Identification of a potent, selective, and orally active leukotriene a4 hydrolase inhibitor with anti-inflammatory activity

LTA 4H is a ubiquitously distributed 69 kDa zinc-containing cytosolic enzyme with both hydrolase and aminopeptidase activity. As a hydrolase, LTA 4H stereospecifically catalyzes the transformation of the unstable epoxide LTA 4 to the diol LTB 4, a potent chemoattractant and activator of neutrophils and a chemoattractant of eosinophils, macrophages, mast cells, and T cells. Inhibiting the formation of LTB 4 is expected to be beneficial in the treatment of inflammatory diseases such as inflammatory bowel disease (IBD), asthma, and atherosclerosis. We developed a pharmacophore model using a known inhibitor manually docked into the active site of LTA 4H to identify a subset of compounds for screening. From this work we identified a series of benzoxazole, benzthiazole, and benzimidazole inhibitors. SAR studies resulted in the identification of several potent inhibitors with an appropriate cross-reactivity profile and excellent PK/PD properties. Our efforts focused on further profiling JNJ 27265732, which showed encouraging efficacy in a disease model relevant to IBD.

Anti-inflammatory activity of a potent, selective leukotriene A4 hydrolase inhibitor in comparison with the 5-lipoxygenase inhibitor zileuton

Leukotriene A(4) hydrolase (LTA(4)H) catalyzes production of the proinflammatory lipid mediator, leukotriene (LT) B(4), which is implicated in a number of inflammatory diseases. We have identified a potent and selective inhibitor of both the epoxide hydrolase and aminopeptidase activities of recombinant human LTA(4)H (IC(50), approximately 10 nM). In a murine model of arachidonic acid-induced ear inflammation, the LTA(4)H inhibitor, JNJ-26993135 (1-[4-(benzothiazol-2-yloxy)-benzyl]-piperidine-4-carboxylic acid), dose-dependently inhibited ex vivo LTB(4) production in blood, in parallel with dose-dependent inhibition of neutrophil influx (ED(50), 1-3 mg/kg) and ear edema. In murine whole blood and in zymosan-induced peritonitis, JNJ-26993135 selectively inhibited LTB(4) production, without affecting cysteinyl leukotriene production, while maintaining or increasing production of the anti-inflammatory mediator, lipoxin (LX) A(4). The 5-lipoxygenase (5-LO) inhibitor zileuton showed inhibition of LTB(4), LTC(4), and LXA(4) production. Although zileuton inhibited LTB(4) production in the peritonitis model more effectively than the LTA(4)H inhibitor, the influx of neutrophils into the peritoneum after 1 and 2 h was significantly higher in zileuton- versus JNJ-26993135-treated animals. This difference may have been mediated by the increased LXA(4) levels in the presence of the LTA(4)H inhibitor. The selective inhibition of LTB(4) production by JNJ-26993135, while increasing levels of the anti-inflammatory mediator, LXA(4), may translate to superior therapeutic efficacy versus 5-LO or 5-LO-activating protein inhibitors in LTB(4)-mediated inflammatory diseases.

Histamine H4 receptor antagonists are superior to traditional antihistamines in the attenuation of experimental pruritus

BACKGROUND

Histamine is a potent mediator of itch in humans, yet histamine H(1) receptor antagonists have been shown to be of limited use in the treatment of certain chronic pruritic diseases. The histamine H(4) receptor is a recently described histamine receptor, expressed on hematopoietic cells, linked to the pathology of allergy and asthma.

OBJECTIVE

The contribution of the novel histamine H(4) receptor to histaminergic and allergic pruritus was investigated.

RESULTS

Histamine and a selective histamine H(4) receptor agonist caused scratching responses in mice, which were almost completely attenuated in histamine H(4) receptor knockout mice or by pretreatment with the selective histamine H(4) receptor antagonist, JNJ 7777120. Pruritus induced by allergic mechanisms was also potently inhibited with histamine H(4) receptor antagonist treatment or in histamine H(4) receptor knockout mice. In all cases, the inhibitory effect of histamine H(4) receptor antagonist was greater than those observed with histamine H(1) receptor antagonists. The histamine H(4) receptor-mediated pruritus was shown to be independent of mast cells or other hematopoietic cells and may result from actions on peripheral neurons.

CONCLUSION

These results demonstrate that the histamine H(4) receptor is involved in pruritic responses in mice to a greater extent than the histamine H(1) receptor.

