bluuebunny/crossref_metadata_2025 huggingface dataset:
Exclusion of elective nodal irradiation is associated with minimal elective nodal failure in non-small cell lung cancer
Authors: Sulman Erik P , Komaki Ritsuko , Klopp Ann H , Cox James D , Chang Joe Y
Published: January 2009

Background

Controversy still exists regarding the long-term outcome of patients whose uninvolved lymph node stations are not prophylactically irradiated for non-small cell lung cancer (NSCLC) treated with definitive radiotherapy. To determine the frequency of elective nodal failure (ENF) and in-field failure (IFF), we examined a large cohort of patients with NSCLC staged with positron emission tomography (PET)/computed tomography (CT) and treated with 3-dimensional conformal radiotherapy (3D-CRT) that excluded uninvolved lymph node stations.

Methods

We retrospectively reviewed the records of 115 patients with non-small cell lung cancer treated at our institution with definitive radiation therapy with or without concurrent chemotherapy (CHT). All patients were treated with 3D-CRT, including nodal regions determined by CT or PET to be disease involved. Concurrent platinum-based CHT was administered for locally advanced disease. Patients were analyzed in follow-up for survival, local regional recurrence, and distant metastases (DM).

Results

The median follow-up time was 18 months (3 to 44 months) among all patients and 27 months (6 to 44 months) among survivors. The median overall survival, 2-year actuarial overall survival and disease-free survival were 19 months, 38%, and 28%, respectively. The majority of patients died from DM, the overall rate of which was 36%. Of the 31 patients with local regional failure, 26 (22.6%) had IFF, 5 (4.3%) had ENF and 2 (1.7%) had isolated ENF. For 88 patients with stage IIIA/B, the frequencies of IFF, any ENF, isolated ENF, and DM were 23 (26%), 3 (9%), 1 (1.1%) and 36 (40.9%), respectively. The comparable rates for the 22 patients with early stage node-negative disease (stage IA/IB) were 3 (13.6%), 1(4.5%), 0 (0%), and 5 (22.7%), respectively.

Conclusion

We observed only a 4.3% recurrence of any ENF and a 1.7% recurrence of isolated ENF in patients with NSCLC treated with definitive 3D-CRT without prophylactic irradiation of uninvolved lymph node stations. Thus, distant metastasis and IFF remain the primary causes of treatment failure and cancer death in such patients, suggesting little value of ENI in this cohort.
Successful renal re-transplantation in the presence of pre-existing anti-DQ5 antibodies when there was zero mismatch at class I human leukocyte antigen A, B, & C: a case report
Authors: Hartono John , Lavingia Bhavna , Stastny Peter , Senitko Martin , Vazquez Miguel , Arenas Juan , Lu Christopher
Published: January 2009

Introduction

Hyperacute rejection may be prevented by avoiding the transplantation of kidneys into patients with pre-existing anti-donor Class I human leukocyte antigen antibodies. However, the role of anti-donor-Class II-human leukocyte antigen-DQ antibodies is not established. The question is ever more relevant as more sensitive cross-matching techniques detect many additional antibodies during the final crossmatch. We now report successful renal transplantation of a patient who had pre-existing antibodies against his donor's human leukocyte antigen-DQ5.

Case presentation

Our patient, a Caucasian man, was 34 years of age when he received his first deceased donor renal transplant. After 8 years, his first transplant failed from chronic allograft dysfunction and an earlier bout of Banff 1A cellular rejection. The second deceased donor kidney transplant was initially allocated to the patient due to a 0 out of 6 mismatch. The B cell crossmatch was mildly positive, while the T Cell crossmatch was negative. Subsequent assays showed that the patient had preformed antibodies for human leukocyte antigen DQ5 against his second donor. Despite having preformed antibodies against the donor, the patient continues to have excellent allograft function two years after his second renal transplant.

Conclusion

The presence of pre-existing antibodies against human leukocyte antigen DQ5 does not preclude transplantation. The relevance of having other antibodies against class II human leukocyte antigens prior to transplantation remains to be studied.
Enzymatic corn wet milling: engineering process and cost model
Authors: Ramírez Edna C , Johnston David B , McAloon Andrew J , Singh Vijay
Published: January 2009

Background

Enzymatic corn wet milling (E-milling) is a process derived from conventional wet milling for the recovery and purification of starch and co-products using proteases to eliminate the need for sulfites and decrease the steeping time. In 2006, the total starch production in USA by conventional wet milling equaled 23 billion kilograms, including modified starches and starches used for sweeteners and ethanol production [1]. Process engineering and cost models for an E-milling process have been developed for a processing plant with a capacity of 2.54 million kg of corn per day (100,000 bu/day). These models are based on the previously published models for a traditional wet milling plant with the same capacity. The E-milling process includes grain cleaning, pretreatment, enzymatic treatment, germ separation and recovery, fiber separation and recovery, gluten separation and recovery and starch separation. Information for the development of the conventional models was obtained from a variety of technical sources including commercial wet milling companies, industry experts and equipment suppliers. Additional information for the present models was obtained from our own experience with the development of the E-milling process and trials in the laboratory and at the pilot plant scale. The models were developed using process and cost simulation software (SuperPro Designer®) and include processing information such as composition and flow rates of the various process streams, descriptions of the various unit operations and detailed breakdowns of the operating and capital cost of the facility.

Results

Based on the information from the model, we can estimate the cost of production per kilogram of starch using the input prices for corn, enzyme and other wet milling co-products. The work presented here describes the E-milling process and compares the process, the operation and costs with the conventional process.

