Synthesis of novobiocin derivatives and evaluation of their antigonococcal activity and pharmacokinetics.

Gonorrhea has become a serious problem because the number of infected people is increasing and the multi-drug resistance of the causative bacteria, Neisseria gonorrhoeae, is progressing. To develop novel drugs against resistant N. gonorrhoeae, we focused on the antibiotic novobiocin (1). This natural product has a different mechanism of action from existing drugs for gonorrhea, which may make it effective against resistant strains. Actually, it was applied to resistant N. gonorrhoeae, and moderate antibacterial activity was confirmed. Based on this result, we investigated the development of an antigonococcal drug with 1 as the lead compound. The pharmacophore is thought to be the noviose sugar moiety, especially around the 3'-position, so we derivatized this part in order to improve antibacterial activity. As a result, we found that 5 with an methylpyrrole ester structure have a very potent antibacterial activity. This derivative also showed excellent antigonococcal activity against resistant strains in vitro, however it has poor water solubility and pharmacokinetics because it is the acidic lipid-soluble compound. Therefore, we considered introduction of a basic substituent into the molecule would result in an amphoteric compound with improved water solubility, and we investigated further derivatization. As a result of synthesizing various derivatives, we found 47 containing imidazole with strong antigonococcal activity and greatly improved water solubility. This derivative has also improved metabolism and blood concentration in vivo, and is expected to be orally absorbed. Based on these results, we believe that 47 is a very promising anti-gonococcal lead compound and has great potential for further development.

Prevalence of sarcopenia and its association with diet and physical activity in older adults with type 2 diabetes: A cross-sectional study.

This cross-sectional study explored the prevalence of sarcopenia in older adults with type 2 diabetes and investigated the effects of diet and physical activity on sarcopenia. In total, 577 older adults with diabetes were recruited from a teaching hospital in Taiwan. Diet and physical activity were assessed using self-rated questionnaires, including the Healthy Diet Inventory, the Mini Nutritional Assessment-Short Form, and the International Physical Activity Questionnaire-Short Form. Sarcopenia was defined in accordance with the Asian Working Group for Sarcopenia 2019 guidelines. In total, 51.12% of participants had either possible sarcopenia, sarcopenia, or severe sarcopenia. Participants who were female, old age, prolonged sedentary times, poor nutritional status, and lower level of moderate-to-vigorous physical activity were identified as risk factors for possible to severe sarcopenia. Older adults with diabetes and possible to severe sarcopenia had poor nutrition status and engaged in inadequate physical activity. The findings indicate that sarcopenia may be related to nutrition status and physical activity, especially in older adults with diabetes.

A mammary fibroadenoma with terminal end buds-like structures in a 7-week-old male SD rat.

We report a case of mammary fibroadenoma in a 7-week-old male SD rat. This case showed rapid growth within one week from the time when the nodule was detected. Histologically, the nodule was a well-circumscribed subcutaneous mass. The tumor consisted of an epithelial component with island-like proliferation (cribriform to tubular patterns) and an abundant mesenchymal component. Alpha-SMA-positive cells were arranged at the periphery of the epithelial component and showed cribriform and tubular patterns. Discontinuous basement membranes and high cell proliferative activities were observed in the cribriform area. These features resembled those of normal terminal end buds (TEBs). Since the mesenchymal component had abundant fine fibers and a mucinous matrix, its stroma was regarded as neoplastic growth of fibroblasts; thus, this tumor was diagnosed as a fibroadenoma. This case is an extremely rare fibroadenoma in that it occurred in a young male SD rat and was composed of an epithelial component showing multifocal proliferation of TEB-like structures and a mucinous mesenchymal component consisting of fibroblasts with fine collagen fibers.

The Plasma Proteome Fingerprint Associated with Circulating Carotenoids and Retinol in Older Adults.

