Completion lymph node dissection for merkel cell carcinoma

BACKGROUND

Sentinel lymph node biopsy (SLNB) is widely used for Merkel cell carcinoma (MCC), however in SLNB positive MCC the role of completion lymph node dissection (CLND) with or without adjuvant radiation therapy is unclear.

OBJECTIVE

Our goal was to determine the impact of CLND and adjuvant radiation therapy on survival in SLNB positive MCC.

MATERIALS AND METHODS

We examined 447 patients with MCC with a positive SLNB in the National Cancer Data Base from 2012 to 2015. We compared patients who underwent CLND versus observation with or without adjuvant radiation.

RESULTS

Compared with CLND and adjuvant radiation (reference) treatment with observation (HR 3.54, CI 1.36-9.18) or CLND alone (HR 2.54, CI 1.03-6.27) were associated with worse overall survival after adjusting for clinicopathologic differences. In contrast treatment with adjuvant radiation alone without CLND was not associated with worse overall survival (HR 1.70, CI 0.74-3.92) compared with CLND and adjuvant radiation (reference).

CONCLUSIONS

In SLNB positive MCC, CLND alone is associated with worse survival compared with treatment with adjuvant radiation or both CLND and adjuvant radiation.

Effect of processing delay on bifurcation delay in a network of slow-fast oscillators

Bifurcation delay or slow passage effect occurs in dynamical systems with slow-fast time-varying parameters. In this work, we report the impact of processing delay on bifurcation delay in a network of locally coupled slow-fast systems with self-feedback delay. We report that the network exhibits coexisting coherent (synchronized) and incoherent (desynchronized) states among the oscillators as a function of various parameters like self-feedback delay, processing delay, and amplitude of the external current. In particular, we show the decrease of the synchronized region (control of synchronization) for (i) a fixed value of processing delay with varying self-feedback delay and (ii) fixed self-feedback delay with increasing processing delay. In contrast, we observe the increase of the synchronized region (control of desynchronization) for fixed processing delay and self-feedback delay while varying the amplitude of the external current. Finally, we have also analyzed the effect of processing delay on bifurcation delay with the presence of noise and we report that the inhomogeneity in the additional noise does not affect the asymmetry in a bifurcation delay.

Genotoxic effects of tobacco use in residents of hilly areas and foot hills of Western Ghats, Southern India

Smoking and smokeless tobacco consumption is a significant risk factor that provokes genetic alterations. The present investigation was to evaluate the biomarkers of genotoxicity including micronucleus (MN), chromosome aberrations (CA) and DNA strand breaks among tobacco consumers and control individuals residing in hilly areas of Western Ghats, Tamilnadu, South India. This study included 268 tobacco consumers with equal number of controls. The tobacco consumers were divided into Group I (<10 years of tobacco consumption with an age range from 15 to 35 years) and group II (>10 years consumption above 35 years of age). Chromosome aberration (CA) and comet assay were performed using blood and micronucleus assay from exfoliated buccal epithelial cells obtained from tobacco consumers and controls. Elevated levels of CA were found in group II (Chromatid type: 2.39 ± 1.13 and chromosome type: 1.44 ± 1.24) exposed subjects, high micronucleus and DNA damage (TL:4.48 ± 1.24 and TM:3.40 ± 1.58) levels were significantly (p < 0.05) observed in both smoking and smokeless tobacco consumers when comparison with group I and controls. This study also observed a lack of awareness among the tobacco consumers about the harmful health effects of tobacco. Tobacco consumption contributes to the significant alteration in genetic materials. In addition, a high rate of spontaneous abortion was also seen in the studied population.

A mid-treatment break and reassessment maintains tumor control and reduces toxicity in patients with hepatocellular carcinoma treated with stereotactic body radiation therapy

BACKGROUND AND PURPOSE

Patients with hepatocellular carcinoma (HCC) commonly have underlying liver dysfunction with variable tolerance to liver stereotactic body radiation therapy (SBRT). We hypothesized that insertion of a 1-month mid-treatment break would allow us to adapt treatment to the individual patient response, thereby reducing toxicity without compromising local control (LC).

