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W Miller

Publications and source records attributed to W Miller.

At least 145 records · Page 8Linked to original sources
PubMed1993

Safety, tolerability, and immunogenicity of an inactivated hepatitis A vaccine: effects of single and booster injections, and comparison to administration of immune globulin.

Hepatitis A virus (HAV) infection in adults is often symptomatic and disabling. The present article summarizes our experience with phase 2 studies of an inactivated hepatitis A virus vaccine. Pre- and post-exposure prophylaxis with immune globulin (IG) is only effective for 4-6 months. We compared the safety, tolerability, and immunogenicity of a single i.m. injection of IG with single and booster doses of an inactivated hepatitis A virus vaccine (iHAV) in adults. A total of 75 healthy volunteers (aged 18-50 years) were evaluated in two separate studies. The first included 15 volunteers who received 25 units iHAV i.m. at 0 and 24 weeks. The second, a randomly controlled study, consisted of three groups receiving 25 units iHAV i.m. at 0, 1, and 6 months, or at 0, 2, and 6 months, or 0.06 ml/kg IG i.m. given once. Anti-HAV seroconversion was measured by radioimmunoassay (RIA). After IG injection, anti-HAV seroconversion occurred in 100% of recipients at week 1, declining to 10% at week 12, and 0% by week 20. In contrast, after a single 25-unit dose, RIA seropositivity in iHAV vaccines was 73% by week 2, reaching 100% by week 5, and persisted in all up to week 24, at which time anti-HAV geometric mean titers (GMT) were 2-fold higher than those seen at week 1 after IG. Administration of a booster dose given 1 or 2 months after primary immunization did not significantly improve the quantitative anti-HAV response at 6 months as compared to the effect of the primary dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Anatomy of a trial: a historical view of the Monroe inactivated hepatitis A protective efficacy trial.

The performance of vaccine protective efficacy trials is often more complex than reports of final results suggest. The current article reviews the background, planning and preparations for the Monroe, NY, protective efficacy trial of a formalin-inactivated, alum-adjuvanted hepatitis A vaccine (VAQTA, manufactured by Merck Research Laboratories). The vaccine trial was carried out at Kiryas Joel, a Hasidic Jewish community which had experienced numerous annual outbreaks in a local environment with similarities to day-care centers. Careful communication, and cooperation of community leadership, a flexible technical resource team, and knowledge of an epidemic already ongoing in a sister community whose members were due to arrive for summer holidays, permitted rapid and efficient completion of the trial with a striking demonstration of protection after a single vaccine dose.

Clinical Protocols↗
PubMed1993

Building multiple alignments from pairwise alignments.

Given a family of related sequences, one can first determine alignments between various pairs of those sequences, then construct a simultaneous alignment of all the sequences that is determined in a natural manner by the set of pairwise alignments. This approach is sometimes effective for exposing the existence and locations of conserved regions, which can then be aligned by more sensitive multiple-alignment methods. This paper presents an efficient algorithm for constructing a multiple alignment from a set of pairwise alignments.

Algorithms↗
PubMed1993

Locating well-conserved regions within a pairwise alignment.

Within a single alignment of two DNA sequences or two protein sequences, some regions may be much better conserved than others. Such strong conservation may reveal a region that possesses an important function. When alignments are so long that it is infeasible, or at least undesirable, to inspect them in complete detail, it is helpful to have an automatic process that computes information about the varying degree of conservation along the alignment and displays the information in a graphical representation that is readily assimilated. This paper presents methods for computing several such 'robustness measures' at each position of a given alignment. These methods are all very space-efficient; they use only space proportional to the sum of the two sequence lengths. To illustrate their effectiveness, one of the methods is used to locate particularly well-conserved regions in the beta-globin gene locus control region and in the 5' flank of the gamma-globin gene.

Algorithms↗
PubMed1993

Use of long sequence alignments to study the evolution and regulation of mammalian globin gene clusters.

