1,481 research outputs found
Efficacy of Cervical Mucus Observations Plus Electronic Hormonal Fertility Monitoring as a Method of Natural Family Planning
Objective: To determine the effectiveness of an electronic hormonal fertility monitor plus cervical mucus monitoring to avoid pregnancy. Design: A 12-month prospective clinical efficacy trial. Setting and Participants: One hundred ninety five (195) women (mean age 29.8 years) seeking to avoid pregnancy with a natural method at 5 clinical sites in 4 cities. Intervention: Each participant was taught to track fertility by self-observation of cervical mucus and an electronic monitor that measures urinary levels of estrone-3-glucuronide and luteinizing hormone. Main Outcome Measures: Correct-and typical-use unintended pregnancy rates. Results: There were a total of 26 unintended pregnancies, 3 with correct use. With 1,795 months of use, the correct-use pregnancy rate was 2.1% per 12 months of use (i.e., 97.9% effective in avoiding pregnancy when rules of the method were always followed) and the imperfect-use pregnancy rate was 14.2% per 12 months of use (i.e., 85.8% effective in avoiding pregnancy when rules of the method were not always followed and all unintended pregnancies and months of use were included in the calculations). Conclusions: Correct use of an electronic hormonal fertility monitor with cervical mucus observations can be as effective as other fertility awarenessâbased methods of natural family planning. Comparative studies are needed to confirm this conclusion
Timing of Moderate Level Prenatal Alcohol Exposure Influences Gene Expression of Sensory Processing Behavior in Rhesus Monkeys
Sensory processing disorder, characterized by over- or under-responsivity to non-noxious environmental stimuli, is a common but poorly understood disorder. We examined the role of prenatal alcohol exposure, serotonin transporter gene polymorphic region variation (rh5-HTTLPR), and striatal dopamine (DA) function on behavioral measures of sensory responsivity to repeated non-noxious sensory stimuli in macaque monkeys. Results indicated that early gestation alcohol exposure induced behavioral under-responsivity to environmental stimuli in monkeys carrying the short (s) rh5-HTTLPR allele compared to both early-exposed monkeys homozygous for the long (l) allele and monkeys from middle-to-late exposed pregnancies and controls, regardless of genotype. Moreover, prenatal timing of alcohol exposure altered the relationship between sensory scores and DA D2R availability. In early-exposed monkeys, a positive relationship was shown between sensory scores and DA D2R availability, with low or blunted DA function associated with under-responsive sensory function. The opposite pattern was found for the middle-to-late gestation alcohol-exposed group. These findings raise questions about how the timing of prenatal perturbation and genotype contributes to effects on neural processing and possibly alters neural connections
Characteristics of the Menstrual Cycle After Discontinuation of Oral Contraceptives
Background: Menstrual cycle function may continue to be altered after discontinuation of oral contraceptives (OC). Few studies have been published on the effects of recent OC use on menstrual cycle parameters; none have examined characteristics of the menstrual flow or the quality of cervical mucus. The purpose of this retrospective matched cohort study is to assess biomarkers of the menstrual cycle after discontinuation of OCs.
Methods: Among a sample of women who daily recorded observations of menstrual cycle biomarkers, 70 women who had recently discontinued OCs were randomly matched by age and parity with 70 women who had not used OCs for at least 1 year. Outcomes investigated included overall cycle length, length of the luteal phase, estimated day of ovulation, duration of menstrual flow, menstrual intensity, and mucus score. Differences between recent OC users and controls were assessed using random effects modeling.
Results: Recent OC users had statistically significantly lower scores for mucus quality for cycles 1 and 2. Additionally, OC users had a later estimated day of ovulation that was statistically significant in cycle 2 and a decreased intensity of menstrual flow that was significant in the first four cycles (difference = â0.48 days). In random effects modeling, all these parameters were significantly different for the first six cycles combined.
Conclusions: Menstrual cycle biomarkers are altered for at least two cycles after discontinuation of OCs, and this may help explain the temporary decrease in fecundity associated with recent OC use
Temperature-dependent characteristics and single-mode performance of AlGaInP-based 670-690-nm vertical-cavity surface-emitting lasers
Includes bibliographical references.We report on temperature dependent characteristics and single mode performance of one-wave cavity, planar implanted, AlGaInP-based vertical-cavity surface emitting lasers. By optimizing the overlap between the gain peak and the cavity mode of the structure, we demonstrate record device performance, including 8.2 mW maximum output power and 11% power conversion efficiency for multimode operation and 1.9 mW and 9.6% power conversion efficiency for single mode operation at 687 nm. Improved performance at elevated temperatures is also achieved, with 1.5 mW output power demonstrated at 50 °C from a 15-Όm-diameter device.This letter was supported by the US Department of Energy under contract no. DE-AC04-94AL85000
Differential Effects of the Mitochondria-Active Tetrapeptide SS-31 (D-Arg-dimethylTyr-Lys-Phe-NH<sub>2</sub>) and Its Peptidase-Targeted Prodrugs in Experimental Acute Kidney Injury.
