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In Arabidopsis thaliana (L.) Heynh., the cytosolic, patatin-related phospholipase A enzymes comprise a family of ten genes designated AtPLAs thought to be involved in auxin and pathogen signalling [A. Holk et al. (2002) Plant Physiol 130:90-101]. One of these, AtPLA IIA, is investigated here by studying its transcriptional regulation through transgenic Arabidopsis plants containing the AtPLA IIA promoter (PIIA) fused to the beta-glucuronidase (GUS) gene. GUS activity appeared in leaves at 10-12 days and became increasingly stronger with age in all leaves. From the same age on, strong GUS activity was visible in the basal stipules of the rosette leaves. PIIA-dependent GUS activity was found in the older parts of the primary root (from 10 days on) and, later in development, in older parts of side roots, and the root cap. No GUS activity was detected in flower organs. PIIA-dependent GUS expression in 12-day-old plants was up-regulated after treatment by salicylic acid, Bion, wounding, 1-aminocyclopropane-1-carboxylic acid (ACC) and jasmonic acid. When transgenic PIIA:: uidA plants were grown devoid of iron, 9-day-old plants exhibited increased GUS activity in the leaves and, when devoid of phosphate, 11-day-old plants had increased GUS activity in the roots. In conclusion, this member of the patatin-related phospholipase A gene family showed properties of a defence and iron-stress and phosphate-stress gene, being transcriptionally up-regulated within hours or days.

Rapid activation of phospholipase A (PLA) by auxin or plant-pathogen interaction suggests a function in signal transduction for this enzyme, but the molecular identification of a cytosolic PLA carrying out this function remains open. We isolated four cDNA sequences from Arabidopsis (ecotype Columbia), AtPLA I, AtPLA IIA, AtPLA IVA, and AtPLA IVC, which are members of the patatin-related PLA gene family in plants and which are homologous to the animal Ca(2+)-independent PLA(2) gene family. Expression was measured by reverse transcriptase-polymerase chain reaction, and AtPLA I transcripts were found preferentially in shoots, AtPLA IIA and AtPLA IVA in roots, and AtPLA IVC in flowers. Transient expression of the four PLA-green fluorescent protein fusion proteins in tobacco (Nicotiana tabacum) leaves showed they were located in the cytosol and not in the vacuoles. Surprisingly, AtPLA::green fluorescent protein was also localized to chloroplasts. The enzymatic activity of the purified recombinant AtPLA IVA toward phosphatidylcholine was dependent on Ca(2+), saturated at 0.5 mM, and had a pH optimum of about 7.0. It had both PLA(1) and PLA(2) specificity. The enzyme showed in vitro highest sensitivity toward the PLA(2) inhibitors palmitoyltrifluoromethyl ketone (PACOCF(3), K(i) approximately 30 nM), arachidonyltrifluoromethyl ketone (AACOCF(3), K(i) approximately 25 microM), and tetrahydro-3-(1-naphtalenyl)-2H-pyran-2-one (K(i) approximately 200 nM) and was also sensitive to other previously used inhibitors 5,8,11,14-eicosatetraynoic acid (K(i) approximately 3 microM) and nordihydroguajaretic acid (K(i) approximately 15 microM). The influence of these PLA(2) inhibitors on elongation in etiolated Arabidopsis seedlings was tested, and tetrahydro-3-(1-naphtalenyl)-2H-pyran-2-one and 5,8,11,14-eicosatetraynoic acid inhibited hypocotyl elongation maximally at concentrations close to their K(i) in vitro.

Falls prove to be a significant problem in geriatrics. 5% of falls lead to fractures and 10% to soft tissue injuries. We examined retrospectively the rehabilitation course of 78 patients, who had been treated by us after falls leading to injury. Fractures of the neck of femur predominated with 57%, followed by other fractures of the lower limbs with 13%. The remainder of the falls with consequences of injury lead to fractures of other parts and soft tissue injuries. In 34% of the falls, the cause was estimated as predominantly intrinsic and in 11% as extrinsic. 19% of the falls were a mixture of extrinsic and intrinsic factors. In 36% of the cases the cause remained unknown. Before the fall occurred, 72% were independent, 26% needed help and 1 patients was in need of care. After finishing rehabilitation 54% were independent, 34% needed help and 11% were in need of care. 86% were able to return to their usual social surroundings. Rehabilitation after falls with consequences of injury goes beyond mere "orthopedic" treatment. To minimize the future risk of fall, a precise analysis of the cause of fall should be implemented. One should moreover try to optimize the environment to reduce the risk.

This study evaluates the available literature about the prognosis of patients with apallic syndrome and similar illnesses. Different therapeutic strategies are not relevant in this review. The variation of the reported material did not permit a statistical metaanalysis. However, many interesting points of view could be elaborated leading to positive assistance in everyday situations. The chance of survival and the long-term outcome of comatose patients decrease with an increase in the age of the patient, the length and the degree of the coma. Cerebral predamage worses the long-term prognosis. Traumatic head injuries have a better prognosis than nontraumatic. Children (under 18 years of age) have a better prognosis than adults. The course of the oculomotoric symptoms can be used as a prognostic criterion. The somatosensory evoked potentials in the early phase correlate with the survival-chance and the long-term prognosis. The initial speed of recovery correlates with the long term outcome. Children and adults with traumatic apallic syndrome may recover over a period of 12 months. For apallic patients with other etiologies this time limit is 3 months. Few cases of recovery have been described outside these time limits. The average survival limit of permanent apallic patients is between 3 and 5 years. Particular patients have survived decades.