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Dissimilar aluminum alloys are preferred to fabricate structural parts for naval ships, combat, and armored personnel carrier vehicles. Attaining better mechanical and ballistic behavior of dissimilar aluminum alloy joints is very difficult with conventional welding techniques. One of the most promising solid-state techniques for joining different aluminum alloys is friction stir welding (FSW). The current work aims to evaluate the mechanical and ballistic behavior of dissimilar 5083 and 6063 aluminum plates joined by the FSW process. Defect-free dissimilar FSW joint was obtained for the range of tool rotation speed (800–1200 rpm) and welding speed (30–50 mm/min). The highest tensile and impact strength of dissimilar joints was obtained for tool rotation speed (1000 rpm) and welding speed (50 mm/min). The fine crystalline size was noticed in the stir zone (SZ) region compared to the remaining regions. Microstructure and microhardness were studied in the different regions of dissimilar joints. The stirring action of the tool causes a fine layer in the SZ region and results in higher hardness compared to other regions. The heat-affected zone (HAZ) of the retreating side (RS) exhibited the lowest hardness. The ballistic behavior of base materials and dissimilar FSW joints was estimated by striking a 7.62 mm projectile. The ballistic resistance of dissimilar FSW joints was slightly lower than the AA5083 and higher than the AA6063. Fractured surfaces of tensile and impact specimens resulted in ductile failure. The ballistic fracture studies of dissimilar FSW joints confirm that shear stress completely dominated failure.

El ictus es la complicación neurológica más frecuente tras una coronariografía. Nuestro objetivo fue estudiar las diferencias clínicas y pronósticas entre los códigos ictus (CI) poscateterismo y el resto de CI intra y extrahospitalarios.

Ischemic stroke is the most common neurological complication of cardiac catheterization resulting in a high morbidity and mortality. We present a 44-year-old man admitted for vasospastic angina that suffered a right middle cerebral artery (MCA) occlusion after a cardiac catheterization. Mechanical thrombectomy was indicated and complete arterial recanalization was achieved. The material obtained showed a fragment of a healthy artery. Partial radial endarterectomy and cerebral embolization may be a rare complication of cardiac catheterization.

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Antecedentes y objetivo: Los niveles elevados de vitamina B12 se han asociado a enfermedades oncohematológicas. Sin embargo, se desconoce la relevancia de su detección incidental en sujetos sin un diagnóstico previo de cáncer. Evaluar la relación de la hipercobalaminemia y el diagnóstico de un proceso tumoral y establecer los factores de riesgo.

La disección de arterias cervicales (DAC) es la causa del 2-3% de ictus isquémicos y del 10-25% en pacientes jóvenes. Nuestro objetivo es evaluar si la implementación de un centro terciario de ictus (CTI) facilita el diagnóstico y modifica el pronóstico de los pacientes con ictus agudo por DAC.

Background:Growth factors (GF) such as vascular endothelial growth factor (VEGF), angiopoietin‐1 (Ang‐1) and granulocyte‐colony stimulating factor (G‐CSF) have been associated with greater efficacy of tissue plasminogen activator (tPA) in experimental studies. Objectives:To study the association of these GF with arterial recanalization and clinical outcome in patients with acute ischemic stroke treated with tPA. Methods:We prospectively studied 79 patients with ischemic stroke attributable to MCA occlusion treated with i.v. tPA within the first 3 h from onset of symptoms. Continuous transcranial color‐coded sonography (TCCS) was performed during the first 2 h after tPA bolus to assess early MCA recanalization. Hemorrhagic transformation (HT) was classified according to ECASS II definitions. Good functional outcome was defined as a Rankin scale score of 0–2 at 90 days. GF levels were determined by ELISA. Results:Mean serum levels of VEGF, G‐CSF and Ang‐1 at baseline were significantly higher in patients with early MCA recanalization (n = 30) (all P < 0.0001). In the multivariate analysis, serum levels of VEGF (OR, 1.03), G‐CSF (OR, 1.02) and Ang‐1 (OR, 1.07) were independently associated with early MCA recanalization (all P < 0.0001). On the other hand, patients with parenchymal hematoma (PH) (n = 20) showed higher levels of Ang‐1 (P < 0.0001). Ang‐1 (OR, 1.12; P < 0.0001) was independently associated with PH, whereas patients with good outcome (n = 38) had higher levels of G‐CSF (P < 0.0001). G‐CSF was independently associated with good outcome (OR, 1.12; P = 0.036). Conclusions:These findings suggest that GF may enhance arterial recanalization in patients with ischemic stroke treated with t‐PA, although they might increase the HT.

