Interventions for trachoma trichiasis

BACKGROUND

Trachoma is a leading cause of avoidable blindness. The World Health Organization recommends eliminating trachoma blindness by the SAFE strategy incorporating Surgery, Antibiotic treatment, Facial cleanliness and Environmental hygiene.

OBJECTIVES

This review examined the evidence for the effectiveness of different interventions for trachoma trichiasis.

SEARCH STRATEGY

We identified trials from the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (2005, Issue 3), MEDLINE (1966 to September 2005) PubMed (searched on 21-09-06; last 90 days), EMBASE (1980 to September 2005), LILACS (March 2004) and the reference lists of included studies. We also contacted authors for details of other relevant studies.

SELECTION CRITERIA

We included randomised trials of any intervention intended to treat trachoma trichiasis and trials comparing different methods of delivering the same intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials. We contacted trial authors for missing data when necessary.

MAIN RESULTS

Seven studies met the inclusion criteria. Three studies compared different surgical interventions. These trials suggest the most effective surgery is full-thickness incision of the tarsal plate and rotation of the terminal tarsal strip 180 degrees. One study showed that bilamellar rotation was more effective than unilamellar rotation but the other two studies did not. One trial found double-sided sticking plaster more effective than epilation for the immediate management of trichiasis but required frequent replacement (odds ratio (OR) 0.01, 95% confidence interval (CI) 0.00 to 0.22). Another trial found community-based surgery increased convenience for patients without increasing the risk of complications or recurrence when compared to health centres. One trial found no difference between trichiasis surgery performed by ophthalmologists and integrated eye workers (OR 1.32, 95% CI 0.83 to 2.11). A trial comparing trichiasis surgery with and without concurrent administration of azithromycin found no difference in success rates at one year (OR 0.99, 95% CI 0.67 to 1.46).

AUTHORS' CONCLUSIONS

No trials show interventions for trichiasis prevent blindness. Certain interventions have been shown to be more effective at eliminating trichiasis. Full thickness incision of the tarsal plate and rotation of the lash-bearing lid margin through 180 degrees is probably the best technique and is preferably delivered in the community. The use of double-sided sticking plaster is more effective than epilation as a temporary measure. Surgery may be carried out by an ophthalmologist or a trained ophthalmic assistant. The addition of azithromycin treatment at the time of surgery does not appear to improve outcomes.

Phase 1, pharmacokinetic (PK) and pharmacodynamic (PD) study of of the Hsp-90 inhibitor, KOS-1022 (17-DMAG), in patients with refractory hematological malignancies

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Background: Disruption of Hsp90-client protein heterocomplexes leads to degradation of a variety of oncoproteins. KOS-1022, an Hsp90 inhibitor and water-soluble geldanamycin derivative, is in trials in patients with solid tumors. Compared to a prior geldanamycin derivative (17-AAG), KOS-1022 is ∼3–5 fold more potent (comparing in vitro cytotoxicity or the MTD in toxicology studies on the same schedule). Primary study objectives: establish safety and MTD of KOS-1022 in patients with advanced hematologic malignancies; characterize PK and PD. Methods: Escalating doses of KOS-1022 are given IV over 1 h twice weekly for 2 out of 3 weeks. Plasma KOS-1022 concentrations (1st and 4th infusion, Cycle 1) are quantitated by LC/MS/MS. Pre and on-study CD34+ bone marrow and peripheral blasts undergo flow cytometry to quantify Hsp70/90, pAKT/total AKT, markers of apoptosis and proliferation. Response in AML pts used IWG criteria. Results: 13 pts have been enrolled at doses of 8 (n=4), 16 (n=6), 24 (n=1) and 32 mg/m2 (n=2). All were AML (except 1 CML). Most (n=11) patients had 2–3 prior induction regimens. DLT was seen in 2 pts at 32 mg/m2 (acute myocardial infarction and elevation of troponin). Both patients had significant co-morbidity, including (1) prior myocardial infarction and (2) progressive AML with a similar troponin elevation during induction chemotherapy prior to study. Common drug-related toxicities (all Grade 1–2): fatigue, nausea, diarrhea and arthralgias. From 8 to 32 mg/m2, approximately linear PK was observed. Mean terminal half-lives varied from 13.0–31.2 hours. Day 1 clearance for 8, 16 and 32 mg/m2 was 5.6, 9.7 and 10.8 L/hr/m2; mean Vz (L/m2) for these groups were 238, 433 and 489. Although pre-infusion drug was quantifiable on Day 11 in most patients, Day 11/Day 1 AUC0–25h ratio was 0.96. Activity in AML: 2 CRi and 1 SD x 9 cycles were observed. Comparing BMAs taken at Day 8 and Day 15 to baseline: decreased Hsp90 (41% to 13%), increased Hsp70 (8% to 84%) with decreased pAKT (Ser), pAKT (Thr) and total AKT in CD34+ cells. Conclusions: KOS-1022 appears to be well tolerated, with preliminary signs of clinical and biologic activity in refractory leukemia. MTD has not been defined. Plasma PK is linear over this dose range.

