bluuebunny/crossref_metadata_2025 huggingface dataset:
Tsukushicontrols ectodermal patterning and neural crest specification inXenopus by direct regulation of BMP4 and X-delta-1 activity
Authors: Kuriyama Sei , Lupo Giuseppe , Ohta Kunimasa , Ohnuma Shin-ichi , Harris William A. , Tanaka Hideaki
Published: December 2005

In Xenopus, ectodermal patterning depends on a mediolateral gradient of BMP signaling, higher in the epidermis and lower in the neuroectoderm. Neural crest cells are specified at the border between the neural plate and the epidermis, at intermediate levels of BMP signaling. We recently described a novel secreted protein, Tsukushi (TSK),which works as a BMP antagonist during chick gastrulation. Here, we report on the Xenopus TSK gene (X-TSK), and show that it is involved in neural crest specification. X-TSK expression accumulates after gastrulation at the anterior-lateral edges of the neural plate, including the presumptive neural crest region. In gain-of-function experiments, X-TSK can strongly enhance neural crest specification by the dorsolateral mesoderm or X-Wnt8 in ectodermal explants, while the electroporation of X-TSK mRNA in the lateral ectoderm of embryos after gastrulation can induce the expression of neural crest markers in vivo. By contrast, depletion of X-TSK in explants or embryos impairs neural crest specification. Similarly to its chick homolog, X-TSK works as a BMP antagonist by direct binding to BMP4. However, X-TSK can also indirectly regulate BMP4 mRNA expression at the neural plate border via modulation of the Delta-Notch signaling pathway. We show that X-TSK directly binds to the extracellular region of X-delta-1, and modulates Delta-dependent Notch activity. We propose that X-TSK plays a key role in neural crest formation by directly regulating BMP and Delta activities at the boundary between the neural and the non-neural ectoderm.
Heart and soul/PRKCi and nagie oko/Mpp5 regulate myocardial coherence and remodeling during cardiac morphogenesis
Authors: Rohr Stefan , Bit-Avragim Nana , Abdelilah-Seyfried Salim
Published: December 2005

Organ morphogenesis requires cellular shape changes and tissue rearrangements that occur in a precisely timed manner. Here, we show that zebrafish heart and soul (Has)/protein kinase C iota (PRKCi) is required tissue-autonomously within the myocardium for normal heart morphogenesis and that this function depends on its catalytic activity. In addition, we demonstrate that nagie oko (Nok) is the functional homolog of mammalian protein associated with Lin-seven 1 (Pals1)/MAGUK p55 subfamily member 5(Mpp5), and we dissect its earlier and later functions during myocardial morphogenesis. Has/PRKCi and Nok/Mpp5 are required early for the polarized epithelial organization and coherence of myocardial cells during heart cone formation. Zygotic nok/mpp5 mutants have later myocardial defects,including an incomplete heart tube elongation corresponding with a failure of myocardial cells to correctly expand in size. Furthermore, we show that nok/mpp5 acts within myocardial cells during heart tube elongation. Together, these results demonstrate that cardiac morphogenesis depends on the polarized organization and coherence of the myocardium, and that the expansion of myocardial cell size contributes to the transformation of the heart cone into an elongated tube.
Pax2/8-regulated Gata3 expression is necessary for morphogenesis and guidance of the nephric duct in the developing kidney
Authors: Grote David , Souabni Abdallah , Busslinger Meinrad , Bouchard Maxime
Published: December 2005

The mammalian pro- and mesonephros are transient embryonic kidneys essential for urogenital system development. The nephric (Wolffian) duct,which is a central constituent of both structures, elongates caudally along a stereotypical path to reach the hindlimb level where it induces metanephros(adult kidney) formation, while the remaining duct gives rise to the male genital tract (epidydimis, vas deferens). The transcription factors Pax2 and Pax8 are essential for the initiation of pro- and mesonephros development. In a cDNA microarray screen for genes specifically expressed in the pro/mesonephros and regulated by Pax proteins, we identified Gata3, a transcription factor gene associated with hypoparathyroidism, deafness and renal anomaly (HDR) syndrome. Gata3 is already expressed in the pronephric anlage, together with Pax2 and Pax8, suggesting that it may be a direct Pax2/8 target gene. Inactivation of Gata3 by insertion of an Ires-GFP reporter gene resulted in a massive increase in nephric duct cellularity, which was accompanied by enhanced cell proliferation and aberrant elongation of the nephric duct. Interestingly,however, the nephrogenic cord extended, with delayed kinetics, along the entire caudal path up to the level of the hindlimb bud, indicating that extension of the nephric duct and cord is controlled by different guidance cues. At the molecular level, the nephric duct of Gata3-/-embryos is characterized by the loss of Ret expression and signaling, which may contribute to the guidance defect of the nephric duct. Together, these results define Gata3 as a key regulator of nephric duct morphogenesis and guidance in the pro/mesonephric kidney.
Target-dependent specification of the neurotransmitter phenotype:cholinergic differentiation of sympathetic neurons is mediated in vivo by gp130 signaling
Authors: Stanke Matthias , Duong Chi Vinh , Pape Manuela , Geissen Markus , Burbach Guido , Deller Thomas , Gascan Hugues , Parlato Rosanna , Schütz Günther , Rohrer Hermann
Published: December 2005

