Intermediate filament proteins.
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Amino Acid Sequence↗
Biomedical subjects
B Lane
Publications and source records attributed to B Lane.
Decidualization of human endometrial stromal cells in vitro: effects of progestin and relaxin on the ultrastructure and production of decidual secretory proteins.
Decidual cells arise by proliferation and differentiation of endometrial stromal cells of the uterus after appropriate stimulation by ovarian hormones. Previously we have shown that progestin and relaxin stimulate the secretion of several decidual-cell-specific secretory proteins in a long-term primary cell culture system. We now report the effects of progestin and relaxin on the morphology of stromal cells in association with the production rate of two major decidual secretory proteins, prolactin and insulin-like growth factor binding protein-1 (IGFBP-1). Stromal cells were cultured in RPMI 1640 and 2% fetal bovine serum for 22 days under control conditions (no hormone), with relaxin or medroxyprogesterone acetate (MPA), or MPA plus relaxin. Cells treated with MPA alone or MPA plus porcine relaxin grew to a high density with many areas of heaping while control cells and cells grown in medium containing relaxin alone formed discontinuous layers. The cytoplasm was distinguished by aggregates of rough endoplasmic reticulum and secretory granules. Surfaces of cells treated with MPA plus relaxin had clusters of short blunt processes containing secretory granules. The processes were rarely seen in cells exposed to MPA alone and completely absent in control cells or cells exposed to relaxin alone. Intercellular space was greatly widened in cells treated with MPA alone or MPA plus relaxin. There were many extended gap junctions in MPA- and relaxin-treated cells in contrast to controls.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Neuroradiology.
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Central Nervous System Diseases↗
Stent placement for arterial and venous cerebrovascular disease: preliminary experience.
PURPOSE: To report initial clinical experience with stent placement in the cerebrovascular circulation. MATERIALS AND METHODS: Four patients underwent arterial or venous stent placement. Two patients had cervical internal carotid artery dissections, with aneurysms and stenoses of the distal cervical carotid artery. Two patients had venous occlusive disease involving the major dural sinuses, with substantial pressure gradients across the stenoses. RESULTS: Immediately after stent placement, the true arterial lumina returned to normal diameter and both carotid aneurysms were more than 90% occluded. Follow-up angiography demonstrated continued improvement in the arterial aneurysms. Both patients with dural sinus venous occlusive disease showed substantial improvement of the sinus stenoses and substantial reversal of the pressure gradients after venous stent placement. At follow-up, these patients have done well. CONCLUSION: This preliminary experience suggests there may be a role for stents in the management of arterial and venous cerebrovascular disease, including carotid artery dissection and venous occlusive disease.
Adult↗
Intermediate filament proteins.
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Amino Acid Sequence↗
Correlation of pressure measurements with angiographic characteristics predisposing to hemorrhage and steal in cerebral arteriovenous malformations.
PURPOSE: To determine whether there is a physiologic explanation for the predisposition of patients with certain angiographic characteristics to symptoms of hemorrhage and steal. METHODS: Superselective transcatheter feeding arterial pressure and mean arterial pressure measurements were obtained before embolotherapy in 32 patients with cerebral arteriovenous malformations. Pressures were correlated with previously described angioarchitectural characteristics predisposing to hemorrhage and steal. These included size of the arteriovenous malformation, feeding artery length, venous drainage pattern, and angiomatous change. RESULTS: The feeding arterial pressure and feeding arterial pressure/mean arterial pressure ratios were significantly decreased in patients with angiomatous change. Feeding arterial pressure and feeding arterial pressure/mean arterial pressure ratios progressively decreased as lesions went from peripheral, to mixed, to central venous drainage. A trend for lower feeding arterial pressure was also demonstrated with greater feeding pedicle length. A statistically significant correlation could not be demonstrated between feeding arterial pressure or feeding arterial pressure/mean arterial pressure ratios and size of the arteriovenous malformation, hemorrhage, or symptoms of steal. CONCLUSIONS: Feeding arterial pressure measurements help provide a physiologic basis for the relationship between certain angiographic characteristics and hemorrhage and steal symptoms in patients with arteriovenous malformation.