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Evaluation of novel beta-ribosidase substrates for the differentiation of Gram-negative bacteria

AIMS

To synthesize novel substrates for the detection of beta-ribosidase and assess their potential for the differentiation of Gram-negative bacteria.

METHODS AND RESULTS

Two novel chromogenic substrates, 3',4'-dihydroxyflavone-4'-beta-D-ribofuranoside (DHF-riboside) and 5-bromo-4-chloro-3-indolyl-beta-D-ribofuranoside (X-riboside) were evaluated along with a known fluorogenic substrate, 4-methylumbelliferyl-beta-D-ribofuranoside (4MU-riboside). A total of 543 Gram-negative bacilli were cultured on media containing either DHF-riboside or X-riboside. Hydrolysis of DHF-riboside or X-riboside resulted in the formation of clearly distinguishable black or blue-green colonies, respectively. Hydrolysis of 4MU-riboside was evaluated in a liquid medium in microtiter trays and yielded blue fluorescence on hydrolysis which was measured using fluorimetry. beta-Ribosidase activity was widespread with 75% of strains, including 85.6% of Enterobacteriaceae, showing activity with at least one substrate. Genera that demonstrated beta-ribosidase activity included Aeromonas, Citrobacter, Enterobacter, Escherichia, Hafnia, Klebsiella, Morganella, Providencia, Pseudomonas, Salmonella and Shigella. In contrast, strains of Proteus spp., Acinetobacter spp., Yersinia enterocolitica, Vibrio cholerae and Vibrio parahaemolyticus generally failed to demonstrate beta-ribosidase activity.

CONCLUSIONS

The novel substrates DHF-riboside and X-riboside are effective for the detection of beta-ribosidase in agar-based media and may be useful for the differentiation and identification of Gram-negative bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report describing the application and utility of chromogenic substrates for beta-ribosidase. These substrates could be applied in chromogenic media for differentiation of Gram-negative bacteria.

Outcome of complex fractures of the tibial plateau treated with a beam-loading ring fixation system

Fine-wire accepted as a minimally external fixation is invasive technique, which can provide better outcomes than traditional open methods in the management of complex fractures of the tibial plateau. Available fixators vary in their biomechanical stability, and we believe that a stable beam-loading system is essential for consistently good outcomes. We assessed, prospectively, the clinical, radiological and general health status of 20 of 21 consecutive patients with complex fractures of the tibial plateau who had been treated using a standard protocol, with percutaneous screw fixation and a neutralisation concept with a fine wire beam-loading fixator allowing early weight-bearing.

Bony union was achieved in all patients, with 85% having good or excellent results. Full weight-bearing started during the first six weeks in 60% of patients. The general health status assessment correlated well with the knee scores and reflected a satisfactory outcome.

