Ventilatory efficiency in long-term dyspnoeic patients following COVID-19 pneumonia.

BACKGROUND: Long COVID is defined as persistency of symptoms, such as exertional dyspnea, twelve weeks after recovery from SARS-CoV-2 infection. OBJECTIVES: To investigate ventilatory efficiency by the use of cardiopulmonary exercise testing (CPET) in patients with exertional dyspnea despite normal basal spirometry after 18 (T18) and 36 months (T36) from COVID-19 pneumonia. METHODS: One hundred patients with moderate-critical COVID-19 were prospectively enrolled in our Long COVID program. Medical history, physical examination and lung high-resolution computed tomography (HRCT) were obtained at hospitalization (T0), 3 (T3) and 15 months (T15). All HRCTs were revised using a semi-quantitative CT severity score (CSS). Pulmonary function tests were obtained at T3 and T15. CPET was performed in a subset of patients with residual dyspnea (mMRC ≥ 1), at T18 and at T36. RESULTS: Remarkably, at CPET, ventilatory efficiency was reduced both at T18 (V'E/V'CO2 slope = 31.4±3.9 SD) and T36 (V'E/V'CO2 slope = 31.28±3.70 SD). Furthermore, we identified positive correlations between V'E/V'CO2 slope at T18 and T36 and both percentage of involvement and CSS at HRCT at T0, T3 and T15. Also, negative linear correlations were found between V'E/V'CO2 slope at T18 and T36 and DLCO at T3 and T15. CONCLUSIONS: At eighteen months from COVID-19 pneumonia, 20 % of subjects still complains of exertional dyspnea. At CPET this may be explained by persistently reduced ventilatory efficiency, possibly related to the degree of lung parenchymal involvement in the acute phase of infection, likely reflecting a damage in the pulmonary circulation.

Effective treatment with oral Salbutamol on late onset respiratory impairment in a DOK7 Congenital Myasthenia Syndrome: a case report.

INTRODUCTION: DOK7 gene deficiency is a neuromuscular disease with an alteration in post-synaptic neuromuscular junction, leading to progressive respiratory impairment. Although, the therapy is not standardized, adrenergic agonists are suggested as first-line treatment.  Case presentation: Our patient had an ambiguous late childhood-onset and had a generalized muscle weakness free of respiratory symptoms during the early phase of the disease. Subsequently, when the respiratory muscle and the diaphragm involvement was impaired, a substantial loss of respiratory function with hypopneas and severe desaturation was detected. It was noteworthy the striking respiratory beneficial impact of oral salbutamol in the resolution of symptoms and functional impairments, leading to a remarkable respiratory improvement and a better quality of life.  Conclusion: Oral salbutamol treatment combined to a timely clinical recognition led to an outstanding respiratory improvement.

Stereoselective Shi-type epoxidation with 3-oxo-4,6-O-benzylidene pyranoside catalysts: unveiling the role of carbohydrate skeletons.

Asymmetric epoxidation represents a hot topic in organic synthesis. In recent years, organocatalysts based on sugar skeletons have been exploited in asymmetric epoxidation to achieve enantiomeric pure epoxides. In this work, two different endocyclic ketones derived from glucose and galactose protected with a 4,6-O-benzylidene group have been prepared and exploited for Shi-type epoxidation. The two carbohydrates show an opposite preferential stereoselective epoxidation on various olefins, affording the epoxides in high conversions and modest enantioselectivities. DFT calculations disclosed the reasons behind the inversion of selectivity achieved by the two catalysts, showing that a delicate balance between the catalyst conformation, its protecting groups, and the secondary interactions with the substrate govern the final observed results.

Early Stage In Vitro Bioprofiling of Potential Low-Molecular-Weight Organoboron Compounds for Boron Neutron Capture Therapy (BNCT)-Proposal for a Guide.

