Long-term adjuvant metronomic chemotherapy in a dog with recurrent maxillofacial osteosarcoma.

Osteosarcoma (OSA) is the most common malignant bone tumour in dogs; however, OSA of the maxilla is uncommon compared to appendicular OSA. Oral melanoma also commonly occurs in dogs with frequent distant metastasis. The role of adjuvant chemotherapy has been questioned in maxillary OSA and melanoma. A 17-year-old English Cocker Spaniel was referred with a growing mass on the right maxilla and a right lower lip mass. Osteosarcoma was diagnosed after partial maxillectomy, and the right lower lip mass was diagnosed as oral melanoma. Metronomic chemotherapy (MC) was performed, and the number of doses was tapered due to side effects at 5 weeks after initiation of MC. After 130 weeks of MC, chemotherapy was suspended due to kidney disease. After the suspension of chemotherapy, findings suggesting recurrence and metastasis were detected. The dog suddenly died 193 weeks after surgery, which was 8-14 times longer than the expected survival time. To the best of our knowledge, this is the first case report of successful long-term combination therapy, including surgery and MC, in a dog with maxillary OSA and lip melanoma. Our results show that the survival time can be greatly extended if MC is performed with proper management.

Acute intoxication due to Wisteria floribunda seed in seven young children.

BACKGROUND: Wisteria floribunda is a vine commonly found in Korea, Japan, and the USA. The objective of this observational study was to assess the toxicity of W. floribunda seeds in young children. METHODS: Of 28 children in a kindergarten who participated in a field trip, seven ingested W. floribunda seeds: six half of the seed and one a whole seed. These seven children were admitted to the Gachon University Gil Medical Center in Incheon, Korea. RESULTS: All of the children had vomiting within 4 h of ingesting the W. floribunda seed; the child who ingested a whole seed began to vomit 2 h after ingestion. By 5 h after ingestion, they all complained of abdominal pain and one child was lethargic. Leukocytosis was observed in all of the children. Abdominal pain and vomiting subsided in all of the children within 2 days after admission. The average duration of hospitalization was 3.1 days. CONCLUSIONS: W. floribunda seed ingestion induced gastrointestinal and neurologic symptoms in these young children. Given that the onset of vomiting was earlier in the child who ingested a whole seed than in the children who had ingested only a half, the amount of ingested seeds may be associated with the severity of the symptoms. Ingestion of half a raw W. floribunda seed can cause gastrointestinal symptoms in young children and even result in hospitalization.

A mononuclear non-heme high-spin iron(III)-hydroperoxo complex as an active oxidant in sulfoxidation reactions.

We report the first direct experimental evidence showing that a high-spin iron(III)-hydroperoxo complex bearing an N-methylated cyclam ligand can oxidize thioanisoles. DFT calculations showed that the reaction pathway involves heterolytic O-O bond cleavage and that the choice of the heterolytic pathway versus the homolytic pathway is dependent on the spin state and the number of electrons in the d(xz) orbital of the Fe(III)-OOH species.

Adequacy of the examination-based licensing system and a training-based licensing system for midwifery license according to changes in childbirth medical infrastructure in Korea: a surveybased descriptive study

PURPOSE: The number of Korean midwifery licensing examination applicants has steadily decreased due to the low birth rate and lack of training institutions for midwives. This study aimed to evaluate the adequacy of the examination-based licensing system and the possibility of a training-based licensing system. METHODS: A survey questionnaire was developed and dispatched to 230 professionals from December 28, 2022 to January 13, 2023, through an online form using Google Surveys. Descriptive statistics were used to analyze the results. RESULTS: Responses from 217 persons (94.3%) were analyzed after excluding incomplete responses. Out of the 217 participants, 198 (91.2%) agreed with maintaining the current examination-based licensing system; 94 (43.3%) agreed with implementing a training-based licensing system to cover the examination costs due to the decreasing number of applicants; 132 (60.8%) agreed with establishing a midwifery education evaluation center for a training-based licensing system; 163 (75.1%) said that the quality of midwifery might be lowered if midwives were produced only by a training-based licensing system, and 197 (90.8%) said that the training of midwives as birth support personnel should be promoted in Korea. CONCLUSION: Favorable results were reported for the examination-based licensing system; however, if a training-based licensing system is implemented, it will be necessary to establish a midwifery education evaluation center to manage the quality of midwives. As the annual number of candidates for the Korean midwifery licensing examination has been approximately 10 in recent years, it is necessary to consider more actively granting midwifery licenses through a training-based licensing system.

