bluuebunny/crossref_metadata_2025 huggingface dataset:
Stronger bone correlates with African admixture in African-American women
Authors: Chen Zhao , Qi Lihong , Beck Thomas J , Robbins John , Wu Guanglin , Lewis Cora E , Cauley Jane A , Wright Nicole C , Seldin Michael F
Published: May 2011

Osteoporosis affects all populations, but the risk for low bone density and fracture varies greatly by self-reported race and ethnicity. In this article, the relationship between measured percent African admixture and hip structural geometry, estimated from the hip structural analysis (HSA) program, was examined in a subcohort of the Women's Health Initiative (WHI). The study sample included 793 African-American women and 8559 non-Hispanic white women. All the participants were postmenopausal, between the ages of 50 and 79 years, at the time of recruitment and were followed for up to 9 years. Bone density and hip geometry were assessed using dual-energy X-ray absorptiometry. African admixture was measured for African Americans using genetic ancestry informative markers. Multiple regression and mixed-effects models were used for cross-sectional and longitudinal analyses, respectively. Covariates assessed from questionnaires and physical measurements were included in the analysis to control for possible confounding effects. The study results show significant correlations between percent of African admixture and HSA assessments. In comparison with non-Hispanic white women, significantly greater bone strength, as indicated by higher hip bone mineral density and stronger hip geometry, in women with higher African admixture was observed. However, women with higher percent African admixture had larger reductions in bone strength than non-Hispanic white women during the follow-up. © 2011 American Society for Bone and Mineral Research
The renin-angiotensin system, blood pressure, and heart structure in patients with hereditary vitamin D–resistance rickets (HVDRR)
Authors: Tiosano Dov , Schwartz Yitzchak , Braver Yulia , Hadash Amir , Gepstein Vardit , Weisman Yosef , Lorber Avraham
Published: May 2011

Vitamin D deficiency has been linked to hypertension and an increased prevalence of cardiovascular risk factors and disease. Studies in vitamin D receptor knockout (VDR KO) mice revealed an overstimulated renin-angiotensin system (RAS) and consequent high blood pressure and cardiac hypertrophy. VDR KO mice correspond phenotypically and metabolically to humans with hereditary 1,25-dihydroxyvitamin D–resistant rickets (HVDRR). There are no data on the cardiovascular system in human HVDRR. To better understand the effects of vitamin D on the human cardiovascular system, the RAS, blood pressure levels, and cardiac structures were examined in HVDRR patients. Seventeen patients (9 males, 8 females, aged 6 to 36 years) with hereditary HVDRR were enrolled. The control group included age- and gender-matched healthy subjects. Serum calcium, phosphorous, creatinine, 25-hydroxyvitamin D [25(OH)D],1,25-dihydroxyvitamin D3 [1,25(OH)2D3], parathyroid hormone (PTH), plasma rennin activity (PRA), aldosterone, angiotensin II (AT-II), and angiotensin-converting enzyme (ACE) levels were determined. Ambulatory 24-hour blood pressure measurements and echocardiographic examinations were performed. Serum calcium, phosphorus, and alkaline phosphatase values were normal. Serum 1,25(OH)2D3 and PTH but not PRA and ACE levels were elevated in the HVDRR patients. AT-II levels were higher than normal in the HVDRR patients but not significantly different from those of the controls. Aldosterone levels were normal in all HVDRR patients. No HVDRR patient had hypertension or echocardiographic pathology. These findings reveal that 6- to 36-year-old humans with HVDRR have normal renin and ACE activity, mild but nonsignificant elevation of AT-II, normal aldosterone levels, and no hypertension or gross heart abnormalities. © 2011 American Society for Bone and Mineral Research
FGF-23/Klotho signaling is not essential for the phosphaturic and anabolic functions of PTH
Authors: Yuan Quan , Sato Tadatoshi , Densmore Michael , Saito Hiroaki , Schüler Christiane , Erben Reinhold G , Lanske Beate
Published: May 2011

Parathyroid hormone (PTH) is widely recognized as a key regulator of mineral ion homeostasis. Daily intermittent administration of PTH is the only currently available anabolic therapy for bone disorders such as osteoporosis. Recent studies have shown that PTH increases transcription and secretion of fibroblast growth factor 23 (FGF-23), another important regulator of phosphate homeostasis and skeletal metabolism. However, the full relationship between PTH and FGF-23 is largely unknown. This study evaluated the effect of FGF-23/Klotho signaling on the phosphaturic and anabolic functions of PTH. Eight-day-old wild-type (WT) Fgf23−/− and Kl−/− mice were injected with 100 µg/kg PTH(1–34) or vehicle daily for a 2-week-period and then euthanized. Intermittent injection of PTH successfully reduced the serum phosphate levels and reversed the hyperphosphatemia of Fgf23−/− and Kl−/− mice. Bone changes were analyzed in the distal femur metaphysis by peripheral quantitative computed tomography (pQCT), micro–computed tomography (µCT), and histomorphometry. PTH treatment induced substantial increases in bone mineral density (BMD) and trabecular bone volume in each mouse genotype. Expression of osteoblastic marker genes, including Runx2, Col1, Alp, Ocn, and Sost, was similarly altered. In addition, primary osteoblasts were isolated and treated with 100 nM PTH in vitro. PTH treatment similarly induced cAMP accumulation and phosphorylation of ERK1/2 and CREB in the osteoblasts from each genotype. Taken together, our results demonstrate that FGF-23/Klotho signaling is not essential for the phosphaturic and anabolic functions of PTH, suggesting that PTH can function as a therapeutic agent to improve the skeletal quality of patients even in the presence of abnormal serum FGF-23 levels. © 2011 American Society for Bone and Mineral Research
The relationship between calcium and the metabolism of plasma membrane phospholipids in hemolysis induced by brown spider venom phospholipase‐D toxin
Authors: Chaves‐Moreira Daniele , Souza Fernanda N. , Fogaça Rosalvo T.H. , Mangili Oldemir C. , Gremski Waldemiro , Senff‐Ribeiro Andrea , Chaim Olga M. , Veiga Silvio S.
Published: May 2011

