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1.
Proc Natl Acad Sci U S A ; 120(7): e2212256120, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36745794

RESUMEN

The distribution of brain aerobic glycolysis (AG) in normal young adults correlates spatially with amyloid-beta (Aß) deposition in individuals with symptomatic and preclinical Alzheimer disease (AD). Brain AG decreases with age, but the functional significance of this decrease with regard to the development of AD symptomatology is poorly understood. Using PET measurements of regional blood flow, oxygen consumption, and glucose utilization-from which we derive AG-we find that cognitive impairment is strongly associated with loss of the typical youthful pattern of AG. In contrast, amyloid positivity without cognitive impairment was associated with preservation of youthful brain AG, which was even higher than that seen in cognitively unimpaired, amyloid negative adults. Similar findings were not seen for blood flow nor oxygen consumption. Finally, in cognitively unimpaired adults, white matter hyperintensity burden was found to be specifically associated with decreased youthful brain AG. Our results suggest that AG may have a role in the resilience and/or response to early stages of amyloid pathology and that age-related white matter disease may impair this process.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Adulto Joven , Humanos , Enfermedad de Alzheimer/patología , Tomografía de Emisión de Positrones , Encéfalo/metabolismo , Péptidos beta-Amiloides/metabolismo , Disfunción Cognitiva/patología , Amiloide/metabolismo , Proteínas Amiloidogénicas , Glucólisis
2.
Neuroimage ; 285: 120494, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38086495

RESUMEN

White matter hyperintensities (WMH) are nearly ubiquitous in the aging brain, and their topography and overall burden are associated with cognitive decline. Given their numerosity, accurate methods to automatically segment WMH are needed. Recent developments, including the availability of challenge data sets and improved deep learning algorithms, have led to a new promising deep-learning based automated segmentation model called TrUE-Net, which has yet to undergo rigorous independent validation. Here, we compare TrUE-Net to six established automated WMH segmentation tools, including a semi-manual method. We evaluated the techniques at both global and regional level to compare their ability to detect the established relationship between WMH burden and age. We found that TrUE-Net was highly reliable at identifying WMH regions with low false positive rates, when compared to semi-manual segmentation as the reference standard. TrUE-Net performed similarly or favorably when compared to the other automated techniques. Moreover, TrUE-Net was able to detect relationships between WMH and age to a similar degree as the reference standard semi-manual segmentation at both the global and regional level. These results support the use of TrUE-Net for identifying WMH at the global or regional level, including in large, combined datasets.


Asunto(s)
Leucoaraiosis , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Algoritmos , Envejecimiento
3.
J Am Chem Soc ; 145(50): 27316-27324, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38055597

RESUMEN

High and increasing production of separation of C8 aromatic isomers demands the development of purification methods that are efficient, scalable, and inexpensive, especially for p-xylene, PX, the largest volume C8 commodity. Herein, we report that 4-(1H-1,2,4-triazol-1-yl)-phenyl-1H-benzo[de]isoquinoline-1,3(2H)-dione (TPBD), a molecular compound that can be prepared and scaled up via solid-state synthesis, exhibits exceptional PX selectivity over each of the other C8 isomers, o-xylene (OX), m-xylene (MX), and ethylbenzene (EB). The apohost or α form of TPBD was found to exhibit conformational polymorphism in the solid state enabled by rotation of its triazole and benzene rings. TPBD-αI and TPBD-αII are nonporous polymorphs that transformed to the same PX inclusion compound, TPBD-PX, upon contact with liquid PX. TPBD enabled highly selective capture of PX, as established by competitive slurry experiments involving various molar ratios in binary, ternary, and quaternary mixtures of C8 aromatics. Binary selectivity values for PX as determined by 1H NMR spectroscopy and gas chromatography ranged from 22.4 to 108.4, setting new benchmarks for both PX/MX (70.3) and PX/EB (59.9) selectivity as well as close to benchmark selectivity for PX/OX (108.4). To our knowledge, TPBD is the first material of any class to exhibit such high across-the-board PX selectivity from quaternary mixtures of C8 aromatics under ambient conditions. Crystallographic and computational studies provide structural insight into the PX binding site in TPBD-PX, whereas thermal stability and capture kinetics were determined by variable-temperature powder X-ray diffraction and slurry tests, respectively. That TPBD offers benchmark PX selectivity and facile recyclability makes it a prototypal molecular compound for PX purification or capture under ambient conditions.

