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1.
Sensors (Basel) ; 20(11)2020 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-32545279

RESUMEN

This paper describes the possibility of using an Electrically Programmable Analog Device (EPAD) as a gamma radiation sensor. Zero-biased EPAD has the lowest fading and the highest sensitivity in the 300 Gy dose range. Dynamic bias of the control gate during irradiation was presented for the first time; this method achieved higher sensitivity compared to static-biased EPADs and better linear dependence. Due to the degradation of the transfer characteristics of EPAD during irradiation, a function of the safe operation area has been found that determines the maximum voltage at the control gate for the desired dose, which will not lead to degradation of the transistor. Using an energy band diagram, it was explained why the zero-biased EPAD has higher sensitivity than the static-biased EPAD.

2.
Pediatr Rheumatol Online J ; 16(1): 73, 2018 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-30458827

RESUMEN

OBJECTIVE: To quantify the impact of inflammatory brain diseases in the pediatric population on health-related quality of life, including the subdomains of physical, emotional, school and social functioning. METHODS: This was a multicenter, observational cohort study of children (< 18 years of age) diagnosed with inflammatory brain disease (IBrainD). Patients were included if they had completed at least one Health Related Quality of Life Questionnaire (HRQoL). HRQoL was measured using the Pediatric Quality of Life Inventory Version 4.0 (PedsQL) Generic Core Scales, which provided a total score out of 100. Analyses of trends were performed using linear regression models adjusted for repeated measures over time. RESULTS: In this study, 145 patients were included of which 80 (55%) were females. Cognitive dysfunction was the most common presenting symptoms (63%), and small vessel childhood primary angiitis of the CNS was the most common diagnosis (33%). The mean child's self-reported PedsQL total score at diagnosis was 68.4, and the mean parent's proxy-reported PedsQL score was 63.4 at diagnosis. Child's self-reported PedsQL scores reflected poor HRQoL in 52.9% of patients at diagnosis. Seizures or cognitive dysfunction at presentation was associated with statistically significant deficits in HRQoL. CONCLUSION: Pediatric IBrainD is associated with significantly diminished health-related quality of life. Future research should elucidate why these deficits occur and interventions should focus on improving HRQoL in the most affected subdomains, in particular for children presenting with seizures and cognitive dysfunction.


Asunto(s)
Encefalopatías/diagnóstico , Calidad de Vida , Adolescente , Encefalopatías/psicología , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Masculino , Padres/psicología , Psicometría/métodos , Factores de Riesgo , Encuestas y Cuestionarios
3.
Arthritis Rheumatol ; 69(7): 1470-1479, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28371513

RESUMEN

OBJECTIVE: To characterize the early disease course in childhood-onset antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and the 12-month outcomes in children with AAV. METHODS: Eligible subjects were children entered into the Pediatric Vasculitis Initiative study who were diagnosed before their eighteenth birthday as having granulomatosis with polyangiitis (Wegener's), microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis (Churg-Strauss), or ANCA-positive pauci-immune glomerulonephritis. The primary outcome measure was achievement of disease remission (Pediatric Vasculitis Activity Score [PVAS] of 0) at 12 months with a corticosteroid dosage of <0.2 mg/kg/day. Secondary outcome measures included the rates of inactive disease (PVAS of 0, with any corticosteroid dosage) and rates of improvement at postinduction (4-6 months after diagnosis) and at 12 months, presence of damage at 12 months (measured by a modified Pediatric Vasculitis Damage Index [PVDI]; score 0 = no damage, score 1 = one damage item present), and relapse rates at 12 months. RESULTS: In total, 105 children with AAV were included in the study. The median age at diagnosis was 13.8 years (interquartile range 10.9-15.8 years). Among the study cohort, 42% of patients achieved remission at 12 months, 49% had inactive disease at postinduction (4-6 months), and 61% had inactive disease at 12 months. The majority of patients improved, even if they did not achieve inactive disease. An improvement in the PVAS score of at least 50% from time of diagnosis to postinduction was seen in 92% of patients. Minor relapses occurred in 12 (24%) of 51 patients after inactive disease had been achieved postinduction. The median PVDI damage score at 12 months was 1 (range 0-6), and 63% of patients had ≥1 PVDI damage item scored as present at 12 months. CONCLUSION: This is the largest study to date to assess disease outcomes in pediatric AAV. Although the study showed that a significant proportion of patients did not achieve remission, the majority of patients responded to treatment. Unfortunately, more than one-half of this patient cohort experienced damage to various organ systems early in their disease course.


