Patient and Provider Factors Associated With Successfully Addressing Medical Needs Using Telehealth: A Cross-Sectional Survey.

Few data exist that highlight areas where telemedicine shines or struggles from the patient perspective. We conducted a retrospective analysis of patient experience data from 19,465 visits using a logistic regression to model the odds a virtual visit addressed a patient's medical needs. Patient age (80 years: OR 0.58; 95% CI, 0.50-0.67 vs 40-64 years), race (Black: 0.68; 95% CI, 0.60-0.76 vs White), and connection (telephone conversion: OR 0.59; 95% CI, 0.53-0.66 vs video success) were associated with a lower likelihood of addressing medical needs; results varied modestly across specialties. These data suggest that while telehealth is generally well accepted by patients, differences are seen among patient factors and specialty.

Twenty-first century house calls: a survey of ambulatory care providers to inform organisational telehealth strategy.

OBJECTIVES: While patient interest in telehealth increases, clinicians' perspectives may influence longer-term adoption. We sought to identify facilitators and barriers to continued clinician incorporation of telehealth into practice. METHODS: A cross-sectional 24-item web-based survey was emailed to 491 providers with ≥50 video visits (VVs) within an academic health system between 1 March 2020 and 31 December 2020. We quantitatively summarised the characteristics and perceptions of respondents by using descriptive and test statistics. We used systematic content analysis to qualitatively code open-ended responses, double coding at least 25%. RESULTS: 247 providers (50.3%) responded to the survey. Seventy-nine per cent were confident in their ability to deliver excellent clinical care through VV. In comparison, 48% were confident in their ability to troubleshoot technical issues. Most clinicians (87%) expressed various concerns about VV. Providers across specialties generally agreed that VV reduced infection risk (71%) and transportation barriers (71%). Three overarching themes in the qualitative data included infrastructure and training, usefulness and expectation setting for patients and providers. DISCUSSION: As healthcare systems plan for future delivery directions, they must address the tension between patients' and providers' expectations of care within the digital space. Telehealth creates new friction, one where the healthcare system must fit into the patient's life rather than the usual dynamic of the patient fitting into the healthcare system. CONCLUSION: Telehealth infrastructure and patient and clinician technological acumen continue to evolve. Clinicians in this survey offered valuable insights into the directions healthcare organisations can take to right-size this healthcare delivery modality.

Hospitalization Outcomes Among Patients With COVID-19 Undergoing Remote Monitoring.

Importance: Health care systems have implemented remote patient monitoring (RPM) programs to manage patients with COVID-19 at home, but the associations between participation and outcomes or resource utilization are unclear. Objective: To assess whether an RPM program for COVID-19 is associated with lower or higher likelihood of hospitalization and whether patients who are admitted present earlier or later for hospital care. Design, Setting, and Participants: This retrospective, observational, cohort study of RPM was performed at Froedtert & Medical College of Wisconsin Health Network, an academic health system in southeastern Wisconsin. Participants included patients with internal primary care physicians and a positive SARS-CoV-2 test in the ambulatory setting between March 30, 2020, and December 15, 2020. Data analysis was performed from February 15, 2021, to February 2, 2022. Exposures: Activation of RPM program. Main Outcomes and Measures: Hospitalizations within 2 to 14 days of a positive test. Inverse propensity score weighting was used to account for differences between groups. Sensitivity analyses were performed looking at usage of the RPM among patients who activated the program. Results: A total of 10 660 COVID-19-positive ambulatory patients were eligible, and 9378 (88.0%) had email or mobile numbers on file and were invited into the RPM program; the mean (SD) age was 46.9 (16.3) years and 5448 patients (58.1%) were women. Patients who activated monitoring (5364 patients [57.2%]) had a mean (SD) of 35.3 (33.0) check-ins and a mean (SD) of 1.27 (2.79) (median [IQR], 0 [0-1]) free-text comments. A total of 878 patients (16.4%) experienced at least 1 alert; 128 of 5364 activated patients (2.4%) and 158 of 4014 inactivated patients (3.9%) were hospitalized (χ21 = 18.65; P < .001). In weighted regression analysis, activation of RPM was associated with a lower odds of hospitalization (odds ratio, 0.68; 95% CI, 0.54-0.86; P = .001) adjusted for demographics, comorbidities, and time period. Monitored patients had a longer mean (SD) time between test and hospitalization (6.67 [3.21] days vs 5.24 [3.03] days), a shorter length of stay (4.44 [4.43] days vs 7.14 [8.63] days), and less intensive care use (15 patients [0.3%] vs 44 patients [1.1%]). Conclusions and Relevance: These findings suggest that activation of an RPM program is associated with lower hospitalization, intensive care use, and length of stay among patients with COVID-19.

