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1.
World J Hepatol ; 16(3): 452-464, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577539

RESUMO

BACKGROUND: A new nomenclature consensus has emerged for liver diseases that were previously known as non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD). They are now defined as metabolic dysfunction-associated steatotic liver disease (MASLD), which includes cardiometabolic criteria in adults. This condition, extensively studied in obese or overweight patients, constitutes around 30% of the population, with a steady increase worldwide. Lean patients account for approximately 10%-15% of the MASLD population. However, the pathogenesis is complex and is not well understood. AIM: To systematically review the literature on the diagnosis, pathogenesis, characteristics, and prognosis in lean MASLD patients and provide an interpretation of these new criteria. METHODS: We conducted a comprehensive database search on PubMed and Google Scholar between January 2012 and September 2023, specifically focusing on lean NAFLD, MAFLD, or MASLD patients. We include original articles with patients aged 18 years or older, with a lean body mass index categorized according to the World Health Organization criteria, using a cutoff of 25 kg/m2 for the general population and 23 kg/m2 for the Asian population. RESULTS: We include 85 studies in our analysis. Our findings revealed that, for lean NAFLD patients, the prevalence rate varied widely, ranging from 3.8% to 34.1%. The precise pathogenesis mechanism remained elusive, with associations found in genetic variants, epigenetic modifications, and adaptative metabolic response. Common risk factors included metabolic syndrome, hypertension, and type 2 diabetes mellitus, but their prevalence varied based on the comparison group involving lean patients. Regarding non-invasive tools, Fibrosis-4 index outperformed the NAFLD fibrosis score in lean patients. Lifestyle modifications aided in reducing hepatic steatosis and improving cardiometabolic profiles, with some medications showing efficacy to a lesser extent. However, lean NAFLD patients exhibited a worse prognosis compared to the obese or overweight counterpart. CONCLUSION: MASLD is a complex disease comprising epigenetic, genetic, and metabolic factors in its pathogenesis. Results vary across populations, gender, and age. Limited data exists on clinical practice guidelines for lean patients. Future studies employing this new nomenclature can contribute to standardizing and generalizing results among lean patients with steatotic liver disease.

2.
Front Public Health ; 11: 1191722, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790721

RESUMO

Background: Sexually transmitted infections (STIs) are a serious public health problem worldwide, especially among reproductive-age women. The early sexual onset of sexual intercourse (EOSI) has been suggested as a risk factor, although there is no data at the national level. Objective: To evaluate the association between EOSI and STIs in Peruvian women of childbearing age. Methods: Analytical cross-sectional study with secondary data analyzes of the Peruvian Demographic and Family Health Survey 2018. The outcome was the presence of STIs in the last 12 months and the exposure variable was EOSI (age < 15 years at the time of their first sexual experience). To evaluate the association of interest, crude and adjusted prevalence ratios (aPRs) were calculated using generalized linear models with Poisson family and logarithmic link function. Results: We analyzed data from 31,028 women of childbearing age. The 11.3% reported having STIs in the last 12 months and 20.2% of the participants had an EOSI. After adjusting for potential confounders, we found that EOSI was associated with STIs (aPR: 1.27; 95% CI: 1.08-1.50; p = 0.005). When conducting stratified analysis by area of residence and number of sexual partners, this association was maintained in women living in urban areas (aPR: 1.36; 95% CI: 1.11-1.66; p = 0.003) those who did not report having a history of multiple sexual partners (aPR: 1.27; 95% CI: 1.08-1.51; p = 0.005), and those in the middle (aPR: 1.42; 95% CI: 1.03-1.97; p = 0.034) and highest (aPR: 2.12; 95% CI: 1.33-3.39; p = 0.002) wealth quintiles. Conclusion: Among reproductive-age women from Peru, EOSI was associated with STIs, especially in women living in urban areas, with no history of multiple sexual partners, and belonging to the middle to higher wealth index. The implementation of measures to prevent EOSI and fostering appropriate sexual health counseling for women with EOSI is advised.