FTIR remote sensing of fractional magma degassing at Mount Etna, Sicily

The chemical composition of volcanic gas emissions from each of the four summit craters of Mount Etna was measured remotely in May 2001, using a Fourier transform infrared (FTIR) spectrometer operated on the upper flanks of the volcano. The results reveal constant HCl/HF ratio but distinct SO2/HCl and SO2/HF ratios in the emitted gases, which, in the light of melt inclusion data for Etna basalts, can be interpreted in terms of escape of gases from partially, and variably, degassed magma at different depths beneath the summit. Gases released from the three main summit craters (Bocca Nuova, Voragine, and Northeast) had an identical composition, controlled by bulk degassing of a single magma body that had previously lost c. 25% of its original sulphur. The similar gas composition at all three main craters suggests that these are connected to a central conduit system that branches at relatively shallow depth. Measurements of the bulk volcanic plume on the same day, c. 7 km downwind, show that degassing from these craters dominated the total gas output of the volcano, and that no significant chemical evolution occurred within the plume over a time-scale of c. 12 min. Weaker gas emissions from the Southeast crater were comparatively depleted in SO2 (SO2/HCl and SO2/HF ratios a factor of two lower), implying that this crater is fed either by a separate conduit or by a branch of the central conduit whose geometry favours solubility-controlled volatile fractionation. Still lower SO2/HCl and SO2/HF ratios measured for residual degassing of a lava flow erupted from the Southeast crater verify the lower solubility and earlier escape of sulphur compared to halogens at Etna. Fractional magma degassing is also implied by strong chemical contrasts between the bulk volcanic plume and fissure gas emissions measured during the July-August 2001 flank eruption. These results highlight the ability of FTIR spectrometry to detect fine spatial and temporal variations in magma degassing processes, and thereby constrain models of shallow plumbing systems.

Randomised trial of SIR-Spheres plus chemotherapy vs. chemotherapy alone for treating patients with liver metastases from primary large bowel cancer

PURPOSE

SIR-Spheres are radioactive yttrium90 microspheres (SIR-Spheres, Sirtex Medical Limited, Australia) used to selectively target high levels of ionising radiation to tumors within the liver. This trial was designed to measure any increased patient benefit by adding a single administration of SIR-Spheres to a regimen of regional hepatic artery chemotherapy (HAC) administered as a 12 day infusion of floxuridine and repeated at monthly intervals, vs. the same chemotherapy alone.

PATIENTS AND METHODS

A phase III randomised clinical trial entering 74 patients was undertaken on patients with bi-lobar non-resectable liver metastases from primary adenocarcinoma of the large bowel. Patient benefit criteria assessed in the trial were tumor response, time to disease progression in the liver, overall survival, quality of life, and treatment related toxicity. Tumor response was measured by serial changes in both cross-sectional tumor areas and total tumor volumes, provided any response lasted not less than three months as well as changes in serum carcino-embryonic antigen (CEA).

RESULTS

The partial and complete response rate (PR + CR) was significantly greater for patients receiving SIR-Spheres when measured by tumor areas (44%) vs. 17.6%, P = 0.01) tumor volumes (50% vs. 24%, P = 0.03) and CEA (72% vs. 47%, P = 0.004). The median time to disease progression in the liver was significantly longer for patients receiving SIR-Spheres in comparison to patients receiving HAC alone when measured by either tumor areas (9.7 vs. 15.9 months, P = 0.001), tumor volumes (7.6 vs. 12.0 months, P = 0.04) or CEA (5.7 vs. 6.7 months, P = 0.06). The one, two, three and five-year survival for patients receiving SIR-Spheres was 72%, 39%, 17% and 3.5%, compared to 68%, 29%, 6.5% and 0% for HAC alone. Cox regression analysis suggests an improvement in survival for patients treated with SIR-Spheres who survive more than 15 months (P = 0.06). There was no increase in grade 3-4 treatment related toxicity and no loss of quality of life for patients receiving SIR-Spheres in comparison to patients receiving HAC alone.

CONCLUSION

The combination of a single injection of SIR-Spheres plus HAC is substantially more effective in increasing tumor responses and progression free survival than the same regimen of HAC alone.

