Polymorphisms in the SIRT5 gene and their association with body measurement and ultrasound traits in Qinchuan cattle

Silent information regulator 5 (SIRT5), a member of the Sirtuin family class III nicotinamide adenine dinucleotide-dependent protein deacetylases, plays an important role in metabolic and aging processes in mammals. We identified 4 single-nucleotide polymorphisms (SNPs) (G22010A, G22052A, G22119T, and G22245C) in the 3' untranslated regions of the SIRT5 gene from 572 Qinchuan cattle by sequencing and investigating their association with growth and ultrasound traits. The frequencies of genotype GG and allele G were high at the 4 SNPs. Based on the X(2) test, the genotypic distributions of the 4 SNPs were not in Hardy-Weinberg equilibrium (P < 0.05 or P < 0.01). Association analysis of individual SNPs and haplotype combinations revealed that the 4 loci were significantly associated with some body measurement and ultrasound traits in Qinchuan cattle, and the H1H5 (AG-GA-GG-GG) diplotypes had better performance than other combinations in Qinchuan cattle. Our results demonstrate that SIRT5 may be a candidate for marker-assisted selection in future breeding programs for Qinchuan cattle.

A simple empirical model for the clarification-thickening process in wastewater treatment plants

In wastewater treatment plants (WWTPs), activated sludge is thickened in secondary settling tanks and recycled into the biological reactor to maintain enough biomass for wastewater treatment. Accurately estimating the activated sludge concentration in the lower portion of the secondary clarifiers is of great importance for evaluating and controlling the sludge recycled ratio, ensuring smooth and efficient operation of the WWTP. By dividing the overall activated sludge-thickening curve into a hindered zone and a compression zone, an empirical model describing activated sludge thickening in the compression zone was obtained by empirical regression. This empirical model was developed through experiments conducted using sludge from five WWTPs, and validated by the measured data from a sixth WWTP, which fit the model well (R² = 0.98, p < 0.001). The model requires application of only one parameter, the sludge volume index (SVI), which is readily incorporated into routine analysis. By combining this model with the conservation of mass equation, an empirical model for compression settling was also developed. Finally, the effects of denitrification and addition of a polymer were also analysed because of their effect on sludge thickening, which can be useful for WWTP operation, e.g., improving wastewater treatment or the proper use of the polymer.

Isolated familial pneumothorax in a Taiwanese family with Birt-Hogg-Dubé syndrome

Primary spontaneous pneumothorax usually occurs as a sporadic event, but may be clustered in certain families with an underlying inherited disorder. Birt-Hogg-Dubι (BHD) syndrome is a rare autosomal dominant disease accounting for familial pneumothorax. BHD syndrome, caused by mutation of the folliculin gene, is characterized by skin fibrofolliculoma, pulmonary cysts, pneumothorax, and renal cancer. We describe a BHD-affected Taiwanese family with clinical and genetic study. A rare mutation of the folliculin gene was detected in the patient and members with pulmonary cysts or pneumothorax, but no skin or renal lesions were found. This mutation was reported in a Taiwanese family and might indicate a pneumothorax-predominant phenotype. Isolated pneumothorax is an uncommon initial presentation of BHD syndrome. Family history should be carefully reviewed when managing a patient with pneumothorax.

