Alteration in L-DOPA evoked dopamine and DOPAC output under conditions of impaired vesicular dopamine storage

We examined the effect of L-dihydroxyphenylalanine (L-DOPA) infusion in vitro upon dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) output from superfused corpus striatum of vehicle and reserpine or tetrabenazine (TBZ) treated male rats. Specifically, we tested the effects of two 20-min infusions of L-DOPA (5 uM) upon DA and DOPAC output (pg/mg/min) in reserpine (5 mg/kg, i.p., 24 hours before sacrifice; n=11), TBZ (30 mg/kg, i.p. 1 hour before sacrifice; n=8) or vehicle (n=21) treated rats. There was an overall significantly higher L-DOPA evoked DA output from the vehicle (12.22+/-1.74) versus reserpine (4.39+/-2.40) (p < 0.05), but not TBZ (9.16+/-2.81) treated rats. In addition, the DA response to the second L-DOPA infusion was significantly increased over that of the first response in the vehicle (9.40+/-2.11 vs. 15.04+/-2.78) (p < 0.05), but not reserpine or TBZ treated rats. The overall DOPAC outputs did not achieve a statistically significant difference among all treatment groups. However, the DOPAC outputs following the second L-DOPA infusion were significantly reduced in reserpine (41.15+/-6.10 vs. 20.27+/-4.54) and TBZ (21.38+/-4.41 vs. 10.87+/-2.36) (both p < 0.05), but not vehicle (28.99+/-4.00 vs. 24.91+/-4.78) treated rats. We conclude that: 1) the storage capacity of DA neurons is one of the important elements involved in affecting L-DOPA's effects upon DA and DOPAC output, 2) the shunting of storage to metabolism may represent a common characteristic in impaired nigrostriatal dopaminergic system, and 3) TBZ may operate differently from reserpine in the nigrostriatal dopaminergic system.

[Refractory anemia and preleukemia: an analysis of 92 cases]

OBJECTIVE

To investigate the relationship between MDS-RA (refractory anemia subtype of myelodysplastic syndromes) and preleukemia (PL).

METHODS

Hematological parameters of 86 RA and 6 PL patients were retrospectively analyzed.

RESULTS

Thirty-four RA cases (39.53%) transformed into acute leukemia (AL), RA with excess blasts (RAEB), or RAEB in transformation (RAEB-t). As compared with 52 non-transformed RA cases, the transformed cases showed the following hematological features: 1. higher frequencies of immature granulocytes (P < 0.005), erythroblasts (P < 0.05) and megaloerythrocytes (P < 0.05), and higher granulocyte nuclear lobulation (P < 0.001) in peripheral blood; 2. higher percentages of early erythroid and granulocytic lineages (P < 0.05), and higher frequencies of erythroblasts with multiple nuclei (P < 0.05), pseudo Pelger-Huet abnormality (P < 0.05), and micromegakaryocytes (P < 0.005) in bone marrow.

CONCLUSION

There is a higher overlap between RA and PL; the above hematological features may be useful for predicting the transformation of RA patients. Based on those findings, a score system for predicting the transformation of RA was proposed.

Discussion to the equivalent point realized by the two polarized beams in AOTF system

By an accurate theoretical analysis, an equivalent point is found where the filtered optic wave lengths of the two acoustic-optic reactions of "e in o out" and "o in e out" are the same with the same acoustic frequency. Two cases of d=0 and d10 are discussed and compared. The merits of the equivalent point is discussed in different points of view. The discussions conclude that the parameters set around the equivalent point leading to the optimum designing.

Selective induction of protective MHC class I-restricted CTL in the intestinal lamina propria of rhesus monkeys by transient SIV infection of the colonic mucosa

The identification of mucosal immune responses required for protection against sexual transmission of HIV is essential for the development of an efficacious vaccine. To gain a better understanding of these responses, we have characterized the immune responses in the lamina propria (LP) and epithelium of the jejunum, the mesenteric lymph nodes, and peripheral blood (PBMC) of 11 rhesus monkeys following colonic exposure to two molecular clones of SIV. Two monkeys had no signs of infection. Three monkeys became persistently infected. Transient infections, characterized by the sporadic detection of virus in the periphery and/or detection of SIV-specific immune responses in either the gut-associated tissues or PBMC, were induced in six of the monkeys. One persistently infected and three transiently infected monkeys had high levels of SIV env-specific MHC class I restricted CTL in the jejunal LP. Another transiently infected monkey had SIV-specific IgA secreting B cells in the LP. Three or six months postexposure, these animals and four naive controls were challenged intracolonically with the heterologous primary isolate, SIV/DeltaB670. All four monkeys with strong SIV env-specific MHC-restricted CTL in the LP were protected, whereas none of the naive controls or the remaining seven monkeys with little or no CTL in the LP were protected. These experiments provide the first direct evidence that transient mucosal infection can induce SIV-specific immunity that remains localized to the gut-associated tissues. Furthermore, a strong correlation between SIV env-specific MHC-restricted CTL in the LP and protection against colonic mucosal challenge was observed.

Human preembryo development on autologous endometrial coculture versus conventional medium

OBJECTIVE

To evaluate the effect of autologous endometrial coculture versus conventional medium on preembryo development.

DESIGN

Controlled systematic clinical study.

SETTING

University-based IVF center.

PATIENT(S)

Women with a history of failed IVF-ET with poor preembryo quality.

INTERVENTION(S)

Patients underwent a luteal phase endometrial biopsy. The tissue then was digested enzymatically, and the stromal and glandular cells were separated by differential sedimentation rates. These cells were cultured to confluence, released, and then cryopreserved until the patient's IVF-ET cycle. All normally fertilized oocytes then were allocated systematically to growth on autologous endometrial coculture or conventional medium until transfer on day 3.

MAIN OUTCOME MEASURE(S)

Preembryo blastomere numbers and cytoplasmic fragmentation rates were measured.

RESULT(S)

Forty-two women underwent 44 cycles of IVF-ET. In the morning on day 3, the mean (+/-SD) number of blastomeres and cytoplasmic fragments per preembryo on coculture compared with conventional medium was 5.9+/-1.5 versus 5.5+/-1.4 and 21%+/-13% versus 24%+/-11. At transfer the mean (+/-SD) number of blastomeres per preembryo on coculture was 7.4+/-1.3 versus 6.7+/-1.9 on conventional medium.

CONCLUSION(S)

There was a significant improvement in the mean (+/-SD) number of blastomeres per preembryo and decrease in the fragmentation rate for preembryos on autologous endometrial coculture compared with noncocultured preembryos from the same patient.

Detection of Neisseria gonorrhoeae infection by ligase chain reaction testing of urine among adolescent women with and without Chlamydia trachomatis infection

BACKGROUND AND OBJECTIVES

Culture, the conventional method for detection of Neisseria gonorrhoeae, requires invasive sampling and stringent specimen transport conditions. The recently developed ligase chain reaction test (LCR; Abbott Laboratories; North Chicago, IL) allows noninvasive sampling and stable transport conditions, but has not been evaluated with specimens from adolescent populations.

GOAL OF THIS STUDY

To perform a comparative evaluation of a commercial LCR test and culture for the diagnosis of N. gonorrhoeae in adolescent women.

