DNA double-strand break rejoining deficiency in TK6 and other human B-lymphoblast cell lines

TK6, WI-L2, SB and three other B-lymphoblast lines were deficient in the rejoining of DNA double-strand breaks (DSBs) induced by ionizing radiation. Cells of these cell lines rejoin less than 50% of the breaks in 60 min after exposure, as assayed by filter elution at pH 9.6. The deficiency in TK6 cells was confirmed using the comet assay. IN TK6 cells the percentage of DSB rejoining did not vary markedly with dose and was similar for G1, S, and G2 + M-phase cells. Two B-lymphocyte lines (Raji and GM0606), three T-lymphoblast lines (MOLT-4, Jurkat, and CCRF-HSB-2), HL-60 promyelocytes, and GM3440 human skin fibroblasts rejoined more than 50% of the DSBs in this period after exposure. Radiation sensitivity in terms of cell survival was measured in those cells forming colonies. Of the cell lines tested, those that were deficient in DSB rejoining were radiation-sensitive (TK6 and WI-L2: D0 = 0.64 Gy). However, not all lines that were proficient in DSB rejoining were radiation-resistant, since Jurkat and GM0606 cells were relatively radiation-sensitive (D0 = 0.63-0.73 Gy). TK6 and WI-L2 cells were more sensitive to bleomycin (D0 = 8-9 micrograms/ml) than were HL-60 and Raji cells (D0 = 40-54 micrograms/ml). No relationship of DSB rejoining to V(D)J recombinase activity was observed, since no mRNA hybridizing to the cDNA probes for RAG-1 or RAG-2 was detected in any of the cell lines tested.

Self-pumped phase conjugation of 18 degrees -cut Ce-doped KNSBN crystal at 632.8 nm

We report the self-pumped phase conjugation of an 18 degrees -cut Ce-doped (K(y)Na(1-y))(2m)(Sr(x)Ba(1-x))(1-m) Nb(2)O(6) crystal at a 632.8-nm He-Ne laser wavelength. A maximum phase-conjugation reflectivity of 84.3% has been measured. In addition, its incident angular response and time response are measured.

Pharmacological study of 14 beta-(thioglycolamido)-7,8-dihydro-N(cyclopropylmethyl)-normor phinone (N-CPM-TAMO)

Opioid effects of 14 beta-(thioglycolamido)-7,8-dihydro-N(cyclopropylmethyl)- normorphinone (N-CPM-TAMO) were studied in the mouse tail-flick and acetic acid writhing assays. In the tail-flick test, N-CPM-TAMO failed to produce any antinociception after i.c.v. administration of up to 300 nmol. However, pretreatment of mice with N-CPM-TAMO produced a time- and dose-dependent antagonism of morphine-induced antinociception. The antagonism by N-CPM-TAMO lasted up to 48 hr, with a maximal effect at 24 hr after i.c.v. administration. Similarly, pretreatment of mice with N-CPM-TAMO at 24 hr also produced a dose-dependent antagonism of kappa-mediated antinociception, induced by U50,488 However, the antagonistic potency of N-CPM-TAMO against U50,488 was 100-fold less than against morphine. Pretreatment with N-CPM-TAMO had no effect on delta opioid receptor-mediated antinociception, as measured with [D-Pen2,D-Pen5]enkephalin. In the writhing assay, N-CPM-TAMO produced a time- and dose-dependent antinociception after i.c.v. administration, with a value of the dose producing 50% analgesia of 18.4 (10.6-31.9) nmol. The antinociceptive effect lasted up to 3 hr after administration. N-CPM-TAMO-induced antinociception was antagonized by coadministration of the kappa-selective antagonist, norbinaltorphimine. Pretreatment of mice with N-CPM-TAMO also produced a time- and dose-dependent antagonism of U50,488-induced antinociception, which lasted up to 72 hr, with a maximal effect at 24 hr after administration. These data indicate that N-CPM-TAMO is a mu-selective, long-term antagonist.(ABSTRACT TRUNCATED AT 250 WORDS)

5 beta-Methyl-14 beta-(p-nitrocinnamoylamino)-7,8-dihydromorphinone: a long-lasting mu-opioid receptor antagonist devoid of agonist properties

5 beta-Methyl-14 beta-(p-nitrocinnamoylamino)-7,8-dihydromorphinone (MET-CAMO) suppressed morphine-induced antinociception but had no effect on antinociception mediated by delta- or kappa-opioid receptors after a single i.c.v. 1-nmol injection from 8 to 72 h before testing. MET-CAMO had no agonist effects in the mouse tail-flick assay in doses up to 100 nmol. MET-CAMO is the first N-methylated morphine derivative which shows such long-lasting mu-selective opioid receptor antagonism with no agonistic properties.

