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Z Zhao

Publications and source records attributed to Z Zhao.

At least 181 records · Page 10Linked to original sources
PubMed1998

Interaction of 2-n-heptyl-4-hydroxyquinoline-N-oxide with dimethyl sulfoxide reductase of Escherichia coli.

We have studied the interaction of the menaquinol analog 2-n-heptyl-4-hydroxyquinoline-N-oxide (HOQNO) with dimethyl sulfoxide reductase (DmsABC) and the effect of a mutation in the DmsC subunit (DmsABCH65R) using fluorescence titration and stopped-flow methods. The titration data show that the HOQNO fluorescence is quenched when HOQNO binds to DmsABC. The binding stoichiometry is determined to be about 1:1. The mutant DmsABCH65R blocks HOQNO binding to the protein. It is therefore proposed that there is one high-affinity HOQNO binding site per DmsABC molecule located in the DmsC subunit. Stopped-flow kinetic studies show that the interaction can be described by a two-step equilibrium model, a fast bimolecular step followed by a slow unimolecular step. The quenching of HOQNO fluorescence occurs in the bimolecular step. The rates for the forward and reverse reaction of the first equilibrium are determined to be k1 = (3.9 +/- 0.3) x 10(5) M-1 s-1 and k2 = 0. 10 +/- 0.01 s-1, respectively. The dissociation constant for the first equilibrium, Kd1 = k2/k1, is calculated to be about 260 nM. The upper limit of the overall dissociation constant is estimated to be 6 nM.

Escherichia coli↗
PubMed1998

How the presence of three iron binding sites affects the iron storage function of the ferritin (EcFtnA) of Escherichia coli.

The iron storage proteins, ferritins, are found in all organisms which use iron. Here iron storage processes in the Escherichia coli ferritin (EcFtnA) are compared with those in human H-type ferritin (HuHF). Both proteins contain dinuclear iron centres that enable the rapid oxidation of 2 Fe(II) by O2. The presence of a third iron binding site in EcFtnA, although not essential for fast oxidation, causes the O2/Fe ratio to increase from 2 to 3-4. In EcFtnA the rate of iron oxidation falls markedly after the oxidation of 48 Fe(II) atoms/molecule probably because some of it remains at the oxidation site. However a compensatory physiological advantage is conferred because this iron is more readily available to meet the cell's needs.

Amino Acid Sequence↗
PubMed1998

Mechanism of phosphatidylinositol-specific phospholipase C: a unified view of the mechanism of catalysis.

The mechanism of phosphatidylinositol-specific phospholipase C (PI-PLC) has been suggested to resemble that of ribonuclease A. The goal of this work is to rigorously evaluate the mechanism of PI-PLC from Bacillus thuringiensis by examining the functional and structural roles of His-32 and His-82, along with the two nearby residues Asp-274 and Asp-33 (which form a hydrogen bond with His-32 and His-82, respectively), using site-directed mutagenesis. In all, twelve mutants were constructed, which, except D274E, showed little structural perturbation on the basis of 1D NMR and 2D NOESY analyses. The H32A, H32N, H32Q, H82A, H82N, H82Q, H82D, and D274A mutants showed a 10(4)-10(5)-fold decrease in specific activity toward phosphatidylinositol; the D274N, D33A, and D33N mutants retained 0. 1-1% activity, whereas the D274E mutant retained 13% activity. Steady-state kinetic analysis of mutants using (2R)-1, 2-dipalmitoyloxypropane-3-(thiophospho-1d-myo-inositol) (DPsPI) as a substrate generally agreed well with the specific activity toward phosphatidylinositol. The results suggest a mechanism in which His-32 functions as a general base to abstract the proton from 2-OH and facilitates the attack of the deprotonated 2-oxygen on the phosphorus atom. This general base function is augmented by the carboxylate group of Asp-274 which forms a diad with His-32. The H82A and D33A mutants showed an unusually high activity with substrates featuring low pKa leaving groups, such as DPsPI and p-nitrophenyl inositol phosphate (NPIPs). These results suggest that His-82 functions as the general acid with assistance from Asp-33, facilitating the departure of the leaving group by protonation of the glycerol O3 oxygen. The Bronsted coefficients obtained for the WT and the D33N mutant indicate a high degree of proton transfer to the leaving group and further underscore the "helper" function of Asp-33. The complete mechanism also includes activation of the phosphate group toward nucleophilic attack by a hydrogen bond between Arg-69 and a nonbridging oxygen atom. The overall mechanism can be described as "complex" general acid-general base since three elements are required for efficient catalysis.

