The inception, achievements, and implications of the China GAVI Alliance Project on Hepatitis B Immunization

The China GAVI Hepatitis B Immunization Project was initiated in 2002 with the signing of a Memorandum of Understanding between GAVI and the Government of China. The Project was one of the three (China, India, and Indonesia) GAVI-initiated special projects done to support countries too large to receive full GAVI support for hepatitis B vaccine and safe injections. The Project in China was designed by the Chinese Government and partners to deliver free hepatitis B vaccine and safe injections to all newborns in the 12 Western Provinces and Poverty Counties in 10 Provinces of Central China (1301 Counties with approximately 5.6 million births per year), eliminating the gap in immunization coverage between wealthier and poorer regions of China. The project budget (USD 76 million) was equally shared by GAVI and the Chinese Government. Initially planned for 5 years, two no cost extensions extended the project to 2011. Although China produced hepatitis B vaccine, before the project the vaccine was sold to parents who were also charged a "user fee" for the syringe and vaccine administration. Basic Expanded Program on Immunization (EPI) vaccines such as BCG, DTP, Polio, and measles vaccines were provided free to parents, although they were charged a user fee. Vaccines were sold by China CDC Offices at provincial, prefecture, county level and township hospitals, and village doctors received a substantial portion of their income from the sale of hepatitis B and other vaccines. The result of charging for hepatitis B vaccine was that coverage was relatively high in Eastern and wealthier counties in Central China (~80-90%), but was much lower (~40%) in Western China and Poverty Counties where parents could not afford the vaccine. The Project was administered by the China MOH and China CDC EPI program, and two Project Co-managers, one from the Chinese Government and the other an international assignee, were chosen. The project had an oversight Operational Advisory Group composed of the Chinese Government, WHO, UNICEF, and GAVI. The initial targets of the project as delineated in the initial MOU for the Project areas (HepB3 coverage will reach 85% at the county level, >75% of newborns at the county level will receive the first dose of hepatitis B within 24h of birth, and all immunization injections will be with auto disable [AD] syringes) were substantially exceeded. The differential in vaccine coverage between wealthier and poorer parts of China was eliminated contributing to a great improvement in equity. With additional contributions of the Chinese Government the Project was accomplished substantially under budget allowing for additional catch up immunization of children under 15 years of age. More than 5 million health workers were trained in how to deliver hepatitis B vaccine, timely birth dose (TBD), and safe injections, and public awareness of hepatitis B and its prevention rose significantly. TBD coverage was expedited by concurrent efforts to have women deliver in township clinics and district hospitals instead of at home. The effective management of the Project, with a Project office sitting within the China EPI and an Operational Advisory Group for oversight, could serve as a model for other GAVI projects worldwide. Most importantly, the carrier rate in Chinese children less than 5 years of age has fallen to 1%, from a level of 10% before the inception of the Project. Liver cancer, one of the major cancer killers in China (250,000-300,000 annual estimated deaths), will dramatically decline as immunized cohorts of Chinese children age. While hepatitis C and non-alcoholic liver disease also exist in China and can lead to liver cancer and cirrhosis, the majority of liver disease in China is hepatitis B related and therefore preventable. The authors believe that China's success in preventing hepatitis B is one of the greatest public health achievements of the 21st century. Work remains to be done in several key areas. There are still pockets of home births in rural provinces where a TBD is difficult to deliver, and China is strengthening its policy of screening pregnant women for HBsAg and delivering HBIG plus vaccine to newborns of HBV carrier mothers. Approximately 10% of the adult population of China remain chronic carriers of hepatitis B virus and cannot be helped by the vaccine, so prevention of liver cancer and cirrhosis in those groups remains a future challenge for China.

A phase II study of axitinib (AG-013736 [AG]) in patients (pts) with advanced thyroid cancers

6008

Background: Elevated VEGF-A and VEGF-C have been reported in thyroid tumor tissue compared with normal thyroid. AG is a potent, small molecule inhibitor of VEGF receptors 1, 2 and 3. The efficacy and safety of AG therapy in pts with advanced thyroid cancers was examined in this single-arm, multi-center study. Methods: 60 pts with metastatic or unresectable locally-advanced thyroid cancer refractory to, or not suitable candidates for, 131iodine (131I) treatment, with measurable disease received AG at a starting dose of 5 mg orally BID. The primary endpoint was response rate (RR) by RECIST criteria. A Simon 2-stage minimax design was used (a=0.1; β=0.1; null RR=5%; alternative RR=20%). Samples were collected pretreatment and q8wks to explore relationships between clinical response and plasma soluble proteins. Results: Median age was 59 yrs (26–84), 35 (58%) were male. Histological subtypes included papillary: 29 pts (48%); follicular: 15 pts (25%)-11 (18%) with Hurthle cell variant; medullary: 12 pts (20%); anaplastic: 2 pts (3%), and other/unknown: 2 pts (3%). 53 pts (88%) had prior surgery, 42 (70%) had prior 131I treatment, 27 (45%) had prior external beam radiation, and 9 (15%) had prior chemotherapy. Partial response (PR) by investigator report was achieved in 13 pts (22% CI: 12.1, 34.2), with 31- 68% maximum tumor regression and duration of response (DOR) of 1–16 months. 30 pts (50%) have stable disease with a duration range of 4–13 months and 13–67% maximum tumor regression in 28 pts. Response assessments are ongoing. The treatment duration range is 6–670 days with 38 pts currently on study. Median PFS has not been reached with a median follow up of 273 days. The most common treatment-related adverse events were fatigue (37%), proteinuria (27%), stomatitis/mucositis (25%), diarrhea (22%), hypertension (20%) and nausea (18%). AG therapy consistently decreased soluble VEGFR2 and VEGFR3, and increased VEGF in the blood, demonstrating pharmacodynamic activity against targeted VEGF receptors. Conclusions: AG has substantial anti-tumor activity in advanced thyroid cancer with demonstrated pharmacodynamic activity. A global pivotal trial testing AG in doxorubicin refractory thyroid cancer is ongoing.

[Table: see text]

Effects of fluorescent probe structure on the dynamics at cysteine-34 within bovine serum albumin: evidence for probe-dependent modulation of the cybotactic region

We have prepared a series of bovine serum albumins (BSA) that have been site-selectively labeled at cysteine-34 with one of four different sulfhydryl-selective boron dipyrromethene difluoride (BODIPY) fluorescent probes (BODIPY FL IA, BODIPY FL C(1) IA, BODIPY 530/550 IA, and BODIPY 493/503 MB). We determine how the choice of extrinsic probe structure dictates the recovered BSA-BODIPY dynamics under thermal (10-80 degrees C) and chemical (0-5M guanidine hydrochloride) denaturation conditions. The results of these experiments show that the global protein dynamics are sensed equally by each fluorescent probe; however, the probe itself influences the local probe dynamics within the cybotactic region that surrounds cysteine-34. Thus, it seems inappropriate to think of these extrinsic fluorescent probes as passive, nonparticipatory viewers of local protein dynamics.

