The protein phosphatase-2A subunit PR130 is involved in the formation of cytotoxic protein aggregates in pancreatic ductal adenocarcinoma cells.

As a major source of cellular serine and threonine phosphatase activity, protein phosphatase-2A (PP2A) modulates signaling pathways in health and disease. PP2A complexes consist of catalytic, scaffolding, and B-type subunits. Seventeen PP2A B-type subunits direct PP2A complexes to selected substrates. It is ill-defined how PP2A B-type subunits determine the growth and drug responsiveness of tumor cells. Pancreatic ductal adenocarcinoma (PDAC) is a disease with poor prognosis. We analyzed the responses of murine and human mesenchymal and epithelial PDAC cells to the specific PP2A inhibitor phendione. We assessed protein levels by immunoblot and proteomics and cell fate by flow cytometry, confocal microscopy, and genetic manipulation. We show that murine mesenchymal PDAC cells express significantly higher levels of the PP2A B-type subunit PR130 than epithelial PDAC cells. This overexpression of PR130 is associated with a dependency of such metastasis-prone cells on the catalytic activity of PP2A. Phendione induces apoptosis and an accumulation of cytotoxic protein aggregates in murine mesenchymal and human PDAC cells. These processes occur independently of the frequently mutated tumor suppressor p53. Proteomic analyses reveal that phendione upregulates the chaperone HSP70 in mesenchymal PDAC cells. Inhibition of HSP70 promotes phendione-induced apoptosis and phendione promotes a proteasomal degradation of PR130. Genetic elimination of PR130 sensitizes murine and human PDAC cells to phendione-induced apoptosis and protein aggregate formation. These data suggest that the PP2A-PR130 complex dephosphorylates and thereby prevents the aggregation of proteins in tumor cells.

Increased Mortality in Patients Transferred to a Level 1 Trauma Center with Blunt and Penetrating Extremity Vascular Injuries.

BACKGROUND: Trauma care depends on a complex transfer system to ensure timely and adequate management at major trauma centers. Patient outcomes depend on the reliability of triage in local or community hospitals and access to tertiary or quaternary trauma institutions. Patients with polytrauma, extremity trauma, or vascular injuries require multidisciplinary management at trauma hospitals. Our study investigated outcomes in this population at a level one trauma center in San Bernardino County, the largest geographic county in the contiguous United States. METHODS: We conducted a retrospective review of all patients with extremity trauma who presented to a single level 1 trauma center over 10 years. The cohort was divided into following two groups: 1. transferred from another medical center for a higher level of care or 2. those who directly presented. Overall, 19,417 patients were identified, with 15,317 patients presenting directly and 3,830 patients transferred from an outside hospital. Extremity of vascular injuries was observed in 268 patients. Demographic data were ascertained, including the injury severity score, mechanism of injury, response level, arrival method, tertiary center emergency department disposition, and presence of vascular injury in the upper or lower extremities. Univariate and multivariate analyses were performed to assess patient mortality. RESULTS: A total of 268 patients with vascular injuries were analyzed, including 207 nontransferred and 61 transferred patients. In the univariate analysis, injury severity score means were compared at 11.4 in nontransferred patients versus 8.4 in transferred (P < 0.001), 50% of blunt injury in the nontransferred group, and 28% in the transferred group (P < 0.001); in-hospital mortality was 4% in nontransferred patients versus 28% in the transferred group (P < 0.001). Multivariate logistic regression demonstrated that mortality is 8 times more likely if a patient with vascular extremity injuries is transferred from an outside hospital. A 10% mortality rate was observed in patients without blood transfusion within 4 hr of arrival to the trauma center and 3% mortality in transferred patients transfused blood. CONCLUSIONS: Extremity trauma with vascular injury can be lethal if managed appropriately. Patients transferred to our level 1 trauma center had a substantial increase in mortality compared with nontransferred patients. Furthermore, the transfer distance was associated with increased mortality. Further research is required to address this vulnerable patient population.

The epigenetic modifier HDAC2 and the checkpoint kinase ATM determine the responses of microsatellite instable colorectal cancer cells to 5-fluorouracil.

