bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Murine H2-Dd- and H2-Ab-Restricted T-Cell Epitopes on a Novel Protective Antigen, MPT51, ofMycobacterium tuberculosis
Authors: Suzuki Mina , Aoshi Taiki , Nagata Toshi , Koide Yukio 
Published: June 2004

ABSTRACTBoth CD4+type 1 helper T (Th1) cells and CD8+cytotoxic T lymphocytes (CTL) play pivotal roles in protection againstMycobacterium tuberculosisinfection. Here, we identified Th1 and CTL epitopes on a novel protective antigen, MPT51, in BALB/c and C57BL/6 mice. Mice were immunized with plasmid DNA encoding MPT51 by using a gene gun, and gamma interferon (IFN-γ) production from the immune spleen cells was analyzed in response to a synthetic overlapping peptide library covering the mature MPT51 sequence. In BALB/c mice, only one peptide, p21-40, appeared to stimulate the immune splenocytes to produce IFN-γ. Flow cytometric analysis with intracellular IFN-γ and the T-cell phenotype revealed that the p21-40 peptide contains an immunodominant CD8+T-cell epitope. Further analysis with a computer-assisted algorithm permitted identification of a T-cell epitope, p24-32. In addition, a major histocompatibility complex class I stabilization assay with TAP2-deficient RMA-S cells transfected with Kd, Dd, or Ldindicated that the epitope is presented by Dd. Finally, we proved that the p24-32/Ddcomplex is recognized by IFN-γ-producing CTL. In C57BL/6 mice, we observed H2-Ab-restricted dominant and subdominant Th1 epitopes by using T-cell subset depletion analysis and three-color flow cytometry. The data obtained are useful for analyzing the role of MPT51-specific T cells in protective immunity and for designing a vaccine againstM. tuberculosisinfection.
Cleavage of Host Keratin 8 by a Chlamydia-Secreted Protease
Authors: Dong Feng , Su Heng , Huang Yanqing , Zhong Youmin , Zhong Guangming 
Published: June 2004

ABSTRACT
Chlamydiae have to replicate within a cytoplasmic vacuole in eukaryotic cells. Expansion of the chlamydia-laden vacuole is essential for chlamydial intravacuolar replication, which inevitably causes host cell cytoskeleton rearrangements. A cleavage fragment of keratin 8 corresponding to the central rod region was detected in the soluble fraction of chlamydia-infected cells. Since keratin 8 is a major component of the intermediate filaments in simple epithelial cells, cleavage of keratin 8 may increase the solubility of the host cell cytoskeleton and thus permit vacuole expansion in chlamydia-infected cells. A chlamydia-secreted protease designated CPAF (chlamydial protease/proteasome-like activity factor) was both necessary and sufficient for keratin 8 cleavage in chlamydia-infected cells, suggesting that chlamydiae have evolved specific mechanisms for modifying the host cell cytoskeleton.
The Ami-AliA/AliB Permease of
Streptococcus pneumoniae
Is Involved in Nasopharyngeal Colonization but Not in Invasive Disease
Authors: Kerr A. R. , Adrian P. V. , Estevão S. , de Groot R. , Alloing G. , Claverys J.-P. , Mitchell T. J. , Hermans P. W. M. 
Published: June 2004

ABSTRACT

The Ami-AliA/AliB oligopeptide permease is an ATP-binding cassette transporter which is found in
Streptococcus pneumoniae
and which is involved in nutrient uptake. We investigated the role of the three paralogous oligopeptide-binding lipoproteins AmiA, AliA, and AliB by using murine models of pneumococcal colonization and invasive disease. A series of mutants lacking
aliA
,
aliB
, and
amiA
either alone or in combination as double or triple mutations were used. Inoculation of the nasopharynx with a mixture of the
obl
(oligopeptide-binding lipoprotein-negative) triple-mutant and wild-type (D39) bacteria resulted in significantly smaller numbers of
obl
bacteria colonizing the nasopharynx. The use of a mixture of individual mutants and wild-type pneumococci revealed that AmiA, AliA, and AliB were all required for successful colonization of the nasopharynx. The
obl
mutant was more attenuated than the
aliB
mutant but not the
aliA
or
amiA
mutant. Therefore, there is some redundancy in the Ami-AliA/AliB complex in terms of nasopharyngeal colonization, with AliA and AmiA being able to compensate for the removal of AliB. Animals with invasive disease caused by these mutants had survival times, bacterial loads, and inflammatory cytokine production levels similar to those of animals infected with wild-type pneumococci. Our results show that although the Ami-AliA/AliB complex is not required for virulence during pneumococcal pneumonia, it does play a role in colonization of the nasopharynx.
Dual Role of Interleukin-4 (IL-4) in Pulmonary Paracoccidioidomycosis: Endogenous IL-4 Can Induce Protection or Exacerbation of Disease Depending on the Host Genetic Pattern
Authors: Arruda Celina , Valente-Ferreira Rita C. , Pina Adriana , Kashino Suely S. , Fazioli Raquel A. , Vaz Celidéia A. C. , Franco Marcello F. , Keller Alexandre C. , Calich Vera L. G. 
Published: June 2004