Infant and adolescent hepatitis B immunization up to 1999: a global overview

This article presents a global overview of hepatitis B infant and adolescent immunization programmes. The 108 reported universal infant or adolescent immunization programmes and 87 reported national infant coverage rates fit a pattern, explained by hepatitis B endemicity, prosperity, policy emphasis, and immunization programme strength. Most East and Southeast Asian, Pacific, and Middle Eastern countries have intermediate to highly endemic hepatitis B. Most have achieved 65-100% coverage. South and Central Asia and sub-Saharan Africa have intermediate to high endemicity, with some countries having hepatitis B immunization programmes. Some Southern and Eastern European countries, with intermediate endemicity, have high coverage. Low endemic Northern European countries vaccinate higher risk groups; some have universal infant or adolescent programmes. Caribbean and Latin American countries have varying endemicity, and most started programmes. Low endemic North American countries have universal vaccination programmes. Universal immunization strategies have greatly reduced incidence and prevalence, and are cost-effective for many countries, but many have difficulties affording this vaccine. Globally, most infants are not being immunized against hepatitis B virus infection. Increasing coverage, and decreasing the numbers of people diseased and dying from this virus, may require delivering heat-stable vaccine beyond cold chains, creative financing to reduce prices, and multivalent vaccines.

Nicotine effects on proliferation and the bombesin-like peptide autocrine system in human small cell lung carcinoma SHP77 cells in culture

OBJECTIVES

To determine whether nicotine affects the proliferation and expression of the bombesin-like peptide autocrine system in human small cell lung carcinoma (SCLC) SHP77 cells compared with nonmalignant human bronchial epithelial BEAS 2B cells as non-neuroendocrine controls.

METHODS

Human lung cells were cultured in defined serum-free medium with various concentrations of nicotine added for various times. Proliferation was measured by cell counts and colorimetric assay, bombesin-like peptide receptor expression was assayed by specific binding assays and quantitative competitive PCR, and bombesin-like peptides determined by ELISA.

RESULTS

Nicotine significantly stimulated the growth of human SCLC SHP77 and NCI-H865 cells, but not BEAS 2B cells. Bombesin-like peptide receptor specific binding and mRNA expression were not affected by nicotine exposure in SHP77 cells or BEAS 2B cells. An increase in SHP77 cellular bombesin-like peptide content was observed.

CONCLUSIONS

Human SCLC SHP77 cells express the components of the bombesin-like peptide autocrine system. Increased proliferation in the presence of nicotine may be due in part to increased levels of bombesin-like peptides in SHP77 cultured in nicotine. Nicotine effects on nonmalignant pulmonary neuroendocrine cells may provide additional insight into how nicotine itself may promote lung carcinogenesis.

Nonsurgical treatment of platysmal bands with injection of botulinum toxin A

Botulinum toxin A has been used therapeutically in humans for over 20 years for a variety of medical indications. For the past 7 years, the author has injected it for cosmetic purposes in a variety of muscles of the head and neck. Fifty patient-injections of the platysma muscle were performed in an attempt to correct platysmal banding. An improvement was seen in all patients who presented to the office for follow-up in a timely manner (44 injections). Results were limited by redundant skin. No incidence of dysphagia or airway obstruction was encountered. The only complication noted was bruising. Although at least a small improvement in platysmal banding was seen in all patients, in no patient was there evidence of lifting of the lower face. All results were temporary.

[World-wide status of hepatitis B vaccination 1998]

In 1991 WHO recommended that all countries include HB vaccine into their routine childhood immunization programmes. By 1998, more than 90 countries have included HB vaccine as routine antigen in their national programmes. These countries include about half of the world's children and about 70% of the world's carriers. The WHO target is to prevent 80% of new HBV carriers in children by the year 2001 by adding the vaccine into routine immunization. The vaccine has proven to be 85% to 95% effective in preventing the chronic carrier state in population based studies from many countries. Studies in Taiwan have already shown a direct reduction of liver cancer in immunized children. The major remaining problem is to develop financial mechanisms to allow the children in the poorest countries to benefit from this important vaccine.

[World-wide epidemiology of hepatitis B]

Hepatitis B is one of the major infectious diseases of mankind with 350,000,000 chronic carriers at high risk of death from cirrhosis and primary liver cancer. The probability of becoming a chronic HBV carrier following infection depends primarily on age, and ranges from 70% following mother to child transmission to less than 10% following adult infection. The world is conceptually divided into regions of high, intermediate, and low endemicity, with predominant modes of transmission differing by region. In Asia and Africa, most transmission occurs among children, whereas in Western Europe and North America most transmission occurs during early adult life due to lifestyle, occupational exposures, or exposures within ethnic groups where the virus is endemic.

Status of hepatitis B immunization programmes in 1998

More than 90 countries have now included hepatitis B (HB) immunization into their National Immunization Programmes as a routine vaccine given to all infants and/or adolescents and many additional countries are planning for the introduction in the next two years. These countries include all industrial countries except the United Kingdom, Ireland, The Netherlands, the Scandinavian countries and Japan. Countries with routine HB immunization include about 45% of surviving new-borns, but almost 70% of hepatitis B virus carriers live in countries with routine HB programmes. Population based studies of HB immunization from around the world are now being reported with as long as 10 to 15 years of follow-up, showing a reduction of the chronic HB carrier prevalence from high (8% or greater) to low (less than 2%) endemicity in immunized cohorts of infants. Reductions in the price of HB vaccines, a significant increase in the number of producers and the advent of combination vaccines including an HB component will make the vaccine available to more children world wide, but economic constraints continue to hamper introduction of this vaccine to the children in the poorest countries.

Diplopia following transconjunctival blepharoplasty

The resurgence of popularity of the transconjunctival approach to lower eyelid fat removal as a component of cosmetic blepharoplasty has been highlighted by a number of publications in recent years. There has been, however, minimal discussion in the literature of the complications of this procedure. Although the mechanism of muscle injury is similar in transcutaneous and transconjunctival surgery, there is a much more direct route to the inferior extraocular musculature via the latter approach. Herein, we present a series of six patients with diplopia status post-transconjunctival lower eyelid blepharoplasty referred to the Manhattan Eye, Ear, and Throat Hospital for evaluation. Transconjunctival lower lid blepharoplasty was performed as a primary procedure in four patients and as a secondary procedure following transcutaneous blepharoplasty in two patients. Patients were evaluated with ocular examination and orthoptic measurements. Magnetic resonance imaging was obtained in two cases. The inferior rectus and inferior oblique muscles were found to be equally injured in these cases (4 of 6), and the lateral rectus was encountered in one case. Two patients required strabismus surgery to correct their diplopia, whereas four patients improved with observation alone. The possible etiologies of postoperative diplopia following transconjunctival lower lid blepharoplasty are manifold. Mechanisms of extraocular muscle injury may include intramuscular hemorrhage and edema, cicatricial changes within the muscle, and accidental incorporation of extraocular muscle in closure of orbital septum. Avoidance of these complications is probably best achieved through intimate understanding on the part of the surgeon of eyelid anatomy from the transconjunctival perspective.

