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The production of antimicrobial peptides/proteins (AMPs) in sufficient quantities for clinical evaluation is challenging because complex peptides are unsuitable for chemical synthesis, natural sources have low yields, and heterologous systems often have low expression levels or require product-specific process adaptations. Here we describe the production of a complex AMP, the insect metalloproteinase inhibitor (IMPI), by adding a C-terminal C-tag to increase the yield compared to the unmodified peptide. We used a design of experiments approach for process intensification in Escherichia coli Rosetta-gami 2(DE3)pLysS cells and achieved a yield of 260 mg L -1 , which is up to 30-fold higher than previously reported. The C-tag also enhanced product purity but had no effect on IMPI activity, making tag removal unnecessary and therefore simplifying process analytics and downstream processing. We have confirmed that the C-tag is compatible with the peptide and could form the basis of a platform technology for the expression, purification and detection of diverse AMPs produced in E. coli., (Copyright © 2023 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Antimicrobial peptides and proteins (AMPs) are promising alternatives to conventional antibiotics for the treatment of infections caused by multidrug-resistant bacteria. The production of recombinant AMPs is facilitated by platform technologies such as the C-tag, a sequence of four C-terminal amino acids that allows immunoaffinity capture and purification. However, the detection and quantification of such products throughout the manufacturing process is a significant challenge. We therefore used a design of experiments approach to optimize a novel high-throughput analytical immunoaffinity chromatography method for the accurate quantification of AMPs containing a C-tag, resulting in minimal analyte carryover (98.8 ± 0.1 % product elution). We then validated the method in accordance with International Conference on Harmonisation guideline Q2(R2). Validation confirmed that the method achieves high specificity, linearity, accuracy, and precision. We implemented in-process control and quantification throughout the manufacturing process, from cell lysis to the final purified product. We found that the lysate and acidic samples (pH < 2) can lead to deviations. However, following sample pretreatment, C-tag quantification reduced the error to ≤ 4 %, which is potentially superior to current non-specific quantification methods such as UV absorbance and colorimetry. Implementing this method for in-process control and quantification throughout the manufacturing process achieves the reliable assessment of product quantity and quality. This method also offers improvements over the product-specific enzyme-linked immunosorbent assay currently used for C-tagged products because it has a higher precision, accuracy and throughput, with a measurement time of 2.5 min per sample. Our analytical affinity chromatography method is therefore a valuable tool for the quantification of AMPs as part of a novel platform technology approach for C-tagged products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background and Objectives: The aims of this multi-institutional study were to assess the feasibility of iterative cytoreductive surgery (iCRS)/hyperthermic intraperitoneal chemotherapy, iCRS in colorectal peritoneal carcinomatosis (CRPC), evaluate survival, recurrence, morbidity and mortality outcomes, and identify prognostic factors for overall survival., Methods: Patients with CRPC that underwent an iCRS, with or without intraperitoneal chemotherapy, from June 1993 to July 2016 at 13 institutions were retrospectively analyzed from prospectively maintained databases., Results: The study comprised of 231 patients, including 126 females (54.5%) with a mean age at iCRS of 51.3 years. The iterative high-grade (3/4) morbidity and mortality rates were 23.4% and 1.7%, respectively. The median recurrence-free survival was 15.0 and 10.1 months after initial and iCRS, respectively. The median and 5-year survivals were 49.1 months and 43% and 26.4 months and 26% from the initial and iCRS, respectively. Independent negative predictors of survival from the initial CRS included peritoneal carcinomatosis index (PCI) > 20 ( P = 0.02) and lymph node positivity ( P = 0.04), and from iCRS, PCI > 10 ( P = 0.03 for PCI 11-20; P < 0.001 for PCI > 20), high-grade complications ( P = 0.012), and incomplete cytoreduction ( P < 0.001)., Conclusion: iCRS can provide long-term survival benefits to highly selected colorectal peritoneal carcinomatosis patients with comparable mortality and morbidity rates to the initial CRS procedure. Careful patient selection is necessary to improve overall outcomes., (© 2018 Wiley Periodicals, Inc.)

