[Endoscopic prevention of bleeding during resection of mucous membrane neoplasms of hollow organs of gastrointestinal tract]

OBJECTIVE

To optimize endoscopic prevention of bleeding during resection of mucous membrane neoplasms of hollow organs of gastrointestinal tract and minimize the risk of intra- and postoperative complications.

MATERIAL AND METHODS. A S

Ystematic review and meta-analysis were made in accordance with the PRISMA recommendations. Statistical analysis was performed in Cohrane Review Manager ver. 5.4.

RESULTS. THERE ARE 3

Methods of endoscopic prevention of bleeding during polypectomy, i.e. 0.01% adrenaline injection, endoscopic clip placement and endoscopic polyp band ligation. Endoscopic polyp band ligation is characterized by minimum complication rate.

CONCLUSION

Endoscopic polyp band ligation is preferable due to minimum complication rate. If ligation is impossible, prophylactic clip placement may be performed. Adrenaline injection is the least effective method and may be used only if two above-mentioned methods are ineffective.

[Prevention of bleeding in polypectomy]

OBJECTIVE

To improve early treatment outcomes in patients with gastrointestinal polyps using a new device designed for prevention of bleeding during endoscopic minimally invasive polypectomy.

MATERIAL AND METHODS

A prospective trial included 35 patients with 36 colonic polyps (stalk diameter >5 mm). Polyp ligation procedure was performed using a novel device providing delivery and tightening the knot before polypectomy.

RESULTS

All polyps were successfully removed without any technical difficulties and exposed to histological examination. Mean age of patients was 64 years (52-81), mean dimension of polyps - 15.6 mm (10-40), mean thickness of stalk - 8 mm (5-12). There were no intraoperative and early postoperative complications. All patients were discharged after 2 postoperative days.

CONCLUSION

The proposed method for prevention of bleeding during polypectomy is simple, effective and safe for clinical practice.

Abstract 5270: Developing a predictive model for pancreatic neuroendocrine tumor metastatic potential: A multi-institutional analysis

Pancreatic neuroendocrine tumors (PNETs) are rare neoplasms that arise from cells in the islets of Langerhans, with surgical resection presently recommended for tumors > 2cm. While many PNETs have the propensity to be indolent, some small tumors display aggressive features with early metastatic potential. We used machine learning to develop a predictive model of metastatic potential dependent upon the transcriptomic signature of primary PNET tissue. To build this model, RNA sequencing data was obtained from the primary tissue of 96 surgically-resected PNETs from various institutions. Two cohorts were generated with equally balanced metastatic PNET composition (15 (32.6%) vs. 13 (26.5%), p=0.52). A differential gene expression analysis identified 20 concordantly differentially expressed genes associated with metastatic status between the two cohorts. Unsupervised surrogate variable analysis estimated and adjusted for significant sources of variation not related to metastatic potential and mitigated unwanted noise and batch effects. A gene set enrichment analysis identified an additional 29 genes that most frequently contributed to the enriched biologic pathways extrapolated from the sequencing data. Log transformed, batch corrected TPM values for these 49 genes were combined with an additional 10 clinically-relevant genes, including ARX and PDX1, that are known to contribute to PNET signatures or oncogenesis. The datasets were subsequently randomized in a 1:1 ratio and informative features with respect to metastatic status were identified utilizing a Boruta algorithm, with a priori exclusion of highly-correlative genes and those that displayed near zero variance. Nine genes, including AURKA, ARX, CDCA8, CPB2, MYT1L, NDC80, PAPPA2, SFMBT1 and ZPLD1, were identified as sufficient to classify the localized or metastatic outcome. Distributed random forests (DRF), generalized linear models (GLM), gradient boosting machines (GBM) and extreme gradient boosting (XGBoost) models were trained utilizing these 9 genes. Training ROC ranged from 0.92 for DRF to 1 for XGboost. When applied to 47 independent validation samples, the testing sensitivity ranged from 75% for DRF to 94% for GBM; specificity ranged from 84% for DRF to 94% to XGboost and GLM; positive predictive value ranged from 72% for DRF to 86% for GLM; negative predictive value ranged from 88% for GLM to 97% to GBM. The degree of predictive agreement between models ranged from 64% to 91%. Taken together, we have developed a highly sensitive predictive model of the metastatic PNET phenotype that is based on expression of nine genes. Its application as a guide for management should be studied prospectively in patients with newly diagnosed PNETs.

