Nucleated erythrocytes in maternal blood: quantity and quality of fetal cells in enriched populations

The discovery of nucleated erythrocytes in maternal circulation provides a potential source for non-invasive prenatal diagnosis. We have evaluated the use of a three-stage procedure to determine the number of cells that are of fetal rather than maternal origin. First, monoclonal antibodies specific for CD45 and CD14 were used in conjunction with a magnetic (MACS) column to deplete unwanted leukocytes from maternal blood. This was followed by a positive MACS enrichment for nucleated erythrocytes, using an anti-CD71 (transferrin receptor) monoclonal antibody. To discriminate between fetal nucleated erythrocytes and those of maternal origin, enriched fractions were simultaneously stained with an anti-fetal haemoglobin (HbF) antibody and hybridized with probes specific for X and Y chromosomes. Samples were then subjected to blind analysis along with negative control samples from non-pregnant volunteers. Using this dual analysis, we were able to determine that less than one nucleated erythrocyte per ml of maternal blood was of fetal origin. Small numbers of these fetal cells were found in 87.5% of pregnancies, ranging from 6 to 35 weeks gestational age. Comparison of HbF and X/Y probe data also suggests that the fetal cells are less suitable for fluorescence in-situ hybridization (FISH) analysis than similar preparations from other sources.

Glucose metabolic correlates of continuous performance test performance in adults with a history of infantile autism, schizophrenics, and controls

Twenty-five schizophrenic patients, fourteen adults with a history of infantile autism, and twenty normal controls performed a test of sustained attention, the degraded stimulus continuous performance test (CPT), during the 35 minute 18-fluoro-2-deoxyglucose uptake period preceding positron emission tomographic (PET) scan acquisition. This is the first analysis comparing correlations between glucose metabolic rate (GMR) for selected regions and CPT performance. CPT performance differed in controls and schizophrenics, but autistics did not differ from either group. In controls and schizophrenic patients, task performance correlated with GMR in medial superior frontal gyrus and lateral inferior temporal gyrus, suggesting that activation of those regions is important in the normal performance of the task and that damage to those regions, which also showed low GMR in schizophrenics, contributes to the attentional dysfunction in schizophrenia. Also, schizophrenics showed negative correlations of task performance with anterior cingulate activity suggesting that overactivity of that region, which is involved in mental effort and whose GMR was low in our larger study of schizophrenia, impairs task performance in schizophrenics. Autistic patients showed negative correlations of medial frontal cortical GMR with attentional performance, suggesting that neuronal inefficiency in that region may contribute to poor performance.

Acute relapsing hepatitis A in Taiwan--a rare event not related to multiple viral infection: a report of two cases

From 1981 to 1993, 40 cases of acute type A viral hepatitis were reviewed and 2 cases (5%) of relapsing hepatitis were reported here. One case relapsed two weeks after remission and the other relapsed three weeks after remission, both had benign courses and recovered within four months. They were negative for serum hepatitis B surface antigen and hepatitis B core IgM antibodies. The serum autoantibodies, hepatitis C antibodies and hepatitis E antibodies were all negative during relapse. In summary, relapsing hepatitis A is rare in Taiwan and it is not related to multiple viral infections.

Randomized controlled trial of recombinant interferon-alpha 2b in the treatment of Chinese patients with chronic hepatitis C

To evaluate the efficacy of recombinant interferon (IFN) alpha 2b in the treatment of Chinese patients with chronic hepatitis C, a randomized controlled trial was conducted in 50 chronic hepatitis C patients: 25 patients received 3 million units of subcutaneously injected recombinant IFN-alpha 2b three times per week for 6 months, and 25 patients received no specific treatment were used as controls. At the end of the IFN treatment, 19 patients (76%) in the IFN-treated group normalized serum ALT compared with only 6 patients (24%) in the control group (p < 0.01). Relapse within 6 months after the completion of treatment occurred in 13 IFN-treated patients (68%). Normalized serum ALT was seen in 6 patients (24%) in the IFN-treated group and 1 patient (4%) in the control group 6 months after discontinuation of IFN therapy (p = 0.10). The presence of serum hepatitis C virus (HCV) RNA measured by reverse transcription-polymerase chain reaction was detected at the end of the IFN treatment in all 13 patients who relapsed after cessation of therapy. In only 3 of 25 IFN-treated patients (12%) was the presence of serum HCV RNA not detectable at the end of the IFN treatment or 6 months after cessation of therapy. No patient in the control group had undetectable serum HCV RNA during the study period. Using multivariate logistic regression analysis, the low pretreatment levels of HCV RNA, measured by a quantitative branched DNA amplification assay, was the only independent predictor of a sustained response to IFN therapy (p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and radiological pictures of hepatocellular carcinoma with intracranial metastasis

Hepatocellular carcinoma (HCC) with extrahepatic spreading is not uncommon. In order to delineate the clinical and radiological pictures of HCC with intracranial metastasis, 33 documented cases were analysed. Eighteen had brain parenchymal metastasis without skull involvement; the other 15 cases disclosed skull metastasis with brain invasion. The underlying HCC are mainly of expanding (13/33, 39.4%) and multifocal (13/33, 39.4%) types. Eighteen cases (18/33, 54.5%) had mental changes not related to hypoglycaemia or hepatic encephalopathy. Eighteen cases (18/20, 90%) disclosed hyperdense mass lesions by non-contrast computed tomography (CT) scans and 17 cases showed homogeneous enhancement (17/22, 77.3%) by post-contrast CT images. In the non-skull involved group, five cases (5/12, 41.7%) disclosed ring-shape enhancement and 14 cases (14/16, 87.5%) had perifocal oedema, which were not seen in the skull involved group. Eight cases (8/33, 24.2%) presented as intracerebral haemorrhage. Twelve (12/33, 36.4%) died of brain herniation. Most (14/18, 77.8%) non-skull involved cases had simultaneous lung metastasis without bony metastasis, while the skull involved group often (10/15, 66.7%) disclosed extracranial bony metastasis without lung metastasis. The difference in extracranial metastasis was statistically significant (P < 0.05). The multivariate survival analysis disclosed that lower lactate dehydrogenase level (< or = 316 U/L, P = 0.029) and treatments (surgery or radiation, P = 0.001) were positively associated with longer survival. In conclusion, HCC with intracranial metastasis is symptomatic and life-threatening. Half the cases may come from pulmonary metastasis and the other half may be from bony metastasis. Brain irradiation or surgery can prolong their survival.

Injection with nondisposable needles as an important route for transmission of acute community-acquired hepatitis C virus infection in Taiwan

A prospective case-controlled study was conducted in order to determine the transmission route of community-acquired hepatitis C virus (HCV) infection in Taiwan. Thirty-eight consecutive patients (25 men and 13 women) with acute community-acquired HCV infection and 76 age (within 3 years)- and sex-matched healthy control subjects without HCV infection were enrolled. Serum anti-HCV was tested by second generation immunoassay. The sera of 26 family members from 12 families of index patients were also tested for anti-HCV. A questionnaire covering the history of blood transfusion, surgery, intravenous drug abuse, prostitute contact, dental procedures, injection, acupuncture, tattooing, and ear-piercing was conducted among patients and control subjects. Univariate analysis revealed injection with nondisposable needles was an independent risk factor (P = 0.02, odds ratio = 4.17, 95% confidence interval = 1.24-14.47) associated with HCV infection. Other risk factors were not significant. Only 2 (7.7%) family members of index patients had an anti-HCV. In conclusion, more vigorous effort to prohibit the use of nondisposable needles should be promoted to interrupt the spread of community-acquired HCV infection in Taiwan. Of note, a significant number of patients (34.2%) contracted HCV infection without identifiable risk factors. Unidentified routes need to be investigated.

