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1.
Mol Cancer Ther ; 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691846

RESUMEN

The treatment of primary central nervous system (CNS) tumors is challenging due to the blood-brain barrier and complex mutational profiles, which is associated with low survival rates. However, recent studies have identified common mutations in gliomas (IDH-WT and mutant, WHO grades II-IV; with grade IV tumors referred to as glioblastomas; GBMs). These mutations drive epigenetic changes, leading to promoter methylation at the NAPRT gene locus, which encodes an enzyme involved in generating NAD+. Importantly, NAPRT-silencing introduces a therapeutic vulnerability to inhibitors targeting another NAD+ biogenesis enzyme, NAMPT, rationalizing a treatment for these malignancies. Multiple systemically-administered NAMPTis have been developed and tested in clinical trials, but dose-limiting toxicities-including bone marrow suppression and retinal toxicity-have limited their efficacy. Here, we report a novel approach for the treatment of NAPRT-silenced GBMs using nanoparticle-encapsulated (NP) NAMPT inhibitors (NAMPTis) administered by convection-enhanced delivery (CED). We demonstrate that GMX1778 (a NAMPTi) can be formulated in degradable polymer NPs with retention of potency for NAMPT inhibition and anticancer activity in vitro, plus sustained drug release in vitro and in vivo. Direct injection of these drugs via CED into the brain is associated with reduced retinal toxicity compared with systemic administration. Finally, we show that CED of NP-encapsulated GMX1778 to NAPRT-silenced intracranial GBM xenografts in mice exhibit significant tumor growth delay and extends survival. These data support an approach to treat gliomas harboring defects in NAD+ metabolism using CED of NP-encapsulated NAMPTis to greatly improve the therapeutic index and treatment efficacy for this class of drugs.

2.
Eat Disord ; : 1-15, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38686640

RESUMEN

Community evidence indicates high eating disorder (ED) and comorbid symptom severity among LGBTQ+ compared to cisgender heterosexual (CH) individuals. Little is known about such disparities in ED treatment samples, especially in outpatient treatment. We aimed to descriptively characterize and investigate baseline group differences in symptom severity between LGBTQ+ and CH ED outpatients at treatment intake. Data from 60 (22.3%) LGBTQ+ and 209 (77.7%) CH ED outpatients were used to examine: (1) demographic and diagnostic differences; (2) differences in ED, depressive, and emotion dysregulation symptoms. Objectives were tested using Fisher-Freeman-Halton exact and independent samples t-tests, and analyses of covariance adjusted for age and diagnosis, respectively. Most LGBTQ+ outpatients were bisexual (55.2%), and 6.5% identified as transgender and non-binary. LGBTQ+ outpatients presented to treatment at younger ages (Mean Difference [MD] = -3.39, p = .016) and reported more severe depressive symptoms (MD = 5.73, p = .004) than CH patients, but endorsed similar ED symptom and emotion dysregulation severity. Groups did not differ in other demographic or diagnostic characteristics. LGBTQ+ individuals may develop more severe depression and similarly severe EDs at earlier ages but seek outpatient care sooner than CH peers. Managing depressive symptoms may be particularly important for LGBTQ+ ED patients.

3.
EClinicalMedicine ; 69: 102453, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38544795

RESUMEN

Ovarian immature teratoma (IT) is a rare neoplasm comprising ∼3% of ovarian cancers, occurring primarily in young females. Management presents several challenges, including those with elevated serum alpha-fetoprotein, potential confusion regarding pathology interpretation, and paucity of data to support decision-making. MaGIC (https://magicconsortium.com/) is an interdisciplinary international consortium of GCT experts from multiple subspecialties, with members receiving frequent queries regarding IT patient management. With evidence from published literature where available, we summarise consensus management of such patients. Given lack of published data, controversy in certain areas remains. The most obvious variance in practice is between paediatric and adult teams, despite very similar outcomes. Paediatric teams typically employ a surgery-only approach, whereas in adult practice, all patients, except those with stage IA, grade 1 (low-grade) tumours, still generally receive adjuvant chemotherapy. Given the rarity of ovarian IT and lack of published data, discussion with GCT experts and/or national advisory panels is recommended.

