The role of RNF138 in DNA end resection is regulated by ubiquitylation and CDK phosphorylation.

Double-strand breaks (DSBs) are DNA lesions that pose a significant threat to genomic stability. The repair of DSBs by the homologous recombination (HR) pathway is preceded by DNA end resection, the 5' to 3' nucleolytic degradation of DNA away from the DSB. We and others previously identified a role for RNF138, a really interesting new gene finger E3 ubiquitin ligase, in stimulating DNA end resection and HR. Yet, little is known about how RNF138's function is regulated in the context of DSB repair. Here, we show that RNF138 is phosphorylated at residue T27 by cyclin-dependent kinase (CDK) activity during the S and G2 phases of the cell cycle. We also observe that RNF138 is ubiquitylated constitutively, with ubiquitylation occurring in part on residue K158 and rising during the S/G2 phases. Interestingly, RNF138 ubiquitylation decreases upon genotoxic stress. By mutating RNF138 at residues T27, K158, and the previously identified S124 ataxia telangiectasia mutated phosphorylation site (Han et al., 2016, ref. 22), we find that post-translational modifications at all three positions mediate DSB repair. Cells expressing the T27A, K158R, and S124A variants of RNF138 are impaired in DNA end resection, HR activity, and are more sensitive to ionizing radiation compared to those expressing wildtype RNF138. Our findings shed more light on how RNF138 activity is controlled by the cell during HR.

SUMOylation mediates CtIP's functions in DNA end resection and replication fork protection.

Double-strand breaks and stalled replication forks are a significant threat to genomic stability that can lead to chromosomal rearrangements or cell death. The protein CtIP promotes DNA end resection, an early step in homologous recombination repair, and has been found to protect perturbed forks from excessive nucleolytic degradation. However, it remains unknown how CtIP's function in fork protection is regulated. Here, we show that CtIP recruitment to sites of DNA damage and replication stress is impaired upon global inhibition of SUMOylation. We demonstrate that CtIP is a target for modification by SUMO-2 and that this occurs constitutively during S phase. The modification is dependent on the activities of cyclin-dependent kinases and the PI-3-kinase-related kinase ATR on CtIP's carboxyl-terminal region, an interaction with the replication factor PCNA, and the E3 SUMO ligase PIAS4. We also identify residue K578 as a key residue that contributes to CtIP SUMOylation. Functionally, a CtIP mutant where K578 is substituted with a non-SUMOylatable arginine residue is defective in promoting DNA end resection, homologous recombination, and in protecting stalled replication forks from excessive nucleolytic degradation. Our results shed further light on the tightly coordinated regulation of CtIP by SUMOylation in the maintenance of genome stability.

Management and outcomes of pregnant ICU patients with severe COVID-19 pneumonia in Qatar: A retrospective cohort study.

INTRODUCTION: Pregnant women are considered a high-risk group for COVID-19 due to their increased vulnerability to viral infections. The impact of COVID-19 on pregnant women is not well understood, and there is a need for data on managing severe COVID-19 in pregnant patients. This retrospective descriptive cohort study described the characteristics, hospital stay, interventions, and outcomes of pregnant patients admitted to the intensive care units (ICUs) with severe COVID-19 pneumonia in Qatar. METHODS: Data were collected from medical records and chart reviews of pregnant women admitted to Hamad Medical Corporation (HMC) with COVID-19 pneumonia from March 01, 2020, to July 31, 2021. The inclusion criteria encompassed pregnant women with a positive polymerase chain reaction (PCR) antigen test or radiological changes at admission, requiring respiratory support, and hospitalized for more than 24 hours. RESULTS: A total of 43 pregnant women were included in this study. Most patients were admitted during the first wave of the pandemic, with a median gestational age of 212 days [interquartile range 178-242 days] at presentation. The most common respiratory support methods were high-flow nasal cannula, non-invasive positive pressure ventilation, and invasive positive pressure ventilation. Convalescent plasma therapy was administered to 58% of patients, and tocilizumab was used in 28%. Renal replacement therapy was required by 4.6% of patients and 7% required extracorporeal membrane oxygenation. CONCLUSION: This study provides valuable insights into the impact of COVID-19 on pregnant patients admitted to the ICUs in Qatar. The results suggest that pregnant patients with COVID-19 pneumonia require close monitoring and appropriate interventions to minimize adverse outcomes for both mother and fetus. The data may contribute to future guidelines and management strategies for severe COVID-19 in pregnant patients.

