vibrio cholerae o1 are classified into two biotypes, classical and el tor based on susceptibility to bacteriophages and some biochemical properties, each encoding a biotype-specific genetic determinants. before 1961, most epidemics had been caused by the classical biotype. however, with the passage of time, the classical biotype missed from the scenario and the el tor emerged as the major bioty...

Considering the recent emergence of "hybrid biotype" and "El Tor variant", we propose to redefine the biotyping scheme for Vibrio cholerae O1 serogroup. The existing biotyping scheme has limitations and causes confusion as many of the hybrid biotype and El Tor variant strains have phenotypic and genetic changes. A revised biotyping scheme will play a significant role to understand the ecology, ...

Vibrio cholerae is the causative agent of cholera, a life threatening and watery diarrhoea that causes an estimated 3–5 million cholera cases and100000–120000 deaths per year (Zuckerman et al., 2007). The current pandemic of cholera is caused by El Tor biotype of the O1 serotype distinct from the classical biotype that is responsible for the previous pandemics. Recently, V. cholerae strains iso...

To the Editor: The traditional causative agent of cholera, Vibrio chol-erae O1, has 2 biotypes, classical and El Tor. The current seventh pandemic that began in 1961 and has spread to much of the world is caused by the El Tor biotype. This biotype has replaced the classical biotype responsible for the previous pandemics. The classical and El Tor biotypes are differentiated by phenotypic tests (...

BACKGROUND & OBJECTIVES El Tor Vibrio cholerae O1 carrying ctxB C trait, so-called El Tor variant that causes more severe symptoms than the prototype El Tor strain, first detected in Bangladesh was later shown to have emerged in India in 1992. Subsequently, similar V. cholerae strains were isolated in other countries in Asia and Africa. Thus, it was of interest to investigate the characteristic...

Background and Aim: Several methods have been suggested to measure gingival thick-ness. This study aimed to assess the reliability of visual assessment of facial gingival biotype of maxillary and mandibular teeth with or without using a periodontal probe in comparison with direct measurement. Materials and Methods: Sixty-seven healthy patients (25 women and 42 men) with a total of 100 hopele...

A total of 330 clinical Vibrio cholerae O1 serogroups from China dating between 1961 and 2010 were investigated. By phenotypic biotyping and genetic analysis, during the seventh pandemic of V. cholerae O1 in China, the isolates of hybrid biotype (mixed classical phenotypes) were present during the entire1961-2010 period, while El Tor genetic shifts appeared in 1992 and replaced the prototype El...

Background: Gingival biotype is one of the most important factors that impede success in dental treatments; it affects the outcomes of periodontal surgery, and restorative treatments. Researchers classified gingival biotypes into thin biotype and thick biotype. It is crucial to identify tissue biotype before treatment. Aim of Study: To determine the prevalence of gingival biotypes in a Syrian p...

Forty-five enteropathogenic (enteropathogenic Escherichia coli-like) strains isolated in commercial rabbit farms were subdivided into four biotypes with the help of six carbohydrate fermentation tests, ornithine decarboxylase tests, and motility tests. E. coli strains which caused neonatal diarrhea in baby rabbits belonged to a single biotype, biotype 1, and displayed the same serotype antigens...

Sexual, tetraploid (2n = 4x = 40) vaseygrass (Paspalum urvillei Steud.) was crossed with two apomictic, hexaploid (2n = 6x = 60) dallisgrass (P. dilatatum Poir.) biotypes (Uruguayan and Uruguaiana) to determine their relationships and the reproductive behavior of the hybrids. One vaseygrass x Uruguayan and two vaseygrass x Uruguaiana hybrids were studied and all had 2n = 5x = 50 chromosomes. Th...