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PubMed2000

Safety of extraovular catheter insertion for second-trimester abortion.

OBJECTIVE: To evaluate the efficacy and safety of second-trimester abortions using transcervical catheter insertion and extraovular prostaglandin (PG) administration. METHODS: Ninety women admitted for terminations of pregnancy at 17-24 weeks' gestation had transcervical catheters inserted and extraovular PGE(2) administered. Success rates were recorded, measured by induction of abortion within 24 hours, need for a complement uterine curettage, and complications. RESULTS: The technique induced abortion in 67 women (74.4%). The induction-to-abortion median interval was 12 hours (7 and 22 hours, fifth and 95th percentiles, respectively). Thirty-seven women needed uterine curettages because of incomplete abortions or excessive uterine bleeding after fetal and placenta expulsion. One woman had shivering, weakness, and nausea attributed to systemic absorption of PG, and nine women developed systemic inflammatory response syndrome associated with transcervical catheter insertion. Two of those women had septic shock, one of whom deteriorated to a life-threatening situation. CONCLUSION: Transcervical catheter insertion for extraovular PG administration is effective for inducing second-trimester abortions. Although the method is considered safe, with generally few mild, treatable complications, we observed a high rate of systemic inflammatory response syndrome, bacteremia, and sepsis caused by transcervical catheter insertion before PG administration. A reconsideration of this method's safety is warranted.

Abortion, Induced↗
PubMed2001

Dinoprostone vaginal insert for cervical ripening and labor induction: a meta-analysis.

OBJECTIVE: To compare dinoprostone 10 mg controlled-release vaginal insert with other forms of vaginal or cervical prostaglandin for cervical ripening. DATA SOURCES: Literature search strategy included review of the Cochrane database of randomized trials, on-line searching of MEDLINE, hand searching of bibliographies, and contact with authors of relevant reports. METHODS OF STUDY SELECTION: Randomized trials were included if they compared a dinoprostone slow-release vaginal insert with an alternative vaginal or cervical prostaglandin for cervical ripening and labor induction in women at term with singleton gestations. Primary end points were delivery by 24 hours postinsertion, uterine hypertonus with fetal heart change, and cesarean delivery rate. Study inclusion, validity assessment, and data extraction were carried out independently by two reviewers, and cross-checked for consistency. Data were combined when appropriate, using the Mantel-Haenszel fixed-effects method. Statistical heterogeneity was assessed using chi-square statistics. TABULATION, INTEGRATION, AND RESULTS: Nine relevant trials were identified, seven comparing the dinoprostone 10 mg vaginal insert with dinoprostone gel and two with misoprostol. Five trials reported adequate methods for randomization concealment. None were double blind. The likelihood of delivery by 24 hours was similar with the vaginal insert and alternatives: common odds ratio (OR) 0.80 (95% confidence interval [CI] 0.56, 1.15). Uterine hypertonus with change in fetal heart and cesarean delivery rate were also similar: common OR 1.19 (95% CI 0.56, 2.54) and 0.78 (95% CI 0.56, 1.08), respectively. The secondary end points of mean time to delivery and delivery by 12 hours appeared to favor misoprostol-dinoprostone gel. However, data for these end points were heterogeneous and their combination is therefore of limited value and potentially misleading. CONCLUSION: No clinically significant differences were identified between the vaginal insert and alternatives used for cervical ripening at term.

Administration, Intravaginal↗
PubMed1996

Effectiveness of a urinary control insert in the management of stress urinary incontinence: early results of a multicenter study.

OBJECTIVES: The purpose of this study was to test the safety and effectiveness of a urethral insert for managing stress or mixed urinary incontinence. METHODS: We performed a prospective, multicenter study of 135 female patients who were treated for 4 months with the Reliance Urinary Control Insert. The effectiveness of the insert was measured objectively at the time of first use and after 4 months' use by standardized pad weight studies. Insert effectiveness was also measured by reports of symptom improvement during patient interviews and on patient diaries. Urine microscopy and culture were obtained monthly; cystoscopy and urodynamics were conducted at study entry and at 4 months. RESULTS: Significant improvement in involuntary urine loss was observed. Objective measurement of urine loss revealed that 80% of the patients were completely dry, and 95% of the patients achieved greater than an 80% decrease in urine loss. In addition, patients' perceptions of acceptability, incontinence symptom improvement, ease of learning, comfort, and time to habituation also showed improvements. Untoward events reported during the study included hematuria, bacteriuria, and bladder irritation. These events did not require significant medical intervention and did not result in any long-term clinical sequelae. CONCLUSIONS: These preliminary results indicate that the Reliance Urinary Control Insert may be a safe, effective, and well-tolerated alternative to other available methods for the management of stress or mixed incontinence in women. Additional long-term follow-up will be required to substantiate this conclusion.

