This study explores the histological features and Bmp4 expression patterns in the replaced tooth germ of Xenopus laevis . Tooth germ formation starts from the dental placode through epithelial-mesenchymal interactions, involving various signaling pathways such as Fgf, Shh, Bmp, and Wnt. In mice, Bmp4 expression in the dental placode inhibits Pax9 expression in the dental mesenchyme. Although absent in the presumptive dental lamina of birds and toothless mammals, Bmp4 remains conserved in reptiles and fish owing to gene duplication. However, its expression in amphibian tooth germs is poorly understood. Three-month-old X. laevis were employed in this study. Initially, samples underwent paraffin embedding and were sectioned into 5 or 12 μm ribbons for H&E staining and in situ hybridization, respectively. Results revealed teeth appearing in two maxillary rows: the labial side, with prefunctional and functional teeth, and the lingual side, with replaced tooth germs behind functional teeth. Enameloid was observed between the inner dental epithelium and dental mesenchyme at the cap or early bell stages, whereas enamel and dentin formed during the late bell or mineralization stages from the replaced tooth germ. Bmp4 expression was evident in the inner dental epithelium (ameloblasts), dental papilla (odontoblasts), stellate reticulum, and Hertwig’s epithelial root sheath. Overall, these findings highlight the conservation of Bmp4 expression in X. laevis tooth development.
This study evaluated the risk of single and combined exposure to microplastics in zebrafish (Danio rerio) through biomarkers, such as survival rate, excretion rate, and histological alterations of organ systems. The experimental groups were the control (Cont.), single microplastics exposure group (MPs, 1.83%/fish total weight (g)), the copper group (Cu, 21.6 μg L-1), and a group with combined exposure to MPs and copper (MPs*Cu). The experiment was conducted with individual exposure (7 days) for MP excretion rate analysis and group exposure (14 days) for biomarker analysis. The daily excretion rate of MPs tended to decrease in a time-dependent manner. The copper concentration in the body was not significantly different between single and combined copper exposure. The degeneration of mucous cells in the skin, capillary dilation of the gill lamella, increased intestinal mucous, hepatocyte hypertrophy, and the degeneration of glomeruli and renal tubules were observed in all exposure groups. These histological alterations showed the highest tendency in the MPs*Cu group. In this study, the changes in biomarkers were attributed to the single effect of copper or the combined effect of copper and MPs rather than being solely influenced by MPs.
연구는 갈치 Trichiurus lepturus의 성 성숙과 생식생물학적 기초 정보를 제공하기 위해 수행하 였다. 난자형성과정 동안 난모세포와 핵의 크기는 증가하였으나 핵에 대한 인의 비율은 감소 하였다. H-E 염색 결과, 세포질의 염색성은 호염기성에서 호산성으로 변하였다. 난황형성개시 기 난모세포의 난경은 약 63.2 (±12.7) μm였다. 세포질에서는 호산성의 난황핵이 관찰되었다. 성숙기 난모세포의 난경은 216.6 (±24.7) μm였으며, GVBD (germinal vesicle breakdown)가 관 찰되었다. 완숙기 난모세포의 난경은 317.9 (±80.9) μm였으며, 방사대의 두께는 4.2 (±1.7) μm 였다. 난모세포의 발달형태는 난군동기발달형에 속하며, 난황 축적은 대부분의 경골어류와 마 찬가지로 외재적 방법과 내재적 방법에 의한 것으로 판단되었다.
The bean bug, Riptortus pedestris, is one of major hemipteran pests against the soybean, Glycine max in Korea. In previous study, it was suggested that water-taking in the first instar nymphal stage of R. pedestris is certainly necessary for successful ecdysis and their survival. To investigate water-taking behavior of the first instar nymphs of R. pedestris on plant, electrical penetration graphic patterns were analysed while R. pedestris fed on the napa cabbage leaf, Brassica rapa subsp. pekinensis by using EPG system. In the result, a X-waveform was dominantly observed for average 42.0 min out of total recording time (120 min). There was significant positive correlation (r = 0.457, P = 0.000452, n = 55) between body weight increase and cumulative durations of X-waveform. In addition, histological observation of cross-sections indicated that stylet tip in the plant tissue during X-waveform period is located nearby xylem cells, suggesting that X-waveform is closely related to xylem sap feeding behavior of R. pedestris in plant.
