Datathons: fostering equitability in data reuse in ecology

Approaches to rapidly collecting global biodiversity data are increasingly important, but biodiversity blind spots persist. We organized a three-day Datathon event to improve the openness of local biodiversity data and facilitate data reuse by local researchers. The first Datathon, organized among microbial ecologists in Uruguay and Argentina assembled the largest microbiome dataset in the region to date and formed collaborative consortia for microbiome data synthesis.

Abundance and phylogenetic distribution of eight key enzymes of the phosphorus biogeochemical cycle in grassland soils

Grassland biomes provide valuable ecosystem services, including nutrient cycling. Organic phosphorus (Po) represents more than half of the total P in soils. Soil microorganisms release organic P through enzymatic processes, with alkaline phosphatases, acid phosphatases and phytases being the key P enzymes involved in the cycling of organic P. This study analysed 74 soil metagenomes from 17 different grassland biomes worldwide to evaluate the distribution and abundance of eight key P enzymes (PhoD, PhoX, PhoA, Nsap-A, Nsap-B, Nsap-C, BPP and CPhy) and their relationship with environmental factors. Our analyses showed that alkaline phosphatase phoD was the dataset's most abundant P-enzyme encoding genes, with a wide phylogenetic distribution. Followed by the acid phosphatases Nsap-A and Nsap-C showed similar abundance but a different distribution in their respective phylogenetic trees. Multivariate analyses revealed that pH, Tmax , SOC and soil moisture were associated with the abundance and diversity of all genes studied. PhoD and phoX genes strongly correlated with SOC and clay, and the phoX gene was more common in soils with low to medium SOC and neutral pH. In particular, P-enzyme genes tended to respond in a positively correlated manner among them, suggesting a complex relationship of abundance and diversity among them.

Predicting the clinical trajectory of feeding and swallowing abilities in CHARGE syndrome

To date, the feeding and oral-motor abilities of patients with CHARGE syndrome (CS) have not been longitudinally assessed. This study aims to investigate the level of these abilities at different ages and evaluate how they evolve during growth. We retrospectively analysed oral-motor features of 16 patients with molecularly confirmed CS (age range 4-21 years old; mean 11 years; SD 6 years; median 10 years). Nearly 100% of CS new-borns had weak sucking at birth, and half of them demonstrated poor coordination between breathing and swallowing. Over time, the percentages of children with tube feeding dependence (60% at birth) faced a slow but steady decrease (from 33% at 6 months, 25% at 12 months, to 13% at school age) in tandem with the decreasing risk of aspiration. The ability of eating foods requiring chewing was achieved at school age, after the acquisition of an adequate oral sensory processing. A mature chewing pattern with a variety of food textures was not achieved by more than half of patients, including those requiring artificial enteral nutrition. Most patients started prolonged oral-motor treatments with speech language therapists in early childhood.

CONCLUSIONS

Although feeding and swallowing disorders are constant features in CS patients, a slow and gradual development of feeding abilities occurs in most cases. Rehabilitation plays a key role in overcoming structural and functional difficulties and attaining appropriate eating skills.

WHAT IS KNOWN

• Feeding problems and swallowing dysfunction have been noted in CHARGE syndrome. • The involvement of multiple factors, including structural problems in the mouth, throat, or esophagus, and neurological impairment, make feeding a complicated task in CHARGE individuals.

WHAT IS NEW

• Dysphagia gradually improves in most CHARGE children over time, though with a wide interindividual variability. • The percentages of children with tube feeding dependence decrease over time from 60% at birth to 33% at 6 months and 13% at school age.

