Search PubMed⌕ Search

Biomedical subjects

M Honda

Publications and source records attributed to M Honda.

At least 109 records · Page 6Linked to original sources
PubMed2000

Direct detection of apoptotic cells in peripheral blood from highly pathogenic SHIV-inoculated monkey.

Apoptosis in peripheral blood leukocytes (PBL) has been estimated by the enhancement of spontaneous apoptosis after in vitro culture, because apoptotic cells have not been observed directly in freshly isolated PBL in the course of HIV/AIDS. In monkeys infected with a highly pathogenic simian/human immunodeficiency virus (SHIV), which corresponds to rapid progressors of HIV infection, a high frequency of apoptotic cells was directly detected in fresh PBL by electron-microscopic studies. Peripheral blood apoptosis transiently occurred after intense plasma viremia, and peaking at 3 weeks postinfection; occurrence was not limited specifically to lymphocytes, but also occurred in other types of leukocytes. Apoptosis in peripheral lymph nodes was also detected following intense plasma viremia. However, the in vivo apoptosis was not detected in nonpathogenic SHIV-infected monkeys that showed no cell loss. Thus, we directly showed the apoptosis of PBL, which might be associated with pathogenic SHIV produced during the time of plasma viremia.

Animals↗
PubMed2000

Recombinant bacillus Calmette-Guérin as a potential vector for preventive HIV type 1 vaccines.

In August 1997, the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) convened an expert working group to discuss current strategies for the development of HIV type 1 vaccines. Based on the recent findings of investigators from Japan's National Institute of Infectious Diseases (NIID) in Tokyo using recombinant bacillus Calmette-Guérin (rBCG) as a potential vectored vaccine for HIV, a recommendation was made that further work in this area is a priority. As a result, the working group reconvened in September 1998 to discuss the progress to date with this vaccine approach, as well as areas of related research to assess the feasibility of a BCG-vectored HIV vaccine. This report summarizes the discussions addressing the available scientific data on the potential use of rBCG as a vector for preventive HIV vaccines, the work necessary to move such candidate vaccines into Phase 1 clinical trials, and recommendations targeted at facilitating the long-term development of rBCG-vectored HIV vaccines.

AIDS Vaccines↗
PubMed2000

Prospective study of hepatitis B and C viral infections, cigarette smoking, alcohol consumption, and other factors associated with hepatocellular carcinoma risk in Japan.

This community-based prospective study examined the effects of viral infections and lifestyle habits on hepatocellular carcinoma (HCC) risk in Japan. A baseline survey was conducted for 981 males and 2,078 females in June 1992 and evaluated hepatitis B surface antigen, second-generation hepatitis C virus antibody, and history of cigarette smoking and habitual alcohol consumption. By March 1997, 14 males and 8 females had been newly diagnosed with HCC. After controlling for gender and age by using the Cox model, the authors found that positivity for hepatitis B surface antigen (hazard ratio = 7.28, 95% confidence interval: 1.62, 32.61; p < 0.01) and positivity for high-titer hepatitis C virus antibody (hazard ratio = 40.38, 95% confidence interval: 11.71, 139.21; p < 0.001) were significantly associated with HCC risk, although a history of smoking or alcohol consumption was not significantly related to risk. There was a significant interaction on an additive scale for the risk of HCC development between high-titer hepatitis C virus antibody status and a history of smoking (p < 0.05) in spite of no significant interaction on a multiplicative scale. Although preventing the transmission of hepatitis viruses is most important for reducing the risk of HCC, intervention regarding lifestyle habits such as cigarette smoking should not go unheeded.

Adult↗
PubMed2000

Columnar epidermal necrosis: a unique manifestation of transfusion-associated cutaneous graft-vs-host disease.

BACKGROUND: In 1978, the first case of columnar epidermal necrosis was reported in a 6-year-old boy. There were scaly, partially vesicular or crusty, erythematous lesions mainly involving the extremities that histopathologically showed peculiar features of focal, total epidermal necrosis accompanied by a lichenoid tissue reaction. He developed the skin eruption after receiving a blood transfusion from his mother when he showed debility induced by vaccination with an alternated live measles virus vaccine. The lesions rapidly regressed after sun exposure. To our knowledge, there has been no report of a similar case despite such unique features. OBSERVATION: We encountered a similar case of columnar epidermal necrosis in a 15-year-old Japanese girl with chronic graft-vs-host disease; the lesions occurred 3 months after the transfusion of peripheral blood stem cells from her HLA antigen-matched brother. However, there was no exacerbation of liver dysfunction, diarrhea, or bone marrow aplasia. The peculiar cutaneous lesions responded well to topical phototherapy. CONCLUSION: These 2 patients shared a similarity in their lesions and circumstances under which the blood transfusion was performed to a debilitated patient from a close family member. We believe that focal epidermal necrosis observed in patients with this condition represents a variant of blood transfusion-associated lichenoid graft-vs-host disease that occurs uniquely in a skin-targeted fashion.

