[Establishment and evaluation of a new method for determining hemodynamics of pulmonary hypertension rats]

Objective: By evaluating the hemodynamic parameters such as cardiac output (CO), right ventricular pressure (RVP), pulmonary artery pressure (PAP) and total pulmonary resistance index (TPRI) in pulmonary hypertension rat model, we established a more comprehensive hemodynamic evaluation system, which objectively evaluated the severity of disease and exercise tolerance in rats with pulmonary hypertension. Methods: SD rats were randomly divided into a control group and a model group with 5 rats in each group. The model group was intraperitoneally injected with SU5416 (20 mg/kg) and placed in an oxygen chamber at a 10% oxygen concentration for 21 days and then placed in a normoxic environment for 14 days. After modeling, rats were anesthetized and mechanically ventilated. The operator cut the skin along the right paraxial line, detached and ligated the intercostal artery, and then cut off the 3 and 4 ribs, exposing the heart and freeing aortic root about 0.2 cm. The flowmeter probe was set in the dissected aortic segment, and real-time recording time, blood flow waveforms, cardiac output were calculated accordingly. Then the needle attached to the baroreceptor was inserted into the right ventricle and the system acquired the right ventricular time-pressure waveform. After the waveform stabilized for about 30 seconds, the end of the cannula was sent to the pulmonary artery trunk through the entrance of the pulmonary artery to record the time-pressure curve of the pulmonary artery. Results: RVSP, PASP, PADP and mPAP in the model group were significantly higher than those of the control group [ RVSP(23.4±5.4) mmHg, 1 mmHg=0.133 kPa vs (56.4±13.0) mmHg, PASP (22.8±4.4) mmHg vs (58.5±14.9) mmHg, PADP (9.7±1.9) mmHg vs (30.3±7.0) mmHg, mPAP (14.1±2.7) mmHg vs (41.9±8.0) mmHg, all P<0.05 ]. Compared with the control group, the cardiac index in the model group was significantly lower [ CI (0.54±0.08) ml·min(-1)·g(-1) vs (0.40±0.09) ml·min(-1)·g(-1,) P=0.02 ]. Furthermore, compared with the control group, pulmonary vascular resistance index was significantly increased in the model group[PVRI (0.27±0.03) mmHg·ml(-1)·min(-1)·kg(-1) vs (0.06±0.01) mmHg·ml(-1)·min(-1)·kg(-1,) P<0.05]. The pathological results also showed that the middle part of pulmonary arterioles in the model group had muscular hypertrophy and muscular pulmonary arterioles, and even plexiform lesions. Conclusion: In this study, we established a new method that simultaneously determined several hemodynamic parameters such as RVSP, PASP, PADP, CO, CI and PVRI, which provided a more comprehensive assessment of hemodynamic changes in pulmonary hypertension rat models.

[Method for recording tension changes of small pulmonary artery and vein using the isolated vessel tension measurement system]

Objective: To establish a standardized method for isolated pulmonary artery and vein rings with different diameter, pressure and length, which could provide a more scientific method for in vitro study of pulmonary vessel diseases. Methods: Male SD rats were anesthetized, and the right ventricular systolic pressure were measured. Small pulmonary artery and vein rings with 200-400 μm in diameter and 2 mm in length were prepared by dissecting pulmonary arteries and veins. The pulmonary vessel rings were mounted in the organ bath by 2 stainless steel wires with diameter of 40 μm. Then the internal circumference of the vessel rings was increased gradually with 100 μm per step. At the same time the vascular tension was recorded by the Myograph System and Acknowledgement data acquisition system, and subsequently the passive length-tension exponential curve was made. The initial tension of the rings was set, equilibrated for another 30 min, and then stimulated with 60 mmol/L KCl 3 times, and the best contractile reactivity was achieved. The contractile reactivity of pulmonary artery rings and endothelial integrity were detected by exposure to 1 μmol/L phenylephrine(PE) and 10 μmol/L acetylcholine(Ach), while the contractile reactivity of pulmonary vein rings was detected by exposure to 1 μmol/L U46619 and 10 μmol/L papaverine. Results: The contraction and relaxation effects of the pulmonary artery rings reached 0.39 mg and 92% when they were stimulated by 1 μmol/L PE and 10 μmol/L Ach. The contraction and relaxation effects of pulmonary vein rings were up to 0.13 mg and 84% when they were exposed to 1 μmol/L U46619 and 10 μmol/L papaverine, respectively. Conclusion: Pulmonary artery and vein rings with appropriate basal tension and optimal vasodilator activity were prepared, and a standardized method of tension experiment for isolated pulmonary artery and vein rings established.

Drug-induced hypersensitivity syndrome caused by valproic acid as a monotherapy for epilepsy: First case report in Asian population

Valproic acid (VPA) is a broad-spectrum antiseizure drug used for a variety of clinical conditions, such as epilepsy and mood disorders. Drug-induced hypersensitivity syndrome (DRESS) accompanied by hyponatremia, thrombocytopenia, hypoalbuminemia and elevated aminotransferase has never been reported as an adverse effect of VPA monotherapy during titration for epilepsy in Asian population. Hereby, we present the case of a 73-year-old Chinese male who suffered from DRESS and other complications two weeks after initiating VPA treatment for epilepsy. Understanding the risk associated with VPA-induced DRESS, and taking effective measures to avoid the severe side effects are necessary.

