The relationship and diagnostic efficacy of N-terminal propeptide type III collagen in pathological changes associated with non-alcoholic steatohepatitis

OBJECTIVE

This study delves into the role of N-terminal propeptide type III collagen (PIIINP) in the diagnosis and management of liver pathological changes associated with non-alcoholic steatohepatitis (NASH).

PATIENTS AND METHODS

We collected baseline information, pathological data, and serum PIIINP levels of 168 patients diagnosed with non-alcoholic fatty liver disease (NAFLD) via ultrasound imaging in our hospital. Based on the non-alcoholic fatty liver disease activity score (NAS), patients with different NAFLD patterns were divided into a Definite NASH group and a Not/borderline group. Differences in PIIINP levels and pathological features between the two groups were compared and analyzed. The diagnostic value of PIIINP for NASH was evaluated using the receiver operating characteristic (ROC) curve.

RESULTS

Patients with NASH exhibited significantly higher values of homeostatic model assessment for insulin resistance (HOMA-IR), fibrosis biomarker fibrosis-4 (FIB-4), aminotransferase-to-platelet ratio index (APRI), and serum PIIINP levels than those classified as Not/borderline. A marked increase in the serum concentrations of PIIINP was observed with the severity of fatty degeneration, lobular inflammation, and hepatocellular ballooning. The AUC of PIIINP for diagnosing definite NASH was 0.766 (95% CI: 0.694, 0.839), APRI was 0.634 (95% CI: 0.549, 0.718), and FIB-4 was 0.621 (95% CI: 0.534, 0.708). The AUC of PIIINP for diagnosing definite NASH was significantly higher than that of APRI and FIB-4 (all p<0.05). Utilizing the predetermined threshold values for diagnostic parameters, the PIIINP measure demonstrated a sensitivity of 71.6% and a specificity of 73.6% in diagnosing definitive NASH when its value exceeded 7.72 ng/dL. This yielded a Youden index of 0.45. Similarly, when the APRI measure exceeded 0.21, it exhibited a sensitivity of 60.5% and a specificity of 63.2%, resulting in a Youden index of 0.24. Moreover, when the FIB-4 index surpassed 0.26, it showed a sensitivity of 46.9% and a specificity of 79.3%, culminating in a Youden index of 0.26.

CONCLUSIONS

NASH patients in this study exhibited significantly elevated PIIINP serum levels, which were closely associated with hepatocyte pathological changes. PIIINP demonstrated superior competence in diagnosing NASH than APRI and FIB-4 and thus offers a viable alternative for the clinical diagnosis of NASH.

Probing ^{93m}Mo Isomer Depletion with an Isomer Beam

The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC). However, the measured excitation probability of 1.0(3)% is far beyond the theoretical expectation. In order to understand the inconsistency between theory and experiment, we produce the ^{93m}Mo nuclei using the ^{12}C(^{86}Kr,5n) reaction at a beam energy of 559 MeV and transport the reaction residues to a detection station far away from the target area employing a secondary beam line. The isomer depletion is expected to occur during the slowdown process of the ions in the stopping material. In such a low γ-ray background environment, the signature of isomer depletion is not observed, and an upper limit of 2×10^{-5} is estimated for the excitation probability. This is consistent with the theoretical expectation. Our findings shed doubt on the previously reported NEEC phenomenon and highlight the necessity and feasibility of further experimental investigations for reexamining the isomer depletion under low γ-ray background.

[Influential factors related to osteoradionecrosis of the mandible in oral and maxillofacial cancer patients following radiotherapy]

Objective: To identify risk factors associated with mandibular osteoradionecrosis (ORN) in oral and maxillofacial cancer patients following radiotherapty and to provide scientific basis for the etiological research and clinical prevention of mandibular ORN. Methods: A retrospective study was conducted in patients with oral and maxillofacial-head and neck cancer during the period from January 2013 to December 2015. Influential factors related to mandibular ORN were screened by single factor analysis, Lasso and Logistic regression analysis. Results: A total of 757 patients were analyzed, and the total incidence of mandibular ORN was 12.0%(91/757). There were 443 males and 314 females, aged (51.8±13.7) years. Thirty-five related factors were screened to 28 by single factor analysis. It was determined by Lasso regression analysis that, radiation doses (OR=1.135, P=0.034, 95%CI: 1.089-1.232), T classification (OR=2.586, P=0.001, 95%CI: 1.482-4.512), mandibular surgery (OR=9.101, P<0.001, 95%CI: 2.796-29.630), periodontitis (OR=6.089, P<0.001, 95%CI: 2.708-13.693), diabetes (OR=4.467, P=0.002, 95%CI: 1.705-11.704), tooth extraction after radiotherapy (OR=3.228, P=0.001, 95%CI: 1.640-6.350), dental caries (OR=2.911, P=0.009, 95%CI: 1.300-6.516), periapical periodontitis (OR=2.726, P=0.016, 95%CI: 1.209-6.145), smoking (OR=4.438, P=0.002, 95%CI: 1.702-11.571) and unilateral/bilateral radiotherapy (OR=2.225, P=0.028, 95%CI: 1.090-4.545) were significantly associated with developing mandibular ORN. Conclusions: Ten main risk factors for mandibular ORN were identified through the single center, large sample, retrospective analysis, which has a certain value for clinical prevention of mandibular ORN. Prospective, randomized controlled trials and long-term follow-up are still needed.

Large Isospin Asymmetry in ^{22}Si/^{22}O Mirror Gamow-Teller Transitions Reveals the Halo Structure of ^{22}Al

β-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of β-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror β decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

Silencing of miR-330-5p stimulates osteogenesis in bone marrow mesenchymal stem cells and inhibits bone loss in osteoporosis by activating Bgn-mediated BMP/Smad pathway

OBJECTIVE

To illustrate the role of micro ribonucleic acid (miR)-330-5p in regulating osteogenesis through biglycan (Bgn)-mediated bone morphogenetic protein (BMP)/Smad pathway.

MATERIALS AND METHODS

A mouse model of osteoporosis (OP) was established by ovariectomy (OVX). BMD and miR-330-5p levels in mice undergoing sham operation or OVX were determined. BMD and BV/TV in OP mice with in vivo knockdown of miR-330-5p were measured by Micro-CT. After silencing of miR-330-5p in mouse primary bone marrow stromal cells (BMSCs), expression changes in osteogenesis-associated genes, ALP activity, and mineralization ability were assessed. Subsequently, the interaction between miR-330-5p and Bgn was examined by Dual-Luciferase reporter gene assay and Western blotting. Then, Bgn levels in BMSCs undergoing osteogenesis at different time points were measured. At last, the regulatory effects of miR-330-5p/Bgn axis on the BMP/Smad pathway, ALP activity, and mineralization ability in BMSCs were evaluated.