Hypothalamic-pituitary function assessment in children by a combined stimulation test

We utilized a combined stimulation test using insulin, thyrotropin-releasing hormone, gonadotropin-releasing hormone and levodopa to assess multiple pituitary hormones including growth hormone, thyrotropin, prolactin and gonadotropins in 32 children of short stature and 18 girls with early appearance of puberty. It was found that this combined stimulation test can assess multiple hormone responses with satisfactory results in a single 90-min test. Compared with any of those laborious classic stimulation tests alone, it is easier to be carried out and willingly accepted by children.

Enhanced self-pumped phase conjugation from 16 degrees -cut KNSBN:Cu

With the maximum coupling coefficient and high internal reflection conditions, the self-pumped phase-conjugation reflectivity of copper-doped potassium sodium strontium barium niobate (KNSBN:Cu) is increased with 16 degrees -cut samples. The response time is also shortened. The resolution property of 16 degrees -cut KNSBN:Cu is determined and a distorted image is corrected by using the 16 degrees -cut sample.

Antinociceptive properties of two alkylating derivatives of morphinone: 14 beta-(thioglycolamido)-7,8-dihydromorphinone (TAMO) and 14 beta-(bromoacetamido)-7,8-dihydromorphinone (H2BAMO)

This study investigated the antinociceptive properties of two alkylating derivatives of morphinone, 14 beta-(thioglycolamido)-7,8- dihydromorphinone (TAMO) and 14 beta-(bromoacetamido)-7,8-dihydromorphinone (H2BAMO) in the mouse tail-flick assay. Intracerebroventricular administration of either TAMO or H2BAMO produced short-term antinociception. Both TAMO and H2BAMO were 11.6-fold more potent than an i.c.v. administration of morphine. These effects were antagonized by the mu-selective antagonist, beta-funaltrexamine, but not by the delta-selective antagonist, N,N-diallyl-Tyr-Aib-Aib-Phe-Leu-OH. TAMO pretreatment from 8 to 48 hr produced a time-related, dose-dependent antagonism of morphine-induced antinociception without showing any agonistic effect. Pretreatment with TAMO for 24 hr antagonized antinociception produced by both H2BAMO and morphine, as well as TAMO itself, but not that of the delta-selective agonist [D-Pen2,D-Pen5]enkephalin (DPDPE) or U50,488, a kappa-selective agonist. In order to distinguish this antagonistic effect from cross-tolerance between TAMO and morphine, two mu agonists, [D-Ala2,N(Me)Phe4,Gly-ol]enkephalin (DAMGO) and H2BAMO, were chosen for comparison. A single i.c.v. pretreatment of DAMGO or H2BAMO, at a dose that had equivalent analgesic effects as TAMO, attenuated morphine-induced antinociception, reaching a maximal effect at the time of the disappearance of agonistic effects of DAMGO and H2BAMO and lasting up to 24 hr. Additionally, a 16-hr pretreatment with TAMO, but not DAMGO or H2BAMO, reduced the development of physical dependence to morphine at 24 hr after morphine pellet implantation. Therefore, this study demonstrated that both TAMO and H2BAMO act as mu opioid agonists to produce short-term antinociception.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuronal damage, glial response and cerebral metabolism after hypothermic forebrain ischemia in the rat

