Inactive Form Research Articles

Teprotumumab for the Treatment of Thyroid Eye Disease: Why Should We Keep Our Eyes "Wide Open"?-A Clinical and Pharmacovigilance Point of View.

Objectives: Thyroid eye disease (TED) treatment has been recently revolutionized with the approval of teprotumumab, a targeted insulin growth factor 1 receptor (IGF1R) inhibitor. To date, teprotumumab is the only FDA-approved drug for treating TED. In this article, we would like to temper the current enthusiasm around IGF1R inhibitors. Methods: critical review of the literature by independent academic practitioners. Results: several questions should be raised. First, "how an orphan drug has become a blockbuster with annual sales exceeding $1 billion?" Teprotumumab infusions are expensive, costing about USD 45,000 for one infusion and USD 360,000 for eight infusions in a 75 kg patient. Teprotumumab approval was based on two randomized clinical trials investigating active (clinical activity score ≥ 4) TED patients. Despite this, teprotumumab was approved by the FDA for "the treatment of TED" without distinguishing between active and inactive forms. The second question is as follows: "how can a new drug, compared only to a placebo, become the new standard without being compared to historically established gold standard medical or surgical treatments?" Teprotumumab has never been compared to other medical treatments in active TED nor to surgery in chronic TED. Up to 75% of patients may experience proptosis regression after treatment discontinuation. Finally, ototoxicity has emerged as a potentially devastating side effect requiring frequent monitoring. Investigation into the long-term side effects, especially in women of childbearing age, is also warranted. Conclusions: Teprotumumab is undoubtedly a major treatment option in TED. However, before prescribing a drug, practitioners should assess its benefit/risk ratio based on the following: (i) evidence-based medicine; (ii) their empirical experience; (iii) the cost/benefit analysis; (iv) the long-term outcomes and safety profile.

Study on Ce-MOF-derived oxides as morphology-tunable catalyst supports for dry reforming of methane

Dry reforming of methane (DRM) using CH4 and CO2 as feedstocks to catalytically produce high-value synthesis gas products has great application prospects. However, as a high-temperature heterogeneous catalytic reaction, the challenge lies in preparing efficient and stable catalysts for long-term operation. To enhance the catalytic performance by optimizing support, this study proposed regulating the catalyst structure and properties using Ce-based metal-organic framework (MOF) derivatives. Compared with the conventional Ni/CeO2, Ni/CeO2-MOF catalysts performed better in DRM. Especially, Ni/CeO2-UiO-66 demonstrated significant improvement in both catalytic activity and stability. It was also noticed that the Ni/CeO2-MOF catalysts had a potential benefit in limiting the conversion of carbon species to inactive forms given the relatively lower carbon gasification temperatures at their surfaces. The advantage of Ni/CeO2-MOF catalysts was attributed to their better void structure and reduction characteristics, as well as higher oxygen vacancy concentration and improved CO2 adsorption activation capability after pre-activation. This study revealed that MOF-derived supports had distinctive structural characteristics, which were manifested as an important component in high-temperature catalyst systems.

Insights from Structure-Based Simulations into the Persulfidation of Uridine Diphosphate-Glycosyltransferase71c5 Facilitating the Reversible Inactivation of Abscisic Acid.

The action of abscisic acid (ABA) is closely related to its level in plant tissues. Uridine diphosphate-glycosyltransferase71c5 (UGT71C5) was characterized as a major UGT enzyme to catalyze the formation of the ABA-glucose ester (ABA-GE), a reversible inactive form of free ABA in Arabidopsis thaliana (thale cress). UGTs function in a mode where the catalytic base deprotonates an acceptor to allow a nucleophilic attack at the anomeric center of the donor, achieving the transfer of a glucose moiety. The proteomic data revealed that UGT71C5 can be persulfidated. Herein, an experimental method was employed to detect the persulfidation site of UGT71C5, and the computational methods were further used to identify the yet unknown molecular basis of ABA glycosylation as well as the regulatory role of persulfidation in this process. Our results suggest that the linker and the U-shaped loop are regulatory structural elements: the linker is associated with the binding of uridine diphosphate glucose (UPG) and the U-shaped loop is involved in binding both UPG and ABA.It was also found that it is through tuning the dynamics of the U-shaped loop that is accompanied by the movement of tyrosine (Y388) that the persulfidation of cysteine (C311) leads to the catalytic residue histidine (H16) being in place, preparing for the deprotonation of ABA, and then reorientates UPG and deprotonated ABA closer to the 'Michaelis' complex, facilitating the transfer of a glucose moiety. Ultimately, the persulfidation of UGT71C5 is in favor of ABA glycosylation. Our results provide insights into the molecular details of UGT71C5 recognizing substrates and insights concerning persulfidation as a possible mechanism for hydrogen sulfide (H2S) to modulate the content of ABA, which helps us understand how modulating ABA level strengthens plant tolerance.

