Reducing brain Aβ burden ameliorates high-fat diet-induced fatty liver disease in APP/PS1 mice

High-fat diet (HFD)-induced fatty liver disease is a deteriorating risk factor for Alzheimer's disease (AD). Mitigating fatty liver disease has been shown to attenuate AD-like pathology in animal models. However, it remains unclear whether enhancing Aβ clearance through immunotherapy would in turn attenuate HFD-induced fatty liver or whether its efficacy would be compromised by long-term exposure to HFD. Here, the therapeutic potentials of an anti-Aβ antibody, NP106, was investigated in APP/PS1 mice by HFD feeding for 44 weeks. The data demonstrate that NP106 treatment effectively reduced Aβ burden and pro-inflammatory cytokines in HFD-fed APP/PS1 mice and ameliorated HFD-aggravated cognitive impairments during the final 18 weeks of the study. The rejuvenating characteristics of microglia were evident in APP/PS1 mice with NP106 treatment, namely enhanced microglial Aβ phagocytosis and attenuated microglial lipid accumulation, which may explain the benefits of NP106. Surprisingly, NP106 also reduced HFD-induced hyperglycemia, fatty liver, liver fibrosis, and hepatic lipids, concomitant with modifications in the expressions of genes involved in hepatic lipogenesis and fatty acid oxidation. The data further reveal that brain Aβ burden and behavioral deficits were positively correlated with the severity of fatty liver disease and fasting serum glucose levels. In conclusion, our study shows for the first time that anti-Aβ immunotherapy using NP106, which alleviates AD-like disorders in APP/PS1 mice, ameliorates fatty liver disease. Minimizing AD-related pathology and symptoms may reduce the vicious interplay between central AD and peripheral fatty liver disease, thereby highlighting the importance of developing AD therapies from a systemic disease perspective.

Reduced mitochondria membrane potential and lysosomal acidification are associated with decreased oligomeric Aβ degradation induced by hyperglycemia: A study of mixed glia cultures

Diabetes is a risk factor for Alzheimer’s disease (AD), a chronic neurodegenerative disease. We and others have shown prediabetes, including hyperglycemia and obesity induced by high fat and high sucrose diets, is associated with exacerbated amyloid beta (Aβ) accumulation and cognitive impairment in AD transgenic mice. However, whether hyperglycemia reduce glial clearance of oligomeric amyloid-β (oAβ), the most neurotoxic Aβ aggregate, remains unclear. Mixed glial cultures simulating the coexistence of astrocytes and microglia in the neural microenvironment were established to investigate glial clearance of oAβ under normoglycemia and chronic hyperglycemia. Ramified microglia and low IL-1β release were observed in mixed glia cultures. In contrast, amoeboid-like microglia and higher IL-1β release were observed in primary microglia cultures. APPswe/PS1dE9 transgenic mice are a commonly used AD mouse model. Microglia close to senile plaques in APPswe/PS1dE9 transgenic mice exposed to normoglycemia or chronic hyperglycemia exhibited an amoeboid-like morphology; other microglia were ramified. Therefore, mixed glia cultures reproduce the in vivo ramified microglial morphology. To investigate the impact of sustained high-glucose conditions on glial oAβ clearance, mixed glia were cultured in media containing 5.5 mM glucose (normal glucose, NG) or 25 mM glucose (high glucose, HG) for 16 days. Compared to NG, HG reduced the steady-state level of oAβ puncta internalized by microglia and astrocytes and decreased oAβ degradation kinetics. Furthermore, the lysosomal acidification and lysosomal hydrolysis activity of microglia and astrocytes were lower in HG with and without oAβ treatment than NG. Moreover, HG reduced mitochondrial membrane potential and ATP levels in mixed glia, which can lead to reduced lysosomal function. Overall, continuous high glucose reduces microglial and astrocytic ATP production and lysosome activity which may lead to decreased glial oAβ degradation. Our study reveals diabetes-induced hyperglycemia hinders glial oAβ clearance and contributes to oAβ accumulation in AD pathogenesis.

