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Stapled versus hand-sewn intestinal anastomosis in pediatric surgery: A systematic review and meta-analysis.

BACKGROUND: Intestinal anastomosis is a core procedure in pediatric gastrointestinal surgery, performed for conditions such as necrotizing enterocolitis, intestinal atresia, Hirschsprung's disease, and inflammatory bowel disease. Although stapled anastomosis (SA) may improve operative efficiency, its safety and effectiveness compared with hand-sewn anastomosis (HA) in children remain uncertain. This meta-analysis compared clinical outcomes of SA and HA in pediatric patients. METHODS: The study followed PRISMA guidelines and was prospectively registered in PROSPERO (CRD420251177257). A systematic search of PubMed, Dimensions, and the Cochrane Library was conducted through June 2025. Studies including children under 7 years undergoing intestinal SA or HA were eligible. Two reviewers independently performed study selection, data extraction, and risk-of-bias assessment using ROB 2 and ROBINS-I tools. Statistical analysis was conducted using Comprehensive Meta-Analysis software (v3) with a random-effects model. RESULTS: Eleven studies involving 903 patients met inclusion criteria, including two randomized controlled trials. Of these, 333 patients underwent SA and 570 underwent HA. SA was associated with significantly shorter operative time (mean difference [MD] = -19.26 min; 95% CI: -24.24 to -14.28; p < 0.001) and earlier initiation of oral feeding (MD = -2.32 days; 95% CI: -3.78 to -0.86; p = 0.002). No significant differences were found in anastomotic leakage, stricture formation, reoperation rate, or length of hospital stay. CONCLUSIONS: Stapled anastomosis appears as safe as hand-sewn techniques in pediatric intestinal surgery while offering shorter operative duration and faster postoperative feeding recovery. Selective use of stapled techniques is supported when anatomically feasible, though further multicenter randomized trials are needed.

Humans↗

Gastrin-releasing peptide in normal and neoplastic human lung: measurement and biochemical characterization.

Levels of gastrin-releasing peptide (GRP) were determined by radioimmunoassay in human normal main and lobar bronchus and parenchymal lung tissue extracts. It was found that the level of GRP differed significantly between all 3 areas. The concentration of GRP was statistically higher in main bronchus (median 6.74 ng/g) compared to both lobar bronchus (median 4.79 ng/g) and parenchymal lung (median 1.73 ng/g), and also statistically higher in lobar bronchus compared to parenchymal lung. Chromatographically, GRP-immunoreactivity in both main and lobar bronchial extracts corresponded to GRP1-27 and GRP18-27, while in lung tissue only one major species was identified which corresponded in retention time to GRP18-27. No significant difference was detected when the levels of GRP in normal lobar bronchus and normal lung tissue were compared to the levels in lobar bronchus and lung taken from patients with lung carcinoma, at a site adjacent to the carcinoma. However, a significant difference was observed between the GRP content of normal main bronchus compared to main bronchus from patients with carcinoma. GRP was measured in 26/56 lung carcinomas examined. The levels ranged from 42,000 ng/g in a carcinoid tumour to 0.18 ng/g in a squamous-cell carcinoma, though only in 6 tumours were the levels outside the range determined for normal pulmonary tissue. Chromatography of selected tumour extracts of different histopathologies showed that there were differences in the GRP products present.

Adenocarcinoma↗

Extraction of features from ultrasound acoustic emissions: a tool to assess the hydraulic vulnerability of Norway spruce trunkwood?

The aim of this study was to assess the hydraulic vulnerability of Norway spruce (Picea abies) trunkwood by extraction of selected features of acoustic emissions (AEs) detected during dehydration of standard size samples. The hydraulic method was used as the reference method to assess the hydraulic vulnerability of trunkwood of different cambial ages. Vulnerability curves were constructed by plotting the percentage loss of conductivity vs an overpressure of compressed air. Differences in hydraulic vulnerability were very pronounced between juvenile and mature wood samples; therefore, useful AE features, such as peak amplitude, duration and relative energy, could be filtered out. The AE rates of signals clustered by amplitude and duration ranges and the AE energies differed greatly between juvenile and mature wood at identical relative water losses. Vulnerability curves could be constructed by relating the cumulated amount of relative AE energy to the relative loss of water and to xylem tension. AE testing in combination with feature extraction offers a readily automated and easy to use alternative to the hydraulic method.