4.
J Magn Reson Imaging ; 57(3): 952-961, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36054250

RESUMEN

BACKGROUND: Despite technological advancements in perinatal imaging, autopsy examination is still regarded as the reference standard to determine the time and reason of the fetal death. PURPOSE: This study was conducted to identify the intrauterine postmortem magnetic resonance imaging (PMMR) findings of fetuses, who underwent radiofrequency ablation (RFA). STUDY TYPE: Prospective. POPULATION: Fifty-three twin/triplet complicated pregnancies scheduled for selective reduction of one of the fetuses by RFA were included. FIELD STRENGTH/SEQUENCE: The imaging methods used are T1-weighted gradient-echo imaging (T1 GRE), T2 half-Fourier acquisition single-shot turbo spin-echo (SSTSE), and diffusion-weighted imaging (DWI) sequences. ASSESSMENT: The MRIs were interpreted by three radiologists. STATISTICAL TESTS: Data were analyzed using the software package SPSS Statistics Version 22.0. The used tests included one-way analysis of variance (ANOVA) and Duncan tests (significance level: P value <0.05). This analysis was performed with scikit-learn library (version 1.1.1) in Python version 3.9. RESULTS: Average PMMR scores of orbit, brain, and abdomen showed significant differences among different PM interval subgroups. The brain apparent diffusion coefficient (ADC) numbers of reduced and living fetuses were significantly different at any PM interval. To determine which findings are closely associated with the timing of fetal death, five different methods of feature selection were employed. The top eight selected features achieved the highest area under the curve (AUC) of 78.19%. DATA CONCLUSION: In utero, PMMR findings may be associated with the time of fetal death. Among different fetal organs evaluated, particularly PMMR top eight features specifically scores of orbits were associated with PM intrauterine time after death. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Muerte Fetal , Feto , Embarazo , Femenino , Humanos , Autopsia , Estudios Prospectivos , Feto/diagnóstico por imagen , Muerte Fetal/etiología , Imagen por Resonancia Magnética/efectos adversos , Imagen de Difusión por Resonancia Magnética/métodos , Embarazo Múltiple
5.
BMC Pediatr ; 22(1): 557, 2022 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-36131275

RESUMEN

BACKGROUND/SIGNIFICANCE: Salmonella gastroenteritis causes significant morbidity among pediatric patients, mainly in developing world, such as the Middle East and North Africa (MENA) region. Concurrently, data from MENA countries like Iran, regarding prevalence of Salmonella serotypes, antimicrobial susceptibility, and biofilm production is scarce. MATERIAL & METHODS: Slide agglutination was used to determine the serogroup of 140 Salmonella isolates recovered from 4477 stool specimens collected from children with gastroenteritis, and isolates were serotyped by PCR assay. The antimicrobial susceptibility of isolates to five first line drugs was assessed by disk diffusion assay using CLSI guidelines. Semi-quantitative evaluation of biofilm production was done by microtiter plate assay followed by PCR detection of biofilm-associated virulence genes csgD, pefA, and bcsA for each isolate. RESULTS: Nearly 94% of Salmonella isolates were recovered from ≤ 5-year-old patients, and 99% of isolates were non-typhoidal. While we found extensive diversity among Salmonella isolates, serogroup D (46%) predominated, and Salmonella Enteritidis (41%) was the most common serotype that showed the highest antimicrobial susceptibility rate (> 96%). For the first time in Iran, S. Newport serotype from human specimens was isolated. Most isolates were sensitive to all test antimicrobials, but 35% of isolates were not-typed (NT) that showed the highest resistance with 48% being resistant to ≥ 1 test antimicrobial. Majority of isolates made weak (or no) biofilm, and we found a weak association between antimicrobial susceptibility, biofilm production, or virulence genes csgD, pefA, and bcsA. CONCLUSIONS: The most effective measure that may control pediatric salmonellosis outbreaks is raising awareness of parents of preschoolers about food safety. Isolation of highly diverse Salmonella serotypes, including many commonly isolated from animals, indicates widespread contamination of the food chain. Majority of serotypes were sensitive to first-line antimicrobials, thus presently, pediatric Salmonella infections in this region may be controlled by conventional antimicrobials. However, despite the current trend, an imminent emergence of resistant Salmonella strains is foreseen, since various serotypes resistant to > 1 antimicrobial agent are typically associated with animals. Our results warrant further investigation that includes correlation analysis of clinical data regarding treatment outcomes, and serotype attributes like virulence genes.


