Successful treatment of severe subcutaneous insulin resistance with inhaled insulin therapy

van Alfen‐van der Velden AAEM, Noordam C, de Galan BE, Hoorweg‐Nijman JJG, Voorhoeve PG, Westerlaken C. Successful treatment of severe subcutaneous insulin resistance with inhaled insulin therapy. The potential of inhaled insulin therapy for severe resistance to subcutaneous insulin was tested in a 7‐yr old boy with type 1 diabetes mellitus. The efficiency of 1 mg inhaled insulin (Exubera^®) was examined by a 4‐h euglycemic clamp study. During the clamp, the glucose infusion rate started to increase 25 min after inhalation and peaked 120 min after inhalation. Subsequently, a trial of inhaled insulin monotherapy was initiated consisting of pre‐meal inhalations and one inhalation during the night. Since glycemic control remained fair (HbA1c ～8.5%), this therapy was continued. Over the ensuing 18 months, mild keto‐acidosis occurred twice during gastro‐enteritis. Inhaled insulin was well tolerated and pulmonary function did not deteriorate. We conclude that severe resistance to subcutaneous insulin does not preclude sufficient absorption of insulin delivered by pulmonary.     

Burn depth assessment by dual-wavelength light emitting diodes-excited photoacoustic imaging in rats

Accurate burn depth assessment is crucial to determine treatment plans for burn patients. We have previously proposed a method for performing burn depth assessments based on photoacoustic (PA) imaging, and we have demonstrated the validity of this method, which allows the successful detection of PA signals originating from the blood under the bloodless burned tissue, using rat burn models. Based on these findings, we started a clinical study in which we faced two technical issues: (1) When the burn depth was shallow, PA signals due to skin contamination and/or melanin in the epidermis (surface signals) could not be distinguished from PA signals originating from the blood in the dermis; (2) the size of the system was too large. To solve these issues, we propose a burn depth diagnosis based on dual-wavelength light emitting diodes (LEDs)-excited PA imaging. The use of LEDs rendered the system compact compared to the previous one that used a conventional solid-state laser. We replicated human burned skin by applying a titrated synthetic melanin solution onto the wound surface in albino rat burn models and measured their burn depths by PA excitation at 690 and 850 nm, where melanin and haemoglobin show greatly different absorption coefficients. As a result, the surface signals were eliminated by subtracting the PA signals at 690 nm from those at 850 nm. The resultant estimated burn depths were strongly correlated with the histological assessment results. The validity of the proposed method was also examined using a burn model of rats with real melanin.     

Dynamic particle image velocimetry flow analysis of the flow field immediately downstream of bileaflet mechanical mitral prostheses

New dynamic particle image velocimetry (PIV) technology was applied to the study of the flow field associated with prosthetic heart valves. Four bileaflet prostheses, the St. Jude Medical (SJM) valve, the On-X valve with straight leaflets, the Jyros (JR) valve, and the Edwards MIRA (MIRA) valve with curved leaflets, were tested in the mitral position under pulsatile flow conditions to find the effect of the leaflet shape and overall valve design on the flow field, particularly in terms of the turbulent stress distribution, which may influence hemolysis, platelet activation, and thrombus formation. Comparison of the time-resolved flow fields associated with the opening, accelerating, peak, and closing phases of the diastolic flow revealed the effects of the leaflet shape and overall valve design on the flow field. Anatomically and antianatomically oriented bileaflet valves were also compared in the mitral position to study the effects of the orientation on the downstream flow field. The experimental program used a dynamic PIV system utilizing a high-speed, high-resolution video camera to map the true time-resolved velocity field inside the simulated ventricle. Based on the experimental data, the following general conclusions can be made. High-resolution dynamic PIV can capture true chronological changes in the velocity and turbulence fields. In the vertical measuring plane that passes the centers of both the aortic and mitral valves (A-A section), bileaflet valves show clear and simple circulatory flow patterns when the valve is installed in the antianatomical orientation. The SJM, the On-X, and the MIRA valves maintain a relatively high velocity through the central orifice. The curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow phases when the valve is installed in the anatomical orientation. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where characteristic differences in valve design on the three-dimensional flow should be visible, the symmetrical divergent nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation was evident. The SJM valve, with a central downward flow near the valve, is contrasted with the JR valve, which has a peripherally strong downward circulation with higher turbulent stresses. The On-X valve has a strong central downward flow attributable to its large opening angle and flared inlet shape. The MIRA valve also has a relatively strong downward central flow. The MIRA valve, however, diverts the flow three-dimensionally due to its peripherally curved leaflets.     

A challenge of deep-learning-based object detection for hair follicle dataset

Background

Deep-learning object detection has been applied in various industries, including healthcare, to address hair loss.

