Incidence and molecular characterization of extended-spectrum beta-lactamase (ESBL)-producing Salmonella enterica and Escherichia coli of avifauna origin in Pakistan.

Members of Enterobacteriaceae are known to produce extended-spectrum beta-lactamases (ESBL) which hydrolyze the beta-lactam group of antibiotics. The existence of ESBL-producing Salmonella enterica (S. enterica) and Escherichia coli (E. coli) harbored by urban avifauna was investigated in this study. Dropping samples (n= 180) were collected from six different bird species in the district Jhang, Punjab province, Pakistan. Isolation and identification of ESBL isolates were made by using cefotaxime- (4 mg/L) supplemented MacConkey agar and double disc synergy test (DDST). Polymerase chain reaction (PCR) was performed for the detection of four different ESBL genes including blaCTX-M, blaTEM, blaSHV and blaOXA. A total of 42.69% isolates were confirmed as ESBL via DDST including 30.64% S. enterica and 49.54% E. coli. The incidence of ESBL S. enterica and ESBL E. coli was found highest in egret (Ardea alba) and pigeon (Columba livia) as 64.28% and 78.95%, respectively. The blaCTX-M gene was detected in 57.89% and 64.81% of isolates of S. enterica and E. coli, respectively. Among other genes in S. enterica and E. coli, blaTEM (21.05%, 20.4%); blaSHV (15.78%, 9.26%), and blaOXA (5.26%, 5.56%) were detected, respectively. All of the tested isolates were found resistant to at least one of the thirteen antimicrobial agents except meropenem. To the best of our knowledge, this is the first study reporting the incidence and genetic diversity of ESBL bacteria associated with urban avifauna in Pakistan. The urban avifauna can serve as a potential subject of bio-surveillance to monitor the emergence of antimicrobial-resistant bacteria.

Estimation of activity concentrations of radionuclides and their hazard indices in coastal plain sand region of Ogun state.

Assessment of natural background radionuclides emanating from the subsurface geological features was carried out with the use of gamma-ray spectrometry at various locations at one of the secondary school in Canaan land, Ota, Ogun State. The activity concentrations of 226Ra, 232Th and 40K were revealed to be 12.66 ± 0.76-42.33 ± 1.37, 44.96 ± 1.41-128.70 ± 1.56, 31.30 ± 1.18-453.85 ± 2.43 Bq kg-1 respectively. The mean value of 232Th reported higher than the world reference standard of 50 Bq kg-1. Moreover, the stations closest to the school's laboratory were noticed to be prone to more gamma radiations than the other buildings in the school. Similarly, the results of the radiological parameters estimated varied between 86.04-243.7 Bq kg-1, 40.02-115.4 nGy h-1, 0.049-0.142 mSv y-1 and 0.232-0.658 for Raeq, D(out), AEDE and Hex, respectively. Although, the results of the radiological parameters did not exceed the world safe limits, higher values of these parameters were reported at some stations closer to the school laboratory. It can be concluded that the school laboratory is prone to more gamma radiation than the class rooms and the administrative block. Therefore, the laboratory instructors and staff, who spend longer time in the laboratory, are more liable to the health risk that could result from years of exposure to gamma radiation in the laboratory.

In-situ assessment of natural terrestrial-radioactivity from Uranium-238 (238U), Thorium-232 (232Th) and Potassium-40 (40K) in coastal urban-environment and its possible health implications.

The risk of natural terrestrial radioactivity on human health is often underestimated, and environmental safety awareness is necessary. Hence, this study aims to assess natural sources of gamma radiation emitter in coastal urban-environment using the radiometric technique. The dosage of gamma radiation from a parent radionuclide such as Uranium-238 (238U), Thorium-232 (232Th) and Potassium-40 (40K) and were measured using portable gamma spectroscopy. The result showed that the measured value of 238U activity was between 10.81 [Formula: see text] 0.69 and 46.31 [Formula: see text] 1.43 Bqkg-1. The mean value was estimated to be 35.44 [Formula: see text] 0.97 Bqkg-1 which is slightly higher than the world average. Meanwhile, 232Th activity ranges from 28.42 [Formula: see text] 1.12 to 69.43 [Formula: see text] 1.76 Bqkg-1 with the calculated mean value of 92.57 [Formula: see text] 1.17 Bqkg-1 while 40K activity ranged between 31.30 ± 1.32 and 328.65 ± 2.32 Bqkg-1 with the estimated mean 137.59 [Formula: see text] 2.42 Bqkg-1. Radiological parameters such as radium equivalent (Req), internal hazard (Hint) and external hazard (Hext) assessment were in the range of 66.00 Bqkg-1 to 141.76 Bqkg-1, 0.232 to 0.452 and 0.178 to 0.383, respectively. The measured values of gamma dose-rates ranged between 54.283 ± 0.78 and 117.531 ± 1.14 nGyh-1 with the calculated mean value of 84.770 ± 0.97 nGyh-1.

