An analysis from the CAPACITY database of outcomes of preoperative embolization before carotid body tumor surgery compared with resection alone.

OBJECTIVE: There is no definitive consensus on the impact of preoperative embolization on carotid body tumor (CBT) treatment. The objective of this study was to compare surgical outcomes of patients who underwent preoperative embolization before CBT resection vs patients who underwent resection alone. METHODS: The CAPACITY registry included 1432 patients with CBT from 11 medical centers in four different countries. The group of patients undergoing CBT resection with preoperative embolization was matched in a 1:6 ratio from a pool of patients from the CAPACITY database, using a generated propensity score with patients who did not underwent preoperative embolization. RESULTS: A total of 553 patients were included for analysis. Mean patient age was 56.23 ± 12.22 years. Patients were mostly female (n = 469; 84.8%). Bilateral CBT was registered in 60 patients (10.8%). Seventy-nine patients (14.3%) underwent preoperative embolization. Embolized patients had larger CBT sizes than non-embolized patients (33.8 mm vs 18.4 mm; P = .0001). Operative blood loss was lower in the embolized group compared with the non-embolized group (200 mL vs 250 mL; P = .031). Hematomas were more frequent in the non-embolized group (0% vs 2.7%; P = .044). Operative time, rates of stroke, cranial nerve injuries, and death were not statistically significant between groups. CONCLUSIONS: Embolization before CBT resection was associated with significantly lower blood loss and lower neck hematomas than patients who underwent resection alone. Operative time, stroke, cranial nerve injuries, and death were similar between groups.

Risk Factors for Stroke After Carotid Paraganglioma Surgery.

BACKGROUND: The Carotid Paraganglioma Cooperative International Registry (CAPACITY) is an international registry composed of 1,432 patients with carotid body tumors (CBT) from 11 centers from 4 countries. The aim of this study was to identify risk factors for patients who presented stroke after carotid paraganglioma resection. METHODS: Clinical characteristics and demographics of patients who presented transoperatively and postoperatively stroke from the CAPACITY database were retrospectively gathered. Regression analysis was performed using single logistic regression with Omnibus' test for possible factors that might contribute to present stroke. RESULTS: Out of 1,432 patients, 8 (0.5%) female patients presented stroke. Median age was 53 years (range: 41-70 years). Six strokes occurred transoperatively, diagnosed clinically in the immediate postoperative period. Of them, none of the patients received any further treatment. Three of them died on postoperative day 2, 3, and 4. Two patients developed stroke during the first 24 postoperative hours, patients showed dysarthria, and aphasia. One of them was reintervened with thrombectomy due to thrombosis of the common carotid artery the other patient was treated conservatively. Median follow-up was 16 months (range: 2-72 months). Single logistic regression analysis revealed a history of diabetes mellitus (odds ratio (OR) 7.62), carotid artery disease (OR 17.51), and vascular lesion (OR 2.37) to have significantly increased odds of stroke during CBT surgery. CONCLUSIONS: In the present study history of diabetes mellitus, carotid artery disease, and vascular lesion had increased odds of stroke during CBT surgery. Findings are limited by low event rate and even larger cohorts are needed to fully define preventive preoperative strategies for preventing stroke.

Recent Developments in Biomarkers for Diagnosis and Screening of Type 2 Diabetes Mellitus.

PURPOSE OF REVIEW: Diabetes mellitus is a complex, chronic illness characterized by elevated blood glucose levels that occurs when there is cellular resistance to insulin action, pancreatic ß-cells do not produce sufficient insulin, or both. Diabetes prevalence has greatly increased in recent decades; consequently, it is considered one of the fastest-growing public health emergencies globally. Poor blood glucose control can result in long-term micro- and macrovascular complications such as nephropathy, retinopathy, neuropathy, and cardiovascular disease. Individuals with diabetes require continuous medical care, including pharmacological intervention as well as lifestyle and dietary changes. RECENT FINDINGS: The most common form of diabetes mellitus, type 2 diabetes (T2DM), represents approximately 90% of all cases worldwide. T2DM occurs more often in middle-aged and elderly adults, and its cause is multifactorial. However, its incidence has increased in children and young adults due to obesity, sedentary lifestyle, and inadequate nutrition. This high incidence is also accompanied by an estimated underdiagnosis prevalence of more than 50% worldwide. Implementing successful and cost-effective strategies for systematic screening of diabetes mellitus is imperative to ensure early detection, lowering patients' risk of developing life-threatening disease complications. Therefore, identifying new biomarkers and assay methods for diabetes mellitus to develop robust, non-invasive, painless, highly-sensitive, and precise screening techniques is essential. This review focuses on the recent development of new clinically validated and novel biomarkers as well as the methods for their determination that represent cost-effective alternatives for screening and early diagnosis of T2DM.

