Stability of human salivary extracellular vesicles containing dipeptidyl peptidase IV under simulated gastrointestinal tract conditions

BackgroundExtracellular vesicles (EVs) have been isolated from various sources, including primary and cultured cell lines and body fluids. Previous studies, including those conducted in our laboratory, have reported the stability of EVs under various storage conditions.MethodsEVs from human whole saliva were separated via size-exclusion chromatography. To simulate the effects of gastric or intestinal fluids on the stability of EVs, pepsin or pancreatin was added to the samples. Additionally, to determine the effect of bile acids, sodium cholate was added. The samples were then subjected to western blotting, dynamic light scattering, and transmission electron microscopy analyses. In addition, the activity of dipeptidyl peptidase (DPP) IV retained in the samples was examined to monitor the stability of EVs.ResultsUnder acidic conditions, with pepsin mimicking the milieu of the stomach, the EVs remained stable. However, they partially lost their membrane integrity in the presence of pancreatin and sodium cholate, indicating that they may be destabilized after passing through the duodenum. Although several associated proteins, such as mucin 5B and CD9 were degraded, DPP IV was stable, and its activity was retained under the simulated gastrointestinal conditions.ConclusionOur data indicate that although EVs can pass through the stomach without undergoing significant damage, they may be disrupted in the intestine to release their contents. The consistent delivery of active components such as DPP IV from EVs into the intestine might play a role in the efficient modulation of homeostasis of the signal transduction pathways occurring in the gastrointestinal tract.     

High-resolution structure of phosphoketolase from Bifidobacterium longum determined by cryo-EM single-particle analysis

In bifidobacteria, phosphoketolase (PKT) plays a key role in the central hexose fermentation pathway called “bifid shunt.” The three-dimensional structure of PKT from Bifidobacterium longum with co-enzyme thiamine diphosphate (ThDpp) was determined at 2.1 Å resolution by cryo-EM single-particle analysis using 196,147 particles to build up the structural model of a PKT octamer related by D₄ symmetry. Although the cryo-EM structure of PKT was almost identical to the X-ray crystal structure previously determined at 2.2 Å resolution, several interesting structural features were observed in the cryo-EM structure. Because this structure was solved at relatively high resolution, it was observed that several amino acid residues adopt multiple conformations. Among them, Q546–D547–H548–N549 (the QN-loop) demonstrate the largest structural change, which seems to be related to the enzymatic function of PKT. The QN-loop is at the entrance to the substrate binding pocket. The minor conformer of the QN-loop is similar to the conformation of the QN-loop in the crystal structure. The major conformer is located further from ThDpp than the minor conformer. Interestingly, the major conformer in the cryo-EM structure of PKT resembles the corresponding loop structure of substrate-bound Escherichia coli transketolase. That is, the minor and major conformers may correspond to “closed” and “open” states for substrate access, respectively. Moreover, because of the high-resolution analysis, many water molecules were observed in the cryo-EM structure of PKT. Structural features of the water molecules in the cryo-EM structure are discussed and compared with water molecules observed in the crystal structure.     

Proteins in Tumor-Derived Plasma Extracellular Vesicles Indicate Tumor Origin

Cancer-derived extracellular vesicles (EVs) promote tumorigenesis, premetastatic niche formation, and metastasis via their protein cargo. However, the proteins packaged by patient tumors into EVs cannot be determined in vivo because of the presence of EVs derived from other tissues. We therefore developed a cross-species proteomic method to quantify the human tumor-derived proteome of plasma EVs produced by patient-derived xenografts of four cancer types. Proteomic profiling revealed individualized packaging of novel protein cargo, and machine learning accurately classified the type of the underlying tumor.     