Pressure effect on structures and optoelectronic attributes of mixed halide CsPb(I/Br)3: a density functional theory study.

The effect of pressure (up to 10 GPa) on the electronic and optical properties of bromine-substituted cesium lead iodide (CsPbI3), as one promising inorganic halide perovskite, is investigated using modified Backe-Johnson (mBJ) potential for the first time to our knowledge. The lattice parameters, electronic bandgap, and imaginary and real parts of the dielectric function, along with the optical absorption coefficient, are calculated. Density functional perturbation theory is employed to compute the optical properties in the photon energy range from 0.0 to 30 eV. No structural or phase-type transformation is noticed under the applied pressure, which resulted in a uniform contraction of the unit cell. Bandgap variation is seen in all the structures, with the maximum (1.65 eV) and minimum (1.46 eV) decrease found for doped and undoped CsPbBrI2, respectively. The present work provides useful information about the performance of CsPbI3-xBrx compounds under high pressure that can be utilized in designing solar cells and optoelectronics.

Zingerone Targets Status Epilepticus by Blocking Hippocampal Neurodegeneration via Regulation of Redox Imbalance, Inflammation and Apoptosis.

Epilepsy is an intricate neurological disease where the neurons are severely affected, leading to the mortality of millions worldwide. Status epilepticus (SE), induced by lithium chloride (LiCl) and pilocarpine, is the most accepted model for epilepsy. The current work aims to unravel the mechanisms underlying the anti-epileptic efficacy of zingerone (an active ingredient of ginger), which has beneficial pharmacological activities on seizure-induced behavioral, histological, neurochemical, and molecular patterns in mice. Zingerone restored cognitive function by diminishing seizure activity, escape latency, and subsequent hippocampal damage manifested in histology. Seizures are associated with local inflammation, redox imbalance, and neural loss, confirmed by the present study of SE, and was attenuated by zingerone treatment. Nuclear factor-kappa B and its downstream signaling molecules (TNF-α, IL-1ß, IL-6, NO, MPO) were activated in the LiCl-and-pilocarpine-induced group leading to inflammatory signaling, which was substantially ameliorated by zingerone treatment. The intrinsic apoptotic process was triggered subsequent to SE, as demonstrated by augmentation of cleaved caspase-3, downregulation of Bcl-2. However, zingerone treatment downregulated caspase-3 and upregulated Bcl-2, increasing cell survival and decreasing hippocampal neural death, deciphering involvement of apoptosis in SE. Therefore, zingerone plays an essential role in neuroprotection, probably by precluding oxidative stress, inflammation, and obstructing the mitochondrial pathway of apoptosis.

MEASUREMENTS OF SEASONAL VARIATIONS OF RADIOACTIVITY DISTRIBUTIONS IN RIVERINE SOIL SEDIMENT OF ADO-ODO OTA, SOUTH-WEST NIGERIA: PROBABILISTIC APPROACH USING MONTE CARLO.

The radioactivity levels were measured using a hand-held gamma-ray survey meter and NaI (Tl) based gamma spectroscopy to evaluate the seasonal variation of radioactivity levels in the riverine area of Ado-Odo Ota. The measured iso-dose map reported higher gamma dose rate of 79 nGy/h, approximately 34% higher than the world average of 59 nGy/h. The values for U-238, Th-232 and K-40 activity levels ranged between 29.9 and 21.6; 103.2 and 31.2; 802.2 and 233.5 with mean values of 26.1, 55.6 and 499.3 Bq/kg, respectively. According to the mean, 5th and 95th percentiles of the probabilities using the Monte Carlo simulation, the Radium equivalent activities and the absorbed dose rates are within their respective recommended limits of 370 Bq/kg and 84 nGy/h. This study could be used to monitor dose rates and radiological risks for the areas covering the small area (Ado-Odo Ota) to the larger area (West African Region) as baseline data.

