Nerve monitoring in endocrine surgery: Practice patterns differ among surgeons for parathyroidectomy and thyroidectomy

BACKGROUND

It is unknown whether intraoperative nerve monitoring is associated with reduced vocal cord dysfunction after parathyroidectomy. We aimed to investigate intraoperative nerve monitoring use among Collaborative Endocrine Surgery Quality Improvement Program surgeons and factors associated with vocal cord dysfunction after parathyroidectomy.

METHODS

Patients who underwent parathyroidectomy included in the Collaborative Endocrine Surgery Quality Improvement Program (2014-2022) were identified. The annual percent change in parathyroidectomies performed with intraoperative nerve monitoring was calculated using joinpoint regression. Multivariable logistic regression was used to compare outcomes between patients undergoing parathyroidectomy with/without intraoperative nerve monitoring. To compare surgeon-specific trends, Collaborative Endocrine Surgery Quality Improvement Program thyroidectomy and parathyroidectomy datasets (2014-2021) were combined. Parathyroidectomies performed by surgeons who used intraoperative nerve monitoring consistently in thyroidectomy were identified. Factors associated with intraoperative nerve monitoring were examined using multivariable logistic regression.

RESULTS

A total of 9,813 patients underwent parathyroidectomy. Intraoperative nerve monitoring was used in 49% of cases (n = 4,818). There was an increase in parathyroidectomies with intraoperative nerve monitoring from 2014 to 2018 (annual percent change 22.2, P = .01), followed by a plateau (2018-2022 annual percent change -0.66, P = .85). Few patients (0.44%, n = 43) developed vocal cord dysfunction. Vocal cord dysfunction was not associated with intraoperative nerve monitoring (adjusted odds ratio 0.92, P = .75). Whereas 41% (n = 56/138) of surgeons used intraoperative nerve monitoring routinely in parathyroidectomy, 65% (n = 90/138) used it routinely in thyroidectomy. Among surgeons who used intraoperative nerve monitoring routinely in thyroidectomy, only 57% used it routinely in parathyroidectomy; factors associated with intraoperative nerve monitoring during parathyroidectomy included reoperation (adjusted odds ratio 2.51, P < .01), secondary/tertiary hyperparathyroidism (adjusted odds ratio 1.42, P = .02), multiglandular disease (adjusted odds ratio 1.76, P < .001), and non-localized disease (adjusted odds ratio 1.65, P < .001).

CONCLUSION

Endocrine surgeons use intraoperative nerve monitoring selectively. Surgeons who routinely use intraoperative nerve monitoring during thyroidectomy are more likely to use it during parathyroidectomy. Future studies should determine who may benefit most from intraoperative nerve monitoring in parathyroidectomy.

Enhanced recovery after surgery (ERAS) in colorectal surgery: implementation is still beneficial despite modern surgical and anesthetic care

PURPOSE

Enhanced recovery after surgery (ERAS) protocols have shown beneficial outcomes in the last 20 years. Nevertheless, simultaneously implemented technical improvements such as minimally invasive access or modified anesthesia care may play a crucial role in optimizing patient outcome. The aim of the study was to investigate the effect of ERAS implementation in a highly specialized colorectal center.

METHODS

This is a propensity score matched single-center study comparing the short-term outcomes of patients undergoing elective colorectal surgery in a society-indepedent ERAS program from January 2021 to August 2022 to standard perioperative care from January 2019 to December 2020.

RESULTS

Four hundred fifty-six patients were included in the propensity score matched analysis with 228 patients per group (ERAS vs. standard care). Minimally invasive access was used in 80.2% vs. 77.6% (p = 0.88), and there were 16.6% vs. 18.8% (p = 0.92) rectal procedures in the ERAS and standard care group, respectively. Major complications occurred in 10.1% vs. 11.4% (p = 0.65) and anastomotic leakage demanding operative revision in 2.2% vs. 2.6% (p = 0.68) in the ERAS and standard care group, respectively. ERAS lead to a lower number of non-surgical complications compared to standard care (57 vs. 79; p = 0.02). Mean length of stay (LOS) and mean costs per case were lower in ERAS compared to standard care (9.2 ± 5.6 days vs. 12.7 ± 7.4 days, p < 0.01; costs 33,727 ± 15,883 USD vs. 40,309 ± 29,738 USD, p < 0.01).

CONCLUSION

The implementation of an ERAS protocol may lead to a reduction of LOS, costs, and a lower number of non-surgical complications even in a highly specialized colorectal unit using modern surgical and anesthetic care. ( ClinialTrials.gov number NCT05773248).

Interlaboratory comparison using inactivated SARS-CoV-2 variants as a feasible tool for quality control in COVID-19 wastewater monitoring

Wastewater-based SARS-CoV-2 epidemiology (WBE) has proven as an excellent tool to monitor pandemic dynamics supporting individual testing strategies. WBE can also be used as an early warning system for monitoring the emergence of novel pathogens or viral variants. However, for a timely transmission of results, sophisticated sample logistics and analytics performed in decentralized laboratories close to the sampling sites are required. Since multiple decentralized laboratories commonly use custom in-house workflows for sample purification and PCR-analysis, comparative quality control of the analytical procedures is essential to report reliable and comparable results. In this study, we performed an interlaboratory comparison at laboratories specialized for PCR and high-throughput-sequencing (HTS)-based WBE analysis. Frozen reserve samples from low COVID-19 incidence periods were spiked with different inactivated authentic SARS-CoV-2 variants in graduated concentrations and ratios. Samples were sent to the participating laboratories for analysis using laboratory specific methods and the reported viral genome copy numbers and the detection of viral variants were compared with the expected values. All PCR-laboratories reported SARS-CoV-2 genome copy equivalents (GCE) for all spiked samples with a mean intra- and inter-laboratory variability of 19 % and 104 %, respectively, largely reproducing the spike-in scheme. PCR-based genotyping was, in dependence of the underlying PCR-assay performance, able to predict the relative amount of variant specific substitutions even in samples with low spike-in amount. The identification of variants by HTS, however, required >100 copies/ml wastewater and had limited predictive value when analyzing at a genome coverage below 60 %. This interlaboratory test demonstrates that despite highly heterogeneous isolation and analysis procedures, overall SARS-CoV-2 GCE and mutations were determined accurately. Hence, decentralized SARS-CoV-2 wastewater monitoring is feasible to generate comparable analysis results. However, since not all assays detected the correct variant, prior evaluation of PCR and sequencing workflows as well as sustained quality control such as interlaboratory comparisons are mandatory for correct variant detection.

High density of CXCL12-positive immune cell infiltration predicts chemosensitivity and recurrence-free survival in ovarian carcinoma

BACKGROUND

Ovarian carcinoma is the most lethal gynecologic malignancy because of its late diagnosis, extremely high recurrence rate, and limited curative treatment options. In clinical practice, high-grade serous carcinoma (HGSC) predominates due to its frequency, high aggressiveness, and rapid development of drug resistance. Recent evidence suggests that CXCL12 is an important immunological factor in ovarian cancer progression. Therefore, we investigated the predictive and prognostic significance of the expression of this chemokine in tumor and immune cells in patients with HGSC.

METHODS

We studied a cohort of 47 primary high-grade serous ovarian carcinomas and their associated recurrences. A tissue microarray was constructed to evaluate the CXCL12 immunostained tumor tissue. CXCL12 expression was evaluated and statistically analyzed to correlate clinicopathologic data, overall survival, and recurrence-free survival.

RESULTS

A high proportion of CXCL12 + positive immune cells in primary ovarian serous carcinoma correlated significantly with chemosensitivity (p = 0.005), overall survival (p = 0.021), and longer recurrence-free survival (p = 0.038). In recurrent disease, high expression of CXCL12 was also correlated with better overall survival (p = 0.040). Univariate and multivariate analysis revealed that high CXCL12 + tumor-infiltrating immune cells (TICs) (HR 0.99, p = 0.042, HR 0.99, p = 0.023, respectively) and combined CXCL12 + /CD66b + infiltration (HR 0.15, p = 0.001, HR 0.13, p = 0.001, respectively) are independent favorable predictive markers for recurrence-free survival.

CONCLUSION

A high density of CXCL12 + TICs predicts a good response to chemotherapy, leading to a better overall survival and a longer recurrence-free interval. Moreover, with concomitant high CXCL12/CD66b TIC density, it is an independent favorable predictor of recurrence-free survival in patients with ovarian carcinoma.

Low serum iPTH at the end of surgery is the earliest predictor of postoperative hypocalcemia after total thyroidectomy

BACKGROUND

The most frequent complication of total thyroidectomy remains hypocalcemia due to low postoperative levels of serum intact parathyroid hormone (iPTH). The purpose of this study was to investigate the role of decreased iPTH at the end of surgery in predicting hypocalcemia. In addition, we examined the percentage decrease of iPTH as potential indicator of hypocalcemia.

