Surgical management of bilateral, upper and lower eyelid entropion in 27 Shar Pei dogs, using the Stades forced granulation procedure of the upper eyelid only.

Aims: To evaluate the outcome of surgical management of entropion of the upper and lower eyelids in Shar Pei dogs which had previously undergone temporary palpebral tacking, using the Stades forced granulation procedure of the upper eyelid only.Methods: Medical records were retrospectively searched to identify Shar Pei dogs referred for bilateral entropion of both the lower and upper eyelids, and that were treated with the forced granulation procedure of the upper eyelid only. Dogs were included if they had previously undergone unsuccessful temporary palpebral tacking and had at least three follow-up examinations in the 30 days following surgery.Results: Twenty-seven Shar Pei dogs with a median age of 7.9 (min 4, max 24) months were included in the study. Before surgery, all dogs showed signs of severe ocular discomfort with bilateral keratitis and visual deficit due to blepharospasm, enophthalmos and protrusion of the third eyelid. In 13/54 eyes, keratitis was associated with a corneal ulcer. When re-examined 4 weeks after surgery, correction of the upper eyelid entropion and associated trichiasis resolved ocular signs in 50/54 eyes. Mild bilateral lower entropion remained in two dogs postoperatively, which underwent revision surgery with the Hotz-Celsus technique. There were no cases of long-term recurrence of entropion or ocular irritation in the 38 eyes (19 dogs) which were re-examined 1 year after surgery.Conclusion and clinical relevance: The forced granulation procedure performed on the upper eyelid only was effective for correction of entropion in the Shar Pei dogs included in this study. In our experience, it is preferable to operate on the upper eyelid alone, rather than attempting to correct upper and lower entropion during the same surgical operation. The dog can then be reassessed a few weeks later to determine whether the lower entropion is anatomical or secondary to the severe blepharospasm resulting from the painful ocular irritation.

Carpal tunnel syndrome in HIV-positive patients coinfected with HCV.

A wide range of rheumatic and peripheral nervous system disorders may develop in patients with HIV infection, leading to pain, sensory symptoms, and muscle weakness. Over the past three decades, the progress in management of HIV disease with anti-retroviral therapy (ART) has resulted in increased life expectancy for people living with HIV disease. With this new chronicity of the disease has a constellation of chronic musculoskeletal, orthopaedic and rheumatic manifestations has emerged, as potential complications of the disease itself and/or the results of ART treatment regimen and/or because of expected age-related symptoms/manifestations. The incidence of CTS in the general population is around 3.8% with clinical examination and, when electroneuromyography is used, it is 2.7%. In the HIV-positive population, the incidence is very close to that of the general population. The aim of this study was to evaluate the incidence of CTS and to identify factors influencing the development of CTS in HIV-infected patients attending our clinic. This syndrome has been associated with advanced HIV disease and the use of ART possibly due to an increased inflammatory state and the presence of concurrent HCV infection.

Functioning and Disability in Leprosy.

This study has been carried out to investigate the frequency of musculoskeletal symptoms in people affected by leprosy and correlate this to their functional capacity to perform daily living and working activities and to their degree of disability. This cross-sectional study was performed on 100 clients who answered a questionnaire on personal and clinical data, the Nordic Musculoskeletal (QNSO), and the shoulder, arm and hand dysfunction (DASH) questionnaires. The mean age was 53.63 years and there was a predominance of men (67%), low education (53%), and multibacillary disease (84%). Physical impairment affected 95% of respondents and 92% indicated pain and/or paresthesia in the arms that interfered in functional capacity.Respondents with musculoskeletal symptoms have more difficulty to perform daily living and working activities compared to those without musculoskeletal symptoms (p-value<0.05). The presence of physical disabilities was not associated with difficulties to perform daily living (p-value=0.29) and labor activities (p-value=0.87). The majority of patients experienced pain and/or paresthesia of the arms, and this was associated with difficulties to perform daily living and working activities. However, the presence of physical disability does not seem to cause major impediments or limitations to perform these activities.

Implantation of a novel insertable cardiac monitor: preliminary multicenter experience in Europe.

