Environmental DNA monitoring method of the commercially important and endangered fish Gnathopogon caerulescens

Limnology - Gnathopogon caerulescens is an endangered but commercially important fish in Lake Biwa, Japan. The population size of G. caerulescens has drastically reduced in the past decades, and...     

Histological Observations on Initiation and Morphogenesis in Immature and Mature Embryo Derived Callus of Barley (Hordeum vulgare L.)

Callus was induced from immature and mature embryos of barley(cv. Haruna Nijo) on Murashige and Skoog medium containing 2mg l^-1 2,4-D and 5 mg l^-1 picloram, respectively. Paraffin sections(10 µm thick) were prepared for histology during callusinitiation and plant regeneration. Meristems were regeneratedfrom nodular compact callus (NC) derived from scutellar epidermisin immature embryos, whereas they were regenerated from NC derivedfrom epidermal cells of leaf or coleoptile bases in mature embryos.Regardless of the explant source, regeneration was predominantlythrough organogenesis, although regeneration through somaticembryogenesis infrequently occurred. Thus, the callus inducedfrom immature and mature embryos of barley was regarded as 'nodularcompact' rather than 'embryogenic'.Copyright 1995, 1999 AcademicPress Barley, callus, Hordeum vulgare, histology, immature embryo, mature embryo, regeneration     

Human Pancreatic Tumor Organoids Reveal Loss of Stem Cell Niche Factor Dependence during Disease Progression

1. Download high-res image (219KB)
2. Download full-size image

     

Decreased apoptosis of beta 2- integrin-deficient bovine neutrophils

Stimulant-induced viability of neutrophils, nuclear-fragmentation, increase in intracellular calcium ([Ca2+]i), expression of annexin V on neutrophils and proteolysis of a fluorogenic peptide substrate Ac-DEVD-MCA (acetyl Asp-Glu-Val-Asp alpha-[4-methyl-coumaryl-7-amide]) by neutrophil lysates from five normal calves and three calves with leucocyte adhesion deficiency were determined to evaluate the apoptosis of normal and CD18-deficient neutrophils. Viability was markedly decreased in control neutrophils stimulated with opsonized zymosan (OPZ), compared to CD18-deficient neutrophils at 37 degrees C after incubation periods of 6 and 24 hours. The rate of apoptosis of control neutrophils stimulated with OPZ increased significantly depending on the incubation time, whereas no apparent increase in apoptosis was found in CD18-deficient neutrophils under the same conditions. Aggregated bovine (Agg) IgG-induced apoptosis of control neutrophils was not significantly different from that of CD18-deficient neutrophils. The expression of annexin V on OPZ-stimulated control neutrophils was greater than that of unstimulated ones 6 h after stimulation. No apparent increase in annexin V expression on CD18-deficient neutrophils was found with OPZ stimulation. A delay in apoptosis was demonstrated in CD18-deficient bovine neutrophils and this appeared to be closely associated with lowered signalling via [Ca2+]i, diminished annexin V expression on the cell surface, and decreased caspase 3 activity in lysates.     

Anti‐inflammatory effects of activated protein C on human dendritic cells

Activated protein C (APC) has an anticoagulant action and plays an important role in blood coagulation homeostasis. In addition to its anticoagulant action, APC is known to have cytoprotective effects, such as anti‐apoptotic action and endothelial barrier protection, on vascular endothelial cells and monocytes. However, the effects of APC on DCs have not been clarified. To investigate the effects of APC on human DCs, monocytes were isolated from peripheral blood and DC differentiation induced with LPS. APC significantly inhibited the production of inflammatory cytokines TNF‐α and IL‐6 during differentiation of immature DCs to mature DCs, but did not inhibit the production of IL‐12 and anti‐inflammatory cytokine IL‐10. Interestingly, treatment with 5 μg/mL, but not 25 μg/mL, of APC significantly enhanced production of IL‐10. In addition, protein C, which is the zymogen of APC, did not affect production of these cytokines. On the other hand, flow cytometric analysis of DC's surface molecules indicated that APC does not significantly affect expression of CD83, a marker of mDC differentiation, and the co‐stimulatory molecules CD40, CD80 and CD86. These results suggest that APC has anti‐inflammatory effects on human DCs and may be effective against some inflammatory diseases in which the pathogenesis involves TNF‐α and/or IL‐6 production.     

Toll-like receptor 3 contributes to spinal glial activation and tactile allodynia after nerve injury

Toll-like receptors (TLRs) play an essential role in innate immune responses and in the initiation of adaptive immune responses. Microglia, the resident innate immune cells in the CNS, express TLRs. In this study, we show that TLR3 is crucial for spinal cord glial activation and tactile allodynia after peripheral nerve injury. Intrathecal administration of TLR3 antisense oligodeoxynucleotide suppressed nerve injury-induced tactile allodynia, and decreased the phosphorylation of p38 mitogen-activated protein kinase, but not extracellular signal-regulated protein kinases 1/2, in spinal glial cells. Antisense knockdown of TLR3 also attenuated the activation of spinal microglia, but not astrocytes, caused by nerve injury. Furthermore, down-regulation of TLR3 inhibited nerve injury-induced up-regulation of spinal pro-inflammatory cytokines, such as interleukin-1β, interleukin-6, and tumor necrosis factor-α. Conversely, intrathecal injection of the TLR3 agonist polyinosine–polycytidylic acid induced behavioral, morphological, and biochemical changes similar to those observed after nerve injury. Indeed, TLR3-deficient mice did not develop tactile allodynia after nerve injury or polyinosine–polycytidylic acid injection. Our results indicate that TLR3 has a substantial role in the activation of spinal glial cells and the development of tactile allodynia after nerve injury. Thus, blocking TLR3 in the spinal glial cells might provide a fruitful strategy for treating neuropathic pain.     

Horse domestication and conservation genetics of Przewalski's horse inferred from sex chromosomal and autosomal sequences

Despite their ability to interbreed and produce fertile offspring,there is continued disagreement about the genetic relationshipof the domestic horse (Equus caballus) to its endangered wildrelative, Przewalski's horse (Equus przewalskii). Analyses havediffered as to whether or not Przewalski's horse is placed phylogeneticallyas a separate sister group to domestic horses. Because Przewalski'shorse and domestic horse are so closely related, genetic datacan also be used to infer domestication-specific differencesbetween the two. To investigate the genetic relationship ofPrzewalski's horse to the domestic horse and to address whetherevolution of the domestic horse is driven by males or females,five homologous introns (a total of 3 kb) were sequenced onthe X and Y chromosomes in two Przewalski's horses and threebreeds of domestic horses: Arabian horse, Mongolian domestichorse, and Dartmoor pony. Five autosomal introns (a total of6 kb) were sequenced for these horses as well. The sequencesof sex chromosomal and autosomal introns were used to determinenucleotide diversity and the forces driving evolution in thesespecies. As a result, X chromosomal and autosomal data do notplace Przewalski's horses in a separate clade within phylogenetictrees for horses, suggesting a close relationship between domesticand Przewalski's horses. It was also found that there was alack of nucleotide diversity on the Y chromosome and highernucleotide diversity than expected on the X chromosome in domestichorses as compared with the Y chromosome and autosomes. Thissupports the hypothesis that very few male horses along withnumerous female horses founded the various domestic horse breeds.Patterns of nucleotide diversity among different types of chromosomeswere distinct for Przewalski's in contrast to domestic horses,supporting unique evolutionary histories of the two species.