bluuebunny/crossref_metadata_2025 huggingface dataset:
Schools as potential vaccination venue for vaccines outside regular EPI schedule: results from a school census in Pakistan
Authors: Soofi Sajid Bashir , Haq Inam-ul , Khan M Imran , Siddiqui Muhammad Bilal , Mirani Mushtaq , Tahir Rehman , Hussain Imtiaz , Puri Mahesh K , Suhag Zamir Hussain , Khowaja Asif R , Lasi Abdul Razzaq , Clemens John D , Favorov Michael , Ochiai R Leon , Bhutta Zulfiqar A
Published: January 2012

Background

Vaccines are the most effective public health intervention. Expanded Program on Immunization (EPI) provides routine vaccination in developing countries. However, vaccines that cannot be given in EPI schedule such as typhoid fever vaccine need alternative venues. In areas where school enrolment is high, schools provide a cost effective opportunity for vaccination. Prior to start of a school-based typhoid vaccination program, interviews were conducted with staff of educational institutions in two townships of Karachi, Pakistan to collect baseline information about the school system and to plan a typhoid vaccination program. Data collection teams administered a structured questionnaire to all schools in the two townships. The administrative staff was requested information on school fee, class enrolment, past history of involvement and willingness of parents to participate in a vaccination campaign.

Results

A total of 304,836 students were enrolled in 1,096 public, private, and religious schools (Madrasahs) of the two towns. Five percent of schools refused to participate in the school census. Twenty-five percent of schools had a total enrolment of less than 100 students whereas 3% had more than 1,000 students. Health education programs were available in less than 8% of public schools, 17% of private schools, and 14% of Madrasahs. One-quarter of public schools, 41% of private schools, and 43% of Madrasahs had previously participated in a school-based vaccination campaign. The most common vaccination campaign in which schools participated was Polio eradication program. Cost of the vaccine, side effects, and parents' lack of information were highlighted as important limiting factors by school administration for school-based immunization programs. Permission from parents, appropriateness of vaccine-related information, and involvement of teachers were considered as important factors to improve participation.

Conclusions

Health education programs are not part of the regular school curriculum in developing countries including Pakistan. Many schools in the targeted townships participated in immunization activities but they were not carried out regularly. In the wake of low immunization coverage in Pakistan, schools can be used as a potential venue not only for non-EPI vaccines, but for a catch up vaccination of routine vaccines.
Estimation of shear-wave interval attenuation from mode-converted data
Authors: Shekar Bharath , Tsvankin Ilya
Published: December 2011

Interval attenuation measurements provide valuable information for reservoir characterization and lithology discrimination. We extend the attenuation layer-stripping method of Behura and Tsvankin to mode-converted (PS) waves with the goal of estimating the S-wave interval attenuation coefficient. By identifying PP and PS events with shared ray segments and applying the [Formula: see text] method, we first perform kinematic construction of pure shear (SS) events in the target layer and overburden. Then, the modified spectral-ratio method is used to compute the effective shear-wave attenuation coefficient for the target reflection. Finally, application of the dynamic version of velocity-independent layer stripping to the constructed SS reflections yields the interval S-wave attenuation coefficient in the target layer. The attenuation coefficient estimated for a range of source-receiver offsets can be inverted for the interval attenuation parameters. The method is tested on multicomponent synthetic data generated with the anisotropic reflectivity method for layered VTI (transversely isotropic with a vertical symmetry axis) and orthorhombic media.
Microseismic design studies
Authors: Zimmer Ulrich
Published: December 2011

Microseismic monitoring has become an important part of borehole completions in tight-reservoir formations. Usually, clear objectives for a microseismic survey are set prior to the data acquisition. The possibility of meeting these objectives is determined by the acquisition geometry, the target formation, the completion schedule, and only to a lesser extent, by the data quality itself. Provided is a tutorial on the content and use of prejob modeling and design studies as a tool to anticipate viewing distances, data quantity, location accuracy, event magnitudes, achievable mapping distances, expected waveforms, and noise levels. In addition, potential challenges in meeting the survey objectives can be identified and solutions to these challenges can be devised prior to the survey. For downhole surveys, this involves the evaluation of different sensor array geometries and their impact on the location accuracy in different parts of the expected model. The sensitivity of the event location on the velocity model can be estimated using an initial log-based model. Recently, the detailed characterization of the event mechanism in form of a moment tensor inversion has received increased attention. The accuracy of the inverted moment tensor depends largely on the coverage of the focal sphere, i.e., the distribution of the sensors around the event location. Based on the sensor positions, areas with high- and low-quality moment tensor inversion results can be identified prior to data acquisition through the distribution of the condition number. Depending on the survey objectives and the given constraints, the microseismic design study might show that the survey objectives cannot be met. In this case, it is possible to evaluate alternate technologies, e.g., distributed temperature sensing (DTS), ahead of the project for their potential to meet these challenges.
Memory-efficient displacement-based internal friction for wave propagation simulation
Authors: Bielak Jacobo , Karaoglu Haydar , Taborda Ricardo
Published: December 2011

