The evolution of parasitism from mutualism in wasps pollinating the fig, Ficus microcarpa, in Yunnan Province, China.

Theory identifies factors that can undermine the evolutionary stability of mutualisms. However, theory's relevance to mutualism stability in nature is controversial. Detailed comparative studies of parasitic species that are embedded within otherwise mutualistic taxa (e.g., fig pollinator wasps) can identify factors that potentially promote or undermine mutualism stability. We describe results from behavioral, morphological, phylogenetic, and experimental studies of two functionally distinct, but closely related, Eupristina wasp species associated with the monoecious host fig, Ficus microcarpa, in Yunnan Province, China. One (Eupristina verticillata) is a competent pollinator exhibiting morphologies and behaviors consistent with observed seed production. The other (Eupristina sp.) lacks these traits, and dramatically reduces both female and male reproductive success of its host. Furthermore, observations and experiments indicate that individuals of this parasitic species exhibit greater relative fitness than the pollinators, in both indirect competition (individual wasps in separate fig inflorescences) and direct competition (wasps of both species within the same fig). Moreover, phylogenetic analyses suggest that these two Eupristina species are sister taxa. By the strictest definition, the nonpollinating species represents a "cheater" that has descended from a beneficial pollinating mutualist. In sharp contrast to all 15 existing studies of actively pollinated figs and their wasps, the local F. microcarpa exhibit no evidence for host sanctions that effectively reduce the relative fitness of wasps that do not pollinate. We suggest that the lack of sanctions in the local hosts promotes the loss of specialized morphologies and behaviors crucial for pollination and, thereby, the evolution of cheating.

Heme oxygenase-1 attenuates seawater drowning-induced acute lung injury through a reduction in inflammation and oxidative stress.

OBJECTIVE: Heme oxygenase-1 (HO-1) plays a critical protective role in various insults-induced acute lung injury (ALI) through its strong anti-inflammatory, anti-oxidant, and anti-apoptotic properties, but its protective role and mechanism on seawater aspiration-induced acute lung injury remains unclear. This study aimed to explore the therapeutic potential and mechanism of HO-1 to attenuate seawater aspiration-induced ALI in vivo and in vitro. METHODS: The viability and invasion of A549 cell were analyzed through cell counting kit-8 and lactate dehydrogenase release assay; the transcriptional level of inflammatory cytokines (TNF-α, IL-6, IL-8 and MCP-1) and cell proliferation-related cytokines (FoxM1, Ccnb1 and Cdc25C) in seawater-treated A549 cell were tested by qPCR; apoptotic cells were analyzed by flow cytometryd; HO-1mRNA and protein were determined by qPCR and western blotting; the fluorescent indicators (DCFH-DA, dihydroethidium, MitoSox Red and Fluo-4) were used to monitor generation of ROS and mitochondrial function. The lung wet/dry weight radio and lactate dehydrogenase activity, Sirius red staining, TUNEL assay and immunohistochemical staining with anti-pan Cytokeratin antibody were analyzed in seawater-drowning mice. The role of HO-1 on seawater-drowning pulmonary injury was explored via HO-1 activity inhibitors (Zinc protoporphyrin) in vitro and in vivo. RESULTS: Seawater exposure decreased the cellular viability, increased the production of pro-inflammatory cytokines (IL-6, IL-8 and TNF-α), induced cellular apoptosis and inhibited the expression of cell proliferation-related cytokines (FoxM1, Ccnb1 and Cdc25C). Moreover, seawater exposure led to mitochondrial dysfunction in A549 cells. Supplement of HO-1 sepcific inducer (heme) or its catalytic product (biliverdin) significantly attenuated seawater-induced A549 damage and promoted cell proliferation. However, Zinc protoporphyrin abolished the beneficial effects of HO-1 on seawater drowning-induced pulmonary tissue injury. CONCLUSION: HO-1 attenuates seawater drowning-induced lung injury by its anti-inflammatory, anti-oxidative, and anti-apoptosis function.

PPARα Mediates the Hepatoprotective Effects of Nutmeg.

Nutmeg is a Traditional Chinese Medicine used to treat gastrointestinal diseases. Some reports have indicated that nutmeg has hepatoprotective activity. In this study, a thioacetamide (TAA)-induced acute liver injury model in mice was used to explore the mechanism of the protective effects of nutmeg extract (NME), including its major bioactive component myrislignan. The results indicated that NME could effectively protect TAA-induced liver damage as assessed by recovery of increased serumtransaminases, decrease in hepatic oxidative stress, and lower hepatic inflammation. Metabolomics analysis further revealed that treatment with NME led to the recovery of a series of lipids including lysophosphatidylcholines that were decreased and a lowering of acylcarnitines that were increased in mouse plasma and liver after TAA exposure. Gene expression analysis demonstrated that the hepatoprotective effect of NME was achieved by modulation of the peroxisome proliferator-activated receptor alpha (PPARα) as well as the decrease in oxidative stress. NME could not protect from TAA-induced liver injury in Ppara-null mice, suggesting that its protective effect was dependent on PPARα. Myrislignan, a representative neolignan in nutmeg, showed potent protective activity against TAA-induced liver toxicity. These data demonstrate that nutmeg alleviates TAA-induced liver injury through the modulation of PPARα and that the lignan compounds in nutmeg such as myrislignan partly contributed to this action.

