On a trip to Mozambique while in med school here at Stanford, I saw the power of market interventions to improve population health. In Pediatric Leadership for the Underserved residency at UCSF, I helped Jacaranda Health establish their pediatric clinic in Nairobi. Now, I split my time between the Stanford NICU and Virta, where I direct the digitally delivered diabetes reversal clinic.
Clinical Assistant Professor, Pediatrics - Neonatal and Developmental Medicine
Honors & Awards
Scholar, Fulbright (2005)
Residency: University of California at San Francisco School of Medicine (2015) CA
Board Certification: American Board of Pediatrics, Pediatrics (2015)
Medical Education: Stanford University School of Medicine/Medical Center (2012) CA
Anterolateral congenital diaphragmatic hernia with omphalocele: A case report and literature review
AMERICAN JOURNAL OF MEDICAL GENETICS PART A
2013; 161A (3): 585-588
The combination of congenital diaphragmatic hernia (CDH) and omphalocele is quite rare but can be seen in several syndromes. We report on a female newborn with this combination that had not been diagnosed prenatally. The patient suffered respiratory failure that persisted despite intensive care support, suggesting severe secondary pulmonary hypoplasia. Autopsy revealed the combination of an anterolateral CDH and omphalocele in the absence of other anomalies. We believe this to be the first such case to be reported in the literature.
View details for DOI 10.1002/ajmg.a.35703
View details for Web of Science ID 000315341700025
CRE recombinase-based positive-negative selection systems for genetic manipulation in Trypanosoma brucei
MOLECULAR AND BIOCHEMICAL PARASITOLOGY
2008; 157 (1): 73-82
The limited repertoire of drug-resistance markers imposes a serious obstacle to genetic manipulation of Trypanosoma brucei. Here we describe experiments with a fusion protein that allows positive selection for genome integration followed by CRE recombinase-mediated excision of the marker cassette that can be selected by ganciclovir, although the excision event is so efficient that selection is not strictly necessary. We describe two variants of the tetracycline-inducible pLEW100-based CRE-expression vector that reduced its toxicity when stably integrated into the genome, and we demonstrate that transient transfection of circular pLEW100-CRE is highly efficient at catalyzing marker excision. We used this approach to delete the last two enzymes of the pyrimidine synthesis pathway, creating a cell line that is resistant to fluoroorotic acid, which would allow the same enzymes (PYR6-5) to be used as an alternative negative selectable marker.
View details for DOI 10.1016/j.molbiopara.2007.10.003
View details for Web of Science ID 000253031500008
View details for PubMedID 18006158
Improved Glycemic Control With a Digital Health Intervention in Adults With Type 2 Diabetes: Retrospective Study.
2021; 6 (2): e28033
Traditional lifestyle interventions have shown limited success in improving diabetes-related outcomes. Digital interventions with continuously available support and personalized educational content may offer unique advantages for self-management and glycemic control.In this study, we evaluated changes in glycemic control among participants with type 2 diabetes who enrolled in a digital diabetes management program.The study employed a single-arm, retrospective design. A total of 950 participants with a hemoglobin A1c (HbA1c) baseline value of at least 7.0% enrolled in the Vida Health Diabetes Management Program. The intervention included one-to-one remote sessions with a Vida provider and structured lessons and tools related to diabetes management. HbA1c was the primary outcome measure. Of the 950 participants, 258 (27.2%) had a follow-up HbA1c completed at least 90 days from program start. Paired t tests were used to evaluate changes in HbA1c between baseline and follow-up. Additionally, a cluster-robust multiple regression analysis was employed to evaluate the relationship between high and low program usage and HbA1c change. A repeated measures analysis of variance was used to evaluate the difference in HbA1c as a function of the measurement period (ie, pre-Vida enrollment, baseline, and postenrollment follow-up).We observed a significant reduction in HbA1c of -0.81 points between baseline (mean 8.68, SD 1.7) and follow-up (mean 7.88, SD 1.46; t257=7.71; P<.001). Among participants considered high risk (baseline HbA1c≥8), there was an average reduction of -1.44 points between baseline (mean 9.73, SD 1.68) and follow-up (mean 8.29, SD 1.64; t139=9.14; P<.001). Additionally, average follow-up HbA1c (mean 7.82, SD 1.41) was significantly lower than pre-enrollment HbA1c (mean 8.12, SD 1.46; F2, 210=22.90; P<.001) There was also significant effect of program usage on HbA1c change (β=-.60; P<.001) such that high usage was associated with a greater decrease in HbA1c (mean -1.02, SD 1.60) compared to low usage (mean -.61, SD 1.72).The present study revealed clinically meaningful improvements in glycemic control among participants enrolled in a digital diabetes management intervention. Higher program usage was associated with greater improvements in HbA1c. The findings of the present study suggest that a digital health intervention may represent an accessible, scalable, and effective solution to diabetes management and improved HbA1c. The study was limited by a nonrandomized, observational design and limited postenrollment follow-up data.
