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1.
Phys Rev Lett ; 130(24): 242501, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37390416

RESUMEN

Excited-state spectroscopy from the first experiment at the Facility for Rare Isotope Beams (FRIB) is reported. A 24(2)-µs isomer was observed with the FRIB Decay Station initiator (FDSi) through a cascade of 224- and 401-keV γ rays in coincidence with ^{32}Na nuclei. This is the only known microsecond isomer (1 µs≤T_{1/2}<1 ms) in the region. This nucleus is at the heart of the N=20 island of shape inversion and is at the crossroads of the spherical shell-model, deformed shell-model, and ab initio theories. It can be represented as the coupling of a proton hole and neutron particle to ^{32}Mg, ^{32}Mg+π^{-1}+ν^{+1}. This odd-odd coupling and isomer formation provides a sensitive measure of the underlying shape degrees of freedom of ^{32}Mg, where the onset of spherical-to-deformed shape inversion begins with a low-lying deformed 2^{+} state at 885 keV and a low-lying shape-coexisting 0_{2}^{+} state at 1058 keV. We suggest two possible explanations for the 625-keV isomer in ^{32}Na: a 6^{-} spherical shape isomer that decays by E2 or a 0^{+} deformed spin isomer that decays by M2. The present results and calculations are most consistent with the latter, indicating that the low-lying states are dominated by deformation.


Asunto(s)
Núcleo Celular , Corazón , Isótopos , Neutrones
2.
Artículo en Inglés | MEDLINE | ID: mdl-37028170

RESUMEN

A selective and sensitive liquid chromatography-tandem mass spectrometry method was developed and validated for accurate determination of CHF6550 and its main metabolite in rat plasma and lung homogenate samples. All biological samples were prepared by simple protein precipitation method using deuterated internal standards. The analytes were separated on a HSS T3 analytical column with 3.2 min run time at flow rate of 0.5 mL/min. The detection was performed on a triple-quadrupole tandem mass spectrometer equipped with positive-ion electrospray ionization by selected-reaction monitoring of the transitions at m/z 735.3 â†’ 98.0 for CHF6550 and m/z 638.3 â†’ 319.2 and 638.3 â†’ 376.2 for CHF6671. The calibration curves for plasma samples were linear between 50 and 50000 pg/mL for both analytes. The calibration curves for lung homogenate samples were linear within 0.1-100 ng/mL for CHF6550 and 0.3-300 ng/mL for CHF6671. The method was successfully applied to a 4-week toxicity study.


Asunto(s)
Plasma , Espectrometría de Masas en Tándem , Ratas , Animales , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Estándares de Referencia , Plasma/química , Calibración , Reproducibilidad de los Resultados
3.
Phys Rev Lett ; 129(21): 212501, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36461950

RESUMEN

New half-lives for exotic isotopes approaching the neutron drip-line in the vicinity of N∼28 for Z=12-15 were measured at the Facility for Rare Isotope Beams (FRIB) with the FRIB decay station initiator. The first experimental results are compared to the latest quasiparticle random phase approximation and shell-model calculations. Overall, the measured half-lives are consistent with the available theoretical descriptions and suggest a well-developed region of deformation below ^{48}Ca in the N=28 isotones. The erosion of the Z=14 subshell closure in Si is experimentally confirmed at N=28, and a reduction in the ^{38}Mg half-life is observed as compared with its isotopic neighbors, which does not seem to be predicted well based on the decay energy and deformation trends. This highlights the need for both additional data in this very exotic region, and for more advanced theoretical efforts.

5.
Braz J Med Biol Res ; 46(5): 426-32, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23739746

RESUMEN

Neonatal handling induces several behavioral and neurochemical alterations in pups, including decreased responses to stress and reduced fear in new environments. However, there are few reports in the literature concerning the behavioral effects of this neonatal intervention on the dams during the postpartum period. Therefore, the aim of the current study was to determine if brief postpartum separation from pups has a persistent impact on the dam's stress response and behavior. Litters were divided into two neonatal groups: 1) non-handled and 2) handled [10 min/day, from postnatal day (PND) 1 to 10]. Weaning occurred at PND 21 when behavioral tasks started to be applied to the dams, including sweet food ingestion (PND 21), forced swimming test (PND 28), and locomotor response to a psychostimulant (PND 28). On postpartum day 40, plasma was collected at baseline for leptin assays and after 1 h of restraint for corticosterone assay. Regarding sweet food consumption, behavior during the forced swimming test or plasma leptin levels did not differ between dams briefly separated and non-separated from their pups during the postpartum period. On the other hand, both increased locomotion in response to diethylpropion and increased corticosterone secretion in response to acute stress were detected in dams briefly separated from their pups during the first 10 postnatal days. Taken together, these findings suggest that brief, repeated separations from the pups during the neonatal period persistently impact the behavior and induce signs of dopaminergic sensitization in the dam.