A 57 years old female complained of severe pain on the right temporomandibular joint (TMJ) area. Her right condyle had been partly resected under surgical operation 13 years ago due to condyle hypertrophy, thereafter she felt dull pain on TMJ area and recently the lesion became severely swelled and painful leading to cancer phobia. The present radiological views showed slightly enlarged and sclerosed condyle with increased radiopacity, but its articular sliding function was almost disable during mouth opening. The patient’s TMJ lesion was carefully managed with conservative physiotherapy and pain treatment. The microsection of condyle head obtained from the previous operation was re-evaluated histologically, and it was finally diagnosed as osteochondrosis dissecans (OCD), exhibiting hyperplastic proliferation of cartilage in condyle head and marked vascular dilatation in epiphyseal zone. This abnormal cartilage tissue was distinguishable from normal cartilage tissue found in the peripheral cartilaginous cap of the same microsection. The involved cartilage cap showed thick hypertrophic chondrocyte zone with horizontal and vertical clefts accompanying diffuse hyaline degeneration. The superficial fibrous zone of cartilage cap was thickened and frequently peeled off, while lower hypertrophic zone of cartilage cap was highly cellular and proliferative. Consequently, the endochondral ossification became aberrant and resulted pre-mature apoptosis of many hypertrophic chondrocytes, followed by diffuse and mild inflammatory reaction in the underlying marrow tissue. Therefore, it was suggested that this hypertrophic condyle lesion, OCD, be differentiated depending on radiological and histological features from ordinary condyle hyperplasia, osteochondroma, and osteoarthritis, and that the pathological confirmation of OCD may provide a reliable modality for dental and medical treatment of chronic and painful TMJ lesion.
A saccular aneurysm is a localized, pouch arterial abnormality, Varous kinds of experimental saccular aneurysm models have been developed to treat aneurysms, and more effective ways to create aneurysm model is also needed. This study aims to compare aneurysm models induced by either porcine pancreatic elastase or papain from papaya latex. Eleven New Zealand white rabbits were divided into three treatment groups: normal saline (n=3), papain (n=4), and elastase (n=4). The right common carotid artery was selected as the aneurysmal site, and the respective substance was incubated for 20 minutes. No neurological signs occurred after operation. Hematoxylin-eosin (H&E) staining and modified elastic trichrome stain were performed 2 weeks after the procedure for pathological analysis. Histological findings for the control group showed normal vascular wall structure, normal elastic fiber, and no signs of inflammation. In samples of the papain group, the vascular walls were damaged and the endothelium was detached. Most of the elastic fibers were destructed. All samples of the papain group showed elastic fragmentation. In the elastase group, all samples showed severe inflammation and destruction of the vascular structure. There was also an elastase-induced sterile abscess. These findings indicate that elastase does not induce stable aneurysms at a dose of 1 mg because of excessive inflammation and destruction of the vascular structure. Elastase induces inflammation and apoptosis which results in the vascular wall to weaken before an aneurysm is formed. Papain at the dose of 1 mg, in contrast, seems to be a suitable candidate for enzymatic aneurysm models in the rabbit.
To elucidate the effect of cellular phone electromagnetic wave (EMW) exposure on the developing cerebellar cortex of neonatal Sprague-Dawley rats, animals were exposed to cellular phone electromagnetic waves for 1 hr per day for 3 weeks. At the end of the experimental period, animals were sacrificed by cardiac perfusion, after which histological samples were prepared and observed microscopically. In the EMW exposure group, external granule cells were remained partially in the external granular layer without migrating into the internal granular layer. In addition, dark stained shrunken Purkinje cells with pyknotic nuclei increased and the outline of cells became irregular and showed degenerative signs, such as mitochondrial swelling and disrupted cristae. Moreover, the cisternae of rough endoplasmic reticula and Golgi complex were severely swollen. Bergmann glial cells adjacent to the dark stained Purkinje cells were swollen and cytoplasmic organelles were scant. Dark stained shrunken granule cells were also observed and the outline of cells was irregular. The results of the present study suggest that cellular phone EMW exposure to neonatal Sprague-Dawley rats leads to a partial delay of early migration of cerebellar cortical cells and degenerative changes in Purkinje cells, Bergmann glial cells and granule cells.