Phosphorylation of α-synuclein is crucial in compensating for proteasomal dysfunction.

α-Synuclein can be degraded by both the ubiquitin-proteasomal system and the chaperone-lysosomal system. However, the switching mechanism between the two pathways is not clearly understood. In our study, we investigated the mutual association between the binding of α-synuclein to heat shock cognate 70 and the lysosomal translocation of α-synuclein. Tyrosine phosphorylation of Y136 on α-synuclein increased when it bound to heat shock protein 70. We also found that tyrosine phosphorylation of α-synuclein can be regulated by focal adhesion kinase pp125 and protein tyrosine phosphatase 1B. Furthermore, protein tyrosine phosphatase 1B inhibitor protected dopaminergic neurons against cell death and rescued rotarod performance in a Parkinson's disease animal model. This study provides evidence that the regulation of Y136 phosphorylation of α-synuclein can improve behavioral performance and protect against neuronal death by promoting the turnover of lysosomal degradation of α-synuclein. As a result, protein tyrosine phosphatase 1B inhibitor may be used as a potential therapeutic agent against Parkinson's disease.

Factors influencing quality of life in low-income women with young children in Korea: a cross-sectional study.

Purpose: This study aimed to investigate the effects of health-promoting behaviors (HPB), marital intimacy, and parenting stress on the quality of life (QoL) of low-income women with young children in Korea, an underserved group. Methods: This cross-sectional survey employed a descriptive correlational design. Using convenience sampling, 123 low-income women with children younger than 6 years were recruited from 14 health and community centers in Jeonju, Korea, from June 2020 to May 2021. Participants completed a questionnaire on QoL, HPB, marital intimacy, and parenting stress. Data were analyzed using descriptive statistics, independent t-test, analysis of variance, Pearson correlation, and hierarchical regression analysis. Results: Participants, who were on average 37.41±3.65 years old and had 1 to 2 children (n=98, 79.7%), reported a mid-level (3.14 out of 1-5) of QoL. Marital intimacy (ß=.38, p<.001) was the most influential factor on the QoL of low-income women with young children. In descending order, HPB (ß=.35, p<.001) and non-employment status (ß=-.21, p=.003) had a significant influence on QoL (F=15.64, p<.001), and the overall explanatory power was 49.0%. Conclusion: Considering the mid-level QoL of low-income women with young children, programs aimed at improving the QoL of low-income women need to promote marital intimacy and maintain HPB, while considering their employment status. Strategies that include couple counseling, health care to encourage healthy lifestyles, and reemployment education are needed.

Pyruvate Prevents Dopaminergic Neurodegeneration and Motor Deficits in the 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine Model of Parkinson's Disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the selective loss of dopamine(DA)rgic neurons in the substantia nigra of the midbrain, and primarily causes motor symptoms. While the pathological cause of PD remains uncertain, oxidative damage, neuroinflammation, and energy metabolic perturbation have been implicated. Pyruvate has been shown neuroprotective in animal models for many neurological disorders, presumably owing to its potent anti-oxidative, anti-inflammatory, and energy metabolic properties. We therefore investigated whether exogenous pyruvate could also protect nigral DA neurons from degeneration and reverse the associated motor deficits in an animal model of PD using the DA neuron-specific toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). MPTP (20 mg/kg) was injected four times every 2 h into the peritoneum of mice, which resulted in a massive loss of DA neurons as well as an increase in neuronal death and cytosolic labile zinc overload. There were rises in inflammatory and oxidative responses, a drop in the striatal DA level, and the emergence of PD-related motor deficits. In comparison, when sodium pyruvate was administered intraperitoneally at a daily dose of 250 mg/kg for 7 days starting 2 h after the final MPTP treatment, significant relief in the MPTP-induced neuropathology, neurodegeneration, DA depletion, and motor symptoms was observed. Equiosmolar dose of NaCl had no neuroprotective effect, and lower doses of sodium pyruvate did not have any statistically significant effects. These findings suggest that pyruvate has therapeutic potential for the treatment of PD and related neurodegenerative diseases.

