Primary intraosseous papillary intralymphatic angioendothelioma of the distal femoral epiphysis: a case report with literature review.

INTRODUCTION: Papillary intralymphatic angioendothelioma (PILA) is an exceptionally rare metastasizing soft tissue tumor. It tends to arise in the subcutaneous tissues of distal extremities in children. Only four intraosseous PILA cases have been reported until now in English language literature. CASE REPORT: We present a case of PILA arising in the distal femoral epiphysis of a 50-year-old female patient. It started as a relentless pain in her left knee. A plain radiography revealed a radiolucent area in the left internal femoral condyle. Computerized tomography revealed a 1-cm lytic lesion with a sclerotic rim. Magnetic resonance images showed a significant bone marrow edema signal focused on a 1-cm subchondral lesion suggestive of an intraarticular osteoid osteoma. Histologically, the tumor contained vascular channels covered by a single endothelial layer with intraluminal papillary endothelial structures lined with hobnail cells. Immunohistochemically, the cells were positive for ERG, CD31, and D2-40. The tumor underwent cryoablation and 6 months later, after local recurrence or tumor persistence, a wide tumor resection was referred. After 7 years of follow-up, the patient displayed neither local recurrence nor distant metastases. CONCLUSION: Primary intraosseous PILAs are exceedingly rare tumors that should be considered in the differential diagnosis of vascular bone tumors.

AEDV Expert Consensus for the Management of Syphilis. / Documento de expertos de la AEDV para el manejo de la sífilis.

Syphilis -the "great simulator" for classical venereologists-is re-emerging in Western countries despite adequate treatment; several contributing factors have been identified, including changes in sexual behaviour, which won't be the topic of this article though. In 2021, a total of 6613 new cases of syphilis were reported in Spain, representing an incidence of 13.9×100 000 inhabitants (90.5%, men). Rates have increased progressively since 2000. The clinical presentation of syphilis is heterogeneous. Although chancroid, syphilitic roseola and syphilitic nails are typical lesions, other forms of the disease can be present such as non-ulcerative primary lesions like Follmann balanitis, chancres in the oral cavity, patchy secondary lingual lesions, or enanthema on the palate and uvula, among many others. Regarding diagnosis, molecular assays such as PCR have been replacing dark-field microscopy in ulcerative lesions while automated treponemal tests (EIA, CLIA) are being used in serological tests, along with classical tests (such as RPR and HAART) for confirmation and follow-up purposes. The interpretation of these tests should be assessed in the epidemiological and clinical context of the patient. HIV serology and STI screening should be requested for anyone with syphilis. Follow-up of patients under treatment is important to ensure healing and detect reinfection. Serological response to treatment should be assessed with the same non-treponemal test (RPR/VDRL); 3-, 6-, 12-, and 24-month follow-up is a common practice in people living with HIV (PLHIV). Sexual contacts should be assessed and treated as appropriate. Screening is advised for pregnant women within the first trimester of pregnancy. Pregnant women with an abortion after week 20 should all be tested for syphilis. The treatment of choice for all forms of syphilis, including pregnant women and PLHIV, is penicillin. Macrolides are ill-advised because of potential resistance.

Analysis of co-isogenic prion protein deficient mice reveals behavioral deficits, learning impairment, and enhanced hippocampal excitability.

BACKGROUND: Cellular prion protein (PrPC) is a cell surface GPI-anchored protein, usually known for its role in the pathogenesis of human and animal prionopathies. However, increasing knowledge about the participation of PrPC in prion pathogenesis contrasts with puzzling data regarding its natural physiological role. PrPC is expressed in a number of tissues, including at high levels in the nervous system, especially in neurons and glial cells, and while previous studies have established a neuroprotective role, conflicting evidence for a synaptic function has revealed both reduced and enhanced long-term potentiation, and variable observations on memory, learning, and behavior. Such evidence has been confounded by the absence of an appropriate knock-out mouse model to dissect the biological relevance of PrPC, with some functions recently shown to be misattributed to PrPC due to the presence of genetic artifacts in mouse models. Here we elucidate the role of PrPC in the hippocampal circuitry and its related functions, such as learning and memory, using a recently available strictly co-isogenic Prnp0/0 mouse model (PrnpZH3/ZH3). RESULTS: We performed behavioral and operant conditioning tests to evaluate memory and learning capabilities, with results showing decreased motility, impaired operant conditioning learning, and anxiety-related behavior in PrnpZH3/ZH3 animals. We also carried in vivo electrophysiological recordings on CA3-CA1 synapses in living behaving mice and monitored spontaneous neuronal firing and network formation in primary neuronal cultures of PrnpZH3/ZH3 vs wildtype mice. PrPC absence enhanced susceptibility to high-intensity stimulations and kainate-induced seizures. However, long-term potentiation (LTP) was not enhanced in the PrnpZH3/ZH3 hippocampus. In addition, we observed a delay in neuronal maturation and network formation in PrnpZH3/ZH3 cultures. CONCLUSION: Our results demonstrate that PrPC promotes neuronal network formation and connectivity. PrPC mediates synaptic function and protects the synapse from excitotoxic insults. Its deletion may underlie an epileptogenic-susceptible brain that fails to perform highly cognitive-demanding tasks such as associative learning and anxiety-like behaviors.