Conclusion

The E-milling process was found to be cost competitive with the conventional process during periods of high corn feedstock costs since the enzymatic process enhances the yields of the products in a corn wet milling process. This model is available upon request from the authors for educational, research and non-commercial uses.
Preoperative detection of insulinomas: two case reports
Authors: Ozkaya Mesut , Yuzbasioglu Mehmet Fatih , Koruk Irfan , Cakal Erman , Sahin Mustafa , Cakal Basak
Published: January 2009

Background

Insulinoma is the most common endocrine tumor of the pancreas. Accurate preoperative detection and localization of insulinomas is essential for the appropriate selection of candidates for surgery. We present two cases with benign pancreatic insulinoma.

Case presentation

Preoperative evaluation for patients with suspected insulinomas has been controversial. Endoscopic ultrasonography (EUS) has a sensitivity of 95% in well skilled operators and well tolerated preoperative imaging method.

Conclusion

We have detected the insulinomas with EUS before surgery in our patients but other imaging modalities did not help us for localization of them. Patients have been asymptomatic postoperatively with no hypoglycemia on repeat fasting. We reviewed here the different modalities for preoperative localization of insulinoma.
Human antimicrobial protein hCAP18/LL-37 promotes a metastatic phenotype in breast cancer
Authors: Weber Günther , Chamorro Clara Ibel , Granath Fredrik , Liljegren Annelie , Zreika Sami , Saidak Zuzana , Sandstedt Bengt , Rotstein Samuel , Mentaverri Romuald , Sánchez Fabio , Pivarcsi Andor , Ståhle Mona
Published: January 2009

Introduction

Human cathelicidin antimicrobial protein, hCAP18, and its C-terminal peptide LL-37 is a multifunctional protein. In addition to being important in antimicrobial defense, it induces chemotaxis, stimulates angiogenesis and promotes tissue repair. We previously showed that human breast cancer cells express high amounts of hCAP18, and hypothesised that hCAP18/LL-37 may be involved in tumour progression.

Methods

hCAP18 mRNA was quantified in 109 primary breast cancers and compared with clinical findings and ERBB2 mRNA expression. Effects of exogenous LL-37 and transgenic overexpression of hCAP18 on ErbB2 signalling were investigated by immunoblotting using extracts from breast cancer cell lines ZR75-1 and derivatives of MCF7. We further analysed the impact of hCAP18/LL-37 on the morphology of breast cancer cells grown in soft agar, on cell migration and on tumour development in severe combined immunodeficiency (SCID) mice.

Results

The expression of hCAP18 correlated closely with that of ERBB2 and with the presence of lymph node metastases in oestrogen receptor-positive tumours. hCAP18/LL-37 amplified Heregulin-induced mitogen-activated protein kinase (MAPK) signalling through ErbB2, identifying a functional association between hCAP18/LL-37 and ErbB2 in breast cancer. Treatment with LL-37 peptide significantly stimulated the migration of breast cancer cells and their colonies acquired a dispersed morphology indicative of increased metastatic potential. A truncated version of LL-37 competitively inhibited LL-37 induced MAPK phosphorylation and significantly reduced the number of altered cancer cell colonies induced by LL-37 as well as suppressed their migration. Transgenic overexpression of hCAP18 in a low malignant breast cancer cell line promoted the development of metastases in SCID mice, and analysis of hCAP18 transgenic tumours showed enhanced activation of MAPK signalling.

Conclusions

Our results provide evidence that hCAP18/LL-37 contributes to breast cancer metastasis.
Universal features in the genome-level evolution of protein domains
Authors: Cosentino Lagomarsino Marco , Sellerio Alessandro L , Heijning Philip D , Bassetti Bruno
Published: January 2009

Background

Protein domains can be used to study proteome evolution at a coarse scale. In particular, they are found on genomes with notable statistical distributions. It is known that the distribution of domains with a given topology follows a power law. We focus on a further aspect: these distributions, and the number of distinct topologies, follow collective trends, or scaling laws, depending on the total number of domains only, and not on genome-specific features.

Results

We present a stochastic duplication/innovation model, in the class of the so-called 'Chinese restaurant processes', that explains this observation with two universal parameters, representing a minimal number of domains and the relative weight of innovation to duplication. Furthermore, we study a model variant where new topologies are related to occurrence in genomic data, accounting for fold specificity.

Conclusions

Both models have general quantitative agreement with data from hundreds of genomes, which indicates that the domains of a genome are built with a combination of specificity and robust self-organizing phenomena. The latter are related to the basic evolutionary 'moves' of duplication and innovation, and give rise to the observed scaling laws, a priori of the specific evolutionary history of a genome. We interpret this as the concurrent effect of neutral and selective drives, which increase duplication and decrease innovation in larger and more complex genomes. The validity of our model would imply that the empirical observation of a small number of folds in nature may be a consequence of their evolution.
Cognitive–behavioural therapyv. social activity therapy for people with psychosis and a history of violence: randomised controlled trial
Authors: Haddock Gillian , Barrowclough Christine , Shaw Jennifer J. , Dunn Graham , Novaco Raymond W. , Tarrier Nicholas
Published: January 2009

Background

Aggression and violence are serious problems in schizophrenia. Cognitive–behavioural therapy (CBT) has been shown to be an effective treatment for psychosis although there have been no studies to date evaluating the impact of CBT for people with psychosis and a history of violence.

Aims

To investigate the effectiveness of CBT on violence, anger, psychosis and risk outcomes with people who had a diagnosis of schizophrenia and a history of violence.

