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91.
Listeria monocytogenes (LM) preferentially colonizes the placenta and causes fetal loss and systemic disease during pregnancy. As systemic CD8+ T-cell memory is critical in controlling LM infection, we addressed the issue as to whether it is modulated during pregnancy.

Method of study


Pregnant mice were infected with LM and their immune response was quantified relative to the non-pregnant cohort using advanced immunological techniques.

Results


Pregnant mice exhibited progressive and massive placental LM infection leading to fetal resorptions. In contrast, they harbored significantly lower bacteria in spleen and liver relative to non-pregnant controls, and rapidly cleared systemic infection. Both pregnant and non-pregnant mice exhibited similar activation of systemic innate immunity. Moreover, LM infection in pregnant and non-pregnant hosts evoked strong antigen-specific cytolytic CD8+ T cells that produced IFN-γ. Consequently, LM infection initiated during pregnancy afforded long-term protective memory to secondary infection.

Conclusion


Maternal hosts generate a normal Listeria -specific adaptive immunity in particular CD8+ T-cell memory response suggesting that systemic listeriosis during pregnancy may be an immunopathology associated with placental infection.  相似文献   
92.
OBJECTIVE: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the use of a lower concentration (0.5 M). A higher concentration would also cause a reduction in dose. The purpose of our study was to test the use of a low dose (0.05 mmol/kg) of gadobutrol in magnetic resonance renography and angiography and compare the findings with a dose of 0.1 mmol/kg. MATERIALS AND METHODS: One-hundred-thirty-four patients referred for magnetic resonance angiography for suspected renovascular disease participated in the study. Contrast enhanced MR renography and angiography were performed after administration of a bolus of 0.1 mmol/kg or 0.05 mmol/kg gadobutrol in randomized patients. The relative signal intensity-time curves of the aorta, peripheral cortex and parenchyma, were obtained. Two radiologists evaluated the angiographic images and evaluated the quality of angiography. RESULTS: The signal intensity with a low dose of gadobutrol was significantly lower in early phases, in the peripheral cortex (for 36, 54, 72 and 90 seconds), the parenchyma (for 36, 54, 72 seconds) and the aorta (for 18, 36, 54, 72 seconds). The decreases in the early phase obtained with a low dose of gadobutrol caused blunter time intensity curves. The difference in the quality scores of the readers for the angiographic images for the use of the two different doses was not statistically significant (p > 0.05). CONCLUSION: A lower dose of gadobutrol can be used for MR renal angiography, but for MR renography the normal dose should be used.  相似文献   
93.
Clinical, radiographic, and operative findings in two children with intra-osseous pseudomeningocele of the occipital bone due to cranial trauma are presented here, along with a literature review of this uncommon radiologic entity.  相似文献   
94.
INTRODUCTION: The aims of this study were to determine the size of individual permanent teeth, tooth-size ratios for the maxillary and mandibular dentitions, and sex differences for those variables in a Turkish population, and to compare the figures obtained with those of the Bolton analysis. METHODS: The data were derived from dental casts of 150 Turkish subjects (72 men, mean age 22.09 +/- 3.11 years; 78 women, mean age, 21.11 +/- 2.08 years) with normal occlusions. The mean, standard deviation, and minimum and maximum values were calculated for individual tooth size, and overall and anterior ratios, separately for men and women. To determine whether there are sex differences in intermaxillary tooth size discrepancies, an independent samples t test was performed. RESULTS: The mesiodistal dimensions of the maxillary teeth showed greater variability than the mandibular teeth, with the first molar dimensions having the greatest variability. The overall and anterior ratios were found to be 89.88 +/- 2.29 and 78.26 +/- 2.61, respectively. A statistically significant sex difference was found only in overall ratio (P < .001). According to Bolton's mean values, a discrepancy in the overall ratio was found in 18% of Turkish normal occlusion subjects, and anterior ratios outside 2 standard deviations from the Bolton mean were found in 21.3% of our sample. CONCLUSIONS: These findings indicate that population-specific standards are necessary for clinical assessments. Bolton's original data do not represent Turkish people, and therefore it is appropriate to use Turkish norms in daily orthodontic practice for Turkish patients.  相似文献   
95.
Neopterin is an immunological marker of cellular immune activation. Etanercept is a tumor necrosis factor-α (TNF-α) antagonist that decreases excessive levels of TNF-α associated with inflammatory disease down to physiological levels. The objective of this study was to investigate urine neopterin levels in psoriatic patients treated with etanercept, to study the effect of etanercept as a TNF-α blocker on urine neopterin levels. Urine neopterin levels and urine neopterin/creatinine ratios were measured by high-performance liquid chromatography in 22 patients with psoriasis before and after treatment with etanercept. Results were compared with a group of 20 healthy volunteers, and 20 patients with inflammatory skin diseases as control groups. Urine neopterin levels, neopterin/creatinine ratios and Psoriasis Area and Severity Index (PASI) scores were evaluated at baseline, and the 12th and 24th week after treatment. Urine neopterin levels were significantly elevated in the psoriatic group compared with control and inflammatory skin diseases groups ( P  < 0.05). Urine neopterin levels were significantly reduced after etanercept treatment. Statistically we did not find any correlation between neopterin levels and PASI scores. Our findings indicate that urine neopterin concentrations may reflect the disease activity in psoriasis, and may be used as a marker for monitoring disease activity and response to treatment with etanercept in psoriatic patients.  相似文献   
96.

