Dielectric property measurement of ocular tissues up to 110 GHz using 1 mm coaxial sensor.

Measurement of the dielectric properties of ocular tissues up to 110 GHz was performed by the coaxial probe method. A coaxial sensor was fabricated to allow the measurement of small amounts of biological tissues. Four-standard calibration was applied in the dielectric property measurement to obtain more accurate data than that obtained with conventional three-standard calibration, especially at high frequencies. Novel data of the dielectric properties of several ocular tissues are presented and compared with data from the de facto database.

Polychlorinated biphenyls (PCBs) decrease the placental syncytiotrophoblast volume and increase Placental Growth Factor (PlGF) in the placenta of normal pregnancy.

INTRODUCTION: Polychlorinated biphenyls (PCBs) are a class of biologically active, highly stable compounds. Exposure risks include consumption of fatty fish, meat, dairy products and human breast milk, as well as environmental and occupational settings. Numerous reports have described PCB-dependent adverse effects on human fetal growth, including increased risk for IUGR, changes in endocrine function and hormone metabolism, and immunosuppressive and neurological deficits. Here we test the prediction that in utero PCB exposure adversely effects placental morphology, potentially leading to placental insufficiency en route to fetal growth restriction. METHODS: PCB homologs (10) were measured in the maternal and fetal blood of a small cohort of normotensive pregnancies (22) by gas chromatography-mass spectrometry. PCB levels were compared with angiogenesis associated proteins Placental Growth Factor (PlGF) and sFlt-1, determined by ELISA, and the total estimated syncytiotrophoblast (ST) volume. RESULTS: Significant associations between PCB exposure and both PlGF and ST volume were identified. DISCUSSION: PCB effects on placenta morphology and predicted function are discussed. CONCLUSION: These results demonstrate that the human placenta, including ST, is a target of PCB toxicity, and that current environmental PCB exposure levels are a risk to reproductive health.

The soleus late response elicited by transcranial magnetic stimulation reflects agonist-antagonist postural adjustment in the lower limbs.

OBJECTIVES: We studied the origin and underlying mechanism of the soleus late response (SLR) at a mean latency of 90 ms following transcranial magnetic stimulation. METHODS: The soleus primary response (SPR) and SLR were recorded from the soleus (SOL) muscle in 27 normal subjects under various conditions using a double-cone coil. We also tested 28 patients demonstrating neurological disorders with postural disturbance. RESULTS: The amplitude of the SPR gradually increased and its latency gradually decreased against the voluntary contraction (0-80%) of the tibialis anterior (TA) muscle. In contrast, the SLR amplitude was the greatest at a 20% TA contraction while the SLR latency was the shortest at a 40% TA contraction. The preactivation of SOL enhanced the SPR response but did not evoke the SLR. The SPR amplitude was significantly augmented while standing, however, the SLR amplitude tended to decrease. The SLR was never obtained following the stimulation of the brainstem, lumbar roots and peroneal nerve. The SLR was abnormal in patients with cerebellar ataxia and Parkinson's disease while the SPR was normal. CONCLUSIONS: A lack of any correlation between the SPR and SLR suggests that the SLR does not originate in the corticospinal tract. The SLR may thus be a polysynaptic response related to the postural control of the agonist and antagonist organization between the TA and SOL.

[Comparison of epidural anesthesia and general anesthesia for patients with bronchial asthma].

We prospectively investigated the incidence of asthmatic attacks in 94 patients (1.5%) who were diagnosed as definite asthma. We separated the patients into three groups: epidural anesthesia (n = 10) including combined spinal/epidural anesthesia (n = 7), combined epidural and general anesthesia (n = 23), and general anesthesia (n = 54). General anesthesia was induced with propofol or midazolam and maintained with N2O and O2 with sevoflurane in adults. Patients who underwent epidural anesthesia and combined spinal and epidural anesthesia showed no asthmatic attacks. The incidence of bronchospasm with combined epidural and general anesthesia was 2/23. The incidence of bronchospasm with general anesthesia was 4/54. Bronchoconstriction occurred after tracheal intubation in 5 patients except in one patient, in whom it occurred after induction of anesthesia with midazolam. All episodes of bronchospasm in the operative period were treated successfully. The frequency of bronchospasm did not depend on the severity of asthmatic symptoms or the chronic use of bronchodilators before operation. These findings suggest that tracheal intubation, not the choice of anesthetic, plays an important role in the pathogenesis of bronchospasm.