Non-sialate inhibitor of influenza A/WSN/33 neuraminidase

An N1 strain of influenza A virus neuraminidase (A/WSN/33 NA) was purified and used to screen for inhibitors. As a result, a well-known tuberculostatic, 4'-formylacetanilide thiosemicarbazone (or thiacetazone), was identified. Thiacetazone is a non-sialate compound and inhibits the enzyme in a noncompetitive manner with respect to the substrate sialic acid. Mechanistic studies indicate that the inhibition was due to the competition of thiacetazone with Ca2+, which maintains N1 neuraminidase in an active conformation. The Ki for the inhibition was estimated to be about 4 microM. Equilibrium exchange experiments revealed that when purified A/WSN/33 NA was incubated with 5 microM 45CaCl2, 2 mol of 45Ca2+ ion was exchanged into each mole of NA tetramer and subsequently displaced from the enzyme upon the introduction of the inhibitor. Inhibition of plaque formation by thiacetazone in an MDCK cell culture that had been infected with the influenza A/WSN/33 virus was demonstrated. Thiacetazone was highly specific for A/WSN/33 neuraminidase, since little effect was noted when it was tested against NAs from the other strains of influenza virus or from bacteria. This compound might represent a group of non-sialate inhibitors of influenza NA that bind to a noncatalytic or an allosteric site on the enzyme.

Transcatheter arterial embolization for hepatocellular carcinoma with portal vein thrombosis

In order to evaluate the possible benefits of transcatheter arterial embolization (TAE) in hepatocellular carcinoma (HCC) patients with peripheral portal vein thrombosis, 96 consecutive HCC cases with peripheral portal vein thrombosis were analysed. Of them, 35 cases received TAE and 61 cases did not. Most (77.8%) of the TAE-treated cases showed decreased alpha-fetoprotein (AFP) levels after treatment, but 57.1% of them suffered another rise in AFP levels and subsequently died. One patient (2.8%) developed progressive jaundice after TAE and died within 1 month, while four of the non-TAE cases died within 1 month after diagnosis. In general, TAE is safe for HCC patients with peripheral portal vein thrombosis. In addition, using Cox's regression model for multivariate survival analysis, serum total bilirubin (< or =, > 2 mg/dL; P = 0.0254), AFP (< or = 3155 ng/mL, > 3155 ng/mL; P = 0.0002) and treatments (TAE, non-TAE; P = 0.0059) were found to affect their prognosis. There was significant difference in survival between TAE and non-TAE groups, the 6 month, 1 year and 2 year survival rates were 91.4 versus 62.3%, 51.4 versus 26.2% and 17.1 versus 4.9% (P = 0.0017). The median survival times of TAE and non-TAE groups were 10.3 versus 3.7 months, respectively. Though TAE only provided palliative treatment, it did prolong survival in HCC patients with peripheral portal vein thrombosis.

Topographic analysis of EEG photic driving in normal and schizophrenic subjects

In a 19-channel EEG photic driving paradigm the steady-state evoked response was studied in schizophrenic patients and normal controls. Seventeen drug-free patients and 15 normal controls were compared. Schizophrenic patients had lower EEG photic driving in the alpha range, particularly in the high alpha frequency band (p = 0.08). Topographic analysis revealed that the group differences were primarily located in the mid-frontal, central and parietal areas (p < 0.05). Temporal and lateral frontal lobe alpha remained the same in the two groups. Separate analysis of eye movement (EM) showed an opposite effect on the alpha-frequency photic driving as compared to that on the resting alpha EEG. EM decreased the resting alpha EEG and increased the photic driving. This finding suggested that the lower EEG photic driving in the schizophrenic patients could not be explained by the eye movement artifact. We hypothesize that the 10 Hz range photic driving that reflects the intrinsic EEG spindle generation in the thalamus may play an important role in the psychophysiology of schizophrenia.

DNA-based X-enriched sperm separation as an adjunct to preimplantation genetic testing for the prevention of X-linked disease

We report the world's first clinical pregnancy resulting from DNA-based enrichment for X-bearing human spermatozoa, for prevention of X-linked hydrocephalus. Sperm separation was followed by embryo biopsy and nested multiplex polymerase chain reaction (PCR) for gender determination. Enriched populations of X-bearing spermatozoa ranging from 80 to 89% pure as determined by fluorescence in-situ hybridization (FISH) resulted in in-vitro fertilization (IVF) rates indistinguishable from normal IVF procedures (65%). In two separate biopsy procedures, 7/9 and 15/16 of the resulting embryos were determined to be female by multiplex PCR. Embryo transfer resulted in a karyotypically normal female fetus. This technique should be widely applicable to gender selection for the prevention of genetic disorders.

Preparation of ethylcellulose microcapsules containing theophylline by using emulsion non-solvent addition method

A new technique in which ethylcellulose microcapsules containing theophylline (a water-soluble drug), prepared using the O/W emulsion non-solvent addition method, was developed. Toluene-cyclohexane was chosen as the solvent-nonsolvent system. The effects of four process variables, polymer concentration, species and concentration of emulsifier, and core to wall ratio, on the micromeritic properties and release behaviour of microcapsules were investigated. The results indicated that theophylline can be microencapsulated with a high yield (low drug loss) by using the O/W emulsion non-solvent addition method with the toluene-cyclohexane system. The particle size and drug content of the microcapsules were influenced by these process variables. The morphology of microcapsules was also affected by the core to wall ratio. The release pattern of the microcapsules was found to have similar properties to the release of a drug from a spherical homogeneous matrix. The effective diffusion coefficient increased with increasing core to wall ratio.

Detection of antibody to M2 mitochondrial antigen in Chinese patients with primary biliary cirrhosis

BACKGROUND

Antimitochondrial antibodies (AMA) are present in more than 90% of patients with primary biliary cirrhosis (PBC). However, AMA are not specific for PBC; they can be observed in nonhepatic disease. It has been reported that antibody of M2 mitochondrial antigen (anti-M2) is specific for PBC. The aim of the present study is to clarify the role of anti-M2 in the diagnosis of PBC.

METHODS

Sera from 27 patients with PBC, 62 normal subjects, 18 patients with chronic hepatitis B and 30 patients with chronic hepatitis C were obtained for the detection of anti-M2 and AMA. The anti-M2 assay was performed by enzyme immunoassay (EIA) and the AMA test was performed by indirect immunofluorescent method.

RESULTS

Twenty-four (88.9%) of the serum specimens from the patients with PBC and one (0.9%) of the 110 serum specimens from the non-PBC groups were positive for AMA. In contrast, twenty-five (92.6%) of the 27 PBC sera and five (4.5%) of the 110 non-PBC sera were positive for anti-M2. Most of the PBC sera contained high titers of anti-M2 and all the false-negative specimens disclosed low titers of anti-M2.

CONCLUSIONS

Although the anti-M2 assay used in the present study seemed not superior to the conventional AMA test in the sense of specificity, it had the advantage of being able to provide quantitative results. Since the presence of high titer anti-M2 is very specific for PBC, this assay may have a role in the diagnosis of equivocal PBC.

Natural history of hepatitis D viral superinfection: significance of viremia detected by polymerase chain reaction

BACKGROUND/AIMS

Polymerase chain reaction (PCR) is very sensitive. The aim of the study was to reevaluate viral replication in hepatitis D virus (HDV) superinfection by PCR.

METHODS

HDV and hepatitis B virus (HBV) were detected by PCR in 185 patients.

RESULTS

The acute hepatitis group had the highest detection rate of HDV RNA compared with chronic hepatitis, cirrhosis, hepatocellular carcinoma, and remission groups (63 of 64 vs. 35 of 47, 17 of 23, 19 of 30, and 7 of 21) and the highest alanine aminotransferase (ALT) levels (mean, 1741 U/L vs. 266 to 27 U/L; P < 0.05). The detection rate of HBV DNA was the lowest in the acute group (41%) compared with 66%, 70%, 80%, and 57% in the remaining groups (P < 0.02). At the chronic stage, 13%-25% of cases had HDV RNA, and 30%-48% of cases had HBV DNA detected by PCR but not by traditional method. HDV RNA was associated with ALT levels in horizontal and longitudinal analyses.