The epigenetic modifier histone deacetylase-2 (HDAC2) is frequently dysregulated in colon cancer cells. Microsatellite instability (MSI), an unfaithful replication of DNA at nucleotide repeats, occurs in about 15% of human colon tumors. MSI promotes a genetic frameshift and consequently a loss of HDAC2 in up to 43% of these tumors. We show that long-term and short-term cultures of colorectal cancers with MSI contain subpopulations of cells lacking HDAC2. These can be isolated as single cell-derived, proliferating populations. Xenografted patient-derived colon cancer tissues with MSI also show variable patterns of HDAC2 expression in mice. HDAC2-positive and HDAC2-negative RKO cells respond similarly to pharmacological inhibitors of the class I HDACs HDAC1/HDAC2/HDAC3. In contrast to this similarity, HDAC2-negative and HDAC2-positive RKO cells undergo differential cell cycle arrest and apoptosis induction in response to the frequently used chemotherapeutic 5-fluorouracil, which becomes incorporated into and damages RNA and DNA. 5-fluorouracil causes an enrichment of HDAC2-negative RKO cells in vitro and in a subset of primary colorectal tumors in mice. 5-fluorouracil induces the phosphorylation of KAP1, a target of the checkpoint kinase ataxia-telangiectasia mutated (ATM), stronger in HDAC2-negative cells than in their HDAC2-positive counterparts. Pharmacological inhibition of ATM sensitizes RKO cells to cytotoxic effects of 5-fluorouracil. These findings demonstrate that HDAC2 and ATM modulate the responses of colorectal cancer cells towards 5-FU.

Specialize and Divide (Twice): Functions of Three Aurora Kinase Homologs in Mammalian Oocyte Meiotic Maturation.

The aurora kinases (AURKs) comprise an evolutionarily conserved family of serine/threonine kinases involved in mitosis and meiosis. While most mitotic cells express two AURK isoforms (AURKA and AURKB), mammalian germ cells also express a third, AURKC. Although much is known about the functions of the kinases in mitosis, less is known about how the three isoforms function to coordinate meiosis. This review is aimed at describing what is known about the three isoforms in female meiosis, the similarities and differences between kinase functions, and speculates as to why mammalian germ cells require expression of three AURKs instead of two.

Improving Pleasure and Motivation in Schizophrenia: A Randomized Controlled Clinical Trial.

BACKGROUND: Negative symptoms are frequent in patients with schizophrenia and are associated with marked impairments in social functioning. The efficacy of drug-based treatments and psychological interventions on primary negative symptoms remains limited. The Positive Emotions Programme for Schizophrenia (PEPS) is designed to improve pleasure and motivation in schizophrenia patients by targeting emotion regulation and cognitive skills relevant to apathy and anhedonia. The main hypothesis of this study is that patients who attend 8 one-hour sessions of PEPS and treatment as usual (TAU) will have lower total apathy-avolition and anhedonia-asociality composite scores on the Scale for the Assessment of Negative Symptoms (SANS) than patients who attend only TAU. METHODS: Eighty participants diagnosed with schizophrenia or schizoaffective disorder were randomized to receive either TAU or PEPS + TAU. The participants were assessed by independent evaluators before randomization (T0), in a post-test after 8 weeks of treatment (T1) and at a 6-month follow-up (T2). RESULTS: The post-test results and 6-month follow-up assessments according to an intention-to-treat analysis showed that the apathy and anhedonia composite scores on the SANS indicated statistically greater clinical improvements in PEPS participants than in non-PEPS participants. In the post-test, anhedonia but not apathy was significantly improved, thus favouring the PEPS condition. These results were sustained at the 6-month follow-up. CONCLUSIONS: PEPS is an effective intervention to reduce anhedonia in schizophrenia. PEPS is a short, easy-to-use, group-based, freely available intervention that is easy to implement in a variety of environments (ClinicalTrials.gov ID: NCT02593058).

The chromosomal basis of meiotic acentrosomal spindle assembly and function in oocytes.

