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Biomedical subjects

S Noble

Publications and source records attributed to S Noble.

At least 73 records · Page 4Linked to original sources

Saquinavir. A review of its pharmacology and clinical potential in the management of HIV infection.

Saquinavir is a peptide derivative which inhibits the HIV protease enzyme, preventing post-translational processing of viral polyproteins. It was the first agent of its class to become available for the treatment of HIV infection. Well controlled studies have assessed the effects of saquinavir, when used alone or in combination with reverse transcriptase inhibitors, in patients with advanced HIV infection. Analysis of CD4+ cell counts and measures of viral load in the ACTG 229 study suggest that triple therapy with saquinavir, zidovudine and zalcitabine is more effective than double therapy with saquinavir plus zidovudine or zidovudine plus zalcitabine in patients who have previously received long term treatment with zidovudine. Similar assessments from a small study in previously untreated patients suggest that double therapy with saquinavir plus zidovudine is more effective than monotherapy with either agent. Combination therapy with saquinavir and zalcitabine significantly reduced the time to the first AIDS-defining event or death, and the time to death, compared with zalcitabine alone, according to data from a large, long term study (NV 14256) in patients with advanced HIV infection who had previously received zidovudine. Saquinavir is generally well tolerated, either as monotherapy or in combination with reverse transcriptase inhibitors; no change in tolerability profile was reported when saquinavir was added to treatment with nucleoside analogues. In vitro and clinical studies have documented the emergence of saquinavir-resistant HIV strains. Although the possible impact of resistance on the clinical efficacy of saquinavir has yet to be fully characterised, genotypic and phenotypic resistance appear to develop slowly during treatment with saquinavir, and the drug does not appear to have a significant effect on the incidence of mutations associated with cross-resistance to other protease inhibitors. Thus, laboratory and clinical results suggest that saquinavir in combination with reverse transcriptase inhibitors is effective in the treatment of advanced HIV infection. Initial data on the effects of saquinavir on disease progression and mortality are promising, and the apparent absence of mutations conferring cross-resistance to other protease inhibitors is a potentially valuable clinical feature. Additional data on disease progression, mortality and viral resistance, together with information on relative efficacy (in comparison with other protease inhibitors), will need to be assessed before the clinical value of saquinavir can be fully determined. Nevertheless, saquinavir represents a valuable new pharmacological option for the treatment of HIV infection and is likely to be a useful component of combined therapy with reverse transcriptase inhibitors and/or other protease inhibitors.

Anti-Bacterial Agents↗

Reteplase. A review of its pharmacological properties and clinical efficacy in the management of acute myocardial infarction.

Reteplase (BM 06.022; r-PA) is a recombinant peptide which consists of the kringle 2 and protease domains of human tissue-type plasminogen activator. It has been developed as a thrombolytic treatment for acute myocardial infarction (AMI). The half-life of reteplase allows administration as a double-bolus injection (second injection given 30 minutes after the first) rather than by the prolonged and, in some cases, more complex intravenous infusion regimens that are required for most other thrombolytic agents. Reteplase produced rapid and effective coronary artery thrombolysis in a number of dose-finding and comparative studies. Double-bolus administration of reteplase 10U + 10U produced significantly higher coronary artery patency rates than accelerated alteplase (100mg as a 1.5-hour infusion) in patients with AMI in the RAPID-II study. The 10U + 10U reteplase regimen produced a 35-day survival rate at least equivalent to that seen with a 1-hour infusion of streptokinase 1.5 million units in 5986 patients in the INJECT study, which was designed to demonstrate equivalence between treatments. As with other thrombolytics, bleeding was the most common adverse event seen in reteplase recipients. No significant differences in the overall risk of haemorrhage were observed between reteplase and either accelerated alteplase or standard streptokinase treatment in clinical trials. The risk of stroke in reteplase recipients appears to be similar to that for other thrombolytic agents [1.2% incidence in 3288 patients treated with reteplase 10U + 10U in clinical trials (0.76% for haemorrhagic stroke)], although accurate statistical assessment of the relative risk is not possible for the data available to date. Thus, reteplase is an effective thrombolytic agent which can be administered as a double-bolus injection regimen rather than as a prolonged infusion. Together with acquisition cost and general pharmacoeconomic data (which are not yet available), the results of GUSTO-III (a trial comparing double-bolus reteplase with accelerated alteplase in 15 000 patients) will have a major influence on the pattern of use of reteplase. In the meantime, data from the available clinical trials suggest that reteplase is a fast-acting and effective thrombolytic treatment for patients with AMI.

