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.

Rapid growth of Lymnaea viridis, the intermediate host of Fasciola hepatica, under laboratory conditions

Reported in this communication is a unusually rapid growth of Lymnaea viridis, the intermediate host of Fasciola hepatica, maintained in the laboratory for experimental purposes. When the snails were fed on blue-green algae at about 20 degrees C, they attained a shell length of 12 mm in 37 days from the date of hatching. The snails began laying eggs from 18 to 24 days following hatching.

Characteristics of the Hopfield associative memory utilizing isomorphism relations

Isomorphism relations are utilized to analyze the Hopfield associative memory. When the number of fundamental memories m=/<3, it is proved that two Hopfield associative memories are isomorphic if they have the same mutual distances between the fundamental memories. The number of stable states and the synchronous convergence time of a Hopfield associative memory are shown to be less than or equal to 2 to the power 2(m-1) and 4 to the power 2(m-1), respectively, where m>/=1.

Protection against oxygen toxicity by tracheal insufflation of endotoxin: role of Mn SOD and alveolar macrophages

Endotoxin and the cytokines, tumor necrosis factor and interleukin-1, are known to protect adult rats against O2 toxicity. However, whether the effect of endotoxin is mediated through its direct effect on lung cells or through cytokines is not clear. In this study, we demonstrated that endotoxin at a dosage of 5 micrograms/rat (14-20 micrograms/kg) attenuated O2-induced pulmonary injury and markedly prolonged the survival of rats exposed to 100% O2. Endotoxin was more protective when given by intratracheal insufflation or intravenous injection than by intraperitoneal injection. The endotoxin-induced O2 tolerance was associated with a selective enhancement of pulmonary manganese superoxide dismutase, but not Cu,Zn SOD, mRNA. In addition, depletion of 84% rat alveolar macrophages by liposome-encapsulated dichloromethylene diphosphonate, resulted in a marked reduction (86%) of endotoxin-induced release of tumor necrosis factor into the alveolar space. However, endotoxin was still protective in these alveolar macrophage-depleted animals.

Acute hemiplegia in infancy and childhood

From 1982 to 1991, there were 57 patients diagnosed with various intracranial disorders manifested initially with acute hemiplegia at the Department of Pediatrics, National Taiwan University Hospital. There were 33 boys and 24 girls, aged 12 days to 18 years old. In etiological consideration, cerebrovascular disease (66.7%), intracranial tumors (12.3%) and head trauma (10.5%) accounted for most of the cases. Besides acute hemiplegia, cranial nerve palsy (47.4%), disturbed consciousness (42.1%), headache (42.1%), vomiting (31.6%), focal seizure (21.1%) and fever (21.1%) were also common manifestations. Neuroimage studies of CT/MRI scan and angiography were the most useful diagnostic tools. Treatment modalities included medical treatment in 25 patients and surgical intervention in 16 patients and supportive treatment in the others. There were 12 fatal cases, half of whom died directly of intracranial pathology. The survivors exhibited various neurological deficits, in which motor deficits, mental retardation, and subsequent seizures were the three most common sequelae.

Studies of a sperm/placenta cross-reacting antigen, STX-10

A monoclonal antibody, HSA-10 initially produced against acrosome-reacted human sperm was also shown to cross-react with human placenta/trophoblast. Transmission electron microscopy, as well as indirect immunofluorescent assay, demonstrated that HSA-10 was found to react with antigen on the inner acrosome of human sperm. The cognate antigen, designated as STX-10, was found to exist as an aggregate in the native form when analyzed by Sephacryl S-300 gel filtration chromatography. When purified by HSA-10-immunoaffinity chromatography from human placenta extract, STX-10 was found to be predominantly a group of glycoproteins with a subunit molecular mass in the range of 75 +/- 5 kDa, whereas an additional group of three proteins with subunit molecular mass less than 20 kDa were copurified from human sperm extract. A sandwich enzyme immunoassay was designed to quantitatively determine the immunoactivity of STX-10 in solution, using HSA-10 monoclonal antibody for coating and for signal detection via enzyme conjugation. Based on this assay, it was found that STX-10 could be detected only in human sperm and placenta extract, but not in any other human somatic tissues, such as serum, brain, heart, muscle, kidney and liver. The immunoactivity of STX-10 was found to be sensitive to proteolytic digestion, low pH, in the presence of reducing agent, but resistant to treatment with sodium periodate. This observation suggests that HSA-10 specific epitope is a peptide in nature and not a carbohydrate moiety. Results of antifertility studies revealed that HSA-10 significantly inhibited human sperm penetration to zona-free hamster ova. Thus, the results of this study are consistent with those of WHO Workshop evaluations that seem to suggest that STX-10 is a highly gamete-specific antigen localized on the inner acrosome of human sperm and in human trophoblast/placenta. Therefore, it may play an important role during human fertilization and embryo development.

