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The effects of thrombopoietic stimulation on megakaryocytopoiesis, platelet production, and platelet viability and function were examined in normal volunteers randomized to receive single bolus subcutaneous injections of 3 microg/kg pegylated recombinant megakaryocyte growth and development factor (PEG-rHuMGDF) or placebo in a 3:1 ratio. PEG-rHuMGDF transiently doubled circulating platelet counts, from 237 +/- 41 x 10(3)/microL to 522 +/- 90 x 10(3)/microL (P.0001), peaking on day 12. Baseline and day-12 samples showed no differences in responsiveness of platelets to adenosine diphosphate or thrombin receptor agonist peptide (P.4 in all cases); expression of platelet ligand-induced binding sites or annexin V binding sites (P.6 in both cases); or density of platelet TPO-receptors (P.5). Platelet counts normalized by day 28. The life span of autologous (111)In-labeled platelets increased from 205 +/- 18 hours (baseline) to 226 +/- 22 hours (P.01) on day 8. Platelet life span decreased from 226 +/- 22 hours (day 8) to 178 +/- 53 hours (P.05) on day 18. The theoretical basis for senescent changes in mean platelet life span was illustrated by biomathematical modeling. Platelet turnover increased from 43.9 +/- 11.9 x 10(3) platelets/microL/d (baseline) to 101 +/- 27.6 x 10(3) platelets/microL/d (P =.0009), and marrow megakaryocyte mass expanded from 37.4 +/- 18.5 fL/kg to 62 +/- 17 x 10(10) fL/kg (P =. 015). Although PEG-rHuMGDF initially increased megakaryocyte volume and ploidy, subsequently ploidy showed a transient reciprocal decrease when the platelet counts exceeded placebo values. In healthy human volunteers PEG-rHuMGDF transiently increases megakaryocytopoiesis 2-fold. Additionally, peripheral platelets expand correspondingly and exhibit normal function and viability during the ensuing 10 days. The induced perturbation in steady state thrombopoiesis resolves by 4 weeks. (Blood. 2000;95:2514-2522)

The Stanford Microarray Database (SMD) stores raw and normalized data from microarray experiments, and provides web interfaces for researchers to retrieve, analyze and visualize their data. The two immediate goals for SMD are to serve as a storage site for microarray data from ongoing research at Stanford University, and to facilitate the public dissemination of that data once published, or released by the researcher. Of paramount importance is the connection of microarray data with the biological data that pertains to the DNA deposited on the microarray (genes, clones etc.). SMD makes use of many public resources to connect expression information to the relevant biology, including SGD [Ball,C.A., Dolinski,K., Dwight,S.S., Harris,M.A., Issel-Tarver,L., Kasarskis,A., Scafe,C.R., Sherlock,G., Binkley,G., Jin,H. et al. (2000) Nucleic Acids Res., 28, 77–80], YPD and WormPD [Costanzo,M.C., Hogan,J.D., Cusick,M.E., Davis,B.P., Fancher,A.M., Hodges,P.E., Kondu,P., Lengieza,C., Lew-Smith,J.E., Lingner,C. et al. (2000) Nucleic Acids Res., 28, 73–76], Unigene [Wheeler,D.L., Chappey,C., Lash,A.E., Leipe,D.D., Madden,T.L., Schuler,G.D., Tatusova,T.A. and Rapp,B.A. (2000) Nucleic Acids Res., 28, 10–14], dbEST [Boguski,M.S., Lowe,T.M. and Tolstoshev,C.M. (1993) Nature Genet., 4, 332–333] and SWISS-PROT [Bairoch,A. and Apweiler,R. (2000) Nucleic Acids Res., 28, 45–48] and can be accessed at http://genome-www.stanford.edu/microarray.

Over the past several years, Arabidopsis thaliana has gained increasing popularity as a model system for the study of plant biology. Its short life cycle, small size and large seed output make it well suited for classical genetic analysis (reviewed in Meyerowitz 1987). Mutations have been described affecting a wide range of fundamental developmental and metabolic processes (reviewed in Estelle and Somerville 1986). A genetic linkage map consisting of some 90 loci has been assembled (Koornneef 1987) and an increasing number of cloned genes are available. In addition, Arabidopsis is ideally suited for physical mapping studies since it has a very small genome (approximately 100,000 kb; Hauge and Goodman, unpub. result) and a remarkably low content of interspersed repetitive DNA (Pruitt and Meyerowitz 1986). The availability of a complete physical map of the Arabidopsis genome will greatly simplify the cloning of any gene based solely on its mutant phenotype and genetic map location. For the map to be of any utility it is necessary to align the physical map with the classical genetic linkage map via an RFLP map.

