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1.
Exp Eye Res ; 218: 109024, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35271830

RESUMO

Type 2 idiopathic macular telangiectasia (MacTel-2) is a progressive adult-onset macular disease associated with bilateral perifoveal vascular changes, Muller cell degeneration and increased blood-retinal barrier permeability. The pathophysiological mechanisms of MacTel-2 remain unclear, however it was previously reported that anti-retinal antibodies in MacTel-2 patients are a significant feature of the disease. In this study, we aimed to compare the prevalence of anti-retinal antibodies in patients MacTel-2, healthy controls and patients with other retinal diseases. MacTel-2 patients diagnosed with multimodal imaging were enrolled and their disease severities were graded using spectral-domain optical coherence tomography. For comparison, patients with age-related macular degeneration (AMD), inherited retinal diseases (IRDs) or no retinal disease (healthy controls) were recruited as controls. Blood serum samples were screened for immunoglobulin G anti-retinal antibodies by western blotting, followed by densitometry analysis. Odds ratios (OR) with 95% confidence intervals (CI) were calculated and p < 0.05 considered statistically significant. Overall, anti-retinal antibody-positive cases were older (64 ± 15 vs 53 ± 17 years, p < 0.001) and females were more likely to develop anti-retinal antibodies (OR: 2.41, CI: 1.12-5.18). The frequency of anti-retinal antibody detection in MacTel-2 patients (n = 42, 36%) was not significantly different from healthy controls (n = 52, 25%) or IRD patients (n = 18, 25%) and the majority of MacTel-2 patients had no anti-retinal antibodies. In contrast, the frequency of anti-retinal antibody detection was significantly higher in patients with AMD (n = 15, 73%, p < 0.001). The lack of a greater anti-retinal antibody frequency or specificity in the MacTel-2 cohort suggests that antibody mediated immunological mechanisms may play a less significant role in MacTel-2 disease pathogenesis.


Assuntos
Retinopatia Diabética , Degeneração Macular , Telangiectasia Retiniana , Adulto , Retinopatia Diabética/patologia , Feminino , Humanos , Imunoglobulina G , Degeneração Macular/patologia , Retina/patologia , Telangiectasia Retiniana/diagnóstico , Telangiectasia Retiniana/patologia , Tomografia de Coerência Óptica/métodos
2.
Ann Hematol ; 101(8): 1689-1701, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35488900

RESUMO

This phase 1b study evaluated glasdegib (100 mg once daily) + azacitidine in adults with newly diagnosed acute myeloid leukemia (AML), higher-risk myelodysplastic syndromes (MDS), or chronic myelomonocytic leukemia (CMML) who were ineligible for intensive chemotherapy. Of 72 patients enrolled, 12 were in a lead-in safety cohort (LIC) and 60 were in the AML and MDS (including CMML) expansion cohorts. In the LIC, the safety profile of glasdegib + azacitidine was determined to be consistent with those of glasdegib or azacitidine alone, with no evidence of drug-drug interaction. In the expansion cohort, the most frequently (≥ 10%) reported non-hematologic Grade ≥ 3 treatment-emergent adverse events were decreased appetite, electrocardiogram QT prolongation, and hypertension in the AML cohort and sepsis, diarrhea, hypotension, pneumonia, and hyperglycemia in the MDS cohort. Overall response rates in the AML and MDS cohorts were 30.0% and 33.3%, respectively; 47.4% and 46.7% of patients who were transfusion dependent at baseline achieved independence. Median overall survival (95% confidence interval) was 9.2 (6.2-14.0) months and 15.8 (9.3-21.9) months, respectively, and response was associated with molecular mutation clearance. Glasdegib + azacitidine in patients with newly diagnosed AML or MDS demonstrated an acceptable safety profile and preliminary evidence of clinical benefits.Trial registration: ClinicalTrials.gov NCT02367456.


Assuntos
Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Adulto , Azacitidina/efeitos adversos , Benzimidazóis/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Compostos de Fenilureia/efeitos adversos , Medição de Risco , Resultado do Tratamento
3.
Ann Hematol ; 100(5): 1181-1194, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33740113

