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Biomedical subjects

S Fukuda

Publications and source records attributed to S Fukuda.

At least 379 records · Page 21Linked to original sources
PubMed1996

Validity of various diagnostic tests to evaluate cure of Helicobacter pylori infection.

Many diagnostic methods have been developed and used for detecting Helicobacter pylori to evaluate the success of treatment of H. pylori infection. We investigated and compared the suitability of the rapid urease test (RUT), polymerase chain reaction (PCR), 13C-urea breath test (13C-UBT), and serology with culture for evaluating cure of H. pylori infection. Forty-seven H. pylori-positive gastric ulcer patients received dual therapy of lansoprazole (30 mg u.i.d.) and clarithromycin (200 mg b.i.d.). Four weeks after the completion of treatment, RUT, PCR, 13C-UBT, and culture were performed and the negative rates of these tests were compared. Anti-H. pylori IgG antibodies were measured by enzyme-linked immunosorbent assay (ELISA) before and 4 weeks after completion of the treatment to evaluate changes of titers during the treatment. The negative rate of RUT (55%) was significantly greater than that of culture (27%). Significant declines in titers were seen in the patients who had negative culture results, while the decline in the titer was not significant in the patients who had positive results. PCR assay and 13C-UBT were suitable for the evaluation of H. pylori eradication, but RUT was not suitable, because of its sensitivity. By monitoring anti-H. pylori IgG antibody titers, therapeutic failure can be detected early after completion of treatment.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1996

Immunomodulating and articular protecting activities of a new anti-rheumatic drug, TAK-603.

We investigated the pharmacological activities of a newly synthesized anti-rheumatic drug, TAK-603. (1) In vivo: In adjuvant arthritic (AA) rats, TAK-603 inhibited the hind paw swelling and the body weight loss. The minimum effective dose was 3.13 mg/kg/day (p.o.). Histological and radiographic studies showed that TAK-603 suppressed the development of synovial lesions and joint and bone destruction. TAK-603 was also effective in AA rats when administered for the first 7 days after the adjuvant injection. It suppressed type IV allergy (25 mg/kg/day, p.o.) but had no effect on type III allergy. It had little effect in acute inflammation, analgesic and antipyretic models. These data suggest that TAK-603 acts on the immune system, especially on cellular immunity. (2) In vitro: TAK-603 suppressed the mitogen-induced proliferation of mouse lymphocytes and the ConA-induced IFN-gamma and IL-2 production by rat lymphocytes at 10(-7) to 10(-5) M. It also significantly inhibited the IL-1 induced extracellular matrix reduction in rabbit chondrocytes. It had no effects on prostaglandin E2 (PGE2) production in rat peritoneal cells. These data show that TAK-603 has the ability to suppress the immune system and protect cartilage from destruction. TAK-603 is expected to be a promising drug for rheumatoid arthritis.

Adjuvants, Immunologic↗
PubMed1996

RANTES production in nasal epithelial cells and endothelial cells.

BACKGROUND: It is well documented that the chemokine that is regulated upon activation, normal T expressed and presumably secreted, RANTES, is produced by macrophages, platelets, fibroblasts, and renal tubular epithelial cells. Recently, however, production of RANTES by vascular endothelium and airway epithelial cells was demonstrated in human umbilical vein endothelial cells (HUVECs) and epithelial cell lines. OBJECTIVE: This investigation was aimed at determining whether human nasal epithelial cells (HNECs) and human mucosal microvascular endothelial cells (HMMECs) produce RANTES when they are stimulated by several cytokines. METHODS: HNECs and HMMECs were isolated from nasal mucosa and subsequent continuous subcultures and were stimulated either by IL-1 beta or by the combination of tumor necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma). RESULTS: After the combined stimulation by TNF-alpha and IFN-gamma, HNECs and HMMECs dramatically produced RANTES, as previously observed in HUVECs and bronchial epithelial cell line BEAS-2B. IL-1 beta also increased RANTES production to a lesser extent. We also demonstrated that the amount of RANTES induced by TNF-alpha and IFN-gamma was higher in HNECs and HMMECs obtained from patients with nasal allergy than in those from patients without allergy. CONCLUSION: RANTES from HNECs and HMMECs likely plays a critical role in eosinophil infiltration of the nasal mucosa in subjects with nasal allergy.

