Haemolytic activity of Aeromonas species isolated in Libya

Twenty seven Aeromonas strains (5A. hydrophila, 8A. sobria and 14A. caviae) isolated from children with diarrhoea and 34 Aeromonas strains (9A. hydrophila, 7A. sobria an 18A. caviae) isolated from children without diarrhoea were tested from haemolysin production. The results obtained showed that haemolysin production using human, horse or sheep erythrocytes was significantly associated with A.hydrophila and A sobria but not with A.caviae, regardless of whether these strains were isolated from children with or without diarrhoea. Human or horse rather than sheep erythrocytes are recommended for use in the haemolysin assay.     

Phenotype markers in strains of Aeromonas isolated in Cuba from children with an acute diarrheic disease

Twenty-seven cases of Aeromonas isolated from 300 five-years children with acute diarrheal disease (EDA) were studied, with the aim for demonstrating the occurrence of some phenotypical markers associated with enteropathogenicity; among them were lysine decarboxylation, acetil methyl carbinol production, enterotoxigenicity, cytotoxicity and hemolysis. The percentage of analysed strains had two or more of the investigated markers, and 13 (48.1%) lysed the rabbit erythrocytes with titres higher than than 1:16. The presence of markers in Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae was demonstrated.     

Application of a colorimetric DNA-DNA hybridization method for identification of Aeromonas genomic species, isolated from diarrheal stools

In this report we describe a male patient with the interesting combination of a large congenital scalp defect, distal limb reduction anomalies, right spastic hemiplegia and hypoplasia of the left arteria cerebri media. Follow-up data from birth up to the age of 18 years revealed positive evolution with low to normal intelligence. The findings in the present patient, i.e. an Adams-Oliver syndrome associated with a severe neurological deficit, are best explained as resulting from interruption of the early embryonic blood supply.     

Isolation and identification of Aeromonas species from human stools

One thousand and three diarrhoeal stool samples were processed in our laboratory during the period 1996/1997 for the presence of enteric pathogens especially Aeromonas spp., which has emerged as a new agent causing diarrhoea. Ampicillin sheep blood agar was found to be the best medium for the isolation of Aeromonas spp. from stool specimens. Enteric pathogens were found in 200 (20%) stools, of which Aeromonas spp. was the second commonest pathogen isolated amounting to 21% of isolates. This study clearly indicates that Aeromonas spp. must be looked for in every diarrhoeal stool samples, specially in children below 10 years of age. Isolation and identification is cost effective and easy, if the given protocol is observed.     

Aeromonas species in fish, fish-eggs, shrimp and freshwater

Two types of widely coexpressed cell surface C1q-binding proteins (C1q-R): a 60-kDa calreticulin-homolog which binds to the collagen-like "stalk" of C1q and a 33-kDa protein with affinity for the globular "heads" of the molecule, have been described. In this report, we show that the two molecules are also secreted by Raji cells and peripheral blood lymphocytes and can be isolated in soluble form from serum-free culture supernatant by HPLC purification using a Mono-Q column. The two purified soluble proteins had immunochemical and physical characteristics similar to their membrane counterparts in that both bound to intact C1q and to their respective C1q ligands, cC1q and gC1q. In addition, N-terminal amino acid sequence analyses of the soluble cC1q-R and gC1q-R were found to be identical to the reported sequences of the respective membrane-isolated proteins. Ligand blot analyses using biotinylated membrane or soluble cC1q-R and gC1q-R showed that both bind to the denatured and nondenatured A-chain and moderately to the C-chain of C1q. Moreover, like their membrane counterparts, the soluble proteins were found to inhibit serum C1q hemolytic activity. Although cC1q-R was released when both peripheral blood lymphocytes and Raji cells were incubated in phosphate-buffered saline for 1 hr under tissue culture conditions, gC1q-R was releasable only from Raji cells, suggesting that perhaps activation or transformation leading to immortalization is required for gC1q-R release. Subcellular fractionation of Raji cells and analyses by enzyme-linked immunosorbent assay and Western blotting showed that the two molecules are present in the cytosolic fractions as well as on the membrane. The data suggest that soluble forms of both C1q-binding molecules are released from cells and that these molecules may play important roles in vivo as regulators of complement activation.     

Unusual antigenic and genetic characteristics of human respiratory syncytial viruses isolated in Cuba

The G protein of 23 strains of human respiratory syncytial virus isolated in Havana, Cuba, between October 1994 and January 1995 was analyzed at the antigenic and genetic level. All viruses reacted with 10 of 11 antibodies specific for the Long strain. Moreover, the G protein gene of the Cuban isolates had only five nucleotide differences from the sequence of the Long gene. The homogeneity of the Cuban isolates and their resemblance to an ancient strain, such as Long, are at odds with previous findings for viruses isolated in countries with a temperate climate and different socioeconomic status. The G proteins of three of four other viruses isolated in Havana 2 years later (1996) were also identical to those of the 1994-to-1995 isolates, and the fourth virus had a single extra nucleotide difference. This, again, is unusual, since no identical viruses had been isolated in different epidemics previously. The singular characteristics of the Cuban isolates reported here are discussed in terms of the epidemiological, climatic, and socioeconomic characteristics of Cuba.     

