Mitotic gene regulation by the N-MYC-WDR5-PDPK1 nexus

BACKGROUND

During mitosis the cell depends on proper attachment and segregation of replicated chromosomes to generate two identical progeny. In cancers defined by overexpression or dysregulation of the MYC oncogene this process becomes impaired, leading to genomic instability and tumor evolution. Recently it was discovered that the chromatin regulator WDR5-a critical MYC cofactor-regulates expression of genes needed in mitosis through a direct interaction with the master kinase PDPK1. However, whether PDPK1 and WDR5 contribute to similar mitotic gene regulation in MYC-overexpressing cancers remains unclear. Therefore, to characterize the influence of WDR5 and PDPK1 on mitotic gene expression in cells with high MYC levels, we performed a comparative transcriptomic analysis in neuroblastoma cell lines defined by MYCN-amplification, which results in high cellular levels of the N-MYC protein.

RESULTS

Using RNA-seq analysis, we identify the genes regulated by N-MYC and PDPK1 in multiple engineered CHP-134 neuroblastoma cell lines and compare them to previously published gene expression data collected in CHP-134 cells following inhibition of WDR5. We find that as expected N-MYC regulates a multitude of genes, including those related to mitosis, but that PDPK1 regulates specific sets of genes involved in development, signaling, and mitosis. Analysis of N-MYC- and PDPK1-regulated genes reveals a small group of commonly controlled genes associated with spindle pole formation and chromosome segregation, which overlap with genes that are also regulated by WDR5. We also find that N-MYC physically interacts with PDPK1 through the WDR5-PDPK1 interaction suggesting regulation of mitotic gene expression may be achieved through a N-MYC-WDR5-PDPK1 nexus.

CONCLUSIONS

Overall, we identify a small group of genes highly enriched within functional gene categories related to mitotic processes that are commonly regulated by N-MYC, WDR5, and PDPK1 and suggest that a tripartite interaction between the three regulators may be responsible for setting the level of mitotic gene regulation in N-MYC amplified cell lines. This study provides a foundation for future studies to determine the exact mechanism by which N-MYC, WDR5, and PDPK1 converge on cell cycle related processes.

Super-Enhancer Dysregulation in Rhabdoid Tumor Cells Is Regulated by the SWI/SNF ATPase BRG1

Mutations in the SWI/SNF chromatin remodeling complex occur in ~20% of cancers. In rhabdoid tumors defined by loss of the SWI/SNF subunit SMARCB1, dysregulation of enhancer-mediated gene expression is pivotal in driving oncogenesis. Enhancer dysregulation in this setting is tied to retention of the SWI/SNF ATPase BRG1-which becomes essential in the absence of SMARCB1-but precisely how BRG1 contributes to this process remains unknown. To characterize how BRG1 participates in chromatin remodeling and gene expression in SMARCB1-deficient cells, we performed a genome-wide characterization of the impact of BRG1 depletion in multiple rhabdoid tumor cell lines. We find that although BRG1-regulated open chromatin sites are distinct at the locus level, the biological characteristics of the loci are very similar, converging on a set of thematically related genes and pointing to the involvement of the AP-1 transcription factor. The open chromatin sites regulated by BRG1 colocalize with histone-marked enhancers and intriguingly include almost all super-enhancers, revealing that BRG1 plays a critical role in maintaining super-enhancer function in this setting. These studies can explain the essentiality of BRG1 to rhabdoid tumor cell identity and survival and implicate the involvement of AP-1 as a critical downstream effector of rhabdoid tumor cell transcriptional programs.

Generation of TWO G51D SNCA missense mutation iPSC lines (CRICKi011-A, CRICKi012-A) from two individuals at risk of Parkinson's disease

Mutations or multiplications of the SNCA (Synuclein Alpha) gene cause rare autosomal dominant Parkinson's disease (PD). The SNCA G51D missense mutation is associated with a synucleinopathy that shares PD and multiple system atrophy (MSA) characteristics. We generated induced pluripotent stem cell (iPSC) lines from two individuals with SNCA G51D missense mutations at risk of PD. Dermal fibroblasts were reprogrammed to pluripotency using a non-integrating mRNA-based protocol. The resulting human iPSCs displayed normal morphology, expressed markers associated with pluripotency, and differentiated into the three germ layers. The iPSC lines could facilitate disease-modelling and therapy development studies for synucleinopathies.

Prediction of mechanistic subtypes of Parkinson's using patient-derived stem cell models

Parkinson's disease is a common, incurable neurodegenerative disorder that is clinically heterogeneous: it is likely that different cellular mechanisms drive the pathology in different individuals. So far it has not been possible to define the cellular mechanism underlying the neurodegenerative disease in life. We generated a machine learning-based model that can simultaneously predict the presence of disease and its primary mechanistic subtype in human neurons. We used stem cell technology to derive control or patient-derived neurons, and generated different disease subtypes through chemical induction or the presence of mutation. Multidimensional fluorescent labelling of organelles was performed in healthy control neurons and in four different disease subtypes, and both the quantitative single-cell fluorescence features and the images were used to independently train a series of classifiers to build deep neural networks. Quantitative cellular profile-based classifiers achieve an accuracy of 82%, whereas image-based deep neural networks predict control and four distinct disease subtypes with an accuracy of 95%. The machine learning-trained classifiers achieve their accuracy across all subtypes, using the organellar features of the mitochondria with the additional contribution of the lysosomes, confirming the biological importance of these pathways in Parkinson's. Altogether, we show that machine learning approaches applied to patient-derived cells are highly accurate at predicting disease subtypes, providing proof of concept that this approach may enable mechanistic stratification and precision medicine approaches in the future.

