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1.
Phys Rev Lett ; 126(24): 240502, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213945

RESUMO

Continuous-time quantum walks can be used to solve the spatial search problem, which is an essential component for many quantum algorithms that run quadratically faster than their classical counterpart, in O(sqrt[n]) time for n entries. However, the capability of models found in nature is largely unexplored-e.g., in one dimension only nearest-neighbor Hamiltonians have been considered so far, for which the quadratic speedup does not exist. Here, we prove that optimal spatial search, namely with O(sqrt[n]) run time and high fidelity, is possible in one-dimensional spin chains with long-range interactions that decay as 1/r^{α} with distance r. In particular, near unit fidelity is achieved for α≈1 and, in the limit n→∞, we find a continuous transition from a region where optimal spatial search does exist (α<1.5) to where it does not (α>1.5). Numerically, we show that spatial search is robust to dephasing noise and that, for reasonable chain lengths, α≲1.2 should be sufficient to demonstrate optimal spatial search experimentally with near unit fidelity.

2.
Pituitary ; 23(6): 641-647, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32857272

RESUMO

PURPOSE: Moderate hyperprolactinaemia (2-5 times upper limit of normal) occurring in a patient with a normal pituitary MRI is generally considered to be due to a lesion below the level of detection of the MRI scanner assuming macroprolactin and stress have been excluded. Most patients with mild-to-moderate hyperprolactinaemia and a normal MRI respond to dopamine agonist therapy. We present the rare case of a patient who had prolactin elevation typical of a prolactin-secreting pituitary macroadenoma,with a normal cranial MRI, and in whom the prolactin rose further with dopamine agonist treatment. Subsequent investigations revealed ectopic hyperprolactinaemia to a uterine tumor resembling ovarian sex cord tumor (UTROSCT) which resolved following tumor resection. Although mostly considered to be benign, the UTROSCT recurred with recurrent hyperprolactinaemia and intraabdominal metastases. METHODS: We have systematically and critically reviewed existing literature relating to ectopic hyperprolactinaemia in general and UTROCST specifically. RESULTS: Fewer than 80 cases of UTROSCTs have been reported globally of which about 23% have shown malignant behaviour. There are fewer than 10 cases of paraneoplastic hyperprolactinaemia originating from uterine neoplasms including one other case of ectopic hyperprolactinaemia to a UTROSCT. CONCLUSIONS: Our case demonstrates the importance of screening for extracranial hyperprolactinaemia in the context of: (1) substantially raised prolactin (10× ULN) and (2) normal cranial MRI assuming macroprolactin has been excluded. The majority of extracranial ectopic prolactin-secreting tumors occur in the reproductive organs.


Assuntos
Hiperprolactinemia/patologia , Neoplasias Uterinas/patologia , Adulto , Agonistas de Dopamina/uso terapêutico , Feminino , Humanos , Hiperprolactinemia/tratamento farmacológico , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Prolactinoma/tratamento farmacológico , Prolactinoma/patologia , Neoplasias Uterinas/tratamento farmacológico
3.
Liver Int ; 38(9): 1592-1601, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29461676

RESUMO

BACKGROUND: Liver volume (LV) can be non-invasively determined from the analysis of computed tomography (CT) images, and in patients with acute liver injury (ALI) or failure (ALF), it can reflect the balance of structural collapse with hepatic regeneration. We examined its relation to cause of liver injury, measures of liver function and histopathological findings, and utility in prediction of complications and mortality. METHODS: Two hundred and seventy-three patients with ALF/ALI admitted to a specialist intensive care unit were studied. One hundred and ninety-nine patients (73%) had non-acetaminophen (NA) aetiologies and 74 (27%) had acetaminophen-induced disease. LV and proportion of predicted LV (PLV%) were determined from admission CT imaging. RESULTS: LV and PLV% showed marked variation when aetiologic groups were compared (P < .0001), including loss in cases with indeterminate cause (LV 939 cm3 [IQR 680-1259], PLV% 56% [42-84]) and increase in Budd-Chiari syndrome (1891 cm3 [1601-2094], 121% [111-131]). Progression to high-grade encephalopathy was more common with smaller LV and PLV. A < 1000 cm3 threshold identified NA patients who later developed it with 93% (95%CI 83-98) specificity and odds ratio 10.6 (3.3-34.5) at median 5 days prior to onset, and risk of death in those with NA-drug-induced (DILI) or indeterminate disease with 91% (71-99) specificity and 63% (50-75) sensitivity. CONCLUSION: In patients with ALF/ALI, LV shows marked variation by the cause of disease, and in prognostic importance. In indeterminate and DILI cases, loss of volume to <1000 cm3 may indicate irreversible liver injury and regenerative failure and serve as an early clinical predictor for the development of high-grade encephalopathy and death.