A high-sucrose diet aggravates Alzheimer's disease pathology, attenuates hypothalamic leptin signaling, and impairs food-anticipatory activity in APPswe/PS1dE9 mice

High-fat and high-sugar diets contribute to the prevalence of type 2 diabetes and Alzheimer's disease (AD). Although the impact of high-fat diets on AD pathogenesis has been established, the effect of high-sucrose diets (HSDs) on AD pathogenesis remains unclear. This study sought to determine the impact of HSDs on AD-related pathologies. Male APPswe/PS1dE9 (APP/PS1) transgenic and wild-type mice were provided with HSD and their cognitive and hypothalamus-related noncognitive parameters, including feeding behaviors and glycemic regulation, were compared. HSD-fed APP/PS1 mice showed increased neuroinflammation, as well as increased cortical and serum levels of amyloid-β. HSD-fed APP/PS1 mice showed aggravated obesity, hyperinsulinemia, insulin resistance, and leptin resistance, but there was no induction of hyperphagia or hyperleptinemia. Leptin-induced phosphorylation of signal transducer and activator of transcription 3 in the dorsomedial and ventromedial hypothalamus was reduced in HSD-fed APP/PS1 mice, which might be associated with attenuated food-anticipatory activity, glycemic dysregulation, and AD-related noncognitive symptoms. Our study demonstrates that HSD aggravates metabolic stresses, increases AD-related pathologies, and attenuates hypothalamic leptin signaling in APP/PS1 mice.

[Study of bone mineral density and serum bone turnover markers in newly diagnosed systemic lupus erythematosus patients]

OBJECTIVE

To investigate the changes of bone mineral density (BMD) and serum bone turnover factor in newly diagnosed systemic lupus erythematous (SLE) patients.

METHODS

Eighty newly diagnosed SLE patients and 80 age and gender matched healthy controls were enrolled. None of the SLE patients had ever received glucocorticoid, immunosuppressive agents or vitamin D. BMD was measured at radius,lumbar spine and hip by dual X ray absorptiometry (DXA). Bone turnover markers including serum levels of tartrate-resistant acid phosphatase 5b (TRAP5b),bone alkaline phosphatase (BAP) and 25-hydroxy vitamin D3 (25-OH-VD3) were measured by enzyme-linked immunosorbent assay (ELISA). Logistic regression was employed to analyze the risk factors associated with decreased BMD.

RESULTS

Mean age of the SLE patients was (32.8±12.4) years, and 85% were female, none of whom were post-menopausal. BMD was significantly reduced in all the measured sites, compared with the healthy controls. Sixteen (20%) of the patients were osteopenic in at least one site measured locations. The serum levels of 25-OH-VD3 were markedly reduced in the newly diagnosed SLE patients than those of the normal controls [(46.1+12.3) nmol/L vs. (25.4+11.2) nmol/L, P<0.001)]. The serum levels of 25-OH-VD3 in the SLE patients with nephritis were much lower than those without nephritis (P=0.04). A significant negative correlation was demonstrated between the serum concentration of 25-OH-VD3 and the disease activity scores as measured by SLE disease activity index (SLEDAI) (r=-0.3,P=0.001). The serum TRAP5b concentration was positively correlated with SLEDAI (r=0.435,P=0.003). Age (P=0.058) and SLEDAI (P=0.085) were probably associated with decreased BMD in Logistic regression analysis.

CONCLUSION

The study showed reduced BMD in untreated SLE patients. The role of chronic inflammation was of probable importance in bone metabolism.

[Clinical and immunological characteristics of patients with systemic lupus erythematosus in Tibet plateau, China]

OBJECTIVE

To describe the clinical, immunological characteristics and organ involvement of patients with systemic lupus erythematosus (SLE) in Tibet plateau, China.

METHODS

We retrospectively investigated 70 patients admitted in the Tibet Autonomous Region People's Hospital between May 2014 and April 2016. In the study, 120 hospitalized patients with SLE from the Department of Rheumatology and Immunology of the Peking University People's Hospital were randomly selected as the control (plain) group. The major organ involvement, clinical and immunological characteristics were compared between the two groups.

