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Background Volatile organic compounds (VOCs) in exhaled breath are closely associated with respiratory diseases and are linked to various metabolic reactions in the human body. A quantitative analytical method can provide technical support for studying VOCs related to various diseases. Objective To establish a thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method for the determination of 27 VOCs in exhaled breath. Methods VOCs in exhaled breath were collected using a Bio-VOC sampler and enriched with Tenax TA thermal desorption tubes before TD-GC-MS analysis. Standards were collected using thermal desorption tubes and optimized for thermal desorption conditions as well as chromatographic and mass spectrometric conditions: The separation of the 27 VOCs was achieved by an optimized temperature program, the improvement of sensitivity by optimizing quantitative ions, and the increase of VOCs desorption efficiency by optimizing thermal desorption time and temperature. Limit of detection, limit of quantification, accuracy, precision, and stability of the proposed method were investigated by spiking with a blank gas bag, and exhaled breath samples from 20 healthy individuals were collected for an application study of the proposed method. Results The thermal desorption temperature was 280 ℃, and desorption time was 6 min. A VF-624ms chromatographic column was selected for the separation of target substances. The initial temperature of heating program was 35 ℃, maintained for 1 min, and then increased to 100 ℃ at a heating rate of 3 ℃·min−1 for 1 min, followed by increasing to 210 ℃ at a heating rate of 28 ℃·min−1 for 5 min. A quantitative analysis was conducted with a single ion monitoring (SIM) mode. Under these conditions, the 27 VOCs showed good linear relationships in their respective concentration ranges and the correlation coefficients were higher than 0.9990. The limits of detection of the method were in the range of 0.01-0.13 nmol·mol−1, the limits of quantification were in the range of 0.02-0.44 nmol·mol−1, and the spiked recoveries were in the range of 80.1%-120.5%, with intra-batch and inter-batch precision ≤ 18.8% and 17.9% respectively. All substances can be stored at room temperature (23-28 °C) for 7 d and at 4 °C for 14 d. The proposed method was applied to exhaled breath samples from 20 subjects with detection rates≥ 80% (except for trans-2-pentene and decane) and a concentration range of 0.00-465.50 nmol·mol−1. Conclusion The established TD-GC-MS method for quantification of VOCs in exhaled breath is characterized by high sensitivity and good accuracy, and is suitable for quantitative determination of VOCs in exhaled breath, which can provide technical support for the study of exhaled breath VOCs.
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The diverse clinical manifestations of Langerhans cell histiocytosis (LCH) present a dilemma to clinicians and pediatricians play an important role in its diagnosis and multidisciplinary approach. LCH, previously known as histiocytosis X, is an uncommon hematological disorder characterized by uncontrolled stimulation and proliferation of normal antigen-presenting cells, Langerhans cells. The purpose of this report is to describe the case of a 7-month-old female child with multisystem involvement who presented with breath-holding spells and to discuss the clinical, radiological, and histopathological features of LCH.
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Background: Currently, recommended heart dose constraints are difficult to meet in whole?breast irradiation (WBI) for left?sided breast cancer patients, who cannot be treated with the deep inspiration breath hold. We performed a radiotherapy planning study to establish if the use of intensity?modulated radiation therapy (IMRT) or volumetric?modulated arc therapy (VMAT) allows for better sparing of the heart and its subvolumes than the three?dimensional conformal radiation therapy (3D?CRT), and how these attempts affect the dose delivered to the other organs. Methods: A total of 17 left?sided and 10 right?sided consecutive patients treated with free?breathing WBI were retrospectively included. The 3D?CRT, IMRT, and VMAT plans were generated. Several dose杤olume parameters and plan quality indices were compared, separately for the left? and right?sided plans. Results: All the techniques fulfilled the planning objectives. In the left?sided plans, there was no heart or left ventricle dose reduction with IMRT, nor with VMAT; the maximum dose in the left anterior descending coronary artery was reduced with VMAT (P = 0.005); V5 for the contralateral breast, contralateral lung, and total?body increased markedly in VMAT, and for the ipsilateral lung (V5IL) also in IMRT, compared with 3D?CRT (P < 0.001). In the right?sided plans, the V5 values, except for V5IL, did not differ between the three techniques. Conclusions: IMRT and VMAT had a limited heart?sparing benefit in the left?sided free?breathing WBI, at the cost of increased low?dose volumes, measured by V5. The low?dose volumes are not increased by IMRT or VMAT in the right?sided WBI, where heart sparing is not a problem, but the attempts to reduce cardiac doses in the left?sided WBI increase them.
