Foliar nutrient resorption stoichiometry and microbial phosphatase catalytic efficiency together alleviate the relative phosphorus limitation in forest ecosystems.

Understanding how plants adapt to spatially heterogeneous phosphorus (P) supply is important to elucidate the effect of environmental changes on ecosystem productivity. Plant P supply is concurrently controlled by plant internal conservation and external acquisition. However, it is unclear how climate, soil, and microbes influence the contributions and interactions of the internal and external pathways for plant P supply. Here, we measured P and nitrogen (N) resorption efficiency, litter and soil acid phosphatase (AP) catalytic parameters (Vmax(s) and Km ), and soil physicochemical properties at four sites spanning from cold temperate to tropical forests. We found that the relative P limitation to plants was generally higher in tropical forests than temperate forests, but varied greatly among species and within sites. In P-impoverished habitats, plants resorbed more P than N during litterfall to maintain their N : P stoichiometric balance. In addition, once ecosystems shifted from N-limited to P-limited, litter- and soil-specific AP catalytic efficiency (Vmax(s) /Km ) increased rapidly, thereby enhancing organic P mineralization. Our findings suggested that ecosystems develop a coupled aboveground-belowground strategy to maintain P supply and N : P stoichiometric balance under P-limitation. We also highlighted that N cycle moderates P cycles and together shape plant P acquisition in forest ecosystems.

Role of Ca²âº in Inhibiting Ischemia-Induced Apoptosis of Parathyroid Gland Cells in New Zealand White Rabbits.

BACKGROUND Hypoparathyroidism is a common complication after thyroidectomy. Calcium supplementation can relieve these symptoms, but it is not clear whether it can protect the parathyroid glands. This study aimed to verify whether Ca²âº inhibits the apoptosis of parathyroid cells following ischemic injury. MATERIAL AND METHODS A rabbit model of parathyroid gland ischemic injury was established. The blood calcium concentrations were measured by colorimetry. The parathyroid hormone (PTH) levels were measured by enzyme-linked immunosorbent assay (ELISA). The parathyroid tissues were observed by hematoxylin and eosin (H&E) staining and the TdT-mediated dUTP nick-end labeling (TUNEL) assay. Western blotting was used to quantify the levels of the following proteins: caspase-3 and p38 MAP Kinase (p38 MAPK). RESULTS This study demonstrates that apoptosis can be a part of the pathological changes associated with parathyroid ischemic injury. Calcium supplementation inhibited the apoptosis of parathyroid cells following ischemic injury. There were no significant differences among the serum calcium levels from the Sham operation (Sham), the Control group (CG), or the Calcium supplementation group (CSG) after 24 h, 72 h, and 168 h of treatment. PTH levels in the CG were significantly higher than in the CSG at 24 h and 72 h after treatments. The apoptosis rate of parathyroid cells from rabbits in the CSG was significantly lower than that of those from rabbits in the CG at 24 h and 72 h after the treatment. Calcium supplementation inhibited p38 MAPK and caspase-3 expression. CONCLUSIONS This study demonstrates that calcium supplementation inhibited the apoptosis of parathyroid cells following ischemic injury.

Survival analysis of patients with non-small cell lung cancer who underwent surgical resection following 4 lung cancer resection guidelines.

BACKGROUND: To compare survival of patients with non-small cell lung cancer (NSCLC) who underwent surgical resection and lymph node sampling based on guidelines proposed by the American College of Surgeons Oncology Group (ACOSOG), National Comprehensive Cancer Network (NCCN), the OSI Pharmaceutical RADIANT trial, and the International Association for the Study of Lung Cancer (IASLC). METHODS: Medical records of patients with NSCLC who underwent surgical resection from 2001 to 2008 at our hospital were reviewed. Staging was according to the 7th edition of the AJCC TNM classification of lung cancer. Patients who received surgical resection following the IASLC, ACOSOG, RADIANT or NCCN resection criteria were identified. RESULTS: A total of 2,711 patients (1803 males, 908 females; mean age, 59.6 ± 9.6 years) were included. Multivariate Cox proportional hazards regression analysis indicated that increasing age, adenosquamous histology, and TNM stage II or III were associated with decreased overall survival (OS). Univariate analysis and log-rank test showed that surgical resection following the guidelines proposed by the IASLC, NCCN, ACOSOG, or RADIANT trial was associated with higher cumulative OS rates (relative to resection not following the guidelines). Multivariate analysis revealed that there was a significant improvement in OS only when IASLC resection guidelines (complete resection) were followed (hazard ratio=0.84, 95% confidence interval 0.716 to 0.985, P=0.032). CONCLUSIONS: Surgical resection following the criteria proposed by IASLC, NCCN, ACOSOG, or the RADIANT trial was associated with a higher cumulative OS rate. However, significant improvement in OS only occurred when IASLC resection guidelines were followed.

[Clinical observation of XELOX (Capecitabine puls Oxaliplatin): an adjuvant chemotherapy regimen used in stage III colorectal cancer].

OBJECTIVE: To evaluate the efficacy and safety of an adjuvant chemotherapy regimen: XELOX (Capecitabine puls Oxaliplatin) used after curative resection for stage III colorectal cancer. METHODS: From Jan. 1998 to Jan. 2004, 256 cases with stage III colorectal cancer randomized received de Gramont, modified FOLFOX4 (mFOLFOX4) and XELOX regimens. The 3-year disease-free survival (DFS) and overall survival (OS) were compared within the three groups and relative prognosis factors within mFOLFOX4 and XELOX groups. Therapeutic adverse events were recorded and analyzed with Kaplan-Meier test. RESULTS: 98, 87 and 71 cases were respectively enrolled in the de Gramont, mFOLFOX4 and XELOX groups, mFOLFOX4 and XELOX had superior efficacy compared with de Gramont regimen. The two former could significantly improve 3-year DFS (79.7% vs. 66.2%, P = 0.015; 81.5% vs. 66.2%, P = 0.004) and medium survival time (40.2 mon vs. 37.8 mon, P = 0.024; 41.4 mon vs. 37.8 mon, P = 0.014). Meanwhile they could respectively decrease the ratio of recurrence risk by 18.0% (P = 0.024) and 21.0% (P = 0.003). The relative benefit of mFOLFOX4 versus XELOX didn't differ for 3-year DFS [hazard ratio (HR): 0.84, 95% confidence interval (CI): 0.79-1.12, P = 0.13] and OS (HR: 0.87, 95% CI: 0.84-1.06, P = 0.54). In the analysis of DFS in relative prognosis factors, XELOX had a better trend of survival advantage. mFOLFOX4 had higher adverse events within these regimens, especially in grade 3 or 4 neutropenia and peripheral neurologic adverse events. CONCLUSION: XELOX maintains its efficacy and safety ratio in advanced colorectal cancer. Patients have good tolerance and compliance. The regiment is deserves to be applied in clinical treatment. Oxaliplatin;