Effects of Mutations and Ligands on the Thermostability of the l-Arginine/Agmatine Antiporter AdiC and Deduced Insights into Ligand-Binding of Human l-Type Amino Acid Transporters

The l-arginine/agmatine transporter AdiC is a prokaryotic member of the SLC7 family, which enables pathogenic enterobacteria to survive the extremely acidic gastric environment. Wild-type AdiC from Escherichia coli, as well as its previously reported point mutants N22A and S26A, were overexpressed homologously and purified to homogeneity. A size-exclusion chromatography-based thermostability assay was used to determine the melting temperatures (T_ms) of the purified AdiC variants in the absence and presence of the selected ligands l-arginine (Arg), agmatine, l-arginine methyl ester, and l-arginine amide. The resulting T_ms indicated stabilization of AdiC variants upon ligand binding, in which T_ms and ligand binding affinities correlated positively. Considering results from this and previous studies, we revisited the role of AdiC residue S26 in Arg binding and proposed interactions of the α-carboxylate group of Arg exclusively with amide groups of the AdiC backbone. In the context of substrate binding in the human SLC7 family member l-type amino acid transporter-1 (LAT1; SLC7A5), an analogous role of S66 in LAT1 to S26 in AdiC is discussed based on homology modeling and amino acid sequence analysis. Finally, we propose a binding mechanism for l-amino acid substrates to LATs from the SLC7 family.

Novel aqueous oil-in-water emulsions containing extracts of natural coniferous resins are strongly antimicrobial against enterobacteria, staphylococci and yeasts, as well as on bacterial biofilms

AIMS

The aim of this study was to examine the antimicrobial properties of novel aqueous natural rapeseed oil/saline emulsions containing different soluble components of spruce resin.

METHODS AND RESULTS

The composition of aqueous resin emulsions was analysed by GC-MS and their antimicrobial properties were studied with challenge tests and with turbidometric assays. The emulsions were strongly antimicrobial against common Gram-positive and Gram-negative bacteria (including MRSA) as well as common yeasts. Furthermore, they inhibited the biofilm formation and eradicated the microbial biofilms on tested microbes. Characteristic for the emulsions was the presence of oxidized resin acids. Other main components present in emulsions, such as lignans and coumaric acids, were not antimicrobial, when tested separately.

CONCLUSIONS

The results indicated that the oxidized resin acids were the antimicrobial components in the emulsions. Also, there appears to be a stoichiometric relationship between the number of resin acid molecules and the number microbe cells in the antimicrobial action.

SIGNIFICANCE AND IMPACT OF THE STUDY

The fact that these solutions do not contain abietic acid, which is the main allergenic compound in resins, suggests that these solutions would be suitable, well-tolerated antimicrobials for various medical applications. The aqueous formulation will also allow the expansion of the use of these emulsions in from medical applications to the food preservatives and disinfectants.

The effects of iron fortification and supplementation on the gut microbiome and diarrhea in infants and children: a review

In infants and young children in Sub-Saharan Africa, iron-deficiency anemia (IDA) is common, and many complementary foods are low in bioavailable iron. In-home fortification of complementary foods using iron-containing micronutrient powders (MNPs) and oral iron supplementation are both effective strategies to increase iron intakes and reduce IDA at this age. However, these interventions produce large increases in colonic iron because the absorption of their high iron dose (≥12.5 mg) is typically <20%. We reviewed studies in infants and young children on the effects of iron supplements and iron fortification with MNPs on the gut microbiome and diarrhea. Iron-containing MNPs and iron supplements can modestly increase diarrhea risk, and in vitro and in vivo studies have suggested that this occurs because increases in colonic iron adversely affect the gut microbiome in that they decrease abundances of beneficial barrier commensal gut bacteria (e.g., bifidobacteria and lactobacilli) and increase the abundance of enterobacteria including entropathogenic Escherichia coli These changes are associated with increased gut inflammation. Therefore, safer formulations of iron-containing supplements and MNPs are needed. To improve MNP safety, the iron dose of these formulations should be reduced while maximizing absorption to retain efficacy. Also, the addition of prebiotics to MNPs is a promising approach to mitigate the adverse effects of iron on the infant gut.