Adolescent↗
PubMed1996

Somatosensory evoked potentials recorded from the posterior pharynx to stimulation of the median nerve and cauda equina.

Somatosensory evoked potentials (ppSEPs) in response to stimulation of the median nerve at the wrist and the cauda equina at the epidural space (the L4 level) were recorded from the posterior wall of the pharynx in 15 patients who underwent spinal surgery under general anesthesia, using disc electrodes attached to the endotracheal tube, and compared with segmental spinal cord potentials (seg-SCPs) that were recorded simultaneously from the posterior epidural space (PES). ppSEPs consisted of the initially positive spike (P9) followed by slow positive (P13) and negative (N22) waves. The P13 and N22 of ppSEPs had phase reversal relationship with the P2 and N2 recorded from the PES, respectively. The peak latencies of P9 (9.40 +/- 0.7 ms) (mean +/- SD), P13 (13.1 +/- 0.9 ms), and N22 (22.0 +/- 2.1 ms) of ppSEPs coincided with those of P1, N1 and P2 of seg-SCPs, respectively, ppSEPs were recorded more clearly with a reference electrode on the dorsal surface of the neck than with the reference electrode at the earlobe or back of the hand. The threshold and maximal stimulus intensities were also similar between the ppSEPs and seg-SCPs. Thus, the P9, P13, and N22 components of ppSEPs were thought to have the same origin as the P1, N1 and P2 of seg-SCPs, respectively. Therefore, the P9, P13 and N22 of ppSEPs may reflect incoming volleys through the root, synchronized activities of the interneurons and primary afferent depolarizations (PAD), respectively. ppSEPs in response to cauda equina stimulation showed that the latencies of the two initial components (4.6 +/- 0.4 and 6.4 +/- 0.6 ms) corresponded to those of the SCPs recorded from the PES (4.6 +/- 0.3 and 6.3 +/- 0.5 ms), suggesting that these potentials reflect impulses conducting through the spinal cord, similar to epidurally recorded SCPs.

Adult↗
PubMed1996

Gastroepiploic artery graft in 400 patients.

The right gastroepoploic artery (GEA) has been used for coronary artery bypass grafting (CABG) in 400 patients of a total of 1359 undergoing the same procedure during an 8-year period. There were 327 males and 73 females with a mean age of 59 years. Single-, double- and triple-vessel and left main disease were noted in 4, 51, 283 and 62 patients, respectively. Previous myocardial infarction was noted in 208 patients and 40 patients had undergone previous CABG. Internal thoracic artery (ITA) and inferior epigastric artery grafts were concomitantly used in 388 (97%) and 30 (8%) patients, respectively. The mean number of grafts was 3.2 including vein grafts, and 2.3 coronary arteries were bypassed with arterial grafts. The sites of GEA grafting were 43 anterior descending, 6 diagonal, 71 circumflex, and 287 right coronary arteries with 376 in situ and 24 free grafts including 7 sequential grafts. There were eight (2%) early and five (1.3%) late deaths. New Q waves were noted in six (1.5%) patients. Warm body circulation is thought to be favorable with a lower incidence of the need for intra-aortic balloon pump (0.6% vs 6.0%). Postoperative angiography revealed 94% (253/268) early (2 months) and 94% (47/50) late (2-5 years) patency of GEA grafts. In conclusion. GEA is a safe and effective arterial conduit for CABG.

Abdominal Muscles↗
PubMed1996

Interferon-gamma enhances megakaryocyte colony-stimulating activity in murine bone marrow cells.

