A5085827016- Legionella and Acanthamoeba research
- Nanoplatforms for cancer theranostics
- Photodynamic Therapy Research Studies
- Heme Oxygenase-1 and Carbon Monoxide
- Neonatal Health and Biochemistry
- Vibrio bacteria research studies
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- SARS-CoV-2 and COVID-19 Research
- Luminescence Properties of Advanced Materials
- Bone Tissue Engineering Materials
- Bacteriophages and microbial interactions
- Medical and Biological Ozone Research
- Laser-Ablation Synthesis of Nanoparticles
- Microbial infections and disease research
- Vector-borne infectious diseases
- Malaria Research and Control
- Bacterial biofilms and quorum sensing
- Adipose Tissue and Metabolism
- Phonetics and Phonology Research
- Nerve injury and regeneration
- Laser Material Processing Techniques
- Photoacoustic and Ultrasonic Imaging
- Ocular and Laser Science Research
- Nanoparticles: synthesis and applications
- Voice and Speech Disorders
Western Kentucky University
2020-2024
Dr. S.R. Chandrasekhar Institute of Speech and Hearing
2023
University of Iowa
2015
Purdue University West Lafayette
2007-2011
State Street (United States)
2008-2009
Harvard University
2008
A large number of proteins transferred by the Legionella pneumophila Dot/Icm system have been identified various strategies. With no exceptions, these strategies are based on one or more characteristics associated with tested proteins. Given high level diversity exhibited proteins, it is possible that some substrates missed in screenings. In this study, we took a systematic method to survey L. genome testing hypothetical orfs larger than 300 base pairs for Dot/Icm-dependent translocation....
Legionella pneumophila is an intracellular pathogen responsible for Legionnaires' disease. This bacterium uses the Dot/Icm type IV secretion system to inject a large number of bacterial proteins into host cells facilitate biogenesis phagosome permissive its growth. Like many highly adapted intravacuolar pathogens, L. able maintain neutral pH in lumen phagosome, particularly early phase infection. However, all cases, molecular mechanisms underlying this observation remain unknown. In report,...
The intracellular bacterial pathogen Legionella pneumophila causes an inflammatory pneumonia called Legionnaires' Disease. For virulence, L. requires a Dot/Icm type IV secretion system that translocates effectors to the host cytosol. lacking is recognized by Toll-like receptors (TLRs), leading canonical NF-κB-dependent transcriptional response. In addition, expressing functional potently induces unique targets, including proinflammatory genes such as Il23a and Csf2. Here we demonstrate this...
To establish a vacuole that supports bacterial replication, Legionella pneumophila translocates large number of proteins into host cells via the Dot/Icm type IV secretion system. Functions most these translocated are unknown, but recent investigations suggest their roles in modulating diverse processes such as vesicle trafficking, autophagy, ubiquitination, and apoptosis. Cells infected by L. exhibited resistance to apoptotic stimuli, protein directly involved this process remained elusive....
Coxiella burnetii is an obligate intracellular bacterial pathogen responsible for acute and chronic Q fever. This bacterium harbors a type IV secretion system (T4SS) highly similar to the Dot/Icm of Legionella pneumophila that believed be essential its infectivity. Protein substrates T4SS are predicted facilitate biogenesis phagosome permissive growth. However, due lack genetic systems, protein transfer by C. has not been demonstrated. In this study, we report identification 32 using...
The Legionella pneumophila Dot/Icm type IV secretion system is essential for the biogenesis of a phagosome that supports bacterial multiplication, most likely via functions its protein substrates. Recent studies indicate fundamental cellular processes, such as vesicle trafficking, stress response, autophagy and cell death, are modulated by these effectors. However, how each translocated contributes to modulation pathways largely unknown. In screen search substrates transporter can cause host...
According to the World Health Organization, COVID-19 may have caused ~15-million deaths across globe and is still ravaging world. Another wave of ~100 million infections predicted in United States due emergence highly transmissible immune-escaped Omicron variants.
Efflux pumps are active transporters, which allow the cell to remove toxic substances from within including antibiotics and photosensitizer complexes. pump inhibitors (EPIs), chemicals that prevent passage of molecules through efflux pumps, play a crucial role in antimicrobial effectiveness against pathogen. In this work, we studied effect EPI, namely, reserpine, on photodeactivation rate pathogens when used with Ag NPs methylene blue (MB). Our results show using reserpine led higher...
