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The activity of minocycline, doxycycline, tetracycline, erythromycin, mepartricin and lincomycin against 35 freshly isolated Ureaplasma urealyticum strains was tested. Doxycycline was the most active. Twelve strains were resistant to minocycline and four of these were sensitive to erythromycin. Mepartricin showed no activity against the organisms at a concentration of 10 µg/ml. The susceptibility of 30 low-laboratory-passage Chlamydia trachomatis strains against tetracycline and erythromycin was tested. A variable degree of sensitivity to tetracycline and erythromycin was found, the median MIC values being 0.13 µg/ml and 0.025 µg/ml respectively. No resistant Chlamydia trachomatis strain was found. [ABSTRACT FROM AUTHOR]

In this work, we report the functionalization of flat Si(100) surfaces with a calix[8]arene derivative through a thermal hydrosilylation process, followed by docking with [60]fullerene. Chemical grafting of calix[8]arene on silicon substrates was evaluated by X-ray photoelectron spectroscopy, whereas host-guest immobilization of fullerene was demonstrated by atomic force microscopy and sessile drop water contact angle measurements. Surface topographical variations, modelled on the basis of calix[8]arene and [60]fullerene geometrical parameters, are consistent with the observed morphological features relative to surface functionalization and to non-covalent immobilization of [60]fullerene.

This paper reports a rapid electron spin resonance method to assess the dynamical properties of spin-labeled alkyl carboxylate layers, covalently linked onto a porous silicon substrate. IR and X-ray photoelectron spectroscopy analyses complemented the ESR study by proving the successful grafting of the organic radical and coverage of the surface.

A novel [70]fulleropyrrolidine functionalized with a nitroxide radical has been synthesized. After pulsed photoexcitation, time-resolved electron paramagnetic resonance (EPR) spectra have been recorded in liquid solution at standard X-band (9.5 GHz) and W-band (95 GHz) microwave frequencies. The spectra exhibit strongly electron spin polarized ground and excited states, the latter being arising from the spin coupling of the nitroxide's electron spin with the fullerene's excited triplet state. The EPR parameters such as g-values and hyperfine coupling constants have been discussed in terms of the spin Hamiltonian for excited doublet, triplet and quartet states. On the basis of the strength of the exchange interaction between the fullerene triplet and the radical group, two, out of a possible four [70]fulleropyrrolidine isomeric monoadducts, have been characterized.

This report describes two cases of ureteral stricture in renal graft recipients related to cytomegalovirus (CMV) and human polyoma BK virus (BKV) ureteritis with the same onset characterized by acute graft failure with no clinical signs of systemic viral infections. The histological analysis did not show other causes of graft impairment (i.e. drug toxicity and acute rejection). Ultrasound scan (US) revealed absent or mild hydronephrosis. The diuretic-MAG3 renal scan showed a urinary flow obstruction. The viral genomes were isolated from urine, peripheral blood and graft or ureteral tissues samples. A percutaneous nephrostomy confirmed the stricture, but it restored urine flow only in the graft affected by CMV ureteritis, the association with a specific antiviral therapy probably produced a stable restoration of graft function. In BKV ureteritis,the graft prognosis was poor; graft loss could be due to the progress of BKV nephropathy. A correct differential diagnosis of the etiologic agent responsible for the ureteritis is mandatory, because treatment and outcome of the infection are different.

The use of PCR assays as a fast and reliable method is constantly improving and easing microbiological diagnosis. We used a polymerase chain reaction (PCR) assay designed to detect Mycoplasma genitalium and Chlamydia trachomatis in urethral swab samples of 56 males with urethritis and 44 asymptomatic patients as a control group. The PCR assay provides an amplification of target sequence within MgPa (M. genitalium protein attachment) gene. Results indicated that M. genitalium was present in 6 (10.7%) patients with urethritis and none in the control group. Eleven of 56 (17.8%) patients were positive for Chlamydia trachomatis when tested by an outer membrane protein primer-based PCR. The amplified DNA fragments were homogeneous as shown by restriction enzyme analysis and found to be consistent with the published sequences. The PCR assay employed was as reliable as the cultural method in detecting C. trachomatis in the urethral swabs of patients with urethritis (100% of sensitivity when compared with the cultural method) and it has been revealed as an essential method for detection of M. genitalium.

