Risks and benefits of sharing patient information on social media: a digital dilemma.

Social media (SoMe) has witnessed remarkable growth and emerged as a dominant method of communication worldwide. Platforms such as Facebook, X (formerly Twitter), LinkedIn, Instagram, TikTok, and YouTube have become important tools of the digital native generation. In the field of medicine, particularly, cardiology, attitudes towards SoMe have shifted, and professionals increasingly utilize it to share scientific findings, network with experts, and enhance teaching and learning. Notably, SoMe is being leveraged for teaching purposes, including the sharing of challenging and intriguing cases. However, sharing patient data, including photos or images, online carries significant implications and risks, potentially compromising individual privacy both online and offline. Privacy and data protection are fundamental rights within European Union treaties, and the General Data Protection Regulation (GDPR) serves as the cornerstone of data protection legislation. The GDPR outlines crucial requirements, such as obtaining 'consent' and implementing 'anonymization', that must be met before sharing sensitive and patient-identifiable information. Additionally, it is vital to consider the patient's perspective and prioritize ethical and social considerations when addressing challenges associated with sharing patient information on SoMe platforms. Given the absence of a peer-review process and clear guidelines, we present an initial approach, a code of conduct, and recommendations for the ethical use of SoMe. In conclusion, this comprehensive review underscores the importance of a balanced approach that ensures patient privacy and upholds ethical standards while harnessing the immense potential of SoMe to advance cardiology practice and facilitate knowledge dissemination.

Electronic and structural properties of Möbius boron-nitride and carbon nanobelts.

For the development of nanofilters and nanosensors, we wish to know the impact of size on their geometric, electronic, and thermal stabilities. Using the semiempirical tight binding method as implemented in the xTB program, we characterized Möbius boron-nitride and carbon-based nanobelts with different sizes and compared them to each other and to normal nanobelts. The calculated properties include the infrared spectra, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), the energy gap, the chemical potential, and the molecular hardness. The agreement between the peak positions from theoretical infrared spectra compared with experimental ones for all systems validates the methodology that we used. Our findings show that for the boron-nitride-based nanobelts, the calculated properties have an opposite monotonic relationship with the size of the systems, whereas for the carbon-based nanobelts, the properties show the same monotonic relationship for both types of nanobelts. Also, the torsion presented on the Möbius nanobelts, in the case of boron-nitride, induced an inhomogeneous surface distribution for the HOMO orbitals. High-temperature molecular dynamics also allowed us to contrast carbon-based systems with boron-nitride systems at various temperatures. In all cases, the properties vary with the increase in size of the nanobelts, indicating that it is possible to choose the desired values by changing the size and type of the systems. This work has many implications for future studies, for example our results show that carbon-based nanobelts did not break as we increased the temperature, whereas boron-nitride nanobelts had a rupture temperature that varied with their size; this is a meaningful result that can be tested when the use of more accurate simulation methods become practical for such systems in the future.

Möbius carbon nanobelts interacting with heavy metal nanoclusters.

CONTEXT: The interaction between carbon nanostructures and heavy metal clusters is of great interest due to their potential applications as sensors and filters to remove the former from environment. In this work, we investigated the interaction between two types of carbon nanobelts (Möbius-type nanobelt and simple nanobelt) and nickel, cadmium, and lead nanoclusters. Our aim was to determine how both systems interact which would shed light on the potential applications of the carbon nanostructures as pollutant removal and detecting devices. METHODS: To investigate the interaction between carbon nanostructures and heavy metal nanoclusters, we utilized the semiempirical tight binding framework provided by xTB software with the GFN2-xTB Hamiltonian. We performed calculations to determine the best interaction site, lowest energy geometries, complexes stability (using molecular dynamics at 298K), binding energy, and electronic properties. We also carried out a topological study to investigate the nature and intensity of the bonds formed between the metal nanoclusters and the nanobelts. Our results demonstrate that heavy metal nanoclusters have a favorable binding affinity towards both nanobelts, with the Möbius-type nanobelt having a stronger interaction. Additionally, our calculations reveal that the nickel nanocluster has the lowest binding energy, displaying the greatest charge transfer with the nanobelts, which was nearly twice that of the cadmium and lead nanoclusters. Our combined results lead to the conclusion that the nickel nanoclusters are chemisorbed, whereas cadmium and lead nanoclusters are physisorbed in both nanobelts. These findings have significant implications for the development of sensor and filtering devices based on carbon and heavy metal nanoclusters.

