Biomedical subjects

R Ogawa

Publications and source records attributed to R Ogawa.

At least 163 records · Page 9Linked to original sources

PubMed1995

A sex reversal infant with XX karyotype and complete male external genitalia.

The unusual case of a Japanese newborn XX male is presented. Examination of chromosomes in amniotic fluid cells had shown a normal female karyotype (46,XX), but ultrasonography revealed a penis and a scrotum. The neonate had normal male external genitalia, and serum levels of luteinizing hormone, follicle stimulating hormone, and testosterone were all within the normal range. High resonance chromosome analysis revealed an excess portion on the short arm of one of the X chromosomes. We examined his genomic DNA by polymerase chain reaction (PCR) and detected two Y specific regions in his genomic DNA, the sex-determining region Y (SRY) and pseudoautosomal boundary Y. Nucleotide sequencing of the PCR products of SRY indicated no mutation. These findings suggested that the translocation or insertion of an SRY region on the X chromosome led to the development of testicles and a male phenotype.

Base Sequence↗

PubMed1995

Hypothalamic neuronal histamine modulates physiological responses induced by interleukin-1 beta.

Dynamic involvement of hypothalamic histamine in ingestive behavior and thermogenesis induced by interleukin-1 beta (IL-1 beta) was examined in rats. Intraperitoneal injection of 0.12 nmol/rat IL-1 beta decreased food and water intake and elevated body temperature. However, depletion of neuronal histamine induced by intraperitoneal injection of 160 mumol/rat alpha-fluoromethylhistidine, a suicide inhibitor of histidine decarboxylase (HDC), attenuated the suppressive effect of IL-1 beta on food intake, facilitated the suppressive effect on drinking, and enhanced the elevating effect on rectal temperature. Intraperitoneal injection of 0.12 nmol/rat IL-1 beta increased hypothalamic histamine turnover rate. The same dose of IL-1 beta also increased activity of HDC and histamine-N-methyltransferase (HMT). These results suggest that IL-1 beta may stimulate synthesis and release of hypothalamic histamine in presynaptic terminals by activation of HDC and facilitate degradation of extracellular histamine by activation of MHT. These changes in the dynamics of hypothalamic histamine modulate IL-1 beta-induced ingestive behavior and body temperature.

Animals↗

PubMed1995

[A case of using continuous double-tapped epidural analgesia for herpes zoster duplex].

A 66-year-old woman developed herpes zoster duplex, which is a rare disease. She had severe pain at the right upper back area and left lower abdominal area. The authors used double-tapped continuous epidural analgesia for this patient. The catheters for the epidural block were placed at the 8th thoracic vertebral level and 2nd lumbar vertebral level. After the start of continuous epidural block, she suffered from nausea, vomited, and felt dizzy. It was evident that these symptoms were caused by local anesthetic toxicity. We emphasize that we must pay attention to the patient who undergoes continuous double-tapped epidural analgesia for pain relief so as not to elicit local anesthetic toxicity.

Aged↗

PubMed1995

[Investigation of Cryptomeria japonica pollinosis in Izu-Oshima].

We surveyed by questionnaire 4,673 residents of Izu-Oshima who were 15 or more years of age with regard to Cryptomeria japonica pollinosis. The response rate was 22.3%. In the early spring, nasal symptoms were reported by 8.9% of the respondents, ocular symptoms by 5.7%, and dermal symptoms by 8.1%. On scratch tests of symptomatic subjects, 13.8% were positive for Cryptomeria japonica antigen, and 33.3% had an IgE RAST score of 2 or more. The peak Cryptomeria japonica pollen concentrations between February and April 1990 were 118/cm2 on March 7 at the Northern Clinic and 271/cm2 at the Southern Clinic. A second questionnaire survey (response rate: 53.1%), designed to estimate the number of persons with Cryptomeria japonica pollinosis among all residents, revealed that 4.7% concurrently had three or more nasal symptoms and two ocular symptoms. By combining these results with those of a telephone survey of 100 randomly selected nonrespondents, 5.64% of all inhabitants were estimated to have suspected Cryptomeria japonica pollinosis.

Adolescent↗

PubMed1995

[Endothoracic anesthesia for artificial anus formation in rabbits].

