Selective laser trabeculoplasty: Does energy dosage predict response?

Background:

Selective laser trabeculoplasty (SLT) is a widely used treatment for open angle glaucoma, producing sustained reductions of intraocular pressure (IOP). The aim of this study was to evaluate the long-term relationship between SLT energy dosage and IOP reduction.

Materials and Methods:

A retrospective review was performed for patients receiving primary SLT therapy, with inclusion of subjects treated with 360° of SLT. Energy settings were collected upon treatment and IOP was collected at baseline up to 36 months. Pearson's correlation coefficient was used to determine whether there was a significant correlation between SLT energy and IOP reduction at all time points. Kaplan-Meier analysis with log-rank test was performed to determine the differences in IOP reduction ≥20% from baseline among those treated with low (<85 mJ), medium (85-105 mJ), and high (>105 mJ) energy SLT.

Results:

A total of 104 eyes (75 patients) were included. The mean total SLT energy was 93.73 mJ (standard deviation (SD) = 21.83 mJ, range: 34.4-122 mJ). A significant positive correlation (P ≤ 0.05) between the amount of energy delivered and IOP reduction was found at all time points. Log-rank test showed a significant difference in IOP reduction ≥20% from baseline between the three energy groups, with low energy patients experiencing failure at an earlier time (P = 0.05).

Conclusions:

Within the range of total energy examined, there is a positive correlation between total energy used and amount of pressure reduction achieved at up to 3 years of follow-up. This may be useful in determining the optimal energy dosage for maximum effect for patients receiving SLT.

Drug-induced reactivation of apoptosis abrogates HIV-1 infection

HIV-1 blocks apoptosis, programmed cell death, an innate defense of cells against viral invasion. However, apoptosis can be selectively reactivated in HIV-infected cells by chemical agents that interfere with HIV-1 gene expression. We studied two globally used medicines, the topical antifungal ciclopirox and the iron chelator deferiprone, for their effect on apoptosis in HIV-infected H9 cells and in peripheral blood mononuclear cells infected with clinical HIV-1 isolates. Both medicines activated apoptosis preferentially in HIV-infected cells, suggesting that the drugs mediate escape from the viral suppression of defensive apoptosis. In infected H9 cells, ciclopirox and deferiprone enhanced mitochondrial membrane depolarization, initiating the intrinsic pathway of apoptosis to execution, as evidenced by caspase-3 activation, poly(ADP-ribose) polymerase proteolysis, DNA degradation, and apoptotic cell morphology. In isolate-infected peripheral blood mononuclear cells, ciclopirox collapsed HIV-1 production to the limit of viral protein and RNA detection. Despite prolonged monotherapy, ciclopirox did not elicit breakthrough. No viral re-emergence was observed even 12 weeks after drug cessation, suggesting elimination of the proviral reservoir. Tests in mice predictive for cytotoxicity to human epithelia did not detect tissue damage or activation of apoptosis at a ciclopirox concentration that exceeded by orders of magnitude the concentration causing death of infected cells. We infer that ciclopirox and deferiprone act via therapeutic reclamation of apoptotic proficiency (TRAP) in HIV-infected cells and trigger their preferential elimination. Perturbations in viral protein expression suggest that the antiretroviral activity of both drugs stems from their ability to inhibit hydroxylation of cellular proteins essential for apoptosis and for viral infection, exemplified by eIF5A. Our findings identify ciclopirox and deferiprone as prototypes of selectively cytocidal antivirals that eliminate viral infection by destroying infected cells. A drug-based drug discovery program, based on these compounds, is warranted to determine the potential of such agents in clinical trials of HIV-infected patients.

