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Treatment of Giardiasis

Gardner, Timothy B.; Hill, David R.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /01/2001 Português
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Giardia lamblia is both the most common intestinal parasite in the United States and a frequent cause of diarrheal illness throughout the world. In spite of its recognition as an important human pathogen, there have been relatively few agents used in therapy. This paper discusses each class of drugs used in treatment, along with their mechanism of action, in vitro and clinical efficacy, and side effects and contraindications. Recommendations are made for the preferred treatment in different clinical situations. The greatest clinical experience is with the nitroimidazole drugs, i.e., metronidazole, tinidazole, and ornidazole, which are highly effective. A 5- to 7-day course of metronidazole can be expected to cure over 90% of individuals, and a single dose of tinidazole or ornidazole will cure a similar number. Quinacrine, which is no longer produced in the United States, has excellent efficacy but may be poorly tolerated, especially in children. Furazolidone is an effective alternative but must be administered four times a day for 7 to 10 days. Paromomycin may be used during early pregnancy, because it is not systematically absorbed, but it is not always effective. Patients who have resistant infection can usually be cured by a prolonged course of treatment with a combination of a nitroimidazole with quinacrine.

Intranasal Immunization against Dental Caries with a Streptococcus mutans-Enriched Fimbrial Preparation

Fontana, Margherita; Dunipace, Ann J.; Stookey, George K.; Gregory, Richard L.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /05/1999 Português
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Streptococcus mutans has been identified as the major etiological agent of human dental caries. The first step in the initiation of infection by this pathogenic bacterium is its attachment (i.e., through bacterial surface proteins such as glucosyltransferases, P1, glucan-binding proteins, and fimbriae) to a suitable receptor. It is hypothesized that a mucosal vaccine against a combination of S. mutans surface proteins would protect against dental caries by inducing specific salivary immunoglobulin A (IgA) antibodies which may reduce bacterial pathogenesis and adhesion to the tooth surface by affecting several adhesins simultaneously. Conventional Sprague-Dawley rats, infected with S. mutans at 18 to 20 days of age, were intranasally immunized with a mixture of S. mutans surface proteins, enriched for fimbriae and conjugated with cholera toxin B subunit (CTB) plus free cholera toxin (CT) at 13, 15, 22, 29, and 36 days of age (group A). Control rats were either not immunized (group B) or immunized with adjuvant alone (CTB and CT [group C]). At the termination of the study (when rats were 46 days of age), immunized animals (group A) had significantly (P < 0.05) higher salivary IgA and serum IgG antibody responses to the mixture of surface proteins and to whole bacterial cells than did the other two groups (B and C). No significant differences were found in the average numbers of recovered S. mutans cells among groups. However...

Mouse β-Defensin 1 Is a Salt-Sensitive Antimicrobial Peptide Present in Epithelia of the Lung and Urogenital Tract

Bals, Robert; Goldman, Mitchell J.; Wilson, James M.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: text
Publicado em /03/1998 Português
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One component of host defense at mucosal surfaces appears to be epithelium-derived peptides with antimicrobial activity called defensins. Human β-defensin 1 (hBD-1) represents the first member of the β-defensin family isolated from humans and has been implicated in the pathogenesis of cystic fibrosis. We describe in this report the isolation and characterization of a murine homolog of hBD-1 called mouse β-defensin 1 (mBD-1). The predicted amino acid sequence shows the hallmark features of other known epithelial β-defensins, including the ordered array of six cysteine residues. Analysis of a genomic clone of mBD-1 revealed two exons separated by a 15-kb intron. By use of fluorescence in situ hybridization, the mBD-1 gene was localized at the proximal portion of chromosome 8, the site where mouse α-defensins are found. Lysates from cells transfected with the mBD-1 cDNA showed antibacterial activity against gram-positive and gram-negative bacteria. mBD-1 transcripts were found in kidney, liver, and female reproductive organ tissues. In the airways, mBD-1 is expressed diffusely throughout the epithelial cells of the large proximal airways with less expression in the small distal airways and no expression in alveolar cells. The present study demonstrates that a β-defensin potentially homologous to human β-defensin 1 is present in the respiratory system and other mucosal surfaces in mice.

Impact of netilmicin regimens on the activities of ceftazidime-netilmicin combinations against Pseudomonas aeruginosa in an in vitro pharmacokinetic model.

Blaser, J; Stone, B B; Groner, M C; Zinner, S H
Tipo: text
Publicado em /07/1985 Português
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The antibacterial activities of ceftazidime and netilmicin were studied in a two-compartment in vitro model. Pseudomonas aeruginosa cultures were exposed to changing drug concentrations that mimic human pharmacokinetics. Netilmicin alone reduced the numbers of organisms in cultures of the susceptible strains by more than 99% within 4 h; however, regrowth occurred after 8 h. Although ceftazidime alone killed more slowly than netilmicin, only one of the five strains regrew within 28 h. When both drugs were combined, rapid initial killing occurred without subsequent regrowth. Studied after 24 h in combination with ceftazidime, netilmicin was as effective when given as a single daily dose as when administered in three daily doses that provided 50% more aminoglycoside per day. Decreased bacterial susceptibility was seen after ceftazidime exposure for one strain and after netilmicin exposure for all originally netilmicin-susceptible strains. No such reduction in susceptibility was observed during exposure to the combination. The results of standard in vitro checkerboard tests for synergism were predictive of the initial (4 to 8 h) but not the final (24 to 28 h) assessment of drug interaction in the pharmacokinetic model.