Brown spider venom phospholipase‐D belongs to a family of toxins characterized as potent bioactive agents. These toxins have been involved in numerous aspects of cell pathophysiology including inflammatory response, platelet aggregation, endothelial cell hyperactivation, renal disorders, and hemolysis. The molecular mechanism by which these toxins cause hemolysis is under investigation; literature data have suggested that enzyme catalysis is necessary for the biological activities triggered by the toxin. However, the way by which phospholipase‐D activity is directly related with human hemolysis has not been determined. To evaluate how brown spider venom phospholipase‐D activity causes hemolysis, we examined the impact of recombinant phospholipase‐D on human red blood cells. Using six different purified recombinant phospholipase‐D molecules obtained from a cDNA venom gland library, we demonstrated that there is a correlation of hemolytic effect and phospholipase‐D activity. Studying recombinant phospholipase‐D, a potent hemolytic and phospholipase‐D recombinant toxin (LiRecDT1), we determined that the toxin degrades synthetic sphingomyelin (SM), lysophosphatidylcholine (LPC), and lyso‐platelet‐activating factor. Additionally, we determined that the toxin degrades phospholipids in a detergent extract of human erythrocytes, as well as phospholipids from ghosts of human red blood cells. The products of the degradation of synthetic SM and LPC following recombinant phospholipase‐D treatments caused hemolysis of human erythrocytes. This hemolysis, dependent on products of metabolism of phospholipids, is also dependent on calcium ion concentration because the percentage of hemolysis increased with an increase in the dose of calcium in the medium. Recombinant phospholipase‐D treatment of human erythrocytes stimulated an influx of calcium into the cells that was detected by a calcium‐sensitive fluorescent probe (Fluo‐4). This calcium influx was shown to be channel‐mediated rather than leak‐promoted because the influx was inhibited by L‐type calcium channel inhibitors but not by a T‐type calcium channel blocker, sodium channel inhibitor or a specific inhibitor of calcium activated potassium channels. Finally, this inhibition of hemolysis following recombinant phospholipase‐D treatment occurred in a concentration‐dependent manner in the presence of L‐type calcium channel blockers such as nifedipine and verapamil. The data provided herein, suggest that the brown spider venom phospholipase‐D‐induced hemolysis of human erythrocytes is dependent on the metabolism of membrane phospholipids, such as SM and LPC, generating bioactive products that stimulate a calcium influx into red blood cells mediated by the L‐type channel. J. Cell. Biochem. 112: 2529–2540, 2011. © 2011 Wiley‐Liss, Inc.
BMP‐2 suppresses renal interstitial fibrosis by regulating epithelial–mesenchymal transition
Authors: Yang Yu‐Lin , Ju Hong‐Zen , Liu Shu‐Fen , Lee Tao‐Chen , Shih Yuan‐Wei , Chuang Lea‐Yea , Guh Jinn‐Yuh , Yang Ya‐Ying , Liao Tung‐Nan , Hung Tsung‐Jen , Hung Min‐Yuan
Published: May 2011

Dysregulation of epithelial‐to‐mesenchymal transition (EMT) may contribute to renal fibrogenesis. Our previous study indicated that bone morphogenetic protein‐2 (BMP‐2) significantly reversed transforming growth factor (TGF)‐β1‐induced renal interstitial fibrosis. In this study, we examined the underlying mechanism and elucidate the regulation of EMT process under BMP‐2 treatment. Cultured renal interstitial fibroblast (NRK‐49F) was treated with TGF‐β1 (10 ng/ml) with or without BMP‐2 (10–250 ng/ml) for 24 h. The expression of α‐smooth muscle actin (α‐SMA), E‐cadherin, fibronectin, or Snail transcriptional factors was analyzed by immunofluorescence staining or Western blotting. Cell migration was analyzed by wound‐healing assay. NRK‐49F treated with TGF‐β1 induced significant EMT including upregulatioin of α‐SMA, fibronectin, and snail proteins and down‐regulation of E‐cadherin. Interestingly, co‐treatment with BMP‐2 dose‐dependently reversed TGF‐β1‐induced cellular fibrosis, cell migration, and above EMT change. The above effect was closely correlated with Snail since BMP‐2 dose‐ and time‐course dependently induced a significant decrease in the level of Snail. Moreover, Snail siRNA significantly reversed TGF‐β1‐induced increases in the level of α‐SMA and fibronectin (intracellular and extracellular). We suppose that BMP‐2 have the potential to attenuate TGF‐β1‐induced renal interstitial fibrosis by attenuating Snail expression and reversing EMT process. J. Cell. Biochem. 112: 2558–2565, 2011. © 2011 Wiley‐Liss, Inc.
Alkaline stress‐induced autophagy is mediated by mTORC1 inactivation
Authors: Suk Jinkyu , Kwak Sang Su , Lee Jae Ho , Choi Ji Hye , Lee Sang‐Hee , Lee Dong Hwan , Byun Boohyeong , Lee Geon‐Hyoung , Joe Cheol O.
Published: May 2011

