Objective To explore the influences of different altitude environments on the performance of the portable dental unit.Methods Three regions with increasing altitudes(A(70.0 m),B(3 857.0 m)and C(4 820.0 m))were selected,and relevant environment parameters in the regions were measured including average room temperature,average atmospheric pressure and average air density.The performance indicators of the portable dental unit were tested in the three regions such as preparation time(Tprep),continuous working time(Tcont),working heat generation and handpiece output pressure,and the test results of region A were compared with those of region B and C.SPSS 29.0 statistical software was used for data analysis.Results The average atmospheric pressure and average air density were significantly lower in region B and C than in region A,and the differences were statistically significant(P＜0.05).The portable dental unit had the average Tprep prolonged andTcont shortened significantly in region B and C when compared those in region A(P＜0.05),whose mean working heat generation after 15-min operation was higher and mean handpiece output pressure was lower obviously in region B and C than in region A(P＜0.05).Conclusion High er altitude environments can have negative effects on the performance of the portable dental unit when compared with lower altitude environments.[Chinese Medical Equipment Journal,2024,45(5):52-55]

Objective To investigate the clinical effect of orthopedic robot combined with Starr pelvic reduction frame in the treatment of Tile type C pelvic ring fracture.Methods From October 2019 to May 2021,14 patients with type C pelvic ring fracture were treated with robotic combined with Starr pelvic reduction frame,including 9 males and 5 females.The age ranged from 33 to 69 years.All the 14 patients had fresh closed fractures without femur,tibia and fibula fracture.Surgery was complet-ed from 4 to 7 d after hospital admission.During the operation,the X-ray carbon bed was used,the pelvic ring was reduced by Starr pelvis reduction frame,and pelvic ring fracture was treated by orthopedic robot.Operation time,bleeding volume,fluo-roscopy times of single screw placement,fracture reduction quality,affected limb function and complications were observed.Radiological reduction was evaluated using Matta scoring standard,and clinical efficacy was evaluated by Majeed pelvic func-tion scoring system at the final follow-up.Results All of 14 patients successfully completed the operation,the operation time was 84 to 141 min,the bleeding volume was 20 to 50 ml,and the fluoroscopy times of single screw insertion was 4 to 9 times.All of 14 patients were followed up for 12 to 24 months.The healing time was 3 to 7 months.No complications such as fracture of internal fixation,screw loosening,infection and nerve injury were found.According to the evaluation criteria of Matta imag-ing reduction,9 cases were excellent,4 cases were good,and 1 case was fair.At the final follow-up,Majeed pelvic function scoring system was used:10 cases were excellent,4 cases were good.Conclusion The treatment of type C pelvic ring fracture with robotic combined Starr pelvis reduction frame is simple,time-saving,less trauma,less complications and effective.

Objective:To analyze the genotypes distribution of common and rare thalassemia in people of reproductive age in Huadu district of Guangzhou,enhance the database of thalassemia.Methods:Peripheral blood samples were collected for genotype analysis in Maternity and Child Health Hospital of Huadu District from January 2016 to October 2022.Gap-PCR and Reverse dot blot hybridization were used to detect common thalassemia genotypes.DNA sequencing was performed in samples suspected of rare genotypes.Results:A total of 16 171 subjects were identified as thalassemia carriers,and the positive rate was 44.41％(16 171/36 412).The genotypes of 114 cases(0.31％)were rare.A total of 10 845 cases were identified as α-thalassemia carriers(29.78％),and--SEA/αα was the most common genotype in those people,followed by-α3.7/αα and-α4.2/αα.A total of 4 531 subjects were identified as common β-thalassemia carriers(12.44％).The most common β-thalassemia mutation in the population was β41-42/βN,followed by β654/βN and β-28/β N.A total of 681 subjects were identified as αβ thalassemia carriers(1.87％),among them--SEA/αα compounded withβ CD41-42/β N was the most common genotype.A total of 48 cases were identified as rare α-thalassemia carriers,14 types of mutations,in which Fusion gene/αα was the most common.A total of 52 cases were identified as rare β-thalassemia carriers,11 types of mutation,in which βSEA-HPFH/βN was the most common.Conclusion:The thalassemia genotypes in Huadu district are complex and diverse.We should attach great importance to the detection of rare thalassemia genotypes.