ABSTRACTResistance to paracoccidioidomycosis, the most important endemic mycosis in Latin America, is thought to be primarily mediated by cellular immunity and the production of gamma interferon. To assess the role of interleukin-4 (IL-4), a Th2 cytokine, pulmonary paracoccidioidomycosis in IL-4-depleted susceptible (B10.A) and intermediate (C57BL/6) mice was studied. Two different protocols were used to neutralize endogenous IL-4 in B10.A mice: 1 mg of anti-IL-4 monoclonal antibody (MAb)/week and 8 mg 1 day before intratracheal infection with 106Paracoccidioides brasiliensisyeast cells. Unexpectedly, both protocols enhanced pulmonary infection but did not alter the levels of pulmonary cytokines and specific antibodies. Since in a previous work it was verified that C57BL/6 mice genetically deficient in IL-4 were more resistant toP. brasiliensisinfection, we also investigated the effect of IL-4 depletion in this mouse strain. Treatment with the MAb at 1 mg/week led to less severe pulmonary disease associated with impaired synthesis of Th2 cytokines in the lungs and liver of control C57BL/6 mice. Conversely, in IL-4-depleted C57BL/6 mice, increased levels of tumor necrosis factor alpha and IL-12 were found in the lungs and liver, respectively. In addition, higher levels of immunoglobulin G2a (IgG2a) and lower levels of IgG1 antibodies were produced by IL-4-depleted mice than by control mice. Lung pathologic findings were equivalent in IL-4-depleted and untreated B10.A mice. In IL-4-depleted C57BL/6 mice, however, smaller and well-organized granulomas replaced the more extensive lesions that developed in untreated mice. These results clearly showed that IL-4 can have a protective or a disease-promoting effect in pulmonary paracoccidioidomycosis depending on the genetic background of the host.
A Two-Component
covRS
Regulatory System Regulates Expression of Fructosyltransferase and a Novel Extracellular Carbohydrate in
Streptococcus mutans
Authors: Lee Song F. , Delaney Gillian D. , Elkhateeb Mohammad 
Published: June 2004

ABSTRACT

The expression of fructosyltransferase (FTF), the enzyme that synthesizes fructan from sucrose, is regulated in the cariogenic bacterium
Streptococcus mutans
. However, the exact mechanism of FTF regulation is unknown. In this study, the role of a two-component regulatory system (
covRS
) in FTF expression was investigated. A CovR-defective mutant of
S. mutans
NG8 was constructed by homologous recombination. By use of immunoblotting, the mutant was shown to overexpress FTF in the absence of sucrose, while the wild type and a
covRS
-complemented mutant showed sucrose-inducible FTF expression. Reverse transcription-PCR showed that the
ftf
transcript levels were increased in the
covR
mutant, suggesting regulation at the transcriptional level. The
covR
mutant was also found to overproduce extracellular carbohydrate, and this phenotype was reversed by
covRS
complementation. Paper chromatographic studies and chemical tests showed that the extracellular carbohydrate contained glucose and glucuronic acid but not fructose. These results suggest that the extracellular carbohydrate was not fructan. The production of a glucose- and glucuronic acid-containing extracellular carbohydrate has not been reported for
S. mutans
and may be considered novel. In conclusion, the results indicate that the expression of FTF and a glucose- and glucuronic acid-containing carbohydrate was negatively regulated by the
covRS
two-component regulatory system in
S. mutans
.
The Two Murein Lipoproteins ofSalmonella entericaSerovar Typhimurium Contribute to the Virulence of the Organism
Authors: Sha J. , Fadl A. A. , Klimpel G. R. , Niesel D. W. , Popov V. L. , Chopra A. K. 
Published: June 2004