The mitochondria-active tetrapeptide SS-31 can control oxidative tissue damage in kidney diseases. To investigate other potential beneficial nephroprotective effects of SS-31, in vivo murine models of acute tubular injury and glomerular damage were developed. Reduction of acute kidney injury was demonstrated in mice treated with SS-31. The expression of mRNAs involved in acute inflammatory and oxidative stress responses in the diseased kidneys confirmed that SS-31 could regulate these pathways in our in vivo models. Furthermore, ex vivo histoenzymography of mouse kidneys showed that aminopeptidase A (APA), the enzyme involved in the processing of angiotensin (Ang) II to Ang III, was induced in the diseased kidneys, and its activity was inhibited by SS-31. As the renin-angiotensin system (RAS) is a main regulator of kidney functions, the modulation of Ang receptors (ATR) and APA by SS-31 was further investigated using mRNAs extracted from diseased kidneys. Following acute tubular and/or glomerular damage, the expression of the AT <sub>1</sub> R mRNA was upregulated, which could be selectively downregulated upon SS-31 administration to the animals. At the same time, SS-31 was able to increase the expression of the AT <sub>2</sub> R, which may contribute to limit renal damage. Consequently, SS-31-based prodrugs were developed as substrates and/or inhibitors for APA and were screened using cells expressing high levels of APA, showing its selective regulation by α-Glu-SS-31. Thus, a link between SS-31 and the RAS opens new therapeutic implications for SS-31 in kidney diseases
Autophagy and Schizophrenia: A Closer Look at How Dysregulation of Neuronal Cell Homeostasis Influences the Pathogenesis of Schizophrenia
Autophagy, the process of degrading intracellular components in lysosomes, plays an important role in the central nervous system by contributing to neuronal homeostasis. Autophagic failure has been linked to neurologic dysfunction and a variety of neurodegenerative diseases. Recent investigation has revealed a novel role for autophagy in the context of mental illness, namely in schizophrenia. This article summarizes the phenomenology, genetics, and structural/histopathological brain abnormalities associated with schizophrenia. We review studies that demonstrate for the first time a connection between autophagy malfunction and schizophrenia. Transcriptional profiling in schizophrenia patients uncovered a dysregulation of autophagy-related genes spatially confined to a specific area of the cortex, Brodmann Area 22, which has been previously implicated in the positive symptoms of schizophrenia. We also discuss the role of autophagy activators in schizophrenia and whether they may be useful adjuvants to the traditional antipsychotic medications currently used as the standard of care. In summary, the field has progressed beyond the basic concept that autophagy impairment predisposes to neurodegeneration, to a mechanistic understanding that loss of autophagy can disrupt neuronal cell biology and predispose to mood disorders, psychotic symptoms, and behavioral change.
