Dual anticancer and antibacterial activity of fluorescent naphthoimidazolium salts

Cancer has emerged as a significant global health challenge, ranking as the second leading cause of death worldwide. Moreover, cancer patients frequently experience compromised immune systems, rendering them susceptible to bacterial infections. Combining anticancer and antibacterial properties in a single drug could lead to improved overall treatment outcomes and patient well-being. In this context, the present study focused on a series of hydrophilic naphthoimidazolium salts with donor groups (NI-R), aiming to create dual-functional agents with antibacterial and anticancer activities. Among these compounds, NI-TPA demonstrated notable antibacterial activity, particularly against drug-resistant bacteria, with MIC value of 7.8 μg mL-1. Furthermore, NI-TPA exhibited the most potent cytotoxicity against four different cancer cell lines, with an IC50 range of 0.67-2.01 μg mL-1. The observed high cytotoxicity of NI-TPA agreed with molecular docking and dynamic simulation studies targeting c-Met kinase protein. Additionally, NI-TPA stood out as the most promising candidate for two-photo excitation, fluorescence bioimaging, and localization in lysosomes. The study findings open new avenues for the design and development of imidazolium salts that could be employed in phototheranostic applications for cancer treatment and bacterial infections.

Imidazolium-Based Heavy-Atom-Free Photosensitizer for Nucleus-Targeted Fluorescence Bioimaging and Photodynamic Therapy

The development of heavy-atom-free photosensitizers (PSs) for photodynamic therapy (PDT) has encountered significant challenges in achieving simultaneous high fluorescence emission and reactive oxygen species (ROS) generation. Moreover, the limited water solubility of these PSs imposes further limitations on their biomedical applications. To overcome these obstacles, this study presents a molecular design strategy employing hydrophilic heavy-atom-free PSs based on imidazolium salts. The photophysical properties of these PSs were comprehensively investigated through a combination of experimental and theoretical analyses. Notably, among the synthesized PSs, the ethylcarbazole-naphthoimidazolium (NI-Cz) conjugate exhibited efficient fluorescence emission (ΦF = 0.22) and generation of singlet oxygen (ΦΔ = 0.49), even in highly aqueous environments. The performance of NI-Cz was validated through its application in fluorescence bioimaging and PDT treatment in HeLa cells. Furthermore, NI-Cz holds promise for two-photon excitation and type I ROS generation, nucleus localization, and selective activity against Gram-positive bacteria, thereby expanding its scope for the design of heavy-atom-free PSs and phototheranostic applications.

Initial phase establishment of an in vitro method for developmental neurotoxicity test using Ki-67 in human neural progenitor cells

Building a precise alternative neurotoxicological test is of great importance to respond to societal and ethical requirements. In this study, a new developmental neurotoxicity test (DNT) was established with the human neural progenitor cell line. ReNcell CX cells were exposed to neurotoxic chemicals (aphidicolin, hydroxyurea, cytosine arabinoside, 5-fluorouracil, and ochratoxin A) or non-neurotoxic chemicals (sodium gluconate, sodium bicarbonate, penicillin G, and saccharin). Propidium iodide (PI) was used to evaluate cell viability. BrdU and Ki-76 were employed to determine cell proliferation. Based on the cell viability and proliferation, mathematical models were built by linear discriminant analysis. Furthermore, the neurotoxic-considered chemicals inhibited cell cycle progression at the protein level, supporting the biomolecular rationale for the predictive model. Overall, these results show that the new test method can be used to determine the potential developmental neurotoxicants or new drug candidates.

LMP1-EBV Gene Deletion Mutations and HLA Genotypes of Nasopharyngeal Cancer Patients in Vietnam

Nasopharyngeal carcinoma (NPC) is the most common cancer among head and neck cancers in Vietnam. We aimed to identify the rate of a 30 bp deletion mutation of the LMP1-EBV gene in nasopharyngeal biopsy tissue samples, the HLA genotypes of NPC patients, and the relationship between these two targets. Patients with NPC at Can Tho Oncology Hospital from September 2014 to December 2018 were selected. A length of 30 bp of the del-LMP1-EBV gene was analyzed using a PCR technique, and the HLA genotypes in patients' blood samples were analyzed with PCR-SSO technology. HLA-B*15 gene carriers had the highest risk of 30 bp LMP1-EBV gene deletion mutation, which was found in 51 out of 70 patients (72.9%). Carriers of the HLA-B*15 allele had a 4.6-fold increased risk of a 30 bp del-LMP1-EBV gene compared with non-carriers of this allele. The initial identification of NPC was related to the 30 bp del-LMP1-EBV gene and high frequencies of the -A*02, -B*15, -DRB1*12, -DQB1*03, and -DQA1*01 HLA alleles. Our study results suggest an association of the 30 bp del-LMP1-EBV gene and the HLA-B*15 allele with NPC susceptibility.