Citation Format: Jacques A. Greenberg, Nikolay A. Ivanov, Yajas Shah, Scott Kulm, Jelani Williams, Catherine G. Tran, Theresa Scognamiglio, Yeon Joo Lee, Caitlin E. Egan, Irene M. Min, Rasa Zarnegar, James Howe, Xavier Keutgen, Thomas J. Fahey, Olivier Elemento, Brendan M. Finnerty. Developing a predictive model for pancreatic neuroendocrine tumor metastatic potential: A multi-institutional analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5270.

Theoretical Investigation of Carbon Dioxide Adsorption on Li+-Decorated Nanoflakes

Recently, the capture of carbon dioxide, the primary greenhouse gas, has attracted particular interest from researchers worldwide. In the present work, several theoretical methods have been used to study adsorption of CO2 molecules on Li+-decorated coronene (Li+@coronene). It has been established that Li+ can be strongly anchored on coronene, and then a physical adsorption of CO2 will occur in the vicinity of this cation. Moreover, such a decoration has substantially improved interaction energy (Eint) between CO2 molecules and the adsorbent. One to twelve CO2 molecules per one Li+ have been considered, and their Eint values are in the range from -5.55 to -16.87 kcal/mol. Symmetry-adapted perturbation theory (SAPT0) calculations have shown that, depending on the quantity of adsorbed CO2 molecules, different energy components act as the main reason for attraction. AIMD simulations allow estimating gravimetric densities (GD, wt.%) at various temperatures, and the maximal GDs have been calculated to be 9.3, 6.0, and 4.9% at T = 77, 300, and 400 K, respectively. Besides this, AIMD calculations validate stability of Li+@coronene complexes during simulation time at the maximum CO2 loading. Bader's atoms-in-molecules (QTAIM) and independent gradient model (IGM) techniques have been implemented to unveil the features of interactions between CO2 and Li+@coronene. These methods have proved that there exists a non-covalent bonding between the cation center and CO2. We suppose that findings, derived in this theoretical work, may also benefit the design of novel nanosystems for gas storage and delivery.

Association of the Affordable Care Act with access to highest-volume centers for patients with thyroid cancer

BACKGROUND

Disparities exist in access to high-volume surgeons, who have better outcomes after thyroidectomy. The association of the Affordable Care Act's Medicaid expansion with access to high-volume thyroid cancer surgery centers remains unclear.

METHODS

The National Cancer Database was queried for all adult thyroid cancer patients diagnosed from 2010 to 2016. Hospital quartiles (Q1-4) defined by operative volume were generated. Clinicodemographics and adjusted odds ratios for treatment per quartile were analyzed by insurance status. An adjusted difference-in-differences analysis examined the association between implementation of the Affordable Care Act and changes in payer mix by hospital quartile.

RESULTS

In total, 241,448 patients were included. Medicaid patients were most commonly treated at Q3-Q4 hospitals (Q3 odds ratios 1.05, P = .020, Q4 1.11, P < .001), whereas uninsured patients were most often treated at Q2-Q4 hospitals (Q2 odds ratios 2.82, Q3 2.34, Q4 2.07, P < .001). After expansion, Medicaid patients had lower odds of surgery at Q3-Q4 compared with Q1 hospitals (odds ratios Q3 0.82, P < .001 Q4 0.85, P = .002) in expansion states, but higher odds of treatment at Q3-Q4 hospitals in nonexpansion states (odds ratios Q3 2.23, Q4 1.86, P < .001). Affordable Care Act implementation was associated with increased proportions of Medicaid patients within each quartile in expansion compared with nonexpansion states (Q1 adjusted difference-in-differences 5.36%, Q2 5.29%, Q3 3.68%, Q4 3.26%, P < .001), and a decrease in uninsured patients treated at Q4 hospitals (adjusted difference-in-differences -1.06%, P = .001).

CONCLUSIONS

Medicaid expansion was associated with an increased proportion of Medicaid patients undergoing thyroidectomy for thyroid cancer in all quartiles, with increased Medicaid access to high-volume centers in expansion compared with nonexpansion states.

