Taxonomic revision of the native Magnolia (Magnoliaceae) species of Brazil.

The genus Magnolia (Magnoliaceae) has a wide and disjunct geographic distribution ranging from Eastern and South Asia to Malaysia, extending across the Neartics and reaching into the Neotropics. Regarding its infrageneric classification, the genus is divided into three subgenera: Yulania, Gynopodium and Magnolia, the latter including the section Talauma in which the native Brazilian taxa are classified. The species of Magnoliasect.Talauma can be recognized by two parallel longitudinal scars on the petiole formed by the shedding of the stipules, in addition to a woody syncarp that breaks into irregular plates at dehiscence. Currently, in Brazil, species recognition is not clear on national platforms that are widely used by the Brazilian botanical community (e.g. Flora do Brasil), with only two native Magnolia species being accepted: M.amazonica and M.ovata. The lack of knowledge about the species and their respective characteristics has resulted in many identification errors in Brazilian herbaria, which contributes to the lack of knowledge about their current conservation status. We conducted a complete taxonomic revision based on extensive fieldwork, a herbarium survey, along with literature study. Based on this, we propose to recognize three previously described species, supporting the acceptance of five native Magnolias occurring in Brazil, namely: M.amazonica, M.brasiliensis, M.irwiniana, M.ovata and M.sellowiana. However, we follow the Flora do Brasil in maintaining M.paranaensis as a synonym of M.ovata. Additionally, we designate a lectotype for M.sellowiana. We present morphological descriptions and the geographic distribution for each species, in addition to an identification key to all of these plus the two introduced ornamental species from Asia and North America, illustrations, photographs, ecological data, updated conservation status and taxonomic notes.

A Taxonomically-verified and Vouchered Checklist of the Vascular Plants of the Republic of Guinea.

The Checklist of the Vascular Plants of the Republic of Guinea (CVPRG) is a specimen-based, expert-validated knowledge product, which provides a concise synthesis and overview of current knowledge on 3901 vascular plant species documented from Guinea (Conakry), West Africa, including their accepted names and synonyms, as well as their distribution and status within Guinea (indigenous or introduced, endemic or not). The CVPRG is generated automatically from the Guinea Collections Database and the Guinea Names Backbone Database, both developed and maintained at the Royal Botanic Gardens, Kew, in collaboration with the staff of the National Herbarium of Guinea. A total of 3505 indigenous vascular plant species are reported of which 3328 are flowering plants (angiosperms); this represents a 26% increase in known indigenous angiosperms since the last floristic overview. Intended as a reference for scientists documenting the diversity and distribution of the Guinea flora, the CVPRG will also inform those seeking to safeguard the rich plant diversity of Guinea and the societal, ecological and economic benefits accruing from these biological resources.

Nursing Interventions That Promote Sleep in Preterm Newborns in the Neonatal Intensive Care Units: An Integrative Review.

Sleep is a crucial factor for the psychological and physiological well-being of any human being. In Neonatal Intensive Care Units, preterm newborns' sleep may be at risk due to medical and nursing care, environmental stimuli and manipulation. This review aims to identify the nurses' interventions that promote sleep in preterm newborns in the Neonatal Intensive Care Units. An integrative review was conducted following Whittemore and Knafl's methodology and the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. The research was carried out on the electronic databases PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and ScienceDirect, with a timeframe from 2010 to 2021. A total of 359 articles were initially identified. After selection and analysis, five studies were included in the sample. Interventions by nursing staff that promote sleep in preterm newborns in the Neonatal Intensive Care Units fall within three categories: environmental management, relaxation techniques and therapeutic positioning. Nurses play a vital role in implementing interventions that promote preterm newborns' sleep. They can positively affect preterm newborns' sleep by controlling environmental stimuli and applying relaxation techniques and therapeutic positioning to their care practices.

A Bird's Eye View of the Systematics of Convolvulaceae: Novel Insights From Nuclear Genomic Data.