In-vivo hyperglycemic,antioxidant, histopathological changes,and simultaneous measurement of kaempferol verified by high-performance thin layer chromatography of Setaria italica in streptozotocin -induced diabetic rats

BackgroundSetaria italica (common name- foxtail, kangni) is one of the major food crops which is prominently cultivated in southern regions of India and in certain regions of Uttar Pradesh. Besides the crop’s consumption as a general source of carbohydrate rich cereal, the seeds of the crop are comprised of more fiber. So, it is recommended to add in the dietary supplementation of the diabetic people across the country.ObjectiveIn this paper, it intends to investigate the antidiabetic activity and antioxidant activity of S. italica (foxtail millet) seeds in diabetic rats.MethodsThe six genotypes of foxtail millets (S. italica) namely Kangni-1, Kangni-4, Kangni-5, Kangni-6, Kangni-7 & Kangni-10 respectively were subjected to in vitro investigations via. comprehensive metabolic panel (CMP) involving blood glucose study, Kidney & Liver function test, and antioxidant study (Catalase test; Glutathione S-transferase (GST); Superoxide Dismutase (SOD); glutathione (GSH); hiobarbituric acid reactive substances (TBARS) & Glutathione peroxidase (GPx) and were performed in vivo animal investigations in Wistar rats. The STZ induced diabetic rats were fed with doses of different S. italica seed aqueous extract to evaluate its anti-hyperglycemic activity by oral administration of SISAE. Further, it was compared with Glibenclamide which acts as one of the standard oral hypoglycemic agents.ResultsFrom achieved outcomes, a significant fall of blood glucose level (70%) produced 300 mg SISAE/kg b.w. after 6 h of extract administration. However, no change could be produced by these doses of the SISAE in normal rats’ blood glucose levels. A significant fall in glucose level along with significant glycemic control by lower HbA1c levels was observed in diabetic treated rats after 3 weeks of treatment with 300 mg of SISAE/kg b.w./day when comparing to untreated diabetic rats. Among these five genotypes of S. italica, the differences in the glycemic index were found. a significant fall could be found in blood glucose levels of Wistar rats, when every experimental rat was incorporating with the extract of different genotypes of Setaria italica L. Beauv than the rats treated with Glibenclamide in every 7 days of interval. The level of catalase, SOD, GST, GPx, GSH and TBARS showed variation while the rats were fed with the extract of S. italica in the liver test of rats. In kidney function test, the result shows that there is significant relationship between foxtail extract and kidney function of STZ induced diabetes rats. They show the change in their serum creatinine level, serum urea and serum uric acid.ConclusionThe result obtained from the study shows that the extract of S. italica seeds is capable for the hypolipidemic and antihyperglycemic activities, thereby, they serve as one of the good sources for herbal medicinal items.     

The impact of left common pulmonary vein on cryoballoon ablation of atrial fibrillation. A meta-analysis

IntroductionConflicting results regarding the impact of left common pulmonary vein (LCPV) on clinical outcome of atrial fibrillation (AF) ablation with cryoballoon technology have been reported.MethodsWe systematically searched PubMed and Cochrane library for articles that compared the arrhythmia recurrence rate after cryoballoon ablation between patients with normal pattern PVs and patients with LCPV. Studies of first ablation for persistent and paroxysmal AF using the 28 mm Arctic Front Advance, Medtronic cryoballoon (CB-A) reporting clinical success rates at a mean follow-up of ≥12 months were included. Data were analyzed by applying a random effects model.ResultsA total of 5 studies with a total of 1178 patients met our predefined inclusion criteria. After a mean follow-up of 18.4 months, the overall success rate of CB-A ablation among patients with persistent and paroxysmal AF was 57%; in the LCPV group the success rate was 46% and in the normal anatomical pattern group it was 61%. No significant heterogeneity was noted among the studies (I² = 35.8%; Q (df = 3) = 6.23 p-value = 0.18). Arrhythmia recurrence after CB-A ablation was not statistically significant between the two groups (LogOR 0.24; 95% CI [-0.16-0.63]; p-value = 0.23). No significant difference in PNI was observed between the two groups (p-value = 0.693).ConclusionThe presence of LCPV does not affect the long-term outcome of paroxysmal and persistent atrial fibrillation ablation with 28 mm CB-A compared to normal left PVs pattern.     