Adolescent↗
PubMed1994

SecA promotes preprotein translocation by undergoing ATP-driven cycles of membrane insertion and deinsertion.

SecA, the peripheral subunit of E. coli preprotein translocase, alternates between a membrane inserted and a deinserted state as part of the catalytic cycle of preprotein translocation. When SecA is complexed with SecY/E and preprotein, ATP drives a profound conformational change, leading to membrane insertion of a 30 kDa domain of SecA. The inserted domain is protease-inaccessible from the cytosolic side of the membrane, but becomes accessible upon membrane disruption. Concomitant with 30 kDa domain insertion, approximately 20 aminoacyl residues of the preprotein are translocated. Additional ATP, which may be hydrolyzed at the second ATP site of SecA, releases the translocated preprotein and allows the 30 kDa domain to deinsert, whence it can exchange with cytosolic SecA. Thus, SecA is the mobile subunit of an integral membrane transporter, consuming ATP during both the insertion and deinsertion phases of its catalytic cycle while guiding preprotein segments across the membrane.

Adenosine Triphosphatases↗
PubMedDate not supplied

The effect of suction catheter insertion and tracheal stimulation in adults with severe brain injury.

OBJECTIVE: To determine the effect of suction catheter insertion and tracheal stimulation on cerebrovascular and systemic vascular status in adults with severe traumatic brain injury. DESIGN: Quasi-experimental, within-subject design. SETTING: Two university-affiliated critical care units. SUBJECTS: Thirty intubated and mechanically ventilated adults with severe brain injury. The participants' average age was 31 +/- 15 years. OUTCOME MEASURES: Mean intracranial pressure (MICP), mean arterial pressure (MAP), cerebral perfusion pressure (CPP), and heart rate (HR) were measured. INTERVENTION: Endotracheal suction catheter insertion with tracheal stimulation was performed. RESULTS: Suction catheter insertion and tracheal stimulation, isolated from other components of the suctioning procedure, significantly increased MICP, MAP, and CPP. HR was not significantly increased. During the application of negative pressure for actual suctioning, MICP and HR significantly increased, whereas MAP and CPP did not significantly change compared with catheter insertion. CONCLUSION: Tracheal stimulation during suction catheter insertion initiates both cerebrovascular and systemic vascular responses during the suctioning procedure. Study findings suggest that a potentially productive direction for intervention research is to identify ways to minimize airway stimulation during the suctioning procedure.

Adult↗
PubMed2001

Pars plana tube insertion of glaucoma drainage implants and penetrating keratoplasty in patients with coexisting glaucoma and corneal disease.

PURPOSE: To determine the efficacy and associated complications of glaucoma drainage implant (GDI) surgery with pars plana tube insertion and penetrating keratoplasty (PK) in eyes with glaucoma and corneal disease. DESIGN: Retrospective, interventional case series. PARTICIPANTS: All patients who underwent both GDI surgery with pars plana tube insertion and PK before September 1997 were included. METHODS: The medical records of 34 consecutive patients (34 eyes) who had undergone GDI (Baerveldt, Pharmacia & Upjohn, Kalamazoo, MI; Molteno, IOP INC:, Costa Mesa, CA; Krupin, Hood Laboratories, Pembroke, MA; or Ahmed, New World Medical, Rancho Cucamonga, CA) insertion before, concurrent with, or after PK were reviewed retrospectively. All corneal grafts were clear before GDI surgery for patients who underwent glaucoma surgery after PK. Outcomes were evaluated using Kaplan-Meier life-table analysis. MAIN OUTCOME MEASURES: Clinical outcome assessment included corneal graft clarity, intraocular pressure (IOP), visual acuity, and identification of complications. RESULTS: Mean follow-up after completion of both GDI surgery and PK was 12.1 +/- 8.4 months (range, 0-31.8 months). Twelve- and 24-month life-table rates for complete success after both GDI and PK were 63% and 33%, respectively. Twelve- and 24-month life-table success rates for IOP control and corneal graft clarity were 85% and 62%, and 64% and 41%, respectively. Final postoperative visual acuity was the same as or better than (> or =2 Snellen lines) the preoperative level in 29 patients (85%). One or more posterior segment complications occurred in 15 (44%) patients. CONCLUSIONS: Pars plana tube insertion of GDIs is a reasonable option for patients who have undergone PK or in whom PK is anticipated, despite the need for a complete pars plana vitrectomy. Although complications related to limbal tube placement are avoided, the incidence of posterior segment complications may be higher for pars plana insertion. The potential for enhanced corneal graft survival with pars plana versus anterior segment tube placement warrants further investigation.

