Genome-centric metagenomic insights into the role of Chloroflexi in anammox, activated sludge and methanogenic reactors

BACKGROUND

The phylum Chloroflexi is highly abundant in a wide variety of wastewater treatment bioreactors. It has been suggested that they play relevant roles in these ecosystems, particularly in degrading carbon compounds and on structuring flocs or granules. Nevertheless, their function is not yet well understood as most species have not been isolated in axenic cultures. Here we used a metagenomic approach to investigate Chloroflexi diversity and their metabolic potential in three environmentally different bioreactors: a methanogenic full-scale reactor, a full-scale activated sludge reactor and a lab scale anammox reactor.

RESULTS

Differential coverage binning approach was used to assemble the genomes of 17 new Chloroflexi species, two of which are proposed as new Candidatus genus. In addition, we recovered the first representative genome belonging to the genus 'Ca. Villigracilis'. Even though samples analyzed were collected from bioreactors operating under different environmental conditions, the assembled genomes share several metabolic features: anaerobic metabolism, fermentative pathways and several genes coding for hydrolytic enzymes. Interestingly, genome analysis from the anammox reactor indicated a putative role of Chloroflexi in nitrogen conversion. Genes related to adhesiveness and exopolysaccharides production were also detected. Complementing sequencing analysis, filamentous morphology was detected by Fluorescent in situ hybridization.

CONCLUSION

Our results suggest that Chloroflexi participate in organic matter degradation, nitrogen removal and biofilm aggregation, playing different roles according to the environmental conditions.

Putative metabolism of Ca. Accumulibacter via the utilization of glucose

Ca. Accumulibacter was the predominant microorganism (relative FISH bio-abundance of 67 ± 5%) in a lab-scale sequential batch reactor that accomplished enhanced biological phosphorus removal (EBPR) while using glucose and acetate as the carbon sources (1:1 COD-based ratio). Both organic compounds were completely anaerobically consumed. The reactor's performance in terms of P/C ratio, phosphorous release and uptake, and overall kinetic and stoichiometric parameters were on the high end of the reported spectrum for EBPR systems (100:9.3 net mg phosphate removal per mg COD consumed when using glucose and acetate in a 1:1 ratio). The batch tests showed that, to the best of our knowledge, this is the first time a reactor enriched with Ca. Accumulibacter can putatively utilize glucose as the sole carbon source to biologically remove phosphate (COD:P (mg/mg) removal ratio of 100:6.3 when using only glucose). Thus, this research proposes that Ca. Accumulibacter directly anaerobically stored the fed glucose primarily as glycogen by utilizing the ATP provided via the hydrolysis of poly-P and secondarily as PHA by balancing its ATP utilization (glycogen generation) and formation (PHA storage). Alternative hypotheses are also discussed. The reported findings could challenge the conventional theories of glucose assimilation by Ca. Accumulibacter, and can be of significance for the biological removal of phosphorus from wastewaters with high contents of fermentable compounds or low VFAs.

Ubiquity and Diversity of Cold Adapted Denitrifying Bacteria Isolated From Diverse Antarctic Ecosystems

Nitrogen cycle has been poorly investigated in Antarctic ecosystems. In particular, how extreme conditions of low temperature, dryness, and high radiation select the microorganisms involved in the cycle is not yet understood. Denitrification is an important step in the nitrogen cycle in which nitrate is reduced stepwise to the gases NO, N2O, and N2. Denitrification is carried out by a wide group of microorganisms spread in the phylogenetic tree. The aim of this work was to isolate and characterize denitrifying bacteria present in different cold environments from Antarctica. Bacterial isolates were obtained from lake, meltwater, sea, glacier ice, ornithogenic soil, and penguin feces samples from King George Island, Fildes peninsula in the Antarctic. Samples were taken during the deicing season in five sampling campaigns. From all the samples we were able to isolate denitrifying strains. A total of 199 bacterial isolates with the capacity to grow in anaerobic mineral media reducing nitrate at 4°C were obtained. The characterization of the isolates by 16S rRNA gene sequence analysis showed a high predominance of the genus Pseudomonas, followed by Janthinobacterium, Flavobacterium, Psychrobacter, and Yersinia. Other minor genera detected were Cryobacterium, Iodobacter, Kaistella, and Carnobacterium. The capacity to denitrify was not previously described for most of the bacteria related to our isolates and in many of them denitrifying genes were not present suggesting the presence of new genes in this extreme environment. Our work demonstrates the ubiquity of denitrification in the Maritime Antarctica and gives important information linking denitrification at cold temperature with taxa in an unequivocal way.

