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991.
Colorectal cancer (CRC) can be divided into non-mucinous and mucinous subtypes, of which the latter portends to have a worse clinical prognosis. A previous study suggested a putative link between SOX2 expression observed selectively in mucinous CRC and the induction of the gastric mucin MUC5AC. In this study, we re-evaluated the expression behavior of SOX2, MUC5AC, and CDX2 in both types of CRC. We performed immunohistochemical analysis on 90 cases of non-mucinous CRCs, 57 cases of mucinous CRCs, and 15 case-matched normal intestinal mucosa. In contrast to the previously suggested link between SOX2 and mucinous CRC, we observe aberrant expression of SOX2 at equal levels in both subtypes. Fluorescence in situ hybridization (FISH) analysis shows that expression is not attributed to genomic amplification. While SOX2 and CDX2 are normally expressed in a reciprocal manner, SOX2-positive tumor cells co-express CDX2. Furthermore, we show that MUC5AC is expressed independently of SOX2. In conclusion, we show that aberrant SOX2 expression is specifically linked neither to mucinous CRCs nor to the induction of MUC5AC, in contrast to previous suggestions.  相似文献   
992.
993.
The purpose of the present study was to investigate whether the size of the opening in the zona pellucida (ZP) of human single pronuclear (1PN) oocytes made by laser and partial zona dissection (PZD) techniques might interfere with the survival and subsequent development to blastocyst stage upon vitrification and warming. Moreover, the viability of these blastocysts was evaluated by comparing their total cell number (TCN) to the TCN of blastocysts developed from control non-vitrified zona-intact 1PN oocytes. Prior to vitrification, a total of 97 and 88 1PN oocytes were subjected to polar body biopsy using laser-assisted and PZD techniques, respectively. The size of ZP opening made by laser and PZD techniques did not interfere with survival (94.8% and 95.4%) or development to the blastocyst stage (27.8% and 26.1%). However, the TCN of laser-derived blastocysts was significantly lower than the TCN of blastocysts developed from non-vitrified control 1PN oocytes (48.7 ± 3.4 versus 70.8 ± 7.1, P < 0.028). The vitrification protocol used here is thus revealed to be an effective method for cryopreservation of 1PN oocytes following polar body biopsy. However, the viability of blastocysts developed from laser-treated 1PN oocytes seems to be negatively affected by this method of biopsy.  相似文献   
994.
IntroductionAndrogen deprivation therapy (ADT) is frequently used in the treatment of prostate cancer worldwide. Variable testosterone (T) recovery profiles after ADT cessation have been cited.AimTo evaluate T recovery after cessation of ADT.MethodsWe reviewed our institutional prospectively maintained database of patients with prostate cancer who received ADT. Serum early morning total T (TT) levels, collected at baseline and periodically after ADT cessation, were analyzed. Patient age, baseline T level, duration of ADT, and presence of diabetes and sleep apnea were selected as potential predictors of T recovery. 3 metrics of T recovery after 24 months of ADT cessation were analyzed: return to non-castrate level (TT > 50 ng/dL), return to normal (T > 300 ng/dL), and return back to baseline level (BTB). Multivariable time-to-event analysis (Cox proportional hazards), χ2 test, logistic regression model, and Kaplan-Meier curve were performed to define impact of the above predictors on time and chance of T recovery.Main Outcome MeasuresTime and chance of T recovery to non-castrate level (TT > 50 ng/dL), return to normal (T > 300 ng/dL), and return BTB.Results307 men with a mean age of 65 ± 8 years were included. Mean duration of ADT was 17 ± 25 months, and median follow-up was 31 ± 35 months. Mean TT values were 379 ng/dL at baseline and 321 ng/dL at >24 months. At 24 months after cessation of ADT, 8% of men remained at castrate level, 76% returned to TT >300 ng/dL, and 51% had returned BTB. Lower baseline T levels (TT < 400 ng/dL) and ADT duration >6 months were associated with a lower likelihood of recovery to normal TT at 24 months. Age >65 years and receiving ADT for >6 months were significantly associated with a slower T recovery.Clinical ImplicationsT recovery after ADT is not certain and may take longer than expected. Considering the range of side effects of low T, we believe that these findings must be discussed with patients before initiating such therapies.Strengths & LimitationsOur strengths consisted of a relatively large database, long follow-up, and clinically meaningful endpoints. Limitations included the retrospective design of the study.ConclusionT recovery rates after ADT cessation vary according to patient age, ADT duration, and baseline T levels. Approximately one-quarter of patients failed to normalize their TT level, and one-tenth of men remained at castrate levels 24 months after ADT cessation.Nascimento B, Miranda EP, Jenkins LC, et al. Testosterone Recovery Profiles After Cessation of Androgen Deprivation Therapy for Prostate Cancer. J Sex Med 2019;16:872–879.  相似文献   
995.
Objective: In contrast with combined hormonal contraception, progestin-only contraception is not associated with an increase in venous thromboembolism or stroke. Women with migraine are at increased risk of ischaemic stroke. Several studies have reported a reduction in migraine frequency and intensity with desogestrel 75 µg, a progestin-only pill. At present the quality of data is limited by retrospective study designs, lack of control groups and small sample sizes. We present the first prospective nonrandomised controlled trial.