The use of trans-articular and extra-articular external fixation for management of distal tibial intra-articular fractures

Twenty-nine consecutive cases of distal tibial intra-articular fractures treated by trans-articular or extra-articular external fixation techniques have been reviewed. Eleven cases were treated initially with a trans-articular dynamic axial fixator. Of these seven were converted to an extra-articular SHF, for a combination of poor ankle motion and delayed healing of the metaphyseo-diaphyseal dissociation (MDD). Three of these cases (two patients) required bone grafting for delayed healing of the diaphyseal component of the fracture. Apart from one refracture through the MDD, no major complications were seen. No deep infections and no angular malalignments were noted. There were 11 pin track infections. Subjective assessment using short form-36 (SF-36) questionnaires, however, revealed significant differences compared to a normal population particularly in physical function and pain at a mean follow-up of 21 months. Using Bone's criteria for assessment of range of motion there were 62% excellent and good results, which dropped to 53% when fractures with a metaphyseo-diaphyseal extension were included. The use of minimally invasive techniques of internal fixation and stabilisation with a Sheffield hybrid frame in the management of distal tibial intra-articular fractures has minimal complications. Trans-articular external fixation is a good primary treatment for badly comminuted articular fractures with poor soft tissue condition. Conversion to extra-articular external fixation is recommended for slower healing fractures allowing ankle movement and early weight-bearing. The presence of a MDD dissociation lengthens the treatment time significantly, adds to the morbidity and affects final outcome.

Catechol derivatives of aminopyrazine and cell protection against UVB-induced mortality

A series of 5-aryl- and 3,5-bis-aryl-2-amino-1,4-pyrazine derivatives 4 and 6, and related imidazolopyrazinones 7, has been synthesized, the aryl groups of which are catechol and/or phenol substituents. These compounds, tested against human keratinocyte cells stressed by UVB irradiation, showed high antioxidative properties. One compound (6f) was more active than EGCG/ECG (green tea extract) in reducing cell mortality.

Cell contact dependent extended release of adenovirus by microparticles in vitro

Adenoviral vectors remain one of the most promising methods of gene delivery but are plagued by several inherent problems including immune inactivation and transient expression. This paper reports a novel microparticle-based delivery system for adenovirus that allows high uptake of virus, stable complex formation and extended release. In addition, this microparticle/adenovirus complex has been demonstrated to only release virus upon cell contact. The significant clinical implications of this delivery system are discussed.

National survey of counsellors working in primary care: evidence for growing professionalisation?

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Involvement of Rb family proteins, focal adhesion proteins and protein synthesis in senescent morphogenesis induced by hydrogen peroxide

Early passage human diploid fibroblasts develop senescent morphology prematurely within a week after a 2-hour pulse treatment with low or mild dose H(2)O(2). We test here the role of cell cycle checkpoints, cytoskeletal proteins and de novo protein synthesis in senescent morphogenesis following H(2)O(2) treatment. H(2)O(2) treatment causes transient elevation of p53 protein and prolonged inhibition of Rb hyperphosphorylation. Expression of human papillomaviral E6 gene prevented elevation of p53 but did not affect senescent morphogenesis. Expression of human papillomaviral E7 gene reduced the level of Rb protein and prevented induction of senescent morphology by H(2)O(2). The mutants of the E7 gene, in which the Rb family protein binding site was destroyed, could not reduce Rb protein or prevent H(2)O(2) from inducing senescent morphology. Senescent-like cells showed enhanced actin stress fibers. In untreated cells, vinculin and paxillin preferentially distributed along the edge of the cells. In contrast, vinculin and paxillin distributed randomly and sporadically throughout senescent-like cells. E7 expression prevented enhancement of actin filament formation and redistribution of vinculin or paxillin. Neither wild-type nor E7 cells showed changes in the protein level of actin, vinculin or paxillin measured by western blot after H(2)O(2) treatment. Finally, depletion of methionine in the culture medium after H(2)O(2) treatment prevented senescent morphogenesis without affecting dephosphorylation of Rb protein. Our results suggest that senescent morphology likely develops by a program involving activated Rb family proteins, enhancement of actin stress fibers, redistribution of focal adhesion proteins and de novo protein synthesis.