We have demonstrated previously that interferon-gamma (IFN-gamma) accelerates platelet recovery in mice with 5-FU induced-marrow aplasia in vivo. However, the mechanism for the regulation of megakaryocyte development induced by IFN-gamma in bone marrow cells in vivo remains unknown. To further study the effects of IFN-gamma on megakaryocyte development, various steps during IFN-gamma-mediated accelerated differentiation of the megakaryocytes were investigated in serum-free cultures of murine bone marrow cells in vitro. IFN-gamma markedly induced acetylcholine esterase (AChE) activity, a marker of murine megakaryocytic cells, accompanied by increased colony formation of the megakaryocyte lineage. A prominent increase in megakaryocyte number was observed after IFN-gamma treatment. All of these effects were dependent on the presence of IL-3, and, therefore, these results suggest that IFN-gamma acts as a megakaryocyte potentiator (Meg-POT). However, IFN-gamma did not enhance megakaryocyte maturation with respect to increase in cell size. The effects of IFN-gamma on megakaryocyte maturation were similar to those observed after treatment with higher doses of IL-3 alone. Meg-POT is defined as a factor that induces megakaryocyte maturation. Since IFN-gamma enhanced IL-3-dependent megakaryocyte colony formation and proliferation rather than megakaryocyte maturation, the effects on megakaryocyte development, which were induced by IFN-gamma treatment, seem to be different from the effects of a Meg-POT. We, therefore, propose a new function for IFN-gamma as an enhancer of megakaryocyte colony-stimulating factor activity. The effect of IFN-gamma in vitro appears to correlate well with the acceleration of platelet recovery in vivo.

Acetylcholinesterase↗
PubMed1996

Central nuclei and spinal pathways in feedback inhibitory spinal cord potentials in ketamine-anaesthetized rats.

It has been suggested that heterosegmentally activated slow positive potentials (HSP), recorded from the spinal cord of rat and humans, are feedback inhibitory potentials. The present study was carried out to define ascending and descending spinal tracts and the sites of central nuclei involved in the production of these HSP, and the effects of ketamine on these central nuclei. The spinal cords in ketamine-anaesthetized rats were transected to determine the ascending and descending tracts involved in the production of hindpaw (HP) and forepaw (FP) HSP, respectively. Lesions of the brain at various levels were performed stereotactically during ketamine anaesthesia. Dorsal one-third resection of the cord at the T8-9 level did not affect HSP significantly, while contralateral lesion of the dorsal two-thirds of the cord decreased FP-HSP but not HP-HSP during ketamine. Bilateral transection of the ventral one-third of the cord abolished both HSP. Ablation of the cerebral cortex, cerebellum, thalamus, midbrain and pons did not affect HSP significantly. However, transection of the middle medulla decreased, while transection of the most caudal part of the medulla completely abolished both HSP. Ketamine decreased HSP even in the medulla-spinal cord preparation and the segmental slow positive wave in spinalized animals. In ketamine-anaesthetized rats, ascending and descending spinal tracts involved in the production of HP-HSP and FP-HSP are located bilaterally in the ventrolateral quadrant and in the contralateral lateral funiculus and ventrolateral quadrant, respectively. Principal central nuclei feeding back HSP might be situated diffusely in the medulla down to the caudal part. Ketamine is suggested to suppress these inhibitory feedback potentials predominantly at, and partly even below, the level of the medulla.

Anesthetics, Dissociative↗
PubMed1996

The effects of halothane on arginine-vasopressin-induced Ca2+ mobilization from the intracellular stores and the receptor-mediated Ca2+ entry from the extracellular space in single cultured smooth muscle cells of rat aorta.

Halothane has a direct action on vascular smooth muscle cells and causes relaxation of these cells, yet neither the mechanism nor the site of its action is completely understood. Using digital imaging microscopy with the Ca2+ indicator fura-2, the effects of halothane on the intracellular [Ca2+] dynamics induced by arginine vasopressin (AVP) in the perinuclear region and cytosol in single cultured smooth muscle cells of rat aorta were studied. Changes in intracellular [Ca2+] were expressed as percent increases in the ratios of fluorescence intensity at 500 nm excited by 340 nm and 380 nm. AVP (10(-7) M) elicited an initial transient increase in [Ca2+] in the perinuclear region higher than that in the cytosol in Ca(2+)-containing solution (346% +/- 21% and 213% +/- 22%, respectively). Halothane, 0.5%, attenuated the [Ca2+] increase induced by AVP in the perinuclear region and cytosol, and halothane, 1.0% and 2.0%, abolished the differential increase. Under the continuous application of AVP (10(-7) M), Ca2+ restoration in the medium after perfusion with Ca(2+)-free solution increased the perinuclear [Ca2+] more than the cytosolic [Ca2+]. Both were significantly attenuated by 2.0% halothane, but not by nicardipine (10(-5) M) or ryanodine (10(-6) M). Our results suggest that halothane may attenuate the Ca2+ release from the intracellular Ca2+ stores more than the receptor-mediated Ca2+ entry from the extracellular space in the AVP-induced response in these cells.