Cladosporium cladosporioides Identified in China on Tobacco Seeds

Tobacco (Nicotiana tabacum L.) is a leafy, annual, solanaceous plant grown commercially for its leaves. China is the biggest single tobacco market and accounts for more than 40% of the global tobacco consumption (1). Tobacco seed harvested in Guiyang, Guizhou Province, China, are commonly contaminated or infected by various fungal pathogens, which can cause abnormal seedlings with dark brown lesions and stunting of roots and decayed seeds. In 2013, five samples of 500 seeds from tobacco cv. Guiyan 4 were tested for germination on moistened paper on petri dishes. On average, 35% of the seeds from all five samples developed into abnormal seedlings or were decayed and were plated onto potato dextrose agar media and grown for 5 days at 25°C in darkness to confirm the presence of a pathogen. However, one fungus was isolated from an average of 10% of the 500 seeds sampled. It was identified morphologically as Cladosporium cladosporioides (Fresen.) de Vries based on the velvety olive-brown with almost black reverse colony color and dimensions and color of conidia and conidiophores. Conidia formed in long branched chains that readily disarticulate, single celled, elliptical to limoniform, 2 to 8 (avg. 4.3) × 2 to 3 (avg. 2.1) μm. Conidia were pale to olive brown and smooth to verruculose. Ramoconidia were 0 to 1 septate, 7 to 14 (avg. 9.2) × 2 to 4 (avg. 2.6) μm, smooth or sometimes minutely verruculose. Conidiophores were pale to olive brown, macro- and micronemateus, smooth or sometimes verruculose, and of various lengths up to 320 μm long and 2 to 5 μm wide. Primer pair ITS1 and ITS4 was employed to amplify the regions of ITS1-5.8s-ITS2 of the pathogens. Sequences of all three isolates (G3, G10, and G18) (Accession Nos. KF841547, KF841554, and KF841560) were identical to each other and to four sequences in GenBank (JX230994.1, JQ768317.1, JQ768322.1, and AB763555.1). Pathogenicity of the three isolates of C. cladosporioides was verified on tobacco seedlings of 3-week-old grown on wet filter paper in the petri dishes (9 cm in diameter). For each isolate, 20 seedlings incubated in one plate were inoculated with 0.5 ml of a suspension of 10⁵ conidia/ml. Twenty seedlings were treated with sterile water as control treatment. After inoculation, the petri dishes were incubated at 25°C, 100 to 120 μEm^-2 S^-1, RH > 80%, and 16 h light per day for disease development. At 96 h after inoculation, symptoms comprising medium brown to black lesions on the roots were clearly visible on inoculated plants but not on the control plants. All seedlings inoculated died 9 days after inoculation whereas control seedlings remained symptomless. Re-isolation attempts on PDA from roots demonstrated C. cladosporioides to be present in symptomatic seedlings but not in roots of the control plants. Moreover, the characteristics of the cultured fungi were exactly the same as those originally isolated. Isolates G3, G10, and G18 (KF841547, KF841554, and KF841560) were deposited with the Tobacco Diseased Fungi, Guizhou Academy of Tobacco Sciences, Guizhou, China. Previously, C. cladosporioides has also been isolated from macadamia (Macadamia integrifolia Maiden & Betche) racemes in South Africa (4), from diseased papaya (Carica papaya L.) in Taiwan province of China (2), and from seeds of Amaranthus spp. in Poland (3). To the best of our knowledge, this is the first report of C. cladosporioides causing seed disease on tobacco in China and the disease should be considered in existing disease management practices. References: (1) British American Tobacco Annual Report, 8, 2012. (2) R. S. Chen, et al. Plant Dis. 93:426, 2009. (3) W. Pusz. Phytopathologia 54:15, 2009. (4) N. van den Berg et al. Plant Dis. 92:484, 2008.

Elastase induced lung epithelial cell apoptosis and emphysema through placenta growth factor

Chronic pulmonary obstructive disease (COPD) is the fourth leading cause of death worldwide, however, the pathogenic factors and mechanisms are not fully understood. Pulmonary emphysema is one of the major components of COPD and is thought to result from oxidative stress, chronic inflammation, protease–antiprotease imbalance and lung epithelial (LE) cell apoptosis. In our previous studies, COPD patients were noted to have higher levels of placenta growth factor (PlGF) in serum and bronchoalveolar lavage fluid than controls. In addition, transgenic mice overexpressing PlGF developed pulmonary emphysema and exposure to PlGF in LE cells induced apoptosis. Furthermore, intratracheal instillation of porcine pancreatic elastase (PPE) on to PlGF wild type mice induced emphysema, but not in PlGF knockout mice. Therefore, we hypothesized that PPE generates pulmonary emphysema through the upregulation of PlGF expression in LE cells. The elevation of PlGF then leads to LE cell apoptosis. In the present study, we investigated whether PPE induces PlGF expression, whether PlGF induces apoptosis and whether the downstream mechanisms of PlGF are related to LE cell apoptosis. We found that PPE increased PlGF secretion and expression both in vivo and in vitro. Moreover, PlGF-induced LE cell apoptosis and PPE-induced emphysema in the mice were mediated by c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) pathways. Given these findings, we suggest that the increase in PlGF and PlGF-induced JNK and p38 MAPK pathways contribute to PPE-induced LE cell apoptosis and emphysema. Regulatory control of PlGF and agents against its downstream signals may be potential therapeutic targets for COPD.

