An electrochemical quartz crystal impedance study on the rising of an aqueous solution meniscus for a partially immersed gold electrode during the electrochemical reduction of oxygen

An electrochemical quartz crystal impedance system (EQCIS) was used to study the resonance behavior of an AT-cut 9-MHz piezoelectric quartz crystal (PQC) with its Au electrode partially immersed in KCl, Na2SO4 and NaClO4 aqueous solutions, respectively. An in situ determination of the immersed area and the height of the electrode was achieved by simultaneous measurements of the PQC electroacoustic admittance and the electrochemical impedance. The rising of the solution meniscus for a gold electrode partially immersed in aqueous solutions was found at oxygen reduction potentials and evaluated versus the electrolyte, electrolyte concentration, solution pH and oxygen concentration. The solution meniscus rising was explained based on a lowering of the contact-angle hysteresis and a continued collection of the water product at the solid-gas-solution interface during oxygen reduction.

Development of a thickness shear mode acoustic sensor based on an electrosynthesized molecularly imprinted polymer using an underivatized amino acid as the template

The preparation and characterization of electrosynthesized poly(o-phenylenediamine) (iPoPD) as a molecular imprinting material were studied by an in situ quartz crystal impedance method. The changes of delta f0, delta R1, delta L1 and delta C0 suggest that the polymer film was compact and rigid. The thickness shear mode (TSM) acoustic sensor modified with this material exhibits molecular recognition ability to the template molecule of DL-phenylalanine. In the range 2-20 mM, a linear relationship between the frequency shift delta f0 and logC was found from the calibration graph. Scatchard analysis of the relevant calibration graph offers information on the equilibrium of the binding interaction and the recognition sites. Using this electropolymerization technology, the preparation of the sensor was very simple and the reproducibility of preparation was very good. In particular, it offers possibilities for sensor miniaturization.

Studies on the expression of mRNA for anion transport related proteins in corneal endothelial cells

PURPOSE

Chloride and bicarbonate are necessary for maintenance of fluid transport by the corneal endothelium, however there is little information on the identity of anion transport proteins that could serve as anion efflux mechanisms in endothelial cells. Therefore, we ask whether mRNA for the anion transport related proteins, CFTR, CLC-2, ClC-3, ClC-5 and AE2, are expressed in human, bovine or rabbit corneal endothelium.

METHODS

RT-PCR was performed for CFTR, CLC-2, ClC-3, ClC-5 and AE2 using total RNA from fresh human, bovine and rabbit corneal endothelium as well as cultured bovine corneal endothelial cells (CBCEC). Specificity of PCR products was confirmed by sequencing.

RESULTS

RT-PCR analysis gave positive bands at the predicted size for CLC-3 and CLC-5 from fresh human, rabbit and bovine as well as CBCEC. However, for CLC-2, no band was apparent around the predicted size from fresh and cultured corneal endothelium. A band at the predicted size was obtained for CFTR from fresh human, rabbit and bovine endothelium, as well as from CBCEC. RT-PCR analysis for AE2 produced specific bands from fresh human, rabbit and bovine corneal endothelium, but no positive band was obtained from CBCEC. Sequencing analysis further confirmed the identities of CLC-3, CLC-5, CFTR and AE2 in corneal endothelium.

CONCLUSIONS

CFTR, CLC-3 and ClC-5 are expressed in fresh and cultured corneal endothelial cells. However, consistent with previous immunoblots studies, AE2 is only expressed in fresh corneal endothelium. These results have implications for modeling possible apical anion efflux mechanisms in corneal endothelium.

The effects of prenatal X-irradiation on hypoglossal nucleus: a GFAP immunohistochemical study

The effects of prenatal X-irradiation on hypoglossal (XII) nucleus were investigated in the rat. Pregnant animals were exposed to a single whole body X-irradiation on day 11 and 16 of gestation at a does of 1.3 Gy. The offspring were killed at 7-14 days of age for the histological and immunohistochemical observations. Nissl staining revealed no significant changes of XII motoneurons in these experimental animals. In the control case it was of interest that expression of glial fibrillary acidic protein-immunoreactivity (GFAP-IR) is largely confined to the dorsomedial region including the XII nucleus at the level caudal to the obex. Exposure of X-irradiation on day 16 of gestation led to similar expression of GFAP-IR in the nucleus at the same level. However, exposure on day 11 of gestation apparently led to strong expression of GFAP-IR in the XII nucleus at the level caudal to the obex and the expression was observed to extend rostrally. The GFAP-IR cells showed hypertrophy of cell bodies and longer cytoplasmic processes. Horse-radish peroxidase (HRP) injection into the tip of the tongue including the intrinsic muscles resulted in retrograde labeling in the ventromedial portion of the XII nucleus bilaterally from +0.30 to -1.25 mm. The present study would indicate that motoneurons of the XII nucleus supplying mainly the intrinsic and partly the extrinsic tongue muscles are more sensitive to X-ray exposure before the formation of the XII nucleus.

[Different flow augmentations in coronary, carotid and renal arteries with ECP in experimental canines]

Different flow augmentations were found in canine's coronary, carotid and renal arteries with ECP because of their different anatomical locations in aorta. We used the Electromagnetic Blood Flowmeters to measure the blood flow pre-ECP and during ECP. The results showed ECP increased the diastolic flow of coronary, carotid and renal arteries by 24.48% +/- 1.29%, 27.18% +/- 0.94% and 20.68% +/- 0.80% respectively, decreased their systolic flow by 4.77% +/- 0.48%, 6.45% +/- 0.99% and 9.60% +/- 0.70%, but augmented their mean flow by 18.24% +/- 2.01%, 19.38% +/- 1.47% and 8.42% +/- 0.94% respectively in experimental dogs. These data demonstrate that ECP can greatly increase the mean flow of coronary and carotid arteries but at the same time patently decrease the systolic flow of renal artery.

Arabidopsis NAC1 transduces auxin signal downstream of TIR1 to promote lateral root development

Auxin plays a key role in lateral root formation, but the signaling pathway for this process is poorly understood. We show here that NAC1, a new member of the NAC family, is induced by auxin and mediates auxin signaling to promote lateral root development. NAC1 is a transcription activator consisting of an N-terminal conserved NAC-domain that binds to DNA and a C-terminal activation domain. This factor activates the expression of two downstream auxin-responsive genes, DBP and AIR3. Transgenic plants expressing sense or antisense NAC1 cDNA show an increase or reduction of lateral roots, respectively. Finally, TIR1-induced lateral root development is blocked by expression of antisense NAC1 cDNA, and NAC1 overexpression can restore lateral root formation in the auxin-response mutant tir1, indicating that NAC1 acts downstream of TIR1.

[Raman spectra of the serums from cancerous persons]

The serums of different categories, those who are normal people and those who are patient suffering from nasopharyngeal cancer, liver cancer and chronic leukaemia, were determined by laser Raman spectra at the range of 0-2,000 cm-1. The results demonstrated that the serums of those who are suffering from the same disease show different characteristic peak height, but their Raman spectrogram characteristics are almost the same. There exists great difference in the laser Raman spectrogram for the serums of the different kinds of cancerous patients. Near the characteristic peaks of laser Raman spectrograms of serums from the cancerous patients, the normal person's serum has no Raman spectrogram characteristic peak.

