Epstein-Barr viral latency and cell immortalization as targets for antisense oligomers

The approach of using an antisense oligonucleotide to oppose the synthesis of a single selected viral gene product needed to maintain the EBV episome in non-virus-producing cells appears to be promising not only for possible cure of latent viral infection, but also for reversal of EBV-driven cell proliferation. It is also possible that targeting multiple latent viral genes might mount a synergistic effect that would prove to be more efficient at curing latent infection. However, further work is needed to identify the reasons for the variable results that are observed as well as to prove specificity of the inhibitory effects. Finally, we are also working on other assays and methods to screen compounds rapidly.

Microwave effects on input resistance and action potential firing of snail neurons

Excitable tissues have been reported to respond to weak microwave (MW) fields, possibly by nonlinear perturbation of a cellular process such as ion conduction across membranes. We sought effects of MW (continuous wave, 2.45 GHz, specific absorption rates 12.5 or 125 mW/g) on input resistances and action potential (AP) intervals of neurons in ganglia of snails (Helix aspersa), at 20.9 +/- 0.1 degrees C. At 12.5 mW/g, input resistance did not change during irradiation, but increased (p < 0.05) afterward. At 125 mW/g, input resistance during irradiation was lower than in unirradiated controls. Serial correlograms changed marginally more frequently in MW experiments than in controls, but the changes had no consistent pattern. The AP firing rate was affected by MW, but the direction was not consistent across cells. When AP generation was modeled as being due to a neuronal input current, MW did not affect its mean, standard deviation, or autocorrelation. Unlike MW, temperature changes caused neurons to respond robustly and reversibly. Threshold for changing input resistance was 0.63 degree C. The data suggest that MW may enhance degenerative effects such as metabolic rundown or loss of ion channel patency, but do not indicate a specific mechanism for MW interaction with neurons.

Canadian multicenter randomized clinical trial of chorion villus sampling and amniocentesis. chromosome mosaicism in CVS and amniocentesis samples

Data on 1040 chorionic villus and 969 amniotic fluid samples were collected from women studied in the Canadian Multicentre Randomized Clinical Trial of Chorion Villus Sampling and Amniocentesis. Cytogenetic results were obtained from 98.0 per cent of chorionic villus samples and from 99.9 per cent of amniotic fluid samples. Level I mosaicism (a single cell with an abnormal karyotype) occurred frequently in both chorionic villus and amniotic fluid samples and appeared to have no clinical significance. Level II mosaicism occurred in 0.9 per cent of CVS mesenchyme and 1.5 per cent of amniotic fluid cultures and in general was not perceived to be of sufficient concern to warrant cytogenetic follow-up studies. Level III mosaicism was reported in 18 CVS cases (15 cytotrophoblast, 1 mesenchyme, and 2 with both cell methods) and in one amniotic fluid case. In all cases but one (fetus with trisomy 18), level III mosaicism was confined to the placenta. Maternal cell contamination occurring with a frequency of 6.4 per cent in the mesenchyme analyses was a concern. This study supports the final report of the Canadian Multicentre Randomized Clinical Trial of Chorion Villus Sampling and Amniocentesis. Cytogenetic analysis of chorionic villus samples appears to be an acceptable alternative to the analysis of amniotic fluid samples. However, because of mosaicism and maternal cell contamination concerns, the examination of both cytotrophoblast preparations and mesenchyme cultures from chorionic villus samples is recommended.

Early CT findings of acute cerebral infarction in the middle cerebral artery territory

For an early and definitive diagnosis of acute cerebral infarction by computed tomography (CT), we retrospectively analyzed the initial CT findings of 14 patients with proven acute middle cerebral artery (MCA) infarction within 4 hours after stroke onset. The following results were obtained: (a) abnormal CT findings could be recognized quite early in 13 patients (92.9%), (b) the most common and earliest finding was loss of defination of the gray-white interface at the lateral margins of the insula. This sign was recognized in 12 patients (85.7%) and could be detected as early as 1 hour after stroke onset, (c) the next common finding was narrowing or blurring of the Sylvian fissure in 10 patients (71.4%) and could be detected 1.5 hours after stroke onset, (d) an obscured outline or partial disappearance of the lentiform nucleus was recognized in 7 patients (50%) and could be detected 1.5 hours after stroke onset, (e) effacement of the cerebral sulci was found in 6 patients (42.9%) and could be detected 2.5 hours after stroke onset, (f) increased density in MCA or its major branches was not seen in our patients.