Drooling outcome measures in paediatric disability: a systematic review

Drooling, or sialorrhea, is a common condition in patients with cerebral palsy, rare diseases, and neurodevelopmental disorders. The goal of this review was to identify the different properties of sialorrhea outcome measures in children. Four databases were analysed in search of sialorrhea measurement tools, and the review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement. The COnsensus-based Standards for the selection of health status Measurement INstruments (COSMIN) checklist was used for quality appraisal of the outcome measures. The initial search yielded 891 articles, 430 of which were duplicates. Thus, 461 full-text articles were evaluated. Among these, 21 met the inclusion criteria, reporting 19 different outcome measures that encompassed both quantitative measures and parent/proxy questionnaires.   Conclusions: Among the outcome measures found through this review, the 5-min Drooling Quotient can objectively discriminate sialorrhea frequency in patients with developmental disabilities. The Drooling Impact Scale can be used to evaluate changes after treatment. The modified drooling questionnaire can measure sialorrhea severity and its social acceptability. To date, the tests proposed in this review are the only tools displaying adequate measurement properties. The acquisition of new data about reliability, validity, and responsiveness of these tests will confirm our findings. What is Known: • Although sialorrhea is a recognized problem in children with disabilities, especially those with cerebral palsy (CP), there is a lack of confidence among physicians in measuring sialorrhea. What is New: • Few sialorrhea measures are available for clinicians that may guide decision-making and at the same time have strong evidence to provide confidence in the results. • A combination of both quantitative measures and parent/proxy questionnaires might provide an adequate measurement of sialorrhea in children.

Reduced tillage, cover crops and organic amendments affect soil microbiota and improve soil health in Uruguayan vegetable farming systems

Conventional tillage and mineral fertilization (CTMF) jeopardize soil health in conventional vegetable production systems. Using a field experiment established in Uruguay in 2012, we aimed to compare the soil restoration potential of organic fertilization (compost and poultry manure) combined with conventional tillage and cover crop incorporated into the soil (CTOF) or with reduced tillage and the use of cover crop as mulch (RTOF). In 2017, table beet was cultivated under CTMF, CTOF and RTOF, and yields, soil aggregate composition and nutrients, as well as soil and table beet rhizosphere microbiota (here: bacteria and archaea) were evaluated. Microbiota was studied by high-throughput sequencing of 16S rRNA gene fragments amplified from total community DNA. RTOF exhibited higher soil aggregation, soil organic C, nutrient availability and microbial alpha-diversity than CTMF, and became more similar to an adjacent natural undisturbed site. The soil microbiota was strongly shaped by the fertilization source which was conveyed to the rhizosphere and resulted in differentially abundant taxa. However, 229 amplicon sequencing variants were found to form the core table beet rhizosphere microbiota shared among managements. In conclusion, our study shows that after only 5 years of implementation, RTOF improves soil health under intensive vegetable farming systems.

Two case reports of fetal alcohol syndrome: broadening into the spectrum of cardiac disease to personalize and to improve clinical assessment

BACKGROUND

Fetal alcohol spectrum disorder (FASD) refers to a broad spectrum of disabilities, in infants and children, resulting from moderate to excessive prenatal alcohol exposure. Significant associations with alcohol exposure were already reported with congenital structural heart defects: i.e. ventricular septal defects, atrial septal defects, conotruncal defects.

CASES PRESENTATION

We describe two cases of children with FASD, both admitted to the Center for Rare Diseases and Birth Defects of Policlinico Universitario Agostino Gemelli, in whom asymptomatic cardiac rhythm alterations were detected in absence of structural cardiovascular system anomalies or cardiac channelopathies.

CONCLUSIONS

No other reports about cardiac rhythm anomalies in individuals affected by FASD are actually available from the literature. We would like to make an alert for clinician, given the possibility of finding anomalies of heart conduction and rhythm in children affected by FASD even without structural congenital heart disease.

It Is Feasible to Produce Olive Oil in Temperate Humid Climate Regions

Worldwide olive industry has expanded into new climatic regions outside the Mediterranean basin due to an increase in extra virgin olive oil demand posing new challenges. This is the case of Uruguay, South America, where the olive crop area reached 10,000 hectares in the last 15 years and is intended to the production of EVOO. Uruguay has a temperate humid climate with mean precipitations above 1,100 mm per year but unequally distributed, mild winters, and warm summers, with mean annual temperatures of 17.7°C. Different agroecological conditions require local knowledge to achieve good productivity whereby the objective of this work was to show the feasibility and potential of olive oil production under our climatic conditions. For this the agronomic performance of Arbequina, Barnea, Frantoio, Leccino, Manzanilla de Sevilla, and Picual cultivars was evaluated along 10 years of full production. Phenology behavior, vegetative growth rate, productive efficiency, alternate bearing, and oil yield were determined. Sprouting and flowering processes occur in a wide window within the annual cycle between the months of August to November with great interannual variation. More than 8 t/ha fruit yield and 40% oil yields in dry weight basis were obtained in promising cultivars. However, alternate bearing arose as the main production limiting factor, with ABI values greater than 0.60 for most cultivars. We conclude that olive oil production in humid climate regions is feasible and the most promising cultivars based on productive efficiency are Arbequina and Picual.

