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1.
Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献
2.
3.
Dympna Harmey Gudrun Stenbeck Catherine D Nobes Alistair J Lax Agamemnon E Grigoriadis 《Journal of bone and mineral research》2004,19(4):661-670
The role of the Rho-Rho kinase signaling pathway on osteoblast differentiation was investigated using primary mouse calvarial cells. The bacterial toxin PMT inhibited, whereas Rho-ROK inhibitors stimulated, osteoblast differentiation and bone nodule formation. These effects correlated with altered BMP-2 and -4 expression. These data show the importance of Rho-ROK signaling in osteoblast differentiation and bone formation. INTRODUCTION: The signal transduction pathways controlling osteoblast differentiation are not well understood. In this study, we used Pasteurella multocida toxin (PMT), a unique bacterial toxin that activates the small GTPase Rho, and specific Rho inhibitors to investigate the role of Rho in osteoblast differentiation and bone formation in vitro. MATERIALS AND METHODS: Primary mouse calvarial osteoblast cultures were used to investigate the effects of recombinant PMT and Rho-Rho kinase (ROK) inhibitors on osteoblast differentiation and bone nodule formation. Osteoblast gene expression was analyzed using Northern blot and RT-PCR, and actin rearrangements were visualized after phalloidin staining and confocal microscopy. RESULTS: PMT stimulated the proliferation of primary mouse calvarial cells and markedly inhibited the differentiation of osteoblast precursors to bone nodules with a concomitant inhibition of osteoblastic marker gene expression. There was no apparent causal relationship between the stimulation of proliferation and inhibition of differentiation. PMT caused cytoskeletal rearrangements because of activation of Rho, and the inhibition of bone nodules was completely reversed by the Rho inhibitor C3 transferase and partly reversed by inhibitors of the Rho effector, ROK. Interestingly, Rho and ROK inhibitors alone potently stimulated osteoblast differentiation, gene expression, and bone nodule formation. Finally, PMT inhibited, whereas ROK inhibitors stimulated, bone morphogenetic protein (BMP)-2 and -4 mRNA expression, providing a possible mechanism for their effects on bone nodule formation. CONCLUSIONS: These results show that PMT inhibits osteoblast differentiation through a mechanism involving the Rho-ROK pathway and that this pathway is an important negative regulator of osteoblast differentiation. Conversely, ROK inhibitors stimulate osteoblast differentiation and may be potentially useful as anabolic agents for bone. 相似文献
4.
Valery L Feigin Craig S Anderson Anthony Rodgers Neil E Anderson Alistair J Gunn 《Journal of clinical neuroscience》2002,9(5):502-507
Current treatment of acute stroke remains unsatisfactory. This review presents experimental and clinical data which suggest that mild induced hypothermia could be a potent and practicable neuroprotective treatment of acute ischaemic stroke and intracerebral haemorrhage. Hypothermia, if proven to be safe, effective and widely practicable in patients with acute stroke, could have an enormous positive impact on reducing the burden of stroke worldwide. Critical issues that will need to be considered in a well designed randomised controlled trial of induced hypothermia in acute stroke patients are discussed. 相似文献
5.
Steven G. E. Marsh Ekkehard D. Albert Walter F. Bodmer Ronald E. Bontrop Bo Dupont Henry A. Erlich Daniel E. Geraghty John A. Hansen Bernard Mach Wolfgang R. Mayr Peter Parham Effie W. Petersdorf Takehiko Sasazuki Geziena M. Th. Schreuder Jack L. Strominger Arne Svejgaard Paul I. Terasaki 《International journal of immunogenetics》2002,29(6):463-515
6.
E I Traboulsi J C Silva M T Geraghty I H Maumenee D Valle W R Green 《American journal of ophthalmology》1992,113(3):269-280
The eyes of a 22-month-old girl with the cobalamin C complementation type of combined methylmalonic aciduria and homocystinuria were studied with light and electron microscopy. We observed vacuolization of the iris pigment epithelium, loss of photoreceptors in the central 3.3 mm of the macula, partial loss of the nerve fiber and ganglion cell layers between the fovea and optic disk, and partial optic atrophy. The sclera in the posterior pole was thickened with deposition of mucopolysaccharide. Electron microscopy showed inclusions containing fine granular material in conjunctival fibrocytes; corneal epithelium, keratocytes, and endothelial cells; iris pigment epithelium; ganglion cells; retinal pigment epithelium; and choroid and scleral fibrocytes. Enlarged mitochondria and clear vacuoles distended the corneal endothelial cells. We found evidence of possible lysosomal dysfunction and mucopolysaccharide storage, as well as a clinicopathologic correlation of the macular degeneration in this disease. 相似文献
7.