Substance abuse often begins in adolescence and is a major factor determining health outcomes for adolescents and adults; thus, it is an important focus for prevention strategies. The use of drugs, especially alcohol, can lead to chronic addiction to substances as well as contribute to a number of common chronic conditions. These conditions include cancer, cardiovascular disease, disability from accidents or violence, and unplanned pregnancy and are major causes of morbidity and mortality among adolescents and adults. As the major social unit responsible for socialization of children and stabilization of adult personalities, the family has been the target of prevention efforts. In this chapter the empirical literature on family interventions to prevent substance use in adolescents is critically reviewed, generalizations and implications for practice identified, and directions for future research projected.

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the ∼120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes ∼13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

A comparative analysis of the genomes of Drosophila melanogaster , Caenorhabditis elegans , and Saccharomyces cerevisiae —and the proteins they are predicted to encode—was undertaken in the context of cellular, developmental, and evolutionary processes. The nonredundant protein sets of flies and worms are similar in size and are only twice that of yeast, but different gene families are expanded in each genome, and the multidomain proteins and signaling pathways of the fly and worm are far more complex than those of yeast. The fly has orthologs to 177 of the 289 human disease genes examined and provides the foundation for rapid analysis of some of the basic processes involved in human disease.

Upon the completion of the Saccharomyces cerevisiae genomic sequence in 1996 [Goffeau,A. et al. (1997) Nature, 387, 5], several creative and ambitious projects have been initiated to explore the functions of gene products or gene expression on a genome-wide scale. To help researchers take advantage of these projects, the Saccharomyces Genome Database (SGD) has created two new tools, Function Junction and Expression Connection. Together, the tools form a central resource for querying multiple large-scale analysis projects for data about individual genes. Function Junction provides information from diverse projects that shed light on the role a gene product plays in the cell, while Expression Connection delivers information produced by the ever-increasing number of microarray projects. WWW access to SGD is available at genome-www.stanford.edu/Saccharomyces/.

The Saccharomyces Genome Database (SGD) stores and organizes information about the nearly 6200 genes in the yeast genome. The information is organized around the ‘locus page’ and directs users to the detailed information they seek. SGD is endeavoring to integrate the existing information about yeast genes with the large volume of data generated by functional analyses that are beginning to appear in the literature and on web sites. New features will include searches of systematic analyses and Gene Summary Paragraphs that succinctly review the literature for each gene. In addition to current information, such as gene product and phenotype descriptions, the new locus page will also describe a gene product’s cellular process, function and localization using a controlled vocabulary developed in collaboration with two other model organism databases. We describe these developments in SGD through the newly reorganized locus page. The SGD is accessible via the WWW at http://genome-www. stanford. edu/Saccharomyces/

Male urinary pheromones modulate behavioral and neuroendocrine function in mice after being detected by sensory neurons in the vomeronasal organ (VNO) neuroepithelium. We used nuclear Fos protein immunoreactivity (Fos-IR) as a marker of changes in neuronal activity to examine the processing of male pheromones throughout the VNO projection pathway to the hypothalamus. Sexually naive male and female Balb/c mice were gonadectomized and treated daily with estradiol benzoate (EB) or oil vehicle for 3 weeks. Subjects were then exposed to soiled bedding from gonadally intact Balb/c males or to clean bedding for 90 min prior to sacrifice and processing of their VNOs and forebrains for Fos-IR. Male pheromones induced similar numbers of Fos-IR cells in the VNO neuroepithelium of oil-treated male and female subjects; however, EB-treated females had significantly more Fos-IR neurons in the VNO than any other group. There was an equivalent neuronal Fos response to male odors in the mitral and granule cells of the anterior and posterior accessory olfactory bulb of males and females, regardless of hormone treatment. In central portions of the VNO projection pathway (i.e., bed nucleus of the stria terminalis, medial preoptic area) neuronal Fos responses to male pheromones were present in female but absent in male subjects, regardless of hormone treatment. In a separate experiment, mating induced neuronal Fos-IR in these brain regions at levels in gonadally intact male subjects which were equal to or greater than those seen in ovariectomized females primed with estrogen and progesterone. This suggests that neurons in the central portions of the male's VNO pathway are capable of expressing Fos. Our results suggest that sexually dimorphic central responses to pheromones exist in mice that may begin in the VNO neuroepithelium.