Microcarrier-based stem cell bioprocessing: GMP-grade culture challenges and future trends for regenerative medicine.

Recently, stem cell-based therapies have been proposed as an alternative for the treatment of many diseases. Stem cells (SCs) are well known for their capacity to preserve themselves, proliferate, and differentiate into multiple lineages. These characteristics allow stem cells to be a viable option for the treatment of diverse diseases. Traditional methodologies based on 2-dimensional culture techniques (T-flasks and Petri dishes) are simple and well standardized; however, they present disadvantages that limit the production of the cell yield required for regenerative medicine applications. Lately, microcarrier (MC)-based culture techniques have emerged as an attractive platform for expanding stem cells in suspension systems. Although the use of stem cell expansion on MCs has recently shown significant increase, their implementation for medical purposes is been hampered by bottlenecks in upstream and downstream processing. Therefore, there is an urgent need in the development of bioprocesses that simplify stem cell cultures under xeno-free conditions and detachment from MCs without diminishing their pluripotency and viability. A critical analysis of the factors that impact the up and downstream bioprocessing on MC-based stem cell cultures is presented in this review. This analysis aims to raise the awareness of the current drawbacks that limit MC-based stem cell bioprocessing in regenerative medicine and propose alternatives to overcome them.

Enzymatic Methods for Salivary Biomarkers Detection: Overview and Current Challenges.

Early detection is a key factor in patient fate. Currently, multiple biomolecules have been recognized as biomarkers. Nevertheless, their identification is only the starting line on the way to their implementation in disease diagnosis. Although blood is the biofluid par excellence for the quantification of biomarkers, its extraction is uncomfortable and painful for many patients. In this sense, there is a gap in which saliva emerges as a non-invasive and valuable source of information, as it contains many of the biomarkers found in blood. Recent technological advances have made it possible to detect and quantify biomarkers in saliva samples. However, there are opportunity areas in terms of cost and complexity, which could be solved using simpler methodologies such as those based on enzymes. Many reviews have focused on presenting the state-of-the-art in identifying biomarkers in saliva samples. However, just a few of them provide critical analysis of technical elements for biomarker quantification in enzymatic methods for large-scale clinical applications. Thus, this review proposes enzymatic assays as a cost-effective alternative to overcome the limitations of current methods for the quantification of biomarkers in saliva, highlighting the technical and operational considerations necessary for sampling, method development, optimization, and validation.

Application of affinity aqueous two-phase systems for the fractionation of CD133(+) stem cells from human umbilical cord blood.

In a further attempt to establish a novel stem cell primary recovery strategy, the use of aqueous two-phase systems (ATPS) complemented with the use of antibodies (known as immunoaffinity ATPS) is explored in this work. This type of liquid-liquid extraction systems exploits antigen-antibody affinity and represents a novel and selective approach for the purification of stem cells. The proposed bioengineering strategies include the implementation of traditional [polyethylene glycol (PEG), dextran (DEX) and ficoll] and novel (Ucon) immunoaffinity ATPS to prove the viability of cluster of differentiation 133 (CD133(+) ) stem cells from human umbilical cord blood. Furthermore, the addition of the antibody is implemented to identify conditions under which contaminants and stem cells of interest concentrate in opposite phases. The objective of this work is to establish the initial basis for the development of a novel and scalable purification bioprocess for the selective recovery of CD133(+) stem cells employing immunoaffinity ATPS. The reported methodology allows a partitioning of 62% CD133(+) stem cells to the top phase of the ficoll 400,000-DEX 70,000 immunoaffinity ATPS. In PEG 8,000-DEX 500,000 and Ucon-DEX 75,000 systems, no difference was observed when compared with the conventional ATPS (without antibody addition), as the CD133 antibody does not have preference for the desired clean top phase. In all experiments, cell viability was at least 98% after ATPS recovery. This research highlights the challenges that must be addressed to allow the potential establishment of a separation process using immunoaffinity ATPS for the recovery and purification of stem cells.

Aldehyde PEGylation of laccase from Trametes versicolor in route to increase its stability: effect on enzymatic activity.

