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Loving Jesus by Mark Allan Powell Fortress, Minneapolis, 2004. 200 pp. $16.00. ISBN 0-8006-3676-7. MARK ALLAN POWELL describes Christians as 'people who love Jesus,' and in this book he explores [...]

Scar tissue formation is a hallmark of wound repair in adults and can chronically affect tissue architecture and function. To understand the general phenomena, we sought to explore scar-driven imbalance in tissue homeostasis caused by a common, and standardized surgical procedure, the uterine scar due to cesarean surgery. Deep uterine scar is associated with a rapidly increasing condition in pregnant women, placenta accreta spectrum (PAS), characterized by aggressive trophoblast invasion into the uterus, frequently necessitating hysterectomy at parturition. We created a model of uterine scar, recapitulating PAS-like invasive phenotype, showing that scar matrix activates mechanosensitive ion channel, Piezo1, through glycolysis-fueled cellular contraction. Piezo1 activation increases intracellular calcium activity and Protein kinase C activation, leading to NF-κB nuclear translocation, and MafG stabilization. This inflammatory transformation of decidua leads to production of IL-8 and G-CSF, chemotactically recruiting invading trophoblasts towards scar, initiating PAS. Our study demonstrates aberrant mechanics of scar disturbs stroma-epithelia homeostasis in placentation, with implications in cancer dissemination., (© 2024. The Author(s).)

Neuroendocrine neoplasms commonly arise from the gastrointestinal tract and lungs. Less commonly, they may occur in the gynecologic tract, typically within the ovary of a mature cystic teratoma. Primary neuroendocrine neoplasms of the fallopian tube are exceptionally rare and only a total of 11 cases have been reported in the literature. We describe the first case to our knowledge of a primary grade 2 neuroendocrine tumor of the fallopian tube in a 47-yr-old female. In this report, we describe the case's unique presentation, review the published literature on primary neuroendocrine neoplasms of the fallopian tube, discuss the treatment options, and speculate on their origin and histogenesis., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 by the International Society of Gynecological Pathologists.)

Competing Interests: D.N. is a consultant for KLS and AtriCure and has patents related to pectus repair. All other authors have no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.

A platform to accelerate optimization of proteolysis targeting chimeras (PROTACs) has been developed using a direct-to-biology (D2B) approach with a focus on linker effects. A large number of linker analogs-with varying length, polarity, and rigidity-were rapidly prepared and characterized in four cell-based assays by streamlining time-consuming steps in synthesis and purification. The expansive dataset informs on linker structure-activity relationships (SAR) for in-cell E3 ligase target engagement, degradation, permeability, and cell toxicity. Unexpected aspects of linker SAR was discovered, consistent with literature reports on "linkerology", and the method dramatically speeds up empirical optimization. Physicochemical property trends emerged, and the platform has the potential to rapidly expand training sets for more complex prediction models. In-depth validation studies were carried out and confirm the D2B platform is a valuable tool to accelerate PROTAC design-make-test cycles., Competing Interests: The authors declare no competing financial interest., (© 2022 American Chemical Society.)

The general mechanisms by which ESCRTs (Endosomal Sorting Complexes Required for Transport) are specifically recruited to various membranes, and how ESCRT subunits are spatially organized remain central questions in cell biology. At the endosome and lysosomes, ubiquitination of membrane proteins triggers ESCRT-mediated substrate recognition and degradation. Using the yeast lysosome/vacuole, we define the principles by which substrate engagement by ESCRTs occurs at this organelle. We find that multivalent interactions between ESCRT-0 and polyubiquitin are critical for substrate recognition at yeast vacuoles, with a lower-valency requirement for cargo engagement at endosomes. Direct recruitment of ESCRT-0 induces dynamic foci on the vacuole membrane and forms fluid condensates in vitro with polyubiquitin. We propose that self-assembly of early ESCRTs induces condensation, an initial step in ESCRT assembly/nucleation at membranes. This property can be tuned specifically at various organelles by modulating the number of binding interactions.

