorus: a combined x-ray diffraction and Raman study up to 18 GPa.

We report a study of the structural phase transitions induced by pressure in bulk black phosphorus by using both synchrotron x-ray diffraction for pressures up to 12.2 GPa and Raman spectroscopy up to 18.2 GPa. Very recently black phosphorus attracted large attention because of the unique properties of few-layers samples (phosphorene), but some basic questions are still open in the case of the bulk system. As concerning the presence of a Raman spectrum above 10 GPa, which should not be observed in an elemental simple cubic system, we propose a new explanation by attributing a key role to the non-hydrostatic conditions occurring in Raman experiments. Finally, a combined analysis of Raman and XRD data allowed us to obtain quantitative information on presence and extent of coexistences between different structural phases from ~5 up to ~15 GPa. This information can have an important role in theoretical studies on pressure-induced structural and electronic phase transitions in black phosphorus.

Best practice in primary care pathology: review 6.

This sixth best practice review examines four series of common primary care questions in laboratory medicine: (1) laboratory monitoring in hypertension and heart failure abnormalities; (2) markers of inflammatory joint disease; (3) laboratory investigation of chronic diarrhoea; and (4) mumps and chickenpox. The review is presented in question-answer format, referenced for each question series. The recommendations represent a precis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by Medline Embase searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus based rather than evidence based. They will be updated periodically to take account of new information.

Temperature dependent EXAFS study on transition metal dichalcogenides MoX2 (X = S, Se, Te).

The local structure of molybdenum dichalcogenide MoX2 (X = S, Se, Te) single crystal has been studied by means of multi-edge (Mo, Se, and Te K-edges) extended x-ray absorption fine-structure spectroscopy as function of temperature. The temperature dependences of the interatomic distances Mo-X, Mo-Mo and X-X (X = S, Se, and Te) and of the corresponding Debye-Waller factors have been extracted over the 70-500 K temperature range. Exploiting the correlated Einstein model, we found that the Einstein frequencies of Mo-X and X-X bonds obtained by present data are in close agreement with the frequencies of the optical (Raman and infrared) stretching modes for both MoS2 and MoSe2, whereas a significant deviation has been found for MoTe2. A similar anomaly has been found for the force constants related to the Mo-X bonds in the MoTe2 case. Our findings, accordingly with the results reported in a recent theoretical paper, support the idea that the optical vibrational modes have a dominant role in MoS2 and MoSe2, whereas the effects of acoustic vibrational modes cannot be neglected in the case of MoTe2.

A comparative EPR, infrared and Raman study of natural and deproteinated tooth enamel and dentin.

The aim of the present work was to investigate how the native signal observed in the electron paramagnetic resonance (EPR) spectrum of tooth enamel and dentin is associated with the organic content of the two tissues. This was achieved by comparing the EPR native signal and the optical bands (Raman and infrared, IR) associated with organic components of tooth enamel and dentin, in natural and deproteinated samples. The main results were: (a) in natural samples, the organic optical bands are more intense in dentin than in enamel, in contrast with the EPR native signal which shows similar intensity in the two tissues; (b) after deproteination, the optical organic bands are completely suppressed in both dentin and enamel, while the EPR native signal is eliminated only in dentin. It is suggested that the IR and Raman organic bands are originated in the bulk of the organic matrix, while the paramagnetic centres associated with the EPR native signal are located in the organic-mineral interface.

Investigation of IgG4 levels in atopic patients using a competitive inhibition assay employing biotinylated IgG4 myeloma and avidin peroxidase.

Modification of a 'sandwich' ELISA assay developed for the determination of serum IgE levels proved to be unsatisfactory for the measurement of IgG4. This was attributed to the limited capacity of the microtitre plate solid phase which required high serum dilutions in order to measure IgG4 levels. To overcome this problem a competitive inhibition assay was developed with monoclonal anti-IgG4 attached to the plate. In this system biotinylated IgG4 myeloma and sample IgG4 compete for the limited antibody binding sites present on the solid phase. The attached biotinylated myeloma is detected by addition of avidin conjugated with peroxidase and following development with substrate, IgG4 levels are calculated by reference to a calibrated inhibition curve. The inhibition ELISA assay has been used clinically to measure IgG4 levels in atopic and normal individuals and the values obtained correlated closely (r = 0.99) with the IgG4 levels determined by radial immunodiffusion. For 43 atopic dermatitis patients investigated the median IgG4 level was 1.1 g/l which was significantly elevated when compared to a median of 0.385 g/l for 60 blood donors (P less than 0.0001, Mann-Whitney U). Among the 47 hay fever patients investigated the median was 0.6 g/l which, although lower than in atopic dermatitis, was again significantly increased (P less than 0.025). Within this latter group, 25 patients were investigated for the effects of desensitization with commercial grass pollen injections. The total IgG4 showed a variable but significant rise between the start and finish of treatment (P less than 0.01 Wilcoxon signed ranks test).

Changes in acquired immunodeficiency syndrome-related risk behavior after adolescence: relationships to knowledge and experience concerning human immunodeficiency virus infection.