Detection of Rickettsia spp. and host and habitat associations of fleas (Siphonaptera) in eastern Taiwan

Rickettsia typhi and Rickettsia felis (Rickettsiales: Rickettsiaceae) are two rickettsiae principally transmitted by fleas, but the detection of either pathogen has rarely been attempted in Taiwan. Of 2048 small mammals trapped in eastern Taiwan, Apodemus agrarius Pallas (24.5%) and Mus caroli Bonhote (24.4%) (both: Rodentia: Muridae) were the most abundant, and M. caroli hosted the highest proportion of fleas (63.9% of 330 fleas). Two flea species were identified: Stivalius aporus Jordan and Rothschild (Siphonaptera: Stivaliidae), and Acropsylla episema Rothschild (Siphonaptera: Leptopsyllidae). Nested polymerase chain reaction targeting parts of the ompB and gltA genes showed six fleas to be positive for Rickettsia spp. (3.8% of 160 samples), which showed the greatest similarity to R. felis, Rickettsia japonica, Rickettsia conorii or Rickettsia sp. TwKM01. Rickettsia typhi was not detected in the fleas and Rickettsia co-infection did not occur. Both flea species were more abundant during months with lower temperatures and less rainfall, and flea abundance on M. caroli was not related to soil hardness, vegetative height, ground cover by litter or by understory layer, or the abundance of M. caroli. Our study reveals the potential circulation of R. felis and other rickettsiae in eastern Taiwan, necessitating further surveillance of rickettsial diseases in this region. This is especially important because many novel rickettsioses are emerging worldwide.

In vitro cytotoxic activity of novel protoflavone analogs - selectivity towards a multidrug resistant cancer cell line

BACKGROUND

Protoapigenone (PA), a natural flavonoid possessing an unusual p-quinol moiety on its B ring, is a prospective novel lead compound against cancer currently in development, together with WYC0209, a potent synthetic PA analog. Structure activity relationships (SAR) concerning different 1'-O-alkyl side-chains were also studied on two sets of derivatives.

MATERIALS AND METHODS

Fifteen 1'-O-alkyl protoflavone derivatives were synthesized from genkwanin or 4'-hydroxy-6-methylflavone, thirteen of which are new compounds. All compounds were tested for their cytotoxic effect on four human cancer cell lines, such as HepG2 and Hep3B (hepatic), A549 (lung) and MDA-MB-231 (breast) cell lines, with doxorubicin as a positive control. All compounds, as well as PA, WYC0209 and fourteen of their previously reported analogs were also tested on a multidrug-resistant (MDR) sub-cell line of L5178 mouse T-cell lymphoma and on its parental counterpart (PAR).

RESULTS

In general, derivatives bearing a free hydroxyl group at C-1' exerted the strongest activities, while C-1'-substituted compounds were found to be much weaker. Derivatives of 6-methylflavone exhibited mild, but statistically significant selectivity towards the MDR cell line.

CONCLUSION

The results are in agreement with our previous findings for fundamental SAR of protoflavones. 6-Methylated protoflavones may serve as valuable leads for developing selective compounds against MDR cancer. Identical activity of other derivatives on the PAR and MDR cell lines suggests that cancer cells cannot exhibit resistance to protoflavones by ABCB1 efflux pump overexpression.

