Chronic Disease ; Graft vs Host Disease ; therapy ; Hematopoietic Stem Cell Transplantation ; Humans

Objective:To assess mechanical hyperalgesia of the bilateral masseter muscles following the induction of experimental unilateral malocclusion in rats. Methods:① An elastic rubber(3M Unitek,1/8#) was inserted between the first and sencond upper molars on the left side of 4 Sprague- Dawley rats to induce malocclusion.② The left maxillary first molar of 4 rats were filled with metal arsenic for 7 days to inactivate tooth pulp, and then a dentin pin(d 0.75 mm, long 1.5-2.0 mm,0.5-1.0 mm above the occlusion surface)was bonded in the pulp chamber to induce acute traumatic occlusion, and 4 control animals were treated as the same procedure but not raised occlusion surface.③ According to Ren's method, von Frey filaments were used to assess the muscle mechanical threshold.Head withdrawal, leg raising and crying were observed as painful actions. Results:① In gradually induced malocclusion group,hyperalgesia was induced in bilateral masseter muscles from 3 to 9 d, and the peak time was the 7th day. ②In the acute traumatic occlusion group, the ipsilateral masseter muscle was demonstrated hyperalgesia for 5-7 days, and the peak time was the 2nd day. Conclusions:Traumatic occlusion may lead to masseter muscles hyperalgesia, and there existe some differences for pain behavior between the acute and the chronic occlusion trauma.

BACKGROUND:In allogene hematopoietic stem cell transplantation,the choice of preconditioning scheme is an important link of the success of hematopoietic stem cell transplantation,and a major research direction of stem cell transplantation.The myeloablative pretreatment scheme has great toxicity,and pretreatment related death rate is high.Thus,it is necessary to explore an ideal pretreatment scheme to expect a decrease in side effects and relapse.OBJECTIVE:To observe the effect of modified Bu/CY pretreatment regimen for treating hematologic malignancies.METHODS:The 8 patients were selected at the Department of Hematology,Haikou Municipal People's Hospital Affiliated to Xiangya School of Medicine,Central South University from November 2003 to March 2008,and received modified Bu/CY pretreatment:cytarabine 2.0-3.0 g/(m2·d)×2 d,intravenous drip,for 24 consecutive hours;myleran 4 mg/(kg·d)×3 d;cyclophosphamide 50 mg/(kg·d)×2 d;methyl-cyclohexyl nitrosourea 25 mg/(m2·d)×1 d;antithymocyte globulin 25 mg/(kg·d)×4 d. We have increased the arabinosylcytosin dose twice,and changed to a 24-hour infusion via intravenous drip,so that pretreatment strength was increased and promote lasting implantation of hematopoietic stem cells,based on the modified program.Graft-versus-host disease(GVHD)prevention:cyclosporin A and mycophenolate mofetil would be used advanced to minus 7 days (one day before stem cell transfusion is minus 1)based on the classic methotrexate regimen.The ABO blood group changes and DNA were tested in patients before and after ransplantation.RESULTS AND CONCLUSION:①The detection of hematopoietic reconstitution after transplantation:All patients have received hematopoietic reconstitution,with no pretreatment-related death.The white blood cells reduced to 0 after-3- +7 days of hematopoietic stem cell transplantation,and continues to(3-22)days,+10- +21 days white blood cells ＞ 1.0×109/L,+11- +51 days,platelets ＞ 20x109/L.②Incidence of GVHD:of 8 patients,there were GVHD Ⅳ grade(intestinal)in 1 case,acute graft-versus-host disease grade Ⅰ-Ⅱ in 3 cases.Above-mentioned results indicated that the further modification of BU/CTX2 regimen may be an effective pretreatment program,with a few side effects,which is better than the classic total-body irradiation/CY regimen.What's more,it is simple accurate,reliable rote of anti-leukemia and will be a safe and effective method for treating hematologic malignancies.

