Color Doppler imaging study of retrobulbar hemodynamics in chronic angle-closure glaucoma

PURPOSE

To evaluate the retrobulbar hemodynamics in patients with chronic angle-closure glaucoma (CACG) by using color Doppler imaging (CDI) and to correlate the degree of glaucomatous visual field loss with the hemodynamic parameters.

DESIGN

Prospective case series.

PARTICIPANTS AND CONTROLS

Twenty-six Chinese patients with CACG and 26 age-matched and gender-matched normal subjects were recruited. All CACG patients had history of chronic intraocular pressure (IOP) elevation and asymmetric visual field defects between their fellow eyes. After receiving laser peripheral iridotomy and/or filtration surgery, all of them had bilateral medication-free controlled IOP before enrolling into the study.

METHODS

Each subject underwent CDI measurement in the central retinal artery (CRA) and the nasal and temporal short posterior ciliary arteries (PCA). Visual fields of the CACG patients were obtained with Humphrey 24-2 program. The visual field defects were scored with the Advanced Glaucoma Intervention Study (AGIS) system. For each CACG patient, the eye with lower AGIS score was defined as the better eye and the eye with higher score as the worse eye.

MAIN OUTCOME MEASURES

Peak-systolic velocity (PSV), end-diastolic velocity (EDV) and resistance index (RI) were determined.

RESULTS

The EDV in the CRA and the temporal PCA was decreased significantly (P = 0.041 and 0.023, respectively) in the worse eyes of CACG patients compared with those in the control eyes. The better eyes of CACG patients showed no significant change in hemodynamic parameters compared with the control eyes. While comparing the fellow eyes of CACG patients, the worse eyes had significantly lower EDV in the temporal PCA (P = 0.012) than the contralateral better eyes. In 11 CACG patients with a difference of at least 8 in AGIS visual field scores between their fellow eyes, the worse eyes had significantly lower EDV (P = 0.041) in the CRA and lower PSV (P = 0.018) and EDV (P = 0.018) in the temporal PCA compared with those in the contralateral eyes. In multivariate regression analysis, the AGIS scores were significantly correlated with the PSV in the CRA (P = 0.015) and with the EDV (P < 0.001) and RI (P = 0.027) in the temporal PCA in patients with CACG.

CONCLUSIONS

Patients with well-controlled CACG may have decreased retrobulbar blood flow velocities and increased vascular resistance in the CRA and temporal PCA. The degree of retrobulbar hemodynamic impairment was well correlated with the degree of glaucomatous visual field loss.

Unusual electrocardiographic manifestations in acute isolated right ventricular infarction

Electrocardiographic (ECG) manifestation of ST-segment elevation in the precordial leads during acute myocardial infarction is usually due to anterior myocardial infarction secondary to occlusion of the left coronary artery. Herein, we reported a rare case of isolated right ventricular infarction (RVI) in which the ECG mimicked that of acute anterior left ventricular infarction (LVI). A 64-year-old man had acute isolated RVI documented by positive cardiac enzymes and echocardiographic and angiographic findings. He developed hypotension. His ECG showed ST-segment elevation in the precordial leads V1 to V3 simulating that of acute anterior wall infarction. Coronary angiogram revealed total occlusion of the proximal right coronary artery with well-established collaterals from the left coronary artery to the posterior descending artery. This case report reminds us that the presence of diffuse ST-segment elevation in the precordial leads could be due to acute isolated RVI rather than acute anterior LVI. The differentiation of these two entities is important, as their therapies are quite different.