4.
Exp Physiol ; 109(2): 214-226, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38050866

RESUMEN

Autonomic dysfunction is a common complication of type 2 diabetes mellitus (T2DM). However, the character of dysfunction varies in different reports. Differences in measurement methodology and complications might have influenced the inconsistent results. We sought to evaluate comprehensively the relationship between abnormal glucose metabolism and autonomic function at rest and the response to exercise in healthy individuals and T2DM patients. We hypothesized that both sympathetic and parasympathetic indices would decrease with the progression of abnormal glucose metabolism in individuals with few complications related to high sympathetic tone. Twenty healthy individuals and 11 T2DM patients without clinically evident cardiovascular disease other than controlled hypertension were examined. Resting muscle sympathetic nerve activity (MSNA), heart rate variability, spontaneous cardiovagal baroreflex sensitivity (CBRS), sympathetic baroreflex sensitivity and the MSNA response to handgrip exercise were measured. Resting MSNA was lower in patients with T2DM than in healthy control subjects (P = 0.011). Resting MSNA was negatively correlated with haemoglobin A1c in all subjects (R = -0.45, P = 0.024). The parasympathetic components of heart rate variability and CBRS were negatively correlated with glycaemic/insulin indices in all subjects and even in the control group only (all, P < 0.05). In all subjects, the MSNA response to exercise was positively correlated with fasting blood glucose (R = 0.69, P < 0.001). Resting sympathetic activity and parasympathetic modulation of heart rate were decreased in relationship to abnormal glucose metabolism. Meanwhile, the sympathetic responses to handgrip were preserved in diabetics. The responses were correlated with glucose/insulin parameters throughout diabetic and control subjects. These results suggest the importance of a comprehensive assessment of autonomic function in T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2 , Insulinas , Humanos , Fuerza de la Mano , Presión Sanguínea/fisiología , Sistema Nervioso Simpático/fisiología , Barorreflejo/fisiología , Frecuencia Cardíaca/fisiología , Glucosa , Músculo Esquelético/fisiología
5.
Pediatr Dev Pathol ; 27(3): 260-265, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38098239

RESUMEN

Wilms tumor (WT) is the commonest cause of renal cancer in children. In Europe, a diagnosis is made for most cases on typical clinical and radiological findings, prior to pre-operative chemotherapy. Here, we describe a case of a young boy presenting with a large abdominal tumor, associated with raised serum alpha-fetoprotein (AFP) levels at diagnosis. Given the atypical features present, a biopsy was taken, and histology was consistent with WT, showing triphasic WT, with epithelial, stromal, and blastemal elements present, and positive WT1 and CD56 immunohistochemical staining. During pre-operative chemotherapy, serial serum AFP measurements showed further increases, despite a radiological response, before a subsequent fall to normal following nephrectomy. The resection specimen was comprised of ~55% and ~45% stromal and epithelial elements, respectively, with no anaplasia, but immunohistochemistry using AFP staining revealed positive mucinous intestinal epithelium, consistent with the serum AFP observations. The lack of correlation between tumor response and serum AFP levels in this case highlights a more general clinical unmet need to identify WT-specific circulating tumor markers.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Renales , Tumor de Wilms , alfa-Fetoproteínas , Humanos , Tumor de Wilms/diagnóstico , Tumor de Wilms/patología , Tumor de Wilms/sangre , alfa-Fetoproteínas/análisis , alfa-Fetoproteínas/metabolismo , Masculino , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/análisis , Neoplasias Renales/diagnóstico , Neoplasias Renales/patología , Neoplasias Renales/sangre , Nefrectomía
7.
Br J Cancer ; 129(9): 1451-1461, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37789102

