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1.
Smith IC Huang J Quadrilatero J Tupling AR Vandenboom R 《Journal of muscle research and cell motility》2010,31(4):267-277
X-linked muscular dystrophy of the mouse (mdx) has been reported to progressively remodel skeletal muscle to preferentially reduce fast fiber composition. Despite this,
mdx muscle displays normal levels of posttetanic potentiation (PTP). Since PTP may primarily depend on phosphorylation of the
myosin regulatory light chain (RLC) in fast muscle fibers, maintenance of PTP with mdx disease progression is paradoxical and may represent an adaptation of the diseased muscle. This study assesses the role of
RLC phosphorylation during PTP of mdx muscle. Extensor digitorum longus muscles were isolated from mdx and from C57BL/10 (control) mice at ~50 (young) and ~300 (adult) days and stimulated in vitro (25°C) to induce PTP. During
potentiation, muscles were harvested for subsequent determination of RLC phosphorylation levels. Immunofluorescence was used
to assess muscle fiber type composition and no age effects were found. The magnitude of PTP was higher (P < 0.05) in mdx than control muscles at both young (mdx: 21.9 ± 1.6%; control: 17.7 ± 1.2%) and adult (mdx: 30.4 ± 1.8%; control: 23.2 ± 2.2%) ages. However, RLC phosphate content was similar between all groups both at rest and
following stimulation. Our results are consistent with a model where the sensitivity of mdx muscle to RLC phosphorylation-induced force potentiation is increased by disease- and age-dependent alterations in excitation-contraction
coupling noted for mdx and aging muscle. 相似文献
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3.
María del Rosario Robles James E. Loudon John M. Kinsella Mandala Hunter-Ishikawa David S. Miller Michelle L. Sauther Frank P. Cuozzo 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2010,55(3):270-275
Lemuricola (Madoxyuris) bauchoti Chabaud, Brygoo et Petter, 1965 is redescribed from material collected from the ring-tailed lemur, Lemur catta, from the Beza Mahafaly Special Reserve in Madagascar using the scanning electron microscope. This is a new host record and
the first oxyurid reported from the ring-tailed lemur. Previously, records of each species of the subgenus Madoxyuris have been restricted to a single host species, but the close relationship between these nematodes and their Strepsirrhini
hosts will only be proven when additional records fill in the gaps in their distribution. 相似文献
4.
Karina?M.?Rebello Luzia?M.?C.?C?rtes Bernardo?A.?S.?Pereira Bernardo?M.?O.?Pascarelli Suzana?C?rte-Real Léa?C.?Finkelstein Rosa?T.?Pinho Claudia?M.?d’Avila-Levy Carlos?R.?Alves 《Parasitology research》2009,106(1):95-104
Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and
is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we
obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of
63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the
peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data
together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation
of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant
and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that
some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues
in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection. 相似文献
5.
All trypanosome species classified in the subgenus Herpetosoma in sciurid hosts have been recorded from ground and tree squirrels to date, but not from any flying squirrels. We describe in this paper a novel trypanosome species, Trypanosoma (Herpetosoma) kuseli sp. n., from Siberian flying squirrels (Pteromys volans) imported from China, and compare it with T. (H.) otospermophili in Richardson's ground squirrels (Spermophilus richardsonii) and Columbian ground squirrels (Spermophilus columbianus) from the USA. Due to a short free flagellum, the new species appeared stumpy compared with T. otospermophili (length of free flagellum 7.0 +/- 0.8 microm, total length 32.1 +/- 0.8 microm, n = 13 and length of free flagellum 15.5 +/- 1.6 microm, total length 35.9 +/- 1.0 microm, n = 13, respectively). Another conspicuous morphological feature of the new species was an anteriorly positioned kinetoplast, found approximately at the midpoint between the nucleus and the posterior end. These characters have not been recorded from any squirrel Herpetosoma trypanosome species. Comparison of the nucleotide sequences of the small and large subunit rRNA genes indicated that T. kuseli sp. n. was more homologous to T. otospermophili than murid Herpetosoma species, such as T. grosi, T. lewisi, T. musculi, T. microti and T. evotomys. 相似文献
6.
Reichard MV Torretti L Snider TA Garvon JM Marucci G Pozio E 《Parasitology research》2008,103(3):657-661
Infection of Trichinella spp. is common among animals in the Canadian Arctic. We determined the prevalence of Trichinella spp. infection in wolverines (Gulo gulo) from Nunavut, Canada. Diaphragms from 41 wolverines were examined by artificial digestion. Trichinella spp. larvae were detected in 36 (87.8%) examined animals. Trichinella T6 was detected in 33 (91.7%), Trichinella nativa in only one (2.8%), and a mixed Trichinella T6 and T. nativa infections were detected in two (5.6%) wolverines. This is the first report of Trichinella spp. infection in wolverines from Nunavut and the first report of sympatric Trichinella T6 and T. nativa in any host. The high prevalence of Trichinella spp. infection in combination with the natural history of wolverines suggests that the mustelid may be a key species in the natural cycle of these parasites in Arctic and Subarctic areas. 相似文献
7.