Several aspects of meiosis are impacted by the absence of centrosomes in oocytes. Here, we review four aspects of meiosis I that are significantly affected by the absence of centrosomes in oocyte spindles. One, microtubules tend to assemble around the chromosomes. Two, the organization of these microtubules into a bipolar spindle is directed by the chromosomes. Three, chromosome bi-orientation and attachment to microtubules from the correct pole require modification of the mechanisms used in mitotic cells. Four, chromosome movement to the poles at anaphase cannot rely on polar anchoring of spindle microtubules by centrosomes. Overall, the chromosomes are more active participants during acentrosomal spindle assembly in oocytes, compared to mitotic and male meiotic divisions where centrosomes are present. The chromosomes are endowed with information that can direct the meiotic divisions and dictate their own behavior in oocytes. Processes beyond those known from mitosis appear to be required for their bi-orientation at meiosis I. As mitosis occurs without centrosomes in many systems other than oocytes, including all plants, the concepts discussed here may not be limited to oocytes. The study of meiosis in oocytes has revealed mechanisms that are operating in mitosis and will probably continue to do so.

Haspin kinase regulates microtubule-organizing center clustering and stability through Aurora kinase C in mouse oocytes.

Meiotic oocytes lack classic centrosomes and, therefore, bipolar spindle assembly depends on clustering of acentriolar microtubule-organizing centers (MTOCs) into two poles. However, the molecular mechanism regulating MTOC assembly into two poles is not fully understood. The kinase haspin (also known as GSG2) is required to regulate Aurora kinase C (AURKC) localization at chromosomes during meiosis I. Here, we show that inhibition of haspin perturbed MTOC clustering into two poles and the stability of the clustered MTOCs. Furthermore, we show that AURKC localizes to MTOCs in mouse oocytes. Inhibition of haspin perturbed the localization of AURKC at MTOCs, and overexpression of AURKC rescued the MTOC-clustering defects in haspin-inhibited oocytes. Taken together, our data uncover a role for haspin as a regulator of bipolar spindle assembly by regulating AURKC function at acentriolar MTOCs in oocytes.

Identification and characterization of Aurora kinase B and C variants associated with maternal aneuploidy.

STUDY QUESTION: Are single nucleotide variants (SNVs) in Aurora kinases B and C (AURKB, AURKC) associated with risk of aneuploid conception? SUMMARY ANSWER: Two SNVs were found in patients with extreme aneuploid concepti rates with respect to their age; one variant, AURKC p.I79V, is benign, while another, AURKB p.L39P, is a potential gain-of-function mutant with increased efficiency in promoting chromosome alignment. WHAT IS KNOWN ALREADY: Maternal age does not always predict aneuploidy risk, and rare gene variants can be drivers of disease. The AURKB and AURKC regulate chromosome segregation, and are associated with reproductive impairments in mouse and human. STUDY DESIGN, SIZE, DURATION: An extreme phenotype sample selection scheme was performed for variant discovery. Ninety-six DNA samples were from young patients with higher than average embryonic aneuploidy rates and an additional 96 DNA samples were from older patients with lower than average aneuploidy rates. PARTICIPANTS/MATERIALS, SETTING, METHODS: Using the192 DNA samples, the coding regions of AURKB and AURKC were sequenced using next generation sequencing. To assess biological significance, we expressed complementary RNA encoding the human variants in mouse oocytes. Assays such as determining subcellular localization and assessing catalytic activity were performed to determine alterations in protein function during meiosis. MAIN RESULTS AND THE ROLE OF CHANCE: Ten SNVs were identified using three independent variant-calling methods. Two of the SNVs (AURKB p.L39P and AURKC p.I79V) were non-synonymous and identified by at least two variant-identification methods. The variant encoding AURKC p.I79V, identified in a young woman with a higher than average rate of aneuploid embryos, showed wild-type localization pattern and catalytic activity. On the other hand, the variant encoding AURKB p.L39P, identified in an older woman with lower than average rates of aneuploid embryos, increased the protein's ability to regulate alignment of chromosomes at the metaphase plate. These experiments were repeated three independent times using 2-3 mice for each trial. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Biological significance of the human variants was assessed in an in vitro mouse oocyte model where the variants are over-expressed. Therefore, the human protein may not function identically to the mouse homolog, or the same in mouse oocytes as in human oocytes. Furthermore, supraphysiological expression levels may not accurately reflect endogenous activity. Moreover, the evaluated variants were identified in one patient each, and no trial linking the SNV to pregnancy outcomes was conducted. Finally, the patient aneuploidy rates were established by performing comprehensive chromosome screening in blastocysts, and because of the link between female gamete aneuploidy giving rise to aneuploid embryos, we evaluate the role of the variants in Meiosis I. However, it is possible that the chromosome segregation mistake arose during Meiosis II or in mitosis in the preimplantation embryo. Their implications in human female meiosis and aneuploidy risk remain to be determined. WIDER IMPLICATIONS OF THE FINDINGS: The data provide evidence that gene variants exist in reproductively younger or advanced aged women that are predictive of the risk of producing aneuploid concepti in humans. Furthermore, a single amino acid in the N-terminus of AURKB is a gain-of-function mutant that could be protective of euploidy. STUDY FUNDING/COMPETING INTERESTS: This work was supported by a Research Grant from the American Society of Reproductive Medicine and support from the Charles and Johanna Busch Memorial Fund at Rutgers, the State University of NJ to K.S. and the Foundation for Embryonic Competence, Inc to N.T. The authors declare no conflicts of interest.