Characterization of maize chitinase-A, a tough allergenic molecule

Food allergies are recognized as an increasing health concern. Proteins commonly identified as food allergens tend to have one of about 30 different biochemical activities. This leads to the assumption that food allergens must have specific structural features which causes their allergenicity. But these structural features are not completely understood. Uncovering the structural basis of allergenicity would allow improved diagnosis and therapy of allergies and would provide insights for safer food production. The availability of recombinant food allergens can accelerate their structural analysis and benefit specific studies in allergology. Plant chitinases are an example of food allergenic proteins for which structural analysis of allergenicity has only partially been reported. The recombinant maize chitinase, rChiA, was purified from Pichia pastoris extracellular medium by differential precipitation and cation exchange chromatography. Enzyme activity was evaluated by halo-assays and microcalorimetric procedures. rChiA modeling was performed by a two-step procedure, using the Swiss-Model server and Modeller software. Allergenicity of rChiA was verified by immunoblot assays with sera from allergic subjects. rChiA is active in the hydrolysis of glycol chitin and tetra-N-acetylchitotetraose and maintains its activity at high temperatures (70°C) and low pH (pH 3). The molecule is also reactive with IgE from sera of maize-allergic subjects. rChiA is a valuable molecule for further studies on structure-allergenicity relationships and as a tool for diagnosing allergies.

Transcriptomic analysis of nickel exposure in Sphingobium sp. ba1 cells using RNA-seq

Nickel acts as cofactor for a number of enzymes of many bacteria species. Its homeostasis is ensured by proteins working as ion efflux or accumulation systems. These mechanisms are also generally adopted to counteract life-threatening high extra-cellular Ni²⁺ concentrations. Little is known regarding nickel tolerance in the genus Sphingobium. We studied the response of the novel Sphingobium sp. ba1 strain, able to adapt to high Ni²⁺ concentrations. Differential gene expression in cells cultured in 10 mM Ni²⁺, investigated by RNA-seq analysis, identified 118 differentially expressed genes. Among the 90 up-regulated genes, a cluster including genes coding for nickel and other metal ion efflux systems (similar to either cnrCBA, nccCBA or cznABC) and for a NreB-like permease was found. Comparative analyses among thirty genomes of Sphingobium species show that this cluster is conserved only in two cases, while in the other genomes it is partially present or even absent. The differential expression of genes encoding proteins which could also work as Ni²⁺-accumulators (HupE/UreJ-like protein, NreA and components of TonB-associated transport and copper-homeostasis systems) was also detected. The identification of Sphingobium sp. ba1 strain adaptive mechanisms to nickel ions, can foster its possible use for biodegradation of poly-aromatic compounds in metal-rich environments.

Activity of Naturally Derived Antimicrobial Peptides against Filamentous Fungi Relevant for Agriculture

<p>The search for environmentally biocompatible and cost-effective methods to control filamentous fungi in agriculture is becoming increasingly urgent. <em>In vitro</em> antimicrobial activity of three synthetic peptides was investigated against some filamentous fungi with agricultural relevance. The peptides were an analog of Temporin called Temporizina, a fragment from Pleurocidin termed Plc-2, and a peptide identified from sesame seeds named Pses3. Antimicrobial activity of these peptides towards filamentous fungi has not been previously reported. Seven plant pathogenic or mycotoxigenic fungal species, isolated from plant tissues were assayed: <em>Alternaria</em> <em>solani</em>, <em>Colletotrichum</em> <em>gloesporioides</em>, <em>Fulvia </em><em>fulvum</em>, <em>Fusarium oxisporum</em>, <em>Aspergillus niger</em>, <em>A. ochraceus</em> and <em>Penicillium digitatum</em>. Values of Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) were determined and compared with the commercially available fungicide Captan as a positive control. The peptides showing greatest inhibition were Pses3 and Plc-2 and <em>C. gloesporioides </em>was the most sensitive of the evaluated fungi. The MICvalues for Plc-2 and Pses3 peptides ranged from 0.64 µM to 10.25 µM. These values were much lower than those observed for Captan, suggesting the potential of these peptides as fungicides. In particular, Pses3 is a novel peptide derived from sesame seeds not reported in databases.</p>

Dystonia in Costello syndrome

BACKGROUND

Costello Syndrome is a rare multiple congenital anomaly disorder caused by de novo heterozygous mutations in the v-Ha-ras Harvey rat sarcoma viral oncogene homolog (HRAS) gene. Recent studies seem to support apparent autosomal dominant inheritance and somatic mosaicism and an association with advanced parental age. Abnormal hand posture has been reported as a typical feature of Costello Syndrome but the pathophysiology of this is unclear.