Amebic liver abscess and human immunodeficiency virus infection: a report of three cases

Invasive amebiasis rarely occurs in homosexual men and human immunodeficiency virus (HIV)-infected individuals and has not been regarded as a beacon for concomitant HIV infection. We encountered a bisexual man with a protracted course of amebic liver abscess and amebic colitis. In the presence of fever, generalized lymphadenopathy, and elevated serum aminotransferase levels, HIV infection was suspected and then confirmed by a de novo seroconversion of HIV antibody. Subsequently, we noted two consecutive patients with amebic liver abscess, also later found to be infected with HIV. The ameba obtained from these three cases was identified as Entamoeba histolytica by amplification of 16S ribosomal RNA by polymerase chain reaction and direct sequencing. This observation suggests that amebic liver abscess and colitis can be presentations for HIV infection in the Far East. Thus, the local patients with invasive amebiasis, especially those with a protracted course or with risk factors of HIV infection, should be tested for HIV.

Non-penetrating trabeculectomy for open angle glaucoma

BACKGROUND

Non-penetrating trabeculectomy is used as the surgical intervention for open angle glaucoma. It has advantage of creating gradual filtration through the thin trabeculo-Descemet membrane to reduce markedly the postoperative complications typical for penetrating operation. We described our experience of the non-penetrating trabeculectomy for open angle glaucoma.

METHODS

This is a retrospective study of 28 eyes of 28 patients with primary open glaucoma (POAG). Non-penetrating trabeculectomy was performed by one surgeon from July 1998 to March 2000. Examinations were performed preoperatively and postoperatively in 1 and 7 days and 1, 3, 6, 12 and 21 months.

RESULTS

The mean follow-up was 12.5 +/- 6.3 months (S.D.). The mean preoperative intraocular pressure (IOP) was 27.8 +/- 6.7 mmHg. The mean postoperative IOP was 11.5 +/- 6.2 mmHg in 1 day and 15.7 +/- 5.8 mmHg in 1 week, and it remained stable in the following 12 months. IOP of 71.3% (20/28) of the eyes could be controlled below or equal to 21 mmHg with no or only topical antiglaucoma medication. There were only few postoperative complications.

CONCLUSIONS

Non-penetrating trabeculectomy is efficient in controlling intraocular pressure of open angle glaucoma. No entering the anterior chamber diminishes the postoperative complications typical of the penetrating trabeculectomy.

Chylous ascites in acute pancreatitis during pregnancy: case report

Chylous ascites is a rare clinical manifestation characterized by ascitic chylomicrons resulting from mechanical obstruction of or leakage from the lymphatic channel. Chronic disorders, especially malignancies, account for most cases of chylous ascites. Acute chylous ascites is less common than the chronic form. We present a rare case of acute chylous ascites secondary to acute pancreatitis during the third trimester of pregnancy. This 24-year-old woman was referred to our emergency department because of severe epigastralgia for several days. Abdominal computed tomography revealed diffuse enlargement of the pancreas and peripancreatic exudation. Massive chylous ascites was found during emergent abdominal exploratory laparotomy. An emergent cesarean section was done because of fetal distress and there was no further accumulation of chyle. A pancreaticocutaneous fistula resulting from the cesarean section was treated successfully with a fistulectomy. In conclusion, chylous ascites is a rare complication of acute pancreatitis. Cesarean section may be helpful in terminating chylous accumulation in acute pancreatitis during the third trimester of pregnancy.

Reproducibility of visual activation during checkerboard stimulation in functional magnetic resonance imaging at 4 Tesla

PURPOSE

To investigate the reproducibility of visual activation by checkerboard stimulation, we used functional magnetic resonance imaging (fMRI) at 4 Tesla (T).

METHODS

Four subjects were studied with fMRI at 4 T during checkerboard visual stimulation. The functional images were realigned and spatially normalized to the standard brain. For each subject, statistical parametric maps were made for each study, and the reproducibility was determined based on the number of supra-threshold voxels (Z > 3.5, 4.5, and 5.5).

RESULTS

The mean ratio for the number of supra-threshold (Z > 4.5) voxels was 0.75, and the mean ratio for the overlapping voxels was 0.61. Restricting the region of interest within the posterior half of the brain improved reproducibility values at the low threshold (Z > 3.5), but did not improve the values at the higher thresholds.

CONCLUSIONS

Despite the fact that more than half of the supra-threshold voxels were found to be active for the repeated scans, visual activation with checkerboard stimulation seems to be less reproducible than that by flash stimulation.