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Cardiotoxicity caused by postoperative radiotherapy can increase the risk of cardiovascular adverse events in patients with breast cancer, especially those with left breast cancer, which is proportional to the dose of radiation to the heart. It has been proved that deep inspiration breath-hold (DIBH) technique can significantly reduce the cardiac dose in patients with left breast cancer, but the benefits of this technique vary greatly among different patients, and its implementation requires additional equipment, time, manpower and other resources. Hence, it is necessary to select patients who are suitable for this technique in advance. In addition to comprehensive analysis of general factors before simulation positioning that affect DIBH selection, this review also systematically summarized relevant indicators of CT simulation positioning images. These anatomical indicators included the measurement of the cardiac contact distances in parasagittal (CCD ps) plane, the lateral heart-to-chest distance (HCD), the product of maximum heart width (HW max) and the maximum heart depth (HD max) during CT simulation positioning, and the maximum heart distance, heart volume in the irradiation field (HVIF), the difference of lung volume and heart volume between free breathing (FB) and DIBH measured after CT localization. All of them showed some instructive significance for evaluating whether DIBH should be applied in tangent field based radiotherapy planning. The automatic planning (rapid plan) function in the treatment planning system could quickly predict the benefit of DIBH for breast cancer patients. The purpose of this article is to help clinicians select patients who are suitable for DIBH technique, guaranteeing that DIBH technique resources can be used reasonably.
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Objective:To investigate the effect of helicobacter pylori (HP) infection and eradication treatment on small intestinal bacterial overgrowth (SIBO) in children.Methods:A prospective case-control study was conducted to select 68 children with symptoms of abdominal distension, abdominal pain, diarrhea and suspected digestive system diseases admitted to the Affiliated Hospital of Xuzhou Medical University from June 2021 to June 2022. They were divided into HP negative group and HP positive group according to HP infection. HP positive group received triple standardized HP eradication treatment, 14 days as a course of treatment. The baseline SIBO positive rate and gastrointestinal symptom rating scale (GSRS) score of the two groups were compared. The HP positive group was followed up for 4 and 12 weeks after drug withdrawal for quantitative assessment of gastrointestinal symptoms and LHBT. The SIBO positive rate, GSRS score of the two groups and the change of SIBO positive rate and GSRS score of the HP positive group before and after treatment were compared. The measurement data with normal distribution were expressed, and independent sample t-test was used for comparison between the two groups. M( Q1, Q3) was used to represent the measurement data of non normal distribution, and Mann Whitney U test was used to compare the two groups; Friedman test was used for comparison between multiple time points, and Nemenyi test was used for pairwise comparison. Four grid table or paired χ 2 test was used to compare the counting data between groups. Results:The positive rate of SIBO in HP negative group was lower than that in HP positive group (36.1% (13/36) vs 62.5% (20/32)), the difference was statistically significant (χ 2=4.72, P=0.030). Four weeks after drug withdrawal, the SIBO positive rate in HP positive group was higher than that before treatment (87.5% (28/32) vs 62.5% (20/32)), and 12 weeks after drug withdrawal was lower than that before treatment (21.9% (7/32) vs 62.5% (20/32)), with statistically significant differences (χ 2=8.00, P=0.008; χ 2=13.00, P<0.001). There was no statistically significant difference in GSRS score between HP negative group and HP positive group ( P=0.098). The clinical symptoms of 32 children in HP positive group were improved 4 and 12 weeks after HP eradication was stopped. GSRS scores were lower than those before treatment (8.0 (6.0, 12.8), 7.0 (5.0, 9.0) points vs 15.0 (12.0, 19.0) points) , and the differences were statistically significant ( Z values were -3.91, -4.68, respectively; all P<0.001). Conclusions:HP infection can increase the positive rate of SIBO in children with suspected digestive system diseases. The standardized triple HP eradication therapy may further aggravate the overgrowth of intestinal bacteria while treating HP infection, but this effect can be eliminated after 12 weeks of treatment.
