A 2D ferroelectric vortex pattern in twisted BaTiO3 freestanding layers.

The wealth of complex polar topologies1-10 recently found in nanoscale ferroelectrics results from a delicate balance between the intrinsic tendency of the materials to develop a homogeneous polarization and the electric and mechanical boundary conditions imposed on them. Ferroelectric-dielectric interfaces are model systems in which polarization curling originates from open circuit-like electric boundary conditions, to avoid the build-up of polarization charges through the formation of flux-closure11-14 domains that evolve into vortex-like structures at the nanoscale15-17 level. Although ferroelectricity is known to couple strongly with strain (both homogeneous18 and inhomogeneous19,20), the effect of mechanical constraints21 on thin-film nanoscale ferroelectrics has been comparatively less explored because of the relative paucity of strain patterns that can be implemented experimentally. Here we show that the stacking of freestanding ferroelectric perovskite layers with controlled twist angles provides an opportunity to tailor these topological nanostructures in a way determined by the lateral strain modulation associated with the twisting. Furthermore, we find that a peculiar pattern of polarization vortices and antivortices emerges from the flexoelectric coupling of polarization to strain gradients. This finding provides opportunities to create two-dimensional high-density vortex crystals that would enable us to explore previously unknown physical effects and functionalities.

Patient-reported outcomes before treatment for localized prostate cancer: are there differences among countries? Data from the True North Global Registry.

INTRODUCTION: Similar Patient-Reported Outcomes (PROs) at diagnosis for localized prostate cancer among countries may indicate that different treatments are recommended to the same profile of patients, regardless the context characteristics (health systems, medical schools, culture, preferences…). The aim of this study was to assess such comparison. METHODS: We analyzed the EPIC-26 results before the primary treatment of men diagnosed of localized prostate cancer from January 2017 onwards (revised data available up to September 2019), from a multicenter prospective international cohort including seven regions: Australia/New Zealand, Canada, Central Europe (Austria / Czech Republic / Germany), United Kingdom, Italy, Spain, and the United States. The EPIC-26 domain scores and pattern of three selected items were compared across regions (with Central Europe as reference). All comparisons were made stratifying by treatment: radical prostatectomy, external radiotherapy, brachytherapy, and active surveillance. RESULTS: The sample included a total of 13,483 men with clinically localized or locally advanced prostate cancer. PROs showed different domain patterns before treatment across countries. The sexual domain was the most impaired, and the one with the highest dispersion within countries and with the greatest medians' differences across countries. The urinary incontinence domain, together with the bowel and hormonal domains, presented the highest scores (better outcomes) for all treatment groups, and homogeneity across regions. CONCLUSIONS: Patients with localized or locally advanced prostate cancer undergoing radical prostatectomy, EBRT, brachytherapy, or active surveillance presented mainly negligible or small differences in the EPIC-26 domains before treatment across countries. The results on urinary incontinence or bowel domains, in which almost all patients presented the best possible score, may downplay the baseline data role for evaluating treatments' effects. However, the heterogeneity within countries and the magnitude of the differences found across countries in other domains, especially sexual, support the need of implementing the PRO measurement from diagnosis.

Determination of Anti-Anisakis Simplex Antibodies and Relationship with αß and γδ Lymphocyte Subpopulations in Patients with Crohn's Disease.

