Effects of high Zn and Pb concentrations on Phragmites australis (Cav.) Trin. Ex. Steudel: Photosynthetic performance and metal accumulation capacity under controlled conditions.

The response of Phragmites australis (Cav.) Trin. Ex. Steudel to zinc (Zn) and lead (Pb) was studied separately in two hydroponic tests, during a three weeks experiment. The effects on ecophysiology and biomass partitioning were evaluated during the metal treatments and at the recovery, and total metal content and accumulation capacity in different plant organs were assessed. Zn and Pb had different effects on the overall measured parameters, highlighting different mechanism of action. In particular, Zn concentration was higher in roots and, being a micronutrient, it was translocated into leaves, producing a reduction of assimilation rate, stomatal conductance (-71.9 and -81.3% respect to the control plant respectively), and a strong down regulation of photosystems functionality both at PSII and PSI level. Otherwise, Pb was accumulated mainly in the more lignified tissue such as rhizomes, with slightly effect on gas exchange. Chlorophyll a fluorescence highlighted that Pb inhibits the electron transfer process at the PSI donor side, without recovery after the removal of the metal stress. Despite these physiological limitations, P. australis showed a high capacity to accumulate both metals, and only slight reduction of biomass, being therefore a suitable species for phytoremediation interventions.

Preliminary shape analysis of the outline of the baropodometric foot: patterns of covariation, allometry, sex and age differences, and loading variations.

AIM: Baropodometrical digital techniques map the pressures exerted on the foot plant during both static and dynamic loadings. The study of the distribution of such pressures makes it possible to evaluate the postural and locomotory biomechanics together with its pathological variations. This paper is aimed at evaluating the integration between baropodometric analysis (pressure distribution) and geometrical models (shape of the footprints), investigating the pattern of variation associated with normal plantar morphology. METHODS: The sample includes 91 individuals (47 males, 44 females), ranging from 5 to 85 years of age (mean and standard deviation = 40 + or - 24).The first component of variation is largely associated with the breadth of the isthmus, along a continuous gradient of increasing/decreasing flattening of the foot plant. This character being dominant upon the whole set of morphological components even in a non-pathological sample, such multivariate computation may represent a good diagnostic tool to quantify its degree of expression in individual subject or group samples. RESULTS: Sexual differences are not significant, and allometric variations associated with increasing plantar surface or stature are not quantitatively relevant. There are some differences between adult and young individuals, associated in the latter with a widening of the medial and posterior areas. CONCLUSIONS: These results provide a geometrical framework of baropodometrical analysis, suggesting possible future applications in diagnosis and basic research.

Effect of parenteral antioxidants on adrenal pathobiology and leukocytes in hyperammonaemic toxaemia.

Infestation of sheep by L. cuprina larvae produces extensive skin wounds, severe dermatitis, hyperammonaemia and stress with adrenal necrosis and haemmorhage. In infested sheep, intramuscular (im) injections of Dl-Alpha tocopherol induced wool shedding and Desferrioxamine im prevented declines in white blood cells (WBC). In further trials, daily im injections of sodium ascorbate with Dl-alpha tocopherol, desferrioxamine and oral butylated-hydroxyanisole prevented adrenal damage and induced adrenocortical hypertrophy of the zona fasciculata. The treatment boosted the levels of mature and juvenile neutrophils, and blood glucose. Increases in toxic ammonia levels were correlated with increased toxic and band neutrophils, and globulin levels in treated sheep and toxic neutrophils in non-treated sheep. Decreases in serum zinc were correlated with declining lymphocytes and globulin levels. The results suggested that antioxidants protect and enhance adrenal activation in hyperammonaemic toxaemia. The changes in WBC, globulins and glucose were consistent with protected adrenocortical activation.

Effect of antioxidants on ammonia induced CNS-renal pathobiology in sheep.

The effect of antioxidants on ammonia induced CNS and renal pathobiology in 10 sheep infested by L. Cuprina larvae was investigated. The condition produces severe dermatitis, proliferation of macrophages and hyperammonaemia, and free radicals may therefore be involved in the pathogenesis. Five of the sheep (treated group) were given daily intramuscular (im) injections of 2 g sodium ascorbate, 5.9 g dl-alpha tocopherol (11 days) and 3 g desferrioxamine mesylate (6 days) with 70 mg oral butylated-hydroxyanisole (11 days). The treatment prevented rises in jugular ammonia, creatinine, urea, sodium and pH, and decreases in water intake, urine output and glucose. The findings showed that antioxidants prevented ammonia induced CNS and renal pathobiology and suggest that free radicals contribute to the pathogenesis of the condition.