Association between a single nucleotide polymorphism in the bovine chemerin gene and carcass traits in Qinchuan cattle

Qinchuan is a red or yellow draft and beef breed in China. In order to identify a predictor of carcass traits on the basis of associations between carcass traits and gene polymorphism, variation in the bovine chemerin gene was investigated using PCR-single-strand conformational polymorphism and DNA sequencing. An SNP of A868G located in exon 2 of the Bos taurus chemerin gene was detected in 716 samples of six breeds (Jiaxian red, Luxi, Nan yang, Qinchuan, Simmental and Luxi crossbred steers, and Xia'nan), all in China, and three genotypes (AA, AG and GG) were found. Based on the χ(2) test, the AA/AG/GG genotype frequencies of all six breeds were found to be in Hardy-Weinberg equilibrium. A possible association of A868G with some carcass traits was investigated in 106 Qinchuan cattle. Animals with the AG genotype were found to have significantly lower mean loin eye area and meat tenderness compared to those with the AA and GG genotypes. However, there was no significant association between any individual haplotype and backfat thickness, water holding capacity or marbling score. We suggest that A868G could be used as a molecular marker in marker-assisted selection for carcass traits.

Lack of an association between a single nucleotide polymorphism in the bovine myogenic determination 1 (MyoD1) gene and meat quality traits in indigenous Chinese cattle breeds

The myogenic determination 1 (MyoD1) gene is a member of the MyoD gene family. It encodes for skeletal muscle-specific transcription factors containing highly conserved basic helix-loop-helix regions that perform important roles in the initiation, maintenance, and regulation of phenotypic traits. We investigated a new single nucleotide polymorphism (SNP) in the MyoD1 gene to evaluate whether this polymorphism affects meat quality traits in five Chinese indigenous cattle breeds, namely Qinchuan (QC), Xia-Nan (XN), Nan-yang (NY), Luxi (LX), and Jia-xian red (JXR). A C→G transversion at position 624 was detected in exon 1 of the MyoD1 gene; it causes an amino acid substitution ((624)serine/(624)cysteine). Least squares analysis showed that this SNP is not significantly associated with back fat thickness, eye muscle area, intramuscular fat, or marbling. The A/B allelic frequencies in the five breeds were 0.810/0.189, 0.779/0.220, 0.768/0.231, 0.820/0.180, and 0.801/0.198, respectively. Based on the χ(2) test, the genotype distributions of four cattle breeds (LX, NY, QC, and XN) did not agree with Hardy-Weinberg equilibrium (P < 0.05); one breed (JXR) did not deviate significantly from Hardy-Weinberg equilibrium (P > 0.05). The genotypic frequencies among all five cattle breeds showed moderate diversity (0.25 < polymorphism information content < 0.5). We concluded that the C624G SNP of the MyoD1 gene does not influence meat quality traits in indigenous Chinese cattle breeds; however, this SNP could be included in breed composition and population admixture analyses due to the marked differences in allelic frequencies among these five breeds.

Identification of potential hosts and vectors of scrub typhus and tick-borne spotted fever group rickettsiae in eastern Taiwan

Scrub typhus and tick-borne spotted fever group (SFG) rickettsioses are transmitted by chiggers (larval trombiculid mites) and hard ticks, respectively. We assessed exposure to these disease vectors by extensively sampling both chiggers and ticks and their small mammal hosts in eastern Taiwan during 2007 and 2008. The striped field mouse Apodemus agrarius Pallas (Rodentia: Muridae) was the most common of the small mammals (36.1% of 1393 captures) and presented the highest rate of infestation with both chiggers (47.8% of 110 760) and ticks (78.1% of 1431). Leptotrombidium imphalum Vercammen-Grandjean & Langston (Trombidiformes: Trombiculidae) and immature Rhipicephalus haemaphysaloides Supino (Ixodida: Ixodidae) were the most abundant chiggers (84.5%) and ticks (>99%) identified, respectively. Immunofluorescent antibody assay revealed high seropositive rates of rodents against Orientia tsutsugamushi Hyashi (Rickettsiales: Rickettsiaceae), the aetiological agent of scrub typhus (70.0% of 437 rodents), and tick-borne SFG rickettsiae (91.9% of 418 rodents). The current study represents a first step towards elucidating the potential hosts and vectors in the enzootic transmission of O. tsutsugamushi and tick-borne SFG rickettsiae in Taiwan. Further studies should focus on characterizing pathogens in L. imphalum and R. haemaphysaloides, as well as the proclivity of both vectors to humans. Uncovering the main hosts of adult ticks is also critical for the prevention of SFG rickettsial infections.