BACKGROUND: The etiology of Crohn's disease (CD) is still unknown although new theories are based on defects in innate immunity. We have previously shown a decrease in γδ T cells in CD patients. Previous studies have shown a high prevalence of anti-A. simplex immunoglobulins in CD patients. The diminution of γδ T cells in the peripheral blood and intestinal mucosa of CD patients may create a state of immunosuppression that would facilitate A. simplex infection. AIMS: To study the antibody responses to Anisakis antigens in Crohn's disease patients and its relationship with αß and γδ T cell subsets. METHODS: We recruited 81 CD patients and 81 healthy controls. αß and γδ T cell subsets and anti-A. simplex antibodies were measured. RESULTS: Levels of anti-A. simplex IgG and IgM were significantly increased in CD patients. Almost 20% of CD patients were positive for IgG and IgM anti-A. simplex versus only 3.7 and 2.5%, respectively, in normal subjects. However, lower specific IgA levels were observed in the group of CD patients versus healthy subjects. We found an association between CD3 + CD8 + Î³Î´ subset and IgM anti-A. simplex levels. In ileal cases and stricturing behavior of CD, we observed the highest levels of specific antibodies with the exception of anti-A. simplex IgA. CONCLUSIONS: The relationship of specific antibodies with a γδ T cell deficiency makes these cell candidates to play a role in the immune response against Anisakis. In addition, anti-Anisakis antibodies could be considered as markers of risk of progression in CD.

Comparative measurements of bone mineral density and bone contrast values in canine femora using dual-energy X-ray absorptiometry and conventional digital radiography.

BACKGROUND: Aseptic loosening due to bone remodelling processes after total hip replacement is one common cause for revision surgery. In human medicine, dual-energy X-ray absorptiometry (DEXA) is the gold standard for quantitative evaluation of bone mineral density, whereas in veterinary medicine conventional radiography is used for follow-up studies. Recently, a method has been described using digital X-ray images for quantitative assessment of grey scale values of bone contrast. Therefore, the aim of the present study was to evaluate the correlation of bone mineral density (BMD) measured by DEXA with grey scale values (GV) measured in digital X-ray images (RX50, RX66) ex vivo. RESULTS: The measured GV in the chosen X-ray settings showed on average a good correlation (r = 0.61) to the measured BMD with DEXA. Correlation between the two X-ray settings was very good (r = 0.81). For comparisons among regions of interests (ROIs) a difference of 8.2% was found to be statistically significant, whereas in the case of RX50 and RX66 differences of 5.3% and 4.1% were found to be statistically significant. CONCLUSIONS: Results indicate that measuring absolute changes in bone mineral density might be possible using digital radiography. Not all significant differences between ROIs detectable with DEXA can be displayed in the X-ray images because of the lower sensitivity of the radiographs. However, direct comparison of grey scale values of the periprosthetic femur in one individual patient during the follow-up period, in order to predict bone remodelling processes, should be possible, but with a lesser sensitivity than with DEXA. It is important that the same X-ray settings are chosen for each patient for follow-up studies.

Refractometric sensing with fluorescent-core microcapillaries.

Capillaries present a promising structure for microfluidic refractive index sensors. We demonstrate a capillary-type fluorescent core microcavity sensor based on whispering gallery mode (WGM) resonances. The device consists of a microcapillary having a layer of fluorescent silicon quantum dots (QDs) coated on the channel surface. The high effective index of the QD layer confines the electric field near the capillary channel and causes the development of WGM resonances in the fluorescence spectrum. Solutions consisting of sucrose dissolved in water were pumped through the capillary while the fluorescence WGMs were measured with a spectrometer. The device showed a refractometric sensitivity of 9.8 nm/RIU (up to 13.8 nm/RIU for higher solution refractive index) and a maximum detection limit of ~7.2 x 10(-3) RIU. Modeling the field inside the capillary structure, which is analogous to a layered hollow ring resonator, shows that sensitivities as high as 100 nm/RIU and detection limits as low as ~10(-5) RIU may be achievable by optimizing the QD film thickness.

Excitation and interrogation of whispering-gallery modes in optical microresonators using a single fused-tapered fiber tip.

We show that whispering-gallery modes (WGMs) in optical microresonators can be excited and detected using a fused-tapered fiber tip (FTFT). The fabrication of FTFTs is simple and inexpensive; they are robust and allow the excitation and interrogation of the resonances with a single fiber. Excitation of high-Q WGMs in silica microcylinders and microspheres is demonstrated.