Asunto(s)
Corticoesteroides/uso terapéutico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Enfermedades Renales/tratamiento farmacológico , Enfermedades Pulmonares/tratamiento farmacológico , Sistema de Registros , Adolescente , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Azatioprina/uso terapéutico , Niño , Estudios de Cohortes , Ciclofosfamida/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Enfermedades Renales/etiología , Enfermedades Pulmonares/etiología , Masculino , Metotrexato/uso terapéutico , Ácido Micofenólico/uso terapéutico , Estudios Prospectivos , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Rituximab/uso terapéutico
4.
Arthritis Rheumatol ; 68(10): 2514-26, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27111558

RESUMEN

OBJECTIVE: To uniquely classify children with microscopic polyangiitis (MPA), to describe their demographic characteristics, presenting clinical features, and initial treatments in comparison to patients with granulomatosis with polyangiitis (Wegener's) (GPA). METHODS: The European Medicines Agency (EMA) classification algorithm was applied by computation to categorical data from patients recruited to the ARChiVe (A Registry for Childhood Vasculitis: e-entry) cohort, with the data censored to November 2015. The EMA algorithm was used to uniquely distinguish children with MPA from children with GPA, whose diagnoses had been classified according to both adult- and pediatric-specific criteria. Descriptive statistics were used for comparisons. RESULTS: In total, 231 of 440 patients (64% female) fulfilled the classification criteria for either MPA (n = 48) or GPA (n = 183). The median time to diagnosis was 1.6 months in the MPA group and 2.1 months in the GPA group (ranging to 39 and 73 months, respectively). Patients with MPA were significantly younger than those with GPA (median age 11 years versus 14 years). Constitutional features were equally common between the groups. In patients with MPA compared to those with GPA, pulmonary manifestations were less frequent (44% versus 74%) and less severe (primarily, hemorrhage, requirement for supplemental oxygen, and pulmonary failure). Renal pathologic features were frequently found in both groups (75% of patients with MPA versus 83% of patients with GPA) but tended toward greater severity in those with MPA (primarily, nephrotic-range proteinuria, requirement for dialysis, and end-stage renal disease). Airway/eye involvement was absent among patients with MPA, because these GPA-defining features preclude a diagnosis of MPA within the EMA algorithm. Similar proportions of patients with MPA and those with GPA received combination therapy with corticosteroids plus cyclophosphamide (69% and 78%, respectively) or both drugs in combination with plasmapheresis (19% and 22%, respectively). Other treatments administered, ranging in decreasing frequency from 13% to 3%, were rituximab, methotrexate, azathioprine, and mycophenolate mofetil. CONCLUSION: Younger age at disease onset and, perhaps, both gastrointestinal manifestations and more severe kidney disease seem to characterize the clinical profile in children with MPA compared to those with GPA. Delay in diagnosis suggests that recognition of these systemic vasculitides is suboptimal. Compared with adults, initial treatment regimens in children were comparable, but the complete reversal of female-to-male disease prevalence ratios is a provocative finding.