Micro-computed tomographic assessment of dentinal microcrack formation in straight and curved root canals in extracted teeth prepared with hand, rotary and reciprocating instruments.

AIM: To compare microcrack formation in roots of extracted teeth after the shaping of straight and curved root canals with hand, rotary and reciprocating files using micro-computed tomographic (micro-CT) analysis. METHODOLOGY: Thirty straight mandibular incisors and 30 severely curved mesial roots of mandibular molars were randomly divided into 6 experimental groups (n = 10) according to the systems used for the root canal preparation and the root canal curvature: ProTaper Universal for Hand Use (Dentsply Sirona, Ballaigues, Switzerland), HyFlex EDM (Coltene-Whaledent, Altstätten, Switzerland) and Reciproc Blue (VDW, Munich, Germany) files used in mandibular incisors (straight canals) and mesial roots of mandibular molars (curved canals). The roots were imaged with micro-CT scanning at an isotropic resolution of 14 µm before and after root canal preparation, and the cross-sectional images generated were assessed to detect microcracks. RESULTS: All dentinal defects identified after root canal preparation were already present before instrumentation, and no new microcracks were detected. Dentinal microcracks were present in 19% (ProTaper Universal for Hand Use), 11% (Hyflex EDM) and 23% (Reciproc Blue) of the cross-sections when the instrumentation was performed in mandibular incisors. Instrumentation of mandibular molars revealed microcracks in 15% (ProTaper Universal for Hand Use), 16% (Hyflex EDM) and 17% (Reciproc Blue) of the cross-sections. CONCLUSIONS: Preparation of straight and curved root canals with ProTaper Universal for Hand Use, HyFlex EDM and Reciproc Blue systems did not produce microcracks in extracted teeth when evaluated with micro-CT.

Efeito do ácido docosa-hexaenoico e do Trolox® no diluidor de refrigeração de sêmen de garanhões da raça Mangalarga Marchador / Effect of docosahexaenoic acid and Trolox® in extenders for cooling semen from Mangalarga Marchador stallion

Objetivou-se avaliar o efeito do ácido docosa-hexaenoico (DHA), associado ou não ao Trolox®, na refrigeração de sêmen de garanhões da raça Mangalarga Marchador. Foram refrigerados 10 ejaculados nos diluidores: D1) BotuSêmen® (BS; controle); D2) BS + 30ngmL-1 de DHA (BS30DHA); D3) BS30DHA + 40µM de Trolox® (BS30DHA40T); D4) BS + 50ngmL-1 de DHA (BS50DHA); D5) BS50DHA + 40µM de Trolox® (BS50DHA40T). Após 48 horas de refrigeração, foram avaliados os parâmetros de movimento espermático, a integridade estrutural e funcional da membrana plasmática e a longevidade espermática. Todos os diluidores testados preservaram, de forma semelhante, a motilidade, a linearidade, a retilinearidade, a amplitude do deslocamento lateral da cabeça, a frequência do batimento flagelar cruzado, o percentual de hiperativos e a integridade estrutural e funcional da membrana espermática (P>0,05). O diluidor BS50DHA foi superior ao BS30DHA40T em preservar a VCL e a VSL e foi superior ao BS30DHA40T e ao BS50DHA40T em preservar a VAP e o índice de oscilação (P<0,05). Conclui-se que o uso do Trolox® em diluidores utilizados para refrigeração de sêmen de garanhões contendo ácido docosa-hexaenoico, nas concentrações propostas, não é indicado por alterar parâmetros de movimento espermático considerados importantes para a fertilidade.(AU)