Osmosensing by the bacterial PhoQ/PhoP two-component system

The PhoQ/PhoP two-component system plays an essential role in the response of enterobacteria to the environment of their mammalian hosts. It is known to sense several stimuli that are potentially associated with the host, including extracellular magnesium limitation, low pH, and the presence of cationic antimicrobial peptides. Here, we show that the PhoQ/PhoP two-component systems of Escherichia coli and Salmonella can also perceive an osmotic upshift, another key stimulus to which bacteria become exposed within the host. In contrast to most previously established stimuli of PhoQ, the detection of osmotic upshift does not require its periplasmic sensor domain. Instead, we show that the activity of PhoQ is affected by the length of the transmembrane (TM) helix as well as by membrane lateral pressure. We therefore propose that osmosensing relies on a conformational change within the TM domain of PhoQ induced by a perturbation in cell membrane thickness and lateral pressure under hyperosmotic conditions. Furthermore, the response mediated by the PhoQ/PhoP two-component system was found to improve bacterial growth recovery under hyperosmotic stress, partly through stabilization of the sigma factor RpoS. Our findings directly link the PhoQ/PhoP two-component system to bacterial osmosensing, suggesting that this system can mediate a concerted response to most of the established host-related cues.

Protective effects of indigenous Escherichia coli against a pathogenic E. coli challenge strain in pigs

To investigate the inhibitory effect of indigenous enterobacteria on pathogenic Escherichia coli, a challenge trial with postweaning pigs was conducted. A pathogenic E. coli strain was administered to all animals and their health was closely monitored thereafter. Faecal samples were taken from three healthy and three diarrhoeic animals. Samples were cultivated on MacConkey agar and isolates were subcultured. A soft agar overlay assay was used to determine the inhibitory activity of the isolates. A total of 1,173 enterobacterial isolates were screened for their ability to inhibit the E. coli challenge strain. Colony forming units of enterobacteria on MacConkey agar were not different between healthy and diarrhoeic animals in the original samples. Furthermore, numbers of isolates per animal were also not significantly different between healthy (482 isolates) and diarrhoeic animals (691 isolates). A total of 43 isolates (3.7%) with inhibitory activity against the pathogenic E. coli challenge strain were detected. All inhibitory isolates were identified as E. coli via MALDI-TOF. The isolates belonged to the phylotypes A, C and E. Many isolates (67.4%) were commensal E. coli without relevant porcine pathogenic factors, but toxin- and fimbrial genes (stx2e, fae, estIb, elt1a, fas, fan) were detected in 14 inhibitory isolates. Healthy animals showed significantly (P=0.003) more inhibitory isolates (36 of 482 isolates; 7.5%) than diseased animals (7 of 691 isolates; 1.0%). There were no significant correlations regarding phylotype or pathogenic factors between healthy and diseased animals. This study has shown that a small proportion of indigenous E. coli is able to inhibit in vitro growth of a pathogenic E. coli strain in pigs. Furthermore, healthy animals possess significantly more inhibitory E. coli strains than diarrhoeic animals. The inhibition of pathogenic E. coli by specific indigenous E. coli strains may be an underlying principle for the containment of pathogenic E. coli in pigs.

[Epidemiological profile of uropathogenic enterobacteria producing extended spectrum beta-lactamases]