Protein aggregation and calcium dysregulation are hallmarks of familial Parkinson's disease in midbrain dopaminergic neurons

Mutations in the SNCA gene cause autosomal dominant Parkinson's disease (PD), with loss of dopaminergic neurons in the substantia nigra, and aggregation of α-synuclein. The sequence of molecular events that proceed from an SNCA mutation during development, to end-stage pathology is unknown. Utilising human-induced pluripotent stem cells (hiPSCs), we resolved the temporal sequence of SNCA-induced pathophysiological events in order to discover early, and likely causative, events. Our small molecule-based protocol generates highly enriched midbrain dopaminergic (mDA) neurons: molecular identity was confirmed using single-cell RNA sequencing and proteomics, and functional identity was established through dopamine synthesis, and measures of electrophysiological activity. At the earliest stage of differentiation, prior to maturation to mDA neurons, we demonstrate the formation of small β-sheet-rich oligomeric aggregates, in SNCA-mutant cultures. Aggregation persists and progresses, ultimately resulting in the accumulation of phosphorylated α-synuclein aggregates. Impaired intracellular calcium signalling, increased basal calcium, and impairments in mitochondrial calcium handling occurred early at day 34-41 post differentiation. Once midbrain identity fully developed, at day 48-62 post differentiation, SNCA-mutant neurons exhibited mitochondrial dysfunction, oxidative stress, lysosomal swelling and increased autophagy. Ultimately these multiple cellular stresses lead to abnormal excitability, altered neuronal activity, and cell death. Our differentiation paradigm generates an efficient model for studying disease mechanisms in PD and highlights that protein misfolding to generate intraneuronal oligomers is one of the earliest critical events driving disease in human neurons, rather than a late-stage hallmark of the disease.

Mitochondrial dysfunction is a key pathological driver of early stage Parkinson's

BACKGROUND

The molecular drivers of early sporadic Parkinson's disease (PD) remain unclear, and the presence of widespread end stage pathology in late disease masks the distinction between primary or causal disease-specific events and late secondary consequences in stressed or dying cells. However, early and mid-stage Parkinson's brains (Braak stages 3 and 4) exhibit alpha-synuclein inclusions and neuronal loss along a regional gradient of severity, from unaffected-mild-moderate-severe. Here, we exploited this spatial pathological gradient to investigate the molecular drivers of sporadic PD.

METHODS

We combined high precision tissue sampling with unbiased large-scale profiling of protein expression across 9 brain regions in Braak stage 3 and 4 PD brains, and controls, and verified these results using targeted proteomic and functional analyses.

RESULTS

We demonstrate that the spatio-temporal pathology gradient in early-mid PD brains is mirrored by a biochemical gradient of a changing proteome. Importantly, we identify two key events that occur early in the disease, prior to the occurrence of alpha-synuclein inclusions and neuronal loss: (i) a metabolic switch in the utilisation of energy substrates and energy production in the brain, and (ii) perturbation of the mitochondrial redox state. These changes may contribute to the regional vulnerability of developing alpha-synuclein pathology. Later in the disease, mitochondrial function is affected more severely, whilst mitochondrial metabolism, fatty acid oxidation, and mitochondrial respiration are affected across all brain regions.

CONCLUSIONS

Our study provides an in-depth regional profile of the proteome at different stages of PD, and highlights that mitochondrial dysfunction is detectable prior to neuronal loss, and alpha-synuclein fibril deposition, suggesting that mitochondrial dysfunction is one of the key drivers of early disease.

Pathological structural conversion of α-synuclein at the mitochondria induces neuronal toxicity

Aggregation of alpha-synuclein (α-Syn) drives Parkinson's disease (PD), although the initial stages of self-assembly and structural conversion have not been directly observed inside neurons. In this study, we tracked the intracellular conformational states of α-Syn using a single-molecule Förster resonance energy transfer (smFRET) biosensor, and we show here that α-Syn converts from a monomeric state into two distinct oligomeric states in neurons in a concentration-dependent and sequence-specific manner. Three-dimensional FRET-correlative light and electron microscopy (FRET-CLEM) revealed that intracellular seeding events occur preferentially on membrane surfaces, especially at mitochondrial membranes. The mitochondrial lipid cardiolipin triggers rapid oligomerization of A53T α-Syn, and cardiolipin is sequestered within aggregating lipid-protein complexes. Mitochondrial aggregates impair complex I activity and increase mitochondrial reactive oxygen species (ROS) generation, which accelerates the oligomerization of A53T α-Syn and causes permeabilization of mitochondrial membranes and cell death. These processes were also observed in induced pluripotent stem cell (iPSC)-derived neurons harboring A53T mutations from patients with PD. Our study highlights a mechanism of de novo α-Syn oligomerization at mitochondrial membranes and subsequent neuronal toxicity.

