A Descriptive Review on the Potential Use of Diatom Biosilica as a Powerful Functional Biomaterial: A Natural Drug Delivery System.

Although various chemically synthesized materials are essential in medicine, food, and agriculture, they can exert unexpected side effects on the environment and human health by releasing certain toxic chemicals. Therefore, eco-friendly and biocompatible biomaterials based on natural resources are being actively explored. Recently, biosilica derived from diatoms has attracted attention in various biomedical fields, including drug delivery systems (DDS), due to its uniform porous nano-pattern, hierarchical structure, and abundant silanol functional groups. Importantly, the structural characteristics of diatom biosilica improve the solubility of poorly soluble substances and enable sustained release of loaded drugs. Additionally, diatom biosilica predominantly comprises SiO2, has high biocompatibility, and can easily hybridize with other DDS platforms, including hydrogels and cationic DDS, owing to its strong negative charge and abundant silanol groups. This review explores the potential applications of various diatom biosilica-based DDS in various biomedical fields, with a particular focus on hybrid DDS utilizing them.

Significance of changes in cavity after treatment in Mycobacterium avium complex pulmonary disease.

Cavities are characteristic radiological features related to increased mycobacterial burden and poor prognosis in Mycobacterium avium complex pulmonary disease (MAC-PD). However, cavity changes following treatment and their clinical implications remain unknown. We aimed to elucidate whether cavity obliteration or reduction in cavity size or wall thickness correlates with microbiological cure. In total, 136 adult patients with cavitary MAC-PD treated for ≥ 6 months between January 1st, 2009, and December 31st, 2021, in a tertiary referral centre in South Korea were enrolled. The cavity with the largest diameter at treatment initiation was tracked for size and thickness changes. Following median treatment of 20.0 months, 74 (54.4%) patients achieved microbiological cure. Cavity obliteration, achieved in 58 (42.6%) patients at treatment completion, was independently associated with microbiological cure. In patients with persistent cavities, size reduction of ≥ 10% was significantly associated with microbiological cure, whereas thickness reduction was not. Five-year mortality rates in patients with cavity obliteration, persistent but reduced cavity, and persistent cavity without shrinkage were 95.6%, 72.1%, and 65.3%, respectively (P < 0.001). In conclusion, cavity obliteration or shrinkage at treatment completion is associated with microbiological cure and reduced mortality in MAC-PD, suggesting that cavity changes could serve as a proxy indicator for treatment response.

Highly enhanced Hg2+ detection using optimized DNA and a double coffee ring effect-based SERS map.

Hg2+ is a highly toxic heavy metal ion that poses serious risks to human health and the environment. Due to its tendency to accumulate, it can easily enter the human body through the food chain, making it crucial to develop detection sensors that mimic real environmental conditions. To achieve this, our study employed a surface-enhanced Raman scattering (SERS) sensor using two strategies. First, we designed a highly selective probe by optimizing the probe and reporter DNA strands to bind Hg2+ within a thymine-thymine mismatch. Second, we used the double coffee ring effect to concentrate the optimized probe DNA. These two strategies greatly enhanced the SERS signal, resulting in a sensor with exceptional sensitivity, a low detection limit of 208.71 fM, and superior selectivity for Hg2+. The practical application of the sensor was demonstrated by successfully detecting Hg2+ in drinking water, tap water, canned tuna, and tuna sashimi. Additionally, the experimental results were presented in a pizza-shaped SERS mapping image, allowing users to estimate Hg2+ concentrations through color, providing a user-friendly and intuitive method for data comprehension and analysis. Our study presents a promising approach for sensitive and reliable Hg2+ detection, with potential implications for environmental monitoring and food safety.

Excited-State Dynamics of a Bright Fluorescent Dye with Precise Control of Emission Color Using Acid-Base Equilibrium, Intramolecular Charge Transfer, and Host-Guest Chemistry.

