Response to supplementary vaccination with recombinant or plasma hepatitis B vaccine in healthy non-responding children

Fifty-three children who failed to respond to four doses of plasma hepatitis B (HB) vaccine (anti-HBs titre < 10 IU l-1) were divided into two groups and received revaccination with either three doses of recombinant HB vaccine (10 micrograms/dose, by 0, 1, 6 month schedule; group A) or two additional doses of plasma HB vaccine (5 micrograms/dose, by 0, 1 month schedule; group B) respectively. Thirty-two vaccinees in group A had a response rate (with anti-HBs > 10 IU l-1) of 53.1% (17/32), 87.5% (28/32), and 100% (32/32) after first, second and third doses of the vaccine respectively. Twenty-one vaccinees in group B had a response rate of 61.9% (13/21) after two additional doses of plasma vaccine. High anti-HBs titres (> 1000 IU l-1) were noted in 50% of the vaccinees in group A after three doses of vaccine. Comparing anti-HBs response between group A and group B after two additional doses of HB vaccine, group A had a higher anti-HBs titre (geometric mean titre 104.7 IU l-1 versus 75.9 IU l-1) along with a better seroconversion rate (87.5 versus 61.9%). However, the differences in vaccine dose between the two groups may also be a contributory factor. Our findings indicate that three doses of recombinant HB vaccine were invariably effective in eliciting a good immune response in previous non-responders to the four doses of plasma HB vaccine. Therefore, it is speculated that these young vaccinees who did not respond to four doses of plasma HB vaccine may not be real non-responders, but hyporesponders.

Productive infection of human endometrial stromal cells by human cytomegalovirus

Cultured endometrial stromal cells were susceptible to productive human cytomegalovirus (HCMV) infection. Infection of endometrial stromal cells resulted in pronounced cytopathic effects including cell rounding and aggregation, fusions, and some lysis, although not in the synchronous fashion observed in infected fibroblasts. The aggregation events were reminiscent of normal endometrial stromal cell responses to cyclical estrogen/progesterone levels. Immunofluorescence analysis demonstrated expression of viral gene products suggesting a productive virus infection. One-step growth analysis showed that infectious virus was produced but the titers were two logs lower than those obtained in fibroblasts even though HCMV DNA accumulated to similar levels in both cell types. In contrast, viral DNA replication was greatly reduced in endometrial stromal cells immortalized with a temperature-sensitive SV40 large T gene at both permissive and nonpermissive temperatures. A more detailed analysis of viral gene expression by Northern blotting revealed earlier appearances and greater initial levels of viral transcripts in endometrial stromal cells. No HCMV gene expression was observed at 120 hpi in these cells even though half of the cells were still intact and cellular gene expression was functional. Since this was the time of peak virus production, it seems plausible that reduced viral gene expression at late times p.i. was a major contributor to the reduced titers observed in endometrial stromal cells. These in vitro results coupled with in vivo observations by others of endometritis associated with HCMV suggest that further investigation into the effects of HCMV on the endometrium is warranted.

Kimura's disease--report of four cases

Kimura's disease is a rare benign condition that occurs predominantly in Oriental young people. The patients displayed a variety of manifestations such as painless, tumor-like masses in the head and neck regions, or in the salivary glands with associated lymphadenopathy. They are sometimes initially mistaken for malignant tumors, resulting in improper management. We present four cases of Kimura's disease and a comprehensive review of the literature to increase awareness and alert surgeons and pathologists to consider the possibilities of this disease, especially in Oriental patients having peripheral blood eosinophilia and/or elevated serum IgE.

Cytomegalovirus-induced persistent mononucleosis in an infant

Chronic mononucleosis has recently gained much attention in the literature. Almost all cases of this new syndrome have been ascribed to persistent Epstein-Barr virus infection. However, a case presented with infantile chronic mononucleosis syndrome caused by persistent cytomegalovirus infection. Transient clonal chromosomal change was noted during follow-up.

Freezing of mammalian livers with glycerol and antifreeze proteins

We have tested a protocol that uses a new cryoprotective solution for preserving mammalian livers in a frozen state. This protocol is based upon our studies on the mechanisms that freeze tolerant animals use to survive freezing in nature. The cryoprotective solution contains glycerol and antifreeze proteins, both of which are found in freeze tolerant animals. Whole rat livers were frozen to -3 degrees C, maintained at that temperature for 6 hours and then warmed to 37 degrees C. Post thawing bile production and microscopic analysis of tissue slices were used to verify liver function and tissue morphology. We conclude that antifreeze proteins used in the concentrations chosen here have a protective effect on the whole liver during freezing.