Cognitive biases in first psychotic episode with Attention deficit and hyperactivity disorder: a controlled study

Introduction

Cognitive biases are a core feature of psychotic disorders. Moreover, people with first episode of psychosis (FEP) have more difficulties in social cognition, in particular in theory of mind. On the other hand, deficits in processing speed and distractibility appear to be core features of attention deficit hyperactivity disorder (ADHD) and impairment in these basic processes can lead to deficits in more complex functions, that could induced to cognitive biases.

Objectives

To evaluate whether FEP with and without ADHD differ in the rate and type of cognitive biases.

Methods

Participants 121 FEP treated at the Early Intervention Service of Reus and aged between 14 and 28 years. Instruments : The Diagnostic Interview for ADHD (DIVA) and the Cognitive Biases Questionnaire for Psychosis (CBQp) measuring 2 themes : anomalous perception (AP) and threatening events (TE) and 5 cognitive biases: Intentionalising (Int) , Catastrophising (Cat), Dichotomous thinking (DT), Jumping to conclusions (JTC) and Emotional reasoning (ER)

Results

31 out 121 (25.6%) met criteria for childhood ADHD. Compared with FEP ADHD- , FEP-ADHD+ presented significant higher scores in the CBQp total score (U= 2.538 ; p=0.001), the AP theme (U=2.262; p=0.02) , the TE theme (U= 2.242 ; p=0.02) and DT bias ((U= 2.188 ; p=0.03)

Conclusions

Our findings support the fact that subjects with FEP-ADHD+ presented more cognitive biases than those ADHD-. So, FEP-ADHD+ subjects could represent a clinical subgroup with a worse prognosis than FEP-ADHD ^- subjects, presenting more delusions, distress and a worse cognitive insight.

Disclosure

No significant relationships.

Database Mining to Unravel the Ecology of the Phylum Chloroflexi in Methanogenic Full Scale Bioreactors

Although microbial communities of anaerobic bioreactors have been extensively studied using DNA-based tools, there are still several knowledge gaps regarding the microbiology of the process, in particular integration of all generated data is still limited. One understudied core phylum within anaerobic bioreactors is the phylum Chloroflexi, despite being one of the most abundant groups in anaerobic reactors. In order to address the abundance, diversity and phylogeny of this group in full-scale methanogenic reactors globally distributed, a compilation of 16S ribosomal RNA gene sequence data from 62 full-scale methanogenic reactors studied worldwide, fed either with wastewater treatment anaerobic reactors (WTARs) or solid-waste treatment anaerobic reactors (STARs), was performed. One of the barriers to overcome was comparing data generated using different primer sets and different sequencing platforms. The sequence analysis revealed that the average abundance of Chloroflexi in WTARs was higher than in STARs. Four genera belonging to the Anaerolineae class dominated both WTARs and STARs but the core populations were different. According to the phylogenetic analysis, most of the sequences formed clusters with no cultured representatives. The Anaerolineae class was more abundant in reactors with granular biomass than in reactors with disperse biomass supporting the hypothesis that Anaerolineae play an important role in granule formation and structure due to their filamentous morphology. Cross-study comparisons can be fruitfully used to understand the complexity of the anaerobic digestion process. However, more efforts are needed to standardize protocols and report metadata information.

Autosomal recessive hypotrichosis with loose anagen hairs associated with TKFC mutations

BACKGROUND

Loose anagen hair is a rare form of impaired hair anchorage in which anagen hairs that lack inner and outer root sheaths can be gently and painlessly plucked from the scalp. This condition usually occurs in children and is often self-limiting. A genetic basis for the disorder has been suggested but not proven. A better understanding the aetiology of loose anagen hair may improve prevention and treatment strategies.

