Denitrification activity of phage types representative of two populations of indigenous Rhizobium meliloti

1989 ◽  
Vol 35 (7) ◽  
pp. 737-740 ◽  
Author(s):  
Y.-K. Chan ◽  
L. R. Barran ◽  
E. S. P. Bromfield
Keyword(s):  
Medicago Sativa ◽  
Rhizobium Meliloti ◽  
Previous History ◽  
Indigenous Populations ◽  
Frequency Of Occurrence ◽  
Phage Types ◽  
Denitrification Activity ◽  
History Of ◽  
Phage Sensitivity ◽  
Two Populations

Isolates of Rhizobium meliloti from indigenous populations at two sites were previously characterized according to phage sensitivity. Isolates representative of the 55 and 65 phage types comprising these two populations, respectively, were tested for denitrification activity with nitrate or nitrite as substrate. Fifty-seven of 120 isolates were capable of denitrification with activities varying considerably between phage types. Only one isolate was able to denitrify nitrite but not nitrate, indicating the presence of a truncated denitrification pathway. Each of five phage types showed variation in denitrification ability between isolates from different sites, indicating possible adaptation of indigenous R. meliloti to their respective environments. The estimated frequency of occurrence of denitrifiers in the two indigenous populations of R. meliloti (9 and 13%) differed significantly between sites with and without a previous history of Medicago sativa cultivation, respectively.Key words: Rhizobium, denitrification, populations, phage.

Does siderophore production influence the relative abundance of Rhizobium meliloti in two field populations?

1993 ◽  
Vol 39 (3) ◽  
pp. 348-351 ◽  
Author(s):  
L. R. Barran ◽  
E. S. P. Bromfield
Keyword(s):  
Soil Ph ◽  
Relative Abundance ◽  
Iron Content ◽  
Direct Relationship ◽  
Rhizobium Meliloti ◽  
Siderophore Production ◽  
Frequency Of Occurrence ◽  
Apparent Absence ◽  
Phage Types ◽  
Phage Sensitivity

Populations of indigenous Rhizobium meliloti isolated from nodules of alfalfa grown at sites A and B (soil pH, 7.0 and 6.1, respectively) were previously characterized on the basis of phage sensitivity and divided into 55 and 65 phage types. The available iron content of soil at site B was significantly higher than that at site A. Isolates representing the phage types comprising each of these populations were tested for the production of siderophores. The frequency of siderophore-producing (sid+) phage types of R. meliloti, estimated from the distribution of types in the two field populations, was significantly higher at site A (54%), where iron was less available, than at site B (18%). The distributions of frequency for sid+ and sid− phage types were similar at site A but differed (P < 0.005) at site B, where the soil was slightly acidic and contained more available iron. The apparent absence of a direct relationship between siderophore production and frequency of occurrence suggests that siderophore production may not influence the relative abundance of R. meliloti in these populations at sites differing in iron availability.Key words: siderophore, iron, Rhizobium meliloti, populations.

A cryptic plasmid of indigenous Rhizobium meliloti possesses reiterated nodC and nifE genes and undergoes DNA rearrangement

1992 ◽  
Vol 38 (6) ◽  
pp. 563-568 ◽  
Author(s):  
V. K. Rastogi ◽  
E. S. P. Bromfield ◽  
S. T. Whitwill ◽  
L. R. Barran
Keyword(s):  
Genomic Dna ◽  
Rhizobium Meliloti ◽  
Phage Type ◽  
Cryptic Plasmid ◽  
Dna Rearrangement ◽  
Homologous Sequences ◽  
Phage Types ◽  
Phage Sensitivity ◽  
Cryptic Plasmids ◽  
Free Strain

