Effect of Sulfotyrosine and Negatively Charged Amino Acid of Leech-Derived Peptides on Binding and Inhibitory Activity Against Thrombin.

Hirudins, natural sulfo(glyco)proteins, are clinical anticoagulants that directly inhibit thrombin, a key coagulation factor. Their potent thrombin inhibition primarily results from antagonistic interactions with both the catalytic and non-catalytic sites of thrombin. Hirudins often feature sulfate moieties on Tyr residues in their anionic C-terminus region, enabling strong interactions with thrombin exosite-I and effectively blocking its engagement with fibrinogen. Although sulfotyrosines have been identified in various hirudin variants, the precise relationship between sulfotyrosine and the number of negatively charged amino acids within the anionic-rich C-terminus peptide domain for the binding of thrombin has remained elusive. By using Fmoc-SPPS, hirudin dodecapeptides homologous to the C-terminus of hirudin variants from various leech species were successfully synthesized, and the effect of sulfotyrosine and the number of negatively charged amino acids on hirudin-thrombin interactions was investigated. Our findings did not reveal any synergistic effect between an increasing number of sulfotyrosines or negatively charged amino acids and their inhibitory activity on thrombin or fibrinolysis in the assays, despite a higher binding level toward thrombin in the sulfated dodecapeptide Hnip_Hirudin was observed in SPR analysis.

Serological Responses and Predictive Factors of Booster COVID-19 Vaccines in Patients with Hematologic Malignancies.

Patients with hematologic malignancies are reported to have a more severe course of coronavirus disease 2019 (COVID-19) and be less responsive to vaccination. In this prospective study, we aimed to evaluate the serological responses to booster COVID-19 vaccines of Taiwanese patients with hematologic malignancies and identify potential predictive markers for effective neutralizing immunity. This study enrolled 68 patients with hematologic malignancies and 68 age- and gender-matched healthy control subjects who received three doses of vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from 1 January 2022 to 31 October 2022. The SARS-CoV-2 immunoglobulin G (IgG) spike antibody level was measured with the Abbott assay. The effective neutralization capacity was defined as an anti-spike IgG level of ≥4160 AU/mL. Among the 68 patients with hematologic malignancies, 89.7% achieved seroconversion after booster doses. Seven patients with actively treated lymphoma remained seronegative and had the lowest humoral responses among patients with different types of hematologic malignancies. Despite comparable antibody titers between patients and healthy individuals, rates of effective neutralization (66.2% vs. 86.8%, respectively; p = 0.005) were significantly reduced in patients with hematologic malignancies. In a multivariate analysis, the independent predictors for effective neutralization were a lack of B-cell-targeted agents within six months of vaccination (odds ratio, 15.2; 95% confidence interval, 2.7-84.2; p = 0.002) and higher immunoglobulin levels (odds ratio, 4.4; 95% confidence interval, 1.3-14.7; p = 0.017). In conclusion, the majority of patients with hematologic malignancies achieved seroconversion after booster vaccination. Patients with ongoing B-cell depletion and hypogammaglobinemia were identified as having negative predictive markers for effective neutralization.

Subacute two stage metatarsal lengthening with gradual distraction for brachymetatarsia: A consecutive case series and literature review.

BACKGROUND: This study examined the functional and clinical outcomes of subacute two stage metatarsal lengthening with gradual distraction for brachymetatarsia. This technique was developed to overcome the disadvantages of one-stage metatarsal lengthening and gradual distraction. METHODS: Four feet of three patients with congenital brachymetatarsia underwent subacute two stage metatarsal lengthening with gradual distraction. Pain, function, and alignment were assessed preoperatively and at follow-ups using the American Orthopaedic Foot and Ankle Society (AOFAS) lesser metatarsophalangeal-interphalangeal scale, and any complications were recorded. RESULTS: The patients were followed up for a mean of 18.1 ± 6.9 (range, 12.6-28.1) months. The mean metatarsal length gain was 15.2 ± 3.2 (range, 12.1-18.5) mm, and the corresponding percent increase was 32.5 % ± 7.0 % (range, 25.7-41.1 %). The mean AOFAS score (0-100) was 97.5 ± 5.0 at the final follow-up. The external fixator index was 10.2 ± 1.5 (range, 8.1-11.6) days/cm. None of the patients experienced metatarsophalangeal stiffness, subluxation or dislocation of the metatarsophalangeal joint, loss of correction, pin tract infection, delayed union, nonunion, or angular deformities. CONCLUSION: Subacute two stage metatarsal lengthening with gradual distraction is a reliable alternative treatment for brachymetatarsia.