The objective of this study was to evaluate the effect of docosahexaenoic acid (DHA), associated or not with Trolox®, in extenders for cooling semen from Mangalarga Marchador stallions. Ten ejaculates were cooled in the following diluents: D1) BotuSemen® (BS; control); D2) BS + 30ngmL-1 DHA (BS30DHA); D3) BS30DHA + 40µM Trolox® (BS30DHA40T); D4) BS + 50ngmL-1 DHA (BS50DHA); D5) BS50DHA + 40µM Trolox® (BS50DHA40T). After 48 hours of refrigeration, the sperm movement, structural and functional integrity of the plasma membrane and sperm longevity were evaluated. All extenders tested similarly preserved motility, linearity, straightness of trajectory, amplitude of lateral head displacement, beat cross frequency, hyperactive, the structural and functional integrity of the sperm membrane (P> 0.05). The BS50DHA extender was superior to BS30DHA40T in preserving VCL and VSL and was superior to BS30DHA40T and BS50DHA40T in preserving VAP and oscillation index (P< 0.05). It is concluded that the use of Trolox® in extenders for cooling stallion sperm containing docosahexaenoic acid at the proposed concentrations is not indicated because it alters sperm movement parameters considered important for fertility.(AU)

ARNIs: balancing "the good and the bad" of neuroendocrine response to HF.

BACKGROUND: A new class of drugs-angiotensin receptor, neprylisin inhibitors, ARNI-has shown to be prognostic superior in HFrEF to the sole inhibition of the renin-angiotensin axes with enalapril. The ultimate mechanism of action of ARNIs is unknown. AIM: We have considered that ARNI exerts a positive modulation of the neuroendocrine balance, with enhancement of the physiological diuresis and dilatation due to neprylisin inhibition by sacubitril. This represents a shift in HF medical therapy always directed to counteract (with inhibitors of the renin-angiotensin system, beta blockers or inhibitors of aldosterone) the so-called "bad" neuroendocrine response. Development of ARNI, on the contrary, has led to consider the neuroendocrine response to HFrEF from a different angle, which is to say that the activation is not always deleterious, but it could also be beneficial. This concept is highlighted by the enhancement of the activity of atrial natriuretic peptide, induced by sacubitril/valsartan in the PARADIGM trial, and found as proof from early studies on untreated patients with constrictive pericarditis. The possibility that sacubitril inhibition of neprylisin acts by enhancing substance P and gene-related calcitonin peptide is also considered, as well as the negative effect of neprylisin inhibition. CONCLUSIONS: The beneficial effects of ARNI are related, in part at least, to a positive modulation of the neuroendocrine response to the disease, resulting in an increase of physiological diuresis and dilatation.

Difteria: Experiencia en el servicio de enfermedades infecciosas del Hospital Universitario de Caracas

Difteria es una enfermedad infecciosa bacteriana producida por Corynebacterium diphtheriae, es altamente contagiosa, prevenible por vacunas, con importantes complicaciones agudas y alta mortalidad. Objetivo: Describir las características clínicoepidemiológicas y el manejo médico de los pacientes con diagnóstico de Difteria ingresados en el Servicio de Enfermedades Infecciosas del Adulto del Hospital Universitario de Caracas (HUC) en los años 2017 y 2018. Metodología: Estudio de casos, analítico, retrospectivo, de revisión de historias clínicas. Resultados: Ingresaron 27 pacientes de los cuales se encontraron 22 historias clínicas y se excluyeron 2. De los 20 pacientes 13 (65 %) ingresaron en el año 2017 y 7 (35 %) hasta mayo del 2018. Predominó el género masculino 11 (55 %). La mayoría eran procedentes del Distrito Capital 9 (45 %), seguido del estado Miranda 8 (40 %). El promedio de edad fue de 26 años. La mayoría 8 (40 %) no tenían reportes de datos epidemiológicos en la historia clínica, 7 (35 %) negaron viajes recientes, 3 (15 %) estaban vacunados. La mayoría de los pacientes consultaron por fiebre, odinia y odinofagia 13 (65 %), seguido de fiebre y odinia 6 (30 %), el 100 % tuvo membrana blanco grisácea como clínica primaria, seguido de edema de cuello 10 (50 %). La ubicación de las membranas fue más frecuente en amígdalas palatinas 15 (75 %), con 9 casos (45 %) de formas extensivas a úvula, paladar blando y paredes de orofaringe. Las complicaciones al ingreso fueron respiratorias 9 (45 %) y neurológicas 1 (5 %). El tratamiento fue penicilina cristalina en 12 casos (60 %) y antitoxina diftérica (ATD) en el 100 %, la mayoría administrada en las primeras 24 hrs 9 (45 %). Un paciente presentó polineuropatía y 1 falleció por insuficiencia respiratoria. Conclusiones: El HUC es un centro de referencia y es pertinente determinar las características clínico-epidemiológicas y el manejo médico de los pacientes hospitalizados con diagnóstico de difteria, en el contexto de la actual epidemia.

