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71.
Sahil Sood Lavanya Gurram Dheera Aravindakshan John Paul Supriya Chopra Jamema Swamidas Akshay Patil Umesh Mahantshetty 《Brachytherapy》2021,20(3):550-556
PurposeThe study is an audit of reporting dose and volume specifications as per the ICRU 58 for MUPIT-based interstitial brachytherapy in gynecological cancers. Correlation between total reference air kerma (TRAK) and isodose surface was also evaluated to understand the intensity of treatment in interstitial brachytherapy.Methods and MaterialsForty-two patients underwent HDR MUPIT-based interstitial brachytherapy 20 Gy in five fractions after EBRT during 2017–2019. Treated volume, high and low-dose regions, mean central dose, Dose Homogeneity Index (DHI), organ at risk doses, and TRAK values were computed.ResultsHigh-dose regions V150 mean was 12.4 cc and V200 was 4.58 cc; and low-dose region was 75.92 cc. The mean treated volume was 59.8 cc. The mean central dose was 3.7 Gy. DHI was 79%. The mean D2cm3 bladder and rectum were 2.9 Gy and 2.8 Gy. The mean TRAK was 0.16 cGy per fraction per hour at 1 m. TRAK values showed significant correlation with various isodose volumes (TRAK and V100: r = 0.943 p < 0.0005; and TRAK and V50: r = 0.953; p < 0.0005). A positive correlation was observed between TRAK and the number of needles (r = 0.746; p < 0.0005). At a median followup of 16 months, 4 of 42 patients (9.5%) had local recurrences.ConclusionsOur study shows compliance with ICRU 58 recommendations along with certain deviations. Local recurrence rate is acceptable. TRAK shows correlation with surface isodose in MUPIT-based brachytherapy and should to be evaluated in future studies. 相似文献
72.
Amrita Mandal Hiu-Tung C. Wong Katherine Pinter Natalie Mosqueda Alisha Beirl Richa Madan Lomash Sehoon Won Katie S. Kindt Catherine M. Drerup 《The Journal of neuroscience》2021,41(7):1371
In neurons, mitochondria are transported by molecular motors throughout the cell to form and maintain functional neural connections. These organelles have many critical functions in neurons and are of high interest as their dysfunction is associated with disease. While the mechanics and impact of anterograde mitochondrial movement toward axon terminals are beginning to be understood, the frequency and function of retrograde (cell body directed) mitochondrial transport in neurons are still largely unexplored. While existing evidence indicates that some mitochondria are retrogradely transported for degradation in the cell body, the precise impact of disrupting retrograde transport on the organelles and the axon was unknown. Using long-term, in vivo imaging, we examined mitochondrial motility in zebrafish sensory and motor axons. We show that retrograde transport of mitochondria from axon terminals allows replacement of the axon terminal population within a day. By tracking these organelles, we show that not all mitochondria that leave the axon terminal are degraded; rather, they persist over several days. Disrupting retrograde mitochondrial flux in neurons leads to accumulation of aged organelles in axon terminals and loss of cell body mitochondria. Assays of neural circuit activity demonstrated that disrupting mitochondrial transport and function has no effect on sensory axon terminal activity but does negatively impact motor neuron axons. Taken together, our work supports a previously unappreciated role for retrograde mitochondrial transport in the maintenance of a homeostatic distribution of mitochondria in neurons and illustrates the downstream effects of disrupting this process on sensory and motor circuits.SIGNIFICANCE STATEMENT Disrupted mitochondrial transport has been linked to neurodegenerative disease. Retrograde transport of this organelle has been implicated in turnover of aged organelles through lysosomal degradation in the cell body. Consistent with this, we provide evidence that retrograde mitochondrial transport is important for removing aged organelles from axons; however, we show that these organelles are not solely degraded, rather they persist in neurons for days. Disrupting retrograde mitochondrial transport impacts the homeostatic distribution of mitochondria throughout the neuron and the function of motor, but not sensory, axon synapses. Together, our work shows the conserved reliance on retrograde mitochondrial transport for maintaining a healthy mitochondrial pool in neurons and illustrates the disparate effects of disrupting this process on sensory versus motor circuits. 相似文献
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Predicting pathological outcomes in patients undergoing robot‐assisted radical prostatectomy for high‐risk prostate cancer: a preoperative nomogram
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76.