Primary aneurysmal bone cyst of hands and feet: A series of 14 cases.

Aneurysmal bone cyst (ABC) is a relatively rare, benign bone tumor that occurs exceptionally in the hands and feet. The objective of this article is to present clinical, radiological, histopathological features and management of a series of 14 primary ABC cases in these unusual locations. Eight cases occurred in hands and six in feet. We present the first reported subungual case to occur in the hand. The average age of the patients was 26 years (range 7 to 49), with half being over the age of twenty at diagnosis. The male to female ration was 9:5. In radiological terms, ABC appeared as an expansive lesion with internal septa and without cortical disruption. Twelve cases displayed the classic multicystic morphology and two cases were of the solid variant. "Blue bone" was detected in 50 % of the specimens. Treatment consisted of curettage, excision, or amputation in all cases. Recurrence rate was observed in 35 % of the cases, with the similar ABC morphology as the original samples. New therapeutic options have been proposed on their own or in combination with surgery to reduce local recurrence rates.

Transcriptional analysis of nasal polyps fibroblasts reveals a new source of pro-inflammatory signaling in CRSwNP.

BACKGROUND: Fibroblasts and others mesenchymal cells have recently been identified as critical cells triggering tissue-specific inflammatory responses. Persistent activation of fibroblasts inflammatory program has been suggested as an underlying cause of chronic inflammation in a wide range of tissues and pathologies. Nevertheless, the role of fibroblasts in the emergence of chronic inflammation in the upper airway has not been previously addressed. We aimed to elucidate whether fibroblasts could have a role in the inflammatory response in chronic rhinosinusitis with nasal polyps (CRSwNP). METHODOLOGY: We performed whole-transcriptome microarray in fibroblast cultured from CRSwNP samples and confirmed our results by qRT-PCR. We selected patients without other associated diseases in upper airway. To investigate shifts in transcriptional profile we used fibroblasts from nasal polyps and uncinate mucosae from patient with CRSwNP, and fibroblasts from uncinate mucosae from healthy subjects as controls. RESULTS: This study exposes activation of a pro-inflammatory and pro-fibrotic transcriptional program in nasal polyps and CRSwNP fibroblasts when compared to controls. Our Gene-set Enrichment Analysis (GSEA) pointed to common up-regulation of several pro-inflammatory pathways in patients-derived fibroblasts, along with higher mRNA expression levels of cytokines, growth factors and extracellular matrix components. CONCLUSIONS: Our work reveals a potential new source of inflammatory signaling in CRSwNP. Furthermore, our results suggest that deregulated inflammatory signaling in tissue-resident fibroblasts could support a Type-2 inflammatory response. Further investigations will be necessary to demonstrate the functionality of these novel results.

[Pulmonary CT angiography in the first wave of the COVID-19 pandemic: comparison between patients with and without infection and with a pre-pandemic series]. / Angio-TC pulmonar durante la pandemia de COVID-19: comparación en pacientes con y sin la infección y con una serie prepandémica.