ZmGDIα-hel counters the RBSDV-induced reduction of active gibberellins to alleviate maize rough dwarf virus disease

Maize rough dwarf disease (MRDD) threatens maize production globally. The P7-1 effector of the rice black-streaked dwarf virus (RBSDV) targets maize Rab GDP dissociation inhibitor alpha (ZmGDIα) to cause MRDD. However, P7-1 has difficulty recruiting a ZmGDIα variant with an alternative helitron-derived exon 10 (ZmGDIα-hel), resulting in recessive resistance. Here, we demonstrate that P7-1 can recruit another maize protein, gibberellin 2-oxidase 13 (ZmGA2ox7.3), which also exhibits tighter binding affinity for ZmGDIα than ZmGDIα-hel. The oligomerization of ZmGA2ox7.3 is vital for its function in converting bioactive gibberellins into inactive forms. Moreover, the enzymatic activity of ZmGA2ox7.3 oligomers increases when forming hetero-oligomers with P7-1/ZmGDIα, but decreases when ZmGDIα-hel replaces ZmGDIα. Viral infection significantly promotes ZmGA2ox7.3 expression and oligomerization in ZmGDIα-containing susceptible maize, resulting in reduced bioactive GA1/GA4 levels. This causes an auxin/cytokinin imbalance and ultimately manifests as MRDD syndrome. Conversely, in resistant maize, ZmGDIα-hel counters these virus-induced changes, thereby mitigating MRDD severity.

Anchorene, a carotenoid-derived growth regulator, modulates auxin homeostasis by suppressing GH3-mediated auxin conjugation.

Anchorene, identified as an endogenous bioactive carotenoid-derived dialdehyde and diapocarotenoid, affects root development by modulating auxin homeostasis. However, the precise interaction between anchorene and auxin, as well as the mechanisms by which anchorene modulates auxin levels, remain largely elusive. In this study, we conducted a comparative analysis of anchorene's bioactivities alongside auxin and observed that anchorene induces multifaceted auxin-like effects. Through genetic and pharmacological examinations, we revealed that anchorene's auxin-like activities depend on the indole-3-pyruvate-dependent auxin biosynthesis pathway, as well as the auxin inactivation pathway mediated by Group II Gretchen Hagen 3 (GH3) proteins that mainly facilitate the conjugation of indole-3-acetic acid (IAA) to amino acids, leading to the formation of inactivated storage forms. Our measurements indicated that anchorene treatment elevates IAA levels while reducing the quantities of inactivated IAA-amino acid conjugates and oxIAA. RNA sequencing further revealed that anchorene triggers the expression of numerous auxin-responsive genes in a manner reliant on Group II GH3s. Additionally, our in vitro enzymatic assays and biolayer interferometry (BLI) assay demonstrated anchorene's robust suppression of GH3.17-mediated IAA conjugation with glutamate. Collectively, our findings highlight the significant role of carotenoid-derived metabolite anchorene in modulating auxin homeostasis, primarily through the repression of GH3-mediated IAA conjugation and inactivation pathways, offering novel insights into the regulatory mechanisms of plant bioactive apocarotenoids.

SymRK regulates G-protein signaling during nodulation in soybean (Glycine max) by modifying RGS phosphorylation and activity.

