Thrombosis of the Vein of Trolard: An Atypical Presentation of Protein C Deficiency

Cerebral venous thrombosis refers to complete or partial occlusion of the cerebral sinus/es or the feeding cortical veins, resulting in secondary effects of vascular congestion and focal or generalized neurological deficits. One of the important causes of venous thromboembolism is inherited thrombophilia. Our case is of a 34-year-old male with no previous comorbidity who presented to the emergency department with complaints of sudden onset left-sided weakness, seizures, and loss of consciousness for one day. Thrombosis of the vein of Trolard was diagnosed based on magnetic resonance venography (MRV) film. His MRI with MRV revealed an attenuated caliber of the vein of Trolard along with abnormal signal intensity in the right fronto-parietal region and the right falcine location. He was managed with intravenous medication, including levetiracetam and topiramate. Once the diagnosis was established, he was commenced on subcutaneous Enoxaparin. Consequently, his GCS improved from 6/15 to 15/15 within the first 24 hours, and he could move his limbs on the day of discharge without any significant disability.

Measurements of Groomed-Jet Substructure of Charm Jets Tagged by D^{0} Mesons in Proton-Proton Collisions at sqrt[s]=13 TeV

Understanding the role of parton mass and Casimir color factors in the quantum chromodynamics parton shower represents an important step in characterizing the emission properties of heavy quarks. Recent experimental advances in jet substructure techniques have provided the opportunity to isolate and characterize gluon emissions from heavy quarks. In this Letter, the first direct experimental constraint on the charm-quark splitting function is presented, obtained via the measurement of the groomed shared momentum fraction of the first splitting in charm jets, tagged by a reconstructed D^{0} meson. The measurement is made in proton-proton collisions at sqrt[s]=13  TeV, in the low jet transverse-momentum interval of 15≤p_{T}^{jet ch}<30  GeV/c where the emission properties are sensitive to parton mass effects. In addition, the opening angle of the first perturbative emission of the charm quark, as well as the number of perturbative emissions it undergoes, is reported. Comparisons to measurements of an inclusive-jet sample show a steeper splitting function for charm quarks compared with gluons and light quarks. Charm quarks also undergo fewer perturbative emissions in the parton shower, with a reduced probability of large-angle emissions.

Outcome of conventional radiotherapy in small centrally located tumours or lymph nodes: minimal toxicity, remarkable survival but challenging loco-regional control

BACKGROUND

In peripheral lung tumours, stereotactic body radiotherapy (SBRT) is superior to conventional RT. SBRT has also shown high loco-regional control (LC) in centrally located tumours, but there is a high risk of severe toxicity. The STRICTSTARLung trial (NCT05354596) examines if risk-adapted SBRT for central tumours is feasible. In this study, we examined overall survival (OS), Disease-free survival (DSF), LC, and toxicity in patients with central tumours that could have been candidates for SBRT but received conventional RT.

MATERIAL AND METHODS

Retrospectively, we evaluated 49 lung cancer patients that between 2008 and 2021 received RT (60-70Gy in 2 Gy fractions) for a solitary tumour or lymph node with a diameter <5cm located <2cm from the bronchial tree, oesophagus, aorta or heart. All tumours were pathologically verified; 30 were primary lung tumours (T1b-T4) and 19 were solitary lymph nodes (T0N1-N2). Chemotherapy was administered as concomitant (29) or sequential (4). OS and LC were analysed using Kaplan Meier. Cox proportional hazards model for OS and disease-free survival (DFS) was performed including tumour volume, histology, sex, T- vs N-site and chemotherapy. Toxicity was scored.

RESULTS

In 42 patients, the tumour was located <1 cm to mediastinum. Median follow-up time was 44 months (range: 7-123). The median OS was 51 months. OS at 1-, 3- and 5-year was 88% (SE:5), 59% (SE:7) and 50% (SE:8). Loco-regional recurrences occurred in 16 patients resulting in 1-, and 3-year LC rates of 77% (SE:6) and 64% (SE:8). The majority occurred within 3 years after RT. Only stage showed significant impact on OS and DFS. No patients experienced grade 4-5 toxicity. Seven patients developed grade 3 toxicity (5 oesophageal stenosis, 2 pneumonitis).