We investigated the effect of 30 degrees C whole body hypothermia on neuronal injury, astroglial reactivity and intracellular pH in rats subjected to 15 min of forebrain ischemia. Experimental groups included: (1) normothermic ischemia (n = 8), ischemia induced under 37 degrees C body temperature, (2) hypothermic ischemia (n = 6), ischemia induced under 30 degrees C body temperature. Cerebral intracellular pH was measured using in vivo 31P NMR spectroscopy over 7 days. Neuronal injury and astrocytic reactivity were evaluated using hematoxylin and eosin staining, and immunoreactivity to glial fibrillary acidic protein, respectively. Normothermic animals revealed significant alkalosis (P less than 0.01) at 48 h after ischemia compared to the pre-ischemic value. No significant intracellular pH change was detected after ischemia in the hypothermic group. Ischemic neuronal injury was prevented in the hypothermic animals, compared to the severe neuronal injury found in the normothermic animals (P less than 0.01). The marked astrocytosis of normothermic animals was significantly inhibited in the hypothermic animals (P less than 0.01). Our data indicate, that hypothermia significantly inhibits neuronal injury as well as post-ischemic alkaloids and astrocytosis, induced by 15 min of forebrain ischemia in the rat.

In vivo 31P NMR study of combined hyperthermia and photodynamic therapies of mammary carcinoma in the mouse

Although the sequence and time interval effects of combined photodynamic therapy (PDT) and hyperthermia tumor treatments have been studied using survival curves, tumor regrowth, and cloning assays, the metabolic response to combined treatment measured by nuclear magnetic resonance (NMR) spectroscopy has not yet been clarified. In this study, mammary carcinoma in the flank of C3H mice was subjected to PDT (12.5 mg/kg Photofrin II, 632 +/- 1 nm at 200 J/cm2) and water bath hyperthermia (43.5 degrees C, 30 min) with no delay or 4 h delay between treatments. In vivo 31P-NMR spectroscopy was employed to measure energy metabolism and pH of the tumors before and serially after treatment for up to 1 week. The data revealed significant differences in the time course of high energy phosphate levels between treatment combinations, which may reflect the biological effectiveness of the combined treatments. Our observations indicate that 31P-NMR spectroscopy can be used to evaluate the metabolic response of tumors to treatment with combined PDT and hyperthermia.

1H magnetic resonance imaging of normal brain tissue response to photodynamic therapy

1H Magnetic resonance imaging (MRI) was used to study the effects of photodynamic therapy (PDT) on normal rat brain (n = 5) using T1-, T2-, diffusion-, and proton density (rho)-weighted images. Rats received intraperitoneal injections of 12.5 mg/kg of Photofrin II, and 48 hours later the dural area over the frontal cortex was treated with 35 J/cm2 of light (632 +/- 1 nm). The T1-, T2-, and diffusion-weighted images revealed an evolving high contrast region of brain that corresponded to the PDT-treated area. Lesioned brain exhibited significant increases in T1 and T2 relaxation times at 1 day (P less than 0.01) and 3 days (T1, P = 0.018; T2, P less than 0.01) after treatment, compared with the contralateral equivalent volume of nonlesioned brain. Water proton diffusion coefficient (DW) in the lesioned area decreased at 1 day (P = 0.026) and increased at 3 days (P = 0.012) compared with nonlesioned brain. An increase in the proton density ratio (rho D/rho O) from PDT (rho D) versus nonlesioned side (rho O) was found 3 days after PDT treatment (P = 0.03). The data indicate that the biophysical parameters obtained from magnetic resonance imaging scans, T1, T2, DW, and proton density, can be used to monitor changes in an evolving photochemically induced lesion.

Observation of the beat between two independent light sources by a method of time-delayed laser-induced double gratings

A novel method of time-delayed laser-induced double gratings has been proposed to study the beat between two independent light sources. Our experimental results indicate that we can obtain good interference patterns even when the coherence time of the laser source is only a few picoseconds. This new technique can be used to measure the frequency difference between two laser fields.

Dose-dependent thermal response of tumor pH and energy metabolism evaluated by in vivo 31P NMR spectroscopy and microelectrodes