Excretion of ammonia by Lucilia cuprina larvae suppresses immunity in sheep.

Attempts to immunise sheep against natural infestations by Lucilia cuprina larvae have not been effective. Yet it is known that the larvae excrete the immunosuppressant ammonium bicarbonate. The effect of larval ammonium and nonionic ammonia on immunopathobiology was evaluated in 12 infested sheep. The concentration of ammonium in veins draining infested sites was measured in another group of four sheep. Mean jugular unionized ammonia concentration increased 3.5 to 5.6 times above pre-infested control levels. Mean venous ammonium concentrations draining infested sites were 13 times higher than pre-infested jugular or carotid levels. Increases in jugular ammonia concentrations correlated with increased number of larvae, area of infestation, earlier death, neutropenia, eosinopenia, lymphocytopenia, large declines in serum globulins and zinc, and large rises in toxic neutrophils. The high concentrations of toxic unionized ammonia in blood directly permanently damaged neutrophils and lymphocytes and depressed serum globulin production. The results show that the ammonium from the excreta of larvae of L. cuprina may be highly immunosuppressive.

Effects of azadirachtin on Ctenocephalides felis in the dog and the cat.

Azadirachtin-containing neem seed extract is a powerful insect growth regulator, a feeding deterrent and repellent with low toxicity. Unfortunately, azadirachtin degrades rapidly in light, excessive heat or alkalinity. Evaluations of azadirachtin on ectoparasites on animals have been scarce. The purpose of this work was to describe the effects of normal and potentiated azadirachtin on Ctenocephalides felis in the dog or cat. Groups of kennelled greyhounds and domestic cats infested with C. felis were sprayed once with azadirachtin containing neem seed extract with or without diethyltoluamide (Deet) and/or citronella. Methanolic extracts with 200, 1000 or 2400 ppm azadirachtin reduced fleas in a dose-dependent manner. Compared with fleas counted on treated dogs just before treatment and untreated infested dogs, 1000-2400 ppm azadirachtin reduced fleas 93-53% for 19 days. However, combined with 500 ppm Deet and 33% w/v citronella, only 500 ppm azadirachtin reduced fleas 95-62% for 20 days. On cats inoculated with 50 fleas 2 days before treatment, the combination reduced fleas and eggs 100% to day 6 and 83-51% from day 7 to 9. On petri dishes, the combination achieved 100% egg mortality up to day 7 and 80% to day 14 and 48-52% to days 21-28. Deet, with or without neem seed extract or citronella, and citronella, with or without neem, did not reduce fleas significantly. The results show that azadirachtin reduced fleas in a dose-dependent manner in flea-contaminated environments. In cats, the combination killed most fleas within 24 h, providing effective flea control for 7 days. The results suggest that Deet with citronella potentiated the effect of azadirachtin on C. felis.

Food intake of sheep exposed to hot-humid, hot-dry, and cool-humid environments.

Water intake, food intake (wet and dry weight), rectal temperature, and food digestibility were determined in 6 sheep exposed to 4 weeks each of hot-humid, hot-dry, and cool-humid environments, alternated with 3 weeks each of cool-dry exposure. Compared with values determined during the cool-dry environments, wet-weight food intake decreased between 5% and 33% and between 3% and 9% during hot-humid and hot-dry exposures, respectively. During the week of cool-humid exposure, wet-weight food intake decreased by 11%. During hot-humid, hot-dry, and cool-humid environments, dry-weight food intake decreased between 5% and 17%. The effect of high ambient temperatures on wet-weight food intake was significant (P less than 0.01), whereas dry-weight food intake was not related to ambient temperature. During hot-humid exposure, water intake decreased 4% and the increased 7%. During hot-dry exposure, water intake increased between 37% and 45%. During the first 2 weeks of cool-humid environment, water intake decreased between 13% and 15%. From the 4th week of hot-humid exposure until the 3rd week of the following cool-dry period, food digestibility increased between 18% and 32%. During hot-dry exposure, food digestibility increased between 6% and 14%. The digestibility of food was significantly increased (P less than 0.005) when dry-weight food intake increased; therefore, decreased digestibility was related to water content of the feed. Increased ambient humidity was associated with decreased dry-weight food intake (P less than 0.05).