Asunto(s)
Animales Recién Nacidos , Corticosterona/sangre , Leptina/sangre , Privación Materna , Actividad Motora/fisiología , Estrés Psicológico/fisiopatología , Animales , Animales Recién Nacidos/sangre , Femenino , Humanos , Masculino , Embarazo , Ratas Wistar , Estrés Psicológico/sangre , Natación , Factores de Tiempo
6.
Braz. j. med. biol. res ; 46(5): 426-432, maio 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-675672

RESUMEN

Neonatal handling induces several behavioral and neurochemical alterations in pups, including decreased responses to stress and reduced fear in new environments. However, there are few reports in the literature concerning the behavioral effects of this neonatal intervention on the dams during the postpartum period. Therefore, the aim of the current study was to determine if brief postpartum separation from pups has a persistent impact on the dam's stress response and behavior. Litters were divided into two neonatal groups: 1) non-handled and 2) handled [10 min/day, from postnatal day (PND) 1 to 10]. Weaning occurred at PND 21 when behavioral tasks started to be applied to the dams, including sweet food ingestion (PND 21), forced swimming test (PND 28), and locomotor response to a psychostimulant (PND 28). On postpartum day 40, plasma was collected at baseline for leptin assays and after 1 h of restraint for corticosterone assay. Regarding sweet food consumption, behavior during the forced swimming test or plasma leptin levels did not differ between dams briefly separated and non-separated from their pups during the postpartum period. On the other hand, both increased locomotion in response to diethylpropion and increased corticosterone secretion in response to acute stress were detected in dams briefly separated from their pups during the first 10 postnatal days. Taken together, these findings suggest that brief, repeated separations from the pups during the neonatal period persistently impact the behavior and induce signs of dopaminergic sensitization in the dam.


Asunto(s)
Animales , Femenino , Humanos , Masculino , Embarazo , Animales Recién Nacidos , Corticosterona/sangre , Leptina/sangre , Privación Materna , Actividad Motora/fisiología , Estrés Psicológico/fisiopatología , Animales Recién Nacidos/sangre , Ratas Wistar , Natación , Estrés Psicológico/sangre , Factores de Tiempo
7.
Artículo en Inglés | MEDLINE | ID: mdl-21574080

RESUMEN

During feed preparation at feed mills or during feed mixing in bins at farms, the accidental contamination of feed at trace levels by veterinary drug residues, commonly known as carry-over, can accidentally but frequently occur. To evaluate the concentrations of residual antimicrobials in poultry edible tissues, due to contaminated feed, sulfadimethoxine and doxycycline were administered for 10 days to chickens in poultry feed incurred at the contamination levels frequently found during national feed monitoring programmes (1-5 mg kg(-1)). Sulfadimethoxine and doxycycline residual concentrations detected in muscle (

Asunto(s)
Alimentación Animal/análisis , Pollos/metabolismo , Doxiciclina/análisis , Contaminación de Alimentos/análisis , Sulfadimetoxina/análisis , Alimentación Animal/toxicidad , Animales , Doxiciclina/toxicidad , Residuos de Medicamentos/análisis , Residuos de Medicamentos/toxicidad , Contaminación de Alimentos/legislación & jurisprudencia , Inocuidad de los Alimentos , Humanos , Italia , Límite de Detección , Concentración Máxima Admisible , Sulfadimetoxina/toxicidad , Distribución Tisular , Drogas Veterinarias/análisis , Drogas Veterinarias/toxicidad
8.
Anal Chim Acta ; 637(1-2): 173-7, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19286026