In vivo 31P NMR spectroscopy and pH microelectrodes were employed to measure the energy metabolism and pH of a mammary carcinoma in the flank of the C3H mouse before and serially up to a week after various hyperthermia treatments. Water bath hyperthermia was used to treat the tumor at 43.5 degrees C for 30 min (TCD0/30, NMR measurement only), 1 h (TCD10/30), and 2 h (TCD60/30), respectively. The data indicate that, except at 4 h after TCD60/30 treatment, all pH values measured by NMR (pHn) were significantly higher (P less than or equal to 0.001) compared to pH values measured by microelectrodes (pHe) at all treatment levels and times. The magnitude of the difference between pHn and pHe (delta pH) was significantly decreased from the pretreatment level only at 4 h after hyperthermia treatment (0.51 pH units for TCD60/30 and 0.21 pH units for TCD10/30). The ratio of beta-nucleoside triphosphate to inorganic phosphate (beta-NTP/Pi) and pHn were more sensitive to hyperthermia treatment than pHe. The beta-NTP/Pi ratio failed to recover to the pretreatment ratio after 1 or 2 h hyperthermia treatment, while a total recovery was observed within 72 h for 30 min hyperthermia treatment. Our data suggest that the temporal profile of beta-NTP/Pi, pHn, and delta pH may be indicative of the biological outcome of hyperthermia treatment.

Differential antagonism of opioid delta antinociception by [D-Ala2,Leu5,Cys6]enkephalin and naltrindole 5'-isothiocyanate: evidence for delta receptor subtypes

The present study has investigated the direct opioid delta receptor-mediated antinociception produced by i.c.v. administration of the highly selective delta agonists, [D-Pen2,D-Pen5]enkephalin (DPDPE) and [D-Ala2]deltorphin II, as well as that of the less delta-selective [D-Ser2,Leu5,Thr6]enkephalin (DSLET), by using two novel nonequilibrium opioid antagonists, [D-Ala2,Leu5,Cys6] enkephalin (DALCE) and naltrindole 5'-isothiocyanate (5'-NTII). At times ranging from 8 to 48 hr after a single i.c.v. pretreatment of mice with 5'-NTII, the antinociceptive effects of [D-Ala2] deltorphin II were significantly antagonized. In contrast, 5'-NTII pretreatment at times between 10 min and 24 hr failed to antagonize the antinociceptive effects of DPDPE. Previous studies have shown that pretreatment with i.c.v. DALCE produces a dose- and time-related antagonism of DPDPE, but not morphine, antinociception. However, pretreatment with i.c.v. DALCE failed to antagonize the antinociceptive effects of [D-Ala2]deltorphin II. Similarly, i.c.v. administration of DSLET produced time- and dose-related antinociception which was partially antagonized by either beta-funaltrexamine (beta-FNA) or by ICI 174,864 (N,N-dialyl-Tyr-Aib-Aib-Phe-Leu-OH), suggesting mixed activity at mu and delta receptors. ICI 174,864 produced essentially complete antagonism of DSLET antinociception in beta-FNA-pretreated mice. Pretreatment with 5'-NTII (at -8 to -48 hr), blocked the antinociception produced by DSLET in control or in beta-FNA-pretreated mice. In contrast, pretreatment with DALCE failed to antagonize the antinociception produced by i.c.v. DSLET in either control or in beta-FNA-pretreated mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Interaction of beta-funaltrexamine with [3H]cycloFOXY binding in rat brain: further evidence that beta-FNA alkylates the opioid receptor complex

beta-Funaltrexamine (beta-FNA) is an alkylating derivative of naltrexone. In addition to acting as an irreversible inhibitor of mu-receptor-mediated physiological effects, intracerebroventricular (i.c.v.) administration of beta-FNA to rat attenuates the ability of selective delta receptor antagonists and naloxone to reverse delta receptor-mediated effects. Moreover, recent work demonstrated that i.c.v. administration of beta-FNA alters the conformation of the opioid receptor complex, as inferred by a decrease in the Bmax of the lower affinity [3H][D-ala2,D-leu5]enkephalin binding site. Consistent with the decreased potency of naloxone as an inhibitor of delta receptor mediated effects, beta-FNA doubled the naloxone IC50 for displacing [3H][D-ala2,D-leu5]enkephalin from its lower affinity binding site. These data collectively support the hypothesis that the opioid receptor complex postulated to mediate mu-delta interactions in vivo is identical to the opioid receptor complex as defined by vitro ligand binding studies. A direct prediction of this hypothesis is that beta-FNA should increase the Kd of antagonists for the mu binding site (mu cx) of the receptor complex. The data reported in this paper demonstrate that beta-FNA doubled the IC50 of the potent narcotic antagonist, 6-desoxy-6 beta-fluoronaltrexone (cycloFOXY) for displacing [3H][D-ala2,D-leu5]enkephalin from its lower affinity binding site, and doubled the Kd of [3H]cycloFOXY for its mu binding site, providing additional data that the mu binding site labeled by [3H]cycloFOXY is the mu binding site of the opioid receptor complex. beta-FNA also altered the kappa binding site labeled by [3H]cycloFOXY, and when administered intrathecally to mice, beta-FNA produced a longlasting antinociception in the acetic acid writhing test.

