Adsorption of hepatitis C virus particles onto the dialyzer membrane

It was recently found that the blood level of hepatitis C virus (HCV) RNA is significantly reduced after each dialysis procedure in patients on chronic hemodialysis. This study was designed to elucidate the mechanism for this phenomenon. In two patients with high serum levels of HCV RNA, the filtrate through the dialyzer (TF-alpha, Teijin Co., Tokyo, Japan) was analyzed for viral RNA using the polymerase chain reaction. At the end of dialysis, the filter was washed with saline, and during the saline washing, aliquots were taken for quantification of RNA by the branched DNA method. The HCV core antigen was quantified as a measure of viral particles, and hemoglobin was also measured for correcting for blood contamination. After the clearance of the blood, the filter was washed with guanidinium isothiocyanate, and the recovery of RNA was measured. The filtrate did not contain detectable RNA. The saline washing of the filter after dialysis contained a significant amount of RNA. Washing with guanidinium isothiocyanate of the thoroughly saline washed filter also recovered a significant amount of RNA. During saline washing, the recovery of RNA in the washing was much delayed behind that of hemoglobin, suggesting the adsorption of the former onto the filter membrane. There was a discordant recovery of RNA and HCV core antigen in the washing, the recovery of the former being delayed behind that of the latter. These results indicate that viral particles are adsorbed onto the inner surface of the filter membrane during dialysis. Some of these adsorbed viral particles are perhaps destroyed by hydraulic pressure applied to blood for dialysis.

Antibiotic MICs and short time-killing against Helicobacter pylori: therapeutic potential of kanamycin

We compared the susceptibility of Helicobacter pylori to several antibiotics, expressed as MICs and as bactericidal effectiveness in short (3 h) time-killing studies. Of the antimicrobial agent tests, clarithromycin and amoxycillin had the lowest MIC50, 0.063 and 0.125 mg/L respectively, for 24 strains of H. pylori. Minocycline, levofloxacin and lansoprazole followed, with MIC50s of 0.5, 1, and 2 mg/L, respectively. Three-hour time-killing studies using a standard strain demonstrated a different pattern. At 4 x MIC, kanamycin, metronidazole and clarithromycin produced 4.4, 2.6 and 2.1 log decreases in viability, whereas the remaining seven antibiotics (including amoxycillin) were less bactericidal. Amoxycillin's lack of bactericidal activity during brief incubations was confirmed by examining several different clinically isolated H. pylori strains. Clarithromycin's effect, on the other hand, was strain- and concentration-dependent. Kanamycin was the most potent antibiotic in short time-killing studies, with concentrations of 1 x MIC and 4 x MIC producing a reduction of more than 2 and 4 log respectively in all ten strains. Our data suggest that the MIC of antimicrobial agents against H. pylori does not necessarily predict their activity in short time-killing studies. Furthermore, our short time-kill data suggest kanamycin as a potential therapeutic choice for H. pylori infection, even though this agent's MIC would suggest limited activity.

Characterization of a nuclear factor that enhances DNA binding activity of SSCRE-BP/PUR alpha, a single-stranded DNA binding protein

Pur alpha has been identified as a single-stranded DNA binding protein that specifically binds to the purine-rich strand present in the DNA replication initiation zone of the human c-myc gene. We have previously demonstrated that chronic morphine treatment decreases the DNA binding activity of ssCRE-BP (single-stranded cyclic AMP response element-binding protein), which has been shown to be identical to pur alpha by cDNA cloning, and is abundant in the brain. In this report we identified an activator of ssCRE-BP/pur alpha in the brain and characterized it. Although purified ssCRE-BP/pur alpha or its GST-fusion protein exhibited very low DNA binding activities, they were markedly enhanced by including nuclear extract in the binding assay. The enhanced binding activity is trypsin-sensitive, heat-stable and has a molecular weight of approximately 66 kDa. Casein could substitute for the activator and increased the DNA binding activity of ssCRE-BP/pur alpha by one order. A series of deletion mutants were prepared in order to determine the DNA binding and activator interacting domains, and both of them were found to reside in AA 50-215 of ssCRE-BP/pur alpha. These data suggest that the DNA binding activity of ssCRE-BP/pur alpha is augmented by a nuclear protein, which may modulate the ssCRE-BP/pur alpha activity to develop morphine dependence and tolerance.