Anesthetics, Inhalation↗
PubMed1996

Purification and characterization of thermostable maltooligosyl trehalose synthase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius.

A thermostable maltooligosyl trehalose synthase was purified from a cell-free extract of the thermoacidophilic archaebacterium Sulfolobus acidocaldarius ATCC 33909 to an electrophoretically homogeneous state by successive column chromatography on Sepabeads FP-DA13, Butyl-Toyopearl 650M, DEAE-Toyopearl 650S, Ultrogel AcA44, and Mono Q. The enzyme had a molecular mass of 74,000 by SDS-polyacrylamide gel electrophoresis and a pI of 5.9 by gel isoelectrofocusing. The N-terminal amino acid of the enzyme was methionine. The enzyme showed the highest activity from pH 5.0 to 5.5 and at 75 degrees C, and was stable from pH 4.5 to 9.5 and up to 85 degrees C. The enzyme activity was inhibited by Hg2+ and Cu2+. The Kms of the enzyme for maltotetraose, maltopentaose, maltohexaose, maltoheptaose, and short chain amylose (DP 18) were 41.5 mM, 7.1 mM, 5.7 mM, 1.4 mM, and 0.6 mM, respectively.

Amino Acid Sequence↗
PubMed1996

Purification and characterization of thermostable maltooligosyl trehalose trehalohydrolase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius.

A thermostable maltooligosyl trehalose trehalohydrolase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius ATCC 33909 was purified from a cell-free extract to an electrophoretically pure state by successive column chromatographies on Sepabeads FP-DA13, Butyl-Toyopearl 650M, DEAE-Toyopearl 650S, Toyopearl HW-55S and Ultrogel AcA44. The enzyme had a molecular mass of 59,000 by SDS-polyacrylamide gel electrophoresis and a pI of 6.1 by gel isoelectrofocusing. The N-terminal amino acid of the enzyme was methionine. The enzyme showed the highest activity from pH 5.5 to 6.0 and at 75 degrees C, and was stable from pH 5.5 to 9.5 and up to 85 degrees C. The activity was inhibited by Hg2+, Cu2+, Fe2+, Pb2+, and Zn2+. The Km values of the enzyme for maltosyl trehalose, maltotriosyl trehalose, maltotetraosyl trehalose, and maltopentaosyl trehalose were 16.7 mM, 2.7 mM, 3.7 mM, and 4.9 mM, respectively.

Chemical Phenomena↗
PubMed1996

Purification and properties of a novel enzyme, trehalose synthase, from Pimelobacter sp. R48.

A novel enzyme, trehalose synthase, was purified from a cell-free extract of Pimelobacter sp. R48 to an electrophoretically homogeneous state by successive chromatographies on DEAE-Toyopearl 650, Butyl-Toyopearl 650, and Mono Q HR5/5 columns. The molecular weight of the enzyme was estimated to be 62,000 by SDS-polyacrylamide gel electrophoresis, and the enzyme had a pI of 4.6 by gel isoelectrofocusing. The enzyme catalyzed the conversion of maltose into trehalose by intramolecular transglucosylation. The enzyme also converted into maltose but was inactive on other saccharides. The N-terminal amino acid of the enzyme was serine. The optimum pH and temperature were pH7.5 and 20 degrees C, respectively. The enzyme was stable in the range of pH 6.0-9.0 and up to 30 degrees C for 60 min. The rate of conversion of maltose into trehalose was independent of the maltose concentration. The maximum yield of trehalose from maltose were 81.8%, 80.9%, and 76.7% at 5, 15, and 25 degrees C, respectively. The activity was inhibited by Cu2+, Hg2+, Ni2+, Zn2+, and Tris.

Amino Acid Sequence↗
PubMed1996

Mineral metabolism in plasma, urine and bone of periparturient cows fed anionic diets with different calcium and phosphorous contents.

