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1.
Plant Biol (Stuttg) ; 22(4): 601-614, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32109335

ABSTRACT

Intraspecific trait variation (ITV; i.e. variability in mean and/or distribution of plant attribute values within species) can occur in response to multiple drivers. Environmental change and land-use legacies could directly alter trait values within species but could also affect them indirectly through changes in vegetation cover. Increasing variability in environmental conditions could lead to more ITV, but responses might differ among species. Disentangling these drivers on ITV is necessary to accurately predict plant community responses to global change. We planted herb communities into forest soils with and without a recent history of agriculture. Soils were collected across temperate European regions, while the 15 selected herb species had different colonizing abilities and affinities to forest habitat. These mesocosms (384) were exposed to two-level full-factorial treatments of warming, nitrogen addition and illumination. We measured plant height and specific leaf area (SLA). For the majority of species, mean plant height increased as vegetation cover increased in response to light addition, warming and agricultural legacy. The coefficient of variation (CV) for height was larger in fast-colonizing species. Mean SLA for vernal species increased with warming, while light addition generally decreased mean SLA for shade-tolerant species. Interactions between treatments were not important predictors. Environmental change treatments influenced ITV, either via increasing vegetation cover or by affecting trait values directly. Species' ITV was individualistic, i.e. species responded to different single resource and condition manipulations that benefited their growth in the short term. These individual responses could be important for altered community organization after a prolonged period.


Subject(s)
Climate Change , Ecosystem , Forests , Europe , Nitrogen/metabolism , Plants/metabolism , Soil/chemistry
2.
Plant Biol (Stuttg) ; 22(3): 410-424, 2020 May.
Article in English | MEDLINE | ID: mdl-31840363

ABSTRACT

Functional traits respond to environmental drivers, hence evaluating trait-environment relationships across spatial environmental gradients can help to understand how multiple drivers influence plant communities. Global-change drivers such as changes in atmospheric nitrogen deposition occur worldwide, but affect community trait distributions at the local scale, where resources (e.g. light availability) and conditions (e.g. soil pH) also influence plant communities. We investigate how multiple environmental drivers affect community trait responses related to resource acquisition (plant height, specific leaf area (SLA), woodiness, and mycorrhizal status) and regeneration (seed mass, lateral spread) of European temperate deciduous forest understoreys. We sampled understorey communities and derived trait responses across spatial gradients of global-change drivers (temperature, precipitation, nitrogen deposition, and past land use), while integrating in-situ plot measurements on resources and conditions (soil type, Olsen phosphorus (P), Ellenberg soil moisture, light, litter mass, and litter quality). Among the global-change drivers, mean annual temperature strongly influenced traits related to resource acquisition. Higher temperatures were associated with taller understoreys producing leaves with lower SLA, and a higher proportional cover of woody and obligate mycorrhizal (OM) species. Communities in plots with higher Ellenberg soil moisture content had smaller seeds and lower proportional cover of woody and OM species. Finally, plots with thicker litter layers hosted taller understoreys with larger seeds and a higher proportional cover of OM species. Our findings suggest potential community shifts in temperate forest understoreys with global warming, and highlight the importance of local resources and conditions as well as global-change drivers for community trait variation.


Subject(s)
Ecosystem , Forests , Plants , Europe , Global Warming , Nitrogen/metabolism , Plant Leaves/physiology , Plants/metabolism , Soil/chemistry
4.
Semin Oncol ; 22(3 Suppl 6): 97-100, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7597439