BACKGROUND: The LUX-Dx™ is a novel insertable cardiac monitor (ICM) introduced into the European market since October 2022. PURPOSE: The aim of this investigation was to provide a comprehensive description of the ICM implantation experience in Europe during its initial year of commercial use. METHODS: The system comprises an incision tool and a single-piece insertion tool pre-loaded with the small ICM. The implantation procedure involves incision, creation of a device pocket, insertion of the ICM, verification of sensing, and incision closure. Patients receive a mobile device with a preloaded App, connecting to their ICM and transmitting data to the management system. Data collected at European centers were analyzed at the time of implantation and before patient discharge. RESULTS: A total of 368 implantation procedures were conducted across 23 centers. Syncope (235, 64%) and cryptogenic stroke (34, 9%) were the most frequent indications for ICM. Most procedures (338, 92%) were performed in electrophysiology laboratories. All ICMs were successfully implanted in the left parasternal region, oriented at 45° in 323 (88%) patients. Repositioning was necessary after sensing verification in 9 (2%) patients. No procedural complications were reported, with a median time from skin incision to suture of 4 min (25th-75th percentiles 2-7). At implantation, the mean R-wave amplitude was 0.39 ± 0.30 mV and the P-wave visibility was 91 ± 20%. Sensing parameters remained stable until pre-discharge and were not influenced by patient characteristics or indications. Procedural times were fast, exhibited consistency across patient groups, and improved after an initial experience with the system. Operator Operator feedback on the system was positive. Patients reported very good ease of use of the App and low levels of discomfort after implantation. CONCLUSIONS: LUX-Dx™ implantation appears efficient and straightforward, with favorable post-implantation sensing values and associated with positive feedback from operators and patients.

Characterization of the profession/occupation of individuals affected by leprosy and the relationship with limitations in professional activities.

People who had leprosy stay away from work and have difficulty of employability and to perform their functions or retire early. This study aimed at determining whether there is a relationship between profession/occupation and limitations in activities. This was a cross-sectional study that used the SALSA scale (Screening of Activity Limitation and Safety Awareness) to assess limitations and to classify professions/occupations as low, medium or high risk. Of the 277 people surveyed, 50.2% were men, the mean age was 53.8 years (SD = 16.3), 62.7% had multibacillary, 59.7% had family incomes of 3 minimum wages or less, 58.5% had up to 6 years schooling and 57% did not have paid jobs. As for occupations, 45.8% were considered low, 39.7% medium and 12.3% high risk. Of thetotal, 49.1% had mild/moderate, 8.7% severe/very severe and 42.2% did not have any limitations. The relationship between limitations in activities and occupational risk indicated that people with severe limitations tend to have low risk occupations (p value < 0.05). The limitations associated with employability showed that most active individuals have no limitations (p value < 0.05). Hence, most people who had leprosy have low risk professions/occupations; the limitations favor a shift from high-risk activities and interfere with employability.

First Report of Stemphylium vesicarium as Causal Agent of Wilting and Root Rotting of Radish Sprouts in Italy.