METHODS

We retrospectively collected the data of patients who underwent total thyroidectomy for benign and malignant diseases at our institution between 2010 and 2022. The iPTH level was measured before and at the end of surgery, and serum calcium levels on the first postoperative day. Demographic, clinical, and biochemical characteristics of patients with low iPTH were compared with patients with normal iPTH levels using ANOVA for continuous variables and χ2-tests for categorical variables. Multivariable logistic regression analysis evaluated the association of iPTH at the end of surgery and the relative reduction of iPTH with postoperative hypocalcemia.

RESULTS

The mean age of the 607 patients in this study was 55.6 years, and the female-to-male ratio was 5:1. Goiter was the most common indication for surgery (N = 382, 62.9%), followed by Graves' disease (N = 135, 22.2%). The mean preoperative iPTH was 49.0 pg/ml, while the mean postoperative iPTH was 29.3 pg/ml. A total of 197 patients (32.5%) had an iPTH level below normal, 77 patients (39%), had iPTH levels of 10-15.0 pg/ml and 120 patients (61%) of < 10.0 pg/ml at the end of surgery. Among all patients, 124 (20.4%) developed hypocalcemia on the first postoperative day. The mean percentage of decrease of iPTH was highest among patients with iPTH < 10 pg/ml (76.9%, p < 0.01); this group of patients had also the highest rate of postoperative hypocalcemia on day one (45.0% vs. 26.0% vs 12.2%, p < 0.01).

CONCLUSIONS

Measurement of iPTH at the end of total thyroidectomy predicts patients who are at risk for postoperative hypocalcemia. The combination of low serum iPTH with a decrease in iPTH level of ≥ 50% may improve prediction of hypocalcemia compared to iPTH levels alone allowing for early calcium substitution in these patients at high risk of developing postoperative hypocalcemia.

The VBNC state: a fundamental survival strategy of Acinetobacter baumannii

IMPORTANCE

Currently, the viable but non-culturable (VBNC) state is an underappreciated niche for pathogenic bacteria which provides a continuous source for recurrent infections and transmission. We propose the VBNC state to be a global persistence mechanism used by various A. baumannii strains to cope with many stresses it is confronted with in the clinical environment and in the host. This requires a novel strategy to detect viable cells of this pathogen that is not only based on plating assays.

Routine use of intraoperative nerve monitoring is associated with a reduced risk of vocal cord dysfunction after thyroid cancer surgery

BACKGROUND

The aim of this study was to investigate the associations between individual surgeon's intraoperative nerve monitoring (IONM) practice and factors associated with vocal cord (VC) dysfunction in patients with thyroid cancer undergoing thyroidectomy.

METHODS

Using Collaborative Endocrine Surgery Quality Improvement Program (CESQIP) 2014-21 data, multivariable logistic regression analyses investigated variables associated with short- and long-term VC-dysfunction, associations of routine use of IONM with postoperative outcomes, and patient characteristics associated with IONM use.

RESULTS

Among 5,446 patients (76.7% female, mean age 49 years), 68.5% had surgery by surgeons using IONM in ≥ 90% of cases (63% of surgeons, n = 73). Post-operative VC-dysfunction was diagnosed by laryngoscopy in 3.0% of patients in the short-term and 2.7% in the long-term. When surgeons routinely used IONM, the incidence of VC-dysfunction was 2.4% in the short-term and 2.2% in the long-term, compared to 4.4% and 3.7%, respectively, when surgeons did not routinely use IONM (p < 0.01). After adjustment, routine use of IONM was independently associated with reduced risk of short- (OR 0.48, p < 0.01) and long-term (OR 0.52, p < 0.01) VC-dysfunction, a lower risk of postoperative hypoparathyroidism in the short- (OR 0.67, p < 0.01) and long-term (OR 0.54, p < 0.01), and higher likelihood of same-day discharge (OR 2.03, p < 0.01). Extrathyroidal tumor extension and N1-stage were factors associated with postoperative VC-dysfunction in the short- (OR 3.12, p < 0.01; OR 1.92, p = 0.01, respectively) and long-term (OR 3.11, p < 0.01; OR 2.32, p < 0.01, respectively).

CONCLUSION

Routine use of IONM was independently associated with a lower risk of endocrine surgery-specific complications and greater likelihood of same-day discharge.

Hypoxia-altered cholesterol homeostasis enhances the expression of interferon-stimulated genes upon SARS-CoV-2 infections in monocytes

Hypoxia contributes to numerous pathophysiological conditions including inflammation-associated diseases. We characterized the impact of hypoxia on the immunometabolic cross-talk between cholesterol and interferon (IFN) responses. Specifically, hypoxia reduced cholesterol biosynthesis flux and provoked a compensatory activation of sterol regulatory element-binding protein 2 (SREBP2) in monocytes. Concomitantly, a broad range of interferon-stimulated genes (ISGs) increased under hypoxia in the absence of an inflammatory stimulus. While changes in cholesterol biosynthesis intermediates and SREBP2 activity did not contribute to hypoxic ISG induction, intracellular cholesterol distribution appeared critical to enhance hypoxic expression of chemokine ISGs. Importantly, hypoxia further boosted chemokine ISG expression in monocytes upon infection with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Mechanistically, hypoxia sensitized toll-like receptor 4 (TLR4) signaling to activation by SARS-CoV-2 spike protein, which emerged as a major signaling hub to enhance chemokine ISG induction following SARS-CoV-2 infection of hypoxic monocytes. These data depict a hypoxia-regulated immunometabolic mechanism with implications for the development of systemic inflammatory responses in severe cases of coronavirus disease-2019 (COVID-19).

Comparison of the Ct-values for genomic and subgenomic SARS-CoV-2 RNA reveals limited predictive value for the presence of replication competent virus

SARS-CoV-2 is the causative agent of the acute respiratory disease COVID-19. In addition to the full length positive-sensed, single-stranded genomic RNA (gRNA), viral subgenomic RNAs (sgRNAs) that are required for expression of the 3' region of the genome are synthesized in virus-infected cells. However, whether these sgRNA-species might be used as a measure of active virus replication and to predict infectivity is still under debate. The commonly used methods to monitor and quantitate SARS-CoV-2 infections are based on RT-qPCR analysis and the detection of gRNA. The infectivity of a sample obtained from nasopharyngeal or throat swabs is associated with the viral load and inversely correlates with Ct-values, however, a cut-off value predicting the infectivity highly depends on the performance of the assay. Furthermore, gRNA derived Ct-values result from nucleic acid detection and do not necessarily correspond to active replicating virus. We established a multiplex RT-qPCR assay on the cobas 6800 omni utility channel concomitantly detecting SARS-CoV-2 gRNA_Orf1a/b, sgRNA_E,7a,N, and human RNaseP-mRNA used as human input control. We compared the target specific Ct-values with the viral culture frequency and performed ROC curve analysis to determine the assay sensitivity and specificity. We found no advantage in the prediction of viral culture when using sgRNA detection compared to gRNA only, since Ct-values for gRNA and sgRNA were highly correlated and gRNA offered a slightly more reliable predictive value. Single Ct-values alone only provide a very limited prediction for the presence of replication competent virus. Hence, careful consideration of the medical history including symptom onset has to be considered for risk stratification.

Disease-Specific Survival Trends for Patients Presenting with Differentiated Thyroid Cancer and Distant Metastases in the United States, 1992-2018

Objective: Differentiated thyroid cancer (DTC) is associated with an excellent prognosis, but patients with distant metastatic DTC have a 10-year disease-specific survival (DSS) of just 50%. The incidence of distant metastatic DTC has steadily increased in the United States since the 1980s. The aim of this study was to examine trends in survival and treatment for patients with distant metastatic DTC. Methods: In this population-based, retrospective cohort study, patients with distant metastatic DTC were identified from the Surveillance, Epidemiology, and End Results-13 cancer registry program. Multivariable logistic and Cox regression analyses were used to examine factors associated with DSS and management. Annual percentage changes in treatment patterns were calculated using log-linear regression. Results: During 1992-2018, 1991 patients (69.7% white, 58.0% female, 47.5% aged ≥65 years) were diagnosed with distant metastatic DTC. Papillary thyroid cancer was the most common histological type (74.5%). While the 10-year DSS for overall DTC increased over time (95.4% for patients diagnosed in 1992-1998, 96.6% in 1999-2008, and 97.3% in 2009-2018; p < 0.01), 10-year DSS for DTC with distant metastases did not change (50.2%, 47.3%, and 52.4%, respectively; p = 0.48). Ten-year DSS rates were reduced for patients aged ≥65 years (28.1%), patients undergoing nonsurgical treatment with external beam radiation therapy and/or systemic therapy (6.0%), and patients undergoing no/unknown treatment (32.8%). On multivariable analysis, oncocytic carcinoma, age 65-79 and ≥80 years, male sex, node-positive disease, larger tumor size, nonsurgical treatment, and no/unknown treatment were associated with increased risk of thyroid cancer death. Between 1992 and 2018, the rate of nonsurgical treatment increased, on average, 1.3% per year (1992-1998: 22.9% vs. 2009-2018: 25.6%; p = 0.03), and the rate of patients receiving no/unknown treatment increased 1.9% per year (1992-1998: 11.3% vs. 2009-2018: 15.6%; p = 0.01). Patients aged 65-79 and ≥80 years were more likely than younger patients to receive nonsurgical management or no/unknown treatment. Conclusion: Patients diagnosed with distant metastatic DTC have experienced no improvement in DSS over the past three decades. An increasing proportion of patients diagnosed with distant metastatic DTC are receiving nonsurgical treatment or no/unknown treatment over time; the proportion was highest among the oldest patients.