RESUMEN

The study was intended to evaluate the depletion of chloramphenicol (CAP) in rainbow trout (about 300-550 g body weight), after 10 days treatment with fish feedstuff containing chloramphenicol. A total of 60 animals were separated in two groups: one was fed with CAP containing feedstuff in order to have a dosage of about 80 mgkg(-1)day(-1), while a second group of fishes was fed with feedstuff not containing any CAP formulation (negative controls). The treatment was maintained for 10 days. After this period, groups of 2-5 animals were sacrificed at different withdrawal times up to a maximum of 31 days. Muscle tissues of each group of animals were then analysed for quantitative residual CAP determination both by enzyme linked immunoassay (ELISA) and liquid chromatography coupled to mass spectrometry (HPLC/MSMS). The methods applied were in house validated according to the guidelines laid down by the European Decision 657/2002/EC. Results and considerations are presented.


Asunto(s)
Antibacterianos/análisis , Cloranfenicol/análisis , Cromatografía Líquida de Alta Presión/métodos , Residuos de Medicamentos/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Oncorhynchus mykiss/metabolismo , Espectrometría de Masas en Tándem/métodos , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Cloranfenicol/administración & dosificación , Cloranfenicol/farmacocinética , Residuos de Medicamentos/aislamiento & purificación , Enfermedades de los Peces/tratamiento farmacológico , Músculos/química , Extracción en Fase Sólida
9.
Artículo en Inglés | MEDLINE | ID: mdl-24784967

RESUMEN

Antibacterial drugs are used worldwide for the control of American and, less often, European foulbrood. Their administration is mostly uncontrolled and applied without approved protocols and instructions for use as well as precautionary recommendations. Consequently, this practice is responsible for the contamination of beehive products and contributes to the problem of food safety. According to this situation, 4672 analyses were carried out on 5303 honeys collected from 2001 to 2007. These samples were investigated for antibacterial residues of tetracyclines, sulphonamides, streptomycin, chloramphenicol and tylosin. Honeys were classified according to their origin: imported honey and honey from the Italian market. In the last group (only for samples collected from 2001 to 2004), another type of honey was distinguished: that of local honey. A total of 6.3% of all samples were positive for the antibacterial drugs analysed; in particular, 6.8% of imported honeys and 6.1% of honeys on the Italian market. Only 1.7% of local honey had antibacterial residues. These results are indicative of a rather frequent presence of antibacterial drug residues in both Italian and imported honeys. Furthermore, the data showed that among the active substances analysed, sulphonamides are the most used antibacterial substance followed by tetracyclines, streptomycin, tylosin, and chloramphenicol. Finally, a continuous monitoring programme is needed, accompanied by an education programme to beekeepers on proper hive management.


Asunto(s)
Antibacterianos/análisis , Residuos de Medicamentos/análisis , Contaminación de Alimentos/análisis , Miel/análisis , Animales , Antibacterianos/toxicidad , Apicultura , Abejas , Cloranfenicol/análisis , Cloranfenicol/toxicidad , Residuos de Medicamentos/toxicidad , Análisis de los Alimentos/métodos , Miel/toxicidad , Humanos , Italia , Estreptomicina/análisis , Estreptomicina/toxicidad , Sulfonamidas/análisis , Sulfonamidas/toxicidad , Tetraciclinas/análisis , Tetraciclinas/toxicidad , Tilosina/análisis , Tilosina/toxicidad
10.
Anal Chim Acta ; 617(1-2): 132-8, 2008 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-18486648

RESUMEN

A fast, simple and very selective liquid chromatography-mass spectrometry (LC-MS) method for the detection of isopropylthioxanthone (ITX) in dairy products has been developed and validated. After addition of an ITX-d(3) as internal standard and a simple extraction from the sample with acetonitrile, the extract was centrifuged and directly injected into the LC-MS system. Chromatographic separation was achieved by means of a Gemini C18 column (100 mm x 2.0 mm i.d. 5 microm) using a gradient of aqueous 20 mM ammonium formiate at pH 4.5 and methanol as the mobile phase, at a flow rate of 0.25 mL min(-1). The method was validated according to the guidelines laid down by the Commission Decision 2002/657/EC using the parent ion [M+H](+) (m/z 255) as quantification ion, and the fragment ion (m/z 213) obtained by in-source collision-induced dissociation (IS-CID) as confirmation ion. Absolute and relative recoveries rates were verified at 5, 10, 15 microg kg(-1) in yoghurt samples and at 5 microg kg(-1) in milk and pudding: mean absolute recoveries were 77% in yoghurt, 50% in pudding and 67% in milk; relative recoveries (after internal standard correction) were always >97% in each matrix. The detection limit (CCalpha) and the detection capability (CCbeta) of method were 6.2 and 7.2 microg kg(-1), respectively.