A consistent contamination from a Stemphylium sp. was detected on radish (Raphanus sativus) seeds by a seed blotter test. Twenty-five percent of seed lots were contaminated. Stemphylium vesicarium (teleomorph Pleospora allii) was identified on the basis of morphological characters of conidia and conidiophores (4). Conidia were golden brown to dark drown, oblong to oval with one to four transverse and one to three longitudinal septa, constricted at one to three of the major transverse septa. Conidia dimensions ranged from 12 to 22 × 30 to 40 µm. Conidiophores were straight or occasionally one-branched with a swollen apex and one to four septate. Pseudothecia with asci and ascopores were observed on radish seeds. Asci were cylindrical to clavate with eight ascospores with up to six transverse septa and numerous longitudinal septa. Species identification was also confirmed after comparing the sequences of the internal transcribed spacer (ITS) region of rDNA and gpd (glyceraldehyde-3-phosphate dehydrogenase) (3) of four isolates with those of Stemphylium species already present in the NCBI database. Accessions Nos. AM 746020 to AM746023 and AM883174 to AM883177 were deposited for ITS and gpd, respectively. Artificial inoculations were carried out on radish seeds previously disinfected with 1% sodium hypochlorite for 10 min and then plated on S. vesicarium sporulating colonies grown on potato dextrose agar (PDA). The four sequenced isolates were tested for pathogenicity. Disinfected seeds were plated onto PDA only and used as a control. After 48 h of incubation, seeds were sown in sterilized soil in plastic plates. The emerging and the eventually dead plants were counted. Stem necrosis and root rotting developed on sprouts within the first week after sowing. On the surviving infected plantlets, wilting and death occurred on more than 70% of the plants within 4 weeks after sowing. Control plantlets obtained from disinfected seeds remained healthy. The fungus reisolated from wilted and dead plants was morphologically identical to the original isolates, thus confirming S. vesicarium as the causal agent. In Italy, this pathogen is common on asparagus (1), but it has also been reported on Allium spp., tomato, and pear. On European pear it is the causal agent of brown spot (2), a destructive disease in the Mediterranean area but also in the Netherlands and other continental European countries. On the basis of these results, seed contamination with S. vesicarium can represent a threat for the production of radish for sprout consumption. To our knowledge, this is the first report of S. vesicarium on radish plantlets in Italy. References: (1) F. Del Zan et al. L'informatore Agrario 11:95, 1989. (2) I. Llorente and E. Montesinos. Plant Dis. 90:1368, 2006. (3) B. M. Pryor and D. M. Bigelow. Mycologia 95:1141, 2003. (4) E. G. Simmons. Sydowia 38:284, 1985.

Endometrial carcinoma: intraoperative evaluation of myometrial invasion. A prospective study.

AIM: The authors investigated the diagnostic value of intraoperative assessment of myometrial invasion in endometrial cancer patients. Following hysterectomy, the uterus was sectioned and macroscopically examined in order to assess the depth of myoinvasion, which was classified as <50% and >50%. In patients with macroscopic depth of invasion>30% and <50%, a frozen section of this area was carried out. The results of intraoperative evaluation were compared with the results of postoperative pathological examination. The agreement between methods was developed as generalized Kappa type statistic. Sensitivity, specificity, positive and negative predictive values for intraoperative only macro and macro/micro evaluation were calculated. METHODS: Seventy eight consecutive patients (median age 64 years, range 43-92; median Body Mass Index [BMI] 30.5, range 21.9-46.7) who underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy (THBSO) were included in the study. Following intraoperative macroscopic evaluation, frozen section was carried out in 15 (19%) patients. The median time to obtain the results was 16 min for macroscopic evaluation, and 29 min for the macro/micro assessment. RESULTS: Macroscopic only assessment correctly identified depth of myoinvasion in 91% of patients, while, when the frozen section was carried out, myoinvasion was correctly identified in 95% of patients. For macroscopic only and macro-micro assessment sensitivity and specificity were 76% and 98%, 86% and 98%, respectively. CONCLUSION: These data suggest that the frozen section may improve, the diagnostic value of macroscopic only intraoperative assessment of myometrial invasion in selected patients.

The invasion of abandoned fields by a major alien tree filters understory plant traits in novel forest ecosystems.

The abandonment of agricultural use is a common driver of spontaneous reforestation by alien trees. The N-fixing black locust (Robinia pseudoacacia L.) is a major alien invader of old fields in Europe. Here we show that canopy dominance by this tree may filter the frequency distribution of plant functional traits in the understory of secondary woodlands. Higher soil C/N ratio and available P are associated with black locust stands, while higher soil phenols associate with native tree stands. These environmental effects result in differences in understory flowering periods, reproduction types and life forms. Our findings emphasize the effect of a major alien tree on functional plant trait composition in the early stages of spontaneous reforestation of abandoned lands, implying the development of a novel forest ecosystem on a large geographical scale.

Chemical and biological characterization of dissolved organic matter from silver fir and beech forest soils.