Transcript abundance of amino acid transporters, ß-casein, and α-lactalbumin in mammary tissue of periparturient, lactating, and postweaned sows.

The objective of these experiments was to test the hypothesis that transcript abundance of cationic AA transporter- and milk protein-encoding genes increase in the porcine mammary gland in response to higher lactation demand. Genes of interest included those encoding for the milk proteins α-lactalbumin (α-LA) and ß-casein (ß-CN; LALBA and CSN2, respectively), and AA transporter b(0,+)AT, y(+)LAT1, y(+)LAT2, ATB(0,+), CAT-1, and CAT-2b (SLC7A9, SLC7A7, SLC7A6, SLC6A14, SLC7A1, and SLC7A2, respectively). Mammary tissue was biopsied from 4 sows on d 110 of gestation (prepartum), on d 2 (early postpartum), on d 5 (early), and d 17 (peak) of lactation, and on d 5 after weaning (postweaning), and mRNA of target genes quantified by reverse transcription quantitative PCR. Compared with prepartum, CAT-1, ATB(0,+), y(+)LAT2, ß-CN, and α-LA mRNA abundance was higher at early lactation, whereas compared with early lactation, only CAT-1 and α-LA mRNA abundance was higher at peak lactation. The CAT-2b, y(+)LAT1, and b(0,+)AT mRNA abundance did not differ when comparing either prepartum or peak lactation to early lactation. Compared with peak lactation, postweaning mRNA abundance of CAT-1, ATB(0,+), α-LA, and ß-CN decreased, y(+)LAT2, CAT-2b, and b(0,+)AT remained unchanged, and y(+)LAT1 increased. The mRNA abundance of y(+)LAT2 increased from early postpartum to early lactation, and remained unchanged for CAT-1, ATB(0,+), α-LA, and ß-CN. From prepartum to peak lactation, the mRNA abundance of CAT-1, y(+)LAT2, and ATB(0,+) was positively correlated with that of ß-CN and α-LA. In conclusion, the expression of genes encoding for y(+)LAT1, CAT-2b, and b(0,+)AT remained unchanged in porcine mammary glands over prepartum to peak lactation period, whereas expression of genes encoding for CAT-1, ATB(0,+), and y(+)LAT2 was upregulated and positively correlated to expression of genes encoding for the mammary synthesized milk proteins ß-CN and α-LA.

Challenges and opportunities to prevent tuberculosis in people living with HIV in low-income countries.

People living with the human immunodeficiency virus (HIV) (PLHIV) are at high risk for tuberculosis (TB), and TB is a major cause of death in PLHIV. Preventing TB in PLHIV is therefore a key priority. Early initiation of antiretroviral therapy (ART) in asymptomatic PLHIV has a potent TB preventive effect, with even more benefits in those with advanced immunodeficiency. Applying the most recent World Health Organization recommendations that all PLHIV initiate ART regardless of clinical stage or CD4 cell count could provide a considerable TB preventive benefit at the population level in high HIV prevalence settings. Preventive therapy can treat tuberculous infection and prevent new infections during the course of treatment. It is now established that isoniazid preventive therapy (IPT) combined with ART among PLHIV significantly reduces the risk of TB and mortality compared with ART alone, and therefore has huge potential benefits for millions of sufferers. However, despite the evidence, this intervention is not implemented in most low-income countries with high burdens of HIV-associated TB. HIV and TB programme commitment, integration of services, appropriate screening procedures for excluding active TB, reliable drug supplies, patient-centred support to ensure adherence and well-organised follow-up and monitoring that includes drug safety are needed for successful implementation of IPT, and these features would also be needed for future shorter preventive regimens. A holistic approach to TB prevention in PLHIV should also include other important preventive measures, such as the detection and treatment of active TB, particularly among contacts of PLHIV, and control measures for tuberculous infection in health facilities, the homes of index patients and congregate settings.

Application of optical action potentials in human induced pluripotent stem cells-derived cardiomyocytes to predict drug-induced cardiac arrhythmias.