Indigenous Rhizobium meliloti were previously characterized on the basis of plasmid profiles and phage sensitivity patterns (phage types). Rhizobium meliloti 1076, which contained two cryptic plasmids, was one of four isolates comprising phage type 23. In this study, the large cryptic plasmid pVS1(size >500 b) was transferred from isolate 1076 into the plasmid-free strain of Agrobacterium tumefaciens UBAPF1. This plasmid contained nucleotide sequences homologous to genes for nodulation (nodB, nodC) and nitrogen fixation (nifH, nifD, nifK, nifE). Cosmid clones possessing the nod and nif homologous sequences, which had been selected from a genomic bank of A. tumefaciens UBAPF1 containing pVS1, complemented R. meliloti nodC and nifE mutants, respectively. These results demonstrate that the nodC and nifE homologous sequences are functionally expressed. Three of four isolates comprising phage type 23 possessed a megaplasmid band in agarose gels characteristic of R. meliloti, as well as two cryptic plasmids. The fourth isolate (No. 323) lacked the large cryptic plasmid corresponding to pVS1, but instead showed a band of lesser mobility than that of the megaplasmids. Nevertheless, its restricted genomic DNA retained the nodC and nifE hybridizing fragments characteristic of pVS1, indicating that the cryptic plasmid has undergone DNA rearrangement. Key words: Rhizobium, plasmid, reiteration, genes, rearrangement.

scholarly journals Sensitivity of Cladosporium caryigenum to Propiconazole and Fenbuconazole

Plant Disease ◽  
1997 ◽  
Vol 81 (2) ◽  
pp. 163-166 ◽  
Author(s):  
Katherine L. Reynolds ◽  
Timothy B. Brenneman ◽  
Paul F. Bertrand
Keyword(s):  
Previous History ◽  
Cross Resistance ◽  
Relative Growth ◽  
Colony Diameter ◽  
Pecan Scab ◽  
History Of ◽  
Dmi Fungicides ◽  
Cladosporium Caryigenum ◽  
Positive Correlations ◽  
Two Populations

Monoconidial isolates of the pecan scab fungus, Cladosporium caryigenum, were obtained in 1993 and 1994 from one pecan orchard each in Jeff Davis and Troup counties in Georgia, counties with no previous history of exposure to demethylation-inhibiting (DMI) fungicides. Isolates were grown on potato dextrose agar (PDA) amended with propiconazole or fenbuconazole at 0,0.0001, 0.0005, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1.0, or 5.0 µg ml-1. After 4 to 5 weeks at 25°C, the diameter of each colony was measured. Relative growth was expressed as the colony diameter for each fungicide concentration as a percentage of the diameter on unamended PDA. (ED)50 values for both fungicides in all years and locations were lognormally distributed. Mean (ED)50 values ranged from 0.19 to 0.30 µg ml-1 for fenbuconazole and 0.12 to 0.17 µg ml-1 for propiconazole. There were highly significant positive correlations between sensitivity to propiconazole and sensitivity to fenbuconazole at all locations and years, indicating significant potential for development of cross-resistance to these compounds. A discriminatory concentration of 0.2 µg ml-1 propiconazole was selected for further monitoring of DMI sensitivity. With this discriminatory concentration, a sample size of 50 isolates was estimated to be sufficient to detect a difference of 8.3% in mean relative growth between two populations.

scholarly journals Plasmids and Symbiotic Effectiveness of Representative Phage Types from Two Indigenous Populations of Rhizobium meliloti

Microbiology ◽  
1987 ◽  
Vol 133 (12) ◽  
pp. 3457-3466 ◽  
Author(s):  
E. S. P. Bromfield ◽  
N. P. Thurman ◽  
S. T. Whitwill ◽  
L. R. Barran
Keyword(s):  
Rhizobium Meliloti ◽  
Indigenous Populations ◽  
Symbiotic Effectiveness ◽  
Phage Types

scholarly journals Otoscopic and Audiologic Findings in an Ati Community in Boracay

2007 ◽  
Vol 22 (1-2) ◽  
pp. 19-21 ◽  
Author(s):  
Maria Rina T. Reyes-Quintos ◽  
Regie Lyn P. Santos ◽  
Ma. Leah C. Tantoco ◽  
Rodante A. Roldan ◽  
Kathleen R. Fellizar ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Otitis Media ◽  
Previous History ◽  
Normal Hearing ◽  
Indigenous Populations ◽  
Chronic Suppurative Otitis Media ◽  
World Health ◽  
Prevalence Rates ◽  
Suppurative Otitis Media ◽  
History Of

