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Bdellovibrio bacteriovorus is an obligate predator of bacteria ubiquitously found in the environment. Its life cycle is composed of two essential phases: a free-living, non-replicative, fast swimming attack phase (AP) wherein the predator searches for prey; and a non-motile, actively dividing growth phase (GP) in which it consumes the prey. The molecular regulatory mechanisms governing the switch between AP and GP are largely unknown. We used RNA-seq to generate a single-base-resolution map of the Bdellovibrio transcriptome in AP and GP, revealing a specific "AP" transcriptional program, which is largely mutually exclusive of the GP program. Based on the expression map, most genes in the Bdellovibrio genome are classified as "AP only" or "GP only". We experimentally generated a genome-wide map of 140 AP promoters, controlling the majority of AP-specific genes. This revealed a common sigma-like DNA binding site highly similar to the E. coli flagellar genes regulator sigma28 (FliA). Further analyses suggest that FliA has evolved to become a global AP regulator in Bdellovibrio. Our results also reveal a non-coding RNA that is massively expressed in AP. This ncRNA contains a c-di-GMP riboswitch. We suggest it functions as an intracellular reservoir for c-di-GMP, playing a role in the rapid switch from AP to GP.

mRNA levels are determined by the balance between transcription and mRNA degradation, and while transcription has been extensively studied, very little is known regarding the regulation of mRNA degradation and its coordination with transcription. Here we examine the evolution of mRNA degradation rates between two closely related yeast species. Surprisingly, we find that around half of the evolutionary changes in mRNA degradation were coupled to transcriptional changes that exert opposite effects on mRNA levels. Analysis of mRNA degradation rates in an interspecific hybrid further suggests that opposite evolutionary changes in transcription and in mRNA degradation are mechanistically coupled and were generated by the same individual mutations. Coupled changes are associated with divergence of two complexes that were previously implicated both in transcription and in mRNA degradation (Rpb4/7 and Ccr4-Not), as well as with sequence divergence of transcription factor binding motifs. These results suggest that an opposite coupling between the regulation of transcription and that of mRNA degradation has shaped the evolution of gene regulation in yeast.

The affordability of next generation sequencing (NGS) is transforming the field of mutation analysis in bacteria. The genetic basis for phenotype alteration can be identified directly by sequencing the entire genome of the mutant and comparing it to the wild-type (WT) genome, thus identifying acquired mutations. A major limitation for this approach is the need for an a-priori sequenced reference genome for the WT organism, as the short reads of most current NGS approaches usually prohibit de-novo genome assembly. To overcome this limitation we propose a general framework that utilizes the genome of relative organisms as mediators for comparing WT and mutant bacteria. Under this framework, both mutant and WT genomes are sequenced with NGS, and the short sequencing reads are mapped to the mediator genome. Variations between the mutant and the mediator that recur in the WT are ignored, thus pinpointing the differences between the mutant and the WT. To validate this approach we sequenced the genome of Bdellovibrio bacteriovorus 109J, an obligatory bacterial predator, and its prey-independent mutant, and compared both to the mediator species Bdellovibrio bacteriovorus HD100. Although the mutant and the mediator sequences differed in more than 28,000 nucleotide positions, our approach enabled pinpointing the single causative mutation. Experimental validation in 53 additional mutants further established the implicated gene. Our approach extends the applicability of NGS-based mutant analyses beyond the domain of available reference genomes.

