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1.
Commun Biol ; 7(1): 683, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38834871

ABSTRACT

In the context of soft matter and cellular mechanics, microrheology - the use of micron-sized particles to probe the frequency-dependent viscoelastic response of materials - is widely used to shed light onto the mechanics and dynamics of molecular structures. Here we present the implementation of active microrheology in an Acoustic Force Spectroscopy setup (AFMR), which combines multiplexing with the possibility of probing a wide range of forces ( ~ pN to ~nN) and frequencies (0.01-100 Hz). To demonstrate the potential of this approach, we perform active microrheology on biological samples of increasing complexity and stiffness: collagen gels, red blood cells (RBCs), and human fibroblasts, spanning a viscoelastic modulus range of five orders of magnitude. We show that AFMR can successfully quantify viscoelastic properties by probing many beads with high single-particle precision and reproducibility. Finally, we demonstrate that AFMR to map local sample heterogeneities as well as detect cellular responses to drugs.


Subject(s)
Elasticity , Erythrocytes , Fibroblasts , Rheology , Humans , Viscosity , Fibroblasts/physiology , Rheology/methods , Collagen/chemistry , Acoustics
2.
Eur Radiol ; 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38907886

ABSTRACT

OBJECTIVES: To assess 3-Tesla (3-T) ultra-small superparamagnetic iron oxide (USPIO)-enhanced MRI in detecting lymph node (LN) metastases for resectable adenocarcinomas of the pancreas, duodenum, or periampullary region in a node-to-node validation against histopathology. METHODS: Twenty-seven consecutive patients with a resectable pancreatic, duodenal, or periampullary adenocarcinoma were enrolled in this prospective single expert centre study. Ferumoxtran-10-enhanced 3-T MRI was performed pre-surgery. LNs found on MRI were scored for suspicion of metastasis by two expert radiologists using a dedicated scoring system. Node-to-node matching from in vivo MRI to histopathology was performed using a post-operative ex vivo 7-T MRI of the resection specimen. Sensitivity and specificity were calculated using crosstabs. RESULTS: Eighteen out of 27 patients (median age 65 years, 11 men) were included in the final analysis (pre-surgery withdrawal n = 4, not resected because of unexpected metastases peroperatively n = 2, and excluded because of inadequate contrast-agent uptake n = 3). On MRI 453 LNs with a median size of 4.0 mm were detected, of which 58 (13%) were classified as suspicious. At histopathology 385 LNs with a median size of 5.0 mm were found, of which 45 (12%) were metastatic. For 55 LNs node-to-node matching was possible. Analysis of these 55 matched LNs, resulted in a sensitivity and specificity of 83% (95% CI: 36-100%) and 92% (95% CI: 80-98%), respectively. CONCLUSION: USPIO-enhanced MRI is a promising technique to preoperatively detect and localise LN metastases in patients with pancreatic, duodenal, or periampullary adenocarcinoma. CLINICAL RELEVANCE STATEMENT: Detection of (distant) LN metastases with USPIO-enhanced MRI could be used to determine a personalised treatment strategy that could involve neoadjuvant or palliative chemotherapy, guided resection of distant LNs, or targeted radiotherapy. REGISTRATION: The study was registered on clinicaltrials.gov NCT04311047. https://clinicaltrials.gov/ct2/show/NCT04311047?term=lymph+node&cond=Pancreatic+Cancer&cntry=NL&draw=2&rank=1 . KEY POINTS: LN metastases of pancreatic, duodenal, or periampullary adenocarcinoma cannot be reliably detected with current imaging. This technique detected LN metastases with a sensitivity and specificity of 83% and 92%, respectively. MRI with ferumoxtran-10 is a promising technique to improve preoperative staging in these cancers.