We succeeded in maintaining anesthesia for artificial anus formation in rabbits using a new anesthetic technique of endothoracic anesthesia. The drug injection through a catheter, which was inserted into the endothoracic fascia at the level of the 11th thoracic vertebra, caused an unilateral anesthesia from the chest down to the lower limb. Artificial anus formation was possible by this endothoracic anesthesia with a help of medetomidine and nitrous oxide.

Anesthesia, Local↗

PubMed1995

[Successful treatment of acute myelomonocytic leukemia developed from MDS with cytarabine ocfosfate (SPAC)].

A 65-year-old female with acute myelomonocytic leukemia (AMMoL) developed from myelodysplastic syndrome (MDS), successfully treated with cytarabine ocfosfate (SPAC) is reported. Ubenimex, calcitriol and corticosteroid had a minor effect on her MDS. Since she had severe anemia and congestive heart failure on developing leukemia, she was treated with oral administration of SPAC, a cytidine deaminase resistant derivative of Ara-C. After the second course of SPAC (200 mg/day, for 14-28 days), marked erythroid bursts were found and she entered complete remission. The samplings of SPAC and its metabolites of SPAC were investigated in 2 cases including this case, but there seemed to be no relation between their content and effects. In AML patients, especially in cases developed from MDS, SPAC might be useful because it can be given orally even in an outpatient.

Aged↗

PubMed1995

[Semiselective renal and lumbar angiography: experimental and clinical evaluation of this new angiographic method].

In conventional aortography, all branches of the aorta may be visible, making interpretation difficult. By a new angiographic method, only the dorsal and lateral branches of the aorta are made visible, without the appearance of ventral branches such as the celiac, superior mesenteric, and inferior mesenteric arteries. The contrast medium is injected slowly through a closed-end catheter with side holes arranged on one side only. The best conditions for such angiography were as follows: a catheter with five side holes (the two proximal holes were small) with neighboring holes 3 cm apart, injection of 12 ml of contrast medium at the rate of 4 ml/second, and the catheter placed next to the dorsal wall of the aorta. The catheter could be held in this position when the aorta was curved provided that the head of the catheter was spiral and the next portion was convex. In clinical angiography, 24 patients suspected to have retroperitoneal or spinal disease were examined. The dorsal branches of the aorta were seen but the ventral branches were not seen in 19 of the patients. This method was superior to conventional aortography for the evaluation of lumbar arteries and the main trunks of renal arteries. In nine patients, the evaluation of abnormal findings such as feeding arteries was easier by this method than by conventional aortography.

Abdominal Muscles↗

PubMed1995

[The clinical usefulness and problem of combined spinal epidural needle].

The clinical usefulness of combined spinal-epidural needles, Portex Spinal/Epidural set (Pencil point tip type and Lancet point tip type), was evaluated on 30 patients undergoing orthopedic lower limb surgeries, hysterectomies or transurethral surgeries. In all the patients, the spinal-epidural needles were successfully inserted with paramedian approach without any problem. The time to appearance of cerebrospinal fluid in the spinal needle hub after removal of the stylet was 15-40 seconds, and no patient in both groups had postspinal headache. Following spinal anesthesia, the local anesthetics injected through the epidural catheter extended the analgesia in the range of 1-2 dermatomes higher in the Lancet point type group in comparison with Pencil point type group. It is possible that the hole in the dura may allow a transfer of local anesthetics into the subarachnoid space. The present study shows that combined spinal-epidural block is clinically useful, and the Pencil point type is safer than the Lancet point type.

Adult↗

PubMed1995

[Efficacy of epidural neurolysis].

Forty-one patients were treated with epidural neurolysis using 50 % ethyl alcohol 2 ml. Thirty eight patients were suffering from cancer pain and three patients were complaining of chronic benign pain. Alcohol block was repeated 2.3 times (mean) in the same patient. Thirty patients were followed after the treatment. Forty-seven percent of the patients reported 70 % or greater pain relief and 20 % of the patients reported about 50 % pain relief. Duration of pain relief was from 9 days to 203 days with a mean duration of 54 days. Adverse effects were reported 43 % of the patients. There is no miserable adverse effect. Adverse effect reported most was pain with epidural injection of drugs after the alcohol block had been performed.

Adult↗

PubMed1995

[Somatosensory evoked potentials for the diagnosis of carpal tunnel syndrome].