A fluorescent dye, a dithiophene-conjugated benzothiazole derivative (DTBz), was prepared to have high fluorescence emission quantum yields (ΦF) across various organic solvents. Its emission color modulation, from bright blue to deep red, was achieved through intramolecular charge transfer (ICT), acid-base equilibrium, and host-guest chemistry. Although it exhibits a weak solvatochromic effect, DTBz exhibited a bright fluorescence emission around 480 nm upon excitation at 390 nm in most solvents. In polar solvents, such as MeOH (methanol), EtOH (ethanol), DMF (N,N-dimethylforamide), and DMSO (dimethyl sulfoxide), an additional ICT emission band emerged around 640 nm, notably intense in DMSO, resulting in a bright greenish-white emission (ΦF = 0.67). The addition of 1,8-diazabicyclo[5,4.0]undec-7-ene (DBU) altered emission characteristics, reducing emission from the local excited (LE) state and enhancing ICT state emission. The degree of emission spectral change saturation with DBU addition varied with the solvent nature. Polar solvents with high dielectric constants, like DMSO and DMF, saw a complete disappearance of LE state emission with 5 equiv of DBU, resulting in a deep red emission (ΦFs of 0.53 and 0.48, respectively). Femtosecond transient absorption spectroscopy and time-resolved photoluminescence measurements elucidated the excited-state dynamics, revealing a long-lived excited state (τ-H = 10.3 ns) at a lower energy emission (640 nm), identified as DTBz-*, supported by transient absorption spectra analysis. Further analysis, including time-resolved fluorescence decay measurements and time-dependent density-functional theory (TD-DFT) calculations, underscored the role of deprotonation of DTBz's hydroxyl group in promoting the ICT process. The CIE coordination plot demonstrated wide linear emission color changes upon successive DBU additions in all solvents, while emission color precision was achieved through host-guest chemistry. Emission changes induced by DBU were reverted to the original state upon beta-cyclodextrin (ß-CD) addition, with the 1H NMR study revealing the competition between acid-base equilibrium and host-guest complex formation as the cause of emission color change.

An updated review on the development of a nanomaterial-based field-effect transistor-type biosensors to detect exosomes for cancer diagnosis.

Cancer, a life-threatening genetic disease caused by abnormalities in normal cell growth regulatory functions, poses a significant challenge that current medical technologies cannot fully overcome. The current desired breakthrough is to diagnose cancer as early as possible and increase survival rates through treatments tailored to the prognosis and appropriate follow-up. From a perspective that reflects this contemporary paradigm of cancer diagnostics, exosomes are emerging as promising biomarkers. Exosomes, serving as mobile biological information repositories of cancer cells, have been known to create a microtumor environment in surrounding cells, and significant insight into the clinical significance of cancer diagnosis targeting them has been reported. Therefore, there are growing interests in constructing a system that enables continuous screening with a focus on patient-friendly and flexible diagnosis, aiming to improve cancer screening rates through exosome detection. This review focuses on a proposed exosome-embedded biological information-detecting platform employing a field-effect transistor (FET)-based biosensor that leverages portability, cost-effectiveness, and rapidity to minimize the stages of sacrifice attributable to cancer. The FET-applied biosensing technique, stemming from variations in an electric field, is considered an early detection system, offering high sensitivity and a prompt response frequency for the qualitative and quantitative analysis of biomolecules. Hence, an in-depth discussion was conducted on the understanding of various exosome-based cancer biomarkers and the clinical significance of recent studies on FET-based biosensors applying them.

Self-crossing hyaluronic acid filler with combination use of polydioxanone thread in minipig model.