Expression and transcriptional regulation of the human alpha1, 3-fucosyltransferase 4 (FUT4) gene in myeloid and colon adenocarcinoma cell lines.

In fucosyltransferase genes, mRNA expression is regulated in a cell-type-specific manner. The expression level of human fucosyltransferase 4 (FUT4) mRNA is high in both colon adenocarcinoma and myeloid cell lines. We will demonstrate here cell-specific expression and transcriptional regulation of the FUT4 gene. FUT4 has two different transcription initiation sites that respectively produce long- and short-form mRNAs. To determine the major FUT4 transcript in colon adenocarcinoma and myeloid cell lines, we analyzed the transcriptional starting sites of the FUT4 gene in myeloid and colon adenocarcinoma cell lines, using 5'-RACE, RT-PCR, and luciferase analysis. The results suggested that the expression level of short-form mRNA is higher than the long-form transcript in the colon adenocarcinoma cell lines and that the expression level of long-form mRNA is higher than the short-form transcript in the myeloid cell lines. Using a luciferase assay, we identified a functional DNA portion within FUT4 genomic DNA that confers a colon adenocarcinoma cell line-specific enhancer, located in nucleotide number (nt) -256 to -44, and a myeloid cell line-specific enhancer, located in nt -686 to -582. The present results suggest that these elements play a critical role in the colon adenocarcinoma and leukemia cell-specific transcriptional regulation of the FUT4 gene.

Differential temporal coding of the vibratory sense in the hand and foot in man.

OBJECTIVE: We studied the difference in the temporal tuning function of the vibratory senses between the hand and foot in man by using steady-state somatosensory evoked potentials (S-SEPs) to vibratory stimulation. METHODS: Vibratory stimuli were applied to the palm and sole, and the S-SEPs were then recorded in 8 normal subjects. A total of 200 responses were recorded from 4 electrodes including the ipsi-and contralateral somatosensory areas of the hand and foot. The amplitude of the first harmonic component (1F) was obtained by a Fourier analysis. The effect of modulation frequency (17-30 Hz) on the 1F at a stimulus intensity of 0.05 N was studied. RESULTS: The amplitudes of the S-SEPs were the greatest in the contralateral hand and foot areas. The mean 1F amplitudes of the palm S-SEPs as a function of the modulation frequency showed a narrow tuning curve with a peak near 21 Hz while those of the sole demonstrated a broad tuning curve. CONCLUSION: Our results suggest the differential temporal coding of the vibratory sense in the hand and foot areas of the somatosensory cortex in man. This is probably caused by the different characteristics in the receptors situated in the hand and foot.

Motor and somatosensory evoked potential findings in HTLV-I associated myelopathy.

The central motor and sensory conduction times were measured using the motor and somatosensory evoked potentials in 21 patients with HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP) to evaluate the functions of the corticospinal tract and posterior column. The control subjects were closely matched for gender, age and height with the patients in the central sensory conduction time (CSCT) and central motor conduction time (CMCT) studies. An abnormal upper limb (UL) CMCT was present in six of 34 limbs (17.6%) while the lower limb (LL) CMCT was abnormal in 31 of 42 limbs (73.8%). No patients had an abnormal UL CSCT while the LL CSCT was abnormal in 10 of 32 limbs (31.3%). The frequency of abnormal LL CMCT was significantly higher than that for an abnormal LL CSCT. The duration of the disease and the disability score did not significantly influence the evoked potential findings. These results indicate that major lesions of the spinal cord in HAM/TSP patients tend to be localized more in the descending corticospinal pathways than in the ascending posterior columns at the thoracic spinal cord level. This finding also closely agrees with the clinico-pathological findings of HAM/TSP.

