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Electronic structures and magnetotransport properties of topological Dirac semimetal (TDSM) nanoribbons are studied by adopting the tight-binding lattice model and the Landauer–Büttiker formula based on the non-equilibrium Green's function. For concreteness, the TDSM material Cd3As2 grown along the experimentally accessible [110] crystallographic direction is taken as an example. We found that the electronic structures of the TDSM nanoribbon depend on both the strength and direction of the magnetic field (MF). The transversal local charge density (LCD) distribution of the electronic states in the TDSM nanoribbon is moved gradually from the center toward the hinge of each surface as a [010] direction MF strength is increased, forming the two-sided hinge states. However, one-sided surface states are generated in the TDSM nanoribbon when a [001] direction MF is applied. As a result, one-sided hinge states can be achieved once a tilted MF is placed to the TDSM nanoribbon. The underlying physical mechanism of the desired one-sided hinge states is attributed to both the orbital and Zeeman effects of the MF, which is given by analytical analyses. In addition, typical Aharonov–Bohm interference patterns are observed in the charge conductance of the two-terminal TDSM nanoribbon with a tilted MF. This conductance behaviour originates from the unique interfering loop shaped by the one-sided hinge states. These findings may not only further our understanding on the external-field-induced higher-order (HO) topological phases but also provide an alternative method to probe the HO boundary states. [ABSTRACT FROM AUTHOR]

Neck manipulation is associated with spinal cord injury. However, occurrence of such cases is infrequent. This article presents a 33-year-old gentleman who sustained acute tetraplegia after neck manipulation. The aim of this case report is to create awareness that vigorous neck manipulation could cause injury to the spinal cord.

The use of different types of stains in the quantification of proteins separated on gels using electrophoresis offers the capability of deriving good outcomes in terms of linear dynamic range, sensitivity, and compatibility with specific proteins. An inexpensive, simple, and versatile lighting system based on liquid crystal display backlighting is described. It is used with a flatbed scanner technique previously reported. The results from experimentation and analysis were benchmarked against a commercial densitometer to verify the performance of this analysis system. The availability of this device is expected to be useful in laboratories in schools and in resource-limited venues. (Contains 4 figures.)

Introduction: Double‐filtration plasmapheresis (DFPP) has been utilized for immunomodulation in kidney transplantation. Anticoagulation is important to maintain circuit patency during DFPP. We aimed to compare the efficacy and safety of regional citrate anticoagulation (RCA) with systemic heparin anticoagulation during DFPP in kidney transplant recipients. Methods: A retrospective cohort study was conducted to compare the efficacy and safety of RCA (RCA‐DFPP) to systemic heparin anticoagulation (Hep‐DFPP) for DFPP among kidney transplant recipients in a single tertiary center. Results: A total of 112 sessions of DFPP were performed for 23 subjects, of which 62 sessions were RCA‐DFPP and 50 sessions were Hep‐DFPP. There were 13 sessions (11.6%) of premature circuit clotting, 10 sessions (16.1%) for RCA‐DFPP and 3 sessions (6.0%) for Hep‐DFPP (P =.10). All premature circuit clotting episodes occurred in subjects who underwent DFPP through a vascular catheter. Premature circuit clotting was associated with the use of a vascular catheter (odds ratio [OR] 14.2, 95% confidence interval [CI] 2.7‐73.7; P <.01) and high postfilter ionized calcium (OR 12.7, 95% CI 1.4‐112.5; P <.01). There was no major bleeding event. Hep‐DFPP was associated with higher occurrence of hypocalcemia (OR 1.1, 95% CI 1.0‐1.2; P <.01) and metabolic acidosis (OR 1.4, 95% CI 1.2‐2.0; P =.04), while hypomagnesemia was more common for RCA‐DFPP (OR 2.9, 95% CI 1.1‐7.4; P =.03). Conclusion: Amongst kidney transplant patients who receive DFPP therapy, RCA‐DFPP may be comparable to Hep‐DFPP for the maintenance of circuit patency. Functioning vascular access is vital in avoiding premature clotting of the circuit. Close monitoring of electrolyte imbalances and coagulopathy related to DFPP is recommended. [ABSTRACT FROM AUTHOR]

