pH Monitoring Research Articles

24 h combined esophageal multichannel intraluminal impedance and pH monitoring in children with chronic cough

BackgroundChronic cough in children is closely related to gastroesophageal reflux (GER). However, this association has not been adequately studied due to a lack of diagnostic tools. Combined esophageal multichannel intraluminal impedance and pH (MII-pH) monitoring is considered the most accurate method for evaluating the association between symptoms and reflux, but data on its use in children with chronic cough are still lacking. We aimed to assess the association between chronic cough and GER in children through MII-pH monitoring.MethodsChildren with chronic cough (> 4 weeks) who were suspected gastroesophageal reflux disease(GERD) were selected to undergo 24 h MII-pH monitoring at our hospital. Patients were divided into groups according to their age, body position, reflux index (RI) or total reflux events, and the differences between the groups were analyzed. Then the significance and value of 24 h pH and impedance monitoring in chronic cough and the relationship between chronic cough and reflux were discussed.ResultsOverall, 426 patients were included. The median age was 12 months (interquartile range: 6–39.5 months), 129 (30.3%) patients had RI > 7% detected by pH-metry, and 290 (68.1%) patients had positive diagnosis based on the impedance data. GER predominantly occurred in the upright position and mostly involved weakly acidic reflux and mixed gas–liquid reflux. There were 14.1% of children in non-acid GER group were SAP positive showing no difference in acid GER group 13.2% (P = 0.88), whereas patients with SAP > 95% in MII positive group (47[16.2%]) is higher than in MII negative group (P < 0.05).ConclusionTwenty four hour MII-pH monitoring is safe, well tolerated in children, but also has a higher detection rate of gastroesophageal reflux. It can find identify weakly acidic reflux, weakly alkaline reflux and reflux events with different physical properties, which can explain the relationship between GER and chronic cough more comprehensively. It provides new approach for exploring the etiology, diagnosis and treatment of children with chronic cough.

Biomimetic FeNi-MOF assisted intelligent theranostic hydrogels for pH identification and treatment of wounds

Wound healing poses a significant challenge because of prolonged treatment and compromised tissue regeneration caused by bacterial infections. Timely and efficient wound monitoring strategies are urgently needed to assess wound progression and healing in real time. To address this, we present an intelligent theranostic hydrogel system based on dual-site biomimetic FeNi metal–organic frameworks (MOFs) that enables intelligent wound pH monitoring and effective prevention of infection. Notably, the quasi-MOFs among the pristine bimetallic FeNi-MOFs and their derivatives demonstrate remarkable performance in mimicking superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, along with exceptional stability. The synthesized MOF hydrogels act as wound dressings for monitoring wound status and promoting healing. By incorporating the quasi-MOF and a pH indicator (phenol red) into the hydrogel, the hybrid system allows accurate pH detection, reflecting dynamic wound conditions. Furthermore, visual changes captured by smartphones provide real-time signals for remote assessment of wound pH, facilitating precise antimicrobial therapy and on-demand pH monitoring. This multifunctional theranostic hydrogel represents a significant advancement in the development and optimization of MOF hydrogels, offering a platform for efficient wound healing and comprehensive wound assessment.

Biocompatible Re-Containing Block Copolymers for Intracellular pH Mapping in the PLIM Mode.

Monitoring of intracellular pH is of great importance since deviation of this parameter from the "normal" magnitudes can be considered as an indicator of various pathologies. Thus, the development of new efficient and biocompatible sensors suitable for application in biological systems and capable of quantitative pH estimation remains an urgent chemical task. Herein, we report the synthesis of a series of phosphorescent rhenium [Re(NN)(CO)2(PR3)2]+ complexes based on the NN diimine ligands containing pH-responsive carboxylic groups and styrene-containing phosphine ligands. The complexes, which display the highest pH sensitivity, were copolymerized with polyvinylpyrrolidone using the RAFT protocol to impart water solubility and to protect the chromophores from interaction with molecular oxygen. The resulting copolymers show an emission lifetime response onto pH variations in the physiological range. Cellular experiments with Chinese hamster ovary cells (CHO-K1) reveal easy internalization of the probes in cell culture and an approximately uniform distribution in cells, with some preference for location in acidic compartments (late endosomes and lysosomes). Using nigericin to homogenize intra- and extracellular pH, we built a calibration of lifetime versus pH in live CHO-K1 cells. Analysis of the phosphorescence lifetime imaging microscopy (PLIM) data confirms the applicability of the obtained sensors for monitoring the intracellular pH in cell cultures.

