Role of a modified ultrafast MRI brain protocol in clinical paediatric neuroimaging.

AIM: To establish a role for modified ultrafast magnetic resonance imaging (MRI) of the brain in clinical paediatric patients based on clinically acceptable image quality and diagnostic accuracy. MATERIALS AND METHODS: A prospective study was conducted with institutional review board approval on an ultrafast MRI brain protocol consisting of sagittal T1-weighted, axial T2-weighted, axial fluid-attenuated inversion recovery (FLAIR), axial diffusion-weighted imaging (DWI), and axial T2∗-weighted sequences. Preliminary investigations revealed that the default ultrafast T2-weighted sequence was prone to pulsation artefacts. A modified ultrafast T2-weighted sequence was therefore developed to replace the default ultrafast T2-weighted sequence. Thirty-five patients with clinical indication for neuroimaging underwent ultrafast MRI, modified ultrafast T2-weighted sequence and standard MRI at 3 T. Image quality of ultrafast MRI sequences were graded as clinically "diagnostic" or "non-diagnostic" and compared against the corresponding standard MRI sequences as the reference standard. The modified ultrafast T2-weighted sequence surpassed the default ultrafast T2-weighted sequence in image quality. The ultrafast MRI protocol was therefore replaced with the modified ultrafast T2-weighted sequence creating a modified ultrafast MRI protocol. The clinical reports of modified ultrafast MRI were compared against standard MRI for diagnostic concordance, categorised further as "normal", "clinically significant", or "clinically minor" abnormalities. RESULTS: Ultrafast T1-weighted, FLAIR, and DWI sequences had comparable image quality to standard MRI sequences. The ultrafast T2∗-weighted sequence had significantly higher non-diagnostic images (42.9%) compared to the standard MRI sequence (2.9%). The default ultrafast T2-weighted sequence had significantly higher non-diagnostic images compared to the modified ultrafast T2-weighted sequence and standard T2-weighted sequence (82.9%, 5.7%, 8.6%, respectively). There was 100% concordance for normal and clinically significant abnormalities and 23% discordance for clinically minor abnormalities. Modified ultrafast MRI takes 5 minutes 41 seconds compared to standard MRI time of 14 minutes 57 seconds. CONCLUSION: The modified ultrafast MRI protocol for brain imaging demonstrates clinically acceptable image quality in four out of five sequences and has high accuracy in diagnosing normal and clinically significant abnormalities when compared against the standard MRI protocol for brain imaging. It could potentially benefit a select group of paediatric patients who require neuroimaging.

The most useful cranial ultrasound predictor of neurodevelopmental outcome at 2 years for preterm infants.

AIM: To determine the most important cranial ultrasound predictors of abnormality associated with neurodevelopmental outcome at 2 years of age in preterm infants. MATERIALS AND METHODS: A total of 343 preterm infants born between 2005 and 2010 and cared for in KK Women's and Children's Hospital, a tertiary paediatric hospital, with birth weight ≤1,250 g were assessed in this retrospective study. Serial cranial ultrasound examinations were examined for intraventricular haemorrhage and cystic periventricular leukomalacia. Ventricular-brain ratio on term equivalent cranial ultrasound was measured. Neurodevelopmental outcome was assessed by the performance on Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley-III) at 2 years corrected age. Mental delay was defined as having a combined Bayley-III score (the average of cognitive and language scores) <80. RESULTS: The mean cognitive, language, and motor scores on Bayley-III in this cohort were 93±15, 83±18, and 92±15, respectively. Twenty-six percent of the preterm infants had mental delay and 4% had cerebral palsy. Ventricular-brain ratio >0.35 was the most significant factor associated with mental delay (odds ratio 5.28, 95% CI: 1.49-18.71, p=0.01). Other significant risk factors for mental delay were male gender, postnatal steroids, and necrotising enterocolitis, whereas maternal tertiary education was a protective factor against adverse outcome. CONCLUSION: Ventricular-brain ratio >0.35 on term-equivalent cranial ultrasound in preterm infants is the strongest predictor for mental delay on Bayley score at 2 years of age.