BACKGROUND: Although diets rich in carotenoids are associated with reduced risks of cardiovascular disease, age-related macular degeneration, disability, and other adverse aging outcomes, the underlying biological mechanisms are not fully elucidated. OBJECTIVES: To characterize the plasma proteome fingerprint associated with circulating carotenoid and retinol concentrations in older adults. METHODS: In 728 adults ≥65 y participating in the Invecchiare in Chianti (InCHIANTI) Study, plasma α-carotene, ß-carotene, ß-cryptoxanthin, lutein, zeaxanthin, and lycopene were measured using HPLC. The SOMAscan assay was used to measure 1301 plasma proteins. Multivariable linear regression models were used to examine the relationship of individual carotenoids and retinol with plasma proteins. A false discovery rate approach was used to deal with multiple comparisons using a q-value < 0.05. RESULTS: Plasma ß-carotene, ß-cryptoxanthin, lutein, zeaxanthin, and lycopene were associated with 85, 39, 4, 2, and 5 plasma proteins, respectively, in multivariable linear regression models adjusting for potential confounders (q < 0.05). No proteins were associated with α-carotene or retinol. Two or more carotenoids were positively associated with ferritin, 6-phosphogluconate dehydrogenase (decarboxylating), hepcidin, thrombospondin-2, and choline/ethanolamine kinase. The proteins associated with circulating carotenoids were related to energy metabolism, sirtuin signaling, inflammation and oxidative stress, iron metabolism, proteostasis, innate immunity, and longevity. CONCLUSIONS: The plasma proteomic fingerprint associated with elevated circulating carotenoids in older adults provides insight into the mechanisms underlying the protective role of carotenoids on health.

Factors affecting the quality of dementia care at acute care hospitals: A cross-sectional study.

AIM AND OBJECTIVES: The purpose of this study was to investigate which factors are associated with the quality of dementia care in acute care hospitals. BACKGROUND: The number of people with dementia who are admitted to acute care hospitals is increasing. Improving the quality of dementia care in acute care hospitals is an important issue. Prior studies have demonstrated that not only knowledge and nursing experience, but also psychological factors and the nursing practice environment are related to high-quality care on general wards. DESIGN: Cross-sectional hypothesis-testing design. METHODS: Participants were nurses providing care to people with dementia at acute care hospitals. Questionnaires were distributed to 300 acute care hospitals in Japan, 10 copies each and 773 valid responses were received. Based on the hypothesis model, variables were tested using multiple regression analysis. The model described the relationship between quality of care, personal attributes and the nursing practice environment. The Strengthening the Reporting of Observational Studies in Epidemiology checklist was used. RESULTS: Almost 90% of the study sample was female, the mean age was 37.4 ± 9.3 years, and the mean nursing experience was 14.0 ± 8.7 years. The results showed that nursing foundations for quality of care, staffing and resource adequacy, specialist consultation, promoting systematic recreation and exchange, knowledge, and feelings towards people with dementia were associated with the quality of dementia care in acute care hospitals. The adjusted coefficient of determination was 0.367. CONCLUSION: This study identified factors associated with the quality of dementia care in acute care hospitals. Knowledge and feelings towards people with dementia are important, and the nursing practice environment plays an important role in improving the quality of dementia care. RELEVANCE TO CLINICAL PRACTICE: Not only improving nurse's practical ability but also a supportive nursing practice environment enhances the quality of dementia care in acute care hospitals.

Effects of a virtual reality intervention on dementia care education among acute care nurses in Japan: A non-randomised controlled trial.

This study aimed to evaluate the effects of a virtual reality intervention for dementia care education in Japanese acute care nurses. Non-randomised controlled trial was used to assess the effectiveness of the intervention pre- and post-intervention and at a 1-month follow-up. This study enrolled 20 and 19 nurses in the intervention and control groups, respectively. Generalized estimating equation analyses revealed significant differences in scores on the Dementia Nursing Competency Scale in Acute Hospitals and Staff Experiences of Working with Dementia Residents questionnaire in the intervention group. A post hoc test revealed significantly higher scores on the Dementia Nursing Competency Scale in Acute Hospitals at 1 month after compared with pre-intervention. Staff Experiences of Working with Dementia Residents questionnaire scores were significantly lower at pre- than that at post-intervention and 1 month after intervention. These findings could improve competency of dementia nursing care and attitudes toward people with dementia.