The activation of autophagic pathway by alkaline stress was investigated. Various types of mammalian cells were subjected to alkaline stress by incubation in bicarbonate buffered media in humidified air containing atmospheric 0.04% CO2. The induction of autophagy following alkaline stress was evaluated by assessing the conversion of cytosolic LC3‐I into lipidated LC3‐II, the accumulation of autophagosomes, and the formation of autolysosomes. Colocalization of GFP‐LC3 with endolysosomal marker in HeLa GFP‐LC3 cells undergoing autophagic process by alkaline stress further demonstrates that autophagosomes triggered by alkaline stress matures into autolysosomes for the lysosome dependent degradation. We found that the inactivation of mTORC1 is important for the pathway leading to the induction of autophagy by alkaline stress since the expression of RhebQ64L, a constitutive activator of mTORC1, downregulates the induction of autophagy after alkaline stress in transfected human 293T cells. These results imply that activation of autophagic pathway following the inactivation of mTORC1 is important cellular events governing alkaline stress‐induced cytotoxicity and clinical symptoms associated with alkalosis. J. Cell. Biochem. 112: 2566–2573, 2011. © 2011 Wiley‐Liss, Inc.
The role of Lrp5/6 in cardiac valve disease: LDL‐density‐pressure theory
Authors: Rajamannan Nalini M.
Published: May 2011

Atherosclerosis and osteoporosis are the leading causes of mortality and morbidity in the World. Recent epidemiologic studies have demonstrated that these disease processes develop in parallel. Evidence indicates that hyperlipidemia plays a paradoxical role in both disease processes. However, the mechanism is not understood. This prospectus hypothesizes the role of lipids activate atherosclerosis within the bone and the heart to initiate the development of diseases in both of these tissues. The Prospectus on the Lrp 5/6 receptors provides a foundation for the mechanisms involved in the Lrp5/6 mediated disease biology. The LDL‐Density‐Pressure theory: the Role of Lrp5/6 provides a biological and a hemodynamic approach towards understanding the development of valvular heart disease and the implications in the field of bone molecular biology. This prospectus will review the current literature, provide a basis for the development of valve disease and indicate future therapeutic pathways for this disease process in the future. J. Cell. Biochem. 112: 2222–2229, 2011. © 2011 Wiley‐Liss, Inc.
Dispositional optimism buffers combat veterans from the negative effects of warzone stress on mental health symptoms and work impairment
Authors: Thomas Jeffrey L. , Britt Thomas W. , Odle‐Dusseau Heather , Bliese Paul D.
Published: May 2011

The study examined dispositional optimism s role in buffering the effect of warzone stress on mental health symptoms and mental health symptoms on work impairment. A total of 2,439 soldiers from an active‐duty brigade combat team were surveyed following a 12‐month deployment to Iraq. Posttraumatic stress disorder (PTSD) symptoms, depression symptoms, combat exposure, deployment demands, and work impairment were measured. Soldiers higher in dispositional optimism showed weaker relationships between combat exposure and PTSD symptoms, and between deployment demands and PTSD and depression symptoms. Dispositional optimism also buffered mental health symptom effects on work impairment. Dispositional optimism may protect soldiers from warzone stress and mental health symptoms. Potential mechanisms explaining how dispositional optimism may serve as a protective factor are discussed. © 2011 Wiley Periodicals, Inc. J Clin Psychol 67:1–15, 2011.
Employee voice behavior: A meta‐analytic test of the conservation of resources framework
Authors: Ng Thomas W. H. , Feldman Daniel C.
Published: May 2011

Although voice (i.e. expressing change‐oriented ideas and suggestions) has frequently been investigated as a way for workers to reciprocate to their employers for the positive treatment they receive, much less is known about how workers use voice to deal with stress. This study takes a conservation of resources perspective to examine the relationships among workplace stress, voice behavior, and job performance. We first examined the strength of relationships of three major groups of workplace stressors and strains (job based, social based, and organization based) with voice behavior. We then examined the relationships of voice behavior with performance variables (e.g. in‐role performance and creativity) to investigate how voice may help workers preserve or accumulate resources to enhance their performance. The meta‐analytic findings presented here provide support for a negative relationship between workplace stress and voice and a positive relationship between voice behavior and performance outcomes. Copyright © 2011 John Wiley & Sons, Ltd.
Antitumor effects of telomerase inhibitor TMPyP4 in osteosarcoma cell lines
Authors: Fujimori Jun , Matsuo Toshihiro , Shimose Shoji , Kubo Tadahiko , Ishikawa Masakazu , Yasunaga Yuji , Ochi Mitsuo
Published: May 2011

Telomere studies in carcinomas have been extensively reported for prognostic utility and effective methods for targeting telomerase therapy has been described, but efficacy of telomerase inhibitor remained unknown in sarcoma cells. In this study, we investigated the effects of telomerase inhibitor cationic porphyrin TMPyP4 on telomerase activity, telomere length, cell growth, and apoptosis in osteosarcoma cell lines. TMPyP4 significantly inhibited telomerase activity in telomerase positive HOS and Saos‐2, but not in MG‐63. TMPyP4 significantly induced telomere shortening, and inhibition of the cell growth in HOS and Saos‐2 with over 17% apoptosis rates. In terms of MG‐63, TMPyP4 did not induce inhibition of both telomerase activity and cell growth, although it induced significant telomere shortening. Telomere length after treatment was 5.60 kb in HOS, 4.00 kb in Saos‐2, and 9.89 kb in MG‐63. These results may suggest that both telomerase activity loss and sufficient telomere shortening are necessary to inhibit cell growth in telomerase positive osteosarcoma cells. TMPyP4 did not induced telomere shortening but significantly inhibited the growth with 22.6% apoptosis rate in telomerase negative with extremely longer telomere‐U2OS, may indicating the antitumor effect of TMPyP4 may be related to DNA damage including telomere dysfunction through G‐quadruplex stabilization, independent on telomere length. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:1707–1711, 2011
Nanocomposite therapy as a more efficacious and less inflammatory alternative to bone morphogenetic protein‐2 in a rodent arthrodesis model
Authors: Hsu Wellington K. , Polavarapu Mahesh , Riaz Rehan , Roc Gilbert C. , Stock Stuart R. , Glicksman Zachary S. , Ghodasra Jason H. , Hsu Erin L.
Published: May 2011