Animals↗

Erdosteine.

Erdosteine is a thiol derivative developed for the treatment of chronic obstructive bronchitis, including acute infective exacerbation of chronic bronchitis. Erdosteine contains 2 blocked sulfhydryl groups which are released following first-pass metabolism. The 3 active metabolites exhibit mucolytic and free radical scavenging activity. Erdosteine modulates mucus production and viscosity and increases mucociliary transport, thereby improving expectoration. It also exhibits inhibitory activity against the effects of free radicals produced by cigarette smoke. Clinical studies in patients with chronic obstructive lung disease have demonstrated the efficacy and tolerability of erdosteine. Erdosteine 300mg twice daily reduced cough (both frequency and severity) and sputum viscosity more quickly and more effectively than placebo and reduced the adhesivity of sputum more effectively than ambroxol 30mg twice daily. Co-administration of erdosteine and amoxicillin in patients with acute infective exacerbation of chronic bronchitis resulted in higher concentrations of the antibiotic in the sputum, leading to earlier and more pronounced amelioration of clinical symptoms compared with placebo. Erdosteine is associated with a low incidence of adverse events, most of which are gastrointestinal and generally mild.

Animals↗

Characterization of putative defective interfering (DI) A/WSN RNAs isolated from the lungs of mice protected from an otherwise lethal respiratory infection with influenza virus A/WSN (H1N1): a subset of the inoculum DI RNAs.

Defective interfering (DI) influenza virus A/WSN (H1N1) grown in embryonated eggs protected adult mice from a lethal respiratory infection with A/WSN virus. Eighteen bands of putative DI RNA, ranging in size from about 230 to 1020 nt, were identified in this preparation by reverse transcription and polymerase chain reaction using a segment-specific 3' primer and a segment-universal 5' primer. Every virion RNA segment was represented by one to four bands of putative DI RNA. However, only five bands of putative DI RNA could be isolated, using the same conditions, from lungs of WSN-infected mice protected from death by co-inoculation with egg-grown DI WSN. These five bands originated from PB1, PB2, PA, and M virion RNAs and were all about 350-450 nt in length. Four putative DI RNAs originating from PB1, PB2, and PA virion RNAs were sequenced, and three were identical (including deletion junctions and base substitutions) to putative DI RNAs from the inoculum. These data suggest that the mouse lung was highly selective for a subset of inoculum DI RNAs and that one or more of these DI RNAs was responsible for protection in vivo. All putative DI RNAs had a single internal deletion.

Animals↗

Tretinoin. A review of its pharmacological properties and clinical efficacy in the topical treatment of photodamaged skin.

Tretinoin (all-trans-retinoic acid) is a retinol (vitamin A) derivative which has been evaluated as a topical treatment for the symptoms of photodamaged skin. In several well-controlled clinical trials, the proportion of patients showing improvement was significantly higher with 0.01 or 0.05% tretinoin cream than with placebo for criteria such as global assessment, fine and coarse wrinkling, pigmentation and roughness. Improvements in the overall severity of photodamage were also significantly greater with tretinoin than with placebo. The extent of clinical improvement with tretinoin has generally been moderate, but cytological and histological studies have shown that extensive changes in the epidermis and dermis occur during treatment. However, the permanency and clinical significance of these changes has yet to be fully evaluated. Topical tretinoin has also demonstrated potential for the treatment and eradication of premalignant skin growths such as actinic keratoses, and may be useful as combination therapy with fluorouracil in this indication. Dermatitis (the retinoid skin reaction) is the most common adverse event experienced by patients receiving topical tretinoin; this condition may persist for up to 3 months, but is usually mild or moderate in nature. Thus, topical tretinoin has been shown to be an effective form of treatment for the characteristic signs of photodamaged skin. Its ability to produce significant, albeit moderate, clinical improvements in symptoms such as fine wrinkling, roughness and pigmentation, together with its relatively mild or moderate adverse event profile, suggests that it is likely to be of considerable value in this indication. The treatment and eradication of potentially malignant growths such as actinic keratoses may also prove to be an important application for topical tretinoin.

Administration, Topical↗

Enoxaparin. A reappraisal of its pharmacology and clinical applications in the prevention and treatment of thromboembolic disease.