Malignant pinealoma observed in the deep cerebral parenchyma of a male Wistar rat.

This report describes a case of spontaneous malignant pinealoma in a 90-week-old male Wistar rat. The tumor mass occurred in the deep cerebral parenchyma and no intact pineal gland was observed in the area between the posterior-dorsal median line of the cerebrum and the cerebellum. The tumor was characterized by a large nodular proliferation occupying the central area of the brain, extending from the dorsal surface to the base of the brain, corresponding to the thalamus. The tumor cells had round to irregular oblong nuclei approximately 5-17 µm in diameter and showed faintly or moderately eosinophilic cytoplasm and indistinct cell boundaries. Immunohistochemically, the tumor cells were positive for synaptophysin and partially positive for neuron-specific enolase (NSE). The tumor showed malignant features including cellular pleomorphism, high mitotic index, necrotic foci, and invasive and extensive growth and was, therefore, diagnosed as an extremely rare malignant pinealoma in the deep cerebral parenchyma.

A possible critical dosing period of p-cumylphenol for development of cystic kidneys in rat neonates.

In accordance with a previous report on cystic kidneys induced in rat neonates when dosed with p-cumylphenol (PCP) for 18 days from postnatal day (PND) 4, 3 rat neonates were dosed with PCP once a day for 14 days, either from PND 14, 21, 28, 35, or 42 as W2, W3, W4, W5, and W6 groups, respectively, to investigate whether dosing periods in different PNDs influenced the development of cystic renal tubules. The lesion was striking in the W2 group and at a lesser magnitude in the W3 group, whereas either kidney was unaffected when dosing was initiated beyond PND 28. These findings, together with the results from the previous study, suggested that PND 14-28 is a critical dosing period for PCP to develop cystic kidneys in rat neonates. The lining epithelium of the cystic tubules was immunohistochemically positive for AQP2. This finding and the anatomical location indicated that the cystic tubules were of collecting duct origin. Either obstruction, fluid accumulation, or reparative hyperplasia of the lining epithelium was unlikely to be involved in the formation of cystic tubules lined with a monolayer of cuboidal or columnar epithelium with a high nuclear density. Thus, the follow-up investigation on PCP suggested a critical dosing period of PND 14-28 in rat neonates for the development of cystic dilation of renal collecting ducts. This study further supports that additive hyperplasia of the lining epithelium is a fundamental basis of this unique lesion.

Factors associated with the well-being of family caregivers of people with dementia.

BACKGROUND: Improving the health and well-being of family caregivers of people with dementia has become an increasingly important public health and policy issue in China. The aims of this study were to clarify the factors associated with the well-being of family caregivers of people with dementia in China. METHODS: Data were collected from a sample of 132 family caregivers who volunteered to study and live together with people with dementia who had been treated as outpatients in three hospitals in China. The survey included questions on the family caregivers' characteristics, satisfaction with family support, positive aspects of caregiving, preparedness of caregiving, and characteristics of people with dementia. Multiple linear regression analysis was carried out to identify factors associated with the well-being of family caregivers. RESULTS: The mean age of the family caregivers (68.2% women) was 46.8 ± 14.9 years. The results of multiple linear regression analysis indicated that positive aspects of caregiving (ß = 0.352, P < 0.001), satisfaction with family support (ß = 0.219, P < 0.01), activities of daily living of people with dementia (ß = 0.265, P < 0.05), and household size (ß = -0.184, P < 0.05) were related to the well-being of family caregivers. CONCLUSIONS: The findings from this study indicated that positive aspects of caregiving, satisfaction with family support, activities of daily living of people with dementia, and household size were significant factors related to the well-being of family caregivers. These findings could be expected to aid healthcare providers in identifying the optimal solution to enhance the well-being of family caregivers in China.