White matter impairment in the speech network of individuals with autism spectrum disorder

Impairments in language and communication are core features of Autism Spectrum Disorder (ASD), and a substantial percentage of children with ASD do not develop speech. ASD is often characterized as a disorder of brain connectivity, and a number of studies have identified white matter impairments in affected individuals. The current study investigated white matter integrity in the speech network of high-functioning adults with ASD. Diffusion tensor imaging (DTI) scans were collected from 18 participants with ASD and 18 neurotypical participants. Probabilistic tractography was used to estimate the connection strength between ventral premotor cortex (vPMC), a cortical region responsible for speech motor planning, and five other cortical regions in the network of areas involved in speech production. We found a weaker connection between the left vPMC and the supplementary motor area in the ASD group. This pathway has been hypothesized to underlie the initiation of speech motor programs. Our results indicate that a key pathway in the speech production network is impaired in ASD, and that this impairment can occur even in the presence of normal language abilities. Therapies that result in normalization of this pathway may hold particular promise for improving speech output in ASD.

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We used diffusion tensor imaging to measure white matter (WM) tracts in autism.

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Autistic participants were high-functioning individuals with normal language skills.

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WM between left supplementary motor and premotor areas is impaired in autism.

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This tract is believed to be involved in the initiation of speech articulation.

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Speech production may be impaired in the absence of language deficits in autism.

SU-E-T-412: Can Cyberknife SBRT Be an Alternative to Brachytherapy for Cervical Cancer Treatment?

PURPOSE

To investigate the effectiveness of stereotactic body radiation therapy (SBRT) with Cyberknife for treatment of squamous cell carcinoma (SCCa) of cervix that are commonly treated with brachytherapy.

METHODS

SCCa of cervix is routinely treated with external beam radiation therapy (EBRT) followed by brachytherapy. Common practice is to use high-dose- rate (HDR) brachytherapy, mainly with Ir-192; however, low-dose-rate (LDR) brachytherapy with Cs-137 is also used. Three of our patients with cervical SCCa who were chosen to have LDR brachytherapy (Cs-137 with tandem and ovoids) could not tolerate the prolonged treatment or applicator placement. All these patients previously received 45Gy (1.8Gy/fratction) from EBRT and well tolerated. Planned LDR treatment dose and time were for patient-1: 42.63Gy in 73.5hr, patient-2: 42.34Gy in 73hr, patient-3: 41.76Gy in 72hr. Delivered LDR dose and time were: 3.75Gy in 6.5hr, OGy in Ohr, and 17.3Gy in 19.8hr, for patient-1, -2 and -3, respectively. Two of the three patients tolerated LDR treatment partially; the second patient could not tolerate the applicator, which required immediate removal after placement. Treatments were completed with Cyberknife SBRT (CK-SBRT)doses of 25Gy, 15Gy and 25Gy for patient-1, -2 and -3, respectively; all had 5Gy/fraction and 3fractions/week. Prescriptions were at 80% isododelines; CTV coverages were 96.6%, 99.9% and 100% for patient-1, -2 and -3, respectively.

RESULTS

Till their last follow-up in February 2012, all three patients were doing fine clinically without any evidence of disease; none of these patients had any complications that could be related to CK-SBRT.

CONCLUSIONS

Appears that CK-SBRT can be a viable treatment alternative to brachytherapy. CK-SBRT may also be more appealing to patients and physicians for a variety of reasons such as out-patient procedure, shorter treatment time, no need for operating room, and no need for applicator insertion and tolerance. However, extensive clinical study is warranted in this regard.

SU-E-T-422: Lung SBRT Using Cyberknife: Technique and Treatment Outcome

PURPOSE

At East Carolina University, we have been treating primary and secondary lung cancers with Cyberknife stereotactic body radiotherapy (CK- SBRT) since February 2009. Till October 2011, we have treated a total of 79 patients (83 sites). In this study, we present our experience in CK-SBRT and clinical outcome of the treated patients.

METHODS

Of the 79 patients, 43 were female; age of the whole patient population ranged 33.2-89.7yrs (median=73.2yrs). Patients treated for primary lung cancer (n=57) had severe chronic obstructive pulmonary disease (COPD) and were not surgical candidates. Cyberknife robotic system with tracking techniques (Synchrony=52, XsiteLung=22, XsightSpine=5) were used. Majority of the patient (n=52) had multiple gold fiducials placed (1-6 placed; 1-4 tracked per patient) either percutaneously or bronchoscopically. CT images were used for dosimetric planning, by medical physicists, using Cyberknife MultiPlan software. Prescription doses were 25Gy-55Gy in 3-5 fractions (mean=48.2Gy, median=50Gy); doses were prescribed mainly to 80% isodoseline (range=75-96%, mean=81.4%). PTV margin varied from 0-7mm (mean±SD=3.2±1.4mm), based on the tumor locations; breathing patterns and cancer type. Dosimetric coverage of GTV and PTV were (mean±SD): 97.8±5% and 94.7±6.9%, respectively. The treatment response was assessed using either a CT or a PET scan or both.