Alcohols↗
PubMed1998

Cloning and sequencing of cDNA encoding the LS-12 antifreeze protein in the longhorn sculpin, Myoxocephalus octodecimspinosis.

cDNA coding for an antifreeze protein (LS-12) in the longhorn sculpin, Myoxocephalus octodecimspinosis, was prepared from liver mRNA using reverse transcriptase-polymerase chain reaction coupled with 3' and 5' RACE procedures. This cDNA contains 609 base pairs, including a 384-bp open reading frame which codes for a 128-residue LS-12 precursor protein. The predicted amino acid sequence of the mature LS-12 corresponds exactly to the amino acid sequence obtained from Edman degradation [G. Deng, D.W. Andrews, R.A. Laursen, FEBS Lett., 402, 1997, pp. 17-20]. The 20 residues preceding mature LS-12 are predicted to be a signal sequence, which is presumably cleaved off before the mature, 108-residue protein is secreted into the circulatory system. This is the first report of a cDNA sequence from M. octodecimspinosis.

Amino Acid Sequence↗
PubMed1998

Frequent gene conversion between human red and green opsin genes.

To study the evolution of human X-linked red and green opsin genes, genomic sequences in large regions of the two genes were compared. The divergences in introns 3, 4, and 5 and the 3' flanking sequence of the two genes are significantly lower than those in exons 4 and 5. The homogenization mechanism of introns and the 3' flanking sequence of human red and green opsin genes is probably gene conversion, which also occurred in exons 1 and 6. At least one gene conversion event occurred in each of three regions (1, 3, and 5) in the sequences compared. In conclusion, gene conversion has occurred frequently between human red and green opsin genes, but exons 2, 3, 4, and 5 have been maintained distinct between the two genes by natural selection.

DNA↗
PubMed1998

Expression of HNK-1 carbohydrate and its binding protein, SBP-1, in apposing cell surfaces in cerebral cortex and cerebellum.

Sulfoglucuronyl carbohydrate is the terminal moiety of neolacto-oligosaccharides, expressed on several glycoproteins of the immunoglobulin superfamily involved in cell-cell recognition and on two glycolipids. Sulfoglucuronyl carbohydrate is temporally and spatially regulated in the developing nervous system. It appears to be involved in neural cell recognition and in cell adhesion processes through its interaction with specific proteins on cell surfaces. Previously we have characterized a specific sulfoglucuronyl carbohydrate-binding protein in rat brain. Sulfoglucuronyl carbohydrate binding protein-1 is structurally similar to a 30,000 mol. wt adhesive and neurite outgrowth promoting protein amphoterin [Rauvala and Pihlaskari (1987) J. biol. Chem. 262, p. 16,625]. The pattern of expression of sulfoglucuronyl carbohydrate binding protein-1 in developing rat nervous system was studied to understand the significance of its interaction with sulfoglucuronyl carbohydrate-bearing molecules. Biochemical analyses showed that the expression of sulfoglucuronyl carbohydrate binding protein-1 was developmentally regulated similarly to sulfoglucuronyl carbohydrate. Immunocytochemical localization of sulfoglucuronyl carbohydrate binding protein-1 and sulfoglucuronyl carbohydrate was performed by bright-field and fluorescent confocal laser scanning microscopy. In postnatal day 7 rat cerebellum, sulfoglucuronyl carbohydrate binding protein-1 was primarily associated with neurons of the external and internal granule cell layers. The sulfoglucuronyl carbohydrate binding protein-1 immunoreactivity was absent in Purkinje cell bodies and their dendrites in the molecular layer, as well as in Bergmann glial fibres and in white matter. In contrast, sulfoglucuronyl carbohydrate (reactive with HNK-1 antibody) was localized in processes surrounding granule neurons in the internal granule cell layer. Sulfoglucuronyl carbohydrate was also expressed in Purkinje neurons and their dendrites in the molecular layer and their axonal processes in the white matter. To a lesser extent Bergmann glial fibres were also positive for sulfoglucuronyl carbohydrate. In the cerebral cortex, at embryonic day 21, sulfoglucuronyl carbohydrate binding protein-1 was mainly observed in immature neurons of the cortical plate and subplate and dividing cells near the ventricular zone. Whereas, sulfoglucuronyl carbohydrate was strongly expressed in the fibres of the subplate and marginal zone. Sulfoglucuronyl carbohydrate was also found in the processes surrounding the sulfoglucuronyl carbohydrate binding protein-1-expressing neuronal cell bodies in the cortical plate and in ventricular zone. The specific localization of sulfoglucuronyl carbohydrate binding protein- in cerebellar granule neurons and neurons of the cerebral cortex was also confirmed by immunocytochemistry of the dissociated tissue cell cultures. The complementary localization of sulfoglucuronyl carbohydrate and sulfoglucuronyl carbohydrate binding protein-1, both in cerebral cortex and cerebellum, in apposing cellular structures indicate possible interaction between the two and signalling during the process of cell migration and arrest of migration.