STUDY DESIGN

Urine and endocervical swab specimens from 330 teenage women seen in two public health adolescent clinics were tested by LCR and culture. For resolution of discordant results, a polymerase chain reaction (PCR) test was developed that directly amplifies N. gonorrhoeae DNA from urine samples processed for LCR.

RESULTS

Thirty-one of 330 (9.4%) cervical specimens were culture-positive for N. gonorrhoeae, and 30 of 330 (9.1%) urine specimens were positive by LCR. After resolution of 13 discordant results, the sensitivity, specificity, and positive and negative predictive values of LCR for urine were 88.2%, 100%, 100%, 98.7%, respectively, and for culture of endocervical specimens were 82.3%, 98.9%, 90.3% and 98%, respectively.

CONCLUSIONS

Although more expensive than culture, LCR offers a sensitive means for the detection of N. gonorrhoeae in urine samples and may be useful for this purpose in settings where pelvic examinations are difficult to perform and simultaneous detection of N. gonorrhoeae and Chlamydia trachomatis is advantageous.

Improving the fixation method for preimplantation genetic diagnosis by fluorescent in situ hybridization

PURPOSE

Our purpose was to modify a fixation method using Tween-20 and HCl (TH) and to compare it with a protocol using methanol and acetic acid (MA) for the improvement of preimplantation genetic diagnosis by fluorescence in situ hybridization (FISH).

METHODS

Single blastomeres were allocated to either the TH or the MA procedure. The two methods were compared to evaluate efficiency of fixation and the intensities of FISH signals.

RESULTS

With the TH method, 123 (93.9%) of 131 blastomeres were fixed, while only 95 (78.5%) of 121 were fixed with MA. Average scores for the intensity of FISH signals were significantly stronger for TH than for MA (P < 0.05). There was also a significant difference in signal intensity scores between the two methods for type-3 nuclei.

CONCLUSIONS

Our results indicate that not only are fewer nuclei lost during fixation but also stronger FISH signals can be obtained with the TH method. Thus, modified TH can improve the overall efficiency of preimplantation genetic diagnosis.

Atomic force microscopy used for the surface characterization of microcapsule immunoisolation devices

The surface morphology of the microcapsule used as a bioartificial pancreas was examined by atomic force microscopy (AFM) under ambient conditions in a liquid environment. The standard contact mode was used for imaging. The capsules exhibited different morphologies and surface roughness depending on the composition of the cation solution: namely, the mole ratio of antigelling and gelling cations [Na+]/[Ca2+]. Surface roughness parameters obtained by AFM measurements provide quantitative information on the surface properties of the capsular membrane. In this respect, AFM can be considered a valuable technique complementary to optical microscopy in providing feedback for capsule optimization.

[c-erbB2 gene amplification in human primary epithelial ovarian cancer and its clinical significance]

OBJECTIVE

To study c-erbB2 gene amplification in human primary epithelial ovarian cancer and its clinical significance.

METHODS

One hundred forty nine samples of primary epithelial ovarian tumors, including 34 beign tumors, 7 borderline tumors and 108 carcinoma, were studied for c-erbB2 gene amplification by Southern blot analysis.

RESULTS

c-erbB2 gene amplification was detected in 35 (32.4%) of the 108 cases with primaey epithelial ovarian carcinoma, while all cases with beign tumors and borderline lesions were negative (P < 0.001). There was a strong correlation between c-erbB2 gene amplification and FIGO stage of human ovarian carcinoma (P = 0.026), degree of cell differentiation (P = 0.011) and the size of residual tumor (P < 0.001). Univariate and multivariate analysis showed that c-erbB2 gene amplification was an independent prognostic factor. The average 3-year survival rate was 28.4% in patients with gene amplification and 57.7% in patients without gene amplification(P = 0.016).

CONCLUSION

c-erbB2 gene amplification occurs almost in 1/3 of the patients with ovarian carcinoma examined. Ovarian carcinoma with c-erbB2 gene amplification is highly malignant and associated with poor prognosis.

[An endometrium morphometry study on ovariectomized rats subjected to nilestriol and estradiol replalcement therapies]

This study was designed to evaluate the effect of estrogen on rat endometrium and compare the results of Nilestriol and Estradiol replacement therapies for preventing osteoporosis in ovariectomized rats. Forty 4-month old SD female rats were randomly divided into four groups, namely sham operation, bilateral ovariectomy, ovariectomy plus supplementary ethinyl estradiol (0.2 microgram/100 g B. W. qd x 5), and ovariectomy plus supplementary Nilestriol (0.15 mg/100 g B. W. once a week). Computerized image analyzer was used to evaluate the endomitrial pathological changes 10 weeks later. The results showed an atrophied endometrium in ovariectomized group, a slightly proliferative endometrium in Nilestriol treated group, and a markedly proliferative endometrium with local atypical hyperplasia in estradiol treated group. The difference between group 3 and group 4 in morphometry was significant (P < 0.5). These suggest the relative safety of Nilestriol replacement therapy for preventing menopausal osteoporosis.

Experimental leprosy in rhesus monkeys: transmission, susceptibility, clinical and immunological findings

A total of 46 Rhesus monkeys (RM) was inoculated with Mycobacterium leprae (ML) and followed clinically and immunologically for extended periods. Twenty-one (45.7%) of the RM developed leprosy spanning the known leprosy spectrum, with six of 21 (28.6%) having disease in the borderline lepromatous to lepromatous area of the spectrum. RM with paucibacillary forms of leprosy produced predominantly IgG anti-phenolic glycolipid (PGL-I) antibodies and positive lepromin skin test and/or in vitro blastogenesis responses; IgM anti-PGL-I predominated in animals with BB-LL leprosy and correlated with negative immune responses to lepromin. IgG anti-PGL-I antibodies persisted in a number of RM for several years without histopathological evidence of leprosy, suggesting possible persisting subclinical infection. The data show that RM are a valuable model for the study of leprosy. Eleven of the 46 RM were inoculated with ML from sources infected with simian immunodeficiency virus (SIV), the monkey counterpart to the human immunodeficiency virus (HIV). The possible effect of SIV on the clinical outcome of ML infection could not be determined due to insufficient numbers of animals to yield statistically significant results.