The characterization of anelastic losses due to material internal friction has become increasingly important in geophysical exploration and other seismological applications, as these losses greatly affect the amplitude and dispersion of seismic waves. Anelasticity is usually specified in terms of the material’s quality factor, [Formula: see text]. Different viscoelastic models have been used to represent [Formula: see text] as a function of frequency. Most of these models are defined in terms of stresses and strains as the primary variables. Thus, in three dimensions, a separate model needs to be associated with each of the six strain components. We introduce an internal friction model that uses, instead, displacements as primary variables. For a fiber, the proposed model consists of a set of three distinct elements in parallel with different relaxation mechanisms: namely, two elements that consist of a spring and a dashpot in series (Maxwell) and a third element that consists of a spring and a dashpot in parallel (Voigt). In addition to saving memory, this formulation is particularly suitable for finite-element schemes. The model exhibits an almost constant quality factor within the frequency range of interest, with a tolerance of 5% with respect to the target [Formula: see text] value, and provides a close approximation to the variation of the phase-velocity with frequency—as has been observed in empirical data. The extension of this model to 3D anelastic problems and its use in idealized cases, such as an infinite-space, a half-space, and a layered half-space, and the comparison of results with semi-analytical reference solutions obtained from theory and previous, similar studies, corroborates the validity of the proposed model for incorporating anelastic losses in wave propagation problems.
Numerical modeling of seismicity induced by fluid injection in naturally fractured reservoirs
Authors: Zhao Xueping , Paul Young R.
Published: December 2011

The interaction between hydraulic and natural fractures is of great interest for the energy resource industry because natural fractures can significantly influence the overall geometry and effectiveness of hydraulic fractures. Microseismic monitoring provides a unique tool to monitor the evolution of fracturing around the treated rock reservoir, and seismic source mechanisms can yield information about the nature of deformation. We performed a numerical modeling study using a 2D distinct-element particle flow code ([Formula: see text]) to simulate realistic conditions and increase understanding of fracturing mechanisms in naturally fractured reservoirs, through comparisons with results of the geometry of hydraulic fractures and seismic source information (locations, magnitudes, and mechanisms) from both laboratory experiments and field observations. A suite of numerical models with fully dynamic and hydromechanical coupling was used to examine the interaction between natural and induced fractures, the effect of orientation of a preexisting fracture, the influence of differential stress, and the relationship between the fluid front, fracture tip, and induced seismicity. The numerical results qualitatively agree with the laboratory and field observations, and suggest possible mechanics for new fracture development and their interaction with a natural fracture (e.g., a tectonic fault). Therefore, the tested model could help in investigating the potential extent of induced fracturing in naturally fractured reservoirs, and in interpreting microseismic monitoring results to assess the effectiveness of a hydraulic fracturing project.
Feasibility of estimating vertical transverse isotropy from microseismic data recorded by surface monitoring arrays
Authors: Gei Davide , Eisner Leo , Suhadolc Peter
Published: December 2011

Microseismic data recorded by surface monitoring arrays can be used to estimate the effective anisotropy of the overburden and reservoir. In this study we used the inversion of picked P-wave arrival times to estimate the Thomsen parameter [Formula: see text] and the anellipticity coefficient [Formula: see text]. This inversion employs an analytic equation of P-wave traveltimes as a function of offset in homogeneous, transversely isotropic media with a vertical axis of symmetry. We considered a star-like distribution of receivers and, for this geometry, we analyzed the sensitivity of the inversion method to picking noise and to uncertainties in the P-wave vertical velocity and source depth. Long offsets, as well as a high number of receivers per line, improve the estimation of [Formula: see text] and [Formula: see text] from noisy arrival times. However, if we do not use the correct value of the P-wave vertical velocity or source depth, the long-offset may increase the inaccuracy in the estimation of the anisotropic parameters. Such inaccuracy cannot be detected from time residuals. We also applied this inversion to field data acquired during the hydraulic fracturing of a gas shale reservoir and compared the results with the anisotropic parameters estimated from synthetic arrival times computed for an isotropic layered medium. The effective anisotropy from the inversion of the field data cannot be explained by layering only and is partially due to the intrinsic anisotropy of the reservoir and/or overburden. This study emphasizes the importance of using accurate values of the vertical velocity and source depth in the P-wave arrival time inversion for estimating anisotropic parameters from passive seismic data.
Modeling 3D porosity and permeability from GPR data in the Ellenburger Dolomite, central Texas
Authors: Harbi Hussein , McMechan George A.
Published: December 2011

