Dispelling urban myths in healthcare risk management

Applied research to explore and challenge myths in healthcare risk management is pivotal to the growth of the profession. The authors demonstrate this process through exploring patient safety and malpractice issues on weekdays compared with on weekends and holidays. Analysis suggests that claim volume is driven by service volume.

alpha-MSH can control the essential cofactor 6-tetrahydrobiopterin in melanogenesis

In the human epidermis both keratinocytes and melanocytes express POMC m-RNA. Immunohistochemical studies of both cell types demonstrate significantly higher levels of alpha-MSH in melanocytes than in keratinocytes. Both cell types also hold the full capacity for de novo synthesis/recycling of the essential cofactor (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin (6BH4). 6BH4 is critical for the hydroxylation of the aromatic amino acids L-phenylalanine, L-tyrosine, and L-tryptophan, for nitric oxide production and in various immune modulatory processes. Recently it was shown that tyrosinase activity is regulated by 6BH4 through a specific allosteric inhibition. The tyrosinase/6BH4 inhibition can be activated by 1:1 complex formation between 6BH4 and alpha-MSH, but an excess of alpha-MSH over 6BH4 can inhibit tyrosinase due to complex formation by tyr2 in the alpha-MSH sequence. In both melanocytes and keratinocytes 6BH4 controls the L-tyrosine supply via phenylalanine hydroxylase (PAH). Recently we were able to show that the cellular uptake of L-phenylalanine and its intracellular turnover to L-tyrosine is crucial for melanogenesis. alpha-MSH can promote the production of L-tyrosine via PAH due to activation of the PAH tetramer to the more active dimer by removing 6BH4 from the regulatory binding domain on the enzyme. In conclusion, alpha-MSH can control (1) intracellular L-tyrosine formation from L-phenylalanine in both melanocytes and keratinocytes, and (2) tyrosinase activity, directly, in melanocytes.

In vivo and in vitro evidence for hydrogen peroxide (H2O2) accumulation in the epidermis of patients with vitiligo and its successful removal by a UVB-activated pseudocatalase

To date there is compelling in vitro and in vivo evidence for epidermal H2O2 accumulation in vitiligo. This paper reviews the literature and presents new data on oxidative stress in the epidermal compartment of this disorder. Elevated H2O2 levels can be demonstrated in vivo in patients compared with healthy controls by utilizing Fourier-Transform Raman spectroscopy. H2O2 accumulation is associated with low epidermal catalase levels. So far, four potential sources for epidermal H2O2 generation in vitiligo have been identified: (i) perturbed (6R)-L-erythro 5,6,7,8 tetrahydrobiopterin (6BH4) de novo synthesis/recycling/regulation; (ii) impaired catecholamine synthesis with increased monoamine oxidase A activities; (iii) low glutathione peroxidase activities; and (iv) "oxygen burst" via NADPH oxidase from a cellular infiltrate. H2O2 overproduction can cause inactivation of catalase as well as vacuolation in epidermal melanocytes and keratinocytes. Vacuolation was also observed in vitro in melanocytes established from lesional and nonlesional epidermis of patients (n = 10) but was reversible upon addition of catalase. H2O2 can directly oxidize 6BH4 to 6-biopterin, which is cytotoxic to melanocytes in vitro. Therefore, we substituted the impaired catalase with a "pseudocatalase". Pseudocatalase is a bis-manganese III-EDTA-(HCO3-)2 complex activated by UVB or natural sun. This complex has been used in a pilot study on 33 patients, showing remarkable repigmentation even in long lasting disease. Currently this approach is under worldwide clinical investigation in an open trial. In conclusion, there are several lines of evidence that the entire epidermis of patients with vitiligo is involved in the disease process and that correction of the epidermal redox status is mandatory for repigmentation.

A patient preference study comparing raltitrexed ('Tomudex') and bolus or infusional 5-fluorouracil regimens in advanced colorectal cancer: influence of side-effects and administration attributes