The Role of DNA Repair in Genomic Instability of Multiple Myeloma.

Multiple Myeloma (MM) is a B cell malignancy marked by genomic instability that arises both through pathogenesis and during disease progression. Despite recent advances in therapy, MM remains incurable. Recently, it has been reported that DNA repair can influence genomic changes and drug resistance in MM. The dysregulation of DNA repair function may provide an alternative explanation for genomic instability observed in MM cells and in cells derived from MM patients. This review provides an overview of DNA repair pathways with a special focus on their involvement in MM and discusses the role they play in MM progression and drug resistance. This review highlights how unrepaired DNA damage due to aberrant DNA repair response in MM exacerbates genomic instability and chromosomal abnormalities, enabling MM progression and drug resistance.

Association Between the Prevalence of Schistosomiasis in Elementary School Students and Their Parental Occupation in Sudan.

Global efforts to identify groups at high risk for schistosomiasis have mainly concentrated on identifying their geographical distribution. Investigations on the socioeconomic characteristics of high-risk groups are relatively scarce. This study aimed to explore the associations between schistosomiasis among students and their parents' occupations. A nationwide cross-sectional survey was conducted targeting 105,167 students in 1,772 primary schools across Sudan in 2017. From these students, 100,726 urine and 96,634 stool samples were collected to test for Schistosoma haematobium and S. mansoni infection. A multi-level mixed effect analysis was used with age and sex as fixed factors, and school as a random factor. The odd ratios (ORs) of practicing open defecation among farmers' children were almost 5 times higher than their counterparts whose parents were government officials (OR=4.97, 95% confidence intervals (CIs): 4.57-5.42, P<0.001). The ORs of contacting water bodies for watering livestock among farmers' children were more than 4 times higher than those of children whose parents were government officials (OR=4.59, 95% CIs: 4.02-5.24, P<0.001). This study shows that schistosomiasis represents a disease of poverty and that farmers' children constituted a high-risk group.

The Role of Polycomb Group Protein BMI1 in DNA Repair and Genomic Stability.

The polycomb group (PcG) proteins are a class of transcriptional repressors that mediate gene silencing through histone post-translational modifications. They are involved in the maintenance of stem cell self-renewal and proliferation, processes that are often dysregulated in cancer. Apart from their canonical functions in epigenetic gene silencing, several studies have uncovered a function for PcG proteins in DNA damage signaling and repair. In particular, members of the poly-comb group complexes (PRC) 1 and 2 have been shown to recruit to sites of DNA damage and mediate DNA double-strand break repair. Here, we review current understanding of the PRCs and their roles in cancer development. We then focus on the PRC1 member BMI1, discussing the current state of knowledge of its role in DNA repair and genome integrity, and outline how it can be targeted pharmacologically.

Synthesis, Antibacterial, and Antioxidant Evaluation of Novel Series of Condensed Thiazoloquinazoline with Pyrido, Pyrano, and Benzol Moieties as Five- and Six-Membered Heterocycle Derivatives.

A novel synthesis of thiazolo[2,3-b]quinazolines 4(a-e), pyrido[2',3':4,5]thiazolo[2,3-b]quinazolines {5(a-e), 6(a-e), and 7(a-e)}, pyrano[2',3':4,5]thiazolo[2,3-b]quinazolines 8(a-e), and benzo[4,5]thiazolo[2,3-b]quinazoloine9(a-e) derivatives starting from 2-(Bis-methylsulfanyl-methylene)-5,5-dimethyl-cyclohexane-1,3-dione 2 as efficient α,α dioxoketen dithioacetal is reported and the synthetic approaches of these types of compounds will provide an innovative molecular framework to the designing of new active heterocyclic compounds. In our study, we also present optimization of the synthetic method along with a biological evaluation of these newly synthesized compounds as antioxidants and antibacterial agents against the bacterial strains, like S. aureus, E. coli, and P. aeruginosa. Among all the evaluated compounds, it was found that some showed significant antioxidant activity at 10 µg/mL while the others exhibited better antibacterial activity at 100 µg/mL. The results of this study showed that compound 6(c) possessed remarkable antibacterial activity, whereas compound 9(c) exhibited the highest efficacy as an antioxidant. The structures of the new synthetic compounds were elucidated by elemental analysis, IR, 1H-NMR, and 13C-NMR.