Asunto(s)
Granulomatosis con Poliangitis/fisiopatología , Hemorragia/fisiopatología , Fallo Renal Crónico/fisiopatología , Enfermedades Pulmonares/fisiopatología , Poliangitis Microscópica/fisiopatología , Síndrome Nefrótico/fisiopatología , Insuficiencia Respiratoria/fisiopatología , Adolescente , Corticoesteroides/uso terapéutico , Distribución por Edad , Anticuerpos Anticitoplasma de Neutrófilos , Asia/epidemiología , Azatioprina/uso terapéutico , Canadá/epidemiología , Niño , Preescolar , Estudios de Cohortes , Ciclofosfamida/uso terapéutico , Quimioterapia Combinada , Europa (Continente)/epidemiología , Femenino , Granulomatosis con Poliangitis/complicaciones , Granulomatosis con Poliangitis/epidemiología , Granulomatosis con Poliangitis/terapia , Hemorragia/etiología , Humanos , Inmunosupresores/uso terapéutico , Lactante , Fallo Renal Crónico/etiología , Fallo Renal Crónico/terapia , Enfermedades Pulmonares/etiología , Masculino , Metotrexato/uso terapéutico , Poliangitis Microscópica/complicaciones , Poliangitis Microscópica/epidemiología , Poliangitis Microscópica/terapia , Ácido Micofenólico/uso terapéutico , Síndrome Nefrótico/etiología , Terapia por Inhalación de Oxígeno , Plasmaféresis , Proteinuria/etiología , Diálisis Renal , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Rituximab/uso terapéutico , Estados Unidos/epidemiología
5.
Vojnosanit Pregl ; 73(4): 326-36, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29308862

RESUMEN

Background/Aim: Analysis of air quality in Serbia indicates that the city of Nis belongs to a group of cities characterized by the third category of air quality (excessive air pollution). The aim of the study was to analyze the degree of causality between ambient air quality affected by particulate matter of 10 µm (PM10) and carbon monoxide (CO) and the incidence of respiratory diseases in preschool children in the city of Nis. Methods: We quantified the influence of higher PM10 concentrations and carbon monoxide comprising motor vehicle exhausts in the city of Nis on the occurrence of unwanted health effects in preschool children by means of the hazard quotient (HQ), individual health risk (Ri), and the probability of cancer (ICR). The methodology used was according to the US Environmental Protection Agency (EPA), and it included basic scientific statistical methods, compilation methods, and the relevant mathematical methods for assessing air pollution health risk, based on the use of attribute equations. Results: Measurement of ambient air pollutant concentrations in the analyzed territory for the entire monitoring duration revealed that PM10 concentrations were significantly above the allowed limits during 80% of the days. The maximum measured PM10 concentration was 191.6 µg/m3, and carbon monoxide 5.415 mg/m3. The incidence of respiratory diseases in the experimental group, with a prominent impact of polluted air was 57.17%, whereas the incidence in the control group was considerably lower, 41.10 %. There were also significant differences in the distribution of certain respiratory diseases. Conclusion: In order to perform good causal analysis of air quality and health risk, it is very important to establish and develop a system for long-term monitoring, control, assessment, and prediction of air pollution. We identified the suspended PM10 and CO as ambient air pollutants causing negative health effects in the exposed preschool children population


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Monóxido de Carbono/efectos adversos , Material Particulado/efectos adversos , Trastornos Respiratorios/epidemiología , Población Urbana , Preescolar , Humanos , Incidencia , Serbia/epidemiología
6.
Adv Clin Exp Med ; 24(3): 429-36, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26467130

RESUMEN

BACKGROUND: Microwaves from mobile phones are one of the environmental toxicants that are capable of compromising male fertility by inducing oxidative stress and apoptosis in the testes. Melatonin is a lipophilic tryptophan indole amine and a potent antioxidant. OBJECTIVES: The aim of the study was to evaluate the effect of melatonin treatment on oxidative stress parameters and DNA fragmentation in the testicular tissue of rats exposed to microwave radiation (4 h/day). MATERIAL AND METHODS: Adult Wistar rats were divided in 4 groups: I--treated with saline; II--treated with melatonin; III--exposed to microwaves; IV--exposed to microwaves and treated with melatonin. The melatonin (2 mg/kg ip) was administered daily. The animals were sacrificed after 20, 40 and 60 days. RESULTS: Melatonin treatment prevented previously registered increases in malondialdehyde after only 20 days. Furthermore, it reversed the effects of microwave exposure on xanthine oxidase (after 40 days) and acid-DNase activity (after 20 days). However, neither protein carbonyl content nor catalase and alkaline Dnase activity were changed due to melatonin treatment. CONCLUSIONS: Melatonin exerts potent antioxidant effects in the testes of rats exposed to microwaves by decreasing the intensity of oxidative stress; it also reduces DNA fragmentation.