CONCLUSIONS

HDV superinfection may be divided into the following three phases: acute phase, active HDV replication and suppression of HBV with high ALT levels; chronic phase, decreasing HDV and reactivating HBV with moderate ALT levels; and late phase, development of cirrhosis and hepatocellular carcinoma caused by replication of either virus or remission resulting from marked reduction of both viruses.

A positron emission tomography [18F]deoxyglucose study of developmental stuttering

Positron emission tomography using [18F]deoxyglucose (FDG) as a marker of regional brain metabolism was used to investigate the neural substrate of stuttering. Four patients with severe developmental stuttering were studied while reading aloud to another person (stuttering condition) and while reading aloud in unison with someone else (non-stuttering condition). The patients were also compared with four normal controls reading aloud by themselves. In the stuttering condition, significant decreases in regional glucose metabolism in Broca's area, Wernicke's area and frontal pole were seen compared with themselves while not stuttering. These differences were also seen in stuttering condition compared with normal controls. Significantly lower left caudate metabolism was seen in patients during both stuttering and non-stuttering conditions compared with normal controls. A circuit for stuttering is proposed based on these findings.

Cerebral metabolism during propofol anesthesia in humans studied with positron emission tomography

BACKGROUND

Although the effects of propofol on cerebral metabolism have been studied in animals, these effects have yet to be directly examined in humans. Consequently, we used positron emission tomography (PET) to demonstrate in vivo the regional cerebral metabolic changes that occur in humans during propofol anesthesia.

METHODS

Six volunteers each underwent two PET scans; one scan assessed awake-baseline metabolism, and the other assessed metabolism during anesthesia with a propofol infusion titrated to the point of unresponsiveness (mean rate +/- SD = 7.8 +/- 1.5 mg.kg-1.h-1). Scans were obtained using the 18fluorodeoxyglucose technique.

RESULTS

Awake whole-brain glucose metabolic rates (GMR) averaged 29 +/- 8 mumoles.100 g-1.min-1 (mean +/- SD). Anesthetized whole-brain GMR averaged 13 +/- 4 mumoles.100 g-1.min-1 (paired t test, P < or = 0.007). GMR decreased in all measured areas during anesthesia. However, the decrease in GMR was not uniform. Cortical metabolism was depressed 58%, whereas subcortical metabolism was depressed 48% (P < or = 0.001). Marked differences within cortical regions also occurred. In the medial and subcortical regions, the largest percent decreases occurred in the left anterior cingulate and the inferior colliculus.

CONCLUSION

Propofol produced a global metabolic depression on the human central nervous system. The metabolic pattern evident during anesthesia was reproducible and differed from that seen in the awake condition. These findings are consistent with those from previous animal studies and suggest PET may be useful for investigating the mechanisms of anesthesia in humans.

High-resolution magnetic resonance imaging evaluation of blood-retinal barrier integrity following transscleral diode laser treatment

OBJECTIVE

To compare the effects of contact transscleral diode laser treatment and retinal cryotherapy on blood-retinal barrier integrity with the use of high-resolution magnetic resonance imaging techniques with constant infusion of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA).

METHODS

Transscleral diode laser photocoagulation and retinal cryotherapy were used to treat equivalent areas of the inferior retinal periphery of pigmented rabbits. Magnetic resonance imaging time-course studies with measurement of signal enhancements due to Gd-DTPA leakage were conducted 2 and 15 days following treatment.

RESULTS

Two days following treatment, cryotherapy-treated eyes exhibited a mean (+/- SD) effective Gd-DTPA permeability coefficient of 4.6 +/- 0.8 x 10(-6) cm/s; in comparison, diode laser-treated eyes exhibited 1.6 x 1.4 x 10(-6) cm/s effective permeability. Significant decreases in the effective permeability were also noted 15 days after treatment in both groups.

CONCLUSIONS

Transscleral contact probe diode laser photocoagulation induces less disruption of the blood-retinal barrier than does conventional cryotherapy. In addition, the continuous infusion method of Gd-DTPA delivery is a reliable and easily interpretable alternative to the commonly used bolus injection approach.

Autonomous growth in serum-free medium and production of hepatocellular carcinomas by differentiated hepatocyte lines that overexpress transforming growth factor alpha 1

Transforming growth factor alpha (TGF-alpha) is a polypeptide closely associated with hepatocyte proliferation in vivo and in vitro. In order to investigate the mechanisms by which TGF-alpha contributes to hepatocyte replication and transformation, we isolated hepatocytes from mice bearing a human TGF-alpha transgene and examined their growth properties and gene expression in defined, serum-free culture. The transgenic hepatocytes continued to overexpress human TGF-alpha mRNA and peptide, and were able to proliferate without exogenous growth factors in primary culture, in contrast to nontransgenic mouse hepatocytes. In short-term culture the transgenic hepatocytes underwent 1 wave of DNA replication at 72-96 h in culture before senescing, similar to nontransgenic hepatocytes supplemented with epidermal growth factor. Constitutive expression of TGF-alpha rendered the transgenic hepatocytes unresponsive to further growth stimulation by exogenous TGF-alpha, as well as other mitogens such as epidermal growth factor and hepatocyte growth factor. However, it did not alter their sensitivity to growth inhibition by TGF beta 1, 2 and 3. The addition of nicotinamide to the culture medium enabled both transgenic and epidermal growth factor-supplemented normal hepatocytes to replicate repeatedly and survive for > or = 2 months in primary culture while maintaining differentiated traits. From these long-term primary cultures of transgenic and nontransgenic hepatocytes, we established immortalized cell lines (designated TAMH and NMH lines, respectively). Both lines continued to express differentiated adult hepatocytic markers such as albumin, alpha-1-antitrypsin, transferrin, and connexin 26 and 32 mRNAs, but also expressed mRNAs for the oncofetal markers alpha-fetoprotein and insulin-like growth factor II. Unlike the near-diploid NMH hepatocyte line, the transgenic TAMH hepatocyte line was quasi-tetraploid, strongly expressed human TGF-alpha mRNA, and was highly tumorigenic in nude mice. Well-differentiated hepatocellular carcinomas developed in nude mice given injections of the TAMH line, and these appeared similar to the primary liver tumors seen in TGF-alpha transgenic mice with regard to histology and strong expression of mouse and human TGF-alpha, insulin-like growth factor II, and alpha-fetoprotein mRNAs. Our data show that TGF-alpha overexpression causes autonomous hepatocyte proliferation and contributes to neoplasia but that additional cellular alterations must occur for carcinogenesis. Inappropriate expression of insulin-like growth factor II may constitute one of these steps. The TGF-alpha transgenic mouse hepatocyte line TAMH appears to undergo transformation in a similar manner to that of hepatocytes overexpressing TGF-alpha in vivo, and should serve as an ideal system in which to study hepatocarcinogenesis.

Differential regulation of vitamin D receptor and intestinal calcium transport occurring during sexual maturation in the fowl (Gallus domesticus)

Quantitative measurements of intestinal vitamin D receptor (VDR) and calcium transport taking place in individual villus-attached enterocytes have been compared during the onset of sexual maturity to test for a direct involvement of VDR in controlling calcium transport across the chick small intestine. Chickens of all ages showed VDR to be present in crypt and villus enterocytes, the amounts of VDR declining only slightly during enterocyte migration from the crypts to the tips of villi. Calcium transport corrected for initial adsorption was lowest in the crypt and highest in villus tip enterocytes. These results are consistent with VDR initiation and possible later maintenance of calcium transport across differentiating enterocytes. The total amount of VDR determined along the crypt-villus axis was significantly less in immature 11-week-old compared with 17-week-old sexually mature non-laying and 25-week-old laying chickens. Calcium transport was significantly greater in 25-week-old compared with 17- and 11-week-old birds. This unexpected up-regulation of VDR in 17-week-old birds was not affected by dietary restriction of calcium. Increased VDR expression in 17-week-old sexually mature birds is probably initiated by estrogen acting indirectly to increase 1,25 (OH)2D3 production in the kidney. Increased calcium transport in 25-week-old laying chickens could involve estrogen interacting with estrogen receptors as well as 1,25 (OH)2D3 interacting with vitamin D receptors to promote gene transcription in the intestine.