[Preparation and identification of hammerhead ribozyme in vitro against rat caspase-3 mRNA fragment]

OBJECTIVE

To study the transcript effect and cleavage activity in vitro of rat Caspase-3 specific ribozyme (Rz107 and Rz544).

METHODS

Rat caspase-3 gene fragment was cloned into T-vector under the control of T7 promoter. (32)P-labeled caspase-3 transcript was target-RNA. Rz107 and Rz544 genes against caspase-3 mRNA were cloned and transcribed in vitro. Cleavage reaction was detected.

RESULTS

It was found that Rz107 was active at 37 degrees C and more so at higher temperature within allowing temperature range. The optimal temperature was 50 degrees C. For Rz107, Km and kcat was 14.13 nmol/L and 2.31 min(-1), respectively. However, the Rz544 had no cleavage activity at all.

CONCLUSION

Rz107 prepared in vitro possesses the perfect specific catalytic cleavage activity. It is hopeful that Rz107 would be developed to be a new nucleic acid drug that could effectively inhibit the inflammation of hepatitis through cleaving the key gene, caspase-3, in apoptosis in vivo.

Induction of mouse CYP2J by pyrazole in the eye, kidney, liver, lung, olfactory mucosa, and small intestine, but not in the heart

We have recently shown that rat CYP2J4 is inducible by pyrazole in liver, small intestine, and olfactory mucosa. The aim of the present study was to determine whether mouse CYP2Js are also inducible by pyrazole, which was known to induce CYP2A5 in mouse liver and kidney, but not in lung or olfactory mucosa. CYP2J proteins were detected in mouse liver, lung, kidney, heart, eye, olfactory mucosa, and small intestine by immunoblot analysis with an anti-CYP2J4 antibody. The microsomal level of the CYP2J4-related P450s in various mouse tissues ranked in the order of small intestine > olfactory mucosa > liver > kidney > or = heart > lung > eye. Induction of the CYP2J proteins was observed in the eye, liver, lung, kidney, olfactory mucosa, and small intestine, but not in the heart, after daily i.p. injection of pyrazole at 120 or 200 mg/kg for 3 days. CYP2J proteins were induced similarly in C57BL/6 and DBA/2 mice. CYP2A5 was detected in the small intestine in addition to liver and olfactory mucosa; however, treatment with pyrazole induced CYP2A5 in the liver, but not in the olfactory mucosa or the small intestine. Induction of CYP2J mRNAs was also observed by RNA blot analysis with a CYP2J4 cDNA probe. RNA-polymerase chain reaction analysis showed that, in both untreated and pyrazole-treated mice, CYP2J5 was expressed in the kidney and liver, but not in the other tissues examined, whereas CYP2J6 was detected in all tissues examined. The different tissue selectivities in CYP2A5 and CYP2J induction by pyrazole suggest involvement of different regulatory mechanisms.

Expression and localization of Na(+)-HCO(3)(-) cotransporter in bovine corneal endothelium

Functional studies support the presence of the Na(+)-HCO(3)(-) cotransporter (NBC) in corneal endothelium and possibly corneal epithelium; however, molecular identification and membrane localization have not been reported. To test whether NBC is expressed in bovine cornea, Western blotting was performed, which showed a single band at approximately 130 kDa for freshly isolated and cultured endothelial cells, but no band for epithelium. Two isoforms of NBC have recently been cloned in kidney (kNBC) and pancreas (pNBC). RT-PCR was run using cultured and fresh bovine corneal endothelial and fresh corneal epithelial total RNA and specific primers for kNBC and pNBC. RT-PCR analysis for pNBC was positive in endothelium and weak in epithelium. The RT-PCR product was subcloned and confirmed as pNBC by sequencing. No specific bands for kNBC were obtained from corneal cells. Indirect immunofluorescence and confocal microscopy indicated that NBC locates predominantly to the basolateral membrane in corneal endothelial cells. Furthermore, Na(+)-dependent HCO(3)(-) fluxes and HCO(3)(-)-dependent cotransport with Na(+) were elicited only from the basolateral side of corneal endothelial cells. Therefore, we conclude that pNBC is present in the basolateral membrane of both fresh and cultured bovine corneal endothelium and weakly expressed in the corneal epithelium.

[Effect of qiongyugao on the action of DDP in inhibiting the division of GLC-82 cell strain in vitro]

OBJECTIVE

To observe the effect of Qiongyugao (QYG) on the action of DDP in inhibiting the division of GLC-82 cell strain in vitro.

METHODS

The method of serum pharmacology was used in observing the morphological change of the cancer cells. By accounting the number of the live cells of each day during 6 days respectively, the growth curve was drawn up. The effects of the three groups on the cancer cells apoptosis of GLC-82 cell strain were analysed by FACS. RESULLTS: The growth of the cancer cells in control group (normal saline) was much better than the other two groups; in chemical therapy group (DDP), the number of the live cells almost kept steady; the number of the live cells in combined group(DDP plus QYG) became even lower. QYG could enhance the action of DDP in inducing the apoptosis of GLC-82 cells strain remarkably.

CONCLUSION

QYG can enhance the effects of chemotherapy in inhibiting cancer cells division and inducing their apoptosis.

Effect of tissue non-specific alkaline phosphatase in maintenance of structure of murine colon and stomach

The gastrointestinal tract of mammals secretes a phospholipid-rich membrane that is enriched in alkaline phosphatase (AP) and surfactant proteins (surfactant-like particle, SLP). The production of this particle is stimulated in the small intestine by fat feeding and in cultured cells in vitro by transfection with intestinal alkaline phosphatase (IAP). To test whether tissue non-specific alkaline phosphatase (TNAP) was a factor in stimulating surfactant-like particle production in stomach and colon (tissues expressing TNAP), mice lacking this enzyme were studied. Mice were harvested at 8 days of life, when body weight of homozygous animals (TNAP -/-) was about half that of congenic controls (TNAP +/+) or heterozygotes (TNAP +/-), but before seizures had begun. No difference in content of the major SLP protein (65 kDa) by Western blotting or immunocytochemistry was seen in stomach or colon of TNAP -/- vs. TNAP +/+ animals, but the content was only about half in the IAP-expressing small bowel. Transmission electron microscopy of the TNAP -/- small bowel showed large dilated lysosomes and residual bodies. Colonocytes and gastric surface epithelial cells from the same animals showed mitochondria containing homogeneous dense inclusions, consistent with neutral lipid. In the underweight homozygous animals, there was a decrease in the neuronal content of submucosal ganglia in the jejunum and ileum and of myenteric ganglia in the jejunum of TNAP -/- animals. These findings suggest that (1) TNAP is not important in maintaining surfactant-like particle content of tissues that express TNAP, (2) normal fat absorption is important in maintaining SLP content in the small intestine, and (3) TNAP is important in the maintenance of some intestinal structures, and perhaps their function.

