Overcoming T. gondii infection and intracellular protein nanocapsules as biomaterials for ultrasonically controlled drug release.

One of the pivotal matters of concern in intracellular drug delivery is the preparation of biomaterials containing drugs that are compatible with the host target. Nanocapsules for oral delivery are found to be suitable candidates for targeting Toxoplasma gondii (T. gondii), a maneuvering and smart protozoic parasite found across Europe and America that causes a subtle but deadly infection. To overcome this disease, there is much potential of integrating protein-based cells into bioinspired nanocompartments such as via biodegradable cross-linked disulfide polyelectrolyte nanoparticles. The inner membrane vesicle system of these protein-drugs is not as simple as one might think. It is a complex transport network that includes sequential pathways, namely, endocytosis, exocytosis and autophagy. Unfortunately, the intracellular trafficking routes for nanoparticles in cells have not been extensively and intensively investigated. Hence, there lies the need to create robust protein nanocapsules for precise tracing and triggering of drug release to combat this protozoic disease. Protein nanocapsules have the advantage over other biomaterials due to their biocompatibility, use of natural ingredients, non-invasiveness, patient compliance, cost and time effectiveness. They also offer low maintenance, non-toxicity to healthy cells and a strictly defined route toward intracellular elimination through controlled drug delivery within the therapeutic window. This review covers the unprecedented opportunities that exist for constructing advanced nanocapsules to meet the growing needs arising from many therapeutic fields. Their versatile use includes therapeutic ultrasound for tumor imaging, recombinant DNA, ligand and functional group binding, the delivery of drugs and peptides via protein nanocapsules and polyelectrolytes, ultrasound-(US)-aided drug release through the gastrointestinal (GI) tract, and the recent progress in targeting tumor cells and a vast range of cancer therapies. This review also outlines the limitations of current technologies and the directions of future outlook.

Predictors of Non-adherence to Immunosuppressive Therapy in Asian Liver Transplant Recipients.

BACKGROUND: Adherence to immunosuppressive medications has been shown to affect post-transplant outcomes. We aimed to determine the level of adherence to immunosuppressive therapy in liver transplant (LT) recipients and to elucidate factors associated with it, as well as patient preferences on the dosing schedule. METHODS: LT recipients were recruited during transplant clinic follow-up. A validated Morisky 8-item questionnaire was completed by patients to assess their adherence to immunosuppressive therapy. Adherence was determined by the sum of the responses to the questionnaire. Low, medium, and high adherence were defined by a Morisky score of >2, 1 to 2, and 0, respectively. Data on the patient's socio-economic and clinical background, dosing schedule of immunosuppressant medications, and patient preferences were included in the questionnaire. RESULTS: A total of 107 LT recipients were approached and 75 completed the questionnaire. The majority of patients (48/74, 64.9%) preferred a once-daily medication regimen. The proportion of high adherence was 24/75 (32.0%), medium adherence was 51/75 (42.7%), and low adherence was 19/75 (25.3%). Multivariate analysis showed younger age and post-transplant duration >5 years as independent predictors for low adherence. Among low-adherence patients, 16/19 (84.2%) patients were on a twice-daily regimen, and, of these, 14/16 (87.5%) preferred their medications to be reduced to once daily. CONCLUSIONS: A significant proportion (68%) of LT recipients had low to moderate adherence to medications, with younger age and longer post-transplant duration of >5 years as independent predictors. Early identification of at-risk patients is essential to allow implementation of measures to improve adherence. Simplifying medication regimens to once daily is a potential way to improve adherence.

Bocavirus infection following paediatric liver transplantation.

HBoV is an emergent virus, which is frequently detected as a co-infective agent. However, it can cause disease on its own. It is associated with respiratory and diarrhoeal illness in children and adults, whether immunocompetent or immunocompromised. We report HBoV infection in a child post-liver transplantation, who presented with persistent fever and mild tachypnea, 3 weeks after a successful transplant. She recovered spontaneously with no graft dysfunction.

Two consecutive partial liver transplants in a patient with Classic Maple Syrup Urine Disease.