Richard C Oude Voshaar Sube Banerjee Mike Horan Robert Baldwin Neil Pendleton Rebekah Proctor Nick Tarrier Yvonne Woodward Alistair Burns 《The American journal of geriatric psychiatry》2007,15(9):807-814
OBJECTIVE: Depression after hip fracture surgery is prevalent and associated with increased mortality rates and impaired functional recovery. The incidence of new-onset depressive symptoms in patients initially not depressed after hip fracture surgery and their relationship with functional recovery is unknown. METHODS: A cohort of 139 nondepressed elderly patients (>60 years) hospitalized for hip fracture surgery were followed up for six months. Clinically significant depressive symptoms were defined as a score of 7 or more on the 15-item Geriatric Depression Scale. RESULTS: The authors found a cumulative incidence rate of 20.5% adjusted for dropouts. Multiple Cox-regression analyses yielded the presence of subthreshold symptoms of depression, anxiety, pain, and cognitive impairment at baseline, the premorbid level of mobility, and a history of (treated) depression as risk factors for incident depression (p <0.05). A forward, conditional procedure identified postoperative pain (hazard ratio [HR] = 1.32, 95% confidence interval [CI]: 1.14-1.53, Wald chi(2) = 13.57, df = 1, p <0.001) and baseline anxiety (HR = 1.25, 95% CI: 1.08-1.44, Wald chi(2) = 8.86, df = 1, p = 0.003) as the strongest independent risk factors. Incident depression was associated with a less favorable outcome at 3 months follow-up. CONCLUSION: This exploratory study identified two treatable baseline characteristics that predicted incident depression in nondepressed patients after hip-fracture surgery. 相似文献
8.
Alistair Howitt 《British medical journal》2003,326(7399):1134-1135
9.
Dr Alistair J. Cochran 《Pathology international》1998,48(2):168-170
The Association of Directors of Anatomic and Surgical Pathology have developed recommendations for the surgical pathology report for common malignant tumors. The recommendations for cutaneous melanoma are reported herein. 相似文献
10.
Fiona Campbell MD MRCPath John M Geraghty MBBS MRCPath Mark A.C Appleton MBChB MRCPath E.Dillwyn Williams MD FRCP FRCPath Geraint T Williams MD FRCP FRCPath 《Human pathology》1998,29(12):1531-1535
Colorectal tumorigenesis in familial adenomatous polyposis (FAP) results from somatic mutation of either the normal APC allele or another growth control gene in epithelial cells bearing a germline APC defect. The rate at which tumors develop is therefore dependent on the somatic mutation frequency; it is not known whether this is normal or elevated in FAP. We aimed to quantify stem cell somatic mutation in FAP, comparing it with hereditary nonpolyposis colorectal cancer (HNPCC) and Crohn's disease (CD). Stem cell somatic mutation frequency was studied in 47 FAP patients, 5 HNPCC patients, and 13 CD patients, all younger than 49 years, by quantifying crypt-restricted loss of O-acetyltransferase activity in sections of morphologically normal colonic mucosa from individuals heterozygous for this monogenically inherited polymorphism. Median stem cell somatic mutation frequency was significantly higher in FAP than HNPCC (4.2 × 10−4v 1.4 × 10−4, Mann-Whitney U, P < .02). The level in CD (4.0 × 10−4) was similar to FAR Mutated crypts occurred in groups more frequently in FAP (22%) than HNPCC (12%) or CD (10%), suggesting an increase in stem cell division associated with crypt fission in FAP. We conclude that stem cell somatic mutation frequency is raised in non-neoplastic colorectal mucosa in FAR This is probably related to increased stem cell proliferation and contributes to the high rate of tumor formation in this condition. 相似文献