Cell Count Loss Research Articles

Phacoemulsification versus manual small‐incision cataract surgery for age‐related cataract: meta‐analysis of randomized controlled trials

To compare outcomes of phacoemulsification (PE) with manual small-incision cataract surgery (MSICS) for age-related cataract. Meta-analysis. Patients from previously reported randomized controlled trials (RCTs) of PE and MSICS with clinical outcomes. A comprehensive literature search of Cochrane Library, PubMed and EMBASE to identify relevant RCTs comparing PE and MSICS. A meta-analysis was performed on the results and a RevMan 5.0 software (version 5.0; Cochrane Collaboration, Oxford, UK) was used for data analysis. Primary outcome measures included best corrected vision acuity (BCVA), uncorrected visual acuity (UCVA). Secondary outcome measures included surgically induced astigmatism (SIA), percentage of endothelial cell count (ECC) loss and complications. Six RCTs describing a total of 1315 eyes were identified. There were no significant differences between the techniques regarding the BCVA 6/9 or better (P = 0.69) and less than 6/18 (P = 0.68), percent of ECC loss (P = 0.45), intraoperative or postoperative complications (P = 0.44 and P = 0.87, respectively). However, a greater proportion of patients in the PE group had final UCVA ≥ 6/9 (P = 0.03), whereas a greater proportion of patients in the MSICS group had final UCVA < 6/18 (P = 0.03). Moreover, PE group induced less SIA (P < 0.00001). PE is superior to MSICS in UCVA and causes less SIA, but there were no significant differences in visual rehabilitation, ECC loss and complication rates between the two techniques.

Effect of bevel position on the corneal endothelium after phacoemulsification

To compare the extent of corneal endothelial (CE) cell loss changes in two groups of eyes submitted to phacoemulsification, with the conventional bevel-up tip position in one eye and with the bevel-down tip position in the fellow eye. This prospective clinical trial comprised 25 patients with bilateral cataracts subjected to lens removal by phacoemulsification with the conventional bevel-up tip position (GI) in one eye and with the bevel-down tip position (GII) in the fellow eye. The nuclei were graded clinically on the basis of hardness. The endothelial cell count (ECC) was evaluated preoperatively and 1, 3 and 6 months postoperatively. Total surgical time, effective ultrasound time and complications were also compared between the groups. Statistical analysis was performed by the Tukey Studentized Range test, with repeated measures for the selected periods. For the other parameters a paired t test was used. Data are presented as mean ± SD, with the level of significance set at p≤0.05. The mean effective ultrasound time was 8.08 ± 6.75 seconds in group I and 7.00 ± 5.75 seconds in GII (P=0.1792) and total surgical time was 10.01 ± 2.46 minutes in GI and 9.86 ± 2.17 minutes in GII (p=0.6267), respectively. The paired t test revealed no statistical differences between the groups. Complications were also similar between the groups. Mean endothelial cell count loss was 6.9% in GI and 2.8% in GII at one month; 6.9% in GI and 3.6% in GII at three months and 11.9% in GI and 7.6% in GII at six months postoperatively. Comparison of endothelial cell count (ECC) showed a statistically significant difference between the groups during the postoperative period. The conventional bevel-up tip position has a negative effect on corneal endothelial cells compared with the bevel-down position. Since the results of other surgical parameters were similar, the bevel-down tip position should be considered as an option in non-complicated phacoemulsification.

Mortality after failure of antiretroviral therapy in sub‐Saharan Africa

To assess the outcome of patients who experienced treatment failure with antiretrovirals in sub-Saharan Africa. Analysis of 11 antiretroviral therapy (ART) programmes in sub-Saharan Africa. World Health Organization (WHO) criteria were used to define treatment failure. All ART-naive patients aged >or=16 who started with a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen and had at least 6 months of follow-up were eligible. For each patient who switched to a second-line regimen, 10 matched patients who remained on a non-failing first-line regimen were selected. Time was measured from the time of switching, from the corresponding time in matched patients, or from the time of treatment failure in patients who remained on a failing regimen. Mortality was analysed using Kaplan-Meier curves and random-effects Cox models. Of 16 591 adult patients starting ART, 382 patients (2.3%) switched to a second-line regimen. Another 323 patients (1.9%) did not switch despite developing immunological or virological failure. Cumulative mortality at 1 year was 4.2% (95% CI 2.2-7.8%) in patients who switched to a second-line regimen and 11.7% (7.3%-18.5%) in patients who remained on a failing first-line regimen, compared to 2.2% (1.6-3.0%) in patients on a non-failing first-line regimen (P < 0.0001). Differences in mortality were not explained by nadir CD4 cell count, age or differential loss to follow up. Many patients who meet criteria for treatment failure do not switch to a second-line regimen and die. There is an urgent need to clarify the reasons why in sub-Saharan Africa many patients remain on failing first-line ART.

