[Endometriosis and microbiom]

Az endometriosis multifaktoriális betegség, melynek szűrése és kezelése komoly kihívások elé állítja a nőgyógyászokat. Jelenleg a hormonális kezelés – például GnRH-agonista injekciók, gesztagénimplantátumok – és az érintett szövet műtéti eltávolítása, illetve méretének csökkentése az endometriosis leggyakoribb kezelési módszerei. Jelenleg megbízható noninvazív módszerek hiányában az endometriosis igazolásának legbiztosabb módszere a műtéti feltárás. Kutatócsoportunk – részben saját eredményekre támaszkodva, részben széles körű irodalmi adatok alapján – arra a következtetésre jutott, hogy az alsó, illetve felső női genitalis traktus és a bél mikrobiomja kiemelkedő szerepet játszik az endometriosis kialakulásában. Az említett területek baktériumközösségének jelenleginél részletesebb feltérképezése fontos lépés lehet az endometriosis patomechanizmusának megértésében, és új diagnosztikai módszereket is biztosíthat a klinikum számára. A mikrobiom-vizsgálatok összehasonlíthatósága azonban megköveteli, hogy a jövőbeli, prospektív vizsgálatok során szigorú és standardizált módszertant alkalmazzanak annak érdekében, hogy tisztázni lehessen a mikrobiom pontos szerepét a betegség patogenezisében, a klinikai kép formálásában és a terápia monitorozásában. Orv Hetil. 2024; 165(1): 3–13.

[Immune cell functionality during pregnancy]

A magzat immunológiai felismerése a sikeres terhesség feltétele. Ennek alapját a decidualizáció teremti meg, melynek révén létrejön az embrió befogadására alkalmas szöveti környezet. A decidualizáció során kialakuló speciális szövet endokrin és immunológiai feladatokat ellátó önálló szerv, amely szigorúan szabályozott kapcsolatot tart fenn az embrióval, vagyis az embrió maga is aktív résztvevője a megtermékenyülésnek. A terhesség immunológiájának megértése szempontjából rendkívül fontos, hogy a magzat és az anya immunrendszere közötti kölcsönhatás dinamikusan változik, vagyis a terhesség immunológiai stádiumokkal jellemezhető. Napjainkban a terhesség kronológiáját az immunológiai órával reprezentálják („immune clock”): e szerint az implantáció feltétele a korábban elképzelhetetlennek tartott gyulladásos miliő, amelyet a magzati növekedéshez szükséges antiinflammatorikus környezet vált fel, és amelyet a szülés megindulásához nélkülözhetetlen, újfent gyulladásos immunválasz kialakulása követ. A terhességhez történő alkalmazkodás nagy rugalmasságot igényel az anyai immunrendszer részéről annak érdekében, hogy egyidejűleg valósuljon meg az apai alloantigénekkel szembeni tolerancia, a placenta és a magzat optimális fejlődése és a fertőzések/xenobiotikumok elleni védelem. Mindez csak speciális és szorosan együttműködő immunmiliő kialakításával érhető el az anyai–magzati felszínen, ahol a természetes és az adaptív immunrendszer sejtes és szolúbilis összetevői ráhangolódnak a hormonális miliőre, együttműködnek a mikrobiommal, és megfelelő választ adnak a trophoblastok immunmoduláló hatásaira. A természetes és az adaptív folyamatok összehangoltságának megváltozása infertilitáshoz, a beágyazódás zavaraihoz és terhességi szövődményekhez vezethet, ezért megismerésének diagnosztikus és terápiás következményei vannak. Orv Hetil. 2023; 164(51): 2006–2015.

EMACO for treatment of gestational trophoblastic neoplasia: A multinational multicenter study

OBJECTIVE

To investigate the efficacy and toxicity of etoposide, methotrexate, actinomycin D alternating with cyclophosphamide, and vincristine (EMACO) for treatment of gestational trophoblastic neoplasia, and for factors independently associated with EMACO resistance and disease-specific death in an international cohort.

METHODS

Medical records of GTN patients who received EMACO during 1986-2019 from gestational trophoblastic disease centers from four countries including the USA, Thailand, Hungary, and Brazil, were retrospectively reviewed. Among 335 GTN patients, 266 patients who received EMACO as primary chemotherapy were included in the primary treatment group, and 69 patients who received EMACO after relapse/resistance to single-agent chemotherapy were included in the prior treatment group.

RESULTS

Three-quarters (76.1%) of all patients achieved remission, and the survival rate was 89%. The prior treatment group had better outcomes than the primary treatment group relative to remission rate (87.0% vs. 73.3%, p = 0.014) and number of EMACO cycles to achieve remission (3 vs. 6 cycles, p < 0.001). Sustained remission increased to 87.2% in EMACO-resistant patients treated with later-line chemotherapy. Number of metastatic organs ≥2 (adjusted odds ratio [aOR]: 2.33, p = 0.049) was the only independent predictor of EMACO resistance among overall patients. Interval from index pregnancy ≥7 months (aOR: 4.34, p = 0.001), and pretreatment hCG >100,000 IU/L (aOR: 2.85, p = 0.028) were independent predictors of EMACO resistance in the high-risk subgroup. The only factor independently associated with disease-specific death was EMACO resistance (aOR: 176.04, p < 0.001).

CONCLUSIONS

EMACO is an effective treatment for GTN. Number of metastatic organs and EMACO resistance were the independent predictors of EMACO resistance and disease-specific death, respectively.

A decidualizáció klinikai vonatkozásai

A sikeres fogantatás és terhesség elengedhetetlen összetevője a decidualizáció, amely az endometrium szerkezeti és funkcionális átalakulását jelenti. A folyamat magában foglalja a méhnyálkahártya szerkezeti változásait, a spirális arteriolák átalakulását, az endometriumban fellelhető, illetve később oda vándorló leukocyták számbeli és funkcionális adaptációját és a decidualis stromasejtek funkcionális és morfológiai változásait. A decidualizáció részeként az embrionális eredetű trophoblastsejtek szabályozott inváziót hajtanak végre az anyai eredetű szövetben, létrehozva a méhlepényt. A folyamat sikeréhez hozzájárul a trophoblastsejtek különleges antigenitása, illetve az immunológiai értelemben vett graft (magzat) és host (anya) között hormonok, citokinek és több receptor-ligand kapcsolat révén létrejövő kommunikáció. E folyamatok zavarai több, a fogamzást, beágyazódást és sikeres terhességet fenyegető kórkép alapját képezik, úgymint ismétlődő vetélés, praeeclampsia, méhen belüli sorvadás vagy koraszülés. Ebben a dolgozatunkban áttekintjük az élettani decidualizáció anatómiai, immunológiai és molekuláris alapjait, hogy aztán kitérjünk a szülészeti klinikumban előforduló gyakori kórképekre, melyek hátterében részben vagy egészen a decidualizáció valamely zavara állhat. Orv Hetil. 2022; 163(46): 1823–1833.

A single sensor controls large variations in zinc quotas in a marine cyanobacterium

Marine cyanobacteria are critical players in global nutrient cycles that crucially depend on trace metals in metalloenzymes, including zinc for CO₂ fixation and phosphorus acquisition. How strains proliferating in the vast oligotrophic ocean gyres thrive at ultra-low zinc concentrations is currently unknown. Using Synechococcus sp. WH8102 as a model we show that its zinc-sensor protein Zur differs from all other known bacterial Zur proteins in overall structure and the location of its sensory zinc site. Uniquely, Synechococcus Zur activates metallothionein gene expression, which supports cellular zinc quotas spanning two orders of magnitude. Thus, a single zinc sensor facilitates growth across pico- to micromolar zinc concentrations with the bonus of banking this precious resource. The resultant ability to grow well at both ultra-low and excess zinc, together with overall lower zinc requirements, likely contribute to the broad ecological distribution of Synechococcus across the global oceans.