Spontaneous well-differentiated pancreatic islet cell carcinoma with vascular invasion in a male F344 rat.

This case report describes a case of spontaneous pancreatic islet cell carcinoma with vascular invasion in a 110-week-old male F344 rat. Histologically, a pancreatic nodule consisting of tumor cells and many blood-rich vessels, and covered with a fibrous capsule showed local invasion in the capsule and adjacent acinar tissues, encircling a large duct-like structure (DS). The tumor was composed of well-differentiated tumor cells resembling normal pancreatic islet cells, which had small round nuclei and eosinophilic cytoplasm. Mitotic figures were rare. Immunohistochemistry revealed that the tumor cells were positive for insulin. Although endothelial cells were not detected, the DS wall showed cells positive for α-smooth muscle actin and elastic fibers, suggesting that the DS is the pancreatic artery. This is a rare case of islet cell carcinoma consisting of well-differentiated tumor cells with invasion of the pancreatic artery in a rat.

Changes in 5-Fluorouracil-induced external granular cell damage during the time-course of the developing cerebellum of infant rats.

5-Fluorouracil (5-FU) is widely used as a chemotherapeutic agent that blocks DNA synthesis and replication by inhibiting thymidylate synthetase. This study aimed to elucidate 5-FU-induced changes in the external granular cells (EGCs) in the cerebellum of infant rats and the possible underlying mechanism. Six-day-old infant rats were injected subcutaneously with 40 mg/kg of 5-FU, and their cerebellums were examined at 6, 9, 12, and 24 h after treatment (HAT), and 2, 4, and 10 d after treatment (DAT). The width of the external granular layer (EGL) decreased from 24 HAT to 4 DAT in the 5-FU group compared to that in the control group. However, the width in the 5-FU group was comparable to that of the control group at 10 DAT. The number of apoptotic cells, cleaved caspase 3-labeling index (LI%), p21cip1-LI%, and expression levels of p53, p21cip1, and Fas mRNAs increased at 24 HAT. However, no changes were detected in the expression levels of Puma and Bax mRNAs at any time point. BrdU-LI% increased at 6 and 12 HAT but decreased at 24 HAT. The phospho-histone H3-LI% decreased from 6 HAT to 2 DAT. The width of the molecular layer decreased compared to that of the control group at 10 DAT. No differences were observed in Purkinje cell development. These results indicate that 5-FU inhibited cell proliferation by inducing apoptosis of EGCs via activation of Fas and caspase-3 without the involvement of the mitochondrial pathway and induced p53-dependent G1-S and G2-M phase arrest.

Porencephaly with an optic organ abnormality in a beagle dog.

A female TOYO beagle dog showed porencephaly and visual organ abnormalities. At necropsy, there was a cavity filled with cerebrospinal fluid in the right cerebral hemisphere and an adhesion area between the cerebral cortex and the skull, which was partially thickened. Additionally, the right optic nerve showed a slight decrease in diameter. Histopathological examination revealed increased glial fibers and collagen fibers, hemosiderin deposition, and an increased number of microglia in the adhesion area, along with a marked reduction of the cerebral parenchyma. In the right eyeball, the retina and optic nerve showed focal atrophy in the nerve fiber layer and inner granular layer to full retinal atrophy and hypoplasia of the myelinated nerve fibers, respectively. Electron microscopic examination revealed hypoplasia of the myelin sheath of nerve fibers in the right optic nerve. This is an extremely rare case of porencephaly and congenital optic nerve hypoplasia, along with independent retinal thinning.

Lifestyle factors associated with muscle quality in community-dwelling older people with type 2 diabetes in Japan and Taiwan: a cross-sectional study.

