Concurrent chemotherapy-radiotherapy compared with radiotherapy alone in locoregionally advanced nasopharyngeal carcinoma: progression-free survival analysis of a phase III randomized trial

PURPOSE

Nasopharyngeal carcinoma (NPC) is highly sensitive to both radiotherapy (RT) and chemotherapy. This randomized phase III trial compared concurrent cisplatin-RT (CRT) with RT alone in patients with locoregionally advanced NPC.

PATIENTS AND METHODS

Patients with Ho's N2 or N3 stage or N1 stage with nodal size > or = 4 cm were randomized to receive cisplatin 40 mg/m(2) weekly up to 8 weeks concurrently with radical RT (CRT) or RT alone. The primary end point was progression-free survival (PFS).

RESULTS

Three hundred fifty eligible patients were randomized. Baseline patient characteristics were comparable in both arms. There were significantly more toxicities, including mucositis, myelosuppression, and weight loss in the CRT arm. There were no treatment-related deaths in the CRT arm, and one patient died during treatment in the RT-alone arm. At a median follow-up of 2.71 years, the 2-year PFS was 76% in the CRT arm and 69% in the RT-alone arm (P =.10) with a hazards ratio of 1.367 (95% confidence interval [CI], 0.93 to 2.00). The treatment effect had a significant covariate interaction with tumor stage, and a subgroup analysis demonstrated a highly significant difference in favor of the CRT arm in Ho's stage T3 (P =.0075) with a hazards ratio of 2.328 (95% CI, 1.26 to 4.28). For T3 stage, the time to first distant failure was statistically significantly different in favor of the CRT arm (P =.016).

CONCLUSION

Concurrent CRT is well tolerated in patients with advanced NPC in endemic areas. Although PFS was not significantly different between the concurrent CRT arm and the RT-alone arm in the overall comparison, PFS was significantly prolonged in patients with advanced tumor and node stages.

Muscle dysmorphia. An underrecognized form of body dysmorphic disorder

In the course of several ongoing studies, the authors have encountered men and women who display a form of body dysmorphic disorder in which they become pathologically preoccupied with their degree of muscularity. This condition, which the authors have tentatively termed "muscle dysmorphia," may cause severe subjective distress, impaired social and occupational functioning, and abuse of anabolic steroids and other substances. Epidemiologic data suggest that muscle dysmorphia, though rarely recognized, may afflict substantial numbers of Americans. The authors summarize the features of muscle dysmorphia, present several case examples, and offer proposed diagnostic criteria that may be useful for subsequent research.

Epidural analgesia reduces postoperative myocardial infarction: a meta-analysis

Postoperative cardiac morbidity and mortality continue to pose considerable risks to surgical patients. Postoperative epidural analgesia is considered to have beneficial effects on cardiac outcomes. The use in high-risk cardiac patients remains controversial. No study has shown that postoperative epidural analgesia decreases postoperative myocardial infarction (PMI) or death. All studies are underpowered to show such a result, and the cost of conducting a large trial is prohibitive. We performed a metaanalysis to determine whether postoperative epidural analgesia continued for more than 24 h after surgery reduces PMI or in-hospital death. The available databases were searched for randomized controlled trials of epidural analgesia that was extended at least 24 h into the postoperative period. The search yielded 17 studies, of which 11 were randomized controlled trials comprising 1173 patients. Metaanalysis was conducted by using the fixed-effects model, calculating both an odds ratio and a rate difference. Postoperative epidural analgesia resulted in better analgesia for the first 24 h after surgery. The rate of PMI was 6.3%, with lower rates in the Epidural group (rate difference, -3.8%; 95% confidence interval [CI] -7.4%, -0.2%; P = 0.049). The frequency of in-hospital death was 3.3%, with no significant difference between Epidural and Nonepidural groups (rate difference, -1.3%; 95% CI, -3.8%, 1.2%, P = 0.091). Subgroup analysis of postoperative thoracic epidural analgesia showed a significant reduction in PMI in the Epidural group (rate difference, -5.3%; 95% CI, -9.9%, -0.7%; P = 0.04).

IMPLICATIONS

Postoperative epidural analgesia, especially thoracic epidural analgesia, continued for more than 24 h reduces postoperative myocardial infarctions.

Significant prognosticators after primary radiotherapy in 903 nondisseminated nasopharyngeal carcinoma evaluated by computer tomography

PURPOSE

To evaluate the significant prognosticators in nasopharyngeal carcinoma (NPC).

