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31.
32.
Simone A. French Cheryl L. Perry Gloria R. Leon Jayne A. Fulkerson 《Obesity (Silver Spring, Md.)》1996,4(1):27-33
Self-esteem has been hypothesized to be lower in obese adolescents relative to their normal weight peers and to be an important factor in preventing or reversing obesity. The present study examined the relationship between obesity and self-esteem cross-sectionally and prospectively over three years in a cohort of 1278 adolescents in grades 7 to 9 at baseline. Cross-sectional analyses revealed an inverse association between physical appearance self-esteem and body mass index in both males and females. In females, body mass index was inversely associated with global self-esteem, close friendship, and behavioral conduct self-esteem. In males, body mass index was inversely associated with athletic and romantic appeal self-esteem. Prospectively, in females, physical appearance and social acceptance self-esteem at baseline were inversely related to body mass index three years later. Baseline self-esteem was unrelated prospectively to change in body mass index in males. All associations were modest in magnitude. These results suggest that in a middle class white sample of adolescents, self-esteem specific to physical appearance is modestly associated with body mass index. Low self-esteem does not appear to predict the development of obesity over time. 相似文献
33.
34.
Human alveolar macrophage fibronectin: synthesis, secretion, and ultrastructural localization during gelatin-coated latex particle binding 总被引:14,自引:4,他引:10
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Human pulmonary alveolar macrophages synthesized and secreted several characteristic high molecular weight proteins for at least 7 d in vitro. Immunoprecipitates of medium and cell lysates from metabolically labeled cultures with specific anti-human plasma fibronectin IgG contained one major labeled polypeptide of molecular weight 440,000 (unreduced) or 220,000 (reduced). An identical polypeptide in conditioned medium from radiolabeled macrophages bound specifically to gelatin-Sepharose, demonstrating that alveolar macrophages synthesized and secreted a molecule immunologically and functionally similar to fibronectin. Fibronectin was the major newly synthesized and secreted polypeptide of freshly harvested alveolar macrophages. Pulse-chase experiments revealed that newly synthesized fibronectin was rapidly secreted into medium, approximately 50 percent appearing by 1 h and 80 percent by 8 h. Immunoperoxidase staining using antifibronectin F(ab’)(2)-peroxidase conjugates revealed the majority of immunoreactive fibronectin to be intracellular, localized to endoplasmic reticulum and Golgi apparatus. No extracellular matrix fibronectin was visualized, and cell surface staining was rarely seen, usually appearing only at sites where cells were closely apposed and not at sites of macrophage-substrate attachment. Similar immunostaining of fibroblast cultures revealed cell surface-associated fibrillar fibronectin. Ultrastructural localization of fibronectin during binding and phagocytosis of gelatin-coated and plain latex particles revealed fibronectin only on gelatin-latex beads and at their cell binding sites. Neigher plain latex beads nor their cell membrane binding sites stained for fibronectin. These results demonstrate that fibronectin is a major product of human alveolar macrophages, is rapidly secreted, and is localized at cell membrane binding sites for gelatin-coated particles. In view of the known binding properties of fibronectin, it may serve as an endogenous opsonic factor promoting the binding of staphylococcus, denatured collagen, fibrin, or other macromolecules to macrophages in the lower respiratory tract. 相似文献
35.
On the phospholipids of Bacillus megaterium 总被引:12,自引:0,他引:12
36.
37.
Phylogenetic screening of the human genome: identification of differentially hybridizing repetitive sequence families 总被引:1,自引:0,他引:1
The phi-screen, a method of phylogenetic screening, can be employed to
detect repetitive sequence families that differentially hybridize between
closely related species. Such differences may involve sequence divergence
or variations in copy number, including total presence versus absence of a
family of repeated DNA. We present the results of a phi-screen comparing
the human genome to that of the prosimian, Galago crassicaudatus. Three
human repetitive families that are divergent or not present in galago have
been detected. One of these families is described in detail; it is similar
among the anthropoids but is present in a lower copy number and/or
divergent form in prosimians. The family is clearly related to the
transposon-like human element (THE) described by Paulson et al. (1985).
