Efficacy of image-enhanced endoscopy for colorectal adenoma detection: A multicenter, randomized trial

BACKGROUND

Improved adenoma detection at colonoscopy has decreased the risk of developing colorectal cancer. However, whether image-enhanced endoscopy (IEE) further improves the adenoma detection rate (ADR) is controversial.

AIM

To compare IEE with white-light imaging (WLI) endoscopy for the detection and identification of colorectal adenoma.

METHODS

This was a multicenter, randomized, controlled trial. Participants were enrolled between September 2019 to April 2021 from 4 hospital in China. Patients were randomly assigned to an IEE group with WLI on entry and IEE on withdrawal (n = 2113) or a WLI group with WLI on both entry and withdrawal (n = 2098). The primary outcome was the ADR. The secondary endpoints were the polyp detection rate (PDR), adenomas per colonoscopy, adenomas per positive colonoscopy, and factors related to adenoma detection.

RESULTS

A total of 4211 patients (966 adenomas) were included in the analysis (mean age, 56.7 years, 47.1% male). There were 2113 patients (508 adenomas) in the IEE group and 2098 patients (458 adenomas) in the WLI group. The ADR in two group were not significantly different [24.0% vs 21.8%, 1.10, 95% confidence interval (CI): 0.99-1.23, P = 0.09]. The PDR was higher with IEE group (41.7%) than with WLI group (36.1%, 1.16, 95%CI: 1.07-1.25, P = 0.01). Differences in mean withdrawal time (7.90 ± 3.42 min vs 7.85 ± 3.47 min, P = 0.30) and adenomas per colonoscopy (0.33 ± 0.68 vs 0.28 ± 0.62, P = 0.06) were not significant. Subgroup analysis found that with narrow-band imaging (NBI), between-group differences in the ADR, were not significant (23.7% vs 21.8%, 1.09, 95%CI: 0.97-1.22, P = 0.15), but were greater with linked color imaging (30.9% vs 21.8%, 1.42, 95%CI: 1.04-1.93, P = 0.04). the second-generation NBI (2G-NBI) had an advantage of ADR than both WLI and the first-generation NBI (27.0% vs 21.8%, P = 0.01; 27.0% vs 21.2.0%, P = 0.01).

CONCLUSION

This prospective study confirmed that, among Chinese, IEE didn’t increase the ADR compared with WLI, but 2G-NBI increase the ADR.

[A novel and simplified closure method for defect closure after endoscopic full-thickness resection of gastric submucosal tumors: short-term outcomes of "Shao-Mai" closure method]

Objective: To evaluate the feasibility and short-term efficacy of a novel and simplified closure method developed by our team for the defect closure after endoscopic full-thickness resection (EFTR) for gastric submucosal tumors (SMT) in the gastric wall. Methods: A prospective single-arm clinical study was used. Inclusion criteria: (1) the lesion was located in the fundus or the greater curvature of the stomach, and was confirmed to originate from the muscularis propria layer; (2) the diameter of the tumor was ≤3.5 cm, and the tumor had no extensive adhesion to the peritoneal tissues and organs in extraperitoneal cavity; (3) the tumor had no malignant features under ultrasound endoscopy; (4) the patient agreed to participate in the study; (5) patients with severe complications were excluded. Based on the above criteria, 20 patients with gastric SMT at the Endoscopy Center of Zhongshan Hospital of Fudan University from January 2015 to March 2018 were enrolled in this study, including 5 males and 15 females with mean age of 61.1 (38 to 70) years. Grasping forceps-assisted endo-loop snare ligation device which is called "Shao-Mai" method was used to close the defect site. All the patients underwent EFTR and "Shao-Mai" method to perform defect closure. After successful tumor resection by EFTR, an endo-loop was anchored onto the edge of the gastric defect with grasping forceps assistance and closed tightly. The observation indicators included tumor size, en bloc resection, operation time, postoperative complications and hospital stay. The follow-up indicators included tumor residual, local recurrence, and metachronous lesions. Results: All the 20 lesions were located in the muscularis propria with a size of 0.5-3.5 (mean 1.4) cm. Three of them were located in the greater curvature of the mid-upper gastric body, 17 were located in the fundus. The endoscopic "Shao-Mai" closure was successfully performed after EFTR in all the 20 cases. Endoscope was used uniquely through the entire process, without laparoscopic assistance. The operative time was 20-100 (mean 43.8) minutes, while the "Shao-Mai" closure procedure took a range of 3-30 (mean 10.1) minutes. The en bloc resection rate was 100%. The pathological diagnosis included 17 gastrointestinal stromal tumors and 3 leiomyomas. No major complications occurred during or after surgery. All the patients were discharged 1-11 (mean 3.1) days after operation. The wounds of all the cases were healed completely six months after operation and only scar was observed without ulcer. No residual lesion, tumor recurrence or metastasis, leakage or fistula of digestive tract were found during the follow-up period of 15-54 (median 41) months. Conclusion: The endoscopic "Shao-Mai" closure method is a simplified novel way, which is feasible, effective, and safe for closing the gastric defect after EFTR.

Influence of cyclophilin D protein expression level on endothelial cell oxidative damage resistance

We examined the influence of cyclophilin-D (CypD) protein expression level on endothelial cell oxidative damage resistance. A model of CypD protein expression or high expression in endothelial cells was established through gene silencing or cloning. The comparable groups were normal endothelial cells cultured in phosphate-buffered solution in liquid handling cells containing 500 mM H2O2 for 90 or 120 min, and then the medium was replaced with common nutrient solution and cultured again for 24 h. The apoptosis rate and nitric oxide (NO) levels of each group were tested. The cell apoptosis rate of the CyPD low expression group (32.51 ± 6.6 %) was significantly lower than that of the control group (52.57 ± 5.84%, P = 0.001), and total NO production was 24.06 ± 3 and 13.03 ± 3.55 μM. The apoptosis rate of the CyPD high expression group (24.24 + 3.08%) was significantly higher than that of the control group (7.7 + 0.68%, P < 0.001); total NO production was 3.55 ± 1.53 and 8.46 ± 0.77 μM, which was significantly different (P = 0.008). CypD protein could increase oxidative stress and cause endothelial cell injury and apoptosis.