Purpose

To develop a novel automated method for segmentation of the injured spleen using morphological properties following abdominal trauma. Average attenuation of a normal spleen in computed tomography (CT) does not vary significantly between subjects. However, in the case of solid organ injury, the shape and attenuation of the spleen on CT may vary depending on the time and severity of the injury. Timely assessment of the severity and extent of the injury is of vital importance in the setting of trauma.

Methods

We developed an automated computer-aided method for segmenting the injured spleen from CT scans of patients who had splenectomy due to abdominal trauma. We used ten subjects to train our computer-aided diagnosis (CAD) method. To validate the CAD method, we used twenty subjects in our testing group. Probabilistic atlases of the spleens were created using manually segmented data from ten CT scans. The organ location was modeled based on the position of the spleen with respect to the left side of the spine followed by the extraction of shape features. We performed the spleen segmentation in three steps. First, we created a mask of the spleen, and then we used this mask to segment the spleen. The third and final step was the estimation of the spleen edges in the presence of an injury such as laceration or hematoma.

Results

The traumatized spleens were segmented with a high degree of agreement with the radiologist-drawn contours. The spleen quantification led to \(86\pm 5\,\%\) volume overlap, \(92.5\pm 3.11\,\%\) Dice similarity index, \(89.05\pm 5.29\,\%/96.42\pm 2.55\) precision/sensitivity, \(8\pm 5\,\%\) volume estimation error rate, \(1.09\pm 0.62/1.91\pm 1.45\,\hbox {mm}\) average surface distance/root-mean-squared error.

Conclusions

Our CAD method robustly segments the spleen in the presence of morphological changes such as laceration, contusion, pseudoaneurysm, active bleeding, periorgan and parenchymal hematoma, including subcapsular hematoma due to abdominal trauma. CAD of the splenic injury due to abdominal trauma can assist in rapid diagnosis and assessment and guide clinical management. Our segmentation method is a general framework that can be adapted to segment other injured solid abdominal organs.
  相似文献   
97.

Introduction  

The purpose of the present study was to evaluate the effects of intravenous lornoxicam on haemodynamic and biochemical parameters, serum cytokine levels and patient outcomes in severe sepsis.  相似文献   
98.
99.

Introduction  

The purpose of the present study was to evaluate the effects of continuously infused N-acetyl-L-cystein (NAC) on serum cytokine levels and gastric intramucosal pH in humans suffering from severe sepsis.  相似文献   
100.
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