The middle latency somatosensory evoked potential (SEP), in particular the N60 of median nerve SEP, can be recorded in patients with severe peripheral neuropathy even in the absence of a recordable compound muscle action potential (CMAP). However, clinical utilization of N60 is hampered by its inter-trial variabilities that depend on the level of consciousness, habituation, stimulus rate and/or other unknown factors. We have now obtained a stable N60 SEP when the subject stays awake and alert using a slow stimulus rate. We have applied this method to 17 hands of 15 patients with severe carpal tunnel syndrome (CaTS) whose CMAP were not recordable. The stimuli were applied to two sites: one was 2 cm proximal to the distal crease at the wrist and the other was on the middle finger. SEP were recorded from a central electrode contralateral to the side of stimulation and referenced to the bilateral ear. In normal subjects, the estimated conduction velocities between the distal crease and the middle finger measured by the N60 latency difference ranged from 45.1 to 89.2 m/sec with a mean velocity of 67.4 +/- 13.0 m/sec. In 12 CaTS hands, the stimulation of the fingers resulted in a significantly delayed N60 (8 hands) or no response (4 hands). The estimated conduction velocity in CaTS ranged from 9.3 to 21.2 m/sec with mean velocity of 15.6 +/- 4.2 m/sec. In order to localize the point of maximal conduction delay in the CaTS, a further 17 hands were examined by stimulation of the median nerve at multiple sites across the carpal tunnel.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1995

[Electrophysiological and MRI study on poor outcome after surgery for cervical myelopathy].

Occasionally, the outcome from laminoplasty for cervical spondylosis is disappointing despite an adequate operation. Before surgery, it is difficult to diagnose the pathological extent of the involvement of the spinal cord. The purpose of this study is to determine the efficacy of magnetic resonance imaging (MRI) and of the motor evoked potentials (MEPs) for the indication of the surgery and prognosis. Retrospectively, we investigated the MEPs and the MRI image of 31 patients in surgery for cervical myelopathy, involving 21 cases with cervical spondylosis and 10 cases with ossification of the posterior longitudinal ligamentum, and compared the findings from those with a poor outcome (n = 31) with the findings from those with a good outcome (n = 32). The MEPs from the thenar muscle and the tibialis anterior were evoked by transcranial magnetic brain stimulation. In the poor-outcome patients, the spinal canal was narrow and lumbar spinal canal stenosis was seen in 5 cases which required lumbar laminectomy. Before operation, the MEPs from the thenar muscle could not be evoked in 5 cases while there was a remarkably prolonged central motor conduction time in the other 26 cases. MRI revealed the deformed spinal cord in the involved area, and the signal intensity of the involved spinal cord in the T2 weighted image was remarkable high. The signal intensity ratio was significantly higher in the poor-outcome patients than in the good-outcome patients. This study suggested that a high signal intensity in the T2 weighted image and a prolonged conduction time or absence of MEPs largely corresponded to the clinical and other investigative features of myelopathy responsible for a poor outcome.

Aged↗

PubMed1995

[MEPs by transcranical magnetic stimulation in experimental acute spinal cord injury].

The efficacy of motor evoked potentials (MEPs) induced by magnetic brain stimulation was investigated experimentally for assessing acute spinal cord injury. Twenty-five rabbits were employed for the acute spinal cord injury model. Following laminectomy under intravenous and intraperitoneal anesthesia, the spinal cord at the level of the fifth lumbar vertebra wsa injured by Allen's weight drop method. MEPs from the tibialis anterior muscle (M-MEP) were recorded using bipolar electrodes: prior to the injury; immediately after the injury; at 30 min, 1 hour, 3 hours, and at 5 hours after the injury. MEPs from the spinal cord (S-MEP) were recorded proximal to and distal from the injury site using epidural tube electrodes. Subjects were divided into two groups; complete and incomplete paralysis, according to the degree of motor dysfunction at 1 week after the injury. All the 13 subjects with incomplete paralysis had shown immediately after the trauma a prolongation in the M-MEP latency, with a polyphasic wave form seen in 5 of them. In 3 cases, the amplitude of the M-MEPs was decreased without any change in wave form. In others, there was some variation in the change of wave form, but there was no relationship found between the change of wave form and the degree of motor dysfunction in this group. Histopathologically, infiltration of the inflammatory cells and diffuse hemorrhaging were seen in the gray matter of the injured spinal cord in the incomplete paralysis group. In 7 of the 10 cases with complete paralysis, the M-MEP disappeared within 3 hours. Histopathologically, large areas of the nerve cells disappeared from the gray matter in this group. The S-MEP disappeared immediately after trauma in the group with complete paralysis as well as in those with incomplete paralysis. This study indicated that MEPs taken immediately after a trauma may predict the severity of a spinal cord injury and were useful for evaluating the prognosis of motor function during the acute phase of a spinal cord injury.

