Minimal contribution of desmethyl-gefitinib, the major human plasma metabolite of gefitinib, to epidermal growth factor receptor (EGFR)-mediated tumour growth inhibition

Desmethyl-gefitinib is a major metabolite of gefitinib observed in human plasma at concentrations similar to those of gefitinib. The epidermal growth factor receptor (EGFR)-related inhibitory effects of gefitinib and desmethyl-gefitinib have been compared both in vitro, using enzyme kinase assays and tumour cell growth inhibition, and in vivo by assessment of tumour xenografts growth inhibition in the mouse. Both gefitinib (IC(50) = 0.022 microM) and its desmethyl metabolite (0.036 microM) inhibited subcellular EGFR tyrosine kinase activity with a similar potency and selectivity. However, desmethyl-gefitinib (IC(50) = 0.76 microM) was 15 times less active than gefitinib (0.049 microM) against EGF-stimulated KB cell growth in a whole cell assay. Following a preliminary pharmacokinetic study to compare apparent oral bioavailability, gefitinib (75 mg kg(-1)) and desmethyl-gefitinib (150 mg kg(-1)) were administered orally for 15 days to female nude mice bearing LoVo tumour xenografts. Tumour concentrations of gefitinib (AUC = 300 microg h g(-1)) were much higher than those of desmethyl-gefitinib (44.3 microg h g(-1)), although plasma concentrations of gefitinib (48.4 microg h ml(-1)) and desmethyl-gefitinib (39.0 microg h ml(-1)) were quite similar at these dose levels. Gefitinib produced significant tumour growth inhibition throughout the course of the study ultimately resulting in a 50% decrease (compared with controls) by day 15. In contrast, although present at comparable plasma levels, desmethyl-gefitinib had little effect on tumour growth and is, therefore, considered unlikely to contribute significantly to the therapeutic activity of gefitinib in the clinical situation.

Efficacy of a single application of a 12.5% pyriprole topical solution against laboratory infestations with ticks (Ixodes ricinus, Dermacentor reticulatus, and Rhipicephalus sanguineus) on dogs

In three separate studies, the efficacy of a single treatment with a 12.5% pyriprole spot-on solution was investigated against induced infestation with Ixodes ricinus, Dermacentor reticulatus and Rhipicephalus sanguineus on dogs (both sexes; Beagles in Studies 1 and 2, mixed-breed in Study 3). For each tick species, one group of 8 dogs left untreated (Studies 1 and 2) or treated with a placebo solution (Study 3) was compared with another group treated once with the spot-on solution at a dose rate of at least 12.5mg/kg. The dogs were infested with 50 unfed adult ticks of the respective species at various time-points before and after treatment and the surviving attached and unattached ticks were recorded 48 h after re-infestation. For each tick species, efficacy was assessed for each time-point and cumulatively for the whole evaluation period. The dogs were submitted to general health observations and clinical assessments during the study. Efficacy against I. ricinus and R. sanguineus was 100% during the whole evaluation period of 30 days. For D. reticulatus cumulative efficacy for the 30 days after treatment was 98.9%. The product was well tolerated by all the animals.

Efficacy of pyriprole topical solution against the cat flea, Ctenocephalides felis, on dogs

Three studies evaluating various aspects of the performance of pyriprole against the cat flea, Ctenocephalides felis, on dogs demonstrated that 12.5% pyriprole applied as a spot-on provides rapid, long-lasting efficacy against adult cat fleas, even under severe flea challenge. Speed of kill data indicate treatment with this product can interrupt an already established adult flea infestation, whereas monthly treatment can prevent reinfestation. Pyriprole disrupts the flea life cycle by killing adult fleas before they lay eggs for at least 30 days after treatment. The residual effect of pyriprole on debris from treated dogs (dander, hair, scales, and flea feces) resulted in a decreased ability of cat flea larvae to complete development to the adult stage for 2 weeks after application. Based on the results of these studies, 12.5% pyriprole represents a valuable new tool in the control of the cat flea, C. felis, on dogs.

