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121.
Yimin Ge Mario A. Luna Daniel F. Cowan Luan D. Truong Alberto G. Ayala 《Annals of diagnostic pathology》2009,13(6):384-389
Because thyrolipoma (adenolipoma of thyroid) and thyrolipomatosis (diffuse lipomatosis of thyroid) are distinctively rare conditions with only few cases reported in the literature, we are reporting 5 additional cases. All the 5 patients were adult females, with ages from 38 to 79 years, who presented with thyroid masses. Four of the patients had normal thyroid function tests and one had mild hypothyroidism. All patients received partial or total thyroidectomy. The thyroid specimens showed either circumscribed yellow-tan masses (cases 1, 2, and 3) or diffuse yellow-brown discoloration (cases 4 and 5). Histologic examination revealed abundant mature fat infiltrating the affected thyroid tissue in 3 distinct patterns: (1) fat infiltration limited to follicular adenomas (thyrolipoma); (2) fat diffusely infiltrating throughout the thyroid gland (thyrolipomatosis); or (3) fat infiltration involving both follicular adenoma and their surrounding thyroid tissue. Because of the rarity of thyroid fat-containing lesions, confusion in differential diagnosis may occasionally occur. It is important to be aware during frozen section that these lesions may present as extrathyroidal nodules, which can be radioactive on intraoperative scan for parathyroid glands. In addition, a papillary thyroid carcinoma was also identified in one case of thyrolipomatosis. All patients recovered well after surgery and there has been no recurrence of the lesions after 1 to 24 years of clinical follow-up. In summary, we are reporting 5 rare cases of thyrolipoma and thyrolipomatosis with distinct histologic patterns. Previously reported cases of thyrolipomatosis were reviewed and analyzed with the current cases. 相似文献
122.
Schultsz C Vien le M Campbell JI Chau NV Diep TS Hoang NV Nga TT Savelkoul P Stepnieuwska K Parry C Hien TT Farrar JJ 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2007,101(5):484-492
Studying the antimicrobial drug resistance of nasopharyngeal or nasal carriage isolates of Streptococcus pneumoniae in children is likely to have predictive potential for invasive isolates. Streptococcus pneumoniae nasal carriage was studied in 1422 Vietnamese children. Forty-six percent of 536 isolates showed reduced susceptibility to penicillin and 7% showed intermediate susceptibility to ceftriaxone; and 50% of 518 isolates showed resistance to erythromycin. All isolates were sensitive to levofloxacin and gatifloxacin. Urban and suburban children were significantly more likely to carry drug-resistant isolates than rural children. Rates of non-susceptibility to penicillin and erythromycin increased significantly in the rural province Khanh Hoa in 2003/2004 compared with rates obtained in 1997. An emerging clone of penicillin non-susceptible S. pneumoniae of serogroup 15 was identified, which was widely distributed in addition to the pandemic clones Spain(23F)-1 and Taiwan(19F)-14. Although resistance to fluoroquinolones was not observed, 6 (18%) of 34 isolates had a Lys137Asn mutation in the parC gene. This study shows that drug resistance is increasing in carriage isolates of S. pneumoniae in rural areas in Vietnam owing to spread of pandemic and emerging resistant clones. 相似文献
123.
Justin Bubola Klieb Hagen Nick Blanas Ilan Weinreb Brendan C. Dickson Tra Truong 《Head and neck pathology》2021,15(1):319
Ectomesenchymal chondromyxoid tumor is a rare neoplasm of uncertain histogenesis that typically occurs in the anterior dorsal tongue. Recent reports in the literature have described rare examples of gingival, palatal and tonsillar lesions. Histologically, ectomesenchymal chondromyxoid tumors are typically well-circumscribed, lacking overtly aggressive features. Herein we report a tumor arising in the right mandible that is morphologically and molecularly consistent with ectomesenchymal chondromyxoid tumor. This case furthers awareness of the extra-glossal distribution of this neoplasm; moreover, it suggests that a subset of these tumors have the potential for locally aggressive behaviour.Electronic supplementary materialThe online version of this article (10.1007/s12105-020-01169-5) contains supplementary material, which is available to authorized users. 相似文献
124.
To study the importance of prostatic involvement by transitional cell carcinoma (TCC) in patients with bladder cancer, we examined the entire prostates by whole-mount sections from 214 radical cystoprostatectomy specimens for detailed patterns of involvement by TCC and correlated the results with lymph node metastasis and patients' survival. Prostatic involvement by TCC was detected in 69 (32%) of 214 cases. Among them, 30 (43%) patients had carcinoma in situ (CIS) and the other 39 (57%) were invasive TCC. Carcinoma in situ occurred in either prostatic urethra (n = 6, 20%) or, more commonly, in prostatic ducts/acini (n = 14, 47%), and in a combination of prostatic urethra and ducts (n = 10, 33%). Ten (26%) of the invasive TCC resulted from direct penetration from the primary tumor in the bladder, and the remaining 29 (72%) cases arose from prostatic urethra/ducts, of which 11, 13, and 5 invaded the lamina propria, prostatic stroma, and periprostatic or seminal vesical tissue, respectively. Both prostatic TCC involvement and nodal metastasis were highly significant prognostic factors for patients' survival and the survival significance of prostatic TCC involvement still existed regardless of lymph node status. Furthermore, the presence of prostatic CIS and degrees of prostatic invasion are associated with nodal metastasis and survival. Patients with prostatic CIS or urethral lamina propria invasion had a similar, but higher incidence of lymph node metastasis and lower long-term and 5-year survival than those patients without prostatic involvement. Similarly, prostatic stromal invasion and periprostatic/seminal vesical invasion had a similar, but much higher nodal metastasis and worse survival than patients with only prostatic CIS or urethral lamina propria invasion. In summary, presence of prostatic TCC involvement and levels of involvement are significant prognostic factors in patients with bladder cancer. 相似文献
125.
