Harshwardhan M Thaker

Mount Sinai Medical Center, New York, New York, United States

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Publications (31)109.86 Total impact

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    Laxmi V Baxi · Mahesh Mansukhani · Harshwardhan M Thaker · Elvira Parravicini
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    ABSTRACT: Coexistence of complete mole and a live fetus is uncommon (1:22,000-100,000), more so with euploidy. We present a case of a molar pregnancy with a euploid fetus who had close fetal evaluation for second trimester bleeding. The patient presented at 29 weeks' pregnancy with decreased fetal movements, a result of fetomaternal hemorrhage. She underwent cesarean section and delivered a live infant. By close follow-up and a multidisciplinary approach, the appropriate diagnosis and a favorable outcome were achieved. Both mother and the child at 5 years of age are doing well. Detailed anatomic and molecular studies demonstrated a complete mole resulting from confined placental mosaicism, with molar tissue showing a single paternal allele at 8/8 informative loci, all shared with the fetus, thus this coexistent molar pregnancy was not that of a separate conceptus.
    Full-text · Article · Nov 2014 · The Journal of reproductive medicine
  • Rebecca N. Baergen · Harshwardhan M Thaker · Debra S Heller
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    ABSTRACT: Abstract Objectives: Placentas have been often considered medical waste in hospitals. This view is particularly held by the patients themselves who may not understand the importance of placental examination. Hospitals have been receiving requests for placental release to patients and need to be prepared to handle these requests. Therefore, a survey was conducted to explore the experiences and practices of perinatal pathologists with respect to placental release. Methods: A survey of practicing perinatal pathologists was conducted utilizing SurveyMonkey. Questions were asked about policies in force at their particular institution, conditions of release and the purpose of release, i.e. what the disposition of the placenta was after release to the family. Results: A survey was emailed to 192 perinatal pathologists in the US and Canada utilizing SurveyMonkey. 36 responses were received. 61.1% of respondents did allow release of placentas, and those who didn't release usually reported that they didn't receive requests. In most cases, specific policies were in place, with multiple departments within the hospital having input on the creation of the policy. Parental signature was required in most cases. The most common reason for patient request was to bury the placenta although some placental release was for consumption and/or encapsulation. Conclusion: Although there are no specific religious requirements for use or burial of the placenta after delivery, there are many cultural reasons for requests. Hospitals and specific providers need to be aware of this interest, and be prepared when a request is received so a specific policy can be in place.
    No preview · Article · Jul 2013 · Pediatric and Developmental Pathology
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    ABSTRACT: Array comparative hybridization has been used successfully to identify genomic alterations in stillbirth material; however, high DNA quantity and quality requirements may limit its utility in some fetal samples. Molecular inversion probe (MIP) array analysis of FFPE stillbirth autopsy samples circumvents the challenges associated with karyotype and short-term fetal cell culture, requires limited DNA input, and allows for retrospective evaluation of fetal loss. We performed MIP analysis on archival FFPE autopsy tissue to identify underlying genetic abnormalities not previously detected using traditional cytogenetic methods. Archival FFPE stillbirth cases (≥20 weeks gestation) were identified with the following characteristics: i) the phenotype suggested underlying genomic alterations; ii) the karyotype was either normal or not available and there were no other known genetic abnormalities; or iii) previous microarray testing was not performed. Genomic DNA (75 ng) was processed onto a 330,000-feature MIP array. Twenty-seven of 29 (93.1%) FFPE samples had passing MIP quality control scores. Abnormalities were seen in 3 of 27 (11%) archival samples (deletion of 17q12, trisomy 18, and a case of 4qter duplication and 13qter deletion arising from an unbalanced 4q;13q translocation), which, if identified at the time of autopsy, may have changed the course of medical management. This study highlights the benefits of using MIP array analysis for identification of genomic alterations in FFPE stillbirth autopsy tissue.