BACKGROUND: Type 2 diabetes mellitus (T2DM), common in older people, is an important reason for muscle loss in Japanese and Taiwanese populations. However, little is known about the association between lifestyle behaviours and muscle quality. We aimed to compare the lifestyle behaviours of Japanese and Taiwanese older adults with T2DM and to the identify lifestyle factors associated with muscle quality. METHODS: This cross-sectional study was conducted among community-dwelling individuals with T2DM aged ≥65 years in Taiwan and Japan. Totally, 114 Japanese and 226 Taiwanese participants were enrolled in the study. Outcomes were measured by blood biochemical examinations, body composition analyses and structured self-reported questionnaires to assess lifestyle behaviours and muscle quality. Linear regression models were used to examine the relationship between lifestyle factors and muscle quality using SPSS version 27.0 with a statistical significance level of P < 0.05. RESULTS: Japanese subjects were more likely to be smokers and alcohol consumers, and they were less likely to have well-balanced diets and engage in more physical activity as compared to Taiwanese subjects. The muscle quality in the Japanese subjects was significantly poorer than that in the Taiwanese subjects. Physical activity, dietary habits and smoking were associated with muscle quality, after adjusting for age, gender and body mass index. CONCLUSIONS: Physical activity of insufficient intensity, unhealthy dietary habits and smoking could be risk factors for poor muscle quality. These findings can contribute to the development of effective strategies to improve muscle quality in community-dwelling older Asian people with T2DM.

Plasma metabolites associated with chronic kidney disease and renal function in adults from the Baltimore Longitudinal Study of Aging.

INTRODUCTION: Chronic kidney disease (CKD) is an important cause of disability and death, but its pathogenesis is poorly understood. Plasma metabolites can provide insights into underlying processes associated with CKD. OBJECTIVES: To clarify the relationship of plasma metabolites with CKD and renal function in human. METHODS: We used a targeted metabolomics approach to characterize the relationship of 450 plasma metabolites with CKD and estimated glomerular filtration rate (eGFR) in 616 adults, aged 38-94 years, who participated in the Baltimore Longitudinal Study of Aging. RESULTS: There were 74 (12.0%) adults with CKD. Carnitine, acetylcarnitine, propionylcarnitine, butyrylcarnitine, trigonelline, trimethylamine N-oxide (TMAO), 1-methylhistidine, citrulline, homoarginine, homocysteine, sarcosine, symmetric dimethylarginine, aspartate, phenylalanine, taurodeoxycholic acid, 3-indolepropionic acid, phosphatidylcholines (PC).aa.C40:2, PC.aa.C40:3, PC.ae.C40:6, triglycerides (TG) 20:4/36:3, TG 20:4/36:4, and choline were associated with higher odds of CKD in multivariable analyses adjusting for potential confounders and using a false discovery rate (FDR) to address multiple testing. Six acylcarnitines, trigonelline, TMAO, 18 amino acids and biogenic amines, taurodeoxycholic acid, hexoses, cholesteryl esters 22:6, dehydroepiandrosterone sulfate, 3-indolepropionic acid, 2 PCs, 17 TGs, and choline were negatively associated with eGFR, and hippuric acid was positively associated with eGFR in multivariable analyses adjusting for potential confounders and using a FDR approach. CONCLUSION: The metabolites associated with CKD and reduced eGFR suggest that several pathways, such as the urea cycle, the arginine-nitric oxide pathway, the polyamine pathway, and short chain acylcarnitine metabolism are altered in adults with CKD and impaired renal function.

Effect of Employment Status on the Association Among Sleep, Care Burden, and Negative Affect in Family Caregivers.