3.
Nat Commun ; 15(1): 3456, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38658528

ABSTRACT

Intraflagellar transport (IFT) orchestrates entry of proteins into primary cilia. At the ciliary base, assembled IFT trains, driven by kinesin-2 motors, can transport cargo proteins into the cilium, across the crowded transition zone. How trains assemble at the base and how proteins associate with them is far from understood. Here, we use single-molecule imaging in the cilia of C. elegans chemosensory neurons to directly visualize the entry of kinesin-2 motors, kinesin-II and OSM-3, as well as anterograde cargo proteins, IFT dynein and tubulin. Single-particle tracking shows that IFT components associate with trains sequentially, both in time and space. Super-resolution maps of IFT components in wild-type and mutant worms reveal ciliary ultrastructure and show that kinesin-II is essential for axonemal organization. Finally, imaging cilia lacking kinesin-II and/or transition zone function uncovers the interplay of kinesin-II and OSM-3 in driving efficient transport of IFT trains across the transition zone.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Cilia , Kinesins , Caenorhabditis elegans/metabolism , Animals , Cilia/metabolism , Cilia/ultrastructure , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans Proteins/genetics , Kinesins/metabolism , Kinesins/genetics , Flagella/metabolism , Flagella/ultrastructure , Tubulin/metabolism , Axoneme/metabolism , Axoneme/ultrastructure , Dyneins/metabolism , Biological Transport , Single Molecule Imaging , Protein Transport
4.
Brain Spine ; 4: 102746, 2024.
Article in English | MEDLINE | ID: mdl-38510637

ABSTRACT

Introduction: Treatment-limiting decisions (TLDs) can be inevitable severe traumatic brain injury (s-TBI) patients, but data on their use remain scarce. Research question: To investigate the prevalence, timing and considerations of TLDs in s-TBI patients. Material and methods: s-TBI patients between 2008 and 2017 were analysed retrospecively. Patient data, timing, location, involvement of proxies, and reasons for TLDs were collected. Baseline characteristics and in-hospital outcomes were compared between s-TBI patients with and without TLDs. Results: TLDs were reported in 117 of 270 s-TBI patients (43.3%) and 95.9% of deaths after s-TBI were preceded by a TLD. The majority of TLDs (68.4%) were categorized as withdrawal of therapy, of which withdrawal of organ-support in 64.1%. Neurosurgical intervention was withheld in 29.9%. The median time from admission to TLD was 2 days [IQR, 0-8] and 50.4% of TLDs were made within 3 days of admission. The main reason for a TLD was that the patients were perceived as unsalvageable (66.7%). Nearly all decisions were made multidisciplinary (99.1%) with proxies involvement (75.2%). The predicted mortality (CRASH-score) between patients with and without TLDs were 72.6 vs. 70.6%. The percentage of TLDs in s-TBI patients increased from 20.0% in 2008 to 42.9% in 2012 and 64.3% in 2017. Discussion and conclusion: TLDs occurred in almost half of s-TBI patients and were instituted more frequently over time. Half of TLDs were made within 3 days of admission in spite of baseline prognosis between groups being similar. Future research should address whether prognostic nihilism contributes to self-fulfilling prophecies.

5.
Trials ; 25(1): 132, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368409

ABSTRACT

BACKGROUND: Nowadays, large benign lateral spreading lesions (LSLs) and sessile polyps in the colorectum are mostly resected by endoscopic mucosal resection (EMR). A major drawback of EMR is the polyp recurrence rate of up to 20%. Snare tip soft coagulation (STSC) is considered an effective technique to reduce recurrence rates. However, clinical trials on STSC have mainly been conducted in expert referral centers. In these studies, polyp recurrence was assessed optically, and additional adjunctive techniques were excluded. In the current trial, we will evaluate the efficacy and safety of STSC in daily practice, by allowing adjunctive techniques during EMR and the use of both optical and histological polyp recurrence to assess recurrences during follow-up. METHODS: The RESPECT study is a multicenter, parallel-group, international single blinded randomized controlled superiority trial performed in the Netherlands and Germany. A total of 306 patients undergoing piecemeal EMR for LSLs or sessile colorectal polyps sized 20-60 mm will be randomized during the procedure after endoscopic complete polyp resection to the intervention or control group. Post-EMR defects allocated to the intervention group will be treated with thermal ablation with STSC of the entire resection margin. Primary outcome will be polyp recurrence by optical and histological confirmation at the first surveillance colonoscopy after 6 months. Secondary outcomes include technical success and complication rates. DISCUSSION: The RESPECT study will evaluate if STSC is effective in reducing recurrence rates after piecemeal EMR of large colorectal lesions in daily clinical practice performed by expert and non-expert endoscopists. Moreover, endoscopists will be allowed to use adjunctive techniques to remove remaining adenomatous tissue during the procedure. Finally, adenomatous polyp recurrence during follow-up will be defined by histologic identification. TRIAL REGISTRATION: ClinicalTrials.gov NCT05121805. Registered on 16 November 2021. Start recruitment: 17 March 2022. Planned completion of recruitment: 31 April 2025.