Animals↗
PubMed1998

Rat liver microsomal enzyme catalyzed oxidation of 1-cyclopropyl-4-phenyl-1,2,3,6-tetrahydropyridine.

NADPH supplemented rat liver microsomal enzyme preparations catalyze the conversion of 1-cyclopropyl4-phenyl-1,2,3,6-tetrahydropyridine to the p-hydroxyphenyl (low yield), descyclopropyl (high yield) and 2,3-dihydropyridinium and, subsequently, pyridinium (intermediary yield) metabolites. When the methine proton of the cyclopropyl group was replaced with a deuteron, a normal deuterium isotope effect (1.4) was observed on the formation of the decyclopropylated metabolite and an inverse isotope effect (0.6) on the dihydropyridinium metabolite. A larger deuterium isotope effect (3.6) was observed on the ring alpha-carbon oxidation pathway with the 2,2,6,6-d4 analogue as substrate. These results and the observation that the ratios of the rates of these two alpha-carbon oxidation pathways are independent of initial substrate concentrations suggest that both pathways are catalyzed by the same active site of one form of P450. These transformations are discussed in terms of metabolic pathways that have been proposed for the cytochrome P450 catalyzed alpha-carbon oxidation of amines.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1998

Gland atrophy following retrograde injection of methyl violet as a treatment in chronic obstructive parotitis.

OBJECTIVE: The purpose of this study was to evaluate the clinical effectiveness of retrograde injection of 1% methyl violet as a treatment for chronic obstructive parotitis. STUDY DESIGN: Sixteen patients with chronic obstructive parotitis were treated with retrograde injection of 1% methyl violet. Pretreatment evaluation and assessment of the treatment effect were performed by clinical and imaging methods, including sialography and sonography of the treated glands. RESULTS: Clinical symptoms following treatment included initial acute swelling and then a decrease in parotid swellings; the final outcome was a clinical cure of the affected glands characterized by disappearance of all symptoms, absence of secretion, and complete obliteration of the main duct orifice. Posttreatment imaging showed total atrophy of the diseased glands. CONCLUSION: Retrograde injection of 1% methyl violet caused total atrophy of the diseased glands and brought about complete relief in all 16 patients, with no detectable side effects.

Adolescent↗
PubMed1998

NAGLU mutations underlying Sanfilippo syndrome type B.

Sanfilippo syndrome type B (mucopolysaccharidosis III B) is a rare autosomal recessive disease caused by deficiency of alpha-N-acetylglucosaminidase, one of the enzymes required for the lysosomal degradation of heparan sulfate. The gene for this enzyme, NAGLU, recently was isolated, and several mutations were characterized. We have identified, in amplified exons from nine fibroblast cell lines derived from Sanfilippo syndrome type B patients, 10 additional mutations: Y92H, P115S, Y140C, E153K, R203X, 650insC, 901delAA, P358L, A664V, and L682R. Four of these mutations were found in homozygosity, and only two were seen in more than one cell line. Thus, Sanfilippo syndrome type B shows extensive molecular heterogeneity. Stable transfection of Chinese hamster ovary cells, by cDNA mutagenized to correspond to the NAGLU missense mutations, did not yield active enzyme, demonstrating the deleterious nature of the mutations. Nine of the 10 amino acid substitutions identified to date are clustered near the amino or the carboxyl end of alpha-N-acetylglucosaminidase, suggesting a role for these regions in the transport or function of the enzyme.