Assuntos
Comportamento Sexual , Infecções Sexualmente Transmissíveis , Humanos , Feminino , Adolescente , Peru/epidemiologia , Estudos Transversais , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Parceiros Sexuais
3.
J Allied Health ; 52(3): 234-238, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37728355

RESUMO

AIMS: Previous research during novel disease outbreaks shows mental health amongst frontline healthcare workers to be of concern. Currently, there are limited data regarding mental health of rehabilitation professionals working through the COVID-19 pandemic in the acute care setting. This research examines the impact on mental health amongst rehabilitation professionals working in the acute care setting during the COVID-19 pandemic to better understand what administrative policies can be implemented to support workers. METHODS: The study administered a 22-question online survey to 221 occupational therapists, physical therapists, and speech-language pathologists working in acute care/hospital settings. Data collection occurred over 30 days in late 2021. Data were analyzed using chi-squared analysis and t-test of means to identify significant differences between demographic variables and reported emotional health outcomes. RESULTS: Those of higher age reported higher frequencies of depression and anxiety symptoms and fatigue (p >0.05). Professionals with higher COVID-19 contact hours had higher emotional distress and suicidal thoughts (p >0.05). Compared to certified occupational therapy assistants and physical therapy assistants, evaluating therapists had significantly higher reports of lifestyle impacts (p >0.05). CONCLUSION: These finding serve as considerations for management decisions for rehabilitation professionals during future disease outbreaks. Targeted support must be shown to employees of older age and evaluating therapists. This shows that administrators must consider implementing more equal spread of patient contact to avoid serious impacts.


Assuntos
COVID-19 , Terapia Ocupacional , Fisioterapeutas , Humanos , Saúde Mental , Pandemias , COVID-19/epidemiologia
4.
Clin Exp Gastroenterol ; 16: 129-136, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601009

RESUMO

Background: Cardiovascular diseases are responsible for the majority of deaths resulting from non-alcoholic fatty liver disease (NAFLD). NAFLD is associated with hypertension and this is a key predictor of severe liver outcomes and an indicator of nonspecific portal fibrosis. Aim: To assess the association between hypertension and NAFLD severity. Methods: We conducted a secondary analysis of data from Peruvian adults with obesity and NAFLD who attended a Peruvian bariatric center. The severity of NAFLD was assessed using the Fatty Liver Inhibition of Progression algorithm / Steatosis, Activity and Fibrosis score. Hypertension was determined by either being recorded in the medical records or if the patient had a systolic pressure ≥ 140 mmHg or diastolic pressure ≥ 90 mmHg. To evaluate the association of interest, we calculated crude and adjusted prevalence ratios (aPR) using Poisson generalized linear models with logarithmic link function and robust variances. For the multivariable models, we adjusted for age, sex, physical activity and smoking. Results: Our study included 234 participants. The prevalence of hypertension was 19.2%, while the prevalence of severe NAFLD was 46.2%. After adjusting for confounders, the prevalence of hypertension was found to be significantly higher in the severe NAFLD group compared to the non-severe group (aPR = 1.33; 95% CI: 1.03-1.74). When stratified by the presence of metabolic syndrome (MetS), the association remained significant only in the group without MetS (aPR = 1.80; 95% CI: 1.05-3.11). Conclusion: We found an association between hypertension and severe NAFLD in adults with obesity, particularly in those without MetS.

5.
Behav Brain Res ; 451: 114526, 2023 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-37271313

RESUMO

This study aimed to evaluate the behavioral and energy metabolism parameters in female mice subjected to obesity and offspring deprivation (OD) stress. Eighty female Swiss mice, 40 days old, were weighed and divided into two groups: Control group (control diet, n = 40) and Obese group (high-fat diet, n = 40), for induction of the animal model of obesity, the protocol was based on the consumption of a high-fat diet and lasted 8 weeks. Subsequently, the females were subjected to pregnancy, after the birth of the offspring, were divided again into the following groups (n = 20): Control non-deprived (ND), Control + OD, Obese ND, and Obese + OD, for induction of the stress protocol by OD. After the offspring were 21 days old, weaning was performed and the dams were subjected to behavioral tests. The animals were humanely sacrificed, the brain was removed, and brain structures were isolated to assess energy metabolism. Both obesity and OD led to anhedonia in the dams. It was shown that the structures most affected by obesity and OD are the hypothalamus and hippocampus, as evidenced by the mitochondrial dysfunction found in these structures. When analyzing the groups separately, it was observed that OD led to more pronounced mitochondrial damage; however, the association of obesity with OD, as well as obesity alone, also generated damage. Thus, it is concluded that obesity and OD lead to anhedonia in animals and to mitochondrial dysfunction in the hypothalamus and hippocampus, which may lead to losses in feeding control and cognition of the dams.