Phosphorylation of threonine 3 on histone H3 by haspin kinase is required for meiosis I in mouse oocytes.

Meiosis I (MI), the division that generates haploids, is prone to errors that lead to aneuploidy in females. Haspin is a kinase that phosphorylates histone H3 on threonine 3, thereby recruiting Aurora kinase B (AURKB) and the chromosomal passenger complex (CPC) to kinetochores to regulate mitosis. Haspin and AURKC, an AURKB homolog, are enriched in germ cells, yet their significance in regulating MI is not fully understood. Using inhibitors and overexpression approaches, we show a role for haspin during MI in mouse oocytes. Haspin-perturbed oocytes display abnormalities in chromosome morphology and alignment, improper kinetochore-microtubule attachments at metaphase I and aneuploidy at metaphase II. Unlike in mitosis, kinetochore localization remained intact, whereas the distribution of the CPC along chromosomes was absent. The meiotic defects following haspin inhibition were similar to those observed in oocytes where AURKC was inhibited, suggesting that the correction of microtubule attachments during MI requires AURKC along chromosome arms rather than at kinetochores. Our data implicate haspin as a regulator of the CPC and chromosome segregation during MI, while highlighting important differences in how chromosome segregation is regulated between MI and mitosis.

Positive Emotions Program for Schizophrenia (PEPS): a pilot intervention to reduce anhedonia and apathy.

BACKGROUND: Recent literature has distinguished the negative symptoms associated with a diminished capacity to experience (apathy, anhedonia) from symptoms associated with a limited capacity for expression (emotional blunting, alogia). The apathy-anhedonia syndrome tends to be associated with a poorer prognosis than the symptoms related to diminished expression. The efficacy of drug-based treatments and psychological interventions for these symptoms in schizophrenia remains limited. There is a clear clinical need for new treatments. METHODS: This pilot study tested the feasibility of a program to reduce anhedonia and apathy in schizophrenia and assessed its impact on 37 participants meeting the ICD-10 criteria for schizophrenia or schizoaffective disorders. Participants were pre- and post-tested using the Scale for the Assessment of Negative Symptoms (SANS) and the Calgary Depression Scale for Schizophrenia (CDSS). They took part in eight sessions of the Positive Emotions Program for Schizophrenia (PEPS)--an intervention that teaches participants skills to help overcome defeatist thinking and to increase the anticipation and maintenance of positive emotions. RESULTS: Thirty-one participants completed the program; those who dropped out did not differ from completers. Participation in the program was accompanied by statistically significant reductions in the total scores for Avolition-Apathy and Anhedonia-Asociality on the SANS, with moderate effect sizes. Furthermore, there was a statistically significant reduction of depression on the CDSS, with a large effect size. Emotional blunting and alogia remain stable during the intervention. DISCUSSION: Findings indicate that PEPS is both a feasible intervention and is associated with an apparently specific reduction of anhedonia and apathy. However, these findings are limited by the absence of control group and the fact that the rater was not blind to the treatment objectives. CONCLUSIONS: PEPS is a promising intervention to improve anhedonia and apathy which need to be tested further in a controlled study. TRIAL REGISTRATION NUMBER: ISRCTN registry ISRCTN74048461, registered 18 may 2015.

[New developments in psychiatry]. / Psychiatrie.