Analysis of Clinician and Patient Factors and Completion of Telemedicine Appointments Using Video.

Importance: Telemedicine provides patients access to episodic and longitudinal care. Policy discussions surrounding future support for telemedicine require an understanding of factors associated with successful video visits. Objective: To assess patient and clinician factors associated with successful and with failed video visits. Design, Setting, and Participants: This was a quality improvement study of 137 846 scheduled video visits at a single academic health system in southeastern Wisconsin between March 1 and December 31, 2020, supplemented with patient experience survey data. Patient information was gathered using demographic information abstracted from the electronic health record and linked with block-level socioeconomic data from the US Census Bureau. Data on perceived clinician experience with technology was obtained using the survey. Main Outcomes and Measures: The primary outcome of interest was the successful completion of a scheduled video visit or the conversion of the video visit to a telephone-based service. Visit types and administrative data were used to categorize visits. Mixed-effects modeling with pseudo R2 values was performed to compare the relative associations of patient and clinician factors with video visit failures. Results: In total, 75 947 patients and 1155 clinicians participated in 137 846 scheduled video encounters, 17 190 patients (23%) were 65 years or older, and 61 223 (81%) patients were of White race and ethnicity. Of the scheduled video encounters, 123 473 (90%) were successful, and 14 373 (10%) were converted to telephone services. A total of 16 776 patients (22%) completed a patient experience survey. Lower clinician comfort with technology (odds ratio [OR], 0.15; 95% CI, 0.08-0.28), advanced patient age (66-80 years: OR, 0.28; 95% CI, 0.26-0.30), lower patient socioeconomic status (including low high-speed internet availability) (OR, 0.85; 95% CI, 0.77-0.92), and patient racial and ethnic minority group status (Black or African American: OR, 0.75; 95% CI, 0.69-0.81) were associated with conversion to telephone visits. Patient characteristics accounted for systematic components for success; marginal pseudo R2 values decreased from 23% (95% CI, 21.1%-26.1%) to 7.8% (95% CI, 6.3%-9.4%) with exclusion of patient factors. Conclusions and Relevance: As policy makers consider expanding telehealth coverage and hospital systems focus on investments, consideration of patient support, equity, and friction should guide decisions. In particular, this quality improvement study suggests that underserved patients may become disproportionately vulnerable by cuts in coverage for telephone-based services.

Augmenting patient safety through participation by design - An assessment of dual monitors for patients in the outpatient clinic.

BACKGROUND: Patients and physicians engaging together in the electronic health record (EHR) during clinical visits may provide opportunities to both improve patient understanding and reduce medical errors. OBJECTIVE: To assess the potential impact of a patient EHR display intervention on patient quality and safety. We hypothesized that if patients had a dedicated display with an explicit invitation to follow clinicians in the EHR that this would identify several opportunities to engage patients in their care quality and safety. MATERIAL AND METHODS: Physician-patient outpatient encounters (24 patients and 8 physicians) were videotaped. Encounters took place in a hospital-based general internal medicine outpatient clinic where physicians and patients had their respective EHR monitors. Following the visits, each patient and physician was interviewed for 30 min to understand their perception of the mirrored-screen setting. RESULTS: The following 7 themes were identified (a) curiosity, (b) opportunity to ask questions, (c) error identification, (d) control over medications, (e) awareness, (f) shared understanding & decision-making, (g) data privacy. These themes collectively comprised a conceptual model for how patient engagement in electronic health record use, through a dedicated second screen or an explicitly shared screen, relates to safety and quality opportunities. Therefore, the double EHR screen provides an explicit invitation for patients to join the process to influence safety. CONCLUSION: Desired outcomes include real-time error identification and better-shared understanding and decision-making, leading to better downstream follow-through with care plans.

Glucopyranosyl lipid adjuvant enhances immune response to Ebola virus-like particle vaccine in mice.

