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Pests in pastures have compromised the production of biomass for feeding livestock herds. Many strategies have been applied to sustainably solve this problem. One viable and innovative technique is the delivery of entomopathogenic fungi through endophytes. Therefore, this study aimed to (i) evaluate the endophytic capacity of two entomopathogenic fungi, Fusarium multiceps UFMGCB 11443 and Metarhizium anisopliae UFMGCB 11444, in Urochloa brizantha [(Hochst. ex A. Rich.) Stapf] (Poaceae) cultivar 'Marundu') via foliar inoculation or seed treatment, and (ii) measure their efficiency in controlling Mahanarva spectabilis Distant, 1909 (Hemiptera: Cercopidae) in U. brizantha. In the greenhouse, the fungi colonized the tissues of U. brizantha plants when inoculated via foliar spraying or seed treatment. The fungi F. multiceps and M. anisopliae caused 88% and 97.1% epizootic effects via seed inoculation, respectively, and 100% epizootic effects via foliar inoculation. In the field, the lowest fungal dose of 0.5 kg/ha had the same effect as a fourfold greater dose, with a >86% decrease in insect pest infestation observed. In summary, the fungi F. multiceps and M. anisopliae have endophytic effects and can effectively control M. spectabilis in U. brizantha pastures. [ABSTRACT FROM AUTHOR]

A 17-year-old male with no previous medical history was admitted 2 days before his death to a local hospital after mild dyspnea. Electrocardiography, chest radiography, and blood analysis revealed no abnormalities. Blood oxygen saturation was 99%, and SARS-CoV-2 nasopharyngeal swabs tested negative; thus, he was discharged without prescriptions. After 2 days, the subject died suddenly during a pool party. Forensic autopsy was performed analyzing all anatomical districts. Cardiac causes were fully excluded after deep macroscopic and microscopic evaluation; lung and brain analyses showed no macroscopic pathology. Finally, a large subglottic solid mass was detected. The whitish neoplasm showed an aggressive invasion pattern to the thyroid and adjacent deep soft tissues and occluded the trachea. High-power microscopy showed sheets of small, uniform cells with scant cytoplasm; round nuclei; and small, punctate nucleoli, with immunohistochemical expression of CK8-18, AE1/AE3, and CD99. Using FISH analysis, the break-apart molecular probes (EWSR1 (22q12) Break – XL, Leica Biosystem, Nussloch, Germany) showed distinct broken red and green fluorochromes, diagnostic of Ewing sarcoma. The neoplasm was characterized as adamantinoma-like Ewing sarcoma, and the mechanism of death was identified as airway obstruction. The rarity of the case resides in the circumstances of death, which pointed to the possibility of sudden unexpected death due to heart disease, but an oncological cause and the underlying mechanism were finally diagnosed. The best method to perform autopsies is still complete, extensive, and systematic macroscopic sampling of organs and districts followed by histopathological analysis, in addition to immunohistochemical and molecular investigations in those cases in which they are necessary. In fact, when neoplasms are detected, the application of advanced techniques such as immunohistochemistry and molecular diagnostics is fundamental to accurately certify death. [ABSTRACT FROM AUTHOR]

LISA [Linea Italiana per la Spettroscopia di Assorbimento X, Italian beamline for X-ray Absorption Spectroscopy (XAS)] is the Italian CRG (Collaborating Research Group) beamline at the ESRF (European Synchrotron Radiation Facility) dedicated to XAS [d'Acapito et al., J. Synchrotron Radiat. 26, 551–558 (2019)]. In this work, a methodical test of the LISA beamline in performing diffraction measurements is carried out. Synchrotron x-ray diffraction measurements would complement absorption spectroscopy techniques with the long-range characterization of the material under investigation, while XAS provides the short-range element selective information. [ABSTRACT FROM AUTHOR]

