Sectional anatomic and tomographic study of the feline abdominal cavity for obtaining a three-dimensional vascular model

BACKGROUND

Unlike dogs, feline abdominal studies are rare. Note that anatomical estudies in felines are scarce and almost unique using feline cadaver by means of sectional anatomy and computed tomography (CT) or magnetic resonance imaging (MRI). Aims: In this study, a non-pathological vascularization model of feline abdomen was conducted on three adult cats was using anatomical and diagnostic imaging techniques.

METHODS

A live pet cat and two cat cadavers were used in this study. Cat cadavers were injected with colored latex to show well-differentiated vascular structures and serial sections of cat abdomen were then provided. Computed tomography was performed by injecting an iodinated contrast medium through the cephalic vein of a live cat immediately before scanning. The CT images showed the arterial and venous vascular formations hyper-attenuated with two tomographic windows. The correlation between anatomical sections and their CTs was studied to identify vascular and and visceral structures.

RESULTS

Hyper-attenuated vascular structures with the contrast medium were identified and marked along their path in the series of Dicom images with the Amira program. In this approach, sequentially and semiautomatically, vascular volumetric reconstruction was obtained without visceral formations. With the OsiriX program, volumetric reconstruction was automatic and maintained the fidelity of all visceral and vascular formations.

CONCLUSION

We conclude that these improved prototypes could be used in veterinary clinics as normal vascular models and as a basis for obtaining future 3D models of vascular anomalies such as portosystemic shunts.

Three-dimensional time of flight magnetic resonance angiography of the heart and associated vessels in a cat

The aim of this study was to describe the normal magnetic resonance angiography (MRA) of the heart and associated vessels in a mature female cat using a 1.5-Tesla magnet. Non-contrast enhanced MRA was performed using a three-dimensional time of flight (TOF) sequence in parasagittal and dorsal aspects. Relevant cardiac and vascular structures were labelled on three-dimensional Time of flight images. Time of flight imaging showed details of the heart cavities and vessels lumen due to the high signal intensity of fast-flowing blood compared with bones, muscles, and lungs, which appeared with low signal intensity. Three-dimensional TOF sequences provided adequate anatomical details of the heart and good differentiation of the vascular structures that could be used for interpretation of cardiac images and to assist in future MRA studies.

Note: Device for obtaining volumetric, three-component velocity fields inside cylindrical cavities

We describe a device designed and built to obtain the three-component, steady state velocity field in the whole volume occupied by a fluid in motion contained in a cavity with cylindrical walls. The prototype comprises a two-camera stereoscopic particle image velocimetry system mounted on a platform that rotates around the volume under analysis and a slip ring arrangement that transmits data from the rotating sensors to the data storage elements. Sample observations are presented for natural convection in a cylindrical container but other flows can be analyzed.

[Study of the expression of neural stem cell markers in neuroblastoma tumor samples and correlation with prognostic factors]

INTRODUCTION

The existence of cancer stem cells (CSC) in neuroblastoma (NB) has been associated with the development of metastasis, resistance to chemotherapy and recurrence. Our objective is to analyze the expression of proliferation and differentiation markers of neural progenitor cells in NB samples, and to correlate this expression with clinical variables such as histology, genetics and response to conventional therapy.

MATERIAL AND METHODS

We performed a retrospective-experimental study with neuroblastoma samples obtained from biopsies or tumor resections between 2010-2012 in our Hospital. Fluorescence immunohistochemistry was used to analyze the expression of the different markers: CD44, CD74, CD133, tyrosine hydroxylase, endothelin receptors type A (ETA) and B (ETB), p75, nestina y and Phox2b, all of them related to neural stem cell biology. The level of expression of the markers was then correlated with clinical variables.

RESULTS

Nestin expression was positive in 72.2% of samples and ETA in 66.7%. PHOX2B and CD74 expression were lower, being positive in less than 30%. The markers CD44, ETB and PHOX2B were expressed in more aggressive tumors. ETA expression correlated significantly with unfavorable histology tumors (p= 0.01), N-myc amplification (p= 0.05) and recurrence/progression (p= 0.05).

CONCLUSION

The expression of CD44, ETB and ETA was associated with more aggressive tumors and poor prognostic factors. These markers are in the membrane of neural stem cells and may be useful to identify and isolate by flow cytometry CSCs of NB for the study of new therapeutic targets.

Critical comparison between modified Monier-Williams and electrochemical methods to determine sulfite in aqueous solutions

In the present work, known concentration of sulfite aqueous solutions in the presence and absence of gallic acid was measured to corroborate the validity of modified Monier-Williams method. Free and bound-sulfite was estimated by differential pulse voltammetry. To our surprise, the modified Monier-Williams method (also known as aspiration method) showed to be very inaccurate for free-sulfite, although suitable for bound-sulfite determination. The differential pulse approach, using the standard addition method and a correction coefficient, proved to be swift, cheap, and very precise and accurate.

