Post-COVID-19 syndrome, inflammation and insulin resistance: a retrospective cohort study

BACKGROUND

COVID-19-induced diabetes is a novel and enigmatic disease. Our aim was to evaluate a possible relationship between post-COVID-19 syndrome (PCS) and increased insulin resistance (IR) in non-diabetic outpatients after mild COVID-19.

METHODS

Repeated measures design. Three evaluations [1E (pre-COVID, baseline), 2E (3 months post-COVID) and 3E (21 months post-COVID)] were performed, directed to PCS+ and PCS- subjects. Triglyceride-glucose (TyG) index ≥8.74 was considered IR, and albumin-to-globulin ratio (AGR) <1.50, inflammation.

RESULTS

We analyzed 112 individuals (median [IQR] age=44 [20] years, 58% women, 36 PCS+, 76 PCS-). PCS+ with very low basal IR (TyG <7.78, lowest quartile) showed a reduced inflammatory burden (basal AGR=1.81 [0.4] vs. 1.68 [0.2] in 2E; P=0.23), and increased TyG across evaluations (from basal 7.62 [0.2] to 8.29 [0.5]; P=0.018]. Conversely, PCS+ subjects with high basal TyG (TyG ≥8.65, highest quartile) did not show significant variations in TyG, but a greater inflammatory load (basal AGR=1.69 [0.3] vs. 1.44 [0.3] in 2E; P=0.10). In multivariable models addressing groups with reduced basal IR (TyG <8.01), PCS has been a consistent predictor for TyG, after adjusting for confounders. Partial correlation and multivariable analyses showed similarities involving acute polysymptomatic COVID-19 and PCS regarding IR.

CONCLUSIONS

PCS was associated with increased IR, being more evident when the baseline degree of IR was very low. PCS and increased IR were separately associated with inflammation. Acute polysymptomatic COVID-19 and PCS could be clinical expressions of underlying inflammatory state, which in turn may also trigger IR.

Post-COVID-19 syndrome, low-grade inflammation and inflammatory markers: a cross-sectional study

OBJECTIVE

Post-COVID syndrome (PCS) is a poorly known entity. An underlying chronic, low-grade inflammation (LGI) has been theorized as a pathophysiological mechanism. Available data on biomarkers in PCS show conflicting results. Our aim was to know whether subjects with PCS present higher levels of inflammatory markers, after a mild COVID-19.

METHODS

Analytical cross-sectional study. Cases of mild COVID-19 in a community setting were included. We collected epidemiological data (age, sex, BMI, smoking, comorbidities), variables of the acute COVID-19 (duration, symptoms), and data at 3 months after the acute phase (symptoms and laboratory test). Serum C-reactive protein (CRP), neutrophil and lymphocyte counts, neutrophil/lymphocyte ratio (NLR), lactate dehydrogenase, ferritin, fibrinogen, and D-dimer levels were analysed. LGI was defined as CRP >0.3 and <1.0 mg/dL. A subject was classified as PCS + if presented signs and symptoms >12 weeks after an infection consistent with COVID-19. Five composite indices (C1-C5) were developed, combining the upper ranges of biomarkers distributions. Multivariate analyses were performed.

RESULTS

We analysed 121 mild COVID-19 cases (mean age = 45.7 years, 56.2% women). Among the acute symptoms, women presented a higher frequency of fatigue (54.4% vs 30.2%; p = .008). PCS affected 35.8% of women and 20.8% of men (p = .07), and the most reported symptoms were fatigue (42.8%), anosmia (40%), ageusia (22.8%), dyspnea (17.1%) and myalgia (11.4%). Neutrophil count, NLR, CRP and fibrinogen showed the best correlations with PCS and were selected to develop the indices. In women PCS+, C1, C3 and C4 indices were more frequently met, while in men PCS+, C2, C5 and CRP were in the range of LGI. Anosmia, ageusia and fatigue were related to higher neutrophil counts, with sex differences. Fibrinogen levels were higher in persistent myalgia (510 ± 82 mg/dL vs 394 ± 87; p = .013). In multivariable analysis, a woman with a neutrophil count above the median, or with fibrinogen level or NLR in the highest tertile, had a 4-5-fold increased risk of prevalent PCS. A man with CRP in the range of LGI, or fibrinogen level or a neutrophil count in the highest tertile, had a 10-17-fold increased risk of prevalent PCS.

CONCLUSIONS

The data obtained in the present cross-sectional study seems to demonstrate a consistent association between PCS and upper ranges of the neutrophil count, NLR, fibrinogen, and CRP in the LGI range. Furthermore, composite indices appear useful in detecting relationships between slight elevations of biomarkers and PCS, and our study identifies relevant sex differences in symptoms and markers regarding the PCS.

Is eating wild rainbow trout safe? The effects of different land-uses on heavy metals content in Chile

Cu, Mn, Fe, Zn, Cd and Pb levels were measured in liver and muscle samples of Rainbow Trout Oncorhynchus mykiss collected from three watersheds with different land-uses: native forest, exotic plantation, and agriculture in Chile, during January, April, July, and October 2012. Cd and Pb levels were not detected in the liver and muscle, probably since they are under the detection limits. Higher metal concentrations (liver-muscle tissues) were detected in samples from agriculture and exotic plantation streams, whereas trout from native forest streams had lower metal concentrations. Higher metal concentrations were detected in liver tissue compared to muscle tissue, and both negatively correlated to the length and weight of the fish. This suggest the liver had higher ability to accumulate Cu, Mn, Fe and Zn compared to muscle tissue. The concentration range of Fe and Zn recorded in the muscle are within the range reported by other authors, whereas Mn and Cu concentrations are higher than reported in the literature. However, at all sites the concentration of selected metals were below the limits permitted by current legislation (FAO), and therefore did not put the human population at risk, suggesting that is eating wild rainbow trout safe in Chile.

