Rift Valley fever virus induces fetal demise in Sprague-Dawley rats through direct placental infection.

Rift Valley fever virus (RVFV) infections in pregnant livestock cause high rates of fetal demise; miscarriage in pregnant women has also been associated with RVFV infection. To address how RVFV infection during pregnancy causes detrimental effects on the fetus, we developed a pregnant rodent model of RVFV infection. We found that pregnant rats were more susceptible to RVFV-induced death than their nonpregnant counterparts and that RVFV infection resulted in intrauterine fetal death and severe congenital abnormalities, even in pups from infected asymptomatic pregnant rats. Virus distribution in infected dams was widespread, with a previously unrecognized preference for infection, replication, and tissue damage in the placenta. In human mid-gestation placental tissue, RVFV directly infected placental chorionic villi, with replication detected in the outermost syncytial layer. Our work identifies direct placental infection by RVFV as a mechanism for vertical transmission. This is the first study to show vertical transmission of RVFV with a lethal outcome in a species other than livestock. This study highlights the potential impact of a future epidemic of this emerging mosquito-borne virus.

Diploid/triploid mixoploidy: A consequence of asymmetric zygotic segregation of parental genomes.

Triploidy is the presence of an extra haploid set of chromosomes and can exist in complete or mosaic form. The extra haploid set of chromosomes in triploid cells can be of maternal or paternal origin. Diploid/triploid mixoploidy is a unique form of triploid mosaicism that requires the aberrant segregation of entire parental genomes into distinct blastomere lineages (heterogoneic cell division) at the earliest zygotic divisions. Here we report on eight cases of diploid/triploid mixoploidy from our institution and conduct a comprehensive review of the literature. The parental origin of the extra set of chromosomes was determined in two cases; and, based on phenotypic evidence we propose the parental origin in the other cases. One case with complex mixoploidy appears to have a digynic origin in addition to the involvement of two different sperm. Of our eight cases, only one resulted in the birth of a live healthy child. The other pregnancies ended in miscarriage, elective termination of pregnancy, intrauterine fetal demise or neonatal death. A review of the literature and the results of our cases show that a preponderance of recognized cases of diploid/triploid mixoploidy has a digynic origin.

Successful Management of Giant Placental Chorangioma by Microcoil Embolization.

Optimal prenatal management of giant placental chorangioma (also known as chorioangioma, angiomyxoma, fibroangiomyxoma, or fibroma) has yet to be determined. Interventions intended to devascularize the tumor such as interstitial laser, bipolar coagulation, fetoscopic laser photocoagulation, and chemical embolization have met mixed results. We report a minimally invasive, extra-amniotic approach, technically similar to cordocentesis, of microcoil embolization of the feeding vessel. These percutaneously placed microcoils initiate clot formation at the site of insertion and are unable to migrate through the tumor, thereby minimizing fetal harm by downstream embolic phenomena. Intervention at 26 and 22 weeks resulted in intraoperative fetal loss in the former and vaginal delivery at term of a healthy neonate in the latter. Preoperative, intraoperative, and placental findings are highlighted. The ease and safety of this procedure may alter the risk-benefit equation toward earlier intervention with potentially better clinical outcomes.

Diagnostic Utility of Pax8, Pax2, and NGFR Immunohistochemical Expression in Pediatric Renal Tumors.

Pediatric renal tumors (PRT) with small round blue or spindle cell morphology can be diagnostically challenging and only a limited number of immunohistochemical markers have been documented to help in the diagnosis: paired box (Pax) 2 and nerve growth factor receptor (NGFR) positivity have been demonstrated in Wilms tumor (WT) and clear cell sarcoma of the kidney (CCSK), respectively. However, the immunohistochemical expression of these markers in other PRT remains unknown. This study investigated Pax8, Pax2, and NGFR immunophenotype in a large series of PRT. Pax8 and Pax2 showed an identical staining pattern, and were expressed in all (100%) WT while most CCSK were negative. All congenital mesoblastic nephromas, metanephric stromal tumors, primitive neuroectodermal tumors, desmoplastic small round blue cell tumors, most rhabdoid tumors, and synovial sarcomas were negative for Pax8. NGFR was expressed in 96% of CCSK (diffuse expression in 91%). Only a minority of WT stained for NGFR: 16% showed expression in the blastemal and 25% in the mesenchymal components. NGFR expression was noted in synovial sarcomas (67%, with diffuse expression seen in only 1 case, 8%), rhabdoid tumors (19%), cellular congenital mesoblastic nephromas (13%) and metanephric stromal tumors (12.5%). Primitive neuroectodermal tumors and desmoplastic small round blue cell tumors were negative for NGFR. In conclusion, Pax8/Pax2 and NGFR are sensitive markers for the diagnosis of WT and CCSK, respectively. However, their specificity is limited by variable reactivity within a subset of other renal neoplasms.