Detection and analysis of Bacillus subtilis growth with piezoelectric quartz crystal impedance based on starch hydrolysis

A piezoelectric quartz crystal (PQC) impedance method based on the alpha-amylase-catalyzed hydrolysis of starch present in a culture medium has been developed for in situ monitoring of the whole growth process of Bacillus subtilis and the variation in the activity of alpha-amylase during bacterial growth. An S-shaped response behavior was observed for Deltaf(0), and simultaneously inverse S-shaped responses were found for DeltaR(1) and DeltaL(1). The ratio of DeltaR(1) to Deltaf(0) or DeltaL(1) coincided well with that calculated from Martin's equations reflecting the solution density-viscosity effect, suggesting that the continuing change in liquid loading onto the PQC surface causes significant variation in Deltaf(0), DeltaR(1), and DeltaL(1). Bacterial growth equations were derived from the kinetics of the enzyme-catalyzed hydrolysis of starch, which fit well with the experimental responses of Deltaf(0), DeltaR(1), and DeltaL(1). Kinetic parameters of bacterial growth, including the asymptote (A), the maximum specific growth rate (microm), and the lag time (lambda), were obtained and were in good agreement with those obtained from the pour plate count method. The variation in the activity of alpha-amylase exhibited peak-type behavior with its maximum value at the later stage of the log phase. In addition, the influence of initial bacterial concentration was also investigated.

Study of the Adsorption of Glutathione on a Gold Electrode by Using Electrochemical Quartz Crystal Impedance, Electrochemical Impedance Spectroscopy, and Cyclic Voltammetry

Adsorption of a biological peptide, glutathione, on a gold electrode was studied by using electrochemical quartz crystal impedance (EQCI), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) techniques. The time courses of responses of piezoelectric and electrochemical impedance parameters were simultaneously obtained during the adsorption processes of the two forms of peptide, oxidized and reduced glutathione. It was found that the frequency curve due to the oxidized glutathione (GSSG) adsorption exhibited a character of a sum of two exponential functions. For reduced glutathione (GSH), the frequency adsorption curve could be expressed by a first-order reaction kinetic model and the corresponding kinetic parameters at different amounts of GSH were obtained. The heterogeneous charge-transfer rate constants of ferricyanide/ferrocyanide before and after the peptide adsorption were determined by CV and EIS methods, respectively. According to the simple equivalent electric network of the electrochemical interface, the electrochemical impedance parameters were also obtained. The results showed that the proposed method should be found in wider applications in interfacial biochemistry studies since these combined techniques have advantages in real time multidimensional information including electrochemical and electrochemical impedance parameters. Copyright 2000 Academic Press.

Polymorphism of human platelet alloantigen in Chinese patients with acute myocardial infarction and acute ischemic stroke

OBJECTIVE

To investigate the gene frequencies of 5 major human platelet alloantiqens (HPA 1-5) in Chinese population and to assess if polymorphism of HPA was associated with Chinese acute myocardial infarction (AMI) and acute ischemic stroke (AIS).

METHODS

HPA 1-5 genotyping was performed by PCR using allele specific primers and restriction enzyme digestion based on PCR products in 95 AMI cases, 188 AIS cases and 270 normal controls. Gene frequency distribution was tested by Hardy-Weinberg equilibrium and comparison of HPA gene frequencies between the patient and control groups by chi 2 test.

RESULTS

The gene frequencies of HPA 1-5 were the followings: HPA1a: 91%; 1b: 9%; HPA 2a: 94%; 2b: 6%; HPA 3a: 83%; 3b: 17%; HPA 4a: 98%; 4b: 2%; HPA5a: 97%; 5b: 3%. We found there were no significant differences in HPA 1-5 gene frequencies between AMI patients and normal controls. In AIS patients group HPA-2a allele frequency was significant higher than in controls, but this allele gene frequency in two groups (0.94 and 0.99) was very close and too many subjects in these two groups were overlapped. Otherwise no differences was found in other 4 HPA systems between cases and controls.

CONCLUSION

Polymorphism of HPA were not inherited risky factors and not associated with chinese arterial thrombotic diseases such as AMI and AIS.

The two isozymes of rat intestinal alkaline phosphatase are products of two distinct genes

Rat intestinal alkaline phosphatases (IAP-I and -II) differ in primary structure, substrate specificity, tissue localization, and response to fat feeding. This study identifies two distinct genes ( approximately 5-6 kb) corresponding to each isozyme and containing 11 exons of nearly identical size. The exon-intron junctions are identical with those found in IAP genes from other species. The 1.7 and 1.2 bp of 5' flanking regions isolated from each gene, respectively, contain Sp1 and gut-enriched Kruppel-like factor (GKLF) binding sites, but otherwise show little identity. There is a potential CAAT-box 14 bp 5' to the transcriptional start site, 36 bp upstream from IAP-I, and a TATA-box 31 bp 5' to the transcriptional start site, 55 bp upstream from IAP-II. Transfection of these promoter regions (linked to luciferase as a reporter gene) into a kidney cell line, COS-7, produced the differential response to oleic acid expected from in vivo studies, i.e., threefold increase using the 5' flanking region of IAP-II, but not IAP-I. This response was not reproduced by 5,8,11,14-eicosatetraynoic acid (ETYA) or clofibrate, suggesting that peroxisome proliferator response elements are not involved. Isolation of the IAP-II gene will allow determination of the sequences responsible for dietary fat response in the enterocyte.

[The correlation between anticardiolipin antibodies and disease activity in patients with systemic lupus erythematosus]

This study was conducted to determine the prevalence and clinical association of anticardiolipin antibodies (ACA) in serum of patients with systemic lupus erythematosus (SLE). ACA (IgG, IgA, IgM) was measured by enzyme-linked immunosorbent assay (ELISA) in the serum sample of 87 patients of SLE. The prevalence rates of ACAIgG, ACAIgA and ACAIgM were 62.1%, 52.9% and 35.6% respectively. The titers of ACAIgG and ACAIgM were positively correlated with the disease activity (r = 0.2763, P = 0.044; r = 0.3294, P = 0.018); ACAIgG, ACAIgA and ACAIgM were negatively correlated with complement C3 (r = -0.4737, P = 0.000; r = -0.2990, P = 0.017; r = -0.2758, P = 0.029); and ACAIgG was negatively correlated with complement C4 (r = -0.4079, P = 0.005). The titers of ACAIgA in patients with thrombosis was higher than that in patients without thrombosis. The patients with central nervous system involvement (CNS-SLE) had significantly higher ACAIgG and ACAIgM titers, compared with those without CNS-SLE. The results indicate there is a correlation between ACA titers and disease activity. In patients with thrombosis, the titer of ACAIgA is higher, and in patients with CNS-SLE, the titers of ACAIgG and ACAIgM are higher.

[Detection of microbes adherent to particles in a closed environment]

OBJECTIVE

In order to provide reference for controlling and monitoring the environmental contamination in the spacecraft, the species and amount of microbes, which adhere to the suspended particles with different size in a closed environment were detected.

METHOD

According to USA EPA IP-10, particles were continuously sampled by an impactor in a closed environment. The particles were divided into three grades by their aerodynamic diameters (AD): 100 micrometers > or = AD > 10 micrometers, 10 micrometers > or = AD>2 micrometers and AD < or = 2 micrometers. Clean outdoor air was collected as control by the same way. The collected particles were precisely weighed. The microbes that adhere to the particles were cultivated, counted and identified.

RESULT

By calculating total suspended particles (TSP) and inhalant particles (IP) of the closed environment, counting, clarifying and identifying the microbes, 6 kinds of bacteria, 2 genus of actinomyces and 6 kinds of fungi that adhere to the particles were detected.

CONCLUSION

The particles in a closed environment may have some effect on human health and instruments.

