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E Pacini

Publications and source records attributed to E Pacini.

8 recordsLinked to original sources
PubMed2006

Pollen carbohydrates and water content during development, presentation, and dispersal: a short review.

Pollen accumulates starch reserves during development and the final stage of ripening. Before the anther opens, starch is totally or partially converted to pectins, glucose, fructose, sucrose, and to some unknown polysaccharides. Pollen is exposed to dispersing agents in an arrested developmental state which differs according to pollen water content. Pollen is classified as partially dehydrated or partially hydrated. The final water content may be reached before or after anther opening. Especially during exposure and dispersal, partially dehydrated pollen may interconvert soluble and insoluble reserves, modifying internal turgor pressure and hindering water loss or gain. Partially hydrated pollen is commonly devoid of mechanisms to conserve viability in time but has the advantage of quickly emitting pollen tubes on reaching the stigma.

Carbohydrates↗
PubMed2001

Pollen hydration status at dispersal: cytophysiological features and strategies.

The aim of this paper is to draw attention to partially hydrated pollen, namely, pollen grains having a high water content (> 30%); this type of pollen is more frequent than previously thought. Various cyto-physiological strategies are used to retain water during exposure and dispersal such as cytoplasm carbohydrates; in the absence of such strategies, fast pollination must be ensured, because uncontrolled loss of water leads to pollen death. On the other hand, a state of partial hydration allows a fast tube emission (even within 3-5 min). Several methods for determining the hydration status of pollen at anthesis are proposed.

Carbohydrates↗
PubMed1979

[Pulmonary damage in the rabbit caused by porcine pancreatic elastase and leukocyte lysate: unusual microscopic aspects].

Intratracheal injection of rabbit whole leukocyte homogenate induced emphysema-like lesions in rabbits. The lesions were produced only by preparations having elastinolytic activity. The pathological aspects appeared similar to those induced by the administration of porcine pancreatic elastase. The pulmonary changes, resembling several of the anatomic appearances of panacinar human emphysema, may be a suitable experimental model for studying histogenesis of panacinar human emphysema. Numerous abnormal fenestrations were present in air spaces walls and were a constant feature in opposition to that has been reported in elastase-treated hamsters. For the presence of a prominent dilatation of the periarterial lymphatic network, this experimental model might be used also for studying the ultrastructural features of pulmonary lymphatic vessels.

Animals↗