Assuntos
Anedonia , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Camundongos , Feminino , Animais , Humanos , Obesidade/metabolismo , Dieta Hiperlipídica/efeitos adversos , Desmame , Metabolismo Energético
6.
J Clin Med ; 11(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35683387

RESUMO

Objective: We systematically assessed the efficacy of liraglutide in non-diabetic obese adults. Methods: Six databases were searched up to July 2021 for randomized controlled trials (RCTs) assessing liraglutide versus placebo in obese adults. Primary outcomes were body weight and body mass index (BMI). Secondary outcomes were treatment-emergent adverse events (TEAEs), hypoglycemic episodes, HbA1c, and blood pressure. Effect measures were risk ratio (RR) or mean difference (MD) with their confidence interval (95%CI). Random-effects models and inverse variance meta-analyses were used. Quality of evidence was assessed using GRADE. Results: Twelve RCTs (n = 8249) were included. In comparison to placebo, liraglutide reduced body weight (MD −3.35 kg; 95%CI −4.65 to −2.05; p < 0.0001), and BMI (MD −1.45 kg/m2; 95%CI −1.98 to −0.91; p < 0.0001). Liraglutide did not reduce TEAEs (RR 1.08; 95%CI 0.92 to 1.27; p = 0.25), and Hb1Ac (MD −0.76%; 95%CI −2.24 to 0.72; p = 0.31). Furthermore, it did not increase hypoglycemic episodes (RR 2.01; 95%CI 0.37 to 11.02; p = 0.28). Finally, liraglutide reduced systolic blood pressure (MD −3.07 mmHg; 95%CI −3.66 to −2.48; p < 0.0001) and diastolic blood pressure (MD −1.01 mmHg; 95%CI −1.55 to −0.47; p = 0.0003). Seven RCTs had a high risk of bias. Subgroup analyses by length of treatment and doses had effects similar to the overall analyses. Quality of evidence was low or very low for most outcomes. Conclusions: In non-diabetic obese adults, liraglutide reduced body weight, BMI and blood pressure in comparison to placebo. Adverse events, Hb1Ac levels and hypoglycemic episodes were not different than placebo.

7.
Einstein (Sao Paulo) ; 19: eAO6289, 2021.
Artigo em Inglês, Português | MEDLINE | ID: mdl-34932757

RESUMO

OBJECTIVE: To investigate the level of awareness of primary immunodeficiency diseases among physicians working at Instituto Nacional de Salud del Niño. METHODS: Cross-sectional study including pediatric residents and pediatricians working at the Instituto Nacional de Salud del Niño during the study period (2017-2019). Physicians working at the immunology unit and surgery departments were excluded. Three aspects of awareness of primary immunodeficiency diseases were investigated: education, general knowledge, and diagnostic suspicion and actions taken in the face of suspicion. RESULTS: This sample comprised 83 physicians with a median age of 33 years. Most physicians were women (71.1%) and half were pediatric residents. During their undergraduate studies, 43.1% had taken primary immunodeficiency disease courses, and 39.2% had attended conferences on this topic. During their residency training, 25.9% had taken primary immunodeficiency disease courses, and 60.3% had participated in conferences on this topic. Among pediatricians, 50% had taken primary immunodeficiency disease courses, and 53.1% had attended conferences on this topic. Only 39.8% of physicians reported being familiar with the list of 10 warning signs developed by the Jeffrey Modell Foundation. More than half of physicians considered the lack of access to laboratory tests the major challenge in making diagnosis of primary immunodeficiency diseases. CONCLUSION: This study revealed limited awareness of primary immunodeficiency diseases among physicians working at Instituto Nacional de Salud del Niño. Although most physicians suspected primary immunodeficiency diseases in patients with a history of recurrent infections and frequent use of antibiotics, not all of them were familiar with the list of 10 warning signs proposed by the Jeffrey Modell Foundation, nor were they able to describe ancillary tests requested in suspected cases.


