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Antibiotic prophylaxis for intrauterine contraceptive device insertion.

BACKGROUND: Concern about the risk of upper genital tract infection (pelvic inflammatory disease) often limits use of the IUD, a highly effective contraceptive. Prophylactic antibiotic administration around the time of induced abortion significantly reduces the risk of postoperative endometritis.(Sawaya, 1996) Since the risk of IUD-related infection is limited to the first few weeks to months after insertion,(Lee, 1983; Farley, 1992) contamination of the endometrial cavity at the time of insertion(Mishell, 1966) appears to be the mechanism, rather than the IUD or string itself. Thus, antibiotic administration before IUD insertion might reduce the risk of upper genital tract infection from passive introduction of bacteria at insertion. OBJECTIVES: To assess the effectiveness of prophylactic antibiotic administration before IUD insertion in reducing IUD-related complications and discontinuations within three months of insertion. The primary outcome was pelvic inflammatory disease (four reports) or early removals of the device (two reports). SEARCH STRATEGY: We searched both MEDLINE and EMBASE, handsearches of journals through CENTRAL, and lists of references. We also wrote to international experts in the field to identify unpublished studies. SELECTION CRITERIA: We included randomized controlled trials using any antibiotic compared with a placebo. We found four such trials; two had pilot study data available. DATA COLLECTION AND ANALYSIS DATA EXTRACTION: We used searches of MEDLINE, EMBASE, and handsearches of journals available through CENTRAL. We also reviewed lists of references in original research and in review articles. We wrote to experts to identify unpublished trials and made telephone calls to authors to supply missing information. Two independent reviewers abstracted data. We assessed the validity of each study using methods suggested in the Cochrane Handbook. DATA SYNTHESIS: We generated 2x2 tables for the principal outcome measures. We used the Peto modified Mantel-Haenszel technique to calculate odds ratios and assessed statistical heterogeneity between studies. MAIN RESULTS: The odds ratios for pelvic inflammatory disease associated with use of prophylactic doxycycline or azithromycin compared with placebo or no treatment was 0.89 (95%CI 0.53-1.51). Use of prophylaxis was associated with a small reduction in unscheduled vists to the provider (OR 0.82; 95% CI 0.70-0.98). Use of doxycycline or azithromycin had little effect on the likelihood of removal of the IUD within 90 days of insertion (OR 1.05; 95% CI 0.68-1.63). Significant heterogeneity did not exist between studies. REVIEWER'S CONCLUSIONS: Use of either doxycycline 200 mg or azithromycin 500 mg by mouth before IUD insertion confers little benefit. While the reduction in unscheduled visits to the provider was marginally significant, the cost-effectiveness of routine prophylaxis remains questionable. A uniform finding in these trials was the low risk of IUD-associated infection, with or without use of antibiotic prophylaxis.

Antibiotic Prophylaxis↗

The nature of the monomer insertion step in the allylnickel(II)-catalyzed 1,4-polymerization of 1,3-butadiene: sigma-allyl-insertion mechanism versus pi-allyl-insertion mechanism.