[Endothelial dysfunction and injury of placental and umbilical vessels in pregnancy-induced hypertension is associated with tumor necrosis factor]

OBJECTIVE

To investigate the relation between endothelial dysfunction and injury of placental and umbilical vessels in pregnancy-induced hypertension (PIH) and tumor necrosis factor (TNF).

METHODS

The concentration of plasma TNF, endothelin (ET) and nitric oxide (NO) in PIH women and normal pregnant women (control group) were measured. The ultrastructure of placenta and umbilical vein endothelial cells in PIH and normal pregnant women was observed. The ultrastructure of endothelial cells in culture with TNF (400 u/ml) was also observed.

RESULTS

Maternal plasma TNF and ET levels in PIH patients were (2.27 +/- 0.42) micrograms/L and (73.31 +/- 9.98) ng/L, respectively, higher than that in the control [TNF and ET lever were (1.72 +/- 0.25) micrograms/L and (2.32 +/- 10.44) ng/L, respectively]. NO level in PIH patients was (104.93 +/- 20.54) mumol/L, lower than that in the control [NO lever was (138.25 +/- 22.16) mumol/L] (P < 0.05). The ultrastructure of placental and umbilical vascular endothelial cells in moderate and severe PIH patients revealed injured. Similar injury was observed in endothelial cells in culture with TNF.

CONCLUSIONS

TNF can induce the endothelial cells dysfunction and injury. It may be involved the pathogenesis of PIH.

[Polymorphism of human platelets alloantigens in Chinese patients with acute myocardial infarction and acute ischemic stroke]

OBJECTIVE

To investigate the gene frequencies of 5 major human platelets alloantigens (HPA 1 - 5) in Chinese population and to assess if polymorphism of HPA is associated with acute myocardial infarction (AMI) and acute ischemic stroke (AIS) in the Chinese.

METHODS

HPA 1 - 5 genotyping was performed with PCR using allele specific primers and restriction enzyme digestion based on PCR products in 95 AMI patients, 188 AIS patients and 270 normal controls. Gene frequency distribution was tested by Hardy-Weinberg equilibrium. Comparisons of HPA gene frequencies between the patient and control groups were made by chi(2) test.

RESULTS

The gene frequencies of HPA 1 - 5 were listed as follows: HPA1a, 91%; HPA 1b, 9%; HPA 2a, 94%; HPA 2b, 6%; HPA 3a, 83%; HPA 3b, 17%; HPA 4a, 98%; HPA 4b, 2%; HPA 5a, 97%; HPA 5b, 3%. No significant differences were found in HPA 1 - 5 gene frequencies between AMI patients and normal controls. In AIS patient group, HPA-2a allele frequency was significantly higher than that in controls, but this allele gene frequency in the two groups was very close (0.99 and 0.94, respectively) and too many subjects in the two groups were overlapped. No differences were found in the other 4 HPA systems between patients and controls.

CONCLUSION

Polymorphism of HPA is not an inherited risk factor and is not associated with Chinese arterial thrombotic diseases, such as AMI and AIS.

Prenatal X-irradiation increases GFAP- and calbindin D28k-immunoreactivity in the medial subdivision of the nucleus of solitary tract in the rat

Glial fibrillary acidic protein- (GFAP) and calbindin D28k-immunoreactivity (IR) were investigated in the medial subdivision of the nucleus of the solitary tract (mNST) of prenatally X-irradiated rats. Pregnant rats were exposed to a single whole-body X-irradiation on day 11 or 16 of gestation at a dose of 1. 3 Gy. The offspring were killed at 7-14 days of age for the immunohistochemical observations. Rat pups showed strong GFAP-IR at the level rostral to the obex when receiving X-rays on day 11 of gestation, with hypertrophy of astrocyte cell bodies and cytoplasmic processes, but weak GFAP-IR when receiving X-rays on day 16 of gestation. Calbindin D28k-IR was stronger in the animals receiving X-rays on day 11 or 16 of gestation compared to that in the control animals. In the present study, the increase of GFAP- and calbindin D28k-IR cells in the mNST might indicate that adaptative mechanisms are taking place to preserve integrated nervous system function and possibly, to provide neuroprotection.

[Role of tumor necrosis factor -alpha in the pathogenesis of pregnancy-induced hypertension]

OBJECTIVE

To investigate the role of tumor necrosis factor-alpha (TNFalpha) in the pathogenesis of pregnancy induced hypertension (PIH) by damaging endothelial cells.

METHODS

41 patients with PIH and 17 healthy pregnant women were studied. The concentration of TNFalpha in maternal plasma was measured by sensitive radioimmunoassay. The morphology of endothelial cells of placental blood vessels was observed. Endothelial cells were incubated in the presence of TNFalpha (400 U/ml) and sera (30% vol/vol) from PIH women and normal pregnant women to observe their growth and shape.

RESULTS

Maternal plasma TNFalpha level in PIH was 2.29 microgram/L +/- 0.51 microgram/L, higher than that in normal pregnancy (the latter was 1.73 microgram/L +/- 0.25 microgram/L, t = 5.60, P < 0.01). The endothelial cells of placental blood vessels in PIH revealed morphologic damages. Both sera of PIH women and TNFalpha were cytotoxic to endothelial cells in culture, including inhibition of the proliferation and morphologic changes of the cells.

CONCLUSION

Damage of the endothelial cells of placental blood vessels is associated with the abnormal increase in the maternal blood TNFalpha. Sera of PIH women can damage the endothelial cells in culture and this effect is also associated with TNFalpha.

Selective impairment of corticotropin-releasing factor1 (CRF1) receptor-mediated function using CRF coupled to saporin

CRF is the main component in the brain neuropeptide effector system responsible for the behavioral, endocrine, and physiological activation that accompanies stress activation. Reduced CRF system activation plays a role in the etiology of a variety of psychiatric and metabolic disease states. We have developed a novel protein conjugate that joins native rat/human CRF to a ribosome-inactivating protein, saporin (CRF-SAP), for the purpose of targeted inactivation of CRF receptor-expressing cells. Cytotoxicity measurements revealed that CRF-SAP (1-100 nM) produced concentration-dependent and progressive cell death over time in CRF1 receptor-transfected L cells, but at similar concentrations had no effect on CRF2alpha receptor-transfected cells. The CRF-SAP-induced toxicity in CRF1-transfected cells was prevented by coincubation with the competitive CRF1/CRF2 receptor peptide antagonist, [D-Phe12]CRF-(12-41), or the selective nonpeptide CRF1 receptor antagonist, NBI 27914. Finally, in cultured rat pituitary cells that express native CRF1 receptors, CRF-SAP suppressed CRF-induced (1 nM) ACTH release. GnRH (1-10 nM) stimulated LH release was also assessed in the same pituitary cultures. Although there was a slight decrease in LH release from these cultures, this decrease was observed with CRF-SAP or SAP alone, suggesting that the response was nonspecific. Taken together, these results suggest the utility of CRF-SAP as a specific and subtype-selective tool for long term impairment of CRF1 receptor-expressing cells.