Hepatitis viruses and the neonate

Great progress has been made in the last 10 years in the understanding of the various types of viral hepatitis, and new viruses, concepts, therapies, preventive measures, and control strategies have been recognized. Even more agents, vaccines, and drugs will be discovered or developed in the future, and pediatricians increasingly will be expected to provide guidance to patients and to the community on the importance and use of these new tools.

Clinical correlates of bombesin-like peptide receptor subtype expression in human lung cancer cells

The importance of the expression of the autocrine growth system for bombesin-like peptides (BLPS) to the biological behavior of human lung cancer has not been determined. Three BLP receptor subtypes have been identified in human lung and lung cancer cells: gastrin-releasing peptide (GRP) receptor, neuromedin B (NMB) receptor, and bombesin receptor subtype 3 (BRS-3). The goals of this study were: (1) to determine BLP receptor subtype expression by human lung cancer cell lines by RT/PCR; (2) to evaluate possible clinical correlates of characteristics of the patients from whom the cell lines were derived with patterns of BLP receptor expression. Degenerate PCR primers were designed to amplify all known BLP receptors and yielded products from 19/20 small cell lung carcinoma (SCLC) and 12/13 non-small cell lung carcinoma (NSCLC) cell lines. GRP receptor was the most commonly expressed BLP receptor subtype, being detected in 17/20 SCLC and 11/13 NSCLC. Eleven of 20 SCLC expressed NMB receptors, and 5/20 expressed BRS-3, compared with 4/13 and 1/13, respectively, in NSCLC cell lines. Evaluation of the clinical data of the patients from whom the cell lines were derived revealed expected age, sex, smoking history and survival based on histology and stage. Patients from whom cell lines expressed GRP receptor experienced a better survival than those whose cell lines did not (367 +/- 274 days vs. 211 +/- 114 days), but the results were not statistically significant. RT/PCR analysis is a feasible, sensitive and specific means of determining BLP receptor expression in lung cancer cells and may yield prognostic information in patient tissue.

Nonconstitutive expression of the gastrin-releasing peptide autocrine growth system in human small cell lung carcinoma NCI-H345 cells

Constitutive, unregulated autocrine growth is thought to be an important mechanism whereby cancer cells gain a proliferative advantage over nonmalignant cells. The question addressed here was whether the autocrine growth system for gastrin-releasing peptide (GRP) in human small cell lung carcinoma cells is, in fact, always expressed in a constitutive, unregulated fashion. Lag, rapid, and plateau growth states were defined for small cell lung carcinoma NCI-H345 cells based on periods during which they expressed different growth rates after plating as single cell suspensions. Immunoreactive GRP in the conditioned medium and in NCI-H345 cells harvested during each of these growth states, as well as cell DNA content, GRP mRNA expression, specific 125I-GRP uptake, specific 125I-GRP binding to solubilized membranes, and GRP and neuromedin B receptor mRNA expression by reverse transcription-PCR were analyzed. Maximal levels of GRP expression were observed during the lag growth state, with the highest concentration of immunoreactive GRP in the conditioned medium during the rapid growth state. Specific 125I-GRP uptake and binding were also highest during the lag growth state; however, GRP receptor mRNA did not significantly change. In contrast to prevailing concepts, these studies support the conclusion that the expression of the GRP autocrine growth system in NCI-H345 cells is indeed regulated. Furthermore, the components are maximally expressed before rapid growth begins, suggesting that other mechanisms are activated to support the actual proliferation.

Oncogenic signaling

Cancer develops when one or more cells begin to grow uncontrollably, presumably as a result of alterations in the highly regulated processes of normal cell division. These changes may result from germline or somatic mutations in genes that control normal cell proliferation, resulting in oncogenes. Oncogenes--originally defined as viral genes that transformed mammalian host cells--code for proteins with diverse functions. Antioncogenes, or tumor-suppressor genes, code for proteins acting as brakes in the cell cycle. Mutations in or deletions of these genes release the brakes. An overview of cellular signaling pathways, how they may be altered in cancers, and recently reported clinical implications of abnormal expression of some oncogenes and tumor-suppressor genes will be presented here.

Bombesin-like peptide receptors in human bronchial epithelial cells

Northern blot and RNAse protection assays previously failed to detect bombesin-like peptide (BLP) receptors in normal human lung tissue, but by RT/PCR cultured human bronchial epithelial (HBE) cells expressed all three BLP receptor subtypes, predominantly neuromedin B (NMB) receptor. By RT/PCR, we found expression of all three BLP receptor subtypes by human lung tissue and confirmed NMB receptor expression in six out of six HBE samples. However, transformed HBE BEAS B2B cells expressed only gastrin-releasing peptide (GRP) receptors; saturable, high-affinity (Kd = 3.5 nM) specific [125I]GRP binding confirmed functional GRP receptor, with M(r) = 75 kDa and immunologic cross-reactivity with GRP receptor from human small-cell lung carcinoma (SCLC) NCI-H345 cells. Altered regulation of BLP receptors may accompany transformation of normal lung cells to cancer.

Properties of classic protein kinase C in human small cell lung carcinoma NCI-H345 cells

Bombesin-like peptides (BLPs) activate protein kinase C (PKC), which leads to proliferation in nonmalignant Swiss 3T3 cells. The purpose of this study was to determine if PKC expression in the classic human small cell lung carcinoma NCI-H345 cell line, which has an autocrine growth loop involving BLPs, exhibited unique properties that could result in malignant behavior. PKC activity and phorbol dibutyrate binding in NCI-H345 cells had properties similar to other reports. PKC activity in the cytosolic fraction increased to 100% as cells proliferated through lag, log, and plateau growth states. However, during the first 3 days after plating (lag growth state), 40-50% of the PKC activity was membrane associated, indicating a substantial portion in an activated form, possibly a result of BLP autocrine stimulation. NCI-H345 cells expressed the PKC isoenzymes alpha, beta, delta, sigma, and eta, but not gamma or epsilon, a pattern different from Swiss 3T3 cells or normal brain. further characterization of the Ca2+/phospholipid-dependent (classic) PKC isoenzymes, alpha and beta, showed that PKC beta was predominantly cytosolic (80%) as expected, but PKC alpha was primarily membrane associated (80-90%). Exposure of NCI-H345 cells to 200 nm phorbol 12-myristyl 13-acetate rapidly (within 2 min) decreased cytosolic PKC activity, with no change in the particulate activity, but did not alter [3H]-thymidine incorporation or subcellular distribution of PKC alpha or beta by Western blot. These results suggest altered PKC regulation in human small cell lung carcinoma NCI-H345 cells, which could contribute to their malignant behavior.

