Lei Pan

Disseminated infection caused by Nocardia farcinica with primary nephrotic syndrome is exceedingly rare. A 66-year-old female visited the outpatient department due to fever and fatigue who had been diagnosed as membranous nephropathy and with a long-term prednisone and immunosuppressive therapy. After lung biopsy for many times, culture from space-occupying lesion of the right lung and species identification by mass spectrometry-based methods (MALDI-TOF) revealed Nocardia farcinica. By imaging examination, space-occupying lesions from the lungs, brain, abdominal cavity and kidney were found. After 2 weeks of meropenem intravenous and up to 6 months of trimethoprim-sulfamethoxazole (TMP-SMX) therapy, our patient has remained relapse-free at that time of writing. Disseminated infection caused by Nocardia farcinica is usually subacute with complex clinical manifestations. In addition, it can be easily confused with diseases such as tumor and mycobacterial infection, and lead to fatal consequences. Therefore, we hope that we can remind clinicians considering by discussing common features of disseminated Nocardia farcinica infection.

Objectives: Osteoporosis is a prevalent condition among postmenopausal women, and lacks satisfactory therapeutic options. Hydrogen (H₂) has been shown to be effective in alleviating many diseases. This study aimed to investigate the effects of H₂on inhibiting osteoclastogenesis and bone loss in ovariectomized mice.Methods: Osteoclast differentiation from Raw264.7 cells was induced with receptor activator NF-κB ligand (RANKL) with or without 60% H₂. The number and resorption activity of osteocalsts were assessed by tartrate-resistant acid phosphatase staining and pit formation assay, respectively. The expression of osteoclast markers and NF-κB phosphorylation were detected by western blot. NF-κB nuclear translocation was assessed by immunofluorescence. NF-κB transcriptional activity was analyzed by luciferase assay. Bone loss in mice was induced by ovariectomy (OVX). OVX mice were given either regular air or 60% H₂. Bone structure was analyzed by micro-computed tomography and hematoxylin and eosin staining. Cytokine levels were measured by enzyme-linked immunosorbent assay. The data were analyzed with one-way or two-way ANOVA followed by Bonferroni post hoc tests.Results: H₂did not have any measurable effect on the proliferation of Raw264.7 cells. The number of osteoclasts and size of resorption pits of RANKL+H₂-treated cells were 3 to 4 times less than RANKL treated cells. The expression of osteoclast marker genes of RANKL+H₂-treated cells was 30% to 60% lower than RANKL-treated cells (P< 0.05). H₂markedly inhibited RANKL-induced activation, nuclear translocation, and transcriptional activity of NF-κB (P < 0.05, RANKL+H₂vs RANKL). The amount and density of trabecular bone and bone mineral density of ovariectomized mice were significantly less than sham-operated mice (P < 0.05 OVX vs sham). The amount of trabecular bone and bone mineral density of OVX mice that inhaled H₂were more than 40% higher, whereas the levels of serum proinflammatory cytokine interleukin 1β, IL-6, and tumor necrosis factor-α were more than 50% lower than those of OVX mice (P < 0.05).Conclusions: These results demonstrated that H₂could be an effective therapeutic agent of postmenopausal osteoporosis.