BackgroundLower limb lymphedema (LLL) is a chronic and incapacitating condition afflicting patients who undergo lymphadenectomy for gynecologic cancer. This study aimed to identify risk factors for LLL and to develop a prediction model for its occurrence.MethodsPelvic lymphadenectomy (PLA) with or without para-aortic lymphadenectomy (PALA) was performed on 366 patients with gynecologic malignancies at Yaizu City Hospital between April 2002 and July 2014; we retrospectively analyzed 264 eligible patients. The intervals between surgery and diagnosis of LLL were calculated; the prevalence and risk factors were evaluated using the Kaplan-Meier and Cox proportional hazards methods. We developed a prediction model with which patients were scored and classified as low-risk or high-risk.ResultsThe cumulative incidence of LLL was 23.1% at 1 year, 32.8% at 3 years, and 47.7% at 10 years post-surgery. LLL developed after a median 13.5 months. Using regression analysis, body mass index (BMI) ≥25 kg/m2 (hazard ratio [HR], 1.616; 95% confidence interval [CI], 1.030–2.535), PLA + PALA (HR, 2.323; 95% CI, 1.126–4.794), postoperative radiation therapy (HR, 2.469; 95% CI, 1.148–5.310), and lymphocyst formation (HR, 1.718; 95% CI, 1.120–2.635) were found to be independently associated with LLL; age, type of cancer, number of lymph nodes, retroperitoneal suture, chemotherapy, lymph node metastasis, herbal medicine, self-management education, or infection were not associated with LLL. The predictive score was based on the 4 associated variables; patients were classified as high-risk (scores 3–6) and low-risk (scores 0–2). LLL incidence was significantly greater in the high-risk group than in the low-risk group (HR, 2.19; 95% CI, 1.440–3.324). The cumulative incidence at 5 years was 52.1% [95% CI, 42.9–62.1%] for the high-risk group and 28.9% [95% CI, 21.1–38.7%] for the low-risk group. The area under the receiver operator characteristics curve for the prediction model was 0.631 at 1 year, 0.632 at 3 years, 0.640 at 5 years, and 0.637 at 10 years.ConclusionBMI ≥25 kg/m2, PLA + PALA, lymphocyst formation, and postoperative radiation therapy are significant predictive factors for LLL. Our prediction model may be useful for identifying patients at risk of LLL following lymphadenectomy. Providing an intensive therapeutic strategy for high-risk patients may help reduce the incidence of LLL and conserve the quality of life.

This study focuses on the function of the gene praR that encodes a putative transcription factor in Azorhizobium caulinodans ORS571, a microsymbiont of Sesbania rostrata. The praR gene is a homolog of the phrR gene of Sinorhizobium medicae WSM419, and the praR and phrR homologs are distributed throughout the class Alphaproteobacteria. The growth and nitrogen fixation activity of an A. caulinodans praR deletion mutant in the free-living state were not significantly different from those of the wild-type strain. However, the stem nodules formed by the praR mutant showed lower nitrogen fixation activity than the wild-type stem nodules. Microscopy revealed that infected host cells with an oval or elongated shape were observed at early stages in the nodules formed by the praR mutant, but these infected cells gradually fell into two types. One maintained an oval or elongated shape, but the vacuoles in these cells gradually enlarged and the bacteria gradually disappeared. The other cells were shrunken with bacteria remaining inside. Microarrays revealed that genes homologous to the reb genes of Caedibacter taeniospiralis were highly expressed in the praR mutant. Furthermore, the stem nodules formed by an A. caulinodans mutant with a deletion of praR and reb-homologous genes showed high nitrogen fixation activity, comparable to that of the wild-type stem nodules, and were filled with oval or elongated host cells. These results suggest that PraR controls the expression of the reb-homologous genes and that high expression of reb-homologous genes causes aberrance in A. caulinodans-S. rostrata symbiosis.

The whole-genome sequence of the endosymbiotic bacterium Azorhizobium caulinodans ORS571, which forms nitrogen-fixing nodules on the stems and roots of Sesbania rostrata, was recently determined. The sizes of the genome and symbiosis island are 5.4 Mb and 86.7 kb, respectively, and these sizes are the smallest among the sequenced rhizobia. In the present study, a whole-genome microarray of A. caulinodans was constructed, and transcriptomic analyses were performed on free-living cells grown in rich and minimal media and in bacteroids isolated from stem nodules. Transcriptional profiling showed that the genes involved in sulfur uptake and metabolism, acetone metabolism, and the biosynthesis of exopolysaccharide were highly expressed in bacteroids compared to the expression levels in free-living cells. Some mutants having Tn5 transposons within these genes with increased expression were obtained as nodule-deficient mutants in our previous study. A transcriptomic analysis was also performed on free-living cells grown in minimal medium supplemented with a flavonoid, naringenin, which is one of the most efficient inducers of A. caulinodans nod genes. Only 18 genes exhibited increased expression by the addition of naringenin, suggesting that the regulatory mechanism responding to the flavonoid could be simple in A. caulinodans. The combination of our genome-wide transcriptional profiling and our previous genome-wide mutagenesis study has revealed new aspects of nodule formation and maintenance.The symbiosis between rhizobia and legumes results in the formation of nitrogen-fixing nodules. The symbiotic interaction begins with the induction of bacterial nod genes by flavonoids secreted from the plant roots (8). The nod genes encode proteins that synthesize the nodulation (Nod) factor, which initiates many developmental changes, such as root hair curling and root cell division required for the formation of the nodule primordium in the host plant early during the nodulation process (8,24,50). Bacteria are entrapped in the curled root hair and subsequently infect the root hair through infection threads made of the plant cell wall. Upon release from the infection threads, bacteria invade the plant cell cytoplasm, where they differentiate into bacteroids and provide ammonium to the host plant by reducing atmospheric dinitrogen in exchange for carbon and amino acid compounds (16,49,53). It has been deduced that multiple stages exist in the establishment of nitrogen-fixing symbiosis. To identify novel genes involved in various stages of symbiosis, transcriptomic studies based on complete genome sequences were performed using Sinorhizobium (1, 2, 5, 9), Mesorhizobium (71), and Bradyrhizobium (10,42,54).Azorhizobium caulinodans ORS571 is a microsymbiont of Sesbania rostrata (18)(19)(20). Nitrogen-fixing nodules are formed by A. caulinodans on the stems as well as on the roots of S. rostrata. Stem nodules occur at the site of adventitious root primordia located on the stems after crack-entry invasion by A. caulinodans (70). During...

The resistance of mouse pregnancy to iNKT cell stimulation by OCH and the prevention of AGC-induced fetal loss by IL-4 were demonstrated. In pregnancy, the regulation of Th1/Th2 polarity by iNKT cells is a key to healthy fetal growth.

The findings in this study suggest that the inhibitory effects of TSS on pregnancy loss may involve immune modulation of iNKT cells during early pregnancy.