Non-tuberculous mycobacteria isolated in Cuba during the 1985-1989 period. Preliminary report

A number of 1,061 strains of nontuberculous mycobacteria referred to "Pedro Kouri" Institute of Tropical Medicine during the period of 1985-1989 were studied. Strains were from Provincial Centers of Hygiene and Epidemiology of the country. According to the results obtained, most of the strains classified are found in groups III and IV according to the criteria of Runyon (54, 76, and 36%, respectively). Species with a greater frequency belong to the complex MAI and M. fortuitum.     

Identification of Aeromonas strains of different origin to the genomic species level

Geographic parameters of migration were analyzed on the basis of data on birthplaces of individuals who contracted marriages in Moscow 1955, 1980, and 1994 to 1995. It was shown that the relationship between the migration rate and distance significantly changed in the 1990s. Investigation of ethnic composition of migrants demonstrated that an increase of migration activity of residents of Transcaucasia and North Caucasus recorded in 1990s was associated with an increase in migration to Moscow of representatives of indigenous populations of these regions rather than with repatriation of Russians. Analysis of migration with the use of the Malecot's model of isolation by distance showed that genetically effective migration accounted for 1/7, 1/3, and 1/4 of the total marital migration rate in 1995, 1980, and 1990, respectively. An increase in mean migration distance in 1995 to 1980 is explained mainly by a decrease in the proportion of short-range migration. The level of isolation by distance was extremely low and showed a trend to further decrease during the 40-year time interval. Parameters of the model indicated that at present the population of the central part of the Moscow oblast in the 80-km zone from the city center should be assigned to the Moscow population.     

Demonstration of celiac disease in Cuba

A study performed in 50 children carriers of celiac disease with ages between 8 months and 14 years of age, is presented; diagnosis was proved based on clinical picture, histological changes of jejunal mucosa, intestinal absorption tests and response to the suppression of gluten from the diet, with clinical, histological and biochemical control according to international criteria. It has been insisted on the familial study and the gluten overload test and its incidency in the black race. The development of public health has made it possible to demostrate the existence of this disease in our country.     

Automated sentinel system of infectious diseases in Cuba

We state that the creation of the Automated System of Epidemiological Surveillance should become an integral part of the Service of Hygiene and Epidemiology of the Republic of Cuba, which allows for the operative evaluation of the epidemiological situation in the country in order to take timely anti-epidemiological and prophylactic steps.     

Aeromonas popoffii sp. nov., a mesophilic bacterium isolated from drinking water production plants and reservoirs

We examined the taxonomic position of seven Aeromonas isolates, recovered from Flemish and Scottish drinking water production plants and reservoirs, which were previously recognized by numerical analysis of genomic AFLP fingerprints as members of an unknown Aeromonas taxon that most closely resembled the species Aeromonas bestiarum (DNA hybridization group [HG] 2). The new phenotypic and DNA-DNA hybridization data obtained in this study show that the A. bestiarum-like strains constitute a separate Aeromonas species, for which the name Aeromonas popoffii sp. nov. is being proposed. The new species exhibited an internal DNA relatedness ranging from 79 to 100% and was 22 to 63% related to the type or reference strains of other Aeromonas spp. The highest DNA binding values were determined with A. bestiarum (51 to 63%), followed by Aeromonas hydrophila sensu stricto (HG1; 50 to 60%) and Aeromonas salmonicida (HG3; 39 to 55%). Although fingerprints generated by ribotyping and cellular fatty acid analysis often were highly similar, minor differences between the respective fingerprints were of significance for the differentiation of A. popoffii from its closest taxonomic neighbors, HG1, HG2, and HG3. Phenotypically, all seven strains of A. popoffii were positive for acid and gas production from D-glucose and glycerol, growth in KCN broth, arginine dihydrolase, DNase, Voges-Proskauer reaction, and resistance to vibriostatic agent O/129 and ampicillin but displayed negative reactions for production of urease, tryptophan deaminase, ornithine decarboxylase, and lysine decarboxylase (LDC). None of the strains displayed strong hemolytic activity. The lack of D-sucrose fermentation and LDC production and the ability to utilize DL-lactate as the sole energy and carbon source were useful characteristics for the biochemical separation of A. popoffii from A. bestiarum. Other Aeromonas spp. could be differentiated phenotypically from the new species by at least two features. The chromosomal G+C content of A. popoffii ranges from 57.7 to 59.6 mol%. Strain LMG 17541 is proposed as the type strain.     