Adult↗
PubMed2002

Risk factors for self-reported visual symptoms with Intacs inserts for myopia.

OBJECTIVE: Potential risk factors and visual performance measures were evaluated for relationship to self-report of clinical visual symptoms after the refractive procedure for placement of Intacs microthin prescription inserts for myopia. DESIGN: Retrospective nonrandomized comparative study. PARTICIPANTS/INTERVENTION: Patients were participants in the U.S. Food and Drug Administration phase III KeraVision prospective clinical trials. MAIN OUTCOME MEASURES: Study participants (n = 263) were retrospectively classified into one of three outcome groups on the basis of postoperative self-reported visual symptoms and/or request for Intacs inserts removal through month 24. Differences between outcome groups in visual acuity, refractive error, corneal geometry, corneal topography, type of preoperative corrective lens wear, and demographic variables were evaluated with multivariate logistic regression. RESULTS: Clinical trial participants who had preoperative mean keratometry >45 diopters (D) (adjusted odds ratio [OR], 0.43; 95% confidence interval [CI], 0.21, 0.85, P = 0.02), manifest refractive astigmatism of 0.75 D or 1.00 D (adjusted OR, 0.52; 95% CI, 0.25, 1.08, P = 0.08), measured uncorrected visual acuity > or =2 lines better than that predicted by their respective cycloplegic refractive error (adjusted OR, 0.39; 95% CI, 0.14, 1.12, P = 0.08) and/or had worn soft contact lenses (adjusted OR, 0.58; 95% CI, 0.32, 1.04, P = 0.07) tended to be less likely to report postoperative clinical visual symptoms with Intacs inserts. Risk of clinical visual symptoms and request for Intacs inserts removal approximately doubled for each 0.50 D of additional postoperative defocus equivalent (crude OR, 1.86; 95% CI, 1.39, 2.48, P = 0.00). Controlling for postoperative defocus and important preoperative risk factors, subjects who reported significant clinical visual symptoms were more likely to have had preoperative uncorrected visual acuity that was worse than that predicted by their respective cycloplegic refractive error (adjusted OR, 1.84; 95% CI, 0.98, 3.42, P = 0.06). Risk of reporting clinical visual symptoms was increased with mesopic pupil diameter > or =6.5 mm (adjusted OR, 1.76; 95% CI, 0.96, 3.24, P = 0.07). Within the group of patients who reported postoperative clinical visual symptoms, 71 of 122 (58%) had ceased reporting them by month 24. CONCLUSIONS: Adjusting for important risk factors simultaneously, this study suggested that certain preoperative characteristics may increase or decrease the likelihood, depending on the characteristic, of refractive surgery candidates to report significant clinical visual symptoms with Intacs inserts.

Adult↗
PubMed2000

Variability of Eustachian tube function in children with secretory otitis media. Evaluations at tube insertion and at follow-up.

