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We report an investigation of the structural, morphological, the ac-dc electrical, magnetic, and Mössbauer spectroscopy properties of 20MnFe2O4-80SiO2 nanocomposite prepared using a one-step and facile auto-combustion approach. XRD pattern shows the formation of MnFe2O4 nanocrystallite without any crystallization of the SiO2 phase. However, the presence of a secondary phase of the nanosized α-Fe2O3 particles was also detected. The morphological analysis showed aggregation of polygonal magnetic nano-crystallites dispersed non-uniformly in a silica matrix. The dc electrical measurements performed on a wide range of temperatures from 120 to 400 K showed the semiconducting nature of the nanocomposite. The temperature dependence of dc conductivity could be perfectly fitted to the nearest neighborhood hopping model with activation energy, ΔENNH, of 0.45 eV. The Nyquist plots demonstrated a nonmonotonous thermally activated trend and non-Debye relaxation behavior. An equivalent circuit was successfully fitted to the complex impedance spectra. The variation of both grain and grain boundary conductivities as a function of temperature exhibited three distinct regions, semiconducting-metallic-semiconducting with different activation energies over the measured temperature window. The provided description of such behavior is further advocated by the ac conductivity and dielectric modulus studies. VSM measurements revealed that the nanocomposite magnetic behavior deviates from the ideal non-interacting superparamagnetic picture, due to the presence of α-Fe2O3 nanocrystalline impurities and relatively intensive exchange interactions between ions. Mössbauer spectra showed the presence of Fe3+ ions with sixfold environment and also confirmed the existence of a sextet related to α-Fe2O3 with a quantity of about 20% out of magnetic components. Fe3+ superparamagnetic doublets were also found within the fitting procedure. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this paper is to demonstrate that a new algorithm for estimating arterial oxygen saturation can be effective even with data corrupted by motion artifacts (MAs). Methods: OxiMA, an algorithm based on the time-frequency components of a photoplethysmogram (PPG), was evaluated using 22-min datasets recorded from 10 subjects during voluntarily-induced hypoxia, with and without subject-induced MAs. A Nellcor OxiMax transmission sensor was used to collect an analog PPG while reference oxygen saturation and pulse rate (PR) were collected simultaneously from an FDA-approved Masimo SET Radical RDS-1 pulse oximeter. Results: The performance of our approach was determined by computing the mean relative error between the PR/oxygen saturation estimated by OxiMA and the reference Masimo oximeter. The average estimation error using OxiMA was 3 beats/min for PR and 3.24% for oxygen saturation, respectively. Conclusion: The results show that OxiMA has great potential for improving the accuracy of PR and oxygen saturation estimation during MAs. Significance: This is the first study to demonstrate the feasibility of a reconstruction algorithm to improve oxygen saturation estimates on a dataset with MAs and concomitant hypoxia. [ABSTRACT FROM AUTHOR]

Motion and noise artifacts (MNAs) impose limits on the usability of the photoplethysmogram (PPG), particularly in the context of ambulatory monitoring. MNAs can distort PPG, causing erroneous estimation of physiological parameters such as heart rate (HR) and arterial oxygen saturation (SpO2). In this study, we present a novel approach, “TifMA,” based on using the time–frequency spectrum of PPG to first detect the MNA-corrupted data and next discard the nonusable part of the corrupted data. The term “nonusable” refers to segments of PPG data from which the HR signal cannot be recovered accurately. Two sequential classification procedures were included in the TifMA algorithm. The first classifier distinguishes between MNA-corrupted and MNA-free PPG data. Once a segment of data is deemed MNA-corrupted, the next classifier determines whether the HR can be recovered from the corrupted segment or not. A support vector machine (SVM) classifier was used to build a decision boundary for the first classification task using data segments from a training dataset. Features from time–frequency spectra of PPG were extracted to build the detection model. Five datasets were considered for evaluating TifMA performance: (1) and (2) were laboratory-controlled PPG recordings from forehead and finger pulse oximeter sensors with subjects making random movements, (3) and (4) were actual patient PPG recordings from UMass Memorial Medical Center with random free movements and (5) was a laboratory-controlled PPG recording dataset measured at the forehead while the subjects ran on a treadmill. The first dataset was used to analyze the noise sensitivity of the algorithm. Datasets 2-4 were used to evaluate the MNA detection phase of the algorithm. The results from the first phase of the algorithm (MNA detection) were compared to results from three existing MNA detection algorithms: the Hjorth, kurtosis-Shannon entropy, and time-domain variability-SVM approaches. This last is an approach recently developed in our laboratory. The proposed TifMA algorithm consistently provided higher detection rates than the other three methods, with accuracies greater than 95% for all data. Moreover, our algorithm was able to pinpoint the start and end times of the MNA with an error of less than 1 s in duration, whereas the next-best algorithm had a detection error of more than 2.2 s. The final, most challenging, dataset was collected to verify the performance of the algorithm in discriminating between corrupted data that were usable for accurate HR estimations and data that were nonusable. It was found that on average 48% of the data segments were found to have MNA, and of these, 38% could be used to provide reliable HR estimation. [ABSTRACT FROM AUTHOR]