Treating acid reflux without compressing the food passageway: 4-year safety and clinical outcomes with the RefluxStop device in a prospective multicenter study

IntroductionRefluxStop is an implantable device for laparoscopic surgical treatment of gastroesophageal reflux disease (GERD) to restore and maintain lower esophageal sphincter and angle of His anatomy without encircling and putting pressure on the food passageway, thereby avoiding side effects such as dysphagia and bloating seen with traditional fundoplication. This study reports the clinical outcomes with RefluxStop at 4 years following implantation of the device.MethodsA prospective, single arm, multicenter clinical investigation analyzing safety and effectiveness of the RefluxStop device in 50 patients with chronic GERD.ResultsAvailable data are presented for 44 patients at 4 years with the addition of three patients at 3 years carried forward. At 4 years, median GERD-HRQL score was 90% reduced compared to baseline. Two patients (2/44) used regular daily proton pump inhibitors (PPIs) despite subsequent 24-h pH monitoring off PPI therapy yielding normal results. There were no device-related adverse events (AEs), esophageal dilations, migrations, or explants during the entire study period. AEs reported between 1 and 4 years were as follows: one subject with heartburn and a pathologic pH result with device positioned too low at surgery; one subject with dysphagia, thus, 46/47 patients reported no dysphagia-related AEs between years 1 and 4. Two patients (2/47) were dissatisfied with treatment despite normal 24-h pH monitoring, of whom one had manometry-verified dysmotility at 6 months, indicating dissatisfaction for reasons other than acid reflux.ConclusionThese results confirm the excellent and already published 1-year results as stable in the long-term, supporting the safety and effectiveness of the RefluxStop device in treating GERD for over 4 years. GERD-HRQL score, pH testing, and PPI usage indicate treatment success without dysphagia or gas-bloating and only minimal incidence of other AEs. This favorably low rate of AEs is likely attributable to RefluxStop’s dynamic physiologic interaction and non-encircling nature.

Reliability and validity of the German version of the Glasgow Edinburgh Throat Scale

Many patients who consult the ENT doctor suffer from globus sensation, as a term for a multifactorial symptom description. It is particularly important during initial consultation to take the often-sensitive patients seriously and to offer a structured diagnostic clarification. Today, there is a lack of a screening tool in everyday clinical practice that can be used to differentiate the globus sensations more closely and assess their severity OBJECTIVES: The reliability and validity of the German version of the Glasgow Edinburgh Throat Scale (GETS) were examined. The original GETS questionnaire was translated into German (GETS-G) and completed by 60 patients with globus sensation (>3 months) in a prospective observational study. All patients received a clinical examination a sonography of the neck. In patients without an identifiable organic cause, a pH monitoring was carried out. A local organic cause for the globus sensation was found in 30 patients (50%). In addition, reflux was detected in 24 patients (40%) using pH monitoring. No cause could be determined in only 6 patients (10%). According to the overall score (Q1-Q12), there was no significant difference between these three groups. The Cronbach's alpha for assessing reliability was 0.88 in the 12-item analysis. Principal component analysis yielded a globus scale, dysphagia scale and a chronic pharyngeal irritation scale. The GETS-G showed high reliability and validity, which justifies its use in patients with globus sensation in German-speaking countries and may lead to a better assessment of the severity of this symptom.

The impact of gastroesophageal reflux disease on upper esophageal sphincter function: Insights from PH impedance and high-resolution manometry.

Lower esophageal sphincter (LES) pathophysiology has been established in gastroesophageal reflux disease (GERD); however, less is understood regarding the role the upper esophageal sphincter (UES) plays in preventing laryngopharynphageal reflux. Sustained UES basal pressure prevents reflux into the pharynx while allowing relaxation during ingestion. We investigate whether GERD influences UES function via HRM and pH Impedance testing. A retrospective analysis of 318 patients who underwent high-resolution manometry with trans-nasally placed manometric catheter and 24-h multichannel intraluminal impedance pH monitoring. One hundred and forty-seven patients met Lyon consensus criteria for GERD based on acid exposure time >6%. The most common chief concern was heartburn or reflux, present in 59% of these patients. Upper esophageal sphincter basal and residual pressures were not significantly different between patients with GERD when compared to those without GERD, including a subanalysis of patients with extraesophageal symptoms. The LES basal and residual pressures, DCI and MNBI are statistically lower in patients with pathologic GERD. HRM and pH Impedance testing demonstrates no difference in UES basal and residual pressures based on pH diagnosis of GERD. We redemonstrate the association with hypotonic LES, diminished DCI and MNBI with GERD.

