Drug target validation: lethal infection blocked by inducible peptide

Genome projects are generating large numbers of potential new targets for drug discovery. One challenge is target validation, proving the usefulness of a specific target in an animal model. In this paper, we demonstrate a new approach to validation and assay development. We selected in vitro specific peptide binders to a potential pathogen target. By inducing the expression of a selected peptide in pathogen cells causing a lethal infection in mice, the animals were rescued. Thus, by combining in vitro selection methods for peptide binders with inducible expression in animals, the target's validity was rigorously tested and demonstrated. This approach to validation can be generalized and has the potential to become a valuable tool in the drug discovery process.

Lung delivery of aerosolized dextran

The ability of nebulizers to deliver dextran (nominal molecular mass, 4,000 g/mol) to the lung as an inhaled aerosol is evaluated by in vitro experimental methods and mathematical models. Dextran in isotonic saline was aerosolized by four nebulizer types (Pari LC STAR, Hudson T-Updraft II, Acorn II, and Sonix 2000) at dextran concentrations </= 400 mg/ml and with 2.5- and 4-ml volume fills. Aerosols inhaled during breath simulation were characterized by in-line phase Doppler anemometry, filter collection, osmometry, and gravimetry. Mathematical models were used to estimate amounts of the characterized aerosols depositing in the different regions of lung models, and mathematical models of mucous thickness were then developed to estimate initial concentrations of the depositing dextran in the mucus of each conducting airway generation. Models of three subjects (4 yr old, 8 yr old, and adult) were used. The high viscosity of the dextran solutions tested (up to seven times that of water) negatively impacts nebulization, and results in poor performance with most delivery systems tested. Our results suggest that airway mucosal dextran concentrations associated with efficacy in previous animal and in vitro models are achievable with reasonable delivery times (</= 12 min) with only one of the delivery systems/formulations tested: the Pari LC STAR nebulizer, using a 2. 5-ml volume fill and a dextran concentration of 200 mg/ml.

Treatment of heterotopic cervical and intrauterine pregnancy

OBJECTIVE

To find a suitable technique to selectively terminate a cervically implanted embryo while maintaining viability of a concomitant intrauterine pregnancy.

METHODS

A 34-year-old patient achieved a twin pregnancy after 4 IVF attempts. Ultrasound revealed a viable intrauterine and cervical pregnancy. Given our experience with KCl injection for fetal reduction, we offered the patient an attempt to reduce the cervical pregnancy.

RESULTS

Best visualization in this case was obtained by transabdominal scanning. A 6-inch 20-gauge spinal needle was inserted transcervically and maneuvered into the thorax of the embryo. Fetal heart rate ceased even before KCl could be injected. Then 3 cm(3) of saline were injected to provide better visualization of the cervical fetus, and to confirm absence of heart beat. The patient had minor vaginal bleeding for several days. The intrauterine pregnancy progressed uneventfully through 36(1)/(2) weeks with delivery of a healthy, 2, 700-gram newborn.

CONCLUSION

Cervical pregnancy is usually considered a life-threatening event. Other factors such as concomitant intrauterine pregnancy and the patient's infertility history generally would be secondary concerns. In this case, we were able to selectively terminate the cervical pregnancy, while preserving the intrauterine one, allowing this couple to have a healthy newborn. Further cases will be necessary to appropriately define risk rates for such an approach.

The teaching and learning principles of metropolitan Aborigines with diabetes

This study was undertaken at a leading Aboriginal health agency in Adelaide called Nunkuwarrin Yunti (King & Wilson 1998). One of the aims not previously reported involved identifying the way that metropolitan Aborigines prefer to learn about their diabetes management. An ethnographic approach was used to interview ten Aboriginal health professionals and four clients (n = 14) about this topic. The results indicated the worldview held by metropolitan Aborigines about diabetes health care, the Aboriginal learner, beliefs about teaching and learning, the characteristics of an effective teacher and a suggested teaching plan.