Les infections urinaires à entérobactéries productrices de bêtalactamases à spectre élargi (E-BLSE) constituent un risque infectieux, un enjeu thérapeutique de taille et peuvent même conduire dans certains cas à des impasses du fait de leur multi-résistance aux antibiotiques. Le but de ce travail est de préciser le profil épidémiologique des (E-BLSE) uropathogènes et décrire leur niveau actuel de résistance aux antibiotiques pour une meilleure prise en charge des patients selon les données locales. Il s'agit d'une étude rétrospective sur une période de trois ans (du 1^er janvier 2013 au 31 décembre 2015) concernant toutes les souches d'E-BLSE isolées de tous les ECBU traités au laboratoire de microbiologie de à l'Hôpital Militaire Moulay Ismail de Meknès. La culture a été faite selon les techniques usuelles, et l'antibiogramme a été réalisé par méthode de disque diffusion sous gélose Muller-Hinton selon les recommandations du Comité de l'antibiogramme de la Société française de microbiologie CA-SFM 2013/2014. Cette étude a permis de noter une importante prévalence globale d'isolement des E-BLSE (12.2%), particulièrement chez les patients hospitalisés (54.8%) dont la plus grande prévalence (72%) a été enregistrée dans le service d'urologie. Parmi ces E-BLSE Escherichia coli constitue la majorité (61%) des isolats, cependant au sein de la même espèce Klebsiella pneumoniae est le plus producteur de BLSE (25.8%). L'étude de l'antibioresistance des E-BLSE durant ces trois ans a mis en évidence des co-résistances à la ciprofloxacine (92.5%), au sulfametoxazole-trimethoprime (88,4%), à la gentamycine (67,2%). Globalement nos résultats sont en accord avec les données des autres pays méditerranéens exception faite pour l'amikacine dont la résistance est très basse (6.1%) dans notre étude. Cette étude a montré que la prévalence des E-BLSE en milieu hospitalier est importante et que sa diffusion en milieu communautaire est un fait préoccupant. Ces E-BLSE sont généralement résistantes aux antibiotiques, notamment des aux molécules utiles en urologie.

Multiple Antibiotic-Resistant, Extended Spectrum-β-Lactamase (ESBL)-Producing Enterobacteria in Fresh Seafood

Members of the family Enterobacteriaceae include several human pathogens that can be acquired through contaminated food and water. In this study, the incidence of extended spectrum β-lactamase (ESBL)-producing enterobacteria was investigated in fresh seafood sold in retail markets. The ESBL-positive phenotype was detected in 169 (78.60%) isolates, with Escherichia coli being the predominant species (53), followed by Klebsiella oxytoca (27), and K. pneumoniae (23). More than 90% of the isolates were resistant to third generation cephalosporins, cefotaxime, ceftazidime, and cefpodoxime. Sixty-five percent of the isolates were resistant to the monobactam drug aztreonam, 40.82% to ertapenem, and 31.36% to meropenem. Resistance to at least five antibiotics was observed in 38.46% of the isolates. Polymerase Chain Reaction (PCR) analysis of ESBL-encoding genes detected bla_CTX, bla_SHV, and bla_TEM genes in 76.92%, 63.3%, and 44.37% of the isolates, respectively. Multiple ESBL genes were detected in majority of the isolates. The recently discovered New Delhi metallo-β-lactamase gene (bla_NDM-1) was detected in two ESBL⁺ isolates. Our study shows that secondary contamination of fresh seafood with enteric bacteria resistant to multiple antibiotics may implicate seafood as a potential carrier of antibiotic resistant bacteria and emphasizes an urgent need to prevent environmental contamination and dissemination of such bacteria.

Prevalence of extended-spectrum beta-lactamase phenotypes in enterobacteria isolated from blood cultures of patients at admission to the University Hospital of Bamako

The aim of our study was to determine the frequency of extended-spectrum beta-lactamase (ESBL) phenotypes among the enterobacteria present in blood cultures of patients at admission to two university hospitals of Bamako (Mali). During a period of three months, we isolated enterobacteria from blood cultures from patients upon admission to the Point G and Gabriel Toure University Hospitals. The ESBL-positive enterobacteria were initially identified by API 20E strips and VITEK^®2 and then confirmed in France by MALDI-TOF mass spectrometry at the Bichat Hospital bacteriology laboratory. Antibiotic susceptibility was determined by the diffusion method as recommended by EUCAST. The species isolated were K. pneumoniae (14/40, 35.0 %), E. coli (11/40, 27.5 %), and E. cloacae (9/40, 22.5 %); 21/34 (61.8 %) had an ESBL phenotype, including 10/14 (71.4 %) K. pneumoniae, 8/11 (72.7 %) E. coli, and 3/9 (33 3 %), E. cloacae. The ESBL strains of K. pneumoniae, E. coli, and E. cloacae were associated, respectively, with resistance to the following antibiotics: gentamicin (10/10, 100 %; 6/8, 75%; 2/3, 67%), amikacin (2/10, 20 %; 0/8, 0%; 0/3, 0%), ofloxacin (8/10, 80. %; 7/8, 87%; 3/3, 100%), cotrimoxazole (10/10, 100 %; 6/8, 75%; 3/3, 100%). Almost two thirds (61.8%) of the enterobacteria isolated from blood cultures produced extended-spectrum beta-lactamases. They retained regular sensitivity only to carbapenems and amikacin.