[An animal model for colon cancer metastases to the lung and establishment of metastatic cancer cell line]

Death, in most colon cancer patients, is not caused by their primary tumors. Instead, metastasis is the major cause of morbidity and death. There are few appropriate animal models to investigate the complexity of the metastatic process. Therefore, the pathogenesis of the metastasis process is not clearly understood. We injected SW480 cells into the cecal wall of athymic nude mice to develop an animal model for colon cancer metastasis and to produce a metastasizing tumor. After metastatic foci formed in the murine lung, we established a metastatic cancer cell line, named CC-ML1, by in vitro primary culture. The characteristics of CC-ML1 were (1) a shorter doubling time; (2) a slightly higher metastatic rate and number of colonies; and (3) less morphological variation than those of SW480. Our research suggests that a higher metastatic potential may be found in CC-ML1 than in SW480 after the advanced cycles of the metastatic process. Thus, the primary animal model in this study may be useful in future studies of cells with a high metastatic potential in the pathogenesis of colon cancer metastases.

Brachial plexus neuropathy associated with scrub typhus: report of a case

We report on a 20-year-old man who had scrub typhus with the unusual neurologic complication of brachial plexus neuropathy. The clinical features of fever, headache, pneumonitis, eschar, high Weil-Felix OX-K agglutination and Rickettsia tsutsugamushi immunofluorescence titers confirmed the diagnosis of scrub typhus. Brachial plexus neuropathy was proven by an electrophysiologic examination. He had a nearly complete recovery after adequate medical treatment.

Relationship between vascular thermotolerance and intratumor pH

The changes in blood flow, intratumor pH, and clonogenicity of tumor cells after one and two heatings were studied in SCK tumors of A/J mice. When SCK tumors were heated at 42.5 degrees C for 1 hr, vascular thermotolerance promptly developed and peaked at 18 hr post-heating. The intratumor pH was 7.05 +/- 0.14 (mean +/- S.D.) in control SCK tumors of A/J mice, with a significant decrease (p less than or equal to 0.001) to 6.86 +/- 0.08 and 6.70 +/- 0.08 when heated for 1 hr at 43.5 degrees C and 44.5 degrees C, respectively. However, when the vascular thermotolerance was at its peak, heating at the same doses caused little change in the intratumor pH. When SCK tumors were heated for the first time at 44.5 degrees C for 1 hr and left in situ, the number of clonogenic cells significantly declined. Such a secondary cell death could be attributed to the deterioration of the intratumor environment ensuing from the vascular damage. When the tumor vessels were thermotolerant, however, virtually no secondary cell death occurred after heating.

Microwave sensing of physiological movement and volume change: a review

The ability non-invasively to detect and monitor the movement of tissues and organs from outside the body provides many worthwhile areas of potential biomedical applications. Several non-invasive microwave techniques for contact and remote sensing of circulatory and respiratory movements and volume changes have been developed. In general, these systems consist of a microwave generator, a sampling device, a transmitting-receiving antenna, a set of signal-conditioning and processing devices, and a display unit. They operate at continuous-wave frequencies between 1 and 35 GHz and make use of amplitude and phase information derived from the received signal. The average power density of energy radiated by present systems ranges from approximately 0.001-1.0 mW/cm2. These systems are capable of registering instantaneous changes in fluid volume, pressure pulse, heart rate, and respiration rate in contact with body surface or at distances greater than 30 m, or behind thick layers of non-conductive walls.

Unusual causes of obstructive jaundice in children: diagnosis on CT

Three cases are presented with unusual causes of obstructive jaundice diagnosed on abdominal CT in children under the age of 15 years. All the cases were initially examined by ultrasound which was inconclusive. CT studies were subsequently performed were diagnostic. These cases included hepatocellular carcinoma, a common bile duct web and duodenal hematoma. The first two cases were surgically confirmed, while the third case was proved by clinical follow-up.

Structure-activity relationship between (E)-5-(2-bromovinyl)- and 5-vinyl-1-beta-D-arabinofuranosyluracil (BV-araU, V-araU) in inhibition of Epstein-Barr virus replication

The structure-activity relationship between (E)-5-(2-bromovinyl)- and 5-vinyl-1-beta-D-arabinofuranosyluracil (BV-araU and V-araU) in inhibition of Epstein-Barr virus (EBV) was evaluated. Both V-araU and BV-araU effectively inhibited EBV replication in virus-producer P3HR-1(LS) cells, as determined by DNA-DNA hybridization. The 50% effective doses (ED50) for viral DNA replication were 0.005 and 0.3 microM for V-araU and BV-araU, respectively. The in vitro therapeutic index was 4000 for V-araU and 1300 for BV-araU. Synthesis of EBV-induced polypeptides with molecular weights of 145,000 (145, 140, 130, and 110 kDa) was significantly inhibited by both drugs. Only V-araU inhibited the synthesis of 85-, 55-, and 32-kDa polypeptides by approx. 50%. Kinetic analysis of inhibition and reversibility of EBV DNA replication after removal of the drugs indicated that BV-araU has a more prolonged inhibitory effect than V-araU. These results indicate that the substitution of H by Br in the 5-vinyl group results in marked reduction in anti-EBV activity while prolonging the drug effect and diminishing cytotoxicity.

