Magnetic diagnostics for equilibrium reconstruction and realtime plasma control in NSTX-Upgrade

This paper describes aspects of magnetic diagnostics for realtime control in National Spherical Torus Experiment-Upgrade (NSTX-U). The sensor arrangement on the upgraded center column is described. New analog and digital circuitry for processing the plasma current Rogowski data are presented. An improved algorithm for estimating the plasma vertical velocity for feedback control is presented.

The incidence of burns among sex-trafficking victims in India

Sex trafficking remains a flagrant violation of human rights, creating many public health concerns. During the initiation period, these victims experience acts of violence including gang rapes, subjecting them to traumatic injuries that include burns. Furthermore, lack of access to health care, particularly surgical, keeps them from receiving treatment for these functionally debilitating contractures caused by burns. This piece provides an overview of burns among sex-trafficked victims in India and the efforts by Cents of Relief to address the associated surgical burden of disease.

Impact of intracameral cefuroxime on the incidence of postoperative endophthalmitis following cataract surgery in Ireland

BACKGROUND

Postoperative endophthalmitis (PE) is a rare complication of cataract surgery, but carries a significant risk of blindness. The European Society of Cataract and Refractive Surgeons published a landmark study in 2007 that revealed the use of intracameral cefuroxime as prophylaxis against endophthalmitis reduced its incidence by fivefold. Since the publication of these results, the use of intracameral cefuroxime in cataract surgery has become a standard practice in many institutions, including our own.

AIM

To identify the incidence rate of PE among patients undergoing cataract surgery over the 4-year period following the introduction of prophylactic intracameral cefuroxime for cataract surgery.

METHODS

A retrospective case note review of all cases of postoperative endophthalmitis that occurred between 2007 and 2011 was performed. Our results were compared with an earlier report on PE incidence rates from our institution that was conducted prior to the introduction of intracameral cefuroxime and published in 2001.

RESULTS

There were five reported cases of endophthalmitis from 2007 to 2011 from a total of 8,239 cataract procedures, giving an incidence rate of 0.06%. This compares with an incidence rate of 0.49% in the earlier study prior to the introduction of intracameral cefuroxime and represents an eightfold reduction in the incidence of PE at our hospital. Of the five cases, three were confirmed on culture and sensitivity (two of which were due to Coagulase negative staphylococci and one due to Pseudomonas aeruginosa).

CONCLUSION

The incidence of postoperative endophthalmitis has reduced by approximately eightfold since the introduction of intracameral cefuroxime following cataract surgery at our hospital in 2007. This study strongly supports the use of intracameral cefuroxime as prophylaxis against endophthalmitis in all cataract surgical cases.

Challenges in diagnosing tuberculosis in children

INTRODUCTION

Clinical investigations of childhood tuberculosis (TB) are challenged by the paucibacillary nature of the disease and the difficulties in obtaining specimens. We investigated the challenges in diagnosing TB in children in a low-incidence country.

MATERIAL AND METHODS

The data were retrieved retrospectively from the paediatric departments at Danish university hospitals from April 2004 to March 2009 using the diagnosis code A15.0-A19.9 in children below the age of 15 years.

RESULTS

A total of 54 children were identified of whom 13 were native Danes. The remaining immigrants were from a range of countries, the majority from Somalia. In all, 44 children had pulmonary TB and the proportion of extrapulmonary TB was higher among immigrants than among Danes. The cardinal symptoms were fever, weight loss and cough. In 41 cases (76%), a combination of a positive tuberculin skin test, an abnormal chest X-ray and the clinical presentation led to initiation of treatment. TB diagnosis was confirmed later by culture in 29 cases. The median number of days from contact to the healthcare system to treatment initiation was two days for 23 children who were part of contact tracing and seven days for the remaining children. All children but one completed treatment, and three patients were retreated due to relapse. Side effects to treatment were observed in 20 cases. None of the patients died.

CONCLUSION

The majority of the children affected with TB were foreign-born with a higher proportion of extrapulmonary TB. The microbiological confirmation was low. A rapid onset of treatment was closely related to known, recent exposure.