The determination of long segments of DNA sequences encompassing the beta- and alpha-globin gene clusters has provided an unprecedented data base for analysis of genome evolution and regulation of gene clusters. A newly developed computer tool kit generates local alignments between such long sequences in a space-efficient manner, helps the user analyze the alignments effectively, and finds consistently aligning blocks of sequences in multiple pairwise comparisons. Such sequence analyses among the beta-like globin gene clusters of human, galago, rabbit, and mouse have revealed the general patterns of evolution of this gene cluster. Alignments in the flanking regions are very useful in assigning orthologous relationships. Investigation of such matches between the mouse and human beta-like globin gene clusters has led to a reassessment of some orthologous assignments in mouse and to a revision of the proposed pathway for evolution of this gene cluster. In general, the interspersed repetitive elements have inserted independently, presumably via a retrotransposition mechanism, in the different mammalian lineages. However, some examples of ancient L1 repeats are found, including one between the epsilon- and gamma-globin genes that appears to have been in the ancestral eutherian gene cluster. Prominent matching sequences are found in a long region 5' to the epsilon-globin gene, the locus control region (LCR) that is a positive regulator of the entire gene cluster. Three-way alignments among the human, goat, and rabbit sequences can extend for > or = 3 kb in part of the LCR (DNase hypersensitive site 3), indicating that the cis-acting components of this complex regulatory region cover a long segment of DNA. In contrast to the beta-like globin gene clusters, the alpha-like globin gene clusters of many mammals occur in very G+C-rich isochores and contain prominent CpG islands. The regions between the alpha-like globin genes are evolving faster than the intergenic regions of the beta-like globin gene clusters. The contrasts between the two gene clusters can be attributed to differences in DNA metabolism in the isochore. The proximal control elements of the rabbit alpha-globin gene are located both 5' to and within the gene. All of this region is part of a prominent CpG island that may be acting as an extended, enhancer-independent promoter. One can hypothesize that the analogue to the LCR in the alpha-globin gene cluster may interface with the distinctive alpha-globin promoter in ways different from the interaction between the beta LCR and the promoters of beta-like globin genes.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Safety, tolerability and immunogenicity of a formalin-inactivated hepatitis A vaccine (VAQTA) in rural Kentucky children.

This study evaluated the immunogenicity and safety/tolerability profile of an investigational formalin-inactivated hepatitis A virus vaccine (VAQTA; Merck Research Laboratories) in 150 seronegative healthy children, 4 to 12 years old. The vaccine was derived from virus grown in infected MRC-5 cells in either roller bottles or Nunc cell factories (Nunc, Denmark). Subjects were vaccinated intramuscularly in a two dose regimen initially and at 24 weeks: Group A (n = 50) with a 12-unit dose from a roller bottle lot; Group B (n = 50) with a 25-unit dose from another roller bottle lot; and Group C (n = 50) with a 25-unit dose from a Nunc cell lot. Sera for anti-hepatitis A virus antibodies were drawn 3 weeks before vaccination and 4, 24 and 28 weeks after the first dose. Seroconversion from < 10 mIU/ml to > or = 10 mIU/ml by modified HAVAB (Abbott Laboratories) was observed in 99% of subjects at week 4 and persisted in 100% of subjects at week 28 (4 weeks after the second dose). The ranges of geometric mean titers of anti-HAV for all subjects at weeks 4, 24 and 28 were 31 to 49, 51 to 79 and 7059 to 29,609 mIU/ml, respectively. The 12- and 25-unit dose levels of roller bottle yielded similar geometric mean titers. The rise in geometric mean titers after the booster dose was > 120-fold and was highest in the recipients of the 25-unit Nunc cell lot (P < 0.05 for Group C vs. B).(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1993

Cytomegalovirus pneumonia after bone marrow transplantation. Risk factors and response to therapy.