CONCLUSION

Conventional RT for patients with small central lung tumours or solitary lymph nodes is feasible. Median OS was 51 months, and toxicity was low with no grade 4-5 events.

The Representation of Surgery in Oncology Clinical Trials: 2001 to 2022

BACKGROUND

Surgery is a mainstay of cancer care. Since the advancement of cancer treatment occurs through clinical trials, it is critical to investigate the degree and nature of representation of surgery in oncological clinical trials.

METHODS

This observational analysis used publicly available data from clinicaltrials.gov to investigate non-industry-funded oncological clinical trials in the United States between 2012 and 2022.

RESULTS

From 2012 to 2022, 1,861 (15.7%) of the 11,843 registered oncologic clinical trials were surgical. There was a 43.2% increase in proportional surgical trials and an 18.9% increase in oncology trials over the last two decades. Surgery+diagnostic-technique trials increased from 5.14 to 12.6% (P < 0.001, 95%CI [- 0.097, - 0.052]), surgery+radiation trials increased from 5.24 to 8.1% (P = 0.004, 95%CI [- 0.047, - 0.0088]), surgery+systemic-therapy trials decreased from 34.5 to 29.2% (P = 0.003, 95%CI [0.018, 0.088]), surgery+supportive-therapy trials increased from 8.0 to 11.3% (P = 0.004, 95%CI [- 0.056, - 0.01]) and 'surgery-as-the-variable' trials decreased from 12.0 to 3.5% (P < 0.001, 95%CI[0.065, 0.1]). Systemic therapy with biologics increased from 38.1 to 53.9% (P < 0.001, 95%CI [- 0.22, - 0.091]). Surgery-vs.-no-surgery trials increased from 16.8 to 37.3% (P = 0.001, 95%CI [- 0.32, - 0.078]).

CONCLUSION

Surgical oncology trials increased by 43.2% over the last 10 years. The focus of clinical trials is changing to the encouragement of innovation in more diagnostic and less invasive techniques, and targeted therapies.

Temporal Structures in Positron Spectra and Charge-Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4×10^{6} positrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5σ at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5σ for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere.

Dosimetric Accuracy of Multi-Target Biology-Guided Radiotherapy Treatments in a Single Session

PURPOSE/OBJECTIVE(S)

We present the first dosimetric measurements of single session, multi-target BgRT deliveries using a clinically realistic motion phantom on a research-only version of the RefleXion X1 system.

MATERIALS/METHODS

A custom-made anthropomorphic phantom of a human torso with embedded fillable targets mimicking 18F-FDG-avid lesions was used. From the three embedded spherical targets, Target 1 was 26 mm in diameter coupled with a 3D independent respiratory motion with 22 mm range, whereas Target 2 and 3 were 22 mm in diameter and moved with a 1D 5 mm maximum sinusoidal motion. The 18F-FDG concentration in the background cavity of the phantom was 5 kBq/ml, and the targets were loaded with 10:1, 8:1 and 6:1 contrast relative to the background for Targets 1, 2, 3, respectively. Spherical structures were contoured as GTVs (CTV = GTV) and a 5 mm margin was added to create PTVs. Motion extent of the tumors were captured to create biological tracking zones for each target. Treatment plans were generated using a research version of the Reflexion treatment planning software to deliver 8 Gy/fx to the PTVs. The treatment delivery was repeated 2 times, and each time the phantom was refilled according to the plan. PET image evaluation metrics for each of the three targets were also recorded. Target dosimetry was measured using a combination of radiographic film and ion chamber. The maximum distance between the 97% prescription isodose line from the plan and the film measurements was used to characterize the dosimetric accuracy of the tracked deliveries. CTV and PTV min, max, and mean doses measured on film were also recorded for each target.