This paper explores the extent of change in acquired immunodeficiency syndrome (AIDS) risk level and in the numbers of AIDS-related risk behaviors in 602 inner-city adolescents as they enter young adulthood. Youths' risk level for human immunodeficiency virus (HIV) infection during adolescence was categorized as high (engaging in prostitution, male homosexual or bisexual activity, or injectable drug use or having ulcerative sexually transmitted diseases), moderate (having six or more sex partners in a 1-year period or nonulcerative sexually transmitted diseases), or low (none of the above). Although a proportion at high or moderate risk during adolescence did move to lower risk levels by young adulthood, the overall risk level stayed fairly stable: 45% were at high or moderate risk levels during adolescence, and 35% were at those levels by young adulthood. Then change in the total number of risk behaviors engaged in by the youths was examined. Knowledge about AIDS or HIV infection and its prevention was not associated with any change in risk behavior, nor were the number of sources of information about the epidemic, acquaintance with those who are infected, estimates of personal risk, or exposure to HIV-test counseling. In fact, youths whose risk behaviors increased the most were more likely to know someone who had died of AIDS and to estimate their own risk as high. Most youths reported that they did not use condoms regularly, disliked them, and had little confidence in their protective ability. Changes in preventive strategies and further research on the causes of behavior change are needed.

Long-term evolution of daytime somnolence in patients with sleep apnea/hypopnea syndrome treated by continuous positive airway pressure.

We demonstrated in a previous study that excessive daytime sleepiness (EDS) in patients who have sleep apnea/hypopnea syndrome (SAHS) and are undergoing continuous positive airway pressure (CPAP) treatment improved differently in two groups of patients: in group I, multiple sleep latency tests (MSLT) were normalized after 50 days of treatment (individual value > 10 minutes), whereas they remained low (individual value < 10 minutes) in group II, with a significant difference between groups. To evaluate the long-term evolution of daytime somnolence under nasal CPAP treatment, five patients from group I and seven patients from group II underwent a new polysomnography and MSLT 4 years after the previous study. Clinical, polysomnographic and MSLT results obtained at baseline before treatment (T1), after the initial 50-day period of CPAP treatment (T2), and after 4 years (T3) were compared. The significant difference in mean MSLT value between the two groups previously observed at T1 and T2 disappeared at T3 (group I: 12.4+/-5.9 minutes; group II: 9.7+/-5.9 minutes). We found that this long-term improvement in excessive daytime somnolence was independent of the initial MSLT value, the severity of SAHS, and the initial MSLT changes under nasal CPAP. Long-term MSLT evolution was significantly correlated to CPAP compliance. These results demonstrate that even in the absence of a significant increase in MSLT at the beginning of CPAP treatment, further improvement is still possible several years later, which may encourage the regular, long-term use of nasal CPAP by patients.

Atrial arrhythmia as a complication of nasal CPAP.

We report a case of supraventricular rhythm disorder occurring as a complication of nasal continuous positive airway pressure (CPAP) in sleep apnea syndrome treatment. The investigations showed a preexisting atrial vulnerability revealed by positive pressure ventilation, hemodynamic changes with decreased cardiac output, and a rise in the right atrial pressure. Such complications may develop further studies to evaluate cardiovascular repercussions of nasal CPAP.

Predictive factors of long-term compliance with nasal continuous positive airway pressure treatment in sleep apnea syndrome.

The long-term acceptability of treatment with nasal continuous positive airway pressure (CPAP) was studied prospectively in 44 patients with obstructive sleep apnea syndrome. At 14 months on the average after starting treatment with CPAP, 30 patients (68 percent) were found to be compliant (characterized by use of the apparatus every night throughout the night, for more than 5 h per night). The daily use of nasal CPAP was significantly correlated to the initial apnea/hypopnea index (p = 0.013; r = 0.37), as well as to the percentage of light sleep (p = 0.045; r = 0.30) and slow-wave sleep (p = 0.037; r = -0.31) during the initial polygraphic recording. We found a strong correlation between the daily use of nasal CPAP and the difference in the apnea/hypopnea index (p = 0.025; r = -0.34), the difference in mean oxygen saturation during sleep (p = 0.013; r = 0.38), and the difference in hypersomnia scores (p = 0.006; r = -0.40) obtained before and after treatment by nasal CPAP. Thus, patients used CPAP much more if they had an initial significant clinical handicap and if they were aware of the beneficial effects of CPAP. Under these conditions, patients tended to use the apparatus for the optimal length of time, regardless of the side effects linked to the treatment. This ensured efficacy and the maintenance of good compliance. This study confirms the importance of supervision of the time counter, as well as regular encouragement of patients to use the treatment as long as possible each night, in order to extract a maximum benefit from treatment by nasal CPAP.

Changes in T cell subsets, interleukin-6 and C-reactive protein after laparoscopic and open colorectal resection for malignancy.

