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Biomedical subjects

S S Han

Publications and source records attributed to S S Han.

At least 91 records · Page 5Linked to original sources
PubMed1993

Teratogenicity study of Scutellariae Radix in rats.

This teratogenicity study was carried out in pregnant S.P.F. Sprague-Dawley female rats. These animals received for a period of 11 days, from day 7 to 17 of gestation, by daily oral administration, the water extract concentrates of the medicinal herb, Scutellariae Radix, at dose levels of 0.25 g/kg (group I), 12.49 g/kg (group II), and 24.98 g/kg (group III). Two-thirds of pregnant females in each group were sacrificed on day 20 of gestation and their fetuses were examined. The remaining dams were allowed to litter naturally, and postnatal development of the offspring was observed. There was a significant (P < 0.05) dose-dependent increase in the incidence of skeletal variations (presence of lumbar rib). There was also a dose-dependent increase in the incidence of abnormal urinary system (mainly dilatation of ureter) although the abnormality incidence of group III was comparable to group II. There were no significant differences between the control and treated groups in maternal body weight, intake of diet and water, efficiency of diet, hematologic values, resorbed and dead fetuses, corpora lutea, separation of eyelids, emergence of abdominal hair and incisors, traction test values, sex organ function in fetuses, and growth of fetuses.

Abnormalities, Drug-Induced↗
PubMed1993

Teratogenicity study (segment II) of recombinant granulocyte-macrophage colony stimulating factors (LBD-005) in rats.

A teratogenicity study was carried out in Sprague-Dawley rats subcutaneously injected recombinant Granulocyte-Macrophage Colony Stimulating Factors (LBD-005), the growth of stem cell and the development of the hematopoietic cell, at dose levels of 250, 500 and 1000 micrograms/kg/day for a period of 11 days from day 7 to day 17 of gestation. Two-thirds of the pregnant females in each group were sacrificed on day 20 of gestation and their fetuses were examined. The remaining dams were allowed to litter naturally, and the postnatal development of the offspring was observed. The incidences of external, internal and skeletal anomalies were not significantly increased in the fetuses of any treated groups. Recombinant GM-CSF caused no effects on parturition, lactation, postnatal growth and reproductive ability of the male and female offsprings.

Abnormalities, Drug-Induced↗
PubMed1993

Peri- and postnatal study (segment III) of recombinant granulocyte-macrophage colony stimulating factors (LBD-005) in rats.

A perinatal and postnatal study was carried out in Sprague-Dawley rats subcutaneously injected recombinant Granulocyte-Macrophage Colony Stimulating Factors (LBD-005), the growth of stem cell and the development of the hematopoietic cell, at dose levels of 250, 500 and 1000 micrograms/kg/day for a period from day 17 of gestation to day 21 after delivery. All pregnant dams were allowed to litter naturally, and the postnatal development of the offsprings was observed. The incidences of external, internal and skeletal anomalies were not significantly increased in the F1 and F2 fetuses of any treated groups. Recombinant GM-CSF caused no effects on parturition, lactation, postnatal growth and differentiation, behaviour and reproductive ability of the male and female offsprings.

Animals↗
PubMed1993

An acute toxicity study of recombinant human interferon alpha A (LBD-007) in Sprague-Dawley rats.

The acute toxicity of a recombinant human interferon alpha A (code name: LBD-007) was evaluated in both sexes of Sprague-Dawley rats, 5 weeks old, by the oral, subcutaneous and intravenous routes of administration. Based on the results, LBD-007 was not considered to induce any toxicological effect on the rats in mortalities, clinical findings, body weights and gross findings. It is suggested that LD50 values in rats would be > 48 x 10(8) IU/kg in the study of oral administration and > 24 x 10(8) IU/kg in the study of subcutaneous or intravenous administration.

Administration, Oral↗
PubMed1993

A 4-week subcutaneous toxicity study of recombinant human interferon alpha A (LBD-007) in Sprague-Dawley rats.

