Multisystemic inflammatory syndrome related to COVID-19, with latent tuberculosis in bone marrow, and satisfactory response to tocilizumab, in a 7-year-old boy.

Paediatric inflammatory multisystem syndrome temporally associated with COVID-19 (PIMS-TS) or multisystem inflammatory syndrome in children (MIS-C) is a new acute-onset systemic inflammatory disease, which mainly affects children. Latent tuberculosis infection (LTBI) is characterized by the presence of immune sensitization to Mycobacterium tuberculosis (MTB) in the absence of any clinical or radiological evidence of active disease. We present a child with MIS-C related to COVID-19, with latent TB in the bone marrow, and satisfactory response to tocilizumab. It is important to pay attention in the investigation of TB cases in countries with a high prevalence of tuberculosis, especially when opting for immunusuppression.

New diketopiperazines as vectors for peptide protection and brain delivery: Synthesis and biological evaluation.

New strategies allowing the transfer of molecules, especially peptides, through the blood-brain barriers are a major pharmacological challenge for the treatment of brain diseases. The present study aims at evaluating in vivo the cerebral bioavailability of carrier systems, based on small and functionalizable 2,5-diketopiperazine (DKP) motifs. We studied 2 different cyclo(Lys-Lys) DKP scaffolds alone and a cyclo(Lys-Gly) DKP carrier bearing as peptide model, the tau protein hexapeptide VQIVYK sequence. The different carrier systems were synthesized and radiolabeled using one of the free domains. The stability, biodistribution, and ability to cross blood-brain barrier were investigated in vivo in mice for 99m Tc-DKP scaffolds, 99m Tc-HVQIVYK peptide alone, and 99m Tc-DKP-VQIVYK. 125 I-labelled bovine serum albumin was used as negative control for brain uptake. Both radiolabeled DKPs scaffolds and 99m Tc-DKP-VQIVYK showed a high stability, while peptide 99m Tc-HVQIVYK alone was quickly degraded in vivo. The presence of 99m Tc-DKPs scaffolds and 99m Tc-DKP-VQIVYK was observed in the ventricular and subarachnoid spaces and to a lower extent in the brain parenchyma up to 45 minutes post-injection in mice. This work highlights the potentiality of DKP scaffolds as vectors to transport peptides into the brain by limiting proteolysis and favoring cerebral bioavailability.

A physiologically relevant culture platform for long-term studies of in vitro gingival tissue.

There is a clinical need to understand the etiologies of periodontitis, considering the growing socio-economic impact of the disease. Despite recent advances in oral tissue engineering, experimental approaches have failed to develop a physiologically relevant gingival model that combines tissue organization with salivary flow dynamics and stimulation of the shedding and non-shedding oral surfaces. Herein, we develop a dynamic gingival tissue model composed of a silk scaffold, replicating the cyto-architecture and oxygen profile of the human gingiva, along with a saliva-mimicking medium that reflected the ionic composition, viscosity, and non-Newtonian behavior of human saliva. The construct was cultured in a custom designed bioreactor, in which force profiles on the gingival epithelium were modulated through analysis of inlet position, velocity and vorticity to replicate the physiological shear stress of salivary flow. The gingival bioreactor supported the long-term in vivo features of the gingiva and improved the integrity of the epithelial barrier, critical against the invasion of pathogenic bacteria. Furthermore, the challenge of the gingival tissue with P. gingivalis lipopolysaccharide, as an in vitro surrogate for microbial interactions, indicated a greater stability of the dynamic model in maintaining tissue homeostasis and, thus, its applicability in long-term studies. The model will be integrated into future studies with the human subgingival microbiome to investigate host-pathogen and host-commensal interactions. STATEMENT OF SIGNIFICANCE: The major societal impact of human microbiome had reverberated up to the establishment of the Common Fund's Human Microbiome Project, that has the intent of studying the role of microbial communities in human health and diseases, including periodontitis, atopic dermatitis, or asthma and inflammatory bowel disease. In addition, these chronic diseases are emergent drivers of global socioeconomic status. Not only common oral diseases have been shown to be directly correlated with several systemic conditions, but they are differentially impacting some racial/ethnic and socioeconomic groups. To address this growing social disparity, the development of in vitro gingival model would provide a time and cost-effective experimental platform, able to mimic the spectrum of periodontal disease presentation, for the identification of predictive biomarkers for early-stage diagnosis.