The effect of water and shampooing on the efficacy of a pyriprole 12.5% topical solution against brown dog tick (Rhipicephalus sanguineus) and cat flea (Ctenocephalides felis) infestations on dogs

The efficacy of a single treatment with a 12.5% pyriprole spot-on formulation against induced infestations with R. sanguineus ticks and cat fleas (C. felis) as well as its persistence after repeated washing and shampooing was investigated in four separate studies. In a first study on R. sanguineus involving 32 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation ranged from 100% to 99.3%. No engorged ticks, alive or dead, were found in the treated animals. Shampooing 2 days after treatment and weekly washings did not affect the efficacy. In a second study on R. sanguineus involving 32 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation ranged from 100% to 96.8%. Single washing 8h after treatment and single shampooing 24 h after treatment had no negative impact on the efficacy of the product. In a third study on C. felis involving 28 beagle dogs, the efficacy at various time-points during the 30 days that followed treatment assessed 48 h after re-infestation was always 100% and weekly washings did not diminish the efficacy. In a last study on C. felis involving 24 beagle dogs, the efficacy at various time-points during the 5 weeks that followed treatment assessed 48 h after re-infestation ranged from 100% to 99.8%, and shampooing 24 h after treatment did not reduce the efficacy. The product was well tolerated by the dogs.

Comparison of intranasal with targeted lymph node immunization using PR8-Flu ISCOM adjuvanted HIV antigens in macaques

The rapidly spreading HIV epidemic requires a vaccine that elicits potent mucosal immunity to halt or slow transmission. Induction of these responses will depend on the use of appropriate adjuvants and targeting of the mucosal immune system. Previously, immune stimulating complexes (ISCOM) have shown great potency as adjuvant in the induction of mucosal responses in mice and systemic responses in non-human primates. In this study, HIV formulated in PR8-Flu ISCOM adjuvant was applied to immunize rhesus macaques against HIV; targeting the mucosa either via intranasal (IN) application or via targeted lymph node immunization (TLNI). While, strong systemic, HIV specific, cytokine, lymphoproliferative, and antibody responses were induced via the TLNI route, the IN application generated only low responses. Furthermore, all four animals immunized via TLNI developed vaginal IgA antibodies against gp120. In conclusion, in contrast to what has been demonstrated in mice, the IN application of PR8-Flu ISCOM did not induce strong immune responses in rhesus macaques unlike those immunized by the TLNI route.

Maternal and newborn-care practices during pregnancy, childbirth, and the postnatal period: a comparison in three rural districts in Bangladesh

The aim of this study was to examine the prevalence of maternal and newborn-care practices among women reporting a birth in the previous year in three districts in different divisions of Bangladesh. In 2003, 6,785 women, who had delivered a newborn infant in the previous year, across three districts in Bangladesh, were interviewed. Overall, less than half of the women received any antenatal care, and 11% received a minimum of four check-ups. Only 18% took iron tablets for at least four months during pregnancy. Over 90% of the 6,785 deliveries took place at home, and only 11% were attended either by a doctor or by a nurse. The mothers reported three key hygienic practices in 54% of deliveries: attendants washing their hands with soap and boiling cord-tie and blade for cutting the cord. Forty-four percent of the 6,785 infants were bathed immediately after delivery, and 42% were given colostrum as their first food. The results suggest that maternal and newborn-care remains a cause of concern in rural Bangladesh. Short-term policies to promote healthy behaviour in the home are needed, in addition to the long-term goal of skilled birth attendance.

Touch detection of neonatal hypothermia in Nepal

The use of touch by health workers to detect hypothermia was examined in 250 newborns in Nepal. Palpation of the feet shows fair interobserver agreement (kappa = 0.4-0.7) and high sensitivity (>80%) but low specificity (36%-74%) compared with axillary thermometry. Traditional birth attendants should feel an infant's feet to detect hypothermia.

Health care system accessibility. Experiences and perceptions of deaf people

BACKGROUND

People who are deaf use health care services differently than the general population; little research has been carried out to understand the reasons.

OBJECTIVE

To better understand the health care experiences of deaf people who communicate in American Sign Language.

DESIGN

Qualitative analyses of focus group discussions in 3 U.S. cities.

PARTICIPANTS

Ninety-one deaf adults who communicate primarily in American Sign Language.