There is evidence showing that increasing the vertical dimension of occlusion, or interocclusal distance, reduces pain symptoms in patients with temporomandibular disorders (TMD) and bruxism. The mechanism underlying the analgesic effect is still under investigation. Some researchers propose either a gate mechanism or the activation of the trigemino-cardiac reflex. In this study, sensory and pain thresholds changes in the mandibular district have been evaluated in twenty healthy subjects immediately after 5 minutes of mandibular stretching at maximum opening of the jaw. Results showed a 60% increment in sensory threshold and a 70% increment in pain threshold (p<0.001) compared with the baseline values. The magnitude of the analgesic effect seems proportional to the extent of mandibular opening. These and similar results are discussed as for the implication in the treatment of TMD related symptoms. [ABSTRACT FROM AUTHOR]

Increasing occlusal vertical dimension (OVD) by means of oral splints is a practice widely used in the treatment of temporomandibular disorders (TMD), specifically myofascial pain, although the results are still uncertain. Oral splints with a vertical height that significantly exceeds the clinical rest position are considered by some researchers to be a better therapeutic solution in alleviating TMD symptoms than are "low" splints. In our observational study, 21 patients suffering from myofascial pain were examined for the effects of wearing a "high" oral splint while sleeping for 3 months. To ensure proper splint making, a mandibular stretching procedure was used to induce a relaxation of the patients' masticatory muscles and allow the correct alignment of the jaws. Results showed a marked increase of the interocclusal distance or "free space" (hence of OVD; from 0.64±0.53 mm to 1.42±0.76 mm, p<0.0001) measured by a kinesiograph, followed by a substantial reduction of the intensity of pain in oral and extraoral regions after using the splint. These results support the view that increasing OVD beyond the clinical rest position is not detrimental to patients' health. More importantly, high oral splints has been shown to be a promising therapeutic aid for the treatment of TMD and correlated pain syndromes. This clinical trial was registered on clinicaltrials.gov (Identifier: NCT02908568). [ABSTRACT FROM AUTHOR]

Background and purpose: Patients with a history of brain radiotherapy can experience acute stroke‐like syndromes related to the delayed effects of brain radiation, including stroke‐like migraine attacks after radiation therapy syndrome, peri‐ictal pseudoprogression and acute late‐onset encephalopathy after radiation therapy syndrome. The aim of this study was to collect evidence on the long‐term outcome and treatment of these conditions, whose knowledge is undermined by their rarity and fragmented description. Methods: Cases were collected, both prospectively and retrospectively, amongst six neuro‐oncology departments. Inclusion criteria were as follows: (i) history of brain radiotherapy (completed at least 6 months before the acute episode); (ii) new onset of acute/subacute neurological symptoms; (iii) exclusion of all etiologies unrelated to brain irradiation. A review of current literature on stroke‐like syndromes was performed to corroborate our findings. Results: Thirty‐two patients with acute neurological conditions attributed to the delayed effects of radiation were identified, including 26 patients with stroke‐like syndromes. Patients with stroke‐like syndromes commonly presented with a mosaic of symptoms, including focal deficits (77%), encephalopathy (50%), seizures (35%) and headache (35%). Seventy‐three percent of them had acute consistent magnetic resonance imaging alterations. Treatment included high‐dose steroids in 65% of cases. Twenty‐two patients recovered completely (85%). Sixteen patients (62%) experienced relapses (median follow‐up 3.5 years). A literature review identified 87 additional stroke‐like cases with similar characteristics. Conclusions: Stroke‐like events related to brain irradiation may be associated with permanent sequelae. Steroids are often administered on empirical grounds, as they are thought to accelerate recovery. Relapses are common, highlighting the need to elaborate adequate prevention strategies. [ABSTRACT FROM AUTHOR]