BRCA1 testing should be offered to individuals with triple-negative breast cancer diagnosed below 50 years

BACKGROUND

Triple-negative (TN) tumours are the predominant breast cancer subtype in BRCA1 mutation carriers. Recently, it was proposed that all individuals below 50 years of age with TN breast cancer should be offered BRCA testing. We have evaluated the BRCA1 mutation frequency and the implications for clinical practice of undertaking genetic testing in women with TN breast cancer.

METHODS

We undertook BRCA1 mutation analysis in 308 individuals with TN breast cancer, 159 individuals from unselected series of breast cancer and 149 individuals from series ascertained on the basis of young age and/or family history.

RESULTS

BRCA1 mutations were present in 45 out of 308 individuals. Individuals with TN cancer <50 years had >10% likelihood of carrying a BRCA1 mutation in both the unselected (11 out of 58, 19%) and selected (26 out of 111, 23%) series. However, over a third would not have been offered testing using existing criteria. We estimate that testing all individuals with TN breast cancer <50 years would generate an extra 1200 tests annually in England.

CONCLUSION

Women with TN breast cancer diagnosed below 50 years have >10% likelihood of carrying a BRCA1 mutation and are therefore eligible for testing in most centres. However, implementation may place short-term logistical and financial burdens on genetic services.

Penile agenesis in adult

Penile agenesis (PA) is an extremely rare congenital anomaly with profound surgical and psychosocial consequences. Only seventy five cases have been reported in the literature, the highest age of presentation known seven years. We present a twenty six years old otherwise normal aphallic male with attraction to female sex and night emission through anus. The patient did not agree to the female gender assignment and functioning phallic reconstruction is practically unavailable. Early female gender assignment and feminizing perineal reconstruction (Vaginoplasty) in neonatal cases is the technically easier goal of treatment. Late presenting cases add difficulty to debated decision making of gender assignment.

Genome-wide association studies provide new insights into the genetic basis of testicular germ-cell tumour

Testicular germ-cell tumour (TGCT) is the most common cancer in young men, and genetic epidemiological studies suggest that the disease has a strong genetic basis. Until 2009, very little of this genetic component had been explained. Genome-wide association studies have since identified eight SNPs at six loci which together account for approximately 15% of the genetic risk of TGCT and offer novel biological insights into testicular germ-cell oncogenesis. In this review, we summarize the genetic epidemiology of TGCT, detail the contribution genome-wide association studies have made to our understanding of the genetic basis of TGCT and reflect on how future technological advances may assist in revealing the remaining genetic factors underlying TGCT susceptibility.

Application of Conductive Polymers in Bone Regeneration

The role of electromagnetism in the physiology of the human body and in the healing process is well accepted. Electroactive polymers, such as electrically conducting polymers, by virtue of their susceptibility to either electrical, mechanical, optical or thermal phenomena, could be utilized as an interface between the external world and the physiological environment1. In this study we have evaluated the utility of polypyrrole (PPy)-a conductive polymer, as an interactive substrate for inducing differentiation in bovine bone marrow stromal cells (BMSC). It was observed, the PPy is an excellent substrate for BMSC attachment, proliferation and differentiation. Furthermore, an application of an electrical stimulus (ES) to BMSC via PPy substrate was found to enhance the osteogenic commitment of these cells.

A novel HER2-positive breast cancer phenotype arising from germline TP53 mutations

INTRODUCTION

The Li-Fraumeni Syndrome is caused by a germline TP53 mutation and is associated with a high risk of breast cancer at young ages. Basal (triple negative) breast cancers are now well recognised to be a typical sub-type of breast cancer developing in a large proportion of BRCA1 gene carriers. We considered whether a similar narrow sub-type of breast cancer was found in TP53 gene mutation carriers.

OBJECTIVE

A hypothesis generating study to investigate whether there are specific breast tumour characteristics associated with germline TP53 mutations.

METHODS

Pathological characteristics in 12 breast cancers arising in nine patients carrying pathogenic TP53 mutations were compared to a reference panel of 231 young onset breast tumours included in the POSH study.

