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T Naito

Publications and source records attributed to T Naito.

At least 163 records · Page 9Linked to original sources
PubMed1996

[A study of acute infection of herpes simplex virus in mouse trigeminal ganglia].

We investigated the shift to latency and protective reaction in mice trigeminal ganglia after inoculation of herpes simplex virus type 1 (HSV-1) onto the cornea. BALB/c mice were inoculated and the trigeminal ganglia were removed periodically. Lymphocytes in the ganglia were observed using immunocytochemical techniques. The results obtained were as follows: (1) HSV-1 positive neuronal cells were recognized at 3 days after inoculation but not at 14 days. (2) The relative proportion of T cells in lymphocytes was greater than that of B cells at 3 days, but B cells were more numerous at 5 days. Then T cells become more numerous again at 7 days. (3) Among the subsets in T cells, the ratio of CD4+ and CD8+ cells was almost equal at 3 days, but then CD4+ cells increased and CD8+ cells had disappeared at 14 days after inoculation. These results show that HSV-1 that reached the trigeminal ganglion from the cornea by axonal transport infected neuronal cells, multiplied there and then disappeared resulting in latency. Cellular immunity, especially the function of CD4+ cells, played a main role in this protective reaction by suppressing the viral growth.

Acute Disease↗
PubMed1996

Macrophage growth factors introduced into the kidney initiate renal injury.

BACKGROUND: CSF-1 expression precedes renal injury in autoimmune MRL-lpr mice and is responsible for macrophage (M phi) proliferation and survival in the kidney. By comparison, C3H-lpr mice do not express CSF-1 in the kidney, and despite the lpr mutation, kidneys remain normal. The purpose of this study was to test the capacity of local and systemic expression of M phi growth factor, CSF-1 to initiate renal injury in normal (C3H-(++), MRL-(++) and autoimmune (C3H-lpr, MRL-lpr) mice. MATERIALS AND METHODS: We designed a gene transfer system to deliver cytokines into the kidney by transducing renal tubular epithelial cells (TEC) using retroviral vectors expressing CSF-1 or another M phi growth factor, GM-CSF. We placed transduced syngeneic cytokine-TEC under the renal capsule of normal and autoimmune prone mice prior to renal injury and evaluated renal pathology at 3, 7, 14, 28, and 90 days postimplant. RESULTS: CSF-1-TEC and GM-CSF-TEC, but not uninfected TEC, caused extensive local renal injury in strains with the lpr mutation. At 3-7 days the infiltrating cells were mainly M phi, and by 28 days they were predominantly lymphocytes. By comparison, the kidneys of MRL-(++) and C3H-(++) mice remained normal. Implanted genetically modified TEC caused a sustained increase of CSF-1 or GM-CSF in the circulation which did not modify the contralateral kidney. CONCLUSIONS: Gene transfer of M phi growth factors into the kidney initiates severe local renal injury in autoimmune prone mice with the lpr mutation, but does not compromise the kidney in nonautoimmune hosts. Of note, introduction of M phi growth factors into the kidney of C3H-lpr mice which do not spontaneously develop renal injury incites renal damage. These studies offer a gene transfer approach to explore the impact of local and systemic cytokine production on renal injury.

Animals↗
PubMed1996

[Hyperventilation and cold pressor stress echocardiography for diagnosis of vasospastic angina : report of five cases].

Two-dimensional echocardiography was used for diagnosing coronary vasospasm during the cold pressor stress test immediately after hyperventilation in five patients with suspected vasospastic angina. The test consisted of hyperventilation for 6 min and cold water pressor for 2 min under continuous electrocardiographic and echocardiographic monitoring. Coronary angiography with intracoronary injection of acetylcholine was performed in all patients within 1 month after the stress test. During the stress test, new asynergies of both the anterior and inferior walls were seen in three of the five patients, and new asynergy of the anterior wall in the other two patients. All acetylcholine induced coronary artery spasms occurred at the same locations as the new asynergies provoked by the stress test. In three patients, wall motion abnormality occurred earlier than ST segment elevation, and the other two patients had no ST changes. Chest pain was induced in three patients and delayed in comparison to electrocardiographic and echocardiographic changes. Echocardiographic monitoring during the stress test could detect spasms unaccompanied by either ST segment changes or chest pain, and could detect multivessel coronary spasms. Hyperventilation and cold pressor stress echocardiography may be used for the diagnosis of vasospastic angina.