Subject(s)
Adenoma , Colonic Polyps , Colorectal Neoplasms , Endoscopic Mucosal Resection , Humans , Endoscopic Mucosal Resection/adverse effects , Neoplasm Recurrence, Local/prevention & control , Colorectal Neoplasms/surgery , Colorectal Neoplasms/pathology , Adenoma/surgery , Adenoma/pathology , Colonoscopy/adverse effects , Colonoscopy/methods , Colonic Polyps/surgery , Treatment Outcome , Randomized Controlled Trials as Topic , Multicenter Studies as Topic
6.
Mater Today Bio ; 24: 100897, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38169974

ABSTRACT

In vitro cellular models denote a crucial part of drug discovery programs as they aid in identifying successful drug candidates based on their initial efficacy and potency. While tremendous headway has been achieved in improving 2D and 3D culture techniques, there is still a need for physiologically relevant systems that can mimic or alter cellular responses without the addition of external biochemical stimuli. A way forward to alter cellular responses is using physical cues, like 3D topographical inorganic substrates, to differentiate macrophage-like cells. Herein, protein secretion and gene expression markers for various macrophage subsets cultivated on a 3D topographical substrate are investigated. The results show that macrophages differentiate into anti-inflammatory M2-type macrophages, secreting increased IL-10 levels compared to the controls. Remarkably, these macrophage cells are differentiated into the M2d subset, making up the main component of tumour-associated macrophages (TAMs), as measured by upregulated Il-10 and Vegf mRNA. M2d subset differentiation is attributed to the topographical substrates with 3D fractal-like geometries arrayed over the surface, else primarily achieved by tumour-associated factors in vivo. From a broad perspective, this work paves the way for implementing 3D topographical inorganic surfaces for drug discovery programs, harnessing the advantages of in vitro assays without external stimulation and allowing the rapid characterisation of therapeutic modalities in physiologically relevant environments.

7.
J Forensic Sci ; 69(2): 651-658, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38037231

ABSTRACT

Establishing the path or trajectory of a fired bullet is an often recurring part of shooting incident reconstruction. The current study describes how gravitational pull causes a systemic error on the vertical component of a trajectory reconstruction. Bullet drop, drop angle, and vertical offset are explained and calculated for 10 different handgun/ammunition combinations over a range of distances up to 100 m. The presented results are intended to provide forensic firearm examiners with a reference frame for the magnitude of error introduced on handgun bullet trajectory reconstructions over distance. Threshold values of 20 and 30 m are proposed as conservative distances up to where bullet trajectories can be modeled as straight lines with subsonic/transonic handgun bullets and with supersonic handgun bullets respectively. Both the bullet drop and vertical offset will be below 5 cm at these distances for those categories. The drop angle will be below 0.3°.

8.
Gastroenterology ; 166(4): 690-703, 2024 04.
Article in English | MEDLINE | ID: mdl-38158089

ABSTRACT

BACKGROUND & AIMS: Gastrointestinal angiodysplasias are vascular anomalies that may result in transfusion-dependent anemia despite endoscopic therapy. An individual patient data meta-analysis of cohort studies suggests that octreotide decreases rebleeding rates, but component studies possessed a high risk of bias. We investigated the efficacy of octreotide in reducing the transfusion requirements of patients with angiodysplasia-related anemia in a clinical trial setting. METHODS: The study was designed as a multicenter, open-label, randomized controlled trial. Patients with angiodysplasia bleeding were required to have had at least 4 red blood cell (RBC) units or parental iron infusions, or both, in the year preceding randomization. Patients were allocated (1:1) to 40-mg octreotide long-acting release intramuscular every 28 days or standard of care, including endoscopic therapy. The treatment duration was 1 year. The primary outcome was the mean difference in the number of transfusion units (RBC + parental iron) between the octreotide and standard of care groups. Patients who received at least 1 octreotide injection or followed standard of care for at least 1 month were included in the intention-to-treat analyses. Analyses of covariance were used to adjust for baseline transfusion requirements and incomplete follow-up. RESULTS: We enrolled 62 patients (mean age, 72 years; 32 men) from 17 Dutch hospitals in the octreotide (n = 31) and standard of care (n = 31) groups. Patients required a mean number of 20.3 (standard deviation, 15.6) transfusion units and 2.4 (standard deviation, 2.0) endoscopic procedures in the year before enrollment. The total number of transfusions was lower with octreotide (11.0; 95% confidence interval [CI], 5.5-16.5) compared with standard of care (21.2; 95% CI, 15.7-26.7). Octreotide reduced the mean number of transfusion units by 10.2 (95% CI, 2.4-18.1; P = .012). Octreotide reduced the annual volume of endoscopic procedures by 0.9 (95% CI, 0.3-1.5). CONCLUSIONS: Octreotide effectively reduces transfusion requirements and the need for endoscopic therapy in patients with angiodysplasia-related anemia. CLINICALTRIALS: gov, NCT02384122.