RESUMO

This analysis from the phase II BRIGHT AML 1003 trial reports the long-term efficacy and safety of glasdegib + low-dose cytarabine (LDAC) in patients with acute myeloid leukemia ineligible for intensive chemotherapy. The multicenter, open-label study randomized (2:1) patients to receive glasdegib + LDAC (de novo, n = 38; secondary acute myeloid leukemia, n = 40) or LDAC alone (de novo, n = 18; secondary acute myeloid leukemia, n = 20). At the time of analysis, 90% of patients had died, with the longest follow-up since randomization 36 months. The combination of glasdegib and LDAC conferred superior overall survival (OS) versus LDAC alone; hazard ratio (HR) 0.495; (95% confidence interval [CI] 0.325-0.752); p = 0.0004; median OS was 8.3 versus 4.3 months. Improvement in OS was consistent across cytogenetic risk groups. In a post-hoc subgroup analysis, a survival trend with glasdegib + LDAC was observed in patients with de novo acute myeloid leukemia (HR 0.720; 95% CI 0.395-1.312; p = 0.14; median OS 6.6 vs 4.3 months) and secondary acute myeloid leukemia (HR 0.287; 95% CI 0.151-0.548; p < 0.0001; median OS 9.1 vs 4.1 months). The incidence of adverse events in the glasdegib + LDAC arm decreased after 90 days' therapy: 83.7% versus 98.7% during the first 90 days. Glasdegib + LDAC versus LDAC alone continued to demonstrate superior OS in patients with acute myeloid leukemia; the clinical benefit with glasdegib + LDAC was particularly prominent in patients with secondary acute myeloid leukemia. ClinicalTrials.gov identifier: NCT01546038.


Assuntos
Antineoplásicos/uso terapêutico , Benzimidazóis/uso terapêutico , Citarabina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzimidazóis/administração & dosagem , Citarabina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Análise de Sobrevida , Resultado do Tratamento
4.
Exp Eye Res ; 198: 108154, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32712181

RESUMO

Astrocytes are critical for the maintenance of retinal ganglion cell (RGC) axonal function and viability, and form a key component of the functional neurovascular unit. Recently, we described the quantitative properties of astrocytes in relation to the capillary distributions in optic nerve laminar regions. Here, we provide a quantitative analysis of astrocytes and RGC axons in longitudinal sections of optic nerve tissue. Histological and immunocytochemical techniques are used to demonstrate the density of astrocytes, RGC axons and glia-neuron ratios across the pre laminar, lamina cribrosa and post laminar compartments of the optic nerve head (ONH). A study of human, pig, horse and rat optic nerves was performed and comparisons are made between species. This study demonstrates that the distribution of astrocytes correlates closely with the density of axonal processes, in accordance with the functional requirement of different regions of the ganglion cell axon. There was a consistency of glia-neuron ratios in the majority of laminar compartments, except for the human and rat prelaminar regions, which demonstrated lower ratios of astrocyte to axonal processes. The distribution of astrocytes may reflect a functional susceptibility to development of disease in the prelaminar region of the optic nerve. Interspecies comparison at the lamina cribrosa showed strikingly consistent glia-neuron ratios. Collectively, our findings suggest there may be a critical ratio of glia to neuron needed to maintain healthy cellular physiology across different laminar compartments of the optic nerve, with particular importance for the health of the lamina cribrosa region. It is possible that, in disease processes, the glia-neuron relationships across the different laminar compartments may be perturbed and this may be relevant for the development of glaucoma. Emerging technologies may further aid our understanding in how the physiology of optic nerve tissue cellular structure may be affected by changes to ONH characteristics and elevated intraocular pressure induced damage. Such findings may also permit the early identification of RGC axonal injury by identifying quantifiable changes in structural tissue architecture when pathophysiological pathways predominate.


Assuntos
Astrócitos/patologia , Glaucoma/diagnóstico , Neuroglia/patologia , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Células Ganglionares da Retina/patologia , Adulto , Animais , Capilares/patologia , Doença , Feminino , Cavalos , Humanos , Masculino , Pessoa de Meia-Idade , Ratos , Suínos , Adulto Jovem
5.
Health Res Policy Syst ; 18(1): 97, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854722

RESUMO

BACKGROUND: Social, behavioural and community engagement (SBCE) interventions are essential for global maternal, newborn and child health (MNCH) strategies. Past efforts to synthesise research on SBCE interventions identified a need for clear priorities to guide future research. WHO led an exercise to identify global research priorities for SBCE interventions to improve MNCH. METHODS: We adapted the Child Health and Nutrition Research Initiative method and combined quantitative and qualitative methods to determine MNCH SBCE intervention research priorities applicable across different contexts. Using online surveys and meetings, researchers and programme experts proposed up to three research priorities and scored the compiled priorities against four criteria - health and social impact, equity, feasibility, and overall importance. Priorities were then ranked by score. A group of 29 experts finalised the top 10 research priorities for each of maternal, newborn or child health and a cross-cutting area. RESULTS: A total of 310 experts proposed 867 research priorities, which were consolidated into 444 priorities and scored by 280 experts. Top maternal and newborn health priorities focused on research to improve the delivery of SBCE interventions that strengthen self-care/family care practices and care-seeking behaviour. Child health priorities focused on the delivery of SBCE interventions, emphasising determinants of service utilisation and breastfeeding and nutrition practices. Cross-cutting MNCH priorities highlighted the need for better integration of SBCE into facility-based and community-based health services. CONCLUSIONS: Achieving global targets for MNCH requires increased investment in SBCE interventions that build capacities of individuals, families and communities as agents of their own health. Findings from this exercise provide guidance to prioritise investments and ensure that they are best directed to achieve global objectives. Stakeholders are encouraged to use these priorities to guide future research investments and to adapt them for country programmes by engaging with national level stakeholders.