Assuntos
Antibacterianos , Doenças da Imunodeficiência Primária , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Peru/epidemiologia
8.
Rev. cuba. hematol. inmunol. hemoter ; 37(2): e1235, 2021. graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1289431

RESUMO

Introducción: La púrpura trombocitopénica trombótica puede presentarse en menos del 2 por ciento de los pacientes con lupus eritematoso sistémico. Esta asociación implica un aumento de la mortalidad y un periodo de remisión más prolongado. Objetivo: Se presenta el caso de paciente peruana que desarrolló esta asociación y presentó complicaciones relacionadas con shock séptico. Caso clínico: Paciente femenina, con antecedente de púrpura trombocitopénica inmunológica y lupus eritematoso sistémico, acudió a emergencia por presentar palidez cutánea generalizada, petequias en miembros inferiores y hematuria. Posteriormente, su estado de salud se complicó con un shock séptico y deterioro del nivel de conciencia. Por todo esto, es referida a un hospital de mayor complejidad y hace su ingreso a la unidad de cuidados intensivos. La clínica y los exámenes de laboratorio revelaron hallazgos compatibles con púrpura trombocitopénica trombótica (anemia grave, plaquetopenia, esquistositosis) y lupus eritematoso sistémico activo grave. Antes de ser referida, recibió pulsos de metilprednisona y prednisona. Ya en unidad de cuidados intensivos, se cambió a soporte ventilatorio y tratamiento antibiótico. Con el diagnóstico presuntivo de púrpura trombocitopénica trombótica, asociada a lupus eritematoso sistémico activo grave, se inició tratamiento oportuno con plasmaféresis, corticoterapia y ciclofosfamida. La paciente recuperó los niveles plaquetarios y el nivel óptimo de conciencia. Actualmente acude a controles. Conclusiones: La púrpura trombocitopénica trombótica es una emergencia hematológica con alta mortalidad en ausencia de tratamiento. Su reconocimiento oportuno, sin dosificación de la proteína ADAMTS13, en esta asociación poco frecuente con lupus eritematoso sistémico es importante en el buen pronóstico del paciente(AU)


Introduction: Thrombotic thrombocytopenic purpura may occur in less than 2 percent of patients with systemic lupus erythematosus. This association implies an increase in mortality and a longer remission period. Objective: We present the case of a Peruvian woman who developed this association, and complicating herself with septic shock. Clinical case: A female patient, with a history of immunological thrombocytopenic purpura and systemic lupus erythematosus, comes to the emergency room due to generalized skin pallor, lower limb petechiae and hematuria. Subsequently, her state of health gets complicated with a septic shock and deterioration of the level of consciousness. For all of this, she was referred to a hospital of greater complexity and makes admission to an intensive care unit. Clinical and laboratory tests revealed findings compatible with thrombotic thrombocytopenic purpura (severe anemia, platelet disease, schistositosis) and severe active systemic lupus erythematosus. Before being referred, she received pulses of methylprednisone and prednisone. When already in the intensive care unit, it was changed to ventilatory support andantibiotic treatment. With the presumptive diagnosis of thrombotic thrombocytopenic purpura, associated with severe active systemic lupus erythematosus, a timely treatment was initiated with plasmapheresis, corticosteroids and cyclophosphamide. The patient recovered platelet levels and optimal level of consciousness. She is currently going to controls. Conclusions: Thrombotic thrombocytopenic purpura is a hematological emergency with high mortality in the absence of treatment. Its timely recognition, without dosing of ADAMTS13 protein, in this rare association with systemic lupus erythematosus is important in the good prognosis of the patient(AU)


Assuntos
Humanos , Feminino , Púrpura Trombocitopênica/complicações , Plasmaferese/métodos , Unidades de Terapia Intensiva , Lúpus Eritematoso Sistêmico/complicações , Púrpura Trombocitopênica/tratamento farmacológico
9.
J Gastrointestin Liver Dis ; 30(1): 110-121, 2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33723542