Four cyclic AMP-specific, rolipram-inhibited phosphodiesterases (PDE4s) have been identified in mammals; all four are homologs of dunce, a gene required for learning and memory in Drosophila. To determine the distribution of PDE4s in the mammalian brain, specific antibodies were generated against the proteins encoded by each of three dunce homologs PDE4A, PDE4B, and PDE4D in the mouse. On Western blots, these antibodies recognized multiple protein species in all brain regions studied. Immunohistochemical studies showed that both cell bodies and neuropil were well labeled in selected regions throughout the brain. Immunoreactivity for PDE4A was found predominantly in the anterior olfactory nucleus, subiculum, layer V pyramidal neurons from the cerebral cortex, and corticospinal tracts. By contrast, anti-PDE4B-labeled neurons were observed in the inferior olive, the paraventricular and supraoptic nuclei of the hypothalamus, and in the ventral striatum. Regions of neuropil containing high levels of PDE4B immunoreactivity included the cerebellar molecular layer, globus pallidus, nucleus accumbens, and substantia nigra. Anti-PDE4D antibody distinctly labeled cerebellar Purkinje cells as well as neurons in the medial habenula and thalamic nuclei. Fibers in the fasciculus retroflexus, interpeduncular nuclei, and periaqueductal gray were also stained with this antibody. These findings indicate that the distribution of PDE4s in the brain is remarkably segregated, and suggest that each of these enzymes has a unique functional role. Furthermore, the data support the notion that rolipram, the PDE4-specific inhibitor that acts as an antidepressant in humans, may mediate its behavioral effects through PDE4B, which is highly localized to neural pathways known to underlie reward and affect in mammals.

To provide information on the activity of Gly-I in prostate cancer.We performed qualitative Gly-I assay on prostate tissues.Gly-I activity between prostate cancer and noncancerous specimens differed substantially and significantly, although such activity also varied somewhat among cancer specimens.Gly-I activity is indeed higher in cancerous than in noncancerous specimens, suggesting that it may play a role in prostate cancer homeostasis and survival.

The completion of the Saccharomyces cerevisiae genome sequencing project 11 and the continued development of improved technology for large-scale genome analysis have led to tremendous growth in the amount of new yeast genetics and molecular biology data. EYcient organization, presentation, and dissemination of this information are essential if researchers are to exploit this knowledge. In addition, the development of tools that provide eYcient analysis of this information and link it with pertinent information from other systems is becoming increasingly important at a time when the complete genome sequences of other organisms are becoming available. The aim of this review is to familiarize biologists with the type of data resources currently available on the World Wide Web (WWW). ? 1998 John Wiley & Sons, Ltd.

Comparative analysis of predicted protein sequences encoded by the genomes of Caenorhabditis elegans and Saccharomyces cerevisiae suggests that most of the core biological functions are carried out by orthologous proteins (proteins of different species that can be traced back to a common ancestor) that occur in comparable numbers. The specialized processes of signal transduction and regulatory control that are unique to the multicellular worm appear to use novel proteins, many of which re-use conserved domains. Major expansion of the number of some of these domains seen in the worm may have contributed to the advent of multicellularity. The proteins conserved in yeast and worm are likely to have orthologs throughout eukaryotes; in contrast, the proteins unique to the worm may well define metazoans.

A household contact substudy was performed as part of a prospective, cohort pertussis vaccine efficacy trial in Germany.Infants received four doses of either the Lederle/Takeda acellular pertussis component diphtheria-tetanus toxoids (DTP) vaccine (DTaP) or Lederle whole-cell component DTP vaccine at 3, 4.5, 6, and 15 to 18 months of age (Wyeth-Lederle Vaccines and Pediatrics, Pearl River, NY). An open control group received three doses of diphtheria and tetanus toxoids vaccine (DT) at 3, 4.5, and 15 to 18 months of age. Vaccine efficacy rates were calculated using a number of principal and ancillary case definitions for primary, secondary, and noncases by analyzing secondary attack rates in study infants after exposure to pertussis in the household using 7- to 28- and 7- to 42-day postexposure observation periods and the inclusion and the exclusion of noncases who received macrolide antibiotics or trimethoprim-sulfamethoxazole during the exposure period.During a 3.5-year study period, 10271 infants (DTP or DTaP, n = 8532; DT, n = 1739) were enrolled and actively followed along with all household members for cough illnesses. Depending on the case definition, 160 to 519 household exposures to pertussis were identified. In general, secondary attack rates in DT recipients were low and this was primarily because of the frequent use of antimicrobial prophylaxis. Using the principal case definitions and the exclusion of noncases who received macrolide antibiotics or trimethoprim-sulfamethoxazole during the exposure period and the 7- to 42-day observation period, the efficacy of DTP against cough illness of greater than or equal to 7 days duration caused by Bordetella pertussis was 84% (95% confidence interval [CI] = 65-93) and that of DTaP was 58% (95% CI = 30-75). Using similar criteria, the efficacy against typical pertussis (greater than or equal to 21 days of cough with either paroxysms, whoop, or posttussive vomiting) was 94% (95% CI = 77-99) and 86% (95% CI = 62-95) for DTP and DTaP, respectively. The efficacy against any cough illness (with or without) laboratory confirmation was 54% (95% CI = 32-69) and 38% (95% CI = 13-56) for DTP and DTaP, respectively.This household contact substudy within our cohort study, with active investigator-generated surveillance, was a severe test of vaccine efficacy. Both vaccines (DTP and DTaP) are better at preventing typical pertussis than mild illness. When case definitions similar to those in other recent trials are used, the Lederle/Takeda vaccine has an efficacy similar to other multicomponent DTaP vaccines.