Background and aims: To analyze the diagnostic performance of pulmonary CT angiography and to compare different D-dimer cutoffs for the diagnosis of acute pulmonary embolism in patients with and without SARS-CoV-2 infections. Materials and methods: We retrospectively analyzed all consecutive pulmonary CT angiography studies done for suspected pulmonary embolism in a tertiary hospital during two time periods: the first December 2020 through February 2021 and the second December 2017 through February 2018. D-dimer levels were obtained less than 24 hours before the pulmonary CT angiography studies. We analyzed the sensitivity, specificity, positive and negative predictive values, area under the receiver operating curve (AUC), and pattern of pulmonary embolism for six different values of D-dimer and the extent of the embolism. During the pandemic period, we also analyzed whether the patients had COVID-19. Results: After excluding 29 poor-quality studies, 492 studies were analyzed; 352 of these were done during the pandemic, 180 in patients with COVID-19 and 172 in patients without COVID-19. The absolute frequency of pulmonary embolism diagnosed was higher during the pandemic period (34 cases during the prior period and 85 during the pandemic; 47 of these patients had COVID-19). No significant differences were found in comparing the AUCs for the D-dimer values. The optimum values calculated for the receiver operating characteristic curves differed between patients with COVID-19 (2200 mcg/L), without COVID-19 (4800 mcg/L), and diagnosed in the prepandemic period (3200 mcg/L). Peripheral distribution of the emboli was more common in patients with COVID-19 (72%) than in those without COVID-19 and than in those diagnosed before the pandemic [OR 6.6, 95% CI:1.5?24.6, p< 0.05 when compared to central distribution]. Conclusions: The number of CT angiography studies and the number of pulmonary embolisms diagnosed during the pandemic increased due to SARS-CoV-2 infection. The optimal D-dimer cutoffs and the distribution of the pulmonary embolisms differed between the groups of patients with and without COVID-19.

High Levels of Heavy Metals detected in Feathers of an Avian Scavenger Warn of a High Pollution Risk in the Atacama Desert (Chile).

The Atacama Desert represents the highest levels of mining exploitation in Chile, which inexorably results in high levels of pollution. Raptors, and particularly scavengers, have shown their usefulness to evaluate exposure to environmental contaminants in polluted scenarios. In this study, we used primary feathers from a local avian scavenger, turkey vulture Cathartes aura, to evaluate the exposure to cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) in two locations from the southern Atacama Desert (coastal and inland) and a third location from the bordering semiarid region, in northern Chile. All metals were detected in all analyzed samples (n = 54). Mean concentrations in Coastal Atacama were 0.68 ± 0.84 ppm for Cd; 1.97 ± 2.01 ppm for Pb; 59.11 ± 80.69 ppm for Cu; and 107.96 ± 51.00 ppm for Zn, while mean concentrations in Inland Atacama were 0.55 ± 0.42 ppm for Cd; 3.37 ± 2.61 ppm for Pb; 91.66 ± 77.74 ppm for Cu; and 214.03 ± 99.08 ppm for Zn. Mean concentrations in Coastal Coquimbo were 0.63 ± 0.69 ppm for Cd; 1.57 ± 0.92 ppm for Pb; 18.09 ± 6.12 ppm for Cu; and 149.37 ± 105.56 ppm for Zn. These differences could be explained by differences on abundance of mining settlements among areas. According to the literature, these values are very high for all metals, exceeding in some cases those values referred as responsible of health disorders in birds. We strongly recommend further research looking at potential adverse effects caused by heavy metal pollution on the health of human and wildlife populations in the southern Atacama Desert.

The mechanochemical synthesis of PbTe nanostructures: following the Ostwald ripening effect during milling.

A fundamental understanding of the Ostwald ripening effect (ORE) during the mechanochemical synthesis of PbTe nanostructures is presented. The ripening process involves the coarsening of larger particles from those of smaller size; this phenomenon was systematically evaluated at different stages of milling by microscopy analyses (AFM, TEM, STEM and HRTEM). At the early stage of milling, smaller particles and quantum dots are eventually dissolved to lower the total energy assciated with their surfaces. The ripening process - during milling - involves short-range mass transfer among particles. HRTEM analyses allowed us to identify that coarsening occurs by thermo-mechanically activated cooperative mechanisms. The detachment of the atoms from smaller particles to form bigger ones plays a major role in the particle coarsening. It was found that the coarsening process was not limited to crystalline nanostructures; so grain boundaries, edge dislocations and boundaries among crystalline and amorphous phases also play an important role to determine how species migration contributes to generate coarse particles. Those serve as sites for inducing coarsening in an equivalent way as surfaces do. Secondary ion mass spectrometry and elemental chemical mapping (EDX-STEM) revealed that both the purity and the chemical homogeneity of the PbTe nanostructures are prominent features of this material. Additionally, a direct band gap enhancement (780 nm) compared to bulk PbTe (3859 nm) was detected. It occurred due to the quantum confinement effect, lattice imperfections and even surface properties of the nanostructures. It is important to point out that the whole optical behaviour of the PbTe nanostructures was dependent upon the embedded nanoparticles and quantum dots in the clusters and coarse particles ranging from 15 nm to 35 nm.