OBJECTIVES

To identify a possible genetic basis of loose anagen hair using next-generation DNA sequencing and functional analysis of variants identified.

METHODS

In this case study, whole-exome sequencing analysis of a pedigree with one affected individual with features of loose anagen hair was performed.

RESULTS

The patient was found to be compound heterozygous for two single-nucleotide substitutions in TKFC resulting in the following missense mutations: c.574G> C (p.Gly192Arg) and c.682C> T (p.Arg228Trp). Structural analysis of human TKFC showed that both mutations are located near the active site cavity. Kinetic assays of recombinant proteins bearing either of these amino acid substitutions showed almost no dihydroxyacetone kinase or D-glyceraldehyde kinase activity, and FMN cyclase activity reduced to just 10% of wildtype catalytic activity.

CONCLUSIONS

TKFC missense mutations may predispose to the development of loose anagen hairs. Identification of this new biochemical pathobiology expands the metabolic and genetic basis of hypotrichosis.

Commercial formulation amendment transiently affects the microbial composition but not the biogas production of a full scale methanogenic UASB reactor

The treatment of dairy wastewater in methanogenic reactors cause several problems due to their high lipid content. One strategy to overcome these problems is the use of commercial formulations. Here we studied the effect of adding a commercial formulation, designed to improve fat degradation, on both the microbial community composition and reactor performance. Samples from two full-scale Up-flow Anaerobic Sludge Blanket (UASB) reactors in parallel arrangement were analysed. The commercial product was added to one of the reactors while the other was used as control. The amendment increased significantly the fat removal but an accumulation of volatile fatty acids was detected. Nevertheless, no significant differences were observed in the total Chemical Oxygen Demand (COD) removal and biogas production between reactors. A significant change in the bacterial community was not detected by 16S rRNA gene Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis probably due to the limitation of the technique. A strong change in the composition of the phylum Firmicutes was detected with 16S rRNA gene amplicon sequencing; however, it didn't persist during the whole operation period. The relative abundance of minor Operational Taxonomic Units (OTUs) with sequences related to syntrophic bacteria increased with the amendment. Although a better hydrolytic capacity was obtained when adding the commercial product, the overall process did not improve and no increase in biogas production was detected. Alternative strategies could be applied to avoid the accumulation of intermediary products and improve biogas production as intermittent addition of the commercial product or batch operation of reactors.

Targeted Cell Sorting Combined With Single Cell Genomics Captures Low Abundant Microbial Dark Matter With Higher Sensitivity Than Metagenomics

Rare members of environmental microbial communities are often overlooked and unexplored, primarily due to the lack of techniques capable of acquiring their genomes. Chloroflexi belong to one of the most understudied phyla, even though many of its members are ubiquitous in the environment and some play important roles in biochemical cycles or biotechnological applications. We here used a targeted cell-sorting approach, which enables the selection of specific taxa by fluorescent labeling and is compatible with subsequent single-cell genomics, to enrich for rare Chloroflexi species from a wastewater-treatment plant and obtain their genomes. The combined workflow was able to retrieve a substantially higher number of novel Chloroflexi draft genomes with much greater phylogenetical diversity when compared to a metagenomics approach from the same sample. The method offers an opportunity to access genetic information from rare biosphere members which would have otherwise stayed hidden as microbial dark matter and can therefore serve as an essential complement to cultivation-based, metagenomics, and microbial community-focused research approaches.

Preliminary analysis of Chloroflexi populations in full-scale UASB methanogenic reactors

AIMS

The phylum Chloroflexi is frequently found in high abundance in methanogenic reactors, but their role is still unclear as most of them remain uncultured and understudied. Hence, a detailed analysis was performed in samples from five up-flow anaerobic sludge blanket (UASB) full-scale reactors fed different industrial wastewaters.

METHODS AND RESULTS

Quantitative PCR show that the phylum Chloroflexi was abundant in all UASB methanogenic reactors, with higher abundance in the reactors operated for a long period of time, which presented granular biomass. Both terminal restriction fragment length polymorphism and 16S rRNA gene amplicon sequencing revealed diverse Chloroflexi populations apparently determined by the different inocula. According to the phylogenetic analysis, the sequences from the dominant Chloroflexi were positioned in branches where no sequences of the cultured representative strains were placed. Fluorescent in situ hybridization analysis performed in two of the reactors showed filamentous morphology of the hybridizing cells.