Studies on the properties of ethylcellulose microcapsules prepared by emulsion non-solvent addition method in the presence of non-solvent in polymer solution

Ethylcellulose microcapsules containing theophylline were prepared by the O/W emulsion non-solvent addition method. Toluene-cyclohexane was chosen as a solvent-non-solvent pair. The effect of the non-solvent added to the polymer solution on the properties of microcapsules was investigated. The results indicated that the size distribution and drug content of microcapsules were slightly affected by the amount of non-solvent in polymer solution. However, the internal conformation of microcapsules was directly related to the amount of non-solvent added to the polymer solution. The greater the non-solvent to solvent ratio in polymer solution the larger the percentage of microcapsules having a hollow conformation. Dissolution studies showed that the release rate of theophylline from microcapsules increased with increasing amount of non-solvent added to the polymer solution, but the release pattern of microcapsules was not obviously changed.

Evaluation of the properties of ethylcellulose-cellulose triacetate microcapsules containing theophylline prepared by different microencapsulation techniques

Using cellulose triacetate as an added complementary coating material in preparing sustained-release ethylcellulose-cellulose triacetate microcapsules of theophylline, three microencapsulation techniques were investigated. Ethylcellulose-cellulose triacetate composite microcapsules, ethylcellulose-cellulose triacetate dual-walled microcapsules and ethylcellulose microcapsules containing cellulose triacetate matrices were prepared using the non-solvent addition phase separation method. The effects of cellulose triacetate on the release of theophylline from the different ethylcellulose-cellulose triacetate microcapsules were obtained from dissolution studies. The results showed that the release rates of ethylcellulose-cellulose triacetate microcapsules were slower than those obtained from the ethylcellulose microcapsules prepared with similar core to wall ratios. The ethylcellulose microcapsules containing cellulose triacetate matrices had longer release half-times and smaller surface areas than the other capsule preparation. The release patterns of theophylline from the different ethylcellulose-cellulose triacetate microcapsules fitted first-order kinetics. Scanning electron micrographs showed that the surfaces of various ethylcellulose-cellulose triacetate microcapsules were different from those of theophylline, cellulose triacetate matrices of cellulose triacetate microcapsules, and that the surface morphology of ethylcellulose-cellulose triacetate microcapsules was affected by the preparative method.

Experimental infection of an isolate of Taenia solium from Hainan in domestic animals

The present study was designed to determine the susceptibility of domestic animals to an isolate of Taenia solium from Hainan Province, People's Republic of China. A total of 162 cysticerci were recovered from two pigs and 21 from two dogs after experimental inoculation. Cats, goats and a calf were not susceptible to T. solium. Cysticerci were recovered mainly from muscles of the pigs and all were alive. The remainder were in the liver and only one was alive. In the dog, all cysticerci were recovered from the muscles and all were alive.

Localisation of vitamin D receptor in normal human duodenum and in patients with coeliac disease

Immunocytochemistry using a specific monoclonal antibody 9A7 gamma was used to identify receptors for calcitriol (1,25 (OH)2 D3), the active metabolite of vitamin D, in sections of duodenal mucosa. Specific staining for vitamin D receptors was largely restricted to nuclei of enterocytes lining crypts in duodenal biopsy specimens from normal mucosa. Vitamin D receptors were also abundant in crypts from duodenal mucosa in coeliac disease patients with mucosal damage and villous atrophy. In contrast, alkaline phosphatase, a vitamin D regulated protein, was absent from crypts but present on brush borders of normal villi, and on surface enterocytes in coeliac disease. Oestrogen receptor could not be identified in duodenal mucosa. These findings suggest that calcium malabsorption in coeliac disease does not result from the absence of vitamin D receptors, but rather from reduction in vitamin D regulated proteins and functions essential for active calcium absorption that are located in the enterocytes of the villi.

Overexpression of transforming growth factor-alpha causes liver enlargement and increased hepatocyte proliferation in transgenic mice

Transforming growth factor-alpha (TGF-alpha) expression is associated with hepatocyte DNA replication both in vivo and in culture. Our previous work using TGF-alpha transgenic mice showed that constitutive overexpression of this growth factor in the liver causes hepatic tumors in 75 to 80% of the animals at 12 to 15 months of age. To understand the cellular events by which TGF-alpha overexpression leads to abnormal liver growth, we examined hepatocyte proliferative activity in young and old TGF-alpha transgenic mice and hepatocyte ploidy in normal, dysplastic, and neoplastic livers of these animals. At 4 weeks of age, transgenic mice had higher liver weights and liver weight/body weight ratios than non-transgenic mice of the same age and hepatocyte proliferative activity, measured by 3H-thymidine incorporation after 3- and 7-day infusion, proliferating cell nuclear antigen staining, and mitotic index determination, was 2 to 3 times higher than in controls. In both transgenic and non-transgenic mice hepatocyte proliferation declined with age but the decrease was much more pronounced in control animals, so that at 8 months of age, hepatocyte replication was 8 to 10 times higher in transgenic animals. Surprisingly, however, transgenic and non-transgenic mice at this age had similar liver weight/body weight ratios. Labeling studies done in 3-month-old animals revealed that hepatocyte turnover was much faster in transgenic than in control animals, suggesting that a homeostatic compensatory mechanism involving cell death tended to restore normal liver weight/body weight ratios in older transgenic mice. Ploidy analyses showed that at 4 weeks of age transgenic mice had a higher proportion of diploid and tetraploid hepatocytes and that the hepatocellular tumors which developed in TGF-alpha transgenic mice at 13 months of age contained a higher fraction of diploid hepatocytes than that present in adjacent tissue or in dysplastic livers. The results demonstrate that constitutive overexpression of TGF-alpha causes increased hepatocyte proliferation and liver enlargement in young animals and is associated with a delay in the establishment of hepatic polyploidy. These findings as well as the response of transgenic mice to partial hepatectomy show that constitutive overexpression of TGF-alpha initially caused increased but regulated hepatocyte proliferation which in older animals was compensated in part by a faster cell turnover. At 8 to 10 months of age, proliferative activity may become constitutive in some TGF-alpha expressing hepatocytes.(ABSTRACT TRUNCATED AT 400 WORDS)

Physiology of the lower eyelid retractors: tight linkage of the anterior capsulopalpebral fascia demonstrated using dynamic ultrafine surface coil MRI

Although the histologic anatomy of the lower eyelid retractors is well defined, the physiology of the lower retractors has been determined only by interference based on anatomic and clinical findings. In this study, in five normal subjects we investigated the physiology of the lower eyelid retractors utilizing dynamic high resolution magnetic resonance imaging (MRI) with a custom designed surface coil. Measurements of the excursion of the cornea, lower eyelid margin, and anterior edge of the inferior oblique muscle were made from scans taken in upgaze and downgaze. We found that the corneal movement was substantially greater than the movement of the eyelid margin, a finding that can readily be made clinically. A more important result was that the movement of the eyelid margin and the movement of the inferior oblique margin were similar in all cases. Thus, the length of the anterior capsulopalpebral fascia between the tarsus and inferior oblique muscle remains constant in downgaze, and the source of the stretch in the lower eyelid retractors lies in the posterior capsulopalpebral system, at the capsulopalpebral head. High resolution eyelid MR has great potential to allow investigation of essential aspects of normal and pathologic eyelid anatomy and physiology.