Appropriateness of magnetic resonance imaging requested by primary care physicians for patients with knee pain.

OBJECTIVE: To evaluate the appropriateness of magnetic resonance imaging (MRI) of the knee requested by primary care physicians. DESIGN: Retrospective observational study. SETTING: Six primary care centres in the Elche Department of Health of the Valencian Community, Spain. PARTICIPANTS: Three hundred patients with knee pain who were prescribed MRI. MAIN OUTCOME MEASURES: Data were collected from the electronic clinical history, which allowed us to assess the appropriateness and inappropriateness of the MRI requests for the knee based on the American College of Radiology (ACR) criteria. A multivariate logistic regression model was used to identify factors associated with an inappropriate request. RESULTS: About 45% (41-49%) of knee MRI prescriptions were assessed as inappropriate. The frequency was higher in female patients (odds ratio, OR = 1.96; P = 0.03). A history of knee trauma and urgent use of MRI were associated with a lower frequency of inappropriate requests (OR = 0.14, P < 0.001 and OR = 0.32, P = 0.03, respectively). In 82% of cases, the request for MRI was deemed inappropriate because it was used as the initial imaging test. The availability of a previous radiograph of the knee significantly reduced the rate of inappropriate requests (OR = 0.05, P < 0.001); only 47% of the patients had a previous radiograph. CONCLUSIONS: The percentage of inappropriate knee MRI prescriptions is high. Protocols should be put in place to improve the appropriateness of MRI requests by promoting understanding of the appropriate use of MRI among primary care physicians.

Clinical and immunological profile of children aged 5-9 years with persistent egg allergy before oral immunotherapy with egg. A multicenter, randomized controlled trial of the Spanish Society of Pediatric Allergy, Asthma and Clinical Immunology (SEICAP).

BACKGROUND: In children with egg protein allergy (EA), the probability of overcoming the allergy decreases with age, and the possibility of suffering severe adverse reactions as a consequence of dietetic transgressions results in worsened quality of life. One treatment option in such cases is oral immunotherapy (OIT) with foods. METHODS: We present a cohort of children with EA scheduled for OIT with pasteurized raw egg white, describing their clinical and allergic characteristics before the start of OIT. RESULTS: The median age was six years, and 93% of the patients also suffered other allergies (58% asthma and 38.6% allergy to more than two food groups). In the last year, 14.8% had suffered a severe reaction due to dietetic transgression with egg. The median IgE specific of egg white titer was 38.5kU/l. A double-blind placebo-controlled food challenge with cooked egg white was performed, and if the test proved positive, it was repeated with pasteurized raw egg white. The mean symptoms-provoking dose was 1.26g and 0.55g for cooked egg white and raw egg white, respectively. An IgE specific of ovomucoid titer of <2.045kU/l differentiated those patients that tolerated cooked egg white. CONCLUSIONS: OIT with egg is regarded as an option in patients with persistent egg allergy. In the previous challenge test, an IgE specific of ovomucoid titer of <2.045kU/l differentiates those patients that tolerate cooked egg white.

FXa inhibition by rivaroxaban modifies mechanisms associated with the pathogenesis of human abdominal aortic aneurysms.