BACKGROUND: Effective mobilization and collection of hemopoietic stem cells are initial factors for peripheral stem cell transplantation, while they make sure a permanent reconstruction of hemopoiesis. Mobilization and collection have been developed; however, the collection is more, and the yield of hemopoietic stem cells is various. OBJECTIVE: To investigate the best time of mobilization and collection of peripheral blood stem cells from healthy donors. METHODS: A total of 16 donors who were selected from Haikou People's Hospital between January 2003 and December 2008 were randomly divided mobilization group (A, n=6) and mobilization + collection group (B, n=10). A group was subcutaneously injected with 5.0-10.0 μg/(kg·d) recombinant human granulocyte colony-stimulating factor (rhG-CSF) (Filgrastim), and B group was treated with rhG-CSF and intravenously injected with 10 mg dexamethasone. Peripheral stem cells were collected twice in each group. The two groups were collected at the fourth and 5~(th) day of mobilization after the second or 4th hour subcutaneous injection of rhG-CSF. The collection was 4.0-5.0 mL, the manhandled volume was 3.0-5.0 mL, and the total blood volume was 6.7-10.1 L. RESULTS AND CONCLUSION: Number of mononuclear cells was (4.0-8.0)×10~8 kg~(-1) in the two groups. The cell concentration of fourth hour was higher than the second hour after rhG-CSF treatment (P < 0.05). The mononuclear cell concentration of fourth hour was higher than the second hour after the fourth and 5~(th) day of rhG-CSF treatment. Our research showed that we could collect sufficient amount of cells (to a high concentration) by one time, which had reasonable collection time - value-effectiveness relationship, when the cycle blood volume was 1.8-2.2 times of circulating blood volume.

OBJECTIVETo investigate the effect of gradually induced disordered occlusion (GIDO) on the expression of osteoprotegerin (OPG) and receptor activator of nuclear factor-kappaB ligand (RANKL) in mandibular condylar cartilage of rats.

METHODSTotally 48 rats, aged 8 weeks were included, and were divided into experimental and control groups randomly at 4 time points, with same gender distribution (n=3). By inserting elastic rubber band the right side mandibular first molar and the left side maxillary first molar were moved mesially. Four weeks later, the right side mandibular third molar and the left side maxillary third molar were moved distally with same method. In this way, the GIDO was established in rats. The rats were sacrificed at the end of 2th, 4th, 6th and 8th week respectively after the application of the GIDO. The expression of OPG and RANKL in condylar cartilage was examined with immunohistochemical method and calculated by the area of positive cell percentage.

RESULTSOPG and RANKL expressed predominantly in condylar cartilage hypertrophic layer. The rats in experimental group expressed a higher OPG level in all of the 4 time points than their age-matched controls (P<0.05), while RANKL were higher in 2, 6, 8 weeks subgroups (P<0.05), but not in 4 weeks subgroup. No differences were found between male and female subgroups.

CONCLUSIONThe present results suggest that both OPG and RANKL take part in the condylar cartilage remodeling procedure in the present rat model.

Animals ; Cartilage ; Female ; Humans ; Male ; Mandibular Condyle ; Molar ; Osteoprotegerin ; RANK Ligand ; Rats

OBJECTIVETo study the effects of experimentally created unilateral anterior crossbite prosthesis on the expression of parathyroid hormone-related peptide (PTHrP) and parathyroid hormone receptor-1 (PTH1R) in mandibular condylar cartilage of SD rat.

METHODSIn experimental groups, the unilateral anterior crossbite metal prosthesis was cemented to the left incisors of the maxilla and mandible of 6-week-old SD rats, respectively. Animals were sacrificed at 2, 4, 8 weeks. Hematoxylin-eosin (HE) staining were carried out for studying the morphological changes of the condylar cartilage. Immunohistochemical staining and real-time polymerase chain reaction (PCR) analysis were performed to detect the levels of expression of PTHrP and PTH1R in the condylar cartilages.