Recombinant human interferon alpha A (code name: LBD-007) was subcutaneously administered to both sexes of Sprague-Dawley rats at the doses of 0, 6, 12 and 24 x 10(6) IU/kg of body weight five days per week for 4 weeks to evaluate the subchronic toxicity. 20 to 50% of rats except the male control group showed minimal to mild, focal to multifocal renal mineralization. Whether renal mineralization is related to the test substance is not elucidated. Male rats dosed at 24 x 10(6) IU/kg showed the decrease of the absolute kidney weights and the increase of the brain relative weights. Female rats dosed at 24 x 10(6) IU/kg showed the increase of the absolute and relative ovary weights, and the decreases of specific gravity, bilirubin and urobilinogen in urine. However, no drug-related changes were noted in clinical findings, body weights, food consumption, water consumption, hematology, blood clinical chemistry and necropsy findings. Based on the results it is concluded that the estimated subcutaneous non-toxic dose of the recombinant human interferon alpha A (LBD-007) in rats is (6 approximately 12) x 10(6) IU/kg.

Animals↗
PubMed1993

A 6-month subcutaneous toxicity study of recombinant human interferon alpha A (LBD-007) in Sprague-Dawley rats.

Recombinant human interferon alpha A (code name: LBD-007) was subcutaneously administered to both sexes of Sprague-Dawley rats at the doses of 0, 3, 6 and 12 x 10(6) IU/kg of body weight six days per week for 6 months to evaluate the chronic toxicity. Male rats dosed at 12 x 10(6) IU/kg for 26 weeks showed a decrease of ketone body in the urine, and female rats dosed at 12 x 10(6) IU/kg for 26 weeks showed a decrease of serum alkaline phosphatase. Microscopic changes with remarkable incidence were nephropathy, renal mineralization and ultimobranchial cysts of the thyroid gland in all groups of both sexes of rats. These changes were not considered to be drug-related toxicity because they appeared to be minimal, occasionally mild in severity and did not have dose-dependency as well as clinical significance. In general, no drug-related change was noted in clinical findings, body weights, food consumption, water consumption, hematology, organ weights and necropsy findings. Based on the results, it is concluded that the estimated subcutaneous non-toxic dose of the recombinant human interferon alpha A (LBD-007) in rats would be 6 x 10(6) IU/kg.

Alkaline Phosphatase↗
PubMed1993

A study on antigenicity of recombinant human interferon alpha A (LBD-007) in mice and guinea pigs.

Antigenicity of recombinant human interferon alpha A (LBD-007), a newly developed drug for myeloid leukemia and hepatitis, was investigated in mice and guinea pigs. The following results were obtained: 1. Mice showed no production of antibodies against LBD-007 inoculated with aluminum hydroxide gel (alum) as an adjuvant, judged by the heterologous anaphylaxis (PCA) test using rats. On the other hand, antibodies against ovalbumin (OVA) inoculated with alum were definitely detected. 2. In the studies with guinea pigs, both the inoculation of LBD-007 only and of LBD-007 with complete Freund's adjuvant (CFA) as an adjuvant did not produce positive reactions in any of homologous active systemic anaphylaxis (ASA). On the other hand, the inoculation of ovalbumin with complete Freund's adjuvant (CFA) produced positive reaction in both of PCA and ASA. 3. These findings suggested that LBD-007 has no antigenic potential in mice or guinea pigs.

Anaphylaxis↗
PubMed1992

High-performance liquid chromatographic determination of rifapentine in serum using column switching.

A high-performance liquid chromatographic method with column switching has been developed for the determination of rifapentine in serum. The serum samples were injected onto a precolumn packed with Corasil RP C18 (37-50 microns) after simple dilution with an internal standard in a 1% ascorbic acid solution. Polar serum components were washed out using 0.05 M phosphate buffer. After valve switching, the concentrated drugs were eluted in the back-flush mode and separated by a mu Bondapak C18 column with acetonitrile-tetrahydrofuran-0.05 M phosphate buffer (pH 7.0) (42:5:53, v/v/v) as the mobile phase. The method showed excellent precision with good sensitivity and speed, and a detection limit of 0.1 microgram/ml. The total analysis time was less than 25 min and the mean coefficients of variation for intra- and inter-assay were less than 4.8%. The method has been successfully applied to serum samples from dogs after the oral administration of rifapentine.