Stimulated release of fluorescently labeled IgE fragments that efficiently accumulate in secretory granules after endocytosis in RBL-2H3 mast cells

Sensitization of RBL-2H3 mast cells with monomeric fluorescein-5-isothiocyanate (FITC)-labeled immunoglobulin E (IgE) results in slow but highly efficient accumulation of labeled IgE fragments in a pool of acidic peripheral vesicles that are visible by fluorescence microscopy after raising endosomal pH with ammonium chloride. Stimulation of cells containing these FITC-IgE fragments by aggregation of high affinity receptors for IgE (FcepsilonRI) or by Ca2+ ionophore and phorbol 12-myristate 13-acetate results in release of FITC fluorescence from the cells, which can be monitored continuously with a spectrofluorometer. The fluorescence release process corresponds to cellular degranulation: it is prevented under conditions that prevent stimulated beta-hexosaminidase release, and these two processes exhibit the same antigen dose-dependence and kinetics. Pulse-chase labeling reveals that aggregation of FITC-IgE bound to FcepsilonRI at the cell surface causes internalization and delivery to the regulated secretory vesicles with a high efficiency similar to monomeric IgE-FcepsilonRI, but more rapidly. Binding of Cy3-modified IgE to FcepsilonRI results in labeling of the same secretory vesicles as in FITC-IgE-sensitized cells, and these Cy3-labeled vesicles can be observed by fluorescence microscopy without neutralization of intracellular compartments. Simultaneous three-photon microscopy of serotonin fluorescence and two-photon microscopy of Cy3 fluorescence reveals that these Cy3-labeled vesicles coincide with serotonin-labeled secretory granules. After stimulation of the cells via aggregation of IgE-FcepsilonRI or addition of Ca2+ ionophore and phorbol 12-myristate 13-acetate, depletion of the Cy3 label from the intracellular vesicles is observed with confocal microscopy. These results provide strong evidence for the lysosomal nature of secretory granules in these cells. In addition, they provide the basis for a direct, real-time method for monitoring single cell degranulation.

Histamine induces nuclear factor of activated T cell-mediated transcription and cyclosporin A-sensitive interleukin-8 mRNA expression in human umbilical vein endothelial cells

The nuclear factor of activated T cells (NFAT) mediates a cyclosporin A (CsA)- and FK506-suppressible transcriptional program in lymphocytes after antigen-stimulated phospholipase C activation. Nonlymphoid cells also express NFAT isoforms, raising the possibility that these isoforms can be regulated by other extracellular stimuli. This study sought to determine whether histamine can trigger NFAT-mediated transcription in human umbilical vein endothelial cells (HUVEC), using a retrovirus-based luciferase reporter driven by a well characterized, NFAT-specific enhancer. Luciferase levels are induced up to 60-fold over basal levels after costimulation of HUVEC with Ca2+-mobilizing drugs and a phorbol ester, a response that is 20-fold greater than that observed when HUVEC are stimulated with either drug alone. These synergistic responses are inhibited in cells treated with CsA. CsA and FK506 also inhibit the luciferase response to histamine, indicating that histamine can induce NFAT-mediated transcription in HUVEC. To identify candidate genes in HUVEC that might be regulated by NFAT, the expression of several chemokine mRNAs was measured after histamine treatment. Of the mRNAs tested, only those encoding monocyte chemotactic protein-1 (approximately 2-fold over basal) and interleukin-8 (approximately 6-fold over basal) are induced by histamine; both of these responses are suppressed by CsA and FK506. The H1 histamine receptor antagonist chlorpheniramine, but not the H2 receptor antagonist ranitidine, blocks the effects of histamine in this preparation. These data provide the first evidence for a physiological inducer of NFAT-mediated transcription in endothelial cells and support the hypothesis that NFAT participates in H1 histamine receptor-induced interleukin-8 gene expression.

[Allele-specific chromosome 3p25 deletion detected by PCR-LOH analysis in non-small cell lung cancer.]

BACKGROUND

To ascertain whether the loss of heterozygosity (LOH) of allele on chromosome 3p25 region is associated with non-small cell lung cancer (NSCLC) .

METHODS

3p25 LOH was analysed in patients with NSCLC by polymerase chain reaction-based assays for dinucleatide repeat polymorphisms.

RESULTS

Eighty out of 158 (50. 6 %) cancer tissues of NSCLC were found to have 3p25 LOH , but no 3p25 LOH was observed in 5 normal fetal lung tissues and 4 tissues of the benign lung neoplasms. The deletion was detected in 62.0% of adenocarcinoma and 43.2% of the squamous carcinoma , indicating that the former was significantly higher than the latter ( P < 0. 05) . Loss frequences for TNM stages were further observed in 52.2% , 45.0% and 52.8% of the cases for stage I, II and III respectively , and these data showed no significant relationship between the loss frequence and TNM staging of NSCLC ( P > 0. 05) .

CONCLUSIONS

Above findings display that 3p25 LOH appear to be a common structural alteration occurred in NSCLC and there may be suppressor genes relevant to the carcinogenesis of the lung in 3p25 region.

[Study on expression of Evi1 and MDS1-Evi1 genes in myelodysplastic syndromes]

OBJECTIVE

To investigate expression of Evi1 and MDS1-Evi1 genes in myelodysplastic syndromes (MDS) and its role in pathogenesis of MDS.

METHODS

Expression of Evi1 and MDS1-Evi1 genes was examined in 31 MDS, 11 post MDS acute myeloid leukemia (post MDS AML) and 34 de novo AML patients by a semi-quantitative RT-PCR.

RESULTS

Evi1 expression was not detected in 8 normal controls, but low MDS1-Evi1 expression levels (MDS1-Evi1/GAPDH < 0.1) detected in 3 of the 8 controls. Evi1 mRNA was expressed in 1 of 8 RA, 8 of 13 RAEB and 6 of 9 RAEB-t patients, and the percentage of Evi1 expression in RAEB(t) patients was higher than that in RA(P < 0.05). MDS1-Evi1 expression was detected in 5 of 8 RA, 9 of 13 RAEB and 5 of 9 RAEB-t patients, and MDS1-Evi1 expression levels (MDS1-Evi1/GAPDH > 0.1) in the patients were markedly higher than those in the controls. Evi1 expression was gradually increased in 4 of 5 RAEB-t patients with transformation from MDS to AML. The percentages of Evi-1 and MDS1-Evi1 expression in post MDS AML patients were higher than those in de novo AML (P < 0.01 and P < 0.05, respectively). The numbers of colony formation of progenitor cells in Evi1 and MDS1-Evi1-positive MDS patients were decreased as compared with Evi1 and MDS1-Evi1-negative patients.

CONCLUSION

Abnormal expression of Evi1 and overexpression of MDS1-Evi1 might play a certain role in the pathogenesis or progression of MDS and post MDS AML.

Calcium oscillations increase the efficiency and specificity of gene expression

Cytosolic calcium ([Ca2+]i) oscillations are a nearly universal mode of signalling in excitable and non-excitable cells. Although Ca2+ is known to mediate a diverse array of cell functions, it is not known whether oscillations contribute to the efficiency or specificity of signalling or are merely an inevitable consequence of the feedback control of [Ca2+]i. We have developed a Ca2+ clamp technique to investigate the roles of oscillation amplitude and frequency in regulating gene expression driven by the proinflammatory transcription factors NF-AT, Oct/OAP and NF-kappaB. Here we report that oscillations reduce the effective Ca2+ threshold for activating transcription factors, thereby increasing signal detection at low levels of stimulation. In addition, specificity is encoded by the oscillation frequency: rapid oscillations stimulate all three transcription factors, whereas infrequent oscillations activate only NF-kappaB. The genes encoding the cytokines interleukin (IL)-2 and IL-8 are also frequency-sensitive in a way that reflects their degree of dependence on NF-AT versus NF-kappaB. Our results provide direct evidence that [Ca2+]i oscillations increase both the efficacy and the information content of Ca2+ signals that lead to gene expression and cell differentiation.