Cardiac afferents to the nucleus of the tractus solitarius: A WGA-HRP study in the rat

Central distribution of the sensory fibers of the heart was investigated in the rat by the use of transganglionic transport of horseradish peroxidase (HRP). After the left intercostal thoracotomy was done under deep anesthesia and artificial respiration, wheat germ agglutinin-conjugated HRP (WGA-HRP) was injected into the left and right ventricular walls and the apex of the heart. HRP-labeled fibers were observed to be distributed to the dorsomedial portion of the medulla oblongata through the vagal nerve. The labeled fibers were present in various subnuclei of the nucleus of the tractus solitarius (NTS) bilaterally at the level of +0.36 to -1.74 mm to the obex. However, the most conspicuous feature in the present study was that the labeled fibers were exclusively confined to the medial, ventrolateral and commissural NTS with some distribution to the dorsolateral NTS. Although the labeling in the medial and ventrolateral NTS was observed to extend rostrocaudally, it was of interest that the labeling in the medial NTS was divided into the ventral and dorsal parts at the level around the obex. Accumulation of the labeled fibers in the commissural NTS was found at the level caudal to the obex and these fibers were traced to the caudal portion of its subnucleus with a gradual decrease in number. This pattern of distribution of cardiac afferents in the NTS was considered to be peculiar to the rat, because it was quite different from that reported previously in the cat.

The study on the expression of membrane HSP70 protein in H22 cell and its immunoprotective mechanism against carcinoma

The mRNA and protein expression of HSP70 were studied using RT-PCR and FCM techniques. It's immune protective effects in vivo and the cytotoxicity in vitro were also observed. Results showed that cell viability didn't change under 42-43 degrees C, but declined in 44-45 degrees C; the level of HSP70 mRNA decreased initially (0.5-4.0 hour) but gradually resumed and increased from 8 to 12 hours at 42 degrees C. The positive cells expressed membrane HSP70 were significantly higher in heat shocked group than in a control group (P<0.001); the highest positive rate was 96.8% at 43 degrees C. The C3H mice immunized with heat shocked H22 cells could resist a secondary subcutaneous inoculation of parental H22 cells and their tumorigenic rate was significantly lower than that in mice immunized with parental H22 cells and RPMI 1640 control mice, which were 1/9.7/8 and 8/8, respectively. Their median survival time was also longer than that of parental cell group and RPMI 1640 control group, which were >90 days, 73.5 days, and 39.5 days, respectively. Through heat-treated tumor cell and lymphocyte mixed culture (TLMC), the induced lymphocytes had higher cytotoxic activities than that of splenic cells. The cytotoxicity against H22 cells reached 65.38% (2 hrs, 42 degrees C) and 67.84% (12 hrs, 43 degrees C) and could be blocked by anti-HSP70 McAb. Phenotype analysis revealed that the rate of TCR gammadelta+ cells rose with increasing cytotoxic activity, but no similar changes could be found in the CD4+ CD8+ TCR alphabeta+ subset. These results suggest that proper heat shock conditions can improve the immunogenicity of tumor cells and CD4- CD8- TCR gammadelta+ T carried on cytotoxic function via the HSP70 molecule.

Effect of short-term ethanol exposure on the suprachiasmatic nucleus of hypothalamus: immunohystochemical study in mice

Morphological changes of the suprachiasmatic nucleus (SCN) of the hypothalamus were investigated in mice exhibiting intoxication signs of stages 2 or 3 after a short application term of 6% ethanol. Alterations in glial cells and neurons were examined using anti-glial fibrillary acidic protein (GFAP) and anti-calbindin D28k monoclonal antibody, respectively. The results revealed that short-term ethanol exposure led to strong expression of GFAP-immunoreactivity (GFAP-IR) in the dorsomedial part of the SCN. Furthermore, GFAP-IR astrocytes showed an increase in number and hypertrophy with longer processes. However, calbindin D28k-IR neurons were apparently little changed in the SCN. It is concluded that neuroadaptive response of astrocytes could occur before the neurotoxic effects emerge on neurons on the SCN.

F4/80-positive cells rapidly accumulate around tubuli recti and rete testis between 3 and 4 weeks of age in the mouse: an immunohistochemical study

PROBLEM

Previous studies demonstrated that F4/80 antigen (murine macrophage-specific antigen)-positive cells in testes of normal adult mice accumulate particularly in the interstitium adjacent to the tubuli recti and rete testis (i.e., the central region). However, it remains unknown whether this accumulation is a congenital or acquired phenomenon.

METHOD OF STUDY

The distribution of F4/80-positive cells on frozen sections of testes obtained from various aged mice was immunohistochemically examined to determine when the positive cells specifically accumulate in the central region.

RESULTS

F4/80-positive cells were homogeneously distributed throughout the testicular interstitium with no specific accumulation until 2 weeks of age. However, at 3 weeks of age, the density of positive cells in the central region became slightly, but significantly, higher than that in the interstitium between the seminiferous tubules. Between 3 and 4 weeks of age, the cell density in the central region increased rapidly, the density at 4 weeks of age reaching the level of the mature testes of 8-week-old mice.

CONCLUSION

These results demonstrate that the specific accumulation of F4/80-positive cells in the central region is an acquired phenomenon, which starts and ends before puberty.

Interleukin-4 weakens host resistance to pulmonary and disseminated cryptococcal infection caused by combined treatment with interferon-gamma-inducing cytokines

We examined the role of interleukin (IL)-4 in host resistance against infection with Cryptococcus neoformans. First, we examined the effects of a neutralizing anti-IL-4 monoclonal antibody (mAb) on survival of mice infected intratracheally with this fungal pathogen. We also compared the number of live C. neoformans in lungs and brains of treated and untreated mice. Treatment with anti-IL-4 mAb significantly prolonged survival of infected mice and reduced the lung and brain burdens of C. neoformans, which was associated with increased production of IFN-gamma in lungs. In the next experiments, infected mice were treated with two IFN-gamma-inducing cytokines, IL-12 and IL-18, known to enhance protection against infection. We then evaluated the effect of such treatment on the number of live microorganisms and concentration of IL-4 in lungs. These two parameters showed a statistically significant relationship, suggesting a negative regulation of host protection by IL-4. Finally, we examined the effects of IL-4 treatment and administration of neutralizing anti-IL-4 mAbs on host protection against C. neoformans and local production of IFN-gamma in lungs induced by treatment with IL-12/IL-18. The former treatment suppressed host protection and reduced IFN-gamma production, while the latter produced the opposite effects. Our results indicated that IL-4 suppressed the host defense mechanisms against infection with C. neoformans potentiated by IFN-gamma-inducing cytokines probably through the suppression of local production of IFN-gamma.

Major differences between the testis and epididymis in the induction of granulomas in response to extravasated germ cells. I. A light microscopical study in mice

A spermatic granuloma is a chronic inflammatory lesion which surrounds extravasated spermatozoa. Clinically, the lesion develops in the interstitial spaces of the epididymis and vas deferens, and only exceptionally in the testis itself. In the present study, murine testes and epididymides were injured using a needle and the histological appearances of these organs was then compared. Traumatic injury induced extravasation of germ cells in both testes and epididymides. A few days later, spermatic granulomas consistently formed in the epididymides, however, such lesions were not induced in the testes. To examine the possibility that epididymal spermatozoa have inherently greater ability to form spermatic granulomas than do testicular germ cells, isolated epididymal spermatozoa or testicular germ cells were locally injected into the testes and epididymides of recipient mice. Spermatic granulomas readily formed in the epididymides after local injection of either epididymal spermatozoa or testicular germ cells. In contrast, such lesions did not form in the testes even when epididymal spermatozoa were injected. Therefore, this study suggests that the microenvironment of the testicular interstitium, rather than the extravasated components from the ruptured seminiferous tubules, is the main factor determining the limited formation of spermatic granulomas in the testis.