Maple syrup urine disease is caused by a deficiency in the branched chain ketoacid dehydrogenase (BCKAD) complex. This results in the accumulation of branched chain amino acids (BCAA) and branched chain ketoacids in the body. Even when aggressively treated with dietary restriction of BCAA, patients experience long term cognitive, neurological and psychosocial problems. Liver transplantation from deceased donors has been shown to be an effective modality in introducing adequate BCKAD activity, attaining a metabolic cure for patients. Here, we report the clinical course of the first known patient with classic MSUD who received two consecutive partial liver grafts from two different living non-carrier donors and his five year outcome posttransplant. We also show that despite the failure of the first liver graft, and initial acute cellular rejection of the second liver graft in our patient, his metabolic control remained good without metabolic decompensation.

Assessment effect of gamma radiation on the flight ability of the peach fruit fly, Bactrocera zonata (Saunders).

The sterile insect technique is one of the most methods of fruit flies control. Flight ability of the Peach Fruit Fly (PFF), Bactrocera zonata was conducted under laboratory conditions to evaluate the effect of gamma radiation on flight ability of PFF, B. zonata. Pupae of PFF, B. zonata, were irradiated in an air atmosphere at 24, 48 and 72 h before adult emergence with three doses of Cobalt 60 (10, 30 and 50 Gray) and tested against 6, 12 and 20 cm tube heights. Flight Ability Percentage (FAP) of PFF was carried out for newly emerged flies and six-days-old of adult flies. FAP of newly emerged-and six- days-old of adult flies was inversely proportional to the tube heights, doses of gamma rays and with progress the age of flies. The FAP value was significantly higher at 6 cm tube height, followed by 12 cm then 20 cm tube heights for all tested levels of gamma rays, respectively.

Vascular complications in pediatric liver transplantation; single-center experience from Singapore.

AIM: Vascular complications (VC) are a major cause of significant morbidity and mortality in pediatric liver transplantation (LT). We reviewed our series to study the evolution of vascular reconstructions and its effect on the incidence of VC after LT, particularly with regard to the portal vein (PV). METHODS: The medical records of 81 pediatric LT performed in 76 children (38 boys) from 1991 to 2010 in the National University Hospital, Singapore, were reviewed to identify VC pertaining to PV, hepatic artery (HA), and hepatic veins (HV) and to analyse the data for the entire series and in 2 consecutive cohorts: initial 40 LT (group 1) and subsequent 41 LT (group 2). Specific interventions in group 2 were characterized by surgical innovations for reconstruction of the difficult PV and routine use of Doppler ultrasound intraoperatively and postoperatively. RESULTS: The overall incidence of VC was 19.7% (n = 16) and individually HA thrombosis 4.9% (n = 4), HA stenosis 1.2% (n = 1), PV thrombosis 12.3% (n = 9), PV stenosis 1.2% (n = 1), and HV thrombosis 1.2% (n = 1). The overall 1- and 5-year survival rates in our series were 89% and 85%, respectively. The 1- and 5-year survival rates in patients with and without VC were 81.25% and 68.75% and 90.8% and 89.2%, respectively. The incidence of VC decreased from 27.5% in group 1 to 12.1% in group 2 (p = .08). The major contribution to this appears to be a decrease in PV complications from 17.5% in group 1 to 7.3% in group 2 (P = .1). The incidence of HA (3 vs 2) and HV (1 vs 0) complications was similar between the 2 groups. CONCLUSIONS: Vascular reconstructions in small recipients are technically challenging and associated with a learning curve. Application of meticulous techniques in general, surgical innovations to the difficult PV in particular and attention to postoperative monitoring contribute toward a major reduction in VC.

Unusual shunt for symptomatic portal vein thrombosis after liver transplantation - Clatworthy revisited.

PV thrombosis is not an uncommon occurrence following pediatric LT. Symptomatic PHT following PV thrombosis is treated medically, surgical portosystemic shunting (mesorex, splenorenal, and mesocaval) being reserved for refractory cases. A 10-yr-old boy suffered recurrent malena and hemorrhagic shock because of chronic PV thrombosis following LT nine yr ago (1999). Extensive work-up failed to localize the bleeding source. The liver function remained normal. Initial attempts at surgical shunts failed owing to thrombosis (mesocaval 2001, splenorenal, inferior mesenteric-left renal vein, splenic-left external iliac vein 2008). In this situation, we performed a Clatworthy shunt by anastomosing the divided lower end of the LCIV to the side of SMV. There was a single, large caliber anastomosis. Post-operatively, the malena stopped completely, and clinically, there was no lower limb edema or encephalopathy. Doppler USG revealed persistence of hepatopetal flow within the portal collaterals. Follow-up at two yr reveals stable hepatic function with a patent shunt. To the best of our knowledge, we are not aware of a Clatworthy shunt being performed in a transplant setting. We reviewed the literature pertaining to this shunt in non-transplant patients with PHT.

