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1.
Am J Case Rep ; 24: e938914, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37020407

RESUMEN

BACKGROUND Gastrointestinal tract melanomas are usually of metastatic origin, with primary melanomas being relatively rare. Controversy arises about the existence of primary melanoma in the gastrointestinal tract except in areas where melanocytes exist. The appearance of primary colon melanoma is rare due to the embryological absence of melanocytes in the large intestine, with some authors denying its existence at all. CASE REPORT We present a clinical case of a female patient with a primary melanoma of the descending colon. The patient came to the clinic with nausea without vomiting, abdominal swelling and pain, difficult and irregular defecation, and data on a tumor process of the left colon from the performed colonoscopy. Laparoscopic left hemicolectomy with lymphatic dissection was performed. The conclusion to be drawn from histological results was that the malignancy is poorly-differentiated adenocarcinoma. However, the immunohistochemical examination showed colon melanoma. Postoperative complete dermatological and ophthalmic examinations showed no evidence of a cutaneous or an ocular primary lesion, so we decided that this could be a primary colon melanoma. CONCLUSIONS Because of the colonoscopy we were able to make a detailed histological examination of the tumor, which allowed us to differentiate it from common colon adenocarcinomas. Surgical treatment is important in the removal of the primary tumor. The method of choice, with excellent postoperative results, is laparoscopic left hemicolectomy with selective cut-off of the colic vessels at the site of separation and removal of the affected segment together with the mesentery-bearing regional lymphatic basin.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Melanoma , Humanos , Femenino , Neoplasias del Colon/cirugía , Melanoma/cirugía , Colectomía/métodos , Laparoscopía/métodos
2.
Microvasc Res ; 143: 104386, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35623407

RESUMEN

Appraisal of microvascular erythrocyte velocity as well as aggregation are critical features of hemorheological assessment. Examination of erythrocyte velocity-aggregate characteristics is critical in assessing disorders associated with coagulopathy. Microvascular erythrocyte velocity can be assessed using various methodologic approaches; however, the shared assessment of erythrocyte velocity and aggregation has not been well described. The purpose of this study therefore is to examine three independent erythrocyte assessment strategies with and without experimentally induced aggregation in order to elucidate appropriate analytic strategy for combined velocity/aggregation assessment applicable to in-vivo capillaroscopy. We employed a hierarchical microfluidic model combined with Bland-Altman analysis to examine agreement between three methodologies to assess erythrocyte velocity appropriate for interpretation of cinematography of in-vivo microvascular hemorheology. We utilized optical and manual techniques as well as a technique which we term transversal temporal cross-correlation (TTC) to observe and measure both erythrocyte velocity and aggregation. In general, optical, manual and TTC agree in estimation of velocity at relatively low flow rate, however with an increase in infusion rate the optical flow method yielded the velocity estimates that were lower than the TTC and manual velocity estimates. We suggest that this difference was due to the fact that slower moving particles close to the channel wall were better illuminated than faster particles deeper in the channel which affected the optical flow analysis. Combined velocity/aggregation appraisal using TTC provides an efficient approach for estimating erythrocyte aggregation appropriate for in-vivo applications. We demonstrated that the optical flow and TTC analyses can be used to estimate erythrocyte velocity and aggregation both in ex-vivo microfluidics laboratory experiments as well as in-vivo recordings. The simplicity of TTC method may be advantageous for developing velocity estimate methods to be used in the clinic. The trade-off is that TTC estimation cannot capture features of the flow based on optical flow analysis of individually tracked particles.


Asunto(s)
Agregación Eritrocitaria , Flujo Optico , Visualización de Datos , Deformación Eritrocítica , Eritrocitos , Hemorreología
3.
BMC Genomics ; 22(1): 101, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33535965

RESUMEN

BACKGROUND: With numerous endemic subspecies representing four of its five evolutionary lineages, Europe holds a large fraction of Apis mellifera genetic diversity. This diversity and the natural distribution range have been altered by anthropogenic factors. The conservation of this natural heritage relies on the availability of accurate tools for subspecies diagnosis. Based on pool-sequence data from 2145 worker bees representing 22 populations sampled across Europe, we employed two highly discriminative approaches (PCA and FST) to select the most informative SNPs for ancestry inference. RESULTS: Using a supervised machine learning (ML) approach and a set of 3896 genotyped individuals, we could show that the 4094 selected single nucleotide polymorphisms (SNPs) provide an accurate prediction of ancestry inference in European honey bees. The best ML model was Linear Support Vector Classifier (Linear SVC) which correctly assigned most individuals to one of the 14 subspecies or different genetic origins with a mean accuracy of 96.2% ± 0.8 SD. A total of 3.8% of test individuals were misclassified, most probably due to limited differentiation between the subspecies caused by close geographical proximity, or human interference of genetic integrity of reference subspecies, or a combination thereof. CONCLUSIONS: The diagnostic tool presented here will contribute to a sustainable conservation and support breeding activities in order to preserve the genetic heritage of European honey bees.


Asunto(s)
Evolución Biológica , Polimorfismo de Nucleótido Simple , Animales , Abejas/genética , Europa (Continente) , Genotipo , Geografía
4.
Opt Express ; 26(18): 22783-22792, 2018 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-30184933

RESUMEN

Multi-core optical fibers are readily used in endoscopic devices to transmit classical images. As an extension to the quantum domain, we study the transmission of the spatial quantum fluctuations of light through a conduit made of the ordered packing of thousands of fibers. Starting from twin beams that are correlated in their local intensity fluctuations, we show that, in the limit of a high density of constituent fiber cores, the intensity-difference squeezing present in arbitrary matching regions of the beams is preserved when one of the beams is sent through the conduit. The capability of using fiber bundles to transport quantum information encoded in the spatial degrees of freedom could bring guided-light technology to the emergent field of quantum imaging.