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Objective:To investigate the changes and clinical significance of multiple cytokine levels in exhaled breath condensate (EBC) in patients undergoing tracheotomy with severe inhalation injury.Methods:A prospective study was conducted. A total of 32 patients with severe burn combined with severe inhalation injury admitted to the department of burns and plastic surgery of Affiliated Suzhou Hospital of Nanjing Medical University from May 2021 to August 2022 were enrolled. Twenty healthy volunteers from the same period were served as controls. EBC of patients at 12 hours after burn and the samples of healthy controls were collected. The levels of 27 cytokines in EBC, including tumor necrosis factor-α (TNF-α) and interleukins (IL-1β, IL-6, IL-8, IL-10, and IL-17), were determined by liquid phase chip technology. Meanwhile, plasma of patients at 12 hours after burn and the plasma of volunteers were collected, and the levels of inflammatory cytokines were detected by liquid chip technology, and the differences between the levels in plasma and those in EBC were analyzed. Plasma and EBC of patients with aspiration injury were collected at 12 hours and 3, 7, 14 and 21 days after burn, and TNF-α levels were determined by enzyme-linked immunosorbent assay (ELISA).Results:Finally, 32 patients were enrolled, and the total burned area was (40±16)% of total body surface area (TBSA). The time of admission was (4.2±2.3) hours after injury. ① Twenty-seven cytokines in EBC: 18 kinds of cytokines including macrophage inflammatory protein-1β (MIP-1β), IL-6, IL-5, IL-2, IL-1β, IL-8, IL-10, IL-15, IL-9, interferon-γ (IFN-γ), IL-1 receptor antagonist (IL-1ra), TNF-α, chemotactic factor for eosinophil (Eotaxin), basic fibroblast growth factor (bFGF), platelet derived growth factor-BB (PDGF-BB), interferon-inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), granulocyte colony-stimulating factor (G-CSF) were significantly increased in patients with severe aspiration injury compared with health controls. Eotaxin was not detected in EBC of healthy controls. Five cytokines, granulocyte-macrophage colony-stimulating factor (GM-CSF), chemokine ligand 5 (CCL5/RANTES), IL-13, IL-4 and MIP-1α, were not detected in EBC of severe inhalation injury patients and healthy controls. Vascular endothelial growth factor (VEGF) and IL-12 p70 in EBC of severe aspiration injury patients were slightly decreased as compared with healthy controls, while IL-7 and IL-17 were slightly increased, but the differences were not statistically significant. ② Six inflammatory cytokines in plasma: the levels of IL-6 and IL-8 in the severe aspiration injury group were significantly increased as compared with healthy controls [IL-6 (ng/L): 18.51 (10.87, 26.21) vs. 0.22 (0.10, 0.36), IL-8 (ng/L): 10.75 (8.58, 18.79) vs. 1.06 (0.81, 2.14), both P < 0.01]. The plasma levels of TNF-α, IL-1β and IL-10 were slightly increased in patients with severe aspiration injury as compared with healthy controls, and IL-17 was slightly decreased, but the difference was not statistically significant. In the EBC collected during the same period, five inflammatory cytokines, including TNF-α, IL-1β, IL-6, IL-8 and IL-10, in patients with severe inhalation injury were significantly increased as compared with healthy controls [TNF-α (ng/L): 16.42 (12.57, 19.21) vs. 7.34 (6.11, 8.69), IL-1β (ng/L): 15.57 (10.53, 20.25) vs. 0.99 (0.67, 1.41), IL-6 (ng/L): 13.36 (9.76, 16.54) vs. 0.70 (0.42, 0.85), IL-8 (ng/L): 1 059.29 (906.91, 1 462.37) vs. 10.36 (8.40, 12.37), IL-10 (ng/L): 2.69 (1.54, 3.33) vs. 1.54 (1.18, 2.06), all P < 0.05]. ③ Dynamic changes of TNF-α in plasma and EBC: the level of TNF-α in EBC of patients with severe aspiration injury was lower than that in plasma. Plasma TNF-α level was increased gradually with the extension of time after injury, and was significantly higher than that of healthy controls on day 3 [ng/L: 30.38 (24.32, 39.19) vs. 22.94 (17.15, 30.74), P < 0.05], and reached the peak on day 14, then fell back. The level of TNF-α in EBC at 12 hours after injury was significantly higher than that in healthy controls [ng/L: 15.34 (11.75, 18.14) vs. 6.99 (6.53, 7.84), P < 0.01], and reached the peak on 3 days after injury, and then gradually decreased. Conclusion:There are changes in the expression of multiple cytokines in EBC of patients with severe inhalation injury, and the changes of many inflammatory cytokines including TNF-α are more sensitive than those in plasma, which can be used to monitor and evaluate the condition of patients with inhalation injury.
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Exhaled ammonia(NH3)is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualitative and quantitative analysis of exhaled NH3 with high selectivity and sensitivity.Acetone was introduced into the drift tube along with the drift gas as a modifier,and the characteristic NH3 product ion peak of(C3H6O)4NH4+(K0=1.45 cm2/V·s)was obtained through the ion-molecule reaction with acetone reactant ions(C3H6O)2H+(K0=1.87 cm2/V·s),which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH3 qualitative identification.Moreover,the interference of high humidity and the memory effect of NH3 molecules were significantly reduced via online dilution and purging sampling,thus realizing breath-by-breath measurement.As a result,a wide quantitative range of 5.87-140.92 μmol/L with a response time of 40 ms was achieved,and the exhaled NH3 profile could be synchronized with the concentration curve of exhaled CO2.Finally,the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH3 of healthy subjects,demon-strating its great potential for clinical disease diagnosis.