Animals↗
PubMed1989

Composition of the rumen ciliate population in experimental herds of cattle and sheep in Lethbridge, Alberta, Western Canada.

Rumen ciliate populations were surveyed in 11 Holstein cattle and 6 sheep in Lethbridge (Alta., Canada) to determine species distribution in this Western Canadian environment. A total of 28 ciliate species were identified in cattle and 17 in sheep. The average total number of ciliates per millilitre of rumen content was 6.9 X 10(4) in cattle and 1.9 X 10(5) in sheep. The average number of species per host was 20.5 in cattle and 13.8 in sheep. Of the ciliate species detected, species of Entodinium appeared most frequently both in cattle and in sheep. Diplodinium polygonale, Eodinium lobatum, Eo. monolobum, Eremoplastron rostratum, Ostracodinium clipeolum, Os. mammosum, and Ophryoscolex purkynjei were not detected in sheep. In contrast, Ophryoscolex caudatus was not found in cattle. These data indicate that the ciliate faunas of cattle and sheep in this Western Canadian environment are similar to those found in Japan.

Alberta↗
PubMed1988

Arthropod immune system. V. Activated immunocytes (granulocytes) of the German cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae) show increased number of microtubules and nuclear pores during immune reaction to foreign tissue.

The German cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae) has two major immunocytes (blood cells) (granulocytes (GRs) and plasmatocytes). The GRs participate both in encapsulation and phagocytosis of nonself tissue. Structurally, the GRs are flattened and discoid, and contain, among other organelles, microtubules that are arranged in the form of a bundle in their peripheral region in the plane of flattening. If one implants a foreign tissue in the cockroach's abdomen, the GRs become activated and begin to encapsulate the implant by flattening and wrapping around it. The activated GRs show considerable increase in the number of both the microtubules and the nuclear pores of the nuclear envelope. Such structural changes in an activated arthropod immunocyte and their functional significance in its immune reaction against a foreign tissue have not been previously reported. We believe that the large number of microtubules is necessary not only to maintain the flattened nature of the GRs, but also to ensure the formation of an effective capsule against the deforming and shearing forces of the foreign tissue. And to keep up with the rapid assembly of new microtubules during encapsulation, the nucleus apparently triggers the synthesis of tubulin via ribosomes, its nuclear pores serving as channels for molecular transport to and from the nucleus. A structural and functional analogy between GRs and human platelet has also been suggested.

Animals↗
PubMed1986

Extracranial vascular angiography.

Noninvasive procedures (ultrasound, CT, and MRI) are increasingly valuable in the diagnosis of diseases of the head and neck. Angiography, however, is still essential in the demonstration of vascular pathology, including the preoperative evaluation of vascular neoplasms. Through angioplasty and embolization techniques, angiography also plays a leading role in the treatment of arteriosclerotic vascular disease, vascular malformations, and vascular neoplasms.

Angiography↗
PubMed1984

A study of computer-assisted tomography. II. Comparison of metrizamide myelography and computed tomography in the diagnosis of herniated lumbar disc and spinal stenosis.

