Resuscitative Endovascular Balloon Occlusion of the Aorta Using a Low-Profile Device is Easy and Safe for Emergency Physicians in Cases of Life-Threatening Hemorrhage

Background

Bleeding from hemorrhagic shock can be immediately controlled by blocking the proximal part of the hemorrhagic point using either resuscitative thoracotomy for aortic cross-clamping or insertion of a large-caliber (10–14Fr) resuscitative endovascular balloon occlusion of the aorta (REBOA) device via the femoral artery. However, such methods are very invasive and have various complications. With recent progress in endovascular treatment, a low-profile REBOA device (7Fr) has been developed.

Subretinal injection of recombinant tissue plasminogen activator for submacular hemorrhage associated with ruptured retinal arterial macroaneurysm

Purpose

To evaluate the surgical outcomes of small-gauge vitrectomy with subretinal injection of recombinant tissue plasminogen activator (rt-PA) for a submacular hemorrhage caused by a ruptured retinal arterial macroaneurysm (RAM).

Methods

Non-comparative, consecutive case-series performed at two ophthalmological institutions. We examined 22 eyes of 22 patients with a submacular hemorrhage associated with a RAM but without a preretinal or sub-internal limiting membrane hemorrhage at the fovea. During 25-gauge vitrectomy, approximately 4000–8000 IU of rt-PA was injected subretinally, followed by the injection of air or 10 % sulfur hexafluoride as a tamponade. The patients maintained an upright position for 1 hour, then turned to a facedown position for 1 to 3 days. The best-corrected visual acuity (BCVA) and postoperative complications were evaluated.

Results

The average interval from the onset of symptoms to surgery was 8.4?±?7.6 days, and the average size of the subretinal hemorrhage was 3.4?±?1.0 disc diameters. The submacular hemorrhage was displaced from the foveal area in all eyes after 1 week. The mean baseline BCVA was 1.41?±?0.41 logMAR units, and it improved to 0.91?±?0.43 at 1 month and to 0.64?±?0.45 at the final visit (P?=?0.0001, P?<?0.0001 respectively). A macular hole was detected intraoperatively in two eyes and postoperatively in two eyes, and both were closed by internal limiting membrane peeling or a second vitrectomy.

Conclusions

Small-gauge vitrectomy with subretinal rt-PA injection and gas tamponade were effective in displacing a submacular hemorrhage associated with a RAM.

     

Effect of various organic anions on the plasma disappearance of 1-anilino-8-naphthalene sulfonate

The effects of various organic anions on the hepatic transport of an anionic fluorescent dye, 1-anilino-8-naphthalene sulfonate (ANS) were investigated by measuring the plasma disappearance-time profiles in rats. Ten min after the i.v. administration of ANS (3 mumol/kg), various organic anions (60 mumol/kg) were injected in a bolus. Sulfobromophthalein (BSP), bromophenol blue (BPB) and rose bengal (RB) induced a transient increase in the plasma concentration of ANS (the so-called 'counter-transport' phenomena). The effect of rose bengal was somewhat different. After the administration of rose bengal, the plasma concentration of ANS decreased rapidly followed by a gradual increase. On the other hand, after the administration of bilirubin and taurocholate, the transient increases in plasma ANS concentrations were minimal. No effect was observed after the administration of phenolsulfophthalein (PSP) or oleate. The effects of these organic anions on the binding of ANS to rat liver cytosols were examined by equilibrium dialysis. Sulfobromophthalein, bromophenol blue and rose bengal, which yielded an in vivo 'counter-transport' phenomena, markedly inhibited ANS binding to cytosolic proteins. On the other hand, the other organic anions examined had very small, if any, inhibitory effect. The ANS binders in the cytosol were then identified by gel filtration. ANS bound mainly to X and Y (ligandin) fractions in the cytosol. Sulfobromophthalein, which is one of the organic anions exhibiting the in vivo 'counter-transport' phenomenon, remarkably inhibited ANS binding to ligandin fraction. It was thus suggested that the in vivo 'counter-transport' phenomena may be also explained by the enhancement of back diffusion due to the displacement of intracellular binding. In conclusion, one should be more cautious in interpreting data obtained from so-called in vivo 'counter-transport' experiments.     