Academy of medicine, Singapore-Ministry of Health clinical practice guidelines: management of food allergy.

The Academy of Medicine, Singapore (AMS) and the Ministry of Health (MOH) publish clinical practice guidelines to provide doctors and patients in Singapore with evidence-based guidance on managing important medical conditions. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the AMS-MOH clinical practice guidelines on the Management of Food Allergy, for the information of readers of the Singapore Medical Journal. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Academy of Medicine website: http://www.ams.edu.sg/guidelines.asp#foodallergy. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.

Probiotic supplementation in the first 6 months of life in at risk Asian infants--effects on eczema and atopic sensitization at the age of 1 year.

BACKGROUND: The role of probiotics in allergy prevention remains uncertain but has been shown in some studies to have a possible protective effect on eczema. OBJECTIVE: We aimed to assess the effect of probiotic supplementation in the first 6 months of life on eczema and allergic sensitization at 1 year of age in Asian infants at risk of allergic disease. METHODS: A double-blind, placebo-controlled randomized clinical trial involving 253 infants with a family history of allergic disease was carried out. Infants received at least 60 mL of commercially available cow's milk formula with or without probiotic supplementation [Bifidobacterium longum (BL999) 1 x 10(7) colony forming unit (CFU)/g and Lactobacillus rhamnosus (LPR) 2 x 10(7) CFU/g] daily for the first 6 months. Clinical evaluation was performed at 1, 3, 6 and 12 months of age, with serum total IgE measurement and skin prick tests conducted at the 12-month visit. The primary and secondary end-points were eczema and allergen sensitization, respectively. RESULTS: The incidence of eczema in the probiotic (22%) group was similar to that in the placebo group (25%) (P=0.53). The median Scoring Atopic Dermatitis score at 12 months was 17.10 (9.74) in the probiotic group and 11.60 (8.40) in the placebo group (P=0.17). The prevalence of allergen sensitization showed no difference (probiotic=24% vs. placebo=19%, P=0.26). The total IgE geometric mean (95% confidence interval) was 18.76 (12.54-24.98) kU/L in the probiotic group and 23.13 (16.01-30.24) kU/L in the placebo group (P=0.15). Atopic eczema (with sensitization) in the probiotic (7.3%) group was comparable to the placebo group (5.8%) (P=0.86). CONCLUSION: Early life administration of a cow's milk formula supplemented with probiotics showed no effect on prevention of eczema or allergen sensitization in the first year of life in Asian infants at risk of allergic disease. Further work is needed to determine whether timing of supplementation, dose and probiotic strain are important considerations.

Liver transplantation in Singapore 1990-2004.

INTRODUCTION: Liver transplantation is the accepted standard of care for patients with hepatocellular carcinoma, decompensated liver cirrhosis, and acute liver failure. Since the first liver transplant done in Singapore in 1990, results have been improving. We review the overall results of liver transplantation over the last 15 years. METHODS: All transplant cases from 1990 to 2004 were reviewed retrospectively. RESULTS: 100 liver transplants were performed over the last 15 years; four in the first five years and 96 in the subsequent ten years. Overall one- and five-year survival rates were 80 percent and 78 percent, respectively. 44 were paediatric transplants, of which biliary atresia was the commonest indication for paediatric transplant. 56 were adult transplants of which hepatocellular carcinoma and decompensated hepatitis B cirrhosis were the commonest indications for adult transplant. Infection remained the commonest cause of mortality. CONCLUSION: The number of transplants carried out per year was small due to the low cadaveric donation rate, but the survival of liver transplant patients was comparable to well-established liver transplant centres.

Outcome of liver transplantation for children with liver disease.