Objective: To investigate the distribution of blood pressure and analyze the associated factors of blood pressure of the elderly with type 2 diabetes in Jiangsu Province. Methods: The elderly over 60 years old participants with type 2 diabetes in the communities of Huai'an City and Changshu City, Jiangsu Province were selected in this study. They were divided into two groups: taking antihypertensive drugs and not taking antihypertensive drugs. The demographic characteristics, such as age and sex, and relevant factors were collected by questionnaire. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured by physical examination. The percentile of SBP and DBP in each age group of men and women were described. The kernel density estimation curve was used to show the blood pressure distribution. The trend of blood pressure with age was fitted by locally weighted regression. The logistic regression model was used to analyze relevant factors of blood pressure. Results: A total of 12 949 participants were included in this study, including 7 775 patients in the antihypertensive drug group and 5 174 patients in the group without antihypertensive drugs. The SBP of participants was concentrated at 140-160 mmHg, and their DBP was concentrated at 75-85 mmHg. There were significant differences in the distribution of blood pressure among the subgroups of body mass index (BMI) and rural areas whether taking antihypertensive drugs and not. For participants aged under 80 years old, the SBP showed an increasing trend with age and the DBP showed a decreasing trend with age. Age, BMI ≥24 kg/m², fasting blood glucose ≥7.0 mmol/L, living in rural areas and no smoking were influencing factors of the elevated SBP; BMI ≥24 kg/m², male, living in rural areas, no smoking, drinking alcohol and not receiving drug hypoglycemic treatment were influencing factors of the elevated DBP. Conclusion: The SBP of older diabetic adults in Jiangsu Province is at a high level, and the distribution of blood pressure is significantly different between men and women in taking antihypertensive drugs group. The SBP presents a rising trend and the DBP is decreasing at the age of 60-80 years. The blood pressure level of this population are mainly affected by age, BMI, urban and rural areas, smoking.
Adult ; Aged ; Humans ; Male ; Female ; Middle Aged ; Aged, 80 and over ; Blood Pressure/physiology* ; Diabetes Mellitus, Type 2/epidemiology* ; Antihypertensive Agents/therapeutic use* ; Smoking ; Body Mass Index ; Hypertension/epidemiology*

OBJECTIVE: To explore clinical efficacy of staged surgery in treating complex closed Pilon fracture. METHODS: From June 2019 to January 2021, 29 patients with complex closed Pilon fracture were treated by staging surgery, including 18 males and 11 females, aged ranged from 31 to 68 years old with an average of (43.50±6.62) years old;7 cases were typeⅡand 22 cases were type Ⅲ according to Ruedi-Allgower classification. All patients had fresh closed fractures without talus and calcaneal fractures. The time from injury to closed reduction and external fixation, the interval between two stages of surgery, fracture healing time and complications were recorded. American Orthopedic Foot and Ankle Society(AOFAS) was used to assess clinical effects. Burwell-Charnley system was used to evaluate radiological reduction. RESULTS: All 29 patients were followed up from 13 to 30 months with an aver age of (15.43±5.31) months. All fractures healed well from 2 to 6 months with an average of (3.77±1.22) months. No internal fixation fracture, screw loosening, infection, internal fixation irritation, ankle stiffness occurred. The time from injury to closed reduction and cross-ankle fixation ranged from 1.22 to 7.34 h with an average of(2.31±3.52) h, the interval between two stages ranged from 5 to 9 days with an average of (5.98±2.11) days. AOFAS score was improved from 34.11±6.89 before operation to 90.10±10.11 after oepration at 12 months(P<0.05). According to AOFAS grading, 16 patients got excellent result, 9 good and 4 moderate. Fifteen patients got anatomic reduction, 12 patients were good reduction, and 2 cases were poor reduction according to Burwell-Charnley system. CONCLUSION Staged surgery for complex closed Pilon fracture has advantages of less complications, statisfied reduction, stable fixation, which could obtain good recovery of ankle joint.
Adult ; Aged ; Ankle Fractures/surgery* ; Ankle Injuries/surgery* ; Female ; Fracture Fixation, Internal ; Fracture Healing ; Humans ; Infant ; Male ; Middle Aged ; Tibial Fractures/surgery*