Clusterin Binding Modulates the Aggregation and Neurotoxicity of Amyloid-ß(1-42).

Alzheimer's disease (AD) is the most common neurodegenerative disorder characterized by the accumulation of amyloid-ß (Aß) aggregates in the brain. Clusterin (CLU), also known as apolipoprotein J, is a potent risk factor associated with AD pathogenesis, in which Aß aggregation is essentially involved. We observed close colocalization of CLU and Aß(1-42) (Aß42) in parenchymal amyloid plaques or vascular amyloid deposits in the brains of human amyloid precursor protein (hAPP)-transgenic Tg2576 mice. Therefore, to elucidate the binding interaction between CLU and Aß42 and its impact on amyloid aggregation and toxicity, the two synthetic proteins were incubated together under physiological conditions, and their structural and morphological variations were investigated using biochemical, biophysical, and microscopic analyses. Synthetic CLU spontaneously bound to different possible variants of Aß42 aggregates with very high affinity (Kd = 2.647 nM) in vitro to form solid CLU-Aß42 complexes. This CLU binding prevented further aggregation of Aß42 into larger oligomers or fibrils, enriching the population of smaller Aß42 oligomers and protofibrils and monomers. CLU either alleviated or augmented Aß42-induced cytotoxicity and apoptosis in the neuroblastoma-derived SH-SY5Y and N2a cells, depending on the incubation period and the molar ratio of CLU:Aß42 involved in the reaction before addition to the cells. Thus, the effects of CLU on Aß42-induced cytotoxicity were likely determined by the extent to which it bound and sequestered toxic Aß42 oligomers or protofibrils. These findings suggest that CLU could influence amyloid neurotoxicity and pathogenesis by modulating Aß aggregation.

Vaspin protects vascular endothelial cells against free fatty acid-induced apoptosis through a phosphatidylinositol 3-kinase/Akt pathway.

Vaspin, an adipocytokine recently identified in a rat model of type 2 diabetes, has been suggested to have an insulin-sensitizing effect. However, the exact mechanism underlying this action has not been fully elucidated. Furthermore, the specific function of vaspin is largely unknown, especially in vascular cells. We examined whether vaspin affects the insulin-signaling pathway in cultured endothelial cells and is capable of preventing free fatty acid (FFA)-induced apoptosis in endothelial cells through its insulin sensitizing effect, specifically, through its stimulatory effect on PI3-kinase/Akt signaling pathways. Vaspin significantly increased Akt phosphorylation and prevented the impairment of Akt phosphorylation by linoleic acid (LA) in insulin-stimulated endothelial cells, which effects were abolished by pretreatment with the PI3-kinase inhibitor, Wortmannin. Moreover, pretreatment with vaspin prevented LA-induced apoptosis in insulin-stimulated endothelial cells; this anti-apoptotic effect of vaspin was also eliminated by pretreatment with Wortmannin. The present study indicates that vaspin protects vascular endothelial cells from FFA-induced apoptosis through upregulation of the PI3-kinase/Akt signaling pathway. Our study is the first to demonstrate that vascular cells can be targets of vaspin. Our results further suggest that vaspin could have beneficial effects on the atherosclerosis.

Peroxisome proliferator-activated receptor-gamma coactivator 1-alpha overexpression prevents endothelial apoptosis by increasing ATP/ADP translocase activity.