Using a checklist to assess if a child undergoing MRI needs general anaesthesia.

AIM: To assess if a child-assessment checklist covering tasks children are expected to perform during magnetic resonance imaging (MRI) can determine whether the child requires general anaesthesia (GA) during MRI. MATERIALS AND METHODS: In this institute review board approved study, children who underwent MRI from September 2016 to June 2017 at KK Women's and Children's Hospital were assessed using a checklist by a research assistant before their examination. During this project, the checklist had no influence on whether the MRI was performed under GA or not. The checklist consisted of five items rated on a binary scale assessing the child's behaviour. Binary logistic regression was performed separately on the overall sample and for a subset of younger children to identify variables associated with the requirement for GA. RESULTS: The mean age of the overall sample (798 children) and the subset of children <8 years (124 children) were 11.7±3.7 and 5.5±1.3 years, respectively. In both groups, children who required GA were significantly younger than those who did not (p<0.001). No gender differences were observed. Children who required GA scored higher on the checklist compared to those who did not in both groups (p<0.001). The diagnostic accuracy of the checklist was found to be good (area under the curve [AUC]=0.97 for both groups), with a suggested cut-off score of 4. Intraclass correlation coefficient of the ratings by two independent individuals was 0.78. CONCLUSION: The child assessment checklist was useful in identifying GA requirement in children undergoing MRI and can be administered by non-medical staff with good inter-rater reliability.

Effects of female sex hormones on folic acid-induced anti-angiogenesis.

AIM: Pregnant women have been recommended to take FA daily to prevent birth defects in the brain and spinal cord. We previously showed that folic acid (FA) exerts an anti-angiogenic activity. As angiogenesis is important for endometrial reorganization and embryonic development, there should be some mechanisms to allow the pregnant mother and the foetus to escape from the FA-induced anti-angiogenesis. This study was designed to investigate the effect of female sex hormones on the FA-induced anti-angiogenic activity. METHODS: The protein levels and protein-protein interaction were examined by Western blot analysis and immunoprecipitation assay respectively. The cell proliferation and migration were examined by MTT assay and wound healing assay respectively. The in vivo angiogenesis was evaluated by Matrigel angiogenesis assay. RESULTS: In human umbilical venous endothelial cells (HUVEC), FA receptor (FR) formed a complex with progesterone receptor (PR), oestradiol receptor (ER) and cSrc. Pregnancy levels of progesterone (P4) or oestradiol (E2) prevented FA-induced inhibitions of proliferation and migration in HUVEC. Both E2 and P4 prevented the FA-induced anti-angiogenesis in vivo. Moreover, cotreatment with FA and P4 or E2 inhibited the signalling pathways involved in FA-induced inhibitions of proliferation and migration in HUVEC. CONCLUSION: Female sex hormones interrupt the FA-induced anti-angiogenic action through receptor-receptor interaction.

Review of congenital inner ear abnormalities on CT temporal bone.

The aetiology of profound hearing loss in children is complex and multifactorial. Congenital inner ear abnormality is a major cause of hearing loss in children. CT temporal bone imaging is the modality of choice in the investigation of hearing loss. Recognising the congenital abnormalities of the inner ear guides the clinician's management of the condition. This pictorial essay illustrates the congenital abnormalities of the inner ear on high resolution CT temporal bone images and correlation with developmental arrest during embryology.

Clinics in diagnostic imaging (133). Retained placenta from an intra-abdominal pregnancy.

A 29-year-old Indonesian woman presented with abdominal pain seven months after an intra-abdominal pregnancy. Ultrasonography revealed a cystic mass in the pelvis and magnetic resonance imaging showed an umbilical stump within it, indicating a retained placenta. This was removed surgically, and on histology, an infarcted placenta was confirmed.

Primitive neuroectodermal tumour metastases mimicking neurofibromatosis type 2.