First Report of Corynespora Leaf Spot of Eucalyptus in China

Eucalyptus is widely planted in the tropics and subtropics, and it has become an important cash crop in Southern China because of its fast-growing nature. In the Guangxi Province of southern China, Eucalyptus is produced on approximately 2 million ha, and two dominant asexual clones, Guanglin No. 9 (E. grandis × E. urophylla) and DH3229 (E. urophylla × E. grandis), are grown. Diseases are an increasing threat to Eucalyptus production in Guangxi since vast areas are monocultured with this plant. In June 2013, a leaf spot disease was observed in eight out of 14 regions in the province on a total of approximately 0.08 million ha of Eucalyptus. Initially, the lesions appeared as water-soaked dots on leaves, which then became circular or irregular shaped with central gray-brown necrotic lesions and dark red-brown margins. The size of leaf spots ranged between 1 and 3 mm in diameter. The main vein or small veins adjacent to the spots were dark. The lesions expanded rapidly during rainy days, producing reproductive structures. In severe cases, the spots coalesced and formed large irregular necrotic areas followed by defoliation. The causal fungus was isolated from diseased leaves. Briefly, the affected leaves were washed with running tap water, sterilized with 75% ethanol (30 s) and 0.1% mercuric dichloride (3 min), and then rinsed three times with sterilized water. Small segments (0.5 to 0.6 cm²) were cut from the leading edge of the lesions and plated on PDA. The plates were incubated at 25°C for 7 to 10 days. When mycelial growth and spores were observed, a single-spore culture was placed on PDA and grown in the dark at 25°C for 10 days. A pathogenicity test was done by spraying a conidial suspension (5 × 10⁵ conidia ml^-1) of isolated fungus onto 30 3-month-old leaves of Guanglin No. 9 seedlings. The plants were covered with plain plastic sheets for 7 days to keep the humidity high. Lesions similar to those observed in the forests were observed on the inoculated leaves 7 to 10 days after incubation. The same fungus was re-isolated. Leaves of control plants (sprayed with sterilized water) were disease free. Conidiophores of the fungus were straight to slightly curved, erect, unbranched, septate, and pale to light brown. Conidia were formed in chains or singly with 4 to 15 pseudosepta, which were oblong oval to cylindrical, subhyaline to pale olivaceous brown, straight to curved, 14.5 to 92.3 μm long, and 3.5 to 7.1 μm wide. The fungus was morphologically identified as Corynespora cassiicola (1). DNA of the isolate was extracted, and the internal transcribed spacer (ITS) region (which included ITS 1, 5.8S rDNA gene of rDNA, and ITS 2) was amplified with primers ITS5 and ITS4. 529 base pair (bp) of PCR product was obtained and sequenced. The sequence was compared by BLAST search to the GenBank database and showed 99% similarity to C. cassiicola (Accession No. JX087447). Our sequence was deposited into GenBank (KF669890). The biological characters of the fungus were tested. Its minimum and maximum growth temperatures on PDA were 7 and 37°C with an optimum range of 25 to 30°C. At 25°C in 100% humidity, 90% of conidia germinated after 20 h. The optimum pH for germination was 5 to 8, and the lethal temperature of conidia was 55°C. C. cassiicola has been reported causing leaf blight on Eucalyptus in India and Brazil (2,3) and causing leaf spot on Akebia trifoliate in Guangxi (4). This is the first report of this disease on Eucalyptus in China. References: (1) M. B. Ellis and P. Holliday. CMI Descriptions of Pathogenic Fungi and Bacteria, No. 303. Commonwealth Mycological Institute, Kew, Surrey, UK, 1971. (2) B. P. Reis, et al. New Dis. Rep. 29:7, 2014. (3) K. I. Wilson and L. R. Devi. Ind. Phytopathol. 19:393, 1966. (4) Y. F. Ye et al. Plant Dis. 97:1659, 2013.

Reduced tumorigenicity and drug resistance through the downregulation of octamer-binding protein 4 and Nanog transcriptional factor expression in human breast stem cells

Breast cancer is the most common type of malignancy among females. Previous studies examining breast cancer tissue have demonstrated the presence of stem cells, and have detected octamer‑binding protein 4 (Oct4) and Nanog transcription factor expression. In the present study, breast cancer stem cells (CSCs) were isolated and enriched from MDA‑MB‑231 breast cancer cell lines, and were defined as MDA‑MB‑231 stem cells using flow cytometry. The expression of Oct4 and Nanog in breast CSCs were detected by quantitative polymerase chain reaction and western blotting. RNA interference (RNAi) was used in order to downregulate the expression of Oct4 and Nanog. Drug resistance and tumor‑initiating capability following in vivo injection of MDA‑MB‑231 stem cells trans-duced with negative RNAi, Oct4 RNAi and Nanog RNAi were compared with that of MDA‑MB‑231 stem cells without siRNA transfection as a control group. In addition the capability of MDA‑MB‑231 breast cancer cells to initiate tumor formation in mice was compared with that of MDA‑MB‑231 stem cells. A paclitaxel inhibition test was also conducted in order to detect resistance of MDA‑MB‑231 breast cancer stem cells to this treatment. The MDA‑MB‑231 stem cells were revealed to exhibit elevated percentages of the cluster of differentiation (CD)44+CD24‑/low subset, high tumorigenicity and resistance to chemotherapy, all of which are characteristic stem cell properties. In addition, the MDA‑MB‑231 stem cells were more tumorigenic in vivo. Furthermore, the breast CSCs also expressed high levels of the Oct4 and Nanog transcription factors. Therefore, downregulation of Oct4 or Nanog expression may reduce chemotherapeutic drug resistance and tumorigenicity in breast CSCs. In conclusion, Oct4 and Nanog expression may be a key factor in the development of resistance to chemotherapy and tumor growth of breast CSCs. This finding indicates that Oct4 or Nanog‑targeted therapy may be a promising means of overcoming resistance to chemotherapy and inhibiting tumor growth in breast cancer treatment.

[The clinical significance of preoperative enteral immune nutrition in patients with malignant gastrointestinal tumors]

OBJECTIVE

To study the impact of preoperative enteral immune nutrition on patients with malignant gastrointestinal tumors.

METHODS

82 patients with malignant gastrointestinal tumors were divided equally into 2 groups:enteral nutrition group (EN) and normal diet group (Control). Enteral Nutritional Emulsion (TPF-T) served as nasogastically-fed liquid diet for the patients in EN group over a period of 7 days prior to surgery. Normal diet was given to the patients in control group under the same condition as those in EN group in terms of calories and nitrogen contents. Enzyme linked immunosorbent assay (ELISA) was performed to determine the quantity of serum albumin (ALB), transferrin protein (TRF), pre-albumin (PA) and retinol binding protein (RBP). Flow cytometry (FCM) was performed to determine T cell subsets. Postoperative complications, resumption of peristalsis, length of hospital stay, and nutritional costs were also recorded.