MEASUREMENTS

We collected information about health care communication and perceptions of clinicians' attitudes. We elicited stories of both positive and negative encounters, as well as recommendations for improving health care.

RESULTS

Communication difficulties were ubiquitous. Fear, mistrust, and frustration were prominent in participants' descriptions of health care encounters. Positive experiences were characterized by the presence of medically experienced certified interpreters, health care practitioners with sign language skills, and practitioners who made an effort to improve communication. Many participants acknowledged limited knowledge of their legal rights and did not advocate for themselves. Some participants believed that health care practitioners should learn more about sociocultural aspects of deafness.

CONCLUSIONS

Deaf people report difficulties using health care services. Physicians can facilitate change to improve this. Future research should explore the perspective of clinicians when working with deaf people, ways to improve communication, and the impact of programs that teach deaf people self-advocacy skills and about their legal rights.

Racial disparity in surgical complications in New York State

OBJECTIVE

To examine the relationship between race and surgical complications.

SUMMARY BACKGROUND DATA

Blacks have been reported to experience higher rates of surgical complications than whites, but the reasons are not known.

METHODS

The effect of the black race on risk of any surgical complication (from the Agency for Healthcare Research and Quality's patient safety indicators) was examined using New York State (NYS) hospital discharge data from 1998 to 2000. Sequential, hierarchical analyses controlled for: 1) patient age and gender, 2) morbidity length of stay, 3) individual social factors, 4) hospital characteristics, and 5) ecologic factors (region of state, percent black and Medicaid annual discharges, and mean income of admitted patients).

RESULTS

Following adjustment for patient age and gender, blacks had 65% higher odds for a surgical complication. Further adjustment for comorbidity and length of stay (LOS) reduced the odds substantially to 1.18. Additional adjustment for American Hospital Association hospital characteristics essentially eliminated the risk. Final adjustment for hospital ecologic variables reduced the odds to 1.0.

CONCLUSIONS

Higher rates of surgical complications among blacks than whites in NYS are primarily explained by differences in comorbidity LOS and the hospital where the surgery occurred.

Body shape and composition in HIV-infected women: an urban cohort

OBJECTIVES

Alterations in body shape and composition are associated with HIV/AIDS. Wasting remains prevalent; increasingly, lipodystrophy is reported. Obesity is also epidemic in the USA. In this study, we sought to characterize the body changes reported by women attending a US urban clinic, and to evaluate contributing factors using inexpensive methods that are readily available in clinical practice.

METHODS

In an urban Maryland clinic, a cross-section of HIV-infected women were evaluated by self report, anthropomorphic measurements, bioelectric impedance analysis (BIA) and chart review; they were categorized as no change, lipodystrophy, weight loss/wasting or weight gain/obesity.

RESULTS

One hundred and sixty-one women were evaluated: 144 (89%) were African-American; 100 (62%) had used intravenous drugs and 40 (25%) were actively injecting drugs, while 39 (24%) smoked crack. Ninety-five (59%) were on highly active antiretroviral therapy (HAART) for a median period of 11.7 months [interquartile range (IQR)=4.5-24.2]. Since starting current HAART or in the previous year, 12 (7.4%) reported lipodystrophy changes, 85 (52.8%) weight gain, 27 (16.8%) overall weight loss, and 37 (23.0%) no change. Lipodystrophy was associated with higher CD4 percentage (P=0.03), lower frequency of crack use (P=0.04) and higher educational level (P=0.03). Weight loss correlated with longer duration of infection (P=0.01), select BIA results and increased rate of crack use (P=0.005). Weight gain was associated with higher fat mass (P=0.005), higher peak viral load (P=0.02), and lower rate of intravenous drug use (P=0.03).

CONCLUSIONS

Self-reported changes in body shape were common. Obesity and complications of illicit drug use were more prevalent than lipodystrophy in this inner-city population of HIV-positive women.

