Radiation reduction of minimally invasive transforaminal lumbar interbody fusion with localisation system in overweight patients: practical technique

AIMS

Minimally invasive transforaminal lumbar interbody fusion (MITLIF) has been well validated in overweight and obese patients who are consequently subject to a higher radiation exposure. This prospective multicentre study aimed to investigate the efficacy of a novel lumbar localisation system for MITLIF in overweight patients.

PATIENTS AND METHODS

The initial study group consisted of 175 patients. After excluding 49 patients for various reasons, 126 patients were divided into two groups. Those in Group A were treated using the localisation system while those in Group B were treated by conventional means. The primary outcomes were the effective radiation dosage to the surgeon and the exposure time.

RESULTS

There were 62 patients in Group A and 64 in Group B. The mean effective dosage was 0.0217 mSv (standard deviation (sd) 0.0079) in Group A and 0.0383 mSv (sd 0.0104) in Group B (p < 0.001). The mean fluoroscopy exposure time was 26.42 seconds (sd 5.91) in Group A and 40.67 seconds (sd 8.18) in Group B (p < 0.001). The operating time was 175.56 minutes (sd 32.23) and 206.08 minutes (sd 30.15) (p < 0.001), respectively. The mean pre-operative localisation time was 4.73 minutes (sd 0.84) in Group A and 7.03 minutes (sd 1.51) in Group B (p < 0.001). The mean screw placement time was 47.37 minutes (sd 10.43) in Group A and 67.86 minutes (sd 14.15) in Group B (p < 0.001). The pedicle screw violation rate was 0.35% (one out of 283) in Group A and 2.79% (eight out of 287) in Group B (p = 0.020).

CONCLUSION

The study shows that the localisation system can effectively reduce radiation exposure, exposure time, operating time, pre-operative localisation time, and screw placement time in overweight patients undergoing MITLIF. Cite this article: Bone Joint J 2017;99-B:944-50.

Next Generation Driver for Attosecond and Laser-plasma Physics

The observation and manipulation of electron dynamics in matter call for attosecond light pulses, routinely available from high-order harmonic generation driven by few-femtosecond lasers. However, the energy limitation of these lasers supports only weak sources and correspondingly linear attosecond studies. Here we report on an optical parametric synthesizer designed for nonlinear attosecond optics and relativistic laser-plasma physics. This synthesizer uniquely combines ultra-relativistic focused intensities of about 10²⁰ W/cm² with a pulse duration of sub-two carrier-wave cycles. The coherent combination of two sequentially amplified and complementary spectral ranges yields sub-5-fs pulses with multi-TW peak power. The application of this source allows the generation of a broad spectral continuum at 100-eV photon energy in gases as well as high-order harmonics in relativistic plasmas. Unprecedented spatio-temporal confinement of light now permits the investigation of electric-field-driven electron phenomena in the relativistic regime and ultimately the rise of next-generation intense isolated attosecond sources.

Porous monolith microfluidics for bacterial cell-to-cell communication assays

Genetically engineered bacteria can be used for a wide range of applications, from monitoring environmental toxins to studying complex communication networks in the human digestive system. Although great strides have been made in studying single strains of bacteria in well-controlled microfluidic environments, there remains a need for tools to reliably control and measure communication between multiple discrete bacterial populations. Stable long-term experiments (e.g., days) with controlled population sizes and regulated input (e.g., concentration) and output measurements can reveal fundamental limits of cell-to-cell communication. In this work, we developed a microfluidic platform that utilizes a porous monolith to reliably and stably partition adjacent strains of bacteria while allowing molecular communication between them for several days. We measured small molecule production by the bacterial populations in response to stimuli using analytical chemistry methods and measured fluorescent output. The results are compared with communication and diffusion delay models. This porous monolith microfluidic system enables bacterial cell-to-cell communication assays with dynamic control of inputs, relatively long-term experimentation with no cross contamination, and stable bacterial population size. This system can serve as a valuable tool in understanding bacterial communication and improving biosensor design capabilities.