Nanocrystallization kinetics is analyzed in the frame of instantaneous growth approximation, which implies that the time required for a crystallite to reach its final size is negligible with respect to the time required for the nanocrystallization process. This approach strongly simplifies the kinetic analysis and allows us to obtain the nucleation rate from both isothermal and nonisothermal nanocrystallization processes. Moreover, as no constraining mechanism is considered but the absence of growth, the results could be discussed in the frame of Johnson–Mehl–Avrami–Kolmogorov theory with a growth index equal to zero. Cellular automata simulations are in agreement with the observed kinetics and microstructure.

The metabolic syndrome (MetS) is a cluster of vascular risk factors associated with a prothrombotic state. We aimed to evaluate the impact of MetS on the response to systemic tPA treatment in patients with acute middle cerebral artery (MCA) ischemic stroke.

In our metropolitan area, the Stroke Code (SC) system allows immediate transfer of patients with acute stroke to a stroke center. It may be activated by community hospitals (A), emergency medical services (EMS, B), or the emergency department of the stroke center (C). Our aim was to analyze whether the SC activation source influences the access to thrombolytic therapy and outcome of patients with ischemic stroke.

Background: Capsule endoscopy has involved a significant advance in techniques for imaging of the small bowel. Its most frequent indication is for studying patients with obscure gastrointestinal bleeding (OGIB). Small bowel tumors are infrequent, representing only 1% to 3% of all malignant gastrointestinal tumors. This study aimed to assess retrospectively the occurrence and characteristics of tumoral pathology diagnosed by means of capsule endoscopy in patients with OGIB. Methods: A retrospective review analyzed the first 320 patients submitted to capsule endoscopy because of OGIB (166 with obscure overt bleeding and 154 with obscure occult bleeding) at a single center. The patients with a tumor diagnosis were analyzed in terms of incidence, characteristics, and treatment of OGIB pathology. Results: Tumor incidence was of 7.18% (23/320), with 65.2% of the cases supported with histologic confirmation (15/23). Obscure overt bleeding was the most frequent form of presentation, with the jejunum as the most frequent location (65.2%). For 16 patients, an intervention was conducted with a healing intent. Capsule endoscopy allowed the diagnosis of two cecal adenocarcinomas missed by colonoscopy. Conclusions: Small bowel tumors are not an infrequent cause of OGIB. Capsule endoscopy, even if it does not allow determination of the benign or malignant nature or the histologic type of the tumor, is a useful tool for the diagnosis and early management of these tumors.

Hemorrhagic transformation (HT) after cerebral ischemia seems to be related to the endothelial disruption secondary to the ischemic process. Albuminuria has recently been found to be a marker of chronic endothelial damage.

A versatile procedure for anchoring dyes into the pores of multidimensional zeolites by including organic dye precursors in the synthesis gel has been developed. To prove the concept, an aniline‐functionalised zeolite Beta was obtained by reaction of triethylorthosilicate (TEOS), tetraethylammonium hydroxide, and N‐methyl,N‐(propyl‐3‐trimethoxysilyl)aniline (MPTMSA) in the presence of HF. Further extraction of the structure‐directing agents resulted in a highly crystalline, white, functionalised zeolite Beta containing anchored aniline groups. Similar organic functionalised molecular sieves (OFMS) have been explored as novel catalysts, but, as far as we know, OFMS have never been used as precursors for dye‐immobilisation or to design new solid‐based host systems for selective molecular sensing processes as is reported here. In a second step the solids containing dyes were prepared by reaction of the hybrid material with the appropriate reactives to obtain tricyanovinylbenzene, triphenylpyrylium, azoic, and squaraine derivatives. All these reactions are straightforward and involve electrophilic aromatic substitution or diazotisation reactions at the electron‐rich aniline ring. The final dye‐functionalised solid materials were isolated by simple filtration and washing procedures and have been characterised by a number of techniques. In all cases the Beta structure of the solid remains unaltered. Among the large number of areas where dye‐containing zeolites might be of importance, we were interested in testing their unconventional use as heterosupramolecular hosts in chromogenic protocols. To check their potential use as chemosensors, microporous solids with anchored triphenylpyrilium and squaraine dyes were selected and used as sensors for the chromogenic discrimination of amines. It was found that the response of both solids to amines was basically governed by the three‐dimensional (3D) solid architecture that tuned the intrinsic unselective reactivity of the pyrylium dye. By using new solid‐state supramolecular chemistry protocols we believe that these, and similar future dye–zeolite hosts, might be promising new sensor materials allowing the visible discrimination of selected target guests by size and/or polarity within families or closely related molecules.