METHODS AND MATERIALS

From 1984 to 1989, 903 treatment-naive nondisseminated (MO) NPC were given primary radical radiotherapy to 60-62.5 Gy in 6 weeks. All patients had computed tomographic (CT) and endoscopic evaluation of the primary tumor. Potentially significant parameters (the patient's age and sex, the anatomical structures infiltrated by the primary lesion, the cervical nodal characteristics, the tumor histological subtypes, and various treatment variables were analyzed by both monovariate and multivariate methods for each of the five clinical endpoints: actuarial survival, disease-free survival, free from distant metastasis, free from local failure, and free from regional failure.

RESULTS

The significant prognosticators predicting for an increased risk of distant metastases and poorer survival included male sex, skull base and cranial nerve(s) involvement, advanced Ho's N level, and presence of fixed or partially fixed nodes or nodes contralateral to the side of the bulk of the nasopharyngeal primary. Advanced patient age led to significantly worse survival and poorer local tumor control. Local and regional failures were both increased by tumor infiltrating the skull base and/or the cranial nerves. In addition, regional failure was increased significantly by advancing Ho's N level. Parapharyngeal tumor involvement was the strongest independent prognosticator that determined distant metastasis and survival rates in the absence of the overriding prognosticators of skull base infiltration, cranial nerve(s) palsy, and cervical nodal metastasis.

CONCLUSIONS

The significant prognosticators are delineated after the advent of CT and these should form the foundation of the modern stage classification for NPC.

Impact of continuous positive airway pressure therapy on blood pressure in patients with obstructive sleep apnea hypopnea: a meta-analysis of randomized controlled trials

Patients with untreated obstructive sleep apnea hypopnea (OSAH) are predisposed to developing hypertension, and therapy with continuous positive airway pressure (CPAP) may reduce blood pressure (BP). The purpose of this study was to assess the impact of CPAP therapy on BP in patients with OSAH. We performed a comprehensive literature search up to July 2006 [Medline, PubMed, EMBASE, Cochrane Database of Systematic Reviews (CDSR), Cochrane controlled trials register (CCTR), and Database of Abstract and Reviews of Effect (DARE)] to identify clinical studies and systemic reviews that examined the impact of CPAP on BP. Studies were included if they (1) were randomized controlled trials with an appropriate control group, (2) included systolic and diastolic BP measurements before and after CPAP/control in patients with OSAH, and (3) contained adequate data to perform a meta-analysis. To calculate pooled results, studies were weighted by inverse variances, with either a fixed or a random effects model used depending on the presence of heterogeneity (assessed with Q test). Ten studies met our inclusion criteria (587 patients): three studies were crossover (149 patients) and seven were parallel in design. Seven studies (421 patients) used 24-h ambulatory BP and three used one-time measurements. Two studies were of patients with heart failure (41 patients). Overall, the effects of CPAP were modest and not statistically significant; CPAP (compared to control) reduced systolic BP (SBP) by 1.38 mmHg (95% CI: 3.6 to -0.88, p = 0.23) and diastolic BP (DBP) by 1.52 mmHg (CI: 3.1 to -0.07; p = 0.06). Six of the trials studied more severe OSAH (mean AHI > 30/h, 313 patients); in these six trials, CPAP reduced SBP by 3.03 mmHg (CI 6.7 to -0.61; p = 0.10) and DBP by 2.03 mmHg (CI: 4.1 to -0.002; p = 0.05). There was a trend for SBP reduction to be associated with CPAP compliance. In unselected patients with sleep apnea, CPAP has very modest effects on BP. However, we cannot exclude the possibility that certain subgroups of patients may have more robust responses-this may include patients with more severe OSAH or difficult-to-control hypertension. Future randomized controlled trials in this area should potentially concentrate on these subgroups of patients.

A patient education program to improve adherence rates with antituberculosis drug regimens

The design, logic, and results of a two-year health education study directed at improving rates of patient adherence to antituberculosis medical regimens are presented. An incentive scheme to reward positive health behaviors plus targeted educational counseling sessions was implemented in a randomized clinical controlled trial. The 205 subjects who participated in the study are categorized according to patients with active tuberculosis (n = 88) or preventive patients with no evidence of active disease (n = 117). Patients in each of these groups were randomly assigned to a special intervention (SI) group or a usual care (UC) control group and were followed monthly throughout their treatment program. While SI patients with active tuberculosis demonstrated higher levels of appointment-keeping behavior and mean percent of medication taken compared to UC patients, no statistically significant differences between the two groups were found. Preventive therapy patients assigned to the SI group, however, were significantly more likely than UC patients to remain in care during their 12-month regimen (64% vs 47%; p = .003). Furthermore, SI patients had significantly higher levels of adherence to their medical regimen compared to UC patients (68% vs 38%; p less than .001). These results demonstrate the positive effects of a structured health education program on the improvement of continuity of care and adherence behavior among patients with tuberculosis.