The sol-gel method is a very flexible route for producing sieving matrix such as SiO2 with pore radii in nanoscale region to embed oxide particles like Fe2O3. In this work, iron oxide nanoparticles embedded in a SiO2 glassy matrix prepared by the sol-gel method have been investigated as a function of Fe/Si ratio. Different composition of dried gels with 1, 2, 10 and 20 mol% of Fe2O3 in the SiO2 matrix were heat-treated (HT) in air, at temperatures from 400 ºC up to 1400 °C. The structure and morphology of the obtained glasses and glass-ceramics were studied by X-ray powder diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). Impedance spectroscopy measurements and magnetic characterization were performed as function of temperature and the results are related with the microstructure. The X-ray diffraction patterns showed that increasing the amount of Fe2O3 oxide promotes the formation of crystalline phases, in particular silicate phases. The increase of the heat-treatment temperature has a similar behavior. The electrical and dielectric properties were related with these structural modifications and with the sample morphology. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Ni- and Fe-doped CeO2 nanoparticles were prepared by a chemical co-precipitation method and then heat treated at 300 °C. The structural, morphological, and compositional properties of the prepared nanoparticles were studied by powder X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS), Scanning Electron Microscopy (SEM) and Fourier-Transform Infrared (FT-IR) Spectroscopy. The powder XRD results revealed that all the samples exhibit the typical cubic fluorite structure of CeO2. The EDS and FTIR analyses confirmed the formation of CeO2 nanoparticles and the incorporation of Fe and Ni ions in the crystal lattice of CeO2. The photoluminescence (PL) properties were investigated to assess the effect of Fe- and Ni-doping on the emission properties of CeO2 nanoparticles. The impacts of the type of dopant on the dielectric properties and ac conductivity of the prepared nanoparticles were investigated. It was observed that the dielectric constant of Ni-doped CeO2 nanoparticles measured at low-frequency region is much greater than that of Fe-doped CeO2 nanoparticles. The difference was explained on the basis of interfacial/space charge polarization, with Ni-doped CeO2 nanoparticles having a more heterogeneous dielectric structure. The universal Jonscher power law was well adjusted to the ac conductivity spectra. It was shown that the Fe-CeO2 composite nanoparticles are less conductive than the Ni-doped CeO2 ones. [ABSTRACT FROM AUTHOR]

