Peripheral myelin P0 protein mediates neurite outgrowth of cortical neurons in vitro and axonal regeneration in vivo

Peripheral myelin P0 protein is a homophilic adhesion molecule of immunoglobulin superfamily to compact myelin structure. In addition to its roles in formation and maintenance of myelin, P0 shows neurite-outgrowth promotion activity of dorsal root ganglions. In this paper, we examined biological activity of P0 in central nervous system (CNS). Neurite outgrowth of cortical neurons of rat embryo was markedly promoted in the co-culture on C6 transformants expressing P0 protein. The neurite outgrowth was not inhibited by the P0-glycopeptide but specifically inhibited by the anti-P0 monoclonal antibody recognizing the extracellular peptide of P0. In in vivo studies, we observed significant axonal regeneration into grafts only in animals implanted with P0-expressing transformants after spinal one-third transection. These results suggest that P0 protein has promoting activity on the neurite elongation in CNS as well as in peripheral nervous system.

The effect of some proteinase inhibitors on liquefaction of human semen

This study examined the effect of some proteinase inhibitors on liquefaction of human semen. It revealed that a strong plasmin inhibitor, 6-amidino-2-naphthyl-6-guanidinobenzoate dihydrochloride (Fusan) showed a significant inhibition of liquefaction, while t-amino caproic acid (t-ACA) showed a weak retardation effect. In terms of sperm quality after liquefaction, Fusan (10 mM), ethyl diamine tetra-acetic acid (EDTA) and Urinastatin completely inhibited sperm motility. Fusan (1 mM) and Lima bean trypsin inhibitor (LBTI) decreased sperm motility significantly, while leupeptin and t-ACA had little effect. Leupeptin, LBTI, t-ACA and Fusan (1 mM) did not affect sperm speed. 50% inhibition of sperm motility was calculated to be approximately 1.7 mM of Fusan concentration. In addition, two inhibitors, Chymostatin and Phosphoramidon were also tested with each experiment and had no effect on liquefaction or on sperm motility and speed. These results strongly suggest that plasmin may play an important role in the liquefaction process of human semen.

Clinical features of infants with primary human herpesvirus 6 infection (exanthem subitum, roseola infantum)

OBJECTIVE

To clarify clinical features of patients with primary human herpesvirus 6 (HHV-6) infection (roseola infantum, exanthem subitum) in a large-scale study.

SUBJECTS AND METHODS

Clinical signs and symptoms were analyzed in 176 infants in whom exanthem subitum was initially suspected and primary HHV-6 infection was later confirmed. The infection was proved by isolation of the virus from blood, a significant increase in the neutralizing antibody titers to the virus, or both.

RESULTS

The primary HHV-6 infection, which occurred throughout the year, was observed in 94 boys and 82 girls (mean age, 7.3 months). Fever developed in 98% (mean maximum fever, 39.4 degrees C) and lasted for 4.1 days. Macular or papular rashes appeared in 98%, on face, trunk, or both, mostly at the time of subsidence of the fever, and lasted for 3.8 days. Other clinical manifestations occurred as follows: mild diarrhea in 68%, edematous eyelids in 30%, erythematous papules in the pharynx in 65%, cough in 50%, and mild cervical lymph node swelling in 31%. Twenty-six percent had bulging of the anterior fontanelle and 8% had convulsions.

CONCLUSIONS

Clinical features of patients with virologically confirmed exanthem subitum were comparable with those described before discovery of HHV-6.

Seroepidemiology of human herpesvirus 7 in healthy children and adults in Japan

The isolation of human herpesvirus 7 (HHV-7) from saliva and blood, and the prevalence of antibodies to the virus in healthy individuals were investigated in Japan. By cocultivating samples with phytohemagglutinin-P-stimulated cord blood mononuclear cells, HHV-7 was isolated from the saliva of 1 of 20 children and from 4 of 38 adults but not from their blood. The isolates were confirmed as closely related to RK strain of HHV-7, but not to U1102 (human herpesvirus 6, HHV-6 type A) or Z29 (HHV-6 type B) strains by restriction cleavage patterns of the DNA. The virus antibody of 330 healthy children and adults was measured with an indirect immunofluorescence assay, using one of our isolates (FG7-6). The positivity rate of antibody was 40% in the first 2 months of life, declined during the first 6 months, then gradually increased and was 45% at 1-4 years of age. It reached the highest level (60%) at 11-13 years of age and was maintained until the end of the third decade, then decreased thereafter. Additionally, no simultaneous rise in the antibody titers was observed in 7 virologically confirmed exanthem subitum patients.