Population Dynamics of Intermediate-Host Snails in the White Nile River, Sudan: A Year-Round Observational Descriptive Study.

We aimed to explore the population dynamics of snail in 3 sites of the White Nile in Sudan. More specifically, we aimed to investigate the annual patterns of snail populations that act as intermediate hosts of schistosomes and monthly snail infection rates and ecological characteristics presumably related to snail populations. We collected snails for 1 year monthly at 3 different shore sites in the vicinity of El Shajara along the White Nile river in Khartoum State, Sudan. In addition, we measured air and water temperatures, water turbidities, vegetation coverages, and water depths and current speeds. Most of the collected snails were Biomphalaria pfeifferi and Bulinus truncatus. The population densities of snails and their infection rates varied across survey sites. The collected snails liberated S. mansoni and S. haematobium cercariae as well as Amphistome and Echinostome cercariae. Infected snails were found during March-June. The ecological characteristics found to be associated with the absence of snails population were: high turbidity, deep water, low vegetation coverage (near absence of vegetation), high water temperature, and high current speed. To our knowledge, this is the first longitudinal study of the snail population and ecological characteristics in the main basin of the White Nile river.

Malaria and COVID-19: unmasking their ties.

The incidence and mortality of COVID-19, according to the World Health Organization reports, shows a noticeable difference between North America, Western Europe, and South Asia on one hand and most African countries on the other hand, especially the malaria-endemic countries. Although this observation could be attributed to limited testing capacity, mitigation tools adopted and cultural habits, many theories have been postulated to explain this difference in prevalence and mortality. Because death tends to occur more in elders, both the role of demography, and how the age structure of a population may contribute to the difference in mortality rate between countries were discussed. The variable distribution of the ACEI/D and the ACE2 (C1173T substitution) polymorphisms has been postulated to explain this variable prevalence. Up-to-date data regarding the role of hydroxychloroquine (HCQ) and chloroquine (CQ) in COVID-19 have been summarized. The article also sheds lights on how the similarity of malaria and COVID-19 symptoms can lead to misdiagnosis of one disease for the other or overlooking the possibility of co-infection. As the COVID-19 pandemic threatens the delivery of malaria services, such as the distribution of insecticide-treated nets (ITNs), indoor residual spraying, as well as malaria chemoprevention there is an urgent need for rapid and effective responses to avoid malaria outbreaks.

Bioassay-Guided Different Extraction Techniques of Carica papaya (Linn.) Leaves on In Vitro Wound-Healing Activities.

