Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.

Purpose: Although some medications trigger the worsening of myasthenia gravis (MG), their clinical influence on patients with MG has not been significantly evaluated. We aimed to investigate whether the risk of clinical worsening of MG increases after administering cautionary drugs in patients with MG. Materials and Methods: This retrospective case-control study was based on the medical records of patients diagnosed with MG between 2007 and 2020. We analyzed the risk of MG worsening in patients exposed to cautionary drugs during the risk period, defined as 6 months from the first exposure to cautionary drugs. The risk of MG worsening in the exposed patients was compared to that in the non-exposed patients, who were individually matched in a 1:1 ratio with exposed cases for sex, age, thymoma, and autoantibodies. Results: Of the 2002 patients diagnosed with MG, 552 (27.6%) were exposed to cautionary drugs. Neuromuscular blocking agents (320 patients) and beta blockers (66123 person-days) were the most frequently prescribed medications. After exact matching, 220 exposed and 220 non-exposed patients were enrolled. The incidence rate of clinical worsening during the risk period was significantly higher in the exposed patients than in the non-exposed patients (odds ratio=4.09; 95% confidence interval, 1.88–8.90;p<0.001). Clinical worsening was observed in 31 (14.1%) of the exposed patients and in 8 (3.6%) of the non-exposed patients. Conclusion The administration of cautionary drugs increased the risk of clinical worsening in patients with MG. Clinicians should be aware of this risk when cautionary drugs need to be administered.

While glutamate, a key neurotransmitter in the central nervous system, is fundamental to neuronal viability and normal brain function, its excessive accumulation leads to oxidative stress, contributing to neuronal damage and neurodegenerative diseases. In this study, we investigated the effect of β-lapachone (β-Lap), a naturally occurring naphthoquinone, on glutamate-induced injury in HT22 cells and explored the underlying mechanism involved. Our results show that β-Lap significantly improved cell viability in a dose-dependent manner. Additionally, β-Lap exhibited a significant antioxidant activity, reducing intracellular reactive oxygen species levels and restoring glutathione levels. The antioxidant capacity of β-Lap was further demonstrated through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assays. Western blot analysis revealed that β-Lap upregulated brain-derived neurotrophic factor (BDNF) and promoted the phosphorylation of tropomyosin receptor kinase B (TrkB), extracellular signal-regulated kinase (ERK), and cAMP response elementbinding protein (CREB), which were downregulated by glutamate. Furthermore, β-Lap enhanced the cellular antioxidant molecules, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). In conclusion, β-Lap can protect HT22 cells against glutamate-induced injury by activating the BDNF/TrkB/ERK/CREB and ERK/Nrf2/HO-1 signaling pathways, suggesting its therapeutic potential for neurodegenerative diseases.

Purpose: Although some medications trigger the worsening of myasthenia gravis (MG), their clinical influence on patients with MG has not been significantly evaluated. We aimed to investigate whether the risk of clinical worsening of MG increases after administering cautionary drugs in patients with MG. Materials and Methods: This retrospective case-control study was based on the medical records of patients diagnosed with MG between 2007 and 2020. We analyzed the risk of MG worsening in patients exposed to cautionary drugs during the risk period, defined as 6 months from the first exposure to cautionary drugs. The risk of MG worsening in the exposed patients was compared to that in the non-exposed patients, who were individually matched in a 1:1 ratio with exposed cases for sex, age, thymoma, and autoantibodies. Results: Of the 2002 patients diagnosed with MG, 552 (27.6%) were exposed to cautionary drugs. Neuromuscular blocking agents (320 patients) and beta blockers (66123 person-days) were the most frequently prescribed medications. After exact matching, 220 exposed and 220 non-exposed patients were enrolled. The incidence rate of clinical worsening during the risk period was significantly higher in the exposed patients than in the non-exposed patients (odds ratio=4.09; 95% confidence interval, 1.88–8.90;p<0.001). Clinical worsening was observed in 31 (14.1%) of the exposed patients and in 8 (3.6%) of the non-exposed patients. Conclusion The administration of cautionary drugs increased the risk of clinical worsening in patients with MG. Clinicians should be aware of this risk when cautionary drugs need to be administered.