Clinical features of primary human herpesvirus-6 infection in an infant with acute lymphoblastic leukemia

PURPOSE

The primary infection with human herpesvirus-6 developed concurrently with diagnosis of acute lymphoblastic leukemia and initiation of intensive chemotherapy for the disease in a 4-month-old girl.

RESULTS

Prolonged viremia persisted for 7 days in the presence of neutralizing antibodies, and clinical features such as prolonged febrile and diarrheal period, no appearance of skin rash, and marked bulging fontanelle for 7 days in the absence of the virus DNA in spinal fluid may suggest an atypical clinical course of exanthem subitum and an unusual viral replication in immunocompromised condition.

Two forms of acidic arginine amidases in human kidney

Two forms of acidic arginine amidases were separated from human kidney extract using the techniques of basic ion exchange adsorption and elution as well as lima bean trypsin inhibitor (LBTI) and aprotinin affinity adsorptions and elutions. The enzymes were tentatively named acidic human renal arginine amidase-L (AHRAA-L, with affinity to an LBTI column) and -A (AHRAA-A, with affinity to an aprotinin column). Both enzymes showed a similar molecular mass of approximately 3.0 x 10(4) daltons, differing from that of human renal kallikrein (HRK, molecular mass of 4.8 x 10(4) daltons). The specific activity of AHRAA-L and -A were 106 and 680 nmol/min/A280 of Val-Leu-Arg-pNA amidolysis, respectively, and they were strongly inhibited by LBTI and human urinary trypsin inhibitor (UTI), while ethylenglycol-bis(beta-amino ethylether)-N,N,N',N'-tetraacetic acid (EGTA) showed a weak or no effect on both enzymes.

Postexposure prophylaxis of varicella in family contact by oral acyclovir

OBJECTIVE

To determine whether varicella can be prevented by administration of oral acyclovir (ACV) during the incubation period of the disease.

SUBJECTS AND METHODS

ACV (40 or 80 mg/kg daily in four divided doses) was given orally to 25 exposed infants and children for 7 days, starting 7 to 9 days after exposure from the index case in their families. Their clinical features were compared with those of 25 age-matched control subjects who had been exposed in their families but did not receive ACV. A fluorescent antibody to membrane antigen assay was used for determination of the antibody to varicella-zoster virus, and a nested polymerase chain reaction method was used for detection of viremia.

RESULTS

Among the 25 who received ACV, 4 (16%) developed the disease and 1 (4%) had a fever. On the other hand, all of 25 control subjects developed the disease and 17 (68%) had a fever. The incidence of fever and the severity of skin rashes were significantly lower (P < .01) in the subjects who received oral ACV than in the control group. Seroconversion was observed in 84% of subjects who received ACV. In some cases, varicella-zoster virus DNA was detected by polymerase chain reaction amplification in peripheral blood mononuclear cells from blood drawn approximately 14 days after exposure.

CONCLUSIONS

Varicella can be prevented or modified by administration of oral ACV late in the incubation period.

Varicella-zoster virus replication site in internal organs of an otherwise healthy child with varicella and sudden death

Pathological findings of an otherwise healthy 17 month old boy who was exposed to Varicella-zoster virus (VZV) in his family and unexpectedly died 3 days after onset of varicella are reported. They showed a disseminated VZV infection with involvement of skin, lung, liver, spleen, gastrointestinal tract and other organs where VZV antigen was detected by the enzyme-immunoassay with monoclonal antibodies to VZV. Since the subject was the full-term product of an uncomplicated pregnancy, who grew and developed normally, and had no symptoms or laboratory findings suggestive of immunodeficiency until his death, these findings suggest that many organs are involved as major internal sites of viral replication before or during infection of skin with VZV in the immunocompetent host.