RESULTS

TRF, PA and RBP increased significantly in the patients in EN group compared with those in control group (P < 0.05). The patients in EN group had significantly higher proportions of CD3+, CD4+/CD8+ higher than those of control (P < 0.05). No serious complications (eg. death or gastrointestinal fistula) were found in the patients. The total nutritional cost for the patients in EN group was similar to that of the controls (P > 0.05). The patients in EN group had less postoperative complications, quicker resumption of peristalsis, shorter hospital stay and lower level of postoperative nutrition cost compared with those of controls (P < 0.05).

CONCLUSION

Enteral nutrition support can improve the nutritional status and immunity of patients with malignant gastrointestinal tumors, which has both pre-operative and post-operative benefits for the patients.

First Report of a Tospovirus in Mulberry

Mulberry (Morus alba L.) is an economically important crop grown widely throughout Asia. Various virus-like symptoms including mosaics, vein banding, and chlorotic ringspots have been observed and reported on mulberry trees in China and Japan for decades. However, the etiology of mulberry viral diseases is generally understudied, although two mulberry-infecting viruses, Mulberry latent virus (genus Carlavirus) (2) and Mulberry ringspot virus (genus Nepovirus) (3), have been partially characterized. In a recent (2010 to 2011) field survey in Guangxi Province, China, supported by the local government, the incidence of virus-like diseases of mulberry ranged between 40 and 80%. To identify the viruses infecting mulberry, deep sequencing of small RNAs (4) was conducted using an Illumina Genome Analyzer. Small RNAs were isolated from five samples of mulberry leaves showing various virus-like symptoms and sequenced. Among the contigs assembled, a 445-bp contig (GenBank Accession No. JX268597) was found to share 76.6% nucleotide identity and 83.0% amino acid identity to Groundnut bud necrosis virus (genus Tospovirus, family Bunyaviridae; Accession Nos. U42555 and AAC55521). To obtain a longer cDNA fragment of this virus, a reverse transcription (RT)-PCR was done with primers MV-N-F (5'-AAGCCATCAATGTGCCTCCGGA-3') and MV-N-R (5'-AACACCATGTCTACCGTCCGTC-3') that align to the S-RNA sequence encompassing the nucleocapsid (N) gene and a portion of the intergenic region (IGR) of the Tospovirus. PCR products of about 1,000 bp were successfully amplified from the total RNA of the three mulberry samples (sl-1, xcsy-1, and xcsy-4) showing vein banding symptoms, but not from asymptomatic mulberry (jk-1). These PCR products were cloned and sequenced. The lengths of the amplicons were 1,027 bp (isolate sl-1, JX173786), 987 bp (isolate xcsy-1, JX173787), and 979 bp (isolate xcsy-4, JX173788) and the partial IGRs of the sl-1, xcsy-1, and xcsy-4 isolates were 187 bp, 147 bp, and 139 bp, respectively. The coding regions for the N protein were 831 bp and the deduced proteins of 277 amino acid residues were 100% identical for all three isolates. Since the N protein of this virus shared up to only 74.4% identity to other tospoviruses (74.4% to Capsicum chlorosis virus, ABB83818; and 71.5% to Watermelon bud necrosis virus, ABY79095), it may represent a new member of the Tospovirus genus, temporarily named Mulberry vein banding virus (MuVBV), according to the species demarcation criteria for the Bunyaviridae (1). To the best of our knowledge, this is the first report of a Tospovirus infecting M. alba. In an RT-PCR screening of 48 randomly selected mulberry samples suspected to be virus-infected, 32 were MuVBV-positive. Giving the high incidence and the high yield loss associated with Tospovirus and the presence of thrips, suspected vectors for the virus, MuVBV may represent a substantial threat to the silkworm industry in China. References: (1) M. Q. K. Andrew et al. Virus Taxonomy: 9th Report of the ICTV. Elsevier Academic Press, San Diego, 2012. (2) T. Tsuchizaki. Annu. Phytopath. Soc. Japan 42:304, 1976. (3) T. Tsuchizaki et al. Annu. Phytopath. Soc. Japan 37:266, 1971. (4) Q. Wu et al. PNAS. 107:1606, 2010.

Bipolar plasmakinetic transurethral resection of the prostate vs. transurethral enucleation and resection of the prostate: pre- and postoperative comparisons of parameters used in assessing benign prostatic enlargement

INTRODUCTION

Transurethral enucleation and resection of the prostate (TUERP) may offer a better treatment for benign prostatic enlargement. We compared the perioperative parameters and outcome following bipolar plasmakinetic transurethral resection of the prostate (TURP) and TUERP.

METHODS

Data from two independent institutions were reviewed retrospectively. 50 and 45 consecutive patients were enrolled in the TURP and TUERP groups, respectively. Pre- and postoperative parameters, including prostatic specific antigen (PSA), prostate volume (PV), International Prostate Symptom Score (IPSS), quality of life (QOL) score, uroflowmetry and prostate volume (PV), were compared.

RESULTS

Age at surgery, preoperative PSA (5.8 +/- 4.0 versus 7.6 +/- 5.9 ng/ml) and PV (55.8 +/- 31.6 versus 53.2 +/- 26.8 g) showed no significant difference (p-value greater than 0.05). However, postoperative PSA (2.8 +/- 3.0 versus 0.8 +/- 0.4 ng/ml; p-value less than 0.05) and PV (15.2 +/- 7.7 versus 10.5 +/- 5.4 g; p-value less than 0.01) differed significantly between the TURP and TUERP groups, respectively. There were no significant differences in IPSS, QOL and Qmax between the two groups during follow-up (p-value is 0.62, 0.68 and 0.13, respectively). However, for the TUERP group, the postoperative post-void residual urine volume (PVR) was significantly better (13.8 +/- 19.5 versus 25.2 +/- 18.7 ml; p-value less than 0.01).

CONCLUSION

The TUERP technique achieved more complete resection than TURP, with a smaller post procedure PV and lower PSA and PVR after surgery. This may predict better long-term results for patients who had TUERP.