Method

This was a single-blind randomised controlled trial of CBTv. social activity therapy (SAT) with a primary outcome of violence and secondary outcomes of anger, symptoms, functioning and risk. Outcomes were evaluated by masked assessors at 6 and 12 months (trial registration: NRR NO50087441).

Results

Significant benefits were shown for CBT compared with control over the intervention and follow-up period on violence, delusions and risk management.

Conclusions

Cognitive–behavioural therapy targeted at psychosis and anger may be an effective treatment for reducing the occurrence of violence and further investigation of its benefits is warranted.
Suicides in female prisoners in England and Wales, 1978–2004
Authors: Fazel Seena , Benning Ram
Published: January 2009

We calculated, in narrow age bands, suicide rates for female prisoners compared with the general population between 1978 and 2004. The standardised mortality ratio (SMR) for suicide was 20.7 (95% CI 16.7–25.7), with a higher excess in younger women (525 years, SMR=40 (95% CI 29–57); 525 years, SMR=20 (95% CI 15–26)). There was a trend over time for SMRs to have increased, supporting the need for recent national initiatives for suicide prevention in prisoners.
Adolescent-onset anorexia nervosa: 18-year outcome
Authors: Wentz Elisabet , Gillberg I. Carina , Anckarsäter Henrik , Gillberg Christopher , Råstam Maria
Published: January 2009

Background

The long-term outcome of anorexia nervosa is insufficiently researched.

Aims

To study prospectively the long-term outcome and prognostic factors in a representative sample of people with teenage-onset anorexia nervosa.

Method

Fifty-one people with anorexia nervosa, recruited by community screening and with a mean age at onset of 14 years were compared with 51 matched comparison individuals at a mean age of 32 years (18 years after disorder onset). All participants had been examined at ages 16 years, 21 years and 24 years. They were interviewed for Axis I psychiatric disorders and overall outcome (Morgan–Russell assessment schedule and the Global Assessment of Functioning).

Results

There were no deaths. Twelve per cent (n=6) had a persisting eating disorder, including three with anorexia nervosa. Thirty-nine per cent of the anorexia nervosa group met the criteria for at least one psychiatric disorder. The general outcome was poor in 12%. One in four did not have paid employment owing to psychiatric problems. Poor outcome was predicted by premorbid obsessive–compulsive personality disorder, age at onset of anorexia nervosa and autistic traits.

Conclusions

The 18-year outcome of teenage-onset anorexia nervosa is favourable in respect of mortality and persisting eating disorder.
Suicide in dementia: 9-year national clinical survey in England and Wales
Authors: Purandare Nitin , Voshaar Richard C. Oude , Rodway Cathryn , Bickley Harriet , Burns Alistair , Kapur Nav
Published: January 2009

Background

Knowledge of suicide in people with dementia is limited to small case series.

Aims

To describe behavioural, clinical and care characteristics of people with dementia who died by suicide.

Method

All dementia cases (n=118) from a 9-year national clinical survey of suicides in England and Wales (n=11 512) were compared with age- and gender-matched non-dementia cases (control group) (n=492) by conditional logistic regression.

Results

The most common method of suicide in patients with dementia was self-poisoning, followed by drowning and hanging, the latter being less frequent than in controls. In contrast to controls, significantly fewer suicides occurred within 1 year of diagnosis in patients with dementia. Patients with dementia were also less likely to have a history of self-harm, psychiatric symptoms and previous psychiatric admissions.

Conclusions

Known indicators of suicide risk are found less frequently in dementia suicide cases than non-dementia suicide cases. Further research should clarify whether suicide in dementia is a response to worsening dementia or an under-appreciation of psychiatric symptoms by clinicians.

Declaration on interest

None.

Funding detailed in Acknowledgements.
Comparative epidemiology of chronic fatigue syndrome in Brazilian and British primary care: prevalence and recognition
Authors: Cho Hyong Jin , Menezes Paulo Rossi , Hotopf Matthew , Bhugra Dinesh , Wessely Simon
Published: January 2009

Background

Although fatigue is a ubiquitous symptom across countries, clinical descriptions of chronic fatigue syndrome have arisen from a limited number of high-income countries. This might reflect differences in true prevalence or clinical recognition influenced by sociocultural factors.

Aims

To compare the prevalence, physician recognition and diagnosis of chronic fatigue syndrome in London and São Paulo.

Method

Primary care patients in London (n=2459) and São Paulo (n=3914) were surveyed for the prevalence of chronic fatigue syndrome. Medical records were reviewed for the physician recognition and diagnosis.

Results

The prevalence of chronic fatigue syndrome according to Centers for Disease Control 1994 criteria was comparable in Britain and Brazil: 2.1%v. 1.6% (P=0.20). Medical records review identified 11 diagnosed cases of chronic fatigue syndrome in Britain, but none in Brazil (P<0.001).

Conclusions

The primary care prevalence of chronic fatigue syndrome was similar in two culturally and economically distinct nations. However, doctors are unlikely to recognise and label chronic fatigue syndrome as a discrete disorder in Brazil. The recognition of this illness rather than the illness itself may be culturally induced.
Dementia screening in acute medical and geriatric hospital admissions
Authors: Gordon Alison , Hu Hilda , Byrne Anthony , Stott David J.
Published: January 2009

Aims and Method

We studied a representative cohort of 161 patients over 65 years of age, admitted non-electively to medical and geriatric wards of a large teaching hospital. Assessment for dementia was made using DSM–IV criteria. Psychiatric records were then examined, masked, to determine the involvement of psychogeriatric services.