Genetic variants associated with severe pneumonia in A/H1N1 influenza infection

The A/H1N1 influenza strain isolated in Mexico in 2009 caused severe pulmonary illness in a small number of exposed individuals. Our objective was to determine the influence of genetic factors on their susceptibility. We carried out a case-control association study genotyping 91 patients with confirmed severe pneumonia from A/H1N1 infection and 98 exposed but asymptomatic household contacts, using the HumanCVD BeadChip (Illumina, San Diego, CA, USA). Four risk single-nucleotide polymorphisms were significantly (p<0.0001) associated with severe pneumonia: rs1801274 (Fc fragment of immunoglobulin G, low-affinity IIA, receptor (FCGR2A) gene, chromosome 1; OR 2.68, 95% CI 1.69-4.25); rs9856661 (gene unknown, chromosome 3; OR 2.62, 95% CI 1.64-4.18); rs8070740 (RPA interacting protein (RPAIN) gene, chromosome 17; OR 2.67, 95% CI 1.63-4.39); and rs3786054 (complement component 1, q subcomponent binding protein (C1QBP) gene, chromosome 17; OR 3.13, 95% CI 1.89-5.17). All SNP associations remained significant after adjustment for sex and comorbidities. The SNPs on chromosome 17 were in linkage disequilibrium. These findings revealed that gene polymorphisms located in chromosomes 1 and 17 might influence susceptibility to development of severe pneumonia in A/H1N1 infection. Two of these SNPs are mapped within genes (FCGR2A, C1QBP) involved in the handling of immune complexes and complement activation, respectively, suggesting that these genes may confer risk due to increased activation of host immunity.

Cyclooxygenase-2 expression is related with localization, proliferation, and overall survival in canine melanocytic neoplasms

A direct relationship has been firmly established between cyclooxygenase-2 (COX-2) expression and malignant behavior in human melanoma. This report examines the relationship between COX-2 expression and tumor location, mitotic and proliferative indices, degree of T CD3(+) lymphocyte infiltration, overall survival, and frequency of recurrence and metastasis of 57 melanocytic tumors (25 oral and 32 cutaneous). COX-2 was highly or moderately expressed in 88% of oral neoplasms (22 of 25), whereas for their cutaneous counterparts, COX-2 expression was low or insignificant in 75% of cases (24 of 32). High and moderate COX-2 expression levels were observed in 73% of melanocytic tumors with a mitotic index ≥ 3 per 10 high-power fields (26 of 36), whereas in 81% of tumors with a mitotic index < 3 (17 of 21), expression was mild or absent. There were 41 cases with known clinical outcomes; of those showing high, moderate, and mild COX-2 expression, 83.3% (10 of 12), 37.5% (3 of 8), and 25% (2 of 8) died, respectively, whereas 100% of animals showing no COX-2 expression (13 of 13) were still alive at the last follow-up. COX-2 expression was statistically correlated with tumor location, mitotic and percentage Ki-67 proliferative indices, and overall survival, frequency of neoplastic recurrence and metastasis. Regression analysis also showed disease-specific predictive value for COX-2 expression for subjects with melanocytic neoplasms. Additionally, only high COX-2 expression showed significant differences in overall survival, in comparison with moderate, mild, or absent expression. These results suggest that high COX-2 expression may be considered a prognostic biomarker and potentially as a target for therapeutic and preventive strategies in canine melanocytic neoplasms.

Bacteriological characterization of wastewater samples obtained from a primary treatment system on a small scale swine farm

This study was carried out in order to quantify enteric bacteria and identify the presence of Salmonella spp., Escherichiacoli, Clostridiumperfringens and Erysipelothixrhusiopathiae in the liquid fraction of excreta generated from a small scale swine farm by means of a primary treatment system, consisting of the separation of solids and the sedimentation of liquids. Samples were collected at the following stages of the treatment: collection basin (CB), liquid obtained from a solids separator (SLF) and liquid from the sedimentation basin (SB). In each sample, enteric bacteria (cfu/g wet weight) and E. coli were quantified, Salmonella spp. was isolated and typified, and C. perfringens, and E. rhusiopathiae were isolated. No significant differences (p>0.05) were found in the enteric bacteria and E. coli population levels at any treatment stage. S.choleraesuis was found in 20% of CB samples analyzed, 40% of SLF samples and 30% of SB samples. C. perfringens was isolated from SLF and SB. E. rhusiopathiae was not isolated (below the minimum detection limit). Results suggest that primary treatment does not reduce the amount of enteric bacteria, or eliminate Salmonella spp., E. coli and C. perfringens. Therefore, it is necessary to apply additional treatments to allow safe use of the liquid obtained in the farm.

