Purpose: Because the natural history of carotid body tumors is believed to be unpredictable, immediate surgical removal has been recommended. The present study reviews our experience in the diagnosis ...and treatment of these uncommon lesions.
Methods: The medical records of patients who appeared for treatment with carotid body tumors between 1981 and 1997 were reviewed. Patients demographics, mode of presentation, imaging and treatment modalities, Shamblin classification, and neurologic complications (stroke, cranial nerve injuries) were analyzed.
Results: Over the past 16 years, 31 patients with 32 carotid body tumors have been evaluated, with an average follow-up of 3.2 years. The patients were arbitrarily classified into two groups on the basis of the mode of detection. Seventy percent (23 of 32) of the tumors discovered on clinical or self-examination were classified as Group 1; 28% (9 of 32) of the tumors detected during duplex scanning for carotid artery disease (8) or MRI (1) were classified as Group 2. The mean size of chemodectomas found on palpation (4.3 ± 1.7 cm) was larger than that of those detected by duplex ultrasound (2.7 ± 1.0 cm;
p < 0.05, by paired
t test). Preoperative embolization was successfully performed in 5 of 6 instances of large tumors; the remaining patient suffered a procedure-related stroke. Thirty-one carotid body tumors were resected. In one case, the tumor was felt by the primary surgeon to be too small (0.9 × 0.7 cm on duplex scan) to warrant immediate excision; this patient is being followed by periodic duplex scanning. Five neurologic complications were noted in Group 1, one after preoperative embolization and four after surgery. One cranial nerve injury occurred in Group 2. One patient had a large recurrent chemodectoma with clinical evidence of metastatic disease.
Conclusion: The increasing use of sophisticated imaging modalities may allow earlier discovery of carotid body tumors before they can be clinically detected. Resection of carotid body tumors of all sizes in appropriate surgical candidates remains the standard of care. Unfortunately, resection of even small tumors is associated with a low but constant incidence of neurologic complications. (J Vasc Surg 1998;28:84-93)
The objective of this study was to evaluate nuclear normality in intracytoplasmic sperm injection (ICSI)‐selected epididymal sperm from obstructive azoospermic (OA) patients. We evaluated whether the ...selection criteria used in routine ICSI (morphology and motility at a magnification of 400×) is adequate for selecting “normal” sperm from epididymal samples. Surgically retrieved spermatozoa from the caput epididymis of 15 OA patients and ejaculated sperm samples from 9 normospermic donors were evaluated with a DNA‐specific stain (Feulgen) and in combination with the computerized karyometric image analysis (CKIA) system. Original (unselected) samples and ICSI‐selected sperm were compared in donor and patient samples. In the original fraction, a larger variation in almost all measured parameters was found in epididymal sperm than in ejaculated sperm. After sperm selection, the morphometry was comparable between epididymal and ejaculated sperm. However, for those parameters related to the DNA stainability and chromatin texture (nuclear condensation), significant differences between patients and donors were observed. This result suggests that the size and form of the sperm do not necessarily hold similar internal structures. Thus, the frequency of “normal” sperm significantly increased after ICSI selection, but the improvement was more marked in donor than in OA patients' samples. In conclusion, at least a twofold increase in the number of normal spermatozoa was achieved after ICSI selection. The heterogeneity in the stainability and chromatin condensation of epididymal samples from OA patients indicates that some of the selected spermatozoa have a hypocondensed or hypercondensed chromatin. Even in the best of donor cases, no more than 55% of the selected sperm scored normal with CKIA, indicating that the present routine ICSI selection criteria are not sufficient for selecting normal condensed nuclei.
EcoPatches Mariakakis, Alex; Chen, Sifang; Nguyen, Bichlien H. ...
Proceedings of the 2020 ACM Designing Interactive Systems Conference,
07/2020
Conference Proceeding
Year-round ultraviolet exposure silently causes skin damage that goes unnoticed until sunburn. Current personal wearables for monitoring UV exposure have not seen significant uptake, which may be ...attributed to their one-size-fits-all aesthetic or inapplicability to people with different skin tones. We present EcoPatches, inkjet-printable chemical patches that mediate a person's relationship with their environment by allowing them to create designs and formulations that resonate with them. Supporting human- and machine-interpretability for EcoPatches' visual changes means that users can glance at their EcoPatch during the day to see large exposure changes or take a picture of their EcoPatch with a smartphone app for more accurate and precise readings. We conducted an online survey to elicit visual design recommendations that support these features. We also evaluated both interpretation methods, finding that they achieved strong Pearson correlation coefficients with the \projectnames' known exposure levels (human: 0.79, app: 0.90).
In this paper, our proposal consists of incorporating frailty into a statistical methodology for modeling time-to-event data, based on non-proportional hazards regression model. Specifically, we use ...the generalized time-dependent logistic (GTDL) model with a frailty term introduced in the hazard function to control for unobservable heterogeneity among the sampling units. We also add a regression in the parameter that measures the effect of time, since it can directly reflect the influence of covariates on the effect of time-to-failure. The practical relevance of the proposed model is illustrated in a real problem based on a data set for downhole safety valves (DHSVs) used in offshore oil and gas production wells. The reliability estimation of DHSVs can be used, among others, to predict the blowout occurrence, assess the workover demand and aid decision-making actions.
We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance ...started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process.
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