INTRODUCTION: The advent of liver transplantation has revolutionised the outcome of children with both acute liver failure and chronic end-stage liver disease. The aim of this study was to review the outcome of all paediatric liver transplants performed since the National Liver Transplant Programme began in 1990. METHODS: A retrospective review of all paediatric liver transplants from 1990 to December 2004 was performed. RESULTS: 46 liver transplants were performed in 43 children, of whom 23 (53.3 percent) were female. Median age at transplant was 21 months (range 11 months to 14 years). The most common indication for liver transplant was biliary atresia (71.7 percent). Living-related transplants accounted for 63 percent (29). Re-transplant rate was 6.5 percent with allograft loss as a result of hepatic artery thrombosis (two) and hepatic vein thrombosis (one). Tacrolimus was the primary immunosuppressive agent used in 89 percent of patients, with a 19.6 percent incidence of acute allograft rejection within the first six months. There were nine deaths. They were related to portal vein thrombosis (three), chronic rejection (one), sepsis (two), post-transplant lymphoproliferative disease (two) and primary graft non-function (one). Overall actuarial one- and five-year survival rate was 85.7 percent and 81.8 percent, respectively. CONCLUSION: Liver transplantation is an established form of intervention for end-stage liver disease and a variety of liver-related metabolic disease. Our results are comparable to those of well-established liver transplant centres.

Referral patterns and waiting times for liver transplantation in Singapore.

INTRODUCTION: Referral patterns, waiting times, waiting list, and mortality provide information on how effectively a transplant programme deals with referred patients. This paper aims to review these parameters in the Singapore National Liver Transplant Programme. METHODS: Data of all patients referred to the Singapore National Liver Transplant Programme since its inception were captured and outcomes were retrieved and described. RESULTS: 562 patients were referred for liver transplant evaluation from 1990-2004, consisting of 457 adults and 105 children. The main indications for referral were hepatitis B liver disease and hepatocellular carcinoma in adults, and biliary atresia in children. Most patients were of United Network of Organ Sharing (UNOS) status 3 or 4 at the time of referral. 114 (20.28 percent) patients had transplants, consisting of 66 adults (14.44 percent) and 48 (45.71 percent) children. 138 adults and ten children were rejected for transplant, mainly for the reason of being "too early". The median waiting time for adults who had transplants was 3.3 months while adults still on the waiting list had been waiting for 16.2 months. The overall waiting list mortality was 44.3 percent, being 52.5 percent in adults and 23.2 percent in children. CONCLUSION: The overall transplantation rate is low and the waiting list mortality is high as a result of low availability of organs, particularly in adults. Paediatric liver transplant appears to have been better at dealing with referred patients but this is probably due to availability of living-related liver transplant. Improvement in these may result from the Human Organ Transplant Act.

Successful listing of patients for liver transplant was related to participation of referring doctor in the transplant program.

INTRODUCTION: Experience with liver transplantation is limited in many parts of Asia. Therefore, patients from nontransplant centers may not be referred in a timely fashion for transplants. Our aim was to evaluate the pattern of referral for liver transplantation and their outcomes in Singapore. METHODS: Consecutive patients referred from 1990 to 2001 were reviewed. Patients from any hospital in Singapore (or the region) could be referred to the program. They were discussed at the weekly meetings. Appropriate patients were placed on the waiting list. "Pending" indicated that the disease was early or there were unsettled medical or social issues. Unsuitable patients were "rejected" for transplant. RESULTS: There were 385 patients referred over a 12-year period. Hepatitis B cirrhosis and hepatocellular carcinoma (HCC) were the most common indications among adults, whereas biliary atresia was the most common for children. Pediatric patients were more likely than adult patients to be listed for transplant (53/76 vs 106/309, P < .001). Patients referred by regular attendees of the program were more likely to be accepted than nonattendees (38% vs 25%, P = .04). "Disease too early", "advanced HCC", and "refusal by family members" were the most common reasons for rejection. CONCLUSION: Members of the Liver Transplant Program were more likely to refer suitable patients for transplant at the appropriate time. Better interaction between gastroenterologists inside and outside the transplant program would help to improve the timing of referrals for liver transplantation, and hence, patient survival.

Basiliximab (Simulect) for the treatment of steroid-resistant rejection in pediatric liver transpland recipients: a preliminary experience.