The Saccharomyces Genome Database (SGD) provides Internet access to the complete Saccharomyces cerevisiae genomic sequence, its genes and their products, the phenotypes of its mutants, and the literature supporting these data. The amount of information and the number of features provided by SGD have increased greatly following the release of the S.cerevisiae genomic sequence, which is currently the only complete sequence of a eukaryotic genome. SGD aids researchers by providing not only basic information, but also tools such as sequence similarity searching that lead to detailed information about features of the genome and relationships between genes. SGD presents information using a variety of user-friendly, dynamically created graphical displays illustrating physical, genetic and sequence feature maps. SGD can be accessed via the World Wide Web at http://genome-www.stanford.edu/Saccharomyces/

OBJECTIVES: This study examined whether there is a risk that tetanus-toxoid-containing vaccines could cause Guillain-Barré syndrome and, if so, how large the risk is. METHODS: This study was based on previous active surveillance epidemiological studies of Guillain-Barré syndrome and vaccination history. RESULTS: A background rate of 0.3 cases of Guillain-Barré syndrome per million person-weeks has been estimated. By chance, 2.2 people with the syndrome would have received tetanus-toxoid-containing vaccine within the 6 weeks before onset, yet only 1 person had done so. Data on children show similar results. CONCLUSIONS: If an association exists, it must be extremely rare and not of public health significance.

In six of the seven efficacy studies, cases of pertussis in adults were diagnosed. In particular, primary cases in adults were common in study families in the Mainz and Erlangen studies. Recent epidemiological studies indicate that B. pertussis infections in adults are common and endemic. It is suggested that B. pertussis circulation cannot be controlled by immunization of children but that acellular vaccines make it possible to give booster immunizations to adults. An adult booster programme might decrease the circulation of B. pertussis in adults and could lead to the elimination of the organism from the population.

Bordetella pertussis is the only bacteria] species which is known to produce pertussis toxin (PT); however, both Bordetella bronchiseptica and Bordetella parapertussis contain regions homologous to the ptx genes of B. pertussis that encode the toxin subunits. After finding that several children with B. parapertussis infections exhibited modest antibody titers to PT, we examined the ptx genes of both B. parapertussis and B. bronchiseptica to determine whether they would encode stable, functional proteins even though their promoters are thought to be inactive under the conditions that have been examined. We inserted a functional promoter directly upstream of the ptx-ptl region of both species and examined culture supernatants of the resulting strains for PT activity. Biologically active PT was found in the culture supernatants of both engineered species. The toxin encoded by the B. parapertussis ptx genes appeared more labile in culture supernatants than did toxin produced by either B. pertussis or the engineered strain of B. bronchiseptica. This lability might be due to the lack of a full-length S2 subunit. We also investigated the ptl genes of these species, which are necessary for the secretion of this toxin, and found that both B. bronchiseptica and B. parapertussis contain at least certain of these genes, including ptlE and ptlF. Moreover, B. bronchiseptica appeared to contain all essential ptl genes since the introduction of a functional promoter directly upstream of the ptx-ptl region resulted in both production and efficient secretion of toxin. These results indicate that despite a number of amino acid changes in the sequences of the toxins, the toxins encoded by B. bronchiseptica and B. parapertussis are active.