Effects of combined therapy of Xuezhikang Capsule and Valsartan on hypertensive left ventricular hypertrophy and heart rate turbulence.

OBJECTIVE: To observe the effect of combined therapy with Xuezhikang Capsule (XZK) and Valsartan on left ventricular hypertrophy (LVH) and heart rate turbulence (HRT) in hypertensive patients. METHODS: Ninety primary hypertensive patients with LVH were randomly assigned to three groups. Basic treatment, including aspirin, beta-blockers, calcium antagonists, etc. were administered to all patients. Additionally, Valsartan (VS, 80 mg once a day) was given to the 30 patients in the VS group. Valsartan (in the same dosage) and XZK (600 mg, twice a day) were given to the 32 patients in the Chinese medicine (CM) group, while none was given to the 28 patients in the control group. The therapeutic course lasted for 24 months. Changes in left ventricular mass index (LVMI) measured by cardiac ultrasonic indices, HRT parameters, including the original heart rate (TO) and slope coeffificient (TS), systolic and diastolic blood pressures (SBP and DBP), as well as blood cholesterol level (TC) were measured before and after treatment. RESULTS: After treatment, TO and LVMI were lowered, while TS increased in both the VS group and the CM group (P<0.01), but changed insignificantly in the control group. Significant differences between the CM group and the control group were shown in terms of TO, LVMI, SBP, DBP and TS (P<0.01); and between the CM group and the VS group in terms of TO, LVMI and TS (P<0.01). Moreover, HRT parameters showed an evident correlation with LVMI (r=0.519-0.635, P<0.01). CONCLUSION: Combined therapy with XZK and Valsartan can improve hypertensive LVH and HRT parameters, and lessen the damage on the autonomous nervous system.

Gender difference in blood pressure responses to dietary sodium intervention in the GenSalt study.

OBJECTIVE: To examine factors related to blood pressure (BP) responses to dietary sodium and potassium interventions. METHODS: We conducted a dietary feeding study that included a 7-day low-salt intervention (51.3 mmol sodium/day), a 7-day high-salt intervention (307.8 mmol sodium/day), and a 7-day high-salt and potassium-supplementation (60 mmol potassium/day) intervention among 1906 study participants in rural China. The BP was measured nine times during the 3-day baseline observation and during the last 3 days of each intervention phase using a random-zero sphygmomanometer. RESULTS: The BP responses to low-sodium intervention were significantly greater in women than in men: -8.1 [95% confidence interval (-8.6 to -7.6)] versus -7.0 (-7.5 to -6.6) mmHg for systolic and -4.5 (-4.9 to -4.1) versus -3.4 (-3.8 to -3.0) mmHg for diastolic. Likewise, BP responses to high-sodium interventions were significantly greater in women than in men: 6.4 (5.9-6.8) versus 5.2 (4.8-5.7) mmHg for systolic and 3.1 (2.7-3.5) versus 1.7 (1.4-2.1) mmHg for diastolic (all P < 0.001). In addition, systolic BP responses to sodium interventions increased with age, and both systolic and diastolic BP responses to sodium interventions increased with baseline BP levels. BP responses to potassium supplementation also increased with baseline BP levels. CONCLUSION: These results suggest that female gender, older age, and hypertension increase the sensitivity to dietary sodium intervention. Furthermore, low dietary sodium intake may be more effective in reducing BP among these subgroups.

Lung autotransplantation technique in the treatment for central lung cancer of upper lobe.

AIM: To assess the feasibility and benefit of lung autotransplantation technique in surgical treatment for central lung cancer of upper lobe which could not tolerate pneumonectomy. METHODS: From August 2000 to August 2006 seven patients, who were proved to be malignant pathologically through fiber-bronchoscope before operation and could not tolerate pneumonectomy, underwent lung autotransplantations. Double-sleeve resection of the right upper and middle bilobectomy (or left upper lobectomy) and involved pulmonary artery was performed firstly. Because the length of resected bronchus or pulmonary artery involved by tumor was too long to perform tension-free anastomosis, we transplanted the inferior pulmonary vein to the proximal stump of the superior pulmonary vein. The bronchus and pulmonary artery were anastomosed in turn. Then radical hilar and mediastinal lymphadenectomy was performed. RESULTS: Until August 2006, among the seven patients who underwent lung autotransplantations, five patients had been free of tumor recurrence for 2 to 73 months with good quality of life. Radioisotope scanning of the replanted lobe of one patient revealed normal perfusion 6 years postoperatively. One patient received resection of the replanted lobe because of pulmonary vein thrombus on the second day after transplantation, and died of respiratory failure caused by pulmonary relapse on 15th month postoperatively. Another patient died of brain metastases 31 months postoperatively. No anastomotic stoma fistula occurred in these seven patients. CONCLUSION: Lung autotransplantation is an alternative technique for pulmonary preservation for patients with centrally placed tumor of the upper lobe, whose pulmonary function is too poor to undergo pneumonectomy.