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101.
Intramembranous bone regeneration differs among common inbred mouse strains following marrow ablation
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Meghan M. Moran Amarjit S. Virdi Kotaro Sena Steven R. Mazzone Margaret A. McNulty Dale R. Sumner 《Journal of orthopaedic research》2015,33(9):1374-1381
Various intact and post‐injury bone phenotypes are heritable traits. In this study, we sought to determine if intramembranous bone regeneration following marrow ablation differed among common inbred mouse strains and to identify how early the differences appear. We found a ~four‐fold difference in the regenerated bone volume 21 days after marrow ablation in females from four inbred mouse strains: FVB/N (15.7 ± 8.1%, mean and standard deviation), C3H/He (15.5 ± 4.2%), C57BL/6 (12.2 ± 5.2%), and BALB/c (4.0 ± 4.4%); with BALB/c different from FVB/N (p = 0.007) and C3H/He (p = 0.002). A second experiment showed that FVB/N compared to BALB/c mice had more regenerated bone 7 and 14 days after ablation (p < 0.001), while at 21 days FVB/N mice had a greater fraction of mineralizing surface (p = 0.008) without a difference in mineral apposition rate. Thus, differences among strains are evident early during intramembranous bone regeneration following marrow ablation and appear to be associated with differences in osteogenic cell recruitment, but not osteoblast activity. The amount of regenerating bone was not correlated with other heritable traits such as the intact bone phenotype or soft tissue wound healing, suggesting that there may be independent genetic pathways for these traits. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1374–1381, 2015. 相似文献
102.
R N Doughty S P Wright A Pearl H J Walsh S Muncaster G A Whalley G Gamble N Sharpe 《European heart journal》2002,23(2):139-146
AIMS: To determine the effect of an integrated heart failure management programme, involving patient and family, primary and secondary care, on quality of life and death or hospital readmissions in patients with chronic heart failure. METHODS AND RESULTS: This trial was a cluster randomized, controlled trial of integrated primary/secondary care compared with usual care for patients with heart failure. The intervention involved clinical review at a hospital-based heart failure clinic early after discharge, individual and group education sessions, a personal diary to record medication and body weight, information booklets and regular clinical follow-up alternating between the general practitioner and heart failure clinic. Follow-up was for 12 months. One hundred and ninety-seven patients admitted to Auckland Hospital with an episode of heart failure were enrolled in the study. There was no significant difference between the intervention and control groups for the combined end-point of death or hospital readmission. The physical dimension of quality of life showed a greater improvement in the intervention group from baseline to 12 months compared with the control group (-11.1 vs -5.8 respectively, 2 P=0.015). The main effect of the intervention was attributable to the prevention of multiple admissions (56 intervention group vs 95 control group, 2 P=0.015) and associated reduction in bed days. CONCLUSIONS: This integrated management programme for patients with chronic heart failure improved quality of life and reduced total hospital admissions and total bed days. 相似文献
103.
Prolactin-releasing peptide and its homolog RFRP-1 act in hypothalamus but not in anterior pituitary gland to stimulate stress hormone secretion 总被引:3,自引:0,他引:3
The RF-amide peptides (RFRPs), including prolactin (PRL)-releasing peptide-31 (PrRP-31) and RFRP-1, have been reported to
stimulate stress hormone secretion by either direct pituitary or indirect hypothalamic actions. We examined the possible direct
effects of these peptides on PRL and adrenocorticotropin (adrenocorticotropic hormone [ACTH]) release from dispersed anterior
pituitary cells in culture and on PRL and ACTH secretion following intracerebroventricular (icv) administration in vivo. Neither
peptide significantly altered PRL or ACTH release from cultured pituitary cells (male rat donors). Central administration
of 1.0 and 3.0 nmol of PrRP-31, but only the higher dose of RFRP-1, significantly elevated serum corticosterone levels in
conscious male rats. The effect of PrRP-31 was not blocked by pretreatment (iv) with the corticotropin-releasing hormone (CRH)
antagonist, α-helical CRH 9–41; however, pretreatment of the animals (iv) with an antiserum to CRH significantly lowered the
hypothalamic-pituitary-adrenal axis response to central administration of PrRP-31. On the other hand, the release of PRL was
significantly elevated by 3.0 nmol of RFRP-1, but not PrRP-31, in similarly treated, conscious male rats. Pretreatment with
the catecholamine synthesis inhibitor, α-methyl-para-tyrosine, prevented the stimulation of PRL secretion observed following
central administration of RFRP-1. RFRP-1 similarly did not alter PRL secretion in rats pretreated with the dopamine, D2 receptor blocker, domperidone. These results suggest that the RF-amide peptides are not true neuroendocrine regulators of
stress hormone secretion in the rat but, instead, act centrally to alter the release of neuroendocrine factors that do act
in the pituitary gland to control PRL and ACTH release. In the case of RFRP-1, stimulation of PRL secretion is potentially
owing to an action of the peptide to inhibit dopamine release into the median eminence. The corticosterone secretion observed
following central administration of PrRP-31 does not appear, based on our current results, to be solely owing to an action
of the peptide on CRH-producing neurons but, instead, may be a result of the ability of PrRP-31 to increase as well the exposure
of the corticotrophs in vivo to other ACTH secretagogues, such as oxytocin or vasopressin. 相似文献
104.