    Preview · Article · May 2013 · The Journal of molecular diagnostics: JMD
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    ABSTRACT: Context.-Molecular genotyping by analysis of DNA microsatellites, also known as short tandem repeats (STRs), is an established method for diagnosing and classifying hydatidiform mole. Distinction of both complete hydatidiform mole and partial hydatidiform mole from nonmolar specimens is relevant for clinical management owing to differences in risk for persistent gestational trophoblastic disease. Objective.-To determine the technical performance of microsatellite genotyping by using a commercially available multiplex assay, and to describe the application of additional methods to confirm other genetic abnormalities detected by the genotyping assay. Design.-Microsatellite genotyping data on 102 cases referred for molar pregnancy testing are presented. A separate panel of mini STR markers, flow cytometry, fluorescence in situ hybridization, and p57 immunohistochemistry were used to characterize cases with other incidental genetic abnormalities. Results.-Forty-eight cases were classified as hydatidiform mole (31, complete hydatidiform mole; 17, partial hydatidiform mole). Genotyping also revealed 11 cases of suspected trisomy and 1 case of androgenetic/biparental mosaicism. Trisomy for selected chromosomes (13, 16, 18, and 21) was confirmed in all cases by using a panel of mini STR markers. Conclusions.-This series illustrates the utility of microsatellite genotyping as a stand-alone method for accurate classification of hydatidiform mole. Other genetic abnormalities may be detected by genotyping; confirmation of the suspected abnormality requires additional testing.
    No preview · Article · Jan 2013 · Archives of pathology & laboratory medicine
  • Harshwardhan M Thaker · Donald D Vernon

    No preview · Article · Nov 2011 · Pediatric Critical Care Medicine
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    ABSTRACT: This study was undertaken to determine the prevalence of cervical ribs in stillborn fetuses undergoing autopsy at our institution and to search for significant associations with cervical ribs. European studies have reported an increased prevalence of cervical ribs in patients with childhood cancer and in stillborn fetuses. We reviewed data from autopsies performed at Primary Children's Medical Center, Utah, between 2006 and 2009 on 225 stillborns (≥20 weeks) and 93 deceased live-born infants (<1 year). Digital fetal radiographs in anterior-posterior and lateral views had been taken of each subject. Chi-square analysis and general linear models were used for statistical analysis of the data. The overall prevalence of cervical ribs was higher in stillborns than in live-borns who died in the first year (43.1% vs 11.8%). Karyotypes were available for 93 (41.3%) of the stillborns. Of those, cervical ribs were present in 33 of 76 (43.4%) stillborns with normal karyotype and in 13 of 17 (76.4%) stillborns with aneuploidy. Females with unavailable karyotypes were more likely to have cervical ribs than those with normal karyotypes (P  =  0.0002). This greater likelihood was not observed in males. Among the stillborns with normal karyotypes, we found no statistically significant association with gender or gestational age at fetal death. There was also no statistically significant association between congenital anomalies and the presence of cervical ribs. Our findings support the hypothesis that cervical ribs are markers for disadvantageous developmental events occurring during blastogenesis and have been subject to strong negative selection during evolution.
    No preview · Article · Jun 2011 · Pediatric and Developmental Pathology
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    ABSTRACT: Despite the recognition of the follicular variant of papillary carcinoma of the thyroid (FVPTC) for over 50 years, reproducibility of this diagnostic category has remained poor. Architectural features have been of variable utility as some FVPTC seem encapsulated, whereas others are multifocal and may be confused with nodular hyperplasia. Nuclear features are important for diagnosis of FVPTC, but some authors have discounted the utility of nuclear grooves and inclusions. More recently, BRAF and HBME-1 (Human Bone Marrow Endothelial Cell-1) have been suggested as markers for FVPTC. To investigate the frequency of BRAF mutations and HBME-1 immunopositivity, in a series of FVPTCs in which the diagnosis was established by 100% consensus among a panel of 6 surgical pathologists. Twenty-eight specimens with an original diagnosis of FVPTC and 10 cases with other diagnoses were obtained from the surgical pathology files of the University of Utah School of Medicine. All specimens were independently reviewed by 6 surgical pathologists. Tissue blocks were analyzed for BRAF exon 15 mutations and HMBE-1 expression. Complete agreement among pathologists for the diagnosis of FVPTC was obtained in 28.6% (8/28) of cases originally diagnosed as FVPTC. Mutations in BRAF exon 15 were found in 25% (2/8) of cases with a 100% consensus diagnosis of FVPTC and 32% (6/19) of cases unanimously diagnosed as a type of papillary carcinoma (classic or follicular variant). HBME-1 was expressed in 87.5% (7/8) of lesions with a 100% consensus diagnosis of FVPTC and 84.2% (16/19) of lesions with a unanimous diagnosis of a type of papillary carcinoma of the thyroid (classic or follicular variant). Interobserver agreement for the diagnosis of FVPTC is poor and testing for the BRAF mutation is only marginally helpful because a minority of FVPTCs possess the mutation. HBME-1 expression when coupled with a BRAF mutation, results in 100% specificity but low sensitivity for the presence of papillary carcinoma of the thyroid including the follicular variant.