Bilateral vestibular schwannomas are the diagnostic features of neurofibromatosis type 2 (NF-2), and are the most common findings associated with the disorder. We report a three-year-old boy who presented with left facial nerve palsy and weight loss with bilateral large cerebellopontine (CP) angle masses that extended into the internal auditory canal on magnetic resonance imaging. The patient also had synchronous tumours in the lateral ventricle and intradural extramedullary spinal canal. The above findings were misinterpreted as NF-2 with bilateral vestibular schwannomas, ventricular meningioma and spinal schwannomas/meningiomas. However, histological examination of the spinal masses revealed a primitive neuroectodermal tumour. Although bilateral CP angle masses are characteristic of NF-2, the possibility of diffuse craniospinal malignancy should be considered in a very young child who presents with weight loss and extensive tumours.

Primary neuroblastoma of the mandible.

Primary neuroblastoma of the mandible is rare with only seven cases reported to date. The diagnosis is made after any possible primary tumour has been adequately investigated for and excluded. We report a one-year nine-month-old girl with a primary neuroblastoma of the mandible and discuss its possible aetiology.

Agenesis of the corpus callosum: an MR imaging analysis of associated abnormalities in the fetus.

BACKGROUND AND PURPOSE: Anomalies associated with callosal agenesis (ACC) found postnatally have been well documented. However, to our knowledge, no detailed MR imaging analysis of associated anomalies has been reported in a large cohort of fetuses with ACC. This study will assess those anomalies and compare them with postnatal cohorts of ACC, to identify associated fetal brain abnormalities that may give insight into etiology and outcome. MATERIALS AND METHODS: All cases of ACC diagnosed on fetal MR imaging during an 11-year period were retrospectively reviewed, including fetal MR imaging, postnatal MR imaging, and autopsy findings. Neurodevelopmental outcome was classified as poor in children with seizures and/or severe neurodevelopmental impairment or in cases of neonatal death. RESULTS: Twenty-nine cases of ACC were identified. Median gestational age was 26.14 weeks (range, 19.71-36.43 weeks). Twenty-three fetuses had delayed sulcation and/or too-numerous cortical infoldings (abnormal morphology). Fifteen fetuses had cerebellar and/or brain stem abnormalities. Fetal MR imaging findings suggested a genetic syndrome in 5 fetuses and an acquired etiology or genetic/metabolic disorder in 2 fetuses. Findings were confirmed in 8 cases with postnatal MR imaging, except for delayed sulcation and small vermis, and in 4 cases with autopsy, except for periventricular nodular heterotopia and abnormalities in areas not examined by autopsy. Neurodevelopmental outcome was good in 7 and poor in 9 children. Abnormal sulcal morphology and/or infratentorial abnormalities were present in those with poor outcome and absent in those with good outcome. CONCLUSIONS: ACC is infrequently isolated in fetuses. Abnormal sulcation is common and suggests more diffuse white matter dysgenesis in these fetuses.

Indiscernible benefit of high-resolution HLA typing in improving long-term clinical outcome of unrelated umbilical cord blood transplant.

The success of allogeneic hematopoietic stem cell transplantation depends in part on the accuracy of human leukocyte antigen (HLA) matching between the donor-recipient pair. The higher the number of matching HLA alleles, the smaller the chance that the transplant recipient will develop complications. Umbilical cord blood (UCB) transplantation was noted to result in a remarkably low frequency and severity of graft-versus-host disease (GvHD) and graft rejection compared to that in unrelated bone marrow transplant recipients. At present most banks match UCB donors for respective recipients by HLA-A, -B low-resolution typing and -DRB1 high-resolution typing. We retrospectively conducted high-resolution sequence-based HLA typing on DNA samples available from 65 Chinese UCB-recipient pairs typed previously by using low-resolution sequence-specific oligonucleotide probes and sequence-specific primers, and evaluated the clinical outcome. High-resolution typing revealed imperceptible HLA alleles that were hardly identified in low-resolution typing. Univariate analyses demonstrated no significant correlation between the extents of high-resolution HLA disparity with engraftment, graft failure, acute GvHD, transplant-related mortality and long-term 6-year overall survival. Data from the study suggest that high-resolution typing for HLA-A, -B and -DRB1 contributed no substantial improvement to UCB transplant outcome. Low-resolution typing appears to be amenable to matching UCB-recipient pairs without compromising the quality of transplant.