BACKGROUND: Attenuation of the immune response to surgery, as demonstrated with the laparoscopic approach to cholecystectomy, has potential benefits in patients undergoing laparoscopic colonic resection for malignancy. We aimed to study the perioperative immune response in patients undergoing laparoscopically assisted and open surgery for colorectal cancer. METHODS: This study involved 23 patients undergoing laparoscopically assisted (n = 13) and open surgery (n = 10). Interleukin-6 (IL-6) C-reactive protein (CRP), the total lymphocyte count, and the CD3, CD4, CD8, CD16, and CD19 lymphocyte subpopulations were assayed preoperatively and at 4, 8, 10, 24, 48, and 168 h postoperatively. RESULTS: Significant rises in IL-6 and CRP were demonstrated within 4 and 24 h, respectively (p < 0.001) in both groups. However, no significant difference between the groups was seen. Significant decreases in total lymphocyte count and all T cell subsets were demonstrated in both groups, beginning at 4 h (p < 0.01). However, no significant difference between the groups was seen. All parameters, excluding CRP, had returned to baseline by 7 days postoperatively in both groups. CONCLUSIONS: Patients with malignancy exhibit significant perioperative immune disturbance with laparoscopically assisted and open surgery. The current data do not provide justification for the laparoscopically assisted approach on grounds of immune preservation.

Nosocomial pneumonia with isolation of anaerobic bacteria in ICU patients: therapeutic considerations and outcome.

PURPOSE: Evaluate the influence of the anti-anaerobic antimicrobial therapy in the outcome of patients with nosocomial pneumonia. MATERIALS AND METHODS: The population study included 53 intensive care unit patients with nosocomial pneumonia in whom, using a protected specimen brush, anaerobic bacteria were isolated, which were associated or not with aerobes. Current and empirical antibiotherapies were retrospectively analyzed, regarding their efficacy against anaerobic bacteria. Since it was debated, sensitivity to cefotaxime, ceftazidime, and ciprofloxacin was determined in 38 strains of Prevotella species. Outcome was evaluated 10 days after the day of protected specimen brushes. Improvement was defined as a decrease of Murray score or ventilator weaning. RESULTS: The most frequently isolated bacteria were Prevotella species, which were more frequently resistant to cefotaxime (37%), ceftazidime (50%), and ciprofloxacine (32%) than usually reported in the literature. Sixty-six percent of these strains produced beta-lactamase. The effect of empirical anti-anaerobic antibiotherapy on the outcome at day 10 was evaluable in 39 patients. Twenty-nine patients were improved and 10 patients worsened. Interestingly, patients who had received well-adapted antibiotics against anaerobes had a better outcome after 10 days (P < .02). CONCLUSIONS: This study suggests that specific antianaerobic therapy may be considered in the choice of empirical antibiotherapy in patients with nosocomial pneumonia.

Post-hospital home care for African-American and white elderly.

This study of 208 chronically ill African-American and white elderly entering home care after hospitalization examined race differences in informal and formal services received and adequacy of care. Controlling for marital status, interference in activities from chronic conditions, socioeconomic status, age, and gender in regression analyses, African-Americans received significantly fewer hours of formal care per week but received significantly more hours of informal care per week from the primary caregiver. However, there was a tendency for African-Americans to rate their care as less adequate. Implications of the findings for practice, policy, and research are discussed.

Adolescents' and providers' perspectives on the need for and use of mental health services.

PURPOSE: This study examines need for and use of services from both the adolescent's and the service provider's viewpoints. METHODS: The Youth Services Project interviewed 792 youths from the juvenile justice, education, primary health care, and child welfare sectors (200 each); gathered anonymous tallies of the mental health of youthful clients at each sector; and conducted focus groups with providers. RESULTS: A high percentage of youths (12-15%) met DSM-IV criteria for a mental health disorder, yet the sector clients were not identified as having mental health problems. Juvenile justice and child welfare sectors identified the highest percentage of adolescent clients as having mental health problems, and provided the most services (50-80%). The primary health care sector recorded no mental health disorders among the tallied clients, and provided the fewest mental health services (< 20%). Providers' complaints that they lacked knowledge concerning mental health assessment and lacked referral or treatment resources closely paralleled the degree to which their sector underserviced youths. CONCLUSION: Lack of knowledge about the extent of need in adolescents, methods for assessing or treating, and referral resources handicap service providers and explain the gap between need and service.

The association of physical and sexual abuse with HIV risk behaviors in adolescence and young adulthood: implications for public health.

This paper explores the relationship between changes in HIV risk behaviors and physical and sexual abuse. A stratified random sampling procedure selected 602 youths from a sample of 2,787 patients seen consecutively at public health clinics in 10 cities. Face-to-face structured interviews conducted since 1984-85 provide a history of change in risk behavior from adolescence to young adulthood. Univariate and bivariate analyses assessed differences in demographic and number and type of risk behaviors between those experiencing single or multiple types of abuse and those with no abuse history at all. The results show that a history of physical abuse, sexual abuse, or rape is related to engaging in a variety of HIV risk behaviors and to a continuation or increase in the total number of these behaviors between adolescence and young adulthood. This information might help practitioners to both prevent initial involvement in HIV risk behaviors and to prevent continuation of behaviors as youths move into young adulthood.