AIMS: To evaluate if rivaroxaban, an oral factor Xa (FXa) inhibitor, could modify the expression in vitro of inflammatory and oxidative stress biomarkers in abdominal aortic aneurysmal (AAA) sites showing intraluminal thrombus. METHODS: AAA sites with intraluminal mural thrombus were obtained from six patients undergoing elective AAA repair. In addition, control abdominal aortic samples were obtained from six organ donors. AAA sites were incubated in the presence and absence of 50 nmol l-1 rivaroxaban. RESULTS: AAA sites showing thrombus demonstrated higher content of FXa than control. Interleukin-6 levels released from AAA [Control: median: 23.45 (interquartile range: 16.17-37.15) vs. AAA: median: 153.07 (interquartile range: 100.80-210.69) pg ml-1  mg tissue-1 , P < 0.05] and the expression levels of nitric oxide synthase 2 were significantly higher in AAA than in control. The protein expression level of NADPH oxidase subunits gp67-and gp91-phox, but did not gp47-phox, were also significantly higher in the AAA sites than in control. Addition of rivaroxaban to AAA sites explants significantly reduced the release of interleukin-6 [median: 51.61 (interquartile range: 30.87-74.03) pg ml-1  mg tissue-1 , P < 0.05 with respect to AAA alone] and the content of nitric oxide synthase 2, gp67 and gp91-phox NADPH subunits. The content of matrix metallopeptidase 9 was significantly higher in the AAA sites as compared to control. Rivaroxaban also reduced matrix metallopeptidase 9 content in AAA sites to similar levels to control. CONCLUSIONS: FXa inhibition by rivaroxaban exerted anti-inflammatory and antioxidative stress properties in human AAA sites, suggesting a role of FXa in these mechanisms associated with the pathogenesis of AAA.

Phase Transition, Dielectric Properties, and Ionic Transport in the [(CH3)2NH2]PbI3 Organic-Inorganic Hybrid with 2H-Hexagonal Perovskite Structure.

In this work, we focus on [(CH3)2NH2]PbI3, a member of the [AmineH]PbI3 series of hybrid organic-inorganic compounds, reporting a very easy mechanosynthesis route for its preparation at room temperature. We report that this [(CH3)2NH2]PbI3 compound with 2H-perovskite structure experiences a first-order transition at ≈250 K from hexagonal symmetry P63/mmc (HT phase) to monoclinic symmetry P21/c (LT phase), which involves two cooperative processes: an off-center shift of the Pb2+ cations and an order-disorder process of the N atoms of the DMA cations. Very interestingly, this compound shows a dielectric anomaly associated with the structural phase transition. Additionally, this compound displays very large values of the dielectric constant at room temperature because of the appearance of a certain conductivity and the activation of extrinsic contributions, as demonstrated by impedance spectroscopy. The large optical band gap displayed by this material (Eg = 2.59 eV) rules out the possibility that the observed conductivity can be electronic and points to ionic conductivity, as confirmed by density functional theory calculations that indicate that the lowest activation energy of 0.68 eV corresponds to the iodine anions, and suggests the most favorable diffusion paths for these anions. The obtained results thus indicate that [(CH3)2NH2]PbI3 is an electronic insulator and an ionic conductor, where the electronic conductivity is disfavored because of the low dimensionality of the [(CH3)2NH2]PbI3 structure.

Investigating the evolving microstructure of lithium metal electrodes in 3D using X-ray computed tomography.

The growth of electrodeposited lithium microstructures on metallic lithium electrodes has prevented their use in rechargeable lithium batteries due to early performance degradation and safety implications. Understanding the evolution of lithium microstructures during battery operation is crucial for the development of an effective and safe rechargeable lithium-metal battery. This study employs both synchrotron and laboratory X-ray computed tomography to investigate the morphological evolution of the surface of metallic lithium electrodes during a single cell discharge and over numerous cycles, respectively. The formation of surface pits and the growth of mossy lithium deposits through the separator layer are characterised in three-dimensions. This has provided insight into the microstructural evolution of lithium-metal electrodes during rechargeable battery operation, and further understanding of the importance of separator architecture in mitigating lithium dendrite growth.

Per- and polyfluoroalkyl substances in plasma and feathers of nestling birds of prey from northern Norway.

Plasma samples from nestlings of two top predators, White-tailed eagle (Haliaeetus albicilla) and Northern goshawk (Accipiter gentilis) from northern Norway were analysed for a wide range of per- and polyfluoroalkyl substances (PFASs). Body feathers from the White-tailed eagles were also analysed and significant associations between specific PFASs in blood plasma and body feathers were found (0.36

Effects of velocity loss during resistance training on athletic performance, strength gains and muscle adaptations.