In this review of recent therapeutic developments in psychiatry, we will report on three domains where new strategies have been proposed. First we will discuss the concept of neuroprotection in patients at "ultra high risk" to develop psychosis and the encouraging results of a randomised controlled trial comparing the effect of placebo and fish oil. We will then present the impact of metacognition programs which aim at adding some flexibility to thought processes used by patients with psychosis in order to reduce psychotic symptoms. We finally will report on a program of supported employment which was developed in order to help patients find an active place in society.

Women involvement in the informal caregiving field: A perspective review.

The patient recovery process of individual with mental health disorder is reinforced if they are connected with their community and supported by relatives. The literature has shown that caregivers are important, although their roles can lead to alterations in their own health; and women are the most involved in this role. The present review investigated women's involvement in the informal caregiver scientific field. A literature review indicated gender differences; researchers who are women are more interested in this field than men. Even with a good representation of women in this scientific field, the results showed a statistically significant gender difference for the first and second authors, whereas there was no significant gender difference among the last authors. More efforts must be made to recognize the importance of women's involvement in research because they raise a specific important field. Family caregivers are key players in the healthcare system, but to date, there has been little recognition of their enormous contribution. Our results also indicated the informal caregiver role is filled more by women than by men, which creates social inequalities in many domains, especially in opportunities at the professional level. Tailored interventions are required to address the specific needs and issues of family caregivers. A better redistribution of unpaid work, such as informal caregiving, compared to paid work must be made to respect gender in social existence.

The Impact of Computed Tomography Scans on the Management and Wait Times in Perianal Abscess Diagnoses.

Background Diagnosis and management of perianal abscesses (PAA) are based on history and clinical examination. Imaging is not indicated except in complicated cases, as determined by the surgical team. The monetary, ionizing radiation, and resource utilization costs of a computed tomography (CT) scan in the emergency room must be considered when used for diagnostic purposes of PAAs. Methods A retrospective analysis of 129 patients diagnosed with a diagnosis of PAA between 2015-2020 was performed. The primary endpoints included length of stay, CT performed, time from patient presentation to CT, and CT scan completion prior to surgical consultation. Data is reported as n (%) or median (IQR). Results Of the 129 patients diagnosed with PAA, 81 underwent CT, and 48 did not. General surgery was consulted in 88% of cases. There were no statistically significant differences in age (p=0.562), sex (p=0.531), or ethnicity (p=0.356). The median hospitalization time was two days when CT was performed (p=0.001). The median time elapsed from presentation to the emergency department and CT scan performed was 16 hours (p=0.001). CT scans were ordered before the surgical consultation in 65% of cases (p=0.001) and 17% after a surgical consultation was placed (p=0.009). Conclusion Performing CT scans prior to surgical evaluation for the diagnosis of PAA is not a responsible practice. The cost, resources, and radiation exposure must be considered. This study demonstrated that more CT scans are ordered prior to surgical consultation for PAA, resulting in a prolonged wait time in the emergency department.

Integration of a peer practitioner in a hospital unit for patients with psychotic disorders: an exploratory qualitative study.

Introduction: Studies on the integration of peer mental health practitioners (PMHP) in hospitals are sparse, despite significant benefits being reported for patients and professionals. The integration of PMHP requires the consideration of several parameters and a change in the culture of care. This study aims to understand the impact of the integration of a PMHP in a hospital unit caring for patients with psychiatric disorders. Methods: A qualitative content analysis of three focus groups with the interdisciplinarity team were conducted. A consulting PMHP was integrated into the entire research process. Results: Data analysis revealed five main themes: the importance of integration, benefits for patients linked to the identification process, benefits for the team and institution, potentials risks, and perspectives. Discussion: The study was conducted in a hospital setting with patients suffering from severe psychiatric disorders associated with behavioral disturbances. The benefits reported in the results outline the feasibility of PMHP integration in an acute psychiatric care setting. Nevertheless, further formalization of the PMHP role is required to minimize possible areas of tension between respective fields of activity of each professional.

A randomized controlled trial of a targeted support program for informal caregivers in adult psychiatry.