Effect of the solvent-non-solvent pairs on the surface morphology and release behaviour of ethylcellulose microcapsules prepared by non-solvent-addition phase separation method

Four solvent-non-solvent pairs (ethyl-acetate-cyclohexane, dichloromethane-cyclohexane, acetone-cyclohexane and dichloromethane-n-hexane) with different solubility parameter differences were chosen to prepare ethylcellulose microcapsules containing theophylline by using non-solvent-addition phase separation method. The results showed that the surface morphology and release behaviour of microcapsules were greatly affected by different solvent-non-solvent pairs. The surface of the microcapsules prepared from the system of high solubility parameter difference was more smooth than those from the systems of low solubility parameter difference. The release rate of the drug from microcapsules decreased with increasing solubility parameter difference of the preparative system. The determination of the wall thickness and porosity of the microcapsules could reasonably explain the release characteristics. The porosity of the microcapsules decreased with the increase of solubility parameter difference of the preparative system, but the wall thickness of the microcapsules showed a corresponding increase. The release of the drug from various ethylcellulose microcapsules fitted first-order kinetics with biphasic release profiles.

Optimal cement space for resin luting cements

Stainless steel dies, simulating 0 to 80 microns of die spacing, were seated into a machined brass crown with Phosphacap, Panavia EX, and C & B Metabond. The seating discrepancy after 60 seconds was measured to determine the optimal cement space for best seating for each agent. The most complete seating for crowns luted with zinc phosphate cement was observed when at least 40 microns of cement space was provided. C & B Metabond and Panavia required 30 microns of die spacing.

Clinical evaluation of erythrocytosis in patients with hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a common malignancy in southeast Asia and sub-Saharan Africa. During its clinical course, patients may manifest a variety of paraneoplastic syndromes, including erythrocytosis. However, there are few reports on the clinical and biochemical characteristics of HCC patients who manifest erythrocytosis. The purpose of this study is to evaluate the incidence of erythrocytosis in a large series of the Chinese patients with HCC, and to investigate the association of erythrocytosis with tumor volume and with serum levels of alpha-fetoprotein (AFP) and erythropoietin.

METHODS

Among 792 Chinese HCC patients who were seen during a 3-year period, we identified HCC patients with erythrocytosis as those with hemoglobin levels greater than 16.7 gm/dL (two standard deviations above the mean hemoglobin level of matched normal controls). The tumor size and serum levels of AFP and erythropoietin were evaluated in HCC patients with erythrocytosis to compare with HCC patients without erythrocytosis.

RESULTS

20 (2.5%) of 792 Chinese HCC patients presented with erythrocytosis. Nineteen of these 20 HCC patients were found to have either bi-lobar tumor involvement or a large tumor mass confined to one lobe of the liver. The estimated mean tumor volume of HCC patients with erythrocytosis was 50% of whole liver. When compared with HCC patients without erythrocytosis, the 20 HCC patients with high hemoglobin levels had significantly higher serum levels of AFP and erythropoietin (356,343 +/- 145,807 vs. 16,881 +/- 10,425 ng/mL, 135 +/- 45 vs. 25 +/- 4 mU/mL, respectively, p < 0.01).

CONCLUSIONS

Base on our findings, detection of erythrocytosis in a patient with HCC would indicate the presence of a large tumor burden, and high serum levels of both AFP and erythropoietin should be associated with this paraneoplastic syndrome.

Gonadal hormones and gonadotropin-releasing hormone (GnRH) alter messenger ribonucleic acid levels for GnRH receptors in sheep

GnRH regulates the synthesis and secretion of pituitary gonadotropins. The number of receptors for GnRH (GnRH-rec) can vary from 500 to 15,000-20,000/gonadotrope in ovine pituitary cultures after treatment with physiologically relevant combinations of gonadal hormones. This large range suggests that regulation of GnRH-rec expression may be an important control point in GnRH action at the pituitary level. Reported here are the changes in GnRH-rec mRNA associated with pituitary treatments (48 h) of 17 beta-estradiol (E), progesterone (P), and an enriched preparation of porcine follicular inhibin (IN). Northern blot analysis was used to detect 3 species of GnRH-rec mRNA in primary ovine pituitary culture [5.5 kilobases (kb; 32%), 3.6 kb (51%), and 1.4 kb (17%)]; all were changed in parallel by E, P, and IN. GnRH-rec mRNAs were increased 190% over control levels after treatment with either E or IN, and 400% with E and IN combined; when E and IN were added along with P, the increase was only 50% (P caused an 87% inhibition of E plus IN induction). The addition of P in the absence of any other treatment reduced levels of GnRH-rec mRNA by 50%. Studies were also conducted with GnRH agonists (GnRH-A) due to their widespread clinical use for down-regulating reproductive function in men and women. The addition of GnRH-A to cultures was as effective as P in blocking E plus IN induction of GnRH-rec mRNA. In vivo studies in wethers showed that 7 days of chronic treatment with GnRH-A decreased all sizes of ovine GnRH-rec mRNA by 84-89%. These data indicate that E, P, and IN change GnRH-rec levels at least in part by changing levels of GnRH-rec mRNAs. They also show that GnRH-A can almost entirely block E plus IN induction of GnRH-rec mRNA in vitro and decrease levels of GnRH-rec mRNA in vivo in wethers.

Multiple viral infection as the most common cause of fulminant and subfulminant viral hepatitis in an area endemic for hepatitis B: application and limitations of the polymerase chain reaction

We tested serum samples from 25 fulminant hepatitis and 7 subfulminant hepatitis patients for hepatitis A, B, C, D and E viral markers and nucleic acids by means of polymerase chain reaction to determine the role of each virus on such catastrophic events in an area endemic for hepatitis B. Of these 32 patients, 14 (44%) were hepatitis B virus carriers with hepatitis D virus superinfection (1 with hepatitis C virus infection), 3 others had coexisting hepatitis B virus and hepatitis C virus infections, 6 had reactivation of underlying chronic hepatitis B, 4 had acute hepatitis B, 2 had acute hepatitis C and 1 had acute hepatitis E. Pathogenesis in the remaining two cases was unclear. Serum hepatitis B virus DNA was detectable in most carriers without superinfection and in one third of those with superinfection detected on polymerase chain reaction (6 of 7 vs. 6 of 16, p < 0.05). Of the polymerase chain reaction-positive samples, only 17% yielded positive results on spot hybridization. Hepatitis B virus DNA was the only marker to indicate coexisting hepatitis B virus infection in one patient positive for hepatitis C virus antibody. Only three of the six hepatitis C virus-infected cases were positive for hepatitis C virus antibody; diagnoses in the remaining three were established by means of detection of hepatitis C virus RNA. Of the hepatitis D virus-infected patients, infection in only half was diagnosed by means of total hepatitis D virus antibody assay. Twelve (86%) were positive for anti-hepatitis D virus IgM and nine (64%) had detectable hepatitis D virus RNA on reverse transcription-polymerase chain reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Human IMP dehydrogenase catalyzes the dehalogenation of 2-fluoro- and 2-chloroinosine 5'-monophosphate in the absence of NAD

The ability of human type II inosine monophosphate dehydrogenase (IMPDH, EC 1.1.1.205) to catalyze the formation of xanthosine 5'-monophosphate (XMP) from C2 halogen-substituted analogs of IMP has been investigated. Adenosine deaminase was used to enzymatically synthesize 2-fluoroinosine and 2-chloroinosine from the 2-fluoro- and 2-chloroadenosine nucleoside analogs. Chemical phosphorylation yielded the corresponding 5'-nucleoside monophosphate derivatives. IMPDH catalyzes the conversion of both 2-fluoro- and 2-chloroinosine 5'-monophosphate (2-F- and 2-Cl-IMP) to XMP. The dehalogenation reactions proceed without nicotinamide adenine dinucleotide (NAD), the hydride acceptor required for the oxidation of IMP, the normal substrate of the enzyme. Formation of XMP from the 2-halo-IMPs was verified by UV absorption spectroscopy and by HPLC. Formation of XMP from 2-F-IMP yielded stoichiometric amounts of fluoride anion. IMP and XMP were competitive inhibitors toward 2-Cl-IMP in the dehalogenation reaction. Neither 2-F-IMP nor 2-Cl-IMP irreversibly inactivate IMPDH. Kinetic constants for the dehalogenation reactions have been determined and compared to the dehydrogenation reaction at 25 degrees C. (For 2-F-IMP: kcat = 0.058 s-1, Km = 62 microM. For 2-Cl-IMP: kcat = 0.049 s-1, Km = 48 microM. For the IMP dehydrogenation reaction: kcat = 0.25 s-1, Km [IMP] = 4.1 microM, Km [NAD] = 29 microM). Hydrolytic dehalogenation of 2-halo-IMPs without a requirement for NAD demonstrates the formation of a tetrahedral intermediate in the catalytic mechanism of IMP dehydrogenase.