The identification of adjuvants that promote lasting antigen-specific immunity and augment vaccine efficacy are integral to the development of new protein-based vaccines. The Ebola virus-like particle (VLP) vaccine expressing Ebola virus glycoprotein (GP) and matrix protein (VP40) was used in this study to evaluate the ability of TLR4 agonist glucopyranosyl lipid adjuvant (GLA) formulated in a stable emulsion (SE) to enhance immunogenicity and promote durable protection against mouse-adapted Ebola virus (ma-EBOV). Antibody responses and Ebola-specific T cell responses were evaluated post vaccination. Survival analysis after lethal ma-EBOV challenge was performed 4 weeks and 22 weeks following final vaccination. GLA-SE enhanced EBOV-specific immunity and resulted in long-term protection against challenge with ma-EBOV infection in a mouse model. Specifically, GLA-SE elicited Th1-skewed antibodies and promoted the generation of EBOV GP-specific polyfunctional T cells. These results provide further support for the utility of TLR4 activating GLA-SE-adjuvanted vaccines.

Sorafenib combined with HER-2 targeted vaccination can promote effective T cell immunity in vivo.

The tumor microenvironment (TME) is established and maintained through complex interactions between tumor cells and host stromal elements. Therefore, therapies that target multiple cellular components of the tumor may be most effective. Sorafenib, a multi-kinase inhibitor, alters signaling pathways in both tumor cells and host stromal cells. Thus, we explored the potential immune-modulating effects of sorafenib in a murine HER-2-(neu) overexpressing breast tumor model alone and in combination with a HER-2 targeted granulocyte-macrophage colony-stimulating factor (GM-CSF)-secreting vaccine (3T3neuGM). In vitro, sorafenib inhibited the growth of HER-2 overexpressing NT2.5 tumor cells, inducing apoptosis. Sorafenib also interfered with ERK MAPK, p38 MAPK, and STAT3 signaling, as well as cyclin D expression, but did not affect HER-2 or AKT signaling. In vivo, single agent sorafenib disrupted the tumor-associated vasculature and induced tumor cell apoptosis, effectively inducing the regression of established NT2.5 tumors in immune competent FVB/N mice. Immune depletion studies demonstrated that both CD4+ and CD8+ T cells were required for tumor regression. Sorafenib treatment did not impact the rate of tumor clearance induced by vaccination with 3T3neuGM in tumor-bearing FVB/N mice relative to either sorafenib treatment or vaccination alone. In vivo studies further demonstrated that sorafenib enhanced the accumulation of both CD4+ and CD8+ T cells into the TME of vaccinated mice. Together, these findings suggest that GM-CSF-secreting cellular immunotherapy may be integrated with sorafenib without impairing vaccine-based immune responses.

Absence of FcγRIII results in increased proinflammatory response in FcγRIII-KO cardiac recipients.

BACKGROUND: Alloantibody can contribute significantly to rejection of heart transplants by activation of complement and interactions with a variety of effector cells, including macrophages and monocytes through activating FcγRI, FcγRIII, FcγRIV, the inhibitory FcγRIIB and complement receptors. These receptors link cellular and humoral immunity by bridging the antibody specificity to effector cells. Activating FcγRs are also involved in serum amyloid P component (SAP)-mediated clearance of apoptotic bodies. METHODS: B10.A (H-2a) hearts were transplanted into wild-type (WT) or FcγRIII-knockout (KO) C57BL/6 (H-2b) mouse recipients. Levels of alloantibodies and SAP in the circulation were determined by flow cytometry and enzyme-linked immunosorbent assay, respectively. Intragraft cytokine mRNA expression was measured by real-time polymerase chain reaction. Intragraft deposition of C4d, von Willebrand factor, SAP, and activated caspase 3 was visualized by immunochemistry. RESULTS: B10.A hearts in C57BL/6 FcγRIII-KO recipients were rejected acutely within 6 to 8 days compared with 10 to 14 days in WT. The rejection in FcγRIII-KO was accompanied by higher levels of circulating IgM/IgG alloantibodies and SAP than in WT recipients. Histology in FcγRIII-KO cardiac allograft recipients indicated perivascular margination of monocytes and neutrophils, vascular endothelial cell injury, and intense vasculocentric infiltrates with extensive apoptosis. Higher numbers of apoptotic cells, stronger C4d and SAP deposition, and extensive activated caspase 3 were found in areas of dense pockets of apoptotic blebs in FcγRIII-KO. CONCLUSIONS: We propose that absence of FcγRIII is associated with the lack of efficient SAP-mediated clearance of apoptotic cells through FcγRs. Apoptotic cells become immunogenic and induce enhanced inflammation, alloantibody production, and complement activation leading to accelerated cardiac allograft rejection.