Conditioned Media of Adipose-Derived Stem Cells Suppresses Sidestream Cigarette Smoke Extract Induced Cell Death and Epithelial-Mesenchymal Transition in Lung Epithelial Cells.

The role of the epithelial-mesenchymal transition (EMT) in lung epithelial cells is increasingly being recognized as a key stage in the development of COPD, fibrosis, and lung cancers, which are all highly associated with cigarette smoking and with exposure to second-hand smoke. Using the exposure of human lung cancer epithelial A549 cells and non-cancerous Beas-2B cells to sidestream cigarette smoke extract (CSE) as a model, we studied the protective effects of adipose-derived stem cell-conditioned medium (ADSC-CM) against CSE-induced cell death and EMT. CSE dose-dependently induced cell death, decreased epithelial markers, and increased the expression of mesenchymal markers. Upstream regulator analysis of differentially expressed genes after CSE exposure revealed similar pathways as those observed in typical EMT induced by TGF-ß1. CSE-induced cell death was clearly attenuated by ADSC-CM but not by other control media, such as a pass-through fraction of ADSC-CM or A549-CM. ADSC-CM effectively inhibited CSE-induced EMT and was able to reverse the gradual loss of epithelial marker expression associated with TGF-ß1 treatment. CSE or TGF-ß1 enhanced the speed of A549 migration by 2- to 3-fold, and ADSC-CM was effective in blocking the cell migration induced by either agent. Future work will build on the results of this in vitro study by defining the molecular mechanisms through which ADSC-CM protects lung epithelial cells from EMT induced by toxicants in second-hand smoke.

Artificial peptide-controlled protein release of Zn2+-triggered, self-assembled histidine-tagged protein microparticle.

Protein microparticles have received attention as drug delivery systems because of their high protein stability and prolonged release in vivo. However, most current preparation processes introduce chemical crosslinkers, which often lead to protein inactivation and limit drug efficacy in delivery systems. In this study, we employed the well-known hexahistidine (His)-tag recombinant protein technology and a metal-triggerable collagen-mimetic peptide to enhance the binding strength between the protein and metal ion and fine-tuned the protein drug release. His-tagged proteins self-assembled to form microparticles (∼2 µm) upon zinc ion treatment and sustained protein drug release was achieved in physiological saline. The results also indicated that by adjusting the peptide concentration and N- and C-terminal hexahistidine-tags, protein release could be controlled. Moreover, no protein denaturation was observed. We developed a universal strategy for facile protein microparticle fabrication under mild conditions and we demonstrated its potential as a therapeutics formulation with tunable protein release.

Dongshaea marina gen. nov., sp. nov., a facultatively anaerobic marine bacterium that ferments glucose with gas production.

Two isolates of heterotrophic, facultatively anaerobic, marine bacteria, designated DM1 and DM2T, were recovered from a lagoon sediment sample of Dongsha Island, Taiwan. Cells were Gram-reaction-negative rods. Nearly all of the cells were non-motile and non-flagellated during the late exponential to early stationary phase of growth, while a few of the cells exhibited motility with monotrichous flagellation. The two isolates required NaCl for growth and grew optimally at about 30 °C, 2-3 % NaCl and pH 7-8. They grew aerobically and could achieve anaerobic growth by fermenting d-glucose or other carbohydrates with production of acids and the gases, including CO2 and H2. Ubiquinone Q-8 was the only respiratory quinone. Cellular fatty acids were predominated by C16 : 0, C18 : 1ω7c and C16 : 1ω7c. The major polar lipid was phosphatidylethanolamine. Strains DM1 and DM2T had DNA G+C contents of 52.0 and 51.8 mol%, respectively, as determined by HPLC analysis. Phylogenetic analyses based on 16S rRNA gene sequences clearly indicated that the two isolates formed a distinct genus-level lineage in the family Aeromonadaceae of the class Gammaproteobacteria and was an outgroup with respect to a stable supragenic clade comprising species of the genera Oceanimonas, Oceanisphaera and Zobellella. The phylogenetic data and those from chemotaxonomic, physiological and morphological characterizations support the establishment of a novel species and genus inside the family Aeromonadaceae, for which the name Dongshaea marina gen. nov., sp. nov. is proposed. The type strain is DM2T (=BCRC 81069T=JCM 32096T).