Background: Delirium is increasingly recognized as a common and important postoperative complication that significantly hinders surgical recovery. However, there is a paucity of data examining the incidence and impact of delirium after liver transplantation., Methods: Retrospective case series in a tertiary care center examining all (n = 144) adult patients who underwent liver transplantation during a 6-y period., Results: Delirium occurred in 25% of the patients with an average duration of 4.56 d. Patients who developed delirium were older (P = 0.007), had higher preoperative model for end-stage liver disease score (P = 0.019) and longer pretransplant hospital length of stay (LOS; P = 0.003). Patients with delirium were also more likely to have alcohol ingestion as an etiology of the liver failure (P = 0.033). Delirious patients had a trend toward increased ventilator days (P = 0.235) and significantly longer postoperative hospital (P = 0.001) and intensive care unit LOS (P = 0.001). Delirium was also associated with an increased frequency of hospital acquired infections including urinary tract infections (P = 0.005) and pneumonias (P = 0.001)., Conclusions: Delirium is a common occurrence among liver transplant patients associated with increased complications and LOSs. Further prospective studies are needed to determine the specific risk factors in this complex population and to determine if delirium has an impact on long-term outcomes., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The tuberous sclerosis proteins TSC1 and TSC2 are key integrators of growth factor signaling. They suppress cell growth and proliferation by acting in a heteromeric complex to inhibit the mammalian target of rapamycin complex 1 (mTORC1). In this study, we identify TSC1 as a component of the transforming growth factor β (TGF-β)-Smad2/3 pathway. Here, TSC1 functions independently of TSC2. TSC1 interacts with the TGF-β receptor complex and Smad2/3 and is required for their association with one another. TSC1 regulates TGF-β-induced Smad2/3 phosphorylation and target gene expression and controls TGF-β-induced growth arrest and epithelial-to-mesenchymal transition (EMT). Hyperactive Akt specifically activates TSC1-dependent cytostatic Smad signaling to induce growth arrest. Thus, TSC1 couples Akt activity to TGF-β-Smad2/3 signaling. This has implications for cancer treatments targeting phosphoinositide 3-kinases and Akt because they may impair tumor-suppressive cytostatic TGF-β signaling by inhibiting Akt- and TSC1-dependent Smad activation., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Mammalian target of rapamycin complex 1 (mTORC1) controls growth and survival in response to metabolic cues. Oxidative stress affects mTORC1 via inhibitory and stimulatory inputs. Whereas downregulation of TSC1-TSC2 activates mTORC1 upon oxidative stress, the molecular mechanism of mTORC1 inhibition remains unknown. Here, we identify astrin as an essential negative mTORC1 regulator in the cellular stress response. Upon stress, astrin inhibits mTORC1 association and recruits the mTORC1 component raptor to stress granules (SGs), thereby preventing mTORC1-hyperactivation-induced apoptosis. In turn, balanced mTORC1 activity enables expression of stress factors. By identifying astrin as a direct molecular link between mTORC1, SG assembly, and the stress response, we establish a unifying model of mTORC1 inhibition and activation upon stress. Importantly, we show that in cancer cells, apoptosis suppression during stress depends on astrin. Being frequently upregulated in tumors, astrin is a potential clinically relevant target to sensitize tumors to apoptosis., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Inpatient hyperglycemia has become a major focus at many hospitals. However, although several professional organizations have pushed for improved inpatient glucose management, glycemic control at many institutions remains suboptimal. There is a general consensus that improved quality of care is needed, but objective assessment of care quality remains a challenge. Lack of clear, effective performance feedback to clinicians is one element that may derail efforts to improve practice., Methods: We developed a simplified grading system, the Quality Hyperglycemia Score (QHS), to allow clinicians and managers to easily review and compare glycemic management on adult medical-surgical and intensive care units over the prior 3 months and to more fully engage patient care teams in quality improvement., Results: The QHS represents a single value from 0 to 100, incorporating elements of glycemic management influenced by all team members. The scoring system rewards the maintenance of blood glucose levels in or near the normal range and adherence to the hospital policy on the use of bedside glucose meters, but penalizes frequent hypoglycemic episodes and severe hyperglycemic excursions. Each element is weighted independently and summed to produce the QHS. Scores then correspond to a color code highlighting each unit's performance level., Conclusions: To date, the QHS reflects the spectrum of blood glucose management at our hospital. While refinement and internal and external validation with clinical outcomes are planned, we propose the QHS as a standardized, objective measure of the quality of inpatient glycemic management.