The relationship between vitamin D deficiency and thoracic aortic dilatation.

BACKGROUND: Vitamin D deficiency can play a role in cardiovascular conditions, such as coronary artery disease, heart failure and hypertension. Vitamin D deficiency can activate the renin-angiotensin-aldosterone system, which in turn affects the cardiovascular system. Thus, a relationship between vitamin D deficiency and thoracic aortic dilatation (TAD) and aneurysm could be postulated. In this study, we compared 25-OH vitamin D levels between TAD and control groups. PATIENTS AND METHODS: This study included 87 patients with TAD who were 40 - 70 years old. The control group consisted of 93 patients who were 40 - 70 years old and did not have TAD. A transthoracic echocardiography was performed on each patient. Along with routine tests, the 25-OH vitamin D and parathormone (PTH) levels were analyzed. RESULTS: No statistically significant difference was found between the two groups regarding their basic characteristics. The average PTH level of the TAD group was higher than that of the control group (94.87 ± 44.96 and 66.39 ± 30.58 pg/ml, respectively; p < 0.001). The average 25-OH vitamin D level of the TAD group was lower than that of the control group (11.89 ± 7.54 and 15.98 ± 4.98 ng/ml, respectively; p = 0.001). The initial conventional echocardiographic parameters of both groups were comparable. Logistic regression analysis revealed that the PTH and 25-OH vitamin D levels were independent predictors of TAD. CONCLUSIONS: Vitamin D deficiency was found as an independent factor associated with TAD.

Oxidative stress and antioxidant enzyme activities in newborns with oesophageal atresia and their mothers.

OBJECTIVE: To measure the oxidant/antioxidant status of newborn babies with oesophageal atresia and their mothers, compared with healthy control subjects. METHODS: This case-control study included 40 participants: 10 newborns with oesophageal atresia and their mothers, and 10 healthy newborns and their mothers. Whole blood malondialdehyde (MDA) levels and the activities of antioxidant enzymes (catalase, carbonic anhydrase [CA], glucose-6-phosphate dehydrogenase [G-6-PD], and superoxide dismutase [SOD]) were measured. RESULTS: MDA levels and CA activity were significantly higher, and catalase, SOD and G-6-PD activities were significantly lower, in newborns with oesophageal atresia and their mothers than in healthy newborns and their mothers. Although CA activity was similar between the newborns and mothers in the patient group, it was significantly lower in newborns than in mothers in the healthy group. CONCLUSIONS: Increased lipid peroxidation might play an important role in the pathogenesis of oesophageal atresia. Impairment of the free radical/antioxidant balance may lead to increased free radical and decreased antioxidant levels in oesophageal atresia.

The pro-angiogenic properties of multi-functional bioactive glass composite scaffolds.

The angiogenic properties of micron-sized (m-BG) and nano-sized (n-BG) bioactive glass (BG) filled poly(D,L lactide) (PDLLA) composites were investigated. On the basis of cell culture work investigating the secretion of vascular endothelial growth factor (VEGF) by human fibroblasts in contact with composite films (0, 5, 10, 20 wt %), porous 3D composite scaffolds, optimised with respect to the BG filler content capable of inducing angiogenic response, were produced. The in vivo vascularisation of the scaffolds was studied in a rat animal model and quantified using stereological analyses. The prepared scaffolds had high porosities (81-93%), permeability (k = 5.4-8.6 x 10⁻9 m²) and compressive strength values (0.4-1.6 MPa) all in the range of trabecular bone. On composite films containing 20 wt % m-BG or n-BG, human fibroblasts produced 5 times higher VEGF than on pure PDLLA films. After 8 weeks of implantation, m-BG and n-BG containing scaffolds were well-infiltrated with newly formed tissue and demonstrated higher vascularisation and percentage blood vessel to tissue (11.6-15.1%) than PDLLA scaffolds (8.5%). This work thus shows potential for the regeneration of hard-soft tissue defects and increased bone formation arising from enhanced vascularisation of the construct.

Mean platelet volume in diagnosis of acute appendicitis in children.