Synthesis, structure and properties of 1,19-disubstituted tetradehydrocorrin cobalt complexes

1,19-Disubstituted tetradehydrocorrins have a ring structure that is closely related to the corrin ring found in vitamin B12. We herein report the isolation and full characterization of a Co(I)-TDHC species and X-ray crystal structures and full characterization of related Co(II) and Co(III) corrins as models for vitamin B12 complexes.

Androgen-receptor gene CAG repeats, plasma testosterone levels, and risk of hepatitis B-related hepatocellular carcinoma

BACKGROUND

Worldwide, hepatocellular carcinoma (HCC) is more prevalent in men than in women, suggesting that sex hormones and/or X-chromosome-linked genes may be involved in hepatocarcinogenesis. We investigated the association of a trinucleotide (CAG) repeat in the androgen receptor (AR) gene (located on the X chromosome) termed "AR-CAG repeats," levels of plasma testosterone, and the risk of HCC in Taiwanese men. Chronic hepatitis B virus (HBV) infection, which is associated with risk of HCC, is hyperendemic in Taiwan.

METHODS

We compared the number of AR-CAG repeats in 285 HBV carriers with HCC and in 349 HBV carriers without HCC. We also conducted a nested case--control study on participants in a cohort study. Blood was collected prospectively from 110 case patients and 239 control subjects and was used to determine the number of AR-CAG repeats and plasma testosterone level. All statistical tests were two-sided.

RESULTS

The overall odds ratio (OR) for HCC was 1.72 (95% confidence interval [CI] = 1.03--2.89) for HBV carriers with 20 or fewer AR-CAG repeats compared with those with more than 24 repeats. This association was observed only in patients with late-onset HCC (OR = 2.37; 95% CI = 1.28--4.38). In the nested case-control study, HBV carriers in the highest tertile of testosterone levels had a statistically significantly increased risk of HCC (OR = 2.06; 95% CI = 1.14--3.70) compared with those in the lowest tertile. Elevated testosterone was more strongly associated with early-onset (OR = 4.67; 95% CI = 1.41--15.38) than late-onset disease. HBV carriers with 20 or fewer AR-CAG repeats and higher testosterone levels had a fourfold increase in HCC risk compared with those with more than 24 repeats and testosterone levels in the lowest tertile.

CONCLUSIONS

Higher levels of androgen signaling, reflected by higher testosterone levels and 20 or fewer AR-CAG repeats, may be associated with an increased risk of HBV-related HCC in men.

Contralateral monocular dominance in anterior visual cortex confirmed by functional magnetic resonance imaging

PURPOSE

Although it is known that the damage to anterior striate cortex results in temporal peripheral visual field loss of the contralateral eye in patients with cerebral visual disturbance, the monocularity of anterior striate cortex has not been demonstrated in normal living humans. The aim of this study was to investigate whether this could be shown noninvasively using functional magnetic resonance imaging of the human visual cortex.

METHODS

Eleven normal volunteers were studied with functional magnetic resonance imaging during alternating monocular visual stimulation using a 1.5 Tesla scanner. The data were motion corrected and spatially normalized to the standard brain. The monocular activation of the visual cortex was compared with the activation by the other eye.

RESULTS

In the individual data analysis, contralateral eye dominance was always observed in the anterior striate cortex. In the group analysis from 11 subjects, the area with contralateral eye dominance was found in the most anterior part of primary visual cortex where the calcarine fissure merged with the parieto-occipital sulcus.

CONCLUSIONS

This study shows that the contralateral eye dominance of anterior striate cortex can be detected noninvasively with functional magnetic resonance imaging during monocular visual stimulation. The finding confirms that the anterior striate cortex, where the monocular temporal crescent is represented, is primarily monocular, but the fact that greatest density of retinal ganglion cells and photoreceptors is in the nasal hemiretina must also be taken into account when interpreting these results.

