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71.
Familial Mediterranean fever (FMF) is caused by mutations in the MEFV gene and the spectrum of mutations among Greek–Cypriots with FMF‐related symptoms was examined. Sequence analysis for exons 2, 3, 5, and 10 of the MEFV gene was performed in a cohort of 593 patients. A total of 70 patients carried mutations in the homozygote or compound heterozygote state, 128 were identified with one MEFV mutation and 395 had no mutations. Of the 268 identified alleles, p.Val726Ala (27.61%) was the most frequent followed by p.Met694Val (19.40%). The missense mutations p.Arg761His (3.73%) and p.Ala744Ser (2.24%) were identified as the rarest. An interesting finding is the high frequency (18.28%) of the complex p.Phe479Leu–p.Glu167Asp that was identified in 49 of the mutated alleles. The MEFV genotypes did not follow a binomial distribution and proved not to satisfy the HWE (P < 0.001). The high percentage (66.61%) of patients with unidentified mutations could be due to mutations in the rest of the coding or noncoding MEFV gene or due to mutations in other genes that are also causing Hereditary Recurrent Fevers. Results from this work indicate the high incidence of FMF in Cyprus and describe the spectrum of the mutations which occur in the country.  相似文献   
72.
Endogenous mechanisms that act in the resolution of acute inflammation are essential for host defense and the return to homeostasis. Resolvin D1 (RvD1), biosynthesized during resolution, displays potent and stereoselective anti-inflammatory actions, such as limiting neutrophil infiltration and proresolving actions. Here, we demonstrate that RvD1 actions on human polymorphonuclear leukocytes (PMNs) are pertussis toxin sensitive, decrease actin polymerization, and block LTB4-regulated adhesion molecules (β2 integrins). Synthetic [3H]-RvD1 was prepared, which revealed specific RvD1 recognition sites on human leukocytes. Screening systems to identify receptors for RvD1 gave two candidates—ALX, a lipoxin A4 receptor, and GPR32, an orphan—that were confirmed using a β-arrestin-based ligand receptor system. Nuclear receptors including retinoid X receptor-α and peroxisome proliferator-activated receptor-α, -δ, -γ were not activated by either resolvin E1 or RvD1 at bioactive nanomolar concentrations. RvD1 enhanced macrophage phagocytosis of zymosan and apoptotic PMNs, which increased with overexpression of human ALX and GPR32 and decreased with selective knockdown of these G-protein-coupled receptors. Also, ALX and GPR32 surface expression in human monocytes was up-regulated by zymosan and granulocyte-monocyte–colony-stimulating factor. These results indicate that RvD1 specifically interacts with both ALX and GPR32 on phagocytes and suggest that each plays a role in resolving acute inflammation.  相似文献   
73.
Suppressor of cytokine signaling 3 (SOCS3) is a negative regulator of granulocyte-colony stimulating factor (G-CSF) signaling in vivo. SOCS proteins regulate cytokine signaling by binding, via their SH2 domains, to activated cytokine receptors or their associated Janus kinases. In addition, they bind to the elongin B/C ubiquitin ligase complex via the SOCS box. To ascertain the contribution of the SOCS box of SOCS3 to in vivo regulation of G-CSF signaling, we generated mice expressing a truncated SOCS3 protein lacking the C-terminal SOCS box (SOCS3(Delta SB/Delta SB)). SOCS3(Delta SB/Delta SB) mice were viable, had normal steady-state hematopoiesis, and did not develop inflammatory disease. Despite the mild phenotype, STAT3 activation in response to G-CSF signaling was prolonged in SOCS3(Delta SB/Delta SB) bone marrow. SOCS3(Delta SB/Delta SB) bone marrow contained increased numbers of colony-forming cells responsive to G-CSF and IL-6. Treatment of the mice with pharmacologic doses of G-CSF, which mimics emergency granulopoiesis and therapeutic use of G-CSF, revealed that SOCS3(Delta SB/Delta SB) mice were hyperresponsive to G-CSF. Compared with wild-type mice, SOCS3(Delta SB/Delta SB) mice developed a more florid arthritis when tested using an acute disease model. Overall, the results establish a role for the SOCS box of SOCS3 in the in vivo regulation of G-CSF signaling and the response to inflammatory stimuli.  相似文献   
74.
