Expression of the neonatal Fc receptor, FcRn, on human intestinal epithelial cells.

Maternal IgG is transferred to the suckling mouse and rat through a major histocompatibility complex (MHC) class I-related Fc receptor (FcRn) on the brush border of the proximal small intestine. We have previously described a site on the epithelial surface of the human fetal intestine with IgG binding characteristics similar to FcRn. We report here the identification by reverse transcriptase polymerase chain reaction amplification and sequencing of the human orthologue of rat and mouse FcRn in tissue obtained from human fetal and adult intestine.

An evaluation of colchicine as an alternative to inhaled corticosteriods in moderate asthma. National Heart, Lung, and Blood Institute's Asthma Clinical Research Network.

Colchicine demonstrates an array of anti-inflammatory properties of potential relevance to asthma. However, the efficacy of colchicine as an alternative to inhaled corticosteroid therapy for asthma is unknown. Five centers participated in a controlled trial testing the hypothesis that in patients with moderate asthma needing inhaled corticosteroids for control, colchicine provides therapeutic benefit as measured by maintenance of control when inhaled steroids are discontinued.

Antileukotrienes in the treatment of asthma.

Purpose: To review the activity in clinical models, the efficacy, and the safety of antileukotrienes as a new class of antiasthma treatment.

Data Sources: English-language trials identified from the archival literature, including the MEDLINE database, through 1996; bibliographic references; and textbooks.

Study Selection: Reports from placebo-controlled, double-blind, randomized trials were selected.

Case characteristics and trends in pediatric tuberculosis, Maryland, 1986-1993.

Objective: To identify case characteristics and trends in the incidence of pediatric tuberculosis (TB) in Maryland during the national resurgence of the disease.

Methods: The authors conducted a retrospective review of the 248 cases of TB in children ages 19 and younger reported to the state registry between 1986 and 1993.

Results: The incidence of pediatric TB in Maryland, while showing a downward trend between 1986 and 1993, was characterized by a bimodal pattern, with one peak in children younger than age 5 and another peak in adolescents.

Naturally occurring mutations in the human 5-lipoxygenase gene promoter that modify transcription factor binding and reporter gene transcription.

Five lipoxygenase (5-LO) is the first committed enzyme in the metabolic pathway leading to the synthesis of the leukotrienes. We examined genomic DNA isolated from 25 normal subjects and 31 patients with asthma (6 of whom had aspirin-sensitive asthma) for mutations in the known transcription factor binding regions and the protein encoding region of the 5-LO gene. A family of mutations in the G + C-rich transcription factor binding region was identified consisting of the deletion of one, deletion of two, or addition of one zinc finger (Sp1/Egr-1) binding sites in the region 176 to 147 bp upstream from the ATG translation start site where there are normally 5 Sp1 binding motifs in tandem.

Influence of closed head injury on isoflurane MAC in the rat.

We designed the present study to determine whether the minimum alveolar concentration (MAC) for isoflurane is decreased after closed head trauma (CHT) in rats and, if so, whether the decrease of MAC is related to the severity of neurological impairment following CHT. Isoflurane MAC was determined in 36 Sprague-Dawley rats. Then, at time = 0 h, animals were grouped.

Increased clearance of IgG in mice that lack beta 2-microglobulin: possible protective role of FcRn.

The mechanisms that regulate immunoglobulin G (IgG) catabolism are little understood. We have previously found unusually low IgG concentrations in sera of mice homozygous for a targeted disruption of the beta 2-microglobulin gene. We therefore investigated whether this might result, at least in part, from increased clearance of IgG from the systemic circulation in mice lacking beta 2-microglobulin.

Diagnostic yield of bronchoalveolar lavage and bronchoscopic lung biopsy for detection of Pneumocystis carinii.

Objective: To assess the need to perform a bronchoscopic lung biopsy (BLB) in addition to bronchoalveolar lavage (BAL) to obtain a definitive diagnosis of Pneumocystis carinii pneumonia.