Riboflavin synthesis genes are linked with the lux operon of Photobacterium phosphoreum

Four genes immediately downstream of luxG in the Photobacterium phosphoreum lux operon (ribEBHA) have been sequenced and shown to be involved in riboflavin synthesis. Sequence analyses and complementation of Escherichia coli riboflavin auxotrophs showed that the gene products of ribB and ribA are 3,4-dihydroxy-2-butanone 4-phosphate (DHBP) synthetase and GTP cyclohydrolase II, respectively. By expression of P. phosphoreum ribE in E. coli using the bacteriophage T7 promoter-RNA polymerase system, ribE was shown to code for riboflavin synthetase, which catalyzes the conversion of lumazine to riboflavin. Increased thermal stability of RibE on expression with RibH indicated that ribH coded for lumazine synthetase. The organization of the rib genes in P. phosphoreum is quite distinct, with ribB and ribA being linked but separated by ribH, whereas in E. coli, they are unlinked and in Bacillus subtilis, RibB and RibA functions are coded by a single gene.

Use of the translational mobility of a plasma membrane protein to assess fertilization of mouse oocytes and viability of mouse zygotes and two-cell embryos

The fluorescence photobleaching recovery (FPR) technique was used to measure the translational mobility of a glycoprotein recognized by the monoclonal antibody (mAb) S75 in plasma membranes of mouse oocytes, zygotes, and two-cell embryos. Glycoprotein fractional mobility (f) was significantly decreased in membranes of unfertilized oocytes compared to zygotes or two-cell embryos (f values, 46 +/- 2 and 65 +/- 2%, respectively; p < 0.0001). Reduced apparent glycoprotein mobility was also observed in morphologically degenerated zygotes and two-cell embryos compared to viable zygotes and two-cell embryos (f values, 8 +/- 1 and 60 +/- 3%, respectively; p < 0.0001). These results indicate that the FPR technique can be used to assess oocyte fertilization and preimplantation embryonic viability. This method may be useful in the evaluation of embryonic viability following in vitro fertilization and in the detection of toxic effects of novel compounds on embryonic development.

Protein synthesis and ecdysteroidogenesis in prothoracic glands of the tobacco hornworm (Manduca sexta): stimulation by big prothoracicotropic hormone

The 28-kDa size variant of prothoracicotropic hormone (big PTTH) stimulates ecdysteroidogenesis by prothoracic glands of Manduca sexta. In the present studies, big PTTH stimulated in vitro incorporation of [35S]methionine into proteins of prothoracic glands from Day 7 last instar larvae. In 2-hr incubations, big PTTH elicited an approximately 2-fold increase in total protein-specific activity. The effect appeared to be tissue specific, as big PTTH had no effect on incorporation of label into proteins of control tissue (fat body). Electrophoretic separation of tissue homogenates, followed by autoradiography and densitometric analysis, revealed increased incorporation of radiolabel into numerous glandular proteins. The result suggested that the effect of big PTTH was a general stimulation of protein synthesis, not specific stimulation of a subset of glandular proteins. Big PTTH-stimulated ecdysteroidogenesis was inhibited by cycloheximide, indicating that the increase in protein synthesis is a requisite for enhanced hormone production. Analysis of gland incubation media revealed numerous radiolabeled proteins. The effect of big PTTH on incorporation of [35S]methionine into media proteins was considerably more variable than the effect of big PTTH on tissue incorporation. The result is consistent with the hypothesis that prothoracic glands may release proteins in addition to ecdysteroids.

The nitric oxide donor, sodium nitroprusside, increased intranuclear and cytosolic free calcium concentration in single PU5-1.8 cells

In the present study, the effect of sodium nitroprusside (SNP), a nitric oxide (NO) releasing agent, on the intracellular free calcium concentration ([Ca2+]i) was studied. Our results demonstrate that SNP could increase [Ca2+]i in single PU5-1.8 cells, a murine macrophage cell line, as determined by confocal laser scanning microscope with calcium green-1 fluorescent probe. In the presence of hemoglobin, a NO scavenger, the effect of SNP on the Ca2+ level was suppressed. Our data also show that the intranuclear Ca2+ ([Ca2+]n) was always higher than those in cytosol. Stimulation of cells with 1mM SNP induced an immediate increase of [Ca2+]n with a delayed rise of cytosolic Ca2+ ([Ca2+]c). Interestingly, when cells were subsequently treated with 2mM SNP, an increase of [Ca2+]c with a similar pattern to the rise [Ca2+]n was observed. In Ca(2+)-free buffer, SNP also raised the [Ca2+]n and [Ca2+]c. When Ca2+ was added to the buffer, a second peak of [Ca2+]n and several spikes of [Ca2+]c were observed. These results thus indicate that 1) NO may increase both [Ca2+]n and [Ca2+]c in PU5-1.8 cells; 2) the increase of [Ca2+]n requires both internal and external Ca2+. Moreover, the diverse responses in these cells suggest that the regulation of Ca2+ in these areas may be different.

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.