CLINICAL IMPLICATIONS

Histamine H(4) receptor antagonists may have therapeutic utility for treating chronic pruritic diseases in humans where histamine H(1) receptor antagonists are not effective.

The histamine H4 receptor mediates allergic airway inflammation by regulating the activation of CD4+ T cells

Histamine is an important inflammatory mediator that is released in airways during an asthmatic response. However, current antihistamine drugs are not effective in controlling the disease. The discovery of the histamine H4 receptor (H4R) prompted us to reinvestigate the role of histamine in pulmonary allergic responses. H4R-deficient mice and mice treated with H4R antagonists exhibited decreased allergic lung inflammation, with decreases in infiltrating lung eosinophils and lymphocytes and decreases in Th2 responses. Ex vivo restimulation of T cells showed decreases in IL-4, IL-5, IL-13, IL-6, and IL-17 levels, suggesting that T cell functions were disrupted. In vitro studies indicated that blockade of the H4R on dendritic cells leads to decreases in cytokine and chemokine production and limits their ability to induce Th2 responses in T cells. This work suggests that the H4R can modulate allergic responses via its influence on T cell activation. The study expands the known influences of histamine on the immune system and highlights the therapeutic potential of H4R antagonists in allergic conditions.

A potent and selective histamine H4 receptor antagonist with anti-inflammatory properties

Histamine mediates its physiological function through binding to four known histamine receptors. Here, we describe the first selective antagonist of the histamine H4 receptor, the newest member of the histamine receptor family, and provide evidence that such antagonists have anti-inflammatory activity in vivo. 1-[(5-chloro-1H-indol-2-yl)carbonyl]-4-methylpiperazine (JNJ 7777120) has a K(i) of 4.5 nM versus the human receptor and a pA(2) of 8.1. It is equipotent against the human, mouse, and rat receptors. It exhibits at least 1000-fold selectivity over H1, H2, or H3 receptors and has no cross-reactivity against 50 other targets. This compound has an oral bioavailability of approximately 30% in rats and 100% in dogs, with a half-life of approximately 3 h in both species. JNJ 7777120 blocks histamine-induced chemotaxis and calcium influx in mouse bone marrow-derived mast cells. In addition, it can block the histamine-induced migration of tracheal mast cells from the connective tissue toward the epithelium in mice. JNJ 7777120 significantly blocks neutrophil infiltration in a mouse zymosan-induced peritonitis model. This model is reported to be mast cell-dependent, which suggests that the compound effect may be mediated by mast cells. These results indicate that the histamine H4 receptor plays a role in the inflammatory process. Selective H4 receptor antagonists like JNJ 7777120 may have the potential to be useful in treating inflammation in humans.

Identification of a Potent and Selective Noncovalent Cathepsin S Inhibitor

Cathepsin S is considered crucial for normal presentation of major histocompatibility complex (MHC) class II-restricted antigens by antigen presenting cells to CD4+ T cells. It is a key enzyme for the degradation of the class II-associated invariant chain, a process that is required for effective antigen loading of class II molecules. Here, we report a selective, orally available, high-affinity cathepsin S inhibitor, 1-[3-[4-(6-Chloro-2,3-dihydro-3-methyl-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]propyl]-4,5,6,7-tetrahydro-5-(methylsulfonyl)-3-[4-(trifluoromethyl)phenyl]-1H-pyrazolo[4,3-c]pyridine. (JNJ 10329670), that represents a novel class of immunosuppressive compounds. JNJ 10329670 is a highly potent (Ki of approximately 30 nM), nonpeptidic, noncovalent inhibitor of human cathepsin S, but it is much less active against the mouse, dog, monkey, and bovine enzymes. The compound is inactive against other proteases, including the closely related cathepsins L, F, and K. This selectivity makes JNJ 10329670 an excellent tool for exploring the role of cathepsin S in human systems. Treatment of human B cell lines and primary human dendritic cells with JNJ 10329670 resulted in the accumulation of the p10 fragment of the invariant chain (IC50 of approximately 1 microM). In contrast, inhibition of invariant chain proteolysis was much less effective in a human monocytic cell line, suggesting that other enzymes may degrade the invariant chain in this cell type. JNJ 10329670 was shown to block the proteolysis of the invariant chain in vivo by using immunocompromised mice injected with human peripheral blood mononuclear cells (PBMCs). Furthermore, this inhibitor blocks the presentation of tetanus toxoid and giant ragweed by human PBMCs. The properties of JNJ 10329670 make it a candidate for immunosuppressive therapy of allergies and autoimmune diseases.