Molecular inter-species dialogue between leguminous plants and nitrogen-fixing rhizobia results in the development of symbiotic root nodules. This is initiated by several nodulation-related receptors present on the surface of root hair epidermal cells. We have shown previously that specific subunits of heterotrimeric G proteins and their regulatory RGS (regulator of G-protein signaling) proteins act as molecular links between the receptors and downstream components during nodule formation in soybeans. Nod factor receptor 1 (NFR1) interacts with and phosphorylates RGS proteins to regulate the G-protein cycle. Symbiosis receptor-like kinases (SymRK) phosphorylate Gα to make it inactive and unavailable for Gβγ. We now show that like NFR1, SymRK also interacts with the RGS proteins to phosphorylate them. Phosphorylated RGS has higher GTP accelerating activity, which favors conversion of active Gα to its inactive form. Phosphorylation of RGS proteins is physiologically relevant, as overexpression of a phospho-mimic version of RGS protein enhances nodule formation in soybean. These results reveal an intricate fine-tuning of the G-protein signaling during nodulation, where a negative regulator (Gα) is effectively deactivated by RGS due to the concerted efforts of several receptor proteins to ensure adequate nodulation.

NLRP3 Negative Regulation Mechanisms in the Resting State and Its Implications for Therapeutic Development.

The NACHT-, leucine-rich-repeat-, and pyrin domain-containing protein 3 (NLRP3) is a critical intracellular sensor of the innate immune system that detects various pathogen- and danger-associated molecular patterns, leading to the assembly of the NLRP3 inflammasome and release of interleukin (IL) 1β and IL-18. However, the abnormal activation of the NLRP3 inflammasome has been implicated in the pathogenesis of autoinflammatory diseases such as cryopyrin-associated autoinflammatory syndromes (CAPS) and common diseases such as Alzheimer's disease and asthma. Recent studies have revealed that pyrin functions as an indirect sensor, similar to the plant guard system, and is regulated by binding to inhibitory 14-3-3 proteins. Upon activation, pyrin transitions to its active form. NLRP3 is predicted to follow a similar regulatory mechanism and maintain its inactive form in the cage model, as it also acts as an indirect sensor. Additionally, newly developed NLRP3 inhibitors have been found to inhibit NLRP3 activity by stabilizing its inactive form. Most studies and reviews on NLRP3 have focused on the activation of the NLRP3 inflammasome. This review highlights the molecular mechanisms that regulate NLRP3 in its resting state, and discusses how targeting this inhibitory mechanism can lead to novel therapeutic strategies for NLRP3-related diseases.

Identification and comparison of intestinal microbial diversity in patients at different stages of hepatic cystic echinococcosis

There is a significant focus on the role of the host microbiome in different outcomes of human parasitic diseases, including cystic echinococcosis (CE). This study was conducted to identify the intestinal microbiome of patients with CE at different stages of hydatid cyst compared to healthy individuals. Stool samples from CE patients as well as healthy individuals were collected. The samples were divided into three groups representing various stages of hepatic hydatid cyst: active (CE1 and CE2), transitional (CE3), and inactive (CE4 and CE5). One family member from each group was selected to serve as a control. The gut microbiome of patients with different stages of hydatid cysts was investigated using metagenomic next-generation amplicon sequencing of the V3–V4 region of the 16S rRNA gene. In this study, we identified 4862 Operational Taxonomic Units from three stages of hydatid cysts in CE patients and healthy individuals with a combined frequency of 2,955,291. The most abundant genera observed in all the subjects were Blautia, Agathobacter, Faecalibacterium, Bacteroides, Bifidobacterium, and Prevotella. The highest microbial frequency was related to inactive forms of CE, and the lowest frequency was observed in the group with active forms. However, the lowest OTU diversity was found in patients with inactive cysts compared with those with active and transitional cyst stages. The genus Agatobacter had the highest OTU frequency. Pseudomonas, Gemella, and Ligilactobacillus showed significant differences among the patients with different stages of hydatid cysts. Additionally, Anaerostipes and Candidatus showed significantly different reads in CE patients compared to healthy individuals. Our findings indicate that several bacterial genera can play a role in the fate of hydatid cysts in patients at different stages of the disease.

Assessing the Efficacy of Protease Inactivation for the Preservation of Bioactive Amphibian Skin Peptides.