The objective of this experiment was to evaluate the influences of Ca and P contents in an anionic diet on the mineral metabolism in plasma, urine and bone in periparturient diary cows. Fifteen multiparous Holstein-Friesian cows were divided into 3 dietary groups (5 cows/group) by dietary Ca and P contents and dietary cation-anion balance [(Na + K) - (Cl + S) mEq/kg DM]; diet 1 [low Ca (0.46%), low P (0.24%), cationic (+195.8 mEq/kg DM)]; diet 2 [low Ca (0.46%), low P (0.24%), anionic (-32.4 mEq/kg DM)]; and diet 3 [high Ca (0.93%), high P (0.60%), anionic (-41.0 mEq/kg DM)]. Cows were fed one of these 3 diets from approximately 4 weeks before the expected calving date to 5 days after calving. There was no outbreak of milk fever in any cows fed these 3 diets; however, plasma Ca levels at 1 and 2 days after calving tended to be higher in the cows fed diet 3 than those in the cows fed diets 1 or 2. Fractional urinary excretion of Ca in the cows fed diet 2 or 3 was higher than that in the cows fed diet 1. Fractional urinary excretion and plasma level of Pi were higher during the periparturient period in the cows fed diet 3 than those in the cows fed diets 1 or 2. There were no significant differences in plasma parathyroid hormone levels among the 3 groups. In the spongy substance of ilium at 5 days after calving, the Ca and Mg contents bone volume and trabecular thickness were the lowest, but not significant, in the cows fed diet 2. These data suggest that sufficient Ca and P contents in an anionic diet may be effective in maintaining plasma Ca and Pi levels of periparturient cows and further in preventing of potential bone damage brought about by increased urinary mineral excretion following the feeding of an anionic diet.

Animal Feed↗
PubMed1996

Experimental studies on bovine Hyena disease induced by administration of excessive vitamin AD3E premix, vitamin A, or vitamin D3.

The effects of the excessive administration of the vitamin AD3E(V-AD3E) premix, vitamin A (V-A) or vitamin D3 (V-D3) on experimental development of Hyena disease in the calves were examined. Hyena disease was recognized in 4 calves, both of the 2 calves administered a high dose of V-AD3E premix (V-A 3,000,000, V-D3 300,000, and V-E 1,200 IU/day, V-AD3E group), 1 of the 2 calves administered a half dose of the V-AD3E premix, and 1 of the 2 calves administered only V-A (V-A 3,000,000 IU/day, V-A group) when each vitamin was administered orally for 10 days from 1 week after birth. Both of 2 calves administered only V-D3 (V-D3 300,000 IU/day) did not developed. In the 4 calves with Hyena disease (Hyena calves), the plasma retinylpalmitate showed high values which was suggesting the hypervitaminosis A, and the epiphysial growth plate was narrow and destroyed structure of column. Compared with the Hyena calf in the V-A group, the Hyena calves in the V-AD3E group showed earlier appearance time of Hyena disease, lower growth rate and shorter lengths of fore and hind limb bones. In conclusion, the present findings suggested that excessive V-A administration to suckling calves might cause Hyena disease by V-A effects to the epiphysial growth plate, moreover such effects may be promoted by the V-D3.

Aging↗
PubMed1996

Changes in bone metabolism and epiphysial growth plate in bovine Hyena disease induced by administration of vitamin AD3E premix or Vitamin A.

The changes in bone metabolism and morphology of chondrocytes in bovine Hyena disease caused by administration of vitamin AD3E premix (V-AD3E) or vitamin A (V-A) were examined. At the each age, 5 calves were used. Among them, Hyena disease was recognized in 3 calves; a calf administered a high dose of V-AD3E premix (V-A 3,000,000, V-D3 300,000, and V-E 1,200 I.U./day), a calf administered a half dose of the V-AD3E premix, and a calf administered only V-A 3,000,000 I.U./day. The remaining calves without Hyena disease were a calf administered only V-D3 300,000 I.U./day and a control calf. Each agent was administered orally for 10 days from 1 week after birth. In the 3 calves with Hyena disease, the bone metabolism in bone histomorphometry of ilium was in the state of low turnover at the age of 50 days. The bone volume was small at the age of 12 months. The epiphysial growth plates of the distal femurs and the proximal tibias partially disappeared and the chondrocyte lacunas in them were flattened. The matrix fibers of epiphysial growth plates were thinner in diameter and higher in density than those of the control calf. In the calf administered only V-D3, the values of bone volume decreased with aging. In conclusion, Hyena disease may be caused by excessive administration of V-A, because hypervitaminosis A suppressed the activity of differentiation and proliferation in chondrocytes and osteoblasts, and excessive administration of V-D3 may promote these actions.