Bombesin differentially affects gastric emptying in suckling, weanling and adult rats

The gastric effect of bombesin, a homolog of the mammalian peptide found in breast milk, was studied in suckling, weanling and adult rats (11, 30 and 90 days old, respectively). Control gastric emptying was not different in the three age groups. When bombesin was given orogastrically in a saline vehicle, 30 min before a nonabsorbable radiolabeled marker (used to assess gastric emptying), a significant and dose-related inhibitory effect was observed in sucklings. In contrast to the data with orogastric peptide in saline, when bombesin was given orogastrically in rat milk 30 min before the marker, there was no effect on gastric emptying in sucklings. Inhibition of gastric emptying was again demonstrated in the sucklings when bombesin (0.6-30 micrograms) was given with an artificial rat milk substitute 30 min before the marker. In contrast, orogastric bombesin in rat milk or rat milk substitute had no effect on gastric emptying in weanlings or adults. While s.c. bombesin in saline did not alter gastric emptying in sucklings, s.c. administration of the peptide produced a significant and dose-related increase in gastric emptying in both weanlings and adults. These results support the concept that milk-borne peptides, such as gastrin releasing peptide, may be involved in regulation of gastric function in suckling rats.

[Studies on chromosome aberrations and dyshemopoiesis in myelodysplastic syndromes]

G banding chromosome analysis of bone marrow cells from 51 cases of MDS, including 34 cases of RA, 4 cases of RAS, and 13 cases of RAEB, was carried out using a short term culture method. The morphological abnormalities of dyspoiesis of 46 patients were studied and correlated with chromosomal changes. The results were as follows: Forty-nine percent of the cases had abnormal karyotypes. The frequency of clonal abnormalities was 36.8 percent in RA and RAS, and 84.6 percent in BAEB. The most important aberrations were +8 in 7, HSR in 2, and "spontaneous" PCC in 6 cases. The latter 2 abnormalities had rarely been reported in the literature. Other findings included 1p+, dup (1) (q25q44), -2, 4p+, -5, 5q-, +8p, -12, 12p+, 12q-, -14, 14q+, t (1; 14), -15, +/-16, +/-17, -18, +19, +20, 20q-, +/-21, +/-22, -X, -Y, +Mar, etc. The study also showed a close relation between chromosome aberrations and dyspoiesis. +8 patients tended to have a high percentage of micronuclei in their erythroblasts, and their dyspoiesis usually involved three cell lineages. Patients with PCC were found to have more polyploid metaphases (in cytogenetic studies) and more multinuclear cells (in bone marrow aspirate slides). The results of our study revealed that the more severe dyspoiesis is, the higher the frequency of chromosome aberrations. We consider chromosome abnormalities to play an important role in the pathogenesis of MDS, with cell fusion being involved as well.

Selective modulation of morphine antinociception, but not development of tolerance, by delta receptor agonists

Co-administration of delta opioid agonists at doses which do not produce measurable antinociception were demonstrated to produce an increase in the antinociceptive potency of morphine in the mouse tail-flick test. In contrast, co-administration of equi-antinociceptive combinations of a delta agonist plus morphine for three days resulted in the development of less tolerance to morphine antinociceptive actions. The data indicate that while acute antinociceptive effects of opioid mu agonists are modulated by delta agonists, the development of antinociceptive tolerance is not.

