Endoscopic photodynamic therapy using talaporfin sodium for recurrent intranasal carcinomas after radiotherapy in three dogs.

Radiation is the treatment of choice for canine nasal tumours but, in almost all cases, there is local recurrence associated with poor prognosis. This report describes the effect of endoscopic photodynamic therapy using talaporfin sodium for canine intranasal carcinoma recurring after radiation therapy. Rhinoscopic photodynamic therapy was administered after radiation therapy in three dogs with recurrent intranasal carcinoma. Two to 24 illuminations of a 665-nm diode laser were performed two hours after intravenous bolus injection of 5·0 mg/kg of talaporfin sodium. Photodynamic therapy induced almost complete remission and prolonged survival time in all cases suggesting that it might be a useful treatment for intranasal carcinomas that recur after radiation.

Novel biomedical imaging approach for detection of sentinel nodes in an experimental model of gastric cancer.

BACKGROUND: The aim of this study was to validate a novel imaging system that uses ATX-S10Na(II) to detect sentinel nodes (SNs) in gastric cancer. The new technique was compared with the enhanced visualization method using indocyanine green (ICG). METHODS: Human gastric carcinoma cells were implanted orthotopically into 50 nude rats, which were divided into two groups. In the first group (n = 25), ATX-S10Na(II) was injected subserosally into the implanted site and visualized by a fluorescence spectrolaparoscope. In the second group (n = 25), ICG was similarly injected and observed through a near-infrared laparoscope. The presence of metastatic tumour cells was determined by reverse transcriptase-polymerase chain reaction specific for human beta-actin. RESULTS: ATX-S10Na(II) was clearly identified as a bright red colour, and was rapidly incorporated into the lymphatic system. Detection rates of SNs were 100 (95 per cent confidence interval (c.i.) 52 to 100) per cent (25 of 25) for ATX-S10Na(II) and 95 (95 per cent c.i. 40 to 100) per cent (21 of 22) for ICG. Sensitivity was 96 (95 per cent c.i. 45 to 100) and 81 (95 per cent c.i. 58 to 95) per cent respectively. CONCLUSION: These results support the validity of the ATX-S10Na(II)-guided approach in the detection of SNs in gastric cancer in vivo.

The wound-healing effect of fibrin glue for tracheal anastomosis in experimental pulmonary surgery.

The leakage of tracheal anastomoses is one of the major complications that occurs after tracheal reconstruction. Improved reinforcing methods for anastomoses would thus be clinically useful. To find a better technique, we examined the postoperative would-healing effect of fibrin glue on tracheal anastomosis in the rat. Experimental rats were divided into two groups. In the control group (n = 21), the trachea was anastomosed by interrupted absorbable sutures. In the fibrin glue group (n = 21), the trachea was anastomosed in the same manner as the control group, with the addition of fibrin glue around the area of anastomosis. In the two groups, we studied the amount of hydroxyproline and histological findings on the seventh, 14th, and 21st postoperative day. The amount of hydroxyproline and collagen fibers in the fibrin glue group was more than in the control group on the seventh postoperative day. These results suggest that fibrin glue has a promotive effect in the healing of tracheal anastomosis.

Active-oxygen involvement in canine NK-mediated cytotoxicity.

We examined the relationship between natural killer (NK) cell-mediated cytotoxicity, the produced active-oxygen and cytotoxic factor (CF) release in co-culturing canine NK cells with tumor cells (CL-1 target cells). In co-culturing, the adding of n-propyl gallate (active-oxide scavenger) removed the produced active-oxygen, which inhibited NK cell-mediated cytotoxicity and the CF release. Moreover, adding of this agent inhibited the tyrosine phosphorylation of NK intracellular protein which observed in co-culturing. Therefore, the active-oxygen produced from canine NK cells are thought to relate the signal transduction in NK-mediated cytotoxicity.

Influence of ageing on blastogenesis of mouse thymocytes in response to concanavalin A.

The influence of ageing on the blastogenic response of mouse thymocytes to a mitogen was investigated. Thymocytes from mice of various ages (10-70 days) were incubated with the mitogen, concanavalin A, to induce blastogenesis. The thymocytes were then incubated with [3H]thymidine, and the radioactivity of [3H]thymidine taken up by the cells was measured. The stimulation index (ratio of radioactivity uptake by cells incubated with and without mitogen) was used as a measure of blastogenesis of thymocytes. The stimulation index of thymocytes from 10-day-old mice was 2.9; it increased with age, reaching a peak of 33.7 in 40-day-old mice and then gradually decreasing to 8.2 in 70-day-old mice. The blastogenesis of thymocytes, an indicator of thymus function, was thus found to change considerably with age.

