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111.
PurposeTo review and discuss the methods used for measuring spinal stiffness and factors associated with stiffness, how stiffness is used in diagnosis, prognosis, and treatment decision-making and the effects of manipulative techniques on stiffness.MethodsA systematic search of MEDLINE, EMBASE, CINAHL, AMED and ICL databases was conducted. Included studies addressed one of four constructs related to stiffness: measurement, diagnosis, prognosis and/or treatment decision-making, and the effects of manipulation on stiffness. Spinal stiffness was defined as the relationship between force and displacement.ResultsOne hundred and four studies are discussed in this review, with the majority of studies focused on the measurement of stiffness, most often in asymptomatic persons. Eight studies investigated spinal stiffness in diagnosis, providing limited evidence that practitioner-judged stiffness is associated with radiographic findings of sagittal rotational mobility. Fifteen studies investigated spinal stiffness in prognosis or treatment decision-making, providing limited evidence that spinal stiffness is unlikely to independently predict patient outcomes, though stiffness may influence a practitioner’s application of non-thrust manipulative techniques. Nine studies investigating the effects of manipulative techniques on spinal stiffness provide very limited evidence that there is no change in spinal stiffness following thrust or non-thrust manipulation in asymptomatic individuals and non-thrust techniques in symptomatic persons, with only one study supporting an immediate, but not sustained, stiffness decrease following thrust manipulation in symptomatic individuals.ConclusionsThe existing limited evidence does not support an association between spinal stiffness and manipulative treatment outcomes. There is a need for additional research investigating the effects of manipulation on spinal stiffness in persons with spinal pain.  相似文献   
112.
The signalling activities of Merlin and Moesin, two closely related members of the protein 4.1 Ezrin/Radixin/Moesin family, are regulated by conformational changes. These changes are regulated in turn by phosphorylation. The same sterile 20 kinase-Slik co-regulates Merlin or Moesin activity whereby phosphorylation inactivates Merlin, but activates Moesin. Thus, the corresponding coordinate activation of Merlin and inactivation of Moesin would require coordinated phosphatase activity. We find that Drosophila melanogaster protein phosphatase type 1 β (flapwing) fulfils this role, co-regulating dephosphorylation and altered activity of both Merlin and Moesin. Merlin or Moesin are detected in a complex with Flapwing both in-vitro and in-vivo. Directed changes in flapwing expression result in altered phosphorylation of both Merlin and Moesin. These changes in the levels of Merlin and Moesin phosphorylation following reduction of flapwing expression are associated with concomitant defects in epithelial integrity and increase in apoptosis in developing tissues such as wing imaginal discs. Functionally, the defects can be partially recapitulated by over expression of proteins that mimic constitutively phosphorylated or unphosphorylated Merlin or Moesin. Our results suggest that changes in the phosphorylation levels of Merlin and Moesin lead to changes in epithelial organization.  相似文献   
113.

Background

Integrated Management of Childhood Illness (IMCI) is a strategy to reduce mortality and morbidity in children under 5 years by improving case management of common and serious illnesses at primary health care level, and was adopted in South Africa in 1997. We report an evaluation of IMCI implementation in two provinces of South Africa.

Methodology/Principal Findings

Seventy-seven IMCI trained health workers were randomly selected and observed in 74 health facilities; 1357 consultations were observed between May 2006 and January 2007. Each health worker was observed for up to 20 consultations with sick children presenting consecutively to the facility, each child was then reassessed by an IMCI expert to determine the correct findings. Observed health workers had been trained in IMCI for an average of 32.2 months, and were observed for a mean of 17.7 consultations; 50/77(65%) HW''s had received a follow up visit after training. In most cases health workers used IMCI to assess presenting symptoms but did not implement IMCI comprehensively. All but one health worker referred to IMCI guidelines during the period of observation. 9(12%) observed health workers checked general danger signs in every child, and 14(18%) assessed all the main symptoms in every child. 51/109(46.8%) children with severe classifications were correctly identified. Nutritional status was not classified in 567/1357(47.5%) children.