METHODS

We evaluated and described posture and movement in six consecutive subjects with genetically proven Costello Syndrome, in order to better characterize the phenomenology of the associated postural abnormalities and any related motor abnormalities. We also evaluated motor cortex plasticity by applying Paired Associative Stimulation.

RESULTS

All the patients presented the typical postural abnormalities reported in Costello Syndrome, in particular the ulnar deviation of fingers. The latter was reducible and not fixed. In addition, patients exhibited more explicit dystonic features of the face, limbs and trunk and altered sensorimotor plasticity consistent with generalized dystonia.

CONCLUSIONS

These findings suggest that dystonia may underlie the abnormal postures described in Costello Syndrome patients.

Enhanced human brain associative plasticity in Costello syndrome

Costello syndrome (CS) is a rare multiple congenital anomaly disorder which is caused by germline mutations in the v-Ha-ras Harvey rat sarcoma viral oncogene homologue (HRAS) proto-oncogene. Experimental data suggest perturbing effects of the mutated protein on the functional and structural organization of networks of cerebral cortex and on the activity-dependent strengthening of synaptic transmission known as long term potentiation (LTP). In five patients with molecularly proven diagnosis of CS and in a group of 13 age-matched control subjects we investigated activity-dependent synaptic plasticity. To this end, we used a paired associative stimulation (PAS) protocol, in which left ulnar nerve stimuli were followed by transcranial magnetic stimulation (TMS) pulses to right cortical hand area, and recorded motor evoked potentials (MEPs) by single pulse TMS from left first dorsal interosseus (FDI) muscle before and after PAS. In 4 out of 5 CS patients and in a subgroup of nine control subjects we also evaluated the time course and the topographical specificity of PAS after-effects. In these two subgroups, MEPs were measured before, immediately after and 30 min after PAS in the left FDI and left abductor pollicis brevis (APB). While the PAS protocol led to a 65% increase of the FDI MEP amplitude in controls, the LTP-like phenomenon was significantly more pronounced in CS patients, with motor responses increased by 230%. In addition, CS patients showed a similar MEP increase in both muscles while control subjects showed a slight increase in APB and only immediately after PAS. We hypothesize that the extremely enhanced PAS after-effects could be due to the influence of HRAS activity on the susceptibility of synapses to undergo LTP.

Wolf-Hirschhorn syndrome with improvement of renal function

Wolf-Hirschhorn syndrome (WHS) is a chromosomal disorder characterized by partial deletion of the short arm of chromosome 4. We describe a girl with a de novo unbalanced traslocation t(4;7)(p16.2;p22), associated with a mild version of a classical WHS phenotype. She did not present major urinary tract abnormalities but had parenchymal hyperechogenicity at renal ultrasound at the birth with normal renal scintigraphy. She had also a reduction of GFR with elevated levels of blood urea nitrogen and serum potassium until the age of 6 months. We followed the patient with periodic clinical examination and laboratory and radiological investigations and observed at the age of 5 years a normal renal ultrasound without parenchymal hyperechogenicity.

Visual function in Noonan and LEOPARD syndrome

The aim of the study was to assess various aspects of visual and visuoperceptual function in patients with Noonan syndrome (NS) or LEOPARD syndrome (LS) with mutations affecting the PTPN11, SOS1 and RAF1 genes. Twenty-four patients were assessed with a battery of tests assessing visual function including ophthalmological and orthoptic evaluation and age appropriate behavioural visual tests, including measures of crowding acuity (Cambridge crowding cards), and stereopsis (TNO test). Twenty-one subjects were also assessed with the visuo-motor integration (VMI) test. Twenty of the 24 patients (83%) had abnormalities of visual function on at least one of the tests used to assess visual function or on ophthalmological examination, and 7 of 21 (33%) also had abnormalities on VMI. Ocular movements and stereopsis were most frequently abnormal (50% and 79%, respectively). Our results suggest that visual and visuoperceptual abilities are commonly impaired in patients with Noonan and LEOPARD syndrome and they are probably related to a multifactorial etiology.

