Pathological changes and functional reconstruction of radiation-induced salivary glands repaired by stem cells and biomaterials / 中国组织工程研究

BACKGROUND: Radiation therapy is currently one of the main treatments for head and neck cancer. Radiation therapy can kill cancer cells, but it can also damage normal cells or tissues. OBJECTIVE: To summarize the research progress of the changed structure of radioactive salivary glands and repair in recent years. METHODS: PubMed database, Wanfang database and China Full-Text Journal Database were searched. The search terms were “salivary glands; radiation injury; histological change; cell therapy” in English and Chinese. The time range was from 1991 to 2020. By reading the title, abstract and full text, repetitive studies were excluded. Finally, 57 articles were summarized. RESULTS AND CONCLUSION: In the treatment of head and neck cancer patients, xerostomia caused by radioactive damage to salivary gland tissue is its typical chronic side effect. At present, it is believed that radiation will mainly affect the structure of salivary gland tissues and lead to the decline of its function, including changes in the structure of salivary glands and ducts, as well as changes in saliva secretion and excretion after blood vessel and nerve injury. However, the mechanism of radiation damage has not been pointed out. Studies have shown that stem cells derived from fat, bone marrow and human amniotic membrane epithelium can treat radiation-induced salivary gland damage, improve salivary secretion, and the transplanted cells can form secretory alveoli and duct structures in the body.

Histological changes of cornea in vivo of patients with xerophthalmia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the changes of corneal cytology of patients with different degrees of xerophthalmia of the types of deficient aqueous production and over evaporation with confocal microscopy. METHODS:Retrospective case series was adopted with three - dimensional corneal topography and anterior segment analysis system (Sirius system). A total of 33 typical dry eye patients (total 65 eyes) with deficient aqueous production and 28 typical dry eye patients (total 55 eyes) with over evaporation were selected from optical center of the First Affiliated Hospital of Harbin Medical University from December 2016 to June 2017, which were grading according to dry eye degrees. The corneal epithelial cell (surface epithelial cell, pterygoid epithelial cell, basal epithelial cell), Langerhans cell (dendritic cell),stroma (deep stromal layer and superficial stromal layer), the density and form of endothelial cells were observed and analyzed with the confocal microscope. RESULTS: Confocal microscope showed that the number of corneal epithelial cells decreased with the increasing of dry eye severity in patients with tear deficiency and evaporative. The results were statistically significant (P<0.01). The sizes of each layer of corneal epithelium cells were uneven, and the arrangement was irregular. The diameter of corneal sub-epithelial nerve fiber of deficient aqueous production dry eye became thinner with irregular arrangement. With the increase in severity of dry eye,the degree of curvature and branches gradually increased. The activation degree of Langerhans cells of evaporative dry eye was directly proportional to the severity of dry eye(P<0 01). There was no significant changes in the number of superficial stromal cells in the two types of dry eye (P>0 05). The number of deep stromal cells in the two types of dry eye had no relations with the severity of dry eye (P>0. 05). There was no significant changes in the number of corneal endothelial cells in the two types of dry eye (P>0.05). CONCLUSION:The Sirius system can be used for non-contact and non-invasive examination and classification. And there is changes of the density and morphology in each layers of cornea cells of two types of dry eye with the confocal microscope.

Change of matrix metalloproteinase-9 in rats with multiple organ dysfunction syndrome / 中华急诊医学杂志

Objective To investigate the changes in the serum MMP-9 (matrix metalloproteinase-9) and the expressions of MMP-9 in lung, kidney and intestine in rats with multiple organ dysfunction syndrome (MODS) and confirm extracellular matrix injuries being the mechanism in MODS in order to propose a novel theoretical basis for cfinical treatment of MODS. Method Forty wister rats were randomly divided into two groups: control group (n=8) and MODS model group (n=32). The rats of model group were further divided into four subgroups ac-cordingto the time elapsed after modelling: 12 h (n=8), 24 h(n=8) ,48 h(n=8) and 72 h (n=8), and were modelled by celiac injection of mixed liquid of zymosan-paraffin (4 mL/100 g) after blood loss (1mL/100 g) by extirpating their left eyes. Blood,lung, kidney and intestine were sampled 12,24,48 and 72 hours after models were established. The histological changes in the lung, kidney and intestine of the rats were observed by light mi-croscope. The serum MMP-9 were measured by enzyme-linked immunosorbent assay (ELISA). The immunohisto-chemistry was used to observe the expression of MMP-9 in lung,kidney and intestine during different phases of MODS. The data were processed by one-way ANOVA and Bivariate analysis. Results Compared with control group, the organs were injured by congestion, edema and inflammatory cells infiltration to a certain extent in model groups. The serum MMP-9 increased markedly 12 hours after modelling (P<0.01 ) and peaked 48 hours later. The expressions of MMP-9 in lung, kidney and small intestine significantly increased from 12 h to 72 h after mod-elling (P<0.01 or 0.05). Conclusions The MMP-9 increased both in serum and tissue are closely associated with the pathological process of MODS. The mechanism of organ damage probably attributes to the damage of extra-celluar matrix and tissue construction.