Synthesis of graphene-like g-C3N4/Fe3O4 nanocomposites with high photocatalytic activity and applications in drug delivery

Graphene-like g-C₃N₄ nanosheet/Fe₃O₄ nanocomposites with high photocatalytic activity and applications for magnetically targeted drug delivery.

Isolation and characterization of Aeromonas schubertii from diseased snakehead, Channa maculata (Lacepède)

Pure bacterial cultures were isolated from diseased snakeheads, Channa maculata (Lacepède), suffering high mortality in a farm in Zhongshan, southern China. Three isolates, namely ZS20100725, ZS20100725-1 and ZS20100725-2, were identified as Aeromonas schubertii. All the isolates showed high 16S rRNA sequence similarities with A. schubertii. The isolates exhibited strong virulence to snakeheads in experimental challenges with LD(50) ranging between 1.4 × 10(4) and 6.4 × 10(6) CFU g(-1). Two of the isolates were positive for haemolysin, elastase, lipase and lecithinase by phenotypic determination, which was further confirmed by PCR amplification of the haemolysin and elastase genes. In sterile liquid medium, the best growth conditions of strain ZS20100725 were 30 °C, pH 7 and 0.5% salinity (w/v). Antibiotic susceptibility tests showed that strain ZS20100725 was susceptible to cefoxitin, cefoperazone and chloramphenicol. Furthermore, histopathology of diseased snakeheads infected with A. schubertii showed necrosis and congestion in liver, kidney and spleen and also damage to the cardiac muscle, intestine and gills.

Association between carbamazepine-induced cutaneous adverse drug reactions and the HLA-B*1502 allele among patients in central China

The aim of this study was to investigate the association between carbamazepine (CBZ)-induced cutaneous adverse drug reactions (cADRs) and the HLA-B*1502 allele among patients from central China. Eight patients with Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN), 28 with mild maculopapular eruptions (MPEs), 50 CBZ-tolerant controls, and 71 healthy volunteers were recruited. HLA genotyping was performed using the polymerase chain reaction sequence-based typing (SBT) method. As a result, the HLA-B*1502 allele was observed at the following rates: (1) 100% (8/8) among those with CBZ-induced SJS/TEN, (2) 10.7% (3/28) among those with CBZ-induced MPEs; (3) 8.0% (4/50) among CBZ-tolerant controls; (4) 8.5% (6/71) among healthy volunteers. The eight patients with SJS/TEN positive for the HLA-B*1502 allele had an odds ratio (OR) of 184 compared with CBZ-tolerant controls. There was no significant difference in frequency between patients with MPEs and CBZ-tolerant controls (P>0.05). Thus, CBZ-induced SJS/TEN, but not MPEs, is strongly associated with HLA-B*1502. Testing for HLA-B*1502 should be recommended for patients from central China prior to initial CBZ treatment.

Homogeneous and inhomogeneous phase transitions in the Blume-Capel model with random bonds

Using mean field approximation, we investigate the Blume-Capel model with random bond. The system is self-organized into blocks, which behave like superspins and are coupled with their neighbors. The methods to search the elementary blocks and calculate their coupling are proposed. For the strongly disordered case, the coupling distribution is exponential and the phase transition should be inhomogeneous. This physical picture should be common in various phase transition in quenched disordered systems.

Interpenetration in [Cd(isonicotinate)2(1,2-bis(4-pyridyl)-ethane)0.5(H2O)]n, a novel octahedral polymer containing an unusual two-dimensional bilayer motif generated by self-assembly of rectangle building blocks

A hydrothermally synthesized mixed-ligand molecular solid composed of pillared bilayers has been formulated; it presents a new remarkable three-dimensional architecture sustained by the catenation of two-fold decked layers, and exhibits intense photoluminescence upon photoexcitation at 314 nm.

High resolution spectral analysis of 13CH3OH in the excited torsional states

In this work, we have extended our previous analysis of the Hamiltonian of 13C substituted methanol to include a large number of spectral lines involving the second excited torsional state using an improved model. The data set consisted of 2529 Fourier transform and microwave transitions with the rotational angular momentum J < or = 10, K < or = 6 and n < or = 2 (with 336 MW lines). The data set was fitted with the new Hamiltonian model to derive the molecular parameters. The results indicate that the model developed for the other methanol species (CH3OH, CH3(18)OH and CH3OD) is also valid for the C-13 substituted species. The results will allow the energy levels of the molecule to be calculated for higher torsional levels above the internal rotational barrier with improved precision and allow the analysis to be carried out for more excited torsional states.

[An experimental study and preliminary clinical report of shape-memory sawtooth-arm embracing internal fixator]

The sawtooth-arm internal embracing fixator is made of Nickel-Titanium shape memory alloy and consists of 3 components: body, arms and sawteeth. In cross section a 2/3 circumference is constructed by body and arms of the fixator. The free ends of the arms which exceed the semi-circle are bent more medially so that it can match the requirement of fixation of long tubular bone whose cross section is not a regular circle. The embracing fixator has two types: the cylinder type is for use in the middle part and the cone type is either for the proximal or distal 1/3 of the shaft of long tubular bone. The animal experimental studies and in vitro mechanical tests demonstrated that the embracing fixator possesses good anti-bending and anti-torsion effects, and its resisting compression effect was much lower than that of bone plate. These characteristics are beneficial for enhancing fracture healing, reducing post fixation osteoporosis and providing a new, simple and effective method for the treatment of long tubular bone fracture. The fixator has already been used in the treatment of fractures of femur, humerus, radius and ulna with good results.