Molecular cloning and expression of the rat angiotensinogen gene

To identify tissue- and hormonal-specific DNA control cis-elements in the rat gene, we have constructed fusion genes consisting of various lengths of the 5'-flanking region of the rat angiotensinogen gene linked to a human growth hormone (hGH) reporter gene and have introduced them into a subclone of rat pancreatic islet tumor cell line (1056A) which expresses the highest level of angiotensinogen mRNA. As a negative control, we have also introduced them into a human choriocarcinoma cell line (JEG-3), which does not express the endogenous angiotensinogen gene. The level of the expression of these fusion genes in these cells was determined by the level of immunoreactive hGH secreted into the culture medium. The expression of angiotensinogen-growth hormone (ANG-GH) fusion genes, pOGH (ANG N-1498/+18), pOGH (ANG N-688/+18), pOGH (ANG N-110/+18), pOGH (ANG N-53/+18), and pOGH (ANG N-35/+18) was 1.0, 1.8, 1.5, 12.0 and 3.0-fold higher, respectively, than the promoterless growth hormone expression vector (pOGH). The addition of dexamethasone (10(-6) M), aldosterone (10(-5) M), and thyroid hormone, L-T3 (10(-7) M), stimulated the expression of pOGH (ANG N-1498/+18) by 4.0-, 2.5-, and 2.0-fold above the control level, respectively. Combination of dexamethasone (10(-6) M), L-T3 (10(-7) M), and ethinyl-estradiol (10(-6) M) stimulated the expression of the pOGH (ANG N-1498/+18) to greater than 10-fold over the control. Ethinyl-estradiol (10(-6) M) or progesterone (10(-6) M) alone had no effect on the expression of the pOGH (ANG N-1498/+18).(ABSTRACT TRUNCATED AT 250 WORDS)

Opioid modulation of basal intestinal fluid transport in the mouse: actions at central, but not intestinal, sites

Central and peripheral sites of opioid action on net basal fluid transport were studied in loops of jejunum in urethane-anesthetized mice. Intracerebroventricular administration of morphine, [D-Ala2, N-MePhe4, Gly-ol]enkephalin (DAMGO), D-Pen2, D-Pen5] enkephalin (DPDPE) or U50,488H produced dose-related increases in net basal intestinal absorption. Intracerebroventricular DAMGO was approximately 2.6, 1278 and 2674 times more potent than morphine, DPDPE and U50,488H, respectively. The increase in net basal fluid absorption mediated by i.c.v. administration of all these compounds, except DPDPE, was antagonized in a dose-related manner by coadministration of i.c.v. naloxone, an opioid antagonist which did not produce any effects when given alone. Neither the increase in net basal fluid absorption produced by DPDPE nor the fluid transport effects produced by the other agonists tested was antagonized by the delta antagonist, N,N-diallyl-Tyr-alpha-aminoisobutyric acid [( Aib]-Aib-Phe-Leu-OH) and no effects were observed with this delta antagonist alone. Intracerebroventricular administration of beta-funaltrexamine (18.8 nmol, 4 hr before testing) blocked the i.c.v. effects of DAMGO, but not those of U50,488H. In contrast to the effects seen following i.c.v. administration of these agonists, no changes in net basal fluid transport were obtained by the i.p. route for DAMGO, DPDPE, [D-Ala2,D-Leu5]enkephalin, [D-Ala2, Met5]enkephalinamide or U50,488H; of the compounds tested, only morphine produced an increase in net basal fluid absorption after i.p. administration. The effects of i.c.v. or i.p. morphine were blocked by i.c.v. SR 58002C, a quaternary opioid antagonist which had no effects alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Modulation of morphine antinociception by peripheral [Leu5]enkephalin: a synergistic interaction

This study determined whether the modulation of morphine antinociception by [Leu5]enkephalin, a compound which does not produce detectable antinociception when given i.p., was additive or synergistic. Co-administration of graded i.p. doses of morphine and [Leu5]enkephalin 20 min before testing resulted in a progressive leftward and parallel displacement of the i.p. morphine dose-response line. The increase in potency produced by i.p. [Leu5]enkephalin, but not the antinociception of i.p. morphine alone, was blocked by i.c.v. ICI 174,864. The data demonstrate strong and dose-related synergism between the two compounds, supporting the view that (a) peripheral administration of [Leu5]enkephalin can modulate morphine antinociception, apparently at the level of the brain and (b) that the interaction between mu and delta opioid agonists is not the result of simple additive action at the same (i.e., mu) receptor. Further evidence is thus provided for the existence of functional mu-delta interactions.