Results

There were 111 possible cases of dementia (69%), of which 30 (27%) had prior local psychogeriatric case notes; in 22 cases (20%) the patient had a prior psychiatric diagnosis of dementia. of 161 patients, 19 (12%) were seen by psychogeriatric services during their admission, of whom 12 (7%) were already known to psychiatric services. Dementia was diagnosed in 17 (complicated by delirium in 2), depression in 1 and hypomania in 1. Many patients with a possible diagnosis of dementia had no psychiatric assessment.

Clinical Implications

Psychogeriatric assessment was performed on a minority of older people admitted to medical care. This population may include older people with undiagnosed dementia and unmet psychiatric care needs.
Guidelines on antipsychotics for dementia: are we losing our minds?
Authors: Haw Camilla , Yorston Graeme , Stubbs Jean
Published: January 2009

Aims and Method

The National Institute for Health and Clinical Excellence (NICE) and the Royal College of Psychiatrists have each issued guidance on the use of antipsychotics for behavioural and psychiatric symptoms of dementia (BPSD). We sent all old age psychiatrists an anonymous questionnaire asking for their opinions on these documents and for details of their use of antipsychotics for BPSD.

Results

The response rate was 202 out of 648 (31.2%). the two documents, though similar in content provoked very different responses, with the College guidance being much more favourably received. All respondents prescribed antipsychotics for BPSD, most commonly quetiapine.

Clinical Implications

When prescribing antipsychotics for behavioural and psychiatric symptoms of dementia, psychiatrists should take both NICE and College guidelines into account and use their clinical judgement.
Psychiatric symptoms in Ground Zero ironworkers in the aftermath of 9/11: prevalence and predictors
Authors: Katz Craig L. , Levin Stephen , Herbert Robin , Munro Simon , Pandya Anand , Smith Rebecca
Published: January 2009

Aims and Method

To establish the prevalence of, and risk factors for, psychiatric symptoms in Ground Zero ironworkers. Questionnaires commonly used to screen for psychiatric symptoms were completed by 124 workers.

Results

We have established the prevalence of screening positive for symptoms of post-traumatic stress disorder, panic attacks, generalised anxiety, depression and alcohol misuse. Among the risk factors were alcohol misuse, injury to or death of a family member, friend or co-worker at Ground Zero and one or more adverse life events since 9/11.

Clinical Implications

Ironworkers at Ground Zero tend to have significant psychiatric symptoms likely to be associated with the traumatic experience of working there during the clean-up operation. Risk factors for psychiatric symptoms were established.
Service user organisations: an untapped teaching resource
Authors: diMambro Ben J. , Doody Gillian A.
Published: January 2009

Aims and Method

To evaluate the introduction of service user-led teaching on experiences of psychiatric services and interview style into the educational programme of trainee psychiatrists. A ten-session programme was devised and delivered in conjunction with a local service user organisation. Twelve trainees underwent the training programme. Evaluation was undertaken through analysis of the feedback forms completed by the trainees.

Results

No significant difference was found between service user-led and psychiatrist-led sessions in content, relevance or presentation.

Clinical Implications

The study demonstrated that service user-led teaching can be integrated into a trainee's education programme without reducing the perceived quality or relevance of their education.
Human Uterine Smooth Muscle and Leiomyoma Cells Differ in Their Rapid 17β-Estradiol Signaling: Implications for Proliferation
Authors: Nierth-Simpson Erica N. , Martin Melvenia M. , Chiang Tung-Chin , Melnik Lilia I. , Rhodes Lyndsay V. , Muir Shannon E. , Burow Matthew E. , McLachlan John A.
Published: January 2009

Uterine leiomyomas, benign uterine smooth muscle tumors that affect 30% of reproductive-aged women, are a significant health concern. The initiation event for these tumors is unclear, but 17β-estradiol (E2) is an established promoter of leiomyoma growth. E2 not only alters transcription of E2-regulated genes but also can rapidly activate signaling pathways. The aim of our study is to investigate the role of rapid E2-activated cytoplasmic signaling events in the promotion of leiomyomas. Western blot analysis revealed that E2 rapidly increases levels of phosphorylated protein kinase Cα (PKCα) in both immortalized uterine smooth muscle (UtSM) and leiomyoma (UtLM) cell lines, but increases levels of phosphorylated ERK1/2 only in UtLM cells. Our studies demonstrate a paradoxical effect of molecular and pharmacological inhibition of PKCα on ERK1/2 activation and cellular proliferation in UtLM and UtSM cells. PKCα inhibition decreases levels of phosphorylated ERK1/2 and proliferation in UtLM cells but raises these levels in UtSM cells. cAMP-PKA signaling is rapidly activated only in UtSM cells with E2 and inhibits ERK1/2 activation and proliferation. We therefore propose a model whereby E2’s rapid activation of PKCα and cAMP-PKA signaling plays a central role in the maintenance of a low proliferative index in normal uterine smooth muscle via its inhibition of the MAPK cascade and these pathways are altered in leiomyomas to promote MAPK activation and proliferation. These studies demonstrate that rapid E2-signaling pathways contribute to the promotion of leiomyomas.
The Role of mPer2 Clock Gene in Glucocorticoid and Feeding Rhythms
Authors: Yang Shutong , Liu Aiyi , Weidenhammer Adam , Cooksey Robert C. , McClain Donald , Kim Myung K. , Aguilera Greti , Abel E. Dale , Chung Jay H.
Published: January 2009

