Association between Parvovirus B19 and thyroid/celiac autoantibodies among T1DM pediatric patients

OBJECTIVE

In recent years, an overwhelming association between Pediatric Type 1 Diabetes Mellitus (T1DM) and autoimmune diseases has been largely reported. The current study was designed to determine a possible association between autoimmune thyroiditis (AIT), celiac disease (CD) - associated autoantibodies, and Parvovirus B19 infection among pediatric T1DM cases in the southwestern region of Saudi Arabia.

PATIENTS AND METHODS

Blood samples from age groups 1-18 years attending the Diabetic Clinic were collected over a period of 12 months. Serum anti-thyroid peroxidase (TPO), anti-thyroglobulin (TG), anti-tissue transglutaminase immunoglobulin A (TG-IgA), endomysial IgA (EMA-IgA), Parvovirus B19-IgG and IgM antibodies were detected by standard methods.

RESULTS

The results showed the prevalence of autoantibodies against thyroid and CD among pediatric T1DM patients to be 44 (25%) and 25 (14.4%), respectively. The prevalence of antibodies against B19 was 70 (40%). Further determination of the prevalence of Parvovirus B19-IgG antibodies and thyroid antibodies among T1DM pediatric patients revealed that there was a significant association between them with a p<0.0491.

CONCLUSIONS

The prevalence of autoantibodies against the thyroid was higher among the seropositive Parvovirus B19 children with T1DM. A positive association between the prevalence of autoantibodies against thyroid disease and the increase in the duration of diabetes was also noted. Hence, periodic screening of T1DM patients for B19 antibodies and autoantibodies for thyroid is crucial.

Shrimp classification for white spot syndrome detection through enhanced gated recurrent unit-based wild geese migration optimization algorithm

The major dangerous viral infection for cultivated shrimps is WSSV. The virus is extremely dangerous, spreads swiftly, and may result in up to 100% mortality in 3-10 days. The vast wrapped double stranded DNA virus known as WSSV describes a member of the Nimaviridae viral family's species Whispovirus. It impacts a variety of crustacean hosts but predominantly marine shrimp species that are raised for commercial purposes. The entire age groups are affected by the virus, which leads to widespread mortality. Mesodermal and ectodermal tissues, like the lymph nodes, gills, and cuticular epithelium, represents the centres of infection. Complete genome sequencing related to the WSSV strains from Thailand, China, and Taiwan has identified minute genetic variations amongst them. There exist conflicting findings on the causes of WSSV pathogenicity, which involve variations in the size associated with the genome, the count of tandem repeats, and the availability or lack of certain proteins. Hence, this paper plans to perform the shrimp classification for the WSSV on the basis of novel deep learning methodology. Initially, the data is gathered from the farms as well as internet sources. Next, the pre-processing of the gathered shrimp images is accomplished using the LBP technique. These pre-processed images undergo the segmentation process utilizing the TGVFCMS approach. The extraction of the features from these segmented images is performed by the PLDA technique. In the final step, the classification of the shrimp into healthy shrimp and WSSV affected shrimp is done by the EGRU, in which the parameter tuning is accomplished by the wild GMO algorithm with the consideration of accuracy maximization as the major objective function. Performance indicators for accuracy have been compared with those of various conventional methods, and the results show that the methodology is capable of accurately identifying the shrimp WSSV illness.

Energetic Electron Precipitation Driven by Electromagnetic Ion Cyclotron Waves from ELFIN's Low Altitude Perspective

We review comprehensive observations of electromagnetic ion cyclotron (EMIC) wave-driven energetic electron precipitation using data collected by the energetic electron detector on the Electron Losses and Fields InvestigatioN (ELFIN) mission, two polar-orbiting low-altitude spinning CubeSats, measuring 50-5000 keV electrons with good pitch-angle and energy resolution. EMIC wave-driven precipitation exhibits a distinct signature in energy-spectrograms of the precipitating-to-trapped flux ratio: peaks at >0.5 MeV which are abrupt (bursty) (lasting ∼17 s, or Δ L ∼ 0.56 ) with significant substructure (occasionally down to sub-second timescale). We attribute the bursty nature of the precipitation to the spatial extent and structuredness of the wave field at the equator. Multiple ELFIN passes over the same MLT sector allow us to study the spatial and temporal evolution of the EMIC wave - electron interaction region. Case studies employing conjugate ground-based or equatorial observations of the EMIC waves reveal that the energy of moderate and strong precipitation at ELFIN approximately agrees with theoretical expectations for cyclotron resonant interactions in a cold plasma. Using multiple years of ELFIN data uniformly distributed in local time, we assemble a statistical database of ∼50 events of strong EMIC wave-driven precipitation. Most reside at L ∼ 5 - 7 at dusk, while a smaller subset exists at L ∼ 8 - 12 at post-midnight. The energies of the peak-precipitation ratio and of the half-peak precipitation ratio (our proxy for the minimum resonance energy) exhibit an L -shell dependence in good agreement with theoretical estimates based on prior statistical observations of EMIC wave power spectra. The precipitation ratio's spectral shape for the most intense events has an exponential falloff away from the peak (i.e., on either side of ∼ 1.45 MeV). It too agrees well with quasi-linear diffusion theory based on prior statistics of wave spectra. It should be noted though that this diffusive treatment likely includes effects from nonlinear resonant interactions (especially at high energies) and nonresonant effects from sharp wave packet edges (at low energies). Sub-MeV electron precipitation observed concurrently with strong EMIC wave-driven >1 MeV precipitation has a spectral shape that is consistent with efficient pitch-angle scattering down to ∼ 200-300 keV by much less intense higher frequency EMIC waves at dusk (where such waves are most frequent). At ∼100 keV, whistler-mode chorus may be implicated in concurrent precipitation. These results confirm the critical role of EMIC waves in driving relativistic electron losses. Nonlinear effects may abound and require further investigation.