Acetylcholine↗
PubMed1996

The effect of TNP-470 on cell proliferation and urokinase-type plasminogen activator and its inhibitor in human lung cancer cell lines.

The plasminogen activator system has been found to modulate neoplastic spread and angiogenesis in tumors. An angiogenesis inhibitor, TNP-470, has been shown to possess potent antitumor activities in various types of cancer cells. We therefore investigated the inhibitory effect of TNP-470 on cancer cell proliferation, and the suppressive effect of TNP-470 on urokinase-type plasminogen activator (u-PA) and its inhibitor (PAI-1), in human lung cancer cell lines in vitro. TNP-470 inhibited cell proliferation in a dose-dependent manner in both cell lines. u-PA and PAI-1 in culture supernatants were suppressed with the concentrations of TNP-470, in association with a decrease in viable cancer cells. Unchanged serum levels of u-PA and PAI-1 would be of great advantage to the diseased patients, since the plasminogen activator system has a crucial function in the process of distant metastasis.

Antibiotics, Antineoplastic↗
PubMed1995

Restriction-modification systems as genomic parasites in competition for specific sequences.

Restriction-modification (RM) systems are believed to have evolved to protect cells from foreign DNA. However, this hypothesis may not be sufficient to explain the diversity and specificity in sequence recognition, as well as other properties, of these systems. We report that the EcoRI restriction endonuclease-modification methylase (rm) gene pair stabilizes plasmids that carry it and that this stabilization is blocked by an RM of the same sequence specificity (EcoRI or its isoschizomer, Rsr I) but not by an RM of a different specificity (PaeR7I) on another plasmid. The PaeR7I rm likewise stabilizes plasmids, unless an rm gene pair with identical sequence specificity is present. Our analysis supports the following model for stabilization and incompatibility: the descendants of cells that have lost an rm gene pair expose the recognition sites in their chromosomes to lethal attack by any remaining restriction enzymes unless modification by another RM system of the same specificity protects these sites. Competition for specific sequences among these selfish genes may have generated the great diversity and specificity in sequence recognition among RM systems. Such altruistic suicide strategies, similar to those found in virus-infected cells, may have allowed selfish RM systems to spread by effectively competing with other selfish genes.

Binding, Competitive↗
PubMed1995

Selfish behavior of restriction-modification systems.

Plasmids carrying gene pairs encoding type II DNA restriction endonucleases and their cognate modification enzymes were shown to have increased stability in Escherichia coli. The descendants of cells that had lost these genes appeared unable to modify a sufficient number of recognition sites in their chromosomes to protect them from lethal attack by the remaining restriction enzyme molecules. The capacity of these genes to act as a selfish symbiont is likely to have contributed to the evolution of restriction-modification gene pairs.

Apoptosis↗
PubMed1995

Intercostal nerve crossing to restore elbow flexion and sensibility of the hand for a root avulsion type of brachial plexus injury.

Ten patients with a root avulsion type of brachial plexus injury were treated with simultaneous intercostal nerve crossing to the musculocutaneous and median nerves, and nine cases were followed for more than 40 months. The average interval from injury to surgery was 2.7 months. The average age at operation was 18.6 years. The elbow flexor was M4 in six patients, M3 in two patients, and M1 in one patient. The wrist flexor was more than M3 in six patients and less than M2 in four patients. The finger flexor was more than M3 in four patients and less than M2 in five patients. Protective sensation in the areas innervated by the musculocutaneous and median nerves was restored in all cases.

Adolescent↗
PubMed1995

What is the most appropriate variable for estimation of mean pulmonary capillary wedge pressure by transesophageal pulsed Doppler echocardiography?

UNLABELLED: Although left ventricular (LV) inflow and pulmonary venous (PV) flow variables estimated by transesophageal Doppler echocardiography (TEE) reflect pulmonary capillary wedge pressure (PCWP), they are also affected by changes in cardiac function. The purpose of the present study was to detect the most appropriate variable for the estimation of PCWP by TEE in patients (pts) with ischemic heart disease. Several variables of LV inflow and left upper PV flow were compared with PCWP in 36 pts (six with angina pectoris and 30 with old myocardial infarction). Early diastolic flow (E) and atrial contraction flow (A) were used as LV inflow, while systolic forward flow (X), diastolic forward flow (Y) and atrial contractile reversal flow (z) were used as PV flow. The peak velocity of each flow wave (Ep, Ap, Xp, Yp, and Zp) and the time-velocity integral (Ei, Ai, Xi, Yi, and Zi) were measured. The ratio of Ep to Ap (Ep/Ap), Ei to Ai (Ei/Ai), Xp to Yp (Xp/Yp), Xi to Yi (Xi/Yi), Zp to Ap (Zp/Ap), Zi to Ai (Zi/Ai) and the systolic fraction of PV forward flow were calculated. Among these variables, the Zi/Ai ratio was most strongly correlated with PCWP (R = 0.80). The Zi/Ai ratio may not be influenced by atrial function because the augmentation of atrial pump function increases Zi as well as Ai, and this may be one reason why the ratio correlated well with PCWP. CONCLUSION: The Zi/Ai ratio is a new useful variable for estimating PCWP by TEE.