The most up to date consensus from global climate models predicts warming in the Northern Hemisphere (NH) high latitudes to middle latitudes during boreal winter. However, recent trends in observed NH winter surface temperatures diverge from these projections. For the last two decades, large-scale cooling trends have existed instead across large stretches of eastern North America and northern Eurasia. We argue that this unforeseen trend is probably not due to internal variability alone. Instead, evidence suggests that summer and autumn warming trends are concurrent with increases in high-latitude moisture and an increase in Eurasian snow cover, which dynamically induces large-scale wintertime cooling. Understanding this counterintuitive response to radiative warming of the climate system has the potential for improving climate predictions at seasonal and longer timescales.

The purposes of this study were to investigate the effects of maternal employment, maternal employment attitude/behavior consistency, and degree of choice and satisfaction with the employment decision on family functioning and preterm infant development and to describe changes in family functioning over time. Data were collected in the family’s home (N = 79) when the infant was 3, 9, and 18 months old. Parents in nonemployed-mother families were more satisfied with their families at 18 months than parents in employed-mother families. Decreases in family cohesion and/or adaptability from 9 to 18 months were seen for fathers in employed-mother families, for mothers in nonemployed-mother families, and for mothers in families where the mother’s employment attitudes and behaviors were consistent. Degree of choice was positively related to the child’s mental development, mother’s perception of family cohesion, and mother’s and father’s satisfaction with family.

Cytomegalovirus (CMV) isolates from 234 asymptomatic human immunodeficiency type 1 (HIV-1)-positive men were analyzed for molecular relatedness using junctional hybridization. Of isolates shed simultaneously at two or more body sites, 36% from 22 men were different. Of 180 isolates collected from 67 men over 15 months, different strains were isolated serially from 27 men (40%), most from semen. After follow-up of 58 months (mean), the relative hazard of HIV infection progressing to AIDS was 1.8 (95% confidence interval [CI], 0.9-3.7) for men shedding the same strain of CMV and 3.0 (95% CI, 1.4-6.1) for men shedding different strains compared with men not shedding CMV in semen. The prevalence of CMV-specific IgM was higher in men shedding different versus same CMV strains (32% vs. 18%; P = .244). Thus, presence of multiple CMV strains in HIV-1-positive homosexual men is associated with progression to AIDS, possibly via activation of HIV-1-infected CD4 cells.

Pertussis is an illness that is frequently unrecognized in adults. The source of pertussis infection in young infants is usually an adult and most frequently a parent.A woman developed severe paroxysmal coughing requiring hospitalization 6 days before delivery. She was thought to have viral pneumonia and reactive airway disease. One week after birth, her infant developed a similar illness and also required hospitalization. The infant's respiratory illness progressively worsened, resulting in death.Although the clinical findings were typical for pertussis in both the mother and infant, pertussis was not considered and therefore neither received specific antimicrobial therapy. Patients with illnesses suggestive of pertussis, and their contacts, should be treated with erythromycin before the results of laboratory studies are known, in order to prevent serious and fatal illnesses in infants.

The pathophysiology of severe reactions to diphtheria-tetanus-pertussis (DTP)vaccine is not well understood. Active pertussis toxin in DTP vaccine has been proposed to cause severe DTP vaccine reactions. Large doses of pertussis toxin cause hyperinsulinemia and hypoglycemia as well as leukocytosis with a predominant lymphocytosis in animal models. To learn more about the causes of and risk factors for severe DTP vaccine reactions, children experiencing severe DTP vaccine reactions were studied.Prospective, referral-based surveillance.Los Angeles, CA.Children experiencing severe reactions within 48 hours of DTP immunization and evaluated within 24 hours of the reaction. Severe reactions included encephalopathy, persistent cryingor = 3 hours, hypotonic-hyporesponsive episodes (collapse episodes), feveror = 40.5 degrees C, or seizures. Some comparisons were made between children with DTP vaccine-associated seizures and a comparison group of children experiencing febrile seizures unrelated to immunization.A history and physical examination were performed. Follow-up examinations were performed 1 month later. Blood was collected for complete blood cell count with leukocyte differential count, serum chemistry measurements, and insulin and glucose values. Serum was assayed for active pertussis toxin, both in free and immune-complex masked states.Sixty children experienced severe reactions within 48 hours of DTP immunization: 32 children had seizures only, 14 subjects had hypotonic-hyporesponsive episodes, 2 subjects had feveror = 40.5 degrees C only, 4 subjects had persistent cryingor = 3 hours, 6 children had seizures and feveror = 40.5 degrees C, and 2 children had persistent crying and seizures. The children with seizures had a high rate of personal and family histories of seizures, and 90% had documented fevers (or = 38 degrees C). Persistent crying was associated with painful local reactions. Effects that may have been due to vaccine pertussis toxin were not found. Lymphocytosis did not occur, nor did hypoglycemia. Some relatively elevated insulin values were noted; however, this finding was also noted in the comparison group of children experiencing febrile seizures unrelated to immunization. No biologically active pertussis toxin was found in the acute sera of children experiencing severe DTP vaccine reactions.Seizures associated with DTP vaccine have similar clinical characteristics as febrile seizures, and persistent crying is initiated by painful local reactions. Vaccine endotoxin is a cause of febrile DTP vaccine reactions. We found no evidence that DTP vaccine pertussis toxin plays a role in severe DTP vaccine reactions.