NVX-CoV2373-induced cellular and humoral immunity towards parental SARS-CoV-2 and VOCs compared to BNT162b2 and mRNA-1273-regimens

BACKGROUND

The NVX-CoV2373-vaccine has recently been licensed, although knowledge on vaccine-induced humoral and cellular immunity towards the parental strain and variants of concern (VOCs) in comparison to mRNA-regimens is limited.

METHODS

In this observational study, 66 individuals were recruited to compare immunogenicity and reactogenicity of NVX-CoV2373 with BNT162b2 or mRNA-1273. Vaccine-induced antibodies were analyzed using ELISA and neutralization assays, specific CD4 and CD8 T-cells were characterized based on intracellular cytokine staining using flow-cytometry after antigen-specific stimulation with parental spike or VOCs.

RESULTS

Two doses of NVX-CoV2373 strongly induced anti-spike IgG, although IgG-levels were lower than after vaccination with BNT162b2 or mRNA-1273 (p = 0.006). Regardless of the vaccine and despite different IgG-levels, neutralizing activity towards VOCs was highest for Delta, followed by BA.2 and BA.1. The protein-based vaccine failed to induce any spike-specific CD8 T-cells which were detectable in 3/22 (14%) individuals only. In contrast, spike-specific CD4 T-cells were induced in 18/22 (82%) individuals, although their levels were lower (p<0.001), had lower CTLA-4 expression (p<0.0001) and comprised less multifunctional cells co-expressing IFNγ, TNFα and IL-2 (p = 0.0007). Unlike neutralizing antibodies, NVX-CoV2373-induced CD4 T-cells equally recognized all tested VOCs from Alpha to Omicron. In individuals with a history of infection, one dose of NVX-CoV2373 had similar immunogenicity as two doses in non-infected individuals. The vaccine was overall well tolerated.

CONCLUSION

NVX-CoV2373 strongly induced spike-specific antibodies and CD4 T-cells, albeit at lower levels as mRNA-regimens. Cross-reactivity of CD4 T-cells towards the parental strain and all tested VOCs may hold promise to protect from severe disease.

The prognostic significance of CXCR4 and SDF-1 in differentiated thyroid cancer depends on CD8+ density

BACKGROUND

Tumor infiltration with cytotoxic CD8+ T-cells is associated with a favorable outcome in several neoplasms, including thyroid cancer. The chemokine axis CXCR4/SDF-1 correlates with more aggressive tumors, but little is known concerning the prognostic relevance in relation to the tumor immune microenvironment of differentiated thyroid cancer (DTC).

METHODS

A tissue microarray (TMA) of 37 tumor specimens of primary DTC was analyzed by immunohistochemistry (IHC) for the expression of CD8+, CXCR4, phosphorylated CXCR4 and SDF-1. A survival analysis was performed on a larger collective (n = 456) at RNA level using data from The Cancer Genome Atlas (TCGA) papillary thyroid cancer cohort.

RESULTS

Among the 37 patients in the TMA-cohort, the density of CD8+ was higher in patients with less advanced primary tumors (median cells/TMA-punch: 12.5 (IQR: 6.5, 12.5) in T1-2 tumors vs. 5 (IQR: 3, 8) in T3-4 tumors, p = 0.05). In the TCGA-cohort, CXCR4 expression was higher in patients with cervical lymph node metastasis compared to N0 or Nx stage (CXCR4^high/low 116/78 vs. 97/116 vs. 14/35, respectively, p = 0.001). Spearman's correlation analysis of the TMA-cohort demonstrated that SDF-1 was significantly correlated with CXCR4 (r = 0.4, p = 0.01) and pCXCR4 (r = 0.5, p = 0.002). In the TCGA-cohort, density of CD8+ correlated with CXCR4 and SDF-1 expression (r = 0.58, p < 0.001; r = 0.4, p < 0.001). The combined marker analysis of the TCGA cohort demonstrated that high expression of both, CXCR4 and SDF-1 was associated with reduced overall survival in the CD8 negative TCGA cohort (p = 0.004).

CONCLUSION

These findings suggest that the prognostic significance of CXCR4 and SDF-1 in differentiated thyroid cancer depends on the density of CD8 positive T-lymphocytes. Further studies with larger sample sizes are needed to support our findings and inform future investigations of new treatment and diagnostic options for a more personalized approach for patients with differentiated thyroid cancer.

SRSF1 acts as an IFN-I-regulated cellular dependency factor decisively affecting HIV-1 post-integration steps

Efficient HIV-1 replication depends on balanced levels of host cell components including cellular splicing factors as the family of serine/arginine-rich splicing factors (SRSF, 1-10). Type I interferons (IFN-I) play a crucial role in the innate immunity against HIV-1 by inducing the expression of IFN-stimulated genes (ISGs) including potent host restriction factors. The less well known IFN-repressed genes (IRepGs) might additionally affect viral replication by downregulating host dependency factors that are essential for the viral life cycle; however, so far, the knowledge about IRepGs involved in HIV-1 infection is very limited. In this work, we could demonstrate that HIV-1 infection and the associated ISG induction correlated with low SRSF1 levels in intestinal lamina propria mononuclear cells (LPMCs) and peripheral blood mononuclear cells (PBMCs) during acute and chronic HIV-1 infection. In HIV-1-susceptible cell lines as well as primary monocyte-derived macrophages (MDMs), expression levels of SRSF1 were transiently repressed upon treatment with specific IFNα subtypes in vitro. Mechanically, 4sU labeling of newly transcribed mRNAs revealed that IFN-mediated SRSF1 repression is regulated on early RNA level. SRSF1 knockdown led to an increase in total viral RNA levels, but the relative proportion of the HIV-1 viral infectivity factor (Vif) coding transcripts, which is essential to counteract APOBEC3G-mediated host restriction, was significantly reduced. In the presence of high APOBEC3G levels, however, increased LTR activity upon SRSF1 knockdown facilitated the overall replication, despite decreased vif mRNA levels. In contrast, SRSF1 overexpression significantly impaired HIV-1 post-integration steps including LTR transcription, alternative splice site usage, and virus particle production. Since balanced SRSF1 levels are crucial for efficient viral replication, our data highlight the so far undescribed role of SRSF1 acting as an IFN-modulated cellular dependency factor decisively regulating HIV-1 post-integration steps.

Wastewater surveillance allows early detection of SARS-CoV-2 omicron in North Rhine-Westphalia, Germany

Wastewater-based epidemiology (WBE) has demonstrated its importance to support SARS-CoV-2 epidemiology complementing individual testing strategies. Due to their immune-evasive potential and the resulting significance for public health, close monitoring of SARS-CoV-2 variants of concern (VoC) is required to evaluate the regulation of early local countermeasures. In this study, we demonstrate a rapid workflow for wastewater-based early detection and monitoring of the newly emerging SARS-CoV-2 VoCs Omicron in the end of 2021 at the municipal wastewater treatment plant (WWTP) Emschermuendung (KLEM) in the Federal State of North-Rhine-Westphalia (NRW, Germany). Initially, available primers detecting Omicron-related mutations were rapidly validated in a central laboratory. Subsequently, RT-qPCR analysis of purified SARS-CoV-2 RNA was performed in a decentral PCR laboratory in close proximity to KLEM. This decentralized approach enabled the early detection of K417N present in Omicron in samples collected on 8th December 2021 and the detection of further mutations (N501Y, Δ69/70) in subsequent biweekly sampling campaigns. The presence of Omicron in wastewater was confirmed by next generation sequencing (NGS) in a central laboratory with samples obtained on 14th December 2021. Moreover, the relative increase of the mutant fraction of Omicron was quantitatively monitored over time by dPCR in a central PCR laboratory starting on 12th December 2021 confirming Omicron as the dominant variant by the end of 2021. In conclusions, WBE plays a crucial role in surveillance of SARS-CoV-2 variants and is suitable as an early warning system to identify variant emergence. In particular, the successive workflow using RT-qPCR, RT-dPCR and NGS demonstrates the strength of WBE as a versatile tool to monitor variant spreading.