Three-dimensional porosity and permeability were modeled in an Ellenburger carbonate reservoir analog from 2D crosshole and 3D surface survey ground-penetrating radar (GPR) data. Two-dimensional GPR crosshole velocity tomography, 3D migration of the GPR surface data, and porosity and permeability calibration to GPR attributes results in 3D porosity and permeability predictions that provide a consistent model of the paleocave structures and facies distributions. Picking the maximum instantaneous amplitude of the direct arrival wavelet for velocity tomography reduces uncertainties caused by a low signal-to-noise ratio, uncorrelated noise, and the interference between reflections and critical refractions at the earth/air interface. The GPR velocity is anisotropic with an average vertical to horizontal velocity ratio of 0.93, which is attributed to the dominance of the relatively horizontal orientation of the maximum porosity and permeability. Porosity and permeability trends are influenced by regional northeast-southwest and northwest-southeast striking conjugate fractures associated with the Pennsylvanian Ouachita orogeny and breccia facies generated by three episodes of burial and the resulting paleocave collapses. At depths [Formula: see text] from the present surface, large brecciated dolomite and limestone blocks have low porosity and low permeability. Between a depth of [Formula: see text] and [Formula: see text] irregular fracture orientations and distributions associated with collapse breccias have a higher average porosity and permeability. A deeper zone ([Formula: see text] to [Formula: see text] in depth), has intermediate permeability and porosity. Porosity and permeability could not be calibrated in open voids. Thus, the predictions are applicable to the core-scale to which they were calibrated, but are lower bounds for the whole volume, which contains breccias, karst, and fractures that increase both porosity and permeability at larger scales.
Positive and Negative Allosteric Modulators Promote Biased Signaling at the Calcium-Sensing Receptor
Authors: Davey Anna E. , Leach Katie , Valant Celine , Conigrave Arthur D. , Sexton Patrick M. , Christopoulos Arthur
Published: December 2011

The calcium-sensing receptor (CaSR) is a G protein-coupled receptor whose function can be allosterically modulated in a positive or negative manner by calcimimetics or calcilytics, respectively. Indeed, the second-generation calcimimetic, cinacalcet, has proven clinically useful in the treatment of chronic kidney disease patients with secondary hyperparathyroidism but is not widely used in earlier stages of renal disease due to the potential to predispose such patients to hypocalcaemia and hyperphosphatemia. The development of a biased CaSR ligand that is more selective for specific signaling pathway(s) leading only to beneficial effects may overcome this limitation. The detection of such stimulus-bias at a G protein-coupled receptor requires investigation across multiple signaling pathways and the development of methods to quantify the effects of allosteric ligands on orthosteric ligand affinity and cooperativity at each pathway. In the current study, we determined the effects of the calcimimetics, NPS-R568 or cinacalcet, and the calcilytic, NPS-2143, on Cao2+-mediated intracellular Ca2+ mobilization, ERK1/2 phosphorylation, and plasma membrane ruffling in a stably transfected human embryonic kidney 293-TREx c-myc-CaSR cell line and applied a novel analytical model to quantify these modulator effects. We present quantitative evidence for the generation of stimulus bias by both positive and negative allosteric modulators of the CaSR, manifested as greater allosteric modulation of intracellular Ca2+ mobilization relative to ERK1/2 phosphorylation, and a higher affinity of the modulators for the state of the CaSR mediating plasma membrane ruffling relative to the other two pathways. Our findings provide the first evidence that an allosteric modulator used in clinical practice exhibits stimulus bias.
Perinatal Iron Deficiency Combined with a High-Fat Diet Causes Obesity and Cardiovascular Dysregulation
Authors: Bourque Stephane L. , Komolova Marina , McCabe Kristin , Adams Michael A. , Nakatsu Kanji
Published: December 2011

Consumption of a high-fat Western diet (WD) and the resultant obesity is linked to a number of chronic pathologies, including cardiovascular dysregulation. The purpose of the present study was to determine whether perinatal iron deficiency (PID) added to the consumption of a WD would precipitate an obese phenotype with exacerbated metabolic and cardiovascular outcomes in adult offspring. Female Sprague Dawley rats were fed either a control (225 mg/kg Fe) or an iron-restricted diet (3–10 mg/kg Fe) prior to and throughout gestation. At birth, all dams were fed an iron-replete diet. At weaning, offspring were fed a normal diet or WD for up to 21 wk. Hemodynamics and locomotor activity were assessed by radiotelemetry starting at 15 wk of age. Iron restriction during pregnancy caused severe anemia in dams and offspring, resulting in 15% lower birth weights in the offspring. PID offspring fed the WD had greater caloric intake and exhibited reduced locomotor activity compared with their normal diet-fed littermates; no such effects were observed in normal iron control offspring. Despite having a similar effect on serum lipid profiles, consumption of the WD had a greater impact on body weight in the PID group, and this weight gain was due largely to visceral adipose tissue accumulation. A significant correlation between visceral adipose tissue weight and mean arterial pressure was observed in the PID offspring but not in controls. These observations demonstrate that PID predisposes offspring to an enhanced response to WD characterized by increased fat accumulation and cardiovascular dysregulation.
Photoperiod Regulates Vitamin A and Wnt/β-Catenin Signaling in F344 Rats
Authors: Helfer Gisela , Ross Alexander W. , Russell Laura , Thomson Lynn M. , Shearer Kirsty D. , Goodman Timothy H. , McCaffery Peter J. , Morgan Peter J.
Published: December 2011