The zinc-sensor protein Zur in a marine cyanobacterium is distinct from those in other bacteria in structure and location of its sensory zinc site, and facilitates growth across a range of zinc concentrations via activation of a metallothionein gene.

A természetes ölősejtek szerepe az anyai-magzati immunhomeostasis fenntartásában

Összefoglaló. A sikeres fogantatás, beágyazódás és terhesség komplex és szervezett kommunikációt igényel az embrió (allograft) és az anya (gazda) immunrendszere között. A különböző leukocyta-alcsoportok fontos szerepet játszanak az immunválasz szervezésében a magzati–anyai határfelületen. Vannak bizonyos hasonlóságok a tumorsejteknek az immunrendszert kijátszó kóros és az embrionális eredetű trophoblastsejteknek az anyai deciduába irányuló fiziológiás inváziója között. A decidualis vagy uterinalis természetes ölősejtek a természetes ölősejtek speciális részhalmaza, és a macrophagokkal és a dendritikus sejtekkel együtt a veleszületett immunrendszer részét képezik, ezért ők az első immunsejtek, amelyek kapcsolatba lépnek bármely behatolóval, legyen az daganat vagy embrionális szövet. Érdekes módon a decidualis természetes ölősejtek nemcsak nem támadják meg az invazív trophoblastsejteket, hanem kifejezetten elősegítik azok progresszióját. Angiogenikus aktivitásuk megkönnyíti és koordinálja a kialakuló méhlepény helyi vascularis átalakulását. Dolgozatunkban áttekintjük a trophoblastsejtek és a decidualis természetes ölősejtek kölcsönhatásait, a decidualis természetes ölősejtek szerepét a decidua vascularisatiójában és immunháztartásában. Orv Hetil. 2022; 163(19): 734–742.

Summary. Successful conception, implantation and pregnancy require a complex and organized communication between the embryonal (allograft) and the maternal (host) immune system. Different leukocyte subsets have an important role in orchestrating the immune response at the fetal-maternal interface. There are certain similarities between the immune invasion of tumor cells and the physiological invasion of the trophoblastic cells of embryonic origin into the maternal decidua. The decidual natural killer cells are a special subset of natural killer cells and alongside with macrophages and dendritic cells, they are part of the innate immune system therefore they are the first immune cells contacting any intruder whether it is a tumor or embryonic tissue. Interestingly decidual natural killer cells not only do not eliminate invasive trophoblastic cells, but specifically promote their progression. Their angiogenic activity facilitates and coordinates local vascular remodeling of the forming placenta. In this article we review the different nature of trophoblastic cell and decidual natural killer cell interaction, the role of decidual natural killer cells in the vascularization and immune homeostasis of the decidua. Orv Hetil. 2022; 163(19): 734–742.

Application of a novel microscopic technique for quantifying CA125 binding to circulating mononuclear cells in longitudinal specimens during treatment for ovarian cancer

Background

Measurement of serum CA125, an antigenic fragment of human mucin 16 (MUC16), is used to monitor the clinical progression of epithelial ovarian cancer (EOC). However, rather than simply a passive marker reflecting tumor burden, MUC16 may have a more active role by binding to immune cells and altering their tumor response. We developed a research tool to measure MUC16-binding to the surfaces of peripheral blood mononuclear cell (PBMC) subtypes and tested its research value using specimens collected serially from a woman being treated for high grade serous EOC.

Methods

Cryopreserved PBMCs were mixed with anti-CA125 antibody-labeled plasmonic gold nanoparticles (PNPs) to detect cell surface MUC16-binding along with fluorescent stains to identify B cells, NK cells, NK-T cells, T cells, and monocytes. From 3D darkfield images, a computer algorithm was applied to enumerate PNP-binding and fluorescence microscopy to identify cell lineage. Average MUC16-binding was determined by fitting a Poisson distribution to PNP-counts across similar cell types. MUC16-binding to cell types was correlated with treatment details, CA125 levels, and complete blood count (CBC) data.

Results

Over a 21-month period, monocytes had the highest level of MUC16-binding which was positively correlated with serum CA125 and inversely correlated with circulating monocyte and lymphocyte counts. Fluctuations of PNP-binding to NK cells were associated temporally with types of chemotherapy and surgical events. Levels of MUC16 bound to NK cells were positively correlated with levels of MUC16 bound to T and NK-T cells and inversely correlated with circulating platelets.

Conclusions

Assessment of MUC16-binding among cryopreserved PBMC cell types can be accomplished using darkfield and fluorescence microscopy. Correlations observed between level of binding by cell type with serum CA125, CBC data, and treatment details suggest that the new techniques may offer novel insights into EOC’s clinical course.

Significance and effects of prenatal and postnatal microbiome in the period of early individual development and options for interventional treatment

Összefoglaló. A humán mikrobiom az emberi szervezetben és az emberi testfelszínen élő mikrobaközösségek összessége, amelyek többsége a gyomor-bél rendszerben él. Ezek a mikrobaközösségek számos és sokféle baktériumot tartalmaznak, gombákat, vírusokat, archeákat és protozoonokat. Ez a mikrobiális közösség, vagy mikrobiota, a gazdaszervezetben nagyrészt egymással kölcsönösségi viszonyban tenyészik, és gondoskodik a bélben a tápanyagok anyagcseréjéről, kalibrálja az anyagcsere-működést, tanítja az immunrendszert, fenntartja a közösség integritását, és véd a kórokozók ellen. A majdan megszületendő magzat a megfelelő tápanyagellátását az anyai véráramból kapja, és így az anyai szervezetben a mikrobiota indukálta baktériumkomponensek vagy metabolitok hatékonyan átvihetők a magzatba. Az anyai mikrobiális közösségek - ideértve a praenatalis bélrendszeri, hüvelyi, száj- és bőrmikrobiomot - a terhesség alatt valójában kifejezett változásokon mennek keresztül, amelyek befolyásolhatják az egészség megőrzését, és hozzájárulhatnak a közismert betegségek kialakulásához. A magzat nem steril, és immunológiai szempontból sem naiv, hanem az anya révén környezeti ingerek hatásaitól befolyásolva kölcsönhatásba lép az anyai immunrendszerrel. Számos anyai tényező - beleértve a hormonokat, a citokineket és a mikrobiomot - módosíthatja az intrauterin környezetet, ezáltal befolyásolva a magzati immunrendszer fejlődését. A fokozott stresszben élő anyák csecsemőinél nagyobb az allergia és a gyomor-bél rendszeri rendellenességek aránya. A várandós étrendje is befolyásolja a magzati mikrobiomot a méh közvetítésével. A bélflóránk, vagyis a mikrobiom, a belünkben élő mikrobák összessége és szimbiózisa, amelynek kényes egyensúlya már csecsemőkorban kialakul, és döntően meghatározza az intestinalis barrier és a bélasszociált immunrendszer működését. A probiotikumok szaporodásához szükséges prebiotikummal is befolyásolható a bélflóra. A pre- és a probiotikum kombinációja a szimbiotikum. Az anyatej a patogénekkel szemben protektív hatású, részben azáltal, hogy emeli a Bifidobacterium-számot az újszülött bélflórájában. A dysbiosis a kommenzális, egészséges bélflóra megváltozása. Ennek szerepét feltételezik funkcionális gastrointestinalis kórképekben, egyre több pszichiátriai és neurológiai kórképben is, mint az autizmus-spektrumzavar. Orv Hetil. 2021; 162(19): 731-740. Summary. The human microbiome is the totality of microbe communities living in the human body and on the human body surface, most of which live in the gastrointestinal tract. These microbe communities contain many and varied bacteria, fungi, viruses, archaea and protozoa. This microbial community or microbiota in the host is largely reciprocal and takes care of nutrient metabolism in the gut, calibrates metabolism, teaches the immune system, maintains community integrity, and protects against pathogens. The fetus to be born is adequately supplied with nutrients from the maternal bloodstream, and thus microbial-induced bacterial components or metabolites can be efficiently transferred to the fetus in the maternal body. Maternal microbial communities, including prenatal intestinal, vaginal, oral, and dermal microbiomes, actually undergo pronounced changes during pregnancy that can affect health maintenance and contribute to the development of well-known diseases. The fetus is not sterile or immunologically naïve, but interacts with the maternal immune system through the effects of environmental stimuli through the mother. Many maternal factors, including hormones, cytokines, and the microbiome, can modify the intrauterine environment, thereby affecting the development of the fetal immune system. Infants of mothers under increased stress have higher rates of allergies and gastrointestinal disorders. The diet of the gravida also affects the fetal microbiome through the uterus. Our intestinal flora, or microbiome, is the totality and symbiosis of the microbes living in them, the delicate balance of which is established in infancy and decisively determines the functioning of the intestinal barrier and the intestinal associated immune system. The prebiotic required for the proliferation of probiotics can also affect the intestinal flora. The combination of pre- and probiotic is symbiotic. Breast milk has a protective effect against pathogens, in part by raising the number of Bifidobacteria in the intestinal flora of the newborn. Dysbiosis is a change in the commensal, healthy gut flora. Its role is hypothesized in functional gastrointestinal disorders, as well as in more and more psychiatric and neurological disorders such as the autism spectrum disorder. Orv Hetil. 2021; 162(19): 731-740.