OBJECTIVE: Despite the variable clinical course of diseases related to Eustachian tube function, the variability of tubal function has been less focused than outcomes of single tests. This study aimed to compare the passive and active tubal function and its variability in children with secretory otitis media (SOM) at tube insertion and at follow-up. METHOD: Thirty-eight ears in 19 children aged 4-10 years (mean 7.0 years) with long-standing SOM were examined 4-6 h after tube insertion, at 4 months and at 9 months. The pressure in the middle ear and the nasopharynx were recorded while performing (1) forced opening test, (2) equalization of +100 and -100 daPa, (3) Valsalva test, and (4) sniff test. The procedure was repeated after 30 min. Relationships were analyzed by uni- and multi-variate analysis of variance. RESULTS: From tube insertion to 4 months, the mean forced opening pressure increased from 282+/-128 to 355+/-153 daPa (P<0.01), and the mean closing pressure from 91+/-51 to 126+/-82 daPa (P<0.01). There was no further change at 9 months. Female gender, serous effusion (in contrast to mucoid), and more than three previous episodes of acute otitis media were related to higher opening and closing pressures. At tube insertion, 60% and 16% equalized +100 and -100 daPa, respectively, and 28% succeeded in performing Valsalva inflation. The sniff test was positive in 32%, indicating a closing failure. These rates did not change significantly over time. For individual ears, outcomes of all tests varied considerably when retested after 30 min; P(o) changed by +/-12% and P(c) by +/-26%, and 9-29% of the ears changed from a positive to negative response, or vice versa, in the equalization, Valsalva, and sniff tests. CONCLUSIONS: The unexpected finding of weaker closing forces at the day of tube insertion and increased tubal resistance at follow-up might be ascribed to changes in the muco-adhesive forces related to the disease and tube treatment. The pronounced intra-individual variability of test outcomes indicates that tubal function is dynamic and variable in ears prone to SOM, which emphasizes that results of single tubal function tests have very low prognostic value.

Analysis of Variance↗
PubMed2002

The variable endogenous retroviral insertion in the human complement C4 gene: a transmission study in type I diabetes mellitus.

A variable endogenous retroviral element has been identified in intron 9 of the complement C4 gene [HERV-K(C4)], which maps to the class III region of the major histocompatibility complex (MHC) on chromosome 6p21.3. Genetic susceptibility to type I diabetes is mainly conferred by the MHC locus and the complement C4 region has been implied to contribute to human leukocyte antigen DQ (HLA-DQ) mediated disease risk. As the HERV-K(C4) insertion has been suggested to modulate expression of homologous genes, we investigated its transmission in 220 families with an offspring affected by type I diabetes as a potential disease susceptibility marker. There was no preferential transmission of the HERV-K(C4) insertion to affected offspring (P(TDT) = 0.79). Although 77.7% of HLA-DQ8 carried the HERV-K(C4) insertion, only 52.9% of -DQ2 haplotypes did (P(chi(2)) < 0.01). However, its insertion or deletion did not modulate the risk conferred by HLA-DQ8 (DQA1*0301-DQB1*0302) (P(chi(2)) = 0.27) or -DQ2 (DQA1*0501-DQB1*0201) (P(chi(2)) = 0.46). Thus, the HERV-K(C4) insertion is not associated with type I diabetes in Germans.

Complement C4↗
PubMed2000

[Anterograde insertion of ureteral catheter].

We report twenty-four patients with urinary obstruction, in which twenty-seven antegrade ureteral stent (double J) insertions were attempted (in six patients the obstruction was bilateral and in three other patients we failed). In all of them access to the urinary tract was through a nephrostomy catheter, in seventeen cases we proceeded to insert the antegrade catheter immediately after percutaneous nephrostomy and in ten remaining cases we achieved in a second try after carrying nephrostomy and failing a conventional retrograde approach to ureteral stent insertion. We got a 90-per cent success rate. A case of perirrenal hematoma occurred after applying a nephrostomy. It was the only relevant complication. In conclusion we consider that the antegrade ureteral stent insertion is a good alternative when, under several circumstances, the conventional retrograde insertion fails.

Female↗
PubMed2003

Evaluation of accuracy of insertion of dental implants and prosthetic treatment by computer-aided navigation in minipigs.

The survival of loaded implants is critically dependent on their biomechanical stability. We have used a computer-guided navigation technique to evaluate the accuracy of computer-assisted insertion for immediately-loaded implants in minipigs. On the basis of computed tomographical data, the Robodent system was used for preoperative planning and guidance of inserting the implant. An optical tracking system allowed positioning of the implant and immediate prosthetic rehabilitation by inserting it in a plaster model and during the operation. Postoperative computed tomograms (CT) showed that the implants were placed precisely in the preoperatively planned position. The accuracy achieved corresponded well with the spatial resolution of the CT used. Immediate placement of the prefabricated crowns resulted in favourable occlusal positioning. Histological cross-sections showed that the implants were biomechanically stable. The accuracy of insertion of oral implants illustrated here suggests that insertion and prosthetic modelling of implants may benefit from computer-assisted navigation.

Animals↗
PubMed2000

Identification of a novel insertion sequence element in Streptococcus agalactiae. bspeller@imib.rwth-aachen.de.