Background: The importance of informal caregivers for persons with severe mental illness has been demonstrated. However, this role may cause a high care burden that considerably affects caregiver health. The Ensemble program is a five-session brief individual intervention designed to support informal caregivers. This trial aimed to assess the efficacy of the program versus SAU (support as usual) for participants with a high care burden. Methods: A single-center randomized controlled trial including 149 participants was conducted. Caregivers in the intervention arm participated in the Ensemble program. The effects of the intervention were assessed using mixed models for repeated measures analysis of variance on improvements in informal caregivers' psychological health status, optimism levels, burden scores, and quality of life at three time points (T0 = pretest; T1 = posttest at 2 months, and T2 = follow-up at 4 months). Results: Analysis of the Global Psychological Index showed no significant effect at the two endpoints in favor of the Ensemble group. However, the Brief Symptom Inventory-Positive Symptom Distress Index was significantly lower at the two-month follow-up. A significant reduction in burden on the Zarit Burden Interview was observed post-intervention, along with an increase in optimism levels on the Life Orientation Test-Revised at follow-up in the Ensemble group. No significant differences were observed in quality of life. Clinical improvements in both psychological health status and burden levels were also identified. Conclusion: The Ensemble program offers an inclusive approach based on a recovery perspective that significantly reduces symptom distress and burden and increases optimism among informal caregivers.Clinical trial registration: https://clinicaltrials.gov/, NCT04020497.

An Evaluation of an Online Training Platform for Teaching Positive Emotions for People With Schizophrenia.

BACKGROUND: The dissemination of new interventions in clinical practice remains challenging. E-learning may provide wide access in various settings and allow tailored learning trajectories and an adapted training pace. This study evaluates an online platform to train professionals to lead the Positive Emotion Program for Schizophrenia (PEPS) for patients with anhedonia. This study aims to test the reception provided by clinicians to the platform and its perceived usefulness and investigate whether e-PEPS training improves knowledge about the facilitation of PEPS. MATERIALS AND METHODS: Participants were recruited through advertisements. All participants provided their informed consent on a registration form and completed two pre-test questionnaires, a knowledge test on negative symptoms in schizophrenia, learning strategies and the partnership relationship, and a test on the ability to savor pleasant moments. After the training, they completed the same questionnaire and an evaluation form of the training and its application in personal and professional life. RESULTS: Two-hundred and ten participants were registered to participate into the study, 185 received the access to the platform, and 101 participants completed the training and the post-test assessments. Satisfaction with training was high. The results showed that the participants significantly improved their knowledge about PEPS and increased the skills taught in their personal repertoire after the training. The training allows most clinicians to plan to lead a PEPS group in the year following training. DISCUSSION: As a result of this study, training has been improved and is now freely available to all interested clinicians.

Development of Early Abdominal Compartment Syndrome Leading to Emergent Decompressive Laparotomy in Full-Thickness Burn Injury.

Burn injuries carry an increased risk of intra-abdominal hypertension and are an independent risk factor for abdominal compartment syndrome (ACS). ACS is most commonly due to large volume resuscitation. The added concern of ACS can complicate resuscitative efforts. Early monitoring for ACS (intra-abdominal pressure > 20 mm Hg with associated new-onset organ dysfunction) and performing prudent decompressive laparotomies are important factors to keep in mind when treating large surface area burn patients. This case report describes the hospitalization of a 60-year-old male who presented with 45% full-thickness (FT) total body surface area (TBSA) and inhalation injury. On arrival to the emergency department (ED), he had received a total of 6 L of intravenous lactate Ringers, and vasopressors were initiated due to hypotension. During the tertiary examination it was noted that there was increased difficulty ventilating the patient, and his abdomen was becoming increasingly distended and tense. His intra-abdominal pressure was measured in the ED and found to be elevated at 32 mm Hg. The findings were suggestive of ACS and a decompressive laparotomy was performed in the ED. Upon entering the abdominal cavity, the abdominal contents extruded through the incision and diffuse venous congestion and gastric distention were noted. Items commonly found in operating rooms (Top-Draper® warmer drape, Kerlix rolls, Jackson-Pratt suction drains, and 3M® Ioban sterile antimicrobial incise drape) were utilized to maintain an open abdomen where abdominal contents could easily be observed and to prevent delay in performing a decompressive laparotomy. Here we describe a patient with 45% FT TBSA and inhalation injuries requiring an emergent decompressive laparotomy for ACS after only 6 L of lactate Ringers were administered. This highlights the importance of early monitoring for ACS and the ease of performing a decompressive laparotomy with commonly found items in the ED and operating rooms.