Maspin is a serine protease inhibitor that inhibits tumor invasion and metastasis in human breast cancer and is consistently expressed by mammary myoepithelial cells (MECs). To analyze the value of maspin as a marker of the MEC layer of the normal and tumoral canine mammary gland, the immunohistochemical expression of maspin was studied in formalin-fixed tissues from 55 benign and malignant tumors (40 tumors also contained the surrounding normal mammary gland) using a commercially available monoclonal antibody. Periacinar and periductal MECs of all 40 normal mammary glands were stained by the anti-human maspin monoclonal antibody, and immunoreactivity was observed in the nucleus and cytoplasm of these cells. In addition, maspin was found in 53 (98%) of the tumors studied, reacting with the MECs in 100% of benign tumors and 93% of malignant tumors and to the epithelial cells of 16% of benign and 73% of malignant tumors. In the MEC compartment, immunoreactivity was observed in the cytoplasm of hypertrophic MECs, fusiform MECs, stellate MECs, rounded (myoepithelial) cells, and chondroblasts. In the epithelial cell compartment, immunoreactivity was observed in the cytoplasm of cells with and without squamous differentiation. Stromal myofibroblasts were unreactive. Maspin appears to be a very sensitive marker of the normal and neoplastic myoepithelium that, contrary to smooth muscle differentiation markers, does not stain stromal myofibroblasts. In addition, a subset of neoplastic epithelial cells reacted with the maspin antibody. The relationship between maspin expression in different cellular compartments of canine mammary carcinomas and the biologic aggressiveness of the disease remains to be elucidated.

To date, two isoforms of estrogen receptors (ER) have been identified, cloned, and characterized from several species, estrogen receptor-α (ERα) and estrogen receptor-β (ERβ). Although the presence of ERα has been demonstrated in normal and tumoral canine mammary tissues, the issue of ERβ expression has not been addressed in the dog. In this study, we have analyzed the expression of ERβ in formalin-fixed, paraffin-embedded tissue samples of nonaltered mammary gland, 30 malignant (six complex carcinoma, 12 simple carcinoma, three carcinosarcoma, and nine carcinoma or sarcoma in benign tumor), and five benign (one fibroadenoma, one complex papilloma, one complex adenoma, and two benign mixed tumors) mammary tumors of the dog by using a polyclonal ERβ antibody and the avidin-biotin-peroxidase complex immunohistochemical technique. Our results show that high numbers of normal ductal and acinar epithelium and approximately one third of canine mammary tumors express ERβ. This expression was higher in benign than in malignant tumors. Furthermore, expression was higher in complex and mixed histologic subtypes of malignant tumors when compared with simple subtypes.

Spontaneous basaloid adenomas occurred in four out of 354 dogs with mammary tumors. Affected dogs were pure-bred, intact females between 6 and 8 years of age. Three dogs were nuliparous, two had pseudopregnancies, and none had received contraceptive steroids. The tumors were multiple (three cases) or unique, less than 1 cm in diameter, well delineated, and composed of uniform cords and clusters of monomorphic epithelial cells with focal signs of squamous or glandular differentiation. A basal cell immunophenotype (cytokeratins 5 and 14 positive) without either glandular epithelial (cytokeratins 8, 18, and 19 negative) or myoepithelial (calponin negative) differentiation was observed in the majority of tumor cells. No recurrence or metastasis was recorded after follow-up periods between 3 and 24 months. In spite of the hormone-dependent nature of this tumor in female Beagles given experimental contraceptive steroids, spontaneous basaloid adenomas lacked estrogen receptor alpha and progesterone receptors.

Abstract: Mercury levels in the urine of Mexican dentists were determined by instrumental neutron activation analysis. A control group with no suspicion of contamination by mercury was also studied. Acid digestion was used for samples treatment and the presence of 203Hg was determined by gamma spectroscopy. The ranges of mercury concentration found in urine were: for the dentists group from 0.19 to 11.56 mg Hg/l, with a mean value of 3.16 mg Hg/l and standard deviation of 2.74 mg Hg/l, and for the control group from 0.03 to 0.05 mg Hg/l with a mean value of 0.04 mg Hg/l and standard deviation of 0.01 mg Hg/l. The mercury levels found in urine of dentists are associated with several exposure factors which appear to be positively correlated to its concentration, such as years of dental practice, amalgamation techniques, etc.

