Clinical characteristics of survivors versus non-survivors after acute diquat poisoning: a comparative study.

The aim of this study was to compare the clinical characteristics between survivors and non-survivors after acute diquat (DQ) poisoning. Patients treated in the Emergency Department of Fu Yang People's Hospital for DQ poisoning between January 2018 and February 2022 were enrolled in this retrospective comparative study. A total of 65 patients were collected, including 36 males (55.4%) and 29 females (44.6%). There were 34 survivors (52.3%), and 31 non-survivors (47.7%). Patients in the non-survivor group were significantly older (P = 0.003), received a higher dose of DQ before admission (P < 0.001), had more severe organ damage (P < 0.001), lower respiration rate (P < 0.001) and enema (P = 0.009), lower GCS score (P = 0.038), and higher SIRS score (P = 0.018) and APACHE-II score (P < 0.001) than patients in the survivor group. Additionally, biochemical indicators after admission between survivors and non-survivors were significantly different (all P < 0.05). Multivariate logistic regression analysis showed that respiratory failure (P = 0.021), the dose of DQ (P = 0.022), respiratory rate (P = 0.007), and highest alanine transaminase (ALT) level after admission (P = 0.030) were independent risk factors for acute DQ-induced death. These data suggest that non-survivors with acute DQ poisoning are more likely to suffer from respiratory failure, have higher respiratory rate and ALT after admission, and are exposed higher doses of DQ before admission than survivors.

A multi-module energy-saving pulsed magnetic field generator.

In order to generate the unipolar and bipolar pulsed magnetic fields and improve the energy efficiency of the magnetic field generator, a multi-module energy-saving (MMES) pulsed magnetic field generator is designed. The circuit topology of the MMES pulsed magnetic field generator is presented and the experimental data are measured by experiments. The results show that the peak current values of unipolar and bipolar pulsed magnetic fields are 156 A and 154 A by discharging two capacitors, and the intensities are 87.6 mT and 86.5 mT, respectively. The energy-saving rates of unipolar and bipolar pulsed magnetic fields can be up to 17.64% and 19.36%, respectively. Therefore, it has very high application and research value in the field of biological magnetism therapy.

A multifunctional energy-saving magnetic field generator.

To improve the energy utilization of magnetic field generators for biological applications, a multifunctional energy-saving magnetic field generator (ESMFG) is presented. It is capable of producing both an alternating magnetic field (AMF) and a bipolar pulse magnetic field (BPMF) with high energy-saving and energy-reuse rates. Based on a theoretical analysis of an RLC second-order circuit, the energy-saving and energy-reuse rates of both types of magnetic fields can be calculated and are found to have acceptable values. The results of an experimental study using the proposed generator show that for the BPMF, the peak current reaches 130 A and the intensity reaches 70.3 mT. For the AMF, the intensity is 11.0 mT and the RMS current is 20 A. The energy-saving and energy-reuse rates for the AMF generator are 61.3% and 63.5%, respectively, while for the BPMF generator, the energy-saving rate is 33.6%. Thus, the proposed ESMFG has excellent potential for use in biomedical applications.

Sphingobium chlorophenolicum dichlorohydroquinone dioxygenase (PcpA) is alkaline resistant and thermally stable.

Dichlorohydroquinone dioxygenase (PcpA) is the ring-cleavage enzyme in the PCP biodegradation pathway in Sphingobium chlorophenolicum strain ATCC 39723. PcpA dehalogenates and oxidizes 2,6-dichlorohydroquinone to form 2-chloromaleylacetate, which is subsequently converted to succinyl coenzyme A and acetyl coenzyme A via 3-oxoadipate. Previous studies have shown that PcpA is highly substrate-specific and only uses 2,6-dichlorohydroquinone as its substrate. In the current study, we overexpressed and purified recombinant PcpA and showed that PcpA was highly alkaline resistant and thermally stable. PcpA exhibited two activity peaks at pH 7.0 and 10.0, respectively. The apparent k(cat) and K(m) were measured as 0.19 ± 0.01 s(-1) and 0.24 ± 0.08 mM, respectively at pH 7.0, and 0.17 ± 0.01 s(-1) and 0.77 ± 0.29 mM, respectively at pH 10.0. Electron paramagnetic resonance studies showed rapid oxidation of Fe(II) to Fe(III) in PcpA and the formation of a stable radical intermediate during the enzyme catalysis. The stable radical was predicted to be an epoxide type dichloro radical with the unpaired electron density localized on C3.

Anticancer activity of the PR domain of tumor suppressor RIZ1.

Human tumor suppressor gene RIZ encodes two protein products, tumor suppressor RIZ1 and proto-oncoprotein RIZ2, which regulate cellular functions in a Yin-Yang fashion. The only structural difference between them is that RIZ2 lacks the N-terminal PR domain. In this study, we showed that RIZ1 mRNA expression level was elevated in stage IV of eight different types of cancer (stage III for prostate cancer), indicating that RIZ1 might play an important role in tumor metastasis, and the PR domain alone possessed anticancer activity.

Functional mechanisms for human tumor suppressors.

Tumor suppressors refer to a large group of molecules that are capable of controlling cell division, promoting apoptosis, and suppressing metastasis. The loss of function for a tumor suppressor may lead to cancer due to uncontrolled cell division. Because of their importance, extensive studies have been undertaken to understand the different functional mechanisms of tumor suppressors. Here, we briefly review the four major mechanisms, inhibition of cell division, induction of apoptosis, DNA damage repair, and inhibition of metastasis. It is noteworthy that some tumor suppressors, such as p53, may adopt more than one mechanism for their functions.

Cloning, expression, purification and crystallization of the PR domain of human retinoblastoma protein-binding zinc finger protein 1 (RIZ1).

Through alternative promoter usage, human retinoblastoma protein-interacting zinc finger gene RIZ encodes two different protein products, RIZ1 and RIZ2, which have been identified to be a tumor suppressor and a proto-oncoprotein, respectively. Structurally, the two protein products share the same amino acid sequences except that RIZ2 lacks an N-terminal PR domain with methyltransferase activity. Previous studies have shown that over-expression of RIZ2 is usually associated with depressed RIZ1 expression in different human cancers. It is generally believed that RIZ1 and RIZ2 regulate normal cell division and function using a "Yin-Yang" fashion and the PR domain is responsible for the tumor suppressing activity of RIZ1. In order to better understand the biological functions of the PR domain by determining its three-dimensional crystal structure, we expressed, purified and crystallized a construct of the PR domain (amino acid residues 13-190) in this study. The maximum size of the needle-shaped crystals was approximately 0.20 x 0.01 x 0.01 mm.