Interstitial impurity-induced magnetism in α-PbO surface.

We have investigated the effects of 3d transition metal (TM) and non-magnetic interstitial impurities in α-PbO (0 0 1) surface using ab-initio calculations. The calculated impurity-induced magnetic moments are 2.25 µB, 3.11 µB and 0.94 µB for Fe, Mn and Pb interstitials respectively. In the bonding process, TM's lower energy lying d(z2) states form overlaps with nearest neighbour oxygen atoms' p(z) states, with other non-bonding spin split d states situated near or at the Fermi level. These spin split orbitals introduce spin polarised p impurity states of oxygen atoms near the surface.

Phosphate as a limiting factor for the cell division of tobacco BY-2 cells.

The re-addition of phosphate to tobacco BY-2 cells deprived of phosphate for 3 d induced cells to semi-synchronously re-enter the cell cycle from a static state. Though the addition of auxin to auxin-starved tobacco BY-2 cells also induced cell division (Ishida et al. 1993), some major differences were observed between these two systems. BY-2 cells lost the ability to re-enter the cell cycle after prolonged periods of auxin deprivation, but in contrast retained this ability after longer periods in the absence of phosphate. By differential cDNA screening we identified a phosphate-induced gene phi-1. phi-1 was rapidly induced by the addition of phosphate with transcript levels starting to decrease by the start of DNA synthesis. phi-1 does not share any significant homology with any gene with known functions over its full length. However, the N-terminus shared some homology with plasma membrane ATPases suggesting that it may be involved in some process of phosphorylation. Immunolocalization of the phi-1 gene product revealed that it rapidly accumulated in the cytoplasm prior to the start of plastid and nuclear DNA synthesis. These results are discussed in relation to the role of phosphate in inducing plant cell division.

CT scanning of bronchioloalveolar carcinoma: specific appearances.

We reviewed CT scans in 38 cases with pathologically proved bronchioloalveolar carcinoma. CT revealed three CT patterns: solitary, pneumonic and diffuse forms. The solitary pattern (22 patients) had a high percentage of air bronchograms (95%), pleural indentation (77%) and spiculation (68%). The pneumonia-like pattern (16 lesions in 10 patients) had air bronchograms in all cases (100%), low attenuation (88%) and protrusion of interlobar fissures (63%). The diffuse form (six patients) had 2 or 3 mm diffuse small nodules scattered throughout the entire lung. CT of bronchioloalveolar carcinoma revealed many findings and was useful in recognizing the tumor distribution and extent. We conclude that CT is helpful for the diagnosis and evaluation of bronchioloalveolar carcinoma.

[Detection of cortical infarcts in brain MR imaging: feasibility of short-TR-T2-weighted imaging using a fast spin echo sequence].

MRI of the brain using a fast SE sequence is often performed with a TR above 5000 msec, so there is a tendency for the signal of CSF to become too high. However, when cerebral atrophy is marked, small lesions of the brain parenchyma can be hard to detect. Therefore, we examined short-TR-T2-weighted images using a fast spin echo sequence. The 58 subjects included 33 men and 25 women, and cortical infarction was detected in five of them. On the short-TR-T2WI sequences, the infarct lesions were imaged as areas of higher signal intensity than cerebrospinal fluid, the signal of which was reduced. In cortical infarction cases, fluid-attenuated inversion recovery (FLAIR) images can detect the lesion more easily, but FLAIR sequences cannot be obtained with all MR equipment. Short-TR-T2WI, which readily yields images comparable to those of FLAIR, is an useful method.

[CT evaluation of the pelvic cavity after total cystectomy].

CT scans were performed 40 times in 28 postcystectomy patients to identify the type and location of tumor recurrence. Sixteen patients showed tumor recurrence. Patients without recurrence showed a complete symmetric pelvis and a thin string that looked like an operation scar. Cutaneous ureterostomy showed small tube-like structures, and ileal conduit looked like herniation of the ileum. Cases with recurrent tumors were divided into 3 patterns, 1) pelvic abscess recurrence, 2) anterior abdominal wall thickening, 3) pelvic lateral wall thickening, and combinations of these types. The abscess-recurrence type often showed air within the mass or a fuzzy contour that could not be differentiated from true inflammatory abscess. Anterior abdominal wall thickening was usually accompanied with abscess-type recurrence and appeared as thickening of the operation scar. Lateral wall thickening was usually seen at the site of the obturator internus muscle or obturator node. Patients without recurrence had no complaints except for two who had ileus. All patients with recurrence except one had complaints of pain, abnormal secretion, or a palpable mass. Because all patients with recurrence already had a relatively large tumor at the time of CT, routine follow-up CT is recommended even if the patient has no complaints.

Cerebrocerebellar relationships in normal subjects and patients with dementia of the Alzheimer type: a SPECT study.