Adolescent↗
PubMed2000

Toward neuroanatomical models of analogy: a positron emission tomography study of analogical mapping.

Several brain regions associated with analogical mapping were identified using (15)O-positron emission tomography with 12 normal, high intelligence adults. Each trial presented during scanning consisted of a source picture of colored geometric shapes, a brief delay, and a target picture of colored geometric shapes. Analogous pictures did not share similar geometric shapes but did share the same system of abstract visuospatial relations. Participants judged whether each source-target pairing was analogous (analogy condition) or identical (literal condition). The results of the analogy-literal comparison showed activation in the dorsomedial frontal cortex and in the left hemisphere; the inferior, middle, and medial frontal cortices; the parietal cortex; and the superior occipital cortex. Based on these results as well as evidence from relevant cognitive neuroscience studies of reasoning and of executive working memory, we hypothesize that analogical mapping is mediated by the left prefrontal and inferior parietal cortices.

Adult↗
PubMed2000

Phylogenetic relationships, character evolution, and biogeography of the subfamily Lygosominae (Reptilia: Scincidae) inferred from mitochondrial DNA sequences.

Phylogenetic relationships among the lygosomine skinks were inferred from 1249 base positions of mitochondrial DNA sequences of 12S and 16S rRNA genes. The monophyly of this subfamily was confirmed and the presence of five distinct infrasubfamilial lineages detected. Of these, the Sphenomorphus group appears to have diverged first, followed by the Lygosoma and Egernia groups in order, leaving the Eugongylus and Mabuya groups as sister groups. Our results did not support monophyly of the Mabuya group sensu lato (i.e., an assemblage of the Lygosoma, Egernia, and Mabuya groups), for which a number of morphological and karyological studies demonstrated a considerable similarity. Our results also contradict the previous hypothesis, formulated on the basis of morphological and immunological data, which argued for the sister relationship between the Egernia and the Eugongylus groups. Morphological and karyological characters used to define the Mabuya group (sensu lato) may actually represent plesiomorphic states. The phylogenetic diversity of lygosomine skinks in the Australian region appears to have increased through multiple colonizations from Southeast Asia.

Animals↗
PubMed2000

Desynchronization and synchronization of central 20-Hz rhythms associated with voluntary muscle relaxation: a magnetoencephalographic study.

To clarify the cortical mechanisms involved in motor inhibition, modulation of cortical rhythms around 20 Hz during voluntary muscle relaxation was compared to that during muscle contraction in ten normal volunteers, using a whole head type neuromagnetometer. Each subject relaxed or contracted the right forearm muscles, from which electromyograms were recorded. After bandpass filtering magnetoencephalographic signals into frequency bands of 6-10, 10-14, 14-18, 18-22, 22-26, and 26-30 Hz, the signals of each frequency band were rectified and averaged with respect to the onset of motor trial. The relaxation task showed movement-related 20-Hz desynchronization over bilateral central areas beginning a few seconds before the termination of muscle contraction. Twenty-hertz desynchronization was present also for the contraction task at the same location within each subject. The two tasks had a positive correlation among subjects in both the percent decrease (r2=0.76, P<0.01) and the peak time (r2=0.61, P<0.05) for the contralateral 20-Hz desynchronization. After the muscle relaxation, desynchronization was followed by conspicuous movement-related synchronization of the 20-Hz passband in the contralateral central areas, which was significantly larger than that after the contraction (P<0.001). The results suggest that the voluntary muscle relaxation involves the modulation of central rhythms starting a few seconds before the actual event, and the 20-Hz desynchronization has a similar temporal property in the muscle relaxation and contraction. The 20-Hz synchronization in the contralateral central area after the muscle relaxation may be associated with the temporally arrayed termination of the ongoing muscle contraction.

Adult↗
PubMed2000

Primary malignant lymphoma of the maxillary sinus: CT and MRI.