SEPT5_v2 is a parkin-binding protein

Mutations in parkin are associated with various inherited forms of Parkinson's disease (PD). Parkin is a ubiquitin ligase enzyme that catalyzes the covalent attachment of ubiquitin moieties onto substrate proteins destined for proteasomal degradation. The substrates of parkin-mediated ubiquitination have yet to be completely identified. Using a yeast two-hybrid screen, we isolated the septin, human SEPT5_v2 (also known as cell division control-related protein 2), as a putative parkin-binding protein. SEPT5_v2 is highly homologous to another septin, SEPT5, which was recently identified as a target for parkin-mediated ubiquitination. SEPT5_v2 binds to parkin at the amino terminus and in the ring finger domains. Several lines of evidence have validated the putative link between parkin and SEPT5_v2. Parkin co-precipitates with SEPT5_v2 from human substantia nigra lysates. Parkin ubiquitinates SEPT5_v2 in vitro, and both SEPT5_v1 and SEPT5_v2 accumulate in brains of patients with ARJP, suggesting that parkin is essential for the normal metabolism of these proteins. These findings suggest that an important relationship exists between parkin and septins.

Neuraxial block, death and serious cardiovascular morbidity in the POISE trial

BACKGROUND

This post hoc analysis aimed to determine whether neuraxial block was associated with a composite of cardiovascular death, non-fatal myocardial infarction (MI) and non-fatal cardiac arrest within 30 days of randomization in POISE trial patients.

METHODS

A total of 8351 non-cardiac surgical patients at high risk of cardiovascular complications were randomized to β-blocker or placebo. Neuraxial block was defined as spinal, lumbar or thoracic epidural anaesthesia. Logistic regression, with weighting using estimated propensity scores, was used to determine the association between neuraxial block and primary and secondary outcomes.

RESULTS

Neuraxial block was associated with an increased risk of the primary outcome [287 (7.3%) vs 229 (5.7%); odds ratio (OR), 1.24; 95% confidence interval (CI), 1.02-1.49; P=0.03] and MI [230 (5.9%) vs 177 (4.4%); OR, 1.32; 95% CI, 1.07-1.64; P=0.009] but not stroke [23 (0.6%) vs 32 (0.8%); OR, 0.76; 95% CI, 0.44-1.33; P=0.34], death [96 (2.5%) vs 111 (2.8%); OR, 0.87; 95% CI, 0.65-1.17; P=0.37] or clinically significant hypotension [522 (13.4%) vs 484 (12.1%); OR, 1.13; 95% CI, 0.99-1.30; P=0.08]. Thoracic epidural with general anaesthesia was associated with a worse primary outcome than general anaesthesia alone [86 (12.1%) vs 119 (5.4%); OR, 2.95; 95% CI, 2.00-4.35; P<0.001].

CONCLUSIONS

In patients at high risk of cardiovascular morbidity, neuraxial block was associated with an increased risk of adverse cardiovascular outcomes, which could be causal or because of residual confounding.

Co-association of parkin and alpha-synuclein

Parkin and alpha-synuclein are two proteins that are associated with the pathophysiology of Parkinson's disease (PD). Parkin is present in Lewy bodies and axonal spheroids in brains affected by PD, and mutations in parkin cause hereditary forms of Parkinsonism. Alpha-synuclein is a major component of Lewy bodies and is associated with rare cases of PD. We now show that parkin binds to alpha-synuclein, including conditions associated with alpha-synuclein aggregation. Parkin and alpha-synuclein complexes were observed in BE-M17 cells under basal conditions, in BE- M17 cells under oxidative conditions and in brains from control or PD donors. Double staining of PD brains shows parkin and alpha-synuclein co-localize to the same pathological structures (both Lewy bodies and axonal spheroids). These results suggest that parkin interacts with alpha-synuclein and could contribute to the pathophysiology of PD more generally than was previously considered.