Subject(s)
Anemia , Angiodysplasia , Colonic Diseases , Aged , Humans , Male , Anemia/drug therapy , Anemia/etiology , Angiodysplasia/complications , Angiodysplasia/diagnosis , Angiodysplasia/therapy , Colonic Diseases/drug therapy , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/drug therapy , Gastrointestinal Hemorrhage/etiology , Iron , Multicenter Studies as Topic , Octreotide/therapeutic use , Randomized Controlled Trials as Topic , Standard of Care , Female
9.
Ultrasound J ; 15(1): 46, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38063930

ABSTRACT

BACKGROUND: The goal is to estimate the additional value of ultrasonographic optic nerve sheath diameter (ONSD) measurement on days 1-3, on top of electroencephalography (EEG), pupillary light reflexes (PLR), and somatosensory evoked potentials (SSEP), for neurological outcome prediction of comatose cardiac arrest patients. We performed a prospective longitudinal cohort study in adult comatose patients after cardiac arrest. ONSD was measured on days 1-3 using ultrasound. Continuous EEG, PLR, and SSEP were acquired as standard care. Poor outcome was defined as cerebral performance categories 3-5 at 3-6 months. Logistic regression models were created for outcome prediction based on the established predictors with and without ONSD. Additional predictive value was assessed by increase in sensitivity for poor (at 100% specificity) and good outcome (at 90% specificity). RESULTS: We included 100 patients, 54 with poor outcome. Mean ONSD did not differ significantly between patients with good and poor outcome. Sensitivity for predicting poor outcome increased by adding ONSD to EEG and SSEP from 25% to 41% in all patients and from 27% to 50% after exclusion of patients with non-neurological death. CONCLUSIONS: ONSD on days 1-3 after cardiac arrest holds potential to add to neurological outcome prediction. TRIAL REGISTRATION: clinicaltrials.gov, NCT04084054. Registered 10 September 2019, https://www. CLINICALTRIALS: gov/study/NCT04084054 .

10.
Forensic Sci Int ; 353: 111858, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37863005

ABSTRACT

An automated approach for evaluating the strength of the evidence of firearm toolmark comparison results is presented for a common source scenario. First, comparison scores are derived describing the similarity of marks typically encountered on the primer of fired cartridge cases: aperture shear striations as well as breechface and firing pin impressions. Subsequently, these scores are interpreted using reference distributions of comparison scores obtained for representative known matching (KM) and known non-matching (KNM) ballistic samples in a common source, score-based likelihood ratio (LR) system. We study various alternatives to set up such an LR system and compare them using qualitative and quantitative criteria known from the literature. As an example, results are applied to establish a system suitable for a firearm-ammunition combination often encountered in casework: Glock firearms with Fiocchi nickel primer ammunition. The system outputs an LR and a measure of LR uncertainty. The range of possible LR-values is limited to a minimum and maximum value in areas of the score domain with little reference data. Finally, the feasibility of combining LRs of different mark types into one LR for the entire primer is assessed. For the distribution models considered in this paper, different modeling approaches are optimal for different types of similarity scores. For the chosen firearm-ammunition combination, non-parametric Kernel Density Estimation (KDE) models perform best for similarity scores based on the correlation coefficient, whereas parametric models perform best for the Congruent Matching Cells (CMC) scores, assuming binomial and beta-binomial models for KM and KNM score distributions respectively. Finally, it is demonstrated that individual LRs of different mark types can be combined into one LR, to interpret a set of different marks on the primer as a whole.