Postnatal growth of low birthweight neonates in Taiwan

The postnatal growth pattern of four hundred and twenty five Chinese low birth-weight neonates was assessed. All those whose birthweight were below 2500 grams and survived for more than 180 days during the study period were included. The gestational age was between 26 and 40 weeks, and the birthweights were between 766 and 2496 grams, respectively. Infants were grouped according to 250-gram birth-weight categories. The mean age of the lowest weight, mean age of weight regain, and percentage of weight loss were calculated for each weight group and demonstrated an inverse correlation to the birthweight. The mean age of the lowest weight ranged between 2.72 and 6.62 days, mean weight loss was between 4.06 and 14.56%, and age of weight regain was between 4.93 and 17.15 days, respectively.

Multicystic encephalomalacia in a surviving monochorionic twin

From a recent monochorionic diamniotic twin pregnancy seen at this hospital, one of the twins died in utero at 37 weeks' gestation. The other twin, a male infant, was delivered by Cesarean section because of fetal distress, with resuscitation performed in the delivery room. The infant developed generalized tonic seizure shortly after stabilization, and was put on anticonvulsants. The initial brain echography was normal; follow-up echograms and CT scans performed at 8 and 12 days old, respectively, revealed diffuse low density over both side of cerebral hemisphere. At one month old, the infants's brain echogram showed diffuse cystic encephalomalacia. At four months, he was noted to be spastic and significantly delayed in neurodevelopment. Disseminated intravascular coagulation caused by fetal-to-fetal transfer of thromboplastic material from the dead fetus was considered as the most possible cause of the neurological complication in this patient. In addition, perinatal hypoxic-ischemic insult may also have been a superimposed, influencing factor.

Association of HLA-DR14-DR52 with low responsiveness to hepatitis B vaccine in Chinese residents in Taiwan

To determine the HLA-linked immune response gene that controls low responsiveness to hepatitis B surface antigen (HBsAg), HLA typing was performed in 33 initial non-responders (male:female = 23:10, age 1.5-46 years) who had poor antibody response (anti-HBs < 10 mIU ml-1) after four doses of plasma-derived hepatitis B vaccine. Of 33 initial non-responders, 26 received two additional doses of either the same vaccine (n = 18) or recombinant hepatitis B vaccine (n = 8) and returned for anti-HBs measurement. At 1 month after the sixth dose, anti-HBs was still < 10 mIU ml-1 in 20 cases and 10-20 mIU ml-1 in three cases. Analysis of HLA antigen frequencies in these 23 ultimate low responders revealed that nine (39%) were positive for DR14, a statistically significant association of low responsiveness to hepatitis B vaccine with HLA-DR14. In addition, 26% of the ultimate low-responders were positive for DQ3, a frequency significantly lower than the expected rate in the general population. Among the nine ultimate low-responders with DR14, seven were heterozygous for this allele, while the other two cases had a single isolated DR14; and all nine were in association with DR52. These results suggest that a DR14-DR52 association, probably dominantly expressed, may be involved in the low immune responsiveness to hepatitis B vaccine of the Chinese population in Taiwan.