Implications of differential impacts of care-giving for future research on Alzheimer care

As the primary caregivers for the millions afflicted with Alzheimer's disease, family members have been the focus of research for the past two decades. Differences in care patterns and deleterious effects of care provision have been clearly established. However, similar demands and hardships associated with care-giving result in different consequences for different families. A greater understanding of the care-giving context and its determinants will enhance knowledge of the differential impacts of care-giving. The most critical determinant of care-giving context is the role relationship between the caregiver and the care recipient. Future research must address role relationship as the primary determinant of what care is provided by whom, and in what manner. This will enhance the understanding of specific caregiver outcomes and lead to optimal targeting of interventions. Future research must also focus on the interface between the family and other social institutions. Evidence calls into question the equity, quality, and capacity of the current system of care, which assumes that family care is best. It will be important for future studies to explore alternate options for long-term care policy. Families and patients will also benefit from studies that assess strategies to ensure an adequate labor pool of qualified formal caregivers.

The influence of gender on incidence and outcome of patients with bladder cancer in Harlem

Although African Americans have a lower incidence of bladder cancer, overall survival is worse compared with American whites. This phenomenon has been attributed to the higher incidence of advanced disease at diagnosis and poor follow-up. Fifty-nine cases of bladder cancer were identified through the Tumor Registry at Harlem Hospital and reviewed retrospectively. Complete data were obtained for 42 patients. The primary independent variables of interest were primary care utilization, comorbid conditions, social variables, and gender. The outcome variables of interest were stage of disease at presentation and death. The median age at diagnosis in this group was 73 years compared with 68 for bladder cancer patients in the United States. There was no statistically significant correlation between primary care utilization or severity of comorbidities, and clinical stage at presentation. Similarly, these variables did not influence the occurrence of death as an outcome. For women, the mean age at diagnosis was 74.2 years compared with 67.3 in men (P = .112). The ratio of male-to-female cases in this group was 1.3 to 1 compared with 2.7 to 1 for the general US population. Women had lower odds of being diagnosed with superficial disease (OR = 0.24, 95% CI, 0.06-0.94) and a higher incidence of a cancer-specific death (OR = 2.7, 95% CI). The poor outcome and high incidence of bladder cancer cases among women in Harlem is intriguing. Overall, primary care utilization, comorbidities, and other social factors did not seem to influence stage or death as an outcome. The significantly elevated prevalence of smoking among women in this community, increased age at diagnosis, and possible environmental influences may play a role.

Screening for postpartum depression. An antepartum questionnaire

OBJECTIVE

To develop and evaluate a questionnaire used antepartum to screen for postpartum depression.

STUDY DESIGN

Demographic and clinical data, based on previously identified variables, were obtained from 106 second-trimester gravidas (sample I) by interview, self-administered questionnaire and medical record review. The Beck Depression Inventory (BDI) was administered at 1, 6 and 12 weeks postpartum (PP). Statistical analysis, including stepwise linear regression with maximum r-squared improvement, identified a subset of the 24 most predictive variables. This antepartum questionnaire (APQ) was validated retrospectively in the original sample and prospectively in a second group of 99 women (sample II).

RESULTS

In both sample populations the APQ had acceptable sensitivity (80-82%) and specificity (78-82%). The incidence of postpartum depressive symptoms (PPDS) rose from 10% to 17% by six weeks without an appreciable decline at 12 weeks (15%). The percentage of women showing more than mild depressive symptoms increased with PP time from 30% at 1 week to 47% at 12.

CONCLUSION

The APQ is now available for screening and evaluating early therapeutic intervention in PPDS.

High density sickle cell erythrocyte core membrane skeletons demonstrate slow temperature dependent dissociation

We have previously demonstrated that slow dissociation of HDSS membrane skeletons in high ionic strength Triton X-100 buffer was related to a posttranslational modification in beta-actin, in which a disulfide bridge was formed between cysteine 284 and cysteine 373[Shartava et al: J Cell Bio 128:805, 1995]. These previous dissociation assays were limited to two homozygous (SS) sickle cell patients and a single temperature (37 degrees C). In the current work, we have expanded the SS subjects to 9 and have carried out dissociation assays at 0, 24, 30, 34, and 37 degrees C. At 0 degrees C there was limited dissociation of spectrin and actin from normal(AA), low density sickle cell(LDSS), and high density sickle cell (HDSS) core skeleton up to 24 hr. The first order rate constants for dissociation of spectrin, at 0 degrees C, was 0.030-0.035 x 10-4 sec-1 for AA,LDSS, and HDSS core skeletons. However at 24, 30, 34, and 37 degrees C the rate of dissociation of spectrin from HDSS core skeletons was significantly slower than the rate of dissociation from AA core skeletons. Having determined the first order rate constants for spectrin dissociation at these specified temperatures, we then asked whether dithiothreitol (DTT) would hasten the dissociation of core skeletons. The presence of DTT caused the rate of dissociation of the HDSS membrane skeleton to become statistically indistinguishable from the rate of dissociation of AA membrane skeletons. This is consistent with the suggestion that reversible thiol oxidation is responsible for the slow dissociation of the HDSS membrane skeleton.