Potassium-dependent sodium/calcium exchanger 3 (Nckx3) depletion leads to abnormal motor function and social behavior in mice

Transcellular calcium transport is an essential activity in mineralized tissue formation, including that in nervous systems. Dysregulation of Ca²⁺ homeostasis can induce excitotoxicity and neurodegeneration in the central nervous system. Nckx3, a potassium-dependent Na⁺/Ca²⁺ exchanger, is most abundant in the brain and has a critical role in the transport of intracellular calcium across the cell membrane. However, the roles of Nckx3 in neuron development and function remain unreported. Herein, we examined the behaviors of Nckx3-knock-out mice at the age of six weeks. Detailed behavioral analyses showed Nckx3^-/- mice exhibited an increase in moving distances in the open field test. Additionally, the rotarod test revealed motor learning defects in Nckx3^-/- mice. Both Nckx3^+/- and Nckx^-/- mice also exhibited deficits in sociability and social novelty preference. Furthermore, Nckx^-/- mice displayed increased depression-related behavior. However, there was no significant change in cognition function detected in Nckx^-/- mice. This study demonstrates that NCKX3 is involved in behavior and neuronal function.

Cigarette smoke extraxt influences intracellular calcium concentration in A549 cells

Cigarette smoking is a major risk factor for pulmonary diseases, including chronic obstructive pulmonary disease (COPD) and cancer. Cigarette smoke is reported to contain over 4,000 chemical compounds. Therefore, it needs to study the effects of cigarette smoke extract (CSE) administration on intracellular calcium concentration. In this study, we investigated how CSE influences intracellular calcium concentration in human lung adenocarcinoma A549 cells. The CSE concentrations used (0.4, 2, 3%) did not influence cell viability. However, at these CSE concentrations, calcium influx transient receptor potential vanilloid 4 (TRPV4) and transient receptor potential vanilloid 6 (TRPV6) proteins significantly increased, whereas calcium efflux sodium-calcium exchanger (NCX1) and plasma membrane Ca2+ ATPase (PMCA1) proteins significantly decreased from those of the control cells. The 3% CSE treatment produced an intracellular calcium concentration higher than that of the control treatment through methods of co-transfection of pGP-CMV-GCaMP6f/CMV-R-GECO1.2 and Rhod-4 Assay. CSE induced concentration-dependent increments in hypoxia-inducible factor (HIF)-1α and HIF-2α protein levels. Moreover, phosphorylation of ERK and Akt was induced by CSE treatment. Also, mitochondrial marker B-cell lymphoma 2 (Bcl-2) protein level decreased and Bcl-2-associated X (Bax) protein level increased following CSE treatment. Also, endoplasmic reticulum (ER) stress markers BiP, CHOP, p-SAPK, and p-eIF2α levels were increased by CSE treatment. These results suggest that CSE may increase the concentration of intracellular calcium, thus increasing mitochondrial and ER stress.

Evaluation of the expression levels of BRAFV600E mRNA in primary tumors of thyroid cancer using an ultrasensitive mutation assay

Background

The BRAF^V600E gene encodes for the mutant BRAF^V600E protein, which triggers downstream oncogenic signaling in thyroid cancer. Since most currently available methods have focused on detecting BRAF^V600E mutations in tumor DNA, there is limited information about the level of BRAF^V600E mRNA in primary tumors of thyroid cancer, and the diagnostic relevance of these RNA mutations is not known.

Methods

Sixty-two patients with thyroid cancer and non-malignant thyroid disease were included in the study. Armed with an ultrasensitive technique for mRNA-based mutation analysis based on a two step RT-qPCR method, we analysed the expression levels of the mutated BRAF^V600E mRNA in formalin-fixed paraffin-embedded samples of thyroid tissues. Sanger sequencing for detection of BRAF^V600E DNA was performed in parallel for comparison and normalization of BRAF^V600E mRNA expression levels.

Results

The mRNA-based mutation detection assay enables detection of the BRAF^V600E mRNA transcripts in a 10,000-fold excess of wildtype BRAF counterparts. While BRAF^V600E mutations could be detected by Sanger sequencing in 13 out of 32 malignant thyroid cancer FFPE tissue samples, the mRNA-based assay detected mutations in additionally 5 cases, improving the detection rate from 40.6 to 56.3%. Furthermore, we observed a surprisingly large, 3-log variability, in the expression level of the BRAF^V600E mRNA in FFPE samples of thyroid cancer tissue.