Clinical and virological analyses of 21 infants with exanthem subitum (roseola infantum) and central nervous system complications

Twenty-one infants who had virologically confirmed exanthem subitum and central nervous system (CNS) complications were studied to elucidate the clinical features, laboratory and virological findings, and outcome. The primary infection with human herpesvirus 6 was confirmed by isolation of the virus from blood, a significant rise in the antibody titers to the virus, or both. All convulsive seizures (15 generalized and 6 focal) occurred during the pre-eruptive stage of exanthem subitum. Four infants with encephalitis/encephalopathy had more severe clinical features with abnormalities demonstrated on electroencephalograms and cerebral computed tomograms. All infants except those with encephalitis/encephalopathy recovered without any sequelae. One infant with encephalitis/encephalopathy developed epilepsy and another one died. Human herpesvirus 6 DNA amplified by the nested polymerase chain reaction method was detected in the cerebrospinal fluid of 6 infants, including 3 with encephalitis/encephalopathy, of 11 patients examined by the fifth day of the illness. These findings suggest that CNS complications including encephalitis/encephalopathy occur at the pre-eruptive stage of exanthem subitum, that human herpesvirus 6 invades the CNS in some patients, and that the outcome is not always benign.

[A case report of condyloma acuminatum of urethral meatus in a boy]

A 4-year-old boy was referred for treatment of papillary tumor at the urethral meatus. He was well until December 1990, when his mother noticed a tumor at the urethral meatus. The tumor was resected elsewhere. However, a similar tumor was noted again at the urethral meatus in May, 1991. The patient was admitted on September 16, 1991. Retraction of the phimotic foreskin revealed a well-demarcated papillary mass, approximately 2 x 2 mm in diameter, at the urethral meatus. There were no tumors on foreskin or glans. Under general anesthesia endoscopy was performed to locate other tumors at the urethra and bladder. No tumors were found elsewhere. Then the meatal tumor was resected surgically. Pathology was condyloma acuminatum. There was no recurrence one year after surgery. We also reviewed 24 boys with condyloma acuminatum, including 13 boys with a solitary condyloma at the urethral meatus, reported in Japan.

Promotion of metastases by tumor necrosis factor in rats bearing Dunning R3327 MAT-LyLu prostatic cancer

We examined the effects of recombinant human tumor necrosis factor (rTNF) on highly metastatic rat prostatic cancer, Dunning R3327 MAT-LyLu, in vivo. It seemed that the inhibition of tumor growth needed more than 5 x 10(5) units of rTNF and this dose was near the lethal dose. Concerning the effect of rTNF on metastasis, we found that the metastasis to lung was promoted by 1 x 10(5) units of rTNF and the promotion of metastasis was restricted by indomethacin. Although MAT-LyLu cells were producing a significant amount of prostaglandin E2, rTNF did not enhance the production. We therefore consider that the promotion of metastasis was not mediated by prostaglandin E2 from MAT-LyLu cells but was mediated by other very complicated conditions. Further studies are necessary to resolve the mechanisms.

Fatal encephalitis/encephalopathy in primary human herpesvirus-6 infection

An encephalitic illness with a fatal outcome occurred in a 9 month old girl with virologically confirmed exanthem subitum. Human herpes-virus-6 (HHV-6) DNA was found in the cerebrospinal fluid at the acute stage of the disease by the polymerase chain reaction, but the virus antigen was not detected in her brain tissue. This suggests that HHV-6-induced encephalitis/encephalopathy may be due to a non-infectious process.

Activation of human herpesvirus-6 in children with acute measles

Virological and serological studies were carried out prospectively to evaluate the possible activation of human herpesvirus-6 (HHV-6) in 50 infants and children with acute measles by isolation of HHV-6 from peripheral blood and by determining neutralizing antibodies to the virus. All but 5 patients (90%) were seropositive to HHV-6 in the acute stage of measles and 18 (40%) had a significant increase in HHV-6 antibody titers thereafter, whereas only 2 of 27 patients who were initially seropositive to Epstein-Barr virus (EBV) viral capsid antigen (VCA) had a significant rise in antibody titers to EBV VCA. Among 18 patients with a significant increase in HHV-6 titers, the virus was isolated from the peripheral blood mononuclear cells of three patients in the early convalescent stage of measles. These results indicate that activation of HHV-6 may occur frequently a few weeks after primary infection with the measles virus.

