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1.
Rev Sci Instrum ; 91(5): 054504, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32486713

RESUMEN

Microfabricated resonators play a crucial role in the development of quantum measurement, including future gravitational wave detectors. We use a micro-genetic algorithm and a finite element method to design a microresonator whose geometry is optimized to maximize the sub-Standard Quantum Limit (SQL) performance including lower thermal noise (TN) below the SQL, a broader sub-SQL region, and a sub-SQL region at lower frequencies. For the proposed design, we study the effects of different geometries of the mirror pad and cantilever microresonator on sub-SQL performance. We find that the maximum ratio of SQL to TN is increased, its frequency is decreased, and the sub-SQL range is increased by increasing the length of the microresonator cantilever, increasing the radius of the mirror pad, decreasing the width of the microresonator cantilever, and shifting the laser beam location from the mirror center. We also find that there exists a trade-off between the maximum ratio of SQL to TN and the sub-SQL bandwidth. The performance of this designed microresonator will allow it to serve as a test-bed for quantum non-demolition measurements and to open new regimes of precision measurement that are relevant for many practical sensing applications, including advanced gravitational wave detectors.

2.
Phys Rev Lett ; 120(23): 230502, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29932715

RESUMEN

Boson sampling is a well-defined task that is strongly believed to be intractable for classical computers, but can be efficiently solved by a specific quantum simulator. However, an outstanding problem for large-scale experimental boson sampling is the scalability. Here we report an experiment on boson sampling with photon loss, and demonstrate that boson sampling with a few photons lost can increase the sampling rate. Our experiment uses a quantum-dot-micropillar single-photon source demultiplexed into up to seven input ports of a 16×16 mode ultralow-loss photonic circuit, and we detect three-, four- and fivefold coincidence counts. We implement and validate lossy boson sampling with one and two photons lost, and obtain sampling rates of 187, 13.6, and 0.78 kHz for five-, six-, and seven-photon boson sampling with two photons lost, which is 9.4, 13.9, and 18.0 times faster than the standard boson sampling, respectively. Our experiment shows an approach to significantly enhance the sampling rate of multiphoton boson sampling.

4.
Kidney Int ; 71(10): 1044-53, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17361117

RESUMEN

Chronic renal disease is characterized by declining renal function, loss of intrinsic renal cells, and their replacement with fibrotic tissue. This study investigates apoptosis and its regulation in the context of chronic renal disease. RNA was extracted from renal biopsies from patients with various forms of chronic renal disease. Expression of genes of the Bcl-2 family, death receptor pathway, and growth factors were measured by reverse-transcription real-time polymerase chain reaction. Apoptosis was detected by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling technique. Tubulointerstitial apoptosis was positively associated with tubulointerstitial injury and renal dysfunction and increased 2.3-fold per unit (U) increase in transforming growth factor beta(1) (TGFbeta(1)) mRNA (P<0.05). Conversely, a 1 U increase in epidermal growth factor (EGF) mRNA was associated with a 47% decrease in tubulointerstitial apoptosis (P<0.05). Tubulointerstitial injury was correlated with increased TGFbeta(1) and tumour necrosis factor alpha (TNFalpha) mRNA (P<0.005) and decreased EGF mRNA (P<0.05). Additionally, for a 10 U decrease in the glomerular filtration rate there was an estimated increase of 5 and 10% in TGFbeta(1) and TNFalpha mRNA, respectively (P<0.05), whereas EGF mRNA decreased by an estimated 15% (P<0.005). Therefore dysregulation of cytokine/growth factor expression plays a central role in the progression of chronic renal disease through contribution to renal cell loss, tubulointerstitial injury, and renal dysfunction.


Asunto(s)
Apoptosis , Regulación de la Expresión Génica , Péptidos y Proteínas de Señalización Intercelular/genética , Enfermedades Renales/fisiopatología , Túbulos Renales/fisiopatología , Riñón/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/genética , Biomarcadores/sangre , Biopsia , Enfermedad Crónica , Factor de Crecimiento Epidérmico/genética , Femenino , Expresión Génica , Tasa de Filtración Glomerular , Humanos , Riñón/patología , Enfermedades Renales/complicaciones , Enfermedades Renales/genética , Enfermedades Renales/patología , Masculino , Persona de Mediana Edad , Proteinuria/etiología , ARN Mensajero/metabolismo , Factor de Crecimiento Transformador beta1/genética , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/genética
5.
Transplantation ; 72(11): 1826-9, 2001 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11740395

