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Chi-square P (chi-square + p)
Selected AbstractsMapping markers linked to porcine salmonellosis susceptibilityANIMAL GENETICS, Issue 6 2009L. Galina-Pantoja Summary The goal of this study was to identify pig chromosomal regions associated with susceptibility to salmonellosis. Genomic DNA from pig reference populations with differences in susceptibility to Salmonella enterica serovar Choleraesuis as quantified by spleen and liver bacterial colonization at day 7 post-infection (dpi; Van Diemen et al. 2002) was used. These samples belonged to the offspring of a sire thought to be heterozygous for genes involved in susceptibility to salmonellosis. Amplified fragment length polymorphism (AFLP) markers were created and used to determine associations with spleen or bacterial counts at 7 dpi. To position linked markers, two mapping populations, the Roslin and Uppsala PiGMaP pedigrees were used to create an integrated map which included the AFLP markers associated with salmonellosis. Twenty-six AFLP markers located in 14 different chromosomal regions in the porcine genome were found to be significantly associated with susceptibility (Chi-square P < 0.05). More than one linked marker was found on chromosomes 1, 7, 13, 14 and 18. It is likely that these regions contain genes involved in Salmonella susceptibility. Regions on chromosomes 1, 7 and 14 were significantly associated with Salmonella counts in the liver and regions on chromosomes 11, 13 and 18 with counts in spleen. The identification of these chromosomal regions highlights specific areas to search for candidate genes that may be involved in innate or adaptive immunity. Further investigation into these chromosomal regions would be useful to improve our understanding of host responses to infection with this widespread pathogen. [source] Increased detection of HBV DNA in HBsAg-positive and HBsAg-negative South African HIV/AIDS patients enrolling for highly active antiretroviral therapy at a Tertiary HospitalJOURNAL OF MEDICAL VIROLOGY, Issue 3 2009Azwidowi Lukhwareni Abstract This retrospective study investigated the prevalence of hepatitis B virus (HBV) in 192 stored sera from human immunodeficiency virus (HIV) positive South African patients initiating antiretroviral therapy (ART), and explored the implications of HBV,HIV co-infection on laboratory diagnosis of HBV. HBV serology (HBsAg, anti-HBs and anti-HBc) and nested HBV PCR assays targeting the HBV polymerase gene were performed, with HBV DNA positive samples being quantified with Cobas Taqman HBV test 48 assay (Roche Diagnostics). The study found that 63% (121/192) of patients had past or present HBV infection, and 40.6% (78/192) had detectable HBV DNA. Also, 22.9% (44/192) of patients were HBsAg positive and HBV DNA positive, while 23% (34/148) of HBsAG negatives had occult HBV infections. Of the 78 HBV DNA positive samples, 62.8% had viral loads ranging from 102 to ,108 IU/ml, and 37.2% had HBV viral loads <200 IU/ml. There was a statistically significant positive association between HBsAg-positivity and high viral loads, with 27% (12/44) of HBsAg positives having HBV viral loads between 104 and ,108 IU/ml, compared to only 5.9% (2/34) of HBsAg negatives (relative risk: 4.64; 95% confidence interval: 1.11, 19.35; chi-square P -value,=,0.015). The study shows that the majority of HIV/AIDS patients initiating ART have either acute or chronic HBV infections, and further confirms that HIV remains a risk factor for occult HBV infections in South African patients as previously shown. The findings strongly support HBV screening in all HIV-positive patients initiating ART in South Africa, considering that current ART regimens include drugs with anti-HBV activity (e.g., lamivudine). J. Med. Virol. 81:406,412, 2009. © 2009 Wiley-Liss, Inc. [source] Does the panel of cytokeratin 20 and androgen receptor antibodies differentiate desmoplastic trichoepithelioma from morpheaform/infiltrative basal cell carcinoma?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 2 2008Terrence M. Katona Background:, Evaluation of androgen receptor (AR) and cytokeratin 20 (CK20) expression can aid in distinguishing between conventional basal cell carcinoma (characteristically AR+, CK20,) and trichoepithelioma (frequently AR,, CK20+). Within these two groups of tumors, morpheaform/infiltrative basal cell carcinoma (mBCC) and desmoplastic trichoepithelioma (DTE) are particularly challenging to differentiate both clinically and histologically. We investigated whether AR and CK20 immunostains may distinguish between mBCC and DTE. Methods:, Immunohistochemistry for AR and CK20 was performed on 15 DTEs and 31 mBCCs. Any immunoreactivity within the tumor for AR or CK20 was considered positive. Results:, AR expression was seen in 13% (2/15) of DTE and 65% (20/31) of mBCC cases (chi-square p = 0.0011). CK20-positive Mėrkel cells were identified in 100% (15/15) of DTE and 3% (1/31) of mBCC (chi-square p < 0.0001). The expected pattern of AR,, CK20+ immunophenotype was present in 87% (13/15) of DTE cases. In mBCC, 61% (19/31) was AR+, CK20,. No DTE was AR+, CK20, and no mBCC was AR,, CK20+. Conclusions:, Immunohistochemical stains for AR and CK20 are useful to differentiate DTE from mBCC. The AR,, CK20+ immunophenotype is sensitive (87%) and specific for DTE (100%). The AR+, CK20, immunophenotype is specific (100%) and moderately sensitive (61%) for mBCC. [source] CT15 RISK STRATIFICATION MODELS FOR HEART VALVE SURGERYANZ JOURNAL OF SURGERY, Issue 2007C. H. Yap Purpose Risk stratification models may be useful in aiding surgical decision-making, preoperative informed consent, quality assurance and healthcare management. While several overseas models exist, no model has been well-validated for use in Australia. We aimed to assess the performance of two valve surgery risk stratification models in an Australian patient cohort. Method The Society of Cardiothoracic Surgeons of Great Britain and Ireland (SCTS) and Northern New England (NNE) models were applied to all patients undergoing valvular heart surgery at St Vincent's Hospital Melbourne and The Geelong Hospital between June 2001 and November 2006. Observed and predicted early mortalities were compared using the chi-square test. Model discrimination was assessed by the area under the receiver operating characteristic (ROC) curve. Model calibration was tested by applying the chi-square test to risk tertiles. Results SCTS model (n = 1095) performed well. Observed mortality was 4.84%, expected mortality 6.64% (chi-square p = 0.20). Model discrimination (area under ROC curve 0.835) and calibration was good (chi-square p = 0.9). the NNE model (n = 1015) over-predicted mortality. Observed mortality 4.83% and expected 7.54% (chi-square p < 0.02). Model discrimination (area under ROC curve 0.835) and calibration was good (chi-square p = 0.9). Conclusion Both models showed good model discrimination and calibration. The NNE model over-predicted early mortality whilst the SCTS model performed well in our cohort of patients. The SCTS model may be useful for use in Australia for risk stratification. [source] | |||||||||||||