Asunto(s)
Antioxidantes/farmacología , Daño del ADN/efectos de los fármacos , Melatonina/farmacología , Microondas/efectos adversos , Estrés Oxidativo/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Biomarcadores/metabolismo , Citoprotección , Desoxirribonucleasas/metabolismo , Masculino , Malondialdehído/metabolismo , Ratas Wistar , Testículo/metabolismo , Testículo/patología , Factores de Tiempo , Xantina Oxidasa/metabolismo
7.
Appl Radiat Isot ; 102: 29-34, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25933407

RESUMEN

The behavior of radiation-induced fixed traps (FTs) in gate oxide and radiation-induced switching traps (STs) near and at the gate oxide/substrate interface during irradiation up to high absorbed doses has been considered. The zero-bias voltage regime, the simplest and most popular solution in practice, was chosen. Indeed, it is very difficult to predict the creation of radiation defects in the case of low electric fields, because there is a compromise between the external low electric fields induced by work function differences and the internal electrical fields induced by radiation-induced charged defects in the oxide. It was shown that the density of FTs is higher than the density of STs for lower absorbed doses, though the trend is reversed for doses greater than 700Gy. Although the number of FTs is much higher than the number of STs, many FTs are located in the bulk, far from the oxide/semiconductor interface and their influence on channel carriers is much smaller than the influence of STs that are located closer to the channel. The equation for fitting the threshold voltage components induced by FTs (ΔVft) and by STs (ΔVst) is proposed and very good fittings are obtained. It is shown that five experimental irradiation points are sufficient to draw a good conclusion about the values of the fitting parameters, i.e., the voltage saturation values and the degree of linearity.

9.
J Clin Immunol ; 34(3): 304-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24481607

RESUMEN

Severe combined immunodeficiency (SCID), including the 'variant' Omenn syndrome (OS), represent a heterogeneous group of monogenic disorders characterized by defect in differentiation of T- and/or B lymphocytes and susceptibility to infections since birth. In the period of 25 years, between January 1986 and December 2010, a total of 21 patients (15 SCID, 6 OS) were diagnosed in Mother & Child Health Institute of Serbia, a tertiary-care teaching University hospital and a national referral center for patients affected with primary immunodeficiency (PID). The diagnoses were based on anamnestic data, clinical findings, and immunological and genetic analysis. The median age at the onset of the first infection was the 2nd month of life. Seven (33 %) patients had positive family history for SCID. Out of five male infants with T-B+NK- SCID phenotype, mutation analysis revealed interleukin-2 (common) gamma-chain receptor (IL2RG) mutations in 3 with positive X-linked family history, and Janus-kinase (JAK)-3 gene defects in the other two. Six patients had T-B-NK+ SCID phenotype and further 6 features of OS, 11 of which had recombinase-activating gene (RAG1or RAG2) and 1 Artemis gene mutations. One child with T+B+NK+ SCID phenotype as well had proven RAG mutation. One child each with T-B+NK+ SCID phenotype, CD8 lymphopenia and unknown phenotype remained without known underlying genetic defect. Of the eight patients who underwent hematopoetic stem cell transplant (HSCT) 5 survived, the other 13 died between 2 days and 12 months after diagnosis was made. Early diagnosis of SCID, before onset of severe infections, offers possibility for HSCT and cure. Education of primary-care pediatricians, in particular including awareness of the risk of using live vaccines and non-irradiated blood products, should improve prognosis of SCID in our setting.


Asunto(s)
Inmunodeficiencia Combinada Grave/epidemiología , Edad de Inicio , Diagnóstico Tardío , Trasplante de Células Madre Hematopoyéticas , Humanos , Lactante , Recién Nacido , Montenegro/epidemiología , Tamizaje Neonatal , Diagnóstico Prenatal , Estudios Retrospectivos , Serbia/epidemiología , Inmunodeficiencia Combinada Grave/diagnóstico , Inmunodeficiencia Combinada Grave/terapia , Resultado del Tratamiento
11.
J Clin Microbiol ; 51(8): 2686-90, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23761151