Robotic versus laparoscopic low anterior resection following neoadjuvant chemoradiation therapy for stage II-III locally advanced rectal cancer: a single-centre cohort study

Neoadjuvant chemo-radiotherapy (nCRT) of locally advanced rectal cancer is associated with challenging surgical treatment and increased postoperative morbidity. Robotic technology overcomes laparoscopy limitations by enlarged 3D view, improved anatomical transection accuracy, and physiologic tremor reduction. Patients with UICC stage II-III rectal cancer, consecutively referred to our institution between March 2015 and June 2020 (n = 102) were treated with robotic (Rob-G, n = 38) or laparoscopic (Lap-G, n = 64) low anterior resection (LAR) for total meso-rectal excision (TME) following highly standardized and successful nCRT treatment. Feasibility, conversion rates, stoma creation, morbidity and clinical/pathological outcome were comparatively analysed. Sex, age, BMI, ASA scores, cTN stages and tumour distance from dentate line were comparable in the two groups. Robotic resection was always feasible without conversion to open surgery, which was necessary in 11/64 (17%) Lap-G operations (p = 0.006). Primary or secondary stomata were created in 17/38 (45%) Rob-G and 52/64 (81%) Lap-G patients (p < 0.001). Major morbidity occurred in 7/38 (18.4%) Rob-G and 6/64 (9.3%) Lap-G patients (p = 0.225). Although median operation time was longer in Rob-G compared with Lap-G (376; IQR: 330-417 min vs. 300; IQR: 270-358 min; p < 0.001), the difference was not significant in patients (Rob-G, n = 6; Lap-G, n = 10) with ≥30 BMI (p = 0.106). Number of resected lymph nodes, ypTN staging and circumferential resection margins (CRM) were comparable. Resection was complete in 87% of Rob-G and 89% of Lap-G patients (p = 0.750). Robotic LAR is not inferior to laparoscopic LAR following nCRT. Larger, randomized studies are needed to confirm lower conversion in robotic, compared to laparoscopic resection.

Molecular Analyses of Clinical Isolates and Recombinant SARS-CoV-2 Carrying B.1 and B.1.617.2 Spike Mutations Suggest a Potential Role of Non-Spike Mutations in Infection Kinetics

Some of the emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are less susceptible to neutralization with post-vaccine sera and monoclonal antibodies targeting the viral spike glycoprotein. This raises concerns of disease control, transmissibility, and severity. Numerous substitutions have been identified to increase viral fitness within the nucleocapsid and nonstructural proteins, in addition to spike mutations. Therefore, we sought to generate infectious viruses carrying only the variant-specific spike mutations in an identical backbone to evaluate the impact of spike and non-spike mutations in the virus life cycle. We used en passant mutagenesis to generate recombinant viruses carrying spike mutations of B.1 and B.1.617.2 variants using SARS-CoV-2- bacterial artificial chromosome (BAC). Neutralization assays using clinical sera yielded comparable results between recombinant viruses and corresponding clinical isolates. Non-spike mutations for both variants neither seemed to effect neutralization efficiencies with monoclonal antibodies nor the response to treatment with inhibitors. However, live-cell imaging and microscopy revealed differences, such as persisting syncytia and pronounced cytopathic effect formation, as well as their progression between BAC-derived viruses and clinical isolates in human lung epithelial cell lines and primary bronchial epithelial cells. Complementary RNA analyses further suggested a potential role of non-spike mutations in infection kinetics.

Endocrine surgeons are performing more thyroid lobectomies for low-risk differentiated thyroid cancer since the 2015 ATA guidelines

BACKGROUND

The 2015 American Thyroid Association guidelines recommended either total thyroidectomy or lobectomy for surgical treatment of low-risk differentiated thyroid cancer and de-escalated recommendations for central neck dissections. The study aim was to investigate how practice patterns among endocrine surgeons have changed over time.

METHODS

All adult patients with low-risk differentiated thyroid cancers (T1-T2, N0/Nx, M0/Mx) in the Collaborative Endocrine Surgery Quality Improvement Program (2014-2021) were identified. The outcomes between patients undergoing lobectomy versus total thyroidectomy were compared using multivariable logistic regression. The annual percent change in the proportion of lobectomies and central neck dissections performed was estimated using joinpoint regression.

RESULTS

In total, 5,567 patients with low-risk differentiated thyroid cancers were identified. Of these, 2,261 (40.6%) were very low-risk tumors ≤1 cm, and 2,983 (53.6%) were low-risk tumors >1 and <4 cm. Most patients (67.9%) underwent total thyroidectomy. Compared to total thyroidectomy, lobectomy was associated with outpatient surgery (adjusted odds ratio 5.19, P < .001), a decreased risk of postoperative emergency department visits (adjusted odds ratio 0.63, P = .03), and decreased risk of hypoparathyroidism events (adjusted odds ratio 0.03, P < .001). Compared to before (2014-2015), patients undergoing surgery after publication of the revised guidelines (2016-2021) had higher odds of lobectomy and lower odds of central neck dissection for tumors ≤1 cm (lobectomy adjusted odds ratio 2.70, P < .001; central neck dissections adjusted odds ratio 0.64, P = .03) and tumors between 1 and 4 cm (lobectomy adjusted odds ratio 2.27, P < .001; central neck dissection adjusted odds ratio 0.62, P < .001).

CONCLUSION

After publication of the 2015 American Thyroid Association guidelines, there has been an increase in thyroid lobectomies as a proportion of all thyroid operations performed by endocrine surgeons for low-risk differentiated thyroid cancer. This has implications for reduced health care use and costs, with potential population-level benefits.

Limited neutralisation of the SARS-CoV-2 Omicron subvariants BA.1 and BA.2 by convalescent and vaccine serum and monoclonal antibodies

BACKGROUND

In recent months, Omicron variants of SARS-CoV-2 have become dominant in many regions of the world, and case numbers with Omicron subvariants BA.1 and BA.2 continue to increase. Due to numerous mutations in the spike protein, the efficacy of currently available vaccines, which are based on Wuhan-Hu 1 isolate of SARS-CoV-2, is reduced, leading to breakthrough infections. Efficacy of monoclonal antibody therapy is also likely impaired.

METHODS

In our in vitro study using A549-AT cells constitutively expressing ACE2 and TMPRSS2, we determined and compared the neutralizing capacity of vaccine-elicited sera, convalescent sera and monoclonal antibodies against authentic SARS-CoV-2 Omicron BA.1 and BA.2 compared with Delta.

FINDINGS

Almost no neutralisation of Omicron BA.1 and BA.2 was observed using sera from individuals vaccinated with two doses 6 months earlier, regardless of the type of vaccine taken. Shortly after the booster dose, most sera from triple BNT162b2-vaccinated individuals were able to neutralise both Omicron variants. In line with waning antibody levels three months after the booster, only weak residual neutralisation was observed for BA.1 (26%, n = 34, 0 median NT₅₀) and BA.2 (44%, n = 34, 0 median NT₅₀). In addition, BA.1 but not BA.2 was resistant to the neutralising monoclonal antibodies casirivimab/imdevimab, while BA.2 exhibited almost a complete evasion from the neutralisation induced by sotrovimab.

INTERPRETATION

Both SARS-CoV-2 Omicron subvariants BA.1 and BA.2 escape antibody-mediated neutralisation elicited by vaccination, previous infection with SARS-CoV-2, and monoclonal antibodies. Waning immunity renders the majority of tested sera obtained three months after booster vaccination negative in BA.1 and BA.2 neutralisation. Omicron subvariant specific resistance to the monoclonal antibodies casirivimab/imdevimab and sotrovimab emphasizes the importance of genotype-surveillance and guided application.

FUNDING

This study was supported in part by the Goethe-Corona-Fund of the Goethe University Frankfurt (M.W.) and the Federal Ministry of Education and Research (COVIDready; grant 02WRS1621C (M.W.).