Antidiabetic activities of Tecoma stans (L.) Juss. ex Kunth

ETHNOPHARMACOLOGICAL RELEVANCE

Tecoma stans aqueous extract (TAE) is widely used as a traditional antidiabetic remedy in Mexico; its rational use is controversial. We provide evidence of its main antidiabetic activities.

AIM OF THE STUDY

To evaluate in vivo and in vitro intestinal alpha-glucosidases inhibition as the possible mode of action of TAE on type 2 diabetes mellitus (DM2) animal models, and to test the effects of its sub-chronic administration on lipids and glucose blood levels.

MATERIALS AND METHODS

In healthy and streptozotocin (STZ)-induced diabetic male Sprague-Dawley rats, glucose or cornstarch was administered after an oral dose of TAE, acarbose, tolbutamide or vehicle, in order to build starch and glucose tolerance curves (STC and GTC). An intestinal brush border preparation was used to evaluate the TAE alpha-glucosidases inhibitory activity. Moreover, in STZ-induced diabetic rats TAE, tolbutamide or vehicle was administered for 21 days for evaluate their effects on fasting glucose cholesterol and triglycerides. Also, TAE total phenolic compounds were quantified.

RESULTS

In STC, TAE decreased hyperglycemic peak values in both healthy and STZ-treated rats, in a magnitude similar to that of acarbose. The in vitro preparation showed a dose-dependent inhibition of glucose release from starch. Sub-chronic administration of TAE significantly reduced cholesterol and triglycerides levels. Moreover, we confirmed that acute and sub-chronic administration of TAE (500mg/kg) in both rat models did not diminish fasting glucose and did not modify the GTC.

CONCLUSIONS

The study present evidence that the main antidiabetic effect of TAE is due to intestinal alpha-glucosidase inhibition by decreasing the postprandial hyper-glycaemia peak; in addition, TAE sub-chronic administration reduces triglycerides and cholesterol, without modifying fasting glucose.

FLUORESCENT BERBERINE BINDING AS A MARKER OF INTERNAL GLYCOSAMINOGLYCANS SULFATE IN BOVINE OOCYTES AND SPERM CELLS

The use of berberine as a biological marker of glycosamineglycans sulfate was employed to corroborate the presence of heparin in mammalian oocytes and sperm and its distribution in all the structures, or only in some specialized zones, of the male and female gametes. Oocytes and sperms were treated with 1.8 mM berberine for the presence of heparin and examined 10, 30, 60, and 120 minutes later. We have found that heparin is homogeneously distributed in all the zones of bovine oocytes and in sperm cells. When sperm cells are first treated with 80 microM of heparin and then berberine, 40% of them display in their post acrosomal region an intense yellow fluorescence. This may be in relation to the high amount of heparin binding sites due to the presence of the reticular membranous like system in this sperm region and in its possible role whereby gametes recognize and adhere to one another. Therefore, the use of berberine as a fluorescent marker of heparin represents clear proof of the presence of GAGs and their binding sites in the outside and inside of mammalian gametes, reinforcing the importance they play in the events of the process of fertilization.

Structural organization of Bacillus subtilis phage phi29. A model

Phage phi29 is a nonisometric virus producing several types of morphological variants in normal infections. The study of these variants by electron microscopy, and their comparison with those from T-even phages, suggest that the capsid of phage phi29 is a prolate icosahedron. Phage phi29 capsid consists of a major protein, p8, and an additional protein, p8.5, making up the fibers. We have determined the number of subunits of each structural protein per viral particle taking into account the phage molecular weight (between 28 and 29.6 x 10(6)), the molecular weight of each structural protein, and the mass percentage of each protein with respect to the total protein mass of the phage. These values, together with the results obtained from chemical crosslinking of the structural proteins on the phage, suggest that the capsid contains protein p8 dimers clustered in trimers.

A quantitative trait locus genome scan for porcine muscle fiber traits reveals overdominance and epistasis

Muscle histochemical characteristics are decisive determinants of meat quality. The relative percentage and diameters of the different muscular fiber types influence crucial aspects of meat such as color, tenderness, and ultimate pH. Despite its relevance, however, the information on muscle fiber genetic architecture is scant, because histochemical muscle characterization is a laborious task. Here we report a complete QTL scan of muscle fiber traits in 160 animals from a F(2) cross between Iberian and Landrace pigs using 139 markers. We identified 20 genome regions distributed along 15 porcine chromosomes (SSC1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and X) with direct and(or) epistatic effects. Epistasis was frequent and some interactions were highly significant. Chromosomes 10 and 11 seemed to behave as hubs; they harbored 2 individual QTL, but also 6 epistatic regions. Numerous individual QTL effects had cryptic alleles, with opposite effects to phenotypic pure breed differences. Many of the QTL identified here coincided with previous reports for these traits in the literature, and there was overlapping with potential candidate genes and previously reported meat quality QTL.

