==================================CMR08==================================
8. Key word - Flip-Flop or Flip-Flop Phenomenon.
Seizures which electroencephalographically seem to
begin in one hemisphere, then seem to shift to the other
hemisphere.
1
UI - 87088831
AU - Arima T ; Segawa T ; Nomura Y
TI - Influence of pertussis toxin on the effects of guanine nucleotide
on adenylate cyclase in rat striatal membranes.
AB - The influence of pertussis toxin on the effects of guanine
nucleotide on adenylate cyclase activity were investigated in rat
striatal membranes. GTP promoted and inhibited the activity at 1
and 100 microM, respectively. The inhibitory effects of GTP were
abolished by pretreatment of the membranes with pertussis toxin.
GppNHp (guanyl-5'-y1-beta,gamma-imidodiphosphate) exerted only
stimulatory effects and pertussis toxin did not affect the
effects of GppNHp. GDP at 10 and 100 microM caused significant
inhibition which was completely suppressed by pertussis toxin. It
is suggested that guanine nucleotide regulates the affinity of as
in stimulatory GTP-binding regulatory protein to either beta
gamma or catalytic units of adenylate cyclase in a flip-flop
manner. Inhibitory GTP-binding regulatory protein seems to play a
regulatory role in inhibiting alpha s activity supplying the beta
gamma heterodimer.
MH - Adenyl Cyclase/*METABOLISM ; Animal ; Cell Membrane/METABOLISM ;
Corpus Striatum/*METABOLISM ; Guanine Nucleotide Regulatory
Protein/METABOLISM ; Guanine Nucleotides/*PHARMACODYNAMICS ;
Macromolecular Systems ; Pertussis Toxins/*PHARMACODYNAMICS ;
Rats ; Receptors, Dopamine/*DRUG EFFECTS ; Support, Non-U.S.
Gov't
SO - Life Sci 1986 Dec 22;39(25):2429-34
2
UI - 87028966
AU - Shih WJ ; DeLand FH ; Domstad PA
TI - Flip-flop phenomenon in radiohippuran renal imaging. A sign of
obstructive nephropathy.
AB - In the dynamic radionuclide brain study, decreased flow in one
cerebral hemisphere during the arterial phase followed by
relatively increased radioactivity as compared with the
contralateral hemisphere has been termed the flip-flop
phenomenon, and reflects the development of collateral
circulation to the affected side. In I-131 Hippuran renal
imaging, relatively decreased activity in one kidney frequently
is observed during the initial phase of the study, and is
followed by a gradual increase of radioactivity in the late
images when compared with the contralateral kidney. To evaluate
the significance of this renal flip-flop phenomenon, the studies
from 23 patients with these findings were retrospectively
compared with the clinical data and findings from other
diagnostic studies (CT, ultrasound, intravenous pyelogram,
autopsy). Partial obstruction of the renal collecting system was
found in all 23 patients. The causes were various malignant
tumors in nine patients (colonic carcinoma, three patients;
transitional cell carcinoma, three patients; prostatic carcinoma,
two patients; seminoma, one patient), ureteropelvic obstruction
in three patients, papillary necrosis in one patient, and
ureteral fibrosis in one patient. The flip-flop phenomenon
reflects asymmetric renal tubular function with decrease
(prolonged parenchymal transit time) in the affected kidney as a
result of ipsilateral obstruction of the collecting system, while
contralateral renal function remains normal or relatively normal.
The presence of the flip-flop phenomenon in an I-131 Hippuran
renal study suggests the existence of some degree of collecting
system obstruction that has persisted long enough to result in
renal parenchymal damage.
MH - Comparative Study ; DTPA/DIAGNOSTIC USE ; Human ; Iodohippuric
Acid/*DIAGNOSTIC USE ; Kidney Diseases/*RADIONUCLIDE IMAGING ;
Kidney Neoplasms/RADIONUCLIDE IMAGING ; Kidney Papillary Necrosis/
RADIONUCLIDE IMAGING ; *Radioisotope Renography ; Technetium/
DIAGNOSTIC USE ; Tomography, X-Ray Computed ; Ultrasonic
Diagnosis ; Ureteral Diseases/RADIONUCLIDE IMAGING ; Ureteral
Obstruction/RADIONUCLIDE IMAGING ; Urography
SO - Clin Nucl Med 1986 Oct;11(10):707-12
3
UI - 86162622
AU - Verreault J ; C:ot:e C
TI - Flip-flop phenomenon and dissection of extracranial carotid
artery.
AB - A case of extracranial carotid artery dissection investigated
both by conventional brain imaging and by arteriography is
presented. The radionuclide angiogram showed a flip-flop
phenomenon on the left hemisphere. The implications, including
clinical features, pathogenesis, diagnosis, and treatment are
discussed. Dissection of extracranial carotid artery is a cause
of carotid hypoactivity, and this phenomenon is associated
directly with a flip-flop phenomenon on brain imaging.
MH - Aneurysm, Dissecting/*DIAGNOSIS/RADIOGRAPHY/RADIONUCLIDE IMAGING
; Carotid Artery Diseases/*DIAGNOSIS/RADIOGRAPHY/RADIONUCLIDE
IMAGING ; Carotid Artery, External ; Case Report ; Cerebral
Angiography ; Human ; Male ; Middle Age ; Sugar Acids/DIAGNOSTIC
USE ; Technetium/DIAGNOSTIC USE
SO - Clin Nucl Med 1986 Apr;11(4):251-3
4
UI - 86112699
AU - McCormack J ; Peyster RG ; Brodner RA ; Cooper VR
TI - CT visualization of ruptured berry aneurysm within hematoma: the
flip-flop sign.
AB - Postcontrast CT of the head may be a useful screening technique
for identifying an aneurysm within an intracerebral hematoma.
This could avoid unnecessary angiography with its attendant
morbidity in inoperable situations and obviate initial
arteriography in patients whose surgery is to be delayed.
MH - Adult ; Case Report ; Cerebral Aneurysm/*RADIOGRAPHY ; Cerebral
Hemorrhage/*RADIOGRAPHY ; Hematoma/*RADIOGRAPHY ; Human ; Male ;
Middle Age ; Rupture, Spontaneous ; *Tomography, X-Ray Computed
SO - J Comput Assist Tomogr 1986 Jan-Feb;10(1):28-31