Mass Spectrometry Identification of Biomarkers in Extracellular Vesicles From Plasmodium vivax Liver Hypnozoite Infections

Latent liver stages termed hypnozoites cause relapsing Plasmodium vivax malaria infection and represent a major obstacle in the goal of malaria elimination. Hypnozoites are clinically undetectable, and presently, there are no biomarkers of this persistent parasite reservoir in the human liver. Here, we have identified parasite and human proteins associated with extracellular vesicles (EVs) secreted from in vivo infections exclusively containing hypnozoites. We used P. vivax-infected human liver-chimeric (huHEP) FRG KO mice treated with the schizonticidal experimental drug MMV048 as hypnozoite infection model. Immunofluorescence-based quantification of P. vivax liver forms showed that MMV048 removed schizonts from chimeric mice livers. Proteomic analysis of EVs derived from FRG huHEP mice showed that human EV cargo from infected FRG huHEP mice contain inflammation markers associated with active schizont replication and identified 66 P. vivax proteins. To identify hypnozoite-specific proteins associated with EVs, we mined the proteome data from MMV048-treated mice and performed an analysis involving intragroup and intergroup comparisons across all experimental conditions followed by a peptide compatibility analysis with predicted spectra to warrant robust identification. Only one protein fulfilled this stringent top-down selection, a putative filamin domain-containing protein. This study sets the stage to unveil biological features of human liver infections and identify biomarkers of hypnozoite infection associated with EVs.     

Patterns of treatment failure for PD-(L)1 refractory extensive-stage small cell lung cancer in continued PD-(L)1 treatment

BackgroundAlthough immunotherapy greatly extends overall survival (OS) of patients with extensive-stage small cell lung cancer (ES-SCLC), a number of patients develop immunotherapy resistance (IR). Patterns of failure in ES-SCLC are not clarified. Our study aims to explore the clinical pattern of IR and prognostic factors for these patients.MethodsThe study was conducted from 117 ES-SCLC patients with immunotherapy between 2018 and 2022. Chi-square tests and Fishers' exact tests was used to explore failure patterns in different populations. Survival analyses of different progression patterns and subsequent treatment regimens were conducted by Kaplan–Meier curves and log-rank test.Results86 (73.5%) patients experienced IR. The patients with smoking (never smoker vs. current or ex-smoker, 59.5 % vs. 81.3%, P = 0.010), liver metastasis (extrahepatic metastasis vs. intrahepatic metastasis, 73.6 % vs. 90.9%, P = 0.050), and distant metastasis status (no distant metastasis vs. distant metastasis, 39.1 % vs. 81.9%, P<0.001) were associated with IR rates. Liver progression had a lower incidence in 1st line immunotherapy (1st line vs. ≥2nd lines, 14.0 % vs. 41.7%, P = 0.004) and a higher incidence in multiple progression (multiple progression vs. Oligo-progression, 39.4 % vs. 17.0%, P = 0.021). Cranial (41.7 % vs. 16.1%, P = 0.012) and distant lymph node (16.7 % vs. 3.2%, P = 0.049) progression were the main failure model for acquired IR in comparison to primary IR. Patients with new lesion progression only (17.73 vs. 9.17 months, P = 0.013) and non-hepatic progression (14.23 vs. 11.67 months, P = 0.042) had a longer OS. Patients in cross-line immunotherapy after IR had a favourable prognosis (17.07 vs. 11.93 months, P = 0.007).ConclusionThe most common failure pattern of immunotherapy for ES-SCLC was lung and regional lymph node progression. Brain and liver progression were the most common extra thoracic failure sites for 1st line and 2nd and more lines immunotherapy, respectively. There was a higher probability of primary IR in 2 lines and above immunotherapy. Patients with new only progression site and cross-line rechallenge immunotherapy had a better prognosis.     

Impact of baseline telomere length on survival and chemotherapy related toxicity in breast cancer patients receiving (neo)adjuvant anthracycline containing chemotherapy

PurposeThe aim of this study is to assess baseline mean leukocyte telomere length (TL) as a potential predictive factor for chemotherapy toxicity and a prognostic marker for long-term outcome in early breast cancer (BC) patients.Methods445 BC patients were selected, diagnosed between 2007 and 2010 with early BC and treated with (neo)adjuvant fluorouracil, epirubicin and cyclophosphamide (FEC) or with FEC and Docetaxel (FEC-D). RT-qPCR was performed on germline DNA samples collected at diagnosis before any treatment, to measure mean leukocyte TL. Uni- and multivariable logistic regression or Cox proportional hazard regression analyses were carried out to assess correlation between baseline TL and toxicity parameters (derived from the medical chart) or longer-term outcome.ResultsBaseline TL correlated with age as expected (p = 0.005), but not with febrile neutropenia (n = 97), left ventricular ejection fraction >10% decrease (n = 17) nor other toxicity endpoints measured (all p > 0.05). TL was neither associated with overall survival, breast cancer specific survival or distant disease-free survival (all p > 0.05).ConclusionsBaseline TL is not associated with chemotherapy-related toxicity nor long-term outcome in BC patients.     