RESUMEN

BACKGROUND: MiR-371~373 and miR-302/367 cluster over-expression occurs in all malignant germ cell tumours (GCTs), regardless of age (paediatric/adult), site (gonadal/extragonadal), or subtype [seminoma, yolk sac tumour (YST), embryonal carcinoma (EC)]. Six of eight microRNAs from these clusters contain the seed sequence 'AAGUGC', determining mRNA targeting. Here we sought to identify the significance of these observations by targeting these microRNAs functionally. METHODS: We targeted miR-371~373 and/or miR-302/367 clusters in malignant GCT cell lines, using CRISPR-Cas9, gapmer primary miR-302/367 transcript inhibition, and peptide nucleic acid (PNA) or locked nucleic acid (LNA)-DNA inhibition targeting miR-302a-d-3p, and undertook relevant functional assays. RESULTS: MiR-302/367 cluster microRNAs made the largest contribution to AAGUGC seed abundance in malignant GCT cells, regardless of subtype (seminoma/YST/EC). Following the unsuccessful use of CRISPR-Cas9, gapmer, and PNA systems, LNA-DNA-based targeting resulted in growth inhibition in seminoma and YST cells. This was associated with the de-repression of multiple mRNAs targeted by AAGUGC seed-containing microRNAs, with pathway analysis confirming predominant disruption of Rho-GTPase signalling, vesicle organisation/transport, and cell cycle regulation, findings corroborated in clinical samples. Further LNA-DNA inhibitor studies confirmed direct cell cycle effects, with an increase of cells in G0/G1-phase and a decrease in S-phase. CONCLUSION: Targeting of specific miR-371~373 and miR-302/367 microRNAs in malignant GCTs demonstrated their functional significance, with growth inhibition mediated through cell cycle disruption.


Asunto(s)
MicroARNs , Neoplasias de Células Germinales y Embrionarias , Seminoma , Neoplasias Testiculares , Masculino , Adulto , Humanos , Niño , MicroARNs/genética , Seminoma/genética , Neoplasias Testiculares/patología , Ciclo Celular , ADN
9.
Cureus ; 15(9): e44593, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37667785

RESUMEN

The pubic branches of the inferior epigastric and obturator arteries are subject to injury from pelvic trauma or surgery within the retropubic space. Such injuries can result in severe internal hemorrhage that can lead to hemodynamic instability if not adequately controlled. Due to their anatomical proximity and anastomosis, it is critical to determine which artery is hemorrhaging in order to provide accurate embolization. In the presented case, a geriatric patient suffered a fall from standing height that resulted in bilateral and multiple pelvic fractures. CT angiography of the abdomen demonstrated active left-sided pelvic hemorrhage and a resultant 10 cm anterior extraperitoneal hematoma, likely exacerbated by existing anticoagulant usage. Urgent embolization of the inferior epigastric artery was performed in addition to multiple transfusions. The patient recovered without any procedural complications and was later discharged for rehabilitation.

10.
Cureus ; 15(8): e44328, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37649927

RESUMEN

Chronic pancreatitis has been shown to cause various pathologies, such as biliary strictures and pancreatic malignancies, which can in turn result in biliary outlet obstruction. However, a pancreatic calculus itself resulting in biliary obstruction has been far less observed. The patient in question had a documented history of chronic alcoholism and received a cholecystectomy decades prior to the onset of cholestatic symptoms. Cholangiography demonstrated no indication of biliary stricture formation, nor was there radiological evidence of pancreatic pseudocyst or malignant formation. CT evidence across a decade of time established a storyline of pancreatic calculi formation, migration, and resultant biliary obstruction. Subsequent endoscopic sphincterectomy, pancreatic calculi removal, and biliary tree stent placement resulted in laboratory value normalization and clinical symptom resolution.

11.
Cureus ; 15(5): e38396, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37265886

RESUMEN

Agenesis or dysgenesis of the corpus callosum may occur due to ischemic, toxic, traumatic, or another insult to the fetus in the first trimester. Occasionally, such a malformation is associated with an interhemispheric cyst, among other central nervous system anomalies. Holoprosencephaly tends to mimic this radiographic presentation, which is where key imaging findings are helpful to differentiate between these entities. We present a 56-year-old male patient who was found to have a monoventricle, corpus callosum agenesis, interhemispheric cyst, and a Dandy-Walker malformation. The patient presented with a right acetabular fracture with computed tomography (CT) of the brain revealing the congenital brain abnormalities. The patient's past medical history was notable for a seizure disorder identified during early adulthood. The CT scan of the head revealed a large monoventricle with an associated midline dorsal interhemispheric cyst and a Dandy-Walker malformation. The absence of both the corpus callosum and septum pellucidum was noted, with the presence of a monoventricle, leading to an initial differential of holoprosencephaly. Further review of the findings suggested instead a rare congenital presentation consisting of corpus callosum agenesis and an interhemispheric cyst. This case highlights a unique radiographic presentation of multiple brain anomalies, rarely presented in non-pediatric literature, which may help determine appropriate surgical and medical management for similarly affected adult individuals.

