Multiparasite communities in animals and humans: frequency, structure and pathogenic significance

A separate analysis of ulnar and radial finger ridge-counts, obtained from 115 Aymara Indians (55 males and 60 females) of northern Chile, was performed. From these variables, directional asymmetry, fluctuating asymmetry, indices of bilateral asymmetry (square root of A2), and intraindividual diversity (s/square root of 5) were calculated for each sex. The results show that most bimanual differences for the ridge-counts are not statistically significant in the Aymara, except for radial counts in female first and second fingers (right hand means are larger), while most ulnar-radial differences are highly significant in both sexes (radial values exceed ulnar ones). Most sex differences do not reach statistical significance, although males have more ridge-counts, lower directional asymmetry, somewhat lower fluctuating asymmetry, and lower indices of asymmetry and diversity than females. As fluctuating asymmetry is not larger in males, the dermatoglyphic findings do not indicate support for the hypothesis that males are less canalized than females. In accordance with the findings of other authors, interpopulation comparisons in the indices of asymmetry and diversity show ethnic differences. Both indices tend to be low in samples of African ancestry, high in samples of European origin, and intermediate in the Aymara, while Indian groups are characterized by high asymmetry and low diversity values. Moreover, the data reveal a geographical trend in that asymmetry and diversity values tend to decrease from the northern to the southern hemisphere in populations of Europe, the Middle East, and Africa, thus indicating greater ridge-count variability and heterogeneity among fingers in northern populations. It is assumed that this gradient primarily reflects different degrees of miscegenation and heterozygosity.     

Presence of various pathogenic microorganisms in fresh vegetables in Costa Rica

The treatment of large, asymptomatic, neonatal ovarian cysts is controversial. Some authors recommend surgical intervention if the cyst diameter is greater than 5 cm. We report a case of an antenatally diagnosed ovarian cyst with a diameter of 6.6 cm. It involuted spontaneously within 8 months after birth without complications. We propose a conservative management of large, uncomplicated neonatal ovarian cysts. Close observation with serial ultrasound examinations may help avoid unnecessary operations.     

Antimicrobial activity of newly synthesized isothiocyanate derivatives against pathogenic plant microorganisms

Fifteen reaction products of isothiocyanates with cysteine, seven reaction products of isothiocyanates with 2,3-dimercapto-1-propanol, and four reaction products of isothiocyanates with sulfanilamide were synthesized. Their antimicrobial activity against pathogenic plant microorganisms was investigated.     

The characteristics of new species of pathogenic microorganisms in the genus Francisella

The comparative study of newly discovered pathogenic bacteria of the genus Francisella was carried out with the use of a complex of microbiological and serological methods. While having great similarity to the causative agent of tularemia, F. novicida, F. novicida-like bacteria and F. philomiragia had lesser growth requirements, some specific morphological and structural features, were capable of fermenting sucrose and exhibited low pathogenicity to experimental animals. The strains under study proved to be virulent with regard to golden hamsters, who were for this reason proposed as an adequate model for the isolation of these bacteria from environmental objects and pathological material obtained from patients. The use of immunoblotting made it possible to find out that all Francisella species had protein antigens, similar to their electrophoretic mobility and serological activity.     

Multilocus sequence typing: a portable approach to the identification of clones within populations of pathogenic microorganisms

Traditional and molecular typing schemes for the characterization of pathogenic microorganisms are poorly portable because they index variation that is difficult to compare among laboratories. To overcome these problems, we propose multilocus sequence typing (MLST), which exploits the unambiguous nature and electronic portability of nucleotide sequence data for the characterization of microorganisms. To evaluate MLST, we determined the sequences of approximately 470-bp fragments from 11 housekeeping genes in a reference set of 107 isolates of Neisseria meningitidis from invasive disease and healthy carriers. For each locus, alleles were assigned arbitrary numbers and dendrograms were constructed from the pairwise differences in multilocus allelic profiles by cluster analysis. The strain associations obtained were consistent with clonal groupings previously determined by multilocus enzyme electrophoresis. A subset of six gene fragments was chosen that retained the resolution and congruence achieved by using all 11 loci. Most isolates from hyper-virulent lineages of serogroups A, B, and C meningococci were identical for all loci or differed from the majority type at only a single locus. MLST using six loci therefore reliably identified the major meningococcal lineages associated with invasive disease. MLST can be applied to almost all bacterial species and other haploid organisms, including those that are difficult to cultivate. The overwhelming advantage of MLST over other molecular typing methods is that sequence data are truly portable between laboratories, permitting one expanding global database per species to be placed on a World-Wide Web site, thus enabling exchange of molecular typing data for global epidemiology via the Internet.     

