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61.
The role of fine-needle aspiration (FNA) cytology in the evaluation of thyroid lesions in not as well established in children when compared with adults. Hence we aimed to ascertain the utility and limitations of FNA in childhood thyroid lesions. This was a retrospective analysis of all thyroid FNA performed in children less than 14 years of age over a 4-year period (2005-2009). Histopathological follow-up was available in six cases. A total of 77 cases were included in the analysis. The most common cytological diagnosis was lymphocytic thyroiditis (49.3%), followed by colloid goiter (18.2%), hyperplasia (10.4%), and benign aspirate (7.8%); malignancy was identified in six cases (7.8%). Of these six cases, three were papillary thyroid carcinoma. There was one false-positive case reported as a Hurthle-cell neoplasm, which on histology showed Hashimoto's thyroiditis. One case each of rhabdomyosarcoma and spindle epithelial tumor with thymus like differentiation was wrongly diagnosed as thyroid neoplasm, NOS, and medullary carcinoma (spindle variant), respectively. The overall diagnostic accuracy was 98.6% with 100% sensitivity, 98.6% specificity, 80% positive predictive value, and 100% negative predictive value. FNA is extremely valuable in the initial evaluation of thyroid swelling in children. Rare neoplasms masquerading as thyroid nodules in children can pose difficulties in diagnosis; however, papillary carcinoma is easily recognized. In lymphocytic thyroiditis, it provides a tissue diagnosis, thereby avoiding more invasive procedure for merely diagnostic purposes.  相似文献   
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63.
IntroductionFetal hydrops is a serious condition which has high morbidity and mortality. Incidences of immune hydrops have decreased by manifold after introduction of anti-D immunoglobulin. Intra-uterine fetal blood transfusion revolutionized the treatment of these affected fetuses after diagnosis of immune fetal hydrops. In this study we aim to evaluate the clinical characteristics of immune hydropic fetuses and perinatal outcome after institution of intra-uterine transfusions. Materials and methodsA retrospective study was carried out in pregnant women with immune fetal hydrops from October 2004 to December 2019 in our tertiary care hospital. After diagnosis of fetal hydrops, all the fetuses received intra-uterine transfusions. All the newborns were followed up till 3 months postdelivery. All the fetuses were divided in two groups: hydrops diagnosed below 32 weeks (Group A) and in second group hydrops diagnosed after 32 weeks gestation (Group B). ResultsTotal 63 patients were diagnosed to have hydrops during the study period. Group A had 48 fetuses and Group B had 15 fetuses. Average gestational age of diagnosis of hydrops in group A was 24.2 weeks and in group B it was 32.5 weeks. All the fetuses received intra-vascular intra-uterine transfusion. Pericardial effusion was found to be significantly associated with group A. Successful perinatal outcome was seen in 92% fetuses. 87% fetuses had complete resolution of hydrops before delivery. All the fetuses received phototherapy and intra-venous immunoglobulin after delivery, and 5 fetuses underwent exchange transfusion. ConclusionFavourable perinatal outcome was achieved in hydropic fetuses with intra-uterine blood transfusions. Complete resolution of hydrops before delivery increases the chances of perinatal survival.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13224-020-01423-4.  相似文献   
64.
Prostanoids generated by COX-2 are involved in the regulation of inflammation but their exact role in the innate immune response has not been defined. We investigated whether COX-2 is involved in host defense against Pseudomonas aeruginosa pneumonia. In vitro studies, in a macrophage cell line, showed that cytotoxic strain of P aeruginosa (PA103) induced significant COX-2 protein expression and enzymatic function. In vivo data showed that infection with PA103 increased COX-2 protein production in whole lung tissue compared to mice that were infected with mutant bacteria that lack ExoU (DeltaU) or ExoU and ExoT (DeltaUT). COX-2(-/-) mice had accentuated clearance of cytotoxic P. aeruginosa from the lungs. We further tested the effects of COX-2 products such as prostaglandin E(2) on the function of phagocytic cells. Our studies indicate that prostaglandin E(2) may be involved through interacting with the EP2 receptors in modulating the host response because treatment of macrophages with prostaglandin E(2) suppressed production of reactive oxygen species. Furthermore there was enhanced bacterial clearance in EP2 receptor(-/-) mice compared to the wild-type controls. Thus it is possible that inhibition of COX-2 or EP2 receptors could be an effective adjunctive treatment for severe or resistant P. aeruginosa pneumonia.  相似文献   
65.
Leishmania donovani is an intracellular protozoan parasite that impairs the host macrophage immune response to render it suitable for its survival and establishment. L. donovani-induced immunosuppression and alteration of host cell signaling is mediated by ceramide, a pleiotropic second messenger playing an important role in regulation of several kinases, including mitogen-activated protein kinase and phosphatases. We observed that the endogenous ceramide generated during leishmanial infection led to the dephosphorylation of protein kinase B (PKB) (Akt) in infected cells. The study of ceramide-mediated Akt phosphorylation revealed that Akt was dephosphorylated at both Thr308 and Ser473 sites in infected cells. Further investigation demonstrated that ceramide was also responsible for the induction of PKCzeta, an atypical Ca-independent stress kinase, as well as the ceramide-activated protein phosphatases (e.g., protein phosphatase 2A [PP2A]). We found that Akt dephosphorylation was mediated by ceramide-induced PKCzeta-Akt association and PP2A activation. In addition, treatment of L. donovani-infected macrophages with PKCzeta-specific inhibitor peptide could restore the translocation of phosphorylated Akt to the cell membrane. This study also revealed that ceramide is involved in the inhibition of proinflammatory cytokine tumor necrosis factor alpha release by infected macrophages. These observations strongly suggest the importance of ceramide in the alteration of normal cellular functions, impairment of the kinase/phosphatase balance, and thereby establishment of leishmaniasis in the hostile macrophage environment.  相似文献   
66.
Role of DNA flow cytometry and image cytometry on effusion fluid   总被引:7,自引:0,他引:7  
