Kenneth J Moise

University of Texas Health Science Center at Houston, Houston, Texas, United States

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Publications (141)533.17 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Preterm premature rupture of membranes remains a major complication after fetoscopic laser surgery (FLS) for twin-twin transfusion syndrome (TTTS). We studied the histologic changes of fetal membranes post-FLS and investigated a possible impact of amniotic fluid (AF) dilution. Fetal membranes of 31 pregnancies that underwent FLS for TTTS were investigated histologically at delivery at different sites: trocar site of recipient sac and at distance, donor sac and inter-twin membrane. The trocar insertion site on the recipient sac showed no signs of histologic hallmarks of healing. Wide-spread alteration in collagen organization and higher apoptotic index in the amnion of the recipient sac which were absent in donor's and reference membranes. To explain the mechanisms, we analyzed the AF composition of recipient sacs from TTTS pregnancies versus GA-matched healthy singleton controls and found glucose, protein and lactate dehydrogenase activity were all significantly lower in TTTS sacs consistent with over-dilution of recipient's AF (~2 fold). In-vitro exposure of healthy amniochorion to analogous dilutional stress conditions recapitulated the histologic changes and induced apoptosis and autophagy. Alteration in structural integrity of the recipient's amniochorion, possibly in response to dilution stress, along with ineffective repair mechanisms may explain the increased incidence of preterm birth post-FLS.Pediatric Research (2015); doi:10.1038/pr.2015.105.
    Pediatric Research 05/2015; DOI:10.1038/pr.2015.105 · 2.84 Impact Factor
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    ABSTRACT: Objective Twin anemia-polycythemia sequence (TAPS) can occur as a unique disease or can complicate TTTS. Middle cerebral artery (MCA) Doppler studies are not currently part of the routine evaluation of monochorionic twins since they are not used in the Quintero staging system. As such the true incidence of TAPS remains unknown at this time. We aimed to compare the characteristics and outcomes between TTTS complicated by anemia/polycythemia vs. TTTS alone.MethodsA secondary analysis of prospectively collected data of 156 consecutive cohort of patients undergoing FLS, between October 2011 and August 2014, was performed. TAPS was defined as discordance in the preoperative MCA peak systolic velocity of one twin fetus ≤ 1.0 MOM and the sibling fetus ≥ 1.5 MOM. Maternal demographics as well as pre-operative, operative and post-operative variables were analyzed. Comparative statistical analysis was performed with p < 0.05 considered as significant.ResultsTTTS with anemia/polycythemia was seen in 11 cases and TTTS alone was seen in 122 cases. There was no difference in BMI, gestational age (GA) at procedure, rate of preterm premature rupture of membranes (PPROM) and GA at delivery. The TTTS with anemia/polycythemia group of patients were more likely to be older (p = 0.03) and multiparous (p = 0.04). The number of placental anastomoses was significantly lower in the TTTS with anemia/polycythemia cases (p = 0.01). The dual live birth rate was similar for both groups (p = 0.76).ConlusionCases of TTTS with anemia/polycythemia were more likely to be found in multiparous and older women and were characterized by fewer vascular anastomoses. TTTS with anemia/polycythemia is not associated with worse perinatal outcomes after laser therapy.
    Ultrasound in Obstetrics and Gynecology 05/2015; DOI:10.1002/uog.14913 · 3.14 Impact Factor
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    ABSTRACT: The objective of this study was to elucidate the possible toxic effects on the fetal tissues after exposure to two clinically relevant concentrations of granisetron. Primary cells were isolated from human fetal organs of 16-19 weeks gestational age and treated with 3ng/mL or 30ng/mL of granisetron. Cell cycle progression was evaluated by flow cytometry. ELISA was used to detect alterations in major apoptotic proteins. Up to 10% apoptosis in cardiac tissue was observed following treatment with 30ng/mL granisetron. Neither concentration of granisetron caused alteration in cell cycle progression or alterations in apoptotic proteins in any of the other tissues. At 30ng/mL granisetron concentration had the potential to induce up to 10% apoptosis in cardiac tissue; clinical significance needs further evaluation. At granisetron 3ng/mL there was no detectable toxicity or on any fetal tissue in this study. Further research is needed to confirm these preliminary findings and determine if clinically significant. Copyright © 2015 Elsevier Inc. All rights reserved.
