Lowering of bone mineral density (BMD) includes metabolic and destructive reduction of BMD, the former usually relates to the changes of the whole body while the latter often affects the local parts. The lowering of BMD can be caused by so many reasons. This article analyzes the various situations and the possible causes of BMD reduction. It also points out the limitations of currently used method of measuring BMD and recommends the procedure of the diagnosis and differential diagnosis of primary osteoporosis.

Chemotherapy can induce bone loss. It is especially severe and the incidence of estimated bone loss may be as high as almost 100% for cancer patients treated with anti-sex hormone agents because of inhibition and deficiency of estrogens and/or androgens with the inappropriate ratio of two hormones during and "after therapy. Anti-sex hormone-dependent neoplasm agents-induced bone loss, characterized by an increase of bone turnover rate, should be treated in the early stage in order to prevent it from deterioration and bone fractures. The etiology, mechanism and clinical management of anti-sex hormone-dependent neoplasm agents-induced bone loss are briefly discussed in this review.

Metabolic balance (MB) tests of calcium (Ca) and phosphate (P) were performed on 51 diabetic patients and 28 controls which were divided into 5 groups: control, IDDM before and after treatment and NIDDM before and after treatment over 353 test days of MB altogether. Student's t and Hotelling's T2 analyses were used to test the differences among these groups on the variables of duration of diabetes, blood glucose, Ca and P levels, MB value and net intestinal absorption rate of Ca and P. The results showed that before treatment more negative MB values (Ca: - 346?136.9mg/d, P:-586?202.2mg/d) were found in IDDM than in NIDDM (Ca: -195 ?148.8mg/d, P: -372 ?2256.5mg/d). The MB value in IDDM became normal with inuslin therapy while it remained negative slightly in NIDDM despite of the fact that diabetes mellitus had been controlled, indicating that it was more difficult to correct the negative MB in NIDDM than in IDDM. As a significant negative correlation was found between blood glucose level and Ca MB (r=-0.80, P

Hotelling's T2 and stepwise regression analyses were used to study the results of metabolic balance test of magnesium (Mg) in 41 diabetic patients (IDDM 11, NIDDM 30). Negative metabolic balance of Mg was noted and serum Mg was lower in diabetics before treatment (2.1 +0.40 mg/dl, M+SD) than that of controls (2.6+0.53 mg/dl). Hypomagne-semia found mainly in cases with long-term diabetes mellitus was related to the duration of disease, net intestinal absorption rate of Mg and the incidence of diabetic retinopathy. It is suggested that hypomagnesemia might be responsible for the development of diabetic retinopathy.

Objective To characterize the effects of progesterone(P) on the expression of membrane type 1 matrix metalloproteinase (MT1 MMP) and gelatinase A activation in human osteoblast like cell strain MG 63 in order to understand the mechanism of progestin acting on the bone. Methods Semi quantitative RT PCR, Western blot, and confocal immunohistochemistry were used to study the actions of P on the expression of mRNA and protein of the MT1 MMP in cultured MG 63 cells. Zymogram of the gelatin and ELISA were performed to examine the effects of P on the activation of gelatinase A. Results Treatment with increasing dose of P in MG 63 cells caused a dose dependent increase in the expression of MT1 MMP mRNA ( P 0 05). Conclusions Our studies suggested that P might promote the bone formation by increasing MT1 MMP production in osteoblastic cells and thus played an important role in maintaining the osteogenic activity of osteoblasts and preparing the bone matrix for the subsequent bone cell migration and the deposition of new matrix.

Pancreatic islet β-cell mass is regulated by β-cell replication, nengenesis, apnptosis and cell size. β-cetl mass in diahetic patients is conspicuously less than that in normal subjects. Induction of β-cell regeneration and inhibition of β-cell apoptosis is the new target of diabetes treatment.

BACKGROUND: Transforming growth factor-β1(TGF-β1) is an important cytokine in the regulation of bone remodeling. Whether it can be used as a sensitive marker to bone turnover is incompletely understood. OBJECTIVE: To investigate the relationship of TGF-β1 with bone formation and resorption markers, and bone mineral density (BMD) at the anteroposterior lumbar spine. METHODS: Totally 663 healthy women from Changsha were analyzed, aged 20-80 years. Levels of TGF-β1, serum bone alkaline phosphatase (sBAP) and serum C-terminal cross-linked telopeptides (sCTx) were measured by ELISA, at the same time, the BMD of anteroposterior lumbar spine was measured by dual-energy x-ray absorptiometry. The associations between TGF-β1 and other indexes were analyzed. RESULTS AND CONCLUSION: The TGF-β1 levels reached a peak in the 30-39 and 40-49 years groups, which had a negative correlation with age, but no correlation with body mass index (BMI). After corrected for BMI, TGF-β1 was negatively correlated to sBAP and sCTx, but was positively correlated with BMD of spine after correction of BMI or age. TGF-β1 can act as a sensitive cytokine to reflect the changes of bone turnover.

Several key issues in the diagnosis of osteoporosis were discussed. The definition of osteoporosis and some concepts in bone fracture risk evaluation were explained, so as the methods to avoid the common misunderstandings in clinical practice. Finally, the parameters used in determination of bone metabolism and bone mass were listed, and their application and limitation were analyzed. It may help the clinicians to make correct choice of these parameters.

Bisphosphonate,as a first line medicine for treating osteoporosis,has been efficacious in reducing the incidences of fractures and some tumors.Although severe side effects such as osteonecrosis of the jaw (ONJ) and atypical fracture of femur would take place,its very low incidence does not affect the current status of bisphosphonates in the treatment of osteoporosis.

Bisphosphonates have been efficacious in preventing bone loss and reducing fractures in men and postmenopausal women with osteoporosis.Possible risks of osteonecrosis of the jaw and atypical femur fractures have been reported with bisphosphonates treatment,despite these incidences are very low.Oral bisphosphonates are associated with upper gastrointestinal side effects and iv bisphosphonates with acute phase reactions,the association of bisphosphonate use with esophageal cancer and atrial fibrillation is not well supported by current data.