Given the renewed interest in boron neutron capture therapy (BNCT) and the intensified search for improved boron carriers, as well as the difficulties of coherently comparing the carriers described so far, it seems necessary to define a basic set of assays and standardized methods to be used in the early stages of boron carrier development in vitro. The selection of assays and corresponding methods is based on the practical experience of the authors and is certainly not exhaustive, but open to discussion. The proposed tests/characteristics: Solubility, lipophilicity, stability, cytotoxicity, and cellular uptake apply to both low molecular weight (up to 500 Da) and high molecular weight (5000 Da and more) boron carriers. However, the specific methods have been selected primarily for low molecular weight boron carriers; in the case of high molecular weight compounds, some of the methods may need to be adapted.

Iodine-triphenylphosphine triggers an easy one-pot alpha stereoselective dehydrative glycosylation on hemiacetalic benzylated glycosyl donors.

The discovery of new glycosylation reactions is still a major challenge in carbohydrate chemistry. Traditional glycosylation reactions require the preparation of sugar donors with anomeric active or latent leaving groups. Dehydrative glycosylation is a fascinating alternative that enables the direct formation of the glycosidic bond from the hemiacetal, eliminating the need for (sometimes unstable) leaving groups, and allowing to reduce reaction, work-up, and purification times. Although some interesting methods of dehydrative glycosylation have been reported, in order to compete with conventional chemical glycosylation, a greater number of efficient and stereoselective methods need to be developed. Herein, a dehydrative procedure that uses a combination of iodine, triphenylphosphine, and a base (DMAP or imidazole) is described. This methodology allows for the preparation of sugar derivatives from commercially available 1-hydroxy glycosyl donors. The reaction takes place under mild conditions through the in situ-formation of an anomeric iodide intermediate, which, upon reaction with an alcohol, gives the corresponding glycosides up to quantitative yields and with high α-stereoselectivity.

Functionalization of ß-cyclodextrin with a urea-based PSMA ligand and preliminary studies on targeting prostate cancer cells.

Targeted delivery of drugs into specific cancer cells is an effective way to enhance the efficacy and minimize the side effects of therapy. Prostate malignant cells overexpress the prostate-specific membrane antigen (PSMA), a membrane protein that may be a valid target for selective drug administration. To target prostate cancer cells, a ß-cyclodextrin perfunctionalised with dipeptide-like urea arms, a well-established mimic of a selective ligand against PSMA, is herein reported, to develop a multivalent drug delivery and targeting system. Firstly, fluorescein was used to validate the system on cells that express high levels of PSMA (prostate tumoral cells, LNCap) or very low levels of PSMA (non-tumoral cells, Hek293T). Then, the antineoplastic agent doxorubicin complexed with ß-cyclodextrin functionalized with PSMA-like ligand takes less time to induce cytotoxicity on LNCap cells compared to doxorubicin alone. This might represent a promising drug-delivery approach to selectively target prostate cancer cells.

Unusual promoters and leaving groups in glycosylation reactions: The evolution of carbohydrate synthesis.

Glycosylation is the key reaction by which our body can produce and modify carbohydrates and their conjugates which are molecules essential for life. The study of the diversity of their functions is a current and ever-expanding topic that requires the ability to provide pure saccharides quickly, efficiently and in a controlled way which can be achieved by chemical synthesis. Although the influence of the donor and the promoter on the outcome of a glycosylation reaction is well documented, the search for new methodologies and new promoters/activators is constantly expanding. In this review, after an introduction dealing with well-known glycosylation strategies, we describe the most recent advances in terms of the use of innovative approaches, focalizing the study on new promoters and leaving groups exploited in the last ten years.

Synthesis, equilibrium, and biological study of a C-7 glucose boronic acid derivative as a potential candidate for boron neutron capture therapy.