OBJECTIVE: To retrospectively analyze the clinical and CT imaging features of desmoplastic ameloblastomas (DA) in comparison with other types of ameloblastomas. METHODS: Patients diagnosed with ameloblastoma histopathologically in Peking University School and Hospital of Stomatology from July 2000 to August 2017 were reviewed to analyze the constituent ratios and characteristics of DA. CT imaging features of DA (28 cases) were investigated in comparison with consecutive cases of solid/multicystic and unicystic ameloblastomas. The following imaging perspectives were analyzed: the border, internal structure, three-dimensional shape, tooth, the periodontium, the cortex and the expansion of the tumors. CT values were measured in the region of interest for quantitative analysis. RESULTS: Among the 1 269 cases of ameloblastomas, 50 (3.9%) were DA, which showed predilections for males (74.0%). The average age of DA was about 43.9 years old, which was higher than the other two types. The anterior incisorcanine region (62.0%) and premolar region (30.0%) were most frequently affected. The incidence rate of DA in mandibule was 56.0% (28/50), which was slightly higher than that of maxilla (44.0%). The DA characteristically showed scallop border and honeycomblike or soapbubble internal structure with bone formation on CT. The mean ratios of height to mesiodistal and buccal-lingual to mesio-distal distances were 0.76 and 0.63, which were higher than the other two types. According to the degree of internal bone formation, three subtypes of DA could be observed: densely ossifying type (I), honeycomb/soap bubble type (II) and sparsely ossifying type (III). The means and standard deviations of CT values of DA were significantly higher than those of the other two types, which were (488.8±164.0) HU (type I), (171.7±102.8) HU (type II), (42.1±8.8) HU (type III). CONCLUSION CT is helpful for diagnosis of DA, which shows as solid tumor with varying degrees of internal ossification.
Adult ; Ameloblastoma ; Female ; Humans ; Jaw Neoplasms ; Male ; Maxilla ; Retrospective Studies ; Tomography, X-Ray Computed

OBJECTIVE: To evaluate the association between rotator cuff tear and the proximal migration of humeral head. METHODS: In this research, we retrospectively selected 30 patients with unilateral rotator cuff tear in Peking University People's Hospital from September 2015 to May 2016, who received magnetic resonance imaging (MRI) and X-ray of the painful shoulder before enrollment in this study, the duration between the two examinations was no longer than 1 week, and also there was no past history of surgery in the selected shoulders. There was no other exclusion criteria. Upward migration index (UMI) was the ratio between the distance of humeral head center to the lower surface of acromion, and the radius of humeral head circle, which could help to minimize the effect of anatomy difference and imaging magnification, compared with the traditional acromiohumeral distance (AHD). Then we introduced this index to stratify the selected 30 patients into 3 groups, and each group contained 10 patients, UMI of group 1 was >1 and ≤1.2, UMI of group 2 was >1.2 and ≤1.4, UMI of group 3 was >1.4. As the supraspinatus was most commonly affected by pathological change among the four rotator cuff tendons, we took it as the research object. Then we used the Spearman correlation analysis to evaluate the relationship between UMI and fatty degeneration, rotator cuff tear size and the thickness of ruptured supraspinatus tendon from X-ray and MRI. RESULTS: In the A-P view, the average UMI was 1.33 (1.02-1.51, SD: ±0.22). UMI and the tear size had a significant negative correlation (R=-0.584, P<0.01), and also there was a negative correlation between the fatty degeneration of the supraspinatus (R=-0.312, P=0.033). However, there was no correlation between UMI and the thickness of ruptured supraspinatus (R=0.127, P=0.071). CONCLUSION UMI is related with the fatty degeneration of supraspinatus and the tear size. The reduction of UMI is a predictable and reliable mark of rotator cuff tear and degeneration in clinic. Physicians can use physical examination and X-ray first when facing the patients with shoulder pain, which is convenient and helpful for evaluating rotator cuff tears.
Humans ; Humeral Head ; Magnetic Resonance Imaging ; Retrospective Studies ; Rotator Cuff ; Rotator Cuff Injuries ; Shoulder Joint