Herbal plants are traditionally utilized to treat various illnesses. They contain phytochemicals that can be extracted using conventional methods such as maceration, soxhlet, and boiling, as well as non-conventional methods including ultrasonic, microwave, and others. Carica papaya leaves have been used for the treatment of dengue, fungal, and bacterial infections as well as an ingredient in anti-aging products. Phytochemicals analysis detected the presence of kaempferol, myricetin, carpaine, pseudocarpaine, dehydrocarpaine I and II, ferulic acid, caffeic acid, chlorogenic acid, ß-carotene, lycopene, and anthraquinones glycoside. Conventional preparation by boiling and simple maceration is practical, simple, and safe; however, only polar phytochemicals are extracted. The present study aims to investigate the effects of three different non-conventional extraction techniques (ultrasonic-assisted extraction, reflux, and agitation) on C. papaya phytochemical constituents, the antioxidant capacity, and wound-healing activities. Among the three techniques, the reflux technique produced the highest extraction yield (17.86%) with the presence of saponins, flavonoids, coumarins, alkaloids, and phenolic metabolites. The reflux technique also produced the highest 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging with an IC50 value of 0.236 mg/mL followed by ultrasonic-assisted extraction (UAE) (IC50: 0.377 mg/mL) and agitation (IC50: 0.404 mg/mL). At tested concentrations (3.125 µg/mL to 500 µg/mL), all extracts do not exhibit a cytotoxicity effect on the human skin fibroblast, HSF1184. Interestingly, reflux and UAE were active fibroblast proliferators that support 85% (12.5 µg/mL) and 41% (6.25 µg/mL) better cell growth, respectively. Additionally, during the early 24 h of the scratch assay, the migration rate at 12.5 µg/mL was faster for all extracts with 51.8% (reflux), 49.3% (agitation), and 42.5% (UAE) as compared to control (21.87%). At 48 h, proliferated cells covered 78.7% of the scratch area for reflux extract, 63.1% for UAE, 61% for agitation, and 42.6% for control. Additionally, the collagen synthesis was enhanced for 31.6% and 65% after 24 and 48 h of treatment for reflux. An HPLC-MS/MS-QTOF (quadruple time-of-flight) analysis of reflux identified nine phytochemicals, including carpaine, kaempferol 3-(2G-glucosylrutinoside), kaempferol 3-(2″-rhamnosylgalactoside), 7-rhamnoside, kaempferol 3-rhamnosyl-(1->2)-galactoside-7-rhamnoside, luteolin 7-galactosyl-(1->6)-galactoside, orientin 7-O-rhamnoside, 11-hydroperoxy-12,13-epoxy-9-octadecenoic acid, palmitic amide, and 2-hexaprenyl-6-methoxyphenol. The results suggested that reflux was the best technique as compared to ultrasonic and agitation.

Comparison of the Change in the Prevalence and Intensity of Schistosoma haematobium Infection Between High and Low Prevalence Areas of White Nile State, Sudan.

This study aimed to investigate whether mass drug administration (MDA) intervention has an equivalent effect on reducing the prevalence and intensity of Schistosoma haematobium infection regardless of the baseline values. A repeated cross-sectional survey was performed targeting students of 12 primary schools in Al Jabalain and El Salam districts of White Nile State, Sudan, at both 1 week before and 8 months after the MDA. Prior to the baseline survey, school-aged children in Al Jabalain had received MDA interventions twice in 4 years, while those in El Salam had not. The baseline prevalence was 9.1% in Al Jabalain and 35.2% in El Salam, which were reduced to 1.8% and 5.5% at 8 months after the MDA, respectively. The corresponding reduction rates were 80.3% and 84.4%, not significant difference between both districts. However, changes in the geometric mean intensity (GMI) of egg counts were significantly different between both districts. The baseline GMIs were 14.5 eggs per 10 ml of urine (EP10) in Al Jabalain and 18.5 EP10 in El Salam, which were reduced to 7.1 and 11.2 EP10 after treatment, respectively. The corresponding reduction rates were 51.0% and 39.5%. In conclusion, MDA interventions were found to bring about similar relative reduction in prevalence regardless of the baseline value; however, the relative reduction in infection intensity was more salient in the district with a low baseline value for both prevalence and intensity. This clearly points to the importance of repeated MDA interventions in endemic areas, which will eventually contribute to schistosomiasis elimination.

Optimization of Ultrasound-Assisted Extraction Conditions Followed by Solid Phase Extraction Fractionation from Orthosiphon stamineus Benth (Lamiace) Leaves for Antiproliferative Effect on Prostate Cancer Cells.