Chemokine responses and accumulation of inflammatory cells in the lungs of mice infected with highly virulent Cryptococcus neoformans: effects of interleukin-12

We examined the mechanisms involved in the development of lung lesions after infection with Cryptococcus neoformans by comparing the histopathological findings and chemokine responses in the lungs of mice infected with C. neoformans and assessed the effect of interleukin (IL) 12 which protects mice from lethal infection. In mice infected intratracheally with a highly virulent strain of C. neoformans, the yeast cells multiplied quickly in the alveolar spaces but only a poor cellular inflammatory response was observed throughout the course of infection. Very little or no production of chemokines, including MCP-1, RANTES, MIP-1alpha, MIP-1beta and IP-10, was detected at the mRNA level using RT-PCR as well as at a protein level in MCP-1, RANTES and MIP-1alpha. In contrast, intraperitoneal administration of IL-12 induced the synthesis of these chemokines and a marked cellular inflammatory response involving histiocytes and lymphocytes in infected mice. Our findings were confirmed by flow cytometry of intraparenchymal leukocytes obtained from lung homogenates which showed IL-12-induced accumulation of inflammatory cells consisting mostly of macrophages and CD4+ alphabeta T cells. On the other hand, C-X-C chemokines including MIP-2 and KC, which attract neutrophils, were produced in infected and PBS-treated mice but treatment with IL-12 showed a marginal effect on their level, and neutrophil accumulation was similar in PBS- and IL-12-treated mice infected with C. neoforman. Our results demonstrate a close correlation between chemokine levels and development of lung lesions, and suggest that the induction of chemokine synthesis may be one of the mechanisms of IL-12-induced protection against cryptococcal infection.

The cloning of plant E2F, a retinoblastoma-binding protein, reveals unique and conserved features with animal G(1)/S regulators

Association of the retinoblastoma (Rb) protein with E2F transcription factors is central to cell cycle-specific gene expression and growth in animal cells. Whether Rb-E2F complexes are also involved in plant cell growth and differentiation is still unknown since E2F proteins have not yet been identified in plants. Here we report the isolation and characterisation of a wheat E2F (TmE2F) cDNA clone. Interestingly, the overall domain organisation of plant E2F is related to the human E2F-1/2/3 subset but its primary sequence is slightly more related to the E2F-4/5 subset. TmE2F-Rb binding depends on residues, located at the C-terminus, which are different from those of animal E2Fs. However, the acidic or hydrophobic nature of certain residues is maintained, strongly suggesting that they may have a crucial role in E2F activities. Plant E2F is expressed in proliferating cultured cells and in differentiated tissues and is up-regulated early in S phase. Our studies reinforce the idea that G(1)/S regulators in plants are unrelated to those of yeast cells but similar to those of animal cells and provide new tools to analyse the links between cell cycle regulators, plant growth and developmental signals.

Surgical treatment of patent ductus arteriosus (PDA) through mini subaxillary extrapleural approach

In this study, a new surgical technique for the surgical treatment of patent ductus arteriosus (PDA) is evaluated. The subaxillary extrapleural approach was performed on 836 patients with patent ductus arteriosus. And 20 of these patients were evaluated for postoperative outcomes compared with the routine technique. The results indicated that the new method is safe, less traumatic and has better cosmetic effects. It is concluded in this article that the subaxillary extrapleural approach for PDA is a good modification to the routine surgical technique, that is surgery through the posterolateral approach.

Association of edentulousness with systemic factors in elderly people living at home

OBJECTIVE

To examine the association of edentulousness with systemic factors: age, gender, tobacco-smoking, alcohol intake, body mass index, functioning in daily living, cortical thickness at the mandibular angle, and systemic diseases: bone-fracture (an indicator for osteoporosis), diabetes, thyroid disease, hyperparathyroidism, asthma, heart failure, hypertension.

METHODS

The study population comprised 293 elderly subjects, 124 (42%) edentulous and 169 (58%) dentate. The data from clinical and radiographic examinations and structured interviews were analyzed by multiple logistic regression.

RESULTS

When edentulousness in both the mandible and the maxilla was considered, history of bone fracture and tobacco-smoking were significantly related to complete edentulousness with odds ratios (OR) of 2.51 (95% CI: 1.47-4.28) and 2.42 (95% CI: 1.32-4.43) respectively, associations independent of age and gender. A similar association was found for the edentulous mandible. In the elderly subjects with an edentulous maxilla, besides the significant factors of history of bone fracture and tobacco-smoking, asthma was also associated with edentulousness at an odds ratio of 10.81 (95% CI: 1.38-84.66), oldest subjects most often being edentulous (OR: 2.23, 95% CI: 1.13-4.39). Diabetes was not related to edentulousness either in the mandible or in the maxilla.

CONCLUSIONS

The finding of associations of history of bone fracture, tobacco-smoking, and asthma with edentulousness emphasizes the association of systemic conditions with edentulousness. Advanced age was related to an edentulous maxilla. The relationship between asthma and total tooth loss in the maxilla might suggest a local oral effect of medications used by asthmatic patients.

A monoclonal antibody to ICP4 of MDV recognizing ICP4 of serotype 1 and 3 MDV strains

Monoclonal antibodies (MAbs) were prepared against ICP4 of Marek's disease virus (MDV). Mice were inoculated with ICP4 obtained from High-Five insect cells infected with a recombinant baculovirus expressing ICP4. MAbs were selected by enzyme-linked immunosorbent assay (ELISA) using MDV-infected and control chick kidney cells as antigens. One of the MAbs, 5H8, recognized an epitope toward the carboxyl terminus of ICP4 based on staining of reticuloendotheliosis virus-transformed cells transfected with full-length and truncated ICP4 constructs. This MAb recognized ICP4 in chicken embryo fibroblasts (CEFs) infected with MDV strains JM16 and HVT but not with SB-1 strain. Using Western blot analysis a protein of 155 kDa was detected in CEFs infected with JM16 and HVT strains.

[Gene frequency of HPA among Hunan population of Han nationality]

We used allele specific primer PCR (ASP-PCR) method to detect the genotype of five major HPA systems among Hunan population of Han nationality. The results showed: The gene frequency of PLA1 was 81.00% and 85.87% for Kob, 71.00% for Baka, 91.00% for Pena, 90.67% for Brb which provided the basis for further clinical application of HPA.

The structural and functional analysis of the hemoglobin D component from chicken

Oxygen binding by chicken blood shows enhanced cooperativity at high levels of oxygen saturation. This implies that deoxy hemoglobin tetramers self-associate. The crystal structure of an R-state form of chicken hemoglobin D has been solved to 2.3-A resolution using molecular replacement phases derived from human oxyhemoglobin. The model consists of an alpha2 beta2 tetramer in the asymmetric unit and has been refined to a R-factor of 0.222 (R-free = 0.257) for 29,702 reflections between 10.0- and 2.3-A resolution. Chicken Hb D differs most from human oxyhemoglobin in the AB and GH corners of the alpha subunits and the EF corner of the beta subunits. Reanalysis of published oxygen binding data for chicken Hbs shows that both chicken Hb A and Hb D possess enhanced cooperativity in vitro when inositol hexaphosphate is present. The electrostatic surface potential for a calculated model of chicken deoxy-Hb D tetramers shows a pronounced hydrophobic patch that involves parts of the D and E helices of the beta subunits. This hydrophobic patch is a promising candidate for a tetramer-tetramer interface that could regulate oxygen binding via the distal histidine.