The use of recombinant human bone morphogenetic protein‐2 (rhBMP‐2) in spine fusion has led to concerns regarding a potential accompanying inflammatory response. This study evaluates a combination therapy (TrioMatrix®; Pioneer Surgical, Inc., Marquette, MI) comprised of a demineralized bone matrix (DBM), hydroxyapatite, and a nanofiber‐based collagen scaffold in a rodent spine fusion model. Thirty‐six athymic rats that underwent a posterolateral intertransverse spinal fusion were randomly assigned to 1 of 5 treatment groups: absorbable collagen sponge alone (ACS, negative control), 10 µg rhBMP‐2 on ACS (positive control), TrioMatrix®, Grafton® (Osteotech, Inc., Eatontown, NJ), and DBX® (Synthes, Inc., West Chester, PA). Both TrioMatrix® and rhBMP‐2‐treated animals demonstrated 100% fusion rates as graded by manual palpation scores 8 weeks after implantation. This rate was significantly greater than those of the ACS, Grafton®, and DBX® groups. Notably, the use of TrioMatrix® as evaluated by microCT quantification led to a greater fusion mass volume when compared to all other groups, including the rhBMP‐2 group. T2‐weighted axial MRI images of the fusion bed demonstrated a significant host response associated with a large fluid collection with the use of rhBMP‐2; this response was significantly reduced with the use of TrioMatrix®. Our results therefore demonstrate that a nanocomposite therapy represents a promising, cost‐effective bone graft substitute that could be useful in spine fusions where BMP‐2 is contraindicated. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1812–1819, 2011
Calcification in human intervertebral disc degeneration and scoliosis
Authors: Hristova Gergana I. , Jarzem Peter , Ouellet Jean A. , Roughley Peter J. , Epure Laura M. , Antoniou John , Mwale Fackson
Published: May 2011

Calcification is a pathological process that may lead to impairment of nutrient supply and disc metabolism in degenerative and scoliotic intervertebral discs (IVDs). The purpose of this study was to assess the calcification potential of IVDs in degenerative disc disease (DDD) and adolescent idiopathic scoliosis (AIS). For this purpose, 34 IVDs from 16 adult patients with DDD and 25 IVDs from 9 adolescent patients with AIS were obtained at surgery. The concave and convex parts of the scoliotic discs were analyzed separately. Von Kossa staining was performed to visualize calcium deposits, while type X collagen (COL X) expression associated with endochondral ossification was measured by immunohistochemistry. Alkaline phosphatase activity and calcium and inorganic phosphate concentrations were used as indicators of calcification potential. Results showed the presence of calcium deposits and COL X in degenerative and scoliotic IVDs, but not in control discs, and the level of the indicators of calcification potential was consistently higher in degenerative and scoliotic discs than in control discs. The results suggest that disc degeneration in adults is associated with ongoing mineral deposition and that mineralization in AIS discs might reflect a premature degenerative process. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1888–1895, 2011
Relationship of donor variables and graft dimension on biomechanical performance of femoral ring allograft
Authors: Hart Robert A. , Daniels Alan H. , Bahney Timothy , Tesar Jeremy , Sales Jonathan Rafe , Bay Brian
Published: May 2011

Structural femoral ring allograft is commonly used in interbody spinal arthrodesis. Fractures of implanted femoral ring allograft have been reported. Data to guide donor screening and tissue processing by allograft tissue banks for factors that affect graft strength are incomplete. Fresh frozen human femora from 34 cadaveric donors were sectioned into ten 20‐mm thick specimens. Bone mineral density (BMD), donor age, and graft dimensions were recorded for each specimen. Three hundred twenty‐seven specimens were tested in quasi‐static axial compression. Linear regression models compared load to failure with BMD, sex‐specific donor age, minimum/maximum cortical wall thickness, and minimum/maximum outer ring diameter. Correlations between minimum and maximum cortical wall thickness and load to failure were significant (r = 0.73, p < 0.001 and r = 0.74, p < 0.001, respectively). BMD showed a weaker negative correlation with load to failure (r = −0.11, p = 0.05). Correlations between load to failure and minimum and maximum outer ring diameter and age (r = 0.06, p = 0.31) were not significant. We found that the minimum and maximum cortical wall thicknesses of femoral ring allograft are strongly correlated with the axial compressive load to failure of the graft. Other tested parameters did not prove to be effective predictors of resistance to axial loading. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1840–1845, 2011
Palaeoproductivity evolution in the centre of the western Pacific warm pool during the last 250 ka
Authors: Li Tiegang , Zhao Jingtao , Nan Qingyun , Sun Rongtao , Yu Xinke
Published: May 2011