Assuntos
Saúde da Criança , Serviços de Saúde Materna , Criança , Feminino , Saúde Global , Prioridades em Saúde , Humanos , Saúde do Lactente , Recém-Nascido , Saúde Materna , Gravidez , Pesquisa
6.
Future Oncol ; 15(31): 3531-3545, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31516032

RESUMO

Glasdegib, an oral Hedgehog pathway inhibitor, has been associated with significantly improved survival when combined with low-dose cytarabine in patients with untreated acute myeloid leukemia (AML) who were unsuitable for intensive chemotherapy, when compared with low-dose cytarabine alone. BRIGHT AML 1019 (NCT03416179) comprises two independently powered Phase III, randomized (1:1), double-blind global trials evaluating oral glasdegib 100 mg once daily or placebo plus one of two standard chemotherapy regimens in adults with untreated AML. The intensive trial combines glasdegib/placebo with cytarabine and daunorubicin (7 + 3), while the nonintensive trial combines glasdegib/placebo with azacitidine. The primary end point of both studies is overall survival. Secondary end points include response, time to and duration of response, event-free survival, safety, patient-reported outcomes and pharmacokinetics. Trial registration number: ClinicalTrials.gov identifier: NCT03416179.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos Clínicos , Leucemia Mieloide Aguda/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzimidazóis/administração & dosagem , Feminino , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/etiologia , Masculino , Compostos de Fenilureia/administração & dosagem , Projetos de Pesquisa
7.
Am J Hematol ; 93(11): 1301-1310, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30074259

RESUMO

Glasdegib is a Hedgehog pathway inhibitor. This ongoing, open-label, phase 2 study (NCT01546038) evaluated glasdegib plus cytarabine/daunorubicin in patients with untreated acute myeloid leukemia (AML) or high-risk myelodysplastic syndromes (MDS). Patients received glasdegib 100 mg orally, once daily in continuous 28-day cycles from day -3, with intravenous cytarabine 100 mg/m2 on days 1-7 and daunorubicin 60 mg/m2 on days 1-3. Patients in remission then received consolidation therapy (2-4 cycles of cytarabine 1 g/m2 twice daily on days 1, 3, 5 of each cycle), followed by maintenance glasdegib (maximum 6 cycles). Primary endpoint was complete remission (CR) in patients aged ≥55 years. Secondary endpoints included overall survival (OS), safety and outcome by mutational status. Patients had a median (range) age of 64.0 (27-75) years, 60.0% were male, and 84.5% were white. In 69 evaluable patients, 46.4% (80% confidence interval [CI]: 38.7-54.1) achieved investigator-reported CR. Among patients ≥55 years old (n = 60), 40.0% (80% CI 31.9-48.1) achieved CR. Among all 69 patients, median OS was 14.9 (80% CI 13.4-19.3) months, with 12-month survival probability 66.6% (80% CI 58.5-73.4). The most common treatment-related adverse events (≥50% patients) were diarrhea and nausea. There were no significant associations between mutational status (12 genes) and clinical response, suggesting potential benefit across diverse molecular profiles. Glasdegib plus cytarabine/daunorubicin was well tolerated and associated with clinical activity in patients with untreated AML or high-risk MDS. A randomized phase 3 trial of glasdegib in combination with chemotherapy (7 + 3 schedule) is ongoing.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzimidazóis/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia de Consolidação/métodos , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Feminino , Humanos , Leucemia Mieloide Aguda/complicações , Quimioterapia de Manutenção/métodos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Indução de Remissão/métodos , Resultado do Tratamento
8.
Cancer Sci ; 108(8): 1628-1633, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28556364