The circadian clock synchronizes the activity level of an organism to the light-dark cycle of the environment. Energy intake, as well as energy metabolism, also has a diurnal rhythm. Although the role of the clock genes in the sleep-wake cycle is well characterized, their role in the generation of the metabolic rhythms is poorly understood. Here, we use mice deficient in the clock protein mPer2 to study how the circadian clock regulates two critical metabolic rhythms: glucocorticoid and food intake rhythms. Our findings indicate that mPer2−/− mice do not have a glucocorticoid rhythm even though the corticosterone response to hypoglycemia, ACTH, and restraint stress is intact. In addition, the diurnal feeding rhythm is absent in mPer2−/− mice. On high-fat diet, they eat as much during the light period as they do during the dark period and develop significant obesity. The diurnal rhythm of neuroendocrine peptide αMSH, a major effector of appetite control, is disrupted in the hypothalamus of mPer2−/− mice even though the diurnal rhythm of ACTH, the αMSH precursor, is intact. Peripheral injection of αMSH, which has been shown to enter the brain, restored the feeding rhythm and induced weight loss in mPer2−/− mice. These findings emphasize the requirement of mPer2 in appetite control during the inactive period and the potential role of peripherally administered αMSH in restoring night-day eating pattern in individuals with circadian eating disorders such as night-eating syndrome, which is also associated with obesity.
Postreceptoral Adipocyte Insulin Resistance Induced by Nelfinavir Is Caused by Insensitivity of PKB/Akt to Phosphatidylinositol-3,4,5-Trisphosphate
Authors: Kachko Ilana , Maissel Adva , Mazor Livnat , Ben-Romano Ronit , Watson Robert T. , Hou June C. , Pessin Jeffrey E. , Bashan Nava , Rudich Assaf
Published: January 2009

Adipocyte insulin resistance can be caused by proximal insulin signaling defects but also from postreceptor mechanisms, which in large are poorly characterized. Adipocytes exposed for 18 h to the HIV protease inhibitor nelfinavir manifest insulin resistance characterized by normal insulin-stimulated tyrosine phosphorylation of the insulin receptor and insulin receptor substrate proteins, preserved in vitro phosphatidylinositol 3-kinase (PI 3-kinase) assay activity but impaired activation of PKB/Akt and stimulation of glucose uptake. Here we aimed to assess whether impaired PKB/Akt activation is indeed rate limiting for insulin signaling propagation in response to nelfinavir and the mechanism for defective PKB/Akt activation. Nelfinavir treatment of 3T3-L1 adipocytes impaired the insulin-stimulated translocation and membrane fusion of myc-glucose transporter (GLUT)-4-green fluorescent protein (GFP) reporter. Phosphorylation of PKB/Akt substrates including glycogen synthase kinase-3 and AS160 decreased in response to nelfinavir, and this remained true, even in cells with forced generation of phosphatidylinositol-3,4,5-trisphohphate (PIP3) by a membrane-targeted active PI 3-kinase, confirming that impaired PKB/Akt activation was rate limiting for insulin signal propagation. Cells expressing a GFP-tagged pleckstrin homology domain of general receptors for phosphoinositides 1, which binds PIP3, revealed intact PIP3-mediated plasma membrane translocation of this reporter in nelfinavir-treated cells. However, expression of a membrane-targeted catalytic subunit of PI 3-kinase failed to induce myc-GLUT4-GFP translocation in the absence of insulin, as it did in control cells. Conversely, a membrane-targeted and constitutively active PKB/Akt mutant was normally phosphorylated on S473 and T308, confirming intact PKB/Akt kinases activity, and induced myc-GLUT4-GFP translocation. Collectively, nelfinavir uncovers a postreceptor mechanism for insulin resistance, caused by interference with the sensing of PIP3 by PKB/Akt, leading to impaired GLUT4 translocation and membrane fusion.
Peroxisome-Proliferator Receptor γ Represses Hepatic Sex Hormone-Binding Globulin Expression
Authors: Selva David M. , Hammond Geoffrey L.
Published: January 2009

Plasma SHBG production by the liver is influenced by its metabolic state, and hepatocyte nuclear factor-4α regulates SHBG expression in response to changes in lipogenesis. Peroxisome-proliferator receptors (PPARs) also regulate glucose homeostasis and fatty acid metabolism. The human SHBG promoter contains a PPAR-response element (PPAR-RE), and plasma SHBG levels increase in polycystic ovarian syndrome patients treated with the PPARγ agonist, rosiglitazone. In addition, plasma SHBG levels are associated with a genetic polymorphism in the PPARγ-2 coding sequence that alters its transcriptional activity. Therefore, we set out to determine whether PPARγ influences hepatic production of SHBG by using human HepG2 hepatoblastoma cells as an in vitro model. Surprisingly, treatment of HepG2 cells with rosiglitazone reduced SHBG production and SHBG promoter activity (as assessed in a luciferase reporter gene assay) by 20–25%, whereas the PPARγ antagonist, GW9662, increased both by 2- to 3-fold. The effects of PPARγ agonists and antagonists on SHBG promoter activity were substantially diminished when the PPAR-RE in the SHBG promoter was mutated. A PPARγ small interfering RNA also increased SHBG production by HepG2 cells as well as SHBG promoter activity, and the latter was accentuated by cotreatment with GW9662. Importantly, overexpression of a PPARγ-2 Pro12 variant in HepG2 cells was more effective at reducing SHBG promoter activity, when compared with PPARγ-2 Ala12, consistent with its superior PPAR-RE binding activity. We conclude that PPARγ represses human SHBG expression in liver cells, and that differences in PPARγ levels and activity contribute directly to variations in plasma SHBG levels.
Stathmin, a Microtubule Regulatory Protein, Is Associated with Hypoxia-Inducible Factor-1α Levels in Human Endometrial and Endothelial Cells
Authors: Yoshie Mikihiro , Miyajima Eri , Kyo Satoru , Tamura Kazuhiro
Published: January 2009

