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Activation of water at disiladicarbene: from the perspective of modification of silicon surface with organo-silicon compounds
No full textSilicon is one of the most important components of electronic devices. Surface passivation of a silicon wafer is an active area of research. The Si(OH)2 sites of partially oxidized silicon surface could exist as hydroxylated [Si(OH)2] or hydrated silanone [SiO•(OH2)]. The previously reported disiladicarbene
(cAAC)2Si2 has been reacted here with water to obtain elusive, hydrated silanone (3) co-crystallized with its silanol analog (2) in a 1:3 molar ratio. The mass spectrometric characterization of acyclic silanone, followed by the isolation and characterization of the zwitterionic hydrated silanone, has been achieved. The detailed energy decomposition analysis coupled with natural orbital for chemical valence (EDA-NOCV) calculations revealed that the central Si(O)OH unit of the hydrated silanone possesses a covalent electron sharing r- and a dative r-bonds (CL-Si, Si/CL) with hydrogen-containing cyclic alkyl(amino) carbene ligands. These two bonds are stabilized by 49% coulombic interaction and 47.8% orbital interaction. The presence of N-atoms at the hydrogenated and/or protonated carbene part (cAACH/cAACH2) has reduced the stability of these species. The electron pair on the N-atom of the cAACH unit displays a sort of anomeric effect relevant to the cyclic form of the sugar molecule
Understanding, assessing and treating immune, endothelial and haemostasis dysfunctions in bacterial sepsis
No full textThe interplay between the immune system, coagulation, and endothelium is critical in regulating the host response to infection. However, in sepsis and other critical illnesses, a dysregulated immune response can lead to excessive alterations in these mechanisms, resulting in coagulopathy, endothelial dysfunction, and multi-organ dysfunction. This review aims to provide a comprehensive analysis of the pathophysiological mechanisms that govern the complex interplay between immune dysfunction, endothelial dysfunction, and coagulation in sepsis. It emphasises clinical significance, evaluation methods, and potential therapeutic interventions. Understanding these mechanisms is essential for developing effective treatments that can modulate the immune response, mitigate thrombosis, restore endothelial function, and ultimately improve patient survival
What is the definition of stone dust and how does it compare with clinically insignificant residual fragments? A comprehensive review
No full textPURPOSE
During endoscopic stone surgery, Holmium:YAG (Ho:YAG) and Thulium Fiber Laser (TFL) technologies allow to pulverize urinary stones into fine particles, ie DUST. Yet, currently there is no consensus on the exact definition of DUST. This review aimed to define stone DUST and Clinically Insignificant Residual Fragments (CIRF).
METHODS
Embase, MEDLINE (PubMed) and Cochrane databases were searched for both in vitro and in vivo articles relating to DUST and CIRF definitions, in November 2023, using keyword combinations: "dust", "stones", "urinary calculi", "urolithiasis", "residual fragments", "dusting", "fragments", "lasers" and "clinical insignificant residual fragments".
RESULTS
DUST relates to the fine pulverization of urinary stones, defined in vitro as particles spontaneously floating with a sedimentation duration ≥ 2 sec and suited for aspiration through a 3.6Fr-working channel (WC) of a flexible ureteroscope (FURS). Generally, an upper size limit of 250 µm seems to agree with the definition of DUST. Ho:YAG with and without "Moses Technology", TFL and the recent pulsed-Thulium:YAG (pTm:YAG) can produce DUST, but no perioperative technology can currently measure DUST size. The TFL and pTm:YAG achieve better dusting compared to Ho:YAG. CIRF relates to residual fragments (RF) that are not associated with imminent stone-related events: loin pain, acute renal colic, medical or interventional retreatment. CIRF size definition has decreased from older studies based on Shock Wave Lithotripsy (SWL) (≤ 4 mm) to more recent studies based on FURS (≤ 2 mm) and Percutaneous Nephrolithotomy(PCNL) (≤ 4 mm). RF 2 mm are associated with lower stone recurrence, regrowth and clinical events rates. While CIRF should be evaluated postoperatively using Non-Contrast Computed Tomography(NCCT), there is no consensus on the best diagnostic modality to assess the presence and quantity of DUST.