Kinetics of multivalent antigen DNP-BSA binding to IgE-Fc epsilon RI in relationship to the stimulated tyrosine phosphorylation of Fc epsilon RI

Multivalent DNP-BSA is commonly used to cross-link anti-DNP IgE bound to Fc epsilon RI to stimulate cellular responses, although key features of the binding process are unknown. Fluorescence quenching can be used to study the kinetics of DNP-BSA binding to FITC-IgE. We observe that DNP-BSA binds more slowly to IgE than does an equimolar amount of a monovalent DNP ligand, suggesting that the average effective number of DNP groups per BSA is less than one. The binding data are well described by a transient hapten exposure model in which most of the DNP groups are unavailable for binding but have some probability of becoming exposed and available for binding during the time of the binding measurement. Additional experiments indicate that, for suboptimal to optimal concentrations of DNP-BSA, most of the FITC fluorescence quenching on the cell surface is due to cross-linking events. With these concentrations at 15 degrees C, the kinetics of FITC fluorescence quenching by DNP-BSA correlates with the kinetics of DNP-BSA-stimulated tyrosine phosphorylation of Fc epsilon RI. At 35 degrees C, the phosphorylation kinetics are biphasic during the time period in which cross-linking continues to increase. Our results establish a quantitative relationship between the time-course for cross-linking by multivalent Ag and Fc epsilon RI-mediated signaling, and they provide the means to predict the kinetics of cross-linking under a wide variety of conditions.

Transmission and natural regulation of infection with Ascaris lumbricoides in a rural community in China

A longitudinal study on a cohort of 215 people who remained untreated from June 1993 to June 1994 was carried out using fecal egg counts to examine the course of transmission and aspects of the natural regulation of the infection with Ascaris lumbricoides. The results indicate that the parasite population remained relatively stable during the years since overall prevalence remained steady above 60%. About 40% of the people in the cohort retained their infection intensity status throughout the year, in terms of light, medium, and heavy infections. The regulation of infection in the population could be attributed to the tendency for the loss of worms from people with initial light infections and the movement to medium infection intensity status of people with both light and heavy infections. Compared with adults, children showed a stronger tendency of retaining initial medium infections but weaker tendencies for keeping initial light infections and clearing themselves of infection. Predisposition to light and medium infections was detected in people who had experienced an uninfected period of 4-12 mo before reinfection was established.

Protective immunization of monkeys with BCG or BCG plus heat-killed Mycobacterium leprae: clinical results

Rhesus and sooty mangabey monkeys (RM and SMM) were vaccinated and boosted with BCG or BCG + low dose (LD) or high dose (HD) heat-killed Mycobacterium leprae (HKML). One group was not vaccinated. Except for a group of controls, all monkeys were challenged with live M. leprae. All animals were studied longitudinally to determine antileprosy protective efficacy. BCG reduced the numbers of RM with histopathologically-diagnosed leprosy by 70% and slowed and ameliorated the appearance of symptoms. BCG + LDHKML reduced the number of RM with leprosy by 89% and BCG + HDHKML by 78%. BCG did not protect SMM from developing leprosy, but disease progress was slowed; disease in SMM was exacerbated by the addition of HKML to the vaccine. RM, as a species, are prone to paucibacillary (PB) forms of leprosy, whereas SMM are prone to multibacillary (MB) forms. Thus, BCG vaccination offers significant protection from clinical disease and slows/ameliorates the rate of progression/degree of disease at the PB end and appears to at least ameliorate symptoms at the MB end of the leprosy spectrum. BCG + HKML protects at the PB end and exacerbates disease progress at the MB end of the leprosy spectrum.

Impaired responses to Mycobacterium leprae antigens in rhesus monkeys experimentally inoculated with simian immunodeficiency virus and M. leprae

Seven of eight rhesus monkeys (RM) coinfected with simian immunodeficiency virus (SIV) and Mycobacterium leprae harboured acid-fast bacilli (AFB) at sites of dermal inoculation and/or at disseminated sites at times of humane sacrifice (up to 270 days post-M. leprae inoculation) due to SIV-induced debilitation or, in one long term survivor's case, to date over 3 years post-M. leprae inoculation. Detectable AFB were cleared in biopsies of inoculation sites of RM inoculated with M. leprae alone after 63 days postinoculation; these sites have, so far, remained AFB-negative, thereafter. Compared to animals infected with M. leprae alone, RM coinfected with SIV plus M. leprae showed: 1, completely suppressed serum antibody responses to M. leprae-specific PGL-I antigen, but strong anti-SIV Gp120 antibody responses; 2, impaired sensitization of blood mononuclear cells (MNC) to in vitro recognition of M. leprae-specific antigens in blastogenic stimulation assays; 3, impaired in vitro responses of blood MNC to nonspecific (ConA) blastogenic stimuli; and 4, early post-M. leprae inoculation, there was a significant incremental diminution of percentages of blood CD4+CD29+ T-cells in addition to the existing SIV-induced diminished percentages of CD4+CD29+ T-cells. The results indicate that humoral and cellular immune responses to M. leprae antigens are compromised in M. leprae-inoculated RM previously infected with SIV. These results provide an immunologic basis for the demonstration of enhanced M. leprae persistence or leprosy susceptibility in SIV-M. leprae coinfected RM.

Alteration of alpha1-adrenoceptor subtypes in aortas of 12-month-old spontaneously hypertensive rats

Alterations in alpha1-adrenoceptor subtypes in aortas from 12-month-old spontaneously hypertensive rats (SHR) were studied in functional studies and RNase protection assays. The norepinephrine-induced contraction, including maximum response and pD2 values, was not significantly different between the SHR and age-matched Kyoto Wistar (WKY) rats. The pA2 values of the alpha1D-adrenoceptor subtype-selective antagonist BMY7378 (8-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-8-azaspiro(4.5)dec ane-7,9-dionedihydrochloride) were increased from 8.10 +/- 0.12 in WKY rats to 8.45 +/- 0.13 in SHR (P < 0.05). The pA2 values of the alpha1A-adrenoceptor subtype-selective antagonist RS-17053 (N-[2-(2-cyclopropylmethoxyphenoxy)ethyl]-5-chloro-alpha,alpha-dim ethyl-1H-indole-3-ethanamine hydrochloride) were reduced from 8.52 +/- 0.20 in WKY rats to 7.82 +/- 0.18 in SHR (P < 0.05), whereas the pA2 values of the alpha1A/alpha1D-adrenoceptor subtype-selective antagonist WB4101 (2-(2,6-dimethoxphenoxyethyl)-aminomethyl-1,4 benzodioxane) were not significantly different between WKY rats and SHR (9.05 +/- 0.22 versus 9.27 +/- 0.15, P > 0.05). Preincubation of preparations in 50 microM chloroethylclonidine for 30 min irreversibly inhibited the norepinephrine-induced response more profoundly in aortas from SHR than in aortas from WKY rats. The results of RNase protection assays showed that mRNAs for alpha1A- and alpha1B-adrenoceptor subtypes were decreased and that mRNA for the alpha1D-adrenoceptor subtype was increased in aortas from SHR compared with WKY rats. The results suggested that the alpha1A-adrenoceptor subtype was decreased and the alpha1D-adrenoceptor subtype was increased in aortas of 12-month-old SHR.

