Respiratory failure due to COVID-19 pneumonia is associated with high mortality and may overwhelm health care systems, due to the surge of patients requiring advanced respiratory support. Shortage of ...intensive care unit (ICU) beds required many patients to be treated outside the ICU despite severe gas exchange impairment. Helmet is an effective interface to provide continuous positive airway pressure (CPAP) noninvasively. We report data about the usefulness of helmet CPAP during pandemic, either as treatment, a bridge to intubation or a rescue therapy for patients with care limitations (DNI).
In this observational study we collected data regarding patients failing standard oxygen therapy (i.e., non-rebreathing mask) due to COVID-19 pneumonia treated with a free flow helmet CPAP system. Patients' data were recorded before, at initiation of CPAP treatment and once a day, thereafter. CPAP failure was defined as a composite outcome of intubation or death.
A total of 306 patients were included; 42% were deemed as DNI. Helmet CPAP treatment was successful in 69% of the full treatment and 28% of the DNI patients (P < 0.001). With helmet CPAP, PaO
/FiO
ratio doubled from about 100 to 200 mmHg (P < 0.001); respiratory rate decreased from 28 22-32 to 24 20-29 breaths per minute, P < 0.001). C-reactive protein, time to oxygen mask failure, age, PaO
/FiO
during CPAP, number of comorbidities were independently associated with CPAP failure. Helmet CPAP was maintained for 6 3-9 days, almost continuously during the first two days. None of the full treatment patients died before intubation in the wards.
Helmet CPAP treatment is feasible for several days outside the ICU, despite persistent impairment in gas exchange. It was used, without escalating to intubation, in the majority of full treatment patients after standard oxygen therapy failed. DNI patients could benefit from helmet CPAP as rescue therapy to improve survival.
NCT04424992.
The
gene encodes a 30-zinc-finger transcription factor involved in key developmental pathways. Although null
mutants develop cerebellar malformations, the underlying mechanism remains unknown.
...mutations are associated with Joubert Syndrome, a ciliopathy causing cerebellar vermis hypoplasia and ataxia.
participates in the DNA-damage response (DDR), raising questions regarding its role as a regulator of neural progenitor cell cycle progression in cerebellar development. To characterize
the function of ZFP423 in neurogenesis, we analyzed allelic murine mutants in which distinct functional domains are deleted. One deletion impairs mitotic spindle orientation, leading to premature cell cycle exit and Purkinje cell (PC) progenitor pool deletion. The other deletion impairs PC differentiation. In both mutants, cell cycle progression is remarkably delayed and DDR markers are upregulated in cerebellar ventricular zone progenitors. Our
evidence sheds light on the domain-specific roles played by ZFP423 in different aspects of PC progenitor development, and at the same time strengthens the emerging notion that an impaired DDR may be a key factor in the pathogenesis of JS and other ciliopathies.
The antithrombin (AT) binding properties of heparin and low molecular weight heparins are strongly associated to the presence of the pentasaccharide sequence AGA*IA ...(A(NAc,6S)-GlcUA-A(NS,3,6S)-I(2S)-A(NS,6S)). By using the highly chemoselective depolymerization to prepare new ultra low molecular weight heparin and coupling it with the original separation techniques, it was possible to isolate a polysaccharide with a biosynthetically unexpected structure and excellent antithrombotic properties. It consisted of a dodecasaccharide containing an unsaturated uronate unit at the nonreducing end and two contiguous AT-binding sequences separated by a nonsulfated iduronate residue. This novel oligosaccharide was characterized by NMR spectroscopy, and its binding with AT was determined by fluorescence titration, NMR, and LC-MS. The dodecasaccharide displayed a significantly increased anti-FXa activity compared with those of the pentasaccharide, fondaparinux, and low molecular weight heparin enoxaparin.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The 3-O-sulfation of N-sulfated glucosamine is the last event in the biosynthesis of heparin/heparan sulfate, giving rise to the antithrombin-binding pentasaccharide sequence AGA*IA, which is largely ...associated with the antithrombotic activity of these molecules. The aim of the present study was the structural and biochemical characterization of a previously unreported AGA*IA*-containing octasaccharide isolated from the very-low-molecular-mass heparin semuloparin, in which both glucosamine residues of the pentasaccharide moiety located at the non-reducing end bear 3-O-sulfate groups. Two-dimensional and STD (saturation transfer difference) NMR experiments clearly confirmed its structure and identified its ligand epitope binding to antithrombin. The molecular conformation of the octasaccharide-antithrombin complex has been determined by NMR experiments and docking/energy minimization. The presence of the second 3-O-sulfated glucosamine in the octasaccharide induced more than one order of magnitude increase in affinity to antithrombin compared to the pentasaccharide AGA*IA.
Terminal 1,6-anhydro-aminosugars (1,6-anAS) are typical structural moieties of enoxaparin, a low-molecular-weight heparin (LMWH) widely used for prevention and treatment of thrombotic disorders. In ...the enoxaparin manufacturing process, these modified amino sugars are formed during the β-eliminative cleavage of heparin. To investigate the effect of terminal anAS on antithrombin (AT) binding and on inhibition of factor Xa (FXa), two octasaccharides containing modified AT-binding pentasaccharide sequences were isolated from enoxaparin. The molecular conformation of the octasaccharides terminating with N-sulfo-1,6-anhydro-d-mannosamine and N-sulfo-1,6-anhydro-d-glucosamine, respectively, has been determined both in the absence and presence of AT by NMR experiments and docking simulations. Reduced overall contacts of the terminal anAS residues with the binding region of AT induce a decrease in affinity for AT as well as lower anti-FXa activity. The anti-FXa measured either in buffer or plasma milieu does not show any significant difference, suggesting that the inhibition of anti-FXa remains specific and biologically relevant.