CONCLUSION
DUST and CIRF refer to independent entities. DUST is defined in vitro by a stone particle size criteria of 250 µm, translating clinically as particles able to be fully aspirated through a 3.6Fr-WC without blockage. CIRF relates to ≤ 2 RF on postoperative NCCT
Impact of successful secondary hyperparathyroidism treatment on cardiovascular morbidity in patients with chronic kidney disease KDIGO stages G3b-5
No full textINTRODUCTION
Chronic kidney disease is common, with a projected increase to 5.4 million people in need of kidney replacement therapy by 2030. As many as 61.7% of patients on hemodialysis have secondary hyperparathyroidism (SHPT). This has been associated with high cardiovascular morbidity. The present study investigates the effect of SHPT treatment success on cardiovascular morbidity in patients with CKD KDIGO stages G3b, 4, and 5.
METHODS
A retrospective single center analysis of 211 chronic kidney disease stages G3b-5 patients undergoing computed tomography for coronary artery calcium (CAC) scoring at the University Hospital of Zurich between 2015 and 2019 was performed. The presence of and control of SHPT was assessed at the timepoint of CAC scoring and 6-12 months prior. Information on left ventricular ejection fraction (LVEF), left ventricular hypertrophy (LVH), and left ventricular myocardial mass index (LVMMI) were calculated from echocardiography values obtained at the timepoint of CAC scoring. Occurrence of major acute cardiovascular events, including acute coronary syndrome (ACS), within 1 year of CAC scoring was drawn from the charts. Independent predictive factors for ACS and LVH were assessed by multivariable analysis.
RESULTS
Thirty-four percent (n=72) of the patients had uncontrolled SHPT, whereas 66% (n=139) had either no (n=18%, n=39) or a controlled SHPT (n=48%, n=100). The CKD stage G3b-5 patients with uncontrolled SHPT had a significantly lower LVEF (p=0.028) and significantly more pronounced LVH (p=0.003) and a higher LVMMI (p=0.002) than the group with either no SHPT or well-controlled SHPT. Uncontrolled SHPT in the observed CKD cohort had a significantly higher risk for developing ACS (p=0.011, HR 2.76, 95%CI 1.26-6.05) compared to no or controlled SHPT patients (41.7% vs 31.7%). While patients with uncontrolled SHPT showed a median CAC score of 290 (IQR 18-866), those with no or controlled SHPT had a lower median CAC score of 194 (IQR 14-869), although not significant (p=0.490). Patients with CAC scores >400 displayed a significantly higher incidence of ACS (56.8% vs 33.1%, p=0.010).
CONCLUSIONS
SHPT is common (82%) in advanced CKD (≥G3b) patients and insufficiently controlled in one-third of patients. Insufficient control of SHPT is associated with higher cardiovascular morbidity, lower LVEF, increased LVH, and a higher incidence of ACS. Thus, increased focus on SHPT control in CKD patients may have a beneficial impact on cardiovascular outcomes
Tinnitus and Vestibular Schwannoma
No full textVestibular schwannomas (VS) are associated with ipsilateral hearing loss (95%), tinnitus (70–80%), and disorders of balance (50%). However, unilateral hearing loss does not equate to a vestibular schwannoma. When an MRI scan is performed for unilateral hearing loss, in only 0.3% of patients, a VS is identified. Tinnitus is the principal symptom in 10% of VS patients, usually in very small or very large tumors, and is moderate to severe in 14% of individuals. It is mostly of high pitch.
Tinnitus improves when the cochlear nerve is transected, or hearing is saved during treatment. In general, microsurgery has better outcomes for tinnitus than stereotactic radiosurgery (SRS). This is likely related to the fact that after retrosigmoid and translabyrinthine, microsurgery tinnitus is often experienced as less troublesome than before the surgery
How many knots are necessary to achieve knot security of two high strength suture tapes? A biomechanical comparative analysis
No full textINTRODUCTION
According to current clinical practice, a minimum of 7 knots are required to provide secure hold in high-strength sutures. A new technology featuring a suture tape with a salt-infused silicon core has been recently developed, potentially reducing the number of needed knots.
AIMS
to (1) assess the influence of number of knots on tape security, (2) evaluate the effect of different ambient conditions on knot security, and (3) compare the biomechanical competence of the novel versus a conventional suture tape.
MATERIALS AND METHODS
A conventional suture tape (ST, SutureTape) was considered for knot tying together with the novel suture type (DT, Dynatape). Specimens were assigned to receive different number of knots, ranging from 3 to 7, and to be exposed to different media during tying-air (dry), saline solution (wet), and fat (fatty-wet). Seven specimens were considered for each suture type, knot number and ambient condition. With knotted sutures mounted between two roller bearings, quasi-static tensile ramp tests were performed to evaluate knot slippage, ultimate force at rupture, and minimum number of knots preventing suture unraveling for each suture tape and condition.