RESUMEN

In immunocompromized patients, including hematopoietic stem cell transplant (HSCT) recipients, life-threatening toxoplasmosis may result from reactivation of previous infection. We report a case of severe disseminated toxoplasmosis that developed early after allogeneic HSCT for T-cell lymphoblastic leukemia/lymphoma in a 15-year-old Toxoplasma gondii-seropositive boy with Nijmegen breakage syndrome, a rare genetic DNA repair disorder associated with immunodeficiency. The donor was the patient's HLA-identical brother. Prophylaxis with cotrimoxazole was discontinued a day before the HSCT procedure. Signs of lung infection appeared as early as day 14 post-HSCT. The presence of tachyzoite-like structures on Giemsa-stained bronchoalveolar lavage (BAL) fluid smears suggested toxoplasmosis. Real-time PCR targeted at the T. gondii AF146527 gene revealed extremely high parasite burdens in both blood and BAL fluid. Although immediate introduction of specific treatment resulted in a marked reduction of the parasite load and transient clinical improvement, the patient deteriorated and died of multiple organ failure on day 39 post-HSCT. Direct genotyping of T. gondii DNA from blood and BAL fluid with the PCR-restriction fragment length polymorphism method revealed type II alleles with SAG1, SAG2, and GRA6 markers but alleles of both type I and type II with GRA7. Additional analysis with 15 microsatellite markers showed that the T. gondii DNA was atypical and genetically divergent from that of the clonal type I, II, and III strains. This is the first report of increased clinical severity of toxoplasmosis associated with an atypical strain in the setting of immunosuppression, which emphasizes the need to diagnose and monitor toxoplasmosis by quantitative molecular methods in cases of reactivation risk.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/efectos adversos , Huésped Inmunocomprometido , Toxoplasma/aislamiento & purificación , Toxoplasmosis/diagnóstico , Adolescente , Líquido del Lavado Bronquioalveolar/parasitología , Resultado Fatal , Genotipo , Humanos , Masculino , Neumonía/parasitología , Neumonía/patología , Proteínas Protozoarias/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Toxoplasma/clasificación , Toxoplasma/genética
12.
Infect Control Hosp Epidemiol ; 34(6): 597-604, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23651890

RESUMEN

OBJECTIVE: To report the results of a surveillance study on surgical site infections (SSIs) conducted by the International Nosocomial Infection Control Consortium (INICC). DESIGN: Cohort prospective multinational multicenter surveillance study. SETTING: Eighty-two hospitals of 66 cities in 30 countries (Argentina, Brazil, Colombia, Cuba, Dominican Republic, Egypt, Greece, India, Kosovo, Lebanon, Lithuania, Macedonia, Malaysia, Mexico, Morocco, Pakistan, Panama, Peru, Philippines, Poland, Salvador, Saudi Arabia, Serbia, Singapore, Slovakia, Sudan, Thailand, Turkey, Uruguay, and Vietnam) from 4 continents (America, Asia, Africa, and Europe). PATIENTS: Patients undergoing surgical procedures (SPs) from January 2005 to December 2010. METHODS: Data were gathered and recorded from patients hospitalized in INICC member hospitals by using the methods and definitions of the Centers for Disease Control and Prevention National Healthcare Safety Network (CDC-NHSN) for SSI. SPs were classified into 31 types according to International Classification of Diseases, Ninth Revision, criteria. RESULTS: We gathered data from 7,523 SSIs associated with 260,973 SPs. SSI rates were significantly higher for most SPs in INICC hospitals compared with CDC-NHSN data, including the rates of SSI after hip prosthesis (2.6% vs. 1.3%; relative risk [RR], 2.06 [95% confidence interval (CI), 1.8-2.4]; P < .001), coronary bypass with chest and donor incision (4.5% vs. 2.9%; RR, 1.52 [95% CI, 1.4-1.6]; [P < .001); abdominal hysterectomy (2.7% vs. 1.6%; RR, 1.66 [95% CI, 1.4-2.0]; P < .001); exploratory abdominal surgery (4.1% vs. 2.0%; RR, 2.05 [95% CI, 1.6-2.6]; P < .001); ventricular shunt, 12.9% vs. 5.6% (RR, 2.3 [95% CI, 1.9-2.6]; P < .001, and others. CONCLUSIONS: SSI rates were higher for most SPs in INICC hospitals compared with CDC-NHSN data.