[A case of primary anterior mediastinal liposarcoma with a heterotopic mass in the pericardium of the same histology]

We experienced a case of primary anterior mediastinal liposarcoma with a heterotopic mass in the pericardium of same histology. Twenty reported cases in Japan were also studied. The patient was a 50-year-old male who visited the hospital because of an abnormal shadow on a chest X-ray. The diagnosis of anterior mediastinal tumor was confirmed by a chest CT. The patient underwent a complete resection of the mediastinal and intrapericardial masses. The histologic diagnosis was a well differentiated liposarcoma of Enzinger's classification. No evidence of recurrence or metastasis was detected in the third postoperative year. Liposarcoma is rarely seen in the mediastinum. Since radiotherapy and chemotherapy are ineffective therapeutic modalities, surgery would be the treatment of choice and complete surgical resection is mandatory.

Involvement of a single-stranded DNA binding protein, ssCRE-BP/Pur alpha, in morphine dependence

We have purified a nuclear protein from mouse cerebella that binds to single-stranded oligo-DNA of cAMP response element and is modulated by morphine treatment. Isolation of the cDNA clone showed that the nuclear protein (ssCRE-BP) was identical to Pur alpha, a DNA binding protein for single-stranded purine-rich sequences that was originally isolated as a replication factor. ssCRE-BP/Pur alpha and mRNA were abundant in the brain. The levels of ssCRE-BP/Pur alpha and the transcript were not changed by chronic morphine treatment, however, the levels of an activator of ssCRE-BP/Pur alpha, which is necessary for the DNA binding, may be modulated by the treatment.

MEKA/phosducin attenuates hydrophobicity of transducin beta gamma subunits without binding to farnesyl moiety

Hydrophobic modifications of transducin (T) gamma, such as farnesyl-and carboxyl-methylation, are essential for the association of T beta gamma with the photoreceptor disc membrane, and MEKA/phosducin is known to inhibit the association. In this study, we examined the effect of MEKA on the hydrophobicity of T beta gamma. MEKA could bind to T beta gamma without farnesyl/carboxyl-methyl moieties as well as native T beta gamma. In the Triton X-114 phase separation assay, T beta gamma-MEKA complex was recovered in the aqueous phase, whereas T beta gamma was recover in the detergent phase. N-terminal portion of MEKA which includes T beta gamma-binding domain was not sufficient to reduce the hydrophobicity of T beta gamma or to dissociate T beta gamma from the membrane. The data suggest that MEKA attenuates the hydrophobicity of T beta gamma to result in the dissociation of T beta gamma from the membrane without directly binding to farnesyl/carboxyl-methyl moieties.

[A surgical case report of angina pectoris with multiple coronary giant aneurysms]

A 47-year-old man with sever angina pectoris was referred for surgery. Preoperative coronary angiogram revealed giant multiple aneurysms of RCA (Seg 1-Seg 3) and LCX (Seg 11) and LAD (Seg 6). Stenoses were found distal to aneurysm, 90% in RCA-Seg 4, CX-Seg 11, 100% in LAD- Seg 6 and DX-Seg 9 and OM-Seg 12, with collaterals from RCA to LAD. Left ventlicle contracted poorly with the EF of 36 due to anteroseptal infarction. Coronary artery bypass grafting were performed to LAD using a LITA, to DX and LCX using a SVG in the sequential fashion. Postoperative coronary cineangiogram demonstrated that all grafts were patent and multiple giant coronary aneurysms resembled coronary arterial changes of Kawasaki's disease.