Early constipation predicts faster dementia onset in Parkinson's disease

Constipation is a common but not a universal feature in early PD, suggesting that gut involvement is heterogeneous and may be part of a distinct PD subtype with prognostic implications. We analysed data from the Parkinson's Incidence Cohorts Collaboration, composed of incident community-based cohorts of PD patients assessed longitudinally over 8 years. Constipation was assessed with the MDS-UPDRS constipation item or a comparable categorical scale. Primary PD outcomes of interest were dementia, postural instability and death. PD patients were stratified according to constipation severity at diagnosis: none (n = 313, 67.3%), minor (n = 97, 20.9%) and major (n = 55, 11.8%). Clinical progression to all three outcomes was more rapid in those with more severe constipation at baseline (Kaplan-Meier survival analysis). Cox regression analysis, adjusting for relevant confounders, confirmed a significant relationship between constipation severity and progression to dementia, but not postural instability or death. Early constipation may predict an accelerated progression of neurodegenerative pathology.

Stress reactivity elicits a tissue-specific reduction in telomere length in aging zebrafish (Danio rerio)

Individual differences in personality are associated with variation in healthy aging. Health behaviours are often cited as the likely explanation for this association; however, an underlying biological mechanism may also exist. Accelerated leukocyte telomere shortening is implicated in multiple age-related diseases and is associated with chronic activation of the hypothalamus-pituitary-adrenal (HPA) axis, providing a link between stress-related personality differences and adverse health outcomes. However, the effects of the HPA axis are tissue specific. Thus, leukocyte telomere length may not accurately reflect telomere length in disease-relevant tissues. Here, we examined the correlation between stress reactivity and telomere length in heart and brain tissue in young (6-9 month) and aging (18 month) zebrafish. Stress reactivity was assessed by tank diving and through gene expression. Telomere length was assessed using quantitative PCR. We show that aging zebrafish have shorter telomeres in both heart and brain. Telomere length was inversely related to stress reactivity in heart but not brain of aging individuals. These data support the hypotheses that an anxious predisposition contributes to accelerated telomere shortening in heart tissue, which may have important implications for our understanding of age-related heart disease, and that stress reactivity contributes to age-related telomere shortening in a tissue-specific manner.

G protein-coupled receptor 34 in ovarian granulosa cells of cattle: changes during follicular development and potential functional implications

Abundance of G protein-coupled receptor 34 (GPR34) mRNA is greater in granulosa cells (GCs) of cystic vs normal follicles of cattle. The present experiments were designed to determine if GPR34 mRNA in granulosa cell [GC] changes during selection and growth of dominant follicles in cattle as well as to investigate the hormonal regulation of GPR34 mRNA in bovine GC in vitro. In Exp. 1, estrous cycles of nonlactating cows were synchronized and then ovariectomized on either day 3-4 or 5-6 after ovulation. GPR34 mRNA abundance in GC was 2.8- to 3.8-fold greater (P < 0.05) in small (1-5 mm) and large (≥8 mm) estrogen-inactive dominant follicles than in large estrogen-active follicles. Also, GPR34 mRNA tended to be greater (P < 0.10) in F2 than F1 follicles on day 3-4 postovulation. In Exp. 2-7, ovaries were collected at an abattoir and GC were isolated and treated in vitro. Expression of GPR34 was increased (P < 0.05) 2.2-fold by IGF1. Tumor necrosis factor (TNF)-α decreased (P < 0.05) the IGF1-induced GPR34 mRNA abundance in small-follicle GC, whereas IGF1 decreased (P < 0.05) GPR34 expression by 45% in large-follicle GC. Treatment of small-follicle GC with either IL-2, prostaglandin E2 or angiogenin decreased (P < 0.05) GPR34 expression, whereas FSH, cortisol, wingless 3A, or hedgehog proteins did not affect (P > 0.10) GPR34 expression. In Exp. 6 and 7, 2 presumed ligands of GPR34, L-a-lysophosphatidylserine (LPPS) and LPP-ethanolamine, increased (P < 0.05) GC numbers and estradiol production by 2-fold or more in small-follicle GC, and this response was only observed in IGF1-treated GC. In conclusion, GPR34 is a developmentally and hormonally regulated gene in GC, and its presumed ligands enhance IGF1-induced proliferation and steroidogenesis of bovine GC.

Changes in fibroblast growth factor 9 mRNA in granulosa and theca cells during ovarian follicular growth in dairy cattle

Fibroblast growth factor 9 (FGF9) has been suggested to act as an antidifferentiation factor in cattle by reducing steroidogenesis and increasing cell proliferation in granulosa (GC) and theca (TC) cells. The objective of this study was to characterize FGF9 mRNA abundance in GC and TC during development of dominant follicles in dairy cattle. Estrous cycles of nonlactating dairy cattle were synchronized, and ovaries were collected on either d 3 to 4 (n=8) or 5 to 6 (n=8) postovulation for GC and TC RNA extraction from small (1-5mm), medium (5.1-8mm), and large (8.1-18mm) follicles for PCR analysis. The FGF9 mRNA abundance was greater in GC than in TC. In GC, FGF9 mRNA abundance was greater in small, medium, and large estrogen-inactive [i.e., concentrations of estradiol (E2)<progesterone (P4)] follicles than in large E2-active (i.e., concentrations of E2>P4) follicles at both early (d 3-4) and late (d 5-6) growing phases of first dominant follicle. Abundance of FGF9 mRNA increased in medium-sized follicles from early to late growing phase of the dominant follicle. In TC, FGF9 mRNA abundance was greater in large E2-inactive follicles than in large E2-active follicles on d 3 to 4 postovulation; no significant differences in TC FGF9 mRNA existed among follicle types on d 5 to 6 postovulation. Correlations among levels of follicular fluid hormones and FGF9 mRNA levels revealed significant negative correlations between GC FGF9 mRNA abundance and follicular fluid E2 (r=-0.68), free IGF-1 (r=-0.63), and E2-to-P4 ratio (r=-0.58). In summary, abundance of FGF9 mRNA in GC and TC increases in medium-sized follicles during development of dominant follicles and is less in dominant E2-active than subordinate E2-inactive follicles, suggesting that FGF9 signaling could contribute to normal follicle development and steroidogenesis in dairy cattle.