Rapid cycle DNA amplification is a polymerase chain reaction technique with improved product specificity and cycle times of 20-60 s, allowing complete 30-cycle reactions in 10-30 min. The presence or absence of the delta F508 deletion and wild-type allele was determined in 104 cystic fibrosis patients by rapid cycle DNA amplification. In separate allele-specific assays, sequences on both sides of the delta F508 locus were amplified with the 3' end of a discriminating primer at the delta F508 locus, with either a 3-bp or a 1-bp mismatch. With rapid cycling (35-s cycles), single-base discrimination was achieved over a broad range of annealing temperatures (50 degrees C or lower); with conventional cycling and "hot starts" (160-s cycles), only annealing temperatures of 61-62 degrees C sufficiently discriminated between alleles. With rapid cycling, genotype could still be assessed with annealing temperatures as low as 25 degrees C. We conclude that faster temperature cycling can improve the results of allele-specific amplification.

To investigate the relationship between cytomegalovirus (CMV) infection and progression of HIV-1 disease, a group of 234 asymptomatic, HIV-1 antibody-positive homosexual men were examined for CMV isolation and levels of CMV IgM antibodies, CMV IgG antibodies, and CD4+ and CD8+ T-lymphocytes. CMV IgG antibodies were present in 100% and CMV IgM antibodies in 22% of the men. CMV was isolated from the semen of 45% of the men. No relationship was observed between CMV IgM antibodies and CMV in semen or CD4+ levels. CD4+ cell levels were significantly lower in those from whose semen CMV was isolated. In addition, an inverse relationship was observed between the concentration of CMV in semen and CD4+ levels. We postulate that the seminal tract may be a reservoir for systemic CMV infection in HIV-infected homosexual men. Reinfection from this or other sources may result in recurrent stimulation of HIV-1 replication and lead to a further decline in CD4+ cells. Clarification of whether persistent CMV infection is secondary to HIV-1-induced immunodeficiency or, conversely, promotes a more rapid decline in immunocompetency will require follow-up studies.

Summary We have assembled an integrated genetic/restriction fragment length polymorphism (RFLP) linkage map of the nuclear genome of the flowering plant Arabidopsis thaliana. The map is based on two independent sets of RFLP data, RFLP data for 123 new markers, and pair-wise segregation data of 125 classical genetic markers. Mathematical integration of the independent data sets was performed using the join map computer package. Sixty-two markers common to two or more data sets were exploited to facilitate integration of the individual maps. The current map, which encompasses a total genetic distance of 520 cM, contains 125 classical genetic markers and 306 RFLP markers. Comparison of the integrated consensus map with the individual maps demonstrates that the overall linear order of the integrated map is in good agreement with the component maps. It must be emphasized, however, that the integrated map represents the ‘best fit’ which is clearly subject to the statistical limitations of the available data. We present several examples where local differences in map order are observed between the integrated and component maps. It is likely, given the problems associated with statistical integration of mapping data from different populations, that the integrated map will contain additional local inconsistencies and problematic regions. None the less, the unified map provides a framework for building an increasingly accurate and useful map. Subsequent refinements of the map will be available electronically and researchers are invited to submit revised map data to the corresponding author for inclusion in future updates (see Appendix 1).

Bordetella pertussis produces a protein virulence factor termed pertussis toxin. Many candidate pertussis vaccines are based on the rationale that an immune response that neutralizes the virulence activities of this toxin, which are thought to arise from its catalytic ADP-ribosyltransferase activity, would be beneficial. The report describes two methods that quantify the inhibition of this activity by human serum. One, termed a direct assay, involves an initial incubation of toxin with serum, a second incubation that activates the toxin, and a third incubation that measures the ADP-ribosyltransferase activity of the mixture. The other assay, termed a plate assay, involves immobilization of the toxin, exposure of the immobilized toxin to serum and washing of the plate, and then activation and assay of the toxin's ADP-ribosyltransferase activity. The plate assay may be more selective than the direct assay in terms of identifying antibodies that neutralize the toxin in vivo. Sera from controls, selected patients presenting with cough, and vaccinated infants were first analyzed by the direct assay. In contrast to sera from controls, sera from several of the patients and vaccinated infants strongly inhibited activity. Dose-response curves of inhibition were determined for samples from three vaccinated infants by both the direct and plate assays. One of the samples had a dose-response curve of a different shape and thus differed not only in titer but also in functional characteristics. A comparison of inhibition of ADP-ribosyltransferase activity and neutralization in a CHO cell assay indicated that there was incomplete agreement between the two assays. Taken together, these results indicate that measurement of inhibition of ADP-ribosyltransferase activity by human serum is practical and may be useful in the evaluation of responses to pertussis vaccines.