RESUMO

BACKGROUND AND AIMS: Vasoactive agents with endoscopic therapy are used to treat acute variceal bleeding (AVB). There are two main groups of vasoactive agents: terlipressin and vasopressin (T-V), and octreotide and somatostatin (O-S). However, the benefit/harm balance is unclear. Our aim was to assess the efficacy and safety of T-V versus O-S for the management of AVB. METHODS: We performed a systematic search for randomized controlled trials (RCTs) in PubMed, Scopus, and CENTRAL. Our main outcomes were mortality and adverse events. Secondary outcomes were bleeding control, rebleeding, blood transfusion, hospital stay. We evaluated the certainty of evidence using GRADE methodology. RESULTS: We included 21 RCTs. The risk of mortality (RR: 1.01; 95%CI: 0.83-1.22), bleeding control (RR: 0.96; 95%CI: 0.91-1.02; I 2 =53%), early rebleeding (RR: 0.91; 95%CI: 0.66-1.24: I 2 =0%), late rebleeding (RR: 0.94; 95 CI: 0.56-1.60; I 2 =0%), blood transfusion (MD: 0.04; 95%CI: -0.31-0.39; I 2 =68%) and hospital stay (MD: -1.06; 95%CI: -2.80-0.69; I 2 =0%) were similar between T-V and O-S groups. Only 15 studies reported adverse events, which were significantly higher in the T-V compared to the O-S group (RR 2.39; 95%CI: 1.58-3.63; I 2 =57%). The certainty of evidence was moderate for the main outcomes, and low or very low for others. CONCLUSIONS: In cirrhotic patients with AVB, those treated with T-V had similar mortality risk compared to O-S. However, the use of T-V showed an increased risk of adverse events compared to O-S.


Assuntos
Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/tratamento farmacológico , Hemorragia Gastrointestinal/etiologia , Terlipressina/uso terapêutico , Vasopressinas/uso terapêutico , Adulto , Idoso , Transfusão de Sangue , Feminino , Hemorragia Gastrointestinal/mortalidade , Humanos , Tempo de Internação , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Octreotida/uso terapêutico , Recidiva , Somatostatina/uso terapêutico , Terlipressina/efeitos adversos , Resultado do Tratamento , Vasopressinas/efeitos adversos
10.
Artigo em Espanhol, Inglês | LILACS-Express | LILACS | ID: biblio-1177964

RESUMO

El cálculo de tamaño de muestra es un aspecto esencial del diseño de estudios cuantitativos. Un adecuado tamaño de muestra nos permite determinar cuál es la mínima cantidad de participantes necesarios para probar nuestra hipótesis de interés. De esta manera, podemos reducir costos, maximizar el uso de nuestros recursos de investigación y garantizar la factibilidad del estudio. Contradictoriamente, a pesar de su relevancia muy pocos investigadores dominan esta habilidad. Esta revisión tiene por objeto revisar los conceptos básicos para realizar un cálculo de tamaño de muestra y compartir códigos de Stata y R específicamente diseñados para facilitar estos cálculos.


The calculation of sample size is an essential aspect of the design of quantitative studies. An adequate sample size allows us to determine the minimum number of participants necessary to test our hypothesis of interest. Hence, we can reduce costs, maximize the use of our research resources and guarantee the feasibility of the study. Contradictorily, despite its relevance, very few researchers dominate this skill. This review aims to review the basics of sample size calculation and share Stata and R codes specifically designed to facilitate these calculations.

11.
Anal Chem ; 71(19): 4232-6, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10517145

RESUMO

Concerns about the use of anthrax spores as a weapon of mass destruction have motivated the development of portable instruments capable of detecting and monitoring a suspected release of the agent. Optimal detection of bacterial spores by PCR requires that the spores be disrupted to make the endogenous DNA available for amplification. The entire process of spore lysis, PCR, and detection can take several hours using conventional methods and instruments. In this report, a minisonicator and prototype spore lysis cartridge were built to disrupt Bacillus spores in 30 s for rapid, real-time PCR analysis. Utilization of the minisonicator improved PCR analysis by decreasing the limit of detection, reducing the time of detection, and increasing the signal amplitude. Total time of spore disruption and detection using the minisonicator and a microchip PCR instrument was less than 15 min.