The synthesis of d-glucoheptose derivative containing a boronic moiety is described herein. Starting from benzyl 6,7-dideoxy-2,3,4-tri-O-benzyl-ß-d-gluco-ept-6-enopyranoside, the introduction of the boronic acid was performed through a metathesis reaction by using MIDA vinyl boronic acid and the 2nd generation Grubbs catalyst. Hydrogenation led to the final product in only two reaction steps. This new sugar-containing boronic acid in the skeleton could mimic carbohydrate behavior and follow the glucose uptake in living cells. The in vitro toxicity tests performed in fibroblasts and glioma tumor cell lines showed minimal toxicity. Boron uptake measured using ICP-MS was minimal in fibroblasts, while in glioma cells showed a value of 6 ng of total boron accumulation per mg of cells, implying that compound 1a is able to accumulate selectively in the tumor tissues compared to normal.

Organotrifluoroborate Sugar Conjugates for a Guided Boron Neutron Capture Therapy: From Synthesis to Positron Emission Tomography.

Sugars are a versatile tool for targeting malignant cells and have been extensively used for drug delivery and imaging techniques. Their prototype, fluorodeoxyglucose ([18F]FDG), is currently used for positron emission tomography. Boron neutron capture therapy (BNCT) is a cancer treatment that relies on irradiation with thermal neutrons of cancer cells previously loaded with [10B]-containing compounds. The recent introduction of accelerators as a neutron source for clinical use prompts the planning of delivery compounds enriched with boron able to be traced in real time. This work describes the first synthesis of a new class of sugar derivatives conjugated to a trifluoroborate moiety as potential theranostic agents. Stability and cytotoxicity studies are reported for all compounds, together with [18F] radiolabeling optimization and in vivo preliminary positron emission tomography (PET) experiments on a selected compound.

Exploring glycosyl sulphates as donors for chemical glycosylation.

The preparation of anomeric tetrabutylammonium sulphates of glucose and galactose derivatives is reported and their role as donors in glycosylation reactions is studied. Metal triflates showed good performance in activating sulphate as a leaving group. Among them, ytterbium triflate in stoichiometric amounts gave the best results. Basic conditions using barium oxide in combination with trimethylsilyl trifluoromethanesulfonate (TMSOTf) were also shown to give good results. Benzylated sulphates were much more reactive than benzoylated donors when activated either by ytterbium triflate or by BaO and TMSOTf. Different acceptors were tested, such as isopropanol, cholesterol, and other common sugar derivatives. High reaction rates and excellent glycosylation yields were obtained under mild reaction conditions. The α/ß anomeric ratio suggests a predominant SN2-like reaction mechanism.

Theranostics in Boron Neutron Capture Therapy.

Boron neutron capture therapy (BNCT) has the potential to specifically destroy tumor cells without damaging the tissues infiltrated by the tumor. BNCT is a binary treatment method based on the combination of two agents that have no effect when applied individually: 10B and thermal neutrons. Exclusively, the combination of both produces an effect, whose extent depends on the amount of 10B in the tumor but also on the organs at risk. It is not yet possible to determine the 10B concentration in a specific tissue using non-invasive methods. At present, it is only possible to measure the 10B concentration in blood and to estimate the boron concentration in tissues based on the assumption that there is a fixed uptake of 10B from the blood into tissues. On this imprecise assumption, BNCT can hardly be developed further. A therapeutic approach, combining the boron carrier for therapeutic purposes with an imaging tool, might allow us to determine the 10B concentration in a specific tissue using a non-invasive method. This review provides an overview of the current clinical protocols and preclinical experiments and results on how innovative drug development for boron delivery systems can also incorporate concurrent imaging. The last section focuses on the importance of proteomics for further optimization of BNCT, a highly precise and personalized therapeutic approach.

Gentianose: Purification and structural determination of an unknown oligosaccharide in grape seeds.