The skin of amphibians is a rich source of peptides with a wide range of biological activities. They are stored in secretory granules in an inactive form. Upon stimulation, they are secreted together with proteases into the skin. Once activated, they rapidly exert their biological effects, including fighting microorganisms and predators, while their excess is immediately destroyed by the released proteases. To keep bioactive peptides in their initial form, it is necessary to inhibit these enzymes. Several inhibitors for this purpose have previously been mentioned; however, there has not been any reliable comparison of their efficiency so far. Here, we studied the efficiency of methanol and hydrochloric and formic acids, as well as phenylmethylsulfonyl fluoride, in the inhibition of nine frog peptides with the known sequence, belonging to five families in the secretion of Pelophylax esculentus. The results demonstrated that methanol had the highest inhibitory efficiency, while phenylmethylsulfonyl fluoride was the least efficient, probably due to its instability in aqueous media. Possible cleavages between certain amino acid residues in the sequence were established for each of the inhibitors. These results may be helpful for future studies on the nature of proteases and on prediction of the possible cleavage sites in novel peptides.

The potential role of CAR-T in Multiple Myeloma Treatment. A review

Background: Multiple myeloma (MM) is a hematologic malignancy, which causes accumulation of plasma cells in the bone marrow. The symptoms of MM are associated with organ dysfunction and include hypercalcemia, renal failure, anaemia and bone destruction. A relatively new and promising therapeutic option for MM is CAR-T therapy. Aim of the study: The study aimed to outline the role of CAR-T therapy in MM treatment.Material and methods: We conducted a literature review containing 24 articles. We described the role of CAR-T in MM therapy, its therapeutic points, the effectiveness of therapy, and its side effects.Results: CAR-T cells transduced with CAR can recognize specific antigens and kill the cancer cells. For MM these specific antigens are integrin β7, SLAMF7, CD138, BCMA, GPRC5D and FCRL5. Integrin β7 in its active form, can be found in MM cells, whereas in other blood cells, integrin β7 is in the inactive form. The expression of SLAMF7 on MM cells is high and uniform, but its function is not clear: expression of SLAMF7 in MM is suspected to increase the survival and adhesion of MM cells to bone marrow stromal cells. CD138's strong expression on MM cells is contributing to their development and proliferation. BCMA expression was not detected in other human tissues, only in MM cells. GPRC5D is highly expressed in bone marrow samples from MM patients, and minimally expressed in other hematologic malignancies. FCRL5 is a protein marker found specifically on plasma cells in MM, its increased expression promotes B cell proliferation. The AlloCAR-T therapy also seems to be an effective method.CAR-T therapy has also adverse effects including cytokine release syndrome, neurological toxicity, haematological disorders and infusion fever. Conclusions: The effects of CAR-T therapy in MM are really promising and give real benefits to patients. For this reason, it should be further developed and subjected to further research.

Glycyrrhizin intake higher than the current international guidelines has no detectable hypermineralocorticoid-like effect in dogs.

Glycyrrhizin-enriched extracts from licorice root are associated with numerous health benefits and are widely used in phytotherapy. There is evidence that ingesting glycyrrhizin beyond threshold concentrations can impact the metabolism of cortisol, inhibiting its conversion to an inactive form, cortisone, via 11-hydroxysteroid dehydrogenase. A consequence can be a form of hypermineralocorticoidism, with elevated potassium excretion and associated hypertension, as demonstrated in rats and humans. Here, 3 orally dosed concentrations of glycyrrhizin (0.2, 0.4 and 0.6 mg/kg bodyweight/day) were assessed over 28 days in dogs. As the current guidelines reflect a lack of reliable data in this species, our aim was to provide relevant information for doses above the current guidelines. The specific purpose of this study was to demonstrate that an intake of licorice with a known therapeutic benefit to dogs does not cause hypermineralocorticoidism in this species. No changes in blood pressure, nor electrolyte excretion were observed in the dogs given these three glycyrrhizin concentrations.