Morphological observation of canine natural killer cells mediated cytotoxicity.

The cytotoxic effects of canine NK cells on CL-1 target cells were examined by scanning electron microscopy (SEM). NK cell mediated cytotoxicity on CL-1 target cells was detected by 51Cr release assay. SEM showed that a canine NK cell extended projections to the CL-1 target cell. Furthermore, the surface of CL-1 target cells changed a mesh-like structure. Therefore, the cytotoxic effects of canine NK cells on CL-1 target cells were morphologically demonstrated.

Inhibitory effects of indomethacin on implantation and its related phenomena.

The dose-response relationship for the inhibitory effect of indomethacin on implantation and continuance of pregnancy was examined in four groups of rabbits administered with indomethacin (2.5, 5.0, 7.5 and 10.0 mg/kg) during the implantation period and compared with a control group. Implanted fetuses and corpora lutea were counted by laparotomy, and the number of offspring born was noted. The inhibitory effect of indomethacin on implantation was found to be dose-dependent, and the birth rate decreased in the indomethacin groups compared with the control group. As a result, even where implantation had been achieved, death of the implanted fetuses occurred at a high rate in rabbits administered with indomethacin during the implantation period.

Blockade of ovulation in rabbits by RU-486, a competitive progesterone antagonist.

The effect of an anti-progesterone compound, RU-486, administration (20-150 mg) on ovulation in rabbits was investigated. All of the seven control oil-treated rabbits ovulated, whereas, ovulation was blocked in one (12.5%) of eight rabbits treated with 20 mg RU-486, and in 4-6 (66.7-85.7%) of the 6 or 7 rabbits treated with 40-150 mg RU-486. Two successive injections of 10 mg progesterone (P) 4 and 8 hr after RU-486 injection did however recover ovulation in 3 (75.0%) out of 4 rabbits. These results indicate that P secreted from mature follicles during the ovulatory LH surge also play a significant role in follicular rupture of the rabbit, a copulatory ovulator.

Effects of TNF-alpha injection into the ovarian parenchyma on luteal blood vessels in rabbits.

It has been reported that tumor necrosis factor-alpha (TNF-alpha) derived from luteal macrophage is concerned with luteolysis. In the present study, to evaluate the correlation between TNF-alpha and regression of luteal blood vessels, recombinant human TNF-alpha (rh-TNF) was injected into the parenchyma of pseudopregnant rabbit ovaries. These injections were performed on day 7 of pseudopregnancy (functional luteal phase). Only Mg++ and Ca++ free phosphate buffer saline (PBS-) as the solvent was injected in the control group. Estimations of conditions in the luteal vessels after the injections was performed by observations of luteal vascular corrosion casts under a scanning electron microscope. Concentrations of serum progesterone before or after the injection were also assayed. In the control group, no change in the structure of luteal vessels was observed after PBS-injection, but regressing blood vessels with strictures, obstructions and rugged surfaces on the vessels were observed, and also concentrations of serum progesterone decreased noticeably after rh-TNF injection. These findings suggest that TNF-alpha plays a role in angiolysis through luteolysis in the rabbit corpus luteum.

Effects of splenectomy on luteolysis in pseudopregnant rabbits.

The effects of splenectomy on luteolysis in pseudopregnant rabbits were observed. Pseudopregnancy was induced in the rabbits by mating with vasoligated mature males and injection of human chorionic gonadotrophin (D0). In these rabbits, the concentration of serum progesterone increased for 7 days after the induction of pseudopregnancy. In the control group (sham-operation), the concentration of serum progesterone returned to the level of the pre-ovulatory levels by 14 days of pseudopregnancy. On the other hand, in the splenectomized group, in which splenectomy was performed at D7, the serum progesterone concentration was maintained at the level of the functional luteal phase (D7) at least until 21 days of pseudopregnancy. These findings indicate that the spleen is concerned with luteolysis of the rabbit.

Superovulation induction by human menopausal gonadotrophin in rabbits.

Superovulation induction in laboratory animals is an important technique as a means of providing eggs for embryonic research. Superovulation induction by human menopausal gonadotrophin (HMG) has not been fully established in rabbits. In the present study, the relationship between the dosage of injected HMG and the superovulatory response including fertilization rate was studied. The most satisfactory result was obtained in the group in which 30 iu of HMG was injected subcutaneously three times at 24-hr intervals. The superovulatory response by this method was considerably better than that by conventional six injections of follicle-stimulating hormone (FSH) having been widely accepted.

Pregnancy by tubal insemination in rabbits using sperm cells capacitated in vitro.