RESULTS

Patients carrying a TP53 mutation showed a significantly higher likelihood of developing a breast cancer with Human Epidermal growth factor Receptor (HER2) amplification (83%) when compared to the cohort of young onset breast cancer cases (16%); ER and PR status were equivalent between groups.

CONCLUSION

These findings suggest that breast cancer developing on a background of an inherited TP53 mutation is highly likely to present with amplification of HER2.

Case report of paediatric oxalate urolithiasis and a review of enteric hyperoxaluria

The formation of renal calculi secondary to enteric hyperoxaluria is rare in the paediatric population. We present the case of an 8-year-old boy who had short bowel syndrome resulting in enteric hyperoxaluria which led to the development of urolithiasis and bilateral ureteric strictures, both of which resolved with medical management. We also review the literature on enteric hyperoxaluria.

Rectal biopsy for Hirschsprung's disease--are we performing too many?

BACKGROUND

Rectal biopsy is considered the gold standard for the diagnosis of Hirschsprung's disease. The aim of this study was to evaluate the outcome of rectal biopsies performed in our institution, and to determine whether we are performing an adequate number of biopsies in patients presenting with features suggestive of this disease.

METHODS

A retrospective analysis was conducted of patients who underwent rectal biopsy to exclude Hirschsprung's disease over a seven year period between 2000 and 2006. The histological diagnosis of Hirschsprung's disease was made using haematoxylin and eosin as well as acetylcholinesterase on frozen section. Patients were grouped into three age categories: neonates (group A), infants (group B) and those over 1 year of age (group C). The results of the biopsies were compared between groups.

RESULTS

A total of 668 patients underwent rectal biopsy. 18 samples were insufficient. Based on the histological studies of 650 suitable samples, 73 (11%) were positive and 577 (89%) were negative for Hirschsprung's disease. Of the 73 positive biopsies, 34 (47%) were from group A, 20 (27%) from group B and 19 (26%) from group C. The percentage of positive biopsies was much higher in group A with 29% (34 out of 118) compared to group B with 15% (20 out of 135) and group C with 5% (19 out of 395). Three complications of minor rectal bleeding occurred.

CONCLUSIONS

With 3 complications and 18 insufficient samples out of 668, rectal biopsy is a safe procedure and remains the gold standard for the diagnosis of Hirschsprung's disease, despite the large number of negative biopsies. Contrary to some reports in the literature which question the need for rectal biopsy in those presenting after the neonatal period, 53% of our positive diagnoses were made in children presenting after this period, with 19 positive biopsies out of 395 (5%) performed in children above the age of 1 year.

Constitutional translocation breakpoint mapping by genome-wide paired-end sequencing identifies HACE1 as a putative Wilms tumour susceptibility gene

BACKGROUND

Localisation of the breakpoints of chromosomal translocations has aided the discovery of several disease genes but has traditionally required laborious investigation of chromosomes by fluorescent in situ hybridisation approaches. Here, a strategy that utilises genome-wide paired-end massively parallel DNA sequencing to rapidly map translocation breakpoints is reported. This method was used to fine map a de novo t(5;6)(q21;q21) translocation in a child with bilateral, young-onset Wilms tumour.

METHODS AND RESULTS

Genome-wide paired-end sequencing was performed for approximately 6 million randomly generated approximately 3 kb fragments from constitutional DNA containing the translocation, and six fragments in which one end mapped to chromosome 5 and the other to chromosome 6 were identified. This mapped the translocation breakpoints to within 1.7 kb. Then, PCR assays that amplified across the rearrangement junction were designed to characterise the breakpoints at sequence-level resolution. The 6q21 breakpoint transects and truncates HACE1, an E3 ubiquitin-protein ligase that has been implicated as a somatically inactivated target in Wilms tumourigenesis. To evaluate the contribution of HACE1 to Wilms tumour predisposition, the gene was mutationally screened in 450 individuals with Wilms tumour. One child with unilateral Wilms tumour and a truncating HACE1 mutation was identified.