BACKGROUND: The clinical diagnosis of acute appendicitis (AA) in children is still problematic in status. OBJECTIVES: To investigate the diagnostic value of mean platelet volume (MPV) in acute AA at childhood. METHODS: One hundred patients diagnosed as AA patients and 100 healthy individuals. Laboratory tests were studied in the hematology laboratory of the hospital. RESULTS: The MPV was found to be lower than normal in 48 cases in the AA group, and it was normal or higher than normal in 52 cases. In the control group, while MPV was found to be lower than normal in 13 cases, it was normal or higher than normal in 87 cases. The MPV was significantly lower in the AA group compared to the control group (p<0.001). CONCLUSION: Our study indicated that MPV significantly decreased in pediatric AA patients. Hence, we believe that taking the MPV decrease into consideration along with the White Blood Cell Count elevation would be beneficial in patients with suspicion of AA.

Treatment with riboflavin and ultraviolet light prevents alloimmunization to platelet transfusions and cardiac transplants.

BACKGROUND: Functional leukocytes in blood transfusions can cause alloimmunization. Previous studies have shown that exposure of platelet concentrates to riboflavin and light (Mirasol PRT treatment) causes irreparable modification of nucleic acids. This treatment does not interfere with platelet function but does inhibit a wide range of immunological functions of leukocytes present in platelet concentrates. The current study evaluated the ability of Mirasol treatment to prevent alloimmunization by platelet transfusions in rats. METHODS: Lewis rats received eight transfusions of untreated or Mirasol-treated platelets containing leukocytes from DA rats. Animals were subsequently challenged with a heart transplant under cyclosporine treatment. RESULTS: Mirasol treatment caused apoptosis of the leukocytes as measured by annexin V and CD45 staining. Complement split products were deposited on the apoptotic bodies in the platelet pack. The primary and secondary immunoglobulin (Ig) M and IgG responses in rats that received Mirasol-treated platelets were almost completely abolished compared to animals that received untreated platelets. Untreated platelet transfusions elicited strong IgG responses that were associated with rapid rejection of subsequent heart transplants. Rejected hearts contained macrophage infiltrates and C4d deposits. In contrast, no grafts were rejected by recipients transfused with Mirasol-treated platelets. Macrophage infiltrates and C4d deposits were decreased in these grafts. Recipients that were presensitized to untreated platelets were capable of producing a memory response to Mirasol-treated platelets that caused accelerated rejection of subsequent transplants. CONCLUSIONS: Transfusions of platelets that were treated with riboflavin and ultraviolet light prevented presensitization to transplants. However, Mirasol-treated platelets were immunogenic in presensitized recipients.

Assessment of QT interval duration and dispersion in athlete's heart.

An athlete's heart is characterized by morphological and functional changes occurring as a consequence of regular physical exercise. We sought to determine if these physiological changes lead to ventricular repolarization abnormalities in trained athletes. Forty-four trained athletes and 35 sex- and age-matched healthy sedentary controls were included in the study. A 12-lead surface electrocardiogram (ECG) was obtained from all participants. Maximum QT (QTmax) and minimum QT (QTmin) interval durations, QT dispersion (QTd) and corrected QT dispersion (QTcd) were calculated for each ECG record. Heart rate, systolic and diastolic blood pressure values were found to be identical in both groups. QTmax and QTmin interval durations were not statistically different between the athletic and control groups. Similarly, QTd and QTcd did not differ significantly between the two groups. No association was observed between an athlete's heart and ventricular heterogeneity compared with healthy sedentary controls, despite physiological and structural changes.

Comparison of QT dispersion between primary coronary angioplasty and thrombolytic therapy for acute myocardial infarction.