Primarily, optimization of ultrasonic-assisted extraction (UAE) conditions of Orthospihon stamineus was evaluated and verified using a central composite design (CCD) based on three factors including extraction time (minutes), ultrasound amplitude (A), and solvent concentration (%). The response surface methodology (RSM) was performed to develop an extraction method with maximum yield and high rosmarinic acid content. The optimal UAE conditions were as follows: extraction time 21 min, ultrasound amplitudes 62 A, and solvent composition 70% ethanol in water. The crude extract was further fractionated using solid-phase extraction (SPE), where six sequential fractions that varied in polarity (0-100% Acetonitrile in water) were obtained. Next, the six fractions were evaluated for their antioxidant and anti-cancer properties. This study found that Fraction 2 (F2) contained the highest rosmarinic acid content and showed the strongest antioxidant activity. Additionally, F2 showed an anti-proliferative effect against prostate cancer (DU145) with no harmful effect on normal cells.

Correction to: An evidence-based review of the genotoxic and reproductive effects of sulfur mustard.

This is with reference to the note of the Editor-in-Chief of the Archives of Toxicology.

In Silico and In Vitro Study of the Bromelain-Phytochemical Complex Inhibition of Phospholipase A2 (Pla2).

Phospholipase A2 (Pla2) is an enzyme that induces inflammation, making Pla2 activity an effective approach to reduce inflammation. Therefore, investigating natural compounds for this Pla2 inhibitory activity has important therapeutic potential. The objective of this study was to investigate the potential in bromelain-phytochemical complex inhibitors via a combination of in silico and in vitro methods. Bromelain-amenthoflavone displays antagonistic effects on Pla2. Bromelian-asiaticoside and bromelain-diosgenin displayed synergistic effects at high concentrations of the combined compounds, with inhibition percentages of more than 70% and 90%, respectively, and antagonistic effects at low concentrations. The synergistic effect of the bromelain-asiaticoside and bromelain-diosgenin combinations represents a new application in treating inflammation. These findings not only provide significant quantitative data, but also provide an insight on valuable implications for the combined use of bromelain with asiaticoside and diosgenin in treating inflammation, and may help researchers develop more natural bioactive compounds in daily foods as anti-inflammatory agent.

Modulated Gene Expression of Toxoplasma gondii Infected Retinal Pigment Epithelial Cell Line (ARPE-19) via PI3K/Akt or mTOR Signal Pathway.

Due to the critical location and physiological activities of the retinal pigment epithelial (RPE) cell, it is constantly subjected to contact with various infectious agents and inflammatory mediators. However, little is known about the signaling events in RPE involved in Toxoplasma gondii infection and development. The aim of the study is to screen the host mRNA transcriptional change of 3 inflammation-related gene categories, PI3K/Akt pathway regulatory components, blood vessel development factors and ROS regulators, to prove that PI3K/Akt or mTOR signaling pathway play an essential role in regulating the selected inflammation-related genes. The selected genes include PH domain and leucine- rich-repeat protein phosphatases (PHLPP), casein kinase2 (CK2), vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), glutamate-cysteine ligase (GCL), glutathione S-transferase (GST), and NAD(P)H: quinone oxidoreductase (NQO1). Using reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), we found that T. gondii up-regulates PHLPP2, CK2ß, VEGF, GCL, GST, and NQO1 gene expression levels, but down-regulates PHLPP1 and PEDF mRNA transcription levels. PI3K inhibition and mTOR inhibition by specific inhibitors showed that most of these host gene expression patterns were due to activation of PI3K/Akt or mTOR pathways with some exceptional cases. Taken together, our results reveal a new molecular mechanism of these gene expression change dependent on PI3K/Akt or mTOR pathways and highlight more systematical insight of how an intracellular T. gondii can manipulate host genes to avoid host defense.

An evidence-based review of the genotoxic and reproductive effects of sulfur mustard.

