Improvements in target coverage and reduced spinal cord irradiation using intensity-modulated radiotherapy (IMRT) in patients with carcinoma of the thyroid gland.

BACKGROUND AND PURPOSE: External beam radiotherapy for thyroid carcinoma poses a significant technical challenge as the target volume lies close to or surrounds the spinal cord. The potential of intensity-modulated radiotherapy (IMRT) to improve the dose distributions was investigated. MATERIALS AND METHODS: A planning study was performed on patients with thyroid carcinoma. Plans were generated to irradiate the thyroid bed alone or to treat the thyroid bed and the loco-regional lymph nodes in two phases. Conventional plans with minimal beam shaping were compared to three-dimensional conformal radiotherapy (3DCRT) and inverse-planned IMRT plans to assess target coverage and normal tissue sparing. IMRT techniques were optimized to find the minimum number of equispaced beams required to achieve the clinical benefit and a concomitant boost technique was explored. RESULTS: For the thyroid bed alone and the thyroid bed plus loco-regional lymph nodes, conventional and conformal techniques produced low minimum doses to the planning target volume (PTV) if spinal cord tolerance was respected. 3DCRT reduced the irradiated volume of normal tissue (P=0.01). IMRT plans achieved the goal dose to the PTV (P<0.01) and also reduced the spinal cord maximum dose (P<0.01). IMRT, using a concomitant boost technique, produced better target coverage than a two-phase technique. For both the two-phase and concomitant boost techniques, IMRT plans with seven and five equispaced fields produced similar dose distributions to nine fields, but three fields were significantly worse. CONCLUSIONS: 3DCRT reduced normal tissue irradiation compared to conventional techniques, but did not improve PTV or spinal cord doses. IMRT improved the PTV coverage and reduced the spinal cord dose. A simultaneous integrated boost technique with five equispaced fields produced the best dose distribution. IMRT should reduce the risk of myelopathy or may allow dose escalation in patients with thyroid cancer.     

Clavicle in Carnivorans: A Forgotten Bone

The clavicle is a bone whose development is related to the versatility of the thoracic limbs in mammals. Studies with vestigial structures are scarce and controversial, especially in the order Carnivora. The objective of this study was to verify the presence and to investigate the shape and constitution of the clavicle in neotropical carnivores. In order to do this, 108 cadavers of 19 different species were collected dead on highways and were analyzed. The clavicles were submitted to dissections, longitudinal length measurements, radiographs, histological sections and, in some cases, diaphanization. Sixteen of the 19 species had clavicles in both sides, being significantly larger (P < 0.05) and distinctly more radiopaque in the felids than in the other families. There were no macro or microscopic evidence of clavicle in the specimens of Nasua nasua (n = 6), Conepatus semistriatus (n = 2), and Conepatus chinga (n = 1). The clavicle of the males of Lycalopex gymnocercus, Galictis cuja, and Leopardus geoffroyi was significantly larger (P < 0.05). The predominating contour of the clavicles was a thin stick with cranial convexity. The histological sections demonstrated compact bone consisting of trabecula and lamellae filled by bone marrow and different levels of occupation by chondroid matrix. It can be proposed the clavicles of the order Carnivora, although vestigial and rarely absent, have their presence, constitution and shape more associated with the phylogenetic proximity and evolutionary history of the species than to the variety of movements the thoracic limbs perform in free-living conditions. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1831–1841, 2020. © 2019 American Association for Anatomy     

LOWER LIMB ASYMMETRIES IN RHYTHMIC GYMNASTICS ATHLETES

Background

Different limb training demands and limb preference may determine anthropometric and muscle force inter-limb asymmetries in Rhythmic Gymnastics (RG) athletes.

Purpose

The purpose of this study was to evaluate the influence of lateral preference of the lower extremity on anthropometric, range of motion, and isokinetic torque measurements of RG athletes.