Computerized detection of clustered microcalcifications: a modular approach with non-linear filters

The ideal computerized mammogram processing system still needs to be developed. In order to achieve maximum flexibility we suggest a modular scheme, dividing the processing sequence into functionally autonomous modules. This paper provides a general scheme for detection and/or automated recognition of microcalcifications. Some modules that perform ROI selection are introduced, using special non-linear filters designed for microcalcification detection. A first type of filter selects pixels with specific statistical local features, as compared to the local mean. Among these, only pixels satisfying particular constraints on the local standard deviation are kept. Another type of filter then checks the local mean values of gradient components, so that sharp variations, unrelated to small close objects, can be eliminated. The scheme thus applies different non-linear filters in combination, making precise identification of clustered microcalcifications possible. This modular approach seems greatly to simplify system maintenance and consistency, as well as affording a comparison of different processing techniques and parameters.

Neurite extension occurs in the absence of regulated exocytosis in PC12 subclones

We have investigated the process leading to differentiation of PC12 cells. This process is known to include extension of neurites and changes in the expression of subsets of proteins involved in cytoskeletal rearrangements or in neurosecretion. To this aim, we have studied a PC12 clone (trk-PC12) stably transfected with the nerve growth factor receptor TrkA. These cells are able to undergo both spontaneous and neurotrophin-induced morphological differentiation. However, both undifferentiated and nerve growth factor-differentiated trk-PC12 cells appear to be completely defective in the expression of proteins of the secretory apparatus, including proteins of synaptic vesicles and large dense-core granules, neurotransmitter transporters, and neurotransmitter-synthesizing enzymes. These results indicate that neurite extension can occur independently of the presence of the neurosecretory machinery, including the proteins that constitute the fusion machine, suggesting the existence of differential activation pathways for the two processes during neuronal differentiation. These findings have been confirmed in independent clones obtained from PC12-27, a previously characterized PC12 variant clone globally incompetent for regulated secretion. In contrast, the integrity of the Rab cycle appears to be necessary for neurite extension, because antisense oligonucleotides against the neurospecific isoform of Rab-guanosine diphosphate-dissociation inhibitor significantly interfere with process formation.

Molecular mechanisms of neurite extension

The extension of neurites is a major task of developing neurons, requiring a significant metabolic effort to sustain the increase in molecular synthesis necessary for plasma membrane expansion. In addition, neurite extension involves changes in the subsets of expressed proteins and reorganization of the cytomatrix. These phenomena are driven by environmental cues which activate signal transduction processes as well as by the intrinsic genetic program of the cell. The present review summarizes some of the most recent progress made in the elucidation of the molecular mechanisms underlying these processes.

Downregulation of MAP kinase activity signalled by HIV-1-gp120 coat protein in granular neurons and glial cells from rat cerebellum

We have studied the effect of gp120 coat protein from HIV-1 on tyrosine phosphorylation processes in primary cultures of granular neurons or glial cells from the cerebellum of neonatal rats. The extracellular application of recombinant gp120 (200 pM) was able to reduce the phosphotyrosine content and the immunoreactivity for active form-specific antibodies of MAP kinase. Whereas in neurons MAP kinase appeared to be the only protein whose phosphotyrosine content was decreased, in glial cultures the inhibitory effect of gp120 on tyrosine phosphorylation processes appeared to be more widespread. In neuronal cultures, the effect of the viral protein was prevented by the concomitant treatment with depolarizing agents.

Tat protein from HIV-1 activates MAP kinase in granular neurons and glial cells from rat cerebellum

We have investigated the effect of extracellularly applied Tat protein of the human immunodeficiency virus type 1 (HIV-1) on tyrosine phosphorylation processes, which represent a major signal transduction pathway of cells of the central nervous system. Primary cultures of rat cerebellar astrocytes or granule cells were incubated with synthetic Tat (10 ng/ml) for various periods of time and analyzed for their phosphotyrosine content by Western blotting. In both types of cultures Tat was able to induce the phosphorylation of mitogen-activated protein kinase (MAP kinase) on tyrosine residues, although with different kinetics and isoform specificity. In addition, in neuronal cells, but not in astrocytes, Tat increased the phosphotyrosine content of Shc, a protein involved in signal transduction downstream of receptor tyrosine kinase activation. This study shows that Tat applied extracellularly is able to induce the generation of intracellular signals in neuronal as well as glial cells.