Conclusion/Significance

Health workers are implementing IMCI, but assessments were frequently incomplete, and children requiring urgent referral were missed. If coverage of key child survival interventions is to be improved, interventions are required to ensure competency in identifying specific signs and to encourage comprehensive assessments of children by IMCI practitioners. The role of supervision in maintaining health worker skills needs further investigation.  相似文献   
114.
We previously demonstrated that exogenous expression of a truncated form of the tight junction protein ZO-3 affected junctional complex assembly and function. Current results indicate that this ZO-3 construct influences actin cytoskeleton dynamics more globally. We show that expression of the amino-terminal half of ZO-3 (NZO-3) in Madin-Darby canine kidney cells results in a decreased number of stress fibers and focal adhesions and causes an increased rate of cell migration in a wound healing assay. We also demonstrate that RhoA activity is reduced in NZO-3-expressing cells. We determined that ZO-3 interacts with p120 catenin and AF-6, proteins localized to the junctional complex and implicated in signaling pathways important for cytoskeleton regulation and cell motility. We also provide evidence that NZO-3 interacts directly with the C terminus of ZO-3, and we propose a model where altered interactions between ZO-3 and p120 catenin in NZO-3-expressing cells affect RhoA GTPase activity. This study reveals a potential link between ZO-3 and RhoA-related signaling events.  相似文献   
115.
In this study, we demonstrate the versatility of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOFMS) protein profiling for the species differentiation of a diverse suite of Bacillus spores. MALDI-TOFMS protein profiles of 11 different strains of Bacillus spores, encompassing nine different species, were evaluated. Bacillus species selected for MALDI-TOFMS analysis represented the spore-forming bacterial diversity of typical class 100K clean room spacecraft assembly facilities. A one-step sample treatment and MALDI-TOFMS preparation were used to minimize the sample preparation time. A library of MALDI-TOFMS spectra was created from these nine Bacillus species, the most diverse protein profiling study of the genus reported to date. Linear correlation analysis was used to successfully differentiate the MALDI-TOFMS protein profiles from all strains evaluated in this study. The MALDI-TOFMS protein profiles were compared with 16S rDNA sequences for their bacterial systematics and molecular phylogenetic affiliations. The MALDI-TOFMS profiles were found to be complementary to the 16S rDNA analysis. Proteomic studies of Bacillus subtilis 168 were pursued to identify proteins represented by the biomarker peaks in the MALDI-TOFMS spectrum. Four small, acid-soluble proteins (A, B, C, and D), one DNA binding protein, hypothetical protein ymf J, and four proteins associated with the spore coat and spore coat formation (coat JB, coat F, coat T, and spoIVA) were identified. The ability to visualize higher-molecular-mass coat proteins (10 to 25 kDa) as well as smaller proteins (<10 kDa) with MALDI-TOFMS profiling is critical for the complete and effective species differentiation of the Bacillus genus.  相似文献   
116.
The induction of tolerance in a primed immune system is a major aim for therapy in autoimmunity and transplant rejection. In this paper, we investigate the action of the nondepleting anti-CD4 Ab, YTS 177. Although this Ab is nondepleting, we have demonstrated a direct action in vivo on activated effector cells. We show that the Ab inhibits transfer of insulin-dependent diabetes mellitus by the CD4+ Th1 clone BDC2.5 to nonobese diabetic mice. Furthermore, we show that this Ab acts directly on diabetogenic effector cells because it prevented BDC2.5-induced insulin-dependent diabetes mellitus in nonobese diabetic-scid recipients in the absence of other T cells. The Ab halts the diabetic process even when it is administered after the BDC2.5 cells have infiltrated the pancreas and destruction of islets is already underway. This is accompanied by an immediate decrease in proinflammatory cytokine production with cessation of beta cell destruction and disappearance of infiltrating cells from the pancreas, leaving any remaining beta cells intact. These data suggest that Abs such as this may be effective not only because they induce regulatory T cells but also because they are able to directly prevent effector cell function.  相似文献   
