Recording Bessel-like beam shapes generated by plasmonics lens

In our study, we spun a negative photoresist layer on top of a plasmonic lens which was formed by adopting a metallic ring structure with a nano-scale width opening. We recorded the beam shape of the Bessel-like beam emitting from the plasmonic lens which formed a high aspect ratio structure. We found that the high aspect ratio structure was higher after exposure as the inner and outer diameter had increased. In addition, we used an oblique incidence on the negative resist metallic ring structure to produce an inclined micro-structure. Different exposure results were obtained with the two different metal thicknesses. Therefore, in our study, we not only proved that it is possible to record the shape of a Bessel-like beam, but we also demonstrated that it is possible to create a plasmonic lens which is capable of creating a high aspect ratio structure through exposure.

The effect of a user-guided request form for chest radiographs in a neonatal intensive care unit

The objectives of this prospective, observational study were to determine the current indications of requesting chest radiograph in sick infants in a neonatal intensive care unit (NICU) and the effect of a user-guided request form for chest radiographs of sick infants. During the three-month study period, a total of 423 chest radiographs were requested on 159 sick newborn infants in the intensive area of this NICU. A majority (55.6%) of these chest radiographs were performed to verify positions tips of either central catheters (27.4%) or endotracheal tubes (28.1%). The number of chest radiographs done during the period when the user-guided request forms were utilised was significantly lower (1.24 per patient) than before (1.37 per patient) or after (1.58 per patients) the period when these forms were in use (p=0.01). The rate of radiological abnormalities detected in radiographs requested to verify position of tips of endotracheal tubes were significantly greater during the period when user-guided forms were used than when they were not (p=0.01). A significantly higher proportion of changes in management were instituted when the user-guided forms were in use than during the period when they were not used (p=0.03). We conclude that a user-guided radiographic request form helps doctors in NICU to carry out their management more effectively.

Left paraduodenal hernia presenting as intestinal obstruction: report of one case

We report a case of internal hernia of the small intestine in a 13-year-old boy with presentation of partial intestinal obstruction. The patient suffered from recurrent abdominal pain and chronic constipation over the past few years. An abdominal mass was suspected from clinical manifestations and images derived from abdominal echography. Upper gastrointestinal contrast study revealed poor motility at the distal jejunum with barium stasis. Follow-up film on the next day delineated medially and downwardly displaced splenic flexure and proximal descending colon. At operation, total herniation of small intestine into a retroperitoneal space through a defect on left mesocolon was noted. A left paraduodenal (mesocolic) hernia was diagnosed. The patient made an uneventful recovery after the hernia was repaired. This report provides unusual image clues of internal hernias of the small intestine presenting as ileus. Though rare, paraduodenal hernia should be taken into account in a differential diagnosis of intestinal obstruction. Early surgical intervention allows uneventful recovery to occur and also prevents the possible complication of gangrenous bowels.

Non-A, non-B, non-C hepatitis: its significance in pediatric patients and the role of GB virus-C

OBJECTIVES

To delineate the importance of non-A, non-B, non-C (non-ABC) hepatitis, and the role of GB virus C (GBV-C) in children.

METHODS

From 1980 to 1995, acute-onset viral hepatitis was diagnosed in 166 inpatients and categorized into type A, B, C, and non-ABC hepatitis according to the serologic markers or the results of polymerase chain reaction assay for HBV DNA or HCV ribonucleic acid (RNA) in the National Taiwan University Hospital. Non-ABC hepatitis was diagnosed in 57 patients (34%). GBV-C RNA was investigated by reverse transcription and nested polymerase chain reaction in 32 of the 57 patients with non-ABC hepatitis. The clinical and laboratory features of patients with acute non-ABC hepatitis were compared with the features of those with acute hepatitis A and B.

RESULTS

The degree of abnormality in aminotransferase activities was milder in patients with non-ABC hepatitis than in those with hepatitis B; chronicity was noted in 12%. Fulminant hepatitis occurred in 16%, and the mortality rate was 56%. Young age carried a significantly higher risk of having a fulminant course (1.9 +/- 0.2 years of age vs 6.4 +/- 5.1 years of age in acute course; p < 0.05). Compared with fulminant hepatitis B, fulminant non-ABC hepatitis had a trend of a longer interval from onset to death (119.2 +/- 144.8 vs 15.2 +/- 8.4 days; p = 0.079). GBV-C RNA was detected in only two of the patients tested, both of whom had received transfusions; one had persistent viremia and fluctuating aminotransferase values.

CONCLUSIONS

Non-ABC hepatitis plays an important role in the etiology of pediatric viral hepatitis; however, the role of GBV-C is minor. A search for other unknown viral agent(s) responsible for non-ABCG hepatitis is needed.

