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31.

Objective

To present current guidelines regarding treatment of mastocytosis in pregnancy on the example of observed patients.

Design

Case control national study.

Setting

Polish Center of the European Competence Network on Mastocytosis (ECNM).

Population or Sample

23 singleton spontaneous pregnancies in 17 women diagnosed with mastocytosis in years 1999–2014, before becoming pregnant.

Methods

Prospective analysis outcomes of pregnancies and deliveries.

Main Outcome Measures

Survey developed in cooperation with the Spanish Instituto de Estudios de Mastocitosis de Castilla-La Mancha (CLMast), Hospital Virgen del Valle, Toledo, Red Espańola de Mastocitosis (REMA), Spain.

Results

All 23 pregnancies resulted from natural conception. Obstetrical complications recorded in the first trimester included spontaneous miscarriage (5 pregnancies). Four patients delivered preterm, including one delivery due to preeclampsia at 26 weeks which resulted with neonate death due to extreme prematurity. Five women delivered via cesarean: four due to obstetrical indications and one due to mastocytosis, during which no anesthesia related complications were recorded. Of patients delivering vaginally, two received extradural anesthesia, three required oxytocin infusion due to uterine hypotonia. No labor complications were recorded. In one woman with pregnancy-induced hypertension, early puerperium was complicated by the presence of persistent arterial hypertension. One neonate was born with the signs of cutaneous mastocytosis. Another neonate was diagnosed with Patau syndrome. Four women were treated for mastocytosis prior to conception and continued therapy after becoming pregnant. One patient was put on medications in the first trimester due to worsening of her symptoms. Pregnancy exerted only a slight effect on the intensity and frequency of mastocytosis-related symptoms observed. Worsening of the disease-related symptoms was documented in only four patients (23%). None of the patients showed the signs of anaphylaxis, either before becoming pregnant, or during pregnancy and puerperium.