    No preview · Article · May 2010 · Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry
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    ABSTRACT: Attempts to enhance patients' immune responses to malignancies have been largely unsuccessful. We now describe an immune-escape mechanism mediated by the inhibitory receptor Ig-like transcript 3 (ILT3) that may be responsible for such failures. Using a humanized SCID mouse model, we demonstrate that soluble and membrane ILT3 induce CD8(+) T suppressor cells and prevent rejection of allogeneic tumor transplants. Furthermore, we found that patients with melanoma, and carcinomas of the colon, rectum, and pancreas produce the soluble ILT3 protein, which induces the differentiation of CD8(+) T suppressor cells and impairs T cell responses in MLC. These responses are restored by anti-ILT3 mAb or by depletion of soluble ILT3 from the serum. Immunohistochemical staining of biopsies from the tumors and metastatic lymph nodes suggests that CD68(+) tumor-associated macrophages represent the major source of soluble ILT3. Alternative splicing, resulting in the loss of the ILT3 transmembrane domain, may contribute to the release of ILT3 in the circulation. These data suggest that ILT3 depletion or blockade is crucial to the success of immunotherapy in cancer. In contrast, the inhibitory activity of soluble ILT3 on T cell alloreactivity in vitro and in vivo suggests the potential usefulness of rILT3 for immunosuppressive treatment of allograft recipients or patients with autoimmune diseases.
    Full-text · Article · Jul 2007 · The Journal of Immunology
  • Laxmi Baxi · Stephen Brown · Harshwardhan M Thaker
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    ABSTRACT: In the literature, conflicting reports on the significance of false-positive maternal serum multiple marker testing for trisomy 18 are encountered; however, the biology of this finding is discussed infrequently. We present such a case in association with Bloom's syndrome in the fetus. The fetus had intrauterine growth restriction, seen early in the second trimester, oligohydramnios, and was delivered at 34 weeks of gestation for impending fetal compromise. We propose that the adverse outcome of the pregnancy with false-positive serum analyte testing for trisomy 18 might result from a small-sized placenta and perhaps pathology at receptor level.
    No preview · Article · Feb 2007 · Fetal Diagnosis and Therapy
  • Xiangyuan Wang · Laxmi Baxi · Debra Wolgemuth · Harshwardhan Thaker

    No preview · Article · Dec 2006 · American Journal of Obstetrics and Gynecology
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    ABSTRACT: Glycogen storage disease type IV (GSD-IV) is a rare autosomal recessive disorder due to mutations in the GBE1 gene causing deficiency of the glycogen branching enzyme (GBE). Prenatal diagnosis has occasionally been performed by the measurement of the GBE activity in cultured chorionic villi (CV) cells. Two unrelated probands with severe hypotonia at birth and death during the neonatal period were diagnosed with GSD-IV on the basis of postmortem histological findings. DNA analysis revealed truncating GBE1 mutations in both families. Prenatal diagnosis was performed in subsequent pregnancies by determination of branching enzyme activity and DNA analysis of CV or cultured amniocytes. Detailed autopsies of the affected fetuses at 14 and 24 weeks of gestation demonstrated intracellular inclusions of abnormal glycogen characteristic of GSD-IV. Prenatal diagnosis of GSD-IV by DNA analysis is highly accurate in genetically confirmed cases.