INTRODUCTION: Human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) are emerging as new and human-relevant source in vitro model for cardiac safety assessment that allow us to investigate a set of 20 reference drugs for predicting cardiac arrhythmogenic liability using optical action potential (oAP) assay. METHODS: Here, we describe our examination of the oAP measurement using a voltage sensitive dye (Di-4-ANEPPS) to predict adverse compound effects using hiPS-CMs and 20 cardioactive reference compounds. Fluorescence signals were digitized at 10kHz and the records subsequently analyzed off-line. Cells were exposed to 30min incubation to vehicle or compound (n=5/dose, 4 doses/compound) that were blinded to the investigating laboratory. Action potential parameters were measured, including rise time (Trise) of the optical action potential duration (oAPD). RESULTS: Significant effects on oAPD were sensitively detected with 11 QT-prolonging drugs, while oAPD shortening was observed with ICa-antagonists, IKr-activator or ATP-sensitive K+ channel (KATP)-opener. Additionally, the assay detected varied effects induced by 6 different sodium channel blockers. The detection threshold for these drug effects was at or below the published values of free effective therapeutic plasma levels or effective concentrations by other studies. DISCUSSION: The results of this blinded study indicate that OAP is a sensitive method to accurately detect drug-induced effects (i.e., duration/QT-prolongation, shortening, beat rate, and incidence of early after depolarizations) in hiPS-CMs; therefore, this technique will potentially be useful in predicting drug-induced arrhythmogenic liabilities in early de-risking within the drug discovery phase.

The Use of Ratiometric Fluorescence Measurements of the Voltage Sensitive Dye Di-4-ANEPPS to Examine Action Potential Characteristics and Drug Effects on Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) and higher throughput platforms have emerged as potential tools to advance cardiac drug safety screening. This study evaluated the use of high bandwidth photometry applied to voltage-sensitive fluorescent dyes (VSDs) to assess drug-induced changes in action potential characteristics of spontaneously active hiPSC-CM. Human iPSC-CM from 2 commercial sources (Cor.4U and iCell Cardiomyocytes) were stained with the VSD di-4-ANEPPS and placed in a specialized photometry system that simultaneously monitors 2 wavebands of emitted fluorescence, allowing ratiometric measurement of membrane voltage. Signals were acquired at 10 kHz and analyzed using custom software. Action potential duration (APD) values were normally distributed in cardiomyocytes (CMC) from both sources though the mean and variance differed significantly (APD90: 229 ± 15 ms vs 427 ± 49 ms [mean ± SD, P < 0.01]; average spontaneous cycle length: 0.99 ± 0.02 s vs 1.47 ± 0.35 s [mean ± SD, P < 0.01], Cor.4U vs iCell CMC, respectively). The 10-90% rise time of the AP (Trise) was ∼6 ms and was normally distributed when expressed as 1/[Formula: see text] in both cell preparations. Both cell types showed a rate dependence analogous to that of adult human cardiac cells. Furthermore, nifedipine, ranolazine, and E4031 had similar effects on cardiomyocyte electrophysiology in both cell types. However, ranolazine and E4031 induced early after depolarization-like events and high intrinsic firing rates at lower concentrations in iCell CMC. These data show that VSDs provide a minimally invasive, quantitative, and accurate method to assess hiPSC-CM electrophysiology and detect subtle drug-induced effects for drug safety screening while highlighting a need to standardize experimental protocols across preparations.

Before viability: a geographically based outcome study of infants weighing 500 grams or less at birth.