Convolvulaceae is a family of c. 2,000 species, distributed across 60 currently recognized genera. It includes species of high economic importance, such as the crop sweet potato (Ipomoea batatas L.), the ornamental morning glories (Ipomoea L.), bindweeds (Convolvulus L.), and dodders, the parasitic vines (Cuscuta L.). Earlier phylogenetic studies, based predominantly on chloroplast markers or a single nuclear region, have provided a framework for systematic studies of the family, but uncertainty remains at the level of the relationships among subfamilies, tribes, and genera, hindering evolutionary inferences and taxonomic advances. One of the enduring enigmas has been the relationship of Cuscuta to the rest of Convolvulaceae. Other examples of unresolved issues include the monophyly and relationships within Merremieae, the "bifid-style" clade (Dicranostyloideae), as well as the relative positions of Erycibe Roxb. and Cardiochlamyeae. In this study, we explore a large dataset of nuclear genes generated using Angiosperms353 kit, as a contribution to resolving some of these remaining phylogenetic uncertainties within Convolvulaceae. For the first time, a strongly supported backbone of the family is provided. Cuscuta is confirmed to belong within family Convolvulaceae. "Merremieae," in their former tribal circumscription, are recovered as non-monophyletic, with the unexpected placement of Distimake Raf. as sister to the clade that contains Ipomoeeae and Decalobanthus Ooststr., and Convolvuleae nested within the remaining "Merremieae." The monophyly of Dicranostyloideae, including Jacquemontia Choisy, is strongly supported, albeit novel relationships between genera are hypothesized, challenging the current tribal delimitation. The exact placements of Erycibe and Cuscuta remain uncertain, requiring further investigation. Our study explores the benefits and limitations of increasing sequence data in resolving higher-level relationships within Convolvulaceae, and highlights the need for expanded taxonomic sampling, to facilitate a much-needed revised classification of the family.

Molecular Changes In Cardiac Tissue As A New Marker To Predict Cardiac Dysfunction Induced By Radiotherapy.

The contribution of radiotherapy, per se, to late cardiotoxicity remains controversial. To clarify its impact on the development of early cardiac dysfunction, we developed an experimental model in which the hearts of rats were exposed, in a fractionated plan, to clinically relevant doses of ionizing radiation for oncological patients that undergo thoracic radiotherapy. Rat hearts were exposed to daily doses of 0.04, 0.3, and 1.2 Gy for 23 days, achieving cumulative doses of 0.92, 6.9, and 27.6 Gy, respectively. We demonstrate that myocardial deformation, assessed by global longitudinal strain, was impaired (a relative percentage reduction of >15% from baseline) in a dose-dependent manner at 18 months. Moreover, by scanning electron microscopy, the microvascular density in the cardiac apex was significantly decreased exclusively at 27.6 Gy dosage. Before GLS impairment detection, several tools (qRT-PCR, mass spectrometry, and western blot) were used to assess molecular changes in the cardiac tissue. The number/expression of several genes, proteins, and KEGG pathways, related to inflammation, fibrosis, and cardiac muscle contraction, were differently expressed in the cardiac tissue according to the cumulative dose. Subclinical cardiac dysfunction occurs in a dose-dependent manner as detected by molecular changes in cardiac tissue, a predictor of the severity of global longitudinal strain impairment. Moreover, there was no dose threshold below which no myocardial deformation impairment was detected. Our findings i) contribute to developing new markers and exploring non-invasive magnetic resonance imaging to assess cardiac tissue changes as an early predictor of cardiac dysfunction; ii) should raise red flags, since there is no dose threshold below which no myocardial deformation impairment was detected and should be considered in radiation-based imaging and -guided therapeutic cardiac procedures; and iii) highlights the need for personalized clinical approaches.

The long road of functional recruitment-The evolution of a gene duplicate to pyrrolizidine alkaloid biosynthesis in the morning glories (Convolvulaceae).

In plants, homospermidine synthase (HSS) is a pathway-specific enzyme initiating the biosynthesis of pyrrolizidine alkaloids (PAs), which function as a chemical defense against herbivores. In PA-producing Convolvulaceae ("morning glories"), HSS originated from deoxyhypusine synthase at least >50 to 75 million years ago via a gene duplication event and subsequent functional diversification. To study the recruitment of this ancient gene duplicate to PA biosynthesis, the presence of putative hss gene copies in 11 Convolvulaceae species was analyzed. Additionally, various plant parts from seven of these species were screened for the presence of PAs. Although all of these species possess a putative hss copy, PAs could only be detected in roots of Ipomoea neei (Spreng.) O'Donell and Distimake quinquefolius (L.) A.R.Simões & Staples in this study. A precursor of PAs was detected in roots of Ipomoea alba L. Thus, despite sharing high sequence identities, the presence of an hss gene copy does not correlate with PA accumulation in particular species of Convolvulaceae. In vitro activity assays of the encoded enzymes revealed a broad spectrum of enzyme activity, further emphasizing a functional diversity of the hss gene copies. A recently identified HSS specific amino acid motif seems to be important for the loss of the ancestral protein function-the activation of the eukaryotic initiation factor 5A (eIF5A). Thus, the motif might be indicative for a change of function but allows not to predict the new function. This emphasizes the challenges in annotating functions for duplicates, even for duplicates from closely related species.

