Biomedical subjects

K Seo

Publications and source records attributed to K Seo.

At least 19 recordsLinked to original sources

PubMed1992

Effect of calcium antagonists on postischemic protein biosynthesis in gerbil brain.

BACKGROUND AND PURPOSE: Prolonged inhibition of protein synthesis precedes delayed neuronal death in the CA1 sector of the hippocampus after transient cerebral ischemia. Organic calcium antagonists have been recommended for alleviation of ischemic neuronal damage. The present study was undertaken to investigate whether these drugs improve the recovery of protein biosynthesis after interruption of cerebral blood flow. METHODS: Cerebral protein synthesis was measured biochemically and autoradiographically in gerbils submitted to 5 minutes of bilateral occlusion of the common carotid arteries followed by 2 hours or 2 days of recirculation. Flunarizine (25 mg/kg) or nimodipine (1.5 mg/kg) were applied intraperitoneally shortly after ischemia. RESULTS: Treatment with either calcium antagonist did not markedly influence postischemic recovery of protein synthesis in the resistant regions of the brain and did not prevent the persisting inhibition in the vulnerable stratum pyramidale of the CA1 sector of the hippocampus. CONCLUSIONS: The postischemic application of the organic calcium antagonists nimodipine and flunarizine does not promote postischemic recovery of protein synthesis. The beneficial effects of these drugs must, therefore, be based on other mechanisms.

Amino Acids↗

PubMed1992

[Inhibition of acute rejection of heart graft in rats without immunosuppressants after intrathymic myocardial cell inoculation in the neonatal period].

There have been no successful cases reported of organ transplantation in application of neonatal immunological tolerance. Isolated myocardial cells from Lewis (LEW/Crj) rat hearts were inoculated into the thymus of incompatible King (WKAH/Hkm) rats. Ten weeks later the heart from LEW donor was transplanted heterotopically to the WKAH rat that had inoculated intrathymic myocardial cells without immunosuppression (n = 4, Group 1). Group 2 was made up of 4 isografts of heart transplantation (nontreated isograft). Group 3 was made up 4 allografts of heart transplantation (nontreated allograft). The animals were killed 7 days after transplantation, and early rejection was evaluated by accumulation of iodine-125 (125I)-labeled antimyosin antibody (AMA) uptake and confirmed by histological examination. In Group 1 & 2, the value of I-125 AMA uptake ratio was small (Group 1; RV: 1.28 +/- 0.28, IVS: 1.29 +/- 0.28, LV: 1.43 +/- 0.25, Group 2: RV: 1.14 +/- 0.07, IVS: 0.95 +/- 0.06, LV: 1.16 +/- 0.21). This level of the value indicates that the rejection does not occur. On the other hand, in Group 3, the value was high (RV: 4.63 +/- 1.92, IVS: 4.42 +/- 1.75, LV: 4.45 +/- 1.73) compared with Group 1 & 2. This level indicate that the rejection is severe. In the histological studies, Group 3 showed necrosis of myocardial cells, while Group 1 with neonatal immunological tolerance showed only very mild lymphocytic infiltration. The histology of thymic tissue in Group 1, the LEW myocardial cells are surviving in the WKAH rat thymus.

Animals↗

PubMed1992

[DNA ploidy pattern of flow cytometry as indicator of degrees of malignancy and prognosis in colorectal cancers].

Cellular DNA content of primary colorectal cancers was measured by flow cytometry and investigated on clinico-pathological features to elucidate the relationship between DNA ploidy patterns and outcomes. IN 144 colorectal carcinomas, DNA diploid carcinomas accounted for 23% and DNA aneuploid carcinomas for 77%. NO significant difference was observed between DNA ploidy pattern and tumor differentiation, lymph node metastasis or lympangial invasion. DNA aneuploid tumor had a tendency to invade vein and to lead to hematogenic metastasis. Patients with DNA aneuploid tumor showed a significantly poor disease-free and overall survival rate. Significantly increased incidence of hematogenic recurrence was demonstrated in the DNA aneuploid cases. These results suggest that the DNA ploidy pattern of colorectal cancers may prove to be of prognostic value.

Adult↗

PubMed1992

[Pharmacokinetic and clinical studies on panipenem/betamipron in the pediatric field].