Piperine Regulates Nrf-2/Keap-1 Signalling and Exhibits Anticancer Effect in Experimental Colon Carcinogenesis in Wistar Rats.

Colon cancer is the most common cancer in men and women globally, killing millions of people annually. Though there widespread development has been made in the management of colorectal cancer, still there is an urgent need to find novel targets for its effective treatment. Piperine is an alkaloid found in black pepper having anticancer, anti-inflammatory activities, safe and nutritive for human consumption. Nuclear factor-erythroid 2-kelch-like ECH-associated protein 1(Nrf-2/Keap-1)/Heme-oxygenase1 (HO-1) signaling pathway plays a vital part in shielding cells from intracellular oxidative stress and inflammation. A potential cross-talk between the Nrf-2 and NF-κB pathways is recognized during cancerous growth and expansion. We studied this pathway extensively in the present study to discover novel targets in the prevention of chemically induced colon cancer with piperine to simulate human colon cancer pathology. Animals were divided into four groups. Groups1 and 2 were used as a negative control and positive control where 1,2-Dimethylhydrazine, DMH was administered in group 2, while group 3 and 4 were prevention groups where piperine at two different doses was given two weeks prior to DMH and continued until end of experiment. We found that piperine inhibited NF-κB by the activation of Nrf-2, blocking downstream inflammatory mediators/cytokines (TNF-α, IL-6, IL-1ß, Cox-2, PGE-2, iNOS, NO, MPO), triggering an antioxidant response machinery (HO-1, NQO-1, GSH, GR, GPx, CAT, SOD), scavenging ROS, and decreasing lipid peroxidation. Histological findings further validated our molecular findings. It also downregulates CEA, MDF and ACF, markers of precancerous lesions in colon, alleviates infiltration of mast cells and depletes the mucous layer. Our results indicate that piperine may be an effective molecule for the prophylactic treatment of colon carcinogenesis by targeting the NF-κB/Nrf-2/Keap-1/HO-1 pathway as a progressive strategy in the preclusion and effective treatment of colorectal cancer.

Elliptical metallic rings-shaped fractal metamaterial absorber in the visible regime.

Achieving the broadband response of metamaterial absorbers has been quite challenging due to the inherent bandwidth limitations. Herein, the investigation was made of a unique kind of visible light metamaterial absorber comprising elliptical rings-shaped fractal metasurface using tungsten metal. It was found that the proposed absorber exhibits average absorption of over 90% in the visible wavelength span of 400-750 nm. The features of perfect absorption could be observed because of the localized surface plasmon resonance that causes impedance matching. Moreover, in the context of optoelectronic applications, the absorber yields absorbance up to ~ 70% even with the incidence obliquity in the range of 0°-60° for transverse electric polarization. The theory of multiple reflections was employed to further verify the performance of the absorber. The obtained theoretical results were found to be in close agreement with the simulation results. In order to optimize the results, the performance was analyzed in terms of the figure of merit and operating bandwidth. Significant amount of absorption in the entire visible span, wide-angle stability, and utilization of low-cost metal make the proposed absorber suitable in varieties of photonics applications, in particular photovoltaics, thermal emitters and sensors.

Density functional theory study of mixed halide influence on structures and optoelectronic attributes of CsPb(I/Br)3.

This paper reports on the influence of the bromine (Br) atoms substitution on the structures and optoelectronic traits of ${\text{CsPbI}_3}$CsPbI3, wherein the density functional theory (DFT) simulation was performed, using all electrons full potential linearized augmented plane-wave method. Furthermore, the generalized gradient approximation, local density approximation, and modified Becke-Johnson exchange-correlation potential were used to improve the optimization and band structure calculations. The calculated lattice constants of ${\text{CsPbI}_3}$CsPbI3 and ${\text{CsPbBr}_3}$CsPbBr3 were consistent with the experimental values. All the studied compounds revealed wide and direct bandgap energies at the R-symmetry point, which varied from 1.74-2.23 eV. The obtained refractive indices of the ${\text{CsPbI}_3}$CsPbI3, ${\text{CsPbBrI}_2}$CsPbBrI2, ${\text{CsPbIBr}_2}$CsPbIBr2, and ${\text{CsPbBr}_3}$CsPbBr3 compounds were correspondingly 2.265, 2.245, 2.090, and 2.086. Present findings may contribute towards the development of experimental studies on the proposed compounds with controlled properties useful for the solar cells.