Effect of ambient temperature and humidity on urine output in sheep.

Urine output, respiratory rate, water intake, plasma and urine osmolalities, and PCV of 6 sheep exposed to 4 weeks of each of hot-humid, hot-dry, and cool-humid environments alternated with 3 weeks each of cool-dry control environments were determined. Compared with urine output during the control environment, urine output increased during hot-humid, hot-dry, and cool-humid exposure, but was 70% greater during the hot-humid environment than during hot-dry exposure. Water intake increased 37% to 45% during hot-dry exposure but decreased 35% during the first 2 weeks of cool-humid exposure. Urine osmolality decreased 38%, 22%, and 44% during hot-humid, hot-dry, and cool-humid exposure, respectively, whereas plasma osmolality values only increased 3% during hot-dry exposure. Respiratory rates increased on exposure to both hot environments, but decreased during cool-humid exposure. The PCV decreased 3% after 1 week of hot-humid exposure, 8% after 4 weeks of hot-dry exposure, and 5% after 4 weeks of cool-humid exposure. Urine output, and probably plasma volume, increased during these periods because evaporative heat loss was reduced due to the lack of adequate air convection and mobility. Heat loss through increased urine output was not significant (P less than 0.2). Enclosed sheep should be kept with short fleeces and should be maintained in conditions of low temperature and adequate convection if representative physiologic, biochemical, and pharmacologic assessments are desired.

Pharmacokinetics of cefotaxime in sheep.

Five healthy adult Merino ewes were each given 2 g of cefotaxime by the IV, IM, and subcutaneous (SC) routes. The serial plasma samples collected after each treatment were analyzed for cefotaxime by a new high-pressure liquid chromatographic method. Plasma concentration time profiles were characterized by a linear 2-compartment model after IV administration and the following mean values (+/- SD) were found: biological half-life, 23 +/- 8 minutes; apparent volume of distribution, 5.5 +/- 1.3 L; plasma clearance, 0.37 +/- 0.09 L/min; elimination rate constant, 0.066 +/- 0.014 minute-1; rate of diffusion into tissue, 0.013 +/- 0.013 minute-1; and out of tissue, 0.035 +/- 0.017 minute-1. Plasma cefotaxime concentrations in the ewes given the drug by the IV, IM, and SC routes were 113 +/- 32, 71 +/- 20, and 38 +/- 11 micrograms/ml, respectively, at 15 minutes; 2.31 +/- 0.82, 11.3 +/- 6.6, and 16.4 +/- 3.7 micrograms/ml at 120 minutes; and 1.05 +/- 1.22, 9.3 +/- 5.2, and 14.9 +/- 1.27 micrograms/ml at 150 minutes. After cefotaxime was given SC and IM, plasma values were higher for a longer time than they were after the drug was given IV, probably due to a slower release of drug from the former injection sites.

Pharmacokinetic evaluation of a slow-release cefotaxime suspension in the dog and in sheep.

Three Merino ewes were given cefotaxime IM, and 3 were given cefotaxime subcutaneously (50 mg/kg of body weight each); each dose was suspended in 6 ml of oil. Five dogs were also given an oily suspension of cefotaxime subcutaneously (SC) (50 mg/kg of body weight). The plasma concentrations (Cp) and pharmacokinetic data obtained after cefotaxime in the oily suspension was injected IM and SC were compared with data from the same animals after they were given an aqueous solution of cefotaxime by the same routes. Key pharmacokinetic values obtained after cefotaxime was administered IV to sheep and to dogs are discussed. Mean peak Cp (Cpeak) in sheep when given the oily suspension IM was approximately 53 micrograms/ml at 0.18 to 0.40 hour, and that value in sheep given the aqueous preparation was 62 micrograms/ml 0.08 to 0.18 hour. Mean Cpeak values after the oily suspension and the aqueous preparation were injected SC were 11.0 micrograms/ml (between 0.8 and 1 hour) and 51 micrograms/ml (between 0.25 and 1 hour), respectively. Bioavailabilities were approximately 70% after IM injection was done and 90% after SC injection was done. The beta-plasma half-lives were 0.7 hour after IM injection was done and 2.9 hours after SC injection was done. Mean Cpeak in dogs when given the oily suspension SC was 30 micrograms/ml at 1.0 hour, and when dogs were given the aqueous preparation SC, Cpeak was 27 micrograms/ml at 0.6 hour. Absorption was virtually complete after the oily suspension and aqueous preparations were given.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics of cefotaxime in the dog.

