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Purpose: Anterior cruciate ligament (ACL) reconstruction surgery is common, with significant postoperative pain. Few studies have assessed gabapentin for pain in adolescent ACL populations. Design: A feasibility study measured efficacy of single preoperative gabapentin doses to reduce postoperative pain in adolescents aged 12 to 18 years undergoing ACL reconstruction versus placebo. Methods: Primary efficacy outcome was postoperative opioid use, with pain, safety, and pain management satisfaction secondary. Findings: Fifty-five patients enrolled. Gabapentin had an early effect in reducing mean narcotic use 24 hours postoperatively. No significant difference was demonstrated overall in the two groups. Over half of patients were still taking opioids at day 4/5; current guidelines recommend 3 days or less. Median satisfaction score, one point higher for gabapentin group versus placebo group, was not statistically significant. Conclusion: Results demonstrate gabapentin may be an effective medication to reduce acute postoperative pain. However, robust methodology is needed to more accurately assess and treat pain. Key Words: Postoperative pain, gabapentin, non-opioids, outpatient anterior cruciate ligament (ACL) surgery, pain management education., Anterior cruciate ligament (ACL) reconstruction is an increasingly common surgery among adolescents. Limited epidemiological information is available concerning ACL injuries in pediatrics, but a descriptive study from the state of [...]

In this article, we report a wearable magnetic-reluctance-based wireless pressure sensing module to measure intraoral pressure for clinical orthodontic treatment. The sensing module consists of two parts: first part is a transmitting/receiving electromagnet (EM $_{\mathrm {T}}$ ) which is connected to a reference electromagnet (EM $_{\mathrm {R}}$ ); second part is a high-permeable sensing diaphragm embedded into a bi-layered wearable orthodontic aligner. These electromagnets are placed outside of the mouth, while the aligner (consisting of the sensing diaphragm) is placed inside of the mouth. An ac current is applied to the transmitting electromagnet to produce ac magnetic flux, consequently by the electromagnetic induction, an ac voltage is induced in the receiving electromagnet. When people use cheek muscle (i.e., stress the cheek muscle), pressure in the oral cavity is changed. Consequently, a pressure difference is formed to deflect the sensing diaphragm toward or backward the EMT. Due to this, the magnetic reluctance between the sensing diaphragm and the EMT is changed. Through the electromagnetic induction, voltage output is induced in the receiving electromagnet. By analyzing the voltage output, we can know the change of the pressure. Based on above principle, we fabricated above parts and conducted pressure sensing test. According to the test results, the sensing module successfully senses the pressure ranging from 0 to 30 kPa with a sensitivity of 3.52 to $0.82 \mu \text{V}$ /kPa, when the EMT is placed 7–13 mm away from the sensing module respectively. This achieves the wearable wireless intraoral pressure sensing and consequently provides useful monitoring information for clinical orthodontic treatment.