Mucus-controlling agents: past and present

Airway mucus is the secretory product of the mucous cells. The mucus is a variable mixture of water, mucous glycoproteins, low molecular weight ions, proteins, and lipids, the physical properties of which are important for airway defense. The factors that contribute to the physical properties of mucus are complex, and there are several pharmacologic strategies that potentially can serve to improve the clearability of airway mucus. In vitro results suggest potential benefit from the additive effects of selected combinations of mucoactive medications. Further studies are required to confirm these findings, to perform direct assessments of mucus clearability, and to extend the observations to patients with various types of pulmonary diseases for which mucoactive treatments are required.

Non-attendance at psychiatric outpatient clinics: communication and implications for primary care

BACKGROUND

What should happen when an outpatient fails to attend a psychiatric clinic? Guidelines from the General Medical Services Committee suggest that general practitioners (GPs) have no further responsibility of care for a patient once a referral to a psychiatrist has been made. This raises questions about the formulation of effective management plans for those patients with whom psychiatric services find it difficult to engage due to non-compliance with assessment and follow-up.

AIMS

To investigate communication between GPs, patients, and psychiatrists at referral and following attendance or non-attendance at outpatient appointments.

METHOD

A prospective study of a random sample of attenders and non-attenders at psychiatric outpatient clinics. Patients and GPs were interviewed to obtain data about the referral process. GPs' views on communication from psychiatrists and the appropriate course of action following clinic non-attendance were investigated. The quality of referral and clinic letters for attenders and non-attenders was compared.

RESULTS

There was no difference in the quality of referral letter for attenders and non-attenders. Psychiatrists were less likely to write to GPs about follow-up patients' appointments than new patients' appointments; communication was least likely when a follow-up patient missed their appointment. GPs considered follow-up non-attenders were more likely to need a further appointment than new patient non-attenders, but did not identify a role for themselves in engaging with follow-up non-attenders.

CONCLUSION

Communication between GPs and psychiatrists about new patients seems adequate. However, there are important deficits in communication from psychiatrists to GPs about follow-up patients, especially non-attenders who are often more severely ill and difficult to engage. An effective response for this group is likely to need cooperative health and social service action rather than rigid guidelines concerning clinical responsibility.

Conducting randomized trials in general practice: methodological and practical issues

The evaluation of the outcome of health services technologies is a requirement for their efficient provision in clinical practice. The most reliable evidence for treatment efficacy comes from randomized trials. Randomized trials in general practice pose particular methodological and practical difficulties. In this paper, we discuss how best to plan and manage a clinical trial in this setting. We base our discussion on our experience of conducting randomized trials to evaluate the effectiveness of brief psychotherapy in general practice.

Antagonism of heroin and morphine self-administration in rats by the morphine-6beta-glucuronide antagonist 3-O-methylnaltrexone

In mice, 3-O-methylnaltrexone blocks the analgesic actions of morphine-6beta-glucuronide and heroin at doses which are inactive against morphine. We found a similar selectivity in rats. 3-O-Methylnaltrexone antagonized the analgesic actions of 6-acetylmorphine in Sprague-Dawley rats and heroin in Wistar rats at doses that were inactive against morphine. Inclusion of a fixed dose of 3-O-methylnaltrexone significantly shifted the analgesic dose-response curves for 6-acetylmorphine and heroin without altering the morphine dose-response curves. In a self-administration model, 3-O-methylnaltrexone treatment significantly increased both heroin and morphine intake during the first hour, suggestive of an antagonist effect. This effect at doses of 3-O-methylnaltrexone which were inactive against morphine analgesia implied a role for the morphine-6beta-glucuronide opioid receptor in the reinforcing properties of heroin and morphine.