Diphtheria is a bacterial infectious disease caused by Corynebacterium diphtheriae, it is highly contagious, preventable by vaccines, with important acute complications and high mortality. Objective: To describe the clinical-epidemiological characteristics and medical management of patients diagnosed with Diphtheria admitted to the Adult Infectious Diseases Service of the Hospital Universitario de Caracas (HUC) in the years 2017 and 2018. Methodology: Case study, analytical , retrospective, review of medical records. Results: 27 patients were admitted, of which 22 clinical records were found and 2 were excluded. Of the 20 patients, 13 (65%) entered in 2017 and 7 (35%) up to May 2018. The male gender predominated 11 (55 %). Most were from Distrito Capital 9 (45%), followed by Miranda 8 (40%). The average age was 26 years. The majority 8 (40%) had no reports of epidemiological data in the clinical history, 7 (35%) denied recent trips, 3 (15%) were vaccinated. The majority of patients consulted for fever, odinia and odynophagia 13 (65%), followed by fever and odinia 6 (30%), 100% had grayish white membrane as primary clinic, followed by neck edema 10 (50%) . The location of the membranes was more frequent in palatine tonsils 15 (75%), with 9 cases (45%) of extensive forms to the uvula, soft palate and walls of the oropharynx. Complications at admission were respiratory 9 (45%) and neurological 1 (5%). The treatment was crystalline penicillin in 12 cases (60%) and diphtheria antitoxin (DAT) in 100%, the majority administered in the first 24 h 9 (45%). One patient presented polyneuropathy and 1 died due to respiratory failure. Conclusions: The HUC is a reference center and it is pertinent to determine the clinical-epidemiological characteristics and medical management of hospitalized patients diagnosed with diphtheria, in the context of the current epidemic.

Rituximab use in pediatric lupus anticoagulant hypoprothrombinemia syndrome - report of three cases and review of the literature.

Lupus anticoagulant hypoprothrombinemia syndrome (LA-HPS) is a rare condition that may predispose both to thrombosis and bleeding due to positive lupus anticoagulant (LA) and factor II (FII) deficiency. It can be seen in association with infections or systemic lupus erythematosus (SLE) and may require glucocorticoids (GCs) and/or immunosuppressive medications. Pediatric LA-HPS cases in the literature and three cases that received only rituximab (RTX) for LA-HPS (in addition to GCs) at two institutions between January 2010 and June 2017 were analyzed descriptively. Pediatric LA-HPS cases (≤18 years) with bleeding or thrombotic events were included. Information obtained included demographics, presenting symptoms, diagnoses, treatments, pre-/post-treatment prothrombin time (PT)/partial thromboplastin time (PTT)/LA/FII levels, and outcomes. In addition to three LA-HPS cases identified at our institutions, as of June 2017, 37 articles reported 54 pediatric LA-HPS cases (mean age: 8 years (0.9-17 years); female/male: (2:1); viral illness 27 (50%), SLE 20 (37%), and other six (11%)). All cases had a positive LA and FII deficiency (range: 0%-40%). All cases presented with bleeding diathesis and were treated with various regimens, but there was no reported use of RTX. The purpose of this report is to describe the novel use of RTX as a steroid-sparing agent in three pediatric SLE cases and to systematically review the literature on pediatric cases of LA-HPS.

The histamine H3 receptor antagonist thioperamide rescues circadian rhythm and memory function in experimental parkinsonism.

Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by motor impairment and a wide range of non-motor symptoms, including sleep disorders and cognitive and affective deficits. In this study, we used a mouse model of PD based on 6-hydroxydopamine (6-OHDA) to examine the effect of thioperamide, a histamine H3 receptor antagonist, on circadian activity, recognition memory and anxiety. A partial, bilateral 6-OHDA lesion of the striatum reduces motor activity during the active phase of the 24 h cycle. In addition, the lesion disrupts the endogenous circadian rhythm observed when mice are maintained in constant darkness. Administration of thioperamide to 6-OHDA-lesion mice rescues the normal rest/activity cycle. Moreover, thioperamide counteracts the deficit of novel object recognition produced by 6-OHDA. Our experiments show that this memory impairment is accompanied by disrupted gamma oscillations in the hippocampus, which are also rescued by thioperamide. In contrast, we do not observe any modification of the anxiogenic effect of 6-OHDA in response to administration of thioperamide. Our results indicate that thioperamide may act as a multifunctional drug, able to counteract disruptions of circadian rhythm and cognitive deficits associated with PD.