[Study on the serum 25-hydroxyvitamin D levels of benign paroxysmal positional vertigo patients]

Objective:To study whether serum 25-hydroxy vitamin D can be used as an independent indicator of prognosis in patients with benign paroxysmal positional vertigo. Method:Two hundred and two patients with BPPV were collected and divided into vitamin D deficiency group and control group according to their serum 25-OHD level. The severity of the symptoms and the recurrence rate were compared between the two groups. Result:Compared with the control group, patients with vitamin D deficiency group showed severer symptoms, either in longer duration of vertigo, lower success rate of repositioning maneuver treatment at the first time, or higher recurrence rate within six months. Conclusion:Serum 25-OHD level was negatively correlated with the severity and prognosis of BPPV, and could be used as an important index to evaluate the prognosis of BPPV.

[Comparison of ablation of left-sided accessory pathway by atrial septal and retrograde arterial approach]

Objective: To compare the advantages and disadvantages of radiofrequency ablation of left-sided accessory pathways by via atrial septal approach with retrograde through aortic approach. Methods: A total of 184 patients of left-side accessory pathways were treated in Taizhou People's Hospital and the Subei People's Hospital from March 2012 to August 2015.A total of 103 cases were treated by aortic retrograde approach as through arterial group, 81 cases were treated by punctured atrial septal to left atrial for mapping and ablation as through atrial septal group.Comparison of ablation procedure time, total and pathways of different parts(subgroup) at instant success and relapse rates, safety (serious complications), and statistics other complications in operation and postoperative. Results: Through arterial group and through atrial septal group were no significant difference (P>0.05) in the ablation procedure time((25±18 ) vs (22±15)min ), instant success(98.1% vs 97.5%) and relapse rates(1.0% vs 1.2%), security(1 vs 0 case). There was no statistical difference in septal part subgroups (all P>0.05) in the ablation procedure time((22±18)vs (25±19)min), instant success(91.7% vs 89.9 %) and relapse rates(0 vs 11.1%); posterior wall subgroup had no statistical difference in the ablation procedure time((18±15)vs (16±12)min), instant success(100% vs 100 %) and relapse rates(0 vs 0)(all P>0.05); side wall subgroup had no statistical difference in the ablation procedure time((29±20)vs (21±18) min), instant success (98.3% vs 98.1%)and relapse rates(1.7% vs 0%)(all P>0.05). Conclusion: Ablation of left-sided accessory pathways by transseptal approach and transaortic approach has no statistical difference in the procedure time, instant success and relapse rates, security.In a particular case, there is a certain complementarity between the two methods.

Abstract P1-08-08: Identification of tumor-promoting and tumor-inhibiting genes with age dependent expression in breast cancer patients

Age is the number one risk factor for breast cancer development. The breast cancer incidence rate increases with age, following beta distribution, which is approximately linear in range from 30 to 70 years old [1]. Transcriptome alterations have been shown to promote tumorigenesis for many types of cancers. Therefore, we hypothesize that the genes with altered expression during aging may promote breast cancer development and/or progression. Using The Cancer Genome Atlas data, we extracted whole transcriptome profiling data of matched normal tissues from 82 female patients with age at diagnosis and menopausal status available. First, we applied simple linear regression to study the association between gene expression level and age at diagnosis on all the 82 patients. 258 upregulated and 240 downregulated genes are identified, which are associated with age. Secondly, 493 upregulated and 254 downregulated genes are identified that are altered by menopause by comparing post-menopausal to pre-menopausal patients (FDR &lt; 0.05). Exclusion of these menopause affected genes from those genes affected by age (258 upregulated and 240 downregulated) results in 148 upregulated and 189 downregulated genes during aging. Thirdly, by comparing matched tumor and adjacent normal samples, 3356 upregulated and 3124 downregulated genes are found to be associated with tumorigenesis. Overlapping of tumorigenesis associated genes with age dependent genes result in 14 upregulated and 24 downregulated genes that are both age and tumorigenesis associated. This discovery is being validated with normal breast tissues from donors in GTEx cohort. Experimental manipulation of the upregulated genes in seven breast cancer cell lines, representing five subtypes of breast cancer, demonstrated their essential role in promoting tumor malignancy, suggesting the upregulation is not merely passenger event. In a large mixed cohort, this panel of genes have significant predictive value in relapse free survival of breast cancer patients.