117.
Summary Flag leaves of Colman forage sorghum (Sorghum bicolor) contain at least 25 times as much leucoanthocyanidin (LAC) and approximately half as much of the cyanogenic glucoside, dhurrin, as do flag leaves of White Collier forage sorghum. Assays of flag leaves from 119 F2 plants and 11 F5 lines from crosses between these two cultivars revealed a statistically significant negative association between levels of LAC and dhurrin. Both LAC and dhurrin are aromatic compounds, and the negative association between the two may be the result of competition for intermediates or products of the aromatic biosynthetic pathway. This rationale appears to be quite different from that for the negative association reported for levels of tannin and cyanide in Lotus corniculatus. Although the negative relationship between LAC and dhurrin in sorghum was statistically significant, the association was not consistent enough to suggest that either trait could be used reliably in selecting or breeding to modify the other trait.Contribution from USDA-ARS and the University of Nebraska Agric. Res. Div. Published as Paper No. 8003, Journal Series, Agric. Res. Div. The work reported was done under Agric. Res. Div. Project 12–114  相似文献   
118.
Canine mucopolysaccharidosis type VII results from deficient activity of lysosomal beta-glucuronidase. Residual enzymatic activity (0.2-1.7% of normal) was detected in tissue homogenates from affected dogs. In contrast, serum and urine from affected animals had up to 15% residual activity. To further characterize the nature of the defective enzyme, hepatic beta-glucuronidase was partially purified from normal and MPS VII dogs for determination of their physical and kinetic properties. About 65% of the total beta-glucuronidase in normal canine liver required detergent for solubilization (i.e., membrane-associated), whereas only 22% of the residual activity in canine MPS VII liver was membrane-associated. Compared to the normal hepatic enzyme, the Km towards 4-methylumbelliferyl-beta-glucuronide was markedly increased in MPS VII dogs (i.e., 0.48 versus greater than 2.5 mmol/l). In contrast, the thermo-, cryo-, and pH stability properties, as well as the pH optimum (approximately 4.6), were essentially unaffected. In addition, the canine MPS VII hepatic residual activity was unresponsive to sulfhydryl reducing reagents and divalent cations, despite the fact that incubation of normal canine beta-glucuronidase with dithiothreitol and magnesium and/or calcium enhanced the activity more than 15-fold.  相似文献   
119.
The binding properties of Pseudomonas aeruginosa agglutinin-I (PA-IL) with glycoproteins (gps) and polysaccharides were studied by both the biotin/avidin-mediated microtiter plate lectin-binding assay and the inhibition of agglutinin-glycan interaction with sugar ligands. Among 36 glycans tested for binding, PA-IL reacted best with two glycoproteins containing Galalpha1-->4Gal determinants and a human blood group ABO precursor equivalent gp, but this lectin reacted weakly or not at all with A and H active gps or sialylated gps. Among the mammalian disaccharides tested by the inhibition assay, the human blood group Pkactive Galalpha1-->4Gal, was the best. It was 7.4-fold less active than melibiose (Galalpha1-->6Glc). PA-IL has a preference for the alpha-anomer in decreasing order as follows: Galalpha1-->6 >Galalpha1-->4 >Galalpha1-->3. Of the monosaccharides studied, the phenylbeta derivatives of Gal were much better inhibitors than the methylbeta derivative, while only an insignificant difference was found between the Galalpha anomer of methyl- and p -NO2-phenyl derivatives. From these results, it can be concluded that the combining size of the agglutinin is as large as a disaccharide of the alpha-anomer of Gal at nonreducing end and most complementary to Galalpha1-->6Glc. As for the combining site of PA-IL toward the beta-anomer, the size is assumed to be less than that of Gal; carbon-6 in the pyranose form is essential, and hydrophobic interaction is important for binding.   相似文献   
120.
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