Direct demonstration of the cross-bridge recovery stroke in muscle thick filaments in aqueous solution by using the hydration chamber

Despite >50 years of research work since the discovery of sliding filament mechanism in muscle contraction, structural details of the coupling of cyclic cross-bridge movement to ATP hydrolysis are not yet fully understood. An example would be whether lever arm tilting on the myosin filament backbone will occur in the absence of actin. The most direct way to elucidate such movement is to record ATP-induced cross-bridge movement in hydrated thick filaments. Using the hydration chamber, with which biological specimens can be kept in an aqueous environment in an electron microscope, we have succeeded in recording ATP-induced cross-bridge movement in hydrated thick filaments consisting of rabbit skeletal muscle myosin, with gold position markers attached to the cross-bridges. The position of individual cross-bridges did not change appreciably with time in the absence of ATP, indicating stability of time-averaged cross-bridge mean position. On application of ATP, individual cross-bridges moved nearly parallel to the filament long axis. The amplitude of the ATP-induced cross-bridge movement showed a peak at 5–7.5 nm. At both sides of the filament bare region, across which the cross-bridge polarity was reversed, the cross-bridges were found to move away from, but not toward, the bare region. Application of ADP produced no appreciable cross-bridge movement. Because ATP reacts rapidly with the cross-bridges (M) to form complex (M·ADP·Pi) with an average lifetime >10 s, the observed cross-bridge movement is associated with reaction, M + ATP → M·ADP·Pi. The cross-bridges were observed to return to their initial position after exhaustion of ATP. These results constitute direct demonstration of the cross-bridge recovery stroke.     

Expression of oncofetal fibronectin messenger ribonucleic acid in fibroblasts in the thyroid: a possible cause of false positive results in molecular-based diagnosis of thyroid carcinomas

Oncofetal fibronectin (onfFN) messenger ribonucleic acid (mRNA) is abundantly expressed in thyroid papillary and anaplastic carcinomas. These carcinomas can be preoperatively diagnosed by the detection of onfFN mRNA in fine needle aspiration biopsies (FNABs). However, previous reports have noted that the expression of onfFN mRNA was observed in 3.7% of the FNABs that were diagnosed as negative cytology. To clarify this discrepancy, we examined the expression of onfFN mRNA in fibroblasts in the thyroid. By RT-PCR and real-time quantitative RT-PCR analyses, we detected a high copy number of onfFN mRNA in cultured fibroblasts obtained from the normal thyroid tissues dissected surgically. Thus, we conclude that the contaminated fibroblasts in FNABs due to tumor necrosis or acute or chronic inflammation may be a cause of false positive results in molecular-based diagnosis of thyroid carcinomas.     

Osteocytes and adhesion molecules

Osteocytes, dendric resident cells in bone, transduce signals of mechanical loading that results in anabolic responses of bone. We have reported the involvement of stretch-activated Ca channels (SA-Cat) in this process. Besides, integrin receptors have been reported to function as mechanosensors. Osteocytes express some adhesion molecules, integrins and CD44, which could mediate signal transduction of mechanical stress as well as osteoblastic differentiation.     

Effect of respiratory acidosis on ventricular shunt flow and hemodynamics in dogs with ventricular septal defect

The effects of respiratory acidosis on ventricular shunt flow and hemodynamics were studied in 20 anesthetized dogs with a ventricular septal defect and a normal pulmonary vascular bed. The interventricular shunt flow was measured directly by using a specially designed electromagnetic flow probe. Respiratory acidosis was produced by hypoventilation and tachypnea with constant minute volume. Hypoxemia was also induced by hypoventilation, but not by tachypnea with constant minute volume. Systemic vascular resistance was increased in severe hypoventilation at 100 and 50 ml of tidal volume, and tachypnea at 100 ml of tidal volume. However the increase of pulmonary vascular resistance was observed in only severe hypoventilation: arterial pH 6.9, PaO2 24 mmHg, and PaCO2 88 mmHg. Left to right ventricular shunt flow and pulmonary blood flow were increased significantly with no change of systemic blood flow in both conditions of respiratory acidosis. The diastolic fraction of shunt flow was increased significantly. These findings indicate that the increase of left to right shunt flow in respiratory acidosis might be one of the risk factors of congestive heart failure for the patients with ventricular septal defect.     

Assessment of inflamed synovial membrane in the knee joint by dynamic magnetic resonance imaging

Dynamic magnetic resonance imaging (dynamic MRI) was used to examine the synovial membrane in the knee joints of 15 patients with rheumatoid arthritis (RA) in order to investigate the relationship between pathological and MRI findings. Signal intensities in the regions of interest (ROI), identified as the synovial membrane of the suprapatellar pouch, were measured on MR images. Signal intensities at various times after the injection of contrast medium Gd–diethylenetriaminopentoacetic acid (Gd–DTPA) were normalized relative to the signal intensity at 80s, and designated as the normalized signal intensity (NSI). Pathological findings were quantified, and the types of inflamed synovial membrane were classified as either acute or chronic. A significant difference in NSI was observed between acute and chronic types (P 0.05). Dynamic MRI was capable of classifying acute and chronic RA by measuring NSI 20s after contrast medium injection. Dynamic MRI was therefore shown to be useful for assessing regional synovial inflammation.