Extensively Hydrated but Folded: A Novel State of Globular Proteins Stabilized at High Pressure and Low Temperature

AbstractWe studied conformational fluctuations of the transcription factor c-Myb R2 subdomain (52 residues with three Trp) at high pressure and low temperature (5°C) using two different spectroscopic methods, Trp fluorescence and 1H NMR, on its chemically stable mutant C130I (pseudo-wild-type (WTS)), which has a large internal cavity. As pressure was increased from 3 to 300 MPa, the Trp fluorescence λmax of WTS shifted from 342 to ∼355 nm, clearly showing that the three Trp rings become fully exposed to the polar environment, which usually is taken to indicate that the protein underwent unfolding. In contrast, as pressure was increased from 3 to 300 MPa, the high-field-shifted 1H NMR signals characteristic of the folded state showed a still higher-field shift, but no significant changes in their intensity. The last result unequivocally shows that the protein remains largely folded at 300 MPa. The apparent discrepancy between the two predictions would only be solved if one were to postulate the existence of an extensively hydrated but folded state in WTS. Intriguingly, such a state was not found in a cavity-filling mutant of WTS, C130I/V103L, suggesting that this state is mediated by cavity hydration. The generality and significance of this state in proteins are discussed

Expert consensus on hospitalization for assessment: a survey in Japan for a new forensic mental health system

<p>Abstract</p> <p>Background</p> <p>In Japan, hospitalization for the assessment of mentally disordered offenders under the Act on Medical Care and Treatment for the Persons Who Had Caused Serious Cases under the Condition of Insanity (the Medical Treatment and Supervision Act, or the MTS Act) has yet to be standardized.</p> <p>Methods</p> <p>We conducted a written survey that included a questionnaire regarding hospitalization for assessment; the questionnaire consisted of 335 options with 9 grades of validity for 60 clinical situations. The survey was mailed to 50 Japanese forensic mental health experts, and 42 responses were received.</p> <p>Results</p> <p>An expert consensus was established for 299 of the options. Regarding subjects requiring hospitalization for assessment, no consensus was reached on the indications for electroconvulsive therapy (ECT) or for confronting the offenders regarding their offensive behaviors.</p> <p>Conclusions</p> <p>The consensus regarding hospitalization for assessment and its associated problems were clarified. The consensus should be widely publicized among practitioners to ensure better management during the hospitalization of mentally disordered offenders for assessment.</p

Optimal liver drainage rate for survival in patients with unresectable malignant hilar biliary obstruction using 3D-image volume analyzer

Background: Drainage exceeding 50% of total liver volume is a beneficial prognostic factor in patients with unresectable malignant hilar biliary obstruction (UMHBO). However, it is unclear what threshold percentage of total liver volume drained ('liver drainage rate') significantly improves survival in patients with UMHBO who received systemic chemotherapy. Objectives: We aimed to assess the optimal liver drainage rate that improves survival in patients with UMHBO receiving chemotherapy using a three-dimensional (3D)-image volume analyzer. Design: This study was a single-center retrospective cohort study. Methods: Data from 90 patients with UMHBO who received chemotherapy after endoscopic biliary drainage using metal stents at Okayama University Hospital from January 2003 to December 2020 were reviewed. The liver drainage rate was calculated by dividing the drained liver volume by the total liver volume using a 3D-image volume analyzer. The primary endpoint was overall survival by liver drainage rate. The secondary endpoints were time to recurrent biliary obstruction (TRBO) and prognostic factors. Results: The median total liver volume was 1172 (range: 673-2032) mL, and the median liver drainage rate was 83% (range: 50-100). Overall survival was 376 (95% CI: 271-450) days, and patients with >80% drainage (n = 67) had significantly longer survival than those with 80% liver drainage [hazard ratio (HR): 0.35, 95% CI: 0.20-0.62, p = 0.0003] and hilar cholangiocarcinoma (HR: 0.30, 95% CI: 0.17-0.50, p Conclusion: In patients with UMHBO scheduled for chemotherapy, >80% drainage is associated with improved survival. Further prospective multicenter studies are needed to verify the results of this study