RESUMO

The hedgehog signaling pathway regulates multiple morphogenetic processes during embryogenesis. Aberrant activation of the hedgehog pathway signal transduction in adult tissues is associated with the pathogenesis of hematologic malignancies and solid tumors. We report findings from an open-label, multicenter phase I trial of the selective, small-molecule hedgehog signaling inhibitor glasdegib (PF-04449913) in Japanese patients with select advanced hematologic malignancies. Glasdegib was administered as once-daily oral doses (25, 50 and 100 mg) in 28-day cycles after a lead-in dose on Day -5. The primary objectives were to determine first-cycle dose-limiting toxicities, safety, vital signs and laboratory test abnormalities. Secondary objectives included evaluation of pharmacokinetics, pharmacodynamics and preliminary evidence of clinical activity of glasdegib. No dose-limiting toxicities were noted in the 13 patients in the present study. All patients experienced at least one treatment-emergent, all-causality adverse event. The most frequent treatment-related adverse events (observed in ≥3 patients) were dysgeusia (n = 9), muscle spasms (n = 5), alopecia, decreased appetite (n = 4 each), and increased blood creatinine phosphokinase, constipation and diarrhea (n = 3 each). Two deaths occurred during the study and were deemed not to be treatment-related due to disease progression. Glasdegib demonstrated dose-proportional pharmacokinetics, marked downregulation of the glioma-associated transcriptional regulator GLI1 expression in normal skin, and evidence of preliminary clinical activity, although data are limited. Glasdegib was safe and well tolerated across the dose levels tested. It is confirmed that the 100-mg dose is safe and tolerable in Japanese patients, and this dose level will be examined in the future clinical trial.


Assuntos
Antineoplásicos/administração & dosagem , Benzimidazóis/administração & dosagem , Neoplasias Hematológicas/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Proteína GLI1 em Dedos de Zinco/genética , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Benzimidazóis/efeitos adversos , Benzimidazóis/farmacologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hematológicas/genética , Humanos , Japão , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacologia , Resultado do Tratamento
9.
Lancet ; 386(10004): 1649-58, 2015 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-26231455

RESUMO

BACKGROUND: The thrombopoietin receptor agonist eltrombopag has been shown to be safe, tolerable, and effective for adults with chronic immune thrombocytopenia. We aimed to investigate the safety and efficacy of eltrombopag for children with chronic immune thrombocytopenia. METHODS: PETIT2 was a two part, randomised, multicentre, placebo-controlled study done at 38 centres in 12 countries (Argentina, Czech Republic, Germany, Hong Kong, Israel, Italy, Russia, Spain, Taiwan, Thailand, UK, and USA). Paediatric patients aged 1-17 years who had chronic immune thrombocytopenia and platelet counts less than 30 × 10(9) per L were randomly assigned (2:1) to receive eltrombopag or placebo. We stratified patients by age into three cohorts (patients aged 12-17 years, 6-11 years, and 1-5 years) before randomly entering them into a 13 week, double-blind period. Randomisation was done by the GlaxoSmithKline Registration and Medication Ordering System and both patients and study personnel were masked to treatment assignments. Patients who were allocated eltrombopag received tablets (except for those aged 1-5 years who received an oral suspension formulation) once per day for 13 weeks. Starting doses for patients aged 6-17 were based on bodyweight, and ethnic origin and ranged between 50 mg/day and 25 mg/day (starting dose for patients aged 1-5 years was 1·2 mg/kg/day or 0·8 mg/kg/day for east Asian patients). Patients who completed the double-blind period entered a 24 week open-label treatment period in which all patients received eltrombopag at either the starting dose (if they were formerly on placebo) or their established dose. The primary outcome was the proportion of patients achieving platelet counts of at least 50 × 10(9) per L in the absence of rescue therapy for 6 or more weeks from weeks 5 to 12 of the double-blind period. The intention-to-treat population included in the efficacy assessment consisted of all patients who were randomly assigned to one of the treatment groups, and the safety population included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT01520909. FINDINGS: Beginning in March 15, 2012, 92 patients were enrolled, and the trial was completed on Jan 2, 2014. 63 patients were assigned to receive eltrombopag and 29 were assigned to receive placebo. In the double-blind period, three patients discontinued treatment because of adverse events: two patients in the eltrombopag group withdrew because of increased liver aminotransferases and one in the placebo group withdrew because of abdominal haemorrhage. 25 (40%) patients who received eltrombopag compared with one (3%) patient who received placebo achieved the primary outcome of platelet counts of at least 50 × 10(9) per L for 6 of the last 8 weeks of the double-blind period (odds ratio 18·0, 95% CI, 2·3-140·9; p=0·0004). Responses were similar in all cohorts (eltrombopag vs placebo: 39% vs 10% for patients aged 12-17 years, 42% vs 0% for patients aged 6-11 years, and 36% vs 0% for patients aged 1-5 years). Proportionately fewer patients who received eltrombopag (23 [37%] of 63 patients) had WHO grades 1-4 bleeding at the end of the double-blind period than did those who received placebo (16 [55%] of 29 patients); grades 2-4 bleeding were similar (three [5%] patients who received eltrombopag vs two [7%] patients who received placebo). During the 24-week open-label treatment period, 70 [80%] of 87 patients achieved platelet counts of 50 × 10(9) per L or more at least once. Adverse events that occurred more frequently with eltrombopag than with placebo included nasopharyngitis (11 [17%] patients), rhinitis (10 [16%] patients), upper respiratory tract infection (7 [11%] patients), and cough (7 [11%] patients). Serious adverse events occurred in five (8%) patients who received eltrombopag and four (14%) who received placebo. Safety was consistent between the open-label and double-blind periods. No deaths, malignancies, or thromboses occurred during the trial. INTERPRETATION: Eltrombopag, which produced a sustained platelet response in 40% of patients with chronic immune thrombocytopenia, is a suitable therapeutic option for children with chronic symptomatic immune thrombocytopenia. We identified no new safety concerns and few patients discontinued treatment because of adverse events. FUNDING: GlaxoSmithKline.