Despite a growing attention to the dissolved organic matter (DOM) in terrestrial ecosystems and evidence of the fact that vegetation affects the quality of both undissolved and dissolved organic matter in soil, the role of DOM as a biological indicator is still poorly understood. In this work, the fertility of 59 sites, divided into eight key alliances of the order Fagetalia sylvaticae Pawl., was studied considering chemical and biological parameters such as soil DOM, hormone-like activity, low-molecular-weight (LMW) aliphatic and phenolic acids, and floristic data. Both non-parametric tests and principal component analysis (PCA) revealed differences between silver fir and beech forests and within each type of forest. There were also differences between neutrophilous and acidophilous types. What's more, PCA reveals the dominance of the auxin (IAA)-like activity, and of some phenolic acids in distinguishing the acidophilous beeches (ACI) form the other types, whereas the gibberellin (GA)-like activity is more relevant in neutrophilous conditions such as thermophilous (THE) and mesophilous (MESO) beeches and montane (MO), high montane (HMA), high montane (HMC) silver fir forests. The GA-like activity is also related to the succinic, fumaric, malonic, and l-malic acids in the MO, HMA and HMC silver fir forests. Moreover, the role of LMW aliphatic acids in mobilizing the hormone-like activity, which improves forest growth, is stressed. The growth of seedlings of Picea abies was influenced by the phenolic acid content. At concentrations between 1 and 100 microM, phenylacetic and protocatechuic acids inhibited root growth to the same extent as indoleacetic acid, while p-hydroxybenzoic acid had a stimulating effect comparable to that of gibberellic acid. The aliphatic and phenolic acids appear to be related to plant strategies that influence soil fertility affecting plant growth through rhizodeposition. The role of LMW aliphatic and phenolic acids as molecular markers of ecosystem function is noted.

Atrial electroanatomic remodeling after circumferential radiofrequency pulmonary vein ablation: efficacy of an anatomic approach in a large cohort of patients with atrial fibrillation.

BACKGROUND: Circumferential radiofrequency ablation around pulmonary vein (PV) ostia has recently been described as a new anatomic approach for atrial fibrillation (AF). METHODS AND RESULTS: We treated 251 consecutive patients with paroxysmal (n=179) or permanent (n=72) AF. Circular PV lesions were deployed transseptally during sinus rhythm (n=124) or AF (n=127) using 3D electroanatomic guidance. Procedures lasted 148+/-26 minutes. Among 980 lesions surrounding individual PVs (n=956) or 2 ipsilateral veins with close openings or common ostium (n=24), 75% were defined as complete by a bipolar electrogram amplitude <0.1 mV inside the lesion and a delay >30 ms across the line. The amount of low-voltage encircled area was 3594+/-449 mm(2), which accounted for 23+/-9% of the total left atrial (LA) map surface. Major complications (cardiac tamponade) occurred in 2 patients (0.8%). No PV stenoses were detected by transesophageal echocardiography. After 10.4+/-4.5 months, 152 patients with paroxysmal AF (85%) and 49 with permanent AF (68%) were AF-free. Patients with and without AF recurrence did not differ in age, AF duration, prevalence of heart disease, or ejection fraction, but the LA diameter was significantly higher (P<0.001) in permanent AF patients with recurrence. The proportion of PVs with complete lesions was similar between patients with and without recurrence, but the latter had larger low-voltage encircled areas after radiofrequency (expressed as percent of LA surface area; P<0.001). CONCLUSIONS: Circumferential PV ablation is a safe and effective treatment for AF. Its success is likely due to both PV trigger isolation and electroanatomic remodeling of the area encompassing the PV ostia.

The ParaSight-F rapid dipstick antigen capture assay for monitoring parasite clearance after drug treatment of Plasmodium falciparum malaria.

Three methods for the detection of Plasmodium falciparum infection in peripheral blood were compared during antimalarial treatment and follow-up in 32 Burundian patients: dipstick antigen capture assay, standard (TBF) and prolonged thick blood film examination (PTBF) (3 x 5 min and 3 x 20 min examination respectively). Parasitaemia was determined daily by comparison with total white blood cell counts (determined by Coulter counter) until no parasite was detected on 2 consecutive days by PTBF. Cumulatively, 231 observations were made with each assay: 64 were negative and 167 positive by PTBF (59 had parasite counts < or = 100/microL). Compared to PTBF, the sensitivities of TBF and the dipstick assay were 1.0 for parasite counts > 100/microL and 0.458 and 0.966 respectively for counts < or = 100/microL. Overall, the dipstick assay was significantly more sensitive (0.988 vs. 0.808; P < 0.001) but less specific (P = 0.013) than TBF. The dipstick assay is of potential use for monitoring response to drug treatment and for detecting low parasitaemias.

