In the course of time, the laparoscopic technique has been increasingly introduced also for the surgical treatment of acute cholecystitis. The analysis of our data does not show any definitive contraindications to the laparoscopic procedure. However, the duration of surgery and the rate of conversion are significantly higher for acute cholecystitis. Morbidity is also higher, but without statistical significance. Presently we can successfully treat laparoscopically 96.8% of our own patients with acute cholecystitis.
Twenty-six Rhizobium galegae strains, representing the center of origin of the host plants Galega orientalis and G. officinalis as well as other geographic regions, were used in a polyphasic analysis of the relationships of R. galegae strains. Phage typing, lipopolysaccharide (LPS) profiling, pulsed field gel electrophoresis (PFGE) profiling and rep-PCR (use of repetitive sequences as PCR primers for genomic fingerprinting) with REP and ERIC primers investigated nonsymbiotic properties, whereas plasmid profiling and hybridisation with a nif gene probe, and with nodB, nodD, nod box and an IS sequence from the symbiotic region as probes, were used to reveal the relationships of symbiotic genes. The results were used in pairwise calculations of distances between the strains, and the distances were visualised as a dendrogram. Indexes of association were compared for all tests pooled, and for chromosomal tests and symbiotic markers separately, to display the input of the different categories of tests on the grouping of the strains. Our study shows that symbiosis related genetic traits in R. galegae divide strains belonging to the species into two groups, which correspond to strains forming an effective symbioses with G. orientalis and G. officinalis respectively. We therefore propose that Rhizobium galegae strains forming an effective symbiosis with Galega orientalis are called R. galegae bv. orientalis and strains forming an effective symbiosis with Galega officinalis are called R. galegae bv. officinalis.
Previous studies have demonstrated that cellular fatty acid analysis is a useful tool for identifying unknown strains of rhizobia and establishing taxonomic relationships between the species. In this study, the fatty acid profiles of over 600 strains belonging to the genera Agrobacterium, Bradyrhizobium. Mesorhizobium, Rhizobium and Sinorhizobium were evaluated using the gas-chromatography-based Sherlock Microbial Identification System (MIS). Data collected with the MIS showed that the three phylogenetically defined biovars of the genus Agrobacterium formed discrete clusters, whilst species belonging to the genus Mesorhizobium formed three subclusters which were easily distinguished. These three subclusters contained Mesorhizobium ciceri and Mesorhizobium mediterraneum, Mesorhizobium tianshanense fatty acid group I and Mesorhizobium plurifarium, and Mesorhizobium huakuii and Mesorhizobium loti. The genus Sinorhizobium was composed of an individual position for Sinorhizobium meliloti and a large cluster comprising Sinorhizobium fredii, Sinorhizobium saheli, Sinorhizobium terangae. Sinorhizobium kostiense and Sinorhizobium arboris. S. meliloti contained significantly higher levels of the fatty acid 19:0 cycle omega 8cis and clustered with Rhizobium sp. (Hedysarum coronarium). However, discrimination between the species of genera Sinorhizobium and Rhizobium was a function of the concentration of 16:0 3-OH. The genus Rhizobium contained a single duster containing Rhizobium sp. (Hedysarum coronarium). Rhizobium gallicum, Rhizobium leguminosarum and Rhizobium etli, along with individual positions for Rhizobium giardinii, Rhizobium tropici, Rhizobium galegae and Rhizobium hainanense. R. tropici and R. hainanense exhibited similarity to Agrobacterium biovar 2, whilst R. galegae was similar to Agrobacterium biovar 1. R. giardinii appeared unique, with comparatively little similarity to the other species. Analysis of the genus Bradyrhizobium revealed large differences from the other genera studied. Two subgroups of Bradyrhizobium elkanii were detected and easily distinguished from Bradyrhizobium japonicum. Bradyrhizobium liaoningense and Bradyrhizobium sp. (Arachis hypogaea), a group isolated from Chinese peanut plants, showed similarities to B. japonicum, whilst a subgroup of M. tianshanense appeared identical to Bradyrhizobium sp. (Arachis hypogaea).
The role of laparoscopic surgery in case of Mirizzi syndrome is not well defined, some authors regard it as a contraindication. The analysis of our patients (n = 3,700) showed an incidence of 0.43% (n = 16). Modifying McSherry's classification we saw in 31% of patients type I, in 63% type II. and in 6% type III. Conversion was needed in 4 patients (25%). Because of unknown common bile duct stones one patient was reoperated. We did not see other causes of morbidity. Laparoscopic management of Mirizzi syndrome is possible and successful in most of our cases, but an experienced surgeon is needed. In case of unclear anatomy within Calot's triangle. conversion is recommended.
SDS-PAGE of total bacterial proteins was applied to the classification of 25 Sudanese and five Kenyan strains isolated from the root nodules of Acacia senegal and Prosopis chilensis. Twenty strains were also studied by multilocus enzyme electrophoresis (MLEE) and the whole 16S rRNA gene was sequenced from two strains representing the two major clusters. These results, together with the previously reported numerical taxonomy analysis, pulsed-field gel electrophoresis studies, DNA-DNA dot-blot hybridization, genomic fingerprinting using repetitive sequence-based PCR, DNA base composition analysis, DNA-DNA reassociation analysis, partial sequencing of the 16S rRNA gene and RFLP analysis of the amplified 16S rRNA gene, showed that all 30 strains belong to the genus Sinorhizobium. Two of the strains grouped with Sinorhizobium saheli and seven with Sinorhizobium terangae, while the rest did not cluster with any of the established species. The majority of the strains formed two phenotypically and genotypically distinct groups and we therefore propose that these strains should be classified as two new species, Sinorhizobium arboris sp. nov. and Sinorhizobium kostiense sp. nov.
