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J Landes

Publications and source records attributed to J Landes.

At least 19 recordsLinked to original sources
PubMed2003

Quantitative assessment of angiogenesis in murine antigen-induced arthritis by intravital fluorescence microscopy.

Inhibition of angiogenesis might be a therapeutic approach to prevent joint destruction caused by the overgrowing synovial tissue during chronic joint inflammation. The aim of this study was to investigate angiogenesis in the knee joint of mice with antigen-induced arthritis (AIA) by means of intravital microscopy. In 14 mice (C57BL6/129Sv) intravital microscopic assessment was performed on day 8 after AIA induction in two groups (controls, AIA). Synovial tissue was investigated by intravital fluorescence microscopy using FITC-dextran (150 kD). Quantitative assessment of vessel density was performed according to the following categories: functional capillary density (FCD, vessels <10 microm in diameter), functional vessel density (FVD, vessels >10 microm) and FVD of vessels with angiogenic criteria (convoluted vessels, abrupt changes of diameter, vessels which are generated by sprouting and progressively pruned and remodelled). Microvessel count was performed using immunohistochemistry. There was no significant difference in FCD between the control group (337 +/- 9 cm/cm2; mean +/- SEM) and the AIA group (359 +/- 13 cm/cm2). The density of vessels larger than 10 microm diameter was significantly increased in animals with AIA (135 +/- 10 vs. 61 +/- 5 cm/cm2 in control). The density of blood vessels with angiogenic criteria was enhanced in arthritic animals (79 +/- 17 vs. 12 +/- 2 cm/cm2 in control). There was a significant increase in the microvessel count in arthritic animals (297 +/- 25 vs. 133 +/- 16 mm(-2) in control). These findings demonstrate that angiogenesis in murine AIA can be assessed quantitatively using intravital microscopy. Further studies will address antiangiogenic strategies in AIA.

Animals↗
PubMed2003

Ileoileal intussusception caused by a Ewing sarcoma tumour. An unusual case report.

Intussusception typically occurs in childhood, presenting with a well-known medical history and clinical symptoms. Pathologically, a "leading point" may be attributed to lymphadenomatosis, polyps, or a tumour. In older patients and adolescents, the diagnosis can be complicated due to the lower incidence and variable subacute symptoms. We report on an 18-year-old patient with increasing abdominal discomfort over several weeks. External diagnostics showed no pathological signs or were misinterpreted as a malfunction of intestinal motility. The patient experienced increasing colics, recurrent vomiting, dehydration and weight loss. Finally he was transferred to our paediatric surgical department and laparotomy had to be performed for the clinical and radiological signs of an ileus. An ileoilealic intussusception was found, caused by a small bowel tumour, which almost completely obstructed the intestinal lumen. It was resected and bowel continuity was re-established. Histopathology revealed a very rare, highly malignant mesenchymal Ewing sarcoma, infiltrating the complete bowel wall. After the postoperative course, the patient was transferred to our oncological department for chemotherapy. In older children or young adults, intestinal malignancies are extremely rare. Nevertheless, if these patients suffer from unspecific complaints of chronic intestinal obstruction, a tumour must be ruled out. A Ewing sarcoma may be responsible for an intussusception.

Adolescent↗
PubMed2002

[The femoral neck fracture in the elderly patient - cemented or cementless hip arthroplasty?].

This is a report on the treatment results of femoral neck fractures with a cemented (group 1) and cementless (group 2) type of hip prosthesis, resp. 72 patients were enrolled. 35 patients were treated with a cemented hip prosthesis (mean age: 78 years), and 37 patients with a cementless modular hip prosthesis (mean age: 77 years). In the cemented group we observed 5 cases of hypotension during insertion of the prosthesis in the femoral shaft. One of these patients required mechanical resuscitation during surgery. In the second group 3 cases of proximal femur fissure and one case of distal femoral fracture were recorded. One year after surgery 43 patients presented for follow up evaluation (cemented group: n = 24; cementless group: n = 19). Both groups revealed comparable results according to the Harris Hip Score (75 versus 78,3 points). No prosthesis loosening was observed in either group. In our view the cemented hip prosthesis is the treatment of choice for femoral neck fractures among the old and very old, if no stabile osteosynthesis can be performed. Patients with cardiopulmonary risk factors, however, may profit from cementless hip arthroplasty to avoid the well known cardiodepression during surgery.

Aged↗
PubMed2001

Exacerbation of antigen-induced arthritis in inducible nitric oxide synthase-deficient mice.