Current chemotherapy regimens used in advanced colorectal cancer (ACRC) are similar in terms of efficacy, but differ importantly in terms of side-effects and administration profiles. These differences may impact significantly on patients' lives. We have evaluated patient preferences between raltitrexed ('Tomudex') and 5-fluorouracil-based chemotherapy regimens, with regard to side-effect attributes (raltitrexed and Mayo regimens) and administration attributes (raltitrexed, Mayo, De Gramont and Lokich regimens) in a study based on 82 patients with ACRC. Patients completed a series of rating tasks on how 'upsetting' these attributes were to them using a visual analogue scale (VAS) in a structured interview conducted by a research nurse. Mucositis and asthenia were the most and least upsetting side-effects, respectively. The side-effect profile of raltitrexed was clearly preferred by 78% of patients versus 14% for Mayo (P < 0.001). When side-effects and administration attributes were combined into an overall profile, 91% of patients selected raltitrexed as their clearly preferred regimen, versus 6% for Mayo (P < 0.001). The administration regimen of raltitrexed was ranked most acceptable (mean rank score 1.5 compared with Mayo 2.6, De Gramont 2.7, and Lokich 3.3). Given similar palliative effects, patients with ACRC exhibit preferences for raltitrexed over other regimens, based on administration and/or side-effect attributes. Such preferences should constitute an important part of decisions relating to the choice of chemotherapy regimen in ACRC.

Anaesthesia clinical directors in the United Kingdom: organisation, objectives and support needs

A postal survey of all 269 acute hospital trusts identified in the United Kingdom was carried out to study the work of Clinical Directors of anaesthesia. Initial responses from 163 Clinical Directors and 129 completed questionnaires were analysed. Four main areas of concern revealed by the survey were contracts and objectives, funding of managerial sessions, access to information and perceived need for support. Most Clinical Directors had no job description and most had no formal written objectives, despite a substantial body of advice that these should be provided. There was generally substantial underfunding of managerial hours compared with those actually worked and approximately 20% of Clinical Directors surveyed had no funding for managerial duties. Clinical Directors' ratings of the information available to assist their decision making were also a cause of concern. Clinical Directors perceived that they need better networking, more training particularly on human resource management and improved management information.

Characterization of potential endocrine-related health effects at low-dose levels of exposure to PCBs

This article addresses issues related to the characterization of endocrine-related health effects resulting from low-level exposures to polychlorinated biphenyls (PCBs). It is not intended to be a comprehensive review of the literature but reflects workshop discussions. "The Characterizing the Effects of Endocrine Disruptors on Human Health at Environmental Exposure Levels," workshop provided a forum to discuss the methods and data needed to improve risk assessments of endocrine disruptors. This article contains an overview of endocrine-related (estrogen and thyroid system) interactions and other low-dose effects of PCBs. The data set on endocrine effects includes results obtained from mechanistic methods/ and models (receptor based, metabolism based, and transport protein based), as well as from (italic)in vivo(/italic) models, including studies with experimental animals and wildlife species. Other low-dose effects induced by PCBs, such as neurodevelopmental and reproductive effects and endocrine-sensitive tumors, have been evaluated with respect to a possible causative linkage with PCB-induced alterations in endocrine systems. In addition, studies of low-dose exposure and effects in human populations are presented and critically evaluated. A list of conclusions and recommendations is included.

Characterization of potential endocrine-related health effects at low-dose levels of exposure to PCBs

This article addresses issues related to the characterization of endocrine-related health effects resulting from low-level exposures to polychlorinated biphenyls (PCBs). It is not intended to be a comprehensive review of the literature but reflects workshop discussions. "The Characterizing the Effects of Endocrine Disruptors on Human Health at Environmental Exposure Levels," workshop provided a forum to discuss the methods and data needed to improve risk assessments of endocrine disruptors. This article contains an overview of endocrine-related (estrogen and thyroid system) interactions and other low-dose effects of PCBs. The data set on endocrine effects includes results obtained from mechanistic methods/ and models (receptor based, metabolism based, and transport protein based), as well as from (italic)in vivo(/italic) models, including studies with experimental animals and wildlife species. Other low-dose effects induced by PCBs, such as neurodevelopmental and reproductive effects and endocrine-sensitive tumors, have been evaluated with respect to a possible causative linkage with PCB-induced alterations in endocrine systems. In addition, studies of low-dose exposure and effects in human populations are presented and critically evaluated. A list of conclusions and recommendations is included.

Phase II study of weekly intravenous trastuzumab (Herceptin) in patients with HER2/neu-overexpressing metastatic breast cancer