ABSTRACTSeptic shock due toSalmonellaand other gram-negative enteric pathogens is a leading cause of death worldwide. The role of lipopolysaccharide in sepsis is well studied; however, the contribution of other bacterial outer membrane components, such as Braun (murein) lipoprotein (Lpp), is not well defined. The genome ofSalmonella entericaserovar Typhimurium harbors two copies of the lipoprotein (lpp) gene. We constructed a serovar Typhimurium strain with deletions in both copies of thelppgene (lpp1andlpp2) by marker exchange mutagenesis. The integrity of the cell membrane and the secretion of the effector proteins through the type III secretion system were not affected in thelppdouble-knockout mutant. Subsequently, the virulence potential of this mutant was examined in a cell culture system using T84 intestinal epithelial and RAW264.7 macrophage cell lines and a mouse model of salmonellosis. Thelppdouble-knockout mutant was defective in invading and inducing cytotoxic effects in T84 and RAW264.7 cells, although binding of the mutant to the host cell was not affected when compared to the wild-type (WT) serovar Typhimurium. The motility of the mutant was impaired, despite the finding that the number of flagella was similar in thelppdouble knockout mutant and the WT serovar Typhimurium. Deletion in thelppgenes did not affect the intracellular survival and replication ofSalmonellain macrophages and T84 cells. Induction of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-8 (IL-8) was significantly reduced in macrophages and T84 cells infected with thelppdouble-knockout mutant. The levels of IL-8 remained unaffected in T84 cells when infected with either live or heat-killed WT andlppmutant, indicating that invasion was not required for IL-8 production and that Toll-like receptor 2 signaling might be affected in the Lpp double-knockout mutant. These effects of the Lpp protein could be restored by complementation of the isogenic mutant. Thelppdouble-knockout mutant was avirulent in mice, and animals infected with this mutant were protected from a lethal challenge dose of WT serovar Typhimurium. The severe combined immunodeficient mice, on the other hand, were susceptible to infection by thelppdouble-knockout mutant. The serovar Typhimurium mutants from which only one of thelpp(lpp1orlpp2) genes was deleted were also avirulent in mice. Taken together, our data indicated that Lpp specifically contributed to the virulence of the organism.
Chemotherapy for Schistosomiasis in Ugandan Fishermen: Treatment Can Cause a Rapid Increase in Interleukin-5 Levels in Plasma but Decreased Levels of Eosinophilia and Worm-Specific Immunoglobulin E
Authors: Fitzsimmons Colin M. , Joseph Sarah , Jones Frances M. , Reimert Claus M. , Hoffmann Karl F. , Kazibwe Francis , Kimani Gachuhi , Mwatha Joseph K. , Ouma John H. , Tukahebwa Edridah M. , Kariuki Henry. C. , Vennervald Birgitte J. , Kabatereine Narcis B. , Dunne David W. 
Published: June 2004

ABSTRACTChemotherapy for blood-dwelling schistosomes kills the worms and exposes parasite antigen to the circulation. In many people from areas of endemicity, this treatment increases parasite-specific immunoglobulin E (IgE) and other Th2 responses in the months following therapy, responses that have been associated with subsequent resistance to reinfection. Here we investigate much earlier changes in immune reactions after praziquantel therapy inSchistosoma mansoni-infected fishermen working in an area of high transmission in Uganda. The subjects gave blood before treatment and at 1 and 21 days posttreatment. Blood cultures were incubated with schistosome soluble worm antigen (SWA) or soluble egg antigen (SEA). Interleukin-4 (IL-4), IL-5, IL-10, IL-13, gamma interferon, and transforming growth factor β levels were measured in the cultures and in plasma. A marked transient increase in plasma IL-5 levels was observed in 75% of the subjects (n= 48) by 1 day posttreatment. This response was dependent on pretreatment intensity of infection and was accompanied by a transient decrease in eosinophil numbers. One day posttreatment, blood cultures from the 16 subjects with the greatest increase in plasma IL-5 level (>100 pg/ml) displayed reduced IL-5, IL-13, and IL-10 responses to SWA, and in contrast to the rest of the cohort, these high-IL-5 subjects displayed reduced levels of SWA-specific IgE in plasma 21 days posttreatment. Twenty months after treatment, the intensity of reinfection was positively correlated with the increase in plasma IL-5 level seen 1 day posttreatment. These studies describe the heterogeneity in early immune reactions to treatment, identifying subgroups who have different patterns of reaction and who may have different capacities to mount the responses that have been associated with resistance to reinfection.
Inducible Nitric Oxide Synthase Is Not Essential for Control ofTrypanosoma cruziInfection in Mice
Authors: Cummings Kara L. , Tarleton Rick L. 
Published: June 2004