Asunto(s)
Infección Hospitalaria/epidemiología , Vigilancia de la Población , Infección de la Herida Quirúrgica/epidemiología , Abdomen/cirugía , África/epidemiología , Artroplastia de Reemplazo de Cadera/efectos adversos , Asia/epidemiología , Puente de Arteria Coronaria/efectos adversos , Europa (Continente)/epidemiología , Humanos , Histerectomía/efectos adversos , Estudios Prospectivos , América del Sur/epidemiología , Infección de la Herida Quirúrgica/etiología , Derivación Ventriculoperitoneal/efectos adversos
13.
Radiat Prot Dosimetry ; 150(2): 213-6, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21990390

RESUMEN

A theoretical evaluation of the properties and processes affecting the radon transport from subsurface soil into buildings is presented in this work. The solution of the relevant transport equation is obtained using the explicit finite difference method (EFDM). Results are compared with analytical steady-state solution reported in the literature. Good agreement is found. It is shown that EFDM is effective and accurate for solving the equation that describes radon diffusion, advection and decay during its transport from subsurface to buildings, which is especially important when arbitrary initial and boundary conditions are required.


Asunto(s)
Vivienda , Modelos Teóricos , Análisis Numérico Asistido por Computador , Radón , Contaminantes Radiactivos del Suelo/análisis , Suelo
14.
Turk J Pediatr ; 52(4): 404-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21043387

RESUMEN

Neonatal tetanus is a severe, often fatal disease caused by the toxin Clostridium tetani. Neonatal tetanus is a generalized tetanus, which occurs in a neonate between 3-28 days of life. The findings indicated that tetanus in a newborn of an unvaccinated mother occurred after the application of non-sterile clay to the umbilical cord. This case was a seven-day-old male baby with progressive difficulty in feeding, trismus, hypertonicity, opisthotonos, and heart murmur. The patient was afebrile and eupneic, and had a history of non-sterile home delivery. In the past, the area of Bujanovac, Medvedja and Presevo had been exposed to mass immigration (especially due to the war in the territory of former Yugoslavia), which caused a serious problem for general practitioners, who had to be vigilant and ensure that all patients registered in their practice were fully immunized. This case has provided a clear indication of the necessity for strategies of both vaccination and ensuring hygienic conditions throughout pregnancy and delivery to prevent neonatal tetanus.


Asunto(s)
Tétanos/diagnóstico , Resultado Fatal , Humanos , Recién Nacido , Masculino , Factores de Riesgo , Serbia
15.
Pediatr Rheumatol Online J ; 8: 8, 2010 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-20181201

RESUMEN

We report on pediatric patient with clinical and laboratory evidence of pancreatitis at onset of atypical Kawasaki disease (KD). In KD pancreatic inflammation was described previously, but clinical pancreatitis was rarely reported and its true incidence is unknown.In febrile pediatric patients suspected to have KD, but not fulfilling classical diagnostic criteria, signs of pancreatic inflammation may help in making correct diagnosis. Further analysis of cases with atypical KD developing pancreatitis may reveal if signs of pancreatic inflammation can be used as supportive diagnostic finding.

16.
Acta Paediatr ; 98(6): 1062-4, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19243569

RESUMEN

UNLABELLED: We report different immunological phenotypes in three siblings from consanguineous family with recombinase-activating gene 1 (RAG1) gene mutations. Null mutations of RAG genes result in severe combined immunodeficiency (SCID) with absent T and B cells. Hypomorphic mutations with retained activity of RAG genes may lead to a 'leaky' SCID with some features of Omenn syndrome (OS) or typical OS. In our three patients, homozygous, hypomorphic RAG1 gene mutation (g.368-369delAA) was detected. Two patients presented with T-B-SCID phenotype while the youngest patient developed T+B+NK+SCID phenotype with expansion of autologous T-cell receptor (TCR) gammadelta-positive T cells, increased immunoglobulin levels and retained ability for antibody production. Similar to originally reported patients with this newly recognized immune phenotype, our patient developed disseminated cytomegalovirus (CMV) infection and autoimmune cytopenia. CONCLUSION: In infants with disseminated cytomegalovirus infection and autoimmune cytopenia, even if basic immunologic investigation appears normal, RAG1 immunodeficiency should be considered.