Background
Neonatal birth weight is a powerful predictor of infant growth and survival and maternal factors like poor knowledge and insufficient dietary intake are significant risk factors. Other preventable determinants like pre pregnant BMI <18.5, low gestational weight gain (GWG) and anemia are also associated with low birth weight. This study was carried out to identify the impact of these maternal factors with risk of low birth weight (LBW).Methods
A longitudinal study was carried out on 124 booked antenatal cases at a tertiary care center. A validated protocol containing socio demography, food frequency and anthropometry was administered at the 3rd trimester. Birth weight of the newborn was noted after delivery.Results
26.28% children had low birth weight (<2500 g), 14.6% mothers were thin (BMI < 18.5), 55.3% mothers had a weight gain of less than 9 kgs and 45.5% were anemic. 81.81% mothers with BMI >18.5 and 28.92% women who were educated till high school had a baby with LBW. Most mothers consumed milk and vegetables daily and a few consumed non vegetarian foods but quality and quantity of food were grossly inadequate. GWG levels and Hb levels were significantly different in different birth weight groups and also were significantly associated with low birth weight.Conclusion
Quality and quantity of maternal dietary intake during pregnancy, even in normal weight mothers (BMI > 18.5), are important determinants of birth weight. Nutritional counseling for mothers during the antenatal period is the cornerstone for healthy mother and healthy child. 相似文献77.
V.K. Malhotra Navreet Singh R.S. Bishnoi D.S. Chadha P. Bhardwaj H. Madan R. Dutta A.K. Ghosh S. Sengupta P. Perumal 《Medical Journal Armed Forces India》2015,71(4):324-329
Background
Competitive sports training causes structural and conductive system changes manifesting by various electrocardiographic alterations. We undertook this study to assess the prevalence of abnormal ECG in trained Indian athletes and correlate it with the nature of sports training, that is endurance or strength training.Methods
We evaluated a standard resting, lying 12 lead Electrocardiogram (ECG) in 66 actively training Indian athletes. Standard diagnostic criteria were used to define various morphological ECG abnormalities.Results
33/66 (50%) of the athletes were undertaking endurance training while the other 33 (50%) were involved in a strength-training regimen. Overall 54/66 (81%) sportsmen had significant ECG changes. 68% of these changes were considered as normal training related features, while the remaining 32% were considered abnormal. There were seven common training related ECG changes–Sinus Bradycardia (21%), Sinus Arrhythmia (16%), 1st degree Atrioventricular Heart Block (6%), Type 1 2nd-degree Atrioventicular Heart Block (3%), Incomplete Right bundle branch block (RBBB) (24%), Early Repolarization (42%), Left Ventricular Hypertrophy (LVH) (14%); while three abnormal ECG changes--T-wave inversion (13%), RBBB(4%), Right ventricular hypertrophy (RVH) with strain (29%) were noted. Early repolarization (commonest change), sinus bradycardia, and incomplete RBBB were the commoner features noticed, with a significantly higher presence in the endurance trained athletes.Conclusion
A high proportion of athletes undergoing competitive level sports training are likely to have abnormal ECG recordings. Majority of these are benign, and related to the physiological adaptation to the extreme levels of exertion. These changes are commoner during endurance training (running) than strength training (weightlifting). 相似文献78.