Hysterosalpingography: current applications.

With the recent advances in reproductive medicine, hysterosalpingography has become a relatively quick and noninvasive examination to evaluate fallopian tubes and uterine cavity. It remains the best modality to image fallopian tubes. Congenital uterine malformations, technical artefacts and pathological findings are depicted. Pathological findings that can be detected on hysterosalpingography include salpingitis isthmica nodosa, tubal blockage, peritubal adhesion, submucosal leiomyoma, endometrial polyp, endometrial carcinoma, synechiae and adenomyosis.

Banking and transplantation of umbilical cord blood in Guangzhou, China.

BACKGROUND: Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells (HSC) for transplantation of patients with hematologic malignancies or hereditary diseases. METHODS: We developed a provincial UCB bank in Guangzhou, China, using good manufacturing practices and standard operating procedures to address donor eligibility, collection, characterization, processing, storage and release from quarantine. The banking activities were analyzed. RESULTS: From June 1998 to May 2005, 8623 UCB units of Han ethnic origin were collected; 4147 (48.1%) were stored, while 4476 (51.9%) were discarded as a result of pre-determined exclusion criteria. A median volume of 95.5 mL (range 60-227.7) and 1.2 x 10(9) (0.8-9.3) nucleated cells were collected. The cell viability was 97.8% (90-100%). The CD34+ cell count of 3691 (89.0%) UCB units was 5.2 x 10(6) (0.3-131.6) and clonogenic assays of 4036 (97.3%) UCB units demonstrated 9.8 x 10(5) (0.04-135.8) CFU-GM, 0.3 x 10(5) (0.0-18.6) CFU-GEMM and 8.8 x 10(5) (0.0-74.2) BFU-E. A total of 0.4% (15/3863) UCB derived from babies known to have health problems at age 6 months was discarded. Up to May 2005, 151 units were issued for transplantation to 127 patients [90 (70.9%) children and 37 (29.1%) adults]. The infused nucleated cells in unrelated single-unit recipients were 3.4 x 10(7)/kg (1.7-14.9) for adults (n=19) and 5.7 x 10(7)/kg (2.0-20.5) for children (n=71), respectively. The numbers of days for the engraftment of neutrophils among 65 children and 22 adults were 17 (7-41) and 20 (10-42), respectively. DISCUSSION: Data of this study show that stringent procedures and comprehensive policies are requisite for pursuing the banking and release of quality UCB for successful transplantation.

HPLC analysis of reduced and oxidized coenzyme Q(10) in human plasma.

BACKGROUND: The percentage of reduced coenzyme Q(10) (CoQ(10)H(2)) in total coenzyme Q(10) (TQ(10)) is decreased in plasma of patients with prematurity, hyperlipidemia, and liver disease. CoQ(10)H(2) is, however, easily oxidized and difficult to measure, and therefore reliable quantification of plasma CoQ(10)H(2) is of clinical importance. METHODS: Venous blood was collected into evacuated tubes containing heparin, which were immediately placed on ice and promptly centrifuged at 4 degrees C. The plasma was harvested and stored in screw-top polypropylene tubes at -80 degrees C until analysis. After extraction with 1-propanol and centrifugation, the supernatant was injected directly into an HPLC system with coulometric detection. RESULTS: The in-line reduction procedure permitted transformation of CoQ(10) into CoQ(10)H(2) and avoided artifactual oxidation of CoQ(10)H(2). The electrochemical reduction yielded 99% CoQ(10)H(2). Only 100 microL of plasma was required to simultaneously measure CoQ(10)H(2) and CoQ(10) over an analytical range of 10 microg/L to 4 mg/L. Intra- and interassay CVs for CoQ(10) in human plasma were 1.2-4.9% across this range. Analytical recoveries were 95.8-101.0%. The percentage of CoQ(10)H(2) in TQ(10) was approximately 96% in apparently healthy individuals. The method allowed analysis of up to 40 samples within an 8-h period. CONCLUSIONS: This optimized method for CoQ(10)H(2) analysis provides rapid and precise results with the potential for high throughput. This method is specific and sufficiently sensitive for use in both clinical and research laboratories.