CD38: an ecto-enzyme with functional diversity in T cells

CD38, a nicotinamide adenine dinucleotide (NAD)+ glycohydrolase, is considered an activation marker of T lymphocytes in humans that is highly expressed during certain chronic viral infections. T cells constitute a heterogeneous population; however, the expression and function of CD38 has been poorly defined in distinct T cell compartments. We investigated the expression and function of CD38 in naïve and effector T cell subsets in the peripheral blood mononuclear cells (PBMCs) from healthy donors and people with HIV (PWH) using flow cytometry. Further, we examined the impact of CD38 expression on intracellular NAD+ levels, mitochondrial function, and intracellular cytokine production in response to virus-specific peptide stimulation (HIV Group specific antigen; Gag). Naïve T cells from healthy donors showed remarkably higher levels of CD38 expression than those of effector cells with concomitant reduced intracellular NAD+ levels, decreased mitochondrial membrane potential and lower metabolic activity. Blockade of CD38 by a small molecule inhibitor, 78c, increased metabolic function, mitochondrial mass and mitochondrial membrane potential in the naïve T lymphocytes. PWH exhibited similar frequencies of CD38+ cells in the T cell subsets. However, CD38 expression increased on Gag-specific IFN-γ and TNF-α producing cell compartments among effector T cells. 78c treatment resulted in reduced cytokine production, indicating its distinct expression and functional profile in different T cell subsets. In summary, in naïve cells high CD38 expression reflects lower metabolic activity, while in effector cells it preferentially contributes to immunopathogenesis by increasing inflammatory cytokine production. Thus, CD38 may be considered as a therapeutic target in chronic viral infections to reduce ongoing immune activation.

Preconception vitamin D and miscarriage in a prospective cohort study

STUDY QUESTION

Is preconception vitamin D level associated with the risk of miscarriage?

SUMMARY ANSWER

Preconception vitamin D levels are not associated with the risk of miscarriage in a population of women conceiving naturally.

WHAT IS KNOWN ALREADY

In humans, low vitamin D has been associated with prolonged menstrual cycles, delayed ovulation and a lower probability of conception. Animal and in vitro data indicate that vitamin D may affect implantation.

STUDY DESIGN, SIZE, DURATION

This prospective time-to-pregnancy study included 362 women who were trying to conceive naturally between 2008 and 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study included participants who had been trying to conceive naturally for 3 months or less at enrollment and aged 30-44 years. A preconception blood sample was collected and 25-hydroxyvitamin D [25(OH)D] was measured. Women who conceived (N = 362) were at risk of a miscarriage from the day of a reported positive pregnancy test until either a participant-reported pregnancy loss or 20 weeks post day of last menstrual period, whichever came first. Gestational age was defined by ovulation. Time to miscarriage (days) or censoring was modeled using a multivariate Cox proportional hazards model. Multiple imputation was performed for missing covariates and missing day of ovulation.

MAIN RESULTS AND THE ROLE OF CHANCE

The mean age was 33 years (SD: 3.0 years). Mean 25(OH)D was lower among those who reported their race as African-American and those with a higher BMI. After adjustment for age, race, BMI, education, exercise, alcohol and caffeine intake, compared to the referent group (30-<40 ng/ml), the hazard ratio (HR) and 95% CI for those with a low 25(OH)D level (<30 ng/ml) was 1.10 (CI: 0.62, 1.91). Among participants with a higher 25(OH)D level (≥40 ng/ml), the HR was 1.07 (CI: 0.62, 1.84).

LIMITATIONS, REASONS FOR CAUTION

This study was limited by a 25(OH)D measurement at only a single time point. A large percentage of women in this study had sufficient vitamin D levels, which may have limited our power to detect an effect of deficiency. Women in this study were older (30-44 years), and predominantly reported their race as White which may limit generalizability.

WIDER IMPLICATIONS OF THE FINDINGS

The findings of this study do not suggest an association between preconception vitamin D and miscarriage. Future research should focus on women at greater risk for miscarriage or in populations at risk for vitamin D deficiency or on supplementation.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported in part by the Intramural Research Program of the NIH, National Institute of Environmental Health Sciences (Z01ES103333). This research was also supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health (NIH) under award numbers R00HD079659 and R01HD067683. The authors have no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

703 Is the Grass Always Greener on the Other Side? – How Do Breast Cancer Patients Feel About Moving to a ‘Green Hub’?

Aim

Between January and September 2020 our base hospital recorded zero COVID-19 incidence in breast surgery patients, in 30 days post-op, with stringent admission protocols including 14 days self-isolation, PCR testing, ‘green’ wards and designated ‘green’ theatres. However, as the UK entered its third lockdown in January 6th2021 the decision was made to move breast cancer surgery off-site to a ‘green hub’ 43 miles away. The aim of this study was to assess the impact this had on patients.