Background: Cardiopulmonary resuscitation (CPR) is an emergency procedure performed to restore heart function to minimize anoxic injury to the brain following cardiac arrest. Despite the establishment of emergency department and training on Pediatric Advanced Life Support (PALS) at Muhimbili National Hospital (MNH) the outcomes of pediatric in-hospital cardiac arrest have not been documented. We ought to determine the outcomes and factors associated with 24-h survival after pediatric in-hospital cardiac arrests at MNH in Tanzania., Methods: We conducted a retrospective study of all patients aged 1 month to 18 years who had in-hospital cardiac arrests (IHCA) prompting CPR in the Emergency Medicine Department (EMD) at MNH, Tanzania from January 2016 to December 2019. Data was collected from electronic medical record (Wellsoft) system using a standardized and pretested data collection form that recorded clinical baseline, pre-arrest, arrest, and post-arrest parameters. Bivariate and multivariable logistic regression analyses were performed to assess the influence of each factor on 24-h survival., Results: A total of 11,951 critically ill patients were screened, and 257 (2.1%) had cardiac arrest at EMD. Among 136 patients enrolled, the median age was 1.5 years (interquartile range: 0.5-3 years) years, and the majority 108 (79.4%) aged ≤ 5 years, and 101 (74.3%) had been referred from peripheral hospitals. Overall stained return of spontaneous circulation was achieved in 70 (51.5%) patients, 24-h survival was attained in 43 (31.3%) of patients, and only 7 patients (5.2%) survived to hospital discharge. Factors independently associated with 24-h survival were CPR event during the day/evening (p = 0.033), duration of CPR ≤ 20 min (p = 0.000), reversible causes of cardiac arrest being identified (p = 0.001), and having assisted/mechanical ventilation after CPR (p = 0.002)., Conclusion: In our cohort of children with cardiac arrest, survival to hospital discharge was only 5%. Factors associated with 24-h survival were CPR events during the daytime, short duration of CPR, recognition of reversible causes of cardiac arrest, and receiving mechanical ventilation. Future studies should explore the detection of decompensation, the quality of CPR, and post-cardiac arrest care on the outcomes of IHCA., (© 2024. The Author(s).)

In 2019, 80% of the 7.4 million global child deaths occurred in low- and middle-income countries (LMICs). Global and regional estimates of cause of hospital death and admission in LMIC children are needed to guide global and local priority setting and resource allocation but are currently lacking. The study objective was to estimate global and regional prevalence for common causes of pediatric hospital mortality and admission in LMICs. We performed a systematic review and meta-analysis to identify LMIC observational studies published January 1, 2005-February 26, 2021. Eligible studies included: a general pediatric admission population, a cause of admission or death, and total admissions. We excluded studies with data before 2,000 or without a full text. Two authors independently screened and extracted data. We performed methodological assessment using domains adapted from the Quality in Prognosis Studies tool. Data were pooled using random-effects models where possible. We reported prevalence as a proportion of cause of death or admission per 1,000 admissions with 95% confidence intervals (95% CI). Our search identified 29,637 texts. After duplicate removal and screening, we analyzed 253 studies representing 21.8 million pediatric hospitalizations in 59 LMICs. All-cause pediatric hospital mortality was 4.1% [95% CI 3.4%-4.7%]. The most common causes of mortality (deaths/1,000 admissions) were infectious [12 (95% CI 9-14)]; respiratory [9 (95% CI 5-13)]; and gastrointestinal [9 (95% CI 6-11)]. Common causes of admission (cases/1,000 admissions) were respiratory [255 (95% CI 231-280)]; infectious [214 (95% CI 193-234)]; and gastrointestinal [166 (95% CI 143-190)]. We observed regional variation in estimates. Pediatric hospital mortality remains high in LMICs. Global child health efforts must include measures to reduce hospital mortality including basic emergency and critical care services tailored to the local disease burden. Resources are urgently needed to promote equity in child health research, support researchers, and collect high-quality data in LMICs to further guide priority setting and resource allocation., Competing Interests: JC-C speaker for Novamed and Tecnoquimicas; received financial travel support from BAGO to attend the Colombian Congress of Pediatrics; participated in an Advisory Board for ZambonColombia; acted as an investigator in phase 2 and 3 clinical trials of Merck Sharp and Dhome drugs (antibiotics and monoclonal antibodies) that do not interfere in the course of this study. JL stock options in MERCK and MODERNA. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor “CFO” declared a past co-authorship with the authors “NK & MOW”. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (© 2024 Kortz, Mediratta, Smith, Nielsen, Agulnik, Gordon Rivera, Reeves, O’Brien, Lee, Abbas, Attebery, Bacha, Bhutta, Biewen, Camacho-Cruz, Coronado Muñoz, deAlmeida, Domeryo Owusu, Fonseca, Hooli, Wynkoop, Leimanis-Laurens, Nicholaus Mally, McCarthy, Mutekanga, Pineda, Remy, Sanders, Tabor, Teixeira Rodrigues, Yuee Wang, Kissoon, Takwoingi, Wiens and Bhutta.)

