Subsequent menstrual disorder after spontaneous menarche in Turner syndrome

OBJECTIVE

Turner syndrome (TS) is a congenital disease characterized by delayed puberty, ovarian dysgenesis and short stature. Although most patients are diagnosed with primary amenorrhea, approximately 15-20% of patients with TS are reported to have spontaneous menarche. However, little is known about their menstruation status after spontaneous menarche. In the current study, we investigated the menstrual abnormalities after spontaneous menarche in TS patients.

DESIGN

Retrospective study.

PATIENTS

This study included TS patients with spontaneous menarche at Osaka Police Hospital or Komura Women's Clinic between April 2015 and December 2019.

MEASUREMENTS

Data regarding the age of menarche, menstruation status and chromosomal karyotype were collected and retrospectively analyzed.

RESULTS

Of 172 TS patients, 32 with spontaneous menarche were identified. The median age of menarche was 12 years old. Premature ovarian insufficiency (POI) after menarche was observed in 12 patients (37.5%) and the median age at menopause was 20 years old. The average period from spontaneous menarche to menopause in these patients was 5.1 years. Five patients (15.6%) had irregular menstruation and 15 (46.9%) had regular menstruation. When examined according to the structural abnormality of the X chromosome, all patients with structural abnormality of the X chromosome were diagnosed with POI after spontaneous menarche, and none with mosaic without structural abnormality were diagnosed with POI.

CONCLUSION

Approximately one-third of TS patients with spontaneous menarche were diagnosed with POI after menarche for an average of 5.1 years. Counseling is required for TS patients and their parents, including information about menstrual abnormalities or fertility preservation.

Advanced Chemical Methods for Stereoselective Sialylation and Their Applications in Sialoglycan Syntheses

Sialic acid is an important component of cell surface glycans, which are responsible for many vital body functions and should therefore be thoroughly studied to understand their biological roles and association with disorders. The difficulty of isolating large quantities of homogenous-state sialoglycans from natural sources has inspired the development of the corresponding chemical synthesis methods affording acceptable purities, yields, and amounts. However, the related syntheses are challenging because of the difficulties in α-glycosylation of sialic acid, which arises from its certain structural features such as the absence of a stereodirecting group at the C3 position and presence of carboxyl group at the anomeric position. Moreover, the structural complexities of sialoglycans with diverse numbers and locations of sialic acid on the glycan chains pose additional barriers. Thus, efficient α-stereoselective routes to sialosides remain highly sought after, although various types of sialyl donors/acceptors have been developed for the straightforward synthesis of α-sialosides. Herein, we review the latest progress in the α-stereoselective synthesis of sialosides and their applications in the preparation of gangliosides and other sialoglycans.

Impact of grip strength and balance function on the exercise capacity in pulmonary hypertension

Funding Acknowledgements

Type of funding sources: None.

【Background】

Patients with pulmonary hypertension (PH) suffer from poor exercise capacity due to impaired oxygenation or reduced cardiac output. However, the relationship between exercise capacity and physical functions remains unclear.

【Purpose】

The purpose of this study is to investigate the relationship between exercise capacity and physical functions in pulmonary hypertension.

【Methods】

From February 2018 to June 2020, 94 patients (61.3 ± 14.7 years old, 69.1% females) with group 1/3/4/5 PH underwent cardiac catheterization, 6-minute walking distance (6MWD), and physical function measurements simultaneously. The physical functions was measured using muscle strength (grip strength, knee extension muscle strength), balance function (one leg standing time), and short physical performance battery (SPPB). Exercise capacity was measured by 6MWD. 

【Results】

The study cohort consists of 22/8/60/4 (23.4%/8.5%/63.8%/4.3%) patients with group 1/3/4/5 PH, respectively. The average age of each group was 50.7/64.7/63.1/66.0 years old, respectively. A total of 194 measurements of physical functions were evaluated from 94 patients and employed in multivariate logistic regression analysis using adaptive-LASSO methods with the 6MWD (476.2 ± 107.5m) as a dependent variable. WHO functional class (class II: standardized β=-0.35, 95% confidence interval (CI) [-0.54 - -0.16], p < 0.001), class III: β=-0.60, 95%CI [-0.90 - -0.30], p < 0.001), mixed venous oxygen saturation (SvO2: β=0.11, 95%CI [0.03 - 0.19], p = 0.008), pulmonary vascular resistance (PVR: β=-0.16, 95%CI [-0.25 - -0.07], p < 0.001), grip strength (β=0.20, 95%CI [0.09 - 0.31], p < 0.001), one leg standing time (β=0.10, 95%CI [0.00 - 0.20], p = 0.049) , and 4m gait speed test (β=-0.28, 95%CI [-0.36 - -0.19], p < 0.001) were associated with 6MWD.