Transudative vs exudative pleural effusions: differentiation using Gd-DTPA-enhanced MRI

The aim of this study was to investigate the capability of Gd-DTPA-enhanced MRI to differentiate between exudative and transudative pleural effusions. An MRI examination was performed on 22 patients with different types of pleural effusion (10 transudative and 12 exudative effusions). T1-weighted SE images were obtained before and 20 min after administration of Gd-DTPA (0.1 mmol/kg). The degree of enhancement of pleural effusions was evaluated both by visual assessment and by quantitative analysis of images. None of 10 transudative effusions showed significative enhancement, whereas 10 of 12 exudative effusions showed enhancement (sensitivity 83 %, specificity 100 %, positive predictive value 100 %). The postcontrast signal intensity ratios (SIRs) of exudates were significantly higher than corresponding precontrast ratios (P = 0. 0109) and the postcontrast SIRs of exudates were significantly higher than those of transudates (P = 0.0300). Exudative pleural effusions show a significant enhancement following administration of Gd-DTPA. We presume that this may be caused by increased pleural permeability and more rapid passage of a large amount of Gd-DTPA from the blood into the pleural fluid in case of exudative effusions. In our limited group of patients, signal enhancement proved the presence of an exudative effusion. Absence of signal enhancement suggests a transudate, but does not exclude an exudate.

[Blunt hepatic and splenic trauma: indications for conservative treatment based on computerized tomography]

In this paper the authors try to define CT criteria for the evaluation of hepatic and splenic injuries in blunt abdominal traumas, to suggest and guide the nonoperative management of trauma in hemodynamically stable patients. The predictive value of CT on the outcome of the nonoperative treatment in adult patients with blunt hepatic and splenic trauma is trusted more and more also thanks to the good results of conservative management in similar injuries in pediatric patients. Thus, we reviewed 314 emergency abdominal CT scans performed in our center March 1990 to March 1992. The hepatic and splenic injuries detected on CT scans were evaluated according to a CT-based injury classification in grades, with a score reflecting progressive severity of lesions. Moreover, the presence of intraperitoneal hemorrhage was determined and quantified on the basis of a standard classification system. Of 314 cases, CT revealed blunt hepatic injury in 17 patients and blunt splenic injury in 38. We excluded the patients who exhibited, besides the hepatic or splenic injury, other severe visceral lesions which might need surgery. Nonoperative management was attempted in 9 of 17 patients with hepatic injury and in 4 of 38 patients with splenic injury detected by CT; the scores given according to the above classification system were compared with the clinical outcome. The results indicate that hepatic injuries up to and including grade III, as assessed by CT, can be successfully managed without surgery in hemodynamically stable patients. As for splenic traumas, nonoperative management was attempted in a very small number of patients. Even though a case of grade-III splenic injury in our series was successfully treated without surgery, this may not be the rule, because the outcome of splenic injury and of intraperitoneal hemorrhage is often unpredictable.

[The magnetic resonance characteristics of rounded atelectasis]

Rounded atelectasis is a peculiar form of lung collapse which is well known by radiologists. Its appearance on conventional radiographs and CT is by now well recognized and widely reported. Even though these two techniques usually allow a diagnosis to be made, the MR appearance of rounded atelectasis is worth mentioning as well. This diagnostic imaging technique is widely employed, and our experience suggests that, in some cases, MR Imaging can give an important contribution to the study of this condition. We report our experience with 6 cases of rounded atelectasis in 5 patients (one patient had bilateral lesions). Five signs characteristic of rounded atelectasis were observed: some of them are seen on both conventional radiographs and CT scans, others are typical of the latter technique. All cases showed peripheral location of the lesions and the "comet tail" sign--i.e., vascular structures gently curving into the mass. These two signs are also observed on conventional radiographs and CT scans. Typical of MR imaging are the extant 3 signs: low signal in T1 and high signal in T2-weighted images in the whole of our cases; no signal from pleural thickening next to the mass in T2-weighted images, and, finally, the "kidney-like" pattern--i.e., hypointense lines converging toward the center of the mass. All these signs, which were always observed in our series, support the current etiopathogenetic hypothesis of pleural effusion as an early sign, which is reported to be followed by fibrous pleural involution which wraps atelectatic parenchyma up. On the basis of these typical MR features a correct diagnosis can usually be made even in those cases in which conventional radiography and CT do not allow a definite diagnosis.

