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101.
102.
Erik Munson Tina Endes Katharine Vaughan Timothy Block Jeanne E. Hryciuk 《Mycopathologia》2009,167(4):191-195
We hereby report two instances of dimorphic fungus cultivation in BacT/ALERT®-based bacteriologic media, with the first such characterization of Blastomyces dermatitidis. From a patient with disseminated coccidioidomycosis, routine blood cultures incubated on the MB/BacT® 3D? Microbial Detection System generated a positive signal following 75 h of incubation. B. dermatitidis was isolated from a patient hospitalized with a four-week course of respiratory illness. Organism detection from respiratory specimens via the MB/BacT® 3D? Mycobacteria Detection System occurred 5 days sooner than the routine fungus culture. Etiologic agents of endemic mycoses may be isolated in bacteriologic media employed by continuous monitoring instrumentation. 相似文献
103.
Carmen Huesa Dean Houston Tina Kiffer-Moreira Manisha C. Yadav Jose Luis Millan Colin Farquharson 《Biochemistry and Biophysics Reports》2015
Phosphatases are recognized to have important functions in the initiation of skeletal mineralization. Tissue-nonspecific alkaline phosphatase (TNAP) and PHOSPHO1 are indispensable for bone and cartilage mineralization but their functional relationship in the mineralization process remains unclear. In this study, we have used osteoblast and ex-vivo metatarsal cultures to obtain biochemical evidence for co-operativity and cross-talk between PHOSPHO1 and TNAP in the initiation of mineralization. Clones 14 and 24 of the MC3T3-E1 cell line were used in the initial studies. Clone 14 cells expressed high levels of PHOSPHO1 and low levels of TNAP and in the presence of β-glycerol phosphate (βGP) or phosphocholine (P-Cho) as substrates and they mineralized their matrix strongly. In contrast clone 24 cells expressed high levels of TNAP and low levels of PHOSPHO1 and mineralized their matrix poorly. Lentiviral Phospho1 overexpression in clone 24 cells resulted in higher PHOSPHO1 and TNAP protein expression and increased levels of matrix mineralization. To uncouple the roles of PHOSPHO1 and TNAP in promoting matrix mineralization we used PHOSPHO1 (MLS-0263839) and TNAP (MLS-0038949) specific inhibitors, which individually reduced mineralization levels of Phospho1 overexpressing C24 cells, whereas the simultaneous addition of both inhibitors essentially abolished matrix mineralization (85%; P<0.001). Using metatarsals from E15 mice as a physiological ex vivo model of mineralization, the response to both TNAP and PHOSPHO1 inhibitors appeared to be substrate dependent. Nevertheless, in the presence of βGP, mineralization was reduced by the TNAP inhibitor alone and almost completely eliminated by the co-incubation of both inhibitors. These data suggest critical non-redundant roles for PHOSPHO1 and TNAP during the initiation of osteoblast and chondrocyte mineralization. 相似文献
104.
Kheng-Seang Lim Ai-Huey Tan Chun-Shen Lim Kek-Heng Chua Ping-Chin Lee Norlisah Ramli Giri Shan Rajahram Fatimah Tina Hussin Kum-Thong Wong Meenakshi B. Bhattacharjee Ching-Ching Ng 《PloS one》2015,10(8)
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary stroke caused by mutations in NOTCH3 gene. We report the first case of CADASIL in an indigenous Rungus (Kadazan-Dusun) family in Kudat, Sabah, Malaysia confirmed by a R54C (c.160C>T, p.Arg54Cys) mutation in the NOTCH3. This mutation was previously reported in a Caucasian and two Korean cases of CADASIL. We recruited two generations of the affected Rungus family (n = 9) and found a missense mutation (c.160C>T) in exon 2 of NOTCH3 in three siblings. Two of the three siblings had severe white matter abnormalities in their brain MRI (Scheltens score 33 and 50 respectively), one of whom had a young stroke at the age of 38. The remaining sibling, however, did not show any clinical features of CADASIL and had only minimal changes in her brain MRI (Scheltens score 17). This further emphasized the phenotype variability among family members with the same mutation in CADASIL. This is the first reported family with CADASIL in Rungus subtribe of Kadazan-Dusun ethnicity with a known mutation at exon 2 of NOTCH3. The penetrance of this mutation was not complete during the course of this study. 相似文献
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106.