Knockout of ho-1 protects the striatum from ferrous iron-induced injury in a male-specific manner in mice.

Men have worse survival than premenopausal women after intracerebral hemorrhage (ICH). After ICH, overproduction of iron associated with induction of heme oxygenase-1 (HO-1) in brain was observed. Rodent ICH model using ferrous citrate (FC)-infusion into the striatum to simulate iron overload, showed a higher degree of injury severity in males than in females. However, the participation of HO-1 in sex-differences of iron-induced brain injury remains unknown. The present results showed a higher level of HO-1 expression associated with more severe injury in males compared with females after FC-infusion. Estradiol (E2) contributed to lower levels of FC-induced HO-1 expression in females compared with males. Heterozygote ho-1 KO decreased the levels of FC-induced injury severity, histological lesions, behavioral deficits, autophagy and autophagic cell death in the striatum of males but not in females. Moreover, ho-1 deficiency enhanced the neuroprotection by E2 only in males. These results suggested that over induction of HO-1 plays a harmful role in FC-induced brain injury in a male-specific manner. Suppression of HO-1 combined with E2 exhibits a synergistic effect on neuroprotection against FC-induced striatal injury in males. These findings open up the prospect for male-specific neuroprotection targeting HO-1 suppression for patients suffering from striatal iron overload.

Male-Specific Alleviation of Iron-Induced Striatal Injury by Inhibition of Autophagy.

Men exhibit a worse survival rate than premenopausal women after intracerebral hemorrhage (ICH), however, no sex-specific management has been concerned. In a rat model involving infusion of ferrous citrate (FC) that simulates iron accumulation after hemorrhage, a higher degree of autophagy associated with higher injury severity was observed in striatum of males than in females. Since the imbalance between the levels of autophagy and energy demand may lead to cell death, we proposed that FC-induced autophagy is detrimental in a male specific manner and autophagy modulation affects injury severity in a sex-dependent manner. Rapamycin, an autophagy inducer, and conditional knockout gene of autophagy-related protein 7 (Atg7) in dopamine receptor D2 (DRD2) neurons were used to test our hypothesis using a mouse model with striatal FC infusion. The result showed that the levels of autophagic cell death and injury severity were higher in male than in female mice. Pre-treatment of FC-infused females with rapamycin increased the FC-induced behavioral deficit and DRD2 neuron death. However, DRD2 neuron-specific knockout of Atg7 decreased FC-induced injury severity and the number of TUNEL(+) DRD2 neurons in males. These results suggest that autophagy in FC-infusion males is overactive with maladaptive consequences and inhibition of autophagy decreases the severity of FC-induced striatal injury in males. These findings present prospects for male-specific therapeutic strategy that targets autophagy in patients suffering from iron overload.

Inhibition of autophagy as a therapeutic strategy of iron-induced brain injury after hemorrhage.