Combining structural and chemical information at the nanometer scale by correlative transmission electron microscopy and atom probe tomography

In many cases, the three-dimensional reconstructions from atom probe tomography (APT) are not sufficiently accurate to resolve crystallographic features such as lattice planes, shear bands, stacking faults, dislocations or grain boundaries. Hence, correlative crystallographic characterization is required in addition to APT at the exact same location of the specimen. Also, for the site-specific preparation of APT tips containing regions of interest (e.g. grain boundaries) correlative electron microscopy is often inevitable. Here we present a versatile experimental setup that enables performing correlative focused ion beam milling, transmission electron microscopy (TEM), and APT under optimized characterization conditions. The setup was designed for high throughput, robustness and practicability. We demonstrate that atom probe tips can be characterized by TEM in the same way as a standard TEM sample. In particular, the use of scanning nanobeam diffraction provides valuable complementary crystallographic information when being performed on atom probe tips. This technique enables the measurement of orientation and phase maps as known from electron backscattering diffraction with a spatial resolution down to one nanometer.

Cellular and molecular characterization of a murine non-union model

PURPOSE

We have developed a method to study the molecular and cellular events underlying delayed skeletal repair in a model that utilizes distraction osteogenesis.

METHODS

The clinical states of delayed union and non-union were reproduced in this murine model by altering distraction parameters such as the inclusion and exclusion of a latency phase and variations in the rate and rhythm of distraction. Radiographic, cellular, and molecular analyses were performed on the distraction tissues.

RESULTS

Eliminating the latency period delayed bony union, but did not appreciably alter the extent of platelet endothelial cell adhesion marker (PECAM) immunostaining. Following elimination of a latency phase and a threefold increase in the rate of distraction, there was a further delay in bone regeneration and a higher rate of non-union (60%). Instead of bone, the distraction gap was comprised of adipose or fibrous tissue. Once again, despite the rigorous distraction protocol, we detected equivalent PECAM staining within the distraction gap. In a minority of cases, cartilage and osseous tissues occupied the distraction gap likely by a prolonged process of endochondral ossification.

CONCLUSIONS

Here, we have altered the mechanical environment in such a way to reproducibly create delays in skeletal regeneration. These delays in skeletal tissue regeneration appear to develop even in the presence of endothelial cells, which suggests that mechanisms other than a disruption to the vascular network can account for some cases of non-union.

Atomic-scale quantification of grain boundary segregation in nanocrystalline material

Grain boundary segregation leads to nanoscale chemical variations that can alter a material's performance by orders of magnitude (e.g., embrittlement). To understand this phenomenon, a large number of grain boundaries must be characterized in terms of both their five crystallographic interface parameters and their atomic-scale chemical composition. We demonstrate how this can be achieved using an approach that combines the accuracy of structural characterization in transmission electron microscopy with the 3D chemical sensitivity of atom probe tomography. We find a linear trend between carbon segregation and the misorientation angle ω for low-angle grain boundaries in ferrite, which indicates that ω is the most influential crystallographic parameter in this regime. However, there are significant deviations from this linear trend indicating an additional strong influence of other crystallographic parameters (grain boundary plane, rotation axis). For high-angle grain boundaries, no general trend between carbon excess and ω is observed; i.e., the grain boundary plane and rotation axis have an even higher influence on the segregation behavior in this regime. Slight deviations from special grain boundary configurations are shown to lead to unexpectedly high levels of segregation.

Characterization of glucose-specific catabolite repression-resistant mutants of Bacillus subtilis: identification of a novel hexose:H+ symporter

Insertional mutagenesis was conducted on Bacillus subtilis cells to screen for mutants resistant to catabolite repression. Three classes of mutants that were resistant to glucose-promoted but not mannitol-promoted catabolite repression were identified. Cloning and sequencing of the mutated genes revealed that the mutations occurred in the structural genes for (i) enzyme II of the phosphoenolpyruvate-glucose phosphotransferase (PtsG), (ii) antiterminator GlcT, which controls PtsG synthesis, and (iii) a previously uncharacterized carrier of the major facilitator superfamily, which we have designated GlcP. The last protein exhibits greatest sequence similarity to the fucose:H+ symporter of Escherichia coli and the glucose/galactose:H+ symporter of Brucella abortus. In a wild-type B. subtilis genetic background, the glcP::Tn10 mutation (i) partially but specifically relieved glucose- and sucrose-promoted catabolite repression, (ii) reduced the growth rate in minimal glucose medium, and (iii) reduced rates of [14C]glucose and [14C]methyl alpha-glucoside uptake. In a delta pts genetic background no phenotype was observed, suggesting that expression of the glcP gene required a functional phosphotransferase system. When overproduced in a delta pts mutant of E. coli, GlcP could be shown to specifically transport glucose, mannose, 2-deoxyglucose and methyl alpha-glucoside with low micromolar affinities. Accumulation of the nonmetabolizable glucose analogs was demonstrated, and inhibitor studies suggested a dependency on the proton motive force. We conclude that B. subtilis possesses at least two distinct routes of glucose entry, both of which contribute to the phenomenon of catabolite repression.

