Do diabetic patients receiving conventional dialysis solutions benefit from peritoneal dialysis?

AIM

The study aimed to evaluate the impact of glucose-based peritoneal dialysis solutions (GBPDS) on diabetic patients on maintenance peritoneal dialysis.

METHODS

In this cross-sectional study we compared the influence of long term use of GBPDS on sixteen parameters related to the peritoneal glucose load, hydration status, inflammation, blood pressure, lipid profile and left ventricular mass in 45 stable PD patients (20 diabetic and 25 non-diabetic) receiving GBPDS.

RESULTS

At 24 months HbA1c, peritoneal glucose load index (PGLI), fluid overload (FO), plasma BNP, hsCRP and IL-6 levels, WBC count, blood pressure, triglycerides, LDL-C and left ventricular mass index (LVMI) were higher in diabetic patients compared to non-diabetic subjects (P ≤ 0.04). Of 16 tested variables, 14 had deteriorated at 24 months in diabetic patients. PGLI values > 3 g/kg/day or FO > 1.0 L were associated with abnormal values of HbA1c, plasma BNP, CRP and plasma IL-6 levels. 60% of diabetic patients had PGLI > 3g/kg/day compared to 32% of non-diabetic patients (P < 0.001). Seventy per cent of diabetic patients had FO > 1.0 L compared to 28% of non-diabetic patients (P < 0.001). Only 12% of diabetic patients had nocturnal blood pressure dipping compared to 45% of non-diabetics (P = 0.03). 57.8% of the studied patients had increased LVMI. Diabetic patients had higher LVMI values compared to non-diabetics (P < 0.001). The presence of DM was found to be the most powerful predictor for the development of LVH (P < 0.001).

CONCLUSION

Utilization of GBPDS in diabetic PD patients may be associated with substantial adverse consequences affecting glycemic control, hydration status, lipid profile, inflammation, blood pressure control and LVM.

Dihedron dielectric loaded surface plasmon athermal polarization converter

We investigate numerically a novel plasmonic polarization converter relying on the excitation of a so-called dihedron dielectric loaded plasmon polariton. The dihedron dielectric loaded waveguide consists of a dielectric ridge implemented at the inner corner of a metal-coated dielectric step. For a dielectric ridge with a square cross section, the plasmon polariton modes supported by each side of the metallized step hybridize to create supermodes with crossed polarizations. We show that the two supermodes can be operated in a dual-mode interferometer configuration to perform an efficient (24 dB) TE-TM/TM-TE polarization conversion over typical distances below 30 μm at telecommunications wavelengths. In addition, on the basis of the thermo-optical properties of our device, we find that the dihedron plasmonic polarization converter is temperature insensitive.

Nanosecond thermo-optical dynamics of polymer loaded plasmonic waveguides

The thermo-optical dynamics of polymer loaded surface plasmon waveguide (PLSPPW) based devices photo-thermally excited in the nanosecond regime is investigated. We demonstrate thermo-absorption of PLSPPW modes mediated by the temperature-dependent ohmic losses of the metal and the thermally controlled field distribution of the plasmon mode within the metal. For a PLSPPW excited by sub-nanosecond long pulses, we find that the thermo-absorption process leads to modulation depths up to 50% and features an activation time around 2 ns whereas the relaxation time is around 800 ns, four-fold smaller than the cooling time of the metal film itself. Next, we observe the photo-thermal activation of PLSPPW racetrack shaped resonators at a time scale of 300 ns followed however by a long cooling time (18 μs) attributed to the poor heat diffusivity of the polymer. We conclude that nanosecond excitation combined to high thermal diffusivity materials opens the way to high speed thermo-optical plasmonic devices.