RESULTS

Treatment plans were successfully created with 100% prescription dose coverage to each target loaded with different FDG ratios. Total treatment times for the single-plan, three-target deliveries were less than 80 minutes. PET evaluation metrics at imaging-only and pre-scan, and planning and film dosimetry to the GTV and PTV for each of the three targets is shown in table below (mean ± standard deviation of both deliveries). The CTV dose coverage was maintained for all targets. The shrinkage distance of the 97% prescription dose isodose line on the film plane for all three targets was less than 3 mm for both tests, and ranged from -0.4 to -2.34 mm.

CONCLUSION

These results demonstrate that high tracking accuracy and dosimetric accuracy can be achieved in single session, multi-target deliveries over a range of target-to-background 18F-FDG concentrations and target motion patterns.

A Multicenter Study of Clinician and Patient Reported Acute and Late Toxicity after Radical (Chemo)Radiotherapy for Non-Endemic Nasopharyngeal Cancer

PURPOSE/OBJECTIVE(S)

Curative (chemo)radiotherapy ((CT)RT) for Nasopharyngeal cancers (NPC) achieves excellent disease control but is associated with significant late toxicities despite modern treatment delivery. Contemporary late toxicity data, including patient reported outcomes (PROs), is limited in the non-endemic population; we present a large contemporary series of toxicity outcomes and late PROs following treatment of non-endemic NPC.

MATERIALS/METHODS

Adult patients completing radical (CT)RT for primary NPC between February 2016 and 2020 at 7 large UK cancer centers were identified on institutional databases. Patients were excluded if they had prior head and neck cancer or prior therapeutic head and neck surgery (except neck dissection). Patients with an active other cancer were excluded from PRO assessment. Demographic, treatment, acute toxicity and outcome data were collected retrospectively from patient records. Disease-free patients were invited to complete an M.D. Anderson Dysphagia Index (MDADI) and University of Washington (UoW) Quality of Life (QoL) PROs questionnaires.

RESULTS

A total of 180 eligible patients were identified: 68% male, median age 54 years, 11% ≥70 years. EBV status was positive in 61% (unknown 12%). Patients had stage I (5%), II (22%), III (37%), IV (36%) disease; 95% were performance status ≤1 at baseline. Median follow-up was 31.2 months (range 0-68). A total of 54% received 70Gy in 33-35# and 43% received 65-66 Gy in 30-33#. 66% received induction and 65% received concurrent chemotherapy. 9.5% had residual disease at the first follow-up scan. Subsequent locoregional or distant recurrence occurred in 5% and 12% respectively. At last assessment, 84% patients were alive, 16% had died (of which 70% had active disease). Acute treatment toxicity included: 63% of patients required enteral support (median duration 98 days) with 9% a feeding tube at 1 year post treatment. 18% G3 dermatitis, 53% G3 mucositis. 82% requiring opioids and 40% admitted for symptom management. 90 patients completed the PROs (76% response rate) at a median of 37.8 months post treatment (Table 1). These demonstrate significant QoL detriment: 28% report significant pain, 24% require regular analgesia, and 59% report significant impact on daily activity. This was found to persist at different timepoints (not shown).

CONCLUSION

Excellent cancer survival outcomes are seen in a non-selected, non-endemic NPC population. However significant acute and late toxicity following radical treatment is identified which can profoundly negatively impact QoL in a relatively young cohort. This highlights the importance of ongoing efforts to reduce toxicity and supports the prospective evaluation of potential toxicity sparing technologies, such as proton beam radiotherapy.

Characterization of Biology-Guided Radiotherapy Accuracy as a Function of PET Tracer Uptake

PURPOSE/OBJECTIVE(S)

To characterize the tracking capability and dosimetric accuracy of biology-guided radiotherapy (BgRT) under clinically relevant PET tracer uptake scenarios relative to the background.