Sympathetic neurons are generated through a succession of differentiation steps that initially lead to noradrenergic neurons innervating different peripheral target tissues. Specific targets, like sweat glands in rodent footpads, induce a change from noradrenergic to cholinergic transmitter phenotype. Here, we show that cytokines acting through the gp130 receptor are present in sweat glands. Selective elimination of the gp130 receptor in sympathetic neurons prevents the acquisition of cholinergic and peptidergic features (VAChT, ChT1, VIP) without affecting other properties of sweat gland innervation. The vast majority of cholinergic neurons in the stellate ganglion, generated postnatally, are absent in gp130-deficient mice. These results demonstrate an essential role of gp130-signaling in the target-dependent specification of the cholinergic neurotransmitter phenotype.
A Simple Kinetic Model for a Helium ICP
Authors: Fannin H. B. , Miller D. C. , Seliskar C. J.
Published: December 2005

A simple kinetic model is proposed to describe the population of the n3P and n1P states of helium for principle quantum numbers, n, from 3 to 10 in a 27-MHz ICP. The model incorporates two decay channels, namely those of radiative decay and collisional relaxation, to simulate the population. The functional form of the collision probability is approximated with the use of the Rydberg cross sections for the principal quantum number of the state. Experimental results are presented and are consistent with this model.
Combinations of Orthogonal Spectra to Estimate Component Spectra in Multicomponent Mixtures
Authors: Friedrich H. Bruce , Yu Jung-Pin
Published: December 2005

A factor analysis of a set of spectra of multicomponent mixtures yields n orthogonal spectra where n is the number of components in the mixtures. Combinations of these orthogonal spectra, done so as to eliminate the contributions to the spectra from one of the components, yield a set of n – 1 linearly independent abstract spectra. Repetition of this process is used to estimate the spectrum of each of the components without identifying the range of the n-dimensional vector space in which the solution must fall. Several techniques for estimating the appropriate combinations of orthogonal spectra are compared.
Quantitative Raman Spectroscopy of Homogeneous Molecular Profiles in Optical Waveguides via Direct Measurement
Authors: Miller D. R. , Han O. H. , Bohn P. W.
Published: December 2005

Quantitative measurements of Raman scattering from three-layer asymmetric slab dielectric waveguides made of organic macromolecular materials have been obtained from homogeneous distributions of scatterers as a function of mode by direct measurement of all mode-dependent quantities. For low-order modes, precision of the Raman intensity is limited to ∼5% by uncertainty in the measurement of the coupling coefficient, γ; while for high-order modes, precision was limited at the same level by uncertainty in the integrated electric field due to film-thickness variations. Observation of Raman instead of Rayleigh scatter vs. distance in the waveguide allowed measurement of the optical loss function, α, to be made down to 0.2 dB/cm with less than 1% uncertainty, so it is never the limiting factor.
Application of a Gas Sampling Introduction System for Inductively Coupled Plasma Spectroscopy and Analyses of Various Plasma Gases
Authors: Mautz Karl E. , Parsons Michael L. , Moore Carleton B.
Published: December 2005

An inductively coupled plasma spectrometer was modified for gaseous sample introduction. The system uses a gas proportioner utilizing rotameters to achieve sample gas concentrations and mixing with the sample argon gas. Modifications of instruments were performed to enhance stability and compatability of gaseous sample introduction. Instrument performance was characterized for optimization of spectral signals produced from plasma gases. Spectral analyses of gaseous samples including CF4, SF6, O2, N2, air, and mixtures of CF4-O2 and CF4-O2/N2 were performed. Identification of plasma gas and plasma-induced byproducts, both atomic and molecular, were determined.
Subcutaneous adipocytes from obese hyperinsulinemic women with polycystic ovary syndrome exhibit normal insulin sensitivity but reduced maximal insulin responsiveness
Authors: Lystedt Erika , Westergren Hanna , Brynhildsen Jan , Lindh-Åstrand Lotta , Gustavsson Johanna , Nystrom Fredrik H , Hammar Mats , Strålfors Peter
Published: December 2005

Background: Polycystic ovary syndrome (PCOS) has a high prevalence in women and is often associated with insulin resistance and hence with aspects of the so-called metabolic syndrome.

Methods: Ten women diagnosed with PCOS were consecutively included (aged 21–39 years, average 30.2 ± 1.9 years; body mass index 28.4–42.5 kg/m2, average 37.5 ± 1.7 kg/m2 (mean ± s.e.)). Adipocytes were isolated from the subcutaneous fat and, after overnight incubation to recover from insulin resistance due to the surgical cell isolation procedures, they were analyzed for insulin sensitivity.

Results: The patients with PCOS exhibited marked clinical hyperinsulinemia with 3.6-fold higher blood levels of C-peptide than a healthy lean control group (1.7 ± 0.2 and 0.5 ± 0.02 nmol/l respectively, P < 0.0001). The patients with PCOS also exhibited 2.4-fold higher concentrations of serum triacylglycerol (2.1 ± 0.3 and 0.9 ± 0.06 mmol/l respectively, P < 0.0001), but only slightly elevated blood pressure (118 ± 12/76 ± 6 and 113 ± 7/72 ± 6 mmHg respectively, P = 0.055/0.046). However, insulin sensitivity for stimulation of glucose transport in the isolated adipocytes was indistinguishable from a non-PCOS, non-diabetic control group, while the maximal insulin effect on glucose uptake was significantly lower (2.2 ± 0.2- and 3.8 ± 0.8-fold respectively, P = 0.02).