We present a theoretical investigation on the nature of the monomer insertion step in the allylnickel(II)-catalyzed 1,4-polymerization of 1,3-butadiene that employed a gradient-corrected DFT method. We have explored critical elementary steps of the whole polymerization cycle for the trans-1,4 regulating cationic allylnickel(II) [RC3H4NiII(C4H6)L]+ catalyst. These steps are i) cis-butadiene insertion into either the eta 1-sigma-butenyl-NiII bond (sigma-allyl insertion mechanism) or the eta 3-pi-butenyl-NiII bond (pi-allyl insertion mechanism) along with competing pathways for generation of trans-1,4 and cis-1,4 polymer units, and ii) anti-syn isomerization. Based on the analysis of geometric and electronic structures of key species involved and the energetics, we present a detailed insight into the different nature of the monomer insertion step according to the two mechanistic alternatives. An understanding of why the pi-allyl insertion mechanism is favored over the sigma-allyl insertion mechanism is provided. eta 1-sigma-butenyl-NiII Species are predicted to be sparsely populated and also distinctly less reactive than eta 3-pi-butenyl-NiII species. Although they are commonly believed to be reactive intermediates, eta 1-sigma-butenyl-NiII species are, therefore, not likely to be involved along viable pathways for cis-butadiene insertion into the butenyl-NiII bond. The present investigation corroborates our previous conclusion that the pi-allyl insertion mechanism represents the preferred mechanism for the monomer insertion step in the allylnickel(II)-catalyzed 1,4-polymerization of 1,3-butadiene. On the other hand, the suggested alternative sigma-allyl insertion mechanism has to be considered to be not operative, for both thermodynamic and kinetic reasons. Furthermore, the sigma-allyl insertion mechanism would neither provide a rationalization of cis-trans selectivity nor of chemoselectivity in the allylnickel(II)-catalyzed 1,4-polymerization of 1,3-butadiene.

Journal Article↗

Behavior of diphtheria toxin T domain containing substitutions that block normal membrane insertion at Pro345 and Leu307: control of deep membrane insertion and coupling between deep insertion of hydrophobic subdomains.

Diphtheria toxin T domain aids the translocation of toxin A chain across membranes. T domain has two hydrophobic layers/subdomains that can insert deeply into membranes: helices TH8 and 9, which form a transmembrane hairpin, and helices TH5-7, which form a nonclassical, nontransmembrane structure. Substitutions were made at Pro345, a residue located near the turn between TH8 and 9. P345 is critical for toxicity and pore formation by the T domain. Fluorescence methods showed that hairpin-disrupting Gly or Glu substitutions at 345 did not insert into lipid bilayers as deeply as the wild-type protein, and consistent with previous studies, these mutations reduced pore formation activity as assayed by a novel biotin-streptavidin-based influx assay. Introducing Pro at positions 347 or 353 not only failed to compensate for substitutions at P345, but also they further disrupted deep insertion and/or pore formation. Substitution of P345 with Asn, a residue that promotes helical hairpin formation almost as well as Pro, resulted in somewhat more normal insertion and pore formation than other substitutions. Importantly, a P345E substitution disrupted deep insertion of TH5-7. This suggests that TH8 and 9 and TH5-7 undergo some sort of coordinated insertion into the lipid bilayer and/or that the membrane-inserted T domain has a distinct tertiary structure in which TH5-7 interact with TH8 and 9 instead of consisting of noninteracting hydrophobic segments. Intriguingly, a L307R substitution in TH6, which disrupted deep insertion of TH7, had only a weak effect on pore formation and deep insertion of TH8 and 9. This suggests that the TH8 and 9 region can insert independently of TH5-7 to some degree and that TH8 and 9 insertion may occur early in T-domain insertion.

Amino Acid Substitution↗

Immediate post-abortal insertion of intrauterine devices.