Generation of vibrational and rotational emissions by four-wave Raman mixing using an ultraviolet femtosecond pump beam

A femtosecond KrF excimer laser is focused into molecular hydrogen to generate a multifrequency laser beam, consisting of many vibrational and rotational lines, in a transient Raman regime. The intensity distribution is unchanged from 5 to 13 atm, in contrast to the case of nanosecond laser pump. The efficiency for generation of the rotational lines is improved by increasing the peak power, especially at longer wavelengths, indicating power-dependent and wavelength-dependent behavior of this effect, as expected from theory.

Hypoaminotransferasemia in patients undergoing long-term hemodialysis: clinical and biochemical appraisal

BACKGROUND & AIMS

It has been reported that patients with chronic renal failure have low serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels as a result of vitamin B6 deficiency. Chronic hepatitis C is common among patients undergoing hemodialysis, and low aminotransferase levels cause diagnostic problems. The aim of this study was to determine the cause of hypoaminotransferasemia.

METHODS

Serum levels of vitamin B6 and its coenzyme were reassessed in relation to AST and ALT levels in patients undergoing long-term hemodialysis using high-performance liquid chromatography.

RESULTS

The mean (+/- SD) serum AST and ALT levels in 304 patients negative for hepatitis B surface antigen and anti-hepatitis C virus were 9.2 +/- 2.4 and 7.4 +/- 1.7 IU/L, respectively. In 556 normal adults, they were 22.7 +/- 5.4 and 18.0 +/- 4.0 IU/L, respectively (P < 0.001). Mean serum vitamin B6 and pyridoxal-5'-phosphate levels in patients undergoing dialysis were not reduced compared with the control, although occasionally patients had low levels. The AST and ALT assay reagents in Japan do not contain added pyridoxal-5'-phosphate; addition of pyridoxal-5'-phosphate (0.1 mmol/L) to the reagent significantly increased measurements to similar extents in both groups.

CONCLUSIONS

Serum AST and ALT levels in patients undergoing dialysis are very low, but they are not a result of vitamin B6 deficiency. The upper normal limits of AST and ALT levels in patients undergoing dialysis should be reduced considerably, and these levels should be interpreted with caution in the diagnosis of liver disease.

Interferon treatment for chronic hepatitis C in haemodialysis patients: suggestions based on a small series

Chronic hepatitis C is endemic among chronic haemodialysis patients. There have been a number of reports on hepatocellular carcinoma developing in such patients in Japan. The present study reports on the treatment of 15 patients who showed elevated ALT levels due to biopsy proven chronic hepatitis C with interferon alpha-2a (IFN). The dose schedule was 6 mega units (MU) daily for the first two weeks followed by 3 doses per week for 5.5 months. Side effects were so severe that IFN treatment was discontinued early in one patient, the dosage reduced in 11 and only tolerated in the original schedule by three patients. Excluding one patient who only recently completed the therapy, 13 were able to be evaluated for therapy efficacy by assessment of serum ALT and viral RNA. The overall results showed that IFN was effective in eight of 13 patients, a rate somewhat higher than the reported figures in this country. It is concluded that IFN therapy is indicated in haemodialysis patients with progressive chronic hepatitis C, but the dose administered should be lower and the dose schedule more flexible, perhaps 3 MU three times a week, in order to minimize untoward side effects.

Mode of hepatitis C infection not associated with blood transfusion among chronic hemodialysis patients

In a retrospective study carried out on about 730 patients with chronic renal failure who underwent ambulatory hemodialysis from January 1991 to June 1994, 49 patients were found to have developed acute hepatitis C, as confirmed by seroconversion for anti-HCV antibodies without blood transfusion in the preceding 6-month period. Epidemiological survey disclosed that two patients undergoing dialysis at consoles separated by one console developed acute hepatitis C in October 1992, and another three patients at adjacent consoles also developed acute hepatitis C within 2 weeks in April/May, 1993. It was found that some negligent nurses could have withdrawn needles from these patients one after another without changing gloves at the termination of the dialysis procedure. After reeducation of the staff members and introduction of a new type of adhesive pad to be placed on the needle wounds at the time of needle withdrawal, no new case of acute hepatitis C occurred for more than 1 year, suggesting nosocomial spread of HCV infection among hemodialysis patients in a mode that is preventable with very strict aseptic precautions.