Bacillus of Calmette-Guerin (BCG) was found to be effective in the therapy of superficial bladder cancer, although the mechanisms by which this occurs have not yet been clarified. One hypothesis is related to the ability of monocytes/macrophages (MN/M phi) to release tumor necrosis factor-alpha (TNF-alpha), a monokine with cytotoxic and cytostatic effects against certain tumor cell lines. The present study demonstrates that BCG and C. albicans are both very efficient inducers of TNF-alpha, while they inhibit uridine uptake and incorporation into human MN/M phi RNA. However, unlike C. albicans, BCG is cytotoxic for MN/M phi, as determined by release of labelled leucine from target cells.

A marked reduction of [3H]-uridine uptake was observed when mouse peritoneal macrophages (pM phi) were exposed to heat-killed Candida albicans or Saccharomyces cerevisiae. By contrast, an increased nucleoside uptake was promoted by yeast products such as zymosan, laminarin, or yeast cell-wall extracts, which are mainly composed of beta-glucans and alpha-mannans. In a search for the active fungal component(s), the uptake process was shown to be differently affected by monosaccharides and polysaccharides. These findings support the view that a specific recognition of a pM phi membrane receptor is mediating the effect of the various substances.

Two mycoplasmas have been observed with increasing frequency in patients with genitourinary disorders: Mycoplasma hominis and Ureaplasma urealyticum. Mycoplasma cells of both these species have been demonstrated to be capable of attaching to human spermatozoa of infertile patients. The mechanisms for the association of infertility and mycoplasma infection have not been established. The main objective of this article was to explain the significance of some morphologic features of spermatozoa of patients with unexplained infertility using light and electron microscopy. These studies and quantitative analysis of ureaplasmas in the semen indicate that at least two patterns can be seen. Frequently, sphere-shaped particles adhering mainly to the midpiece of spermatozoa were detected. In a second, more complex pattern ureaplasmas were seen inside a swollen zone on the midpiece, which suggests that the infection does not occur in the urethra, but at another unknown site. Furthermore, the sphere-shaped particles cannot be associated with ureaplasmas because their titers in the semen of infertile patients were much lower than those expected.

Colonies of Mycoplasma hominis, Acholeplasma laidlawii (three strains) and Ureaplasma urealyticum were examined by light and electron microscopy and their characteristic morphology, ultrastructure and morphogenesis are described. Mycoplasma hominis and A. laidlawii, PG8 and oral strains, developed typical 'fried-egg' colonies which were remarkably heterogeneous in size. The colonies of A. laidlawii strain NCTC 10116 were more homogeneous and grew mainly on the surface of the agar showing a fine granular appearance. Ureaplasma urealyticum produced smaller, granular colonies which grew deeply embedded in the agar and generally without much surface growth. The cellular ultrastructure in these colonies was also examined. The results indicate that several aspects of colony morphogenesis and ultrastructure varied for each of the three species examined.

An immune-enzymatic method was developed for the determination of antispermatozoal antibodies. Sera of 94 infertile patients were studied with the enzyme-linked immunosorbent assay (ELISA). Twelve patients were positive for antispermatozoal antibodies. Forty-six of these patients were studied also with the gelatin agglutination test (GAT). Eight sera were positive in the ELISA and nine in the GAT. With ELISA, immunoglobulin classes can be demonstrated; in fact, nine of our patients were positive for IgG and three for IgM. In all patients the IgA titer was less than 1:16. In addition, 61 seminal fluid specimens were studied by ELISA, and 7 were positive. The serum and seminal fluid of 12 patients were simultaneously studied. Seminal fluid was positive in only three patients, serum was positive in four, whereas serum and seminal fluid were both negative in five. This study illustrates that ELISA is apparently less sensitive than GAT; however, it is certainly more practical and an easier method for antibody research in sera and in seminal fluid.