OBJECTIVE: Fatty acids increase reactive oxygen species generation and cell apoptosis in endothelial cells. The peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1alpha) is a transcriptional coactivator that increases mitochondrial biogenesis and fatty acid oxidation in various cells. This study was undertaken to investigate the possible preventive effect of PGC-1alpha on endothelial apoptosis and its molecular mechanism. METHODS AND RESULTS: Treatment with linoleic acid in cultured human aortic endothelial cells increased reactive oxygen species generation and cell apoptosis. These effects appeared to be mediated by increases in cytosolic fat metabolites, ie, fatty acyl CoA, diacylglycerol, and ceramide, and consequent decreases in ATP/ADP translocase activity of adenine nucleotide translocator. Adenoviral overexpression of PGC-1alpha prevented linoleic acid-induced increases in reactive oxygen species generation and cell apoptosis in human aortic endothelial cells by increasing fatty acid oxidation, decreasing diacylglycerol and ceramide, and increasing ATP/ADP translocase activity. In isolated aorta, PGC-1alpha overexpression prevented linoleic acid-induced decrease in endothelium-dependent vasorelaxation, and this effect was abolished by adenine nucleotide translocator1 shRNA. CONCLUSIONS: PGC-1alpha regulates reactive oxygen species generation and apoptosis in endothelial cells by increasing fatty acid oxidation and enhancing ATP/ADP translocase activity. Measures to increase PGC-1alpha expression or ATP/ADP translocase activity in vascular cells may aid in the prevention or treatment of atherosclerosis.

Evaluation of Student Satisfaction with Ubiquitous-Based Tests in Women's Health Nursing Course.

Learning evaluation using ubiquitous-based tests may be essential during a public health crisis, such as the COVID-19 pandemic, during which theoretical classes and clinical practice are conducted online. However, students may not be as familiar with ubiquitous-based tests as they are with paper-based tests. This survey study aimed to evaluate students' satisfaction with ubiquitous-based tests and compare the evaluation results of a paper-based test with that of a ubiquitous-based test in nursing education. For the midterm exam of the Women's Health Nursing course, a paper-based test was conducted, while a ubiquitous-based test using a tablet computer was used for the final exam. The Ubiquitous-Based Test Usefulness and Satisfaction tool, which has a five-point Likert-type response scale, was employed to evaluate the post-test usefulness and satisfaction scores of the ubiquitous-based test. The mean score of the ubiquitous-based test usefulness was 4.01 ± 0.67. There was a significant difference in satisfaction levels between the ubiquitous-based and the paper-based test (t = -3.36, p = 0.001). Specifically, the evaluation scores were not affected by different evaluation methods. Study participants deemed the ubiquitous-based test highly useful and satisfactory, suggesting that such tests may be a future-oriented evaluation method, potentially replacing paper-based tests.

Tablet PC-based competency evaluation for nursing students in three Asian countries: Cross-sectional comparative study.

AIM: This study evaluated a practical competency evaluation for nursing students in three Asian countries using tablet PC-based tests. The need to evaluate practical competencies in a non-face-to-face manner continues to pose challenges in nursing education. DESIGN: This study presents descriptive comparative research on a tablet PC-based evaluation of practical competencies in three countries. METHODS: tablet PC-based clinical practice competency evaluation was conducted among nursing college students in Korea, Vietnam and Mongolia. In total, 124 students answered 65 questions for practical competency evaluation and items on its usefulness. RESULTS: Students from Korea had the highest score of nursing competencies (41.6 points; n = 59, SD 6.02), followed by those from Vietnam (26.3 points; n = 30, SD 4.97) and Mongolia (18.4 points; n = 35, SD 5.36). Scores for usability showed an inverse relationship with competency scores. Questions incorporating video showed the lowest proportion of low-discrimination items. CONCLUSIONS: This research recognized that using video which provides contextual elements can increase item discrimination. These findings suggest that incorporating video into evaluation items in tablet-PC-based tests is useful for international comparison.

