Evidence of a novel staphylococcal mec-encoded element (mecR) controlling expression of penicillin-binding protein 2''.

A region was identified on the methicillin resistance determinant (mec) isolated from Staphylococcus epidermidis and cloned into Staphylococcus carnosus which was responsible for a novel downregulation of the expression of methicillin resistance. The presence of this region reduced the overall expression of methicillin resistance and the synthesis of the mec-encoded penicillin-binding protein 2' (PBP 2') in S. carnosus. This region was located by Bal31 deletion mutagenesis upstream of the structural gene for PBP 2'. Deletions within this region resulted in higher levels of expression of methicillin resistance and increased levels of PBP 2' synthesis. We tentatively called this region mecR. Analysis of selected Mcr strains of Staphylococcus aureus and S. epidermidis by Southern hybridization suggested that the natural occurrence of two types of mec resistance determinants differ by the presence or absence of mecR-specific sequences.     

Retention of the posterior cruciate ligament versus the posterior stabilized design in total knee arthroplasty: a prospective randomized controlled clinical trial

Background  

Prosthetic design for the use in primary total knee arthroplasty has evolved into designs that preserve the posterior cruciate ligament (PCL) and those in which the ligament is routinely sacrificed (posterior stabilized). In patients with a functional PCL the decision which design is chosen depends largely on the favour and training of the surgeon.     

In vivo visualization of albumin degradation in the proximal tubule

Albuminuria is a key marker of renal injury and a major risk factor for cardiovascular disease. In vivo imaging techniques with fluorescent albumin have allowed visualization of its movement within the whole kidney but they could not distinguish between intact and degraded albumin. To visualize albumin degradation in proximal tubular cells in vivo we used an albumin conjugate (dye quenched (DQ)-albumin), which only fluoresces when it is degraded. In cultured proximal tubule cells, the fluorescent signal from DQ-albumin was dependent on endocytosis and lysosomal function and showed that at any time about 40% of endocytosed DQ-albumin was degraded. Significant accumulation of conventional Texas Red-labeled albumin and degraded DQ-albumin was found in rat proximal tubules 5 min after injection. Importantly, no hint of DQ-albumin was detected in the serum, suggesting that the fluorescent signal in the proximal tubules was derived from tubular degradation of intact albumin. Our study shows that DQ-albumin, together with conventional fluorescent conjugates of intact albumin, can be used to visualize albumin degradation by proximal tubules in vivo.     

Guillain-Barré syndrome in a patient with non-Hodgkin''s lymphoma.

We describe a case of Guillain–Barré syndrome (GBS) in apatient with non-Hodgkin's lymphoma (NHL). A 21-year-old woman with a newlydiagnosed stage IV high-grade lymphoma (precursor T-cell NHL according to theR.E.A.L. Classification) developed flaccid quadriparesis and bilateral facialdiplegia after three weeks of treatment with vincristine, daunorubicin,L-asparaginase and prednisolone. The clinical course and neurologicalexamination were consistent with GBS. Despite treatment with intravenousimmunoglobulins her neurological symptoms progressed. Plasmapheresis wastherefore initiated followed by intravenous immunoglobulins. After partialremission of neurologic symptoms, induction chemotherapy with cyclophosphamideand cytarabine was continued without any further complication. Three monthslater, the lymphoma was in complete remission. GBS has been described inHodgkin's disease and after bone marrow transplantation but is rare in NHL.In patients with NHL who develop neurological symptoms, drug toxicity andnervous system infiltration are the leading cause of neuropathology, but GBSshould be considered in the differential diagnosis.     

The frequency of phospholipase A2 binding of basophilic granulocytes does not decrease during bee‐venom‐specific immunotherapy

BACKGROUND: The major allergenic component of bee venom is phospholipase A2 (PLA2). METHODS: In this study, PLA2 was used to analyze and enrich PLA2-binding cells from peripheral blood by high gradient magnetic cell sorting. RESULTS: In normal donors, the frequency of allergen (PLA2)-binding cells among peripheral blood mononuclear cells (PBMC) as determined by flow cytometry is below 0.1%, whereas in bee-venom-allergic patients, PLA2-binding cells are readily detectable at frequencies of up to 2.3%. In severely bee-venom-allergic patients, many basophilic granulocytes are present, as defined by anti-CD9, CD25, and CD38 mAb, comprising up to 95% of the PLA2-binding cells. From blood of allergic and normal donors, about equal absolute numbers of allergen-binding CD19/21-positive B cells can be enriched. Severe anaphylactic reactions (Mueller grade IV) and failure of or adverse reactions during immunotherapy are associated with high numbers of circulating allergen-binding basophils. Interestingly, in the patients studied, the number of PLA2-binding basophilic granulocytes did not markedly change during rush immunotherapy and up to 6 months of maintenance immunotherapy. CONCLUSIONS: The specific and reproducible enrichment of PLA2-binding cells provides a new tool for the analysis and monitoring of effector cells in bee-venom-allergic patients with immediate-type hypersensitivity.     

Orientation of mineral crystallites and mineral density during skeletal development in mice deficient in tissue nonspecific alkaline phosphatase.

Tissue nonspecific alkaline phosphatase (TNALP) is thought to play an important role in mineralization processes, although its exact working mechanism is not known. In the present investigation we have studied mineral crystal characteristics in the developing skeleton of TNALP-deficient mice. Null mutants (n = 7) and their wild-type littermates (n = 7) were bred and killed between 8 and 22 days after birth. Skeletal tissues were processed to assess mineral characteristics (small angle X-ray scattering, quantitative backscattered electron imaging), and to analyze bone by light microscopy and immunolabeling. The results showed a reduced longitudinal growth and a strongly delayed epiphyseal ossification in the null mutants. This was accompanied by disturbances in mineralization pattern, in that crystallites were not orderly aligned with respect to the longitudinal axis of the cortical bone. Among the null mutants, a great variability in the mineralization parameters was noticed. Also, immunolabeling of osteopontin (OPN) revealed an abnormal distribution pattern of the protein within the bone matrix. Whereas in the wild-type animals OPN was predominantly observed in cement and reversal lines, in the null mutants, OPN was also randomly dispersed throughout the nonmineralized matrix, with focal densities. In contrast, the distribution pattern of osteocalcin (OC) was comparable in both types of animals. It is concluded that ablation of TNALP results not only in hypomineralization of the skeleton, but also in a severe disorder of the mineral crystal alignment pattern in the corticalis of growing long bone in association with a disordered matrix architecture, presumably as a result of impaired bone remodeling and maturation.     

苯甲酰胺类抗精神病药物的研究：6β－羟基，乙酰氧基和苯甲酰氧基－3α及β－托品烷衍生物的合成

合成了１５个３α和β－取代苯申酰氨基－６β－羟基，乙酰氧基和苯甲酰氧基－托品烷类化合物。其中化合物５ｄ，１２ｃ和１２ｄ对Ｄ－１和Ｄ－２受体都有一定的亲和作用。