A Gal4-sigma 54 hybrid protein that functions as a potent activator of RNA polymerase II transcription in yeast

The bacterial final sigma(54) protein associates with core RNA polymerase to form a holoenzyme complex that renders cognate promoters enhancer-dependent. Although unusual in bacteria, enhancer-dependent transcription is the paradigm in eukaryotes. Here we report that a fragment of Escherichia coli final sigma(54) encompassing amino acid residues 29-177 functions as a potent transcriptional activator in yeast when fused to a Gal4 DNA binding domain. Activation by Gal4-final sigma(54) is TATA-dependent and requires the SAGA coactivator complex, suggesting that Gal4-final sigma(54) functions by a normal mechanism of transcriptional activation. Surprisingly, deletion of the AHC1 gene, which encodes a polypeptide unique to the ADA coactivator complex, stimulates Gal4-final sigma(54)-mediated activation and enhances the toxicity of Gal4-final sigma(54). Accordingly, the SAGA and ADA complexes, both of which include Gcn5 as their histone acetyltransferase subunit, exert opposite effects on transcriptional activation by Gal4-final sigma(54). Gal4-final sigma(54) activation and toxicity are also dependent upon specific final sigma(54) residues that are required for activator-responsive promoter melting by final sigma(54) in bacteria, implying that activation is a consequence of final sigma(54)-specific features rather than a structurally fortuitous polypeptide fragment. As such, Gal4-final sigma(54) represents a novel tool with the potential to provide insight into the mechanism by which natural activators function in eukaryotic cells.

A water-based triphenyltetrazolium chloride method for the evaluation of green plant tissue viability

A water-based 2,3,5-triphenyltetrazolium chloride (TTC) partitioning method using n-hexane for the evaluation of green plant tissue viability has been developed. Conventionally, the reduction of TTC to insoluble red-coloured triphenylformazan (TPF) has been used to detect seed, bud, leaf and cultured cell viability. However, the 95% ethanol used to extract TPF also extracts various pigments, such as chlorophyll, from plant tissues which interfere with the absorption of TPF at 485 nm. This new water-based method improves upon the current method by eliminating the interfering pigments in the hexane layer, and by minimising the non-enzymatic oxidation of the sample. When used to evaluate the tissue viability of chillstressed waxapple (Syzygium samarangense) plants, the refined method had a greater sensitivity than the electrolyte leakage method and thus provided a more precise assessment for the physiological state of various plant tissues.

The clinical use of small-dose tetracaine spinal anesthesia for transurethral prostatectomy

In a double-blinded study, we compared conventional dose tetracaine (8 mg), small-dose tetracaine (4 mg) with added fentanyl and epinephrine, and small-dose tetracaine (4 mg) with added fentanyl subarachnoid anesthesia. Forty-five patients scheduled for transurethral resection of prostate (TURP) under subarachnoid anesthesia were randomly assigned to Group 1 (8 mg hyperbaric tetracaine), Group 2 (4 mg hyperbaric tetracaine, 10 microg fen-tanyl, and 0.2 mg epinephrine), and Group 3 (4 mg hyperbaric tetracaine, 10 microg fentanyl, and 0.2 mL saline). Evaluations were performed after spinal anesthesia. Subarachnoid block was successful in all patients except one in Group 1, who required general anesthesia by mask. The median peak sensory levels 10 min after the induction of spinal anesthesia in Group 1 was T8, which was significantly higher than Group 2 and Group 3 (P < 0.05). The time of sensory and motor recovery in Group 3 was less than in Groups 1 and 2 (P < 0.05). Hypotension was observed in four patients in Group 1 and none in Groups 2 and 3. We conclude that small-dose 4-mg hyperbaric tetracaine plus 10 microg fentanyl might provide adequate anesthesia and fewer side effects for TURP when compared with the conventional (8 mg) dose.

IMPLICATIONS

Small-dose hyperbaric tetracaine (4 mg with 10 microg fentanyl added) may provide adequate anesthesia and fewer side effects for transurethral resection of the prostate.

Transglutaminase-3, an esophageal cancer-related gene

Transglutaminase-3 (TGase-3) is an enzyme with the ability to catalyze the irreversible cross-linking of peptide-bound glutamine residues either with peptide-bound lysines or with primary amines. It has been implicated in the formation and assembly of the cornified cell envelope of the epidermis, hair follicle and perhaps other stratified squamous epithelia. We show here the involvement of TGase-3 in human esophageal cancer. In an initial study, mRNA differential display was performed with 3 pairs of esophageal cancer tissues and matched normal adjacent mucosa by a 10-mer arbitrary primer and mixed anchored primers (GT15N, N = A, C and G). Four differentially expressed cDNA bands were consistently observed in all 3 normal tissues but barely detected in their tumor counterparts. One of them was identified to be the 3; end of TGase-3. Northern blot and dot blot analyses of 14 samples confirmed the down-regulation of TGase-3 in malignant tissues compared with normal epithelia. RT-PCR revealed that TGase-3 expression was lost in 3 esophageal carcinoma cell lines and decreased in 35/38 tumors compared with adjacent normal mucosa. Taken together, 49/52 (94.2%) esophageal tumors presented down-regulation of the gene. Our data suggest that alteration of TGase-3 expression is a common event in the development of human esophageal cancer.

Transglutaminase-3, an esophageal cancer-related gene

Transglutaminase-3 (TGase-3) is an enzyme with the ability to catalyze the irreversible cross-linking of peptide-bound glutamine residues either with peptide-bound lysines or with primary amines. It has been implicated in the formation and assembly of the cornified cell envelope of the epidermis, hair follicle and perhaps other stratified squamous epithelia. We show here the involvement of TGase-3 in human esophageal cancer. In an initial study, mRNA differential display was performed with 3 pairs of esophageal cancer tissues and matched normal adjacent mucosa by a 10-mer arbitrary primer and mixed anchored primers (GT15N, N = A, C and G). Four differentially expressed cDNA bands were consistently observed in all 3 normal tissues but barely detected in their tumor counterparts. One of them was identified to be the 3; end of TGase-3. Northern blot and dot blot analyses of 14 samples confirmed the down-regulation of TGase-3 in malignant tissues compared with normal epithelia. RT-PCR revealed that TGase-3 expression was lost in 3 esophageal carcinoma cell lines and decreased in 35/38 tumors compared with adjacent normal mucosa. Taken together, 49/52 (94.2%) esophageal tumors presented down-regulation of the gene. Our data suggest that alteration of TGase-3 expression is a common event in the development of human esophageal cancer.