Structure-activity studies of fluoroalkyl-substituted gamma-butyrolactone and gamma-thiobutyrolactone modulators of GABA(A) receptor function

Dihydro-2(3H)-furanones (gamma-butyrolactones) and dihydro-2(3H)-thiophenones (gamma-thiobutyrolactones) containing fluoroalkyl groups at positions C-3, C-4, and C-5 of the heterocyclic rings were prepared. The anticonvulsant/convulsant activities of the compounds were evaluated in mice. Brain concentrations of the compounds were determined and the effects of the compounds on [35S]-tert-butylbicyclophosphorothionate ([35S]TBPS) binding to the picrotoxin site on GABAA receptors were investigated. The effects of the compounds on GABAA receptor function were studied using electrophysiological methods and cultured rat hippocampal neurons. Fluorination at C-3 results in either subtle or pronounced effects on the pharmacological activity of the compounds. When hydrogens are replaced with fluorines at the methylene carbon of an ethyl group, as in 3-(1,1-difluoroethyl)dihydro-3-methyl-2(3H)-furanone (1), the anticonvulsant actions of the compound are not much changed from those found for the corresponding alkyl-substituted analogue. In marked contrast, fluorination at the methyl carbon of the ethyl group, as in dihydro-3-methyl-3-(2,2,2-trifluoroethyl)-2(3H)-furanone (3), produces a compound having convulsant activity. This convulsant activity seems to be due to an increased affinity of the compound for the picrotoxin site on GABAA receptors caused by an interaction that involves the trifluoromethyl group. Results obtained with gamma-butyrolactones containing either a 3-(1-trifluoromethyl)ethyl or a 3-(1-methyl-1-trifluoromethyl)ethyl substituent indicate that the interactions of the trifluoromethyl group with the picrotoxin binding site are subject to both stereochemical and steric constraints. Sulfur for oxygen heteroatom substitution, as in the corresponding gamma-thiobutyrolactones, affects the type (competitive, non-competitive, etc.) of binding interactions that these compounds have with the picrotoxin site in a complex manner. Fluorination of alkyl groups at the C-4 and C-5 positions of gamma-butyrolactones having convulsant activity increases convulsant potency.

Rifampicin carrying polyhydroxybutyrate microspheres as a potential chemoembolization agent

In this study, we attempted to prepare microspheres from a microbial biodegradable polyester, i.e. polyhydroxybutyrate (PHB) as a potential chemoembolization agent. The drug loaded PHB microspheres were prepared by a solvent evaporation technique, in which methylene chloride, distilled water, and polyvinyl alcohol were utilized as the solvent, dispersion medium, and emulsifier, respectively. Microspheres were obtained within a size range of 5-100 microns by changing the initial polymer/solvent ratio, emulsifier concentration, stirring rate, and initial drug concentration. It was possible to obtain PHB with very narrow size distributions by applying gravity field-flow fractionation technique. Very high drug loadings of up to 407.6 mg rifampicin/g PHB were achieved. Drug release rates were very rapid. Almost 90% of the drug loaded was released in about 24 h. Both the size and drug content of PHB microspheres were found to be effective in controlling the drug release from these microspheres.

The outer surface protein A (OspA) vaccine against Lyme disease: efficacy in the rhesus monkey

The efficacy of an outer surface protein A (OspA) vaccine in three different formulations was investigated in the rhesus monkey. The challenge infection was administered using Ixodes scapularis ticks that were infected with the B31 strain of Borrelia burgdorferi. Protection was assessed against both infection and disease, by a variety of procedures. Some of the animals were radically immune suppressed, as an attempt to reveal any putative low level infection in the vaccinated animals. The significant difference found between the spirochaetal infection rates of ticks that had fed on vaccinated vs. control monkeys, lack of seroconversion in the vaccinated animals, and the absence of spirochaetal DNA in the skin of vaccinated animals in the weeks following the challenge, indicate that vaccinated monkeys were protected against tick challenge. The post-mortem immunohistochemical and polymerase chain reaction analyses, however, suggest that these monkeys may have undergone a low-level infection that was transient.

[Loss of heterozygosity on chromosome 17p13.3 in ovarian cancer and cervical cancer]

OBJECTIVE

To identify the loss of heterozygosity (LOH) on chromosome 17p13.3 in ovarian cancer and cervical cancer.

METHODS

The frequency of LOH on chromosome 17p13.3 in DNA samples from 24 ovarian cancers, 9 cervical cancers, and 13 non-malignant gynecological diseases were determined respectively, using Southern blot method with probe PYNZ. 22.

RESULTS

LOH on 17p13.3 was found in 12 of 24 (50.0%) ovarian cancers (including a borderline mucinous cystadenoma), 4 of 9 (44.4%) cervical carcinomas, and 1 of 13 (7.7%) non-malignant gynecological diseases, which was cervical intraepithelial neoplasm III (CIN III) (P < 0.01).

CONCLUSION

These results show that LOH on 17p13.3 is associated with ovarian cancer and cervical cancer, suggesting that detection of LOH on 17p13.3 may be helpful to understand the molecular pathogenesis of ovarian cancer and cervical cancer.

Babesiasis in Nanjing area, China

This article discusses the tick-borne babesiases which harm dairy cattle, buffaloes and dogs. In addition, the pathogen, vector, seasonal occurrence, hosts, symptoms, pathological changes and treatment are summarized and analysed. The pathogens in this area were identified as Babesia bigemina, B. bovis and B. gibsoni; the vectors as Boophilus microplus, Rhipicephalus haemaphysaloides, Haemaphysalis longicornis. Affected buffaloes were found from April to September, peak numbers occurred between May and July. Affected dairy cattle were most numerous in July and August. Hunting dogs were the most affected dogs. Infected dogs were found from February until the beginning of December; peak numbers occurred from September to November. Affected animals were acute cases. Symptoms and pathological changes were obvious, but jaundice was rare in dogs. Acaprin, acriflavine, imidocarb and berenil were used early and late. Their effect was ideal but resistance has developed to these drugs.

Catechol-O-methyltransferase Val158Met polymorphism: frequency analysis in Han Chinese subjects and allelic association of the low activity allele with bipolar affective disorder

Catechol-O-methyltransferase catalyses the O-methylation of biologically active or toxic catechols and is a major component of the metabolism of drugs and neurotransmitters such as L-dopa, noradrenaline, adrenaline, and dopamine. Human catechol-O-methyltransferase activity is an autosomal partially dominant trait and is strongly associated with a valine to methionine substitution at codon 158 of the protein. About 25% of Caucasians have low activity, 50% intermediate activity and 25% high activity as determined by either phenotypic or genotypic measurement. In black populations, the low activity allele (Met158; COMTL) is less frequent with about 7% being homozygous. Using a PCR based genotyping assay, we report that the Met158 allele is also less frequent in normal Han Chinese subjects with about 3% of the population being homozygous. Because of its role in catecholamine metabolism and several lines of evidence pointing to a locus for psychosis near the COMT gene on chromosome 22q11, we have analysed the COMT Val158Met polymorphism as a candidate susceptibility factor for bipolar affective disorder. We report an association between bipolar affective disorder and the Met158 allele (p = 0.004) and genotype (p = 0.01) in 93 affected Chinese subjects and 98 controls. We hypothesize that either the low activity allele of catechol-O-methyltransferase is a risk factor for bipolar affective disorder in Chinese populations or is in linkage disequilibrium with a nearby susceptibility gene or polymorphism.