ABSTRACTImmune control of many intracellular pathogens, includingTrypanosoma cruzi, is reported to be dependent on the production of nitric oxide. In this study, we show that mice deficient in inducible nitric oxide synthase (iNOS or NOS2) exhibit resistance toT. cruziinfection that is comparable to that of wild-type mice. This is the case for two iNOS-deficient mouse strains, Nos2tm1Lauand Nos2 N5, infected with the Brazil or Tulahuen strain ofT. cruzi. In all cases, blood parasitemia, tissue parasite load, and survival rates are similar between wild-type and iNOS-deficient mice. In contrast, both wild-type and Nos2tm1Laumice died within 32 days postinfection when treated with the nitric oxide synthase inhibitor aminoguanidine. Increased transcription of NOS1 or NOS3 is not found in iNOS-knockout (KO) mice, indicating that the absence of nitric oxide production through iNOS is not compensated for by increased production of other NOS isoforms. However, Nos2tm1Laumice exhibit enhanced expression of tumor necrosis factor alpha, interleukin-1, and macrophage inflammatory protein 1α compared to that of wild-type mice, and these alterations may in part compensate for the lack of iNOS. These results clearly show that iNOS is not required for control ofT. cruziinfection in mice.
Antibodies Produced in Response toCryptococcus neoformansPulmonary Infection in Mice Have Characteristics of Nonprotective Antibodies
Authors: Zaragoza Oscar , Casadevall Arturo 
Published: June 2004

ABSTRACTMurine cryptocococcal pulmonary infection elicited serum immunoglobulin M (IgM) and IgG to the capsular polysaccharide, but only IgG stained yeast cells in alveoli. Both isotypes produced punctuate immunofluorescence patterns on yeast cells like those of nonprotective antibodies. The difficulties involved in associating humoral immunity with protection in murine cryptocococcal infection could reflect nonprotective antibody responses.
On the Origins of Majālis Al-tujjār in Mid-nineteenth Century Egypt
Authors: Goldberg Jan 
Published: June 2004

AbstractSeeking to establish the origins of Majālis al-Tujjār, the special mixed commercial courts of Alexandria and Cairo which existed from the mid-1840s until the mid-1870s, I examine whether the Majālis had their origin in Turkey or in Egypt; and whether or not they served foreign interests and were part of the capitulations system. The evidence of a legal case registered in the court records (sijillāt) of the Cairo court suggests that the Majālis, though established as a result of a concerted action of a number of European consuls general in Egypt, were not part of the capitulations system. To the contrary, they were designed to restrict the legal side of that system, that is, consular jurisdiction.
Chemical Analysis of Some Umayyad Dirhems Minted at Wasit
Authors: Al-Saaaed Ziad 
Published: June 2004

AbstractThis study deals with the stylistic and chemical analysis of a collection of Umayyad silver coins minted at W®sit in the period between A. H. 90 (A. D. 708) – A. H. 124 (A. D. 741). The stylistic analysis shows that the coins are typical of the post-reform Islamic silver coinage as they were purely Arabic. The x-ray fluorescence results indicate that the coins have a high level of fineness with an average silver content of 94.71%. The results also signify that there had been a clear trend toward the production finer dirhems over time. One may infer a high level of quality control and strict monetary policies adopted by the various govenors of Wasit.
Prices in Hellenistic Babylonia
Authors: Grainger John 
Published: June 2004

AbstractA record of prices of basic commodities from Hellenistic Babylonia, even though incomplete, provides unusually detailed information about economic conditions there. From these prices, particularly for food, it is possible to derive conclusions concerning price levels and standards of living over a period of three centuries or so. The Seleucid period is revealed as one of high prosperity, building on a previous advance, but it was followed by a fall in living standards during the first century of Parthian rule.
Development of an efficient PCR-based diagnosis protocol for the identification of the pinewood nematode, Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae)
Authors: Kang Jae Soon , Choi Kwang Sik , Shin Sang Chul , Moon Il Sung , Lee Sang Gil , Lee Si Hyeock 
Published: June 2004

Abstract
Pine wood wilt disease caused by the pine wood nematode, Bursaphelenchus
xylophilus , has been a serious problem in the southern regions of Korea.
Efficient diagnosis of B. xylophilus from infected pine wood specimens is
critical for the management of this pest. Traditional microscopic
examination often results in an erroneous identification because a closely
related non-pathogenic species, B. mucronatus, has a great degree of
morphological similarity to B. xylophilus. In an attempt to search for
reliable molecular markers for the discrimination of these species, we have
cloned the 5S rRNA genomic DNA fragments containing both coding and
intergenic spacer (IGS) regions from B. xylophilus and B. mucronatus through
a homology-probing PCR strategy. Sequence analyses revealed that coding
sequences of the 5S rRNA gene from the two species are almost identical
(98.3% homology) but that the IGS sequences differ substantially between the
species. Based on the IGS sequence differences (69.7% homology), we designed
species-specific primer sets and developed a PCR-based diagnosis protocol
for the identification and discrimination of the two nematode species on a
molecular basis.
Hatching behaviour and life cycle of Heterodera latipons Franklin under Syrian agro-ecological conditions
Authors: Scholz Uwe , Sikora And Richard 
Published: June 2004