Premenopausal women have better survival than men after intracerebral hemorrhage, which is associated with iron overproduction and autophagy induction. To examine the participation of neuronal autophagy and estrogen receptor α (ERα) in the E 2-mediated protection, PC12 neurons treated with Atg7 (autophagy-related protein 7) siRNA, rapamycin (an autophagy inducer), or Erα siRNA were applied. To study whether autophagy involves in ß-estradiol 3-benzoate (E 2)-mediated neuroprotection against iron-induced striatal injury, castration and E 2 capsule implantation were performed at 2 weeks and 24 h, respectively, before ferrous citrate (FC) infusion into the caudate nucleus (CN) of Sprague Dawley male and female rats. Furthermore, the role of neuronal autophagy in the sex difference of FC-induced CN injury was confirmed by using conditional knockout Atg7 in dopamine receptor 2 (DRD2)-containing neurons in mice. The results showed that the suppression of FC-induced autophagy by E 2 was abolished by Erα siRNA preincubation. Atg7 silencing simulates and rapamycin diminishes E 2-mediated neuroprotection against FC-induced neurotoxicity. In vivo, FC induced a lower degree of autophagy, autophagic cell death, injury severity, histological lesion and behavioral deficit in female rats than in males. E 2 implantation decreased the levels of both FC-induced autophagy and injury in ovariectomized rats. Moreover, the sex difference of FC-induced CN injury was diminished in Atg7 knockout mice. Thus, suppression of autophagy by E 2 via ERα contributes to less severity of iron-induced brain injury in females than in male. This finding opens up the prospect for a therapeutic strategy targeting autophagic inhibition for patients suffering from intracerebral iron overload.

A Cullin3-KLHL20 Ubiquitin ligase-dependent pathway targets PML to potentiate HIF-1 signaling and prostate cancer progression.

Tumor hypoxia is associated with disease progression and treatment failure, but the hypoxia signaling mechanism is not fully understood. Here, we show that KLHL20, a Cullin3 (Cul3) substrate adaptor induced by HIF-1, coordinates with the actions of CDK1/2 and Pin1 to mediate hypoxia-induced PML proteasomal degradation. Furthermore, this PML destruction pathway participates in a feedback mechanism to maximize HIF-1α induction, thereby potentiating multiple tumor hypoxia responses, including metabolic reprogramming, epithelial-mesenchymal transition, migration, tumor growth, angiogenesis, and chemoresistance. In human prostate cancer, overexpression of HIF-1α, KLHL20, and Pin1 correlates with PML down-regulation, and hyperactivation of the PML destruction pathway is associated with disease progression. Our study indicates that the KLHL20-mediated PML degradation and HIF-1α autoregulation play key roles in tumor progression.

Sex-specific role of thioredoxin in neuroprotection against iron-induced brain injury conferred by estradiol.

BACKGROUND AND PURPOSE: Accumulation of iron after intracerebral hemorrhage causes free radical formation and oxidative damage resulting in liquefaction. The aim of this study was the investigation of molecular mechanisms underlying estrogen-mediated neuroprotective effect against iron-induced brain injury in vivo. METHODS: Age-matched male and female Sprague-Dawley rats were stereotaxically infused with either ferrous citrate (FC) or saline (10 muL) into the right caudate nucleus. Beta-estradiol 3-benzoate (E(2)) capsule was implanted subcutaneously at 24 hours before infusion of FC. The severity of brain injury and neurological deficits were measured by histological quantification and forelimb asymmetry test, respectively. The role of thioredoxin (Trx) in E(2)-mediated neuroprotective effect was examined by intrastriatal administration of a Trx reductase inhibitor, 5,5-dithiobis-(2-nitrobenzoic acid), and small interfering RNA. RESULTS: FC induced greater brain injury in male rats than females. E(2) treatment reduced FC-induced brain injury in both sexes. E(2) significantly increased protein level and activity of Trx in the caudate nucleus of females but not males. Administration of female rats with 5,5-dithiobis-(2-nitrobenzoic acid) or Trx small interfering RNA to the caudate nucleus decreased the protective effect of E(2) against FC-induced injury. The protein and mRNA levels of estrogen receptor alpha, but not estrogen receptor beta, were more abundant in the caudate nucleus of female rats. CONCLUSIONS: Increase of brain Trx activity might play an important role in the E(2)-mediated neuroprotective effect against FC-induced brain injury in female rats. Understanding of the sex differences in the Trx-mediated neuroprotective effect by E(2) might help in improving treatment of brain dysfunction after hemorrhagic stroke and/or head trauma.