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@#Abstract: Objective To explore the correlation between lung function in patients with chronic obstructive pulmonary disease (COPD) and tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) levels in exhaled breath condensate (EBC), and to provide a convenient methodological basis for the diagnosis and treatment of COPD and the determination of its efficacy. Methods A total of 81 COPD patients and 40 healthy controls were selected from the respiratory department of the Fourth Affiliated Hospital of Guangzhou Medical University from August 2020 to February 2022 as the research subjects. The COPD patients were divided into 41 cases in the acute exacerbation group and 40 cases in the remission group according to their status. All participants underwent lung function detection, venous blood and EBC collection, and the levels of TNF-α and IL-1β in EBC and venous blood were analyzed by enzyme-linked immunosorbent assay (ELISA), and correlation analysis was performed by Pearson correlation analysis method. Results The levels of TNF-α and IL-1β in EBC of in the acute exacerbation group, the healthy control group, the remission group were (5.16±0.18) pg/μL and (7.75±0.27) pg/μL, (2.66±0.31) pg/μL and (2.41±0.24） pg/μL, (3.61±0.29) pg/μL and (3.17±0.38) pg/μL, respectively. Compared with the healthy control group, the levels of TNF-α and IL-1β in EBC in the COPD acute exacerbation group were significantly higher than those in the healthy control group and the COPD remission group (F=9.451, 8.217, P<0.001). Serum tests were consistent with this result. Correlation analysis showed that the levels of TNF-α and IL-1β in EBC were significantly positively correlated with the level of serum inflammation levels (P<0.001), while significantly negatively correlated with lung function (P<0.001). Conclusions TNF-α and IL-1β in EBC are potential biomarkers of inflammation in patients with COPD, and their detection can be used to effectively assess lung function in patients with COPD.
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Abstract Objective: To compare the Rapid Shallow Breathing Index (RSBI) obtained by the ventilometer and from mechanical ventilation parameters. Methods: Randomized crossover trial, including 33 intubated patients, on mechanical ventilation for at least 24 hours, undergoing spontaneous breathing test. Patients were submitted to the measurement of RSBI by four methods: disconnected from the ventilator through the ventilometer; in Pressure Support Ventilation (PSV) mode at a pressure of 7 cm H2O; in Continuous Positive Airway Pressure (CPAP) mode at a pressure of 5 cmH2O with flow trigger; in CPAP mode at a pressure of 5 cmH2O with pressure trigger. Results: No significant difference was detected between the RSBI obtained by the ventilometer and in the CPAP mode with flow and pressure triggers, however, in the PSV mode, the values were lower than in the other measurements (p < 0.001). By selecting patients from the sample with higher RSBI (≥ 80 cycles.min−1.L−1), the value of the index obtained by the ventilometer was higher than that obtained in the three options of ventilation methods. Conclusion: The RSBI obtained in the CPAP mode at a pressure of 5 cmH2O, in both triggers types, did not differ from that measured by the ventilometer; it is, therefore, an alternative when obtaining it from mechanical ventilation parameters is necessary. However, in the presence of borderline values, the RSBI measured by ventilometer is recommended, as in this method the values are significantly higher than in the three ventilation modalities investigated.
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Respiration, Artificial , Ventilator Weaning , Breath Tests , Airway Extubation , Intensive Care UnitsABSTRACT
Objective:To evaluate liver functional reserve in healthy subjects of different age groups using the L-[1- 13C]-phenylalanine breath test( 13C-pheBT)and to investigate the patterns of changes in liver functional reserve with aging in comparison with elderly cirrhosis patients. Methods:Thirty-seven healthy volunteers were divided into a young and middle-aged group(n=10), an early elderly group(n=9), an advanced elderly group(n=9)and a longevity group(n=9). Eight elderly patients with liver cirrhosis were selected as the control group.An oral dose of 100 mg 13C-phe was administered to each subject.Expired breath samples were collected at pre-dose and at 12 different time points within 150 minutes post-dose.Isotope ratio mass spectrometer was used to measure the abundance of 13C.The percentage of the 13C excretion rate( 13CO 2ERt), the percentage of 13C cumulative excretion( 13Ccumt)at different time points, and the percentage of the 13C peak excretion rate( 13CO 2ERmax)after drug administration were calculated.In addition, associations between 13C-pheBT and common liver function parameters were analyzed. Results:Compared with healthy volunteers, 13CO 2ER 30, 13CO 2ER 45, 13CO 2ER 60, 13Ccum 45, 13Ccum 60, 13Ccum 75, 13Ccum 90 and 13Ccum 105, 13Ccum 120, 13Ccum 135, 13Ccum 150 showed significant differences in the longevity group, the young and middle-aged group and the young elderly group.There were statistically significant differences between the elderly cirrhosis group and the healthy volunteers in each subgroup(all P<0.05); The mean values of 13CO 2ERmax, 13CO 2ER 30, 13Ccum 45, 13Ccum 60, 13Ccum 75, 13Ccum 90, 13Ccum 105, 13Ccum 120, 13Ccum 135, 13Ccum 150 decreased following the order of the young and middle-aged group, the early elderly group, the advanced elderly group, the longevity group, and the elderly cirrhosis group(all P<0.05). In healthy volunteers, the 13CO 2 exclusion rate curve and the cumulative exclusion rate curve showed that the curves of the young and middle-aged group and the early elderly group almost overlapped, while the curves of the advanced group and the longevity group decreased with age, and the difference between the longevity group and the young and middle-aged group and between the longevity group and the early elderly group was markedly prominent. Conclusions:13C-pheBT is a safe, sensitive and reliable test for quantitation of liver function.Our recommendations include collecting samples within an hour of drug administration and using 13CO 2ERmax, 13CO 2ER 30, 13Ccum 45 and 13Ccum 60 as the main parameters.Overall, the functional reserve and compensatory capability of the liver are robust.The decline in liver functional reserve in healthy individuals is a gradual and slow process, with a significant decrease after age 80 and more so after age 90.