RESULTS

The female to male ratio of Tibet plateau group was 10.7, while the corresponding ratio of plain group was 11.0. The mean age at disease diagnosis was (32.21±11.40) and (35.38±13.25) years, respectively. the most common initial manifestations of SLE were arthritis (78.6%), alopecia (55.7%) and malar rash (48.6%) in Tibet plateau group, the prevalence of arthritis and alopecia was significantly higher than in plain group (P<0.05). The incidence of neuropsychiatric and kidney involvement was significantly lower in Tibet plateau group compared with plain group (P<0.05). As for the serological manifestations, the positivity of anti-double-stranded DNA (dsDNA) (57.1%), anti-Smith (Sm) antibody (55.7%), anti-Sjögren syndrome A (SSA) antibody (72.3%), anti-Sjögren syndrome B (SSB) antibody (41.4%) and anti-u1-ribosenuclear protein (u1RNP) antibody (45.7%) was significantly higher in Tibet plateau group (P<0.05). While the incidence of low serum complement C3 (61.4%), C4 (38.6%) less frequent in Tibet plateau group. Mean SLE disease activity index (SLEDAI) score was similar in the Tibet plateau group (12.18±5.58) and plain group (12.69±7.28). Moreover, there were 13 (18.6%) SLE patients suffering from tuberculosis and 7 (10%) SLE patients infected with hepatitis B virus in Tibet plateau group. The number of recent-onset SLE patients with lower 25-dihydroxy-vitamin D3 (25-OH-VD3) in Tibet plateau group was fewer than that in the plain group (76.7% vs. 90.0%, P=0.046). Serum 25-OH-VD3 levels in Tibet plateau plateau group were (31.14±18.74) nmol/L, those in plain group were (26.91±14.27) nmol/L, and the difference was not significant.

CONCLUSION

The age, gender and SLEDAI scores in Tibet plateau group was similar to those in plain group. But there are significant differences in clinical manifestations, distributions of antibodies and immunological changes between Tibet plateau group and plain group. The patients with lower serum 25-OH-VD3 levels were more in plain group than in Tibet plateau group, while there was no significant difference in the 25-OH-VD3 level between the two groups.

[Increased serum C-C chemokine ligand 19 levels correlated with B cell abnormalities in systemic lupus erythematosus]

OBJECTIVE

To detect the levels of serum C-C chemokine ligand 19 (CCL19) in patients with systemic lupus erythematosus (SLE) and to evaluate the correlation between CCL19 expression and clinical features and laboratory parameters, trying to reveal the possible role of CCL19 in the pathogenesis of systemic lupus erythematosus.

METHODS

The levels of serum CCL19 were measured by enzyme linked immunosorbent assay (ELISA) in 90 patients with SLE and 30 healthy controls. These SLE patients included 75 patients who received treatment with glucocorticoids and disease-modifying anti-rheumatic drug (DMARD) and 15 patients without therapy. The frequencies of peripheral blood B cells and the B cell subsets were assessed in the patients with SLE by flow cytometry. The correlation between the clinical data, laboratory parameters, B cell subset frequencies and serum CCL19 levels were analyzed. Indepen-dent samples t test, paired t test, Pearson and Spearman correlation were used for statistical analyses.

RESULTS

The levels of CCL19 were markedly higher in the SLE patients without therapy and the patients with therapy than in the health controls[(596.25±409.19) ng/L and (422.90±395.84) ng/L vs. (157.79±125.23) ng/L, all P<0.001]. Serum CCL19 levels in the SLE patients without therapy were higher than the SLE patients who accepted glucocorticoids and DMARD treatment (P<0.05). The levels of serum CCL19 were positively correlated with anti-double stranded deoxyribonucleic acid (dsDNA), anti-nucleosome antibody (AnuA), IgA, IgG and IgM (r=0.38, P=0.007; r=0.332, P=0.029; r=0.519, P=0.007; r=0.461, P=0.018, respectively). Serum CCL19 levels in the SLE patients with photosensitivity, arthritis and secondary Sjögren's syndrome were higher than the SLE patients without photosensitivity, arthritis and secondary Sjögren's syndrome, respectively [(562.25±399.12) ng/L, (565.6±435.24) ng/L and (694.9±531.02) ng/L vs. (394.7±281.42) ng/L, (385.90±325.33) ng/L and (424.8±305.46) ng/L, all P<0.05]. The levels of serum CCL19 were positively correlated with the percentage of CD27-B cells and CD27-IgD-double-negative memory B cells (r=0.519, P=0.007; r=0.461, P=0.018, respectively). However, the levels of serum CCL19 were negatively correlated with the percentage of CD27⁺ memory B cells and CD27⁺IgD^- switched memory B cells (r=-0.433, P=0.027; r=-0.616, P=0.001, respectively).