11.
Nurs Crit Care ; 28(6): 1159-1169, 2023 11.
Article in English | MEDLINE | ID: mdl-37902980

ABSTRACT

BACKGROUND: The negative impact on long-term health-related outcomes among relatives of critically ill patients in the intensive care unit (ICU) has been well described. High-quality ICU specialized follow-up care, which is easily accessible with digital innovation and which is designed by and with relevant stakeholders (i.e., ICU patients' relatives and nurses), should be considered to reduce these impairments in the psychological and social domains. AIM: The programme's aim is to develop and test an e-health intervention in a follow-up service to support ICU patients' relatives. Here, the protocol for the overall study programme will be described. STUDY DESIGN: The overall study comprises a mixed-methods, multicentre research design with qualitative and quantitative study parts. The study population is ICU patients' adult relatives and ICU nurses. The main outcomes are the experiences of these stakeholders with the newly developed e-health intervention. There will be no predefined selection based on age, gender, and level of education to maximize diversity throughout the study programme. After the participants provide informed consent, data will be gathered through focus groups (n = 5) among relatives and individual interviews (n = 20) among nurses exploring the needs and priorities of a digital follow-up service. The findings will be explored further for priority considerations among members of the patient/relative organization (aiming n = 150), which will serve as a basis for digital prototypes of the e-health intervention. Assessment of the intervention will be followed during an iterative process with investigator-developed questionnaires. Finally, symptoms of anxiety and depression will be measured with the 14-item Dutch version of the 'Hospital Anxiety and Depression Scale', and symptoms of posttraumatic stress will be measured with the 21-item Dutch version of the 'Impact of Events Scale-Revised' to indicate the effectiveness of digital support among ICU patients' relatives. RELEVANCE TO CLINICAL PRACTICE: The e-health intervention to be developed during this research programme can possibly bridge the gap in integrated ICU follow-up care by providing relevant information, self-monitoring and stimulating self-care among ICU patients' relatives.


Subject(s)
Critical Care , Telemedicine , Adult , Humans , Follow-Up Studies , Critical Care/psychology , Intensive Care Units , Survivors
12.
Diagnostics (Basel) ; 13(20)2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37892019

ABSTRACT

The preoperative prediction of resectability pancreatic ductal adenocarcinoma (PDAC) is challenging. This retrospective single-center study examined tumor and vessel radiomics to predict the resectability of PDAC in chemo-naïve patients. The tumor and adjacent arteries and veins were segmented in the portal-venous phase of contrast-enhanced CT scans, and radiomic features were extracted. Features were selected via stability and collinearity testing, and least absolute shrinkage and selection operator application (LASSO). Three models, using tumor features, vessel features, and a combination of both, were trained with the training set (N = 86) to predict resectability. The results were validated with the test set (N = 15) and compared to the multidisciplinary team's (MDT) performance. The vessel-features-only model performed best, with an AUC of 0.92 and sensitivity and specificity of 97% and 73%, respectively. Test set validation showed a sensitivity and specificity of 100% and 88%, respectively. The combined model was as good as the vessel model (AUC = 0.91), whereas the tumor model showed poor performance (AUC = 0.76). The MDT's prediction reached a sensitivity and specificity of 97% and 84% for the training set and 88% and 100% for the test set, respectively. Our clinician-independent vessel-based radiomics model can aid in predicting resectability and shows performance comparable to that of the MDT. With these encouraging results, improved, automated, and generalizable models can be developed that reduce workload and can be applied in non-expert hospitals.