CONCLUSIONS

These data indicate that constitutional disruption of HACE1 likely predisposes to Wilms tumour. However, HACE1 mutations are rare and therefore can only make a small contribution to Wilms tumour incidence. More broadly, this study demonstrates the utility of genome-wide paired-end sequencing in the delineation of apparently balanced chromosomal translocations, for which it is likely to become the method of choice.

Chain of evidence in sexual assault cases

Chain of evidence (COE) sampling is a legal concept demonstrating the journey of a sample from origin to court. Positive sexually transmitted infection (STI) results may have importance in criminal proceedings and require a demonstrated COE for them to be used as admissible evidence. A retrospective case-notes review of female sexual assault patients was carried out to review COE sampling in two clinics. Three hundred and eighteen patients underwent sexual health screening and COE sampling was indicated in 58 (18%). COE sampling was carried out in 44 (92%) of 48 indicated cases at the Haven (a dedicated sexual assault centre) and five (50%) of 10 at the Ambrose King Centre (a sexual health clinic). COE protocols should be in place in both sexual assault referral centres and sexual health clinics. In specialist clinics, with well-established guidelines and trained dedicated staff, COE sampling standards can be achieved.

Duodenal atresia: associated anomalies, prenatal diagnosis and outcome

BACKGROUND

The diagnosis of duodenal atresia is commonly made prenatally, either as an isolated lesion or due to its association with other chromosomal abnormalities (Robertson et al. in Semin Perinatol 18:182-195, 1994; Hemming and Rankin in J Prenat Diagn 27:1205-1211, 2007). The aim of this study was to describe the prevalence of associated anomalies, prenatal diagnostic accuracy and survival of cases of congenital duodenal atresia in our institution.

METHODS

All cases of duodenal atresia registered with our local congenital anomaly register over a 10-year period, 1995-2004 inclusive, were studied, including those resulting in termination of pregnancies, stillbirths, intrauterine deaths and neonatal deaths. To ensure high-case ascertainment, data were cross checked with prenatal ultrasound, cytogenetic laboratory, pathology department and neonatal surgical data base. Data were analysed for associated anomalies, accuracy of prenatal diagnosis and neonatal outcomes.

RESULTS

A total of 65 patients were initially diagnosed as having duodenal atresia, of these 4 were subsequently excluded (1 postnatal normal bowel and 3 high jejunal atresias). In the remaining 61 cases, 35 (57%) had an association with other congenital abnormalities and 26 (43%) were isolated anomalies. Thirty-five were male and 26 female (M:F = 1.4:1). Twenty-one out of 29 (72%) patients prenatally diagnosed, compared with 14 out of 32 (44%) patients diagnosed postnatally had associated anomalies. Duodenal atresia was suspected on routine prenatal ultrasonography at 20-week gestation in 33 cases and confirmed in 29 (48%) cases with 4 false-positive diagnoses (1 normal bowel and 3 high jejunal atresias). No prenatal diagnosis was made in 32 (52%) babies. Of the 61 cases, 53 were live births with 2 early neonatal deaths (1 cardiac and 1 VACTERL), 5 terminations, 2 intrauterine deaths and 1 stillbirth (Fig. 3). Overall neonatal survival was 96% (51 cases). Mortality in the group diagnosed prenatally was 34 % (10 cases).

CONCLUSION

This study shows an overall increased association of duodenal atresia with Down's syndrome. In the group diagnosed prenatally, mortality as well as the association with other congenital anomalies was found to be higher. We have demonstrated a greater prenatal diagnostic accuracy, but confirm postnatal outcomes similar to previous studies.

Patent processus vaginalis: a window to the abdomen

A patent processus vaginalis (PPV) allows a communication between the peritoneum and scrotum. Hydrocoele is the usual presentation of a PPV in children. However, with intraabdominal pathology the patent PPV may provide the first clue to the mischief within the abdomen. We present here two unusual cases associated with a PPV and migration of intraabdominal contents from the abdomen to the scrotum.

