Clinical relevance of the 3-cm threshold in sigmoid diverticulitis with abscess: consensus or quandary?

PURPOSE: Diverticular abscess is a common manifestation of acute complicated diverticulitis. We aimed to analyze the clinical course of patients with diverticular abscess initially treated conservatively. METHODS: All patients with diverticular abscess undergoing elective or urgent/emergency surgery from October 2004 to October 2022 were identified from our institutional database. Depending on the abscess size, patients were divided into group A (≤ 3 cm) and group B (> 3 cm). Conservative treatment failure was defined as clinical deterioration, persistent or recurrent abscess, or urgent/emergency surgery. Baseline characteristics and short-term perioperative outcomes were recorded and compared between both groups. Uni- and multivariate analyses were conducted to identify determinants of conservative treatment failure and overall ostomy formation. RESULTS: A total of 105 patients were enrolled into group A (n = 73) and group B (n = 32). Uni- and multivariate analyses revealed abscess size as the only significant factor of conservative therapy failure [OR 9.904; p < 0.0001], while overall ostomy formation was significantly affected by an increased body mass index (BMI) [OR 1.366; p = 0.026]. There were no significant differences in perioperative outcome with the exception of a longer total hospital stay in patients managed with abscess drainage compared to antibiotics alone prior surgery in group B (p = 0.045). CONCLUSION: Abscess diameter > 3 cm is not just an arbitrary chosen cut-off value for drainage placement but has a prognostic impact on medical treatment failure in patients with complicated acute diverticulitis. In this subgroup, the choice between primary drainage and antibiotics does not appear to influence outcome at the cost of prolonged hospital stay after drainage insertion.

Caffeine intake enhances bowel recovery after colorectal surgery: a meta-analysis of randomized and non-randomized studies.

Postoperative ileus (POI) after colorectal surgery is a major problem that affects both patient recovery and hospital costs highlighting the importance of preventive strategies. Therefore, we aimed to perform a systematic analysis of the effects of postoperative caffeine consumption on bowel recovery and surgical morbidity after colorectal surgery. A comprehensive literature search was conducted through September 2023 for randomized and non-randomized trials comparing the effect of caffeinated versus non-caffeinated drinks on POI by evaluating bowel movement resumption, time to first flatus and solid food intake, and length of hospital stay (LOS). Secondary outcome analysis included postoperative morbidity in both groups. After data extraction and inclusion in a meta-analysis, odds ratios (ORs) for dichotomous variables and standardized mean differences (SMDs) for continuous outcomes with 95% confidence intervals (CIs) were calculated. Subgroup analyses were performed in cases of substantial heterogeneity. Six randomized and two non-randomized trials with a total of 610 patients were included in the meta-analysis. Caffeine intake significantly reduced time to first bowel movement [SMD -0.39, (95% CI -0.66 to -0.12), p = 0.005] and time to first solid food intake [SMD -0.41, (95% CI -0.79 to -0.04), p = 0.03] in elective laparoscopic colorectal surgery, while time to first flatus, LOS, and the secondary outcomes did not differ significantly. Postoperative caffeine consumption may be a reasonable strategy to prevent POI after elective colorectal surgery. However, larger randomized controlled trials (RCTs) with homogeneous study protocols, especially regarding the dosage form of caffeine and coffee, are needed.

Routine closed-suction drainage reduces seromas following totally extraperitoneal (TEP) inguinal hernia repair: A meta-analysis.

BACKGROUND: The value of prophylactic closed-suction drainage in totally extraperitoneal inguinal hernia repair (TEP) is still a matter of controversy. We conducted a meta-analysis of studies examining postoperative seroma rates in patients with or without routine placement of closed-suction drainage tubes. METHODS: A systematic literature search was conducted for trials comparing the outcome of TEP with or without routine drainage placement. Data regarding postoperative outcomes were extracted and compared by meta-analysis. The odds ratio and standardized mean differences with 95% confidence intervals were calculated. RESULTS: Four studies were identified, involving a total of 1626 cases (Drain: n = 1251, no Drain: n = 375). There was a statistically significant difference noted between the 2 groups regarding postoperative seroma formation favoring the Drain group (odds ratio = 0.12; 95% confidence intervals [0.05, 0.29]; P < .001; 4 studies; I2 = 72%). For the remaining secondary endpoints postoperative urinary retention, recurrence, mesh infection and in-hospital length of stay no statistically significant difference was noted between the 2 study groups. CONCLUSION: Current evidence suggests that patients who underwent TEP with routine closed-suction drain placement developed significantly fewer seromas without any additional morbidity or prolongation of in-hospital stay.

A Revised Version of the TNM Classification Leads to Optimized Predictive Performance in Patients with Adrenocortical Carcinoma.