Posttransplantation lymphoproliferative disorder: endoscopic findings

BACKGROUND

Posttransplantation lymphoproliferative disorder (PTLD) may manifest a variety of nonspecific symptoms and must be suspected in the patient who undergoes solid organ transplantation. Common sites of occurrence include the gastrointestinal tract, the central nervous system, and lymphoid tissue of the oral pharynx, mediastinum, and mesentery. The large incidence of gastrointestinal involvement provides an opportunity for endoscopic diagnosis. This is the description of a characteristic endoscopic finding in patients who have undergone liver transplantation who are under evaluation for suspected PTLD.

METHODS

During a 2-year period, 27 liver transplantations were performed in 24 pediatric patients. Fourteen patients underwent endoscopic evaluation. Indications for endoscopy included abdominal pain, vomiting, hematemesis, irritability, growth failure, anemia, occult blood loss, and suspected PTLD. Biopsy specimens were obtained from any endoscopically detected abnormality and from the duodenum, gastric antrum, esophagus, terminal ileum, cecum, and rectum. Specimens with suspected PTLD were evaluated with Epstein-Barr virus latent membrane stain.

RESULTS

Six patients were found to have a characteristic lesion, which was raised, rubbery, and erythematous, with a central ulceration. Lesions were singular or multiple and ranged from 5 to 15 mm in diameter. Microscopic evaluation revealed a monotonous proliferation of lymphocytes. All specimens were positive for Epstein-Barr virus latent membrane protein stain. Stains for cytomegalovirus were negative. Biopsy specimens from the eight patients without identified characteristic lesions were negative for PTLD.

CONCLUSIONS

Panendoscopy is a useful tool for the diagnosis and treatment of gastrointestinal PTLD. Endoscopy is easily accomplished, may provide an instantaneous result if the characteristic lesion is identified, and provides tissue for disease classification. Patients with unexplained gastrointestinal signs or symptoms should undergo panendoscopy for suspected PTLD.

Improved muscle-derived expression of human coagulation factor IX from a skeletal actin/CMV hybrid enhancer/promoter

Hemophilia B is caused by the absence of functional coagulation factor IX (F.IX) and represents an important model for treatment of genetic diseases by gene therapy. Recent studies have shown that intramuscular injection of an adeno-associated viral (AAV) vector into mice and hemophilia B dogs results in vector dose-dependent, long-term expression of biologically active F.IX at therapeutic levels. In this study, we demonstrate that levels of expression of approximately 300 ng/mL (6% of normal human F.IX levels) can be reached by intramuscular injection of mice using a 2- to 4-fold lower vector dose (1 x 10(11) vector genomes/mouse, injected into 4 intramuscular sites) than previously described. This was accomplished through the use of an improved expression cassette that uses the cytomegalovirus (CMV) immediate early enhancer/promoter in combination with a 1.2-kilobase portion of human skeletal actin promoter. These results correlated with enhanced levels of F.IX transcript and secreted F.IX protein in transduced murine C2C12 myotubes. Systemic F.IX expression from constructs containing the CMV enhancer/promoter alone was 120 to 200 ng/mL in mice injected with 1 x 10(11) vector genomes. Muscle-specific promoters performed poorly for F.IX transgene expression in vitro and in vivo. However, the incorporation of a sequence from the alpha-skeletal actin promoter containing at least 1 muscle-specific enhancer and 1 enhancer-like element further improved muscle-derived expression of F.IX from a CMV enhancer/promoter-driven expression cassette over previously published results. These findings will allow the design of a clinical protocol for therapeutic levels of F.IX expression with lower vector doses, thus enhancing efficacy and safety of the protocol. (Blood. 2000;95:2536-2542)

Human T-cell leukemia virus type 1 Tax shuttles between functionally discrete subcellular targets

