BACKGROUND:Calcium citrate has a better solubility than calcium phosphate, calcium sulfate, and other calcium biomaterials. The synthetic calcium citrate has a good denseness, and stably releases calcium ions at a high efficiency during the degradation. Consequently, it may be more suitable for the fil ing of fracture defects, providing needed calcium ions for early fracture healing.
OBJECTIVE:To prepare calcium citrate biomaterials with a novel formulation based on the natural bio-mineralized oyster shel s and citric acid so as to expect to get a good application in fracture healing repair.
METHODS:Crushing, grinding, and chemical reaction methods were used for refinement. Particle size analyzer, X-ray diffraction, scanning electron microscope, and Fourier transform infrared spectroscopy were adopted for analysis of the size distribution, composition, mineral phases, and micro-morphology. Biological characteristics were evaluated through a simulated body fluid experiment.
RESULTS AND CONCLUSION:Oyster shel powder was reacted with saturated citric acid to produce the calcium citrate material that had uniform crystal structure and compact bonding among crystal bodies, and exhibited a certain mechanical ability. The calcium citrate material had a good crystal structure that was conductive to prolong the degradation time. The calcium citrate released calcium ions slowly, and did not produce dramatic changes in the pH value (7.20-7.46) of the surrounding in the dissolution process. With the gradual degradation of calcium citrate materials, Ca2+concentration in solution increased gradual y and stably, and ultimately achieved an appropriate concentration of 7 mmol/L, suitable for osteoblast proliferation and differentiation. Calcium citrate prepared using natural oyster shel has good biological properties, and exhibits a natural superiority to artificial bone materials.

Objective To explore the clinical feature, gene mutations and treatment of isolated hypogonadotropic hypogonadism (IHH). Methods The clinical data from a case of IHH and his families were retrospectively analyzed. The related literatures were reviewed. Results The propositus was a 7-year-old boy with a small penis and testes, whose younger brother was 5-year-old with a small penis and cryptorchidism. In both boys testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH) levels were low. The GnRH provocation test was not reactive. Their parents denied the consanguineous marriage. Illumina sequencing revealed that both of the brothers had homozygous mutation of GnRHR gene in C.806C>T, and their parents were heterozygous mutations in C.806C>T gene. After confirmation of the diagnosis, human choronic gonadotropin (hCG) treatment was given. The levels of testosterone and dihydrotestosterone were significantly increased after 6 weeks. Conclusion The combination of clinical phenotype, biochemical analysis, and gene detection is helpful for early diagnosis of IHH.

Objective To investigate the characteristics and essential points of diagnosis and treatment of double trisomy 47,XXX/48,XXX,+8 combined Behcet disease, a rare inherited immunodeficiency disorder. Methods The clinical manifestations, karyotype analysis and gene test results of the patients were analyzed, and relevant literatures were reviewed. Results A 11-year-old girl presented repeated fever for more than 6 years, accompanied with recurrent genital herpes infection and oral apthosis, was clinically diagnosed with Behcet disease. Cytogentic and molecular karyotyping on peripheral lymphocytes demonstrated 47,XXX[12]/48,XXX,+8[18]. Conclusions Conventional karyotype analysis and chromosomal microarray analysis have a complementary role in the diagnosis of the disease. We conclude that patients with constitutional trisomy 8 and those with trisomy 8 confined to the bone marrow are both at increased risk of developing features of Behcet disease. The mechanism may relate to increased gene dosage of candidate genes for Behcet's disease on chromosome 8.

Humans ; Severe Acute Respiratory Syndrome ; diagnosis ; therapy