UNLABELLED: Panipenem/betamipron (PAPM/BP), one of the carbapenems, was studied for its absorption and excretion, and clinical efficacy. The following is a summary of the results: 1. Absorption and excretion: Fourteen patients with their ages between 2 years and 14 years were administered with PAPM/BP 10 mg/kg, 20 mg/kg or 30 mg/kg, in 30-minute intravenous drip infusion. Maximum serum levels of PAPM, at dose levels of 10 mg/10 mg/kg, 20 mg/20 mg/kg and 30 mg/30 mg/kg of PAPM/BP, were 27.37 micrograms/ml, 59.3 micrograms/ml, 91.7 micrograms/ml, respectively, at the end of infusion. The half-lives of the 3 dose levels were all within 0.90-0.96 hour. Mean peak serum levels of BP, at dose levels of 10 mg/10 mg/kg, 20 mg/20 mg/kg and 30 mg/30 mg/kg, were 21.77 micrograms/ml, 35.29 micrograms/ml, 50.08 micrograms/ml, respectively, with half-lives of 0.55-0.63 hour. Urinary recovery rates of PAPM in the first 8 hours after administration at dose levels of 10 mg/10 mg/kg, 20 mg/20 mg/kg and 30 mg/30 mg/kg, were 15.9-31.1%, 15.3-36.9%, 11.0-40.5%, respectively, and those of BP during the same time were 33.1-79.1%, 41.3-93.4%, 12.9-94.4%, respectively. 2. CLINICAL RESULTS: Thirty-nine patients, including 2 with purulent meningitis, 1 with septicemia (suspect), 18 with acute pneumonia, 5 with bronchiolitis, 2 with tonsillitis (unable to receive oral antibiotics), 3 with cervical purulent lymphadenitis, 2 with bacterial enteritis, 6 with urinary tract infections were treated with PAPM/BP at dose levels of 30-100 mg/kg/day. Clinical responses in the patients were excellent or good. Even 2 patients with purulent meningitis were treated with PAPM/BP at dose levels of no less than 20 mg/kg x 3 and 33 mg/kg x 3. Most of respiratory and urinary tract infection cases of moderate severities were treated at dose levels of 30-60 mg/kg/day, i.e., 10 mg/kg x 3 or 20 mg/kg x 3. No adverse reaction was observed. One patient suffered from frequent watery diarrhea but the drug was continued to be administered and the patient recovered quickly. Abnormal laboratory findings were noted, in 2 cases with elevation of platelet, in 1 case with elevation of GOT, in 1 case with elevation of monocyte, in 1 with eosinophilia, in 1 with eosinophilia and decrease in platelet count, in 1 with eosinophilia and elevation of GOT and in 2 with elevation of GOT and GPT, but these abnormalities in the 9 cases were slight and transient.

Adolescent↗

PubMed1992

[Pharmacokinetic and clinical studies on meropenem].

Pharmacokinetic and clinical studies on meropenem (MEPM, SM-7338), a new developed carbapenem, were performed and the following results were obtained. 1. Absorption/excretion: Pharmacokinetics of MEPM was studied in 9 children using doses of 10 mg/kg and 20 mg/kg by a 30 minute-drip infusion. Peak plasma levels and plasma half-lives of the 2 doses were 28.4 and 43.0 micrograms/ml, and 0.70 and 0.80 hours, respectively. Their urinary recovery rates were 42.5 to 67.6% and 29.9 to 62.6%, respectively. Cerebrospinal fluid levels and penetration rates of MEPM in a patient with purulent meningitis were 0.66 to 4.01 micrograms/ml and 1.6 to 12.2%, respectively. 2. Clinical study: Forty-nine patients were treated with MEPM at doses exceeding 100 mg/kg/day with purulent meningitis and 30 to 60 mg/kg/day with other infections. MEPM gave "excellent" or "good" responses in 48 cases, an efficacy rate of 98.0%. Only one patient with subdural abscess showed fair response. Diarrhea and rash were observed in 1 case each. Abnormal laboratory test results were noted in 5 patients including elevation of GOT, GPT and eosinophils. In no cases the treatment had to be discontinued.

Absorption↗

PubMed1992

Preterm birth is associated with increased risk of maternal and neonatal infection.