Response of uncomplicated falciparum malaria to oral chloroquine and quinine in Burundi highlands.

The in vivo response of falciparum malaria to oral chloroquine and quinine was evaluated in two identical hospital-based, comparative open trials carried out 2 years apart in the same seasonal period at a hospital located in the highlands of Northern Burundi. Children aged 0-14 with uncomplicated falciparum malaria were administered either chloroquine, at 25 mg/kg over 3 days, or quinine, at 10 mg/kg per 8 hourly for 5 days (alternate allocation) and treatment response was evaluated by the WHO 7-day test. In the first study (1992/1993) 472 patients qualified for analyses (211 in the chloroquine and 261 in the quinine group), as compared to 249 subjects in the second study (1994/1995). In each study, the response to quinine was significantly higher than that to chloroquine (P = 0.004 and < 0.001, respectively). While the response to quinine showed insignificant changes over time (95.8 vs. 92.9%), chloroquine was found to be significantly less effective in the second study as compared to the first (77.8 vs. 63.1%; OR (95% CI) 2.04 (1.21-3.43)). Such decline in chloroquine efficacy was attributable to the age group < 5 years of age, where response to chloroquine decreased from 72.9% in 1992/93 to 56% in 1994/1995. Uncontrolled chloroquine use, which spread after the onset in late 1993 of the still ongoing ethnic fighting, appears to be the most likely reason for such a decrease in chloroquine efficacy. Chloroquine resistance has long been known to be present in the hyperendemic lowlands of Burundi, but no data have so far been reported on the response to antimalarials in the highlands of the country. These findings should be considered when deciding on drug policies for the treatment of falciparum malaria in Burundi.

Intravenous immunoglobulin versus corticosteroid in treatment of Graves' ophthalmopathy.

We compared the effectiveness of systemic corticosteroids with the use of high-dose intravenous immunoglobulin (IVIG) in the treatment of Graves' ophthalmopathy. This was performed as a prospective, nonrandomized study including a blinded ophthalmological and orbital computed tomographic (CT) evaluation. The two groups of patients were not significantly different in relation to sex composition, age distribution, duration of Graves' disease, and ophthalmopathy and previous hyperthyroidism. All patients were followed up by endocrinologic evaluation and blinded ophthalmological (before therapy = B, at the end of therapy = E, and 6 months after the end = 6M) and orbital CT (B and E) evaluations. Twenty-seven patients treated with IVIG were followed up after the end of treatment for an average of 21 months (range 12 to 48 months). Soft tissue involvement (NOSPECS) improved or disappeared in 32 of 35 (90%) patients treated with IVIG and in 25 of 27 (92.5%) patients treated with corticosteroids. Diplopia improved or disappeared in 22 of 29 (75%) patients treated with IVIG and in 16 of 20 (80%) patients treated with corticosteroids. The results observed by clinical evaluation were confirmed with orbital CT score in 30 IVIG patients and in the corticosteroid-treated patients; a significant reduction of extraocular muscle thickness was observed after treatment in both groups. Proptosis improved or disappeared in 20 of 31 (65%) patients treated with IVIG and in 15 of 24 (62%) patients treated with corticosteroids. Mean values of proptosis evaluated by Hertel's exophthalmometer showed a slight reduction both in IVIG as well as in corticosteroid-treated patients. It is interesting to observe that in 28 IVIG-treated patients in whom it was possible to evaluate soft tissue involvement, proptosis and diplopia in the period between the fifth and sixth month from the start of therapy, the most important part of the amelioration (if responders) was already obtained at that time. Responder patients were defined in relation to the decrease in the highest NOSPECS class or grade. Among IVIG-treated patients 26 of 34 (76%) responded; while in the corticosteroid group 18 of 27 (66%) responded to treatment. The prevalences of patients who responded to the treatments were not significantly different in the two groups (Chi-square). The initial values of the subjective eye score were similar in the two groups, and a significant reduction was observed in both. Major side effects requiring discontinuation of the corticosteroid therapy were observed in two patients with hemorrhagic gastritis and in one patient with manic-depressive psychosis. Among 15 patients submitted to the evaluation of bone mineral content before and after corti-costeroid therapy, 4 presented signs of osteoporosis and 3 a reduction of bone mineral content. Moderate and minor side effects were more frequently noted in steroid-treated patients than in the IVIG group. These data suggest that IVIG is safe and effective in reducing the eye changes in patients with Graves' ophthalmopathy.