The combination of perfusion bioreactors with porous scaffolds is beneficial for the transport of cells during cell seeding. Nonetheless, the fact that cells penetrate into the scaffold pores does not necessarily imply the interception of cells with scaffold substrate and cell attachment. An in vitro perfusion system was built to relate the selected flow rate with seeding efficiency. However, the in vitro model does not elucidate how the flow rate affects the transport and deposition of cells onto the scaffold. Thus, a computational model was developed mimicking in vitro conditions to identify the mechanisms that bring cells to the scaffold from suspension flow. Static and dynamic cell seeding configurations were investigated. In static seeding, cells sediment due to gravity until they encounter the first obstacle. In dynamic seeding, 12, 120 and 600 μl/min flow rates were explored under the presence or the absence of gravity. Gravity and secondary flow were found to be key factors for cell deposition. In vitro and in silico seeding efficiencies are in the same order of magnitude and follow the same trend with the effect of fluid flow; static seeding results in higher efficiency than dynamic perfusion although irregular spatial distribution of cells was found. In dynamic seeding, 120 μl/min provided the best seeding results. Nevertheless, the perfusion approach reports low efficiencies for the scaffold used in this study which leads to cell waste and low density of cells inside the scaffold. This study suggests gravity and secondary flow as the driving mechanisms for cell-scaffold deposition. In addition, the present in silico model can help to optimize hydrodynamic-based seeding strategies prior to experiments and enhance cell seeding efficiency. [ABSTRACT FROM AUTHOR]

Aims Despite efforts to standardize histopathology practice through the development of guidelines, the interpretation of morphology is still hampered by subjectivity. We here describe Pathology Imagebase, a novel mechanism for establishing an international standard for the interpretation of pathology specimens. Methods and results The International Society of Urological Pathology ( ISUP) established a reference image database through the input of experts in the field. Three panels were formed, one each for prostate, urinary bladder and renal pathology, consisting of 24 international experts. Each of the panel members uploaded microphotographs of cases into a non-public database. The remaining 23 experts were asked to vote from a multiple-choice menu. Prior to and while voting, panel members were unable to access the results of voting by the other experts. When a consensus level of at least two-thirds or 16 votes was reached, cases were automatically transferred to the main database. Consensus was reached in a total of 287 cases across five projects on the grading of prostate, bladder and renal cancer and the classification of renal tumours and flat lesions of the bladder. The full database is available to all ISUP members at . Non-members may access a selected number of cases. Conclusions It is anticipated that the database will assist pathologists in calibrating their grading, and will also promote consistency in the diagnosis of difficult cases. [ABSTRACT FROM AUTHOR]

Background: The correlation between ALK gene copy number gain (ALK-CNG) and prognosis in the context of advanced non-small-cell lung cancer (NSCLC) remains a controversial issue. This study aimed to evaluate the association among ALK-CNG according to Fluorescent In Situ Hybridization (FISH), clinical characteristics and survival in resectable and advanced NSCLC.Methods: Clinical and pathological data of patients with resectable and advanced NSCLC were retrospectively collected. Tumor tissues were analyzed for ALK-CNG by FISH, and patients were divided in 3 groups/patterns on the basis of ALK signals: disomic [Pattern A], 3-7 signals [Pattern B], >7 signals [Pattern C]. The association between clinical and pathological features and ALK-CNG patterns was evaluated. Disease/progression-free and overall survival (DFS/PFS and OS) were estimated using the Kaplan-Meyer method.Results: A number of 128 (76.6 %) out of the 167 eligible patients were evaluable for ALK-CNG, displaying pattern A, B and C in 71 (42.5 %), 42 (25.1 %) and 15 (9 %) patients, respectively. Gains in ALK-CNG appear to be more frequent in smokers/former smokers than in non-smokers (74.2 % versus 20.4 %, respectively, p = 0.03). Pattern A and C seem more frequently associated with higher T-stage (T3-4), while pattern B appears more represented in lower T-stage (T 1-2) (p = 0.06). No significant differences in survival rate were observed among the above groups.Conclusions: A high ALK-CNG pattern might be associated with smoking status and theoretically it might mirror genomic instability. The implications for prognosis should be prospectively investigated and validated in larger patients' series.Trial Registration: We confirm that all the study was performed in accordance with relevant guidelines and regulations and that all the protocol (part of a larger project MFAG 2013 N.14282) was approved by the local Ethics Committee of the Azienda Ospedaliera Universitaria Integrata of Verona on November 11st, 2014. [ABSTRACT FROM AUTHOR]

Impact of the COVID-19 pandemic on melanoma diagnosis The magnitude of COVID-19's effect on the timely management of melanoma and nonmelanoma skin cancers. We thank Dr Luca Finizio, Dr Stefano Chincherini, Dr Paolo Rosina, Dr Gianpaolo Tessari for their contribution. [Extracted from the article]