Animals↗
PubMed1996

Bone histomorphometric changes due to differences in calcium intake under metabolic acidosis in rats.

Effects of differences in calcium (Ca) intake on bone metabolism under metabolic acidosis were examined by bone histomorphometry in rats. Rats were divided into 5 diets; low Ca (0.02%) diet (LCD), moderate low Ca (0.3%) diet (LmCD), standard Ca (0.62%) diet (SCD), moderate high Ca (1%) diet (HmCD) and high Ca (3%) diet (HCD). Each diet rats were subdivided into the acidotic group given a 1.8% ammonium chloride solution as drinking water and control group given deionized water. Blood and double labeled bone were collected 30 days later. Arterial blood pH was significantly lower, and plasma ionized Ca level and urinary Ca excretion were higher in the acidotic groups than those in the control groups in all diets. Breaking force in femur and bone volume in tibial proximal metaphysis were significantly lower in the acidotic groups than those in the control groups in LCD, LmCD and SCD. In the acidotic groups, osteoid thickness was significantly higher in LCD than that in LmCD, HmCD and HCD. Mineral apposition rate in the acidotic groups was significantly higher in LCD and LmCD than that in HmCD and HCD. These results suggest that bone mineral loss and bone fragility under metabolic acidosis may be accelerated by high turnover of bone metabolism due to insufficient dietary Ca intake, but can be prevented by adequate supplementation of Ca.

Acidosis↗
PubMed1996

Spontaneous disappearance of a cerebral arteriovenous malformation.

A 63-year-old male presented with a cerebral arteriovenous malformation in the dominant motor area which subsequently disappeared spontaneously. He had suffered from epileptic attacks in his right extremities for 2 years before he first presented aged 53 years. He was treated with anticonvulsants and was followed up. Bleeding from the cerebral arteriovenous malformation occurred when he was 61 years old. Two years later, angiography revealed the complete disappearance of the cerebral arteriovenous malformation. Such spontaneous disappearance is rare, and the patient should be followed up as the nidus may reappear later.

Adolescent↗
PubMed1996

[Otoacoustic emissions of full-term and preterm neonates].

Transiently evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), and spontaneous otoacoustic emission (SOAE) were measured in 45 full-term neonates (68 ears) and 12 preterm neonates (20 ears) with ILO88 & 92. Measurements were performed in the nursery of the obstetrics ward or NICU (not sound proof room) under natural sleeping condition after nursing. No sedating agent was used. TEOAEs were rated "good response" in 61 (89.7%) of 68 full-term neonate ears. DPOAEs were rated "good response" in 40 (71.4%) of 56 full-term neonate ears. SOAEs were detectable in 25 (62.5%) of 40 full-term neonate ears. Considering the high positive rate of TEOAE in full-term neonates and the easy and noninvasive method of measurement, we concluded that TEOAE is useful for auditory screening in neonates. There was failure to detect TEOAEs in 7 ears and the measurements were all performed within 6 days after birth. Some reports claim that residual amnion in the external auditory canal or the middle ear in the first few days after birth causes slight hearing loss. Thus, we expected that making the measurements more than 7 days after birth might yield higher "good response" rates. We sometimes found that the Total Echo Powers of TEOAEs were reduced by the poor condition of the ear probe. Thus, we must be very careful in regard to this technical problem in order to perform accurate examinations. Because of its lower "good response" rate, DPOAE was not as useful for screening as TEOAE. Because of the movements or respiratory noises of the newborn infants, it was hard to detect reliable DPOAEs, particularly in the low frequency range. On the other hand, because of its frequency specificity, particurally at high frequencies, DPOAE will be useful for detecting the partial hearing impairment such as congenital high-tone hearing impairment. It would be difficult to use SOAE as a clinical test. Because it is not an evoked response, its mechanism of generation is not well understood. We expect that following longitudinal changes in SOAE in neonates may yield some information about it. We measured mainly TEOAE in preterm neonates because we had to complete the measurements as soon as possible. High Total Echo Powers of TEOAEs were recorded in most infants over 38 weeks of PCA (post conceptional age). The earliest case showed reliable TEOAE at 35 weeks PCA. In most cases that could be measured twice on different days, the Total Echo Powers of TEOAE, were higher in the second time. We therefore concluded that TEOAE might serve as an examination for monitoring the maturation of preterm neonate hearing.

Female↗