Method

Patients who had surgery moved off-site were requested to anonymously complete a questionnaire which was either posted or handed to them at follow-up. The questionnaire contained 11 Multiple Choice questions and a comments section.

Results

16 of 19 patients (84.21%) responded to the questionnaire. 16 of 16 (100%) understood the reason for the move. 2 (12.5%) stated that it increased anxiety/stress levels while 3 (18.75%) reported the opposite, and the remainder were neutral. 14 (87.5%) said the move made them feel safer, 1 (6.25%) did not feel safer, with the remaining 1 (6.25%) unsure. 15 (93.75%) felt they received enough information at base and 16 (100%) received sufficient discharge information at the ‘green hub’. All 16 (100%) were satisfied with the move off-site but only 15 (93.75%) supported the decision.

Conclusions

The responses indicate that the decision to move breast surgery off-site was supported and well understood. And while for a minority of patients this increased pre-operative anxiety/stress levels, it did make the majority feel safer.

P-186 ART outcomes in ICSI cycles with normal and morphologically variant (MV) oocytes in the same cohort

Study question

To evaluate ART outcomes of ICSI cycles from normal oocytes (A) Vs normal and MV oocytes (B) and all MV oocytes in the cohort (C).

Summary answer

Clinical pregnancy rate (CPR), Implantation rate (IR) and live birth rates (LBR) were clinically satisfactory even in group C

What is known already

In routine IVF laboratories, oocytes are subjected to a rapid evaluation using an inverted microscope to evaluate morphological variants in the cytoplasm, peri-vitelline space and zona pellucida, which is very superficial and subjective. Post ICSI, focus entirely shifts to embryo morphology studies and outcome of such morphologically variant oocytes are less explored. Transferring embryos selected by morphological assessment alone and by neglecting oocyte quality may result in compromised in vitro development, low pregnancy rates, miscarriage rates and further negative consequences

Study design, size, duration

A prospective observational study of 212 women who underwent ICSI cycles from September 2020 to December 2021 were taken up for the study of which, 106 subjects had all normal oocytes in the cohort (A), 67 subjects had both normal and abnormal oocytes (B) and 28 subjects had all morphologically variant oocytes (C)

Participants/materials, setting, methods

212 consecutive women aged 24-38 undergoing ICSI cycles in a private fertility hospital were included. ICSI was performed for all oocytes, embryos cultured until Day 5. Primary outcome measure was to compare ART outcomes between three groups. Secondary outcome measure was to determine minimum threshold of normal oocytes required for higher live birth rate by comparing ART outcomes of patients with at least 7 normal oocytes (n = 51) Vs those with &lt;7 normal oocytes (n = 55).

Main results and the role of chance

The study showed a highly significant difference in CPR (P &lt; 0.0001), IR (P = 0.0001) and LBR (P = 0.01) when embryos with all morphologically normal oocytes were transferred compared to embryos with morphologically variant oocytes were transferred. There was no difference in ICSI outcomes including fertilization rate, ICSI degeneration rate, early embryo development rate and blastulation rate between the three groups.

The study also revealed that a minimum of 7 normal oocytes in the cohort gave significant difference in CPR (P = 0.01), IR (P = 0.02) and LBR (P = 0.0005) when compared to the women who had less than 7 normal oocytes in the same cohort.

The outcome of each of the normal and MV oocytes were evaluated by culturing the MV oocytes separately in culture until Day 5. The embryos formed from MV oocytes were vitrified separately and was transferred only when there were no embryos were available for transfer from the normal oocytes obtained from the same cohort.

Limitations, reasons for caution

The study is to be continued further, until &gt;1000 oocytes are evaluated to confirm if more robust results are obtained, so that sample size in all the three groups are also higher.

Wider implications of the findings

This study implies that instead of discarding or not injecting oocytes with morphological variants, transferring those embryos with some morphologically variant oocytes also results in a clinically satisfactory outcome and live birth rates.

Trial registration number

Not applicable

Innovations for the future of breast surgery

BACKGROUND

Future innovations in science and technology with an impact on multimodal breast cancer management from a surgical perspective are discussed in this narrative review. The work was undertaken in response to the Commission on the Future of Surgery project initiated by the Royal College of Surgeons of England.

METHODS

Expert opinion was sought around themes of surgical de-escalation, reduction in treatment morbidities, and improving the accuracy of breast-conserving surgery in terms of margin status. There was emphasis on how the primacy of surgical excision in an era of oncoplastic and reconstructive surgery is increasingly being challenged, with more effective systemic therapies that target residual disease burden, and permit response-adapted approaches to both breast and axillary surgery.

RESULTS

Technologies for intraoperative margin assessment can potentially half re-excision rates after breast-conserving surgery, and sentinel lymph node biopsy will become a therapeutic procedure for many patients with node-positive disease treated either with surgery or chemotherapy as the primary modality. Genomic profiling of tumours can aid in the selection of patients for neoadjuvant and adjuvant therapies as well as prevention strategies. Molecular subtypes are predictive of response to induction therapies and reductive approaches to surgery in the breast or axilla.

