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71.
72.
Hiromu Miyake Yong Chen Yuhki Koike Alison Hock Bo Li Carol Lee Augusto Zani Agostino Pierro 《Pediatric surgery international》2016,32(12):1153-1156
Purpose
Administration of hyperosmolar formula is regarded as a risk factor for the development of necrotizing enterocolitis (NEC). However, there are limited number of reports about the relationship between formula osmolality and NEC. The aim of this study is to evaluate the effects of formula concentration in an experimental model of NEC.Methods
We studied experimental NEC in C57BL/6 mice. NEC was induced by giving hypoxia, gavage administration of lipopolysaccharide and gavage formula feeding from postnatal day 5–9. We used two types of formula: (1) hyperosmolar formula (HF): 15 g Similac + 75 ml Esbilac (849 mOsm/kg); (2) diluted formula (DF): dilute hyperosmolar formula with an equal amount of water (325 mOsm/kg). Controls were fed by the mother. On postnatal day 9, the ileum was harvested and evaluated for severity of mucosal injury (hematoxylin/eosin staining) and inflammation (PCR for IL6 and TNFα mRNA expression).Results
The incidence of NEC was same in both HF and DF (80%). The intestinal inflammatory response was similar between HF and DF (IL6: p = 0.26, TNFα: p = 0.69).Conclusions
This study indicates the osmolality of enteral formula does not affect incidence of experimental NEC. This experimental study provides new insights into the relationship between formula feeding and NEC.73.
74.
Synaptic vesicle dynamics in the mossy fiber-CA3 presynaptic terminals of mouse hippocampus 总被引:2,自引:0,他引:2
The mossy fiber (MF)-CA3 synapse in the hippocampus is unique in the CNS because of its wide dynamic range of transmitter release during short- and long-term plasticity. The presynaptic mechanisms underlying the fidelity of transmission were investigated for the MF-CA3 synapses. The relative size of readily releasable pool (RRP) of vesicles was estimated by counting the number of docked vesicles at an active zone (AZ) on the transmission electron microscopy (TEM) image. The size of the releasable pool and the exo-endocytosis kinetics were directly measured from individual large MF boutons in hippocampal slices of transgenic mice that selectively express synaptopHluorin (SpH), a pH-sensitive GFP fused to the lumenal aspect of one of the vesicular membrane proteins, VAMP-2, in these boutons. Here we found (1) there are distinct two vesicle pools, the resting pool which is resistant to exocytosis, and the releasable pool, (2) the initially docked vesicles are easily depleted and the RRP is maintained by refilling from the reserve subpopulation of releasable pool ("reserve" releasable pool), and (3) the contribution of rapid reuse of recycled vesicles is relatively small. Therefore, the fidelity of transmission is suggested to be ensured by the rapid refilling rate of RRP. 相似文献
75.
Imagawa E Matsuda K Hidaka E Uhara M Uehara T Sano K Yamauchi K 《Rinsho byori. The Japanese journal of clinical pathology》2007,55(12):1084-1087
Myeloid sarcoma (MS) is a tumor mass of myeloblasts or immature myeloid cells occurring in an extramedullary site or in bone. The tumor mass may precede or occur concurrently with acute or chronic myeloid leukemia or with other types of myeloproliferative disorders or myelodysplastic syndromes. MS is a rare disease, estimated to comprise between 2 to approximately 14% of acute myeloid leukemia. On the other hand, 95% of cases of CML have characteristic t (9;22) cytogenetic abnormality and BCR/ABL fusion gene at diagnosis. We here report the clinical significance of FISH in a diagnosis of MS that formed tumor in femur during the chronic phase of CML. 相似文献
76.
77.
