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1.
Nat Food ; 4(1): 35-50, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-37118574

RESUMEN

Cellular agriculture could meet growing demand for animal products, but yields are typically low and regulatory bodies restrict genetic modification for cultured meat production. Here we demonstrate the spontaneous immortalization and genetic stability of fibroblasts derived from several chicken breeds. Cell lines were adapted to grow as single-cell suspensions using serum-free culture medium, reaching densities of 108 × 106 cells per ml in continuous culture, corresponding to yields of 36% w/v. We show that lecithin activates peroxisome proliferator-activated receptor gamma (PPARγ), inducing adipogenesis in immortalized fibroblasts. Blending cultured adipocyte-like cells with extruded soy protein, formed chicken strips in which texture was supported by animal and plant proteins while aroma and flavour were driven by cultured animal fat. Visual and sensory analysis graded the product 4.5/5.0, with 85% of participants extremely likely to replace their food choice with this cultured meat product. Immortalization without genetic modification and high-yield manufacturing are critical for the market realization of cultured meat.


Asunto(s)
Pollos , Carne , Animales , Pollos/genética , Adipogénesis , Fibroblastos , Línea Celular
2.
Phys Rev Lett ; 109(13): 138701, 2012 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-23030127

RESUMEN

Current methods for evaluating solar cell efficiencies cannot be applied to low-dimensional structures where phenomena from the realm of near-field optics prevail. We present a theoretical approach to analyze solar cell performance by allowing rigorous electromagnetic calculations of the emission rate using the fluctuation-dissipation theorem. Our approach shows the direct quantification of the voltage, current, and efficiency of low-dimensional solar cells. This approach is demonstrated by calculating the voltage and the efficiency of a GaAs slab solar cell for thicknesses from several microns down to a few nanometers. This example highlights the ability of the proposed approach to capture the role of optical near-field effects in solar cell performance.

4.
Acta Otolaryngol ; 126(3): 334-6, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16618667

RESUMEN

This report describes the case of an elderly, diabetic man who developed acute suppurative parotitis with abscess formation. The causative agent of parotid abscess was Candida albicans, which is an unusual cause of salivary gland pathology. The parotid gland is the salivary gland most commonly affected by inflammation. Acute parotitis occurs most often in elderly patients who are debilitated by systemic disease or are in a state of dehydration following major surgical procedures. Despite the high prevalence of oral candida carriage, there have been few previous reports of candida sialoadenitis in the literature. This is due to the toxicity of saliva to fungi under normal conditions. The diagnosis of candidiasis in our patient was made by culturing the purulent discharge from Stensen's duct and by culture of the pus obtained at surgical drainage of the abscess. After incision and drainage, the patient was treated with intravenous and then oral fluconazole for a total of 4 weeks with complete resolution of his condition. This case is interesting in light of recent and ongoing investigations of salivary proteins as potential new antifungal agents.


Asunto(s)
Absceso/diagnóstico , Candida albicans/aislamiento & purificación , Candidiasis/diagnóstico , Parotiditis/diagnóstico , Absceso/terapia , Enfermedad Aguda , Anciano , Candidiasis/terapia , Terapia Combinada , Medios de Contraste , Drenaje/métodos , Fluconazol/uso terapéutico , Estudios de Seguimiento , Humanos , Masculino , Parotiditis/terapia , Medición de Riesgo , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
5.
Arch Otolaryngol Head Neck Surg ; 127(6): 709-13, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11405874

RESUMEN

Wegener's granulomatosis is a chronic debilitating disease with multiple organ system involvement, variable course, and myriad complications that cause morbidity and mortality. We report 2 cases of nasal cavity squamous cell carcinoma occurring in long-standing Wegener's granulomatosis.


Asunto(s)
Carcinoma de Células Escamosas/etiología , Granulomatosis con Poliangitis/complicaciones , Cavidad Nasal , Neoplasias Nasales/etiología , Adulto , Carcinoma de Células Escamosas/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Cavidad Nasal/patología , Neoplasias Nasales/patología
6.
Int J Pediatr Otorhinolaryngol ; 48(2): 155-62, 1999 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-10375041