Enoxaparin (enoxaparin sodium) is a low molecular weight derivative of unfractionated heparin which has been evaluated for the treatment and prevention of thromboembolic disease. Since a previous review in Drugs, well controlled clinical trials have confirmed the effectiveness of enoxaparin as prophylaxis in patients with a high risk for deep venous thrombosis (DVT), i.e. those undergoing hip or knee replacement surgery. Enoxaparin 30mg twice daily, initiated postoperatively, offers an overall balance of prophylactic efficacy and haemorrhagic tolerability which is superior to that of unfractionated heparin. In comparative clinical trials, this dosage demonstrated either improved efficacy and a similar haemorrhagic profile, or a similar degree of efficacy with a lower rate of haemorrhagic events, compared with unfractionated heparin 5000IU 3 times daily. Limited data indicate that an enoxaparin regimen of 40mg once daily, starting preoperatively, is more effective than unfractionated heparin in patients undergoing hip replacement and has a comparable haemorrhagic profile. In patients with a moderate risk for DVT, enoxaparin is similar to unfractionated heparin in both efficacy and haemorrhagic profile, while preliminary investigations have demonstrated the utility of enoxaparin in the prevention of DVT in elderly, nonsurgical patients. Enoxaparin may also be useful for the treatment of existing DVT and as an anticoagulant in haemodialysis. Thus, enoxaparin is an effective form of prophylaxis for thromboembolic disease in moderate to high risk surgical situations. Recent evidence for improved efficacy, together with a similar incidence of haemorrhagic complications in most situations, may lead to enoxaparin being preferred to unfractionated heparin for the routine prevention of DVT after high risk surgery. Although detailed comparisons with other low molecular weight heparins and antithrombotic agents are required before its relative clinical utility can be fully assessed, enoxaparin is likely to play a significant role in the prophylaxis of thromboembolic disorders.

Biological Availability↗

Spirapril. A preliminary review of its pharmacology and therapeutic efficacy in the treatment of hypertension.

Spirapril is a non-sulfhydryl angiotensin converting enzyme (ACE) inhibitor prodrug which is converted to the active metabolite spiraprilat following oral administration, and which has been evaluated primarily for the treatment of hypertension. In dose-finding studies of patients with mild to severe hypertension, spirapril > or = 6 mg once daily produced reductions in blood pressure of approximately 10 to 18 mm Hg (systolic) and 7 to 13 mm Hg (diastolic) [24-hour postdose trough readings at the end of the treatment period]. Blood pressure normalisation (trough diastolic blood pressure < or = 90 mm Hg) had occurred in 29 to 50% of patients at the end of these investigations. The dose-response curve for spirapril appears to be flat for doses of 6 to 24 mg once daily. Comparisons with other ACE inhibitors are limited in number, and further studies are required before the relative antihypertensive efficacy of spirapril can be fully evaluated. However, in single, well controlled clinical trials, spirapril produced similar reductions in blood pressure to those seen with enalapril or captopril. When given as monotherapy or in combination with hydrochlorothiazide, spirapril may offer potential advantages over the calcium antagonist nitrendipine. Spirapril is generally well tolerated and produces an adverse event profile similar to that of other ACE inhibitors. Data from small studies suggest that spirapril can be used without dosage adjustment in patients with renal impairment, as a consequence of its dual renal and hepatic clearance mechanisms. This is in contrast to most ACE inhibitors, which are eliminated by a predominantly renal mechanism that results in accumulation of the active metabolite when renal function is impaired. However, the utility of spirapril in this patient group has yet to be fully determined because of conflicting data regarding its effects on renal function. Thus, spirapril is an effective antihypertensive agent which is well tolerated. Further comparative trials are needed to fully determine its efficacy with respect to other ACE inhibitors, and a better understanding of its effects on renal function will clarify its role in hypertensive patients with renal failure.

Angiotensin-Converting Enzyme Inhibitors↗

Sulfasalazine. A review of its pharmacological properties and therapeutic efficacy in the treatment of rheumatoid arthritis.