OBJECTIVES: To assess the safety and efficacy of IUD insertion immediately after spontaneous or induced abortion. SEARCH STRATEGY: We used Medline, Popline, and EMBASE computer searches, supplemented by review articles and contacts with investigators. SELECTION CRITERIA: We sought all randomized controlled trials that had at least one treatment arm that involved IUD insertion immediately after an induced abortion or after curettage for spontaneous abortion. We identified 12 trials which described random assignment but excluded three from this review. Two of these revealed unethical research conduct, and one used alternate assignment to treatments. DATA COLLECTION AND ANALYSIS: We evaluated the methodological quality of each report and abstracted information onto a data collection form. We focused on gross discontinuation rates (single-decrement life table analysis) for accidental pregnancy, perforation, expulsion, and pelvic inflammatory disease. We entered the data into RevMan 3.1 for analysis of Peto odds ratios. MAIN RESULTS: In large multicenter trials, the TCu 220C device proved superior to either the Lippes Loop D or the Copper 7 IUDs for immediate post-abortal insertion. The Peto OR for discontinuation for pregnancy was 0.4 (95% CI 0.2-0.7) compared with the Lippes Loop D and 0.5 (95% CI 0.3-0.8) compared with the Copper 7. Expulsions were also significantly less common with the TCu 220C than with the other two IUDs. In single-center trials, the Nova T IUD had a signicantly higher discontinuation rate for pregnancy than did the Multiload 250 (OR 4.5; 95% CI 1.0-19.8), while the Nova T had a significantly lower discontinuation rate for pregnancy than did the TCu 200 (OR 0.3; 95% CI 0.1-0.9). Only one trial compared immediate vs. delayed insertion. In this trial, the performance of the Copper 7 IUD inserted immediately after abortion was inferior to that after interval insertion (remote from pregnancy), although the differences were not statistically significant. Addition of copper sleeves to a Lippes Loop D improved its performance, but addition of a topical hydrogel to a Spring Coil did not offer benefit. Overall, rates of perforation and pelvic inflammatory disease were low. REVIEWER'S CONCLUSIONS: Insertion of an IUD immediately after abortion is both safe and practical. This was true for both induced and reported "spontaneous" abortions, many of which may have been induced under clandestine circumstances. IUD expulsion rates were higher after second-trimester abortions than after earlier abortions, so delaying insertion may be advisable after later abortions. Although Copper 7 devices inserted unrelated to pregnancy may perform better than those inserted after abortion, many women who express interest in intrauterine contraception do not return for the scheduled insertion. These women may remain unprotected against unintended pregnancy. However, evidence is inadequate to compare the safety and efficacy of IUD insertion immediately after abortion vs. insertion some weeks later.

Abortion, Induced↗

Immediate post-partum insertion of intrauterine devices.

OBJECTIVES: To assess the efficacy and feasibility of IUD insertion immediately after expulsion of the placenta. Our a priori hypothesis was that this practice is safe but associated with higher expulsion rates than interval IUD insertion. SEARCH STRATEGY: We used MEDLINE, Popline, EMBASE, and Cochrane Controlled Trials Register computer searches, supplemented by review articles and contact with investigators. SELECTION CRITERIA: We sought all randomized controlled trials that had at least one treatment arm that involved immediate post-partum (within ten minutes of placental expulsion) insertion of an IUD. Comparisons could include different IUDs, different insertion techniques, immediate vs. delayed post-partum insertion, or immediate vs. interval insertion (unrelated to pregnancy). Studies could include either vaginal or cesarean deliveries. DATA COLLECTION AND ANALYSIS: We evaluated the methodological quality of each report and sought to identify duplicate reporting of data from multicenter trials. We abstracted data onto data collection forms. Principal outcome measures included pregnancy, expulsion, and continuation rates. Because the trials did not have uniform interventions, we were unable to aggregate them in a meta-analysis. MAIN RESULTS: We found no randomized controlled trials that directly compared immediate post-partum insertion with either delayed post-partum or interval insertion. Modifications of existing devices, such as adding absorbable sutures or additional appendages, did not appear beneficial. Most studies showed no important differences between insertions done by hand or by instruments. Lippes Loops and Progestasert devices did not perform as well as did copper devices. REVIEWER'S CONCLUSIONS: Immediate post-partum insertion of IUDs appeared safe and effective, though direct comparisons with other insertion times were lacking. Advantages of immediate post-partum insertion include high motivation, assurance that the woman is not pregnant, and convenience. However, expulsion rates appear to be higher than with interval insertion. The popularity of immediate post-partum IUD insertion in countries as diverse as China, Mexico, and Egypt support the feasibility of this approach. Early follow-up may be important in identifying spontaneous IUD expulsions.

Feasibility Studies↗

Variables influencing intravenous catheter insertion difficulty and failure: an analysis of 339 intravenous catheter insertions.