Conclusions: Subcutaneous adipocytes from patients with PCOS do not display reduced insulin sensitivity. The findings show that the insulin resistance of PCOS is qualitatively different from that of type 2 diabetes.
Diagnosis and management of pituitary tumours in the elderly: a review based on personal experience and evidence of literature
Authors: Minniti Giuseppe , Esposito Vincenzo , Piccirilli Manolo , Fratticci Amato , Santoro Antonio , Jaffrain-Rea Marie-Lise
Published: December 2005

An increasing proportion of pituitary adenomas are recognized in the elderly, raising the question of their optimal diagnosis and management. Age-related endocrine changes and associated diseases may significantly modify the clinical presentation and hormonal evaluation of these patients. About 80% of pituitary adenomas in this age group are non-secreting, requiring careful differential diagnosis with non-adenomatous sellar lesions. In this group, visual deterioration and hypopituitarism remain the leading symptoms. Recognized secreting tumours are mainly GH-secreting, most of them intrasellar, followed by prolactinomas, which present as clinically non-secreting and are usually invasive. Cushing’s disease appears as a very rare eventuality in the elderly. Optimal therapeutic management should aim to control the disease while preserving or improving patient’s quality of life. Transsphenoidal surgery has proved to be an efficient and well-tolerated option for non-secreting adenomas with visual defects and intrasellar GH-secreting adenomas, being able to improve metabolic and cardiovascular complications of acromegaly even in this age group. In contrast, dopamine-agonist drugs can be proposed as a primary therapy for prolactinomas even in the presence of severe neurological complications. Because the use of radiotherapy is hampered by its delay of action and potential neurological side effects, its indications should be better defined in this age group. The clinical importance of hypopituitarism should not be underestimated, and thyroid- and adrenal-replacement therapy are mandatory in the presence of documented hormone deficiency, carefully avoiding overtreatment in order to limit possible side effects on the cardiovascular system and bone mineralization. Indications for GH- and sex steroid-replacement therapy still await age-specific guidelines.
Monocyte chemoattractant protein 1: a possible link between visceral adipose tissue-associated inflammation and subclinical echocardiographic abnormalities in uncomplicated obesity
Authors: Malavazos Alexis E , Cereda Emanuele , Morricone Lelio , Coman Calin , Corsi Massimiliano M , Ambrosi Bruno
Published: December 2005

Objective: Obesity can be considered a state of chronic, low-grade inflammation. Particularly, visceral adipose tissue (VAT) seems to be an active compartment in pro-inflammatory molecule secretion. Adipocytes and VAT are able to produce large amounts of monocyte chemoattractant protein 1 (MCP-1), a chemokine directly involved in ventricular remodeling.

Design: In this study, the possible existence of a correlation between MCP-1, abdominal fat accumulation and echocardiographic abnormalities in uncomplicated obesity was investigated.

Methods: Echocardiographic parameters, MCP-1 and C-reactive protein (CRP) levels were assessed in 27 normotensive obese women of fertile age (body mass index 43.5 ± 4.8 kg/m2, mean ± s.d.) and 15 normal weight women. Visceral fat (VAT) in the obese group was assessed by computed tomography.

Results: Obese patients had higher MCP-1 (P < 0.0001) and CRP (P < 0.0001) levels than controls. MCP-1 levels were correlated with VAT area (r = 0.57, P < 0.0001), CRP (P < 0.0001), left ventricular mass (LVM) (P < 0.02), LVM indexed for height (P < 0.03), end-diastolic posterior wall (P < 0.005), relative wall thickness (P < 0.01), early diastolic filling wave velocity (P < 0.01), isovolumetric relaxation time (P < 0.001) and deceleration time (P < 0,01). Obese patients with greater amounts of VAT (> 130 cm2) presented higher MCP-1 (P < 0.0001) and CRP levels (P < 0.04) than those with a lower degree of abdominal adiposity.

Conclusions: MCP-1 levels and visceral adipose tissue seem to be associated with some morphological and functional echocardiographic abnormalities and support a role for visceral fat in predisposing the subject to cardiac dysfunction, possibly through a low-grade state of inflammation.
GH treatment reduces trunkal adiposity in HIV-infected patients with lipodystrophy: a randomized placebo-controlled study
Authors: Luzi Livio , Meneghini Elena , Oggionni Sabrina , Tambussi Giuseppe , Piceni-Sereni Lucia , Lazzarin Adriano
Published: December 2005

Objective: HIV lipodystrophy is a common complication of highly active anti-retroviral therapy, characterized by both metabolic and morphological features. The most feared morphological feature is body fat redistribution leading to HIV lipodystrophy. GH is known to induce reduction of visceral obesity and body fat redistribution in adults.

Design: A crossover, double-blind protocol of GH treatment (6 months of recombinant human GH (rhGH) at 0.2 IU/kg per week) vs placebo (6 months of placebo with a 2 month wash-out between periods) was performed.

Subjects and setting: Thirty HIV-infected patients with lipodystrophy were recruited in the Outpatient Clinic of the Division of Infectious Diseases of San Raffaele Scientific Institute in Milan, Italy.

Main outcome and results: Our data demonstrate an effect of low-dose rhGH administration in reducing trunk adiposity in HIV patients with lipodystrophy (Δ from basal: −394 ± 814 g, P = 0.048 with respect to placebo. Data are given as mean ± standard deviation). A trend to an increase of arm depots was also shown (Δ from basal: +43 ± 384 g, P = NS with respect to placebo). Interestingly, no detrimental metabolic effects on glucose tolerance and lipid levels were found following the administration of 0.2 IU/kg per week of rhGH for 6 months.