Protective effect of human CD40-Ig fusion protein in a murine model of acute graft-versus-host disease.

OBJECTIVE: To investigate the protective effects of blocking CD40/CD40L interactions with human CD40-Ig fusion protein in a murine graft-versus-host disease model. METHODS: Human CD40 gene extracellular region was inserted into plasmid pIG1, which contains genomic human IgG1 Fc gene. A transient vector containing CD40-Fc fusion gene was transfected into COS-7 cells. The CD40-Ig fusion protein was detected through enzyme-linked immunosorbent assay (ELISA). A constitutive vector was also generated by ligating the CD40-Fc fusion gene into pcDNA3.1 and transfecting it into CHO cells. CD40-Ig was purified by protein A affinity chromatography. SDS-PAGE, Western blot and ligand binding assay were used to identify the qualities of CD40-Ig. Murine acute graft-versus-host disease (GVHD) was induced by intravenous injection of C57BL/6J (H-2b) spleen cells into sub-lethally irradiated BALB/c (H-2d) mice. Protective effects against murine graft-versus-host disease by in vivo administration of CD40-Ig were evaluated. RESULTS: Mammalian expression vectors pIG/40Ig and p3.1/40Ig were constructed as described above. Chimeric proteins were expressed in COS-7 and CHO cell culture supernatant and confirmed by ELISA and Western blot. SDS-PAGE showed that fusion proteins had a disulfide-bonded dimeric structure and existed as homodimer. Purified CD40-Ig could bind to CD40L. In vivo administration of CD40-Ig could prevent the development of GVHD and significantly prolong the mean survival time of mice with graft-versus-host disease. CONCLUSIONS: These results demonstrate that CD40/CD40L interactions play an important role in the pathogenesis of graft-versus-host disease and suggest clinical potential for CD40-Ig in the prevention and treatment of human graft-versus-host disease.

Biological features of mesenchymal stem cells from human bone marrow.

OBJECTIVE: To study the biological characteristics of mesenchymal stem cells (MSCs) from human bone marrow. METHODS: A culture of mesenchymal stem cells was initiated from bone marrow low-density mononuclear cells separated by Percoll Centrifugation and maintained in low-glucose Dulbecco's modified Eagle's medium (DMEM) with 10% selected fetal calf serum. Cell growth pattern and its responses to cytokines were evaluated by trypan blue exclusion and MTT test, respectively. Cell cycle and surface antigenic features were analyzed by flow cytometry technique. Cytochemistry characteristics of MSCs were determined. RESULTS: Easy-handling methods to isolate and culture expand MSCs were developed in this study. MSCs were unique in their phenotypes. They were positive for CD29, CD44, CD166, and negative for CD34, CD45, HLA-DR and Ulex europaeus. Cytochemistry evaluation showed that MSCs were homogeneously positive for acid alpha-naphthl acetate esterase (ANAE), glycogen (periodic acid Schiff reaction, PAS), and negative for acid phosphatase (ACP) and the Sudan black reaction (SB). Around 5% of them were positive for alkaline phosphatase (ALP). The cells had a population doubling time of 30 hours and cell cycle analysis showed that approximately 10% of them were in S phase. MSCs grew at significantly different rates when incubated in the presence of various recombinant human cytokines, of which interferon gamma, tumor necrosis factor alpha, stem cell factor and insulin-like growth factor promoted the proliferation of MSCs dramatically, while others tested had no effects on cell growth. CONCLUSIONS: MSCs are a homogenous population of cells that have unique growth, phenotypical and cytochemical characteristics. Furthermore, the diverse responses of MSCs to different cytokines provide a clue for the selection of optimal expansion and maintenance of MSCs.