RESULTS

The median follow up was 13.1months (range 0.3-31.9 months). Overall response rate was 98.8% (CR=73.5%). Local failure free survival at one year was 84% for primary (n=57), 76% for recurrent (n=16) lung cancer and 100% for metastatic (n=10) tumors. The toxicity rate was low with one patient reported to have chest wall pain and one patient developed grade 3-4 radiation pneumonitis.

CONCLUSIONS

In most of the cases tight PTV margins were used. Since the prescriptions were at 80% isodeose line with more than 94% PTV coverage, the treatment outcome appeared reasonable. Further study relating PTV margin, dosimetric coverage, and treatment outcome is in progress.

Human immunodeficiency virus infection in advanced maternal age gravidas

Our study compares perinatal outcomes among HIV(+) versus HIV(-) advanced maternal aged (AMA) women. A retrospective cohort study of AMA deliveries from 2000 to 2009 was performed. HIV(+) (group A) women were compared to temporally matched HIV(-) (group B) women. Demographics, medical comorbidities, HIV treatment, and delivery data were collected. SAS was used for data analysis with p<0.05 considered significant. Seventy-one patients per study group were reviewed; for group A, the mean CD4 count near delivery was 507±363; 75% (34/45) had viral load ≤400 in the third trimester and 58% were on a protease inhibitor regimen. HIV(+) women had significantly higher preterm delivery (PTD) <37 weeks (A: 40.85%, B: 16.90%, p=0.0016). Logistic regression performed revealed that the odds of PTD was 2.83 (CI 1.22-6.54) for HIV(+) and 4.02 (CI 1.27-12.72) for drug use independent of other factors. The pathophysiology of PTD among HIV(+) AMA women warrants prospective examination to better define the causal relationship.

Self-reported non-adherence to immune-suppressant therapy in liver transplant recipients: demographic, interpersonal, and intrapersonal factors

Adherence to immune suppressants and follow-up care regimen is important in achieving optimal long-term outcomes after organ transplantation. To identify patients most at risk for non-adherence, this cross-sectional, descriptive study explores the prevalence and correlates of non-adherence to immune-suppressant therapy among liver recipients. Anonymous questionnaires mailed consisted of the domains: (i) adherence barriers to immune suppressants, (ii) immune suppressants knowledge, (iii) demographics, (iv) social support, (v) medical co-morbidities, and (vi) healthcare locus of control and other beliefs. Overall response was 49% (281/572). Data analyzed for those transplanted within 10 yr of study reveal 50% (119/237) recipients or 9.2/100 person years reporting non-adherence. Non-adherence was reported highest in the 2-5 yr post-transplant phase (69/123, 56%). The highest immune-suppressant non-adherence rates were in recipients who are: divorced (26/34, 76%, p=0.0093), have a history of substance or alcohol use (42/69, 61%, p=0.0354), have mental health needs (50/84, 60%, p=0.0336), those who missed clinic appointments (25/30, 83%, p<0.0001), and did not maintain medication logs (71/122, 58%, p=0.0168). Respondents who were non-adherent with physician appointments were more than four and a half times as likely (OR 4.7, 95% CI 1.5-14.7, p=0.008) to be non-adherent with immune suppressants. In conclusion, half of our respondents report non-adherence to immune suppressants. Factors identified may assist clinicians to gauge patients' non-adherence risk and target resources.