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BACKGROUND: The urea breath test (UBT-13C) is a non-invasive technique that allows the diagnosis and confirmation of eradication of Helicobacter pylori infection. Aim: To evaluate H. pylori positivity and values of UBT-13C among infected Chilean children and adults, and to analyze its variation in relation to sex, nutritional status, and age of the patients. Material and Methods: Retrospective study of 1141 patients aged 6 to 94 years, with an indication for a UBT-13C either for diagnosis or for confirmation of eradication of H. pylori infection. 13C enrichment was measured using an infrared spectrometer calculating the delta 13C values before and after the ingestion of 13C marked urea. The clinical data of the patients were obtained at the time of the examination. Results: We included 241 children and 900 adults. Infected children obtained lower UBT-13C delta values than infected adults (16.1 ± 8.7 and 37 ± 52.9, respectively). The rates of infection were higher in males who were recruited for diagnosis. Significant differences were obtained between positivity for H. pylori in overweight and obese children but not adults. UBT-13C titers were significantly associated with the body mass index (BMI) only in adults. Conclusions: H. pylori infection rates are similar between sexes and are higher in children probably because of selection bias. In children, H. pylori positivity is associated with higher BMI and excess malnutrition although with similar UBT-13C values. In adults, H. pylori infection is not related with BMI, but a higher BMI impacts UBT-13C titers.
ANTECEDENTES: La prueba de aliento con urea (UBT-13C) es una técnica no invasiva que permite el diagnóstico y confirmación de erradicación de la infección por Helicobacter pylori. Objetivo: Evaluar los valores de UBT- 13C en niños y adultos chilenos infectados y analizar su variación en relación al sexo, diagnóstico nutricional y edad de los pacientes. Material y Métodos: Estudio retrospectivo de 1.141 pacientes de 6 a 94 años. El enriquecimiento de13C se midió usando un espectrómetro de infrarrojos, calculando el delta 13C antes y después de la ingesta de urea marcada con 13C. Los datos clínicos de los pacientes se obtuvieron al momento del examen. Resultados: Incluimos 241 niños y 900 adultos con valores delta de UBT-13C de 16,1 ± 8,7 frente a 37 ± 52,9, respectivamente. Las tasas de infección fueron mayores en los hombres reclutados para el diagnóstico. Se obtuvieron diferencias significativas entre la positividad para H. pylori en niños con sobrepeso y obesidad, pero no en adultos. Los títulos de UBT-13C se asociaron significativamente con el índice de masa corporal (IMC) solo en adultos. Conclusiones: Las tasas de infección por H. pylori son similares entre los sexos y aumentan en los niños probablemente debido al sesgo de selección. En niños, la positividad para H. pylori se asocia con un IMC más alto y malnutrición por exceso, aunque con valores similares de UBT-13C. En los adultos, la infección por H. pylori no se relaciona con el IMC ni con la obesidad, pero el aumento del IMC afecta los títulos de UBT-13C.
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Humans , Female , Helicobacter pylori , Helicobacter Infections/diagnosis , Pediatric Obesity , Urea , Breath Tests , Carbon Isotopes , Body Mass Index , Child , Retrospective Studies , Sensitivity and SpecificityABSTRACT
ABSTRACT BACKGROUND: The prevalence of Helico bacter pylori (H. pylori) infection is decreasing worldwide, but is still high in developing countries. We previously observed an H. pylori infection rate of 52% among children and adolescents with chronic non-ulcer dyspepsia. OBJECTIVE: To investigate the prevalence of H. pylori infection among asymptomatic children living in a single region and to evaluate the risk factors for this infection. DESIGN AND SETTING: Cross-sectional study in which 161 children aged 5-13 years (mean age 7.8 years), at a public school in Botucatu, state of São Paulo, southeastern Brazil, were assessed. METHOD: The children's H. pylori infection status was determined through the urea breath test and the risk factors for acquisition of the infection were determined based on a sociodemographic questionnaire. RESULTS: The overall prevalence of H. pylori infection was 20.5%: 18.7% among females and 22.2% among males. The results from the sociodemographic survey did not differ between children with and without H. pylori infection. 30.9% of the children had previous records of upper gastrointestinal symptoms, which consisted of H. pylori infection in only 26.5% of these cases. Family histories of gastritis and peptic ulcer disease were found in relation to 50% and 32.3% of the children with H. pylori infection respectively. CONCLUSION: The prevalence of H. pylori infection among asymptomatic children in southeastern Brazil is lower than that recorded among symptomatic children in the same region and similar to the prevalence of H. pylori infection observed in developed countries.