Notes on the systematics of Cuscutasect.Subulatae (subg. Grammica) with the description of Cuscutamantiqueirana, a new species from Brazil.

Cuscutamantiqueirana Costea, S.S. Silva & Sim.-Bianch. a new species from montane cloud forests of the Serra da Mantiqueira, Brazil, is described and illustrated. The morphological and phylogenetic analyses revealed that the new species belongs to sect. Subulataeofsubg.Grammica. The new species is related to C.odoratavar.botryoides, C.rotundiflora and C.globiflora from which it differs in narrower calyx lobes and the presence of four stomatiferous lobes or projections at the distal part of the ovary. A detailed morphological comparison with C.odoratavar.botryoides, morphologically the most similar taxon, is provided along with the geographical distribution, ecology and host range of the species. The morphological and phylogenetic relationships of the new species, as well as the diversity of stomatiferous projections, are discussed in the broader context of sect. Subulatae and subg. Grammica. Cuscutabolivianavar.paranensis is considered a synonym of C.odoratavar.botryoides.

The Road so Far in Colorectal Cancer Pharmacogenomics: Are We Closer to Individualised Treatment?

In recent decades, survival rates in colorectal cancer have improved greatly due to pharmacological treatment. However, many patients end up developing adverse drug reactions that can be severe or even life threatening, and that affect their quality of life. These remain a limitation, as they may force dose reduction or treatment discontinuation, diminishing treatment efficacy. From candidate gene approaches to genome-wide analysis, pharmacogenomic knowledge has advanced greatly, yet there is still huge and unexploited potential in the use of novel technologies such as next-generation sequencing strategies. This review summarises the road of colorectal cancer pharmacogenomics so far, presents considerations and directions to be taken for further works and discusses the path towards implementation into clinical practice.

Efficacy and toxicity of adjuvant chemotherapy on colorectal cancer patients: how much influence from the genetics?

We studied the predictive value for response and toxicity of functional polymorphisms in genes involved in the oxaliplatin/fluorouracil pathway in colorectal cancer patients. One hundred and twenty-seven (127) patients were treated with curative intended surgery followed by adjuvant chemotherapy with FOLFOX (fluorouracil, leucovorin and oxaliplatin) regimen. The median age was 65.53 (27-80) years (66.9% male, 59.1% rectum). The median follow-up was 8.5 years (IQR, 4.1-9.4). At the end of follow-up, 59 patients (46.5%) had relapsed or died in the whole study population. We did find that XRCC1GG genotype is associated with a higher risk of developing haematologic toxicity. Furthermore, we report a significant association of the TS 3'UTR 6 bp/6 bp polymorphism and the XRCC1 rs25487 with a higher risk of developing anaemia and diarrhoea, respectively. On the other hand, none of the studied polymorphisms showed clinically relevant association with disease-free survival and overall survival or early failure to adjuvant FOLFOX therapy.

Tumor Profiling at the Service of Cancer Therapy.

Cancer treatment options have evolved significantly in the past few years. From the initial surgical procedures, to the latest next-generation technologies, we are now in the position to analyze and understand tumors in a one-by-one basis and use that to our advantage to provide with individualized treatment options that may increase patient survival. In this review, we will focus on how tumor profiling has evolved over the past decades to deliver more efficient and personalized treatment options, and how novel technologies can help us envisage the future of precision oncology toward a better management and, ultimately, increased survival.