Conclusions: Low-dose GH administration is an effective treatment in reducing trunk obesity in HIV-infected patients with lipodystrophy.
Glomerular filtration rate in patients with Cushing’s disease: a matched case–control study
Authors: Haentjens P , De Meirleir L , Abs R , Verhelst J , Poppe K , Velkeniers B
Published: December 2005

Background: Patients with Cushing’s disease have a high prevalence of atherosclerosis and maintain an increased cardiovascular risk even after cure of the disease. However, the impact of Cushing’s disease on renal function remains to be quantified.

Objectives: To evaluate glomerular filtration rate (GFR) and to identify predictors of GFR in patients with Cushing’s disease.

Design and methods: We conducted a matched case–control study: 18 patients with active or cured Cushing’s disease were compared with healthy population controls matched for age and sex. The main outcome measures were GFR and micro-albuminuria.

Results: Patients with Cushing’s disease had a lower GFR, as measured by 24-h creatinine clearance (79 versus 95 ml/min per 1.73 m2, P = 0.005) and estimated by the MDRD2 formula (75 versus 88 ml/min per 1.73 m2, P = 0.008). Multiple regression analyses indicated that disease duration was the strongest predictor for a worse GFR. The prevalence of micro-albuminuria was low (5.5% in both groups).

Conclusions: Patients with Cushing’s disease have a decreased GFR. Even if they are cured, close follow-up with strict control of cardiovascular risk factors and monitoring of GFR seems mandatory. Furthermore, the dosage of certain drugs should be adapted to the individual GFR.
Evaluation of the effectiveness of midnight serum cortisol in the diagnostic procedures for Cushing’s syndrome
Authors: Reimondo Giuseppe , Allasino Barbara , Bovio Silvia , Paccotti Piero , Angeli Alberto , Terzolo Massimo
Published: December 2005

Objective: It is presently unclear whether the accuracy of midnight serum cortisol (F24) in the diagnosis of Cushing’s syndrome (CS) may be replicated under usual conditions of clinical care. The aim of the present study was to assess retrospectively the effectiveness of F24 for confirming the diagnosis in a consecutive series of 106 patients, in 78 of whom a definitive diagnosis of CS was made.

Design and methods: We have compared the results of F24, urinary free cortisol (UFC) and the overnight 1 mg dexamethasone suppression test (DST) with the definitive clinical diagnosis. Receiver operating characteristic (ROC) analysis has been performed to define the best cutoff values, the sensitivity (Se) and the specificity (Sp) of the tests.

Results: The best cutoff value for F24 was 8.3 μg/dl (Se 91.8%; Sp 96.4%). The best cutoff value for the DST was 4.0 μg/dl (Se 89.2%; Sp 90.9%). The best cutoff value for UFC was 238 μg/24 h (Se 73.2%; Sp 96.3%). The area under the curve of F24 was significantly greater than that of UFC, both in the overall series (P = 0.004) and in the subgroup of patients with mild CS (P = 0.02). The differences were analyzed by means of the two-tailed students’s t-test. With the thresholds generated by the ROC analysis, UFC would have failed to achieve the correct diagnosis in a significantly higher percentage of cases than F24 (20.4% vs 7.9%; P = 0.01). The difference was analyzed by means of the chi-squared test with Yates correction.

Conclusions: The present results show that F24 has excellent effectiveness in the diagnostic procedures for CS in stressed conditions (patients studied in a hospital ward in a nonsleeping state). The test appears to be accurate also for patients with mild hypercortisolism.
Association of subclinical hypercortisolism with type 2 diabetes mellitus: a case-control study in hospitalized patients
Authors: Chiodini Iacopo , Torlontano Massimo , Scillitani Alfredo , Arosio Maura , Bacci Simonetta , Di Lembo Sergio , Epaminonda Paolo , Augello Giovanni , Enrini Riccardo , Ambrosi Bruno , Adda Guido , Trischitta Vincenzo
Published: December 2005

Objective: Subclinical hypercortisolism (SH) may play a role in several metabolic disorders, including diabetes. No data are available on the relative prevalence of SH in type 2 diabetes (T2D). In order to compare the prevalence of SH in T2D and matched non-diabetic control individuals, we performed a case-controlled, multicenter, 12-month study, enrolling 294 consecutive T2D inpatients (1.7% dropped out the study) with no evidence of clinical hypercortisolism and 189 consecutive age- and body mass index-matched non-diabetic inpatients (none of whom dropped out).

Design and methods: Ascertained SH (ASH) was diagnosed in individuals (i) with plasma cortisol after 1 mg overnight dexamethasone suppression >1.8 μg/dl (50 nmol/l), (ii) with more than one of the following: (a) urinary free cortisol >60.0 μg/24 h (165.6 nmol/24 h), (b) plasma ACTH <10.0 pg/ml (2.2 pmol/l) or (c) plasma cortisol >7.5 μg/dl (207 nmol/l) at 24:00 h or >1.4 μg/dl (38.6 nmol/l) after dexamethasone-CRH (serum cortisol after corticotrophin-releasing hormone stimulus during dexamethasone administration) test, and (iii) in whom the source of glucocorticoid excess was suggested by imaging and by additional biochemical tests (for ACTH-dependent ASH).