A prospective study of human herpesvirus-6 infection in renal transplantation

Sixty-five kidney transplant recipients and their (22 living related and 43 cadaveric) donors were studied prospectively to determine the relationship between kidney transplantation and human herpesvirus-6 (HHV-6) infection. The virus isolation from peripheral blood and other tissues and sequential determination of neutralizing antibodies to HHV-6 were performed during 3 months following the transplantation. All of the donors and their recipients examined had neutralizing antibodies to HHV-6 at the time of renal transplantation and the virus was not isolated from them. HHV-6 was isolated from 3 renal tissues (2 living related and 1 cadaveric) obtained during transplant surgery, but not from their blood at that time. HHV-6 viremia occurred in 9 (14%) of the 65 recipients around 2 to 4 weeks after the transplantation. An additional 27 recipients showed a significant rise in the antibody titer. Thus, the infection with HHV-6 was confirmed in 36 (55%) of the 65. These results indicate that the virus is activated in many cases in the early posttransplant period and that HHV-6 establishes in vivo latency in the kidney tissue. There was no correlation between HHV-6 infection and acute rejection or the antirejection prophylaxis.

[Traumatic intracranial aneurysms after removal of tuberculum sellae meningioma: case report]

Two cases of traumatic aneurysms (TA) of the internal carotid artery (IC) due to removal of tuberculum sellae meningioma (TSM) are presented, and ideal treatment of those aneurysms is discussed. The tumor, compressing the IC laterally, was removed out without arterial injury in case 1. Though the patient's postoperative course was uneventful, frontal and intraventricular hemorrhage developed 2 months after the operation, and an IC dorsal aneurysm was detected. Preoperative angiograms showed no aneurysm, so it was considered to be a traumatic aneurysm due to the surgical procedure. The aneurysm was clipped at once, but postoperative angiograms showed recurrence of the aneurysm. IC balloon occlusion was carried out as the Matas test was negative. In case 2, a small tear in the IC was inadvertently made during recurrent TSM removal, which was wrapped with muscle using fibrin glue. 2 weeks after the operation, frontal hemorrhage developed. Angiograms revealed a small aneurysm of the IC, which was considered to be a traumatic aneurysm. IC balloon occlusion was performed as the Matas test was negative. These 2 patients have had no episodes of rerupture after the IC balloon occlusion. Tumors and main arteries are frequently adhesive, so arteries are easily injured during removal of meningiomas. Muscle wrapping was not enough to prevent TA formation. Neck clipping was not appropriate for treatment of TA, but IC balloon occlusion was an effective and excellent therapy for TA of IC.

Glycopeptide of P0 protein inhibits homophilic cell adhesion. Competition assay with transformants and peptides

Expression of major myelin glycoprotein P0 by P0 cDNA transfection into C6 glioma cells promoted homophilic cell adhesion of the cells. After the dissociated cells were incubated for various times, the number of particles at each time point was measured. The total number of particles decreased to 24% in 60 min for transformant (C6P0) cells, in contrast to only 68% for control (C6P0') cells. To confirm the homophilic mechanism of adhesion, mixed-cell aggregation experiments were performed. Among the four synthetic peptides corresponding to a part of the P0 sequence used, only peptide 3 (residues 90-96), which contained a carbohydrate attaching site, caused considerable inhibition of cell aggregation (approximately 50%). In addition, the glycopeptide (residues 91-95) obtained from bovine P0 markedly inhibited cell aggregation (by approximately 85%).