CONCLUSION

The increased serum CCL19 levels in SLE patients were associated with the production of autoantibodies, and CCL19 might be involved in the pathogenesis of SLE by disturbing the homeostasis of B cell subsets.

[Application study of qualitatively diagnosing prostate cancer using ultrahigh b-value DWI]

Objective: To explore the value of ultrahigh b-value DWI in diagnosis of prostate cancer. Methods: From October 2015 to October 2016, a total of 84 cases from Affiliated Changshu Hospital of Soochow University(39 cases of prostate cancer with a total of 57 lesions, 45 cases of benign prostate hyperplasia) were examined with T(2)WI, high b-value DWI (b=1 000 s/mm(2)) and ultrahigh b-value DWI (b=2 000 s/mm(2)) .Three image sets were rated respectively based on PI-RADS V2 by two radiologists and the scores were compared with biopsy results.The differences of the area under the ROC curve (AUC) among the three groups of each observer were compared by Z test. Results: The difference of AUC between ultrahigh b-value DWI and T(2)WI in the diagnosis of peripheral and transitional zone cancer was statistically significant between the two observers (P=0.009 9, 0.008 2, 0.010 8 and 0.004 5 respectively), and there was no significant difference of AUC between ultrahigh b-value DWI and high b-value DWI in the diagnosis of peripheral and transitional zone cancer.The inter-reader agreement was found to be perfect for all lesions, peripheral zone lesions and transition zone lesions at ultrahigh b-value DWI (kappa values were 0.738, 0.709 and 0.768 respectively). Conclusion: The diagnostic performance of ultrahigh b-value DWI is superior to high b-value DWI and T(2)WI in both peripheral zone and transition zone cancers.

One-step synthesis and luminescence properties of tetragonal double tungstates nanocrystals

A versatile one-step thermolysis protocol is demonstrated to produce a uniform dispersion of tetragonal double tungstates NaRE(WO4)2 (RE = rare earth) nanocrystals (NCs). Oriented attachment in the [001] direction occurred. Doping with luminescent RE(3+) ions resulted in highly luminescent NCs showing characteristic line emission of the dopant as well as a blue emission assigned to surface adsorbed organic species.

Development of polymorphic SSR markers in the razor clam (Sinonovacula constricta) and cross-species amplification

Next-generation sequencing provides large-scale sequencing data with relative ease and at a reasonable cost, making it possible to identify a large amount of SSR markers in a timely and cost-effective manner. On the basis of the transcriptome database of Sinonovacula constricta obtained by Illumina/Solexa pyrosequencing, 60 polymorphic SSR markers were developed and characterized in 30 individuals. The number of alleles per polymorphic locus ranged from 2 to 7 with an average of 3.75 alleles. The observed and expected heterozygosities varied from 0.050 to 1.000 and from 0.050 to 0.836, respectively. Nineteen loci significantly deviated from Hardy-Weinberg equilibrium (P < 0.01) after Bonferroni's correction for multiple tests. In addition, interspecific transferability revealed that 20 polymorphic loci in Solen linearis were first characterized in this study. To the best of our knowledge, this is the highest number of SSRs in S. constricta and the first report of cross-species amplification. These novel polymorphic SSR markers will be particularly useful for conservation genetics, evolutionary studies, genetic trait mapping, and marker assisted selection in the species.

Development of novel polymorphic microsatellite markers for the blood clam Tegillarca granosa by pyrosequencing

Large amounts of expressed sequence tags (ESTs) generated using next-generation sequencing technologies provide a cost-effective and valuable genomic resource for the development of microsatellite markers. In this study, we isolated 115 novel polymorphic microsatellite markers for the blood clam Tegillarca granosa from ESTs in 454 sequencing data. All the loci were characterized in 30 individual clams from a natural population in Xiangshan (Zhejiang Province, China). The number of alleles per locus varied from 2 to 10, with an average of 3.78. The observed and expected heterozygosities ranged from 0 to 1 and from 0.040 to 0.799, respectively. The polymorphic information content (PIC) ranged from 0.038 to 0.825, and 29 highly polymorphic loci (PIC ≥ 0.5) and 42 moderately polymorphic loci (0.25 < PIC < 0.5) were identified. Thirty-eight of the 115 loci deviated significantly from the Hardy-Weinberg equilibrium (P < 0.01) after a Bonferroni correction. A BlastX search revealed that 46 (40%) of the polymorphic loci identified were from transcript regions of known genes. The microsatellite markers developed in the present study will greatly enrich the microsatellite resources of T. granosa, and are available for further population genetic analysis, genetic trait mapping, and molecular-assisted selection.