MATERIALS AND METHODS

We analyzed HCC patients receiving 3-5 fraction SBRT at our institution from 2005 to 2017. Over this time, patients were offered enrollment on prospective trials assessing individualized adaptive SBRT. Based on normal tissue complication probability and modeling of changes in liver function following a 1-month treatment break between fractions 3 and 4, patients could receive a total of 3 or 5 fractions. Patients not on trial received 3 or 5 fractions without a break. Toxicity was defined as a ≥2 point rise in Child-Pugh (CP) score within 6 months of SBRT.

RESULTS

178 patients were treated with SBRT to 263 HCCs. Median follow-up was 23 months. 86 treatments had a 1-month break. 1-Year LC was 95.4%; this was not different between patients treated with or without a break (p = 0.14). Controlling for tumor size and dose a break was not associated with inferior LC (HR: 0.58, 95%CI: 0.1-3.34, p = 0.54). 54 patients experienced a ≥2 point rise in CP score. Controlling for the number of prior liver directed therapies and mean liver dose, a treatment break reduced the odds of toxicity (OR: 0.42, 95% CI: 0.17-1.03, p = 0.06).

CONCLUSION

A one-month mid-treatment break and reassessment may reduce the odds of treatment related toxicity without compromising LC.

First Measurement of Near-Threshold J/ψ Exclusive Photoproduction off the Proton

We report on the measurement of the γp→J/ψp cross section from E_{γ}=11.8  GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment. We find that the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section dσ/dt has an exponential slope of 1.67±0.39  GeV^{-2} at 10.7 GeV average energy. The LHCb pentaquark candidates P_{c}^{+} can be produced in the s channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions B(P_{c}^{+}→J/ψp) and cross sections σ(γp→P_{c}^{+})×B(P_{c}^{+}→J/ψp).

Plunging ranula with lingual nerve tether: Case report and literature review

Plunging ranulas are most often treated surgically; various surgical approaches may be necessary depending on the unique characteristics of each case. Here, we present the case of a plunging ranula noted on imaging to have a cordlike tether, which was revealed intraoperatively to be the lingual nerve. This case illustrates the importance of preoperative imaging for surgical planning, and when a transcervical approach may be the best choice for plunging ranulas.

Immunogenic and antigenic heterogeneity of Blastocystis sp. subtype 3 from symptomatic and asymptomatic individuals

Blastocystis sp. subtype 3 (ST3) has been implicated previously to be phenotypically heterogeneous between isolates from symptomatic and asymptomatic persons in previous studies. The aim of this study is to identify the immunogenic and antigenic heterogeneity among three different isolates of Blastocystis sp. ST3 isolated from asymptomatic and symptomatic individuals. Immunogenic and antigenic profile of ST3 isolates was assessed through splenocyte proliferation, cytokine assessment and antibody measurements. The total IgG antibody responses in mice immunised with symptomatic (0.736±0.033) and asymptomatic (0.426±0.025) of ST3 Blastocystis sp. were significantly higher compared to the controls respectively. High secretions of IgG antibody mixture of IgG1/IgG2a antibodies were detected in sera of mice immunised with symptomatic and asymptomatic solubilised Blastocystis sp. Antigen (Blastocystis-Ag). Predominant IgG1 production was detected higher in mice injected with Blastocystis sp. ST 3 from asymptomatic individuals (0.148±0.016) (P<0.05) whereas predominant IgG2a production was detected higher in mice injected with the same subtype but from the symptomatic individuals (0.355±0.021). This data was supported by the production of significantly higher Th1 (IFNγ and IL-2) response (393.56±49.21) and (628.89±31.06) respectively in symptomatic isolates compared to Th2 (IL-4 and IL-10) response (93±7.85) and (103.22±11.33) in asymptomatic isolates after in-vitro stimulations. Splenocyte stimulation index (SI) was detected higher in symptomatic Blastocystis-Ag group. This study is the first to demonstrate antigenic and immunogenic heterogeneity among ST3 symptomatic and asymptomatic Blastocystis-Ag with symptomatic isolates being highly immunogenic and antigenic. No significant variations among the three isolates of asymptomatic and symptomatic groups. The study supports the suggestion from previous study that surface variations between symptomatic and asymptomatic isolates as well their distinct phenotypic variation despite being the same subtype may have caused the differences in the distinct immune responses.