CONCLUSION

Treatments are increasingly being tailored and based on improved understanding of tumour biology and relevant biomarkers to determine absolute benefit and permit delivery of cost-effective healthcare. Patient involvement is crucial for breast cancer studies to ensure relevance and outcome measures that are objective, meaningful, and patient-centred.

Iliotibial band enthesopathy: an unusual cause of lateral knee pain post total knee replacement

Iliotibial band (ITB) pathology is one of the main causes of lateral knee pain. The enthesopathy of the ITB at its insertion post total knee replacement (TKR) is a rare cause of lateral knee pain. We describe a series of cases of ITB enthesopathy with sonographic findings and management.

The ELFIN Mission

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93^∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (T_orbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (T_spin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

Impact of bariatric surgery on cardiovascular outcomes and mortality: a population-based cohort study

Background

Cohort studies have shown that bariatric surgery may reduce the incidence of and mortality from cardiovascular disease (CVD), but studies using real-world data are limited. This study examined the impact of bariatric surgery on incident CVD, hypertension and atrial fibrillation, and all-cause mortality.

Methods

A retrospective, matched, controlled cohort study of The Health Improvement Network primary care database (from 1 January 1990 to 31 January 2018) was performed (approximately 6 per cent of the UK population). Adults with a BMI of 30 kg/m2 or above who did not have gastric cancer were included as the exposed group. Each exposed patient, who had undergone bariatric surgery, was matched for age, sex, BMI and presence of type 2 diabetes mellitus (T2DM) with two controls who had not had bariatric surgery.

Results

A total of 5170 exposed and 9995 control participants were included; their mean(s.d.) age was 45·3(10·5) years and 21·5 per cent (3265 of 15 165 participants) had T2DM. Median follow-up was 3·9 (i.q.r. 1·8– 6·4) years. Mean(s.d.) percentage weight loss was 20·0(13·2) and 0·8(9·5) per cent in exposed and control groups respectively. Overall, bariatric surgery was not associated with a significantly lower CVD risk (adjusted hazard ratio (HR) 0·80; 95 per cent c.i. 0·62 to 1·02; P = 0·074). Only in the gastric bypass group was a significant impact on CVD observed (HR 0·53, 0·34 to 0·81; P = 0·003). Bariatric surgery was associated with significant reduction in all-cause mortality (adjusted HR 0·70, 0·55 to 0·89; P = 0·004), hypertension (adjusted HR 0·41, 0·34 to 0·50; P &lt; 0·001) and heart failure (adjusted HR 0·57, 0·34 to 0·96; P = 0·033). Outcomes were similar in patients with and those without T2DM (exposed versus controls), except for incident atrial fibrillation, which was reduced in the T2DM group.

Conclusion

Bariatric surgery is associated with a reduced risk of hypertension, heart failure and mortality, compared with routine care. Gastric bypass was associated with reduced risk of CVD compared to routine care.

Gestational dyslipidaemia and adverse birthweight outcomes: a systematic review and meta-analysis

BACKGROUND

Low and high birthweight is known to increase the risk of acute and longer-term adverse outcomes, such as stillbirth, infant mortality, obesity, type 2 diabetes and cardiovascular diseases. Gestational dyslipidaemia is associated with a numbers of adverse birth outcomes, but evidence regarding birthweight is still inconsistent to reliably inform clinical practice and treatment recommendations.

OBJECTIVE

The aim of this study was to explore the relationship between maternal gestational dyslipidaemia and neonatal health outcomes, namely, birthweight, metabolic factors and inflammatory parameters.

METHODS

We searched systematically Embase, MEDLINE, PubMed, CINAHL Plus and Cochrane Library up to 1 August 2016 (with an updated search in MEDLINE at the end of July 2017) for longitudinal studies that assessed the association of maternal lipid levels during pregnancy with neonatal birthweight, or metabolic and inflammatory parameters up to 3 years old.

RESULTS

Data from 46 publications including 31,402 pregnancies suggest that maternal high triglycerides and low high-density-lipoprotein cholesterol levels throughout pregnancy are associated with increased birthweight, higher risk of large for gestational age and macrosomia and lower risk of small-for-gestational age. The findings were consistent across the studied populations, but stronger associations were observed in women who were overweight or obese prior to pregnancy.

CONCLUSIONS

This meta-analysis suggested that the potential under-recognized adverse effects of intrauterine exposure to maternal dyslipidaemia may warrant further investigation into the relationship between maternal dyslipidaemia and birthweight in large prospective cohorts or in randomized trials.

A nonlinear model of cell interaction with an acoustic field

A theoretical and experimental nonlinear analysis of cellular response/displacement to ultrasound excitations is presented. Linear cell models can predict the resonant frequency (f_R∼5MHz), but only a nonlinear analysis can reveal the amount of mechanical energy that couples into the cell and the bifurcation behavior of the cell when it is excited near resonance. The cell dynamics is described by the nonlinear viscoelastic constitutive behavior of the cytoplasm, nucleus and their respective membranes, in the presence of a fluid with an oscillating pressure field. The method of multiple scales is used to derive the amplitude of oscillation of the cytoplasm and nucleus as a function of frequency. A major finding is the existence of multiple solutions for a range of sub-resonant frequencies. At positive detuning (f>f_R), the mechanical energy that couples into the cell is small, it is higher at resonance but significantly higher at sub-resonant frequencies in the multiplicity range. Experimentally it was shown when 3.5MHz is approached sub- and supra-resonance and 6.5MHz is approached sub-resonance, gene expression was statistically higher than that when stimulated directly. Thus, there exists an optimal range of frequencies for ultrasound treatment - in the region of multiplicity where deformation and thus mechanical energy coupling is maximized. The ultrasound protocol must be designed to operate at the solution associated with the higher mechanical energy - thus the start-up conditions should be in the domain of attraction of the high energy solution.