Microsatellite marker analysis reveals the distinction between the north and south groups of hard clam (Meretrix meretrix) in China

Meretrix meretrix is one of the important commercial bivalves in China. A total of 198 individual clams were collected from 5 locations characteristic of the clam's 5 main natural habitats in China, that is, Shandong, Jiangsu, Fujian, Guangdong, and Guangxi. Ten polymorphic microsatellite markers were selected to examine the genetic diversity and identify genetic differences between the 5 populations. A total of 183 alleles across 10 loci were detected in the individual clams. The observed heterozygosity and expected heterozygosity ranged from 0.197 to 0.7026 and from 0.6264 to 0.9408, respectively. The genetic diversity within samples was high (8.6-11.2 alleles per locus, observed heterozygosity = 0.25-0.875 and expected heterozygosity = 0.6848-0.9259). Most of the genotype distributions significantly deviated from Hardy-Weinberg equilibrium. Genetic structure analysis showed that the 5 populations could be divided into 2 groups, the north and south groups. Neighbor-joining analysis revealed a clear distinction between the north group (Shandong and Jiangsu) and the south group (Fujian, Guangdong, and Guangxi). Locus MM1031 was used to distinguish between groups. Our results can be used for population identification and crossbreeding of M. meretrix.

InGaN self-assembled quantum dots grown by metal-organic chemical vapour deposition with growth interruption

Self-assembled InGaN quantum dots (QDs) were grown by metal-organic chemical vapour deposition with growth interruption at low V/III ratio and low growth temperature on sapphire substrates. The effects of the interruption time on the morphological and optical properties of InGaN QDs were studied. The results show that the growth interruption can modify the dimension and distribution of InGaN QDs, and cause the QD emission wavelength to blue shift with increasing interruption time. A density of InGaN QDs of about 4.5 × 10(10) cm(-2) with an average lateral size of 11.5 nm and an average height of 1.6 nm can be obtained by using a growth interruption time of 60 s.

Chicken Granulosa Cells Show Differential Expression of Epidermal Growth Factor (EGF) and Luteinizing Hormone (LH) Receptor Messenger RNA and Differential Responsiveness to EGF and LH Dependent upon Location of Granulosa Cells to the Germinal Disc1

Granulosa cells in the chicken follicle exhibit different phenotypes according to their location relative to the germinal disc (GD). Granulosa cells proximal to the GD (referred to as proximal granulosa cells) are more proliferative, whereas granulosa cells distal to the GD (referred to as distal granulosa cells) are more differentiated. We have shown that epidermal growth factor (EGF) derived from the GD stimulated proliferation of granulosa cells proximal to the GD, whereas extraovarian LH promoted differentiation. We tested the hypothesis that phenotypic differences of granulosa cells are the result of differential responsiveness of granulosa cells to EGF and LH. We found that both granulosa and theca layers of chicken preovulatory follicles expressed mRNA for EGF receptor (EGFr) by polymerase chain reaction (PCR) analysis. However, only the granulosa layer showed differential expression of EGFr and LH receptor (LHr) mRNA. Competitive reverse transcription-PCR revealed that proximal granulosa cells expressed more EGFr mRNA but less LHr mRNA than distal granulosa cells. In addition, proximal granulosa cells proliferated more in response to EGF than their distal counterparts. We further demonstrated that EGF decreased LHr mRNA expression by granulosa cells in a dose-dependent manner, whereas EGF and LH had no effect on EGFr mRNA expression except at one dose of LH (15 ng/ml) that stimulated EGFr mRNA expression. Our findings suggest that EGF derived from the GD influences the phenotypes of granulosa cells. Granulosa cells proximal to the GD exhibit a proliferative phenotype possibly because they are exposed to and are more responsive to GD-derived EGF. Furthermore, GD-derived EGF decreases LHr mRNA expression by proximal granulosa cells and therefore results in less differentiated granulosa cell phenotype. In contrast, granulosa cells distal to the GD are not under the influence of EGF and exhibit a more differentiated phenotype.