Results: Prevalence of ASH was higher in diabetic individuals than in controls (9.4 versus 2.1%; adjusted odds ratio, 4.8; 95% confidence interval, 1.6–14.1; P = 0.004). In our population the proportion of T2D which is statistically attributable to ASH was approx. 7%. Among diabetic patients, the presence of severe diabetes (as defined by the coexistence of hypertension, dyslipidaemia and insulin treatment) was significantly associated with SH (adjusted odds ratio, 3.8; 95% confidence interval, 1.4–10.2; P = 0.017).

Conclusions: In hospitalized patients, SH is associated with T2D.
Expression profile of serotonin4 (5-HT4) receptors in adrenocortical aldosterone-producing adenomas
Authors: Cartier Dorthe , Jégou Sylvie , Parmentier Françoise , Lihrmann Isabelle , Louiset Estelle , Kuhn Jean-Marc , Bastard Christian , Plouin Pierre-François , Godin Michel , Vaudry Hubert , Lefebvre Hervé
Published: December 2005

Objective: We aimed to investigate the expression profile of serotonin4 (5-HT4) receptors in adrenocortical aldosterone-producing adenoma (APA) tissues in comparison with normal adrenal cortex.

Design and methods: Total 5-HT4 receptor mRNAs were quantified by real-time quantitative polymerase chain reaction (PCR) assay, and the mRNAs encoding the 5-HT4 receptor isoforms were characterized by reverse transcription (RT)–PCR in seven normal adrenal cortices and 11 APA tissues. The distribution of 5-HT4 receptor mRNAs was investigated by in situ hybridization in both normal adrenal and APA tissues, and the presence of 5-HT in APA tissues was studied by immunohistochemistry.

Results: Real-time PCR analysis revealed that 5-HT4 receptor mRNA expression was 4.7–47 times higher in APA tissues than in normal glands. In situ hybridization studies showed that 5-HT4 receptor mRNAs were expressed in both zona glomerulosa and zona fasciculata/reticularis of the normal cortex and in groups of APA steroidogenic cells disseminated in the tumor tissues. Characterization of 5-HT4 receptor splice variants by RT–PCR revealed different profiles of expression in APAs versus normal adrenals. Isoforms (a) and (b) were not expressed in any APA but were present in the majority of normal adrenocortical tissues. Conversely, isoform (d) was expressed in 5/11 APAs but only in 1/7 adrenals. Immunohistochemical studies revealed the presence of 5-HT-immunoreactivity in both mast cells and clusters of steroidogenic cells in APA tissues.

Conclusion: Our results show overexpression and different splicing of the 5-HT4 receptor in APA tissues in comparison with normal adrenocortical tissue. They also demonstrate the presence of 5-HT in both mast cells and tumor steroidogenic cells, providing evidence for a possible autocrine/paracrine activation of aldosterone secretion within adenoma tissues.
The tapeworm Ligula intestinalis (Cestoda: Pseudophyllidea) inhibits LH expression and puberty in its teleost host, Rutilus rutilus
Authors: Carter V , Pierce R , Dufour S , Arme C , Hoole D
Published: December 2005

The tapewormLigula intestinalisoccurs in the body cavity of its cyprinid second intermediate host, in this study the roachRutilus rutilus, and inhibits host gonadal development. The mechanism by which infected fish are prevented from reproducing is unknown. Comparison of parameters, such as body length and weight, and condition factor and age, between infected and uninfected individuals, indicated only minor effects of parasitism on growth and condition. In contrast, seasonal gonadal development, as observed in uninfected fish, did not occur in infected fish, and gonads remained small and blocked at the primary oocyte stage in female roach. As immature ovaries and testes are still present, the parasite is presumed to act upon the brain–pituitary–gonadal axis of the fish to inhibit further development of reproductive organs. We investigated theLigula/fish interaction at the level of the pituitary gland by determination of gonadotrophin (LH) content using a heterologous RIA for carp (Cyprinus carpio) LHβ subunit. The results indicated that the pituitary glands of infected roach contained approximately 50% less LH than non-infected fish. After the cloning and sequencing of roach LHβ subunit, we measured roach LHβ mRNA levels by real-time RT-PCR. A corresponding 50% reduction in LHβ mRNA pituitary levels was determined. These results reflect a significant and measurable effect of parasitism on the pituitary gland, and lend support to the hypothesis that excretory/secretory products released from the parasite interact with the brain–pituitary–gonadal axis of the fish host and thus inhibit gonadal development.
A proteomic analysis of mammalian preimplantation embryonic development
Authors: Katz-Jaffe Mandy G , Linck Donald W , Schoolcraft William B , Gardner David K
Published: December 2005