5.
Sci Rep ; 8(1): 2023, 2018 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-29386536

RESUMEN

Recent advances in the understanding and control of quantum technologies, such as those based on cold atoms, have resulted in devices with extraordinary metrological performance. To realise this potential outside of a lab environment the size, weight and power consumption need to be reduced. Here we demonstrate the use of laser powder bed fusion, an additive manufacturing technique, as a production technique relevant to the manufacture of quantum sensors. As a demonstration we have constructed two key components using additive manufacturing, namely magnetic shielding and vacuum chambers. The initial prototypes for magnetic shields show shielding factors within a factor of 3 of conventional approaches. The vacuum demonstrator device shows that 3D-printed titanium structures are suitable for use as vacuum chambers, with the test system reaching base pressures of 5 ± 0.5 × 10-10 mbar. These demonstrations show considerable promise for the use of additive manufacturing for cold atom based quantum technologies, in future enabling improved integrated structures, allowing for the reduction in size, weight and assembly complexity.

6.
Opt Express ; 24(24): 27298-27308, 2016 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-27906302

RESUMEN

We experimentally study a homodyne detection technique for the characterization of a quadrature squeezed field where the correlated bands, here created by four-wave mixing in a hot atomic vapor, are separated by a large frequency gap of more than 6 GHz. The technique uses a two-frequency local oscillator to detect the fluctuations of the correlated bands at a frequency accessible to the detection electronics. Working at low detection frequency, the method allows for the determination of both the amplitude and the phase of the squeezing spectrum. In particular, we show that the quadrature squeezing created by our four-wave mixing process displays a noise ellipse rotation of π/2 across the squeezing spectrum.

7.
Folia Biol (Krakow) ; 59(3-4): 121-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22195464

RESUMEN

The genetic variability of honey bee populations of three subspecies selectively reared in Poland (A. m. carnica and A. m. caucasica) and Bulgaria (A. m. macedonica-type rodopica) was studied using isoenzyme analysis of six enzyme systems (MDH-1, ME, EST-3, ALP, PGM and HK) corresponding to 6 loci. All loci were found to be polymorphic in the studied populations. Three alleles were detected at each locus: MHD-1 (MDH65, MDH80 and MDH100), Me (ME90, ME100 and ME106), EST-3 (EST94, EST100 and EST118), ALP (ALP80 ALP90 and ALP100), PGM (PGM80, PGM100 and PGM114) and HK (HK87, HK100 and HK110). The observed and expected heterozygosities (Ho and He) ranged from 0.196 (A. m. macedonica SM) to 0.265 (A. m. carnica MV) and from 0.224 (A. m. macedonica SM) to 0.273 (A. m. carnica GR), respectively. Allele frequencies of all loci were used to estimate Nei's (1972) genetic distance, which was found to range from 0.003 (between A. m. macedonica TR and SM and between A. m. carnica GR and MV populations) to 0.057 (between A. m. macedonica SM and A. m. caucasica populations). The estimated mean F(ST) value from allozyme data was 0.0364. A UPGMA dendrogram was obtained by genetic distance matrix methods; A. m. macedonica (type rodopica), A. m. carnica and A. m. caucasica populations represented different clades.


Asunto(s)
Abejas/genética , Isoenzimas/genética , Filogenia , Polimorfismo Genético , Animales , Abejas/clasificación , Bulgaria , Polonia
8.
Drug Discov Today ; 16(23-24): 1019-30, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22024215

RESUMEN

The increase in drug research output from patent applications, together with the expansion of public data collections, such as ChEMBL and PubChem BioAssay, has made it essential for pharmaceutical companies to integrate both internal and external 'SAR estate'. The AstraZeneca response has been the development of an enterprise application, Chemistry Connect, containing 45 million unique chemical structures from 18 internal and external data sources. It includes merged compound-to-assay-to-result-to-target relationships extracted from patents, papers and internal data. Users can explore connections between these by searching using drug names or synonyms, chemical structures, patent numbers and target protein identifiers at a scale not previously available.


Asunto(s)
Bases de Datos Factuales , Descubrimiento de Drogas/métodos , Preparaciones Farmacéuticas/química , Farmacología , Biología Computacional/métodos , Humanos , Relación Estructura-Actividad
9.
J Chromatogr A ; 1218(2): 343-9, 2011 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-21159344

RESUMEN

A number of 20 compounds of linear alkylbenzene sulfonates (LASs) family were identified by electron impact mass spectrometry (EI-MS) in water samples collected from wastewater treatment plants (WWTP). This paper presents the mass spectra of 20 compounds, the proposed mechanism of formation of the diagnostic ions obtained by EI-MS and the distribution of individual isomers in water samples collected from compartments of WWTP. The individual isomers from four homolog series C(10)-, C(11)-, C(12)- and C(13)-LAS were analyzed as methyl derivatives.


Asunto(s)
Bencenosulfonatos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Contaminantes Químicos del Agua/análisis , Adsorción , Bencenosulfonatos/química , Isomerismo , Contaminantes Químicos del Agua/química , Zeolitas/química
10.
Appl Opt ; 41(9): 1677-84, 2002 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-11921795

RESUMEN

Hermite-Gaussian modes in geometrically unconfined resonators with a four-level system saturable gain guide inside are experimentally observed and proved. The gain guide was formed with a polished cylindrical surface low-concentration Nd:YAG rod exposed to isotropic pump radiation. The connection of the mode scaling factor with the system parameters is compared with the theory. The abilities of the recently established gain-saturation guiding mechanism to support the generation of beams with wide tops and rapidly decreasing intensity in the wings are also experimentally proved. Application areas for saturable gain guiding are briefly discussed.

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