Study Design

Cross sectional study

Methods

Lower limb anthropometric measurements (girth, estimated anatomical cross-sectional area), hip, knee and ankle range of motion, flexor and extensor isokinetic torques (angular velocities = 60, 180, e 240 °·s⁻¹) and bilateral asymmetry index were evaluated in 11 international level Rhythmic Gymnastics athletes (17.9 ± 4.0 years of age; 9.1 ± 5,1 years of experience; 26.8 ± 6.0 weekly training hours).

Results

The preferred limb showed larger thigh girth and anatomical cross-sectional area, higher ankle dorsiflexor range of motion, higher hip flexor torque at 60 °·s⁻¹ and higher plantarflexor torque at 180 °·s⁻¹ compared to the non-preferred limb.

Conclusions

The observed differences seem to be strictly related to lateral preference and rhythmic gymnastics training.

Levels of Evidence

3     

Intrabodies targeting the Kaposi sarcoma-associated herpesvirus latency antigen inhibit viral persistence in lymphoma cells

Kaposi sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen-1 (LANA1) is essential for the maintenance and segregation of viral episomes in KSHV latently infected B cells. We report development of intracellular, rabbit-derived antibodies generated by phage display technology, which bind to N-terminal LANA1 epitopes and neutralize the chromosome-binding activity of LANA1. Although these cloned single-chain variable fragments (scFvs) show relatively low binding affinities for the LANA1 viral antigen in in vitro assays, they nonetheless outcompete KSHV-seropositive human sera for LANA1 epitope binding. In heterologous cells, intracellular intrabody expression inhibits LANA1-dependent plasmid maintenance of both an artificial plasmid containing KSHV LANA1 binding sequences and a bacterial artificial chromosome containing the entire KSHV genome. In KSHV naturally infected primary effusion lymphoma cells, intracellular intrabody expression causes a reduction or loss of the typical LANA1 punctate, nuclear pattern. This morphologically apparent LANA1 dispersion correlates to loss of viral episome by molecular analysis. These data suggest a novel approach to antiherpes viral therapy and confirm LANA1 is critical target for neutralization of KSHV viral latency.     

Analytical optimization of the cutting efficiency for generic cavitation bubbles

A theoretical method to determine the optimum laser parameters for maximizing the cutting efficiency for different materials (in particular human cornea) is proposed. The model is simple and reduced to laser beam characteristics and cavitation properties. The model further provides a method to convert energy fluctuations during the cutting process to equivalent deviations in the cavitation bubbles. The proposed model can be used for calibration, verification and validation purposes of laser systems used for cutting processes at relatively low cost and may improve the quality of the results.     

Temporal relation between body mass index and renal function in individuals with hypertension and excess body weight

ObjectiveRecent evidence has suggested obesity as an independent risk factor for chronic kidney disease. However, the temporal relation between body mass index (BMI) and early renal dysfunction is unknown. This study aimed at evaluating whether longitudinal variations in BMI would reflect on changes in estimated glomerular filtration rate (GFR) in hypertensive individuals with excess body weight.MethodsThis was a cross-sectional, longitudinal study.ResultsOf the 218 participants who attended the first examination, 150 were available for paired final analyses. At the end of follow-up, GFR decreased by 1.024 mL/min for each 1-kg/m² increment in BMI (P < 0.03). When BMI was analyzed in quartiles, a positive graded relation with GFR changes was observed in quartiles 1 and 2 (individuals who maintained or lost weight), and a negative relation in quartiles 3 and 4 (individuals who gained weight, P = 0.05). A significant difference was observed between the smallest and highest BMI quartiles (P = 0.01). At the end of follow-up, the 76 participants (51%) who gained weight (+4.6 ± 0.4 kg) showed a reduction in GFR (?2.99 ± 1.99 mL/min) of borderline significance (P = 0.06) and a significant increase in fasting plasma glucose and triacylglycerol levels. Conversely, the 74 participants who maintained or lost weight showed no significant change in GFR and in fasting plasma glucose and triacylglycerol levels, although their blood pressure decreased significantly.ConclusionsOur study showed a significant temporal association between changes in BMI and GFR in overweight and obese hypertensive patients.     