Comparison between open and thoracoscopic resection of congenital lung lesions

PURPOSE

This study compares the outcome between thoracoscopic and thoracotomy resection of congenital lung lesions.

METHODS

From November 2005 to August 2007, 14 consecutive cases of video-assisted thoracoscopic (VATS) lung resections have been performed in our institution. A retrospective review comparing these cases to the previous open thoracotomies for lung resection was performed. Intraoperative and early postoperative results were compared.

RESULTS

The mean age for VATS resection was 10 months compared with 7 months for thoracotomy. There were no major intraoperative complications. One case was converted from thoracoscopy to thoracotomy, and there was one anesthetic failed attempt of VATS resection, which was then performed open. Seven VATS resections and 6 thoracotomies were for congenital cystic adenomatous malformations. Intraoperative chest drains were used for all VATS resections but only 10 of the 14 thoracotomies, one of which developed a tension pneumothorax within hours of discharge. Perioperative outcomes including time to removal of chest drain, length of postoperative intravenous opioid requirement, and hospital stay were similar for both groups. Three had postoperative complications. Operative time was significantly lower in the thoracotomy group (124 minutes compared with 170 minutes, P < .05). The subgroup of congenital lobar emphysema had a particularly prolonged VATS resection time of 220 vs 155 minutes (P < .05). The thoracotomy group was more likely to receive adjuvant regional anesthesia (12 of 14 compared with 5 of 14).

CONCLUSIONS

Thoracoscopic resection of lung lesions results in longer operative time but is a safe and feasible alternative to open thoracotomy. Congenital lobar emphysema is a subgroup more challenging thoracoscopically, and it is recommended that these should be preselected for open surgery.

Integrated community-based sexual health services for young people in urban areas: are we meeting the needs of the local community?

Community-based sexual health services (SHS) are intended to improve access for people who may have difficulty attending traditional genitourinary medicine clinics. The objective of this study was to review uptake of sexually transmitted infection (STI) testing in an outreach clinic for those under 25 in an area where Black and minority ethnic groups comprise the majority of the local population. A retrospective case-notes review was undertaken of those attending. Standards were that Fraser guidelines should be completed in all under 16-year-old and all clients should be offered STI testing, HIV testing and contraception (if applicable) in accordance with local standards. One hundred and seventeen clients attended. Ten percent self-reported ethnicity was Asian. Thirty-six (31%) clients tested for chlamydia. Thirty (26%) had an HIV test. Five (14% of those tested) had a positive nucleic acid amplification test for chlamydia. Five (13%) of those requesting long term contraception had STI testing. This service has successfully improved access to STI screening. However, there may have been missed opportunities to offer tests in those requesting contraception. Under-representation of those of non-white ethnicity suggests access to SHS may be a particular problem and further work is required to improve the sexual health of the local community.

Partial pressure of oxygen in arterial blood in normal pregnant women in Dhaka city

In the present study the partial pressure of oxygen in arterial blood (PaO2) was estimated in 32 women in Dhaka city. For this purpose a total 32 women subjects with age ranged from 25 years to 35 years without any recent history of respiratory diseases were selected and divided into 8 healthy non-pregnant women as control and 24 normal pregnant women as experimental group. Experimental group was further divided into 8 first trimester, 8 second trimester & 8 third trimester of pregnant women. The PaO2 was estimated by using "Easy Blood Gas Auto Analyzer". The PaO2 was estimated during the 1st, 2nd, 3rd trimesters of pregnant women and non-pregnant women. The mean of measured values of PaO2 were analyzed statistically in relation to 1st, 2nd, 3rd trimesters of pregnant women & non-pregnant women. The PaO2 was significantly higher in 1st trimester, 2nd trimester & 3rd trimester of pregnant women than that of non-pregnant women. There were no statistically significant difference of PaO2 between the 1st trimester and 2nd trimester; between the 1st trimester and 3rd trimester; and between the 2nd trimester and 3rd trimester of pregnant women. It may be concluded that the causes of progressively increased PaO2 throughout the pregnancy were most likely to be due to effect of progesterone causing hyperventilation.