CONCLUSIONS

While members of the Anaerolineae class within phylum Chloroflexi were predominant, their diversity is still poorly described in anaerobic reactors. Due to their filamentous morphology, Chloroflexi may have a key role in the granulation in methanogenic UASB reactors.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results bring new insights about the diversity, stability, dynamics and abundance of this phylum in full-scale UASB reactors which aid in understanding their function within the reactor biomass. However, new methodological approaches and analysis of bulking biomass are needed to completely unravel their role in these reactors. Combining all this knowledge with reactor operational parameters will allow to understand their participation in granulation and bulking episodes and design strategies to prevent Chloroflexi overgrowth.

Geobacter, Anaeromyxobacter and Anaerolineae populations are enriched on anodes of root exudate-driven microbial fuel cells in rice field soil

Plant-based sediment microbial fuel cells (PMFCs) couple the oxidation of root exudates in living rice plants to current production. We analysed the composition of the microbial community on anodes from PMFC with natural rice field soil as substratum for rice by analysing 16S rRNA as an indicator of microbial activity and diversity. Terminal restriction fragment length polymorphism (TRFLP) analysis indicated that the active bacterial community on anodes from PMFCs differed strongly compared with controls. Moreover, clones related to Deltaproteobacteria and Chloroflexi were highly abundant (49% and 21%, respectively) on PMFCs anodes. Geobacter (19%), Anaeromyxobacter (15%) and Anaerolineae (17%) populations were predominant on anodes with natural rice field soil and differed strongly from those previously detected with potting soil. In open circuit (OC) control PMFCs, not allowing electron transfer, Deltaproteobacteria (33%), Betaproteobacteria (20%), Chloroflexi (12%), Alphaproteobacteria (10%) and Firmicutes (10%) were detected. The presence of an electron accepting anode also had a strong influence on methanogenic archaea. Hydrogenotrophic methanogens were more active on PMFC (21%) than on OC controls (10%), whereas acetoclastic Methanosaetaceae were more active on OC controls (31%) compared with PMFCs (9%). In conclusion, electron accepting anodes and rice root exudates selected for distinct potential anode-reducing microbial populations in rice soil inoculated PMFC.

Global impact and application of the anaerobic ammonium-oxidizing (anammox) bacteria

In the anaerobic ammonium oxidation (anammox) process, ammonia is oxidized with nitrite as primary electron acceptor under strictly anoxic conditions. The reaction is catalysed by a specialized group of planctomycete-like bacteria. These anammox bacteria use a complex reaction mechanism involving hydrazine as an intermediate. The reactions are assumed to be carried out in a unique prokaryotic organelle, the anammoxosome. This organelle is surrounded by ladderane lipids, which make the organelle nearly impermeable to hydrazine and protons. The localization of the major anammox protein, hydrazine oxidoreductase, was determined via immunogold labelling to be inside the anammoxosome. The anammox bacteria have been detected in many marine and freshwater ecosystems and were estimated to contribute up to 50% of oceanic nitrogen loss. Furthermore, the anammox process is currently implemented in water treatment for the low-cost removal of ammonia from high-strength waste streams. Recent findings suggested that the anammox bacteria may also use organic acids to convert nitrate and nitrite into dinitrogen gas when ammonia is in short supply.

Post-treatment of a slaughterhouse wastewater: stability of the microbial community of a sequencing batch reactor operated under oxygen limited conditions

Slaughterhouse wastewater is a complex effluent with an important content of organic nitrogen. After an anaerobic treatment where most of the organic matter is removed, the nitrogen, remains as ammonium and post-treatment of the effluent is necessary. Sequencing batch reactor (SBR) technology has been developed to completely remove nitrogen in one single reactor combining aerobic and anoxic stages. Under oxygen limited conditions only nitrite is produced with concomitant energy saving. The stability and diversity of the microbial community from a nitrifying denitrifying SBR operated under oxygen limited conditions were studied using molecular and respirometric methods. The AOB (ammonia oxidizing bacteria) community was relatively stable Nitrosomonas being the dominant genera although Nitrosospira and Nitrosococcus were detected in low proportions. Nitrite oxidizing bacteria were out competed during the operation under oxygen-limited conditions. After an increase of the DO in the reactor Nitrobacter spp were detected suggesting that they remained in the system. Changes in the AOB and denitrifying communities were observed after the DO increase. Sedimentation problems were detected during operation, this could be related to the predominance of Thauera spp detected by FISH and T-RFLP.