Sulfasalazine was first used for rheumatic polyarthritis in the 1940s and in the past 2 decades has become firmly established as a disease-modifying antirheumatic drug (DMARD). The drug is split by the action of bacterial azoreductases in the large intestine into sulfapyridine and mesalazine (mesalamine, 5-aminosalicylic acid), although whether the parent molecule or the sulfapyridine moiety, or both, is the active principle remains uncertain. Sulfasalazine is an effective treatment for rheumatoid arthritis (RA), producing improvements in disease parameters similar to those seen with penicillamine, hydroxychloroquine or oral or parenteral gold in comparative clinical trials. However, there are no direct comparisons of the drug with methotrexate. Most adverse events associated with sulfasalazine are minor and tend to occur within 3 months of starting therapy. A meta-analysis of studies investigating DMARD therapy, which included almost 5000 evaluable patients, concluded that sulfasalazine was close to methotrexate in terms of efficacy but was slightly less well tolerated. However, unlike sulfasalazine, many DMARDs may be unsuitable for women who are, or may become, pregnant because of their potential to cause teratogenic effects. Sulfasalazine may also offer a more rapid onset of action than other DMARDs and may slow down the radiological progression of RA. Combination therapy with other DMARDs, particularly methotrexate, appears more effective than single DMARD therapy. If the safety of these regimens is shown in large numbers of patients they are likely to become more widely used in the future. Sulfasalazine is a therapy of first choice in patients with RA and may be the DMARD of choice in women who are, or may become, pregnant.

Antirheumatic Agents↗

Cyclosporin. A review of the pharmacokinetic properties, clinical efficacy and tolerability of a microemulsion-based formulation (Neoral).

The microemulsion-based formulation of cyclosporin (Neoral; referred to as the microemulsion formulation in this review) is a microemulsion preconcentrate which has been developed to overcome problems associated with the poor and unpredictable absorption of the standard oral formulation of this drug. These include marked intra- and interpatient variability in the extent of absorption, a poor correlation between trough blood concentrations of cyclosporin and total systemic exposure, and the need for regular monitoring of blood cyclosporin concentrations. In healthy volunteers and renal or liver transplant recipients, administration of the microemulsion formulation resulted in cyclosporin absorption which was significantly faster, more extensive and more predictable than that seen with the standard oral formulation. Furthermore, measurement of whole-blood trough cyclosporin concentrations provided a better estimate of systemic drug exposure in renal transplant recipients who received the microemulsion formulation than in those who received the standard formulation. Systemic exposure of cyclosporin delivered by the new formulation appears to be relatively unaffected by food intake. Initial data suggest that drug absorption from the microemulsion formulation is enhanced in comparison with that achieved from the standard formulation in liver transplant recipients undergoing biliary diversion or with cholestasis, although absorption from the new formulation does not appear to be completely independent of bile. Preliminary results from other groups that experience cyclosporin malabsorption from the standard formulation (patients with cystic fibrosis or diabetes, and children) are also encouraging. Clinical trials specifically designed to investigate the relative immunosuppressive efficacy of the microemulsion formulation have not been reported; further data are required to fully establish the relationship between the more rapid and extensive absorption of cyclosporin from the microemulsion formulation and the probability of graft rejection or adverse events (including nephrotoxicity and hypertension). However, no statistically significant differences have been noted between the 2 formulations in the incidence of these events in studies to date. The incidence of rejection in new renal or liver transplant recipients treated for a minimum of 3 months was approximately 31 to 50% in those receiving the microemulsion formulation and approximately 24 to 56% in those receiving the standard formulation. Thus, although confirmation of existing efficacy and tolerability data is required, the characteristic pharmacokinetic properties of the microemulsion formulation make it an attractive option for the oral delivery of cyclosporin in transplant recipients, offering more predictable and more extensive drug absorption than the standard formulation. The microemulsion formulation may be of particular benefit in patients who show poor absorption of cyclosporin from the standard oral formulation, such as liver transplant recipients with biliary diversion or cholestasis.

Animals↗

Levocabastine. An update of its pharmacology, clinical efficacy and tolerability in the topical treatment of allergic rhinitis and conjunctivitis.