Expression of the Epstein-Barr virus BamHI A fragment in nasopharyngeal carcinoma: evidence for a viral protein expressed in vivo

A family of mRNAs that are transcribed rightward through the BamHI A fragment have been detected in C15, a nasopharyngeal carcinoma (NPC) which has been passaged in nude mice. Northern (RNA) blot hybridizations indicate that these RNAs are also expressed in three other NPCs which have been established in nude mice and in an NPC obtained at biopsy. Moreover, hybridization in situ detected transcription from BamHI A in 12 NPCs and 1 Epstein-Barr virus (EBV)-containing carcinoma of the parotid gland. In each case, transcription was detected in all of the malignant epithelial cells. Transcription was not detected in two cases of EBV-positive lymphoma biopsies by in situ hybridization nor in latently infected EBV-positive lymphoblastoid cell lines by Northern blot hybridization. The consistent transcription of these sequences in latently infected epithelial malignancy but not in lymphoid cells suggests that this viral function is associated with latent EBV infection of epithelial cells. Sequence analysis of a cDNA synthesized from the C15 tumor, representing the 3' end of BamHI A messenger RNA, revealed an open reading frame (ORF). Translation of this ORF in vitro produced several peptides that were immunoprecipitated with antisera from patients with NPC. The detection of antibodies to the protein encoded by the ORF present in the BamHI A cDNA indicates that BamHI A encodes a protein which is expressed in vivo and is antigenic.

Inhibitory effects of acyclic nucleoside phosphonate analogs, including (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine, on Epstein-Barr virus replication

(S)-9-(3-Hydroxy-2-phosphonylmethoxypropyl)adenine [(S)-HPMPA], (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)-2,6-diaminopurine [(S)-HPMPDAP], cyclic (S)-HPMPA [(S)-cHPMPA], 9-(2-phosphonylmethoxyethoxyethyl)-2,6-diaminopurine (PMEDAP), and (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine [(S)-HPMPC] were examined for their inhibitory effects on Epstein-Barr virus (EBV) replication. The 50% effective concentrations for inhibition of viral DNA replication were 0.16, 0.03, 2.0, 1.5, and 0.08 microM for PMEDAP, (S)-HPMPC, (S)-HPMPDAP, (S)-cHPMPA, and (S)-HPMPA, respectively. The relative efficacies based on the in vitro therapeutic index was (S)-HPMPC (5,000) greater than PMEDAP (1,000) = (S)-HPMPA (1,000) greater than (S)-cHPMPA (136) greater than (S)-HPMPDAP (78). Certain ratios of combinations of (S)-HPMPC with 3'-azido-3'-deoxythymidine produced a synergistic inhibitory effect on EBV genome replication, but others exhibited an antagonistic effect. These results indicate that this series of acyclic nucleoside phosphonate analogs, and in particular (S)-HPMPC, are potent and selective anti-EBV agents in vitro.

Fournier's gangrene: experience of four cases

Fournier's gangrene is an acute gangrenous inflammation of the male genitalia. In an 18-month period, four patients with Fournier's gangrene were treated at our hospital. Their ages ranged from 39 to 74 years (average 55.2). The presenting symptoms and signs included pain, swelling and necrosis of the scrotum and perineum, fever and jaundice were also noted. Three patients with the predisposing factor of urinary tract infection or perianal abscess recovered after surgical debridement and antibiotics treatment. Their hospital stay ranged between 13 and 50 days. One patient with diabetes, presenting severe septic shock at arrival, died one day after debridement. From the experience of our cases and review of the literature, early surgical debridement and antibiotics are mandatory for the treatment of Fournier's gangrene.

[Lennox-Gastaut syndrome with band form heterotopia: a case report]

A 10-year-old girl with developmental delay, mental retardation and intractable seizures is reported. She manifested clinically as Lennox-Gastaut syndrome with unknown etiology before admission. Brain MRI revealed a band-like lesion over the bilateral subcortical region being later recognized as band-form heterotopia. This type of heterotopia may be overlooked easily due to its symmetrical distribution and mild degree of cortical convolutional anomaly. As it is often associated with intractable seizures and psychomotor retardation, the prognosis is poor. This patient responded poor to ketogenic diet and anticonvulsants. We present this case and review the related articles.