Grape seeds are among the main constituents of grape pomace, ranging between 20% and 30% of the wet matrix; however, their oligosaccharide composition has not been studied. This paper describes the purification and the identification of low molecular weight oligosaccharides contained in an EtOH/water extract of grape seeds. A sequential two-step purification by size exclusion chromatography was carried out to fractionate compounds according to molecular weights. Chemical characterization of the combined fractions was performed by Magnetic Resonance Spectroscopy and Gas Chromatography-Mass Spectrometry analyses. The separation process gave two fractions abundant in sucrose and glucose. A third fraction containing trisaccharides was acetylated allowing the purification of the main trisaccharide. The structure elucidation of the acetylated product made it possible to identify gentianose, a predominant carbohydrate reserve found in the storage roots of perennial Gentiana lutea. Grape seeds are wine industry by-products and the obtained results suggest the importance of their recovery.

Carotid Thrombosis in a Crack Cocaine Smoker Woman.

INTRODUCTION: We report a case of stroke in a crack smoker with occlusion of the middle cerebral artery and a large thrombus in the carotid artery. Case Presentation. A 34-year-old female presented with left upper arm weakness, associated with paresthesia with onset of symptoms more than 24 hours before. Angio-RM sequences showed an area of ischemia, with occlusion of the M2 segment of the middle cerebral artery. Carotid ultrasound showed a soft plaque with distal end floating. Anticoagulant treatment was started, and seriated ultrasound evaluations showed its gradual dissolution. CONCLUSIONS: In atherothromboembolic stroke from carotid thrombosis, repeated ultrasound studies may be useful for either diagnosis and monitoring the efficacy of anticoagulant therapy.

[Ictus dopo una seduta dal parrucchiere.] / Stroke after a visit to hairdresser.

Riassunto. Le dissecazioni delle arterie cervicali (DAC) sono una causa inusuale di ictus ma il loro tasso di prevalenza cresce fino al 20% nella fascia di età giovane-adulta. In molti casi le dissecazioni si associano a rare malattie connettivali come la sindrome di Ehlers-Danlos, di Marfan, la fibrodisplasia. I fattori di rischio esterni principali sono rappresentati da bruschi traumi cervicali come negli incidenti stradali o, meno frequentemente, da procedure meno cruente come la manipolazione e l'iperestensione prolungata del collo. Diversi casi di DAC sono presenti in letteratura dopo sedute chiropratiche, procedure odontoiatriche ed endoscopiche. Noi riportiamo un insolito caso di dissecazione della carotide interna di sinistra causata da iperestensione del collo occorsa dopo uno shampoo dal parrucchiere.

Anomeric sugar boronic acid analogues as potential agents for boron neutron capture therapy.

After the development of accelerators as neutron source, the access to new suitable agents for boron neutron capture therapy (BNCT) became a major need. Among many others, sugar boronic acids have recently attracted attention as boron carriers. Herein we report the synthesis and preliminary biological studies of two new sugar analogues containing a boronic acid at the anomeric position. The analogues were obtained by hydroboration of proper open-chain terminal alkenes that, after quenching with water, spontaneously afforded cyclic boronic acids with hemiacetal-like structures.

A versatile synthesis of αGalCer and its analogues exploiting a cyclic carbonate as phytosphingosine 3,4-diol protecting group.

A convenient synthetic strategy to αGalCer and some relevant analogues by using a handily protected phytosphingosine is reported here. The conversion of the phytosphingosine amino group to azide and the protection of 3,4-diol as cyclic carbonate group, cleavable in mild basic conditions but resistant to acidic treatment, afforded quickly an excellent glycosyl acceptor. Its glycosylation with a proper galactosyl donor, gave a versatile intermediate in high yield and excellent stereoselectivity. To demonstrate the potentiality of the intermediate, three immunologically relevant compounds were chosen as model targets: αGalCer, dansyl alpha-galactosylceramide and 7DW8-5. These products were easily obtained in few steps and high yields to validate the synthetic route.

Properties, metabolism and roles of sulfogalactosylglycerolipid in male reproduction.