Photo-thermal modulation of surface plasmon polariton propagation at telecommunication wavelengths

We report on photo-thermal modulation of thin film surface plasmon polaritons (SPP) excited at telecom wavelengths and traveling at a gold/air interface. By operating a modulated continuous-wave or a Q-switched nanosecond pump laser, we investigate the photo-thermally induced modulation of SPP propagation mediated by the temperature-dependent ohmic losses in the gold film. We use a fiber-to-fiber characterization set-up to measure accurately the modulation depth of the SPP signal under photo-thermal excitation. On the basis of these measurements, we extract the thermo-plasmonic coefficient of the SPP mode defined as the temperature derivative of the SPP damping constant. Next, we introduce a figure of merit which is relevant to characterize the impact of temperature onto the properties of bounded or weakly leaky SPP modes supported by a given metal at a given wavelength. By combining our measurements with tabulated values of the temperature-dependent imaginary part of gold dielectric function, we compute the thermo-optical coefficients (TOC) of gold at telecom wavelengths. Finally, we investigate a pulsed photo-thermal excitation of the SPP in the nanosecond regime. The experimental SPP depth of modulation obtained in this situation are found to be in fair agreement with the modulation depths computed by using our values of gold TOC.

Abstract 361: Characterization of Lipoproteins in the Hypertriglyceridemic Fredrickson-Levy Dyslipidemic Phenotypes with Chylomicrons: The Very Large Database of Lipids (VLDL-7)

Background

The major dyslipidemia (DL) classes (I-V) are relatively rare with limited phenotypic characterization across large populations.

Methods

We studied 1,340,614 U.S. adults from the Very Large Database of Lipids and identified those with chylomicron (CM) excess (types I and V). Lipid testing was by ultracentrifugation (VAP, Atherotech, Birmingham, AL). The distributions of total cholesterol (TC), HDL-C, LDL-C and triglycerides (TG) in the database were superimposable with those in the NHANES 2007-2008 survey. We used the following criteria to classify the excess lipoprotein components of DL in subjects with TG >130 mg/dL: CM defined by TG/Total cholesterol (TC) ratio > 9 only (Type I) and CM with >90th percentile VLDL-C (Type V). Subjects with types II, III, or IV DL were excluded.

Results

Type I DL was characterized by very high TG and very low HDL-C, LDLr-C, non-HDL-C and normal VLDL-C and RLP-C. Type V was characterized by TG approximately twice that of type I, low HDL-C and LDLr-C, and elevated VLDL-C, RLP-C and non-HDL-C. The VLDL3-C/IDL-C ratio was approximately 2, twice that of the non-CM groups (Table).

Summary

To our knowledge, this is the largest single report of subjects with these rare hyper-CM phenotypes. The findings support the mechanism of reduced CM clearance and impaired conversion of VLDL to IDL and LDL. The marked reduction in HDL-C is consistent with cholesterol ester transport protein mediated TG-Cholesterol ester exchange between CM and apoB100 lipoproteins.

Abstract 362: Characterization of Triglyceride-Rich Remnant Lipoproteins in the Hypertriglyceridemic Fredrickson-Levy Dyslipidemic Phenotypes without Chylomicrons: The Very Large Database of Lipids (VLDL-6)

Background

The major dyslipidemia (DL) classes are relatively rare with limited phenotypic characterization across large populations.

Methods

We studied 1,340,614 U.S. adults from the Very Large Database of Lipids. Lipid testing was by ultracentrifugation (VAP, Atherotech, Birmingham, AL). Distributions of total cholesterol (TC), HDL-C, LDL-C and triglycerides (TG) in the database were superimposable with those in the NHANES 2007-2008 survey. We used the following criteria to classify the excess lipoprotein components of DL in subjects with TG >130 mg/dL without chylomicrons (CM): VLDL-C or LDLr-C (directly measured LDL-C - Lp(a)-C -IDL-C) > 90 th percentile, Type III DL remnant lipoprotein cholesterol (RLP-C = VLDL3-C + IDL-C) excess by criterion of VLDL-C/TG > 0.3. The remaining subjects (continuum) not classified by DL criteria were further stratified by TG/HDL-C <3 vs. >3, associated with insulin resistance.

