Genetic interrogation of replicative senescence uncovers a dual role for USP28 in coordinating the p53 and GATA4 branches of the senescence program.

Senescence is a terminal differentiation program that halts the growth of damaged cells and must be circumvented for cancer to arise. Here we describe a panel of genetic screens to identify genes required for replicative senescence. We uncover a role in senescence for the potent tumor suppressor and ATM substrate USP28. USP28 controls activation of both the TP53 branch and the GATA4/NFkB branch that controls the senescence-associated secretory phenotype (SASP). These results suggest a role for ubiquitination in senescence and imply a common node downstream from ATM that links the TP53 and GATA4 branches of the senescence response.

Ultrasound findings of acute pancreatitis in children.

BACKGROUND: Studies systematically documenting US findings in children with acute pancreatitis are limited. Pancreas duct dilation is described as the most reliable finding of acute pancreatitis but this has not been rigorously examined in children. OBJECTIVE: To systematically document US findings in children with acute pancreatitis and to define interobserver agreement on those findings. MATERIALS AND METHODS: In this cross-sectional study we retrospectively reviewed images for all pediatric patients <18 years of age who had been prospectively enrolled in a registry of patients with index admissions for acute pancreatitis between March 2013 and July 2020. Two blinded observers (R1, R2) reviewed the first transabdominal US examination performed within 2 weeks of the pancreatitis attack for each patient. RESULTS: In 141 children, US was performed at a median of 1 day (interquartile range [IQR]: 0, 1) following acute attack. Thirty-three (23%, R1) and 38 (27%, R2) children had no abnormal findings on US. Peripancreatic edema was the most frequent finding documented by both reviewers (63% R1, 54% R2). The pancreatic duct was visible in only 35% of the children and was dilated in only 12% (R1) and 14% (R2). There was substantial to almost-perfect agreement between reviewers on findings of acute pancreatitis (κ=0.62-1), including duct visibility. CONCLUSION: Peripancreatic edema was the most frequently identified finding in children with acute pancreatitis, present in up to 63%, with almost perfect interobserver agreement. Duct dilation, cited in the literature as a reliable finding of acute pancreatitis, was rarely identified in our sample.

ß-Thalassemia mutations in Western India: outcome of prenatal diagnosis in a hemoglobinopathies project.

Prenatal diagnosis (PND) is one of the most cost effective preventive methods, but it is available only in the large cities of India. Therefore, we initiated a program that offers PND and allows us to determine the prevalence of various mutations. Pregnant females (n = 111,426) were screened for hemoglobinopathies using complete blood count (CBC) and high performance liquid chromatography (HPLC). If the female had a hemoglobinopathy, her husband was then tested. If hemoglobinopathies were seen in both partners, a genetic mutation study was performed on the couple. Fetal samples were obtained by either chorionic villus sampling (CVS) in 70.6% or amniocentesis in 29.4%. The study included 282 couples. IVS-I-5 (G > C) was the most common mutation in all castes except in the Sindhis and Lohanas, where the 619 bp deletion was the most common. Prenatal testing was informative in 97.9% of the couples. A significant number of couples (41.0%) underwent PND during their first pregnancy. Seven patients with ß-thalassemia (ß-thal) trait had normal Hb A2 levels. The Hb A2 and Hb F values varied significantly (p < 0.0001 and 0.0082, respectively) among mutations associated with ß-thal. The IVS-I-5, 619 bp deletion, codons 41/42 (-CTTT), codons 8/9 (+G) and IVS-I-1 (G > T or G > A), were present in 81.0% of the couples tested. ß-Thalassemia mutation frequency varied among the different castes, underlining the need for evolving a testing strategy that considers the caste system. Targeting antenatal clinics could also prove to be a most cost effective way of preventing hemoglobinopathies.

Evidence for a functional role of the molecular chaperone clusterin in amyloidotic cardiomyopathy.