An animal model for colon cancer metastatic cell line with enhanced metastasizing ability. Establishment and characterization

We have developed an animal model for colon cancer metastasis and produced a metastasizing tumor after using a microinjection technique to inject SW480 cells into the cecal wall of athymic nude mice during "minilaparotomy." After the metastatic foci formed in murine lung, an in vitro primary culture was performed and a new metastatic cancer cell line, which was designated as CC-ML3, was established. The studies included: 1) the comparison between SW 480 and CC-ML3 in morphology, growth kinetics, seeding and plating efficiency, and karyotype; and 2) carcino-embryonic antigen determination, origination, and metastatic ability of CC-ML3. The results showed that CC-ML3 was significantly different from SW480 in vitro and possessed a high metastatic potential in vivo. This newly developed animal model may thus be useful for studying the biology and pathogenesis of metastasis of human colonic cancer.

Human papillomavirus type-related DNA and c-myc oncogene alterations in colon cancer cell lines

Although squamous-cell epithelium is the most frequent target site of human papillomavirus (HPV) infection, a similar infection is demonstrated in columnar epithelial cells in this paper. The papillomavirus expression in three cell lines was detected in colorectal adenocarcinoma of Chinese patients. The HPV-16 and HPV-18 DNA sequences were found in colorectal cancer cell lines, which might suggest the correlation of HPV to the etiology of colorectal cancers. In addition, c-myc oncogene was identified by amplification in all three colorectal cancer cell lines, but only normal germ-line fragments were found in control tissue. The correlation between HPV and c-myc, and the implications of these findings in colorectal cancers are also discussed.

Identification and functional characterization of Epstein-Barr virus DNA polymerase by in vitro transcription-translation of a cloned gene

In order to identify the gene encoding the Epstein-Barr virus (EBV) DNA polymerase, a portion of the BamHI-A fragment containing the fifth leftward open reading frame (BALF5) of the EBV genome was cloned into SP6 and T7 promoter-containing vectors for in vitro transcription-translation. The RNA synthesized in vitro was used to program rabbit reticulocyte lysates, which were analyzed for the synthesis of the putative polymerase polypeptide (110 kDa) and assayed directly for EBV DNA polymerase activity. The polypeptide synthesized by the full-length BALF5 genomic fragment had a molecular mass of 110 kDa. 5'-truncated BALF5 with the first and second ATGs deleted produced 95- and 83-kDa polypeptides, respectively. All three translation products were enzymatically active and displayed resistance to high salt concentrations. The identity of the largest polypeptide as the viral polymerase was established by (i) immunoprecipitation with EBV-positive sera from patients with nasopharyngeal carcinoma and by a rabbit polyclonal antiserum prepared with a synthetic peptide derived from the DNA sequence of BALF5; (ii) identification of a polypeptide of identical size (110 kDa) immunoprecipitated from superinfected Raji cell extracts by these antibodies; and (iii) salt-resistant enzymatic activity which was neutralized by the rabbit EBV antiserum. Thus, BALF5 encodes a functional polymerase identical to that induced in superinfected Raji cells.

Renal osteodystrophy

The term "renal osteodystrophy" is used to include skeletal disorders of patients with chronic renal failure: osteitis fibrosa, osteomalacia, osteosclerosis, osteoporosis and the frequently associated extraskeletal calcifications. It is the chronic glomerular disease with phosphate retention and resultant hyperphosphatemia on one hand and deficient 1,25 (OH)2 D3 and resultant hypocalcemia on the other to induce secondary hyperparathyroidism. The three most common causes of chronic renal failure in our patients are chronic glomerulonephritis, diabetic nephropathy, hypertensive nephropathy in decreasing frequency, polycystic renal disease occurs in five patients. Other miscellaneous causes include nephrotic syndrome, chronic pyelonephritis, systemic lupus erythematosus, periarteritis nodosa, interstitial nephritis and renal stones. The bone changes are similar in primary and secondary hyperparathyroidism and the incidence of brown tumor is about 3% in the former and 1.5 to 1.7% in the latter. We present one among the 94 dialyzed patients who has long-standing severe chronic renal failure from polycystic kidney disease and develops brown tumor in the mid ulna after 7 years on maintenance hemodialysis. The incidence of brown tumor in our series is about 1.1%. Because of increased longevity of the dialyzed patients, brown tumor from secondary hyperparathyroidism is now more commonly observed. Hyperphosphatemia with serum calcium-phosphate products exceeding plasma solubility of 60 to 75 mg/dl may induce soft tissue and vascular calcification. This explains the much higher incidence of soft tissue calcification in secondary than primary hyperparathyroidism; two of our patients with generalized Monckeberg's type arterial calcification and multiple periarticular calcifications in five patients have been observed.(ABSTRACT TRUNCATED AT 250 WORDS)