OBJECTIVE: The primary objective of this study was to determine the likelihood of long-term survival and avoidance of disabilities in a geographically based population of infants born at 20 weeks gestation or more and weighing 500 g or less at birth. STUDY DESIGN: This was a 12-year historical cohort follow-up study of all infants born in this gestational age and birth weight category in the Province of Alberta, Canada, between 1983 and 1994. Data were collected from certificates of live births or stillbirths, death certificates, hospital records, and longitudinal multidisciplinary follow-up examinations. RESULTS: One thousand one hundred ninety-three infants were of 20 weeks gestation or more, weighed 500 g or less, and were born between 1983 and 1994. Eight hundred eleven (68.0%) were stillborn and 382 (32.0%) were born alive. Among the latter, neonatal intensive care was provided in 113 (29.6%) and withheld in 269 (70.4%). The infants receiving intensive care were of heavier birth weight, later gestational age, higher antenatal risk scores, were more likely to be born in a level III center, to have received antenatal steroids, and to have been delivered by cesarean section. Of the infants receiving intensive care, 95 (84. 1%) died and 18 (15.9%) were discharged alive, but 5 of these died after discharge because of respiratory complications. The infants discharged alive had later gestational age, were more likely to be small for gestational age, singletons, treated with antenatal steroids, and to have been delivered by cesarean section. Maternal indications were described in the majority of cesarean sections done for live-born infants. The 13 infants who were long-term survivors were followed at ages 12 and 36 months adjusted age. Four had no serious disabilities, 4 had one disability (cerebral palsy or mental retardation), and 5 had multiple disabilities (cerebral palsy plus mental retardation with blindness in 2 cases and deafness in 1 case). CONCLUSION: The majority of infants born at gestational age 20 weeks or more weighing <500 g were stillborn. Among live births, neonatal intensive care was withheld in 70% and initiated in 30%. Of the latter, 11% survived to 36 months of age, and of these, 4 infants (31%), most of whom are small for gestational age, female infants, avoided major disabilities but 9 (69%) had one or more major disabilities. Survivors are prone to rehospitalizations early in life, slow growth, feeding problems, and minor visual difficulties; rates of learning-related and behavioral problems at school age are not yet known. Implications. Parents and caregivers faced with the impending delivery of an infant in this gestational age/birth weight category should understand that survival without multiple major disabilities is possible but rare. They should be made aware of local population-based results and not just isolated reports.

Peroxidase activity and estradiol receptors in human breast cancer.

In order to establish the relation between peroxidase activity in human breast carcinoma and its estrogen-dependency, estradiol receptors and their peroxidase activities were determined by a very sensitive fluorimetric method in 61 carcinomas. The geometrical mean of peroxidase activity in the 34 estradiol receptor negative carcinomas, 12.8 mU/g tissue, was significantly higher (p less than 0.05) than that of the 27 estradiol receptor positive cases, with a mean of 10.57 mU/g tissue. Necrosis and/or inflammation were found more frequently in the estradiol receptor negative carcinomas (p less than 0.01) than in the estradiol receptor positive. It is concluded that peroxidase activity is linked more to the typical biological behavior of the tumor than to tumoral estrogen-dependency. Thus, the estradiol receptor negative tumors, which showed a more aggressive behavior associated with frequent necrosis and intratumoral inflammatory signs, had a greater peroxidase activity.

Cierre de un gran defecto de la pared torácica y abdominal usando omento y malla de polipropileno en un canino / Closure of a large thoracic and abdominal wall defect using omentum and a polypropylene mesh in a dog

RESUMEN Este reporte de caso describe la resección quirúrgica exitosa de un condroma de gran tamaño localizado en las dos últimas costillas y pared abdominal craneal izquierda de un canino, usando una malla de polipropileno, omento y avance del diafragma. Se discute la técnica quirúrgica y los materiales utilizados en el procedimiento, así como la evolución posquirúrgica del paciente.

ABSTRACT This case report describes the successful surgical resection of a large chondroma located in the last two ribs and left cranial abdominal wall of a dog, using a polypropylene mesh, omentum and diaphragm advance. The surgical technique and the materials used in the procedure, as well as the postoperative outcome, are discussed.

[Classification of canine intervertebral disc degeneration using high-field magnetic resonance imaging and computed tomography]. / Klassifikation der Bandscheibendegeneration des Hundes in der nativen Computertomographie und der Hochfeld-Magnetresonanztomographie.