INTRODUCTION: The advances of self-crossing hyaluronic acid (SC-HA) fillers combination use with polydioxanone thread in minipigs were examined for compatibility, effectiveness, and immune response. MATERIALS AND METHODS: A 12-week experiment was conducted using 6 minipigs (3 male and 3 female each) to evaluate the effects of SC-HA filler. The molecular weight of SC-HA filler was fixed at 200 kDa and alternative storage modulus of G80, G250, and G500 were examined. The procedure involved injecting SC-HA filler and polydioxanone threads into the skin tissue of anesthetized minipigs, and tissue sampling after 1 month (three minipigs), and 3 months (three minipigs) for histological staining and analysis. The immune reaction was observed during the experiment. RESULTS: The practitioner reported it was easy to inject the SC-HA filler in combination with polydioxanone threads. All four storage modulus of SC-HA fillers were injectable within the polydioxanone thread containing cannula. Also, during the procedure, there were no immune responses at the treated sites. The results of the histological tissue examination confirmed that there was no chemical interaction between SC-HA filler and the existing polydioxanone thread, and it was observed that SC-HA filler was more uniformly distributed within the tissue with lower storage modulus, resulting in a higher production of collagen in the surrounding filler. When combined with scaffold polydioxanone thread, the scaffold polydioxanone thread helped spread the filler evenly, resulting in a more evenly distributed collagen around the filler. CONCLUSION: Today, the combination therapy of filler and polydioxanone thread in one procedure is challenging due to the high viscosity of conventional fillers. However, this study confirmed that combination therapy of filler and polydioxanone thread is possible with SC-HA fillers. Additionally, it was found that polydioxanone thread does not seem to interfere with the crosslinking reaction of SC-HA filler, and if used with a higher pH of polydioxanone, it may enhance the cross-linking reaction and achieve a higher viscosity value. Finally, the study resulted in the idea of concrete as SC-HA filler and reinforcing rod for polydioxanone thread.

High-resolution 3-D scanning electron microscopy (SEM) images of DOTTM polynucleotides (PN): Unique scaffold characteristics and potential applications in biomedicine.

INTRODUCTION: Polynucleotides (PN) are becoming more prominent in aesthetic medicine. However, the structural characteristics of PN have not been published and PN from different companies may have different structural characteristics. This study aimed to elucidate the structural attributes of DOT™ PN and distinguish differences with polydeoxyribonucleotides (PDRN) using high-resolution scanning electron microscopy (SEM) imaging. MATERIALS AND METHODS: DOT™ PN was examined using a Quanta 3-D field emission gun (FEG) Scanning Electron Microscope (SEM). Sample preparation involved cryogenic cooling, cleavage, etching, and metal coating to facilitate high-resolution imaging. Cryo-FIB/SEM techniques were employed for in-depth structural analysis. RESULTS: PDRN exhibited an amorphous structure without distinct features. In contrast, DOT™ PN displayed well-defined polyhedral shapes with smooth, uniformly thick walls. These cells were empty, with diameters ranging from 3 to 8 micrometers, forming a seamless tessellation pattern. DISCUSSION: DOT™ PN's distinct geometric tessellation design conforms to the principles of biotensegrity, providing both structural reinforcement and integrity. The presence of delicate partitions and vacant compartments hints at possible uses in the field of pharmaceutical delivery systems. Within the realms of beauty enhancement and regenerative medicine, DOT™ PN's capacity to bolster cell growth and tissue mending could potentially transform approaches to rejuvenation treatments. Its adaptability becomes apparent when considering its contributions to drug administration and surgical procedures. CONCLUSION: This study unveils the intricate structural scaffold features of DOT™ PN for the first time, setting it apart from PDRN and inspiring innovation in biomedicine and materials science. DOT™ PN's unique attributes open doors to potential applications across healthcare and beyond.

Highly Sensitive and Wide-Range Detection of Thiabendazole via Surface-Enhanced Raman Scattering Using Bimetallic Nanoparticle-Functionalized Nanopillars.

Thiabendazole (TBZ) is a benzimidazole; owing to its potent antimicrobial properties, TBZ is extensively employed in agriculture as a fungicide and pesticide. However, TBZ poses environmental risks, and excessive exposure to TBZ through various leakage pathways can cause adverse effects in humans. Therefore, a method must be developed for early and sensitive detection of TBZ over a range of concentrations, considering both human and environmental perspectives. In this study, we used silver nanopillar structures (SNPis) and Au@Ag bimetallic nanoparticles (BNPs) to fabricate a BNP@SNPi substrate. This substrate exhibited a broad reaction surface with significantly enhanced surface-enhanced Raman scattering hotspots, demonstrating excellent Raman performance, along with high reproducibility, sensitivity, and selectivity for TBZ detection. Ultimately, the BNP@SNPi substrate successfully detected TBZ across a wide concentration range in samples of tap water, drinking water, juice, and human serum, with respective limits of detection of 146.5, 245.5, 195.6, and 219.4 pM. This study highlights BNP@SNPi as a promising sensor platform for TBZ detection in diverse environments and contributes to environmental monitoring and bioanalytical studies.