Assuntos
Benzoatos/uso terapêutico , Hidrazinas/uso terapêutico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Pirazóis/uso terapêutico , Receptores de Trombopoetina/agonistas , Adolescente , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Criança , Pré-Escolar , Doença Crônica , Método Duplo-Cego , Feminino , Humanos , Hidrazinas/administração & dosagem , Hidrazinas/efeitos adversos , Lactente , Masculino , Contagem de Plaquetas , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Resultado do Tratamento
10.
Exp Eye Res ; 145: 341-346, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26892807

RESUMO

The relationship between structural characteristics of the optic nerve head and venous pulsations in the human eye remain unknown. Using photoplethysmographic techniques we investigated whether properties of the human retinal veins and their surrounding structures influence venous pulsation. 448 locations of venous pulsation were analysed from 26 normal human eyes. Green channel densitometry derived from video recordings of venous pulsations were used to generate a map of venous pulsation amplitudes along retinal veins. Optical coherence tomography was used to perform quantitative measurements of tissue characteristics at sites of high and low amplitude points as well as in a second analysis, at maximal amplitude pulsation sites from superior and inferior halves of the eyes. Structural characteristics measured included venous diameter, distance from pulsation point to cup margin, vessel length from pulsation point to vein exit, tissue thickness overlying vein, optic disc diameter and presence of a proximal arteriovenous crossing. Increasing venous pulsation amplitudes were associated with larger applied ophthalmodynamometry force, increasing venous diameter, and decreasing absolute cup margin distance (all p < 0.001). Increasing distance of maximal amplitude pulsation point to cup margin was associated with the presence of a proximal arteriovenous crossing, increasing venous diameter, and decreasing tissue depth (all p ≤ 0.001). Venous diameter and tissue depth alter venous compliance, which is likely to be a major factor determining sites of venous pulsation.


Assuntos
Disco Óptico/anatomia & histologia , Fluxo Pulsátil/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Veia Retiniana/fisiologia , Adulto , Idoso , Feminino , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/fisiopatologia , Disco Óptico/irrigação sanguínea , Tomografia de Coerência Óptica , Adulto Jovem
12.
Microvasc Res ; 100: 32-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25917012

RESUMO

Retinal capillary networks are critically linked to neuronal health and disease. The ability to perform accurate in vivo examination of human retinal capillary networks is therefore valuable for studying mechanisms that govern retinal homeostasis and retinal vascular diseases. Speckle variance optical coherence tomography (svOCT) is a non-invasive imaging technique that has the capacity to provide angiographic information about the retinal circulation. The application of this technology for studying human retinal capillary networks however has not been validated in a quantifiable manner. We use a custom-built svOCT device to qualitatively and quantitatively study the various capillary networks in the human perifovea. Capillary networks corresponding to the nerve fibre layer (NFL), the retinal ganglion cell/superficial inner plexiform layer (RGC/sIPL), the deep inner plexiform layer/superficial inner nuclear layer (dIPL/sINL) and the deep inner nuclear layer (dINL) are imaged in 9 normal human subjects. Measurements of capillary diameter and capillary density are made from each of these networks and results are compared to post-mortem histological data acquired with confocal scanning laser microscopy. Additionally, retinal capillary measurements from high-resolution fundus fluorescein angiogram (FA) are directly compared with svOCT images from 6 eyes. We demonstrate that svOCT images of capillary networks are morphologically comparable to microscopic images of histological specimens. Similar to histological images in svOCT images, the capillaries in the NFL network run parallel to the direction of RGC axons while capillaries in the dINL network comprise a planar configuration with multiple closed loops. Capillaries in remaining networks are convoluted with a complex three-dimensional architecture. We demonstrate that there is no significant difference in capillary density measurements between svOCT and histology images for all networks. Capillary diameter was significantly greater in svOCT images compared to histology for all networks. Capillary density measurements were also higher in svOCT compared to FA. The results of this study suggest that in vivo svOCT imaging allows accurate morphometric assessment of capillary networks in the human perifovea and may provide an improved ability to render microvascular detail compared to FA. Therefore, svOCT may have broad clinical applications in the study of human retinal physiology and disease. The difference in quantitative measurements between svOCT and histology may reflect dynamic variations in the retinal microcirculation and warrants further investigation.