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The unique characteristics of 2-dimensional hetero structure offers efficient gas sensing with high selectivity to identify gases from the interference gases which is quite difficult. In the present work, ZnO: SnO2Nano composite clusters (NCC) is prepared. A resistive metal oxide volatile organic compound (VOC) gas sensor is fabricated with nullifying the effect of humidity by increasing temperature optimally. A single-step SOL-GEL (SG) synthesis is used to prepare ZnO: SnO2 NCC with maximum Zn/Sn molar concentration ratio of 3. The morphological studies through Scanning Electron Microscopy (SEM), electrical properties due to oxygen vacancies and energy band variations of Nanocomposite are measured. The enhancement of gas sensor sensitivity due to highly mesoporous nature of the composite is observed. From the findings, the abundant mesopores in the range of 2 nm-14 nm and specific surface area of 54.2 m2 g?1 with the average crystal size of 14.236 nm, and polar surface area of the composite 25.9651Åis achieved. When compared to bare ZnO and SnO2 gas sensors, the present gas sensor offers the higher selectivity with enhanced performance due to the mesoporous structure. Fast repeatability rate of 2200 sec at 350?C to ethanol is attained and the overall selectivity of the sensor increased twice as 2.085. The NCC compound is tested firstly with micro organisms such as B. subtilis (B. S), Bacillus cereus (B. C), B. coagulans (B. C), Pseudonymous auriginosa (P. A) are considered for antimicrobial activity. From the findings, zinc stannate compound showed good efficacy towards B. cereus Gram positive and P.A gram-negative. A bacterial growth is arrested highly with B. cereus.
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A comprehensive analysis of volatile organic compounds (VOCs) from the exhaled breath sample is termed as breathomics. Breath samples are a complex mixture composed of a multitude of VOCs and other molecules. The analysis of total VOCs in exhaled breath provides a promising tool for the diagnosis of many diseases because it enables the observation of biochemical processes in the body in a non?invasive way. VOCs are produced in various physiological and pathophysiological conditions thus making it a potential biomarker for several diseases.
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RESUMEN Objetivo: Evaluar un test del aliento con carbono 13 de fabricación China como método diagnóstico no invasivo para la infección por Hp en población peruana a través de la determinación de sensibilidad, especificidad, valor predictivo positivo y negativo, likelihood ratio positivo y negativo y utilidad diagnóstica. Materiales y métodos: Se realizó un estudio transversal y descriptivo sobre una base de datos secundaria del Servicio de Gastroenterología del Hospital Cayetano Heredia y Clínica Cayetano Heredia de noviembre de 2017 a agosto de 2018. Se incluyó a pacientes mayores de 18 años sometidos a una endoscopía digestiva alta. Resultados: Se halló una sensibilidad de 90,3% (IC 95% 0,81-0,96), especificidad de 82,5% (IC 95% 0,67-0,93), valor predictivo positivo y negativo de 90,3% y 82,5%, y likelihood ratio positivo y negativo de 5,16 y 0,12, respectivamente. El área bajo la curva ROC fue 0,88 (IC 95%: 0,80-0,96). Conclusiones: El test del aliento con carbono 13 es una prueba no invasiva y sencilla que proporciona resultados de forma rápida. Sin embargo, no es posible recomendar el uso rutinario de esta prueba debido a la discrepancia entre los resultados internacionales y locales obtenidos. Se sugiere realizar estudios con mayores tamaños muestrales, protocolos estandarizados y de diferentes fabricantes para evaluar su rendimiento y características.
ABSTRACT Objective: To evaluate a Chinese-made carbon-13 breath test as a non-invasive diagnostic method for Hp infection in the Peruvian population through the determination of sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio, and diagnostic utility. Materials and methods: A cross-sectional and descriptive study was carried out on a secondary database of the Gastroenterology Service of the Cayetano Heredia Hospital and Cayetano Heredia Clinic from November 2017 to August 2018. Patients over 18 years of age who underwent endoscopy were included upper digestive. Results: A sensitivity of 90.3% (95% CI 0.81-0.96), a specificity of 82.5% (95% CI 0.67-0.93), a positive predictive value was found and negative of 90.3% and 82.5%, and positive and negative likelihood ratio of 5.16 and 0.12, respectively. The area under the ROC curve was 0.88 (95% CI: 0.80-0.96). Conclusions: The carbon 13 breath test is a non-invasive and simple test that provides results quickly. However, it is not possible to recommend the routine use of this test due to the discrepancy between the international and local results obtained. Studies with larger sample sizes, standardized protocols and different manufacturers are suggested to evaluate their performance and characteristics.