Background:Adjuvant trastuzumab with chemotherapy is standard treatment for HER2-positive breast cancer, defined as either HER2 IHC3+ or IHC2+ and FISH amplified. The aim of this study was to investigate the degree to which HER2 amplification in terms of HER2 gene copy numbers in HER2+IHC2+ cancers affected the outcome in a community setting.Methods:Case records of 311 consecutive patients with early breast cancer presenting between 1st January 2005 and 31st December 2008 were reviewed. Progression-free survival and overall survival were calculated with the Kaplan-Meier method using STATA 13.Results:Among 3+ cases (n=230) 163 received T vs 67 no-T. Among 2+ cases (n=81) 59 received T vs 22 no-T. Among 59 IHC2+-treated cases n=28 had an average of >12, n=13 had >6 to <12, and n=18 had >2 to <6 HER2 gene copies, respectively. The time of progression and overall survival of high and low copy number patients was similar and better than the intermediate copy number and the untreated cohorts.Conclusions:High HER2 copy number (>12) appears to be associated with consistently better response compared with patients with intermediate HER2 copy numbers (6-12). In light of emerging data of patients showing insensivity to trastuzumab therapy, we propose that the HER2 gene copy number value should be included as an additional indicator for stratifying both the management and the follow-up of breast cancer patients. [ABSTRACT FROM AUTHOR]

The city Khara Khoto is located in the Gobi desert in Inner Mongolia. This city was deserted in the late 14th century and rediscovered in the beginning of the 20th century. In the present study, ceramic sherds typical for the Khara Khoto area have been analysed using neutrons, laboratory X-ray diffraction, synchrotron radiation X-ray diffraction as well as optical microscopy as complementary probes in extracting information on the mineral phase compositions as well as on the firing conditions during the pottery production. The data evaluation was performed with the standard diffraction analysis package GSAS and the new developed program AmPhOrAe. The dominating phase is mullite (~60 %) compared to a variable mixture of SiO quartz and cristobalite phases (~35 %) and feldspar as a minority phase. Refiring experiments on one of the sherds allow estimating the firing temperatures of the ceramics within the region of 1,150 and 1,250 °C. [ABSTRACT FROM AUTHOR]

Background Internet has become a significant resource for dissemination of medical information. We sought to investigate prevalence and usage patterns of Internet access among consecutive patients with cardiovascular diseases. Methods A cross-sectional study was performed using a questionnaire as study tool. Among patients with Internet access, the type of health information sought and the impact of these on daily life were assessed. Results Of 1063 patients invited to the study, 1000 patients [68% male gender, mean age 66 ± 11 years (range 27-83 years)] agreed to complete the questionnaire. 216/1000 (21.6%) used Internet to obtain information related to their disease. The patient education was graded as: low (15%), medium (66%) and high (19%). Reasons for Internet use were as follows: 24-h availability 142/216 (65.7%); free of charge 58/216 (26.9%); and anonymity 50/216 (23.2%). Younger (≤ 66 years) age (35.2% vs. 15.3%; p = 0.0001), male gender (24.6% vs. 15.4%; p = 0.001) and higher education level (49.4% vs. 16.1%; p = 0.001) were significantly associated with Internet use. 30.6% (66/216) of Internet users changed their individual health behaviour attributable to information found on the Internet. However, this was not related to age, gender or level of education (p = 0.5, p = 0.6 and p = 0.4, respectively). Patients without Internet use obtain health information mainly from the pharmacist (62%) or from their treating physician (58%). Conclusions A relevant number of patients with cardiovascular disease access the Internet for health information. The impact of such information on health-related behaviour in daily life was low. [ABSTRACT FROM AUTHOR]