The prognostic stratification of the current AJCC/UICC TNM classification for adrenocortical carcinoma (ACC) has been validated in only a few studies. In this study, it was hypothesized that redefining the T category cut-off would result in a significant improvement in estimated stage-related survival. In 935 patients with ACC from the SEER database, optimal cut-off values based on tumor size were first determined to redefine T1 and T2 categories. Cox proportional hazards regression analysis and receiver operating characteristics (ROC) were then used to determine the prognostic value of the revised version. A new cut-off value of 9.5 cm tumor size was established to differentiate between T1 and T2 tumors, leading to a revised TNM classification. As a result, a more homogeneous distribution of patients with ACC across all stages was observed. Notably, the predictive value of the newly proposed TNM classification in the ROC analysis exceeded that of the 7th and 8th editions of the AJCC/UICC classification system. Finally, the prognostic superiority of the revised TNM classification was confirmed in a multivariate Cox proportional hazards regression model. In conclusion, the present study demonstrates that updating the current staging system with revised T1 and T2 categories significantly improves the prediction of cancer-specific survival (CSS) in patients with ACC.

AI-based prevention of interval cancers in a national mammography screening program.

PURPOSE: To demonstrate that artificial intelligence (AI) can detect and correctly localise retrospectively visible cancers that were missed and diagnosed as interval cancers (false negative (FN) and minimal signs (MS) interval cancers), and to characterise AI performance on non-visible occult and true interval cancers. METHOD: Prior screening mammograms from N = 2,396 women diagnosed with interval breast cancer between March 2006 and May 2018 in north-western Germany were analysed with an AI system, producing a model score for all studies. All included studies previously underwent independent radiological review at a mammography reference centre to confirm interval cancer classification. Model score distributions were visualised with histograms. We computed the proportion and accompanying 95% confidence intervals (CI) of retrospectively visible and true interval cancers detected and correctly localised by AI at different operating points representing recall rates < 3%. Clinicopathological characteristics of retrospectively visible cancers detected by AI and not were compared using the Chi-squared test and binary logistic regression. RESULTS: Following radiological review, 15.6% of the interval cancer cases were categorised as FN, 19.5% MS, 11.4% occult, and 53.4% true interval cancers. At an operating point of 99.0% specificity, AI could detect and correctly localise 27.5% (95% CI: 23.3-32.3%), and 12.2% (95% CI: 9.5-15.5%) of the FN and MS cases on the prior mammogram, respectively. 228 of these retrospectively visible cases were advanced/metastatic at diagnosis; 21.1% (95% CI: 16.3-26.8%) were found by AI on the screening mammogram. Increased likelihood of detection of retrospectively visible cancers with AI was observed for lower-grade carcinomas and those with involved lymph nodes at diagnosis. Among true interval cancers, AI could detect and correctly localise in the screening mammogram where subsequent malignancies would appear in 2.8% (95% CI: 2.0-3.9%) of cases. CONCLUSIONS: AI can support radiologists by detecting a greater number of carcinomas, subsequently decreasing the interval cancer rate and the number of advanced and metastatic cancers.

Optimality in COVID-19 vaccination strategies determined by heterogeneity in human-human interaction networks

Reaching population immunity against COVID-19 is proving difficult even in countries with high vaccination levels. We demonstrate that this in part is due to heterogeneity and stochasticity resulting from community-specific human-human interaction and infection networks. We address this challenge by community-specific simulation of adaptive strategies. Analyzing the predicted effect of vaccination into an ongoing COVID-19 outbreak, we find that adaptive combinations of targeted vaccination and non-pharmaceutical interventions (NPIs) are required to reach population immunity. Importantly, the threshold for population immunity is not a unique number but strategy and community dependent. Furthermore, the dynamics of COVID-19 outbreaks is highly community-specific: in some communities vaccinating highly interactive people diminishes the risk for an infection wave, while vaccinating the elderly reduces fatalities when vaccinations are low due to supply or hesitancy. Similarly, while risk groups should be vaccinated first to minimize fatalities, optimality branching is observed with increasing population immunity. Bimodality emerges as the infection network gains complexity over time, which entails that NPIs generally need to be longer and stricter. Thus, we analyze and quantify the requirement for NPIs dependent on the chosen vaccination strategy. We validate our simulation platform on real-world epidemiological data and demonstrate that it can predict pathways to population immunity for diverse communities world-wide challenged by limited vaccination.

West syndrome caused by ST3Gal-III deficiency.

West syndrome consists of infantile spasms, hypsarrhythmia, and developmental arrest. Most patients remain mentally retarded and many develop Lennox-Gastaut syndrome. Using homozygosity mapping followed by exome sequencing we identified an ST3GAL3 mutation in three infants with West syndrome. ST3GAL3 encodes a sialyltransferase involved in the biosynthesis of sialyl-Lewis epitopes on cell surface-expressed glycoproteins. The mutation affected an essential sialyl-motif and abolished enzymatic activity. Abnormalities in proteins involved in forebrain γ-aminobutyric acid (GABA)ergic synaptic growth and function were recently proposed to account for infantile spasms. Dysfunctional ST3GAL3 may thus result in perturbation of the posttranslational sialylation of proteins in these pathways.

