Cultural responsibility in the preservation of local economic plant resources

Understanding the relationships between indigenous people and their threatened economic plants can aid the conservation effort on many levels. Understanding ethnic perceptions of the taxon is critical toin situ andex situ conservation projects and enhances the accompanying educational effort. Examples are discussed from the experience of a grassroots conservation group in southwestern United States, Native Seed/SEARCH. Four levels of economic plant vulnerability are examined among 1) wild-harvested plants, 2) husbanded wild plants, 3) domesticates, and 4) wild relatives of domesticates. Legal interpretations of endangered husbanded and domestic plants are discussed, and further documentation encouraged. Genetic dynamism of threatened indigenous crops is examined and the concept of Systems Conservation (i.e. the plant/human interactive systems) is introduced. Guidelines are offered for incorporating better cultural responsibility intoex situ conservation strategies. The concept of Biocultural Restoration is introduced with an example from an O'odham community. Examples are given of ways indigenous peoples and their knowledge can assist in the conservation effort.     

Possible mechanisms of afterripening in Xanthium seeds

Breaking dormancy in some seeds requires a period of dry storage. In the seeds of Xanthium pennsylvanicum Wallr., the process of afterripening proceeds optimally at water contents between 7 and 14%: this range of dehydration can be identified with water binding region 2, in which water is bound with low enthalpy. At water contents below 7%. Seeds remained primarily dormant over 3 years. Attempts to alter the afterripening with atmospheres of elevated nitrogen showed no effect. and with oxygen there was no consistent effect. There were no changes is osmotic value of the seed sap, or in its sugar or amino acid contents. We speculate that afterripening in Xanthium may involve some nonenxymatic reactions which remove substances which inhibit germination. Candidates for these reactions include the Amadori and Maillard reactions.     

Utilization of the ambient concentration as a criterion for steady state after exponential growth: Some culture experiments with optimum or suboptimum N nutrition

Culture experiments are described in which Plantago lanceolata L. was grown from seedling till flowering under steady state conditions of optimum or suboptimum nitrate nutrition. In the optimum treatment, plants had free access to nitrate. In two suboptimum treatments, nitrate was added with constant relative addition rates (RAR) of 0.18 or 0.10 d^–1 during the phase of constant relative uptake rates (RUR) of the plants and then with RAR's that were reduced stepwise from 0.18 to 0.07 d^–1 or 0.10 to 0.04 d^–1 when nutrient absorption gradually decreased. Reduction of the RAR's was aimed at maintenance of a balance between RAR and RUR. External nitrate concentrations were measured to monitor the reductions. In the vegetative phase, the relative growth rate (RGR) and the root weight ratio (RWR) of P. lanceolata were constant. In the reproductive phase, RGR's were constant, but lower, and RWR's decreased. Concentrations of organic-N in leaves were stable during the experimental period while those of the peduncles were lower and decreased with time. The ratio of reproductive to vegetative weight increased linearly with time. A number of plant parameters varied with N supply. ei]Section editor: T W Rufty     

Chronic Pseudomonas aeruginosa endobronchitis in rhesus monkeys: II. A histopathologic analysis

We have recently established a rhesus monkey model of chronic Pseudomonas aeruginosa (PA) endobronchitis by bronchoscopic instillation of PA-embedded agar beads. All experimental animals developed chronic neutrophilic endobronchitis similar to chronic PA endobronchitis in cystic fibrosis (CF). Histopathologic studies further confirmed similarities to chronic PA endobronchitis in CF, including marked peribronchial inflammation, epithelial damage, presence of degraded cilia and ciliary abnormalities, appearance of PA bacterial clusters, mucosal hyperplasia, goblet cell hypertrophy/hypersecretion, airway obstruction, alveolar abnormalities, bronchiectasis, and fibrosis.     

慢性缺氧对大鼠左右心室功能、心肌肌原纤维Ca~（2＋），Mg~（2＋）－ATP

模拟５０００ｍ中度缺氧时,大鼠右室功能显著加强,而左室功能加强不显著;左右心室肌原纤维Ｃａ２＋,Ｍｇ２＋－ＡＴＰ酶活性下降,肌球蛋白同功酶Ｖ２和Ｖ３百分含量增加,Ｖ１百分含量减少。８０００ｍ重度缺氧时,右室功能减弱,但无统计学意义,左室功能减弱有显著性;ＡＴＰ酶活性和同功酶的变化超过５０００ｍ组。此外,右室ＡＴＰ酶活性与ＰＡＰ呈反比且有显著性,左室ＡＴＰ酶活性与ＣＡＳＰ虽也呈反比但无显著性;右室同功酶Ｖ３百分含量与ＰＡＰ呈正比,左室同功酶Ｖ３百分含量与ＣＡＳＰ不呈比例。上述结果表明,因短期突发严重缺氧引起的心肌供氧不足对左心室心肌的直接损伤作用大于右心室心肌。     