Abstract P3-11-01: Prophylactic contralateral mastectomy - A valid choice?

This abstract was withdrawn by the authors.

Super-giant magnetoresistance at room-temperature in copper nanowires due to magnetic field modulation of potential barrier heights at nanowire-contact interfaces

We have observed a super-giant (∼10 000 000%) negative magnetoresistance at 39 mT field in Cu nanowires contacted with Au contact pads. In these nanowires, potential barriers form at the two Cu/Au interfaces because of Cu oxidation that results in an ultrathin copper oxide layer forming between Cu and Au. Current flows when electrons tunnel through, and/or thermionically emit over, these barriers. A magnetic field applied transverse to the direction of current flow along the wire deflects electrons toward one edge of the wire because of the Lorentz force, causing electron accumulation at that edge and depletion at the other. This lowers the potential barrier at the accumulated edge and raises it at the depleted edge, causing a super-giant magnetoresistance at room temperature.

Desensitization to Mycofenolate Mofetil: a novel 12 step protocol

The use of MMF has become standard practice in many solid organ transplant recipients due its efficacy and favorable risk profile compared to other immunosuppressants. There has been a single case report of successful MMF desensitization. However, this protocol did not follow current Drug practice parameters. We report a successful desensitization to MMF in a double heart-kidney transplant recipient.

DRD4 and DAT1 VNTR Genotyping in Children with Attention Deficit Hyperactivity Disorder

The dopamine receptor-D4 and the dopamine transporter have been investigated for their role in attention deficit hyperactivity disorder (ADHD) in children. Reports of their genetic association with ADHD have shown mixed results. The aim of the study was to evaluate the association of variable number tandem repeats (VNTRs) of the DRD4 and DAT1 genes with ADHD in children. A pilot 1:1 case control study, with 44 clinically confirmed ADHD cases and 44 age/gender matched healthy controls, was conducted at a tertiary care centre in Mumbai. Variable number tandem repeats of DRD4 exon 3, DAT1 intron 8 and 3'UTR were genotyped by PCR-AGE. Several allele repeats of the genes were observed in the screened subjects. Statistical significance was observed for the 10R/10R genotype of the DAT1 3'UTR VNTR between cases and controls.

Prevalence and management of ovarian venous insufficiency in the presence of leg venous insufficiency

Objective: The correlation between ovarian venous insufficiency and lower limb venous insufficiency remains poorly understood. Clinically, incompetent ovarian veins in association with lower extremity varicose veins are suspected when leg varicose veins are found in atypical distributions. Such distributions include upper lateral or posterior thigh, on the buttocks, crossing the inguinal ligament, and also in the vulval or perineal regions. The aim of this study was to determine the prevalence of ovarian venous insufficiency in those with clinically suspicious varicose veins, and to assess the effectiveness of ovarian venous embolization/ligation in treating this condition.

Methods: Between June 2001 and December 2004, 424 female patients with lower limb superficial venous insufficiency were seen by a single vascular surgeon. These patients were clinically assessed, and those with atypical varicose veins were investigated with venous duplex examination and magnetic resonance imaging (MRI) venography. Patients with proven ovarian venous insufficiency were offered venography with a view to embolization or laparoscopic ligation.

Results: A total of seven patients were clinically suspected of having ovarian venous insufficiency, of which three had recurrent varicose veins (42.9%). Of these, six were confirmed on MRI venography with the left side being more affected than the right; one of them had an occluded vena cava, three were treated by embolization, and two had laparoscopic ligation.

Discussion: The prevalence of clinically detectable ovarian venous insufficiency in association with lower extremity varicose veins is in the region of 1.65%. Compared with the estimated prevalence of incidental ovarian venous insufficiency of 10–47%, this suggests that only a minority of incompetent ovarian veins will present with clinically detectable lower limb venous insufficiency. In our opinion, patients with signs suggestive of ovarian venous insufficiency in association with lower limb venous insufficiency should have their ovarian insufficiency controlled prior to embarking on limb venous surgery.

Breast reconstruction in older patients: A literature review of the decision-making process

AIM

Women not undergoing breast reconstruction after mastectomy tend to be older. This review aims to aid in effective, evidence-based choices regarding breast reconstruction in an older population, appraising the influencing patient factors described in the literature and those directing the reconstructive surgeon. This may refute current misconceptions and ensure surgical decisions are made based on evidence without ageist assumptions. The review forms the basis of an evidence-based algorithm addressing each step of the decision-making process.

METHOD

A literature search was conducted using PubMed, Medline, Evidence.nhs.uk and the Cochrane database. Search terms initially were breast reconstruction, mastectomy, elderly, older, decision, reasons and rationale. A separate literature search was performed for each of the individual 'steps' in the decision-making process.