Crafting effective tobacco counteradvertisements: lessons from a failed campaign directed at teenagers

Focus group research conducted by the Centers for Disease Control and Prevention's Office on Smoking and Health suggested that the desire of teenagers to gain control over their lives would make them responsive to a counteradvertising strategy aimed at exposing the predatory marketing techniques of the tobacco industry. On the basis of this strategy, the office developed draft print advertisements and a rough TV commercial featuring such theme lines as "You get an image. They get an addict." In those ads, "they" referred to cigarette companies. Subsequent testing of the campaign materials, however, indicated that the subtle, sophisticated execution of this concept of manipulation by the industry did not communicate clearly and effectively to an audience of young teens. In fact, 38 percent of those who viewed the rough TV spot believed that the main message promoted smoking. These negative test findings underscore the critical need for ongoing audience research throughout the creative process to ensure that campaign planners stay "in tune" with their consumers.

Unexpected, difficult laryngoscopy: a prospective survey in routine general surgery

A prospective study of unexpected, difficult laryngoscopy was carried out. During a 7-month period, all general surgery patients in whom the trachea was intubated were assessed; only those with obvious neck pathology were excluded. Ease or difficulty of laryngoscopy was graded by a standard method. There were no grade 4 cases and no failed intubations in a total of 1387 cases. There were significant differences in the results recorded by different individuals; this did not correlate with seniority or with the type of surgery. Four factors have been identified which help to explain these discrepancies. These findings are analysed in relation to the training of junior staff, with particular reference to obstetric anaesthesia.

Postpartum depressive disorders: changing trends

For centuries, there has been speculation regarding the etiology of postpartum depression. An improved diagnostic classification has emerged, however, as the universality of the syndrome has been recognized and the role of hormonal, genetic, and obstetric variables considered. In addition, different cultures have different perceptions of the needs of the new mother. The emphasis in investigative work now appears to be in the psychosocial and psychodynamic areas. Our recent research focused on identification of risk factors early in pregnancy, including a history of depression, separation from one or both parents in childhood or adolescence, poor parental emotional support in childhood and adulthood, poor relationship with husband or partner, economic problems, and dissatisfaction with amount of education. We suggest that physicians, nurses, and mental health professionals be aware of the emotional status of their patients, familiarize themselves with the risk factors, and initiate a program of careful postpartum follow-up. These measures will help to improve recognition and management of the woman at risk for postpartum depression.

Epidural haematoma requiring surgical decompression following repeated cervical epidural steroid injections for chronic pain

We report a case of epidural haematoma following a steroid injection into the cervical epidural space. The complication occurred on the seventh such injection over a 2 year period for chronic spinal pain. Surgical decompression over the seventh cervical and the upper 3 thoracic vertebrae was required to alleviate the symptoms of paralysis and anaesthesia. The patient subsequently required skin grafting to the surgical site and two trans-urethral resections of the prostate gland during his 6 week hospital admission. He made a full recovery.

The oesophageal detector device. A prospective trial on 100 patients

Misplacement of a tracheal tube in the oesophagus remains a significant cause of mortality and morbidity in anaesthesia, despite decades of effort aimed at prevention, or perhaps more importantly, detection, of such an event. We have evaluated a cheap, simple and quick device which relies mainly on the reflation or otherwise of an Ellick's evacuator applied to the supposed 'tracheal' tube. Identical tracheal tubes were passed into the trachea and oesophagus of 100 patients; the left and right position in the mouth was chosen at random. The test was conducted by a second anaesthetist, not present at intubation, and unaware of which tube was in the trachea. There were no false positive results and the correct deduction of which was the tracheal tube was reached in 100 tests using this device. Its use is recommended for widespread evaluation as a valuable adjunct to existing methods of detecting misplacement.