Effects of Teachers' Marital Status and Child's Family's Marital Status on Teachers' Ratings of a Child

The purposes of this study were to assess whether knowledge of a child's family's marital status (divorced home/intact home/family status unknown) and/or teachers' marital status (single/divorced) would affect teachers' ratings of that child's personality traits and predicted behaviors. The study also sought to determine whether raters' marital status and knowledge of family background interacted with these teachers' ratings. The subjects were 27 married and 27 divorced teachers of preschool through Grade five. To test the hypotheses, two instruments were employed. The Personality Trait Rating Scale and the Predicted Behavior in School Scale were used by the teachers to rate behaviors of a 5-yr.-old child observed on a videotape. Knowledge of the child's family's marital status had no significant effect on teachers' ratings on either test. Teachers' own marital status had no significant effect on ratings, and no interaction was noted. Contrary to some earlier research, teachers were not biased in their ratings by knowledge of a child's family's marital status. Similarly, married teachers who had not experienced the divorce process themselves were no more positively or negatively biased in their ratings than were the divorced teachers.

A New Symbol Substitution Test for Investigating Reading Disabilities

Three symbol association subtests were constructed that involved association of words with geometric designs, words with nonsense words, and geometric designs with other designs. These tests were standardized on 457 children. In an initial study, each test was administered to 19 reading-disabled children and matched controls. Five specific score patterns were found for 15 poor readers, but only 4 controls. In a second study of 10 disabled readers, all showed one of these same five patterns. The possibility that the patterns reflect different types of cognitive dysfunction that underlie some specific reading disabilities is discussed. With further validation, the tests might prove useful in research and clinical practice with reading-disabled children.

Clinical Neurophysiology in the Schools

Criticisms of many commonly used psycho-educational tests have stimulated interest in development of more objective and culturally less biased assessment procedures. The disciplines of neuropsychology, electrophysiology and psychophysiology use procedures which could be of value in this regard. Potential contributions of each of these disciplines are discussed. Brief descriptions are given of representative assessment tools used by clinical neuropsychologists and psychophysiologists. Several approaches to computer scored measurement of electrical activity of the brain in assessment of school learning problems are described.

Aspergillus thromboembolism from a mycotic ascending aortic pseudoaneurysm

This case report describes an immune-competent patient with acute upper extremity ischemia caused by thromboembolism from an Aspergillus-infected ascending aortic pseudoaneurysm. Efforts to identify the source of an acute arterial thromboembolic occlusion should be made, and a high index of suspicion for mycotic infection should be maintained in patients with an atypical presentation, such as fevers of unknown origin. Additional measures, such as pathologic examination of thromboembolic debris, blood cultures, and positron emission tomography, should be performed to identify the etiology in these unexplained situations.

Short-term outcomes after perinatal hypoxic ischemic encephalopathy: a report from the Children's Hospitals Neonatal Consortium HIE focus group

OBJECTIVE

To characterize infants affected with perinatal hypoxic ischemic encephalopathy (HIE) who were referred to regional neonatal intensive care units (NICUs) and their related short-term outcomes.

STUDY DESIGN

This is a descriptive study evaluating the data collected prospectively in the Children's Hospital Neonatal Database, comprised of 27 regional NICUs within their associated children's hospitals. A consecutive sample of 945 referred infants born ⩾36 weeks' gestation with perinatal HIE in the first 3 days of life over approximately 3 years (2010-July 2013) were included. Maternal and infant characteristics are described. Short-term outcomes were evaluated including medical comorbidities, mortality and status of survivors at discharge.

RESULT

High relative frequencies of maternal predisposing conditions, cesarean and operative vaginal deliveries were observed. Low Apgar scores, profound metabolic acidosis, extensive resuscitation in the delivery room, clinical and electroencephalographic (EEG) seizures, abnormal EEG background and brain imaging directly correlated with the severity of HIE. Therapeutic hypothermia was provided to 85% of infants, 15% of whom were classified as having mild HIE. Electrographic seizures were observed in 26% of the infants. Rates of complications and morbidities were similar to those reported in prior clinical trials and overall mortality was 15%.

CONCLUSION

Within this large contemporary cohort of newborns with perinatal HIE, the application of therapeutic hypothermia and associated neurodiagnostic studies appear to have expanded relative to reported clinical trials. Although seizure incidence and mortality were lower compared with those reported in the trials, it is unclear whether this represented improved outcomes or therapeutic drift with the treatment of milder disease.

The Children's Hospitals Neonatal Database: an overview of patient complexity, outcomes and variation in care

The Children's Hospitals Neonatal Consortium is a multicenter collaboration of leaders from 27 regional neonatal intensive care units (NICUs) who partnered with the Children's Hospital Association to develop the Children's Hospitals Neonatal Database (CHND), launched in 2010. The purpose of this report is to provide a first summary of the population of infants cared for in these NICUs, including representative diagnoses and short-term outcomes, as well as to characterize the participating NICUs and institutions. During the first 2 1/2 years of data collection, 40910 infants were eligible. Few were born inside these hospitals (2.8%) and the median gestational age at birth was 36 weeks. Surgical intervention (32%) was common; however, mortality (5.6%) was infrequent. Initial queries into diagnosis-specific inter-center variation in care practices and short-term outcomes, including length of stay, showed striking differences. The CHND provides a contemporary, national benchmark of short-term outcomes for infants with uncommon neonatal illnesses. These data will be valuable in counseling families and for conducting observational studies, clinical trials and collaborative quality improvement initiatives.