RESULTS

BMD was decreased and miR-330-5p was upregulated in OP mice. OP mice with in vivo knockdown of miNA-330-5p presented higher BMD and BV/TV than controls. Transfection with miR-330-5p inhibitor upregulated osteogenesis-associated genes, ALP activity, and mineralization ability in BMSCs. Bgn was time-dependently upregulated in BMSCs undergoing osteogenesis, which was indicated to be the target gene of miR-330-5p. Besides, Bgn level was negatively regulated by miR-330-5p. Importantly, Bgn was able to reverse the regulatory effects of miR-330-5p on the BMP/Smad pathway, ALP activity, and mineralization ability in BMSCs.

CONCLUSIONS

Knockdown of miR-330-5p facilitates osteogenesis in BMSCs through the Bgn-induced BMP/Smad pathway, thus alleviating the progression of OP.

[Construction and analysis of competitive endogenous RNA regulatory network related to gastric cancer]

Objective: To construct the competitive endogenous RNA (ceRNA) network related to gastric cancer and explore the molecular mechanism. Methods: The expression profiles of lncRNA, miRNA and mRNA in gastric cancer and paracancer tissues were analyzed by biochip technology, edgeR package in R software was used to filtrate differential expression genes (multiple change of >1.5 times, P<0.05) and volcano map was drawn. Based on the online miRNA-lncRNA prediction tool lncBase database and the miRNA Target gene prediction database (miRTarBase, target-scan, miRDB, starBase), the relationship between miRNA, lncRNA and mRNA was predicted. Cytoscape software was used to construct lncRNA-miRNA-mRNA ceRNA network and key genes (hub genes) were identified based on cytohubba calculation of degree score of each node. Then Hub genes related to the prognosis of gastric cancer were verified in the TCGA database. The GO and KEGG enrichment analysis of differentially expressed mRNA was performed using the online biological information annotation database DAVID, P<0.05 and false discovery rate (FDR)<0.05 were used as cut-off criteria. R software was used to download the RNA sequencing data and mirna-seq data of gastric cancer and adjacent tissues in TCGA database, edgeR package was used to screen out differentially expressed mRNA, miRNA and lncRNA, and some differentially expressed genes in our data were verified. In OncoLnc database, STAD project of TCGA data was selected and hub gene was input. Patients were divided into two groups based on the median value for hub genes and Kaplan-meier analysis was performed. Results: The differentially expressed 766 mRNA, 110 lncRNA and 10 miRNA were screened out, among them 90 mRNA, 4 lncRNA and 6 miRNA were used to construct the ceRNA network, and 2 of the 20 hub genes were related to the prognosis of patients. MLK7-AS1, SPP1, SULF1, hsa-miR-1307-3p were upregulated in gastric cancer tissues from our biochip, while MT2A, MT1X were downregulated, which were consistent with the results of TCGA gastric cancer database. The differentially expressed mRNAs were significantly enriched in the biological process (BP) and the mineral absorption pathway. CHST1 was negatively correlated while miR-183-5p was positively corelated with the survival of patients. Conclusion: The establishment of ceRNA network for gastric cancer is conducive to further understanding of the molecular biological mechanism. CHST1 and miR-183-5p can be used as prognostic factors of gastric cancer.

[Trend in proportion and clinicopathological characteristics of young women with stage Ⅰa2 to Ⅱa2 cervical cancer]

Objective: To analyze the 13 years trend in proportion, risks factors and clinicopathological characteristics of young women with stage Ⅰa2 to Ⅱa2 cervical cancer by using multi-center data of cervical cancer in China. Methods: The clinicopathological data of 46 313 patients with cervical cancer treated from 37 hospitals in China were obtained from January 2004 to December 2016. Using clinical and pathologic data, each patient's stage was reclassified by the 2018 International Federation of Gynecology and Obstetrics (FIGO) staging system. A total of 19 041 patients were selected according to the following criteria: FIGO stage Ⅰa2 to Ⅱa2, underwent type B or C radical hysterectomy and pelvic lymphadenectomy. All the patients were divided into two groups: the study group of 1 888 patients aged 35 years or younger and the control group of 17 153 patients aged over 35 years. The 13 years trend in proportion of young women with stage Ⅰa2 to Ⅱa2 cervical cancer, risks factors and clinicopathological characteristics of two groups were retrospectively analyzed. Results: (1) The total number of hospitalized patients with stage Ⅰa2 to Ⅱa2 cervical cancer increased annually. However, a downward trend of patients aged 35 years or younger was observed (P<0.01) . The constituent ratio of patients aged 35 years or younger was significantly greater during 2004-2010 than that during 2011-2016 [12.6% (820/6 484) and 8.5% (1 068/12 557) , respectively; χ(2)=82.101, P<0.01]. (2) Compared with patients aged over 35 years, patients aged 35 years or younger had an earlier age at menarche, a later age at marriage, lesser gravida and parity (all P<0.01). The positive rate of high-risk HPV infection was not statistically different between two groups (all P>0.05). (3) The proportions of stage Ⅰ, exophytic type and non-squamous histological type in patients aged 35 years or younger were clearly higher than those in patients aged over 35 years (83.4% vs 68.5%, P<0.01; 63.2% vs 56.2%, P<0.01; 13.9% vs 12.0%, P<0.05, respectively). Whereas the poor differentiation ratios of the two groups had no statistical significance (P>0.05). (4) As for the postoperative pathological risk factors, the rate of surgical margin involvement in patients aged 35 years or younger was lower than that aged over 35 years (1.1% vs 1.8%, P<0.05), and the rate of depth of stromal invasion >1/2 in patients aged 35 years or younger was lower than that in patients aged over 35 years (40.1% vs 50.9%, P<0.01). In addition, there were no significant difference in parametrial margin involvement, tumor size and lymph vascular space invasion between two groups (all P>0.05). Conclusions: The trend in proportion among hospitalized patients for stage Ⅰa2 to Ⅱa2 cervical cancer in young women is decreasing yearly. Compared with cervical cancer in middle-aged and elderly women, cervical cancer in young women have an earlier age at menarche, a higher proportion of stage Ⅰ patients and non-squamous histological type. In terms of the postoperative pathological risk factors, the rate of surgical margin involvement and depth of stromal invasion >1/2 in young women with cervical cancer are lower than in middle-aged and elderly women.