OBJECTIVE: Although the classification of canine intervertebral disc degeneration using magnetic resonance imaging (MRI) has been described in the literature, there is no such classification using computed tomographic imaging. Because computed tomography (CT) is a frequently used diagnostic imaging tool in veterinary medicine, the aim of this study was the introduction and validation of such a scoring system. T2-weighted magnetic resonance images were available for comparative analysis. MATERIAL AND METHODS: A total of 43 dogs were examined using CT and MRI. Image data records of 144 intervertebral discs were blinded, randomized and evaluated twice by three observers. CT data were analyzed using a self-developed scoring system, while MRI data sets were evaluated using the Pfirrmann scoring system. Intra- and interobserver agreement were determined using Statistical Analysis Software (SAS). RESULTS: Intra- and interobserver agreement were mostly substantial in the Pfirrmann (0.58-0.77) and self-developed (0.60-0.81) scoring systems. A slight agreement was found between both classification systems (κ scores 0.26-0.29). CONCLUSION AND CLINICAL RELEVANCE: The self-developed scoring system allows a reliable assessment of canine intervertebral disc degeneration using CT imaging. Therefore, further diagnostic and prognostic information can be obtained. Degenerative changes in the intervertebral discs could be identified at an earlier stage when using MRI in comparison with CT.

Predicting fat quality from pigs fed reduced-oil corn dried distillers grains with solubles by near infrared reflectance spectroscopy: fatty acid composition and iodine value.

This study tested the ability of near infrared reflectance spectroscopy (NIRS) to estimate the fatty acid (FA) composition and iodine value (IV) of backfat from carcasses of pigs fed reduced-oil corn dried distillers grains with solubles. NIRS was suitable for screening purposes for the proportions of total saturated, monounsaturated, polyunsaturated, n-3 and n-6 FAs and some individual FAs such as C16:0, C18:1, C18:2n-6 and C18:3n-3 (R(2)=0.80-0.89; RMSECVs, root mean square errors of cross-validation=0.21-1.37% total FA) in both cold and warm intact backfat samples. This technology also met the requirements for a quick screening for the backfat IV in both cold and warm intact samples (R(2)=0.90 and 0.87; RMSECVs=1.66 and 1.80% total FA, respectively), which would help provide differential feed-back to pig producers and the feed industry and may provide the opportunity for breeding pigs for a desirable fat quality.

Effect of amino acids supply in reduced crude protein diets on performance, efficiency of mammary uptake, and transporter gene expression in lactating sows.

To test the hypothesis that reduction in dietary CP concentration coupled with crystalline AA inclusion increases the efficiency of AA use for milk production, mammary AA arteriovenous concentration differences (A-V), AA transport efficiency (A-V/A × 100), and transcript abundance of AA transporters and milk protein genes were determined in lactating sows fed 1 of 3 diets containing 9.5% (Deficient), 13.5% (Ideal), or 17.5% (Standard) CP, with a similar profile of indispensable and dispensable AA. On d 7 and 18, arterial and mammary venous blood and mammary tissue were sampled postfeeding. Transcript abundance of AA transporters b(0,+)AT (SLC7A9), y(+)LAT2 (SLC7A6), ATB(0,+) (SLC6A14), CAT-1 (SLC7A1), and CAT-2b (SLC7A2) and milk protein ß-casein (CSN2) and LALBA (α-lactalbumin) were determined using reverse transcription quantitative PCR. Piglet ADG increased curvilinearly (linear and quadratic, P < 0.03) with increasing percent CP from Deficient to Standard. On d 7, Lys and Arg A-V and transport efficiency increased quadratically (P < 0.05) with increasing percent CP. On d 18, Lys A-V tended to increase (linear, P = 0.08) with increasing percent CP. Increasing CP increased Ile and Val A-V on d 7 (linear, P = 0.05 and P = 0.08, respectively) and Leu and Val on d 18 (linear, P = 0.07 and P = 0.04, respectively). On d 7, plasma concentrations of branched chain AA (BCAA):Lys decreased quadratically (P < 0.05). Expression of genes SLC7A9, SLC7A6, SLC6A14, SLC7A1, SLC7A2, CSN2, and LALBA was unaffected by diet. In conclusion, decreasing the dietary CP from 17.5% to 13.5% with inclusion of crystalline AA did not affect piglet ADG, AA transporter, or milk protein gene expression but increased mammary transport efficiency and A-V of Lys and Arg on d 7 of lactation. This increase was associated with a decrease in plasma concentration of BCAA:Lys, suggesting a competitive mechanism between cationic and BCAA for transport of AA across mammary cells.