[Study on prethrombotic state in patients with paroxysmal nocturnal hemoglobinuria]

OBJECTIVE

To explore the mechanism of thrombogenesis in patients with paroxysmal nocturnal hemoglobinuria (PNH).

METHODS

Thirteen parameters concerning endotheliocytes, platelets, blood coagulation, and fibrinolysis were measured in 21 PNH patients.

RESULTS

As compared with normal controls, plasma fibrin peptide A (FPA) levels were significantly higher, but antithrombin-III (AT-III) and protein C (PC) antigen levels lower in the PNH patients. Plasma tissue plasminogen activator (t-PA) activities were significantly lower while plasminogen activator inhibitor (PAI) activities markedly higher in the patients than those in the controls. The levels of the blood coagulation and fibrinolysis parameters changed more notably during the occurrence of thrombosis and hemoglobinuria episodes in the PNH patients. Platelet adhesion rates, platelet aggregation rates, beta-thromboglobulin (beta-TG), and granule membrane protein-140 (GMP-140) were within the normal ranges. Plasma vWF:Ag and endothelin-1 (ET-1) concentrations were normal in the patients as well.

CONCLUSION

Prethrombotic state is present in PNH patients, which may be caused by hypercoagulability and low fibrinolytic activity.

Molecular cloning of the gene for mouse leukotriene-C4 synthase

Leukotriene C4 (LTC4) synthase (LTC4S), an integral membrane protein, catalyzes the conjugation of leukotriene A4 with reduced glutathione to form LTC4, the biosynthetic parent of the additional cysteinyl leukotriene metabolites. An XmnI-digested fragment of a P1 clone from a 129 mouse ES library contained the full-length gene of 2.01 kb for mouse LTC4S. The mouse LTC4S gene is comprised of 5 exons of 122, 100, 71, 82 and 241 nucleotides, with intron sizes that range from 76 nucleotides to 937 nucleotides. The intron/exon boundaries are identical to those of the human genes for LTC4S and 5-lipoxygenase-activating protein (FLAP). Primer extension demonstrated a single transcription-initiation site 64 bp 5' of the ATG translation-start site. Nucleotide sequencing of 1.2 kb of the 5' flanking region revealed multiple putative sites for activating protein-2, CCAAT/enhancer-binding protein, and polyoma virus enhancer-3. Fluorescent in situ hybridization mapped the mouse LTC4S gene to mouse chromosome 11, in a region containing the genes for interleukin 13 and granulocyte/macrophage-colony-stimulating factor, and orthologous to the chromosomal location of 5q35 for the human LTC4S gene. Thus, the mouse LTC4S gene is similar in size, intron/exon organization and chromosomal localization to the human LTC4S gene. Recent mutagenic analysis of the conjugation function of human LTC4S has identified R51 and Y93 as critical for acid and base catalysis of LTA4 and reduced glutathione, respectively. A comparison across species for proteins that possess LTC4S activity reveals conservation of both of these residues, whereas R51 is absent in the FLAP molecules. Thus, within the glutathione S-transferase superfamily of genes, alignment of specific residues allows the separation of LTC4S family members from their most structurally similar counterparts, the FLAP molecules.

Association analysis of the dopamine D4 gene exon III VNTR and heroin abuse in Chinese subjects

Although social and cultural influences are clearly important, family, twin and adoption studies indicate that genes contribute significantly to substance abuse. Substance abuse is associated with novelty seeking, a heritable human personality trait which may be influenced by alleles of the dopamine D4 (DRD4) gene exon III VNTR. Consequently Kotler et al analysed the DRD4 VNTR in opiate-dependent subjects from Israel, and found a significant excess of the 7-repeat allele. We have attempted to replicate this finding using a Han Chinese case-control sample of 121 heroin-dependent subjects and 154 normal controls. We found two 7-repeat alleles which occurred exclusively in the patient group, and overall there was an excess of longer alleles, which did not reach significance (chi 2 = 7.04; P = 0.07). When the D4 VNTR was divided into 'long' (5-7 repeats) and 'short' (2-4 repeats), a significant excess of long alleles was observed in the patient group (P = 0.023, one-tailed), with an odds ratio of 2.30 (95% CI 1.07-4.93). We conclude that our findings support the hypothesis that alleles of the DRD4 exon III VNTR are susceptibility factors for heroin abuse.

Alterations of cardiac alpha 1-adrenoceptor subtypes in hypothyroid rats

1. Alterations in the cardiac alpha 1-adrenoceptor and its subtypes in hypothyroid rats were studied by radioligand binding assays and reverse transcription-polymerase chain reaction (RT-PCR). Hypothyroidism was created by feeding rats with 0.2% 2-thiouracil solution instead of daily drinking water for 20 days. 2. The density of cardiac alpha 1-adrenoceptors (Bmax) was increased from 67.5 +/- 4.3 fmol/mg in control rats to 81.1 +/- 7.2 fmol/mg (P < 0.05) in hypothyroid rats. 3. Compared with control rats, in hypothyroid rats the percentages of high-affinity sites for (+)-niguldipine and 5-methylurapidil were increased from 13.8 +/- 5.6 and 31.9 +/- 6.3%, respectively, to 24.9 +/- 7.3 and 45.5 +/- 2.4%, respectively (both P < 0.05), while those for BMY7378 were decreased from 37.2 +/- 8.9 to 23.8 +/- 8.4% (P < 0.05), respectively. The percentage of high-affinity sites for WB4101 was not significantly different in control and hypothyroid rats (43.3 +/- 9.1 and 39.4 +/- 3.6%, respectively). 4. Reverse transcription-PCR experiments revealed that the steady state levels of mRNA for alpha 1A- and alpha 1B-adrenoceptors were increased, while those for alpha 1D-adrenoceptor were decreased in the hearts of hypothyroid rats. 5. The concentration-contraction response curves for noradrenaline in the presence of a beta-adrenoceptor antagonist in control and hypothyroid rats showed that the maximal response was reduced from 344 +/- 58 to 200 +/- 23 mg, respectively (P < 0.05). 6. The data suggest that in hypothyroid rats the total number of cardiac alpha 1-adrenoceptors is increased. The change is subtype-selective, with levels of alpha 1A- and alpha 1B-adrenoceptors being increased and levels of alpha 1D-adrenoceptors being reduced. Furthermore, the positive inotropic response mediated by alpha 1-adrenoceptors is reduced in hypothyroid rats.