We reviewed the CT and MRI of seven patients with primary malignant lymphoma of the maxillary sinus to find if there are characteristic imaging findings suggestive of the disease. The images were analysed for appearance, size, signal, internal characteristics, extent of tumour, bone change and lymph node enlargement. In two patients, the tumour first presented with mucosal thickening. In the remaining five, the tumours were an expansile mass 4-6 cm in diameter at the time of detection. Although it was difficult to distinguish tumour from mucosa or obstructed fluid on CT, T2-weighted MRI enabled us to separate tumour from normal mucosa or fluid. In two patients, the tumours were heterogeneous. Calcification and haemorrhage were observed in one patient. Periantral soft-tissue infiltration was always present, even when tumour appeared as slight mucosal thickening. Posterior extension was seen in all patients. Permeative and lytic bone destruction accompanied most cases of periantral soft-tissue infiltration; mixed destruction and sclerosis was also observed. Mucosal thickening with periantral soft-tissue infiltration may suggest malignant lymphoma of the maxillary sinus in its early form. Various types of bone change may accompany the periantral soft-tissue infiltration.

Adult↗
PubMed2000

Sclerosing encapsulating peritonitis in pediatric peritoneal dialysis patients.

The aim of this study was to define the incidence and characteristics of sclerosing encapsulating peritonitis (SEP) in pediatric peritoneal dialysis (PD) patients in Japan. A questionnaire was sent to all dialysis units with at least two pediatric PD patients. Among 687 patients registered, 11 cases (1.6%) of SEP were diagnosed. The mean age of patients with SEP at the start of PD was 9.7+/-3.6 years and at SEP diagnosis, 19.1+/-3.8 years. All patients had undergone PD for more than 5 years, and the mean PD duration was 9.6+/-3.3 years. SEP was diagnosed in 6.6% and 12% of patients dialyzed for >5 years and >8 years, respectively. The incidence of peritonitis among patients with SEP was not different from that among the Japanese pediatric registry. All patients had virtually no residual urine volume and 9 had impaired peritoneal ultrafiltration. Peritoneal calcification was the most-frequent radiological finding. Peritoneal biopsy was performed in 7 patients and confirmed sclerotic peritonitis in all. Ten patients transferred to hemodialysis, and only 1 patient underwent surgery. Three patients died. We recommend that patients on PD for more than 5 years who have impaired peritoneal ultrafiltration or peritoneal calcification should be carefully managed as presumptive cases of SEP.

Adolescent↗
PubMed2000

A giant urinoma in a neonate without obstructive uropathy.

We report a neonate with a giant urinoma and renal failure. A 7-day-old boy had a giant abdominal mass of 6.5 cm x 8 cm in the right quadrant, gastroesophageal reflux, and renal failure caused by the compression from the mass. Radiological observations revealed a multiseptated cyst and neither kidney could be detected. To relieve these symptoms percutaneous drainage was performed. The contents of the fluid were similar to the patient's urine. The symptoms were improved by the drainage, and we found the left kidney to be absent and the right kidney small. Four prenatal ultrasound scans detected no cystic lesions in his abdomen. Neonatal urinomas are commonly complicated by obstructive uropathy, such as posterior urethral valves or ureteropelvic junction obstruction. These obstructive uropathies were ruled out by retrograde pyelography and voiding cystourethrography. A severely dilated upper pole of a double collecting system was also ruled out by intravenous pyelography and direct observation of the kidney during an open biopsy. The cause of the urinoma is still uncertain, but trauma during delivery and the dysplastic right kidney may be involved.

Cysts↗
PubMed2000

Expression of glucocorticoid receptor beta in lymphocytes of patients with glucocorticoid-resistant ulcerative colitis.

BACKGROUND & AIMS: Recently, the glucocorticoid receptor beta (hGRbeta) was suggested to play a role as a dominant negative regulator for determining glucocorticoid response. The aim of this study was to clarify whether reverse-transcription polymerase chain reaction (RT-PCR) analysis of hGRbeta messenger RNA (mRNA) can predict the response to glucocorticoids in patients with ulcerative colitis. METHODS: Total RNA obtained from peripheral blood mononuclear cells (PBMCs) of 23 patients with ulcerative colitis and 20 healthy volunteers was reverse transcribed; the resulting complementary DNA was amplified using specific primers for hGRalpha and hGRbeta. Protein expression of hGR in PBMCs was confirmed by immunoprecipitation-Western blot analysis. RESULTS: The expression of hGRalpha mRNA (477 base pairs) was detected in all patients and all healthy volunteers. In contrast, a hGRbeta mRNA (366 base pairs) was detected in 1 (9.1%) of 11 glucocorticoid-sensitive patients, 10 (83.3%) of 12 glucocorticoid-resistant patients, and 2 (10%) of 20 healthy volunteers. The positive rate of hGRbeta mRNA in the resistant group was significantly higher than that in the sensitive group (P = 0.0019). The hGRbeta band could be detected by immunoprecipitation-Western blotting in hGRbeta mRNA-positive patients. CONCLUSIONS: The results show that the expression of hGRbeta mRNA in PBMCs examined by RT-PCR may serve as a novel predictor of glucocorticoid response in ulcerative colitis.

