BACKGROUND: Utilizing tissue engineering technique, various gel systems are served as scaffolds to repair bone defect. The scaffolds should have features of nontoxic and no teratological effects to the body. OBJECTIVE: To observe the effect of sodium alginate-gelatin/osteoblast gel on chromosomal pattern aberration in rabbits. DESIGN, TIME AND SETTING: The in vivo material animal experiments were conducted at the Beijing Shijitan Hospital and Department of Histology and Embryology, Peking University Health Science Center from October 2007 to March 2008. MATERIALS: A total of 12 New Zealand rabbits, aged 2 months, with clean grade, were randomly divided into 2 groups. The experimental group contains 4 female and 4 male rabbits, and the remaining 4 females were served as the control group. Sodium alginate dried powder were purchased from Sigma, USA, and the gelatin dried powder were supplied by Liidao Company, Hebei, China. METHODS: Following numbering, bone marrow was collected from 12 rabbits. Bone marrow stromal stem cells (BMSCs) were isolated by the density gradient centrifugation, and then in vitro cultured with osteoblast inductor. Osteoblasts following passage were an order of magnitude of 10~7. Bright pink gelatiniform liquid with mass ratio of sodium alginate and gelatin at ratio of 2:3 was prepared. Rabbit osteoblasts with final concentration of 5×10~9/L were mixed with CaCb solution to form fruit jelly-shaped sodium alginate-gelatin/osteoblast gel. Critical-sized calvarial defects were created in diameter of 1.5 cm in 12 rabbits. After 1 week, cell/scaffold complex (0.5 mL) was implanted to repair the bone defect in the experimental group. There was no treatment in the control group. MAIN OUTCOME MEASURES: The change of chromosomal pattern was observed at 3 months following reparation. RESULTS: No Chromosome somatotype aberration was found in 100 metaphases in the experimental group. From 400 metaphases of the control group, 4 abnormal cells were found, with 1% chromatid-type aberration ratio. Meantime, 12 abnormal cells in 800 metaphases of the control group were found, with 1.5% chromatid-type aberration ratio. The numerical value was within the normal range. Chromosome karyotype analysis: the chromosome number of each experimental rabbit was 2n=44, karyotype of the control rabbit was 44, XX, which was normal female; or 44, XY, normal male, no abnormal was found. The female rabbit in the experiment group was 44, XX, no abnormal was seen. CONCLUSION: From the cytogenetoxicity point of view, sodium alginate-gelatin/osteoblast gel is safe in repairing bone defects.

BACKGROUND:Rehabilitation training equipments play an important role in the rehabilitation treatment. Because of poor muscle strength and joint mobility in patients, we must guarantee the safety of rehabilitation training equipments.
OBJECTIVE:To design a new suitable man-machine interface that ensures patients can use rehabilitation equipments and even parts of fitness equipments safely.
METHODS:Through user experience research, we found the flaws of the existing rehabilitation equipment. Depending on the principles of ergonomics, we designed a new man-machine interface for upper limb exercise through survey and computer-aided design.
RESULTS AND CONCLUSION:The new man-machine interface program achieves the rapid wear and discharge between patients and rehabilitation training equipment, and importantly, it can automatical y separate people from the equipment when the patient's body discomforts or equipment failure appears. What’s more, this man-machine interface can be promoted to other fitness equipments. As a result, rehabilitation training for patients wil be more convenient.

Objective In order to get reference data for diagnosis of clinical genetic disease through analyzing chromosome ab‐normality types and rates in 885 patients who ask for cytogenetics consultation in recent years .Methods 324 newborns who asked for cytogenetics consultation because of high risk factors in down′s screening during pregnancy or found abnormality in physical ex‐amination after birth and 561 patients with history of spontaneous abortion ,infertility or fetal death ,growth or mental retardation , sexual abnormality were examined for karyotype analysis .Results 116 cases of chromosome abnormal karyotypes were detected , count for 13 .11% ,among which ,40 cases(34 .48% ) are chromosomal aberration .Chromosome abnormality types and rates are dif‐ferent in patients with different type of diseases .Conclusion Abnormalities in chromosome numbers and sex chromosome abnor‐mality account for the main causes of growth and mental retardation ,abnormalities of sexual differentiation and development ;but for couples suffered from spontaneous abortion ,polymorphism and structure abnormalities takes up the highest portion .

OBJECTIVETo diagnose a neonate presenting with multiple dysmorphic features, Cri-du-chat signs and hypoglycemia and to correlate the phenotype with the genotype.

METHODSThe patient was diagnosed with conventional cytogenetics and real-time fluorescence quantitative PCR (QF-PCR). The phenotype was then correlated with the genotype through a review of literature.