Interspousal transmission of TT virus: low efficiency and lack of apparent risk factors

BACKGROUND

The TT virus (TTV) is a newly identified human DNA virus and little is known about its non-parenteral transmission. The aim of the present study was to explore the prevalence of TTV infection in spouses of index cases and the related risk factors.

METHODS

Serum TTV-DNA was studied in spouses of 41 subjects with TT viremia. For couples in which both husband and wife had TT viremia, nucleotide sequences of the open reading frame-1 region were analyzed by phylogenetic tree constructions.

RESULTS

Three (7%) of 41 spouses were positive for TTV-DNA. No differences were noted between index patients with seropositive spouses and those without seropositive spouses with regard to clinical characteristics, including parenteral risk factors and exposure duration. Nucleotide sequence comparison and phylogenetic tree analysis of the viral genome in three TTV-infected couples revealed the isolates to be closely related in two, with a homology of 97 and 98%, respectively.

CONCLUSIONS

These results suggest that interspousal transmission of TTV does occur; however,the efficiency of transmission is low compared with hepatitis C virus and GB virus-C. There are no apparent risk factors for transmission between spouses and further studies are needed to clarify other modes of non-parenteral transmission.

Safety and efficacy of cefpirome in comparison with ceftazidime in Chinese patients with sepsis due to bacterial infections

BACKGROUND

The safety and efficacy of cefpirome (CPM), a fourth-generation cephalosporin, has not yet been studied in an Asian population.

METHODS

Sixty-nine adult Chinese patients with sepsis due to bacterial infections were enrolled in the study and randomly assigned to receive CPM (2 g i.v. every 12 h) or ceftazidime (2 g i.v. every 8 h).

RESULTS

Both groups were comparable in terms of demographic, clinical and microbiological features. The causative pathogen was Escherichia coli or Klebsiella pneumoniae in the majority of microbiologically documented cases. The rates of clinical response (94 vs. 94%) and bacteriological response (65 vs. 68%) were similar in both groups. Similar adverse events, including rashes, gastrointestinal upset and asymptomatic elevation of hepatic enzymes, occurred in a minority of patients in both groups. All events were self-limited after discontinuation of the drugs.

CONCLUSION

CPM is as safe and effective as ceftazidime in the treatment of sepsis due to bacterial infections in Chinese patients.

Familial risk of hepatocellular carcinoma among chronic hepatitis B carriers and their relatives

BACKGROUND

Familial predisposition as a risk factor for hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) carriers has not been thoroughly explored.

METHODS

The HCC risk associated with having parents and/or siblings with HCC was evaluated by use of a cohort study of 4808 male HBV carriers. A case-control family study was also conducted on data from first-degree relatives of 553 HBV carriers who had newly diagnosed HCC (case subjects) and 4684 HBV carriers without HCC (control subjects).

RESULTS

In the cohort study, HBV carriers with a family history of HCC had a multivariate-adjusted rate ratio for HCC of 2.41 (95% confidence interval [CI] = 1.47-3.95) compared with HBV carriers without a family history of HCC. For carriers with two or more affected relatives, the ratio increased to 5.55 (95% CI = 2.02-15.26). Cumulative HCC risk by age 70 years was 235.6 per 1000 (95% CI = 95. 3-375.9 per 1000) for HBV carriers with family history compared with 88.9 per 1000 (95% CI = 67.9-109.9 per 1000) for those without. In the case-control family study, first-degree relatives of case subjects were more likely to have HCC (age-sex-adjusted odds ratio [OR] = 2.57; 95% CI = 2.03-3.25) than first-degree relatives of control subjects. The excess risk of HCC among relatives was particularly evident in siblings (sisters-age-adjusted OR = 4.55 [95% CI = 2.22-9.31]; brothers-age-adjusted OR = 3.73 [95% CI = 2. 64-5.27]), but it was also observed in parents. The cumulative risk of HCC to age 80 years was 83.0 per 1000 among relatives of case subjects and 42.0 per 1000 among relatives of control subjects. Among relatives of case subjects, the cumulative risk of HCC was greater if the case subjects were diagnosed before age 50 years (two-sided P =.047). Liver cirrhosis was 2.29 (95% CI = 1.68-3.11) times more frequent in relatives of case subjects than in relatives of control subjects.