    No preview · Article · Oct 2006 · Prenatal Diagnosis
  • Young Mi Lee · Jane Cleary-Goldman · Harshwardhan M Thaker · Lynn L Simpson
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    ABSTRACT: We sought to determine the accuracy of antenatal diagnosis of twin chorionicity at a single tertiary care center and assess the consequences of incorrect diagnoses. Twins with chorionicity diagnosed by ultrasound < or = 24 weeks' gestation were retrospectively reviewed. Chorionicity was assigned by sonographic findings including placental location(s), the lambda and T-signs, and/or fetal gender(s). Postnatal diagnosis was determined by placental histopathologic examination. Medical records of antenatal-postnatal discordant chorionicities were reviewed for adverse sequelae. Chorionicity was correctly assigned antenatally in 392/410 (95.6%) twins. The sensitivity, specificity, and positive and negative predictive values of monochorionicity assessed < or = 14 weeks were 89.8%, 99.5%, 97.8%, and 97.5%. Corresponding statistical values for the second trimester were 88.0%, 94.7%, 88.0%, and 94.7%. Two cases of inaccurate antenatal diagnoses affected patient counseling or were associated with adverse clinical outcomes. Antenatal assessment of chorionicity is accurate; however, incorrect diagnoses do occur and can affect reliable patient counseling and management.
    No preview · Article · Sep 2006 · American journal of obstetrics and gynecology
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    ABSTRACT: Imprinted genes control fetal and placental growth in mice and in rare human syndromes, but the role of these genes in sporadic intrauterine growth restriction (IUGR) is less well-studied. We measured the ratio of mRNA from a maternally expressed imprinted gene, PHLDA2, to that from a paternally expressed imprinted gene, MEST, by Northern blotting in 38 IUGR-associated placentae and 75 non-IUGR placentae and found an increase in the PHLDA2/MEST mRNA ratio in IUGR (p=0.0001). Altered expression of PHLDA2 and MEST was not accompanied by changes in DNA methylation within their imprinting centers, and immunohistochemistry showed PHLDA2 protein appropriately restricted to villous and intermediate cytotrophoblast in the IUGR placentae. We next did a genome-wide survey of mRNA expression in 14 IUGR placentae with maternal vascular under-perfusion compared to 15 non-IUGR placentae using Affymetrix U133A microarrays. In this series six imprinted genes were differentially expressed by ANOVA with a Benjamini-Hochberg false discovery rate of 0.05, with increased expression of PHLDA2 and decreased expression of MEST, MEG3, GATM, GNAS and PLAGL1 in IUGR placentae. At lower significance, we found IGF2 mRNA decreased and CDKN1C mRNA increased in the IUGR cases. We confirmed the significant reduction in MEG3 non-translated RNA in IUGR placentae by Northern blotting. In addition to imprinted genes, the microarray data highlighted non-imprinted genes acting in endocrine signaling (LEP, CRH, HPGD, INHBA), tissue growth (IGF1), immune modulation (INDO, PSG-family genes), oxidative metabolism (GLRX), vascular function (AGTR1, DSCR1) and metabolite transport (SLC-family solute carriers) as differentially expressed in IUGR vs. non-IUGR placentae.
    No preview · Article · Jun 2006 · Placenta
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    W Qiu · F Schönleben · H M Thaker · M Goggins · G H Su
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    ABSTRACT: To investigate whether genetic alteration of the STK11 (serine/threonine kinase 11)/LKB1 tumor-suppressor gene is involved in the carcinogenesis of head and neck squamous cell carcinoma (HNSCC), the entire encoding exons and flanking intronic sequences of the STK11/LKB1 gene were analysed with direct genomic sequencing of 15 HNSCC specimens. A novel missense mutation with presumed loss of heterozygosity (LOH) and 10 polymorphisms were identified in these samples. The novel mutation of STK11/LKB1 at nucleotide position 613 G --> A, which causes the amino-acid substitution from alanine to threonine at residue 205 within the catalytic kinase domain, was identified in cell line RPMI 2650. To further determine whether this point mutation affects the gene function, constructs of the wild type and A205T mutant of the STK11/LKB1 gene expression vectors were created and transfected into RPMI 2650 cells. Our results showed that the reintroduction of the wild-type but not the mutant STK11/LKB1 construct into RPMI 2650 cells induced suppression of the cell growth. The mutation also affected the kinase activity of the Stk11/Lkb1 protein. This led us to conclude that the A205T point mutation of the STK11/LKB1 gene produces functionally inactive proteins. This is the first described mutation of the STK11/LKB1 gene in HNSCC. While the mutation frequency of the STK11/LKB1 gene in HNSCC remains to be determined in future studies, our data strongly suggests that STK11/LKB1 is involved in the carcinogenesis of HNSCC.