Objective: To report a novel phenotype of negative myoclonus in acute post-anoxic brain injury (PABI)., Methods: We performed a retrospective analysis of 18-channel video-EEG and surface-EMG (sEMG) recordings of three patients with PABI. sEMG electrodes were placed on the neck, bulbar and arm muscles., Results: All three patients had whole body tonic posturing with intermittent brief relaxation. In patients #1 and #2, a generalized EEG burst-suppression was present. Repetitive silent periods (SPs) were noted in the sEMG channels, time-locked to EEG bursts. The bursts preceded the SPs by 135 ms and 124 ms, respectively. The average SP duration was 910 ms and 852 ms in patients #1 and 2, respectively. Patient #3 had a generalized background suppression pattern and average SP duration of 272.5 ms. The SP recruitment pattern in patient #1 was rostro-caudal whereas patient #3 had a variable recruitment pattern., Conclusion: Acute post-anoxic negative myoclonus can be detected in comatose patients with sEMG electrodes. The muscle SPs produce intermittent relaxation of the tonic posturing. The putative generator can be cortical or reticular, similar to Lance-Adams syndrome., Significance: We describe a novel phenotype of negative myoclonus in acute PABI. We also describe the EEG and sEMG characteristics and the localization of the putative generator., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Background: Type 2 diabetes mellitus (T2DM) is recognized as a complex metabolic which has affected the lives of millions of people around the world. Vitamin D receptor (VDR) gene polymorphisms have been suggested to be a vital contributor to the development of T2DM. However, the association between VDR gene polymorphisms and T2DM remains controversial. We have investigated the association between two VDR gene polymorphisms (rs731236 and rs1544410) and T2DM in an Iranian population., Methods: A total of 148 T2DM patients and 100 normal controls were recruited in this study. We used polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis to perform genotyping., Results: The results of the present research revealed that the frequency of the rs731236 C allele was significantly higher in T2DM patients than in normal controls (p = 0.044). The CC genotype of rs731236 was connected with an increased risk of T2DM (OR = 2.85, 95% CI = 1.06-7.69, p = 0.039). However, no significant difference in the frequency of the rs1544410 C allele between T2DM patients and normal controls was observed (p = 0.918)., Conclusion: Our findings were suggestive of the rs731236 polymorphism of the VDR as a risk factor for developing T2DM in the Iranian population, while rs1544410 polymorphism may not be associated with T2DM susceptibility. Further research is needed to approve these findings in other populations and to clarify the underlying mechanisms involved in such an association., Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-023-01323-0., Competing Interests: Competing of interestThere are no conflicts of interest declared by the authors., (© The Author(s), under exclusive licence to Tehran University of Medical Sciences 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Background: Stroke is the leading cause of mortality. This study aimed to investigate the association between stroke, comorbidities, and activity of daily living (ADL) among older adults in the United States., Methods: Participants were 1165 older adults aged 60 and older from two waves (2016 and 2018) of the Health and Retirement Study who had a stroke. Descriptive statistics were used to describe demographic information and comorbidities. Logistic regressions and multiple regression analyses were used to determine associations between stroke, comorbidities, and ADL., Results: The mean age was 75.32 ± 9.5 years, and 55.6% were female. An adjusted analysis shows that older stroke adults living with diabetes as comorbidity are significantly associated with difficulty in dressing, walking, bedding, and toileting. Moreover, depression was significantly associated with difficulty in dressing, walking, bathing, eating, and bedding. At the same time, heart conditions and hypertension as comorbidity were rarely associated with difficulty in ADL. After adjusting for age and sex, heart condition and depression are significantly associated with seeing a doctor for stroke (odds ratio [OR]: 0.66; 95% confidence interval [CI]: 0.49-0.91;  p  = 0.01) and stroke therapy (OR: 0.46; 95% CI: 0.25-0.84;  p  = 0.01). Finally, stroke problem (unstandardized β [ B ] = 0.58, p  = 0.017) and stroke therapy ( B  = 1.42, p  < 0.001) significantly predict a lower level of independence., Conclusion: This study could benefit healthcare professionals in developing further interventions to improve older stroke adults' lives, especially those with a high level of dependence., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Chronic Diseases and Translational Medicine published by John Wiley & Sons Ltd on behalf of Chinese Medical Association.)