Predicting death or tracheostomy placement in infants with severe bronchopulmonary dysplasia

OBJECTIVE

To estimate the risk of death or tracheostomy placement (D/T) in infants with severe bronchopulmonary dysplasia (sBPD) born < 32 weeks' gestation referred to regional neonatal intensive care units.

STUDY DESIGN

We conducted a retrospective cohort study in infants born < 32 weeks' gestation with sBPD in 2010-2011, using the Children's Hospital Neonatal Database. sBPD was defined as the need for FiO2 ⩾ 0.3, nasal cannula support >2 l min(-1) or positive pressure at 36 weeks' post menstrual age. The primary outcome was D/T before discharge. Predictors associated with D/T in bivariable analyses (P < 0.2) were used to develop a multivariable logistic regression equation using 80% of the cohort. This equation was validated in the remaining 20% of infants.

RESULT

Of 793 eligible patients, the mean gestational age was 26 weeks' and the median age at referral was 6.4 weeks. D/T occurred in 20% of infants. Multivariable analysis showed that later gestational age at birth, later age at referral along with pulmonary management as the primary reason for referral, mechanical ventilation at the time of referral, clinically diagnosed pulmonary hypertension, systemic corticosteroids after referral and occurrence of a bloodstream infection after referral were each associated with D/T. The model performed well with validation (area under curve 0.86, goodness-of-fit χ(2), P = 0.66).

CONCLUSION

Seven clinical variables predicted D/T in this large, contemporary cohort with sBPD. These results can be used to inform clinicians who counsel families of affected infants and to assist in the design of future prospective trials.

Effects of fibroblast growth factor 9 on steroidogenesis and control of FGFR2IIIc mRNA in porcine granulosa cells

The objectives of this study were to investigate the effects of fibroblast growth factor 9 (FGF9) on hormone-stimulated porcine granulosa cell proliferation and steroid production and to further elucidate the hormonal and developmental control of FGFR2IIIc gene expression in granulosa cells. Porcine ovaries were collected from a local slaughterhouse and granulosa cells were collected from small to medium (1 to 5 mm) follicles for 5 in vitro studies that were conducted. Cells were cultured for 48 h in 5% fetal calf serum plus 5% porcine serum and then treated with various combinations of FSH, IGF-I, FGF9, Sonic hedgehog (SHH), cortisol, PGE2, and/or wingless-type mouse mammary tumor virus integration site family member 5A (WNT5A) in serum-free medium for an additional 24 or 48 h. Medium was collected for analysis of steroid concentration via RIA, or RNA was collected for gene expression analysis of FGFR2IIIc via quantitative reverse transcription PCR. Fibroblast growth factor 9 stimulated (P < 0.05) IGF-I-induced estradiol production in the presence of FSH and testosterone. However, FGF9 had inconsistent effects on progesterone production, stimulating progesterone production in the presence of FSH and testosterone but inhibiting progesterone production in the presence of IGF-I, FSH, and testosterone. Cell numbers were increased (P < 0.05) by FGF9 in the presence of IGF-I and FSH but not in the presence of FSH and absence of IGF-I. For FGFR2IIIc mRNA studies, granulosa cells were treated with FSH, IGF-I, FGF9, SHH, cortisol, PGE2, or WNT5A. Follicle-stimulating hormone alone had no effect (P > 0.10) whereas IGF-I increased (P < 0.05) FGFR2IIIc mRNA abundance. Cortisol, PGE2, SHH, and WNT5A had no effect (P > 0.10) on FGFR2IIIc gene expression whereas FGF9 in the presence of FSH and IGF-I inhibited (P < 0.05) FGFR2IIIc gene expression. In an in vivo study, granulosa cells from large (7 to 14 mm) follicles had greater (P < 0.05) abundance of FGFR2IIIc mRNA than small (1 to 3 mm) or medium (4 to 6 mm) follicles. In conclusion, IGF-I-induced FGFR2IIIc mRNA may be a mechanism for increased responses to FGF9 in FSH plus IGF-I-treated granulosa cells. Fibroblast growth factor 9 and IGF-I may work together as amplifiers of follicular growth and granulosa cell differentiation by stimulating estradiol production and concomitantly stimulating granulosa cell growth in pigs.

Therapeutic interventions and short-term outcomes for infants with severe bronchopulmonary dysplasia born at <32 weeks' gestation

OBJECTIVE

To characterize the treatments and short-term outcomes in infants with severe bronchopulmonary dysplasia (sBPD) referred to regional neonatal intensive care units.

STUDY DESIGN

Infants born <32 weeks' gestation with sBPD were identified using the Children's Hospital Neonatal Database. Descriptive outcomes are reported.

RESULT

A total of 867 patients were eligible. On average, infants were born at 26 weeks' gestation and referred 43 days after birth. Infants frequently experienced lung injury (pneumonia: 24.1%; air leak: 9%) and received systemic corticosteroids (61%) and mechanical ventilation (median duration 37 days). Although 91% survived to discharge, the mean post-menstrual age was 47 weeks. Ongoing care such as supplemental oxygen (66%) and tracheostomy (5%) were frequently needed.