Shiori Otsuki Eiko Saito Norie Sawada Sarah K. Abe Akihisa Hidaka Taiki Yamaji Taichi Shimazu Atsushi Goto Motoki Iwasaki Hiroyasu Iso Tetsuya Mizoue Kenji Shibuya Manami Inoue Shoichiro Tsugane 《Annals of epidemiology》2018,28(9):597-604.e6
Purpose
We investigated the association between reproductive history and mortality from all and major causes among Japanese women.Methods
A large-scale population-based cohort study in Japan included 40,149 eligible women aged 40–69 years in 1990–1994. A total of 4788 deaths were reported during follow-up (average 20.9 years). A Cox proportional hazards regression model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CI) for all-cause and major causes of mortality, adjusting for potential confounders.Results
Inverse associations with all-cause mortality were found in parous women (0.74 [0.67–0.82]), women with two or three births compared with a single birth (2 births: 0.88 [0.78–0.99]; 3 births: 0.83 [0.74–0.94]), parous women who breastfed (0.81 [0.75–0.87]), women who were older at menopause (0.88 [0.80–0.97]; p-trend: <0.01), and women who had a longer fertility span (0.85 [0.76–0.95]; p-trend: <0.01). A positive association was seen between all-cause mortality and later age at first birth (≥30 years) than early childbearing (≤22 years).Conclusions
Our study suggests that parous, two or three births, breastfeeding, late age at menopause, and longer reproductive span are associated with lower risk of all-cause of mortality. 相似文献78.
OBJECTIVE: We studied the effects of food components on the in vitro formation of calcium phosphate precipitates. MATERIALS AND METHODS: The effects of food components, such as starch, soybean flour, fish meal, rapeseed oil, and coconut oil, on calcium phosphate precipitation were studied using a pH drop method. RESULTS: Although the addition of starch had no effect on the rate of precipitation of amorphous calcium phosphate (ACP), it increased both the rate of transformation of ACP to hydroxyapatite (HAP) and the induction time (i.e. time for the initiation of transformation of ACP to HAP to occur); this was irrespective of the heat treatment of the starch. Amylopectin (insoluble constituent of starch) was effective in increasing the rate of HAP transformation, but amylose (soluble constituent of starch) was not. Oil specimen obtained from rapeseed (400 microl ml(-1)) increased the entire reaction of calcium phosphate precipitation, but that from coconut did not. Protein food, such as soybean flour and fish meal, decreased the rate of transformation of ACP to HAP and increased the induction time, while they had no effect on the rate of ACP precipitation. CONCLUSION: These results suggest that carbohydrate and oil (both are staple diets for the humans) enhance oral calcification (dental calculus formation or re-mineralization of tooth enamel), while side dishes of protein food would decrease it. 相似文献
79.
80.
Takuya Tomizawa Masahiro Ishikawa Sheila N. Bello-Irizarry Karen L. de Mesy Bentley Hiromu Ito Stephen L. Kates John L. Daiss Christopher Beck Shuichi Matsuda Edward M. Schwarz Kohei Nishitani 《Journal of orthopaedic research》2020,38(4):852-860
Despite its presence in orthopaedic infections, Staphylococcus epidermidis's ability to directly induce inflammation and bone destruction is unknown. Thus, we compared a clinical strain of methicillin-resistant biofilm-producing S. epidermidis (RP62A) to a highly virulent and osteolytic strain of methicillin-resistant Staphylococcus aureus (USA300) in an established murine implant-associated osteomyelitis model. Bacterial burden was assessed by colony forming units (CFUs), tissue damage was assessed by histology and micro-computed tomography, biofilm was assessed by scanning electron microscopy (SEM), host gene expression was assessed by quantitative polymerase chain reaction, and osseous integration was assessed via biomechanical push-out test. While CFUs were recovered from RP62A-contaminated implants and surrounding tissues after 14 days, the bacterial burden was significantly less than USA300-infected tibiae (p < 0.001). In addition, RP62A failed to produce any of the gross pathologies induced by USA300 (osteolysis, reactive bone formation, Staphylococcus abscess communities, marrow necrosis, and biofilm). However, fibrous tissue was present at the implant-host interface, and rigorous SEM confirmed the rare presence of cocci on RP62A-contaminated implants. Gene expression studies revealed that IL-1β, IL-6, RANKL, and TLR-2 mRNA levels in RP62A-infected bone were increased versus Sterile controls. Ex vivo push-out testing showed that RP62A-infected implants required significantly less force compared with the Sterile group (7.5 ± 3.4 vs. 17.3 ± 4.1 N; p < 0.001), but required 10-fold greater force than USA300-infected implants (0.7 ± 0.3 N; p < 0.001). Taken together, these findings demonstrate that S. epidermidis is a commensal pathogen whose mechanisms to inhibit osseous integration are limited to minimal biofilm formation on the implant, and low-grade inflammation. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:852-860, 2020 相似文献