Effect of aging on morphology of organo-montmorillonite modified bitumen by atomic force microscopy

The morphology of unmodified and organo-montmorillonite modified bitumens was investigated by atomic force microscopy. The influence of thin film oven test and ultraviolet aging on the morphology of the binders was also analysed. The atomic force microscopy results showed that bitumen displayed a 'bee-like' structure and the dimension of the 'bee-like' structures was decreased to some extent with the introduction of organo-montmorillonite. Organo-montmorillonite showed a better interaction with the dispersed domains in comparison with the matrix in bitumen, which led to an obvious increase in the contrast between the dispersed domains and the matrix in bitumen. Compared with the unmodified bitumen, the single-phase trend in the organo-montmorillonite modified bitumen could be effectively prevented during thin film oven test and ultraviolet aging, indicating its good aging resistance which was in accordance with changes in physical properties of the organo-montmorillonite modified bitumen before and after aging.

Fetal gender screening by ultrasound at 11 to 13+6weeks

BACKGROUND

To survey the accuracy of fetal gender determination during first trimester screening and scan for congenital anomalies.

METHODS

A prospective observational study was performed on 496 singleton pregnancies at the first trimester ultrasound screening. The doctor was a certified sonographer of first trimester screening by the Fetal Medicine Foundation(FMF). Ultrasound examination was performed on a GE Voluson 730 Pro, transabdominally, between 11 and 13(+6) weeks. Both transverse and mid-sagittal planes of a section of the fetal genital tubercle were performed to identify the gender. The subsequent gender at birth was obtained from karyotyping reports or hospital birth records.

RESULTS

During the study, 496 patients requested gender information at the time of first trimester screening. Of the patients it was possible to determine gender (441 out of 496), the scan achieved an overall success rate of 91.8% in correctly identifying gender. The success rate for correctly identifying fetal gender (where identification was possible) increased with gestational age, from 71.9% at 11 weeks, 92% at 12 weeks, and 98.3% at 13 weeks, respectively, where gestational age was calculated from the crown-rump length in conjunction with menstrual or ovulation dating (p<0.001). Of the 55 cases where no identification of gender was possible, 39 were in the 11-week gestational age group, representing 40.6% of this category. The overall fetal gender accuracy rate for male fetus was slightly better than female (92.5 versus 91.2%), but was not statistically significant.

CONCLUSIONS

This study demonstrated that the gestational age of the fetus has a material effect on the accuracy rate of gender determination. At 12 weeks and over, the average success rate for correctly identifying gender, where gender identification was possible, was 94.8%, with the accuracy at 13 weeks of 98.3% approaching that achieved by invasive testing. Fetal gender identification at 11

Adult Pseudomonas aeruginosa meningitis: high incidence of underlying medical and/or postneurosurgical conditions and high mortality rate

We analyzed the clinical and laboratory characteristics, therapeutic outcome and prognostic factors of 25 cases of cerebrospinal fluid (CSF) culture-proven Pseudomonas aeruginosa adult bacterial meningitis (ABM). Twelve P. aeruginosa strains, isolated from clinical CSF specimens, were tested for antibiotic susceptibility. The 25 cases included 17 men and 8 women, aged 17 to 86 years (median=51). Of the 25 cases of P. aeruginosa ABM, 18 were the result of postneurosurgical infection and the other 7 were spontaneous infections. The latter 7 cases had serious underlying medical conditions. The antibiotic susceptibility rates of the 12 strains were as follows: ceftriaxone 16.7% (2/12), ceftazidime 91.7% (11/12), cefepime 83.3% (10/12), imipenem 83.3% (10/12), meropenem 83.3% (10/12) and ciprofloxacin 66.7% (8/12). The therapeutic results showed an overall mortality rate of 40% (10/25). The emergence of third-generation cephalosporin-resistant P. aeruginosa strains cultured from clinical CSF specimens in recent years has resulted in a therapeutic challenge in the treatment of ABM.