Pre-clinical and clinical evaluation of nuclear tracers for the molecular imaging of vulnerable atherosclerosis: an overview.

Cardiovascular diseases (CVD) are the leading cause of mortality worldwide. Despite major advances in the treatment of CVD, a high proportion of CVD victims die suddenly while being apparently healthy, the great majority of these accidents being due to the rupture or erosion of a vulnerable coronary atherosclerotic plaque. A non-invasive imaging methodology allowing the early detection of vulnerable atherosclerotic plaques in selected individuals prior to the occurrence of any symptom would therefore be of great public health benefit. Nuclear imaging could allow the identification of vulnerable patients by non-invasive in vivo scintigraphic imaging following administration of a radiolabeled tracer. The purpose of this review is to provide an overview of radiotracers that have been recently evaluated for the detection of vulnerable plaques together with the biological rationale that initiated their development. Radiotracers targeted at the inflammatory process seem particularly relevant and promising. Recently, macrophage targeting allowed the experimental in vivo detection of atherosclerosis using either SPECT or PET. A few tracers have also been evaluated clinically. Targeting of apoptosis and macrophage metabolism both allowed the imaging of vulnerable plaques in carotid vessels of patients. However, nuclear imaging of vulnerable plaques at the level of coronary arteries remains challenging, mostly because of their small size and their vicinity with unbound circulating tracer. The experimental and pilot clinical studies reviewed in the present paper represent a fundamental step prior to the evaluation of the efficacy of any selected tracer for the early, non-invasive detection of vulnerable patients.

Mapping of brain tissue hematocrit in glioma and acute stroke using a dual autoradiography approach.

Hematocrit (Hct) determines the ability of blood to carry oxygen. While changes in systemic Hct are known to impact stroke or tumor control, changes in local (tissue) Hct (tHct) induced by these diseases have however received little attention. In this study, we evaluate tHct in acute stroke and in glioma models using a new approach to map tHct across the brain, a dual isotope autoradiography, based on injections of 125I-labeled albumin and 99mTc-lalbeled red blood cells in the same animal. For validation purpose, tHct was mapped in the rat brain (i) under physiological conditions, (ii) following erythropoietin injection, and (iii) following hemodilution. Then, tHct was then mapped in stroke (middle cerebral artery occlusion) and tumor models (9LGS and C6). The mean tHct values observed in healthy brains (tHct = 29 ± 1.3%), were modified as expected by erythropoietin (tHct = 36.7 ± 2.6%) and hemodilution (tHct = 24.2 ± 2.4%). Using the proposed method, we observed a local reduction, spatially heterogeneous, in tHct following acute stroke (tHct = 19.5 ± 2.5%) and in both glioma models (9LGS: tHct = 18.5 ± 2.3%, C6: tHct = 16.1 ± 1.2%). This reduction and this heterogeneity in tHct observed in stroke and glioma raises methodological issues in perfusion imaging techniques where tHct is generally overlooked and could impact therapeutic strategies.

Biodistribution and preliminary toxicity studies of nanoparticles made of Biotransesterified ß-cyclodextrins and PEGylated phospholipids.

BACKGROUND: The modification of ß-cyclodextrins (ßCDs) by grafting alkyl chains on the primary and/or secondary face yields derivatives (ßCD-C10) able to self-organize under nanoprecipitating conditions into nanoparticles (ßCD-C10-NP) potentially useful for drug delivery. The co-nanoprecipitation of ßCD-C10 with polyethylene glycol (PEG) chains yields PEGylated NPs (ßCD-C10-PEG-NP) with potentially improved stealthiness. The objectives of the present study were to characterize the in vivo biodistribution of ßCD-C10-PEG-NP with PEG chain length of 2000 and 5000Da using nuclear imaging, and to preliminarily evaluate the in vivo acute and extended acute toxicity of the most suitable system. RESEARCH DESIGN AND METHODS: The in vivo and ex vivo biodistribution features of naked and decorated nanoparticles were investigated over time following intravenous injection of 125I-radiolabeled nanoparticles to mice. The potential toxicity of PEGylated ßCD-C10 nanosuspensions was evaluated in a preliminary in vivo toxicity study involving blood assays and tissue histology following repeated intraperitoneal injections of nanoparticles to healthy mice. RESULTS: The results indicated that ßCD-C10-PEG5000-NP presented increased stealthiness with decreased in vivo elimination and increased blood kinetics without inducing blood, kidney, spleen, and liver acute and extended acute toxicity. CONCLUSIONS: ßCD-C10-PEG5000-NPs are stealth and safe systems with potential for drug delivery.