Is multiple wavelength diode laser for facial contouring safe?

The multiple wavelength diode laser (MWDL) is a sophisticated device designed to target deeper skin layers by emitting various wavelengths. Its unique feature is the ability to deliver heat to specific depths within the tissue using different wavelengths while simultaneously cooling the skin surface. Recent research by Choi et al. suggests that wavelengths of 755 and 810 nm can induce carbonization in hair follicles, while the 1064 nm wavelength penetrates deeper into tissues. MWDL has been proposed for fat redistribution in aging, but concerns have been raised regarding ocular safety and potential tissue damage, particularly when used near the eyes. Studies have shown ocular injuries during cosmetic laser procedures, emphasizing the need for robust ocular protection and safety protocols. Additionally, there are reports of internal ischemic necrosis and burns, highlighting the importance of precise energy settings and parameter management. While MWDL shows promise, further research and comprehensive guidelines are needed to ensure safe and effective usage in clinical practice.

Two novel glutathione S-transferase (GST) genes in the toxic marine dinoflagellate Alexandrium pacificum and their transcriptional responses to environmental contaminants.

The present study identified two novel glutathione S-transferase (GST) genes from the toxic dinoflagellate Alexandrium pacificum and examined their molecular characteristics and transcriptional responses to algicides and environmental contaminants. Bioinformatic analysis revealed that both ApGSTs are cytosolic, belonging to the chi-like class (ApGST1) and an undefined class (ApGST2). The overall expression of ApGSTs showed similar patterns depending on the exposed contaminants, while they were differently regulated by polychlorinated biphenyl (PCB). Copper treatments (CuCl2 and CuSO4) did not significantly induce the expression of ApGSTs. The highest up-regulations of ApGST1 and ApGST2 were under 6-h treatments of 0.10 and 0.50 mg L-1 NaOCl. Interestingly, only ApGST1 increased significantly after 0.10, 0.50, and 1.00 mg L-1 of PCB exposure (6 h). Intracellular reactive oxygen species (ROS) increased considerably under NaOCl; however, it was not significantly higher in the PCB-treated cells. GST activity was increased by NaOCl and PCB treatments, but only PCB caused apoptosis. These results suggest that GSTs are involved in the first line of phase II detoxification, protecting dinoflagellate cells against oxidative damage.

Influence of HCl Concentration on Corrosion Behavior between Au or Cu Bonding Wires and the Bond Pad for Semiconductor Packaging.

Wire bonding, one of the methods for electrically connecting a semiconductor chip with a substrate, involves attaching thin metal wires to pads. It is the oldest electrical connection method that exhibits high compatibility with other processes. The metal wires used for electrical connection in wire bonding are mainly made of Au, Cu, and Ag. After the wire bonding, molding is performed using the epoxy molding compound (EMC). However, EMC inevitably contains ions such as halogen elements. In addition, it absorbs moisture due to its hydrophilicity, creating a corrosive environment with electrolytes. In this study, we evaluated the influence of hydrochloric acid concentration on corrosion behavior between Au or Cu bonding wires and sputtered Al bond pads. The electrochemical factors such as corrosion potential difference (ΔE), galvanic corrosion current density (ig), and anodic and cathodic Tafel slopes were found to influence galvanic corrosion behavior. Galvanic corrosion tendency in first bond and second bond areas of PCB unit specimen was confirmed.

Retention of Intrinsic Photophysical Properties of Porphyrin Building Blocks in 3D Organic Frameworks through Magic Angle Alignment.