Levocabastine is a potent and selective histamine H1-receptor antagonist which has been evaluated as a topical treatment (nasal spray and/or eyedrops) for allergic rhinitis and/or conjunctivitis. Data available at the time of the previous review in Drugs, together with more recent results, have clearly demonstrated that levocabastine nasal spray and eyedrops are clinically effective, have a rapid onset of action and are well tolerated in patients with nasal and/or ocular allergic conditions. Previous evidence indicating that topical levocabastine has efficacy similar to or better than that of topical sodium cromoglycate (cromolyn sodium) has been confirmed in more recent studies. Furthermore, results from a number of controlled clinical trials have also shown that topical levocabastine is at least as effective as oral terfenadine for the treatment of allergic rhinoconjunctivitis. Notably, topical levocabastine appears to be more effective than oral terfenadine in improving the severity of selected symptoms. Limited data indicating efficacy equivalent to that of oral loratadine, oral cetirizine or azelastine nasal spray will need to be confirmed. Data from several studies have shown that topical levocabastine has a tolerability profile similar to that of placebo, topical sodium cromoglycate or oral terfenadine. The main adverse events seen in patients treated with topical levocabastine are ocular irritation after application of eyedrops, and headache, nasal irritation, somnolence and fatigue after administration of the nasal spray. Administered doses of topical levocabastine, and subsequent plasma concentrations, are low, and the risk of systemic adverse events is therefore expected to be minimal. Thus, topical administration of levocabastine rapid and effective symptom relief with no apparent serious adverse events in patients with allergic rhinitis and/or conjunctivitis. Topical levocabastine is a useful alternative to topical sodium cromoglycate or oral terfenadine. Additional data supporting current evidence that topical levocabastine can provide more effective symptom relief than oral terfenadine, together with clarification of the relative efficacies of these agents in relation to varying pollen exposure, would help to further confirm its clinical potential. However, the results available to date suggest that the topical formulations of levocabastine are a valuable treatment option in patients with allergic rhinitis and/or conjunctivitis.

Aerosols↗

Defective interfering type A equine influenza virus (H3N8) protects mice from morbidity and mortality caused by homologous and heterologous subtypes of influenza A virus.

Intranasal administration of defective interfering A/equine/Newmarket/7339/79 (H3N8) influenza virus (DI EQV) protected mice from otherwise lethal intranasal infection with homologous virus (EQV) or with the heterologous subtypes A/WSN (H1N1) or A/PR/8/34 (H1N1). Such protected mice showed little or no sign of clinical disease. Disease with only low mortality resulting from a 'low' dose of WSN was completely prevented with a 100-fold lower dose of DI EQV (4 haemagglutinating units/ml or 12 ng virus/mouse), indicating that there was a roughly proportional relationship between the protective dose of DI virus and the infecting inoculum. DI EQV-protected mice continued to gain weight at the normal rate, whereas those treated with inactivated DI EQV ceased putting on weight for about 7 days and were still underweight nearly 3 weeks later. Unlike DI WSN, DI EQV inhibited multiplication of infectious WSN in the lungs by 20 to 60-fold. Intranasal DI EQV on its own gave little protection to mice challenged 24 days later with EQV suggesting that it was only weakly immunogenic. DI EQV afforded significant protection when given up to 5 days before live virus challenge indicating that the DI genome remained active in the respiratory tract for this period of time.

Animals↗

General practice fundholding: observations on prescribing patterns and costs using the defined daily dose method.

OBJECTIVE: To compare prescribing patterns between a group of fundholding practices and a group of non-fundholding practices in north east Scotland using a method which provides more accurate statements about volumes prescribed than standard NHS statistics. DESIGN: The pharmacy practice division of the National Health Service in Scotland provided data for selected British National Formulary sections over two years. Each prescription issued was converted using the World Health Organisation "defined daily dose" mechanism. SETTING: Six fundholding groups (nine practices) in Grampian and Tayside regions and six non-fundholding practices in Grampian. RESULTS: During the past two years both fundholding and control practices reduced the volume of their prescribing for the classes of drug analysed. The unit costs of drugs in some classes, however, rose substantially, contributing to higher costs per patient. The unit costs rose more in the control practices (24%) than in the fundholding practices (11% in Tayside, 16% in Grampian). CONCLUSION: The use of defined daily doses helped identify cost and volume trends in specific areas of prescribing in fundholding and control practices. The basis on which funds are set needs improving, and defined daily doses may prove useful for setting volume targets within drug classes for all practices, whether fundholding or not.

Age Factors↗

Antigenic and genetic conservation of the haemagglutinin in H1N1 swine influenza viruses.

We examined the level of antigenic conservation amongst the haemagglutinins (HAs) of H1 swine influenza viruses, recently isolated from a wide geographical area, in haemagglutination inhibition assays against a panel of four monoclonal antibodies (MAbs). We found a high degree of conservation with a dominant variant (52 of 54 isolates) that reacted with all MAbs. Only two minor variants, each failing to react with one MAb, were found. Using a one-step PCR technique followed by direct sequencing of the products, we examined the HA1 region of the HA RNA of two representative dominant variants. We found no amino acid substitutions relative to a reference strain. The sequences of the HA1 RNA of the two minor variants isolated here and of two other minor variants defined previously were also determined. Each contained inferred amino acid substitutions, all located at different positions on the HA. Finally, we sequenced HA1 RNA obtained from the original pig lung suspensions from which the two dominant and two minor variants had been isolated. Three of the parent viruses were identical to their progeny in eggs whereas the fourth parent virus contained four amino acid differences from its progeny.