The gas trophicity of pathogenic bacteria]

Yersinia pseudotuberculosis and Listeria have been shown to be capable of assimilating carbon dioxide from the air and using its carbon for the synthesis of biopolymers of the bacterial cell. These microorganisms, the causative agents of saprozoonotic infections, have also been found to be capable of assimilating molecular nitrogen from the air in small amounts. The data on the influence of the growth conditions of the cultures (hydrogen concentration, the presence of carbon dioxide and oxygen, temperature) on the activity of acetylene reduction by microbial cells. At low temperature molecular nitrogen is fixed by Listeria twice as actively as by Y.pseudotuberculosis. Not all bacterial strains under study have been found to be capable of acetylene reduction. The presence of fixed nitrogen in the medium suppresses the process of the reduction of acetylene into ethylene.     

Pharmacokinetics of rifampicin in experimental animals]

Rifampicin is rapidly absorbed when administered orally. Its high levels were detected during 1 to 3 hours after administration. The antibiotic was preserved in the blood serum in therapeutic concentrations for at least 24 hours depending on the dose used. When used repeatedly, it did not cumulate. Rifampicin easily penetrated into the organs and tissues of the animals, the highest concentrations being observed in the liver and kidneys. The antibiotic was mainly excreted with the bile. The drug pharmacokinetics depended on the animal species.     

Sensitivity to ethanol across development in rats: comparison to [3H]zolpidem binding

Previous research has suggested that rats tested at 28 to 30 days of age show a marked subsensitivity to the sedative effects of ethanol. In the present study, rats of different ages were tested for aerial righting following acute ethanol (3 g/kg) treatment. These results were compared with the effects of the atypical benzodiazepine zolpidem (3 and 5 mg/kg) and pentobarbital (10 and 15 mg/kg). Animals tested at 25, 28, or 35 days of age were significantly less impaired by ethanol than preweanling rats (age 20 days) or older rats (age 65 to 75 days), whereas animals tested at 25 or 28 days of age were less impaired by the higher dose of zolpidem. With pentobarbital, the most distinct age-related trend was greater impairment in 20-day-old rats. Because ethanol may be active at the same type I GABA(A) receptor site selectively labeled by [3H]zolpidem, levels of [3H]zolpidem binding were determined for rats of different ages. Although some brain regions showed progressive increases in binding of [3H]zolpidem across development, other regions demonstrated increased binding from day 12 or 17 to day 20, then a plateau of binding levels across days 20, 25, and 28, with further increases occurring by day 36 or day 60. This pattern was observed in the cingulate cortex, medial septal nucleus, globus pallidus, inferior colliculus, red nucleus, and cerebellum. Overall, the results indicate that the period of subsensitivity to the sedative effects of ethanol is coincident with a change in the developmental pattern of GABA(A) receptor sites targeted by [3H]zolpidem.     

Possible pathogenic role of IL-16 on SLE: with reference to HIV-1 infection]

PURPOSE: To evaluate percutaneous embolotherapy in the treatment of lower gastrointestinal hemorrhage. MATERIALS AND METHODS: Twenty-one patients who underwent attempted percutaneous embolization for acute lower gastrointestinal bleeding between 1982 and 1997 were retrospectively studied. Hemorrhagic sites included jejunum (n = 4), ileum (n = 4), cecum (n = 4), and the remaining colon (n = 9). RESULTS: Embolization was not technically possible in four patients (19%). Hemostasis was achieved in 15 patients (71%) with prolonged hemostasis in 10 (48%). All embolizations distal to the cecum resulted in prolonged hemostasis. Three of four patients with jejunal bleeding had recurrent bleeding after apparent successful embolization. Only one of four cecal embolizations achieved prolonged cessation of bleeding. No ischemic complications were identified. CONCLUSION: Based on these data, it would appear that the risk of bowel ischemia/infarction in the lower gastrointestinal tract may not be as high as has been suggested. Two regions (cecum and proximal jejunum) were associated with poor results, suggesting these areas may not be as responsive to embolotherapy as other sites in the lower gastrointestinal tract.     