Characterization of the Antibody and Interferon-Gamma Release Response after a Second COVID-19 Booster Vaccination

The emergence of SARS-CoV-2 Omicron subvariants prompted countries to call for accelerated booster vaccinations to limit disease and transmission. Here, we characterized correlates of protection over time after the second booster or after Omicron BA.1 infection comparing variants of concern (VOCs). Sera from subjects before and two and seven weeks after the second booster or after Omicron infection were examined for the level of Spike receptor-binding-domain (RBD)-specific antibodies. Furthermore, neutralizing antibodies (nABs) were characterized in in vitro neutralization assays comparing the variants of concern Alpha, Beta, Delta, and Omicron BA.1 and BA.2 against the ancestral strain B.1. Here, the second booster resulted in an increase in anti-RBD-IgG-antibodies, remaining nearly constant over time, accompanied by an increase in nABs against B.1 and the VOCs Alpha, Beta, Delta, and Omicron BA.1 and BA.2. However, compared to B.1, the neutralizing capacity against the Omicron subvariants remained low and was limited after the second booster vaccination. This indicates that antibody-mediated protection against infection with this VOC is unlikely, as evidenced by the fact that three individuals of our study cohort became infected with Omicron BA.1 after the second booster. T cell activation was measured by interferon-gamma release assays in a subgroup of subjects and was increased in all subjects tested after the second booster vaccination, correlating with the amount of Spike-specific antibodies. In subjects with Omicron BA.1 breakthrough infection, a significant increase in nABs to all VOCs studied was observed independently of booster vaccinations. Taken together, our data indicate that a second booster or Omicron BA.1 infection mediate a substantial increase in anti-Spike IgG antibodies; however, infection with Omicron BA.1 induced a stronger increase in neutralizing antibodies against the different VOCs

From open Ivor Lewis esophagectomy to a hybrid robotic-assisted thoracoscopic approach: a single-center experience over two decades

PURPOSE

Robotic-assisted procedures are increasingly used in esophageal cancer surgery. We compared postoperative complications and early oncological outcomes following hybrid robotic-assisted thoracoscopic esophagectomy (Rob-E) and open Ivor Lewis esophagectomy (Open-E), performed in a single mid-volume center, in the context of evolving preoperative patient and tumor characteristics over two decades.

METHODS

We evaluated prospectively collected data from a single center from 1999 to 2020 including 321 patients that underwent Ivor Lewis esophagectomy, 76 underwent Rob-E, and 245 Open-E. To compare perioperative outcomes, a 1:1 case-matched analysis was performed. Endpoints included postoperative morbidity and 30-day mortality.

RESULTS

Preoperative characteristics revealed increased rates of adenocarcinomas and wider use of neoadjuvant treatment over time. A larger number of patients with higher ASA grades were operated with Rob-E. In case-matched cohorts, there were no differences in the overall morbidity (69.7% in Rob-E, 60.5% in Open-E, p value 0.307), highest Clavien-Dindo grade per patient (43.4% vs. 38.2% grade I or II, p value 0.321), comprehensive complication index (median 20.9 in both groups, p value 0.401), and 30-day mortality (2.6% in Rob-E, 3.9% in Open-E, p value 1.000). Similar median numbers of lymph nodes were harvested (24.5 in Rob-E, 23 in Open-E, p value 0.204), and comparable rates of R0-status (96.1% vs. 93.4%, p value 0.463) and distribution of postoperative UICC stages (overall p value 0.616) were observed.

CONCLUSIONS

Our study demonstrates similar postoperative complications and early oncological outcomes after Rob-E and Open-E. However, the selection criteria for Rob-E appeared to be less restrictive than those of Open-E surgery.

Detection and Quantification of SARS-CoV-2 by Real-Time RT-PCR Assay

The pandemic coronavirus SARS-CoV-2 is the causative agent of the acute respiratory disease COVID-19, which has become a global concern due to its rapid spread and high mortality rate. Detection and quantification of the (+) ssRNA virus, which has a genome size of 29,903 nucleotides, is commonly performed via reverse transcription quantitative polymerase chain reaction (RT-qPCR) targeting conserved sequences. Here, we describe a one-step RT-qPCR protocol for the quantitative detection of SARS-CoV-2 genomic RNA targeting M and RdRP genes, respectively, as well as active virus replication detecting subgenomic RNAs (sgRNA 4 and 8) that are formed by discontinuous transcription of the viral genome. Concomitantly, an input control targeting the human RNaseP gene (RPP30) was used in multiplex PCR to monitor the input of human nucleic acids. In vitro-transcribed RNA harboring the amplicon regions for M and RdRP regions served to set up a standard curve for absolute quantification.In conclusion, the method described here allows for the detection and quantification of SARS-CoV-2 RNA isoforms for research by both using a probe-based or SYBR Green-based approach, but is also suitable for diagnostic purposes.

Cytokeratin 7 and Copper Stains Facilitate Diagnosis of Small Duct Primary Sclerosing Cholangitis

Introduction/Objective

Classic primary sclerosing cholangitis (PSC) involves extrahepatic and/or intrahepatic biliary ducts with segmental biliary strictures and dilatations that often allow the diagnosis to be made via cholangiogram. Small duct PSC (sdPSC) is a rare subtype that presents similarly with a cholestatic pattern of injury, yet due to the small size of involved ducts, a cholangiogram is non-diagnostic and diagnosis is dependent on clinical suspicion and liver biopsy. The histopathological features of sdPSC are often subtle and may easily be overlooked. Diagnosis of this entity- though difficult- is important, as early recognition can facilitate the identification of associated disease processes and life-threatening complications.

Methods/Case Report

We encountered a 33-year-old female presenting with intermittent pruritis, episodes of jaundice, and persistently elevated alkaline phosphatase who was misdiagnosed with only fatty liver at an outside institution. Evaluation with MRCP showed no abnormalities within the biliary tract and a liver biopsy was performed to aid in the diagnosis. The H&E and trichrome findings of atrophic bile ducts and some peribiliary sclerosis were extremely subtle and may have been overlooked without clinical suspicion. Cytokeratin 7 (CK7) highlighted cholangiolar metaplasia in hepatocytes and the bile ductular reaction that occurs in cholestatic disease states. A Rhodamine copper stain showed periportal deposition suggestive of chronic biliary obstruction. Use of CK7 and copper stains supported the presence of chronic biliary injury and suboptimal bile flow, confirming the diagnosis of sdPSC.

Results (if a Case Study enter NA)

NA

Conclusion

Diagnosis of sdPSC has historically relied on H&E and trichrome stains. In this case, the findings on H&E and trichrome stains were non-diagnostic, while the use of CK7 and copper stains confirmed the diagnosis of sdPSC. We recommend using CK7 and copper stains to evaluate for sdPSC.

Non-IgG4-Related Fibrosing Mediastinitis Diagnosed on Needle Biopsy and Treated with Steroids

Introduction/Objective

Fibrosing mediastinitis (FM) is a rare and aggressive fibroinflammatory process of the mediastinum. It is a difficult diagnosis, especially on small biopsies as the presentation and the fibrosing background mimics malignancy. Although the exact etiology is unknown, prior fungal infections, certain medications and autoimmune conditions are documented. Significant histopathologic overlap with IgG4-related disease (IgG4-RD) can complicate the diagnosis. An accurate diagnosis is important for treatment as corticosteroids for IgG4-RD is proven to be effective; however, no effective treatment is described for FM. Additionally, immunosuppression would prove harmful in other conditions with fibrosing morphology. We report a very unique case of non-IgG4-related FM that was diagnosed on a needle biopsy and showed marked improvement with corticosteroids.

Methods/Case Report

A 65-year-old man with no significant medical history presented with syncope and recent weight loss. Imaging revealed a pericardial effusion and a heterogeneous 8.1 cm mediastinal mass encasing the great vessels and aortic arch. Needle biopsy showed fibrosis with keloid-type collagen, mixed inflammatory cells, and few benign lymphoid follicles. No evidence of hematolymphoid malignancy, carcinoma, or infection was seen. Serum and tissue IgG-4 studies were negative for IgG4-RD. A diagnosis of FM was made, and a trial of corticosteroids was initiated. Interestingly, the patient showed improvement with a 2.3 cm decrease in lesion size and near-complete resolution of pericardial effusion after one month of treatment.

Results (if a Case Study enter NA)

NA

Conclusion

FM should be included in the differential diagnosis of infiltrative mediastinal masses which presents a diagnostic challenge on limited needle biopsies. Although effective treatment for non-IgG4 related FM is not clearly established, corticosteroids may prove beneficial, as in this patient. Mortality from FM is directly related to the compressive effect on adjacent structures. Early diagnosis and treatment are therefore crucial. Further studies on the pathogenesis are necessary, as well as better directed therapeutic options.