Adolescent↗
A mechanically detachable coil for the treatment of aneurysms and occlusion of blood vessels.
PURPOSE: To evaluate mechanically detachable coil designs capable of controlled and instantaneous release within an aneurysm or vascular space. METHODS: Three mechanically detachable coil designs, clamped ball, looped ribbon, and interlocking cylinder, were evaluated using in vitro and in vivo testing to study reliability of coil release, retractability, and coil behavior in a microcatheters. In vitro tests were performed using a glass side-wall aneurysm model and conventional microcatheters. In vivo experiments in rabbits included aneurysm models (side-wall and bifurcation) and arterial occlusions (carotid and renal). RESULTS: All three designs deployed coils easily and were able to retract coils after partial deployment. Motion was seen in previously released coils and in the catheter when using the clamped ball and looped ribbon designs. The interlocking cylinder design did not cause similar motion. When compared with the other two designs, the interlocking cylinder had significantly greater separation forces between coil pusher and coil while in the catheter. Frictional forces within the catheter were lower for the interlocking cylinder mechanically detachable coil design than for a commercially available conventional coil and coil pusher system. During in vivo testing, the mechanically detachable coil design operated smoothly in the catheter, providing good release and retraction in aneurysms and straight vessels. CONCLUSION: The interlocking cylinder mechanically detachable coil design is superior to the other two tested designs. The mechanically detachable coil was reliably delivered and detached in in vivo testing for the treatment of aneurysms and for the occlusion of blood vessels.
Animals↗
Selective cholangiography in laparoscopic cholecystectomy.
Laparoscopic cholecystectomy is now the method of choice for removing the diseased gallbladder. Asymptomatic common bile duct stones occur in approximately 6 per cent of patients. Controversy exists, however, as to whether selective or routine peroperative cholangiography should be performed during laparoscopic cholecystectomy. Over a 21-month period 300 consecutive laparoscopic cholecystectomies without routine cholangiography were attempted. There were 28 conversions. In all, 229 patients did not undergo cholangiography and in this group there were two common duct injuries. These were both identified and dealt with by open operation. Five patients underwent peroperative cholangiography, none of whom was found to have common duct pathology. Endoscopic retrograde cholangiopancreatography was performed in 38 patients. Of 27 who had this investigation performed before operation, common duct stones were diagnosed in seven (26 per cent). Two common duct stones were discovered in 11 patients who underwent the investigation after operation. Thus only two of 240 patients (0.8 per cent) who did not undergo preoperative or peroperative cholangiography subsequently had symptomatic duct stones. Peroperative cholangiography may be indicated in selected patients who have had symptoms of common bile duct stones or in those in whom the biliary anatomy is unclear. However, routine preoperative or peroperative cholangiography is unnecessary during laparoscopic cholecystectomy.
Adolescent↗
FKBP12-FK506 complex inhibits phosphatase activity of two mammalian isoforms of calcineurin irrespective of their substrates or activation mechanisms.
The interaction of calcineurin (Ca2+/calmodulin-dependent protein phosphatase) with the potent immunosuppressive agent FK506 and its 12 kDa isoform binding protein (FKBP12) was investigated. The FKBP12-FK506 complex inhibited the Ca2+/calmodulin-stimulated phosphatase activity of each of two calcineurin isoforms, which contain either the catalytic subunit A alpha or A beta (calcineurin A alpha or A beta) of bovine calcineurin. Calcineurin phosphatase activity was inhibited by the FKBP12-FK506 complex irrespective of the substrate or the enzyme activation mechanism. FK506 and FKBP-12 inhibited calcineurin in a concentration-dependent manner, and complete inhibition of the phosphatase activity appeared to require a molar excess of FKBP12-FK506 complex. Immunochemical measurements revealed tissue differences in the concentration of calcineurin, which may be of importance to the selectivity for immunosuppression of all of the biological effects. Direct binding studies with [3H]dihydro-FK506 suggest that the ratio of FKBP12-FK506 complex to calcineurin in vivo when IL2 production is inhibited is well correlated with the ratio when calcineurin phosphatase activity is inhibited in vitro. These results suggest that calcineurin is a relevant cellular target of FK506 when bound to FKBP-12.