In seasonal mammals, growth, energy balance, and reproductive status are regulated by the neuroendocrine effects of photoperiod. Thyroid hormone (TH) is a key player in this response in a number of species. A neuroendocrine role for the nutritional factor vitamin A has not been considered, although its metabolic product retinoic acid (RA) regulates transcription via the same nuclear receptor family as TH. We hypothesized that vitamin A/RA plays a role in the neuroendocrine hypothalamus alongside TH signaling. Using a reporter assay to measure RA activity, we demonstrate that RA activity levels in the hypothalamus of photoperiod-sensitive F344 rats are reduced in short-day relative to long-day conditions. These lower RA activity levels can be explained by reduced expression of a whole network of RA signaling genes in the ependymal cells around the third ventricle and in the arcuate nucleus of the hypothalamus. These include genes required for uptake (Ttr, Stra6, and Crbp1), synthesis (Raldh1), receptor response (RAR), and ligand clearance (Crapb1 and Cyp26B1). Using melatonin injections into long-day rats, we show that the probable trigger of the fall in RA is melatonin. Surprisingly we also found RPE65 expression in the mammalian hypothalamus for the first time. Similar to RA signaling genes, members of the Wnt/β-catenin pathway and NMU and its receptor NMUR2 are also under photoperiodic control. Our data provide strong evidence for a novel endocrine axis, involving the nutrient vitamin A regulated by photoperiod and melatonin and suggest a role for several new players in the photoperiodic neuroendocrine response.
Update in the CNS Response to Hypoglycemia
Authors: McCrimmon Rory J.
Published: January 2012

Hypoglycemia remains a major clinical issue in the management of people with type 1 and type 2 diabetes. Research in basic science is only beginning to unravel the mechanisms that: 1) underpin the detection of hypoglycemia and initiation of a counterregulatory defense response; and 2) contribute to the development of defective counterregulation in both type 1 and type 2 diabetes, particularly after prior exposure to repeated hypoglycemia. In animal studies, the central nervous system has emerged as key to these processes. However, bench-based research needs to be translated through studies in human subjects as a first step to the future development of clinical intervention. This Update reviews studies published in the last 2 yr that examined the central nervous system effects of hypoglycemia in human subjects, largely through neuroimaging techniques, and compares these data with those obtained from animal studies and the implications for future therapies. Based on these studies, it is increasingly clear that our understanding of how the brain responds and adapts to recurrent hypoglycemia remains very limited. Current therapies have provided little evidence that they can prevent severe hypoglycemia or improve hypoglycemia awareness in type 1 diabetes. There remains an urgent need to increase our understanding of how and why defective counterregulation develops in type 1 diabetes in order for novel therapeutic interventions to be developed and tested.
A taste of TGFβ in Tuscany
Authors: Hata Akiko , Brivanlou Ali H.
Published: January 2012

The recent FASEB Summer Research Conference entitled ‘The TGFβ Superfamily: Signaling in Development and Disease’ was held in August, 2011 in the spectacular setting of Il Ciocco, Lucca, amidst the olive trees in Tuscany, Italy. The organizers assembled an amazing forum, which included 53 speakers and 67 poster presentations from laboratories around the world, to showcase recent advances made in our understanding of the transforming growth factor-β (TGFβ) signaling pathway.
Enhancing Cognitive Functioning: Medium-Term Effects of a Health and Family Planning Program in Matlab
Authors: Barham Tania
Published: January 2012

It is believed that early life circumstances are crucial to success later in life. Yet causal evidence that the impacts of early childhood health interventions continue into late childhood and adolescence is sparse. This paper exploits a quasi-random placement of the Matlab Maternal and Child Health and Family Planning Program in Bangladesh to determine whether children eligible for child health interventions in early childhood had better cognitive functioning at ages 8–14. I find a program effect of 0.39 standard deviations on cognitive functioning and similar effects for height and educational attainment (JEL I15, I18, J13, J18, O15).
The impact of surgeon-based ultrasonography for parathyroid disease on a British endocrine surgical practice
Authors: Aspinall SR , Nicholson S , Bliss RD , Lennard TWJ
Published: December 2011

INTRODUCTION

Surgeon-based ultrasonography (SUS) for parathyroid disease has not been widely adopted by British endocrine surgeons despite reports worldwide of accuracy in parathyroid localisation equivalent or superior to radiology-based ultrasonography (RUS). The aim of this study was to determine whether SUS might benefit parathyroid surgical practice in a British endocrine unit.

METHODS

Following an audit to establish the accuracy of RUS and technetium sestamibi (MIBI) in 54 patients, the accuracy of parathyroid localisation by SUS and RUS was compared prospectively with operative findings in 65 patients undergoing surgery for primary hyperparathyroidism (pHPT).

RESULTS

The sensitivity of RUS (40%) was below and MIBI (57%) was within the range of published results in the audit phase. The sensitivity (64%), negative predictive value (86%) and accuracy (86%) of SUS were significantly greater than RUS (37%, 77% and 78% respectively). SUS significantly increased the concordance of parathyroid localisation with MIBI (58% versus 32% with RUS).

CONCLUSIONS

SUS improves parathyroid localisation in a British endocrine surgical practice. It is a useful adjunct to parathyroid practice, particularly in centres without a dedicated parathyroid radiologist, and enables more patients with pHPT to benefit from minimally invasive surgery.
Accuracy of prognostic scores in decision making and predicting outcomes in metastatic spine disease
Authors: Majeed H , Kumar S , Bommireddy R , Klezl Z , Calthorpe D
Published: December 2011

INTRODUCTION

Management of metastatic spinal disease has changed significantly over the last few years. Different prognostic scores are used in clinical practice for predicting survival. The aim of this study was to assess the accuracy of prognostic scores and the role of delayed presentation in predicting the outcome in patients with metastatic spine disease.