Acute Disease↗

PubMed1994

Requirement of donor-derived stromal cells in the bone marrow for successful allogeneic bone marrow transplantation. Complete prevention of recurrence of autoimmune diseases in MRL/MP-Ipr/Ipr mice by transplantation of bone marrow plus bones (stromal cells) from the same donor.

MRL/MP-Ipr/Ipr (MRL/Ipr) mice possess radioresistant (9.5 Gy) abnormal stem cells and show a recurrence of autoimmune diseases within 5 mo of conventional allogeneic bone marrow transplantation. We recently have found that the MHC preference exists between hemopoietic stem cells and stromal cells; when bones are engrafted, donor-derived stromal cells present in the engrafted bones can migrate into the recipient bone marrows, which are replaced with both donor-derived stromal cells and hematopoietic cells. Based on these findings, we attempted to prevent the recurrence of autoimmune diseases in MRL/Ipr mice by the transplantation of both bone marrow cells and bone (as a source of stromal cells). MRL/Ipr mice were irradiated (8.5 Gy) and then reconstituted with C57BL/6 bone marrow cells plus bone grafts. The mice survived more than 48 wk after this treatment. Immunohistologic studies revealed that the mice were completely free from both lymphadenopathy and autoimmune diseases such as lupus nephritis and rheumatoid arthritis. Sera from these mice showed normal levels of circulating immune complexes and rheumatoid factors. Normal functions of both T cells and B cells were noted. Abnormal T cells such as Thy-1+B220+ cells present in nontreated MRL/Ipr mice could not be seen in the thus-treated mice. In addition, to our surprise, spleen cells from treated mice showed completely normal in vitro primary anti-SRBC responses. These results indicate that stromal cells in allogeneic bone marrow transplantation play a crucial role not only in the prevention of graft failure but also in the successful cooperation among APCs, T cells, and B cells. Although MRL/Ipr mice are radiosensitive and usually die of interstitial pneumonia or fatty liver due to the side effects of radiation, it should be noted that this strategy allows a reduction in the radiation dose (9.5 Gy-->8.5 Gy), and that these mice can survive more than 48 wk without showing any symptoms of autoimmune diseases.

Animals↗

PubMed1994

Thermoregulation and hypothalamic histamine turnover modulated by interleukin-1 beta in rats.

To clarify the involvement of hypothalamic histamine in thermogenic response provoked by high ambient temperature, or interleukin-1 beta (IL-1 beta), changes in rectal temperature and histamine turnover were investigated. Rectal temperature was maintained normally after exposure to high ambient temperature, but elevated by IL-1 beta. In spite of these different responses of body temperature, hypothalamic histamine turnover was increased in each treatment. The results suggest that hypothalamic histaminergic neurons are activated not only peripherally by high ambient temperature, but also centrally by IL-1 beta as endogenous pyrogen.

Animals↗

PubMed1994

In vivo experimental analysis of silicone implants used with titanium grommets.

This study evaluated the titanium grommets recommended to reduce breakage by protecting hinge implants from bone edges. Silastic HP-100 (Dow Corning Wright, Arlington, TN) flexible finger implants (size 5) were used to replace one knee of 10 rabbits, and implants plus titanium grommets were used in another 10. X-ray films were taken monthly; deaths from each group were 1 animal at 2 and 4 months, 2 animals at 6, and 3 each at 12 and 16 months. X-ray films revealed that 4 of 10 implants from each group had fractured. Silicone fractures occurred identically at the proximal stem-hinge junction in both groups, destruction was always most pronounced at the dorsal surface of the proximal stems. The time from surgery to x-ray film evidence of implant fracture without grommets was an average of 9 months and with grommets 13 months. Although grommets delayed x-ray film evidence of fracture onset, after 14 months all implants in both groups of animals fractured. These findings do not support the hypothesis that grommets prevent silicone hinge implant wear or fracture in this experimental model.