[The influence of Thymidine Phosphorylase genetic variation on clinical outcomes and safety of colorectal cancer patients received adjuvant chemotherapy after R0 resection]

Objective: To study the association between Thymidine Phosphorylase (TYMP) genetic variation and clinical outcomes and safety of postoperative colorectal cancer (CRC) patients. Methods: A total of 235 patients with colorectal cancer underwent surgical treatment were included in this retrospective analysis. Peripheral blood and the postoperative tissue specimen of the CRC patients were collected for the genotyping of polymorphism and TYMP mRNA expression, respectively. The correlation between polymorphism and clinical outcomes and safety of postoperative CRC patients were analysed. Results: Located in the upstream, 5633C>T was of clinical significance. The prevalence of 5633C>T in TYMP among the CRC patients were as follows: CC genotype 149 cases (63.40%), CT genotype 73 cases (31.06%), TT genotype 13 cases (5.54%), minor allele frequency of 5633C>T is 0.21. The distribution of three genotypes was in accordance with Hardy-Weinberg Equilibrium (P=0.313). CT genotype and TT genotype patients were merged in the comparison of prognosis. The survival analysis of patients with different genotypes found that the median Overall Survival (OS) of CT/TT genotype and CC genotype were 5.8 and 4.5 year, which was statistically significant (P=0.009). Adjusted in multivariate Cox regression analysis, CT/TT genotype was an independent favorable factor for OS (HR=0.67, P=0.015). Additionally, of the 87 postoperative tissue specimens, the results showed that the expression of TYMP in cancer tissues of the patients with CT or TT genotypes were significantly higher than those of the wild type CC genotype patients (P=0.019). And the safety analysis showed that the incidence of grade 3 hand-foot syndrome among CT/TT genotype patients were higher than that of CC genotype patients (33.72% vs 20.13%, OR=1.68, P=0.021). Conclusion: The polymorphism 5633C>T of TYMP may impact the prognosis of CRC patients received adjuvant chemotherapy by influencing the mRNA expression of TYMP.

Effects of dietary fiber on growth performance, slaughter performance, serum biochemical parameters, and nutrient utilization in geese

We investigated the effects of dietary fiber on growth performance, slaughter performance, serum biochemical parameters, and nutrient utilization in geese. A total of 468 one-day-old healthy male Yangzhou goslings with similar body weight were randomly divided into 3 groups with 6 replicates per group and 26 geese per replicate. The geese were then raised for 70 days on diets with a dietary fiber level of 2.5% (Group I), 6.1% (Group III), or 4.3% for d one to 28 and 6.1% for d 29 to 70 (Group II). The geese in Groups II and III had higher body weight, higher average daily gain, and lower ratio of feed to gain compared with those in Group I (P < 0.05 for each comparison). The geese in Groups II and III had greater body-size measurements (half-diving length, body length, keel length, and shank circumference), heavier viscera (heart, gizzard, proventriculus, duodenum, jejunum, ileum, and cecum), greater slaughter yield (semi-eviscerated carcass yield, eviscerated carcass yield, and breast yield), lower serum levels of alanine transaminase, uric acid, and blood urea nitrogen, and higher serum levels of glucose and high-density lipoprotein compared with those in Group I (P < 0.05 for each comparison). The geese in Groups II and III exhibited greater utilization of energy and crude protein compared with those in Group I (P < 0.05). Taken together, the results suggest that the low-fiber diet had negative effects on growth performance, slaughter performance, serum biochemical parameters, and nutrient utilization. As herbivorous poultry, geese depend on dietary fiber for normal performance. Dietary fiber is thus an essential nutrient for geese.

Observation of enhanced monopole strength and clustering in (12)Be

In a recent breakup-reaction experiment using a Be12 beam at 29  MeV/nucleon, the 0+ band head of the expected He4+He8 molecular rotation was clearly identified at about 10.3 MeV, from which a large monopole matrix element of 7.0±1.0  fm2 and a large cluster-decay width were determined for the first time. These findings support the picture of strong clustering in Be12, which has been a subject of intense investigations over the past decade. The results were obtained thanks to a specially arranged detection system around zero degrees, which is essential in determining the newly emphasized monopole strengths to signal the cluster formation in a nucleus.

Virulence Characterization of International Collections of the Wheat Stripe Rust Pathogen, Puccinia striiformis f. sp. tritici

Wheat stripe rust (yellow rust [Yr]), caused by Puccinia striiformis f. sp. tritici, is an economically important disease of wheat worldwide. Virulence information on P. striiformis f. sp. tritici populations is important to implement effective disease control with resistant cultivars. In total, 235 P. striiformis f. sp. tritici isolates from Algeria, Australia, Canada, Chile, China, Hungary, Kenya, Nepal, Pakistan, Russia, Spain, Turkey, and Uzbekistan were tested on 20 single Yr-gene lines and the 20 wheat genotypes that are used to differentiate P. striiformis f. sp. tritici races in the United States. The 235 isolates were identified as 129 virulence patterns on the single-gene lines and 169 virulence patterns on the U.S. differentials. Virulences to YrA, Yr2, Yr6, Yr7, Yr8, Yr9, Yr17, Yr25, YrUkn, Yr28, Yr31, YrExp2, Lemhi (Yr21), Paha (YrPa1, YrPa2, YrPa3), Druchamp (Yr3a, YrD, YrDru), Produra (YrPr1, YrPr2), Stephens (Yr3a, YrS, YrSte), Lee (Yr7, Yr22, Yr23), Fielder (Yr6, Yr20), Tyee (YrTye), Tres (YrTr1, YrTr2), Express (YrExp1, YrExp2), Clement (Yr9, YrCle), and Compair (Yr8, Yr19) were detected in all countries. At least 80% of the isolates were virulent on YrA, Yr2, Yr6, Yr7, Yr8, Yr17, YrUkn, Yr31, YrExp2, Yr21, Stephens (Yr3a, YrS, YrSte), Lee (Yr7, Yr22, Yr23), and Fielder (Yr6, Yr20). Virulences to Yr1, Yr9, Yr25, Yr27, Yr28, Heines VII (Yr2, YrHVII), Paha (YrPa1, YrPa2, YrPa3), Druchamp (Yr3a, YrD, YrDru), Produra (YrPr1, YrPr2), Yamhill (Yr2, Yr4a, YrYam), Tyee (YrTye), Tres (YrTr1, YrTr2), Hyak (Yr17, YrTye), Express (YrExp1, YrExp2), Clement (Yr9, YrCle), and Compair (Yr8, Yr19) were moderately frequent (>20 to <80%). Virulence to Yr10, Yr24, Yr32, YrSP, and Moro (Yr10, YrMor) was low (≤20%). Virulence to Moro was absent in Algeria, Australia, Canada, Kenya, Russia, Spain, Turkey, and China, but 5% of the Chinese isolates were virulent to Yr10. None of the isolates from Algeria, Canada, China, Kenya, Russia, and Spain was virulent to Yr24; none of the isolates from Algeria, Australia, Canada, Nepal, Russia, and Spain was virulent to Yr32; none of the isolates from Australia, Canada, Chile, Hungary, Kenya, Kenya, Nepal, Pakistan, Russia, and Spain was virulent to YrSP; and none of the isolates from any country was virulent to Yr5 and Yr15. Although the frequencies of virulence factors were different, most of the P. striiformis f. sp. tritici isolates from these countries shared common virulence factors. The virulences and their frequencies and distributions should be useful in breeding stripe-rust-resistant wheat cultivars and understanding the pathogen migration and evolution.