Proteomic analysis of hypoxia and non-hypoxia secretome mesenchymal stem-like cells from human breastmilk

IntroductionBreastmilk contains proteins and cells which have stem cell properties. The human breastmilk stem cell mimick mesenchymal stem cells and expresses pluripotency genes. The protein level of breastmilk is high in colostrum and gradually subsides in the first year of lactation. The mesenchymal stem cells from breastmilk can be an alternative source of stem cells that can potentially affect cardiovascular therapy. This study aimed to identify the proteomic analysis of secretome mesenchymal stem-like cells under hypoxia compared to non-hypoxia from human breastmilk stem cells.Material and methodsThe human breastmilk was collected from six healthy breastfeeding women and transported to the laboratory under aseptic conditions. The breastmilk cells were isolated then cultured. After 72 h, the human breastmilk stem cells reached confluence then cleaned up and isolated in serum-free media (spheroid) to allow serial passaging every 48 h. The acquisition stem cell was made with flow cytometry. The cells were divided into hBSC secretomes under hypoxia (A) and non-hypoxia (B) and analyzed for LC-MS to identify the peptide structure.ResultsThe human breastmilk cells contained several mesenchymal stem-like cells in density 2.4 × 10⁶ cell/mL for hypoxia and 2 × 10⁶ cell/mL for non-hypoxia conditions. The human breastmilk stem cell surface markers derived from the third cell passage process were 93.77% for CD44, 98.69% for CD73, 88.45% for CD90, and 96.30% for CD105. The protein level of secretome mesenchymal stem -like cells under hypoxia was measured at 5.56 μg/mL and 4.28 μg/mL for non-hypoxia. The liquid chromatography-mass spectrometry analysis identified 130 and 59 peptides from hypoxia and non-hypoxia of the human breastmilk stem cell secretome sequentially. Some important proteomics structures were found in the hypoxic human breastmilk stem cell secretome, such as transforming growth factor-β, VE-cadherin, and caspase.ConclusionThe human breastmilk cells contain mesenchymal stem-like cells and a high concentration of CD44, CD73, CD90, and CD105 as surface markers at third passage culture. The hypoxic hBSC secretome produces a higher protein level compare to non-hypoxia. The transforming growth factor -β was found in the hypoxic hBSC secretome as a modulator of VEGF-mediated angiogenesis.     

Impact of iterative reconstructions on image quality and detectability of focal liver lesions in low-energy monochromatic images

PurposeTo assess the impact of iterative reconstructions on image quality and detectability of focal liver lesions in low-energy monochromatic images from a Fast kV-Switching Dual Energy CT (KVSCT) platform.MethodsAcquisitions on an image-quality phantom were performed using a KVSCT for three dose levels (CTDI_vol:12.72/10.76/8.79 mGy). Raw data were reconstructed for five energy levels (40/50/60/70/80 keV) using Filtered Back Projection (FBP) and four levels of ASIR (ASIR30/ASIR50/ASIR70/ASIR100). Noise power spectrum (NPS) and task-based transfer function (TTF) were measured before computing a Detectability index (d′) to model the detection task of liver metastasis (LM) and hepatocellular carcinoma (HCC) as function of keV.ResultsFrom 40 to 70 keV, noise-magnitude was reduced on average by −68% ± 1% with FBP; −61% ± 3% with ASIR50 and −52% ± 6% with ASIR100. The mean spatial frequency of the NPS decreased when the energy level decreased and the iterative level increased. TTF values at 50% decreased as the energy level increased and as the percentage of ASIR increased. The detectability of both lesions increased with increasing dose level and percentage of ASIR. For the LM, d′ peaked at 70 keV for all reconstruction types, except for ASIR70 at 12.72 mGy and ASIR100, where d' peaked at 50 keV. For HCC, d’ peaked at 60 keV for FBP and ASIR30 but peaked at 50 keV for ASIR50, ASIR70 and ASIR100.ConclusionsUsing percentage of ASIR above 50% at low-energy monochromatic images could limit the increase of noise-magnitude, benefit from spatial resolution improvement and hence enhance detectability of subtle low contrast focal liver lesions such as HCC.     