Resourceful exploitation of sedimentary clay: Designing a dual-chambered borosilicate glass reactor system for the efficient treatment of malachite green and phenol through SCRT adsorption and 5%Fe@SRCT catalysis via CWPO, with evaluation of seed germination and fish survival.

This study presents an innovative double-walled borosilicate glass reactor system for the efficient treatment of liquid and gaseous wastewater. This reactor system allows precise temperature control, continuous pH monitoring, and controlled dosing of reagents to optimize reaction conditions. Detailed characterization was carried out by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), BET (specific surface area) analysis, point of zero charge (PZC), and scanning electron microscopy (SEM) for the SCR, SCRT, and 5%Fe@SCRT materials. For Malachite Green adsorption, SRCT demonstrated a maximum adsorption capacity of 39.78 ±0.5mg/g using the Langmuir isotherm model and followed pseudo-second-order kinetics. Optimum conditions for adsorption were found to be: an initial concentration of 50 ppm, an adsorbent dosage of 1g/l, a pH of 8.5, and a temperature of 50°C. For the catalytic oxidation of phenol, 5%Fe@SRCT achieved a remarkable removal rate of 99.9±0.1% under optimum conditions (50 ppm phenol, 1g/l catalyst dosage, pH3.5, H2O2 concentration 8.7mM, and temperature 70°C). Intermediates identified during the reaction included hydroquinone, benzoquinone, catechol, and resorcinol, with degradation occurring over a 60-minute reaction period. The 5%Fe@SCRT material showed excellent reusability in the removal of phenol by catalytic oxidation, with no significant loss of efficiency over three cycles, while the SRCT underwent three cycles of regeneration for the adsorption of Malachite Green. Scavenger tests confirmed the involvement of hydroxyl radicals in the catalytic oxidation process. In addition, fish survival tests after catalytic oxidation of phenol by 5%Fe@SRCT showed no impact on fish, underlining the environmental safety of this process. In addition, germination tests after decolorization of MG by SRCT demonstrated a good effect with no negative impact, reinforcing the ecological value of this innovative technology. These results highlight the innovative use of SCRT and 5%Fe@SCRT as versatile materials for environmental remediation, exploiting their effective adsorption capacities and efficient catalytic oxidation performance within the proposed double-walled borosilicate glass reactor system. PRACTITIONER POINTS: The study demonstrates the effectiveness of an innovative reactor system employing SRCT adsorbent and Fe@SRCT catalyst for efficient removal of malachite green and phenol from wastewater. Environmental impact assessment, including seed germination and fish survival evaluation, validates the method's eco-friendly potential. Implementation of this approach could significantly contribute to sustainable water treatment practices.

Piloting an intraoral pH device to track gastroesophageal reflux in adults

This study evaluated in vivo, an intraoral device against the gold standard esophageal device for gastroesophageal reflux disease (GERD) monitoring. Subjects scheduled for a catheter-based esophageal pH/impedance testing at a gastroenterology clinic were recruited. They were screened using the GerdQ questionnaire, demographics and dental conditions recorded. A prototype intraoral device, consisting of a Bravo™ capsule embedded in an Essix-style retainer fabricated for each subject, monitored intraoral pH. Concurrently, subjects underwent 24-h esophageal pH-impedance monitoring. A self-administered survey elicited the comfort and acceptance of both devices. The study recruited ten adult subjects (23 to 60-years-old) with a median GerdQ score of 9.5 corresponding to a 79% likelihood of GERD. Subjects with severe dental erosion had significantly (p < 0.05) higher acid exposure time and more non-meal reflux events. No adverse events were associated with the intraoral device while one was recorded for the esophageal device. The intraoral device was significantly more comfortable to place, more comfortable to wear, and interfered less with daily routine compared to the esophageal device. Accuracy of the intraoral device ranged between 86.15% and 37.82%. Being more tolerable than traditional esophageal pH monitoring, intraoral pH monitoring may be a useful adjunct for the diagnosis and management of GERD.