Asunto(s)
Genes RAG-1/genética , Mutación , Fenotipo , Inmunodeficiencia Combinada Grave/genética , Antígenos CD/sangre , Autopsia , Preescolar , Consanguinidad , Resultado Fatal , Femenino , Humanos , Lactante , Linfocitos/inmunología , Masculino , Inmunodeficiencia Combinada Grave/sangre , Inmunodeficiencia Combinada Grave/inmunología , Hermanos
17.
Med Phys ; 33(5): 1499-509, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16752584

RESUMEN

Indirect flat panel imagers have been developed for digital radiography, fluoroscopy and mammography, and are now in clinical use. Screens made from columnar structured cesium iodide (CsI) scintillators doped with thallium have been used extensively in these detectors. The purpose of this article is to investigate the effect of screen optics, e.g., light escape efficiency versus depth, on gain fluctuation noise, expressed as the Swank factor. Our goal is to obtain results useful in optimizing screens for digital radiography systems. Experimental measurements from structured CsI samples were used to derive their screen optics properties, and the same methods can also be applied to powder screens. CsI screens, all of the same thickness but with different optical designs and manufacturing techniques, were obtained from Hamamatsu Photonics Corporation. The pulse height spectra (PHS) of the screens were measured at different x-ray energies. A theoretical model was developed for the light escape efficiency and a method for deriving light escape efficiency versus depth from experimental PHS measurements was implemented and applied to the CsI screens. The results showed that the light escape efficiency varies essentially linearly as a function of depth in the CsI samples, and that the magnitude of variation is relatively small, leading to a high Swank factor.


Asunto(s)
Artefactos , Óptica y Fotónica/instrumentación , Intensificación de Imagen Radiográfica/instrumentación , Interpretación de Imagen Radiográfica Asistida por Computador/instrumentación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Procesamiento de Señales Asistido por Computador/instrumentación , Pantallas Intensificadoras de Rayos X , Algoritmos , Análisis de Falla de Equipo , Teoría Cuántica , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Med Phys ; 31(9): 2594-605, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15487742

RESUMEN

Columnar structured cesium iodide (CsI) scintillators doped with Thallium (Tl) have been used extensively for indirect x-ray imaging detectors. The purpose of this paper is to develop a methodology for systematic investigation of the inherent imaging performance of CsI as a function of thickness and design type. The results will facilitate the optimization of CsI layer design for different x-ray imaging applications, and allow validation of physical models developed for the light channeling process in columnar CsI layers. CsI samples of different types and thicknesses were obtained from the same manufacturer. They were optimized either for light output (HL) or image resolution (HR), and the thickness ranged between 150 and 600 microns. During experimental measurements, the CsI samples were placed in direct contact with a high resolution CMOS optical sensor with a pixel pitch of 48 microns. The modulation transfer function (MTF), noise power spectrum (NPS), and detective quantum efficiency (DQE) of the detector with different CsI configurations were measured experimentally. The aperture function of the CMOS sensor was determined separately in order to estimate the MTF of CsI alone. We also measured the pulse height distribution of the light output from both the HL and HR CsI at different x-ray energies, from which the x-ray quantum efficiency, Swank factor and x-ray conversion gain were determined. Our results showed that the MTF at 5 cycles/mm for the HR type was 50% higher than for the HL. However, the HR layer produces approximately 36% less light output. The Swank factor below K-edge was 0.91 and 0.93 for the HR and HL types, respectively, thus their DQE(0) were essentially identical. The presampling MTF decreased as a function of thickness L. The universal MTF, i.e., MTF plotted as a function of the product of spatial frequency f and CsI thickness L, increased as a function of L. This indicates that the light channeling process in CsI improved the MTF of thicker layers more significantly than for the thinner ones.


Asunto(s)
Cesio/efectos de la radiación , Análisis de Falla de Equipo/métodos , Cámaras gamma , Yoduros/efectos de la radiación , Intensificación de Imagen Radiográfica/instrumentación , Algoritmos , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Radiometría , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Rayos X
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