The relationships between blood flow in the cerebrum and the cerebellum was investigated in 21 normal subjects and 21 patients with dementia of the Alzheimer type (DAT). In normal subjects, only asymmetry in the frontal cortical blood flow was significantly correlated with asymmetry in the contralateral cerebellar blood flow. However, a significant correlation between asymmetry in the cerebral cortical blood flow in many areas and the blood flow in the contralateral cerebellum in DAT patients was observed. These results suggest the existence of a functional relationship between the cerebrum and the cerebellum in both normal and DAT groups, mediated by neuronal mechanisms through crossed fiber pathways. However, there are regional differences in the cerebrocerebellar relationship in normal resting and pathological states.

[123I-IMP SPECT study on patients with amnestic syndrome].

Regional cerebral blood flow was studied using single photon emission CT (SPECT) with 123I-IMP to elucidate the pathophysiology of amnesia. Four patients with amnestic syndrome diagnosed by DSM-III-R criteria were investigated. SPECT images demonstrated definite hypoperfusion of the temporoparietal lobe and relative sparing of motor-sensory and occipital cortices in two out of four patients. Since these abnormalities of regional cerebral blood flow have been considered to be characteristic findings in dementia of the Alzheimer type, two patients with temporoparietal hypoperfusion are suggested to manifest the early stage of dementia of the Alzheimer type. Our observations suggest that 123I-IMP SPECT is an useful modality in the diagnosis of the early stage of dementia of the Alzheimer type, especially in patients with only memory impairment.

[Asymmetry of cerebral blood flow in patients with senile dementia of Alzheimer type by SPECT using I-123 IMP].

Regional cerebral blood flow (rCBF) was determined by single photon emission CT (SPECT) with N-isopropyl-p-[123I]iodoamphetamine in 22 patients with clinically diagnosed senile dementia of Alzheimer type (SDAT) and in 18 age matched controls. We calculated asymmetry indices (AIs) of rCBF for matched right-left regions of interest. rCBF of parietal lobe in SDAT patients was significantly most laterally asymmetrical, but the least in occipital lobe. Lateral asymmetry of rCBF in SDAT patients correlated with asymmetry of language and visuospatial functions; decreased rCBF in the left parietal lobe was associated with language dysfunction, and that in the right parietal lobe, with visuospatial dysfunction. Furthermore cerebellar AIs correlated negatively with those of the cerebral hemisphere and lower frontal region in SDAT patients. The results demonstrate that rCBF measurement by 123I-IMP SPECT is useful to detect lateral asymmetry in reduction of rCBF in SDAT.

[Malignant ovarian tumor invasion to the uterus and bladder: assessment with magnetic resonance imaging].

Twenty-nine patients with ovarian malignant tumor were studied by means of magnetic resonance (MR) imaging. The findings were compared with surgical findings concerning tumor invasion to the bladder and to the uterus. The bladder invasion was evaluated with MRI and classified as follows: (1) Huge amount of fat, colon or small intestine between the tumor and the bladder. (2) Thin fat layer between the bladder and the tumor, (3) No fat layer, and the bladder was smoothly compressed by the tumor, (4) No fat layer with local deformity of the bladder caused by the tumor existed, or tumor protruded into the bladder. In group (4), 4 of 5 cases were proved to have bladder invasion. However in group (3), half of the 14 cases showed bladder invasion and the others showed no invasion. Criteria used in MRI analysis of uterine invasion was as follows: (1) Fat layer between the uterus and the tumor, (2) Fat layer between the tumor and the bladder, and the uterine contour was indistinct, (3) No fat layer and deformity of the uterus was apparent. In group (3), many cases showed uterine invasion, but 4 cases out of 12 cases did not. In the group (2), 3 out of 11 cases showed uterine invasion. The diagnostic ability of uterine invasion was not as accurate as in cases of the bladder invasion. The MRI sagittal plane can directly show the relationship between the uterus, the bladder and tumor, so that diagnosis of tumor invasion by MRI is superior to CT. However MRI could not differentiate between adhesion and invasion.

[Clinical efficacy of Z-100 for the treatment of leukopenia caused by radiotherapy--a multi-center double-blind comparative study with inosine].

The clinical usefulness and the optimal dose of Z-100 for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated in a double-blind study comparing 20 micrograms and 30 micrograms injections of Z-100 and inosine (Z-20, Z-30 and IN group, respectively). The effective rate according to the evaluation by the attending physicians was 67.4%, 79.1% and 48.9% in the Z-30, Z-20 and IN groups, respectively, with a significantly higher efficacy rate for the Z-20 group than for the IN group. The frequency of adverse reactions was 14.3%, 3.9% and 5.6% in the Z-30, Z-20 and IN groups, respectively, with the highest rate in the Z-30 group, but there was no significant difference among the three groups. The useful rate based on total evaluation considering the effective rate and the safety profile in each group was 60.8%, 77.3% and 46.8% in the Z-30, Z-20 and IN groups, respectively, with the highest rate in the Z-20 group showing significant difference from that in the IN group. The above data confirmed the clinical usefulness of Z-100 and suggested that the optimal dose was 20 micrograms twice weekly for Z-100.