Epidemiology and prevention of hepatitis A in travelers

OBJECTIVE

To assess the risk of hepatitis A in international travelers and to recommend preventive measures.

DATA SOURCES

Index Medicus, 1974 through 1983; MEDLINE, 1984 through 1993; and unpublished data of the Centers for Disease Control and Prevention.

STUDY SELECTION

Review of all retrospective and cohort studies on hepatitis A and other vaccine-preventable diseases in travelers, of seroepidemiologic surveys of hepatitis A virus (HAV) antibodies in travelers, of data on the various hepatitis A vaccines, of economic analyses, and of recommendations of recognized organizations.

DATA EXTRACTION

Independent analysis by multiple observers.

DATA SYNTHESIS

The incidence rate for unprotected travelers, including those staying in luxury hotels, is estimated to be three per 1000 travelers per month of stay in a developing country. Persons eating and drinking under poor hygienic conditions have a rate of 20/1000 per month. This makes hepatitis A the most frequent infection in travelers that may be prevented by immunization. In many industrialized countries persons born after 1945 have an HAV antibody seroprevalence (immunity) of less than 20%. New inactivated HAV vaccines induce protective antibodies in more than 95% of recipients and offer protection estimated to last for 10 years or more, whereas protection by immune globulin lasts only 3 to 5 months.

CONCLUSIONS

Hepatitis A vaccine, or immune globulin where HAV vaccine is not available, is recommended for all nonimmune travelers visiting developing countries. Prescreening for antibodies to HAV in travelers living in countries with low prevalence is usually not necessary in persons born after 1945.

Human melanoma cells express functional endothelin-1 receptors

Current evidence suggests that endothelium-derived factors enhance human melanoma vascular invasion. Therefore, we studied human melanoma cell expression of receptors to the endothelium-derived peptide, endothelin-1 (ET-1), and determined if they respond to ET-1 with proliferation and chemokinesis. Human metastatic melanoma cell lines were found to have specific, saturable, high affinity ET-1 binding. Northern analysis and competitive inhibition studies confirmed that melanoma cells express the ETB receptor isoform. Ten nanomolar ET-1 caused an 8.2 to 25.5-fold increase in intracellular free calcium. ET-1 was found to be a weak mitogen for melanoma cells, however, melanoma cell chemokinesis was significantly increased by ET-1. These data suggest that ET-1 may be involved in providing a chemokinetic and growth factor environment that enhances perivascular proliferation and invasiveness of melanoma cells.

Novel bombesin-like peptide binding proteins from lung

Gastrin-releasing peptide (GRP) and other bombesin-like peptides (BLP) play an important role in lung development, response to injury, and carcinogenesis. However, the mRNAs from previously cloned BLP receptors are not detectable on Northern blots of normal lung. The purpose of this study was to isolate and characterize BLP binding proteins from normal mouse lung. Soluble cytoplasmic and detergent-solubilized membrane fractions were prepared from mouse lung and evaluated for specific 125I-GRP binding. Unexpectedly, not only the solubilized membrane but also the soluble cytoplasmic fractions demonstrated saturable, high-affinity, specific GRP binding activity with Kd = 1.6 nM, Bmax = 135 fmol/mg protein and Kd = 7.5 nM, Bmax = 323 fmol/mg protein, respectively. BLP binding proteins were isolated using GRP14-27 affinity chromatography and analyzed by SDS-PAGE. In each fraction, a major unique band of approximate M(r) = 70 kD was obtained and flanked by two weaker bands of approximate M(r) = 65 and 75 kD. Preincubating samples of the cytoplasmic fraction with various neuropeptides demonstrated specificity in that only incubation with GRP14-27, the bioactive portion of the molecule, blocked affinity purification of these BLP binding proteins. The BLP binding proteins isolated from the cytoplasmic fraction were purified by HPLC, digested with trypsin, and sequenced via Edman degradation. These BLP binding proteins yielded peptides with the sequences IXGIYTDGQNTPXG and RAIMVEXXSEAXXSLLTP, both of which are unique compared with the GenBank/EMBL data base.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum melatonin levels in melanoma patients after repeated oral administration

The goal of this study was to determine the effect of oral melatonin in divided doses on plasma melatonin levels in patients with metastatic melanoma. Hourly blood samples were obtained from five patients for 24 h prior to melatonin administration and for 24 h during oral administration of melatonin, 50 mg every 4 h. In two of the five patients, the expected nocturnal plasma melatonin peak was observed. Oral melatonin was well absorbed. Plasma melatonin levels exhibited six peaks and troughs, were two to four-fold higher during peaks than troughs, and remained more than 25 times higher than peak pretreatment melatonin levels, even during troughs. Divided oral doses of melatonin were well tolerated and maintained plasma melatonin levels 25-80 times higher than endogenous peak values.

Novel soluble, high-affinity gastrin-releasing peptide binding proteins in Swiss 3T3 fibroblasts

Swiss 3T3 cells contained substantial amounts of soluble and specific [125I]GRP binders. Like the membrane-associated GRP receptor, they were of high affinity, saturable, bound to GRP(14-27) affinity gels, and exhibited specificity for GRP(14-27) binding. They differed in that acid or freezing destroyed specific binding, specific binding exhibited different time and temperature effects, no detergent was required for their solubilization, ammonium sulfate fractionation yielded different profiles, the M(rs) were lower, GRP(1-16) also blocked binding, and a polyclonal anti-GRP receptor antiserum did not bind on Western blots. The isolated, soluble GRP binding protein(s) rapidly degraded [125I]GRP. These soluble GRP binding proteins may play a role in the regulation of the mitogenic effects of GRP on these cells.