OBJECTIVE: To determine criteria for a clinically significant vein stenosis with duplex ultrasound (DU) in patients with signs and symptoms of central venous outflow obstruction. METHODS: Patients referred with swelling with or without pain to the vascular laboratory to detect vein obstruction were evaluated. These were mostly patients who had liver transplant, dialysis access, and tumors. All patients had DU prior to any other imaging. Only patients who subsequently underwent phlebography with intention to treat the vein stenosis were included in the study. A phlebogram with two views, pressure measurements across the stenosis, and intravascular ultrasound in selected cases were performed in all patients with suspected stenosis on DU. Adjacent ipsilateral normal vein segments were utilized as controls. The invasive tests were performed within 2 weeks of the DU. Follow-up was performed with DU at discharge and within 6 months of the procedure. A pressure gradient of =3 mm Hg across the stenosis was used to define a >50% diameter reduction, which was also determined by phlebographic measurement. RESULTS: Thirty-seven patients, 20 males and 17 females, mean age 54 years, range 27 to 79, were evaluated. Forty-one stenotic venous sites were detected with DU; inferior vena cava 14, superior vena cava 2, portal 2, iliac 11, common femoral 3, brachiocephalic 3, subclavian 5, and axillary vein 1. Phlebography identified 37 of these stenoses and demonstrated two more not seen by DU. Pressure measurements confirmed 39 of those detected by DU. The best criterion by DU to detect a >50% stenosis was a poststenotic to pre-stenotic peak vein velocity ratio of 2.5. The presence of poststenotic turbulence and planimetric calculations of the diameter reduction increased the diagnostic confidence but not the accuracy. Using the pressure gradient of >/=3 mm Hg as a reference test, there were two false positive and two false negative exams with DU, while phlebography had two false negative exams. The overall agreement of DU alone was 90% of phlebography >95% and when combined 100%. Intravascular ultrasound identified correctly all 11 lesions in 11 patients. After angioplasty and stenting, there was a dramatic reduction in the edema in most patients particularly in those that had a caval stenosis. Restenosis was identified by DU in 5/29 (17%) patients at 6 months that were confirmed by phlebography and pressure measurements. Reintervention was performed in four and it was successful in three. CONCLUSIONS: DU is a sensitive method to identify a clinically significant vein stenosis. A peak vein velocity ratio of >2.5 across the stenosis is the best criterion to use for the presence of a pressure gradient of =3 mm Hg. DU can be used to select patients for intervention and also to monitor the success of the treatment during follow-up.  相似文献   
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Analysis of germline p53 mutations in breast cancer reveals that the Li-Fraumeni and Li-Fraumeni-like syndromes are mostly related to the loss of initiation codon 133 of regulatory TP53 isoforms (Delta133p53). In eight codons of exons 5-8 (including 133), mutations are frequent in Li-Fraumeni-related, but scarce in sporadic breast cancer, while in six more codons they are frequent both in familial and sporadic breast cancers. At the proximity of these codons, we observed in somatic mutation databases, 16 codons (minihotspots mostly in exons 7, 8) which undergo frequent G:C > A:T transitions (non-CpG) in all sporadic cancers. In addition, in sporadic breast cancer we observed 35 adjacent codons in which the following types of mutation are observed: frequent G:C > A:T transitions at CCs/GGs, frequent silent mutations in exons 5,6 and suppressed nonsense mutations (5 codons, few records). Non-CpG G:C > A:T transitions in the 35 codons are rare in familial cancers (p53, BRCA1, or BRCA2-related), but frequent in sporadic cancers in organs where Li-Fraumeni-related carcinogenesis is common e.g. adrenal cortex, soft tissues. These data are in support of the following tissue-specific processes: in sporadic breast cancer (sarcomas etc.), loss of methylation sites (in 35 codons mostly next to codon 133), might lead to loss of silencing of TP53 isoforms which are suppressed in these tissues. On the contrary, "spreading" of cytosine methylation (asymmetric) in a G:C-rich region next to common hotspots (codons 238-252 in minihotspots) and mutagenesis probably destabilizes all tissues. Frequent C > T activation at non-CpG is also observed in prostate sporadic cancer, which similarly to breast, undergoes age-related crisis. The above data reveal that tissue-specific epigenetic regulatory mechanisms might be involved in p53 instability.  相似文献   
77.
Recent preclinical and clinical data have suggested the potential benefit of photodynamic therapy (PDT) in the treatment of periodontitis. However, currently, there are very limited data from controlled clinical trials evaluating the effect of PDT in the treatment of periodontitis. The aim of the present study was to evaluate the clinical and microbiological effects of the adjunctive use of PDT in non-surgical periodontal treatment in patients receiving supportive periodontal therapy. Twenty-four patients receiving regularly supportive periodontal therapy were randomly treated with either subgingival scaling and root planing followed by a single episode of PDT (test) or subgingival scaling and root planing alone (control). The following parameters were evaluated at baseline and at 3 months and 6 months after therapy: full mouth plaque score (FMPS), full mouth bleeding score (FMBS), bleeding on probing (BOP) at experimental sites, probing pocket depth (PPD), gingival recession (REC), and clinical attachment level (CAL). Primary outcome variables were changes in PPD and CAL. Microbiological evaluation of Aggregatibacter actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), Prevotella intermedia (P.i.), Tannerella forsythensis (T.f.), Treponema denticola (T.d.), Peptostreptococcus micros (P.m.), Fusobacterium nucleatum (F.n.), Campylobacter rectus (C.r.), Eubacterium nodatum (E.n.), Eikenella corrodens (E.c.), and Capnocytophaga species (C.s.) was also performed at baseline and at 3 months and 6 months after therapy, using a commercially available polymerase chain reaction test. No differences in any of the investigated parameters were observed at baseline between the two groups. At 3 months and 6 months after treatment, there were no statistically significant differences between the groups in terms of PPD, CAL and FMPS. At 3 months and 6 months, a statistically significantly higher improvement of BOP was found in the test group. At 3 months after therapy, the microbiological analysis showed a statistically significant reduction of F.n. and E.n. in the test group. At 6 months, statistically significantly higher numbers of E.c. and C.s. were detected in the test group. The additional application of a single episode of PDT to scaling and root planing failed to result in an additional improvement in terms of PPD reduction and CAL gain, but it resulted in significantly higher reduction of bleeding scores than following scaling and root planing alone.  相似文献   
78.
Propylthiouracil (PTU) has been held responsible for diffuse alveolar hemorrhage (DAH) with positive antineutrophil cytoplasmic antibody (ANCA) and capillaritis. We describe a case of a 23-year-old pregnant female with Grave's disease treated with PTU who presented with flu-like symptoms and progressive dyspnea. Open lung biopsy showed DAH without evidence of capillaritis. All serologies were negative. Five days after PTU withdrawal and intravenous steroid therapy, the patient improved dramatically. She remained symptom free without relapse 9 months after the episode. To the best of our knowledge, this is the first reported case of PTU-related alveolar hemorrhage with negative serologic markers and without capillaritis.  相似文献   
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