MATERIALS/METHODS

A custom-made anthropomorphic phantom filled with a liquid 18F-FDG solution including two embedded fillable 22 mm diameter spherical structures mimicking GTV (= CTV) and OAR was coupled to motion stages to create an independent 3D respiratory motion with 22 mm maximum range for target and a 5 mm 1D sinusoidal motion in the OAR. The biology-tracking zone (BTZ) was generated by adding 5 mm margin to the motion extent. The three BgRT scenarios studied were representative of tumors with good (8:1), borderline (4:1) and undesired (2:1) PET biodistributions compared to background. The clinical safety limit of BgRT uses Activity Concentration within the BTZ (AC ≥ 5 kBq/ml) and Normalized Target Signal as a contrast metric (NTS ≧ 2.7 for planning and ≧ 2 for delivery). The BgRT deliveries were repeated 3 times with radiochromic film and integrated ion chamber capturing the target and OAR doses. Tracked dosimetry was assessed using a margin-loss calculation defined as the maximum linear difference in distance between the planned and delivered 97% prescription iso-dose lines.

RESULTS

The imaging-only PET images used to create BgRT plans had an AC of 7.0, 5.3, and 1.6 kBq/ml with an NTS of 6.8, 5.3, and 1.8 for 8:1, 4:1, and 2:1 concentrations, respectively. Qualitatively, the target was not visible on the planning PET images 2:1 loading scenario. At delivery, the mean pre-scan activity concentrations were 6.8, 4.7, and 3.7 kBq/ml with corresponding mean NTS of 3.7, 2.6, 1.5 for 8:1, 4:1 and 2:1 deliveries. The pre-scan values of AC or NTS did not satisfy the clinical system safety limits for 4:1 and 2:1 ratio experiments, but the engineering software allowed for the delivery to capture the resulting doses. The deliveries showed a prescription dose coverage to the CTV of 100% for the 8:1 and 4:1 cases, but 88% for the 2:1 case. When compared to the planned dose values, the delivered minimum doses were -7.6%, -8.6% and -10.9%, whereas the maximum dose differences in CTV were 1.2%, 0% and -4.8% of the planned dose distributions of the 8:1, 4:1 and 2:1 cases, respectively. Calculated margin losses were -2.3, -3.8, and -5.5 mm, for the 8:1, 4:1, and 2:1 cases, respectively. The maximum OAR doses were less than the maximum doses predicted on the bounded DVH curves for all scenarios.

CONCLUSION

With sufficient tracer uptake in the target, BgRT can deliver tracked dosimetry for targets with a large respiratory motion profile. Both the good BgRT candidate and borderline cases produced clinically acceptable delivered doses, even though the borderline case was flagged by the clinical system safety checks. As expected, the delivered BgRT dose distributions were suboptimal with reduced tumor over background PET contrast.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)]  ps and B_{Λ}=[102±63(stat)±67(syst)]  keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

Biomedical instrumentation of photoacoustic imaging and quantitative sensing for clinical applications

Photoacoustic (PA) imaging has been well researched over the last couple of decades and has found many applications in biomedical engineering. This has evinced interest among many scientists in developing this as a compact instrument for biomedical diagnosis. This review discusses various instrumentation developments for PA experimental setups and their applications in the biomedical diagnostic field. It also covers the PA spectral response or PA sensing technique, which uses the spectral information of the PA signal and performs sensing to deliver a fast, cost-effective, and compact screening tool instead of imaging. Primarily, this review provides an overview of PA imaging concepts and the development of hardware instrumentation systems in both the excitation and acquisition stages of this technique. Later, the paper discusses PA sensing, the quantitative spectral parameter extraction from the PA spectrum, and the correlation study of the spectral parameters with the physical parameters of the tissue. This PA sensing technique was used to diagnose various diseases, such as thyroid nodules, breast cancer, renal disorders, and zoonotic diseases, based on the mechanical and biological characteristics of the tissues. The paper culminates with a discussion section that provides future developments that are necessary to take this technique into clinical applications as a quantitative PA imaging technique.

Functional outcomes after transanal ileal pouch-anal anastomosis for ulcerative colitis: narrative review of the current literature

The transanal approach to ileal pouch-anal anastomosis (Ta-IPAA) for ulcerative colitis was introduced in 2015 and has since been shown to be a safe and feasible technique, although the impact of this approach on patient function remains unclear. A systematic literature review was performed to identify studies exploring functional outcomes and quality of life after Ta-IPAA. Seven papers were identified, which all demonstrated satisfactory functional outcomes after Ta-IPAA as measured by tools such as Cleveland Global Quality of Life (CGQOL), Oresland Score (OS), Pouch Functional Score (PFS), and Inflammatory Bowel Disease Questionnaire (IBDQ). Many gaps in the literature were identified including paucity of follow-up data beyond the 1-year mark, lack of fertility and fecundity assessment as functional outcomes, and limited evaluation of objective physiologic anal sphincter function. The Ta-IPAA therefore shows promise for good functional results in the short-term, although further research will be required to evaluate the stability of function over time as the technique becomes increasingly integrated into modern surgical practice.