Genetic studies on the mammalian preimplantation embryo are providing a wealth of information regarding gene expression. However, changes in the transcriptome do not always reflect cellular function or the complexity and diversity of the mammalian proteome with post-translational modifications or protein–protein interactions. To elucidate embryonic cellular function, a detailed understanding at the protein level is necessary. The aim of this study was to generate protein profiles of mammalian embryos throughout development, and to investigate the effects of oxygen concentration on the embryonic proteome. A protocol was developed to analyse small groups of embryos (n = 5) by time-of-flight mass spectrometry. F1 mice zygotes were cultured in G1/G2 sequential media with recombinant albumin (2.5 mg/ml) in 6% CO2 and O2 concentrations of either 5% or 20%. In vivo-developed embryos were flushed from the reproductive tract (day 4). Protein profiles were generated for all embryonic samples and statistical analysis revealed 32 potential proteins/biomarkers with significant changes (P < 0.05). Embryos generated under 5% O2 more closely resembled in vivo-developed embryos. Under 20% O2 conditions, embryos showed down-regulation of 10 proteins/biomarkers (masses between 4 to 20 kDa) (P < 0.05) confirming the pathological effects of oxygen during embryonic development. These data demonstrate for the first time the complexity of the mammalian preimplantation proteome. The unique protein profiles of in vivo-developed embryos and a panel of selected biomarkers represent optimal cellular function, against which comparisons can be made to facilitate improvements in mammalian assisted reproduction techniques procedures.
From egg to embryo: a peripatetic journey
Authors: Schultz Richard M
Published: December 2005

The recent surge of interest in oocyte development has been spurred in large part by the increasing implementation of assisted reproductive technologies (ART) to treat human infertility. What is becoming apparent is that ‘egg quality’ is a primary factor in the success of ART (Sauer 1998), and yet we know virtually nothing about the molecular signature of a ‘high quality’ oocyte, i.e., an oocyte that is capable of maturing, being fertilized and supporting development to term. We are gaining marked insights, however, into how sperm activate eggs and the changes in gene expression that accompany preimplantation development. Nevertheless, embryo culture is known to effect gene expression (Rinaudo & Schultz 2004), the long-term consequences of which are only recently being unmasked. This review will briefly highlight these topics that were presented during the Biennial Joint Meeting of the UK Fertility Societies at Warwick University in April 2005.
Germ cell fate and seminiferous tubule development in bovine testis xenografts
Authors: Rathi Rahul , Honaramooz Ali , Zeng Wenxian , Schlatt Stefan , Dobrinski Ina
Published: December 2005

Spermatogenesis can occur in testis tissue from immature bulls ectopically grafted into mouse hosts; however, efficiency of sperm production is lower than in other donor species. To elucidate a possible mechanism for the impaired spermatogenesis in bovine testis xenografts, germ cell fate and xenograft development were investigated at different time points and compared with testis tissue from age-matched calves as controls. Histologically, an initial decrease in germ cell number was noticed in xenografts recovered up to 2 months post-grafting without an increase in germ cell apoptosis. From 2 months onward, the number of germ cells increased. In contrast, a continuous increase in germ cell number was seen in control tissue. Pachytene spermatocytes were observed in some grafts before 4 months, whereas in the control tissue they were not present until 5 months of age. Beyond 4 months post-grafting spermatogenesis appeared to be arrested at the pachytene spermatocyte stage in most grafts. Elongated spermatids were observed between 6 and 8 months post-grafting, similar to the controls, albeit in much lower numbers. Lumen formation started earlier in grafts compared with controls and by 6 months post-grafting tubules with extensively dilated lumen were observed. A donor effect on efficiency of spermatogenesis was also observed. These results indicate that the low efficiency of sperm production in bovine xenografts is due to an initial deficit of germ cells and impaired meiotic and post-meiotic differentiation. The characterization of spermatogenic efficiency will provide the basis to understand the control of spermatogenesis in testis grafts.
Increased disruption of sperm plasma membrane at sperm immobilization promotes dissociation of perinuclear theca from sperm chromatin after intracytoplasmic sperm injection in pigs
Authors: Katayama Mika , Sutovsky Peter , Yang Boh S , Cantley Tom , Rieke August , Farwell Randy , Oko Richard , Day Billy N
Published: December 2005

The effects of sperm-immobilization methods on decondensation of sperm chromatin and retention of subacrosomal sperm perinuclear theca (SAR-PT) after intracytoplasmic sperm injection (ICSI) were examined in pigs. Sperm membrane damage caused by different immobilization methods by rubbing with a micropipette without piezo pulses (R), or with a low (L) or high (H) intensity of piezo pulses while rubbing, was assessed by the time required for staining of sperm heads with eosin Y solution. The average time for staining of sperm heads immobilized by the R, L or H treatments was 76, 41 or 26 s, respectively. The fertilization rate following ICSI was increased by sperm immobilization by piezo pulses compared with R, but increased intensity of pulses from L to H did not cause further improvements (29, 48 and 47%, respectively). An immunofluorescence study revealed that H immobilization promoted the dissociation of SAR-PT from sperm chromatin compared with L and R, and it increased the frequency of male pronuclear formation in which chromatin appeared uniformly decondensed. Within vitrofertilization (IVF), SAR-PT disassembled coordinately with sperm chromatin decondensation and it was not detectable around male pronuclei. This was different from most of the oocytes after ICSI in which remnants SAR-PT were detected adjacent to male pronuclei. We concluded that increased damage on the sperm plasma membrane at immobilization improved fertilization rates and decondensation of sperm chromatin after ICSI due to the accelerated dissociation of SAR-PT from the sperm nucleus. Also, the behavior of SAR-PT after ICSI was different from that observed in oocytes after IVF.
Electronic Surveillance System for Monitoring Surgical Antimicrobial Prophylaxis
Authors: Voit Sara Bornstein , Todd James K. , Nelson Bernard , Nyquist Ann-Christine
Published: December 2005

Objectives. Antimicrobial surgical prophylaxis comprises one third of all antibiotic use in pediatric hospitals and 80% of all antibiotic use in surgery. Previous studies reported that antimicrobial surgical prophylaxis is often inconsistent with recommended guidelines. An electronic surveillance system was developed to measure antimicrobial utilization and to identify opportunities to improve and monitor the administration of antibiotics for surgical prophylaxis.