RESUMEN

Cyclosporine nephropathy (CyAN) is a major limiting factor in the otherwise successful widespread use of cyclosporine in solid organ transplant. Transforming growth factor-beta1 (TGF-beta1) has been implicated as an important fibrogenic cytokine in the development of this disease. TGF-beta-inducible gene-H3 (beta(ig)-H3) is a TGF-beta1- induced gene product, which acts as a marker for biologically active TGF-beta1. This study reports TGF-beta1 gene expression and beta(ig)-H3 tissue distribution in non-renal allograft CyAN. Renal tissue from nine patients who had developed CyAN after successful heart or heart-lung transplantation and from four kidneys removed for tumour were analyzed for TGF-beta1 gene expression beta(ig)-H3 protein with reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. TGF-beta1 gene expression was increased in CyAN compared to nephrectomy (P<0.0001). Beta(ig)-H3 protein expression was identified in distal convoluted tubular epithelium and parietal glomerular epithelium in CyAN, and not in nephrectomy samples. Expression of TGF-beta1 mRNA was significantly higher in renal tissue from patients not receiving angiotensin converting enzyme inhibitor (ACEI) therapy for hypertension (P<0.05). These findings support the hypothesis that TGF-beta1 is an important cytokine in the development of CyAN, independent of its role in chronic rejection in renal allografts.


Asunto(s)
Ciclosporina/efectos adversos , Proteínas de la Matriz Extracelular , Trasplante de Corazón , Trasplante de Corazón-Pulmón , Inmunosupresores/efectos adversos , Enfermedades Renales/inducido químicamente , Enfermedades Renales/metabolismo , Proteínas de Neoplasias/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Adulto , Humanos , Riñón/metabolismo , Túbulos Renales Distales/metabolismo , Persona de Mediana Edad , ARN Mensajero/metabolismo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta1
6.
J Am Soc Nephrol ; 10(3): 499-506, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10073600

RESUMEN

The majority of patients with rapidly progressive crescentic glomerulonephritis show histologic features of extensive necrosis and focal and segmental proliferation with fibrin production, but little or absent Ig deposition in the glomerulus. This subcategory of the disease, labeled "pauci-immune" glomerulonephritis, has recently been shown to be associated with the presence of antineutrophil cytoplasmic antibody in the patient's circulation (but not within the glomerulus). The absence of the effectors of humoral immunity at the site of renal injury led to this investigation of the contribution of cell-mediated immunity to the glomerular injury in this form of glomerulonephritis. In 15 patients presenting acutely with pauci-immune glomerulonephritis, CD3-positive T cells (3.7+/-2.5 [mean +/- SD] cells per glomerular cross section, [c/gcs]), CD45RO-positive T cells (2.7+/-1.9 c/cgs), macrophages (7.3+/-6.1 c/gcs), fibrin (3+), and endothelial-associated tissue factor were demonstrated to be prominent in glomeruli. These mediators were absent in a group of 12 patients with thin basement membrane disease and only occasionally observed in a group of eight patients with "humorally mediated"(noncrescentic) glomerulonephritis. Thus, in pauci-immune glomerulonephritis, there is the development of significant cell-mediated immunity with activated T cells, macrophages, tissue factor, and fibrin at the site of glomerular injury, suggesting that this glomerular disease is most likely a manifestation of T cell-directed cognate immune injury.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/análisis , Glomerulonefritis/inmunología , Glomerulonefritis/patología , Adulto , Anciano , Anciano de 80 o más Años , Formación de Anticuerpos , Biomarcadores/análisis , Biopsia , Técnicas de Cultivo , Progresión de la Enfermedad , Femenino , Humanos , Inmunidad Celular , Glomérulos Renales/patología , Masculino , Persona de Mediana Edad , Pronóstico , Valores de Referencia , Sensibilidad y Especificidad
7.
Pathology ; 31(4): 325-7, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10643001

RESUMEN

Infiltration of the kidney is commonly found in lymphoma, but acute renal failure arising from bilateral renal infiltration is uncommon. Primary renal lymphoma may occur and is usually of B-cell lineage. It is rare for patients with lymphoma to develop acute renal failure as their initial clinical presentation. Recently, an association between primary renal lymphoma and a second primary malignancy has been reported. We describe the first case of a renal T-cell-rich B-cell lymphoma presenting as acute renal failure, which was associated with a second primary pulmonary malignancy.