The formation of laser-induced periodic surface structures (LIPSS) on mirror-polished 304-grade stainless steel sheets with dimensions 25 mm × 0.8 upon irradiation picosecond laser pulses in air and water environments at different wavelengths, number pulses, energy densities was investigated. Atomic force microscopy (AFM) scanning electron (SEM) were used to characterize the LIPSS. Tunable periodicity LIPSS observed both media wavelengths fluence. Fluence shown be main parameter LIPSS;...
In this study, the effects of substrate temperature and ablation wavelength/mechanism on structural, mechanical, bioactivity properties hydroxyapatite (HA) coatings were investigated. HA deposited both Si(100) Ti6Al4V surfaces. Substrate varied from room to 800 °C. Depositions performed in Ar/H2O vacuum environments. X-ray diffraction, scanning electron microscopy, atomic force microscopy techniques used analyze structural morphological variations. The adherence substrates was assessed by...
Analysis of phenotypes associated with specific mutants has been instrumental in determining the roles a bacterial gene biological process. However, this technique does not allow one to address whether or set is necessary maintain such process once it established. In study microbial pathogenesis, important but difficult determine temporal requirement essential pathogenic determinants entire infection cycle. Here we report Cre/loxP-based genetic system that allowed inducible deletion genes...
Vaccine-induced immunity depends on long-lived plasma cells (LLPCs) that maintain antibody levels. A recent mouse study showed Plasmodium chaubaudi infection reduced pre-existing influenza-specific antibodies—raising concerns malaria may compromise vaccine responses. We extended these findings to P. yoelii infection, observing decreases in antibodies model antigens inbred mice and influenza outbred mice, associated with LLPC depletion increased susceptibility rechallenge. investigated the...
This study reports the effects of substrate temperature and laser ablation wavelength on structural bioactivity properties hydroxyapatite (HAP) coatings. The coatings were obtained using a pulsed deposition technique Ti6Al4V Si(100) substrates. Different temperatures used ranging from 25°C to 800°C. Three wavelengths Nd:YAG (1064 nm, 532 355 nm) employed mechanisms their film morphology. Surface morphology was investigated by SEM with EDX Analysis AFM. All confirmed be grown in granular...
Bacterial antibiotic resistance poses a pressing global health crisis, challenging conventional therapies. Efflux pumps diminish antimicrobial effectiveness by expelling drugs from bacterial cells. Multidrug efflux (MEPs) have been found to transport diverse compounds, including phenothiazinium dyes like methylene blue, out of bacteria. Inhibition MEPs offers promising strategy bolster the efficacy photodynamic inactivation (PDT). This research adopts synergistic approach, combining pump...
Brain-derived neurotrophic factor (BDNF) is a pleiotropic neuronal growth and survival that indispensable in the brain, as well multiple other tissues organs, including cardiovascular system. In approximately 30% of general population, BDNF harbors nonsynonymous single nucleotide polymorphism may be associated with cardiometabolic disorders, coronary artery disease, Duchenne muscular dystrophy cardiomyopathy. We recently showed transgenic mice human rs6265 (Val66Met) exhibit altered cardiac...
This conference presentation was prepared for the Optical Methods Tumor Treatment and Detection: Mechanisms Techniques in Photodynamic Therapy XXXI at SPIE BiOS, Photonics West 2023.
Photosensitizing agents play an essential role in deactivation process of multidrug resistant pathogens and tumor treatments. In this work, methylene blue (MB) functionalized silver nanoparticles (Ag NPs) are used as effective photodynamic therapy (PDT) agent for deactivating different strains bacteria. Ag NPs were synthesized by pulsed laser ablation technique aqueous solutions like polyvinylpyrrolidone (PVP), citrate polyvinyl alcohol (PVA) at wavelength power. With 1064nm wavelength,...
SUMMARY The authorized mRNA- and adenovirus-based SARS-CoV-2 vaccines are intramuscularly injected effective in preventing COVID-19, but do not induce efficient mucosal immunity, or prevent viral transmission. We developed a bacteriophage T4-based, multicomponent, needle adjuvant-free, vaccine by engineering spike trimers on capsid exterior nucleocapsid protein the interior. Intranasal administration of T4-COVID induced higher virus neutralization antibody titers against multiple variants,...