Fourteen cases of patent ductus arteriosus operated upon without a fatality have been presented. All were treated by ligation and division of the ductus. The importance of the safety factor provided by the Potts-Smith-Gibson clamp has been discussed. A detailed case report of one patient whose operation was complicated by excessive hemorrhage is given in detail. No cerebral or renal damage followed a prolonged period of cardiac massage and only slight permanent cord damage resulted from complete occlusion of the aorta for over 1 hour.

The purpose of this study was to investigate the effects of maternal employment status and the mother’s degree of choice and satisfaction regarding her employment status on family functioning and, on the preterm infant’s development at three months chronologic age. Families with preterm infants (N = 110) were categorized as employed, nonemployed, and on leave of absence based on the mother’s employment status at three months postpartum. There were no significant differences across employment groups on family functioning and child development. The infant’s motor development was positively correlated with number of hours employed per week and degree of choice for the employed, mother families, but negatively correlated with choice for the nonemployed mother families. These results suggest that maternal employment may not be detrimental for infants born prior to term. Indeed, it may be beneficial, especially if the mother has a choice in the matter.

A two-part study was carried out in Alaskan Native children to evaluate the potential risk of invasive bacterial disease and the occurrence of minor illnesses after immunization with diphtheria and tetanus toxoids and whole-cell pertussis vaccine (DTP). First, a case-control comparison was performed with 186 children who had invasive Haemophilus influenzae type b or Streptococcus pneumoniae disease (cases) and 186 healthy controls matched for sex, region of residence, birth date, and number of DTP immunizations. The proportion of cases and controls immunized in the 30-day period before onset of disease for cases or reference date for controls was identical, suggesting no association with DTP immunization. In a second analysis, the occurrence of any illness, particularly infectious diseases, in 104 study subjects was compared for the period 30 days before and after 377 DTP immunizations. The rate of illness before immunization was 53%, and after immunization, 43%, again suggesting no causative effects from DTP immunization. Despite the high rates of invasive bacterial disease and nearly compete DTP immunization status in this population, no consistent relationship could be demonstrated between DTP immunization and susceptibility to infectious diseases.

To investigate the possibility that there might be an increased risk of heterologous invasive bacterial disease after routine childhood immunization with measles, mumps, and rubella vaccine live; diphtheria and tetanus toxoids and pertussis vaccine; and oral poliovirus vaccine live, a case-control study was conducted within the Kaiser Permanente Northern California pediatric population. Contrary to the premise, an apparent protective effect against invasive bacterial disease was detected after all childhood vaccinations. However, when adjustment was made for frequency of well-care visits and day-care attendance, no significant relationship was seen between receipt of routine childhood immunizations and risk of invasive heterologous bacterial disease for any individual vaccine, although a statistically significant protective effect was detected within 1 or 3 months after the receipt of any vaccine. Since a decreased risk of invasive bacterial disease was also noted to be related to the receipt of routine well-child pediatric care, other preventive health care measures may be responsible for the apparent immunization protective effect.

During the 30 years since its initial isolation, a great body of information has accumulated concerning the structure of phytochrome, the physiological responses it controls, and the genes whose expression it affects, yet little is known about the molecular mechanisms of phytochrome action. The recent advent of technologies allowing the expression of heterologous phytochrome genes in transgenic plants provide an important new method for research into the mechanisms of phytochrome action (Keller et al., 1989; Boylan and Quail, 1989; Kay et al., 1989). In the first report of this approach, Keller et al. (1989) described the expression of a functional oat phytochrome in tobacco. Transgenic plants expressing the oat protein have a radically altered phenotype characterized by decreased stem elongation, increased leaf chlorophyll content, reduced apical dominance, and delayed leaf senescence. Exploiting this “light-exaggerated” phenotype as an assay, it is now possible to identify and examine domains involved in phytochrome structure and function by in vitro mutagenesis.