Decreased expression of SPRR3 in Chinese human oesophageal cancer

cDNA fragments that were differentially expressed between human oesophageal carcinomas and matched normal adjacent mucosa were isolated using an improved mRNA differential display technique. One of them was identified as the 3'-untranslated region of SPRR3 and was homologous to the esophagin cDNA. Northern blot, dot blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses revealed that SPRR3 expression was lost in three cell lines of oesophageal carcinoma and was dramatically decreased in 54 out of 57 primary oesophageal carcinomas compared with adjacent normal mucosa. Esophagin has been shown to be down-regulated in western oesophageal carcinomas. The data suggest that esophagin is probably the protein product of the gene SPRR3 and that altered mRNA expression of SPRR3/esophagin is a frequent event in the development of Chinese oesophageal cancer.

Novel human esophagus-specific gene c1orf10: cDNA cloning, gene structure, and frequent loss of expression in esophageal cancer

We have identified a novel human gene, designated C1orf10, using modified differential display PCR. The C1orf10 gene, which spans 5 kb in length, is composed of three exons. The deduced protein contains 495 amino acids with one transmembrane domain. The amino acid sequence of C1orf10 is characterized by the presence of a calcium-binding motif of about 90 amino acids at its N-terminal and a conserved consecutive repeat sequence of 60 amino acids that was identified previously only in bacterial ice nucleation proteins. In normal adult tissues, C1orf10 is highly expressed only in the esophagus and was undetectable in a total of 15 other tissues examined, suggesting its important role in esophageal cells. The expression of C1orf10 is either dramatically reduced or absent in esophageal cancer cell lines (3/3) as well as primary esophageal cancer tissues (35/37) compared with the corresponding normal esophageal mucosa. Using a radiation hybrid panel, C1orf10 was found to be located on chromosome 1q21. These findings suggest that expression of C1orf10 is unique to esophageal cells and that loss of its expression may play a role in the development of esophageal cancer.

Home-based patient-controlled epidural analgesia with bupivacaine for patients with intractable herpetic neuralgia

This clinical report is based on retrospective observation of the outcome and effects of patient-controlled epidural analgesia (PCEA) with bupivacaine infusion administered at home to five patients with intractable herpetic neuralgia. All patients had severe pain (9 or 10 visual analogue scale [VAS]points) confined to the affected dermatomes, which was refractory to medication. The interval between zoster onset and PCEA application ranged from 27 to 60 days (mean, 37.2 d). The average daily amount of bupivacaine used was 36.5 to 91.2 mg (mean +/- standard deviation, 62.4 +/- 19.7 mg). The duration of PCEA therapy ranged from 10 to 28 days (18.4 +/- 7.6 d). One patient developed drug tolerance. All treatments resulted in effective and satisfactory pain relief (VAS, 0-3), with increase in physical activities to normal levels and easing of sleep and appetite impairment. No deleterious effects were found during PCEA therapy. After discontinuation of PCEA, two patients did not complain of pain but still had slight paresthesia, one of them required low-dose antidepressant for 17 days; three patients continued to have occasional sharp pain (VAS, 2-3) and required low-dose antidepressant and analgesic as-needed for one to six months. These results suggest that PCEA with bupivacaine infusion provides effective pain relief in patients with intractable herpetic neuralgia and is a feasible and effective home treatment modality with limited side effects.

Mutational analysis of yeast TFIIB. A functional relationship between Ssu72 and Sub1/Tsp1 defined by allele-specific interactions with TFIIB

TFIIB is an essential component of the RNA polymerase II core transcriptional machinery. Previous studies have defined TFIIB domains required for interaction with other transcription factors and for basal transcription in vitro. In the study reported here we investigated the TFIIB structural requirements for transcription initiation in vivo. A library of sua7 mutations encoding altered forms of yeast TFIIB was generated by error-prone polymerase chain reaction and screened for conditional growth defects. Twenty-two single amino acid replacements in TFIIB were defined and characterized. These replacements are distributed throughout the protein and occur primarily at phylogenetically conserved positions. Most replacements have little or no effect on the steady-state protein levels, implying that each affects TFIIB function rather than synthesis or stability. In contrast to the initial sua7 mutants, all replacements, with one exception, have no effect on start site selection, indicating that specific TFIIB structural defects affect transcriptional accuracy. This collection of sua7 alleles, including the initial sua7 alleles, was used to investigate the allele specificity of interactions between ssu72 and sub1, both of which were initially identified as either suppressors (SUB1 2mu) or enhancers (sub1Delta, ssu72-1) of sua7 mutations. We show that the interactions of ssu72-1 and sub1Delta with sua7 are allele specific; that the allele specificities of ssu72 and sub1 overlap; and that each of the sua7 alleles that interacts with ssu72 and sub1 affects the accuracy of transcription start site selection. These results demonstrate functional interactions among TFIIB, Ssu72, and Sub1 and suggest that these interactions play a role in the mechanism of start site selection by RNA polymerase II.

Miller-Dieker syndrome with microdeletion of chromosome 17p13.3: report of one case

Miller-Dieker syndrome (MDS) consists of lissencephaly, characteristic craniofacial appearance and sometimes other birth defects. Since 1983, it has been shown that most cases of MDS are caused by deletion of chromosome 17p13.3. Herein, we present a case of MDS in which the patient had characteristic craniofacial appearance in addition to lissencephaly. Although routine chromosome study showed a normal karyotype, deletion of chromosome 17p13.3 was suggested by high resolution GTG-banding and confirmed by FISH. About 36% of the cases reported by Dobyns had submicroscopic deletions of chromosome 17p13.3 in spite of normal karyotypes in routine chromosome studies. The high frequency of submicroscopic deletion in Dobyn's cases and our present case strongly suggests that chromosomal studies, including high-resolution banding and molecular genetic approaches such as FISH, are mandatory whenever MDS is suspected in cases of lissencephaly with normal karyotypes in routine chromosomal work-up.

[Clinical application study of intraoral high-level mandibular neurotomy: Reported of 19 cases]

Trigeminal neuralgia is a common disease in clinical practice. The recurrence rate after avulsion is relatively high. In order to reduce the recurrence rate, the author developed a new method and operated on 19 cases with intraoral high level trigeminal neurotomy based on 21 cases of adult human skull anatomy. The method is simple, safe and in good condition. The author emphasized that the proper management of the buccal branch during operation may have a close relation with the post-operative recurrence rate.

Determination of the food specific IgE antibodies: comparison of MAST-CLA and CAP systems

BACKGROUND

This study was carried out to compare two techniques used to determine the food specific IgE antibody.

METHODS

Thirty-four allergic patients were evaluated for most common food IgE antibodies by multiple allergosorbent chemiluminescent assay (MAST-CLA). IgE antibodies to eight of these food allergens were also measured by Pharmacia CAP (CAP) test.