[Clinical efficacy of Z-100 for the treatment of leukopenia caused by radiotherapy--a multi-center double-blind comparative study with L-cysteine].

The clinical usefulness of Z-100 (Z group) for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated by comparing it with that of L-cysteine (L group) by the double-blind method. For 178 complete cases, there were no significant differences in the time-course of the WBC during radiotherapy between the two group. However, for cases with a large field of irradiation (15 X 15 cm = 225 cm2), the mean WBC count in the L group decreased more than that in the Z group. The Z group showed comparable or superior efficacy for the treatment of leukopenia in the L group although there were no significant differences. Adverse reactions were observed in 5.66% and 2.94% in the Z and L groups, respectively, without any significant difference between the groups. The utility rate, useful or better, was 73.9% and 69.2% in the Z and L groups, respectively, showing a slightly higher rate in the Z group than in the L group, although the difference between the two groups was not significant. These results confirmed that Z-100 has comparable or superior efficacy to L-cysteine for the treatment of leukopenia caused by large field radiotherapy for malignant tumors.

[An early clinical study of Z-100 in leukopenia caused by radiotherapy].

The clinical efficacy of Z-100 for the treatment of leukopenia caused by radiotherapy for malignant tumors was evaluated in an early clinical study using three doses, 2, 10 and 20 micrograms. According to the evaluation by investigators and time-course of WBC, the highest effective rate was achieved by 20 micrograms. Adverse reactions occurred in all groups, but there were no serious or clinically relevant reactions. These results suggested that Z-100 is clinically useful for the treatment of leukopenia caused by radiotherapy.

[Effect of pulsed electromagnetic fields (PEMF) on human periodontal ligament in vitro. Alterations of intracellular Ca2+].

The concept of orthodontic tooth movement is based on the hypothesis that teeth move as a result of the biological response of periodontal tissues to the mechanical forces applied. There is a widely held hypothesis that mechanical stress generates an electrical signal which sets in motion the subsequent events, as in bone exposed to mechanical forces electrical currents are produced affect bone growth and remodeling. This implies a transduction mechanism which translates the electrical signal into a biochemical message, recognizable by the cellular machine. This study is aimed at the identification of the message and the investigation of its control. In fact, the effect of Pulsed Electromagnetic Fields (PEMF) on the intracellular second messenger, cytoplasmic Ca2+ in Human Periodontal Ligament Fibroblasts (HPLF) was investigated. The resting intracellular ionized calcium concentration ([Ca+2]i) of HPLF cells was 232.7 +/- 25.0 nM, and with PEMF [Ca2+]i increased from 12 hrs to 499.0 +/- 115.5 nM up to 12 hrs, then reached to a steady level through 24 hrs. The PEMF were also found to decrease the responses towards epidermal growth factor (EGF) and serum, when the degree of response was based on the intracellular Ca2+ transient. These effects of PEMF were mimicked by 12-0-tetradecanoyl phorbol 13-acetate (TPA), a potent activator of protein kinase C. Some reports have suggested that fibroblasts of the periodontal ligament contain high alkaline phosphatase (ALPase) activity as much as osteoblast. Since similar results concerning the [Ca2+]i were obtained in osteoblast (OB)-like cells, this experiment also supports the hypothesis that fibroblasts of periodontal ligament have osteoblastic features.

[The accuracy of CT and tumor markers in the detection of a recurrent ovarian carcinoma].

Twenty-three patients previously diagnosed as having ovarian cancer were examined with both serum tumor markers (CA 125, CA 19-9, TPA, IAP, AFP) and a pelvic CT scan. The tumor markers predict the clinical outcome more accurately than the CT scan. Further, the tumor markers showed a clear correlation with the clinical course. But in one case, however, the tumor markers were seen to reduce below the normal level from chemotherapy, while the CT scan showed a tumor mass. Thus, both, a CT scan and tumor marker assays are felt to be indispensable for detecting the recurrence of an ovarian cancer.

[Combined radiotherapy and resection in carcinoma of the lung].

To evaluate the therapeutic effect of surgery combined with radiotherapy in lung cancer, 385 operative cases, and 308 received combined treatment, were analyzed. The 5-year survival rate of T3 cases among pTNM-stage III cases undergoing surgery was 2.4% (1/42), while that of cases receiving combined radiotherapy was 18.9% (14/74), which showed some effectiveness. The 5 year survival rate of N2 (n3), operation only cases and combined treatment cases were 5.3% (2/38), and 8.9% (8/90), respectively. Long-term survival among cases of extensive mediastinal metastasis (# 1-9) confirmed the effect of combined therapy. Combined therapy effect was recognized in squamous cell carcinoma.