105.
Daniel Olson Meghan Birkholz James T. Gaensbauer Edwin J. Asturias James K. Todd 《The American journal of tropical medicine and hygiene》2015,92(5):1067-1069
The Pediatric Health Information System (PHIS) database collects admission, diagnostic, and treatment data among 44 children''s hospitals across the United States (U.S.) and presents an opportunity for travel-associated infectious disease (TAID) surveillance. We calculated cumulative incidence rates among children admitted to 16 PHIS hospitals for dengue, malaria, and typhoid, and pooled TAID using discharge codes from 1999 to 2012. We compared incidence rates before, during, and after the 2007–2009 economic recession. Among 16 PHIS hospitals during the study period (1999–2012), incidence of dengue and pooled TAID (malaria, dengue, typhoid fever) increased significantly, and rates of malaria and typhoid trended upward. Admissions for dengue and pooled TAIDs increased significantly among 16 children''s hospitals across the United States from 1999 to 2012. The PHIS database may provide a useful surveillance tool for TAIDs among children in the United States.International travel to other countries has increased 5% in the United States and 48% worldwide in the last decade, and more travelers visit low- and middle-income countries (LMICs) than ever before.1 As many as 8% of U.S. travelers seek medical care, and many more suffer from milder illness while abroad.2–4 A significant proportion of the 62 million annual U.S. international travelers develops illness after returning to the United States with infections that may be unfamiliar to local health-care providers.5–7 Estimating incidence rates of non-endemic diseases may help public health officials direct educational resources and raise awareness among local practitioners.Currently, surveillance systems for travel-associated infectious diseases (TAIDs) in the United States are limited. Many TAIDs are reportable to state health departments, but reporting is often unreliable.8 The GeoSentinel Surveillance Network (GSSN) is a system of 57 travel disease clinics worldwide, including 15 clinics in the United States. Although the GSSN obtains robust clinical and diagnostic information, it surveys only those seeking care at specialty travel clinics, and only 7% of GSSN patients are children.1The Pediatric Health Information System (PHIS) database was established to collect administrative and financial data from pediatric hospitals across the Unites States. More recently, the database has been augmented (PHIS+) to also collect clinical, laboratory, treatment, and outcome data at multiple health-care settings (inpatient, outpatient, and emergency departments [EDs]) among 44 freestanding children''s hospitals across the United States.9,10 It offers an opportunity for objective hospitalized TAID surveillance among the greater than 5 million children hospitalized annually at these institutions.11 We evaluated the PHIS database as a potential TAID surveillance tool by determining cumulative incidence rates of three TAIDs (malaria, dengue, and typhoid fever) among PHIS hospitals over a 14-year period.A total of 16 PHIS hospitals from geographically diverse metropolitan areas (median population 426,001 people, interquartile range 247,026–757,907 people)12 had non-missing data available during the study period (1999–2012). The metropolitan areas include San Diego, CA; Norfolk, VA; St. Petersberg, FL; Orange County, CA; Corpus Christi, TX; Miami, FL; Denver, CO; Memphis, TN; Chicago, IL; Akron, OH; Little Rock, AR; Columbus, OH; Fort Worth, TX; Omaha, NE; Milwaukee, WI; and St. Louis, MO. All inpatient discharges from these sites with a principal discharge diagnosis (International Classification of Diseases 9 [ICD-9]) code13 for malaria (0840, 0841, 0842, 0843, 0846, 0849), typhoid (0020), and dengue (061) were identified within the PHIS database. Readmissions for the same ICD-9 diagnosis were excluded from the analysis. Cumulative incidence rates of malaria, typhoid, and dengue as well as pooled TAID incidence rates for all three diseases were determined by dividing hospitalized cases by total hospital discharges per year. Individual disease and pooled incidence rates were compared over the study period (1999–2012). We hypothesized that TAID incidence rates may have decreased during the 2007–2009 economic recession due to decreased international travel, and thus, rates for before (1999–2006), during (2007–2009), and after the U.S. economic recession were compared.7,14,15 Categorical variables were compared using χ2 with Fisher''s exact testing when appropriate.The 16 PHIS hospitals represented 2,203,063 pediatric hospital admissions during the study period. Individual and pooled cumulative TAID incidence trended upward from 1999 to 2012, though the trend did not achieve statistical significance (r2 = 0.158). When comparing cumulative incidence rates from before (1999–2006), during, and after (2010–2012) the 2007–2009 economic recession, there was a significant change in incidence rates for dengue (P = 0.016) and pooled TAID (p = 0.009), though all diseases studied showed a similar trend with decreases during the recession and highest rates after (Figure 1
).Open in a separate windowFigure 1.Comparison of pooled and individual travel-associated infectious diseases (TAIDs) in the Pediatric Health Information System (PHIS) database, 1999–2012.