This study is for the consideration of the existence tendency of Kudoa septempunctata in olive flounder. In general, muscle has shown a strong PCR positive reaction in spores containing tissues rather than non-containing tissues. However, blood PCR results showed opposed tendency. In various organs of the tested fish containing spores in muscle tissue, heart had shown positive reaction along with muscle at PCR analysis. Muscle fiber necrosis was observed at the histological observation, and this degeneration was common in both samples. The one sample was the PCR positive muscle containing spore and the other was the PCR positive muscle non-containing spore. Both of muscle tissues indicated a positive reaction at ISH (in-situ hybridization) against K. septempunctata.
This study investigated the stress-related metabolites and hormones in blood and compared the muscle structure to identify the reason for blood splash in Hanwoo beef. Five slaughter houses were selected based on the region (Seoul, Gimhae, Jungbu, Naju, and Goryung) and a previous blood splash record. In total, three-hundred eighty blood samples (n=380) and forty-two muscle tissues (n=42) of control and blood splash Hanwoo beef were collected during the slaughter process and beef grading. Blood metabolites were analyzed including glucose, lactate, creatinine, urea-N, and hormones such as cortisol and thyroxin. Muscle fiber, fiber bundle, and capillary wall thickness were measured under microscope. The concentrations of blood glucose, lactate, and urea-N were not significantly different between the control and the blood splash samples. Cortisol and thyroxin levels were not significantly different in both samples. In contrast, the creatinine level was significantly increased (p<0.05) in the blood splash samples. There were also no significant differences observed in muscle fiber, bundles, and capillary wall thickness between the control and the blood splash tissues. In conclusion, blood metabolites, hormones, and muscle fiber showed no differences between the control and the blood splash animal. However, increased creatinine levels may be used as an indicator for identifying blood splash prior to slaughter in Hanwoo.
With the multiple practices of bone graft using different artificial bone regenerative substitutes, the bone graft procedures have been widely performed to increase the bony stabilization of dental implant. Xenogenic bone graft materials have been well developed because of their good biocompatibility and abundant source of bone materials. The present study demonstrated the histological findings from excellent bony remodeling in xenogenic bone graft biopsies compared to those findings in autogenous bone graft. For the graft bone biopsies which were usually done in 5-9 months after graft bone insertion, five types of histological grades including excellent, favorable, partial, degenerative, and poor bony remodeling could be assessed to give prognostic information for dental implant. However, recently the xenograft bone materials have been much improved and produced strong osteogenic effect. Among 239 cases of trephine bur-supported core bone biopsy the excellent bony remodeling was found in 20 cases (13.1%) out of 153 xenogenic bone grafts and in 13 cases (43.3%) out of 30 autogenous bone grafts. They produced abundant new bones on the surface of the graft bones in 5–9 months, and the graft bones were partly resorbed and also surrounded by the repetitive deposition of new bone. The osteophytic new bones showed strong birefringence under polarizing microscope, and were gradually elongated and anastomosed with each other to form trabecular bony networks which became proper stress-baring structures for dental implant. Their marrow stromal tissues were composed of loose connective tissue which was well vascularized but rarely infiltrated with inflammatory cells. The present study compared the histological features of excellent bony remodeling between xenogenic and autogenous bone grafts. Although the ratio of excellent bony remodeling in xenogenic bone graft was still low, 13.1%, the recent advance of xenogeic bone products was remarkable in biological aspect and almost comparable to the autogenous bones. Therefore, it was suggested that the xenogenic bone graft will be applicable to the bone regeneration procedures for dental implant with beneficial output in the near future.
The purpose of the study was to investigate effects of Low intensity cardiac rehabilitation, using a treadmill, on the myocardial structure. We identified the effects by analyzing changes in the rats' weights and the results of biopsies. Twenty Sprague-Dawley male rats, 50 weeks old, were randomly divided into the exercise group and the control group. myocardial infarction( MI) was induced by ligaturing their left anterior descending artery. After the acute MI induction, two rats of each group began to fall dead, therefore, eight of each group completed at the end of the experiment. We used treadmills for animals for the exercise group. This exercise group performed 30 minutes of exercise five times per week for six weeks, while the control group did not perform any exercise. No statistically significant differences in weight were found in within group comparison and between group comparison. Furthermore, we observed histological changes in the myocardium using Hematoxylin & Eosin and Masson's trichrome staining in both groups. Low-intensity exercise inhibited myocardial fibrosis, may serve as a reference in the cardiopulmonary field, which plays a role in rehabilitating patients with cardiac disorders, including acute MI.