To reconstruct the palaeoproductivity evolution history of the centre of the western Pacific warm pool (WPWP) over the last 250 ka, multi‐proxies were analysed in sediment core WP7 recovered from the Ontong–Java Plateau. Palaeoproductivity evolution at the centre of the WPWP during the last 250 ka is closely related to glacial–interglacial cycles and the insolation controlled by precession. The glacial higher primary productivity relative to the interglacial conditions could have resulted from both thermocline shoaling associated with persistent El Niňo‐like conditions and the increased influx of dust resulting from intensified winter monsoon together with important changes in the thermocline. The minimum primary productivity values during the last three terminations could be resulted from deglacial thermocline deepening and intensified stratification associated with persistent La Niña‐like conditions, and the concurrent Neogloboquadrina dutertrei δ13C minimum events probably reflect the chemical signatures of Subantarctic Mode Water and Antarctic Intermediate Water. In addition, primary productivity values are also controlled by the thermocline variations resulting from El Niño/La Niña‐Southern Oscillation processes responding to precession forcing, and lead the δ18O by about 4 ka. The 33.1 ka, 19 ka and “half‐precession” periods are prominent in the palaeoproductivity records. Copyright © 2011 John Wiley & Sons, Ltd.
Poorly differentiated adenocarcinoma arising from a cervical bronchial cyst
Authors: Calzada Audrey P. , Wu Winnie , Salvado Amanda R. , Lai Chi K. , Berke Gerald S.
Published: May 2011

Bronchogenic cysts with malignant change are rarely reported. We describe a case of poorly differentiated adenocarcinoma arising from a cervical bronchial cyst in a patient presenting with a thyroid mass, cervical lymphadenopathy, and initial biopsy suggestive of papillary thyroid carcinoma. The clinical presentation, intraoperative findings, radiographic images, and pathology slides are presented. To our knowledge, this is the first report of a poorly differentiated adenocarcinoma arising from a bronchial cyst in the cervical region.
Bell's palsy during pregnancy: Is it associated with adverse perinatal outcome?
Authors: Katz Ariel , Sergienko Ruslan , Dior Uri , Wiznitzer Arnon , Kaplan Daniel M. , Sheiner Eyal
Published: May 2011

Objective:

To determine whether an association exists between Bell's palsy during pregnancy and adverse perinatal outcomes.

Methods:

A retrospective study comparing all singleton pregnancies of patients with and without Bell's palsy was conducted. Multiple logistic regression model was performed to control for confounders.

Results:

Out of 242,216 deliveries, 0.017% (n = 42) were diagnosed with Bell's palsy during pregnancy. Risk factors for Bell's palsy were chronic hypertension (9.5% vs. 1.5%, P < .001) and maternal obesity (7.1% vs. 0.8%, P < .001). Patients with Bell's palsy during pregnancy had higher rates of severe preeclampsia (9.5% vs. 1.1%, P < .001) and Cesarean deliveries (31.0% vs. 13.3%, P = .001) compared to the comparison group. In contrast, no significant association was documented between Bell's palsy and adverse perinatal outcomes such as low Apgar scores (<7) at 5 minutes (4.8% vs. 3.1%; P = .524) and perinatal mortality (2.4% vs. 1.4%; P = .57). Using multivariable analysis, controlling for confounders such as maternal age, fertility treatments, and ethnicity, Bell's palsy during pregnancy was significantly associated with obesity (odds ratio [OR] = 9.08 95% confidence interval [CI] 2.8–29.46; P < .001), chronic hypertension (OR = 6.69 95% CI 2.38–18.76; P < .001), and severe preeclampsia (OR = 9.46 95% CI 3.37–26.53; P < .001).

Conclusions:

Chronic hypertension and obesity are independent risk factors for Bell's palsy. Bell's palsy during pregnancy is significantly associated with severe preeclampsia. Nevertheless, no significant association exists between Bell's palsy and adverse perinatal outcomes.
Use of an upper midline incision for living donor partial hepatectomy: A series of 143 consecutive cases
Authors: Lee Kwang-Woong , Kim Seong Hoon , Han Sung-Sik , Kim Young-Kyu , Cho Seong Yeon , You Tae , Park Sang-Jae
Published: May 2011

Over a period of 2 years, we used an upper midline incision (UMI) without laparoscopic assistance in 143 consecutive living donor partial hepatectomy (LDPH) procedures, regardless of the graft type or the donor age, sex, body mass index, or body shape. Here we report surgical recommendations based on our experience with the use of UMIs in this context. The celiac axis (CA) depth ratio (the depth-to-width ratio for the trunk at the CA) was measured to define the shape of the abdominal cavity. A questionnaire was used to assess satisfaction and cosmetic outcomes in this population of donors. One hundred forty-one of the grafts (98.6%) were right grafts or extended right grafts; there were no donor deaths. The mean time of the operation up to graft retrieval in 141 right side grafts was 3 hours 1 minute. All donors recovered fully and returned to their previous activities. Major complications occurred in 9 patients (6.4%) and included reoperation due to bleeding (4), the insertion of a percutaneous drain (4), and rhabdomyolysis (1). Male sex, a large graft (>900 kg), a fatty liver (large fatty changes ≥ 10%), and a deep truncal cavity (a CA depth ratio > 0.35) were significant risk factors for a long graft retrieval time. The use of a wound protector significantly reduced wound complications. The cosmetic outcomes were more satisfactory when a UMI preceded partial hepatectomy instead of a conventional J-shaped incision (P = 0.01). In conclusion, a UMI without laparoscopic assistance can be safely used for LDPH, regardless of the graft type or the donor characteristics. However, the procedure after a UMI is more difficult in male donors with large fatty livers and deep truncal cavities. Accordingly, these features can be used as exclusion criteria for surgeons not accustomed to this modified procedure. Liver Transpl 17:969–975, 2011. © 2011 AASLD.
An event of tail strike of an aircraft due to terrain‐induced wind shear at the Hong Kong International Airport
Authors: Chan P. W.
Published: May 2011