Benchmark analysis for open liver surgery for cirrhotic patients with hepatocellular carcinoma (HCC) is still undefined.
Patients were identified from the Italian national registry HE.RC.O.LE.S. The ...Achievable Benchmark of Care (ABC) method was employed to identify the benchmarks. The outcomes assessed were the rate of complications, major comorbidities, post-operative ascites (POA), post-hepatectomy liver failure (PHLF), 90-day mortality. Benchmarking was stratified for surgical complexity (CP1, CP2 and CP3).
A total of 978 of 2698 patients fulfilled the inclusion criteria. 431 (44.1%) patients were treated with CP1 procedures, 239 (24.4%) with CP2 and 308 (31.5%) with CP3 procedures. Patients submitted to CP1 had a worse underlying liver function, while the tumor burden was more severe in CP3 cases. The ABC for complications (13.1%, 19.2% and 28.1% for CP1, CP2 and CP3 respectively), major complications (7.6%, 11.1%, 12.5%) and 90-day mortality (0%, 3.3%, 3.6%) increased with the surgical difficulty, but not POA (4.4%, 3.3% and 2.6% respectively) and PHLF (0% for all groups).
We propose benchmarks for open liver resections in HCC cirrhotic patients, stratified for surgical complexity. The difference between the benchmark values and the results obtained during everyday practice reflects the room for potential growth, with the aim to encourage constant improvement among liver surgeons.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The first use of statistical correlation spectroscopy to extract chemical information from 2D-HSQC spectra, termed HSQC correlation spectroscopy (HSQCcos), is reported. HSQCcos is illustrated using ...heparin, a heterogeneous polysaccharide, whose diverse composition causes signals in HSQC spectra to disperse. HSQCcos has been used to probe the chain modifications that cause this effect and reveals hitherto unreported structural details. An interesting finding was that the signal for position 2 of trisulfated glucosamine N-, 3-O-, and 6-O-sulfated (A*) is bifurcated, owing to the presence of A* residues in both the “normal” antithrombin binding site and also at the nonreducing end of the molecule, which is reported in intact heparin for the first time. The method was also applied to investigating the environment around other rare sequences/disaccharides, suggesting that the disaccharide; 2-O-sulfated iduronic acid linked to 6-O-sulfated N-glucosamine, which contains a free amine at position 2, is adjacent to the heparin linkage region. HSQCcos can extract chemically related signals from information-rich spectra obtained from complex mixtures such as heparin.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
The antithrombin (AT) binding properties of heparin and low molecular weight heparins are strongly associated to the presence of the pentasaccharide sequence AGA*IA ...(ANAc,6S-GlcUA-ANS,3,6S-I2S-ANS,6S). By using the highly chemoselective depolymerization to prepare new ultra low molecular weight heparin and coupling it with the original separation techniques, it was possible to isolate a polysaccharide with a biosynthetically unexpected structure and excellent antithrombotic properties. It consisted of a dodecasaccharide containing an unsaturated uronate unit at the nonreducing end and two contiguous AT-binding sequences separated by a nonsulfated iduronate residue. This novel oligosaccharide was characterized by NMR spectroscopy, and its binding with AT was determined by fluorescence titration, NMR, and LC-MS. The dodecasaccharide displayed a significantly increased anti-FXa activity compared with those of the pentasaccharide, fondaparinux, and low molecular weight heparin enoxaparin.
Background: Heparin is a linear sulfated polysaccharide used clinically as an anticoagulant.
Results: A heparin dodecasaccharide, containing two contiguous antithrombin-binding sequences, has been described and characterized for the first time.
Conclusion: The dodecasaccharide binds antithrombin in two different molecular assemblies enhancing the probability of the binding and the affinity.
Significance: The discovery of this dodecasaccharide improves the knowledge of heparin structure.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Burkholderia pseudomallei is the etiological agent of melioidosis, a severe endemic disease in South-East Asia, causing septicemia and organ failure with high mortality rates. Current treatments and ...diagnostic approaches are largely ineffective. The development of new diagnostic tools and vaccines toward effective therapeutic opportunities against B. pseudomallei is therefore an urgent priority. In the framework of a multidisciplinary project tackling melioidosis through reverse and structural vaccinology, BPSL1050 was identified as a candidate for immunodiagnostic and vaccine development based on its reactivity against the sera of melioidosis patients. We determined its NMR solution structure and dynamics, and by novel computational methods we predicted immunogenic epitopes that once synthesized were able to elicit the production of antibodies inducing the agglutination of the bacterium and recognizing both BPSL1050 and B. pseudomallei crude extracts. Overall, these results hold promise for novel chemical biology approaches in the discovery of new diagnostic and prophylactic tools against melioidosis.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM, UPUK
BPSL1050 is a 13.9 kDa protein produced by the Gram-negative bacterium Burkholderia pseudomallei, the etiological agent of melioidosis. Immunodetection assays against sera patients using protein ...microarray suggest BPSL1050 involvement in melioidosis. Herein we report its backbone and side chains NMR assignment.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
PDF