Local hypoxia that occurs during menstruation triggers angiogenesis that is crucial for cyclical remodeling of the endometrium during the menstrual cycle. Hypoxia is thought to be important for the expression of vascular endothelial growth factor (VEGF) via its transcriptional factor, hypoxia inducible factor (HIF)-1α, in the endometrium. The activation of the phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway may modulate HIF-1α protein levels. Stathmin, a microtubule regulatory protein, was expressed in the stroma, glandular epithelium, and vascular endothelium in human endometrium. In this study, we examined a possible role of stathmin in hypoxia-induced HIF-1α and VEGF expression in primary isolated and immortalized human endometrial stromal cells, glandular epithelial cells, and human umbilical venous endothelial cells (HUVEC). Knocking down stathmin expression using small interfering RNA caused microtubule stabilization and inhibited hypoxia-induced VEGF mRNA expression via the reduction of HIF-1α protein levels in endometrial cells and HUVEC. Treatment of the cells with a PI3K inhibitor, wortmannin, inhibited the expression of VEGF mRNA and the accumulation of HIF-1α protein. Silencing of stathmin expression repressed the activation (phosphorylation) of Akt in endometrial cells and HUVEC. These results suggest that endometrial stathmin is linked to HIF-1α protein accumulation and VEGF expression through the PI3K/Akt signaling pathway and may be involved in regeneration of the endometrium during the menstrual cycle in human uterine cells.
Chronic Endothelium-Dependent Regulation of Arterial Blood Pressure by Atrial Natriuretic Peptide: Role of Nitric Oxide and Endothelin-1
Authors: Sabrane Karim , Kruse Markus-N. , Gazinski Alexandra , Kuhn Michaela
Published: January 2009

Atrial natriuretic peptide (ANP), via its guanylyl cyclase (GC)-A receptor, plays a key role in the regulation of arterial blood pressure (ABP) and volume. Endothelial-restricted deletion of GC-A in mice [endothelial cell (EC) GC-A knockout (KO)] resulted in hypervolemic hypertension, demonstrating that the endothelium participates in the hypotensive and hypovolemic actions of ANP. Published studies showed that ANP modulates the release of the vasoactive factors nitric oxide (NO) and endothelin-1 (ET-1) from cultured endothelia. Based on these observations, we examined the role of these endothelial factors in ANP-dependent vasodilatation (studied in isolated arteries) and chronic regulation of ABP (measured in awake mice by tail-cuff plethysmography). ANP induced concentration-dependent vasorelaxations of aortic, carotid, and pulmonary arteries. These responses were not different between control and EC GC-A KO mice, and were significantly enhanced after inhibition of NO synthase [by N(G)-nitro-l-arginine-methyl ester]. Intravenous administration of N(G)-nitro-l-arginine-methyl ester to conscious mice significantly increased ABP. The extent of these hypertensive reactions was similar in EC GC-A KO mice and control littermates (increases in systolic blood pressure by ∼25 mm Hg). Conversely, antagonism of ET-1/endothelin-A receptors with BQ-123 reduced ABP significantly and comparably in both genotypes (by ∼11 mm Hg). Finally, the vascular and tissue expression levels of components of the NO system and of immunoreactive ET-1 were not different in control and EC GC-A KO mice. We conclude that the endothelium, but not modulation of endothelial NO or ET-1, participates in the chronic regulation of ABP by ANP.
Reduced Energy Expenditure and Increased Inflammation Are Early Events in the Development of Ovariectomy-Induced Obesity
Authors: Rogers Nicole H. , Perfield James W. , Strissel Katherine J. , Obin Martin S. , Greenberg Andrew S.
Published: January 2009

Menopause, an age-related loss of ovarian hormone production, promotes increased adiposity and insulin resistance. However, the diet-independent mechanism by which loss of ovarian function promotes increased adipose tissue mass and associated metabolic pathologies remains unclear. To address this question, we monitored food intake and weight gain of ovariectomized (OVX) mice and sham OVX (SHM) mice for 12 wk. Although food intake was similar, OVX mice gained 25% more weight than SHM mice. Moreover, the OVX mice accumulated 4.7- and 4.4-fold more perigonadal and inguinal adipose tissue by weight, respectively, with 4.4-fold (perigonadal, P < 0.001) and 5.3-fold (inguinal, P < 0.01) larger adipocytes and no change in adipocyte cell number. OVX-induced adiposity was coincident with an 18% decrease in metabolic rate during the dark phase (P = 0.001) as well as an 11% decrease during the light phase (P = 0.03). In addition, ambulatory activity levels of OVX mice were decreased only during the dark phase (40%, P = 0.008). OVX mice displayed evidence of immune infiltration and inflammation in adipose tissue, because perigonadal and inguinal adipose depots from OVX mice had increased expression of TNFα, iNOS, CD11c, and other hallmarks of adipose tissue inflammation. In contrast, expression of the T cell marker CD3 (3.5-fold, P = 0.03) and Th1 cytokine interferon-γ (IFNγ) (2.6-fold, P = 0.02) were elevated in perigonadal but not sc fat. Finally, histology revealed OVX-specific liver hepatic steatosis, coincident with increased PPARγ gene expression and downstream lipogenic gene expression. In summary, OVX in mice decreases energy expenditure, without altering energy intake, resulting in adipocyte hypertrophy, adipose tissue inflammation, and hepatic steatosis.
Pathophysiological Importance of Thyroid Hormone Transporters
Authors: Heuer Heike , Visser Theo J.
Published: January 2009