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Surface guided radiation therapy (SGRT) is a method of radiation therapy with non-invasive and non-radiation image guidance technology, which uses continuous real-time imaging to monitor the whole course of treatment. This paper summarizes the characteristics, representative products, application in clinical research and treatment, and quality control of SGRT. This emerging technology plays an increasingly important role in delivering more precise, safe, and comfortable radiotherapy to patients.
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Objective:To monitor the cerebral vascular blood flow parameters in the early stage of simulated acute exposure to high altitude hypoxia by transcranial color Doppler (TCCD), and to evaluate the change trend of cerebral hemodynamics and cerebrovascular reactivity.Methods:Sixty-four healthy volunteers were selected to observe the changes of peak systolic flow velocity(Vs), end diastolic flow velocity(Vd), mean flow velocity(Vm), resistance index (RI) and pulsatility index (PI) of middle cerebral artery (MCA) 30 minutes after they quickly entered the simulated altitude of 4 500 meters. Combined with breath holding test, breath holding index (BHI) was used to evaluate cerebrovascular reactivity (CVR), and subjects were divided into ≤30 years old group and >30 years old group, and the changes of CVR after hypoxia of the two groups were compared.Results:In the early stage of hypoxic environment, compared with baseline, SpO 2 decreased, heart rate increased, and blood flow velocity of middle cerebral artery(Vs, Vd, Vm) increased significantly, BHI showed a decreasing trend (all P<0.01). After hypoxia, the BHI rate of change in >30 years old was lower than that of the subjects ≤30 years old ( P<0.05). After breath holding, cerebral blood flow velocity increased significantly, PI and RI decreased significantly (all P<0.01). Conclusions:Cerebral blood flow is very sensitive to hypoxia. The application of TCCD technology can evaluate the trend of cerebral blood flow dynamics and cerebrovascular reserve capacity in real time and accurately, which is helpful to provide objective basis and research basis for the prevention and treatment of high altitude hypoxia.
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Objective:To study the characteristics of breath sound spectroscopy in chronic obstructive pulmonary disease(COPD) patients with different lung function grades, to preliminarily determine the characteristic parameters and indicators of breath sound spectrograms with different lung function grades of COPD, and to explore the visualization and measurability of the differences in respiratory auscultation in patients with different lung function grades.Methods:Patients diagnosed and treated in Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Chongming Branch from October 2018 to December 2020 were selected. Fifty-two patients with COPD (22 patients with moderate to moderate obstructive ventilation dysfunction (mild to moderate group), 30 patients with severe obstructive ventilation dysfunction (severe group)) and 36 normal controls (control group) were selected. The respiratory sounds were sampled with an electronic stethoscope and transmitted to the audit audio software to calculate the relevant data of respiratory sound pressure level (SPL) and the ratio to minute ventilation (VE) of samples with different lung function grades. A retrospective case-control study was used. The data with normal distribution were analyzed by one-way ANOVA, and the pairwise comparison was performed by SNK- q test. Results:The breathing audio frequency of mild-moderate, severe COPD patients and the control group has a sound pressure difference of (-0.5±2.2) dB and (-1.6±6.1) dB, (0.7±4.0) dB, and there was significant difference between each group ( F=2.64, P=0.038). The sound pressure level per minute ventilation (SPL 50-200/VE) of respiratory sound inspiratory phase in COPD patients with mild to moderate and severe obstructive ventilation dysfunction and the control group were (5.7±1.8) dB/L, (6.1±2.3) dB/L and (5.4±0.9) dB/L, respectively. The expiratory SPL 50-200/VE were (5.8±1.7), (6.3±2.2) and (5.3±1.2) respectively. There was significant difference among the three groups ( Finhalation=3.26, P=0.048; Frespiration=2.44, P=0.045). ROC curve results showed that SPL 50-200/VE in the inspiratory phase, SPL 50-200/VE in the expiratory phase, and sound pressure difference to assess different grades of obstructive ventilatory dysfunction had diagnostic value (AUC values were 0.697, 0.725 and 0.686, respectively; and P values were 0.015, 0.005 and 0.022, respectively). In some patients with COPD, abnormally high energy levels may appear in the time-frequency diagram of breath sounds. Conclusion:There are significant differences in respiratory audio spectrum analysis between patients with different degrees of obstructive ventilation dysfunction and those with normal ventilation function, which can provide a basis for auxiliary judgment of obstructive ventilation dysfunction.