METHODS

Retrospectively, four years of data were collected (2007–2010). Medical records review included type of tumour, duration of symptoms, expected survival and functional status. The Karnofsky performance score was used for functional assessment. Modified Tokuhashi and Tomita scores were used for survival prediction.

RESULTS

A total of 55 patients who underwent surgical stabilisation were reviewed. The mean age was 63 years (range: 32–87 years). The main primary sources of tumours included myeloma, breast cancer, lymphoma, lung cancer, renal cell cancer and prostate cancer. Of the cases studied, 29 patients had posterior instrumented stabilisation alone, 10 patients had an anterior procedure alone and 16 patients (with an expected survival of more than one year) had both anterior and posterior procedures performed. Twenty-three patients presented with spinal cord compression. The mean follow-up duration was 9 months (range: 1–39 months). Patients who were treated within one week of referral survived longer than anticipated. Patients were divided into three groups based on their expected survival. Actual survival was better in all three groups after surgery. Discrepancies in scores were prominent in patients with myeloma, breast and prostate cancers. Functional outcome was better in patients under 65 years of age.

CONCLUSIONS

The prognostic scoring systems are not uniformly effective in all types of primary tumours. However, they are useful in decision making for surgical intervention, taking other factors into account, in particular the age of the patient, the type and stage of the primary tumour and general health.
Pacemaker placement and shoulder surgery: is there a risk?
Authors: Ahrens PM , Siddiqui NA , Rakhit RD
Published: December 2011

INTRODUCTION

Surgery to the anterior aspect of the shoulder is performed by many surgical specialties but the techniques used by our cardiology colleagues for insertion of cardiac pacemaker wires are often not appreciated by the surgical community. The deltopectoral approach has been used for open pacemaker wire insertion for many years by cardiologists. METHODS We surveyed a group of subspecialty shoulder surgeons as well as orthopaedic trainees to see if this approach for pacemakers is well recognised. We tried to assess what level of knowledge exists regarding pacemaker placement in general as well as specific risks.

RESULTS

There appears to be a paucity of knowledge regarding pacemaker placement and related patient safety issues in both surveyed groups. There was no difference between the two groups, suggesting that the level of knowledge does not increase with experience and specialisation.

CONCLUSIONS

There is the potential to cause harm to patients if the insertion site and type of device is not identified before commencing surgery in this region and steps must be taken to minimise any intra-operative risk. There is a risk from direct injury to the pacemaker and/or leads as well as the hazards of using diathermy in close proximity to a pacemaker. There must be more widespread dissemination of this information in order to minimise risks to patients with pacemakers in situ.
Health-related quality of life, surgical and aesthetic outcomes following microvascular free flap reconstructions: an 8-year institutional review
Authors: Dolan RT , Butler JS , Murphy SM , Cronin KJ
Published: December 2011

INTRODUCTION

Microvascular free flap reconstruction has revolutionised the reconstruction of complex defects of traumatic, oncological, congenital and infectious aetiologies. Complications of microvascular free flap procedures impact negatively on patient post-operative course and outcome.

METHODS

We performed a retrospective analysis of 102 consecutive patients undergoing 108 free flap procedures at a tertiary referral centre over an 8-year period. Logistic regression analysis was used to identify factors pRedictive of free flap complications. Health-related quality of life (HRQoL) and aesthetic outcomes were assessed using the Short Form 36 questionnaire and a satisfaction visual analogue scale respectively.

RESULTS

In total, 108 free tissue transfers were performed; 23% were fasciocutaneous free flaps, 69% musculocutaneous and 8% osteoseptocutaneous. The overall flap success rate was 92.6%. Over a third of patients (34.3%) had flap-related complications ranging from minor wound dehiscence to total flap loss. ASA (American Society of Anesthesiologists) grade ≥2 (OR: 16.9, 95% CI: 15.3–18.1, p<0.009), history of smoking (OR: 6.1, 95% CI: 5.5–7.2, p<0.049), body mass index ≥25kg/ m2 (OR: 21.3, 95% CI: 20.8–22.1, p<0.003), low albumin (odds ratio [OR]: 2.2, 95% confidence interval [CI]: 1.2–3.9, p<0.003) and peripheral vascular disease (OR: 6.9, 95% CI: 5.9–7.5, p<0.036) were identified as factors independently predictive of free flap complications.

CONCLUSIONS

Patients undergoing uncomplicated free flap surgery and those reporting superior post-operative flap aesthesis have higher HRQoL scores. Microvascular free tissue transfer has revolutionised our approach to the reconstruction of complex defects, providing a safe, reliable procedure to restore functionality and quality of life for patients.
Acute spontaneous scrotal haematoma presenting with haemorrhagic shock: a case report
Authors: Burnand K , Viswanath S , Kumar V , Chitale S
Published: December 2011

We report an unusual case of acute spontaneous scrotal haematoma presenting with haemorrhagic shock requiring resuscitation.
Infection of laparoscopically inserted inguinal hernia repair mesh following subsequent emergency open surgery: a report of two cases
Authors: Panagiotopoulou IG , Richardson C , Gurunathan-Mani S , Lagattolla NRF
Published: December 2011