Sulfur mustard (SM) is a chemical warfare agent which is cytotoxic in nature, and at the molecular level, SM acts as DNA alkylating agent leading to genotoxic and reproductive effects. Mostly, the exposed areas of the body are the main targets for SM; however, it also adversely affects various tissues of the body and ultimately exhibits long-term complications including genotoxic and reproductive effects, even in the next generations. The effect of SM on reproductive system is the reason behind male infertility. The chronic genotoxic and reproductive complications of SM have been observed in the next generation, such as reproductive hormones disturbances, testicular atrophy, deficiency of sperm cells, retarded growth of sperm and male infertility. SM exerts toxic effects through various mechanisms causing reproductive dysfunction. The key mechanisms include DNA alkylation, production of reactive oxygen species (ROS) and nicotinamide adenine dinucleotide (NAD) depletion. However, the exact molecular mechanism of such long-term effects of SM is still unclear. In general, DNA damage, cell death and defects in the cell membrane are frequently observed in SM-exposed individuals. SM can activate various cellular and molecular mechanisms related to oxidative stress (OS) and inflammatory responses throughout the reproductive system, which can cause decreased spermatogenesis and impaired sperm quality via damage to tissue function and structure. Moreover, the toxic effects of SM on the reproductive system as well as the occurrence of male infertility among exposed war troopers in the late exposure phase is still uncertain. The chronic effects of SM exposure in parents can cause congenital defects in their children. In this review, we aimed to investigate chronic genotoxic and reproductive effects of SM and their molecular mechanisms in the next generations.

Nationwide cross-sectional survey of schistosomiasis and soil-transmitted helminthiasis in Sudan: study protocol.

BACKGROUND: Schistosomiasis and soil-transmitted helminthiasis (STHs) are target neglected tropical diseases (NTDs) of preventive chemotherapy, but the control and elimination of these diseases have been impeded due to resource constraints. Few reports have described study protocol to draw on when conducting a nationwide survey. We present a detailed methodological description of the integrated mapping of schistosomiasis and STHs on the basis of our experiences, hoping that this protocol can be applied to future surveys in similar settings. In addition to determining the ecological zones requiring mass drug administration interventions, we aim to provide precise estimates of the prevalence of these diseases. METHODS: A school-based cross-sectional design will be applied for the nationwide survey across Sudan. The survey is designed to cover all districts in every state. We have divided each district into 3 different ecological zones depending on proximity to bodies of water. We will employ a probability-proportional-to-size sampling method for schools and systematic sampling for student selection to provide adequate data regarding the prevalence for schistosomiasis and STHs in Sudan at the state level. A total of 108,660 students will be selected from 1811 schools across Sudan. After the survey is completed, 391 ecological zones will be mapped out. To carry out the survey, 655 staff members were recruited. The feces and urine samples are microscopically examined by the Kato-Katz method and the sediment smears for helminth eggs respectively. For quality control, a minimum of 10% of the slides will be rechecked by the federal supervisors in each state and also 5% of the smears are validated again within one day by independent supervisors. DISCUSSION: This nationwide mapping is expected to generate important epidemiological information and indicators about schistosomiasis and STHs that will be useful for monitoring and evaluating the control program. The mapping data will also be used for overviewing the status and policy formulation and updates to the control strategies. This paper, which describes a feasible and practical study protocol, is to be shared with the global health community, especially those who are planning to perform nationwide mapping of NTDs by feces or urine sampling.

Molecular mechanisms of action of styrene toxicity in blood plasma and liver.

Styrene is an aromatic colorless hydrocarbon available in liquid form and highly volatile. In its pure form, it gives a sweet smell. The primary source of exposure in the environment is from plastic materials, rubber industries, packaging materials, insulations, and fiber glass and carpet industry. Natural sources of styrene include: few metabolites in plants which are transferred through food chain. The current study was designed to evaluate styrene toxicity, including: superoxide dismutase (SOD) and protein carbonyl, oxidative stress, glucose-6-phosphatase (G6Pase), glycogen phosphorylase (GP), and phosphoenolpyruvate carboxykinase (PEPCK) activities, adenosine triphosphate (ATP) to adenosine diphosphate (ADP) ratio, and changes in gene expressions such as glutamate dehydrogenase 1 (GLUD1), glucose transporter 2 (GLUT2), and glucokinase (GCK) in the rat liver tissue. For this purpose, styrene was dissolved in corn oil and was administered via gavage, at doses 250, 500, 1000, 1500, 2000, mg/kg/day per mL and control (corn oil) to each rat with one day off in a week, for 42 days. Plasma SOD and protein carbonyl of plasma were significantly up-regulated in 1000, 1500, and 2000 mg/kg/day styrene administrated groups (P < .001). In addition, styrene caused an increase in lipid peroxidation (LPO) and reactive oxygen species (ROS) in the dose-dependent manners in liver tissue (P < .001). Furthermore, the ferrous reducing antioxidant power (FRAP) and total thiol molecules (TTM) in styrene-treated groups were significantly decreased in liver tissue (P < .001) with increasing doses. In treated rats, styrene significantly increased G6Pase activity (P < .001) and down-regulated GP activity (P < .001) as compared to the control group. The PEPCK activity was significantly raised in a dose-dependent manner (P < .001). The ATP/ADP ratio of live cells was significantly raised by increasing the dose (P < .001). There was significantly an up-regulation of GLUD1 and GCK at 2000 mg/kg group (P < .01) and a down-regulation for GLUT2 at the same dose. While in the rest of group, GLUT2 showed up-regulation of relative fold change. By targeting genes such as GLUD1, GLUT2, and GCK, disruption of hepatic gluconeogenesis, glycogenolysis, and insulin secretory functions are obvious. The present study illustrates that induction of oxidative stress followed by changes in G6Pase, GP, and PEPCK activities and the genes responsible for glucose metabolism are the mechanisms of styrene's action in the liver.