12.
Resuscitation ; 190: 109875, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37327848

RESUMEN

BACKGROUND: Single-center studies have identified risk factors for peri-intubation cardiac arrest in the emergency department (ED). The study objective was to generate validity evidence from a more diverse, multicenter cohort of patients. METHODS: We completed a retrospective cohort study of 1200 paediatric patients who underwent tracheal intubation in eight academic paediatric EDs (150 per ED). The exposure variables were 6 previously studied high-risk criteria for peri-intubation arrest: (1) persistent hypoxemia despite supplemental oxygen, (2) persistent hypotension, (3) concern for cardiac dysfunction, (4) post-return of spontaneous circulation (ROSC), (5) severe metabolic acidosis (pH < 7.1), and (6) status asthmaticus. The primary outcome was peri-intubation cardiac arrest. Secondary outcomes included extracorporeal membrane oxygenation (ECMO) cannulation and in-hospital mortality. We compared all outcomes between patients that met one or more versus no high-risk criteria, using generalized linear mixed models. RESULTS: Of the 1,200 paediatric patients, 332 (27.7%) met at least one of 6 high-risk criteria. Of these, 29 (8.7%) suffered peri-intubation arrest compared to zero arrests in patients meeting none of the criteria. On adjusted analysis, meeting at least one high-risk criterion was associated with all 3 outcomes - peri-intubation arrest (AOR 75.7, 95% CI 9.7-592.6), ECMO (AOR 7.1, 95% CI 2.3-22.3) and mortality (AOR 3.4, 95% 1.9-6.2). Four of 6 criteria were independently associated with peri-intubation arrest: persistent hypoxemia despite supplemental oxygen, persistent hypotension, concern for cardiac dysfunction, and post-ROSC. CONCLUSIONS: In a multicenter study, we confirmed that meeting at least one high-risk criterion was associated with paediatric peri-intubation cardiac arrest and patient mortality.


Asunto(s)
Paro Cardíaco , Hipotensión , Humanos , Niño , Estudios Retrospectivos , Intubación Intratraqueal/efectos adversos , Paro Cardíaco/etiología , Paro Cardíaco/terapia , Hipoxia/complicaciones , Hipotensión/etiología , Oxígeno
13.
Noncoding RNA Res ; 8(3): 413-425, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37305178

RESUMEN

Background: Wilms tumour (WT) is caused by aberrant embryonic kidney development and associated with dysregulated expression of short, non-protein-coding RNAs termed microRNAs (miRNAs). At present, there is no reliable circulating biomarker of WT, and this remains an urgent unmet clinical need. Such biomarkers may assist diagnosis, subtyping/prognostication, and disease-monitoring. Here, we established the list of dysregulated circulating miRNAs in WT from the existing published literature. Methods: Regardless of publication date, PubMed, Scopus, Web-of-Science, and Wiley online library databases were searched for English/French studies on WT circulating miRNAs. The PRISMA-compliant search was registered in PROSPERO. The QUADAS tool measured retained article quality. The meta-analysis assessed the sensitivity and specificity of miRNAs for WT diagnosis. Results: Qualitative analysis included 280 samples (172 WT patients; 108 healthy controls) from five of 450 published articles. The study uncovered 301 dysregulated miRNAs (144 up-regulated, 143 down-regulated, 14 conflicting). The pooled sensitivity, specificity, and AUC of the 49 significantly dysregulated microRNAs from two studies was 0.67 [0.62; 0.73], 0.95 [0.92; 0.96] and 0.77 [0.73; 0.81] respectively, indicating a stronger diagnostic potential for WT. Conclusions: Circulating miRNAs show promise for WT diagnosis and prognosis. More research is needed to confirm these findings and determine associations with tumour stage/subtype. Prospero registration number: CRD42022301597.