Membrane contact sites are critical junctures for organelle signaling and communication. Endoplasmic reticulum-plasma membrane (ER-PM) contact sites were the first membrane contact sites to be described; however, the protein composition and molecular function of these sites is still emerging. Here, we leverage yeast and Drosophila model systems to uncover a novel role for the Hobbit (Hob) proteins at ER-PM contact sites. We find that Hobbit localizes to ER-PM contact sites in both yeast cells and the Drosophila larval salivary glands, and this localization is mediated by an N-terminal ER membrane anchor and conserved C-terminal sequences. The C-terminus of Hobbit binds to plasma membrane phosphatidylinositols, and the distribution of these lipids is altered in hobbit mutant cells. Notably, the Hobbit protein is essential for viability in Drosophila, providing one of the first examples of a membrane contact site-localized lipid binding protein that is required for development., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2021. Published by The Company of Biologists Ltd.)

Membrane protein recycling systems are essential for maintenance of the endosome-lysosome system. In yeast, retromer and Snx4 coat complexes are recruited to the endosomal surface, where they recognize cargos. They sort cargo and deform the membrane into recycling tubules that bud from the endosome and target to the Golgi. Here, we reveal that the SNX-BAR protein, Mvp1, mediates an endosomal recycling pathway that is mechanistically distinct from the retromer and Snx4 pathways. Mvp1 deforms the endosomal membrane and sorts cargos containing a specific sorting motif into a membrane tubule. Subsequently, Mvp1 recruits the dynamin-like GTPase Vps1 to catalyze membrane scission and release of the recycling tubule. Similarly, SNX8, the human homolog of Mvp1, which has been also implicated in Alzheimer's disease, mediates formation of an endosomal recycling tubule. Thus, we present evidence for a novel endosomal retrieval pathway that is conserved from yeast to humans., Competing Interests: SS, AO, NN, JJ, MB, SE No competing interests declared, (© 2021, Suzuki et al.)

Eukaryotic cells are compartmentalized into organelles by intracellular membranes. While the organelles are distinct, many of them make intimate contact with one another. These contacts were first observed in the 1950s, but only recently have the functions of these contact sites begun to be understood. In yeast, the endoplasmic reticulum (ER) makes extensive intermembrane contacts with the plasma membrane (PM), covering ∼40% of the PM. Many functions of ER-PM contacts have been proposed, including nonvesicular lipid trafficking, ion transfer, and as signaling hubs. Surprisingly, cells that lack ER-PM contacts grow well, indicating that alternative pathways may be compensating for the loss of ER-PM contact. To better understand the function of ER-PM contact sites we used saturating transposon mutagenesis to identify synthetic lethal mutants in a yeast strain lacking ER-PM contact sites. The strongest hits were components of the ESCRT complexes. The synthetic lethal mutants have low levels of some lipid species but accumulate free fatty acids and lipid droplets. We found that only ESCRT-III components are synthetic lethal, indicating that Vps4 and other ESCRT complexes do not function in this pathway. These data suggest that ESCRT-III proteins and ER-PM contact sites act in independent pathways to maintain lipid homeostasis.