Probing the active site of human IMP dehydrogenase using halogenated purine riboside 5'-monophosphates and covalent modification reagents

Active-site amino acid residues of human type II inosine 5'-monophosphate dehydrogenase (IMPDH) were investigated using the covalent modification reagents 6-chloroinosine 5'-monophosphate (6-Cl-IMP) and iodoacetamide. IMPDH was incubated with these reagents in the presence and absence of IMP, NAD, and NADH, and the activity of the enzyme for IMP dehydrogenation or 2-Cl-IMP dehalogenation was followed. IMPDH activity was rapidly lost when the enzyme was incubated with the IMP analog, 6-Cl-IMP, or with iodoacetamide. The enzyme was protected against inactivation in the presence of the substrate IMP. It was not protected against inactivation by NAD alone. Saturating concentrations of IMP and NADH reduced the inactivation rate by about the same amount as with IMP alone. IMPDH samples labeled with 6-Cl-IMP and an unlabeled control were alkylated with iodoacetamide, digested with trypsin, and analyzed by HPLC-mass spectrometry (HPLC-MS). All eight cysteines of human type II IMPDH were found to exist as free sulfhydryls on the active, unlabeled form of the enzyme. At an enzyme/inactivator ratio of 1:4, only one cysteine residue, Cys-331, was found to be covalently modified by 6-Cl-IMP. From the results of the substrate protection experiments and HPLC-MS data, it is concluded that 6-Cl-IMP binds in the IMP binding site of IMPDH and reacts covalently with Cys-331 to form a purine riboside 5'-monophosphate-enzyme adduct.

Efficacy and safety of radiofrequency catheter ablation for paroxysmal supraventricular tachycardias

From January 1992 to June 1993, 100 consecutive patients with clinically documented paroxysmal supraventricular tachycardias underwent radiofrequency catheter ablation. Group 1 consisted of 46 patients (male:female = 9:37, age: 46 +/- 13 years) with slow-fast atrioventricular nodal reentrant tachycardia. Radiofrequency current was aimed at the slow pathway area which was identified by both anatomical and electrophysiological methods. A mean application of 8 +/- 9 was delivered at a mean power of 22 +/- 4 watts with a mean duration of 21 +/- 3 seconds. Selective ablation of slow pathway conduction was achieved in 28 patients and modification of slow pathway conduction in 12 patients. Antegrade fast pathway conduction was ablated in 3 patients, and retrograde fast pathway conduction in 1. Mean peak CPK was 156 +/- 117 IU/L after ablation. Neither AV block nor clinical recurrence was found during 9.7 +/- 5.1 months follow up. Group 2 consisted of 54 patients with accessory pathway (AP) mediated atrioventricular reciprocating tachycardia. For 35 patients (M:F = 21:14, age: 40 +/- 12 years) who had left-sided accessory pathway, catheter ablation was approached by the retrograde trans-aortic technique in 33 patients and by the transseptal left atrial approach through patent foramen ovale in 2 patients. The mean energy delivered was 28 +/- 5 watts for a duration of 27 +/- 12 sec and 9 +/- 8 applications. The accessory pathway conduction was successfully ablated in 30 patients (86%). Mean peak CPK was 392 +/- 534 IU/L. Cardiac tamponade occurred in 1 patient and transient cerebral ischemia in another, but without mortality. No clinical recurrence was found during 9 +/- 4 months follow-up. Nineteen patients (M:F = 7:12, age: 36 +/- 11 years) had right-sided AP. The mean energy required for successful ablation was 30 +/- 4 watts for a duration of 35 +/- 15 sec and 12 +/- 9 applications. Mean peak CPK was 147 +/- 70 IU/L. Clinical recurrence occurred in 3 patients (15.8%), 1 of them had subsequent successive ablation. The overall immediate procedure success rate for right-sided AP was 65%. In conclusion, radiofrequency catheter ablation is a safe and effective treatment modality for patients with paroxysmal supraventricular tachycardias.

Establishment and characterization of differentiated, nontransformed hepatocyte cell lines derived from mice transgenic for transforming growth factor alpha

Hepatocytes are extensively used in studies of gene regulation but cannot be maintained in long-term culture as replicating, differentiated cells while remaining nontumorigenic. We have derived two hepatocyte lines from livers of transgenic mice overexpressing transforming growth factor alpha, a potent hepatocyte mitogen, which overcome these limitations. The transgenic hepatocytes were maintained for > or = 2 months in serum-supplemented primary culture and gave rise to cell lines, of which two (AML12 and AML14) have been cultured for > 1.5 years (> 80 passages). Both lines have typical hepatocyte features such as peroxisomes and bile canalicular-like structures, do not grow in soft agar, and are nontumorigenic in nude mice. Like normal hepatocytes, AML cells express high levels of mRNA for serum (albumin, alpha 1-antitrypsin, and transferrin) and gap junction (connexins 26 and 32) proteins, secrete albumin, and contain solely isozyme 5 of lactate dehydrogenase. After extensive passaging, AML12 cells continue to strongly coexpress hepatocyte connexin mRNAs but do not display nonparenchymal cell markers. Although mRNA levels for some serum proteins progressively fall, high expression in late AML12 cultures may be regained by passage in serum-free medium. The AML14 line loses expression of both differentiated markers and transgene mRNA with extended passaging, and hepatocytic traits are only partially restored by passage in serum-free medium. These differentiated, nontumorigenic cell lines should serve as models in which to study hepatocyte growth and differentiation.

Factors associated with viremia and elevated transaminase levels in asymptomatic hepatitis D virus-infected risk groups

To detect hepatitis D virus (HDV) RNA in asymptomatic HDV-infected risk groups, Northern blot hybridization was carried out using a strand-specific riboprobe. Univariate and multivariate analyses were carried out to evaluate factors associated with HDV viremia and elevated transaminase levels in these subjects. Two (15%) of 13 antibody to HDV (anti-HDV) -positive intravenous drug addicts, 15 (33%) of 45 anti-HDV positive prostitutes, and 6 (40%) of 15 anti-HDV positive brothel goers had detectable serum HDV RNA. Older age (> 31 years old) was negatively associated with HDV RNA (P < .04), while hepatitis B e antigen (HBeAg) was positively associated with it (P < .002) in univariate analysis. Only HBeAg was still significant in multivariate analysis (P < .05). Of the 76 asymptomatic anti-HDV positive case, 28 (37%) had mildly elevated serum ALT levels and only 5 (7%) had ALT levels more than twice normal (> 80 U/L). HBeAg (P < .05) and HDV RNA (P < .02) were two factors associated with ALT elevation in univariate analysis, and HDV RNA was the only significant factor in multivariate analysis (P < .005). In summary, active replication of HBV seemed to be of help for the assembly of HDV and viremia. However, active replication of HDV was associated mostly with mildly elevated ALT levels in these subjects. These cases may represent a particular group in the disease spectrum of HDV infection.

Characterization of human type I and type II IMP dehydrogenases

Human IMP dehydrogenase, a target for anticancer and immunosuppressive chemotherapy, exists as two isoforms, types I and II. Nonfusion sequences of each isoform were overexpressed in an IMP dehydrogenase-deficient strain of Escherichia coli and purified to homogeneity. Both recombinant isoforms were tetramers, which was in agreement with the subunit structure of the native mammalian enzyme. The results of initial velocity and product inhibition studies were consistent with an Ordered Bi Bi kinetic mechanism for both isoforms. Substrate affinities were similar for types I and II with Km values of 18 and 9.3 microM, respectively, for IMP, and 46 and 32 microM, respectively, for NAD.kcat values were 1.5 and 1.3 s-1 at 37 degrees C for types I and II, respectively. Xanthosine 5'-monophosphate and NADH inhibited the two isoforms with identical inhibition patterns and inhibition constants. Mycophenolic acid, however, inhibited the type II enzyme with a 4.8-fold lower K than the type I. Selective inhibitors of the inducible type II isoform may mitigate toxicity caused by inhibition of the constitutively expressed type I isoform.