Human T-cell leukemia virus type 1 (HTLV-1) Tax is a nuclear protein with striking pleiotropic functionality. We recently demonstrated that Tax localizes to a multicomponent nuclear speckled structure (Tax speckled structure [TSS]). Here, we examine these structures further and identify a partial overlap of TSS with transcription hot spots. We used a strategy of directed expression via fusion proteins to determine if these transcription sites are the subtargets within TSS required for Tax function. When fused to human immunodeficiency virus type 1 (HIV-1) Tat, the resulting Tat-Tax fusion protein displayed neither a Tat-like nor a Tax-like pattern but rather was targeted specifically to the transcription subsites. The Tat-Tax fusion was able to activate both the HIV-1 long terminal repeat (LTR) and the HTVL-1 LTR at the same level as the individual component; thus, targeting proteins to transcription hot spots was compatible with both Tax and Tat transcription function. In contrast, the fusion with HIV-1 Rev, Rev-Tax, resulted in a pattern of expression that was largely Rev-like (nucleolar and cytoplasmic). The reduced localization of Rev-Tax to transcription sites was reflected in a 10-fold drop in activation of the HTLV-1 LTR. However, there was no loss in the ability of Tax to activate via NF-kappaB. Thus, NF-kappaB-dependent Tax function does not require targeting of Tax to these transcription sites and suggests that activation via NF-kappaB is a cytoplasmic function. Selective mutation of the nuclear localization signal site in the Rev portion resulted in retargeting of Rev-Tax to TSS and subsequent restoration of transcription function, demonstrating that inappropriate localization preceded loss of function. Mutation of the nuclear export signal site in the Rev portion had no effect on transcription, although the relative amount of Rev-Tax in the cytoplasm was reduced. Finally, in explaining how Tax can occupy multiple subcellular sites, we show that Tax shuttles from the nucleus to the cytoplasm in a heterokaryon fusion assay. Thus, pleiotropic functionality by Tax is regulatable via shuttling between discrete subcellular compartments.

Induction of replicative senescence biomarkers by sublethal oxidative stresses in normal human fibroblast

We tested the long-term effects of sublethal oxidative stresses on replicative senescence. WI-38 human diploid fibroblasts (HDFs) at early cumulative population doublings (CPDs) were exposed to five stresses with 30 microM tert-butylhydroperoxide (t-BHP). After at least 2 d of recovery, the cells developed biomarkers of replicative senescence: loss of replicative potential, increase in senescence-associated beta-galactosidase activity, overexpression of p21(Waf-1/SDI-1/Cip1), and inability to hyperphosphorylate pRb. The level of mRNAs overexpressed in senescent WI-38 or IMR-90 HDFs increased after five stresses with 30 microM t-BHP or a single stress under 450 microM H(2)O(2). These corresponding genes include fibronectin, osteonectin, alpha1(I)-procollagen, apolipoprotein J, SM22, SS9, and GTP-alpha binding protein. The common 4977 bp mitochondrial DNA deletion was detected in WI-38 HDFs at late CPDs and at early CPDs after t-BHP stresses. In conclusion, sublethal oxidative stresses lead HDFs to a state close to replicative senescence.

Coexpression of factor VIII heavy and light chain adeno-associated viral vectors produces biologically active protein

We are interested in using recombinant adeno-associated viral vectors in the treatment of hemophilia A. Because of the size constraints of recombinant adeno-associated viral vectors, we delivered the heavy and light chains of the human factor 8 (hFVIII) cDNA independently by using two separate vectors. Recombinant AAV vectors were constructed that utilized the human elongation factor 1alpha promoter, a human growth factor polyadenylation signal, and the cDNA sequences encoding either the heavy or light chain of hFVIII. Portal vein injections of each vector alone, a combination of both vectors, or a hFIX control vector were performed in C57BL/6 mice. An ELISA specific for the light chain of hFVIII demonstrated very high levels (2-10 microgram/ml) of protein expression in animals injected with the light chain vector alone or with both vectors. We utilized a chromogenic assay in combination with an antibody specific to hFVIII to determine the amount of biologically active hFVIII in mouse plasma. In animals injected with both the heavy and light chain vectors, greater than physiological levels (200-400 ng/ml) of biologically active hFVIII were produced. This suggests that coexpression of the heavy and light chains of hFVIII may be a feasible approach for treatment of hemophilia A.