Adolescent↗
PubMed2000

Cell cycle regulation of hepatitis C virus internal ribosomal entry site-directed translation.

BACKGROUND & AIMS: Translation of the hepatitis C virus (HCV) polyprotein is mediated by an internal ribosome entry site (IRES) that is located within the 5' nontranslated segment of the viral RNA. This RNA segment is known to form binary complexes with isolated 40S ribosome subunits in vitro, but there is little understanding of how the process of virus translation is regulated in vivo. METHODS: We established 2 stably transformed cell lines from Huh-7 cells that constitutively express dicistronic RNA transcripts containing sequences encoding 2 reporter proteins (Renilla luciferase and firefly luciferase) separated by a functional HCV IRES. The translation of the upstream Renilla luciferase reading frame is initiated in these cells by the usual cellular cap-dependent mechanism, whereas translation of the downstream firefly luciferase reading frame is initiated by the IRES. RESULTS: Compared with cap-dependent translation, the activity of the IRES was greatest in actively growing cells and relatively reduced in resting cells. In synchronized cultures of these stably transformed cells, the IRES activity varied with the cell cycle and was greatest during the mitotic (M) phases and lowest during the quiescent (G(0)) phases. CONCLUSIONS: These findings suggest that HCV translation is regulated by cellular proteins that vary in abundance during the cell cycle and that viral translation may be enhanced by factors that stimulate the regeneration of hepatocytes in patients with chronic hepatitis C.

5' Untranslated Regions↗
PubMed2000

Correlation of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, and clinical features of hematological disorders: a pilot study.

The 8-hydroxy-2'-deoxyguanosine (8-OHdG), presently the most popular marker for oxidative DNA damage, level has been reported to be elevated in patients with various malignancies. In the present study, urinary 8-OHdG was examined in 44 patients with hematological disorders (13 malignant lymphoma, 11 adult T cell leukemia/lymphoma (ATL), 10 acute leukemia, and 10 myelodysplastic syndrome (MDS)) by an enzyme-linked immunosorbent assay. The pre-therapy level of urinary 8-OHdG in ATL patients was significantly elevated compared with normal controls (25.3+/-12.9 vs. 11.9+/-7.3 ng/mg, P<0.05). Although patients with lymphoma, acute leukemia and MDS also showed higher urinary 8-OHdG levels than normal controls, the differences were not significant. However, two patients with refractory anemia with excess blasts in transformation (RAEB-t) having extreme monocytosis and neutrophilia showed exceptionally high urinary 8-OHdG levels (161.0 and 218.9 ng/mg). Urinary 8-OHdG excretion increased transiently with chemotherapy, and this fluctuation was significant irrespective of the disorder (P<0.05). Interestingly, lymphoma patients with high LDH, advanced stage, poor performance status or International Prognostic Index (IPI) of high/high-intermediate risk had significantly elevated urinary 8-OHdG levels (P<0.05-<0.001). These latter results suggest that urinary 8-OHdG may be a reliable prognostic marker in lymphoma patients and should encourage large scale and long term follow up studies.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2000

Diplopia after cataract surgery.

PURPOSE: To evaluate the cause of diplopia after cataract surgery. SETTING: Cataract surgery at 7 hospitals and examination of diplopia at a central eye hospital. METHODS: This study comprised 18 eyes of 17 patients with diplopia that developed after cataract surgery in which retrobulbar anesthesia was used. The Hess screen test was done to diagnose oculomotor dysfunction. RESULTS: Several cases showed superior or inferior deviation of the globe, but most patients had nonuniform disturbances of eye movement. Examination of 3 patients by the Hess chart within 1 week after surgery showed paralysis of eye muscles but an overaction at a later stage, evident by reversal of eye position 1 month later. Surgery for strabismus was performed in 6 cases. One case with diplopia improved spontaneously 3 months after cataract surgery and achieved good alignment. CONCLUSIONS: The Hess screen test was useful for comparing changes in oculomotor function before and after surgery. Oculomotor dysfunction after cataract surgery may be caused directly by traumatic injury during administration of anesthesia or surgery using bridle sutures or indirectly from sensitivity to anesthetic agents.