Gain and loss of bacterial pathogenicity is often associated with mobile genetic elements. A novel insertion sequence (IS) element designated ISSa4 was identified in Streptococcus agalactiae (group B streptococci). The 963bp IS element is flanked by 25bp perfect inverted repeats and led to the duplication of a 9bp target sequence at the insertion site. ISSa4 contains one open reading frame coding for a putative transposase of 287 aa and exhibits closest similarities to insertion elements of the IS982 family which has previously not been identified in streptococci. Analysis of different S. agalactiae strains showed that the copy number of ISSa4 in S. agalactiae varies significantly between strains. The S. agalactiae strain with the highest copy number of ISSa4 was nonhemolytic and harbored one copy inserted in cylB, which encodes the membrane-spanning domain of the putative hemolysin transporter (Spellerberg et al., 1999. Identification of genetic determinants for the hemolytic activity of Streptococcus agalactiae by ISS1 transposition. J. Bacteriol. 181, 3212-3219). Determination of the distribution of ISSa4 in different S. agalactiae strains revealed that ISSa4 could be detected only in strains isolated after 1996, which might indicate a recent acquisition of this novel insertion element by S. agalactiae.

Amino Acid Sequence↗
PubMed2002

The localized expression of extracellular matrix components in healing tendon insertion sites: an in situ hybridization study.

The localized expression of a number of extracellular matrix genes was evaluated over time in a novel rat rotator cuff injury model. The supraspinatus tendons of rats were severed at the bony insertion and repaired surgically. The healing response was evaluated at 1, 2, 4, and 8 weeks post-injury using histologic and in situ hybridization techniques. Expression patterns of collagens (I, II, III, IX, X, XII), proteoglycans (decorin, aggrecan, versican, biglycan, fibromodulin), and other extracellular matrix proteins (elastin, osteocalcin, alkaline phosphatase) were evaluated at the healing tendon to bone insertion site. Histologic results indicate a poor healing response to the injury, with only partial recreation of the insertion site by 8 weeks. In situ hybridization results indicate a specific pattern of genes expressed in each zone of the insertion site (i.e., tendon, fibrocartilage, mineralized cartilage, bone). Overall, expression of collagen types I and XII, aggrecan, and biglycan was increased, while expression of collagen type X and decorin was decreased. Expression of collagen type I, collagen type XII, and biglycan decreased over time, but remained above normal at 8 weeks. Results indicate that the rat supraspinatus tendon is ineffective in recreating the original insertion site, even at 8 weeks post-injury, in the absence of biological or biomechanical enhancements.

Animals↗
PubMed2003

Transbrachial arterial insertion of aortic occlusion balloon catheter in patients with shock from ruptured abdominal aortic aneurysm.

OBJECTIVE: Of 125 surgical patients with abdominal aortic aneurysm (AAA) treated from 1999, 11 patients with deep shock from ruptured AAAs who underwent aortic occlusion balloon catheter (AOBC) insertion before laparotomy were studied. METHODS: With the patients under local anesthesia, the brachial artery was exposed and the balloon catheter was inserted into the thoracic aorta. The balloon was inflated halfway and pulled back gently to the orifice of the left subclavian artery, and was advanced with the aid of blood flow down to the abdominal aorta. After full inflation of the balloon, the catheter was pulled until the balloon was fixed at the proximal shoulder of the AAA. RESULTS: AOBC insertion was completed within 16.1 +/- 5.1 minutes. Systolic blood pressure at presentation was 84.1 +/- 31.7 mm Hg, deteriorated to 60.9 +/- 15.4 mm Hg on arrival in the operating room, and increased significantly (P <.0001) to 123.4 +/- 25.3 mm Hg after AOBC insertion. The balloon burst in three patients. Embolic complications were observed in two patients. There were three deaths, two associated with the balloon bursting. In nine patients whose shock was successfully controlled by AOBC, operative mortality was 11%. CONCLUSION: Transbrachial arterial insertion of an AOBC may be useful to ameliorate hemorrhagic shock in patients with ruptured AAAs.

Aged↗
PubMed1997

Distal insertions of abductor pollicis longus muscle and arthritis of the first carpometacarpal joint in 104 dissections.