Cytomegalovirus pneumonia complicated bone marrow transplantation in 75 (63 allogeneic and 12 autologous) of 1136 recipients (Kaplan-Meier incidence 8.8%). CMV pneumonia occurred more frequently in allogeneic (12.4%) than autologous recipients (3.3%). Increased risk for CMV pneumonia was observed in allogeneic recipients who were seropositive (relative risk = 2.9), older age (RR = 1.4 per decade), those conditioned with total-body irradiation (RR = 2.7), who received antithymocyte globulin (RR = 2.9) or T cell-depleted marrow (RR = 2.7) or who had CMV viruria (RR = 4.0) or viremia (RR = 5.9). Autologous recipients were also at increased risk if they were seropositive (RR = 6.1), or developed viruria (RR = 7.0) or viremia (RR = 15.4). Thirteen of 14 untreated patients died without improvement. Prognosis was poor in patients who were ventilator-dependent at initiation of therapy (median survival 17 days), with only 1 long-term survivor. In contrast, patients ventilator-independent at initiation of therapy with ganciclovir and immunoglobulin (n = 22) had a median survival of > 274 days, with 9 long-term survivors. Ganciclovir alone or acyclovir with immunoglobulin in ventilator-independent patients was less effective (median survivals 80 and 10 days, respectively). Overall, 10 of 75 patients were surviving 10-73 months (median 47) from diagnosis; 9 of these were ventilator-independent at initiation of therapy and received ganciclovir with immunoglobulin. CMV pneumonia was less common, but was severe in autologous recipients, with only 2 of 12 surviving. CMV pneumonia remains a prominent cause of death following BMT. Early therapy with ganciclovir and immunoglobulin before respiratory failure supervenes may improve survival.

Acyclovir↗
PubMed1993

Positive and negative regulatory elements of the rabbit embryonic epsilon-globin gene revealed by an improved multiple alignment program and functional analysis.

The epsilon-globin genes of mammals are expressed in early embryos, but are silenced during fetal and adult erythropoiesis. As a guide to defining the regulatory elements involved in this developmental switch, we have searched the sequences of epsilon-globin genes from different mammals for highly conserved segments. The search was facilitated by the development of a new program, called yama, to generate a multiple alignment of very long sequences using an improved scoring scheme. This allowed us to generate a multiple alignment of sequences from a more divergent group than previously analyzed, as demonstrated here for representatives of four mammalian orders. In parallel experiments, we constructed a series of deletion mutations in the 5' flank of the rabbit epsilon-globin gene and tested their effect on an epsilon-globin-luciferase hybrid reporter gene. These results show that 121 bp of 5' flank, containing CACC, CCAAT and ATA motifs, is sufficient for expression in erythroid K562 cells. Both positive and negative cis-acting control sequences are located between 218 and 394 bp 5' to the cap site, in a region previously proposed to be a silencer. The positive regulatory sequence contains conserved binding sites for the nuclear protein YY1 adjacent to another highly conserved sequence. The negative element contains a conserved sequence followed by a purine-rich segment. This analysis maps the upstream control sequences more precisely and points to a very complex regulatory scheme for this gene.

Animals↗
PubMed1993

Laparoscopic Doderlein hysterectomy: a rational alternative to traditional abdominal hysterectomy.

Nearly three of four hysterectomies are performed by abdominal incision. When laparoscopically directed dissection of the uterus adnexae and development of the bladder flap are coupled with a Doderlein vaginal hysterectomy, most of these abdominal procedures can be converted to vaginal procedures. Experience with 167 procedures has demonstrated that this new procedure can be performed safely, effectively, and efficiently. The benefits of less postoperative discomfort, resulting in shorter hospital stays and quicker return to normal activity, coupled with a reduced cosmetic defect, have been clearly demonstrated.

Adult↗
PubMed1993

Combination graft-versus-host disease prophylaxis using immunotoxin (anti-CD5-RTA [Xomazyme-CD5]) plus methotrexate and cyclosporine or prednisone after unrelated donor marrow transplantation.

Unrelated donor (URD) bone marrow transplantation (BMT) is associated with more frequent and more therapy-resistant graft-versus-host disease (GVHD). We tested an in vivo immunotoxin with direct cytolytic potency against CD5-expressing T lymphocytes (Xomazyme-CD5) for GVHD prophylaxis after URD BMT. The immunotoxin was given in vivo (0.1 mg/kg/day) for 3 weeks following transplantation in combination with methotrexate+prednisone (MXP; n = 16) or methotrexate+cyclosporine (MCX; n = 6). The 22 patients (10 phenotypically matched with their donors and 12 partially matched) received unmanipulated marrow. MXP was well tolerated, while MCX led to unacceptable nephrotoxicity, weight gain and edema. Four patients died of early complications. Thirteen of 17 evaluable patients achieved myeloid engraftment by 17-40 days (median 24 days). Acute GVHD developed in 9 of 15 evaluable patients (5 grade III/IV). Six of 8 evaluable patients developed chronic GVHD. Four patients survive 1.1-2 years after BMT. Although this immunotoxin has previously shown potency in prophylaxis of murine GVHD and therapy of human GVHD, in this trial inadequate immunosuppressive potency of the immunotoxin combinations was associated with unacceptable clinical toxicity. Aggressive immunoprophylaxis against GVHD is required to improve the success of URD BMT.