Direct mass measurements of short-lived A=2Z-1 nuclides (63)Ge, (65)As, (67)Se, and (71)Kr and their impact on nucleosynthesis in the rp process

Mass excesses of short-lived A=2Z-1 nuclei (63)Ge, (65)As, (67)Se, and (71)Kr have been directly measured to be -46,921(37), -46,937(85), -46,580(67), and -46,320(141)  keV, respectively. The deduced proton separation energy of -90(85)  keV for (65)As shows that this nucleus is only slightly proton unbound. X-ray burst model calculations with the new mass excess of (65)As suggest that the majority of the reaction flow passes through (64)Ge via proton capture, indicating that (64)Ge is not a significant rp-process waiting point.

Race Dynamics, Diversity, and Virulence Evolution in Puccinia striiformis f. sp. tritici, the Causal Agent of Wheat Stripe Rust in China from 2003 to 2007

Stripe (or yellow) rust caused by Puccinia striiformis f. sp. tritici is the most destructive foliar disease of wheat in China. The pathogen populations were analyzed for virulence evolution, complexity, phenotypic dynamics, and diversity on temporal and spatial bases. A total of 41 races were identified and characterized from 4,714 stripe rust isolates collected during 2003 through 2007 from wheat growing areas in 15 provinces in China. The races were based on avirulence/virulence patterns to 19 differential host genotypes. Chinese stripe rust population exhibited high diversity with a complex virulence structure. Comparisons using the relative Shannon's index indicated that some differences in the richness and evenness of races were present in pathogen populations within years and between regions despite a national tendency to reduced diversity over time. A noticeably increased frequency of race CYR33 (Chinese yellow rust 33) with virulence for YrSu was the major virulence change recorded in this study compared to the results on an annual basis. Isolates of Puccinia striiformis f. sp. tritici from different regions showed differences in the composition of races, distribution frequency, and diversity. The uneven distribution of major races and comparatively greater diversity in the Northwest and Southwest regions than that in the Huang-Huai-Hai region suggest that long-distance migrations of the pathogen occur from one or more over-summering areas eastward into over-wintering areas. This supports the hypothesis that southern Gansu and northwestern Sichuan comprises a "center of origin for virulence". Mutation of virulence or avirulence for host resistance in the stripe rust fungus may be the basic cause of the occurrence of new virulent types. The subsequent dominance of certain races will vary with parasitic fitness and the opportunities to be selected through large-scale cultivation of varieties with matching resistance genes. Implications of the center of origin for virulence variation and diversity in the pathogen population and an alternative strategy for limiting virulence evolution are discussed.

Photoprotection by tocopherol submicron emulsion against UV-mediated damage in HaCaT cells

alpha-Tocopherol is a lipophilic vitamin E that shows antioxidative, antiaging and antiphotodamage activity. Nanometer biotechnology is more widely used in the entrainment system of drug carriers and the development for new pharmaceutical preparations. Ultraviolet irradiation to human skin in the long term can result in photoaging and photocarcinogenesis. The purpose of this study was to observe the biological features of tocopherol submicron emulsion (vitE SME) and to clarify the roles of vitE SME on UVB-induced photodamage in HaCaT keratinocytes (KC). VitE SME was prepared by high-pressure homogenization and microemulsion technique. HaCaT KC was incubated in the culture medium supplied with 1/200 and 1/400 of VitE SME prior to different dosages of UVB irradiation. The vitamin E amount in the culture medium was measured by high-performance liquid chromatography (HPLC). Cell growth and cellular viability was detected by MTT assay. The amount of vitamin E remaining in the culture medium significantly decreased during the first 8 h, and less than 10% can be detected by the terminal experiment (24 h). No cytotoxicity effect of tocopherol NM on HaCat KC was observed. In contrast to the control group, the cellular viability of VitE SME-treated group increased 44.22% by 24 h. Compared with irradiated groups without VitE SME, cell proliferation decreased by 17.77% and 40.42% when the HaCaT KC was irradiated with 30 mJ/cm(2) and 90 mJ/cm(2) UVB irradiation, respectively. VitE SME has no toxicity to cell culture system and is characterized by stable release and penetration. Pre-incubation with VitE SME can partly reduce UV-induced cell damage, and the photoprotective efficiency to UVB irradiation also shows time dependence.

Antidepressant-like profile and reduced sensitivity to rolipram in mice deficient in the PDE4D phosphodiesterase enzyme

Pharmacological inhibition of type 4 cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase (PDE4) produces antidepressant-like effects in animals; however, it is not known which of the four PDE4 subtypes mediates these actions. In the present study, immunoblot analysis showed loss of phosphodiesterase 4D (PDE4D) expression in the cerebral cortex and hippocampus of PDE4D knockout (PDE4D-/-) mice, but unchanged PDE4A and PDE4B expression, relative to the wild type (PDE4D+/+) and heterozygous knockout (PDE4D+/-) mice. This reduced expression was accompanied by a reduction in PDE4 activity, while non-PDE4 activity was unchanged. PDE4D-/- mice exhibited decreased immobility in tail-suspension and forced-swim tests, which is indicative of an antidepressant-like effect on behavior. Desipramine and fluoxetine produced similar antidepressant-like effects in all three genotypes, even though their behavioral baselines differed markedly. By contrast, the PDE4 inhibitor rolipram only produced antidepressant-like effects in PDE4D+/+ mice. Consistent with this, rolipram potentiated isoproterenol-induced cyclic AMP formation only in the PDE4D+/+ mice. These results suggest that PDE4D is an essential mediator of the antidepressant-like effects of rolipram, and that PDE4D-regulated cyclic adenosine monophosphate signaling may play a role in the pathophysiology and pharmacotherapy of depression.