CONCLUSION

Referred infants with sBPD sustain multiple insults to lung function and development. Because affected infants have no proven, safe or efficacious therapy and endure an exceptional burden of care even after referral, urgent work is required to observe and improve their outcomes.

An analysis of the natural course of compensatory sweating following thoracoscopic sympathectomy

BACKGROUND

To evaluate the long-term results of thoracoscopic sympathectomy in the treatment of hyperhydrosis.

METHODS

Theatre log books were used to identify all patients who underwent thoracoscopic sympathectomy between 2000 and 2006. Details of pre-operative symptoms, surgical procedure and post-operative complications were collected from the patient notes. Each patient was sent a questionnaire regarding success of the procedure, compensatory sweating and overall satisfaction.

RESULTS

46 hyperhydrosis patients (34 females) age range 14-57 years. 20 patients suffered with hyperhydrosis in a combination of areas, 14 in the axillae alone, 9 palms alone and with 2 facial symptoms. There were 2 early post-operative complications, 1 haemothorax which required a chest drain and a chest infection. 3 patients required redo procedures. Of follow-up of 42 months (range 6-84), 32 (69·5%) patients reported complete dryness or a significant improvement in symptoms and 15 a substantial improvement in quality of life. However 43 patients (93%) suffered with compensatory sweating, of these 27 had to change clothes more than once daily. Compensatory sweating was graded as severe in 18 and incapacitating in 2. Of note only 5 patients noticed an improvement in the compensatory sweating over time. Only 26 (56%) would recommend thoracoscopic sympathectomy to others with hyperhydrosis.

CONCLUSION

Thoracoscopic sympathectomy is effective in the treatment of hyperhydrosis. However compensatory sweating seems unavoidable and infrequently improves with time. Patients need to be carefully counselled before committing to surgery.

Finding solutions for bird restoration and livestock management: comparing grazing exclusion levels

Riparian habitats in the western United States support high avian abundance and diversity and are important areas for livestock grazing, although grazing contributes to the degradation of riparian vegetation. Complete removal of livestock is generally the most beneficial for bird communities, but alternative management approaches allowing for seasonal livestock grazing may also increase avian habitat quality. Determining management approaches that integrate conservation priorities and human use has the potential to improve conditions for birds across many grazed landscapes. We anticipated that both the full and seasonal exclusion of cattle from riparian areas would result in the recovery of avian populations. To test this, we experimentally compared the effects of total cattle exclusion vs. seasonal usage on bird populations in the riparian areas of two creeks in the San Joaquin Valley, California, USA. Avian species richness and average abundance were measured over six years, from 2001 to 2006. In general, native avian abundance and richness increased in both full- and seasonal-exclosure areas, with increases compared to the pretreatment year for all years except 2005. Habitats that had complete cattle exclusion recovered more significantly, with 29% lower avian abundance in seasonally grazed habitats. There was no significant difference in avian richness between the two grazing treatments, although richness did increase over time. In addition to increases in native species, abundance of nonnative birds and brood parasites also increased significantly, with a greater avian abundance in the full-exclusion areas. A direct comparison with the Breeding Bird Survey (BBS), to further investigate annual avian population trends, explained the native species decline in 2005. This comparison revealed that observed trends were the effect of experimental treatment rather than a reflection of regional trends. Although the overall trends indicate that the full exclusion of livestock from riparian areas results in more abundant bird populations, seasonal exclusion is also a successful method for avian recovery. Land managers should consider both options in riparian areas, selecting full cattle removal for avian management only and seasonal cattle removal for situations where incorporating conservation and land use practices is advantageous.

Complications of transanal endoscopic microsurgery (TEMS): a prospective audit

BACKGROUND

The aim of this study was to determine the postoperative complications of Transanal Endoscopic Microsurgery (TEMS) excision of rectal lesions.

METHOD

A prospective audit of 262 consecutive TEMS procedures performed by a single surgeon between 1999 and 2008.

RESULTS

The mean age of patients was 72 years. The mean area of the lesions excised was 17.5 cm(2) with a mean diameter of 4.5 cm at a mean distance of 7.4 cm from the dentate line. There were 201 full thickness excisions, 51 partial thickness excisions and nine were mixed or unclassified. Thirty-three (13%) patients developed 41 complications. There were two (0.8%) deaths within 30 days. Pelvic sepsis occurred in seven (3%) patients and was significantly more common after excision of low lesions within 2 cm of the dentate line. Postoperative haemorrhage occurred in seven (3%) patients and was significantly less common when dissection was performed with ultrasonic dissection than with diathermy. Fourteen (5%) patients developed acute urinary retention. Four (1.5%) patients developed rectal stenosis and four (1.5%) suffered uncomplicated surgical emphysema that required no treatment.

CONCLUSIONS

Transanal endoscopic microsurgery is a safe operation with a low mortality and morbidity. Pelvic sepsis is more common after excision of lesions within 2 cm of the dentate line. Ultrasonic dissection is associated with less postoperative haemorrhage than diathermy.