OBJECTIVE: To examine the effect of employment status on sleep, care burden, and negative affect among family caregivers (FCs) at home. METHODS: An intensive longitudinal design was applied in which 25 FCs underwent in-home assessments for up to 56 days. At baseline, demographic data and employment status were collected. FCs wore a wrist-worn device with an accelerometer to assess objective total sleep time (TST) for consecutive 24-hour periods. FCs answered the Zarit Burden Interview (ZBI) and Positive and Negative Affect Schedule (PANAS) every night before sleep. Linear mixed model analysis was used to examine the effect of objective sleep status on ZBI and PANAS scores the following day. RESULTS: Mean participant age was 66.3 ± 10.8 years (72.0% female), and mean survey period was 29.1 ± 9.6 days (866 observations). Mean TST of FCs was 5.7 ± 1.4 hours. In total, 32.0% of FCs were employed either full- or part-time. TST of employed FCs was significantly associated with care burden and negative affect (B = -0.4 and -1.3, respectively); however, positive affect was not associated with TST. FCs who were unemployed experienced less care burden and negative affect (rate of change: -7.7 and -8.0, respectively). Additionally, TST of unemployed FCs was associated with negative affect; thus, when they slept 1 hour longer than their mean TST, they experienced less negative affect the following day. CONCLUSION: A reduction in TST could lead to increased care burden and more severe negative affect the following day, which may be moderated by employment status.

Anterior segment dysmorphogenesis of the eye and glaucoma in MG-W gerbils.

Unilaterally swollen eyes were histopathologically characterized in four MG-W gerbils. The primary lesions resided in the anterior segment of the eye where neural crest cells play a critical role in embryonic development. They included indistinct filtration angle, unformed canal of Schlemm, hypoplastic iris, and ciliary body. The findings noted in the retina, optic nerve, optic tract, and lateral geniculate nucleus were consistent with the lesions induced following the persistent elevation of intraocular pressure as a result of insufficient drainage of aqueous humor. Thus, the present cases observed in the eyes of MG-W gerbils exemplified the anterior segment dysmorphogenesis associated with inadequate neural crest migration or differentiation, leading to subsequent glaucoma.

Time-course changes in 5-fluorouracil-induced neural progenitor cell damages in the developing rat brain.

5-Fluorouracil (5-Fu) is a DNA-damaging agent and teratogenic in rodents. This study aimed to investigate its influence on neural progenitor cells (NPCs) in the developing fetal rat brain. Dams were intraperitoneally injected with 5-Fu (50 mg/kg b.w.) on gestation day 13 and its effects on fetal NPCs were observed from 3 to 72 hours after treatment (HAT), via periodic examination at six intervals. In NPCs of the fetal brain, the p53-labeling index (LI%) was markedly elevated at 3 HAT. Pyknosis and cleaved caspase-3-LI% also increased at 3 HAT, reaching peak values at 9 and 12 HAT. These parallel changes suggested the induction of apoptosis through a p53-mediated pathway. Pyknotic NPCs were distributed across the ventricular zone (VZ) of the telencephalic wall until 12 HAT, and became localized in the medial and dorsal layers at 12 and 48 HAT. Significant decreases in the numbers of mitotic NPCs and BrdU-LI% were noted from 3 HAT and 24 HAT, respectively. BrdU-positive NPCs were located in the ventral and middle layer at 24 and 48 HAT. p21-positive cells were detected at 12 and 24 HAT. The present results demonstrated that p53-mediated apoptosis was induced in all phases of the cell cycle of the NPCs in the early stage after 5-FU treatment. Furthermore, apoptosis of NPCs and suppression of cell proliferative activity are the events that take place in parallel leading to prominent reduction in the width of the telencephalic wall.

Pathological study of tubular aggregates occurring spontaneously in the skeletal muscles of non-obese diabetic/Cg-PrkdcscidIl2rgtm1sug /ShiJic (NOG) mice.

To examine the biological and morphological features of tubular aggregates (TAs) in the skeletal muscles of non-obese diabetic/Cg-PrkdcscidIl2rgtm1Sug /ShiJic (NOG) mice, 73 male and 72 female specific-pathogen-free NOG mice were examined at 7, 18, 22, 26, and 52 weeks of age. TAs were observed as intracytoplasmic eosinophilic materials of the femoral muscles in males at 18, 22, 26, and 52 weeks of age and in females at 52 weeks of age; gender-related differences were noted in the onset time and lesion degree. Intracytoplasmic materials were positive for Gomori's trichrome stain. Electron microscopy revealed that TAs were composed of an accumulation of dilated sarcoplasmic reticulum. In addition, TAs were observed in the femoral and gastrocnemius muscles, but not in the soleus and diaphragm muscles, suggesting that TAs are present in fast muscle fibers. The morphology of TAs and the type of myofibers involved, as well as the gender difference in NOG mice were essentially the same as those of TAs observed in C57BL/6J and MRL+/+ mice.