Synthesis and Spectral Studies of Iron(III), Ruthenium(III) and Rhodium(III) Complexes with New Tetraaza Macrocyclic Ligands

Complexes of iron(III), ruthenium(III) and rhodium(III) with three new tetraaza macrocyclic ligands, oxo4bzo3[14]triene-N4[TBTAC14Tone], oxo4bzo2[14]diene-N4[DBTAC14Tone] and oxo4bzo2[15]diene-N4[DBTAC15Tone] have been prepared and characterised. The complexes are found to have the formulae [FeLCl2]Cl. 2H2O, [RuLCl2]Cl. 3H2O and [RhLCl2]Cl. 2H2O. The cations adopt a trans-dichloro configuration with the six-coordinated trivalent metal ions in a pseudo-octahedral geometry.

Rational use of intravenous polymyxin B and colistin: A review

Polymyxin B and colistin (polymyxin E) were introduced in clinical practice to treat Gram-negative infections in 1950s but their parenteral use waned in 1970s due to toxicity concerns. Resurgence of polymyxins use in Malaysia began approximately in 2009 due to a lack of treatment options for MDR Gram negative superbugs such as Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa. However, limited experience and a lack of widespread availability of up-to-date dosing guidelines could potentially result in incorrect use of these last resort antibiotics by managing doctors. The recent report of polymyxin resistant strains is also a cause of concern. Herein, we discuss the importance of preserving the efficacy of polymyxins in hospitals, the similarities and differences between polymyxin B and colistin, issues pertaining to current use of polymxyins and strategies to improve polymyxins' prescription. Polymyxins should only be used to treat significant infections, in optimum doses and if possible, in combination with other antibiotics.

Bifurcation delay in a network of locally coupled slow-fast systems

We study the evolution of bifurcation delay in a network of locally coupled slow-fast systems. Our study reveals that a tiny perturbation even in a single node causes asymmetry in bifurcation delay. We investigate the evolution of bifurcation delay as a function of various parameters, such as feedback coupling strength, amplitude of external force, frequency of external force, and delay coupling strength. We show that a traveling wave is generated as the result of introducing local parameter mismatch, and the bifurcation delay shows a dip in the spatial profile. We believe that these spatiotemporal patterns in bifurcation delay shed light on the dynamics of neuronal networks.

A novel green approach for reduction of free standing graphene oxide: electrical and electronic structural investigations

Ion beam irradiation technique has been proposed, for efficient, fast and eco-friendly reduction of graphene oxide (GO), as an alternative to the conventional methods. 5 MeV, Au⁺ ion beam has been used to reduce the free standing GO flake. Both electronic and nuclear energy loss mechanisms of the irradiation process play a major role in removal of oxygen moieties and recovery of graphene network. Atomic resolution scanning tunnelling microscopy analysis of the irradiated GO flake shows the characteristic honeycomb structure of graphene. X-ray absorption near edge structure analysis at C K-edge reveals that the features of the irradiated GO flake resemble the few layer graphene. Resonant Rutherford backscattering spectrometry analysis evidenced an enhanced C/O ratio of ∼23 in the irradiated GO. In situ sheet resistance measurements exhibit a sharp decrease of resistance (few 100 s of Ω) at a fluence of 6.5 × 10¹⁴ ions cm^-2. Photoluminescence spectroscopic analysis of irradiated GO shows a sharp blue emission, while pristine GO exhibits a broad emission in the visible-near IR region. Region selective reduction, tunable electrical and optical properties by controlling C/O ratio makes ion irradiation as a versatile tool for the green reduction of GO for diverse applications.