Shotgun transcriptome, spatial omics, and isothermal profiling of SARS-CoV-2 infection reveals unique host responses, viral diversification, and drug interactions

In less than nine months, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) killed over a million people, including >25,000 in New York City (NYC) alone. The COVID-19 pandemic caused by SARS-CoV-2 highlights clinical needs to detect infection, track strain evolution, and identify biomarkers of disease course. To address these challenges, we designed a fast (30-minute) colorimetric test (LAMP) for SARS-CoV-2 infection from naso/oropharyngeal swabs and a large-scale shotgun metatranscriptomics platform (total-RNA-seq) for host, viral, and microbial profiling. We applied these methods to clinical specimens gathered from 669 patients in New York City during the first two months of the outbreak, yielding a broad molecular portrait of the emerging COVID-19 disease. We find significant enrichment of a NYC-distinctive clade of the virus (20C), as well as host responses in interferon, ACE, hematological, and olfaction pathways. In addition, we use 50,821 patient records to find that renin-angiotensin-aldosterone system inhibitors have a protective effect for severe COVID-19 outcomes, unlike similar drugs. Finally, spatial transcriptomic data from COVID-19 patient autopsy tissues reveal distinct ACE2 expression loci, with macrophage and neutrophil infiltration in the lungs. These findings can inform public health and may help develop and drive SARS-CoV-2 diagnostic, prevention, and treatment strategies.

Shotgun Transcriptome and Isothermal Profiling of SARS-CoV-2 Infection Reveals Unique Host Responses, Viral Diversification, and Drug Interactions

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused thousands of deaths worldwide, including >18,000 in New York City (NYC) alone. The sudden emergence of this pandemic has highlighted a pressing clinical need for rapid, scalable diagnostics that can detect infection, interrogate strain evolution, and identify novel patient biomarkers. To address these challenges, we designed a fast (30-minute) colorimetric test (LAMP) for SARS-CoV-2 infection from naso/oropharyngeal swabs, plus a large-scale shotgun metatranscriptomics platform (total-RNA-seq) for host, bacterial, and viral profiling. We applied both technologies across 857 SARS-CoV-2 clinical specimens and 86 NYC subway samples, providing a broad molecular portrait of the COVID-19 NYC outbreak. Our results define new features of SARS-CoV-2 evolution, nominate a novel, NYC-enriched viral subclade, reveal specific host responses in interferon, ACE, hematological, and olfaction pathways, and examine risks associated with use of ACE inhibitors and angiotensin receptor blockers. Together, these findings have immediate applications to SARS-CoV-2 diagnostics, public health, and new therapeutic targets.

Divergent neuronal DNA methylation patterns across human cortical development reveal critical periods and a unique role of CpH methylation

Background

DNA methylation (DNAm) is a critical regulator of both development and cellular identity and shows unique patterns in neurons. To better characterize maturational changes in DNAm patterns in these cells, we profile the DNAm landscape at single-base resolution across the first two decades of human neocortical development in NeuN+ neurons using whole-genome bisulfite sequencing and compare them to non-neurons (primarily glia) and prenatal homogenate cortex.

Results

We show that DNAm changes more dramatically during the first 5 years of postnatal life than during the entire remaining period. We further refine global patterns of increasingly divergent neuronal CpG and CpH methylation (mCpG and mCpH) into six developmental trajectories and find that in contrast to genome-wide patterns, neighboring mCpG and mCpH levels within these regions are highly correlated. We integrate paired RNA-seq data and identify putative regulation of hundreds of transcripts and their splicing events exclusively by mCpH levels, independently from mCpG levels, across this period. We finally explore the relationship between DNAm patterns and development of brain-related phenotypes and find enriched heritability for many phenotypes within identified DNAm features.

Conclusions

By profiling DNAm changes in NeuN-sorted neurons over the span of human cortical development, we identify novel, dynamic regions of DNAm that would be masked in homogenate DNAm data; expand on the relationship between CpG methylation, CpH methylation, and gene expression; and find enrichment particularly for neuropsychiatric diseases in genomic regions with cell type-specific, developmentally dynamic DNAm patterns.

Electronic supplementary material

The online version of this article (10.1186/s13059-019-1805-1) contains supplementary material, which is available to authorized users.

Integrate imaging approach for minimally invasive and robotic procedures

Over the past two decades, robotic and minimally invasive cardiac surgery has been continuously refined and is currently an alternative to traditional open-heart surgery for some patients. The parallel evolution of imaging modalities has made robotic surgery safer and more efficient. Here, we review the pre- and post-operative use of computed tomography (CT) in minimally invasive and robotic cardiac procedures.

Nanostructure changes in the intervertebral discs after experimental laser irradiation

Laser-induced changes in the intervertebral discs were studied by the method of atomic force microscopy. Alteration of the proximal caudal intervertebral discs was modeled in rats: puncture and exposure to diode laser (2, 3, or 5 W) in constant or pulse regimens or only puncture (control). Nanostructure of disc surface was estimated by surface skewness, root mean square and average roughness, and coefficient of kurtosis. Maximum positive effect and signs of regenerative changes in the surface microstructure of the intervertebral discs were found after exposure to laser (2-3 W) in constant or pulse regimens.