Extracellular alpha/beta-hydrolase from Paenibacillus species shares structural and functional homology to tobacco salicylic acid binding protein 2

An alpha/ beta hydrolase annotated as a putative salicylate esterase within the genome of a species of Paenibacillus previously identified from differential and selective growth on Kraft lignin was structurally and functionally characterised. Feruloyl esterases are key to the degradation of lignin in several bacterial species and although this activity was investigated, no such activity was observed. The crystal structure of the Paenibacillus esterase, here denoted as PnbE, was determined at 1.32 Å resolution, showing high similarity to Nicotiana tabacum salicylic acid binding protein 2 from the protein database. Structural similarities between these two structures across the core domains and key catalytic residues were observed, with superposition of catalytic residues giving an RMSD of 0.5 Å across equivalent Cα atoms. Conversely, the cap domains of PnbE and Nicotiana tabacum SABP2 showed greater divergence with decreased flexibility in the PnbE cap structure. Activity of PnbE as a putative methyl salicylate esterase was supported with binding studies showing affinity for salicylic acid and functional studies showing methyl salicylate esterase activity. We hypothesise that this activity could enrich Paenibacillus sp. within the rhizosphere by increasing salicylic acid concentrations within the soil.

[The relationship between inflammatory and immunological processes during pregnancy. Practical aspects]

The aim of this review is to explore, in addition to revealing the biological background, new conceptual and therapeutic approaches for reproductive clinicians to provide better and more effective care for sterile and infertile couples. In humans, 75% of unsuccessful pregnancies are the result of failures of implantation, and implantation failure is the limiting factor for in vitro fertilization treatment. A modified "good" inflammation is necessary for implantation and parturition, but for most of pregnancy, inflammation threatens the continuation of pregnancy. During this period, maintaining the non-inflammatory condition is extremely important, enabling the maternal epigenetic effects to occur in the fetus, making it possible for the offspring to adapt as much as possible to the extrauterine life. In the maintenance of the non-inflammatory condition of pregnancy, a large amount of progesterone hormone produced by the placenta (after the luteo-placental shift) plays a crucial role. It has been reported that the role of inflammation during implantation is an ancestral response to the embryo as a foreign body. During normal pregnancy, this inflammation is initiated by the trophoblast and involves the suppression of neutrophil infiltration, the recruitment of natural killer cells to the site of implantation as well as the production of a range of proinflammatory cytokines. During the "implantation window", the uterus is primed to produce several inflammatory signals such as prostaglandin E₂ and a range of proinflammatory cytokines, including TNF, IL6 and IFNγ. The feto-placental unit is a semi-foreign graft called a "semi allograft", and the recognition of pregnancy by the mother (host) and the resulting maternal immune tolerance is an essential part of successful pregnancy and the birth of a healthy fetus. Because of the functional or absolute reduction of circulating progesterone (due to the decreasing hormone production of the physiologically "aging" placenta after around the 36th week of pregnancy) progesterone effects become insufficient. Therefore it is unable to suppress the production of IL8 and other inflammatory cytokines and the term inflammation, leading to cervical ripening, uterus contractions and parturition ("good" inflammation). Orv Hetil. 2019; 160(32): 1247-1259.

Structural basis for chain release from the enacyloxin polyketide synthase

Modular polyketide synthases and non-ribosomal peptide synthetases are molecular assembly lines that consist of several multienzyme subunits that undergo dynamic self-assembly to form a functional megacomplex. N- and C-terminal docking domains are usually responsible for mediating the interactions between subunits. Here we show that communication between two non-ribosomal peptide synthetase subunits responsible for chain release from the enacyloxin polyketide synthase, which assembles an antibiotic with promising activity against Acinetobacter baumannii, is mediated by an intrinsically disordered short linear motif and a β-hairpin docking domain. The structures, interactions and dynamics of these subunits were characterized using several complementary biophysical techniques to provide extensive insights into binding and catalysis. Bioinformatics analyses reveal that short linear motif/β-hairpin docking domain pairs mediate subunit interactions in numerous non-ribosomal peptide and hybrid polyketide-non-ribosomal peptide synthetases, including those responsible for assembling several important drugs. Short linear motifs and β-hairpin docking domains from heterologous systems are shown to interact productively, highlighting the potential of such interfaces as tools for biosynthetic engineering.

Characterization of Thiamine Diphosphate-Dependent 4-Hydroxybenzoylformate Decarboxylase Enzymes from Rhodococcus jostii RHA1 and Pseudomonas fluorescens Pf-5 Involved in Degradation of Aryl C2 Lignin Degradation Fragments

A thiamine diphosphate-dependent enzyme annotated as a benzoylformate decarboxylase is encoded by gene cluster ro02984-ro02986 in Rhodococcus jostii RHA1 previously shown to generate vanillin and 4-hydroxybenzaldehyde from lignin oxidation, and a closely related gene cluster is also found in the genome of Pseudomonas fluorescens Pf-5. Two hypotheses for possible pathways involving a thiamine diphosphate-dependent cleavage, either C-C cleavage of a ketol or diketone aryl C₃ substrate or decarboxylation of an aryl C₂ substrate, were investigated by expression and purification of the recombinant enzymes and expression of dehydrogenase and oxidase enzymes also found in the gene clusters. The ThDP-dependent enzymes showed no activity for cleavage of aryl C₃ ketol or diketone substrates but showed activity for decarboxylation of benzoylformate and 4-hydroxybenzoylformate. A flavin-dependent oxidase encoded by gene ro02984 was found to oxidize either mandelic acid or phenylglyoxal. The crystal structure of the P. fluorescens decarboxylase enzyme was determined at 1.69 Å resolution, showing similarity to structures of known benzoylformate decarboxylase enzymes. The P. fluorescens decarboxylase enzyme showed enhanced carboligase activity between vanillin and acetaldehyde, rationalized by the presence of alanine versus serine at residue 73 in the enzyme active site, which was investigated further by site-directed mutagenesis of this residue. A hypothesis for a pathway for degradation of aryl C₂ fragments arising from oxidative cleavage of phenylcoumaran and diarylpropane structures in lignin is proposed.