Assuntos
Encefalopatia Hepática/mortalidade , Falência Hepática Aguda/diagnóstico por imagem , Falência Hepática Aguda/etiologia , Fígado/patologia , Tomografia Computadorizada por Raios X , Acetaminofen/efeitos adversos , Adulto , Síndrome de Budd-Chiari/complicações , Técnicas de Apoio para a Decisão , Progressão da Doença , Feminino , Encefalopatia Hepática/etiologia , Humanos , Fígado/diagnóstico por imagem , Transplante de Fígado/efeitos adversos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Sensibilidade e Especificidade , Análise de Sobrevida
4.
Clin Chem ; 63(12): 1836-1846, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28904054

RESUMO

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare malignancy, with an annual incidence of 1 or 2 cases per million. Biochemical diagnosis is challenging because up to two-thirds of the carcinomas are biochemically silent, resulting from de facto enzyme deficiencies in steroid hormone biosynthesis. Urine steroid profiling by GC-MS is an effective diagnostic test for ACC because of its capacity to detect and quantify the increased metabolites of steroid pathway synthetic intermediates. Corresponding serum assays for most steroid pathway intermediates are usually unavailable because of low demand or lack of immunoassay specificity. Serum steroid analysis by LC-MS/MS is increasingly replacing immunoassay, in particular for steroids most subject to cross-reaction. METHODS: We developed an LC-MS/MS method for the measurement of serum androstenedione, corticosterone, cortisol, cortisone, 11-deoxycorticosterone, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone sulfate, pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone, and testosterone. Assay value in discriminating ACC from other adrenal lesions (phaeochromocytoma/paraganglioma, cortisol-producing adenoma, and lesions demonstrating no hormonal excess) was then investigated. RESULTS: In ACC cases, between 4 and 7 steroids were increased (median = 6), and in the non-ACC groups, up to 2 steroids were increased. 11-Deoxycortisol was markedly increased in all cases of ACC. All steroids except testosterone in males and corticosterone and cortisone in both sexes were of use in discriminating ACC from non-ACC adrenal lesions. CONCLUSIONS: Serum steroid paneling by LC-MS/MS is useful for diagnosing ACC by combining the measurement of steroid hormones and their precursors in a single analysis.


Assuntos
Neoplasias do Córtex Suprarrenal/sangue , Carcinoma Adrenocortical/sangue , Esteroides/sangue , Espectrometria de Massas em Tandem/métodos , Neoplasias do Córtex Suprarrenal/diagnóstico , Carcinoma Adrenocortical/diagnóstico , Adulto , Idoso , Cromatografia Líquida/métodos , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade
6.
Surg Open Sci ; 14: 75-80, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37519329

