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141.
We tested the hypothesis that, during sepsis, the balance of pro- and anti-inflammatory cytokines is related to severity and survival. Cecal ligation and puncture (CLP) with a large (18-gauge)-, intermediate (21-gauge)-, or small (26-gauge)-diameter needle, or sham laparotomy, was performed on outbred CD-1 mice. Concentrations of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and the anti-inflammatory cytokine IL-10 were measured (by enzyme-linked immunosorbent assay) in serum, peritoneal lavage fluid, and liver and lung samples at 4, 8, 24, 48, and 96 h. As the diameter of the CLP needle decreased, the mortality rate decreased (at 48 h: large, 80%; intermediate, 40%; small, 20%; P < 0.05), the TNF-alpha and IL-6 concentrations decreased, and the time-to-peak TNF-alpha expression increased. In contrast, IL-10 concentration increased compared with baseline (serum at 24 h: large, 2.3-fold +/- 1.6-fold; intermediate, 2.0-fold +/- 0.5-fold; small, 49.9-fold +/- 8.3-fold; P < 0.05). Administration of IL-10 (5 microg, intraperitoneal) prior to CLP decreased mortality (P < 0.001). Administration of polyclonal anti-IL-10 serum prior to CLP (0.5 ml intraperitoneal) had the opposite effect and increased mortality (P < 0.001) and TNF-alpha, IL-6, and TNF-alpha mRNA expression compared with controls. Thus, severe sepsis is associated with a largely unopposed inflammatory response, and a largely unopposed inflammatory response (with anti-IL-10) results in severe sepsis and death. Less severe sepsis is associated with greater anti-inflammatory mediator expression, and greater anti-inflammatory mediator expression (with IL-10) results in less severe sepsis. Thus, the balance of inflammatory mediators is related to the severity and mortality of murine sepsis.  相似文献   
142.
Inheritance patterns of multiple sclerosis (MS) in multiplex families suggest a complex aetiology involving environmental and genetically determined components. The association between the HLA class II DR15, DQ6, Dw2 haplotype and MS has been well documented in patients with ancestral origins in Northern Europe. Conversely, linkage analysis of this region in multiplex families, derived from a population base, has generated negative results. Thus, given the Dw2 specificity association, evidence implicating this locus in disease susceptibility appears contradictory. We have collected and determined the HLA-DR and -DQ haplotypes of 115 sibling pairs with multiple sclerosis, and confirm a significant association with the Dw2-associated haplotype, both in index cases and their affected siblings compared with controls. However, using a sibling pair linkage analysis that restricts haplotype sharing probabilities to defined genetic models, we have not observed linkage of this region to susceptibility in MS. We discuss the basis for association and linkage and conclude that the DR15, DQ6, Dw2 haplotype does represent a susceptibility locus but its contribution to the pathogenesis is small; although it may interact epistatically with other susceptibility genes, this haplotype is not necessary for disease expression.  相似文献   
143.
The hypoglycemic effect of the rhizomes of Polygala senega L. var. latifolia Torrey et Gray (Polygalaceae) was investigated in normal and KK-Ay mice, one of the model animals of non-insulin dependent diabetes mellitus (NIDDM). The n-butanol extract of senega rhizomes (SN) (5 mg/kg) reduced the blood glucose of normal mice from 191 +/- 3 to 120 +/- 3 mg/dl 4 hours after intraperitoneal administration (P < 0.001), and also showed a significant decrease in the glucose level of KK-Ay mice from 469 +/- 38 to 244 +/- 14 mg/dl under similar conditions (P < 0.001). But streptozotocin-induced diabetic mice did not experience a change in the blood glucose after administration of SN. We propose that the hypoglycemic effect of SN occurs without altering the insulin concentration. Moreover, SN needs the presence of insulin in order to act. In addition, one of the active components of the hypoglycemic effect was identified as a triterpenoid glycoside, senegin-II.  相似文献   
144.
145.
The mol percentage of 5-hydroxymethylcytosine is 2.2 times greater in the adult than in 2-day-old rat brain DNA. The concentration of 5-hydroxymethylcytosine falls in corresponding liver DNA preparations. This normal increase in brain 5-hydroxymethylcytosine is abolished in rats placed on an 8%-protein diet 5 days after birth.  相似文献   
146.