Transgressive segregation, heritability, and number of genes controlling durable resistance to stripe rust in one chinese and two italian wheat cultivars

ABSTRACT Wheat (Triticum aestivum) cvs. Libellula (LB), San Pastore (SP), and Xian Nong 4 (XN4) possess durable resistance to stripe rust, caused by Puccinia striiformis f. sp. tritici, and cv. Ming Xian 169 (MX169) is highly susceptible to the rust. Inheritance of stripe rust resistance was studied by crossing the four cultivars and evaluating the resistance of parental, F(1), F(2), backcross, and F(3) plants in the fields. Transgressive segregation for resistance was observed in the resistant by resistant crosses of LB x XN4 and XN4 x SP, but not in cross LB x SP. These results indicate that (i) the resistance genes in XN4 are different from those in LB and SP, and (ii) LB and SP share common resistance genes. The number of genes segregating for the resistance was estimated by quantitative methods from the data of F(2), backcross, and F(3) populations. LB and XN4 appear to have two to three resistance genes, and SP appears to have two to four resistance genes when crossed with MX169. The resistance gene number in resistant by resistant cross LB x XN4 was four to five, approximately equal to the sum of the genes in LB and XN4. Similarly, the resistance gene number in cross XN4 x SP was approximately equal to the sum of the genes in XN4 and SP. Broad-sense heritability was high in all crosses except LB x SP. Compared with the three MX169-involved crosses, narrow-sense heritability was higher in LB x MX169 and SP x MX169 crosses than in the XN4 x MX169 cross. The LB x XN4 and XN4 x SP crosses showed moderate narrow-sense heritability.

Myomegalin is a novel protein of the golgi/centrosome that interacts with a cyclic nucleotide phosphodiesterase

Subcellular targeting of the components of the cAMP-dependent pathway is thought to be essential for intracellular signaling. Here we have identified a novel protein, named myomegalin, that interacts with the cyclic nucleotide phosphodiesterase PDE4D, thereby targeting it to particulate structures. Myomegalin is a large 2,324-amino acid protein mostly composed of alpha-helical and coiled-coil structures, with domains shared with microtubule-associated proteins, and a leucine zipper identical to that found in the Drosophila centrosomin. Transcripts of 7.5-8 kilobases were present in most tissues, whereas a short mRNA of 2.4 kilobases was detected only in rat testis. A third splicing variant was expressed predominantly in rat heart. Antibodies against the deduced sequence recognized particulate myomegalin proteins of 62 kDa in testis and 230-250 kDa in heart and skeletal muscle. Immunocytochemistry and transfection studies demonstrate colocalization of PDE4D and myomegalin in the Golgi/centrosomal area of cultured cells, and in sarcomeric structures of skeletal muscle. Myomegalin expressed in COS-7 cells coimmunoprecipitated with PDE4D3 and sequestered it to particulate structures. These findings indicate that myomegalin is a novel protein that functions as an anchor to localize components of the cAMP-dependent pathway to the Golgi/centrosomal region of the cell.

A case of endobronchial actinomycosis

Actinomycosis is an infectious disease caused by certain Actinomyces species. Actinomyces are Gram-positive, non-spore forming organisms characterized by obligate or facultative anaerobic rods that normally inhabit anaerobic niches of the human oral cavity. Cervicofacial, abdominal, pelvic and thoracic infections of Actinomyces are not uncommon, but endobronchial actinomycosis is rarely reported. Endobronchial actinomycosis can be misdiagnosed as unresolving pneumonia, endobronchial lipoma or malignancies. Endobronchial actinomycosis should be included in the differential diagnosis of any endobronchial mass. We report a case of a 43-year-old man who presented with a productive cough and pulmonary consolidation at the right lower lobe on chest radiograph. Fiberoptic bronchoscopy revealed obstruction of the right superior segment of the lower bronchus with an exophytic endobronchial mass. Endobronchial actinomycosis was confirmed by demonstration of sulfur granules in the bronchoscopic biopsy of the mass. Intravenous administration of penicillin G followed by oral amoxacillin/clavulanic acid therapy for 3 months resulted in improving symptoms. Infiltrative consolidation on the chest X-ray was markedly decreased.

[The expression of p16 and Rb protein in the tissue of cervical squamous carcinoma]

OBJECTIVE

To study the aberrant expression and coexpression of protein p16 and Rb in cervical squamous carcinomas, and to evaluate whether these alterations provide causative information.

METHODS

The expressions of p16 and Rb protein were detected by treptavidin-peroxidase(S-P) immunohistochemical methods.

RESULTS

1. The p16 protein expression was mainly found in cytoplasm. The positive rate in carcinoma, CIN and normal cervix were 43.1%(25/58), 62.5%(5/8) and 70%(14/20), respectively; the positive expression were decreased in lower grade and clinical advanced cases(P < 0.05). 2. The Rb protein expression was detected in nucleus. The positive rate of Rb protein were 37.9%(22/58), 75%(6/8) and 85(17/20) in tum. The difference of the expression of Rb protein between the cervical squamous carcinoma and the normal cervix was significant(P < 0.05). The positive expression were increased in lower grade cancers(P < 0.05), and decreased in advanced cases(P > 0.05). 3. The positive rates of p16 and Rb protein in cervical squamous carcinoma showed an inverse correlation (vs = -0.4301, P < 0.01).

CONCLUSIONS

1. The abnormal p16 and Rbn expression might play an important role in the tumor genesis and the development of cervical squamous carcinoma. 2. Loss of function of both tumor suppressor genes may be an advanced event in cervical squamous carcinomas and might involve a bad prognosis.