Effect of the earthquake-tsunami (Chile, 2010) on toxic metal content in the Chilean abalone mollusc Concholepas concholepas

Toxic metal content were measured in samples of mollusc Concholepas concholepas obtained from the Chilean coast. Samples were collected during two periods, one before and one after the earthquake-tsunami which occurred in the Maule Region, Chile, February 27th, 2010 as a result of an earthquake with a magnitude of 8.8. Quantification of toxic metals in samples of hepatopancreas and muscle tissue was performed using flame atomic absorption spectroscopy. The analytical methodology was validated with certified reference material. The content means measured in muscle tissue for January 2010 were Cu: 10.3; Cr: 0.7; Cd: < 0.1; Mn: 3.6 and Zn: 38.6 µg g^-1 (dry weight). For October 2014, the means were Cu: 8; Cr: 2.4; Cd: < 0.1; Mn: 5.6 and Zn: 45.4 µg g^-1 (dry weight). In hepatopancreas tissue, the content means were Cu: 14.8; Cr: 2.4; Cd: 246.2; Mn: 4.4 and Zn: 1552.9 µg g^-1 (dry weight). For October 2014, the means were Cu: 53.7; Cr: 3.5; Cd: 118; Mn: 13.4 and Zn: 1352.3 µg g^-1 (dry weight). Cd, Cr, Cu, Mn and Zn content in the samples of hepatopancreas were generally higher than those recorded in muscle tissue however they were not always statistically significant. Statistical analysis showed that Cu and Mn content in the post-tsunami period increased in the hepatopancreas tissue. The concentrations of Cd, Cr, Cu, Mn, and Zn measured in the muscular tissue (edible part) of the species Conchalepas concholepas, were lower than the maximum contents allowed by the current legislation (FAO/WHO, 2004; EU, 2001) and its consumption is not a risk to human health.

Simulated FDG-PET studies for the assessment of SUV quantification methods

AIM

To study in detail the accuracy and repeatability of three commonly used methods for SUV estimation in solitary pulmonary nodules.

MATERIAL AND METHODS

We have designed a realistic framework based on simulated FDG-PET acquisitions from an anthropomorphic activity model that included solitary pulmonary nodules (different sizes) of well-known SUV. This framework enables us to compare the SUV values obtained from the reconstructed PET images with the real SUV values. Three commonly used methods (SUVmax, SUVmean and SUV50) were used to estimate the tumor activity.

RESULTS

Our results showed the tumor activity was overestimated using SUVmax and clearly subestimated using SUVmean. Instead, the quantification of SUV50 showed great agreement with the simulated tumor activity and only slight subestimation was found for very small lesions. On the other hand, SUVmean showed better performance than SUV50 in terms of repeatability, providing variabilities below 5% for all tumor sizes and for injected doses as low as 111 MBq.

CONCLUSIONS

Our findings showed that SUV50 provided better performance for estimating accurately tumor SUV values in pulmonary nodules, but SUVmean showed better results in terms of repeatability.

Human erythrocytes and neuroblastoma cells are in vitro affected by sodium orthovanadate

Research on biological influence of vanadium has gained major importance because it exerts potent toxic, mutagenic, and genotoxic effects on a wide variety of biological systems. However, hematological toxicity is one of the less studied effects. The lack of information on this issue prompted us to study the structural effects induced on the human erythrocyte membrane by vanadium (V). Sodium orthovanadate was incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM) and molecular models of the erythrocyte membrane. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. This report presents evidence in order that orthovanadate interacted with red cell membranes as follows: a) in scanning electron microscopy (SEM) studies it was observed that morphological changes on human erythrocytes were induced; b) fluorescence spectroscopy experiments in isolated unsealed human erythrocyte membranes (IUM) showed that an increase in the molecular dynamics and/or water content at the shallow depth of the lipids glycerol backbone at concentrations as low as 50μM was produced; c) X-ray diffraction studies showed that orthovanadate 0.25-1mM range induced increasing structural perturbation to DMPE; d) somewhat similar effects were observed by differential scanning calorimetry (DSC) with the exception of the fact that DMPC pretransition was shown to be affected; and e) fluorescence spectroscopy experiments performed in DMPC large unilamellar vesicles (LUV) showed that at very low concentrations induced changes in DPH fluorescence anisotropy at 18°C. Additional experiments were performed in mice cholinergic neuroblastoma SN56 cells; a statistically significant decrease of cell viability was observed on orthovanadate in low or moderate concentrations.

Detection of novel Human papilloma virus type 82 in laryngeal cancer: case report

Human papilloma virus infection is thought to play a role in laryngeal carcinogenesis; the variable association reported in literature may be due to wide range of HPV genotypes. We report the case of a 51-year-old man affected by laryngeal squamous cell carcinoma; analysis of DNA extracted by cancer cells by an innovative molecular virology assay (INNO-LiPA HPV Genotyping Extra) showed the presence of two high-risk HPV genotypes, HPV-73 and -82. Immunohistochemical examination confirmed positivity for both capsid protein and viral oncogenic protein E7. Such association has never been reported in literature so far, and a brief discussion on the importance of assessing HPV status in laryngeal cancer is provided.