Amino Acid Sequence↗
Intracellular localization of polymerase chain reaction (PCR)-amplified hepatitis C cDNA.
The cellular distribution of hepatitis C virus was examined in formalin-fixed, paraffin-embedded tissues by in situ localization of the polymerase chain reaction (PCR)-amplified viral cDNA. Of nine liver biopsies studied, five were from patients seropositive for hepatitis C, one was from a seronegative patient who had detectable hepatitis C cDNA by standard reverse transcriptase (RT) PCR, and the remaining three were from patients without evidence of hepatitis C infection. Sequences homologous to viral RNA were rarely identified in the hepatitis C cases by standard RNA-cDNA in situ hybridization, but PCR-amplified viral cDNA was detectable in many hepatocytes in a panlobular distribution and in scattered Kupffer cells in each of the six hepatitis C cases and none of the controls. The pattern was equivalent whether intracellular localization was done by in situ hybridization after the RT and PCR steps or if digoxigenin-labeled nucleotide was incorporated into the amplified product. No signal was evident in the positive biopsies if the RT step was omitted, if "nonsense" primers were used, or if RT in situ PCR was preceded by RNase digestion. The RT in situ PCR technique allows for the rapid detection of any RNA virus, even if it is present in low copy number, and permits direct morphological correlation.
Base Sequence↗
Nuclei that lack a lamina accumulate karyophilic proteins and assemble a nuclear matrix.
Xenopus egg extracts, which support nuclear assembly and DNA replication in vitro, were physically depleted of lamin B3 using monoclonal antibodies linked to magnetic beads. Depleted extracts were still able to support nuclear envelope assembly around demembranated sperm heads but the resulting pronuclei lacked a lamina and were unable to initiate semiconservative DNA replication or to assemble replicases, confirming previous data. Immunoblotting analysis of isolated nuclei and nuclear matrix fractions indicated that lamin-depleted nuclei still accumulated nucleoporins and PCNA. Furthermore, the rate of PCNA uptake was identical in lamin-depleted and control nuclei. However, neither the nucleoporins nor the PCNA was associated with nuclear matrix fractions. The major protein components of sperm pronuclear matrix fractions were characterized by two-dimensional gel electrophoresis. Of these proteins only three out of 22 species, other than the lamins, were significantly reduced in lamin-depleted nuclei, indicating that these nuclei do assemble a nuclear matrix.
Animals↗
Interventional neuroradiology--a new approach to difficult vascular lesions of the brain.
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Cerebrovascular Disorders↗
Structure-function studies in a series of carboxyl-terminal octapeptide analogues of anaphylatoxin C5a.
The synthesis and structure-activity relationships of C-terminal octapeptide analogues of anaphylatoxin C5a have been studied. The introduction of hydrophobic amino acids into the N-acetylated native octapeptide (N-Ac-His-Lys-Asp-Met-Gln-Leu-Gly-Arg-OH) (1) has led to an analogue with 100 times more activity than the native octapeptide in inhibiting the binding of 125I-labeled anaphylatoxin C5a to human neutrophil membrane receptors. The observed apparent binding Ki's for the compounds (8-10) are in the range of 1-3 microM, and they possess nearly full agonist activity, despite the fact that these analogues are one-eighth or -ninth the size of the natural ligand anaphylatoxin C5a.