The apparent temperature response of leaf respiration depends on the timescale of measurements: a study of two cold climate species

Productivity and climate models often use a constant Q10 for plant respiration, assuming tight control of respiration by temperature. We studied the temperature response of leaf respiration of two cold climate species (the Australian tree Eucalyptus pauciflora and the subantarctic megaherb Pringlea antiscorbutica, both measured in a field setting) on a short timescale (minutes) during different times within a diel course, and on a longer timescale, using diel variations in ambient temperature. There were great variations in Q10 depending on measuring day, measuring time and measuring method. When Q10 was calculated from short-term (15 min) manipulations of leaf temperature, the resulting values were usually markedly smaller than when Q10 was calculated from measurements at ambient leaf temperatures spread over a day. While for E. pauciflora, Q10 estimates decreased with rising temperature (corroborating the concept of a temperature-dependent Q10), the opposite was the case for P. antiscorbutica. Clearly, factors other than temperature co-regulate both leaf respiration rates and temperature sensitivity and contribute to diel and seasonal variation of respiration.

Antioxidant vitamin and mineral supplements for preventing age-related macular degeneration

BACKGROUND

Some observational studies have suggested that people who eat a diet rich in antioxidant vitamins (carotenoids, vitamins C and E) or minerals (selenium and zinc) may be less likely to develop age-related macular degeneration (AMD).

OBJECTIVES

The aim of this review was to examine the evidence as to whether or not taking vitamin or mineral supplements prevents the development of AMD.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) in The Cochrane Library (2007, Issue 3), MEDLINE (1966 to August 2007), SIGLE (1980 to 2005/03), EMBASE (1980 to August 2007), National Research Register (2007, Issue 3), AMED (1985 to January 2006) and PubMed (on 24 January 2006 covering last 60 days), reference lists of identified reports and the Science Citation Index. We contacted investigators and experts in the field for details of unpublished studies.

SELECTION CRITERIA

We included all randomised trials comparing an antioxidant vitamin and/or mineral supplement (alone or in combination) to control. We included only studies where supplementation had been given for at least one year.

DATA COLLECTION AND ANALYSIS

Both review authors independently extracted data and assessed trial quality. Data were pooled using a fixed-effect model.

MAIN RESULTS

Three randomised controlled trials were included in this review (23,099 people randomised). These trials investigated alpha-tocopherol and beta-carotene supplements. There was no evidence that antioxidant vitamin supplementation prevented or delayed the onset of AMD. The pooled risk ratio for any age-related maculopathy (ARM) was 1.04 (95% CI 0.92 to 1.18), for AMD (late ARM) was 1.03 (95% CI 0.74 to 1.43). Similar results were seen when the analyses were restricted to beta-carotene and alpha-tocopherol.

AUTHORS' CONCLUSIONS

There is no evidence to date that the general population should take antioxidant vitamin and mineral supplements to prevent or delay the onset of AMD. There are several large ongoing trials. People with AMD should see the related Cochrane review "Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration" written by the same author.

Relapsing polychondritis presenting as meningoencephalitis with valvular abnormality: a case report

Relapsing polychondritis is a rare rheumatologic disorder that is characterized by recurrent inflammation of selected connective tissue sites and destruction of cartilage throughout the body. We report a case of newly diagnosed relapsing polychondritis in a 40-year-old man presenting with episcleritis, deformed "cauliflower" ears, aortic regurgitation, and aseptic meningoencephalitis. Steroid therapy was instituted with good resolution of his clinical symptoms.

Surgical interventions for age-related cataract

BACKGROUND

Cataract accounts for 50% of blindness globally and remains the leading cause of visual impairment in all regions of the world, despite improvements in surgical outcomes (WHO 2005). This number is expected to rise due to an aging population and increase in life expectancy. Although cataracts are not preventable, their surgical treatment is one of the most cost-effective interventions in healthcare.

OBJECTIVES

To compare the effects of different surgical interventions for age-related cataract.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE, EMBASE up to July 2006, NRR Issue 3 2005, the reference lists of identified trials and we contacted investigators and experts in the field for details of published and unpublished trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTS).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and discrepancies were resolved by discussion. Where appropriate, risk ratios, odds ratios and weighted mean differences were summarised after assessing heterogeneity between the studies.

MAIN RESULTS

We identified 17 trials that randomised a total of 9627 people. Phacoemulsification gave a better visual outcome than extracapsular surgery but similar average cost per procedure in Europe but not in poorer countries. Extracapsular surgery with posterior chamber lens implant and ICCE with or without an anterior chamber intraocular lens (IOL) implant gave acceptable visual outcomes but extracapsular surgery had less complications. Manual small incision surgery provides better visual outcome than ECCE but slightly inferior unaided visual acuity compared to phacoemulsification.

AUTHORS' CONCLUSIONS

This review provides evidence from seven RCTs that phacoemulsification gives a better outcome than ECCE with sutures. We also found evidence that ECCE with a posterior chamber lens implant provides better visual outcome than ICCE with aphakic glasses. The long term effect of posterior capsular opacification (PCO) needs to be assessed in larger populations. The data also suggests that ICCE with an anterior chamber lens implant is an effective alternative to ICCE with aphakic glasses, with similar safety. Phacoemulsification provides the best visual outcomes but will only be accessible to the poorer countries if the cost of phacoemulsification and foldable IOLs decrease. Manual small incision cataract surgery provides early visual rehabilitation and comparable visual outcome to PHACO. It has better visual outcomes than ECCE and can be used in any clinic that is currently carrying out ECCE with IOL. Further research from developing regions are needed to compare the cost and longer term outcomes of these procedures e.g. PCO and corneal endothelial cell damage.

Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration

BACKGROUND

It has been proposed that antioxidants may prevent cellular damage in the retina by reacting with free radicals that are produced in the process of light absorption.