Antibody-Mediated Neutralization of Authentic SARS-CoV-2 B.1.617 Variants Harboring L452R and T478K/E484Q

The capacity of convalescent and vaccine-elicited sera and monoclonal antibodies (mAb) to neutralize SARS-CoV-2 variants is currently of high relevance to assess the protection against infections. We performed a cell culture-based neutralization assay focusing on authentic SARS-CoV-2 variants B.1.617.1 (Kappa), B.1.617.2 (Delta), B.1.427/B.1.429 (Epsilon), all harboring the spike substitution L452R. We found that authentic SARS-CoV-2 variants harboring L452R had reduced susceptibility to convalescent and vaccine-elicited sera and mAbs. Compared to B.1, Kappa and Delta showed a reduced neutralization by convalescent sera by a factor of 8.00 and 5.33, respectively, which constitutes a 2-fold greater reduction when compared to Epsilon. BNT2b2 and mRNA1273 vaccine-elicited sera were less effective against Kappa, Delta, and Epsilon compared to B.1. No difference was observed between Kappa and Delta towards vaccine-elicited sera, whereas convalescent sera were 1.51-fold less effective against Delta, respectively. Both B.1.617 variants Kappa (+E484Q) and Delta (+T478K) were less susceptible to either casirivimab or imdevimab. In conclusion, in contrast to the parallel circulating Kappa variant, the neutralization efficiency of convalescent and vaccine-elicited sera against Delta was moderately reduced. Delta was resistant to imdevimab, which, however, might be circumvented by combination therapy with casirivimab together.

Antibody-Mediated Neutralization of Authentic SARS-CoV-2 B.1.617 Variants Harboring L452R and T478K/E484Q

The capacity of convalescent and vaccine-elicited sera and monoclonal antibodies (mAb) to neutralize SARS-CoV-2 variants is currently of high relevance to assess the protection against infections. We performed a cell culture-based neutralization assay focusing on authentic SARS-CoV-2 variants B.1.617.1 (Kappa), B.1.617.2 (Delta), B.1.427/B.1.429 (Epsilon), all harboring the spike substitution L452R. We found that authentic SARS-CoV-2 variants harboring L452R had reduced susceptibility to convalescent and vaccine-elicited sera and mAbs. Compared to B.1, Kappa and Delta showed a reduced neutralization by convalescent sera by a factor of 8.00 and 5.33, respectively, which constitutes a 2-fold greater reduction when compared to Epsilon. BNT2b2 and mRNA1273 vaccine-elicited sera were less effective against Kappa, Delta, and Epsilon compared to B.1. No difference was observed between Kappa and Delta towards vaccine-elicited sera, whereas convalescent sera were 1.51-fold less effective against Delta, respectively. Both B.1.617 variants Kappa (+E484Q) and Delta (+T478K) were less susceptible to either casirivimab or imdevimab. In conclusion, in contrast to the parallel circulating Kappa variant, the neutralization efficiency of convalescent and vaccine-elicited sera against Delta was moderately reduced. Delta was resistant to imdevimab, which, however, might be circumvented by combination therapy with casirivimab together.

Generation of a Sleeping Beauty Transposon-Based Cellular System for Rapid and Sensitive Screening for Compounds and Cellular Factors Limiting SARS-CoV-2 Replication

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the acute respiratory disease COVID-19, which has become a global concern due to its rapid spread. The common methods to monitor and quantitate SARS-CoV-2 infectivity in cell culture are so far time-consuming and labor-intensive. Using the Sleeping Beauty transposase system, we generated a robust and versatile cellular infection model that allows SARS-CoV-2 infection experiments compatible for high-throughput and live cell imaging. The model is based on lung derived A549 cells, which show a profound interferon response and convenient cell culture characteristics. ACE2 and TMPRSS2 were introduced for constitutive expression (A549-AT). Subclones with varying levels of ACE2/TMPRSS2 were screened for optimal SARS-CoV-2 susceptibility. Furthermore, extensive evaluation demonstrated that SARS-CoV-2 infected A549-AT cells were distinguishable from mock-infected cells and already showed approximately 12 h post infection a clear signal to noise ratio in terms of cell roughness, fluorescence and a profound visible cytopathic effect. Moreover, due to the high transfection efficiency and proliferation capacity, Sleeping Beauty transposase-based overexpression cell lines with a second inducible fluorescence reporter cassette (eGFP) can be generated in a very short time, enabling the investigation of host and restriction factors in a doxycycline-inducible manner. Thus, the novel model cell line allows rapid and sensitive monitoring of SARS-CoV-2 infection and the screening for host factors essential for viral replication.

Limited neutralization of authentic SARS-CoV-2 variants carrying E484K in vitro

Whether monoclonal antibodies are able to neutralise SARS-CoV-2 variants of concern has been investigated using pseudoviruses. In this study we show that bamlanivimab, casirivimab, and imdevimab efficiently neutralise authentic SARS-CoV-2 including variant B.1.1.7 (Alpha) but variants B.1.351 (Beta) and P.2 (Zeta) were resistant against bamlanivimab and partially to casirivimab.

Robot-assisted vs. laparoscopic repair of complete upside-down stomach hiatal hernia (the RATHER-study): A prospective comparative single center study

Objective

Complete upside-down stomach (cUDS) hernias are a subgroup of large hiatal hernias characterized by high risk of life-threatening complications and technically challenging surgical repair including complex mediastinal dissection. In a prospective, comparative clinical study, we evaluated intra- and postoperative outcomes, quality of life and symptomatic recurrence rates in patients with cUDS undergoing robot-assisted, as compared to standard laparoscopic repair (the RATHER-study).

Methods

All patients with cUDS herniation requiring elective surgery in our institution between July 2015 and June 2019 were evaluated. Patients undergoing primary open surgery or additional associated procedures were not considered. Primary endpoints were intra- and postoperative complications, 30-day morbidity, and mortality. During the 8-53 months follow-up period, patients were contacted by telephone to assess symptoms associated to recurrence, whereas quality of life was evaluated utilizing the Gastroesophageal Reflux Disease–Health-Related Quality of Life (GERD-HRQL) questionnaire.

Results

A total of 55 patients were included. 36 operations were performed with robot-assisted (Rob-G), and 19 with standard laparoscopic (Lap-G) technique. Patients characteristics were similar in both groups. Median operation time was 232 min. (IQR: 145-420) in robot-assisted vs. 163 min. (IQR:112-280) in laparoscopic surgery (p &lt; 0.001). Intraoperative complications occurred in 5/36 (12.5%) cases in the Rob-G group and in 5/19 (26%) cases in the Lap-G group (p = 0.28). No conversion was necessary in either group. Minor postoperative complications occurred in 13/36 (36%) Rob-G patients and 4/19 (21%) Lap-G patients (p = 0.36). Mortality or major complications did not occur in either group. Two asymptomatic recurrences were observed in the Rob-G group only. No patient required revision surgery. Finally, all patients expressed satisfaction for treatment outcome, as indicated by similar GERD-HRQL scores.

Conclusion

While robot-assisted surgery provides additional precision, enhanced visualization, and greater feasibility in cUDS hiatal hernia repair, its clinical outcome is at least equal to that obtained by standard laparoscopic surgery.

High expression of CD34 protein in stage IIA rectal cancer is independently associated with better prognosis

Objective

Colorectal cancer (CRC) remains the third most common cause of death from malignancies, while 30% of all these tumors develop in the rectum. The proximity of the rectum to vital structures, and in some cases the use of neoadjuvant treatment, make the surgical resection of this tumor a great challenge even for highly qualified surgeons. Understanding the mechanisms of rectal cancer (RC) development could lead to new concepts in the approach of diagnosis, prognosis, and eventually treatment of this disease. Despite the fact that TNM classification represents the gold standard tool for the staging of RC, a significant number of studies has recently focused on the association between the tumor microenvironment and RC. CD34 is a transmembrane phosphoglycoprotein expressed on human hematopoietic progenitor and vascular endothelial cells, as well in malignant tissues. It has also been shown to be involved in tumor invasion and angiogenesis. Because of the controversial data , we examined the expression of CD34 protein in RC specimens after stratifying the patients according to their UICC stage.

Methods

In our retrospective study, we included 364 patients with unselected, clinically annotated primary RC specimens. We analyzed a tissue microarray (TMA) of these specimens by immunohistochemistry (IHC) for the expression of CD34 protein by tumor cells.

Results

After stratifying the patients in nodal negative and positive groups, we found that the patients with Stage IIA tumors and high expression of CD34 protein had a favorable 5-year overall survival rate (53%; 95%CI = 40.0 – 65.1%) compared to tumors without expression of CD34 protein (26%; 95%CI = 10.7 – 44.6%, p = 0.003). Univariate and multivariate Hazard Cox regression survival analysis revealed that the combined the expression of CD34 protein was an independent, favorable, prognostic marker for overall survival in the stage IIA RC (HR = 0.39, 95%CI = 0.19 – 0.79; p = 0.009).

Conclusion

Our data show that the expression of CD34 protein represents an independent, favorable, prognostic condition in nodal negative stage IIA RC. Thereby, we provide novel insights into the prognostic role of the tumor microenvironment in RC that might help in the development of novel treatment modalities by its modification.