Sexual behavior of castrated boars treated with prostaglandin F(2alpha).

The objectives were to test the hypothesis that exogenous prostaglandin F(2alpha) (PGF(2alpha)) temporarily restores sexual behavior of castrated boars, and to evaluate effects of PGF(2alpha) on serum hormone concentrations. At 35 d after castration, nine lean-type adult boars were randomly assigned to three treatments in a 3x3 latin square (with three replicates). Treatments were three doses of PGF(2alpha) doses (0, 10, and 20mg) and three periods of treatment, with 5 d between each period. Serum testosterone (T) concentrations were non-detectable at the start of the experiment. Serum concentrations of estradiol (E2), LH, prolactin (PRL), and cortisol were unaffected (P>0.05) by PGF(2alpha) treatment. The interval from treatment to ejaculation in boars treated with 10mg (758s) or 20mg (660s) PGF(2alpha) did not differ, but were different (P < 0.05) from control boars (>1 800s). Ejaculation duration and false mounts differed (P < 0.05) between control boars and boars treated with 10 or 20mg PGF(2alpha). In conclusion, PGF(2alpha) treatment did not change serum concentrations of T, E2, LH, PRL, or cortisol, but restored sexual behavior. This restoration may have been due to an effect of PGF(2alpha) directly in specific areas of the brain, or indirectly via release of other hormones that stimulated areas in the brain that affected sexual behavior.

Immunohistochemical expression of somatostatin receptors in digestive endocrine tumours.

INTRODUCTION: Somatostatin receptors are expressed in a large number of human tumours. The somatostatin receptors types 1-5 expression in a series including 100 gastro-entero-pancreatic endocrine tumours were analysed. METHODS: From a prospectively built database of patients with gastro-entero-pancreatic endocrine tumours referred from three institutions, 100 cases with clinical and pathological data were selected. Somatostatin receptors expression by immunohistochemistry with somatostatin receptor types 1-5 antibodies in tissue paraffin sections were studied and correlated with the histological diagnosis according to the WHO classification, location and functional status. RESULTS: Of the 100 cases, 67 were gastrointestinal tumours, 25 pancreatic and 8 liver metastasis of unknown origin. Thirty-one of them were functioning tumours: 2 insulinomas, 5 gastrinomas, 1 glucagonoma and 23 carcinoids. Somatostatin receptors expression was observed in 94 tumours. The six negative cases were all non-functioning tumours. Somatostatin receptors 2a and 5 were highly expressed (86 and 62%, respectively), and surprisingly found even in poorly differentiated endocrine carcinomas. Somatostatin receptors expression was less frequent in pancreatic than in gastrointestinal tumours. Well-differentiated neoplasms had a higher density of somatostatin receptors. Only SSTR2a showed membrane staining. CONCLUSIONS: Immunohistochemistry revealed that somatostatin receptors were highly expressed in both primary and metastatic gastro-entero-pancreatic endocrine tumours with heterogeneous staining distribution. It proved to be a reliable technique even in small tumour samples.

Encefalopatía hepática: el manganeso también brilla en T1 / Hepatic encephalopathy: manganese also shines in T1

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