PROTEINURIA
P
STEPS IN PROTEIN SYNTHESIS
Proteins consist of one or more subunits, which are called polypeptides. These
are formed, within cells, from building blocks called amino acids, which are
provided to each cell as raw materials. The instructions for making polypeptides
are encoded in the DNA that is present within the cell nucleus.
I
To make a specific protein or
polypeptide, DNA separates into
two strands and acts as a template to
make a strand of a substance called
messenger RNA. Like DNA, this consists
ofa string of substances called
nucleotide bases.
DNA
Nucleus
M essenger RNA
Ribosome
Cell
Nucleus
DNA
Cytoplasm
2
The messenger RNA
passes out of the cell
nucleus into the cytoplasm,
where it is latched on to by
several decoding particles
called ribosomes. Starting
atone end, the ribosomes
travel along the RNA strand.
3
As it moves along the RNA, each ribosome
connects a chain of amino acids, using
special chemical “keys” (called transfer RNAs)
within the cell. The correct order of the amino
acids is coded by the sequence of bases in the
messenger RNA.
4
At the end of the messenger RNA strand, the
ribosome parts from the amino acid chain, which
folds up to form the finished polypeptide or protein.
p ro te in u ria
T h e p r e s e n c e o f
p ro te in
i n t h e
u rin e .
I t
m a y r e s u l t f r o m k i d n e y d i s o r d e r s , s u c h
a s
g lo m e ru lo n e p h r it is
a n d
u r in a r y tra ct
in fe c tio n .
P r o t e i n u r i a
m a y
a l s o
o c c u r
b e c a u s e o f a g e n e r a l i z e d d i s o r d e r t h a t
c a u s e s i n c r e a s e d p r o t e i n i n t h e b l o o d . I t
i s d i a g n o s e d b y
u rin a ly s is .
P ro th ia d e n
A
b r a n d
n a m e
f o r
t h e
a n t i d e p r e s s a n t
d r u g
d o s u le p in .
p ro th ro m b in tim e
A f o r m o f
b lo o d -c lo t tin g test.
T h e c o n v e r -
s i o n o f p r o t h r o m b i n t o t h r o m b i n i s o n e
o f t h e c h e m i c a l r e a c t i o n s t h a t t a k e s p l a c e
d u r i n g t h e p r o c e s s o f
b lo o d clo ttin g .
T h i s
r e a c t i o n d e p e n d s o n t h e p r e s e n c e o f c l o t -
t i n g f a c t o r s t o g e t h e r w i t h c a l c i u m a n d a
s u b s t a n c e c a l l e d t h r o m b o p l a s t i n . I f c a l c i -
u m
a n d
t h r o m b o p l a s t i n
a r e
a d d e d
t o
a s a m p l e o f b l o o d , i t s h o u l d c l o t w i t h i n a
c e r t a i n
t i m e .
A
c l o t t i n g
t i m e
t h a t
i s
a b n o r m a l l y s l o w i n d i c a t e s a d e f i c i e n c y o f
c l o t t i n g f a c t o r s , a s o c c u r s i n s o m e l i v e r
d i s e a s e s a n d i n v i t a m i n K d e f i c i e n c y . T e s t s
t o m e a s u r e p r o t h r o m b i n t i m e a r e u s e d
t o m o n i t o r p e o p l e u n d e r g o i n g t r e a t m e n t
w i t h
w a rfa rin
( a n
a n tic o a g u la n t d ru g
) . ( S e e
a l s o
In te rn a tio n a l N o rm a liz e d R a tio .)
p ro to n p u m p in h ib ito rs
A t y p e o f
u lc e r-h e a lin g d ru g ,
f o r e x a m p l e
o m e p r a z o l e ,
t h a t i s u s e d i n
t h e
t r e a t -
m
e n t o f
p e p t ic u lc e rs.
p ro to p la sm
A t e r m f o r t h e e n t i r e c o n t e n t s o f a
c e ll.
p ro to z o a
T h e
s i m p l e s t ,
m o s t
p r i m i t i v e
t y p e
o f
a n i m a l , c o n s i s t i n g o f a s i n g l e c e l l . P r o -
t o z o a a r e b i g g e r t h a n
b a c t e ria
b u t s t i l l
m i c r o s c o p i c . A b o u t 3 0 t y p e s a r e h u m a n
p a r a s i t e s ,
i n c l u d i n g
t h o s e
r e s p o n s i b l e
f o r
m a la ria
,
a m o e b ia s is
,
g ia r d ia s is
,
s le e p -
in g s ic k n e s s
,
t ric h o m o n ia s is
,
t o x o p la s m o sis
,
a n d
le is h m a n ia s is .
p ro x im a l
A t e r m
d e s c r i b i n g a p a r t o f t h e b o d y
n e a r e r t o a c e n t r a l p o i n t o f r e f e r e n c e ,
s u c h a s t h e t r u n k . ( S e e a l s o
d is ta l.)
P ro za c
A
b r a n d
n a m e
f o r
t h e
a n t i d e p r e s s a n t
d r u g
flu o x e tin e .
p ru rig o
T h i c k e n i n g a n d
it c h in g
o f t h e
s k in
d u e
t o r e p e a t e d s c r a t c h i n g .
634
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