Assuntos
DNA Bacteriano/análise , Reação em Cadeia da Polimerase/métodos , Sonicação/instrumentação , Esporos Bacterianos/genética , Bacillus anthracis/genética , Citometria de Fluxo , Fatores de Tempo
12.
Cytometry ; 37(2): 160-3, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10486529

RESUMO

BACKGROUND: We previously reported a new optical configuration, in which both the side scatter and the fluorescence are collected using the index-guided, total internal reflection of a flow stream in air (the flow-stream waveguide). METHODS: Using a mixture of 0.202-microm and 0.093-microm diameter polystyrene beads, we have characterized the side scatter (SSC) sensitivity of a custom-built flow cytometer (miniFlo) which incorporates a flow-stream waveguide. RESULTS: The SSC-triggered SSC signal of 0.093-microm polystyrene beads in water was almost baseline resolved from the background. We also measured the SSC-triggered SSC signal of the same beads in water on our FACScan, which is a commercial unit with the conventional optical arrangement that uses a custom imaging objective to collect light from a sheath flow cuvette in perpendicular direction-the signal from 0.093-microm beads was not resolved from the background. CONCLUSIONS: The SSC sensitivity of miniFlo is one of the best reported in the literature. Cytometry 37:160-163, 1999. Published 1999 Wiley-Liss, Inc.


Assuntos
Citometria de Fluxo/métodos , Citometria de Fluxo/instrumentação , Sensibilidade e Especificidade
14.
Clin Chem ; 44(10): 2191-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9761255

RESUMO

An array of PCR microchips for rapid, parallel testing of samples for pathogenic microbes is described. The instrument, called the Advanced Nucleic Acid Analyzer (ANAA), utilizes 10 silicon reaction chambers with thin-film resistive heaters and solid-state optics. Features of the system include efficient heating and real-time monitoring, low power requirements for battery operation, and no moving parts for reliability and ruggedness. We analyzed cultures of Erwinia herbicola vegetative cells, Bacillus subtilis spores, and MS2 virions, which simulated pathogenic microbes such as Yersinia pestis, Bacillus anthracis spores, and Venezuelan equine encephalitis, respectively. Detection of microbes was achieved in as little as 16 min with detection limits of 10(5)-10(7) organisms/L (10(2)-10(4) organisms/mL).


Assuntos
DNA Bacteriano/análise , DNA Viral/análise , Reação em Cadeia da Polimerase/instrumentação , Bacillus subtilis/genética , Bacillus subtilis/patogenicidade , Erwinia/genética , Erwinia/patogenicidade , Fluorometria , Levivirus/genética , Levivirus/patogenicidade , Miniaturização , Sensibilidade e Especificidade
15.
Cytometry ; 24(1): 27-31, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8723899

RESUMO

We report a new physical configuration for the detection of perpendicular light scatter or fluorescence in flow cytometry when using a fluid stream in air. This configuration increases the signal-to-noise ratio and narrows the coefficient of variation for uniformly sized latex spheres when compared to using a microscope objective to collect such light. The new technique views the scattered light that is trapped within the optical waveguide that is naturally formed by the flow stream in air. One efficient and simple way to detect the light trapped within this optical waveguide is to place one end of a fiber optic, with a conically polished tip and sufficiently large-core diameter, directly into the flow stream and to place an optical detector at the fiber's other end. For perpendicular light scatter, the flow-stream waveguide achieves high collection efficiency (NA = 0.88) as well as high efficiency of optical through put due to lack of surfaces between the light scatterers and the detector. We obtained 10-fold higher signals with this technique than with a long-working-distance microscope objective. The flow-stream waveguide is also much easier to align than traditional microscope-lens-based systems.


Assuntos
Citometria de Fluxo/métodos , Luz , Tecnologia de Fibra Óptica , Fibras Ópticas , Espalhamento de Radiação
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