Transfer of hydrophilic molecules by placenta and yolk sac of the guinea pig.

Prenatal transfer of hydrophilic materials was studied in chronic guinea pig preparations of ca. 30-65 days gestation. In most preparations the vitelline (yolk sac placenta) circulation of one of the fetuses was ligated between 1 and 20 days before the experiment. Fetal and maternal serum protein concentrations were recorded as a function of the number of days after ligation. Prenatal transfer of hydrophilic materials of 60-5,500 daltons molecular wt was consistent with diffusion, with some evidence of steric restriction of the larger molecules. There was no difference between operated and sham-operated or control fetuses. However, the transfer of radiolabeled homologous gamma globulin ceased after ligation of the yolk sac vessels. The transfer in control fetuses accounted for most of the prenatal requirements of this protein, as calculated from the increases in fetal weight and serum gamma globulin concentrations as a function of gestational age. There was evidence of a nonspecific suppression of yolk sac function by surgery but no evidence of fetal catabolism of gamma globulin.     

Placental insufficiency decreases cell cycle activity and terminal maturation in fetal sheep cardiomyocytes

Umbilicoplacental embolization (UPE) in sheep has been used to investigate the effects of placental insufficiency on fetal development. However, its specific effects on the heart have been little studied. The aim of this study was to determine the effects of placental insufficiency, induced by UPE, on cardiomyocyte size, maturation and proliferation. Instrumented fetal sheep underwent UPE for either 10 or 20 days. Hearts were collected at 125 ± 1 days (10 day group) or 136 ± 1 days (20 day group) of gestation (term ∼145 days). Cell size, maturational state (as measured by the proportion of binucleated myocytes) and cell cycle activity (as measured by positive staining of cells for Ki-67) were determined in dissociated cardiomyocytes. UPE fetuses were hypoxaemic, but mean arterial pressures were not different from controls. UPE fetuses were lighter than control fetuses (10 days: −21%, P < 0.05; 20 days: −27%, P < 0.01) and had smaller hearts, but heart weight was appropriate for body weight. Neither lengths nor widths were different between control and UPE cardiomyocytes at either age. Ten days of UPE did not significantly alter the proportion of binucleated myocytes or cell cycle activity in either ventricle. However, 20 days of UPE reduced cell cycle activity in both ventricles by ∼70% ( P < 0.05); the proportion of binucleated myocytes was also lower in UPE fetuses at this age (left ventricle: 31.1 ± 12.0 versus 46.0 ± 6.6%, P < 0.05; right ventricle: 29.4 ± 12.3 versus 46.3 ± 5.3%, P < 0.05). It is concluded that in the absence of fetal arterial hypertension, placental insufficiency is associated with substantially depressed growth of the heart through suppressed proliferation and maturation of cardiomyocytes.     

Differential actions of dopamine agonists and antagonists on the γ-butyrolactone-induced increase in mouse brain dopamine

-Butyrolactone (GBL) increased the dopamine concentration in the forebrain of the mouse. Apomorphine dose-dependently antagonized the GBL effect, while piribedil was less effective. Haloperidol prevented the antagonism of GBL by apomorphine but pimozide was ineffective in blocking apomorphine. After chronic treatment with haloperidol or pimozide, there was no alteration of the maximum GBL-induced increase in dopamine nor was there any significant change in the antagonism by apomorphine, although a trend toward increased sensitivity to apomorphine was noted in the group withdrawn from haloperidol. These results suggest that in the mouse, haloperidol is a more effective antagonist of presynaptic dopamine autoreceptors than pimozide, while apomorphine is a better presynaptic agonist than piribedil.     

Fetal Electrocardiogram Extraction and Analysis Using Adaptive Noise Cancellation and Wavelet Transformation Techniques

Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed.     