Methods: A total of 150 women with migraine visiting our clinic for contraceptive counselling were screened. The intervention group comprised women who opted for contraception with desogestrel (n?=?98); the control group comprised women who continued their usual contraceptive (n?=?36). Participants completed daily diaries for 90 days before the intervention and 180 days after the intervention.

Results: In the intervention group, we found improvements in migraine frequency (p?<?.001), migraine intensity (p?<?.001) and the number of triptans used (p?<?.001). These improvements were already significant after 90 days of desogestrel use (p?<?.001). Disability scores also decreased significantly. No improvement was seen in the nonintervention group.

Conclusion: These data demonstrate for the first time in a prospective controlled setting that daily use of the progestin desogestrel is associated with a decrease in migraine frequency, migraine intensity and pain medication use in women with migraine, with and without aura, who had previously been experiencing at least three days of migraine per month.

Trial registration: The study is registered in the University of Zürich database (www.research-projects.uzh.ch/unizh.htm).  相似文献   

996.

Research question

Conventional treatments are often associated with adverse effects and endometriosis pain symptoms may reoccur despite treatment. Consequently, many women use complementary health approaches (CHA) and home remedies (HR) to relieve their pain. The aim of this study was to examine the frequency and the subjectively perceived efficacy of CHA/HR use by women affected by endometriosis.

Design

Retrospective evaluation using medical charts and a questionnaire. Women recruited in hospitals and in self-help groups were asked about the use of ‘topical heat’, ‘repose/relaxation’, ‘movement/massages’, ‘homeopathy/phytotherapy’, ‘acupuncture/traditional Chinese medicine (TCM)’ and ‘kinesiology/physiotherapy’.

Results

From a total of 574 women with a confirmed diagnosis of endometriosis, 359 (62.5%) applied some form of CHA/HR. Women suffering from fatiguing disease symptoms more often selected alternative therapies (odds ratio [OR] 3.14, 95% confidence interval [CI] 1.39–7.11, P?=?0.006) compared with women without these characteristics. Furthermore, women dissatisfied with healthcare provided by their treating physician, more frequently (OR 2.30, 95% CI 1.19–4.45, P?=?0.013) chose the aforementioned alternative strategies.

Conclusion

As conventional therapies may not be sufficiently effective, women's needs should be closely examined, and individual treatment options should be discussed and initiated by clinicians to provide the best comprehensive treatment possible for endometriosis.  相似文献   
997.

Research question

Does mode of conception influence placental volume and other first-trimester outcomes?

Design

This retrospective single-centre case-control study led in Dijon University Hospital included 252 singleton pregnancies (84 IVF with either fresh embryo transfer or frozen-thawed embryo transfer [FET] and 168 natural conceptions). First-trimester placental volume, uterine artery pulsatility index and maternal serum PAPP-A and beta-HCG were measured. Statistical analyses were adjusted for gestational age, the newborn’s gender, maternal age, parity, body mass index and smoking status.

Results

Placental volume was significantly greater in the FET group than in the control group (P?=?0.043) and fresh embryo transfer (P?=?0.023) groups. At birth, fresh embryo transfer newborns were significantly smaller than controls (P?=?0.01) and FET newborns (P?=?0.008). Postpartum haemorrhage was far more frequent in FET than in controls and fresh embryo transfer group (38.1%, 2.6% and 1.9%, respectively; P < 0.0001). Placental volume positively correlated with PAPP-A, beta-HCG and the newborn’s birth weight, and negatively correlated with uterine artery pulsatility index.

