Crystal structures of chitin binding domains of chitinase from Thermococcus kodakarensis KOD1.

Chitinase from T. kodakarensis (TkChiA) catalyzes the hydrolysis of chitin. The enzyme consists of two catalytic and three binding domains (ChBD1, ChBD2 and ChBD3). ChBD2 and ChBD3 can bind to not only chitin but also cellulose. In both domains, the intervals of the side chains of the three tryptophan residues, which are located on the molecular surface, correspond to twice the length of the lattice of the chitin. A binding model with crystalline chitin implies that the tryptophan residues and a glutamate residue interact with the hexose ring by CH-π interactions and the amide group by a hydrogen bond, respectively.

X-ray diagnosis with a bloating agent for foreign object ingestion.

The location of an ingested foreign object is often difficult to determine by X-ray if gastric air bubbles are not clear in the image. Methods that provide negative contrast can facilitate precise object localization, which is important for object retrieval and treatment of the patient. This case report describes a male child, 2 years and 2 mo of age, who accidentally swallowed a lithium battery while playing at home. A plain X-ray showed that the battery was in the abdomen, but it was unclear whether the object was still inside the stomach. A second X-ray examination performed after oral administration of a bloating agent to produce expansion of the stomach and provide negative contrast confirmed that the ingested battery was still in the stomach. The battery was then carefully removed using magnetic and balloon catheters under fluoroscopic guidance. This case report describes the successful use of an orally administered bloating agent without pain to the child in order to determine the precise location of a foreign object in the abdomen.

Children undergoing liver transplantation for treatment of inherited metabolic diseases are prone to higher oxidative stress, complement activity and transforming growth factor-ß1.

BACKGROUND: Main indications for liver transplantation in the pediatric population include biliary atresia and inherited metabolic diseases. The present study evaluated whether there are differences between pediatric patients undergoing living-related liver transplantation due to the two diseases in terms of their oxidative and immunological status during their regular outpatient follow-up visits. MATERIAL AND METHODS: A clinical outpatient study measuring serum oxidative stress index (calculated as serum oxidant/antioxidant ratio, in the form of serum total hydroperoxide/serum biological antioxidative potential), serum terminal complement component 5a, as an indicator of complement activity and immunological status, and transforming growth factor-ß1, as a marker of liver fibrosis, in 16 patients (6 males and 10 females, 2.5-15 years old) who received living-related liver transplantation due to inherited metabolic diseases (n=6; in the form of propionic acidemia [n=1], methylmalonic acidemia [n=1], arginase deficiency [n=1], tyrosinemia [n=2], and glycogen storage disease type 1b [n=1], with an age range of 2.4-14.6 years old) and due to biliary atresia ([n=10], with an age range of 2.9-14.5 years old). RESULTS: Serum oxidative stress index, complement component-5a, and transforming growth factor-ß1 were significantly higher in the inherited metabolic diseases group than in the biliary atresia group. In all patients, serum oxidative stress index correlated positively with complement component-5a and transforming growth factor-ß1. CONCLUSIONS: Patients who receive living-related liver transplantation due to inherited metabolic diseases are prone to higher oxidative stress, complement activity, and serum transforming growth factor-ß1.

Biliary atresia type I cyst and choledochal cyst [corrected]: can we differentiate or not?

BACKGROUND/PURPOSE: It is difficult to discriminate between choledochal cyst[corrected]with obstructive jaundice and biliary atresia with a cyst at the porta hepatis in neonates or young infants. This review evaluates whether it is possible to differentiate between these two diseases. We here also provide an overview of our experience with type I cyst biliary atresia patients. METHODS: Among all the biliary atresia infants who we treated, the infants who were diagnosed with type I cyst biliary atresia were identified and reviewed for their management and outcome. The clinical course and management in different reports were reviewed and compared to the cases presented to our institution. RESULTS: Among the 220 biliary atresia cases, 11 (5 %; male/female: 4/7) were diagnosed to be type I cyst biliary atresia. Two received hepaticoenterostomy and nine received hepatic portoenteros. Three patients had severe late complications; overall, nine (81.8 %) were alive with their native liver and without jaundice. CONCLUSIONS: Patient with choledochal cyst [corrected] are likely to represent larger cysts and inversely, smaller, static, anechoic cysts are more likely to represent cystic biliary atresia. However, exceptional cases were yet presented, and a definitive diagnosis may not be reached. Thus a complete differentiation between choledochal cyst [corrected] from type I cyst biliary atresia is yet hard to reach.

Oxidative stress after living related liver transplantation subsides with time in pediatric patients.