Background: Patients with multiple myeloma and high serum levels of circulating free light chains (FLC) have increased risk of acute kidney injury (AKI) secondary to cast nephropathy and is associated with poor survival. Despite removal of FLC by medium cutoff (MCO) dialyzer, the role of MCO hemodialysis (HD) in the treatment of cast nephropathy and its clinical benefits remain unknown. Methods: A systematic review was conducted to establish the effectiveness of MCO dialyzer and clinical outcomes, compared to other forms of dialyzers in the removal of FLC, in myeloma patients with AKI. The primary outcome was effectiveness of MCO‐HD in reducing serum FLC. The secondary outcomes were HD independence, estimated glomerular filtrate rate, mortality rates, length of hospitalization, rebound of serum FLC before the next dialysis, removal of other molecules during dialysis, and adverse events. Results: We identified three case series, with a total of 17 patients. There were no randomized controlled trials (RCTs) or cohort studies. These case series showed that MCO dialyzer was effective in the removal of FLC and led to a reduction in FLC concentration post‐dialysis. The majority of the case series did not have comparator arm and renal and/or other clinical outcomes. Conclusion: MCO dialyzer appeared to be effective in the removal of FLC based on the existing limited data. However, more data, particularly large‐scale RCTs, are needed to assess the use of MCO dialyzer in reducing serum FLC and its effect on clinical outcomes in patients with multiple myeloma and AKI. [ABSTRACT FROM AUTHOR]

Flatbed scanner densitometers can be operated under various illumination and recording exposure levels. In this work, we show that optical density measurement accuracy, sensitivity, and stability of stained polyacrylamide electrophoresis gel densitometry are crucially dependent on these two factors (brightness and exposure level), notwithstanding that the source is monochromatic, spatially uniform, and the measurements are made using an accurately calibrated step wedge in tandem. We further outline a method to accommodate the intensity deviations over a range of illumination and exposure levels in order to maintain sensitivity and repeatability in the computed optical densities. Comparisons were also made with results from a commercial densitometer. [c] 2010 Optical Society of America OCIS codes: 110.0110, 120.0120, 170.0170.

Introduction: Double-filtration plasmapheresis (DFPP) may be used for immunomodulation in kidney transplant (KTx). While DFPP reduces plasma product exposure, risk of circuit clotting merits adequate anticoagulation. Regional citrate anticoagulation (RCA) avoids the risks of systemic anticoagulation, but a protocol for RCA-DFPP is not previously widely described. Methods: We conducted a single-center retrospective cohort study involving adult (≥21 years old) KTx recipients who underwent RCA-DFPP from 2018 to 2020 to investigate efficacy and safety for an RCA protocol during DFPP in KTx recipients. Results: Fifty-one (85%) of 60 RCA-DFPP sessions in 17 patients completed without circuit clotting. Circuit clotting was associated with high post-filter ionized calcium (28 vs. 3.7%, odds ratio 10.1, 95% CI 1.1–89.4, p = 0.037). Hypo- and hypercalcemia developed in 5 (8.3%) and 8 (13.3%) sessions, respectively, but no adverse effects were noted despite severe hypocalcemia in one. There was no significant change in pre- and post-RCA-DFPP sodium, bicarbonate, albumin, and platelet levels. With regards DFPP procedure, prolongation of prothrombin time (PT) and activated partial thromboplastin time (aPTT) was observed following 38 (64.4%) and 12 (20.3%) sessions, respectively. Severely prolonged (>1.5 × upper limit normal) PT and aPTT were recorded in 2 sessions each. Expectedly, hypofibrinogenemia developed after 31 (51.7%) sessions: including 4 (6.7%) severe hypofibrinogenemia (<0.5 g/L). Two patients developed bleeding requiring blood product transfusion. The median total volume of fluids administered per session was 1.495 (1.373–1.612) L; post-RCA-DFPP significant weight gain of 0.5 (0–1.25) kg was noted. Diuretic was commenced or dose increased following 20 (33.3%) sessions for fluid balance management. Discussion/Conclusion: Protocol-based RCA for DFPP is feasible and safe in KTx recipients. However, DFPP-related coagulopathy can develop consequent to treatment; caution should be exercised for patients with bleeding risk. Close monitoring and management of the patients' electrolytes, especially hypocalcemia and hypomagnesemia, and fluid status is recommended. [ABSTRACT FROM AUTHOR]