Association between Oral Microbiome and Gastroesophageal Reflux Severity.

Background/Objectives: Gastroesophageal reflux disease (GORD) is caused by gastric contents refluxing back into the oesophagus and oral cavity. It can lead to injuries to the mucosa in the form of erosion and ulcers. Our past research have shown acid reflux severity and disease progression is associated with alternations in the microbiota of the distal oesophagus. The aim of this study was to explore whether changes in the oral microbiota occurred in GORD patients and establish any associations with reflux severity. Methods: Fresh mouthwash samples were collected from 58 patients experiencing reflux symptoms referred for 24 h pH monitoring. The participants were categorised into three groups based on their DeMeester scores: Normal (<14.72), Mild (14.2-50), and Moderate/severe (>51). Microorganism identity and diversity were generated using hypervariable tag sequencing and analysing the V1-V3 region of the 16S rRNA gene. Results: No differences in microbiota diversity were found in oral microbiota between groups using the Chiao1 diversity index and Shannon diversity index. Microbiota in the Mild group showed reductions in Rothia dentocariosa and Lautropia, while Moryella and Clostridiales_1 were increased compared with the Normal group. In the Moderate/severe group, the abundance of Rothia aeria was reduced compared with the Normal group, while Schwartzia, Rs_045, Paludibacter, S. satelles, Treponema, and T. socranskii all had increased abundance. The abundance of Prevotella pallens was higher in the Mild group compared with Moderate/severe, while S. satelles and Paludibacter abundances were lower. Conclusions: Our study shows the oral microbiome show significant differences between acid reflux severity groups, as categorised by DeMeester score.

Redox homeostasis and pH monitoring: a step forward to personalized medicine and dermatology

Skin is continually subjected to various environmental stressors, such as pollution, UV rays, and other oxidative damage factors. It is obligatory to ascertain the exact importance of redox status and ROS indicators, which may be assessed in diverse physiological fluids and tissues. Reactive oxygen species (ROS) can cause lipid peroxidation, which can compromise the integrity and functionality of skin cells by degrading membrane lipids. This may compromise the skin barrier, making the skin more prone to infections and environmental irritants, increasing water loss and dryness. Collagen in the dermis can covalently link to malondialdehyde (MDA), a byproduct of lipid peroxidation generated by oxidatively damaged skin lipids, to form MDA-collagen adducts. Several types of skin cancer are associated with a heightened vulnerability of DNA purine and pyrimidine bases to oxidative damage and altered DNA repair capacity (DRC). Damage from ROS may cause hyaluronate to become less viscous, which increases its susceptibility to degradation. Elastin hydrodynamic radius decreased the rate of self-assembly in response to ROS. Alterations in redox homeostasis can lead to various diseases and conditions, including vitiligo, actinic keratosis, psoriasis, contact dermatitis, systemic sclerosis, the onset of wrinkles, and skin aging. The most recent formulations' capacity to improve pH and Redox simultaneously can be attained by carefully selecting proposed antioxidant formulations. The combination of modern preparations is currently available and should be used in accordance with the suggested guidelines.

Skin-attachable Tb-MOF ratio fluorescent sensor for real-time detection of human sweat pH

The pH of human sweat is highly related with a variety of diseases, whereas the monitoring of sweat pH still remains challenging for ordinary families. In this study, we developed a novel dual-emission Tb-MOF using DPA as the ligand and further designed and constructed a skin-attachable Tb-MOF ratio fluorescent sensor for real-time detection of human sweat pH. With the increased concentration of H+, the interaction of H+ with carbonyl organic ligand leads to the collapse of the Tb-MOF crystal structure, resulting in the interruption of antenna effect, and correspondingly increasing the emission of the ligand at 380 nm and decreasing the emission of the central ion Tb3+ at 544 nm. This Tb-MOF nanoprobe has a good linear response in the pH range of 4.12–7.05 (R2 = 0.9914) with excellent anti-interference ability. Based on the merits of fast pH response and high sensitivity, the nanoprobe was further used to prepare flexible wearable sensor. The wearable sensor can detect pH in the linear range of 3.50–6.70, which covers the pH range of normal human sweat (4.50–6.50). Subsequently, the storage stability and detection accuracy of the sensors were evaluated. Finally, the sensor has been successfully applied for the detection of pH in actual sweat samples from 21 volunteer and the real-time monitoring of pH variation during movement processing. This skin-attachable Tb-MOF sensor, with the advantages of low cost, visible color change and long shelf-life, is appealing for sweat pH monitoring especially for ordinary families.