Acetylglucosaminidase↗
PubMed1998

Cerebral blood flow relationships associated with a difficult tone recognition task in trained normal volunteers.

Tone recognition is partially subserved by neural activity in the right frontal and primary auditory cortices. First we determined the brain areas associated with tone perception and recognition. This study then examined how regional cerebral blood flow (rCBF) in these and other brain regions correlates with the behavioral characteristics of a difficult tone recognition task. rCBF changes were assessed using H2(15)O positron emission tomography. Subtraction procedures were used to localize significant change regions and correlational analyses were applied to determine how response times (RT) predicted rCBF patterns. Twelve trained normal volunteers were studied in three conditions: REST, sensory motor control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral activation of primary auditory cortices, cerebellum and bilateral inferior frontal gyri. DEC-SMC produced significant clusters in the right middle and inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus and supplementary motor area; the left insula/claustrum; and the left cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a positive correlation in right inferior and middle frontal cortex; rCBF in bilateral auditory cortices and cerebellum exhibited significant negative correlations with RT These changes suggest that neural activity in the right frontal, superior temporal and cerebellar regions shifts back and forth in magnitude depending on whether tone recognition RT is relatively fast or slow, during a difficult, accurate assessment.

Acoustic Stimulation↗
PubMed1998

Combined solid-phase/solution synthesis of a 31-residue vasoactive intestinal peptide analog: general method for repetitive coupling of fragments without isolation and purification of intermediates.

A novel analog of vasoactive intestinal peptide (VIP) has been reported which exhibits high potency and enhanced duration of in vivo biological activity. This VIP analog, cyclo-(Lys21-Asp25)Ac[Glu8 Lys12 Nle17 Ala19, Asp25 Leu26,Lys27,28,Gly29,30,Thr31]-VIP, which also has a lactam bridge, has been reported to have relaxant effects that are significantly more potent than other beta-agonists such as salbutamol and salmeterol. Because it has potential use for the treatment of bronchial asthma in humans, various convergent syntheses were evaluated to enable the economic preparation of large quantities of this medium-sized hentriacontapeptide. From these studies we developed a combined solid-phase/solution synthesis which uses four protected fragments (each prepared by solid-phase synthesis with highly acid-labile resins) possessing Nalpha-9-fluorenylmethyloxycarbonyl and side-chain tert-butyl protection. Only equivalent amounts of each fragment were required to achieve near-quantitative coupling reactions using N-[(1H-benzotriazol-1-yl)(dimethylamino)methylene]-N-methylmeth anaminium hexafluorophosphate N-oxide/N-hydroxybenzotriazole. All reagents and side products were removed at each stage by simple extraction procedures. Final deprotection was carried out with 90% trifluoroacetic acid. Under these conditions only low levels of epimerization were observed (<2%). These diastereoisomers and other trace impurities were removed from the product in a single purification by preparative high-performance liquid chromatography. The procedure has been scaled up (10-g scale) and the final product obtained in an overall (nonoptimized) yield of 24%. This procedure for the repetitive coupling of fragments, without isolation of intermediates, may be generally applicable for the economic synthesis of other medium-sized and longer peptides.

Amino Acid Sequence↗
PubMed1998

Perspectives on genetic aspects of dental patterning.

Nearly a century of speculation and experimentation has gone into trying to understand the mechanisms that establish the pattern of the differentiated heterodont dentition. Regionally differing qualitative (combinatorial) expression of regulatory genes appears to be involved in this process. Work by our laboratory and others shows that the six members of the mammalian Dlx family of homeobox genes are expressed (a) at multiple times during dental development, (b) differently at different stages, (c) in a way that is related to their genomic organization as gene-pairs linked to three of the four Hox clusters of positional patterning genes. The expression appears to be involved in jaw regionalization, tooth initiation, and tooth development. However, this expression correlates with no single aspect of dental patterning or tooth development, involves redundant and complementary function, and developmental differences between the maxillary and mandibular dentition suggest that other elements remain to be identified. For example, the possibility that quantitative aspects of gene expression specify developmental fields in the dentition has not yet been investigated. Although the maxilla and mandible develop differently, indirect evidence suggests that, especially in the future midline (incisor) regions, both jaws may be patterned by a consistent process that occurs before neural crest migration takes place, and we hypothesize that signaling factors like Sonic hedgehog and Pax transcription factors may be involved.