Asunto(s)
Lesión Renal Aguda/etiología , Adenocarcinoma/patología , Neoplasias Renales/patología , Neoplasias Pulmonares/patología , Linfoma de Células B/patología , Neoplasias Primarias Secundarias/patología , Linfocitos T/patología , Lesión Renal Aguda/patología , Lesión Renal Aguda/terapia , Adenocarcinoma/química , Adenocarcinoma/terapia , Anciano , Antígenos CD/análisis , Antígenos de Neoplasias/análisis , Femenino , Humanos , Técnicas para Inmunoenzimas , Neoplasias Renales/química , Neoplasias Renales/terapia , Neoplasias Pulmonares/química , Neoplasias Pulmonares/terapia , Linfoma de Células B/química , Linfoma de Células B/terapia , Neoplasias Primarias Secundarias/química , Neoplasias Primarias Secundarias/terapia
8.
Melanoma Res ; 8(5): 459-64, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9835460

RESUMEN

Between 6 and 14% of malignant melanomas have been reported to occur in a familial pattern. In this study 785 melanoma patients from the Victorian Melanoma Service and the private practice of a dermatologist were assessed for the total number of melanocytic naevi, the number of dysplastic naevi and other clinical characteristics categorized according to whether there was a family history of melanoma. It was found that the presence of 100 or more naevi, six or more dysplastic naevi and blue eyes in a patient with melanoma were significantly associated with a family history of melanoma. Patients with two or more family members with melanoma were significantly more likely to develop melanoma at a younger age and to develop multiple melanomas. This study concludes that large numbers of melanocytic naevi and dysplastic naevi in melanoma patients are useful characteristics in practice to identify patients at risk of familial occurrence of melanoma. Family members of these patients should receive a medical assessment for their pigmented lesions.


Asunto(s)
Melanoma/genética , Adulto , Australia/epidemiología , Síndrome del Nevo Displásico/epidemiología , Síndrome del Nevo Displásico/genética , Síndrome del Nevo Displásico/patología , Color del Ojo , Femenino , Humanos , Masculino , Melanoma/epidemiología , Melanoma/patología , Persona de Mediana Edad , Fenotipo
9.
Hum Pathol ; 29(11): 1246-9, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9824102

RESUMEN

Various well-documented renal lesions are associated with intravenous drug use; however, intraglomerular mesangial granulomas have not been previously described. We report three patients who developed an unusual granulomatous glomerulonephritis and interstitial nephritis after intravenous injection of oxycodone, derived from suppositories. Granulomas were seen in an intraglomerular mesangial and also interstitial location. In both sites, the granulomas were associated with filamentous material, presumably derived from a component of the suppositories. This material was periodic acid-Schiff-positive, but negative with Congo red and silver stains. Ultrastructurally, the filamentous material was seen within the mesangial granulomas and also in a subendothelial location, suggesting derivation from the circulation with subsequent transport across the basement membrane and accumulation in the mesangium, where a granulomatous reaction was elicited. All patients developed a degree of renal failure; two of the patients require hemodialysis 20 and 30 months after presentation.


Asunto(s)
Glomerulonefritis/etiología , Glomerulonefritis/patología , Trastornos Relacionados con Opioides/complicaciones , Oxicodona , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Femenino , Humanos , Masculino , Supositorios
11.
Clin Infect Dis ; 26(2): 359-64, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9502456

RESUMEN

We report a case of acute glomerulonephritis associated with acute Q fever. An abattoir worker with a nonspecific febrile illness and pneumonia and abnormal liver function test results developed hematuria, proteinuria, and acute renal failure that resolved with appropriate antimicrobial therapy. Renal biopsy demonstrated diffuse proliferative and exudative glomerulonephritis. Serological tests confirmed recent infection with Coxiella burnetii, with a fourfold rise in the titer of phase II antibody, positive phase II IgM antibody, and negative phase I antibody. Other known causes of glomerulonephritis were excluded. Most reports of renal complications of C. burnetii infection describe glomerulonephritis associated with endocarditis due to chronic Q fever. Renal involvement in patients with acute C. burnetii infection has been rarely described. Glomerulonephritis should be recognized as a complication of acute C. burnetii infection and endocarditis due to chronic Q fever.


Asunto(s)
Glomerulonefritis/complicaciones , Fiebre Q/complicaciones , Enfermedad Aguda , Adulto , Glomerulonefritis/inmunología , Glomerulonefritis/microbiología , Glomerulonefritis/fisiopatología , Humanos , Masculino , Fiebre Q/inmunología , Fiebre Q/microbiología , Fiebre Q/fisiopatología
14.
J Rheumatol ; 24(3): 598-600, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9058673

RESUMEN

Inflammatory vasculopathy and thrombotic thrombocytopenic purpura (TTP) are rare complications of scleroderma. We report a 54-year-old woman with limited cutaneous scleroderma who developed medium size and small vessel vasculitis. Inflammatory changes of medium size muscular arteries presented as ovarian vasculitis and mononeuritis multiplex, while arteriolar involvement presented as TTP with associated central nervous system involvement. In addition, possible noninflammatory involvement of small muscular arteries was expressed as Raynaud's phenomenon.