13.
Br J Surg ; 110(12): 1877-1882, 2023 11 09.
Article in English | MEDLINE | ID: mdl-37811814

ABSTRACT

BACKGROUND: Cholecystectomy in patients with idiopathic acute pancreatitis (IAP) is controversial. A randomized trial found cholecystectomy to reduce the recurrence rate of IAP but did not include preoperative endoscopic ultrasonography (EUS). As EUS is effective in detecting gallstone disease, cholecystectomy may be indicated only in patients with gallstone disease. This study aimed to determine the diagnostic value of EUS in patients with IAP, and the rate of recurrent pancreatitis in patients in whom EUS could not determine the aetiology (EUS-negative IAP). METHODS: This prospective multicentre cohort study included patients with a first episode of IAP who underwent outpatient EUS. The primary outcome was detection of aetiology by EUS. Secondary outcomes included adverse events after EUS, recurrence of pancreatitis, and quality of life during 1-year follow-up. RESULTS: After screening 957 consecutive patients with acute pancreatitis from 24 centres, 105 patients with IAP were included and underwent EUS. In 34 patients (32 per cent), EUS detected an aetiology: (micro)lithiasis and biliary sludge (23.8 per cent), chronic pancreatitis (6.7 per cent), and neoplasms (2.9 per cent); 2 of the latter patients underwent pancreatoduodenectomy. During 1-year follow-up, the pancreatitis recurrence rate was 17 per cent (12 of 71) among patients with EUS-negative IAP versus 6 per cent (2 of 34) among those with positive EUS. Recurrent pancreatitis was associated with poorer quality of life. CONCLUSION: EUS detected an aetiology in a one-third of patients with a first episode of IAP, requiring mostly cholecystectomy or pancreatoduodenectomy. The role of cholecystectomy in patients with EUS-negative IAP remains uncertain and warrants further study.


Some patients develop acute inflammation of the pancreas without a clear cause. These patients have a high risk of developing more episodes of acute inflammation of the pancreas. Potentially, such inflammation could be caused by tiny gallstones that physicians are not able to detect. If this is true, these patients may also benefit from surgical removal of the gallbladder. However, this is still controversial. Endoscopic ultrasonography is a diagnostic procedure during which a physician looks at the gallbladder and bile ducts in detail via a small ultrasound probe inserted through the mouth. This endoscopic ultrasonography may be able to detect gallstones better than physicians were able to previously. This study tested the value of endoscopic ultrasonography, and the number of patients who developed more episodes of acute inflammation after endoscopic ultrasonography was recorded. Some 106 patients with acute inflammation of the pancreas for the first time without a clear cause participated and were offered endoscopic ultrasonography. The number of times endoscopic ultrasonography found a cause for the acute inflammation was recorded, as well as safety parameters, number of patients who developed more episodes of acute inflammation, and quality of life. After screening 957 patients, 105 ultimately underwent endoscopic ultrasonography. A cause was found in one-third of patients. This was mostly (tiny) gallstones, but chronic inflammation and even tumours were found. These patients were mostly treated surgically for their gallstones and tumours. In the first year after the first acute episode of inflammation, the inflammation came back at least once in almost one in six patients in whom endoscopic ultrasonography did not find a cause. This occurred less in patients in whom a cause was found; the inflammation came back in 1 in 16 of these patients. It was also found that having inflammation coming back negatively affected quality of life. In this study, endoscopic ultrasonography was able to detect a cause in one-third of patients with first-time acute inflammation of the pancreas. In one in four patients, this cause could be treated by a surgical procedure. Whether surgical removal of the gallbladder can be helpful in patients in whom endoscopic ultrasonography is not able to detect an aetiology should be investigated in further studies.


Subject(s)
Cholelithiasis , Pancreatitis, Chronic , Humans , Endosonography , Acute Disease , Prospective Studies , Cohort Studies , Quality of Life
14.
Molecules ; 28(17)2023 Aug 22.
Article in English | MEDLINE | ID: mdl-37687009

ABSTRACT

1,4-Oxathiins are valued for a breadth of bioactivities and are known commercial fungicides. This article explores a novel preparation of 2,3,6-trisubstituted 1,4-oxathiin-S,S-dioxides via the reaction of benzyl 1-alkynyl sulfones and aryl aldehydes under basic conditions. A total of 20 examples possessing exclusively a trans arrangement of the 2,3-diaryl substituents are exhibited; the products demonstrate a variation of functional groups on the aryl ring attached to the heterocyclic ring system. The preparation is hindered by the base sensitivity of the products, and a ring-opened by-product typically contaminates the reaction mixture. A DFT assessment of the overall system includes a lithium counterion and offers possible pathways for the incorporation of the aldehyde, the cyclization step and the requisite proton transfers. In addition, the DFT work reveals options for the ring opening chemistry. It appears the trans 2,3-diaryl selectivity is set during the cyclization stage of the reaction sequence. The practical work uncovers a new reaction pathway to create a family of novel 1,4-oxathiin-S,S-dioxides whereas the computational work offers an understanding of the structures and possible mechanisms involved.