The immunohistochemical expression of the smooth muscle-specific protein calponin was studied to assess the contribution of myoepithelial cells to the histogenesis of spindle cells of complex and mixed tumors of the mammary gland of the dog and the origin of cartilage and bone in mixed tumors. Formalin-fixed tissues from 55 benign and malignant tumors (49 also containing surrounding normal mammary gland) were evaluated. Periacinar and periductal myoepithelial cells of all the 49 normal mammary glands were diffusely stained by the anti-human calponin monoclonal antibody. Calponin was found in 53 (98%) of the tumors studied, reacting with the myoepithelium-like cells of 86% of benign tumors and their remnants in 85% of malignant tumors. Five different types of calponin-immunoreactive myoepithelial cells were identified: hypertrophic myoepithelial cells, fusiform cells, stellate myoepithelial cells, rounded (myoepithelial) cells, and chondroblasts. Differences in staining intensity and staining pattern among these five types of cells suggested a transition of myoepithelial cells to chondroblasts. Stromal myofibroblasts also showed calponin immunoreactivity, but they did not react with a cytokeratin 14 monoclonal antibody, which recognizes myoepithelial cells in mammary gland. Calponin appears to be a very sensitive marker of normal and neoplastic myoepithelium in the canine mammary gland, and its identification in different cell types of complex and mixed tumors of the mammary gland of the dog suggests a major histogenetic role for myoepithelial cells.

Forty-seven feline and 60 canine epithelial tumors were studied to test the coordinate expression of cytokeratin 7 (CK 7) and cytokeratin 20 (CK 20) using commercially available monoclonal antibodies and an avidin-biotin immunoperoxidase staining technique. Previously, the distribution of both cytokeratins was examined in normal tissues from 4 cats and 4 dogs. The pattern of distribution of CK 7 in normal tissues was similar, with minor differences, to that described in humans, whereas the reactivity pattern of CK 20 in cats and dogs was wider than that in humans. The subset of tumors strongly expressing CK 7 and CK 20 included pancreatic adenocarcinomas (100%), transitional cell carcinomas (75%), and endometrial carcinomas (67%) in the cat. None of the canine tumors had this immunophenotype. Feline (50%) and canine (56%) mammary gland carcinomas and canine cholangiocarcinomas (67%) were the only tumors presenting the CK 7+/CK 20- immunophenotype, whereas the CK 7-/CK 20+ immunophenotype included thyroid carcinomas (100%), intestinal adenocarcinomas (60%), bronchioloalveolar carcinomas (50%), and renal carcinomas (50%) in the cat and intestinal adenocarcinomas (56%), gastric adenocarcinomas (50%), and ovarian carcinomas (50%) in the dog. The CK 7-/CK 20- immunophenotype included the rest of the analyzed tumors. The immunohistochemical evaluation of coordinate expression of both CK 7 and CK 20 in feline and canine carcinomas using monoclonal antibodies provides important information that can help to discriminate among carcinomas from different primary sites and could be particularly helpful in the determination of the primary site of origin of carcinomas presenting as metastatic disease.

Crystallization behaviour of 2826 MB metglas has been studied by transmission electron microscopy and selected area diffraction. Dynamic heating between room temperature and 1100 K and isothermal annealing close to crystallization onset have been performed. Crystallization takes place through a two-stage process to give MSI and MSII phases and details of these are discussed. A new transformation to a stable phase SIII is detected in agreement with the third peak observed by differential thermal analysis experiments.

Previous papers studied ternary tablets containing different concentrations of polyvinylpyrrolidone cross-link (PVP-CL) as disintegrant. The drug percolation threshold, pcl, for these tablets was estimated to fall in the range 0.26-0.31 of total porosity. The aim of the present paper is to study if the presence of the disintegrant agent (PVP-CL) in these tablets, exerts an important effect on the drug percolation threshold obtained. For this purpose, binary tablets containing the same model drug and excipient have been prepared in identical technological conditions. The drug percolation threshold in these matrix tablets has been calculated following the method of Bonny and Leuenberger (5). The results obtained show no significant difference between pcl in the binary matrix tablets and the drug percolation threshold found in the tablets containing the disintegrant agent. This result supposes a stimulus for the application of the principles of percolation theory to a great number of pharmaceutical systems containing disintegrant agents or substances which cause a strong change in its release behavior.

A procedure has been established to obtain the design parameters of the masks used in dispersive correlation spectrometers. The SNR equations are used to derive the mask equations. These are later solved for some simplified band models, and the obtained parameters are used as the initial values in an iterative program which determines the final design parameters. The calculations can be performed for various backgrounds and instrumental line profiles in order to achieve the best compromise for the detection of pollutants, and other trace gases, in the atmosphere.