Melatonin interactions with cultured murine B16 melanoma cells

Both in vitro and in vivo observations have suggested that melatonin modulates malignant cell growth. The present studies aimed to characterize the interactions of melatonin with cultured murine B16 melanoma cells. Time- and temperature-dependent specific melatonin accumulation by B16 murine melanoma cells was observed. B16 cells possessed a high affinity binding site (KD = 1.4 nM) which exhibited structural specificity in its affinity for analogues of melatonin (melatonin > 6-hydroxymelatonin = N-acetyl-5-hydroxytryptamine > 5-methoxytryptamine >> 5-hydroxytryptamine). Evidence for a lower affinity uptake system without structural specificity was also observed. Ninety-five per cent of the specific cell-associated melatonin in B16 cells was present in the soluble subcellular fraction of lysed cells; more than 97% of the cell-associated radioactivity was authentic melatonin. When the solubilized cell extracts from the binding assay were analysed by gel filtration immediately, all of the bound counts eluted at the void volume. Continuous exposure to melatonin for 48-120 h did not affect B16 cell proliferation as determined by cell counts, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay or [3H]thymidine incorporation. After 8-h pulse exposures to melatonin daily for 3 days, a 15% stimulation of B16 cell proliferation (p < 0.02) was observed at melatonin concentrations of 0.1 and 1 nM. The anti-oestrogen, tamoxifen, inhibited B16 cell growth and increased specific melatonin accumulation by B16 cells at 1 x 10(-6) M (p < 0.02). Cultured B16 murine melanoma cells possessed a specific, high affinity uptake system for melatonin which appeared to be altered by anti-oestrogen exposure.

Effect of a hepatitis B vaccination program on the prevalence of hepatitis B virus infection

In April 1991, surveys for serologic evidence of hepatitis B virus (HBV) infection were conducted among 3- to 4-year-old children born after a hepatitis B immunization program of newborns began and among 6- to 11-year-old children targeted for early childhood vaccination in American Samoa. Compared with 3- to 4-year-olds tested in 1991, children tested at baseline in 1985 were more likely to have been infected with HBV (5/40 vs. 2/93; prevalence ratio [PR] = 5.8, 95% confidence limits [CL] = 1.2, 28.7) and to have chronic infection with HBV (3/40 vs. 0/95; PR = undefined, lower CL = 1.2). Compared with 6- to 11-year-olds tested in 1991, children in 1985 were more likely to have been infected with HBV (32/121 vs. 53/386; PR = 1.9, CL = 1.3, 2.8) and to have chronic infection with HBV (8/121 vs. 7/386; PR = 3.6, CL = 1.3, 9.8). The incorporation of hepatitis B vaccine into routine childhood vaccination schedules can prevent acute and chronic HBV infection in areas of high endemicity.

Progress on the control of hepatitis B infection through immunisation

Hepatitis B virus (HBV) infection and its sequelae, one of the major diseases of mankind, is now a disease preventable by vaccine. During the last few years, the price of these vaccines has fallen to the point where widespread use in infant immunisation programmes is feasible. This paper reports the great progress that has been made in the control of HBV infection and describes the targets that must be met if HBV control on a global basis is to be achieved.

Urinary levels of bombesin-like peptides in asymptomatic cigarette smokers: a potential risk marker for smoking-related diseases

Bombesin-like peptides (BLP) produced by pulmonary neuroendocrine cells have many physiological actions which are relevant to the pathobiology of cigarette smoking. The objectives of this study were to determine whether cigarette smokers excrete increased levels of BLP in their urine compared with nonsmokers, to determine the relationship between BLP levels in urine and bronchoalveolar lavage (BAL) fluid, and whether urinary BLP levels are merely a reflection of exposure to cigarette smoke. Simultaneous BAL fluid and urine samples were obtained from ten clinically normal smokers and 22 normal nonsmoker volunteers. Urine samples were also obtained from 39 normal smokers and 30 normal nonsmokers who did not have BAL performed. BLP levels were measured in urine and BAL fluid using an enzyme-linked immunoassay. Expired air content of carbon monoxide, which reflects recent exposure to cigarette smoke, was determined in 34 of the clinically normal smokers and correlated with urinary BLP levels. We found that, in addition to having increased BLP levels in BAL fluid (P = 0.04), asymptomatic cigarette smokers also have increased BLP levels in their urine compared with normal nonsmokers (P = 0.007). Of note, a subgroup of smokers have markedly increased BLP levels which do not overlap with the nonsmokers. Urinary BLP levels correlated with expired air content of carbon monoxide (r = 0.49, P less than 0.01). However, not all smokers with increased expired air content of carbon monoxide exhibited increased BLP levels. Finally, all smokers with detectable BLP levels in BAL fluid had detectable urinary BLP levels, and there was a positive correlation between BLP levels in urine and BAL fluid (r = 0.625, P less than 0.001). We conclude that a subgroup of asymptomatic cigarette smokers exhibited increased BLP levels, measurable in both urine and BAL fluid, which precede the onset of clinically detectable disease and which are not strictly dependent on smoking intensity. We speculate that smokers with increased BLP levels may have a greater risk for smoking-related diseases.

Perspectives on the control of hepatitis A by vaccination

The availability of an inactivated hepatitis A virus (HAV) vaccine, and the development of live attenuated virus vaccines against hepatitis represent great advances in the effort to control an important cause of viral hepatitis. There are a number of ways hepatitis A vaccines could be used, depending on the epidemiology of HAV infection in the country concerned, the cost of the product, the duration of protection that the vaccine affords and its effectiveness for postexposure prophylaxis. Expert groups could recommend vaccine to individuals who are at higher risk of exposure to hepatitis A as a result of behaviour, lifestyle or occupation, or to all infants and/or adolescents. The major public health problem with hepatitis A occurs in developing countries and regions with 'transitional economies' such as Eastern Europe and certain Middle Eastern countries. These countries have high levels of viral circulation, large cohorts of susceptible older children and adults, and high rates of HAV morbidity. Given the experience with hepatitis B vaccine and the economic and political realities of global immunization policy, it is unlikely that the Expanded Programme on Immunization and traditional vaccine donors will take a great interest in HAV vaccine in the near future. Individual countries may, however, decide to use hepatitis A vaccine on a widespread basis. Model cost effectiveness studies are needed for both developing and developed countries to help decide the feasibility of such widespread use. WHO has been involved in activities relevant to hepatitis A vaccine for many years.(ABSTRACT TRUNCATED AT 250 WORDS)

Transesophageal color Doppler echocardiography of the normal St. Jude Medical mitral valve prosthesis

Transesophageal color flow Doppler findings are reported in 36 patients with a St. Jude Medical mechanical mitral valve prosthesis who had no auscultatory evidence for prosthetic valve dysfunction. Multiple jets consistent with mitral regurgitation originating from the central and lateral portion of the prosthesis were found in all patients. Maximum jet length ranged from 11 to 51 mm (mean 21 +/- 9 mm). Maximum jet area ranged from 0.2 to 4.1 cm3 (mean 1.2 +/- 0.9 cm2). The color M-mode Doppler interrogation showed two distinct components of the regurgitant jet: brief early systolic flow consistent with valve closure followed by holosystolic regurgitant flow consistent with transvalvular leakage. Four patients (11%) had a maximum regurgitant jet length exceeding 30 mm and absence of early systolic closure regurgitant flow by M-mode color imaging, suggesting clinically silent paravalvular leakage. Two pin-sized paravalvular suture line defects were confirmed in one patient at cardiac transplantation. We conclude that transesophageal echocardiography is a highly sensitive method for detection of mitral regurgitation in the St. Jude Medical mitral prosthesis. Clinically silent paravalvular leakage should be suspected if the maximum jet length exceeds 30 mm and color M-mode interrogation fails to demonstrate an early systolic closure regurgitant flow component.