【Conclusions】

Grip strength and balance function, as well as SvO2 and PVR, were associated with the exercise capacity in pulmonary hypertension.

FRET detects lateral interaction between transmembrane domain of EGF receptor and ganglioside GM3 in lipid bilayers

Ganglioside GM3 in the plasma membranes suppresses cell growth by preventing the autophosphorylation of the epidermal growth factor receptor (EGFR). Biological studies have suggested that GM3 interacts with the transmembrane segment of EGFR. Further biophysical experiments are particularly important for quantitative evaluation of the peptide-glycolipid interplay in bilayer membranes using a simple reconstituted system. To examine these interactions in this way, we synthesized the transmembrane segment of EGFR bearing a nitrobenzoxadiazole fluorophore (NBD-TM) at the N-terminus. The affinity between EGFR and GM3 was evaluated based on Förster resonance energy transfer (FRET) between NBD-TM and ATTO594-labeled GM3 in bilayers where their non-specific interaction due to lateral proximity was subtracted by using NBD-labeled phospholipid. This method for selectively detecting the specific lipid-peptide interactions in model lipid bilayers disclosed that the lateral interaction between GM3 and the transmembrane segment of EGFR plays a certain role in disturbing the formation of active EGFR dimers.

Defining raft domains in the plasma membrane

Many plasma membrane (PM) functions depend on the cholesterol concentration in the PM in strikingly nonlinear, cooperative ways: fully functional in the presence of physiological cholesterol levels (35~45 mol%), and nonfunctional below 25 mol% cholesterol; namely, still in the presence of high concentrations of cholesterol. This suggests the involvement of cholesterol-based complexes/domains formed cooperatively. In this review, by examining the results obtained by using fluorescent lipid analogs and avoiding the trap of circular logic, often found in the raft literature, we point out the fundamental similarities of liquid-ordered (Lo)-phase domains in giant unilamellar vesicles, Lo-phase-like domains formed at lower temperatures in giant PM vesicles, and detergent-resistant membranes: these domains are formed by cooperative interactions of cholesterol, saturated acyl chains, and unsaturated acyl chains, in the presence of >25 mol% cholesterol. The literature contains evidence, indicating that the domains formed by the same basic cooperative molecular interactions exist and play essential roles in signal transduction in the PM. Therefore, as a working definition, we propose that raft domains in the PM are liquid-like molecular complexes/domains formed by cooperative interactions of cholesterol with saturated acyl chains as well as unsaturated acyl chains, due to saturated acyl chains' weak multiple accommodating interactions with cholesterol and cholesterol's low miscibility with unsaturated acyl chains and TM proteins. Molecules move within raft domains and exchange with those in the bulk PM. We provide a logically established collection of fluorescent lipid probes that preferentially partition into raft and non-raft domains, as defined here, in the PM.

Prognostic significance of bone marrow FDG uptake in patients with gynecological cancer

We investigated the prognostic significance and the underlying mechanism of increased bone marrow (BM) 2-(18F) fluoro-2-deoxy-D-glucose as a tracer (FDG)-uptake in patients with gynecological cancer. A list of patients diagnosed with cervical, endometrial, and ovarian cancer from January 2008 to December 2014 were identified. Then, through chart reviews, 559 patients who underwent staging by FDG-positron emission tomography (PET)/computed tomography (CT) and subsequent surgical resection were identified, and their clinical data were reviewed retrospectively. BM FDG-uptake was evaluated using maximum standardized uptake value (SUVmax) and BM-to-aorta uptake ratio (BAR). As a result, we have found that increased BAR was observed in 20 (8.7%), 21 (13.0%), 21 (12.6%) of cervical, endometrial, and ovarian cancer, respectively, and was associated with significantly shorter survival. Increased BAR was also closely associated with increased granulopoiesis. In vitro and in vivo experiments revealed that tumor-derived granulocyte colony-stimulating factor (G-CSF) was involved in the underlying causative mechanism of increased BM FDG-uptake, and that immune suppression mediated by G-CSF-induced myeloid-derived suppressor cells (MDSCs) is responsible for the poor prognosis of this type of cancer. In conclusion, increased BM FDG-uptake, as represented by increased BAR, is an indicator of poor prognosis in patients with gynecological cancer.