RESULTSThe neonate was diagnosed with a partial 13q trisomy (q12 → qter) and partial 5p monosomy (p15 →pter).

CONCLUSIONA rare diagnosis has been established with combined cytogenetic and molecular genetic techniques. QF-PCR has a broad application in genetic diagnosis.

Chromosomes, Human, Pair 13 ; genetics ; Chromosomes, Human, Pair 5 ; genetics ; Cri-du-Chat Syndrome ; diagnosis ; genetics ; Cytogenetics ; Female ; Humans ; Infant, Newborn ; Infant, Newborn, Diseases ; diagnosis ; genetics ; Male ; Trisomy ; diagnosis ; genetics

Objective:To investigate the association between serum zinc levels and convulsive brain injury in infants with mild gastroenteritis complicated with benign infantile seizures (BICE) and febrile seizures (FC).Methods:A case-control study method was conducted. 120 children with mild gastroenteritis and convulsion admitted to the First Affiliated Hospital of Hebei North University from January 2020 to January 2022 were enrolled as the research subjects. They were divided into BICE group and FC group according to the type of convulsion. The serum zinc level, the frequency and duration of convulsion, and the occurrence of convulsive brain injury in the two groups were recorded. Multivariate Logistic regression analysis was used to screen the risk factors for convulsive brain injury. The Spearman correlation method was used to analyze the association between serum zinc levels, clinical characteristics of convulsion and convulsive brain injury.Results:A total of 120 children were enrolled, of which 81 developed to BICE and 39 developed to FC during hospitalization. The serum zinc level of children in the FC group was significantly lower than that in the BICE group (μmol/L: 39.24±6.50 vs. 48.65±7.21, P < 0.01). In the BICE group and FC group, the serum zinc level in children with more than 2 convulsions was significantly lower than that in the children with one convulsion (μmol/L: 37.65±6.50 vs. 53.17±7.55 in the BICE group, and 30.27±5.58 vs. 44.16±7.57 in the FC group, both P < 0.01). Serum zinc level in children with convulsion duration ≥5 minutes was significantly lower than that in the children with convulsion duration < 5 minutes (μmol/L: 38.75±6.74 vs. 51.21±7.58 in the BICE group, and 31.08±5.46 vs. 45.19±7.25 in the FC group, both P < 0.01). Moreover, the serum zinc level of children with different convulsion frequency and duration in the FC group was significantly lower than that in the BICE group (all P < 0.01). Among the 120 children, 9 cases of convulsive brain injury occurred, and the incidence rate was 7.50%. The incidence of convulsive brain injury in the BICE group was 1.23% (1/81), which was significantly lower than 20.51% in the FC group (8/39, P < 0.01). The serum zinc level of children with convulsive brain injury was significantly lower than that of children with non-brain injury (μmol/L: 28.50±5.00 vs. 60.22±7.31, P < 0.01), and the number of convulsion was significantly higher than that of non-cerebral injury (≥ 2 convulsions: 100.00% vs. 1.80%, P < 0.01), and the duration of convulsion in children with brain injury was significantly longer than that of non-brain-injured children (convulsion duration ≥5 minutes: 100.00% vs. 11.71%, P < 0.01). Multivariate Logistic regression analysis showed that decreased serum zinc level [odds ratio ( OR) = 2.147, 95% confidence interval (95% CI) was 1.354-3.403], increased number of convulsion ( OR = 3.452, 95% CI was 1.266-9.417), and prolonged convulsion duration ( OR = 3.117, 95% CI was 1.326-7.327) were independent risk factor for convulsive brain injury in children with mild gastroenteritis and convulsion (all P < 0.05). Spearman correlation analysis showed that serum zinc level, convulsion ≥2 times, duration of convulsion ≥5 minutes and convulsion ≥2 times + convulsion duration ≥5 minutes were significantly negatively correlated with the occurrence of convulsive brain injury in FC children ( r values were -0.546, -0.517, -0.522, and -0.528, all P < 0.01). There was no significant correlation between serum zinc level, convulsion ≥2 times, convulsion duration ≥5 minutes and convulsion ≥2 times+convulsion duration ≥5 minutes and convulsive brain injury in BICE children ( r values were -0.281, -0.129, -0.201, -0.243, all P > 0.05). Conclusions:Serum zinc level is related to the characteristics of convulsive symptoms in children with mild gastroenteritis complicated with FC, and has a strong negative correlation with the occurrence of convulsive brain injury. Active targeted intervention and treatment may help reduce the incidence of brain injury in children.