The different types of distal insertions of the tendons of the abductor pollicis longus muscle (APL) were studied in 104 cadaveric hands, and the appearance of the rhizarthrosis in the level of the basal joint of the thumb, as well, in a try to detect possible anatomical relationships. From the anatomical point of view, it was evident that the insertions of the APL muscle are usually multiple (95%), that the insertion to the base of the first metacarpal is constantly present, accompanied in 70% of the cases with an insertion to the trapezium. Finally, the accessory tendon to the thenar eminence was proved to be extremely frequent (42%). Rhizarthrosis has been found in 97% of the dissections. The lateral compartment of the joint surface appeared to be the most frequently affected with arthritis (71%) and probably the starting point of the lesion. But no correlation has been recorded between severe arthritis and any type of distal insertion of abductor pollicis longus muscle. Early tenotomy of some tendons, in order to prevent arthritis of the first CMC joint, cannot be recommended from this study.

Arthritis↗
PubMed1999

Sonographic guided insertion of electrodes into the cruciate ligaments of the knee.

The present cadaver study examined the probability of accurate ultrasound guided insertion of electrodes into the anterior (ACL) and posterior (PCL) cruciate ligament with a fine needle. Visualisation of the structures appeared clearest from the posterior approach. From this approach 24 electrodes were inserted into the PCL and six into the ACL. From the anterior 16 were inserted into the ACL and six into the PCL. Twenty-one out of 24 electrodes were placed correctly into the PCL from the posterior view, and four out of six were placed correctly from the anterior view. From the posterior view four out of six were placed correctly in the ACL, and eight electrodes out of 16 were placed correctly from the anterior view. In conclusion, ultrasound guided insertion of electrodes from the posterior view can be performed with high accuracy into the PCL, whereas insertion into the ACL seems to be less accurate, probably because it is more difficult to visualise.

Aged↗
PubMed2001

Effect of tracheal intubation or laryngeal mask airway insertion on intraocular pressure using balanced anesthesia with sevoflurane and remifentanil.

STUDY OBJECTIVES: To study the effect of tracheal intubation or laryngeal mask airway (LMA) insertion on intraocular pressure (IOP) in strabismus patients undergoing balanced anesthesia with sevoflurane and remifentanil. DESIGN: Open, prospective, randomized study. SETTING: Tertiary care academic medical institution. PATIENTS: 40 adult ASA physical status I and II patients scheduled for elective strabismus surgery. INTERVENTION: Patients were randomized to receive either tracheal intubation or LMA insertion following mask induction with sevoflurane in combination with IV remifentanil. MEASUREMENTS: Intraocular pressure, mean arterial pressure (MAP), and heart rate (HR) were measured before induction, immediately following induction, and after airway insertion. MAIN RESULTS: Intraocular pressure after tracheal intubation or LMA insertion did not differ significantly from preoperative baseline values. Mean arterial pressure and HR did not significantly differ between groups at any time point. CONCLUSIONS: Remifentanil and sevoflurane are not associated with an increase in IOP response during tracheal intubation or LMA insertion above baseline in healthy patients undergoing ophthalmic surgery.

Adjuvants, Anesthesia↗
PubMed2002

A PI3-kinase signaling code for insulin-triggered insertion of glucose transporters into the plasma membrane.

Activation of phosphatidyl-inositol-3'-OH-kinase (PI3K) and the resulting production of phosphatidyl-inositol-3,4,5-trisphosphate (PIP3) are ubiquitous signaling steps that link various cell surface receptors to multiple intracellular targets. In fat and muscle cells, the same PI3K pathway that regulates metabolic enzymes, proliferation, and differentiation has also been shown to be involved in insulin-triggered insertion of glucose transporter GLUT4 into the plasma membrane. The multiple PI3K functions raise the question of how the same PI3K pathway can be selectively used for different cell functions. Here we developed a dual-color evanescent wave microscopy method to simultaneously measure PIP3 production and GLUT4 insertion in individual 3T3L1 adipocytes. Activation of PI3K was found to be both necessary and sufficient for triggering GLUT4 insertion, but transporter insertion was markedly suppressed for small-amplitude, persistent PIP3 signals and for large-amplitude, short PIP3 signals. The rejection of these common PI3K signaling responses may explain the selective advantage of insulin over platelet-derived growth factor and other stimuli for inducing GLUT4 insertion. Our study suggests that the same PI3K pathway can control specific cell functions by relying on effector systems that respond to particular receptor-encoded time courses and amplitudes of PIP3 signals.

Cell Membrane↗