11.
Food Addit Contam ; 23(11): 1099-108, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17071512

RESUMEN

A sensitive and specific method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), for the simultaneous determination of lincomycin and five macrolide antibiotics in honey, was developed and validated. The analytes were extracted with Tris buffer 0.1 M, pH 10.5, and cleaned-up by a single solid-phase extraction step on OASIS HLB column. The chromatographic separation of analytes was performed on a Synergi Hydro-RP reversed-phase column using a gradient programme of aqueous 0.01 M ammonium acetate, pH 3.5, and acetonitrile as the mobile phase, at a flow rate 0.25 ml min-1. The detection of analytes was achieved by positive ionization electrospray in multiple reaction-monitoring mode. Two characteristic transitions were monitored for each substance. The following analytical parameters were validated according to the guidelines laid down by European Commission Decision 2002/657/EC (European Commission 2002): linearity, specificity, decision limit (CCalpha), detection capability (CCbeta), repeatability, within-laboratory reproducibility, recovery and ruggedness.


Asunto(s)
Antibacterianos/análisis , Cromatografía Líquida de Alta Presión/métodos , Miel/análisis , Lincomicina/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Animales , Residuos de Medicamentos/análisis , Macrólidos/análisis , Reproducibilidad de los Resultados
12.
J Feline Med Surg ; 4(4): 201-3, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12468313

RESUMEN

Several techniques for castration of cryptorchid cats have been described. In this case report, the use of laparoscopy for castration of a bilateral cryptorchid cat (with testes located in the abdomen) is described. Three trocars were inserted into the abdominal cavity, the testicles were easily identified adjacent to the urinary bladder. Haemostasis of the gubernaculum testis and spermatic cord was achieved with bipolar cauterisation. The testicles were easily removed in approximately 20 min. To the authors' knowledge this is the first report of the use of laparoscopy for the treatment of cryptorchidism in cats.


Asunto(s)
Enfermedades de los Gatos/cirugía , Criptorquidismo/veterinaria , Animales , Gatos , Criptorquidismo/cirugía , Laparoscopía/métodos , Laparoscopía/veterinaria , Masculino , Orquiectomía/métodos , Orquiectomía/veterinaria
13.
Minerva Stomatol ; 44(3): 119-26, 1995 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-7623753

RESUMEN

The authors report a rare case of non-familial cherubism with a six-year follow-up. After an analysis of the hereditary transmission of the disease, the authors evaluate the anatomopathological and radiological characteristics and differential diagnosis, and then discuss possible therapies in the light of the latest research. They underline the important role of CT in identifying lesions which may not be diagnosed by simple X-ray with orthopantomography and highlight the importance of taking extreme care to conserve as much dental and bone tissue as possible during surgery.


Asunto(s)
Querubismo/diagnóstico , Biopsia , Querubismo/genética , Querubismo/patología , Querubismo/cirugía , Niño , Diagnóstico Diferencial , Humanos , Maxilares/diagnóstico por imagen , Maxilares/patología , Masculino , Procedimientos Quirúrgicos Ortognáticos , Pronóstico , Radiografía Panorámica , Tomografía Computarizada por Rayos X
14.
Rev Hosp Clin Fac Med Sao Paulo ; 49(5): 221-4, 1994.
Artículo en Portugués | MEDLINE | ID: mdl-7716376

RESUMEN

Primary gastric lymphoma is a relatively rare entity that may have several different methods of treatment, including surgery, chemotherapy and radiotherapy. We describe a case of advanced primary gastric lymphoma treated with chemotherapy. A 51-year-old male patient underwent total gastrectomy after two cycles of chemotherapy. The histologic examination of the gross specimen revealed total regression of the lymphoma. Literature review of this condition and a discussion about the diagnosis and treatment are presented.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma no Hodgkin/tratamiento farmacológico , Neoplasias Gástricas/tratamiento farmacológico , Terapia Combinada , Ciclofosfamida/administración & dosificación , Humanos , Linfoma no Hodgkin/radioterapia , Linfoma no Hodgkin/cirugía , Masculino , Persona de Mediana Edad , Prednisona/administración & dosificación , Inducción de Remisión , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/cirugía , Vincristina/administración & dosificación
16.
Dent Cadmos ; 59(6): 36-40, 43-4, 1991 Apr 15.
Artículo en Italiano | MEDLINE | ID: mdl-2070923