    Reproductive Toxicology 03/2015; 53. DOI:10.1016/j.reprotox.2015.02.011 · 2.77 Impact Factor
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    ABSTRACT: OBJECTIVE: To assess the incidence, timing, and risk factors for death of the donor fetus after fetoscopic laser surgery, we evaluated our cohort of patients who underwent the procedure for twin-twin transfusion syndrome. METHODS: This was a prospective cohort study of 166 consecutive patients with twin-twin transfusion syndrome at a single center. Fetal death was diagnosed by ultrasonography after surgery and before onset of labor. Risk factors for death of the donor twin were identified on univariate analysis and then subjected to multivariate, stepwise, logistic regression analysis. RESULTS: Donor demise occurred in 20 (13%) cases and recipient twin death occurred in four (2.6%). The median procedure to death interval was 4 days (range 1-89 days). Risk factors for donor death were fetal growth discordance greater than 30% (odds ratio [OR] 6.7, 95% confidence interval [CI] 2-23), reverse end-diastolic velocity in the donor umbilical artery (OR 25.0, 95% CI 2-290), a marginal and velamentous cord insertion (OR 4.4, 95% CI 1-19), and an increased number of anastomoses (OR 1.2, 95% CI 1.1-1.5). All four donors with both fetal growth discordance greater than 30% and reverse end-diastolic velocity in the donor umbilical artery resulted in a demise. CONCLUSION: Four risk factors significantly affecting acute and delayed donor demise after fetoscopic laser surgery were identified. The presence of both fetal growth discordance greater than 30% and reverse end-diastolic velocity in the donor umbilical artery was highly predictive of donor demise in our cohort. Knowledge of these risk factors can aid in counseling and assist patients in choosing the most appropriate intervention in the management of twin-twin transfusion syndrome. LEVEL OF EVIDENCE: III
    Obstetrics and Gynecology 01/2015; DOI:10.1097/AOG.0000000000000858 · 4.37 Impact Factor
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    ABSTRACT: Objective To compare the outcomes of dichorionic triamniotic (DCTA) triplet gestations with the outcomes of a paired cohort of monochorionic diamniotic (MCDA) twin gestations undergoing laser therapy for treatment of twin-to-twin transfusion syndrome (TTTS).Methods All DCTA triplets treated at 4 referral centers were included. A matched cohort group of MCDA twin gestations affected by TTTS was used for comparison.Results16 sets of DCTA triplets treated with laser photocoagulation of placental anastomosis were compared to 32 matched sets of MCDA twins. All of the “singleton” fetuses in the triplet gestations survived to birth and to the end of the neonatal period. There were no differences in the single or double survival or the rate of non-survivors to birth and at 28 days of life. A mean 3-week difference was found in the procedure-to-delivery interval in DCTA triplets vs. MCDA twins [60 ± 35.8 days vs. 83.6 ± 33.2 days; p = 0.029]. A mean difference of 3 weeks was also found in the gestational age at delivery in DCTA triplets vs. MCDA twins [28.5 ± 3.5 weeks vs. 31.9 ± 5weeks; p = 0.024]. A similar post-laser fetal growth pattern in donors and recipients of both groups was noted.ConclusionsDCTA triplet gestations with TTTS have a similar rate of post-laser survival but deliver earlier than can be expected for twins treated with laser. These findings have potential implications for prematurity risks and long-term outcomes.