14.
Sci Rep ; 13(1): 10558, 2023 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-37386046

RESUMEN

Circulating miR-371a-3p has excellent performance in the detection of viable (non-teratoma) germ cell tumor (GCT) pre-orchiectomy; however, its ability to detect occult disease is understudied. To refine the serum miR-371a-3p assay in the minimal residual disease setting we compared performance of raw (Cq) and normalized (∆Cq, RQ) values from prior assays, and validated interlaboratory concordance by aliquot swapping. Revised assay performance was determined in a cohort of 32 patients suspected of occult retroperitoneal disease. Assay superiority was determined by comparing resulting receiver-operator characteristic (ROC) curves using the Delong method. Pairwise t-tests were used to test for interlaboratory concordance. Performance was comparable when thresholding based on raw Cq vs. normalized values. Interlaboratory concordance of miR-371a-3p was high, but reference genes miR-30b-5p and cel-miR-39-3p were discordant. Introduction of an indeterminate range of Cq 28-35 with a repeat run for any indeterminate improved assay accuracy from 0.84 to 0.92 in a group of patients suspected of occult GCT. We recommend that serum miR-371a-3p test protocols are updated to (a) utilize threshold-based approaches using raw Cq values, (b) continue to include an endogenous (e.g., miR-30b-5p) and exogenous non-human spike-in (e.g., cel-miR-39-3p) microRNA for quality control, and (c) to re-run any sample with an indeterminate result.


Asunto(s)
MicroARNs , Neoplasias de Células Germinales y Embrionarias , Teratoma , Humanos , MicroARNs/genética , Neoplasias de Células Germinales y Embrionarias/diagnóstico , Neoplasias de Células Germinales y Embrionarias/genética , Bioensayo , Pruebas Hematológicas
15.
Opt Express ; 31(13): 20651-20664, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37381184

RESUMEN

Persistent wideband radio frequency (RF) surveillance and spectral analysis is increasingly important, driven by the proliferation of wireless communication and RADAR technology. However, conventional electronic approaches are limited by the ∼1 GHz bandwidth of real-time analog-to-digital converters (ADCs). While faster ADCs exist, high data rates prohibit continuous operation, limiting these approaches to acquiring short snapshots of the RF spectrum. In this work, we introduce an optical RF spectrum analyzer designed for continuous, wideband operation. Our approach encodes the RF spectrum as sidebands on an optical carrier and relies on a speckle spectrometer to measure these sidebands. To achieve the resolution and update rate required for RF analysis, we use Rayleigh backscattering in single-mode fiber to rapidly generate wavelength-dependent speckle patterns with MHz-level spectral correlation. We also introduce a dual-resolution scheme to mitigate the trade-off between resolution, bandwidth, and measurement rate. This optimized spectrometer design enables continuous, wideband (15 GHz) RF spectral analysis with MHz-level resolution and a fast update rate of 385 kHz. The entire system is constructed using fiber-coupled off-the-shelf-components, providing a powerful new approach for wideband RF detection and monitoring.

16.
Br J Haematol ; 202(5): 985-994, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37357529

RESUMEN

Anaplastic large-cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by the oncogenic anaplastic lymphoma kinase (ALK), accounting for approximately 15% of all paediatric non-Hodgkin lymphoma. Patients with central nervous system (CNS) relapse are particularly difficult to treat with a 3-year overall survival of 49% and a median survival of 23.5 months. The second-generation ALK inhibitor brigatinib shows superior penetration of the blood-brain barrier unlike the first-generation drug crizotinib and has shown promising results in ALK+ non-small-cell lung cancer. However, the benefits of brigatinib in treating aggressive paediatric ALK+ ALCL are largely unknown. We established a patient-derived xenograft (PDX) resource from ALK+ ALCL patients at or before CNS relapse serving as models to facilitate the development of future therapies. We show in vivo that brigatinib is effective in inducing the remission of PDX models of crizotinib-resistant (ALK C1156Y, TP53 loss) ALCL and furthermore that it is superior to crizotinib as a second-line approach to the treatment of a standard chemotherapy relapsed/refractory ALCL PDX pointing to brigatinib as a future therapeutic option.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Linfoma Anaplásico de Células Grandes , Niño , Humanos , Quinasa de Linfoma Anaplásico , Crizotinib/farmacología , Crizotinib/uso terapéutico , Proteínas Tirosina Quinasas Receptoras/uso terapéutico , Linfoma Anaplásico de Células Grandes/tratamiento farmacológico , Linfoma Anaplásico de Células Grandes/patología , Xenoinjertos , Neoplasias Pulmonares/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Compuestos Organofosforados/farmacología , Compuestos Organofosforados/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico
18.
Pediatr Blood Cancer ; 70(8): e30426, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37243320