Computed Tomography (CT) of the Lungs of the Dog Using a Helical CT Scanner, Intravenous Iodine Contrast Medium and Different CT Windows

The aim of this study was to determine the accuracy of helical computed tomography (CT) for visualizing pulmonary parenchyma and associated formations in normal dogs. CT scan was performed by using intravenous contrast medium and by applying different types of CT windows: soft tissue and lung windows, and high-resolution computed tomography of the lung. This technique allowed, especially with lung window types, a good view of the parenchyma, bronchial tree, vascular structures and pleural cavity. The selected images, with high anatomical quality and tissue contrast, may be a reference for future clinical studies of this organ. Thus, helical CT is a promising non-invasive method of diagnosing a wide variety of pulmonary diseases in dogs.

Generation of basis sets with high degree of fulfillment of the Hellmann-Feynman theorem

A direct relationship is established between the degree of fulfillment of the Hellman-Feynman (electrostatic) theorem, measured as the difference between energy derivatives and electrostatic forces, and the stability of the basis set, measured from the indices that characterize the distance of the space generated by the basis functions to the space of their derivatives with respect to the nuclear coordinates. On the basis of this relationship, a criterion for obtaining basis sets of moderate size with a high degree of fulfillment of the theorem is proposed. As an illustrative application, previously reported Slater basis sets are extended by using this criterion. The resulting augmented basis sets are tested on several molecules finding that the differences between energy gradient and electrostatic forces are reduced by at least one order of magnitude.

Normal Anatomical Imaging of the Thorax in Three Dogs: Computed Tomography and Macroscopic Cross Sections with Vascular Injection

The purpose of this study was to provide a new reference for interpretation of the normal anatomy of the canine thorax as imaged using computed tomography (CT). Three mature dogs, all mixed breed males, were used for this study. The dogs were sedated, anaesthetized and maintained in sternal recumbency. CT study from the first to the thirteen thoracic vertebra was performed with a TOSHIBA 600 HQ scanner (third generation equipment). Dogs were killed and vascular-injection technique was performed: red latex and blue latex filled vascular system. Injected dogs were frozen and sectioned with an electric bandsaw, the cuts matched as closely as possible to the CT images. The CT images from this study are intended as a reference for clinical CT imaging studies of the thoracic cavity of the dog and for interpreting lesions of the thorax and associated structures.

Translation of STO charge distributions

Barnett and Coulson's zeta-function method (M. P. Barnett and C. A. Coulson, Philos. Trans. R. Soc., Lond. A 1951, 243, 221) is one of the main sources of algorithms for the solution of multicenter integrals with Slater-type orbitals. This method is extended here from single functions to two-center charge distributions, which are expanded at a third center in terms of spherical harmonics times analytical radial factors. For s-s distributions, the radial factors are given by a series of factors corresponding to the translation of s-type orbitals. For distributions with higher quantum numbers, they are obtained from those of the s-s distributions by recurrence. After analyzing the convergence of the series, a computational algorithm is proposed and its practical efficiency is tested in three-center (AB/CC) repulsion integrals. In cases of large basis sets, the procedure yields about 12 correct significant figures with a computational cost of a few microseconds per integral.

Utility of point-of-care haemoglobin measurement in the HemoCue-B haemoglobin for the initial diagnosis of anaemia

Measurement of haemoglobin (Hb) concentration provides a reliable indication of the presence and severity of anaemia. However, other laboratory parameters are usually requested as well, leading to an increase in socio-sanitary costs. Accordingly, this study was undertaken to ascertain the reliability of point-of-care Hb determination with the portable photometer HemoCue-B haemoglobin (HBH) and to evaluate its utility for the initial diagnosis of anaemia. Hb was measured (x3) in 20 venous blood samples diluted with saline (v/v; 1 : 0, 2 : 1, 1 : 1, 2 : 1 and 3 : 1) to obtain a wide range of Hb and in venous and capillary blood samples from 247 primary health care patients. All HBH results were compared with those yielded by the reference cell counter Pentra 120 Retic (ABX). In diluted samples, Hb values obtained with either method were not significantly different (ABX-HBH, -0.01 +/- 0.32 g/dl; 95% CI, -0.04 to 0.028 g/dl) and showed an excellent Pearson's coefficient of correlation (r = 0.992; P < 0.01). HBH provides accurate values if at least 4 mul of blood is loaded into the cuvette. There were no significant differences between Hb measured in venous (v) and capillary (c) blood samples in primary care patients. Eighteen anaemic patients were detected by ABX measurements (7.3%; 15 female/3 male), 18 by HBHv (specificity, 100%; sensitivity, 100%) and 25 by HBHc (eight false positives; one false negative; specificity, 94.4%; sensitivity, 96.5%). Compared with ABX, HBH provides accurate and precise measurements for a wide range of Hb and its use in primary health care seems to be a good method for the initial diagnosis of anaemia.