Comparison of Preoperative Alpha-blockade for Resection of Paraganglioma and Pheochromocytoma

ObjectivePhenoxybenzamine (nonselective, noncompetitive alpha-blocker) is the preferred drug for preoperative treatment of pheochromocytoma, but doxazosin (selective, competitive alpha-blocker) may be equally effective. We compared the efficacy of doxazosin vs phenoxybenzamine.MethodsWe conducted a prospective study of patients undergoing pheochromocytoma or paraganglioma resection by randomizing pretreatment with phenoxybenzamine or doxazosin at a single tertiary referral center. The high cost of phenoxybenzamine led to high crossover to doxazosin. Randomization was halted, and a consecutive historical cohort of phenoxybenzamine patients was included for a case-control study design. The efficacy of alpha-blockade was assessed with preinduction infusion of incremental doses of phenylephrine. The primary outcomes were mortality, cardiovascular complications, and intensive care unit admission. The secondary outcomes were hemodynamic instability index (proportion of operation outside of hemodynamic goals), adequacy of blockade by the phenylephrine titration test, and drug costs.ResultsTwenty-four patients were prospectively enrolled (doxazosin, n = 20; phenoxybenzamine, n = 4), and 15 historical patients treated with phenoxybenzamine were added (total phenoxybenzamine, n = 19). No major cardiovascular complications occurred in either group. The phenylephrine dose-response curves showed less blood pressure rise in the phenoxybenzamine than in the doxazosin group (linear regression coefficient = 0.008 vs 0.018, P = .01), suggesting better alpha-blockade in the phenoxybenzamine group. The median hemodynamic instability index was 14% vs 13% in the phenoxybenzamine and doxazosin groups, respectively (P = .56). The median highest daily cost of phenoxybenzamine was $442.20 compared to $5.06 for doxazosin.ConclusionPhenoxybenzamine may blunt intraoperative hypertension better than doxazosin, but this difference did not translate to fewer cardiovascular complications and is offset by a considerably increased cost.     

Ergonomics for surgeons – prototype of an external surgeon support system reduces muscular activity and fatigue

BackgroundSince the unergonomic postures cannot be changed during a surgery, it seems reasonable to externally support the surgeon's posture in order to relieve the musculature. To evaluate this matter, we conducted a pilot study to investigate if a prototype of an external surgeon support system (S3) relieves the musculature in an objectively measurable manner.MethodsSimultaneous surface electromyography (EMG) was used alongside a combination of a laser Doppler flowmeter and a tissue spectrometer to record back and leg muscles during a simulated surgical situation.FindingsWith S3, muscle activity was significantly lower (p < 0.05) and also fatigue decreased when compared to without S3. Muscle blood flow and oxygenation were relatively close to baseline with S3, but increased without S3.InterpretationAn ergonomic S3 is a possible approach to reduce muscle activity and fatigue and may therefore prevent chronic back pain amongst surgeons in the long term.     

Intravoxel incoherent motion radiomics nomogram for predicting tumor treatment responses in nasopharyngeal carcinoma

BackgroundIntravoxel incoherent motion (IVIM) plays an important role in predicting treatment responses in patient with nasopharyngeal carcinoma (NPC). The goal of this study was to develop and validate a radiomics nomogram based on IVIM parametric maps and clinical data for the prediction of treatment responses in NPC patients.MethodsEighty patients with biopsy-proven NPC were enrolled in this study. Sixty-two patients had complete responses and 18 patients had incomplete responses to treatment. Each patient received a multiple b-value diffusion-weighted imaging (DWI) examination before treatment. Radiomics features were extracted from IVIM parametric maps derived from DWI image. Feature selection was performed by the least absolute shrinkage and selection operator method. Radiomics signature was generated by support vector machine based on the selected features. Receiver operating characteristic (ROC) curves and area under the ROC curve (AUC) values were used to evaluate the diagnostic performance of radiomics signature. A radiomics nomogram was established by integrating the radiomics signature and clinical data.ResultsThe radiomics signature showed good prognostic performance to predict treatment response in both training (AUC = 0.906, P<0.001) and testing (AUC = 0.850, P<0.001) cohorts. The radiomic nomogram established by integrating the radiomic signature with clinical data significantly outperformed clinical data alone (C-index, 0.929 vs 0.724; P<0.0001).ConclusionsThe IVIM-based radiomics nomogram provided high prognostic ability to treatment responses in patients with NPC. The IVIM-based radiomics signature has the potential to be a new biomarker in prediction of the treatment responses and may affect treatment strategies in patients with NPC.     