Conclusions

The expression levels of BRAF^V600E mRNA was characterized in the primary tumors of thyroid cancer using an ultrasensitive mRNA-based mutation assay. Our data inspires further studies on the prognostic and diagnostic relevance of the BRAF^V600E mRNA levels as a molecular biomarker for the diagnosis and monitoring of various genetic and malignant diseases.

Progress towards rabies control and elimination in Vietnam

Rabies is a fatal viral disease that causes an estimated 59,000 human deaths each year. The majority of these deaths occur in developing countries in Asia. Canine rabies is endemic to Vietnam, which is, however, moving towards the disease's elimination. Many countries, such as Vietnam, have invested tremendous resources in controlling rabies, highlighting the goal of regional and global elimination of this neglected disease. In Vietnam, rabies is recognised as one of five high-priority, zoonotic diseases by the Ministry of Health and the Ministry of Agriculture and Rural Development. Investment by the government and by international partners for rabies prevention and control has played a substantial role in reducing human rabies deaths from 404 cases in 1992 to 74 cases in 2017. The catalyst for this effort was the Prime Minister's creation of the National Rabies Program in 1996, which led to increased support and resources for rabies prevention and control. Interventions carried out since then include the expansion of post-exposure prophylaxis centres throughout the country, the introduction or revision of key legislation and guidelines, and improved multisectoral One Health collaboration. In addition, support from international partners, such as the World Organisation for Animal Health (OIE), the World Health Organization (WHO), the Food and Agriculture Organization of the United Nations (FAO), and the Centers for Disease Control and Prevention (CDC), has helped to increase awareness, manage dog populations more effectively, and improve Vietnam's surveillance and diagnostic capabilities. To pursue the goal of eliminating dog-mediated rabies in Vietnam, political commitment is crucial. Resources must be made available to enforce the regulations and guidelines that will enable Vietnam to achieve greater canine rabies vaccination coverage. In this paper, the authors provide an overview of the animal and human health systems in Vietnam, as well as past, current and future directions of rabies prevention and control.

DNA-HPV transition rate and related factors in HPV-infected women in Can Tho city, Vietnam

OBJECTIVES

To determine DNA-HPV transition rates and related factors in HPV-infected women 18-69 years of age in Can Tho City from 2013 to 2018.

METHODS

Both a retrospective and a prospective cohort study were done. Interviews, gynaecological examinations and HPV testing by PCR (cervical fluid) were used to collect data. The results were recorded and compared with those of HPV in 2013 to assess the development of HPV over time. Transition was defined as conversion to HPV-positive state in 2018 from a negative state in 2013. No transition was defined as clearance of HPV when the positive 2013 result was negative in 2018 or when the result remained negative or positive in 2013 and 2018. Factors related to the change were analysed.

RESULTS

Among a sample size of 204 cases, the average age of participants was 48.9 ± 10.4 years. Women >45 comprised 63.2% of participants; 82.8% lived with their husbands, 6.4% were divorced, and 2.9% lived apart from their husbands due to work. After 5 years of observation, 16.2% of DNA-HPV cases had converted to HPV-positive state and 66.2% of DNA-HPV cases had cleared to HPV-negative state. Factors related to conversion to HPV-positive state were age ≤ 45 years (3.14 times higher risk of transition than in the >45 age group (95% CI: 1.12-8.8)); change of sexual partner (OR = 3.75 (95% CI: 1.15-12.2)); change of sexual partner by husband (OR = 3.69 (95% CI: 1.20-11.3); sexually transmitted diseases (OR = 5.19 (95% CI: 1.09-24.8)); and a history of vacuum aspiration or dilation and evacuation abortion (OR = 1.4 (95% CI: 0.29-6.4)).

CONCLUSIONS

16.2% of women with DNA-HPV transition converted to HPV-positive state. Changes in sexual habits increase the risk of developing HPV positivity.

Emergence of New Delhi metallo-beta-lactamase 1 and other carbapenemase-producing Acinetobacter calcoaceticus-baumannii complex among patients in hospitals in Ha Noi, Viet Nam

Acinetobacter baumannii is an important cause of multidrug-resistant hospital acquired infections in the world. Here, we investigate the presence of NDM-1 and other carbapenemases among carbapenem-resistant A. baumannii isolated between August 2010 and December 2014 from three large hospitals in Hanoi, Vietnam. We identified 23/582 isolates (4 %) (11 from hospital A, five from hospital B, and seven from hospital C) that were NDM-1 positive, and among them 18 carried additional carbapenemase genes, including seven isolates carrying NDM-1, IMP-1, and OXA-58 with high MICs for carbapenems. Genotyping indicated that NDM-1 carrying A. baumannii have expanded clonally in these hospitals. Five new STs (ST1135, ST1136, ST1137, ST1138, and ST1139) were identified. One isolate carried NDM-1 on a plasmid belonging to the N-repA replicon type; no NDM-1-positive plasmids were identified in the other isolates. We have shown the extent of the carbapenem resistance and the local clonal spread of A. baumannii carrying NDM-1 in these hospitals; coexistence of NDM-1 and IMP-1 is reported for the first time from Vietnam here, and this will further seriously limit future therapeutic options.