Development of a real-time PCR and a sandwich ELISA for detection of potentially allergenic trace amounts of peanut (Arachis hypogaea) in processed foods.

Hidden allergens in food products are, especially for peanut-allergic consumers, a serious problem because even low amounts (approximately 200 microg) of peanut can elicit allergic reactions. Undeclared peanut traces can be found in processed food products, because contaminations with peanut during production processes are frequent. To minimize the risk of such cross-contaminations, it is necessary to develop sensitive analytical methods for the detection of hidden allergens in foods. For this approach we developed two peanut-specific assays based on the detection of peanut protein by specific antibodies (sandwich ELISA) and by the detection of peanut-specific DNA (part of the coding region of Ara h 2) by a real-time PCR. Both tests did not show any cross-reactivity with 22 common food ingredients (cereals, nuts, legumes), and the limit of detection is <10 ppm peanut in processed foods. Thirty-three random samples of food products were tested for the presence of peanut to compare both assay types with each other and to evaluate the percentage of foods on the German market that are contaminated with peanut traces. We found that four products (13.3%) without peanut in the list of ingredients contained peanut protein in a range from 1 to 74 ppm peanut protein and that the results of both tests correlated well. The real-time PCR was able to detect one more positive sample than the sandwich ELISA. In conclusion, both assays are sensitive and specific tools for the detection of hidden allergens in processed foods.

Impact of a disruption of a pathway delivering copper to mitochondria on Podospora anserina metabolism and life span.

A global depletion of cellular copper as the result of a deficiency in high-affinity copper uptake was previously shown to affect the phenotype and life span of the filamentous fungus Podospora anserina. We report here the construction of a strain in which the delivery of copper to complex IV of the mitochondrial respiratory chain is affected. This strain, PaCox17::ble, is a PaCox17-null mutant that does not synthesize the molecular chaperone targeting copper to cytochrome c oxidase subunit II. PaCox17::ble is characterized by a decreased growth rate, a reduction in aerial hyphae formation, reduced female fertility, and a dramatic increase in life span. The mutant respires via a cyanide-resistant alternative pathway, displays superoxide dismutase (SOD) activity profiles significantly differing from those of the wild-type strain and is characterized by a stabilization of the mitochondrial DNA. Collectively, the presented data define individual components of a molecular network effective in life span modulation and copper as an element with a dual effect. As a cofactor of complex IV of the respiratory chain, it is indirectly involved in the generation of reactive oxygen species (ROS) and thereby plays a life span-limiting role. In contrast, Cu/Zn SOD as a ROS-scavenging enzyme lowers molecular damage and thus positively affects life span. Such considerations explain the reported differences in life span of independent mutants and spread more light on the delicate tuning of the molecular network influencing biological ageing.

Protein quantification, sandwich ELISA, and real-time PCR used to monitor industrial cleaning procedures for contamination with peanut and celery allergens.

In the United States, peanut is one of the main sources of food allergens. Similarly, celery is a common allergenic food in Western Europe. Severe allergic reactions to both foods are common. Unexpected allergic reactions can occur after the consumption of celery- and peanut-free foods as a result of inadvertent cross-contaminations during manufacturing. Therefore, in cooperation with a flavor manufacturer, we monitored the cleaning process of slurry preparation equipment with regard to contaminations of follow-up products with celery and peanut compounds. Washing water samples taken after different cleaning steps and follow-up products were analyzed for the presence of celery and peanut traces with a celery-specific real-time polymerase chain reaction (PCR) and a peanut-specific sandwich enzyme-linked immunosorbent assay (ELISA). PCR and ELISA were compared with a nonspecific protein assay to evaluate whether the detection of protein traces can be a fast and cost-effective method for monitoring the effectiveness of wet cleaning procedures. Additionally, the allergenic potential of the celery and peanut mush, which were used as source material, were measured by a mediator release assay using a rat basophilic leukemia (RBL) cell line. In conclusion, the quantification of total protein in washing water was suitable for monitoring the cleaning process. Our study also revealed evidence that, in cases where wet cleaning is applicable, allergenic traces can be removed with high efficiency.

A novel approach for the detection of potentially hazardous pepsin stable hazelnut proteins as contaminants in chocolate-based food.