Chronic nicotine attenuates behavioral and synaptic plasticity impairments in a streptozotocin model of Alzheimer's disease.

Brain glucose metabolism is altered in sporadic Alzheimer's disease (sAD), whose pathologies are reproduced in rodents by intracerebroventricular (icv) infusion of streptozotocin (STZ) in subdiabetogenic doses. The icv-STZ model also culminates in central cholinergic dysfunctions, which in turn are known to underlie both the sAD cognitive decline, and synaptic plasticity impairments. Considering the cognitive-enhancing potential of chronic nicotine (Nic), we investigated whether it attenuates icv-STZ-induced impairments in recognition memory and synaptic plasticity in a cognition-relevant substrate: the hippocampal CA1-medial prefrontal cortex (mPFC) pathway. Rats treated with icv-STZ were submitted to a chronic Nic regime, and were evaluated for recognition memory. We then examined long-term potentiation (LTP), paired-pulse facilitation (PPF) under urethane anesthesia, and brains were also evaluated for hippocampus-mPFC cell density. We found that Nic treatment prevents icv-STZ-induced disruptions in recognition memory and LTP. STZ did not precipitate neuronal death, while Nic alone was associated with higher neuronal density in CA1 when compared to vehicle-injected animals. Through combining behavioral, neurophysiological, and neuropathological observations into the Nic-STZ interplay, our study reinforces that cholinergic treatments are of clinical importance against early-stage Alzheimer's disease and mild cognitive impairments.

Effector memory CD4(+) T cells differentially express activation associated molecules depending on the duration of American cutaneous leishmaniasis lesions.

A high number of Leishmania-responder T cells is found in cutaneous leishmaniasis lesions, suggesting that important immunological events occur at the site of infection. Although activated, cytotoxic and regulatory T cells infiltrating into lesions may influence disease pathogenesis, the role of the T cell differentiation pattern of lymphocytes in lesions is unknown. Our aim was to investigate whether the phase of lesion development (early or late) is influenced by the functional status of cells present in inflammatory infiltrate. Activation, cytotoxity and T cell differentiation molecules were evaluated in lesion mononuclear cells by flow cytometry. The frequency of T cells was correlated with the lesion area (r = 0·68; P = 0·020). CD4(+) CD25(+) T cells predominated over CD4(+) CD69(+) T cells in early lesions (less than 30 days), whereas late lesions (more than 60 days) exhibited more CD4(+) CD69(+) T cells than CD4(+) CD25(+) T cells. The duration of illness was correlated positively with CD4(+) CD69(+) (r = 0·68; P = 0·005) and negatively with CD4(+) CD25(+) T cells (r = -0·45; P = 0·046). Most CD8(+) T cells expressed cytotoxic-associated molecules (CD244(+) ), and the percentages were correlated with the lesion area (r = 0·52; P = 0·04). Both CD4(+) and CD8(+) effector memory T cells (TEM -CD45RO(+) CCR7(-) ) predominated in CL lesions and were significantly higher than central memory (TCM -CD45RO(+) CCR7(+) ) or naive T cells (CD45RO(-) CCR7(+) ). An enrichment of TEM cells and contraction of naive T cells were observed in lesions in comparison to blood (P = 0·006) for both CD4(+) and CD8(+) T cells. Lesion chronicity is associated with a shift in activation phenotype. The enrichment of TEM and activated cytotoxic cells can contribute to immune-mediated tissue damage.

The role of tenofovir alafenamide in future HIV management.