Iron metabolism, inflammation and anemia in critically ill patients. A cross-sectional study

INTRODUCTION

For critically patients, enteral immunonutrition results in notable reductions in infections and in length of stay in hospital, but not on mortality, raising the question as to whether this relate to the heterogeneous nature of critically ill patients or to the absence of the altered absorption of specific nutrients within the immunonutrient mix (e.g. iron). Immune-associated functional iron deficiency (FID) is not only one of the many causes or anaemia in the critically ill, but also a cause of inappropriate immune response, leading to a longer duration of episodes of systemic inflammatory response syndrome and poor outcome.

OBJECTIVE

This prospective cross-sectional study was undertaken to assess the prevalence of FID in critically ill patients during their stay in intensive care (ICU) in order to find the more appropriate population of patients that can benefit from iron therapy.

METHOD

Full blood cell counts, including reticulocytes (RETIC), serum iron (SI), transferring levels (TRF) and saturation (satTRF), serum TFR receptor (sTfR), ferritin (FRT) and C-reactive protein (CRP) were measured in venous blood samples from 131 random patients admitted to the ICU for at least 24 h (Length of ICU stay, LIS; min: 1 day; max: 38 days).

RESULTS

Anaemia (Hb < 12 g/dL) was present in 76% of the patients (Hb < 10 g/dL in 33%), hypoferremia (SI < 45 microg/dl) in 69%; satTRF < 20% in 53%; FRT < 100 ng/mL in 23%; sTfR > 2.3 mg/dL in 13%; and CRP > 0.5 mg/dL in 88%. Statistically significant correlations (r of Pearson; *p < 0.05, **p < 0.01) were obtained for serum CRP levels and WBC**, Hb*, TRF**, satTRF*, and FRT**. There was also a strong correlation between TRF and FRT (-0.650**), but not between FRT and satTRF or SI. LIS correlated with Hb*, CRP**, TRF*, satTRF* and FRT**.

CONCLUSIONS

A large proportion of critically ill patients admitted to the ICU presented the typical functional iron deficiency (FID) of acute inflammation-related anaemia (AIRA). This FID correlates with the inflammatory status and the length of stay at the ICU. However, 21% of the ICU patients with AIRA had an associated real iron deficiency (satTRF < 20; FRT < 100 and sTfR > 2.3). Since oral supplementation of iron seems to be ineffective, all these patients might benefit of iv iron therapy for correction of real or functional iron deficiency, which in turn might help to ameliorate their inflammatory status.

Isolation of Salmonella spp. from liquid and solid excreta prior to and following ensilage in ten swine farms located in central Mexico

A study was carried out to define selected bacteriological characteristics of residues from 10 swine farms, 5 with or without prior clinical enteric disease (PCED) and to determine the effect of ensilage on the bacteria present in the solid fraction. At each farm, samples were taken from the sedimentation basin (SB), the solid fraction (SF), and the liquid fraction (LF). For each sample, CFU/g for enteric bacteria were quantified; Salmonella spp. were isolated and typified. Solid phase samples from each farm were used to prepare the ensilage, with a mixture of solids (80%), sorghum (12%) and molasses (8%). The quantity of enteric bacteria was significantly greater in farms without PCED (P < 0.05). Salmonella enterica were isolated from 8/10 of the farms with and without PCED; in 8 from SB; in 6 from LF; and in 5 from SF. Enteric bacteria were not isolated from silage, therefore, ensilage may be an alternative treatment for excreta that allows the elimination of pathogens such as Salmonella spp.

Anatomy of the Cranioencephalic Structures of the Camel (Camelus dromedarius L.) by Imaging Techniques: A Magnetic Resonance Imaging Study

The objective of this study was to define the anatomy of the cranioencephalic structures and associated formations in camel using magnetic resonance imaging (MRI). MR images were acquired in sagittal, transverse and oblique dorsal planes, using spin-echo techniques, a magnet of 1.5 T and a standard human body coil. MR images were compared with corresponding frozen cross-sections of the head. Different anatomic structures were identified and labelled at each level. The resulting images provided excellent soft tissue contrast and anatomic detail of the brain and associated structures of the camel head. Annotated MR images from this study are intended to be a reference for clinical imaging studies of the head of the dromedary camel.