Lercanidipine, enalapril and their combination in the treatment of elderly hypertensive patients: placebo-controlled, randomized, crossover study with four ABPM.

This double-blind, placebo-controlled, four-way balanced design crossover study included hypertensive patients aged 60-85 years with mean office-measured sitting systolic blood pressure (SBP) 160-179 mm Hg and daytime SBP > or =135 mm Hg. After a 2-week run-in period, during which previous medications were discontinued, each patient received the following four treatments in randomized order for 4 weeks each: lercanidipine 10 mg (L), enalapril 20 mg (E), lercanidipine 10 mg plus enalapril 20 mg (L/E) and placebo (P). At the end of each treatment period, office trough blood pressure (BP) was measured and a 24-h Ambulatory Blood Pressure Monitoring (ABPM) was performed. Seventy-five patients (mean age 66 years, office BP 168/92 mm Hg, daytime SBP 151 mm Hg) were randomized and 62 completed the study with four valid post-baseline ABPMs. The administration of P, L, E and L/E was associated with a mean 24-h SBP of 144, 137, 133 and 127 mm Hg, respectively. All active treatments significantly reduced the mean 24-h SBP in comparison with placebo, but L/E was significantly more effective than L and E alone. Similarly, office SBP was significantly more reduced with L/E (-16.9 mm Hg) than with L (-5.0 mm Hg) or E (-5.9 mm Hg). A BP <140/90 mm Hg was recorded in 18% of patients with L, 19% with E and 45% with L/E. Two patients on P and two on L/E were withdrawn from the study due to adverse events. In conclusion, combination therapy with L/E has additive antihypertensive effects on both ambulatory and office BP in elderly patients and is well tolerated.

Morphometric study of the interproximal unit in the esthetic region to correlate anatomic variables affecting the aspect of soft tissue embrasure space.

BACKGROUND: The presence of a normal papilla is crucial to avoid the unpleasant esthetic defects that are of major concern to periodontists, restorative dentists, and patients. During the course of progressive periodontitis and following periodontal treatment, it is not uncommon to have a partial loss of the interdental papilla. This loss can lead to an unesthetic gingival appearance. This study evaluated different anatomic variables in an effort to determine their role in the papillary appearance of maxillary incisors. METHODS: A total of 178 interdental embrasures in 58 patients were selected randomly for examination. For each patient, a digital photograph and a modified periapical radiograph of the interdental embrasure of the four maxillary incisors were taken by using a special metric device fixed to a centrator as a reference marker. Clinical and radiographic data were obtained for the distance from the contact point to the alveolar crest and for the interradicular distance. We used a classification system with regard to peri-implant soft tissue based on esthetic assessments related to the space between reference lines through the highest gingival curvature of the crown-tooth margin and the contact point. RESULTS: In the group of interdental sites with an interradicular distance of less than approximately 2.4 mm, an increase in the distance between the contact point and the bone crest corresponded to a marked increase in the interdental black triangle's dimensions and, therefore, a less esthetic smile. In particular, when the interradicular distance was >2.4 mm, we statistically estimated that the other anatomic variable considered, the distance from the contact point to the alveolar crest, lost its influence on whether the interdental papilla would be present or absent. CONCLUSION: The interradicular distance and the distance between the contact point and the alveolar crest have independent and combined effects on the presence or absence of the interdental papilla.

JAGGED2: a putative Notch ligand expressed in the apical ectodermal ridge and in sites of epithelial-mesenchymal interactions.

