Cytomegalovirus infection of the central nervous system stem cells from mouse embryo: a model for developmental brain disorders induced by cytomegalovirus

Cytomegalovirus (CMV) is the most frequent infectious cause of developmental disorders of the central nervous system (CNS) in humans. Infection of the CNS stem cells seems to be primarily responsible for the generation of the brain abnormalities. In this study, we evaluated the infectivity of murine CMV (MCMV) in epidermal growth factor (EGF)-responsive CNS stem cells prepared from fetal mouse brains, and studied the effect of infection on growth and differentiation of the stem cells. The CNS stem cells were permissive for MCMV infection, although MCMV replication was slower than in mouse embryonic fibroblasts. MCMV infection inhibited the growth and DNA replication of the stem cells. A clonogenic assay revealed that MCMV infection suppressed generation of colonies from single stem cells. When uninfected stem cells were induced to differentiate, a decrease in expression of the primitive neuroepidermal marker nestin was observed by immunocytochemistry and flow cytometry, whereas expression of neurofilament and glial fibrillary acidic protein (GFAP) were induced. In virus-infected CNS stem cells, nestin expression was retained, whereas the expression of neurofilament was more severely inhibited than that of GFAP in these cells. Two-color flow cytometry showed that differentiated glial precursor cells were preferentially susceptible to MCMV infection. MCMV-infected and uninfected CNS stem cells were transplanted into the neonatal rat brains. The reduced number of infected stem cells were engulfed into the subventricular zone and expressed GFAP, but did not migrate further, in contrast to the uninfected stem cells. These results suggest that suppression of the growth of the CNS stem cells and inhibition of the neuronal differentiation by CMV infection may be primary causes of disorders of brain development in congenital CMV infection.     

In vitro activity of (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)-adenine against newly isolated clinical varicella-zoster viras strains

The highly potent and selective anti-DNA virus agent (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine [(S)-HPMPA] was found to inhibit in vitro the replication of a number of clinical varicella-zoster virus strains within the concentration range of 0.63—5.7 ng/ml. With a mean 50 % inhibitory concentration of 1.8 ng/ml and selectivity index of 29000, (S)-HPMPA is one of the most potent and most selective varicella-zoster virus inhibitors discovered to date.     

A case of leiomyoma of the lamina muscularis mucosae of the esophagus with a complication of carcinoma in situ of the overlying mucosa

An extremely rare case of leiomyoma originating in the lamina muscularis mucosae of the esophagus with a complication of carcinoma in situ in its overlying mucosa was reported. The patient was a 53-year-old male who complained of a feeling of abdominal fullness. A small, elevated tumor was found in the middle portion of the esophagus by esophagoscopy. Biopsy specimens showed it to be squamous cell carcinoma. The resected material revealed the tumor mass to be composed of both a leiomyoma, measuring 0.8 x 0.6 x 0.25 cm, which continued from the lamina muscularis mucosae, and carcinoma in situ and dysplasia in the overlying mucosa of the leiomyoma. The mucosa apart from that covering the leiomyoma was intact. It was speculated that chronic stimulation of the epithelium covering the leiomyoma might have induced the dysplasia and carcinoma in situ.     

Small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features of the thoracic wall: A case report with histological,immunohistochemical and ultrastructural examinations

A case of small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features is presented. The tumor was encountered in a 32 year old Japanese woman with an initial presentation of palpable tumor in the left lateral region of the thorax. The resected tumor was a partially well encapsulated whitish medullary one and consisted of small round and spindle tumor cells, together with so-called rhabdoid cells in the small round cell area. Although pseudorosettes were often observed, true rosette formation could not be detected anywhere. Ultrastructurally, despite a histologic variety of tumor cells, most tumor cells possessed numerous mitochondria, some of which occasionally contained abnormal filamentous or crystalloid structures. Various amounts of microfilaments were present in most tumor cells and microtubules were present in a few. A minority of small round cells possessed a small number of neurosecretory granules, especially in short cytoplasmic processes. A positive immunoreaction for neuron specific enolase was found by immunohistochemical examination in several small round tumor cells and for neurofilaments in lesser numbers. Despite the lack of S-100 protein, MB2 was detected in both small round and spindle cells. On the basis of these findings, the tumor of the present case corresponds to malignant peripheral nerve sheath tumor with neuronal differentiation and oncocytic features.     

Rapid serodiagnosis of active pulmonary Mycobacterium tuberculosis by analysis of results from multiple antigen-specific tests

We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis.     