Associations of Urinary Polycyclic Aromatic Hydrocarbons With Bone Mineral Density at Specific Body Sites in U.S. Adults,National Health and Nutrition Examination Survey 2001 to 2004

ObjectiveWe aimed to analyze the association between certain types of urinary polycyclic aromatic hydrocarbons (PAHs) and bone mineral density (BMD) at specific sites of the body.MethodsA total of 2978 eligible participants from the National Health and Nutrition Examination Survey 2001 to 2004 were included in this study. Data of 8 urinary PAHs and BMDs of 3 skeleton sites and the total body were analyzed. Univariate and multivariate linear regression analyses were performed to explore the association between urinary PAHs and BMDs. Subgroup analyses stratified by sex and body mass index were also performed.ResultsAfter adjustment for all confounders, elevated 3-fluorene (β = 0.046; 95% confidence intervals [CIs], 0.007-0.084) and 2-fluorene (β = 0.054; 95% CI, 0.007-0.100) levels were associated with greater left arm BMD, whereas no statistical differences were observed in the relationship between other PAHs and BMDs (all P > .05). Higher 3-fluorene and 2-fluorene levels were still associated with increased left arm BMD in men (P < .05), whereas the higher 2-phenanthrene level was related to decreased left arm BMD (β = ?0.062; 95% CI, ?0.105 to ?0.019), right arm BMD (β = ?0.059; 95% CI, ?0.091 to ?0.027), and total BMD (β = ?0.065; 95% CI, ?0.119 to ?0.012) in women. Similar results were also found in different body mass index populations (all P < .05).ConclusionCertain urinary PAHs are associated with BMDs at specific body sites. Future studies are needed to illustrate the mechanisms behind the association to establish a causal relationship.     

What Is the Optimal Speed of correction of the Hyperosmolar Hyperglycemic State in Diabetic Ketoacidosis? An Observational Cohort Study of U.S. Intensive Care Patients

ObjectiveThe international guidelines for the treatment of diabetic ketoacidosis (DKA) advise against rapid changes in osmolarity and glucose; however, the optimal rates of correction are unknown. We aimed to evaluate the rates of change in tonicity and glucose level in intensive care patients with DKA and their relationship with mortality and altered mental status.MethodsThis is an observational cohort study using 2 publicly available databases of U.S. intensive care patients (Medical Information Mart for Intensive Care-IV and Electronic Intensive Care Unit), evaluating adults with DKA and associated hyperosmolarity (baseline Osm ≥300 mOsm/L). The primary outcome was hospital mortality. The secondary neurologic outcome used a composite of diagnosed cerebral edema or Glasgow Coma Scale score of ≤12. Multivariable regression models were used to control for confounding factors.ResultsOn adjusted analysis, patients who underwent the most rapid correction of up to approximately 3 mmol/L/hour in tonicity had reduced mortality (n = 2307; odds ratio [OR], 0.21; overall P < .001) and adverse neurologic outcomes (OR, 0.44; P < .001). Faster correction of glucose levels up to 5 mmol/L/hour (90 mg/dL/hour) was associated with improvements in mortality (n = 2361; OR, 0.24; P = .020) and adverse neurologic events (OR, 0.52; P = .046). The number of patients corrected significantly faster than these rates was low. A maximal hourly rate of correction between 2 and 5 mmol/L for tonicity was associated with the lowest mortality rate on adjusted analysis.ConclusionBased on large-volume observational data, relatively rapid correction of tonicity and glucose level was associated with lower mortality and more favorable neurologic outcomes. Avoiding a maximum hourly rate of correction of tonicity >5 mmol/L may be advisable.     