BACKGROUND: Inserting an intravenous catheter (IV) is one of the most frequently performed invasive procedures by nurses. Little research has been conducted on ways to reduce the difficulty and failure, and enhance the ease and success, of IV insertion. We conducted this study to determine variables associated with IV insertion difficulty, failure, and success, and to learn special techniques nurses use to facilitate IV insertion. METHODS: Data were collected on 339 IV insertions in hospitalized patients by 34 registered nurses. The data included information about the nurse (eg, age, education, and self-rated IV insertion skill); the patient (eg, age and race); the IV (eg, site, gauge, and type); and the IV insertion, (eg, duration and difficulty). Data were analyzed to determine the effects of these variables on IV insertion outcome. In addition, nurses were asked to describe special techniques they used to facilitate IV insertion. RESULTS: A total of 77% of the IV insertions were successful. Nurses who were older, had more years of experience, were certified in a specialty, and rated themselves higher in insertion skill had significantly more successful insertions than their younger and less-experienced and less-skilled counterparts (P < .001). Successful IV insertions were significantly faster (mean 32 seconds) than unsuccessful ones (mean 66 seconds) (P < .001), and were rated as significantly less difficult (P < .001). Failed IV insertions were associated with higher degrees of difficulty arising from vein variables, such as vein rolled or vein was resistant to puncture, and patient variables, such as tough or dark skin and patient movement. The nurses described a wide variety of techniques to facilitate insertion success. The most frequently mentioned were getting self and patient in a comfortable position, using mechanical stimulation such as tapping the vein, and stabilizing the vein. CONCLUSION: Approximately one fourth of the 339 IV insertions in this study were unsuccessful. Repeated insertion attempts are painful and costly. This study identified nurse, patient, and IV variables associated with IV insertion success and failure. Future research is needed to confirm and expand these findings and to develop interventions to improve IV insertion skills and outcomes.

Adult↗

Evaluation of the advance off-stylet insertion technique and the cochlear insertion tool in temporal bones.

OBJECTIVE: The concept and design of new cochlear implant electrodes is a challenging process. To evaluate new electrode designs, we present a study that uses a microgrinding procedure to evaluate damage to the microstructures of the cochlea resulting from the insertion procedure. In this study, we compared different insertion techniques with the Contour electrode with Softip for placement inside the cochlea and any resulting damage. METHODS: Twenty-five fresh frozen human temporal bones were used to compare electrode insertion characteristics with three insertion techniques (i.e., conventional insertion, Advance Off-Stylet performed manually, and Advance Off-Stylet performed with insertion tool) and two prototype variants of the Contour electrode with Softip (referred as Softip I and Softip II in this article). Five temporal bones were used for each arm of the study: Softip I electrode and conventional insertion; Softip I electrode and manual Advance Off-Stylet insertion; Softip I electrode and Advance Off-Stylet insertion with an early experimental insertion tool; Softip II prototype electrode and manual Advance Off-Stylet insertion; and Softip II prototype and Advance Off-Stylet insertion with a prototype insertion tool. The temporal bones were dehydrated and embedded in epoxy and used for the microgrinding procedure. Resulting images were documented and compared with conventional radiographic images. RESULTS: Our results showed that, especially when using the conventional insertion technique with Softip I electrode arrays, basilar membrane perforations were observable. Using the prototype insertion tool, good placement of the electrode array but also two basilar membrane perforations (one with each type of electrode) were observed. In contrast, the Advance Off-Stylet insertion technique did not show basilar membrane perforation with Softip I and II electrodes and resulted in reliable perimodiolar placement of the arrays. CONCLUSION: Using microgrinding of temporal bones, the Advance Off-Stylet insertion technique was proven to enable more atraumatic insertions of Contour electrodes with Softip and to provide very reliable perimodiolar placements.

Basilar Membrane↗

Structures of ubiquitin insertion mutants support site-specific reflex response to insertions hypothesis.