Impaired growth and fertility of cAMP-specific phosphodiesterase PDE4D-deficient mice

In eukaryotic cells, the inactivation of the cyclic nucleotide signal depends on a complex array of cyclic nucleotide phosphodiesterases (PDEs). Although it has been established that multiple PDE isoenzymes with distinct catalytic properties and regulations coexist in the same cell, the physiological significance of this remarkable complexity is poorly understood. To examine the role of a PDE in cAMP signaling in vivo, we have inactivated the type 4 cAMP-specific PDE (PDE4D) gene, a mammalian homologue of the Drosophila dunce. This isoenzyme is involved in feedback regulation of cAMP levels. Mice deficient in PDE4D exhibit delayed growth as well as reduced viability and female fertility. The decrease in fertility of the null female is caused by impaired ovulation and diminished sensitivity of the granulosa cells to gonadotropins. These pleiotropic phenotypes demonstrate that PDE4D plays a critical role in cAMP signaling and that the activity of this isoenzyme is required for the regulation of growth and fertility.

The molecular biology of cyclic nucleotide phosphodiesterases

Recent progress in the field of cyclic nucleotides has shown that a large array of closely related proteins is involved in each step of the signal transduction cascade. Nine families of adenylyl cyclases catalyze the synthesis of the second messenger cAMP, and protein kinases A, the intracellular effectors of cAMP, are composed of four regulatory and three catalytic subunits. A comparable heterogeneity has been discovered for the enzymes involved in the inactivation of cyclic nucleotide signaling. In mammals, 19 different genes encode the cyclic nucleotide phosphodiesterases (PDEs), the enzymes that hydrolyze and inactivate cAMP and cGMP. This is only an initial level of complexity, because each PDE gene contains several distinct transcriptional units that give rise to proteins with subtle structural differences, bringing the number of the PDE proteins close to 50. The molecular biology of PDEs in Drosophila and Dictyostelium has shed some light on the role of PDE diversity in signaling and development. However, much needs to be done to understand the exact function of these enzymes, particularly during mammalian development and cell differentiation. With the identification and mapping of regulatory and targeting domains of the PDEs, modularity of the PDE structure is becoming an established tenet in the PDE field. The use of different transcriptional units and exon splicing of a single PDE gene generates proteins with different regulatory domains joined to a common catalytic domain, therefore expanding the array of isoforms with subtle differences in properties and sensitivities to different signals. The physiological context in which these different isoforms function is still largely unknown and undoubtedly will be a major area of expansion in the years to come.

Subcellular localization of rolipram-sensitive, cAMP-specific phosphodiesterases. Differential targeting and activation of the splicing variants derived from the PDE4D gene

Biochemical and immunofluorescence analyses revealed that phosphodiesterase variants encoded by the PDE4D gene are targeted to discrete subcellular structures. In quiescent FRTL-5 thyroid cells, the rolipram-sensitive phosphodiesterase (PDE) activity (cAMP-PDE) was recovered both in the soluble and particulate fractions of the homogenate. Although an immunoreactive 93-kDa PDE (PDE4D3) variant was recovered in both compartments, a 105-kDa variant with the properties of PDE4D4 was recovered mostly in the particulate fraction. The PDE4D3 form was readily solubilized with nonionic detergents. Conversely, the PDE4D4 form required buffers containing ionic detergents for extraction, suggesting that different mechanisms target these variants to insoluble structures. A 15-min stimulation with thyroid-stimulating hormone (TSH) led to an activation of the cAMP-PDE in both compartments and was correlated with a shift in electrophoretic mobility of the PDE4D3 polypeptide. Long term incubation with TSH caused an increase of the PDE activity in the soluble fraction and the appearance of a 68-kDa immunoreactive polypeptide with the properties of PDE4D2. Immunofluorescence analysis showed, in addition to diffuse staining, a signal localized on regions adjacent to the plasma membrane on cytoskeletal structures and in a perinuclear region of quiescent cells. Long term incubation with TSH caused an increase in the immunofluorescence signal in the soluble compartment. These data demonstrate that three PDE4D splicing variants are targeted to discrete subcellular compartments and that hormones cause the activation of these isoforms in a temporally and spatially dependent manner.

Cloning of a disintegrin metalloproteinase that processes precursor tumour-necrosis factor-alpha

Tumour-necrosis factor-alpha (TNF-alpha) is a cytokine that contributes to a variety of inflammatory disease states. The protein exists as a membrane-bound precursor of relative molecular mass 26K which can be processed by a TNF-alpha-converting enzyme (TACE), to generate secreted 17K mature TNF-alpha. We have purified TACE and cloned its complementary DNA. TACE is a membrane-bound disintegrin metalloproteinase. Structural comparisons with other disintegrin-containing enzymes indicate that TACE is unique, with noteable sequence identity to MADM, an enzyme implicated in myelin degradation, and to KUZ, a Drosophila homologue of MADM important for neuronal development. The expression of recombinant TACE (rTACE) results in the production of functional enzyme that correctly processes precursor TNF-alpha to the mature form. The rTACE provides a readily available source of enzyme to help in the search for new anti-inflammatory agents that target the final processing stage of TNF-alpha production.

Structural features and biochemical properties of TNF-alpha converting enzyme (TACE)

Tumor necrosis factor-alpha is a potent cytokine, secreted primarily by activated monocytes and macrophages, that possesses a broad range of immunomodulating properties. Involvement of this cytokine has been validated in disease states such as arthritis and Crohn's disease and implicated in diverse neuroimmunological pathologies such as multiple sclerosis, Alzheimers and stroke. TNF-alpha is initially synthesized as a 26 kDa precursor molecule that is subsequently processed to the mature form by cleavage of the Ala76 Val77 bond. The 17 kDa carboxy-terminal protein is then secreted to function in a paracrine manner. The enzyme that processes precursor TNF-alpha has previously been identified as a microsomal metalloprotease called TNF-alpha converting enzyme (TACE). We have now purified and partially cloned the enzyme. TACE represents a novel target for therapeutic intervention in a variety of inflammatory and neuroimmunological diseases.