Weihuan Huang Xiaoli Zhang Yifei Wang Wencai Ye Vincent EC Ooi Hau Yin Chung Yaolan Li 《Chinese medicine》2010,5(1):23
Background
Radix Wikstroemiae is a common Chinese herbal medicine. The ethyl acetate fraction of the ethanolic extract of W. indica possesses potent in vitro antiviral activity against respiratory syncytial virus (RSV). This study aims to identify the antiviral components of the active fraction. 相似文献8.
Galba truncatula snails were experimentally infected with either of two different isolates of Fasciola gigantica, originating from Egypt or China, to determine the influence of these isolates on the characteristics of snail infections. The survival rates of G. truncatula on day 30 post-exposure were 90.0% and 60.2% in the Egyptian and Chinese groups, respectively. The frequency of cercaria-shedding snails within the Egyptian group was 79.8%, whereas in the Chinese group it was 22.4%. The parasite origin had a significant effect on the durations of the prepatent and patent periods. The mean number of cercariae shed from the Egyptian group was significantly greater than that shed from the Chinese group (a mean of 275.5 per cercaria-shedding snail compared with 29.0). These results could be explained by the fact that G. truncatula might be a natural intermediate host for F. gigantica in Egypt, and the greater adaptability of the Egyptian miracidia of F. gigantica to unusual snail hosts. These results demonstrate the influence of the geographic origin of the parasite on the success of trematodes infecting snails. 相似文献
9.
Mara A. Correa Tatiane Canhamero Andrea Borrego Iana S. S. Katz José R. Jensen José Luiz Guerra Wafa H. K. Cabrera Nancy Starobinas Jussara G. Fernandes Orlando G. Ribeiro Olga M. Ibañez Marcelo De Franco 《Inflammation research》2017,66(11):969-980
Objective and design
Pristane-induced arthritis (PIA) in AIRmax mice homozygous for Slc11a1 R and S alleles was used to characterize the influence of Slc11a1 gene polymorphism on immune responses during disease manifestation. Previous reports demonstrated that the presence of the Slc11a1 S allele increased the incidence and severity of PIA in AIRmax SS , suggesting that this gene could interact with inflammatory loci to modulate PIA. We investigated the effects of Slc11a1 alleles on the activation of phagocytes during PIA.Treatment
Mice were injected intraperitoneally with two doses of 0.5 mL of mineral oil pristane at 60-day intervals. Arthritis development was accompanied for 180 days.Results
AIRmax SS mice showed differential peritoneal macrophage gene expression profiles during PIA, with higher expression and production of H2O2, NO, IL-1β, IL-6, TNF-α, and several chemokines. The presence of the Slc11a1 R allele, on the other hand, diminished the intensity of macrophage activation, restricting arthritis development.Conclusion
Our data demonstrated the fine-tuning roles of Slc11a1 alleles modulating macrophage activation, and consequent PIA susceptibility, in those mouse lines.10.
Repeat induced point mutation (RIP) is a gene silencing mechanism present in fungal genomes. During RIP, duplicated sequences
are efficiently and irreversibly mutated by transitions from C:G to T:A. For the first time, we have identified traces of
RIP in transposable elements of Aspergillus niger and Penicillium chrysogenum, two biotechnologically relevant fungi. We found that RIP in P. chrysogenum has affected a large set of sequences, which also contain other mutations. On the other hand, RIP in A. niger is limited to only few sequences, but literally all mutations are RIP-like. Surprisingly, RIP occurred only in transposon
sequences that have disrupted open reading frames in A. niger, a phenomenon not yet reported for other fungi. In both fungal species, we identified two sequences with strong sequence
similarity to Neurospora crassa RID. RID is a putative DNA methyltransferase and the only known enzyme involved in the RIP process. Our findings suggest
that both A. niger and P. chrysogenum either had a sexual past or have a sexual potential. These findings have important implications for future strain development
of these fungi. 相似文献
11.
Bardia A Tiwari SK Gunisetty S Anjum F Nallari P Habeeb MA Khan AA 《Inflammation research》2012,61(4):359-365
Objective
The present study was designed to investigate the role of X-ray cross-complementing group 1 (XRCC1) and apurinic/apyrimidinic endonuclease 1 (APE1) polymorphisms in apoptosis and the risk of ulcerative colitis (UC). 相似文献12.
13.
Occurrence of <Emphasis Type="Italic">Cryptosporidium hominis</Emphasis> in pigeons (<Emphasis Type="Italic">Columba livia</Emphasis>) 总被引:1,自引:0,他引:1
Néstor Abreu-Acosta Pilar Foronda-Rodríguez Mercedes López Basilio Valladares 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2009,54(1):1-5
This study demonstrated the presence of Cryptosporidium hominis in pigeons for the first time. Previously, C. hominis had been cited only in another bird species, Branta canadiensis. The present findings suggest that pigeons may act as mechanical vectors for this protozoan. 相似文献
14.