Aged↗
PubMed2000

Distribution of (76)Br-labeled antisense oligonucleotides of different length determined ex vivo in rats.

Oligonucleotides may hybridize with high selectivity to an RNA sequence and can be used for the monitoring of gene expression or for its inhibition in experimental or therapeutic purposes. As part of the development of positron emission tomography (PET) methods, different lengths (30, 20, 12 and 6 mer) of antisense phosphorothioate oligonucleotides complementary to rat chromogranin A were labeled with [(76)Br] using a prosthetic group. The (76)Br-oligonucleotides were injected into rat's tail vein (1-2 MBq/rat), and the radioactivity distribution was analyzed after 20 h using whole body autoradiography or by measurement of organ radioactivity concentration. The whole body autoradiography showed different distribution depending on the oligonucleotide length. The organs with highest uptake changed from kidney cortex (with 6 or 12 mer), kidney cortex and liver (with 20 mer), to liver and spleen (with 30 mer). With 20 or 30 mer sequences, uptake could be observed in the adrenals. Kidneys and livers from rats receiving 20 mer or 30 mer (76)Br-oligonucleotides were analyzed with respect to subcellular distribution and DNA/RNA/protein fraction. 30%-45% of the radioactivity was found in the nuclear fraction. More than 80% of the radioactivity was recovered in the high molecular weight fraction (as proteins or oligonucleotides longer than 10 mer) using size exclusion (NAP 5) gelfiltration or cetylpyridinium bromide (CPB) precipitation. This work indicates the potential to perform kinetic whole body studies of (76)Br-oligonucleotides using PET.

Animals↗
PubMed2000

Diagnostic imaging with newly developed ortho cubic super-high resolution computed tomography (Ortho-CT).

OBJECTIVE: Ortho cubic super-high resolution computed tomography (Ortho-CT), which we have developed, is characterized by the small size of the unit and the ability to produce 3-dimensional images of high resolution with low-radiation doses. The purpose of this study was to investigate the clinical usefulness of Ortho-CT for the diagnosis of diseases in the oral and maxillofacial region. STUDY DESIGN: Ortho-CT has been used for the imaging diagnosis of a radicular cyst of the upper first molar, mesiodense, tooth fractures in the upper anterior region, a fracture of the condylar process, or presurgical evaluation for a dental implant. The usefulness of 3-dimensional images obtained by Ortho-CT was investigated in this study. RESULTS: Ortho-CT produced images of high resolution, enabling identification of the extent of the lesions and the fracture line, the condition of the impacted tooth, and the relationship with the maxillary sinus, mandibular canal, and adjacent teeth. CONCLUSION: Because Ortho-CT can take high-resolution 3-dimensional images at any tomographic layer with only 1 exposure, it is useful for the diagnosis of diseases in the oral and maxillofacial region.

Adult↗
PubMed2000

A 5-day course of oral desensitization to trimethoprim/sulfamethoxazole (T/S) in patients with human immunodeficiency virus type-1 infection who were previously intolerant to T/S.

BACKGROUND: Trimethoprim/sulfamethoxazole (T/S) is an essential drug in patients with human immunodeficiency virus type-1 (HIV-1) infection to prevent opportunistic infections. About 40% to 60% of them develop skin rash which leads to discontinue the medication. A precise mechanism of the reaction is not known. OBJECTIVE: To make the patients more tolerable to the medication and to make clear whether or not the reaction is caused by serum sulfamethoxazole-specific IgE. METHODS: We established a 5-day protocol, in which T/S was administered orally as a granular form in increasing doses beginning with 0.005 g (it contains trimethoprim 0.4 mg and sulfamethoxazole 2 mg) and doubled every 12 hours until the therapeutic dose was achieved. We tried to desensitize T/S in 17 patients with HIV-1 infection who were previously intolerant to T/S and measured the specific IgE in sera. RESULTS: Desensitization was successfully completed in 15 (88.2%) of the patients. In two patients who failed the desensitization, one was due to fever and the other was gastric irritation. During followup in a mean period of 16.6 months (range, 8 to 23 months) as of May, 1999, none has had Pneumocystis carinii pneumonia (PCP) while receiving T/S after desensitization. Sulfamethoxazole-specific IgE did not increase, indicating that it was not the major cause of skin rash due to T/S in our cases. CONCLUSION: These preliminary results show that most patients who were thought to be intolerant to T/S and had no sulfamethoxazole-specific IgE can be safely desensitized and received the drug subsequently as an effective prophylaxis for PCP.

Administration, Oral↗