The expression of genes related to adipocyte differentiation in pigs1

The purpose of this study was to detect differential expression of genes related to adipocyte differentiation in pigs by suppression subtractive hybridization. Adipocytes and stromal vascular cells (a fraction containing preadipocytes) from pig adipose tissue were isolated for mRNA extraction. The cDNA from preadipocytes was subtracted from the cDNA from adipocytes. The subtracted gene fragments were cloned into pGEM-T Easy TA cloning vector. We selected 384 clones for gene sequence determination and for further analysis. These genes were subjected to a differential screening procedure to confirm the differential expression of genes between the 2 cell types. We found that at least 36 genes were highly expressed in the adipocytes compared with preadipocytes. Among these, 6 genes including 2 novel genes with the greatest differences were selected and confirmed by Northern analysis. We found that angiotensin I-converting enzyme (ACE), ataxia-telangiectasia mutated protein (ATM), calpain 1, and stearoyl coenzyme A desaturase 1 (SCD1) were highly expressed in adipocytes compared with preadipocytes (P < 0.05). The relative mRNA abundance of ACE, ATM, calpain 1, SCD1, and 2 novel genes discovered in the current study was increased at the later stages of adipocyte differentiation (P < 0.05). The results confirmed that the genes involved in lipid metabolism and adipocyte differentiation were highly expressed in porcine adipocytes. However, further investigation is needed to demonstrate specific functions of the novel genes discovered in the current study.

Broad angular multilayer analyzer for soft X-rays

Using numerical optimization algorithm, non-periodic Mo/Si, Mo/Be, and Ni/C broad angular multilayer analyzers have been designed. At the wavelength of 13 nm and the angular range of 45~49 degrees , the Mo/Si and Mo/Be multilayer can provide the plateau s-reflectivity of 65% and 45%, respectively. At 5.7 nm, the s-reflectivity of Ni/C multilayer is 16% in the 44~46 degrees range. The non-periodic Mo/Si broad angular multilayer was also fabricated using DC magnetron sputtering, and characterized using the soft X-ray polarimeter at BESSY. The s-reflectivity is higher than 45.6% over the angular range of 45~49 degrees at 13 nm, where, the degree of polarization is more than 99.98%.

Cholinesterase inhibitor affects the amyloid precursor protein isoforms in patients with Alzheimer's disease

An altered platelet ratio of amyloid precursor protein (APP) isoforms might be a diagnostic, predictive, or therapeutic marker for Alzheimer's disease (AD). Our purpose was to test the hypothesis that this ratio might serve as a therapeutic marker for AD patients treated with the cholinesterase inhibitor, galantamine. Thirty-nine patients (mean age 76.6 +/- 9.4 years) with AD were treated with galantamine for 12 weeks. Patients were evaluated at baseline, 4 and 12 weeks by cognitive testing along with a determination of their platelet APP isoform ratio. Western blotting was performed to calculate the APP isoform ratio. At the end of the treatment, cognitive scores significantly improved, and the ratio of the high-molecular-weight (130 kDa) isoform to the low-molecular-weight (110-106 kDa) isoforms increased. These results suggest that cholinesterase inhibition might be involved in APP processing.

DNA haplotype analysis of CAG repeat in Taiwanese Huntington's disease patients

We studied the expanded CAG repeat and adjacent CCG repeat in 53 Huntington's disease (HD) patients and 172 unrelated normal subjects matched to the patients for ethnic origin. The range of the CAG repeat varied from 38 to 109 in the HD patients and from 10 to 29 in the control group. A significant negative correlation was found between the age at onset and the CAG expansion, with no significant influence of the adjacent CCG repeat on the age at onset by multiple regression analysis. Allelic association using CCG repeat and 2 flanking dinucleotide repeat markers within 150 kb of the HD gene revealed linkage disequilibrium for 2 of 3 markers. Haplotype analysis of 24 HD families using these markers identified 3 major haplotypes underlying 87.5% of HD chromosomes. The data suggested frequent haplotypes in the Taiwanese population on which one or more mutational events leading to the disease occurred.