IMPORTANCE: Early intervention using cone-beam computed tomography (CBCT) and adenotonsillectomy for children with obstructive sleep apnea (OSA) may prevent impaired growth, adverse cardiovascular consequences, learning deficits, and poor quality of life. OBJECTIVE: To assess changes in CBCT airway measurements and polysomnography (PSG) parameters that occur after adenotonsillectomy in children with OSA and to determine whether CBCT changes are correlated with apnea-hypopnea index (AHI) reduction. DESIGN, SETTING, AND PARTICIPANTS: This prospective cohort study was conducted at a tertiary medical center from 2013 to 2016. Children aged 7 to 13 years with PSG-confirmed OSA (ie, AHI ≥1) were recruited. Data analysis was performed from March to July 2021. EXPOSURES: All participants underwent CBCT and PSG before and after adenotonsillectomy. MAIN OUTCOMES AND MEASURES: Changes in PSG and CBCT parameters after adenotonsillectomy were analyzed. RESULTS: A total of 49 children (mean [SD] age, 9.5 [1.8] years; 34 boys [69.4%]) were recruited. Eighteen participants (36.7%) had obesity. After adenotonsillectomy, AHI significantly decreased from 11.4 to 1.2 events per hour (mean difference, −10.24 events per hour; 95% CI, −13.84 to −6.64 events per hour). The following CBCT parameters significantly increased: total airway volume (from 11 265 to 15 161 mm3; mean difference, 3896.6 mm3; 95% CI, 2788.0 to 5005.2 mm3), nasopharyngeal volume (from 2366 to 3826 mm3; mean difference, 1459.7 mm3; 95% CI, 1122.9 to 1796.5 mm3), minimal nasopharyngeal airway area (from 128 to 191 mm2; mean difference, 63.1 mm2; 95% CI, 47.4 to 78.8 mm2), mean nasopharyngeal airway area (from 144 to 231 mm2; mean difference, 86.8 mm2; 95% CI, 67.0 to 106.5 mm2), oropharyngeal volume (from 8898 to 11 335 mm3; mean difference, 2436.9 mm3; 95% CI, 1477.0 to 3396.8 mm3), minimal oropharyngeal airway area (from 82 to 158 mm2; mean difference, 76.2 mm2; 95% CI, 57.0 to 95.4 mm2), and mean oropharyngeal airway area (from 182 to 234 mm2; mean difference, 52.5 mm2; 95% CI, 33.6 to 71.4 mm2). Among all parameters, only body mass index percentile showed large effect size between the group with residual OSA (postoperative AHI ≥1) and the group with resolved disease, with the residual OSA group having a higher body mass index percentile (87.8 vs 61.4; mean difference, 26.33; 95% CI, 10.00 to 42.66). A quantile regression model revealed that total airway volume and minimal oropharyngeal airway area were significantly correlated with reductions in AHI. CONCLUSIONS AND RELEVANCE: These findings suggest that in children undergoing adenotonsillectomy, improvements in total airway volume and oropharyngeal minimal airway area were correlated with reduction of AHI. Future studies are needed to assess whether CBCT has a role in the evaluation of children with OSA who are being considered for adenotonsillectomy.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.amjmed.2007.01.026 Byline: Margaret C. Fang (a), Jane Chen (b), Michael W. Rich (b) Keywords: Anti-arrhythmic; Anticoagulants; Atrial fibrillation; Elderly; Hemorrhage; Rate control; Rhythm control; Stroke Abstract: Atrial fibrillation is increasingly prevalent among older adults. It causes approximately 24% of strokes in patients aged 80 to 89 years. The management of atrial fibrillation is directed at preventing thromboembolism and controlling the heart rate and rhythm. Stroke prevention is most effectively accomplished through administering anticoagulants such as warfarin, although older patients have higher hemorrhagic risk. Cognitive dysfunction, functional impairments, and increased fall risk further complicate warfarin management in elderly patients. The use of risk stratification schemes can help guide the anticoagulation decision, although the benefits of warfarin generally outweigh the risks in most older patients with atrial fibrillation. Pharmacologic rate control has been shown to result in similar outcomes compared with pharmacologic restoration of sinus rhythm and should be the initial therapy for elderly patients. Anti-arrhythmic medications should be selected based on an individual patient's coexisting medical conditions. In symptomatic patients who fail pharmacologic therapy, invasive strategies such as AV nodal ablation may help improve quality of life and symptoms, although such strategies do not obviate the need for antithrombotic therapy. Author Affiliation: (a) Division of General Internal Medicine Hospitalist Group, University of California, San Francisco (b) Cardiovascular Division, Washington University School of Medicine, St. Louis, Mo.

Background HIV and other sexually transmitted infections (STIs) have disproportionately affected communities of men who have sex with men (MSM). We describe HIV and STI prevalence and testing patterns among urban Vietnamese MSM.Methods We conducted a cross-sectional community-based study of MSM in Hanoi, Vietnam in 2016. Participants self-reported experiences of social stigma in healthcare settings and previous HIV and STI testing. STI testing included HIV, herpes simplex virus-2 (HSV-2), syphilis, gonorrhea, and chlamydia.Results 205 MSM participated in the study. STI prevalence was HIV (10%), HSV-2 (4%), syphilis (13%), gonorrhea (34%), and chlamydia (19%). More than half (55%) of participants tested positive for at least one STI. Most participants had been previously tested for HIV or another STI (72%), with 24% previously receiving a positive result. Perceived and enacted social stigma in healthcare contexts was negatively associated with previous HIV or STI testing (adjusted prevalence odds ratio (aPOR): 0.22; 95% confidence interval (CI): 0.10–0.48).Discussion High prevalence of STIs was observed among Vietnamese MSM, and perceived and enacted stigma was related to HIV and STI testing. Our findings reaffirm the importance of regular STI screening among this population as well as additional outreach to promote safe HIV and STI healthcare engagement.

Transverse problems can be exacerbated by highly compensated occlusion in patients with skeletal asymmetry, which makes pre-surgical decompensation harder to achieve.