Botany↗

Robotic surgery for gastric gastrointestinal stromal tumors: a systematic review.

Robotic surgery is used for selected gastric gastrointestinal stromal tumours (GISTs), particularly when location makes conventional wedge resection difficult. We synthesised technical, perioperative, pathological, functional and oncological outcomes. PubMed/MEDLINE, Scopus and the Cochrane Library were searched from inception to 14 August 2026. Primary reports with at least three eligible robotic gastric-GIST patients were included. Two reviewers independently selected studies, extracted data and completed design-specific JBI appraisal. Because outcome definitions, denominators and reporting were heterogeneous, findings were synthesised narratively in accordance with SWiM guidance rather than pooled. Twenty-three studies, including six comparative cohorts, were included. Institutional robotic cohorts contained 3-45 eligible patients; one national registry included 1,567 robotic cases. Tumour size ranged from 2.68&#x2009;&#xb1;&#x2009;1.55 to 7.9&#x2009;&#xb1;&#x2009;1.8&#xa0;cm among studies reporting means. Most institutional reports described R0 resection in all eligible patients; exceptions were 23/24 and 24/25, while the registry reported 1,425/1,567 R0 resections. Grade III morbidity occurred in 2/25 patients in one function-preserving series. Registry 30- and 90-day mortality after robotic resection were 0.5% and 0.8%, respectively. Comparative studies did not demonstrate superior postoperative or oncological outcomes with robotic surgery. Robotic gastric-GIST resection appears feasible in selected patients and may facilitate organ-preserving surgery at anatomically challenging sites. Current observational evidence does not establish comparative functional, oncological or economic superiority.

Humans↗

Does this patient have an instability of the shoulder or a labrum lesion?

CONTEXT: History taking and clinical tests are commonly used to diagnose shoulder pain. Unclear is whether tests and history accurately diagnose instability or intra-articular pathology (IAP). OBJECTIVE: To analyze the accuracy of clinical tests and history taking for shoulder instability or IAP. DATA SOURCES: Relevant studies identified through PubMed, EMBASE, CINAHL, and bibliographies of known primary and review articles. STUDY SELECTION: Studies comparing the performance of history items or physical examination with a reference standard were included. Studies on fibromyalgia, fractures, or systemic disorders were excluded. Of 1449 articles, 35 were eligible, and 17 were selected. DATA EXTRACTION: Data were extracted on study population, clinical tests, reference tests, and outcome. The studies' methodological quality (patient spectrum, verification, blinding, and replication) was assessed with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. DATA SYNTHESIS: Six tests showed positive likelihood ratios (LRs) and confidence intervals (CIs). Tests favoring the diagnosis for establishing instability included: relocation (LR, 6.5; 95% CI, 3.0-14.0) and anterior release (LR, 8.3; 95% CI, 3.6-19). Tests showing promise for establishing labral lesions included: the biceps load I and II (LR, 29; 95% CI, 7.3-115.0 and LR, 26; 95% CI, 8.6-80.0), respectively, pain provocation of Mimori (LR, 7.2; 95% CI, 1.6-32.0), and internal rotation resistance strength (LR, 25; 95% CI, 8.1-76.0). The apprehension, clunk, release, load and shift, and sulcus sign tests proved less useful. Results should be cautiously interpreted because studies were completed in select populations in orthopedic practice, mostly assessed by the test designers, and evaluated in single studies only. No accuracy studies were found for history taking or for clinical tests in primary care. CONCLUSIONS: Shoulder complaints are frequently recurrent. Instability might cause some of these complaints. Best evidence supports the value of the relocation and anterior release tests. Symptoms related to IAP (labral tears) remain unclear. Most promising for establishing labral tears are currently the biceps load I and II, pain provocation of Mimori, and the internal rotation resistance strength tests.

Cartilage, Articular↗

Three-dimensional computed tomography-guided multitract aspiration of extensive ganglionic hemorrhage: technical note.