Comparison of severity of viremia and antibody responses between infants and children with measles

Severity of viremia and neutralizing antibody responses were compared between nine young infants (less than or equal to 10 months) with measles and 18 infants and children (greater than or equal to 11 months) with ordinary measles. Peripheral blood mononuclear cell (PBMC)-associated viremia was detected between the first day of elevation of fever (day 0) and day 5 of the disease in the former group, whereas PBMC-associated and cell-free viremia were detected between day 0 and day 14 in the latter group. The number of infected PBMC during the first 7 days of the disease was 3.22 +/- 1.07 (log10, mean +/- s.d.) per 10 million PBMC in the former group, which was significantly smaller (P = 0.02) than that of the latter group (4.21 +/- 1.18). The former group reached the maximum level of antibody earlier than the latter group.

Endonuclease analyses of DNA of human herpesvirus-6 isolated from blood before and after bone marrow transplantation

Three strains of human herpesvirus-6 (HHV-6) were isolated from peripheral blood mononuclear cells of a leukemic child with the antibody of HHV-6 before and after bone marrow transplantation (BMT); two strains were obtained before BMT and one after BMT. The DNA extracted from the three isolates was analyzed by six different restriction endonucleases. The cleavage profiles of two strains obtained before BMT were different, but the third strain isolated after BMT was identical with one of the two, which suggest reactivation of HHV-6 from the recipient's own body after BMT and possible mutation or super-infection of the virus in an immunocompromised patient.

Testicular injury: late results of semen analyses after uniorchiectomy

Semen parameters from 4 patients with testicular injury after uniorchiectomy were investigated. Semen volume and sperm morphology were not affected after the operation, but sperm count and motility were severely diminished. Two of 4 cases showed azoospermia, and the other 2 cases showed low values in both sperm count and motility. After 150-300 days from the operation, 2 cases recovered to the normal range in sperm count while the other 2 remained in the abnormal range. In sperm motility, 3 cases recovered to the normal range but the rest remained abnormal. The results suggest that long-term follow-up in semen parameters is needed when unilateral orchiectomy is performed.

[Surgical exploration for renal cyst: two-case report]

A 59-year-old male was admitted to our clinic for further examination of the calcified renal cyst discovered incidentally on medical workup elsewhere. CT showed a left renal cyst associated with calcification. Ultrasound-guided puncture of the renal cyst was not successful because of thickness of the cystic wall. Renal angiography showed hypervascularity of the cystic wall. Association of renal cell carcinoma could not be ruled out, therefore the exploration was performed. Histological examination revealed benign renal cyst with calcification. A 27-year-old male presented with the chief complaint of left flank pain. Following examinations by US, CT and MRI, a renal cyst associated with renal cell carcinoma was highly suspected. Subsequent exploration revealed cluster of cysts with a yellowish lesion a few mm in diameter. Frozen section revealed no malignancy, and cystic fluid was not hemorrhagic. Therefore as many cystic walls as possible were removed without nephrectomy. Histological examination of the permanent specimen revealed renal cell carcinoma. Renal cyst associated with renal cell carcinoma was regarded as rare clinical entity, but such cases are reported in increasing number in recent years. We report such cases and review the pertinent literature in this paper.

IgM neutralizing antibody responses to human herpesvirus-6 in patients with exanthem subitum or organ transplantation

The assay for detecting IgM neutralizing (NT) antibody activity to human herpesvirus-6 (HHV-6) was developed by using pretreatment of blood sample with staphylococcal protein A. The activity was mostly present in IgM fractions of serum but not in IgA fractions separated by ultracentrifugation. The assay was used for seroepidemiological studies for HHV-6 infection. In primary HHV-6 infection, IgM NT antibodies appeared 5 to 7 days after onset of exanthem subitum, reached maximum titers at 2 to 3 weeks, and tended to decline to undetectable levels after 2 months. In contrast, reactivation of HHV-6 observed in organ transplants showed somewhat greater degree of IgM NT antibody responses that persisted for 2 to 3 months and became undetectable 5 to 6 months after transplantation. The level and persistence of NT antibody titers measured by the conventional method was generally greater than those of the IgM titers. The prevalence of the IgM NT antibodies was examined in healthy individuals. The antibody was first detected at 4 to 7 months of age (5%), reached maximum level at 8 to 11 months (40%), and was detectable by 4 to 6 years (17%). A few (4 to 5%) of adolescents and adults were positive for the antibody.