Asunto(s)
Antiinfecciosos , Gastroenteritis , Infecciones por Salmonella , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Biopelículas , Niño , Preescolar , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana Múltiple/genética , Humanos , Irán/epidemiología , Pruebas de Sensibilidad Microbiana , Salmonella/genética , Infecciones por Salmonella/tratamiento farmacológico , Infecciones por Salmonella/epidemiología , Serogrupo , Virulencia/genética
6.
Neurochem Res ; 45(2): 221-231, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31782101

RESUMEN

The brain-derived neurotrophic factor (BDNF) mediates the plasticity-related changes that associate with memory processing during sleep. Sleep deprivation and chronic stress are associated with propensity to depression, anxiety, and insomnia. We propose a model by which explain alterations in the CNS and serum expression of BDNF associated with chronic sleep deprivation, depression, and insomnia. Mild sleep deprivation activates the cerebral cortex and brainstem to generate the physiologic drive for non-rapid eye movement (NREM) and rapid eye movement (REM) sleep drive respectively, associated with BDNF upregulation in these regions. This physiological response loses effectiveness with longer episodes or during chronic of total or selective REM sleep loss, which are associated with impaired hippocampal BDNF expression, impaired memory and cognition. Chronic sleep deprivation and insomnia can act as an external stressors and result in depression, characterized by hippocampal BDNF downregulation along with disrupted frontal cortical BDNF expression, as well as reduced levels and impaired diurnal alterations in serum BDNF expression. Acute REM sleep deprivation breaks the cycle by restoration of hippocampal, and possibly restoration of cortical and serum expression of BDNF. The BDNF Val66Met polymorphism alters susceptibility to depression, anxiety, and insomnia by altering availability and expression of BDNF in brain and blood. The proposed model is testable and implies that low levels and low variability in serum BDNF are associated with poor response to anti-depressive medications, electroconvulsive therapy, and REM sleep deprivation, in patients with depression. Our mode is also backed up by the existing clinical evidence but is yet to be investigated.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Depresión/fisiopatología , Privación de Sueño/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Depresión/genética , Hipocampo/metabolismo , Humanos , Polimorfismo de Nucleótido Simple , Privación de Sueño/genética , Trastornos del Inicio y del Mantenimiento del Sueño/genética , Sueño REM/fisiología
7.
Croat Med J ; 60(5): 405-413, 2019 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-31686454

RESUMEN

AIM: To determine whether serum ferritin, liver transaminases, and regularity and type of iron chelation protocol can be used to predict liver iron load as assessed by T2* magnetic resonance imaging (MRI) in patients with beta thalassemia major (TM). METHODS: This cross-sectional study, conducted from March 1, 2014 to March 1, 2015, involved 90 patients with beta TM on regular packed red blood cell transfusion. Liver and cardiac iron load were evaluated with T2* MRI. Compliance with iron-chelating agents, deferoxamine or deferasirox, and regularity of their use, as well as serum ferritin and liver transaminase levels were assessed. RESULTS: Patients with high serum ferritin were 2.068 times (95% confidence interval 1.26-3.37) more likely to have higher liver or cardiac iron load. High serum aspartate aminotransferases and irregular use of iron chelating agents, but not their type, predicted higher cardiac iron load. In a multiple regression model, serum ferritin level was the only significant predictor of liver and myocardial iron load. CONCLUSIONS: Higher serum ferritin strongly predicted the severity of cardiac and liver iron load. Irregular use of chelator drugs was associated with a higher risk of cardiac and liver iron load, regardless of the type of chelating agent.


Asunto(s)
Ferritinas/sangre , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro , Talasemia beta , Estudios Transversales , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/complicaciones , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/terapia , Hígado/química , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Cumplimiento de la Medicación/estadística & datos numéricos , Talasemia beta/sangre , Talasemia beta/complicaciones , Talasemia beta/epidemiología , Talasemia beta/terapia
8.
Med J Islam Repub Iran ; 31: 50, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29445679

