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21.
Juan Carlos Zenteno Marisol López Clementina Vera Juan Pablo Méndez S. Kofman-Alfaro 《Human genetics》1997,100(5-6):606-610
We report a Mexican family in which two sibs were identified as “classic” XX males without genital ambiguities. Molecular
studies revealed that both patients were negative for several Y sequences, including SRY. A review of familial cases disclosed that this is the first family where a complete male phenotype was observed in Y-negative
XX male non-twin brothers. These data suggest that an inherited loss-of-function mutation, in a gene participating in the
sex-determining cascade, can induce normal male sexual differentiation in the absence of SRY.
Received: 5 March 1997 / Accepted: 9 May 1997 相似文献
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Simone Bertini Elisa Ghilardi Valentina Asso Filippo Minutolo Simona Rapposelli Maria Digiacomo Giuseppe Saccomanni Veronica Salmaso Mattia Sturlese Stefano Moro Marco Macchia Clementina Manera 《Bioorganic & medicinal chemistry letters》2017,27(21):4812-4816
A novel series of variously substituted N-[3-(9H-carbazol-9-yl)-2-hydroxypropyl]-arylsulfonamides has been synthesized and assayed for β-Secretase (BACE1) inhibitory activity. BACE1 is a widely recognized drug target for the prevention and treatment of Alzheimer's Disease (AD). The introduction of benzyl substituents on the nitrogen atom of the arylsulfonamide moiety has so far led to the best results, with three derivatives showing IC50 values ranging from 1.6 to 1.9?μM. Therefore, a significant improvement over the previously reported series of N-carboxamides (displaying IC50’s?≥?2.5?μM) has been achieved, thus suggesting an active role of the sulfonamido-portion in the inhibition process. Preliminary molecular modeling studies have been carried out to rationalize the observed structure-activity relationships. 相似文献
24.
Aims The evolution of the outstanding variation of reproductive systems in angiosperms has been considered an important driver of lineage diversification. Closely related hermaphroditic and dioecious species with biotic pollination provide the opportunity to study and compare traits related to pollinator attraction and their consequences on reproductive components. A higher predictability of pollination syndromes is expected in dioecious species, which are dependent on pollinators, than in self-compatible hermaphroditic taxa. Dioecious species may suffer pollen limitation depending on the quality of floral rewards and the kind and abundance of pollinators, whereas no pollen limitation is expected in hermaphroditic species with autonomous self-pollination. Additionally, in the absence of pollen limitation, more or better seeds are expected in dioecious species, according to the sexual specialization hypothesis.Methods In natural populations of the hermaphroditic Fuchsia fulgens and Fuchsia arborescens and dioecious Fuchsia parviflora and Fuchsia obconica, all endemic to Mexico, we first described flower phenology, flower production and longevity and nectar volume and concentration. Then, we evaluated the correspondence between floral visitors and pollination syndromes. In hermaphrodite plants, we determined the level of herkogamy and the potential for autonomous self-pollination. Finally, we evaluated the effect of pollen limitation on fruit set and seed number and assessed seed germination for all species.Important findings In contrast to our prediction, dioecious species did not show a higher correspondence between pollination syndromes and floral visitors than did hermaphrodites; however, male flowers exhibited a higher correspondence than female flowers. No pollen limitation was detected in dioecious species, for which visitation rate did not differ between male and female flowers. The hermaphroditic F. fulgens showed pollen limitation for seed number, despite the presence of autonomous selfing. Fruit set from autonomous pollination was higher in F. arborescens, which showed a lower level of herkogamy compared with F. fulgens. Finally, dioecious species produced fewer but heavier seeds compared with hermaphrodite species. Although Fuchsia is classified as an outcrossing genus, both hermaphroditic species showed autonomous self-pollination. The heavier but lower number of seeds per fruit in dioecious species may be related to the more efficient resource allocation expected from sexual specialization. This could play an important role in the evolution of dioecy; however, a comparative phylogenetic approach is required to confirm this hypothesis. 相似文献
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The effect of various diets on nymphal development and survival of two predaceous anthocorid bugs,Orius albidipennis (Reuter) andO. laevigatus (Fieber) was investigated in the laboratory. Five different diets were compared: eggs ofEphestia kuehniella Zeller; eggs ofE. kuehniella plus mixed flower pollen; only mixed flower pollen; pollen from sweet pepper (Capsicum annuum L. cv. Mazurka) flowers; and sweet pepper plants. A high percentage of predators successfully completed nymphal development on those diets containing lepidopterous eggs. When fed on sweet pepper pollen, the survival percentages were 65% forO. laevigatus and 38% forO. albidipennis. No nymphs of either species completed the nymphal stage on mixed flower pollen or on sweet pepper plants. Development was significantly faster on diets containing eggs ofE. kuehniella. Results are discussed in relation to the capability of the bugs to survive periods of prey scarcity and to the optimization of release strategies for these predators in the greenhouse. 相似文献
27.