RESULTS

The food specific IgE showed good agreement between MAST-CLA and CAP (kappa = 0.3-0.77). The sensitivity of MAST-CLA assay for food specific IgE antibody was variable comparing with that of CAP system. The accuracy ranged from 0.76 to 0.97. The agreement between the results of MAST-CLA and skin test was variable (kappa = 0.03-0.58). The agreement was poor in wheat, peanut and soybean (kappa = 0.03-0.12). Similar result between CAP and skin test was also obtained (kappa = 0.06-0.82). The agreement was poor in wheat (kappa = 0.06) and milk (kappa = 0.15).

CONCLUSIONS

Different results might be related to quality of the extract, how they are performed in vitro test and difference of correspondent allergens employed in the tests.

[A biomechanical investigation of Ha-coated ceramic implant]

Two samples of Ha-coated ceramic implants of which sintering temperatures were 850 degrees centigrade,1050 degrees centigrade respectively,were prepared.Pure titanium implant of the same size was accomplished using a transcortical implant model in adult Mongrel dogs.Follow-up periods were 1,3 and 6 months.The results in vivo were evaluated using push-out tests and scanning electron microscope.There were significant differences in push-coated ceramic implants and pure titanium implants,especially for the 1 and 3 months follow-up period.SEM investigation of the interface after push-out test showed for the HA-coated ceramic implants to be fractured in the coating layer and for the Ti-implant to be fractured at the implant-bone interface.

[An experimental study on the HA-coated zirconia ceramic material for an endosseous implant]

HA layer is sintered onto the surface of zirconia ceramic material.These column-like composite implants and titanium implants were inserted into the femurs of the dogs.The speciments were taken at the third month after operation,and the shear strengths between the implants and bone were measured.The undecalcified bone section containing the composite ceramic implant were cut for light microscopy,scanning electron microscopy and elemental analyses of C,P and Zr.Mechanical testing results revealed that the attachment strength of HA-coated zirconia samples is more stronger,as companied with the titanium samples.Histologic evaluations of the undecalcified specimens showed that extremely close juxlaposition of bone to HA-coated zirconia ceramic implants was seen.

[Three-dimensional computed tomography in the diagnosis of diseases of jaw bone(report of 22 cases).]

3DCT reconstruction,as a new roentnogenographic technique,has not been yet used so much in Oral Maxillofacial Surgery in our country.Scine early 1993,22 cases of 3DCT reconstruction have been performed on a Siemens Plus-s CT scanner for the diagnosis and surgical planning of jaw bone disease and injuries.It demonstrated that 3DCT reconstruction is a useful technique for the diagnosis and surgical planning of jaw bone disease.

Transport of 2-aminoisobutyric acid in cultured endothelial cells

Conflicting reports exist concerning the presence of a Na(+)-coupled amino acid transport system in cultured endothelial cells. We have employed a non-metabolizable analog, 2-aminoisobutyric acid (AIB), to investigate the activity of Na(+)-dependent amino acid transport in cultured human umbilical vein endothelial cells (HUVEC). We found a pronounced saturable, Na(+)-dependent component of AIB uptake in 'fresh' (non-starved) HUVEC. The Na(+)-dependent component accounted for 78% of total AIB uptake with a high sensitivity to external Na+. The accumulation of AIB was inhibited by ouabain preincubation, consistent with the energetics of Na(+)-coupled transport. Amiloride, an epithelial Na+ channel blocker, also inhibited AIB transport at high concentration. The results strongly support the presence of a Na(+)-coupled transport system of amino acid in HUVEC.

[Apolipoprotein B signal peptide insertion/deletion polymorphism in Chinese patients with coronary heart disease]

Insertion/deletion (Ins/Del) polymorphism of the apo B gene encoding signal peptide and its relation to coronary heart disease (CHD) and lipid trait were studied in 103 patients with CHD and 100 healthy individuals from Chinese Han nationality. The frequency of rare Del allele was 0.259, which was significantly lower than 0.34 in Caucasians (France), but higher than 0.16 in South Asian descents in UK. When the frequency distribution of the Ins/Del alleles was compared between CHD group and control group, the frequency of rare Del allele in the patient group was not apparently different from that in the control group (0.282 vs. 0.235, P > 0.05). As for the impact of the Ins/Del genotype on levels of lipid and apolipoprotein, the patients with at least one Del allele had significantly lower HDL-C level compared with those with only Ins allele in the CHD group (P < 0.01). Levels of other lipid parameters in each group were not obviously associated with the Ins/Del genotype. It is suggested that the Ins/Del polymorphism of the apo B signal peptide might be involved in lipid metabolism by an unidentified mechanism in some ethnic population. PCR is a useful method for distinguishing Ins/Del polymorphism of the apo B signal peptide.

Polymorphisms of apolipoprotein B gene in relation to coronary heart disease in Chinese Han nationality

Two polymorphic sites of apolipoprotein B (apoB) gene, XbaI and EcoRI, were examined in 80 patients with documented coronary heart disease (CHD) and 60 healthy individuals selected from a population of Chinese Han nationality. Allele frequencies at these sites were compared between the patients and controls and their impact on lipid metabolism was also investigated. The frequency of X+ allele (presence of XbaI cutting site) in CHD patients was 0.10, which was significantly higher than 0.01 in controls (P < 0.001). The same trend was detected for frequency of E-allele (lack of EcoRI cutting site) when it was compared between CHD patients and controls (0.11 vs 0.05), the difference was not statistically significant (P < 0.1, > 0.05). There was no relationship between XbaI RFLP and EcoRI RFLP. In the CHD patients, X+ allele was associated with the lower levels of HDL-C and apoAI when compared with X- allele, while no associations were found of X+ allele with other lipid parameters. On the contrary, the EcoRI polymorphism had no significant influence on plasma lipid and lipoprotein levels. Therefore, it was suggested that genetic variation at XbaI site of apoB gene might contribute to the determination of plasma HDL-C level and development of CHD in people among Chinese Han nationality.