BACKGROUND: We describe a methodology for effectively improving the lysis and drainage of intracerebral hematomas during stereotactic surgery. METHODS: Stereotactic aspiration using a multitrack technique was performed in 20 patients with ganglionic hemorrhages perforating into the subcortex. Using 3-dimensional computed tomography (3D-CT) guidance, the trajectories and targets of hematoma drainage were selected to extract most portions of the irregular and expansive intracerebral hematomas. Volumes ranged from 36 to 60 mL (mean, 45 mL). Four to 5 drains were inserted into the parenchymal and ventricular clots. Aspiration and injections of urokinase (5000 IU) were repeated every 2 to 3 hours until the hematoma was almost completely removed. RESULTS: The intended catheters for hematoma aspiration were placed precisely along the predetermined tracks with the aid of 3D-CT visualization. The deep and subcortical hematomas were totally removed within a mean of 10 hours postoperatively. Multiple catheter placements itself caused no complications. Sixteen patients (80%) recovered with a favorable neurological outcome. CONCLUSIONS: The 3D-CT-based multitrack technique is a rapid and effective method for the stereotactic removal of extensive ganglionic hemorrhages. It has the advantage of giving better neurological recovery than conventional stereotactic or microscopic surgery for selected patients.

Adult↗

Water-mediated association provides an ion pair receptor.

In this paper, we report on the formation and properties of a water-stabilized dimer comprising calix[4]arene-guanosine conjugate cG 2. The 1,3-alternate calixarene cG 2 was poorly soluble in dry CDCl(3) and gave an ill-resolved NMR spectrum, consistent with its nonspecific aggregation. The compound was much more soluble in water-saturated CDCl(3). Two sets of well-resolved (1)H NMR signals for the guanosine residues in cG 2, present in a 1:1 ratio, indicated that the compound's D(2) symmetry had been broken and provided the first hint that cG 2 dimerizes in water-saturated CDCl(3). The resulting dimer, (cG 2)(2).(H(2)O)(n)(), has a unique property: it extracts alkali halide salts from water into organic solution. This dimer is a rare example of a self-assembled ion pair receptor. The identity of the (cG 2)(2).NaCl.(H(2)O)(n)() dimer was confirmed by comparing its self-diffusion coefficient in CDCl(3), determined by pulsed-field gradient NMR, with that of control compound cA 3, an adenosine analogue. The dimer's stoichiometry was also confirmed by quantitative measurement of the cation and anion using ion chromatrography. Two-dimensional NMR and ion-induced NMR shifts indicated that the cation binding site is formed by an intermolecular G-quartet and the anion binding site is provided by the 5'-amide NH groups. Once bound, the salt increases the dimer's thermal stability. Both (1)H NMR and ion chromatography measurements indicated that the cG 2 dimer has a modest selectivity for extracting K(+) over Na(+) and Br(-) over Cl(-). The anion's identity also influences the association process: NaCl gives a soluble, discrete dimer whereas addition of NaBPh(4) to (cG 2)(2).(H(2)O)(n)() leads to extensive aggregation and precipitation. This study suggests a new direction for ion pair receptors, namely, the use of molecular self-assembly. The study also highlights water's ability to stabilize a functional noncovalent assembly.

Calixarenes↗

Quick methods to control compliance of plastic materials with food packaging regulations.

A general strategy is presented, aiming to provide plastics manufacturers, food industries and enforcement laboratories with quick methods to check whether migration from materials for food contact will be acceptable during the time of use. The strategy involves several steps, with increasing time demand and cost. Monitoring extraction kinetics allows both the optimization of the extraction time, and the selection of conditions where extraction is more severe than migration. The influence of the extracting solvent is discussed. It may give rise to specific non-extraction of some migrants, which may change the conclusions when the solvent is used in replacement of a fatty food simulant. Factors ruling this effect at a given temperature are identified: the affinity to the solvent with the migrant (selectivity), its ability to reach molecules entangled in the polymeric network (accessibility) and its interaction with the polymer (penetration). The kinetic parameters of the penetration of olive oil into polypropylene have been determined by the determination of profiles of concentration.