AbstractThe cereal cyst nematode Heterodera latipons Franklin is widespread in the eastern Mediterranean area and often occurs in mixed populations with H. avenae in cereal cropping systems. Differences between the two species in hatching behaviour and development cycle may be factors responsible for the low level of detection of H. latipons in the region. The aim of this study was to investigate the influence of different temperature regimes, agro-ecosystem, sampling date, cyst age and barley root diffusate on the hatching behaviour of H. latipons and its life cycle. The investigations were conducted by observing hatch and development under both field and glasshouse conditions. The optimum temperature for hatching was 10°C. The hatched second-stage juveniles of H. latipons from the dry and wet agro-ecological zones are found in the soil from December to April with peak densities in January and February. Thirty to 45% of the eggs of both populations from the dry and wet zone hatch slowly over the growing season. The results of hatching tests, simulating pre-planting soil temperatures in Syria, indicate that treatment for 16 days at 5°C initiates the hatching cycle of H. latipons. There was no significant difference in total hatch when cysts were placed in tap water or in barley root diffusates.
Susceptibility of neotropical mosquito larvae (Diptera: Culicidae) and non-target aquatic organisms to the entomoparasitic nematode Strelkovimermis spiculatus Poinar & Camino, 1986 (Nematoda: Mermithidae)
Authors: Achinelly María , Micieli María , Marti Gerardo , García Juan 
Published: June 2004

Abstract
Fourteen species of mosquito and several species of non-target aquatic
organisms were tested for susceptibility to the neotropical mermithid
nematode, Strelkovimermis spiculatus . All species of Aedes, Anopheles,
Culex, Isostomyia and Ochlerotatus, plus one of the two Psorophora species
exposed to S. spiculatus preparasites, were parasitised. None of the
non-target aquatic organisms exposed to S. spiculatus were infected, with
the exception of Chironomidae larvae in which nematode penetration was
observed although host reaction in the form of nematode melanisation
occurred 24-48 h post-infection, the nematodes dying within the host.
Separation of Globodera rostochiensis and G. pallida (Tylenchida: Heteroderidae) using morphology and morphometrics
Authors: Manduric Sanja , Olsson Edda , Englund Jan-Eric , Andersson Stig 
Published: June 2004

AbstractTwo Globodera rostochiensis and two G. pallida populations (pure and mixed) were analysed by identification methods based on morphology/morphometrics. To assess the accuracy of the identification, PCR analysis was performed on the same specimens. The investigation comprised juveniles, cysts and males. Seven of the most commonly used morphological/morphometric characters were examined: stylet length, length of stylet shaft plus knobs and stylet knob shape of second-stage juveniles; number of cuticular ridges between anus and vulval basin, distance between anus and vulval basin and Granek's ratio of cysts; and spicule shape of males. Altogether, 480 specimens were analysed and assessed. There were statistically significant differences between means of the G. rostochiensis and G. pallida populations in most characters and, in part, between populations of the same species. However, no individual morphological-morphometric character proved to be discriminant for species determination as in all cases there was a large overlap. A statistical discriminant analysis showed that with our populations, the values of a commonly used table of characters for separation of the two species had to be adjusted in order to produce the break points. By judging more than one character, the identification process could be considerably improved, suggesting the possibility of designing a computerised expert system.
Australodorus enigmaticus n. g., n. sp. (Nematoda: Longidoridae) from Uruguay
Authors: Coomans August , Olmos Isis , Casella Enrique , Chaves Eliseo 
Published: June 2004

Abstract Australodorus enigmaticus, a new genus and species of Longidoridae, is described from an area of previously uncultivated soil inside a Citrus plantation in Uruguay. The genus belongs to the Xiphidorini and is characterised by a well offset lip region, bilobed amphidial fovea with large slit-like aperture, slender odontostyle with forked base, weakly flanged odontophore and posteriorly located guide ring. Females have uteri without pars dilatata and males have the ventromedian supplements outside the range of the spicules. The tail is short convex-conoid in both sexes. The genus comes close to Paraxiphidorus and Xiphidorus but differs in the shape of the amphidial fovea. The only species so far known is a long (5-7.5 mm) and slender (a = 115-190), amphimictically reproducing form with a 1:1 sex ratio.