RESULTSThe obvious degenerative changes were found in the condylar cartilages in experimental group at 8 weeks. Comparing to the control group, the expression of PTHrP mRNA (P < 0.01) and protein(P < 0.01) in the experimental group were increased, whereas PTH1R mRNA (P < 0.01) and protein (P < 0.01) levels were decreased.

CONCLUSIONThe expression of PTHrP was increased in the condylar cartilage of rat with unilateral anterior crossbite metal prosthesis but its effects might be limited because of decreased expression of PTH1R in the condylar cartilage. The low level expression of PTH1R should be a part of the constitution of the molecular pathomechanism of temporomandibular joint osteoarthritis (TMJOA)-like lesion.

Animals ; Cartilage ; Cartilage, Articular ; Incisor ; Malocclusion ; Mandible ; Mandibular Condyle ; Osteoarthritis ; Parathyroid Hormone-Related Protein ; Prostheses and Implants ; Rats ; Rats, Sprague-Dawley ; Receptor, Parathyroid Hormone, Type 1 ; Temporomandibular Joint

Objective To evaluate the effect of doxepin on the expression of p38 mitogen-activated protein kinase (p38 MAPK) in the spinal cord of rats with neuropathic pain (NP).Methods Sixty clean-grade male Wistar rats in which intrathecal catheters were successfully implanted,weighing 200-250 g,were divided into 3 groups (n =20 each) by a random number table method:sham operation group (S group),NP group and doxepin group (D group).NP was induced by chronic constriction injury (CCI) to sciatic nerve.Doxepin 20 mmol/L (10 μl) was intrathecally injected at 3,7,14 and 21 days after CCI (T1-4) in group D.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before CCI (T0) and at T1-4.The rats were sacrificed after measurement of pain threshold at T4,and L4-6 segments of the spinal cord were removed for determination of the expression of p38MAPK protein by Western blot.Results Compared with S group,MWT was significantly decreased and TWL was shortened at T2-4,and the expression of p38MAPK protein was up-regulated in NP and D groups (P＜0.05).Compared with NP group,MWT was significantly increased and TWL was prolonged at T2-4,and the expression of p38MAPK protein was down-regulated in D group (P＜0.05).Conclusion The mechanism by which doxepin mitigates NP is related to down-regulating p38MAPK expression in the spinal cord of rats.

OBJECTIVETo compare the ultra-microscopic changes of periodontal Ruffini's corpuscle induced by different patterns of tooth movement, and investigate the influence of different changes of the periodontal mechanical environment on the periodontal mechanoreceptor.

METHODSThirty-two eight-weeks-old SD rats were divided into control group (n = 4), none-extraction group (n = 12) and extraction group (n = 12), and none-extraction group and extraction group were further divided into three subgroups, namely 3 day and 14 day and 28 day. For control group, no intervention was performed. For none-extraction group and extraction group, the following interventions were conducted. In none-extraction group, the maxillary left and mandibular right third molars were moved distally. In extraction group, the maxillary left third molar was moved distally, and the bilateral mandibular third molars were extracted. The ultra-structures of periodontal Ruffini's corpuscle in the periodontal ligament of the distal root of the bilateral maxillary third molars were observed under the transmission electron microscope.

RESULTSThe ultra-structrural changes in the none-extraction group were mainly characterized by degeneration or abnormal distribution of mitochondria in the axon terminal, which were almost recovered at 28 d. In the extraction group, the changes were mainly characterized by deficiency or abnormal elongation of the Schwann sheath and were not recovered at 28 d.

CONCLUSIONSThe ultra-structures of periodontal Ruffini's corpuscle might be influenced by tooth movement and occlusal changes, and the mechanorecepting function of it might be affected by changes of the periodontal mechanical environment.

Animals ; Mechanoreceptors ; physiology ; Molar ; Molar, Third ; Periodontal Ligament ; Rats ; Tooth Movement Techniques ; Tooth Root