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The circuit implementation of STDP based on memristor is of great significance for the application of neural network. However, recent research shows that the research on the pure circuit implementation of forgetting memristor and STDP is still rare. This paper proposes a new STDP learning rule implementation circuit based on the forgetting memristor. This kind of forgetting memory resistance synapse makes the neural network have the function of time-division multiplexing, but the instability of short-term memory will affect the learning ability of the neural network. This paper analyzes and discusses the influence of synapses with long-term and short-term memory on the learning characteristics of neural network STDP, which lays a foundation for the construction of time-division multiplexing neural network with long-term and short-term memory synapses. Through this circuit, it is found that the volatile memristor has different behaviors to the stimulus signal in different initial states, and the resulting LTP phenomenon is more in line with the forgetting effect in biology. This circuit has multiple adjustable parameters, which can fit the STDP learning rules under different conditions. The application of neural network proves the availability of this circuit.

Phenoxybenzamine has been the standard agent for blockade before adrenalectomy for pheochromocytoma. However, high cost and limited availability have hampered its use. This study investigated whether other agents have supplanted the use of phenoxybenzamine as the first-line agent for alpha blockade in pheochromocytoma.We performed a retrospective analysis of patients in the IBM MarketScan Database who underwent adrenalectomy for pheochromocytoma (2008-2019). Patients were categorized as having been blocked with phenoxybenzamine, selective alpha blockers, calcium channel blockers and/or beta blockers, or none of the above. The outcomes included prescription costs, perioperative costs, and length of stay.A total of 552 patients were identified; 58.7% were female, and the median age was 49 (interquartile range 40-57) years. In total, 291 (52.7%) patients were blocked with phenoxybenzamine, 114 (20.7%) with selective alpha blockers, 42 (7.6%) with only calcium channel blockers and/or beta blockers, and 76 (13.8%) with none. The proportion of patients blocked with phenoxybenzamine decreased from 71.0% in 2008 to 21.2% in 2019. The proportion of patients blocked with selective alpha blockers increased from 6.5% in 2008 to 42.4% and in 2019. The median cost of phenoxybenzamine increased from $722 (interquartile range $441-$1,514) in 2008 to $9,616 (interquartile range $5,049-$16,373) in 2019 (P.001). Length of stay (2 [interquartile range 1-4] days vs 2 [interquartile range 0-3] days) and total perioperative costs ($24,250 [interquartile range $17,462-$33,849] vs $22,098 [interquartile range $16,341-$29,178] between phenoxybenzamine and selective alpha blocker groups were similar.There has been a significant shift away from phenoxybenzamine for preoperative blockade before resection of pheochromocytoma. Selective alpha blockers and calcium channel blockers are increasingly used, likely due to reduced costs, without compromised length of stay or intensive care unit admission.

Neurogenic bladder and bowel are two critical autonomic complications following traumatic spinal cord injury (TSCI). Chronic lower urinary tract and bowel dysfunctions can lead to secondary complications, drastically affect the quality of life and significantly increase the risk of hospital readmission and mortality. Other than symptomatic treatments, a few effective therapies are available. Combined acupuncture and moxibustion therapy has positive effects on improving nerve repair and functional recovery in the early phases following TSCI. However, whether it is effective for TSCI-related chronic urinary and bowel dysfunctions remains unknown. This report presents the case of a 26-year-old male patient who experienced neurogenic bladder and bowel dysfunction following TSCI due to an accidental fall from height for more than 10 months and visited our department for combined acupuncture and moxibustion therapy. After 48 treatment sessions, he regained voluntary urination and defecation to a large extent. Urodynamic testing showed recovered bladder compliance and improved detrusor contractility. Symptom assessment with the Qualiveen Short-Form and neurogenic bowel dysfunction scores demonstrated reduced symptom severity. This case suggests that combined acupuncture and moxibustion therapy might help to restore the physiological functions of the lower urinary and digestive tracts following TSCI and might be a promising alternative for the treatment of neurogenic bladder and bowel dysfunction in patients with TSCI.

Myocardial fibrosis is a fundamental process in cardiac injury. Cardiac magnetic resonance native T1 mapping has been proposed for diagnosing myocardial fibrosis without the need for gadolinium contrast. However, recent studies suggest that T1 measurements can be erroneous in the presence of intramyocardial fat.The purpose of this study was to investigate whether the presence of fatty metaplasia affects the accuracy of native T1 maps for the diagnosis of myocardial replacement fibrosis in patients with chronic myocardial infarction (MI).Consecutive patients (n = 312) with documented chronic MI (6 months old) and controls without MI (n = 50) were prospectively enrolled. Presence and size of regions with elevated native T1 and infarction were quantitatively determined (mean + 5SD) on modified look-locker inversion-recovery and delayed-enhancement images, respectively, at 3.0-T. The presence of fatty metaplasia was determined using an out-of-phase steady-state free-precession cine technique and further verified with standard fat-water Dixon methods.Native T1 mapping detected chronic MI with markedly higher sensitivity in patients with fatty metaplasia than those without fatty metaplasia (85.6% vs 13.3%) with similar specificity (100% vs 98.9%). In patients with fatty metaplasia, the size of regions with elevated T1 significantly underestimated infarct size and there was a better correlation with fatty metaplasia size than infarct size (r = 0.76 vs r = 0.49). In patients without fatty metaplasia, most of the modest elevation in T1 appeared to be secondary to subchronic infarcts that were 6 to 12 months old; the T1 of infarcts12 months old was not different from noninfarcted myocardium.Native T1 mapping is poor at detecting replacement fibrosis but may indirectly detect chronic MI if there is associated fatty metaplasia. Native T1 mapping for the diagnosis and characterization of myocardial fibrosis is unreliable.

Many patients with recurrent high-risk non-muscle invasive bladder cancer after intravesical bacillus calmette-guerin (BCG) face a difficult decision between radical cystectomy (RC) or salvage intravesical therapy (IVT). We sought to determine if there is a difference in overall survival RC and IVT after previous treatment with BCG.We performed a retrospective cohort study of patients with Ta, T1, and Tis bladder cancer treated with induction BCG in the SEER-Medicare dataset from 2000 to 2015. We used a proportional hazards regression model to compare differences in survival between patients having RC and IVT. We adjusted for confounding using a propensity score and stratified our analysis according to timing of treatment and stage at diagnosis.We identified 3940 patients who received either IVT (79%) or RC (21%) following induction BCG. Among patients treated within 12 months of BCG, there was no significant difference in survival between RC and IVT (HR 0.92, 95% CI 0.81-1.04) and 17% of patients having early IVT ultimately required RC. Among patients treated at least 12 months after BCG, RC was associated with worse survival than IVT (HR 1.19, 95% CI 1.06-1.35) and 10% of patients having late IVT ultimately required RC.Among patients with bladder cancer who required additional treatments after induction BCG, we did not observe a difference in overall survival between IVT and RC within 12 months of starting BCG. While RC remains the gold-standard for high risk recurrent NMIBC after BCG, bladder preservation with IVT may be appropriate for well-selected patients.