Robot-assisted vs. laparoscopic repair of complete upside-down stomach hiatal hernia (the RATHER-study): a prospective comparative single center study

BACKGROUND

Complete upside-down stomach (cUDS) hernias are a subgroup of large hiatal hernias characterized by high risk of life-threatening complications and technically challenging surgical repair including complex mediastinal dissection. In a prospective, comparative clinical study, we evaluated intra- and postoperative outcomes, quality of life and symptomatic recurrence rates in patients with cUDS undergoing robot-assisted, as compared to standard laparoscopic repair (the RATHER-study).

METHODS

All patients with cUDS herniation requiring elective surgery in our institution between July 2015 and June 2019 were evaluated. Patients undergoing primary open surgery or additional associated procedures were not considered. Primary endpoints were intra- and postoperative complications, 30-day morbidity, and mortality. During the 8-53 months follow-up period, patients were contacted by telephone to assess symptoms associated to recurrence, whereas quality of life was evaluated utilizing the Gastroesophageal Reflux Disease-Health-Related Quality of Life (GERD-HRQL) questionnaire.

RESULTS

A total of 55 patients were included. 36 operations were performed with robot-assisted (Rob-G), and 19 with standard laparoscopic (Lap-G) technique. Patients characteristics were similar in both groups. Median operation time was 232 min. (IQR: 145-420) in robot-assisted vs. 163 min. (IQR:112-280) in laparoscopic surgery (p < 0.001). Intraoperative complications occurred in 5/36 (12.5%) cases in the Rob-G group and in 5/19 (26%) cases in the Lap-G group (p = 0.28). No conversion was necessary in either group. Minor postoperative complications occurred in 13/36 (36%) Rob-G patients and 4/19 (21%) Lap-G patients (p = 0.36). Mortality or major complications did not occur in either group. Two asymptomatic recurrences were observed in the Rob-G group only. No patient required revision surgery. Finally, all patients expressed satisfaction for treatment outcome, as indicated by similar GERD-HRQL scores.

CONCLUSION

While robot-assisted surgery provides additional precision, enhanced visualization, and greater feasibility in cUDS hiatal hernia repair, its clinical outcome is at least equal to that obtained by standard laparoscopic surgery.

Prognostic significance of CD8+ T-cells density in stage III colorectal cancer depends on SDF-1 expression

Since colorectal cancer (CRC) remains one of the most common malignancies, a tremendous amount of studies keep taking place in this field. Over the past 25 years, a notable part of the scientific community has focused on the association between the immune system and colorectal cancer. A variety of studies have shown that high densities of infiltrating CD8+ T-cells are associated with improved disease-free and overall survival in CRC. Stromal cell-derived factor-1 (SDF-1) is a protein that regulates leukocyte trafficking and is variably expressed in several healthy and malignant tissues. There is strong evidence that SDF-1 has a negative prognostic impact on a variety of solid tumors. However, the existing data do not provide sufficient evidence that the expression of SDF-1 has an influence on CRC. Knowing nowadays, that the microenvironment plays a crucial role in the development of cancer, we hypothesized that the expression of SDF-1 in CRC could influence the prognostic significance of CD8+ T-cells, as an indicator of the essential role of the immune microenvironment in cancer development. Therefore, we explored the combined prognostic significance of CD8+ T-cell density and SDF-1 expression in a large CRC collective. We analyzed a tissue microarray of 613 patient specimens of primary CRCs by immunohistochemistry (IHC) for the CD8 + T-cells density and the expression of SDF-1 by tumor cells and tumor-infiltrating immune cells. Besides, we analyzed the expression of SDF-1 at the RNA level in The Cancer Genome Atlas cohort. We found that the combined high CD8+ T-cell infiltration and expression of SDF-1 shows a favorable 5-year overall survival rate (66%; 95% CI 48-79%) compared to tumors showing a high expression of CD8+ T-cell only (55%; 95% CI 45-64%; p = 0.0004). After stratifying the patients in nodal negative and positive groups, we found that the prognostic significance of CD8+ T-cell density in nodal positive colorectal cancer depends on SDF-1 expression. Univariate and multivariate Hazard Cox regression survival analysis considering the combination of both markers revealed that the combined high expression of SDF-1 and CD8+ T-cell density was an independent, favorable, prognostic marker for overall survival (HR = 0.34, 95% CI 0.17-0.66; p = 0.002 and HR = 0.45, 95% CI 0.23-0.89; p = 0.021, respectively). In our cohort there was a very weak correlation between SDF-1 and CD8+ T-cells (rs = 0.13, p = 0.002) and in the trascriptomic expression of these two immune markers display a weak correlation (rs = 0.28, p < 0.001) which was significantly more pronounced in stage III cancers (rs = 0.40, p < 0.001). The combination of high CD8+ T-cell density and expression of SDF-1 represents an independent, favorable, prognostic condition in CRC, mostly in patients with stage III disease.

Papain-like protease regulates SARS-CoV-2 viral spread and innate immunity

The papain-like protease PLpro is an essential coronavirus enzyme that is required for processing viral polyproteins to generate a functional replicase complex and enable viral spread1,2. PLpro is also implicated in cleaving proteinaceous post-translational modifications on host proteins as an evasion mechanism against host antiviral immune responses3-5. Here we perform biochemical, structural and functional characterization of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PLpro (SCoV2-PLpro) and outline differences with SARS-CoV PLpro (SCoV-PLpro) in regulation of host interferon and NF-κB pathways. SCoV2-PLpro and SCoV-PLpro share 83% sequence identity but exhibit different host substrate preferences; SCoV2-PLpro preferentially cleaves the ubiquitin-like interferon-stimulated gene 15 protein (ISG15), whereas SCoV-PLpro predominantly targets ubiquitin chains. The crystal structure of SCoV2-PLpro in complex with ISG15 reveals distinctive interactions with the amino-terminal ubiquitin-like domain of ISG15, highlighting the high affinity and specificity of these interactions. Furthermore, upon infection, SCoV2-PLpro contributes to the cleavage of ISG15 from interferon responsive factor 3 (IRF3) and attenuates type I interferon responses. Notably, inhibition of SCoV2-PLpro with GRL-0617 impairs the virus-induced cytopathogenic effect, maintains the antiviral interferon pathway and reduces viral replication in infected cells. These results highlight a potential dual therapeutic strategy in which targeting of SCoV2-PLpro can suppress SARS-CoV-2 infection and promote antiviral immunity.

Localization of Drosophila CENP-A to non-centromeric sites depends on the NuRD complex

Centromere function requires the presence of the histone H3 variant CENP-A in most eukaryotes. The precise localization and protein amount of CENP-A are crucial for correct chromosome segregation, and misregulation can lead to aneuploidy. To characterize the loading of CENP-A to non-centromeric chromatin, we utilized different truncation- and localization-deficient CENP-A mutant constructs in Drosophila melanogaster cultured cells, and show that the N-terminus of Drosophila melanogaster CENP-A is required for nuclear localization and protein stability, and that CENP-A associated proteins, rather than CENP-A itself, determine its localization. Co-expression of mutant CENP-A with its loading factor CAL1 leads to exclusive centromere loading of CENP-A whereas co-expression with the histone-binding protein RbAp48 leads to exclusive non-centromeric CENP-A incorporation. Mass spectrometry analysis of non-centromeric CENP-A interacting partners identified the RbAp48-containing NuRD chromatin remodeling complex. Further analysis confirmed that NuRD is required for ectopic CENP-A incorporation, and RbAp48 and MTA1-like subunits of NuRD together with the N-terminal tail of CENP-A mediate the interaction. In summary, our data show that Drosophila CENP-A has no intrinsic specificity for centromeric chromatin and utilizes separate loading mechanisms for its incorporation into centromeric and ectopic sites. This suggests that the specific association and availability of CENP-A interacting factors are the major determinants of CENP-A loading specificity.

Synthesis and Bioactivity of Reduced Chalcones Containing Sulfonamide Side Chains

The effect on the bioactivity of antibacterial sulfonamide drugs against malaria and tuberculosis via an increase of the lipid solubility groups by condensation with a reduced chalcone was investigated. Sulfonamide derivatives (8a-8d) were obtained via a 1,3-diarylpropane scaffold, prepared by reduction of the relevant chalcones, followed by the addition of a sulfonamide moiety via the Mannich and the Mannich exchange reactions. The ClogP values indicated that the lipophilicities of 8a-8d and intermediate reduced chalcones and N-alkylated reduced chalcones (5a-7a) were much higher than those of the sulfonamides (1a-1c). The N-alkylated reduced chalcone derivatives 6 and 7 exhibited the highest antimalarial (Plasmodium falciparum (NF54 strain)) activity. Addition of the sulfonamide group weakened the activity, even though some ClogP values were higher, while 1a-1c showed no activity. The reduced chalcones 5a and 5 showed potent growth inhibition of Mycobacterium tuberculosis (H37Rv strain), but the sulfonamide derivatives 8a and 8d showed no or insignificant activity (0 and 14%, respectively) against M. tuberculosis, despite high ClogP values. Thus, the possible increase in bioactivity expected from an increase in ClogP values (lipophilicity) might be counteracted by the higher molecular weight of the studied analogues.