[Analysis of efficacy of complex treatment of patients with differentiated forms of the thyroid gland cancer using distant radiation therapy]

Retrospective analysis of efficacy of complex treatment, including surgical intervention, radioiodine therapy (RITH), suppressive hormonotherapy of differentiated forms of the thyroid gland cancer (DFTHGC) was done in 281 patients with positive effect of postoperative distant radiation therapy (PDRTH) application as a component of the treatment. Positive effect of therapy was estimated basing on the dynamic scintigraphy data with 131I and determination of thyroglobulin level in blood serum. The PDRTH conduction does not improve prognosis of the disease, does not lower the tumor metastasizing frequency to regional lymph nodes and remote organs and does not replace RITH. To achieve positive result in 12.8% of patients with PDRTH more than two courses of RITH were performed, enhancing so the total radiation dosage on the organism. To provide protracted nonrecurrent survival of patients with DFTHGC the radical approach is necessary, envisaging performance of thyroidectomy, the timely conduction of RITH with subsequent suppressive therapy using L-thyroxin.

[Treatment and monitoring of patients with differentiated cancer of thyroid gland]

There were examined 200 patients aged from 19 to 77 years with differentiated cancer of the thyroid gland (TG). The combined treatment, which included performance of operation, radioiodine therapy and hormonotherapy, was conducted to all the patients. Total and maximum subtotal TG resection was performed in 90% patients, nonradical operation--in 10%, 23% patients were reoperated. Postoperative monitoring according to chart was done with application of dynamic scintigraphy and determination of the thyroglobuline level in the blood serum. The TG residual tissue (RT) was revealed in 61% patients and in 39%--the cancer metastases in the lymphatic nodes. RT of TG was eliminated in 86.8% patients after the first radioiodine therapy course conduction in middle remedial activity (2.79 +/- 0.11) GBq, the metastases devitalization--in 67.9% in middle remedial activity (4.07 +/- 0.12) GBq.

[Comparative analysis of antibiotic sensitivity of Streptococcus pneumoniae strains isolated from patients and carriers]

The data on antibiotic sensitivity of 38 strains of S. pneumoniae isolated from children and 46 strains isolated from carriers are presented. The isolates from the carriers had significantly higher sensitivity to benzylpenicillin, ampicillin, methicillin, oxacillin, cefazolin, erythromycin, oleandomycin and lincomycin. Resistance to gentamicin was more frequent in the strains isolated from the carriers. Among the strains of S. pneumoniae isolated from the patients and carriers representatives of serovar K19 were more frequent. There were no statistically reliable difference in them by sensitivity to benzylpenicillin, ampicillin, cefazolin, lincomycin and rifampicin. Still, the isolates from the carriers were much more sensitive to methicillin, oxacillin, oleandomycin and erythromycin.

[Characteristics of staphylococci isolated from newborn infants]

The microflora of the skin and the nasal mucosa was studied in 14 healthy newborns, 3 newborns with purulent infections and a nurse working in a neonatal ward. To make this study, washings were obtained with the use of 0.1% Triton X-100 solution. The determination of the number of microorganisms, the percentage of staphylococci, the percentage of lecithinase-positive staphylococci and the number of colonies with antagonistic properties revealed that these characteristics differed according to the state of health of the newborns and the time elapsed after their birth, and that changes in the number of antagonistically active bacteria occurred in parallel with changes in the total number of bacteria. Among S. aureus strains isolated from the subjects covered by the survey strains belonging to phagovar 80, as well as untyped strains, and among S. epidermidis strains those belonging to biovars I and II occurred most frequently. Strains belonging to the same biovar or phagovar differed in their plasmid markers.

[Production of penicillinase by staphylococcal strains of different origins]

A total of 319 strains of S. aureus and 729 strains of S. epidermidis belonging to different biovars isolated from the skin and nasal mucosa of 349 persons representing 8 independent groups were tested. On the whole production of penicillinase was more often observed in the strains of S. aureus than in the strains of S. epidermidis. Within the first species this property was more often detected in the strains of biovar I as compared to the other biovars. However, the frequency of the penicillinase-producing strains within S. aureus and the biovars of S. epidermidis markedly varied.