Laccase is a multicopper oxidase that catalyzes the oxidation of phenolic compounds. Laccase can be used in bioremediation, beverage (wine, fruit juice, and beer) processing, ascorbic acid determination, sugar beet pectin gelation baking, and as a biosensor. Recently, the antiproliferative activity of laccase toward tumor cells has been reported. Because of the potential applications of this enzyme, the efforts for enhancing and stabilizing its activity have increased. Thus, the PEGylation of laccase can be an alternative. PEGylation is the covalent attachment of one or more molecules of methoxy poly(ethylene glycol) (mPEG) to a protein. Normally, during the PEGylation reaction, the activity is reduced but the stability increases; thus, it is important to minimize the loss of activity. In this work, the effects of molar ratio (1:4, 1:8, and 1:12), concentration of laccase (6 and 12 mg/ml), reaction time (4 and 17 h), molecular weight, and type of mPEG (20, 30, 40 kDa and 40 kDa-branched) were analyzed. The activity was measured using three substrates: ABTS, 2,6-dimethoxyphenol, and syringaldazine. The best conditions for laccase PEGylation were 12 mg/ml of laccase, molar ratio 1:4, and 4 h reaction time. Under these conditions, the enzyme was able to maintain nearly 100% of its enzymatic activity with ABTS. The PEGylation of laccase has not been extensively explored, so it is important to analyze the effects of this bioconjugation in route to produce a robust modified enzyme.

Aqueous two-phase systems strategies to establish novel bioprocesses for stem cells recovery.

During the past decade, stem cell transplantation has emerged as a novel therapeutic alternative for several diseases. Nevertheless, numerous challenges regarding the recovery and purification steps must be addressed to supply the number of cells required and in the degree of purity needed for clinical treatments. Currently, there is a wide range of methodologies available for stem cells isolation. Nevertheless, there is not a golden standard method that accomplishes all requirements. A desirable recovery method for stem cells has to guarantee high purity and should be sensitive, rapid, quantitative, scalable, non- or minimally invasive to preserve viability and differentiation capacity of the purified cells. In this context, aqueous two-phase systems (ATPS) represent a promising alternative to fulfill the mentioned requirements, promoting the use of stem cell-based therapies for incurable diseases. This practical review focuses on presenting the bases for the development of a novel and scalable bioprocess for the purification of stem cells, with a case scenario of CD133(+) cells. The bioengineering strategies include the application of immunoaffinity ATPS in its multiple variants, including antibody-polymer conjugation, antibody addition and antibody immobilization. Conclusions are drawn in the light of the potential generic implementation of these strategies as an initial step in the establishment of bioprocesses for the purification of stem cells.

High Altitude Carotid Body Tumors Growth During active Surveillance.

BACKGROUND: The gold standard for patients with carotid body tumors (CBT) is surgical resection; nevertheless, some patients are unfit for surgery or, for other reasons, could not be operated on. Active surveillance has been known to be a reasonable strategy for these cases. This study aimed to evaluate tumor growth in unoperated patients with CBTs. METHODS: A retrospective review of all unoperated patients with CBT from a single academic hospital diagnosed between 2014 and 2021 was performed. Results of nonparametric testing were presented using the median and ranges for Mann-Whitney-U or Kruskal-Wallis. Significance was defined as a 2-tailed P < .05. RESULTS: The cohort included a total of 31 patients, with a median age of 60 years (range: 37-80 years), of which 27 (87.1%) were females. The patients live at a median altitude of 2800 meters (range: 2756-2980 meters) above sea level. Twenty (64.5%) patients had Shamblin I tumors, eight (25.8%) patients had Shamblin II tumors, and three (9.7%) patients had Shamblin III tumors. Median CBT volume at diagnosis was 14.1 cm3 (range: .9 - 213.3 cm3). Median volume at diagnosis of symptomatic tumors was substantially larger than asymptomatic tumors, 49.2 cm3 vs 7.9 cm3, respectively (P = .03). Median growth of the tumors during a median 15-month follow-up (range: 3-43 months) was 3.3 cm3 (range: 0-199.9 cm3). Overall, 77% (n = 24) of the CBTs grew at least 1 cm3. CONCLUSION: Most patients in the present study had tumor growth by at least 1 cm3, with a median tumor growth of 3.3 cm.3 In the present study tumor growth was shown to be greater than other low altitude CBT active surveillance studies; therefore, surgical resection should be recommended in patients with CBT living at high altitudes.

Current trends in carotid body tumors: Comprehensive review.