RESUMO

Background: Despite technical advances, day surgery still accounts for <1 % of adrenal procedures. We investigated feasibility and safety of same day adrenalectomy (SDA). Methods: Between We recruited 30 patients with primary hyperaldosteronism (PHA) or Cushing's syndrome (CS) into a prospective matched, single centre cohort study to evaluate the impact of exposure to a same day discharge pathway (SDA cohort; n = 10) or inpatient adrenalectomy (PIPA cohort; n = 20). We compared results to a matched cohort (n = 40) from our prospective in-patient adrenalectomy registry (RIPA cohort). Results: Mean age was 51.3 ± 8.5 years, with 43 % female, 3.3 % ASA I and 96.7 % ASA II. Lesion size was 17 ± 9 mm (range 5-40 mm). 80 % of patients presented with PHA. The predefined primary endpoint (discharge on same calendar day without major complications, emergency presentation or readmission) was achieved in 100 % of SDA, but none of the in-patients (χ2 = 57; p < 0.0001). The secondary endpoint (discharge within 23 h of surgery without major complications, emergency presentation or readmission) was achieved in 100 % of SDA, 90 % of PIPA (n.s.), 33 % of RIPA (33 %; χ2 = 14.6 p < 0.001), and 51.5 % of IPA patients (χ2 = 8.5 p < 0.01). Combining SDA and PIPA cohorts, 93.3 % of treatment episodes met widely used (WHO, United States) definitions of day surgery as completion of the hospital care episode within 23 h. Patients admitted for SDA were highly satisfied (100 %). Conclusion: Same day discharge after adrenalectomy is feasible, safe, and well-perceived in appropriately selected patients with PHA and Cushing's syndrome.

7.
Med ; 3(12): 824-826, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36495863

RESUMO

Monkeypox (Mpox) is a global health emergency. Yeh et al. analyze tandem repeats and linkage disequilibrium in monkeypox virus (MPXV) sequences from the 2022 pandemic to determine the virus evolution, showing that these are useful tools to monitor and track phylogenetic dynamics and recombination of MPXV.


Assuntos
Mpox , Humanos , Filogenia , Mpox/epidemiologia , Monkeypox virus/genética , Surtos de Doenças
9.
Nat Rev Endocrinol ; 17(7): 435-444, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34021277

RESUMO

Approximately 20% of patients diagnosed with a phaeochromocytoma or paraganglioma carry a germline mutation in one of the succinate dehydrogenase (SDHx) genes (SDHA, SDHB, SDHC and SDHD), which encode the four subunits of the SDH enzyme. When a pathogenic SDHx mutation is identified in an affected patient, genetic counselling is proposed for first-degree relatives. Optimal initial evaluation and follow-up of people who are asymptomatic but might carry SDHx mutations have not yet been agreed. Thus, we established an international consensus algorithm of clinical, biochemical and imaging screening at diagnosis and during surveillance for both adults and children. An international panel of 29 experts from 12 countries was assembled, and the Delphi method was used to reach a consensus on 41 statements. This Consensus Statement covers a range of topics, including age of first genetic testing, appropriate biochemical and imaging tests for initial tumour screening and follow-up, screening for rare SDHx-related tumours and management of elderly people who have an SDHx mutation. This Consensus Statement focuses on the management of asymptomatic SDHx mutation carriers and provides clinicians with much-needed guidance. The standardization of practice will enable prospective studies in the near future.


Assuntos
Testes Genéticos/normas , Monitorização Fisiológica/normas , Succinato Desidrogenase/genética , Adulto , Idoso , Algoritmos , Doenças Assintomáticas , Criança , Consenso , Triagem de Portadores Genéticos/métodos , Triagem de Portadores Genéticos/normas , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Internacionalidade , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Monitorização Fisiológica/métodos
10.
Clin Res Hepatol Gastroenterol ; 44(2): 181-188, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31255533