Molecular chaperones, including the extracellular protein clusterin (CLU), play a significant role in maintaining proteostasis; they have a unique capacity to bind and stabilize non-native protein conformations, prevent aggregation, and keep proteins in a soluble folding-competent state. In this study, we investigated amyloid-infiltrated cardiac tissue for the presence of CLU and measured serum levels of CLU in patients with and without amyloidotic cardiomyopathy (CMP). Cardiac tissues containing amyloid deposits composed of either transthyretin (TTR) or Ig light chain from nine patients with amyloidotic CMP were examined for the presence of CLU using immunohistochemical techniques. CLU staining coincided with the extracellular myocardial amyloid deposits in tissues from patients with familial TTR, senile systemic, and Ig light chain amyloidosis. The association of CLU with cardiac amyloid deposits was confirmed by immunogold electron microscopy. Serum concentrations of CLU were measured in familial TTR, senile systemic, and Ig light chain amyloidosis patient groups and compared with both age-matched healthy controls and with patients with CMP unrelated to amyloid disease. Subset analysis of disease cohorts, based on cardiac involvement, indicated that decreased serum CLU concentrations were associated with amyloidotic CMP. Taken together, these results suggest that CLU may play a pathogenetic role in TTR and Ig light chain amyloidoses and amyloidotic CMP.

A GATA4-regulated secretory program suppresses tumors through recruitment of cytotoxic CD8 T cells.

The GATA4 transcription factor acts as a master regulator of development of multiple tissues. GATA4 also acts in a distinct capacity to control a stress-inducible pro-inflammatory secretory program that is associated with senescence, a potent tumor suppression mechanism, but also operates in non-senescent contexts such as tumorigenesis. This secretory pathway is composed of chemokines, cytokines, growth factors, and proteases. Since GATA4 is deleted or epigenetically silenced in cancer, here we examine the role of GATA4 in tumorigenesis in mouse models through both loss-of-function and overexpression experiments. We find that GATA4 promotes non-cell autonomous tumor suppression in multiple model systems. Mechanistically, we show that Gata4-dependent tumor suppression requires cytotoxic CD8 T cells and partially requires the secreted chemokine CCL2. Analysis of transcriptome data in human tumors reveals reduced lymphocyte infiltration in GATA4-deficient tumors, consistent with our murine data. Notably, activation of the GATA4-dependent secretory program combined with an anti-PD-1 antibody robustly abrogates tumor growth in vivo.

The adaptive immune system is a major driver of selection for tumor suppressor gene inactivation.

During tumorigenesis, tumors must evolve to evade the immune system and do so by disrupting the genes involved in antigen processing and presentation or up-regulating inhibitory immune checkpoint genes. We performed in vivo CRISPR screens in syngeneic mouse tumor models to examine requirements for tumorigenesis both with and without adaptive immune selective pressure. In each tumor type tested, we found a marked enrichment for the loss of tumor suppressor genes (TSGs) in the presence of an adaptive immune system relative to immunocompromised mice. Nearly one-third of TSGs showed preferential enrichment, often in a cancer- and tissue-specific manner. These results suggest that clonal selection of recurrent mutations found in cancer is driven largely by the tumor's requirement to avoid the adaptive immune system.

The critical role of the constant region in thermal stability and aggregation of amyloidogenic immunoglobulin light chain.