Pregnancy Induces Persistent Changes that Potentiate Apoptotic Signaling and Responses to DNA Damage
A full-term pregnancy reduces the lifetime risk of breast cancer by up to 50%. This effect is mediated, in part, by p53-dependent pathways. Gene expression profiling was used to investigate the mechanisms that alter apoptotic responses to DNA damage in the mammary gland. Radiation-induced responses in BALB/c-Trp53+/+ and BALB/c-Trp53-/- mice identified 121 genes that were altered by radiation and p53 status (p53-IR). To determine the effect of parity, mice were mated, force-weaned and mammary glands were allowed to involute for 21 days (parous) and compared with age-matched nulliparous mice. Gene expression profiles were determined in mammary tissues from nulliparous (N), parous (P), irradiated nulliparous (N-IR) and irradiated parous (P-IR) mice. The p53-IR gene signature did not differ among the N-IR and P-IR groups indicating that transcriptional activity of p53 was not altered by parity. However, expression profiles of apoptosis-related genes differed significantly in the parous group. The alterations in parous mammary tissues was accompanied by over-representation of biological processes that included âsignal transductionâ (e=1.69E-05). Within this set, Wnt signaling was especially pronounced (e
Parity-regulated genes collaborate with p53-dependent targets, which act as a âswitchâ, to elicit apoptosis following ionizing radiation. The epigenetic states of the parity-regulated genes Tgfb2 and Wnt5a provide a mechanism for the persistent alterations in gene expression and apoptosis in parous mammary epithelial cells
Improved AlGaInP-based red (670â690 nm) surface-emitting lasers with novel C-doped short-cavity epitaxial design
Includes bibliographical references (page 331).A modified epitaxial design leads to straightforward implementation of short (1λ) optical cavities and the use of C as the sole p-type dopant in AlGaInP/AlGaAs red vertical-cavity surface-emitting lasers (VCSELs). Red VCSELs fabricated into simple etched air posts operate continuous wave at room temperature at wavelengths between 670 and 690 nm, with a peak output power as high as 2.4 mW at 690 nm, threshold voltage of 2.2 V, and peak wallplug efficiency of 9%. These values are all significant improvements over previous results achieved in the same geometry with an extended optical cavity epitaxial design. The improved performance is due primarily to reduced optical losses and improved current constriction and dopant stability.This work was supported by the U.S. Department of Energy under Contract No. DE-AC04-94AL85000
Machine learning reveals singing rhythms of male Pacific field crickets are clock controlled
Circadian rhythms are ubiquitous in nature and endogenous circadian clocks drive the daily expression of many fitness-related behaviors. However, little is known about whether such traits are targets of selection imposed by natural enemies. In Hawaiian populations of the nocturnally active Pacific field cricket (Teleogryllus oceanicus), males sing to attract mates, yet sexually selected singing rhythms are also subject to natural selection from the acoustically orienting and deadly parasitoid fly, Ormia ochracea. Here, we use T. oceanicus to test whether singing rhythms are endogenous and scheduled by circadian clocks, making them possible targets of se lection imposed by flies. We also develop a novel audio-to-circadian analysis pipeline, capable of extracting useful parameters from which to train machine learning algorithms and process large quantities of audio data. Singing rhythms fulfilled all criteria for endogenous circadian clock control, including being driven by photoschedule, self-sustained periodicity of approximately 24 h, and being robust to variation in temperature. Furthermore, singing rhythms varied across individuals, which might suggest genetic variation on which natural and sexual selection pressures can act. Sexual signals and ornaments are well-known targets of selection by natural enemies, but our findings indicate that the circadian timing of those traitsâ expression may also determine fitnes
Impact de l'introduction des légumineuses dans les systÚmes de culture sur les émissions de protoxyde d'azote
Dans un objectif d'attĂ©nuation du rĂ©chauffement climatique, la mise en place de systĂšmes de culture plus autonomes vis - Ă - vis des engrais minĂ©raux devient incontournable pour rĂ©duire les Ă©missions de gaz Ă effet de serre (GES) tout en diminuant le coĂ»t de la fertilisation. L'insertion de lĂ©gumineuses dans ces systĂšmes semble ĂȘtre un levier prometteur pour y parvenir. Les Ă©conomies d'azote permises par diffĂ©rents modes d'introduction de lĂ©gumineuses et leur impact sur les Ă©missions de GES ont Ă©tĂ© estimĂ©s et Ă©valuĂ©s en quantifiant au prĂ©alable les flux d'azote dans les systĂšmes avec ou sans lĂ©gumineuses Ă partir de donnĂ©es issues de dispositifs expĂ©rimentaux prĂ©existants, disponibles dans la bibliographie ou acquises dans de nouveaux essais. L'introduction de lĂ©gumineuses prĂ©sente rĂ©guliĂšrement un impact positif sur la rĂ©duction de l'emploi des engrais azotĂ©s. Le risque d'augmentation de la lixiviation du nitrate dĂ©pend de leur mode d'introduction et de leur place dans les rotations. Enfin, les Ă©missions mesurĂ©es en cul tures principales de lĂ©gumineuses sont gĂ©nĂ©ralement trĂšs significativement rĂ©duites en comparaison des cultures fertilisĂ©es, cependant la dĂ©gradation des rĂ©sidus des lĂ©gumineuses (en culture ou en couverts) peut gĂ©nĂ©rer des Ă©missions de N 2 O corrĂ©lĂ©es Ă leur impact sur les flux d'azote, variable selon les conditions pĂ©doclimatiques. Ces rĂ©sultats devraient permettre d'Ă©laborer des recommandations pour mieux prendre en compte les lĂ©gumineuses dans la conception de systĂšmes de culture plus autonomes vis - Ă - vis des engrais azotĂ©s de synthĂšse et moins Ă©metteurs de N 2 0
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