CO2 capture through electro-conductive adsorbent using physical adsorption system for sustainable development.

The most critical energy and environmental challenge that our planet is facing today is to minimize the dependence on fossil fuels. Carbon dioxide may be of utmost significance as a solution of this issue through realization of carbon neutral energy cycle. Potentially, this could be achieved through the carbon dioxide capture as the urgent response to ongoing climate change. Activated carbon (AC) adsorption is one the most effective, environment friendly and techno-economic process for the carbon capture. In the current research, an electro-conductive-activated carbon was prepared by mixing powdered activated carbon (PAC) with an electro-conductive polymer (ECP). Different ratios of 0, 25, 50, 75 and 100 wt% of ECP with PAC were used for the different analyses of activated carbons in a gas mixture of CO2/N2 using a physical adsorption system. Adsorption and desorption analyses, capacities of the process and desorption effects were examined. Electro-conductive polymers (ECP) were mixed with AC samples, where breakthrough time was increased up to 400% when mixed with the PAC for CO2 adsorption. Following adsorption analysis, desorption of activated carbons was conducted with different potentials. It was revealed that mixing could help the PAC sample to overcome the packing issue to increase the breakthrough capacity and the volumes before and after the breakthrough adsorption in the packed bed systems. The desorption rates of the PAC sample were also enhanced, and fast desorption was observed when mixed with ECP. It is envisioned that this method is very much promising carbon capture method for the techno-economic feasibility and sustainable development of the environment.

Investigation of natural environmental radioactivity concentration in soil of coastaline area of Ado-Odo/Ota Nigeria and its radiological implications.

Natural radioactivity in coastaline area soil of Ado-Odo/Ota has been carried out to ascertain the presence of radionuclides using gamma-ray spectroscopy (HPGe detector). The result showed that U-238, Th-232 and K-40 ranged from 24 ± 7-49 ± 10; 67 ± 6-120 ± 9 and 88 ± 17-139 ± 20 Bqkg-1 respectively. The radium equivalent for the samples ranged from 132.51 to 230.91 Bqkg-1 with mean value of 185.89 Bqkg-1. The mean value for the gamma dose rate for the soil samples was estimated to be 81.32 nGyh-1. The estimated values of annual effective dose equivalent ranged from 0.61 to 1.07 mSv y-1. The estimation of alpha index representative (Iα) ranged from 0.12 to 0.24 with mean value of 0.21 while the gamma representative index ranged between 0.465 and 0.810. The activity utilization index of the soil samples ranged from 1.09 to 1.89 with mean value of 1.53. The radiological implication in the study area has shown that the soil samples with gamma dose rate value of 89.99 nGyh-1, 94.39 nGyh-1, 97.40 nGyh-1 and 101.04 nGyh-1 respectively are higher than the recommended value of 80 nGyh-1 and may pose health implication for long term exposure.

Comparative Analysis of Natural Radioactivity Content in Tiles made in Nigeria and Imported Tiles from China.

In this investigation, natural radioactive contents in tiles manufactured in Nigeria and tiles imported from China were measured using gamma ray spectroscopy. High Purity Germanium detector was used to estimate the concentrations of some radioisotopes present in 17 samples of various tiles from Nigeria and China. The average activity concentrations of 226Ra, 232Th, and 40K for the tiles were found to be 68.2 ± 0.5; 173.9 ± 9.2 and 490 ± 15 Bq/kg and 58.2 ± 0.5, 161.5 ± 9.4 and 455.7 ± 15.1 Bq/kg for the tiles from Nigeria and China respectively. Radiological hazard indices such as absorbed dose rate, radium equivalent activity, external Hazard Index (Hex), internal Hazard Index (Hin), Annual Effective Dose (mSv/y), Gamma activity Index (Iγ) and Alpha Index (Iα) were determined for both kind of tiles from Nigeria and China. The mean values obtained were: 354.56 and 317.16 Bq/kg; 169.22 nGyh-1 and 153.92 nGyh-1; 0.95 and 0.87; 1.14 and 1.08; 1.59 mSv/y and 1.52 mSv/y; 1 and 1.15 and; 0.34 and 0.29 respectively. The mean value of radium equivalent obtained in this study is less than that of the international reference value of 370 Bq/kg for the both kind of tiles.