The HER2/neu proto-oncogene is overexpressed in 25% to 30% of patients with breast cancer. Trastuzumab (Herceptin; Genentech, San Francisco, CA), a recombinant humanized monoclonal antibody with high affinity for the HER2 protein, inhibits the growth of breast cancer cells overexpressing HER2. In this phase II study the efficacy and toxicity of weekly administration of trastuzumab was evaluated in 46 patients with metastatic breast cancer whose tumors overexpressed HER2. A loading dose of 250 mg trastuzumab was administered intravenously, which was followed by 10 weekly doses of 100 mg each. Upon completion of this treatment period, patients with no disease progression could receive a weekly maintenance dose of 100 mg. Patients in this trial had extensive metastatic disease, and most had received prior anticancer therapy. Ninety percent of patients achieved adequate serum levels of trastuzumab. Toxicity was minimal, and no antibodies against trastuzumab could be detected. Objective responses were observed in 5 of the 43 evaluable patients, which included 1 complete remission and 4 partial remissions, for an overall response rate of 11.6%. Responses were seen in mediastinum, lymph nodes, liver, and chest wall lesions. Minor responses (seen in 2 patients) and stable disease (14 patients) lasted for a median of 5.1 months. These results demonstrate that trastuzumab is well tolerated and clinically active in patients with HER2-overexpressing metastatic breast cancers who have received extensive prior therapy. The regression of human cancer through the targeting of putative growth factor receptors such as HER2 warrants further evaluation of trastuzumab in the treatment of breast cancer.

Evaluation of a Treadmill with Vibration Isolation and Stabilization (TVIS) for use on the International Space Station

A treadmill with vibration isolation and stabilization designed for the International Space Station (ISS) was evaluated during Shuttle mission STS-81. Three crew members ran and walked on the device, which floats freely in zero gravity. For the majority of the more than 2 hours of locomotion studied, the treadmill showed peak to peak linear and angular displacements of less than 2.5 cm and 2.5 degrees, respectively. Vibration transmitted to the vehicle was within the microgravity allocation limits that are defined for the ISS. Refinements to the treadmill and harness system are discussed. This approach to treadmill design offers the possibility of generating 1G-like loads on the lower extremities while preserving the microgravity environment of the ISS for structural safety and vibration free experimental conditions.

Psychopathology in adopted and nonadopted children: a clinical sample

The relationships of adoptive status to presenting psychopathology and to demographic and psychosocial variables were examined in a large sample of children and adolescents who attended psychiatric outpatient services over a 14-year period. Adopted boys and girls were both at increased risk of disruptive behavior, including conduct disorders and ADHD. Age at time of adoption was not related to psychopathology.

Outpatient laparoscopic cholecystectomy: what predicts the need for admission?

Laparoscopic cholecystectomy (LC) is commonly performed as an outpatient (OP) procedure in selected patients, either in ambulatory surgery units associated with a hospital or in freestanding facilities. To identify factors that may preclude OPLC, a retrospective analysis of all patients who underwent LC by two surgeons from August 1996 through June 1998 was performed. A total of 126 patients were divided into three groups. Group I comprised 102 patients who underwent attempted elective OPLC. Group II comprised 20 patients who underwent LC on an emergent basis. Group III comprised 5 patients who were admitted before LC. Data were gathered regarding patient demographics, preoperative diagnoses, preoperative laboratory values, length of stay after surgery, and complications. These data were analyzed using logistic regression and univariate analysis. Age >60 and American Society of Anesthesiologists (ASA) class >2 appeared to be significant predictors of admission, but when considered together, neither was significant. The diagnosis of acute cholecystitis or biliary pancreatitis was highly predictive of admission in both groups. An ASA class >2 did predict postoperative stay of more than 12 hours. These data suggest that OPLC can be performed safely in unselected patients. However, those patients with an ASA class >2 or with a diagnosis of biliary pancreatitis or acute cholecystitis are more likely to require admission or postoperative stay over 12 hours, and these criteria should be considered relative contraindications to OPLC in free-standing facilities.

Multiple previous alcohol detoxifications are associated with decreased medial temporal and paralimbic function in the postwithdrawal period

BACKGROUND

Functional neuroimaging studies after alcohol cessation have demonstrated that chronic alcohol use globally reduces neuronal activity for several weeks. Less is known about the effects of previous alcohol use patterns on regional brain activity. Multiple previous alcohol detoxifications are associated with a worse clinical course and increased risk of seizures, perhaps due to sensitization of key brain structures. We performed the following imaging study in alcoholics in the postwithdrawal period to determine if blood flow in medial temporal structures would differ as a function of previous alcohol use (i.e., whether regions were kindled or sensitized due to multiple detoxifications).

METHODS

Fourteen adults meeting DSM-IV criteria for alcohol dependence (mean age 35, 8 SD; 10 men) and participating in a double-blind detoxification medication study underwent a brain perfusion Tc99 m-ECD (Neurolite) single photon emission computed tomography scan on days 7 through 9 (mean 7.6, .5 SD) after their last drink and 2 to 3 days since their last detoxification medication. Seven nonpsychiatrically ill, nonalcohol-dependent healthy adults were scanned as control subjects.