Increased production of fetal hemoglobin (HbF) can ameliorate the severity of sickle cell disease and β-thalassemia1. BCL11A represses the genes encoding HbF and regulates human hemoglobin switching through variation in its expression during development2–7. However, the mechanisms underlying the developmental expression of BCL11A remain mysterious. Here we show that BCL11A is regulated at the level of messenger RNA (mRNA) translation during human hematopoietic development. Despite decreased BCL11A protein synthesis earlier in development, BCL11AmRNA continues to be associated with ribosomes. Through unbiased genomic and proteomic analyses, we demonstrate that the RNA-binding protein LIN28B, which is developmentally expressed in a pattern reciprocal to that of BCL11A, directly interacts with ribosomes and BCL11AmRNA. Furthermore, we show that BCL11AmRNA translation is suppressed by LIN28B through direct interactions, independently of its role in regulating let-7 microRNAs, and that BCL11A is the major target of LIN28B-mediated HbF induction. Our results reveal a previously unappreciated mechanism underlying human hemoglobin switching that illuminates new therapeutic opportunities.

As essential components of hemoglobin, iron and heme play central roles in terminal erythropoiesis. The impairment of this process in iron/heme deficiency results in microcytic hypochromic anemia, the most prevalent anemia globally. Heme-regulated eIF2a kinase, also known as heme-regulated inhibitor (HRI), is a key heme-binding protein that senses intracellular heme concentrations to balance globin protein synthesis with the amount of heme available for hemoglobin production. HRI is activated during heme deficiency to phosphorylate eIF2a (eIF2aP), which simultaneously inhibits the translation of globin messenger RNAs (mRNAs) and selectively enhances the translation of activating transcription factor 4 (ATF4) mRNA to induce stress response genes. This coordinated translational regulation is a universal hallmark across the eIF2a kinase family under various stress conditions and is termed the integrated stress response (ISR). Inhibition of general protein synthesis by HRI-eIF2aP in erythroblasts is necessary to prevent proteotoxicity and maintain protein homeostasis in the cytoplasm and mitochondria. Additionally, the HRI–eIF2aP–ATF4 pathway represses mechanistic target of rapamycin complex 1 (mTORC1) signaling, specifically in the erythroid lineage as a feedback mechanism of erythropoietin-stimulated erythropoiesis during iron/heme deficiency. Furthermore, ATF4 target genes are most highly activated during iron deficiency to maintain mitochondrial function and redox homeostasis, as well as to enable erythroid differentiation. Thus, heme and translation regulate erythropoiesis through 2 key signaling pathways, ISR and mTORC1, which are coordinated by HRI to circumvent ineffective erythropoiesis (IE). HRI-ISR is also activated to reduce the severity of ß-thalassemia intermedia in the Hbbth1/th1 murine model. Recently, HRI has been implicated in the regulation of human fetal hemoglobin production. Therefore, HRI-ISR has emerged as a potential therapeutic target for hemoglobinopathies.

All Myeloproliferative neoplasms (MPN) driver mutations converge on the activation of thrombopoietin receptor (MPL) signaling. Somatic frameshift mutations in calreticulin (CALR), leading to a novel peptide sequence are seen in 20-30% of patients with essential thrombocythemia or myelofibrosis. CALR is a multifunctional calcium-binding protein that is primarily localized to the endoplasmic reticulum (ER) of cells. It plays important roles in calcium homeostasis, protein folding, and quality control within the ER. MPN associated CALR mutants bind to and activate MPL resulting in constitutive activation of signaling.

Background and Significance:

Clonal hematopoiesis of intermediate potential (CHIP) increases the risk for hematological malignancies and cardiovascular disease with Jak2 being a commonly mutated gene in CHIP. Age is the strongest determinant of CHIP but environmental factors also play a role since only a fraction of the individuals with CHIP eventually present with overt clonal hematopoiesis. The popularity of electronic (E-) cigarette (E-cig) usage has increased but their health effects are not well-established. E-cigarettes have been associated with inflammation and oxidative stress and these can provide a selective pressure for the outgrowth of CHIP mutant cells. Here, we determined the impact of E-cig aerosol inhalation on the survival and/or expansion of Jak2 mutant hematopoietic cells by exposing bone marrow transplanted mice to E-cig aerosols.

Although the role of classic driver mutations (i.e., JAK2, MPL, and CALR) in myeloproliferative neoplasm (MPN) development is well characterized, additional somatic mutations likely modulate the phenotype. Recurrent somatic mutations, such as those in TET2, DNMT3A, ASXL1genes are commonly identified in MPN using targeted myeloid panels, however identification of somatic mutations using an unbiased approach may unveil novel pathways involved in MPN pathogenesis.