Sulfogalactosylglycerolipid (SGG, aka seminolipid) is selectively synthesized in high amounts in mammalian testicular germ cells (TGCs). SGG is an ordered lipid and directly involved in cell adhesion. SGG is indispensable for spermatogenesis, a process that greatly depends on interaction between Sertoli cells and TGCs. Spermatogenesis is disrupted in mice null for Cgt and Cst, encoding two enzymes essential for SGG biosynthesis. Sperm surface SGG also plays roles in fertilization. All of these results indicate the significance of SGG in male reproduction. SGG homeostasis is also important in male fertility. Approximately 50% of TGCs become apoptotic and phagocytosed by Sertoli cells. SGG in apoptotic remnants needs to be degraded by Sertoli lysosomal enzymes to the lipid backbone. Failure in this event leads to a lysosomal storage disorder and sub-functionality of Sertoli cells, including their support for TGC development, and consequently subfertility. Significantly, both biosynthesis and degradation pathways of the galactosylsulfate head group of SGG are the same as those of sulfogalactosylceramide (SGC), a structurally related sulfoglycolipid important for brain functions. If subfertility in males with gene mutations in SGG/SGC metabolism pathways manifests prior to neurological disorder, sperm SGG levels might be used as a reporting/predicting index of the neurological status.

Optimizing adjuvants for intradermal delivery of MenC glycoconjugate vaccine.

Intradermal vaccine delivery is a promising alternative to the conventional intramuscular route. The skin layer is immunologically supported by a densely network of antigen presenting cells, while the skeletal muscle is loaded with a relatively sparse population of APCs. Nevertheless, the vaccine to be suitable for intradermal delivery needs a new formulation to facilitate either smaller injection volumes or the introduction into new delivery devises as micro-needles. This study presents a proof of concept for intradermal delivery of the MenC-CRM197 glycoconjugate vaccine using a mouse model. Tangential flow filtration allowed obtaining a 20-fold concentrated vaccine formulation suitable for intradermal injection. Importantly the intradermal delivery of non-adjuvanted MenC glycoconjugate vaccine showed a quicker on-set and superiority in terms of immunogenicity compared to intramuscular administration of the respective vaccine and comparable immunogenicity to the aluminum adjuvanted vaccine formulation given intramuscular. Subsequently, the use of adjuvants allowed to further increase the immunogenicity and to modulate the quality of the immune response towards a more beneficial Th1 response. As adjuvants two Toll like receptor agonists (TLR4a and TLR7a), a mutant of the heat-labile enterotoxin from Escherichia coli (LT), a α-GalactosylCeramide analogue and an oil in water emulsion were investigated in order to target skin-resident antigen-presenting cells. This approach has the potential to be extended to other meningococcal serogroups, representing a promising strategy for the development of dermally administered multivalent glycoconjugate vaccines.

Synthesis of Sugar-Boronic Acid Derivatives: A Class of Potential Agents for Boron Neutron Capture Therapy.

To date, sugar analogues that contain boronic acids as substitutes for hydroxyl groups are a class of compounds nearly unknown in the literature. The challenging synthesis of two sugar-boronic acid analogues is described, and data are retrieved on their solution behavior, stability, and toxicity. As these compounds were expected to mimic the behavior of carbohydrates, they were tested in regards to their future development as potential boron neutron capture therapy agents.

An improved neutron autoradiography set-up for (10)B concentration measurements in biological samples.

AIM: Boron Neutron Capture Therapy (BNCT) is a binary hadrontherapy which exploits the neutron capture reaction in boron, together with a selective uptake of boronated substances by the neoplastic tissue. There is increasing evidence that future improvements in clinical BNCT will be triggered by the discovery of new boronated compounds, with higher selectivity for the tumor with respect to clinically used sodium borocaptate (BSH) and boronophenylalanine (BPA). BACKGROUND: Therefore, a (10)B quantification technique for biological samples is needed in order to evaluate the performance of new boronated formulations. MATERIALS AND METHODS: This article describes an improved neutron autoradiography set-up employing radiation sensitive films where the latent tracks are made visible by proper etching conditions. RESULTS: Calibration curves for both liquid and tissue samples were obtained. CONCLUSIONS: The obtained calibration curves were adopted to set-up a mechanism to point out boron concentration in the whole sample.