CNS-oxygen toxicity and blood glucose levels in MnSOD enzyme knockdown mice

Many studies have been conducted in the search for the mechanism underlying CNS-oxygen toxicity (OT), which may be fatal when diving with a closed-circuit apparatus. We investigated the influence of hyperbaric oxygen (HBO) on blood glucose level (BGL) in Mn-superoxide dismutase (SOD2) knockdown mice regarding CNS-OT in particular under stress conditions such as hypoglycemia or hyperglycemia. Two groups of mice were used: SOD2 knockdown (Heterozygous, HET) mice and their WT family littermates. Animals were exposed to HBO from 2 up to 5 atmosphere absolute (ATA). Blood samples were drawn before and after each exposure for measurement of BGL. The mice were sacrificed following the final exposure, which was at 5 ATA. We used RT-PCR and Western blot to measure levels of glucose transporter 1 (GLUT1) and hypoxia inducible factor (HIF)1a in the cortex and hippocampus. In the hypoglycemic condition, the HET mice were more sensitive to oxidative stress than the WT. In addition, following exposure to sub-toxic HBO, which does not induce CNS-OT, BGL were higher in the HET mice compared with the WT. The expression of mRNA of GLUT1 and HIF-1a decreased in the hippocampus in the HET mice, while the protein level decreased in the HET and WT following HBO exposure. The results suggest that the higher BGL following HBO exposure especially at SOD2 HET mice is in part due to reduction in GLUT1 as a consequence of lower HIF-1a expression. This may add part to the puzzle of the understanding the mechanism leading to CNS-OT.

Novel Nanoparticle-Based Cancer Treatment, Effectively Inhibits Lung Metastases and Improves Survival in a Murine Breast Cancer Model

Sarah Nanoparticles (SaNPs) are unique multicore iron oxide-based nanoparticles, developed for the treatment of advanced cancer, following standard care, through the selective delivery of thermal energy to malignant cells upon exposure to an alternating magnetic field. For their therapeutic effect, SaNPs need to accumulate in the tumor. Since the potential accumulation and associated toxicity in normal tissues are an important risk consideration, biodistribution and toxicity were assessed in naïve BALB/c mice. Therapeutic efficacy and the effect on survival were investigated in the 4T1 murine model of metastatic breast cancer. Toxicity evaluation at various timepoints did not reveal any abnormal clinical signs, evidence of alterations in organ function, nor histopathologic adverse target organ toxicity, even after a follow up period of 25 weeks, confirming the safety of SaNP use. The biodistribution evaluation, following SaNP administration, indicated that SaNPs accumulate mainly in the liver and spleen. A comprehensive pharmacokinetics evaluation, demonstrated that the total percentage of SaNPs that accumulated in the blood and vital organs was ~78%, 46%, and 36% after 4, 13, and 25 weeks, respectively, suggesting a time-dependent clearance from the body. Efficacy studies in mice bearing 4T1 metastatic tumors revealed a 49.6% and 70% reduction in the number of lung metastases and their relative size, respectively, in treated vs. control mice, accompanied by a decrease in tumor cell viability in response to treatment. Moreover, SaNP treatment followed by alternating magnetic field exposure significantly improved the survival rate of treated mice compared to the controls. The median survival time was 29 ± 3.8 days in the treated group vs. 21.6 ± 4.9 days in the control, p-value 0.029. These assessments open new avenues for generating SaNPs and alternating magnetic field application as a potential novel therapeutic modality for metastatic cancer patients.

A simplified ingestion procedure for esophageal capsule endoscopy: initial evaluation in healthy volunteers

BACKGROUND AND STUDY AIMS

Initial studies on esophageal capsule endoscopy (PillCam ESO) reported excellent sensitivity and specificity, but these were followed by mixed results in several subsequent studies, probably due to deviations from the recommended ingestion protocol and the inconvenience of capsule ingestion in the supine position. The aim of this study was therefore to test a simplified ingestion procedure (SIP) for PillCam ESO.

PATIENTS AND METHODS

Using a cross-over study design, the SIP was prospectively compared with the original ingestion procedure for PillCam ESO in 24 healthy volunteers (15 men, nine women; mean age 44, range 27 - 70) and evaluated for: bubbles/saliva interference at the Z-line, Z-line circumferential visualization (quadrants), and convenience and ease of the ingestion procedure. All Rapid 4 videos were reviewed in a randomized manner and read by an experienced PillCam ESO reader blinded to the ingestion procedure used.

RESULTS

It was found that the SIP significantly improved visualization in comparison with the original ingestion procedure, with less interference due to bubbles/saliva observed at the gastroesophageal junction ( P = 0.002) and improved visualization of the Z-line ( P = 0.025). Although the esophageal transit time was significantly faster with the SIP (3 : 45 min vs. 0 : 38 min; P = 0.0001), there were no differences in the number of Z-line frames/images captured.

CONCLUSIONS

This new, simplified ingestion procedure for PillCam ESO provides significantly improved visualization of the Z-line in healthy volunteers. The overall test characteristics of PillCam ESO using SIP should be tested in patients with esophageal disease.