Diffusion↗

Characterization of the ATPase activity of P-glycoprotein from multidrug-resistant Chinese hamster ovary cells.

P-Glycoprotein (Pgp) was isolated from CHRC5 membranes by selective detergent extraction and further purified by lentil lectin affinity chromatography. The purified product displayed a very high basal ATPase activity (1.65 mumol/min per mg protein in the absence of added drugs or lipids) with an apparent Km for ATP of 0.4 mM. There was no evidence of cooperativity, suggesting that the two ATP sites operate independently of each other. Pgp ATPase activity was stimulated by verapamil, trifluoperazine and colchicine, and inhibited by daunomycin and vinblastine. All drugs and chemosensitizers acted as mixed activators or inhibitors, producing changes in both the Vmax of the ATPase and the Km for ATP. ADP competitively inhibited Pgp ATPase, with a Ki of 0.2 mM. The macrolide antibiotics bafilomycin A1, concanamycin A and concanamycin B, inhibited Pgp ATPase at concentrations of 0.1-10 microM, and at an inhibitor:protein stoichiometry of 0.65-1.0 mumol/mg protein, which is at the low end of the range characteristic of P-type ATPases. Pgp ATPase was relatively selective for adenine nucleotides. Several phospholipids stimulated Pgp ATPase activity in a dose-dependent manner, whereas others produced inhibition. Metabolic labelling showed that the endogenous phospholipids associated with purified Pgp consisted largely of phosphatidylethanolamine and phosphatidylserine, with only a small amount of phosphatidylcholine. 32P-Labelling studies indicated that purified Pgp was partially phosphorylated. It can be concluded that Pgp is a constitutively active, adenine nucleotide-specific ATPase whose catalytic activity can be modulated by both drugs and phospholipids.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Heavy cigarette smokers show higher mutagenicity in urine.

We examined the mutagenicity of cigarette smoker's urine in 32 healthy male cigarette smoker and 37 healthy male non-smoker. Twenty-four-hour urine specimens were subjected to blue rayon extraction which selectively adsorb polycyclic compounds, after which the elutions were fractionated by carboxymethyl cellulose column chromatography for removing antimutagenic compounds. The mutagens were measured by using an S9-mediated Salmonella mutagenicity test on strain TA98. Compared with those with non-smokers, smokers' urine showed a significantly higher urinary level of mutagens in the acid-elutable and in the sum of all chromatography fractions. A similar tendency was also seen in the alkali-elutable fraction. The subjects were classified into three groups according to the number of smoked cigarettes. Heavy smokers, who smoked more than 20 cigarettes per day, showed a significantly higher urinary level of mutagens than both non-smokers and light smokers especially in the acid-elutable and in the sum of all chromatography fractions. Our findings suggest that smokers are exposed to a great amount of polycyclic carcinogens and mutagens by cigarette smoking. These results also suggest that urinary level of mutagens measured by using blue rayon extraction combined with carboxymethyl cellulose chromatography could be a good index for estimating the exposure to carcinogens and mutagens such as polycyclic compounds.

Adult↗

Use of a multiplex PCR to detect and identify Mycobacterium avium and M. intracellulare in blood culture fluids of AIDS patients.