BACKGROUND: Previous studies have documented that reduction in QT dispersion after thrombolytic treatment in acute myocardial infarction depends on reperfusion status as well as infarct site. Primary percutaneous transluminal coronary angioplasty as compared with thrombolytic therapy has been shown to result in higher patency rates of the infarct vessel. OBJECTIVES: To evaluate whether primary PTCA has a more favorable effect on reducing QT dispersion in patients with acute MI as compared to thrombolytic treatment. METHODS: The study population included 42 consecutive patients (33 men, mean age 58 +/- 11 years) with acute MI (24 anterior wall, 18 inferior wall) who were treated with primary PTCA (group A, n = 21) or thrombolytic therapy (group B, n = 21) at 3.9 +/- 2 hours after symptom onset. QT intervals were measured before and 24 hours after treatment. RESULTS: On the admission electrocardiogram, patients with anterior MI had higher values of QT and QTc dispersions than patients with inferior MI (52 +/- 9 vs. 36 +/- 9 msec, P < 0.05 and 61 +/- 4 vs. 56 +/- 4 msec, P = 0.002, respectively). There was a significant reduction in QT and QTc dispersions from admission to 24 hours in all patients (from 50 +/- 9 to 37 +/- 9 msec, P < 0.001 and from 59 +/- 5 to 42 +/- 5 msec, P < 0.001, respectively), and also in group A (from 49 +/- 8 to 32 +/- 5 msec, P < 0.001 and from 58 +/- 5 to 38 +/- 3 msec, P < 0.001, respectively) and in group B patients (from 51 +/- 10 to 42 +/- 10 msec, P < 0.01 and from 60 +/- 4 to 46 +/- 5 msec, P < 0.001, respectively). QT and QTc dispersions were found to be shorter in group A at 24 hours after treatment than in group B (32 +/- 5 vs. 42 +/- 10 msec, P < 0.001 and 38 +/- 3 vs. 46 +/- 5 msec, P < 0.001, respectively). CONCLUSIONS: Reperfusion therapy with primary PTCA or thrombolytic agents reduces QT and QTc dispersions in acute MI. QT and QTc dispersions after reperfusion treatment are shorter with primary PTCA than with thrombolytic therapy.

RAG1/2-mediated resolution of transposition intermediates: two pathways and possible consequences.

During B and T cell development, the RAG1/RAG2 protein complex cleaves DNA at conserved recombination signal sequences (RSS) to initiate V(D)J recombination. RAG1/2 has also been shown to catalyze transpositional strand transfer of RSS-containing substrates into target DNA to form branched DNA intermediates. We show that RAG1/2 can resolve these intermediates by two pathways. RAG1/2 catalyzes hairpin formation on target DNA adjacent to transposed RSS ends in a manner consistent with a model leading to chromosome translocations. Alternatively, disintegration removes transposed donor DNA from the intermediate. At high magnesium concentrations, such as are present in mammalian cells, disintegration is the favored pathway of resolution. This may explain in part why RAG1/2-mediated transposition does not occur at high frequency in cells.

DNA transposition by the RAG1 and RAG2 proteins: a possible source of oncogenic translocations.

The RAG1 and RAG2 proteins are known to initiate V(D)J recombination by making a double-strand break between the recombination signal sequence (RSS) and the neighboring coding DNA. We show that these proteins can also drive the coupled insertion of cleaved recombination signals into new DNA sites in a transpositional reaction. This RAG-mediated DNA transfer provides strong evidence for the evolution of the V(D)J recombination system from an ancient mobile DNA element and suggests that repeated transposition may have promoted the expansion of the antigen receptor loci. The inappropriate diversion of V(D)J rearrangement to a transpositional pathway may also help to explain certain types of DNA translocation associated with lymphatic tumors.

Reiterative dG addition by Euplotes crassus telomerase during extension of non-telomeric DNA.

Telomerase from the ciliate Euplotes crassus incorporates G4T4telomeric repeats onto both telomeric and non-telomeric single-stranded DNA 3'-ends via reverse transcription of a templating domain in its RNA subunit. Here we describe an unusual mode of template copying that is characteristic of DNA synthesis onto non-telomeric 3'-ends in vitro . When dTTP was eliminated from telomerase reactions, telomeric primers or DNA products generated from the telomerase endonuclease were extended by precise copying of the RNA template. In contrast, telomerase catalyzed the addition of up to 13 dG residues onto primers with non-telomeric 3'-ends under the same reaction conditions. Introducing mismatches in the 3'-terminus of telomeric primers that reduced primer complementarity to the RNA template induced reiterative dG incorporation, indicating that the reaction is influenced by Watson-Crick base pair formation between the primer and the RNA template. Unexpectedly, the reiterative dG addition mode was confined to telomerase derived from developing cells that undergo new telomere formation. This reaction was not observed in vegetatively growing cells. We postulate that indiscriminate dG addition by telomerase occurs by reiterative copying of C residues in the telomerase RNA templating domain and reflects lateral instability of the primer-template interaction during de novo telomere formation.