Adolescent↗
PubMed1992

Sulfoconjugation of steroids and the vascular pathway of communication in dogfish testis.

The zonal testis of the dogfish (Squalus acanthias) has proven advantageous to study biochemical changes in relation to stage of spermatogenesis, including information on steroidogenic enzymes and steroid receptors. To investigate whether sulfotransferase is part of a mechanism regulating the availability of biologically active hormone in close proximity to receptors, we measured in vitro conversion of [3H]estrone (E1) to sulfoconjugated metabolites in cytosolic subfractions of testes grossly dissected according to germ cell composition (premeiotic-PrM, meiotic-M, and postmeiotic-PoM stages). Assays were carried out in the presence of adenosine 3'-phosphate 5'-phosphosulfate (PAPS) at 22 degrees C and optimized for time (60 min) and protein (500 micrograms/ml). Michaelis-Menten kinetics and saturation analysis gave the following reaction constants for [3H]E1: Km = 0.33 microM, Vmax = 2.5 pmol/min/mg; and for PAPS: Km = 33 microM, Vmax = 1.1 pmol/min/mg; competition studies carried out in the absence or presence of 1- or 5-fold excess radioinert steroids indicated that estrogen (E2 > E1) as well as androgens (T = DHEA > 5 alpha dihydrotestosterone, DHT) were effective inhibitors. Sulfotransferase activity was found to be stage-related, being highest in PoM regions (2.31 +/- 0.24 pmol/min/mg protein) when compared to M and PrM regions (1.22 +/- 0.22 and 1.28 +/- 0.21 pmol/min/mg protein, respectively). Sulfoconjugation and the intratesticular distribution of steroid sulfates were also measured in vivo by perfusion of the intact testis with [3H]androgen or -estrogen. The pathway of blood flow via the genital artery was epigonal organ-->PoM-->M-->PrM (mature-->immature). Perfused [3H]E2, T, and DHT were all extensively metabolized in a one-pass, 1 hr perfusion, less than 10% of perfused [3H] steroid being recovered from testicular tissues as unchanged steroid. In general, recovery of polar metabolites was greater than non-polar metabolites from all three substrates. Sequential hydrolysis with glucuronidase and glusulase indicated that sulfoconjugation is a minor component (< 20%) of several "inactivating" pathways, which include glucuronide conjugation, 17-ketosteroid synthesis, and pathways leading to unidentified polar metabolites. No consistent stage-related distribution patterns were observed for any of the metabolite subfractions; however, total recovered radioactive steroid (polar plus non-polar) formed a decreasing concentration gradient from point of entry of perfusate (PoM region) to point of exit (PrM region). These data support the conclusion that access to receptors by steroid ligands may be controlled by a balance between activating and inactivating pathways.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

A new in situ hybridization technique for spliced RNA species documents the bone marrow origin of pulmonary macrophages in chronic myelogenous leukemia.

Tissue macrophages derive from monocytes of bone marrow origin. Because monocytes from patients with chronic myelogenous leukemia (CML) contain the Philadelphia chromosome (Ph), it seemed probable that tissue macrophages in CML would originate from the malignant clone. Using powerful molecular techniques, we studied pulmonary alveolar macrophages (PAM) from two patients with CML. PAM from Patient 1, a patient in chronic phase studied before bone marrow transplantation (BMT), contained the Ph by Southern blot analysis. Patient 2, an accelerated phase patient, was studied after post-BMT relapse. PAM from this patient not only contained the Ph, but also expressed the BCR/ABL message documented by a new splice junction in situ hybridization technique. This new technique allows detection of BCR/ABL mRNA and determination of splice useage in individual cells. These data confirm the continued replenishing of PAM from peripheral blood monocytes in non-BMT settings and represent the first direct evidence that tissue macrophages are derived from the malignant clone in patients with CML.

Adult↗
PubMed1992

A controlled trial of a formalin-inactivated hepatitis A vaccine in healthy children.