Sphingobacterium sp. T2 Manganese Superoxide Dismutase Catalyzes the Oxidative Demethylation of Polymeric Lignin via Generation of Hydroxyl Radical

Sphingobacterium sp. T2 contains two extracellular manganese superoxide dismutase enzymes which exhibit unprecedented activity for lignin oxidation but via an unknown mechanism. Enzymatic treatment of lignin model compounds gave products whose structures were indicative of aryl-Cα oxidative cleavage and demethylation, as well as alkene dihydroxylation and alcohol oxidation. ¹⁸O labeling studies on the SpMnSOD-catalyzed oxidation of lignin model compound guiaiacylglycerol-β-guaiacyl ether indicated that the an oxygen atom inserted by the enzyme is derived from superoxide or peroxide. Analysis of an alkali lignin treated by SpMnSOD1 by quantitative ³¹P NMR spectroscopy demonstrated 20-40% increases in phenolic and aliphatic OH content, consistent with lignin demethylation and some internal oxidative cleavage reactions. Assay for hydroxyl radical generation using a fluorometric hydroxyphenylfluorescein assay revealed the release of 4.1 molar equivalents of hydroxyl radical by SpMnSOD1. Four amino acid replacements in SpMnSOD1 were investigated, and A31H or Y27H site-directed mutant enzymes were found to show no lignin demethylation activity according to ³¹P NMR analysis. Structure determination of the A31H and Y27H mutant enzymes reveals the repositioning of an N-terminal protein loop, leading to widening of a solvent channel at the dimer interface, which would provide increased solvent access to the Mn center for hydroxyl radical generation.

Structural and functional characterisation of multi-copper oxidase CueO from lignin-degrading bacterium Ochrobactrum sp. reveal its activity towards lignin model compounds and lignosulfonate

The identification of enzymes responsible for oxidation of lignin in lignin-degrading bacteria is of interest for biotechnological valorization of lignin to renewable chemical products. The genome sequences of two lignin-degrading bacteria, Ochrobactrum sp., and Paenibacillus sp., contain no B-type DyP peroxidases implicated in lignin degradation in other bacteria, but contain putative multicopper oxidase genes. Multi-copper oxidase CueO from Ochrobactrum sp. was expressed and reconstituted as a recombinant laccase-like enzyme, and kinetically characterized. Ochrobactrum CueO shows activity for oxidation of β-aryl ether and biphenyl lignin dimer model compounds, generating oxidized dimeric products, and shows activity for oxidation of Ca-lignosulfonate, generating vanillic acid as a low molecular weight product. The crystal structure of Ochrobactrum CueO (OcCueO) has been determined at 1.1 Å resolution (PDB: 6EVG), showing a four-coordinate mononuclear type I copper center with ligands His495, His434 and Cys490 with Met500 as an axial ligand, similar to that of Escherichia coli CueO and bacterial azurin proteins, whereas fungal laccase enzymes contain a three-coordinate type I copper metal center. A trinuclear type 2/3 copper cluster was modeled into the active site, showing similar structure to E. coli CueO and fungal laccases, and three solvent channels leading to the active site. Site-directed mutagenesis was carried out on amino acid residues found in the solvent channels, indicating the importance for residues Asp102, Gly103, Arg221, Arg223, and Asp462 for catalytic activity. The work identifies a new bacterial multicopper enzyme with activity for lignin oxidation, and implicates a role for bacterial laccase-like multicopper oxidases in some lignin-degrading bacteria.

DATABASE

Structural data are available in the PDB under the accession number 6EVG.

Inhibition of D-Ala:D-Ala ligase through a phosphorylated form of the antibiotic D-cycloserine

D-cycloserine is an antibiotic which targets sequential bacterial cell wall peptidoglycan biosynthesis enzymes: alanine racemase and D-alanine:D-alanine ligase. By a combination of structural, chemical and mechanistic studies here we show that the inhibition of D-alanine:D-alanine ligase by the antibiotic D-cycloserine proceeds via a distinct phosphorylated form of the drug. This mechanistic insight reveals a bimodal mechanism of action for a single antibiotic on different enzyme targets and has significance for the design of future inhibitor molecules based on this chemical structure.

The antibiotic D-cycloserine (DCS) targets the peptidoglycan biosynthesis enzyme D-Ala-D-Ala ligase (Ddl). Here the authors reveal the DCS inhibitory mechanism by determining the structure of E. coli DdlB with a phosphorylated DCS molecule in the active site that formed in crystallo and mimics the D-alanyl phosphate intermediate.

Crystal structure of Porphyromonas gingivalis dipeptidyl peptidase 4 and structure-activity relationships based on inhibitor profiling

The Gram-negative anaerobe Porphyromonas gingivalis is associated with chronic periodontitis. Clinical isolates of P. gingivalis strains with high dipeptidyl peptidase 4 (DPP4) expression also had a high capacity for biofilm formation and were more infective. The X-ray crystal structure of P. gingivalis DPP4 was solved at 2.2 Å resolution. Despite a sequence identity of 32%, the overall structure of the dimer was conserved between P. gingivalis DPP4 and mammalian orthologues. The structures of the substrate binding sites were also conserved, except for the region called S2-extensive, which is exploited by specific human DPP4 inhibitors currently used as antidiabetic drugs. Screening of a collection of 450 compounds as inhibitors revealed a structure-activity relationship that mimics in part that of mammalian DPP9. The functional similarity between human and bacterial DPP4 was confirmed using 124 potential peptide substrates.

[Formulation possibilities of self-emulsifying drug deliv- ery systems, microemulsions and nanoemulsions.]

Objective The aim of this review is to introduce the self-emulsifying drug delivery systems which can be used to improved the bioavailability of poorly water soluble drug substances. Methods The review summarizes the most prominent results of the lipid based medicinal preparations, such as microemulsions and nanoemulsions developed in the last two decades. Results The analysis of the references details the lipid based formulation classification systems, the most common excipients, the quality attributes depending on the ingredients, as well as the differences in the characteristics of micro- and nanoemulsions. Conclusions The summary demonstrates the formulation possibilities of self-emulsifying drug delivery systems, which may increase the applicability and are promising to improve the therapeutic effectiveness.

Selective Estrogen-Receptor Modulators and Aromatase Inhibitors: Promising New Medical Therapies for Endometriosis?

Endometriosis is an estrogen-dependent disease and estrogen-related pathways are imbalanced in women with endometriosis. One of the key enzymes in estrogen synthesis is aromatase. Inhibiting this pathway at several points is a promising idea for the treatment of endometriosis. The third generation of aromatase inhibitors is becoming more potent in efficacy, with fewer side effects than previous generations, but cotreatment with other hormones is needed to inhibit ovarian stimulation. Other components that promote estrogen synthesis such as COX-2 can also be potentially targeted. Selective estrogen-receptor modulators could also be interesting in view of their tissue-specific effect. However, all these new drugs are still in an early phase of development. At present, it is too early to conclude that aromatase inhibitors, COX-2 inhibitors or selective estrogen-receptor modulators really present any added value compared with the existing drugs that can be used to achieve hormonal suppression in the medical treatment of endometriosis.

The Role of Surgery in the Management of Gestational Trophoblastic Neoplasia The Hungarian Experience

OBJECTIVE

To review the role of surgery in the management of gestational trophoblastic neoplasia (GTN) over the past 38 years in our national trophoblastic disease center.

STUDY DESIGN

Between January 1, 1977, and December 31, 2014, 371 patients with low-risk GTN and 190 patients with high-risk GTN were treated with chemotherapy, surgical interventions, or both. The indications for hysterectomy included excision of large uterine tumor masses, uterine hemorrhage or sepsis, or a drug-resistant uterine focus. Metastases were excised due to the presence of drug-resistant foci or complications of disease such as hemorrhage.