Thyroid hormone metabolism and action are largely intracellular events that require transport of iodothyronines across the plasma membrane. It has been assumed for a long time that this occurs by passive diffusion, but it has become increasingly clear that cellular uptake and efflux of thyroid hormone is mediated by transporter proteins. Recently, several active and specific thyroid hormone transporters have been identified, including monocarboxylate transporter 8 (MCT8), MCT10, and organic anion transporting polypeptide 1C1 (OATP1C1). The latter is expressed predominantly in brain capillaries and transports preferentially T4, whereas MCT8 and MCT10 are expressed in multiple tissues and are capable of transporting different iodothyronines. The pathophysiological importance of thyroid hormone transporters has been established by the demonstration of MCT8 mutations in patients with severe psychomotor retardation and elevated serum T3 levels. MCT8 appears to play an important role in the transport of thyroid hormone in the brain, which is essential for the crucial action of the hormone during brain development. It is expected that more specific thyroid hormone transporters will be discovered in the near future, which will lead to a better understanding of the tissue-specific regulation of thyroid hormone bioavailability.

Specific thyroid hormone transporters may be discovered in the near future, leading to a better understanding of the tissue-specific regulation of thyroid hormone bioavailability.
Retinoic Acid Reduces Glucocorticoid Sensitivity in C2C12 Myotubes by Decreasing 11β-Hydroxysteroid Dehydrogenase Type 1 and Glucocorticoid Receptor Activities
Authors: Aubry Evelyne M. , Odermatt Alex
Published: January 2009

Vitamin A is a nutrient with remarkable effects on adipose tissue and skeletal muscles, and plays a role in controlling energy balance. Retinoic acid (RA), the carboxylic form of vitamin A, has been associated with improved glucose tolerance and insulin sensitivity. In contrast, elevated glucocorticoids have been implicated in the development of insulin resistance and impaired glucose tolerance. Here, we investigated whether RA might counteract glucocorticoid effects in skeletal muscle cells by lowering 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1)-dependent local glucocorticoid activation and/or activation of glucocorticoid receptor (GR). We found a dose-dependent down-regulation of 11β-HSD1 mRNA expression and activity upon incubation of fully differentiated mouse C2C12 myotubes with RA. In addition, RA inhibited GR transactivation by an 11β-HSD1-independent mechanism. The presence of RA during myogenesis did not prevent myotube formation but resulted in relatively glucocorticoid-resistant myotubes, exhibiting very low 11β-HSD1 expression and GR activity. The use of selective retinoic acid receptor (RAR) and retinoid X receptor ligands provided evidence that these effects were mediated through RARγ. Importantly, short hairpin RNA against RARγ abolished the effect of RA on 11β-HSD1 and GR. In conclusion, we provide evidence for an important role of RA in the control of glucocorticoid activity during myogenesis and in myotubes. Disturbances of the nutrient and hormonal regulation of glucocorticoid action in skeletal muscles might be relevant for metabolic diseases.
Tanycyte Pyroglutamyl Peptidase II Contributes to Regulation of the Hypothalamic-Pituitary-Thyroid Axis through Glial-Axonal Associations in the Median Eminence
Authors: Sánchez Edith , Vargas Miguel Angel , Singru Praful S. , Pascual Isel , Romero Fidelia , Fekete Csaba , Charli Jean-Louis , Lechan Ronald M.
Published: January 2009

Pyroglutamyl peptidase II (PPII), a highly specific membrane-bound metallopeptidase that inactivates TRH in the extracellular space, is tightly regulated by thyroid hormone in cells of the anterior pituitary. Whether PPII has any role in the region where axons containing hypophysiotropic TRH terminate, the median eminence, is unknown. For this purpose, we analyzed the cellular localization and regulation of PPII mRNA in the mediobasal hypothalamus in adult, male rats. PPII mRNA was localized in cells lining the floor and infralateral walls of the third ventricle and coexpressed with vimentin, establishing these cells as tanycytes. PPII mRNA extended in a linear fashion from the tanycyte cell bodies in the base of the third ventricle to its cytoplasmic and end-feet processes in the external zone of the median eminence in close apposition to pro-TRH-containing axon terminals. Compared with vehicle-treated, euthyroid controls, animals made thyrotoxic by the ip administration of 10 μg l-T4 daily for 1–3 d, showed dramatically increased accumulation of silver grains in the mediobasal hypothalamus and an approximately 80% increase in enzymatic activity. PPII inhibition in mediobasal hypothalamic explants increased TRH secretion, whereas ip injection of a specific PPII inhibitor increased cold stress- and TRH-induced TSH levels in plasma. We propose that an increase in circulating thyroid hormone up-regulates PPII activity in tanycytes and enhances degradation of extracellular TRH in the median eminence through glial-axonal associations, contributing to the feedback regulation of thyroid hormone on anterior pituitary TSH secretion.
cAMP-Dependent Posttranscriptional Regulation of Steroidogenic Acute Regulatory (STAR) Protein by the Zinc Finger Protein ZFP36L1/TIS11b
Authors: Duan Haichuan , Cherradi Nadia , Feige Jean-Jacques , Jefcoate Colin
Published: January 2009