GRAB proteins, novel members of the NAC domain family, isolated by their interaction with a geminivirus protein

Geminiviruses encode a few proteins and depend on cellular factors to complete their replicative cycle. As a way to understand geminivirus-host interactions, we have searched for cellular proteins which interact with viral proteins. By using the yeast two-hybrid technology and the wheat dwarf geminivirus (WDV) RepA protein as a bait, we have isolated a family of proteins which we termed GRAB (for Geminivirus Rep A-binding). We report here the molecular characterization of two members, GRAB1 and GRAB2. We have found that the 37 C-terminal amino acids of RepA are required for interaction with GRAB proteins. This region contains residues conserved in an equivalent region of the RepA proteins encoded by other viruses of the WDV subgroup. The N-terminal domain of GRAB proteins is necessary and sufficient to interact with WDV RepA. GRAB proteins contain an unique acidic C-terminal domain while their N-terminal domain, of ca. 170 amino acids, are highly conserved in all of them. Interestingly, this conserved N-terminal domain of GRAB proteins exhibits a significant amino acid homology to the NAC domain present in proteins involved in plant development and senescence. GRAB1 and GRAB2 mRNAs are present in cultured cells and roots but are barely detectable in leaves. GRAB expression inhibits WDV DNA replication in cultured wheat cells. Our studies highlight the importance that the pathway(s) mediated by GRAB proteins, as well as by other NAC domain-containing proteins, might have on geminivirus DNA replication in connection to plant growth, development and senescence pathways.

[Optimum choice for the cultivation of CFU-GM in media buffered with HEPES]

The effects of media buffered with HEPES of different concentrations and different incubation periods on the proliferation and differentiation of CFU-GM were studied under the standard condition for culture. The results exhibited that when the incubation period prolonged, the pH values of culture system raised and the colony formation of CFU-GM decreased; the culture system added with proper HEPES buffer solution could maintain and increase the colony formation of CFU-GM, especially the culture system in which the pH value was not adjusted before the experiment. We also found that media buffered with HEPES could change the ratio of different colony types. This showed that media buffered with HEPES could not only stimulate the proliferation of CFU-GM, but also affect its differentiation. The results suggest that media buffered with HEPES are better than those without HEPES for the culture of hematopoietic progenitor cells, and the optimum concentration is 10-20 mmol.L-1.

Evaluation of pulmonary afferent fibers in the nucleus tractus solitarius: a horseradish peroxidase and c-fos like immunohistochemical study in the rat

Wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into the rat lung parenchyma, just beneath the lateral surface of the left upper lobe, in order to demonstrate the pulmonary afferents. This injection resulted in heavy accumulation of labeled fibers in the medial nucleus tractus solitarius (NTS). The labeling in the medial NTS was divided into the ventral and dorsal parts at the level around the obex. Some labeling was found in the commissural and ventrolateral NTS. Further confirmation of the central distribution of these pulmonary afferent fibers was made by the expression of fos-like immunoreactivity (FOS-LI) induced by injection of formalin into the lung. It is concluded that afferents of lung parenchyma terminating predominantly in the medial NTS might come from alveoli and terminal bronchioles, because WGA-HRP and formalin injected into the lung are considered to be confined to the terminal areas of the respiratory tract.

Synthesis and immunosuppressant activity of pyrazole carboxamides

A series of novel pyrazole carboxamides is disclosed that demonstrate strong immunosuppressant activity in rodent and human mixed leukocyte response (MLR) assays (IC50 < 1 microM). The synthesis, biological activity, mode of action, and pharmacokinetic properties of this new lead series are discussed.

Discovery of ascomycin analogs with potent topical but weak systemic activity for treatment of inflammatory skin diseases

Drug therapy for the major inflammatory skin diseases, which include atopic dermatitis, psoriasis and allergic contact dermatitis, is often inadequate due to poor efficacy, toxicity, or both. Much research has focused on the macrolactam T cell inhibitors as a promising new class of agents for immunotherapy, and medicinal chemistry efforts to design novel ascomycin analogs have produced clinically promising agents. A synthetic program to modify the ascomycin nucleus to alter its physicochemical properties and promote systemic clearance is described. A biologic screening strategy to identify analogs with reduced systemic activity and rapid pharmacokinetic elimination led to identification of the clinical candidate, ABT-281. A swine contact hypersensitivity model was used as a stringent indicator of skin penetration as human doses of topical corticosteroids produced inhibition only in the 50% range and ED50 values were 100-fold less potent than in rat. Also, cyclosporine was confirmed to be topically inactive in swine, as seen in human. ABT-281 had topical potency equal to tacrolimus (FK506) despite a severalfold lower potency for inhibiting swine T cells in vitro, consistent with superior skin penetration. ABT-281 was found to have a shorter duration of action after i.v. dosing in monkeys using an ex vivo whole blood IL-2 production assay. Systemic potency was reduced by 30-fold or more in rat popliteal lymph node hyperplasia and contact hypersensitivity assays. Following i.v. or i.p. administration in the swine contact hypersensitivity model, ABT-281 was 19- and 61-fold less potent, respectively, than FK506. Pharmacokinetic studies showed that ABT-281 had a shorter half life and higher rate of clearance than FK506 in all three species. The potent topical activity and reduced systemic exposure of ABT-281 may thus provide both efficacy and a greater margin of safety for topical therapy of skin diseases.

Occlusion of the femoral artery induced fos-like immunoreactive neurons in the lateral habenular nucleus projecting to the midbrain periaqueductal gray in the rat

Wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) injection into the midbrain periaqueductal gray (PAG) resulted in heavy accumulation of retrogradely labeled neurons in the lateral habenular nucleus (LHb) bilaterally. When the left femoral artery was persistently ligated for 2 h, the expression of Fos-like immunoreactivity (FOS-LI) was also found bilaterally in the LHb. In the present study, by combining the retrograde labeling method of injecting WGA-HRP into the PAG and the immunohistochemical staining of the FOS-LI neurons in the LHb induced by occlusion of the femoral artery, it was demonstrated that there are neurons containing both HRP labeling and FOS-LI. These neurons appeared to be located mainly in the medial part and posterior half of the LHb, and constitute about 24% of the total number of all labeled cells.

Distribution of F4/80-positive cells in developing ovaries in the mouse

The mature ovary contains a large number of macrophages. In the present study, the distribution of macrophages in murine ovaries at various developmental stages was immunohistochemically studied using a monoclonal antibody against F4/80, a highly specific antigen of murine macrophages. The results showed that definite F4/80-positive stains were hardly detectable in ovaries on day 0 after birth. On day 7, a few F4/ 80-positive cells could be identified between the developing follicles. The positive stains were irregular in shape and showed little physical contact with the primordial or primary follicles. By days 14 and 21, when the theca cell layers of growing follicles were developing, the positive cells had extended or elongated to surround the cell layer. On day 28, besides the presence of elongating positive cells surrounding the growing follicles, irregularly shaped F4/80-positive cells became apparent in the interstitium between the growing follicles and also in the capsular tissues. Thereafter, positive cells with stellate appearance were detected in the corpora lutea, which first developed around 6 weeks of age. Although the positive cells were homogenously distributed in the corpora lutea in virgin adults, only a few sporadic positive cells were found there in pregnant mice. However, the positive cells infiltrated into the corpora lutea again in the postpartum period. These results show that ovarian macrophages exhibit dramatical changes in their distribution from neonatal to postpartum periods.