RESULTS

Over the period of 1977-2014 74 hysterectomies, 15 resections of vaginal metastases, 3 omentectomies, 13 adnexectomies, 9 lung resections, I nephrectomy, 1 lung resection and nephrectomy, and 2 craniotomies were performed among our patients. While hysterectomy was performed in 51 (26.8%) of 190 high-risk patients, hysterectomy was performed in only 23 (6.2%) of 371 low-risk patients (p < 0.01). From 1977-2006 metastases were resected in 18.3% (26/142) and from 2007-2014 in 16.7% (8/48) of high-risk patients.

CONCLUSION

In our center surgery, particularly in the form of hysterectomy, still plays a valuable role in the management of both low- and high-risk GTN.

Breech presentation: its predictors and consequences. An analysis of the Hungarian Tauffer Obstetric Database (1996-2011)

INTRODUCTION

Breech presentation is linked to abnormal pregnancy outcomes. However, the causality of this association is unknown. We aimed to investigate predictors of term breech presentation and pregnancy outcomes of breech presentation.

MATERIAL AND METHODS

Using a Hungarian registry, all term (≥ 37 weeks), singleton pregnancies with cephalic, and breech presentation in 1996-2011 were analyzed (n = 41 796). Covariates were maternal medical history and data on the present pregnancy. Multivariable logistic regression was used to investigate predictors of breech presentation and of delivery (cesarean section or other obstetrical interventions at birth) and fetal outcomes (Apgar score ≤ 7, need for perinatal intensive treatment, intrauterine death or perinatal mortality) related to breech presentation.

RESULTS

Breech presentation was independently associated with older maternal age, medical history (primiparity, stillbirth, spontaneous abortion, hormone treatment, and assisted reproduction), maternal morbidities (hypertension and oligohydramnios), and the fetal factors (female sex, younger gestational age at delivery, developmental abnormalities, small for gestational age, and birthweight). An adverse delivery outcome was 11.7 times (95% confidence interval 11.3-12.0) and an adverse fetal outcome was 1.39 times (95% confidence interval 1.33-1.45) more frequent in pregnancies with breech presentation compared with cephalic presentation. Further adjustment for predictors of breech presentation had no major effect on the delivery outcome, but it reduced the risk of adverse fetal outcome (odds ratio 1.18, 95% confidence interval 1.14-1.24).

CONCLUSIONS

Breech presentation is a marker of pathological pregnancy and is independently associated with an increased risk of gestational complications. Closer surveillance and appropriate management of pregnancies with breech presentation is warranted to prevent adverse perinatal outcomes.

Identification of Manganese Superoxide Dismutase from Sphingobacterium sp. T2 as a Novel Bacterial Enzyme for Lignin Oxidation

The valorization of aromatic heteropolymer lignin is an important unsolved problem in the development of a biomass-based biorefinery, for which novel high-activity biocatalysts are needed. Sequencing of the genomic DNA of lignin-degrading bacterial strain Sphingobacterium sp. T2 revealed no matches to known lignin-degrading genes. Proteomic matches for two manganese superoxide dismutase proteins were found in partially purified extracellular fractions. Recombinant MnSOD1 and MnSOD2 were both found to show high activity for oxidation of Organosolv and Kraft lignin, and lignin model compounds, generating multiple oxidation products. Structure determination revealed that the products result from aryl-Cα and Cα-Cβ bond oxidative cleavage and O-demethylation. The crystal structure of MnSOD1 was determined to 1.35 Å resolution, revealing a typical MnSOD homodimer harboring a five-coordinate trigonal bipyramidal Mn(II) center ligated by three His, one Asp, and a water/hydroxide in each active site. We propose that the lignin oxidation reactivity of these enzymes is due to the production of a hydroxyl radical, a highly reactive oxidant. This is the first demonstration that MnSOD is a microbial lignin-oxidizing enzyme.

Changes in the management of high-risk gestational trophoblastic neoplasia in the National Trophoblastic Disease Center of Hungary

OBJECTIVE

To compare the clinical management of patients with high-risk gestational trophoblastic neoplasia (GTN) among the periods of 1977-1990, 1991-2000, and 2001-2012 at the National Trophoblastic Disease Center of Hungary and to assess the efficacy of the FIGO 2000 staging and risk factor scoring system in comparison to the original WHO prognostic scoring system (1983).

STUDY DESIGN

We reviewed the medical records of 185 patients with high-risk GTN. From 1977-2000, patients were classified according to the original WHO prognostic scoring system (1983). From 2001-2012, high-risk patients were categorized by the FIGO 2000 system. We assessed the efficacy of MAC and EMA-CO primary combination chemotherapies. For 1977-2006 and 2007-2012 we assessed the efficacy of MAC and EMA-CO primary combination chemotherapies.

RESULTS

From 1977-1990, 63 high-risk patients (average, 4-5 patients/year), from 1991-2000, 50 high-risk patients (average, 5 patients/year), and from 2001-2012, 72 high-risk patients (average, 6 patients/year) were treated primarily with combination chemotherapy (MAC and/or EMA-CO and/or CEB). From 1977-2006, 100 high-risk patients received MAC primary combination chemotherapy and 17 cases received EMA-CO. The ratio of primary MAC primarily with and EMA-CO therapy among our high-risk patients was 5.9 (100/17) over the referred period. From 2007-2012, 21 high-risk patients were treated with primary MAC chemotherapy and 16 patients received EMA-CO. The MAC/EMA-CO ratio over this time interval was 1.3 (21/16).

CONCLUSION

We attained complete remission in 95.7% of the high-risk patients. During the last 6 years the use of EMA-CO primary combination chemotherapy increased among our high-risk patients, which has resulted in increased efficacy and fewer side effects.

Crystal structures of Trypanosoma brucei oligopeptidase B broaden the paradigm of catalytic regulation in prolyl oligopeptidase family enzymes

Oligopeptidase B cleaves after basic amino acids in peptides up to 30 residues. As a virulence factor in bacteria and trypanosomatid pathogens that is absent in higher eukaryotes, this is a promising drug target. Here we present ligand-free open state and inhibitor-bound closed state crystal structures of oligopeptidase B from Trypanosoma brucei, the causative agent of African sleeping sickness. These (and related) structures show the importance of structural dynamics, governed by a fine enthalpic and entropic balance, in substrate size selectivity and catalysis. Peptides over 30 residues cannot fit the enzyme cavity, preventing the complete domain closure required for a key propeller Asp/Glu to fix the catalytic His and Arg in the catalytically competent conformation. This size exclusion mechanism protects larger peptides and proteins from degradation. Similar bacterial prolyl endopeptidase and archael acylaminoacyl peptidase structures demonstrate this mechanism is conserved among oligopeptidase family enzymes across all three domains of life.

Structure and mechanism of acetolactate decarboxylase

Acetolactate decarboxylase catalyzes the conversion of both enantiomers of acetolactate to the (R)-enantiomer of acetoin, via a mechanism that has been shown to involve a prior rearrangement of the non-natural (R)-enantiomer substrate to the natural (S)-enantiomer. In this paper, a series of crystal structures of ALDC complex with designed transition state mimics are reported. These structures, coupled with inhibition studies and site-directed mutagenesis provide an improved understanding of the molecular processes involved in the stereoselective decarboxylation/protonation events. A mechanism for the transformation of each enantiomer of acetolactate is proposed.

