Use of a tissue expander as a radio-protective spacer with a latissimus dorsi flap in the management of a peripheral primitive neuroectodermal tumour (pPNET)

Peripheral primitive neuroectodermal tumours (pPNET) are aggressive neoplasms that require radical surgical resection with adjuvant chemotherapy and radiotherapy. A pPNET of the posterior chest wall was resected with wide soft tissue margins in a 14 year old male. Following tumour excision a spacer device was positioned in the retroperitoneum adjacent to the ipsilateral left kidney displacing it from the planned radiotherapy field. A pedicled latissimus dorsi myocutaneous flap was used to achieve robust soft tissue cover. Ultrasound demonstrated anteromedial displacement of the left kidney with no hydronephrosis and renal function remained normal during subsequent radiotherapy. This report highlights the usefulness of a tissue expander in providing protection for vital structures during radiotherapy.

Plasma total homocysteine is not associated with peripheral neuropathy in a groups Bangladeshi type 2 diabetic subjects

Aims: The present study was undertaken to explore the relationship of plasma homocysteine in the pathogenesis of neuropathy in diabetic patients.Subjects and Methods: Forty two type 2 diabetic patients [22 with neuropathy (DN group) and 20 without neuropathy (DNN group)], age range between 35-70 years had relatively controlled glycemia and duration of diabetes 7-15 years, were studied. Motor and sensory nerve conduction velocities and action potential amplitudes of peripheral nerves were determined by following standard protocol. HbA1c was estimated by modified HPLC (BIO-RAD Variant, USA). Serum C-peptide was measured by enzyme linked immunosorbentassay (ELISA), plasma total homocysteine by Fluorescent Polarization Immunoassay (FPIA). Results: Age, BMI and blood pressure of the study subjects were. Duration of diabetes between DN and DNN groups was comparable. DN group had significantly higher fasting glucose levels (9.8±3.8, mmol/l) compared to the DNN group (6.9±1.8, p=0.004). This trend was also reflected in the HbA1c level: 8.7± 2.1 vs 7.2±1.6 in DN group and DNN group respectively (p=0.009). The two diabetic groups had relatively higher absolute C-peptide level compared to the controls (p=ns). DN and DNN groups had significantly higher plasma homocysteine level compared to the Controls. But between the two diabetic groups no significant difference was observed. Ulnar and peroneal motor nerve conduction velocities and compound muscle action potentials in the diabetic neuropathy group significantly lower compared to diabetic counterpart and the controls. Ulnar and sural sensory nerve conduction velocities and action potentials were significantly lower in the diabetic neuropathy group compared to the diabetic counterpart and the controls. Plasma homocysteine did not show any correlation with nerve conduction velocities  and action potential amplitudes.Conclusions: The data concluded that (i) Diabetic neuropathy may not  be related to hyperhomocysteinemia in type 2 diabetic patients of Bangladeshi origin; (ii) Hyperglycemia, even at milder level, is related to neuronal dysfunction in these subjects; and (ii) Hyperinsulinemia don't seem to be prerequisite for neuropathy in these subjects. DOI: http://dx.doi.org/10.3329/bjms.v11i4.12607 Bangladesh Journal of Medical Science Vol. 11 No. 04 Oct’12  

Contractility of ventricular myocytes is well preserved despite altered mechanisms of Ca2+ transport and a changing pattern of mRNA in aged type 2 Zucker diabetic fatty rat heart