Mild pressure loading alters right ventricular function in fetal sheep

Right ventricular function before and during 10 days of mild pressure loading (10 mm Hg increase in mean pulmonary arterial pressure) was compared with right ventricular function in unloaded near-term fetal sheep. Pressure loading did not alter fetal arterial blood gases or vascular pressures. The right ventricular function curve (stroke volume versus mean right atrial pressure) was not significantly altered by loading. However, the relation between right ventricular stroke volume and increased arterial pressure was dramatically shifted upward, indicating improved ventricular function after the 10-day loading period. Normalized free wall of the loaded right ventricles became thicker (1.2 +/- 0.2 versus 0.9 +/- 0.2 mm/kg, p less than 0.01) and heavier (2.7 +/- 0.4 g/kg versus 2.2 +/- 0.4 g/kg, p less than 0.05) than control, and the ratio of the equatorial radius of curvature to wall thickness decreased (3.2 +/- 0.5 versus 4.5 +/- 0.9, p less than 0.005). Left ventricular free wall and septal weights and thicknesses were not significantly changed. The in vitro diastolic pressure-volume curves of both ventricular chambers of loaded hearts shifted to the left, indicating smaller ventricles than controls at physiological filling pressures. These data suggest the transduction of right ventricular loading effects to the left ventricle. Improved right ventricular function after loading is predicted by the law of Laplace based on the decreased radius of curvature-to-wall thickness ratio.     

Same-day <Superscript>90</Superscript>Y radioembolization: implementing a new treatment paradigm

Purpose

To assess the feasibility of conducting pretreatment mesenteric angiography, coil embolization, ^99mTc macroaggregated albumin (^99mTc-MAA) scintigraphy, and ⁹⁰Y radioembolization treatment in a single, same-day, combined outpatient encounter.

Methods

This was a retrospective study of 78 patients treated during the period 2008 – 2015 who were managed in a single outpatient encounter under the guidance of the Interventional Radiology Department and The Nuclear Medicine Department. Pretreatment planning was performed by reviewing baseline imaging and estimated perfused liver volume bearing the tumor. The region of interest was estimated using 3-D software; this value was used for dosimetry planning. Maximum lung shunting fractions of 10 % for hepatocellular carcinoma and 5 % for liver metastases were assumed. Subsequently, hepatic angiography and ^99mTc-MAA scintigraphy were performed followed by ⁹⁰Y treatment in one outpatient encounter. Total in-room procedure time was recorded.

Results

All patients underwent same-day angiography, ^99mTc-MAA scintigraphy and ⁹⁰Y radioembolization. Of the 78 patients, 16 received multiple segmental treatments to both lobes, 44 received treatment to the right lobe, and 18 received treatment to the left lobe. The median dose was 106 Gy. The median number of ⁹⁰Y vials needed was two (range one to six). The median in-room time was 160 min (75 – 250 min). The residential status of the patients was as follows, 18 % (14/78) were local residents, 55 % (43/78) traveled from outside the city limits, 18 % (14/78) were from out-of-state, and 9 % (7/78) were resident abroad. Of the 78 patients, 61 (77 %) had hepatocellular carcinoma, and 17 (22 %) had liver metastases. The median lung dose was 3.5 Gy.

Conclusion

This study demonstrated the feasibility of same-day ⁹⁰Y evaluation and treatment while maintaining the principles of safe and effective ⁹⁰Y infusion including tumoricidal dosimetry (lobar, segmentectomy), minimization of nontarget flow, and minimization of lung dose. This paradigm translates into expeditious cancer care and significant cost savings.

     

Acute severe asthma

Acute exacerbations of asthma are very common reasons for a presentation to emergency departments. This paper focuses on defining the high‐risk group, consideration of the concept of phenotypes of acute asthma, the assessment of severe and life‐threatening exacerbations and an emphasis on the management of the more severe end of the exacerbation severity. A number of evidence‐based guidelines exist throughout the world and are all slightly different. This reflects the poor evidence base for some of those recommendations. Thus, a large variation of treatment drugs, doses and regimen are used and clearly not standardised. This paper aims to present a summary of the best evidence and discuss some of these controversies. The most important aspect of treating an exacerbation of acute asthma is to review regularly and assess response to treatment. Severe and life‐threatening episodes should be treated with early use of intravenous treatment in a stepwise manner following the local guidelines. Non‐invasive ventilation and high flow nasal cannulae delivery of oxygen in the emergency department are evolving modalities, but evidence for their use is currently limited.