Conclusions

There is no contraindication to pregnancy when mastocystosis-related pathologies are under appropriate medical control.  相似文献   
32.
Pastures in the Appalachian region of the United States comprise a mix of grasses, legumes and forbs that tend to differ in productivity within and among years. A high degree of spatial variability in hill‐land pasture creates microsite conditions that influence botanical composition of pasture. The variation in sward composition presents logistical challenges to livestock producers who rely on a dependable supply of herbage mass and nutritive value to meet production goals. Our objective was to determine if forage communities sown for specific functions, for example, superior dry matter productivity, resource patch exploitation or targeted seasonal production, adapted to changing growing conditions within and among years. Productivity of communities differed among years reflecting the cumulative influences of time, ontogenetic and environmental variations. Maximum productivity was influenced by the specific forage community and less so by simple clipping and fertiliser management. Naturalised swards clipped to emulate hay management tended to have sustained herbage productivity but lower nutritive value when compared to sown communities. Rankings of dry matter productivity of communities were similar for each year where bioactive composition, high productivity and warm season tended to produce the most, and stoloniferous‐rhizomatous and naturalised pasture the least. Regardless of initial sward composition, effective number of species as an index of diversity increased when frequently clipped swards were not fertilised, and when infrequently clipped swards were fertilised. Dry matter production patterns were not influenced by the effective number of species in any forage community suggesting that key species sustained productivity with volunteer species making lesser contribution to total productivity. The species composition of forage plant communities appears to be more important than clipping or fertiliser management practices as a means to sustain forage productivity.  相似文献   
33.
Two new species of the orchid genus Quekettia are described. Colombian Quekettia aureliae is distinguished from similar Q. microscopica by the pandurate lip with a pair of small, flap‐like calli in the isthmus between hypo‐ and epichile, and deeply emarginated epichile apex. Quekettia senghasiana found in Guyana resembles Q. papillosa but it is characterized by the free lateral sepals, oblanceolate, obtuse petals and much larger lip which is oblong–obovate in outline and with lip disc being papillate only near the base.  相似文献   
34.
35.
Allostery is one of the most important features of proteins. It greatly contributes to the complexity of life, since it enables possibility of precise tuning of protein function, as well as performing more than one function per protein. Probe dependence is one of the unique features of allostery. It allows a protein to respond differently to the same allosteric modulator when different drugs or transmitters are bound. Unfortunately, allosteric mechanisms are difficult to investigate experimentally. Instead, they can be reproduced artificially in simulations. We simulated in silico a native-like cell membrane fragment with an active-state human μ opioid receptor (MOR) in order to investigate diverse effects of a receptor’s positive allosteric modulator on various agonists. Particular emphasis on native-likeness of the environment was put. We managed to reproduce the experimentally observed effects, which allowed us to take deeper insight into their underlying mechanisms. We found an allosteric pathway in the receptor, leading from the ligand binding site to the intracellular, effector site. We observed that the modulator affected the pathway, inducing different resultant responses for full and partial agonists.  相似文献   
36.
37.
Carrion flower stapeliads are examples of olfactory mimicry, forming sapromyiophilous flowers, which mimic food sources or oviposition sites to attract fly pollinators. The aim of this work was to investigate the ultrastructure of osmophores involved in the release of the carrion odor of Orbea variegata and Boucerosia indica flowers. In spite of their similar architecture (epidermal epithelium+subepidermal secretory layers), the osmophores of stapeliads feature some differences in morphology and ultrastructure. The epidermal epithelial cells of O. variegata and B. indica differ in shape, but both are extremely rich in endoplasmic reticulum and flocculent material in the vacuole. Unlike the Orbea, Boucerosia has starchless leucoplasts in the epidermal epithelium. Orbea features a cuticle with microchannels, while Boucerosia has a different mechanism for the pathway of scent substances to the cell exterior. They are released by rupturing of the outer layer of cuticle at the apex of the papillae. The epidermal cells of the adaxial corolla differ even between parts of the corolla, the corolla lobes and the annulus in the flower. This diversity may be connected with an odor gradient. The morphological and anatomical features of stapeliad (subtribe Stapeliinae) osmophores are generally similar to osmophores of members of subtribe Ceropegiinae (Ceropegia), thus, we suggest that this model of osmophores evolved before early diversification of Ceropegieae. The ultrastructural features of stapeliad osmophores are generally similar to those of Araceae, Orchidaceae and Passifloraceae.  相似文献   
38.
1. Although there is a great deal of theoretical and empirical data about the life history responses of time constraints in organisms, little is known about the latitude‐compensating mechanism that enables northern populations' developmental rates to compensate for latitude. To investigate the importance of photoperiod on development, offspring of the obligatory univoltine damselfly Lestes sponsa from two populations at different latitudes (53°N and 63°N) were raised in a common laboratory environment at both northern and southern photoperiods that corresponded to the sites of collection. 2. Egg development time was shorter under northern photoperiod regimes for both populations. However, the northern latitude population showed a higher phenotypic plasticity response to photoperiod compared with the southern latitude population, suggesting a genetic difference in egg development time in response to photoperiod. 3. Larvae from both latitudes expressed shorter larval development time and faster growth rates under northern photoperiod regimes. There was no difference in phenotypic plastic response between northern and southern latitude populations with regard to development time. 4. Data on field collected adults showed that adult sizes decreased with an increase in latitude. This adult size difference was a genetically fixed trait, as the same size difference between populations was also found when larvae were reared in the laboratory. 5. The results suggest phenotypic plasticity responses in life history traits to photoperiod, but also genetic differences between north and south latitude populations in response to photoperiod, which indicates the presence of a latitudinal compensating mechanism that is triggered by a photoperiod.  相似文献   
39.
Predicting transmembrane beta-barrels in proteomes   总被引:1,自引:0,他引:1  
Very few methods address the problem of predicting beta-barrel membrane proteins directly from sequence. One reason is that only very few high-resolution structures for transmembrane beta-barrel (TMB) proteins have been determined thus far. Here we introduced the design, statistics and results of a novel profile-based hidden Markov model for the prediction and discrimination of TMBs. The method carefully attempts to avoid over-fitting the sparse experimental data. While our model training and scoring procedures were very similar to a recently published work, the architecture and structure-based labelling were significantly different. In particular, we introduced a new definition of beta- hairpin motifs, explicit state modelling of transmembrane strands, and a log-odds whole-protein discrimination score. The resulting method reached an overall four-state (up-, down-strand, periplasmic-, outer-loop) accuracy as high as 86%. Furthermore, accurately discriminated TMB from non-TMB proteins (45% coverage at 100% accuracy). This high precision enabled the application to 72 entirely sequenced Gram-negative bacteria. We found over 164 previously uncharacterized TMB proteins at high confidence. Database searches did not implicate any of these proteins with membranes. We challenge that the vast majority of our 164 predictions will eventually be verified experimentally. All proteome predictions and the PROFtmb prediction method are available at http://www.rostlab.org/ services/PROFtmb/.  相似文献   
40.
OBJECTIVE: To assess angiogenesis and the proliferative activity of bone marrow in patients with chronic lymphocytic leukemia (CLL) in relation to the bone marrow infiltration pattern. STUDY DESIGN: Bone marrow samples were obtained by trephine biopsy from 46 patients with B-cell CLL (B-CLL). Infiltration pattern was diffuse in 20 patients and nondiffuse--i.e., nodular, interstitial or mixed--in the remaining 26 patients. Ten normal bone marrow samples were used as a control group. Studies were carried out by immunohistochemical staining of paraffin-embedded bone marrow samples. Angiogenesis was assessed in the zones of highest vascular density (hot spots), visualized by the expression of endothelial antigen CD34 and expressed as a number of microvessels per high-powerfield (hpf) (final magnification, 400x). Proliferative activity was estimated by the expression of nuclear protein Ki-67, cyclin A and mean number of nucleolar organizer regions (AgNORs). RESULTS: Microvessel density was higher in B-CLL marrow than in normal marrow (30.1 and 16.44 per hpf, respectively) and was higher in the diffuse than nondiffuse pattern (33.6 and 27.5 per hpf, respectively). B-CLL bone marrow also showed higher proliferative activity, as assessed by mean number of AgNORs, than did normal marrow (1.52 and 1.25, respectively) and a higher mean percentage of cyclin A-positive cells (7.5 and 6.8, respectively). In contrast, mean Ki-67 expression was similar in B-CLL and the control group. Mean AgNORs number, Ki-67 and cyclin A-positive cell percentage were significantly higher in B-CLL marrow with a diffuse as compared to nondiffuse involvement pattern (AgNORs, 1.75 and 1.35; cyclin A, 9.27% and 3.95%; Ki-67, 34.9% and 23.3%, respectively). CONCLUSION: Our results indicate enhancement of bone marrow angiogenesis in B-CLL and a relationship between microvessel density and the bone marrow infiltration pattern. The study points also to a possible relationship between the bone marrow infiltration pattern and proliferative activity of bone marrow cells.  相似文献   
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