Background: This study assesses if a physicochemical (PC) approach to acid-base balance improves the accuracy of acid-base diagnosis, and reduces inappropriate fluid loading., Methods: Hundred consecutive patients with trauma admitted to a surgical intensive care unit at a level I trauma center were prospectively analyzed. Demographics, acid-base data and diagnoses, and interventions were collected. Patients were cared for by one physician using a PC approach, or four using conventional (CONV) acid-base balance techniques. The diagnoses and interventions made by CONV physicians were reviewed by the PC physician for accuracy and appropriateness using PC techniques. Data are mean +/- SD or percents; p values reflect PC evaluation of CONV analysis., Results: There were 50 PC patients and 50 CONV. There were no differences in age (p = 0.13), injury severity score (p = 0.21), number of operations (p = 0.87), transfusions (p = 0.87), or survival (p = 0.15). CONV missed 12 diagnoses of metabolic acidosis (p = 0.03), 10 of hyperchloremic metabolic acidosis (p = 0.003), 11 metabolic alkalosis (p = 0.02), and 19 tertiary disorders (p < 0.001). CONV missed 38 diagnoses of increased unmeasured ions (p < 0.001). PC normalized their acid-base balance sooner than CONV (3.3 days +/- 3.4 days vs. 8.3 days +/- 7.4 days, p < 0.01)., Conclusions: A PC approach improves acid-base diagnosis accuracy. CONV often miss acidosis (particularly those because of hyperchloremia), alkalosis, and tertiary disorders. Inappropriate volume loading follows in the wake of misinterpretation of increased base deficit using CONV and is avoided using PC. PC-directed therapy normalizes acid-base balance more rapidly than CONV.

Acute renal failure frequently occurs in the intensive care unit as a primary or secondary event in association with trauma, surgery, or comorbid medical disease. An increasingly common thread linking surgical and medical disease management is the abdominal compartment syndrome. In particular, the rise of early goal-directed therapy for the initial resuscitation and management of severe sepsis and septic shock is associated with an increased frequency of secondary abdominal compartment syndrome. This paper will explore the pathophysiology underpinning the abdominal compartment syndrome and its contribution to acute kidney injury and acute renal failure with regard to intra-abdominal pressure dynamics, preload limitation, and afterload augmentation. Diagnostic modalities and therapeutic interventions will be addressed as a means of reducing the frequency of acute kidney injury and acute renal failure in the critically ill.

Background: Screening of pregnant women for vaginal and rectal carriage of group B streptococci may also identify group A streptococcal carriers. The clinical significance of prenatal group A streptococcal carriage is unknown., Cases: Two women developed group A streptococcal puerperal sepsis after delivery at one hospital 15 months apart. The first patient required hysterectomy and suffered complications including subcapsular hepatic hematoma, pleural effusion, and prolonged ileus. She recovered after a 35-day hospitalization. The second patient had endometritis and recovered. Both had had group A streptococci isolated from vaginal and rectal cultures taken for prenatal group B streptococcal screening. The acute sepsis isolates were both M-type 28, but pulsed-field gel electrophoresis determined that the strains were unrelated., Conclusions: Finding group A streptococci on prenatal culture may presage serious postpartum infection.

We examined the effect of caloric content and substrate composition on gastric emptying in conscious Sprague-Dawley rats using gastric radioscintigraphy. Three-milliliter volumes of normal saline, glucose, casein hydrolysate, or intralipid containing 0, 1, 2, 3, or 6 kcal labeled with 99mTc-diethylenetriaminepentaacetic acid were given intragastrically. Gamma-camera imaging and computer analysis allowed construction of gastric emptying curves constructed over many time points for each emptying study. There was no difference in the half-emptying times (t1/2) between different substrates with equal calories, and increasing calories significantly prolonged gastric emptying for all substrates. Emptying occurred in a linear fashion with meals containing calories. With 3-ml meals containing 2, 3, or 6 kcal, the rate of delivery of calories to the duodenum is constant regardless of substrate or change in caloric content. We conclude that the rate of caloric delivery to the small intestine with gastric infusion of 1-6 kcal is relatively constant despite differences in total caloric load, substrate composition, and osmolarity.

In order to determine the accuracy of computed tomographic (CT) scanning, CT scan results were compared with operative and pathologic findings in 45 patients with esophageal and proximal gastric malignancies. CT scans were evaluated with respect to nodal metastases, hepatic metastases, and adjacent spread. Eight patients did not undergo surgery because of advanced disease noted on the CT scan. Of the remaining 37 patients, sensitivity of CT for all 3 parameters was less than 60%, whereas the specificity was greater than 90%. The positive predictive value was greater than 90% for nodal metastases and adjacent spread and 67% for hepatic metastases. The negative predictive value was less than 40% for nodal metastases and adjacent spread and 90% for hepatic metastases. For esophageal and proximal gastric malignancies, CT is useful in identifying advanced disease and in predicting resectability. In less advanced cases, CT is not sensitive, and its negative predictive value is poor with regard to local and lymphatic spread. CT scanning is useful to stage the most advanced cases but because of limited accuracy should be combined with other diagnostic studies when accurate staging is required.