RESUMEN

Infections of the orbit in children usually present as a complication of sinusitis and may result in blindness or even death. Orbital cellulitis (OC) and subperiosteal abscess (SPA) represent different pathologies within the spectrum of orbital infections. The differentiation between OC and SPA is important, since it implies two different therapeutic modalities. While SPA is usually treated by incision and drainage and parenteral antibiotics, OC may be treated with antibiotics alone. Contrast enhanced CT scan is commonly used in the diagnosis of orbital infections, but does not always prove accurate in differentiating between these two conditions. MRI is superior to CT in the resolution of soft tissue pathology and may be more precise in such situations, but is less available imaging tool outside North America and Europe. There have been a few reports in the early 1980's on the use of standardized orbital ultrasound (SOU) in these two conditions. We have used SOU in seven children with sinus induced orbital infections--four with SPA and three with OC. We reviewed our experience in these patients and compared the imaging characteristics of OC and SPA on SOU with those of conventional imaging modalities, used in orbital infections. In four of the cases, CT scan was inconclusive, while SUO was diagnostic. In this preliminary report, we conclude that SOU may be useful in the diagnosis of orbital infections.


Asunto(s)
Absceso/diagnóstico por imagen , Enfermedades Orbitales/diagnóstico por imagen , Sinusitis/complicaciones , Absceso/complicaciones , Adolescente , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Enfermedades Orbitales/etiología , Tomografía Computarizada por Rayos X , Ultrasonografía
7.
Int J Pediatr Otorhinolaryngol ; 49(3): 177-83, 1999 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-10519696

RESUMEN

INTRODUCTION: The clinical picture of lateral sinus thrombosis (LST) has changed with the advent of antibiotics, as have the utility of various diagnostic tests. LST may appear in children as a complication of acute otitis media, but nowadays it is more frequently encountered in adults with long-standing chronic ear disease. METHOD: A retrospective study of all the pediatric patients with LST between 1982 and 1997. RESULTS: Thirteen cases of LST were diagnosed and treated by our department. In six cases, LST was due to acute otitis media and in the remaining cases it was due to chronic otitis media. Headache, fever, aural discharge and mastoid tenderness were the most frequent findings in these patients and four patients were initially diagnosed with meningitis. In the majority of the patients, LST was accompanied with other intracranial complications, such as perisinus abscess, brain abscess and meningitis. One patient with multiple brain abscesses, unresponsive to several drainage procedures, died. The other patients recovered and have since been followed-up as out-patients. CONCLUSION: LST may be difficult to diagnose due to previous antibiotic treatment and to the overlap of clinical findings with other entities such as meningitis. Despite the value of modern imaging techniques in the investigation of the disease, a high index of suspicion based on the clinical picture is warranted. Our results are consistent with those of other recent studies, who found that mortality of LST has dropped below 10%.


Asunto(s)
Trombosis del Seno Lateral/etiología , Otitis Media con Derrame/complicaciones , Enfermedad Aguda , Adolescente , Antibacterianos/uso terapéutico , Absceso Encefálico/complicaciones , Absceso Encefálico/tratamiento farmacológico , Absceso Encefálico/microbiología , Cerebelo/microbiología , Niño , Preescolar , Enfermedad Crónica , Terapia Combinada , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Infecciones por Haemophilus/complicaciones , Infecciones por Haemophilus/tratamiento farmacológico , Humanos , Lactante , Trombosis del Seno Lateral/complicaciones , Trombosis del Seno Lateral/diagnóstico por imagen , Trombosis del Seno Lateral/terapia , Masculino , Meningitis Bacterianas/complicaciones , Meningitis Bacterianas/tratamiento farmacológico , Meningitis Bacterianas/microbiología , Otitis Media con Derrame/terapia , Complicaciones Posoperatorias , Infecciones por Pseudomonas/complicaciones , Infecciones por Pseudomonas/tratamiento farmacológico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Succión , Tomografía Computarizada por Rayos X
8.
Int J Pediatr Otorhinolaryngol ; 46(1-2): 9-13, 1998 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-10190699

RESUMEN

Children with acute mastoiditis with periosteitis are conventionally hospitalized for parenteral antibiotics and/or surgical treatment. However, if possible, effective and safe outpatient treatment is desirable. During a 36-month period, outpatient parenteral antibiotic therapy (once daily i.m. ceftriaxone) was evaluated in 32 children with acute mastoiditis, with clinical evidence of periosteitis. Inclusion criteria included otomicroscopic evidence of acute otitis media (AOM), displacement of the pinna, retroauricular swelling, erythema and tenderness. The treatment consisted of wide myringotomy and administration of i.m. antibiotics. Daily visits, by a combined team of an otolaryngologist and pediatric infectious disease specialist, were considered essential. Fourteen children (43%) were treated initially in the hospital (and subsequently as outpatients) and 18 (57%) children were treated entirely as outpatients. Mean duration of outpatient treatment was 7 days (range: 4-10). The overall clinical cure rate was 96.8%. One child underwent simple mastoidectomy. No serious side effects were observed. Our data suggests that many children with acute mastoiditis with periosteitis can be managed successfully and safely as outpatients by a combined team of otolaryngologists and infectious disease specialists.