Idiopathic cortical myoclonus restricted to the lower limbs: correlation between MEPs and 99mTc-ECD single photon emission computed tomography activation study.

We report a 63-year-old woman with cortical reflex myoclonus restricted to the bilateral lower limbs. Somatosensory evoked cortical potentials to posterior tibial nerve stimulation were enlarged with C-responses. Jerk-locked back averaging of the EEG identified a cortical spike related to myoclonic jerks. Motor evoked potentials recorded from the abductor hallucis muscle showed an exaggerated late response. These findings suggest hyperexcitability of the sensorimotor cortex. 99mTc-ECD single photon emission computed tomography (SPECT) after stimulation of the posterior tibial nerve showed increased perfusion in the contralateral peri-Rolandic area which corresponded to the hyperexcitable region. A SPECT activation study as well as MEPs therefore can be employed to determine the hyperexcitable region in cortical myoclonus.

Strength of base materials.

PURPOSE: To compare the punch resistance of VariGlass and Vitrebond. MATERIALS AND METHODS: Discs measuring 1.4 cm in diameter and 1.5 mm thick of VariGlass (VG) and Vitrebond (VT) light-activated lining materials, were prepared and submitted to punch testing in a universal testing machine at 7 minutes, 30 minutes and 24 hours after mixing. RESULTS: VG showed higher resistance to punch testing than the VT in the three periods evaluated (P< 0.01). The results were further compared to previous data obtained from three calcium hydroxide lining cements which gave much lower values than VG and VT (P< 0.01).

Depressive and negative symptoms in major psychiatric disorders.

Among 193 inpatients with Research Diagnostic Criteria (RDC) major psychiatric disorders, the scores in Hamilton's Rating Scale for Depression (HRSD) were higher among those patients with RDC schizoaffective disorder depressed type and major depressive disorder, whereas the scores in the Scale for Assessment of Negative Symptoms (SANS) were higher among patients with these two disorders, as well as those with RDC nonaffective psychoses (schizophrenia and unspecified functional psychosis). The HRSD and SANS items were factor-analyzed, yielding nine factors that discriminated depressive and negative symptoms. These findings suggest that although depressive and negative symptoms frequently coexist, they constitute discrete syndromes.

Cooperative binding of primycin and gramicidin on erythrocyte membranes. A cation transport study.

In this paper the authors present a comparative study of the actions of the antibiotics primycin and gramicidin on the erythrocyte membrane permeability. It has been found that both antibiotics have a nonlinear effect on the membrane permeability. Above a threshold antibiotic concentration, which is characteristic of the type of the antibiotic, the cation permeability of the erythrocyte membranes increases sharply. In the range of nonlinearity the transport-kinetic curves level off before achieving the equilibrium radioactive ion distribution between the extra- and intracellular spaces. A stochastic model of the cooperative and aspecific incorporation of antibiotic molecules into the membrane explains the experimental findings. The authors conclude that membrane permeability increases at the places where two or more antibiotic molecules form aggregates in the membrane.

Establishment of normal values in adults for zinc protoporphyrin (ZPP) using hematofluorometer: correlation with normal blood lead values.

Zinc protoporphyrin (ZPP) values were analyzed with a hematofluorometer on 395 non-occupationally lead exposed subjects. Blood lead (B-Pb) determinations were concurrently carried out with an extraction procedure using flameless atomic absorption method. Applying Hoffman's Statistical Analysis with a logarithmic transformation, a normal range for ZPP (a mean of 23 microgram/dL) was established with 40 microgram ZPP/dL on the upper limit of the 95% probability range. A value of 54 microgram ZPP/dL has been found to be a suitable cutoff value above which one generally finds B-Pb values greater than 40 microgram/dL. For B-Pb values (less than 40 microgram/dL) and ZPP values in our normal range, there was essentially no correlation. However, for elevated values of both, a correlation coefficient of 0.87 was found for log ZZP versus B-Pb. ZPP values for males appeared to increase with increasing age.