One hundred twenty-two patients with surgically confirmed pathology consisting of either herniated lumbar disc, spinal stenosis, or both were included in this investigation. For each of these patients, preoperative metrizamide myelography and computerized tomography were performed. Each myelogram and CT scan was read blindly so that the neuroradiologist interpreting the study had no knowledge of the patient's surgical pathology, clinical examination, nor any knowledge of the interpretation of the other preoperative test. A painstaking attempt was made to describe precisely both the exact nature of the preoperative myelogram and CT scan interpretations. The correlations between the preoperative interpretation of each test and the observed surgical findings then were analyzed statistically. Based upon this analysis, myelography was found to be more accurate than computed tomography in the diagnosis of herniated lumbar disc (83% vs. 72%). In the diagnosis of spinal stenosis, myelography was slightly more accurate than computed tomography (93% vs. 89%). Based upon the results of this study, the authors conclude that metrizamide myelography is more accurate than computed tomography in the diagnosis of both herniated lumbar disc and spinal stenosis and remains the diagnostic study of choice for these conditions. Furthermore, metrizamide myelography gives the added advantage of visualizing the thoracolumbar junction and, thus, affords the opportunity to diagnose occult spinal tumors.

False Negative Reactions↗
PubMed1983

Effect of parasympathetic denervation on acetylcholine levels in the rat parotid gland. Is there an extraneuronal pool of acetylcholine?

Parasympathetic denervation of the rat parotid gland by avulsion of the auriculotemporal nerve caused a marked and lasting decrease in gland weight. Parasympathectomy did not change the levels of choline in the gland but decreased by 60% the levels of acetylcholine (ACh) ten days after surgery and 65% at 28 days. It is puzzling that relatively high levels of ACh remained after parasympathetic denervation. The presence of additional cholinergic nerves that innervate the gland, or pass through it en route to other structures may account for some of the remaining ACh. Also, Schwann cells from denervated nerves might have contributed to some of the ACh. The existence of an extraneuronal source of ACh is considered.

Acetylcholine↗
PubMed1983

Absorption of 4,4'-methylenebis [2-chloroaniline] by human skin.

A system was developed to measure percutaneous absorption of water-insoluble environmental agents into human skin. Percutaneous absorption of 4,4'-[14C]methylenebis [2-chloroaniline] (MBOCA) was measured during dry contact exposure of MBOCA with organ cultures of neonatal foreskin. Time-dependent exposures, autoradiographs, and thin-layer chromatography indicated that MBOCA was rapidly and progressively absorbed and passed through the skin without being metabolized. The transepithelial penetration of MBOCA was temperature dependent. Under certain conditions, the stratum corneum contained more MBOCA than other layers in the skin, which suggested that the stratum corneum may not be the main barrier for percutaneous absorption of MBOCA. An assessment of risk confirmed that skin exposure is a cause for concern.

Autoradiography↗
PubMed1983

Effects of socialization games on proximity and prosocial behavior of aggressive mentally retarded institutionalized women.

Socialization games, designed to reinforce prosocial behavior between moderately and severely mentally retarded aggressive institutionalized women, were presented to two groups on 12 occasions over 8 weeks, randomly interspersed with 12 sessions of arts and crafts or filmstrip stories. Half of the sessions were presented in the morning and half in the afternoon. Video-taped observations of interpersonal behavior for 10 minutes after each session were analyzed in terms of friendly, unfriendly, and inactive behavior, and the distance of each subject from each other subject was measured. The rate of friendly behavior was significantly greater after the games and was higher in morning than afternoon sessions. The games also significantly decreased interpersonal distance. Both unfriendly behavior and inactivity were higher after the "placebo" sessions. The relevance of these results to institutional programming was discussed.

Adult↗
PubMed1982

Changes in the synthesis of exportable and nonexportable proteins in parotid glands during aging.

The age-related differences in the synthesis of exportable and nonexportable proteins of the parotid salivary gland were compared in 2- and 24-months-old rats. Parotid slices from these rats were incubated in the presence of [14C]leucine and the amount of radioactivity incorporated into the water-soluble proteins of the postmicrosomal supernatant was compared. The exportable and nonexportable proteins were identified by electrophoretic separation of these proteins by comparing the banding patterns of the gel preparations from unstimulated glands to those from the glands stimulated to secrete. The radioactivity determination in various protein bands from these rats indicated that the synthesis of exportable secretory proteins declined with age, while that of nonexportable proteins did not appear to change.

Aging↗