Measurement of cardiac function in conscious rats

The goal of this study was to establish that 1. blood velocity profile in the rat aorta is parabolic, and 2. measure of left ventricular thickening fraction can be used in rats. Spontaneously hypertensive and normotensive Wistar Kyoto rats were instrumented with a 20-MHz pulsed Doppler flow probe around the thoracic aorta and a 20-MHz pulsed Doppler thickening probe on the left ventricle. Doppler frequency shifts were measured throughout the entire aorta diameter, and individual blood velocity profiles were constructed. It was demonstrated that blood velocity in the ascending aorta of rats is laminar; therefore, cardiac output can be measured using the pulsed Doppler method. In Wistar Kyoto rats, left ventricular thickening fraction was 24 +/- 1% and 25 +/- 1%, 2 and 3 weeks following surgery. In spontaneously hypertensive rats, left ventricular thickening fraction was 22 +/- 2%. Halothane depressed left ventricular thickening fraction, whereas isoproterenol increased left ventricular thickening fraction in conscious rats. Thus, pulsed Doppler technique is a valuable tool for evaluating cardiovascular function in conscious rats.

Endometrial laser intrauterine thermotherapy: the first series of 100 patients observed for 1 year

OBJECTIVE

To describe a new instrument (GyneLase) that offers a new approach (endometrial laser intrauterine thermal therapy [ELITT]) to treatment of menorrhagia and to evaluate the efficacy of ELITT in the management of dysfunctional uterine bleeding.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

100 premenopausal women with dysfunctional uterine bleeding were observed for 1 year.

INTERVENTION(S)

Intrauterine laser thermotherapy with a diode laser.

MAIN OUTCOME MEASUREMENT(S)

Amenorrhea rate after 1 year.

RESULT(S)

The amenorrhea rate after 1 year of follow-up was 71%, and the rate of amenorrhea/severe hypomenorrhea rate was >90%; these rates are much higher than those in the literature after such procedures as electrosurgery or intrauterine thermal balloon therapy. The ELITT procedure is an inherently safe and simple alternative, providing controlled and effective treatment of the entire endometrium. In contrast to traditional endometrial ablation using a neodymium yttrium-aluminum-garnet laser, the ELITT procedure does not require intensive training or hysteroscopic control; it is also far less risky, because the power used per unit area is 1,000 times lower.

CONCLUSION(S)

The ELITT procedure is a new nonhysteroscopic technique for endometrial ablation. The technique is very safe and offers the highest amenorrhea rate to date in the literature.

Endometrial laser intrauterine thermo-therapy (ELITT): a revolutionary new approach to the elimination of menorrhagia

Various non-hysteroscopic procedures have been developed in the attempt to treat dysfunctional uterine bleeding that fails to respond to medical treatment efficiently and easily. Among these procedures is low-dose laser radiation of the endometrium with the diode source, which is characterized by the highest incidence of amenorrhea.

Parental attitudes toward obstetric ultrasound examination

OBJECTIVE

The aim of the study was to assess the effect of ultrasound examination on parental attitudes and anxieties.

MATERIAL AND METHOD

Ultrasound examinations were carried out on 1,089 pregnant women with uncomplicated pregnancies at a mean gestational age of 20.9 weeks (minimum 10 weeks). Before and after the ultrasound examination, patients completed a questionnaire comprising 26 five-point numerical scales relating to anxiety levels, and difference scores for pre- and post-scan levels of fears and anxieties were computed.

RESULTS

We showed that the reduction of anxiety following ultrasound examination was inversely related to gestational age, but was unrelated to demographic or medical variables, such as the risk level at the time of the scan. Similarly, anxiety was not reduced because of the presence of the spouse, although the spouse's presence did significantly increase inter-partner bonding.

CONCLUSION

This study showed that "routine" ultrasound scan may have significant psychological effects on parental attitudes toward each other and the fetus.

Ultrasonographic "endometrial three-layer" pattern: a unique finding in ectopic pregnancy

Although diagnostic ultrasonography is playing an increasing role in the investigation of the patient with suspected ectopic pregnancy (EP), it has significant limitations in the very early stages of pregnancy. By sonographically exploring the intrauterine echoes in 45 cases of documented EP, we demonstrated a unique pattern in 28 cases (62.2%). A well-defined spheric structure forming an endometrial three-layer (ETL) pattern was seen, probably formed by a midline echo between the two adjacent edematous proliferative layers of the endometrium, the latter resembling the late proliferative endometrium. In 17 patients with a proved EP (37.8%), the ETL pattern was not demonstrated. However, the ETL was not demonstrated in all 40 cases of early intrauterine pregnancy and all 50 cases of miscarriage. These findings suggest a 100% specificity and a sensitivity of 62.2% for the ETL pattern in the diagnosis of EP.

An experimental study of pressure losses in pulsatile flows through rigid and pulsating stenosis

The time-dependent pressure curves of a pulsatile flow across rigid and pulsating stenoses were investigated experimentally in a laboratory simulator of the outflow tract of the heart right ventricle. The experiments were performed within the range of physiological conditions of frequency and flow rate. The experimental setup consisted of a closed flow system which was operated by a pulsatile pump, and a test chamber which enabled checking different modes of stenosis. Rigid constrictions were simulated by means of axisymmetric blunt-ended annular plugs with moderate-to-severe area reductions. The pulsating stenosis consisted of a short starling resistor device operated by a pulsating external pressure which was synchronized by the pulsatile flow. It was found that the shape of the time-dependent pressure curve upstream of the stenosis was different in the case of rigid stenosis than in the pulsating one. Potential clinical applications of the work may relate to diagnosis of the type of stenosis in the congenital heart disease known as Tetralogy of Fallot.