Objectives: Ileal conduits (ICs) carry an additional perioperative complication risk due to the bowel procedure. This analysis compares surgical outcomes in patients ≥75 years of age with ureterocutaneostomy (UCN) and IC after cystectomy (Cx)., Methods: Data of 527 patients included in a retrospective cystectomy database of two high volume centers (2008-2020) were queried to identify elderly patients (≥75 years) who underwent Cx either with IC or UCN. Patient characteristics of all patients [age, BMI, Charlson Comorbidity Index (CCI)], perioperative parameters (operation time, blood loss, transfusions, tumor stage), and postoperative complications (clavien >IIIA, intensive care unit (ICU) stay) were compared. As special focus, bowel complications requiring surgical revision (rBCs) were analyzed. In patients with IC, the rate of ureteral implantation stenosis (USt) was recorded. As a population of special interest, patients ≥80 years of age were analyzed separately. Categorical data were compared using Fisher exact test, and continuous data were compared using Mann-Whitney U test., Results: A total of 163 patients ≥75 years of age (125 IC, 38 UCN) were identified. Patients with UCN were older and presented with a higher CCI, though differences were not statistically different. Surgery with palliative intent was more frequent in patients with UCN (37 vs. 10%). Operation time in UCN was significantly shorter (233 vs. 305 min, p = 0.02), while blood loss and transfusion rate were comparable. Overall complication rate (Clavien-Dindo grade IIIA-IVB) was comparable (UCN 34% vs. IC 37%). However, rBC was a rare complication in UCN (3/38) as compared to patients with IC (15/125). Frequency of postoperative ICU stay (UCN 16% vs. IC 16%) and 90-day mortality did not differ (UCN 3/38 patients, IC 5/125 patients). Regarding long-term follow-up, USt requiring revision or permanent stenting was seen in 18/125 (14%) patients with IC. In patients >80 years of age, results were comparable to the main cohort. Low event rate regarding complications and bias inherent of a retrospective analysis (selection bias, unequal distribution in case numbers) precludes detection of statistical differences regarding patients' characteristics and overall complication rate., Conclusion: UCN is an alternative to IC in elderly and/or frail patients. Severe bowel complications are numerically less frequent and operation time is minimized., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mally, John, Pfister, Heidenreich, Albers and Niegisch.)

Robot-assisted surgery in urology is now being used in a wide range of procedures. In addition to reconstructive procedures, tumour surgery such as radical cystectomy is of particular importance. While studies on the perioperative quality of robotic-assisted radical cystectomy suggest a favorable impact on morbidity (and thus mortality), the question remains as to what extent the oncological quality is influenced by this procedure in terms of recurrence-free and overall survival.In this context, following a comprehensive literature review, this paper presents data from retrospective cohort comparisons of open and robotic cystectomy, registry data and single centre series on robotic and open cystectomy, and the results of prospective randomised trials.In summary, from an oncological point of view, robotic cystectomy is not inferior to open cystectomy. Overall survival, cancer-specific survival, and progression-free survival data do not differ in retrospective cohort studies, in indirect comparisons of registry data and/or large series, or in prospective studies to date. With regard to the occurrence of atypical metastases after robotic cystectomy, prospective data are currently lacking and retrospective analysis produce conflicting data. However, general oncological outcome seems not to be affected.Thus, robotic-assisted cystectomy is also from an oncological point of view a good option for patients who have an indication for radical cystectomy., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Transurethral resection of bladder cancer is a standard procedure in urology which requires complete resection. Knowledge of the possible complications and their management is essential for practicing urologists. The most common complications are catheter related bladder symptoms, bleeding, infections and perforation of the bladder. Resection of the orifice and positional damage are seldom but severe complications which need immediate treatment. In this review, we summarise the above mentioned complications as well as their management., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Data on oncological follow-up after robotic-assisted radical cystectomy (RARC) have been reported only scarcely and individual studies have reported an increase in early recurrences and atypical recurrences., Patients and Methods: Clinical data of 89 patients with RARC were compared to 59 patients with open radical cystectomy (ORC) at a single institution. Two-year cancer-specific (2y-CSS) and 2-year overall survival (2y-OS) related to histopathological tumor stage of RARC patients calculated by Kaplan-Meier method were compared to ORC patients using log-rank test. Early clinical recurrence rate (eCR, progression ≤6 months post-cystectomy) and metastatic pattern of both groups were compared by chi-square test., Results: Median follow-up 32 months (RARC) and 47.5 months (ORC), both groups were balanced in baseline characteristics. For RARC pts, -2y-OS and CSS-free survival rates were 80 and 90%, for ORC pts 65 and 71% (all p > 0.05). Margin status was not significantly different. eCR was observed in 10 out of 89 (11%) RARC pts and in 7 out of 59 (12%) ORC pts (p = 0.9). No difference in atypical metastases was seen between groups., Conclusion: Two-year oncological outcomes of RARC patients are comparable to ORC patients without differences regarding ePR or metastatic pattern., (© 2018 S. Karger AG, Basel.)