Design: We retrospectively reviewed the results of concurrently collected paired BAL and BLB specimens to determine the diagnostic yield of both methods for the detection of P. carinii organisms.

Comparison of regularly scheduled with as-needed use of albuterol in mild asthma. Asthma Clinical Research Network.

Background: Inhaled beta-agonists are the most commonly used treatment for asthma, but data suggest that regularly scheduled use of these agents may have deleterious effect on the control of asthma. We compared the effects of regularly scheduled use of inhaled albuterol with those of albuterol used only as needed in patients with mild chronic, stable asthma.

Methods: In a multicenter, double-blind study, we randomly assigned 255 patients with mild asthma to inhale albuterol either on a regular schedule (126 patients) or only as needed (129 patients).

The public health impact of Lyme disease in Maryland.

The purpose of this study was to estimate the health burden imposed by Lyme disease (LD) in Maryland during 1992 and 1993. A cross-sectional 1-in-15 survey of physicians (total, 1200) in Maryland was conducted to estimate the incidence of diagnosed LD, presumptive cases of LD, patients with tick bites, and diagnostic tests ordered for LD. Results show that LD is underreported by 10- to 12-fold in Maryland, that 80% of cases are managed by primary care physicians, and that there is discordance between the actual clinical treatment of patients and the recommended approach.

Effect of treatment with zileuton, a 5-lipoxygenase inhibitor, in patients with asthma. A randomized controlled trial. Zileuton Clinical Trial Group.

Objective: To study the effect of 3 months of treatment with zileuton, an inhibitor of the enzymatic pathway (5-lipoxygenase) leading to leukotriene formation, on disease control in patients with mild to moderate asthma.

Design: Randomized, double-blind, parallel-group study in 401 patients. A 10-day placebo lead-in was followed by a double-blind treatment period of 13 weeks.

Identification of childhood vaccine providers in Maryland.

The purpose of the study was to compare the utility of an American Medical Association (AMA)-derived list and a Maryland State Department of Health and Mental Hygiene (state)-derived list of potential childhood vaccine providers (CVPs) in identifying true childhood vaccine providers for the Vaccines for Children (VFC) program in Maryland. A telephone survey of a sample of physicians from the two lists was used to determine their status as providers of routine vaccinations to children. Results showed a significant difference between the two lists.

Lyme disease surveillance in Maryland, 1992.

The incidence of Lyme disease (LD) reported to the Maryland Department of Health and Mental Hygiene during 1992 was 6.5/100,000 population, ranging from 29.3 cases/100,000 on the Eastern Shore (74.

Congenital syphilis in Maryland, 1989-1991: the effect of changing the case definition and opportunities for prevention.

Background: The reported incidence of congenital syphilis in the United States rose dramatically during the 1980s. Although lack of prenatal care has been associated with congenital syphilis, little has been published regarding missed opportunities for prenatal intervention.

Goal Of This Study: To determine whether congenital syphilis increases in Maryland between 1989 and 1991 resulted from a true increase in congenital syphilis incidence or a change in the surveillance case definition, and to describe missed opportunities for prenatal intervention.

Diurnal variation of urinary leukotriene E4 and histamine excretion rates in normal subjects and patients with mild-to-moderate asthma.

Background: Leukotriene E4 (LTE4) and histamine excreted into the urine reflect the in vivo synthesis and release of cysteinyl leukotrienes and histamine, respectively. We examined the diurnal variation of the excretion rate of these mediators over 4 consecutive days in normal subjects (n = 5) and patients with stable mild-to-moderate asthma (n = 8).

Methods: Sixteen consecutive 6-hour urine samples were collected over 4 days.

Effect of chronic 5-lipoxygenase inhibition on airway hyperresponsiveness in asthmatic subjects.

