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91.
A Fukui EI Ntrivalas A Gilman-Sachs J Kwak-Kim KD Beaman 《American journal of reproductive immunology (New York, N.Y. : 1989)》2006,55(6):395-395
Aim: To determine if IgA is required for protection against Chlamydia infection in the male reproductive tract (MRT).
Materials and Methods: Male polyimmunoglobulin receptor knockout mice (PIgR-/- ) and wild-type C57BL/6 (WT) mice were immunised intranasally with chlamydial major outer membrane protein (MOMP) and cholera toxin (CT). MOMP-specific IgG and IgA in serum and prostatic fluids were measured by ELISA. Serum and PF were also assayed for inhibition of in vitro chlamydial infection. Immunized WT and PIgR-/- mice were challenged by direct inoculation of C. muridarum into the meatus urethra. Four weeks post challenge Chlamydia levels in the penile urethra, epididymis and testis were determined by PCR.
Results: Equivalent levels of IgG were found in the serum of both WT and PIgR-/- mice however IgA in serum of PIgR-/- mice was 19- to 20-fold higher than in WT animals consistent with the lack of the PIgR IgA transport molecule. IgA levels were significantly lower in PIgR-/- PF compared to WT PF after both immunization and infection. Only PF from WT but not PIgR-/- animals was able to inhibit in vitro chlamydial infection. Following challenge significantly higher levels of Chlamydia were recovered from the MRT of PIgR-/- mice compared to WT animals.
Conclusions: Male mice lacking a functional PIgR were unable to clear a genital tract Chlamydia infection despite high levels of serum IgA. These data show that mucosal IgA plays a major role in preventing chlamydial infection of the male genital tract and suggest that immunization strategies to protect males should target a strong mucosal IgA response. 相似文献
Materials and Methods: Male polyimmunoglobulin receptor knockout mice (PIgR
Results: Equivalent levels of IgG were found in the serum of both WT and PIgR
Conclusions: Male mice lacking a functional PIgR were unable to clear a genital tract Chlamydia infection despite high levels of serum IgA. These data show that mucosal IgA plays a major role in preventing chlamydial infection of the male genital tract and suggest that immunization strategies to protect males should target a strong mucosal IgA response. 相似文献
92.
E Hyde 《Journal of nurse-midwifery》1989,34(4):171-178
A prospective, controlled clinical trial examined the efficacy of acupressure therapy for morning sickness, using a two group, random assignment, crossover design. Subjects in Group 1 (N = 8) used acupressure wristbands for five days, followed by five days without therapy. Subjects in Group 2 (N = 8) had no therapy for five days, followed by five days use of wristbands. The Multiple Affect Adjective Checklist and Sickness Impact Profile were used, and extent of nausea was assessed at baseline, day five, and day ten. Use of acupressure wristbands relieved morning sickness for 12 of 16 subjects (chi 2 = 5.31 with Yates' correction factor, df = 1, p less than .025). Acupressure therapy resulted in statistically significant (p less than .05) reductions in anxiety, depression, behavioral dysfunction, and nausea. Limitations of the study and suggestions for future research are presented. 相似文献
93.
Archives of Dermatological Research - 相似文献
94.
Hyde A Fontaine D Stuckless S Green R Pollett A Simms M Sipahimalani P Parfrey P Younghusband B 《The American journal of surgical pathology》2010,34(12):1820-1829
Identifying colorectal cancers (CRCs) with high levels of microsatellite instability (MSI-H) is clinically important. MSI-H is a positive prognostic marker for CRC, a predictive marker for resistance to standard 5-fluorouracil-based adjuvant chemotherapy, and an important feature for identifying individuals and families with Lynch syndrome. Our aim was to compare and improve upon the existing predictive pathology models for MSI-H CRCs. We tested 2 existing models used to predict MSI-H tumors, (1) Revised Bethesda Guidelines and (2) MsPath, in our population-based cohort of CRCs diagnosed less than 75 years from Newfoundland (N=710). We also scored additional histologic features not described in the other models. From this analysis, we developed a model for the prediction of MSI-H CRCs; Pathologic Role in Determination of Instability in Colorectal Tumors (PREDICT). An independent pathologist validated this model in a second cohort of all CRCs (N=276). Tumor histology was a better predictor of MSI status than was personal and family history of cancer. MsPath identified MSI-H CRCs with a sensitivity of 92.1% and a specificity of 37.8%, whereas the Revised Bethesda Guidelines had a sensitivity of 81.3% and a specificity of 39.5%. PREDICT included some new histology features, including peritumoral lymphocytic reaction and increased proportion of plasma cells in the tumor stroma. PREDICT was superior to both existing models in the development cohort with a sensitivity of 97.4% and a specificity of 53.9%. In the validation cohort, sensitivity was 96.9% and specificity 76.6%. We conclude that PREDICT is a good predictor of MSI-H CRC. 相似文献
95.
