Tartrate-resistant acid phosphatase-positive cells in the synovial–cartilage junction and bone marrow during the progression of collagen-induced arthritis in adult rats

We investigated the time-course changes in bone destruction in rats with collagen-induced arthritis (CIA). The synovial–cartilage junction (SCJ) and epiphyseal bone marrow of the femoral posteromedial condyle in CIA rats were evaluated histologically and immunohistologically at 2, 3, 4, 6, and 8 weeks after sensitization. Two weeks after sensitization, tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells formed resorption lacunae on the lateral side of the cortical bone under the SCJ. No resorption lacunae were observed in bone marrow. Three weeks after sensitization, resorption lacunae on the lateral side of the cortical bone expanded, but no bone marrow invasion by pannus was observed. In bone marrow, many TRAP-positive multinuclear cells appeared and formed resorption lacunae in subchondral bone. Four weeks after sensitization, cortical bone was destroyed, and pannus had invaded the bone marrow. After six weeks, trabecular bone and subchondral bone plate were extensively resorbed by TRAP-positive cells. Bone destruction in CIA began with the appearance of TRAP-positive cells on the lateral side of the cortical bone under the SCJ, followed by the TRAP-positive multinuclear cells in bone marrow, which were morphologically unconnected to the SCJ lesions. These histological findings suggested that bone destruction in the early stage of arthritis occurred in two anatomically different regions.     

M-phase kinases induce phospho-dependent ubiquitination of somatic Wee1 by SCFbeta-TrCP

Wee1, the Cdc2 inhibitory kinase, needs to be down-regulated at the onset of mitosis to ensure rapid activation of Cdc2. Previously, we have shown that human somatic Wee1 (Wee1A) is down-regulated both by protein phosphorylation and degradation, but the underlying mechanisms had not been elucidated. In the present study, we have identified the beta-transducin repeat-containing protein 1/2 (beta-TrCP1/2) F-box protein-containing SKP1/Cul1/F-box protein (SCF) complex (SCF(beta-TrCP1/2)) as an E3 ubiquitin ligase for Wee1A ubiquitination. Although Wee1A lacks a consensus DS(p)GXXS(p) phospho-dependent binding motif for beta-TrCP, recognition of Wee1A by beta-TrCP depended on phosphorylation, and two serine residues in Wee1A, S53 and S123, were found to be the most important phosphorylation sites for beta-TrCP recognition. We have found also that the major M-phase kinases polo-like kinase 1 (Plk1) and Cdc2 are responsible for the phosphorylation of S53 and S123, respectively, and that in each case phosphorylation generates an unconventional phospho-degron (signal for degradation) that can be recognized by beta-TrCP. Phosphorylation of Wee1A by these kinases cooperatively stimulated the recognition and ubiquitination of Wee1A by SCF(beta-TrCP1/2) in vitro. Mutation of these residues or depletion of beta-TrCP by small-interfering RNA treatment increased the stability of Wee1A in HeLa cells. Moreover, our analysis indicates that beta-TrCP-dependent degradation of Wee1A is important for the normal onset of M-phase in vivo. These results also establish the existence of a feedback loop between Cdc2 and Wee1A in somatic cells that depends on ubiquitination and protein degradation and ensures the rapid activation of Cdc2 when cells are ready to divide.     

Chemotherapy for patients with advanced lung cancer receiving long-term oxygen therapy

Background

Long-term oxygen therapy (LTOT) is sometimes prescribed for patients with advanced lung cancer who are potential candidates for chemotherapy. The aim of this study was to assess the usefulness of chemotherapy for patients with this disease who require LTOT.

Methods

The medical records of 40 patients with advanced lung cancer who received LTOT while undergoing systemic chemotherapy at our institution between January 2009 and December 2014 were retrospectively reviewed. Chemotherapy consisted of cytotoxic or molecular-targeted agents.

Results

Twenty-four patients had adenocarcinoma, 6 had squamous cell carcinoma, and 10 had small cell lung cancer (SCLC). The median survival time from the date of the first chemotherapy cycle performed in conjunction with LTOT was 194 days. In a multivariate analysis, the only factor significantly associated with better prognosis was the line (first or second) of the first chemotherapy with LTOT (hazard ratio =0.42; 95% confidence interval, 0.18 to 0.94). Among the 40 patients, 10 (25%) received chemotherapy during the last 30 days of their lives, 2 of whom died of chemotherapy-related adverse events.

Conclusions

Chemotherapy for patients with advanced lung cancer who receive LTOT may be acceptable if it is the first- or second-line treatment. However, we should be mindful of the potential overuse of chemotherapy and its negative impact on quality of life.     

Neuromedin s is a novel anorexigenic hormone

A novel 36-amino acid neuropeptide, neuromedin S (NMS), has recently been identified in rat brain and has been shown to be an endogenous ligand for two orphan G protein-coupled receptors, FM-3/GPR66 and FM-4/TGR-1. These receptors have been identified as neuromedin U (NMU) receptor type 1 and type 2, respectively. In this study, the physiological role of the novel peptide, NMS, on feeding regulation was investigated. Intracerebroventricular (icv) injection of NMS decreased 12-h food intake during the dark period in rats. This anorexigenic effect was more potent and persistent than that observed with the same dose of NMU. Neuropeptide Y, ghrelin, and agouti-related protein-induced food intake was counteracted by coadministration of NMS. Icv administration of NMS increased proopiomelanocortin mRNA expression in the arcuate nucleus (Arc) and CRH mRNA in the paraventricular nucleus (PVN). Pretreatment with SHU9119 (antagonist for alpha-MSH) and alpha-helical corticotropin-releasing factor-(9-41) (antagonist for CRH) attenuated NMS-induced suppression of 24-h food intake. After icv injection of NMS, Fos-immunoreactive cells were detected in both the PVN and Arc. When neuronal multiple unit activity was recorded in the PVN before and after icv injection of NMS, a significant increase in firing rate was observed 5 min after administration, and this increase continued for 100 min. These results suggest that the novel peptide, NMS, may be a potent anorexigenic hormone in the hypothalamus, and that expression of proopiomelanocortin mRNA in the Arc and CRH mRNA in the PVN may be involved in NMS action on feeding.     