15.
Theor Med Bioeth ; 44(4): 341-351, 2023 08.
Article in English | MEDLINE | ID: mdl-37606813

ABSTRACT

In a thought-provoking article - or how she herself named it, 'a thought experiment' - the philosopher-medical ethicist Anna Smajdor analyzed in this journal the idea of whole-body gestational donation (WBGD) in brain-dead female patients, as an alternative means of gestation for prospective women who cannot or prefer not to become pregnant themselves. We have serious legal, economical, medical and ethical concerns about this proposal. First, consent for eight months of ICU treatment can never be assumed to be derived from consent for post-mortem organ donation; these two are of an incomparable and entirely different medical and ethical order. Moreover, the brain-dead woman is very likely to be medically unfit for high-tech surrogacy and the brain-dead state poses a high risk for deficient embryo/fetal development. Second, from a scarcity perspective, occupying an ICU bed for eight months appears to be unjust. The costs for eight months of ICU treatment are far too high compared to the costs of surrogacy for a living, selected, and healthy woman. Neither insurance companies nor prospective parents will want to pay these exceptionally high costs for a dead woman if a living surrogate mother can be hired for a considerably lower amount. Third, there is an increased risk for harm of the child to be in WBGD. And finally, WBGD risks violating the brain-dead woman's dignity and harming the interests of her loved ones. In short, there is simply no need for brain-dead women as surrogates.


Subject(s)
Brain Death , Health Status , Female , Child , Pregnancy , Humans , Prospective Studies , Parents
16.
Neoplasia ; 43: 100924, 2023 09.
Article in English | MEDLINE | ID: mdl-37562257

ABSTRACT

Cutaneous melanoma is the deadliest form of skin neoplasm and its high mortality rates could be averted by early accurate detection. While the detection of melanoma is currently reliant upon melanin visualisation, research into melanosome biogenesis, as a key driver of pathogenesis, has not yielded technology that can reliably distinguish between atypical benign, amelanotic and melanotic lesions. The endosomal-lysosomal system has important regulatory roles in cancer cell biology, including a specific functional role in melanosome biogenesis. Herein, the involvement of the endosomal-lysosomal system in melanoma was examined by pooled secondary analysis of existing gene expression datasets. A set of differentially expressed endosomal-lysosomal genes was identified in melanoma, which were interconnected by biological function. To illustrate the protein expression of the dysregulated genes, immunohistochemistry was performed on samples from patients with cutaneous melanoma to reveal candidate markers. This study demonstrated the dysregulation of Syntenin-1, Sortilin and Rab25 may provide a differentiating feature between cutaneous melanoma and squamous cell carcinoma, while IGF2R may indicate malignant propensity in these skin cancers.


Subject(s)
Carcinoma, Squamous Cell , Melanoma , Skin Neoplasms , Humans , Melanoma/pathology , Skin Neoplasms/pathology , Carcinoma, Squamous Cell/pathology , Lysosomes/genetics , Lysosomes/pathology , rab GTP-Binding Proteins , Melanoma, Cutaneous Malignant
17.
World J Clin Oncol ; 14(4): 179-189, 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37124133