We previously concluded that, judging from NMR chemical shifts, the effects of insertions into ubiquitin on its conformation appear to depend primarily on the site of insertion rather than the sequence of the insertion. To obtain a more complete and atomic-resolution understanding of how these insertions modulate the conformation of ubiquitin, we have solved the crystal structures of four insertional mutants of ubiquitin. Insertions between residues 9 and 10 of ubiquitin are minimally perturbing to the remainder of the protein, while larger alterations occur when the insertion is between residues 35 and 36. Further, the alterations in response to insertions are very similar for each mutant at a given site. Two insertions, one at each site, were designed from structurally homologous proteins. Interestingly, the secondary structure within these five to seven amino acid residue insertions is conserved in the new protein. Overall, the crystal structures support the previous conclusion that the conformational effects of these insertions are determined largely by the site of insertion and only secondarily by the sequence of the insert.

Crystallography, X-Ray↗

Intradermal normal saline solution, self-selected music, and insertion difficulty effects on intravenous insertion pain.

OBJECTIVE: To examine the effect of listening to self-selected music versus an intradermal injection of normal saline solution on the intensity and distress of intravenous (IV) catheter insertion pain. DESIGN: Prospective, randomized, controlled study. SETTING: Inpatient and outpatient units in 2 university-affiliated southwestern medical centers. PATIENTS: One hundred ten adult inpatients and outpatients undergoing IV therapy. OUTCOME MEASURES: Pain intensity, pain distress, and IV insertion difficulty visual analog scales. INTERVENTION: Patients were randomly assigned to receive an intradermal injection of normal saline solution, listen with headphones to self-selected music, or be in a control group for IV insertion. RESULTS: A MANOVA revealed no statistically significant multivariate or univariate differences in pain by treatment group, but significantly higher pain distress scores with failed IV insertions. The pain intensity and distress scores were significantly higher in the saline solution group when compared with the music and control groups combined. Insertion difficulty was significantly positively correlated with pain intensity and distress for the entire sample, with weak, nonsignificant correlations in the music group. CONCLUSION: Intradermal unpreserved saline solution contributes to greater pain intensity and distress, greater insertion difficulty, and a higher failure rate than the use of music or routine IV insertion. Listening to preferred music attenuates the effect of insertion difficulty on IV insertion pain. Intravenous insertion attempts were unsuccessful in more than one third of the subjects, resulting in higher pain distress scores. Further research is needed on interventions to reduce IV insertion pain and on factors contributing to IV insertion failure.

Adult↗

Effects of insertion conditions on tissue strain and vascular damage during neuroprosthetic device insertion.

Long-term integration of neuroprosthetic devices is challenged by reactive responses that compromise the brain-device interface. The contribution of physical insertion parameters to immediate damage is not well described. We have developed an ex vivo preparation to capture real-time images of tissue deformation during device insertion using thick tissue slices from rat brains prepared with fluorescently labeled vasculature. Qualitative and quantitative assessments of damage were made for insertions using devices with different tip shapes inserted at different speeds. Direct damage to the vasculature included severing, rupturing and dragging, and was often observed several hundred micrometers from the insertion site. Slower insertions generally resulted in more vascular damage. Cortical surface features greatly affected insertion success; insertions attempted through pial blood vessels resulted in severe tissue compression. Automated image analysis techniques were developed to quantify tissue deformation and calculate mean effective strain. Quantitative measures demonstrated that, within the range of experimental conditions studied, faster insertion of sharp devices resulted in lower mean effective strain. Variability within each insertion condition indicates that multiple biological factors may influence insertion success. Multiple biological factors may contribute to tissue distortion, thus a wide variability was observed among insertions made under the same conditions.

Animals↗

Insertional polymorphism and antiquity of PDR1 retrotransposon insertions in pisum species.

