Distinct neuronal populations specified to form corticocortical and corticothalamic projections from layer VI of developing cerebral cortex.

Layer VI of the cerebral cortex contains heterogeneous populations of pyramidal neurons whose axons project either cortically or subcortically. It has been shown that a subset of layer VI neurons expressing latexin projects ipsilaterally to other cortical areas but does not contribute to the corticothalamic projections. Taking advantage of the connectional specificity of latexin-expressing neurons, we here determine whether corticocortical and corticothalamic neurons are generated at different times, and at which stage the connectional distinction develops in corticogenesis. Our experimental findings indicate that: (1) thalamic-projecting neurons in layer VI of the rat secondary somatosensory cortex (SII) are born at embryonic day 14 or before while latexin-expressing neurons in the same layer are generated at embryonic day 15 or later; (2) axonal invasion by SII neurons into ipsilateral cortical areas and into the posterior dorsal thalamus mainly takes place early in the postnatal period; (3) latexin-expressing neurons never project toward the dorsal thalamus in normal development; (4) presumptive latexin-expressing neurons in the neonatal SII are able to grow into a cortical slice in vitro, but do not invade a thalamic slice even transiently; (5) thalamic-projecting neurons, on the other hand, fail to simultaneously establish connections with a cortical slice. Taken together, our findings suggest that the time frame in which presumptive corticocortical and corticothalamic neurons are generated differs, and that the two populations are restricted in connectional fate potential by the perinatal period prior to target innervation.

Correlation of pre-operative nutritional condition with post-operative complications in surgical treatment for oesophageal carcinoma.

AIMS: The relationship between the pre-operative nutritional condition and the outcome of the surgical treatment in patients with oesophageal carcinoma has been discussed diversely. The aim of the current study was to demonstrate the relationship between pre-operative nutritional condition and post-operative complications and prognosis following surgical treatment for oesophageal carcinoma. METHODS: Two hundred and fifty-eight patients with oesophageal carcinoma treated with oesophageal resection and reconstruction were selected. The correlation of pre-operative values of prognostic nutritional index (PNI) with the incidence of post-operative complications and prognosis of the patients was investigated. RESULTS: The mean pre-operative value of PNI in patients with post-operative complications (41.8+/-5.4) was significantly lower than that in patients without post-operative complications (46.5+/-5.3; P<0.0001). The survival in patients with higher PNI value was significantly more favourable than that in patients with lower PNI value (P=0.0001). CONCLUSIONS: Pre-operative assessment of the nutritional condition could provide predictive information for post-operative complications in patients with oesophageal carcinoma.

[Thermo-chemotherapy using low-dose CPT-11 in a patient with local recurrence of rectal cancer].

We report a case of pelvic recurrence of advanced rectal carcinoma, presenting a favorable response with a low dose (25 mg/m2) of CPT-11 (Irinotecan) combined with topical hyperthermia for relapse after treatment with 4 cycles of high-dose (100 mg/m2) CPT-11 chemotherapy alone. This combination therapy was safely carried out on an outpatient basis. The degrees of recovery of the left lower limb pain and edema, and of serum CEA reduction were comparable to those in high-dose chemotherapy alone. No significant adverse effects were encountered in the thermo-chemotherapy attempted. Since hyperthermic treatment enhances the cytotoxic effects of CPT-11 in vitro, topical hyperthermia with low-dose CPT-11 therapy may produce a response comparable to that in high-dose CPT-11 chemotherapy alone. However, an optimal dose and comparative study with other chemotherapeutic agents would be needed. This regimen may be advantageous in the maintenance of quality of life for the palliation of postoperative pelvic recurrence since this treatment can be performed on an outpatient basis.

Intra-individual differences between technetium-99m-HMPAO and technetium-99m-ECD in the normal medial temporal lobe.

UNLABELLED: Regional distributions of 99mTc-hexamethyl propyleneamine oxime (99mTc-HMPAO) and 99mTc-ethyl cysteinate dimer (99mTc-ECD) were compared in the normal brain. METHODS: Six paid, healthy volunteers (mean age 26 yr) had high-resolution neuroperfusion SPECT using both 99mTc-HMPAO and 99mTc-ECD on separate days. RESULTS: Regional distribution of the two tracers differed. Technetium-99m-HMPAO accumulated more in the thalamus, frontal lobe, temporal lobe and cerebellum than 99mTc-ECD, which accumulated more in the occipital and parietal lobes. There was a considerable difference in the accumulation of the two tracers in the medial temporal lobe. The percent accumulations of 99mTc-HMPAO and 99mTc-ECD in the medial temporal lobe compared with the mean global cerebral cortical accumulation were 93.9% +/- 2.4% and 83.1% +/- 4.1% (mean +/- s.d.), respectively. CONCLUSION: The results suggest that 99mTc-HMPAO and 99mTc-ECD require specific and separate criteria for diagnosing temporal lobe pathologies, such as dementia and temporal lobe epilepsy.