Common isolation of New Delhi metallo-beta-lactamase 1-producing Enterobacteriaceae in a large surgical hospital in Vietnam

This study sought to monitor the presence of carbapenem-resistant Enterobacteriaceae (CRE) and the proportion New Delhi metallo-beta-lactamase 1 (NDM-1)-producing bacteria between August 2010 and December 2012 in a surgical hospital in Vietnam. We identified 47 CRE strains from a total of 4,096 Enterobacteriaceae isolates (1.1 %) that were NDM-1-positive from 45 patients admitted to 11 different departments, with the majority being from the urology department. The NDM-1 gene was found in seven different species. Genotyping revealed limited clonality of NDM-1-positive isolates. Most of the isolates carried the NDM-1 gene on a plasmid and 17.8 % (8/45) of those were readily transferable. We found five patients at admission and one patient at discharge with NDM-1-positive bacteria in their stool. From 200 screening environmental hospital samples, five were confirmed to be NDM-1-positive and included Acinetobacter species (n = 3) and Enterobacter aerogenes (n = 2). The results reveal that NDM-1-producing Enterobacteriaceae are commonly isolated in patients admitted to a Vietnamese surgical hospital and are also detected in the hospital environment.

Applying the transtheoretical model to cervical cancer screening in Vietnamese-American women

BACKGROUND

Low levels of Papanicolaou (Pap) screening participation in Vietnamese-American women remain a significant public health problem. The transtheoretical model (TTM) suggests that individuals adopting Pap smear behaviour move through a series of stages of readiness to change. Determining a woman's level of readiness for regular Pap testing and identifying the screening behaviour that an individual already performs is important in the development of successful intervention programmes that address the specific needs of Vietnamese-American women in different stages.

AIMS

To describe Pap smear screening behaviours of Vietnamese-American women, and to examine whether constructs (stages of change, self-efficacy and perceived benefits/barriers) from the TTM are applicable to Vietnamese-American women relative to Pap testing.

METHODS

A descriptive, cross-sectional design with snowball sampling was used to recruit participants. A total of 80 Vietnamese-American women completed the self-administered questionnaire.

RESULTS

Most respondents (62.5%) reported previous Pap testing and only 46.3% receiving regular Pap testing. Compared with those in the pre-contemplation stage of the TTM, participants in maintenance reported significantly less self-efficacy (F (3, 73) = 4.85, P = 0.00), a lower level of perceived barriers (F (3, 75) = 5.99, P = 0.00) and a higher level of perceived benefits (F (3, 76) = 3.91, P = 0.01) relative to Pap smear.

CONCLUSIONS

The results support some of the assumptions of the TTM but raise questions about the predicted relationships between stages of change and self-efficacy. Continued research is needed to identify the most effective theory-based interventions for evidence-based nursing practice in this population.

Mapping the determinants of the CCR5 amino-terminal sulfopeptide interaction with soluble human immunodeficiency virus type 1 gp120-CD4 complexes

CD4 and CCR5 mediate fusion and entry of R5 human immunodeficiency virus type 1 (HIV-1) strains. Sulfotyrosine and other negatively charged residues in the CCR5 amino-terminal domain (Nt) are crucial for gp120 binding and viral entry. We previously showed that a soluble gp120-CD4 complex specifically binds to a peptide corresponding to CCR5 Nt residues 2 to 18, with sulfotyrosines in positions 10 and 14. This sulfopeptide also inhibits soluble gp120-CD4 binding to cell surface CCR5 as well as infection by an R5 virus. Here we show that residues 10 to 18 constitute the minimal domain of the CCR5 Nt that is able to specifically interact with soluble gp120-CD4 complexes. In addition to sulfotyrosines in positions 10 and 14, negatively charged residues in positions 11 and 18 participate in this interaction. Furthermore, the CCR5 Nt binds to a CD4-induced surface on gp120 that is composed of conserved residues in the V3 loop stem and the C4 domain. Binding of gp120 to cell surface CCR5 is further influenced by residues in the crown of the V3 loop, C1, C2, and C3. Our data suggest that gp120 docking to CCR5 is a multistep process involving several independent regions of the envelope glycoprotein and the coreceptor.