While glutamate, a key neurotransmitter in the central nervous system, is fundamental to neuronal viability and normal brain function, its excessive accumulation leads to oxidative stress, contributing to neuronal damage and neurodegenerative diseases. In this study, we investigated the effect of β-lapachone (β-Lap), a naturally occurring naphthoquinone, on glutamate-induced injury in HT22 cells and explored the underlying mechanism involved. Our results show that β-Lap significantly improved cell viability in a dose-dependent manner. Additionally, β-Lap exhibited a significant antioxidant activity, reducing intracellular reactive oxygen species levels and restoring glutathione levels. The antioxidant capacity of β-Lap was further demonstrated through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assays. Western blot analysis revealed that β-Lap upregulated brain-derived neurotrophic factor (BDNF) and promoted the phosphorylation of tropomyosin receptor kinase B (TrkB), extracellular signal-regulated kinase (ERK), and cAMP response elementbinding protein (CREB), which were downregulated by glutamate. Furthermore, β-Lap enhanced the cellular antioxidant molecules, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). In conclusion, β-Lap can protect HT22 cells against glutamate-induced injury by activating the BDNF/TrkB/ERK/CREB and ERK/Nrf2/HO-1 signaling pathways, suggesting its therapeutic potential for neurodegenerative diseases.

Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.

Purpose: Although some medications trigger the worsening of myasthenia gravis (MG), their clinical influence on patients with MG has not been significantly evaluated. We aimed to investigate whether the risk of clinical worsening of MG increases after administering cautionary drugs in patients with MG. Materials and Methods: This retrospective case-control study was based on the medical records of patients diagnosed with MG between 2007 and 2020. We analyzed the risk of MG worsening in patients exposed to cautionary drugs during the risk period, defined as 6 months from the first exposure to cautionary drugs. The risk of MG worsening in the exposed patients was compared to that in the non-exposed patients, who were individually matched in a 1:1 ratio with exposed cases for sex, age, thymoma, and autoantibodies. Results: Of the 2002 patients diagnosed with MG, 552 (27.6%) were exposed to cautionary drugs. Neuromuscular blocking agents (320 patients) and beta blockers (66123 person-days) were the most frequently prescribed medications. After exact matching, 220 exposed and 220 non-exposed patients were enrolled. The incidence rate of clinical worsening during the risk period was significantly higher in the exposed patients than in the non-exposed patients (odds ratio=4.09; 95% confidence interval, 1.88–8.90;p<0.001). Clinical worsening was observed in 31 (14.1%) of the exposed patients and in 8 (3.6%) of the non-exposed patients. Conclusion The administration of cautionary drugs increased the risk of clinical worsening in patients with MG. Clinicians should be aware of this risk when cautionary drugs need to be administered.

Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.

While glutamate, a key neurotransmitter in the central nervous system, is fundamental to neuronal viability and normal brain function, its excessive accumulation leads to oxidative stress, contributing to neuronal damage and neurodegenerative diseases. In this study, we investigated the effect of β-lapachone (β-Lap), a naturally occurring naphthoquinone, on glutamate-induced injury in HT22 cells and explored the underlying mechanism involved. Our results show that β-Lap significantly improved cell viability in a dose-dependent manner. Additionally, β-Lap exhibited a significant antioxidant activity, reducing intracellular reactive oxygen species levels and restoring glutathione levels. The antioxidant capacity of β-Lap was further demonstrated through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging assays. Western blot analysis revealed that β-Lap upregulated brain-derived neurotrophic factor (BDNF) and promoted the phosphorylation of tropomyosin receptor kinase B (TrkB), extracellular signal-regulated kinase (ERK), and cAMP response elementbinding protein (CREB), which were downregulated by glutamate. Furthermore, β-Lap enhanced the cellular antioxidant molecules, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). In conclusion, β-Lap can protect HT22 cells against glutamate-induced injury by activating the BDNF/TrkB/ERK/CREB and ERK/Nrf2/HO-1 signaling pathways, suggesting its therapeutic potential for neurodegenerative diseases.

Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.