Results

VLDL3-C/ IDL-C ratio was approximately 1 across DL and the continuum groups. The highest concentration of RLP-C was in Type III DL; lesser RLP-C elevation is present in all DL characterized by VLDL excess. The highest non-HDL-C was present in type IIb with lesser elevations in types III and IV. RLP-C was higher in the TG/HDL-C>3 continuum than TG/HDL-C<3 continuum reference group (Table).

Summary

In addition to type III, the major non-CM DL is frequently associated with excess RLP-C. RLP-C tended to be normal in the continuum subjects, trending higher in those with TG/HDL-C>3.

Is routine hospital visit after day case inguinal hernia surgery in children necessary?

BACKGROUND

To observe the prospects of day case inguinal hernia surgery in children without routine postoperative hospital visits. The aim was to access the advantages, acceptability and safety of this change in practice in low resource country like Nepal.

METHODS

This was a cross-sectional study in a tertiary care general teaching hospital. Thirty children aged 6 months to 14 years who had elective day case Inguinal Hernia surgery from May 2011 to Oct 2011 were prospectively observed. Children with obstructed hernia, un-descended testis were excluded. Parents were counseled for omission of routine hospital visit after surgery. Main outcome measures were to observe unplanned hospital visit, reasons for visit, post-operative pain, wound infection and overall satisfaction of parents interviewed by telephone. Study was approved by institutional review committee.

RESULTS

There were 28 boys and two girls. Average age was five years. Right Inguinal Hernia patients were 19 in number while 11 patients had left sided hernia. None of the children visited health facility for pain or wound problem. Two children were brought to outpatient because they were mistakenly given appointment slip. Mother noticed recurrence and brought one child to surgical outpatient. All 30 parents responded to telephone enquiry and were satisfied.

CONCLUSIONS

Routine follow up visit after day care Inguinal Hernia surgery in children is not necessary. This practice is safe, economic and well accepted by children and parents.

Efficient photo-thermal activation of gold nanoparticle-doped polymer plasmonic switches

We report on the photo-thermal activation of dielectric loaded plasmonic switches comprised of gold nanoparticle-doped polymer deposited onto a gold film. The plasmonic switches rely on a multi-mode interferometer design and are fabricated by electron beam lithography applied to a positive resin doped with gold nanoparticles at a volume ratio of 0.52%. A cross-bar switching is obtained at telecom wavelengths by pumping the devices with a visible beam having a frequency within the localized surface plasmon resonance band of the embedded nanoparticles. By comparing the switching performances of doped and undoped devices, we show that for the modest doping level we consider, the power needed to activate the doped switches is reduced by a factor 2.5 compared to undoped devices. The minimization of activation power is attributed to enhanced light-heat conversion and optimized spatial heat generation for doped devices and not to a change of the thermo-optic coefficient of the doped polymer.

0.48Tb/s (12x40Gb/s) WDM transmission and high-quality thermo-optic switching in dielectric loaded plasmonics

We demonstrate Wavelength Division Multiplexed (WDM)-enabled transmission of 480Gb/s aggregate data traffic (12x40Gb/s) as well as high-quality 1x2 thermo-optic tuning in Dielectric-Loaded Surface Plasmon Polariton Waveguides (DLSPPWs). The WDM transmission characteristics have been verified through BER measurements by exploiting the heterointegration of a 60 μm-long straight DLSPPW on a Silicon-on-Insulator waveguide platform, showing error-free performance for six out of the twelve channels. High-quality thermo-optic tuning has been achieved by utilizing Cycloaliphatic-Acrylate-Polymer as an efficient thermo-optic polymer loading employed in a dual-resonator DLSPPW switching structure, yielding a 9 nm wavelength shift and extinction ratio values higher than 10 dB at both output ports when heated to 90°C.

Congenital kypho-scoliosis: a case of thoracic insufficiency syndrome and the limitations of treatment

INTRODUCTION

Congenital spinal vertebral anomalies may present with deformity resulting in congenital scoliosis and kyphosis. This leads to abnormal spinal growth. The latter when combined with associated rib fusions may impair normal thoracic cage development and resultant pulmonary hypoplasia. Most congenital scoliosis can be detected in utero by ultrasound scan or recognized in the neonatal period, but a few spinal defects can remain undetected.

