Micrococci in the skin microbiocenosis of the breasts. Ecologic characteristics of the colony

The ecological characteristics of the micrococcal community on the skin of the mammary glands of nulligravidae, pregnant and puerperant women have been studied. The species composition of the community, the population size and occurrence of each species, its participation in the dominant structure of the community have been determined. The comparative evaluation of its types has been made. A decrease in the dominating role of M. luteus in pregnant and puerperant women has been established. The tendency towards the normalization of the structure of the community in the postnatal period has been established.     

Temporal study of the staphylococci and micrococci of normal infant skin

Staphylococcus and Micrococcus populations were collected from the healthy skin of 10 infant subjects. Infants were sampled from 1 day to 32 weeks of age. Species were characterized by approximately 30 different morphological, physiological, and biochemical characters. Staphylococci were the predominant inhabitants of normal skin, whereas micrococci were found only occasionally in this environment. Staphylococcus epidermidid, S. haemolyticus, and S. hominis were the predominant and persistent staphylococci. These species constituted a high percentage of the total aerobic bacterial flora of infant skin. Micrococcus luteus and M. kristinae were the prevalent micrococci found on infant skin. Only limited correlation between Staphyloccus and Micrococcus populations and infant age or body area sampled was indicated by this study.     

Temporal study of the staphylococci and micrococci of normal infant skin.

Staphylococcus and Micrococcus populations were collected from the healthy skin of 10 infant subjects. Infants were sampled from 1 day to 32 weeks of age. Species were characterized by approximately 30 different morphological, physiological, and biochemical characters. Staphylococci were the predominant inhabitants of normal skin, whereas micrococci were found only occasionally in this environment. Staphylococcus epidermidid, S. haemolyticus, and S. hominis were the predominant and persistent staphylococci. These species constituted a high percentage of the total aerobic bacterial flora of infant skin. Micrococcus luteus and M. kristinae were the prevalent micrococci found on infant skin. Only limited correlation between Staphyloccus and Micrococcus populations and infant age or body area sampled was indicated by this study.     

Population dynamics and antagonistic potential of enterococci colonizing the phyllosphere of grasses

AIMS: To investigate the spatial and temporal dynamics of enterococci colonizing forage grass and their ability to produce bacteriocins. Methods and RESULTS: Enterococci could be detected on above-ground plant parts throughout the growing season, with high continuity but low cell numbers (2.60 x 101-6.16 x 104 cfu g-1 fresh matter). A total of 750 strains were isolated and identified by their whole-cell protein patterns as Enterococcus faecalis (7.9%), Ent. mundtii (7.9%), Ent. casseliflavus (5.5%), Ent. faecium (5.2%) and Ent. sulfureus (0.1%). The vast majority of the strains (69.7%) formed a homogeneous 16S rDNA genotype that differed from those of known enterococci. A screening for antagonistic activity using an agar spot test revealed that 18.4% of all isolates were potential antagonists. Partially-purified proteins extracted from cell-free culture supernatant fluids of various species were characterized as pH- and heat-stable bacteriocins active against a wide range of lactic acid bacteria, clostridia and Listeria. The producing strains were antagonistically active even on 'phylloplane agar' at temperatures between 4 and 37 degrees C. CONCLUSION: Enterococci are a common part of the epiphytic microflora of grasses, displaying probably some antagonistic activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The results provide new information on the distribution, species diversity and antagonistic potential of enterococci in the phyllosphere.     

Staphylococci in skin microbiocenosis of the breasts in healthy women

The autoflora of different anatomical regions of the mammary glands in 120 healthy nulliparous women aged 18-24 years was studied by P. Williamson and A. M. Kligler's methods of smears and washings. From the nipple, the areola, and the adjacent region of the skin 2,248 strains of anaerobic microorganisms were isolated; of these, 63.83% were staphylococci and micrococci, 6.01% were streptococci, 1.91% were Neisseria, 17.79% were Corynebacterium, 3.87% were bacilli, 2.8% were enterobacteria, and 3.79% were fungi. Coagulase-positive staphylococci occurred in 1.56% of cases. Out of 11 coagulase-negative species of this genus, S. epidermidis occurred most frequently on the skin of the mammary glands. The nipple was found to have the highest bacterial contamination (0.55 X 10(6) +/- 0.7 X 10(5) cells/sq. cm for the right mamma and 0.59 X 10(6) +/- 0.7 X 10(5) cells/sq. cm for the left mamma) and the skin adjacent the areola, the lowest bacterial contamination (0.14 X 10(4) +/- 0.2 X 10(3) cells/sq. cm for the right mamma and 0.25 X 10(4) +/- 0.3 X 10(3) cells/sq. cm for the left mamma). P. Williams and A. M. Kligman's method of washings, more accurate and informative, was found to be preferable for the study of the quantitative characteristics of the dermal microbiocenosis of the mammary glands.     