View details for DOI 10.2196/28033
View details for PubMedID 34075880
HIV and Placental Infection Modulate the Appearance of Drug-Resistant Plasmodium falciparum in Pregnant Women who Receive Intermittent Preventive Treatment
CLINICAL INFECTIOUS DISEASES
2011; 52 (1): 41-48
Factors involved in the development of resistance to sulphadoxine-pyrimethamine (SP) by Plasmodium falciparum, particularly in the context of intermittent preventive treatment during pregnancy (IPTp), are not well known. We aimed to determine the impact of IPTp and human immunodeficiency virus (HIV) infection on molecular markers of SP resistance and the clinical relevance of resistant infections.SP resistance alleles were determined in peripheral (n = 125) and placental (n = 145) P. falciparum isolates obtained from pregnant women enrolled in a randomized, placebo-controlled trial of IPTp in Manhiça, Mozambique.Prevalence of quintuple mutant infections was 12% (23 of 185 isolates) in pregnant women who received placebo and 24% (20 of 85 isolates) in those who received SP (P = .031). When the last IPTp dose was administered at late pregnancy, mutant infections at delivery were more prevalent in placental samples (7 [23%] of 30, samples) than in peripheral blood samples (2 [7%] of 30 samples; P = .025), more prevalent in women who received IPTp-SP than in those who received placebo (odds ratio [OR], 8.13; 95% confidence interval [CI], 1.69-39.08), and more prevalent in HIV-positive women than in HIV-negative women (OR, 5.17; 95% CI, 1.23-21.66). No association was found between mutant infections and increased parasite density or malaria-related morbidity in mothers and children.IPTp with SP increases the prevalence of resistance markers in the placenta and in HIV-infected women at delivery, which suggests that host immunity is key for the clearance of drug-resistant infections. However, this effect of IPTp is limited to the period when blood levels of SP are likely to be significant and does not translate into more-severe infections or adverse clinical outcomes.
View details for DOI 10.1093/cid/ciq049
View details for Web of Science ID 000286214200007
View details for PubMedID 21148518
Comparison of Single-Copy and Multicopy Real-Time PCR Targets for Detection of Mycobacterium tuberculosis in Paraffin-Embedded Tissue
JOURNAL OF CLINICAL MICROBIOLOGY
2010; 48 (7): 2569-2570
Real-time PCR can rapidly identify Mycobacterium tuberculosis in paraffin-embedded tissue in the absence of microbiological culture. In a comparison of single-copy and multicopy PCR targets in 70 tissue samples, the sensitivities were 26% and 54%, respectively, with 100% specificity. Sensitivity was 75% for newer samples and was not decreased for acid-fast bacillus (AFB) stain-negative specimens.
View details for DOI 10.1128/JCM.02449-09
View details for PubMedID 20463168