Construction of three-dimensional (3D) frameworks maintaining intrinsic photophysical properties of monomeric building blocks is difficult and challenging due to the existence of various molecular interactions, such as metal-organic and π-π interactions. A 3D hydrogen-bonded organic framework (YSH-1Zn) with permanent porosity was constructed using a porphyrin having six carboxylic acid groups (1Zn). Brunauer-Emmett-Teller surface area measurement indicated that YSH-1Zn has a porous structure with a surface area of 392 m2/g. Single-crystal X-ray diffraction analysis revealed that 1Zn creates a 5-fold interwoven 3D network structure adopting a monoclinic system with a space group of P21/c. Each 1Zn within a single crystal exhibits parallel alignment with a slip-stack angle of 54.6°, in good agreement with the magic angle. Although the center-to-center distance of the nearest zinc atoms in YSH-1Zn is only 5.181 Å, the UV/vis absorption and fluorescence emission of YSH-1Zn are not different from those of 1Zn, indicating the absence of an interaction between excitons. Due to the magic angle alignment of 1Zn, the fluorescence lifetime, decay profiles, and quantum yield remained uniform even in the solid state.

Association of Bypass Surgery and Mortality in Moyamoya Disease.

Background Patients with moyamoya disease (MMD) have a high risk of stroke or death. We investigated whether extracranial to intracranial bypass surgery can reduce mortality by preventing strokes in patients with MMD. Methods and Results This nationwide retrospective cohort study encompassed patients with MMD registered under the Rare Intractable Diseases program via the Relieved Co-Payment Policy between 2006 and 2019, using the Korean National Health Insurance Service database. Following a 4-year washout period, landmark analyses were employed to assess mortality and stroke occurrence between the bypass surgery group and the nonsurgical control group at specific time points postindex date (1 month and 3, 6, 12, and 36 months). The study included 18 480 patients with MMD (mean age, 40.7 years; male to female ratio, 1:1.86) with a median follow-up of 5.6 years (interquartile range, 2.5-9.3; mean, 6.1 years [SD, 4.0 years]). During 111 775 person-years of follow-up, 265 patients in the bypass surgery group and 1144 patients in the nonsurgical control group died (incidence mortality rate of 618.1 events versus 1660.3 events, respectively, per 105 person-years). The overall adjusted hazard ratio (HR) revealed significantly lower all-cause mortality in the bypass surgery group from the 36-month landmark time point, for any stroke mortality from 3- and 6-month landmark time points, and for hemorrhagic stroke mortality from the 6-month landmark time point. Furthermore, the overall adjusted HRs for hemorrhagic stroke occurrence were beneficially maintained from all 5 landmark time points in the bypass surgery group. Conclusions Bypass surgery in patients with MMD was associated with a lower risk of all-cause and hemorrhagic stroke mortality and hemorrhagic stroke occurrence compared with nonsurgical control.

Recent Progress in Diatom Biosilica: A Natural Nanoporous Silica Material as Sustained Release Carrier.

A drug delivery system (DDS) is a useful technology that efficiently delivers a target drug to a patient's specific diseased tissue with minimal side effects. DDS is a convergence of several areas of study, comprising pharmacy, medicine, biotechnology, and chemistry fields. In the traditional pharmacological concept, developing drugs for disease treatment has been the primary research field of pharmacology. The significance of DDS in delivering drugs with optimal formulation to target areas to increase bioavailability and minimize side effects has been recently highlighted. In addition, since the burst release found in various DDS platforms can reduce drug delivery efficiency due to unpredictable drug loss, many recent DDS studies have focused on developing carriers with a sustained release. Among various drug carriers, mesoporous silica DDS (MS-DDS) is applied to various drug administration routes, based on its sustained releases, nanosized porous structures, and excellent solubility for poorly soluble drugs. However, the synthesized MS-DDS has caused complications such as toxicity in the body, long-term accumulation, and poor excretion ability owing to acid treatment-centered manufacturing methods. Therefore, biosilica obtained from diatoms, as a natural MS-DDS, has recently emerged as an alternative to synthesized MS-DDS. This natural silica carrier is an optimal DDS platform because culturing diatoms is easy, and the silica can be separated from diatoms using a simple treatment. In this review, we discuss the manufacturing methods and applications to various disease models based on the advantages of biosilica.