The present work proposes an ultrasound (US) assisted electro-Fenton (EF) process for eliminating penicillin G (PNG) and ciprofloxacin (CIP) from aqueous solutions and the process was further optimized by response surface methodology (RSM)- Box-Behnken design (BBD). The impact of pH, hydrogen peroxide (H 2 O 2 ) concentration, applied voltage, initial pollutant concentration, and operating time were studied. The capability application of the electro-Fenton (EF) and US processes was compared separately and in combination under the optimum conditions of pH of 4, a voltage of 15 V, the initial antibiotic concentration of 20.7 mg/L, H 2 O 2 concentration of 0.8 mg/L, and the operating time of 75 min. The removal efficiency of PNG and CIP using the sono-electro-Fenton (SEF) process, as the results revealed, was approximately 96% and 98%, respectively. The experiments on two scavengers demonstrated that ⦁ OH contributes significantly to the CIP and PNG degradation by SEF, whereas ⦁ O - 2 corresponds to only a negligible amount. The total organic carbon (TOC) and chemical oxygen demand (COD) analyses were used to assess the mineralization of CIP and PNG. The efficiency of COD and TOC removal was reached at 73.25% and 62.5% for CIP under optimized operating circumstances, and at 61.52% and 72% for PNG, respectively. These findings indicate that a sufficient rate of mineralization was obtained by SEF treatment for the mentioned pollutants. The reaction kinetics of CIP and PNG degradation by the SEF process were found to follow a pseudo-first-order kinetic model. In addition, the human health risk assessment of natural water containing CIP and PNG that was purified by US, EF, and SEF processes was done for the first time. According to the findings, the non-carcinogenic risk (HQ) caused by drinking purified water by all three systems was calculated in the acceptable range. Thus, SEF is a proper system to remove various antibiotics in potable water and reduces their human health risks., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Anti-leucine-rich glioma-inactivated 1 encephalitis is a newly emerged entity characterized by frequent faciobrachial dystonic seizures and a wide spectrum of subacute clinical symptoms such as other seizure types, mood and behavioral changes, and memory loss. We should be aware of differentiating this diagnosis from psychogenic nonepileptic seizures. Mesial temporal, limbic structures, and basal ganglia are the most commonly involved regions., Case Presentation: Here we review the available data, and report on two young Iranian (White) females, 24 and 18 years old, who represent distinct aspects of the disease. The clinical presentation and degree of tissue involvement varies to some extent in the two reported cases. Case 1 had prominent neuropsychiatric symptoms and suffered from frequent faciobrachial dystonic seizures with more significant basal ganglia involvement, whereas case 2 suffered from severe memory decline and dialeptic seizures along with mesial temporal involvement. Symptoms were refractory to usual treatment and prompt immunotherapy was needed., Conclusions: This disease has a rather favorable outcome provided that treatment is initiated early. However, resistance to first-line treatment, relapses, and long-term complications highlight the need to establish reliable biomarkers to distinguish different subtypes of this disorder to predict the clinical outcome and prognosis, and to refine management., (© 2022. The Author(s).)

Background: The present study aimed to address the effect of Rituximab on the cognitive impairment in patients with secondary progressive MS (SPMS)., Methods: The present interventional study used a convenience sampling method to select the study participants from SPMS patients. All these patients had progressive disability over the last two years before being admitted in the study. Prior to the administration of Rituximab, the minimal assessment of cognitive function in the multiple sclerosis (MACFIMS) test was performed for each patient who was a candidate to be included in this study. This test was repeated by passing 6 and 12 months from the initial treatment with Rituximab. Since the data needed for this study were obtained at different time intervals, so a linear mixed model was used for their analysis. Analysis of variance (ANOVA) was also used to investigate whether time and sex generally affect the cognitive impairments in SPMS patients. A p-value <0.05 was considered as statistically significant in this study., Results: Of the total 35 patients, 34% and 66% were men and women with a mean age of 41.33 and 41.39 years old, respectively. Rituximab showed a significant positive effect on a number of subgroups of MACFIMS test, including Controlled Oral Word Association Test (COWAT) (P-value: 0.038) and Brief Visuospatial Memory Test (BVMT-total) (P: 0.019)., Conclusion: The present study revealed that Rituximab has a positive effect on the cognitive impairment resulted from MS in secondary progressive patients., Competing Interests: Abdorreza Naser Moghadasi and Mohammad Ali Sahraian have received speaker’s honoraria from AryoGen Pharmed. The other authors do not have any conflict of interest.