CONCLUSIONS

First-degree relatives of patients with HBV-related HCC appear to be at increased risk of HCC and should be considered in the formulation of HCC-screening programs.

Low incidence of hepatitis C virus transmission between spouses: a prospective study

BACKGROUND

Interspousal transmission of hepatitis C virus (HCV) has been documented; however, the annual risk of interspousal transmission remains unclear.

METHODS

A long-term prospective study to define the risk of interspousal transmission of HCV was conducted. One hundred and twelve index patients with chronic hepatitis C and their anti-HCV seronegative spouses were enrolled.

RESULTS

The mean follow-up period was 45.9 months. Antibodies to HCV (anti-HCV) and HCV-RNA were tested for in each seronegative spouse every year. Seroconversion of anti-HCV occurred in only one spouse, 2 years after enrollment, with a concomitant acute hepatitis. This subject and his spouse were infected with HCV genotype 1b. Nucleotide sequence comparison of the hypervariable region of their HCV genomes showed a homology of 98%. Further phylogenetic analysis suggested that they had virtually the same isolate. Accordingly, the annual risk of interspousal transmission of HCV infection was 0.23% per year.

CONCLUSIONS

These findings suggest a low incidence of interspousal transmission of HCV; however, the risk may be cumulative and such couples should be educated to avoid HCV infection from their spouses.

Expression pattern of (+)-delta-cadinene synthase genes and biosynthesis of sesquiterpene aldehydes in plants of Gossypium arboreum L

The cotton (+)-delta-cadinene synthase, a sesquiterpene cyclase, is encoded by a complex gene family which, based on homology, can be divided into two subfamilies: cad1-A and cad1-C. Southern blots revealed several members of the cad1-C subfamily, and a single member of the cad1-A subfamily, in the diploid Gossypium arboreum genome. One of the cad1-C genes, cad1-C3, was isolated from this species. According to reverse transcriptase-polymerase chain reaction, transcripts of both cad1-C and cad1-A genes appeared in roots from the second day post germination and in 1-d-old cotyledons, whereas the transcription levels were too low to be detected in the hypocotyls. Initially, sesquiterpene cyclase activities were found to be high in the seedlings, then dropped in aerial organs but increased in roots during development. Sesquiterpene aldehyde contents followed the same pattern. In fully developed plants, the transcripts of cad1-C were detected in stems, leaves and pericarps, as well as in the sepals and petals 3 d before anthesis, but not at the day of anthesis. In contrast, cad1-A transcripts were not detected in any of these aerial organs. The sesquiterpene aldehyde contents increased in petals but decreased in sepals after anthesis. Treatment of G. arboreum stems with a Verticillium dahliae elicitor-preparation activated cad1-A transcription, but a significant level of cad1-C transcripts was detected both before and after elicitation. In G. hirsutum cv. GL-5, a glandless cultivar, the cad1-C gene was activated by the same fungal elicitor, followed by the synthesis of the sesquiterpene cyclase, and accumulation of sesquiterpene aldehydes. The cad1 gene expression during development and in response to elicitation, as well as the spatial and temporal pattern of sesquiterpene biosynthesis, constitute a chemical defense machinery in cotton plants.

Effect of mitomycin C for combined trabeculectomy and phacoemulsification

BACKGROUND

To evaluate the efficacy and safety of intraoperative mitomycin C (MMC) for trabeculectomy combined with phacoemulsification (phacotrab) in patients with coexisting glaucoma and cataract.