Sequences flanking 73 insertions of the retrotransposon PDR1 have been characterized, together with an additional 270 flanking regions from one side alone, from a diverse collection of Pisum germ plasm. Most of the identified flanking sequences are repetitious DNAs but more than expected (7%) lie within nuclear gene protein-coding regions. The approximate age of 52 of the PDR1 insertions has been determined by measuring sequence divergence among LTR pairs. These data show that PDR1 transpositions occurred within the last 5 MY, with a peak at 1-2.5 MYA. The insertional polymorphism of 68 insertions has been assessed across 47 selected Pisum accessions, representing the diversity of the genus. None of the insertions are fixed, showing that PDR1 insertions can persist in a polymorphic state for millions of years in Pisum. The insertional polymorphism data have been compared with the age estimations to ask what rules control the proliferation of PDR1 insertions in Pisum. Relatively recent insertions (< approximately 1.5 MYA) tend to be found in small subsets of the Pisum accessions set, "middle-aged" insertions (between approximately 1.5 and 2.5 MYA) vary greatly in their occurrence, and older insertions (> approximately 2.5 MYA) are mostly found in small subsets of Pisum. Finally, the average age estimate for PDR1 insertions, together with an existing data set for PDR1 retrotransposon SSAP markers, has been used to derive an estimate of the effective population size for Pisum of approximately 7.5 x 10(5).

Base Sequence↗

Sustained activation of Erk1/2 MAPK and cell growth suppression by the insert-negative, but not the insert-positive isoform of the human calcitonin receptor.

Recently we reported that calcitonin (CT) induces growth arrest at the G2 stage of the cell cycle in HEK-293 cell lines expressing the most abundant, insert-negative, isoform of the human CT receptor (insert -ve hCTR). The present study investigates the involvement of the MAPK signalling pathway in the anti-proliferative actions of CT and compares the activity of an isoform of the hCTR that contains a 16 amino acid insert in the first putative intracellular loop (insert +ve hCTR). Comparison of HEK-293 cells stably transfected with the insert -ve or the insert +ve hCTR, showed that accumulation of cAMP and intracellular free calcium in response to CT were specific for the insert -ve receptor isoform. However, a novel acidification of the extracellular medium was mediated by both isoforms. Treatment with CT of cells expressing the insert -ve hCTR, caused a decrease in cell growth associated with an induction of p21(WAF1/CIP1). Analysis by fluorescence-activated cell scanning showed that growth inhibition was associated with an accumulation of cells in G2. CT treatment of cells expressing the insert -ve, but not insert +ve hCTR, induced the phosphorylation of Erk1/2 MAPK, which persisted for at least 72 h. Treatment of cells expressing the insert -ve hCTR with the MAPK kinase (MEK) inhibitor, PD-98059, inhibited the phosphorylation of Erk1/2 and abrogated the growth inhibitory effects of salmon CT, the accumulation of cells in G2, and the associated induction of p21(WAF1/CIP1). These data suggest that activation of Erk1/2 are downstream effectors of the insert -ve hCTR in modulating cell cycle progression.

Binding, Competitive↗

Characterization of pre-insertion loci of de novo L1 insertions.

The human Long Interspersed Element-1 (LINE-1) and the Short Interspersed Element (SINE) Alu comprise 28% of the human genome. They share the same L1-encoded endonuclease for insertion, which recognizes an A+T-rich sequence. Under a simple model of insertion distribution, this nucleotide preference would lead to the prediction that the populations of both elements would be biased towards A+T-rich regions. Genomic L1 elements do show an A+T-rich bias. In contrast, Alu is biased towards G+C-rich regions when compared to the genome average. Several analyses have demonstrated that relatively recent insertions of both elements show less G+C content bias relative to older elements. We have analyzed the repetitive element and G+C composition of more than 100 pre-insertion loci derived from de novo L1 insertions in cultured human cancer cells, which should represent an evolutionarily unbiased set of insertions. An A+T-rich bias is observed in the 50 bp flanking the endonuclease target site, consistent with the known target site for the L1 endonuclease. The L1, Alu, and G+C content of 20 kb of the de novo pre-insertion loci shows a different set of biases than that observed for fixed L1s in the human genome. In contrast to the insertion sites of genomic L1s, the de novo L1 pre-insertion loci are relatively L1-poor, Alu-rich and G+C neutral. Finally, a statistically significant cluster of de novo L1 insertions was localized in the vicinity of the c-myc gene. These results suggest that the initial insertion preference of L1, while A+T-rich in the initial vicinity of the break site, can be influenced by the broader content of the flanking genomic region and have implications for understanding the dynamics of L1 and Alu distributions in the human genome.