OBJECTIVE: Inhibition of nitric oxide (NO) produced by inducible NO synthase (iNOS) is suggested to be beneficial in experimental arthritis. Although NO is important for the integrity of the microcirculation, the effects of inhibition of iNOS on the synovial microcirculation are not currently known. This study investigated the synovial microcirculation and leukocyte-endothelial cell interactions in iNOS-deficient mice with antigen-induced arthritis (AIA) and compared these findings with disease severity. METHODS: Fourteen homozygous iNOS-/- and 14 iNOS+/+ mice were used. The severity of AIA was assessed by measuring knee joint swelling and by histologic scoring. The number of rolling and adherent leukocytes was quantitatively analyzed in synovial microvessels using intravital microscopy of intraarticular synovial tissue. Nitrite/nitrate concentrations were measured, and the expression of iNOS, E- and P-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 (VCAM-1) was assessed by immunohistochemistry. RESULTS: In iNOS+/+ animals with AIA, the plasma concentration of nitrite/nitrate was increased 3-fold and iNOS expression was detected in cells of the joint. Swelling of the knee joint as well as leukocyte infiltration were enhanced in the iNOS-/- arthritic animals compared with iNOS+/+ mice with AIA. AIA-associated leukocyte-endothelial cell interaction in synovial postcapillary venules was more pronounced in iNOS-/-, compared with iNOS+/+, arthritic mice. A strong expression of P-selectin and VCAM-1 was observed in the iNOS-/- arthritic mice only. CONCLUSION: These data suggest that NO production by iNOS in vivo has antiinflammatory effects in experimental arthritis, by mediating a reduction in leukocyte adhesion and infiltration.

Animals↗
PubMed2000

[Treatment of per- and subtrochanteric femoral fractures by gamma nails and modular hip prostheses. Differential indications and results].

From January 1997 to August 1998 all stable and nonstable trochanteric femoral fractures (n = 72) were treated routinely by gamma nail using the correct operative technique. Patients showing additional osteoarthritis of the hip in radiographs hip replacement was performed by a cementless modular femoral hip prostheses from January 1996 to August 1998 (n = 28). Follow up period was 6 to 18 months. Operation time and blood loss were higher using the prostheses. However complications and lethality (< 5%) were not different during postoperative course. In each group three operative technical complications occurred. Using a modified Harris Hip Score (without range of motion, contractions) the score was decreased non significant comparing both groups first of all in unstable fractures until follow up. In each group one revision (loosening of prostheses, excessive shortening of femoral neck) was necessary. Using the correct operative technique, the gamma nail proved to be a save device with good outcome. Outcome using modular prostheses is comparable to gamma nail. Therefore the use of modular prostheses is justified in case of osteoarthrosis and in some cases of very unstable fracture.

Adult↗
PubMed1979

Release of alkaline phosphatase activity by aqueous-ether treatment of whole cells of Serratia marcescens.

The effect of aqueous-ether treatment according to the method of Ribi et al. (1961) on the release of alkaline phosphatase from cells of two strains of Serratia marcescens was studied. By this method, lipopolysaccharide-protein (endotoxin) complexes associated with alkaline phosphatase activities were released from both strain 08 and strain Bizio. SDS-polyacrylamide gel electrophoresis followed by enzymatic assay showed the presence of two active components in each strain. Fractions released from strain 08 contained alkaline phosphatase A (140,000 dalton) and alkaline phosphatase B (110,000) daltons) while those from strain Bizio contained alkaline phosphatase A' (190,000 daltons) and alkaline phosphatase B (110,000 daltons). Although it is known that saline plays a role in the release of alkaline phosphatase activities from cell envelope of Gram-negative bacteria the presence of saline in the extracting medium affects only slightly the chemical composition and not at all on the enzymatic nature of the released components. By comparing the enzymatic profiles of the materials released by other techniques, such as polymyxin B treatment and osmotic shock, it appears that alkaline phosphatase activities released by aqueous-ether treatment of whole cells of S. marcescens originate from the periplasmic space.

Alkaline Phosphatase↗
PubMed1975

[A case of leiomyoma of the iris].

A case of leiomyoma of the iris confirned to the nasal quadrant in a 64 year old man is presented. The clinical and histopathological characteristics of this observation confirms the classical data about this rare tumor : clinical silence, discovery through a complication, difficult diagnosis, therapeutical value of the surgical biopsy and good prognosis.

Eye Neoplasms↗