Imputing supertrees and supernetworks from quartets

Inferring species phylogenies is an important part of understanding molecular evolution. Even so, it is well known that an accurate phylogenetic tree reconstruction for a single gene does not always necessarily correspond to the species phylogeny. One commonly accepted strategy to cope with this problem is to sequence many genes; the way in which to analyze the resulting collection of genes is somewhat more contentious. Supermatrix and supertree methods can be used, although these can suppress conflicts arising from true differences in the gene trees caused by processes such as lineage sorting, horizontal gene transfer, or gene duplication and loss. In 2004, Huson et al. (IEEE/ACM Trans. Comput. Biol. Bioinformatics 1:151-158) presented the Z-closure method that can circumvent this problem by generating a supernetwork as opposed to a supertree. Here we present an alternative way for generating supernetworks called Q-imputation. In particular, we describe a method that uses quartet information to add missing taxa into gene trees. The resulting trees are subsequently used to generate consensus networks, networks that generalize strict and majority-rule consensus trees. Through simulations and application to real data sets, we compare Q-imputation to the matrix representation with parsimony (MRP) supertree method and Z-closure, and demonstrate that it provides a useful complementary tool.

Hemorrhagic complications of external ventricular drainage

OBJECTIVE

Despite the widespread use of external ventricular drainage (EVD), the frequency of associated hemorrhagic complications remains unclear. This retrospective study examined the frequency of hemorrhagic complications of EVD and attempted to discern associated risk factors.

METHODS

Treatment records from 160 patients admitted during a 2.5-year period who required EVD placement were reviewed. Indications for placement of EVD included acute complications of cerebrovascular disease (n = 94), traumatic brain injury (n = 36), primary hydrocephalus (n = 16), and tumor (n = 14). Patients received either a 3.0 or 2.5-mm outer diameter ventricular catheter (n = 82 and 78, respectively). Postinsertion computed tomographic scans were obtained within 24 hours on all patients and were analyzed for any new hemorrhage related to the ventricular catheter. Patient age, sex, catheter type, and dimensions of hemorrhage were also analyzed.

RESULTS

The incidence of EVD-related hemorrhage was 33 +/- 0.04%. However, the incidence of detectable change in the clinical neurological examination was 2.5%. A significant proportion of EVD-related hemorrhages were small (<4 cm), punctate, intraparenchymal hematomas. Patients with cerebrovascular disease exhibited an increased incidence (39%) of hemorrhage. The mean volume of intraparenchymal hemorrhage was larger in patients who received the 2.5-mm ventricular catheter, as well as those admitted for cerebrovascular disease.

CONCLUSION

Hemorrhagic complications of EVD placement are more common than previously suspected. Admitting diagnosis seems to have an effect on the development of an associated hemorrhage and its size. Catheter gauge has an effect on hematoma volume. Most of the hemorrhages seen on postinsertion computed tomographic scans do not cause detectable changes in the clinical examination.

Effect of pregnancy and human immunodeficiency virus infection on intracellular interleukin-2 production patterns

Human immunodeficiency virus type 1 (HIV-1) infection decreases the production of interleukin-2 (IL-2) from CD4+ and CD8+ T cells. Recombinant IL-2 (rIl-2) has been given to HIV-infected individuals to generate significant increases in CD4+ T-cell counts. There are limited data regarding the effects of pregnancy and HIV infection on IL-2 production in humans. To investigate the effects of human pregnancy, HIV infection, and HIV therapy on IL-2 production, we evaluated 61 women. Intracellular IL-2 production by CD4+ T cells from nonpregnant HIV-infected women was significantly lower than in that in uninfected women (45% +/- 8% versus 52% +/- 8%, P = 0.04). In contrast, there was no difference in levels of intracellular IL-2 production between HIV-infected and uninfected pregnant women. These observations suggest that pregnancy may down-regulate IL-2 production regardless of HIV infection status. Future studies should evaluate IL-2 production patterns in larger cohorts of women so that the physiological significance of IL-2 down-regulation in pregnancy can be further evaluated. This information is essential to assess the possible use of IL-2 supplementation therapy as a means of enhancing immune responses among HIV-infected pregnant women.

Procollagen-derived biomarkers in malignant ascites of ovarian cancer. Independent prognosticators for progression-free interval and survival

OBJECTIVE

Matrix formation is a hallmark of solid tumor biology. Circulating antigens of structural matrix proteins should reflect this fact, yet are subject to systemic variables. We propose that if measured regionally, in a cancer-induced extravascular fluid pool such as malignant ascites of ovarian cancer, the same antigens retain their conceptual advantage as surrogate markers for tumor biology.