Asunto(s)
Atención Ambulatoria , Ceftriaxona/uso terapéutico , Cefalosporinas/uso terapéutico , Mastoiditis/tratamiento farmacológico , Mastoiditis/cirugía , Periostitis/tratamiento farmacológico , Periostitis/cirugía , Enfermedad Aguda , Preescolar , Femenino , Hospitalización , Humanos , Masculino , Apófisis Mastoides/cirugía , Factores de Tiempo , Resultado del Tratamiento , Membrana Timpánica/cirugía
9.
Int J Pediatr Otorhinolaryngol ; 68(11): 1435-9, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15488977

RESUMEN

UNLABELLED: Acute mastoiditis (AM) is an uncommon but serious complication of acute otitis media (AOM). In the pre-antibiotic era, AM was seen more frequently than it is today, but it was rare in infants. However, in the last two decades an increase in the incidence of AM in infancy has been reported in the literature. During the years 1990-2002, we treated 113 patients with 128 episodes of AM; of them, 24 were infants (median age 6 months; 18 males) who suffered from 26 episodes of AM. Twenty developed AM as a complication of their first episode of AOM. One of the four infants with a prior history of AOM suffered from common variable immunodeficiency. A significant increase in the incidence of AM in infants was recorded during the study period (P = 0.01). The most common presenting clinical signs were post-auricular swelling and fever >38 degrees C (77% and 77%, respectively, of all patients). Seventeen episodes of AM were not treated with prior antibiotics. Tympanocentesis was performed in all episodes of AM. Middle ear fluid culture was positive in 17 (65%) of the 26 AM episodes. The most common pathogens cultured were Streptococcus pneumoniae (10 infants, 58% of all pathogens, 3/10 intermediately susceptible to penicillin) followed by Streptococcus pyogenes (4, 23%), non-typable H. influenzae (2, 12%) and S. aureus (1, 6%). Temporal bone CT showed bone destruction in 14 patients; 3 infants had subperiosteal abscesses and 3 lateral sinus thrombosis. Ten infants underwent mastoid surgery due to non-resolution of symptoms and signs with antibiotic therapy. Eight underwent cortical mastoidectomy with two patients undergoing ventilation tube introduction only. The remainder of the infants healed with conservative treatment. CONCLUSIONS: (1) A significant increase in the incidence of AM in infants was recorded over the last decade, though a specific reason for this trend remains uncertain; (2) Most of the cases of AM followed the infant's initial AOM episode, and most of the infants had not received prior antibiotic therapy; (3) The clinical signs and symptoms of AM were more severe in infants than in older patients; (4) While S. pneumonia was the most common pathogen isolated in middle ear fluid cultures, the involvement of S. pyogenes in AM was higher than that reported in AOM.


Asunto(s)
Mastoiditis/complicaciones , Mastoiditis/terapia , Absceso/complicaciones , Enfermedad Aguda , Antibacterianos/uso terapéutico , Haemophilus influenzae/aislamiento & purificación , Humanos , Lactante , Israel , Masculino , Apófisis Mastoides/cirugía , Mastoiditis/diagnóstico , Mastoiditis/microbiología , Ventilación del Oído Medio , Enfermedades Orbitales/complicaciones , Otitis Media/complicaciones , Otitis Media/tratamiento farmacológico , Trombosis de los Senos Intracraneales/complicaciones , Staphylococcus aureus/aislamiento & purificación , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus pyogenes/aislamiento & purificación
10.
J Laryngol Otol ; 114(1): 41-6, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10789410

RESUMEN

Recent epidemiological research has raised the possibility of a connection between viral infection by the human papilloma virus (HPV) and the existence of squamous cell carcinoma of the oral cavity and oroharynx (SCCa). Some 60 subtypes have been identified to date, and specific subtypes are associated with lesions or infections at specific tissue sites. Twenty-three patients with SCCa of the oral cavity were studied for the presence of HPV in their tumours. HPV DNA (all type 16) was isolated from four specimens (17.3 per cent) using the Polymerase Chain Reaction (PCR) method. The four patients were all over age 50, and had advanced tumours (two T3 and two T4) that originated in the oropharynx. Our data supports other reports in the literature, demonstrating the presence of HPV DNA type 16 within cells from oropharyngeal SCCa. We conclude that the PCR method is a useful and reliable method for the detection of HPV DNA within tumour cells.