2020 Year of the nurse and the midwife: a call for strengthening midwifery in response to South Korea's ultra-low birth rate.

Along with the low birth rate in Korea, the aging of mothers is progressing very rapidly. Recent studies have reported that the obstetric infrastructure is crumbling due to the accelerating closures of obstetric medical institutions resulting from the low birth rate and low reimbursement rates for obstetric procedures. The number of birth centers has also decreased, but women's interest in natural birth has actually increased, such that deliveries at birth centers now account for 11.8% of deliveries in obstetric clinics. In the Netherlands, Japan, and the United Kingdom, initiatives to promote natural birth through care provided by midwives increased the rate of natural births, decreased the number of cesarean sections, and lowered the rate of postpartum complications. In light of these examples, South Korea should also encourage natural delivery by midwives. A national support system for midwife applicants is necessary, and the requirements for institutions that train midwives should be revised. Independent birth centers should have emergency prescription privileges, and women should be given the choice to have a natural delivery by creating birth centers within hospitals.

[Factors influencing infertility-related quality of life in infertile women]. / 난임 여성의 ë‚œìž„ê´€ë ¨ 삶의 질 영향요인.

Purpose: Infertile women experience various physical, psychological, and relational problems that affect their infertility-related quality of life (QoL). This study investigated infertile women's infertility-related QoL with the goal of identifying how it is influenced by fatigue, depression, and marital intimacy. Methods: A sample of 140 infertile women was surveyed in a cross-sectional study. Data were collected from February to April 2018 using self-report structured questionnaires at three infertility clinics located in Jeonju, Korea. Data were analyzed using the independent t-test, analysis of variance, Pearson correlation coefficients, and stepwise multiple regression analysis in SPSS for Windows version 25.0. The subjects agreed to complete a face-to-face interview, including administration of the Fatigue Severity Scale, Depression Anxiety Stress Scale-21, Marital Intimacy Scale, and the Fertility Quality of Life tool. Results: The mean age of the participants was 35.6±4.3 years. Infertility-related QoL was negatively correlated with fatigue (r=-.42, p<.001) and depression (r=-.56, p<.001), and positively correlated with marital intimacy (r=.30, p<.001). Multiple regression analysis showed that depression (ß=-0.44, p<.001), fatigue (ß=-0.27, p<.001), and husband's attitude (ß=-0.19, p=.007) had significant effects on the QoL of infertile women, accounting for 40.5% of the variance in infertility-related QoL. Conclusion: The study provides insights into how infertile women's infertility-related QoL was influenced by depression, fatigue, and their husbands' attitudes regarding infertility treatment. To improve infertile women's infertility-related QoL, healthcare providers should consider developing strategies to decrease depression and fatigue in infertile women and to address their husbands' attitudes.

Nurse staffing, quality of nursing care and nurse job outcomes in intensive care units.

AIM: To examine the relationship between nurse staffing and nurse-rated quality of nursing care and job outcomes. BACKGROUND: Nurse staffing has been reported to influence patient and nurse outcomes. DESIGN: A cross-sectional study with a survey conducted August-October 2007. METHODS: The survey included 1365 nurses from 65 intensive care units in 22 hospitals in Korea. Staffing was measured using two indicators: the number of patients per nurse measured at the unit level and perception of staffing adequacy at the nurse level. Quality of care and job dissatisfaction were measured with a four-point scale and burnout measured by the Maslach Burnout Inventory. Multilevel logistic regression models were used to determine the relationships between staffing and quality of care and job outcomes. RESULTS: The average patient-to-nurse ratio was 2.8 patients per nurse. A fifth of nurses perceived that there were enough nurses to provide quality care, one third were dissatisfied, half were highly burnt out and a quarter planned to leave in the next year. Nurses were more likely to rate quality of care as high when they cared for two or fewer patients (odds ratio, 3.26; 95% confidence interval, 1.14-9.31) or 2.0-2.5 patients (odds ratio, 2.44; 95% confidence interval, 1.32-4.52), compared with having more than three patients. Perceived adequate staffing was related to a threefold increase (odds ratio, 2.97; 95% confidence interval, 2.22-3.97) in the odds of nurses' rating high quality and decreases in the odds of dissatisfaction (odds ratio, 0.30; 95% confidence interval, 0.23-0.40), burnout (odds ratio, 0.50; 95% confidence interval, 0.34-0.73) and plan to leave (odds ratio, 0.40; 95% confidence interval, 0.28-0.56). CONCLUSIONS: Nurse staffing was associated with quality of care and job outcomes in the context of Korean intensive care units. RELEVANCE TO CLINICAL PRACTICE: Adequate staffing must be assured to achieve better quality of care and job outcomes.