The presence of mycobacteria in blood culture fluids (BACTEC) of AIDS patients with positive growth indices (GIs, > 20 U) was investigated by using a multiplex PCR to detect and identify members of the genus Mycobacterium, M. avium, M. intracellulare, and M. tuberculosis. Three different methods of extracting mycobacterial DNA from blood culture fluid were compared for use with the multiplex PCR. Mycobacterial cells were pelleted from a small aliquot of blood culture fluid by centrifugation, and the DNA was extracted from cells by heat lysis or a sodium iodide-isopropanol or a phenol-chloroform method. DNAs of different sizes were amplified from a region of the MPB70 gene of M. tuberculosis (372 bp) and from a region of the 16S rRNA gene of members of the genus Mycobacterium (1,030 bp), M. intracellulare (850 bp), or M. avium (180 bp) as a multiplex PCR in a single tube. The amplified DNA products were detected by agarose gel electrophoresis and ethidium bromide staining in all 41 (100%) positive cultures after sodium iodide-isopropanol extraction, in 18 (44%) after heat lysis, and in 5 (12%) after phenol-chloroform extraction. Of the 41 positive cultures, 38 were identified as M. avium and 2 were identified as M. intracellulare by both routine methods and multiplex PCR. The remaining mycobacterium was identified as M. intracellulare by routine methods and as M. avium by the multiplex PCR. Another six blood cultures that were negative for the presence of acid-fast bacilli after Ziehl-Neelson staining were also negative by PCR. The study shows that the multiplex PCR is a useful method for the detection and identification of either M. avium or M. intracellulare in small samples of cultured BACTEC 13A fluid with positive GIs ranging from 21 to 999 U. The average time to positive GI was 18 days (median, 13 days) and ranged between 8 and 42 days. The multiplex PCR may permit cultured mycobacteria to be identified at an earlier stage than the routine methods which have been adapted for use with the BACTEC system. The results also show that the method selected for extracting mycobacterial DNA from blood culture fluids is crucial for providing sensitive and accurate PCR results.

AIDS-Related Opportunistic Infections↗

Distribution of immunoreactive prolactin in the male and female rat brain: effects of hypophysectomy and intraventricular administration of colchicine.

Immunohistochemical studies have identified immunoreactive prolactin (IR-PRL) in the hypothalamus and other areas of the rat brain. However, immunocytochemical techniques make it difficult to quantify the amount of antigen localized in a specific region. In this study, IR-PRL was extracted from selected regions of the rat brain, consisting of the median eminence, dorsal and ventral hypothalamus, thalamus, amygdalae, cerebellum, cortex, hippocampus, septum, pons-medulla, and olfactory lobes, and the concentrations of IR-PRL were determined by radioimmunoassay. Whereas IR-PRL was detected in all brain regions in both the male and the female rat brain, the concentrations of IR-PRL in the female rat were significantly greater than those measured in the corresponding region of the male rat brain. In the female rat, hypophysectomy significantly reduced, but did not eliminate, the concentration of IR-PRL in hypothalamus, amygdala, thalamus, and pons-medulla. In contrast, hypophysectomy did not affect the concentration of IR-PRL in any brain regions of the male rat. Injection of colchicine into the lateral ventricle decreased the concentration of IR-PRL in the median eminence and increased the concentration of IR-PRL in the ventral hypothalamus in male and female rats. In addition, extracted hypothalamic and pituitary IR-PRL displayed similar dilution curves in the PRL assay and elution patterns on Sephadex G-100. These data indicate that both the male and the female rat brain contains an IR-PRL-like material with physicochemical properties similar to those of pituitary PRL. This material is differentially distributed in the male and female brain and is found in greater concentrations in the female brain.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Hypothermic circulatory arrest and other methods of cerebral protection during operations on the thoracic aorta.

Current surgical techniques in operations on the thoracic aorta frequently require exclusion of the cerebral circulation for varying periods. During these periods, hypothermic circulatory arrest (HCA), selective cerebral perfusion (SCP), and retrograde cerebral perfusion (RCP) can be used for cerebral protection. Hypothermia is the principle component of these methods of protection. The main protective effect of hypothermia is based on reduction of cerebral energy expenditures and largely depends on adequate suppression of cerebral function. It is most effective at deep hypothermic levels (13 degrees C to 15 degrees C). Measures that preserve autoregulation of cerebral blood flow help increase the margin of safety with all methods of protection. There is solid experimental and clinical data indicating the safe limits and outcome following HCA. Current applications of SCP and RCP are fairly recent developments and do not have comparable supporting data. SCP can be used without deep hypothermia and allows prolonged periods of cerebral protection, but is complex in application. RCP is simpler, but always requires deep hypothermia. Present clinical data do not allow separation of its protective effect from that of HCA alone. Recent modifications in the application of HCA include monitoring of cerebral O2 extraction, and selective use of supplemental SCP to limit arrest times to less than 50 minutes, or RCP to prevent embolic strokes, as indicated. These changes appear to have reduced the overall mortality, the severity of embolic strokes, and stroke-related mortality.