IMPORTANCE: Incentive spirometers (ISs) were developed to reduce atelectasis and are in widespread clinical use. However, without IS use adherence data, the effectiveness of IS cannot be determined. OBJECTIVE: To evaluate the effect of a use-tracking IS reminder on patient adherence and clinical outcomes following coronary artery bypass grafting (CABG) surgery. DESIGN, SETTING, AND PARTICIPANTS: This randomized clinical trial was conducted from June 5, 2017, to December 29, 2017, at a tertiary referral teaching hospital and included 212 patients who underwent CABG, of whom 160 participants were randomized (intent to treat), with 145 completing the study per protocol. Participants were stratified by surgical urgency (elective vs nonelective) and sex (men vs women). INTERVENTIONS: A use-tracking, IS add-on device (SpiroTimer) with an integrated use reminder bell recorded and timestamped participants’ inspiratory breaths. Patients were randomized by hourly reminder “bell on” (experimental group) or “bell off” (control group). MAIN OUTCOMES AND MEASURES: Incentive spirometer use was recorded for the entire postoperative stay and compared between groups. Radiographic atelectasis severity (score, 0-10) was the primary clinical outcome. Secondary respiratory and nonrespiratory outcomes were also evaluated. RESULTS: A total of 145 per-protocol participants (112 men [77%]; mean age, 69 years [95% CI, 67-70]; 90 [62%] undergoing a nonelective procedure) were evaluated, with 74 (51.0%) in the bell off group and 71 (49.0%) in the bell on group. The baseline medical and motivation-to-recover characteristics of the 2 groups were similar. The mean number of daily inspiratory breaths was greater in bell on (35; 95% CI, 29-43 vs 17; 95% CI, 13-23; P < .001). The percentage of recorded hours with an inspiratory breath event was greater in bell on (58%; 95% CI, 51-65 vs 28%; 95% CI, 23-32; P < .001). Despite no differences in the first postoperative chest radiograph mean atelectasis severity scores (2.3; 95% CI, 2.0-2.6 vs 2.4; 95% CI, 2.2-2.7; P = .48), the mean atelectasis severity scores for the final chest radiographs conducted before discharge were significantly lower for bell on than bell off group (1.5; 95% CI, 1.3-1.8 vs 1.8; 95% CI, 1.6-2.1; P = .04). Of those with early postoperative fevers, fever duration was shorter for bell on (3.2 hours; 95% CI, 2.3-4.6 vs 5.2 hours; 95% CI, 3.9-7.0; P = .04). Having the bell turned on reduced noninvasive positive pressure ventilation use rates (37.2%; 95% CI, 24.1%-52.5% vs 19.2%; 95% CI, 10.2%-33.0%; P = .03) for participants undergoing nonelective procedures. Bell on reduced the median postoperative length of stay (7 days; 95% CI, 6-9 vs 6 days; 95% CI, 6-7; P = .048) and the intensive care unit length of stay for patients undergoing nonelective procedures (4 days; 95% CI, 3-5 vs 3 days; 95% CI, 3-4; P = .02). At 6 months, the bell off mortality rate was higher than bell on (9% vs 0%, P = .048) for participants undergoing nonelective procedures. CONCLUSIONS AND RELEVANCE: The incentive spirometer reminder improved patient adherence, atelectasis severity, early postoperative fever duration, noninvasive positive pressure ventilation use, ICU and length of stay, and 6-month mortality in certain patients. With the reminder, IS appears to be clinically effective when used appropriately. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02952027

Diamond-Blackfan anemia (DBA) is a congenital erythroblastopenia that is characterized by a blockade in erythroid differentiation related to impaired ribosome biogenesis. DBA phenotype and genotype are highly heterogeneous. We have previously identified 2 in vitro erythroid cell growth phenotypes for primary CD34+cells from DBA patients and following short hairpin RNA knockdown of RPS19, RPL5, and RPL11 expression in normal human CD34+cells. The haploinsufficient RPS19 in vitro phenotype is less severe than that of 2 other ribosomal protein (RP) mutant genes. We further documented that proteasomal degradation of HSP70, the chaperone of GATA1, is a major contributor to the defect in erythroid proliferation, delayed erythroid differentiation, increased apoptosis, and decreased globin expression, which are all features of the RPL5 or RPL11 DBA phenotype. In the present study, we explored the hypothesis that an imbalance between globin and heme synthesis may be involved in pure red cell aplasia of DBA. We identified disequilibrium between the globin chain and the heme synthesis in erythroid cells of DBA patients. This imbalance led to accumulation of excess free heme and increased reactive oxygen species production that was more pronounced in cells of the RPL5 or RPL11 phenotype. Strikingly, rescue experiments with wild-type HSP70 restored GATA1 expression levels, increased globin synthesis thereby reducing free heme excess and resulting in decreased apoptosis of DBA erythroid cells. These results demonstrate the involvement of heme in DBA pathophysiology and a major role of HSP70 in the control of balanced heme/globin synthesis.