Aged↗
PubMed1995

Serum 7 alpha-hydroxycholesterol as a new parameter of liver function in patients with chronic liver diseases.

To examine bile acid synthesis in chronic liver diseases, serum total 7 alpha-hydroxycholesterol level was measured by gas-liquid chromatography-mass spectrometry in patients with cirrhosis (n = 23), patients with chronic hepatitis (n = 21), and control subjects (n = 18). The serum 7 alpha-hydroxycholesterol levels were significantly lower in patients with cirrhosis than the controls (78 +/- 59 pmol/mL vs. 237 +/- 97 pmol/mL; mean +/- SD). However, in patients with chronic hepatitis, the level was fully retained (262 +/- 102 pmol/mL). Serum 7 alpha-hydroxycholesterol levels of 17 patients with cirrhosis classified as Child B and C ranged from 33 to 69 pmol/mL, and all were less than the normal range (between 104 and 466 pmol/mL), however, those levels of some patients classified as Child A were within the normal range. Serum 7 alpha-hydroxycholesterol levels significantly correlated with serum albumin, cholinesterase, total bile acid, direct bilirubin, alkaline phosphatase, indocyanine green (ICG) retention rate, hepaplastin test, and lecithin-cholesterol acyltransferase activities. We conclude that bile acid synthesis is well preserved in patients with chronic hepatitis and that it is decreased in most patients with cirrhosis. Serum 7 alpha-hydroxycholesterol may be a new parameter of liver function testing to assess hepatic bile acid synthesis in patients with chronic liver diseases.

Adult↗
PubMed1995

Treatment of choice for choledocholithiasis in patients with acute obstructive suppurative cholangitis and liver cirrhosis.

OBJECTIVE: To identify the treatment of choice for choledocholithiasis in patients with versus without acute obstructive suppurative cholangitis (AOSC) or liver cirrhosis, the outcomes of surgical treatment and endoscopic sphincterotomy (EST) were compared. PATIENTS AND METHODS: Three hundred sixty-two consecutive patients with choledocholithiasis were divided into three groups: 27 with AOSC (Group 1), 12 with cirrhosis (Group 2), and 323 with neither AOSC nor cirrhosis (Group 3). RESULTS: Seventeen patients (63%) in Group 1 underwent emergent treatment, and 3 of them died. Two were treated by emergency surgery and both died; only 1 (7%) of 15 treated by emergent EST died. For all patients with AOSC, morbidity and mortality rates were 67% and 33% with surgery, and 24% and 5% with EST. In Group 2, 2 patients with Child C cirrhosis died after elective EST. One patient in Group 3 died. Mortality rates were significantly higher in Group 1 (11%) and Group 2 (17%) than in Group 3 (0.3%). Although comparisons between the two treatment approaches did not achieve statistical significance, EST had lower morbidity rates than surgery in both Group 1 (24% versus 67%) and Group 2 (22% versus 67%). The required hospital stay was half as long with EST as with surgery. CONCLUSIONS: EST is the recommended treatment for patients with choledocholithiasis associated with AOSC or liver cirrhosis.

Acute Disease↗
PubMed1995

Ventilatory and pulmonary vascular responses to acute hypoxia are nonuniform in healthy man.

The present study was undertaken to examine the pulmonary vascular and ventilatory responses to acute hypoxia in healthy individuals. Pulmonary hemodynamics and minute ventilation (VE) were serially measured during inhalation of 13% O2 for 15 min. There was a wide variability in the pulmonary vascular response to acute hypoxia, and a significant negative correlation between the initial increase in VE after the start of hypoxia (delta VE) and the percent increase in mean pulmonary arterial pressure (r = -0.646; p < 0.01). The fall in arterial oxygen tension significantly decreased in response to an increase in delta VE. These results support the view that a blunted ventilatory response to acute hypoxic stimulation enhances alveolar hypoxia, thereby favoring the constriction of pulmonary vasculature. Thus, our results suggest that the ventilatory response to acute hypoxia plays a significant role in the pulmonary vascular response to acute hypoxia.