Contribution of local regeneration of glucocorticoids to tissue steroid pools

11β-Hydroxysteroid dehydrogenase 1 (11βHSD1) is a drug target to attenuate adverse effects of chronic glucocorticoid excess. It catalyses intracellular regeneration of active glucocorticoids in tissues including brain, liver and adipose tissue (coupled to hexose-6-phosphate dehydrogenase, H6PDH). 11βHSD1 activity in individual tissues is thought to contribute significantly to glucocorticoid levels at those sites, but its local contribution vs glucocorticoid delivery via the circulation is unknown. Here, we hypothesised that hepatic 11βHSD1 would contribute significantly to the circulating pool. This was studied in mice with Cre-mediated disruption of Hsd11b1 in liver (Alac-Cre) vs adipose tissue (aP2-Cre) or whole-body disruption of H6pdh. Regeneration of [9,12,12-2H3]-cortisol (d3F) from [9,12,12-2H3]-cortisone (d3E), measuring 11βHSD1 reductase activity was assessed at steady state following infusion of [9,11,12,12-2H4]-cortisol (d4F) in male mice. Concentrations of steroids in plasma and amounts in liver, adipose tissue and brain were measured using mass spectrometry interfaced with matrix-assisted laser desorption ionisation or liquid chromatography. Amounts of d3F were higher in liver, compared with brain and adipose tissue. Rates of appearance of d3F were ~6-fold slower in H6pdh-/- mice, showing the importance for whole-body 11βHSD1 reductase activity. Disruption of liver 11βHSD1 reduced the amounts of d3F in liver (by ~36%), without changes elsewhere. In contrast disruption of 11βHSD1 in adipose tissue reduced rates of appearance of circulating d3F (by ~67%) and also reduced regenerated of d3F in liver and brain (both by ~30%). Thus, the contribution of hepatic 11βHSD1 to circulating glucocorticoid levels and amounts in other tissues is less than that of adipose tissue.

Measurement of the J/ψ Polarization with Respect to the Event Plane in Pb-Pb Collisions at the LHC

We study the polarization of inclusive J/ψ produced in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC in the dimuon channel, via the measurement of the angular distribution of its decay products. We perform the study in the rapidity region 2.5 Collapse

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First Measurement of Antideuteron Number Fluctuations at Energies Available at the Large Hadron Collider

The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|η|<0.8) as a function of collision centrality in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations.

Enhanced Deuteron Coalescence Probability in Jets

The transverse-momentum (p_{T}) spectra and coalescence parameters B_{2} of (anti)deuterons are measured in p-p collisions at sqrt[s]=13  TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest p_{T} in the event (p_{T}^{lead}>5  GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE. The coalescence parameter in the jet is found to be approximately a factor of 10 larger than that in the underlying event. This experimental observation is consistent with the coalescence picture and can be attributed to the smaller average phase-space distance between nucleons in the jet cone as compared with the underlying event. The results presented in this Letter are compared to predictions from a simple nucleon coalescence model, where the phase-space distributions of nucleons are generated using pythia8 with the Monash 2013 tuning, and to predictions from a deuteron production model based on ordinary nuclear reactions with parametrized energy-dependent cross sections tuned on data. The latter model is implemented in pythia8.3. Both models reproduce the observed large difference between in-jet and out-of-jet coalescence parameters, although the almost flat trend of the B_{2}^{Jet} is not reproduced by the models, which instead give a decreasing trend.