HIV infection has become a chronic condition rather than an acute life-threatening disease in developed countries, thanks to consistent innovation and evolution of effective interventions. This has altered HIV management and created new challenges. People living with HIV (PLWHIV) are living longer and so encounter comorbidities linked not only with their disease, but also with ageing, lifestyle and chronic exposure to antiretroviral therapy (ART). Although longevity, viral suppression and the prevention of viral transmission remain key goals, more needs to be achieved to encompass the vision of attaining an optimum level of overall health. Treatment choices and management practices should ensure patients' long-term health with minimal comorbidity. Treatments that balance optimal efficacy with the potential for improved long-term safety are needed for all patients. In this review, we consider the evolution and development of tenofovir alafenamide (TAF), a novel prodrug of tenofovir which offers high antiviral efficacy at doses over ten times lower than that of tenofovir disoproxil fumarate (TDF). Emerging clinical data suggest that elvitegravir, cobicistat, emtricitabine and TAF (E/C/F/TAF) as a single-tablet regimen offers highly effective viral suppression in treatment-naïve and treatment-experienced patients with an improved renal and bone safety profile compared with TDF, this having been demonstrated in diverse groups including patients with existing renal impairment and adolescents. The profile of TAF identifies it as an agent with a promising role within future ART regimens that aim to deliver the vision of undetectable viral load, while requiring less monitoring and having a safety profile designed to minimize comorbid risks while supporting good long-term health.

Renal and cardiovascular risk predictive value of two different microalbuminuria screening methods in patients with hypertension with/without diabetes in Portugal.

MicRoAlbuminuria sCreening survEy (RACE) was a multicentre, observational, cross-sectional study conducted in primary health-care settings of Portugal. Here, we present a post-hoc analysis from the RACE study, assessing the renal and cardiovascular (CV) risk predictive value of two different microalbuminuria (MA) screening methods, nephelometry with 24-h urine (MA-24 h) and Micral test with occasional urine (MicralA) in patients with hypertension (HTN) with/without type 2 diabetes mellitus (T2DM). Out of 3065 patients, 1173 (38.3%) were in the HTN group without T2DM (HTN) and 1892 (61.7%) in the HTN group with T2DM (HTN+T2DM). The overall prevalence of MA was 50.6% determined by MicralA and 22.1% with MA-24 h. Urinary albumin excretion data obtained by both techniques correlated significantly (rs=0.586; P<0.001). In all subjects, MicralA showed a sensitivity of 93%, specificity of 62% for detection of MA, with a positive predictive value of 41% and negative predictive value of 97%. With both methods, the presence of MA was independently associated with a higher risk (1.5- to 2.9-fold) of CV and renal organ damage in both HTN and HTN+T2DM groups. MicralA, due to its high sensitivity and negative predictive value, can be considered as a valid and reliable method for MA screening in patients with HTN with/without T2DM.

Differentiation of equine induced pluripotent stem cells into a keratinocyte lineage.

REASONS FOR PERFORMING STUDY: Skin trauma in horses often leads to the development of chronic nonhealing wounds that lack a keratinocyte cover, vital for healing. Reports in mouse and man confirm the possibility of generating functional keratinocytes from induced pluripotent stem cells (iPSC), thus presenting myriad potential applications for wound management or treatment of skin disease. Similarly, differentiation of equine iPSC (eiPSC) into a keratinocyte lineage should provide opportunities for the advancement of veterinary regenerative medicine. OBJECTIVES: The purpose of this study was to develop an efficient method for the differentiation of eiPSC into a keratinocyte lineage. It was hypothesised that eiPSC can form differentiated keratinocytes (eiPSC-KC) comparable with primary equine keratinocytes (PEK) in their morphological and functional characteristics. STUDY DESIGN: Experimental in vitro study. METHODS: Equine iPSC established using a nonviral system were treated for 30 days with retinoic acid and bone morphogenetic protein-4 to induce directed differentiation into iPSC-KC. Temporospatial gene and protein expression by eiPSC-KC was measured at weekly intervals of differentiation and in response to calcium switch. Proliferative and migratory capacities of eiPSC-KC were compared with those of PEK. RESULTS: Equine iPSC, upon directed differentiation, showed loss of pluripotency genes and progressive increase in pancytokeratin expression indicating ectodermal specification into keratinocytes. High differentiation efficiency was achieved, with 82.5% of eiPSC expressing keratin 14, a marker of epidermal-specific basal stem cells, after 30 days of directed differentiation. Moreover, the proliferative capacity of eiPSC-KC was superior, while the migratory capacity (measured as the ability to epithelise in vitro wounds) was comparable with that of PEK. CONCLUSIONS: This proof of concept study suggests that eiPSC can successfully be differentiated into equine keratinocytes (eiPSC-KC) with features that are promising to the development of a stem cell-based skin construct, with the potential to regenerate lost or damaged skin.

