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The prevalence of infection of the West Australian dhufish Glaucosoma hebraicum off the lower west coast of Australia by Philometra lateolabracis was greater among females than males, which contrasts with the situation with Pagrus auratus in waters off New Zealand. Live P. lateolabracis were represented solely by females and were found only in the gonads of fish of mature size ( L 50 at first maturity = c . 300 mm) caught between December and April and thus during the spawning period of dhufish. Since the gonads were largest during that period, they, and particularly ovaries, would provide an abundant food source in the form of blood. The prevalence of the parasite (live + dead individuals) increased with host body size to reach a maximum of c . 80% in the 700–799 mm length class of females and c . 50% in the largest length class of males. During the spawning period of G hebraicum, P. lateolabracis developed from small, non-gravid females to large gravid females, representing an increase in mass of more than 200 times. The maximum length of P. lateolabracis (470 mm) in G hebraicum is the greatest yet recorded for this species. Gonadosomatic indices provided no evidence that infection by P. lateolabracis leads to a conspicuous atrophy of the ovaries, which contrasts with the situation with the gonads of some of the teleosts infected by Philometra species, and presumably reflects, in part, the small volume of the ovary occupied by P. lateolabracis (c . 3%) and the low intensity of infection (mean = 2.0, maximum = 7). Although the presence of live P. lateolabracis did not stimulate an obvious tissue response by the ovaries during the spawning period of G. hebraicum , both the dead and any live parasites that remain after spawning become encapsulated in fibrous tissue. 相似文献
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B F Eldridge C H Calisher J L Fryer L Bright D J Hobbs 《Journal of wildlife diseases》1987,23(2):199-204
We wished to demonstrate evidence of the presence of California serogroup viruses in Oregon and to test for the presence of certain other arboviruses in large ungulates. Blood samples from black-tailed deer (Odocoileus hemionus columbianus), mule deer (O. hemionus hemionus), and Roosevelt elk (Cervus elaphus roosevelti) from nine counties in Oregon were tested by serum-dilution plaque reduction neutralization for antibody to California serogroup viruses, including snowshoe hare, California encephalitis, and Jamestown Canyon, as well as to Cache Valley (Bunyamwera serogroup) and Klamath, an ungrouped rhabdovirus. Of 132 samples tested, 60 (46%) were found to be seropositive at a dilution of greater than or equal to 1:10 for at least one of the five different arboviruses. Forty (30%) samples contained antibody to more than one arbovirus, and 15 samples (11%) contained antibody to all five. Of these 15, 14 were from 75 black-tailed deer sera collected in Lincoln County, Oregon. Seropositivity rates for black-tailed deer ranged from 23% to 35%, with all five arboviruses represented. Positive reactions for all five arboviruses were represented among mule deer sera at rates from 5% to 29%. Elk sera were found to be positive for four of the viruses (none for Klamath virus). Although Cache Valley and Klamath viruses have been reported from Oregon, these data represent the first evidence of a California serogroup virus in the state. 相似文献
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In the mouse neuroblastoma x dorsal root ganglion hybrid cell line F-11, bradykinin receptor stimulation induced the release of inositol-1,4,5-trisphosphate (IP3) and inositol-1,4-bisphosphate (IP2). Maximal stimulation of [2-3H]IP3 and [2-3H]IP2 release by bradykinin in the absence of LiCl occurred at 7 (or less) and 15 s, respectively, with average levels of 5.7-(IP3) and 3.4-(IP2) fold of control values. The EC50 for bradykinin was 33 +/- 5 nM. IP3 and IP2 concentrations returned to basal levels approximately 1 min after bradykinin addition. Bradykinin-induced IP3 release was blocked by several novel bradykinin analogues. In particular, [D-Arg0]-Hyp3-Thi5,8-[D-Phe7]-bradykinin [Hyp, hydroxyproline; Thi, beta-(2-thienyl)-L-alanine] blocked IP3 production in a dose-dependent fashion. Several of these analogues alone showed little or no agonist activity. The bradykinin receptor may be coupled to phospholipase C via a GTP-sensitive protein (Gi or Go), as preincubation for 18-20 h with pertussis toxin decreased IP3 concentrations by 45%. Bradykinin is also known to modulate the concentrations of other second messengers in neurons, increasing the concentrations of Ca2+, diacylglycerol (DG), and cyclic GMP and decreasing the concentration of cyclic AMP. These second messengers modulated bradykinin-dependent IP3 release to varying degrees. A23187, a Ca2+ ionophore, produced a 37% decrease in IP3 concentration. 