Computerised cardiological case notes

Optical Mark Reader forms have been used by the Cardiac Department at St Thomas's Hospital for six years to store clinical and haemodynamic data by computer. Forms are completed by clinical staff in outpatients and also for those patients undergoing cardiac catheterisation. Three documents are used to record the symptoms and signs at the clinical consultation, the results of relevant investigations, and the important findings at cardiac catheterisation. These documents are fed into a computer and data from them, together with a limited quantity of types information, are used to produce full clinical reports for our colleagues and the case notes. There reports have saved much secretarial and medical time. A variety of analyses is available for research and management purposes.

Self-administration of D-Ala2-Met-enkephalinamide at hypothalamic self-stimulation sites

The relationship between the action of enkephalin and the reinforcing action of electrical stimulation in the posterior lateral hypothalamus of the rat was studied with the self-administration approach. Adult male albino rats implanted with a combination cannula and stimulation electrode in hypothalamus were pretested for the reinforcing effects of electrical stimulation. Only subjects that self-stimulated at moderate to high rates were given self-administration tests. The chamber for the self-administration tests was fitted with one lever at each end of a rectangular plexiglass box. In a session, one lever was 'active', the other not. The active lever, if depressed, yielded 20 nl of CSF (artificial cerebrospinal fluid), or CSF in which one of the test substances was dissolved. Each subject was tested repeatedly for the reinforcing effects first of a control solution (CSF), then of D-Ala2-Met-enkephalin (DALA), a long-acting synthetic analogue of enkephalin, then of morphine, and then of opioids mixed with naltrexone or naloxone. Following these tests, the subjects were once again given self-stimulation tests to ascertain the functional integrity of the 'reward' system after the repeated self-administration tests. The results demonstrate that when the test solution was DALA instead of CSF the subjects pressed the active lever at a higher rate than for CSF, and they exhausted the supply more rapidly than for CSF. The rate on the active lever was also significantly higher than on the inactive lever. DALA at 1 and 5 microgram/microliter concentrations proved more reinforcing than at 0.1 microgram/microliter. Naltrexone did not block the reinforcing effect of DALA, whereas naloxone blocked DALA-induced reinforcement. These data extend the report of ventricular methionine-enkephalin positive reinforcement to DALA injected directly into the lateral hypothalamus.

A computer system for clinical microbiology

The Department of Clinical Microbiology at St Thomas' Hospital has been producing bacteriological reports on a computer for more than three years and is now producing some 2300 reports per week. The system is operated entirely by laboratory staff without special training, and involves the use of optical mark reader (OMR) forms as worksheets, automatic validation and release of most reports, the use of local terminals, and scrutiny of reports by pathologists using a visual display unit. The OMR worksheet records not only the final result but also most of the tests and observations made on the samples; it is the only working document used by technicians. One specialist clinic submits its laboratory requests on an OMR form, which is subsequently used to record the results. The reports are printed and also filed in the computer to produce analyses for hospital, laboratory, and clinical management.

Auditory temporal resolution: effects of sensation level

Experienced Ss identified (2IFC) the signal complex that contained a gap. When the complexes were of the same frequency, gap detection remained constant over the durations employed (up to 300 msec). When duration of the signal was 10 msec no changes in gap threshold occurred over the range of frequency disparities between signals (up to 120 Hz at F0 = 1 kHz). However, as signal duration increased (beyond 10 msec) there was an increase in gap threshold with increased frequency disparity. The degradation in gap threshold was greater for longer-duration events. Gap threshold was shown to decrease as a function of increase in intensity of the signals.

Use, costs, and quality of medical services: impact of the New Mexico peer review system. A 1971-1975 study

To assess the effect of areawide peer review (such as that conducted by Professional Standards Review Organizations [PSROs]) on use, cost and quality of medical services, we evaluated 4 years of data on the efforts of the New Mexico Experimental Medical Care Review Organization in reviewing medical services for the Medicaid population. Utilization review had no demonstrable impact on hospital use; hospital days per 100 eligible persons rose 5.0% and 43.4% for persons enrolled all 4 years in Aid to Families with Dependent Children (AFDC) and Aid to the Permanently and Totally Disabled, respectively. Peer review produced no net dollar savings; over 4 years, the amount paid for all services per AFDC-eligible person rose 85%. Peer review improved the quality of ambulatory care through large reductions (75%) in medically unnecessary injections. If these findings are replicated elsewhere, they suggest that the goal of the PSRO program to control costs by curtailing utilization may be difficult to achieve, the quality of care goal may be pursued successfully, and the PSRO mission should be focused more on the latter.