An Intracerebral Hemorrhage Model Established by Autologous Blood Injection Three Times in Rat / 中国康复理论与实践

@#ObjectiveTo establish an animal model of intracerebral hemorrhage (ICH) in rat and to observe the changes in behavior, brain edema and tissue structure during absorption of the hematoma.MethodsAn animal model of ICH was established by stereotactically infusing 100 μl (the first time 20 μl, the second time 40 μl, the third time 40 μl) of autologous caudal artery blood into caudate nucleus in the rats. The behavior of rats with ICH was assessed by Bederson score, beam-walking test, bilateral forepaws grasp and measurement of forelimb placing. The brain edema and the change in histology were observed.ResultsThe successful ratio of this model was 75%. There were significant behavioral changes and brain edema at 6 h after the ICH in rats of the experimental group compared to those of the control group. The worse behavioral changes and brain edema was at 48～72 h after hemorrhage. In the earlier period, the nerve cells were swelling. A lot of glial cells appeared around the hematoma in the late period.ConclusionThis ICH model is reproducible, and the obvious behavioral change and histological changes are similar to clinical patient with ICH.

Histological and clinical study of artificial dermis implantation for restoration of soft tissue defects

The present study was aimed to compare the resorption rate and the histological change of the autogenous dermis and the artificial dermis (Terudermis(R).) after the transplantation, and to report the clinical results of the use of Terudermis(R). in order to restore the soft tissue defect. Twenty mature rabbits, weighing about 2 kg, were used for the experimental study. The autogenous dermis and the Terudermis(R). size 1 x 1 cm were transplanted to the space between the external abdominal oblique muscle and the external abdominal oblique fascia of the each rabbits. They were divided into 4 groups (n=5 each) and gathered at 1, 2, 4, and 8 weeks after the transplantation. The resorption rate was calculated, and H-E stain was preformed to observe the histological changes. The chart review of the 17 patients who received Terudermis(R). graft to the facial soft tissue defects was conducted for the clinical study. The resorption rate at 8 weeks after the transplantation was 21.5% for the autogenous dermis, and 36.4% Terudermis(R). In microscopic examinations, the infiltration of the inflammatory cells and the epidermal inclusion cyst were observed in the autogenous dermis graft. The neovascularization and the progressive growth of the new fibroblast were shown in the Terudermis(R). graft. In clinical data of 17 patients, the size of the grafted Terudermis(R). was from 1.5 cm2 to 7.5 cm2 (average 3.5 cm2). Follow-up ranged from 5 to 25 months. Fourteen patients with cleft palate demonstrated stability of the graft and unremarkable complications. But unstability of the graft and the partial relapse were observed in three patients received the vestibuloplasty. These results indicate that Terudermis(R). can be available substitute of autogenous dermis because of the stability about resorption, the histocompatibility, and the unremarkable clinical complications.

Histological Changes after Intradiscal Steroid Injection to the Intervertebral Disc in Disc Injury Rabbit Model

OBJECTIVE: To evaluate the degeneration changes of disc injury rabbit model produced by needle puncture to intervertebral disc and to observe the histological changes of the degenerated disc treated with intradiscal steroid. METHOD: The subjects were composed of 10 L4-5 intervertebral discs (study group) and 10 L3-4 intervertebral discs (control group) of Newzealand white rabbits. The rabbits' discs were exposed by anterior approach and degeneration was elicited by 21 G needle puncture. After 4 weeks, the study group was injected with 0.2 ml triamcinolone acetonide (Tamcetone 40 mg/ml) and the control group was injected with 0.2 ml normal saline, intradiscally. The discs were extracted on 4 weeks after degeneration and stained with Hematoxylin-Eosin and investigated by light microscopy. RESULTS: Degenerative changes, including fissuring and focal fibrosis, were elicited in the all groups, but there were no significant histological differences between the two groups. CONCLUSION: We concluded that the degenerative changes are well observed in disc injury rabbit model. The mollification of discogenic pain following intradiscal steroid injection in practice may not be explained from light microscopic histological changes of the disc. Further biochemical or electromicroscopic study will be necessary to clarify the mechanism of alleviation of discogenic pain by intradiscal steroid.