Efficacy of thromboelastography in the management of anticoagulation for veno-venous extracorporeal membrane oxygenation in a coronavirus disease 2019 patient: A case report

Rationale:In coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome refractory to optimal conventional management, we should consider the indication for veno-venous extracorporeal membrane oxygenation (V-V ECMO). Growing evidence indicates that COVID-19 frequently causes coagulopathy, presenting as hypercoagulation and incidental thrombosis. For these reasons, a multifactorial approach with several anticoagulant markers should be considered in the management of anticoagulation using heparin in COVID-19 patients on V-V ECMO.Patient concerns:A 48-year-old man was infected with COVID-19 with a worsening condition manifesting as acute respiratory distress syndrome.Diagnoses:He was refractory to conventional therapy, thus we decided to introduce V-V ECMO. We used heparin as an anticoagulant therapy for V-V ECMO and adjusted the doses of heparin by careful monitoring of the activated clotting time (ACT) and activated partial thromboplastin time (APTT) to avoid both hemorrhagic and thrombotic complications. We controlled the doses of heparin in the therapeutic ranges of ACT and APTT, but clinical hemorrhaging and profound elevation of coagulant marker became apparent.Interventions:Using thromboelastography (TEG; Haemonetics) in addition to ACT and APTT, we were able to clearly detect not only sufficient coagulability of COVID19 on V-V ECMO (citrated rapid thromboelastography-R 0.5 min, angle 75.5°, MA 64.0 mm, citrated functional fibrinogen-MA 20.7 mm) but also an excessive effect of heparin (citrated kaolin -R 42.7 min, citrated kaolin with heparinase 11.7 min).Outcomes:Given the TEG findings indicating an excessive heparin effect, the early withdrawal of ECMO was considered. After an evaluation of the patient''s respiratory capacity, withdrawal from V-V ECMO was achieved and then anticoagulation was stopped. The hemorrhagic complications and elevated thrombotic marker levels dramatically decreased.Lessons:TEG monitoring might be a useful option for managing anticoagulation in COVID-19 patients on V-V ECMO frequently showing a hypercoagulative state and requiring massive doses of heparin, to reduce both hemorrhagic and thrombotic complications.     

Effects of L-carnitine on exercise tolerance in patients with stable angina pectoris

The effects of L-carnitine (900 mg, p.o. daily) on exercise performance were studied in 12 patients with stable effort angina using a multistage treadmill exercise test. Exercise tests were performed at the end of the placebo period and after 4 and 12 weeks of carnitine therapy. While 12 patients experienced angina during treadmill tests in the placebo period, 2 patients were free of angina after treatment with carnitine. The mean exercise time was 11.4 +/- 0.7 min (mean +/- SE) in the placebo period. This increased significantly to 12.2 +/- 0.5 min (p less than 0.05) after 4 weeks and 12.8 +/- 0.5 min (p less than 0.01) after 12 weeks of treatment with carnitine. The time required for 1 mm ST depression to occur was 6.4 +/- 0.9 min in the placebo period. This increased significantly to 7.6 +/- 0.9 min (p less than 0.01) after 4 weeks and 8.8 +/- 1.0 min after 12 weeks of treatment with carnitine. There was significantly less ST segment depression during the same exercise load after 12 weeks of treatment as compared with that in the placebo period (p less than 0.05). The heart rate and the pressure rate product at the same work load showed no significant difference among the 3 testing periods. The results of this study suggest that L-carnitine may improve exercise tolerance in patients with effort angina.     

Replacement of owl monkey centromere satellite by a newly evolved variant was a recent and rapid process

Alpha satellite DNA is a major DNA component of primate centromeres. We previously reported that Azara's owl monkey has two types of alpha satellite DNA, OwlAlp1 and OwlAlp2. OwlAlp2 (344 bp) exhibits a sequence similarity throughout its entire length with alpha satellite DNA of closely related species. OwlAlp1 (185 bp) corresponds to the part of OwlAlp2. Based on the observation that the CENP-A protein binds to OwlAlp1, we proposed that OwlAlp1 is a relatively new repetitive DNA that replaced OwlAlp2 as the centromeric satellite DNA. However, a detailed picture of the evolutionary process of this centromere DNA replacement remains largely unknown. Here, we performed a phylogenetic analysis of OwlAlp1 and OwlAlp2 sequences, and also compared our results to alpha satellite DNA sequences of other primate species. We found that: (i) OwlAlp1 exhibits a higher similarity to OwlAlp2 than to alpha satellite DNA of other species, (ii) OwlAlp1 has a single origin, and (iii) sequence variation is lower in OwlAlp1 than in OwlAlp2. We conclude that OwlAlp1 underwent a recent and rapid expansion in the owl monkey lineage. This centromere DNA replacement could have been facilitated by the heterochromatin reorganization that is associated with the adaptation of owl monkeys to a nocturnal lifestyle.