Background: Certain indigenous populations have been noted by the World Health Organization (WHO) to have the highest prevalence rates for chronic suppurative otitis media (CSOM), including the Australian Aborigines (28-43%), Greenlanders (2-10%) and Alaskan Eskimos (2-10%). Objectives: To determine the prevalence of common ear problems, particularly CSOM, among the indigenous Ati or Aeta community in Bolabog, Boracay, and to determine their hearing sensitivity using screening audiometry. Methods:              Study Design: Descriptive cross-sectional study.             Setting: A small Ati community in Bolabog, Boracay.             Population: A total of 63 adults and children underwent medical interview and                             otoscopy. Additionally 24 had their hearing screened by audiometry. Results: About a quarter of the population participated in the study, including 41 children (40% of all children) and 22 adults (18% of all adults). Forty-six percent of children and 23% of adults who were examined had previous history of ear discharge, while 22% of children and 45% of adults who were examined had history of hearing loss. Seventeen percent of children had history of hearing loss in the family. CSOM was found in 18 (43.90%) children and 8 (36.36%) adults. Impacted cerumen was found in 17.1% of children. Eleven female children underwent screening audiometry.  Of these, eight had normal hearing and three had abnormal findings. Thirteen adults were also tested, five of whom were male and had normal hearing bilaterally. Four of eight female adults had abnormal hearing, of which three were unilateral. Conclusions: The Ati population in Bolabog, Boracay belongs to a group with the highest prevalence rates for CSOM (27.0%). A bigger sample for screening audiometry is required for proper estimation of hearing loss prevalence. Both environmental and genetic factors may have increased the prevalence of CSOM in the Ati population of Boracay.   Keywords:     Hearing loss, chronic suppurative otitis media, Boracay, indigenous community, Ati, Aeta

405: Previous History of Bladder Cancer is an Independent Prognostic Factor for Upper Tract Transitional Cell Carcinoma

2007 ◽  
Vol 177 (4S) ◽  
pp. 135-135
Author(s):  
Eiji Kikuchi ◽  
Akira Miyajima ◽  
Ken Nakagawa ◽  
Mototsugu Oya ◽  
Takashi Ohigashi ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Prognostic Factor ◽  
Transitional Cell Carcinoma ◽  
Cell Carcinoma ◽  
Transitional Cell ◽  
Previous History ◽  
Independent Prognostic Factor ◽  
Upper Tract ◽  
History Of

Popliteal artery thrombosis secondary to a tibial osteochondroma

VASA ◽  
2011 ◽  
Vol 40 (3) ◽  
pp. 251-255 ◽  
Author(s):  
Gruber-Szydlo ◽  
Poreba ◽  
Belowska-Bien ◽  
Derkacz ◽  
Badowski ◽  
...  
Keyword(s):  
Case Report ◽  
Magnetic Resonance Angiography ◽  
Popliteal Artery ◽  
Doppler Ultrasonography ◽  
Histopathological Examination ◽  
Previous History ◽  
Plain Radiography ◽  
Artery Thrombosis ◽  
History Of ◽  
The Right

Popliteal artery thrombosis may present as a complication of an osteochondroma located in the vicinity of the knee joint. This is a case report of a 26-year-old man with symptoms of the right lower extremity ischaemia without a previous history of vascular disease or trauma. Plain radiography, magnetic resonance angiography and Doppler ultrasonography documented the presence of an osteochondrous structure of the proximal tibial metaphysis, which displaced and compressed the popliteal artery, causing its occlusion due to intraluminal thrombosis..The patient was operated and histopathological examination confirmed the diagnosis of osteochondroma.

Rhabdomyolysis in DOMS

1999 ◽  
Vol 38 (05) ◽  
pp. 164-168 ◽  
Author(s):  
Gloria Ruiz Hernandez ◽  
C. Sanchez Marchori ◽  
J. Munoz Moliner ◽  
C. Martinez Carsi
Keyword(s):  
Bone Scintigraphy ◽  
Previous History ◽  
Biochemical Studies ◽  
History Of ◽  
Increased Activity

SummaryA 26-year-old man with a previous history of external twin bursitis was remitted to our Department for a bone scintigraphy. Before the study, the patient performed an elevated number of intense sprints. Bone scintigraphy showed a bilaterally increased activity in both anterior rectum muscles suggesting rhabdomyolysis. Biochemical studies and MRT confirmed the diagnosis.

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