[Comparison of food specific IgE antibody test (RAST) and skin tests in children with atopic dermatitis]

Thirty children with atopic dermatitis were enrolled in our study to evaluate the food specific IgE antibody assay (RAST) and skin tests as a screening test for food hypersensitivity. Our results showed that eight food antigens (fish, shrimp, crab, soybean, milk, egg-white, peanut, wheat) frequently elicited positive hypersensitivity reactions. Twenty-four patients had at least a positive skin reaction to one of the foods tested. Of the 240 skin tests, 30% (72/240) yield positive reactions. Eighteen patients had at least a positive RAST reaction to one of the foods tested, 20.9% (50/240) yield positive reaction. The agreement between skin test and RAST was 79.6%. Crab and shrimp accounted for most frequent positive reaction in both tests. The skin tests produced more positive results in skin testing than RAST, but gave a higher frequency of false positive results. The diagnosis of food allergy may be suspected from the medical history or by food specific IgE antibodies together with skin test as a screening test. Furthermore, the double blind placebo controlled food challenge should be considered as standard for clinical investigations.

[The diagnosis and the treatment on lingual thyroid]

Lingual thyroid is a rare example of ectopic thyroid.This paper reported three cases of lingual thyroid(all female,aged between 16 and 61 years) were discussed with diagnosis and treatment.A transoral excision using the median total glossotomy and precervical excision was performed through a transsuprahyoid approach.Postoperative complications is not developed.The approach above mention is better than that of median labiomandibular glossotomy.

[A comparative study of masticatory efficiency between partial denture wearers having one remaining tooth and complete denture wears]

Masticatory efficiency is one of the important indexes of judging masticatory function after dentures restored.The aim of this study was to measure and analyze masticatory efficiency of partial dentur wearers having one tooth left and complete denture wearers,by using a method of measuring msticatory crushed granules.The results showed that the crushed granules for partial denture wearers with one remaining tooth were smaller than that for complete ones.Therefore,partial dentures with a few remaining teeth were better than complete ones on effects.

[Metabolism of serum lipoprotein in hypothyroidism]

The changes of serum lipids concentrations in 15 patients with primary hypothyroidism were studied. 9 euthyroid persons in the similar age group with patients were selected as a control group. The serum levels of total and LDL cholesterol, TG, ApoAI, ApoB and ApoCII in patients before treatment were all higher than those of the control group. They decreased to normal level after treatment. The mean values of total cholesterol decreased from 6.7 mmol/L to 4.1 mmol/L, TG decreased from 2.5 mmol/L to 1.0 mmol/L, LDI-ch from 3.9 mmol/L to 2.4 mmol/L, ApoAI from 1.9 g/L, to 1.3g/L, ApoB from 1.2 g/L to 0.7 g/L and ApoCII decreased from 6.9 mg/dl to 3.9 mg/dl. There were no differences of HDI-ch level between patients before treatment and normal controls, HDI-ch level of patients only slightly decreased after treatment. Soon after the thyroid hormone treatment, all parameters of serum lipids, not including HDI-ch, were improved, as TT, level became normal, although the levels of TT4 was still not reached to normal level.

Radionuclide hysterosalpingography with technetium-99m-pertechnetate: application and radiation dose to the ovaries

Although radionuclide hysterosalpingography (RNHSG) has been suggested as an efficient procedure for assessing function of fallopian tubes, the radiation dose to the ovaries was addressed as an important issue to be taken into consideration. We describe a modified method of RNHSG, calculating the radiation dose to the ovaries. A small dose of approximately 18.5 MBq (0.5 mCi) of [99mTc]pertechnetate was administered directly into the uterine cavity without overpressure. The accuracy of the method was 84.5% as compared with the contrast hysterosalpingography. The estimated average dose to the ovaries was 0.057 mGy/MBq (0.21 rad/mCi) or 1.08 mGy (108 mrad) per study. RNHSG is an accurate method for functional study of fallopian tube patency with low radiation dose.

Femtosecond temporal encoding in barium titanate

We describe two-beam coupling and temporal encoding experiments in barium titanate. Volume gratings are created in the photorefractive material by 50-fs optical pulses. Information in the writing pulses may be encoded as spatially distributed volume gratings in the crystal. Femtosecond temporal waveform reconstruction is demonstrated.

Rotavirus gastroenteritis in children: a clinical study of 125 patients in Hsin-Tien area

During a 2-year period from January 1988 to December 1989, 125 patients (68 boys, 57 girls), aged 30 days to 9 years, were diagnosed as rotavirus gastroenteritis at this hospital. Diagnosis was made by identification of the rotavirus antigen in stool samples by latex agglutination assay. Ninety-nine (79.2%) of them were under 2 years of age. The seasonal peak in incidence was from January to March. The most common clinical characteristics were watery diarrhea (100%), followed by vomiting (68.8%), fever (68.0%), cough (42.4%), rhinorrhea (17.6%), convulsions (6.4%) and moderate to severe dehydration (1.6%). Fecal occult blood was positive in 4 patients and fecal leukocytes were positive in one patient. Stool cultures revealed concomitant infections with enteropathogenic Escherichia coli in 4 patients. Of the 106 patients who underwent serum electrolyte examinations, serum sodium concentrations ranged from 135-145 meq/L in 81.9% (86/106) and serum potassium concentrations ranged from 3.5-5.0 meq/L in 86.8% (92/106). Leukocyte counts greater than 15,000/mm3 were found in 10.8% (13/120) of the patients. All 125 patients recovered from the diarrheal illness on follow-up. Our results showed a different seasonal distribution of this disease from that of a previous observation between 1983-1984 in Taipei City and provides original clinical information on rotavirus gastroenteritis in children living in an area of Taipei County. Using the simple and rapid latex agglutination assay, we can make early diagnosis of rotavirus gastroenteritis. Thus, early treatment and early isolation of patients to prevent nosocomial infection among hospitalized patients is possible.

Long term and large-scale cultivation of human hepatoma Hep G2 cells in hollow fiber bioreactor

Long-term and large scale cultivation of an anchorage-dependent cell line using an industrial scale hollow fiber perfusion bioreactor is described. Hep G2 cells (a human hepatoma cell line) were cultivated in an Acusyst-P (Endotronic) with a total fiber surface area of 7.2 m2 6 x 1.2m2) to produce Hep G2 crude conditioned medium (CCM). Pretreatment of the cellulose acetate hollow fibers with collagen enhances the attachment of the anchorage-dependent cells. We have succeeded in growing the Hep G2 cells in an antibiotics- and serum-free IMDM medium, supplemented with 50 micrograms/ml of Hep G2 CCM protein at inoculation. The Hep G2 cells replicate and secrete CCM protein in quantities comparable to those produced in DMEM containing 10% fetal calf serum (FCS). The highest CCM protein productivity during the 80-day cultivation was 1.1 g/day with a total of 30 g of protein accumulated. Hep G2 CCM (20-40 micrograms protein/ml) was comparable to or even better than 10% FCS in supporting the growth of Molt-4 (a human T leukemia cell line) and FO (a mouse myeloma cell line) cells in vitro. The availability of this large amount of Hep G2 CCM will aid the further purification and characterization of growth factor(s) which could be used as serum substituents.