ABCA13 dysfunction associated with psychiatric disorders causes impaired cholesterol trafficking

ATP-binding cassette subfamily A member 13 (ABCA13) is predicted to be the largest ABC protein, consisting of 5058 amino acids and a long N-terminal region. Mutations in the ABCA13 gene were reported to increase the susceptibility to schizophrenia, bipolar disorder, and major depression. However, little is known about the molecular functions of ABCA13 or how they associate with psychiatric disorders. Here, we examined the biochemical activity of ABCA13 using HEK293 cells transfected with mouse ABCA13. The expression of ABCA13 induced the internalization of cholesterol and gangliosides from the plasma membrane to intracellular vesicles. Cholesterol internalization by ABCA13 required the long N-terminal region and ATP hydrolysis. To examine the physiological roles of ABCA13, we generated Abca13 KO mice using CRISPR/Cas and found that these mice exhibited deficits of prepulse inhibition. Vesicular cholesterol accumulation and synaptic vesicle endocytosis were impaired in primary cultures of Abca13 KO cortical neurons. Furthermore, mutations in ABCA13 gene associated with psychiatric disorders disrupted the protein's subcellular localization and impaired cholesterol trafficking. These findings suggest that ABCA13 accelerates cholesterol internalization by endocytic retrograde transport in neurons and that loss of this function is associated with the pathophysiology of psychiatric disorders.

Stereoselective Synthesis of Diglycosyl Diacylglycerols with Glycosyl Donors Bearing a β-Stereodirecting 2,3-Naphthalenedimethyl Protecting Group

Diglycosyl diacylglycerols (DGDGs) are major components of Gram-positive bacterial plasma membranes and are involved in the immune response systems. The chemical synthesis of DGDGs has been highly demanded, as it will allow the elucidation of their biological functions at the molecular level. In this study, we have developed a novel β-stereodirecting 2,3-naphthalenedimethyl (NapDM) protecting group that is orthogonal to protecting groups commonly used in oligosaccharide synthesis. The NapDM group can be easily cleaved under TFA-mediated acidic conditions. Futhermore, we demonstrated the application of this protecting group to an acyl protecting-group-free strategy by utilizing the NapDM group for the synthesis of DGDGs. This strategy features the use of the β-stereodirecting NapDM group as an acid-cleavable permanent protecting group and late-stage glycosylation of monoglycosyl diacylglycerol acceptors, enabling the stereoselective synthesis of three different bacterial DGDGs with unsaturated fatty acid chain(s).

Two cases of giant peritoneal inclusion cysts requiring treatment after total laparoscopic hysterectomy

Peritoneal inclusion cysts (PICs) often develop in post-operative patients. Since the incidence of adhesions is lower with laparoscopic surgery than with open surgery, PICs are less likely to occur in the former. Although post-operative adhesions or PICs rarely develop after laparoscopic surgery (such as total laparoscopic hysterectomy: TLH), we encountered two cases of giant PICs with abdominal pain after TLH. In Case 1, strong adhesion was already present when TLH was performed. Therefore, this case may have been predisposed to the development of adhesions in the abdominal cavity. However, no adhesions were observed during TLH in case 2, and there were no risk factors, such as pre-operative adhesions and endometriosis. Therefore, adhesions and PICs may develop even after TLH, and approaches need to be considered for their prevention.

Incorporation of pretreatment leukocytosis and thrombocytosis into the FIGO staging system for prognosis in surgically treated endometrial cancer

OBJECTIVE

To investigate the impact of incorporating pretreatment leukocytosis and/or thrombocytosis in the FIGO staging system on prognostic prediction among women with surgically treated endometrial cancer.

METHODS

Retrospective review of clinical data from 900 women with endometrial cancer treated at Osaka University Hospital, Japan, between 2000 and 2016. The effect of concurrent leukocytosis and thrombocytosis on the prediction of recurrence and survival outcomes was evaluated via receiver operating characteristic (ROC) curve analysis and the Kaplan-Meier method.