Quality assurance today and tomorrow: forecast for the future

We review here the definition, history, and current findings of quality assessment. Difficulties with quality assessment center principally on methods problems, including using the medical record as a source of information, using process versus outcome criteria, and ignoring decision analysis methods in establishing quality criteria. One overriding issue is placing a value on health and, by extension, on quality assurance and assessment efforts; another is the degree to which improvements in the quality of care can be achieved through changes in physician practices. Several sets of recommendations address these topics. With the assumption that such recommendations could be acted on in a transition period, a hypothetical quality assurance system is described for the 1980s and beyond. This system is based on preservation of the fee-for-service system, adoption of a national health insurance plan, and minimal federal involvement in quality of care decisions at the regional level.

Effect of medical care review on the use of injections: a study of the New Mexico Experimental Medical Care Review Organization

Evaluation of peer review activities in the New Mexico Medicaid program (1971 to 1973) showed that it can affect aspects of quality, that is, the appropriateness of the use of injections as judged by medical criteria. Use of injections, nearly 50% of which were antibiotics, declined by more than 60%, from 41 to 16 per 100 ambulatory visits. Still, at the end of the study, 40% of the injections given were considered medically unnecessary. Analyses showed that [1] groups used injections more appropriately; [2] for solo physicians, being board-certified, being a doctor of medicine, and being a pediatrician were all associated with more proper use of injections; [3] 6% of the physicians gave 40% of the medically unnecessary injections, but even their behavior changed dramatically for the better as a result of the peer review system.

Signal onset and task variables in auditory evoked potentials

Two auditory evoked potential studies were run to determine the effects of stimulus rise times on amplitude of N1-P2 onset and offset potentials. Onset potentials were reduced with increased onset durations. No consistent relationship was found in N1-P2 offset potentials as a function of stimulus rise time. The effects of listening tasks and stimulus duration were also examined.

Quality of health care for the disadvantaged

Literature review points out that: (a) differentials in health status between the disadvantaged and the nondisadvantaged persist, often to a large degree; (b) differentials in the overall amount of care received are less striking now than heretofore, but standardization by level of need demonstrates measurable discrepancies in health services provided to the disadvantaged compared with the nondisadvantaged; (c) the quality of health care for the disadvantaged is not strikingly poorer than care for the nondisadvantaged, but, in view of demonstrable shortcomings in the quality of health care in general, this is not viewed as a positive statement; and (d) attempts to improve quality of care for the disadvantaged have not had the hoped-for impact. Four new avenues are suggested for possible further research; increased patient responsibility, increased consumer knowledge, financial accountability, and quality assurance activities. Because of the likelihood of only marginal changes in health status, rigorous evaluation of any experimental program is emphasized. During the last decade, many attempts have been made by private and governmental bodies to improve the health of the American people. In general, these efforts have focused on improving the health of members of disadvantaged groups and have included such diverse activities as building OEO health centers, developing maternal and infant care programs, and financing care for the elderly. During the last few years, a different movement, concerned with assuring high quality care for all people, has produced efforts such as quality assurance activities in health maintenance organizations, the Professional Standards Review Organization program, and the medical care evaluation program of the Joint Commission on the Accreditation of Hospitals. Consideration of these two issues, i.e., improving the health of disadvantaged groups and improving the quality of care for all people, has led to two policy-relevant questions: "Can the health of disadvantaged groups be substantially improved by assuring that a high level quality of care is delivered to them?" and "Can the quality of care delivered to disadvantaged groups be improved?" The purpose of this paper is to review some available data pertinent to both these issues and to suggest some ideas for future research.

A computer program for the analysis of parallel-line bioassays of clotting factors

An interactive computer program for the analysis of clotting factor assays is described. The program provides potency estimates against a standard, and will compare the observed and expected responses of a treated patient. Tests for validity of curve fitting are provided, with a number of optional transforms. If asked, the program will provide the user with a list of valid commands at any given step, and will identify certain errors in input.

Migration of foreign physicians to the United States: the perspective of health manpower planning

Effective health manpower planning in the United States, on both the national and state levels, is complicated by the interstate and international movement of health professionals. Migration of foreign medical graduates into the United States, which is one major aspect of this movement, is an extremely complex problem, involving both quantitative and qualitative issues. Background information and available data on immigration, demographic and professional characteristics, and performance of foreign medical graduates are summarized in the paper. Past recommendations and recent trends are discussed. The need for implementation of a coherent set of national policy guidelines is highlighted.