In-situ regeneration of activated carbon with electric potential swing desorption (EPSD) for the H2S removal from biogas.

In-situ regeneration of a granular activated carbon was conducted for the first time using electric potential swing desorption (EPSD) with potentials up to 30 V. The EPSD system was compared against a standard non-potential system using a fixed-bed reactor with a bed of 10 g of activated carbon treating a gas mixture with 10,000 ppm H2S. Breakthrough times, adsorption desorption volume, capacities, effect of regeneration and desorption kinetics were investigated. The analysis showed that desorption of H2S using the new EPSD system was 3 times quicker compared with the no potential system. Hence, physical adsorption using EPSD over activated carbon is efficient, safe and environmental friendly and could be used for the in-situ regeneration of granular activated carbon without using a PSA and/or TSA system. Additionally, adsorption and desorption cycles can be obtained with a classical two column system, which could lead towards a more efficient and economic biogas to biomethane process.

Effects of compensating the temperature coefficient of frequency with the acoustic reflector layers on the overall performance of solidly mounted resonators.

Thin film acoustic wave resonator based devices require compensation of temperature coefficient of frequency (TCF) in many applications. This work presents the design and fabrication of temperature compensated solidly mounted resonators (SMRs). The characteristics of each material of the layered structure have an effect on the device TCF but depending on the relative position with respect to the piezoelectric material in the stack. The influence of material properties of the different layers composing the device on the TCF is discussed in detail. TCF behavior simulation is done with Mason's model and, to take into account the deterioration of overall performance due to the finite lateral size and shape of the resonator, we have used 2D and 3D finite element modelling of the resonators. The overall behavior of the device for external loads is predicted. SMRs are designed according to simulations and fabricated with different configurations to obtain TCF as near to zero as possible with an optimized response. Resonators are made by depositing Mo/AlN/Mo piezoelectric stacks on acoustic reflectors. As reflector materials, conductive W and insulating WOx films have been used as high acoustic impedance materials. SiO2 films are used as low acoustic impedance material.

Effect of co-doping of sodium on the thermoluminescence dosimetry properties of copper-doped zinc lithium borate glass system.

The effect of sodium as a co-dopant on the thermoluminescence (TL) properties of copper-doped zinc lithium borate (ZLB: Cu) subjected to Co-60 gamma radiation is reported in this study. TL intensity is enhanced with the introduction of sodium in ZLB: Cu. The obtained glow curve is simple with a single peak. The annealing procedure and the best heating rate for the proposed thermoluminescent dosimeter (TLD) are established, and the phosphor is reusable. The TL response within the dose range of 0.5-1000Gy is investigated. The results show that the thermal fading behaviour is improved significantly.

Synthesis and Photoluminescence of Single-Crystalline Fe(III)-Doped CdS Nanobelts.

In this paper, we report the synthesis and optical properties of Fe(III) doped CdS nanobelts (NBs) via simple Chemical Vapor Deposition (CVD) technique to explore their potential in nano-optics. The energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) analysis manifested the presence of Fe(III) ions in the NBs subsequently confirmed by the peak shifting to lower phonon energies as recorded by Raman spectra and shorter lifetime in ns. Photoluminescence (PL) spectrum investigations of the single Fe(III)-doped CdS NBs depicted an additional PL peak centered at 573 nm (orange emission) in addition to the bandedge(BE) emission. The redshift and decrease in the BE intensity of the PL peaks, as compared to the bulk CdS, confirmed the quenching of spectra upon Fe doping. The synthesis and orange emission for Fe-doped CdS NBs have been observed for the first time and point out their potential in nanoscale devices.

Magnetic Properties of Polyvinyl Alcohol and Doxorubicine Loaded Iron Oxide Nanoparticles for Anticancer Drug Delivery Applications.