Chronic pancreatitis (CP) is an inflammatory disease that causes progressive damage to the pancreatic parenchyma with irreversible morphological changes and fibrotic replacement of the gland. The risk factors associated with developing CP have been described as toxic (e.g., alcohol and tobacco); idiopathic (e.g., unknown); genetic, autoimmune, recurrent acute pancreatitis, and obstructive (the TIGAR-O system). Upon histological screening of the pancreata from a cohort of CP patients who had undergone pancreatectomy for the treatment of intractable pain in Leicester, UK, one sample showed a striking change in the morphological balance toward an endocrine phenotype, most notably there was evidence of substantial α cell genesis enveloping entire cross sections of ductal epithelium and the presence of α cells within the ductal lumens. This patient had previously undergone a partial pancreatectomy, had severe sclerosing CP, an exceptionally low body mass index (15.2), and diabetes at the time the pancreas was removed, and although these factors have been shown to induce tissue remodeling, such high levels of α cells was an unusual finding within our series of patients. Due to the fact that α cells have been shown to be the first endocrine cell type that emerges during islet neogenesis, future research profiling the factors that caused such marked α cell genesis may prove useful in the field of islet transplantation.

T cells are strongly regulated by oxidizing environments and amino acid restriction. How T cells reprogram metabolism to adapt to these extracellular stress situations is not well understood. Here, we show that oxidizing environments and amino acid starvation induce ATF4 in CD4+T cells. We also demonstrate that Atf4-deficient CD4+T cells have defects in redox homeostasis, proliferation, differentiation, and cytokine production. We further reveal that ATF4 regulates a coordinated gene network that drives amino acid intake, mTORC1 activation, protein translation, and an anabolic program for de novosynthesis of amino acids and glutathione. ATF4 also promotes catabolic glycolysis and glutaminolysis and oxidative phosphorylation and thereby provides precursors and energy for anabolic pathways. ATF4-deficient mice mount reduced Th1 but elevated Th17 immune responses and develop more severe experimental allergic encephalomyelitis (EAE). Our study demonstrates that ATF4 is critical for CD4+T cell-mediated immune responses through driving metabolic adaptation.

Iron deficiency (ID) anemia is a prevalent disease, yet molecular mechanisms by which iron and heme regulate erythropoiesis are not completely understood. Heme-regulated eIF2α kinase (HRI) is a key hemoprotein in erythroid precursors that sense intracellular heme concentrations to balance globin synthesis with the amount of heme available for hemoglobin production. HRI is activated by heme deficiency and oxidative stress, and it phosphorylates eIF2α (eIF2αP), which inhibits the translation of globin messenger RNAs (mRNAs) and selectively enhances the translation of activating transcription factor 4 (ATF4) mRNA to induce stress response genes. Here, we generated a novel mouse model (eAA) with the erythroid-specific ablation of eIF2αP and demonstrated that eIF2αP is required for induction of ATF4 protein synthesis in vivo in erythroid cells during ID. We show for the first time that both eIF2αP and ATF4 are necessary to promote erythroid differentiation and to reduce oxidative stress in vivo during ID. Furthermore, the HRI-eIF2αP-ATF4 pathway suppresses mTORC1 signaling specifically in the erythroid lineage. Pharmacologic inhibition of mTORC1 significantly increased red blood cell counts and hemoglobin content in the blood, improved erythroid differentiation, and reduced splenomegaly of iron-deficient Hri−/− and eAA mice. However, globin inclusions and elevated oxidative stress remained, demonstrating the essential nonredundant role of HRI-eIF2αP in these processes. Dietary iron repletion completely reversed ID anemia and ineffective erythropoiesis of Hri−/−, eAA, and Atf4−/− mice by inhibiting both HRI and mTORC1 signaling. Thus, HRI coordinates 2 key translation-regulation pathways, eIF2αP and mTORC1, to circumvent ineffective erythropoiesis, highlighting heme and translation in the regulation of erythropoiesis.