IL-12 and IL-23 Production in Toxoplasma gondii- or LPS-Treated Jurkat T Cells via PI3K and MAPK Signaling Pathways.

IL-12 and IL-23 are closely related in structure, and have been shown to play crucial roles in regulation of immune responses. However, little is known about the regulation of these cytokines in T cells. Here, we investigated the roles of PI3K and MAPK pathways in IL-12 and IL-23 production in human Jurkat T cells in response to Toxoplasma gondii and LPS. IL-12 and IL-23 production was significantly increased in T cells after stimulation with T. gondii or LPS. T. gondii and LPS increased the phosphorylation of AKT, ERK1/2, p38 MAPK, and JNK1/2 in T cells from 10 min post-stimulation, and peaked at 30-60 min. Inhibition of the PI3K pathway reduced IL-12 and IL-23 production in T. gondii-infected cells, but increased in LPS-stimulated cells. IL-12 and IL-23 production was significantly reduced by ERK1/2 and p38 MAPK inhibitors in T. gondii- and LPS-stimulated cells, but not in cells treated with a JNK1/2 inhibitor. Collectively, IL-12 and IL-23 production was positively regulated by PI3K and JNK1/2 in T. gondii-infected Jurkat cells, but negatively regulated in LPS-stimulated cells. And ERK1/2 and p38 MAPK positively regulated IL-12 and IL-23 production in Jurkat T cells. These data indicate that T. gondii and LPS induced IL-12 and IL-23 production in Jurkat T cells through the regulation of the PI3K and MAPK pathways; however, the mechanism underlying the stimulation of IL-12 and IL-23 production by T. gondii in Jurkat T cells is different from that of LPS.

Genetic Diversity of Schistosoma haematobium Eggs Isolated from Human Urine in Sudan.

The genetic diversity of Schistosoma haematobium remains largely unstudied in comparison to that of Schistosoma mansoni. To characterize the extent of genetic diversity in S. haematobium among its definitive host (humans), we collected S. haematobium eggs from the urine of 73 infected schoolchildren at 5 primary schools in White Nile State, Sudan, and then performed a randomly amplified polymorphic DNA marker ITS2 by PCR-RFLP analysis. Among 73 S. haematobium egg-positive cases, 13 were selected based on the presence of the S. haematobium satellite markers A4 and B2 in their genomic DNA, and used for RFLP analysis. The 13 samples were subjected to an RFLP analysis of the S. haematobium ITS2 region; however, there was no variation in size among the fragments. Compared to the ITS2 sequences obtained for S. haematobium from Kenya, the nucleotide sequences of the ITS2 regions of S. haematobium from 4 areas in Sudan were consistent with those from Kenya (> 99%). In this study, we demonstrate for the first time that most of the S. haematobium population in Sudan consists of a pan-African S. haematobium genotype; however, we also report the discovery of Kenyan strain inflow into White Nile, Sudan.