CRISPR (clustered regularly interspaced short palindromic repeat)-Cas (CRISPR-associated protein) systems are diverse and found in many archaea and bacteria. These systems have mainly been ...characterized as adaptive immune systems able to protect against invading mobile genetic elements, including viruses. The first step in this protection is acquisition of spacer sequences from the invader DNA and incorporation of those sequences into the CRISPR array, termed CRISPR adaptation. Progress in understanding the mechanisms and requirements of CRISPR adaptation has largely been accomplished using overexpression of cas genes or plasmid loss assays; little work has focused on endogenous CRISPR-acquired immunity from viral predation. Here, we developed a new biofilm-based assay system to enrich for Pseudomonas aeruginosa strains with new spacer acquisition. We used this assay to demonstrate that P. aeruginosa rapidly acquires spacers protective against DMS3vir, an engineered lytic variant of the Mu-like bacteriophage DMS3, through primed CRISPR adaptation from spacers present in the native CRISPR2 array. We found that for the P. aeruginosa type I-F system, the cas1 gene is required for CRISPR adaptation, recG contributes to (but is not required for) primed CRISPR adaptation, recD is dispensable for primed CRISPR adaptation, and finally, the ability of a putative priming spacer to prime can vary considerably depending on the specific sequences of the spacer.
Our understanding of CRISPR adaptation has expanded largely through experiments in type I CRISPR systems using plasmid loss assays, mutants of Escherichia coli, or cas1-cas2 overexpression systems, but there has been little focus on studying the adaptation of endogenous systems protecting against a lytic bacteriophage. Here we describe a biofilm system that allows P. aeruginosa to rapidly gain spacers protective against a lytic bacteriophage. This approach has allowed us to probe the requirements for CRISPR adaptation in the endogenous type I-F system of P. aeruginosa Our data suggest that CRISPR-acquired immunity in a biofilm may be one reason that many P. aeruginosa strains maintain a CRISPR-Cas system.
Patients from low socioeconomic backgrounds have greater rates of morbidity and mortality across disease processes. The Distressed Communities Index identified several socioeconomic components that ...were used to create a Distressed Communities Index score for every ZIP code, then broken into quintiles from prosperous to distressed. We aimed to explore whether socioeconomic distress as defined by the Distressed Communities Index affects the outcome of complex ventral hernia repair in the elderly population.
Retrospective analysis was performed using the Abdominal Core Health Collaborative data. Included were adults aged 65+ years undergoing elective complex ventral hernia repair from 2013 to 2021. Primary outcomes were postoperative outcomes and composite hernia recurrence by Distressed Communities Index quintile. The Cox proportional hazards model was used for composite recurrence, and logistic regression was used for postoperative outcomes.
A total of 4,172 patients were included. Patients in distressed communities were more likely to identify as female or racial minority and had greater body mass index and American Society of Anesthesiologists class. Lower Distressed Communities Index quintile was associated with larger hernia (P = .012), open repair (P = .019), and 30-day complication (P = .05). There was no association between time to recurrence and Distressed Communities Index quintile (P = .24). After adjusted analysis, there was no significant difference for readmission, reoperation, recurrence, and complications.
Patients from more distressed communities presented in worse clinical status with larger hernias. This likely contributed to greater rates of open repair and complications. However, when adjusted for these variables, outcomes were similar across Distressed Communities Index quintile. This supports the efficacy of complex hernia repair across socioeconomic classes.
The association of frailty on postoperative outcomes after elective and emergency general surgery procedures has been widely studied. However, this association has not been examined in the geriatric ...population stratified by emergency general surgery procedural risk.
A retrospective cohort study was performed using the 2012 to 2017 American College of Surgeons-National Surgical Quality Improvement Program database. We identified geriatric patients (age ≥65 years) undergoing an emergency general surgery procedure within 48 hours of admission stratified by the procedural risk. Frailty was accessed using Modified 5-item Frailty Index, and the patients were divided into 4 groups Modified 5-item Frailty Index = 0, 1, 2, and ≥3. Multivariable logistic regression was used to assess the impact of increasing Modified 5-item Frailty Index score on postoperative complications, failure-to-rescue, and readmissions.