RESUMO

BACKGROUND AND AIMS: Portal cavernoma associated cholangiopathy (PCC) is an uncommon disease in western countries. We describe our experience in seven patients with PCC, in particular the endoscopic management. We describe the mode of presentation, frequent symptoms and the outcome of different treatment modalities of patients with symptomatic PCC. METHODS: Prospectively maintained database was reviewed at a large tertiary referral unit in London, UK. Data included therapeutic interventions, outcomes and complications. RESULTS: Seven patients with PCC were followed for a median of 87 months [interquartile range (IQR), 62-107.5]. Causes of EHPVO included (hypercoagulable status, n=2, peritoneal tuberculosis n=1, neonatal sepsis, n=1, idiopathic, n=3). Acute cholangitis constituted the most recurring complications in all patients during the disease course. Endoscopic intervention was deemed required in all patients for biliary decompression, with 5 out 7 patients managed with repeat endoscopic sessions, (total=23 ERCPs). Surgical portal decompression (meso-caval shunt) was successfully performed in one patient and another patient underwent liver transplantation for decompensated liver cirrhosis. When endoscopic intervention was indicated, a fully covered self expanding metal stent (FcSEMS) provided a longer "symptoms free" period when compared to plastic stent, 7.5 (IQR, 4.75-18.25) and 4 (IQR, 3.5-7) months respectively, P=0.03. Bile duct bleeding occurred in two patients during ERCP procedure, however none of the patients had spontaneous haemobilia. Both patients were successfully treated by FcSEMS. CONCLUSION: Acute cholangitis is a common presentation and recurrent complication during the disease course. Spontaneous haemobilia seems to be uncommon, however it is a significant potential hazard during endoscopic intervention. Insertion of FcSEMS may remodel choledochal varices and provide a longer "symptoms free" period compared to plastic stents.


Assuntos
Colangite/etiologia , Veia Porta , Trombose/complicações , Adolescente , Adulto , Idoso , Doenças dos Ductos Biliares , Colangite/diagnóstico , Colangite/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Trombose/diagnóstico , Trombose/cirurgia , Adulto Jovem
11.
Eur Radiol ; 19(7): 1763-71, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19190913

RESUMO

To review our experience of placement of a mushroom-cage gastrostomy tube (Entristar, Tyco Healthcare, Mansfield, MA), using radiological guidance, in patients with amyotrophic lateral sclerosis (ALS). All procedures were performed under local anaesthesia without sedation. Complications were recorded as peri-procedural, early (<24 h), late (>24 h), major or minor. Deaths were recorded as related to the underlying ALS or secondary to radiological-inserted gastrostomy (RIG) placement. Replacement RIG tube rate was recorded. Over a 5-year period RIG tubes were placed in 104 patients with ALS (male n = 52, female n = 52), with a median age of 62 years (range 34-86 years). All procedures were technically successful. Of the RIG procedures, 21/104 (20.2%) were performed with respiratory support. The 30-day mortality rate was 7/104 (6.7%); no patient died as a result of the procedure. There were 23/104 (22.1%) complications overall; 20/104 (19.2%) were minor and 3/104 (2.9%) major, requiring surgery (n = 2) and radiological-guided abscess drainage (n = 1). A median interval between replacement RIG procedures in 20/104 (19.2%) patients was 141.5 days (range 43-537 days). A mushroom-cage RIG tube may be safely and effectively inserted in a 'one-step' radiological procedure and may replace endoscopic-inserted gastrostomy tubes in the nutritional management of ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico por imagem , Esclerose Lateral Amiotrófica/cirurgia , Gastrostomia/instrumentação , Gastrostomia/métodos , Implantação de Prótese/métodos , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Radiografia , Resultado do Tratamento
12.
Br J Radiol ; 92(1099): 20180864, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30845823

RESUMO

Percutaneous microwave ablation of liver tumours is a well-established technique that has been proven to be effective in the curative and palliative treatment of small volume primary and secondary liver tumours. Microwave ablation is designed to achieve larger areas of necrosis compared to radiofrequency ablation and has a good safety profile among liver tumour treatments. Mortality is unreported and major complications are rare. Knowledge of potential complications is essential for interventional radiologists performing liver ablation in order to reduce patient morbidity. The aim of this review is to illustrate major complications post microwave ablation in a pictorial format as well as a discussion on how best to avoid these complications.


Assuntos
Técnicas de Ablação/métodos , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/prevenção & controle , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Micro-Ondas , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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