Advanced anodes for high-temperature fuel cells

Fuel cells will undoubtedly find widespread use in this new millennium in the conversion of chemical to electrical energy, as they offer very high efficiencies and have unique scalability in electricity-generation applications. The solid-oxide fuel cell (SOFC) is one of the most exciting of these energy technologies; it is an all-ceramic device that operates at temperatures in the range 500-1,000 degrees C. The SOFC offers certain advantages over lower temperature fuel cells, notably its ability to use carbon monoxide as a fuel rather than being poisoned by it, and the availability of high-grade exhaust heat for combined heat and power, or combined cycle gas-turbine applications. Although cost is clearly the most important barrier to widespread SOFC implementation, perhaps the most important technical barriers currently being addressed relate to the electrodes, particularly the fuel electrode or anode. In terms of mitigating global warming, the ability of the SOFC to use commonly available fuels at high efficiency, promises an effective and early reduction in carbon dioxide emissions, and hence is one of the lead new technologies for improving the environment. Here, we discuss recent developments of SOFC fuel electrodes that will enable the better use of readily available fuels.

Efficacy and longevity of nitenpyram against adult cat fleas (Siphonaptera: Pulicidae)

Nitenpyram (Capstar) is a fast acting, orally administered flea treatment that is absorbed into the blood of the host animal and is readily available for uptake by feeding fleas. We examined the efficacy of a single dose of nitenpyram against adult cat fleas, Ctenocephalides felis (Bouché), over several days. We recorded adult flea mortality and flea egg production on treated and untreated cats. Nitenpyram provided 100% kill of all fleas on the host at the time of treatment and for up to 24 h after treatment. Between 24 and 48 h after treatment, there was a 98.6% reduction in adult flea numbers. From 48 to 72 h, there was a 5% reduction in adult fleas. There was a 97% reduction and 95.2% reduction in the number of flea eggs collected from treated versus untreated animals during the first 48 h and from 48 to 72 h, respectively. In addition, we quantified three distinct behavioral responses of infested adult cats treated with nitenpyram to determine the extent of any immediate, overt behavioral responses in treated animals. A significant increase in scratching, biting, licking, and twitching occurred for 5 h. The biting and licking continued for 7 h after treatment. Administration of nitenpyram provides an effective mechanism to eliminate adult fleas from hosts for up to 48 h after treatment.

Interrelations between three proxies of health care need at the small area level: an urban/rural comparison

STUDY OBJECTIVE

To examine the relations between geographical variations in mortality, morbidity, and deprivation at the small area level in the south west of England and to assess whether these relations vary between urban and rural areas.

DESIGN

A geographically based cross sectional study using 1991 census data on premature limiting long term illness (LLTI) and socioeconomic characteristics, and 1991-1996 data on all cause premature mortality. The interrelations between the three widely used proxies of health care need are examined using correlation coefficients and scatterplots. The distribution of standardised LLTI residuals from a regression analysis on mortality are mapped and compared with the distribution of urban and rural areas. Multilevel Poisson modelling investigates whether customised deprivation profiles improve upon a generic deprivation index in explaining the spatial variation in morbidity and mortality after controlling for age and sex. These relations are examined separately for urban, fringe, and rural areas.

SETTING

Nine counties in the south west of England.

PARTICIPANTS

Those aged between 0-64 who reported having a LLTI in the 1991 census, and those who died during 1991-1996 aged 0-74.

MAIN RESULTS

Relations between both health outcomes and generic deprivation indices are stronger in urban than rural areas. The replacement of generic with customised indices is an improvement in all area types, especially for LLTI in rural areas. The relation between mortality and morbidity is stronger in urban than rural areas, with levels of LLTI appearing to be greater in rural areas than would be predicted from mortality rates. Despite the weak direct relations between mortality and morbidity, there are strong relations between the customised deprivation indices computed to predict these outcomes in all area types.

CONCLUSIONS

The improvement of the customised deprivation indices over the generic indices, and the similarity between the mortality and morbidity customised indices within area types highlights the importance of modelling urban and rural areas separately. Stronger relations between mortality and morbidity have been revealed at the local authority level in previous research providing empirical evidence that the inadequacy of mortality as a proxy for morbidity becomes more marked at lower levels of aggregation, especially in rural areas. Higher levels of LLTI than expected in rural areas may reflect different perceptions or differing patterns of illness. The stronger relations between the three proxies in urban than rural areas suggests that the choice of indicator will have less impact in urban than rural areas and strengthens the argument to develop better measures of health care need in rural areas.