RESULTS

Alcoholics compared with controls had widely reduced relative activity in cortical secondary association areas and relatively increased activity in the medial temporal lobes (p < 0.01). Five alcoholic patients with > or = 2 previous detoxifications were compared with five patients in their first detoxification (age and detoxification medication matched). Multiple detoxification patients had significantly lower relative activity in bilateral anterior temporal poles and medial temporal lobes and in visual cortex (p < 0.01) compared with first episode patients.

CONCLUSIONS

These studies are consistent with other studies comparing alcoholics and controls. They also suggest that on day 7 of detoxification, alcoholic subjects with multiple previous detoxifications have decreased visual cortex, medial temporal lobes, and anterior paralimbic blood flow, compared with those in their first detoxification. Further studies seem warranted to confirm these initial exploratory results.

Gene therapy with autologous, interleukin 2-secreting tumor cells in patients with malignant melanoma

We vaccinated metastatic melanoma patients with irradiated, autologous melanoma cells genetically engineered to secrete interleukin 2 (IL-2) to investigate whether an anti-tumor immune response would be induced. Melanoma cell cultures were established from surgical specimens and were engineered to secrete IL-2 by infection with recombinant retrovirus. Twelve patients were vaccinated subcutaneously one, two, or three times with approximately 10(7) irradiated, autologous, IL-2-secreting tumor cells. Treatment was well tolerated, with local reactions at 11 of 24 injection sites and minor systemic symptoms of fever and headache after 6 injections. One patient developed anti-tumor DTH after the first vaccination and showed an increased response after the second vaccination. Anti-autologous tumor CTLs could be detected prevaccination in the peripheral blood of seven patients and their activity increased after vaccination in four patients. No UICC-defined clinical responses were seen, but three patients had stable disease for 7-15 months, one of whom has not yet progressed (15+ months). Thus, patient vaccination with autologous, genetically engineered tumor cells is feasible and safe. Anti-tumor DTH and CTLs can be induced in some patients with such a vaccine.

Sequence-divergent units of the ABA-1 polyprotein array of the nematode Ascaris suum have similar fatty-acid- and retinol-binding properties but different binding-site environments

Polyproteins comprise long polypeptides that are post-translationally cleaved into proteins of different function, or tandemly repetitive polypeptides which are processed into multiple versions of proteins which are presumed to have the same function. In the latter case the individual units of the polyprotein can differ substantially in sequence. Identity of function between the different units therefore cannot be assumed. Here we have examined the ABA-1 polyprotein allergen of the parasitic nematode Ascaris suum and found it to contain units which show a 50% difference in amino acid sequence. The parasite therefore produces at least two radically different forms of the allergen encoded within the polyprotein array. In fluorescence-based ligand-binding assays, recombinant polypeptides representing the two forms (designated ABA-1A1 and ABA-1B1) showed similar binding affinities for a range of fluorescent active-site probes [retinol, dansylundecanoic acid, dansyl-DL-alpha-amino-octanoic acid, cis-parinaric acid (cPnA)] and for the non-specific hydrophobic surface probe 8-anilinonaphthalene-1-sulphonic acid. However, the molecular environments in the active sites are markedly different, as indicated by disparate fluorescence emission peaks and intensities of bound probes. CD showed that the proteins have similar secondary structures but differ in susceptibility to chemical denaturation/unfolding by guanidinium chloride. Both retain a single conserved tryptophan residue in a characteristic non-polar environment, as revealed by extreme fluorescence blue shift. Thus the gross differences in sequence of the two proteins are not reflected in their ligand-binding specificities but in their binding-site environments.

Sexual practices in a cohort of US women with and without human immunodeficiency virus. HERS Study. HIV Epidemiology Research Study

OBJECTIVES

To compare the frequency and pattern of sexual activities of women infected with human immunodeficiency virus (HIV) relative to uninfected women at the time of enrollment into a multisite cohort study.

METHODS

The HIV Epidemiology Research Study (HERS) is a prospective study following 873 HIV-infected and 438 HIV-uninfected women. The baseline protocol included interviews about sexual practices, sociodemographic information, and drug and alcohol use, as well as clinical and laboratory studies. Multiple logistic regression models estimated differences between infected and uninfected women in relation to sexual activity and practice.

RESULTS

77% of infected women and 89% of uninfected women reported at least one sexual partner in the six months before study entry. Among sexually active women, specific practices varied little by HIV serostatus, with the exception of oral sex, which was more frequently performed and received by uninfected women. Despite the high prevalence of sexual activity, infected women were 2.5 times as likely not to have had any recent sexual partners as uninfected women (95% CI = 1.77-3.44).

CONCLUSIONS

Women who decrease or altogether stop engaging in sexual partnerships may benefit from direct counseling in relation to underlying loss of sexual affection.