Dose-dependent metabolic response of mammary carcinoma to photodynamic therapy

The metabolic response of mammary carcinoma in the C3H mouse to photodynamic therapy (PDT) was measured using in vivo 31P nuclear magnetic resonance (31P-NMR) spectroscopy and pH microelectrodes. Twenty-four hours after administration of Photofrin II (12.5 mg/kg), the tumor was subjected to photoactivation using an argon dye laser. Optical treatment doses were 200, 400, and 600 J/cm2 and corresponded to the following tumor control doses: TCD10/30, TCD50/30, and TCD90/30, respectively. In vivo 31P-NMR spectra and pH micro-electrode measurements were obtained prior to treatment and at 4, 24, 48, and 72 h and 1 week post-treatment. The data revealed a significant (P less than 0.0002) alkalosis as indicated by the pH measured by NMR compared to pH measured by microelectrodes at all treatment levels and time points. Spectral differences between treatment groups were apparent as early as 4 h after treatment. The ratio of beta-nucleoside triphosphate to inorganic phosphate at 4 h after treatment was significantly (P less than 0.01) smaller for 600 J/cm2 treatment than for 200 J/cm2 treatment. At curative (600 J/cm2) levels, from 48 h on, no phosphate resonances were detected in the spectra. The pH measured by NMR transiently decreased from pretreatment levels after 200 and 400 J/cm2 treatment (P less than 0.002, P less than 0.009, respectively), while no change in pH from pretreatment values was found after 600 J/cm2 treatment. The data suggest that the early metabolic response of mammary carcinoma to PDT, as indicated by 31P-NMR spectroscopy, is dose dependent, and may be a sensitive indicator of biological outcome to treatment.

[Reaction between monoclonal antibodies to porcine zona pellucida and human and porcine ovary in vitro]

Reaction between monoclonal antibodies to porcine zona pellucida (LPD8, LPC4) and human and porcine ovaries was studied by ABC immunohistochemistry technique in vitro. When slices of human and porcine ovaries were stained with ABC, not only the zona pellucida but also the ovum cytoplasm was stained. Other regions of the ovary, such as granulosa cell, theca cell and connective tissue, could not be stained. These results suggest that the monoclonal antibodies to porcine zona pellucida probably have no direct effect on the endocrine function of ovary, but they may combine with ovum cytoplasm and inhibit follicular growth, so that the number of follicles reduces and endocrine function of the ovary decreases. We do not think that the prospects of continual study on LPD8, LPC4 are good.

Modulation of mu-mediated antinociception by delta agonists: characterization with antagonists

The functional interactions between supraspinal mu and delta receptors were characterized in the mouse using mu receptor-selective antagonists. The effects of pretreatment with the mu opioid antagonists, beta-funaltrexamine (beta-FNA) and naloxonazine on the modulation of morphine antinociception by the delta agonists [D-Pen2,D-Pen5]enkephalin (DPDPE) and [D-Ala2,Met5]enkephalinamide (DAMA) were studied. When co-administered in the same i.c.v. injection, a sub-antinociceptive dose of DPDPE consistently and significantly increased the antinociceptive potency of morphine in control animals, while a sub-effective dose of DAMA decreased morphine antinociception; both the respective increase and the decrease of morphine potency by DPDPE and DAMA had been previously shown to be blocked by ICI 174,864, a delta antagonist. Pretreatment of mice with the non-equilibrium mu antagonist beta-FNA 4 h prior to testing, a pretreatment which had no effect on i.c.v. DPDPE or DAMA antinociception, prevented the modulation of morphine antinociception by both DPDPE and DAMA. Pretreatment with the long acting mu 1 antagonist naloxonazine, 24 h prior to testing, failed to affect the modulation of morphine antinociception by either DPDPE or DAMA; such a pretreatment had no effect on the antinociceptive effects of DPDPE or DAMA when given alone. These results provide further support for the concept of a functionally coupled mu-delta receptor complex which is sensitive to antagonism by beta-FNA, but not naloxonazine, and support the notion that subtypes of opioid mu and delta (i.e. complexed and non-complexed) receptors may exist.