We present two cases of laparoscopically inserted mesh for inguinal hernia repair that became infected following emergency open bowel surgery. We believe that there is an increased risk of infection due to the larger size of mesh used in the laparoscopic repair but also due to the patient not volunteering the information because of the minimally invasive nature of the procedure.
Liposarcoma of the spermatic cord: a report of two cases
Authors: Tan CJ , Dasari BVM , Smyth J , Brown RJ
Published: December 2011

Liposarcomas of the spermatic cord are unusual and rarely reported in the literature. These tumours can sometimes be mistaken for the common scrotal swellings such as hydrocoeles and hernias. Careful clinical and radiological examination will help in appropriate preoperative planning and surgery by an experienced surgical team. We report our experience of two cases of such scrotal swellings.
Traumatic plastic deformation of the tibia: case report and literature review
Authors: Dhillon PS , Currall V , Shannon MN
Published: December 2011

Plastic deformation refers to the deformation of a bone, without fracture of its cortices, that persists once the deforming force has been removed. It is not a common condition but is seen more frequently in children than in adults. Of the cases published, there have been only three previous reports of tibial involvement, with the forearm being the most commonly affected site. We describe the case of a 10-year-old girl who, after falling down a slope, came to a sudden stop when her right foot hit a rock. This resulted in a fracture of the fibula and bowing of the tibia. We discuss the dilemmas faced in treatment and recommend regular follow up until the patient reaches skeletal maturity.
An acute groin lump: surgical exploration is not always the best option
Authors: Davey PT , Byrnes C
Published: December 2011

This is a case of a very unusual cause of an acute groin lump in a 71-year-old woman that was presumed initially to either be an incisional or inguinal hernia. However, with subsequent computed tomography it was shown to be thrombophlebitis of collateral vessels secondary to a previous deep vein thrombosis. This case demonstrates how surgical exploration of acute groin lumps is not without its dangers.
Spontaneous subcutaneous emphysema associated with mephedrone usage
Authors: Maan ZN , D’Souza AR
Published: December 2011

Subcutaneous emphysema in the head and neck is a rare condition, normally caused by major underlying injury to the airway or gastrointestinal tract. We report a non-traumatic occurrence of spontaneous cervical subcutaneous emphysema in a 30-year-old man who had been snorting mephedrone. The patient made an uneventful recovery, being managed conservatively, and did not require airway support. The occurrence of spontaneous cervical emphysema associated with snorting mephedrone has not been previously described in the literature.
Novel surgical reconstruction of a mycotic abdominal aortic aneurysm using cryopreserved femoral arterial allograft from the NHS tissue bank: a new resource for UK vascular surgeons
Authors: Abbas K , Davies J , Kabir I , Ahmad M , Baroni ML , Cavanagh SP
Published: December 2011

The treatment of mycotic abdominal aortic aneurysms remains a significant surgical challenge associated with significant morbidity and mortality. In the following case report, we describe our successful management of a patient with a mycotic abdominal aortic aneurysm using two cryopreserved superficial femoral artery allografts (available from the UK NHS tissue bank) to create a Y-shaped allograft to permit immediate aortic reconstruction after surgical debridement. To our knowledge, this is the first time such a reconstruction has been reported in the literature.
Benign biliary papillomatosis in a patient with a choledochal cyst presenting as haemobilia: a case report
Authors: Sen I , Raju RS , Vyas FL , Eapen A , Sitaram V
Published: December 2011

Biliary papillomatosis is a rare condition usually detected on imaging or postoperative histopathology. It may be asymptomatic or present with features of cholangitis. We report the management of a patient presenting with haemobilia.
Outcomes in the repair of pilonidal sinus disease excision wounds using a parasacral perforator flap
Authors: Venus MR , Titley OG
Published: December 2011

INTRODUCTION

The ideal treatment for pilonidal sinus disease has yet to be defined. There are many approaches described in the literature.

METHODS

Thirty-five consecutive patients who underwent wide excision of pilonidal sinus disease had the wound repaired using a parasacral perforator flap. Outcomes were assessed by case notes analysis and follow-up telephone and postal questionnaires.

RESULTS

There were ten minor complications including six minor wound edge dehiscences. There were two ischaemic complications, with one flap loss. There were 3 recurrences of pilonidal disease at a mean follow-up of 33 months, giving a 5-year recurrence free rate of 86%. Of the patients questioned, all would recommend the procedure to someone else despite 69% being dissatisfied with the cosmetic outcome.

CONCLUSIONS

This series indicates that the parasacral perforator flap technique is able to repair pilonidal sinus excision wounds successfully with minimal morbidity and a low recurrence rate at a mean of follow-up of 33 months. The study suggests that it may be a technique best reserved for recurrent cases of pilonidal sinus disease. Patients feel the procedure is successful despite reservations regarding the cosmetic outcome.
Trace element speciation in food: State of the art of analytical techniques and methods
Authors: Bou Khouzam Rola , Szpunar Joanna , Holeman Michel , Lobinski Ryszard
Published: January 2012

