BACKGROUND:Correlation between subchondral bone and articular cartilage in the process of osteoarthritis has not been fuly elucidated. Degeneration of cartilage is the focus of attention, and the subchondral bone also plays an important role in the process of osteoarthritis. OBJECTIVE: To observe the differences between experimental osteoarthritis models in rabbit knees established by two kinds of surgical methods and two kinds of proteases inducing methods, and to explore the correlation between subchondral bone mass and degeneration of cartilage. METHODS:Thirty-two New Zealand rabbits were randomly and averagely divided into four groups: Hulth group (group A), anterior cruciate ligament transaction group (group B), colagenase type II group (group C) and papain group (group D). The right knees of rabbits were established as osteoarthritis models, and the left knees served as controls. Bone mineral density of the knee joint was evaluated by dual-energy X-ray absorptiometry scanning at 0, 4 and 8 weeks after modeling. The rabbits were sacrificed at 8 weeks after MRI scanning, bilateral knee joints were harvested for general and histological observation. Quantitative analysis was done according to Mankin scores. RESULTS AND CONCLUSION: Bone mineral density of the right knees decreased at 0, 4 and 8 weeks after modeling, and the rank was as folows: group A > group B > group C > group D. MRI scanning showed that the articular cartilage thickness of the medial and lateral femoral condyle on the right knees became thinner compared with the left side, and the rank was as folows: group A < group B < group C < group D. Observation by specimens and pathological slices showed that the articular cartilage degeneration of the surgery groups worsened, group A was the most serious one, and group 1D was the lightest. Both surgery and proteases inducing methods can successfuly establish osteoarthritis models in rabbit knees. Surgery inducing models resemble the advanced or intermediate stage of osteoarthritis, while the proteases inducing models resemble the early stage of osteoarthritis. Degeneration of the articular cartilage and changes of subchondral bone are related in progressive development.

BACKGROUNDDuring the process of bone cement joint replacement, some patients show a series of complications, such as a sudden drop in blood pressure or dyspnea. The cause of the complication is considered to be due to emboli caused by the femur prosthesis insertion. The purpose of the present study was to detect the pulmonary embolism in rabbits after bone cement perfusion by radioimmunoimaging, and to explore its protective measures.

METHODSForty rabbits, 2.5 - 3.0 kg weight, were randomly assigned to four groups, with ten rabbits in each group. Group I (no intervention): Bone cement perfusion was done after medullary cavity reaming and pressurizing. Group II (epinephrine hydrochloride intervention): The medullary cavity was rinsed with a 1:10 000 normal saline-diluted epinephrine hydrochloride solution followed by bone cement perfusion after medullary cavity reaming and pressurizing. Group III (fibrin sealant intervention): The medullary cavity was precoated with fibrin sealant followed by bone cement perfusion after medullary cavity reaming and pressurizing. Group IV (blank control group): The medullary cavity was not perfused with bone cement after reaming. In each group, the rabbits underwent femoral head resection and medullary cavity reaming. Before bone cement perfusion, 2 ml of developing tracer was injected through the ear vein. Radionuclide imaging was performed at 60, 120, and 180 minutes after bone cement perfusion, and the pulmonary radioactivity in vivo was measured. The rabbits were immediately sacrificed, and the pulmonary tissue was removed and its radioactivity was measured in vitro. Pulmonary tissue was then fixed and the pulmonary embolism and the associated pathological changes were observed.

RESULTSThe pulmonary radioactivity in vivo was measured at 60, 120, and 180 minutes after bone cement perfusion. The radioactivities of the four groups were 11.67 ± 2.16, 14.59 ± 2.92 and 18.43 ± 4.83 in group I; 8.37 ± 3.05, 10.35 ± 2.24 and 11.48 ± 2.96 in group II; 3.91 ± 1.19, 5.53 ± 2.95 and 7.25 ± 1.26 in group III; 1.04 ± 0.35, 1.14 ± 0.87 and 1.43 ± 0.97 in group IV. The radioactivities of groups I, II, III at 60, 120 and 180 minutes were significantly higher than group IV (P < 0.05). The pulmonary embolism could be detected. Pretreatment with epinephrine hydrochloride and fibrin sealant significantly decreased the pulmonary radioactivity in group II and group III, but it was still higher than in the group IV.

CONCLUSIONSRadioimmunoimaging is an alternative method for the dynamic observation of rabbit pulmonary embolism after bone cement perfusion. Radioimmunoimaging is the optional way to evaluate the effect of pretreatment with epinephrine hydrochloride or fibrin sealant on pulmonary embolism after bone cement perfusion.

Animals ; Bone Cements ; Pulmonary Embolism ; diagnosis ; Rabbits ; Radioimmunodetection ; methods

OBJECTIVETo analyze epidemiological characteristics of burn inpatients in Hainan province over 8 years.

METHODSSix thousand and ninety-nine burn patients admitted to 6 hospitals of Hainan province from January 2002 to December 2009 were enrolled in the study. The clinical data of these patients were analyzed retrospectively, including age, gender, injury cause, wound position, burn area, ailment prior to admission, admission time, medical insurance, length of hospital stay, and mortality rate, relationship among inpatient distribution, admission time, and ambient temperature at the time of admission. Data were processed with SPSS 13.0 software.

RESULTSThere were more burn male patients than female, with ratio of 2.1: 1.0. Most patients were younger than 13 years (57.2%, 3488/6099). The most common burn area was smaller than or equal to 10% TBSA (67.4%, 4108/6099), and the fewest patients had burn areas of over 50% TBSA (2.0%, 121/6099). The main causative agents were hot liquid and flame, accounting for 71.5% (4358/6099), 17.9% (1092/6099), respectively. Most patients had injuries of more than two body areas (60.7%, 3705/6099), and lower extremity injury (17.1%, 1042/6099) was predominant in wound of single body area. Among 703 cases who had other ailments prior to admission (11.5%), the highest rate of prior ailments was found in patients older than 60 years (18.5%, 48/260), it was lowest in children younger than 1 year (8.0%, 32/398). The length of hospital stay was 1 to 375 day, and the admission time was 10 minutes to 90 days after burn. Total mortality rate was 0.4% (26 cases). The number of inpatients aged from 19 to 59 was obviously higher in months with high ambient temperature (from June to August), and for inpatients younger than 13 years the incidence of burn injury showed no obvious seasonal change. The inpatients who had medical insurance accounted for 10.9% (66/603) to 19.5% (121/619) from 2002 to 2005, which increased to 46.0% (372/808) in 2007 and 79.1% (869/1098) in 2009.

CONCLUSIONSFor burn inpatients in Hainan province, the main injury cause of burn injury is hot liquid, the number of burn adults aged from 19 to 59 seems to increase in months with high ambient temperature, while the incidence of burn in children showed no obvious seasonal change. The number of inpatients and those with medical insurance showed a tendency of increase from 2005 to 2009 in Hainan province.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Burns ; epidemiology ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Incidence ; Infant ; Inpatients ; Male ; Middle Aged ; Retrospective Studies ; Young Adult

Alcoholism ; metabolism ; pathology ; Animals ; Humans ; Orexins ; metabolism