Reproductive hormone patterns in the female guinea-pig serum during the estrous cycle

A study on hormone levels in daily consecutive serum samples during the guinea-pig estrous cycle was performed. Radioimmunoassay (RIA) of immunoreactive LH, FSH and prolactin (IR—LH IR-FSH and lR-prolaetin) developed for determination of rat pituitary hormone was used as well as RIA systems for estradiol-17β and progesterone. In oophorectomized animals estradiol, progesterone and IR-prolactin were undetectable while mean IR- LH and IR-FSH levels were 1.23 ug/l and 1.47 ug/l respectively as expressed in terms of rat hormone references. Prolactin could not be detected in serum during the reproductive cycle. During estrous cycles progesterone showed a biphasic pattern with undetectable levels (< 0.6 nmol/l) around ovulation. Increased levels were observed at the time of implantation. Estradiol-17β concentrations at non-surge time ranged between 0 and 116 pmol/l and a preovulatory peak (mean peak value 142.2 pmol) was noted. Serum IR-LH levels were between 0.2 and 0.8 pg/l and a prcovulatory peak was noted. Furthermore, a preovulatory lR—FSH peak was found (mean peak value 72.7 pg/l). The results indicate a close resemblance to the human reproductive cycle and the guinea-pig is suggested to be the laboratory animal ofchoice for studies on reproduction

15-keto-13, 14-dihydroprostaglandin F2α and prolactin in maternal and cord blood during prostaglandin E2 or oxytocin therapy for labor induction

Peer Reviewe

Long-term exposure to transportation noise and risk of incident stroke:A pooled study of nine scandinavian cohorts

BACKGROUND: Transportation noise is increasingly acknowledged as a cardiovascular risk factor, but the evidence base for an association with stroke is sparse. OBJECTIVE: We aimed to investigate the association between transportation noise and stroke incidence in a large Scandinavian population. METHODS: We harmonized and pooled data from nine Scandinavian cohorts (seven Swedish, two Danish), totaling 135,951 participants. We identified residential address history and estimated road, railway, and aircraft noise for all addresses. Information on stroke incidence was acquired through link-age to national patient and mortality registries. We analyzed data using Cox proportional hazards models, including socioeconomic and lifestyle con-founders, and air pollution. RESULTS: During follow-up (median = 19:5 y), 11,056 stroke cases were identified. Road traffic noise (Lden ) was associated with risk of stroke, with a hazard ratio (HR) of 1.06 [95% confidence interval (CI): 1.03, 1.08] per 10-dB higher 5-y mean time-weighted exposure in analyses adjusted for indi-vidual-and area-level socioeconomic covariates. The association was approximately linear and persisted after adjustment for air pollution [particulate matter (PM) with an aerodynamic diameter of ≤2:5 lm (PM2:5 ) and NO2 ]. Stroke was associated with moderate levels of 5-y aircraft noise exposure (40–50 vs. ≤40 dB) (HR = 1:12; 95% CI: 0.99, 1.27), but not with higher exposure (≥50 dB, HR = 0:94; 95% CI: 0.79, 1.11). Railway noise was not associated with stroke. DISCUSSION: In this pooled study, road traffic noise was associated with a higher risk of stroke. This finding supports road traffic noise as an important cardiovascular risk factor that should be included when estimating the burden of disease due to traffic noise. https://doi.org/10.1289/EHP8949

Imitation of β-lactam binding enables broad-spectrum metallo-β-lactamase inhibitors

Carbapenems are vital antibiotics, but their efficacy is increasingly compromised by metallo-beta-lactamases (MBLs). Here we report the discovery and optimization of potent broad-spectrum MBL inhibitors. A high-throughput screen for NDM-1 inhibitors identified indole-2-carboxylates (InCs) as potential beta-lactamase stable beta-lactam mimics. Subsequent structure-activity relationship studies revealed InCs as a new class of potent MBL inhibitor, active against all MBL classes of major clinical relevance. Crystallographic studies revealed a binding mode of the InCs to MBLs that, in some regards, mimics that predicted for intact carbapenems, including with respect to maintenance of the Zn(II)-bound hydroxyl, and in other regards mimics binding observed in MBL-carbapenem product complexes. InCs restore carbapenem activity against multiple drug-resistant Gram-negative bacteria and have a low frequency of resistance. InCs also have a good in vivo safety profile, and when combined with meropenem show a strong in vivo efficacy in peritonitis and thigh mouse infection models.Peer reviewe

Stereophonic Acoustic Echo Cancellation: Theory and Implementation

The thesis treats theory and implementation aspects for stereophonic acoustic echo cancellation. In Paper I a complete implementation of a stereophonic acoustic echo canceler based on the two-channel fast recursive least-squares algorithm is presented. An analysis of the system calculation complexity is also given, in addition to simulation results on recorded real-life data. Paper II presents a comparison between adaptive filters for usage in stereophonic acoustic echo cancellation. The comparison includes, in addition to the standard normalized least mean square algorithm, the two-channel fast recursive least-squares algorithm and a two-channel frequency-domain adaptive algorithm. In the paper, the convergence rate, the calculation complexity, the signal transmission delay, and the memory usage for the evaluated systems are shown. Adaptive filters applied in subband structures may need to model a few non-causal taps even if the fullband impulse response is causal. This phenomenon is analyzed in Paper III. Formulas to calculate the number of non-causal taps needed are also presented in the paper. The fundamental problem in stereophonic acoustic echo cancellation is the signal correlation between the two channels. In Paper IV it is shown how a perceptual audio coder may decrease this correlation and thereby increase the performance of the stereophonic acoustic echo canceler. Paper V investigates the possibilities of using joint subband filterbanks or time to frequency-domain transforms for echo cancellation and perceptual audio coding. The usage of joint filterbanks/transforms not only decreases the computational complexity of the system, it also reduces the total signal transmission delay of the system if properly designed