Isolation of the bombesin/gastrin-releasing peptide receptor from human small cell lung carcinoma NCI-H345 cells

Purification of the gastrin-releasing peptide (GRP) or bombesin receptor has proved elusive in part due to technical difficulties. In the present studies, the problem of oxidized radioligand was avoided by the use of 125I-GRP, which was verified to be not oxidized by high performance liquid chromatography. Specific 125I-GRP binding (at 0 degrees C) to intact human small cell lung carcinoma NCI-H345 cells which had been subjected to a dilute acid wash was 6 fmol/10(6) cells. Inhibition of GRP degradation by human H345 cell membranes through the use of phenanthroline or phosphoramidon permitted the development of binding assays for the GRP receptor in detergent-solubilized crude membrane preparations. The solubilized GRP receptor exhibited saturable, high affinity (KD = 1.3 nM), temperature-dependent specific binding averaging 402 +/- 65 fmol/mg protein (mean +/- S.E. for eight separate membrane preparations with 125I-GRP concentration = 3 nM), with a Bmax = 434 fmol/mg protein using a gel filtration binding assay. That the GRP receptor had been solubilized was demonstrated by its failure to pellet when centrifuged at 100,000 x g for 60 min, its passage through a 0.22-micron filter without loss of binding activity, and its elution in the void volume of a Sephadex G-50 gel filtration column, but within the inclusion volume of a Sephacryl S-200 column (Ve/V0 = 1.1). Isolation of the GRP receptor from human H345 cell-solubilized membranes was achieved by ligand affinity chromatography. A unique 70-kDa band on silver-stained reduced sodium dodecyl sulfate-polyacrylamide gel electrophoresis was reproducibly eluted from GRP14-27 affinity columns by an acidic high salt buffer, but binding activity was denatured by these conditions. The protein nature of the GRP receptor was demonstrated by its sensitivity to proteases after isolation. In addition, two unique bands of 65 and 70 kDa were eluted from the GRP14-27 affinity column with GRP14-27 in neutral buffer, and this eluate possessed specific 125I-GRP binding with a stoichiometry of approximately 1:1. Thus, reported here is the isolation of a functional membrane-associated, saturable, high affinity GRP receptor with temperature-dependent binding from the solubilized membranes of human H345 cells.

Isolation of a gastrin releasing peptide receptor from normal rat pancreas

The presence of a putative GRP receptor on rat pancreatic particulate membranes was demonstrated by covalent cross-linking to 125I-gastrin releasing peptide (GRP), which revealed a radioactive band with Mr = 80-90 kDa on reduced SDS-PAGE. Fresh rat pancreatic membranes contained a GRP receptor which was solubilized with Triton X-100 as assessed by its failure to sediment at 100,000 x g for one hour and its ability to pass through a 0.22 mu filter. When 125I-GRP binding was studied using Sephadex G50 gel filtration chromatography to separate bound from unbound ligand, substantial amounts of 125I-GRP binding were observed in rat crude solubilized pancreatic membranes, but essentially no specific binding was observed until the crude solubilized membranes were fractionated by ammonium sulfate precipitation. Specific 125I-GRP binding was 500, 700 and 1400 fmol/mg protein, respectively, in the 0-25%, 25-50% and 50-80% saturated ammonium sulfate fractions (125I-GRP concentration = 1 nM). Specific binding was temperature dependent, saturable and of high affinity, (KD = 2.3 nM). A unique 70 kDa band was visualized by silver staining of the SDS-PAGE of eluates of GRP(14-27) affinity gel compared with eluates of control affinity gels incubated with the 25-50% (NH4)2SO4 fraction. The lower Mr than that observed with covalent cross-linking may represent the binding subunit of a larger receptor protein. This ligand-affinity isolated protein is thus a good candidate for the GRP receptor, or the binding subunit of it, from normal rat pancreas.

Cost-effectiveness of hepatitis-B vaccine in Greece. A country of intermediate HBV endemicity

We evaluated the cost-effectiveness of (a) a vaccination program for the prevention of hepatitis B; and (b) the two commercially available vaccines (Merck Sharp and Dohme; Pasteur Institute) in Greece, a country of intermediate endemicity. We examined cases of hepatitis-B infection prevented and the expected medical costs among the high-risk groups of medical and nursing students, hospital personnel, and the general population. Employing a vaccination program reduces considerably the risk of infection, especially in the high-risk groups, while it increases the total cost. The vaccines are very comparable in terms of both health and economic outcomes. Sensitivity analysis indicated that vaccine cost, incidence of hepatitis B, and compliance were the key factors for the choice of (a) whether to undertake an extensive program to prevent hepatitis-B infection and its chronic sequelae; and (b) which vaccine to administer.

Growth factors in lung cancer: possible etiologic role and clinical target

Growth factors play an important role in the pathogenesis and progression of all histologic types of lung cancer. Ideas for the exploitation of growth factors in lung cancer management are growing. The inhibition of the interaction between growth factors and their receptors, utilization of negative growth factors, interruption of the signal transduction pathways, or effecting decreased growth factor and/or receptor expression, could result in cell death, and all seem logical possibilities for new and specific treatment approaches. There can be no question that observations of the abnormal expression of growth factors have made a startling impact in every aspect of cancer research. The elucidation of their role in cell proliferation, coupled with our growing knowledge of the functions of oncogenes, has given birth to a unifying concept for the etiology of malignant transformation, which hopefully will translate into new, less toxic, more effective, and desperately needed lung cancer treatment.

Transmission of HIV, hepatitis B virus, and other bloodborne pathogens in health care settings: a review of risk factors and guidelines for prevention. World Health Organization

Recent reports of the transmission of human immunodeficiency virus (HIV) in health care settings have caused considerable public health concern. HIV as well as hepatitis B virus (HBV) and other bloodborne pathogens do constitute infectious hazards in certain settings. Transmission has been reported from patient to patient, patient to health care workers, and rarely, from health care worker to patient. Although the risk of bloodborne pathogen transmission is largely preventable, it may occur due to the use of infected blood for transfusion, the use of improperly sterilized medical or dental equipment, and accidental punctures with contaminated instruments. The risk of transmission of bloodborne pathogens is dependent on a number of factors and appears to be greater for HBV than for HIV. General guidelines for the prevention of transmission in health care settings are given, including the concept of "universal precautions", the need for adequate supplies of sterile equipment, the reduction of unnecessary injections and transfusions, and the appropriate use of hepatitis B vaccine. In addition, areas for research are highlighted that could improve understanding of transmission risks in different health situations and provide the information necessary to develop more effective measures to protect both care providers and patients.