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Microstructural changes in Fe73.5-xCrxCu1Nb3Si13.5B9 (0?x?5) alloys with thermal treatment were studied by electron microscopy. In a first stage, around 800 K, an Fe(Si) nanocrystalline phase is formed in the amorphous residual matrix. Crystallization onset is enhanced with the Cr content of the alloy. In a second stage, around 950 K, full crystallization of the samples leads to the formation of a body centred cubic (b.c.c.) boride-type unknown crystal phase with a lattice parameter of a=1.52 nm, and recrystallization of the previous Fe(Si) nanophase also occurs. No qualitative differences were found between dynamic and isothermal crystallization. The size effect for thin samples is limited to a lowering of crystallization temperatures. For isothermal nanocrystallization in the temperature range 775–900 K, the mean grain size of the nanocrystals increases for short annealing times to stabilize at a constant value of about 10–15 nm for long annealing times. The stabilized grain size increases with increasing annealing temperature and slightly decreases with the Cr content of the alloy.

Isothermal crystallization kinetics of the Ni63Cr18B13Si6alloy was carried out by differential scanning calorimetry. The JMA approach was used and the mean Avrami exponent values obtained were found to be consistent with a primary precipitation and a polymorphic crystallization, respectively, for the two crystallization stages. The novel concept of the local value of the Avrami exponent was also applied. The nloc−xplot was seen to be independent of the temperature of isothermal crystallization for the two stages, indicating that the crystallization processes depend only on the volume fraction transformed. Finally, the time-scaling law in the kinetic plots was verified.

: We examined the effect of helium-neon (He-Ne) laser irradiation with a wavelength of 632.8 nm on cell cycle synchronisation of monolayer growing mouse myeloma (Sp2-Ag14) cell line. The monolayer cultures were exposed to repeated doses of different energy densities (4–64 J/cm2). The nuclear DNA content has been studied by flow cytometry to obtain the cell percentage in each cell cycle phase. Results showed that the He-Ne laser irradiation at energy densities of 8–64 J/cm2 produced a significative and different effect on the G0–G1 and S phases of cell cycle over control. In contrast, no significant effect in G2–M phase was produced by He-Ne laser irradiation at any energy density compared with non-treated control. These results support previous observations suggesting that He-Ne laser irradiation of low energy density interferes with cell cycling and may inhibit cell proliferation when irradiation is performed at doses of 8 J/cm2 or more.

Abstract.: The effects of laser light on the cellular proliferation have been extensively characterised. Low-power laser sources, such as the helium–neon (He-Ne) laser irradiation with a wavelength of 632.8 nm, have been found to produce photobiological and photodamaging effects with evidence of interference with cell proliferation functions. The present study has investigated the in vitro effect of He-Ne laser irradiation on the proliferative action of dog tumour cells in culture. Dose–response studies showed that repeated He-Ne irradiation (irradiance 12.8 mW/cm2) once a day for 4 consecutive days in a dose range between 0.13 and 2.08 J/cm2 significantly increased with increasing energy density up to a laser dose of 0.26 J/cm2, whereas at >1.04 J/cm2, the cell proliferation decreased with increasing energy densities. It is concluded that the application of He-Ne laser irradiation at energy densities ranging from 0.13 J/cm2 to 2.08 J/cm2 produced different effects on cell proliferation in dog tumour cells in culture.

A 24 years old male with pseudohermaphroditism due to a deficiency in 17-ketosteroid reductase activity is described. Plasma Δ4is 21 times higher than normal for an adult male, Δ4/T is greater than 6, both E1and E2are elevated and E1/E2= 3.There is very slight modification of Δ4on administration of ACTH, dexamethasone, hCG and fluoxymesterone. Steroid concentrations in the spermatic veins and arteries confirm the testicular origin of the increased secretion of Δ4and E1and show a lower secretion by the cryptorchidic testis.In vitro testicular tissue incubation and fibroblast studies confirm the 17-ketosteroid reductase deficiency and rule out any other anomaly as the cause of the ambiguous genitalia.Psychologically the patient seemed to be identified with a female social and sexual role in spite of her advanced degree of virilization.

Contents of arginine, ornithine, urea and ammonia in wine were monitored during aging process by two “flor” veil-forming yeast strains. The patterns of yeast growth were different for the two strains studied. Urea excretion and uptake were dependent on yeast strain, so that finished wines showed different concentrations of urea. The effect of limited aeration was also investigated for Saccharomyces cerevisiaevar. capensis. The results indicated that aeration promoted yeast growth in veil, thus reducing urea concentration until its exhaustion in wine.