Li Shen Pardeep S. Jhund Inder S. Anand Ankeet S. Bhatt Akshay S. Desai Aldo P. Maggioni Felipe A. Martinez Marc A. Pfeffer Adel R. Rizkala Jean L. Rouleau Karl Swedberg Muthiah Vaduganathan Orly Vardeny Dirk J. van Veldhuisen Faiez Zannad Michael R. Zile Milton Packer Scott D. Solomon John J.V. McMurray 《Journal of the American College of Cardiology》2021,77(16):1961-1973
BackgroundThe incidence of pneumonia and subsequent outcomes has not been compared in patients with heart failure and reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF).ObjectivesThis study aimed to examine the rate and impact of pneumonia in the PARADIGM-HF (Prospective Comparison of Angiotensin Receptor-Neprilysin Inhibitor With Angiotensin Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure) and PARAGON-HF (Prospective Comparison of ARNI with ARB Global Outcomes in Heart Failure with Preserved Ejection Fraction) trials.MethodsThe authors analyzed the incidence of investigator-reported pneumonia and the rates of HF hospitalization, cardiovascular death, and all-cause death before and after the occurrence of pneumonia, and estimated risk after the first occurrence of pneumonia in unadjusted and adjusted analyses (the latter including N-terminal pro–B-type natriuretic peptide).ResultsIn PARADIGM-HF, 528 patients (6.3%) developed pneumonia after randomization, giving an incidence rate of 29 (95% CI: 27 to 32) per 1,000 patient-years. In PARAGON-HF, 510 patients (10.6%) developed pneumonia, giving an incidence rate of 39 (95% CI: 36 to 42) per 1,000 patient-years. The subsequent risk of all trial outcomes was elevated after the occurrence of pneumonia. In PARADIGM-HF, the adjusted hazard ratio (HR) for the risk of death from any cause was 4.34 (95% CI: 3.73 to 5.05). The corresponding adjusted HR in PARAGON-HF was 3.76 (95% CI: 3.09 to 4.58).ConclusionsThe incidence of pneumonia was high in patients with HF, especially HFpEF, at around 3 times the expected rate. A first episode of pneumonia was associated with 4-fold higher mortality. (Prospective Comparison of Angiotensin Receptor–Neprilysin Inhibitor With Angiotensin-Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure [PARADIGM-HF], NCT01035255; Prospective Comparison of ARNI [Angiotensin Receptor–Neprilysin Inhibitor] With ARB [Angiotensin Receptor Blocker] Global Outcomes in Heart Failure With Preserved Ejection Fraction [PARAGON-HF], NCT01920711) 相似文献
79.
Ajay Madan rew Parkinson Morris D. Faiman 《Alcoholism, clinical and experimental research》1998,22(6):1212-1219
Diethyldithiocarbamate methyl ester (DDTC-Me) is a precursor to the formation of S-methyl-N,N-diethyliolcarbamate sulfoxide, the active metabolite proposed to be responsible for the alcohol deterrent effects of disulfiram. The present study investigated the role of human cytochrome P-450 (CYP) enzymes in sulfoxidation and thiono-oxidation of DDTC-Me, intermediary steps in the activation of disulfiram. Several approaches were used in an attempt to delineate the particular P-450 enzyme(s) involved in the sulfoxidation and thiono-oxidation of DDTC-Me. These approaches included the use of cDNA-expressed human P-450 enzymes, correlation analysis with sample-to-sample variation in human P-450 enzymes in a bank of human liver microsomes, and chemical and antibody inhibition studies. Multiple human P-450 enzymes (CYP3A4, CYPlA2, CYP2A6, and CYP2D6) catalyzed the sulfoxidation of DDTC-Me, as determined with cDNA-expressed enzymes. Several lines of evidence suggest that the sulfoxidation of DDTC-Me by human liver microsomes is primarily catalyzed by CYP3A4/5, including (1) a high correlation between DDTC-Me sulfoxidation and testosterone 6β-hydroxylation; (2) increased DDTC-Me sulfoxidation in the presence of α-naphthoflavone, an activator of CYP3A enzymes; (3) inhibition of this reaction by inhibitors of CYP3A4/5 enzymes, such as troleandomycin and ketoconazole; and (4) inhibition of DDTC-Mesulfoxidation by antibodies against CYP3A enzymes. On the other hand, several lines of evidence suggested that the thiono-oxidation of DDTC-Me by human liver microsomes is catalyzed in part by CYPlA2, CYP266, CYPPEl, and CYP3A4/5, including (1) these human P450 enzymes among others have the capacity to catalyze this reaction, as determined with cDNA-expressed enzymes; (2) a high correlation between DDTC-Me thiono-oxidation and testosterone 6β-hydroxylation, weak inhibition by ketoconazole, troleandomycin, and anti-CYP3A antibodies suggested a minor role for CYP3A4; (3) a high correlation with immunoreactive CYP2B6 suggested involvement of this enzyme; (4) weak inhibition of DDTC-Me thiono-oxidation by furafylline and anti-CYPlA antibody suggested involvement of CYPlA2, and (5) inhibition of DDTC-Me thiono-oxidation by DDTC and anti-CYP2E antibodies suggested a role for CYP2E1. Collectively, these data suggested CYP3A4/5 enzymes are the major contributors to the sulfoxidation of DDTC-Me by human liver microsomes, and CYPlA2, CYP2B6, CYP2E1, and CYP3A4/5 contribute toward DDTC-Me thiono-oxidation by human liver microsomes. This study, in conjunction with others (Madan et al., Drug Metab. Dispos. 23:1153–1162, 1995), may help explain the variability in disulfiram's effectiveness as an alcohol deterrent. 相似文献
80.