The current study emphasizes the synthesis of iron oxide nanoparticles (IONPs) and impact of hydrophilic polymer polyvinyl alcohol (PVA) coating concentration as well as anticancer drug doxorubicin (DOX) loading on saturation magnetization for target drug delivery applications. Iron oxide nanoparticles particles were synthesized by a reformed version of the co-precipitation method. The coating of polyvinyl alcohol along with doxorubicin loading was carried out by the physical immobilization method. X-ray diffraction confirmed the magnetite (Fe3O4) structure of particles that remained unchanged before and after polyvinyl alcohol coating and drug loading. Microstructure and morphological analysis was carried out by transmission electron microscopy revealing the formation of nanoparticles with an average size of 10 nm with slight variation after coating and drug loading. Transmission electron microscopy, energy dispersive, and Fourier transform infrared spectra further confirmed the conjugation of polymer and doxorubicin with iron oxide nanoparticles. The room temperature superparamagnetic behavior of polymer-coated and drug-loaded magnetite nanoparticles were studied by vibrating sample magnetometer. The variation in saturation magnetization after coating evaluated that a sufficient amount of polyvinyl alcohol would be 3 wt. % regarding the externally controlled movement of IONPs in blood under the influence of applied magnetic field for in-vivo target drug delivery.

Uptake and clearance analysis of Technetium99m labelled iron oxide nanoparticles in a rabbit brain.

Nanoparticles as solid colloidal particles are extensively studied and used as anticancer drug delivery agents because of their physical properties. This current research aims to prepare water base suspension of uncoated iron oxide nanoparticles and their biodistribution study to different organs, especially the brain, by using a single photon emission computed tomography gamma camera. The water-based suspension of iron oxide nanoparticles was synthesised by a reformed version of the co-precipitation method and labelled with Tc99m for intravenous injection. The nanoparticles were injected without surface modification. X-ray diffraction (XRD), energy dispersive spectrometry (EDS) and transmission electron microscope (TEM) techniques were used for characterisation. Peaks of XRD and EDS indicate that the particles are magnetite and exist in aqueous suspension. The average diameter of iron oxide nanoparticles without any surface coating determined by TEM is 10 nm. These particles are capable of evading the reticuloendothelial system and can cross the blood-brain barrier in the rabbit. The labelling efficiency of iron oxide nanoparticles labelled with Tc99m is 85%, which is good for the biodistribution study. The sufficient amount of iron oxide nanoparticles concentration in the brain as compared with the surrounding soft tissues and their long blood retention time indicates that the water-based suspension of iron oxide nanoparticles may be an option for drug delivery into the brain.

Rational use of medicines in older adults: Can we do better during clinical development?

There is an evidence gap to ensuring safe/effective use of medicines in older adults. Generating clinical data in these patients poses ethical and operational challenges, yielding results that may not be generalizable to the overall population. Modeling and simulation (M&S) is proposed as a basis for assessing the impact of age-related changes and their clinical implications. M&S can be used in conjunction with bridging and extrapolation to ensure the selection of appropriate dose(s)/regimen(s) in this population.

Protease-activated receptor 1 suppresses Helicobacter pylori gastritis via the inhibition of macrophage cytokine secretion and interferon regulatory factor 5.

Chronic gastritis from Helicobacter pylori infection is a major factor in the development of gastric adenocarcinoma. Factors that regulate gastritis severity are important in determining which individuals are susceptible to H. pylori-associated disease. Although protease-activated receptor 1 (PAR1) has been identified as one such host factor, its mechanism of action is unknown. Using chimeric mice, we demonstrated that PAR1-mediated protection against H. pylori gastritis requires bone marrow-derived cells. Analyses of the gastric mucosa revealed that PAR1 suppresses cellular infiltration and both T helper type 1 (Th1) and T helper type 17 (Th17) responses to infection. Moreover, PAR1 expression was associated with reduced vaccine-mediated protection against H. pylori. Analyses of H. pylori-stimulated macrophages revealed that PAR1 activation suppressed secretion of interleukin (IL)-12 and IL-23, key drivers of Th1 and Th17 immunity, respectively. Furthermore, PAR1 suppressed interferon regulatory factor 5 (IRF5), an important transcription factor for IL-12 and IL-23, both in the infected mucosa and following bacterial stimulation. PAR1 suppression of IRF5 and IL-12/23 secretion by macrophages provides a novel mechanism by which the host suppresses the mucosal Th1 and Th17 response to H. pylori infection. Dysregulation of this process is likely an important factor in the susceptibility of some individuals to H. pylori-associated disease.