Use of oral glutamine in radiation-induced adverse effects in patients with thoracic and upper aerodigestive malignancies: Results of a prospective observational study

Cancer growth in host tissues features glutamine (gln) depletion over time, decreasing epithelial cells'' optimal functioning. In addition, radiotherapy (RT) and/or chemotherapy (CT) cause damage to normal tissues, probably enhanced by this depletion. The present study prospectively examined the effect of gln supplementation on 72 patients with thoracic and upper aerodigestive malignancies (T&UAM) treated with sequential or concurrent RT-CT or RT alone. All patients received prophylactic gln powder 15 g bid for the full duration of treatment. The severity of acute radiation toxicities was graded according to the RT Oncology Group/European Organization for Research and Treatment of Cancer criteria. Primary endpoints were the incidence of grade >2 toxicities, weight loss and requirement for analgesics, and the secondary endpoint was the association of the length of irradiated esophagus from treatment planning with the use of opioids. The incidence of adverse effects was as follows: Grade >2 stomatitis, 25.0%; esophagitis, 60.5%; dysphagia, 54.2%; pain, 25.4%; mycosis, 40.8%. Stomatitis grade >2 was more frequent in patients with head and neck tumors (P<0.001) and in those with prior surgery (P<0.001). Esophagitis (P=0.020) and dysphagia (P=0.008) grade >2 were more frequent in patients with concurrent RT-CT. Regarding analgesics, 9.9% of patients received no pain treatment, 56.3% received simple analgesic therapy and 33.8% opioids. Patients on opioid therapy had a greater mean length of irradiated esophagus (P=0.024) or length >12 cm (P=0.018). In 54.2% of patients, weight loss was observed, particularly with concurrent RT-CT (P=0.007). Thus, the use of oral gln may have an important role in reducing acute radiation toxicities and weight loss, and in lowering the requirement for analgesics in patients with T&UAM. Further randomized trials are required to identify the appropriate gln dose, duration of treatment and precise radiation dosimetric parameters in this group of patients. The present clinical trial was retrospectively registered in the ClinicalTrials.gov Protocol Registration and Results System (registration no. {"type":"clinical-trial","attrs":{"text":"NCT05054517","term_id":"NCT05054517"}}NCT05054517/22-09-2021).     

Estimation of LDL cholesterol based on the Friedewald formula and on apo B levels

OBJECTIVES: The plasma apolipoprotein B (apo B) concentrations have been considered to be a more accurate representation of atherogenic particles and it has been proposed that the formula LDL-C (mmol/L) = 0.41TC - 0.32TG + 1.70apo B - 0.27 is reliable for the estimation of LDL-C (Clin Chem 1997; 43: 808-15). We undertook the present study to investigate the reliability of this formula in a large number of hyperlipidemic patients. DESIGN AND METHODS: 1) The Friedewald formula (LDL-F) and the apo B-based formula (LDL-B) were compared with the beta-quantification reference procedure in 130 individuals with a wide range of total cholesterol (TC) and triglyceride (TG) levels, and 2) the LDL-C levels obtained by the Friedewald formula were compared with those calculated by the apo B-based formula in 1010 individuals attending our outpatient lipid clinic. RESULTS: The LDL-F and the LDL-B formulae for LDL-C estimation were found to be in good agreement with the beta-quantification (r = 0.96 and 0.97, respectively). The bias of each method plotted as a function of TG (up to 4.52 mmol/L) was found positive for the LDL-F, whereas the LDL-B was independent of the concentrations of TG. When a large number of individuals were examined, a good correlation between the two equations was found (n = 1010, r = 0.98). The difference between the two methods was not correlated with serum TG levels. However, it was correlated to serum TC, and apo B levels. CONCLUSIONS: The LDL-B formula is a more reliable and accurate method than the LDL-F formula, especially at TG levels >2.26 mmol/L, although it underestimates LDL-C concentrations. Furthermore, this equation can be used in hypertriglyceridemic patients (TG >4.52 mmol/L) in whom the Friedewald equation is inaccurate.