The Drosophila Notch gene and its ligands, Delta and Serrate, are involved in cell fate determination in a variety of developing tissues. Recently, several Notch, Delta and Serrate homologues have been identified in vertebrates. We report here the cloning of the human and murine JAGGED2 (JAG2), a Serrate-like gene, and the analysis of its expression pattern during embryogenesis. Jag2 was found to be expressed as early as E9 in the surface ectoderm of the branchial arches and in the apical ectodermal ridge (AER) of the developing limb. At E12.5, Jag2 expression is upregulated in differentiated neurons of the central and peripheral nervous system and in the inner neuroblastic layer of the developing retina. Outside the nervous system, Jag2 is expressed in the developing vibrissae follicles, tooth buds, thymus, submandibular gland and stomach. Our findings suggest the involvement of Jagged2 in the development of the mammalian limb, branchial arches, central and peripheral nervous systems and several tissues whose development depends upon epithelial-mesenchymal interactions.

Response of colonic motility to dopaminergic stimulation is subverted in rats with nigrostriatal lesion: relevance to gastrointestinal dysfunctions in Parkinson's disease.

BACKGROUND: Constipation is extremely common in patients with Parkinson's disease (PD) and has been described in PD animal models. In this study, we investigated whether a PD-like degeneration of dopaminergic neurons of the substantia nigra can influence peristalsis in colonic segments of rats by impacting on enteric dopaminergic transmission. METHODS: Male, Sprague-Dawley rats received a unilateral injection of neurotoxin 6-hydroxydopamine (6-OHDA), or saline, into the medial-forebrain-bundle. Peristaltic activity was recorded in isolated colonic segments, in baseline conditions and following exposure to combinations of D2 receptor (DRD2) agonist sumanirole and antagonist L-741626. Dopamine levels and DRD2 expression were assessed in the ileum and colon of animals. We also investigated the involvement of the dorsal motor nucleus of the vagus (DMV) - a potential relay station between central dopaminergic denervation and gastrointestinal (GI) dysfunction - by analyzing cytochrome c oxidase activity and FosB/DeltaFosB expression in DMV neurons. KEY RESULTS: We observed profound alterations in the response of colonic segments of 6-OHDA lesioned animals to DRD2 stimulation. In fact, the inhibition of colonic peristalsis elicited by sumanirole in control rats was absent in 6-OHDA-lesioned animals. These animals also showed reduced DRD2 expression in the colon, along with elevation of dopamine levels. No significant changes were detected within the DMV. CONCLUSIONS & INFERENCES: Our results demonstrate that selective lesion of the nigrostriatal dopaminergic pathway subverts the physiological response of the colon to dopaminergic stimulation, opening new perspectives in the comprehension and treatment of GI dysfunctions associated with PD.

Ras p21 protein promotes survival and differentiation of human embryonic neural crest-derived cells.

We have previously shown that the oncogene product p21 Ras is essential for the survival and neurite outgrowth-promoting activity of nerve growth factor on cultured chick embryonic sensory, but not sympathetic neurons. In order to extend our observations to the human system and to non-neuronal cells, we introduced the oncogenic form of p21 Ras into the cytoplasm of three different types of cultured human embryonic neural crest derivatives (8th-11th gestational week): dorsal root ganglion neurons, sympathetic neurons, and adrenal chromaffin cells. These cells are dependent on nerve growth factor for survival and/or fibre outgrowth in vitro. In dorsal root ganglion neurons, p21 Ras promoted survival and fibre outgrowth which was quantitatively and qualitatively comparable to the nerve growth factor effect (84% vs. 95%, control 18%). Sympathetic neurons showed a similar effect, albeit with a higher background survival (91% vs. 93%, control 58%). On chromaffin cells, which respond to nerve growth factor with pronounced fibre outgrowth in culture, the effect of p21 Ras was again comparable to that of nerve growth factor (35% vs. 30%, control 5%). The survival and fibre outgrowth-promoting effects of p21 Ras on human embryonic dorsal root ganglion neurons, sympathetic neurons and chromaffin cells suggest an involvement of p21 Ras in the intracellular signal transduction of nerve growth factor in human neural crest-derived cell populations.