A new Borrelia species isolated from patients with relapsing fever in Spain

BACKGROUND: Lyme disease and tick-borne relapsing fever are worldwide systemic borrelioses caused by several Borrelia species transmitted by hard ticks (family Ixodidae) and soft ticks (family Argasidae), respectively. A previous seroepidemiological study of Lyme borreliosis showed several serologically reactive patients with clinically atypical presentations, and this discovery led to the hypothesis that some of the cases of Lyme borreliosis had been caused by another borrelia organism. METHODS: Blood from patients in southern Spain who had suspected Lyme disease or relapsing-fever borreliosis was cultured before treatment began. Isolates of Borrelia spp were inoculated into several strains of mice of different ages. The 16S rRNA and flagellin in genes of Borrelia spp were sequenced by PCR and assessed by phylogenetic analyses. FINDINGS: We isolated a species of Borrelia from three patients with relapsing fever and from Ornithodorus spp ticks in southern Spain. This organism (refractory to in-vitro cultivation) caused a relapsing spirochaetaemia with multiple organ involvement in laboratory mice that recreated the human disease. Phylogenetic analysis showed that this organism is a previously unrecognised species. INTERPRETATION: We have discovered a new borrelia pathogen that is closely related to the other tick-borne agents of relapsing fever in Europe and Africa, and which causes a relapsing systemic disease with serological similarities to Lyme borreliosis.     

Clinical characterization of patients with multiple sclerosis defined in Cuba

INTRODUCTION: Since 1975 no studies have been done in Cuba defining the clinical characteristics of patients with multiple sclerosis (MS). OBJECTIVE: To describe the characteristics of a group of Cuban patients with definite clinical MS. MATERIAL AND METHODS: Fifty eight patients with definite clinical MS were studied (Poser et al) with normal motor (VCM) and sensory (VCS) conduction velocities. Tests were done on them: clinical scale (Scripps), incapacity (EDSS) and quality of life (Steps), together with various complementary tests. Each patient was classified according to the way in which the disease evolved. Also the two commonest clinical types were compared and we applied the difference test between percentages of non-paired samples with an alfa level of 0.05. RESULTS: Onset of the illness in most cases was before the age of 40 (86.1%), 75.9% were women and 82.8% were white. In 15.3% there was a family history of MS. In 25.9% there were psychiatric disorders and trigger factors (43.1%. The most frequent initial symptoms were pyramidal (48.3%) sensorial (41.4%) and cerebellar (39.7%). Scripps scale scores were < 80 in 60.2%, in EDSS < 5 (61.9%) and in the Clinical Steps < 3 in 65.4%). Motor potentials (81.9%) somatosensory potential (PESS) (72.3%) and magnetic resonance imaging (MR) (76.4%) were the most abnormal results. Exacerbation-remission (ER) was the most frequent type of evolution (53.4%) generally affecting patients aged under 40 years old (p = 0.02), EDSS < 5 (64.4%), Scripps > 80 (61.2%), Steps < 3 (95.6%), pyramidal system involvement (58.5%), cerebellar (29.2%) and MRI abnormality (80%). The progressive primary form (PP) was the second most frequent (29.3%); 29.4% were under 40 years of age, had more marked changes in all functional system (100%), degree of incapacity and quality of life (100%). PESS (92.5%); the urodynamic tests 58.85%) were less positive on MRI (54.5%) as compared with the ER form. CONCLUSIONS: The differences found between the clinical forms ER and II indicate that there is greater deterioration in the PP form, probably due to age and more cerebellar and spinal cord involvement.     

Evolving concepts regarding the genus Aeromonas: an expanding Panorama of species, disease presentations, and unanswered questions

It has been almost 10 years since a major review on the association of Aeromonas with human disease has been published. During that period the number of valid species in the genus has grown to 14, with a new family (Aeromonadaceae) established to house this genus. Despite this explosion in the number of new genomospecies, only five (Aeromonas hydrophila, A. caviae, A. veronii, A. jandaei, and A. schubertii) are currently recognized as human pathogens. New syndromes attributed to this genus include hemolytic uremic syndrome, burn-associated sepsis, and a variety of respiratory tract infections, including epiglottitis. Convincing evidence suggests that some aeromonads do cause gastroenteritis, but it is presently unclear whether many of the strains isolated from feces are involved in diarrheal disease. Many questions regarding this genus remain unanswered.     

Structure of complex cell wall polysaccharides isolated from Trichoderma and Hypocrea species

The structure of fungal polysaccharides isolated from the cell wall of Trichoderma reesei, T. koningii, and Hypocrea psychrophila, have been investigated by means of chemical analyses and 1D and 2D NMR spectroscopy. The polysaccharides have an irregular structure, idealized as follows: [formula: see text] The proportions of the different side chains vary from a species to another, being n above some three times larger in H. psychrophila than in T. reesei or T. koningii.     

Serologic marker as indicator of no circulation of poliovirus in Cuba

The surveillance of the circulation of the wild poliovirus is an essential element for the eradication of poliomyelitis. The Pan-American Health Organization emphasises on the etiological study of acute flaccid paralysis in order to achieve this aim. The characteristics of our program against this entity allowed to use the presence of antibodies in a sample obtained in February from the infant population born on July during the previous year as criteria to know the circulation of wild poliovirus. In 727 infants studies in the country (5% of the total number of births during July), 99.1% showed no antibodies with a titre equal or greater than 1:10. Low titres found in 7 infants were considered as a remnant from maternal transmission. Results obtained represent a strong evidence of the fact that there is no environmental circulation of poliovirus during the period which had the greatest incidence of the disease.