Protective effect of transfection with secretable superoxide dismutase (SOD) (a signal sequence-SOD fusion protein coding cDNA) expression vector on superoxide anion-induced cytotoxicity in vitro.

For ex vivo gene therapy, superoxide dismutase (SOD) must be secreted into the extracellular space and delivered to damaged cells. Recombinant DNA technique can be used to produce a secretory protein that is fused to a non-secretory protein and a signal peptide of another secretory protein gene. We constructed a secretable SOD eukaryotic expression vector which expresses human SOD cDNA by fusing it to the signal peptide DNA sequence of the human interleukin-2 (IL-2) gene. The ILSOD cDNA constructed by PCR-based gene expression was ligated into the multicloning site of the pRc/CMV plasmid (pRc/CMV-ILSOD). Rat lung epithelial like cells (L2 cells) were transfected with pRc/CMV-ILSOD by lipofection. The extracellular SOD activity of ILSOD-L2 cells (transfected cells with pRc/CMV-ILSOD) was 3 times as high as that of host cells. We used the xanthin (X)/xanthin oxidase (XO) system to produce superoxide anions at the extracellular space. We initially investigated the direct cytotoxicity of superoxide anions upon cells. Host and ILSOD-L2 cells were killed by using X/XO, although the sensitivity of the ILSOD-L2 cells to X/XO induced cytotoxicity was significantly decreased compared with that of host cells. The production of lipid peroxidated substances in the host in the presence of X/XO increased to about twice the control (absence of X/XO) level. However, that of ILSOD-L2 cells did not change in the presence of X/XO. Therefore, ILSOD-L2 cells were resistant to X/XO induced lipid peroxidation. These findings indicated that ILSOD gene transfection protected against direct oxidant stress by X/XO. We then investigated the effect of extracellular SOD secreted from ILSOD-L2 cells on extracellular superoxide anion induced cytotoxicity in normal cells. The conditioned media of host cells had no significant effect upon X/XO induced cytotoxicity. However, the conditioned media of ILSOD-L2 cells protected against X/XO induced cytotoxicity. Furthermore, the conditioned medium of ILSOD-L2 cells was more effective than that of host cells against the production of lipid peroxidated substances by normal cells under conditions of oxidative stress. These results indicated that non-secretable protein could be delivered to target cells by means of DNA engineering. This strategy could thus provide an ex vivo means of applying gene therapy using non-secretable proteins.

DCG-IV, a potent metabotropic glutamate receptor agonist, as an NMDA receptor agonist in the rat cortical slice.

The depolarization induced by DCG-IV, a potent agonist for Group II metabotropic glutamate receptors (Group II mGluRs), was depressed by selective antagonists for NMDA receptors in the rat cortical slice, but was not affected even by a high concentration of a selective antagonist for Group II mGluRs. DCG-IV caused depolarization more effective than NMDA in a dose-dependent manner with a threshold concentration of 3 microM in rat cortical slices, while DCG-IV was less active than NMDA in rat spinal cords. These actions should be carefully considered particularly when DCG-IV is used as an agonist for mGluRs in vivo.

L-arginine inhibits smooth muscle cell proliferation of vein graft intimal thickness in hypercholesterolemic rabbits.