RESULTS

Among 678 women with Stage I-III disease, pretreatment leukocytosis or thrombocytosis alone were not prognostic indicators, but concurrent pretreatment leukocytosis and thrombocytosis was associated with significantly shorter survival (PFS, P<0.001; OS, P=0.004). In contrast, pretreatment leukocytosis, pretreatment thrombocytosis, and concurrent pretreatment leukocytosis and thrombocytosis did not provide any prognostic information for women with Stage IV disease. In ROC curve analysis, incorporation of concurrent pretreatment leukocytosis and thrombocytosis into the FIGO staging system resulted in a higher area under the curve for predicting recurrence for women with Stages I-III disease (0.770 vs 0.755; P=0.045).

CONCLUSION

Incorporating concurrent pretreatment leukocytosis and thrombocytosis into the FIGO staging system might improve predictive performance and allow additional risk stratification for women with Stage I-III endometrial cancer.

Significance of Pretreatment C-Reactive Protein, Albumin, and C-Reactive Protein to Albumin Ratio in Predicting Poor Prognosis in Epithelial Ovarian Cancer Patients

To investigate the prognostic significance of pretreatment C-reactive protein (CRP), albumin, and the CRP to albumin ratio (CRP/Alb) in epithelial ovarian cancer (EOC) patients. Clinical data from 308 EOC patients between April 2007 and March 2016 were collected and retrospectively reviewed. The cutoff values for CRP, albumin, and CRP/Alb were defined by receiver operating characteristics (ROC) analyses. Univariate or multivariate analysis was conducted to evaluate the prognostic significance of these factors for disease-specific survival. The cutoff values for CRP, albumin, and CRP/Alb were 0.76, 3.8, and 0.048 by ROC analysis, respectively. Cox regression analyses demonstrated that an elevated CRP/Alb is an independent predictor of short disease-specific survival irrespective of clinical stage or optimal surgery rate. When examined according to clinical stage, elevated CRP/Alb was associated with short disease-specific survival in both early-stage and advanced-stage patients. Cox regression analyses demonstrated that an elevated CRP, but not lower albumin, is also an independent predictor of short disease-specific survival. When two prognosticators were compared, CRP/Alb was found to be superior to CRP for predicting disease-specific survival in EOC patients. Pretreatment elevated CRP/Alb is a predictor of shorter survival in EOC patients regardless of clinical stage.

Indirect synthetic route to α-l-fucosides via highly stereoselective construction of α-l-galactosides followed by C6-deoxygenation

We developed an indirect synthetic method for α-l-fucosides. Based on the fact that l-fucose is 6-deoxy-l-galactose, our strategy consists of the stereoselective construction of α-l-galactoside and its conversion to α-l-fucoside via C6-deoxygenation. The formation of α-l-galactoside is strongly directed using 4,6-O-di-tert-butylsilylene(DTBS)-protected l-galactosyl donors. The DTBS-directed α-l-galactosylation showed broad substrate applicability along with excellent coupling yield and α-selectivity. In the C6-deoxygenation of α-l-galactosides, the Barton-McCombie reaction facilitated the conversion to l-fucosides with good yield. To demonstrate the applicability of our method, we synthesized naturally occurring α-l-fucosides.

Control of Lipid Bilayer Phases of Cell-Sized Liposomes by Surface-Engineered Plasmonic Nanoparticles

Liquid-ordered (Lo)-phase domains, a cholesterol-rich area on lipid bilayers, have attracted significant attention recently because of their relevance to lipid rafts, the formation/collapse of which is associated with various kinds of information exchange through the plasma membrane. Here, we demonstrate that the formation/collapse of Lo-phase domains in cell-sized liposomes, that is, giant unilamellar vesicles (GUVs), can be controlled with bioactive plasmonic nanoparticles and light. The nanoparticles were prepared by surface modification of gold nanorods (AuNRs) using a cationized mutant of high-density lipoprotein (HDL), which is a natural cholesterol transporter. Upon the addition of surface-engineered AuNRs to GUVs with the mixed domains of Lo and liquid-disorder (Ld) phases, the Lo domains collapsed and solid-ordered (So)-phase domains were formed. The reverse phase transition was achieved photothermally, with the AuNRs loaded with cholesterol. During these transitions, the AuNRs appeared to be selectively localized on the less fluidic domain (Lo or So) in the phase-mixed GUVs. These results indicate that the phase transitions occur through the membrane binding of the AuNRs followed by spontaneous/photothermal transfer of cholesterol between the AuNRs and GUVs. Our strategy to develop bioactive AuNRs potentially enables spatiotemporal control of the formation/collapse of lipid rafts in living cells.