A informação na consulta presencial em Medicina Geral e Familiar: classificações segundo a ICPC-2 e anotações livres para a memória futura no SOAP / Information available in general practice/family medicine consultations: coding and annotations for future use / La información en la consulta médica presencial en Medicina General y Familiar: clasificaciones según ICPC-2 y apuntes libres para la memoria futura en el SOAP

Objetivos: assumindo a obrigatoriedade de classificação ICPC-2 em cada consulta, conhecer a informação, em consultas passadas pelo método de Weed-SOAP segundo o gênero e idade de quem consulta o médico (consulente ou paciente), caracterizando o nível de registro pelo método SOAP em Subjetivo (S) - classificação e anotações - em Objetivo (O) anotações sobre o estado do paciente, em Avaliação (A) da classificação e em Plano (P) da classificação e anotações. Métodos: estudo observacional, transversal em outubro de 2012, em amostra aleatorizada das consultas presenciais de dois médicos orientadores de internato de especialidade, em três meses sorteados do 1º semestre de 2012, e em quatro dias sorteados em cada mês, em amostra representativa com intervalo de confiança de 95% e margem de erro de 6%. Utilizou-se estatística descritiva e inferencial. Resultados: amostra de 318 consultas, n=149 (46,9%) no gênero masculino, n=61 (19,2%) no grupo etário <18 anos e n=194 (61,0%) no ≥18 e <65 anos, ns por grupos etários e gênero. Em S, há classificação em 98,7% e anotação em 47,2% das consultas; Em O, verificamos "As anotações demonstram o estado do paciente" em 66,0% e "As anotações são explícitas e entendíveis" em 79,9%; em A, 97,8% das consultas têm classificação; Em P, há classificação em 96,5% e anotações explicando o plano em 23,0% das consultas. Distribuição sem significado por grupo etário para as variáveis estudadas. É mais frequente haver no gênero feminino em S "As anotações são explícitas e entendíveis" e em P "Há classificação de procedimentos". Conclusão: há campo para mais completa coleta da informação na consulta, permitindo, assim, melhor conhecimento de cada consulta e caso para o futuro.

Objectives: assuming the mandatoriness of ICPC2 classification in every consultation, the objective of this study was to ascertain the frequency of this type of classification in past consultations. This analysis was performed using the Weed-SOAP method, where Subjective (S) is measured by classifications and annotations, Objective (O) by annotations, Avaliation (A) by classification, and Plan (P) by classification and annotations. Methods: a cross-sectional observational study was performed in October 2012, with a 95% confidence interval and 6% error margin, on a representative random sample of consultations conducted on 4 random days of 3 random months of the first semester of 2012, and data were analyzed using descriptive and inferential statistics. Results: among the sample of 318 consultations, 149 (46.9%) were with male patients and 61 (19.2%) were aged under 18 years, while 194 (61.0%) were aged 18 or above but under 65 years, after sorting by age groups and gender. In terms of S, 98.7% of consultations had an ICPC-2 classification and 47.2% had an annotation; in terms of O, 66.0% had an annotation demonstrating the state of the patient and 79.9% were explicit; in terms of A, 97.8% had a classification; and in terms of P, 96.5% had a classification and 23.0% had an annotation explaining the plan. There was no statistically significant difference by age group for the studied variables. However, for gender, women had more "Clear and explicit" annotations in S, and "Classification of plan" instances in P. Conclusion: more complete recall of information in consultations is required in order to gain better knowledge about individual consultations and patients for future use.

Objetivos: asumiendo la obligatoriedad de clasificar con la ICPC-2 en cada consulta, conocer la información, en consultas tras-efectuadas pelo método Weed-SOAP según el género y edad de quien consulta al médico (los pacientes), caracterizando el nivel de registro por el método SOAP en Subjetivo (S) - clasificación y anotaciones - en Objetivo (O) apuntes sobre el estado del paciente, en Evaluación (A) de la clasificación y en Pleno (P) de la clasificación y apuntes. Métodos: estudio observacional, transversal en octubre del 2012, en muestra aleatoria de las consultas presenciales de dos médicos tutores de residencia de la especialidad, por tres meses sorteados del 1º semestre del 2012 y en cuatro días sorteados en cada mes, en muestra representativa con intervalo de seguridad del 95% y margen de error del 6%. Se utilizó estadística descriptiva e inferencial. Resultados: muestra de 318 consultas, n=149 (46,9%) en el género masculino, n=61 (19,2%) en el grupo de edad <18 años y n=194 (61,0%) en el ≥18 y <65 años, ns por grupos de edad y género. En S, hay clasificación en el 98,7% y apuntes en el 47,2% de las consultas; En O, verificamos "Los apuntes demuestran el estado del paciente" en 66,0% y "Los apuntes son explícitos y comprensibles" en el 79,9%; en A, el 97,8% de las consultas tienen clasificación; En P, hay clasificación en el 96,5% y apuntes explicando el plan en el 23,0% de las consultas. Distribución sin significado por grupo de edad para las variables estudiadas. Es más frecuente haber en el género femenino en S "Los apuntes son explícitos y comprensibles" y en P "Hay clasificación de procedimientos". Conclusión: hay campo para un recogido de informaciones más completo, permitiendo de esta manera, mejor conocimiento de cada consulta en el futuro.