Renal vein renin in renovascular hypertension: the experience of two Italian centers

A retrospective analysis of renal vein renin results has been done in 96 patients with renal artery stenosis and hypertension studied in two Italian centers (Sassari and Pisa) with respect to the outcome of either surgery or percutaneous transluminal angioplasty (PTA). In all patients the renal vein renin ratio and the V-A/A ratios for the affected and unaffected kidney were calculated. Each patient underwent surgery (75) of PTA (21): 71 subjects were cured, 17 improved whereas the arterial pressure did not vary after revascularisation procedure in 8 patients. In the Pisa series all 54 patients showed a lateralisation with contralateral renin suppression and 95% of them benefitted from surgery. In the Sassari series 42 patients were submitted to PTA or surgery, not only on the basis of a positive renal vein renin study but taking into account a complete clinical evaluation: 8 of them were cured or improved in spite of negative renal vein renin criteria. In the two series, the better predictive index appeared to be the suppression of the renin secretion from the contralateral kidney while the high/low renin ratio showed a consistent amount of false-positive and false-negative results. Our retrospective study demonstrates that the renal vein test in hypertensive patients with renal artery stenosis is highly predictive of the curability of the disease, particularly when contralateral suppression of renin secretion is present. On the other hand, since patients with negative renin indexes can also take benefit from surgery of PTA, the renin parameters cannot be adopted as the sole criterion in making the decision to operate.

Blunted adrenocorticotrophic hormone release during captopril treatment

High tissue levels of angiotensin II have been reported in the median eminence suggesting a possible role in the regulation of adrenocorticotrophic hormone (ACTH) secretion. To verify this hypothesis in man, the pituitary-adrenal axis response to hypoglycaemia was studied before and during captopril treatment in eight male essential hypertensive patients (stage I WHO; aged 35-52 years). Plasma levels of ACTH, cortisol and glucose were measured before and 60, 90 and 120 min after an intravenous bolus of normal saline as placebo an, 3 days later, after an intravenous bolus of rapidly acting insulin (0.1 IU/kg body weight). Captopril treatment was then started and both placebo and hypoglycaemic tests were repeated 15 days thereafter. No changes in ACTH, cortisol or glucose plasma levels were observed after acute normal saline, either before or during captopril administration. On the contrary, hypoglycaemia induced a sharp increase of ACTH plasma before captopril (from 27.7 +/- 11 to 131.30 +/- 26 pg/ml, P less than 0.01, 60 min after insulin) but not during angiotensin converting enzyme (ACE) inhibition (from 28.9 +/- 9 to 42.9 +/- 11 pg/ml, NS, at min 60 of the study). Our present data, showing a blunted ACTH response to hypoglycaemia during ACE inhibition, suggest that circulating angiotensin II may participate in the regulation of the release of the ACTH, possibly by a stimulation of angiotensin II receptors localized in the brain but outside the blood-brain barrier.

Plasma active and inactive renin and urinary kallikrein in normal subjects in response to hydrochlorothiazide, spironolactone or aldosterone administration

The aim of this study has been to see whether acute variations in the proportions of circulating active and inactive renin in normal subjects were related to concurrent changes in the excretion of urinary kallikrein. Hydrochlorothiazide (50 mg/day) was given to 6 normal volunteers for 6 days; another group of 6 normal subjects received spironolactone (300 mg/day) for 6 days whereas synthetic aldosterone (0.5 mg/day) was administered i.m. for three days to 3 normal subjects. Both diuretics induced a sharp rise in active and total renin and a significant transient decrease in inactive renin so that the active: total renin proportion significantly increased. Urinary kallikrein excretion did not significantly change in either group. Parenteral administration of aldosterone induced a striking fall in all renin components without changing the proportions of active and inactive renin whereas urinary kallikrein excretion increased. These results indicate that changes in active: total renin proportions can occur without parallel variations in urinary kallikrein excretion. The latter cannot be used, therefore, as a reliable index of the possible role of renal kallikrein as activator in-vivo of inactive renin in man.