BACKGROUND: Carotid body tumor (CBT) is a rare neoplasm that has been increasingly studied during the last decades; nevertheless, it continues to be a topic of controversy. This review aims to provide an update on the general features of CBT and particularly review different treatment strategies and primary outcomes. METHODS: Data for this literature review were identified by PubMed, Scopus, and Medline. 93 articles from the initial search were included, as well as 28 relevant studies utilizing the snowballing method; totaling 121 articles about CBT. RESULTS: Main features such as anatomy, embryology, genetics, clinical presentation, and diagnosis of CBT are presented, followed by evidence of different treatment strategies such as radiotherapy, preoperative embolization, vascular resection, and vascular reconstruction. Main complications are also discussed. CONCLUSION: This review summarizes the most critical aspects regarding CBT. Future studies should compare different treatments to attain the best surgical results with lower morbidity rates.

Current Challenges and Future Trends of Enzymatic Paper-Based Point-of-Care Testing for Diabetes Mellitus Type 2.

A point-of-care (POC) can be defined as an in vitro diagnostic test that can provide results within minutes. It has gained enormous attention as a promising tool for biomarkers detection and diagnosis, as well as for screening of chronic noncommunicable diseases such as diabetes mellitus. Diabetes mellitus type 2 is one of the metabolic disorders that has grown exponentially in recent years, becoming one of the greatest challenges to health systems. Early detection and accurate diagnosis of this disorder are essential to provide adequate treatments. However, efforts to reduce incidence should remain not only in these stages but in developing continuous monitoring strategies. Diabetes-monitoring tools must be accessible and affordable; thus, POC platforms are attractive, especially paper-based ones. Paper-based POCs are simple and portable, can use different matrixes, do not require highly trained staff, and are less expensive than other platforms. These advantages enhance the viability of its application in low-income countries and hard-to-reach zones. This review aims to present a critical summary of the main components required to create a sensitive and affordable enzymatic paper-based POC, as well as an oriented analysis to highlight the main limitations and challenges of current POC devices for diabetes type 2 monitoring and future research opportunities in the field.

Laccases in Food Industry: Bioprocessing, Potential Industrial and Biotechnological Applications.

Laccase is a multi-copper oxidase that catalyzes the oxidation of one electron of a wide range of phenolic compounds. The enzyme is considered eco-friendly because it requires molecular oxygen as co-substrate for the catalysis and it yields water as the sole by-product. Laccase is commonly produced by fungi but also by some bacteria, insects and plants. Due it is capable of using a wide variety of phenolic and non-phenolic substrates, laccase has potential applications in the food, pharmaceutical and environmental industries; in addition, it has been used since many years in the bleaching of paper pulp. Fungal laccases are mainly extracellular enzyme that can be recovered from the residual compost of industrial production of edible mushrooms as Agaricus bisporus and Pleurotus ostreatus. It has also been isolated from microorganisms present in wastewater. The great potential of laccase lies in its ability to oxidize lignin, one component of lignocellulosic materials, this feature can be widely exploited on the pretreatment for agro-food wastes valorization. Laccase is one of the enzymes that fits very well in the circular economy concept, this concept has more benefits over linear economy; based on "reduce-reuse-recycle" theory. Currently, biorefinery processes are booming due to the need to generate clean biofuels that do not come from oil. In that sense, laccase is capable of degrading lignocellulosic materials that serve as raw material in these processes, so the enzyme's potential is evident. This review will critically describe the production sources of laccase as by-product from food industry, bioprocessing of food industry by-products using laccase, and its application in food industry.

Lower Urinary Tract and Gastrointestinal Dysfunction Are Common in Early Parkinson's Disease.

PURPOSE: Autonomic dysfunction is a common nonmotor feature and early manifestation of Parkinsons disease (PD). Autonomic dysfunction in PD is associated with a worse prognosis. We sought to characterize autonomic dysfunction and identify associated factors in patients with early PD. METHODS: An observational, cross-sectional, descriptive, and analytical study was conducted to evaluate patients with early PD from the Parkinsons Progression Markers Initiative. We utilized the Scales for Outcomes in Parkinsons Disease-Autonomic dysfunction questionnaire to determine the prevalence and frequencies of autonomic symptomatology. The cohort was grouped into high and low dysautonomic scores. A regression model identified variables that independently explained dysautonomic scores in our early PD cohort. RESULTS: 414 PD patients had a mean age of 61.1 (SD 9.7) years at diagnosis and mean disease duration of 6.7 (SD 6.6) months. Among all patients, 43.7% (181/414) had high dysautonomic scores. Urinary and gastrointestinal symptoms were the most prevalent and frequently reported dysautonomic symptoms. Patients with fatigue (beta = 4.28, p < 0.001), probable rapid eye movement sleep behavior disorder (beta = 2.71, p < 0.001), excessive daytime sleepiness (beta = 1.88,p=0.039), impulsivity and compulsivity (beta = 2.42, p < 0.001), and increasing age (beta = 1.05, p < 0.001) were more likely to have high dysautonomic scores. CONCLUSION: Lower urinary tract and gastrointestinal symptoms are prevalent and frequent in early PD patients. Fatigue, sleep disorders, impulsivity and compulsivity, and age are predictors of autonomic dysfunction. Autonomic symptoms predominated in this group of early PD patients in the disease course and were associated with more severe disease.

