Pacemaker electrode rupture causes recurrent syncope: A case report.

BACKGROUND: Currently, the implantation of permanent cardiac pacemakers entails mostly subclavian vein puncture, which is relatively simpler and easier to master. However, due to individual differences, some patients carry a narrow space between the clavicle and the first rib. If the range of activity of the upper limb is increased, the friction between the electrode wire and the bone gap leads to the breakage of the electrode wire, which is manifested by poor pacemaker perception and pacing. CASE SUMMARY: A 68-year-old woman underwent permanent pacemaker implantation in our hospital because of third-degree atrioventricular block 6 years ago. At that time, the patient was recommended to have a dual-chamber permanent pacemaker implantation, and finally chose a single-chamber permanent pacemaker because she could not afford the cost. The patient has repeatedly lost consciousness for no obvious reason in the past 3 d, and went to our hospital for treatment. The chest X-ray showed that the pacemaker electrode was broken. After the patient was given a pacemaker electrode replacement, the patient did not continue to lose consciousness. CONCLUSION: Because the electrodes implanted in the subclavian approach are close to the clavicle and the first rib, the pacemaker electrodes may wear out. If the patient loses consciousness again after the pacemaker is implanted, we should consider whether there is a pacemaker. The possibility of electrode breakage, and timely help the patient to replace the new pacemaker electrodes.

Amiodarone-induced muscle tremor in an elderly patient: A case report.

BACKGROUND: Amiodarone is a Class III antiarrhythmic drug, which has been adopted for the treatment of atrial fibrillation and ventricular arrhythmia. However, the use of amiodarone can cause lower limb muscle tremors, which is recognized as a rare side effect of this medication. CASE SUMMARY: An 84-year-old female was administrated with amiodarone for paroxysmal supraventricular tachycardia and frequent ventricular tachycardia. The patient developed a bilateral gastrocnemius tremor in the course of medication, and the strength of the patient's bilateral knee flexor and extensor reached 4/5 and 3/5, respectively. After the use of amiodarone was stopped, and the patient was given a small dose of levetiracetam, the lower limb tremor symptoms were significantly mitigated, along with activity and function. CONCLUSION: Attention should be paid to the significance of the side effects of drugs in the elderly, which may be atypical in the elderly. The relevant side effects of drugs may not be as rare as reported due to individual differences and different pharmacokinetics. If the side effects are generated, the medication should be adjusted in time, and the progress of the side effects should be intervened.

Congenital absence of the right coronary artery: A case report.

BACKGROUND: As a rare anomaly, congenital absence of the right coronary artery (RCA) occurs during the development of coronary artery. Patients with congenital absence of the RCA often show no clinical symptoms, and this disease is considered benign. The left coronary artery gives blood supply to the whole myocardium. The prevalence of congenital absence of the RCA is approximately 0.024%-0.066%. There are few cases reported as for this disease. In this work, a patient, with congenital absence of the RCA diagnosed by coronary angiography (CAG), was described. CASE SUMMARY: A 41-year-old man arrived at our hospital for treatment, due to the repeated palpitations for a duration of one year. Considering the possibility of coronary heart disease, the patient underwent CAG that indicated the congenital absence of the RCA. Unfortunately, the patient refused to accept computed tomography coronary angiography (CTCA), to further confirm the congenital absence of the RCA. CONCLUSION: Single coronary artery is a rare type of coronary artery abnormality, which usually has no obvious clinical manifestations and is considered as a benign disease. CAG is the main means by which congenital absence of the RCA can be diagnosed, and the disease can also be further confirmed by CTCA.

Preparation, characterization and photocatalytic activities of boron- and cerium-codoped TiO2.

Boron- and cerium-codoped TiO2 photocatalysts were synthesized using modified sol-gel reaction process and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), particle size distribution (PSD), diffuse reflectance spectra (DRS), and Brunauer-Emmett-Teller (BET). The photocatalytic activities were evaluated by monitoring the degradation of dye Acid Red B (ARB). The results showed that the prepared photocatalysts were mixed oxides mainly consisting of titania, ceria, and boron oxide. The structure of TiO2 could be transformed from amorphous to anatase and then to rutile by increasing calcination temperature; the transformation being accompanied by the growth of particle size without any obvious change in phase structure of CeO2. The XPS of B(1.6)Ce(1.0)-TiO2 prepared at 500 degrees C showed that a few boron atoms were incorporated into titania and ceria lattice, whereas others existed as B2O3. Cerium ions existed in two states, Ce3+ and Ce4+, and the atomic ratio of Ce3+/Ce4+ was 1.86. When boron and cerium were doped, the UV-Vis adsorption band wavelength showed an obvious shift toward the visible range (< or =526 nm). As the atomic ratio of Ce/Ti increased to 1.0, the absorbance edge wavelength increased to 481 nm. The absorbance edge wavelength decreased for higher cerium doping levels (Ce/Ti = 2.0). The particles size ranged from 122 to 255 nm with a domain at 168 nm (39.4%). The degradation of ARB dye indicated that the photocatalytic activities of boron- and cerium-codoped TiO2 were much higher than those of P25 (a standard TiO2 powder). The activities increased as the boron doping increased, whereas decreased when the Ce/Ti atomic ratio was greater than 0.5. The optimum atomic ratio of B/Ti and Ce/Ti was 1.6 and 0.5, respectively.