Acute effects of inhalable particles on the frog palate mucociliary epithelium

This work was designed to evaluate the toxicity of inhalable particles [less than/equal to] 10 microm in aerodynamic diameter (PM(10)) collected from the urban air in São Paulo, Brazil, to the mucociliary apparatus using the frog palate preparation. Seven groups of frog palates were immersed in different concentrations of PM(10) diluted in Ringer's solution during 120 min: 0 (control, n = 31); 50 (n = 10); 100 (n = 9); 500 (n = 28); 1,000 (n = 10); 5,000 (n = 11); and 10,000 microg/m(3) (n = 10). Mucociliary transport and transepithelial potential difference were determined at 0, 30, 60, and 120 min exposure. Additional groups (control and 500 microg/m(3)) were studied by means of morphometric analyses (quantification of the amount of intraepithelial and surface mucins), measurement of cilia beat frequency, and quantification of total glutathione. Mucociliary transport and transepithelial potential difference were significantly decreased at higher concentrations of PM(10) (p = 0.03 and p = 0.02, respectively). Exposure to PM(10) also elicited a significant decrease of total glutathione (p = 0. 003) and depletion of neutral intraepithelial mucins (p = 0.0461). These results show that PM(10) can promote significant alterations in ciliated epithelium in vitro.

Symptoms 2 weeks, 3 months and 12 months after treatment of early breast cancer: the patients’ perspectives

The physical symptoms and side-effects reported by patients treated for early breast cancer with surgery (S), (breast conservation or mastectomy), radiotherapy (R) and chemotherapy (C) are reported. As part of a large quality-of-life study, eligible patients were invited to complete a questionnaire at three and 12 months after treatment for early breast cancer. Symptoms 2 weeks after surgery were retrospectively collected at the 3-month questionnaire. Comparing the commonly used different therapy combinations (S, S+R, S+C and S+R+C) we found the only loco-regional symptom to show a significant difference between these groups was chest tightness (P<0.001). Both anxiety about attending for and discomfort during C were significantly higher than during R (P<0.00005 and 0.00001 respectively). We found that the addition of R and, or, C to S resulted in surprisingly little variation in physical side-effects.

Dermal and transdermal delivery of protein pharmaceuticals: lipid-based delivery systems for interferon alpha

The dermal and transdermal delivery of protein pharmaceuticals faces enormous challenges, and at the same time has very significant potential for the non-invasive treatment of both localized and systemic diseases. In this article we review the various approaches used to enhance and control the delivery of protein therapeutic agents through the dermal barrier. We show results of the delivery of interferon (IFN) alpha, an antiviral agent used in the treatment of condylomata acuminata (genital warts), using lipid-based delivery systems (LBDS). In the general category of LBDS, we investigated the use of liposomes and fatty acylation as ways to increase IFNalpha delivery into human skin.

The struck-off mystery

Observations on ward rounds suggested that psychiatric patients might be at special risk of removal from their general practitioner's list. Little has been published on why patients are struck off and our first attempt at investigation was by direct appeals for patients. This drew a small and unsatisfactory sample. We then asked two family health services authorities to distribute questionnaires to struck-off patients. One agreed, but later withdrew cooperation. There is a danger that struck-off patients will become an underclass excluded from primary care. We propose anonymous collection of information by health authorities, so that policy can be reviewed if necessary.

Progress with the HeartSaver Ventricular Assist Device

BACKGROUND

Ventricular assist devices (VADs) have been shown to be effective for short- or long-term circulatory support. Devices are either being adapted or newly designed for longer term or permanent support, with the goal to provide patients with improved quality of life. Since 1990, a program has been in place to develop a totally implantable, permanent VAD.

METHODS

A multidisciplinary team is developing this VAD with specific goals in mind: (1) that it have an intrathoracic position, (2) that it be a totally implantable device without any percutaneous connections, and (3) that it be possible to communicate with the device from remote locations. These goals would allow for complete patient mobility and flexibility for follow-up.

RESULTS

The electrohydraulically actuated VAD combines the blood pump, volume displacement chamber, energy converter, and internal electronic module into a single compact unit. The device called the HeartSaver VAD is powered by a transcutaneous energy transfer system and can be remotely monitored and controlled. Prototypes of different versions of the device have been tested in vitro and in vivo with satisfactory performance.