Amino Acid Sequence↗
Improvements in the minimum binding sequence of C5a: examination of His-67.
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Amino Acid Sequence↗
Altered surface character of stretched condom latex.
A new type of imperfection in condom latex, present during moderate stretching, was observed by low magnification scanning electron microscopy. The normally smooth surface of relaxed natural latex was transformed into an accordion-like arrangement of ripples in addition to tears. A corollary experiment with Alcian blue dye placed into both stretched and unstretched condoms leaked no dye. These surface features are consistent with latex acting as a molecular barrier. The tears may represent areas of lowered mechanical resistance and raise questions concerning quality control.
Contraceptive Devices, Male↗
Cytokeratin and vimentin heterogeneity in human cornea.
The body of information on cytokeratin expression in non-epithelial and epithelioid cells is steadily increasing. In this immunocytochemical study using a panel of monoclonal cytokeratin antibodies, we regularly observed cytokeratins no. 8 and 18 together with vimentin in the corneal endothelium of the human eye, but the antibodies exhibited a heterogeneous reactivity pattern. In fetal eye specimens, cytokeratins were already present at the 10th week of gestation, and disappeared at about the 22th week of fetal development. Corneal and conjunctival epithelial cells in the same specimens usually showed uniform cytokeratin 8 and 18 expression, beside the well documented presence of corneal and squamous epithelium type cytokeratins. In 2 of our 7 cases of adults, cells coexpressing cytokeratin and vimentin were observed in the corneal epithelium. The data provide another example of modulation of cytokeratin and vimentin expression, in which simplistic rules cannot be applied.
Adult↗
Brain gray and white matter volume loss accelerates with aging in chronic alcoholics: a quantitative MRI study.
Magnetic resonance imaging (MRI) was used to study in vivo the brains of 49 patients with chronic alcoholism, 3 to 4 weeks post-withdrawal, and 43 normal healthy controls, all right-handed male veterans between the ages of 23 and 70 years. MRI scans were analyzed using a semi-automated procedure, which allowed the subcortical regions to be segmented into cerebrospinal fluid (CSF) and brain tissue and the cortical regions to be segmented into CSF, gray matter, and white matter. An age regression model was used to examine the effects of alcohol on brain structure, over and above that expected from the normal aging process. The alcoholics exhibited decreased tissue and increased CSF after correcting for aging. In the cortex, there was significant loss of both gray matter and white matter volume. In this sample of alcoholics, no particular cortical region was preferentially affected or spared. Furthermore, brain tissue volume loss increased with advanced age in the alcoholics. In this group of alcoholics there was no relationship between length of illness and age, i.e., the younger alcoholics had as heavy alcohol use histories as did the older alcoholics. Thus, the increased brain tissue loss with advanced age is interpreted as evidence for age-related increase in brain vulnerability to chronic alcohol abuse.
Adult↗
Intranidal aneurysms in cerebral arteriovenous malformations: evaluation and endovascular treatment.
Patients with cerebral arteriovenous malformations (AVMs) have an increased risk of hemorrhage if an intranidal aneurysm is present. Angiograms from 125 patients with cerebral AVMs were evaluated, and 15 (12%) had intranidal aneurysms. All 15 patients had a history of bleeding. Five patients underwent particulate or liquid embolization before surgical excision of or radiation therapy for the AVM. All aneurysms were thrombosed at the time of embolization. Ten patients underwent radio-surgery alone. Eight of the 10 underwent angiographic follow-up (mean, 33 months); seven patients showed complete obliteration of the AVM without residual aneurysm. Histologic evaluation showed intranidal aneurysms to be thin-walled vascular structures, and they are the likely site for AVM hemorrhage. Embolization is an effective method for achieving thrombosis of the intranidal aneurysm and may be beneficial in patients undergoing radiation therapy because of a long latency period between treatment and thrombosis of the AVM.
Adolescent↗