It has been suggested that the mechanical interference involved in inserting a tube into the oviduct before ovulation, during tubal insemination, may impair the capacity of the tubal fimbriae to pick up ovulated eggs. When fresh sperm cells are used, the semen has to be injected into the oviduct before ovulation to allow time for sperm capacitation. In the present study in rabbits, sperm cells capacitated by pre-incubation in vitro were injected into the oviducts through the tubal fimbriae after ovulation. Two of the six rabbits inseminated became pregnant and gave birth to one and three offspring, respectively. Injecting capacitated sperm cells after ovulation may avoid the potential problems posed by mechanical damage of the tubal fimbriae.

Simplification of superovulation induction by using polyvinylpyrrolidone as a solvent for FSH in rabbits.

With a view to simplify the method of inducing superovulation in rabbits, polyvinylpyrrolidone (PVP) was used as a solvent for follicle-stimulating hormone (FSH). As a result, it became clear that more than the equivalent number of ovulation points and fertilized ova that are obtainable by the conventional six injections of FSH were able to be obtained by only a single injection of FSH-PVP preparation. Inflammation or swelling of the tissue was not observed in the injection site or its vicinity. The results seem to enable simplification of superovulation induction by using PVP as a vehicle for FSH in rabbits. This finding could reduce injection distress to the animals and labor of the operator.

Effects of an oil contrast medium on fertilization in the oviduct in rabbits.

The influence of an oil contrast medium on fertilization in rabbit oviducts was investigated. The oil contrast medium (Lipiodol-UF) was injected into the catheterized oviducts of anaesthetized animals, and they were mated 1, 3, 5 or 7 days later. When mating took place 1 day after injection, none of the ova that were subsequently recovered were fertilized; the fertilization rates when mating occurred 3, 5 or 7 days after injection of the medium were 78.9, 90 and 100%. Fertilization within the oviduct was, thus, impaired by the injection of oil contrast medium, but appeared to be fully recovered 7 days later.

Effects of anti-progesterone compound RU486 on ovulation in immature mice treated with PMSG/hCG.

The effects of RU486, a competitive antagonist of progesterone, on ovulation were studied in PMSG/hCG-treated immature mice. PMSG/hCG was administered to 3-week-old female mice to induce ovulation. A dose of 0.5 mg of RU486 was administered 3 h before hCG injection, simultaneously with hCG injection, or 3, 4.5, 6, 7.5 or 9 h after hCG administration. The lowest number of ovulated eggs was observed in the group given RU486 6 h after hCG injection. Although the mean number of ovulated eggs was only 4.4 in this group, it was increased to 25.7 by supplementary administration of 2.0 mg of progesterone. It was demonstrated that RU486 had inhibitory effects on ovulation, and the inhibition could be prevented by supplementary administration of progesterone.

Implantation in both of the uterine horns after the unilateral intrauterine insemination in rabbits.

Artificial insemination was carried out by injecting semen into the upper part of the left uterine horn in rabbits with a duplex uterus. Ovulation was then induced by administration of hCG. As a result, implanted fetuses were observed not only in the left uterine horn but also in the right uterine horn. However, when similar insemination was carried out after ligation of the right utero-tubal junction, fertilization did not occur in the right oviduct. From these finding, we conclude that some of the spermatozoa injected into the left uterine horn was discharged into the vagina, entered the right uterine cervical canal, and reached the right oviduct to fertilize the ova.

Pregnancy by means of tubal insemination and subsequent spontaneous pregnancy in rabbits.

The purpose of the study was to determine whether or not physical stimulation by tubal insemination had any unfavourable influences upon the tubal fimbria. Tubal insemination was carried out on 14 rabbits and subsequent pregnancy results were monitored. After a period of 69-123 days following tubal insemination, 10 of the rabbits were mated spontaneously and these rabbits were then monitored for pregnancy. Newborn were obtained, with normal gestation periods in six out of the 14 rabbits, following tubal insemination and all 10 of the rabbits that were mated spontaneously with males following tubal insemination subsequently delivered. It is concluded that physical stimulation by tubal insemination does not produce adhesive changes on the tubal fimbria.

Geometric aberration of a generalized Wolter type I telescope. 2: Analytical study.

Geometrical aberration of a modified Wolter type I telescope is studied analytically.

Geometrical aberration of a generalized Wolter type I telescope.

Using two hyperboloids, we can control spherical aberration and coma of an imaging x-ray telescope. The coma-free condition is satisfied only at a particular radius of the first mirror. The best performance is obtained when we allow the coma-free condition at the outer edge and cancel about half of the defocused image for the largest height of an object by introducing spherical aberration.