Conclusions

Placental volume and other first-trimester parameters are modified by IVF with fresh embryo transfer and FET compared with natural conception, but with opposite trends. Given the different protocols used for these techniques, hormonal treatment per se may have a major effect on pregnancy outcomes through the modification of placental invasiveness.  相似文献   
998.
Deficiency of the muscle isozyme of glycogen phosphorylase is causative of McArdle disease or Glycogen storage disease type V (GSD-V), the most common autosomal recessive disorder of glycogen metabolism. The typical clinical presentation is characterized by exercise intolerance with cramps, and recurrent myoglobinuria. To date, 46 mutations in the PYGM gene have been detected in GSD-V patients. We report the mutational spectrum in 68 Italian patients. We identified 30 different mutations in the PYGM gene, including 19 mutations that have not been reported previously. The novel mutations include: eight missense mutations (c.475G>A, p.G159R; c.689C>G, p.P230R; c.1094C>T, p.A365E; c.1151C>A, p.A384D; c.1182C>T, p.R428C; c.1471C>T, p.R491C; c.2444A>C, p.D815A; c.2477G>C, p.W826S), two nonsense mutations (c.1475G>A, p.W492X; c.1627A>T, p.K543X), five splice site mutations (c.855 +1G>C; c.1092 +1G>A; c. 1093-1G>T; c.1239 +1G>A; c.2380 +1G>A), and four deletions (c.715_717delGTC, p.V239del; c.304delA, p.N102DfsX4; c.1970_2177del, p.V657_G726; c.2113_2114delGG, p.G705RfsX16). Whereas we confirmed lack of direct correlation between the clinical phenotype and the genotype, we also found that the so-called 'common mutation' (p.R50X) accounted for about 43% of alleles in our cohort and that no population-related mutations are clearly identified in Italian patients.  相似文献   
999.
T‐cell polyspecificity, predicting that individual T cells recognize a continuum of related ligands, implies that multiple antigens can tolerize T cells specific for a given self‐antigen. We previously showed in C57BL/6 mice that part of the CD4+ T‐cell repertoire specific for myelin oligodendrocyte glycoprotein (MOG) 35–55 also recognizes the neuronal antigen neurofilament medium (NF‐M) 15–35. Such bi‐specific CD4+ T cells are frequent and produce inflammatory cytokines after stimulation. Since T cells recognizing two self‐antigens would be expected to be tolerized more efficiently, this finding prompted us to study how polyspecificity impacts tolerance. We found that similar to MOG, NF‐M is expressed in the thymus by medullary thymic epithelial cells, a tolerogenic population. Nevertheless, the frequency, phenotype, and capacity to transfer experimental autoimmune encephalomyelitis (EAE) of MOG35‐55‐reactive CD4+ T cells were increased in MOG‐deficient but not in NF‐M‐deficient mice. We found that presentation of NF‐M15‐35 by I‐Ab on dendritic cells is of short duration, suggesting unstable MHC class II binding. Consistently, introducing an MHC‐anchoring residue into NF‐M15‐35 (NF‐M15‐35T20Y) increased its immunogenicity, activating a repertoire able to induce EAE. Our results show that in C57BL/6 mice bi‐specific encephalitogenic T cells manage to escape tolerization due to inefficient exposure to two self‐antigens.  相似文献   
1000.
Primary ciliary dyskinesia (PCD) is an autosomal recessive disease characterized by chronic respiratory infections of the upper and lower airways, hypofertility, and, in approximately half of the cases, situs inversus. This complex phenotype results from defects in motile cilia and sperm flagella. Among the numerous genes involved in PCD, very few—including CCDC39 and CCDC40—carry mutations that lead to a disorganization of ciliary axonemes with microtubule misalignment. Focusing on this particular phenotype, we identified bi‐allelic loss‐of‐function mutations in GAS8, a gene that encodes a subunit of the nexin‐dynein regulatory complex (N‐DRC) orthologous to DRC4 of the flagellated alga Chlamydomonas reinhardtii. Unlike the majority of PCD patients, individuals with GAS8 mutations have motile cilia, which, as documented by high‐speed videomicroscopy, display a subtle beating pattern defect characterized by slightly reduced bending amplitude. Immunofluorescence studies performed on patients’ respiratory cilia revealed that GAS8 is not required for the proper expression of CCDC39 and CCDC40. Rather, mutations in GAS8 affect the subcellular localization of another N‐DRC subunit called DRC3. Overall, this study, which identifies GAS8 as a PCD gene, unveils the key importance of the corresponding protein in N‐DRC integrity and in the proper alignment of axonemal microtubules in humans.  相似文献   
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