First-principle insight into the structural, electronic, elastic and optical properties of Cs-based double perovskites Cs2XCrCl6 (X = K, Na)

This study communicates the theoretical investigations on the cubic double perovskite compounds Cs2XCrCl6 (X = K or Na). Density functional theory (DFT) calculations were carried out using the TB-mBJ approximation. These compounds were found to be stable in the cubic perovskite structure having lattice constants in the range of 10.58-10.20. The stability of the investigated materials was assessed by the Gold-Schmidt tolerance method, which resulted in the tolerance factor values of 0.891 and 0.951 for Cs2KCrCl6 and Cs2NaCrCl6, respectively. The calculated values of the elastic constants C11, C12, and C44 of the cubic compounds studied by our research team confirm the elastic stability. The values of the formation energies were also calculated for both the compounds and were found in the range from -2.1 to -2.3. The electronic behavior of the presently investigated materials was examined by inspecting their band structures and the density of states. It was observed that both the materials have half-metallic nature. To check the suitability of the studied compounds in optical applications, we determined the real and imaginary parts of their respective dielectric functions, absorption coefficients, optical conductivities, refractive index, and reflectivity as a function of a wide range of incident photon energies up to 40 eV.

Species Identification and Antifungal Susceptibility Pattern of Candida Isolates in Patients with Vulvovaginitis from Mymensingh, Bangladesh

Vulvovaginal Candidiasis (VVC), a frequent and cumbersome reproductive tract infection affects women's physical and mental health. Although Candida albicans was reported as the most common agent of VVC yet, recently there are significant changes in the pattern of Candida species causing VVC with varying antifungal susceptibility pattern. Therefore this cross-sectional, descriptive type of observational study conducted to identify the spectrum of Candida species associated with VVC and assesses their antifungal susceptibility pattern from March 2021 to February 2022. High vaginal swabs from 175 patients clinically suspected of VVC were collected and cultured on Sabouraud dextrose agar with Chloramphenicol. Species were identified by phenotypic methods like- germ tube test, sub-culture in chromogenic agar media and genotypic methods like- Polymerase chain reaction (PCR), Restriction fragment length polymorphism (RFLP). Antifungal susceptibility was done by disk diffusion method. Out of 175 patients, 52(29.7%) were positive for Candida species. Of the isolates- C. albicans 34(65.0%), Non albicans Candida (NAC) 18(35.0%). Among NAC, C. glabrata 5(9.6%), C. tropicalis 5(9.6%), C. parapsilosis 4(7.7%) and each of C. krusei, C. kefyr, C. ciferrii, C. dubliniensis were 1(1.9%). On susceptibility testing highest resistance was to Clotrimazole 31.0% followed by Nystatin 13.0%, Itraconazole 12.0% and Fluconazole 10.0%. Resistance to azole was higher in NAC than in albicans. Of these patients, 16(31.0%) had history of recurrent VVC (RVVC) of which 12(75.0%) were by NAC, predominantly C. glabrata 5(32.0%). The results showed the increasing incidence of NAC associated vaginitis with higher resistance and recurrence that should be considered in gynecology clinics.

[Endoluminal balloon dilatation of impacted central venous catheter-Case report and literature review]

BACKGROUND

The long-term application of tunneled central venous catheters leads to the development of firm adhesions between the wall of the vein and the catheter, which makes removal of the catheter difficult or impossible. The treatment options in such cases include abandonment of catheter parts or an open surgical approach up to sternotomy. At present, procedural alternatives are available, which include endovascular techniques such as the use of laser energy and endoluminal dilatation.

METHODS

This article describes the successful application of endoluminal dilatation for removal of ingrown central venous catheters in three patients, which had impacted in the superior vena cava and brachiocephalic vein. A 5 Fr (Cordis, Santa Clara, CA, USA) sheath was inserted into one lumen through the severed end of the double lumen catheter. Subsequently, a balloon catheter was inserted into the other lumen to prevent retrograde bleeding or air embolism. Under fluoroscopy a guidewire (0.018, Terumo Medical Corporation, Somerset, New Jersey, USA) was introduced via the sheath to beyond the tip of the hemodialysis catheter into the right atrium. Finally, an angioplasty balloon was inserted (4 × 80 mm) via the guidewire and the complete catheter was sequentially inflated with a pressure of 4 atm. It was then possible to pull out the catheter with no difficulty.