Autonomic nervous system imbalance and left ventricular systolic dysfunction as potential candidates for arrhythmogenesis in Becker muscular dystrophy.

We evaluated the arrhythmic profile in a population of 20 Becker muscular dystrophy (BMD) patients searching for possible correlations between the severity of the arrhythmic events, the cardiac autonomic balance (assessed by heart rate variability analysis in the time domain) and the degree of left ventricular systolic impairment. A population of 14 male healthy individuals served as the control group. BMD subjects exhibited lower values of SDNN (P=0.013), SDANN index (P=0.008) and 24-h mean heart rate (P=0.002). The total number of premature ventricular beats (totPVB) and the number of PVB out of 1000 heartbeats (PVB/1000) appeared also higher in BMD subjects (P=0.05 and P=0.046, respectively). No difference was found in terms of 24-h mean QTc and 24-h longest QT among the two groups. TotPVB and PVB/1000 were inversely related to both the ejection fraction (r= -0.620, P=0.004 and r= -0.517, P=0.019) and to the shortening fraction (r= -0.568, P=0.009 and r= -0.469, P=0.037). Twenty-four-h mean QTc was also inversely related to both the ejection fraction (r= -0.520, P=0.019) and the fractional shortening (r= -0.491, P=0.028). These data suggest that in BMD there is cardiac autonomic imbalance characterized by sympathetic predominance and an increased susceptibility to ventricular arrhythmias, even in the absence of overt cardiomyopathy. Furthermore, the severity of the arrhythmic profile in BMD appears closely related to the degree of left ventricular systolic dysfunction.

Cardiac evaluation for simultaneous pancreas-kidney transplantation and incidence of cardiac perioperative complications: preliminary study.

Type I diabetes mellitus (IDDM) is associated with an increased cardiovascular risk, and eligibility protocols for simultaneous pancreas-kidney transplantation (SPKT) are consequently accurate for preoperative cardiovascular assessment. According to our algorithm, coronary angiography in SPKT candidates is indicated for patients not only experiencing previous cardiac events or symptoms, but also those with long-standing diabetes (more than 25 years) and/or age over 45 years. Furthermore, a basal transthoracic echocardiographic exam (TTE) is performed to assess cardiac volumes, left ventricular mass, systolic function, and kinesis. The aims of this study were to evaluate perioperative cardiac morbidity and mortality in 18 SPKT-eligible patients, divided into two groups on the basis of the presence/absence of angiographically evident coronary artery disease (CAD), as well as to assess the impact of left ventricular hypertrophy (LVH) on cardiac complications. Cardiac intraoperative morbidity and mortality and postoperative mortality and major morbidity were absent; minor cardiac morbidity consisted only of silent ischemic ECG alterations, without significant differences between groups, although the incidence seemed to be higher in the CAD-positive population. LVH detected preoperatively by TTE exam also failed to correlate with the incidence of such complications. Selection of SPKT candidates by coronary angiography may have positive effects on perioperative cardiac morbidity and mortality. A larger sample size is needed to give the study statistical power. Medium- and long-term follow-up studies are warranted to evaluate the effects of preoperative selection on survival rates.

Effect of actinomycete metabolites on ion absorption by rice seedlings.

Humic fractions of molecular weight above (HSp) and below (HEf) 3.5 Kds obtained from faeces of earthworms (Allolobophora rosea and A. caliginosa), were compared with the exhausted culture broth of Actinomycetes (EAB) isolated from the same source. Hormone-like activity and efficiency of nitrate uptake by rice seedlings were stimulated by EAB and HEf, while HSp showed only negligible activity. EAB showed a stimulatory action on plant growth (dry weight) and affected the K, Ca, Mg, Fe absorption during the first two weeks of plant growth.

Micelle-like conformation of humic substances as revealed by size exclusion chromatography.