Black soldier fly (Hermetia illucens) larvae enhances immune activities and increases survivability of broiler chicks against experimental infection of Salmonella Gallinarum.

Black soldier fly (Hermetia illucens) larvae (BSFL) are rich in protein and have the potential to be used in animal feed. The aim of the present study was to determine the immunoprophylactic effect of BSFL against Salmonella Gallinarum in broiler chicks as an alternative feed additive. Results showed that BSFL improved body weight gain and increased frequency of CD4+ T lymphocyte, serum lysozyme activity, and spleen lymphocyte proliferation. Moreover, BSFL reinforced bacterial clearance and increased survivability of broiler chicks against S. Gallinarum. These data suggested that BSFL has prophylactic properties with stimulating non-specific immune responses, as well as reduced bacterial burden against S. Gallinarum.

Nasal delivery of chitosan/alginate nanoparticle encapsulated bee (Apis mellifera) venom promotes antibody production and viral clearance during porcine reproductive and respiratory syndrome virus infection by modulating T cell related responses.

In this study, we administered specially developed chitosan/alginate nanoparticle encapsulated BV (CH/AL-BV) which has slow-releasing properties and mucosal adhesiveness to pig via nasal route and evaluate whether it can facilitate systemic immune response and improve clearance of porcine reproductive and respiratory syndrome virus (PRRSV). The CH/AL-BV-administered group with PRRSV vaccination showed significantly enhanced Th1-related responses including a high population of CD4+ T lymphocyte and cytokine mRNA levels including interferon-gamma (IFN-γ) and interleukin (IL)-12 and increased PRRSV-specific IgG levels. In the PRRSV challenge experiment, the CH/AL-BV group showed a significant decrease of viral burden in the sera and tissues (lung and bronchial lymph node) and mild interstitial pneumonia signs on both lung gross examination and microscopic evaluation with high levels of PRRSV-specific IgG and viral neutralizing antibody. CH/AL-BV also effectively induced not only Th1-related immune responses including increase in portion of CD4+ T lymphocyte, cytokines (IFN-γ and IL-12), and transcriptional factors (STAT4 and T-bet), but also stimulated IFN-γ-secreting cell families such as CD4+ T lymphocytes and Th/memory cells. Interestingly, the CH/AL-BV group showed decrease in PRRSV-specific immune-suppressive actions, including the T regulatory cell population and its related cytokines (IL-10 and TGF-ß) and transcriptional factors (STAT5 and Foxp3). Therefore, nasal-delivered CH/AL-BV may effectively induce non-specific immune stimulating actions, particularly those related to Th1 responses and viral clearance activities against PRRSV infection. Based on these results, CH/AL-BV could be a promising strategy for overcoming the disadvantages of classical PRRSV vaccination and can be applied as a preventive agent against PRRSV and other viral diseases, particularly those with immune-suppressive characteristics.

Effects of recombinant adenovirus-mediated uncoupling protein 2 overexpression on endothelial function and apoptosis.