Sequencing batch reactor as a post-treatment of anaerobically treated dairy effluent

Wastewater from dairy industries, characterized by its high COD content and relative high COD/TKN ratio, requires post-treatment after anaerobic treatment to complete the removal of organic matter and nutrients. Due to its simplicity, robustness and low maintenance costs, sequencing batch reactors (SBR) result in an attractive system, especially in case of small dairy industries in order to comply with the emission standards. The goal of this work was to determine the operational parameters, optimize the performance, and study the stability of the microbial population of a SBR system for the post-treatment of an anaerobic pond effluent. High and stable removal of COD and TKN was achieved in the reactor, which can easily be set up in dairy industries. An active nitrifying population was selected during reactor operation and maintained relatively stable, while the heterotrophic (total and denitrifying) communities were more unstable and susceptible to changes in the operating conditions.

[Steroid-responsive nephrotic syndrome in IgA nephropathy]

A 46-year-old male, smoker of half a packet a day and an alcohol intake of 80 grams a day, with an unremarkable medical history, was referred to our service in the year 1988 for a study of nephrotic syndrome. He presented normal renal function, without either microhematuria nor hypertension. In blood analysis an albuminemia of 10 g/l and proteinuria of 22 g/d was observed. A first renal biopsy was carried out which indicated minimal change disease. Steroid treatment was started, as a result the nephrotic syndrome disappeared and the blood analysis normalized. Later he had 4 new outbreaks, all of them steroid-responsive. In 1992 a second renal biopsy was performed after the fourth outbreak and the presence of mild renal failure, that this time indicated a IgA nephropathy. Steroid treatment was tried again, and this time cyclophosphamide was added to try to reduce steroid doses. This result in normalization of renal function and decrease of proteinuria to 2 g/d. The patient remained stable until 1996 when the fifth outbreak occurred, again with mild renal failure and proteinuria in nephrotic range. Therefore a third renal biopsy was performed, that confirmed the presence of IgA nephropathy, but now with signs of histological progression of the disease. Following this, he presented five outbreaks in 3 years, all of them steroid-responsive, with decrease of proteinuria although without renal function normalization. In the year 2000, at his tenth outbreak of nephrotic syndrome it was decided to add cyclosporine to the steroid treatment, achieving the stability of the patient, without further outbreaks until now, with proteinuria of 1.6 g/d and C. creat. 59 ml/min.

Evolution of the bacterial community during granules formation in denitrifying reactors followed by molecular, culture-independent techniques

The microbial community in two acetate-fed denitrifying reactors, inoculated with methanogenic sludge, was monitored by 16S rDNA-based methods (SSCP and FISH). Both reactors converged to similar, stable communities. The predominant organisms belonged to the genera Thauera, Paracoccus and Denitrobacter, detected both by molecular and culture-based methods.

Sludge bed development in denitrifying reactors using different inocula-performance and microbiological aspects

Aerobic and methanogenic consortia were evaluated as inocula for laboratory scale denitrifying reactors, fed with a synthetic wastewater with acetate as the main electron donor. The denitrifying microflora of inocula and reactors was evaluated by specific denitrifying activity, enumeration and isolation of denitrifiers, which were screened by amplified ribosomal DNA restriction analysis. Reactor performance was monitored by COD and nitrate removal efficiencies and granule size. The aerobic sludge failed to form granules, probably due to the development of a filamentous, nitrate-reducing organism which was characterised by 16SrDNA sequencing as Bacillus cereus. The methanogenic sludge showed denitrifying activity and adapted very rapidly to denitrifying conditions in the two reactors seeded with granules of different sizes. Denitrifiers grew around the granules, increasing the specific denitrifying activity of the sludge over 10-fold. Exopolymer-forming organisms, belonging to the same species, were isolated from both reactors. Granule size increased during operation, but flotation of the aggregates, related to gas retention was observed.