Assuntos
Capilares/patologia , Imagem Óptica/métodos , Vasos Retinianos/patologia , Tomografia de Coerência Óptica , Adulto , Idoso , Capilares/fisiopatologia , Feminino , Angiofluoresceinografia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Microcirculação , Microscopia Confocal , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Vasos Retinianos/fisiopatologia , Adulto Jovem
13.
Exp Eye Res ; 121: 11-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24560677

RESUMO

Retinal ganglion cell (RGC) axonal structure and function in the optic nerve head (ONH) is predominantly supported by astrocytes and capillaries. There is good experimental evidence to demonstrate that RGC axons are perturbed in a non-uniform manner following ONH injury and it is likely that the pattern of RGC axonal modification bears some correlation with the quantitative properties of astrocytes and capillaries within laminar compartments. Although there have been some excellent topographic studies concerning glial and microvascular networks in the ONH our knowledge regarding the quantitative properties of these structures are limited. This report is an in-depth quantitative, structural analysis of astrocytes and capillaries in the pre laminar, lamina cribrosa and post laminar compartments of the ONH. 49 optic nerves from human (n = 10), pig (n = 12), horse (n = 6), rat (n = 11) and rabbit (n = 10) eyes are studied. Immunohistochemical and high-magnification confocal microscopy techniques are used to co-localise astrocytes, capillaries and nuclei in the mid-portion of the optic nerve. Quantitative methodology is used to determine the area occupied by astrocyte processes, microglia processes, nuclei density and the area occupied by capillaries in each laminar compartment. Comparisons are made within and between species. Relationships between ONH histomorphometry and astrocyte-capillary constitution are also explored. This study demonstrates that there are significant differences in the quantitative properties of capillaries and astrocytes between the laminar compartments of the human ONH. Astrocyte processes occupied the greatest area in the lamina cribrosa compartment of the human ONH implicating it as an area of great metabolic demands. Microglia were found to occupy only a small proportion of tissue in the rat, rabbit and pig optic nerve suggesting that the astrocyte is the predominant glia cell type in the optic nerve. This study also demonstrates that there is significant uniformity, with respect to astrocyte and capillary constitution, in the post laminar region of species with an unmyelinated anterior optic nerve. This implicates an important role served by oligodendrocytes and myelin in governing the structural characteristics of the post laminar optic nerve. Finally, this study demonstrates that eyes with similar lamina cribrosa structure do not necessarily share an identical cellular constitution with respect to astrocytes. The quantitative properties of astrocytes in the pre laminar and lamina cribrosa regions of the rat, which has a rudimentary lamina cribrosa with only a few collagenous beams, shared more similarities to the human eye than the pig or horse. The quantitative properties of astrocytes and capillaries in the laminar compartments of the ONH provide a basis for understanding the pathogenic mechanisms that are involved in diseases such as glaucoma and ischemic optic neuropathy. The findings in this study also provide valuable information about the distinct advantages of different animal models for studying human optic nerve diseases. Utilisation of structural data provided in this report together with emerging in vivo technology may potentially permit the early identification of RGC axonal injury by quantifying changes in ONH capillaries and astrocytes.