Myocardial kinetics of TcN-NOET: a neutral lipophilic complex tracer of regional myocardial blood flow.

UNLABELLED: [Bis (N-etoxy, N ethyl dithiocarbamato) nitrido] 99mTc (V) (TcN-NOET) is a new neutral lipophilic myocardial imaging agent proposed for clinical use for detecting coronary artery disease. We studied the relation between myocardial retention of TcN-NOET and myocardial blood flow (MBF) in a canine model. METHODS: A wide range of MBF was induced by partial regional coronary occlusion and dipyridamole infusion (protocols 1,2 and 3). Myocardial activity of TcN-NOET was determined by in vitro tissue counting at 15 or 90 min postinjection. Tracer activity was correlated with radiolabeled microspheres using linear regression analysis. RESULTS: There was a linear correlation between myocardial TcN-NOET activity and microspheres in protocol 1 (r = 094, 15 min postinjection, protocol 2 (r = 0.94, 15 min postinjection after dipyridamole) and protocol 3 (r = 0.91, 90 min postinjection after dipyridamole). When arterial occlusion was discontinued (protocol 4), there was no longer a close linear correlation (r = 0.26). The first-pass myocardial extraction action of TcN-NOET was 75.5% +/- 4% under basal conditions and 85% +/- 2% under hyperemic conditions (p < 0.01). CONCLUSION: Up to 90 min after injection, the relationship between TcN-NOET myocardial retention and blood flow is excellent over a wide range of flows. After reflow, TcN-NOET redistributes almost completely within 90 min.

GangliosideGM1 expression during human spinal cord and neural crest development.

GangliosideGM1 represents a widespread component of the neural cell plasma membranes. Cholera toxin-B subunit binds selectively to GM1. Human spinal cords at post-conception (PC) weeks 6 to 11 were examined and early GM1 expression shown on the cell plasma membrane in the developing grey matter at PC week 6. GM1 was demonstrated also in the marginal layer (white matter); on neural crest derivative plasma membrane, i.e. dorsal root (DRG) and sympathetic ganglia; along emerging fibres from DRG and neurite terminals innervating skeletal muscle. GangliosideGM1 is highly expressed in spinal cord primary cultures and is a stringent neural cell marker. GangliosideGM1 represents an early marker of neural differentiation in both spinal cord and neural crest derivatives.

Experimental models, protocols, and reference values for evaluation of iodinated analogues of glucose.

For an iodinated analogue of glucose to be useful for evaluating glucose uptake using single-photon emission computed tomography (SPECT), it must enter the cell via the same transporter as glucose and accumulate within the cell without being degraded. The biological behavior of the iodinated tracer must therefore be similar to that of 2-deoxy-D(-)[1-14C]-glucose (2-DG). In the present study, four experimental models (biodistribution in mouse, isolated rat heart, human erythrocytes in suspension and cultured neonatal rat cardiomyocytes) have been chosen and protocols have been set up which allow for the examination of small quantities of iodinated analogues of glucose. The uptakes of 2-DG and of L(-)[1-14C]-glucose have been measured in these models to establish reference values which will be compared with uptake values for iodinated analogues of glucose.

Biological evaluation of two iodine-123-labeled D-glucose acetals prepared as glucose transporter radioligands.

Two iodinated acetals of D-glucose, 4,6-(R)-O-(2'-iodoethylidene)-alpha, beta-D-glucose (1) and 4,6-(R)-O-(4'-iodobenzylidene)-alpha, beta-D-glucose (2), were prepared and their potential as suitable SPECT radioligands for imaging of glucose transporters was studied. Both are analogs of acetal D-glucose derivatives, which are known to bind to the exofacial sites of the glucose transport protein (GluT). To assess whether iodinated acetals 1 and 2 interacted with the glucose transporter, they were tested in vitro in human erythrocytes (GluT1) and neonatal rat cardiomyocytes (GluT4). The results indicated that 1 and 2 had a very low affinity for the glucose transporter and probably accumulated in cells. Study of their tissue distribution was carried out in the mouse in vivo: Both compounds showed fast tissue clearance with preferential renal elimination. It is concluded that iodinated acetals of D-glucose 1 and 2 are not suitable for GluT targeting in vivo.