    Full-text · Article · May 2006 · Oncogene
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    ABSTRACT: Down syndrome (DS) is caused by trisomy 21 (+21), but the aberrations in gene expression resulting from this chromosomal aneuploidy are not yet completely understood. We used oligonucleotide microarrays to survey mRNA expression in early- and late-passage control and +21 fibroblasts and mid-gestation fetal hearts. We supplemented this analysis with northern blotting, western blotting, real-time RT-PCR, and immunohistochemistry. We found chromosome 21 genes consistently over-represented among the genes over-expressed in the +21 samples. However, these sets of over-expressed genes differed across the three cell/tissue types. The chromosome 21 gene MX1 was strongly over-expressed (mean 16-fold) in senescent +21 fibroblasts, a result verified by northern and western blotting. MX1 is an interferon target gene, and its mRNA was induced by interferons present in +21 fibroblast conditioned medium, suggesting an autocrine loop for its over-expression. By immunohistochemistry the p78MX1 protein was induced in lesional tissue of alopecia areata, an autoimmune disorder associated with DS. We found strong over-expression of the purine biosynthesis gene GART (mean 3-fold) in fetal hearts with +21 and verified this result by northern blotting and real-time RT-PCR. Different subsets of chromosome 21 genes are over-expressed in different cell types with +21, and for some genes this over-expression is non-linear (>1.5X). Hyperactive interferon signaling is a candidate pathway for cell senescence and autoimmune disorders in DS, and abnormal purine metabolism should be investigated for a potential role in cardiac defects.
    Full-text · Article · Mar 2006 · BMC Medical Genetics
  • J McMinn · M Wei · Y Sadovsky · H.M. Thaker · B Tycko
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    ABSTRACT: The PEG1 gene (a.k.a. MEST) is expressed in human placental trophoblast and endothelium, and data from knockout mice show that this gene regulates placental and fetal growth. Isoform 1 of PEG1 mRNA initiates from exon 1c and produces the long form of the MEST protein. This isoform is imprinted, with expression only from the paternal allele in many human and mouse organs, including placenta. In contrast, PEG1 isoform 2, initiating from exon 1a and producing the short form of MEST protein, is biallelically expressed (non-imprinted) in several non-placental organs. Here we show that PEG1 isoform 2 is in fact imprinted in a large subset of human placentae. A CpG island overlapping PEG1 exon 1a is unmethylated in various fetal and adult non-placental tissues, but is often substantially methylated in the placenta, with the extent of methylation in a large series approximating a normal distribution. Bisulfite conversion/sequencing indicates that the inter-individual differences reflect the relative representation of heavily methylated vs. unmethylated alleles, and RT-PCR/RFLP analysis shows strongly biased allelic expression of PEG1 isoform 2 mRNA in a majority of placentae with a high proportion of methylated alleles. These data highlight PEG1 isoform 2 as a marker for future studies of inter-individual epigenetic variation and its relation to placental and fetal growth in humans.
    No preview · Article · Feb 2006 · Placenta
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    ABSTRACT: We describe the clinical and pathologic features of an unusual case of alpha-thalassemia major in a patient who survived to term and lived for 9 days. The neonate was nonhydropic and the clinical picture was dominated by severe hypoxia with pulmonary hypertension. The diagnosis was not suspected until postnatal examination of the blood smear, which prompted the performance of hemoglobin electrophoresis and subsequent molecular confirmation. This case illustrates that alpha-thalassemia major should be in the differential diagnosis of hypoxic neonates even in the absence of hydrops.