Histological Changes In The Elongated Bone Affected By Osteodistraction Of The Mandible In The Dog

PURPOSE: Traditionally, the treatement of choice has been a bone grafting procedure to increase the length of bone in case of actual length discrepancy. But, bone grafting procedure has many disadvantages, for example, graft resorption, donor site morbidity, and so on. So, many trials have been performed to avert the use of autogenous bone graft via introducing new materials or methods. And, one of those trials has been realized by the development of a technique inducing bone lengthening by osteotomy (or corticotomy) and slow gradual distraction of the osteotomized segments. This new technique of bone lengthening dates back to the early 20th century. But, the majority of information concerning the biology of new bone formation during bone lengthening and technical details of the procedure were produced by extensive clinical and experimental studies performed by Ilizarov, a Russian surgeon. According to Ilizarov, with adequate blood supply, preservation of periosteum, rigid fixation of the osteotomized segments, and proper rate and rhythm of distraction, intramembranous bone rapidly develops within the distraction gap in the limb lengthening procedure. In the limb lengthening, many orthopedic surgeons try to observe the biologic and clinical principles recommended by Ilizarov. In the oral and maxillofacial region, however, not a few studies must be performed to apply this surgical technique in the clinical cases. Besides, the mechanism of bone formation in the distraction gap is not clear, yet. The purpose of this experiment was to scrutinize seriallly the histological changes in the elongated bone affected by osteodistraction of the mandibular body in an adult canine model. In addition, it was performed to confirm the presence of specific region(s) which was important in the bone formation in the gap through the observation of the expression pattern of osteocalcin and osteonectin with the immunohistochemical examination. MATERIALS AND METHODS: The experimental and control specimens were obtained from seven adult male mongrel dogs weighing over 20kg. The distractors were custom-made linear extraoral devices and bicortical fixation screws were 2.3mm in diameter, 50mm in total length, 15mm in screw length. The distractors were devised to produce a linear gap of 0.75mm between two bony segments every 360.turn of the rotation rod of the device. The mandibular body of the right side of each animal was corticotomized perpendicular to the occlusal plane and then two bony segments were separated completely by careful manipulation of the segments with bone forceps. The left side of each animal was left intact. This side was served as control. At sixth day after osteotomy and fixation of the segments were performed, distraction of the segments was commenced with a rate of 1.1mm/day and a rhythm of two/day for ensuing 7 days. the animals were euthanized at the 16th. 29th, and 44th day after the osteotomy. The bony specimens were decalcified, embedded in paraffin, sectioned 5micrometerthick and stained with H&E. The prepared specimens were examined under the light microscope. And, immunohistochemical examinations using anti-osteocalcin antibody (OC1, Biodesign, USA) and anti-osteonectin antibody Haematologic Technologies Inc., Essex, VT) to locate the expressions of osteocalcin and osteonectin, respectively, were performed. RESULTS: 1. New bone was observed already at the 16th. day after osteotomy. This suggests that new bone formation in osteodistraction was commenced at an early stage of the regenerative process. But, radiologically and microscopically, bony union was not completed in the distraction gap at the 44th. day after osteotomy. Therefore, rigid fixation must be maintained between the bony fragments till the complete bony union is confirmed clinically rather than one month or so after the completion of distraction. 2. Intramembranous bone formation predominated the regenerative process in the distraction gap. Some of the regenerated bone, however, was formed by endochondral ossification. 3. Focal islands of cartilage were observed at all experimental periods. 4. Considering the expression pattern of osteocalcin and osteonectin, new bone formation was considered to be commenced at the region adjacent to the central fibrous zone and therefore this region, especially the periosteum of this region, was important in regeneration of the distraction gap. Focus needs be set on the region adjacent to the CFZ and the role of periosteum in performing further experiments to elucidate the mechanism of bone formation in the distraction gap.