Methods. A retrospective cohort study was conducted on patients with selected inpatient surgical procedures performed from May 1999 to April 2000 at 4 US children’s hospitals. International Classification of Diseases, Ninth Revision surgical procedure codes were divided into clean or unclean categories, and an electronic surveillance system was designed using antibiotic and microbiologic culture utilization data to measure appropriate antimicrobial use associated with the surgical procedure. A medical chart review was conducted to validate the electronic system.

Results. Ninety percent of cases were classified properly by the electronic surveillance system as confirmed by medical chart review. Surgical antibiotic prophylaxis was not in accordance with the American Academy of Pediatrics (AAP) guidelines for almost half of all procedures. Prolonged antimicrobial administration in clean surgical procedures was the most frequent deviation from guidelines. Statistical differences between the index hospital and the comparison hospitals reflect both over- and underutilization of surgical prophylaxis with significant opportunity to improve prophylaxis for all hospitals.

Conclusions. Antimicrobial surgical prophylaxis at the children’s hospitals studied is not always consistent with published AAP guidelines. This electronic surveillance system provides a rapid, reproducible, and validated tool to measure easily the efforts to improve adherence to AAP surgical prophylaxis guidelines.
Using a Preprinted Order Sheet to Reduce Prescription Errors in a Pediatric Emergency Department: A Randomized, Controlled Trial
Authors: Kozer Eran , Scolnik Dennis , MacPherson Alison , Rauchwerger David , Koren Gideon
Published: December 2005

Objective. Medication errors are common among pediatric patients and in emergency departments (EDs). Such errors may lead to prolonged hospitalization, unnecessary diagnostic tests and treatments, and death. The objective of this study was to determine whether the use of a structured order sheet reduces the incidence of medication errors in a pediatric ED.

Methods. The study was a randomized, controlled study that was conducted in a tertiary care pediatric hospital. Eighteen days were randomized into 2 study groups: days during which the regular blank order sheets were used and days during which preprinted, formatted, order sheets were used. All patients’ charts from these days were reviewed by 2 medical students, who extracted demographic, clinical, and therapeutic data into a database. Two pediatric emergency physicians, blinded to the form used, reviewed the database and independently decided whether an error had occurred and the severity of the error.

Results. Within the study period, there were 2157 visits to the ED. A total of 2058 (95.4%) charts were available for review. A total of 411 (52.2%) orders for drugs in the ED were ordered on the regular form, and 376 (47.8%) were given on the new form. Drug errors were identified in 68 (16.6%) orders when the regular form was used and in 37 (9.8%) of the orders on the new form. Using the new form was associated with a significant reduction in the risk for an error (odds ratio: 0.55; 95% confidence interval: 0.34–0.90).

Conclusions. The use of a preprinted structured order form significantly reduces medication errors among pediatric patients in the ED.
High Antidiuretic Hormone Levels and Hyponatremia in Children With Gastroenteritis
Authors: Neville Kristen A. , Verge Charles F. , O'Meara Matthew W. , Walker Jan L.
Published: December 2005

Objectives. Nonosmotic antidiuretic hormone (ADH) activity can cause severe hyponatremia during involuntary fluid administration. We looked for evidence of this before and during intravenous (IV) fluid administration in children treated for gastroenteritis.

Methodology. In this prospective observational study, plasma ADH, electrolytes, osmolality, and glucose were measured in 52 subjects before (T0) and 4 hours after (T4) starting 0.45% saline + 2.5% dextrose and subsequently when indicated. Hormonal markers of stress were measured at T0. Urine samples were collected to measure electrolytes and osmolality.

Results. The nonosmotic stimuli of ADH secretion that we identified were vomiting (50 of 52), dehydration (median: 5%; range: 3–8%), hypoglycemia (2 of 52), and raised hormonal markers of stress (mean ± SD: cortisol, 1094 ± 589 nmol/L; reverse triiodothyronine, 792 ± 293 pmol/L). At T0, half the children were hyponatremic (plasma sodium concentration of <135 mmol/L; n = 27). The median plasma ADH concentration at T0 was significantly elevated (median: 7.4 pg/mL; range: <1.9–85.6 pg/mL). ADH was high in both hyponatremic and normonatremic children and remained high at T4 in 33 of the 52 children, 22 of whom were concurrently hyponatremic. At T4, mean plasma sodium concentration was unchanged in the hyponatremic children but was 2.6 mmol/L (±2.0) lower in those who were initially normonatremic. Urine tonicity was high compared with 0.45% saline in 16 of 19 children at baseline and in 20 of 37 children after 3 to 12 hours of IV fluids.

Conclusions. Nonosmotic stimuli of ADH secretion are frequent in children with gastroenteritis. Their persistence during IV-fluid administration predisposes to dilutional hyponatremia. The use of hypotonic saline for deficit replacement needs to be reassessed.
Content of Communication by Pediatric Residents After Newborn Genetic Screening
Authors: Farrell Michael H. , La Pean Alison , Ladouceur Lynnea
Published: December 2005

Background. Newborn screening saves lives, but psychosocial complications after genetic screening have led to doubts about expanding programs. Because complications have been blamed on ineffective communication of results, a population-scale system to ensure communication quality may improve outcomes. The objective of this study was to develop and evaluate a method to assess the content of communication after newborn genetic screening.