Alu Elements↗

Insertion torque profile during pedicle screw insertion of the thoracic spine with and without violation of the pedicle wall: comparison between cylindrical and conical designs.

STUDY DESIGN: Biomechanical study in human cadaveric thoracic spines. OBJECTIVE: To compare the insertion torque profile of cylindrical and conical screws with normal insertion tract, and with violation of the pedicle. SUMMARY OF BACKGROUND DATA: Previous studies revealed higher insertion torque for conical screws. No study has investigated the torque profile of both screws when there is violation of the pedicle. METHODS: The pedicle screws were inserted intrapedicularly (Type 1), violating the lateral cortex of the pedicle (Type 2), and violating the medial cortex of the pedicle (Type 3). Type 2 screws were further subdivided into those having contact with the lateral vertebral body (2a) and those without (2b). Type 3 screws were subdivided into those having contact with the medial pedicle wall (3a) and without (3b). RESULTS.: During initial insertion, the torque increased as they penetrated into the pedicles. With violation of the lateral cortex of the pedicle, insertion torque for the cylindrical screw decreased as the screw advanced anteriorly out of the pedicle. The insertion torque for the conical screw continued to increase at a constant rate after violation of the lateral cortex. With medial breach of the pedicle wall, torque profile of the conical screws remained the same as those inserted in the normal trajectory. There was a decline in the insertion torque for the cylindrical screws when medial violation of the pedicle wall occurred, the decrease being greater for Type 3b as compared with Type 3a screws. CONCLUSIONS: Surgeons may be unable to perceive the occurrence of medial or lateral breach of the cortex when inserting a conical screw. Surgeons inserting cylindrical screws with Type 3a violation may not be able to perceive a significant decrease in torque.

Bone Screws↗

Evaluation of a unique, nurse-inserted, peripherally inserted central catheter program.

BACKGROUND: Concerns regarding the safety and success of peripherally inserted central catheters (PICCs) placed at the bedside in the pediatric population initially precluded the development of a nurse-inserted PICC program at our pediatric center. Previously, all PICCs were inserted by interventional radiologists (IRs) with fluoroscopic guidance. A new nurse-inserted PICC program was initiated with collaboration between PICC nurses and IRs. METHODS: Three nurses participated in the project. Patients who met preestablished selection criteria were approached. All insertions were performed with sterile technique on the fluoroscopy table, with IRs available to support the PICC nurse. Veins were accessed visually or through palpation. Final tip position was confirmed in all cases with contrast material administration and fluoroscopy. Additional fluoroscopy was performed only if placement difficulties were encountered. All patients were monitored prospectively. RESULTS: Ninety-nine patients (age: 3-18 years; average age: 13.6 years) met the selection criteria. Two patients underwent primary insertion by an IR. The remaining 97 patients underwent an insertion attempt by a nurse. Sixty-nine PICCs (71.1%) were placed successfully by a nurse, 15 (15.5%) required minor assistance from an IR, and 13 (13.4%) were inserted by an IR after an unsuccessful nurse attempt. No insertion complications were noted. Insertion difficulties included difficulty advancing the catheter (19.6%), difficulty cannulating the vein (6.2%), and tip malposition (2.1%). Postinsertion complications occurred for 27.8% of PICCs, and 13.4% required removal before the end of therapy. CONCLUSION: This novel, pediatric nurse-inserted PICC program has a good safety profile, high success rate, and low postprocedural complication rate.

Adolescent↗

Oral insertion of a flexible bronchoscope is associated with less discomfort than nasal insertion for Korean patients.