Bacterial strains were isolated from root nodules of various legumes, mainly trees, from different places in Africa. Polyphasic taxonomy, including numerical analysis of comparative whole-cell protein patterns obtained by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), 16S rRNA gene sequencing, auxanographic tests (API 50), and DNA:DNA hybridizations indicated that these strains belonged to Agrobacterium biovar 1. These strains were not capable of inducing any nodule or tumor formation on plants. No PCR amplification was observed using nif H primers, suggesting that they do not carry symbiotic genes. Biological implications of the presence of Agrobacterium in nodules are discussed.
Fifty-one fast growing rhizobial strains isolated from root nodules of Acacia senegal and Prosopis chilensis in Sudan and Kenya were divided into DNA homology groups using non-radioactive DNA-DNA dot-blot hybridisation. Rhizobium leguminosarum, R. galegae, R. tropici, Mesorhizobium loti, Sinorhizobium fredii, S. meliloti used in numerical taxonomy were included in the hybridisation experiments as reference strains and, at a later stage S. saheli and S. terangae. Scores given to the intensities of dots detected in the hybridisation experiments were used in principal component analysis, which clustered the majority of the tree rhizobia in two separate DNA-homology groups. The 51 strains were also analysed by genomic fingerprinting using the repetitive sequence-based polymerase chain reaction (rep-PCR) method with REP, ERIC, BOX and GTG5 primers. The resulting genomic fingerprints were compared with strains representing 15 rhizobial species. The relationship of 17 Sudanese strains to established sinorhizobial species was examined using the optical renaturation rates method and the G+C content of nine strains was determined. Results from dot-blot hybridisation and rep-PCR experiments were found to be in close agreement with each other and with the results obtained from spectrophotometric reassociation analysis. We suggest that rep-PCR fingerprinting can be used as a first and dot-blot hy bridisation as a second rapid and dependable genomic screening method to classify new rhizobial isolates of unknown taxonomic status and to choose the representative strains for the more laborious DNA-DNA reassociation experiments.
Twenty-two rhizobial strains isolated from the root nodules of two Chinese peanut cultivars (Arachis hypogaea L. Tianfu no. 3 and a local cultivar) growing at four different sites in the Sichuan province, Southwest China, were characterized by growth rate, rep-PCR, PCR-RFLP of 16S rDNA, partial sequencing of ribosomal genes, and fatty acid — methyl ester analysis (FAME), and compared with strains representing Bradyrhizobium japanicum, B. elkanii and other unclassified Bradyrhizobium sp. All peanut isolates from Sichuan were bradyrhizobia. Dendrograms constructed using the rep-PCR fingerprints grouped the strains mainly according to their geographic and cultivar origin. Based on PCR-RFLP and partial sequence analysis of 16S rDNA it appears that peanut bradyrhizobial strains from Sichuan are similar to peanut strains from Africa and Israel, and closely related to B. japonicum. In contrast, analysis of FAME data using two-dimensional principal component analysis indicated that Bradyrhizobium sp. (Arachis) were similar to, but slightly different from other bradyrhizobia. The presence and level of fatty acid 16:1 w5c was the distinguishing feature. The results of PCR-RFLP of the 16S rRNA gene, the partial sequence analysis of 16S rDNA, and FAME were in good agreement.
The shape of the short light pulses emitted from a single air bubble trapped in a resonant sound field in degassed water has been measured directly for the first time with a streak camera. At low driving pressures the pulse shape is nearly Gaussian with a slightly slower decay. With increasing driving pressure the fall time and thereby the width of the pulse increases, while the rise time remains almost constant.
PCR-RFLP with nine restriction enzymes was applied to the 16S and 23S rRNA genes of 42 rhizobial and agrobacterial strains to determine the phylogenetic position of Rhizobium galegae and increase the understanding of the evolution of ribosomal operons. The strains were selected based on previous phylogenetic studies. PCR primers were designed so that they amplified a 2.3 kb fragment of the 23S rRNA gene (excluding the B8 loop). Universal primers rD1 and fD1 were used to amplify the full-length 16S rRNA. The RFLP analysis resulted in 27 and 32 different restriction patterns for 16S and 23S, respectively. The RFLP patterns were transformed to genetic distances and dendrograms were constructed from the data using the unweighted pair group method with averages. The shapes of the dendrograms derived from the analysis of the 16S and 23S rRNA genes correlated well, with only a few strains having different positions. The 23S tree generally had deeper branching than the 16S tree, allowing better discrimination between species and strains. The combined data from the two analyses described 36 genotypes. The eight R. galegae strains formed a homogeneous cluster in all dendrograms. The RFLP analysis was confirmed by partial sequence analysis of the 16S rRNA gene (the first 800 bp), which correlated well with full-length 16S rRNA sequence analysis. The 16S data placed R. galegae near the genus Agrobacterium with Agrobacterium vitis as its nearest neighbour, whereas in the 23S and the combined dendrograms it showed closer affinity to the genus Rhizobium.