Light chain (LC) amyloidosis (AL) is a fatal disease in which immunoglobulin LC deposit as fibrils. Although the LC amyloid-forming propensity is attributed primarily to the variable region, fibrils also contain full-length LC comprised of variable-joining (V(L)) and constant (C(L)) regions. To assess the role of C(L) in fibrillogenesis, we compared the thermal stability of full-length LC and corresponding V(L) and C(L) fragments. Protein unfolding and aggregation were monitored by circular dichroism and light scattering. A full-length λ6 LC purified from urine of a patient with AL amyloidosis showed irreversible unfolding coupled to aggregation. The transition temperature decreased at slower heating rates, indicating kinetic effects. Next, we studied five recombinant λ6 proteins: full-length amyloidogenic LC, its V(L), germline LC, germline V(L), and C(L). Amyloidogenic and germline proteins showed similar rank order of stability, V(L) < LC < C(L); hence, in the full-length LC, V(L) destabilizes C(L). Amyloidogenic proteins were less stable than their germline counterparts, suggesting that reduction in V(L) stability destabilizes the full-length LC. Thermal unfolding of the full-length amyloidogenic and germline LC required high activation energy and involved irreversible aggregation, yet the unfolding of the isolated V(L) and C(L) fragments was partially reversible. Therefore, compared to their fragments, full-length LCs are more likely to initiate aggregation during unfolding and provide a template for the V(L) deposition. The kinetic barrier for this aggregation is regulated by the stability of the V(L) region. This represents a paradigm shift in AL fibrillogenesis and suggests C(L) region as a potential therapeutic target.

Decreased waiting periods in a public pregnancy termination clinic.

BACKGROUND: In our public hospital, first-trimester pregnancy termination historically had been performed in an operating room by suction curettage on a separate day following the initial clinic visit. To increase efficiency, we instituted three changes over a 2-year period: (a) pregnancy termination procedures were relocated to the outpatient area; (b) same-day service was initiated; and (c) manual vacuum aspiration was introduced. Our primary objective was to assess the effects of these changes on the waiting period in days from the intake visit to the day of termination procedure. Our secondary objectives included assessing any decrease in gestational age at the time of procedure, increases in the numbers of procedures at <9 weeks, the numbers of procedures per session and the proportion done on the day of intake. METHODS: This is a retrospective cross-sectional review of the clinical records of patients who requested pregnancy termination. Data were obtained on 625 patients who underwent a surgical termination of pregnancy from February 1, 2004, to January 31, 2006. RESULTS: The waiting period decreased from 20.3 to 3.6 days (p<.01), and mean gestational age at termination decreased from 11 to 9 weeks (p<.01). The proportion at <9 weeks' gestation increased from 1.7% to 40% (p<.01). The number of procedures per session increased by 52.7% (p<.01). The percentage of same-day procedures increased from 7% to 62%. CONCLUSION: We improved efficiency of care by reducing the waiting period and terminating pregnancies earlier in gestation with manual equipment.

Staphylococcus Alpha-Toxin Action on the Rabbit Iris: Toxic Effects and Their Inhibition.

PURPOSE: Staphylococcus aureus infection of the anterior chamber can occur after cataract surgery, causing inflammation and extensive damage to the iris. Alpha-toxin, the most potent S. aureus corneal toxin, was tested as a possible mediator of damage to the iris, and alpha-toxin anti-serum and a chemical toxin inhibitor were tested as potential pathology-reducing agents. METHODS: The hemolytic activity of alpha-toxin and its inhibition by a chemical inhibitor or anti-serum were quantified in vitro. Purified alpha-toxin, heat-inactivated toxin, or alpha-toxin plus normal serum, alpha-toxin anti-serum, or the chemical inhibitor, methyl-ß-cyclodextrin-cholesterol (CD-cholesterol), was injected into the rabbit anterior chamber. Pathological changes were photographed, quantified by slit-lamp examination (SLE) scoring, and further documented by histopathological analysis. RESULTS: At five hours post-injection, eyes injected with alpha-toxin or heat-inactivated toxin had a mean SLE score of 7.3 ± 0.59 or 0.84 ± 0.19, respectively. Active toxin caused moderate to severe iris edema, severe erosion of the iris, and mild to moderate fibrin accumulation in the anterior chamber. Alpha-toxin plus anti-serum or CD-cholesterol, in contrast to alpha-toxin alone, caused less iris edema and epithelium sloughing as well as significantly lower SLE scores than eyes receiving alpha-toxin alone (p ≤ 0.019). CONCLUSION: Alpha-toxin caused extensive iris damage and inflammation, and either anti-alpha-toxin anti-serum or CD-cholesterol was able to significantly reduce toxin-mediated damage and inflammation.