ABSTRACT

BACKGROUND: Extramedullary multiple myeloma (MM) (EMM) is a rare and aggressive subentity of MM that can be present at diagnosis or develop anytime during the disease course. There is a paucity of data on the clinical characteristics and overall epidemiology of EMM. Furthermore, there is a scarcity of data on how the interaction of age and gender influences the survival of EMM. AIM: To evaluate the clinical characteristics of patients with EMM over the past 2 decades and to identify epidemiologic characteristics that may impact overall prognosis. METHODS: A total of 858 patients diagnosed with EMM, between 2000 and 2017, were ultimately enrolled in our study by retrieving the Surveillance, Epidemiology, and End Results database. We analyzed demographics, clinical characteristics, and overall mortality (OM) as well as cancer-specific mortality (CSM) of EMM. Variables with a P value < 0.1 in the univariate Cox regression were incorporated into the multivariate Cox model to determine the independent prognostic factors, with a hazard ratio (HR) of greater than 1 representing adverse prognostic factors. RESULTS: From a sample of 858 EMM, the male gender (63.25%), age range 60-79 years (51.05%), and non-Hispanic whites (66.78%) were the most represented. Central Nervous System and the vertebral column was the most affected site (33.10%). Crude analysis revealed higher OM in the age group 80+ [HR = 6.951, 95% confidence interval (95%CI): 3.299-14.647, P = 0], Non-Hispanic Black population (HR = 1.339, 95%CI: 1.02-1.759, P = 0.036), Bones not otherwise specified (NOS) (HR = 1.74, 95%CI: 1.043-2.902, P = 0.034), and widowed individuals (HR = 2.107, 95%CI: 1.511-2.938, P = 0). Skin involvement (HR = 0.241, 95%CI: 0.06-0.974, P = 0.046) and a yearly income of $75000+ (HR = 0.259, 95%CI: 0.125-0.538, P = 0) had the lowest OM in the crude analysis. Crude analysis revealed higher CSM in the age group 80+, Non-Hispanic Black, Bones NOS, and widowed. Multivariate cox proportional hazard regression analyses only revealed higher OM in the age group 80+ (HR = 9.792, 95%CI: 4.403-21.774, P = 0) and widowed individuals (HR = 1.609, 95%CI: 1.101-2.35, P = 0.014). Multivariate cox proportional hazard regression analyses of CSM also revealed higher mortality of the same groups. Eyes, mouth, and ENT involvement had the lowest CSM in the multivariate analysis. There was no interaction between age and gender in the adjusted analysis for OM and CSM. CONCLUSION: EMM is a rare entity. To our knowledge, there is a scarcity of data on the clinical characteristics and prognosis factors of patients with extramedullary multiple myeloma. In this retrospective cohort, using a United States-based population, we found that age, marital status, and tumor site were independent prognostic factors. Furthermore, we found that age and gender did not interact to influence the mortality of patients with EMM.

18.
Nucleic Acids Res ; 51(13): 6540-6553, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37254785

ABSTRACT

Bacteriophage T7 single-stranded DNA-binding protein (gp2.5) binds to and protects transiently exposed regions of single-stranded DNA (ssDNA) while dynamically interacting with other proteins of the replication complex. We directly visualize fluorescently labelled T7 gp2.5 binding to ssDNA at the single-molecule level. Upon binding, T7 gp2.5 reduces the contour length of ssDNA by stacking nucleotides in a force-dependent manner, suggesting T7 gp2.5 suppresses the formation of secondary structure. Next, we investigate the binding dynamics of T7 gp2.5 and a deletion mutant lacking 21 C-terminal residues (gp2.5-Δ21C) under various template tensions. Our results show that the base sequence of the DNA molecule, ssDNA conformation induced by template tension, and the acidic terminal domain from T7 gp2.5 significantly impact on the DNA binding parameters of T7 gp2.5. Moreover, we uncover a unique template-catalyzed recycling behaviour of T7 gp2.5, resulting in an apparent cooperative binding to ssDNA, facilitating efficient spatial redistribution of T7 gp2.5 during the synthesis of successive Okazaki fragments. Overall, our findings reveal an efficient binding mechanism that prevents the formation of secondary structures by enabling T7 gp2.5 to rapidly rebind to nearby exposed ssDNA regions, during lagging strand DNA synthesis.


Subject(s)
Bacteriophage T7 , Viral Proteins , Bacteriophage T7/genetics , DNA/metabolism , DNA Replication , DNA, Single-Stranded/genetics , DNA, Single-Stranded/metabolism , Molecular Conformation , Viral Proteins/metabolism
19.
Opt Lett ; 48(10): 2615-2618, 2023 May 15.
Article in English | MEDLINE | ID: mdl-37186722

ABSTRACT

Fiber-optic hydrophones (FOHs) are widely used to detect high-intensity focused ultrasound (HIFU) fields. The most common type consists of an uncoated single-mode fiber with a perpendicularly cleaved end face. The main disadvantage of these hydrophones is their low signal-to-noise ratio (SNR). To increase the SNR, signal averaging is performed, but the associated increased acquisition times hinder ultrasound field scans. In this study, with a view to increasing SNR while withstanding HIFU pressures, the bare FOH paradigm is extended to include a partially reflective coating on the fiber end face. Here, a numerical model based on the general transfer-matrix method was implemented. Based on the simulation results, a single-layer, 172 nm TiO2-coated FOH was fabricated. The frequency range of the hydrophone was verified from 1 to 30 MHz. The SNR of the acoustic measurement with the coated sensor was 21 dB higher than that of the uncoated one. The coated sensor successfully withstood a peak positive pressure of 35 MPa for 6000 pulses.

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