BACKGROUND: Although inactivated hepatitis A vaccine is known to be well tolerated and immunogenic in healthy children and adults, its efficacy has yet to be established. METHODS: To evaluate the efficacy of the hepatitis A vaccine in protecting against clinically apparent disease, we conducted a double-blind, placebo-controlled trial in an Hasidic Jewish community in upstate New York that has had recurrent outbreaks of hepatitis A. At the beginning of a summer outbreak, 1037 healthy seronegative children 2 to 16 years of age were randomly assigned to receive one intramuscular injection of a highly purified, formalin-inactivated hepatitis A vaccine or placebo. A case was defined by the presence of typical signs and symptoms, a diagnostic increase in IgM antibody to hepatitis A, and a serum concentration of alanine aminotransferase at least twice the upper limit of normal. Cases occurring greater than or equal to 50 days after the injection were included in the evaluation of efficacy. The children were followed for a mean of 103 days. RESULTS: A total of 519 children received vaccine, and 518 received placebo. The vaccine was well tolerated, with no serious adverse reactions. From day 50 after the injection, 25 cases of clinically apparent hepatitis A occurred in the placebo group and none in the vaccine group (P less than 0.001), confirming that the vaccine had 100 percent protective efficacy. Before day 21, seven cases occurred in the vaccine group and three cases in the placebo group. After that time, there were no cases among vaccine recipients and 34 cases among placebo recipients. CONCLUSIONS: The inactivated purified hepatitis A vaccine that we tested is well tolerated, and a single dose is highly protective against clinically apparent hepatitis A.

Adolescent↗
PubMed1992

Dynamic programming algorithms for biological sequence comparison.

Efficient dynamic programming algorithms are available for a broad class of protein and DNA sequence comparison problems. These algorithms require computer time proportional to the product of the lengths of the two sequences being compared [O(N2)] but require memory space proportional only to the sum of these lengths [O(N)]. Although the requirement for O(N2) time limits use of the algorithms to the largest computers when searching protein and DNA sequence databases, many other applications of these algorithms, such as calculation of distances for evolutionary trees and comparison of a new sequence to a library of sequence profiles, are well within the capabilities of desktop computers. In particular, the results of library searches with rapid searching programs, such as FASTA or BLAST, should be confirmed by performing a rigorous optimal alignment. Whereas rapid methods do not overlook significant sequence similarities, FASTA limits the number of gaps that can be inserted into an alignment, so that a rigorous alignment may extend the alignment substantially in some cases. BLAST does not allow gaps in the local regions that it reports; a calculation that allows gaps is very likely to extend the alignment substantially. Although a Monte Carlo evaluation of the statistical significance of a similarity score with a rigorous algorithm is much slower than the heuristic approach used by the RDF2 program, the dynamic programming approach should take less than 1 hr on a 386-based PC or desktop Unix workstation. For descriptive purposes, we have limited our discussion to methods for calculating similarity scores and distances that use gap penalties of the form g = rk. Nevertheless, programs for the more general case (g = q+rk) are readily available. Versions of these programs that run either on Unix workstations, IBM-PC class computers, or the Macintosh can be obtained from either of the authors.

Algorithms↗
PubMed1992

The 5' ends of LINE1 repeats in rabbit DNA define subfamilies and reveal a short sequence conserved between rabbits and humans.

The 5' ends of five full-length LINE1 (L1) repeats from the rabbit genome (L1Oc) were mapped and their nucleotide sequences determined. Computer-generated alignments showed that these five L1Oc repeats can be divided into subfamilies, each of which has a characteristic sequence upstream of the first open reading frame (ORF1). These five L1Ocs range in size from 6.5 to 7.3 kb, with 5' ends located 76 to 1125 bp upstream of ORF1. Two of these subfamilies appear to have diverged from a common ancestor at least 66 million years ago. Comparisons of the 5' ends of L1s from rabbit, human, mouse, and rat show no common sequence 5' to ORF1, except for a 22-bp sequence that is found near the beginning of all characterized full-length L1s from rabbit and human. A statistical analysis indicates that this 22-bp aligned block is highly significant. Part of this 22-bp sequence matches the microE1 binding site in immunoglobulin gene enhancers. This strong conservation suggests that the microE1 binding site may be part of a transcriptional regulatory element at the 5' ends of rabbit and human L1 repeats.

Animals↗