The role of myeloid-derived suppressor cells in increasing cancer stem-like cells and promoting PD-L1 expression in epithelial ovarian cancer

The aim of this study was to investigate the role of myeloid-derived suppressor cells (MDSC) in the induction of cancer stem-like cells (CSC) and programmed death ligand 1 (PD-L1) expression in ovarian cancer. CSC were defined as tumor cells expressing high levels of aldehyde dehydrogenase 1 (ALDH 1). We inoculated G-CSF-expressing or Mock-expressing ovarian cancer cells into mice, and the frequencies of MDSC and CSC in tumors of these models were compared by flow cytometry. To directly demonstrate the role of MDSC in the induction of CSC and the increase in PD-L1 expression, we performed in vitro co-culture. MDSC and CSC (ALDH-high cells) were more frequently observed in G-CSF-expressing cell-derived tumors than in Mock-expressing cell-derived tumors. Co-culture experiments revealed that MDSC increased the number of CSC via the production of PGE2. Moreover, PGE2 produced by MDSC increased tumor PD-L1 expression via the mammalian target of rapamycin (mTOR) pathway in ovarian cancer cells. In an in vitro experiment in which ovarian cancer cells were co-cultured with MDSC, higher expression of PD-L1 was observed in CSC than in non-CSC (ALDH-low cells). Furthermore, by immunofluorescence staining, we found that PD-L1 was co-expressed with ALDH1 in in vivo mouse models. In conclusion, PGE2 produced by MDSC increases the stem cell-like properties and tumor PD-L1 expression in epithelial ovarian cancer. Depleting MDSC may be therapeutically effective against ovarian cancer by reducing the number of CSC and tumor PD-L1 expression.

Homeostatic and pathogenic roles of GM3 ganglioside molecular species in TLR4 signaling in obesity

Innate immune signaling via TLR4 plays critical roles in pathogenesis of metabolic disorders, but the contribution of different lipid species to metabolic disorders and inflammatory diseases is less clear. GM3 ganglioside in human serum is composed of a variety of fatty acids, including long‐chain (LCFA) and very‐long‐chain (VLCFA). Analysis of circulating levels of human serum GM3 species from patients at different stages of insulin resistance and chronic inflammation reveals that levels of VLCFA‐GM3 increase significantly in metabolic disorders, while LCFA‐GM3 serum levels decrease. Specific GM3 species also correlates with disease symptoms. VLCFA‐GM3 levels increase in the adipose tissue of obese mice, and this is blocked in TLR4‐mutant mice. In cultured monocytes, GM3 by itself has no effect on TLR4 activation; however, VLCFA‐GM3 synergistically and selectively enhances TLR4 activation by LPS/HMGB1, while LCFA‐GM3 and unsaturated VLCFA‐GM3 suppresses TLR4 activation. GM3 interacts with the extracellular region of TLR4/MD2 complex to modulate dimerization/oligomerization. Ligand‐molecular docking analysis supports that VLCFA‐GM3 and LCFA‐GM3 act as agonist and antagonist of TLR4 activity, respectively, by differentially binding to the hydrophobic pocket of MD2. Our findings suggest that VLCFA‐GM3 is a risk factor for TLR4‐mediated disease progression.