Efficiency of the algorithms for the calculation of Slater molecular integrals in polyatomic molecules

The performances of the algorithms employed in a previously reported program for the calculation of integrals with Slater-type orbitals are examined. The integrals are classified in types and the efficiency (in terms of the ratio accuracy/cost) of the algorithm selected for each type is analyzed. These algorithms yield all the one- and two-center integrals (both one- and two-electron) with an accuracy of at least 12 decimal places and an average computational time of very few microseconds per integral. The algorithms for three- and four-center electron repulsion integrals, based on the discrete Gauss transform, have a computational cost that depends on the local symmetry of the molecule and the accuracy of the integrals, standard efficiency being in the range of eight decimal places in hundreds of microseconds.

Histochemical Skeletal Muscle Fibre Types in the Sheep

In this study, the differentiation of adult and postnatal muscle fibres in sheep longissimus thoracis muscle has been characterized. By using a variety of histochemical methods, we have investigated the m-ATPase and metabolic activities of skeletal muscle fibres in adult sheep and lambs aged between 1 day and 3 months. Types I, IIA, IIB and IIC fibres were identified. The results showed that the interpretation of the fibre type composition depends on the methods used. The findings also revealed that the fibre types IIA and IIB can be separated histochemically in sheep by using the correct m-ATPase technique, even at early stages of postnatal development, and that the origin of the four different fibres of the adult can be traced back to early postnatal stages.

Electrostatic potentials and fields from density expansions of deformed atoms in molecules

The exact representation of the molecular density by means of atomic expansions, consisting in spherical harmonics times analytical radial factors, is employed for the calculation of electrostatic potentials, fields, and forces. The resulting procedure is equivalent to an atomic multipolar expansion in the long-range regions, but works with similar efficiency and accuracy in the short-range region, where multipolar expansions are not valid. The performances of this procedure are tested on the calculation of the electrostatic potential contour maps and electrostatic field flux lines of water and nitrobenzene, computed from high-quality molecular electron densities obtained with Slater basis sets.

Analytical method for the representation of atoms-in-molecules densities

We present analytic refinements and applications of the deformed atomic densities method [Fernández Rico, J.; López, R.; Ramírez, G. J Chem Phys 1999, 110, 4213-4220]. In this method the molecular electron density is partitioned into atomic contributions, using a minimal deformation criterion for every two-center distributions, and the atomic contributions are expanded in spherical harmonics times radial factors. Recurrence relations are introduced for the partition of the two-center distributions, and the final radial factors are expressed in terms of exponential functions multiplied by polynomials. Algorithms for the practical implementation are developed and tested, showing excellent performances. The usefulness of the present approach is illustrated by examining its ability to describe the deformation of atoms in different molecular environments and the relationship between these atomic densities and some chemical properties of molecules.

Intraperitoneal application of bupivacaine plus morphine for pain relief after laparoscopic cholecystectomy

BACKGROUND AND OBJECTIVE

Intraperitoneal administration of a local anaesthetic in combination with an opioid, for the relief of postoperative pain, has already been reported except after laparoscopic cholecystectomy. This study was aimed at assessing the analgesic effect of the intraperitoneal administration of bupivacaine and morphine in patients undergoing laparoscopic cholecystectomy.

METHODS

At the end of laparoscopic cholecystectomy, in a double-blind, randomized manner, one of the following injections was given intraperitoneally. There were 30 patients in each group: Group 1, physiological saline 30 mL; Group 2, bupivacaine 0.25% 30 mL; Group 3, bupivacaine 0.25% 30 mL plus morphine 2 mg. In addition, Group 2 received 2 mg intravenous (i.v.) morphine in 2 mL saline, and Groups 1 and 3, 2 mL saline intravenously. Patients' postoperative pain was evaluated using a visual analogue scale and a verbal rating score. The postoperative analgesic requirement was assessed by the total dose of metamizol administered by an i.v. patient-controlled analgesia (PCA) device. Pain, vital signs, supplemental analgesic consumption and side-effects were recorded for all patients for 24 h.

RESULTS

There were no differences between the three groups regarding pain scores (at rest and coughing) during the study except in the first 2 h, when scores were lower for patients receiving intraperitoneal bupivacaine plus i.v. morphine (P < 0.05). Supplemental consumption of metamizol was significantly lower (P < 0.05) in Group 3 than in Group 1 during the first 6 h after surgery. However, the cumulative doses of metamizol were also lower in Group 2 than in Groups 1 and 3 over the entire study (2025 +/- 1044 mg vs. 4925 +/- 1238 and 4125 +/- 1276mg; P < 0.05).