In the morning of 5 March 2010, an aircraft experienced tail strike when it departed from the south runway of the Hong Kong International Airport to the west. This paper documents the meteorological conditions in the tail strike event, and discusses the alerting and the forecasting aspects of the event. Based on the analysis of the aircraft manufacturer, the tail strike is believed to arise from significant wind shear (headwind loss) experienced by the aircraft. By analysing the surface and the LIDAR observations, it appears that the significant wind shear is related to disruption of the background southwesterly flow by the complex terrain near the airport. From the surface observations, there is a microscale cyclone at the western part of the south runway. The radial velocity image of the LIDAR also depicts an area of reverse flow in that region against the background southerly flow. The alerting of the wind shear based on the two wind shear alerting algorithms developed by the Hong Kong Observatory is discussed, and it turns out that the anemometer‐based wind shear algorithm could successfully capture this wind shear occurring close to the ground. On the other hand, due to geometrical constraint, the LIDAR does not pick up the headwind loss experienced by the aircraft. The forecasting of this wind shear event is considered by performing high resolution (down to a horizontal resolution of 50 m) using a mesoscale numerical weather prediction model. The simulated headwind profile at the event time is generally consistent with the aircraft data, though the headwind loss in the simulation is smaller than the reality. Together with the forecast wind gusts, it may be possible to alert the aviation weather forecaster at an earlier time about the occurrence of terrain‐induced wind shear over the south runway in this particular event. Copyright © 2011 Royal Meteorological Society
Changes in streamflow regime as indicator of upstream urbanization in a humid tropical river basin
Authors: George Celine , Jayakumar K. V. , James E. J.
Published: May 2011

Changes in streamflow in the Meenachil river basin, Kerala, are assessed at two upstream gauging stations located at Palai and Cheripad and one downstream gauging station at Peroor to understand changes in flows due to upstream urbanization. An increase of 14% in the population and 46% in the number of housing units have been observed in the entire study area during the last two decades, indicating increase in urbanization. Time series analysis of 29 years data shows an increasing trend at Peroor at 2.8% per year for total flow and 5.2% for peak flow, which indicates the effect of urban land use. There has been a decreasing trend in the flows at 2% at the upstream gauging stations of the river basin. The frequency of occurrence of flows are observed to be increasing at Peroor due to urbanization which brings down vegetation, enhances the impervious area and contributes to fast draining of stormwater. The decrease in both the flow and its frequency of occurrence at the upstream stations are due to the increase in area under plantation crops and also the soil and water conservation works attempted in the area. Copyright © 2011 Royal Meteorological Society
The statistical pitfalls of the partially randomized preference design in non‐blinded trials of psychological interventions
Authors: Gemmell Isla , Dunn Graham
Published: May 2011

In a partially randomized preference trial (PRPT) patients with no treatment preference are allocated to groups at random, but those who express a preference receive the treatment of their choice. It has been suggested that the design can improve the external and internal validity of trials. We used computer simulation to illustrate the impact that an unmeasured confounder could have on the results and conclusions drawn from a PRPT. We generated 4000 observations (“patients”) that reflected the distribution of the Beck Depression Index (DBI) in trials of depression. Half were randomly assigned to a randomized controlled trial (RCT) design and half were assigned to a PRPT design. In the RCT, “patients” were evenly split between treatment and control groups; whereas in the preference arm, to reflect patient choice, 87.5% of patients were allocated to the experimental treatment and 12.5% to the control. Unadjusted analyses of the PRPT data consistently overestimated the treatment effect and its standard error. This lead to Type I errors when the true treatment effect was small and Type II errors when the confounder effect was large. The PRPT design is not recommended as a method of establishing an unbiased estimate of treatment effect due to the potential influence of unmeasured confounders. Copyright © 2011 John Wiley & Sons, Ltd.
Methods of the Pharmacological Imaging of the Cannabinoid System (PhICS) study: towards understanding the role of the brain endocannabinoid system in human cognition
Authors: van Hell Hendrika H. , Bossong Matthijs G. , Jager Gerry , Kahn René S. , Ramsey Nick F.
Published: May 2011

Various lines of (pre)clinical research indicate that cannabinoid agents carry the potential for therapeutic application to reduce symptoms in several psychiatric disorders. However, direct testing of the involvement of cannabinoid brain systems in psychiatric syndromes is essential for further development. In the Pharmacological Imaging of the Cannabinoid System (PhICS) study, the involvement of the endocannabinoid system in cognitive brain function is assessed by comparing acute effects of the cannabinoid agonist Δ9‐tetrahydrocannabinol (THC) on brain function between healthy controls and groups of psychiatric patients showing cognitive dysfunction. This article describes the objectives and methods of the PhICS study and presents preliminary results of the administration procedure on subjective and neurophysiological parameters. Core elements in the methodology of PhICS are the administration method (THC is administered by inhalation using a vaporizing device) and a comprehensive use of pharmacological magnetic resonance imaging (phMRI) combining several types of MRI scans including functional MRI (fMRI), Arterial Spin Labeling (ASL) to measure brain perfusion, and resting‐state fMRI. Additional methods like neuropsychological testing further specify the exact role of the endocannabinoid system in regulating cognition. Preliminary results presented in this paper indicate robust behavioral and subjective effects of THC. In addition, fMRI paradigms demonstrate activation of expected networks of brain regions in the cognitive domains of interest. The presented administration and assessment protocol provides a basis for further research on the involvement of the endocannabionoid systems in behavior and in psychopathology, which in turn may lead to development of therapeutic opportunities of cannabinoid ligands. Copyright © 2011 John Wiley & Sons, Ltd.
Smoking cessation in primary care – a randomized controlled trial of bupropione, nicotine replacements, CBT and a minimal intervention
Authors: Wittchen Hans‐Ulrich , Hoch Eva , Klotsche Jens , Muehlig Stephan
Published: May 2011