To gain further insight into the macromolecular behaviour of humic substances we treated a humic material with simple organic compounds and followed the change in molecular size distribution. Monocarboxylic, dicarboxylic, and tricarboxylic acids shifted the humic absorbance from high to low molecular sizes in size exclusion chromatograms. Mineral acids, phenol, alcohols, were not able to produce the same shift and gave total absorbance at the column void volume as in the case of humic substances alone. Our results are evidence of the micellar behaviour of humic substances in solution and of the importance of hydrophobic bondings in holding humic molecules together. The organic acids enter in the interior of the humic micelle and alter its stereochemical hydrophobic arrangement. In alkaline conditions, the developed negative charges disrupt the apparent high molecular size configuration and disperse the humic material into small-size micelles. This macromolecular property, that we report for the first time, may be of great importance in understanding the biological activity and the overall environmental behaviour of humic substances.

Soil organic matter mobilization by root exudates.

In order to study the different soil organic matter mobilisation by agrarian (Zea mais: cultivars Paolo and Sandek) and forest (Picea abies Karst. and Pinus sylvestris L.) root exudates, three different soils (Dystric Spodic Cambisol--S1, Haplic Luvisol--S2 and Calcaric Cambisol--S3) have been considered. Treating the soils with water (control) or plant root exudates, soil organic matter extracts were obtained. The extracts were characterised by hormone-like activities and gas chromatographic/mass spectrometric (GC/MS) measurements. Water extract and plant root exudates exhibited no hormone-like activity, while the other soil-extracts were endowed with a different hormone-like behaviour. GC/MS data indicated that in the acid soils (S1) Sandek and Picea abies exudates showed a greater ability in extracting organic acid isomers (Cl4COOH, Cl5COOH and Cl7COOH), while in neutral soils (S3) all the exudates were active in separating organic acids. In intermediate conditions (S2), Picea abies and Pinus sylvestris exudates liberated C15COOH isomers, Paolo C11COOH isomers, while Sandek was not effective. The different role of plant root exudates in mobilising bio-molecules from the bulk of the soil is proposed.

Biological activity of soil organic matter mobilized by root exudates.

In order to study the biological activity of soil organic matter mobilized by agrarian (Zea mays: cultivars Mytos and Samantha) and forest (Picea abies Karst. and Pinus sylvestris L.) root exudates, two different soils, an Eutric Cambisol (EC) and a Rendzic Leptosol (RL), were considered. Soil organic matter extracts were obtained by treating the soils with water (control) or plant root exudates. The extracts were characterized by hormone-like activities and gas chromatographic/mass spectrometric (GC/MS) measurements. Their effects on the nitrogen metabolism in maize seedlings were evaluated. The nitrogen organification in the maize seedlings has been greatly stimulated by all the organic acid extracts from the agrarian soil, while the extracts from the forest soil had no influence upon the metabolism; this indicated a probable link between the plant and the environment. The different biological activities of the extracts are discussed.

Evidence of drug interaction between cyclosporin A and H2-receptor antagonists (cimetidine, ranitidine and famotidine) in Sprague-Dawley rats.

H2-receptor antagonists, such as cimetidine (C), ranitidine (R) and famotidine (F) seem to be effective in the prevention and treatment of stress ulcer in transplant recipients receiving cyclosporin A (CyA). The aim of this study was to detect the possible synergistic nephro- and hepato-toxicity of these drugs, assaying the serum creatinine (SC), ALT, AST levels, and the histological features of 45 young male Sprague-Dawley rats, divided into nine groups of five rats each. After 10 days of treatment the results showed: (i) serum CyA levels were increased in the group receiving daily CyA (5 mg/kg) + R(5 mg/kg) (2430 +/- 403 ng/ml; p less than 0.05 vs. controls) and in the group receiving daily CyA (5 mg/kg) +/- C (10 mg/kg) (2440 +/- 265 ng/ml; p less than 0.01 vs. controls); (ii) ALT and AST levels were increased in this latter group (ALT 223 +/- 133 UL, AST 114.67 +/- 39 UL; p less than 0.01 vs. controls); (iii) SC levels were normal; and (iv) steatosis of the liver was observed in these two groups. These findings suggest that C and R, but not F, may inhibit the hepatic cytochromes P-450 which are involved in the oxidative metabolism of the drugs. Furthermore, the high serum CyA levels seem to play a major role in the appearance of biochemical and histological damage to the liver.