METHODS

In malignant ascites obtained at staging laparatomy of 35 women with ovarian cancer, the protein-normalized levels of the C-terminal propeptide of procollagen type I (pnPICP) and the N-terminal propeptide of procollagen type III (pnPIIINP) were determined. Using univariate and multivariate analysis, we examined these parameters, their (pnPIIINP/pnPICP) quotient, and clinical criteria (FIGO stage, age, residual tumor, histology, and tumor grade) for impact on progression-free interval and survival.

RESULTS

The absolute level of pnPIIINP was the single most powerful independent factor impacting on survival, its P value being distinctly below (P = 0.0005 vs 0.003) and its risk ratio distinctly above (15 vs 2.5) residual tumor after debulking surgery. The relative level of pnPIIINP, i.e. (pnPIIINP / pnPICP), impacted on the likelihood of recurrence even more than residual tumor. By Kaplan-Meier analysis, cutoff values for the absolute or relative pnPIIINP level significantly discriminated patients with shortened survival or progression-free interval, respectively.

CONCLUSIONS

Since malignant ovarian epithelium itself forms collagen type III, and since collagen type III is a solid-phase regulator of angiogenesis, we propose that ascitic pnPIIINP is a fluid-phase indicator for angiogenic activity in ovarian cancer and thus represents a tumor virulence index.

Genomic regions controlling vernalization and photoperiod responses in oat

Oat genotypes vary for photoperiod and vernalization responses. Vernalization often promotes earlier flowering in fall-sown but not spring-sown cultivars. Longer photoperiods also promote earlier flowering, and the response to longer photoperiods tends to be greater in cultivars from higher latitudes. To investigate the genetic basis of photoperiod and vernalization responses in oat, we mapped QTLs for flowering time under four combinations of photoperiod and vernalization treatments in the Ogle x TAM O-301 mapping population in growth chambers. We also mapped QTLs for flowering time in early spring and late-spring field plantings to determine the genetic basis of response to early spring planting in oat. Three major flowering-time QTLs (on linkage groups OT8, OT31 and OT32) were detected in most conditions. QTLs with smaller effects on flowering were less-consistently observed among treatments. Both vernalization-sensitive and insensitive QTLs were discovered. Longer photoperiod or vernalization alone tended to decrease the effects of flowering-time QTLs. Applied together, longer photoperiod and vernalization interacted synergistically, often on the same genomic regions. Earlier spring planting conferred an attenuated vernalization treatment on seeds. The major flowering-time QTLs mapped in this study matched those mapped previously in the Kanota x Ogle oat mapping population. Between these two studies, we found a concordance of flowering-time QTLs, segregation distortion, and complex genetic linkages. These effects may all be related to chromosomal rearrangements in hexaploid oat. Comparative mapping between oat and other grasses will facilitate molecular analysis of vernalization response in oat.

Rates of evolution in ancient DNA from Adélie penguins

Well-preserved subfossil bones of Adélie penguins, Pygoscelis adeliae, underlie existing and abandoned nesting colonies in Antarctica. These bones, dating back to more than 7000 years before the present, harbor some of the best-preserved ancient DNA yet discovered. From 96 radiocarbon-aged bones, we report large numbers of mitochondrial haplotypes, some of which appear to be extinct, given the 380 living birds sampled. We demonstrate DNA sequence evolution through time and estimate the rate of evolution of the hypervariable region I using a Markov chain Monte Carlo integration and a least-squares regression analysis. Our calculated rates of evolution are approximately two to seven times higher than previous indirect phylogenetic estimates.

Vitamin profile of 563 gravidas during trimesters of pregnancy

OBJECTIVE

Gestation imposes metabolic stress on the mother which heightens as pregnancy progresses. The need for quantifying circulating vitamins is important for identifying pitfalls in metabolic imbalance and nutritional status. For this reason we wanted to analyze blood vitamin concentrations of B12, thiamin, biotin, pantothenate, B6, niacin, riboflavin, folate, vitamins A, C, E and total carotenes to determine if imbalances occur during the trimesters of pregnancy.