Bench-scale production of acrylamide using the resting cells of Brevibacterium sp. CH2 in a fed-batch reactor

Effects of various organic acids and salts on the stabilization of nitrile hydratase were investigated. The stability of the nitrile hydratase of Brevibacterium CH2 during storage was greatly enhanced by the addition of n-butyric acid. Effects of temperature, pH, and concentrations of acrylonitrile and n-butyric acid on acrylamide production by the resting cells were also investigated. Acrylamide production per unit dry weight of the cells increased 1.33 times by the addition of 0.05% n-butyric acid. A 20% acrylamide solution was successfully produced in a bench-scale reactor (12 l) with only a trace amount of salts after 10 h of hydration reaction under optimum reaction conditions without using an isotonic substrate. The conversion yield was nearly 100%, and acrylic acid as a by-product was not produced. Final acrylamide production of 400 g g-1 cells and productivity of 20 g/(g cells l-1 x h-1) were obtained.

Histologic and ultrastructural features of experimental duodenal ulcers in Sprague-Dawley rats

The histologic and ultrastructural features of a time sequence study of the development, evolution, and healing of acetic acid-induced experimental duodenal ulcer are presented. Duodenal ulcers produced by serosal application of acetic acid featured microvascular injury with progressive disintegration of the tips of the mucosal villi and subtotal necrosis of the duodenal wall. At 3 days ulcers transformed into a chronic state with regenerating epithelium originating from the crypts of the intact bordering mucosa extending toward the center of the ulcers. By 21 days healed ulcers were covered by distorted duodenal surface mucosa. We conclude that this reproducible and standardized model of duodenal ulcer features vascular injury as the earliest microscopic event, that ischemic necrosis leads to ulceration, and that the chronic phase bears morphologic resemblance to human duodenal ulcer.

Insulin and intestinal epithelial cell proliferation

The effects of modification of the levels of endogenous plasma insulin on intestinal epithelial cell proliferation were investigated in rats maintained by total parenteral nutrition (TPN) using either a TPN diet that was high in glucose, or a low glucose (hypocaloric) TPN diet and in orally fed rats (normal and sham operated). The rats were put on their respective treatments for 7 days and were then injected with vincristine sulphate to arrest cells as they entered metaphase. Intestinal tissue was fixed for the determination of crypt cell production rate (CCPR) and blood plasma was taken for hormone radioimmunoassay. Sham operation had no effect on either plasma hormone levels or on CCPR. The standard TPN diet was associated with significantly reduced levels of gastrin, peptide YY and enteroglucagon. Gastrin and PYY were further reduced by the hypocaloric diet. However, plasma insulin was much increased in the TPN but not in the hypocaloric group. Small intestinal CCPR was reduced in the TPN groups, but no difference was observed between the standard and the low calorie TPN diets. The lack of difference in CCPR between the two TPN diets despite the massive elevation of plasma insulin strongly suggests that insulin does not have a substantial role in the control of gastrointestinal epithelial cell renewal.

Persistent pulmonary hypertension of the newborn associated with excessive pulmonary arterial muscularization: report of an autopsy case

A 3700-g male infant born at 37 weeks' gestation presented with cyanosis at birth. He was diagnosed as having persistent pulmonary hypertension of the newborn (PPHN) on the basis of persistent hypoxemia, despite continuous mechanical ventilatory support with 100% O2, and right-to-left shunting through the foramen ovale shown by Doppler echocardiography. Treatment with hyperventilation, and administration of tolazoline, prostaglandin E1 and MgSO4 failed to reverse his hypoxemia. High ventilator settings were required, and pneumothoraces ensued. Airway resistance increased gradually with development of hypercapnia and deterioration of hypoxemia. Bradycardia unresponsive to resuscitation occurred, and he died at eight days of age. Postmortem examination of the lungs revealed increased peripheral connective tissue and diffuse extension of medial smooth muscle to the precapillary pulmonary arteries. Excessive antenatal muscularization of the peripheral pulmonary arteries and resultant increased vasoconstriction capacity may have played an important role in the pathogenesis of PPHN in this case.