Animals↗

PubMed1994

In vivo experimental analysis of silicone implants on bone and soft tissue.

We report experimentally produced silicone microparticles (synovitis) in 47 white rabbits and discuss the implications for clinical practice. Silastic HP100 (Dow Corning Wright, Arlington, TN) finger hinges (size 5) were inserted in 20 rabbit's knees. The upper tibia was replaced with Swanson design great toe implants in another 15 rabbits; articular cartilage was removed and endosteal drilling was performed in 6 animals as a "sham" arthroplasty. Small silicone blocks were inserted in the proximal tibial endosteal canal of 6 others. Animals were followed by monthly x-ray films and killed at 2, 4, 6, 12, and 16 months. Implant wear, bone surfaces, and soft tissue were examined under the operating microscope and by light microscopy; implant surfaces were examined with scanning electron microscopy. X-ray changes included reactive endosteal bone formation around implant stems as early as 1 month postoperatively; at 2-3 months the new bone line was clearest but it became progressively homogeneous and less evident. Extensive cortical erosion around the stems was observed in one third of the animals. Neither ossification nor lysis was observed around the silicone block. Proliferative synovitis was found at post-mortem examination beginning after 4 months; femoral condylar erosions were observed in most animals after 12 months. Wherever there was bone destruction, silicone particles were confirmed by x-ray spectrography.

Animals↗

PubMed1994

Age-related changes in fibre number, fibre size, fibre type composition and adenosine triphosphatase activity in rat soleus muscle.

To study the aging of muscle fibres in red skeletal muscle, fibre number, fibre diameter and fibre type composition in the soleus muscle of male rats of 3, 12 and 24 months old were examined. The total number of muscle fibres remained unchanged, while average diameter increased slightly with increasing age. The staining intensity of myosin adenosine triphosphatase (ATPase) activity in the fibres decreased with advancing age. Therefore, observation on the basis of myosin ATPase histochemistry alone is not adequate to study the aging of muscle fibres. In the muscles of 24 month-old animals, four fibre types were recognized; 1) many (52%) type I-O fibres showing weak ATPase and succinate dehydrogenase (SDH) reactions with slight subsarcolemmal aggregates of diformazan (SAD); 2) some (33%) type M fibres showing weak ATPase and intense SDH reactions with marked SAD; 3) a few (12%) type O fibres showing weak ATPase and intense SDH reactions without SAD; and 4) very few (4%) type IIA fibres. Histochemical and morphometric results suggest that type I-O, type M and type O fibres are derived from type I, type I and type IIA fibres, respectively. Furthermore, no transitional fibres from type IIA to type I were observed. Therefore, age-related changes in fibre type composition in the muscle cannot be explained by the simple idea that most type IIA fibres are transformed into type I fibres.

Aging↗

PubMed1994

Pressure gradients between intraluminal and extraluminal spaces may affect the potassium induced contraction in the rabbit's basilar arteries.

In order to investigate the different contactile effects between intraluminal and extraluminal vasoactive agents, we studied the contractile responses of rabbit basilar artery to selective intraluminal and extraluminal administration of potassium, serotonin and histamine in vitro. We also studied how the physical pressure gradients, such as hydrostatic or osmotic pressure gradients between intraluminal and extraluminal spaces, affect potassium-induced contraction. Intraluminal potassium (30 mM) induced a significantly greater contraction than extraluminal potassium. Serotonin (2 x 10(-7) M) and histamine (10(-5) M) applied intraluminally caused the same magnitude of the contraction as those applied extraluminally and no significant differences were noted between these applications. These differences in potassium-induced contraction were more significant when the intraluminal hydrostatic pressure was elevated by 20 mmHg. Contraction by either intraluminal or extraluminal potassium was significantly decreased when intraluminal pressure was raised by 40 mmHg. As the osmotic pressure gradients between the extraluminal and the intraluminal spaces were increased, these differences in potassium-induced contraction were decreased. Our findings suggest that physical pressure gradients may affect potassium-induced contraction in a different manner from pharmacologically-induced contraction and that free ions can penetrate the vascular wall by physical pressure gradients between the intraluminal and extraluminal spaces of cerebral artery.

Animals↗