Increased pulmonary neuroendocrine cells with bombesin-like immunoreactivity in adult patients with eosinophilic granuloma

Cigarette smoking is associated with hyperplasia of pulmonary neuroendocrine cells and variably increased levels of bombesin-like peptides in the lower respiratory tract. Because the neuropeptide bombesin is a chemoattractant for monocytes and a mitogen for 3T3 fibroblasts, we hypothesized that an excess of neuroendocrine cells and bombesin-like peptides could contribute to lung inflammation and fibrosis in certain cigarette smokers. Eosinophilic granuloma is a fibrotic lung disease of unknown etiology that in adults occurs almost invariably in cigarette smokers. We quantitated neuroendocrine cells with bombesin-like immunoreactivity in open lung biopsies from patients with eosinophilic granuloma (n = 6) and compared these with cigarette smokers (n = 6) who underwent lung resection for reasons other than primary lung disease. In addition, we compared them with patients with idiopathic pulmonary fibrosis (n = 8), a disease not associated with cigarette smoking. Finally, we also examined the mitogenic effect of bombesin on cultured human adult lung fibroblasts. The patients with eosinophilic granuloma exhibited a 10-fold increase in neuroendocrine cells with bombesin-like immunoreactivity compared to both smokers (P = 0.005) and patients with idiopathic pulmonary fibrosis (P = 0.005). In addition, bombesin produced a significant mitogenic effect on cultured human adult lung fibroblasts at concentrations of 1 nM and above. We conclude that increased numbers of pulmonary neuroendocrine cells with bombesin-like immunoreactivity are commonly found in patients with eosinophilic granuloma and, since bombesin-like peptides are chemotactic for monocytes and mitogenic for human lung fibroblasts, we speculate that neuroendocrine cell hyperplasia may be important in the pathogenesis of eosinophilic granuloma in adult cigarette smokers.

Development of recommendations for control of hepatitis B virus infections: the role of cost analysis

Hepatitis B (HBV) infection produces a number of acute and chronic consequences including fulminant hepatitis, chronic liver disease and cirrhosis. The development of safe and effective hepatitis B vaccines has led to the development of several prevention strategies based on the endemicity and primary age of infection in the population. In areas of high endemicity of infection, universal immunization of infants has been advocated and appears feasible. However, in areas of low endemicity of infection, selected high risk group immunization of adults has been recommended but has not been successful in changing infection rates. In 1981, an analysis of the economic consequences of acute and chronic HBV-related liver disease showed an expenditure of at least US$197 million for direct medical costs and US$126 million for the associated cost of work-loss. These results suggest the more widespread use of hepatitis B vaccine to prevent these high health-related costs.

Hepatitis B virus transmission between children in day care

We investigated two situations involving hepatitis B virus exposure among children in day care. In the first a 4-year-old boy who attended a day care center developed acute hepatitis B; another child at the center, who had a history of aggressive behavior (biting/scratching), was subsequently found to be a hepatitis B carrier. No other source of infection among family and other contacts was identified and no other persons at the center became infected. In the second situation a 4-year-old boy with frequently bleeding eczematous lesions was discovered to be a hepatitis B carrier after having attended a day care center for 17 months. Testing of contacts at the center revealed no transmission to other children or staff (representing 887 person months of exposure). Nationwide surveillance data showed that for the period 1983 to 1987, 161 children 1 to 4 years of age were reported with acute hepatitis B. After children with known hepatitis B risk factors were excluded, 25% (7 of 28) of children with known day care status were reported as day care attendees, a percentage comparable to national estimates of day care attendance by this age group. This is the first reported case of hepatitis B virus transmission between children in day care in the United States. Although it appears that day care transmission of hepatitis B is infrequent, further studies are needed to define the risk more accurately.

Hepatitis B virus infection among children born in the United States to Southeast Asian refugees

Since 1975 nearly 1 million persons have entered the United States from Southeast Asia, where infection with hepatitis B virus (HBV) is hyperendemic. To evaluate the prevalence and patterns of transmission of HBV infection among the children of refugees from Southeast Asia, we studied 196 refugee families with 257 children born in the United States. Of 31 children born in the United States to mothers with infectious disease, 17 (55 percent) had been infected with HBV. Of 226 children whose mothers did not have infectious disease, 15 had HBV infection--a prevalence of 6.6 percent (95 percent confidence interval, 4.1 to 10.7). The risk of infection was greatest (26 percent) among children living in households with children with infectious disease (relative risk, 5.5; confidence interval, 2.3 to 13.4). Exposure to fathers or other adults with infectious disease was not significantly associated with infection. Of children from households with no persons with infectious disease, 3.9 percent (confidence interval, 1.7 to 8.8) were infected. Nearly half (46 percent) the cases of HBV infection among the U.S.-born children of refugees were not attributable to perinatal transmission from a mother with infectious disease. We conclude that child-to-child transmission may be occurring within and between households. Current recommendations to immunize the newborns of mothers with infectious disease are not sufficient to protect all U.S.-born children of Southeast Asian refugees from HBV infection early in life, when the risk of chronic sequelae and premature death is highest. We recommend that the HBV vaccination policy be expanded to include all newborns of Southeast Asian immigrants.

Increased levels of bombesin-like peptides in the lower respiratory tract of asymptomatic cigarette smokers

Bombesin-related peptides are growth factors for a variety of cells, including normal human bronchial epithelial cells. An ELISA for bombesin-like peptides (BLP) has been devised using the MAb BBC353, which is specific for the biologically active carboxy-terminal fragment shared by all known BLP. Using this ELISA, we measured bronchoalveolar lavage (BAL) fluid levels of BLP in normal cigarette smokers (n = 15) and normal nonsmokers (n = 18). Smokers' BAL fluid contained increased levels of BLP, whether expressed in terms of BAL fluid volume (P = 0.0001) or protein content (P less than 0.05). BLP levels did not correlate with any cellular constituent in the BAL fluid but immunostaining of lung tissue with BBC353 revealed an intense specific staining of neuroendocrine cells, implying these as a potential source. Two peaks of bombesin-like immunoreactivity were purified using sequential reverse phase and gel filtration HPLC. Both BLP have apparent molecular weights similar to gastrin-releasing peptide on gel filtration HPLC analysis. However, the amino acid composition of these BLP is different from that of gastrin-releasing peptide or neuromedin B, the only known mammalian forms of BLP, suggesting either incomplete purification or novel peptides. Sequence analysis could not be performed due to blocking groups at the amino terminus of these peptides. Our data demonstrate that cigarette smoking is associated with increased levels of pulmonary BLP and imply a potential role for these neuropeptides in the lung's response to tobacco smoke.