Design of gelatin cryogel scaffolds with the ability to release simvastatin for potential bone tissue engineering applications

Tissue engineering aims to improve or restore damaged tissues by using scaffolds, cells and bioactive agents. In tissue engineering, one of the most important concepts is the scaffold because it has a key role in keeping up and promoting the growth of the cells. It is also desirable to be able to load these scaffolds with drugs that induce tissue regeneration/formation. Based on this, in our study, gelatin cryogel scaffolds were developed for potential bone tissue engineering applications and simvastatin loading and release studies were performed. Simvastatin is lipoliphic in nature and this form is called inactive simvastatin (SV). It is modified to be in hydrophilic form and converted to the active form (SVA). For our study's drug loading and release process, simvastatin was used in both inactive and active forms. The blank cryogels and drug-loaded cryogels were prepared at different glutaraldehyde concentrations (1, 2, and 3%). The effect of the crosslinking agent and the amount of drug loaded were discussed with morphological and physicochemical analysis. As the glutaraldehyde concentration increased gradually, the pores size of the cryogels decreased and the swelling ratio decreased. For the release profile of simvastatin in both forms, we can say that it depended on the form (lipophilic and hydrophilic) of the loaded simvastatin.

Exercise training-driven exosomal miRNA-323–5p activity suppresses adipogenic conversion of 3T3-L1 cells via the DUSP3/ERK pathway

Adipose-derived stem cell (ASC)-released exosomes (ASCexos) have multiple biological activities. We examined the effect of ASCexos derived from the inguinal adipose tissue of exercise-trained rats (EX-ASCexos) on adipogenic conversion of 3T3-L1 cells and analyzed their microRNA (miRNA) expression profiles. Differentiation of 3T3-L1 cells into adipocytes was performed for 9 d with EX-ASCexos or ASCexos from sedentary control rats (SED-ASCexos), and the expression of proteins and miRNA involved in adipogenic differentiation were determined. EX-ASCexos but not SED-ASCexos attenuated 3T3-L1 adipocyte differentiation with increased phosph-Ser112PPARγ expression, the inactive form of PPARγ. These differentiated adipocytes were also accompanied by increased phosph-Thr202/Tyr204ERK and decreased dual-specificity phosphatase 3 (DUSP3) levels. The exosomal miRNAs miR-323–5p, miR-433–3p, and miR-874–3p were identified specifically in EX-ASCexos. Of these, miR-323–5p mimic replicated the EX-ASCexo-induced suppression of 3T3-L1 adipocyte differentiation and altered adipogenesis-related factor expression. In conclusion, exercise training-driven exosomal miR-323–5p suppressed 3T3-L1 adipogenesis by increasing phosph-Ser112PPARγ expression, while phosph-Thr202/Tyr204ERK accumulation inhibited DUSP3 expression.

Thermal Inactivation, Denaturation and Aggregation Processes of Papain-Like Proteases.

The investigation into the behavior of ficin, bromelain, papain under thermal conditions holds both theoretical and practical significance. The production processes of medicines and cosmetics often involve exposure to high temperatures, particularly during the final product sterilization phase. Hence, it's crucial to identify the "critical" temperatures for each component within the mixture for effective technological regulation. In light of this, the objective of this study was to examine the thermal inactivation, aggregation, and denaturation processes of three papain-like proteases: ficin, bromelain, papain. To achieve this goal, the following experiments were conducted: (1) determination of the quantity of inactivated proteases using enzyme kinetics with BAPNA as a substrate; (2) differential scanning calorimetry (DSC); (3) assessment of protein aggregation using dynamic light scattering (DLS) and spectrophotometric analysis at 280 nm. Our findings suggest that the inactivation of ficin and papain exhibits single decay step which characterized by a rapid decline, then preservation of the same residual activity by enzyme stabilization. Only bromelain shows two steps with different kinetics. The molecular sizes of the active and inactive forms are similar across ficin, bromelain, and papain. Furthermore, the denaturation of these forms occurs at approximately the same rate and is accompanied by protein aggregation.

Hydroxychloroquine attenuates double-stranded RNA-stimulated hyper-phosphorylation of tristetraprolin/ZFP36 and AU-rich mRNA stabilization.