A Chromium-Based magnetic resonance probe for in situ gastric pH imaging

Effective monitoring of gastric fluid pH is crucial for diagnosing gastric diseases and evaluating anti-gastric-acid therapies. The invasiveness and low patient compliance with traditional gastric fluid aspiration methods highlight the need of a non-invasive, real-time technique for in situ gastric pH monitoring. This study introduces a novel chromium (Cr)-based magnetic resonance probe, Cr(OH)3@HSA, specifically designed for pH-sensitive gastric imaging. Synthesized via an albumin-mediated biomimetic mineralization process, Cr(OH)3@HSA possesses an amorphous structure that facilitates the sensitive release of paramagnetic Cr(III) ions in acidic environments. This release substantially decreases the longitudinal relaxation time of surrounding hydrogen protons, as demonstrated by an 18.29-fold increase in the longitudinal relaxation rate from pH 6.5 to pH 1.0. In vivo experiments show that Cr(OH)3@HSA accurately detects abnormal gastric pH levels and evaluates the efficacy of gastric antiacids, surpassing the performance of the conventional “always-on” contrast agent, Magnevist®. Notably, our research reveals that chromium picolinate, a common dietary supplement for diabetes, generates a “turn-on” signal in the gastrointestinal tract, suggesting potential MR signal interference in diabetic patients. Consequently, we recommend that diabetic patients avoid chromium-based dietary supplements prior to MRI procedures to prevent Cr(III)-induced signal alterations.

Flexible Multimodal Sensors Enhanced by Electrospun Lead-Free Perovskite and PVDF-HFP Composite Form-Stable Mesh Membranes for In Situ Plant Monitoring.

The pH and humidity of the crop environment are essential indicators for monitoring crop growth status. This study reports a lead-free perovskite/polyvinylidene fluoride-hexafluoropropylene composite (LPPC) to enhance the stability and reliability of in situ plant pH and humidity monitoring. The mesh composite membrane of LPPC illustrates a hydrophobic contact angle of 101.982°, a tensile strain of 800%, and an opposing surface potential of less than -184.9 mV, which ensures fast response, high sensitivity, and stability of the sensor during long-term plant monitoring. The LPPC-coated pH electrode possesses a sensitivity of -63.90 mV/pH, which provides a fast response within 5 s and is inert to environmental temperature interference. The LPPC-coated humidity sensor obtains a sensitivity of -145.7 Ω/% RH, responds in 28 s, and works well under varying light conditions. The flexible multimodal sensor coated with an LPPC membrane completed real-time in situ monitoring of soilless strawberries for 17 consecutive days. Satisfactory consistency and accuracy performance are observed. The study provides a simple solution for developing reliable, flexible wearable multiparameter sensors for in situ monitoring of multiple parameters of crop environments.

Remote Water Quality Monitoring System In Shrimp Ponds With Photovoltaic (PV)-Based Energy Source

Introduction: Shrimp has great potential to be used as a business field in Indonesia. Especially in Parigi Regency itself, there are now many shrimp ponds that can be found because of the benefits obtained, so people are interested in making shrimp farming a livelihood. One of the main problems of shrimp ponds is pond water quality. There are several factors that affect pond water quality, namely water temperature, water pH, and water salinity, good pond water quality management can maintain quality standards and can increase shrimp yield and productivity Method: To facilitate the shrimp farmers, innovations need to be made in order to help the shrimp farmers manage their shrimp ponds, therefore using a remote water quality monitoring was system in shrimp ponds with photovoltaic (PV) based energy sources is expected to be an innovation in managing shrimp ponds, especially in monitoring water quality in shrimp ponds. The monitoring system designed using the NRF24L01 module as a remote communication module, at the research location the distance from the shrimp pond to the house is approximately 100 meters, so the tools that have been designed can facilitate shrimp farmers to monitor the shrimp pond Results and Disscussion: The results of testing the DS18B20 temperature sensor compared with a digital thermometer measuring instrument get an average error of 0.014%. The test results of the pH sensor compared to the pH meter get an average error of 0.026%. TDS sensor test results compared with the TDS meter get an average error of 0.04%. Conclusion: The temperature, pH, and salinity monitoring system uses transmitter and receiver modules, where the transmitter module reads and sends data to the receiver module wirelessly with NRF24L01. Using DS18B20 temperature, pH, and TDS sensors, as well as energy from photovoltaics, this system helps shrimp farmers monitor pond water quality remotely.