[The transfection and expression of retro viral-mediated human FL cDNA in bone marrow stromal cell line].

AIM: The expression of retroviral-mediated FL gene transfer into bone marrow stromal cell line HFCL was studied. METHODS: FLT3 ligand (FL) cDNA was recombined with retroviral vector pLXSN by gene recombination technology. The recombinant plasmid was transferred into retrovirus packaging cell line PA3 17 by lipofectamine, and the resistant clones were selected by G418 selective medium. The mRNA expression in HFCL cells and integration of genome DNA were assayed by RT-PCR and genomic DNA PCR. The biological activity of FL in the culture was investigated by mouse bone marrow CFU-GM assay. RESULTS: The recombinant plasmid pLFSN was successfully constructed. The expression of FL mRNA was detected in HFCL cells. In the genome of these infected target cells, neo gene and FL cDNA were successfully expressed. The biological activity of FL in the culture demonstrated that HFCL cells transfected with FL could significantly augment FL in vitro. CONCLUSION: These results suggest that bone marrow stromal cell lines might become target cells of gene therapy.

A community study of male androgenetic alopecia in Bishan, Singapore.

BACKGROUND: Androgenetic alopecia is the most common form of hair loss. It affects a large number of the local male population, with 1,812 men seeking treatment for hair loss at the sole dermatological tertiary referral centre in Singapore in 1994. The aim of this study was to assess the prevalence of male androgenetic alopecia in the community. METHODS: A questionnaire-based cross-sectional survey with a one-stage sampling method was conducted. Each male was diagnosed clinically and the severity graded according to the Norwood Criteria. The survey area was in Bishan East, a housing estate with 8,004 households. A total of 335 households were selected for the survey. RESULTS: The household response rate was 84%. Within these households, 254 out of 378 men participated in the study (67% response rate). The prevalence of androgenetic alopecia was found to be 63%. The prevalence of the condition increased with age, from 32% among young adults aged 17 to 26 years to 100% among those in their 80s. Proportionately more Indians (87%) were affected compared to Chinese (61%). 81% of the respondents with androgenetic alopecia did not seek help as they did not view it as a problem. Of those seeking treatment, 74% used non-medical methods of unproven effectiveness. CONCLUSION: There is a high prevalence of androgenetic alopecia in the community in Singapore. Age specific prevalence and racial differences correlate well with both Western and local studies respectively.

An improved gas chromatography assay for topiramate monitoring in pediatric patients.

An improved micromethod involving capillary gas chromatographic assay with liquid-liquid extraction and nitrogen phosphorus detection (GC/NPD) was developed and validated for the determination of topiramate (TPM) in human body fluids. The galactopyranose analog of TPM was used as the internal standard. Capillary gas chromatographic conditions yielded typical retention times of 6.8 min for TPM and 7.2 min for the internal standard. Calibrations were linear between 1.0 and 32 microg/mL. Between-day precision (n = 17) for three serum controls (3.0, 10, and 24.5 microg/mL) resulted in coefficients of variation of 6.9%, 7.3%, and 4.9%, respectively. The limit of detection was 0.42 microg/mL. There was an excellent linear correlation between the fluorescence-polarization immunoassay (FPIA) and GC/NPD determinations of 56 patient specimens (r2 = 0.981). Chromatograms showed no interfering peaks with the respective blank human samples or from many commonly prescribed drugs. Because of improved specificity and decreased sample volume requirements, this micromethod should be particularly useful for monitoring TPM therapy in pediatric patients, for patients with impaired renal function, and for research studies.