Objectives: Unplanned hospital admission following chemotherapy is a measure of quality cancer care. Large retrospective datasets have shown admission rates of 10-35% for women with ovarian cancer receiving chemotherapy. We sought to evaluate the prevalence and associated risk factors for hospital admission following chemotherapy in our racially diverse urban population., Methods: After IRB approval, clinicopathologic and treatment data were abstracted from all patients with newly diagnosed epithelial ovarian cancer who received chemotherapy at our institution from 2005 to 2016. Two-sided statistical analyses and Cox regression analysis were performed using Stata., Results: Of 217 evaluable patients, 87 (40%) had unplanned admissions following chemotherapy: adjuvant 64 (74%) and neoadjuvant 23(26%). Thirty (14%) had more than one admission. In total, there were 1314 days of hospitalization. The median readmission duration was 3 days. Body mass index and hypertension were predictive of readmission (p < 0.05). When comparing those readmitted more than once to those admitted once, both race and aspirin use were predictive of readmission (p < 0.05). Of those admitted more than once the self-identified race and ethnicity was 12 (40%) Hispanic, 8 (27%) White, 8 (27%) Black and 2 (7%) other. There was a significant difference in disease free (p = 0.01) and overall survival (p = 0.004) for patients with unplanned admission after chemotherapy as compared to those without admission., Conclusions: Readmission rates in our racially diverse patient population were higher than previously reported in the literature. Identifying patients at risk of readmission may play a role in chemotherapy decision-making, and resource allocation including patient care navigators., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The lysosome plays an important role in maintaining cellular nutrient homeostasis. Regulation of nutrient storage can occur by the ubiquitination of certain transporters that are then sorted into the lysosome lumen for degradation. To better understand the underlying mechanism of this process, we performed genetic screens to identify components of the sorting machinery required for vacuole membrane protein degradation. These screens uncovered genes that encode a ubiquitin ligase complex, components of the PtdIns 3-kinase complex, and the ESCRT machinery. We developed a novel ubiquitination system, Rap amycin -I nduced Deg radation (RapiDeg), to test the sorting defects caused by these mutants. These tests revealed that ubiquitinated vacuole membrane proteins recruit ESCRTs to the vacuole surface, where they mediate cargo sorting and direct cargo delivery into the vacuole lumen. Our findings demonstrate that the ESCRTs can function at both the late endosome and the vacuole membrane to mediate cargo sorting and intra-luminal vesicle formation.

Objective: To investigate whether the 2006 American Society for Colposcopy and Cervical Pathology guidelines for conservative management of minimally abnormal Pap test results (atypical squamous cells of undetermined significance, human papillomavirus-positive, and low-grade squamous intraepithelial lesions) and moderate dysplasia (cervical intraepithelial neoplasia 2) in adolescents 1) resulted in fewer colposcopies and loop electrosurgical excision procedures (LEEPs) in adolescents or 2) resulted in unintended treatment changes in older age groups., Methods: We analyzed data from 1,806 women aged 18 years and older attending one of six community health centers who were diagnosed with abnormal Pap test results between January 1, 2004, and December 31, 2008. We used multivariable logistic regression to examine treatment differences in women with minimally abnormal Pap test results before and after guideline changes. Variables included date of abnormality, site of care, race or ethnicity, language, and insurance type. We used Fisher exact tests to examine rates of LEEP in patients with moderate dysplasia before and after guideline publication., Results: Among 206 women aged 18-20 years, rates of colposcopy after a minimally abnormal Pap test result decreased from 78% (n=102) to 45% (n=34) after guideline changes (P<.001). Colposcopy among women over age 21 (n=1,542) remained unchanged (greater than 90%). Multivariable logistic regression indicated that both date of abnormality and site of care were associated with colposcopy referral. After guideline changes, management of moderate dysplasia with LEEP in women aged 18-23 decreased from 55% to 18% (P=.04); rates remained stable in women ages 24 and older (70% compared with 74%; P=.72)., Conclusion: Health care providers quickly adopted new conservative management guidelines for low-income, minority adolescents, which may reduce preterm deliveries in these high-risk populations., Level of Evidence: II.

In the P-domain, the 369-DKTGTLT and the 709-GDGVNDSPALKK segment are highly conserved during evolution of P-type E1-E2-ATPase pumps irrespective of their cation specificities. The focus of this article is on evaluation of the role of the amino acid residues in the P domain of the alpha subunit of Na,K-ATPase for the E1P[3Na]--> E2P[2Na] conversion, the K+-activated dephosphorylation, and the transmission of these changes to and from the cation binding sites. Mutations of residues in the TGDGVND loop show that Asp710 is essential, and Asn713 is important, for Mg2+ binding and formation of the high-energy MgE1P[3Na] intermediate. In contrast Asp710 and Asp713 do not contribute to Mg2+ binding in the E2P-ouabain complex. Transition to E2P thus involves a shift of Mg2+ coordination away from Asp710 and Asn713 and the two residues become more important for K+-activated hydrolysis of the acyl phosphate bond at Asp369. Transmission of structural changes between the P-domain and cation sites in the membrane domain is evaluated in light of the protein structure, and the information from proteolytic or metal-catalyzed cleavage and mutagenesis studies.