RESULTS

Overall, 44 papers were obtained. For each section of the decision-making process, titles and abstracts were screened for relevance. Only English language papers were included.

CONCLUSION

If reconstruction is oncologically plausible and co-morbidities and frailty formally assessed, older women should be actively informed about breast reconstruction, receive support and engage in 'shared decision-making'. The older patient is less likely to do research independently. Amongst other factors, body image, cancer fears, employment and carer responsibilities play a part in the decision. With adequate preoperative and frailty assessment and early involvement of the geriatrician and anaesthetist, microsurgical reconstruction is safe. Autologous reconstruction has better long-term outcomes than implant-based reconstructions in this age group, correlating with improved survival and longevity of reconstruction. Age alone should not be considered a contraindication to breast reconstruction.

P21-activated kinase 1 (Pak1) signaling influences therapeutic outcome in pancreatic cancer

BACKGROUND

Therapeutic resistance to gemcitabine in pancreatic ductal adenocarcinoma (PDAC) is attributed to various cellular mechanisms and signaling molecules that influence as a single factor or in combination.

DESIGN

In this study, utilizing in vitro p21-activated kinase 1 (Pak1) overexpression and knockdown cell line models along with in vivo athymic mouse tumor xenograft models and clinical samples, we demonstrate that Pak1 is a crucial signaling kinase in gemcitabine resistance.

RESULTS

Pak1 kindles resistance via modulation of epithelial-mesenchymal transition and activation of pancreatic stellate cells. Our results from gemcitabine-resistant and -sensitive cell line models showed that elevated Pak1 kinase activity is required to confer gemcitabine resistance. This was substantiated by elevated levels of phosphorylated Pak1 and ribonucleotide reductase M1 levels in the majority of human PDAC tumors when compared with normal. Delineation of the signaling pathway revealed that Pak1 confers resistance to gemcitabine by preventing DNA damage, inhibiting apoptosis and regulating survival signals via NF-κB. Furthermore, we found that Pak1 is an upstream interacting substrate of transforming growth factor β-activated kinase 1-a molecule implicated in gemcitabine resistance. Molecular mechanistic studies revealed that gemcitabine docks with the active site of Pak1; furthermore, gemcitabine treatment induces Pak1 kinase activity both in vivo and in cell-free system. Finally, results from athymic mouse tumor models illustrated that Pak1 inhibition by IPA-3 enhances the cytotoxicity of gemcitabine and brings about pancreatic tumor regression.

CONCLUSION

To our knowledge, this is the first study illustrating the mechanistic role of Pak1 in causing gemcitabine resistance via multiple signaling crosstalks, and hence Pak1-specific inhibitors will prove to be a better adjuvant with existing chemotherapy modality for PDAC.

Transition from Reconstruction toward Thin Film on the (110) Surface of Strontium Titanate

The surfaces of metal oxides often are reconstructed with a geometry and composition that is considerably different from a simple termination of the bulk. Such structures can also be viewed as ultrathin films, epitaxed on a substrate. Here, the reconstructions of the SrTiO3 (110) surface are studied combining scanning tunneling microscopy (STM), transmission electron diffraction, and X-ray absorption spectroscopy (XAS), and analyzed with density functional theory calculations. Whereas SrTiO3 (110) invariably terminates with an overlayer of titania, with increasing density its structure switches from n × 1 to 2 × n. At the same time the coordination of the Ti atoms changes from a network of corner-sharing tetrahedra to a double layer of edge-shared octahedra with bridging units of octahedrally coordinated strontium. This transition from the n × 1 to 2 × n reconstructions is a transition from a pseudomorphically stabilized tetrahedral network toward an octahedral titania thin film with stress-relief from octahedral strontia units at the surface.

False-positive hepatitis C virus serology after placement of a ventricular assistance device

BACKGROUND

Ventricular assist devices (VADs) have been associated with immune activation and sensitization. We observed several cases of false-positive (FP) hepatitis C virus (HCV) antibody (Ab) tests in patients being evaluated for orthotopic heart transplant (OHT), prompting us to investigate this further.

METHODS

We reviewed all VAD and OHT cases at Johns Hopkins from 2005 to 2012. FP HCV serology was defined as an equivocal or low-positive HCV Ab, plus either (i) a negative recombinant immunoblot (RIBA) and/or HCV nucleic acid test (NAT), or (ii) an indeterminate RIBA and negative NAT.

RESULTS

In 53 patients with available HCV testing, nearly 40% of patients (21/53: 39.6%) developed FP HCV Ab tests after VAD placement: 4 patients had negative NAT, 12 had negative RIBA, and 5 had an indeterminate RIBA and negative NAT. All patients with indeterminate RIBA tests had isolated reactivity to the same HCV protein, c100p/5-1-1p (NS4b protein). In 3 of 4 VAD patients who had OHT and repeat HCV Ab testing after VAD removal, repeat HCV Ab was negative (699-947 days after OHT); in 1 case, FP HCV serology persisted (5 days after OHT). Thirteen patients had OHT alone and none developed a FP HCV Ab.

CONCLUSIONS

FP HCV Ab results following VAD placement are very common. Reversal of FP serology in several patients after VAD removal is suggestive of a possible association with the VAD hardware. Clinicians should be aware of this phenomenon, as it could lead to delays in determining eligibility for OHT and increased costs.