RESULTS

This technique resulted in the removal of the central venous catheters in all three patients, without any relevant complications or resistance.

CONCLUSION

By dissolving adhesions between the catheter and the vein wall, endoluminal balloon dilatation constitutes a reliable and safe technique for the extraction of impacted central venous hemodialysis catheters and may thus help to avoid further invasive surgical procedures.

Abstract 5004: DDR-targeting small molecule inhibitor as a novel therapeutic for treating pancreatic ductal adenocarcinoma

Background: Pancreatic ductal adenocarcinoma (PDAC) is the second most significant cause of cancer-related mortality, with a 5-year survival rate of just 11%. PDACs are one of the most difficult to treat cancers, mainly because of the desmoplastic tumor microenvironment enriched with tumor-supportive extracellular matrix (ECM) and stromal cells. Unfortunately, the efficacies of current pancreatic cancer therapies are limited partly by stroma-mediated drug resistance. We reason that Discoidin Domain Receptors, which belong to the receptor tyrosine kinase family and bind to fibrillar collagens present in the ECM, may be a critical promoter of PDAC growth and progression. Though several drugs targeting DDR proteins have been developed, no inhibitors specific to DDR proteins have been developed. Moreover, those drugs have not been approved for treating PDACs.

Methods. A high throughput screen using small molecule inhibitors was performed to identify bonafide inhibitors of DDR proteins. Structural and reported-based essays were done to determine the specificity. Functional assays were performed to test the potency of the candidate inhibitors. Mechanistic studies were done using RNA-seq, real-time PCR, and western blot.

Results: Using an unbiased screening approach, we identified inhibitors that specifically target DDR proteins. Our studies revealed that small molecule inhibitors blocked the short and long-term viability as well as migration/invasion of PDAC cells. In addition, they induced apoptosis and halted the cell cycle at the G1-S checkpoint. Mechanistic studies revealed that the pro-growth signaling cascade was significantly inhibited.

Conclusions: Our results showing specific DDR inhibitors blocking the growth and progression of PDAC cells without affecting the viability of normal cells suggest that these inhibitors may serve as a safe and potent regimen for treating pancreatic cancers.

Citation Format: Trong Phat Do, Sajid Khan, Daohong Zhou, Matthew Hart, Stanton McHardy, Manjeet Rao. DDR-targeting small molecule inhibitor as a novel therapeutic for treating pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5004.

Abstract 6030: Asparagine metabolism is linked to sex differences in colorectal cancer growth

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in men and women in the United States. We have shown that tumors from female CRC patients have increased asparagine (Asn) which is positively associated with poorer overall survival for female patients only (n=196, stage I-III). Furthermore, analysis of asparagine synthetase (ASNS) expression shows that ASNS is similarly associated with poorer survival for females with CRC only. Currently it is not understood why there are sex-specific differences in tumor metabolism of Asn, or the roles of ASNS in CRC progression. Therefore, we hypothesize that limiting ASNS-driven Asn production is a viable target to suppress CRC development in a sex-specific manner. Therefore, we used a combination of in vitro and in vivo models with human CRC ASNS knock out (KO) cells to generate additional hypotheses that may reveal mechanisms that underlie this finding. Using a 3D spheroid model, we cultured HCT116 ASNS KO and isogenic HCT116 ASNS WT cell lines and modulated Asn supply. During 7 days of growth, depletion of Asn slowed the growth of ASNS KO cells compared to WT, whereas Asn supplementation (400 μM) recovered growth in both cell lines; however, spheroid growth was less in the KO cells. Subcutaneous xenograft of these cell lines in male and female mice (n=10/genotype/sex) showed that loss of ASNS reduced tumor burden in both male and female mice, and improved survival in female mice alone. Pathological assessment of tumors indicated poorly differentiated carcinoma and presence of viable tumor mass in both groups. However, the mitotic activity index, and cellular proliferation (measured by Ki67 staining) was significantly reduced in female ASNS KO mice compared to ASNS WT, showing that the tumor cells with ASNS KO are growing slower than those of ASNS WT counterparts. A multi-omics approach was then used to investigate metabolic pathways and signaling networks altered between the tumor genotypes. Tumor tissue metabolomics revealed significant decreases in nucleotides, amino acids, fatty acids within the ASNS KO compared to WT tumors. Using RNA-Seq, gene set enrichment and Ingenuity Pathway Analysis (IPA), data were integrated revealing disruption to Wnt/B-catenin signaling and immune responses associated with ASNS KO in female mice. Serum metabolomics also revealed a higher ratio of circulating glutamine to glutamate in the female mice with ASNS KO xenografts compared to WT, and a decreased expression of the tumor aspartate-glutamate transporter SLC1A3, therefore tumors with ASNS KO could have decreased ability to transport metabolites needed for Asn generation. In summary we identified that lack of ASNS suppresses tumor progression in a pre-clinical CRC model, and significantly improves survival in female mice only. Validation and further mechanistic experiments will reveal the robustness of this finding.