METHODS

We retrospectively reviewed the charts of consecutive patients who underwent phacotrab from July, 1996, to March, 1998. The pre- and postoperative intraocular pressure (IOP), number of glaucoma medications, visual acuity (VA), and postoperative complications were compared among 22 patients (22 eyes) who received intraoperative MMC and 18 patients (18 eyes) who did not receive MMC, served as the control group. Data of age, gender, type of glaucoma, number of glaucoma medications, cup-to-disc ratio of the optic nerve and the extent of visual field defects were also evaluated. Kaplan-Meier survival analysis was used to compare the surgical success rates between two groups.

RESULTS

The mean IOP decreased from 16.1 +/- 4.2 mmHg to 10.94 +/- 3.6 mmHg in the MMC group, and from 18.7 +/- 6.9 mmHg to 14.6 +/- 1.9 mmHg in the control group at one year of follow-up. The mean postoperative IOPs were significantly lower in the MMC group than in the control group at one week, two weeks, and one, two, nine and 12 months. Postoperative mean VA log10 minimum angle of resolution (MAR) improved significantly in both groups. The mean number of medications decreased from 1.91 +/- 0.75 to 0.18 +/- 0.50 in the MMC group, and from 1.89 +/- 0.47 to 0.72 +/- 0.75 in the control group (p < 0.001 for both). The one-year complete success rate was significantly higher in the MMC group (p = 0.0038) than in the control group. No major complication was found throughout the study.

CONCLUSIONS

Intraoperative MMC in phacotrab may improve postoperative filtration with less dependence on glaucoma medication. No significant adverse effects were associated with MMC application.

Variations in ocular hemodynamics in patients with early and late glaucoma

PURPOSE

To determine the retrobulbar hemodynamics in glaucoma patients with different degrees of optic nerve damage.

METHODS

Color Doppler imaging was performed in 52 patients with controlled primary open angle glaucoma (POAG) and in 25 control subjects. Glaucomatous eyes were divided into early and late groups based on the perimetry findings. Peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive index of the central retinal artery (CRA) and posterior ciliary arteries (PCA) were evaluated.

RESULTS

Early glaucoma showed significantly decreased PSV in nasal PCA when compared with the normal. Late glaucoma showed significantly decreased PSV and EDV in the CRA and nasal PCA, and significantly decreased PSV in temporal PCA as compared with the control and early glaucoma. The resistive index of the CRA also increased significantly in late glaucoma.

CONCLUSION

Eyes with advanced glaucomatous optic neuropathy were associated with more marked alterations in retrobulbar circulation than eyes with less nerve damage.

Expression pattern of genes encoding farnesyl diphosphate synthase and sesquiterpene cyclase in cotton suspension-cultured cells treated with fungal elicitors

Cotton plants accumulate sesquiterpene aldehydes in pigment glands. The two enzymes farnesyl diphosphate synthase (FPS) and (+)-delta-cadinene synthase (CAD), a sesquiterpene cyclase, are involved in the biosynthesis of these secondary metabolites. A full-length cDNA (garfps) encoding FPS was isolated from Gossypium arboreum and identified by in vitro enzymatic assay of the garfps protein heterologously expressed in Escherichia coli. Treatment of G. arboreum suspension-cultured cells with an elicitor preparation obtained from the phytopathogenic fungus Verticillium dahliae dramatically induced transcription of both FPS and CAD, paralleling the accumulation of the sesquiterpene aldehydes in these cells. For G. australe, a wild species from Australia, the V. dahliae elicitor preparation also caused an induction of FPS but only a low rate of induction of CAD, apparently because of a constitutive expression of the sesquiterpene cyclase gene in suspension-cultured cells. Two transcripts and proteins of FPS were detected in the elicited G. australe cells; the smaller FPS seemed to be de novo synthesized after elicitation. Furthermore, G. australe-cultured cells accumulated the cadinene, instead of sesquiterpene aldehydes, indicating that the biosynthetic pathway leading to sesquiterpene aldehydes was absent or blocked after FPP cyclization.

Effects of latanoprost 50 micrograms/ml on Chinese patients with primary open-angle glaucoma and ocular hypertension

BACKGROUND

This study was designed to determine the efficacy and safety of latanoprost 50 micrograms/ml in Chinese patients with primary open-angle glaucoma (POAG) and ocular hypertension (OH).