VIM-1 carbapenemase-producing Escherichia coli in gulls from southern France

Acquired carbapenemases currently pose one of the most worrying public health threats related to antimicrobial resistance. A NDM-1-producing Salmonella Corvallis was reported in 2013 in a wild raptor. Further research was needed to understand the role of wild birds in the transmission of bacteria resistant to carbapenems. Our aim was to investigate the presence of carbapenem-resistant Escherichia coli in gulls from southern France. In 2012, we collected 158 cloacal swabs samples from two gull species: yellow-legged gulls (Larus michahellis) that live in close contact with humans and slender-billed gulls (Chroicocephalus genei) that feed at sea. We molecularly compared the carbapenem-resistant bacteria we isolated through culture on selective media with the carbapenem-susceptible strains sampled from both gull species and from stool samples of humans hospitalized in the study area. The genes coding for carbapenemases were tested by multiplex PCR. We isolated 22 carbapenem-resistant E. coli strains from yellow-legged gulls while none were isolated from slender-billed gulls. All carbapenem-resistant isolates were positive for bla_VIM-1 gene. VIM-1-producing E. coli were closely related to carbapenem-susceptible strains isolated from the two gull species but also to human strains. Our results are alarming enough to make it urgently necessary to determine the contamination source of the bacteria we identified. More generally, our work highlights the need to develop more bridges between studies focusing on wildlife and humans in order to improve our knowledge of resistant bacteria transmission routes.

[The clinical trials of agar and Mossel EE broth.]

The cultural diagnostic of acute intestinal infections is based on application of growth medium for selective cumulation of enterobacteria. The development of composition and technology of production of national import-substituting growth medium is an important task for supporting laboratories with high quality medical products. In the state research center of applied microbiology and biotechnology are developed and registered in established procedure a dry growth medium for selective cumulation of enterobacteria (Mossel EE broth) and dry growth medium for selective isolation and counting of enterobacteria (Mossel agar). Both media are intended for selective cumulation, isolation and counting of enterobacteria of family Enterobacteriaceae in clinical material and other objects. The comparative evaluation was applied concerning growth and inhibiting characteristics of new growth media produced by the state research center of applied microbiology and biotechnology against foreign analogues using clinical material. The total correspondence of national Mossel broth and Mossel agar to foreign analogues in case of using these media with the purpose of selective cumulation, isolation and counting of enterobacteria of family Enterobacteriaceae in clinical material and obtaining objective results of bacteriolog.

Different Flour Microbial Communities Drive to Sourdoughs Characterized by Diverse Bacterial Strains and Free Amino Acid Profiles

This work aimed to investigate whether different microbial assemblies in flour may influence the microbiological and biochemical characteristics of traditional sourdough. To reach this purpose, members of lactic acid bacteria, enterobacteria, and yeasts were isolated from durum wheat flour. Secondly, the isolated microorganisms (Pediococcus pentosaceus, Saccharomyces cerevisiae, Pantoea agglomerans, and Escherichia hermannii) were inoculated in doughs prepared with irradiated flour (gamma rays at 10 kGy), so that eight different microbial assemblies were obtained. Two non-inoculated controls were prepared, one of which (C-IF) using irradiated flour and the other (C) using non-irradiated flour. As shown by plate counts, irradiation of flour caused total inactivation of yeasts and a decrease of all the other microbial populations. However, acidification occurred also in the dough C-IF, due to metabolic activity of P. pentosaceus that had survived irradiation. After six fermentations, P. pentosaceus was the dominant lactic acid bacterium species in all the sourdoughs produced with irradiated flour (IF). Yet, IF-based sourdoughs broadly differed from each other in terms of strains of P. pentosaceus, probably due to the different microorganisms initially inoculated. Quantitative and qualitative differences of free amino acids concentration were found among the sourdoughs, possibly because of different microbial communities. In addition, as shown by culture-independent analysis (16S metagenetics), irradiation of flour lowered and modified microbial diversity of sourdough ecosystem.