OBJECTIVE: The route of bronchoscope insertion varies between centres, without a firm rationale based on well-designed studies. We therefore compared nasal and oral insertion of a flexible bronchoscope and evaluated efficacy and patient satisfaction. DESIGN: Prospective randomised study of patients who underwent flexible bronchoscopy from May to September 2003 and who were randomly assigned to nasal and oral insertion approaches. RESULTS: Clinical characteristics, factors related to the procedure and patient satisfaction were analysed. In total, 307 patients were randomly assigned to the nasal (n = 158) or oral insertion groups (n = 149). No difference in baseline characteristics was identified between the groups. Insertion by the oral route was associated with a smaller amount of lidocaine use during the procedure (P = 0.04) and less frequent insertion site bleeding (P = 0.005). Patients assigned to oral insertion reported less discomfort during anaesthesia (P = 0.01) and scope insertion (P < 0.001), as well as less dyspnoea (P = 0.04) and coughing (P = 0.03). CONCLUSION: Oral insertion of a flexible bronchoscope was associated with less discomfort for patients than nasal insertion, although the route of insertion had no significant effect on outcome.

Adult↗

Viral sequence insertions and a novel cellular insertion in the NS2 gene of cytopathic isolates of bovine viral diarrhea virus as potential cytopathogenicity markers.

Cytopathogenicity of bovine viral diarrhea virus (BVDV) has been shown to correlate with the presence of insertions of cellular sequences, duplication of viral sequences with or without insertions, deletions, and point mutations in the genomes of cytopathogenic (cp) strains. In the present study we have investigated cytopathogenicity markers in the genomes of six cp BVDV isolates. The viruses were selected as representatives of various forms of BVDV infection, in some cases presumably induced by vaccination with a live attenuated vaccine. The complete NS2-3 coding region of the six isolates and of the vaccine virus were amplified by reverse transcription-polymerase chain reaction (RT-PCR) and sequenced. In the genomes of four isolates (H6379, H6712, H8427 and H-BVD MD) and of the vaccine virus, a 45-nucleotide viral insertion was found at nucleotide position 4355, encompassing nucleotides 8402-8446, that encode 15 amino acids of the NS4B/NS5A junction region in a normal BVDV genome. Isolate H3887 had a 21-nucleotide insertion of non-viral origin, also located at nucleotide position 4355. This insertion has a high homology with a gene coding for murine interferon-induced guanylate-binding protein 1, and represents the first non-viral insertion identified at this position of the NS2 coding region. Isolate H3142 carries a 42-nucleotide insertion at position 4361, identical to a part of the NS5B gene mapping to position 11078-11119. Additionally, this isolate also has a deletion of three nucleotides (positions 4448-4450). The role of the 45-nucleotide insertion in expression of NS3 was investigated using the vaccine virus. The NS2-3 gene of this virus, and that of a generated insertion-negative variant were cloned in the mammalian expression vector pCI, and expressed in bovine turbinate cells. Western blot analysis revealed that the insertion contributed to a partial cleavage of NS2-3 generating NS3, the marker protein for cytopathogenicity in BVDV. The genome rearrangements found in these isolates occurred preferentially at position 4355, suggesting that this part of the genome could represent a potential hot spot for recombination events in ncp BVDV. The molecular mechanism underlying this phenomenon, however, remains to be elucidated.

Amino Acid Sequence↗

Reengineering of a commercially available bovine intravaginal insert (CIDR insert) containing progesterone.

The purpose of this study was to reengineer a commercially available intravaginal insert containing 1.9 g progesterone (CIDR intravaginal insert) for a 7-day insertion period in cattle. The reengineering process resulted in a reduced initial drug load (1.38 g) and a reduction in the residual drug load following insertion, while at the same time maintaining the biological performance of the insert. The in vitro and in vivo pharmaceutical properties of the commercially available CIDR intravaginal insert were characterized initially to gain a thorough understanding of the factors that affected progesterone release from the insert. The effect of changing a selection of formulation and physical variables of the insert was also investigated (including surface area, drug load, addition of pore forming materials, silicone shore hardness and drug particle size). The knowledge gained from these studies was used to define the characteristics of the reengineered insert which was then manufactured and shown to be bioequivalent and clinically equivalent to the commercially available insert.

Administration, Intravaginal↗