Minimal role of hepatitis C virus infection in childhood liver diseases in an area hyperendemic for hepatitis B infection

To investigate the role of hepatitis C virus (HCV) in childhood liver disease in Taiwan, an area hyperendemic for hepatitis B, we studied antibody to HCV (anti-HCV) with a second generation enzyme immunoassay in 195 infants and children, including 96 hepatitis B surface antigen (HBsAg) positive children (66 with chronic hepatitis B, 23 children with hepatocellular carcinoma, and 7 with fulminant hepatitis B), 6 children with fulminant non-A, non-B hepatitis, 42 infants with neonatal hepatitis, 11 with biliary atresia, and 40 prospectively followed blood recipients. For comparison, another 748 apparently healthy children (from neonates to 12 years) were also screened for anti-HCV. The positive rate of anti-HCV was low in both apparently healthy children (0.13%) and patients with various liver disorders (0 to 4.4%) except fulminant hepatitis. The seropositive rate in 6 cases of non-A, non-B fulminant hepatitis was higher (16.7%) although the case number was too small. We conclude that HCV is generally not a major etiologic factor in the liver diseases of Taiwanese children.

Molecular identity of a sperm acrosome antigen recognized by HS-63 monoclonal antibody

The molecular identity of mouse sperm acrosome antigen recognized by HS-63 monoclonal antibody was analyzed by various biochemical, immunological and molecular biological methods. When its cognate antigen, MSA-63 was isolated from mouse testis by immunoaffinity chromatography, a group of protein spots with wide range of molecular sizes and isoelectric points were identified. Through previous studies, it was established that most of these protein spots were actin-like molecules co-purified with MSA-63 protein from mouse testis. To analyze the molecular size heterogeneity of the isolated MSA-63 proteins, rabbit antisera against a computer-predicted antigenic synthetic peptide (amino acid residue No. 160-171) and a recombinant glutathione S-transferase (GST) fusion protein (GST-63) were raised. These two antisera and those raised against the isolated MSA-63 protein were used as the probes in comparative Western blot assay, indirect immunofluorescent assay and enzyme-linked immunosorbent assay (ELISA). Using ELISA, antisera against GST-63 and computer-predicted antigenic synthetic peptides were shown to cross-react with affinity-isolated MSA-63 protein coated on microwells. However, little immunological cross-reactivity was observed between GST-63 fusion protein and the synthetic peptide. By using a Western blot assay, two major protein bands of 22 and 32 kDa, respectively were commonly detected on mouse testis homogenate strips by both anti-MSA-63 and anti-GST-63. In addition, anti-MSA-63 also recognized several protein bands with molecular masses greater than 35 kDa. The results of this study suggested that the molecular heterogeneity of MSA-63 protein isolated from mouse testis and sperm, is due to a series of post-translational modifications on a single gene product. These modifications may include glycosylations, proteolytic digestions and tight non-covalent associations with other testicular cytoskeletal proteins, such as actins.

The gene convergent to luxG in Vibrio fischeri codes for a protein related in sequence to RibG and deoxycytidylate deaminase

The nucleotide sequence of a convergent gene with the same bidirectional transcriptional terminator as the Vibrio fischeri lux operon has been determined. This gene codes for a polypeptide of 147 amino acids which is related in sequence to the polypeptide coded by the first gene (ribG) of the rib operon of Bacillus subtilis as well as deoxycytidylate deaminase of T4 bacteriophage and Saccharomyces cerevisiae. These results raise the possibility of a linkage between the regulation of the lux genes and riboflavin synthesis in Vibrio fischeri.

Safety and immunogenicity of hepatitis A vaccine in healthy adult volunteers

The immunogenicity and adverse reaction of an inactivated hepatitis A (HA) vaccine were investigated. Sixty healthy adult volunteers who lacked antibody to HA virus (anti-HAV) received three doses of vaccine containing 720 enzyme-linked immunosorbent assay (ELISA) units (EL.U) according to a 0, 1 and 6 month schedule. Blood tests for serum liver enzymes and anti-HAV were performed at screening 7 days prior to, and 1, 6 and 7 months after the first dose. Anti-HAV was tested by radio immunoassay and ELISA for titre determination. The seroconversion rates measured by ELISA were 98.3% (59/60) at months 1 and 6 and 100% at month 7. Sixty-one per cent (109/180) of the documented injections were followed by local symptoms, essentially mild soreness at the site of injection; and 22.2% (40/180) by minor general symptoms including malaise, fatigue and lethargy. It is concluded that HA vaccine is highly immunogenic and safe. It may replace immunoglobulin as an effective method of preventing HA virus infection in adults.