    No preview · Article · Dec 2005 · Pediatric and Developmental Pathology

  • No preview · Article · Dec 2005 · American Journal of Obstetrics and Gynecology
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    ABSTRACT: To understand genetic and epigenetic pathways in Wilms' tumors, we carried out a genome scan for loss of heterozygosity (LOH) using Affymetrix 10K single nucleotide polymorphism (SNP) chips and supplemented the data with karyotype information. To score loss of imprinting (LOI) of the IGF2 gene, we assessed DNA methylation of the H19 5' differentially methylated region (DMR). Few chromosomal regions other than band 11p13 (WT1) were lost in Wilms' tumors from Denys-Drash and Wilms' tumor-aniridia syndromes, whereas sporadic Wilms' tumors showed LOH of several regions, most frequently 11p15 but also 1p, 4q, 7p, 11q, 14q, 16q, and 17p. LOI was common in the sporadic Wilms' tumors but absent in the syndromic cases. The SNP chips identified novel centers of LOH in the sporadic tumors, including a 2.4-Mb minimal region on chromosome 4q24-q25. Losses of chromosomes 1p, 14q, 16q, and 17p were more common in tumors presenting at an advanced stage; 11p15 LOH was seen at all stages, whereas LOI was associated with early-stage presentation. Wilms' tumors with LOI often completely lacked LOH in the genome-wide analysis, and in some tumors with concomitant 16q LOH and LOI, the loss of chromosome 16q was mosaic, whereas the H19 DMR methylation was complete. These findings confirm molecular differences between sporadic and syndromic Wilms' tumors, define regions of recurrent LOH, and indicate that gain of methylation at the H19 DMR is an early event in Wilms' tumorigenesis that is independent of chromosomal losses. The data further suggest a biological difference between sporadic Wilms' tumors with and without LOI.
    No preview · Article · Oct 2005 · Molecular Cancer Research
  • Harshwardhan M Thaker
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    ABSTRACT: The presence of a fetus in a molar pregnancy is usually an indication that it is a partial, rather than a complete, hydatidiform mole. The underlying reason for this is a basic difference in the genetic composition of the 2 types of mole. Complete moles are ‘‘androgenetic’’ conceptions, i.e., their genome is entirely paternal in origin [1]. The total absence of a maternal genetic contribution results in unopposed action of paternally expressed genes, leading to excessive trophoblastic proliferation and a very early cessation of embryonic development. Partial moles are almost all ‘‘diandric’’ triploids, with 1 maternal set and 2 paternal sets of chromosomes. The excess paternal genetic dose causes trophoblastic proliferation but is presumably kept in check by the maternal genetic contribution, which also permits the fetus to develop much further than in complete moles, sometimes well into the second trimester [2]. This marked difference in fetal viability between complete and partial moles has resulted in the dictum that ‘‘if it is a mole and if there is a fetus, then it must be a partial mole.’’ However, there are 2 important exceptions. First, the villi of early complete moles can show histologic evidence of fetal tissue, including endothelial cells, nucleated red cells, an amnion, and a yolk sac [3]. Second, a complete mole may be part of a dizygotic twin pregnancy in which the other conceptus is a normal well-developed fetus with its own nonmolar pla
    No preview · Article · Apr 2005 · Pediatric and Developmental Pathology

Publication Stats

828 Citations
109.86 Total Impact Points


  • 2013
    • Mount Sinai Medical Center
      New York, New York, United States
    • Icahn School of Medicine at Mount Sinai
      • Department of Pathology
      Borough of Manhattan, New York, United States
  • 2011
    • University of Utah
      Salt Lake City, Utah, United States
  • 2002-2007
    • Columbia University
      • • Department of Obstetrics and Gynecology
      • • Department of Pediatrics
      • • Institute for Cancer Genetics
      • • College of Physicians and Surgeons
      • • Comprehensive Epilepsy Center
      New York, New York, United States
  • 2004-2006
    • CUNY Graduate Center
      New York, New York, United States