Contamination of food products with pepsin resistant allergens is generally believed to be a serious threat to patients with severe food allergy. A sandwich type enzyme-linked immunosorbent assay (ELISA) was developed to measure pepsin resistant hazelnut protein in food products. Capturing and detecting rabbit antibodies were raised against pepsin-digested hazelnut and untreated hazelnut protein, respectively. The assay showed a detection limit of 0.7 ng/mL hazelnut protein or <1 microg hazelnut in 1 g food matrix and a maximum of 0.034% cross-reactivity (peanut). Chocolate samples spiked with 0.5-100 microg hazelnut/g chocolate showed a mean recovery of 97.3%. In 9/12 food products labeled "may contain nuts", hazelnut was detected between 1.2 and 417 microg hazelnut/g food. It can be concluded that the application of antibodies directed to pepsin-digested food extracts in ELISA can facilitate specific detection of stable proteins that have the highest potential of inducing severe food anaphylaxis.

Neutralizing antibodies against conserved domains of p15E of porcine endogenous retroviruses: basis for a vaccine for xenotransplantation?

Porcine xenotransplants may offer a potential solution to the problem posed by the limited supply of allotransplants. However, xenotransplantation may be associated with the risk of transmission of microorganisms, in particular of porcine endogenous retroviruses (PERVs) that are an integral part of the porcine genome and able to infect human cells in vitro. Possible strategies to prevent virus transmission include the development of PERV knockout animals or of effective vaccines. When antisera prepared against the main structural proteins of PERV were screened, a goat antiserum against the recombinant ectodomain of the transmembrane envelope protein p15E was found to neutralize PERV infectivity. Epitope mapping using overlapping peptides revealed two epitopes, E1 (GPQQLEK) and E2 (FEGWFN). These sequences are identical for all PERVs and are highly conserved among all gammaretroviruses. Interestingly, antibodies isolated from AIDS patients and specific for sequences of HIV-1 partially homologous with E2 (Mab4E10, LWNWFN) or located in close proximity to E2 (Mab2F5, ELDKWA) are known to neutralize several strains of HIV-1. It is the first report showing epitope mapping of gammaretrovirus-specific neutralizing antibodies and demonstrating similarity to corresponding epitopes in HIV. These domains of the transmembrane proteins of different retroviruses are an effective target for neutralizing antibodies and may be a useful antigen to create an antiretroviral vaccine.

Detection of potentially allergenic hazelnut (Corylus avellana) residues in food: a comparative study with DNA PCR-ELISA and protein sandwich-ELISA.

Allergen detection is of increasing interest for food labeling purposes. A comparative study with a commercial hazelnut-specific PCR-ELISA and a sandwich-type ELISA detecting hazelnut protein was performed to investigate to what extent immunochemical and DNA-based techniques would correlate in the detection of trace amounts of potentially allergenic hazelnut residues. Both methods were highly sensitive and allowed the detection of even <10 ppm of hazelnut in complex food matrixes. The protein-ELISA was highly specific for hazelnut. However, some foods could lead to false-positive results at the 10 ppm level. The PCR-ELISA did not show any cross-reactions with non-hazelnut foods, thus reducing the probability of having false positives at the trace level. Forty-one commercial food products with and without hazelnut components on their labels were analyzed for the presence of hazelnut. Of the 27 products in which hazelnut components were detected, two samples were not identified by the protein-ELISA, and only one sample, namely one white chocolate having <1 ppm of hazelnut protein, was not detected by PCR-ELISA. The good correlation of the results of PCR-ELISA and protein-ELISA suggested that both PCR-based and immunochemical techniques are suitable for reliable detection of potentially allergenic hazelnut residues in foods at the trace level.

Copper homeostasis and aging in the fungal model system Podospora anserina: differential expression of PaCtr3 encoding a copper transporter.

Lifespan extension of Podospora anserina mutant grisea is caused by a loss-of-function mutation in the nuclear gene Grisea. This gene encodes the copper regulated transcription factor GRISEA recently shown to be involved in the expression of PaSod2 encoding the mitochondrial manganese superoxide dismutase. Here we report the identification and characterization of a second target gene. This gene, PaCtr3, encodes a functional homologue of the Saccharomyces cerevisiae high affinity copper permease yCTR3. PaCtr3 is not expressed in the grisea mutant confirming the assumption that the extension of lifespan is primarily caused by cellular copper limitation and a switch from a cytochrome oxidase (COX)-dependent to and alternative oxidase (AOX)-dependent respiration. Transcript levels of PaCtr3 and PaSod2 respond to copper, iron, manganese and zinc. Transcription of PaCtr3 was found to be down-regulated during senescence of wild-type cultures suggesting that the intracellular copper concentration is raised in old cultures. A two hybrid analysis suggested that GRISEA acts as a homodimer. In accordance, an inverted repeat was identified as a putative binding sequence in the promoter region of PaCtr3 and of PaSod2. Finally, the expression of PaCtr3 in transformants of the grisea mutant led to lifespan shortening. This effect correlates with the activity of the copper-dependent COX demonstrating a strong link between copper-uptake, respiration and lifespan.