There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The objective of the study was to investigate ventricular myocyte shortening, intracellular Ca(2+) signalling and expression of genes encoding cardiac muscle proteins in the aged Zucker diabetic fatty (ZDF) rat. There was a fourfold elevation in non-fasting blood glucose in ZDF rats (478.43 ± 29.22 mg/dl) compared to controls (108.22 ± 2.52 mg/dl). Amplitude of shortening, time to peak (TPK) and time to half (THALF) relaxation of shortening were unaltered in ZDF myocytes compared to age-matched controls. Amplitude and THALF decay of the Ca(2+) transient were unaltered; however, TPK Ca(2+) transient was prolonged in ZDF myocytes (70.0 ± 3.2 ms) compared to controls (58.4 ± 2.3 ms). Amplitude of the L-type Ca(2+) current was reduced across a wide range of test potentials (-30 to +40 mV) in ZDF myocytes compared to controls. Sarcoplasmic reticulum Ca(2+) content was unaltered in ZDF myocytes compared to controls. Expression of genes encoding cardiac muscle proteins, membrane Ca(2+) channels, and cell membrane ion transport and intracellular Ca(2+) transport proteins were variously altered. Myh6, Tnnt2, Cacna2d3, Slc9a1, and Atp2a2 were downregulated while Myl2, Cacna1g, Cacna1h, and Atp2a1 were upregulated in ZDF ventricle compared to controls. The results of this study have demonstrated that preserved ventricular myocyte shortening is associated with altered mechanisms of Ca(2+) transport and a changing pattern of genes encoding a variety of Ca(2+) signalling and cardiac muscle proteins in aged ZDF rat.

Low Temperature ECR -Plasma Assisted MOCVD Microcrystalline and Amorphous GaN Deposition and Characterization for Electronic Devices

GaN films have been deposited over a range of temperatures from 50 C to 650 C by ECR plasma MOCVD on silicon (111) and (100), sapphire and quartz using triethylgallium and molecular nitrogen or ammonia as reagents. Growth rates of 2 um/hr are achieved on temperature-controlled substrates (total reactor pressure 0.5 mTorr, 250 watts at 2.45 GHz).

Films deposited at 200, 600 and 650 C on sapphire show the GaN(0002) diffraction peak and sharp photoluminescence lines (at 10 K) between 370 and 400 nm and broad emission at 530-550 nm. Broad photoluminescence at 390 nm is observed from GaN/Si( 11). Films deposited at 50 and 100 C show no evidence of a crystalline phase or GaN(0002) diffraction peak. The films are smooth and optically transparent. A broad photoluminescence peak at 520 nm, with a fwhm of about 150 nm is also observed (at 10K). The optical bandgap is measured to be about 2.6-2.7 eV. All of these films show a GaN LO phonon mode at 736 cm-l. IR spectra indicate some hydrocarbon impurities in the low temperature films.

Prototype devices (Schottky barrier diodes) have been made from MOCVD GaN and amorphous GaN.

Workplace-related burns

Introduction. The key element of a safe workplace for employees is the maintenance of fire safety. Thermal, chemical, and electrical burns are common types of burns at the workplace. This study assessed the epidemiology of work-related burn injuries on the basis of the workers treated in a regional burn centre. Methods. Two years' retrospective data (2005-2006) from the Trauma Registry of the American College of Surgeons of the Joseph M. Still Burn Center at Doctors Hospital in Augusta, Georgia, were collected and analysed. Results. During the time period studied, 2510 adult patients with acute burns were admitted; 384 cases (15%) were work-related. The average age of the patients was 37 yr (range, 15-72 yr). Males constituted the majority (90%) of workrelated burn injury admissions. The racial distribution was in accordance with the Centre's admission census. Industrial plant explosions accounted for the highest number of work-related burns and, relatively, a significant number of patients had chemical burns. The average length of hospital stay was 5.54 days. Only three patients did not have health insurance and four patients (1%) died. Conclusion. Burn injuries at the workplace predominantly occur among young male workers, and the study has shown that chemical burns are relatively frequent. This study functions as the basis for the evaluation of work-related burns and identification of the causes of these injuries to formulate adequate safety measures, especially for young, male employees working with chemicals.

Quaternary ultraviolet AlInGaN MQW laser diode performance using quaternary AlInGaN electron blocking layer