Iron Fortification of Foods for Infants and Children in Low-Income Countries: Effects on the Gut Microbiome, Gut Inflammation, and Diarrhea

Iron deficiency anemia (IDA) is common among infants and children in Sub-Saharan Africa and is a leading contributor to the global burden of disease, as well as a hindrance to national development. In-home iron fortification of complementary foods using micronutrient powders (MNPs) effectively reduces the risk for IDA by ensuring that the iron needs of infants and young children are met without changing their traditional diet. However, the iron dose delivered by MNPs is high, and comparable on a mg iron per kg body weight to the supplemental doses (2 mg/kg) typically given to older children, which increases diarrhea risk. In controlled studies, iron-containing MNPs modestly increase risk for diarrhea in infants; in some cases, the diarrhea is severe and may require hospitalization. Recent in vitro and in vivo studies provide insights into the mechanism of this effect. Provision of iron fortificants to school-age children and iron-containing MNPs to weaning infants decreases the number of beneficial ‘barrier’ commensal gut bacteria (e.g., bifidobacteria), increases the enterobacteria to bifidobacteria ratio and abundances of opportunistic pathogens (e.g., pathogenic Escherichia coli), and induces gut inflammation. Thus, although iron-containing MNPs are highly effective in reducing IDA, they may increase gastrointestinal morbidity in infants, and safer formulations are needed.

Improved Phenotype-Based Definition for Identifying Carbapenemase Producers among Carbapenem-Resistant Enterobacteriaceae

A new, less restrictive definition increases detection of Klebsiella pneumoniae carbapenemase producers.

Preventing transmission of carbapenemase-producing, carbapenem-resistant Enterobacteriaceae (CP-CRE) is a public health priority. A phenotype-based definition that reliably identifies CP-CRE while minimizing misclassification of non–CP-CRE could help prevention efforts. To assess possible definitions, we evaluated enterobacterial isolates that had been tested and deemed nonsusceptible to >1 carbapenem at US Emerging Infections Program sites. We determined the number of non-CP isolates that met (false positives) and CP isolates that did not meet (false negatives) the Centers for Disease Control and Prevention CRE definition in use during our study: 30% (94/312) of CRE had carbapenemase genes, and 21% (14/67) of Klebsiella pneumoniae carbapenemase–producing Klebsiella isolates had been misclassified as non-CP. A new definition requiring resistance to 1 carbapenem rarely missed CP strains, but 55% of results were false positive; adding the modified Hodge test to the definition decreased false positives to 12%. This definition should be considered for use in carbapenemase-producing CRE surveillance and prevention.

Exudative cloacitis in the kakapo (Strigops habroptilus) potentially linked to Escherichia coli infection

AIM

To investigate the initiating causes of cloacitis (inflammation of the cloaca) in kakapo (Strigops habroptilus).

METHODS

Metagenomics using unbiased RNA or DNA sequencing was applied to faecal material from an 11-year-old female kakapo with exudative cloacitis, and a pool of eight birds (male and female aged 1-20 years) with no current signs or history of the disease. Faecal material from the diseased bird was collected pre- and post-treatment. For RNA sequencing, extracted RNA/DNA was subject to DNase, and the remaining RNA reverse transcribed to cDNA and subject to multiple displacement amplification prior to sequencing.

RESULTS

No significant alignment to any known avian virus sequence was obtained from any faecal samples. However significant BLAST alignments to five bacteriophages known to infect enterobacteria were obtained. Strong evidence was obtained for the presence of the bacteriophage Escherichia phage TL-2011b, a bacteriophage known to occur in Escherichia coli causing outbreaks of foodborne disease in humans, in the sample from the diseased bird, but not the non-diseased pool. Differences in E. coli community structure between the diseased bird and the non-diseased pool were also apparent.

CONCLUSIONS

Escherichia coli infection of human origin is suggested as a possible cause of exudative cloacitis, although confirmatory work is required to test this hypothesis.