Purification, characterization, and substrate and inhibitor structure-activity studies of rat liver FAD-AMP lyase (cyclizing): preference for FAD and specificity for splitting ribonucleoside diphosphate-X into ribonucleotide and a five-atom cyclic phosphodiester of X, either a monocyclic compound or a cis-bicyclic phosphodiester-pyranose fusion

An enzyme with FAD-AMP lyase (cyclizing) activity, splitting FAD to AMP and riboflavin 4',5'-phosphate (cFMN), was recently identified [Fraiz, F., et al. (1998) Biochem. J. 330, 881-888]. Now, it has been purified to apparent homogeneity from a rat liver supernatant, by a procedure that includes affinity for ADP-agarose (adsorption required the activating cation Mn2+ and desorption required its removal), to a final activity of 2.2 units/mg after a 240-fold purification with a 15% yield. By SDS-PAGE, only one protein band was observed (Mr = 59 000). The correspondence between protein and enzyme activity was demonstrated by renaturation after SDS-PAGE, by gradient ultracentrifugation followed by analytical SDS-PAGE, and by native PAGE with visualization of enzyme activity by fluorescence. A native Mr of 100 000 (ultracentrifugation) or 140 000 (gel filtration) indicated that FAD-AMP lyase could be a dimer. The enzyme required millimolar concentrations of Mn2+ or Co2+, exhibited different optimum pH values with these cations (pH 8.5 or 7.3, respectively), and was strongly inhibited by ADP or ATP, but not by dADP, dATP, or the reaction products AMP and cFMN. A specificity study was conducted with 35 compounds related to FAD, mostly nucleoside diphosphate-X (NDP-X) derivatives. Besides FAD, the enzyme split 11 of these compounds with the pattern NDP-X --> NMP + P=X. Structure-activity correlations of substrates, nonsubstrates, and inhibitors, and the comparison of the enzymic reactivities of NDP-X compounds with their susceptibilities to metal-dependent chemical degradation, pinpointed the following specificity pattern. FAD-AMP lyase splits ribonucleoside diphosphate-X compounds in which X is an acyclic or cyclic monosaccharide or derivative bearing an X-OH group that is able to attack internally the proximal phosphorus with the geometry necessary to form a P=X product, either a five-atom monocyclic phosphodiester or a cis-bicyclic phosphodiester-pyranose fusion. For instance, NDP-glucose and GDP-alpha-L-fucose were substrates, but dTDP-glucose, NDP-mannose, and GDP-beta-L-fucose were not. Judging from kcat/Km ratios, we found the best substrate to be FAD, followed closely by ADP-glucose (kcat/Km only 2-fold lower, but not a physiological compound in mammals), whereas other substrates exhibited 50-500-fold lower kcat/Km values. However, there was no evidence for specific flavin recognition. Instead, what seems to be recognized is the NDP moiety of NDP-X, with a strong preference for ADP-X. Splitting would then depend on the presence of an adequate X-OH group. The possibility that, besides FAD, there could be in mammals other ADP-X substrates of FAD-AMP lyase is discussed, with emphasis placed on some ADP-ribose derivatives.

Enzymic formation of riboflavin 4',5'-cyclic phosphate from FAD: evidence for a specific low-Km FMN cyclase in rat liver1

An enzyme activity splitting FAD to AMP and riboflavin 4',5'-cyclic phosphate (4',5'-cFMN), with a Km of 6-8 microM, was partially purified from the cytosolic fraction of rat liver homogenates. 4', 5'-cFMN was characterized by enzyme, HPLC, UV-visible and NMR spectroscopic analyses. The data suggest that a novel enzyme, tentatively named FAD-AMP lyase (cyclizing) or FMN cyclase, is involved. Also, 4',5'-cFMN was hydrolysed to 5'-FMN by a rat liver cyclic phosphodiesterase. The results indicate a novel enzymic pathway for flavins in mammals, and support the biological relevance of 4',5'-cFMN, perhaps as a flavocoenzyme or a regulatory signal.

