The causative agent of tuberculosis, Mycobacterium tuberculosis, has two chaperonin (Cpn60) proteins and one cochaperonin (Cpn10) protein. We show here that cpn60.2 and cpn10, but not cpn60.1, are essential for cell survival. A mutant lacking Cpn60.1 was indistinguishable from the wild-type organism in plate and broth culture and within murine macrophages, although it showed increased sensitivity to high temperature (55°C). However, infection of mice with the ⌬cpn60.1 mutant revealed a major difference from the wild-type organism. In spite of having equal numbers of bacteria in infected sites, the ⌬cpn60.1 mutant failed to produce granulomatous inflammation in either mice or guinea pigs. This was associated with reduced cytokine expression in infected animals and macrophages. Cell wall lipid acid composition was not altered in the mutant strain. Thus, it appears that Cpn60

Femur-derived osteoblasts cultured from rat femora were loaded with Fluo-3 using the AM ester. A quantifiable stretch was applied and [Ca(2+)]i levels monitored by analysis of fluorescent images obtained using an inverted microscope and laser scanning confocal imaging system. Application of a single pulse of tensile strain via an expandable membrane resulted in immediate increase in [Ca(2+)]i in a proportion of the cells, followed by a slow and steady decrease to prestimulation levels. Application of parathyroid hormone (10(-6) M) prior to mechanical stimulation potentiated the load-induced elevation of [Ca(2+)]i. Mechanically stimulating osteoblasts in Ca(2+)-free media or in the presence of either nifedipine (10 microM; L-type Ca(2+)-channel blocker) or thapsigargin (1 microM; depletes intracellular Ca(2+) stores) reduced strain-induced increases in [Ca(2+) ]i. Furthermore, strain-induced increases in [Ca(2+)]i were enhanced in the presence of Bayer K 8644 (500 nm), an agonist of L-type calcium channels. The effects of mechanical strain with and without inhibitors and agonists are described on the total cell population and on single cell responses. Application of strain and strain in the presence of the calcium-channel agonist Bay K 8644 to periosteal-derived osteoblasts increased levels of the extracellular matrix proteins osteopontin and osteocalcin within 24 h postload. This mechanically induced increase in osteopontin and osteocalcin was inhibited by the addition of the calcium-channel antagonist, nifedipine. Our results suggest an important role for L-type calcium channels and a thapsigargin-sensitive component in early mechanical strain transduction pathways in osteoblasts.

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Ovarian dysgerminomas are rare entity and account for only about 2% of all malignant ovarian neoplasm. The aim of this study was to evaluate the clinicopathologic characteristics, treatment, long-term survival, and fertility outcome of women diagnosed with ovarian dysgerminoma at our institution. Sixty-five women with histologically proven pure ovarian dysgerminoma were identified in this retrospective study. They were treated at King Faisal Specialist Hospital, Riyadh; Saudi Arabia between 1976 and 2010. The median age was 20 years. The most frequent symptoms at presentation were abdominal pain and abdominal/pelvic mass. Thirty-three patients (50.7%) presented with stage I, 2 (3.1%) had stage II, 22 (33.8%) had stage III, and 4 (6.2%) had stage IV (4 unknown stage). Unilateral oophorectomy was performed in 50 patients (76.9%) while bilateral oophorectomy±hysterectomy was done in 12 patients (18.4%). Three patients had biopsy only. Forty patients (61.5%) received only chemotherapy, and 4 patients (6.2%) received radiotherapy alone. Recurrence was observed in 6 patients (9.2%). With median follow-up of 54 months, the 5-year disease-free survival (DFS) and overall survival (OS) were 88 and 95%, respectively. On univariate analysis, adjuvant chemotherapy was independent better prognostic factor for DFS (HR, 0.09; 95% CI, 0.01-0.84; P=0.034). Of the 50 patients treated with fertility-sparing surgery, 16 patients (32%) achieved pregnancy with 14 live births. Patients with pure ovarian dysgerminoma have excellent long-term outcome. There is no difference at outcome between fertility-sparing and nonconservative surgeries. Adjuvant chemotherapy was associated with significant improvement in DFS. It is possible to maintain good reproductive function after conservative surgery followed by chemotherapy in our series.

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