Germinal disc-derived epidermal growth factor: a paracrine factor to stimulate proliferation of granulosa cells

The germinal disc (GD) of the chicken oocyte produces factors that influence proliferation and differentiation of granulosa cells. Granulosa cells proximal to the GD are more proliferative, whereas granulosa cells distal to the GD are more differentiated. Previously, we had found epidermal growth factor (EGF) was present in the GD. In this study, we tested the hypothesis that EGF is the GD-derived paracrine factor that stimulates proliferation of granulosa cells. Northern analysis, reverse transcription-polymerase chain reaction, and radioimmunoassay indicated that the GD and granulosa cells but not theca cells are the sources of EGF in chicken preovulatory follicles. However, only the conditioned medium from the GD region (GDR = GD + overlying granulosa cells) but not the granulosa cell-conditioned medium stimulated proliferation of granulosa cells. Pretreatment of conditioned media with EGF antibody abolished the proliferation-stimulating effect of the GDR-conditioned medium. We conclude that EGF is one of the paracrine factors produced by the GD to stimulate proliferation of granulosa cells. Granulosa cells proximal to the GD express a proliferative phenotype possibly because they are exposed to a greater amount of EGF derived from the GD.

Simultaneous determination of ethylene glycol and glycolic acid in serum by gas chromatography-mass spectrometry

We describe a gas chromatographic-mass spectrometric (GC-MS) procedure for the simultaneous determination of ethylene glycol (EG) and its major toxic metabolite, glycolic acid (GA), in serum. In this method, serum (50 microL) is treated with 150 microL of glacial acetic acid/acetonitrile (1:10, v/v; contains internal standard, 1,3-propanediol, 15 mg/dL) to precipitate protein. After centrifugation, 10 microL of supernate is treated with 500 microL of 2,2-dimethoxypropane/dimethylformamide (80:20, v/v) to convert water to methanol, and the volume is then reduced to < 100 microL of dimethylformamide (but not to dryness). After formation of tertbutyldimethylsilyl derivatives, analysis is performed by capillary column GC-MS in selected ion mode. The method gives a linear response to 1000 mg/L each EG and GA (16.1 mmol/L and 13.2 mmol/L, respectively) and has a lower limit of detection and a lower limit of quantitation of 10 mg/L each EG and GA (0.16 mmol/L and 0.13 mmol/L, respectively). Total assay imprecision is CV < or = 6.4% (200 and 800 mg/L EG and GA [3.2 and 12.9 mmol/L EG; 2.6 and 10.5 mmol/L GA, respectively]). Absolute recovery from human serum was 91.1% for EG and 77.6% for GA. The procedure is free from any known interference. A complete analysis set (three calibrators, patient serum neat, patient serum diluted 1:5 (v/v), and two controls) may be completed in about 2 h. A preliminary result, based on a single calibrator and patient serum diluted 1:5 (v/v), is complete in about 1 h. The method has been used to aid the diagnosis and management in 34 cases of EG intoxication. Selected cases are briefly reviewed.

Restricted expression of WT1 messenger ribonucleic acid in immature ovarian follicles: uniformity in mammalian and avian species and maintenance during reproductive senescence

WT1 is a zinc finger protein with transcriptional repressor activity on several growth factor and growth factor receptor genes. In the ovary, a potential role for WT1 in the suppression of the development of immature follicles has been demonstrated. Here, gel retardation assays further showed that recombinant WT1 protein interacted with consensus DNA sequences in the inhibin-alpha gene promoter. We investigated the pattern of WT1 expression in a wide variety of species and also over the reproductive life span in rats. In chicken ovaries, Northern blot analysis revealed the presence of WT1 transcript in small healthy white follicles (1-5 mm in diameter) and its absence in small yellow (6-12 mm in diameter) or larger follicles (F1-F5). In pig and monkey ovaries, WT1 expression was limited to granulosa cells of preantral follicles, as shown by in situ hybridization analysis. In rats, Northern blot analyses demonstrated the presence of WT1 transcript in the ovaries of young (3-mo-old) and middle-aged (9-mo-old) rats on the proestrous day, with a decrease in old (12-mo-old) rats in persistent estrus. In situ hybridization analysis further suggested that the decrease in WT1 expression in aging ovaries was associated with fewer immature follicles. Thus, WT1 expression is restricted to immature follicles in diverse avian and mammalian species and over the reproductive life span in rats. These data demonstrated that WT1 is a marker for immature follicles and suggested a potential role of this transcriptional repressor in the slow growth of early follicles.