[Transformation of Bacillus subtilis by crude lysates containing staphylococcal plasmid DNA]

Crude lysates from staphylococcal strains, containing DNA, were capable of transforming Bacillus subtilis at a rate of 1.68 X 10(-10) - 20.6 X 10(-10) depending on the marker according to which the transformers were selected. In a new host, plasmids showed the same behavior pattern as in the staphylococcus but their spontaneous loss was in all the cases recorded significantly more often.

[Growth indices of Bacillus subtilis clones transformed by staphylococcal plasmid DNA]

B. subtilis strain 168 was transformed by means of staphylococcal plasmids responsible for resistance to penicillins and levomycetin, as well as for resistance to cadmium ions and for bacteriocinogenicity linked with resistance to cadmium ions. In the new host these plasmids affected the duration of the lag phase and the time of generation. The production of staphylococcal bacteriocin in B. subtilis was accompanied by the lysis of the cells.

[Transfer of the bacteriocinogenicity plasmid in mixed staphylococcal populations]

The capacity of the bactericinogenicity plasmid in S. epidermidis strain NI 17 to be transferred to nonbactericinogenic staphylococcal strains in mixed populations was studied. 3 out of 22 studied S. aureus strains and 3 out of 24 studied S. epidermidis strains were found to be capable of receiving the plasmid. No recombinants could be obtained with these recipients, which was seemingly due to the presence of the restriction and modification systems in plasmid DNA. The experiments, where the variants of S. epidermidis strain NI 17, having no plasmid, but resistant to antibiotics as the result of mutation, were used as recipients, revealed that the initial strain contained at least 2 plasmids, one of them controlling resistance to cadmium ions and the other responsible for the synthesis of bactericin.

[Transfer of plasmid bacteriocinogenicity during the growth process of a population of staphylococci]

Staphylococcus epidermidis strain No. 17 containing the bacteriocinogenicity plasmid and incapable of the spontaneous loss of this plasmid was studied. When the contact between the dividing cells was broken by shaking, the cells without the plasmid were shown to appear in the population starting from the 30th minute of cultivation. In all cases the loss of the plasmid due to the action of acridine orange at 37 degrees C and 44 degrees C, as well as in cultivation at 44 degrees C, occurred more frequently when the growing population was shaken than in the absence of shaking. This suggests the possibility of transferring the plasmid controlling bacteriocinogenicity in the process of the growth of staphylococcal population.

[Genetic structure of Staphylococcus epidermidis strain No. 17 possessing penicillinase and bacteriocinogenic activity]

The studies on the genetic structure of Staphylococcus epidermidis, strain 17 showed that this strain possessed a factor of bactericinogenicity of the one type, which was an extrachromosomal element not bound with penicillinase activity. The loss of the bacteriocinogenicity factor spontaneously or under the effect of acridine orange at a temperature of 37 degrees C was not observed. Passages of the strain at a temperature of 44 degrees C for 5 days and acridine orange proved to be the most effective eliminating factors. The loss of the bacteriocinogenicity plasmid did not result in changing any biochemical properties of the strain but was accompanied by a loss of the immunity to bacteriocin of the initial strain. The study of the growth regularities of the initial strain and its variant deprived of the bacteriocinogenicity plasmid showed that multiplication of the cells in the presence of the plasmid practically started without the latent period.

[Mechanism of staphylococcin formation]

The author studied the optic density and the viable cell count in 2 strains of bacteriocinogenic staphylococci and their variants in which the bacteriocinogenicity factor was eliminated. Latent phase was prolonged in strains devoid of bacteriocinogenic factor; it was practically absent in bacteriocinogenic cultures. Bacteriocin production began on the 60th minute and this was accompanied by the death of cells and their lysosomes. With further culture growth bacteriocin formed in jerks and this was accompanied by the death of cells and their lysosomes.

[Genetic nature of the bacteriocinogenicity factor of Staphylococcus epidermidis strain No. 259]

Genetic nature of the bacteriogenicity factor of the Staphylococcus epidermidis No. 259 strain was studied by acting upon the strain with ultraviolet irradiation, acridine orange at a temperature of 37 and 44 degrees C, and cultivation of the strain at a temperature of 44 degrees C for 24 and 96 hours. The most effective elimination of the bacteriocinogenicity factor was reached with the action of acridine orange at 44 degrees C and the strain passage at 44 degrees C for 96 hours. A study of 212 subcultures which lost the bacteriocinogenicity factor under the effect of various factors demonstrated that they failed to differ by properties from the initial strain and retained the bacteriocin resistance of the initial strain. A conclusion was drawn that the bacteriocinogenicity factor was an extrachomosomic agent, and was not associated with any other strain properties.