Each of five dogs was given cefotaxime at a dose rate of 50 mg/kg by intravenous, intramuscular and subcutaneous routes, in three separate treatments. Plasma concentration time profiles were characterised by a linear two-compartment model after the intravenous administration. After intravenous, intramuscular and subcutaneous injections the mean biological half-lives were 0.74, 0.83 and 1.71 hours, respectively. The apparent steady state volume of distribution was 0.48 litre/kg and body clearance after intravenous injection was approximately 0.63 litre/hour/kg. After intramuscular and subcutaneous injections peak plasma cefotaxime concentrations were 47 +/- 15 and 29.6 +/- 16 micrograms/ml at 0.5 and 0.8 hours, respectively. The average bioavailability of cefotaxime given by intramuscular injection was 86.5 per cent and for cefotaxime given subcutaneously it was approximately 100 per cent. After two hours, the cefotaxime plasma concentration remained higher after subcutaneous than after intramuscular administration.

Lucilia cuprina induced hyperammonaemia and alkalosis associated with pathology in sheep.

Gross and microscopical examinations were done in 12 sheep infested with Lucilia cuprina larvae. All the sheep became hyperammonaemic and alkalotic. Six sheep died and 6 survived, one being moribund before euthanasia. Necropsy revealed severe acute dermatitis and congestion of the liver, heart, kidney, spleen and lungs. Ecchymotic haemorrhages were present in the heart, kidneys and adrenal glands of severely infested sheep. Microscopical examination showed mild to severe vacuolation of the central nervous system in all sheep. In severely infested sheep, skin, lung, heart, kidney, and liver tissues were infiltrated by mononuclear cells, neutrophiles or lymphocytes. Fibrin thrombi were present in vessels. Elevated concentrations of lipid soluble ammonia in blood were positively correlated with tissue abnormality and early death.

The natural history of sensitizations to food and aeroallergens in atopic dermatitis: a 4-year follow-Up.

The natural history of atopic dermatitis (AD) is variable. Generally the dermatitis disappears during the first years of life, but it is often followed by the appearance of allergic respiratory diseases (ARDs). Our aim was to establish the risk factors for developing an ARD in children with AD. We followed up for 4 years 78 children (51 boys, 27 girls) with mild (26%), moderate (48%), and severe (26%) AD (clinical score proposed by Rajka and Langeland). In all the patients IgE serum levels were checked and skin prick tests (SPTs) were performed at the first examination. The SPTs were repeated in 68 children at the end of the study. The children with severe AD had significantly higher IgE serum levels than those with mild or moderate AD. SPTs at the first observation were positive in 47% of cases, mostly in patients with severe AD, with a prevalence of food allergens, particularly in younger patients. At the second observation, SPTs were positive in 65% of cases, including 100% of children with severe AD. Inhalants were the most common allergens. An ARD appeared in 38% of all patients: in 75% of those with severe AD and in 54% of those with a positive first SPT. Allergic screening should be carried out at an early age, especially in severe AD, since SPT positivity to food allergens, associated with severe clinical AD symptoms and a high IgE serum level, identifies those children ages 0-3 years at high risk of development of ARD.

Eruptive pseudoangiomatosis.

Eruptive pseudoangiomatosis (EPA) is a rare, benign, spontaneously regressing childhood exanthem. The term was recently coined by Prose et al.1 to describe a dermatosis characterized by the sudden onset of a few to several bright red angioma-like papules with a different histopathology from the true angiomas. We describe three patients with the typical lesions of EPA but with some peculiar features not previously described. We discuss the suspected viral aetiology of EPA, and hypothesize a multifactorial aetiopathogenesis.

Evoked potentials in the evaluation of patients with mitochondrial myopathy.

Multimodality evoked potentials and pattern electroretinograms (PERGs) were performed in seventeen patients with histologically defined mitochondrial myopathy (MM). Brainstem auditory evoked potentials showed abnormalities in 47% and somatosensory evoked potentials in 76%. Visual evoked potentials were outside the normal range in 71%; PERGs exhibited a decreased amplitude or delayed P50 in 78%. These findings may be considered as an expression of impairment of the central nervous system in MM, even if the specific mechanism, 'structural' or 'functional', needs further investigation.

Persistent milia, steatocystoma multiplex and eruptive vellus hair cysts: variable expression of multiple pilosebaceous cysts within an affected family.