Bronchopulmonary Fistula Development in an Elderly Male With COVID-19 Infection.

COVID-19 pneumonia can cause a wide range of complications including pneumothorax and empyema. However, in severe cases, it can lead to bronchopulmonary fistula (BPF) formation and a persistent air leak due to a connection between the pleural space and the bronchial tree. We report the case of a 77-year-old man with a history of hypertension, who presented to the emergency department for evaluation of dyspnea. Admission labs were significant for a positive rapid antigen SARS-Cov-2 test and elevated troponin I. A chest x-ray demonstrated patchy interstitial opacification and ground glass appearance bilaterally. Within the first 24 hours of presentation, the patient developed a right-sided spontaneous pneumothorax and had a 14 French pigtail catheter placed. The patient subsequently developed a persistent air leak after chest tube placement and required video-assisted thoracoscopic surgery (VATS) with talc pleurodesis and a 32 French chest tube placement. In this unique case, we describe an elderly patient's experience of bronchopulmonary fistula formation as a complication of COVID-19 pneumonia and the successful management of this complication with VATS.

Oxaliplatin-Induced Senescence in Colorectal Cancer Cells Depends on p14ARF-Mediated Sustained p53 Activation.

Senescence is an important consequence of cytostatic drug-based tumor therapy. Here we analyzed to which degree the anticancer drug oxaliplatin induces cell death, cell cycle arrest, and senescence in colorectal cancer (CRC) cells and elucidated the role of p53. Oxaliplatin treatment resulted in the G2-phase arrest in all CRC lines tested (HCT116p53+/+, HCT116p53-/-, LoVo, SW48 and SW480). Immunoblot analysis showed that within the p53-competent lines p53 and p21CIP1 are activated at early times upon oxaliplatin treatment. However, at later times, only LoVo cells showed sustained activation of the p53/p21CIP1 pathway, accompanied by a strong induction of senescence as measured by senescence-associated ß-Gal staining and induction of senescence-associated secretory phenotype (SASP) factors. Opposite to LoVo, the p53/p21CIP1 response and senescence induction was much weaker in the p53-proficient SW48 and SW480 cells, which was due to deficiency for p14ARF. Thus, among lines studied only LoVo express p14ARF protein and siRNA-mediated knockdown of p14ARF significantly reduced sustained p53/p21CIP1 activation and senescence. Vice versa, ectopic p14ARF expression enhanced oxaliplatin-induced senescence in SW48 and SW480 cells. Our data show that oxaliplatin-induced senescence in CRC cells is dependent on p53 proficiency; however, a significant induction can only be observed upon p14ARF-mediated p53 stabilization.

Age-dependent integrity of the meiotic spindle assembly checkpoint in females requires Aurora kinase B.

A hallmark of advanced maternal age is a significant increase in meiotic chromosome segregation errors, resulting in early miscarriages and congenital disorders. These errors most frequently occur during meiosis I (MI). The spindle assembly checkpoint (SAC) prevents chromosome segregation errors by arresting the cell cycle until proper chromosome alignment is achieved. Unlike in mitosis, the SAC in oocytes is desensitized, allowing chromosome segregation in the presence of improperly aligned chromosomes. Whether SAC integrity further deteriorates with advancing maternal age, and if this decline contributes to increased segregation errors remains a fundamental question. In somatic cells, activation of the SAC depends upon Aurora kinase B (AURKB), which functions to monitor kinetochore-microtubule attachments and recruit SAC regulator proteins. In mice, oocyte-specific deletion of AURKB (Aurkb cKO) results in an increased production of aneuploid metaphase II-arrested eggs and premature age-related infertility. Here, we aimed to understand the cause of the short reproductive lifespan and hypothesized that SAC integrity was compromised. In comparing oocytes from young and sexually mature Aurkb cKO females, we found that SAC integrity becomes compromised rapidly with maternal age. We show that the increased desensitization of the SAC is driven by reduced expression of MAD2, ZW10 and Securin proteins, key contributors to the SAC response pathway. The reduced expression of these proteins is the result of altered protein homeostasis, likely caused by the accumulation of reactive oxygen species. Taken together, our results demonstrate a novel function for AURKB in preserving the female reproductive lifespan possibly by protecting oocytes from oxidative stress.