BACKGROUND: The role of interleukin-2 receptor antibodies as rescue therapy in steroid-resistant rejection (SRR) has not been studied. We evaluated the safety and efficacy of an interleukin-2 receptor antibody, basiliximab (Simulect, Novartis, East Hanover, NJ), in treating SRR in pediatric liver transplant recipients. METHODS: This was a prospective study of seven pediatric liver transplant recipients with biopsy-proven SRR who would have otherwise received OKT3 or antithymocyte globulin. The primary immunosuppression consisted of cyclosporine (Neoral, Novartis), azathioprine, and prednisolone in four patients and tacrolimus and prednisolone in three patients who had undergone retransplantation for chronic rejection (n=2) and hyperacute rejection (n=1). Four patients had received two cycles of high-dose steroids, and three patients had received a single cycle; all had been converted to tacrolimus, followed by the addition of mycophenolate mofetil. RESULTS: The median time from transplant to SRR was 30 days (range, 8 days-23 months). Five children received two doses of basiliximab (10 mg, 3-7 days apart), and two children received a single dose. Aspartate aminotransferase levels normalized in three children 12, 21, and 30 days after basiliximab treatment. Aspartate aminotransferase levels decreased without normalizing in two children, but there was no further evidence of cellular rejection on repeat biopsies. All five children are rejection-free with a median follow-up of 22 months (range, 5-32 months). Biochemical abnormalities persisted in the remaining two children, and both developed chronic rejection. There were no immediate side effects associated with basiliximab. Two patients were treated empirically for possible cytomegalovirus infection 21 and 57 days after basiliximab treatment, with no evidence of cytomegalovirus disease. CONCLUSION: Five of seven pediatric liver transplant recipients with SRR experienced successful outcomes with basiliximab treatment without major side effects, indicating that it is a safe alternative to OKT3 and other antilymphocyte antibodies.

Use of hypoallergenic formula in the prevention of atopic disease among Asian children.

OBJECTIVE: To determine the effect of a partially hydrolysed formula on genetically predisposed children, with respect to the development of atopic clinical manifestations and in vitro testing of serum IgE levels (total and milk-specific). METHODS: One hundred and ten infants were randomly assigned to receive either partially hydrolysed formula or standard infant formula, and were prospectively monitored from birth for clinical atopic symptoms and serum IgE levels. RESULTS: Eczema occurred less frequently in infants receiving partially hydrolysed formula. This was significant (P < 0.05) at 3, 6, 9, 12, 18 and 24 months. However, the significance decreased with time, although it almost reached statistical significance at 30 months by the Kaplan-Meier survival function (log-rank statistic, 3.46; P = 0.063). Although wheezing occurred less frequently in infants receiving partially hydrolysed formula, compared to those receiving standard infant formula, the difference did not reach statistical significance (P > 0.05). CONCLUSIONS: Exclusive feeding of hypoallergenic milk formula in the first 4 months of life has a protective effect in terms of the development of atopic dermatitis in the first 2 years of life, compared to feeding with cow's milk formula.

Calcineurin-inhibitor related nephrotoxicity- reversibility in paediatric liver transplant recipients.

AIM: To study the efficacy of mycophenolate mofetil (MMF) as renal rescue in paediatric liver transplant recipients with calcineurin-inhibitor- (CI) related nephrotoxicity. METHODS: Pediatric liver transplant recipients with stable graft function and a glomerular filtration rate (GFR) <80 ml/min/1.73 m2 were enrolled. MMF was introduced at 20 mg/kg/day and increased to 40 mg/kg/day after 1 week. CI dose was then reduced 6 weeks to achieve blood levels 25% of baseline. GFR was reassessed after 6 and 12 months. RESULTS: Fourteen children with a median (range) interval from transplant of 57 (4-111) months were studied. Their median (range) GFR in ml/min/1.73 m2 increased from a baseline of 52 (31-71), to 69 (38-111) and 73 (35-98) at 6 and 12 months, respectively (P=0.00014). Side effects of MMF include leucopaenia in two and backache in one, two of whom discontinued MMF. Acute allograft rejection occurred in three children. All 14 are well with a median (range) follow-up of 24 (14-38) months from MMF introduction. CONCLUSION: MMF allows the recovery of renal function from CI related nephrotoxicity in more than 70% of paediatric liver transplant recipients with renal impairment.

Liver transplantation in a child with severe hypercholesterolaemia in Alagille syndrome.

INTRODUCTION: Liver transplantation is a curative treatment modality in children with end stage liver disease in Alagille syndrome. CLINICAL PICTURE: We report a 3-year-old child with this condition who had severe hypercholesterolaemia, pruritus and extensive xanthomatosis. TREATMENT: Liver transplantation was performed in this patient. OUTCOME: He recovered well with normalisation of his lipid profile. This procedure also resulted in resolution of the disfiguring xanthomatosis.