Angelo S. Nyamtema Nguke Mwakatundu Sunday Dominico Hamed Mohamed Senga Pemba Richard Rumanyika Clementina Kairuki Irene Kassiga Allan Shayo Omary Issa Calist Nzabuhakwa Chagi Lyimo Jos van Roosmalen 《PloS one》2016,11(3)
Background
In Tanzania, maternal mortality ratio (MMR), unmet need for emergency obstetric care and health inequities across the country are in a critical state, particularly in rural areas. This study was established to determine the feasibility and impact of decentralizing comprehensive emergency obstetric and neonatal care (CEmONC) services in underserved rural areas using associate clinicians.Methods
Ten health centres (HCs) were upgraded by constructing and equipping maternity blocks, operating rooms, laboratories, staff houses and installing solar panels, standby generators and water supply systems. Twenty-three assistant medical officers (advanced level associate clinicians), and forty-four nurse-midwives and clinical officers (associate clinicians) were trained in CEmONC and anaesthesia respectively. CEmONC services were launched between 2009 and 2012. Monthly supportive supervision and clinical audits of adverse pregnancy outcomes were introduced in 2011 in these HCs and their respective district hospitals.Findings
After launching CEmONC services from 2009 to 2014 institutional deliveries increased in all upgraded rural HCs. Mean numbers of monthly deliveries increased by 151% and obstetric referrals decreased from 9% to 3% (p = 0.03) in HCs. A total of 43,846 deliveries and 2,890 caesarean sections (CS) were performed in these HCs making the mean proportion of all births in EmONC facilities of 128% and mean population-based CS rate of 9%. There were 190 maternal deaths and 1,198 intrapartum and very early neonatal deaths (IVEND) in all health facilities. Generally, health centres had statistically significantly lower maternal mortality ratios and IVEND rates than district hospitals (p < 0.00 and < 0.02 respectively). Of all deaths (maternal and IVEND) 84% to 96% were considered avoidable.Conclusions
These findings strongly indicate that remotely located health centres in resource limited settings hold a great potential to increase accessibility to CEmONC services and to improve maternal and perinatal health. 相似文献28.
Edith Falcón-Ramírez Leonora Casas-Avila Antonio Miranda Pilar Diez Clementina Castro Julieta Rubio Rocío Gómez Margarita Valdés-Flores 《Molecular biology reports》2011,38(5):2987-2992
The Sp1 binding site polymorphism in collagen type I alpha 1 gene (COLIA1) has been associated with osteoporosis (OP) and
bone mineral density (BMD). The aim of this study was to explore the association of this polymorphism with OP and BMD in the
Mexican population by polymerase chain reaction and restriction fragment length polymorphism (PCR–RFLP) procedure. Allelic
and genotypic frequencies from the Sp1 polymorphism were determined in 100 women with OP, 100 women without OP and 500 subjects
from general Mexican population (GMP). Distribution of Sp1 polymorphism was in Hardy–Weinberg equilibrium. In spite of population
structure due to racial mix in Mexican population, associations with OP were demonstrated. The frequency of “s” allele was
significantly higher in women with OP (35%) than in women without OP (11%; P < 0.00001). Interestingly, “ss” genotype, was exclusive of women with OP and was associated with low BMD (0.588 ± 0.077 g/cm2) in contrast to “SS” genotype (0.733 ± 0.039 g/cm2; P = 0.0001). This work confirms the association of Sp1 polymorphism with low BMD and OP in Mexican population and make sure
to use Sp1 as a genetic marker for OP in our population. 相似文献
29.
OS Isikhuemhen NA Mikiashvili CO Adenipekun EI Ohimain G Shahbazi 《World journal of microbiology & biotechnology》2012,28(5):1961-1966
Lentinus squarrosulus Mont., a high temperature tolerant white rot fungus that is found across sub-Saharan Africa and many parts of Asia, is attracting
attention due to its rapid mycelia growth and potential for use in food and biodegradation. A solid state fermentation (SSF)
experiment with L. squarrosulus (strain MBFBL 201) on cornstalks was conducted. The study evaluated lignocellulolytic enzymes activity, loss of organic matter
(LOM), exopolysaccharide content, and the release of water soluble sugars from degraded substrate. The results showed that
L. squarrosulus was able to degrade cornstalks significantly, with 58.8% LOM after 30 days of SSF. Maximum lignocellulolytic enzyme activities
were obtained on day 6 of cultivation: laccase = 154.5 U/L, MnP = 13 U/L, peroxidase = 27.4 U/L, CMCase = 6.0 U/mL and xylanase = 14.5 U/mL.
L. squarrosulus is a good producer of exopolysaccharides (3.0–5.13 mg/mL). Glucose and galactose were the most abundant sugars detected in
the substrate during SSF, while fructose, xylose and trehalose, although detected on day zero of the experiment, were absent
in treated substrates. The preference for hemicellulose over cellulose, combined with the high temperature tolerance and the
very fast growth rate characteristics of L. squarrosulus could make it an ideal candidate for application in industrial pretreatment and biodelignification of lignocellulosic biomass. 相似文献
30.
doi: 10.1111/j.1741‐2358.2011.00542.x Association between oral health, cognitive impairment and oral health–related quality of life Objective: Investigating oral health–related quality of life’s (OH‐QoL) relationship with cognitive state. Background: Oral health affects OH‐QoL and is poor in institutionalised and cognitively impaired people. Material and Methods: This was a cross‐sectional study involving 215 institutionalised elderly (82.9 mean age), who were interviewed, examined and cognitively screened using the Pfeiffer test. Results: Mean GOHAI score was 53.1; only 43.7% of the participants reported having a good OH‐QoL. Needing help with dressing or washing (OR 2.14; p = 0.004), having one to nine teeth (OR 4.65; p ≥ 0.001), eight or less occluding pairs (OR 2.74; p = 0.002), one to three caries (OR 1.85; p = 0.005) and being cognitive impaired (OR 0.54; p = 0.034) were significantly associated with altered OH‐QoL in bi‐variate analysis. Being edentulous (OR 3.18; p = 0.0046), having 1–9 teeth (OR 2.62; p = 0.056) and presenting mild cognitive impairment (MCI) (OR 0.32; p = 0.016) appeared as predictive variables in logistic regression for having an altered OH‐QoL. Conclusions: Participants having MCI had significantly better GOHAI score than cognitively normal residents. Performing cognitive screening parallel to applying any OH‐QoL instrument would make the results more reliable and would benefit cognitively impaired people. 相似文献