OBJECTIVE: The effect of the chronic administration of L-arginine on intimal thickness and the kinetics of smooth muscle cell proliferation in autovein grafts in hypercholesterolemic rabbits were examined. METHODS: Male rabbits were fed a 1% cholesterol diet (control group) and a 1% cholesterol diet supplemented by 2.25% L-arginine HCl in drinking water (arginine group). Each group underwent reversed autologous vein bypass grafting of the left common carotid artery using the left external jugular vein. At 2 or 4 weeks after operation, intimal cell proliferation was determined by 5-bromo-2'-deoxyuridine (BrdU) incorporation and intimal thickness of the graft was measured with an ocular cytometer. At 4 weeks after operation, endothelium-dependent responses were examined by isometric tension recording. RESULTS: At 4 weeks after operation, the level of plasma arginine and citrulline are significantly higher in the arginine group (n = 7), compared with the control (n = 7). Intimal thickness in the arginine group (n = 7) was significantly reduced, compared with that of the control (n = 7). At 2 weeks after operation, the BrdU labeling index of the control (n = 5) was significantly higher than that of the arginine group (n = 5). At 4 weeks after operation, ACh caused endothelium-dependent relaxation in the arginine group (n = 4), while in the control (n = 4), ACh did not relax. CONCLUSIONS: These results suggest that smooth muscle cell proliferation of the rabbit jugular vein grafts during hypercholesterolemia occurs at an early stage after graft implantation, prior to the development of intimal thickness. Intimal thickness of vein graft during hypercholesterolemia was reduced by chronic administration of dietary L-arginine, by inhibiting smooth muscle cell proliferation. The enhancement of NO production in the blood vessel wall may therefore be useful for preventing late graft failure.

Super-early iodine-123-iodoamphetamine SPECT imaging of human primary motor cortex.

UNLABELLED: This study was designed to visualize the motor function area related to finger movements in normal human brain using super-early (first 640 sec of acquisition) [123l]iodoamphetamine ([123I]IMP) SPECT. METHODS: Seven healthy male volunteers performed paired, isolated baseline and task sessions. The task was a right thumb-to-fingers opposition task, which was loaded for the initial 11 min of the session. A high-performance, four-head SPECT camera was used. At each session, administration of 222 MBq [123I]IMP was followed by 16 serial 160-sec dynamic SPECT acquisitions. To obtain matched brain anatomical images, MRI was also performed using the same slice formation as in the SPECT study. After image reconstruction, ROIs were set on bilateral sensorimotor hand areas (SMHA), the supplementary motor area (SMA), the frontal, temporal and occipital lobes and the cerebellar hemispheres. The percent increase of ROI activity (%INC) in the task session compared with that in the baseline session was calculated in each ROI after normalization to the global brain radioactivity. RESULTS: There was significant activation of the left SMHA by the task, the amplitude of which was maximal in the initial phase of dynamic images (the super-early phase). This area was located in the left peri-central area identified on the analogous slice in the MR image. The left SMHA showed gradual and statistically significant decrease of %INC during the three phases. CONCLUSION: Super-early [123I]IMP may be used to identify the primary motor cortex and to evaluate its function in some pathological conditions.

[Studies on the Nepalese crude drugs. XVII. On the naphthalene related compounds from the root bark of Oroxylum indicum VENT].

Nine new naphthalene related compounds (I, IV, V, VII-XII) together with four known compounds (II, III, VI, XIII) were isolated from the root bark of Oroxylum indicum Vent. (Bignoniaceae), one of the Nepalese crude drugs. Their structures were determined based on chemical and physiocochemical evidence.

Inhibitory effect of xian-qing-long-tan extract on degranulation and histamine release from rat mast cells.

Xian-Qing-Long-Tang (XQLT), a Chinese medicine, is useful for treating allergic diseases. To demonstrate the anti-allergic effect of this drug we examined its effect on degranulation and histamine release from rat mast cells induced by antigen and compound 48/80. The effect on 48 h homologous passive cutaneous anaphylaxis (PCA) in rats was also studied. In the IgE antigen-antibody reaction using DNP-As, XQLT inhibited histamine release from rat mast cells, in vitro; it also inhibited 48 h rat homologous PCA reaction, in vivo. These results suggest that XQLT inhibits type 1 allergic reaction, and has effectiveness for allergic disease.

Biomedical irradiation system for boron neutron capture therapy at the Kyoto University Reactor.

Physics studies related to radiation source, spectroscopy, beam quality, dosimetry, and biomedical applications using the Kyoto University Reactor Heavy Water Facility are described. Also, described are a Nickel Mirror Neutron Guide Tube and a Super Mirror Neutron Guide Tube that are used both for the measurement of boron concentration in phantom and living tissue and for precise measurements of neutron flux in phantom in the presence of both light and heavy water. Discussed are: (1) spectrum measurements using the time of flight technique, (2) the elimination of gamma rays and fast neutrons from a thermal neutron irradiation field, (3) neutron collimation without producing secondary gamma rays, (4) precise neutron flux measurements, dose estimation, and the measurement of boron concentration in tumor and its periphery using guide tubes, (5) the dose estimation of boron-10 for the first melanoma patient, and (6) special-purpose biological irradiation equipment. Other related subjects are also described.