Star is expressed in steroidogenic cells as 3.5- and 1.6-kb transcripts that differ only in their 3′-untranslated regions (3′-UTR). In mouse MA10 testis and Y-1 adrenal lines, Br-cAMP preferentially stimulates 3.5-kb mRNA. ACTH is similarly selective in primary bovine adrenocortical cells. The 3.5-kb form harbors AU-rich elements (AURE) in the extended 3′-UTR, which enhance turnover. After peak stimulation of 3.5-kb mRNA, degradation is seen. Star mRNA turnover is enhanced by the zinc finger protein ZFP36L1/TIS11b, which binds to UAUUUAUU repeats in the extended 3′-UTR. TIS11b is rapidly stimulated in each cell type in parallel with Star mRNA. Cotransfection of TIS11b selectively decreases cytomegalovirus-promoted Star mRNA and luciferase-Star 3′-UTR reporters harboring the extended 3′-UTR. Direct complex formation was demonstrated between TIS11b and the extended 3′-UTR of the 3.5-kb Star. AURE mutations revealed that TIS11b-mediated destabilization required the first two UAUUUAUU motifs. HuR, which also binds AURE, did not affect Star expression. Targeted small interfering RNA knockdown of TIS11b specifically enhanced stimulation of 3.5-kb Star mRNA in bovine adrenocortical cells, MA-10, and Y-1 cells but did not affect the reversals seen after peak stimulation. Direct transfection of Star mRNA demonstrated that Br-cAMP stimulated a selective turnover of 3.5-kb mRNA independent of AURE, which may correspond to these reversal processes. Steroidogenic acute regulatory (STAR) protein induction was halved by TIS11b knockdown, concomitant with decreased cholesterol metabolism. TIS11b suppression of 3.5-kb mRNA is therefore surprisingly coupled to enhanced Star translation leading to increased cholesterol metabolism.
Agonist-Independent Interactions between β-Arrestins and Mutant Vasopressin Type II Receptors Associated with Nephrogenic Syndrome of Inappropriate Antidiuresis
Authors: Kocan Martina , See Heng B. , Sampaio Natália G. , Eidne Karin A. , Feldman Brian J. , Pfleger Kevin D. G.
Published: January 2009

Nephrogenic syndrome of inappropriate antidiuresis is a recently identified genetic disease first described in two unrelated male infants with severe symptomatic hyponatremia. Despite undetectable arginine vasopressin levels, patients have inappropriately concentrated urine resulting in hyponatremia, hypoosmolality, and natriuresis. It was found that each infant had a different mutation of the vasopressin type II receptor (V2R) at codon 137 where arginine was converted to cysteine or leucine (R137C or R137L), resulting in constitutive signaling. Interestingly, a missense mutation at the same codon, converting arginine to histidine (R137H), leads to the opposite disease phenotype with a loss of the kidney’s ability to concentrate urine resulting in nephrogenic diabetes insipidus. This mutation is associated with impaired signaling, although whether this is predominantly due to impaired trafficking to the plasma membrane, agonist-independent internalization, or G protein uncoupling is currently unclear. Using bioluminescence resonance energy transfer and confocal microscopy, we demonstrate that both V2R-R137C and V2R-R137L mutants interact with β-arrestins in an agonist-independent manner resulting in dynamin-dependent internalization. This phenotype is similar to that observed for V2R-R137H, which is intriguing considering that it is accompanied by constitutive rather than impaired signaling. Consequently, it would seem that agonist-independent internalization per se is unlikely to be the major determinant of impaired V2R-R137H signaling. Our findings indicate that the V2R-R137C and V2R-R137L mutants traffic considerably more efficiently to the plasma membrane than V2R-R137H, identifying this as a potentially important mutation-dependent difference affecting V2R function.
Do mitochondrial properties explain intraspecific variation in thermal tolerance?
Authors: Fangue Nann A. , Richards Jeffrey G. , Schulte Patricia M.
Published: January 2009

As global temperatures rise, there is a growing need to understand the physiological mechanisms that determine an organism's thermal niche. Here, we test the hypothesis that increases in mitochondrial capacity with cold acclimation and adaptation are associated with decreases in thermal tolerance using two subspecies of killifish (Fundulus heteroclitus) that differ in thermal niche. We assessed whole-organism metabolic rate, mitochondrial amount and mitochondrial function in killifish acclimated to several temperatures. Mitochondrial enzyme activities and mRNA levels were greater in fish from the northern subspecies, particularly in cold-acclimated fish,suggesting that the putatively cold-adapted northern subspecies has a greater capacity for increases in mitochondrial amount in response to cold acclimation. When tested at the fish's acclimation temperature, maximum ADP-stimulated (State III) rates of mitochondrial oxygen consumption in vitro were greater in cold-acclimated northern fish than in southern fish but did not differ between subspecies at higher acclimation temperatures. Whole-organism metabolic rate was greater in fish of the northern subspecies at all acclimation temperatures. Cold acclimation also changed the response of mitochondrial respiration to acute temperature challenge. Mitochondrial oxygen consumption was greater in cold-acclimated northern fish than in southern fish at low test temperatures, but the opposite was true at high test temperatures. These differences were reflected in whole-organism oxygen consumption. Our data indicate that the plasticity of mitochondrial function and amount differs between killifish subspecies, with the less high-temperature tolerant, and putatively cold adapted, northern subspecies having greater ability to increase mitochondrial capacity in the cold. However, there were few differences in mitochondrial properties between subspecies at warm acclimation temperatures, despite differences in both whole-organism oxygen consumption and thermal tolerance at these temperatures.