Background:Huntington’s disease (HD) is a fatal, inherited neurodegenerative disorder characterized by uncontrollable dance-like movements, as well as cognitive deficits and mood changes. A feature of HD is a metabolic disturbance that precedes neurological symptoms. In addition, brain cholesterol synthesis is significantly reduced, which could hamper synaptic transmission. Objective:Alterations in lipid metabolism as a potential target for therapeutic intervention in the R6/2 mouse model of HD were examined. Methods:Electrophysiological recordings in vitroexamined the acute effects of cholesterol-modifying drugs. In addition, behavioral testing, effects on synaptic activity, and measurements of circulating and brain tissue concentrations of cholesterol and the ketone β-hydroxybutyrate (BHB), were examined in symptomatic R6/2 mice and littermate controls raised on normal chow or a ketogenic diet (KD). Results:Whole-cell voltage clamp recordings of striatal medium-sized spiny neurons (MSNs) from symptomatic R6/2 mice showed increased frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) compared with littermate controls. Incubation of slices in cholesterol reduced the frequency of large-amplitude sIPSCs. Addition of BHB or the Liver X Receptor (LXR) agonist T0901317 reduced the frequency and amplitude of sIPSCs. Surprisingly, incubation in simvastatin to reduce cholesterol levels also decreased the frequency of sIPSCs. HD mice fed the KD lost weight more gradually, performed better in an open field, had fewer stereotypies and lower brain levels of cholesterol than mice fed a regular diet. Conclusions:Lipid metabolism represents a potential target for therapeutic intervention in HD. Modifying cholesterol or ketone levels acutely in the brain can partially rescue synaptic alterations, and the KD can prevent weight loss and improve some behavioral abnormalities.

This review will provide an overview of the translational regulation of globin mRNAs and integrated stress response (ISR) during erythropoiesis by heme-regulated eIF2 kinase (HRI). HRI is an intracellular heme sensor that coordinates heme and globin synthesis in erythropoiesis by inhibiting protein synthesis of globins and heme biosynthetic enzymes during heme deficiency.

Graphene and graphene-based nanomaterials display novel and beneficial chemical, electrical, mechanical, and optical characteristics, which endow these nanomaterials with promising applications in a wide spectrum of areas such as electronics and biomedicine. However, its toxicity on health remains unknown and is of great concern. In the present study, we demonstrated that graphene oxide (GO) induced necrotic cell death to macrophages. This toxicity is mediated by activation of toll-like receptor 4 (TLR4) signaling and subsequently in part viaautocrine TNF-α production. Inhibition of TLR4 signaling with a selective inhibitor prevented cell death nearly completely. Furthermore, TLR4-deficient bone marrow-derived macrophages were resistant to GO-triggered necrosis. Similarly, GO did not induce necrosis of HEK293T/TLR4-null cells. Macrophagic cell death upon GO treatment was partially attributed to RIP1-RIP3 complex-mediated programmed necrosis downstream of TNF-α induction. Additionally, upon uptake into macrophages, GO accumulated primarily in cytoplasm causing dramatic morphologic alterations and a significant reduction of the macrophagic ability in phagocytosis. However, macrophagic uptake of GO may not be required for induction of necrosis. GO exposure also caused a large increase of intracellular reactive oxygen species (ROS), which contributed to the cause of cell death. The combined data reveal that interaction of GO with TLR4 is the predominant molecular mechanism underlying GO-induced macrophagic necrosis; also, cytoskeletal damage and oxidative stress contribute to decreased viability and function of macrophages upon GO treatment.

Tp53 mutations are common in human prostate cancer (CaP), occurring with a frequency of ∼30% and ∼70% in localized and metastatic disease, respectively. In vitro studies have determined several common mutations of Tp53 that have specific gain-of-function properties in addition to loss of function, including the ability to promote castration-resistant (CR) growth of CaP cells in some contexts. To date, a lack of suitable mouse models has prohibited investigation of the role played by Tp53 mutations in mediating CaP progression in vivo. Here, we describe the effects of conditional expression of a mutant Tp53 (Tp53R270H; equivalent to the human hotspot mutant R273H) in the prostate epithelium of mice. Heterozygous “Tp53LSL-R270H/+” [129S4(Trp53tm3Tyj)] and “Nkx3.1-Cre” [129S(Nkx3-1tm3(cre)Mms)] mice with prostate-specific expression of the Tp53R270H mutation (p53R270H/+ Nkx3.1-Cre mice) were bred onto an FVB/N background via speed congenesis to produce strain FVB.129S4(Trp53tm3Tyj/wt); FVB.129S(Nkx3-1tm3(cre)Mms/wt) and littermate genotype negative control mice. These mutant mice had significantly increased incidences of prostatic intraepithelial neoplasia (PIN) lesions, and these appeared earlier, compared with the Nkx3.1 haploinsufficient (Nkx3.1-Cre het) littermate mice, which did not express the Tp53 mutation. PIN lesions in these mice showed consistent progression and some developed into invasive adenocarcinoma with a high grade, sarcomatoid or epithelial-mesenchymal transition (EMT) phenotype. PIN lesions were similar to those seen in PTEN conditional knockout mice, with evidence of AKT activation concomitant with neoplastic proliferation. However, the invasive tumor phenotype is rarely seen in previously described mouse models of prostatic neoplasia. These data indicate that the Tp53R270H mutation plays a role in CaP initiation. This finding has not previously been reported. Further characterization of this model, particularly in a setting of androgen deprivation, should allow further insight into the mechanisms by which the Tp53R270H mutation mediates CaP progression.