Background/aims: Smoking cessation has been shown to be effective in randomized controlled trials. It is unclear though, whether interventions also work in routine primary care.

Methods: In 167 primary care settings we conducted a randomized four‐armed smoking cessation trial to examine the efficacy of a minimal intervention (MI; n = 81), cognitive‐behavioral therapy (CBT; n = 175), bupropion (BUP; n = 108) and nicotine replacements (NRT; n = 103). Overall, 467 current smokers were enrolled. Abstinence rates at the end of treatment (12 weeks) were 32.8% for MI patients, 34.8% for CBT, 35.3% for NRT, and 46.5% for BUP patients (ITT, intention to treat) (no differential effects). Retention rates were highest in the BUP group (59.3%) and lowest in the NRT group (50.5%). Completer findings were: MI, 56.4%; CBT, 64%; BUP, 79.3%; NRT, 69.2% (LOCF, lost to follow‐up). No serious adverse events occurred during or after the medication phase. At 12‐month follow‐up continuous abstinence rates were: BUP, 29.0%; CBT, 20.9%; NRT, 29.6%; MI, 29.6%.

Conclusion: Our findings suggest that established smoking cessation treatments are effective when applied by non‐specialist primary care physicians. Our data supports a structured, multimodal treatment structure as core ingredient of successful smoking cessation in primary care. Copyright © 2011 John Wiley & Sons, Ltd.
Multiple imputation by chained equations: what is it and how does it work?
Authors: Azur Melissa J. , Stuart Elizabeth A. , Frangakis Constantine , Leaf Philip J.
Published: May 2011

Multivariate imputation by chained equations (MICE) has emerged as a principled method of dealing with missing data. Despite properties that make MICE particularly useful for large imputation procedures and advances in software development that now make it accessible to many researchers, many psychiatric researchers have not been trained in these methods and few practical resources exist to guide researchers in the implementation of this technique. This paper provides an introduction to the MICE method with a focus on practical aspects and challenges in using this method. A brief review of software programs available to implement MICE and then analyze multiply imputed data is also provided. Copyright © 2011 John Wiley & Sons, Ltd.
Missing value imputation in longitudinal measures of alcohol consumption
Authors: Grittner Ulrike , Gmel Gerhard , Ripatti Samuli , Bloomfield Kim , Wicki Matthias
Published: May 2011

Attrition in longitudinal studies can lead to biased results. The study is motivated by the unexpected observation that alcohol consumption decreased despite increased availability, which may be due to sample attrition of heavy drinkers. Several imputation methods have been proposed, but rarely compared in longitudinal studies of alcohol consumption. The imputation of consumption level measurements is computationally particularly challenging due to alcohol consumption being a semi‐continuous variable (dichotomous drinking status and continuous volume among drinkers), and the non‐normality of data in the continuous part. Data come from a longitudinal study in Denmark with four waves (2003–2006) and 1771 individuals at baseline. Five techniques for missing data are compared: Last value carried forward (LVCF) was used as a single, and Hotdeck, Heckman modelling, multivariate imputation by chained equations (MICE), and a Bayesian approach as multiple imputation methods. Predictive mean matching was used to account for non‐normality, where instead of imputing regression estimates, “real” observed values from similar cases are imputed. Methods were also compared by means of a simulated dataset. The simulation showed that the Bayesian approach yielded the most unbiased estimates for imputation. The finding of no increase in consumption levels despite a higher availability remained unaltered. Copyright © 2011 John Wiley & Sons, Ltd.
Assessing the performance of the short screening scale for post‐traumatic stress disorder in a large nationally‐representative survey
Authors: Bohnert Kipling M. , Breslau Naomi
Published: May 2011

The performance of the short screening scale for the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM‐IV) post‐traumatic stress disorder (PTSD), has not been assessed in an independent general population sample, although it has been used in epidemiological as well as clinical research. In this report we evaluate the short screening scale in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a population‐based survey of US household and group quarter residents. DSM‐IV PTSD was assessed via symptom questions in the Alcohol Use Disorder and Associated Disabilities Interview Schedule‐DSM‐IV (AUDADIS‐IV) version. Sensitivity, specificity, positive and negative predictive value, and percent correctly classified were calculated, using the interview‐based diagnosis as the standard. Replicating findings from the initial report, a score of four or more on the short screening scale identifies cases of PTSD with sensitivity of 78%, specificity of 97%, positive predictive value of 75%, and negative predictive value of 98%. The percentage of correctly classified respondents was 96%. The findings support the utility of the seven‐item scale for screening PTSD in clinical and general population samples. Copyright © 2011 John Wiley & Sons, Ltd.
Computerized home video detection for motherese may help to study impaired interaction between infants who become autistic and their parents
Authors: Mahdhaoui Ammar , Chetouani Mohamed , Cassel Raquel S. , Saint‐Georges Catherine , Parlato Erika , Laznik Marie Christine , Apicella Fabio , Muratori Filippo , Maestro Sandra , Cohen David
Published: May 2011