Excitatory action of a plant extract, stizolobic acid, in the isolated spinal cord of the rat.

Actions of stizolobic acid, stizolobinic acid and their derivatives were examined on the isolated spinal cord of the newborn rat. The responses were recorded from the ventral root. Stizolobic acid and its bromo-derivatives caused a depolarizing response in a dose-dependent manner. Stizolobinic acid was considerably less potent than stizolobic acid. Depolarizing responses to stizolobic acid and its bromo-derivatives were not affected by the existence of Mg2+ and specific N-methyl-D-aspartate (NMDA) antagonists. Kynurenate depressed responses to stizolobic acid. These results suggest that stizolobic acid is a new excitatory amino acid in the mammalian central neurons which binds preferably to other receptors than the NMDA-type receptor.

Calcium homeostasis in premature infants and treatment of early hypocalcaemia by 1,25-dihydroxycholecalciferol.

We studied calcium homeostasis and the serum calcium response to oral 1,25-dihydroxycholecalciferol [1,25 (OH)2D3] at a low pharmacological dosage of 0.1 microgram/kg daily in 14 early hypocalcaemic asymptomatic neonates. Seven hypocalcaemic neonates were not treated. In hypocalcaemic neonates serum PTH levels were normal, the urinary C-AMP response after PTH stimulation was poor and plasma 1,25 (OH)2D3 was low. Treatment with 1,25(OH)2D3 resulted in a rapid increase of serum calcium. The increase was more rapid in neonates treated with 1,25(OH)2D3 than in untreated subjects. A similar result was obtained in one of a pair of identical twins. These results suggest that a low dose of 1,25(OH)2D3 is effective in treating neonatal hypocalcaemia. However, the response was delayed for 48 h. The reason for this delay is not clear.

Effect of 1,25-dihydroxyvitamin D3 on insulin secretion: direct or mediated?

In order to clarify the role of vitamin D (D) in regulating insulin secretion, we studied the effect of long term (10 days) and short term (3 days) supplementation with D and/or calcium (Ca) on insulin secretion from the isolated, perfused pancreas of D- and Ca-deficient rats. The influence of the nutritional state induced by D deficiency was also evaluated. The long term supplementation of either D, Ca, or both restored the body weight and improved insulin secretion induced by high glucose concentration to the same extent; thus, no significant difference in insulin secretion was found between the D-only-supplemented group and the Ca-only-supplemented group. When the insulin secretion was compared in D-deplete vs. D-replete rats given the same amount of Ca, insulin secretion was significantly higher in D-replete animals, although plasma Ca levels were also higher. In short term experiments, insulin release was significantly augmented to a similar extent in D- or Ca-replete rats as compared with D- and Ca-deficient rats, despite no significant change in body weight. In a separate experiment, the pancreas from D-deficient rats was perfused with or without 1,25-dihydroxyvitamin D3 [1,25-OH)2D3] to observe its acute effect on insulin release. The perfusion with 1,25-(OH)2D3 did not affect insulin release. This result suggests that impaired insulin secretion in D-deficient rats is caused by a decrease in Ca in the body fluid and possibly by the lack of D effect on the pancreas.

[Episode secretion of LH releasing hormone and LH in peripheral plasma of women with and without ovulatory disturbances].

We studied the secretory dynamics of plasma luteinizing hormone releasing hormone (LHRH) and luteinizing hormone (LH) in 5 normal ovulatory women during the early follicular phase, and 29 cases of ovuluatory disturbances using radioimmunoassay methods. All of the normal ovulatory women demonstrated one or two pulsatile LHRH releases in 3 or 4 hours. The height of LHRH secretory spikes was observed to be between 1.4 and 9.2 pg/ml. Plasma LH episodic secretion was related to LHRH episodic secretion. In 15 out of 27 cases of of ovulatory disturbances except cases with primary ovarian dysfunction, the LH episodic secretion revealed a significant decrease in pulse frequency. In 13 out of 16 cases of ovulatory disturbances, the height of LHRH secretory spikes was not greater than 1.3 pg/ml. This study indicates that the main causes of ovulatory disturbances are decrease in LHRH and LH episodic secretion. In all cases treated with clomphene, the plasma LHRH pulse increased after treatment. But in the cases where ovulation was not induced by clomiphene citrate, the plasma LH pulse did not increase as the LHRH pulse increased.