Assuntos
Astrócitos/citologia , Disco Óptico/irrigação sanguínea , Nervo Óptico/citologia , Adulto , Animais , Astrócitos/metabolismo , Axônios , Capilares/anatomia & histologia , Fator VII/metabolismo , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Proteína Glial Fibrilar Ácida/metabolismo , Cavalos , Humanos , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Nervo Óptico/metabolismo , Coelhos , Ratos , Ratos Endogâmicos BN , Células Ganglionares da Retina/citologia , Sus scrofa , Adulto Jovem
14.
Trop Med Infect Dis ; 9(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38393123

RESUMO

In Indonesia, the implementation of tuberculosis (TB) contact investigation is limited, with low detection rates. We report the yield of and risk factors for TB disease and infection for household contacts (HHCs) investigated using chest X-ray (CXR) screening. We identified HHCs aged five years and above of bacteriologically confirmed index cases from 2018 to 2022 in Yogyakarta City and Kulon Progo. All HHCs were offered screening for TB symptoms; TB infection testing with either tuberculin skin testing or interferon gamma release assay; and referral for CXR. Sputum from those with symptoms or CXR suggestive of TB was tested with Xpert MTB/RIF. Risk factors for active TB disease and latent TB infection (LTBI) were identified by logistic regression models. We screened 2857 HHCs for TB between June 2020 and December 2022, with 68 (2.4%) diagnosed with active TB. Of 2621 HHCs eligible for LTBI investigation, 1083 (45.7%) were diagnosed with LTBI. The factors associated with active TB were age, being underweight, diabetes mellitus, urban living, and sleeping in the same house as an index case. Factors associated with LTBI were increasing age and male gender. Conclusions: Screening for HHC including CXR and TST/IGRA yielded a moderate prevalence of TB disease and infection.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38415807

RESUMO

Multiparameter flow cytometry is widely used for acute myeloid leukemia minimal residual disease testing (AML MRD) but is time consuming and demands substantial expertise. Machine learning offers potential advancements in accuracy and efficiency, but has yet to be widely adopted for this application. To explore this, we trained single cell XGBoost classifiers from 98 diagnostic AML cell populations and 30 MRD negative samples. Performance was assessed by cross-validation. Predictions were integrated with UMAP as a heatmap parameter for an augmented/interactive AML MRD analysis framework, which was benchmarked against traditional MRD analysis for 25 test cases. The results showed that XGBoost achieved a median AUC of 0.97, effectively distinguishing diverse AML cell populations from normal cells. When integrated with UMAP, the classifiers highlighted MRD populations against the background of normal events. Our pipeline, MAGIC-DR, incorporated classifier predictions and UMAP into flow cytometry standard (FCS) files. This enabled a human-in-the-loop machine learning guided MRD workflow. Validation against conventional analysis for 25 MRD samples showed 100% concordance in myeloid blast detection, with MAGIC-DR also identifying several immature monocytic populations not readily found by conventional analysis. In conclusion, Integrating a supervised classifier with unsupervised dimension reduction offers a robust method for AML MRD analysis that can be seamlessly integrated into conventional workflows. Our approach can support and augment human analysis by highlighting abnormal populations that can be gated on for quantification and further assessment. This has the potential to speed up MRD analysis, and potentially improve detection sensitivity for certain AML immunophenotypes.

16.
Trop Med Infect Dis ; 9(4)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38668536

RESUMO

Active-case finding (ACF) using chest X-ray is an essential method of finding and diagnosing Tuberculosis (TB) cases that may be missed in Indonesia's routine TB case finding. This study compares active and passive TB case-finding strategies. A retrospective study of TB case notification was conducted. Data between 1 January and 31 December 2021, was used. The population in this study were TB cases notified from Kulon Progo District health facilities, including those found through routine activities or active-case findings. A total of 249 TB cases were diagnosed in Kulon Progo in 2021, and 102 (41%) were bacteriologically confirmed. The TB patients' ages ranged from 0 to 85 years (median 52, IQR 31-61). The majority of cases were male (59%, 147/249) and mostly among people aged 15-59 (61.4%, 153/249). The proportion of clinical TB diagnoses among cases found from active-case findings was 74.7% (68/91) while the proportion among passive-case findings was 50% (79/158). Active-case finding contributed 91 (36.5%) TB cases to the total cases detected in Kulon Progo in 2021. The use of chest X-rays in active-case findings likely contributed to the detection of a higher proportion of clinical TB than in passive-case findings.