THEs have long terminal repeats reminiscent of retroviruses but are unique
in that they have no sequence similarity to known mammalian retroviruses.
The sequence of a solo long terminal repeat, found unassociated with THE
internal sequence, is presented. This family member, THE p2, is bordered by
a 5-bp target-site repeat and is interrupted by the insertion of an Alu
element. A solo THE element sequenced by Wiginton et al. (1986) contains an
insertion of Alu at precisely the same position as does THE p2.
相似文献
38.
The alcohol dehydrogenase (Adh) region from five planitibia subgroup
species of Hawaiian picture-wing Drosophila has been cloned. A total of 15
kb of DNA in and around the Adh gene has been compared among the five
species. Genetic distances were calculated to determine evolutionary
relationships. These distances agree with previous distances determined by
protein polymorphism and DNA hybridization techniques and can be
interpreted in terms of specific island colonization and speciation
(founder) events over the past 5 Myr. Examination of the restriction maps
of the cloned Adh region from the five species shows many instances of
small deletions, insertion of a transposable element in D. heteroneura, and
the existence of a highly variable region on the 3' side of the Adh gene.
Clustering relationships and rates of DNA change are calculated and
compared with the relationship found for other species of Drosophila.
相似文献
39.
Maximillian Rosario John Fulkerson Shamit Soneji Joe Parker Eung-Jun Im Nicola Borthwick Anne Bridgeman Charles Bourne Joan Joseph Jerald C. Sadoff Tomá? Hanke 《Journal of virology》2010,84(15):7815-7821
Although major inroads into making antiretroviral therapy available in resource-poor countries have been made, there is an urgent need for an effective vaccine administered shortly after birth, which would protect infants from acquiring human immunodeficiency virus type 1 (HIV-1) through breast-feeding. Bacillus Calmette-Guérin (BCG) is given to most infants at birth, and its recombinant form could be used to prime HIV-1-specific responses for a later boost by heterologous vectors delivering the same HIV-1-derived immunogen. Here, two groups of neonate Indian rhesus macaques were immunized with either novel candidate vaccine BCG.HIVA401 or its parental strain AERAS-401, followed by two doses of recombinant modified vaccinia virus Ankara MVA.HIVA. The HIVA immunogen is derived from African clade A HIV-1. All vaccines were safe, giving local reactions consistent with the expected response at the injection site. No systemic adverse events or gross abnormality was seen at necropsy. Both AERAS-401 and BCG.HIVA401 induced high frequencies of BCG-specific IFN-γ-secreting lymphocytes that declined over 23 weeks, but the latter failed to induce detectable HIV-1-specific IFN-γ responses. MVA.HIVA elicited HIV-1-specific IFN-γ responses in all eight animals, but, except for one animal, these responses were weak. The HIV-1-specific responses induced in infants were lower compared to historic data generated by the two HIVA vaccines in adult animals but similar to other recombinant poxviruses tested in this model. This is the first time these vaccines were tested in newborn monkeys. These results inform further infant vaccine development and provide comparative data for two human infant vaccine trials of MVA.HIVA.Close to 2.3 million of children globally are infected with human immunodeficiency virus type 1 (HIV-1). The majority of neonatal infections occur in utero or intrapartum and, in the absence of preventative interventions, up to 29% of infants breast-fed by infected mothers acquire HIV-1 (6). Furthermore, HIV-1-infected children face a worse prognosis than adults in that, without antiretroviral treatment (ART), 25% of perinatally infected children progress to AIDS within 1 year (10), and the median time to AIDS for the remaining children is less than 7 years (2). It is now clearly established that maternal and extended infant ART can substantially reduce transmission of HIV-1 through breast-feeding (23). However, in a resource-poor setting, many logistical barriers to implementation of the ART-based prevention of mother-to-child-transmission (PMTCT) remain (23). Because nutrition and hygiene makes breast milk an important determinant of infant survival (22, 28), formula feeding as a protective measure against HIV-1 acquisition is recommended only if it is AFASS (acceptable, feasible, affordable, sustainable, and safe). Unfortunately, AFASS it is still not for majority of infected mothers in sub-Saharan Africa. Also, mixed bottle and breast feeding is associated with a 10-fold increase in HIV-1 transmission relative to exclusive breast-feeding (4). Thus, an effective infant vaccine against HIV-1 infection is the best and safest solution for PMTCT of HIV-1 with the added practical option of prolonging breast-feeding.Neonatal immunity is immature compared to the adult immune system (25). The differences include naivety of the immune cells, a tendency to develop Th2 responses (5) and antigen-presenting cells with inefficient cytokine production (35). For example, human cord blood T cells proliferated poorly and produced low levels of interleukin-2 (IL-2) and gamma interferon (IFN-γ) when endogenous antigen-presenting cells presented the antigen (35, 44). Also, infant myeloid dendritic cells are less efficient in priming Th1 responses because of their decreased responsiveness to Toll-like receptor stimulation, lower levels of surface costimulatory molecules, and lower production of IL-12 (8, 27). In several infections, qualitative and quantitative differences between human newborn and adult responses were detected (1, 9, 26, 37). In contrast, other studies of infants reported proliferation as well as IL-2 and IFN-γ production by T cells equal to that of adults following T-cell receptor-independent activation (21, 46). These latter observations indicate that neonate T cells are not intrinsically “locked” into an immature phenotype but, given the correct stimuli, they can develop mature immune responses (25). The requirement for specific stimuli will likely differ for different pathogens and vaccine vectors.Mycobacterium bovis bacillus Calmette-Guérin (BCG) is commonly delivered at birth as an antituberculosis vaccine as a part of the WHO Expanded Programme on Immunization (EPI). It has been reported by several studies to promote an adultlike Th1 response in newborns (16, 24, 34, 43), although it was also suggested that delaying the BCG delivery to 10 weeks of age benefits the quantity and quality of BCG-induced CD4 T-cell responses (20). BCG and related mycobacterial vectors have been explored as vaccines against other infectious agents, including human and simian immunodeficiency viruses (19), and in adult animals showed immunogenicity and protection (3, 36, 39, 47, 48). The only clinical study of recombinant BCG (rBCG) in adults failed to provide consistent efficacy (7). We have suggested the use of rBCG expressing an HIV-1-derived immunogen as the priming component of a heterologous vaccine platform for PMTCT of HIV-1 through infected breast milk (18), where it is critical to prime HIV-1-specific responses as soon as possible after birth. These responses could be boosted a few weeks later or shortly after the already busy EPI by heterologous vaccines delivering the same HIV-1-derived immunogen. To this extent, we constructed the novel candidate vaccine BCG.HIVA401 (36) by inserting a gene coding for the HIV-1 clade A-derived immunogen HIVA (14) into recombinant BCG strain AREAS-401 (40). AERAS-401 is a newly developed strain that displayed enhanced safety (40) and immunogenicity (11, 15) in murine models relative to its parental BCG vaccine strain Danish SSI-1331. Increased safety represents an important feature should the BCG.HIVA401 vaccine be deployed in babies born to HIV-1-infected mothers. We showed that BCG.HIVA401 in a heterologous combination with recombinant modified vaccinia virus Ankara MVA.HIVA and recombinant ovine atadenovirus OAdV.HIVA induced robust polyfunctional HIV-1-specific T-cell responses in adult macaques (36). Here, we assess the safety and immunogenicity of the BCG.HIVA prime-MVA.HIVA boost regimen in newborn rhesus macaques. 相似文献
40.
Wagner Vital Gustavo Lazzaro Rezende Leonardo Abreu Jorge Moraes Francisco JA Lemos Itabajara da Silva VazJr Carlos Logullo 《BMC developmental biology》2010,10(1):25