Dual-modal fiber-optic sensor for simultaneous pH and temperature monitoring in tumor microenvironment

The tumor microenvironment (TME) is a complex system. Temperature, pH, oxygen content, and other biomarkers comprehensively reflect the growth state of the tumor, necessitating a multi-parameter detection strategy to garner the precise status of tumor for treatment guidance. Fluorescence imaging technology is a promising tool for realizing this goal due to its advantages of low cost, real-time responses, and high sensitivity. However, several limitations, including the shallow penetration depth of fluorescence signals in biological tissues and the potential crosstalk between multiple fluorescence signals, hinder the practical application of current fluorescence imaging technology. In this paper, a dual-mode optical fiber sensor consisting of a fiber fluorescence pH sensor and a fiber Bragg grating (FBG) temperature sensor is presented. The compact sensor uses different principles for pH and temperature monitoring, thus effectively eliminating potential crosstalk between different signals. In addition, its small size allows it to be inserted into deep tissues for detection. The sensor responds quickly to changes in pH.Moreover, the temperature sensitivity of FBG packaged with PDMS is 34 % higher than the uncoated FBG. In vivo experiments confirmed that the sensor can accurately distinguish normal tissues and tumor tissues. The proposed sensor provides a novel way to realize multi-parameter monitoring of tumor microenvironment and improve the specificity of tumor detection.

Development of a novel ratiometric fluorescent probe for real-time monitoring of acidic pH and its applications in food samples and biosystem

In this research, a high-efficiency ratiometric fluorescent probe TZTF for sensitive detecting the fluctuations of acidic pH was synthesized. The fluorescent color changed from bright blue to orange in the pH values range from 8.0 to 1.0 with the pKa value of 5.41. Meanwhile, the probe demonstrated excellent selectivity, good anti-interference ability, prominent reversibility, outstanding photostability, and low cytotoxicity. The detection mechanism of TZTF towards acidic pH was verified through 1H NMR analysis and DFT calculation. Additionally, probe TZTF was also applied to evaluate the freshness of meat samples, as the pH value of meat samples may decrease if they are not stored properly, and the subsequent acid-catalyzed denaturation of proteins may pose a threat to human health through the food chain. More importantly, fluorescence imaging experiments confirmed that TZTF is appropriate for real-time tracking of pH variations in living cells and living zebrafish.

Influencing mechanism of farming clams on the CO2 flux from aquaculture ponds: Insights from ecosystem carbon metabolism

Aquaculture ponds have garnered increasing attention for their potential roles in the global carbon cycle within the context of global warming. As a significant co-culture species in mariculture ponds, clams exert a notable impact on CO2 flux across the water-air interface. However, the mechanism underlying this influence is as yet unclear. This study measured the CO2 flux as well as the ecosystem carbon metabolism and environmental physiochemical parameters from four marine polyculture ponds, i.e., the pond containing swimming crabs and kuruma shrimp was referred to as CS, and the other three ponds containing three varying densities of razor clams additionally based on CS were noted as CSB1, CSB2, and CSB3 in order of increasing clam density. All the bi-species and tri-species polyculture ponds acted as atmospheric CO2 sinks during the farming season, with the peak in CSB1 and the lowest in CSB3. Net ecosystem production was a dominant regulator of CO2 uptake, and sediment respiration significantly increased CO2 production and then affected the CO2 flux, contributing 16.7–20.0 % to the ecosystem respiration (ER). Water pH could function as a potentially reliable CO2 flux predictor in the polyculture ponds, while Chl a was an internal driving factor. The polyculture of clams at low density may have exerted a “bottom-up” effect, accelerating nutrient cycling and thus stimulating the planktonic community, gross primary production (GPP), and ER, whereas a high stocking density of clams can have a “top-down” effect that would have the opposite ecological effects through increased predation pressure from clams. Although GPP and ER were simultaneously promoted or inhibited by clams at different stocking densities, the effect on GPP was always greater than that on ER, resulting in the CO2 sink function that the polyculture ponds performed through the water-air interface being strengthened at low clam densities and weakened at high clam densities. Given the good predictive ability of water pH on CO2 flux, monitoring and management of water pH could be an effective way to regulate the CO2 sink function of mariculture ponds.