The effects of some genital mycoplasmas on the in vitro penetration of human spermatozoa into the master egg were studied. Ureaplasma urealyticum serotypes 4, 8, and 6 showed high interfering activity: 6.3% (P less than 0.01), 12.3%, and 14.5%, respectively, against the 55.6% penetration rate of untreated sperm. Neither a cytotoxic effect of mycoplasmas on gametes nor a masking of the binding sites on the egg surface were demonstrated. In experiments carried out with U. urealyticum serotype 4, the production of diffusible relatively heat-labile factor(s) responsible for the inhibition of sperm penetration was postulated.

Various methods of detection are available for measuring antibodies specific to M. pneumoniae. We examined over 600 sera of patients with clinical diagnosis of M. pneumoniae infection using complement fixation (CF) test. 91 gave positive reaction and were therefore selected for a comparative analysis with other methods such as metabolic inhibition (MI), mycoplasmocidal (MC) and radioimmunoprecipitation (RIP) methods. MC and RIP test gave antibody titers comparatively higher than MI and CF. Comparative studies on the sensitivity of the various methods considered were also carried out on 6 paired sera collected from the same patients at 10 days intervals. The increase in antibody titers were much higher when MC and RIP tests were considered. When RIP and MC methods were compared, the first appeared more sensitive in all cases studied.

An approach to diagnostic microbiology necessitates measures which maintain the flora unchanged during the transportation of the specimens to the laboratory, preserving the viability of labile and fastidious organisms such as mycoplasma. Some of these problems have been studied in the present investigation. Five different swabs (untreated, albu, charcoal, alginate and phosphate-buffered albumin) and three transport media (Stuart, Amies and MTB) were examined using genital mycoplasma. Absorbent effect of swabs treated with albumin is lower than all the others while the antimycoplasma activity, due to the toxic substances present in the fiber of tip swab, is always lower for the charcoal swab. Concerning transport media, the most favourable results were obtained with the MTB medium. In this medium M. hominis and U. urealyticum counts decreased about 0.5 log and M. fermentans decreased 1.25 log after seven days at 4 degrees C. Furthermore, after inoculation of mycoplasma, MTB can be frozen at -20 degrees C without greatly modifying the titer. The reasons of the different performance of transport media on mycoplasma survival were discussed.

The kinetics of induction of lambda prophage with bleomycin A2-CP3, mitomycin C and a combination of these two antibiotics have been studied. Bleomycin has been found to cause a rapid induction of prophage in exponentially growing cultures of E. coli K12 (lambda), and the maximal values of including activity are obtained after treatment for 16 minutes with a concentration of 10 mug/ml. The per cent of induction, calculated from the total number of surviving cells, including the phage producing cells, better expresses the dynamics of the phenomenon. The number of inducing events in the population of exposed cells is proportional to the length of bleomycin treatment. These values are greater than those observed after treatment with mitomycin, at the same concentration. Inducing activity is enhanced by combination of the two antibiotics and this effect is not additive, but synergic. After the 16 minutes of treatment with bleomycin the burst sizes are lower than those which are obtained with mitomycin or with the combination of the two antibiotics. The results are interpreted as a consequence and a confirmation of the different mechanisms of action that distinguishes bleomycin from mitomycin.