Impact of pH on the viability and morphology of Blastocystis isolates

Blastocystis sp. is ubiquitous in avian, mammalian and human hosts and propagates in either neutral or slightly alkaline conditions within the host's gastro-intestinal tract. Of the few previous studies on this enteric protozoan parasite in feline and canine hosts, prevalence values have been shown to range between 0 to 70.8%. In view of the close association between humans, and canine and feline hosts as companion animals, faecal samples of 180 Felis catus and 82 Canis lupus, collected from Penang and Kuala Lumpur, Malaysia, were initially screened by in vitro cultivation followed by molecular characterization. No positive isolates were identified in culture but in 12 feline samples DNA barcoding detected a zoonotic subtype Blastocystis ST1 for the first time. Consequently, avian and human isolates, which had previously been successfully cultured, were used to investigate the impact of pH on the viability and morphology of Blastocystis sp. The use of Trypan blue showed that the number of viable cells increased when exposed to pH 4 and a significant increase in viability occurred in pH values of 5 to 7. Development of Blastocystis cells in both isolates was suppressed in media less than pH 5 followed by the disappearance of viable cells from avian isolates in more acidic media below pH 4. Morphologically at pH 4 cells from avian isolates were less rounded, and with wrinkled / shrunken surfaces, than the more normal rounded cells from human isolates. On the other hand, at values below pH 3, no viable cells in human isolates were visible. The present findings therefore confirm that gastro-intestinal pH is an important determinant of Blastocystis viability and consequently influences the epidemiology of infection within avian, mammalian and human hosts.

Genetic diversity of rodent Blastocystis sp. from Peninsular Malaysia

Rodents are ubiquitous zoonotic vectors for many human pathogens including Blastocystis sp. In this study, we examined the prevalence and subtypes of Blastocystis sp. in rodents captured from Peninsular Malaysia. A total of 293 rodents predominantly brown rat (Rattus norvegicus) (290 of 293, 99.0%) and house shrew (Suncus murinus) (3 of 293, 1.0 %), were captured in the vicinity of popular eateries in two cities (Kuala Lumpur and Ipoh) in Peninsular Malaysia. In vitro cultivation method showed presence of Blastocystis sp. in approximately half (133 of 290, 45.9%) of the brown rats tested. Among the 47 Blastocystis isolates subtyped using partial small subunit ribosomal RNA gene analysis, ST4 was the most abundant (43 of 47, 91.5%) followed by ST1 (2 of 47, 4.3%), ST5 (1 of 47, 2.1%) and ST7 (1 of 47, 2.1%). Our findings highlighted the importance of rodents as a source of Blastocystis sp. infection in Malaysia and showed the high prevalence of ST4 within the rodent population infected with Blastocystis sp.

The Association of External Transfer Status with Adverse Outcomes in Otolaryngology

Objective To compare rates of morbidity and mortality in patients treated by otolaryngologists who undergo interhospital transfers vs those who do not and to quantify conditions requiring interhospital transfers in this population. Study Design Cohort study. Setting American College of Surgeons National Surgical Quality Improvement Program. Subjects and Methods We identified patients requiring surgery by otolaryngologists in the National Surgical Quality Improvement Program database from 2006 to 2013. We compared patients who were transferred from an outside institution to those admitted from home. Multivariate regression was used to adjust for patient characteristics, comorbidities, and case mix. The primary outcome was overall morbidity and mortality within 30 days of surgery. Results We identified 60,498 patients; 488 (0.8%) were transferred from another institution. Operations that were more common in the transferred group were incision and drainage (24.0% vs 1.2%), facial trauma repair (9.0% vs 3.1%), and oropharyngeal hemorrhage control (3.9% vs 0.4%). External transfer patients had significantly longer hospital stays (44.1% vs 4.4% >7 days, P < .05). On unadjusted analysis, transferred patients had a significantly higher rate of morbidity and mortality (odds ratio [OR], 11.3; 95% confidence interval [CI], 9.4-13.5). On multivariate analysis, transferred patients had a significantly greater rate of morbidity and mortality (OR, 3.1; 95% CI, 2.4-4.0). Conclusion Transfer from another institution is associated with worse outcomes independent of case mix, demographics, and preoperative comorbidities in acute otolaryngology conditions requiring surgery. Practitioners should be aware of this when caring for transfer patients, and transfer status should be considered when measuring hospital quality.