Asunto(s)
Carcinoma de Células Escamosas/virología , Neoplasias de la Boca/virología , Neoplasias Orofaríngeas/virología , Papillomaviridae/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Orofaringe/virología , Reacción en Cadena de la Polimerasa/métodos
11.
Ear Nose Throat J ; 75(12): 793-5, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8991230

RESUMEN

Cystic fibrosis (CF) is the most common lethal inherited disease in the white population. It is characterized by exocrine gland epithelia dysfunction, which leads to pulmonary and pancreatic insufficiency. Since the cloning of the CF gene in 1989 and the identification of the most common CF mutation (delta F508), more than 400 different mutations have been described. These mutations appear to contribute to the heterogeneity of the CF phenotype and several reports have speculated on the relationship between the most common CF mutations and the patient's clinical status. We report the case of a 21-year-old woman with longstanding chronic pansinusitis, nasal polyposis, chronic cough and severe nasal crusting. During a period of five years she had been followed by her otolaryngologist and pediatric pulmonologist. Sweat tests performed at the age of 17 and 18 were within normal limits and she underwent repeated conventional sinonasal procedures, with no improvement in her clinical status. On her present admission, sweat tests showed a 70 meq/l chloride concentration. The diagnosis of CF was then confirmed by DNA analysis and the patient was found to carry the 3849 + 10 kB C-->T mutation. The early detection of this newly recognized form of CF in adults as well as in children presenting with sinonasal symptoms is critical for life expectancy and quality.


Asunto(s)
Fibrosis Quística/genética , Mutación Puntual , Adulto , Fibrosis Quística/complicaciones , Femenino , Humanos , Klebsiella/aislamiento & purificación , Mucosa Nasal/microbiología , Sinusitis/complicaciones
12.
Ear Nose Throat J ; 80(8): 576-8, 580, 582 passim, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11523477

RESUMEN

Fungal involvement of the paranasal sinuses is frequently observed in the immunocompromised host, and it can become life-threatening if it is not diagnosed. Although the definitive diagnosis is made by tissue biopsy and culture, imaging is of vital importance in the clinical workup and in planning treatment. We present a case of fulminant ethmoidal sinusitis caused by Aspergillus flavus with orbital involvement in an immunocompromised patient. Standard computed tomography of the paranasal sinuses was complemented by the use of standardized orbital ultrasonography, which was able to identify the intraorbital extension. We discuss the role of standardized orbital ultrasonography as a complementary imaging modality in the diagnosis of fungal sinusitis and in the assessment of local extension. To the best of our knowledge, the role of SOU in diagnosing an orbital extension of a fungal infection of the paranasal sinuses has not been previously discussed in the literature.


Asunto(s)
Sinusitis del Etmoides/microbiología , Infecciones Fúngicas del Ojo/diagnóstico por imagen , Infecciones Fúngicas del Ojo/microbiología , Órbita/diagnóstico por imagen , Órbita/microbiología , Anciano , Humanos , Masculino , Ultrasonografía
15.
Phys Rev Lett ; 101(4): 043903, 2008 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-18764330

RESUMEN

Observation of surface-plasmon phenomena that are dependent upon the handedness of the circularly polarized incident light (spin) is presented. The polarization-dependent near-field intensity distribution obtained in our experiment is attributed to the presence of a geometric phase arising from the interaction of light with an anisotropic and inhomogeneous nanoscale structure. A near-field vortex surface mode with a spin-dependent topological charge was obtained in a plasmonic microcavity. The remarkable phenomenon of polarization-sensitive focusing in a plasmonic structure was also demonstrated.

16.
J Laryngol Otol ; 121(8): e12, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17498323

RESUMEN

The occipitotemporal vein (OTV) courses over the temporal lobe, connecting the superficial middle cerebral vein and the transverse sinus. This vein is rarely identifiable on computerized tomography (CT) scans and a large amount of contrast is needed to identify such a relatively small vessel. We present a 12-month-old male with acute coalescent mastoiditis and a subperiosteal abscess. An epidural abscess was suspected on pre-operative CT scan. No abscess was found on surgery. Based on the surgical finding, we determined that this misdiagnosis was due to a vascular variant, the occipitotemporal vein (vein of Labbe) that masqueraded as an abscess on the CT scan. Recognition of the vein of Labbe on CT scan is therefore essential for the appropriate management of otological and neurotological disease.