In the study, 16,911 low risk procedure emergency general surgery patients were grouped as (33.3%) Modified 5-item Frailty Index = 0, (45.1%) Modified 5-item Frailty Index = 1, (18.7%) Modified 5-item Frailty Index = 2, and (2.9%) Modified 5-item Frailty Index ≥3 respectively. After multivariable analyses, increasing Modified 5-item Frailty Index score (versus Modified 5-item Frailty Index = 0) was associated with complications (odds ratio 95% confidence interval; Modified 5-item Frailty Index = 2: 2.1 1.3-3.5, Modified 5-item Frailty Index ≥ 3: 2.2 1.2-4.2), failure-to-rescue (Modified 5-item Frailty Index = 2: 2.3 1.3-4.0, Modified 5-item Frailty Index ≥ 3: 2.3 1.2-4.6), readmission (Modified 5-item Frailty Index = 2: 1.4 1.2-1.7, Modified 5-item Frailty Index ≥ 3: 1.5 1.1-2.1). In addition, 30,305 high-risk patients undergoing procedure emergency general surgery were grouped as (24.1%) Modified 5-item Frailty Index = 0, (44.9%) Modified 5-item Frailty Index = 1, (24.0%) Modified 5-item Frailty Index = 2, and (7.0%) Modified 5-item Frailty Index ≥3, respectively. After multivariable analyses, increasing Modified 5-item Frailty Index score (versus Modified 5-item Frailty Index = 0) was associated with complications (odds ratio 95% confidence interval; Modified 5-item Frailty Index = 2: 1.2 1.2–1.3, Modified 5-item Frailty Index ≥3: 1.7 1.5–2.0), failure-to-rescue (Modified 5-item Frailty Index = 2: 1.3 1.2–1.5, Modified 5-item Frailty Index ≥3: 1.5 1.3–1.7), readmission (Modified 5-item Frailty Index = 2: 1.3 1.2–1.4, Modified 5-item Frailty Index ≥3: 1.6 1.4–1.9).
Increasing levels of frailty in geriatric emergency general surgery patients are associated with higher levels of postoperative complications, failure-to-rescue, and readmission. Clinicians should consider frailty in assessing the risk of even low-risk surgeries in this population.
Elotuzumab is a monoclonal antibody in development for multiple myeloma (MM) that targets CS1, a cell surface glycoprotein expressed on MM cells. In preclinical models, elotuzumab exerts anti-MM ...efficacy via natural killer (NK)-cell-mediated antibody-dependent cellular cytotoxicity (ADCC). CS1 is also expressed at lower levels on NK cells where it acts as an activating receptor. We hypothesized that elotuzumab may have additional mechanisms of action via ligation of CS1 on NK cells that complement ADCC activity. Herein, we show that elotuzumab appears to induce activation of NK cells by binding to NK cell CS1 which promotes cytotoxicity against CS1(+) MM cells but not against autologous CS1(+) NK cells. Elotuzumab may also promote CS1–CS1 interactions between NK cells and CS1(+) target cells to enhance cytotoxicity in a manner independent of ADCC. NK cell activation appears dependent on differential expression of the signaling intermediary EAT-2 which is present in NK cells but absent in primary, human MM cells. Taken together, these data suggest elotuzumab may enhance NK cell function directly and confer anti-MM efficacy by means beyond ADCC alone.
Bioenergy will be one component of a suite of alternatives to fossil fuels. Effective conversion of biomass to energy will require the careful pairing of advanced conversion technologies with biomass ...feedstocks optimized for the purpose. Lignocellulosic biomass can be converted to useful energy products via two distinct pathways: enzymatic or thermochemical conversion. The thermochemical pathways are reviewed and potential biotechnology or breeding targets to improve feedstocks for pyrolysis, gasification, and combustion are identified. Biomass traits influencing the effectiveness of the thermochemical process (cell wall composition, mineral and moisture content) differ from those important for enzymatic conversion and so properties are discussed in the language of biologists (biochemical analysis) as well as that of engineers (proximate and ultimate analysis). We discuss the genetic control, potential environmental influence, and consequences of modification of these traits. Improving feedstocks for thermochemical conversion can be accomplished by the optimization of lignin levels, and the reduction of ash and moisture content. We suggest that ultimate analysis and associated properties such as H:C, O:C, and heating value might be more amenable than traditional biochemical analysis to the high-throughput necessary for the phenotyping of large plant populations. Expanding our knowledge of these biomass traits will play a critical role in the utilization of biomass for energy production globally, and add to our understanding of how plants tailor their composition with their environment.