Some elements in food are notoriously toxic, whereas others are considered essential for human health. Information on the exact chemical form in which an element is present in food is of paramount importance to determine the safety and nutritional quality of food. This critical review discusses the state of the art of analytical approaches to speciation of trace elements in food products. The topics addressed include (i) responding to regulations concerning some toxic elements (As, Hg, Sn); (ii) quality control of food and feed supplements; and (iii) characterization, in terms of element speciation, of nutritional plants (natural and genetically modified) and food supplements produced by biotechnology. The maturity of analytical techniques allowing the determination of individual well-defined metal species is highlighted. On the other hand, the recent developments of multidimensional hyphenated techniques and the democratization of electrospray high-resolution mass spectrometry (Orbitrap) start permitting fine characterization of element speciation in natural products.
Methylmercury in rice (Oryza sativa L.) grown from the Xunyang Hg mining area, Shaanxi province, northwestern China
Authors: Qiu Guangle , Feng Xinbin , Meng Bo , Wang Xun
Published: January 2012

Mercury (Hg) is a global pollutant and can transform into methylmercury (MeHg), a highly toxic and bioaccumulative organic form. Recent surveys showed that rice (Oryza sativa L.) rather than fish is the main source of human MeHg exposure in Hg mining and retorting regions in Guizhou province, southwestern China, where rice is a traditional staple food. Here we report that MeHg in rice grown at an active Hg mining and retorting region in Shaanxi province, northwestern China, characterized with different climate compared to Guizhou, contained levels up to 240 μg kg–1 MeHg in bran, 78 μg kg–1 MeHg in polished rice, and 30 μg kg–1 MeHg in hull, respectively. Although the polishing process may reduce MeHg content, the mass balance calculation showed that greater than 50 % of total MeHg mass can be observed in white rice (polished rice). The ongoing Hg retorting activities, which account for the high levels of ambient air Hg, result in high levels of MeHg in rice grains. Our results further demonstrate that the accumulation of MeHg is a common feature of rice.
On the structure of textual and visual dissertations
Authors: HAZEL PAUL , DAVIES MARY , RILEY HOWARD
Published: January 2012

This article looks at issues surrounding the academic dissertation within the particular context of the Art and Design school. To begin with, questions of objectivity and authorial voice are examined, suggesting that current practice does little to foster student identity. A discourse
framework is then established largely based on the work of Bruner, with exposition and narrative posited as the primary problem-solving modes. This discursive framework is then transposed into the visual domain, where several possible discourse structures are suggested. A case study is offered
that highlights the benefits that can be gained from the use of a visual dissertation. In the conclusion we argue for educators to consider these alternative modes of discourse.
Among B-Type Cyclins Only CLB5 and CLB6 Promote Premeiotic S Phase in Saccharomyces cerevisiae
Authors: DeCesare James M , Stuart David T
Published: December 2011

The Saccharomyces cerevisiae cyclin Clb5 is required for premeiotic S phase, meiotic recombination, and successful progression through meiosis. Clb5 is not essential for mitotic proliferation because Clb1–Clb4 can support DNA replication in clb5clb6 mutants. Clb1, Clb3, and Clb4 accumulate in clb5clb6 cells during meiotic differentiation yet fail to promote premeiotic DNA replication. When expressed under the regulation of the CLB5 promoter, Clb1 and Clb3 accumulate and are active in the early stages of meiotic differentiation but cannot induce premeiotic DNA replication, suggesting that they do not target Cdk1 to the necessary substrates. The Clb5 hydrophobic patch (HP) residues are important for Clb5 function but this motif alone does not provide the specificity required for Clb5 to induce premeiotic S phase. Domain exchange experiments demonstrated that the amino terminus of Clb5 when fused to Clb3 confers upon Clb3 the ability to induce premeiotic S phase. Chimeric cyclins containing smaller regions of the Clb5 amino terminus displayed reduced ability to activate premeiotic DNA replication despite being more abundant and having greater associated histone H1 kinase activity than endogenous Clb5. These observations suggest that Clb5 has a unique ability to trigger premeiotic S phase and that the amino-terminal region of Clb5 contributes to its specificity and regulates the functions performed by the cyclin–Cdk complex.
A Novel Approach for Directing Transgene Expression in Drosophila: T2A-Gal4 In-Frame Fusion
Authors: Diao Fengqiu , White Benjamin H
Published: December 2011

In Drosophila, the Gal4-UAS system permits a transgene to be expressed in the same pattern as a gene of interest by placing the Gal4 transcription factor under control of the gene’s DNA regulatory elements. If these regulatory elements are not known, however, expression of Gal4 in the desired pattern may be difficult or impossible. To solve this problem, we have developed a method for co-expressing Gal4 with the endogenous gene by exploiting the “ribosomal skipping” mechanism of the viral T2A peptide. This method requires explicit knowledge only of the endogenous gene’s open reading frame and not its regulatory elements.
The Dynamics of HIV-1 Adaptation in Early Infection
Authors: da Silva Jack
Published: December 2011