Site-directed mutagenesis of human leukotriene C4 synthase

The functional characteristics of leukotriene C4 synthase (LTC4S), which specifically conjugates leukotriene A4 with GSH, were assessed by mutagenic analysis. Human LTC4S and the 5-lipoxygenase-activating protein share substantial amino acid identity and predicted secondary structure. The mutation of Arg-51 of LTC4S to Thr or Ile abolishes the enzyme function, whereas the mutation of Arg-51 to His or Lys provides a fully active recombinant protein. The mutations Y59F, Y97F, Y93F, N55A, V49F, and A52S increase the Km of the recombinant microsomal enzyme for GSH. The mutation Y93F also markedly reduces enzyme function and increases the optimum for pH-dependent activity. The deletion of the third hydrophobic domain with the carboxyl terminus abolishes the enzyme activity, and function is restored by the substitution of the third hydrophobic domain and carboxyl terminus of 5-lipoxygenase-activating protein for that of LTC4S. Mutations of C56S and C82V alone or together and the deletion of Lys-2 and Asp-3 of LTC4S do not alter enzyme function. The direct linkage of two LTC4S monomers by a 12-amino acid bridge provides an active dimer, and the same bridging of inactive R51I with a wild-type monomer creates an active pseudo-dimer with function similar to that of the wild-type enzyme. These results suggest that in the catalytic function of LTC4S, Arg-51 probably opens the epoxide ring and Tyr-93 provides the thiolate anion of GSH. Furthermore, the monomer has independent conjugation activity, and dimerization of LTC4S maintains the proper protein structure.

[Biopsy of labial salivary glands and lacrimal glands in the diagnosis of Sjögren's syndrome]

OBJECTIVES

To determine the diagnostic value for Sjögren's syndrome (SS) by evaluating the presence of focal adenitis in labial salivary gland (LSG) and lacrimal gland (LG) biopsy specimens.

METHODS

109 suspected cases with SS underwent the biopsies. The diagnostic criteria of Fox et al. were followed. Both Chisholm-Manson's grading standard and Greenspan's focus score were used for the evaluation.

RESULTS

Myoepithelial islands and severe lymphocyte infiltration with germinal centers were observed only in LG biopsy specimens. The lymphocytic foci scored of LG were significantly higher than that of LSG in 23 cases having both biopsy results. The evaluation of both kinds of specimen for such a patient was significantly more effective in diagnosing SS than using either one of them alone.

CONCLUSION

We recommend that both LSG and LG biopsies be performed in patients suspected of having SS to reduce false negative results and improve diagnostic accuracy.

[Study on transposition behavior of IS5376 in Bacillus stearothermophilus]

IS5376 and IS5377 are two transposable elements discovered in Bacillus stearothermophilus. Analysis of random samples revealed that the frequency of transposition of IS5376 from CU21 chromosome to plasmids pFDC5 and pFDC12 was much higher at 65 degrees C than that at 48 degrees C while that of IS5377 was very low at both 48 degrees C and 65 degrees C. The exact nature of the temperature effect is obscure at present from evidences obtained so far it is concluded that this is a consequence of the innate property of IS5376. Furthermore, it was found that a certain degree of site specificity in transposition was evident and that a direct repeat of 4 or 5 bp of the target DNA appeared at the site of transposition.

Alterations of cardiac and lymphocyte beta- adrenoceptors in rat with chronic heart failure

The alterations of cardiac and lymphocyte beta-adrenoceptors were observed in the rats with chronic heart failure produced by constriction of both abdominal aorta and renal artery. The results showed that beta(1)-adrenoceptor density and mRNA levels were increased, whereas these levels remained unchanged for beta(2). The concentrationcontractile response curve for isoproterenol was shifted m the right in cardiac atrium, whereas the concentration-CAMP accumulation response curve for isoproterenol in myocardium was not changed. The number of beta-adrenoceptom in blood lymphocyte was markedly reduced. Thus in the heart-failure rats the density of cardiac beta-adrenoceptor was increased accompanying reduced beta-adrenoceptormediated positive inotropic response, suggesting a post adenylate cyclase dysfunction or impaired contractile components. In contrast, the alteration of beta-adrenoceptor in lymphocyte is consistent with the reduced beta-adrenoceptor-mediated inotropic response in heart.

[A study on polycyclic aromatic hydrocarbon-DNA adduct in lung cancer patients exposed to indoor coal-burning smoke]

The objective of this study is to explore the etiology and early risk evaluation of lung cancer in Xuanwei County, Yunnan Province of China. Polycyclic aromatic hydrocarbon (PAH)-DNA adduct in brushing cells from fibrobronchoscopy was determined in 30 cases with lung cancer in Xuanwei County and 10 controls in Kunming, Yunnan Province by 32P-postlabelling assay. Results showed that PAH-DNA levels in lung cancer patients of Xuanwei County were much more higher than those in controls. It suggested that air pollution caused by indoor coal-burning associated directly with the occurrence of lung cancer, and detection of DNA adduct could be used as an indicator for its risk assessment in population.

Partial splenic embolization for hypersplenism concomitant with or after arterial embolization of hepatocellular carcinoma in 30 patients

PURPOSE

To study the value of partial splenic embolization (PSE) for the treatment of hypersplenism in patients undergoing embolization of hepatocellular carcinoma (HCC).

METHODS

Transcatheter hepatic arterial embolization (THAE) combined with PSE was performed in 30 patients with HCC complicating liver cirrhosis, portal hypertension, and hypersplenism. Gelfoam sponge was used as the embolic material for PSE and limited to 100-150 pieces.

RESULTS

More than 50% of splenic parenchyma was infarcted in 27 patients. Leukopenia and thrombocytopenia were corrected by PSE in 25 of 27 patients with hypersplenism. In 26 patients with esophageal varices, including 5 patients with bleeding, no rebleeding occurred during a 6-17 month follow-up. Hypersplenism was not corrected in 2 of 3 patients whose infarcted splenic parenchyma was less than 50%. No splenic abscesses or other severe complications were observed. Of the 30 patients treated, 19 are still alive after 1 year.

CONCLUSIONS

THAE combined with PSE is a safe and effective measure for patients with HCC.

Superior real-time holographic storage properties in doped potassium sodium strontium barium niobate crystal

We demonstrate superior holographic storage performance in a cobalt doped potassium sodium strontium barium niobate (Co:KNSBN) crystal that possesses a fast response time of 1.4 ms, a large photorefractive sensitivity of 13 x 10(-3) cm(3) J(-1) under a total writing intensity of 1 W/cm(2) , and high spatial resolution of 45 line pairs/mm. Reconstructed images with high fidelity have been obtained in real-time holographic storage. The dynamic properties of the index grating, the dependence of response time on writing intensity, and the dark decay of diffraction signal with increased writing intensity indicate that two species and shallow traps exist in Co:KNSBN crystal.

Expression of the retinoblastoma (RB) tumor suppressor gene inhibits tumor cell invasion in vitro

To determine if replacement of the retinoblastoma (RB) tumor suppressor gene could inhibit invasion of RB-defective tumor cells, the capacity of tumor cells to migrate or invade was quantitated by the Boyden chamber assay. The studies were done in a diverse group of stable RB-reconstituted human tumor cell lines, including those derived from the osteosarcoma and carcinomas of the lung, breast and bladder. The expression of the exogenous wild-type RB protein in these tumor cell lines was driven by either a constitutively active promoter or an inducible promoter. It was found that significantly more tumor cells from the parental RB-defective cell lines and the RB revertants than from the RB-reconstituted RB+ cell lines penetrated through the Matrigel (P<0.001, two-tailed t-test), although both RB+ and RB- cells migrated at approximately the same rate on uncoated polycarbonate filters in the Boyden chambers. Of note, the inhibition of invasiveness of various RB-defective tumor cells by RB replacement was apparently well correlated with suppression of their tumorigenicity in vivo. In contrast, although either functional RB or p53 re-expression effectively suppressed tumor formation in nude mice of the RB-/p53null osteosarcoma cell line, Saos-2, replacement of the wild-type p53 gene had much less impact on their invasiveness as compared to the RB gene. These studies provided an insight into the broader biological basis of the RB-mediated tumor suppression in RB-defective tumor cells.