Regulation of distinct cyclic AMP-specific phosphodiesterase (phosphodiesterase type 4) isozymes in human monocytic cells

Many functions of the immune and inflammatory responses are inhibited by agents that increase intracellular levels of cAMP. Recent investigations have revealed that cAMP levels in inflammatory cells are regulated by cyclic nucleotide phosphodiesterases (PDEs) belonging to the PDE4 family (cAMP-specific PDEs). At least four different genes are known to encode PDE4 isozymes, which are characterized by their selectivity for cAMP over cGMP and their sensitivity to the antidepressant drug rolipram. The aim of our studies was to investigate whether monocytic cells could regulate PDE4 activity and whether certain PDE4 isozymes were expressed preferentially over others. Our results showed that treatment of peripheral blood monocytes or closely related Mono Mac 6 cells with dibutyryl-cAMP or other cAMP-elevating agents transiently increased rolipram-sensitive PDE4 activity 2-3-fold, without concomitant increases in cGMP-inhibited PDE (PDE3) activity. PDE4 activity was predominantly cytosolic, whereas PDE3 activity was localized to the particulate fraction. Our Northern and Western blot studies with reagents recognizing three distinct PDE4 gene products (PDE4A, PDE4B, and PDE4D) revealed that their expression is transcriptionally regulated in monocytic cells. Although none of the three isozymes was detectable under normal culture conditions, all of these were up-regulated when Mono Mac 6 cells were exposed to dibutyryl-cAMP. Distinct differences were observed in their temporal patterns of expression. Endotoxin lipopolysaccharide, a potent monocyte stimulus, also enhanced PDE4 activity in monocytic cells. These data indicate that monocytic cells may express different PDE4 isozymes, depending on their state of activation or differentiation. These isozymes could thus regulate intracellular cAMP levels at various stages of monocyte activation and could thereby be important in limiting the inflammatory response.

Elevation of cAMP is required for down-regulation, but not agonist-induced desensitization, of endogenous dopamine D1 receptors in opossum kidney cells. Studies in cells that stably express a rat cAMP phosphodiesterase (rPDE3) cDNA

D1 dopamine receptors stimulate cAMP accumulation in opossum kidney (OK) cells, but this response is attenuated by pretreatment with dopamine. Dopamine pretreatment also causes a reduction in D1 dopamine receptor number. We transfected OK cells with a rat cAMP phosphodiesterase cDNA (rPDE3) in order to determine the contribution of elevations of cAMP to those two phenomena. Wild-type (WT) OK cells were compared to three clones (C, H, and N) which demonstrated stable expression of the rPDE3 phenotype and genotype, rPDE3 RNA expression was confirmed in clones C, H, and N (but not in WT-OK cells) by reverse transcriptase-polymerase chain reaction. A functional rPDE3 phenotype was demonstrated in that dopamine-responsive cAMP accumulation was absent in clones C, H, and N in intact cells, but could be restored by preincubation with cAMP phosphodiesterase inhibitors, or by using washed membranes from those clones. All three clones had increased cAMP phosphodiesterase activity when compared to WT-OK cells (approximately 100% increase), and blunted or absent dopamine (1 microM)-induced protein kinase A activation. After pretreatment with dopamine (1 microM) for 1 h, clones C, H, and N desensitized equally well as WT-OK cells (approximately 40-50% reduction in maximal increase in cAMP). In contrast, down-regulation of D1 dopamine receptors was blunted for clone C (20% receptor loss) and absent for clones H and N, when compared to a 45% loss of receptors for WT-OK cells. These findings suggest that in OK cells pretreated with 1 microM dopamine (i) cAMP accumulation is not necessary for dopamine-induced desensitization, but (ii) is necessary for down-regulation of D1 dopamine receptors, and (iii) that the down-regulation and desensitization processes may be differentially regulated.

Characterization of the structure of a low Km, rolipram-sensitive cAMP phosphodiesterase. Mapping of the catalytic domain

Considerable structural similarities are present in a region of approximately 270 amino acids in most known cyclic nucleotide phosphodiesterase (PDE) sequences, opening the possibility that this region encodes the catalytic domain of the enzyme. To test this hypothesis, the structure of a high affinity cAMP PDE (cAMP-PDE) was analyzed by deletion mutations and site-directed mutagenesis. A ratPDE3 cDNA was mutated using a strategy based on fragment amplification by polymerase chain reaction. The effect of the introduced mutations was determined by expressing wild type and mutated proteins in prokaryotic and eukaryotic cells. The level of expression of the PDE protein was monitored by immunoblot analysis using two specific cAMP-PDE polyclonal antibodies and by measuring the PDE activity. After removal of a 99-amino acid region at the carboxyl terminus flanking the conserved domain, the protein retains its catalytic activity even though its Km and velocity were changed. Internal deletions at the amino terminus of this PDE showed that the enzyme activity was increased when a 97-amino acid fragment (from Tyr49 to Lys145) was removed. Further deletions within the amino terminus produced inactive proteins. Within the domain that appears essential for catalysis, 1 threonine and 2 serine residues are conserved in all PDEs. Substitutions of the invariant threonine (Thr349) present in the most conserved region with alanine, proline, or serine yielded proteins of the correct size and a level of expression comparable to the wild type PDE. However, in both expression systems used, proteins were completely devoid of the ability to hydrolyze cyclic nucleotides, except when the threonine was substituted with a serine. Conversely, mutations of 2 other conserved serine residues (Ser305 and Ser398) present in the catalytic domain either had no effect or produced changes only in Km and Vmax, but did not abolish catalytic activity. In addition, 2 histidine residues (His278 and His311) present in proximity to Thr349 appeared to be essential for the structure of the catalytic domain, since any substitution performed in these residues yielded an inactive enzyme. Mutations of a serine residue (Ser295) in the region homologous to the cAMP binding site of the regulatory subunit of the cAMP-dependent protein kinase demonstrated that this region does not have the same function in the two proteins. These data provide direct evidence that a 37-kDa domain, which in part corresponds to the region of conservation in all PDEs, contains the catalytic domain, and that threonine and histidine residues are probably involved in catalysis and/or are essential for the conformation of an active enzyme.