RESUMEN

Background: Cervical cancer is the second most common type of cancer among women. Effective screening programs can help cancer detection in early phases and reduce death. Metastasis to lymph nodes is one of the most prognostic factors in patients who underwent surgery. Also, a positive result from pathology report alert oncologist as a cause of death. Sentinel lymph node biopsy has been widely studied and clinically used for many types of cancer. Methods: Two techniques exist for detecting sentinel node in cervical cancer, which are Blue dye and gamma probe with radioactive isotope (99mTc). Moreover, lymphoscintigraphy has many advantages over the stain method. Detecting the sentinel node is performed via laparoscopy or laparotomy; former method is better and more accurate. Results: Various researchers have focused on this method and its positive results; its superiority against full lymphadenectomy has been declared in previous studies. Moreover, the role of sentinel lymph nodes biopsy in cervical cancer is still being extensively studied. Sentinel lymph nodes (SLN) method has a higher accuracy level to detect metastasis. Conclusion: Hence, it can be considered as a more appropriate alternative for pelvic lymph node dissection (PLND), which is a standard technique. Altering the method to a standard clinical method needs in-depth researches and studies.

9.
Asian Pac J Cancer Prev ; 25(4): 1265-1270, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38679986

RESUMEN

PURPOSE: This study aims to compare the accuracy of the ADNEX MR scoring system and pattern recognition system to evaluate adnexal lesions indeterminate on the US exam. METHODS: In this cross-sectional retrospective study, pelvic DCE-MRI of 245 patients with 340 adnexal masses was studied based on the ADNEX MR scoring system and pattern recognition system. RESULTS: ADNEX MR scoring system with a sensitivity of 96.6% and specificity of 91% has an accuracy of 92.9%. The pattern recognition system's sensitivity, specificity, and accuracy are 95.8%, 93.3%, and 94.7%, respectively. PPV and NPV for the ADNEX MR scoring system were 85.1 and 98.1, respectively. PPV and NPV for the pattern recognition system were 89.7% and 97.7%, respectively. The area under the ROC curve for the ADNEX MR scoring system and pattern recognition system is 0.938 (95% CI, 0.909-0.967) and 0.950 (95% CI, 0.922-0.977). Pairwise comparison of these AUCs showed no significant difference (p = 0.052). CONCLUSION: The pattern recognition system is less sensitive than the ADNEX MR scoring system, yet more specific.


Asunto(s)
Enfermedades de los Anexos , Imagen por Resonancia Magnética , Humanos , Femenino , Estudios Transversales , Estudios Retrospectivos , Persona de Mediana Edad , Enfermedades de los Anexos/diagnóstico por imagen , Enfermedades de los Anexos/patología , Enfermedades de los Anexos/diagnóstico , Adulto , Imagen por Resonancia Magnética/métodos , Anciano , Pronóstico , Curva ROC , Estudios de Seguimiento , Adolescente , Adulto Joven , Reconocimiento de Normas Patrones Automatizadas/métodos , Anexos Uterinos/patología , Anexos Uterinos/diagnóstico por imagen
10.
Br J Radiol ; 97(1153): 150-158, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263830

RESUMEN

OBJECTIVES: Dynamic contrast-enhanced (DCE) MRI is not available in all imaging centres to investigate adnexal masses. We proposed modified magnetic resonance (MR) scoring system based on an assessment of the enhancement of the solid tissue on early phase postcontrast series and diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) map and investigated the validity of this protocols in the current study. MATERIALS AND METHODS: In this cross-sectional retrospective study, pelvic MRI of a total of 245 patients with 340 adnexal masses were studied based on the proposed modified scoring system and ADNEX MR scoring system. RESULTS: Modified scoring system with the sensitivity of 87.3% and specificity of 94.6% has an accuracy of 92.1%. Sensitivity, specificity, and accuracy of ADNEX MR scoring system is 96.6%, 91%, and 92.9%, respectively. The area under the receiver operating characteristic curve for the modified scoring system and ADNEX MR scoring system is 0.909 (with 0.870-0.938 95% confidence interval [CI]) and 0.938 (with 0.907-0.961 95% CI), respectively. Pairwise comparison of these area under the curves showed no significant difference (P = .053). CONCLUSIONS: Modified scoring system is less sensitive than the ADNEX MR scoring system and more specific but the accuracy is not significantly different. ADVANCES IN KNOWLEDGE: According to our study, MR scoring system based on subjective assessment of the enhancement of the solid tissue on early phase postcontrast series and DWI with ADC map could be applicable in imaging centres that DCE is not available.