Autism is a well‐defined clinical syndrome after the second year of life, but information on autism in the first two years of life is still lacking. The study of home videos has described children with autism during the first year of life as not displaying the rigid pattern typical of later symptoms. Therefore, developmental/environmental factors are claimed in addition to genetic/biological ones to explain the onset of autism during maturation. Here we describe (1) a developmental hypothesis focusing on the possible implication of motherese impoverishment during the course of parent–infant interactions as a possible co‐factor; (2) the methodological approach we used to develop a computerized algorithm to detect motherese in home videos; (3) the best configuration performance of the detector in extracting motherese from home video sequences (accuracy = 82% on speaker‐independent versus 87.5% on speaker‐dependent) that we should use to test this hypothesis. Copyright © 2011 John Wiley & Sons, Ltd.
Contributions of chemical exchange to T1ρ dispersion in a tissue model
Authors: Cobb Jared G. , Xie Jingping , Gore John C.
Published: May 2011

Variations in T1ρ with locking‐field strength (T1ρ dispersion) may be used to estimate proton exchange rates. We developed a novel approach utilizing the second derivative of the dispersion curve to measure exchange in a model system of cross‐linked polyacrylamide gels. These gels were varied in relative composition of comonomers, increasing stiffness, and in pH, modifying exchange rates. Magnetic resonance images were recorded with a spin‐locking sequence as described by Sepponen et al. These measurements were fit to a mono‐exponential decay function yielding values for T1ρ at each locking‐field measured. These values were then fit to a model by Chopra et al. for estimating exchange rates. For low stiffness gels, the calculated exchange values increased by a factor of 4 as pH increased, consistent with chemical exchange being the dominant contributor to T1ρ dispersion. Interestingly, calculated chemical exchange rates also increased with stiffness, likely due to modified side‐chain exchange kinetics as the composition varied. This article demonstrates a new method to assess the structural and chemical effects on T1ρ relaxation dispersion with a suitable model. These phenomena may be exploited in an imaging context to emphasize the presence of nuclei of specific exchange rates, rather than chemical shifts. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Calibration and validation of TRUST MRI for the estimation of cerebral blood oxygenation
Authors: Lu Hanzhang , Xu Feng , Grgac Ksenija , Liu Peiying , Qin Qin , van Zijl Peter
Published: May 2011

Recently, a T2‐Relaxation‐Under‐Spin‐Tagging (TRUST) MRI technique was developed to quantitatively estimate blood oxygen saturation fraction (Y) via the measurement of pure blood T2. This technique has shown promise for normalization of fMRI signals, for the assessment of oxygen metabolism, and in studies of cognitive aging and multiple sclerosis. However, a human validation study has not been conducted. In addition, the calibration curve used to convert blood T2 to Y has not accounted for the effects of hematocrit (Hct). In this study, we first conducted experiments on blood samples under physiologic conditions, and the Carr‐Purcell‐Meiboom‐Gill T2 was determined for a range of Y and Hct values. The data were fitted to a two‐compartment exchange model to allow the characterization of a three‐dimensional plot that can serve to calibrate the in vivo data. Next, in a validation study in humans, we showed that arterial Y estimated using TRUST MRI was 0.837 ± 0.036 (N=7) during the inhalation of 14% O2, which was in excellent agreement with the gold‐standard Y values of 0.840 ± 0.036 based on Pulse‐Oximetry. These data suggest that the availability of this calibration plot should enhance the applicability of T2‐Relaxation‐Under‐Spin‐Tagging MRI for noninvasive assessment of cerebral blood oxygenation. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Analysis of complex cardiovascular flow with three‐component acceleration‐encoded MRI
Authors: Barker Alex J. , Staehle Felix , Bock Jelena , Jung Bernd A. , Markl Michael
Published: May 2011

Functional information regarding cardiac performance, pressure gradients, and local flow derangement are available from blood acceleration fields. Thus, this study examines a 2D and 3D phase contrast sequence optimized to efficiently encode three‐directional, time‐resolved acceleration in vitro and in vivo. Stenosis phantom acceleration measurements were compared to acceleration derived from standard velocity encoded phase contrast‐magnetic resonance imaging (i.e., “velocity‐derived acceleration”). For in vivo analysis, three‐directional 2D acceleration maps were compared to velocity‐derived acceleration using regions proximal and distal to the aortic valve in six healthy volunteers at 1.5 and 3.0 T (voxel size = 1.4 × 2.1 × 8 mm, temporal resolution = 16–20 ms). In addition, a 4D acceleration sequence was evaluated for feasibility in a healthy volunteer and postrepair biscuspid aortic valve patient with an ascending aortic aneurysm. The phantom magnetic resonance acceleration measurements were more accurate (nonturbulent root mean square error = 2.2 vs. 5.1 m/s2 for phase contrast‐magnetic resonance imaging) and 10 times less noisy (nonturbulent σ = 0.9 vs. 13.6 m/s2 for phase contrast‐magnetic resonance imaging) than velocity‐derived acceleration. Acceleration mapping of the left ventricular outflow tract and aortic arch exhibited signal voids colocated with complex flow events such as vortex formation and high order motion. 4D acceleration data, visualized in combination with the velocity data, may provide new insight into complex flow phenomena. Magn Reson Med 67:50–61, 2012. © 2011 Wiley Periodicals, Inc.