The effect of polarization-matched Al(0.25)In(0.08)Ga(0.67)N electron-blocking layer (EBL) on the optical performance of ultraviolet Al(0.08)In(0.08)Ga(0.84)N/Al(0.1)In(0.01)Ga(0.84)N multi-quantum well (MQW) laser diodes (LDs) was investigated. The polarization-matched Al(0.25)In(0.08)Ga(0.67)N electron blocking layer (EBL) was employed in an attempt to reduce the polarization effect inside the active region of the diodes. The device performance which is affected by piezoelectric was studied via drift-diffusion model for carrier transport, optical gain and losses using the simulation program of Integrated System Engineering Technical Computer Aided design (ISE TCAD). The optical performance of the LD using quaternary Al(0.25)In(0.08)Ga(0.67)N EBL was compared with the LD using ternary Al(0.3)Ga(0.7)N EBL where both materials have the same energy band gap of Eg = 3.53 eV. The self-consistent ISE-TCAD simulation program results showed that the polarization-matched quaternary Al(0.25)In(0.08)Ga(0.67)N EBL is beneficial as it confines the electrons inside the quantum well region better than ternary Al(0.3)Ga(0.7)N EBL. The results indicated that the use of Al(0.25)In(0.08)Ga(0.67)N EBL has lower threshold current and higher optical intensity than those for Al(0.3)Ga(0.7)N EBL. The effect of Al(0.25)In(0.08)Ga(0.67)N EBL thickness on the performance of LDs has also been studied. Results at room temperature indicated that lower threshold current, high slope efficiency, high output power, and high differential quantum efficiency DQE occurred when the thickness of Al(0.25)In(0.08)Ga(0.67)N EBL was 0.25 µm.

Changing pattern of gene expression is associated with ventricular myocyte dysfunction and altered mechanisms of Ca2+ signalling in young type 2 Zucker diabetic fatty rat heart

The association between type 2 diabetes and obesity is very strong, and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The aim of this study was to investigate early changes in the pattern of genes encoding cardiac muscle regulatory proteins and associated changes in ventricular myocyte contraction and Ca(2+) transport in young (9- to 13-week-old) type 2 Zucker diabetic fatty (ZDF) rats. The amplitude of myocyte shortening was unaltered; however, time-to-peak shortening and time to half-relaxation of shortening were prolonged in ZDF myocytes (163 ± 5 and 127 ± 7 ms, respectively) compared with age-matched control rats (136 ± 5 and 103 ± 4 ms, respectively). The amplitude of the Ca(2+) transient was unaltered; however, time-to-peak Ca(2+) transient was prolonged in ZDF myocytes (66.9 ± 2.6 ms) compared with control myocytes (57.6 ± 2.3 ms). The L-type Ca(2+) current was reduced, and inactivation was prolonged over a range of test potentials in ZDF myocytes. At 0 mV, the density of L-type Ca(2+) current was 1.19 ± 0.28 pA pF(-1) in ZDF myocytes compared with 2.42 ± 0.40 pA pF(-1) in control myocytes. Sarcoplasmic reticulum Ca(2+) content, release and uptake and myofilament sensitivity to Ca(2+) were unaltered in ZDF myocytes compared with control myocytes. Expression of genes encoding various L-type Ca(2+) channel proteins (Cacna1c, Cacna1g, Cacna1h and Cacna2d1) and cardiac muscle proteins (Myh7) were upregulated, and genes encoding intracellular Ca(2+) transport regulatory proteins (Atp2a2 and Calm1) and some cardiac muscle proteins (Myh6, Myl2, Actc1, Tnni3, Tnn2, and Tnnc1) were downregulated in ZDF heart compared with control heart. A change in the expression of genes encoding myosin heavy chain and L-type Ca(2+) channel proteins might partly underlie alterations in the time course of contraction and Ca(2+) transients in ventricular myocytes from ZDF rats.

Surface phonon polariton characteristics of In(0.04)Al(0.06)Ga(0.90)N/AlN/Al(2)O(3) heterostructure

Surface phonon polariton (SPP) characteristics of In(0.04)Al(0.06)Ga(0.90)N/AlN/Al(2)O(3) heterostructure are investigated by means of p-polarized infrared (IR) attenuated total reflection spectroscopy. Two absorption dips corresponding to In(0.04)Al(0.06)Ga(0.90)N SPP modes are observed. In addition, two prominent dips and one relatively weak and broad dip corresponding to the Al(2)O(3) SPP mode, In(0.04)Al(0.06)Ga(0.90)N/Al(2)O(3) interface mode, and Al(2)O(3) bulk polariton mode, respectively, are clearly seen. No surface mode feature originating from the AlN layer is observed because it is too thin. Overall, the observations are in good agreement with the theoretical predictions.