CONCLUSIONS

In patients undergoing laparoscopic cholecystectomy, the intraperitoneal administration of morphine plus bupivacaine 0.25% reduced the analgesic requirements during the first 6 postoperative hours compared with the control group. However, the combination of intraperitoneal bupivacaine 0.25% and i.v. morphine was more effective for treatment of pain after laparoscopic cholecystectomy.

Polarized basis sets of Slater-type orbitals: H to Ne atoms

We present three Slater-type atomic orbital (STO) valence basis (VB) sets for the first and second row atoms, referred to as the VB1, VB2, and VB3 bases. The smallest VB1 basis has the following structure: [3, 1] for the H and He atoms, [5, 1] for Li and Be, and [5, 3, 1] for the B to Ne series. For the VB2 and VB3 bases, both the number of shells and the number of functions per shell are successively increased by one with respect to VB1. With the exception of the H and Li atoms, the exponents for the VB1 bases were obtained by minimizing the sum of the Hartree-Fock (HF) and frozen-core singles and doubles configuration interaction (CISD FC) energies of the respective atoms in their ground state. For H and Li, we minimized the sum of the HF and CISD FC energies of the corresponding diatoms (i.e., of H(2) or Li(2)) plus the ground-state energy of the atom. In the case of the VB2 basis sets, the sum that was minimized also included the energies of the positive and negative ions, and for the VB3 bases, the energies of a few lowest lying excited states of the atom. To account for the core correlations, the VBx (x = 1, 2, and 3) basis sets for the Li to Ne series were enlarged by one function per shell. The exponents of these extended (core-valence, CV) basis sets, referred to, respectively, as the CVBx (x = 1, 2, and 3) bases, were optimized by relying on the same criteria as in the case of the VBx (x = 1, 2, and 3) bases, except that the full CISD rather than CISD FC energies were employed. We show that these polarized STO basis sets provide good HF and CI energies for the ground and excited states of the atoms considered, as well as for the corresponding ions.

Interventions for the treatment and management of chronic fatigue syndrome: a systematic review

CONTEXT

A variety of interventions have been used in the treatment and management of chronic fatigue syndrome (CFS). Currently, debate exists among health care professionals and patients about appropriate strategies for management.

OBJECTIVE

To assess the effectiveness of all interventions that have been evaluated for use in the treatment or management of CFS in adults or children.

DATA SOURCES

Nineteen specialist databases were searched from inception to either January or July 2000 for published or unpublished studies in any language. The search was updated through October 2000 using PubMed. Other sources included scanning citations, Internet searching, contacting experts, and online requests for articles.

STUDY SELECTION

Controlled trials (randomized or nonrandomized) that evaluated interventions in patients diagnosed as having CFS according to any criteria were included. Study inclusion was assessed independently by 2 reviewers. Of 350 studies initially identified, 44 met inclusion criteria, including 36 randomized controlled trials and 8 controlled trials.

DATA EXTRACTION

Data extraction was conducted by 1 reviewer and checked by a second. Validity assessment was carried out by 2 reviewers with disagreements resolved by consensus. A qualitative synthesis was carried out and studies were grouped according to type of intervention and outcomes assessed.

DATA SYNTHESIS

The number of participants included in each trial ranged from 12 to 326, with a total of 2801 participants included in the 44 trials combined. Across the studies, 38 different outcomes were evaluated using about 130 different scales or types of measurement. Studies were grouped into 6 different categories. In the behavioral category, graded exercise therapy and cognitive behavioral therapy showed positive results and also scored highly on the validity assessment. In the immunological category, both immunoglobulin and hydrocortisone showed some limited effects but, overall, the evidence was inconclusive. There was insufficient evidence about effectiveness in the other 4 categories (pharmacological, supplements, complementary/alternative, and other interventions).

CONCLUSIONS

Overall, the interventions demonstrated mixed results in terms of effectiveness. All conclusions about effectiveness should be considered together with the methodological inadequacies of the studies. Interventions which have shown promising results include cognitive behavioral therapy and graded exercise therapy. Further research into these and other treatments is required using standardized outcome measures.