A polymerase chain reaction strategy to identify and clone cyclic nucleotide phosphodiesterase cDNAs. Molecular cloning of the cDNA encoding the 63-kDa calmodulin-dependent phosphodiesterase

Multiple isozymes of cyclic nucleotide phosphodiesterases (PDEs) are expressed simultaneously in mammalian tissues. To identify and clone these PDEs, a polymerase chain reaction (PCR) strategy was developed using degenerate oligonucleotide primers designed to hybridize with highly conserved PDE DNA domains. Both known and novel PDEs were cloned from rat liver, the mouse K30a-3.3 lymphoma cell line, and a human hypothalamus cDNA library, demonstrating that these PCR primers can be used to amplify the cDNA of multiple PDE isozymes. One unique mouse PDE clone was found to encode a polypeptide identical with the corresponding portion of the bovine brain 63-kDa calmodulin-dependent PDE as reported in the companion article (Bentley, J. K., Kadlecek, A., Sherbert, C. H., Seger, D., Sonnenburg, W. K., Charbonneau, H., Novack, J. P., and Beavo, J. A. (1992) J. Biol. Chem. 267, 18676-18682). This mouse clone was used as a probe to screen a rat brain cDNA library for a full-length clone. The conceptual translation of the nucleotide sequence of the resulting rat clone has an open reading frame of 535 amino acids and maintains a high degree of homology with the bovine 63-kDa calmodulin-dependent PDE, indicating that this protein is likely to be the rat homolog of the 63-kDa calmodulin-dependent PDE. Expression of the full-length clone in Escherichia coli yielded a cGMP hydrolyzing activity that was stimulated severalfold by calmodulin. Northern blot analysis demonstrated that the mRNA encoding this PDE is highly expressed in rat brain and also in the S49.1 T-lymphocyte cell line. These data demonstrate that the PCR method described is a viable strategy to isolate cDNA clones of known and novel members of different families of PDE isozymes. Molecular cloning of these PDEs will provide valuable tools for investigating the roles of these isozymes in regulation of intracellular concentrations of the cyclic nucleotides.

Ontogeny of glucagon messenger RNA in the rat pancreas

The synthesis of proglucagon mRNA was studied in rat pancreas from day 11 of fetal gestation (E11) to maturity. Proglucagon mRNA was first detected on E11, the time that the pancreatic bud forms in developing rats. The synthesis of proglucagon mRNA and its translation product at this early time point in pancreatic development suggests an early differentiation of A cell function. Between E17 prenatally and day 10-14 postnatally, pancreatic proglucagon mRNA abundance was higher than in adult pancreas. Regulation of the abundance of pancreatic proglucagon mRNA therefore appears to underlie the previously documented increases in serum and pancreatic glucagon immunoreactivity in the late fetal and perinatal periods. By day 20 postnatally, pancreatic proglucagon mRNA declined to levels found in adult pancreas. Prenatally between E17 and E21, changes in proglucagon mRNA abundance did not parallel previously reported developmental changes in relative mass of proglucagon-producing pancreatic A cells. This suggests that changes in proglucagon mRNA abundance during these times may be attributed to changes in proglucagon gene transcription or proglucagon mRNA stability per cell. In contrast between E21 and maturity, changes in proglucagon mRNA abundance paralleled previously reported changes in relative A cell mass, suggesting no major changes in proglucagon gene transcription or mRNA stability per cell during these times.

[Traditional Chinese medicine combined with Western medicine in the treatment of severe renal failure in patients with epidemic hemorrhagic fever]

This article reports the treatment of 23 cases (with the control group 20 cases) of severe renal failure in patients with epidemic hemorrhagic fever (EHF) by integrated traditional Chinese medicine and western medicine (TCM-WM), i.e., the renal protective decoction and modern medical treatment during the period of 1988-1989. The effects were as follows: (1) The curative rate was elevated and the morbidity was dropped (P less than 0.01-0.05). (2) Both the period of oliguria and albuminuria were shortened (P less than 0.01-0.05). (3) The severity of the complication, e.g., massive gastro-intestinal hemorrhage, etc., was much reduced (P less than 0.05). (4) The degree of azotemia was getting milder. And the renal function was much improved (P less than 0.05). The mode of action of the renal protective decoction is based on the point of view of the TCM in the treatment of infectious disease.

Ontogeny of glucagon messenger RNA and encoded precursor in the rat intestine

The ontogeny of proglucagon mRNA and encoded precursor was studied in rat intestine from day 11 of fetal gestation (E11) to maturity. The earliest time point for detection of proglucagon antigenic determinants by immunocytochemistry, and of proglucagon mRNA by in situ hybridization histochemistry, was day 14 of fetal gestation (E14), suggesting this time as the point of onset of intestinal proglucagon gene expression and mRNA translation. Between day 17 and 18 of gestation (E17 and E18) there was a significant 10 fold increase in intestinal L cell density, indicating that this time in gestation is one of increased L cell differentiation and/or proliferation. Proglucagon mRNA abundance in developing rat intestine showed a major 8 fold increase between E17 and E18. Similar magnitude of increases in L cell density and proglucagon mRNA abundance suggests that the increase in proglucagon mRNA abundance reflects an increase in L cell numbers rather than increases in proglucagon gene transcription or mRNA stability per cell.

Distribution of glucagonlike peptide I (GLP-I), glucagon, and glicentin in the rat brain: an immunocytochemical study

Although glucagonlike immunoreactants (GLIs) are present in the central nervous system of several mammalian species, their structural relationship with pancreatic proglucagon is not defined, and their precise anatomical distribution has not been studied extensively. To obtain further information about the structure and biological significance of brain GLIs, the anatomical distribution of three different antigenic determinants of pancreatic proglucagon--glucagonlike peptide I (GLP-I), glucagon, and glicentin--was mapped in the brain of colchicine-treated rats by immunocytochemistry using the avidin-biotin-peroxidase method. Neuronal cell bodies immunoreactive with antisera specific for GLP-I, glucagon, and glicentin were found only in the caudal medulla oblongata. Within the caudal medulla immunostained cell bodies were found at levels from approximately 0.55 mm rostral to the obex to 0.45 mm caudal to the obex, and were located within the nucleus of the solitary tract (NTS) and the dorsal (MdD) and ventral (MdV) parts of the medullary reticular nucleus. The NTS contained three times more immunoreactive cell bodies than the MdD and MdV, and these cell bodies were located in the midline, medial, and lateral subnuclei of the caudal third of the NTS. Immunostaining of the same cell bodies in paired adjacent sections incubated with GLP-I and glucagon antisera or glucagon and glicentin antisera provided evidence for coexistence of the three antigens within the same neurons of the NTS. Nerve fibers and terminals immunoreactive with GLP-I, glucagon, and glicentin antisera were widely distributed throughout the rat brain and there was no discernible difference in the distribution of fibers and terminals immunoreactive with each of the three antisera. The highest densities of immunostained fibers and terminals were observed in the hypothalamus, thalamus, and septal regions, and the lowest in the cortex and hindbrain. The localization of neuronal cell bodies containing GLP-I, glucagon, and glicentin within the NTS and the MdD and MdV, and the extensive distribution of immunoreactive fibers and terminals throughout the rat brain suggest a role for these peptides in the integration of autonomic as well as central nervous system functions.