Relationship between glucose transporter and changes in the absorptive system in small intestinal absorptive cells during the weaning process

In the present study, we investigated the changes in the localization of the glucose transporter GLUT2 and the fructose transporter GLUT5 in small intestinal absorptive cells during postnatal development, especially during the weaning period, using immunohistochemistry and confocal laser scanning microscopy. In the jejunum, GLUT2 was observed within the apical and basolateral membrane domain of absorptive cells, especially in the middle part of the villi. In the suckling rat ileum, GLUT2 was found within the apical and basolateral membrane domain of absorptive cells, but after 18 or 19 days after birth, GLUT2 was found mainly within the apical membrane domain. GLUT5 was observed within the apical membrane domain of absorptive cells in the suckling rat jejunum. In the 18- or 19-day-old rat jejunum, GLUT5 was localized within the apical and basolateral membrane domain of absorptive cells in the lower part of the villi, but after weaning, GLUT5 was found within the apical and basolateral membrane domain of absorptive cells throughout the entire villi. In the suckling rat ileum, there was little GLUT5 in the absorptive cells. In the 18- or 19-day-old rat ileum, GLUT5 was localized within the apical membrane domain of absorptive cells in the lower part of the villi, but after weaning, GLUT5 was observed mainly within the apical membrane domain of absorptive cells throughout the entire villi. These results suggest that the localization of glucose transporters corresponds with a shift from neonatal-suckling to weaned absorptive cells during postnatal development.     

Advance in animal experiments with the undulation pump total artificial heart: 50 and 54 day survival periods with 1/R control

The undulation pump total artificial heart (UPTAH) is a unique, implantable, total artificial heart (TAH) that uses undulation pumps. To achieve long-term survival in animals with physiologic hemodynamic conditions, a control method based on conductance and arterial pressure was applied to UPTAH. With this control method, called 1/R control, survival periods of 50 days (No. 0016, 49.6 kg) and 54 days (No. 0030, 42.5 kg) were obtained in adult female goats. In No. 0016, 1/R control was applied to the left pump, whereas in No. 0030, it was applied to the right pump. Another pump was used for left-right balance control. The control stability was better in No. 0030 than in No. 0016. The sucking effect of the left atrium was remarkable in No. 0016, possibly because of a time delay when left-right balance control was performed with the right pump. In No. 0016, the cause of death was probably a thrombus flown from a panus in the left atrium. It is possible that the left atrial suction effect influenced the thrombus and panus formation in the left atrium. In No. 0030, the cause of death was a small rupture of the membrane in the right pump. The rupture may have been caused by excessive negative pressure inside the pump. This pressure resulted from suction of the right atrium because of an unexpected control excursion, which was probably caused by a software bug. It will be necessary to redesign the undulation pump and improve the software to achieve longer survival periods for animals with physiologic hemodynamic conditions.     

Mutational screening of APP gene in patients with early-onset Alzheimer disease utilizing mismatched PCR-RFLP

To elucidate the frequency of mutations of the β/A4 amyloid protein precursor (APP) gene in early-onset Alzheimer disease, we designed a mismatched PCR-RFLP that can identify all kinds of missense mutations at codon 717 in addition to the seven kinds of known mutations at exon 17. When we screened mutations at exon 17 utilizing this method and the double missense mutations at exon 16 of the APP gene by PCR-RFLP, no cases revealed mutations of the APP gene among 13 familial and 54 sporadic cases, except one family (OS-1) that had previously been reported and used as a positive control of APP717(Val → Ile). Our results support the hypothesis that mutations in the APP gene are not major causes in early-onset Alzheimer disease.     

Results of animal experiments using an undulation pump total artificial heart: analysis of 10 day and 19 day survival

An undulation pump is a special rotary blood pump in which rotation of a brushless DC motor is transformed to an undulating motion by a disc in the pump housing attached by means of a special link mechanism. In the blood pump, a closed line between the disc and housing moves from the inlet to the outlet by this undulating disc motion, which sucks and pushes the blood from the inlet to the outlet. Because the same phenomena occurs at both sides of the disc, a continuous flow is obtained when the motor rotational speed is constant. The pump flow pattern can be easily changed from continuous flow to pulsatile flow by controlling the motor drive current pattern. A seal membrane made of segmented polyurethane protects the blood from invading the link mechanism as well as the motor. UPTAH is fabricated with two undulation pumps and two brushless DC motors. Its size is 75 mm in diameter and 80 mm long, and it has one of the great advantage of no compliance chamber required in the system. UPTAHs were implanted under cardiopulmonary bypass (CPB) into the chest cavities of 16 goats, each weighing between 41 and 72 kg. No anticoagulant and antiplatelet agent was used after the surgery. The left atrial pressure was automatically controlled to prevent its elevation and sucking of the atrial wall into the atrial cuff. The following results were obtained: (1) UPTAHs fit well into all the goats; (2) the longest survival was 19.8 days, the cause of death was bleeding from the aortic anastomosis; (3) No thrombus was observed in the blood pump despite no anticoagulant use. Hemolysis depended upon the length of CPB during surgery. When CPB time was within 2 hours, hemolysis level returned to baseline within a few days of the surgery. UPTAH is a promising implantable TAH, because of its small size and easy controllability.