Increased oxidative stress in vascular cells plays a key role in the development of endothelial dysfunction and atherosclerosis. Uncoupling protein 2 (UCP2) is an important regulator of intracellular reactive oxygen species (ROS) production. This study was undertaken to test the hypothesis that, UCP2 functions as an inhibitor of the atherosclerotic process in endothelial cells. Adenovirus-mediated UCP2 (Ad-UCP2) overexpression led to a significant increase in endothelial nitric oxide synthase (eNOS) and decrease in endothelin-1 mRNA expression in human aortic endothelial cells (HAECs). Moreover, UCP2 inhibited the increase in ROS production and NF-kappaB activation, and apoptosis of HAECs induced by lysophophatidylcholine (LPC) and linoleic acid. LPC and linoleic acid caused mitochondrial calcium accumulation and transient mitochondrial membrane hyperpolarization, which was followed by depolarization. UCP2 overexpression prevented these processes. In isolated rat aorta, Ad-UCP2 infection markedly improved impaired vascular relaxation induced by LPC. The data collectively suggest that UCP2, functions as a physiologic regulator of ROS generation in endothelial cells. Thus, measures to increase UCP2 expression in vascular endothelial cells may aid in preventing the development and progression of atherosclerosis in patients with metabolic syndrome.

Structure-antimicrobial activity relationship for silanols, a new class of disinfectants, compared with alcohols and phenols.

Triorganosilanols (R(CH(3))(2)SiOH) were recently reported to exhibit unexpectedly strong disinfectant properties. The antimicrobial activities of silanols were significantly higher than their analogous alcohols. A study of the structural dependence of their antimicrobial activity was conducted against four bacteria, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis. Silanols, alcohols with structures analogous to the silanols (R(CH(3))(2)COH) and substituted phenols were evaluated as a single class of materials. The minimum lethal concentrations (MLCs), defined as the concentration required for a 7-log reduction in viable bacteria after 1h exposure, were used to measure antimicrobial activity. Octanol-water partition coefficients (logP) and hydrogen bond acidities (deltanu), measured as the shift in frequency of the OH stretching band between free OH and hydrogen-bonded OH to diethyl ether oxygen by infrared spectroscopy, were utilised as dispersive and polar structural parameters, respectively. The correlation established by multiple regression analysis between antimicrobial activities and structural properties of silanols, alcohols and phenols against the four bacteria treated as a single family produced the following equation, log(1/MLC)=0.679 logP+0.0036deltanu-1.909 (n=282, r=0.96, s=0.22). This equation and the significantly high correlation coefficient supported the hypothesis that the lipophilic properties and the H-bond acidities are primary factors for the antimicrobial action of silanols, alcohols and phenols. The high antimicrobial activity of silanols is explained by their greater H-bond acidity and their enhanced lipophilicity.

Alpha-lipoic acid prevents endothelial dysfunction in obese rats via activation of AMP-activated protein kinase.

OBJECTIVE: Lipid accumulation in vascular endothelial cells may play an important role in the pathogenesis of atherosclerosis in obese subjects. We showed previously that alpha-lipoic acid (ALA) activates AMP-activated protein kinase (AMPK) and reduces lipid accumulation in skeletal muscle of obese rats. Here, we investigated whether ALA improves endothelial dysfunction in obese rats by activating AMPK in endothelial cells. METHODS AND RESULTS: Endothelium-dependent vascular relaxation was impaired, and the number of apoptotic endothelial cells was higher in the aorta of obese rats compared with control rats. In addition, triglyceride and lipid peroxide levels were higher, and NO synthesis was lower. Administration of ALA improved all of these abnormalities. AMPK activity was lower in aortic endothelium of obese rats, and ALA normalized it. Incubation of human aortic endothelial cells with ALA activated AMPK and protected cells from linoleic acid-induced apoptosis. Dominant-negative AMPK inhibited the antiapoptotic effects of ALA. CONCLUSIONS: Reduced AMPK activation may play an important role in the genesis of endothelial dysfunction in obese rats. ALA improves vascular dysfunction by normalizing lipid metabolism and activating AMPK in endothelial cells.