The leukotrienes are known bronchoactive agonists with potential proinflammatory effects that may be involved in mediating airway hyperresponsiveness. We investigated the effects of zileuton, an inhibitor of 5-lipoxygenase (5-LO), on airway responsiveness to cold, dry air in patients with moderate asthma. A group of 10 asthmatic patients underwent cold, dry air hyperventilation challenge; challenges were performed before drug treatment and 1 to 10 d after the completion of treatment with study drugs.

Environmental risk factors for Lyme disease identified with geographic information systems.

Objectives: A geographic information system was used to identify and locate residential environmental risk factors for Lyme disease.

Methods: Data were obtained for 53 environmental variables at the residences of Lyme disease case patients in Baltimore County from 1989 through 1990 and compared with data for randomly selected addresses. A risk model was generated combining the geographic information system with logistic regression analysis.

Requirement for a beta 2-microglobulin-associated Fc receptor for acquisition of maternal IgG by fetal and neonatal mice.

There is considerable evidence to suggest that an FcR similar in structure to class I MHC Ags, neonatal Fc receptor (FcRn), transports IgG across the intestinal epithelium of suckling mice. However, this has not previously been shown definitively, nor has it been shown whether FcRn is the only, or even the major, IgG transporter in the neonatal mouse gut. We report here that neonatal mice homozygous for a targeted disruption of the beta 2microglobulin (beta 2m) gene, which encodes one subunit of FcRn, had reduced FcRn alpha-chain at the lumenal plasma membrane of intestinal cells.

Treatment of chronic stable asthma with drugs active on the 5-lipoxygenase pathway.

It is now established that 5-lipoxygenase products are synthesized and released in the airway during asthmatic reactions. The importance of these products in the asthmatic response has been established through study of the effects of 5-lipoxygenase inhibitors and leukotriene D4 receptor antagonists in patients with chronic stable asthma. In this study we review the data demonstrating that chronic administration of zileuton, an inhibitor of 5-lipoxygenase, is associated with improved airway function, decreased asthma symptoms and decreased need for asthma medication use in patients with mild to moderate asthma.

The influence of age, diagnosis, and gender on proper use of metered-dose inhalers.

Metered dose inhalers (MDIs) are widely used in clinical practice for administering pharmaceuticals targeted to the lung. It is well known that the inhalation technique used with MDIs can substantially influence the clinical response to inhaled medications. To determine the acceptability of MDI maneuvers, we studied 59 subjects (26 females and 33 males; age, 20 to 81 yr; mean age, 38 yr) to determine whether the MDI technique used by these individuals complied with published recommendations for acceptable inhalation technique.

Antibiotic therapy for Lyme disease in Maryland.

The recommended treatment of Lyme disease is evolving and important questions remain unanswered, such as (a) Are inexpensive oral regimens effective in curing acute illness and preventing arthritic, neurologic, and cardiac manifestations or are much more costly, and potentially toxic, intravenous antibiotics required? (b) Are relatively short 2- to 3-week courses of antibiotics sufficient or are prolonged regimens of a month, or more, better? This study reviews antibiotic therapy prescribed by Maryland physicians for the 283 cases reported in 1991 that meet the Centers for Disease Control and Prevention's case definition for Lyme disease. The purpose of the review was to obtain baseline information on the antibiotics being used by physicians in practice to treat patients that they believe have Lyme disease. The most frequently prescribed antibiotics for either the 60 percent of patients presenting with erythema migrans or the 40 percent with arthritic, neurologic, or cardiac manifestations were oral doxycycline (47 percent), tetracycline (11 percent), and amoxicillin (13 percent).

Influence of the polyamine, spermidine, on intestinal maturation and dietary antigen uptake in the neonatal rat.

Polyamines appear to have an important role in postnatal growth of the rat intestine. In the present study, we examined the effect of spermidine on the maturation of the intestine and on its ability to exclude macromolecules. Two litters of Sprague-Dawley rat pups were assigned to one of four experimental groups.