A novel E250X mutation of the PIT1 gene in a patient with combined pituitary hormone deficiency

PIT1 abnormality is defined as a genetic abnormality in the PIT1 gene that encodes a pituitary specific transcription factor, Pit-1/GHF-1. PIT1 abnormality indicates combined deficiency of thyrotropin (TSH), growth hormone (GH) and prolactin (PRL), and has been reported in several cases. We studied the PIT1 gene in a patient with combined deficiency of TSH, GH and PRL. A novel mutation substituting a termination codon for Glutamate at 250th codon (E250X) was identified in the homozygous state in the patient. Both of the healthy parents harbored this mutation in the heterozygous state. This nonsense mutation results in complete loss of helix 3 of the POU homeodomain of Pit-1/GHF-1. As helix 3 of the homeodomain is involved directly in DNA binding, the mutant Pit-1/GHF-1 may lose the DNA binding activity of the POU homeodomain and lose its transcriptional activation. The E250X mutation is therefore considered to be the cause of the combined deficiency of TSH, GH and PRL in this patient.

Screening for PIT1 abnormality by PCR direct sequencing method

PIT1 abnormality is defined as a genetic abnormality in the PIT1 gene, which encodes a pituitary specific transcription factor Pit-1/GHF-1.PIT1 abnormality has been reported in several patients displaying either complete or incomplete deficiency of thyrotropin (TSH), growth hormone (GH), and prolactin (PRL) in either familial or sporadic cases. To see if there are abnormalities in the PIT1 gene in patients with incomplete TSH, GH, and PRL deficiency, we utilized a PCR direct sequencing method to determine the Pit-1/GHF-1 coding sequence. A total of 15 patients, 1 patient from a family with TSH and GH deficiency, 3 patients with TSH, GH, and PRL deficiency, and 11 patients treated with both human GH (hGH) and thyroid hormone were studied. In one patient of combined pituitary hormone deficiency, the Arg-271-Trp mutation was detected. Since both of the parents did not harbor this mutation, it is a de novo germ line mutation. No mutation was detected in the other patients, showing that PIT1 abnormality is not a frequent cause of GH deficiency.

[Mitral obstruction due to infective endocarditis: a case report]

Acute valvular obstruction caused by vegetation is a rare complication infective endocarditis. To our knowledge, only 9 cases and an autopsy case by Roberts have been reported since 1967. A 46-year-old man admitted with a chief complaint of pyrexia for 2 months duration. Within 24 hours of admission, the patient noticed of increased shortness of breath. Physical examination and the chest X-ray confirmed the pulmonary edema. An echocardiogram revealed a huge echogenic mass that was adherent to the mitral leaflet and obstructed the orifice completely. Soon after the patient fell into cardiogenic shock, an emergency mitral valve replacement was undertaken. At operation, multiple verrucae arising from the entire mitral leaflet was seen to occlude the orifice. The vegetation was excised and replaced with a # 25 Omnicarbon prosthesis. Postoperatively, the patient developed multiple organ failure caused by cardiogenic and septic shock which responded well to intensive medical treatment consisting of hemodialysis and continuous arteriovenous hemofiltration. Angiographically, a mycotic aneurysm in the left radial artery was found on the 18th postoperative day. After extirpation of the infective focuses, the postoperative course had stabilized. Mitral obstruction due to infective endocarditis is a fatal disease. Prompt diagnosis with echocardiogram and an emergency surgery should be undertaken to save the patient.