[Distribution of apoE phenotypes and frequencies of apoE alleles in Mongolian population]

Distribution of apoE3/3, E3/4 and E2/3 were 88.2%, 9.7% and 2.2%, respectively, in a Mongolian population. No apoE2/2, E2/4 or E4/4 phenotypes were found in this study. The population of apo E3/3 and frequency of epsilon 3 in this Mongolian population were significantly higher than those of Western populations and the Han nationality of China. The above results indicated that apoE phenotypes are closely related to lipid levels. The cholesterol levels of individuals with apoE3/3 phenotype were much lower than those of individuals with apoE2/3 (P less than 0.01) and higher than those of individuals with apoE3/4 (P less than 0.05). The levels of apoA-1 of individuals with apoE3/3 were much lower than those of individuals with apoE2/3 (P less than 0.01), but no difference was found between apoE3/3 and apoE3/4 phenotypes (P greater than 0.05).

[Large-scale production of monoclonal antibodies using hollow fiber bioreactor]

Development of large-scale monoclonal antibody production using industrial scale hollow fiber bioreactor is described. Hybridoma cell lines H505AC and A306AA were cultivated in the hollow fiber perfusion bioreactor with a total fiber surface area of 7.2 m2 (6 x 1.2 m2) to produce anti-hepatitis B surface antigen (anti-HBsAg) monoclonal antibody IgM and anti-alpha-fetal protein (anti-AFP) monoclonal antibody IgG. The highest anti-HBsAg IgM productivity obtained during 49 days cultivation of H505AC was 0.135 g/day and the total accumulated IgM was 1.90 g. Results from the cultivation of A306AA in the hollow fiber module for 23 days showed the highest anti-AFP IgG productivity and the total accumulated IgG were 0.672 g/day and 7.21 g, respectively.

Comparison of RNAs and polypeptides of infectious pancreatic necrosis virus isolates from eel and rainbow trout

Thirteen isolates of infectious pancreatic necrosis virus (IPNV) from eel and rainbow trout in Taiwan were compared with the selected serotypes AB, SP and VR-299 by PAGE analysis of their RNA genomes and early polypeptides. All the IPNV isolates from eels (1984 to 1986) from Lu Kang and Ping Tung, and from rainbow trout eggs and fry from Dan Sway (1985 to 1986) were most closely related to the AB serotype. However four rainbow trout isolates from Dan Sway (1984) had a similar RNA pattern to that of VR-299, whereas their early polypeptides were different, showing evidence of some mutations. Both RNA and polypeptide PAGE patterns were used to distinguish the isolates from known selected IPNV strains showing that this approach can be used for epizootiological studies.

[Plasma prostaglandins E, E2 and F2a in nasopharyngeal carcinoma (NPC)]

The levels of prostaglandins E, E2 and F2a (PGE, PGE2, PGF2a) in plasma of NPC patients, patients with other tumors and normal individuals were monitored by radioimmunoassay. The results showed that PGE and PGE2 levels in the plasma of NPC and other cancer patients were significantly higher but the PGF2a/PGE2 ratio was obviously lower than that of the normal (P less than 0.05). But there were not much changes in the PGF2a levels (P greater than 0.05). However, no difference was found between the PG8 levels of the NPC and the other cancer patients (P greater than 0.05). Neither were there any significant changes in the PGE2 and PGF2a plasma levels and ratio of PGF2a/PGE2 in 26 NPC patients staged according to TNM classification. It is indicated that there is a relation between PGE, PGE2 and nasopharyngeal carcinoma.

Rabbit apolipoprotein A-I mRNA and gene. Evidence that rabbit apolipoprotein A-I is synthesized in the intestine but not in the liver

In order to study the tissue-specific expression of rabbit apolipoprotein (apo) A-I, a 923-base-pair clone, pRBA-502, complementary to rabbit apo A-I mRNA was identified from a rabbit intestinal cDNA library by hybrid-select translation and immunoprecipitation methods. Northern blot and dot-blot hybridization, utilizing 32P-labeled pRBA-502, revealed that the rabbit apo A-I gene is expressed in the intestine, not in the liver and that rabbit apo A-I mRNA is about 950 nucleotides in length. The entire nucleotide sequence of pRBA-502 has been determined and the complete amino acid sequence of the corresponding apo A-I has been deduced. The mRNA codes for a protein comprising 265 amino acids. Amino acids 1-18 and 19-24 of the primary translation product represent the presegment and prosegment, respectively, of apo A-I. Matured rabbit apo A-I contains 241 amino acids and has a molecular mass of 27612 Da. Using pRBA-502 as a probe, a 15.5-kb genomic fragment, which contains the entire apo A-I gene, was isolated from a rabbit liver genomic library. Sequence analysis of the gene shows that the 200 base pairs of the 5' upstream flanking region of the rabbit and human apo A-I genes showed 78% sequence homology. Like the human apo A-I gene, the rabbit apo A-I gene is interrupted by three intervening sequences. Except for two nucleotides in the fourth exon, the coding sequence of the rabbit liver apo A-I gene is identical to that of pRBA-502. Our data showed that the lack of expression of apo A-I gene in rabbit liver is not due to the alternation of rabbit liver apo A-I gene sequence and suggest that the expression of apo A-I gene in rabbit liver is regulated by a trans-acting regulating element(s).

Isolation and characterization of a full-length rabbit apolipoprotein E cDNA

In order to study the primary structure of rabbit apolipoprotein (apo) E and the regulation of levels of liver apo E mRNA by dietary cholesterol, we have cloned and sequenced a full length rabbit apo E cDNA. DNA sequence analyses suggests that rabbit apo E is synthesized with an additional 18 amino acids as the prepeptide. The mature rabbit apo E contains 293 amino acids with a calculated molecular weight of 33,528. It has a 76% amino acid sequence homology with human apo E. Northern blot analyses showed that rabbit apo E mRNA is about 1200 nucleotides in length. Using mRNA dot blot analyses, we found that dietary cholesterol has no effect on the level of apo E mRNA in rabbit liver. We conclude that the elevated levels of plasma apo E in rabbits fed a cholesterol-rich diet is not a result of an increase of levels of apo E mRNA in the liver.