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The 13C-urea breath test is the most widely applied non-invasive test to diagnose Helicobacter pylori (Hp) infection in children.The fasting time, dose and formulation of labeled urea, type of test meal, time of breath collection, device to detect breath samples, cut-off value of exhaled 13CO 2/ 12CO 2 breath delta value and the interpretation of results have been modified to improve the accuracy.The 13C-urea breath test possesses a good perfor-mance in diagnosing Hp infection and evaluating the eradication of infection after treatment in children.However, the high false-positive results in young children are caused by oral flora, endogenous CO 2 and fixed dose of labeled urea.In addition, taking proton pump inhibitors, antibiotics and bismuth before test, low bacterial density and peptic ulcer bleeding will lead to false negative results.This study aims to review the influencing factors of 13C-urea breath test in the diagnosis of Hp infection in children.
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Objective:To investigate the antibiotics resistance of patients with Helicobacter pylori ( H. pylori) infection of different age in Ningxia. Methods:From July to December 2021, a total of 1 040 patients with H. pylori infection confirmed by 14C-urea breath test who had no history of H. pylori treatment and underwent gastroscopy were selected from the H. pylori special outpatient clinics from Ningxia Hui Autonomous Region People′s Hospital, Ningxia Hospital of Integrated Traditional Chinese and Western Medicine, Yuanzhou District People′s Hospital of Guyuan, Wuzhong People′s Hospital, the Second People′s Hospital of Shizuishan, People′s Hospital of Zhongwei, Yinchuan First People′s Hospital. Gastric mucosa specimens were obtained under gastroscopy and cultured for H. pylori in vitro. Harvested H. pylori were detected for H. pylori drug resistance phenotype. Kirby-Bauer disk diffusion method was used to detect antibiotic sensitivity. Previous use of antibiotics of patients were recorded. The characteristics of primary drug resistance of people≤44, 45 to 59, and ≥60 years old were analyzed. Chi-square test was used for statistical analysis. Results:A total of 538 H. pylori strains were obtained from 1 040 gastric mucosa specimens cultured in vitro, with a positive rate of 51.7%. A total of 187 patients could provide information on history of antibiotics usage. The primary drug resistance rates of metronidazole, clarithromycin and levofloxacin were high, which were 95.5% (514/538), 44.6% (240/538) and 45.4% (244/538), respectively; however drug resistance of amoxicillin, furazolidone and tetracycline were not found. The double drug resistance rate was 36.4% (196/538), mainly resistant to metronidazole and clarithromycin or metronidazole and levofloxacin, the drug resistance rates were 17.8% (96/538), 18.2% (98/538), respecitively. The triple drug resistance rate was 25.5% (137/538), all of the strains were metronidazole, clarithromycin and levofloxacin resistant strains. The primary drug resistance rates to levofloxacin and clarithromycin in patients with H. pylori infection who had previous history of quinolones and macrolides were 60.9% (28/46) and 63.4% (83/131), respectively; which were higher than those of patients who had not used corresponding drugs (41.8%, 59/141 and 39.3%, 22/56), and the differences were statistically significant ( χ2=5.05 and 9.23, P=0.023, 0.002). The drug resistance rates of metronidazole of ≤44, 45 to 59, and ≥60 years old group were 94.2% (163/173), 95.5% (231/242) and 97.6% (120/123), respectively, and the differences were not significant ( P>0.05). The single drug resistance rates of levofloxacin of ≤44, 45 to 59, and ≥60 years old group were 34.7% (60/173), 48.3% (117/242) and 54.5% (67/123), respectively, and the differences were statistically significant ( χ2=12.95, P=0.002). The levofloxacin resistance rate of ≤44 years old group was lower than that of 45 to 59, and ≥60 years old group, and the differences were statistically significant ( χ2=7.70 and 11.49, P=0.006, 0.001). The single drug resistance rates of clarithromycin of ≤44, 45 to 59, and ≥60 years old group were 36.4% (63/173), 50.4% (122/242) and 44.7% (55/123), respectively, and the differences were statistically significant ( χ2=8.00, P=0.018). The clarithromycin resistance rate of ≤44 years old group was lower than 45 to 59 years old group, and the difference was statistically significant ( χ2=8.00, P=0.005). Dual drug resistance rates of levofloxacin and clarithromycin of ≤44, 45 to 59 and ≥60 years old group were 49.7%(86/173), 70.2%(170/242), 45.5%(56/123), and the difference was statistically significant( χ2=27.63, P<0.001). The resistance rate of clarithromycin and levofloxacin in 45 to 59 years old group was higher than that in ≤44 and ≥60 years old group, and the difference was statistically significant ( χ2=18.00 and 21.13, both P<0.001). Conclusions:Primary drug resistance rates to metronidazole, levofloxacin and clarithromycin are high in patients with H. pylori infection of different ages in Ningxia. Individualized eradication therapy guided by drug resistance test is recommended.