零下低温对杂交杨树皮层膜脂组成的影响

以不耐寒的美洲黑杨（Ｐｏｐｕｌｕｓｄｅｌｔｏｉｄｅｓｃｖ．“Ｌｕｘ”Ｉ－６９／５５,父本）和耐寒性较强的欧美杨（Ｐ．ｅｕｒａｍｅｒｉｃａｎａｃｌｃｖ．Ｉ－４５／５１,母本）的４个杂交Ｆ＿１代无性系（９５杨、５５９杨、６００杨和１３８１杨）为材料,分析了零下低温寒潮前后枝条皮层的脂质组成。结果表明,寒潮影响下,皮层中磷脂含量增加而组成基本不变,膜脂脂肪酸组成的变化规律是：寒潮前脂肪酸不饱和指数（ＩＵＦＡ）值大的无性系,寒潮前后的ＩＵＦＡ值变化量小;寒潮前ＩＵＦＡ值较小的无性系,寒潮前后ＩＵＦＡ值变化量较大。本文借用力学概念,提出相对抗性概念,给出杨树无性系的相对抗性序列。序列表明Ｆ＿１代无性系的耐寒性已较不耐寒的父本提高,这与田间观察基本一致。     

Pulmonary gas exchange kinetics during exercise: physiological inferences of model order and parameters

1. 1. The ventilatory and pulmonary gas exchange responses during moderate exercise can be appropriately modelled with first-order dynamics.

2. 2. A delay term, reflecting tissue-to-lung transit time, is needed for accurate characterization, however.

3. 3. The O₂ uptake time constant ( reflects the enzymatically controlled tissue O₂ utilization.

4. 4. is appreciably longer than , consequent to the tissue CO₂ capacitance.

5. 5. As typically longer than , transient errors in alveolar and arterial blood gas tensions are predicted: small for P_CO2 but much larger for P_O2.

6. 6. At work rates above the lactate threshold, a slow and delayed component of V̇_O2 induces an additional V̇ component (“excess” V̇_O2), leading to more rapid fatigue.

7. 7. The ventilatory compensation for the metabolic acidemia at these work rates is slow, with compensation being poor for rapid-incremental exercise.

8. 8. A justifiable control model of the coupling of ventilation to metabolism must cohere with these demonstrable physiological characteristics.

肺癌患者与肺结核患者血清蛋白的电泳分析

采用SDS聚丙烯酰胺凝胶电泳银染色的方法,对58例肺癌患者和32例肺结核患者的血清蛋白进行比较分析,发现有五种特异蛋白,分别存在于A区、C区、F区和G区。肺癌组和肺结核组比较,存在极显著性差异(P<0.01),提示有早期诊断肺癌的价值,有可能成为临床诊断肺癌的一个重要参考指标。     

Duvelisib attenuates bleomycin-induced pulmonary fibrosis via inhibiting the PI3K/Akt/mTOR signalling pathway

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease that seriously threatens the health of patients. The pathogenesis of IPF is still unclear, and there is a lack of effective therapeutic drugs. Myofibroblasts are the main effector cells of IPF, leading to excessive deposition of extracellular matrix (ECM) and promoting the progression of fibrosis. Inhibiting the excessive activation and relieving autophagy blockage of myofibroblasts is the key to treat IPF. PI3K/Akt/mTOR pathway plays a key regulatory role in promoting fibroblast activation and autophagy inhibition in lung fibrosis. Duvelisib is a PI3K inhibitor that can simultaneously inhibit the activities of PI3K-δ and PI3K-γ, and is mainly used for the treatment of relapsed/refractory chronic lymphocytic leukaemia (CLL) and small lymphocytic lymphoma tumour (SLL). In this study, we aimed to examine the effects of Duvelisib on pulmonary fibrosis. We used a mouse model of bleomycin-induced pulmonary fibrosis to evaluate the effects of Duvelisib on pulmonary fibrosis in vivo and further explored the potential pharmacological mechanisms of Duvelisib in lung fibroblasts in vitro. The in vivo experiments showed that Duvelisib significantly alleviated bleomycin-induced collagen deposition and improved pulmonary function. In vitro and in vivo pharmacological experiments showed that Duvelisib dose-dependently suppressed lung fibroblast activation and improved autophagy inhibition by inhibiting the phosphorylation of PI3K, Akt and mTOR. Our results indicate that Duvelisib can alleviate the severity of pulmonary fibrosis and provide potential drugs for the treatment of pulmonary fibrosis.