Sites of clonidine action to inhibit gut propulsion in mice: demonstration of a central component

The role of central (supraspinal and spinal) and peripheral alpha-adrenoceptors in the regulation of gastrointestinal propulsion in the mouse was studied using clonidine, an alpha 2-adrenoceptor agonist. Clonidine produced a dose-dependent inhibition of propulsion when given intracerebroventricularly, intrathecally, or subcutaneously, but was most potent when given intracerebroventricularly. The antitransit effects of centrally given clonidine were antagonized by intracerebroventricular (i.c.v.) yohimbine, but higher doses were required when this antagonist was given peripherally. Whereas i.c.v. and s.c. administration of clonidine were effective in inhibiting gut transit in spinally transected mice, intrathecal (i.th.) administration of this agonist was not. A supraspinal site of clonidine action is suggested based upon (a) the higher central to peripheral potency of clonidine; (b) the greater potency of i.c.v., compared with s.c., administration of yohimbine in blocking i.c.v. clonidine; (c) the lack of effect of i.th. administration of clonidine in spinally transected mice; and (d) the reduced potency of i.c.v., but not s.c., administration of clonidine in spinally transected mice. Additionally, a peripheral site of clonidine action is suggested by (a) the lower potency of i.c.v. yohimbine in blocking s.c., compared with i.c.v., clonidine; (b) the lower potency of i.c.v. yohimbine in blocking i.c.v. clonidine in transected mice (compared with normal mice); (c) the equal potency of s.c. clonidine in slowing propulsion in normal and spinally transected mice; and (d) the equal potency of i.c.v. yohimbine in blocking s.c. clonidine in normal and spinally transected mice. These data in mice would thus support the concept that normal (peripheral) therapeutic administration of clonidine would affect gut motor function by interactions within the brain and directly at the level of the gut.

A comparison of the central gastrointestinal antitransit effects of morphine and bombesin in the mouse

The gastrointestinal motor effects of centrally-given morphine and bombesin were compared in mice. Both compounds produced a dose-related decrease in the propulsion of a marker along the gut when given by the intracerebroventricular (i.c.v.) or intrathecal (i.th.) routes. Co-administration of the same compound by both routes was found to produce a marked increase in potency for morphine, but only a slight increase in potency for bombesin. Isobolographic analysis of the gut effects of these compounds revealed a multiplicative brain-spinal cord interaction for morphine, but an additive interaction for bombesin. These results are consistent with the interpretation that morphine can act at either the level of the brain or the spinal cord, activating independent pathways which ultimately converge to alter gut propulsion. In contrast, spinal bombesin requires communication to supraspinal sites in order for its gut effects to occur, suggesting activation of a common outflow pathway from the central nervous system.

Dual properties of cultured retinoblastoma cells: immunohistochemical characterization of neuronal and glial markers

The dual properties of two human retinoblastoma cell lines, WERI-Rb1 and Y79, were investigated with immunohistochemistry. Two neuron-specific markers, dopamine-B-hydroxylase (DBH) and tetanus toxin, and an astrocyte-specific marker, the glial fibrillary acid protein (GFAP), were applied for immunohistochemical reactions. With peroxidase-antiperoxidase (PAP) and immunofluorescence techniques, all of the WERI-Rb1 and Y79 cells showed consistently positive results with both neuronal and glial markers. The findings demonstrate that cultured retinoblastoma cells WERI-Rb1 and Y79 have both neuronal and glial properties.

Visual sustained attention: image degradation produces rapid sensitivity decrement over time

Perceptual sensitivity to a visual target presented in a random continuous sequence of targets and nontargets decreased rapidly over time when stimuli were highly degraded visually but not when moderately degraded or undegraded. Large declines in sensitivity, independent of changes in response criterion, were found after only 5 minutes of observation. These rapid decrements of sensitivity to degraded targets seem to result from demands on the limited capacity of visual attention.

Mapping and characterization of the hisD-unlinked nif mutants in Klebsiella pneumoniae

Two hisD-unlinked genes NifC5 and NifC7 are mapped in the chromosome of K. pneumoniae. The sequence of NifC5 and NifC7 is suggested as NifC5--gltB--NifC7--argG. The P1 infected E. coli lysate can transduce the mutant C-7 to be Nif+ transductant, yet fails to transduce the hisD-linked nif mutants to be Nif+ ones. This indicates that the gene encoding C-7 is not the structural gene of nitrogen fixation and is present in E. coli. It is actually a gene specifying the glutamate synthetase. SDS electrophoresis shows the marked low content of nitrogen reductase and immunoelectrophoretic test reveals the reduced amount of both nitrogenase and nitrogen reductase in the mutant cells.