[Preparation and photocatalytic activity of boron doped CeO2/TiO2 mixed oxides].

Boron doped CeO2/TiO2 mixed oxides photocatalysts were prepared by adding boric acid and cerous nitrate during the hydrolyzation of titanium trichloride and tetrabutyl titanate. XRD, UV-Vis DRS and XPS techniques were used to characterize the crystalline structure, light absorbing ability and the chemical state of Boron element in the photocatalyst sample. The photocatalytic activities were evaluated by monitoring the degradation of acid red B under UV irradiation. These results indicate that the wavelengths at adsorbing edge are affected by the content of cerous nitrate and the maximum absorption wavelength is about 481 nm when the mole ratio of Ce/Ti is 1.0. For higher dosage of Cerium, the absorbance edge shifts to blue slightly. The prepared photocatalyst is composed of anatase TiO2 and cubic CeO2 when calcined at 500 degrees C. An increase in the calcination temperature transforms the crystalline structure of the titanium oxides from anatase to rutile, and has no obvious influence on crystalline structure of CeO2 but crystallites growth up. The absorbance edge decreases drastically with the increase of calcination temperature. With a view to the stability of photocatalyst and utilization of sun energy, 500 degrees C of calcination temperature is recommended. The XP spectrum for B1s exhibits that only a few boron ions dope into titania and ceria matrix, others exist in B2O3. The photocatalytic activity increases with increase of cerous nitrate dosage, and decreases drastically due to higher dosage (the mol ratio of Ce/Ti > 0.5). After 10 min UV irradiation, 96% of acid red B is degraded completely over photocatalyst under optimum reaction condition.

[Degradation of reactive red X-3B by ultra sound synergized with zero-valent iron].

The synergistic effects of ultra sound and zero-valent iron were studied by measuring the degradation of X-3B in zero-valent reduction, ultra sound degradation and synergistic systems. The effects of pH, ultra sound power and irradiation time on the synergistic system were explored. The results show that the X-3B is degraded difficultly by ultra sound and the total removal rate is less than 7.75% after 25min ultrasonic irradiation. When pH is 5.0, 7.0 and 9.0, the degradation rate of X-3B in synergistic system is about 1.68, 1.76 and 1.67 times, respectively, than the total removal rate of zero-valent iron reduction plus ultrasound degradation. After 25min ultrasonic irradiation in synergistic system, 99.42% of X-3B is removed at pH7.0. However, the degradation rate of X-3B in zero-valent iron reduction system is much higher than that of synergistic system at pH3.0. The degradation mechanism of X-3B in zero-valent iron reduction system is different from that of synergistic system. The X-3B is degraded into intermediate pollutants in the former, but is degraded completely in the latter. Accordingly, the X-3B can be degraded effectively in the synergistic system of zero-valent iron and ultra sound, when pH is 5.0 approximately 7.0 and the power of ultra sound is 400 approximately 600W.

[Characterization and photocatalytic activity of Ni-doped tiO2 nano photocatalysts prepared by low temperature combustion synthesis].

Ni-doped TiO2 photocatalysts were prepared by low temperature combustion synthesis and some properties, such as optical absorption, crystal type, grain size distribution and chemistry transformation during temperature rising were characterized by UV-Vis DRS, X-ray diffraction (XRD), laser light dispersion grain size measurement machine and TG-DSC respectively. The photocatalytic activities of the prepared photocatalysts under visible light irradiation were evaluated by monitoring the degradation of methylene blue dye, a probe pollutant. The results indicate that the Ni-doped TiO2 photocatalysts prepared by low temperature combustion synthesis shift the optical absorption threshold to visible light, the band gap of 0.4 Ni-TiO2 (atomic ratio) is 2.3 eV, which corresponds to a 564 nm threshold in the visible light range. The crystal type of photocatalyst is anatase TiO2 and the content of NiTiO3 rise with the increase of Ni dopant. The grain size of photocatalyst distributes from 50 to 150nm, which account for 96.9% of entire quantity. During temperature rising, the TiO2 phase in photocatalyst transforms from amorphous structure to anatase and NiTiO3 crystallites appear at 445.2 degrees C. After 150 min visible light irradiation, 93.9% of methylene blue dye are degraded over 0.4 Ni-TiO2 photocatalyst. The photocatalytic activity of Ni doped TiO2 is higher than that of P25 under identical conditions.

[Photocatalytic degradation of reactive red X-3B by immobilized P25 in a contact oxidation reactor].

The immobilized photocatalyst, P25 supported by glass fiber, was prepared by calcining method. The effect of calcining temperature on the photocatalytic activity and the effect of initial pH and inorganic anions on the photocatalytic degradation of Reactive Red X-3B were explored in a new photocatalytic contact oxidation reactor. The results show that catalyst activity is affected drastically by calcining temperature, the optimal temperature is 300 degrees C; the SEM photos of immobilized catalyst indicated that P25 adhered to glass fiber firmly; The Reactive Red X-3B was more easily degraded in acid solution, when initial pH increasing from 2.0 to 10.0, the degradation rate of Reactive Red X-3B decreased from 90.06% to 42.71%; inorganic anions, CO3(2-) and SO4(2-), had little effect on the degradation of Reactive Red X-3B. However, the degradation of Reactive Red X-3B significantly decreased, 17.03% down, in the presence of Cl-. So it was a good alternate scenario to conduct photocatalytic oxidation by using immobilized P25 in a contact oxidation reactor.