Genotypic and phenotypic characterization of industrial autochthonous Saccharomyces cerevisiae for the selection of well-adapted bioethanol-producing strains

In northwestern Argentina, sugarcane-derived industrial fermentation is being extensively used for bioethanol production, where highly adaptive native strains compete with the baker's yeast Saccharomyces cerevisiae traditionally used as starter culture. Yeast populations of 10 distilleries from Tucumán (Argentina) were genotypic and phenotypic characterized to select well-adapted bioethanol-producing autochthonous strains to be used as starter cultures for the industrial production of bioethanol fuel. From the 192 isolates, 69.8% were identified as S. cerevisiae, 25.5% as non-Saccharomyces, and 4.7% as Saccharomyces sp. wild yeasts. The majority of S. cerevisiae isolates (68.5%) were non-flocculating yeasts, while the flocculating strains were all obtained from the only continuous fermentation process included in the study. Simple Sequence Repeat analysis revealed a high genetic diversity among S. cerevisiae genotypes, where all of them were very different from the original baker's strain used as starter. Among these, 38 strains multi-tolerant to stress by ethanol (8%), temperature (42.5 °C) and pH (2.0) were obtained. No major differences were found among these strains in terms of ethanol production and residual sugars in batch fermentation experiments with cell recycling. However, only 10 autochthonous strains maintained their viability (more than 80%) throughout five consecutive cycles of sugarcane-based fermentations. In summary, 10 autochthonous isolates were found to be superior to baker's yeast used as starter culture (S. cerevisiae Calsa) in terms of optimal technological, physiological and ecological properties. The knowledge generated on the indigenous yeast populations in industrial fermentation processes of bioethanol-producing distilleries allowed the selection of well-adapted bioethanol-producing strains.     

Comparative Study of Initial Post-Therapeutic 131I Single-Photon Emission Computed Tomography/Computed Tomography and Reoperation for the Detection of Residual Lymph Node Metastasis in Patients With Papillary Thyroid Cancer

ObjectiveTo assess the diagnostic performance of initial post-therapeutic ¹³¹I single-photon emission computed tomography/computed tomography (SPECT/CT) compared with that of reoperation in detecting residual lymph node metastasis (LNM).MethodsPatients with iodine-avid LNM detected on the initial post-therapeutic ¹³¹I SPECT/CT and who underwent reoperative dissection within 6 months were included. LNMs (numbers and locations) detected via both methods were compared. The American Thyroid Association dynamic risk stratification was performed for patients receiving second radioactive iodine therapy after reoperation.ResultsFifty-three patients with 95 iodine-avid LNMs detected by ¹³¹I SPECT/CT were enrolled. Fifty-one (96.2%) patients had 212 LNMs confirmed by reoperation (P = .004). The sensitivity and specificity of ¹³¹I SPECT/CT in detecting LNM were 44.8% (95/212) and 91.6% (87/95), respectively. The location frequency of residual LNMs found by ¹³¹I SPECT/CT was similar to that of reoperation (P = .057). Thirty-two patients received a second radioactive iodine treatment, and 6 (18.8%) patients still had residual iodine-avid LNM on SPECT/CT. Therapeutic response was evaluated by American Thyroid Association dynamic risk stratification in 16 patients. The number of patients with structural incomplete response, biochemical incomplete response, indeterminate response, and excellent response was 4 (23.5%), 4 (23.5%), 5 (29.4%), and 3 (17.6%), respectively.Conclusion¹³¹I SPECT/CT has high specificity but relatively low sensitivity in detecting all residual LNMs. Approximately 80% of patients were rendered structurally disease free after reoperation.     

Relationship between ablation index and myocardial biomarkers after radiofrequency catheter ablation for atrial fibrillation

BackgroundFurther in-vivo evidence is needed to support the usefulness of ablation index (AI) in guiding atrial fibrillation (AF) ablation. We aimed at evaluating the relationship between AI and other lesion indicators and the release of myocardial-specific biomarkers following radiofrequency AF ablation.MethodsForty-six patients underwent a first-time radiofrequency AF ablation and were prospectively enrolled in this study. Pulmonary vein isolation was performed by six experienced electrophysiologists with a point-by-point approach, guided by strict Visitag criteria and consistent AI target values. Myocardial-specific biomarkers troponin T and creatine kinase myocardial band were measured after 6 (TnT6 and CKMB6) and 20 h (TnT20 and CKMB20) following sheath removal. Ablation duration, impedance drop (ID), force-time integral (FTI) and AI were registered automatically and analyzed offline.ResultsTnT release was 985 ± 495 ng/L and 1038 ± 461 ng/L (p = ns) while CKMB release was 7.3 ± 2.7 μg/L and 6.5 ± 2.1 μg/L (p < 0.001) at 6 and 20 h respectively. Ablation duration, ID, FTI and AI were all significantly correlated with the release of myocardial-specific biomarkers both at 6 and 20 h. Ablation index showed the highest degree of correlation with TnT6, TnT20, CKMB6 and CKMB20 (Pearson's R 0.69, 0.69, 0.61, 0.64 respectively, p < 0.001). Multiple regression analysis demonstrated that AI had the strongest association with TnT6, TnT20, CKMB6 and CKMB20 (β 0.43, β 0.71, β 0.44 and β 0.43 respectively).ConclusionAblation index appears as the strongest lesion indicator as measured by the release of myocardial-specific biomarkers following radiofrequency catheter ablation for AF.     