BACKGROUND: Internet has become a significant resource for dissemination of medical information. We sought to investigate prevalence and usage patterns of Internet access among consecutive patients with cardiovascular diseases. METHODS: A cross-sectional study was performed using a questionnaire as study tool. Among patients with Internet access, the type of health information sought and the impact of these on daily life were assessed. RESULTS: Of 1063 patients invited to the study, 1000 patients [68% male gender, mean age 66 ± 11 years (range 27-83 years)] agreed to complete the questionnaire. 216/1000 (21.6%) used Internet to obtain information related to their disease. The patient education was graded as: low (15%), medium (66%) and high (19%). Reasons for Internet use were as follows: 24-h availability 142/216 (65.7%); free of charge 58/216 (26.9%); and anonymity 50/216 (23.2%). Younger (<= 66 years) age (35.2% vs. 15.3%; p = 0.0001), male gender (24.6% vs. 15.4%; p = 0.001) and higher education level (49.4% vs. 16.1%; p = 0.001) were significantly associated with Internet use. 30.6% (66/216) of Internet users changed their individual health behaviour attributable to information found on the Internet. However, this was not related to age, gender or level of education (p = 0.5, p = 0.6 and p = 0.4, respectively). Patients without Internet use obtain health information mainly from the pharmacist (62%) or from their treating physician (58%). CONCLUSIONS: A relevant number of patients with cardiovascular disease access the Internet for health information. The impact of such information on health-related behaviour in daily life was low. [ABSTRACT FROM AUTHOR]

The article presents a study of Hägg carbide (HC) regarding its rietveld refinements and pair distribution function (PDF) using synchrotron X-ray diffraction. It discusses the Fischer-Tropsch Synthesis (FTS) in the manufacturing process of hydrocarbons and oxygenated hydrocarbons from mixtures of carbon monoxide and hydrogen (syngas). It also gives structure determination of the carbides during the FTS conditions.

Piacentini GL, Bodini A, Peroni DG, Sandri M, Brunelli M, Pigozzi R, Boner AL. Nasal nitric oxide levels in healthy pre-school children. Pediatr Allergy Immunol 2010: 21: 1139-1145. © 2010 John Wiley & Sons A/S The evaluation of nasal nitric oxide (nNO) has been proposed as a screening tool in children with clinically suspectable primary ciliary dyskinesia. Nevertheless, normal values have been reported for school-aged children. This study was designed to identify normal nNO levels in pre-school children. nNO was assessed in 300 healthy children aged between 1.5 and 7.2. Two hundred and fifty of them were unable to fulfill the guideline requirements for nNO measurement and were assessed by sampling the nasal air continuously with a constant trans-nasal aspiration flow for 30 s during tidal breathing. For those children who were able to cooperate, the average nNO concentration was calculated according to guidelines. A statistically significant relationship between nNO level and age was demonstrated in this study group of pre-school children (p < 0.001). An increase in nNO of about 100 ppb was observed in children older than 6 yr vs. those aged <3. This study presents a description of normal nNO values in pre-school children. The effect of the age and the eventual presence of rhinitis and snoring need to be considered whenever nNO is evaluated in the clinical practice, in particular in non-cooperative children. [ABSTRACT FROM AUTHOR]

Types 1 and 2 by Delahunt of papillary renal cell carcinoma (PRCC) are traditionally differentiated. An oncocytic variant of PRCC (O-PRCC) has recently been described. We compare clinical data of O-PRCC with other subtypes of PRCC such as the main tumour size, necrotic changes, presence of pseudocapsula and real extrarenal growth in retrospective study. From 1/1992 to 10/2009, 1,398 patients with 1,436 renal tumours were surgically treated in our institution. PRCCs were described in 109 (7.6%). Among PRCC, O-PRCCs were in 12 (11%), PRCC type 1 in 86 (78.9%), PRCC type 2 in 8 (7.3%) and others in 3 (2.8%) cases. The patient’s mean age with O-PRCC (M:F ratio = 2:1) was 67.5 ± 10.9 versus 63.5 ± 14.1 in type 1 and 57.9 ± 5.7 in type 2, the mean tumour size was 35 ± 12 mm versus 47 ± 22 and 37 ± 17, respectively. The follow-up of O-PRCC is 35.3 ± 12.3 months and all cases are without recurrence. We did not find any pseudocapsula in O-PRCC but it was a major sign of PRCC type 1 (32.6%). Huge microscopic necrotic changes were described in 33.3% of O-PRCC, in 33.7% of PRCC type 1 and 62.5% of PRCC type 2. Extrarenal growth was found only in 16.7% O-PRCC versus 40.7% in PRCC type I. None of the O-PRCC had pseudocapsula and none had massive necroses in comparison of O-PRCC with PRCC types I and II. Extrarenal growth in O-PRCC is relatively rare. The malignant potential of O-PRCC is low. [ABSTRACT FROM AUTHOR]