    Ultrasound in Obstetrics and Gynecology 11/2014; 44(5). DOI:10.1002/uog.13369 · 3.14 Impact Factor
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    ABSTRACT: Objective To determine the risk faxtors for spontaneous preterm delivery (sPTD) or preterm premature rupture of membranes <34 weeks gestation after fetoscopic laser surgery for twin-twin transfusion syndrome (TTTS) and to identify the optimal threshold for pre-operative cervical length (CL).Study DesignSecondary analysis of prospectively collected data from 449 patients from 3 fetal centers was analyzed. CL measurements were obtained from pre-operative transvaginal ultrasound, between the gestational ages of 16–26 weeks. The risk factors associated with sPTD <34 weeks was determined using multivariate logistic regression. We excluded patients due to dual fetal demise and maternal or fetal indications for delivery without preterm premature rupture of membranes(n = 63). The optimal threshold for cervical length to predict sPTD <34 weeks was determined using receiver operator characteristics (ROC) curve and Youden index. Additionally, CL threshold for sPTD between 24 to 34 weeks, at every 2 weeks was determined.ResultssPTD <34 weeks occurred in 206 (53.4%) in the included patients. Only the pre-operative CL was significantly associated with sPTD. The pre-operative CL was normally distributed with a mean of 37.6 ± 10.3 mm (range 5–66 mm). Maternal age and parity were positively associated and gestational age at procedure and anterior placenta were negatively associated with cervical length on a multivariate linear regression. The area under the ROC curve for predicting sPTD with CL measurement was 0.61 (p = 0.02) and the optimal threshold was 28 mm with Youden index of 0.20 (sensitivity, and specificity of 92% and 27%, respectively). CL <25-28 mm increased risk for sPTD various all gestational age thresholds.ConclusionsPTD <34 weeks is associated with pre-operative CL < 28 mm. Preventive strategies should focus on this high-risk group.
    Ultrasound in Obstetrics and Gynecology 10/2014; 45(2). DOI:10.1002/uog.14696 · 3.14 Impact Factor
  • Kenneth J Moise
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    ABSTRACT: Until recently, all twin pregnancies were treated in a similar fashion. Ultrasounds were undertaken every 3 to 4 weeks to assess serial fetal growth. Monochorionic (MC) twins comprise only 20% of all twin pregnancies yet unique complications such as twin-twin transfusion syndrome (TTTS), twin reversed arterial perfusion sequence, twin anemia-polycythemia sequence, and selective intrauterine growth restriction can occur. In addition, the in utero death of one twin of a MC pair poses significant risks for death or severe neurologic morbidity in the cotwin. With the exception of discordant growth, these complications are not seen in dichorionic twinning due to the lack of placental anastomoses. In the last two decades, new technologies such as laser photocoagulation for the treatment of severe TTTS and radiofrequency ablation and bipolar cautery for selective reduction have markedly improved outcomes for many of the complications of MC twins. Thus, stratification of "low-risk" twinning (dichorionic twins) versus "high-risk" twinning (MC twins) is paramount to improved outcomes. This can be easily and accurately accomplished with first trimester ultrasound by evaluating the interface of the intertwin membrane with the placenta. This should now be the standard of care for all multiple gestations.
    American Journal of Perinatology 07/2014; 31. DOI:10.1055/s-0034-1382256 · 1.60 Impact Factor
  • Kenneth J Moise
    American Journal of Perinatology 07/2014; 31. DOI:10.1055/s-0034-1382775 · 1.60 Impact Factor
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    ABSTRACT: The objective of this study was to estimate maternal-fetal transplacental passage of granisetron in an ex vivo placental perfusion model. Term human placentas (N=8) were collected immediately after delivery. A single cotyledon from each placenta was perfused granisetron concentration to mimic systemic maternal peak plasma concentrations following either IV (50ng/mL) or transdermal administration (5ng/mL). To assess drug transfer and accumulation, samples were collected from maternal and fetal compartments. In the 50ng/mL open model, the mean transport fraction was 0.21 ± 0.08 with clearance index of 0.53±0.66. Fetal peak concentrations achieved was 5.6±6.6ng/mL with mean accumulation of 5.35±6.4ng/mL. No drug was detected in the fetal compartment with the 5ng/mL models. Transplacental passage of granisetron was inconsistent at the 50ng/mL concentration that achieved with IV dosing. However, there consistently was no detectable passage in all the placentas evaluated of the granisetron at 5ng/mL concentration that would be achieved after transdermal patch administration.
    Reproductive Toxicology 07/2014; 49. DOI:10.1016/j.reprotox.2014.06.003 · 2.77 Impact Factor
  • Article: Editorial.