Parkin is metabolized by the ubiquitin/proteosome system

Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism. Immunostaining of substantia nigra sections from sporadic Parkinson's disease (PD) cases shows that Parkin accumulates in axonal spheroids and in some Lewy bodies. Because ubiquitin is a major component of Lewy bodies and axonal spheroids, we investigated whether Parkin is metabolized via the ubiquitin/proteosomal pathway. Treatment of BE-M17 neuroblastoma cells with the proteosomal inhibitor, MG132, produced a band corresponding to di-ubiquitinated Parkin that was apparent by immunoblot using two different anti-Parkin antibodies. This higher mol. wt band also co-immunoprecipitated with Parkin. These data suggest that Parkin plays a role in the pathophysiology of sporadic PD, and that Parkin is a substrate for ubiquitination that is degraded by the proteosomal complex.

Prevalence and correlates of community re-entry challenges faced by HIV-infected male prisoners in Malaysia

HIV-infected prisoners face an inordinate number of community re-entry challenges. In 2007, 102 HIV-infected prisoners in Malaysia were surveyed anonymously within six months prior to release to assess the prevalence and correlates of community re-entry challenges. Staying out of prison (60.8%), remaining off drugs (39.2%), finding employment (35.3%) and obtaining HIV care (32.4%) were the re-entry challenges reported most frequently. Global stigma, negative self-image and public attitudes-related stigma were independently associated with challenges to obtaining HIV care. In multivariate analyses, those with previous incarcerations (adjusted odds ratio [AOR], 3.2; 95% confidence interval [CI], 1.4-7.6), higher HIV-related symptoms (AOR, 2.0; 95% CI, 1.0-4.1) and higher public attitudes-related stigma (AOR, 2.5; 95% CI, 1.2-5.1) had a significantly higher likelihood of identifying more re-entry challenges. Targeted interventions, such as effective drug treatment, HIV care and public awareness campaigns, are crucial for stemming the HIV epidemic and improving health outcomes among HIV-infected prisoners in Malaysia.

Afterloading radiotherapy for local persistence of nasopharyngeal carcinoma

71 patients suffering from local persistence of nasopharyngeal carcinoma after primary external radiotherapy were treated by afterloading intracavitary 192Ir. 66 (93.0%) had a complete response as evidenced by fibreoptic nasopharyngoscope examination and biopsy 4 weeks after the treatment. Significant prognosticators were studied by both monovariate and multivariate analysis. The early overall clinical stage at first presentation predicted a favourable survival. Local tumour control was adversely affected by advanced T-stage at first presentation, and by using a single 192Ir source, unilaterally applied to treat only one side of the nasopharynx. The intracavitary treatment was tolerated well and treatment complications were confined to the nasopharynx: chronic radiation ulceration (five patients) and diffuse telangiectasia (three patients).

Atomic scale investigation of non-equilibrium segregation of boron in a quenched Mo-free martensitic steel

B-added low carbon steels exhibit excellent hardenability. The reason has been frequently attributed to B segregation at prior austenite grain boundaries, which prevents the austenite to ferrite transformation and favors the formation of martensite. The segregation behavior of B at prior austenite grain boundaries is strongly influenced by processing conditions such as austenitization temperatures and cooling rates and by alloying elements such as Mo, Cr, and Nb. Here an local electrode atom probe was employed to investigate the segregation behavior of B and other alloying elements (C, Mn, Si, and Cr) in a Cr-added Mo-free martensitic steel. Similar to our previous results on a Mo-added steel, we found that in both steels B is segregated at prior austenite grain boundaries with similar excess values, whereas B is neither detected in the martensitic matrix nor at martensite-martensite boundaries at the given cooling rate of 30K/s. These results are in agreement with the literature reporting that Cr has the same effect on hardenability of steels as Mo in the case of high cooling rates. The absence of B at martensite-martensite boundaries suggests that B segregates to prior austenite grain boundaries via a non-equilibrium mechanism. Segregation of C at all boundaries such as prior austenite grain boundaries and martensite-martensite boundaries may occur by an equilibrium mechanism.