Myeloid cells, which include monocytes, macrophages, and granulocytes, are important innate immune cells, but the mechanism and downstream effect of their cell death on the immune system is not completely clear. Necroptosis is an alternate form of cell death that can be triggered when death receptor-mediated apoptosis is blocked, for example, in stimulated Fas-associated Death Domain (FADD) deficient cells. We report here that mice deficient for FADD in myeloid cells (mFADD-/-) exhibit systemic inflammation with elevated inflammatory cytokines and increased levels of myeloid and B cell populations while their dendritic and T cell numbers are normal. These phenotypes were abolished when RIP3 deficiency was introduced, suggesting that systemic inflammation is caused by RIP3-dependent necroptotic and/or inflammatory activity. We further found that loss of MyD88 can rescue the systemic inflammation observed in these mice. These phenotypes are surprisingly similar to that of dendritic cell (DC)-specific FADD deficient mice with the exception that DC numbers are normal in mFADD-/- mice. Together these data support the notion that innate immune cells are constantly being stimulated through the MyD88-dependent pathway and aberrations in their cell death machinery can result in systemic effects on the immune system. 相似文献
107.
Ying Si Soojin Kim Xiangqin Cui Lei Zheng Shin J. Oh Tina Anderson Mohammad AlSharabati Mohamed Kazamel Laura Volpicelli-Daley Marcas M. Bamman Shaohua Yu Peter H. King 《PloS one》2015,10(9)
We recently identified Smads1, 5 and 8 as muscle biomarkers in human ALS. In the ALS mouse, these markers are elevated and track disease progression. Smads are signal transducers and become activated upon receptor engagement of ligands from the TGF-β superfamily. Here, we sought to characterize ligands linked to activation of Smads in ALS muscle and their role as biomarkers of disease progression. RNA sequencing data of ALS muscle samples were mined for TGF-β superfamily ligands. Candidate targets were validated by qRT-PCR in a large cohort of human ALS muscle biopsy samples and in the G93A SOD1 mouse. Protein expression was evaluated by Western blot, ELISA and immunohistochemistry. C2C12 muscle cells were used to assess Smad activation and induction. TGF-β1, 2 and 3 mRNAs were increased in ALS muscle samples compared to controls and correlated with muscle strength and Smads1, 2, 5 and 8. In the G93A SOD1 mouse, the temporal pattern of TGF-β expression paralleled the Smads and increased with disease progression. TGF-β1 immunoreactivity was detected in mononuclear cells surrounding muscle fibers in ALS samples. In muscle cells, TGF-β ligands were capable of activating Smads. In conclusion, TGF-β1, 2 and 3 are novel biomarkers of ALS in skeletal muscle. Their correlation with weakness in human ALS and their progressive increase with advancing disease in the ALS mouse suggest that they, as with the Smads, can track disease progression. These ligands are capable of upregulating and activating Smads and thus may contribute to the Smad signaling pathway in ALS muscle. 相似文献
108.
109.
We sought to determine whether the orexigenic hormone, ghrelin, is involved in the intrinsic regulation of food choice in rats. Ghrelin would seem suited to serve such a role given that it signals hunger information from the stomach to brain areas important for feeding control, including the hypothalamus and reward system (e.g. ventral tegmental area, VTA). Thus, in rats offered a choice of palatable foods (sucrose pellets and lard) superimposed on regular chow for 2 weeks, we explored whether acute central delivery of ghrelin (intracerebroventricular (ICV) or intra-VTA) is able to redirect their dietary choice. The major unexpected finding is that, in rats with high baseline lard intake, acute ICV ghrelin injection increased their chow intake over 3-fold, relative to vehicle-injected controls, measured at both 3 hr and 6 hr after injection. Similar effects were observed when ghrelin was delivered to the VTA, thereby identifying the VTA as a likely contributing neurobiological substrate for these effects. We also explored food choice after an overnight fast, when endogenous ghrelin levels are elevated, and found similar effects of dietary choice to those described for ghrelin. These effects of fasting on food choice were suppressed in models of suppressed ghrelin signaling (i.e. peripheral injection of a ghrelin receptor antagonist to rats and ghrelin receptor (GHSR) knock-out mice), implicating a role for endogenous ghrelin in the changes in food choice that occur after an overnight fast. Thus, in line with its role as a gut-brain hunger hormone, ghrelin appears to be able to acutely alter food choice, with notable effects to promote “healthy” chow intake, and identify the VTA as a likely contributing neurobiological substrate for these effects. 相似文献