Citation Format: Caroline Johnson, Oladimeji Aladelokun, Sajid Khan. Asparagine metabolism is linked to sex differences in colorectal cancer growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6030.

Global survival trends for brain tumors, by histology: analysis of individual records for 556,237 adults diagnosed in 59 countries during 2000-2014 (CONCORD-3)

BACKGROUND

Survival is a key metric of the effectiveness of a health system in managing cancer. We set out to provide a comprehensive examination of worldwide variation and trends in survival from brain tumors in adults, by histology.

METHODS

We analyzed individual data for adults (15-99 years) diagnosed with a brain tumor (ICD-O-3 topography code C71) during 2000-2014, regardless of tumor behavior. Data underwent a 3-phase quality control as part of CONCORD-3. We estimated net survival for 11 histology groups, using the unbiased nonparametric Pohar Perme estimator.

RESULTS

The study included 556,237 adults. In 2010-2014, the global range in age-standardized 5-year net survival for the most common sub-types was broad: in the range 20%-38% for diffuse and anaplastic astrocytoma, from 4% to 17% for glioblastoma, and between 32% and 69% for oligodendroglioma. For patients with glioblastoma, the largest gains in survival occurred between 2000-2004 and 2005-2009. These improvements were more noticeable among adults diagnosed aged 40-70 years than among younger adults.

CONCLUSIONS

To the best of our knowledge, this study provides the largest account to date of global trends in population-based survival for brain tumors by histology in adults. We have highlighted remarkable gains in 5-year survival from glioblastoma since 2005, providing large-scale empirical evidence on the uptake of chemoradiation at population level. Worldwide, survival improvements have been extensive, but some countries still lag behind. Our findings may help clinicians involved in national and international tumor pathway boards to promote initiatives aimed at more extensive implementation of clinical guidelines.

Analysis of mitochondrial DNA mutations in Pakistani population diagnosed with cardiovascular diseases

Heart and blood vessel disorders, such as coronary heart disease, brain vessel disease, rheumatic heart disease, and others, are together referred to as cardiovascular disease (CVD). In this study, we sought to determine how mitochondrial Leucine Transfer RNA genes and CVDs are related (MT-L1 and MT-L2). From CVD patients in Peshawar, a total of 27 saliva samples were taken. Leu-tRNA genes expressed by mitochondria were amplified using polymerase chain reaction after DNA was removed. Ten samples were sent for sequencing after PCR and gene cleaning. We obtained all of the sequenced results, which were subsequently aligned and evaluated against the mitochondrial revised Cambridge Reference Sequence (rCRS). However, in our sequenced samples, Leu-tRNA MT-L1 and MT-L2 genes were determined to be unaltered. Thus, it is suggested that a large population be taken into account while screening for mutations in the mitochondrial encoded Leu-tRNA MT-L1 and MT-L2 genes of cardiac patients in areas of Pakistan. Additionally, it is recommended that patients with cardiac problems should also have other mitochondrial encoded genes checked for potential mutations. This could result in the identification of genetic markers that could be used for early CVD screening in Pakistan.