Evaluation of objective structured practical examination and traditional practical examination

To evaluate the competency of Objective Structured Practical Examination (OSPE) as an assessment technique compared to Traditional Practical Examination (TDPE) in assessment of laboratory component of physiology, the results of Physiology practical examination of 400 students from 4 Medical Colleges, two Government and two non Government (Dhaka Medical College, Mymensingh Medical College, Bangladesh Medical College, Uttara Women's Medical College) under Dhaka University were studied. Students' performance in OSPE and TDPE was compared. Mean score obtained in OSPE was 77.72+/-0.66 and found significantly higher than that for TDPE (64.44+/-0.61). Again mean scores achieved in OSPE were compared among different Medical Colleges and significant difference was noted. In OSPE, male students achieved significantly higher score than that of female students, especially in responding question station. The outcome of the present study thus indicates that OSPE is a better choice as an assessment technique over the Traditional method measuring wide range of practical skill. It may be concluded that it is important for competency based performance discrimination and it also helps improving students performance quality in laboratory exercise.

Performance of laser bonded glass/polyimide microjoints in cerebrospinal fluid

In this paper, laser bonded microjoints between glass and polyimide is considered to examine their potential applicability in encapsulating neural implants. To facilitate bonding between polyimide and glass, a thin titanium film with a thickness of 2 microm was deposited on borosilicate glass plates by a physical vapor deposition (PVD) process. Titanium coated glass was then joined with polyimide by using a cw fiber laser emitting at a wavelength of 1.1 microm (1.0 W) to prepare several tensile samples. Some of the samples were exposed to artificial cerebrospinal fluid (aCSF) at 37 degrees C for two weeks to assess long-term integrity of the joints. Both the as-received and aCSF soaked samples were subjected to uniaxial tensile loads for bond strengths measurements. The bond strengths for the as-received and aCSF soaked samples were measured to be 7.31 and 5.33 N/mm, respectively. Although the long-term exposure of the microjoints to aCSF has resulted in 26% reduction of bond strength, the samples still retain considerably high strength as compared with the titanium-polyimide samples. The failed glass/polyimide samples were also analyzed using optical microscopy, and failure mechanisms are discussed. In addition, a two dimensional finite element analysis (FEA) was conducted to understand the stress distribution within the substrate materials while the samples are in tension. The FEA results match reasonably well with the experimental load-displacement curves for as-received samples. Detailed discussion on various stress contours is presented in the paper, and the failure mechanisms observed from the experiment are shown in good agreement with the FEA predicted ones.

Surveillance for Wilms tumour in at-risk children: pragmatic recommendations for best practice

BACKGROUND

Most Wilms tumours occur in otherwise healthy children, but a small proportion occur in children with genetic syndromes associated with increased risks of Wilms tumour. Surveillance for Wilms tumour has become widespread, despite a lack of clarity about which children are at increased risk of these tumours and limited evidence of the efficacy of screening or guidance as to how screening should be implemented.

METHODS

The available literature was reviewed.

RESULTS

The potential risks and benefits of Wilms tumour surveillance are finely balanced and there is no clear evidence that screening reduces mortality or morbidity. Prospective evidence-based data on the efficacy of Wilms tumour screening would be difficult and costly to generate and are unlikely to become available in the foreseeable future.

CONCLUSIONS

The following pragmatic recommendations have been formulated for Wilms tumour surveillance in children at risk, based on our review: (1) Surveillance should be offered to children at >5% risk of Wilms tumour. (2) Surveillance should only be offered after review by a clinical geneticist. (3) Surveillance should be carried out by renal ultrasonography every 3-4 months. (4) Surveillance should continue until 5 years of age in all conditions except Beckwith-Wiedemann syndrome, Simpson-Golabi-Behmel syndrome and some familial Wilms tumour pedigrees where it should continue until 7 years. (5) Surveillance can be undertaken at a local centre, but should be carried out by someone with experience in paediatric ultrasonography. (6) Screen-detected lesions should be managed at a specialist centre.