Histological Changes of the Intervertebral Disc with Intradiscal Steroid Injection

OBJECTIVE: To observe histological changes of the intervertebral disc injected with intradiscal steroid and mollification of discogenic pain. METHOD: A study group of 25 Sprague-Dawely rats was divided into five subgroups. A control group of 10 Sprague-Dawely rats was divided into five subgroups. The rats' intervertebral discs were exposed by an anterior surgical approach. For study group, the rats were injected intradiscally methylprednisolone acetate 4 mg (Depomedrol, 40 mg/ml) to the L4-L5 intervertebral disc, methylprednisolone sodium succinate 4 mg (Solumedrol, 40 mg/ml) to the L5-L6 intervertebral disc, and triamcinolone acetonide 4 mg (Triamcinolone, 40 mg/ml) to the L6-S1 intervertebral disc. For control group, the rats were injected intradiscally 0.1 ml of saline to the L5-L6 intervertebral disc and a needle was inserted in the L6-S1 intervertebral disc. The intervertebral discs were extracted after 1 week, 2 weeks, 3 weeks, 4 weeks, and 16 weeks. The extracted intervertebral discs were stained with Hematoxylin-Eosin and examined histomorphometrically. RESULTS: There is no significant histological change in either group until 4 weeks after the different types of steroid were injected. Focal fibrotic change was present in the Solumedrol and Triamcinolone injection subgroups after 16 weeks. CONCLUSION: We concluded that rapid mollification of discogenic pain following intradiscal steroid injection may not result from histological change of the disc. Further biochemical study will be neccessary to clarify mollification mechanism of discogenic pain by intradiscal steroid injection.

Histological studies of surgically resected hepatocellular carcinoma following combined radiotherapy and hyperthermia

Four cases of hepatocellular carcinoma (HCC) were surgically resected following combined radiotherapy (RT) and hyperthermia (HT). Complete necrosis of the tumor without viable tumor cell was found in one case and extensive tumor necrosis was observed in the other three cases; the percentage of necrosis in the specimens were 40%, 70%, and 80%, respectively. Histologic assessment showed mainly coagulative necrosis in the tumor with focal liquefactive necrosis. Cystic dilatation of sinusoids was observed in both tumor and nontumorous normal liver tissue. Other changes in normal liver tissue were unremarkable except for infiltration of inflammatory cells, fatty change, and proliferation of the bile ducts which can usually be seen beyond the area where any space occupying lesions are present. It is concluded that combined radiotherapy and hyperthermia can significantly induce coagulative necrosis of hepatocellular carcinoma with nonsignificant minimal histologic changes in adjacent nontumorous liver tissue.

Neurophysiologic - Histological Changes Following Injection of Morphine , Meperidine , Pentazocine on Sciatic Nerve of Dogs / 대한마취과학회지

The authors have already reported good local anesthetic effects of meperidine and pentazocine clinically in patients scheduled for various surgeries, followed by experimental evaluation of toxic effects of two drugs on the sciatic nerve of rats. Intraspinal (spinal, epidural) morphine as well as other narcotics administration has been widely used and well established for pain control. The action mechanism of intraspinal narcotics has been well defined, and meperidine and Pentazocine have been reported to be used as a sole agent for spinal anesthesia. We assurned that the action mechanism of subarachoid meperidine or pentazocine might be different to some extent from that of morphine. This investigation was primarily undertaken to examine the difference in action between meperidine and morphine and also to evaluate neurotoxic effects on sciatic nerve of dogs. Adult Korean dogs were chosen as exoerunebtak abunaks because it is easy to observe physiologic activity with responses and to avoid of manipulating trauma. The dogs were intubated and anesthetised with halothane and nitrous oxide. The sciatic nerve of the dogs was exposed and stimulated by a nerve stimulator to observe myoneural response and then injectied with 1% morphine 0.5 mg (Group 1), 5% meperidine 25 mg (Group 2) and 3% pentazocine 15 mg (Group 3). The dog was carefully observed in recovery room to see the myoneural activity After 1 week, 1 month or 2 months of careful observation, a specimen was taken under reanesthesia at 1 week, 1 month and 2 months after the careful obaervation, When the sciatic nerve was stimulated by a nerve stimulator, the normal muscle twitch was observed clearly in Group 1 with themorphine injection but was not observed in Group 2 with meperidine and Group 3 with pentazocine injection. Complete motor paralysis was noticed in Group 2 and 3 during the recovery period which lasted about 90 minutes, almost the same as the duration of drugs for spinal anesthesia, No complications were noticed in the 3 group during the periods of one week one month and two months. All specimens were examined and no abnormal findings were observed in the 3 groups. All specimens of the 3 groups were investigated under electrom microscopic examination and they revealed mild vacuolizations scattered in axon and ummyelinated nerves on the only some of the specimens and these were not significant. Severe nerve damage which was seen in the meperidine group of a preliminary experiment was not observed in this study. As a result of this investigation, we have not observed significant toxic effects microscopically or fuctioually.