Much information suggests that maternal reproductive tract infections, both recognized and unrecognized, account for an important and possibly preventable portion of preterm births. If such infections do mediate instances of preterm labor and premature rupture of the membranes (PROM), then associated risks of subsequent maternal and neonatal infections would be increased, even after controlling for confounding variables. To evaluate possible associations between preterm birth and maternal and neonatal infections, we conducted a retrospective study of 9642 births at the University of Colorado Health Sciences Center between July 1980 and June 1985. Clinical chorioamnionitis occurred more frequently among women delivering before term with intact membranes at the onset of labor (5.8% preterm versus 1.7% term) and among women with PROM (26.5% preterm versus 6.7% term). Among the women delivered by cesarean, the incidence of postpartum endometritis was higher in those with preterm PROM than in those with term rupture of membranes. The incidence of neonatal infection increased significantly as the gestational age of the neonates decreased (P less than .01). The rate of culture-proven neonatal infection was significantly higher following PROM (P less than .01) than after birth without PROM. Both neonatal infection and perinatal mortality were increased in association with chorioamnionitis in both preterm and term pregnancies. These consistent observations complement and support suggestions that reproductive tract infection plays a possibly preventable role in the pathogenesis of preterm birth.

Adolescent↗

PubMed1991

Two-stage resuscitation of the cat brain after prolonged cardiac arrest.

Following prolonged cardiac arrest, reperfusion of the brain is endangered by the low blood perfusion pressure during the early resuscitation phase. In order to avoid low perfusion brain injury, a two-stage resuscitation protocol was applied to cats submitted to 30 min potassium chloride induced cardiac arrest: first, the heart was resuscitated, followed--after stabilisation of blood pressure--by recirculation of the brain. During cardiac resuscitation the brain was disconnected from the general circulation by inflating a pneumatic cuff around the neck. The results were compared with the outcome of conventional one-stage resuscitation following 15 min cardiac arrest. Cardiac resuscitation was successful in 5 out of 8 animals with 15 min and in 6 out of 13 animals with 30 min cardiac arrest. In successfully resuscitated animals of both groups, brain energy metabolism recovered to normal within 3 h although two-stage resuscitation increased brain ischemia time to 37-61 min. Two-stage resuscitation, in consequence, is a promising approach for revival of the brain after prolonged cardiac arrest.

Adenosine Triphosphate↗

PubMed1991

Antimicrobial therapy in preterm premature rupture of membranes: results of a prospective, double-blind, placebo-controlled trial of erythromycin.

This study was conducted to evaluate the effectiveness of oral erythromycin treatment in safely prolonging pregnancy among women experiencing preterm premature rupture of membranes. Sixty-five women were randomly assigned to receive double-blind treatment with either erythromycin base or an identical-appearing placebo three times daily for 7 days. Only women between 23 and 34 completed weeks' gestation who did not have an indication for delivery were enrolled in the study. Pretreatment microbiologic tests were obtained and women were followed expectantly. Fifty-five women and their newborns completed the protocol and were fully evaluated. Overall, time from rupture of membranes to onset of labor and to delivery was longer, although not significantly, for erythromycin-treated women. Similarly, there was a trend for reduced neonatal intensive care (level II, p = 0.07). When gestational age at enrollment was controlled, erythromycin treatment of women between 28 to 32 weeks' gestation was associated with a prolonged interval from enrollment to delivery [erythromycin: 292 hours (5 to 679); placebo: 54 (12 to 323); p less than 0.044]. Fifty percent of erythromycin-treated women between 28 to 32 weeks' gestation continued their pregnancies at least 13 days after premature rupture of membranes, whereas 50% of placebo-treated women were delivered of infants within 4 days (p = 0.02). Erythromycin treatment among women less than 28 and between 33 to 34 weeks' gestation was not associated with prolonged latency or other changes. There were no differences between erythromycin- and placebo-treated women in the occurrence of clinically recognized chorioamnionitis, postpartum endometritis, or neonatal infectious morbidity. In this double-blind, placebo-controlled trial, erythromycin treatment was well tolerated, safe, and associated with prolongation of pregnancy and reduced intensive neonatal care requirements for selected mother-newborn pairs with preterm premature rupture of membranes.

Adolescent↗

PubMed1991

Adjunctive clindamycin therapy for preterm labor: results of a double-blind, placebo-controlled trial.