The frequency of spontaneous seizures in rats correlates with alterations in sensorimotor gating, spatial working memory, and parvalbumin expression throughout limbic regions.

Cognitive deficits and psychotic symptoms are highly prevalent in patients with temporal lobe epilepsy (TLE). Imaging studies in humans have suggested that these comorbidities are associated with atrophy in temporal lobe structures and other limbic regions. It remains to be clarified whether TLE comorbidities are due to the frequency of spontaneous seizures or to limbic structural damage per se. Here, we used the pilocarpine model of chronic spontaneous seizures to evaluate the possible association of seizure frequency with sensorimotor gating, spatial working memory, and neuropathology throughout limbic regions. For TLE modeling, we induced a 2-h status epilepticus by the systemic administration of lithium-pilocarpine. Once spontaneous seizures were established, we tested the locomotor activity (open field), spatial working memory (eight-arm radial maze), and sensorimotor gating (prepulse inhibition of acoustic startle). After behavioral testing, the brains were sectioned for hematoxylin-eosin staining (cell density) and parvalbumin immunohistochemistry (GABAergic neuropil) in the prefrontal cortex, nucleus accumbens, thalamus, amygdala, hippocampus, and entorhinal cortex. The animal groups analyzed included chronic epileptic rats, their controls, and rats that received lithium-pilocarpine but eventually failed to express status epilepticus or spontaneous seizures. Epileptic rats showed deficits in sensorimotor gating that negatively correlated with the radial maze performance, and impairments in both behavioral tests correlated with seizure frequency. In addition to neuronal loss at several sites, we found increased parvalbumin immunostaining in the prefrontal cortex (infralimbic area), thalamus (midline and reticular nuclei), amygdala, Ammon's horn, dentate gyrus, and entorhinal cortex. These tissue changes correlated with seizure frequency and impairments in sensorimotor gating. Our work indicates that chronic seizures might impact the inhibitory-excitatory balance in the temporal lobe and its interconnected limbic regions, which could increase the likelihood of cognitive deficits and interictal psychiatric disorders.

Immune potential of allogeneic equine induced pluripotent stem cells.

REASONS FOR PERFORMING STUDY: Induced pluripotent stem cells (iPSC) have brought immense hope to cellular therapy and regenerative medicine. However, the antigenicity of iPSC has not been well documented and remains a hurdle for clinical applications. Expression of major histocompatibility complex (MHC) molecules by human and murine iPSC is downregulated, making these cells potentially safe for transplantation. No such data are available for any large animal model. OBJECTIVES: To measure expression of MHC molecules on equine iPSC (eiPSC) and describe their antigenicity using intradermal testing. The hypothesis was that allogeneic eiPSC weakly express MHC molecules and would not elicit a rejection response when injected intradermally. STUDY DESIGN: Experimental study involving both in vitro and in vivo components. METHODS: Two green fluorescent protein-expressing eiPSC lines were analysed by flow cytometry for MHC expression. One line was then transplanted intradermally, along with appropriate controls, into 2 unrelated experimental horses. Blood was collected pre- and 7 days post transplantation. The wheals formed at the sites of injection were measured at regular intervals beginning at 0.25 h until 4 weeks. Tissue samples of the injected sites were obtained at 2, 3, 7 and 30 days post transplantation and analysed by histopathology and immunofluorescence. RESULTS: Both eiPSC lines weakly expressed MHC molecules. eiPSC were detectable up to 7 days following allogeneic transplantation and elicited no apparent systemic response. Injection of eiPSC caused small wheal formation at the skin surface. Skin sections revealed CD4(+) and CD8(+) mononuclear cells up to 30 days post transplantation. CONCLUSIONS: These data suggest that while transplantation of allogeneic eiPSC elicits a moderate cellular response, it does not cause acute rejection. The feasibility of banking allogeneic iPSC for regenerative medicine applications should be explored.