Effect of orally administered guanosine on seizures and death induced by glutamatergic agents

Intraperitoneal guanosine has been shown to prevent quinolinic acid-induced seizures in mice. In this study, we investigated the effect of orally administered guanosine on seizures induced by the glutamate agonists quinolinic acid and kainate, and the endogenous glutamate releaser alpha-dendrotoxin. Guanosine (7.5 mg/kg, per os), administered 75 min in advance, prevented 70% of seizures induced by i.c.v. quinolinic acid, being as efficient as the NMDA channel blocker MK-801 administered intraperitoneally. Guanosine was ineffective against kainate-induced seizures, but significantly reversed the potentiation of seizures and death caused by the concomitant injection of MK-801. Guanosine also significantly prevented seizures and death induced by i.c.v. alpha-dendrotoxin, whereas MK-801 and phenobarbital only prevented death. Altogether, our findings underscore the therapeutic potential of oral administration of guanosine for treating diseases involving glutamatergic excitotoxicity, including epilepsy.

Immobilized amyloid precursor protein constructs: a tool for the in vitro screening of glial cell reactivity

Astrocytes and microglia are closely associated with amyloid plaques in Alzheimer's disease (AD). Microglia constitute the first barrier surrounding plaques, although they seem to be unable to remove them efficiently. We evaluated the reaction of microglial cells from neonatal rats and mice to plaque mimetics. The C-terminal part of the amyloid precursor protein (APP) or amyloid peptide (A beta) was immobilized to either 60-microm or 2.8-microm beads and incubated with microglial cells. Beads of 60 microm, having approximately the size of senile plaques, were not phagocytosed, in contrast to 2.8-microm beads, which were phagocytosed by microglia but not by astrocytes. Once taken up by the cells, proteins immobilized to the beads were degraded rapidly, as confirmed by mass spectrometry and immunofluorescence with an antibody against beta-amyloid. On the other hand, no protein degradation was observed with 60-microm beads. Also, probably as a reaction to its incapability to phagocytose the beads, glia organized around the beads and started to proliferate. Cell proliferation was more pronounced when the beads contained the A beta epitope compared with the beads with an inert surface. This in vitro effect could be exploited to set up a screening assay for compounds that ameliorate the adverse reaction of microglia supposed to contribute to the pathogenesis of AD.

Molecular dynamics simulations of the conformational changes of the glutamate receptor ligand-binding core in the presence of glutamate and kainate

Excitatory synaptic transmission is mediated by ionotropic glutamate receptors (iGluRs) through the induced transient opening of transmembrane ion channels. The three-dimensional structure of the extracellular ligand-binding core of iGluRs shares the overall features of bacterial periplasmic binding proteins (PBPs). In both families of proteins, the ligand-binding site is arranged in two domains separated by a cleft and connected by two peptide stretches. PBPs undergo a typical hinge motion of the two domains associated with ligand binding that leads to a conformational change from an open to a closed form. The common architecture suggests a similar closing mechanism in the ligand-binding core of iGluRs induced by the binding of specific agonists. Starting from the experimentally determined kainate-bound closed form of the S1S2 GluR2 construct, we have studied by means of molecular dynamics simulations the opening motion of the ligand-binding core in the presence and in the absence of both glutamate and kainate. Our results suggest that the opening/closing interdomain hinge motions are coupled to conformational changes in the insertion region of the transmembrane segments. These changes are triggered by the interaction of the agonists with the essential Glu 209 residue. A plausible mechanism for the coupling of agonist binding to channel gating is discussed.

Melatonin activates PKC-alpha but not PKC-epsilon in N1E-115 cells

Previous reports have revealed that calmodulin antagonism by melatonin is followed by microtubule enlargements and neurite outgrowths in neuroblastoma N1E-115 cells. In addition, activation of protein kinase C (PKC) by this neurohormone is also followed by increased vimentin phosphorylation, and reorganization of vimentin intermediate filaments (IFs) in N1E-115 cells. In this work, we further characterize the activation of PKC by melatonin in neuroblastoma N1E-115 cells. We studied the Ca(2+)-dependent effects of melatonin on PKC activity and distribution of PKC-alpha in isolated N1E-115 cell IFs. Also, the effects of melatonin on PKC-alpha translocation in comparison to PKC-epsilon, were studied in intact N1E-115 cells. The results showed that both melatonin and the PKC agonist phorbol-12-myristate-13-acetate increased PKC activity in isolated IFs. The effects of the hormone were Ca(2+)-dependent, while those caused by the phorbol ester were produced with or without Ca(2+). Also, in isolated in situ IFs, the hormone changed the distribution of PKC-alpha. In intact N1E-115 cells, melatonin elicited PKC-alpha translocation and no changes were detected in PKC-epsilon. Phorbol-12-myristate-13-acetate modified the subcellular distribution of both PKC isoforms. The results showed that melatonin selectively activates the Ca(2+)-dependent alpha isoform of PKC and suggest that PKC-alpha activation by melatonin underlies IF rearrangements and participates in neurite formation in N1E-115 cells.