A double-blind, placebo-controlled, randomized trial was conducted to evaluate the efficacy, safety, and tolerance of a course of clindamycin (administered for 3 days intravenously and 4 days orally) among hospitalized women with preterm labor at less than or equal to 34 weeks' gestation who were treated with tocolytics. One hundred three woman-perinate pairs were analyzed. Univariate analysis demonstrated that pregnancies were continued longer in women treated with clindamycin than in women who received placebo (clindamycin-treated group, 35 days; placebo-treated group, 25 days; p = 0.02). Survival analysis showed that pregnancy continued at least 35.5 days in 50% of clindamycin-treated women versus 20 days for control women (p = 0.03). Obstetric and microbiologic parameters associated with treatment outcomes were also sought. Women with bacterial vaginosis more often delivered preterm (p = 0.03; relative risk, 1.4; 95% confidence interval, 1.04 to 2.0). Among women with bacterial vaginosis, trends for increased duration of pregnancy (clindamycin-treated group, 36 days; placebo-treated group, 19 days), increased birth weight (clindamycin-treated group, 2634 gm; placebo-treated group, 2256 gm), and increased mean gestational age at delivery (clindamycin-treated group, 35 weeks; placebo-treated group, 34 weeks) were associated with clindamycin treatment. Women with either group B streptococcus, Chlamydia trachomatis, Trichomonas vaginalis, or Staphylococcus aureus were more likely to have preterm premature rupture of membranes (p = 0.01). Clindamycin treatment of these women reduced the incidence of preterm premature rupture of membranes to that of uninfected subjects. Stratification by gestational age at enrollment showed clindamycin treatment to be associated with an increased interval to delivery only among mothers enrolled before 33 weeks' gestation (clindamycin-treated group, 40 days; placebo-treated group, 28 days; p less than 0.05). Treatment with clindamycin appeared safe and well tolerated, with benefits limited to women who were less than or equal to 32 weeks' gestation.

Chemotherapy, Adjuvant↗

PubMed1991

Ischemic thresholds of cerebral protein synthesis and energy state following middle cerebral artery occlusion in rat.

The ischemic threshold of protein synthesis and energy state was determined 1, 6, and 12 h after middle cerebral artery (MCA) occlusion in rats. Local blood flow and amino acid incorporation were measured by double tracer autoradiography, and local ATP content by substrate-induced bioluminescence. The various images were evaluated at the striatal level in cerebral cortex by scanning with a microdensitometer with 75 microns resolution. Each 75 x 75 microns digitized image pixel was then converted into the appropriate units of either protein synthesis, ATP content, or blood flow. The ischemic threshold was defined as the flow rate at which 50% of pixels exhibited complete metabolic suppression. One hour after MCA occlusion, the threshold of protein synthesis was 55.3 +/- 12.0 ml 100 g-1 min-1 and that of energy failure was 18.5 +/- 9.8 ml 100 g-1 min-1. After 6 and 12 h of MCA occlusion, the threshold of protein synthesis did not change (52.0 +/- 9.6 and 56.0 +/- 6.5 ml 100 g-1 min-1, respectively) but the threshold of energy failure increased significantly at 12 h following MCA occlusion to 31.9 +/- 9.7 ml 100 g-1 min-1 (p less than 0.05 compared to 1 h ATP threshold value; all values are mean +/- SD). In focal cerebral ischemia, therefore, the threshold of energy failure gradually approached that of protein synthesis. Our results suggest that with increasing duration of ischemia, survival of brain tissue is determined by the high threshold of persisting inhibition of protein synthesis and not by the much lower one of acute energy failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗

PubMed1991

Summer-type hypersensitivity pneumonitis in a child.

Summer-type hypersensitivity pneumonitis (HP) is a unique disease in Japan. The clinical features of this disease are as follows: 1) cough, fever and dyspnea as a clinical triad, 2) diffuse reticulonodular opacities on the chest X-ray film, 3) restrictive impairment and decrease in DLco, 4) hypoxia, 5) initiation in summer, 6) worsening of the condition when the patient returns home, 7) granuloma formation and alveolitis in the lung biopsy specimen, 8) familial clustering. The etiologic agent of this disease is debatable. In 1984 Ando et al reported that the etiologic agent was T. cutaneum. Now many people are pursuing the argument to its logical conclusion. We report a case of summer-type HP. It is uncommon in children, especially in a child in whose serum antibody to T. cutaneum can be demonstrated.

Adolescent↗

PubMed1991

[Ureteral function at the ureterovesical junction. Action potentials of the canine intramural ureter during bladder filling or bladder contraction].

The relationship between bladder movements and the intramural ureter was studied in the dog by recording electromyograms of the intramural and extravesical ureters recorded during bladder filling and contraction. Bladder filling was achieved by instilling physiological saline at a rate of 10 ml/min to a volume of 5 ml/kg, while bladder contraction was induced by electrical stimulation. For electromyography, an electrode was inserted transperitoneal into both the extravesical ureter and the intramural ureter after it had been separated from the extravesical ureter. A cystostomy for the instillation of water and another cystostomy for the measurement of intravesical pressure were also made in the bladder. During bladder filling at an intravesical pressure of about 10 cmH2O, the frequency of the action potentials in the intramural ureter showed no significant difference to those in the extravesical ureter. In addition, during bladder contraction at a greatly increased intravesical pressure of about 5 times the precontraction level, the frequency of the action potentials in the intramural ureter was not significant by different from those in the extravesical ureter, and also from its own precontraction value. The above findings suggest that action potentials in the intramural ureter are not affected by bladder movements such as filling or contraction, and that the ureter continues to actively transport urine to the bladder during such movements.