Reaction centers isolated from three large-scale symmetry mutants sym0, sym2-1, and sym5-2 described in the previous article of this issue [Taguchi, A. K. W., Eastman, J. E., Gallo, D. M., Jr., Sheagley, E.. Xiao, W., & Woodbury, N. W. (1996) Biochemistry 35, 3175-3186] have been investigated by low-temperature ground state and ferntosecond-resolution transient absorption spectroscopy. All three of these large-scale symmetry mutants undergo electron transfer at 20 K. The mutants sym0 and sym5-2 have yields and dominant rates of charge separation comparable to wild type. However. the sym2-mutant shows a roughly 35%, quantum yield at this temperature, and the major kinetic component of the initial electron transfer is slower than wild type by nearly a factor of 100. The sym0 mutant showed substantial changes in the monomer bacteriochiorophyll ground state and transient spectra, and both sym0 sym2-1 showed changes in the bacteriopheophyll ground state and transient spectra. In particular, sym2-1 shows a small absorbance decrease in the region of the Qx band of the B side bacteriopheophytin which could be attributed to 10%-20% electron transfer along the B pathway.  相似文献   
147.
The Eph family of receptor tyrosine kinases has 13 distinct members and seven ligands for these receptors have been described to date. These receptors and their ligands have been implicated in regulating neuronal axon guidance and in patterning of the developing nervous system and may also serve a patterning and compartmentalization role outside of the nervous system as well. The ligands are all membrane-attached, and this attachment appears to be crucial for their normal function; five of the known ligands are linked to the membrane via a glycosyl phosphotidylinositol (GPI) linkage, while two of the ligands are transmembrane proteins. Despite the large number of Eph family receptors and ligands, they can be divided into just two major subclasses based on their binding specificities. All the GPI-anchored ligands bind and activate one subclass of the Eph receptors (that represented by Eck) while the two transmembrane ligands bind and activate the other major subclass of receptors (represented by Elk). Here we report the identification and characterization of the third, and most divergent, member of the transmembrane group of Eph ligands, which we term Elk-L3 (Elk-related receptor ligand number 3). Elk-L3 is notable for its remarkably restricted and prominent expression in the floor plate and roof plate of the developing neural tube and its rhombomere-specific expression in the developing hindbrain. The Elk-L3 gene has been localized to mouse chromosome 11 and human chromosome 17.  相似文献   
148.
The number of individuals diagnosed with diabetes mellitus is increasing. The diabetic may present with complications involving all systems of the body. While onychomycosis is often observed in diabetics, there have been no large studies on the prevalence of the condition in this patient group. We examined the prevalence of onychomycosis in diabetics attending diabetes and dermatology clinics in London, Ontario, Canada and Boston, MA, U.S.A. Diabetic subjects seen in dermatology offices were for unrelated dermatoses; those referred specifically for the management of onychomycosis were excluded from the sample. A total of 550 diabetic subjects was evaluated (283 males and 267 females), age 56.1 +/- 0.7 years (mean +/- SEM). Patients with type I diabetes constituted 34% of the sample. The racial origin was: 531 Caucasians, 17 Asians, one African-American and one American-Indian. Abnormal-appearing nails and mycological evidence of onychomycosis (mostly due to dermatophytes) were present in 253 (46%) and 144 (26%), respectively, of 550 subjects. The development of onychomycosis was significantly correlated with age (P < 0.0001) and male gender (P < 0.0001). Males were 2.99 times more likely to have onychomycosis compared with females (95% confidence interval, CI 1.94-4 61). After controlling for age and sex, the risk odds ratio for diabetic subjects to have toenail onychomycosis was 2.77 times compared with normal individuals (95% CI 2.15-3.57). After controlling for age and sex, a stepwise logistic regression demonstrated that significant predictors for onychomycosis included a family history of onychomycosis (P = 0.0001), concurrent intake of immunosuppressive therapy (P = 0.035) and peripheral vascular disease (P = 0.023). Toenail onychomycosis was present in 26% of the sample and is projected to affect approximately one-third of subjects with diabetes. Predisposing factors include increasing age, male gender, family history of onychomycosis, concurrent intake of immunosuppressive agents and peripheral vascular disease.  相似文献   
149.
150.
A patient with severe and protracted symptoms from intracranial hypotension is described. The patient's presentation was marked by diffuse encephalopathy and profound depression of consciousness. This case report expands the presently known clinical spectrum of this uncommon and generally benign illness. The clinical and laboratory findings typically observed in the syndrome of intracranial hypotension are outlined. The pathophysiological mechanisms of the phenomenon are briefly discussed. Intracranial hypotension is a potentially severe illness with specific treatments that are distinct from the treatment of most neurological diseases. Three cardinal features--postural headache, pachymeningitis, and descent of midline cerebral structures--should prompt the diagnosis.  相似文献   
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