CONCLUSIONS

The prototypes of the HeartSaver VAD have functioned well under test conditions and fulfilled the outlined goals. Further development and testing of the design are being conducted before clinical availability.

British psychiatry and homosexuality

BACKGROUND

Opposition to homosexuality in Europe reached a crescendo in the 19th century. What had earlier been regarded as a vice evolved as a perversion or psychological illness. Official reviews of homosexuality as both an illness and (for men) a crime led to discrimination, inhumane treatments and shame, guilt and fear for gay men and lesbians. Only recently has homosexuality been removed from all international diagnostic glossaries.

AIMS

To review how British psychiatry has regarded homosexuality over the past century.

METHOD

Review of key publications on homosexuality in British psychiatry.

RESULTS

The literature on homosexuality reflects evolving theories on sexuality over the past century. The assumptions in psychoanalysis and the behavioural sciences that sexuality could be altered led to unscientific theory and practice.

CONCLUSIONS

Mental health professionals in Britain should be aware of the mistakes of the past. Only in that way can we prevent future excesses and heal the gulf between gay and lesbian patients and their psychiatrists.

Ethnicity and outcome of psychosis

BACKGROUND

An excess of psychotic illness in Black people has been found in cross-sectional studies. Little is known about the outcome of psychosis in different ethnic groups in the UK.

AIMS

To compare the incidence, nature and long-term outcome of psychosis in different ethnic groups.

METHOD

A five-year, prospective study of an epidemiological cohort of people with a first contact for psychosis.

RESULTS

Age-standardised incidence rates for schizophrenia and non-affective psychosis were higher for Black and Asian people than Whites. Stability of diagnosis and course of illness were similar in all ethnic groups. During the fifth year, Black people were more likely than others to be detained, brought to hospital by the police and given emergency injections.

CONCLUSIONS

The nature and outcome of psychotic illness is similar in all ethnic groups but Black people experience more adverse contacts with services later in the course of illness.

Effect of aerosolized uridine-5'-triphosphate on airway clearance with cough in patients with primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a genetic disease characterized by abnormal ciliary structure and function and impaired mucociliary clearance. Because patients with PCD use cough clearance as an airway defense mechanism, we tested the hypothesis that aerosolized uridine-5'-triphosphate (UTP) would improve clearance during cough by its actions to stimulate Cl- secretion and mucin release by goblet cells. We measured clearance during cough in 12 patients with PCD (ages 14 to 71 yr, FEV1 43% to 89% predicted) in a double blind, randomized, crossover study after aerosolization of a single dose of UTP (5 mg/ml, 3.5 ml) or vehicle (0.12% saline, 3.5 ml). Clearance during cough (whole lung) was quantified during and after a series of controlled coughs by measuring the clearance of [99mTc]Fe2O3 particles via gamma camera scanning over 120 min. Safety parameters were recorded during and after drug delivery. Aerosolized UTP improved whole-lung clearance during cough as compared with vehicle (from 0 to 60 min: 0.40 +/- 0.07%/min [UTP] versus 0.26 +/- 0. 04%/min [vehicle] [mean +/- SEM], p = 0.01), and from 0 to 120 min: 0.38 +/- 0.05%/min [UTP] versus 0.25 +/- 0.04%/ min [vehicle], p = 0. 02). Aerosolized UTP is safe, with no serious adverse effects. Whole-lung clearance during cough in patients with defective ciliary function is enhanced after inhalation of UTP.

Successful treatment of severe muscle necrosis with intravenous immunoglobulin

Intravenous immunoglobulin (IVIG) is an effective treatment for a range of conditions believed to have an autoimmune basis, including inflammatory muscle disease. We describe a patient with muscle disease characterized by severe necrosis without clinical or biopsy evidence of inflammation or vasculitis, who responded to treatment with IVIG.