Action Potentials↗

PubMed1991

Interleukin 4-mediated induction of CD4+/CD8+ T cells during infancy.

Neonatal human CD4+ T cells will co-express CD8 on their surface following short-term culture with interleukin 4 (IL-4). Adult T cells do not respond in this manner. In this study we examine this phenomenon as a function of age and determine that IL-4 responsiveness decreases with time to approach adult levels at about 2 years. This phenomenon may be relevant to the documented ability of neonatal CD4+ T cells to function as suppressors.

Adolescent↗

PubMed1991

[Pharmacokinetic and clinical evaluation of cefpirome in the pediatric field].

We conducted a pharmacokinetic and clinical study on cefpirome (HR 810, CPR), an aminothiazolylmethoxyiminoacetamido cephalosporin (ATOIC), and obtained the following results. 1. Concentrations in blood/excretion in urine. We studied pharmacokinetic in children upon intravenous bolus injections and 30-minute and 1-hour intravenous drip infusions in single dosages of 10, 20, and 40 mg/kg, and obtained virtually the same results as those found in adult subjects. Upon intravenous bolus injections, mean blood concentrations 30 minutes after administration of 10, 20, and 40 mg/kg were 26.1, 47.8, and 82.8 micrograms/ml, respectively, and half-lives were 1.13, 1.43, and 1.26 hours, respectively. Upon 30-minute intravenous drip infusion, mean blood concentrations on completion of the drip infusions of 10, 20, and 40 mg/kg were 43.2, 106.9, and 163.0 micrograms/ml, respectively, and half-lives were 1.15, 1.09, and 1.15 hours, respectively. In addition, upon 1-hour intravenous drip infusion, mean blood concentrations on completion of infusion were 27.1 micrograms/ml for 10 mg/kg and 47.5 micrograms/ml for 20 mg/kg, and half-lives were 1.09 and 1.40 hours, respectively. A clear dose response was observed at all dosages for either administration method. Mean excretion rates in urine in the first 8 hours after administration were 60.6-71.1% upon intravenous bolus injections of 10-40 mg/kg, and upon intravenous drip infusion, the values were 50.2-83.8% for administration of 10-40 mg/kg 6 or 7 hours after completion of drip infusion. 2. Concentrations in the cerebrospinal fluid Penetration into the cerebrospinal fluid was studied in 2 subjects, and a concentration of 0.28-5.19 micrograms/ml was observed upon administration of 50 mg/kg, a moderate degree of penetration compared to the penetration of cephalosporins of group 5 studied up to now. 3. Clinical results Evaluation of clinical effects of CPR on various types of bacterial infections was conducted in 56 subjects, excluding 3 subjects who had diseases which were excluded from the study. The breakdown was as follows: 3 cases of meningitis, 1 case of septicemia, 25 cases of bronchial pneumonia, 1 case each of tonsillitis and infection of the external acoustic meatus, 2 cases each of scarlet fever and phlegmon, 8 cases each of lymphadenitis and urinary tract infections, and 5 cases of staphylococcal scalded skin syndrome. Results of excellent or good were obtained in 54 subjects for an efficacy rate of 96.4%.(ABSTRACT TRUNCATED AT 400 WORDS)

Absorption↗

PubMed1990

Cervicovaginal microflora and pregnancy outcome: results of a double-blind, placebo-controlled trial of erythromycin treatment.