Specificity determinants for lysine incorporation in Staphylococcus aureus peptidoglycan as revealed by the structure of a MurE enzyme ternary complex

Formation of the peptidoglycan stem pentapeptide requires the insertion of both l and d amino acids by the ATP-dependent ligase enzymes MurC, -D, -E, and -F. The stereochemical control of the third position amino acid in the pentapeptide is crucial to maintain the fidelity of later biosynthetic steps contributing to cell morphology, antibiotic resistance, and pathogenesis. Here we determined the x-ray crystal structure of Staphylococcus aureus MurE UDP-N-acetylmuramoyl-l-alanyl-d-glutamate:meso-2,6-diaminopimelate ligase (MurE) (E.C. 6.3.2.7) at 1.8 Å resolution in the presence of ADP and the reaction product, UDP-MurNAc-l-Ala-γ-d-Glu-l-Lys. This structure provides for the first time a molecular understanding of how this Gram-positive enzyme discriminates between l-lysine and d,l-diaminopimelic acid, the predominant amino acid that replaces l-lysine in Gram-negative peptidoglycan. Despite the presence of a consensus sequence previously implicated in the selection of the third position residue in the stem pentapeptide in S. aureus MurE, the structure shows that only part of this sequence is involved in the selection of l-lysine. Instead, other parts of the protein contribute substrate-selecting residues, resulting in a lysine-binding pocket based on charge characteristics. Despite the absolute specificity for l-lysine, S. aureus MurE binds this substrate relatively poorly. In vivo analysis and metabolomic data reveal that this is compensated for by high cytoplasmic l-lysine concentrations. Therefore, both metabolic and structural constraints maintain the structural integrity of the staphylococcal peptidoglycan. This study provides a novel focus for S. aureus-directed antimicrobials based on dual targeting of essential amino acid biogenesis and its linkage to cell wall assembly.

Evolution of substrate specificity in a recipient's enzyme following horizontal gene transfer

Despite the prominent role of horizontal gene transfer (HGT) in shaping bacterial metabolism, little is known about the impact of HGT on the evolution of enzyme function. Specifically, what is the influence of a recently acquired gene on the function of an existing gene? For example, certain members of the genus Corynebacterium have horizontally acquired a whole l-tryptophan biosynthetic operon, whereas in certain closely related actinobacteria, for example, Mycobacterium, the trpF gene is missing. In Mycobacterium, the function of the trpF gene is performed by a dual-substrate (βα)8 phosphoribosyl isomerase (priA gene) also involved in l-histidine (hisA gene) biosynthesis. We investigated the effect of a HGT-acquired TrpF enzyme upon PriA's substrate specificity in Corynebacterium through comparative genomics and phylogenetic reconstructions. After comprehensive in vivo and enzyme kinetic analyses of selected PriA homologs, a novel (βα)8 isomerase subfamily with a specialized function in l-histidine biosynthesis, termed subHisA, was confirmed. X-ray crystallography was used to reveal active-site mutations in subHisA important for narrowing of substrate specificity, which when mutated to the naturally occurring amino acid in PriA led to gain of function. Moreover, in silico molecular dynamic analyses demonstrated that the narrowing of substrate specificity of subHisA is concomitant with loss of ancestral protein conformational states. Our results show the importance of HGT in shaping enzyme evolution and metabolism.

P2-substituted N-acylprolylpyrrolidine inhibitors of prolyl oligopeptidase: biochemical evaluation, binding mode determination, and assessment in a cellular model of synucleinopathy

We have investigated the effect of regiospecifically introducing substituents in the P2 part of the typical dipeptide derived basic structure of PREP inhibitors. This hitherto unexplored modification type can be used to improve target affinity, selectivity, and physicochemical parameters in drug discovery programs focusing on PREP inhibitors. Biochemical evaluation of the produced inhibitors identified several substituent types that significantly increase target affinity, thereby reducing the need for an electrophilic "warhead" functionality. Pronounced PREP specificity within the group of Clan SC proteases was generally observed. Omission of the P1 electrophilic function did not affect the overall binding mode of three representative compounds, as studied by X-ray crystallography, while the P2 substituents were demonstrated to be accommodated in a cavity of PREP that, to date, has not been probed by inhibitors. Finally, we report on results of selected inhibitors in a SH-SY5Y cellular model of synucleinopathy and demonstrate a significant antiaggregation effect on α-synuclein.

Clinical epidemiology and management of gestational trophoblastic neoplasia in Hungary in the past 34 years

OBJECTIVE

To review our clinical experience in the treatment of patients with gestational trophoblastic neoplasia (GTN) over the past 34 years in our national trophoblastic disease center.

STUDY DESIGN

Between January 1, 1977, and December 31, 2010, 331 patients with low-risk GTN and 174 patients with high-risk GTN (altogether 505) were treated. The patients were directed to the national trophoblastic disease center from all parts of Hungary. The patients were between 14 and 54 years of age, with an average age of 28.7 years. Primary chemotherapy was selected based upon the patient's stage and prognostic score of GTN.

RESULTS

Among 237 low-risk patients, 228 (96.2%) achieved remission as a result of primary methotrexate (MTX) therapy. Out of 94 low-risk patients 90 (95.7%) achieved remission as a result of primary actinomycin-D (Act-D) therapy. MTX, Act-D and cyclophosphamide (MAC) as a primary therapy was used in 118 high-risk cases, and 110 (93.2%) patients achieved complete remission. A total of 32 high-risk patients were treated with the etoposide, high-dose MTX/folinic acid, Act-D, cyclophosphamide and vincristine (EMA-CO) regimen, and of 26 primary therapies complete remission was achieved in 21 (80.8%) cases. Primary cisplatin, etoposide and bleomycin (CEB) therapy was successful in 16 of 17 high-risk cases (94.1%). Metastases were found in 47.3% (239/505) of the patients. Hysterectomy was performed in 68 of 505 (13.5%) cases. Chemotherapy, surgical intervention or other supplementary treatments resulted in 100% remission in cases of nonmetastatic and metastatic low-risk disease. Comparison of mean prognostic scores resulted in significant differences between CEB and MAC, CEB and EMA-CO, and MAC and EMA-CO.

CONCLUSION

Our data indicate that MTX/folinic acid or Act-D should be the primary treatment in patients with nonmetastatic or metastatic low-risk GTN. Patients with high-risk metastatic GTN should be treated primarily with combination chemotherapy. Our data support the effectiveness of MAC, EMA-CO and CEB regimens. Results also show that patient care under the direction of experienced clinicians serves to optimize the opportunity for cure and minimize morbidity.

Identification and analysis of residues contained on beta --> alpha loops of the dual-substrate (beta alpha)8 phosphoribosyl isomerase A specific for its phosphoribosyl anthranilate isomerase activity

A good model to experimentally explore evolutionary hypothesis related to enzyme function is the ancient-like dual-substrate (beta alpha)(8) phosphoribosyl isomerase A (PriA), which takes part in both histidine and tryptophan biosynthesis in Streptomyces coelicolor and related organisms. In this study, we determined the Michaelis-Menten enzyme kinetics for both isomerase activities in wild-type PriA from S. coelicolor and in selected single-residue monofunctional mutants, identified after Escherichia coli in vivo complementation experiments. Structural and functional analyses of a hitherto unnoticed residue contained on the functionally important beta --> alpha loop 5, namely, Arg(139), which was postulated on structural grounds to be important for the dual-substrate specificity of PriA, is presented for the first time. Indeed, enzyme kinetics analyses done on the mutant variants PriA_Ser(81)Thr and PriA_Arg(139)Asn showed that these residues, which are contained on beta --> alpha loops and in close proximity to the N-terminal phosphate-binding site, are essential solely for the phosphoribosyl anthranilate isomerase activity of PriA. Moreover, analysis of the X-ray crystallographic structure of PriA_Arg(139)Asn elucidated at 1.95 A herein strongly implicates the occurrence of conformational changes in this beta --> alpha loop as a major structural feature related to the evolution of the dual-substrate specificity of PriA. It is suggested that PriA has evolved by tuning a fine energetic balance that allows the sufficient degree of structural flexibility needed for accommodating two topologically dissimilar substrates--within a bifunctional and thus highly constrained active site--without compromising its structural stability.