BACKGROUND: Steatocystoma multiplex (SM) and eruptive vellus hair cysts (EVHC) are conditions characterized by numerous cutaneous cysts with a clinical resemblance, such as age of onset, location, appearance of the lesions and mode of inheritance, but with distinctive histologic features. Recently, some authors have proposed that the two conditions are variants of one entity originating in the pilosebaceous duct, while others suggest that SM and EVHC are two distinct entities, on the basis of the different expression of keratins. Milia are small round cysts, commonly involving the face. In 1994, Menni and Piccinno reported the first association, in a family, between persistent infantile milia in a 9-month-old girl and SM in the father. The authors hypothesized a relationship between these two conditions. OBJECTIVE: We describe a family in which the mother showed cystic lesions and milia and her 4-year-old son and her 18-month-old daughter presented persistent infantile milia. METHODS: In addition to the clinical and genetic documentation, a biopsy was performed in the son and two biopsies in the mother. RESULTS: The histologic examination of one of the son's milium-like papules showed in the superficial dermis a small cyst typical of a milium. In serial sections it was possible to see a connection with a vellus hair follicle by an epithelial pedicle. The histologic examination of one of the mother's papules on the forehead showed a large round cystic structure with histologic features of EVHC. Close to the cyst wall, serial sections showed flattened sebaceous gland lobules. The histologic findings of the second biopsy taken from the chest showed the typical features of a steatocystoma. CONCLUSIONS: The relationship between milia, SM and EVHC is discussed; the three disease should be considered as subtypes of multiple pilosebaceous cysts that may all present overlapping histologic features. The different level of the pilosebaceous duct where the cyst originates should explain the different clinical manifestations.

[P300 and Parkinson disease. The role of cognitive changes]. / P300 e morbo di Parkinson. Ruolo nelle alterazioni cognitive.

Cognitive disturbances are frequently encountered in advancing Parkinson's disease (PD). Typically there are visuo-spatial disorders, memory impairment and bradyphrenia, defined as 'subcortical dementia' to distinguish it from the dementia that occurs in Alzheimer's disease, where the most prominent dysfunctions are agnosia, apraxia and aphasia. An electrophysiological test to study cognitive processing is the P300 (or P3) of the Event Related Potentials; in particular the latency of the P3 seems to correlate with cognitive decline. Thirty patients affected with idiopathic PD were investigated using a classic auditory "oddball" paradigm (rare tone--"target"--3000 Hz, frequent tone--"non target"--1000 Hz; the patients were instructed to recognize and keep a mental count of the number of rare tones). Electrophysiological findings were compared with those obtained in twenty normal subjects, age and sex matched with the patient's group. The parameters of P300 were correlated with patient's age, duration of the disease, motor and cognitive impairment levels and L-Dopa therapy. The P300 was loss in 16.6% (5 p.) and delayed in 33.3% (10 p.). Significative correlations were found only with age and cognitive impairment scores, but not with other variables analyzed. These results suggest that P300 could be a useful test to identify demented patients among those with PD, despite different motor disabilities.

Pharmacokinetics of cefotaxime and probenecid in sheep with normal and reduced renal function.

The pharmacokinetics of cefotaxime and probenecid, given by intravenous injection, were determined in six Merino ewes which had been subjected to a 75% reduction in renal mass. These results were compared with results previously determined in sheep with normal renal function. In the sheep with reduced renal mass, the following significant changes in parameter values for cefotaxime were observed. The elimination rate constant (kel) decreased by 47%, the apparent volume of the central compartment (Vc) decreased by 59%, the steady state volume (Vss) decreased by 50%, and the total body clearance (ClB) decreased by 78%. The rate constant for distribution of drug into tissues (k12) increased 6.9 times, the rate constant for distribution out of tissues (k21) increased 3.7 times, and the area under the plasma concentration-time curve (AUC) increased by a factor of 4.9. The parameter values, determined in sheep with reduced renal mass, for probenecid plasma half-life, Vss and the rate constants k12, k21, and kel were not significantly different from the values obtained previously in sheep with normal renal mass. However, the rate constant for renal excretion of probenecid (ke), renal clearance (ClR), ClB and Vc decreased by 79, 90, 54 and 36%, respectively. The results indicate that reduced renal mass increased the plasma half-life for cefotaxime as well as increasing its diffusion into tissue. In the case of probenecid the overall distribution and elimination kinetics were not altered by reduced renal mass; however, the rate of urinary excretion of the drug was reduced.