Open in a separate windowCumulative incidence rates (cases per 100,000 admissions) from before (1999–2006), during, and after (2010–2012) the U.S. economic recession.*Reached statistical significance between 2007–2009 and 2010–2012.†Reached statistical significance between 1999–2006 and 2010–2012.We observed an increasing trend of three TAIDs among children in the United States over a 14-year period. Other data support this trend. From 1999 to 2011, passive surveillance from the Centers for Disease Control and Prevention (CDC) showed an increase in malaria incidence of 9%, an increase in typhoid incidence of 50%, and an increase in dengue incidence of 117%.16–18 Although the CDC data indicate a greater increase in TAID incidence than our data, it should be noted that their sample population includes adults in addition to children and their surveillance systems have improved over the same time period, thus increasing disease detection and raising estimated incidence rates. Improved diagnostics, especially for dengue, may have influenced our increased case detection as well.The PHIS database offers several strengths as a surveillance tool. Cases are determined by ICD-9 code, which is consistently documented in hospital records between hospitals and over time, whereas passive reporting may be incomplete.8 The scope of the PHIS database is another significant advantage. Our study with 16 PHIS hospitals demonstrated an upward trend in TAIDs over a time period that included an economic recession. Though our data were limited by low case numbers, the PHIS database has since grown significantly larger, consisting of 44 pediatric hospitals with 605,966 admissions, 2,803,675 ED visits, and 1,504,384 outpatient visits in 2013, reflecting a large proportion of children seeking medical care across the United States. Although our primary aim was to estimate incidence of TAIDs using ICD-9 coding, the PHIS database also offers additional data, including diagnostic tests performed, epidemiologic information, clinical data, and mortality, which can be used for a variety of purposes such as determining risk factors for acquiring disease. Regional data among PHIS hospitals can be compared as well.There are several notable weaknesses to our use of the PHIS database in disease surveillance. Data in the PHIS database are made available every 3 months, so real-time data are unavailable. We analyzed only hospitalization discharge data from selected pediatric hospitals, likely representing a small fraction of all clinical illness in traveling children. We used only principal ICD-9 diagnosis code in our analysis assuming the TAID would be the primary reason for hospitalization. Using all ICD-9 codes as well as including ED and outpatient visits may increase the sensitivity of detection, but coding variation may also bias estimates of disease incidence. ICD-9 codes may also not always reflect a patient''s actual diagnosis, though appropriate laboratory testing for TAIDs is available and should be used in the United States to increase diagnostic accuracy. Typhoid and, more recently, dengue are endemic within the United States, though they remain strongly associated with travel. Another limitation of the PHIS database is that it collects limited epidemiologic data such as travel history. As a result, we were unable to further characterize risk factors for acquiring TAIDs such as type of travel, reason for travel, and immigration status. Although our analysis defined the U.S. economic recession as 2007–2009, the decrease in outbound international travel appears to have continued early into the recovery, reaching a nadir in 2011.7 Given our restricted sample population of 16 pediatric hospitals, we did not perform a comparison of TAID hospitalization incidence using outbound international travel data as an unspecific denominator because it was unlikely to produce meaningful results.In summary, we identified a novel tool for TAID surveillance among children in the United States. Consistent with passive reporting data, the PHIS database demonstrated an increased trend of individual and pooled TAIDs over the last 14 years. The database also demonstrated significantly increased rates in dengue and pooled TAIDs when comparing before, during, and after the 2007–2009 economic recession. The increased incidence rates should remind providers to remain vigilant about TAIDs, especially as outbound U.S. travel continues to increase. Now with 44 participating children''s hospitals across the United States, the PHIS database may provide a useful and objective instrument for disease surveillance, including an assessment of the economic impact of diseases. 相似文献
Table 1
Hospital admission incidence rates of travel-associated infectious diseases (TAIDs) in children before, during, and after the 2007–2009 economic recession.1999–2006 | 2007–2009 | 2010–2012 | |
---|---|---|---|
Malaria | 6.7 | 6.4 | 8.4 |
Typhoid | 5.0 | 4.4 | 7.0 |
Dengue* | 1.1 | 0.6 | 2.5 |
Pooled*† | 12.9 | 11.3 | 18.0 |
106.