The lattice parameter for polycrystalline diamond is determined as a function of temperature in the 4-300 K temperature range. In the range studied, the lattice parameter, expressed in angstrom units, of the studied sample increases according to the equation a = 3.566810(12) + 6.37(41) × 10-14T4 (approximately, from 3.5668 to 3.5673 Å). This increase is larger than that earlier reported for pure single crystals. The observed dependence and the resulting thermal expansion coefficient are discussed on the basis of literature data reported for diamond single crystals and polycrystals. [ABSTRACT FROM AUTHOR]

Structural studies done on HgSe nanoclusters fabricated in the pores of two types of zeolite frameworks, LTL (tubular pore) and Nd-Y (nearly spherical pore), are presented. Nanoclusters were synthesized in these zeolite frameworks via chemical vapor deposition. Anomalous X-ray scattering (AXS) studies were performed on both HgSe/zeolite-Y and HgSe/zeolite-L systems. As a result, we present two distinct structural models for NdY/HgSe and LTL/HgSe systems. A remarkable feature present in our X-ray diffraction (XRD) patterns, diffuse scattering, will also be discussed using our initial results of the atomic pair distribution function (PDF) studies. X-ray structural work is complemented using the results of optical and Raman studies. [ABSTRACT FROM AUTHOR]

High resolution synchrotron radiation X-ray powder diffraction was used to investigate the melting of the cooperative Jahn-Teller distortion (cJTd) in a perovskite of composition KCu0.8Mg0.2F3. A first order phase transition relaxing the cJTd is observed at T ∼ 600 K. From the transition temperature, an estimation of kT is derived ( kT = 0.05 eV) for the cJTd in the doped compound. This is the very first observation of cJTd melting in a compound of the series KCu1− x Mg x F3. A structural phase diagram for the Cu rich zone of the series is proposed. In principle, the extension of this experimental investigation could be used to disentangle the orbital order (OO) and cJTd energy scales in the parent compound KCuF3, a test system for OO theories. [ABSTRACT FROM AUTHOR]

The structural phase transition from aragonite to calcite in biogenic samples extracted from the skeletons of selected scleractinian corals has been studied by synchrotron radiation diffraction. Biogenic aragonite samples were extracted en bloc without pulverization from two ecologically different scleractinian taxa: Desmophyllum (deep-water, solitary and azooxanthellate) and Favia (shallow-water, colonial, zooxanthellate). It was found that natural (not pulverized) samples contribute to narrow Bragg peaks with Δ d/ d values as low as 1 × 10−3, which allows the exploitation of the high resolution of synchrotron radiation diffraction. A precise determination of the lattice parameters of biogenic scleractinian coral aragonite shows the same type of changes of the a, b, c lattice parameter ratios as that reported for aragonite extracted from other invertebrates [Pokroy, Quintana, Caspi, Berner & Zolotoyabko (2004). Nat. Mater. 3, 900–902]. It is believed that the crystal structure of biogenic samples is influenced by interactions with organic molecules that are initially present in the biomineralization hydrogel. The calcite phase obtained by annealing the coral samples has a considerably different unit-cell volume and lattice parameter ratio c/ a as compared with reference geological calcite and annealed synthetic aragonite. The internal strain in the calcite structure obtained by thermal annealing of the biomineral samples is about two times larger than that found in the natural aragonite structure. This effect is observed despite slow heating and cooling of the sample. [ABSTRACT FROM AUTHOR]

The thermal lattice expansion in the superconducting Mg1− x Al x B2 system ( x = 0, 0.13, and 0.59) has been measured using high-resolution X-ray powder diffraction. An unusual large negative thermal expansion (NTE) appears for temperatures below T * = 60 K in the MgB2. The NTE effect increases in Mg0.87Al0.13B2 and disappears at high Al content in the Mg0.59Al0.41B2 where the temperature dependence of volume follows a standard Einstein model in the whole temperature range. The anomalous behavior of the thermal expansion provides a direct evidence in the physics of diborides for the relevance of the proximity to the 2.5 Lifshitz electronic topological transition where the Fermi surface of the σband changes from a two-dimensional (2D) to a three-dimensional (3D) topology. [ABSTRACT FROM AUTHOR]