RESUMEN

Discussing the central intraosseous developmental odontogenic cysts of the jaws the Authors have followed the classification suggested by Hoffman et Al. that lists the lesions according to their biological activity. After a short foreword about the most important stages of the embryological dental development, grouped in six phases, the Authors referred to the principal concepts emerging from the literature about the most aggressive developmental odontogenic cysts of the jaws: the primordial cyst and the odontogenic keratocyst of which they have outlined a definition, and referred to the clinical, radiological, ethiological and microscopical data, the treatment and the differential diagnosis.


Asunto(s)
Quistes Maxilomandibulares , Quistes Odontogénicos , Adulto , Niño , Femenino , Humanos , Masculino , Odontogénesis , Erupción Dental
17.
Dent Cadmos ; 59(6): 48-50, 53-8, 61-4 passim, 1991 Apr 15.
Artículo en Italiano | MEDLINE | ID: mdl-2070924

RESUMEN

The Authors conclude the chapter about the central intraosseous developmental odontogenic cysts. Some of them are very rare, others are very similar histogenetically with other more frequent cystic lesions of the jaws. Notwithstanding the radiographic and macroscopic aspect apparently similar, these lesions are very different between each other in their biological activity. The classification, suggested by Hoffman, Jacoway and Krolls lists these lesions from the least to the most aggressive. We have here considered the multiple nevoid basal cell carcinoma syndrome, also known as Gorlin-Goltz syndrome, associated to one or more keratinized maxillary cysts, the calcifying odontogenic cyst, the more frequent and well known dentigerous cyst, the lateral periodontal cyst with its uncertain etiology and the harmless eruption cyst.


Asunto(s)
Quistes Maxilomandibulares , Síndrome del Nevo Basocelular , Quiste Dentígero , Quiste Folicular , Humanos , Neoplasias Maxilomandibulares , Quistes Odontogénicos , Tumores Odontogénicos , Quiste Periodontal , Erupción Dental
19.
Dent Cadmos ; 59(6): 80-4, 87-90, 93-5, 1991 Apr 15.
Artículo en Italiano | MEDLINE | ID: mdl-2070926

RESUMEN

The apical granuloma, the periapical abcess and the radicular cyst are the most frequent between the inflammatory odontogenic lesions of the jaws. These three lesions are caused by the necrosis of the pulp but are very different between each other from an histological point of view and they can correspond to different stages of the same pathological process considering the fact that from a granuloma can arise a periapical abcess or a radicular cyst and from a radicular cyst and abcess can originate. About these three pathological processes we discuss in this article the clinical, radiographical, ethiological, microscopical features, we suggest the treatment and the differential diagnosis.


Asunto(s)
Absceso Periapical , Granuloma Periapical , Quiste Radicular , Resorción Ósea , Caries Dental/complicaciones , Necrosis de la Pulpa Dental/complicaciones , Humanos , Inflamación , Absceso Periapical/etiología , Granuloma Periapical/etiología , Quiste Radicular/etiología
20.
Dent Cadmos ; 59(6): 96-102, 105-8, 1991 Apr 15.
Artículo en Italiano | MEDLINE | ID: mdl-2070927

RESUMEN

The Authors presented the clinical report of an apical scar because of the rareness of the case and because of the interesting differential diagnosis: this lesion has a cystic radiological aspect and must be differentiated from the real odontogenic cysts of the jaws; the apical scar does not belong to the cystic pathology and represents just a defect of the healing process: no treatment is requested as the apical scar mustn't be considered a pathology.


Asunto(s)
Cicatriz , Cicatrización de Heridas , Cicatriz/diagnóstico , Diagnóstico Diferencial , Humanos , Quistes Maxilomandibulares/diagnóstico , Enfermedades Periapicales/diagnóstico , Quiste Radicular/diagnóstico , Tratamiento del Conducto Radicular
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