MATERIALS AND METHODS

In this Grand Round, we present the case of a 7-year-old girl with a severe scoliosis and thoracic insufficiency syndrome (TIS). 3D CT reconstruction imaging demonstrated a mixed picture of fusion and segmentation abnormalities. A marked kyphoscoliosis was demonstrated at the thoraco-lumbar junction. Via a left thoracotomy, anterior excision of intervertebral discs was performed together with, interbody fusion, and in situ stabilisation of the kyphosis with double allograft (femur) strut grafts.

CONCLUSIONS

This article highlights the features of congenital kypho-scoliosis and TIS. The difficulties of treating kyphosis when combined with TIS are discussed together with the limitations of current surgical techniques.

A preliminary trial of the effect of recombinant human growth hormone on short-term linear growth and glucose homeostasis in children with Crohn's disease

BACKGROUND

It is unclear whether recombinant human growth hormone (rhGH) improves linear growth in children with Crohn's disease (CD).

AIMS

To investigate the effects of rhGH on height velocity (HV) and glucose homeostasis over a 6-month period.

DESIGN AND SETTING

Randomized controlled trial in two tertiary children's hospitals in 22 children with inflammatory bowel disease amongst whom 21 had CD. Duration of disease from diagnosis and number of acute relapses requiring either exclusive enteral nutrition or therapeutic dose of oral prednisolone were similar in the treatment and control groups.

INTERVENTION

Either rhGH (0·067 mg/kg per day) as daily subcutaneous injections (rhGH group; n, 11) or no rhGH, (Ctrl; n, 11) for 6 months.

MAIN OUTCOME MEASURE

Percentage change in HV after 6 months in the two groups. Auxology, puberty, skeletal age, disease factors, treatment and glucose homeostasis were also assessed.

RESULTS

Median HV increased from 4·5 (range, 0·6, 8·9) at baseline to 10·8 (6·1, 15·0) cm/year at 6 month (P = 0·003) in the rhGH group, whereas in the Ctrl group, it was 3·8 (1·4, 6·7) and 3·5 cm/year (2·0, 9·6), respectively (P = 0·58). Median percentage increase in HV after 6 months in the rhGH group was 140% (16·7, 916·7) compared with 17·4% (-42·1%, 97·7%) in the Ctrl group (P < 0·001). There were no significant differences in disease activity and proinflammatory cytokines at baseline and 6 months in both groups and change in bone age for chronological age was also similar in the two groups. In the rhGH group, fasting insulin increased from 4·0 (2·0, 11·0) to 7·0 mU/l (2·0, 16·0) (P = 0·02), whereas in the Ctrl group, it was 3·0 (1·2, 12·7) and 3·8 mU/l (2·1, 7·0) (P = 0·72), respectively.

CONCLUSIONS

Although this pilot trial shows that rhGH can improve short-term linear growth in children with CD, the clinical efficacy of this therapy needs to be further studied in longer-term studies of growth, glucose homeostasis and disease status.

Plasma Renin in ipsilateral renal vein in patients with chronic unilateral pelvic ureteric junction obstruction

Acute experimental hydronephrosis induces increased output of renin from ipsilateral kidney. In most clinical presentation of unilateral hydronephrosis the patients are however, normotensive with normal circulating plasma renin activity. In consideration of this argument we undertook this prospective study of ipsilateral renal vein renin activity in children with congenital Pelvic Ureteric Junction Obstruction (PUJO) and compared with other wise normal children. In this prospective cross-sectional study, started from July 99 to June 2001, twenty patients, age upto 12 years, with unilateral hydronephrosis and in control group ten patients without hydronephrosis were taken. 2ml blood was taken from the renal vein in study group and from infrarenal portion of inferior vena cava during exploratory laparotomy from the control group. All the patients had advanced grade of hydronephrosis and two patients (13%) had mild hypertension. In this study the mean plasma renin activity (PRA) was 45.58 ng/ml/hr (range: 11.69-67.56 ng/ml/hr) in study group. The mean PRA in control group was 5.9ng/ml/hr. The result of study group was significantly higher than normal (P value 0.0003). In Bangladesh we are doing more conservative kidney preserving surgery for PUJO, but need long term follow up of the patients undergoing surgery for PUJO in childhood for potential of developing renin-angiotensin induced hypertension in later life.