METHODS

We randomly selected 563 gravidas who volunteered for this study from the obstetrical clinic of New Jersey Medical School; 132 were in 1st trimester, 198 were in 2nd trimester, and 233 were in 3rd trimester. All were healthy, taking a good diet and supplemented with vitamins. Blood, from an antecubital vein, was analyzed for thiamin, biotin, B12, B6, pantothenate, riboflavin, nicotinate, folates, vitamins A, E, C and total carotenes. Gravidas were classified as being normovitaminemic, hypervitaminemic or hypovitaminemic compared with blood vitamins seen in healthy non-pregnant, non-vitamin supplemented women.

RESULT

Hypervitaminemic levels of folate, biotin, pantothenate and riboflavin were found during any trimester of pregnancy due to vitamin supplementation. Despite the vitamin supplementation, a high percent of vitamin A, B6, niacin. thiamin and B 12 hypovitaminemia was noted during pregnancy trimesters. An especially high percentage of niacin deficiency was seen during the 1st trimester; it worsened in later trimesters; B12 deficits increased during the late trimesters. Combination deficits of niacin, thiamin, vitamins A, B6, B12 were noted in each of the trimesters.

CONCLUSIONS

Despite vitamin supplementation, a vitamin profile of pregnancy indicates that vitamin deficits exist during the trimesters. Also, combination hypovitaminemias of deficient vitamins were noted; this indicates that a vitamin deficit during pregnancy does not occur in isolation.

Antiretroviral resistance mutations among pregnant human immunodeficiency virus type 1-infected women and their newborns in the United States: vertical transmission and clades

To assess the impact of antiretroviral resistance on perinatal transmission prevention efforts, human immunodeficiency virus type 1 (HIV-1) genotypic resistance testing was done for 220 HIV-1-infected, zidovudine (AZT)-exposed pregnant women and 24 of their infected infants. The women were prospectively enrolled in 4 US cities in 1991-1997. Phylogenetic and sequencing analyses revealed 5 women with non-clade B infections traced to western African origins. AZT-associated mutations were detected in 17.3% of pregnant women, whereas genotypic resistance to nonnucleoside reverse-transcriptase inhibitors and protease inhibitors was infrequent. No significant association was detected between perinatal transmission and the presence of either AZT or nucleoside reverse-transcriptase inhibitor resistance-associated mutations. AZT resistance mutations were detected in 2 (8.3%) neonatal samples, but the mutation pattern was not identical to the mother's. Although no effect of viral resistance on mother-infant transmission was demonstrated, the advent of more-potent drug classes and the potential for the rapid emergence of resistance warrant prospective surveillance.

Males' evolutionary responses to experimental removal of sexual selection

We evaluated the influence of pre- and post-copulatory sexual selection upon male reproductive traits in a naturally promiscuous species, Drosophila melanogaster. Sexual selection was removed in two replicate populations through enforced monogamous mating with random mate assignment or retained in polyandrous controls. Monogamous mating eliminates all opportunities for mate competition, mate discrimination, sperm competition, cryptic female choice and, hence, sexual conflict. Levels of divergence between lines in sperm production and male fitness traits were quantified after 38-81 generations of selection. Three a priori predictions were tested: (i) male investment in spermatogenesis will be lower in monogamy-line males due to the absence of sperm competition selection, (ii) due to the evolution of increased male benevolence, the fitness of females paired with monogamy-line males will be higher than that of females paired with control-line males, and (iii) monogamy-line males will exhibit decreased competitive reproductive success relative to control-line males. The first two predictions were supported, whereas the third prediction was not. Monogamy males evolved a smaller body size and the size of their testes and the number of sperm within the testes were disproportionately further reduced. In contrast, the fitness of monogamous males (and their mates) was greater when reproducing in a non-competitive context: females mated once with monogamous males produced offspring at a faster rate and produced a greater total number of surviving progeny than did females mated to control males. The results indicate that sexual selection favours the production of increased numbers of sperm in D. melanogaster and that sexual selection favours some male traits conferring a direct cost to the fecundity of females.