17.
Blood ; 118(19): 5126-9, 2011 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-21856867

RESUMO

Ofatumumab, the human CD20 monoclonal antibody that binds a distinct epitope from rituximab, has demonstrated clinical benefit as monotherapy for patients with chronic lymphocytic leukemia refractory to fludarabine and alemtuzumab (FA-ref) and patients refractory to fludarabine with bulky (> 5 cm) lymph nodes (BF-ref). To potentially gain insight into outcomes in patients previously treated with or refractory to rituximab, we performed an ad hoc retrospective analysis in the final 96 FA-ref and 111 BF-ref patients. There were 117 patients previously treated with rituximab (98 rituximab-refractory); 89 patients were rituximab-naive. For rituximab-treated, rituximab-refractory, and rituximab-naive patients, overall response rate was 43%, 44%, and 53%; median progression-free survival was 5.3, 5.5, and 5.6 months; and median overall survival was 15.5, 15.5, and 20.2 months. There were no significant differences in ofatumumab-related infusion reactions, or hematologic or infectious adverse events between subgroups. In summary, ofatumumab monotherapy was effective and well tolerated in patients with fludarabine-refractory chronic lymphocytic leukemia, including in patients with previous rituximab exposure. This trial was registered at www.clinicaltrials.gov as #NCT00349349.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/terapia , Vidarabina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Alemtuzumab , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rituximab , Vidarabina/uso terapêutico
18.
Blood ; 117(24): 6450-8, 2011 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-21498674

RESUMO

We conducted an international phase 2 trial to evaluate 2 dose levels of ofatumumab, a human CD20 mAb, combined with fludarabine and cyclophosphamide (O-FC) as frontline therapy for chronic lymphocytic leukemia (CLL). Patients with active CLL were randomized to ofatumumab 500 mg (n = 31) or 1000 mg (n = 30) day 1, with fludarabine 25 mg/m(2) and cyclophosphamide 250 mg/m(2) days 2-4, course 1; days 1-3, courses 2-6; every 4 weeks for 6 courses. The first ofatumumab dose was 300 mg for both cohorts. The median age was 56 years; 13% of patients had a 17p deletion; 64% had ß2-microglobulin > 3.5 mg/L. Based on the 1996 National Cancer Institute Working Group (NCI-WG) guidelines, the complete response (CR) rate as assessed by an independent review committee was 32% for the 500-mg and 50% for the 1000-mg cohort; the overall response (OR) rate was 77% and 73%, respectively. Based on univariable regression analyses, ß2-microglobulin and the number of O-FC courses were significantly correlated (P < .05) with CR and OR rates and progression-free survival (PFS). The most frequent Common Terminology Criteria (CTC) grade 3-4 investigator-reported adverse events were neutropenia (48%), thrombocytopenia (15%), anemia (13%), and infection (8%). O-FC is active and safe in treatment-naive patients with CLL, including high-risk patients. This trial was registered at www.clinicaltrials.gov as NCT00410163.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Vidarabina/análogos & derivados , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Terapia Combinada , Ciclofosfamida/efeitos adversos , Feminino , Humanos , Imunoterapia/métodos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/efeitos adversos
20.
Eye (Lond) ; 37(13): 2744-2752, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36707639

RESUMO

OBJECTIVES: To evaluate the effect of miosis and laser peripheral iridotomy (LPI) on intraocular lens (IOL) power prediction and ocular biometry in eyes with primary angle closure disease (PACD). METHODS: In this prospective observational study, primary angle closure suspects (PACS), and subjects classified with primary angle closure (PAC)/primary angle-closure glaucoma (PACG) undergoing LPI were enrolled. Ocular biometric parameters were measured with IOLMaster700 at baseline (T0), one week after pilocarpine instillation (T1), and another week post LPI (T2). Biometric changes and the IOL power predicted for emmetropia using Barrett Universal II, Haigis, Holladay2, Hoffer Q and SRK/T formulae were analysed and compared among different time points. RESULTS: 100 eyes of 50 PACS and 50 PAC/PACG patients were enrolled. Following pilocarpine-induced miosis, lens thickness (LT) increased and anterior chamber depth (ACD) decreased (all groups p < 0.01), while white-to-white diameter decreased and central corneal thickness increased significantly only in the PACS cohort (both p < 0.01). Compared to baseline, LPI induced an increase of ACD and a slight decrease of LT in PACS (both p < 0.01), whereas only axial length changed significantly (p = 0.012) in the PAC/PACG cohort. Regardless of the formula used, no significant difference to the predicted IOL power for emmetropia existed among the three time points in each group (all p > 0.1). CONCLUSION: We report the changes of anterior segment parameters induced by miosis and LPI in PACD. These interventions do not significantly affect the IOL power calculation predicted for emmetropia in Chinese eyes when common third-, fourth-and new generation IOL formulae are used.


Assuntos
Glaucoma de Ângulo Fechado , Lasers , Lentes Intraoculares , Humanos , Glaucoma de Ângulo Fechado/cirurgia , Miose/induzido quimicamente , Estudos Prospectivos , Pilocarpina/farmacologia , Mióticos/farmacologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Pressão Intraocular
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