The results of the following studies are reported: a longitudinal double blind trial comparing Lederle-Takeda APDT vaccine with Lederle DTP vaccine in two, four and six month old infants; two double blind similar APDT vs DTP trials in 18 month old and four to six year old children; a large longitudinal open trial with APDT in two, four and six month old infants and a household contact efficacy trial with Takeda APDT in Japan. APDT vaccine recipients had a lesser frequency and less severe reactions than whole cell vaccine recipients. Antibody responses to lymphocytosis-promoting factor and agglutinogens were higher in DTP recipients; APDT recipients had a better serologic response to filamentous hemagglutinin. Equivalent 69K protein antibody responses were seen. Vaccine efficacy in the household contact study was 98% (95% CI = 84% to 99%) against classical pertussis and 81% (95 CI = 64% to 90%) if all respiratory illnesses are considered.

Genetic and physical maps for the 16 chromosomes of Saccharomyces cerevisiae are presented. The genetic map is the result of 40 years of genetic analysis. The physical map was produced from the results of an international systematic sequencing effort. The data for the maps are accessible electronically from the Saccharomyces Genome Database (SGD: http://genome-www.stanford.edu/Saccharomyces/).

The Saccharomyces cerevisiae gene (THR1) encoding homoserine kinase (HK; EC 2.7.1.39) was cloned by complementation in yeast. Disruption of the THR1 gene results in threonine auxotrophy in yeast. Comparison of the amino acid sequences of yeast and bacterial HKs reveals substantial similarity.

We have constructed all single base substitutions in almost all of the highly conserved residues of the Tetrahymena self-splicing intron. Mutation of highly conserved residues almost invariably leads to loss of enzymatic activity. In many cases, activity could be regained by making additional mutations that restored predicted base-pairings; these second site suppressors in general confirm the secondary structure derived from phylogenetic data. At several positions, our suppression data can be most readily explained by assuming non-Watson-Crick base-pairings. In addition to the requirements imposed by the secondary structure, the sequence of the intron is constrained by "negative interactions", the exclusion of particular nucleotide sequences that would form undesirable secondary structures. A comparison of genetic and phylogenetic data suggests sites that may be involved in tertiary structural interactions.

A high-temperature superconducting magnet system for investigations of physical properties of bulk, powder, and thin-film samples is presented. This system provides a capability for a commercial vibrating-sample magnetometer, as well as thermal and electric characterization techniques to be employed in an environment with reduced refrigeration demands. These measurements can be performed over a wide range of temperatures down to 77K and in applied magnetic fields to 1T. In this report, we outline important elements of the cryogenic design, as well as measurements of the magnetic properties of a high-quality CoMn ferromagnetic thin film.

The SGS1 gene of yeast encodes a DNA helicase with homology to the human WRN gene. Mutations in WRN result in Werner's syndrome, a disease with symptoms resembling premature aging. Mutation of SGS1 is shown to cause premature aging in yeast mother cells on the basis of a shortened life-span and the aging-induced phenotypes of sterility and redistribution of the Sir3 silencing protein from telomeres to the nucleolus. Further, in old sgs1 cells the nucleolus is enlarged and fragmented-changes that also occur in old wild-type cells. These findings suggest a conserved mechanism of cellular aging that may be related to nucleolar structure.

Positional cloning has already produced the sequences of more than 70 human genes associated with specific diseases. In addition to their medical importance, these genes are of interest as a set of human genes isolated solely on the basis of the phenotypic effect of the respective mutations. We analyzed the protein sequences encoded by the positionally cloned disease genes using an iterative strategy combining several sensitive computer methods. Comparisons to complete sequence databases and to separate databases of nematode, yeast, and bacterial proteins showed that for most of the disease gene products, statistically significant sequence similarities are detectable in each of the model organisms. Only the nematode genome encodes apparent orthologs with conserved domain architecture for the majority of the disease genes. In yeast and bacterial homologs, domain organization is typically not conserved, and sequence similarity is limited to individual domains. Generally, human genes complement mutations only in orthologous yeast genes. Most of the positionally cloned genes encode large proteins with several globular and nonglobular domains, the functions of some or all of which are not known. We detected conserved domains and motifs not described previously in a number of proteins encoded by disease genes and predicted functions for some of them. These predictions include an ATP-binding domain in the product of hereditary nonpolyposis colon cancer gene (a MutL homolog), which is conserved in the HS90 family of chaperone proteins, type II DNA topoisomerases, and histidine kinases, and a nuclease domain homologous to bacterial RNase D and the 3′-5′ exonuclease domain of DNA polymerase I in the Werner syndrome gene product.