Thermo-separating polymer-based aqueous two-phase systems for the recovery of PEGylated lysozyme species.

Fractionation of native, mono and di-PEGylated lysozyme was performed in 36 different polymer-polymer aqueous two-phase systems using UCON as a phase-forming component. After a discrete partition analysis, dextran 75 kDa-UCON, volume ratio 3, tie-line length 35% w/w; ficoll 70 kDa-UCON, volume ratio 1, tie-line length 45% w/w and a PEG 8 kDa-UCON volume ratio 3, tie-line length 65% w/w systems were selected for optimization via salt addition and to observe the behavior of the lysozyme species in mixtures. The dextran-UCON and the PEG-UCON systems with 75 mM NaCl showed effectiveness in separating 75% and 87% of mono-PEGylated lysozyme from the rest of the lysozyme species in the top and bottom phases, respectively. These results are an advancement in incorporating these extractions in different processes since the use of UCON simplifies the removal of the polymers, providing the opportunity of recycling it to the operation.

Partition behavior of CD133(+) stem cells from human umbilical cord blood in aqueous two-phase systems: In route to establish novel stem cell primary recovery strategies.

Aqueous two-phase systems (ATPS) represent a promising strategy for the recovery of CD133(+) stem cells. This particular type of stem cells has great potential for research and clinical applications. Traditional [polyethylene glycol (PEG), dextran (DEX), and ficoll] and novel (Ucon) polymer-polymer ATPS were exploited to study the partitioning behavior of CD133(+) stem cells and contaminants from human umbilical cord blood (HUCB). The aim of the study was to select conditions under which the product of interest and the contaminants concentrate in opposite phases. To accomplish this, three independent samples were tested: (1) enriched CD133(+) sample, (2) whole HUCB (contaminants), and (3) complex sample (CD133(+) stem cells and contaminants). The objective of this research was to evaluate the partition behavior of CD133(+) in ATPS in route to establish the basis for the development of a novel and scalable purification bioprocess. In conclusion, the partitioning behavior of CD133(+) stem cells and contaminants from complex samples was as follows: 59% of CD133(+) stem cells fractionated to the top phase when employing ficoll 400,000-DEX 70,000 or 100% to the bottom phase with Ucon-DEX 75,000 and PEG 8,000-DEX 500,000 ATPS. In average, 35% of the contaminants partitioned to the top phase of the ficoll 400,000-DEX 70,000 ATPS, 99% to the dextran rich phase of the Ucon-DEX 75,000 systems and 97% to the bottom phase of the PEG 8,000-DEX 500,000. Cell viability was at least 98% after ATPS recovery.

PEGylation, detection and chromatographic purification of site-specific PEGylated CD133-Biotin antibody in route to stem cell separation.

Recovery and purification of stem cells are determining steps in order to obtain the purity and viability required for transplantation. In this context, immunochemical techniques have been widely preferred due to their high selectivity. CD133, a glycoprotein expressed by stem cells, is a well-used marker for isolation of neural stem cells. Transplantation of neural stem cells into patients can promote neural growth and improve neuronal functions. In this study, a new method for site-specific PEGylation of CD133-Biotin antibody is performed through streptavidin-biotin conjugation. Purification was carried out by ion-exchange chromatography. The characterization of the single PEGylated CD133-Biotin antibody was confirmed using electrophoresis with silver staining and I(2)-BaCl(2) for PEG detection. Moreover, online PEG quantification directly after the chromatographic step was conducted (in each fraction) to detect exact elution times of PEG. In conclusion, the novel CD133-Biotin antibody PEGylation strategy conducted in this study could be used as a process step in route to neural stem cell recovery and purification via the modification of existing techniques such as aqueous two phase systems, PEGylated affinity columns or fluidized chromatography.