The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic (2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in 77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2. The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives) the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization and/or cardiac surgery. [ABSTRACT FROM AUTHOR]

In hippocampal pyramidal cells (HPCs), Dopamine (DA) application (1 μM) produced, in 50% of recorded cells, an hyperpolarization of the resting membrane potential (r.m.p.) and an increase of the afterhyperpolarization (AHP) amplitude and duration in 79% of recorded cells. DA-induced effects on both the r.m.p. and AHP were mimicked by bath application of a D-l selective agonist, SKF 38393 (20 μM). In addition, we have observed that a D-l selective antagonist such as SCH 23390 (1 μ,M) abolished the action of both DA and SKF 38393. In contrast, the activation of D-2 receptors through LY 171555 (10 μm) produced, in 50% of cells, a depolarization of the r.m.p. and a depression of the AHP in 67% of recorded cells. These results suggest that the effects observed in hippocampal pyramidal neurons after DA application of micromolar concentration are mediated by D-1 subtype of receptors. [ABSTRACT FROM AUTHOR]

It is possible to obtain habituation of swim induction by stimulating the leech with repetitive light electrical trains. After obtaining this simple form of nonassociative learning, it is also possible to potentiate its response by a series of nociceptive skin brushings (dishabituation). Serotonin applied to the animal is the only neurotransmitter found to mimick dishabituation. We have observed that in the period April-June most animals did not exhibit potentiation of the swimming response after nociceptive stimulation while injection of serotonin mimicked dishabituation as in the animals treated in the period October-March. We have seen correlation between the changes in nonassociative learning and the seasonal variation of serotonin levels in segmental ganglia. This finding strengthens the hypothesis of serotonin as the neurotransmitter mediating dishabituation in swim induction of the leech. [ABSTRACT FROM AUTHOR]

Mn K-edge X-ray absorption near edge structure (XANES) measurements have been made to study the temperature-dependent lattice effects in the La0.75Ca0.25MnO3 system. The high-resolution XANES spectra recorded with high signal-to-noise ratio have allowed us to study the temperature dependence of the Jahn-Teller splitting indicated directly by the dipole forbidden pre-peaks corresponding to transition in Mn 3 d states. The results show splitting of the e g state in its two orbitals ( d x2 -y 2 and d 3z 2-r 2. The energy splitting shows anomalous temperature dependence across the giant magnetoresistance transition temperature. [ABSTRACT FROM AUTHOR]

The shape resonance of the superconducting gap for a 2D electron gas in a superlattice of quantum stripes with a finite 1 D periodic potential barrier is studied when the Fermi level is tuned near the bottom of the third superlattice subband. The maximum T c . appears at a critical charge density T c . For p > p c (in the underdoped regime) the chemical potential is tuned in a pseudogap region characterized by a decrease of the density of states and an opening of the partial gap at the Fermi surface. The pseudogap is closed for p< p c (in the overdoped regime). [ABSTRACT FROM AUTHOR]

Recent studies have shown that structural instabilities play a vital role in high- T c superconductivity. We have used a local structural probe, extended X-ray absorption fine structure (EXAFS), to investigate the instability of the CuO2 plane in La-based high- T c perovskite systems. Temperature-dependent Cu K-edge EXAFS spectra measured on single crystals of La1.85Sr0.15CuO4 (LSCO) and La2CuO4.1 (LCO) show a characteristic temperature ( T ls ) where the local structure of the system diverges from the average one. This temperature coincides with a crossover temperature where the system shows anomalous metal-insulator transition in transport measurements. We have discussed the EXAFS results as an evidence for a particular phase transition of the system with segregation of localized and itinerant charge carriers in a short coherence charge density wave (CDW). A phase diagram for this CDW has been proposed. [ABSTRACT FROM AUTHOR]