Asunto(s)
Imagen por Resonancia Magnética , Ovario , Humanos , Femenino , Estudios Transversales , Estudios Retrospectivos , Espectroscopía de Resonancia Magnética
11.
J Biosci Med (Irvine) ; 11(2): 177-185, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36945328

RESUMEN

Alzheimer's disease (AD) is a brain disorder that eventually causes memory loss and the ability to perform simple cognitive functions; research efforts within pharmaceuticals and other medical treatments have minimal impact on the disease. Our preliminary biological studies showed that Repeated Electromagnetic Field Stimulation (REFMS) applying an EM frequency of 64 MHz and a specific absorption rate (SAR) of 0.4 - 0.9 W/kg decrease the level of amyloid-ß peptides (Aß), which is the most likely etiology of AD. This study emphasizes uniform E/H field and SAR distribution with adequate penetration depth penetration through multiple human head layers driven with low input power for safety treatments. In this work, we performed numerical modeling and computer simulations of a portable Meander Line antenna (MLA) to achieve the required EMF parameters to treat AD. The MLA device features a low cost, small size, wide bandwidth, and the ability to integrate into a portable system. This study utilized a High-Frequency Simulation System (HFSS) in the design of the MLA with the desired characteristics suited for AD treatment in humans. The team designed a 24-turn antenna with a 60 cm length and 25 cm width and achieved the required resonant frequency of 64 MHz. Here we used two numerical human head phantoms to test the antenna, the MIDA and spherical head phantom with six and seven tissue layers, respectively. The antenna was fed from a 50-Watt input source to obtain the SAR of 0.6 W/kg requirement in the center of the simulated brain tissue layer. We found that the E/H field and SAR distribution produced was not homogeneous; there were areas of high SAR values close to the antenna transmitter, also areas of low SAR value far away from the antenna. This paper details the antenna parameters, the scattering parameters response, the efficiency response, and the E and H field distribution; we presented the computer simulation results and discussed future work for a practical model.

12.
Skeletal Radiol ; 41(3): 281-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21479858

RESUMEN

BACKGROUND: Patients with carpal tunnel syndrome (CTS) have a variety of vasomotor symptoms. Here, we aimed to study the vasomotor activity of the radialis indicis (RI) artery (median nerve territory) and the radial palmar digital (RPD) artery of the little finger (ulnar nerve territory) before and after sympathetic stimulation in CTS patients using color Doppler ultrasound. METHODS: We performed a cross-sectional study of 46 consecutive CTS patients plus 36 healthy controls. All patients underwent electromyography studies and were classified into mild and moderate/severe groups according to electrodiagnostic findings. Color Doppler examination of the RI artery and the RPD artery of the little finger were performed with the participants in a relaxed sitting position and after a deep breath followed by a cough (sympathetic stimulation). The pulsatility index (PI) was recorded at the point of maximal change in waveform, before and after this stimulus. RESULTS: The PI of RI artery was significantly lower (p < 0.01) in CTS patients than healthy controls, both before and after stimulation. The changes in PI of RI artery after stimulation were significantly lower in CTS patients than healthy controls (1.18 ± 0.37 vs. 5.41 ± 0.87; p < 0.001). The same pattern was seen for PI of RI artery when comparing patients with mild vs. moderate/severe CTS. No difference was found in PI of RPD artery of the 5th finger between patients vs. controls and between patients with mild vs. moderate/severe CTS, both before and after stimulation. CONCLUSIONS: We showed that color Doppler ultrasound can readily determine impaired vasomotor activity in CTS patients.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico por imagen , Síndrome del Túnel Carpiano/fisiopatología , Mano/fisiopatología , Nervio Mediano/fisiopatología , Ultrasonografía Doppler en Color/métodos , Sistema Vasomotor/diagnóstico por imagen , Sistema Vasomotor/fisiopatología , Velocidad del Flujo Sanguíneo , Femenino , Mano/diagnóstico por imagen , Humanos , Masculino , Nervio Mediano/diagnóstico por imagen , Persona de Mediana Edad , Flujo Sanguíneo Regional , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
Iran J Nurs Midwifery Res ; 27(6): 531-537, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36712306