We compared the effects of two resistance training (RT) programs only differing in the repetition velocity loss allowed in each set: 20% (VL20) vs 40% (VL40) on muscle structural and functional adaptations. Twenty-two young males were randomly assigned to a VL20 (n = 12) or VL40 (n = 10) group. Subjects followed an 8-week velocity-based RT program using the squat exercise while monitoring repetition velocity. Pre- and post-training assessments included: magnetic resonance imaging, vastus lateralis biopsies for muscle cross-sectional area (CSA) and fiber type analyses, one-repetition maximum strength and full load-velocity squat profile, countermovement jump (CMJ), and 20-m sprint running. VL20 resulted in similar squat strength gains than VL40 and greater improvements in CMJ (9.5% vs 3.5%, P < 0.05), despite VL20 performing 40% fewer repetitions. Although both groups increased mean fiber CSA and whole quadriceps muscle volume, VL40 training elicited a greater hypertrophy of vastus lateralis and intermedius than VL20. Training resulted in a reduction of myosin heavy chain IIX percentage in VL40, whereas it was preserved in VL20. In conclusion, the progressive accumulation of muscle fatigue as indicated by a more pronounced repetition velocity loss appears as an important variable in the configuration of the resistance exercise stimulus as it influences functional and structural neuromuscular adaptations.

Validation of the International Metastatic Renal-Cell Carcinoma Database Consortium (IMDC) prognostic model for first-line pazopanib in metastatic renal carcinoma: the Spanish Oncologic Genitourinary Group (SOGUG) SPAZO study.

BACKGROUND: Patients with metastatic renal carcinoma (mRCC) treated with first-line pazopanib were not included in the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) prognostic model. SPAZO (NCT02282579) was a nation-wide retrospective observational study designed to assess the effectiveness and validate the IMDC prognostic model in patients treated with first-line pazopanib in clinical practice. PATIENTS AND METHODS: Data of 278 patients, treated with first-line pazopanib for mRCC in 34 centres in Spain, were locally recorded and externally validated. Mean age was 66 years, there were 68.3% male, 93.5% clear-cell type, 74.8% nephrectomized, and 81.3% had ECOG 0-1. Metastatic sites were: lung 70.9%, lymph node 43.9%, bone 26.3%, soft tissue/skin 20.1%, liver 15.1%, CNS 7.2%, adrenal gland 6.5%, pleura/peritoneum 5.8%, pancreas 5%, and kidney 2.2%. After median follow-up of 23 months, 76.4% had discontinued pazopanib (57.2% due to progression), 47.9% had received second-line targeted therapy, and 48.9% had died. RESULTS: According to IMDC prognostic model, 19.4% had favourable risk (FR), 57.2% intermediate risk (IR), and 23.4% poor risk (PR). No unexpected toxicities were recorded. Response rate was 30.3% (FR: 44%, IR: 30% PR: 17.3%). Median progression-free survival (whole population) was 11 months (32 in FR, 11 in IR, 4 in PR). Median and 2-year overall survival (whole population) were 22 months and 48.1%, respectively (FR: not reached and 81.6%, IR: 22 and 48.7%, PR: 7 and 18.8%). These estimations and their 95% confidence intervals are fully consistent with the outcomes predicted by the IMDC prognostic model. CONCLUSION: Our results validate the IMDC model for first-line pazopanib in mRCC and confirm the effectiveness and safety of this treatment.

Liquid self-diffusion of H2O and DMF molecules in Co-MOF-74: molecular dynamics simulations and dielectric spectroscopy studies.

In this work we use molecular dynamics simulations to study the diffusion of N,N-dimethylformamide (DMF) and H2O as a function of temperature within the well-known metal-organic framework Co2(dobdc)·[G] (G = 2DMF·1H2O), also known as Co-MOF-74. The molecular dynamics simulations show that the diffusivity of guest molecules, which is almost negligible at low temperatures (T < 200 K), increases in the range of 200 < T (K) < 400 up to 3 and 4 orders of magnitude for DMF and H2O, respectively. This molecular diffusion can be easily detected by dielectric spectroscopy as it gives rise to extrinsic interfacial polarization effects that result in an apparent "colossal" dielectric constant at room temperature, εr' ∼ 42 000 (T = 300 K, ν = 10 Hz). Furthermore, the measured dielectric constant exhibits a thermal dependence similar to that of the diffusion coefficient, revealing the parallelism of the dielectric response and the molecular diffusion as a function of temperature. These results highlight: (a) the great utility of the fast and non-destructive dielectric and impedance spectroscopy techniques for the study and detection of the molecular transport of small polar molecules within porous metal-organic frameworks and related materials; (b) the peculiarity and uniqueness of MOF materials with "medium" size nanopores containing guest molecules as they are solid materials in which the guest molecules display a liquid state-like behaviour close to room temperature; and