Antibodies, Monoclonal↗

Structure of the pinworm (Oxyurida: Nematoda) guild in the hindgut of the American cockroach, Periplaneta americana.

The pinworm (Oxyurida: Nematoda) guild in a laboratory colony of Periplaneta americana was investigated to answer the following questions. (1) Is guild structure stable with time? (2) Is there evidence of interaction among the species? (3) Is there evidence for niche diversification with respect to spatial distribution or developmental stage of host? Four species were found: Thelastoma periplaneticola, Thelastoma bulhoesi, Hammerschmidtiella diesingi and Leidynema appendiculatum; females of the first two could not be distinguished and they were lumped and referred to as Thelastoma sp.; 328 mid-instar hosts were dissected between September 1987 and February 1990, and the number of adult females of each pinworm species was recorded to investigate changes in guild structure through time. Seventy-five percent of hosts had Thelastoma sp., 62% had H. diesingi and 40% had L. appendiculatum; mean intensities were 6.5 (Thelastoma), 2.9 (H. diesingi) and 1.9 (L. appendiculatum). Relative numbers were stable with time and intensities of the species were similar whether they occurred alone in the host or in conjunction with other species. Thelastoma sp. and L. appendiculatum occurred together less often than expected and their numbers in individual hosts were negatively correlated. Both species occurred alone more often than expected. Surprisingly, H. diesingi and L. appendiculatum occurred together more often than expected. Intestines of 44 roaches were frozen in liquid nitrogen and divided into 5 equal sections to study longitudinal distributions of the species in the gut. Most L. appendiculatum and H. diesingi were found in the first, whereas most Thelastoma sp. occurred in the second segment. However, Thelastoma sp. dominated all segments of the gut. Worms were counted in 192 hosts belonging to 4 categories (early instar, late instar, adult male and adult female). Single species infections were more common in early instar hosts but there was no evidence that different species preferred different host stages. Modal distributions in male L. appendiculatum and T. bulhoesi suggest that these species may exhibit intraspecific interference competition similar to that observed in other pinworms. Such effects may be more important than interspecific effects in maintaining guild stability.

Animals↗

Transmission pattern and intraspecific competition as determinants of population structure in pinworms (Oxyurida: Nematoda).

The transmission pattern of Zonothrix columbianus (Nematoda: Oxyurida) in its host Tropisternus columbianus (Coleoptera: Hydrophilidae), an aquatic beetle, was studied to determine whether parasites were dispersed with their hosts and to examine the possible role of intraspecific competition in limiting population size. Beetles were sampled at regular intervals from fall 1986 through fall 1989 and examined for worms. Worms, absent in larval stages of the host, were uncommon in newly metamorphosed beetles and therefore probably do not infect adult stages until after they have dispersed; worms are not dispersed with the host. Prevalence reached its lowest points in spring and fall when newly metamorphosed beetles were most common, but it was near 100% for most of the year. Worms were uniformly distributed in the host population. Many hosts had exactly 1 male and 1 female worm; the high prevalence suggests that this infrahost population results from interference competition between males on the one hand and females on the other. Only 3 of 285 beetles contained more than 1 male. Females shared the host with members of the same sex more commonly than males, but females from hosts harboring more than 1 female had significantly fewer eggs than lone females in hosts. Numbers of adult stages of beetles were estimated during spring, summer, and fall of 1989 and were lower in early spring and late fall. Because worms do not disperse with hosts, the panmictic unit could be estimated from the number of infected beetles; this probably was about 50 individuals during the winter bottleneck.

Analysis of Variance↗

House officer responses to impaired physicians.

Although physician impairment may have substantial personal and clinical consequences, it is commonly held that physicians fail to act in the case of impaired colleagues. To learn about initial responses when confronted with impaired house officers and attending physicians, we administered five case scenarios to all 76 internal medicine house officers at a large, urban, teaching hospital. House officer responses to an alcohol-impaired physician differed depending on whether that physician was an attending physician or a house officer. Seventy-two percent of house officers would tell the chief resident about the alcohol-impaired attending physician, whereas 96% would confront the alcohol-impaired house officer personally. The most common response to the incompetent attending physician (67%) and the incompetent house officer (49%) was to tell the chief resident; only 25% would confront an incompetent house officer. In contrast, 71% would confront a depressed house officer.

Attitude of Health Personnel↗