30 years' experience in the treatment of low-risk gestational trophoblastic neoplasia in Hungary

OBJECTIVE

To review the clinical experience in the treatment of patients with low-risk gestational trophoblastic neoplasia (GTN) over the past 30 years in a national trophoblastic disease center.

STUDY DESIGN

Between January 1, 1977, and December 31, 2007, 302 patients with low-risk GTN were treated. The patients were directed to our institution from all parts of Hungary. The patients were 14 to 53 years of age with an average age of 28.3 years. Methotrexate (MTX)/folinic acid or actinomycin-D (Act-D) primary chemotherapy was selected based upon the patient's stage and prognostic score of GTN.

RESULTS

Among 218 low-risk patients, 210 (96.3%) achieved remission as a result of MTX therapy. In 8 patients (3.7%), MTX-Act-D-cyclophosphamide (MAC) combination chemotherapy was needed to achieve complete remission, in some cases assisted by operation. Among 84 patients, 81 (96.4%) achieved remission as a result of Act-D therapy. In 3 cases (3.6%) complete remission was achieved by MAC combination chemotherapy. We detected metastases in 22.8% (69/302) of our low-risk patients. Chemotherapy, surgical intervention or other supplementary treatments resulted in 100% remission in cases of low-risk nonmetastatic and metastatic disease.

CONCLUSION

Our data indicate that MTX/folinic acid or Act-D should be the primary treatment in patients with nonmetastatic or metastatic low-risk GTN. Importantly, patients with resistance to single-agent chemotherapy regularly achieve complete remission with MAC combination chemotherapy. Results show that patient care under the direction of experienced clinicians serves to optimize the opportunity for cure and minimize morbidity.

Crystallization and preliminary X-ray analysis of a D-alanyl-D-alanine ligase (EcDdlB) from Escherichia coli

A recombinant form of Escherichia coli DdlB (EcDdlB) has been prepared and cocrystallized with ADP and D-alanyl-D-alanine to represent the ternary complex of EcDdlB. Furthermore, EcDdlB has been cocrystallized under the same conditions with the ligands ATP and D-alanyl-D-alanine, representing the product-inhibited complex. The crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 53.0, b = 97.6, c = 109.5 A and a = 51.2, b = 97.8, c = 110.1 A, respectively, and both contained two molecules in the asymmetric unit. Complete data sets were collected to 1.5 and 1.4 A resolution, respectively, from single crystals under cryogenic conditions using synchrotron radiation.

Increased exposure to dioxin-like compounds is associated with endometriosis in a case-control study in women

Although endometriosis is thought to be an environmental disorder initiated by dioxin exposure, this association is controversial. This study was performed to test the hypothesis that endometriosis occurs more often in women exposed to higher concentrations of dioxin-like compounds (DLC) than in those women exposed to lower concentrations. Plasma samples collected prior to laparoscopic surgery from 96 women with endometriosis and 106 control patients with a normal pelvis were measured for DLC concentrations using the dioxin-responsive chemical-activated luciferase expression bioassay. The results showed that concentration (mean+/-SD) of DLC was marginally higher in patients with endometriosis (22.3+/-9.3pg CALUX-TEQ/g lipid) than in controls (20.5+/-10.8pg). After categorization of patients in a group with 'low' plasma concentrations (<25th centile) and a group with 'high' plasma concentrations (>75th centile) of DLC, the age-adjusted odds ratio to have endometriosis was 2.44 (95% CI 1.04-5.70; P=0.04) for women with high concentrations of DLC and it increased to 3.01 (95% CI 1.06-9.04; P=0.03) when only women with moderate severe endometriosis were considered. In conclusion, women exposed to higher plasma concentrations of DLC were at higher risk of having endometriosis than women exposed to lower concentrations of DLC within normal environmental concentrations.

Quantity and quality of retrograde menstruation: a case control study

BACKGROUND

The purpose of this study was to test the hypothesis that menstruation is associated with a higher concentration of endometrial cells in peritoneal fluid(PF) and with increased white and red blood cell concentration in PF when compared to nonmenstrual phases of the cycle.

METHODS

PF was obtained at laparoscopy from 107 women with endometriosis (n = 59) and controls with a normal pelvis (n = 48) during the luteal (n = 46), follicular (n = 38) or menstrual (n = 23) phase of the cycle. Endometriosis was classified according to the classification of the American Society for Reproductive Medicine (rAFS into minimal (n = 25), mild(n = 20), moderate(n = 6) and severe(n = 8) disease. Cell counts (leucocytes, erythrocytes, thrombocytes) were determined on a cell counter. In a subset of 32 patients (13 controls and 19 women with endometriosis), PF was fixed, processed and thinlayers were prepared and stained with Papanicolaou method and with immunocytochemistry using monoclonal antibodies against cytokeratin 7(CK 7), CK 8/18, Ber-Ep4, vimentin, calretinin and CD68. Ber-Ep4 is a marker for cells with epithelial origin (in some cases for mesothelial cells as well). CD68 is specific for cells from monocyte/macrophage lineage; CK7 and CK8/18 are markers for both endometrial epithelial and mesothelial cells, whereas calretinin and vimentin are markers for both endometrial stromal and mesothelial cells.

RESULTS

In comparison with the nonmenstrual phase of the cycle, analysis of PF during menstruation showed an increased concentration of leucocytes (3.3 x 109/L vs 0.8 x 109/L, P = 0.03), erythrocytes (0.3 x 1012/L vs 0.02 x 1012/L, P = 0.006), hematocrit (0.03 L/L vs 0.003 L/L, P = 0.01) and hemoglobin (0.8 g/dL vs 0.1 g/dL, P = 0.01). Mesothelial cells stained positively with CK7, CK8/18, vimentin, and calretinin. Cells positive for Ber-Ep4 were not observed, except in 2 patients with endometriosis investigated during menses. In all patients 50-98% of single cells were strongly positive for both vimentin and CD68.

CONCLUSION

When compared to nonmenstrual phases of the cycle, menstruation is associated with an increased concentration of red and white blood cells in PF. However, the presence of EM cells that are detectable by immunohistochemistry in PF is low during all phases of the cycle, including menstruation.

Crystal structure and functional assignment of YfaU, a metal ion dependent class II aldolase from Escherichia coli K12

One of the major challenges in the postgenomic era is the functional assignment of proteins using sequence- and structure-based predictive methods coupled with experimental validation. We have used these approaches to investigate the structure and function of the Escherichia coli K-12 protein YfaU, annotated as a putative 4-hydroxy-2-ketoheptane-1,7-dioate aldolase (HpcH) in the sequence databases. HpcH is the final enzyme in the degradation pathway of the aromatic compound homoprotocatechuate. We have determined the crystal structure of apo-YfaU and the Mg (2+)-pyruvate product complex. Despite greater sequence and structural similarity to HpcH, genomic context suggests YfaU is instead a 2-keto-3-deoxy sugar aldolase like the homologous 2-dehydro-3-deoxygalactarate aldolase (DDGA). Enzyme kinetic measurements show activity with the probable physiological substrate 2-keto-3-deoxy- l-rhamnonate, supporting the functional assignment, as well as the structurally similar 2-keto-3-deoxy- l-mannonate and 2-keto-3-deoxy- l-lyxonate (see accompanying paper: Rakus, J. F., Fedorov, A. A., Fedorov, E. V., Glasner, M. E., Hubbard, B. K., Delli, J. D., Babbitt, P. C., Almo, S. C., and Gerlt, J. A. (2008) Biochemistry 47, 9944-9954). YfaU has similar activity toward the HpcH substrate 4-hydroxy-2-ketoheptane-1,7-dioate and synthetic substrates 4-hydroxy-2-ketopentanoic acid and 4-hydroxy-2-ketohexanoic acid. This indicates a relaxed substrate specificity that complicates the functional assignment of members of this enzyme superfamily. Crystal structures suggest these enzymes use an Asp-His intersubunit dyad to activate a metal-bound water or hydroxide for proton transfer during catalysis.