Thenar hypoplasia in Klippel-Feil syndrome due to aberrant radial artery

A 10-year-old boy with Klippel-Feil syndrome had progressive atrophy of the left thenar eminence and absence of left radial pulse. Neurophysiologic studies and angiography were normal. However, duplex sonography over the wrists revealed an aberrant left radial artery. We speculate that the thenar atrophy in this patient is congenital, which may be due to the anomaly of the left radial artery, and is further compromised by vascular compression in the thoracic outlet.

Differential diagnosis of extrahepatic biliary atresia from neonatal hepatitis: a prospective study

The clinical presentations of cholestasis in infancy caused by neonatal hepatitis and biliary atresia are very similar. Diagnosis may be difficult on many occasions, but the surgical treatment of biliary atresia should be performed as early as possible. We established a 3-day workup protocol for the differential diagnosis of biliary atresia and neonatal hepatitis and compared the diagnostic accuracy, sensitivity, specificity, and predictive values of various methods. One hundred and twenty-six infants, including 84 with neonatal hepatitis (age, 65.1 +/- 24.1 days) and 42 with biliary atresia (age, 60.3 +/- 31.1 days), were studied prospectively from July 1982 to December 1990. The diagnostic accuracy of various methods was as follows: liver histology, 96.8%; color of duodenal juice, 91.6%; peak radioisotope count in duodenal juice, 84.2%; ultrasonographic examination of the hepatobiliary system, 80.2%; and persistence of clay-colored stool, 80.2%. After stepwise logistic regression, the diagnostic methods of significance were liver biopsy, color of duodenal juice, abdominal ultrasonography, and stool color. However, stool color and the onset of jaundice could not differentiate severe neonatal hepatitis from biliary atresia. The diagnostic methods of significance then were liver biopsy and duodenal juice color. With this 3-day protocol, no biliary atresia was missed although four cases of neonatal hepatitis were misdiagnosed, resulting in unnecessary laparotomy; we found an overall diagnostic accuracy of 96.8%. We conclude that this 3-day diagnostic protocol is very helpful in the differential diagnosis of neonatal hepatitis and biliary atresia. Liver histologic examination is the most reliable single test for the differential diagnosis.

Antiproliferative effect of esculetin on vascular smooth muscle cells: possible roles of signal transduction pathways

The effect of esculetin, a coumarin derivative with lipoxygenase inhibitor activity, on the proliferation response of cultured rabbit vascular smooth muscle cells was studied. Proliferation response was determined by the uptake of tritiated thymidine. Esculetin (10(-5)-10(-4) M) dose dependently inhibited the enhanced proliferation stimulated by 5% fetal calf serum. The structure-activity relationship of esculetin and eight other coumarin derivatives indicates that two adjacent phenolic hydroxyl groups at the C-6 and C-7 positions in the coumarin skeleton are necessary for the potent antiproliferative effect. The antiproliferative effects of other lipoxygenase inhibitors, 5,8,11,14-eicosatetraynoic acid (ETYA) and ketoconazole, were comparable to the effect of esculetin. However, esculetin exhibited the greatest maximal suppression. The enhanced releases of 12-hydroxyeicosatetraenoic acid (12-HETE), prostaglandin E2 and 6-keto-prostaglandin F1 alpha in the culture medium of smooth muscle cells stimulated by 5% fetal calf serum were significantly reduced by esculetin. Furthermore, the fetal calf serum-stimulated protein tyrosine kinase activity was reduced by esculetin (10(-5)-10(-4) M) in a dose-dependent manner. In contrast, the protein kinase C activity stimulated by phorbol-12-myristate-13-acetate was not affected by esculetin (10(-6)-10(-4) M). These results suggest that the antiproliferative effect of esculetin on vascular smooth muscle cells may be partly mediated through inhibition of protein tyrosine kinase and modulated by inhibition of lipoxygenase.

Cytomegalovirus-associated neonatal hepatitis

Fifty-five patients with cytomegalovirus (CMV)-associated neonatal hepatitis (NH) were followed for 12 to 90 months. Six patients (10.9%) died from either a fulminant course or a chronic liver disease. Among the remaining 49 patients, whose liver function was completely recovered, there were eight with retardation of developmental or growth status, and two with hearing impairment. Overall, 20.4% of the survivors suffered from a long-term impact. The unfavorable outcome was related to several clinical and pathological parameters. These included persistence of clay-colored stool, presence of splenomegaly, ascites or anemia, high peak total and direct bilirubin, low nadir albumin levels, diffuse giant cell transformation and cirrhosis of the liver. The seropositivity of CMV infection did not significantly correlate with the outcome.