Expression of E-cadherin in immature rat and mouse testis and in rat Sertoli cell cultures

Cadherins are Ca(2+)-dependent cell adhesion molecules that play essential roles in organogenesis. Northern blot analysis was used to determine the levels of epithelial (E)-, neural (N)-, and placental (P)-cadherin expression in developing rat testes from 1-, 2-, 3-, and 4-wk-old rats. Highest expression of all three cadherins occurred during the first two postnatal weeks, prior to the establishment of the blood-testis barrier. Transcripts of all three cadherins were also detected in RNA isolated from Sertoli cells cultured from 3-wk-old rat testes. Immunoblot analysis demonstrated levels of E- and P-cadherin protein in the testis and Sertoli cells that corresponded to the levels of their respective RNA transcripts. Immunohistochemical reactivity of E-cadherin in 8-day-old mouse testis was associated with germ cells situated basally in the seminiferous tubules. This report establishes the expression of E-cadherin in the testis and the simultaneous expression of E-, N-, and P-cadherin in both testis and Sertoli cell cultures.

[Anatomic study of parietal bone for use as bone graft material]

Anatomic parietal bone structures of 45 adult Chinese cadavers (90 sides) were investigated by measuring the burr holes. The results were as follows. The average thickness of parietal was 5.059 mm and showed an increase with age. In the senile group it was 1.3-1.9 mm thicker than that of the pubertal and middle age. The measurement revealed significant difference in various areas and the posterior and middle parts of the bone was thicker than that of the anterior part. The thickness of diploic layer decreased with age and even disappeared. The above findings may provide a basic data for taking bone graft from parietal bone in clinic.

Enterocyte expression of calbindin, calbindin mRNA and calcium transport increases in jejunal tissue during onset of egg production in the fowl (Gallus domesticus)

1. Quantitative measurements of calbindin mRNA, calbindin protein and calcium uptake have been made in sectioned intestinal villi to determine the location and cellular characteristics of their expression in immature, point of lay and laying chickens. 2. Trace amounts of calbindin mRNA were detected by in situ hybridization in enterocytes located around the crypt-villus junction in jejunal tissue taken from immature and point of lay chickens. Large amounts of calbindin mRNA were detected in upper crypt and all villus enterocytes in tissue taken from laying chickens. Maximal levels of calbindin mRNA occurred in the basal third of the villus in laying chickens. 3. No calbindin was detected immunocytochemically in tissue taken from immature and point of lay chickens. Large amounts of calbindin were expressed in tissue taken from laying chickens. Maximal expression of calbindin in this case occurred in villus tip enterocytes. 4. Rapid uptake of calcium by tissue taken from laying chickens was twice that found in immature and point of lay birds. Calcium uptake in tissue taken from laying hens was also shown by quantitative autoradiography to take place maximally in villus tip enterocytes. 5. Regulation of calbindin gene expression and the cellular characteristics of calcium transport in laying chickens are discussed in terms of an adaptive response taking place in birds undergoing a daily loss of egg shell calcium.

P-cadherin and E-cadherin are co-expressed in MDCK cells

The Madin-Darby canine kidney (MDCK) cell line is a valuable model of epithelial cell function and the role of E (epithelial)-cadherin in MDCK cell activity is well-appreciated. Northern and immunoblot analyses were used here to demonstrate that, in addition to E-cadherin, MDCK cell cultures also express P(placental)-cadherin. Immunocytochemistry was then used to compare the localization and detergent extractability of P- and E-cadherin. While both cadherins were found at areas of cell-cell contact, the relative ease with which P-cadherin could be extracted suggests a weaker anchorage to the actin cytoskeleton than has been demonstrated for E-cadherin, and may correspond to less permanent cell-cell interactions than those attributed to E-cadherin. The co-expression of different cadherins by MDCK cells has not been fully explored and may influence interpretations of MDCK cell function that previously considered only the activity of E-cadherin.

Reduced light sensitivity of the circadian clock in a hypopigmented mouse mutant

Pink-eyed dilution (p/p) is a recessive mutation in mice which results in reduced pigmentation of the retinal pigment epithelium, as well as alterations in visual pathways and function. We investigated whether this mutation also affects light information reaching the circadian clock. Entrainment to a 12 h light 12 h dark cycle and the free-running period in constant darkness were not affected by this mutation. Phase shifts in response to 1 h light pulses consisting of bright white light at either circadian time 16 or 24 also did not differ between mutant and wild-type C57BL/6J mice. However, when 5 min, 502 nm light pulses of 1.2 x 10(-1) microW/cm2 or 4 x 10(-2) microW/cm2 were given at circadian time 16, the mutant mice responded with significantly smaller phase shifts than the wild-type mice. When animals were transferred to constant light, the free-running period of wild-type mice was longer than that of mutant mice, a finding which is consistent with a sensitivity difference between mutant and wild-type mice. Horseradish peroxidase tracing of retinal innervation of the hypothalamic suprachiasmatic nuclei (SCN)--the location of a circadian pacemaker--revealed a reduced innervation of the SCN in mutant mice compared with wild-type mice. The total volume of the SCN, as determined by neutral red stain, was also reduced in mutant mice, although not to as great an extent as the retinal innervation. Taken together, these results indicate that while basic characteristics of circadian clock function are not altered by the pink-eyed dilution mutation, the sensitivity of the clock to light is reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Measuring lidocaine metabolite--monoethylglycinexylidide as a quantitative index of hepatic function in adults with chronic hepatitis and cirrhosis

Lidocaine is metabolized to form monoethylglycinexylidide (MEGX) via oxidative N-deethylation in the liver. To assess the clinical value of this lidocaine metabolite as a quantitative liver function test, we measured the serum MEGX concentration 15 min after intravenous administration of a single dose of lidocaine (1 mg/kg) in 24 adults with chronic hepatitis, 47 patients with cirrhosis and 26 normal controls. A fluorescence polarization immunoassay was used to obtain the MEGX value. The MEGX concentration in controls was 67 (54-95) ng/ml (median with 16th-84th percentile in parentheses), which was higher than 43 (23-61) ng/ml in patients with chronic hepatitis and 24 (7-52) ng/ml in those with cirrhosis (P < 0.05). In addition, the serum MEGX levels are proportional to the galactose elimination capacity, and inversely proportional to Pugh's score, the prothrombin time and indocyanine green retention ratio. If a MEGX concentration of below 54 ng/ml is taken as an indicator of hepatic dysfunction, its diagnostic sensitivity for hepatic disorder is 84.5%, specificity 88.5% and accuracy 85.6%. Furthermore, after a 10-month follow-up, patients with MEGX formation above 30 ng/ml had a higher survival rate than those with a MEGX concentration below this level (P = 0.004). In conclusion, the MEGX formation test reflects the severity of hepatic dysfunction quite well, making it valuable both in the quantitative evaluation of liver function and in the prognostic prediction of adults with liver diseases.

Hepatitis D virus infection among prostitutes in Taiwan

Two hundred and sixty-three adult licensed, 233 adult and 157 teenage unlicensed prostitutes from Taiwan were studied for prevalence and risk factors of hepatitis D virus (HDV) infection. The hepatitis B carrier rate among the three groups was 21, 15 and 20%, respectively, not significantly different from that of the general population in this area. However, the prevalence of HDV infection among carrier prostitutes was 55, 36 and 16%, respectively, much higher than that in general hepatitis B carriers. Univariate analysis revealed that the history of conducting paid sex for more than 12 months (P < 0.03), ear-piercing (P < 0.02), tattooing (P < 0.02), and gonorrhoea or syphilis (P < 0.005) were significant factors associated with HDV infection among these subjects. Multivariate analysis revealed that the history of ear-piercing and venereal diseases (P < 0.001) were still significant. In summary, genital ulcers caused by venereal diseases due to frequent sexual contact with multiple partners, and use of unsterilized needles in ear-piercing or tattooing play important roles in the high prevalence of HDV infection in prostitutes.