Pink Breast Milk: Serratia marcescens Colonization

Background Breast milk can turn pink with Serratia marcescens colonization, this bacterium has been associated with several diseases and even death. It is seen most commonly in the intensive care settings. Discoloration of the breast milk can lead to premature termination of nursing. We describe two cases of pink-colored breast milk in which S. marsescens was isolated from both the expressed breast milk. Antimicrobial treatment was administered to the mothers. Return to breastfeeding was successful in both the cases. Conclusions Pink breast milk is caused by S. marsescens colonization. In such cases,early recognition and treatment before the development of infection is recommended to return to breastfeeding.

Extended-spectrum beta-lactamase-producing Enterobacteriaceae in a Malian orphanage

We show high rates of extended-spectrum beta-lactamase-producing Enterobacteriaceae carriage among the staff and children at an orphanage in Bamako, Mali. Enterobacteriaceae colonized in 100% and 63%, respectively, of the 38 children and 30 adults studied. Use of antimicrobial drugs appeared excessive and inappropriate; decontamination and hygiene protocols were also questioned.

Occurrence of yeasts, enterococci and other enteric bacteria in subgingival biofilm of HIV-positive patients with chronic gingivitis and necrotizing periodontitis

The purpose of this study was to determine the prevalence of enteric bacteria and yeasts in biofilm of 80 HIV-positive patients with plaque-associated gingivitis or necrotizing periodontitis. Patients were subjected to extra, intra oral and radiographic examinations. The oral hygiene, bleeding on probing, gingival conditions, and attachment loss were evaluated. Clinical specimens were collected from gingival crevices or periodontal pockets, transferred to VMGA III, diluted and transferred to Sabouraud Dextrose agar with 100 μg/ml of chloramphenicol, peptone water, EVA broth, EMB agar, SS agar, Bile esculin agar and Brilliant green agar. Isolation of yeasts was carried out at room temperature, for 3-7 days; and for the isolation of enteric microorganisms plates were incubated at 37°C, for 24-48 h. The yeasts identification was performed according to the carbon and nitrogen assimilation, fermentation of carbohydrates and germ tube formation. Bacteria were identified according to their colonial and cellular morphologies and biochemical tests. Yeasts were identified as Candida albicans and its occurrence was more common in patients with CD4+ below 200/mm³ and was affected by the extension of periodontal involvement (P = 0.0345). Enteric bacteria recovered from clinical specimens were identified as Enterobacter sakazakii, Enterobacter cloacae, Serratia liquefaciens, Klebsiella oxytoca and Enterococcus sp. Enterobacteriaceae and enterococci were detected in 32.5% of clinical samples from patients with necrotizing periodontitis. In conclusion, non-oral pathogenic bacteria and C. albicans were more prevalent in periodontal sites of HIV-positive patients with necrotizing periodontitis and chronic gingivitis.

Calcium carbonate phosphate binding ion exchange filtration and accelerated denitrification improve public health standards and combat eutrophication in aquatic ecosystems

Cultural eutrophication, the process by which a lake becomes rich in dissolved nutrients as a result of point and nonpoint pollutant sources, is a major cause of the loss of natural lake ecosystems throughout the world. The process occurs naturally in all lakes, but phosphate-rich nutrient runoff from sources such as storm drains and agricultural runoff is a major cause of excess phosphate-induced eutrophication. Especially in Madrona Marsh, one of the last remaining vernal marshes in the greater Los Angeles area, California, cultural eutrophication has become a major problem. In this study, calcium carbonate was found to be an excellent phosphate binder, reducing up to 70% of the phosphates in a given sample of water, and it posed relatively negligent ecological repercussions. This study involved the testing of this principle in both the laboratory and the real ecosystem. A calcium carbonate lacing procedure was first carried out to determine its efficacy in Madrona Marsh. Through this, ammonia was found to interfere with the solubility of calcium carbonate and therefore to be a hindrance to the reduction of phosphate. Therefore, various approaches for reduction of ammonia were tested, including aeration, use of fiber growth media, and plants, mainly Caulerpa verticellata, chosen for it hardiness, primarily in an attempt to increase population of Nitrobacter and Nitrosomonas. All were successful in moderately reducing ammonia levels. In addition, soil sampling, sediment analysis, microscopic plant analysis, microorganism and macroinvertebrate identification, and rate law formulations were conducted. The effect of phosphate and ammonia reduction on the populations of enterobacteria was also an important focus of this experiment. Varying concentrations of phosphate, ammonia, and calcium carbonate in conjunction with phosphate were tested in Madrona Marsh to determine their effects on the populations of enteropathogens on nonspecific blood agar, MacConkey agar, and Hektoen agar. Initial analyses suggest a strong correlation between phosphate concentrations and bacterial populations; a 66% decrease in phosphate resulted in a 35% reduction in bacterial populations and a 45% reduction in enteropathogenic populations. Likewise, a strong correlation was shown between calcium carbonate concentrations and bacterial reduction greater than that which can be attributed to the phosphate reduction alone. This was followed by the construction of various phosphate binding calcium carbonate filters, which used the ion exchange principle, including a spring loading filter, PVC pipe filter, and a galvanized filter. All were tested with the aid of Stoke's law formulation. The experiment was extremely successful in designing a working phosphate-binding and ammonia-reducing filter, and a large-scale agitator-clarifier filter system is currently being planned for construction in Madrona Marsh; this filter will reduce phosphate and ammonia levels substantially in the following years, bringing ecological, economical, and health-related improvements to the overall ecosystem and habitat.