12-O-Tetradecanoylphorbol-13-acetate, which mimics the effects of DG and activates protein kinase C, inhibited IP3 release by 80%. Dibutyryl cyclic GMP produced little or no inhibition of IP3. [D-Ala2,D-Leu5]Enkephalin (DADLE), an opioid peptide that decreases cyclic AMP concentrations, likewise had no effect.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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A Vellodi J R Hobbs N M O'Donnell B S Coulter K Hugh-Jones 《BMJ (Clinical research ed.)》1987,295(6610):1375-1376
Allogenic bone marrow transplantation was carried out on a 3 year old girl with Niemann-Pick disease type B. Successful engraftment was achieved, and nine months after the procedure there was definite clearing of the sphingomyelin from the liver and pronounced clearing from the bone marrow. Any patient with Niemann-Pick disease type B complicated by early or severe hepatic impairment should be considered for bone marrow transplantation. 相似文献
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Mutations in the low-density lipoprotein (LDL) receptor gene result in the autosomal dominant disorder familial hypercholesterolemia (FH). Many different LDL receptor mutations have been identified and characterized, demonstrating a high degree of allelic heterogeneity at this locus. The ability to identify mutant LDL receptor genes for prenatal diagnosis of homozygous FH or to study the role of the LDL receptor gene in polygenic hypercholesterolemia requires the use of closely linked RFLPs. In the present study we used 10 different RFLPs, including three newly described polymorphisms, to construct 123 independent haplotypes from 20 Caucasian American pedigrees. Our sample contained 31 different haplotypes varying in frequency from 0.8% to 29.3%; the five most common haplotypes account for 67.5% of the sample. The heterozygosity and PIC of each site were determined, and these values disclosed that eight of the RFLPs were substantially polymorphic. Linkage-disequilibrium analysis of the haplotype data revealed strong nonrandom associations among all 10 RFLPs, especially among those sites clustered in the 3' region of the gene. Evolutionary analysis suggests the occurrence of both mutational and recombinational events in the generation of the observed haplotypes. A strategy for haplotype analysis of the LDL receptor gene in individuals of Caucasian American descent is presented. 相似文献
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Opsonization of Staphylococcus aureus (Oxford strain) and specific IgG subclass antibodies against formalised staphylococci were measured in plasmas from 27 patients with significant S. aureus infections and 35 healthy adults and 15 children. There were no statistically significant differences in the IgG2 and IgG4 levels between two groups and IgG3 was not detected, but the median plasma IgG1 level was significantly higher in patients with staphylococcal infections (P less than 0.00003). The concentration of IgG2 anti-S. aureus antibodies was 25-47 times greater than that of IgG1. If plasmas were decomplemented, the raised IgG1 levels were associated with increased opsonophagocytosis by normal neutrophils (P less than 0.0002). 相似文献
10.
Induction of IL-1 secretion from human monocytes by Fc region subfragments of human IgG1 总被引:1,自引:0,他引:1
E L Morgan M V Hobbs D J Noonan W O Weigle 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(9):3014-3020
Peripheral blood-derived human monocytes and the murine P388D1-monocytes-like cell line are induced to secrete IL-1 when stimulated with Fc region but not F(ab) region subfragments obtained from the cleavage of human IgG1 with papain or pepsin. The portion of the Fc region of IgG1 responsible for stimulation of IL-1 secretion appears to be located within the C gamma 3 domain of the molecule. This hypothesis is supported by the observation that the biologically active pepsin-derived pFc' subfragment is located within the C gamma 3 domain and the long-term papain digests containing predominately Fc' are also active. In contrast, short term papain digests containing mostly intact Fc fragments were found to be unable to induce IL-1 secretion. 相似文献