A Comparison of Posterior Lamellar Keratoplasty Modalities: DLEK vs. DSEK

PurposeTo compare clinical outcomes after deep lamellar endothelial keratoplasty (DLEK) with Descemet stripping endothelial keratoplasty (DSEK) performed as initial cases by a single surgeon.MethodsSixteen patients with corneal endothelial were enrolled. Eight patients (8 eyes) underwent DLEK and 8 patients (8 eyes) DSEK. We measured uncorrected visual acuity, best corrected visual acuity (BCVA), manifest refraction, corneal endothelial count, interface opacity via Schiempflug imaging, and contrast sensitivity, as well as tracked postoperative complications over the first postoperative year.ResultsPrimary graft failure occurred in two DLEK cases and one DSEK case, all of which were excluded for further analysis. The average 12-month postoperative BCVA was 20/70 in the DLEK group and 20/50 in the DSEK group, with the difference not statistically significant. No significant differences were identified between the 2 groups in terms of mean spherical equivalent and refractive astigmatism, although individuals in the DSEK group tended toward hyperopia. The average endothelial cell count at postoperative month 12 was 1849±494 in the DLEK group and 1643±417 cells/mm2 in the DSEK group, representing cell losses of 26.2% and 31.9%, respectively. No significant differences in endothelial cell count or endothelial cell loss were observed between groups. Early postoperative donor disc dislocation occurred in two eyes after DLEK and one eye after DSEK. Interface opacities and contrast sensitivities were similarly not significantly different between groups.ConclusionsNo significant differences in any assessed clinical outcome were observed between individuals undergoing DLEK and DSEK, when performed as initial cases by a single surgeon.

Treatment with the Fusion Inhibitor Enfuvirtide Influences the Appearance of Mutations in the Human Immunodeficiency Virus Type 1 Regulatory Protein Rev

The gp41-encoding sequence of the env gene contains in two separate regions the Rev-responsive elements (RRE) and the alternative open reading frame of the second exon of the regulatory protein Rev. The binding of Rev to the RRE allows the transport of unspliced/singly spliced viral mRNAs out of the nucleus, an essential step in the life cycle of human immunodeficiency virus type 1 (HIV-1). In this study, we have investigated whether the fusion-inhibitor enfuvirtide (ENF) can induce mutations in Rev and if these mutations correlate with the classical ENF resistance gp41 mutations and with viremia and CD4 cell count. Specific Rev mutations were positively associated with ENF treatment and significantly correlated with classical ENF resistance gp41 mutations. In particular, a cluster was observed for the Rev mutations E57A (E57A(rev)) and N86S(rev) with the ENF resistance gp41 mutations Q40H (Q40H(gp41)) and L45M(gp41). In addition, the presence at week 48 of the E57A(rev) correlates with a significant viremia increase from baseline to week 48 and with a CD4 cell count loss from baseline to week 48. By modeling the RRE structure, we found that the Q40(gp41) and L45(gp41) codons form complementary base pairs in a region of the RRE involved in Rev binding. The conformation of this Rev-binding site is disrupted when Q40H(gp41) and L45M(gp41) occur alone while it is restored when both mutations are present. In conclusion, our study shows that ENF pressure may also affect both Rev and RRE structures and can provide an excellent example of compensatory evolution. This highlights the multiple roles of ENF (and perhaps other entry inhibitors) in modulating the correct interplay between the different HIV-1 genes and proteins during the HIV-1 life cycle.

The Effect of Capsular Tension Ring on Posterior Capsular Opacity in Cataract Surgery

This study was performed to evaluate the efficacy and safety of the capsular tension ring on posterior capsular opacity in comparison with cases undergoing intraocular lens (IOL) implantation alone. We analyzed 127 eyes which had undergone cataract surgery, including capsular tension ring insertion, along with 127 eyes which had undergone IOL implantation alone by the same surgeon from September 1998 to March 2003. In the insertion group, 41 eyes (group A) had been followed up for more than one year after silicone IOL implantation, as had 40 eyes (group B) in the control group. We compared the incidence, type, and degree of capsular opacity between A and B groups and also endothelial cell loss after surgery between the two groups. For insertion group A, the frequency of posterior capsular opacity was lower(7.3%), the duration to development was longer, and the energy required for Nd-Yag capsulotomy of PCO was less than for control group B (25%) (p=0.037). The endothelial cell count loss rate was not significantly different between the two groups (p=0.522). The capsular tension ring is associated with a significantly reduced incidence of posterior capsular opacity and is a safe procedure.

Breastfeeding and maternal HIV-1 disease progression and mortality.

To examine the association between breastfeeding and disease progression among HIV-infected women in Dar es Salaam, Tanzania. Cohort study design with Cox proportional hazards models. The relative risk of death comparing women who recently had been breastfeeding to those who were not breastfeeding was 0.47 (95% confidence interval, 0.18-1.20). Neither breastfeeding status nor the duration of exclusive or partial breastfeeding was associated with HIV-1 disease progression, represented by death or development of a low CD4 cell count, anemia or excessive weight loss, in multivariate analyses. These associations remained insignificant when women with relatively low and high CD4 cell counts were analyzed separately. There is insufficient evidence to support the hypothesis that breastfeeding is detrimental to the health of HIV-infected women.