Residual kidney function after donor nephrectomy

Aim: We evaluated the long-term residual renal function after donor nephrectomy using 99mTc-mercaptoacetyltriglycin (MAG3)-clearance. Donors, methods: Altogether 49 kidney donors were examined using 99mTc-MAG3-clearance after nephrectomy for donation to a relative (m:f = 11:38; age 55±27 years). The donors were examined 16±8 years postoperatively (1.5-26 years). 42 donors (86%) showed normal creatinine values, whereas the other seven (14%) exhibited slightly elevated levels. 20 donors were examined pre- and postoperatively and compared intraindividually. The kidney function was compared to the age adapted normal values of healthy persons with two kidneys (67–133% of age related mean). Results: After nephrectomy all donors showed a normal perfusion, good secretion, merely physiological intrarenal transit and a normal elimination from the kidneys. The 99mTc-MAG3-clearance was 69 ±15% of the normal mean value of healthy carriers of two kidneys regardless of the gender. 20 donors with a preoperative examination showed a significantly reduced total renal function from 84 ± 15% of the mean normal value preoperatively to 60 ± 15% postoperatively (p <0.0005). 15 donors of this group exhibited a significant functional increase of the residual kidney from 40% initially to 60% after nephrectomy (p = 0.003). No correlation was found between the initial 99mTc-MAG3-clearance measured prior to nephrectomy and the clearance levels after nephrectomy. Also, no correlation between the preoperative 99mTc- MAG3-clearance and the postoperative serum creatinine values could be observed. Altogether, 22% of the donors (11/49) developed arterial hypertension 10 ± 8 years after donation (1-23 years). This corresponds to the normal age prevalence of hypertension in the carriers of two kidneys. Three donors suffered from arterial hypertension prior to the operation. Conclusion: Kidney donors with normal or slightly elevated creatinine values postoperatively show a 99mTc- MAG3-clearance value of 69% of the mean value of healthy carriers of two kidneys. This may serve as a reference value for healthy carriers of one kidney. In our study we demonstrated a good compensation of the contralateral kidney via renal scintigraphy by means of 99mTc-MAG3-clearance.

Five years of experience with the FiLaC™ laser for fistula-in-ano management: long-term follow-up from a single institution

Background

There are limited data available concerning endofistular therapies for fistula-in-ano, with our group reporting the first preliminary outcomes of the use of the radial fibre Fistula laser Closing (FiLaC ™) device.

Methods

The aim of this study was to assess a cohort of anal fistulae managed with laser ablation plus definitive flap closure of the internal fistula opening over a long-term follow-up. Factors governing primary healing success and secondary healing success (i.e. success after one or two operations) were determined.

Results

The study analysed 117 patients over a median follow-up period of 25.4 months (range 6–60 months) with 13 patients (11.1%) having Crohn’s-related fistulae. No incontinence to solid and liquid stool was reported. Minor incontinence to mucus and gas was observed in two cases (1.7%), and a late abscess treated in one case (0.8%). The primary healing rate was 75/117 (64.1%) overall, and 63.5% for cryptoglandular fistulae versus 69.2% for Crohn’s fistulae, respectively. Of the 42 patients who failed FiLaC™ 31 underwent a second operation (“Re-FiLaC™”, fistulectomy with sphincter reconstruction or fistulotomy). The secondary healing rate, defined as healing of the fistula at the end of the study period, was 103/117 (88.0%) overall and 85.5% for cryptoglandular fistulae versus 92.3% for Crohn’s fistulae. A significantly higher primary success rate was observed for intersphincteric-type fistulae with primary and secondary outcome unaffected by age, gender, presence of Crohn’s disease, number of prior surgeries and the type of flap designed to close the internal fistula opening.

Conclusions

There is a moderate primary success rate using first-up FiLaC™ treatment. If FiLaC™ fails, secondary success with repeat FiLaC™ or other approaches was high. The minimally invasive FiLaC™ approach may therefore represent a sensible first-line treatment option for anal fistula repair.

[The influence of VEGF inhibitors on corneal endothelium after injection into the anterior chamber in a porcine eye model]

BACKGROUND

The injection of antiangiogenic agents, such as ranibizumab (Lucentis®) and bevacizumab (Avastin®) into the anterior chamber of the eye represents a suitable alternative for treating neovascular glaucoma by reducing intraocular pressure.

OBJECTIVES

As the antiangiogenic substances are in direct contact with the sensitive corneal endothelium, the aim of this study was to show the effects of intracameral injection of ranibizumab and bevacizumab on this cell layer.

METHODS

Each injection consisted of 50 µl containing either ranibizumab (0.5 mg/0.05 ml), bevacizumab (1.25 mg/0.05 ml) or triamcinolone containing benzyl alcohol (2 mg/0.05 ml) which was used as the control group. These compounds were injected into the anterior chamber of pig eyes. Afterwards the corneas were dissected, fixed, examined by a scanning electron microscopy and evaluated according to a specified score. Assessment of the endothelium was carried out by evaluating the condition of microvilli, cell borders, cell surface and cell pattern. The findings were compared to untreated corneas and those injected with 50 µl of balanced salt solution (BSS).

RESULTS

The corneal endothelium exposed to the antiangiogenic substances showed only minor changes in comparison to the controls treated only with BSS. Also seen during this research was the irreversible cell damage in the control group using triamcinolone.

CONCLUSION

Ranibizumab and bevacizumab have no damaging effects on the corneal endothelium when used in the anterior chamber. They can be administered as an intracameral injection for the treatment of rubeotic secondary glaucoma. Triamcinolon containing benzyl alcohol causes severe damage to the endothelial cells of the cornea by direct contact.

TAM receptor tyrosine kinase function and the immunopathology of liver disease

Tyro3, Axl, MERTK (TAM) receptor tyrosine kinases are implicated in the regulation of the innate immune response through clearance of apoptotic cellular debris and control of cytokine signaling cascades. As a result they are pivotal in regulating the inflammatory response to tissue injury. Within the liver, immune regulatory signaling is employed to prevent the overactivation of innate immunity in response to continual antigenic challenge from the gastrointestinal tract. In this review we appraise current understanding of the role of TAM receptor function in the regulation of both innate and adaptive immunity, with a focus on its impact upon hepatic inflammatory pathology.

Zur Isomerie von Tetrazoliumsalzen II

Durch systematische Untersuchung von Tetrazoliumsalzen mit verschiedenem Anion wie auch verschiedenem Substituenten am C-Arylrest konnte nachgewiesen werden, daß Tetrazoliumsalze generell in verschiedenen Stereoisomeren erhalten werden können.

Eine Modellvorstellung über die durch den C-Arylsubstituenten induzierten Veränderungen in der Elektronendichte-Verteilung des heterozyklischen Systems führte dabei zu einer vernünftig erscheinenden Interpretation der beobachteten Phänomene.

Frequency of symptomatic zinc deficiency in very low birth weight infants

Current concepts on zinc requirements for premature infants rely on studies dating back more than 20 years. Given that nowadays more premature infants frequently survive we aimed to obtain recent frequency data on zinc deficiency in very low birth weight (VLBW) infants.226 VLBW infants born between July 2005 and December 2009 were retrospectively included in this study. Mean gestational age (GA) was 28.7 weeks (range 23+0 to 38+0) and mean birth weight 1120g (range 354-1495). All infants received zinc supplementation according to the ESPGHAN guidelines. 26 (11.5%) patients showed clinical signs for zinc deficiency of whom 15 had serum zinc concentrations < 50µg/dl, 9 between 50 and 70 µg/dl and 2 > 70 µg/dl. Infants presenting with dermatitis had significantly lower concentrations (mean 26.7 µg/dl, range 19-31) when compared to infants with diarrhoea or isolated peripheral oedema (35.3 µg/dl and 51.8 µg/dl respectively). Strongest independent risk factors were low GA, being small for GA and suffering from intestinal resection due to necrotizing enterocolitis. Frequency of zinc concentrations <50 µg/dl were calculated to be 6.6% in VLBW infants.Even though current guidelines for zinc supplementation were followed the frequency of zinc deficiency was found to be unexpectedly high in ELBW and SGA infants. Despite the retrospective nature of this single centre study, our data strongly suggest that recommendations on zinc supplementation in ELBW and SGA infants should be reviewed.