Detection of host DNA sequences including the H-2 locus of the major histocompatibility complex in schistosomes

The mouse type 2 Alu (B2) sequence was detected in both DNAs of Schistosoma mansoni and S.japonicum except for the cercarial stage by the polymerase chain reaction (PCR). Using several kinds of mouse STMS (sequence tagged microsatellite site) primer sets, PCR products related to the host were found in the DNAs of S. mansoni as well as of S.japonicum. Products could be detected only in the DNA of S. japonicum using certain STMS primer sets. The fact that no products could be amplified from the DNAs of both parasites when other kinds of STMS primer sets were used suggests unequal incorporation of the host DNA into the schistosomes. Furthermore, the sequence of the N-terminal domain of H-2, the mouse major histocompatibility complex (MHC), was detected in the DNAs from S. mansoni miracidium, male adult and S. japonicum adults, whereas the sequence of the C2 domain of H-2 was found only in the DNAs of S. japonicum adults. This evidence that host DNA sequences, including the class I MHC, exist heterogeneously in the DNAs of schistosomes might provide an important insight for further understanding of host-parasite immune interactions.

Plasmodium vivax malaria infection diagnosed by indirect fluorescent antibody test

We present the diagnostically challenging case of a 51-year-old Japanese male who visited Papua New Guinea for one month. Approximately a month after returning to Japan, he experienced a high fever. Malaria was suspected and he was admitted to Tsukuba University Hospital. Although the blood smear did not reveal the malarial parasite, a diagnosis of malaria was made using an indirect fluorescent antibody test (IFAT). The patient was treated and discharged but symptoms returned three months later. This time, the blood smear was positive for malarial parasites. IFAT was useful in this case for the early diagnosis of Plasmodium vivax and for ruling out infection by Plasmodium falciparum.

Serum concentrations of apolipoproteins in patients with thyroid dysfunction

We measured serum concentrations of apolipoproteins (apo A-I, A-II, B, C-II, C-III and E) in patients with thyroid disease (hyperthyroidism; n = 44, hypothyroidism; n = 15) and in normal subjects (n = 89). We found that apoA-II, B and C-III concentrations revealed significant difference among three groups of the normal (apoA-II; 31.4 +/- 4.9 mg/dl, apoB; 85.8 +/- 16.3 mg/dl, apoCIII; 7.45 +/- 2.99 mg/dl), hyperthyroidism (apoA-II; 29.8 +/- 5.4, apoB; 63.4 +/- 18.9, apoC-III; 6.28 +/- 2.45) and hypothyroidism (apoA-II; 27.5 +/- 5.3, apoB; 108.0 +/- 30.9, apoC-III; 9.43 +/- 2.74). Thyroid hormones showed clear negative correlation to apoB (r = 0.70, p < 0.001). Furthermore, apoC-III was also found to be negatively correlated with thyroid hormone concentrations (r = 0.47, p < 0.001).

Styrene-induced hepatotoxicity in mice depleted of glutathione

In mice depleted of glutathione (GSH) by pretreatment with an inhibitor of GSH synthesis, buthionine sulfoximine (BSO; 1 hr before styrene, 2 mmol/kg or higher doses, ip), styrene (0.96-5.76 mmol/kg, po) produced hepatotoxicity characterized by an increase in serum alanine transaminase activity and cetrilobular necrosis of hepatocytes. Treatment with inhibitors of hepatic cytochrome P-450-dependent monooxygenases such as carbon disulfide, methoxsalen, piperonyl butoxide, and SKF-525A prevented or tended to reduce the hepatotoxic effect of styrene given in combination with BSO. Styrene 7,8-oxide (3.84 mmol/kg, po), a known metabolite of styrene, in combination with BSO caused an earlier and larger increase in SALT than that caused by an equimolar dose of styrene in combination with BSO. These results suggest that metabolism of styrene, possibly to styrene 7,8-oxide, is a necessary step in styrene-induced hepatotoxicity in GSH-depleted mice. Before the onset of hepatotoxicity, styrene in combination with BSO produced a larger and more prolonged depletion of hepatic GSH than that seen after the sole treatment with BSO or prolonged depletion of hepatic GSH than that seen after the sole treatment with BSO or styrene, but no depletion of hepatic protein sulfhydryls was induced by styrene in combination with BSO.