Heme-regulated eIF2α kinase (Hri) is necessary for balanced synthesis of heme and globin. In addition, Hri deficiency exacerbates the phenotypic severity of β-thalassemia intermediain mice. Activation of Hri during heme deficiency and in β-thalassemia increases eIF2α phosphorylation and inhibits globin translation. Under endoplasmic reticulum stress and nutrient starvation, eIF2α phosphorylation also induces the Atf4 signaling pathway to mitigate stress. Although the function of Hri in regulating globin translation is well established, its role in Atf4 signaling in erythroid precursors is not known. Here, we report the role of the Hri-activated Atf4 signaling pathway in reducing oxidative stress and in promoting erythroid differentiation during erythropoiesis. On acute oxidative stress, Hri−/−erythroblasts suffered from increased levels of reactive oxygen species (ROS) and apoptosis. During chronic iron deficiency in vivo, Hri is necessary both to reduce oxidative stress and to promote erythroid differentiation. Hri−/−mice developed ineffective erythropoiesis during iron deficiency with inhibition of differentiation at the basophilic erythroblast stage. This inhibition is recapitulated during ex vivo differentiation of Hri−/−fetal liver erythroid progenitors. Importantly, the Hri-eIF2αP-Atf4 pathway was activated and required for erythroid differentiation. We further demonstrate the potential of modulating Hri-eIF2αP-Atf4 signaling with chemical compounds as pharmaceutical therapies for β-thalassemia.

We have reported previously that the hepatic heme-regulated inhibitor (HRI)-eukaryotic initiation factor 2α (eIF2α) kinase is activated in acute heme-deficient states, resulting in translational shut-off of global hepatic protein synthesis, including phenobarbital (PB)-mediated induction of CYP2B enzymes in rats. These findings revealed that heme regulates hepatic CYP2B synthesis at the translational level via HRI. As a proof of concept, we have now employed a genetic HRI-knockout (KO) mouse hepatocyte model. In HRI-KO hepatocytes, PB-mediated CYP2B protein induction is no longer regulated by hepatic heme availability and proceeds undeterred even after acute hepatic heme depletion. It is noteworthy that genetic ablation of HRI led to a small albeit significant elevation of basal hepatic endoplasmic reticulum (ER) stress as revealed by the activation of ER stress-inducible RNA-dependent protein kinase-like ER-integral (PERK) eIF2α-kinase, and induction of hepatic protein ubiquitination and ER chaperones Grp78 and Grp94. Such ER stress was further augmented after PB-mediated hepatic protein induction. These findings suggest that HRI normally modulates the basal hepatic ER stress tone. Furthermore, because HRI exists in both human and rat liver in its heme-sensitive form and is inducible by cytochrome P450 inducers such as PB, these findings are clinically relevant to acute heme-deficient states, such as the acute hepatic porphyrias. Activation of this exquisitely sensitive heme sensor would normally protect cells by safeguarding cellular energy and nutrients during acute heme deficiency. However, similar HRI activation in genetically predisposed persons could lead to global translational arrest of physiologically relevant enzymes and proteins, resulting in the severe and often fatal clinical symptoms of the acute hepatic porphyrias.

Erythroid terminal differentiation (ETD) entails cell divisions coupled to decreasing cell size. The tight link between the number of cell divisions and red cell size is apparent in nutritional deficiencies or genetic variants in which fewer cycles result in larger red cells. Here we investigated novel EpoR functions, finding that EpoR signaling disrupts the relationship between cell cycle number and cell size, simultaneously promoting rapid cycling and the formation of larger red cells.

Background:

No relevant conflicts of interest to declare.