Pretreatment tumor-related leukocytosis misleads positron emission tomography-computed tomography during lymph node staging in gynecological malignancies

The accuracy of fluorine-18-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG-PET/CT) can be influenced by the increased glycolytic activity of inflammatory lesions. Here, using clinical data obtained from gynecological cancer patients, tumor samples and animal models, we investigate the impact of pretreatment tumor-related leukocytosis (TRL) on the diagnostic performance of 18F-FDG-PET/CT in detecting pelvic and paraaortic lymph node metastasis. We demonstrate that pretreatment TRL misleads 18F-FDG-PET/CT during lymph node staging in gynecological malignancies. In the mechanistic investigations, we show that the false-positive 18F-FDG-PET/CT result for detecting nodal metastasis can be reproduced in animal models of TRL-positive cancer bearing G-CSF expressing cervical cancer cells. We also show that increased 18F-FDG uptake in non-metastatic nodes can be explained by the MDSC-mediated premetastatic niche formation in which proinflammatory factors, such as S100A8 or S100A9, are abundantly expressed. Together, our results suggest that the MDSC-mediated premetastatic niche created in the lymph node of TRL-positive patients misleads 18F-FDG-PET/CT for detecting nodal metastasis.

Clinical effects of switching from minodronate to denosumab treatment in patients with postmenopausal osteoporosis: a retrospective study

Background

Denosumab is a major treatment option for patients with postmenopausal osteoporosis; however, the evidence for its use is lacking. Therefore, in this 24-month retrospective study, we aimed to evaluate the effects of switching from minodronate (MIN) to denosumab in these patients.

Methods

Patients with postmenopausal osteoporosis either switched from MIN to denosumab (Group 1; n = 32) or continued MIN treatment (Group 2; n = 24). Bone mineral density (BMD) of the lumbar spine (L2–L4) and femoral neck was assessed at baseline and every 6 months for 24 months. Serum bone-specific alkaline phosphatase (BAP) and N-terminal telopeptide were measured at baseline, 12 months, and 24 months.

Results

Twenty-nine of the 32 patients (90.6%) in group 1 and all patients (24/24) in group 2 completed the 24-month follow-up. Switching from MIN to denosumab (Group 1) significantly increased lumbar BMD at 12, 18, and 24 months (6.1, 7.4, and 9.6%, respectively) and femoral neck BMD at 12, 18, and 24 months (2.8, 3.2, and 3.4%, respectively), whereas MIN continuous treatment (Group 2) showed no significant difference from baseline. Switching therapy also showed a significant decrease in serum BAP from baseline to 12 and 24 months (− 19.3 and − 26.5%, respectively) and serum NTX from baseline to 12 months (− 13.1%), whereas continuous MIN treatment failed to show any significant differences from baseline.

Conclusion

Switching from MIN to denosumab in patients with postmenopausal osteoporosis showed clinical benefits with regard to BMD and bone turnover markers in comparison with continuous MIN treatment. It may therefore be a valid treatment option in the clinical setting.

Efficient diversification of GM3 gangliosides via late-stage sialylation and dynamic glycan structural studies with 19F solid-state NMR

GM3 gangliosides have been synthesized via late-stage α-sialylation using a macro-bicyclic sialyl donor. ¹⁹F solid-state NMR analysis of the C5-NHTFAc GM3 analog on a model membrane revealed the influence of cholesterol on glycan dynamics.

On-Membrane Dynamic Interplay between Anti-GM1 IgG Antibodies and Complement Component C1q

Guillain-Barré syndrome, an autoimmune neuropathy characterized by acute limb weakness, is often preceded by Campylobacter jejuni infection. Molecular mimicry exists between the bacterial lipo-oligosaccharide and human ganglioside. Such C. jejuni infection induces production of immunoglobulin G1 (IgG1) autoantibodies against GM1 and causes complement-mediated motor nerve injury. For elucidating the molecular mechanisms linking autoantigen recognition and complement activation, we characterized the dynamic interactions of anti-GM1 IgG autoantibodies on ganglioside-incorporated membranes. Using high-speed atomic force microscopy, we found that the IgG molecules assemble into a hexameric ring structure on the membranes depending on their specific interactions with GM1. Complement component C1q was specifically recruited onto these IgG rings. The ring formation was inhibited by an IgG-binding domain of staphylococcal protein A bound at the cleft between the CH2 and CH3 domains. These data indicate that the IgG assembly is mediated through Fc-Fc interactions, which are promoted under on-membrane conditions due to restricted translational diffusion of IgG molecules. Reduction and alkylation of the hinge disulfide impaired IgG ring formation, presumably because of an increase in conformational entropic penalty. Our findings provide mechanistic insights into the molecular processes involved in Guillain-Barré syndrome and, more generally, into antigen-dependent interplay between antibodies and complement components on membranes.