Diagnosis and treatment of high-risk metastatic gestational trophoblastic neoplasia in Hungary

OBJECTIVE

To review results in treatment of high-risk metastatic gestational trophoblastic neoplasia (GTN) in Hungary.

STUDY DESIGN

Between January 1, 1977, and December 31, 2006, 142 patients with high-risk metastatic GTN were treated. Patients were 14-51 years of age (average 27.9). We selected primary chemotherapy based on patient GTN stage and prognostic score.

RESULTS

Methotrexate, actinomycin-D and cyclophosphamide (MAC) as a primary therapy was used in 100 cases and as second-line chemotherapy in 6 cases. Of the 100 cases, 95 achieved complete remission. Twenty-one high-risk patients were treated with etoposide, high-dose methotrexate with folinic acid rescue, actinomycin-D, cyclophosphamide and vincristine (EMA-CO). Of 17 primary therapies, 13 patients achieved complete remission. Primary cisplatin, etoposide and bleomycin (CEB) was successful in 12 of 14 high-risk cases. Hysterectomy was performed in 42 of 142 high-risk patients; metastases were resected in 26 of 142 of high-risk patients. Comparison of mean prognostic scores resulted in significant differences between CEB and MAC, CEB and EMA-CO and MAC and EMA-CO.

CONCLUSION

Results support that patients with high-risk metastatic GTN should primarily be treated with combination chemotherapy. Our data support the effectiveness of MAC, EMA-CO and CEB regimens.

Redox-linked structural changes associated with the formation of a catalytically competent form of the diheme cytochrome c peroxidase from Pseudomonas aeruginosa

A recombinant form of the prototypic diheme bacterial cytochrome c peroxidase (BCCP) from Pseudomonas aeruginosa (PsaCCP) has been expressed in Escherichia coli and purified to homogeneity. This material was used to carry out the first integrated biochemical, spectroscopic and structural investigation of the factors leading to reductive activation of this class of enzymes. A single, tightly bound, Ca2+ ion (K = 3 x 10(10) M-1) found at the domain interface of both the fully oxidized and mixed-valence forms of the enzyme is absolutely required for catalytic activity. Reduction of the electron-transferring (high-potential) heme in the presence of Ca2+ ions triggers substantial structural rearrangements around the active-site (low-potential) heme to allow substrate binding and catalysis. The enzyme also forms a mixed-valence state in the absence of Ca2+ ions, but a combination of electronic absorption, and EPR spectroscopies suggests that under these circumstances the low potential heme remains six-coordinate, unable to bind substrate and therefore catalytically inactive. Our observations strongly suggest that the two mixed-valence forms of native PsaCCP reported previously by Foote and colleagues (Foote, N., Peterson, J., Gadsby, P., Greenwood, C., and Thomson, A. (1985) Biochem. J. 230, 227-237) correspond to the Ca2+-loaded and -depleted forms of the enzyme.

Structure and Mechanism of HpcH: A Metal Ion Dependent Class II Aldolase from the Homoprotocatechuate Degradation Pathway of Escherichia coli

Microorganisms are adept at degrading chemically resistant aromatic compounds. One of the longest and most well characterized aromatic catabolic pathways is the 4-hydroxyphenylacetic acid degradation pathway of Escherichia coli. The final step involves the conversion of 4-hydroxy-2-oxo-heptane-1,7-dioate into pyruvate and succinic semialdehyde. This reaction is catalyzed by 4-hydroxy-2-oxo-heptane-1,7-dioate aldolase (HpcH), a member of the divalent metal ion dependent class II aldolase enzymes that have great biosynthetic potential. We have solved the crystal structure of HpcH in the apo form, and with magnesium and the substrate analogue oxamate bound, to 1.6 A and 2.0 A, respectively. Comparison with similar structures of the homologous 2-dehydro-3-deoxygalactarate aldolase, coupled with site-directed mutagenesis data, implicate histidine 45 and arginine 70 as key catalytic residues.

The structure/function relationship of a dual-substrate (betaalpha)8-isomerase

Two structures of phosphoribosyl isomerase A (PriA) from Streptomyces coelicolor, involved in both histidine and tryptophan biosynthesis, were solved at 1.8A resolution. A closed conformer was obtained, which represents the first complete structure of PriA, revealing hitherto unnoticed molecular interactions and the occurrence of conformational changes. Inspection of these conformers, including ligand-docking simulations, allowed identification of residues involved in substrate recognition, chemical catalysis and conformational changes. These predictions were validated by mutagenesis and functional analysis. Arg19 and Ser81 were shown to play critical roles within the carboxyl and amino phosphate-binding sites, respectively; the catalytic residues Asp11 and Asp130 are responsible for both activities; and Thr166 and Asp171, which make an unusual contact, are likely to elicit the conformational changes needed for adopting the active site architectures. This represents the first report of the structure/function relationship of this (betaalpha)8-isomerase.

[Environmental dioxin compounds as the cause of endometriosis and other diseases]

There has been much debate of late about whether or not dioxin, an industrial toxin, could be a causative agent in the onset of endometriosis, a gynaecological disease associated with infertility and pain. Studies found either no difference in serum dioxin concentrations when cases were compared to controls or a non-significant increase, or reached low statistical power. The introductory results on Rhesus monkey contradict with the observations on mice fed with dioxin and oestrogen simultaneously. Genetic comparison shows that human belongs to the dioxin resistant races so dioxin concentrations measured in the population could not cause disease especially not an oestrogen dependent one, like endometriosis.

Endotoxins do not influence transplacental transmission of lymphotropic human herpesviruses and human papillomaviruses into amniotic fluid taken from healthy mothers before parturition in Hungary

Pregnant women were examined following healthy pregnancies at term. Amniotic fluids were sampled before arteficial rupture of membranes using closed vacutainer system. Blood samples were also taken from the pregnants simultaneously. Endotoxin concentrations of amniotic fluids were tested by the semiquantitative Limulus amebocyte lysate. Both amniotic fluids and blood samples were tested for the presence of DNA of lymphotropic human herpesviruses. The DNA of human papillomaviruses were tested only in the amniotic fluid samples. One-third of the amniotic fluids tested were found to contain measurable amounts of endotoxin. Lymphotropic herpesvirus DNA was deteced in every fourth amniotic fluid sample and in every 8th blood sample. The prevalence of papillomaviruses was 7 of 96 samples. No significant correlation was found between the presence of endotoxin and viruses in the amniotic fluids. Epstein-Barr virus, human cytomegalovirus and human herpesvirus type 7 were found more frequently in the amniotic fluids than in blood samples (7 to 1). The prevalence of human herpesvirus 6 and 8 was higher in the blood samples than that in the amniotic fluids. The mean weight of the neonates were not impaired significantly by the presence of either viruses or endotoxin. Possible post partum consequences, i.e. partial immunotolerance to viruses is discussed.

Future of endometriosis research

In women of reproductive age, health economic costs are estimated to be considerably higher for endometriosis than for conditions such as Crohn's disease, migraine and hypertension, and similar to the cost of diabetes. However, more awareness of endometriosis among patients and politicians is needed to create a better climate for research funding in the area of endometriosis in particular, and women's health in general. Recent collaboration between patients, physicians and politicians in the EU has shown that such efforts can be successful. Many arguments exist to organize the clinical care for women with advanced endometriosis in centers of excellence, but continuing education of primary-care physicians also remains a priority. New molecular techniques are resulting in new hormonal and nonhormonal targets for the noninvasive diagnosis and treatment of endometriosis. A future diagnostic serum assay might contain various elements from inflammatory serum markers to genetic/microarray/proteomics markers, owing to the multifactorial features of endometriosis.