Clinical,Hormonal, and Genetic Characteristics of 5α-Reductase Type 2 Deficiency in 103 Chinese Patients

Objective5α-Reductase type 2 (5α-RD2) deficiency causes variable degrees of undervirilization in patients. The correlation between its genotype and phenotype is unclear.MethodsWe retrospectively evaluated 103 patients with 46,XY disorders of sex development who were diagnosed with 5α-RD2 deficiency.ResultsThe prevalence of female sex assignment (P = .008) and the incidences of cryptorchidism (P = .0003) and bifid scrotum (P = .0002) in the non-p.R227Q variant group were higher, but there were no significant differences in the incidences of hypospadias and isolated microphallus. The external masculinization score in the non-p.R227Q variant group was lower than that in the homozygous p.R227Q variant (P = .019) and compound heterozygous p.R227Q variant groups (P = .013). The level of anti-Mullerian hormone in the non-p.R227Q variant group was lower than that in the homozygous p.R227Q variant (P < .001) and compound heterozygous p.R227Q variant groups (P = .006). The testosterone-to-dihydrotestosterone ratio of the homozygous p.R227Q variant group was higher than that of the non-p.R227Q variant (P = .018) and compound heterozygous p.R227Q variant groups (P = .029). Twenty-three reportedly pathogenic variants and 11 novel steroid 5α-reductase 2 (SRD5A2) variants were identified.ConclusionCompared with patients without p.R227Q, patients with p.R227Q exhibited higher external masculinization scores and anti-Mullerian hormone expression, a lower prevalence of female sex assignment, and lower incidences of cryptorchidism and bifid scrotum. We identified 23 reportedly pathogenic SRD5A2 variants and 11 novel SRD5A2 variants that led to 5α-RD2 deficiency. We established a genotype-phenotype correlation, and patients with p.R227Q showed a relatively mild phenotype.     

Copper and mercury induced oxidative stresses and antioxidant responses of Spirodela polyrhiza (L.) Schleid

Duckweed is recognized as a phytoremediation aquatic plant due to the production of large biomass and a high level of tolerance in stressed conditions. A laboratory experiment was conducted to investigate antioxidant response and mechanism of copper and mercury tolerance of S. polyrhiza (L.) Schleid. To understand the changes in chlorophyll content, MDA, proline, and activities of ROS-scavenging enzymes (SOD, CAT, GPOD) during the accumulation of Cu⁺² and Hg⁺², S. polyrhiza were exposed to various concentrations of Cu⁺² (0.0–40 μM) and Hg⁺² (0.0–0.4 μM). antioxidant activity initially indicated enhancing trend with application of 10 μM Cu⁺²; 0.2 μM Hg⁺² (SOD), of 20 μM Cu⁺²; 0.2 μM Hg⁺² (CAT) and of 10 μM Cu⁺²;0.2 μM Hg⁺² (GPOD) and then decreased consistently up to 40 μM Cu⁺² and 0.4 μM Hg⁺². In the experiment chlorophyll and frond multiplication initially showed increasing tendency and decreased gradually with the application of increased metal concentration. Application of heavy metal has constantly enhanced proline and MDA content while the maximum increase was observed with the application of 40 μM Cu; 0.4 μM Hg for proline and MDA respectively. The upregulation of antioxidant enzymes and proline reveals that S. polyrhiza has strong biochemical strategies to deal with the heavy metal toxicity induced by the accumulation of Cu⁺² and Hg⁺².