Animals↗
PubMed1998

SCID/NCr mice naturally infected with Helicobacter hepaticus develop progressive hepatitis, proliferative typhlitis, and colitis.

Hepatitis, proliferative typhlitis, and colitis were characterized in young adult and older SCID/NCr mice naturally infected with Helicobacter hepaticus. Liver lesions consisted of Kupffer, Ito, and oval cell hyperplasia along with multifocal to coalescing coagulative hepatocyte necrosis. Numerous Warthin-Starry-positive bacteria were observed in the parenchyma, and there were minimal to mild accumulations of monocytic cells and neutrophils. Proliferative typhlitis was characterized by moderate to marked mucosal epithelial cell hyperplasia with mild monocytic and neutrophilic infiltration. Minimal to mild colitis with mucosal epithelial cell hyperplasia of the colon was most marked in older mice. Comparable gastrointestinal lesions were not observed in uninfected control SCID/NCr mice. H. hepaticus was cultured from fetal viscera of 2 of 11 pups sampled late in gestation from infected SCID/NCr females, suggesting transplacental infection of H. hepaticus. As expected, most of the naturally infected SCID/NCr mice had no serum immunoglobulin G response against H. hepaticus. These findings contrast with those in infected immunocompetent A/JCr mice, which develop a significant immune response to H. hepaticus associated with prominent multifocal mononuclear cell infiltrates in the liver, with only rare bacteria observable at the periphery of inflammatory foci or in the biliary canaliculi. The results demonstrate that chronic inflammatory and proliferative lesions simultaneously affecting the liver, cecum, and colon are associated with natural infection of SCID/NCr mice with H. hepaticus and that lesions are progressive with age. Concurrent infection with H. hepaticus may confound studies that have been attributed to similar lesions due to other experimental manipulations of SCID/NCr mice.

Animals↗
PubMed1998

Dynamic interactions and the evolutionary genetics of dental patterning.

The mammalian dentition is a segmental, or periodically arranged, organ system whose components are arrayed in specific number and in regionally differentiated locations along the linear axes of the jaws. This arrangement evolved from simpler dentitions comprised of many single-cusp teeth of relatively indeterminate number. The different types of mammalian teeth have subsequently evolved as largely independent units. The experimentally documented developmental autonomy of dental primordia shows that the basic dental pattern is established early in embryogenesis. An understanding of how genetic patterning processes may work must be consistent with the different modes of development, and partially independent evolution, of the upper and lower dentition in mammals. The periodic nature of the location, number, and morphological structure of teeth suggests that processes involving the quantitative interaction of diffusible signaling factors may be involved. Several extracellular signaling molecules and their interactions have been identified that may be responsible for locating teeth along the jaws and for the formation of the incisor field. Similarly, the wavelike expression of signaling factors within developing teeth suggests that dynamic interactions among those factors may be responsible for crown patterns. These factors seem to be similar among different tooth types, but the extent to which crown differences can be explained strictly in terms of variation in the parameters of interactions among the same genes, as opposed to tooth-type-specific combinatorial codes of gene expression, is not yet known. There is evidence that combinatorial expression of intracellular transcription factors, including homeobox gene families, may establish domains within the jaws in which different tooth types are able to develop. An evolutionary perspective can be important for our understanding of dental patterning and the designing of appropriate experimental approaches, but dental patterns also raise basic unresolved questions about the nature of the evolutionary assumptions made in developmental genetics.

Animals↗
PubMed1998

A cluster analysis of not-in-treatment drug users at risk for HIV infection.