    Kenneth J Moise, Susan R Hintz
    American Journal of Perinatology 06/2014; DOI:10.1055/s-0034-1382253 · 1.60 Impact Factor
  • Kenneth J Moise
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    ABSTRACT: The Fetal Treatment Center founded by Michael Harrison is credited as the birthplace of fetal surgery. His trainees in pediatric surgery subsequently founded fetal centers throughout the United States. In Europe, the advent of minimally invasive fetal surgical techniques led to the establishment of treatment centers led predominantly by perinatologists. More recently, perinatologists in North America have begun to play a greater role in the field of fetal intervention.Intrauterine transfusion for the treatment of hemolytic disease of the fetus/newborn was the first successful fetal intervention. Although not subjected to the rigors of clinical trials, this treatment has withstood the test of time. Interventions for other fetal disease states such as twin-twin transfusion and repair of fetal myelomeningocele were investigated in animal models followed by randomized clinical trials before widespread adoption. Tracheal occlusion for diaphragmatic hernia is still currently being investigated as the next promising step in fetal intervention.
    American Journal of Perinatology 02/2014; 31(7). DOI:10.1055/s-0033-1364191 · 1.60 Impact Factor
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    ABSTRACT: Despite improved perinatal survival following fetoscopic laser ablation (FLA) for twin twin transfusion syndrome (TTTS), prematurity remains an important contributor to perinatal mortality and morbidity. The objective of the study was to identify risk factors for complicated preterm delivery after FLA. Retrospective cohort study of prospectively collected data on maternal/fetal demographics and pre-operative, operative and post-operative variables of 459 patients treated in 3 U.S. fetal centers . Multivariate linear regression was performed to identify significant risk factors associated with preterm delivery, which was cross-validated using K-fold method. Multivariate logistic regression was performed to identify risk factors for early vs. late preterm delivery based on median gestational age at delivery of 32 weeks. There were significant differences in case selection and outcomes between the centers. After controlling for the center of surgery, a multivariate analysis indicated a lower maternal age at procedure, history of previous prematurity, shortened cervical length , use of amnioinfusion, 12 Fr cannula diameter, lack of a collagen plug placement and iatrogenic preterm premature rupture of membranes (iPPROM) were significantly associated with a lower gestational age at delivery. Specific fetal/maternal and operative variables are associated with preterm delivery after FLA for the treatment of TTTS. Further studies to modify some of these variables may decrease the perinatal morbidity after laser therapy.
    Ultrasound in Obstetrics and Gynecology 01/2014; 43(1). DOI:10.1002/uog.13206 · 3.14 Impact Factor
  • Kenneth J Moise
    Obstetrics and Gynecology 12/2013; 122(6):1306. DOI:10.1097/AOG.0000000000000036 · 4.37 Impact Factor
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    ABSTRACT: Introduction Fetal exsanguination is a rare complication of cordocentesis. Successful correction of fetal thrombocytopenia is essential for the reduction of risks. Case Report A 25-year-old, gravida 3, P2-0-0-0-2, was referred at 27 weeks of gestation for evaluation of newly diagnosed nonimmune hydrops secondary to parvovirus infection. Despite the use of ancillary platelet transfusions to correct the severe fetal thrombocytopenia, prolonged bleeding from the cord puncture site still occurred, necessitating five intrauterine transfusions to ultimately correct the fetal anemia. Conclusions The use of a smaller-diameter procedure needle, correction of the fetal thrombocytopenia early in the procedure, and external cord compression with the ultrasound transducer were ultimately successful measures in allowing for minimal loss of transfused red cells from the intravascular compartment.
    10/2013; 3(2):75-8. DOI:10.1055/s-0033-1341576
  • Kenneth J Moise
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    ABSTRACT: Amniotic fluid is typically measured by ultrasound using the amniotic fluid index (AFI) or the maximum vertical pocket (MVP). Although both parameters correlate poorly with the actual amniotic fluid volume measured with dye-dilution methods, cross-sectional studies have been used to establish gestational norms. The current acceptable definition of polyhydramnios in the late second and the third trimester in both singleton and multiple gestations is a MVP > 8cm, while the definition of oligohydramnios is a MVP < 2cm. The pocket to be measured should exclude the umbilical cord or fetal parts. Randomized clinical trials have indicated that defining oligohydramnios as a MVP < 2cm will result in fewer obstetrical interventions and similar perinatal outcomes when compared to an AFI < 5cm.