The segment (708)TGDGVNDSPALKK(720) in the alpha-subunit P domain of Na,K-ATPase is highly conserved among cation pumps, but little is known about its role in binding of Mg(2+) or ATP and energy transduction. Here, 11 mutations of polar residues are expressed at reduced temperature in yeast with preserved capacities for high affinity binding of ouabain and ATP, whereas the Thr(708) --> Ser mutation and alterations of Asp(714) abolish all catalytic reactions. In mutations of Asp(710) and Asn(713), ATP affinity is preserved or increased, whereas Na,K-ATPase activity is severely reduced. Assay of phosphorylation from ATP in the presence of oligomycin shows that Asp(710) contributes to coordination of Mg(2+) during transfer of gamma-phosphate to Asp(369) in the high energy Mg.E(1)P[3Na] intermediate and that Asn(713) is involved in these processes. In contrast, Asp(710) and Asp(713) do not contribute to Mg(2+) binding in the E(2)P.ouabain complex. Transition to E(2)P thus involves a shift of Mg(2+) coordination away from Asp(710) and Asn(713), and the two residues become more important for hydrolysis of the acyl phosphate bond at Asp(369). The Asp(710) --> Ala mutation blocks interaction with vanadate, whereas Asn(713) --> Ala interferes with phosphorylation from P(i) of the E(2).ouabain complex, showing that the GDGVND segment is required for stabilization of the transition state and for the phosphorylation reaction. The Asp(710) --> Ala mutation also interferes with transmission of structural changes to the ouabain site and reduces the affinity for binding of Tl(+) 2- to 3-fold, suggesting a role in transmission of K(+) stimulation of phospho-enzyme hydrolysis from transmembrane segment 5 to the P domain.

In patients treated with sulfinpyrazone, an apparent reduction in the incidence of sudden death and presumed ventricular fibrillation has been reported. Using an intact animal model without microcirculatory thrombosis, we studied the effects of sulfinpyrazone on ischemic myocardium in 58 anesthetized dogs divided into three groups: control untreated (n =24), group 1 (n = 16), treated daily with 300 mg of sulfinpyrazone for 7 days, and group 2 (n = 18), treated daily with 300 mg of sulfinpyrazone for 7 days but omitting treatment on day 8. Although consistent hemodynamic differences were not apparent, the degree of injury determined by ECG mapping was significantly lower in group 1. The incidence of fibrillation was 54% for control and 0% in group 1. Group 2 had a 44% incidence, suggesting a limited duration of action. The apparent absence of microcirculatory thrombosis in this model suggests other mechanisms of action. A significantly smaller increase in tissue water and Na+ and smaller loss of K+ in group 1 may have contributed to the lower incidence of fibrillation, perhaps through selective prostaglandin inhibition.

The effects of administered human growth hormone (HGH) were evaluated in dwarfed, prepubertal children who were receiving long-term corticosteroid therapy for a chronic disease. During 11 complete metabolic balance studies, the eight corticosteroid-treated children demonstrated impaired response to large doses of HGH with minimal nitrogen and no phosphorus retention. In contrast, two hypopituitary subjects and two asthmatic children not receiving corticosteroid responded to the same preparations of HGH with nitrogen, potassium, and phosphorus retention. Six corticosteroid-treated children were given large doses of HGH (40-120 mg/wk for 4 to 8 months and showed no improvement in their retarded rate of growth, whereas the hypopituitary subjects showed accelerated growth during administration of 10-15 mg of HGH/wk. It is concluded that dwarfism in steroid-treated children results from corticosteroid-induced antagonism of the effects of HGH at the peripheral tissue level.

Endogenous plasma growth hormone concentrations were measured in 23 children who were receiving daily corticosteroid therapy and in 10 control asthmatic children who had not received steroids for at least 8 months. The growth hormone concentrations were similar in the two groups of patients both during the fasting state and after insulin-induced hypoglycemia. 12 children, who were studied while receiving a large dose of prednisone and again 2 wk after steroid withdrawal, also showed no change in growth hormone concentration in relation to corticosteroid therapy. These findings suggest that deficiency of growth hormone is not the major mechanism responsible for the dwarfism of corticosteroid-treated children.