Nucleotide sequence of the gene encoding the vanadate-sensitive membrane-associated ATPase of Methanococcus voltae.

Dharmavaram, R; Gillevet, P; Konisky, J
Tipo: text
Publicado em /03/1991 Português
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Methanococcus voltae contains a membrane-associated ATPase whose structural gene has been sequenced. The gene encodes 565 amino acids and includes a 12-amino-acid N-terminal sequence which is not present in the purified enzyme. On the basis of its amino acid sequence, the M. voltae enzyme is unrelated to previously characterized ATPases.

Localization of the receptor gene for type D simian retroviruses on human chromosome 19.

Sommerfelt, M A; Williams, B P; McKnight, A; Goodfellow, P N; Weiss, R A
Tipo: text
Publicado em /12/1990 Português
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Simian retrovirus (SRV) serotypes 1 to 5 are exogenous type D viruses causing immune suppression in macaque monkeys. These viruses exhibit receptor interference with each other, with two endogenous type D viruses of the langur (PO-1-Lu) and squirrel monkey, and with two type C retroviruses, feline endogenous virus (RD114/CCC) and baboon endogenous virus (BaEV), indicating that each utilizes the same cell surface receptor (M. A. Sommerfelt and R. A. Weiss, Virology 176:58-69, 1990). Vesicular stomatitis virus pseudotype particles bearing envelope glycoproteins of RD114, BaEV, and the seven SRV strains were employed to detect receptors expressed in human-rodent somatic cell hybrids segregating human chromosomes. The only human chromosome common to all the susceptible hybrids was chromosome 19. By using hybrids retaining different fragments of chromosome 19, a provisional subchromosomal localization of the receptor gene was made to 19q13.1-13.2. Antibodies previously reported to be specific to a BaEV receptor (L. Thiry, J. Cogniaux-Leclerc, R. Olislager, S. Sprecher-Goldberger, and P. Burkens, J. Virol. 48:697-708, 1983) did not block BaEV, RD114, or SRV pseudotypes or syncytia. Antibodies to known surface markers determined by genes mapped to chromosome 19 did not block virus-receptor interaction. The identity of the receptor remains to be determined.

Renal Tubular Transport of proline, Hydroxyproline, and Glycine. III. GENETIC BASIS FOR MORE THAN ONE MODE OF TRANSPORT IN HUMAN KIDNEY

Tipo: text
Publicado em /05/1968 Português
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Unique sequence organization and erythroid cell-specific nuclear factor-binding of mammalian theta 1 globin promoters.

Kim, J H; Yu, C Y; Bailey, A; Hardison, R; Shen, C K
Tipo: text
Publicado em 25/07/1989 Português
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The theta 1 globin gene is an alpha globin-like gene, and started to diverge from the other members of the alpha globin family 260 million years ago. DNA sequencing and transcriptional analysis indicated that it is functional in erythroid cells of the higher primates, but not in prosimians and rabbit. The theta 1 promoter region of higher primates including man consists of GC-rich sequences characteristic of housekeeping gene promoters, and CCAAT and TATA boxes located further upstream. It is shown here that the housekeeping gene promoter-like region of human theta 1 contains two tandemly arranged, GC-rich motifs (GC-I and GC-II). Of these, GC-II interacts with nuclear factor(s) present in the globin-expressing, erythroleukemia cell line K562, before and after hemin induction. GC-I, however, interacts with nuclear factor(s) only present in hemin-induced K562 cells. These factors are different from previously reported erythroid cell-specific factors, and are not detectable in non-erythroid Hela cells. Furthermore, the sequence of the motif GC-I and its location relative to ATG codon have been conserved among all known mammalian theta 1 globin genes. Finally, and most interestingly, the CCAAT box of theta 1 is contained within a 38 bp internal segment of Alu repeat sequence. Immediately upstream from this CCAAT box-containing Alu repeat segment is a 241 bp Alu repeat pointing in the opposite direction. The conservation of this novel arrangement among the higher primates suggests that an inserted Alu family repeat and its flanking genomic sequence have co-evolved...

Scleral melting and conjunctival rhinosporidiosis

Sunderraj, P
Tipo: text
Publicado em /03/1992 Português
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Correlation between Phenylalanine Ammonia Lyase Activity and Phenolic Biosynthesis in p-Fluorophenylalanine-sensitive and -resistant Tobacco and Carrot Tissue Cultures 1

Berlin, Jochen; Widholm, Jack M.
Tipo: text
Publicado em /04/1977 Português
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Phenylalanine ammonia lyase (PAL) activity was measured in p-fluorophenylalanine (PFP)-sensitive and -resistant tobacco (Nicotiana tabacum L.) and carrot (Daucus carota L.) cell lines which are known to oversynthesize phenylalanine. A correlation between phenolic levels and PAL activities was detected. The phenylalanine analog-resistant and -sensitive carrot cells showed no differences in the accumulation of phenolic compounds and PAL activities. The PFP-resistant tobacco cells, however, had 10 times higher levels of phenolics and also 10 to 20 times higher PAL activities than the PFP-sensitive line. The PAL activity in the resistant tobacco line increased dramatically after inoculation of the cells into fresh medium. Conditions affecting this increase were characterized.