    Seminars in perinatology 10/2013; 37(5):370-4. DOI:10.1053/j.semperi.2013.06.016 · 2.42 Impact Factor
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    ABSTRACT: Objective Despite fetoscopic laser ablation (FLA) having emerged as an effective treatment for twin-twin transfusion syndrome (TTTS), major postintervention challenges, such as iatrogenic preterm premature rupture of membranes (iPPROM), remain. A chorioamniotic plug (CAP) made of absorbable gelatin sponge has been used to seal the trocar entry site in the chorioamniotic layers to promote healing and prevent iPPROM, yet the results have been equivocal. Our objective was to test the hypothesis that, following FLA for TTTS, iPPROM may be prevented by placement of an absorbable gelatin CAP. MethodsA retrospective cohort study was performed on prospectively collected data from 134 consecutive patients who underwent FLA for TTTS. The decision for CAP placement was at the discretion of the physician. Preoperative, operative and postoperative variables were collected and analyzed. The primary outcome was the incidence of iPPROM, and the secondary outcomes were procedure-to-delivery interval and gestational age at delivery. Comparative statistical analysis was performed as appropriate. ResultsA CAP was placed in 72 (54%) of 134 patients. Factors significantly associated with CAP placement were higher gravidity (P = 0.03), anterior placentation (P = 0.04), general endotracheal intubation (P = 0.02) and a cannula diameter of 12-Fr (P = 0.003). There were no differences between CAP and no-CAP groups in the rate of iPPROM (39% vs 34%, respectively; P = 0.42) or in the procedure-to-delivery interval (65.3 34.7 days vs 58.2 +/- 30.8 days, respectively; P = 0.21). The gestational age at delivery was later in the CAP group compared with the no-CAP group (30.7 +/- 4.5 weeks vs 28.9 +/- 3.9 weeks, respectively; P = 0.02). Conclusions CAP did not reduce the overall risk for iPPROM and did not increase the procedure-to-delivery interval. Further research is needed to identify other methods to prevent iPPROM and prolong pregnancy after laser therapy. Copyright (c) 2013 ISUOG. Published by John Wiley & Sons Ltd.
    Ultrasound in Obstetrics and Gynecology 09/2013; 42(4). DOI:10.1002/uog.12487 · 3.14 Impact Factor
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    ABSTRACT: OBJECTIVE: To understand the biological pathways involved in twin-twin transfusion syndrome (TTTS) by performing global gene expression analysis of amniotic fluid (AF) cell-free RNA. METHODS: Prospective whole transcriptome microarray study analyzing cell-free RNA in AF from TTTS recipient twins and singleton controls. Significantly differentially-regulated genes in TTTS cases (N = 8) vs. matched controls (N = 8) were identified and pathways analyses performed. Significant gene expression differences between Stage II TTTS recipients (N = 5) and Stage III TTTS recipients with abnormal Doppler measurements (N = 5) were also analysed. RESULTS: Analysis of paired data from TTTS cases and controls revealed differential expression of 801 genes, which were significantly enriched for neurological disease and cardiovascular system pathways. We also identified cardiovascular genes and pathways associated with the presence of critically abnormal Doppler measurements in Stage III TTTS recipients. CONCLUSIONS: This study provides the first transcriptome-wide data on the impact of TTTS on fetal development. Our results show that gene expression involving neurological and cardiovascular pathways are altered in recipient fetuses prior to surgical treatment. This has relevance for the origins of long-term complications seen in survivors and for the development of future fetal biomarkers. This article is protected by copyright. All rights reserved.