Single-dose safety, pharmacology, and antiviral activity of the human immunodeficiency virus (HIV) type 1 entry inhibitor PRO 542 in HIV-infected adults

PRO 542 (CD4-IgG2) is a recombinant antibody-like fusion protein wherein the Fv portions of both the heavy and light chains of human IgG2 have been replaced with the D1D2 domains of human CD4. Unlike monovalent and divalent CD4-based proteins, tetravalent PRO 542 potently neutralizes diverse primary human immunodeficiency virus (HIV) type 1 isolates. In this phase 1 study, the first evaluation of this compound in humans, HIV-infected adults were treated with a single intravenous infusion of PRO 542 at doses of 0.2-10 mg/kg. PRO 542 was well tolerated, and no dose-limiting toxicities were identified. Area under the concentration-time curve, and peak serum concentrations increased linearly with dose, and a terminal serum half-life of 3-4 days was observed. No patient developed antibodies to PRO 542. Preliminary evidence of antiviral activity was observed as reductions in both plasma HIV RNA and plasma viremia. Sustained antiviral effects may be achieved with repeat dosing with PRO 542.

Differential inhibition of human immunodeficiency virus type 1 fusion, gp120 binding, and CC-chemokine activity by monoclonal antibodies to CCR5

The CC-chemokine receptor CCR5 mediates fusion and entry of the most commonly transmitted human immunodeficiency virus type 1 (HIV-1) strains. We have isolated six new anti-CCR5 murine monoclonal antibodies (MAbs), designated PA8, PA9, PA10, PA11, PA12, and PA14. A panel of CCR5 alanine point mutants was used to map the epitopes of these MAbs and the previously described MAb 2D7 to specific amino acid residues in the N terminus and/or second extracellular loop regions of CCR5. This structural information was correlated with the MAbs' abilities to inhibit (i) HIV-1 entry, (ii) HIV-1 envelope glycoprotein-mediated membrane fusion, (iii) gp120 binding to CCR5, and (iv) CC-chemokine activity. Surprisingly, there was no correlation between the ability of a MAb to inhibit HIV-1 fusion-entry and its ability to inhibit either the binding of a gp120-soluble CD4 complex to CCR5 or CC-chemokine activity. MAbs PA9 to PA12, whose epitopes include residues in the CCR5 N terminus, strongly inhibited gp120 binding but only moderately inhibited HIV-1 fusion and entry and had no effect on RANTES-induced calcium mobilization. MAbs PA14 and 2D7, the most potent inhibitors of HIV-1 entry and fusion, were less effective at inhibiting gp120 binding and were variably potent at inhibiting RANTES-induced signaling. With respect to inhibiting HIV-1 entry and fusion, PA12 but not PA14 was potently synergistic when used in combination with 2D7, RANTES, and CD4-immunoglobulin G2, which inhibits HIV-1 attachment. The data support a model wherein HIV-1 entry occurs in three stages: receptor (CD4) binding, coreceptor (CCR5) binding, and coreceptor-mediated membrane fusion. The antibodies described will be useful for further dissecting these events.

Involvement of angiotensin receptor subtypes in osmotically induced release of vasopressin

We have previously shown that AT1 and AT2 angiotensin II (Ang II) receptors mediate the release of arginine vasopressin (AVP) to central injections of Ang II. In this study we have tested the hypothesis that Ang II, acting at AT1 and AT2 receptors in the brain, is involved in mediating osmotically stimulated AVP release. Adult Sprague-Dawley rats were fitted with intraventricular (i.v.t.) cannulas and catheters in the carotid artery and the femoral vein. Intraventricular injections of Ang II receptor antagonists specific to different subtypes of the receptor (AT1 and AT2) were given before a 30 min infusion of hypertonic (2.5 M) saline. Arterial blood samples were collected 5 min before and at two time points after (+15 min and +30 min) beginning the saline infusion. We found that both losartan (AT1 specific) and CGP42112A (AT2 specific) significantly reduced osmotically induced release of AVP. PD123319 (AT2 specific) had no effect of osmotically stimulated AVP release. A combined treatment of losartan + PD123319 was no more effective than losartan in blocking the AVP response. Since losartan was the most rapid and effective antagonist of osmotically stimulated AVP release, we conclude that AT1 receptors are directly involved in the response. However, but since CGP42112A was also an effective antagonist and since, AT2 receptors are located at sites distant from the hypothalamus, such as the locus ceruleus, they may also contribute to this response. We conclude that brain Ang II receptors are involved in osmotically stimulated AVP release.