The 'MINO' (mammary intraepithelial neoplasia outgrowth) mouse model of ductal carcinoma in situ(DCIS) consists of six lines with distinct morphologic phenotypes and behavior, each meeting experimentally defined criteria for 'precancer'. Specifically, these lines grow orthotopically in cleared mammary fat pads and consistently progress to an invasive phenotype that is capable of ectopic growth. Transition to carcinoma has a consistent latency for each line, and three of the lines also exhibit pulmonary metastatic potential. Gland cleared orthotopic transplanted precancer MINO tissues were analyzed by bacterial artifical chromosome and oligo array comparative genomic hybridization, microsatellite PCR, and telomerase repeat amplification assay. MINO cells were dissociated and cultured in three dimensional culture and transplanted in syngeneic gland cleared mammary fat pads. Comparative genomic hybridization shows that the precancer and invasive tumors are genetically stable, with low level changes including whole chromosome gains in some lines. No changes are associated with progression, although spontaneous focal amplifications and deletions were detected occasionally. Microsatellite analysis shows a low frequency of alterations that are predominantly permanent within a MINO line. Telomerase activity is increased in both the MINO and the derived tumors when compared with normal mouse mammary gland. Dissociation of the precancer lesion cells and three dimensional 'spheroid' culture of single cells reveals a bipotential for myoepithelial and luminal differentiation and the formation of unique three-dimensional 'MINOspheres'. These MINOspheres exhibit features that are intermediate between spheroids that are derived from normal and carcinoma cells. Transplantation of a single cell derived MINOsphere recapitulates the outgrowth of the precancer morphology and progression to carcinoma. These data establish a precancer 'stem' cell that is capable of self-renewal and multilineage differentiation as the origin of invasive cancer. Within the context of this model, these cells have programmed potential for latency and metastasis that does not appear to require sequential genetic 'hits' for transformation.

The aim of this study was to identify factors related to muscle tension in patients with major depressive disorder (MDD) with comorbid anxiety and migraine.

ABSTRACTDiarrhea in children is often caused by enteropathogen infections that might benefit from early empirical antibiotic therapy. However, when the definition of the pathogen requires sophisticated laboratory studies, the etiology of enteritis is not known early in illness. Empirical therapy may be dangerous if the child is infected with a Shiga toxin-producing Escherichia coli(STEC) strain because antimicrobials may increase Shiga toxin (Stx) release, resulting in increased risk of microangiopathic hemolytic anemia with acute renal failure (hemolytic-uremic syndrome [HUS]) and death. There is a need for antimicrobials that would be effective against multiple bacterial enteropathogens yet not induce Stx release or increase the risk of HUS. Rifaximin has been evaluated in adults for treatment of bacterial enteritis and has a good record for safety and efficacy, but it has not been evaluated extensively in children with gastroenteritis. We therefore evaluated rifaximin's potential for phage induction, drug-induced bacteriolysis, and toxin release in 57 STEC strains (26 O157 and 31 non-O157 strains). Growth in ciprofloxacin, a known Stx phage inducer, caused bacteriolysis and release of toxin in 25/26 (96%) O157 strains and 15/31 (48%) non-O157 strains. In contrast, rifaximin did not induce phage replication or lysis in any strain. Toxin release in the presence of rifaximin was not different from release in the absence of antibiotic. Rifaximin, unlike many antibiotics used to treat pediatric gastroenteritis, does not induce phage-mediated bacteriolysis and Stx release.

During erythroid differentiation and maturation, it is critical that the 3 components of hemoglobin, a-globin, ß-globin, and heme, are made in proper stoichiometry to form stable hemoglobin. Heme-regulated translation mediated by the heme-regulated inhibitor kinase (HRI) provides one major mechanism that ensures balanced synthesis of globins and heme. HRI phosphorylates the a-subunit of eukaryotic translational initiation factor 2 (eIF2a) in heme deficiency, thereby inhibiting protein synthesis globally. In this manner, HRI serves as a feedback inhibitor of globin synthesis by sensing the intracellular concentration of heme through its heme-binding domains. HRI is essential not only for the translational regulation of globins, but also for the survival of erythroid precursors in iron deficiency. Recently, the protective function of HRI has also been demonstrated in murine models of erythropoietic protoporphyria and ß-thalassemia. In these 3 anemias, HRI is essential in determining red blood cell size, number, and hemoglobin content per cell. Translational regulation by HRI is critical to reduce excess synthesis of globin proteins or heme under nonoptimal disease states, and thus reduces the severity of these diseases. The protective role of HRI may be more common among red cell disorders.

The purpose of the study was to investigate the morphologic changes of distraction osteogenesis performed on the mandible in growing minipigs.