Structures and mechanisms of actin ATP hydrolysis

The major cytoskeleton protein actin undergoes cyclic transitions between the monomeric G-form and the filamentous F-form, which drive organelle transport and cell motility. This mechanical work is driven by the ATPase activity at the catalytic site in the F-form. For deeper understanding of the actin cellular functions, the reaction mechanism must be elucidated. Here, we show that a single actin molecule is trapped in the F-form by fragmin domain-1 binding and present their crystal structures in the ATP analog-, ADP-Pi-, and ADP-bound forms, at 1.15-Å resolutions. The G-to-F conformational transition shifts the side chains of Gln137 and His161, which relocate four water molecules including W1 (attacking water) and W2 (helping water) to facilitate the hydrolysis. By applying quantum mechanics/molecular mechanics calculations to the structures, we have revealed a consistent and comprehensive reaction path of ATP hydrolysis by the F-form actin. The reaction path consists of four steps: 1) W1 and W2 rotations; 2) PG–O3B bond cleavage; 3) four concomitant events: W1–PO3− formation, OH− and proton cleavage, nucleophilic attack by the OH− against PG, and the abstracted proton transfer; and 4) proton relocation that stabilizes the ADP-Pi–bound F-form actin. The mechanism explains the slow rate of ATP hydrolysis by actin and the irreversibility of the hydrolysis reaction. While the catalytic strategy of actin ATP hydrolysis is essentially the same as those of motor proteins like myosin, the process after the hydrolysis is distinct and discussed in terms of Pi release, F-form destabilization, and global conformational changes

Molecular Subtypes of Breast Cancers from Myanmar Women: A Study of 91 Cases at Two Pathology Centers

BACKGROUND: Breast cancer is the most common cancer in Myanmar women. Revealing the hormonal receptor status, human epidermal growth factor receptor 2 (HER2) and Ki-67 expression is useful for estimating patient prognosis as well as determination of treatment strategy. However, immunohistochemical features and classification of molecular subtypes in breast cancers from Myanmar remain unknown. METHODS: The clinicopathological features of 91 breast cancers from Myanmar women were examined. Immunohistochemistry was performed on tissue specimens with antibodies to estrogen receptor (ER), progesterone receptor (PgR), HER2, Ki-67, cytokeratin (CK)5/6 and CK14. Immunohistochemistry-based molecular subtyping was conducted. RESULTS: Breast cancers in Myanmar women were relatively large, high grade with frequent metastatic lymph nodes. Of the 91 patients, tumors with ER positive, PgR positive, and HER2 positive were 57.1%, 37.4%, and 28.6%, respectively. The most prevalent subtype was luminal B (HER2-) (39.6%), followed by HER2 (22.0%), triple negative (TN)-basal-like (12.1%), luminal A (11.0%), TN-null (8.8%) and luminal B (HER2+) (6.6%). The mean Ki-67 expression of 91 cases was 33.9% (33.9% ± 19.2%) and the median was 28% (range; 4%-90%). The mean Ki-67 expression of luminal A, luminal B, HER2 and TN-basal-like/ null was 7%, 30%, 40%, and 57%/43%, respectively. A higher Ki-67 expression significantly correlated with a higher grade, larger size and higher stage of malignancy. CONCLUSIONS: We, for the first time, investigated the histopathological features of breast cancers from Myanmar women. Myanmar breast cancers appeared to be aggressive in nature, as evidenced by high frequency of poor-prognosis subtypes with high level of Ki-67 expression

Risk-adjusted therapy for pediatric non-T cell ALL improves outcomes for standard risk patients: results of JACLS ALL-02

This study was a second multicenter trial on childhood ALL by the Japan Childhood Leukemia Study Group (JACLS) to improve outcomes in non-T ALL. Between April 2002 and March 2008, 1138 children with non-T ALL were enrolled in the JACLS ALL-02 trial. Patients were stratified into three groups using age, white blood cell count, unfavorable genetic abnormalities, and treatment response: standard risk (SR), high risk (HR), and extremely high risk (ER). Prophylactic cranial radiation therapy (PCRT) was abolished except for CNS leukemia. Four-year event-free survival (4yr-EFS) and 4-year overall survival (4yr-OS) rates for all patients were 85.4% ± 1.1% and 91.2% ± 0.9%, respectively. Risk-adjusted therapy resulted in 4yr-EFS rates of 90.4% ± 1.4% for SR, 84.9% ± 1.6% for HR, and 66.5% ± 4.0% for ER. Based on NCI risk classification, 4yr-EFS rates were 88.2% in NCI-SR and 76.4% in NCI-HR patients, respectively. Compared to previous trial ALL-97, 4yr-EFS of NCI-SR patients was significantly improved (88.2% vs 81.2%, log rank p = 0.0004). The 4-year cumulative incidence of isolated (0.9%) and total (1.5%) CNS relapse were significantly lower than those reported previously. In conclusion, improved EFS in NCI-SR patients and abolish of PCRT was achieved in ALL-02