Human immunodeficiency virus type 1 (HIV-1) undergoes a severe population bottleneck during sexual transmission and yet adapts extremely rapidly to the earliest immune responses. The bottleneck has been inferred to typically consist of a single genome, and typically eight amino acid mutations in viral proteins spread to fixation by the end of the early chronic phase of infection in response to selection by CD8+ T cells. Stochastic simulation was used to examine the effects of the transmission bottleneck and of potential interference among spreading immune-escape mutations on the adaptive dynamics of the virus in early infection. If major viral population genetic parameters are assigned realistic values that permit rapid adaptive evolution, then a bottleneck of a single genome is not inconsistent with the observed pattern of adaptive fixations. One requirement is strong selection by CD8+ T cells that decreases over time. Such selection may reduce effective population sizes at linked loci through genetic hitchhiking. However, this effect is predicted to be minor in early infection because the transmission bottleneck reduces the effective population size to such an extent that the resulting strong selection and weak mutation cause beneficial mutations to fix sequentially and thus avoid interference.
Extended Linkage Disequilibrium in Noncoding Regions in a Conifer, Cryptomeria japonica
Authors: Moritsuka Etsuko , Hisataka Yosuke , Tamura Miho , Uchiyama Kentaro , Watanabe Atsushi , Tsumura Yoshihiko , Tachida Hidenori
Published: December 2011

We measured linkage disequilibrium in mostly noncoding regions of Cryptomeria japonica, a conifer belonging to Cupressaceae. Linkage disequilibrium was extensive and did not decay even at a distance of 100 kb. The average estimate of the population recombination rate per base pair was 1.55 × 10−5 and was <1/70 of that in the coding regions. We discuss the impact of low recombination rates in a large part of the genome on association studies.
Notch Signaling Is Antagonized by SAO-1, a Novel GYF-Domain Protein That Interacts with the E3 Ubiquitin Ligase SEL-10 in Caenorhabditis elegans
Authors: Hale Valerie A , Guiney Evan L , Goldberg Lindsey Y , Haduong Josephine H , Kwartler Callie S , Scangos Katherine W , Goutte Caroline
Published: December 2011

Notch signaling pathways can be regulated through a variety of cellular mechanisms, and genetically compromised systems provide useful platforms from which to search for the responsible modulators. The Caenorhabditis elegans gene aph-1 encodes a component of γ-secretase, which is essential for Notch signaling events throughout development. By looking for suppressors of the incompletely penetrant aph-1(zu147) mutation, we identify a new gene, sao-1 (suppressor of aph-one), that negatively regulates aph-1(zu147) activity in the early embryo. The sao-1 gene encodes a novel protein that contains a GYF protein–protein interaction domain and interacts specifically with SEL-10, an Fbw7 component of SCF E3 ubiquitin ligases. We demonstrate that the embryonic lethality of aph-1(zu147) mutants can be suppressed by removing sao-1 activity or by mutations that disrupt the SAO-1–SEL-10 protein interaction. Decreased sao-1 activity also influences Notch signaling events when they are compromised at different molecular steps of the pathway, such as at the level of the Notch receptor GLP-1 or the downstream transcription factor LAG-1. Combined analysis of the SAO-1–SEL-10 protein interaction and comparisons of sao-1 and sel-10 genetic interactions suggest a possible role for SAO-1 as an accessory protein that participates with SEL-10 in downregulation of Notch signaling. This work provides the first mutant analysis of a GYF-domain protein in either C. elegans or Drosophila and introduces a new type of Fbw7-interacting protein that acts in a subset of Fbw7 functions.
A Simple Method for Finding Explicit Analytic Transition Densities of Diffusion Processes with General Diploid Selection
Authors: Song Yun S , Steinrücken Matthias
Published: December 2011

The transition density function of the Wright–Fisher diffusion describes the evolution of population-wide allele frequencies over time. This function has important practical applications in population genetics, but finding an explicit formula under a general diploid selection model has remained a difficult open problem. In this article, we develop a new computational method to tackle this classic problem. Specifically, our method explicitly finds the eigenvalues and eigenfunctions of the diffusion generator associated with the Wright–Fisher diffusion with recurrent mutation and arbitrary diploid selection, thus allowing one to obtain an accurate spectral representation of the transition density function. Simplicity is one of the appealing features of our approach. Although our derivation involves somewhat advanced mathematical concepts, the resulting algorithm is quite simple and efficient, only involving standard linear algebra. Furthermore, unlike previous approaches based on perturbation, which is applicable only when the population-scaled selection coefficient is small, our method is nonperturbative and is valid for a broad range of parameter values. As a by-product of our work, we obtain the rate of convergence to the stationary distribution under mutation–selection balance.
Core Concepts: Chromosome Aneuploidies
Authors: Crotwell Patricia L. , Hoyme H. Eugene
Published: December 2011

Aneuploidy, or deviation from the diploid human chromosome complement of 46, may have physical effects ranging from mild or undetectable, as in a male infant with 47 chromosomes including an additional Y chromosome, to severe, as occurs in infants with an additional chromosome 13 or 18. We discuss the autosomal (13, 18, and 21) and sex chromosome (X, Y) aneuploidies that can be expected in the neonatal health care setting, including clinical signs and symptoms that may be indications for further study. We review appropriate diagnostic testing including chromosome, fluorescent in situ hybridization, and microarray comparative genomic hybridization studies, indicating where parental follow-up studies are necessary to provide accurate recurrence risk counseling. For each aneuploid condition that is likely to be encountered in a living infant, we review appropriate clinical management strategies. Suggested readings and family resources are provided for the aneuploidies that are commonly observed in the newborn, and the reader is directed to additional resources for partial aneuploidies, which are beyond the scope of this review.