    Prenatal Diagnosis 09/2013; 33(9). DOI:10.1002/pd.4150 · 3.27 Impact Factor
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    ABSTRACT: Twin reversed arterial perfusion sequence (TRAP) is a rare complication of multiple gestations. Only a few cases of TRAP in monochorionic triplets have been reported. A case of TRAP sequence in a monochorionic, triamniotic triplet gestation treated with radiofrequency ablation (RFA) of the acardiac fetus is reported. The response to the RFA procedure and the subsequent examination of the placenta support the hypothesis of an "indirect" pump triplet. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
    Ultrasound in Obstetrics and Gynecology 07/2013; 42(1). DOI:10.1002/uog.12354 · 3.14 Impact Factor
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    ABSTRACT: INTRODUCTION: Single fetal demise in monochorionic twin gestations represents a significant risk for co-twin demise and neurodevelopmental morbidity. Indirect observations have led to a theory of acute exsanguination of the normal twin into the dying twin as the proposed mechanism. CASE: A 22-year-old G3P2 (2002) female with Quintero Stage IV twin-twin transfusion was referred for evaluation. During the course of the examination, bradycardia with impending fetal demise was noted in the recipient twin. Sudden and rapid development of tachycardia and elevation of the peak systolic velocity of the middle cerebral artery in the donor twin were witnessed. The demise of the donor twin was detected 24 hours later. Placental examination revealed one AV and two VA anastomoses. CONCLUSIONS: These observations support the "vascular sink" hypothesis for co-twin demise and neurodevelopmental abnormalities following single fetal demise in monochorionic twins. Rapid fetal exsanguination can occur even in the presence of a minimal number of placental vascular anastomoses.
    Ultrasound in Obstetrics and Gynecology 07/2013; 42(1). DOI:10.1002/uog.12480 · 3.14 Impact Factor
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    ABSTRACT: Amniotic fluid-derived stem cells (AFSC) have been reported to differentiate into cardiomyocyte-like cells and form gap junctions when directly mixed and cultured with neonatal rat ventricular myocytes (NRVM). This study investigated whether or not culture of AFSC on the opposite side of a Transwell membrane from NRVM, allowing for contact and communication without confounding factors such as cell fusion, could direct cardiac differentiation and enhance gap junction formation. Results were compared to shared media (Transwell), conditioned media and monoculture media controls. After a 2-week culture period, AFSC did not express cardiac myosin heavy chain or troponin T in any co-culture group. Protein expression of cardiac calsequestrin 2 was up-regulated in direct transmembrane co-cultures and media control cultures compared to the other experimental groups, but all groups were up-regulated compared with undifferentiated AFSC cultures. Gap junction communication, assessed with a scrape-loading dye transfer assay, was significantly increased in direct transmembrane co-cultures compared to all other conditions. Gap junction communication corresponded with increased connexin 43 gene expression and decreased phosphorylation of connexin 43. Our results suggest that direct transmembrane co-culture does not induce cardiomyocyte differentiation of AFSC, though calsequestrin expression is increased. However, direct transmembrane co-culture does enhance connexin-43-mediated gap junction communication between AFSC.
    Journal of Cellular and Molecular Medicine 05/2013; 17(6). DOI:10.1111/jcmm.12056 · 3.70 Impact Factor

Publication Stats

2k Citations
533.17 Total Impact Points


  • 2012–2015
    • University of Texas Health Science Center at Houston
      • Department of Obstetrics, Gynecology and Reproductive Sciences
      Houston, Texas, United States
    • Rice University
      • Department of Bioengineering
      Houston, TX, United States
  • 2013–2014
    • Memorial Hermann Hospital
      Houston, Texas, United States
  • 2012–2013
    • University of Texas Medical School
      • Department of Obstetrics, Gynecology & Reproductive Sciences
      Houston, Texas, United States
  • 1987–2013
    • Baylor College of Medicine
      • • Department of Pediatrics
      • • Department of Obstetrics and Gynecology
      Houston, Texas, United States
  • 2000–2012
    • University of North Carolina at Chapel Hill
      • Department of Obstetrics and Gynecology
      North Carolina, United States
  • 2010
    • Texas Children's Hospital
      Houston, Texas, United States
  • 2009
    • Society for Maternal-Fetal Medicine
      Houston, Texas, United States
  • 2006
    • University of North Carolina at Charlotte
      Charlotte, North Carolina, United States
  • 2005
    • University of Texas Medical Branch at Galveston
      Galveston, Texas, United States
  • 1998–1999
    • Houston Zoo
      Houston, Texas, United States