Cystic pancreatic neoplasm in pregnancy: a case report and review of the literature.

Mucinous cystic neoplasms of the pancreas are rare tumors that tend to occur in young women. They are thought to be responsive to sex hormones. We report a case of a 32-year-old pregnant woman with a 7-month history of pain and a left upper quadrant abdominal mass. She arrived at the emergency department with exacerbation of her symptoms during week 15 of gestation. Findings from ultrasonography and magnetic resonance imaging suggested a pancreatic cyst. Percutaneous aspiration of the cyst fluid yielded mucinous fluid with an elevated carcinoembryonic antigen level. The patient underwent a spleen-preserving distal open pancreatectomy. We present herein a brief review of the current literature on mucinous cystic neoplasms during pregnancy. On the basis of our experience and the existing knowledge of this condition, we advocate resection during the second trimester with splenic preservation.

Eccrine porocarcinoma: Report of a case with fine needle aspiration cytology, histopathology and immunohistochemistry.

BACKGROUND: Although relatively rare, eccrine porocarcinoma (EP) is widely recognized in the literature as the most common of the sweat gland adenocarcinoma types. EP is an adenocarcinoma of the eccrine sweat gland with a propensity to recur locally and metastasize to regional lymph nodes. This paper presents the second case of fine needle aspiration (FNA) cytology of an EP along with histopathology and immunohistochemistry. CASE: A 64-year-old Filipino woman had a history of EP of the right eyebrow and presented with a right preauricular mass. The cytopathologic features of the case included: (1) clusters and sheets of polyhedral epithelial tumor cells with abundant, cyanophilic, vacuolated cytoplasm; round to oval, hyperchromatic nuclei; and occasional prominent nucleoli; (2) multinucleated tumor cells; (3) singly dispersed and relatively large aggregates of parakeratotic squamous cells; and (4) a background of necrotic debris. CONCLUSION: EP is crucial to developing an effective (curative) surgical plan. FNA cytology potentially provides a convenient, safe and effective approach to solving a challenging differential diagnosis. The constellation of cytologic findings probably is distinctive and, in the proper clinical setting, may be diagnostic. History is important in making an accurate diagnosis.

International neuroblastoma pathology classification adds independent prognostic information beyond the prognostic contribution of age.

Age has been used as a prognostic factor for patients with peripheral neuroblastic tumours (pNTs). The latest analysis disclosed a cut-off around 18 months for the optimal prognostic distinction. The International Neuroblastoma Pathology Classification (INPC) distinguishes favourable and unfavourable histology based on the age-appropriate evaluation of histologic indicators (grade of neuroblastic differentiation, mitosis-karyorrhexis index) in the categories of neuroblastoma and ganglioneuroblastoma, nodular. This study showed that age tested by using 3 different cut-offs (12, 18, 24 months) was prognostically significant. INPC remained prognostically significant regardless of the age group to which it was applied. Prognostic effects of age and histologic indicators were independently significant, i.e., age had prognostic ability beyond that of histologic indicators, and histologic indicators had prognostic ability beyond that of age. Due to the fact that INPC incorporated age factor (18, 60 months) in the system, it served better than age by itself for prognostic distinction of pNT patients.

Genetic approaches to craniofacial tissue repair.

This review discusses in some detail the opportunities and challenges of applying gene therapy to the important clinical problem of wound repair and regeneration.