Nasopharyngeal carriage of methicillin-resistant Staphylococcus aureus: incidence and outcomes in pregnant women.

CONTEXT: Infections due to methicillin-resistant Staphylococcus aureus (MRSA), especially community-acquired MRSA, have increased substantially during the past decade. The optimal protocols for screening patients, particularly during pregnancy, have not been determined. OBJECTIVES: To determine the incidence of nasopharyngeal carriage of MRSA in pregnancy as well as whether there was a correlation between positive maternal screening test results and an increased risk of adverse maternal or neonatal outcomes, including neonatal carriage of MRSA. METHODS: The authors conducted a retrospective review of medical records from Rockford Memorial Hospital in Illinois between December 14, 2007, and July 14, 2008. All patients, who were pregnant women admitted to the hospital, and their newborns had nasopharyngeal swabs collected for MRSA detection. Numbers of neonatal intensive care unit admissions and results of neonatal sepsis evaluations were noted. Maternal postoperative infections and anesthesia-related complications were noted and compared to those of control patients. Apgar scores at birth were compared with those of a control group. RESULTS: Of 1,045 patients who were tested, 31 patients (2.9%) had positive results for MRSA. By comparison, the hospital-wide MRSA prevalence for this period was 7.9% (569 positive results of 7,206 patients tested). This prevalence was substantially higher than that noted for the study population. Twenty-three of the 31 patients (74%) delivered at our institution and thus comprised the study group. A control group comprised 46 patients with negative results of MRSA screening. No positive results of neonatal MRSA screening tests were noted in either group, and no statistically significant difference between the 2 groups existed in 5-minute Apgar scores, neonatal intensive care unit admissions, or neonatal sepsis evaluations. Positive MRSA-screening test results were associated with a statistically significant decrease in the provision of regional anesthesia to the pregnant women (P=.05). CONCLUSION: Maternal nasopharyngeal carriage of MRSA was not associated with adverse maternal or neonatal outcomes, including neonatal MRSA carriage. Regional anesthesia was provided less frequently to MRSA-positive individuals. Further studies in larger groups of patients are needed to help determine the optimal management of MRSA-positive patients during pregnancy.

Transient inhibition of primary motor cortex suppresses hand muscle responses during a reactive reach to grasp.

Rapid balance reactions such as compensatory reach to grasp represent important response strategies following unexpected loss of balance. While it has been assumed that early corrective actions arise from subcortical networks, recent research has prompted speculation about the potential role of cortical involvement. With reach to grasp reactions there is evidence of parallels in the control of perturbation-evoked reaching versus rapid voluntary reaching. However, the potential role of cortical involvement in such rapid balance reactions remains speculative. To test if cortical motor regions are involved we used continuous theta burst stimulation (cTBS) to temporarily suppress the hand area of primary motor cortex (M1) in participants involved in two reaching conditions: (1) rapid compensatory perturbation-evoked reach to grasp and (2) voluntary reach to grasp in response to an auditory cue. We hypothesized that following cTBS to the left M1 hand area we would find diminished EMG responses in the reaching (right) hand for both compensatory and voluntary movements. To isolate balance reactions to the upper limb participants were seated in an elevated tilt-chair with a stable handle positioned in front of their right shoulder. The chair was held vertical by a magnet and triggered to fall backward randomly. To regain balance, participants were instructed to reach for the handle as quickly as possible with the right hand upon chair release. Intermixed with perturbation trials, participants were also required to reach for the same handle but in response to an auditory tone. Muscle activity was recorded from several muscles of the right arm/hand using electromyography. As expected, movement time and muscle onsets were much faster following perturbation versus auditory-cued reaching. The novel finding from our study was the reduced amplitude of hand muscle activity post-cTBS for both perturbation-cued and auditory-cued reaches. Moreover, this reduction was specific to the cTBS-targeted hand with no effect on remaining arm muscles. These findings support the idea that cortical networks contribute to both volitional and perturbation-evoked reaches and provide evidence for M1involvement in driving early arm responses toward a target following sudden loss of balance.