Asunto(s)
Púrpura Trombocitopénica Trombótica/complicaciones , Esclerodermia Sistémica/complicaciones , Vasculitis/etiología , Femenino , Humanos , Persona de Mediana Edad , Vasculitis/complicaciones
15.
Australas J Dermatol ; 38(1): 12-4, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9046646

RESUMEN

A Spitz naevus is a benign melanocytic tumour that may histologically resemble a malignant melanoma. Data was retrospectively gathered from patients who attended the Victorian Melanoma Service to determine the prevalence of Spitz naevi pathologically misdiagnosed as melanoma. Assessment of the clinical characteristics of these patients was also performed and compared to those with correctly diagnosed melanoma. It was found that 6.5% of all melanomas referred were in fact Spitz naevi and that Spitz naevi represented the majority of pathologically misdiagnosed melanomas. The Spitz naevi were more likely to be on the lower extremities and were no average, considerably smaller than the melanomas. Patients with Spitz naevi were more likely to be younger, female, have fewer dysplastic naevi and have brown eyes. One hundred per cent of the Spitz naevi were brought to the attention of the initial doctor by the patient compared to 72% of the melanomas. This study concludes that Spitz naevi that are pathologically misdiagnosed as melanomas retain the clinical characteristics of other Spitz naevi and that greater clinicopathological communication may reduce the frequency of diagnostic error.


Asunto(s)
Errores Diagnósticos , Melanoma/diagnóstico , Nevo de Células Epitelioides y Fusiformes/diagnóstico , Enfermedades de la Piel/diagnóstico , Distribución de Chi-Cuadrado , Intervalos de Confianza , Diagnóstico Diferencial , Errores Diagnósticos/estadística & datos numéricos , Femenino , Humanos , Masculino , Melanoma/patología , Nevo de Células Epitelioides y Fusiformes/patología , Prevalencia , Estudios Retrospectivos , Enfermedades de la Piel/patología
19.
Histopathology ; 24(4): 377-9, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8045527

RESUMEN

Two primary sino-nasal melanomas are presented which were characterized by their botryoid growth pattern and myxoid stroma. These polypoid tumours contained small amounts of melanin and only focal areas of epithelioid cells. An in situ component was present in both of the tumours. Malignant melanoma should be considered when confronted by a myxoid tumour (with or without melanin) in the sino-nasal region. These tumours are widely infiltrative, and there is no evidence to suggest that they will behave any differently from conventional, non-botryoid, non-myxoid sino-nasal melanomas.


Asunto(s)
Melanoma/patología , Neoplasias Nasales/patología , Neoplasias de los Senos Paranasales/patología , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Melanoma/cirugía , Persona de Mediana Edad , Neoplasias Nasales/cirugía , Neoplasias de los Senos Paranasales/cirugía
20.
Stroke ; 24(6): 899-902, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8506563

RESUMEN

BACKGROUND AND PURPOSE: Systemic giant cell arteritis causing cerebellar infarction due to intracranial arteritis of the anterior inferior cerebellar artery has not been previously reported. We report this infrequent occurrence and discuss the differential diagnosis. CASE DESCRIPTION: An 85-year-old woman was admitted with a 2-week history of episodic ataxia, unilateral headaches, and vomiting. She had a history of atrial fibrillation and breast carcinoma. Her mental state was initially normal, and there were right-sided cerebellar signs. An ejection systolic murmur was heard, and peripheral pulses were palpable. A postmortem examination revealed cerebellar infarction due to giant cell arteritis of the anterior inferior cerebellar artery and basilar arteries. Systemic giant cell arteritis was also present. CONCLUSIONS: Giant cell arteritis is a systemic disorder that can infrequently involve intracranial vessels, including the basilar, vertebral, and anterior cerebellar arteries. Cerebellar infarction secondary to the arteritis may occur. The distribution and size of intracranial vessel involvement is distinct from isolated cranial angiitis.


Asunto(s)
Arteritis/complicaciones , Infarto Cerebral/etiología , Anciano , Arteritis/patología , Arteria Basilar/patología , Cerebelo/irrigación sanguínea , Infarto Cerebral/patología , Femenino , Células Gigantes , Soplos Cardíacos/complicaciones , Humanos , Células de Purkinje/patología
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