Abstract 2163: Global gene expression profiles of the Egyptian hepatocellular carcinoma associated with HCV-Genotype-4

Background: Hepatocellular carcinoma (HCC) is a preventable disease rather than a curable one, since there is no well-documented effective treatment modality until now, making the molecular study of this disease mandatory.

Methods: Forty cases of HCV genotype 4-associated HCC patients from Egypt were studied for gene expression profile by 41 K c-DNA microarray.

Result: Out of the 41,000 genes, 958 were differentially expressed; 503 were up regulated (58 genes are involved in 65 different pathways) and 455 were down regulated (49 genes are involved in 59 different pathways). Only 19 pathways were specifically up regulated by 27 genes (ABCB10, ABCG2, RXRA, PRKAB2, IKBKG, ELOVL2, RAF1, ATP6V1A, FLJ21865, GUSB, IL7, EPO, CD1B, FGFR1, PDPK1, KPS6KB1, NOTCH4, CDK7, MNAT1, PRKACB, RXRA, PRKACB, ACCN1, RPS6KB1, BMP8A, SMAD6, CYCLIN E2) and 13 pathways are specifically down regulated by 19 genes (ARHGEF2,WASL, BACE1, A2M, PPP3CA, SLC1A, ITGAV, NRXN2, NCAM1, PER1, PIGX, ST3GAL2, ST3GAL4, DGKQ, ATG5, ENPEP, POLR2B, LTA). Sixty seven genes showed significant difference in their expression between HCC cases with and without cirrhosis. Confirmation of array data by RT-PCR was performed on a subset of genes (PPP3CA [75%], ATG-5 [85%], BACE [62%] which showed down regulation and ABCG2 [90%], RXRA [80%], ELOVL2 [65%], CXR3 [80%]) which showed up regulation.

Conclusion: This is the first study on the global gene expression profile in Egyptian HCC patients associated with HCV-Genotype-4 using the cDNA microarray. The identified genes could provide a panel of new prognostic and diagnostic markers for HCV- associated HCC. Also, our data identified some genes which are related to hepatic encephalopathy like ACCN1, BACE1, apoB, GABA-A AND ATG5 which could play an important role in the cross talk between liver and brain. They could also be used to identify candidate genes for molecular target therapy.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2163.

Burn Functional Outcomes - Ventilator Usage and Discharge Ambulation Status of Patients in a Burn Wound in-Patient Centre

Anticipating functional outcomes of patients managed in an in-patient burn wound centre can help in advising patients and their families of prognosis as well as assist case managers in discharge planning. The records of 37 burn patients were reviewed; one patient expired and was removed from further analysis. Data were obtained regarding patient characteristics, types and locations of burns and other wounds, ventilator use, level of mobility at hospital discharge, and disposition; three patients lacked discharge ambulation status and were removed from the outcome comparison analysis. Of the 36 patients, 17 had thermal burns and nine (25%) had associated inhalation injuries. Thermal burn patients (p = 0.02), patients requiring ventilator support during their hospital stay (p = 0.04), and those with inhalation injuries (p = 0.04) were less likely to be ambulating independently or with assistance at discharge from the burn wound centre than other patients. This preliminary study suggests that patients with thermal burns and inhalation injuries and those requiring ventilator support were less likely to be ambulatory at hospital discharge. Further studies appear indicated.

Presentation and survival of patients with AIDS-related Kaposi's sarcoma in Jos, Nigeria

AIDS-related Kaposi's sarcoma (AIDS-KS) remains a significant cause of morbidity and mortality. We describe the pattern of presentation and survival in Jos, Nigeria. We identified 48 HIV-positive patients with AIDS-KS and matched them for age and sex with an equal number of HIV-positive patients without AIDS-KS. We compared their clinical, immunological, virological characteristics and survival. They were similar in age and body mass index profile but patients with AIDS-KS had more tuberculosis co-infection (P, 0.02), lower median CD4 count (P, 0.003) and higher mortality (P, 0.002). Surprisingly, patients with AIDS-KS had lower levels of median viral load (29,347 copies/mL) compared with controls (80,533 copies/mL). We recommend specific AIDS-KS therapy in addition to highly active antiretroviral therapy in order to improve survival.