Background: Mitochondrial large-conductance Ca2+-sensitive potassium (mBKCa) channels are involved in myocardial ischemic preconditioning. Their role in sildenafil-induced cardioprotection is unknown. We investigated whether sildenafil-induced acute cardioprotection is mediated by activation of mBKCa channels in the rat heart in vitro., Methods: Male Wistar rats (n = 8 per group) were randomized and anesthetized with pentobarbital (90 mg/kg). Hearts were isolated, mounted on a Langendorff system and perfused with Krebs-Henseleit buffer at a constant pressure of 80 mmHg. Hearts underwent 30 min of global ischemia followed by 60 min of reperfusion. At the end of the experiments infarct size was determined by TTC staining. In the control group rats were not further treated. Sildenafil (3 μM) was administered over 10 min before the beginning of ischemia. The mBKCa channel inhibitor paxilline (1 μM) was administered with and without sildenafil before the onset of ischemia. The pathway underlying sildenafil-induced cardioprotection was further investigated with the protein kinase G blocker KT5823 (1 μM). Myocardial cGMP concentration was measured by ELISA. Data (mean±SD) were analysed with a one and two-way analysis of variance as appropriate., Results: In control animals infarct size was 52±8%. Sildenafil increased cGMP concentration and reduced infarct size to 35±6% (P<0.05 vs. control). Paxilline and KT5823 completely blocked sildenafil-induced cardioprotection (paxilline+sildenafil: 50±8%, KT5823+sildenafil: 45±8%; both P<0.05 vs. sildenafil). Functional heart parameters and coronary flow were not different between the study groups., Conclusion: This study shows that in male rats protein kinase G-dependent opening of mBKCa channels plays a pivotal role in sildenafil-induced cardioprotection.

Purpose: We studied the possibility that age, height, weight and body mass index could be used to predict the likelihood of successful ureteroscopic access to the upper urinary tract without previous stent placement in prepubertal children., Materials and Methods: We retrospectively reviewed all ureteroscopic procedures for upper tract calculi in prepubertal children from 2003 to 2007. We compared age, height, weight and body mass index in patients who underwent successful primary flexible ureteroscopic access and in those who required initial stent placement to perform ureteroscopy., Results: Successful primary ureteroscopic access to the upper tract was achieved in 18 of 30 patients (60%). There was no difference in mean age (9.9 vs 9.5 years, p = 0.8), height (132 vs 128 cm, p = 0.6), weight (37 vs 36 kg, p = 0.86) or body mass index (19.3 vs 20.5 kg/m(2), p = 0.55) between patients with successful vs unsuccessful upper tract access. Locations that prevented access to the upper urinary tract were evenly distributed among the ureteral orifice, iliac vessels and ureteropelvic junction., Conclusions: Age, height, weight and body mass index could not predict the likelihood of successful ureteroscopic access to the upper tract. Placement of a ureteral stent for passive ureteral dilation is not necessary for successful ureteroscopic access to the renal pelvis in prepubertal children. An initial attempt at ureteroscopy, with placement of a ureteral stent if upper tract access is unsuccessful, decreases the number of procedures while maintaining a low complication rate.