The Archaeology of the Southwest: A Preliminary Report

Nelson, N. C.
Tipo: text
Publicado em /04/1919 Português
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Diagnosing myocardial infarction : Randomised controlled trial and economic evaluation of a chest pain unit are in progress

Goodacre, Steve; Morris, Francis; Campbell, Stephen; Quinney, Deborah; Capewell, Simon
Fonte: BMJ Group Publicador: BMJ Group
Tipo: text
Publicado em 08/12/2001 Português
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In brief

Fonte: BMJ Publicador: BMJ
Tipo: text
Publicado em 16/02/2002 Português
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Mitochondrial adenosine triphosphatase of the fission yeast, Schizosaccharomyces pombe 972h-. Changes in activity and oligomycin-sensitivity during the cell cycle of catabolite-repressed and -de-repressed cells.

Edwards, S W; Lloyd, D
Tipo: text
Publicado em 15/01/1977 Português
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1. Changes in activity of ATPase (adenosine triphosphatase) during the cell cycle of Schizosaccharomyces pombe were analysed in cell-free extracts of cells harvested from different stages of growth of synchronous cultures and also after cell-cycle fractionation. 2. Oligomycin-sensitive ATPase oscillates in both glucose-repressed synchronous cultures and shows four maxima of activity approximately equally spaced through the cell cycle. The amplitude of the oscillations accounts for between 13 and 80% of the total activity at different times in the cell cycle. 3. Oligomycin sensitivity varies over a fourfold range at different stages of the cell cycle. 4. The periodicity of maximum oligomycin sensitivity is one-quarter of a cell cycle. 5. These results were confirmed for the first three-quarters of the cell cycle by cell-cycle fractionation. 6. In cells growing synchronously with glycerol, ATPase activity increases in a stepwise pattern, with two steps per cell cycle; the first of these occurs at 0.54 of the cell cycle and the second at 0.95. 7. These results are discussed in relation to previously obtained data on the development of mitochondrial activities during the cell cycle.

Chair discussions

Peters, W
Tipo: text
Publicado em //1989 Português
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Analysis of Binding Reactions by Fluorescence Recovery after Photobleaching

Sprague, Brian L.; Pego, Robert L.; Stavreva, Diana A.; McNally, James G.
Fonte: Biophysical Society Publicador: Biophysical Society
Tipo: text
Publicado em /06/2004 Português
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Fluorescence recovery after photobleaching (FRAP) is now widely used to investigate binding interactions in live cells. Although various idealized solutions have been identified for the reaction-diffusion equations that govern FRAP, there has been no comprehensive analysis or systematic approach to serve as a guide for extracting binding information from an arbitrary FRAP curve. Here we present a complete solution to the FRAP reaction-diffusion equations for either single or multiple independent binding interactions, and then relate our solution to the various idealized cases. This yields a coherent approach to extract binding information from FRAP data which we have applied to the question of transcription factor mobility in the nucleus. We show that within the nucleus, the glucocorticoid receptor is transiently bound to a single state, with each molecule binding on average 65 sites per second. This rapid sampling is likely to be important in finding a specific promoter target sequence. Further we show that this predominant binding state is not the nuclear matrix, as some studies have suggested. We illustrate how our analysis provides several self-consistency checks on a FRAP fit. We also define constraints on what can be estimated from FRAP data...

Craniometry of some of the Outcaste Tribes of the Panjab

Charles, R. Havelock
Tipo: text
Publicado em /10/1891 Português
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Typing of Staphylococcus aureus resistant to methicillin.

French, G L; Ling, J; Farrington, M; Ng, E
Tipo: text
Publicado em 29/11/1986 Português
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Modification of the cerebrovascular response to noradrenaline by bile duct ligation.

Bloom, D S; Eidelman, B H; McCalden, T A
Tipo: text
Publicado em /09/1975 Português
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The effects of intracarotid infusions of noradrenaline on the cerebral vasculature were studied in seven baboons with bile duct ligation. Infusion of 8 mug and 16 mug/min of noradrenaline resulted in a significant decrease in cerebral blood flow in the jaundiced animals. In normal baboons, these doses produced cerebrovascular dilatation. These results indicate that there is an increased cerebrovascular sensitivity to noradrenaline in the obstructive jaundice which follows bile duct ligation. It is postulated that noradrenaline smooth muscle uptake mechanisms are disturbed allowing a greater concentration of the amine at the receptor sites.

KANNUS RESPONDS

Kannus, Pekka
Fonte: © American Journal of Public Health 2005 Publicador: © American Journal of Public Health 2005
Tipo: text
Publicado em /08/2005 Português
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