Extended-Gate Field-Effect Transistor Consisted of a CD9 Aptamer and MXene for Exosome Detection in Human Serum.

Cancer progresses silently to the terminal stage of the impossible operable condition. There are many limitations in the treatment options of cancer, but diagnosis in an early stage can improve survival rates and low recurrence. Exosomes are the biomolecules released from cancer cells and are promising candidates for clinical diagnosis. Among them, the cluster of differentiation 9 (CD9) protein is an important exosomal biomarker that can be used for exosome determination. Therefore, here, a CD9 aptamer was first synthesized and applied to an extended-gate field-effect transistor (EGFET)-type biosensor containing a disposable sensing membrane to suggest the possibility of detecting exosomes in a clinical environment. Systematically evaluating ligands using the exponential enrichment (SELEX) technique was performed to select nucleic acid sequences that can specifically target the CD9 protein. Exosomes were detected according to the electrical signal changes on a membrane, which is an extended gate using an Au microelectrode. The fabricated biosensor showed a limit of detection (LOD) of 10.64 pM for CD9 proteins, and the detection range was determined from 10 pM to 1 µM in the buffer. In the case of the clinical test, the LOD and detection ranges of exosomes in human serum samples were 6.41 × 102 exosomes/mL and 1 × 103 to 1 × 107 exosomes/mL, respectively, showing highly reliable results with low error rates. These findings suggest that the proposed aptasensor can be a powerful tool for a simple and early diagnosis of exosomes.

Anatomical proposal of local anesthesia injection for median nerve block in treating hyperhidrosis with botulinum neurotoxin.

INTRODUCTION: Hyperhidrosis, causing excessive sweat, can be treated with Botulinum neurotoxin injection. Botulinum toxin, an effective and safe treatment for hyperhidrosis, unfortunately involves significant pain due to multiple injections. This study aims to propose a more efficient and less painful approach to nerve blocks for relief, by identifying optimal injection points to block the median nerve, thereby enhancing palmar hyperhidrosis treatment. METHODS: This study, involving 52 Korean cadaver arms (mean age 73.5 years), measured the location of the median nerve relative to the transverse line at the pisiform level to establish better nerve block injection sites. RESULTS: In between the extensor carpi radialis and palmaris longus, the median nerve was located at an average distance of 47.39 ± 6.43 mm and 29.39 ± 6.43 mm from the transverse line at the pisiform level. DISCUSSION: To minimize discomfort preceding the botulinum neurotoxin injection, we recommend the optimal injection site for local anesthesia to be located 4 cm distal to the transverse line of the pisiform, within the tendons of the palmaris longus and flexor carpi radialis muscles.

Influence of Cr Content on the High-Temperature Oxidation Behavior and Mechanism of Low-Alloy Steels.

The high-temperature oxidation behavior of low-carbon steel (AISI 1015, AISI 8617, AISI 4115) was investigated over the temperature range from 600 to 1000 °C in humid air containing 25% water vapor. Mass gain of oxidation measurement was performed to study the oxidation kinetics. The microstructure, thickness, and composition of the oxide scale formed were investigated via optical microscope (OM), scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and electron probe microanalyzer (EPMA). The oxidation process was performed from 2 to 100 min. As the oxidation time increased, the trend of mass gain per unit area switched from a linear to a parabolic law, regardless of the steel grade used. As the chromium content increased, the duration of time during which the oxidation rate followed a linear relationship decreased. In the low-alloy steel with higher chromium content, the thickness of the mixed oxide layer containing Cr increased and the oxidation rate decreased at all oxidation temperatures.

Prognostic serum biomarkers in non-tuberculous mycobacterial pulmonary disease.

Increased serum C-reactive protein (CRP) levels at the time of diagnosis predicted worse prognosis in patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD). Approximately one-quarter of the patients with NTM-PD had higher than normal CRP levels, and this elevation led to a higher risk of death.