The growth hormone insulin-like growth factor 1 axis in children and adolescents with inflammatory bowel disease and growth retardation

CONTEXT

There is scarce knowledge about the growth hormone (GH) insulin-like growth factor-1 (IGF1) axis in children & adolescents with inflammatory bowel disease (IBD) and growth retardation.

OBJECTIVE

To describe the pattern of GH and IGF1 secretion in children & adolescents with IBD.

DESIGN

A retrospective review of 28 patients (23 M) of IBD (25 Crohn's Disease and three Ulcerative Colitis) and growth retardation who had investigation of the GH/IGF-1 axis. Height velocity (HV) and serum IGF1 were converted to standard deviation score (SDS); to account for delayed puberty in girls over 11 years and boys over 12 years, HV and serum IGF1 SDS were adjusted for bone age.

RESULTS

Median (range) age and Ht SDS at the time of endocrine evaluation was 14.3 years (7.7,17.0) and -2.0(-3.6,-0.9), respectively. Median HVSDS over the prior 12 months was -2.2(-7.7,2.8). Median peak serum GH on insulin tolerance test (ITT) was 5.8 mcg/l (1.3, 24.0), and median serum IGF1 SDS was -0.9(-3.1, 0.1). Five of 28 (18%) had a peak serum GH of >12 mcg/l. Overall, four had biochemical evidence of functional GH deficiency (peak GH < 3 mcg/l and IGF1 SDS < 0) and 11 children had biochemical evidence suggesting GH resistance (peak GH > 6 mcg/l and IGF1 SDS < 0). However, only one child had a peak serum GH > 6 mcg/l and a very low IGF1 SDS of <-2.0. There was a negative association between peak serum GH and Ht SDS (r = -0.49, P = 0.008), but there was no association with HV and there was no association between IGF1 SDS and Ht or HV SDS. IGF1 SDS showed a negative association with erythrocyte sedimentation rate (r = -0.41, P = 0.04).

CONCLUSION

Growth retardation in children and adolescents with IBD is commonly associated with a range of biochemical abnormalities ranging from functional GH deficiency to GH resistance. In these children, poor relationship between systemic markers of growth and height velocity point to an important role of growth factors at the target organ level in modulating growth in children with IBD. The value of assessing the GH/IGF-1 axis and whether it predicts subsequent response to growth-promoting therapy requires further exploration.

Acetabular surgical units: a directory for the United Kingdom

We present the first directory of the specialist acetabular surgical units throughout the United Kingdom. Previously there has not been any directory of acetabular surgeons in the UK as held by any governmental or healthcare agency. We have established that acetabular fracture fixation cases were performed at 33 NHS hospitals in the UK in 2003-2004. The total number of cases performed at each centre per year varied greatly (range 2-98). Twenty-one units performed greater than 10 cases per annum, comprising 92% of all operative cases in the UK in 2003-2004. We encourage trauma and orthopaedic units to communicate directly with their local units and familiarise themselves with those units' preferred referral processes. We publish this directory to assist in future research in this field, to help in resource planning in the field of major trauma, to aid training and continued development in this complex area and help with the timely referral of injured patients to these specialist units for this significant injury.

Kikuchi disease in a child

Kikuchi disease, also called histocytic necrotizing lymphadenitis or focal histiocytic lymphadenitis, is a rare, idiopathic and generally self limited cause of lymphadenitis. It was first described in 1972 in Japan. The most common clinical manifestation is cervical lymphadenopathy with or without systemic symptoms & signs. It almost always runs a benign course and resolves in several weeks to months.