The minimal clinically important difference (MCID) has emerged as a method for evaluating the clinical significance of these PROs, though it is critical to recognize that these values are not ...necessarily commutable across different study populations.2 Two different methods have been identified in the literature to calculate the MCID: the distribution-based method uses the statistical properties of the study results to calculate the MCID, while the anchor-based method compares a change in patient status against an external criterion.3 The authors of this study determined the MCID of the HerQLes score in patients undergoing elective VHRs to answer the fundamental but deceptively complex question: who really benefits from a hernia operation? 3 point out, use of an ordinal scale with the MCID is problematic in and of itself as it assumes a standard unit of change between each interval in the scale, thereby potentially introducing false positive or negative results. ...while the MCID for this study population was 15.6, this value cannot necessarily be extrapolated to all patient populations given the distribution-based method used by the authors to ascertain this value. Appropriate patient selection for this large cohort is essential not only to avoid non-beneficial operations but can also help surgeons (and patients) avoid taking on the risk of surgery and mesh placement when there may not be any quality of life benefit.
To describe 30-day outcomes including post-operative complications, readmissions, and quality of life score changes for older adults undergoing elective ventral hernia repair with retromuscular mesh ...placement and to compare rates of these outcomes for individuals undergoing robotic versus open approaches.
Over one third of patients presenting for elective ventral hernia repair are over the age of 65 and many have complex surgical histories that warrant intricate hernia repairs. Robotic ventral hernia repairs have gained increasing popularity in the US and in some studies have demonstrated decreased rates of postoperative complications, and less pain resulting in shorter hospital stays. However, the robotic approach has several downsides including prolonged operative times as well as the use of pneumo-peritoneum which may be risky in older patients.
We performed a retrospective review of prospectively collected data in a national hernia specific registry (the Abdominal Core Health Quality Collaborative) and identified patients over the age of 65 undergoing either an open or robotic retromuscular ventral hernia repair. After propensity score matching adjusting for demographic, clinical, and hernia related factors, logistic regression was used to compare 30-day complications, readmission, and quality of life (QoL) scores as captured by the HerQLes scale for patients undergoing each approach.
Of 2128 patients who met inclusion criteria, 1695 (79.7%) underwent open ventral hernia repair while 433 (20.3%) underwent robotic repair. After propensity score matching, there were 350 robotic cases and 759 open cases for analysis. Patients undergoing robotic repairs demonstrated significantly shorter length of stays (1 vs 4 days, P < 0.01) and had equivalent odds of both 30-day post-operative complications (odds ratio OR 1.15 95% confidence interval 0.92-1.44) and readmission (OR 1.09 95% confidence interval 0.74-1.6) compared to the open approach. QoL scores were similar between groups at 30 days but were slightly better for robotic patients at 1 year (92 vs 84 P < 0.01).
Robotic ventral hernia repair is an option for appropriately selected older patients undergoing retromuscular ventral hernia repair, demonstrating shorter hospital stays and equivalent rates of complications and readmissions in the post-operative period. However, more data is needed regarding QoL outcomes and long-term function, especially as it relates to recurrence rates, between the two approaches.
Multiple myeloma (MM) patients who receive killer cell Ig–like receptor (KIR) ligand–mismatched, T cell–depleted, allogeneic transplantation may have a reduced risk of relapse compared with patients ...who receive KIR ligand–matched grafts, suggesting the importance of this signaling axis in the natural killer (NK) cell-versus-MM effect. Expanding on this concept, IPH2101 (1-7F9), an anti-inhibitory KIR mAb, enhances NK-cell function against autologous MM cells by blocking the engagement of inhibitory KIR with cognate ligands, promoting immune complex formation and NK-cell cytotoxicity specifically against MM cell targets but not normal cells. IPH2101 prevents negative regulatory signals by inhibitory KIR, whereas lenalidomide augments NK-cell function and also appears to up-regulate ligands for activating NK-cell receptors on MM cells. Lenalidomide and a murine anti-inhibitory NK-cell receptor Ab mediate in vivo rejection of a lenalidomide-resistant tumor. These mechanistic, preclinical data support the use of a combination of IPH2101 and lenalidomide in a phase 2 trial for MM.
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