Passero LF Carvalho AK Bordon ML Bonfim-Melo A Toyama MH Corbett CE Laurenti MD 《Inflammation research》2012,61(3):255-263
Objective
Leishmania (Viannia) shawi was characterized only recently, and few studies concerning the immunogenic and protective properties of its antigens have been performed. The present study aimed to evaluate the protective potential of the five antigenic fractions isolated from L. (V.) shawi promastigotes in experimental cutaneous leishmaniasis. 相似文献15.
Silva-Lopez RE Morgado-Díaz JA Alves CR Côrte-Real S Giovanni-De-Simone S 《Parasitology research》2004,93(4):328-331
Extracellular proteolytic activity was detected in a Leishmania (L.) amazonensis culture supernatant and a 56-kDa protein was purified using (NH4)2SO4 precipitation followed by affinity chromatography on aprotinin–agarose. A rabbit serum obtained against the 56-kDa extracellular serine protease was used in order to analyze its location in L. (L.) amazonensis parasites. Immunocytochemistry studies revealed that the enzyme is mainly found in the flagellar pocket and cytoplasmic vesicles of promastigote forms, whereas in amastigotes, it is located in electron-dense structures resembling megasomes. These results indicate that the 56-kDa serine protease is released into the extracellular environment through the flagellar pocket; and its intracellular location suggests either a correlated enzymatic activity or intracellular trafficking. 相似文献
16.
Zlatka M. Dimitrova 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2009,54(1):53-56
In total, 2097 individuals of Trachelipus squamuliger and 20 individuals of Armadillidium vulgare from four habitats (three woodland sites and one pasture) in the region of Stara Zagora, Bulgaria, were examined for the
presence of cystacanths of Plagiorhynchus cylindraceus, a common acanthocephalan parasite of passerine birds. In T. squamuliger from woodland habitats, cystacanths were found with prevalence 4.0–9.3%, intensity 1–5 (mean 1.22–1.57) and mean abundance
0.057–0.113. No significant differences were observed between infections in males and females of T. squamuliger. None of the T. squamuliger individuals from the pasture examined was infected. Out of 48 infected females of T. squamuliger, only one had developed eggs (in agreement with previous studies revealing the negative effect of the cystacanths on the
development of female gonads of woodlice). One individual of A. vulgare was infected with a single cystacanth. The occurrence of P. cylindraceus in T. squamuliger is a new host record. 相似文献
17.
Emily Staples Beatriz Morillo-Gutierrez Jessica Davies Daniel Petersheim Michel Massaad Mary Slatter Dimitra Dimou Rainer Doffinger Scott Hackett Dinkantha Kumararatne James Hadfield Matthew D. Eldridge Raif S. Geha Mario Abinun James E. D. Thaventhiran 《Journal of clinical immunology》2017,37(5):415-418
18.
Pseudomonas aeruginosa is an opportunistic pathogen of immunocompromised hosts. In cystic fibrosis (CF), P. aeruginosa causes acute and chronic lung infections that result in significant morbidity and mortality. P. aeruginosa possesses several traits that contribute to its ability to colonize and persist in acute and chronic infections. These include
high resistance to antimicrobials, ability to form biofilms, plethora of virulence products, and metabolic versatility. In
P. aeruginosa, a cell-to-cell communication process termed quorum sensing (QS) regulates many of these factors that contribute to its pathogenesis.
Recent evidence suggests that the CF lung environment presents a specialized niche for P. aeruginosa. The relationship of P. aeruginosa QS, biofilm formation, and the CF lung environment is discussed. 相似文献
19.
M. Friedemann 《European journal of clinical microbiology & infectious diseases》2009,28(11):1297-1304
About 120–150 neonatal Cronobacter spp. (Enterobacter sakazakii) infections have been described. An analysis of current case numbers, epidemiological measures and risk factors is warranted.
Data of microbiologically confirmed cases, published between 2000 and 2008, have been analysed statistically. More than 100
neonatal Cronobacter infections have been reported in this period. The overall lethality of the 67 invasive infections was 26.9%. The lethality
of Cronobacter meningitis, bacteraemia and necrotising enterocolitis (NEC) was calculated to be 41.9% (P < 0.0001), <10% and 19.0% (P < 0.05), respectively. Logistic regression models (P < 0.0001) revealed a higher gestational age at birth and parentage not from Europe as significant factors for a higher reporting
probability of neonatal Cronobacter meningitis. Neonates with Cronobacter meningitis not originating from North America have a higher risk for lethal outcome than other neonatal Cronobacter infections (P < 0.0001). Continental differences of risk factors for Cronobacter meningitis and for the lethal outcome of neonatal meningitis should be elucidated. Neonatal Cronobacter infections are mainly associated with the contamination of infant formula and of the relevant cleaning and preparation equipment.
Eleven neonatal Cronobacter infections, not caused by contaminated infant formula, have been retrieved. Other environmental sources of infection should
be considered. Consistent and sufficiently informative data of invasive neonatal Cronobacter infections should be recorded in a centralized reporting system. 相似文献