Association between sleep, care burden, and related factors among family caregivers at home.

AIM: Several studies have reported a negative correlation between depressive symptoms and family caregivers' (FCs) subjective sleep status. However, there is a paucity of information on the association between objective/subjective sleep status, care burden, and related factors. METHODS: Participants were 23 pairs of care receivers (CRs; Mage = 82.7 ± 8.5 years; 69.6% women) receiving long-term care at home and their FCs (Mage = 66.9 ± 11.0 years; 69.6% women). At baseline, demographic data, subjective sleep status (Pittsburgh Sleep Quality Index; PSQI), WHO-5 well-being, depressive mood, and frequency of going outdoors were collected. FCs wore a small, wrist-worn device with an accelerometer to assess objective sleep status for a consecutive 24-h 2-week period, and they answered the Zarit Burden Interview short version (ZBI) every night before sleep. After 3 months, CR status was collected and analysed retrospectively. RESULTS: The mean total sleep time over 2 weeks was 349.5 ± 69.6 min. The mean ZBI score over 2 weeks was 8.8 ± 6.8, which was significantly correlated with total sleep time (r = -0.42; P < 0.05), total time in bed (r = -0.44; P < 0.05), PSQI (r = 0.62; P < 0.01), frequency of going outdoors by CRs (r = -0.42; P < 0.05), and WHO-5 well-being among CRs (r = -0.50; P < 0.05). Multiple regression analyses revealed that total sleep time (ß = -0.51; P < 0.05) was significantly associated with care burden (adjusted R2 = 0.45). At the 3-month follow-up, four CRs had been hospitalised or died, and their FCs displayed significantly severe care burden and slept less than at baseline. CONCLUSIONS: Reduced objective total sleep time is significantly associated with the severity of care burden among FCs. Home-based care is critical in Japan; therefore, it is meaningful to determine how to reduce care burden.

Natural mutations in a Staphylococcus aureus virulence regulator attenuate cytotoxicity but permit bacteremia and abscess formation.

Staphylococcus aureus is a major bacterial pathogen, which causes severe blood and tissue infections that frequently emerge by autoinfection with asymptomatically carried nose and skin populations. However, recent studies report that bloodstream isolates differ systematically from those found in the nose and skin, exhibiting reduced toxicity toward leukocytes. In two patients, an attenuated toxicity bloodstream infection evolved from an asymptomatically carried high-toxicity nasal strain by loss-of-function mutations in the gene encoding the transcription factor repressor of surface proteins (rsp). Here, we report that rsp knockout mutants lead to global transcriptional and proteomic reprofiling, and they exhibit the greatest signal in a genome-wide screen for genes influencing S. aureus survival in human cells. This effect is likely to be mediated in part via SSR42, a long-noncoding RNA. We show that rsp controls SSR42 expression, is induced by hydrogen peroxide, and is required for normal cytotoxicity and hemolytic activity. Rsp inactivation in laboratory- and bacteremia-derived mutants attenuates toxin production, but up-regulates other immune subversion proteins and reduces lethality during experimental infection. Crucially, inactivation of rsp preserves bacterial dissemination, because it affects neither formation of deep abscesses in mice nor survival in human blood. Thus, we have identified a spontaneously evolving, attenuated-cytotoxicity, nonhemolytic S. aureus phenotype, controlled by a pleiotropic transcriptional regulator/noncoding RNA virulence regulatory system, capable of causing S. aureus bloodstream infections. Such a phenotype could promote deep infection with limited early clinical manifestations, raising concerns that bacterial evolution within the human body may contribute to severe infection.