METHODS

A 14-day randomized, double-masked, parallel-group study comparing topical latanoprost with placebo was followed by a 10-week, one-armed, open-labeled latanoprost treatment study. Intraocular pressure (IOP), visual function, ocular manifestations and miscellaneous adverse effects were evaluated at baseline, and days 1, 7, 14, 15, week 6 and week 12 visits.

RESULTS

Twenty-six eligible patients were enrolled in the study. The mean IOP was significantly reduced from baseline only in the latanoprost-treated eyes during the first study period (p = 0.003 on day 1; p = 0.004 on day 7; p < 0.001 on day 14). Meanwhile, the mean IOP was significantly lower in the latanoprost-treated eyes than that in the placebo-treated eyes (p = 0.03 on day 1; p = 0.001 on days 7 and 14). Eyes in both groups showed significantly reduced IOP at each visit of the secondary 10-week latanoprost treatment period, with a mean decrease of 6.12 mmHg. The IOP-lowering effect showed no diminution throughout the study course. Conjunctival hyperemia occurred in 16 of all patients who underwent latanoprost treatment and was the most frequent adverse effect observed. No patient withdrew from the study because of intolerable side-effects.

CONCLUSIONS

Topical latanoprost is effective in reducing IOP for patients with POAG and OH. The pressure-lowering effect lasts for at least 24 hours after 1 drop instillation and no drift of effect is noted during this 12-week study. Conjunctival hyperemia was the most common side-effect, which was mild in degree and recovered after discontinuation of the medication.

Characteristics of three homologous 202 genes (Ifi202a, Ifi202b, and Ifi202c) from the murine interferon-activatable gene 200 cluster

The Ifi202 gene is part of the interferon-activatable murine gene 200 cluster on chromosome 1. Ifi202 encodes the p202 protein whose overexpression is growth inhibitory and which can bind and inhibit the activity of numerous transcription factors including c-Jun, c-Fos, NF-kappaB, E2F-1, E2F-4, MyoD, and myogenin. We report here the exon-intron structure of Ifi202 and the discovery of Ifi202b and Ifi202c, close homologs of Ifi202 (whose designation we now change to Ifi202a). Ifi202a, b, and c were colocalized to chromosome 1 bands H4-H5 by fluorescence in situ hybridization. Ifi202b encodes p202b, which is interferon-inducible and differs from p202a in only 7 of 445 amino acids. 202b mRNA is constitutively expressed in tissues in which 202a mRNA is expressed. Ifi202c is apparently an unexpressed pseudogene. In murine embryonic fibroblasts (MEFs) from 129 mice, the level of 202b mRNA is approximately half that of 202a mRNA. We knocked out the Ifi202a gene from 129 mice. The expression of 202b mRNA, but not 202a mRNA, persisted in the knockout mice and their MEFs at the same level as in wildtype mice. However, in MEFs from the knockout mice, the constitutive and interferon-induced levels of p202b were approximately as high as the constitutive and the interferon-induced levels of p202a plus p202b, respectively, in MEFs from wildtype mice. These findings suggest dosage compensation at the posttranscriptional level. This might account for the apparent lack of phenotype of the knockout mice.

[Regulation of fungal elicitors on the cell growth and biosynthesis of saponin of Panax ginseng cell suspension culture]

Adding fungal elicitors to the Panax ginseng cell suspension cultures, the biosynthesis of saponin was obviously induced, the total productivity of saponin in cultures could increase more than 30% of the control. During elicitation, the accumulation patterns of saponin in suspension cultured cells were changed, the culture time for maximum biosynthesis of saponin was shortened 2-4 days comparing with that of the control, and about 80% of biosynthetic saponin in elicited cells was secreted into medium, meanwhile the uptake for sucrose in medium of cells was enhanced, and the disturbing of pH in medium was observed, which predicated that an ion exchange occurred between elicited cells and medium.