Effect of some preservatives on pregnancy and fetal development in experimental animals

70 rats in 7 groups of 10 rats each were studied to determine the effects of an oral administration of 3.3-dibromo-5.5-dichloro-2.2-diphenyl-methane during the period of organogenesis (the 6th-15th day of pregnancy). 5 groups received a dose of 1/1000, 1/500, 1/250, 1/100, and 1/50 of the preparation (LD50) at 1 ml/100/gm of weight. 1 control group received olive oil in a dose of 1 ml/100 gm of weight and the other was given thalidomide at 1/500 LD50. The animals were killed on the 20th day of pregnancy and the fetuses given gross inspections regarding the number of living and dead, the weight of the fetus and of the placenta, the length of the fetus and its tail, and the sex. A statistical analysis using the student t test with a probability of 5% was performed on these data. Autopsies and macroscopic investigations of the liver and kidneys were performed. The development of occipital and interparietal bones, ossification centers in the sternum, and the number of ribs were also assessed. This preparation did not exert any inhibiting influence on fetal development or cause an increase in fetal mortality.     

The prevalence of cryptosporidia among agricultural animals in Azerbaijan]

In the paper are presented the data on revealement of cryptosporidian oocysts (Apicomplexa, Sporozoa) in feces of cattle, swine and sheep of different ages and results of the experimental infection of laboratory animals (rats, mice, rabbits, coypus) with the oocysts detected as well. The latters were attributed to Cryptosporidium parvum species. The analysis of the size characteristic in the isolates of naturally and artificially infected hosts has shown that the oocysts dimensions might vary both in different host species and in different individuals of one host species.     

Sensitivity of yeasts to lithium

A wide range of tolerance to Li+ has been found among 12 different yeasts. Concentrations that do not allow long-term growth of an actively growing culture within 2-5 hr. At the same concentrations protein and RNA synthesis are inhibited with little or no lag period (less than 50 min) but respiration is not affected at these concentrations. Lower concentrations that do not inhibit growth, may impair sporulation. For given extracellular conditions, intracellular Li+ concentrations are lower in the more tolerant yeast strains.     

Microbiological study of some microorganisms implicated in sexually transmitted diseases among the female prison population

BACKGROUND: Sexually transmitted diseases (STD) are of over greater interest, particularly since the appearance of the human immunodeficiency virus ( HIV) in the last decade. Asymptomatic or oligosymptomatic infections are very frequent, overall in women. The aim of this study was to know the prevalence of certain STD producing microorganisms in a female penitentiary population, the clinical characteristics and evaluate the risk factors which may be found in this population. METHODS: One hundred thirty-three female prisoners attended in the Gynecology Ward of the Female Penitentiary of Carabanchel of Madrid, Spain, were studied over 13 months (from 30 April 1993 to 30 May, 1994). Vaginal and endocervical samples were taken in each case for microbiologic study by the usual methods. Demographic and clinical data were collected as were possible risk factors for acquiring STD (age of first sexual relations, sexual habits, intravenous drug addiction.     

The effect of taurine on the carbohydrate metabolism of diabetic animals]

A study was made of a new antidiabetic preparation--taurin in various methods of its administration to rats and rabbits with alloxan and ditisone model of diabetes. A short-term restoration of carbohydrate metabolism was seen after intraperitoneal and intravenous injection in a dose of 200 mg/kg. Oral use of aqueous taurin solution in the same dose failed to produce the desirable result. Microcapsulated taurin with acetylcellulose in the capacity of a filler given per os in a dose of 300 mg/kg restored to the normal glycogen content in the liver and leukocytes, blood and urine sugar level, and the insulin-like activity of blood plasma. Taurin (in a concentration of 3 mg/ml) possessed an insulinogenic action in experiments on fragments of the pancreas isolated from diabetia animals.     

Biodegradation of chlorpyrifos by either single or combined cultures of some soilborne plant pathogenic fungi

Biodegradation of chlorpyrifos was studied in liquid culture media amended with either single or combined eight different plant pathogenic fungi isolated from the continuous cropping wheat fields. The average recovery of chlorpyrifos from the liquid media was found to be 86.1%. The detection limit of chlorpyrifos by the analytical method used was 19 ppb. Data showed that the growth of mixed fungi at concentrations up to 200 ppm of chlorpyrifos was higher than in the control treatment. Chlorpyrifos concentrations declined in the medium of combined fungi more than it did in the medium of any single fungus with increase in the incubation period. The amount of chlorpyrifos recovered was 79.8 ppm (39.9%) in the combined fungal cultures after 21 days. However, those recovered from the media of Fusarium graminearum, F. oxysporum, Rhizoctonia solani, Cladosporium cladosporiodes, Cephalosporium sp., Trichoderma viridi, Alternaria alternata, and Cladorrhinum brunnescens, ranged from 48.0 to 74.8%. The half-life value (T1/2) for chlorpyrifos was 15.8 day in the medium amended with mixed fungi. However, for the single cultures it ranged from 19.3 to 33.0 day.