RESUMEN

Background: Cognitive disorders are one of the most common disorders in elderly people with chronic renal failure. This study aimed to investigate the correlation and agreement of Montreal Cognitive Assessment (MoCA), Abbreviated Mental Test Score (AMTS), and Mini-Mental State Examination (MMSE) tests in assessing the cognitive status of elderly patients undergoing hemodialysis at Guilan University of Medical Sciences in north of Iran. Materials and Methods: This cross-sectional study was conducted on 84 elderly people undergoing hemodialysis. Inclusion criteria was having an age of 60 years old and older, hemodialysis treatment for at least 6 months, and having reading and writing skills. The Pearson correlation test, Intraclass Correlation Coefficient (ICC) test, and Bland-Altman plot were used for data analysis. Results: The majority of samples were in the age group of 60-65 years (28.57%) and the majority of them were male (66.66%). The results showed a significant positive correlation between MoCA and MMSE (r = 0.69, p = 0.001), between MMSE and AMTS (r = 0.64, p = 0.001), and between MoCA and AMTS tests (r = 0.62, p = 0.001). The results also showed a weak agreement between MoCA and MMSE tests (ICC = -0.11, p = 0.633), between MMSE and AMTS tests (ICC = -0.007, p = 0.369), and between MoCA and AMTS tests (ICC = -0.001, p = 0.780). Conclusions: Based on the results, these tools seem to complement each other. The inconsistency between cognitive tests indicates a serious need to develop appropriate instruments for detecting cognitive disorders in elderly.

14.
Iran J Parasitol ; 17(4): 497-505, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36694568

RESUMEN

Background: Cryptosporidium spp. are protozoan parasites that cause diarrhea in humans and animals. Subtyping data about Cryptosporidium spp. in Isfahan, Iran is limited; therefore, we aimed to study the prevalence rate of Cryptosporidium spp. in cancer patients, associated risk factors, and subtypes of Cryptosporidium spp. Methods: Fecal samples were collected from 187 cancer patients from the Oncology Department of Seyed-al-Shohada Hospital, Isfahan University of Medical Sciences during 2014-2020 and screened for Cryptosporidium spp. using microscopical techniques. Nested PCR amplifying 18S rRNA gene was used to detect Cryptosporidium spp. in samples, followed by subtyping using nested PCR amplifying gp60 sequences. Results: Overall, the rate of infection with Cryptosporidium spp. was 4.3% (n=8). Five samples out of eight samples were identified as Cryptosporidium spp. using a nested PCR for the 18S rRNA gene, two subtypes of C. parvum named IIaA18G3R1 (n = 2) and IIaA17G2R1 (n = 2), and one subtype of C. hominis named IbA6G3 were identified by sequencing of the gp60. The IbA6G3 subtype has rarely been detected in other investigations. Conclusion: This is the first survey on the subtyping of Cryptosporidium spp. in this region. The results of the present survey show both zoonotic and anthroponotic transmission routes in the region.

15.
Pharmaceutics ; 14(11)2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36365138

RESUMEN

Crystal engineering of multi-component molecular crystals, cocrystals, is a subject of growing interest, thanks in part to the potential utility of pharmaceutical cocrystals as drug substances with improved properties. Whereas molecular cocrystals (MCCs) are quite well studied from a design perspective, ionic cocrystals (ICCs) remain relatively underexplored despite there being several recently FDA-approved drug products based upon ICCs. Successful cocrystal design strategies typically depend on strong and directional noncovalent interactions between coformers, as exemplified by hydrogen bonds. Understanding of the hierarchy of such interactions is key to successful outcomes in cocrystal design. We herein address the crystal engineering of ICCs comprising azole functional groups, particularly imidazoles and triazoles, which are commonly encountered in biologically active molecules. Specifically, azoles were studied for their propensity to serve as coformers with strong organic (trifluoroacetic acid and p-toluenesulfonic acid) and inorganic (hydrochloric acid, hydrobromic acid and nitric acid) acids to gain insight into the hierarchy of NH+···N (azolium-azole) supramolecular heterosynthons. Accordingly, we combined data mining of the Cambridge Structural Database (CSD) with the structural characterization of 16 new ICCs (11 imidazoles, 4 triazoles, one imidazole-triazole). Analysis of the new ICCs and 66 relevant hits archived in the CSD revealed that supramolecular synthons between identical azole rings (A+B-A) are much more commonly encountered, 71, than supramolecular synthons between different azole rings (A+B-C), 11. The average NH+···N distance found in the new ICCs reported herein is 2.697(3) Å and binding energy calculations suggested that hydrogen bond strengths range from 31-46 kJ mol-1. The azolium-triazole ICC (A+B-C) was obtained via mechanochemistry and differed from the other ICCs studied as there was no NH+···N hydrogen bonding. That the CNC angles in imidazoles and 1,2,4-triazoles are sensitive to protonation, the cationic forms having larger (approximately 4.4 degrees) values than comparable neutral rings, was used as a parameter to distinguish between protonated and neutral azole rings. Our results indicate that ICCs based upon azolium-azole supramolecular heterosynthons are viable targets, which has implications for the development of new azole drug substances with improved properties.