Antimicrobial sensitivity in enterobacteria from AIDS patients, Zambia

Mycoplasma contamination of the licensed anthrax vaccine administered to military personnel has been suggested as a possible cause of Persian Gulf illness. Vaccine samples tested by nonmilitary laboratories were negative for viable mycoplasma and mycoplasma DNA and did not support its survival. Mycoplasma contamination of anthrax vaccine should not be considered a possible cause of illness.

[Hormone replacement therapy and uterine leiomyomas]

The purpose of the authors is to survey the effect that HRT has on uterine fibromas.

METHODS

It was made a very prospective one-year study on 25 women with uterine fibromas, 33-55 years old (the majority of them had subserose uterine fibromas with normal sizes). We are used the HRT with Climent and Cyclo-proginova (Schering A.G.). According to the kind of the treatment that was used, two groups were formed: the 1st had treated with Climent (n = 18) and the 2nd--with Cyclo-proginova (n = 7). The changes in the growth of the fibromas were observed with echography at the 1st, 3rd, 6th and 12th months.

RESULTS

The significant changes in the growth are absent in the 1st group, while in the 2nd group in 6 of the 7 cases showed a little increasing in the size of the fibromas (to 25 mm). However, in 2 of all women who had bleeding, were treated with abrasio residuorum, and the histological result is a simple glandular hyperplasia. The missing of important changes in the size of the fibromas can be explained with the progestogens compartment, which decreased of estrogen receptors and with the stimulating effect of the 17 beta-OH-steroiddehydrogenasis, which reduced the estradiol in the cells.

CONCLUSION

HRT could be used at women having fibromas without significant changes in the growth, under very strict control by echograpry.

[Hormone replacement therapy and uterine leiomyomas]

The purpose of the authors is to survey the effect that HRT has on uterine fibromas.

METHODS

It was made a very prospective one-year study on 25 women with uterine fibromas, 33-55 years old (the majority of them had subserose uterine fibromas with normal sizes). We are used the HRT with Climent and Cyclo-proginova (Schering A.G.). According to the kind of the treatment that was used, two groups were formed: the 1st had treated with Climent (n = 18) and the 2nd--with Cyclo-proginova (n = 7). The changes in the growth of the fibromas were observed with echography at the 1st, 3rd, 6th and 12th months.

RESULTS

The significant changes in the growth are absent in the 1st group, while in the 2nd group in 6 of the 7 cases showed a little increasing in the size of the fibromas (to 25 mm). However, in 2 of all women who had bleeding, were treated with abrasio residuorum, and the histological result is a simple glandular hyperplasia. The missing of important changes in the size of the fibromas can be explained with the progestogens compartment, which decreased of estrogen receptors and with the stimulating effect of the 17 beta-OH-steroiddehydrogenasis, which reduced the estradiol in the cells.

CONCLUSION

HRT could be used at women having fibromas without significant changes in the growth, under very strict control by echograpry.