The rice culture filtrate of Bacillus cereus isolated from emetic-type food poisoning causes mitochondrial swelling in a HEp-2 cell

Rice culture filtrates of Bacillus cereus SA-50, an emetic-type strain, produced a toxin which caused cytoplasmic vacuole formation in HEp-2 and HeLa cells. Electron microscopic observation revealed that the apparent vacuoles in HEp-2 seen under a light microscope were actually swollen mitochondria. The oxygen consumption of HEp-2 cells was accelerated by the addition of the rice culture filtrate as was measured with a polarographic oxymeter; a respiratory control ratio was 1.0 for control cells, while 1.4 for ones with the filtrates. The culture filtrates showed a similar effect on the isolated mouse liver mitochondria; respiratory control ratios for the mitochondria with and without the filtrates were 3.6 and 1.0, respectively. The affecting manner of the culture filtrates on the oxygen consumption of mitochondria was similar to that of 2,4-dinitrophenol, suggesting that the culture filtrate contains a toxin acting as an uncoupler of oxidative phosphorylation in mitochondria. It is likely that the culture filtrates containing the emetic toxin of B. cereus causes mitochondrial swelling with a close relationship to the uncoupling of the oxidative phosphorylation of mitochondria.

Hepatitis C infection unrelated to blood transfusion in hemodialysis patients

Hepatitis C virus antibodies were studied using both the 1st and 2nd generation tests in 485 patients who were on maintenance hemodialysis. One hundred and eighty-seven tested positive for antibodies (38.6%); 139 of them had a history of past blood transfusion. There was a crude correlation between the amount of blood given and the antibody positivity rate among those who had a history of blood transfusion. Of 152 patients who had no blood transfusion history, 48 or 31.2% were positive for the antibodies. The length of the period during which these patients had undergone dialysis was closely correlated with the positivity rate; 50% of those who had been on dialysis for more than 10 years were positive for anti-HCV. The positivity rate among the new dialysis patients with chronic renal failure as the control was 4.6%. The difference may be accounted for by nosocomial hepatitis C virus infection. It appears that with two new needle holes made along the anastomosed blood vessels two to three times a week, the chances of patient exposure to hepatitis C virus may increase with time.

[A case of unroofed coronary sinus with persistent left superior vena cava]

A 44-year-old female with left to right shunt and persistent left superior vena cava (PLSVC) suspected of unroofed coronary sinus defect with patent right SVC and innominate vein was treated surgically. PLSVC was ligated and coronary sinus ostium was closed with a EPTFE patch. Roof defect of coronary sinus was left open and allowed the coronary venous blood to drain into the left atrium. Patient recovered well and post-operative cardiac catheterization revealed no significant right to left shunt nor desaturation of arterial blood. In the correction of unroofed coronary sinus defect and PLSVC and no other intra-cardiac defect, ligation of PLSVC and closure of coronary sinus ostium was simple and effective, although it was not anatomically corrected.

Host-related DNA sequences are localized in the body of schistosome adults

The localization of host (mouse)-related DNA sequences in the adults and cercariae of Schistosoma japonicum and S. mansoni was examined by in situ hybridization using 32P-labelled probes. The hybridization signals to the sequences of the mouse type C and type A retroviruses were clearly observed in the subtegumental layer and inner tissues of S. japonicum adults. In contrast, it was hard to find any signals to these sequences in S. mansoni adults. Distinct signals to the env-specific region of the mouse ecotropic type C retrovirus were observed in the subtegumental layer and inner tissues of S. mansoni adults. No signal to the sequence of the mouse type B retrovirus was found on the sections of either schistosome adult. The signals to the sequence of the genomic clone SmM51 derived from male S. mansoni were found in the tissues of both the schistosome adults. The signals to the sequences of the mouse type A and env-specific region of ecotropic type C retroviruses were not seen in the cercariae of each species, whereas the signals to the sequence of SmM51 were detected in S. mansoni cercariae. These observations suggest that host-related DNA sequences might be incorporated unequally into the schistosome genome during development in the final host.