The human innate immune system recognizes dsRNA as a pathogen-associated molecular pattern that induces a potent inflammatory response. The primary source of pathogenic dsRNA is cells infected with replicating viruses, but can also be released from uninfected necrotic cells. Here, we show that the dsRNA poly(I:C) challenge in human macrophages activates the p38 MAPK-MK2 signalling pathway and subsequently the phosphorylation of tristetraprolin (TTP/ZFP36). The latter is an mRNA decay-promoting protein that controls the stability of AU-rich mRNAs (AREs) that code for many inflammatory mediators. Hydroxychloroquine (HCQ), a common anti-malaria drug, is used to treat inflammatory and autoimmune disorders and, controversially, during acute COVID-19 disease. We found that HCQ reduced the dsRNA-dependent phosphorylation of p38 MAPK and its downstream kinase MK2. Subsequently, HCQ reduced the abundance and protein stability of the inactive (phosphorylated) form of TTP. HCQ reduced the levels and the mRNA stability of poly (I:C)-induced cytokines and inflammatory mRNAs like TNF, IL-6, COX-2, and IL-8 in THP-1 and primary blood monocytes. Our results demonstrate a new mechanism of the anti-inflammatory role of HCQ at post-transcriptional level (TTP phosphorylation) in a model of dsRNA activation, which usually occurs in viral infections or RNA release from necrotic tissue.

A viral effector blocks the turnover of a plant NLR receptor to trigger a robust immune response

Plant intracellular nucleotide-binding and leucine-rich repeat immune receptors (NLRs) play a key role in activating a strong pathogen defense response. Plant NLR proteins are tightly regulated and accumulate at very low levels in the absence of pathogen effectors. However, little is known about how this low level of NLR proteins is able to induce robust immune responses upon recognition of pathogen effectors. Here, we report that, in the absence of effector, the inactive form of the tomato NLR Sw-5b is targeted for ubiquitination by the E3 ligase SBP1. Interaction of SBP1 with Sw-5b via only its N-terminal domain leads to slow turnover. In contrast, in its auto-active state, Sw-5b is rapidly turned over as SBP1 is upregulated and interacts with both its N-terminal and NB-LRR domains. During infection with the tomato spotted wilt virus, the viral effector NSm interacts with Sw-5b and disrupts the interaction of Sw-5b with SBP1, thereby stabilizing the active Sw-5b and allowing it to induce a robust immune response.

Volumetric differences in the temporomandibular joint in patients with condylar hyperplasia in active and passive state, SPECT/CT study.

Condylar hyperplasia (CH) is a progressive and deforming disease that modifies anatomy of the temporomandibular joint (TMJ) structures. This study aims to correlate the metabolic bone activity of the condyle measured by SPECT with the volumetry anatomic information from the condyle, fossa and joint space provided by CT images, in patients with CH in active and inactive forms. A cross-sectional comparative study was performed with a set of 116 images from healthy and diagnosed CH patients to compare volumetric measures of the TMJ. Images were acquired through a bone tissue mask using a three-dimensional DICOM reconstruction for SPECT/CT and CBCT images and the Threshold option for segmentation with standardized values for each tissue on the HU scale. there are differences (p<0.01), with greater condylar volume on the affected side in patients with active CH compared to passive CH. The volume of the glenoid cavity shows no differences in either form of CH (p>0.05), however, there were differences for the volume of the joint space on the affected right side of hemimandibular elongation (HE) in the active form. The volume of the mandibular condyle on the affected side in CH cases were larger in HE cases in active and inactive form (p<0.01) compared to healthy patients. Similar results were presented for the glenoid cavity and joint space. Volumetric anatomical evaluation of TMJ structures, as well as information on condylar metabolic activity, can be obtained from SPECT/CT. The study shows a greater condylar volume on the affected side of the CH compared to the contralateral side, but there are more significant differences in the active than in the inactive form.

Goal-Directed Use of Prothrombin Complex Concentrates in Liver Transplantation: Is a Plasma-Free Procedure Feasible?