Staphylococci in skin microbiocenosis of the breasts in nursing women

The levels of the bacterial contamination of the nipple, the areola and the surrounding skin, the occurrence and species composition of staphylococci in 120 nursing women on days 4-5 after parturition have been studied. S. aureus contaminate the surface of the nipple and the areola in 75% of the examined women, and in 57.5% of these women the massive contamination of the above-mentioned areas (greater than or equal to 10(3) colony-forming units per sq. cm) is observed. In 80% of puerperae the occurrence of S. epidermidis on the nipple, the areola and the surrounding skin has proved to be practically the same. The population of S. aureus colonizing the mammary glands consists mainly of hospital strains; of these, 75.97% belong to phage type 75.     

Staphylococci in the skin microbiocenosis of the breasts in pregnant women

The microflora of the mammary glands in the area of the nipple, the areola and the adjacent skin was studied by the methods of washings and impression. 120 nonpregnant women and 164 pregnant women were examined. The pregnant women showed a higher level of the contamination of the above-mentioned sites. The highest density of bacterial population was detected in the area of the nipple and the lowest density, on the skin surrounding the areola. Coagulase-negative staphylococci proved to be the most numerous organisms among all bacterial population found on the skin of the mammary glands of pregnant women. Of these staphylococci, S. epidermidis was most frequently isolated, its isolation rate being higher in the pregnant women than in the nonpregnant ones.     

Structural characteristics and biological properties of Pseudomonas fluorescens lipopolysaccharides

The structure and biological properties of lipopolysaccharides (LPSs) from strains IMB 4125 (=ATCC 13525) and IMB 7769 of the bacterium Pseudomonas fluorescens (biovar I) were studied in vitro. LPSs were similar in the composition of lipid A and the core lipid but differed in the structure of O-specific polysaccharide chains, which was corroborated by the absence of serological relationships between them. The toxicity (LD50) of LPSs of P. fluorescens with respect to D-glucosamine-sensitized mice was 40-50 times lower than the toxicity of the classic endotoxins, LPSs of E. coli. The LPSs studied stimulated the production of tumor necrosis factor (TNF) and nitric oxide (NO) by mouse peritoneal macrophages. The rates of TNF and NO synthesis induced by the LPSs of interest were eight to nine and three to five times lower, respectively, than the corresponding parameters of the control LPSs of E. coli 055:B5 and 026:B6. Additionally, LPS preparations of the P. fluorescens strains induced TNF synthesis by monocytes of human whole-blood preparations. Certain differences in biological properties of these strains have been revealed, which could be due to the characteristic features of LPS structure and composition in different cultures.     

The adhesive and colonizing properties of Aerococcus viridans]

On the basis of experiments carried out in the course of this study the conclusion can be made that one of the mechanisms of the preventive effect of aerococci, the representatives of the indigenous microflora of the gastrointestinal tract, lies in their capacity for adhesion to and colonization of the mucous membrane, this enhancing the resistance of the enteric tract to infections. These properties of anterococci substantiate good prospects of using M-bacterin (live lyophilized aerococcal culture) for the control of enteric infections and dysbacteriosis.     