Hypertensive patients in a general practice setting: comparative analysis between controlled and uncontrolled hypertension.

OBJECTIVE: To study the differences between controlled and uncontrolled hypertensive patients. METHODS: This was a cross-sectional observational study of the hypertensive population on the lists of three general practitioners in the district of Coimbra in central Portugal in 2013, with a margin of error of 6% and 95% confidence interval in each sample, organized in ascending order of health care user numbers. Data were gathered electronically by the investigators after approval by the Regional Health Authority's ethics committee. RESULTS: A sample of 201 individuals was studied, of whom 104 (51.7%) were male and 86 (42.8%) were aged under 65 (p=0.127 for gender and age-group). Hypertension was controlled in 130 (64.7%). We found significant differences in target organ damage, more frequent in those with controlled hypertension (33.1% vs. 19.7%, p=0.031), in hypertension control, better in those taking at least one anti-hypertensive drug at night (56.9% vs. 29.6%, p<0.001), and in prescription of non-steroidal anti-inflammatory drugs, more frequent in those with uncontrolled hypertension (11.3% vs. 3.8%, p=0.043). CONCLUSION: Hypertension control is significantly associated with target organ damage, taking at least one anti-hypertensive drug at night and not taking non-steroidal anti-inflammatory drugs simultaneously.

Prevalence of canine heartworm (Dirofilaria immitis) disease in dogs of central Portugal.

The aim of the present study was to determine the prevalence and risk factors concerning Dirofilaria immitis infection in dogs from Figueira da Foz, located in the central region of Portugal. In the period between November 2009 and January 2011, 304 blood samples were obtained from dogs over 1 year of age, with no previous history of heartworm prevention or diagnosis. Every blood sample was analyzed using varied laboratory techniques (direct microscopic evaluation of a fresh blood sample, the modified Knott technique, and the ELISA antigen detection test - IDEXX Snapp®). In the samples in which microfilaremia was detected, a histochemical technique using acid phosphatase staining was applied to identify the species of microfilariae. A total prevalence of 27.3% (83 out of 304) was found. We also found that 73.5% of all positive cases (61 out of 83) were microfilaremic, and 26.5% were occult infections (22 out of 83). By means of a histochemical technique Dirofilaria immitis was identified in 96.7% of microfilaremic samples. A multivariate model allowed us to identify the following risk factors for the presence of heartworm disease: age between 4 and 9 years, dogs living in a rural environment, large breed dogs, and living outdoors. This study shows for the first time the high prevalence of heartworm disease in a central area of Portugal and emphasizes the importance of systematic screening for this disease, as well as the need to prevent it in dogs in this area.

Noninvasive measurement of murine hepatic acetyl-CoA ¹³C-enrichment following overnight feeding with ¹³C-enriched fructose and glucose.

The (13)C-isotopomer enrichment of hepatic cytosolic acetyl-CoA of overnight-fed mice whose drinking water was supplemented with [U-(13)C]fructose, and [1-(13)C]glucose and p-amino benzoic acid (PABA) was quantified by (13)C NMR analysis of urinary N-acetyl-PABA. Four mice were given normal chow plus drinking water supplemented with 5% [1-(13)C]glucose, 2.5% [U-(13)C]fructose, and 2.5% fructose (Solution 1) overnight. Four were given chow and water containing 17.5% [1-(13)C]glucose, 8.75% [U-(13)C]fructose and 8.75% fructose (Solution 2). PABA (0.25%) was present in both studies. Urinary N-acetyl-PABA was analyzed by (13)C NMR. In addition to [2-(13)C]- and [1,2-(13)C]acetyl isotopomers from catabolism of [U-(13)C]fructose and [1-(13)C]glucose to acetyl-CoA, [1-(13)C]acetyl was also found indicating pyruvate recycling activity. This precluded precise estimates of [1-(13)C]glucose contribution to acetyl-CoA while that of [U-(13)C]fructose was unaffected. The fructose contribution to acetyl-CoA from Solutions 1 and 2 was 4.0 ± 0.4% and 10.6 ± 0.6%, respectively, indicating that it contributed to a minor fraction of lipogenic acetyl-CoA under these conditions.