RESULTS
Whereas the ST ruptured without unraveling with a minimum of 6 knots in all specimens and ambient conditions, the minimum number of knots for a DT rupture without unraveling was 6 in dry, 4 in wet, and 5 in fatty-wet condition. Ultimate force at rupture with a minimum number of needed knots did not differ significantly between ST and DT (p ≥ 0.067), in contrast to knot slippage that was significantly bigger for ST versus DT in wet and fatty-wet conditions(p ≤ 0.001).
CONCLUSIONS
In fatty-wet conditions-related to open surgery-the novel Dynatape suture tape requires 5 instead of 7 knots to achieve their security. In wet conditions-related to arthroscopic surgery-this number can be reduced to 4 knots. In contrast, the conventional SutureTape needs 6 knots to provide security in all conditions
Viral and Host Factors Are Associated With Mortality in Hospitalized Patients With COVID-19
No full textBackground
Persistent mortality in adults hospitalized due to acute COVID-19 justifies pursuit of disease mechanisms and potential therapies. The aim was to evaluate which virus and host response factors were associated with mortality risk among participants in Therapeutics for Inpatients with COVID-19 (TICO/ACTIV-3) trials.
Methods
A secondary analysis of 2625 adults hospitalized for acute SARS-CoV-2 infection randomized to 1 of 5 antiviral products or matched placebo in 114 centers on 4 continents. Uniform, site-level collection of participant baseline clinical variables was performed. Research laboratories assayed baseline upper respiratory swabs for SARS-CoV-2 viral RNA and plasma for anti–SARS-CoV-2 antibodies, SARS-CoV-2 nucleocapsid antigen (viral Ag), and interleukin-6 (IL-6). Associations between factors and time to mortality by 90 days were assessed using univariate and multivariable Cox proportional hazards models.
Results
Viral Ag ≥4500 ng/L (vs <200 ng/L; adjusted hazard ratio [aHR], 2.07; 1.29–3.34), viral RNA (<35 000 copies/mL [aHR, 2.42; 1.09–5.34], ≥35 000 copies/mL [aHR, 2.84; 1.29–6.28], vs below detection), respiratory support (<4 L O2 [aHR, 1.84; 1.06–3.22]; ≥4 L O2 [aHR, 4.41; 2.63–7.39], or noninvasive ventilation/high-flow nasal cannula [aHR, 11.30; 6.46–19.75] vs no oxygen), renal impairment (aHR, 1.77; 1.29–2.42), and IL-6 >5.8 ng/L (aHR, 2.54 [1.74–3.70] vs ≤5.8 ng/L) were significantly associated with mortality risk in final adjusted analyses. Viral Ag, viral RNA, and IL-6 were not measured in real-time.
Conclusions
Baseline virus-specific, clinical, and biological variables are strongly associated with mortality risk within 90 days, revealing potential pathogen and host-response therapeutic targets for acute COVID-19 disease
An International Delphi Survey and Consensus Meeting to Define the Risk Factors for Ureteral Stricture after Endoscopic Treatment for Urolithiasis
No full textPURPOSE
Iatrogenic ureteral strictures (US) after endoscopic treatment for urolithiasis represent a significant healthcare concern. However, high-quality evidence on the risk factors associated with US is currently lacking. We aimed to develop a consensus statement addressing the definition, risk factors, and follow-up management of iatrogenic US after endoscopic treatment for urolithiasis.
METHODS
Utilizing a modified Delphi method, a steering committee developed survey statements based on a systematic literature review. Then, a two-round online survey was submitted to 25 experts, offering voting options to assess agreement levels. A consensus panel meeting was held for unresolved statements. The predetermined consensus threshold was set at 70%.
RESULTS
The steering committee formulated 73 statements. In the initial survey, consensus was reached on 56 (77%) statements. Following in-depth discussions and refinement of 17 (23%) statements in a consensus meeting, the second survey achieved consensus on 63 (86%) statements. This process underscored agreement on pivotal factors influencing US in endoscopic urolithiasis treatments.
CONCLUSIONS
This study provides a comprehensive list of categorized risk factors for US following endoscopic urolithiasis treatments. The objectives include enhancing uniformity in research, minimizing redundancy in outcome assessments, and effectively addressing risk factors associated with US. These findings are crucial for designing future clinical trials and guiding endoscopic surgeons in mitigating the risk of US