Brainstem projections of sensory fibers of the lung: a horseradish peroxidase and c-fos-like immunohistochemical study in the rat

The brainstem projections of sensory fibers of the lung were determined in the rat by using the horseradish peroxidase (HRP) and c-fos immunohistochemical methods. Wheat germ agglutinin conjugated HRP (WGA-HRP) was injected into the parenchyma of the upper lobe of the left lung. This injection resulted in anterograde labeling in the nucleus of the tractus solitarius (NTS), area postrema (AP) and external cuneate nucleus (ECu) with slightly ipsilateral predominance. It was of interest that these labeled sensory fibers are heavily accumulated in the medial subnucleus at the rostral pole of the NTS and in the commissural subnucleus at the caudal pole. In particular, labeled fibers in the medial subnucleus were characterized by division into the ventral and dorsal portions. After formalin was injected into the parenchyma of the upper lobe of the left lung, the expression of c-fos-like immunoreactivity (FOS-LI) was observed in three nuclei of the brainstem mentioned above. In addition, this experiment resulted in the expression in the ventrolateral medulla, nucleus raphe pallidus and dorsal motor nucleus of vagus nerve bilaterally. With respect to the number of the immunoreactive cells, we could draw the conclusion that the most optimum time to induce the expression of FOS-LI is between 1.5 h and 2.0 h after noxious stimuli.

Patterns of efferent lymphatics of the mouse testis

Previous studies in the rat demonstrated that lymph vessels arise from various sites in the testis and then anastomose to form the main lymph trunk toward the testicular artery. Although mice are as commonly used in the laboratory as the rat, precise knowledge concerning their testicular lymphatics has not been established. In the present study, the patterns of testicular lymphatic drainage in the mouse were examined using local injection of India ink into the testicular parenchyma. The results demonstrated that, besides the lymph trunk surrounding the testicular artery, a lymphatic drainage route running along the ductus deferens is also present.

Effects of age on the posttranscriptional regulation of CCAAT/enhancer binding protein alpha and CCAAT/enhancer binding protein beta isoform synthesis in control and LPS-treated livers

The CCAAT/enhancer binding protein alpha (C/EBPalpha) and CCAAT/enhancer binding protein beta (C/EBPbeta) mRNAs are templates for the differential translation of several isoforms. Immunoblotting detects C/EBPalphas with molecular masses of 42, 38, 30, and 20 kDa and C/EBPbetas of 35, 20, and approximately 8.5 kDa. The DNA-binding activities and pool levels of p42(C/EBPalpha) and p30(C/EBPalpha) in control nuclear extracts decrease significantly whereas the binding activity and protein levels of the 20-kDa isoforms increase dramatically with LPS treatment. Our studies suggest that the LPS response involves alternative translational initiation at specific in-frame AUGs, producing specific C/EBPalpha and C/EBPbeta isoform patterns. We propose that alternative translational initiation occurs by a leaky ribosomal scanning mechanism. We find that nuclear extracts from normal aged mouse livers have decreased p42(C/EBPalpha) levels and binding activity, whereas those of p20(C/EBPalpha) and p20(C/EBPbeta) are increased. However, translation of 42-kDa C/EBPalpha is not down-regulated on polysomes, suggesting that aging may affect its nuclear translocation. Furthermore, recovery of the C/EBPalpha- and C/EBPbeta-binding activities and pool levels from an LPS challenge is delayed significantly in aged mouse livers. Thus, aged livers have altered steady-state levels of C/EBPalpha and C/EBPbeta isoforms. This result suggests that normal aging liver exhibits characteristics of chronic stress and a severe inability to recover from an inflammatory challenge.

[Preliminary experiment on selection of oral hygienic cleanser]

The effectiveness of three commercial chewing gums ("Hua Aikang","Cao Shanhu" and "Poli") and brushing with toothpaste on the elimination of dental plaque was observed in 31 healthy males (aged 19-25 years). Before and after chewing or brushing, evaluation of oral taste and examination of plaque were performed. The result showed that the oral taste after chewing, "hua aikang" was the best, then "po li" and "cao shanhu"; plaque indexes were substantially reduced by all four kinds of treatment (P < 0.001) as compared with the pretest values, however "hua aikang" demonstrated a better effectiveness (P < 0.001). It also indicates that plaque index is an important index revealing the hygiene status.

The maize retinoblastoma protein homologue ZmRb-1 is regulated during leaf development and displays conserved interactions with G1/S regulators and plant cyclin D (CycD) proteins

Recent discoveries of plant retinoblastoma (Rb) protein homologues and D-type cyclins suggest that control of the onset of cell division in plants may have stronger parallels with mammalian G1/S controls than with yeasts. In mammals, the Rb protein interacts specifically with D-type cyclins and regulates cell proliferation by binding and inhibiting E2F transcription factors. However, the developmental role of Rb in plants and its potential interaction with cell cycle regulators is unknown. We show that the maize Rb homologue ZmRb-1 is temporally and spatially regulated during maize leaf development. ZmRb-1 is highly expressed in differentiating cells, but almost undetectable in proliferating cells. In vitro, both ZmRb-1 and human Rb bind all classes of plant D-type cyclins with the involvement of a conserved N-terminal Leu-x-Cys-x-Glu (LxCxE) Rb-interaction motif. This binding is strongly reduced by mutation of the conserved Cys-470 of ZmRb-1. ZmRb-1 binds human and Drosophila E2F, and inhibits transcriptional activation of human E2F. We also show that ZmRb-1 is a good in vitro substrate for all human G1/S protein kinases. The functional conservation of proteins that control the G1/S transition in mammals and plants points to the existence of plant E2F homologues. We conclude that evolution of Rb and cyclin D proteins occurred after separation of the fungi from the higher eukaryotic lineage, but preceded the divergence of plant and animal kingdoms.

Postnatal development of Leydig cells in the opossum (Monodelphis domestica): an immunocytochemical and endocrinological study

This study involved characterization of Leydig cells of the opossum Monodelphis domestica, functionally by immunocytochemical identification of the enzyme 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and by measurement of testosterone levels using RIA. Immunostaining for 3 beta-HSD was first detected in a few Leydig cells on Day 16, was increased by Day 24, reached a peak at 4 mo, and was present even in senescent (3 yr) animals. Plasma testosterone was first measurable (0.35 nM) at prepuberty (3.5 mo). Prior to that, plasma testosterone concentrations were uniformly below the level of detection (< 0.3 nM) in both sexes from Day 5 to 2.5 mo. By 4 mo (puberty), plasma testosterone levels in males had risen significantly to 1.53 +/- 0.35 nM, continuing to increase to 1.79 +/- 0.4 nM at 6 mo and peaking at 2.71 +/- 0.29 nM in the adult (1-2 yr). Ovarian testosterone concentrations were consistently lower than those in the testis, as were those of adrenals of both sexes. Thus the testis would appear to be the major source of androgen production throughout life in this species. Our immunocytochemical study suggests that in Monodelphis, puberty is reached at 4 mo, and this was further supported by a rise in circulating testosterone levels at this time.