Dependence of Young's modulus on the sodium content within the structural tunnels of a one-dimensional Na-ion battery cathode

We report on the Young's modulus (YM) of single-crystalline Na4Mn9O18 (or Na0.44MnO2) nanowires (NWs), which have shown promise as reversible sodium-ion (Na(+)) intercalation cathodes with high capacity and excellent cyclability. In addition, acid treatment of this material yielded proton stabilized Na(0.44-y)MnO2 (y ∼ 0.23) NWs with a 74% increase in the YM. The tight correlation between YM and ionic content within the crystalline tunnels is particularly significant, since it points to the strong dependence of elastic properties on state-of-charge (SOC) within battery materials.

Reversal of loop ileostomy under an Enhanced Recovery Programme - Is the stapled anastomosis technique still better than the handsewn technique?

INTRODUCTION

Recent literature suggests that stapled anastomotic (SA) technique for the reversal of loop ileostomy (LI) may be beneficial in terms of early recovery and reduced incidence of small bowel obstruction when compared to the handsewn anastomosis (HA). Enhanced Recovery Programme (ERP) after colorectal procedures has demonstrated a reduction in some aspects of surgical morbidity. The aim of this study was to investigate the outcomes of patients undergoing reversal of LI within an ERP programme and compare the HA to the SA in relation to clinical outcomes.

MATERIAL AND METHODS

All adult patients undergoing elective reversal of loop ileostomy between January 2008 and December 2012 without any additional procedures, were included in our study. Adherence to ERP modules and 30 day postoperative complications were assessed via retrospective review of patient case notes.

RESULTS

One hundred and eight patients had an ileostomy reversal; 61 in the SA and 47 in the HA group. There were no demographic differences between the two groups. ERP module compliance was satisfactory (>80%) in 11 of the 14 modules with no difference in individual module compliance between the two groups. The operating times were found to be comparable (p = 0.35). Overall mortality (p = 0.44), anastomotic leak rates (p = 1.00), intra-abdominal collections (p = 0.65), small bowel obstruction (p = 1.00), reoperation rates (p = 0.65), ileus (p = 0.14) and other significant complications (Clavien-Dindo > 2) (p = 0.08) were similar between the two groups. A significantly longer total length of hospital stay (TLOS) was found in the SA group (median 3 Vs 4 days, p = 0.009).

CONCLUSION

Reversal of LI under an ERP appears to potentially neutralise the suggested SA benefits in terms of postoperative complications without any additional negative implications. Other non-operative factors may have a potential effect on outcomes such as the TLOS.

Single nanowire manipulation within dielectrophoretic force fields in the sub-crossover frequency regime

This paper presents the quantitative relationship between the control parameters of a dielectrophoretic (DEP) force field and the resulting electrokinetic region of influence experienced by individual nanowires (NWs) in colloidal suspensions. Our results show that DEP operation at sub-crossover frequencies, which are defined as frequencies slightly below the transition from positive-to-negative DEP, offers a suitable but previously unexplored performance regime for single NW manipulation and assembly. The low-magnitude DEP forces at these frequencies, which are estimated to be 8 orders of magnitude smaller as compared to near-DC frequencies, provide an efficient avenue to controllably extend electrokinetic influence on suspension volumes that present isolated NWs. These results are demonstrated using α-phase manganese dioxide NWs as a model one-dimensional construct. Based on experimentally extracted values for the NW intrinsic conductivity and dielectric permittivity, we employ computational models to explain each of the performance regimes observed in this nanoassembly system. In addition, we use a new approach to estimate the concentration of a NW suspension from experimentally observed data for deposition yields.

On-chip lithium cells for electrical and structural characterization of single nanowire electrodes

We present a transmission electron microscopy (TEM)-compatible, hybrid nanomachined, on-chip construct for probing the structural and electrical changes in individual nanowire electrodes during lithium insertion. We have assembled arrays of individual β-phase manganese dioxide (β-MnO2) nanowires (NWs), which are employed as a model material system, into functional electrochemical cells through a combination of bottom-up (dielectrophoresis) and top-down (silicon nanomachining) unit processes. The on-chip NWs are electrochemically lithiated inside a helium-filled glovebox and their electrical conductivity is studied as a function of incremental lithium loading during initial lithiation. We observe a dramatic reduction in NW conductivity (on the order of two to three orders in magnitude), which is not reversed when the lithium is extracted from the nanoelectrode. This conductivity change is attributed to an increase in lattice disorder within the material, which is observed from TEM images of the lithiated NWs. Furthermore, electron energy loss spectroscopy (EELS) was employed to confirm the reduction in valence state of manganese, which occurs due to the transformation of MnO2 to LixMnO2.

Epidemiology, risk factors, and outcomes of Clostridium difficile infection in kidney transplant recipients

BACKGROUND

We sought to describe the epidemiology and risk factors for Clostridium difficile infection (CDI) among kidney transplant recipients (KTR) between 1 January 2008 and 31 December 2010.

METHODS

A single-institution retrospective study was conducted among all adult KTR with CDI, defined as a positive test for C. difficile by a cell cytotoxic assay for C. difficile toxin A or B or polymerase chain reaction test for toxigenic C. difficile.