OBJECTIVES

The objective of this review was to assess the effects of antioxidant vitamin or mineral supplementation, or both, on the progression of age-related macular degeneration (AMD).

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2005, Issue 4); MEDLINE (1966 to January 2006); SIGLE (1980 to March 2005); EMBASE (1980 to January 2005); NRR (2005, Issue 4); AMED (1985 to January 2006); and PubMed (24 January 2006 covering last 60 days), reference lists of identified reports and the Science Citation Index. We contacted investigators and experts in the field for details of unpublished studies.

SELECTION CRITERIA

We included randomised trials comparing antioxidant vitamin or mineral supplemention (alone or in combination) to a control intervention in people with AMD.

DATA COLLECTION AND ANALYSIS

The author extracted data and assessed trial quality. Where appropriate, data were pooled using a random-effects model unless three or fewer trials were available in which case a fixed-effects model was used.

MAIN RESULTS

Eight trials were included in this review. The majority of people were randomised in one trial (AREDS in the USA) that found a beneficial effect of antioxidant (beta-carotene, vitamin C and vitamin E) and zinc supplementation on progression to advanced AMD (adjusted odds ratio 0.68, 99% confidence interval 0.49 to 0.93). People taking supplements were less likely to lose 15 or more letters of visual acuity (adjusted odds ratio 0.77, 99% confidence interval 0.58 to 1.03). Hospitalisation for genito-urinary problems was more common in people taking zinc and yellowing of skin was more common in people taking antioxidants. The other trials were, in general, small and the results were inconsistent.

AUTHORS' CONCLUSIONS

The evidence as to the effectiveness of antioxidant vitamin and mineral supplementation in halting the progression of AMD comes mainly from one large trial in the USA. The generalisability of these findings to other populations with different nutritional status is not known. Further large, well-conducted randomised controlled trials in other populations are required. Long-term harm from supplementation cannot be ruled out. Beta-carotene has been found to increase the risk of lung cancer in smokers; vitamin E has been associated with an increased risk of heart failure in people with vascular disease or diabetes.

28,000 Cases of age related macular degeneration causing visual loss in people aged 75 years and above in the United Kingdom may be attributable to smoking

BACKGROUND

Age related macular degeneration (AMD) causing visual impairment is common in older people. Previous studies have identified smoking as a risk factor for AMD. However, there is limited information for the older population in Britain.

METHODS

Population based cross sectional analytical study based in 49 practices selected to be representative of the population of Britain. Cases were people aged 75 years and above who were visually impaired (binocular acuity <6/18) as a result of AMD. Controls were people with normal vision (6/6 or better). Smoking history was ascertained using an interviewer administered questionnaire.

RESULTS

After controlling for potentially confounding factors, current smokers were twice as likely to have AMD compared to non-smokers (odds ratio 2.15, 95% CI 1.42 to 3.26). Ex-smokers were at intermediate risk (odds ratio 1.13, 0.86 to 1.47). People who stopped smoking more than 20 years previously were not at increased risk of AMD causing visual loss. Approximately 28,000 cases of AMD in older people in the United Kingdom may be attributable to smoking.

CONCLUSION

This is the largest study of the association of smoking and AMD in the British population. Smoking is associated with a twofold increased risk of developing AMD. An increased risk of AMD, which is the most commonly occurring cause of blindness in the United Kingdom, is yet another reason for people to stop smoking and governments to develop public health campaigns against this hazard.

Radiotherapy for neovascular age-related macular degeneration

BACKGROUND

Radiotherapy has been proposed as a treatment to prevent new vessel growth in people with neovascular age-related macular degeneration (AMD).

OBJECTIVES

The aim of this review was to examine the effects of radiotherapy on neovascular AMD.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group trials register) on The Cochrane Library Issue 2, 2004, MEDLINE (1966 to May 2004), EMBASE (1980 to June 2004) and LILACS (Latin American and Caribbean Health Sciences Literature Database) (May 2004). We also wrote to investigators of trials included in the review to ask if they were aware of any other studies.

SELECTION CRITERIA

We included all randomised controlled trials in which radiotherapy was compared to another treatment, sham treatment, low dosage irradiation or no treatment in people with subfoveal choroidal neovascularisation secondary to AMD.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted the data. Relative risks were combined using a random effects model. The percentage of the variability in effect estimates that was due to heterogeneity, rather than sampling error, was estimated using I2.

MAIN RESULTS

Eleven trials randomising a total of 1078 people were included in this review. All trials used a similar method of delivering the radiotherapy treatment (external beam). Dosage ranged from 7.5 to 24 Gy. Most trials found effects (not always significant) that favoured treatment. However, there was considerable inconsistency in the results between trials (I2 > 50%). As only 11 trials were included in the review and only some of these trials provided data for each outcome our ability to determine the causes of the heterogeneity between trials was limited. Subgroup analyses did not reveal any statistically significant interactions although with small numbers of trials in each subgroup (range two to four) this was not surprising. There was some indication that trials with no sham irradiation reported a greater effect of treatment as did trials with a greater percentage of participants with classic choroidal neovascularisation.

REVIEWERS' CONCLUSIONS

This review currently does not provide evidence that external beam radiotherapy is an effective treatment for neovascular AMD. If further trials are to be considered to evaluate radiotherapy in AMD then adequate masking of the control group must be considered. Given the recent evidence that most lesions are amenable to treatment with photodynamic therapy if identified at a small lesion size, trials evaluating radiotherapy against photodynamic therapy are warranted.