The objective of the study was to assess the value of DNA flow cytometry (FCM) and image cytometry (ICM) as an adjunct to routine diagnostic cytology. In this prospective study, 100 consecutive effusion fluids were studied for routine cytology, DNA FCM, and in selected cases, ICM. One half of the centrifuged fluid sample was used for routine cytology and the remaining portion was used for DNA FCM. Nuclear area, nuclear diameter, nuclear perimeter, nuclear convex perimeter, nuclear roundess, and nuclear convex area were measured on at least 100 cells by ICM in cytologically malignant or DNA aneuploid cases along with control cases. Clinical follow-up was done in all cases. There were 22 cytologically malignant cases and 78 cytologically benign cases. Among the 22 cytologically malignant cases, there were 11 aneuploid and diploid cases each by DNA FCM. Out of 78 cytologically benign cases, six (7.7%) were aneuploid by DNA FCM. Smears of these cases showed predominantly reactive mesothelial cells, but the DNA histograms showed hypodiploid (one), hyperdiploid (three), tetraploid (one), and hypertetraploid (one) aneuploidy. Follow-up of these cases showed clinical or histologic features of malignancy except in one case of tetraploid aneuploidy, which did not show any features of malignancy and responded well to antitubercular therapy. Therefore, out of 27 malignant effusions, DNA FCM picked up 16 cases and routine cytology detected 22 cases. Sensitivity and specificity of DNA FCM were thus 59.25% and 98.63%, respectively. There was a statistically significant difference (Student's unpaired t-test, P < 0.05) between cytologically malignant cases and control benign cases in all the nuclear morphometric parameters except for nuclear roundness. There was, however, no statistically significant difference of nuclear morphometric parameters between cytologically benign vs. DNA aneuploid cases and control benign cases. DNA FCM is a useful adjunct for routine diagnostic cytology. Visual diagnostic cytology and morphometric digital microscopy miss some cases of malignancy which can be detected by DNA flow cytometry. Diagn. Cytopathol. 2000;22:81-85.  相似文献   
67.
Aims of the present paper was to study cell death by apoptosis and cell proliferation in normal cervical biopsies, cervical intraepithelial neoplasms (CIN) and squamous cell carcinomas of cervix (CaCx). There were each seven cases of normal cervical biopsy, CIN1 and CIN2 along with 10 cases of CIN3 and 14 cases of CaCx. Percentage of apoptotic cells and bodies (i.e. apoptotic index, AI) and mitoses (i.e. mitotic index, MI) and turnover index (TI - AI + MI) were counted in formalin fixed, paraffin embedded, haematoxylin and eosin stained slides. AgNOR stain was done and mean AgNOR dots per cell was also estimated. AI, MI and TI were correlated with histology grade of CIN and invasive carcinoma cervix. Mean AI, MI, TI and AgNOR count increased from lower to higher grades of CIN. AI, MI & TI raised significantly from CIN3 to carcinomas; AI, TI & AgNOR count raised significantly from CIN1 to combined CIM2 & 3; TI & AgNOR count were high in CIN1 to CIN2; AI & TI were significantly raised in normal to CIN1. In conclusion, TI is probably more important for cell kinetic analysis of CIN and carcinoma of cervix because it reflects the frequency of two important events i.e. mitosis and cell death. Sudden increase of AI, MI, TI count from CIN3 to CaCx may indicate the possibility of genetic alteration of cells of CIN3 which induces a frank malignant transformation from CIN3 to CaCx.  相似文献   
68.
BackgroundThe use of immune checkpoint inhibitors combined with vascular endothelial growth factor (VEGF)-targeted therapy as second-line treatment for metastatic clear cell renal cancer (mRCC) has not been evaluated prospectively.ObjectiveTo evaluate the efficacy and safety of atezolizumab + bevacizumab following disease progression on atezolizumab or sunitinib monotherapy in patients with mRCC.Design, setting, and participantsIMmotion150 was a multicenter, randomized, open-label, phase 2 study of patients with untreated mRCC. Patients randomized to the atezolizumab or sunitinib arm who had investigator-assessed progression as per RECIST 1.1 could be treated with second-line atezolizumab + bevacizumab.InterventionPatients received atezolizumab 1200 mg intravenously (IV) plus bevacizumab 15 mg/kg IV every 3 wk following disease progression on either atezolizumab or sunitinib monotherapy.Outcome measurements and statistical analysisThe secondary endpoints analyzed during the second-line part of IMmotion150 included objective response rate (ORR), progression-free survival (PFS), and safety. PFS was examined using Kaplan-Meier methods.Results and limitationsFifty-nine patients in the atezolizumab arm and 78 in the sunitinib arm were eligible, and 103 initiated second-line atezolizumab + bevacizumab (atezolizumab arm, n = 44; sunitinib arm, n = 59). ORR (95% confidence interval [CI]) was 27% (19–37%). The median PFS (95% CI) from the start of second line was 8.7 (5.6–13.7) mo. The median event follow-up duration was 19.4 (12.9–21.9) mo among the 25 patients without a PFS event. Eighty-six (83%) patients had treatment-related adverse events; 31 of 103 (30%) had grade 3/4 events. Limitations were the small sample size and selection for progressors.ConclusionsThe atezolizumab + bevacizumab combination had activity and was tolerable in patients with progression on atezolizumab or sunitinib. Further studies are needed to investigate sequencing strategies in mRCC.Patient summaryPatients with advanced kidney cancer whose disease had worsened during treatment with atezolizumab or sunitinib began second-line treatment with atezolizumab + bevacizumab. Tumors shrank in more than one-quarter of patients treated with this combination, and side effects were manageable.  相似文献   
69.
Image registration and fusion of whole-body (18)F-FDG PET with thoracic CT would allow combination of anatomic detail from CT with functional PET information, which could lead to improved diagnosis or PET-based radiotherapy planning. METHODS: We have designed a practical and fully automated algorithm for the elastic 3-dimensional image registration of whole-body PET and CT images, which compensates for the nonlinear deformation due to breath-hold CT imaging. A set of 18 PET and CT patient datasets has been evaluated by the algorithm. Initially, a 9-parameter linear registration is performed by maximizing the mutual information (MI)-based cost function, between the CT and the combination of emission and transmission PET volumes, using progressively increased matrix sizes to increase speed and provide better convergence. Subsequently, lung contours on transmission maps and corresponding contours on CT volumes are automatically detected. A large number (few hundreds) of corresponding point pairs are automatically derived, defining a thin-plate-spline (TPS) elastic transformation of PET emission and transmission scans to match the CT scan. RESULTS: In all 18 patients the automatic linear registration with multiresolution converged close to the final alignment, but, in 10 cases, the nonlinear differences in the diaphragm position and chest wall were still clearly visible. The nonlinear adjustment, which was in the order of 40-75 mm, significantly improved the alignment between breath-hold CT and PET, especially in the areas of the diaphragm. Lung volumes measured from transmission and CT scans match closely after the warping has been applied. The average computation time is <40 s for the linear component and <30 s for the nonlinear component for a typical PET scan with 4-6 bed positions. CONCLUSION: We have developed a technique for automatic nonlinear registration of CT and PET whole-body images to common spatial coordinates. This technique may be applied for automatic fusion of PET with CT acquired on stand-alone scanners during normal breathing or breath-hold data acquisition.  相似文献   
70.