Adult↗

Screening of Thai medicinal plant extracts and their active constituents for in vitro antimalarial activity.

To discover antimalarial substances from plants cultivated in Thailand 80%-EtOH extracts from selected plants were screened for in vitro antimalarial activity against the drug resistant K1 strain of Plasmodium falciparum. In total, 86 Thai medicinal plant samples representing 48 species from 35 genera in 16 families were screened and two species (Polyalthia viridis and Goniothalamus marcanii) were found to show notable antimalarial activity (IC50: 10.0 and 6.3 microg/mL). Marcanine A and 16-hydroxycleroda-3,13(14)Z-dien-15,16-olide were identified as the respective major active constituents in P. viridis and G. marcanii, respectively.

Animals↗

Metal fractionation studies in surfacial and core sediments in the Achankovil River Basin in India.

The Fractionation of Fe, Zn, Cu, Pb, Mn and Cd in the sediments of the Achankovil River, Western Ghats, India using a sequential extraction method was carried out to understand the metal availability in the basin for biotic and abiotic activities. Spatial distribution of heavy metals has been studied. Sediment grain size has significant control over the heavy metal distribution. The fluctuations in their concentration partly depend upon the lithology of the river basin and partly the anthropogenic activities. The sediments are dominated by sand and are moderately to strongly positively skewed and are very leptokurtotic in nature. The quartzite and feldspars are abundant minerals along with significant amount of mica with low clay content. The core sediments show increasing trend of heavy metal concentration with depth due to the recent addition of anthropogenic sources and post-diagenic activities. Significant amount of Cd (18%) was found in carbonate fraction, which may pose environmental problems due to its toxic nature. Small concentrations of metals, except Cd and Cu, are in exchangeable fraction, which indicate low bio-availability. Enrichment Factor (EF) for individual metals shows the contribution from terrregious and in part from anthropogenic sources. Selective Sequential Extraction (SSE) study shows the variation in specific metal distribution pattern, their distribution in different phases and their bio-availability. Maximum amount of the metals were bound to the non-residual fractions (mainly Fe-oxides). Overall, bio-availability of these micronutrients from sediments seems to be very less. Non-residual phase is the most important phase for majority of heavy metals studied. Among the non-residual fraction, maximum amount of the heavy metals bound to Fe-oxides. The study high lights the need for in-depth study of heavy metals distribution and fractionation in the smaller river basins to get precise information on the behavior and transport of heavy metals in the fluvial environment and their contribution to the world ocean.

Chemical Fractionation↗

St John's wort (Hypericum perforatum): drug interactions and clinical outcomes.

AIMS: The aim of this work is to identify the medicines which interact with the herbal remedy St John's wort (SJW), and the mechanisms responsible. METHODS: A systematic review of all the available evidence, including worldwide published literature and spontaneous case reports provided by healthcare professionals and regulatory authorities within Europe has been undertaken. RESULTS: A number of clinically significant interactions have been identified with prescribed medicines including warfarin, phenprocoumon, cyclosporin, HIV protease inhibitors, theophylline, digoxin and oral contraceptives resulting in a decrease in concentration or effect of the medicines. These interactions are probably due to the induction of cytochrome P450 isoenzymes CYP3A4, CYP2C9, CYP1A2 and the transport protein P-glycoprotein by constituent(s) in SJW. The degree of induction is unpredictable due to factors such as the variable quality and quantity of constituent(s) in SJW preparations. In addition, possible pharmacodynamic interactions with selective serotonin re-uptake inhibitors and serotonin (5-HT(1d)) receptor-agonists such as triptans used to treat migraine were identified. These interactions are associated with an increased risk of adverse reactions. CONCLUSIONS: In Sweden and the UK the potential risks to patients were judged to be significant and therefore information about the interactions was provided to health care professionals and patients. The product information of the licensed medicines involved has been amended to reflect these newly identified interactions and SJW preparations have been voluntarily labelled with appropriate warnings.

Contraceptives, Oral↗

Sensitive triple-quadrupole mass spectrometric assay for the determination of BMS-181885, a 5-HT1 agonist, in human plasma following solid phase extraction.