Although clinical observations have suggested that Ureaplasma urealyticum may be associated with reproductive failure, the role of ureaplasmas in human infertility remains controversial. However, the mechanism whereby ureaplasmas can interfere with the fertilization process is not known. To study possible mechanisms, we used the human sperm-hamster egg fertilization test. Eggs were exposed to the spermatozoa preincubated with Mycoplasma hominis or U. urealyticum (serotype 1-8). U. urealyticum serotype 4 showed greater interference activity on the penetration rate (6.6%) than did the other mycoplasmas, as compared with the control (55%). Furthermore, our data suggest that the inhibition of penetration was not related to a masking of sperm membrane sites, since the mean of adsorbed spermatozoa/egg after preincubation of spermatozoa with mycoplasmas was not significantly different from that of the control. In addition, eggs preincubated with U. urealyticum serotype 4 gave a reduction of the penetration rate by untreated spermatozoa.

The in vitro antimycoplasmal activity of mepartricin was evaluated on several mycoplasma strains. The results demonstrate that this polyene antibiotic possesses a high efficacy against these microorganisms.

Many studies of the interaction between phagocytes and mycoplasmas have given controversial results. This is probably due both to the small size of the microorganisms and their ability to attach to the cell membrane, making it difficult to distinguish between adsorption and ingestion. To overcome these difficulties we took advantage of a phenomenon we noted occurring concomitantly with phase-contrast microscope-monitored phagocytosis of heat-killed C. albicans, i.e., a reduction of [3H]uridine uptake by macrophages from culture medium. This approach allowed us to measure the ability of mouse peritoneal macrophages and the macrophage-like P 388 D 1 continuous cell line to phagocytose Mycoplasma pneumoniae and Acholeplasma laidlawii. Live, UV-killed and specific antiserum-opsonized mycoplasmas were tested. A. laidlawii was ingested under all the conditions mentioned above, while live M. pneumoniae was not phagocytosed unless UV-killed. Phagocytosis of UV-killed M. pneumoniae was directly verified by transmission electron microscopy studies. Data obtained with opsonized M. pneumoniae indicated no ingestion by mouse peritoneal macrophages and incomplete phagocytosis with P388 D 1 macrophages, suggesting that different responses by different types of phagocytes can be observed. In spite of a lack of information concerning the biological meaning of the inhibition of macrophage RNA metabolism during phagocytosis, our data suggest that this phenomenon may be used to study the phagocytosis of microorganisms which are difficult to visualize.

A microbiological examination has been carried out in 116 patients with unexplained infertility and with asymptomatic bacteriospermia. Organisms more frequently isolated were Staphylococcus epidermidis (81.9%), non hemolytic streptococci (23.3%), diphtheroids (25%) and alpha-hemolytic streptococci (18.1%). None of the 103 patients were positive for C. trachomatis. Mycoplasmas were isolated in 56 (48.3%) of the 116 examined samples, U. urealyticum was present in 49 (42.2%), M. hominis in 3 (2.6%) and both species in 4 (3.5%) samples of examined fluids. Forty-one of the 56 mycoplasmas-positive patients have been treated with doxycycline therapy. The treatment improved motility and caused decrease of coiled tails in 12 cases. Conception occurred in 5 (26.3%) of the 19 treated patients whose cultures were negative for mycoplasmas. These 5 pregnancies occurred in the patients that had high titers (greater than 10(5) c.c.u./ml) of ureaplasmas and in which the antibiotic therapy was successful. No pregnancy was seen in the other 22 patients where treatment failed to eradicate mycoplasmas.

The study of [3H]-uridine uptake by mouse peritoneal macrophages showed that this is an active, temperature- and protein synthesis-dependent phenomenon, which is early altered when are exposed to a variety of stimuli. Murine recombinant interferon-gamma, a stimulus able to activate macrophage and to induce the production of tumor necrosis factor-alpha, within few hours markedly increased [3H]-uridine uptake by mouse macrophage. Other stimuli devoid of activation capacity, such as inert phagocytable latex beads, did not affect this phenomenon, which appeared to be related to macrophage activation. The increase in [3H]-uridine uptake may be an useful phenomenon in studying the early biochemical events associated with macrophage activation.