Background

With the advent of secondary androgen receptor (AR)-targeted therapies in metastatic castration resistant prostate cancer (PC), nonadenocarcinoma PCs are becoming more prevalent. Many of these cancers express neuroendocrine markers, which may provide biomarkers for emergence of this disease state. We aimed to quantify the expression of synaptophysin (Syp) on circulating tumor cells (CTCs) from serial samples of patients being treated with abiraterone acetate or enzalutamide.

Methods

CTCs were isolated from 44 patients with castration resistant PC before starting abiraterone or enzalutamide, at 4, 8, and 12 weeks on therapy, and at progression. Patients were stratified into 3 groups: de novo resistance, short response, and long response. CTCs were enumerated on the CellSearch platform and Syp expression was quantified using the open fluorescent channel on the platform. Correlative analyses were performed.

Results

A baseline CTC count of 5 or greater was associated with a more rapid time to progression and increasing CTC counts correlated with emergence of drug resistance. Syp was readily detectable on the surface of CTCs, and baseline percentage CTC Syp expression was significantly associated with time to progression. Furthermore, in evaluable patients, percent CTC Syp expression increased with the emergence of drug resistance. We also found that prior exposure to AR-targeted therapies was inversely associated with progression free survival.

Conclusions

We have demonstrated that Syp can be quantified on CTCs and that Syp expression correlates with resistance to abiraterone and enzalutamide. Larger studies testing Syp as a biomarker of emergence of nonadenocarcinoma disease and as a marker of response to AR-targeted therapies are warranted.  相似文献   
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