Andrew M. Zeiger Meghan E. McGarry Angel C. Y. Mak Vivian Medina Sandra Salazar Celeste Eng Amy K. Liu Sam S. Oh Thomas J. Nuckton Deepti Jain Thomas W. Blackwell Hyun Min Kang Goncalo Abecasis Leandra Cordero Oate Max A. Seibold Esteban G. Burchard Jose Rodriguez‐Santana 《Pediatric pulmonology》2020,55(2):533-540
107.
The association between the acute psychobiological stress response in second trimester pregnant women,amniotic fluid glucocorticoids,and neonatal birth outcome
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108.
109.
Huizhen Wang Melissa Larson Albina Jablonka-Shariff Christopher A. Pearl William L. Miller P. Michael Conn Irving Boime T. Rajendra Kumar 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(15):5735-5740
FSH and luteinizing hormone (LH) are secreted constitutively or in pulses, respectively, from pituitary gonadotropes in many vertebrates, and regulate ovarian function. The molecular basis for this evolutionarily conserved gonadotropin-specific secretion pattern is not understood. Here, we show that the carboxyterminal heptapeptide in LH is a gonadotropin-sorting determinant in vivo that directs pulsatile secretion. FSH containing this heptapeptide enters the regulated pathway in gonadotropes of transgenic mice, and is released in response to gonadotropin-releasing hormone, similar to LH. FSH released from the LH secretory pathway rescued ovarian defects in Fshb-null mice as efficiently as constitutively secreted FSH. Interestingly, the rerouted FSH enhanced ovarian follicle survival, caused a dramatic increase in number of ovulations, and prolonged female reproductive lifespan. Furthermore, the rerouted FSH vastly improved the in vivo fertilization competency of eggs, their subsequent development in vitro and when transplanted, the ability to produce offspring. Our study demonstrates the feasibility to fine-tune the target tissue responses by modifying the intracellular trafficking and secretory fate of a pituitary trophic hormone. The approach to interconvert the secretory fate of proteins in vivo has pathophysiological significance, and could explain the etiology of several hormone hyperstimulation and resistance syndromes.During vertebrate evolution, the female reproductive pattern underwent a remarkable transition from spawning of large number of eggs in primitive species under favorable conditions to more tightly controlled ovarian cycles in higher vertebrates, such that only a limited number (rodents) or a single (human and nonhuman primates) egg is released per cycle (1, 2). Coincident with this event, the single pituitary gonadotropic hormone that exists in primitive vertebrates has given rise to two gonadotropins, FSH and luteinizing hormone (LH), which coordinate gametogenesis and steroidogenesis (3–7). FSH and LH are heterodimeric glycoproteins that contain a common α-subunit and a hormone-specific β-subunit (3). Although synthesized in the same cell, the gonadotrope, FSH is mostly constitutively released in many species, whereas LH is stored in dense core granules (DCGs) and secreted in pulses via the regulated pathway in response to gonadotropin-releasing hormone (GnRH) (8, 9). Although this pattern is evolutionarily conserved, how distinct modes of gonadotropin secretion affect ovarian development and target cell responses remain unclear. Although models in which variations in secretion of gonadotropins have been achieved in vivo (10) and in vitro, including basolateral and apically polarized secretion (11), the in vivo consequences of altered mode of gonadotropin trafficking and release (constitutive vs. regulated) from pituitary are untested. We sought to identify why the two gonadotropins, LH and FSH, expressed in the same pituitary cell have evolved to exit via different routes to regulate ovarian physiology. 相似文献
110.
Jacqueline R. Bullis Meghan R. Fortune Todd J. Farchione David H. Barlow 《Comprehensive psychiatry》2014