A sensitive, selective, accurate, precise and reproducible triple-quadrupole liquid chromatographic-mass spectrometric assay was developed and validated for BMS-181885 (I), a 5HT1 agonist, in human plasma using BMS-181101 as the internal standard (IS). The method involved solid phase extraction of plasma containing I and the IS using Isoelute CN cartridges. The supernatant was then evaporated to dryness at 40 degrees C. The residue was dissolved in 100 microL of the injecting solvent. The HPLC column was ODS-3, 2 x 100 mm. The mobile phase comprised 10 mM ammonium formate (pH = 4) and acetonitrile, 55:45 v/v, used in an isocratic condition. The mass spectrometer was programmed to admit the protonated molecules at m/z 461 (I) and m/z 370 (IS) via the first quadrupole filter and to select reaction monitoring of ions at m/z 152 for I and IS for the quantification. Standard curves were fitted to a weighted quadratic function over the concentration range 0.2-200 ng/mL. The lowest standard concentration (0.2 ng/mL) was experimentally established as the lower limit of quantitation of the assay. The mean predicted quality control concentrations deviated within +/- 11% of the corresponding nominal values; the intra-assay and inter-assay precisions were within 7.0% relative standard deviation. I was stable in the injection solvent at 4 degrees C for at least 24 h and for at least three freeze-thaw cycles. Freezer stability of I in plasma was demonstrated for at least 3 months. The extraction recovery of I was established as 97%. The validated assay was applied to a pharmacokinetic study of I in humans.

Analysis of Variance↗

Thrombolysis for acute deep vein thrombosis.

BACKGROUND: Standard treatment for deep vein thrombosis (DVT) aims to reduce immediate complications. Use of thrombolysis or clot dissolving drugs could reduce the long-term complications of post-thrombotic syndrome (pain, swelling, skin discolouration, or venous ulceration) in the affected leg. OBJECTIVES: To determine the efficacy and safety of thrombolysis for DVT. SEARCH STRATEGY: Publications describing randomised controlled trials (RCTs) of thrombolysis versus anticoagulation for acute DVT were sought through electronic searches of the Cochrane Peripheral Vascular Diseases trials register (last searched April 2004) and the Cochrane Central Register of Controlled Trials (CENTRAL) (last searched The Cochrane Library Issue 2, 2004). Additional trials were identified by reviewing reference lists of papers. There were no restrictions for language. SELECTION CRITERIA: RCTs examining thrombolysis versus anticoagulation for acute DVT and/or calf vein thrombosis were considered. DATA COLLECTION AND ANALYSIS: One reviewer (LIW) selected trials, extracted data and assessed study quality, with checking at all stages by the other reviewer (MPA). Where required, additional information was sought from trialists. MAIN RESULTS: Twelve studies were included. Complete clot lysis occurred significantly more often in the treatment group in early follow up, (relative risk (RR) 0.24; 95% confidence interval (CI) 0.07 to 0.82), and in late follow up, (RR 0.37; 95 % CI 0.25 to 0.54). A similar effect was also seen for any degree of improvement in venous patency. Significantly less post-thrombotic syndrome occurred in those receiving thrombolysis, (RR 0.66; 95 % CI 0.47 to 0.94). Leg ulceration was reduced although the data were limited by small numbers, (RR 0.53; 95 % CI 0.12 to 2.43). Venous function was improved at late follow up, but not significantly (RR 0.43; 95 % CI 0.06 to 3.17)Out of 668 patients, those receiving thrombolysis had significantly more bleeding complications, (RR 1.73; 95 % CI 1.04 to 2.88). Two strokes occurred in the treatment group (RR 1.70; 95 % CI 0.21 to 13.70). The incidence of bleeding appears to have reduced over time with the introduction of stricter selection criteria. There was no significant effect on mortality detected in either early or late follow up. Data on occurrence of pulmonary embolism (PE) and recurrent DVT were inconclusive. REVIEWERS' CONCLUSIONS: Thrombolysis appears to offer advantages in terms of reducing post-thrombotic syndrome and maintaining venous patency after DVT. Use of strict eligibility criteria has improved the safety and acceptability of this treatment. The optimum drug, dose and route of administration have yet to be determined.

Humans↗