Introduction/aims: Objective outcome measures to monitor treatment response and guide treatment are lacking in chronic inflammatory demyelinating polyneuropathy (CIDP). In this study we aimed to evaluate the motor unit number index (MUNIX) as an outcome measurement in patients with CIDP and determine the correlation of MUNIX with functional and standard electrodiagnostic tests in a single follow-up study., Methods: We evaluated MUNIX of the abductor pollicis brevis, abductor digiti minimi, and tibialis anterior (TA) muscles bilaterally. Muscle force was assessed by Medical Research Council Sum Score (MRCSS). Functional measures used were the Overall Neuropathy Limitation Score (ONLS) and the Rasch-built Overall Disability Scale (R-ODS) score at baseline and after 6 months of treatment. Standard electrophysiology was evaluated by the Nerve Conduction Study Score (NCSS)., Results: Twenty patients were included at baseline, and 16 completed the follow-up study. Significant correlations were found between the MUNIX sum score and both MRCSS and NCSS at baseline, between both the pinch strength and grip and upper limb MUNIX at baseline and follow-up, and between MUNIX of TA and both lower limb MRCSSs with lower limb ONLS at baseline and follow-up. Significant correlations also were found between MUNIX sum score change and MRCSS change, R-ODS change, and ONLS change., Discussion: MUNIX changes correlated with strength and electrophysiological improvements in CIDP patients. This suggests that MUNIX may represent a useful objective biomarker for patient follow-up., (© 2022 Wiley Periodicals LLC.)

[Figure: see text].

Competing Interests: Conflict of interest The author declares that there is no conflict of interest.

Background: Evans syndrome is an uncommon autoimmune disorder manifested by fatigue, jaundice, pallor, purpura and petechiae. The main characteristics of this rare disease are simultaneous or sequential existence of positive anti-globulin test, immune thrombocytopenia (ITP) and autoimmune hemolytic anemia (AIHA). Evans syndrome as an autoimmune disorder can be associated with other diseases. The concomitancy of Evans syndrome and multiple sclerosis (MS) has not been reported so far. In this case study, a -21-year old male with concomitant Evans syndrome and MS has been reported., Case Presentation: A 21-year-old male of Iranian origin and known case of Evans syndrome, was referred to our hospital for better evaluation. Evans syndrome was presented with acute jaundice, purpura, petechiae, and easy bruising when he was 9.He was under treatment of corticosteroid and cytotoxic agents, and presented with left lower extremity paresis for 5 months before admission to our hospital. According to neuroimaging and pathologic results, multiple sclerosis (MS) was diagnosed. Hence, we decided to treat the patient with rituximab. The patient has been stable without any further exacerbation or increase in disability progression after 2 years from diagnosis., Conclusion: Evans syndrome can be associated with other autoimmune disorders. For our case, we have reported this association with MS.

A BaCO 3 /BaSnO 3 /SnO 2 nanocomposite has been prepared using a co-precipitation method without adding any additives. The prepared sample was characterized by using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, energy dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. Detailed studies on the dielectric and electrical behavior (dielectric constant, complex impedance Z *, ac conductivity, and relaxation mechanisms) of the nanocomposite have been performed using the nondestructive complex impedance spectroscopy technique within the temperature range 150-400 K. The dielectric constant of the sample as a function of temperature showed the typical characteristics of a relaxor. The maximum dielectric constant value was observed to depend on frequency. The non-monotonic relaxation behavior of the prepared nanocomposite was evidenced from the spectra of loss tan, tan( δ ). The relaxation kinetics was modeled using a non-Arrhenius model., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Motion and noise artifacts (MNAs) impose limits on the usability of the photoplethysmogram (PPG), particularly in the context of ambulatory monitoring. MNAs can distort PPG, causing erroneous estimation of physiological parameters such as heart rate (HR) and arterial oxygen saturation (SpO2). In this study, we present a novel approach, "TifMA," based on using the time-frequency spectrum of PPG to first detect the MNA-corrupted data and next discard the nonusable part of the corrupted data. The term "nonusable" refers to segments of PPG data from which the HR signal cannot be recovered accurately. Two sequential classification procedures were included in the TifMA algorithm. The first classifier distinguishes between MNA-corrupted and MNA-free PPG data. Once a segment of data is deemed MNA-corrupted, the next classifier determines whether the HR can be recovered from the corrupted segment or not. A support vector machine (SVM) classifier was used to build a decision boundary for the first classification task using data segments from a training dataset. Features from time-frequency spectra of PPG were extracted to build the detection model. Five datasets were considered for evaluating TifMA performance: (1) and (2) were laboratory-controlled PPG recordings from forehead and finger pulse oximeter sensors with subjects making random movements, (3) and (4) were actual patient PPG recordings from UMass Memorial Medical Center with random free movements and (5) was a laboratory-controlled PPG recording dataset measured at the forehead while the subjects ran on a treadmill. The first dataset was used to analyze the noise sensitivity of the algorithm. Datasets 2-4 were used to evaluate the MNA detection phase of the algorithm. The results from the first phase of the algorithm (MNA detection) were compared to results from three existing MNA detection algorithms: the Hjorth, kurtosis-Shannon entropy, and time-domain variability-SVM approaches. This last is an approach recently developed in our laboratory. The proposed TifMA algorithm consistently provided higher detection rates than the other three methods, with accuracies greater than 95% for all data. Moreover, our algorithm was able to pinpoint the start and end times of the MNA with an error of less than 1 s in duration, whereas the next-best algorithm had a detection error of more than 2.2 s. The final, most challenging, dataset was collected to verify the performance of the algorithm in discriminating between corrupted data that were usable for accurate HR estimations and data that were nonusable. It was found that on average 48% of the data segments were found to have MNA, and of these, 38% could be used to provide reliable HR estimation.