Destruction of the germinal disc region of an immature preovulatory chicken follicle induces atresia and apoptosis

The germinal disc region (GDR), which contains the germinal disc and overlying granulosa cells, is essential for completion of maturation of the preovulatory chicken follicle. The current study was conducted to test the hypothesis that destruction of the GDR (GDRX) of an immature preovulatory chicken follicle blocks ovulation, induces apoptosis, and causes atresia. The GDR of immature preovulatory follicles (F2) were destroyed by freezing with dry ice (3 mm in diameter) 48-50 h before ovulation. As a control for the effect of freezing, a nonGDR portion (a portion of the follicular wall opposite to the GDR relative to the follicular stalk) of other F2 follicles were destroyed (nonGDRX). Treatment of F2 follicles by GDRX caused atresia and blocked ovulation of all treated follicles (6 of 6), whereas none of the nonGDRX follicles (0 of 5) underwent atresia. Treatment of follicles by GDRX induced apoptotic DNA fragmentation (laddering) in theca and granulosa layers obtained from the frozen area and in the theca layer obtained from the follicular wall distal to the frozen area. In contrast, apoptosis was only present in theca and granulosa layers in the frozen area of the nonGDRX follicle. Furthermore, the in situ DNA end-labeling technique demonstrated that in the GDRX follicle 24 h after treatment, cells in the theca interna, endothelial cells in blood vessels of the theca externa, and a few granulosa cells underwent apoptosis. These results indicate that destruction of the GDR of an immature preovulatory follicle causes atresia and apoptosis and blocks ovulation. These novel findings suggest that the GDR maintains development of the chicken preovulatory follicle by producing one or more survival factors. Without the GDR, chicken follicles cannot develop further and they eventually die.

Epidermal growth factor in the germinal disc and its potential role in follicular development in the chicken

The germinal disc region (GDR; germinal disc + overlying granulosa cells) of the hen's ovarian follicle secretes one or more factors that stimulate proliferation of, and decrease progesterone (P4) production by, granulosa cells. Destruction of the GDR results in apoptosis and atresia of the follicle. These data suggested that the GDR produces a growth factor(s) to sustain the development of the follicle. These findings prompted us to investigate two questions: 1) Is epidermal growth factor (EGF) or transforming growth factor alpha (TGFalpha), which binds to the EGF receptor, present in the GDR? 2) Does EGF regulate granulosa cell functions in the hen? Immunocytochemistry revealed that EGF, but not TGFalpha, was present in the germinal disc of the four largest preovulatory follicles of the hen. TGFalpha was found only in the theca interna. To determine whether EGF regulates granulosa cell functions, granulosa layer explants (13 mm in diameter) from the second-largest preovulatory follicle were cultured for 36 h with 0,0.017, or 0.17 microM EGF. Proliferation, apoptosis, and P4 production of granulosa layer explants were then measured by using a colorimetric method for determining viable cell number, gel electrophoresis, and RIA, respectively. EGF regulates several functions of granulosa layer explants by stimulating proliferation, inhibiting apoptosis, and decreasing basal P4 production. These data indicate that EGF is present in the germinal disc and may be one of the factors that regulate follicular development in the hen.

Laboratory and clinical evaluation of assays for beta-hydroxybutyrate

We have performed a two-part evaluation of assays for beta-hydroxybutyrate (beta HB). In Part I, we evaluated the analytical acceptability of a dry film, self-contained analyzer for beta HB measurement (KetoSite; GDS Diagnostics, Elkhart, Ind). The assay response is linear and between-day imprecision is acceptable. Acetoacetate (AcAc) interferes severely with this assay. This interference could be minimized by dilution of serum before the assay. With this predilution protocol, KetoSite beta HB results compare favorably with an automated Sigma (St. Louis, Mo) beta HB assay. In Part II, we compared the clinical utility of beta HB measurements (Sigma) with the qualitative measurement of ketones using the nitroprusside test (Acetest; Bayer, Elkhart, Ind) for the diagnosis and management of diabetic ketoacidosis (DKA). Test results for both assays were abnormal for all patients with DKA on admission. However, frequent monitoring with either test during the management of uncomplicated DKA added little if any additional clinical information over routine measurements of serum glucose and total carbon dioxide.