RESUMEN

BACKGROUND/OBJECTIVES: Surgery is the mainstay of therapy for children with ovarian immature teratoma (IT), whereas adults receive adjuvant chemotherapy, except those with stage-I, grade-1 disease. In Brazil, children with metastatic ovarian IT received postoperative chemotherapy. This practice variation allowed evaluation of the value of chemotherapy, by comparison of Brazilian patients with those in the United States and United Kingdom. DESIGN/METHODS: From the Malignant Germ Cell International Consortium data commons, data on ovarian IT patients from two recently added Brazilian trials (TCG-99/TCG-2008) were compared with data from US/UK (INT-0106/GC-2) trials. Primary outcome measure was event-free (EFS) and overall survival (OS). RESULTS: Forty-two Brazilian patients were included (stage I: 27, stage II: 4, stage III: 8, stage IV: 3). Twenty-nine patients had surgery alone, whereas 13 patients received postoperative chemotherapy. The EFS and OS for entire cohort was 0.80 (95% CI: 0.64-0.89) and 0.97 (0.84-0.99). There was no difference in relapse risk based on stage, grade, or receipt of chemotherapy. Comparing the Brazilian cohort with 98 patients in US/UK cohort (stage I: 59, stage II: 12, stage III: 27), there was no difference in EFS and OS across all stages, despite 87% of stage II-IV Brazilian patients receiving postoperative chemotherapy compared with only 13% of US/UK patients. The EFS and OS for Brazilian compared with US/UK cohort was stage I: 88% versus 98% (p = .05), stage II-IV EFS: 67% versus 79% (p = .32), stage II-IV OS: 93% versus 97% (p = .44); amongst grade-3 patients, there was no difference in EFS or OS. CONCLUSION: Addition of postoperative chemotherapy did not improve outcome in children with ovarian IT, even at higher grade or stage, compared with surgery alone.


Asunto(s)
Neoplasias Ováricas , Teratoma , Adulto , Femenino , Humanos , Niño , Estados Unidos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/cirugía , Neoplasias Ováricas/patología , Teratoma/tratamiento farmacológico , Teratoma/patología , Quimioterapia Adyuvante
19.
Sci Rep ; 13(1): 5762, 2023 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-37031276

RESUMEN

Frequency shifting loops, consisting of a fiber optic ring cavity, a frequency modulator, and an amplifier to compensate for loss, enable high-speed frequency scanning with precise and easily controlled frequency steps. This platform is particularly attractive for applications in spectroscopy and optical ranging. However, amplified spontaneous emission noise accumulates due to the repeated amplification of light circulating in the cavity, limiting the frequency scanning range of existing frequency shifting loops (FSLs). Here, we introduce a cascaded approach which addresses this basic limitation. By cascading multiple FSLs in series with different frequency shifts we are able to dramatically increase the accessible scanning range. We present modeling showing the potential for this approach to enable scanning over ranges up to 1 THz-a tenfold increase compared with the state-of-the-art. Experimentally, we constructed a pair of cascaded FSLs capable of scanning a 200 GHz range with 100 MHz steps in 10 ms and used this platform to perform absorption spectroscopy measurements of an H13C14N cell. By increasing the operating bandwidth of FSLs, the cascaded approach introduced in this work could enable new applications requiring precise and high-speed frequency scanning.

20.
Res Sq ; 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36993198

RESUMEN

Circulating miR-371a-3p has excellent performance in the detection of viable (non-teratoma) GCT pre-orchiectomy; however, its ability to detect occult disease is understudied. To refine the serum miR-371a-3p assay in the minimal residual disease setting we compared performance of raw (Cq) and normalized (∆Cq, RQ) values from prior assays, and validated interlaboratory concordance by aliquot swapping. Revised assay performance was determined in a cohort of 32 patients suspected of occult retroperitoneal disease. Assay superiority was determined by comparing resulting receiver-operator characteristic (ROC) curves using the Delong method. Pairwise t-tests were used to test for interlaboratory concordance. Performance was comparable when thresholding based on raw Cq vs. normalized values. Interlaboratory concordance of miR-371a-3p was high, but reference genes miR-30b-5p and cel-miR-39-3p were discordant. Introduction of an indeterminate range of Cq 28-35 with a repeat run for any indeterminate improved assay accuracy from 0.84 to 0.92 in a group of patients suspected of occult GCT. We recommend that serum miR-371a-3p test protocols are updated to a) utilize threshold-based approaches using raw Cq values, b) continue to include an endogenous (e.g., miR-30b-5p) and exogenous non-human spike-in (e.g., cel-miR-39-3p) microRNA for quality control, and c) to re-run any sample with an indeterminate result.

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