Smart Dressings and Their Applications in Chronic Wound Management.

During chronic wound healing, the inflammatory phase can endure for extended periods, heavily impeding or halting the process. Regular inspections and dressing changes are crucial. Modern dressings like hydrogels, hydrocolloids, and foam provide protection and an optimal healing environment. However, they have limitations in offering real-time wound bed status and healing rate. Evaluation relies heavily on direct observation, and passive dressings fail to identify subtle healing differences, preventing adaptive adjustments in biological factors and drug concentrations. In recent years, the clinical field recognizes the value of integrating intelligent diagnostic tools into wound dressings. By monitoring biomarkers linked to chronic wounds' inflammatory state, real-time data can be captured, reducing medical interventions and enabling more effective treatment plans. This fosters innovation in chronic wound care. Researchers have developed smart dressings with sensing, active drug delivery, and self-adjustment capabilities. These dressings detect inflammatory markers like temperature, pH, and oxygen content, enhancing drug bioavailability on the wound surface. As wound healing technology evolves, these smart dressings hold immense potential in chronic wound care and treatment. This comprehensive review updates our understanding on the role and mechanism of action of the smart dressings in chronic refractory wounds by summarizing and discussing the latest research progresses, including the intelligent monitoring of wound oxygen content, temperature, humidity, pH, infection, and enzyme kinetics; intelligent drug delivery triggered by temperature, pH, near-infrared, and electricity; as well as the intelligent self-adjustment of pressure and shape. The review also delves into the constraints and future perspectives of smart dressings in clinical settings, thereby advancing the development of smart wound dressings for chronic wound healing and their practical application in clinical practice.

Real-Time pH Sensor in Bacterial Microenvironments Using Liquid Crystal Core-Shell Microspheres.

It is well-known that the bacterial microenvironment imposes restrictions on the growth and behavior of bacteria. The localized monitoring of microenvironmental factors is appreciated when consulting bacterial adaptation and behavior in the presence of chemical or mechanical stimuli. Herein, we developed a novel liquid crystal (LC) biosensor in a microsphere configuration for real-time 3D monitoring of the bacteria microenvironment, which was implemented by a microfluidic chip. As a proof of concept, a LC gel (LC-Gel) microsphere biosensor was prepared and employed in the localized pH changes of bacteria by observing the configuration change of LC under polarized optical microscopy. Briefly, the microsphere biosensor was constructed in core-shell configuration, wherein the core contained LCE7 (a nematic LC) doped with 4-pentylbiphenyl-4'-carboxylic acid (PBA), and the shell encapsulated the bacteria. The protonation of carboxyl functional groups of the PBA induced a change in charge density on the surface of LCE7 and the orientation of E7 molecules, resulting in the transitions of the LC nucleus from axial to bipolar. The developed LC-Gel microspheres pH sensor exhibited its dominant performance on localized pH real-time sensing with a resolution of 0.1. An intriguing observation from the prepared pH biosensor was that the diverse bacteria impelled distinct acidifying or alkalizing effects. Overall, the facile LC-Gel microsphere biosensor not only provides a versatile tool for label-free, localized pH monitoring but also opens avenues for investigating the effects of chemical and mechanical stimuli on cellular metabolism within bacterial microenvironments.

Real-Time Monitoring of Photoinduced pH Jumps by In Situ Rapid-Scan EPR Spectroscopy.

This work represents the first demonstration of monitoring kinetics upon a light-induced pH jump by in situ rapid-scan (RS) electron paramagnetic resonance (EPR) spectroscopy on the millisecond time scale. Here, we focus on the protonation state of an imidazolidine type radical as a pH sensor under visible light irradiation of a merocyanine photoacid in bulk solution. The results highlight the utility of photoacids in combination with pH-sensitive spin probes as an effective tool for the real-time investigation of biochemical mechanisms regulated by changes in the pH value.