Funding: CPRIT Research Training Award (RP140105); NIH R01CA192564

Reference:

Francesco Pompei and Richard Wilson (2001). Age Distribution of Cancer: The incidence Turnover at Old Age. Human and Ecological Risk Assessment: Vol. 7, No. 6, pp. 1619-1650.

Citation Format: Gu X, Zhu H, Sun L. Identification of tumor-promoting and tumor-inhibiting genes with age dependent expression in breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-08-08.

Low levels of plasma galanin in obese subjects with hypertension

BACKGROUND

Obesity is strongly linked to increased blood pressure, which increases the risk of cardiovascular diseases. To our knowledge, little literature reported the information about galanin levels in obese individuals with hypertension. Therefore, the aim of this study was to investigate the possible involvement of galanin in the pathogenesis of obese subjects with hypertension.

METHODS

We measured body mass index and blood pressure of 38 obese patients with hypertension, 44 obese controls with normal blood pressure and 44 lean controls with normal blood pressure. Blood samples from all cases were collected at 8:00 a.m. after an overnight fast to determine the fasting plasma concentration of galanin, glucose, insulin, triglyceride, total cholesterol, high- and low-density lipoprotein cholesterol.

RESULTS

We found that plasma galanin levels were significantly decreased in obese patients with hypertension compared with the obese control group, whereas the galanin levels were significantly increased in obese controls compared with lean controls. Furthermore, in both obese groups the galanin levels were negatively correlative to diastolic blood pressure and positively correlative to insulin and triglyceride levels, but not to heart rate.

CONCLUSIONS

Low galanin levels were one of characters of obese patients with high blood pressure, and this levels may be taken as a novel biomarker to predict the development of high blood pressure in obese patients.

[The characteristic of lexical tone perception in native Mandarin speakers with mild and moderate sensorineural hearing loss]

Objective:To explore the characteristic of lexical tone perception in native-Mandarin speakers with mild to moderate sensorineural hearing loss. Method:Three types of continuum(Tone1/tone2, tone1/tone4 and tone2/tone3) were constructed and each of them includes a 15 stimuli. All speech stimuli in these three continua were resynthesized by applying the Pitch-Synchronous OverLap and Add(PSOLA) method implemented in Praat to the same mandarin syllable, /a/, with a high level tone produced by a female native-mandarin speaker. Twenty-three native-mandarin sensory hearing loss people were recruited for this study and identification task was used to acquire the tonal perceptual data. SPSS 19.0 software was used to get the fitting curves of lexical tone perception. Result:①Each tone perception curves owns the characteristic of categorical perception, including an obvious boundary, a definite intersection and the abrupt performance change at intersection. The tone perception curves were S-shape in SNHL people which were same as that in normal hearing people.②No significant performance difference of each continuum was observed between SNHL and NH in this study(P=0.811 in T1/T2 continuum, P=0.528 in T1/T4 continuum, P=0.555 in T2/T3 continuum). Conclusion:There is the categorical perception of lexical tone identification in native-mandarin sensorineural hearing loss people. The slight damage in peripheral auditory system did not changed characteristic of lexical tone perception.

Glucagon-like peptide 1 improves insulin resistance in vitro through anti-inflammation of macrophages

Glucagon-like peptide 1 (GLP-1), a kind of gut hormone, is used in the treatment of type 2 diabetes (T2D). Emerging evidence indicates that GLP-1 has anti-inflammatory activity. Chronic inflammation in the adipose tissue of obese individuals is a cause of insulin resistance and T2D. We hypothesized that GLP-1 analogue therapy in patients with T2D could suppress the inflammatory response of macrophages, and therefore inhibit insulin resistance. Our results showed that GLP-1 agonist (exendin-4) not only attenuated macrophage infiltration, but also inhibited the macrophage secretion of inflammatory cytokines including TNF-β, IL-6, and IL-1β. Furthermore, we observed that lipopolysaccharide (LPS)-induced macrophage conditioned media could impair insulin-stimulated glucose uptake. This effect was compensated by treatment with the conditioned media from macrophages treated with the combination of LPS and exendin-4. It was also observed that exendin-4 directly inhibited the activation of NF-κB in macrophages. In conclusion, our results indicated that GLP-1 improved inflammatory macrophage-derived insulin resistance by inhibiting NF-κB pathway and secretion of inflammatory cytokines in macrophages. Furthermore, our observations suggested that the anti-inflammatory effect of GLP-1 on macrophages can contribute to GLP-1 analogue therapy of T2D.