Background: Fresh frozen plasma (FFP) transfusions have been the mainstay of hemostatic intervention for the treatment of bleeding and coagulation abnormalities arising during liver transplantation (LT) for decades. However, numerous clinical studies showed that FFP has many side effects, including the risk of pathogen transmission, transfusion-associated circulatory overload (TACO), transfusion-related immunomodulation (TRIM), and transfusion-related acute lung injury (TRALI). These adverse events are particularly challenging in patients undergoing LT, who often suffer from severe portal hypertension, poor renal function and coexisting cardiac disease.The aims of this review are to summarize the pharmacological properties of currently available PCCs, to represent the theoretical benefits and the possible risks related to the use of these drugs in patients undergoing LT, and, finally, to review the current literature on the topic in order to highlight the evidence that currently supports PCC use in LT patients. Methods: The current literature on the topic was reviewed in order to highlight the evidence that currently supports PCC use in LT patients. Results: Prothrombin complex concentrates (PCCs) may offer several advantages when compared to FFP. Indeed, PCCs have been shown to reduce the risk of TACO, which during liver transplantation may deteriorate portal hypertension, increase intraoperative bleeding, and possibly reduce survival rates. One of the major concerns for PCC use is thrombogenicity. However, currently available PCCs are much safer as they contain inactivated forms of the vitamin K-dependent coagulation factors and protein C, protein S, antithrombin and/or heparin. Nowadays, the use of PCCs to correct coagulation abnormalities that occur during LT is an increasingly widespread practice. However, it is not yet clear what level of evidence supports this practice, and what the risks associated with it are. Conclusions: Administration of PCC in LT patients to correct haemostatic abnormalities seems to be well-tolerated, but the relationship between PCC use and thromboembolic events in the postoperative period remains unclear. Adequately powered, methodologically sound trials are urgently required for more definitive conclusions about the efficacy and safety of PCCs in a broad phenotype of LT recipients.

Steroid sulfatase in mouse liver and testis: Characterization, ontogeny and localization

Steroid hormones often circulate in the plasma as inactive sulfated forms, such as estrone sulfate and dehydroepiandrosterone sulfate. The enzyme steroid sulfatase (STS) converts these steroids into active forms, mainly estrogens, in peripheral tissues. STS is present in most tissues, but it occurs at higher levels in certain organs, notably liver and placenta. In this study, we examined the tissue distribution of STS in a prominent laboratory model, the house mouse (Mus musculus). Tissues included were heart, liver, small intestine, skeletal muscle, and gonads of both sexes. An 3H-estrone-sulfate conversion assay was used to measure STS activity in tissue homogenates and extracts. STS activities were high for hepatic tissue homogenates of both genders. Testicular STS levels were similar to those of liver, while STS activities of ovary, small intestine, heart, and muscle were considerably lower. The specific STS inhibitors, EMATE and STX-64 virtually eliminated STS activity in hepatic microsomes and cytosols, verifying that the observed enzyme activity was due to STS. Enzyme kinetic assays showed Km values of 8.6 µM for liver and 9.1 µM for testis, using E1S as substrate. Hepatic and testicular STS activities, measured in CHAPS-extracted microsome, were low up to 5 weeks of age and were higher through 56 weeks. Western blotting, with a specific STS antibody, confirmed the presence of STS protein (65 Da) in both liver and testis. Immunofluorescence of tissue sections detected the presence of STS protein in hepatocytes, in testicular Leydig cells and in seminiferous tubules (Leydig cells and developing germ cells). These results suggest that STS may have a significant role in testicular function.

Gene networks governing the response of a calcareous sponge to future ocean conditions reveal lineage-specific XBP1 regulation of the unfolded protein response.

Marine sponges are predicted to be winners in the future ocean due to their exemplary adaptive capacity. However, while many sponge groups exhibit tolerance to a wide range of environmental insults, calcifying sponges may be more susceptible to thermo-acidic stress. To describe the gene regulatory networks that govern the stress response of the calcareous sponge, Leucetta chagosensis (class Calcarea, order Clathrinida), individuals were subjected to warming and acidification conditions based on the climate models for 2100. Transcriptome analysis and gene co-expression network reconstruction revealed that the unfolded protein response (UPR) was activated under thermo-acidic stress. Among the upregulated genes were two lineage-specific homologs of X-box binding protein 1 (XBP1), a transcription factor that activates the UPR. Alternative dimerization between these XBP1 gene products suggests a clathrinid-specific mechanism to reversibly sequester the transcription factor into an inactive form, enabling the rapid regulation of pathways linked to the UPR in clathrinid calcareous sponges. Our findings support the idea that transcription factor duplication events may refine evolutionarily conserved molecular pathways and contribute to ecological success.