Background: Hepatitis B infection is a universal concern. This infection can lead to chronic liver disease and hepatocellular carcinoma. Neonates born to HBsAg-positive mothers are at high risk of chronic hepatitis B virus (HBV) infection, especially for HBeAg-positive mothers or neonates who have not received hepatitis B immunoglobulin (HBIg) and HBV vaccines., Objectives: The aim of this study was to evaluate the efficacy of post-exposure prophylaxis in these infants to prevent infection., Patients and Methods: Thirty-eight infants born to HBsAg-positive mothers between September 2006 and September 2013 were followed. The investigation evaluated whether the standard prevention protocol of neonatal HBV transmission including HBIg at birth and receiving three doses of vaccine at birth and 2 and 6 months of age was performed, followed by post-vaccination tests (evaluation of HBsAg and HBsAb titer at 9 to 18 months of age) to determine subsequent infection. HBsAb titer ≥ 10 was considered as criterion for effectiveness of the prophylaxis procedure. The acquired data were analyzed using SPSS software (Version 18). The results are reported in descriptive tabulations., Results: Ninety seven percent (97%) of infants received HBIg at birth in the hospital. Generally, all of them received the first, second and third doses of vaccine at birth, 2 months, and 6 months after birth, respectively. Information for 35 mothers infected with HBV and 38 infants was available. The mean age of the mothers was 30.3 years. The results indicated that 20% of mothers were HBeAg positive. HBsAg was positive in one (2.6%) infant born to an HBeAg-positive mother. Around 94% of infants' HBsAb titers were ≥ 10, and 5.8% were reported as non-responders., Conclusions: The vertical transmission prevention program used in the study population in Tehran, which had an appropriate sample size, is effective. Additional doses of the vaccine can be useful in raising the effectiveness of immunoprophylaxis for infants at high risk of HBV infection. Also, emphasis must be set on post-vaccination testing.

Purpose: The aim of this study was to assess the relative frequency of peripheral odontogenic fibroma (POdF) in an Iranian population and to compare the obtained data with previous reports., Materials and Methods: Archival material was retrospectively analyzed from 1967 to 2007, and all microscopic slides of lesions considered in the differential diagnosis of POdF were retrieved. A diagnosis of POdF was made according to the criteria described by the World Health Organization in 2005. Demographic data, including age, gender, site of involvement, and previous history of POdF, were recorded for all samples with a diagnosis of this neoplasm., Results: Nineteen POdFs were identified, which accounted for 0.14% of the archival cases. One of these tumors was a recurrence, diagnosed 12 months earlier. All cases were of the epithelium-rich or World Health Organization histologic subtype and most tumors occurred in the mandible. No significant difference in the prevalence of POdF was found between the studied variables. Among the 18 primary neoplasms, follow-up was possible for 2 to 13 years in 6 cases, and none developed recurrence., Conclusion: Similar to previous investigations, this study shows that POdFs are uncommon odontogenic lesions. Detailed information on POdF is limited because of its rarity; therefore, this study may provide additional data for further investigations and may enable better understanding of this tumor., (Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)