Video-assisted thoracoscopic thymectomy for myasthenia gravis

BACKGROUND

Thymectomy is an effective, but radical therapy for myasthenia. Video-assisted thoracic surgery (VATS) may allow a minimally invasive alternative to the standard sternotomy approach.

AIMS

To audit prospectively the outcome of VATS thymectomy for myasthenia gravis in a unit specializing in advanced VATS techniques.

METHODS

Twenty-six patients underwent VATS thymectomy between 1997 and 2001. Most underwent preoperative plasma exchange therapy. Seventeen women and nine men with a median age of 36 years (range 17-71 years) had a right-sided VATS approach to remove all anterior mediastinal fat and thymic tissue.

RESULTS

There was no perioperative mortality and all procedures were concluded successfully, with one patient requiring sternotomy. Twenty-five patients were extubated in theatre and one patient required 17 h of assisted ventilation. The other significant complication was a diathermy injury to the phrenic nerve, which recovered. Median postoperative stay was 4 days (range 2-6 days), with median postoperative chest drainage for 2 days (range 1-3 days). Three patients had progression of disease postoperatively. The remainder were asymptomatic (7), improved (14) or stable (2).

CONCLUSION

In a dedicated unit with neurological and intensive care support, VATS thymectomy is a safe, effective method of obtaining remission or improvement in myasthenia gravis (MG). While achieving the same surgical goal, this approach offers advantages of improved cosmesis, shorter recovery time and minimal chest wall disruption over the gold standard of sternotomy. Better patient acceptance of this minimally invasive technique may result in wider application of the benefits of thymectomy in MG.

Communication with deaf and hard-of-hearing people: a guide for medical education

Some physicians may be insufficiently prepared to work with the many patients who have hearing loss. People with hearing loss constitute approximately 9% of the U.S. population, and the prevalence is increasing. Patients with hearing loss and their physicians report communication difficulties; physicians also report feeling less comfortable with these patients. Although communication with patients plays a major role in determining diagnoses and management, little attention is given to teaching medical students and residents the skills necessary to facilitate communication when hearing loss is involved. The need for these skills will increase with the expected rise in the number of such patients. The author presents the rationale for including information about hearing loss in curricula on patient-doctor communication, and suggests curricular content, including background regarding hearing loss and techniques that can enhance the physician's ability to listen to (that is, "hear") and learn about the stories of these patients.

Generalized epilepsy with febrile seizures plus: mutation of the sodium channel subunit SCN1B

Generalized epilepsy with febrile seizures plus (GEFS(+)) is an important childhood genetic epilepsy syndrome with heterogeneous phenotypes, including febrile seizures (FS) and generalized epilepsies of variable severity. Forty unrelated GEFS(+) and FS patients were screened for mutations in the sodium channel beta-subunits SCN1B and SCN2B, and the second GEFS(+) family with an SCN1B mutation is described here. The family had 19 affected individuals: 16 with typical GEFS(+) phenotypes and three with other epilepsy phenotypes. Site-specific mutation within SCN1B remains a rare cause of GEFS(+), and the authors found no evidence to implicate SCN2B in this syndrome.

Cross-cultural communication with patients who use American Sign Language

BACKGROUND

Although American Sign Language (ASL) is the third most commonly used primary language in the United States, physicians are often not adequately prepared for the challenges of conducting an interview with a deafpatient who signs.

METHODS

A search of MEDLINE and PsychINFO databases for research on physician-patient communication and deaf people who use ASL was performed. Expert opinion helped guide discussion and recommendations.

RESULTS

Few articles examined physician-patient communication involving ASL. Deaf people and their physicians report difficulties with physician-patient communication. Deaf people also report fear that their health care is substandard because of these difficulties.

CONCLUSIONS

Preparing residents and medical students for working with patients and families who communicate in ASL presents many opportunities for teaching about physician-patient communication. ASL is quite different from English, and users of ASL often have sociocultural norms that differ from those of the majority culture. In addition to learning how to communicate with patients and families across languages and cultures, students and residents can learn how to collaborate with interpreters and how low literacy impacts physician-patient communication. Opportunities to teach about family dynamics, disability issues, and nonverbal communication also present themselves when working with families with Deaf members. Physician-patient communication involving ASL is an area that is ready for further research.