Population genetics of colonizing success of weedy rye in Northern California

Summary Genetic parameters of 11 weedy rye populations located in California's northern mountain area and the adjoining Oregon border were compared with those of the putative parents, wild species Secale montamim and cultivated rye S. cereale. All weedy populations exhibited high levels of genetic variation as determined by isozyme analysis. On average, 44% of the isozyme loci were polymorphic, total genetic diversity was 0.30; and number of alleles per locus was 1.65. High genetic identities, averaging 0.994 ± 0.005 between populations, indicated that little genetic differentiation has occurred among these weedy populations since the initial colonization. Lack of population differentiation could be attributed to a wind-pollinated, self-incompatible breeding system resulting in extensive gene flow among weedy populations, and between weedy populations and local cultivars of rye. Multilocus outcrossing rates of weedy populations ranged from 0.86 to 0.97. The estimated levels of gene flow using the private-alleles method were high among weedy populations, and between cv Merced and weedy populations, with estimated Nm values of 14.50 and 8.21, respectively. The colonizing success of weedy rye is discussed and a strategy for its conservation recommended.     

Bauhinia Kunitz-type proteinase inhibitors: structural characteristics and biological properties

Abstract Plant proteinase inhibitors are involved in the regulation of the activity of many proteinases and, in consequence, in biological processes driven by proteolysis. In this review, we summarize recent results on the activity of native Bauhinia inhibitors and synthetic derivatives. Structural and functional characteristics and the potential therapeutic use of these inhibitors are also discussed.     

The spatial structure and hierarchy of the ecological groups in the skin microbiocenosis of the breasts

In 120 nulligravidae, 175 pregnant women and 280 puerperants the skin microbiocenosis of mammary glands was studied. Its horizontal structure, the types of the distribution of different ecological groups over the surface of the biotope and their hierarchy, as well as the diversity of species at different anatomical areas, were described. The study showed that the representatives of resident flora were characterized by group distribution, while for transitory flora variations from occasional distribution in nulligravidae to group distribution in nursing mothers were noted. The most pronounced changes in hierarchy were observed in puerperants. In nursing mothers a significant increase in the diversity of species at different anatomical areas were also disclosed.     

Population ecology of a colonizing species: The pelagic tunicate Thalia democratica

Summary The marine pelagic tunicate Thalia democratica has one of the fastest individual growth rates and shortest generation times of any multicellular animal. Measurements of growth in the laboratory and at sea show that this salp maintains a growth rate of over ten percent in length per hour for much of its life cycle. This salp develops through bot generations in a minimum of two days. This generation time increases to over two weeks under conditions of poorer food or lower temperature. Maternal nutrition and viviparity are among the many specialized adaptations which allow this animal to achieve such rapid growth.     

Ultrastructural and genetic characteristics of endolithic cyanobacterial biofilms colonizing Antarctic granite rocks

The precise identification of the cyanobacteria that comprise an endolithic biofilm is hindered by difficulties in culturing the organisms found in these biofilms and a lack of previous molecular and ultrastructural data. This study characterizes, both at the ultrastructural and molecular level, two different cyanobacterial biofilms found in fissures of granite from continental Antarctica. Electron microscopy revealed structural differences between the two biofilms. One was only loosely adhered to the substrate, while the other biofilm showed a closer association between cells and rock minerals and was tightly attached to the substrate. Cells from both biofilms where ultrastructurally distinct, displaying, for instance, clear differences in their sheaths. The amounts of EPS and their organization associated with the cyanobacteria may determine the differences in adhesion and effects on the lithic substrate observed in the biofilms. By sequencing part of the 16S rRNA gene, the two cyanobacteria were also genetically characterized. The gene sequence of the cells comprising the biofilm that was tightly attached to the lithic substrate showed most homology with that of an endolithic cyanobacterium from Switzerland (AY153458), and the cyanobacterial type loosely adhered to the rock, clustered with Acaryochloris marina, the only organism unequivocally known to contain chlorophyll d. This study reveals the presence of at least two different types of endolithic biofilm, dominated each by a single type of cyanobacterium, able to withstand the harsh conditions of the Antarctic climate.     

Relation of the epidemiological characteristics of dysentery to the biological properties of the causative agents

The main forms of the epidemic manifestation of dysentery induced by different causative agents in 1975-1980 were revealed. During these years the cases of dysentery induced by Shigella sonnei, biovar II, were found to prevail (82.0-90.1%) both at the periods between epidemics and at the periods of the seasonal rise of morbidity. The experimental infection of white mice by intraperitoneal inoculation revealed no relationship between the seasonal rise of morbidity in dysentery and the virulence of its causative agents.