RESULTS

Among 603 kidney transplants performed between 1 January 2008 and 31 December 2010, 37 (6.1%) patients developed CDI: 12 (of 128; 9.4%) high-risk (blood group incompatible and/or anti-human leukocyte antigen donor-specific antibodies) vs. 25 (of 475; 5.3%, P = 0.08) standard-risk patients. The overall rate of CDI increased from 3.7% in 2008 to 9.4% in 2010 (P = 0.05). The median time to CDI diagnosis was 9 days, with 27 (73.0%) patients developing CDI within the first 30 days after their transplant, and 14 (51.8%) developing CDI within 7 days. A case-control analysis of 37 CDI cases and 74 matched controls demonstrated the following predictors for CDI among KTR: vancomycin-resistant Enterococcus colonization before transplant (odds ratio [OR]: 3.6, P = 0.03), receipt of an organ from Centers for Disease Control high-risk donor (OR: 5.9, P = 0.006), and administration of high-risk antibiotics within 30 days post transplant (OR: 6.6, P = 0.001).

CONCLUSIONS

CDI remains a common early complication in KTR, with rates steadily increasing during the study period. Host and transplant-related factors and exposure to antibiotics appeared to significantly impact the risk for CDI among KTR.

Follicular and endocrinological turnover associated with GnRH induced follicular wave synchronization in Indian crossbred cows

The goal of this study was to record the hormonal and follicular turnover in Jersey crossbred cows when subjected for follicular wave synchronization using GnRH. Six healthy, non-lactating and regularly cycling Jersey crossbred cows (5-6 y) were used for the study. In the control group, the follicular wave pattern was ultrasonographically investigated in 18 cycles (3 cycles/cow). In the treatment group, GnRH analogue (buserelin acetate 10 μg im) was administered on Day 6 of the cycle and follicular wave pattern was studied in 12 cycles (2 cycles/animal). Follicular population was categorized based on their diameter Class I, ≤5 mm; Class II, >5-<9 mm; Class III, ≥9 mm) and the number of follicles in each category was determined on Day 6, Day 8 and Day 10. Plasma FSH and progesterone concentrations were estimated in both control and treatment groups. Out of 18 estrous cycles studied, 14 cycles (77.8%), three cycles (16.7%) and one cycle (5.6%) exhibited three-, two- and four-follicular waves per cycle, respectively. It was evident that the DF of Wave I established its dominance and was in the growing phase by Day 6 of the estrous cycle in all the normally cycling crossbred cows. The DF ovulated in all the animals (100%) in the mean interval of 27.7 ± 0.2 h after GnRH administration. A synchronized homogenous group of follicles emerged two days after GnRH injection (Day of 8.0 ± 0.0) in all the animals (100%). The combination of LH surge induced ovulation of DF (abrupt termination of Wave I) and FSH surge stimulated homogenous recruitment of Class I follicles, led to a synchronized emergence of follicular wave. All the GnRH treated cows had three follicular waves because of early emergence and short period of dominance of Wave II DF.

Temporary vascular shunts

Temporary vascular shunts have been used for nearly 100 years in patients. Originally, they were used as vascular grafts that were likely to thrombose as collaterals would hopefully develop. More recently, they have been used as a device to be replaced by a permanent vascular graft during the same operation or at a reoperation. Indications for the use of shunts are a "damage control" procedure for a peripheral or truncal vascular injury, Gustilo IIIC fracture of an extremity, need for perfusion as a complex revascularization is performed, and planned replantation of a hand, forearm, or arm. They are used in approximately 8% of vascular injuries treated in urban trauma centers in the United States and have an excellent patency rate without heparinization.

Donor-derived organ transplant transmission of coccidioidomycosis

Coccidioidomycosis in solid organ transplant recipients most often occurs as a result of primary infection or reactivation of latent infection. Herein, we report a series of cases of transplant-related transmission of coccidioidomycosis from a single donor from a non-endemic region whose organs were transplanted to 5 different recipients. In all, 3 of the 5 recipients developed evidence of Coccidioides infection, 2 of whom had disseminated disease. The degree of T-cell immunosuppression and timing of antifungal therapy initiation likely contributed to development of disease and disease severity in these recipients. This case series highlights the importance of having a high index of suspicion for Coccidioides infection in solid organ transplant recipients, even if the donor does not have known exposure, given the difficulties of obtaining a detailed and accurate travel history from next-of-kin.

Outcome analysis of trapezectomy with and without pyrocarbon interposition to treat primary arthrosis of the trapeziometacarpal joint

We performed a prospective cohort comparative analysis of simple trapezectomy and trapezectomy with pyrocarbon interposition in 38 consecutive patients with trapeziometacarpal joint osteoarthrosis. Patients were assessed preoperatively, at six and 12 months postoperatively using subjective and objective tools. Subjective assessment was performed using the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire and the visual analogue score. Objective assessment was performed with grip strength measurements. At each time interval, statistical differences were sought between the two subgroups. No significant difference between the two subgroups was noted at any time interval on subjective or objective assessment. A significant difference (p < 0.05) was found on comparing the respective preoperative and 12-month subjective scores in both subgroups. Of the pyrocarbon subgroup seven had related complications. We suggest that pyrocarbon interposition does not significantly improve postoperative function, requires a longer operation with a high postoperative risk of pyrocarbon displacement and need for revision surgery.