16.
Probiotics Antimicrob Proteins ; 14(6): 1139-1150, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35585423

RESUMEN

Enterococci act as symbionts in human gastrointestinal tract. The present study aimed to evaluate the characteristics of fecal enterococci isolated from infants and adults, and to compare them to the known probiotic bacteria, including lactobacilli species and E. faecalis Symbioflor 1. In total, sporadic distribution of virulence genes was detected among the studied enterococci. Furthermore, the frequency of genes encoding for sex pheromones (ccf and cob), collagen adhesion (ace), cell wall adhesion (efaAfs), and gelatinase (gelE) was observed to be significantly higher in those isolates obtained from infants compared to those obtained from adults. Although the ability of biofilm formation was found in all isolates, the strong biofilm formation was observed in enterococci from infants and strong correlation was observed between the capacities to form biofilm and attachment to Caco-2 cells. Cell-free culture supernatant showed some inhibitory effects on indicator strains, which were related to the production of organic acids (against P. aeruginosa and enteropathogenic E. coli) or both organic acids and proteinaceous antimicrobial agents (against L. monocytogenes and E. faecalis). Approximately, 79% and 71% of the isolates showed strong inhibitory effects on P. aeruginosa and L. monocytogenes, respectively. Unlike lactobacilli, enterococcal cell-free supernatants had no toxicity on intestinal cells. In conclusion, this study shows that some enterococcal isolates obtained from fecal microbiota have characteristics, which are comparable with the known probiotic bacteria. Therefore, these isolates should be considered to find probiotic candidate. The proteinaceous identity of antimicrobial substances derived from these isolates highlighted the probable contribution of bacteriocins into this issue.


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Humanos , Enterococcus , Células CACO-2 , Escherichia coli , Factores de Virulencia/genética , Antibacterianos/farmacología , Enterococcus faecalis
17.
J Biomed Sci Eng ; 15(8): 219-227, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36032690

RESUMEN

In this study, we performed a numerical analysis of a novel EMF Birdcage wearable device for the treatment of Alzheimer's disease (AD). We designed the new device to generate and radiate a frequency of 64 MHz and a specific absorption rate (SAR) of 0.6 W/kg to a simulated human brain tissue. We determined these parameters from our experimental studies on primary human brain cultures at the Indiana University School of Medicine (IUSM). We found that this frequency and SAR decreased the toxic Aß levels in the cell cultures. The frequency of 64 MHZ has good skin depth penetration, which will easily pass through the various head layers, including hair, skin, fat, dura, the cerebrospinal (CSF), and grey matter, and reach deeply into the brain tissues. The SAR of 0.6 W/kg was achieved with lower power input and energy, decreasing the probability of thermal injury. Therefore, these parameters enhance the safety of these potential treatments. This Birdcage device emulates a small-scale MRI machine, producing the same 64 MHz frequency at much lower operating input power. In this work, we utilized a high-frequency simulation system (HFSS/EMPro) software to produce the birdcage structure for the required EMF parameters. The 64 MHz radiating frequency produced the scattering S11 parameter of -15 dbs. We obtained a SAR of 0.6 W/kg when an input power of 100 W was applied. The coil dimensions were found to be near 15 cm in height and 22 cm in diameter, which fits in wearable systems. We found that the distribution of the electric field and SAR radiate homogeneously over the simulated human head with good penetration into the brain, which proves to be an appropriate potential therapeutic strategy for Alzheimer's disease.