[The characteristic of lexical tone perception in native-mandarin normal hearing people]

Objective:The aim of this study is to explore the characteristic of lexical tone perception in nativemandarin normal hearing speakers.Method:Three types of continuum(Tone1/Tone2, Tone1/Tone4 and Tone2/Tone3) were constructed and each of them includes a 15 stimuli. All speech stimuli in these three continua were resynthesized by applying the PitchSynchronous OverLap and Add(PSOLA) method implemented in Praat to the same mandarin syllable, /a/, with a high level tone produced by a female native mandarin speaker. Forty native listeners of mandarin were recruited for this study and identification task was used to acquire the tonal perceptual data. SPSS 19.0 software was used to get the fitting curves of lexical tone perception. Result: The tone perception curves in nativemandarin normal hearing speakers were inverted Sshape. All the three tone perception curves showed steep upward or downward trend and obvious boundary.Each of tone perception curves has a definite intersection, and the tone perception performance has mutated at the intersection.Conclusion:There is the typically categorical perception of lexical tone identification in nativemandarin normal hearing people.

Blockade of Interleukin-17 Restrains the Development of Acute Lung Injury

The acute respiratory distress syndrome (ARDS), a clinical complication of severe acute lung injury (ALI) in humans, is a leading cause of morbidity and mortality in critically ill patients. Here, we explored the association between IL-17 and development of ALI using LPS-induced murine model. We found that IL-17 level was elevated in bronchoalveolar lavage (BAL) fluid of ALI mice. Upregulation of IL-17 resulted in increased severity of ALI as evidenced by decreased body weight and survival rate, elevated level of total protein and albumin in BAL fluid, as well as more apparent histopathology changes of lung. Induction of ALI was impaired in IL-17-deficient mice. Management of IL-17 could modulate LPS-induced pulmonary inflammation, as reflected by the total cell and neutrophil counts, proinflammatory cytokines, as well as chemokines in BAL fluid. Of note, blockade of IL-17 effectively inhibited the lung inflammation and alleviated ALI severity. Finally, we confirmed the clinical relevance and found that IL-17 expression was elevated and associated with the disease severity in patients with ARDS. In essence, IL-17 was crucial for development of ALI, suggesting a potential application for IL-17-based therapy in clinical practice.

Inverse 4D conformal planning for lung SBRT using particle swarm optimization

A critical aspect of highly potent regimens such as lung stereotactic body radiation therapy (SBRT) is to avoid collateral toxicity while achieving planning target volume (PTV) coverage. In this work, we describe four dimensional conformal radiotherapy using a highly parallelizable swarm intelligence-based stochastic optimization technique. Conventional lung CRT-SBRT uses a 4DCT to create an internal target volume and then, using forward-planning, generates a 3D conformal plan. In contrast, we investigate an inverse-planning strategy that uses 4DCT data to create a 4D conformal plan, which is optimized across the three spatial dimensions (3D) as well as time, as represented by the respiratory phase. The key idea is to use respiratory motion as an additional degree of freedom. We iteratively adjust fluence weights for all beam apertures across all respiratory phases considering OAR sparing, PTV coverage and delivery efficiency. To demonstrate proof-of-concept, five non-small-cell lung cancer SBRT patients were retrospectively studied. The 4D optimized plans achieved PTV coverage comparable to the corresponding clinically delivered plans while showing significantly superior OAR sparing ranging from 26% to 83% for D max heart, 10%-41% for D max esophagus, 31%-68% for D max spinal cord and 7%-32% for V 13 lung.