Most leukocytes can roll along the walls of venules at low shear stress (1 dyn/cm
2
), but neutrophils have the ability to roll at 10-fold higher shear stress in microvessels
in vivo
1
,
2
. The mechanisms involved in this shear-resistant rolling are known to involve cell flattening
3
and pulling of long membrane tethers at the rear
4
–
6
. Here, we show that these long tethers do not retract as postulated
6
,
7
, but instead persist and appear as ‘slings’ at the front of rolling cells. We demonstrate slings in a model of acute inflammation
in vivo
and on P-selectin
in vitro
, where P-selectin-glycoprotein-ligand-1 (PSGL-1) is presented as discrete sticky patches while LFA-1 is expressed over the entire length on slings. As neutrophils roll forward, slings wrap around the rolling cells and undergo a step-wise peeling from the P-selectin substrate enabled by the failure of PSGL-1 patches under hydrodynamic forces. The ‘step-wise peeling of slings’ is distinct from the ‘pulling of tethers’ reported previously
4
–
6
,
8
. Each sling effectively lays out a cell-autonomous adhesive substrate in front of neutrophils rolling at high shear stress during inflammation.
The results suggest that for definitive preemptive analgesia, blockade of opioid and N-methyl-d-aspartate receptors is necessary for upper abdominal surgery such as gastrectomy; singly, either treatment provided significant, but not definitive, postsurgical pain relief. Epidural morphine may affect the spinal cord segmentally, whereas intravenous ketamine may block brain stem sensitization via the vagus nerve during upper abdominal surgery.
Manuscript
2
AbsrtactThe marine red alga Porphyra yezoensis has been proposed as a model plant for physiological and genetic studies in seaweeds because of its biological and economical importance. However, the progress of molecular biological studies using gene transfection and genetic transformation systems has been hindered by difficulties in the expression of foreign genes in P. yezoensis cells. To overcome this situation, we developed a transient gene expression system to monitor gene expression in P. yezoensis cells. An artificial -glucuronidase (GUS) coding region was synthesized to adapt it to the codon usage of P. yezoensis (PyGUS) and then evaluated for efficiency as a reporter of transient gene expression by particle bombardment. We also demonstrated the importance of using the promoter of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene from P. yezoensis for efficient expression of PyGUS, because the cauliflower mosaic virus (CaMV) 35S promoter, which has been successfully used for monitoring gene expression in nuclei and chloroplasts of higher plants, was less active in P. yezoensis cells. Therefore, the lack of knowledge about differences in the regulatory machinery of gene expression between P. yezoensis and terrestrial plants seems to be why experimental systems for monitoring gene expression were previously not developed in P. yezoensis. Establishment of the transient gene expression system in P. yezoensis could facilitate biotechnological developments in this organism.3
Langerhans cells are MHC class II antigen-positive antigen-presenting cells in the epidermis. Recent studies have revealed that Langerhans cells express costimulatory molecules like B7-1 and B7-2 and the accessory molecule CD40. Although these molecules are important for the antigen-presenting function of Langerhans cells, little is known about the precise regulation of their expression on purified Langerhans cells. Using a panning technique, we purified epidermal Langerhans cells to around 95% purity. Freshly prepared Langerhans cells (fLC) expressed the mRNA for receptors for M-CSF (cfms), GM-CSF (GM-CSFR), and TNF-alpha (TNFRII). TNF-alpha markedly upregulated CD40 and B7-1 expression on Langerhans cells, but not B7-2 expression. GM-CSF moderately upregulated B7-1 and B7-2 expression, and slightly upregulated CD40 expression. M-CSF moderately upregulated B7-1 expression, but did not modulate CD40 or B7-2 expression. Dexamethasone (DEX) markedly inhibited CD40, B7-1, and B7-2 expression on Langerhans cells. Cyclosporin A (CsA) and FK506 slightly inhibited CD40 and B7-1 expression on Langerhans cells, but not B7-2. Furthermore, TNF-alpha restored the DEX-induced inhibition of CD40 expression on Langerhans cells, but not the inhibition of B7-1 or B7-2 expression. GM-CSF restored DEX-induced inhibition of CD40, B7-1, and B7-2 expression. M-CSF did not affect the DEX-induced inhibition of these molecule expressions. These data provide a better understanding of the role of selective cytokines and immunosupressive drugs in the modulation of the antigen-presenting capacity of Langerhans cells.
The authors demonstrated that orexin-A was more potent than orexin-B in producing alteration of cholinergic basal forebrain neuronal activity and that the cortical activation induced by the PPTg stimulation against isoflurane anesthesia may be mediated through the orexin-1 receptors in the basal forebrain.
The pathogenesis of holoprosencephaly is multifactorial, and blockage of Sonic hedgehog signaling is one of the most important causative factors in animal models and human cases. In this study, the authors analyzed facial anomalies of mouse embryos, which were cultured in vitro and exposed to cyclopamine, an alkaloid blocker of Sonic hedgehog signaling. When cultured with cyclopamine for embryonic day 8.5 to 10.5, the whole body size was smaller than normal, and the distance and angle between the nasal placodes were remarkably reduced. Extension of the cranial surface vessels also was noted. No cyclopia was observed. Migration of the cranial neural crest cells seemed to be intact. Expressions of Patched-1 and Gli-1, downstream genes of Sonic hedgehog signaling, also were down-regulated in in situ hybridization and real-time reverse transcriptase-polymerase chain reaction analyses. The authors consider that these facial anomalies represent milder phenotypes of holoprosencephaly.
We investigated genetic diversity in 10 strains of Porphyra yezoensis and related species, collected from Japan and Korea, in order to identify an appropriate crossing partner for use in various genetic analyses. Firstly, the phylogenetic relationships among the 10 strains were examined using SSU rDNA sequences. All five Japanese strains (TU-1, TU-2, TUH-25, JHS and JHU) and two of the Korean strains (KGJ and KPH) were identified as P. yezoensis while the other three Korean strains (KTY1, KTY2 and KTY3) were identified as P. tenera. Using cleaved amplified polymorphic sequence analysis, genetic polymorphisms lying in five regions of four genes (ß-tubulin, TOP2, EF-1 and V-ATPase) were examined. Twenty out of 34 restriction endonucleases revealed genetic polymorphisms between the seven strains of P. yezoensis and the three strains of P. tenera in all five regions tested. Furthermore, when they were employed to digest the fragments of TOP2 and V-ATPase, 14 enzymes discriminated the two Korean strains of P. yezoensis (KGJ and KPH) from the five Japanese strains of this species. The level of polymorphism was much higher in the amplified fragment of V-ATPase (including four introns) than in that of TOP2 without an intron. The gene regions with detected polymorphisms would be useful molecular markers for confirmation of cross-fertilization in sporophytic thalli and for construction of a linkage map. A suitable combination of the strains in the cross experiment is discussed.
Epidural preemptive analgesia was reliably effective in limb and breast surgeries but ineffective in abdominal surgery, suggesting involvement of the brainstem and cervical spinal cord via the vagus and phlenic nerves.
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