[Chylopericardium after acute pericarditis]

We present an 18 year-old man with chylopericardium after acute pericarditis with severe pericardial effusion and cardiac tamponade secondary to Mycoplasma pneumoniae infection. We review the etiology, diagnostic procedures and therapeutic possibilities for chylopericardium.

Immunological aspects of a case of posttransplant lymphoproliferative disorder

We describe a female renal transplant recipient with cytomegalovirus and Epstein-Barr virus (EBV) infections who developed aggressive polymorphous polyclonal B cell proliferation. She received two courses of OKT3. We found a majority of transformed B cells bearing EBV membrane receptor CR2 and EBV nuclear antigen. Posttransplant lymphoproliferative disorders may be associated with a significant immunological activation, detected in this case by the sudden increase of beta 2-microglobulin and immunoglobulin levels, including immunoglobulin D. These raised levels persisted throughout the short and rapid course of the disease.

Heterogeneous pituitary secretion in familial hypogonadotropic hypogonadism

Dynamic testing of the hypothalamic pituitary system in familial hypogonadotropic hypogonadism has suggested the possibility of a central nervous disorder associated with variable pituitary secretory secretion. In order to investigate this issue further 7 patients of two families were studied. Male patients exhibited two types of FSH responses to LHRH administration. Two patients had a small response, and the other exhibited a normal response. The LH response was absent or small in both male and female patients. One month therapy with daily injections of LHRH did not improve pituitary responsiveness to a second LHRH test. Estrogen treatment given to females during one month had no improvement effect on another LHRH test. Estradiol benzoate produced a surge in both LH and FSH in half of patients tested which is surprising in the presence of a previous clomiphene negative response. Two of four women had elevated prolactin levels which increased defectuously after metoclopramide administration which could suggest an abnormal hypothalamic status. On the basis of these results it seems that familial hypogonadotropism is originated by an abnormality at two levels, the anterior pituitary and the hypothalamus as well.

Induction of ovulation with clomiphene and estradiol benzoate in anovulatory women refractory to clomiphene alone

Twenty-two infertile and clomiphene-nonresponding patients received a course of clomiphene, 100 mg/day for 5 days, followed 7 days later by an intramuscular injection of 1 mg of estradiol benzoate. The diagnosis of idiopathic chronic anovulation had been established. None of these patients had galactorrhea, hirsutism, or ovarian enlargement. Thirteen of the twenty-two women had surges of both luteinizing hormone and follicle-stimulating hormone after the estradiol injection; the peak gonadotropin levels occurred within 72 hours of the injection. These 13 patients ovulated and pregnancy ensued in 10 of them. The estradiol benzoate injection also elicited a significant increase in serum prolactin levels- This enhanced prolactin release had no apparent effect on the gonadotropin surge. These results suggest that the association of clomiphene and estradiol benzoate potentiates the action of clomiphene and may prove useful in clomiphene nonresponders.

Gonadotropic responsiveness to clomiphene, LRH, estradiol, and bromocriptine in galactorrheic women

Twenty hyperprolactinemic patients with galactorrhea were studied to determine their gonadotropic responses to various stimuli. Five women lacked response to gonadotropin following the administration of clomiphene citrate. Ten patients who had luteinizing hormone releasing hormone (LRH) tests before and during bromocriptine administration exhibited varied FSH and LH responses that apparently were unaffected by bromocriptine therapy. A loss of the normal positive feedback of estrogens at the level of the hypothalamus was demonstrated in most patients before and during bromocriptine therapy. Long-term treatment with bromocriptine in 11 women resulted in a decrease of serum prolactin, cessation of lactation in all, and pregnancy in 8. These results suggest that the failure of normal secretion of gonadotropins in hyperprolactinemic women may result from 1) inadequate release of endogenous LRH, and 2) loss of the positive feedback of estrogens, as a result of the same hypothalamic disturbance that provokes the hyperprolactinemia. In turn, the elevated prolactin levels may exert a short-loop negative feedback at the hypothalamic level, inhibiting cyclic gonadotropin release.