Methods. We abstracted content data and calculated quantitative scores for 3 communication quality indicators (key content, early placement of good news, and excessive background content) for 59 transcribed conversations between pediatric residents and simulated parents of an “infant” who was found via newborn screening to carry either cystic fibrosis or sickle cell hemoglobinopathy.

Results. Only 8.5% of transcripts contained the key content items that were thought to be necessary for parental understanding; 27.1% included reassuring news about carrier status within the first 10% of content. Scores for 3 quality indicators fell in the low performance range in 35.6%, 30.5%, and 27.1% of transcripts, respectively. The most common topic was background about the disease (22% of content statements) even though the infant did not have the disease. Surprisingly, 50% of sickle trait transcripts included counseling about a possible risk for sudden death.

Conclusions. Assessment of the content domain of communication quality identified some high-quality communication interspersed with many missed opportunities. If integrated into newborn screening, our method may help to alleviate some of society's ethical concerns about benefit and risk after newborn and other genetic screening.
Criminally Prosecuted Cases of Child Starvation
Authors: Kellogg Nancy D. , Lukefahr James L.
Published: December 2005

Objective. Here we describe the clinical findings and legal outcomes in 12 prosecuted cases of infant and child starvation.

Methods. Medical records, investigation records, and transcripts of court testimony were reviewed in the cases of 12 infants and children from locations throughout Texas who had been starved deliberately. The children’s ages ranged from 2 months to 13 years. The caretakers of all children received both civil and criminal charges; cases were tried over an 11-year time span. Clinical presentations, examination findings, laboratory findings, symptoms of refeeding syndrome, and legal outcomes were examined. Two illustrative cases are presented in detail here.

Results. Of the 12 cases reviewed, the median age was 2.7 years, with a range of 2.25 months to 13 years 7 months. Half of the children died shortly before or soon after presentation for medical care or to law enforcement. Survival was more common in older children than in infants. Most of the children were secluded from others, and all had access to food denied or severely restricted. Caretakers claimed few, benign, or no past medical illnesses in the children. Based on weight and height measurements, 10 of the children had severe wasting and stunting, and 2 had mild or moderate wasting. There was a tendency toward more severe wasting in the fatal cases. All children manifested multiorgan effects of starvation. All survivors manifested complications with refeeding. Approximately half of the children had past or present injuries or history suggestive of physical or sexual abuse. Parental rights were terminated in all cases. A total of 25 individuals were charged criminally; 23 were found guilty or pled guilty, and trials for 2 individuals were pending at the time of this writing. The types of criminal charges and punishment varied from deferred adjudication to a life sentence.

Conclusions. Life-threatening criminal starvation of infants and children is a rare and severe form of child maltreatment. In our series, infants were more wasted at the time of presentation and less likely to survive prolonged starvation than were older children. As with other forms of child abuse, caretakers’ histories regarding the children’s illnesses were inconsistent with the severity and chronicity of the children’s degree of wasting. All victims in our series showed multiorgan effects of chronic malnutrition and deprivation, and all survivors developed refeeding complications and required prolonged periods of recovery.
A Limited Measles Outbreak in a Highly Vaccinated US Boarding School
Authors: Yeung Lorraine F. , Lurie Perrianne , Dayan Gustavo , Eduardo Eduard , Britz Phyllis H. , Redd Susan B. , Papania Mark J. , Seward Jane F.
Published: December 2005

Objectives. We investigated a measles outbreak that began in March 2003 in a Pennsylvania boarding school with >600 students to identify all cases, including the source; implement outbreak control measures; and evaluate vaccine effectiveness.

Methods. Measles was suspected in any person at the school with a generalized rash and fever during March 21 to May 28, 2003 and investigated with serologic testing. We reviewed vaccination history from school records and conducted a survey to determine country of measles vaccination. Vaccine effectiveness was calculated using the cohort method.

Results. We identified 9 laboratory-confirmed cases at the school: 8 students and 1 staff member. Among them, 2 had never received any doses of measles-containing vaccine (MCV), 1 received 1 dose of MCV, and 6 received 2 doses of MCV. Three of the 6 who received 2 doses of MCV received both doses outside the United States. The source case had been infected in Lebanon. Two laboratory-confirmed spread cases were identified in New York City. Measles virus of genotype D4 was isolated in cases from the school and New York City. Of the 663 students in the school, 8 (1.2%) had never received any doses of MCV, 26 (3.9%) had received 1 dose, and 629 (94.9%) had received 2 doses before the outbreak. Vaccine effectiveness among students who had received 2 doses of MCV was 98.6%. However, students who received both doses outside the United States had a higher attack rate (3 of 75) than those who received both doses in the United States (3 of 509; rate ratio: 6.8; 95% confidence interval: 1.4–33.0).

Conclusions. This is the largest measles outbreak to occur in a school in the United States since 1998, but it was limited to only 9 cases in a boarding school with >600 students. The limited extent of this outbreak highlights the high level of population immunity achieved in the United States through widespread implementation of a 2-dose measles-mumps-rubella vaccination strategy in school-aged children. States and schools should continue to enforce strictly the 2-dose measles-mumps-rubella vaccination requirement and, in an outbreak setting, consider revaccinating students who received measles vaccine outside of the United States. Continued vigilance by health care providers is needed to recognize measles cases.