ABSTRACT

Second-line treatment with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) may achieve remissions in patients suffering from ovarian cancer who have failed primary chemotherapy with cisplatin- or carboplatin-based regimens. Introduction of paclitaxel in combination with cisplatin into the first-line treatment strategy was therefore the next logical step in the development of chemotherapy against ovarian cancer. Data already have shown that this may result in better survival. Since carboplatin may replace cisplatin, the combination of paclitaxel with carboplatin seemed a further necessary step. We therefore embarked on a dose-finding study of paclitaxel and carboplatin. Fourteen patients with International Federal of Gynecology and Obstetrics stage III and IV ovarian cancer with a median age of 55.5 years entered this study of escalating doses of either carboplatin or paclitaxel. Doses of carboplatin could be escalated from 300 to 450 mg/m2 and paclitaxel could be escalated from 125 to 175 mg/m2 without dose-limiting myelosuppression. At the highest dose level reported here, only transient short-lived leukopenia was observed. Other toxicities consisted of nausea and vomiting, peripheral neurotoxicity, and arthralgia, all mild. In the first 14 patients, 10 of whom are evaluable, complete remissions were seen in two patients and partial remissions in six. This study will escalate the doses of paclitaxel and carboplatin further. This treatment is well tolerated and yields satisfactory antitumor results.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Ovarian Neoplasms/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carboplatin/administration & dosage , Drug Administration Schedule , Female , Humans , Middle Aged , Paclitaxel/administration & dosage , Remission Induction
5.
World J Surg ; 13(4): 478-83, 1989.
Article in English | MEDLINE | ID: mdl-2773504

ABSTRACT

The effect of surgery on inflammation was studied in male Wistar R/A rats using the carrageenin-induced edema model. Swelling of the paw was measured in standardized arbitrary units 2, 4, and 6 hr after a subcutaneous injection of carrageenin iota in the subplantar region of the right hind limb. It was significantly depressed in rats submitted to laparotomy (5.0 +/- 0.4, 8.0 +/- 1.0, 13.7 +/- 1.9) when compared with controls simply anesthetized with ether (6.2 +/- 0.5, 15.5 +/- 1.2, 23.7 +/- 0.6) (p less than 0.001 at 4 and 6 hr). This inhibition lasted for at least 24 hr and was also observed after amputation, although in these experiments, the difference between operated animals and controls was not significant. Alterations of the inflammatory cellular infiltrate were studied using polyurethane sponges soaked with carrageenin lambda implanted subcutaneously in control animals and rats undergoing laparotomy or amputation. The total number of cells recovered from these sponges 5 hr after implantation was smaller in operated rats (2.9 +/- 0.4 x 10(6) cells after laparotomy, 3.1 +/- 1.0 x 10(6) cells after amputation) when compared with controls (11.1 +/- 1.9 x 10(6) cells and 10.3 +/- 1.3 x 10(6) cells) (p less than 0.001 for laparotomy and p less than 0.005 for amputation). The inhibitory effect of operative trauma was not abolished by bilateral adrenalectomy performed 12 days before laparotomy. In rats, surgical trauma induces a depression of remote inflammatory reactions. This phenomenon is not related to increased corticosterone levels.


Subject(s)
Inflammation/metabolism , Surgical Procedures, Operative/adverse effects , Adrenal Glands/metabolism , Animals , Carrageenan , Edema/metabolism , Inflammation/etiology , Rats , Rats, Inbred Strains
7.
J Comput Assist Tomogr ; 9(3): 480-4, 1985.
Article in English | MEDLINE | ID: mdl-3989041

ABSTRACT

One hundred fifty-three patients with bronchogenic carcinoma were evaluated prospectively by CT and mediastinoscopy. Nodes larger than 5 mm were considered potentially metastatic. All results were correlated with surgical findings. Computed tomography is more sensitive (89%) in the detection of mediastinal metastases than mediastinoscopy (67%). Computed tomography has a poor predictive value (47%); however, a negative examination is highly accurate (89%). Within a group of 100 node sites, 72% of the nodes involved by tumor were larger than 1 cm in diameter. Squamous cell carcinoma and adenocarcinoma have the highest percentages of sensitivity by CT. The very low incidence of metastatic involvement in nodes under 5 mm allows one to forego mediastinoscopy in the presence of a negative CT.


Subject(s)
Carcinoma, Bronchogenic/pathology , Lung Neoplasms/pathology , Mediastinoscopy , Tomography, X-Ray Computed , Adenocarcinoma/pathology , Carcinoma, Squamous Cell/pathology , Humans , Lung/pathology , Lymph Nodes/pathology , Lymphatic Metastasis , Neoplasm Staging , Preoperative Care , Prospective Studies
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