Electron microscopic immunolocalization of a conserved sperm acrosomal antigen recognized by HS-63 monoclonal antibody

HS-63 monoclonal antibody was shown to react with a sperm-specific acrosomal antigen from spermatozoa of a variety of mammalian species. Indirect immunofluorescence showed that HS-63 was associated with acrosome-intact sperm after sperm had been fixed with methanol. Electron microscopy (EM) was employed to determine the ultrastructural localization of this sperm antigen. When the immunogold labelled goat anti-mouse IgG was used as a probe, we demonstrated that HS-63 monoclonal antibody did not bind to the freshly prepared human spermatozoa. However, gold particles were observed in the intra-acrosomal region, when the spermatozoa had been pre-treated with 0.5% Triton X-100 prior to incubation with HS-63. We further observed that the immunogold did not stain the inner acrosome membrane when the spermatozoa became acrosome-reacted. A good correlation was obtained between the percentage of spermatozoa which did not react with HS-63 as determined by indirect immunofluorescence assay and that of acrosome-reacted spermatozoa as quantitated by electron microscopy. The results of this EM study were consistent with those obtained by indirect immunofluorescence assay and both indicated that HS-63 reacts only with the capacitated and acrosome-intact spermatozoa. Therefore, HS-63 monoclonal antibody is a useful probe for rapid evaluation of acrosomal status in human spermatozoa.

Effects of hyperthermia on the nucleolar proteins in tumour cells

The effects of hyperthermia at 41 degrees C and 43 degrees C on the nucleolar protein B23 in Ehrlich ascites tumour (EAT), human glioblastoma U-87 MG and U-373 MG cell lines were studied. Cellular localization of protein B23 was detected by an immunofluorescence technique using monoclonal antibody against protein B23. Diminution of fluorescence in the nucleoli occurred when the cells were treated at high temperature. The decrease in fluorescence level depends on the treatment temperature and duration. Among the three cell lines studied, the U-373 MG glioblastoma was the least responsive to hyperthermia followed by the U-87 MG glioblastoma. The decrease in nucleolar fluorescence of the EAT cells treated at 41 degrees C and 43 degrees C correlated with their subsequent cell survival. Dispersion of the nucleolar argyrophilic granules occurred in EAT cells after heating at 43 degrees C for 1 h. The possible implication of such effect is discussed in relation to the heat-sensitive elements in the nucleolus.

Depletion of alveolar macrophages by liposome-encapsulated dichloromethylene diphosphonate

Alveolar macrophages (AM) play an important role in lung biology. In this study, we demonstrated that tracheal insufflation of liposome-encapsulated dichloromethylene diphosphonate (Cl2MDP-liposome) selectively depleted AMs in rats. Insufflation of a single dose of Cl2MDP-liposomes (80 microliters containing 1.34 mumol of Cl2MDP) but not liposomes containing phosphate-buffered saline resulted in > 70% depletion of AMs starting within 1 day and lasting for > 5 days after insufflation. There was a slight but significant intraalveolar inflammatory response. Insufflation of Cl2MDP also resulted in depletion of AMs; however, it caused cytoplasmic edema of alveolar epithelial cells as well. Depletion of AMs by Cl2MDP-liposomes markedly reduced the endotoxin-induced neutrophil (polymorphonuclear lymphocyte) recruitment and the release of tumor necrosis factor into the alveolar space, suggesting that endotoxin-induced neutrophil recruitment and tumor necrosis factor release were dependent on AMs. This AM-depleted animal model will be useful for studying the in vivo functions of AMs and their role in various physiological and pathological conditions.