Asunto(s)
Venas Cerebrales/diagnóstico por imagen , Absceso Epidural/diagnóstico , Lóbulo Temporal/irrigación sanguínea , Errores Diagnósticos , Absceso Epidural/complicaciones , Humanos , Lactante , Masculino , Mastoiditis/complicaciones , Tomografía Computarizada por Rayos X
17.
Anal Biochem ; 225(1): 127-34, 1995 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-7778763

RESUMEN

A novel homogeneous immunoassay requiring only one incubation step, and applicable in principle to the determination of low- as well as high-molecular-weight substances, has been developed. The method is based on (a) photooxidation by singlet oxygen (1O2) of a fluorescent substrate (1,3-diphenylisobenzofuran, DPBF) embedded in unilamellar vesicles on the surface of which antibody to the analyte antigen is covalently attached (DPBF-immunoliposomes); (b) generation of singlet oxygen, upon illumination, by a chromophore (erythrosine) covalently attached to an antibody (Ab*) or antigen (Ag*); (c) formation of a "sandwich"- or "competition"-type complex whereupon the singlet oxygen-generating chromophore conjugate (Ab* or Ag*) and immunoliposome-embedded DPBF are brought into close proximity. Competition- and sandwich-type model assay systems for the detection of protein antigens and viruses were investigated. The detection range with protein antigens in competition- and sandwich-type assays was three (10(-10) - 10(-7) M) and two (10(-10) - 10(-8) M) orders of magnitude, respectively. With poliovirus using a sandwich-type assay, the detection range was 10(2) - 10(6) plaque-forming units per milliliter (pfu/ml).


Asunto(s)
Técnica del Anticuerpo Fluorescente , Animales , Anticuerpos , Reacciones Antígeno-Anticuerpo , Benzofuranos , Eritrosina , Cabras/inmunología , Inmunoglobulina G , Indicadores y Reactivos , Cinética , Liposomas , Peso Molecular , Oxidación-Reducción , Oxígeno , Fotólisis , Conejos/inmunología , Oxígeno Singlete
18.
Pediatr Radiol ; 24(3): 180-1, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7936793

RESUMEN

Calcification in untreated lymphoma is exceedingly rare. We report an unusual case of Burkitt's lymphoma, detected on plain radiographs and by ultrasonographic and CT examination.


Asunto(s)
Linfoma de Burkitt/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Abdomen/diagnóstico por imagen , Linfoma de Burkitt/complicaciones , Calcinosis/etiología , Niño , Cara/diagnóstico por imagen , Femenino , Humanos , Radiografía Abdominal , Tomografía Computarizada por Rayos X , Ultrasonografía
19.
Clin Orthop Relat Res ; (170): 286-95, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7127959

RESUMEN

The radioactive tracer microsphere method is applicable to the study of the hemodynamics of bone. As observed previously by others, areas of predominantly cancellous bone produce higher blood flow measurements than do areas of predominantly cortical bone. Bone containing fatty marrow has lower blood flow rates than does bone containing hematopoietic marrow. Blood flow to the femoral neck was the greatest measured (26.74 +/- 1.95 ml/min/100 gm), while the diaphyseal region was the area with the lowest flow (4.67 +/- 0.46 ml/min/100 gm). There was no significant difference between consecutive measurements using up to five differently labeled radioactive microspheres. This enabled observations of the effects of an experimental procedure on bone blood flow in the same animal. Additionally, there was no statistically significant differences between regional blood flows measured 40 days apart in the same animal. Bone blood flow measurements were slightly lower in anesthetized than in conscious dogs. The RTM method is the one most suitable for the estimation of bone blood flow under either acute or chronic conditions.


Asunto(s)
Fémur/irrigación sanguínea , Radioisótopos , Anestesia , Animales , Perros , Microesferas , Flujo Sanguíneo Regional
20.
Indian J Otolaryngol Head Neck Surg ; 52(2): 182-4, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23119668

RESUMEN

Desmoid tumors are histologically benign fibrous neoplasms arising from the musculoaponeurotic structures throughout the body. There is similar biological behaviour between benign fibrous proliferations and fibrosarcoma. These neoplasms have the tendency to locally invade and erode adjacent muscular tissue and bone. Within the head and neck area they also tend to encase vital structures. We present a case of a 28-year-old white female with a five-month history of a painful mass in her left posterior cervical triangle who was treated by excisional biopsy of the lesion with preservation of the accessory nerve and post-operative radiation. The histopathologic characteristics of desmoid tumors and treatment of these lesions are also reviewed.

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