Ascaris, people and pigs in a rural community of Jiangxi Province, China

A longitudinal investigation on natural populations of Ascaris in humans and pigs and an investigation of soil contamination with Ascaris eggs were carried out from June 1993 to June 1994 in 2 villages, Manhu area, Xinjian County, Jiangxi Province, China. Results from these studies indicate that although human ascariasis is endemic there is significant fluctuation in both prevalence and the mean number of eggs/g faeces (epg) of the communities. Fluctuation of age-stratified prevalence and mean epg was detected in children but not in most adult groups. Most cases of human ascariasis were judged to involve low intensities of infection and a typical overdispersion distribution pattern was observed through the year. It was estimated that during the year, nearly half of the eggs discharged in the environment came from infections in children aged between 2 and 15 years which accounted for about 30% of the total population. Soil in and around houses and in vegetable gardens was found to be contaminated by Ascaris eggs and this situation remained relatively stable throughout the year. Monthly developmental rate of Ascaris eggs in soil was detected and the results suggest that the fluctuation in prevalence observed during the year should be directly attributed to the effect of seasonality of egg development. Features of Ascaris infection in pigs were found to be similar to those in humans except for a lower mean intensity of infection. The possibility of cross-infection of Ascaris between human and pig hosts is discussed.

Quantification of mRNAs for three alpha 1-adrenoceptor subtypes in rat aorta by solution hybridization

We used solution hybridization to quantify mRNAs for alpha 1A-, alpha 1B-and alpha 1D-adrenoceptor(AR) in rat aortae. The results showed that the mRNA for alpha 1A-, alpha 1B- and alpha 1D-AR was 0.28 +/- 0.03 fmol, 0.35 +/- 0.03 fmol and 0.82 +/- 0.09 fmol, respectively, in 40 micrograms total RNA extracted from rat aorta. The dominant expression of alpha 1D-AR further support the recent findings that alpha 1D-AR is a major functional receptor subtype of AR in rat aorta.

Retrovirus-mediated wild-type p53 gene transfer to tumors of patients with lung cancer

A retroviral vector containing the wild-type p53 gene under control of a beta-actin promoter was produced to mediate transfer of wild-type p53 into human non-small cell lung cancers by direct injection. Nine patients whose conventional treatments failed were entered into the study. No clinically significant vector-related toxic effects were noted up to five months after treatment. In situ hybridization and DNA polymerase chain reaction showed vector-p53 sequences in posttreatment biopsies. Apoptosis (programmed cell death) was more frequent in posttreatment biopsies than in pretreatment biopsies. Tumor regression was noted in three patients, and tumor growth stabilized in three other patients.

[Quantitative determination of ginsenoside Rg1 in Capsulae gansuning by TLC-scanning]

The ginsenoside Rg1 in Capsulae Gansuning was quantitatively determined by TLC-scanning. The sample was pretreated with a chemical method featuring simplicity and efficacy. The average recovery of ginsenoside Rg1 is 97.95%, RSD = 1.85% (n = 5).

Artificial neural network to assist psychiatric diagnosis

BACKGROUND

Artificial Neural Network (ANN), as a potential powerful classifier, was explored to assist psychiatric diagnosis of the Composite International Diagnostic Interview (CIDI).

METHOD

Both Back-Propagation (BP) and Kohonen networks were developed to fit psychiatric diagnosis and programmed (using 60 cases) to classify neurosis, schizophrenia and normal people. The programmed networks were cross-tested using another 222 cases. All subjects were randomly selected from two mental hospitals in Beijing.

RESULTS

Compared to ICD-10 diagnosis by psychiatrists, the overall kappa of BP network was 0.94 and that of Kohonen was 0.88 (both P < 0.01). In classifying patients who were difficult to diagnose, the kappa of BP was 0.69 (P < 0.01). ANN-assisted CIDI was compared with expert system assisted CIDI (kappa = 0.72-0.76); ANN was more powerful than a traditional expert system.

CONCLUSION

ANN might be used to improve psychiatric diagnosis.

Identification, sequence, and expression of the gene encoding gamma-glutamyltranspeptidase in Bacillus subtilis

The Bacillus subtilis gene encoding gamma-glutamyltranspeptidase (GGT) activity encodes a protein of 587 amino acids having extensive homologies with other procaryotic GGTs. Inactivation of the gene abolished all measurable GGT activity, which in the wild type was found mainly to be excreted into the medium commencing at the end of vegetative growth.

Molecular cloning, expression and characterization of mouse leukotriene C4 synthase

Leukotriene C4 synthase (EC 2.5.1.37) catalyzes the conjugation of reduced glutathione (GSH) with leukotriene A4 to form the intracellular parent of the proinflammatory cysteinyl leukotrienes. Human leukotriene C4 synthase shares substantial amino acid identity in its consensus N-terminal two-thirds with 5-lipoxygenase-activating protein and has a region (residues 37-58) that exhibits 46% amino acid identity with a domain of this protein (residues 41 -62) to which an inhibitor binds. We have now cloned mouse leukotriene C4 synthase CDNA using the polymerase chain reaction to screen a mouse pcDNA3 expression library with oligonucleotide primers based on the translated human leukotriene C4 synthase cDNA sequence. Mouse leukotriene C4 synthase cDNA is 667 bp in length, including the poly(A)-rich tail, and shows 87% similarity with the human cDNA within the open reading frame. The deduced 150-amino-acid sequence of mouse leukotriene C4 synthase (differs from the human enzyme by only 18 amino acids, of which 9 reside at the C terminus. The potential N-glycosylation site, two protein kinase C phosphorylation sites, the two cysteine residues, and the putative inhibitor-binding domain (substitutions Thr4l-->Ser and Tyr50-->Phe) were conserved in mouse leukotriene C4 synthase. Northern blot analysis indicated that the leukotriene C4 synthase RNA transcript is widely distributed. The Km values for leukotriene A4 methyl ester, leukotriene A4 free acid and GSH were 7.6 microM, 3.6 microM and 1.6 mM, respectively, for purified human recombinant enzyme, and 10.3 microM, 2.5 microM and 1.9 microM, respectively, for purified recombinant mouse enzyme; the corresponding Vmax values were 2.5, 1.3 and 2.7 micromol x min(-1) x mg(-1) protein, respectively, for human enzyme, and 2.3, 1.2 and 2.2 micromol x min(-1) x mg(-1) protein, respectively, for mouse enzyme. The 5-lipoxygenase-activating-protein inhibitor, MK-886, was active against both human and mouse recombinant leukotriene C4 synthase with IC50 values of 3.1 microM and 2.7 microM respectively. These findings confirm that the leukotriene C4 synthases belong to a gene family that includes the 5-lypoxygenase-activating protein and suggest that the C-terminal domain of leukotriene C4 synthase may not be critical for its conjugation function.