Acute Disease↗
PubMed1995

Assessment of right ventricular diastolic function by pulsed Doppler echocardiography in chronic pulmonary disease and pulmonary thromboembolism.

We evaluated right ventricular (RV) diastolic performance in 12 healthy subjects (control), 25 patients with chronic pulmonary diseases (CPD) and 6 patients with chronic pulmonary thromboembolism (PTE). Flow velocity patterns were determined by the pulsed Doppler technique. The values determined included acceleration time (AT), deceleration time (DT), and the ratio of the atrial contraction wave (A) to the rapid filling wave (R) (A/R ratio) from flow velocity patterns in the RV inflow tract. DT was significantly prolonged in the CPD and PTE groups compared with the control group, indicating dysfunction during the early (middle) filling period. The prolongation was marked in those patients with pulmonary hypertension. The A/R ratio was significantly higher in the CPD and PTE groups than in the control group, indicating a decrease in RV compliance. The A/R ratio increased slightly with the increase in the end-diastolic volume index. These results suggested that the pressure overload plays an important role in RV diastolic dysfunction in patients with pulmonary disease, and that preload contributes to the dysfunction.

Aged↗
PubMed1995

Monitoring of nocturnal oxygen desaturation using pulse oximeter and apnomonitor in patients with chronic pulmonary disease.

The relationship between the degree of nocturnal oxygen desaturation (NOD) and pulmonary hemodynamics, pulmonary function tests, and resting awake blood gases was evaluated in patients with chronic pulmonary diseases (CPD). The severity of NOD correlated with the degree of impairment of pulmonary hemodynamics, but not with pulmonary function tests or resting awake blood gases. NOD was markedly alleviated by oxygen inhalation in CPD patients who did not develop sleep apnea.

Aged↗
PubMed1995

Characterization of a family of tandemly repetitive DNA sequences from the fern sawfly, Strongylogaster osmundae (Hymenoptera: Tenthredinidae).

A family of repetitive DNA sequences in the genome of the sawfly, Strongylogaster osmundae (Hymenoptera: Tenthredinidae) was characterized. The family consists of a tandemly arranged array whose basic repeat unit is 1.0 kb. According to the compositions and arrangements of bases, the basic repeat unit can be divided into three distinct domains. Three domains share nucleotide sequence homology of 88, 74 and 89%, respectively, between members in this family. Second domain which had lower homology with the other two domains was found characteristically rich with polypurine/polypyrimidine sequences.

Animals↗
PubMed1995

Molecular characterization of a family of tandemly repetitive DNA sequences (pYS family) in the genus Hemitaxonus (Hymenoptera: Tenthredinidae).

Distribution of a family of tandemly repetitive sequences in Hemitaxonus japonicus (pYS family) was investigated among eight sawfly species and host races in the genus Hemitaxonus. High copy numbers of the repetitive sequences were detected in the two host plant races of H. japonicus, race Polystichum polyblepharum (race PP) and race P. tripteron (race PT), and H. sasayamensis, whereas a low copy number in H. minomensis. Comparison of the nucleotide sequences of the basic repeat units demonstrated a high degree of homology among the four tested species with high AT-rich sequences. Minor repeat units shorter than the consensus basic repeat unit of pYS family were found only in races PP and PT of H. japonicus. Analyses of their nucleotide sequences showed the occurrence of the host race specific sub-repeat units.

Animals↗
PubMed1995

Repetitive DNA sequence families in Hemitaxonus minomensis and H. athyrii (Hymenoptera; Tenthredinidae).

Families of the repetitive DNA sequences from Hemitaxonus minomensis and H. athyrii were characterized. pHMS family and pHME family in H. minomensis consist of tandemly arranged arrays whose basic repeat units are 260 bp and 330 bp, respectively. pHAE family in H. athyrii consists of a tandemly arranged array whose basic repeat unit is 330 bp. pHMS family and pHME family occupy approximately 4.8% and 0.07% of the genome of H. minomensis, respectively. By contrast, in H. athyrii, pHAE family comprise 0.04% of the genome. Nucleotide sequence comparison of these three repetitive families showed very little homology. Southern blot hybridization using six species of Hemitaxonus showed that these repetitive families are species specific.

Animals↗