3 research outputs found
Intracellular Replication of Choleraphage Ê92
The broad host range choleraphage Ê92 contains a linear
double-stranded DNA molecule of 68 kilobase (kb) pairs
with 3) overhang cohesive ends. Following infection with
phage Ê92, the host macromolecular synthesis is shut off
within the first 5 min, and synthesis of phage-specific
DNA is detectable after 7 min of infection. At early times
during infection, phage DNA is replicated in circular form
and the synthesis is membrane associated. The closed
circular form serves as the precursor for the synthesis of
the mature phage DNA which is eventually packaged
into the phage head. Pulse labeling of ultraviolet-irradiated
infected cells at different times during infection
has allowed identification of about 30 phage-specific
proteins of which 6 are structural proteins. These proteins
appear during the infection cycle in two distinct
phases, early and late. Eighteen early and 12 late proteins
have been identified
Ultrastructural and Trace Metal Studies on Radiographers' Hair and Nails
Scalp hair and fingernail samples of 42 medical radiographers
and 42 nonradiographers (control) with matching age groups and
food habits were collected for this study. Trace metal estimation by
atomic absorption spectrometry (AAS) has indicated a significant
increase (P < 0.001) in Zn, Cu, and Cd contents in the radiographers'
hair and nails. Scanning electron microscopy (SEM) reveled structural
changes in the hair and nails of radiographers. Significant alterations
in the Zn and Cd contents along with extensive structural damage in
the hair and nails probably indicate that low-dose X-radiation
imposes stress on these radiation workers