[Hydrogen sulfide in cartilage and its inhibitory effect on matrix metalloproteinase 13 expression in chondrocytes induced by interlukin-1ß].

OBJECTIVE: To investigate whether endogenous hydrogen sulfide (H2S) was involved in the pathogenesis of osteoarthritis (OA) and its underlying mechanism, to detect H2S and its synthases expression in knee cartilage in patients diagnosed with different severity of OA, and to explore the transcription and expression of gene MMP-13 in chondrocytes treated with IL-1ß or H2S. METHODS: Synovial fluids of the in-patients with different severity of OA hospitalized in Peking University First Hospital were collected for measurement of H2S content using methylene blue assay. Articular cartilages of the patients who underwent knee arthroplasty were collected for the cell culture of relatively normal chondrocytes. The chondrocytes were cultured to the P3 generation and H2S molecular probes were used for detection of endogenous H2S generation in the chondrocytes. Immunocytochemistry was used to detect the localization of H2S synthases including cystathionine ß-synthase (CBS), cystathionine-γ-lyase (CSE), and mercaptopyruvate sulfurtransferase (MPST) in OA chondrocytes. Western blot was used to quantify the protein expressions of CSE, MPST, and CBS in cartilage tissues of the patients who were diagnosed with OA and underwent knee arthroplasty. The relatively normal human chondrocytes were cultured to passage 3 and then divided into 4 groups for different treatments: (1)the normal control group, no reagent was added; (2)the IL-1ß group, 5 µg/L of IL-1ß was added; (3)the IL-1ß+H2S group, 200 µmol/L of NaHS was added 30 min before adding 5 µg/L of IL-1ß;(4)the H2S group, 200 µmol/L of NaHS was added. The transcription and expression of gene MMP-13 in chondrocytes of each group were determined with Real-time PCR and Western blot, respectively. And the total NF-κB p65 and phosphorylated NF-κB p65 in chondrocytes were detected with Western blot. RESULTS: The content of H2S in the synovial fluid of degenerative knee was (14.3±3.3) µmol/L. Expressions of endogenous H2S and its synthases including CBS, CSE and MPST were present in the cytoplasm of chondrocytes.CSE protein expression in Grade 3 (defined by outerbridge grading) cartilage tissues was significantly increased as compared with that of Grade 1 cartilage tissues (1.67±0.09 vs. 1.26±0.11, P< 0.05). However, no significant difference of CBS or MPST expression among the different groups was observed. The expression of MMP-13 protein in the IL-1ßgroup was significantly higher than that in the normal chondrocytes (1.87±0.67 vs. 0.22±0.10, P<0.05), and that in the IL-1ß+H2S group was significantly decreased than that in the IL-1ß group (0.55±0.11 vs. 1.87±0.67, P< 0.05), and that in the H2S group had no significant difference compared with that in the normal control group. The transcription of MMP-13 protein in the IL-1ß group was significantly higher than that in the normal chondrocytes (31.40±0.31 vs. 1.00±0.00, P<0.05), and that in the IL-1ß+H2S group was significantly decreased than that in the IL-1ß group (24.41±1.28 vs. 31.40±0.31, P<0.05), and that in the H2S group had no significant difference compared with that in the normal control group. The total NF-κB p65 in the IL-1ß group was significantly higher than that in the normal chondrocytes (2.13±0.08 vs. 0.73±0.08, P< 0.05), and that in the IL-1ß+H2S group was significantly decreased than that in the IL-1ß group (1.24±0.13 vs. 2.13±0.08, P<0.05), and that in the H2S group had no significant difference compared with that in the normal control group. The phosphorylated NF-κB p65 in IL-1ß group was significantly higher than that in the normal chondrocytes (1.30±0.13 vs. 0.19±0.04, P<0.05), and that in IL-1ß+H2S group was significantly decreased than that in the IL-1ß group (0.92±0.26 vs. 1.30±0.13, P<0.05), and that in the H2S group had no significant difference compared with that in the normal control group. CONCLUSION: H2S affected the cartilage degeneration by partly inhibiting the degradation of extracellular matrix.

Management of scrap computer recycling in Taiwan.

It is estimated that approximately 300,000 scrap personal computers are generated each year in Taiwan [S.-L. Chang, A Study on the Scrap Computer Treatment Cost, Environment Protection Administration of Taiwan, December 1998 (in Chinese)]. The disposal of such a huge number of scrap computers presents a difficult task for the island due to the scarcity of landfills and incineration facilities available locally. Also, the hazardous materials contained (i.e., phosphor coatings of cathode ray tubes (CRTs), batteries, polychlorinated biphenyl capacitors, mercury-containing parts, liquid crystal display, high-lead content CRT funnel glass, and plastic containing flame-retardant bromine, etc.) in the scrap computers may seriously pollute the environment if they are not properly disposed of. Therefore, the EPA of Taiwan declared scrap personal computers the producer's recycling responsibility as of July 1997. Under this decree, the manufacturers, importers and sellers of personal computers have to properly recover and recycle the scrapped computers which they originally sell. On June 1, 1998, a producer responsibility recycling program for scrap computers was officially implemented in Taiwan. Under this program, consumers can bring their unwanted personal computers to the designated collection points and receive reward money. Currently, only six computer items are mandated to be recycled in this recycling program. They are notebooks, monitors, hard disks, power supplies, printed circuit boards and main frame shells. This article outlines the current scrap computer recycling system in Taiwan.

[Bony changes at the femur side after hip joint replacement: radiologic analysis of 80 hip joints].

The authors, according to Amstutz, studied the roentgenographs of 80 postoperation cases of cemented hip joint replacement performed more than two years-ago. There were bone changes in 64 cases (80%), of them, sclerosis of bone in 32 cases (40%), atrophy of bone in 25 cases (31%), absorption of bone in 24 cases (30%), thickness of bone cortex in 18 cases (22%), enlargement of medullary cavity in 12 cases (15%), periosteum reaction in 8 cases (10%), and thinness of bone cortex in 1 case (1.3%). Most of them usually occurred in the sixth month to the second year post-operation and located mainly at the 1, 4, 5 and 7 regions. The authors think that the most important cause is the unbalance of biologic stress, and other factors are elasticity and hardness of prosthesis, frictional force, cemented of the stem, etc.

Brain alveococcosis. Therapeutic experience in 14 cases.

Brain alveococcosis is a rare but threatening disease. In most cases, it metastasized to the brain with late liver or lung alveococcosis. In 14 cases, 8 were secondary, and 6 primary. Nine were treated operatively, 2 medically and 3 proved by autopsy. Eleven cases were monomassive, 2 were multifocal and 1 was extra-cerebral in the cranial base. According to our experiences, extirpation is a radical method, and can improve the cerebral function confirmed by BEAM. Long-period use of albendazole showed calcified lesions of CT and disappearance of clinical symptoms.

[Pathomorphological studies on vulvar dystrophy].

Two hundred and thirteen cases of vulvar dystrophy were analysed pathologically. The main pathological and ultrastructural changes were degeneration of cells, capillary impairment, and inability of collagenous formation. These resulted in local dystrophy and induced vulvar "Leucismus" secondarily. Its canceration rate was low. The pathogenesis of vulvar dystrophy is discussed.

Intracranial alveolar echinococcosis in China: discussion of surgical treatment.

Intracranial alveolar echinococcosis is an uncommon disease and difficult to treat. Three patients with central nervous system (CNS) involvement are reported, and the surgical treatment of the monomassive type is emphasized. The largest mass lesion reported, so far, in the literature (9.0 X 6.5 X 4.5 cm) was extirpated in one of our cases. Related problems are discussed in combination with the literature.