126.
Jack D. Moreland Steven Westland Vien Cheung Steven J. Dain 《Ophthalmic & physiological optics》2010,30(5):685-692
The claims made for 43 commercial filter ‘aids’, that they improve the colour discrimination of red‐green colour defectives, are assessed for protanomaly and deuteranomaly by changes in the colour spacing of traffic signals (European Standard EN 1836:2005) and of the Farnsworth D15 test. Spectral transmittances of the ‘aids’ are measured and tristimulus values with and without ‘aids’ are computed using cone fundamentals and the spectral power distributions of either the D15 chips illuminated by CIE Illuminant C or of traffic signals. Chromaticities (l,s) are presented in cone excitation diagrams for protanomaly and deuteranomaly in terms of the relative excitation of their long (L), medium (M) and short (S) wavelength‐sensitive cones. After correcting for non‐uniform colour spacing in these diagrams, standard deviations parallel to the l and s axes are computed and enhancement factors El and Es are derived as the ratio of ‘aided’ to ‘unaided’ standard deviations. Values of El for traffic signals with most ‘aids’ are <1 and many do not meet the European signal detection standard. A few ‘aids’ have expansive El factors but with inadequate utility: the largest being 1.2 for traffic signals and 1.3 for the D15 colours. Analyses, replicated for 19 ‘aids’ from one manufacturer using 658 Munsell colours inside the D15 locus, yield El factors within 1% of those found for the 16 D15 colours. 相似文献
127.
Dinh Hieu Truong Thi Chinh Ngo Nguyen Thi Ai Nhung Duong Tuan Quang Thi Le Anh Nguyen Dorra Khiri Sonia Taamalli Florent Louis Abderrahman El Bakali Duy Quang Dao 《RSC advances》2022,12(3):1499
Direct and indirect antioxidant activities of rosmarinic acid (RA) based on HOO˙/CH3OO˙ radical scavenging and Fe(iii)/Fe(ii) ion chelation were theoretically studied using density functional theory at the M05-2X/6-311++G(2df,2p) level of theory. First, four antioxidant mechanisms including hydrogen atom transfer (HAT), radical adduct formation (RAF), proton loss (PL) and single electron transfer (SET) were investigated in water and pentyl ethanoate (PEA) phases. Regarding the free radical scavenging mechanism, HAT plays a decisive role with overall rate coefficients of 1.84 × 103 M−1 s−1 (HOO˙) and 4.49 × 103 M−1 s−1 (CH3OO˙) in water. In contrast to PL, RAF and especially SET processes, the HAT reaction in PEA is slightly more favorable than that in water. Second, the [Fe(iii)(H2O)6]3+ and [Fe(ii)(H2O)6]2+ ion chelating processes in an aqueous phase are both favorable and spontaneous especially at the O5, site-1, and site-2 positions with large negative ΔrG0 values and great formation constant Kf. Finally, the pro-oxidant risk of RA− was also considered via the Fe(iii)-to-Fe(ii) complex reduction process, which may initiate Fenton-like reactions forming reactive HO˙ radicals. As a result, RA− does not enhance the reduction process when ascorbate anions are present as reducing agents, whereas the pro-oxidant risk becomes remarkable when superoxide anions are found. The results encourage further attempts to verify the speculation using more powerful research implementations of the antioxidant activities of rosmarinic acid in relationship with its possible pro-oxidant risks.Direct and indirect antioxidant activities of rosmarinic acid (RA) based on HOO˙/CH3OO˙ radical scavenging and Fe(iii)/Fe(ii) ion chelation were theoretically studied using density functional theory at the M05-2X/6-311++G(2df,2p) level of theory. 相似文献
128.
129.
Jan D. Andersson Nicholas Seneca Phong Truong David Wensbo Patrick Raboisson Lars Farde Christer Halldin 《Nuclear medicine and biology》2013,40(4):547-553
IntroductionThe aims of the present positron emission tomography (PET) study were to set up a system for 11C-cyanation labeling of the selective mGluR5-antagonist [11C]AZD9272 and to perform the first in vivo characterization of [11C]AZD9272 binding in cynomolgus monkeys.Methods[11C]AZD9272 was labeled using palladium mediated 11C-cyanation. Altogether seven PET measurements were performed in three cynomolgus monkeys including baseline and co-injection experiments with unlabelled AZD9272 (0.04 and 0.4 mg/kg). Radiometabolites in plasma were measured using HPLC.Results[11C]AZD9272 was prepared in over 50% incorporation yield from hydrogen [11C]cyanide in a total synthesis time of 45–50 min. The radiochemical purity of the radioligand in its final formulation was high (> 99%) and the mean specific radioactivity was 47 GBq/ μmol (1278 Ci/mmol, n = 7) calculated at end of bombardment (EOB). In the baseline measurements 10% of the total injected radioactivity was present in monkey brain at five minutes after i.v. injection. The radioactivity concentration was high in the caudate, cingulate gyrus and thalamus whereas it was moderate in the temporal cortex and lower for the cerebellum. After co-injection with cold AZD9272 the binding of [11C]AZD9272 was reduced in a dose-dependent fashion. Analysis of radiometabolites showed relatively slow metabolism and resulted only in hydrophilic radiometabolites.ConclusionA fast and efficient method was developed to label AZD9272 with 11C. PET-examination in Cynomolgus monkeys showed that [11C]AZD9272 entered the brain to a high extent, that binding was saturable and that the regional radioactivity pattern was in accordance with the known distribution of mGluR5. The results support further examination of [11C]AZD9272 binding in human subjects. 相似文献
130.