Hepatitis B infection in the United States. Recent trends and future strategies for control

Viral hepatitis is the second most common reportable infectious disease in the United States, with hepatitis B accounting for about 45 percent of cases. Although approximately 25,000 cases of hepatitis B are reported to the Centers for Disease Control each year, it is estimated that there are actually about 300,000 annual infections (up from 200,000 in the early 1980s). This increase has occurred despite the availability of a safe and effective hepatitis B vaccine since 1982. Hepatitis B occurs primarily in young adults because of lifestyle or occupationally related exposure. Reported cases in homosexual men have decreased, probably because of changes in behavior related to the acquired immunodeficiency syndrome epidemic. Cases due to heterosexual transmission and intravenous drug use are increasing. The proportion of cases in health care workers has decreased, possibly because 30 to 40 percent of high-risk health care workers have been vaccinated. Because of the increase in hepatitis B infection, the strategy of controlling this disease by vaccinating high-risk groups must be reconsidered. Alternative strategies include selective or universal immunization of infants or adolescents. Although integrating hepatitis B vaccine into infant immunization programs takes advantage of the existing system, it would not lead to measurable disease reduction for two decades. Immunizing adolescents would more rapidly reduce the incidence of hepatitis B, but currently no structured health care setting reaches them.

Role of folate binding proteins in folate metabolism

The essential role of folates in cellular biochemistry is well established, but the nature of the participation by folate-binding proteins has been disputed. This review will define folate-binding proteins and distinguish them from low-affinity, nonspecific folate binders and folate-dependent intracellular enzymes. We outline changes in plasma folate-binding proteins in various clinical states, review their postulated functions, detail the biochemistry of mammalian soluble folate-binding proteins and their membrane-bound immunologically cross-reactive possible precursors, and present evidence that the latter proteins may function as the physiologic folate receptors and intracellular regulators of folate coenzyme availability.

Folate (pteroylglutamate) uptake in human red blood cells, erythroid precursors and KB cells at high extracellular folate concentrations. Evidence against a role for specific folate-binding and transport proteins

Membrane-associated folate (pteroylglutamate, PteGlu)-binding proteins (FBPs) play an important role as PteGlu-transport proteins in malignant and normal human cells. Since high extracellular folate (PteGlu) concentrations (EFC) profoundly influenced uptake and toxicity of the anti-PteGlu methotrexate in malignant KB cells, we studied human cells to determine additional mechanisms for PteGlu uptake when the EFC was varied. At low EFC (less than 10 nM), the predominant mechanism for folate uptake in mature erythrocytes was through binding to externally oriented FBPs which were quantitatively insignificant (4-6 orders of magnitude lower) and of no apparent physiological relevance when compared with KB cells. However, the predominant mechanism of PteGlu accumulation at high EFC [10-250 nM] in intact erythrocytes and sealed right-side-out (RSO) ghosts was not FBP-mediated and non-specific. This conclusion was based on the findings that radiolabelled PteGlu uptake: (i) continued even in the presence of a 1000-fold excess of unlabelled PteGlu and was linear and not saturable up to 250 nM; (ii) was two-fold higher at pH 4.5 than 7.5; (iii) was less than 2-fold increased at 37 degrees C compared with 4 degrees C; and (iv) was unaffected after trypsin-mediated proteolysis of greater than 75% FBPs. The [3H]PteGlu and 125I-PteGlu (histamine derivative) accumulated intracellularly through the non-specific PteGlu-uptake mechanism was unaltered biochemically and in a soluble compartment. Raising the EFC 500-fold higher than controls during erythropoiesis in vitro resulted in reversal of the expected anti-(placental folate-receptor)-antiserum-induced megaloblastic changes in orthochromatic normoblasts derived from burst-forming unit-erythroid colonies. Furthermore, at EFC greater than 0.1 microM, KB-cell accumulation of [3H]PteGlu was also predominantly through a mechanism that did not involve specific FBPs. Thus, at high EFC, a major component of PteGlu transport in human cells is not mediated through FBPs and is likely to be a passive diffusion process.

Hepatitis D virus infection in Illinois state facilities for the developmentally disabled. Epidemiology and clinical manifestations

OBJECTIVE

To define the epidemiology and clinical manifestations of hepatitis D virus infection in an institutionalized population.

DESIGN

A case-control study of hepatitis B carriers with and without serologic evidence of hepatitis D virus infection. Demographic, institutional, and medical data were obtained through questionnaires and chart review. Clinical status was assessed by liver function assays.

SETTING

Thirteen Illinois state facilities for the developmentally disabled.

PARTICIPANTS

Clients (238) who were hepatitis B carriers.

RESULTS

Antibody to hepatitis D virus (anti-HDV) was detected in 71 of 238 (30%) hepatitis B carriers. Nine of thirteen facilities housed positive clients. Previous residence at one facility, designated B, was the strongest correlate of anti-HDV positivity; 85% of positive persons had lived there compared with 16% of negative controls (odds ratio 28.3 [95% CI, 13.2 to 60.7], P less than 0.001). Past hepatitis episodes were more common among anti-HDV-positive clients (37% compared with 7%) (odds ratio, 7.5 [95% CI, 3.0 to 19.1], P less than 0.001) and occurred mainly at facility B from 1950 to 1975. Liver function tests were infrequently abnormal among anti-HDV-positive clients.

CONCLUSIONS

Results show widespread hepatitis D virus infection in our institutionalized population and suggest that transmission occurred mainly in the past at the overcrowded facility B. The low prevalence of laboratory evidence of chronic liver disease in the anti-HDV-positive clients may be explained by increased mortality among those originally infected from 1950 to 1975.

Global control of hepatitis B through vaccination: role of hepatitis B vaccine in the Expanded Programme on Immunization

Hepatitis B is a disease that affects people throughout the world, and over 200 million are persistent carriers of the hepatitis B virus (HBV). The chronic sequelae of this infection include chronic active hepatitis, cirrhosis, and primary hepatocellular carcinoma. The development of safe and highly effective hepatitis B vaccines now provides the means by which HBV infection, including the HBV chronic carrier state, can be prevented and the related mortality significantly reduced. The cost of these vaccines has significantly decreased and will soon approach levels at which the cost-effectiveness (cost per death prevented) of hepatitis B vaccine will be similar to that of other childhood vaccines. Integration of hepatitis B vaccine into the Expanded Programme on Immunization for mass vaccination of infants in areas where HBV infection is endemic and morbidity is high would be the most effective means of providing the coverage necessary for effective control and prevention.