The purpose of the analysis described here was to classify not-in-treatment drug users participating in the National Institute on Drug Abuse (NIDA)-sponsored Cooperative Agreement study into several "homogeneous" HIV risk groups using cluster analysis. Data for this analysis (N=17,778) were collected at 19 study sites in the United States and Puerto Rico. Measures selected for the cluster analysis were limited to (a) current drug use and HIV risk behaviors, (b) mutually exclusive behaviors, (c) behaviors directly related to HIV risk, and (d) behaviors that were not statistically rare. Eight homogeneous HIV risk clusters were produced. Crack cocaine use was the most distinguishing feature of three clusters. Another three clusters were distinguishable by drug injection and needle use practices. Two additional clusters could not be grouped with either the crack- or the injection-dominant clusters. Prostitution was the most distinguishing risk behavior of one of these clusters, and extremely high drug injection frequencies and relative rates of risky needle use characterized the other. Composition of the clusters varied significantly by gender, race/ethnicity, educational attainment, and drug use characteristics. In addition, perceptions and behaviors initiated to reduce the chances of becoming infected with HIV varied by cluster. Subjects in the crack-predominant clusters reported low perceptions of the chances of getting AIDS. Perceptions of the chances of becoming infected with HIV among subjects in the injection-predominant clusters were strongly related to injection frequency. Seroprevalence was also related to cluster. Higher rates of HIV infection were evident among the injection-predominant clusters, and higher rates were related to frequency of injection and the rate of risky needle use. Among the crack-predominant clusters, the relationship between drug use and sexual behaviors and HIV infection was less clear.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Lycopene uptake and tissue disposition in male and female rats.

Epidemiologic and clinical studies suggest that tomato consumption may reduce the risk of cancer. Lycopene, a hydrocarbon carotenoid, is the major carotenoid in tomatoes and, as a potent singlet oxygen quencher, has been considered by some to be the biologically active agent responsible for the reduction of cancer risk associated with tomato consumption. However, little is known concerning lycopene absorption or biological activity in rodent models of cancer. Therefore, the present study was designed to provide information regarding the uptake and tissue disposition of lycopene and related carotenoid after feeding a diet containing a carotenoid mixture extracted from tomatoes (Betatene). Betatene was added to the diet at 2.3, 0.9, 0.45, 0.23, 0.09 and 0 (mM/kg diet) and fed to male and female Fischer-344 rats for a period of 10 weeks. Using reverse phase HPLC methods, it was found that approximately 55% of administered lycopene was excreted in the feces. In both males and females, lycopene concentrations were highest in the liver (120-42 microg/g wet wt.); physiologically significant levels were detected in prostate (97-47 ng/g), lung (227-134 ng/g), mammary gland (309-174 ng/g) and serum (285-160 ng/ml). Tissue concentrations were related to dose with the exception of serum, and differences between males and females were minimal. Other carotenoids present in Betatene (i.e., phytoene, phytofluene, z-carotene and beta-carotene) were also absorbed and stored in the liver. These results indicate that lycopene, when incorporated into the semipurified AIN-76A diet, is absorbed in both male and female rats in a dose-related manner and can be detected at nanogram levels in a variety of target organs.

Animals↗
PubMed1998

[Effects of millimeter wave irradiation with different frequency and power density on their offsprings in mice].

OBJECTIVE: To determine the threshold of millimeter wave irradiation leading to fetal damage in mice and to clarify the mechanism of decrease in their learning and memory function. METHODS: Pregnant mice were irradiated by millimeter wave with frequencies of 37.4, 42.2, 53.0 and 60.0 GHz at power densities of 1 to 8 mW/cm2 for two hours daily from the 6th to 15th day of their gestation. Learning and memory functions of their offsprings were tested by a Y-type electric maze. M-cholinergic receptor (M-R), monoamine transmitter and arginine vasopressor (AVP) in the brain were determined for their offsprings by receptor radiation binding analysis (RBA), high performance liquid chromatography-electrochemical detection (HPLC-ECD) and radioimmunoassay (RIA). RESULTS: The minimal power density of millimeter wave of 37.4, 42.2, and 53.0, 60.0 GHz causing the decrease in learning and memory function, increase of Bmax in the hippocampus and decrease in dopamine (DA) in the brain of the adult offspring mice was five and three mW/cm2 and that causing the decrease in AVP in the hypothalamus was eight and five mW/cm2. Severity of damage in fetal offspring mice caused by irradiation increased with the power density of millimeter wave. Millimeter wave could not cause the increase of their body temperature in pregnant mice. CONCLUSION: Threshold of millimeter wave with frequencies of 37.4, 42.2 and 53.0, 60.0 GHz causing fetal damage in mice was three to five mW/cm2 and one to three mW/cm2, respectively. The decrease in learning and memory functions in offspring mice related with lowering of AVP and DA in the brain and of activity in cholinergic nerve. All these were caused by the non-thermal effects of millimeter wave without a frequency-specific pattern.

Animals↗