In vivo determination of the anisotropic diffusion of water and the T1 and T2 times in the rabbit lens by high-resolution magnetic resonance imaging

PURPOSE

Several magnetic resonance imaging (MRI) "tools" for ophthalmologic research have recently been developed in this laboratory, including improved gradient and radiofrequency coils and pulse sequences for high-resolution and diffusion imaging (100-microns resolution).

METHODS

These tools have been applied to the in vivo measurement of the relaxation parameters (T1 and T2) and the water diffusion coefficients (Dx and Dy) in the rabbit eye lens, both normal and cataractous. Maps of these parameters in the lens have been computer generated.

RESULTS

In the normal lens, water diffusion is highly anisotropic and tends to be parallel to the surface. In the trauma-induced cataractous lens, an increase in spin-spin relaxation times (T2) consistent with edema and alteration of diffusion patterns was observed in a study conducted 2 weeks postsurgery. A partial reversal was observed 6 weeks postsurgery. The histologic data on the enucleated lens at 6 weeks showed a loss of normal lens architecture. Images are shown that display other small structures of the anterior segment with great clarity.

CONCLUSIONS

An extension of this work, now underway, is the study of the formation of various types of cataract in animal models. It is hypothesized that these methods can be extended to humans as a quantitative alternative for the assessment of cataracts.

Hepatic actinomycosis with portal vein thrombosis mimicking hepatocellular carcinoma: a case report

A fatal case of hepatic actinomycosis with portal vein thrombosis is reported. The diagnosis of actinomycosis was delayed because of its rarity in Taiwan. This 63-year-old man was admitted due to body weight loss and poor appetite. No fever was noted before admission. Liver biochemical test showed a decreased serum albumin level with elevated serum levels of globulin and alkaline phosphatase. He was not a hepatitis B carrier and his serum level of alfafetoprotein was within normal range. Image studies (abdominal sonography and computed tomography) showed a hepatic mass over the medial segment of the left lobe with involvement of right lobe of the liver. Main portal vein thrombosis was also seen. Because of profound cachexia, he died of aspiration pneumonia and disseminated intravascular coagulation on the 11th day after admission. An autopsy revealed hepatic actinomycosis. High index of suspicion for early diagnosis and treatment is emphasized.

Ursodeoxycholic acid in the treatment of primary biliary cirrhosis: a short-term, randomized, double-blind controlled, cross-over study with long-term follow up

In order to evaluate the efficacy of ursodeoxycholic acid (UDCA) in the treatment of Chinese patients with primary biliary cirrhosis, a short-term, randomized, double-blind controlled, cross-over study was done with long-term follow up. In the first part of the study, 12 patients were randomly chosen to receive either UDCA 600 mg/day for 3 months followed by a placebo for 3 months or a placebo for 3 months followed by UDCA for 3 months. The clinical symptoms of pruritus improved when the patients were receiving UDCA but became worse when receiving a placebo. Mean serum levels of alkaline phosphatase (ALPase), gamma-glutamyl transferase (gamma-GT), total bilirubin, cholesterol, alanine aminotransferase (ALT) and aspartate aminotransferase all decreased below the baseline values when receiving UDCA treatment and all increased above the baseline values when receiving the placebo. The difference was statistically significant. In the second part of the study, 19 patients received long-term UDCA treatment (mean 20 months). The clinical symptoms of pruritus improved in 90% of the pruritic patients. Serum levels of ALPase, gamma-GT and ALT fell significantly from the pretreatment values, 6, 12 and from the mean 20 months after UDCA treatment. Serum levels of total bilirubin fell significantly 6 and 12 months after UDCA treatment but did not reach statistical significance at the last follow up. No patient lost antimitochondrial antibody and elevated immunoglobulin levels did not improve significantly, but the Mayo clinical risk score improved significantly after long-term UDCA treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Magnetic resonance and positron emission tomography imaging of the corpus callosum: size, shape and metabolic rate in unipolar depression

Magnetic resonance imaging (MRI) and positron emission tomography (PET) with fluorodeoxyglucose were used to study the size and shape of the corpus callosum in 20 patients with unipolar depressive disorder and 16 normal controls. An automated algorithm outlined the corpus callosum and divided it into quarters. The anterior and posterior quarters of the corpus callosum were larger in depressed patients than in controls, findings similar to most earlier MRI studies of the corpus callosum in schizophrenics. The patient-normal difference was more marked in females than in males. PET glucose metabolic values were higher in patients with thinner or smaller callosums. The presence of marked sex differences makes future larger studies controlling body size and age important.

Prevalence, infectivity, and risk factor analysis of hepatitis C virus infection in prostitutes

A population of 622 prostitutes in Taiwan was tested for antibodies to the hepatitis C virus (anti-HCV) using a synthetic peptide assay composed of representative determinants from capsid and nonstructural (NS) viral proteins. Seventy-four (12%) were positive and the remaining 548 (88%) were negative. Seventy-nine samples were retested by a second-generation anti-HCV assay composed of recombinant capsid and NS proteins of HCV. Both assays had a nearly perfect agreement (Kappa value = 0.91). Of the positive cases, 31% were positive for reactivity to capsid only. Most (60/74, 81%) of the cases positive for synthetic peptide assay were HCV RNA positive, indicating potential infectivity. On the basis of the results of synthetic peptide assay, univariate analysis showed that history of paid sex for longer than 6 months, blood transfusion, acupuncture, intravenous drug abuse, and age over 20 years were significant risk factors of HCV infection (P < 0.01). Elevated alanine aminotransferase levels (> 40 U/L) were positively associated with anti-HCV, while the presence of serum hepatitis B surface antigen was a negatively associated factor. Multivariate analysis revealed that history of paid sex for longer than 6 months and blood transfusion were positively associated with anti-HCV (P < 0.001). The latter only accounted for less than one fifth of the HCV-infected prostitutes. This study indicates strongly that sexual transmission is an important route for HCV infection in prostitutes. This risk group may spread HCV to other populations as a sexually transmitted disease.

Heterosexual transmission as the most common route of acute hepatitis B virus infection among adults in Taiwan--the importance of extending vaccination to susceptible adults

Sixty adult patients with acute viral hepatitis B (AVHB) and 93 controls were interviewed to assess potential risk factors of hepatitis B. Heterosexual contact was the only significant factor, and it was associated with 83% of cases. A history of having new sex partners or multiple sex partners within 6 months before the onset of AVHB or first sexual contact before 20 years of age were significantly associated with HBV infection (P < .005, respectively). There was a dose-response relationship between the number of sex partners and the risk of HBV infection. In multivariate analyses, a history of having new sex partners was the most important factor. Moreover, 18 of 24 sex partners of the patients were serum hepatitis B surface antigen- and HBV DNA-positive. Heterosexual contact is, therefore, the predominant route of HBV transmission among adults in Taiwan. Susceptible adults should receive vaccination.

Eyelid anatomy revisited. Dynamic high-resolution magnetic resonance images of Whitnall's ligament and upper eyelid structures with the use of a surface coil

We used a new radiofrequency surface coil and complementary software in eyelid magnetic resonance imaging. This custom-designed coil allows visualization of the eyelid structures in submillimeter resolution, providing detailed delineation of such structures as the orbital septum, levator aponeurosis, Müller's muscle, and orbital septa. The effect of Whitnall's ligament on the levator aponeurosis can be observed as a "tenting" of the aponeurosis; the change in vector force is persistent in upgaze and downgaze. This technology will allow accurate dynamic studies of eyelid anatomy in patients with various anatomically based eyelid diseases, before and after surgery, making it possible to test in vivo longstanding theories of normal and pathologic eyelid physiology.