Biological evaluation of two anomeric glucose analogues iodinated in position 6.

Two anomeric analogues of glucose labelled with 123 iodine in position 6, proposed as tracers of glucose transport in vivo, have been synthesized: alpha- and beta-methyl-6-deoxy-6-iodo-D-glucopyranoside (alpha MDIG and beta MDIG). The aim of this study was to determine whether these molecules interact with the glucose transporter and whether they could be used as tracers of glucose transport in vivo. The biodistribution of alpha MDIG and beta MDIG was studied in the mouse in vivo. To determine if these two anomers enter the cell via the glucose transporter, their uptake was measured in isolated perfused rat hearts, in human erythrocytes in suspension, and in cardiomyocytes of neonatal rat in culture. Both alpha MDIG and beta MDIG had similar repartitions in the mouse: myocardial uptake averaged 7% of the injected dose/g of organ at 2 min postinjection and alpha MDIG competed with D-glucose to enter the cells. Insulin produced a 123% increase of its uptake in isolated perfused rat hearts and a 100% increase in cardiomyocytes of neonatal rat in culture. alpha MDIG uptake was lowered in the presence of glucose transport inhibitors in each experimental model. An interaction between beta MDIG and glucose transporters was observed only in human erythrocytes in suspension. Only alpha MDIG interacts with the glucose transporter, and thus could be used to estimate glucose transport in vivo.

[123I]-6-deoxy-6-iodo-D-glucose (6DIG): a potential tracer of glucose transport.

A glucose analogue labelled with iodine-123 in position 6 has been synthesized: [123I]-6-deoxy-6-iodo-D-glucose (6DIG). The aim of this study was to examine its biological behaviour in order to assess whether it could be used to evaluate glucose transport with SPECT. To establish whether 6DIG enters the cells using the glucose transporter, four biological models have been used: human erythrocytes in suspension, neonatal rat cardiomyocytes in culture, isolated perfused rat hearts, and biodistribution in mice. 6DIG competed with D-glucose to enter the cells and its entry was increased by insulin and inhibited in the presence of cytochalasin B. The biological behaviour of 6DIG was similar to that of 3-O-methyl-D-glucose. 6DIG is a tracer of glucose transport which is very promising for clinical studies.

Biological studies of analogues of glucose iodinated in positions 1, 2, or 3.

Analogues of glucose labeled with 123 iodine in positions 1, 2 or 3 have been synthesized. The aim of this study was to examine their biological behavior in four experimental models in order to assess whether they could be used to evaluate the uptake of glucose with single photon emission computed tomography (SPECT). The results obtained have shown that none of these molecules enters the cell using the glucose transporter. Therefore, they cannot be used as tracers of glucose uptake.

[Comparative clinical study of a new imidazole molecule (fluconazole) and ketaconazole in the treatment of Candida albicans vulvovaginitis]. / Studio clinico comparato tra una nuova molecola imidazolica (fluconazolo) e il ketoconazolo nella terapia della vulvovaginite da Candida albicans.

A multicentre trial was carried out in Italy with the aim of comparing the efficacy, safety and tolerability of the oral administration of fluconazole with the oral administration of ketoconazole in the treatment of patients affected by Candida vulvovaginitis. A total of 174 patients with symptomatic Candida vulvovaginitis were identified both by objective examination and cell culture tests: of these 87 were treated using a single oral administration of fluconazole (150 mg) whereas the other 87 received 2 200 mg capsules of ketoconazole daily for 5 days. Tests to assess the efficacy, safety and tolerability of both treatments were carried out approximately 7 days and 5-6 weeks from the start of therapy. The results obtained showed a success rate of 92% for fluconazole-treated patients and 83% for those treated with ketoconazole. In addition to the rapid and safe efficacy of treatment, the most important findings which emerged from this study were the extreme simplicity of use, excellent patient compliance and the complete absence of collateral effects of variations in the hematochemical and urine parameters taken into consideration caused by fluconazole.