Available information suggests that some instances of preterm birth or premature rupture of membranes are associated with clinically unrecognized infection and inflammation of the lower uterine segment, decidua, and fetal membranes. Various cervicovaginal microorganisms have been recovered from these sites. Many of these microorganisms produce factors that may lead to weakening of the fetal membranes, release of prostaglandins, or both. This study evaluated the presence of various lower genital tract microflora and bacterial conditions in 229 women enrolled in a double-blind, placebo-controlled trial of short-course erythromycin treatment at 26 to 30 weeks' gestation to prevent preterm birth. Demographic, obstetric, and microbiologic parameters were prospectively evaluated. Premature rupture of membranes occurred less frequently (p less than 0.01) among women who received erythromycin (6%) versus placebo (16%). Preterm premature rupture of membranes also occurred less frequently, although not significantly (p = 0.3) in patients who received erythromycin (2%) versus placebo (5%). Erythromycin treatment significantly decreased the occurrence of premature rupture of membranes among women who were initially positive for Chlamydia trachomatis infection. Logistic regression analysis demonstrated that C. trachomatis (p = 0.05; odds ratio, 9), vaginal wash phospholipase C (p = 0.08; odds ratio, 6) and prior preterm birth (p = 0.007; odds ratio 17) were associated with increased risk of preterm birth. Bacterial vaginosis, Mycoplasma hominis, Ureaplasma urealyticum were not significantly associated with increased risk of preterm birth or preterm rupture of membranes. These findings support a role for selected lower genital tract microflora in preterm birth and premature rupture. Large controlled treatment trials of specific infections or conditions associated with preterm birth and premature rupture of membranes are required to confirm the value of antimicrobial treatments in prevention of microbial-associated preterm birth.

Adolescent↗

PubMed1990

Cross-reactive polysaccharide antigens (types a, d, and h) of the mutans group of streptococci: different molecular forms of the type as distinguishable by monoclonal antibodies.

As compared to the previous precipitin inhibition tests differences were found in the reactivities of monoclonal antibodies (MAbs), a-4 and a-84 with Streptococcus cricetus (serotype a) in an enzyme immunoassay using whole cells, purified cell wall antigen and haptenic sugars coated onto microtitre wells. Investigation into the differences led to the finding that the purified antigen from S. cricetus cells consisted mainly of three forms with different molecular weights and sugar contents. MAb a-4 reacted with a high molecular weight form (AgI, molecular weight of 46,000) and low molecular weight forms (AgII and AgIII, molecular weights of 9,800 and 20,000, respectively) whereas MAb a-84 reacted only with the high-molecular form. Gas chromatographic analysis revealed that all antigens contained rhamnose, galactose and glucose but in different ratios of the sugars. Although the binding site of AgII/AgIII with MAb a-4 seemed to be slightly different from that of AgI with MAb a-84, the predominant immunodeterminant of the antigens was considered to be the same. On the basis of these results, the chemical structures of the antigenic determinants are suggested. The nature of the antigen-antibody reactions is discussed.

Antibodies, Monoclonal↗

PubMed1990

A side reaction in solid phase synthesis. Insertion of glycine residues into peptide chains via Nim----N alpha transfer.

In solid-phase peptide synthesis using N alpha-Boc-Nim-tosyl-histidine (Boc-His(Tos)), byproducts having extra Gly residues in the peptide chain were observed at a high rate. When a Boc-amino acid such as Asn was incorporated after assembly of Boc-His(Tos), the Nim-tosyl group was partially or fully cleaved by an activating agent, 1-hydroxybenzotriazole. In the successive coupling reactions, Boc-Gly was incorporated into the free Nim ring as well as the alpha-amino function, and the Nim-Gly was then transferred to the alpha-amino group of Gly of the peptide chain after removal of these Boc groups to give extra Gly residues at the position of Gly. This was observed in only the coupling reaction with Boc-Gly and could be circumvented using a more stable Nim protecting group for His, such as a dinitrophenyl group.

Amino Acid Sequence↗

PubMed1990

Ureteral action potential and histological changes in the upper urinary tract receiving the formalin.

The present study investigates the ureteral action potential and histological changes of pelvi-ureteral system after injection of the formalin into the obstracted ureters or the renal pelvis. In the first experiment, formalin was injected into the obstructed ureters of 18 dogs for 30 minutes. In the second, formalin was injected into the obstracted renal pelvis of 13 dogs for 30 minutes using ureteral balloon catheters, and then renal pelvis were released from obstraction and catheters were removed. In these experiments, ureteral electromyogram were recorded and histological changes of pelvi-ureteral system were also observed microscopically. Results 1. After injection of formalin into the ureters, ureteral action potential disappeared and had not restored. Histologically, damage was observed in the ureteral smooth muscle as well as in the mucosa. 2. After injection of formalin into the renal pelvis, ureteral action potential disappeared in 46% of the ureters. In 54% of the ureters, action potential had not disappeared, however discharge interval became irregular. Histological changes of the renal pelvis was not related to the presence or absence of ureteral action potential. The results of the present study show that ureteral smooth muscle play part in the conduction of the ureteral excitation, and have an irregular autonomic discharge.

Action Potentials↗