18.
Cancer Treat Res Commun ; 31: 100559, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35460974

RESUMEN

BACKGROUND: This study aimed to investigate the potential relationship between diffusion kurtosis imaging (DKI)- derived parameters and lymphovascular space invasion (LVSI) in patients with cervical carcinoma. PATIENTS AND METHODS: This prospective study included 30 patients with cervical carcinoma. The patients underwent MRI, diffusion-weighted imaging (DWI), and DKI prior to surgery. The surgical pathology results were accepted as the reference standard for determining the LVSI status. The DKI-derived parameters, including mean diffusivity (MD) and mean kurtosis (MK), were measured. The apparent diffusion coefficient (ADC) value was also assessed. RESULTS: The MD value of LVSI positive cervical carcinomas was significantly lower than LVSI negative carcinomas (p-value = 0.01). MK value was significantly higher in LVSI positive tumors (p-value = 0.01). However, the ADC value did not show a significant difference between LVSI positive and LVSI negative tumors (p-value = 0.2). MD and MK parameters showed similar diagnostic accuracy in identifying the LVSI status, with the area under the curve of 0.77 and 0.78, respectively. CONCLUSION: In this study, DKI-derived parameters were associated with the LVSI status in cervical carcinomas. Further studies with larger sample size are required to confirm these results.


Asunto(s)
Carcinoma , Neoplasias del Cuello Uterino , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Estudios Prospectivos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/patología
19.
J Biomed Sci Eng ; 15(5): 129-139, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35663520

RESUMEN

In this paper, we follow up with our preliminary biological studies that showed that Repeated electromagnetic field stimulation (REMFS) decreased the toxic amyloid-beta (Aß) levels, which is considered to be the cause of Alzheimer's disease (AD). The REMFS parameters of these exposures were a frequency of 64 MHz and a Specific absorption rate (SAR) of 0.4 to 0.9 W/Kg in primary human neuronal cultures. In this work, an electromagnetic field (EMF) model was simulated using high-frequency simulation system (HFSS/EMPro) software. Our goal was to achieve the EM parameters (EMF Frequency and SAR) required to decrease the toxic Aß levels in our biological studies in a simulated human head. The simulations performed here will potentially lead to the successful development of an exposure system to treat Alzheimer's disease patients. A popular VFH (very high frequency) patch microstrip antenna system was considered in the study. The selection was based on simple and easy construction and appropriateness to the VHF applications. The evaluation of the SAR and temperature distribution on the various head layers, including skin, fat, dura, the cerebrospinal (CSF), and grey matter, brain tissues, were determined for efficacy SAR and safety temperature increase on a simulated human head. Based on a current pulse of 1 A peak current fed to the antenna feeder, a maximum SAR of 0.6 W/Kg was achieved. A range of 0.4 to 0.6 SAR was observed over the various layers of the simulated human head. The initial design of the antenna indicated an antenna size in the order of 1 m in length and width, suggesting a stationary practical model for AD therapy. Future direction is given for wearable antenna and exposure system, featuring high efficiency and patient comfort.

20.
Radiology ; 261(2): 499-506, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21900619

RESUMEN

PURPOSE: To determine whether intraneural vascularity seen at color Doppler ultrasonography (US) can be used to diagnose carpal tunnel syndrome (CTS) and to evaluate an image processing method for quantifying the severity of CTS on the basis of this vascularity. MATERIALS AND METHODS: This study was approved by the university ethics review committee. One hundred one patients with clinical evidence of CTS and 55 healthy control subjects were enrolled. Electrodiagnostic testing (EDT) was performed in all participants, and the presence of intraneural vascularity was evaluated with color Doppler US. An image processing program was designed by using software to determine the sum of pixels in the intraneural vascular area on power Doppler US scans of the median nerve. The relationship between the number of pixels and the severity of the abnormality at EDT was determined. RESULTS: The sensitivity (83%) and specificity (89%) of intraneural vascularity in the diagnosis of CTS were similar to those of EDT (81% and 84%, respectively). Intraneural vascularity was seen in 91.4% of patients with mild CTS and 100% of patients with moderate or severe CTS. In participants with positive intraneural vascularity, the sum of pixels in the intraneural vascular area was significantly higher in patients than in control subjects and paralleled the severity of the abnormality at EDT (P < .01). CONCLUSION: Color Doppler US can be used to accurately diagnose CTS. By processing the recorded power Doppler images and determining the number of pixels in the intraneural vascular area, the severity of CTS can be assessed. 2011 SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11110150/-/DC1.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador , Nervio Mediano/irrigación sanguínea , Nervio Mediano/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Adulto , Anciano , Estudios de Casos y Controles , Estudios Transversales , Electrodiagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Ultrasonografía Doppler en Color
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