William C Kreisl Kimberly J Jenko Christina S Hines Chul Hyoung Lyoo Winston Corona Cheryl L Morse Sami S Zoghbi Thomas Hyde Joel E Kleinman Victor W Pike Francis J McMahon Robert B Innis the Biomarkers Consortium PET Radioligand Project Team 《Journal of cerebral blood flow and metabolism》2013,33(1):53-58
Second-generation radioligands for translocator protein (TSPO), an inflammation marker, are confounded by the codominant rs6971 polymorphism that affects binding affinity. The resulting three groups are homozygous for high-affinity state (HH), homozygous for low-affinity state (LL), or heterozygous (HL). We tested if in vitro binding to leukocytes distinguished TSPO genotypes and if genotype could affect clinical studies using the TSPO radioligand [11C]PBR28. In vitro binding to leukocytes and [11C]PBR28 brain imaging were performed in 27 human subjects with known TSPO genotype. Specific [3H]PBR28 binding was measured in prefrontal cortex of 45 schizophrenia patients and 47 controls. Leukocyte binding to PBR28 predicted genotype in all subjects. Brain uptake was ∼40% higher in HH than HL subjects. Specific [3H]PBR28 binding in LL controls was negligible, while HH controls had ∼80% higher binding than HL controls. After excluding LL subjects, specific binding was 16% greater in schizophrenia patients than controls. This difference was insignificant by itself (P=0.085), but was significant after correcting for TSPO genotype (P=0.011). Our results show that TSPO genotype influences PBR28 binding in vitro and in vivo. Correcting for this genotype increased statistical power in our postmortem study and is recommended for in vivo positron emission tomography studies. 相似文献
96.
The influence of clavicipitaceous fungal endophytes on grass decomposition rates has been studied through field and laboratory experiments. However, the effects of endophytes on decomposition rates of non-grass species are unclear. This paper reviews research data related to the effects of fungal endophytes on decomposition rates of three litter types: grass, non-grass leaf litter (including spruce needle litter) and non-grass twigs and wood. We discuss how fungal endophytes are involved in, or regulate decomposition rates and may change lifestyles from fungal endophytes to saprotrophs. Classical morphology and molecular approaches together with digestion enzyme studies provide evidence to suggest that some endophyte species switch their ecological roles and adopt a new life style as saprotrophs. We also explore the main mechanisms that explain how fungal endophytes may decelerate decomposition rates and whether it is directly driven by alkaloids. Further research on the role of fungal endophytes in decomposition rates of both grass and non-grass litter is needed, especially those addressing the direct and indirect mechanisms by which endophytes affect decomposition rates. 相似文献
97.
ObjectiveTo determine the prevalence of Trichomonas vaginalis (T. vaginalis) in HIV/AIDS patients attending two different hospitals in southeast Nigeria.MethodsWe collected 970 urine samples from HIV/AIDS patients attending two different hospitals in southeast Nigeria. Samples were processed by microscopy and cultural methods.ResultsOut of the 970 screened, 355 (36.60%) were positive for T. vaginalis. Subjects with the least CD4+ count in the range of 40-140 cells/mL had the highest number of positive samples (180, 50.70%), while those in the range of 480-580 cells/mL had the least value (2, 0.56%). Those in the rural areas had a higher number of positive samples (155, 38.75%) than their urban counterparts (200, 35.09%) with respect to the total number examined in each group but this was not statistically significant (P>0.05). Out of the 355 positive cases, the university undergraduate students’ group had the highest percentage incidence of 53.00% followed by the low-income group with 47.08%.ConclusionsIt can be concluded that the occurrence of T. vaginalis increases with decrease in the CD4+ counts in HIV/AIDS patients in Nigeria. Since T. vaginalis may be an important cofactor in promoting the spread of HIV and, in some circumstances, may have a major impact on the epidemic dynamics of HIV, there is a need to take measures to check the spread of this parasitic infection. 相似文献
98.
99.
This technique provides a simple and reliable means of obtaining an operative arteriogram after carotid endarterectomy. Detection of unsuspected abnormalities before the wound is closed allows the surgeon to correct any abnormalities immediately with hopes of decreasing the incidence of postoperative neurological deficits. 相似文献
100.
The retinal degeneration B (RdgB) protein family is characterized by an amino-terminal phosphatidylinositol transfer protein (PITP) domain, several hydrophobic domains, and a highly conserved carboxyl terminus. We identified a zebrafish RdgB homolog (pl-RdgB) that lacks the amino-terminal PITP domain, while retaining over 45% amino acid identity with the two mouse RdgB proteins (M-RdgB1 and M-RdgB2). Unlike the widespread retinal expression observed for other vertebrate RdgB homologs, pl-RdgB is restricted in the retina to the cone cell inner segments. The pl-RdgB protein is also expressed in the brain, although its distribution is different than the other RdgB homologs. Analogous to M-RdgB2, pl-RdgB protein is extracted from a retinal homogenate by guanidine and not by Triton X-100. Thus, pl-RdgB and likely all the identified RdgB homologs are not integral membrane proteins, but may associate with the membrane through protein-protein interactions. While expression of either murine RdgB homolog restored the defective light response and prevented retinal degeneration in rdgB mutant flies, expressing zebrafish pl-RdgB in Drosophila rdgB2 null mutants slowed retinal degeneration without restoring the electrophysiological light response. Thus, pl-RdgB may define a previously unrecognized protein family, which includes the other RdgB homologs, that act through a protein complex to maintain photoreceptor viability. 相似文献