In vivo dosimetry for external photon treatments of head and neck cancers by diodes and TLDS

In vivo dosimetry was implemented for treatments of head and neck cancers in the large fields. Diode and thermoluminescence dosemeter (TLD) measurements were carried out for the linear accelerators of 6 MV photon beams. ESTRO in vivo dosimetry protocols were followed in the determination of midline doses from measurements of entrance and exit doses. Of the fields monitored by diodes, the maximum absolute deviation of measured midline doses from planned target doses was 8%, with the mean value and the standard deviation of -1.0 and 2.7%. If planned target doses were calculated using radiological water equivalent thicknesses rather than patient geometric thicknesses, the maximum absolute deviation dropped to 4%, with the mean and the standard deviation of 0.7 and 1.8%. For in vivo dosimetry monitored by TLDs, the shift in mean dose remained small but the statistical precision became poor.

Immune function of thyroid stimulating hormone and receptor

Thyroid stimulating hormone (TSH) is a central component of the hypothalamus-pituitary-thyroid axis. Although TSH is known for its important biological effects as a neuroendocrine used to regulate thyroid hormone activity and subsequent metabolic functions, TSH also has been shown to be produced and used by cells ofthe mammalian immune system. Moreover, recent findings have linked the use of TSH by cells of the immune system in humans and mice to a group of monocytic cells and lymphocytes--primarily dendritic cells, macrophages, and subset of naïve peripheral T cells. Other studies have demonstrated the capacity of dendritic cells and monocytes to produce biologically active TSH, thereby pointing to a process of paracrine or autocrine TSH-mediated communication during the earliest stages of an immune response to antigen. In this article, these and other features of TSH immune-endocrine interactions are discussed in the context of an intrinsic TSH immunological pathway. Additionally, a hypothesis is proposed in which TSH produced by cells of the immune system during acute antigen exposure plays a dual role, consisting on the one hand of TSH communication during antigen-driven immune activation while concomitantly serving to regulate physiological homeostasis by modulating and adjusting thyroid hormone activity.

Multiple levels of activation of murine CD8(+) intraepithelial lymphocytes defined by OX40 (CD134) expression: effects on cell-mediated cytotoxicity, IFN-gamma, and IL-10 regulation

The involvement of OX40 (CD134) in the activation of CD8(+) intestinal intraepithelial lymphocytes (IELs) has been studied using freshly isolated IELs and in vitro CD3-stimulated IELs. Although freshly isolated CD8(+) IELs exhibited properties of activated T cells (CD69 expression and ex vivo cytotoxicity), virtually all CD8(+) IELs from normal mice were devoid of other activation-associated properties, including a lack of expression of OX40 and the ligand for OX40 (OX40L) and an absence of intracellular IFN-gamma staining. However, OX40 and OX40L expression were rapidly up-regulated on CD8 IELs following CD3 stimulation, indicating that both markers on IELs reflect activation-dependent events. Unlike IELs, activated lymph node T cells did not express OX40L, thus indicating that OX40-OX40L communication in the intestinal epithelium is part of a novel CD8 network. Functionally, OX40 expression was exclusively associated with IELs with active intracellular IFN-gamma synthesis and markedly enhanced cell-mediated cytotoxicity. However, OX40 costimulation during CD3-mediated activation significantly suppressed IL-10 synthesis by IELs, whereas blockade of OX40-OX40L by anti-OX40L mAb markedly increased IL-10 production. These findings indicate that: 1) resident CD69(+)OX40(-) IELs constitute a population of partially activated T cells poised for rapid delivery of effector activity, 2) OX40 and OX40L expression defines IELs that have undergone recent immune activation, 3) OX40(+) IELs are significantly more efficient CTL than are OX40(-) IELs, and 4) the local OX40/OX40L system plays a critical role in regulating the magnitude of cytokine responses in the gut epithelium.