BACKGROUND: Oxidative stress has been suspected to influence graft survival and prognosis in pediatric recipients of living related liver transplantation (LRLT). PURPOSE: We determined the oxidative status of pediatric LRLT recipients during their regular outpatient follow-up visits, and looked for a relationship between oxidative status and post-liver transplantation (post-LTx) duration. PATIENTS: The study included 43 patients (20 males and 23 females) between the ages of 1.6 and 25.1 years (median 10.7 years) who had undergone LRLT from 5 months to 17.5 years (median 7 years) prior to the study, between the ages of 1.2 and 14.4 years (median 3.5 years). METHODS: Serum glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), gamma-glutamyl transpeptidase (γ-GTP), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), direct bilirubin and choline-esterase were measured as part of the patients' regular follow-up visits. Serum total hydroperoxide (TH) and biological antioxidative potential (BAP) were measured using the free radical analytic system which requires 20 µl of serum and 10 min of processing time for each sample. Oxidative stress index (OSI) was calculated as the ratio of TH to BAP. RESULTS: Serum OSI correlated positively with serum levels of GOT, GPT, LDH, ALP, γ-GTP and direct bilirubin. Serum OSI, TH, LDH, ALP and GOT correlated negatively with post-LTx duration. Serum BAP correlated positively with post-LTx duration. Serum TH correlated positively with serum GOT and γ-GTP, but negatively with serum BAP. CONCLUSIONS: (1) The OSI, which can be calculated based on data acquired through a simple outpatient procedure, can serve as an index of our patients' laboratory results and oxidative status. (2) The LRLT recipients in our study were at risk for oxidative stress early in the post-operative period, but this risk subsided with time.

Pediatric patients receiving ABO-incompatible living related liver transplantation exhibit higher serum transforming growth factor-ß1, interferon-γ and interleukin-2 levels.

BACKGROUND: ABO-incompatible liver transplantation (LTx) is becoming more common in response to the paucity of liver allografts. Several studies have expressed concern about the effect of ABO compatibility on graft survival. PURPOSE: To evaluate the differences in serum cytokine levels between ABO-incompatible (ABO-i) and ABO-compatible (ABO-c; includes ABO-compatible and identical) pediatric LTx recipients during regular outpatient follow-up. Note that, in the field of organ transplantation, transplants are categorized as incompatible, compatible or identical; accordingly, these are the terms we use in the paper. MATERIALS AND METHODS: A clinical outpatient study measuring serum transforming growth factor (TGF)-ß1, interferon (IFN)-γ, interleukin (IL)-2 and IL-10 in 43 living related liver transplantation (LRLT) recipients, of whom 36 received ABO-c LRLT (34 were ABO-identical and 2 were non-identical) and 7 ABO-i LRLT. Serum glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, gamma-glutamyl transpeptidase, alkaline phosphatase, lactate dehydrogenase and bilirubin were measured as part of the patients' regular follow-up visits. RESULTS: There were no differences between the ABO-c and ABO-i groups in terms of recipient's age [mean 12.6 vs. 11.1 years (y)], post-LTx duration (mean 7.3 vs. 7.3 y), donor's age (mean 35.5 vs. 34.6 y), body weight (28.9 ± 2.9 vs. 27.9 ± 6.9 kg), or gender (19 female and 17 male vs. 4 female and 3 male). Serum TGF-ß1, IFN-γ and IL-2 were significantly higher in the ABO-i group than in the ABO-c group. IL-10, however, did not differ between the two groups. There was a tendency toward higher γGTP levels in the ABO-i group, but this difference did not reach significance. CONCLUSION: ABO-incompatible LRLTx patients have higher serum TGF-ß1, IFN-γ and IL-2 levels as measured at regular outpatient visits. As a result, they face a higher risk of T-helper 1 cell polarization, which could make graft rejection more likely.

1,25-dihydroxyvitamin D-mediated hypercalcemia in ovarian dysgerminoma.

Humoral hypercalcemia of malignancy (HHM) is a rare complication of malignant pediatric tumors, specifically those that secrete humoral factor(s), such as parathyroid hormone-related peptide (PTHrP). The authors report a case of severe hypercalcemia associated with ovarian dysgerminoma in a 10-year-old girl. In this case, the humoral factor was considered to be 1,25-dihydroxyvitamin D. HHM is extremely resistant to medical therapy. Therefore, tumor resection or volume reduction is necessary to control serum calcium levels.

Results of biofeedback therapy for fecal incontinence in children with encopresis and following surgery for anorectal malformations.

INTRODUCTION: Some children with fecal incontinence respond to biofeedback therapy. However, whether they can achieve fecal continence posttherapeutically has not been clarified. We studied the serial results of biofeedback therapy and discuss the necessity of providing repeated biofeedback therapy at home. METHODS: Nineteen children with encopresis underwent one session of biofeedback therapy. Seven of 15 children with fecal incontinence that developed after surgery for anorectal malformations underwent three to eight sessions of biofeedback therapy; the remaining 8 underwent one (mean, 2.9) session only. The patients were hospitalized for one session of biofeedback therapy. To monitor the clinical outcome of intervention, we used serial score assessments from three months to two years posttherapeutically. RESULTS: Seventeen of 19 (90 percent) patients with encopresis showed clinical improvement after one session of therapy (P < 0.0001). Six months after treatment, however, six of ten (60 percent) patients with encopresis reported recurrent fecal incontinence after one therapeutic session. Clinical improvement was noted in 5 of 15 (33 percent) patients who had fecal incontinence after surgery for anorectal malformations. All five patients showed clinical improvement from six months to two years after several sessions of biofeedback therapy (P < 0.05). CONCLUSIONS: Biofeedback therapy is effective in most children with encopresis and in some children with anorectal malformations. However, some patients need repeated sessions of biofeedback therapy to achieve fecal continence. Therefore, a new portable biofeedback apparatus for the treatment of fecal incontinence at home may be helpful.