[Regional distribution of pancreatic polypeptide-like immunoreactivity in the canine brain].

Recently many gut hormones have been found in the brain, and there is some evidence to suggest that pancreatic polypeptide-like immunoreactivity (PP-LI) is also present in the brain. Although in mammals, confirmative evidence is not yet shown. In the present paper we report the distribution and tissue localization of PP-LI in the canine brain by radio-immunoassay (RIA) and immunohistochemistry. Normal, fasted mongrel dogs were used. Brain tissue was extracted by boiling water. High concentrations of PP-LI were found in the pituitary gland (3.67 +/- 1.10 ng/g wet wt), substantia nigra (1.58 +/- 0.36 ng/g wet wt), hypothalamus (0.74 +/- 0.28 ng/g wet wt) and olfactory lobe (0.58 +/- 0.21 ng/g wet wt). PP-LI was not detectable in the frontal lobe, parietal lobe, striatum, thalamus, hippocampus, pons, cerebellum and medulla oblongata. The amounts of PP-LI in the brain were more less than the amounts of PP present in the pancreas (duodenal lobe, 29.3 +/- 1.1 microgram/g wet wt). The dilution curve of the brain tissue extracts showed parallelism with the standard curve of human and porcine PP on the RIA system. On Bio-Gel P-30 column chromatography, PP-LI from the pituitary gland and olfactory lobe eluted as a single peak coincided with highly purified bovine PP. In immunohistochemical study, PP-LI was found in the intermediate lobe and the stalk of the pituitary gland by means of anti-bovine PP antiserum. These findings of the specific regional localization suggest that PP or PP-LI may have a physiological role in the central nervous system.

The circadian rhythms of blood ionized calcium in humans.

It is well known that several hormones and minerals develop daily variation in human blood. Recently the presence of circadian rhythms of blood ionized calcium and serum phosphate concentrations in man reported (Science 213: 672-674, 1981). To clarify the difference in race and age, we examined the serum concentration of minerals such as ionized calcium, inorganic phosphate, total calcium and magnesium, and venous blood pH during 24 hours in three 31 to 40 years old Japanese males in good health. Result [1]. There was a correlation between concentration of ionized calcium and blood pH (r = -0.467 p less than 0.001), and between concentration of ionized calcium and total calcium (r = 0.366 p less than 0.005). [2]. Apparent rhythms of ionized calciums and inorganic phosphate concentrations has been noticed.

Serum calcium regulating hormones in the perinatal period.

To clarify perinatal vitamin D metabolism, we measured 25-hydroxyvitamin D (25OHD), 24,25-dihydroxyvitamin D [24,25(OH)2D], 1,25-dihydroxyvitamin D [1,25(OH)2D], calcium (Ca), phosphorus (P), parathyroid hormone (PTH), and human calcitonin (CT) in paired maternal, cord, and infant serum. Cord serum 25OHD was significantly lower than the maternal level, and cord serum 24,25(OH)2D was also significantly below the maternal concentrations. Maternal, cord, and infant serum 1,25(OH)2D, on the other hand, was significantly higher than the normal adult level. The serum PTH was low, but the CT concentration was high in the cord. Cord serum Ca and P levels were significantly higher than maternal. The reason for the elevated circulating 1,25(OH)2D level in the perinatal period is uncertain, and we speculate that the possible factors are gonadal steroids, placental lactogen, prolactin, and CT. In addition, serum 24,25(OH)2D and 1,25(OH)2D concentrations are under some control by the fetus.

Effect of dibutyryl adenosine 3',5'-monophosphate administration on plasma concentrations of 1,25-dihydroxyvitamin D in pseudohypoparathyroidism type I.

The effect of dibutyryl cAMP on plasma concentrations of 1,25-dihydroxyvitamin D [1,25-(OH)2D] was studied in two patients with pseudohypoparathyroidism (PHP) type I, five normal adults, and three normal children as controls. In normal adults, plasma 1,25-(OH)2D tended to increase 3 h after the infusion of 2.5 mg/kg dbcAMP and was significantly increased after 6 h. In normal children, plasma 1,25-(OH)2D increased 3 h after the infusion, then gradually decreased; in the patients with PHP type I, it increased greatly from 6.8 and 11.2 pg/ml to 264.6 and 128.2 pg/ml 3 h after the infusion. These results suggest that the renal mechanism for the response to parathyroid hormone is intact distal to the renal adenylate cyclase in patients with PHP type I.