In Vitro Cytotoxicity of Mokko Lactone in Human Leukemia HL-60 Cells: Induction of Apoptotic Cell Death by Mitochondrial Membrane Potential Collapse

We studied the effect of mokko lactone (ML) isolated from the roots of Saussurea lappa (Compositae), a plant that is used for medicinal purposes in Korea, on the induction of apoptosis in human leukemia HL-60 cells. ML was cytotoxic to HL-60 cells, and this cytotoxic effect of ML appears to be attributable to its induction of apoptotic cell death, as ML induced nuclear morphologic changes and internucleosomal DNA fragmentation and increased the proportion of Annexin V-positive cells and the activity of caspase-3. Further studies revealed that the induction of apoptosis by ML was associated with the loss of mitochondrial membrane potential. Collectively, our results suggest that apoptosis induced by ML in HL-60 cells was executed by a collapse of mitochondrial membrane potential followed by the activation of caspase-3. This is the first report on the mechanism of apoptosis-inducing effect of ML.     

苦楝化学成份的研究

从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,¹HNMR,¹³CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。     

The alteration of enterochromaffin cell,mast cell,and lamina propria T lymphocyte numbers in irritable bowel syndrome and its relationship with psychological factors

Background/Aims: Psychological factors and subtle histopathological changes have been implicated in irritable bowel syndrome (IBS). The aims of the present study were to investigate whether the numbers of enterochromaffin (EC) cells, mast cells, and lamina propria T lymphocytes are altered in IBS, and evaluate the relationship of such alterations with psychological factors. Methods: Forty‐two consecutive IBS patients (M : F = 17:25, mean age 48 years) fulfilling the Rome III criteria and twelve asymptomatic healthy controls underwent rectal biopsy. Immunostaining was performed for EC cells, mast cells, and lamina propria T lymphocytes. Results: The IBS group included five post‐infectious (PI) IBS and 37 non‐PI IBS patients. Significantly more EC cells, mast cells and lamina propria T lymphocytes were observed in PI IBS patients. Mast cells significantly increased in non‐PI IBS‐D (diarrhea) patients, but not in non‐PI IBS‐C (constipation) and non‐PI IBS‐M (mixed) patients. Enterochromaffin cell numbers were not significantly altered in non‐PI IBS patients. Anxiety and depression scores did not differ between IBS patients with and without abnormal increase in EC cell or mast cell counts, defined as more than the mean of controls + 2 standard deviations. Enterochromaffin cell, mast cell, or lamina propria T lymphocyte numbers were poorly correlated with anxiety and depression scores in the IBS group. Conclusions: Enterochromaffin cells, mast cells, and lamina propria T lymphocytes significantly increase in PI IBS, whereas only mast cells significantly increase in non‐PI IBS‐D. Such histopathological changes do not seem to be directly associated with psychological factors.     

Pericardium Plug in the Repair of the Corneoscleral Fistula After Ahmed Glaucoma Valve Explantation

We report four cases in which a pericardium (Tutoplast®) plug was used to repair a corneoscleral fistula after Ahmed Glaucoma Valve (AGV) explantation. In four cases in which the AGV tube had been exposed, AGV explantation was performed using a pericardium (Tutoplast®) plug to seal the defect previously occupied by the tube. After debridement of the fistula, a piece of processed pericardium (Tutoplast®), measured 1 mm in width, was plugged into the fistula and secured with two interrupted 10-0 nylon sutures. To control intraocular pressure, a new AGV was implanted elsewhere in case 1, phaco-trabeculectomy was performed concurrently in case 2, cyclophotocoagulation was performed postoperatively in case 3 and anti-glaucomatous medication was added in case 4. No complication related to the fistula developed at the latest follow-up (range: 12~26 months). The pericardium (Tutoplast®) plug seems to be an effective method in the repair of corneoscleral fistulas resulting from explantation of glaucoma drainage implants.     

The effect of moesin overexpression on ageing of human dermal microvascular endothelial cells

Abstract:  Senescence of microvascular endothelial cells is known to play an important role in the pathophysiology of vascular diseases related to ageing, but the accurate mechanism or related genes are not known. Moesin, a cytoskeletal protein and the most potent candidate as an ageing-related protein, showed obvious changes in expression when compared before and after ageing. In this study, a lentivirus was used to overexpress moesin in endothelial cells. The expression of cell cycle mediators such as p16, cyclin D1 and cdk4, which can be the markers of ageing, was compared by RNA and was shown to be suppressed in moesin overexpressed endothelial cells. In conclusion, it can be said that the expression of moesin delays senescence of human dermal microvascular endothelial cells and this fundamental discovery can be used as a basis for understanding the mechanism of ageing and age-related diseases.     

Anopheles gambiae TRPA1 is a heat-activated channel expressed in thermosensitive sensilla of female antennae

Heat sensitivity is a sensory modality that plays a critical role in close-range host-seeking behaviors of adult female Anopheles gambiae , the principal Afrotropical vector for human malaria. An essential step in this activity is the ability to discriminate and respond to increases in environmental temperature gradients through the process of peripheral thermoreception. Here, we report on the characterization of the anopheline homolog of the transient receptor potential (TRP) A1/ANKTM1 channel that is consistent with its role as a heat-sensor in host-seeking adult female mosquitoes. We identify a set of distal antennal sensory structures that specifically respond to temperature gradients and express AgTRPA1 . Functional characterization of AgTRPA1 in Xenopus oocytes supports its role in the molecular transduction of temperature gradients in An. gambiae , providing a basis for targeting mosquito heat responses as a means toward reducing malaria transmission.