BACKGROUND: The application of mesenchymal stem cells (MSCs) in the treatment of cartilage damage has become a hot spot of research. Further studies on the distribution of MSCs in the body after injection and on the underlying mechanism of action are needed. OBJECTIVE: To observe the migration of bone marrow mesenchymal stem cells (BMSCs) after injection into the region of osteochondral defect. METHODS: Thirty Sprague-Dawley rats were randomized into two groups (n=15 per group). In the control group, the femoral tochlear was exposed but an osteochondral defect was not made; and after the suture, PKH26-labeled BMSCs were directly injected into the articular cavity of rats. In the experimental group, a cartilage defect of 1 mm in diameter and 1 mm in depth was made in the rat femoral trochlea, and 5×106PKH26-labeled BMSCs were injected into the defect after operation. At 1, 3 and 7 days after injection, the femoral condyle was taken to make frozen sections followed by DAPI staining. The distribution of BMSCs was observed under laser scanning confocal microscope. RESULTS AND CONCLUSION: In the control group, PKH26-labeled BMSCs were not transferred to the subchondral bone. In the experimental group, BMSCs were detected in the subchondral bone area at 1, 3 days after injection of PKH26-BMSCs in the bone cartilage defect area, and the BMSCs were also found in the bone marrow cavity at 7 days after injection. In conclusion, BMSCs in the articular cavity cannot migrate into the subchondral bone and bone marrow cavity unless the cartilage of the femoral condyle is damaged.

OBJECTIVETo explore the expression of PXR (Pregnane X receptor) in several malignant hematological cell lines, and to investigate the reversal effect of Gambogic acid (GA) on multi-drug resistance (MDR) of K562/A02 cell line and its reversal mechanism.

METHODSTranscription of PXR was detected by real-time PCR in several malignant hematological cell lines. The growth inhibition rate of K562/A02 in different experimental groups was assayed by MTT method, and the expression of PXR protein was measured by Western blot.

RESULTSPXR gene transcription could be detected in several hematological malignancy cell lines, and it was significantly higher in K562/A02 cell line, compared with the other cell lines used in this experiment. Low-dose GA could enhance cell growth inhibition rate, increasing the effect of chemotherapy, which may be associated with down-regulation of PXR expression. PXR gene transcription and protein expression in GA and DNR+GA groups decreased as compared with control group and the DNR group, suggesting that low-dose GA can down-regulate PXR gene transcription and protein expression.

CONCLUSIONPXR gene transcription can be detected in several hematological malignancy cell line, which is significantly higher in K562/A02 cell line, as compared with the other cell lines used in this experiment. Low-dose GA can enhance cell growth inhibition rate, increasing the effect of chemotherapy, which may be associated with down-regulation of PXR expression.

Citrates ; Daunorubicin ; Down-Regulation ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Humans ; K562 Cells ; Leukemia ; Real-Time Polymerase Chain Reaction ; Receptors, Steroid ; Xanthones

OBJECTIVETo analyze the results of clinical and bacteriological examinations in patients with crush syndrome who suffered infectious complications after an earthquake in Sichuan, China.

METHODSA total of 313 bacteriological samples among 147 patients with crush syndrome were collected. Infectious complications, results of microbiological examinations, potential risk factors of infection and mortality were analyzed statistically.

RESULTSIn the obtained database, 112 out of the 147 (75.7%) patients had infectious complications, in which, wound infection, pulmonary infection, and sepsis were most common. The time under the rubble and the time from injury to treatment were related to the occurrence of wound infection (P equal to 0.013, odds ratio 2.25; P equal to 0.017, odds ratio 2.31). Sepsis and wound infection were more common in patients who underwent fasciotomy or amputation than in those who did not (P equal to 0.001).

CONCLUSIONQuick rescue and injury treatment can decrease the infection risk in crush syndrome patients. It is better to obtain microorganic proofs before applying antibiotics, and bacteriological and drug sensitivity data should be taken into account, especially considering that most of these infections are hospital-acquired and drug resistance. Emphasizing the accuracy and efficiency of wound management in emergency situations, cautiously assessing the indications for fasciotomy to avoid open wounds from unnecessary osteofascial compartment decompression incisions may decrease the incidence of infection and ameliorate the prognosis.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Bacterial Infections ; etiology ; Child ; Child, Preschool ; China ; Crush Syndrome ; complications ; microbiology ; Earthquakes ; Female ; Humans ; Male ; Middle Aged ; Risk Factors