Peripheral blood pressure by Dinamap and central blood pressure by applanation tonometry in outpatient general practice.

INTRODUCTION: Central blood pressure (CBP) is the pressure exerted by the blood column at any given moment on the aortic and carotid artery walls, which is a close proxy for the blood pressure inside the brain and the heart, and is thus a better marker of cardiovascular morbidity and mortality than peripheral blood pressure (PBP). OBJECTIVE: To assess how the augmentation index (AI), peripheral pulse pressure (pPP), central pulse pressure (cPP) and subendocardial viability ratio (SEVR) vary in hypertensive patients according to level of control of CBP and PBP. METHODS: We performed an observational, cross-sectional study in a convenience sample from a general practice in Central Portugal over a period of four days in May 2010. Measurements were taken after a four-minute resting period. The following values were considered to reflect controlled pressures: PBP <140/90 mmHg, CBP <130/80 mmHg, pPP <55 mmHg and cPP <45 mmHg. RESULTS: The sample included 92 patients, 38 male (41.3%), mean age 62.3±11.1 years, with no significant difference in gender distribution. PBP was controlled in 55 (59.8%), and CBP in 53 (57.6%). Both PBP and CBP were controlled in 50 patients (54.3%) and neither was controlled in 34 (37.9%). pPP and cPP were significantly lower in those with controlled PBP (p<0.001) and CBP (p<0.001). AI was non-significantly lower in those with controlled PBP (78±9 vs. 80.7) and those with controlled CBP (78±9 vs.81±7) (p=0.02). SEVR was within the desirable range in 92 patients (92.2%). 78.4% of individuals were taking drugs acting on the renin angiotensin aldosterone system (RAAS). CONCLUSIONS: In a convenience sample of 92 patients, PBP and CBP were controlled in 59.8% and 57.6%, respectively. Those with controlled PBP had significantly better peripheral systolic and diastolic blood pressure, CBP, pPP and cPP; the same was true of those with controlled CBP, who also had a significantly better AI. The percentage of the cardiac cycle in diastole had a desirable value for 92,2% of the subjects.

Effects of transaldolase exchange on estimates of gluconeogenesis in type 2 diabetes.

Transaldolase (TA) exchange overestimates gluconeogenesis measured with deuterated water (²H2O). However, it is unknown whether TA differs in people with type 2 diabetes (T2DM). ²H2O was ingested, and [1-¹³C]acetate and [3-³H]glucose were infused in T2DM (n = 10) and healthy nondiabetic (ND; n = 8) subjects. TA was assessed from the ratio of ¹³C3 to ¹³C4 glucose enrichment (¹³C3/¹³C4) measured by ¹³C NMR. Glucose turnover was measured before (~16-h fast) and during hyperglycemic (~10 mM) moderate-dose insulin (~0.35 mU·kg⁻¹·min⁻¹) clamp. ¹³C3/¹³C4 in T2DM vs. ND was <1.0 and not different at baseline and clamp, indicating equivalent TA. To determine whether incomplete triose phosphate isomerase (TPI) exchange contributed to asymmetric ¹³C3/¹³C4, [U-¹³C]glycerol was infused in lieu of [1-¹³C]acetate during a separate visit in a subset of ND (n = 7) subjects. Ratio of ¹³C3/¹³C4 obtained following either tracer was <1.0 at baseline and during clamp, indicating that TPI exchange was essentially complete and did not contribute to asymmetric glucose enrichment. Uncorrected and corrected rates of gluconeogenesis were no different (P = not significant) in T2DM vs. ND both at baseline and during clamp. TA correction resulted in equivalent estimates of corrected gluconeogenesis in T2DM and ND that were ~25-35% lower than uncorrected gluconeogenesis both at baseline and during the clamp. The asymmetric enrichment of glucose from ¹³C-gluconeogenic tracers is attributable to TA exchange and can be utilized to correct for TA exchange. In conclusion, TA exchange does not differ between T2DM and ND under fasting or hyperglycemic clamp conditions, and the ²H2O method continues to provide an accurate estimation of gluconeogenesis.