Simultaneous determination of ethylene glycol and its major toxic metabolite, glycolic acid, in serum by gas chromatography

We developed a gas-chromatographic procedure for the simultaneous determination of ethylene glycol (EG) and its major toxic metabolite, glycolic acid (GA), suitable for clinical use in instances of EG intoxication. After serum protein precipitation with acetonitrile (containing internal standard), the supernate is treated with 2,2-dimethoxypropane (containing dimethylformamide) to remove water, and the volume is then reduced by evaporation to &lt;100 microL of dimethylformamide (but not to dryness). After trimethylsilyl derivatization, the resulting derivatives are analyzed by capillary column gas chromatography. Only 100 microL of serum is required and the entire determination, including calibrators and controls, takes &lt;2 h. The method gives a linear response to at least 10 g/L EG and 5 g/L GA and has a limit of detection &lt;10 mg/L. Intraassay CV is &lt; or = 2.8% for EG (100 and 1000 mg/L) and GA (100 and 500 mg/L); between-day CV is &lt; or = 6.5%. The absolute recovery from serum was 91% for EG and 77-82% for GA (200 and 2000 mg/L each). Relative to calibrators prepared bovine serum albumin (70 g/L), the recovery was 99-104% for EG (100 - 5000 mg/L) and 95-105% for GA (50 - 2500 mg/L). No clinically important interference was detected for &gt;60 exogenous or endogenous compounds and drugs.

Simultaneous determination of ethylene glycol and its major toxic metabolite, glycolic acid, in serum by gas chromatography

We developed a gas-chromatographic procedure for the simultaneous determination of ethylene glycol (EG) and its major toxic metabolite, glycolic acid (GA), suitable for clinical use in instances of EG intoxication. After serum protein precipitation with acetonitrile (containing internal standard), the supernate is treated with 2,2-dimethoxypropane (containing dimethylformamide) to remove water, and the volume is then reduced by evaporation to <100 microL of dimethylformamide (but not to dryness). After trimethylsilyl derivatization, the resulting derivatives are analyzed by capillary column gas chromatography. Only 100 microL of serum is required and the entire determination, including calibrators and controls, takes <2 h. The method gives a linear response to at least 10 g/L EG and 5 g/L GA and has a limit of detection <10 mg/L. Intraassay CV is < or = 2.8% for EG (100 and 1000 mg/L) and GA (100 and 500 mg/L); between-day CV is < or = 6.5%. The absolute recovery from serum was 91% for EG and 77-82% for GA (200 and 2000 mg/L each). Relative to calibrators prepared bovine serum albumin (70 g/L), the recovery was 99-104% for EG (100 - 5000 mg/L) and 95-105% for GA (50 - 2500 mg/L). No clinically important interference was detected for >60 exogenous or endogenous compounds and drugs.

Extended relational operators for statistical data manipulations in medical databases

Conventional relational database management systems fail to address three features of statistical data management in a biomedical/clinical database, namely, that (1) statistical and medical data (SMD) require a great deal of space and need to be stored in a reduced form with minimal duplication; indeed, SMD have many derived/calculated and summary statistics that make the number of attributes in a relation (i.e., a set of records) grow rapidly and dynamically; (2) most SMD have hierarchical structures that are difficult to manage using the relational data model since SMD are stored in separate relations for duplication and space considerations; and (3) the management of SMD is made easier if it is possible to reorganize relations or group data, a capability lacking in conventional relational database management systems. In this paper, we (1) introduce five extended relational operators, (lattice) NEST, (lattice) UNNEST, MERGE, SPREAD, and GEN, to reorganize relations; (2) integrate the extended operators with conventional relational algebra and introduce the concept of the lattice relational model; and (3) give applications of the extended relational operators and the lattice relational model in solving the problems of statistical data manipulation in medical databases.

Numerical study of radially inhomogeneous optical fibers using a predictor-corrector method

The predictor-corrector method is used for the numerical integration of Maxwell's equations for radially inhomogeneous fiber problems. Its accuracy and efficiency compare favorably with the Runge-Kutta and collocation methods used previously. Its practical application is illustrated by its use to study the effects on the propagation characteristics produced by a central dip and a valley between the core and cladding in the index profile of a radially inhomogeneous fiber, normally having (a) parabolic core and a finite cladding. The departures of these propagation characteristics from those of the regular fiber with a parabolic index are pointed out.