Methods

In this paper, YOLOv5 object detection algorithm was used to detect hair follicles in a small and specific image dataset collected using a specialized camera on the scalp of individuals with different ages, regions, and genders. The performance of YOLOv5 was compared with other popular object detection models.

Results

YOLOv5 performed well in the detection of hair follicles, and the follicles were classified into five classes based on the number of hairs and the type of hair contained. In single-class object detection experiments, a smaller batch size and the smallest YOLOv5s model achieved the best results, with an map of 0.8151. In multiclass object detection experiments, the larger YOLOv5l model was able to achieve the best results, and batch size affected the result of model training.

Conclusion

YOLOv5 is a promising algorithm for detecting hair follicles in a small and specific image dataset, and its performance is comparable to other popular object detection models. However, the challenges of small-scale data and sample imbalance need to be addressed to improve the performance of target detection algorithms.     

Handheld microfocused ultrasound device for facial lifting: A preliminary study of ULTIGHT

Objective

Although focused ultrasound modalities have achieved positive clinical results in noninvasive skin rejuvenation, they presented various side effects and particularly severe pain during treatment. This study introduces a microfocused ultrasound (MFU) device, ULTIGHT, to overcome the severe pain issue, providing quasi-facial lifting.

Materials and Methods

Transducer surface was imaged with a scanning electron microscope. The energies of four treatment cartridges were measured using an ultrasound power meter. In vitro experiments were performed to quantitatively evaluate the MFU thermal zones (MFUTZs) and treatment line (TL) of 10 MFUTZs. Ex vivo experiments were performed to evaluate the MFUTZs and temperature rise in tissue. Clinical trials using eight volunteers were performed to qualitatively evaluate facial lifting.

Results

The MFU transducer clearly showed a smooth and no air gap surface. ULTIGHT produced 10 discrete MFUTZs in a TL of length 10 mm. In ex vivo tissue, discrete linear MFUTZs were clearly observed at lower number of TLs; however, they started to aggregate at higher number of TLs. The temperature rise was linearly increased as a function of the number of treatments. A single MFUTZ resulted in a temperature rise of 3°C–10°C that could cause hyperthermia for body temperature. In the clinical trials, the volunteers showed quasi-facial lifting right after treatment on the lower facial region.

Conclusions

ULTIGHT provides relatively low energy, which may be advantageous or disadvantageous depending on clinical applications. Additionally, it has the advantage of being pain-free even without anesthetic during treatment, providing quasi-facial lifting right after treatment.     

Role of nitric oxide in regulation of coronary blood flow during myocardial ischemia in dogs

Objectives. This study was undertaken to examine whether nitric oxide released in ischemic myocardium decreases the coronary vascular resistance and attenuates the severity of contractile and metabolic dysfunction.Background. Endothelium-derived relaxing factor, recently identified as nitric oxide, is a potent relaxant of coronary smooth muscle.Methods. The left anrterior descending coronary artery was perfused through an extracorporeal bypass tube placed in the carotid artery in 56 open chest dogs. After hemodynamic stabilization, we occluded this bypass tube to decrease coronary blood flow to one third of the control flow. Thereafter, we maintained a constant coronary perfusion pressure(40.9 ± 3.1mm Hg).Results. Under ischemic conditions, the coronary arteriovenous differences in nitrate and nitrite (end products of nitric oxide) increased (from 3.5 ± 0.4 [mean ± SEM] to 12.9 ± 2.1 μmol/liter, p < 0.01). ⁰-Monomethyl -arginine (3 μg/kg body weight per min, intracoronary) decreased the coronary arteriovenous differences in nitrate and nitrite (5.0 ± 0.9 μmol/liter, p < 0.05) and coronary blood flow (from 29.8 ± 0.5 to 18.1 ± 1.1 ml/100 g per min, p < 0.001). Fractional shortening (from 3.7 ± 1.0 to −1.3 ± 0.7%, p < 0.001) and lactate extraction ration (from −44.0 ± 4.1 to −59.2 ± 4.9%, p < 0.005) of the perfused area also decreased. These values were restored by the concomitant administration of -arginine. Blood flow to the endomyocardium was decreased relative to the epimyocardium. A reduction in coronary blood flow and worsening of myocardial contractile and metabolic functions due to the administration of ^G-monomethyl -arginine during ischemia were observed in denervated hearts. A reduction in coronary blood flow in ischemic myocardium was observed with the administration of ^W-nitro- -arginene methyl ester as well, although neither ^W-nitro- -arginine methyl ester nor ^G-monomethyl -arginine changed coronary blood flow and myocardial contractile and metabolic functions in the nonischemic myocardium. The cyclic guanosine monophosphate content of epicardial coronary artery increased due to myocardial ischemia; this increased was attenuated with ^G-monomethyl -arginine treatment.Conclusions. We conclude that endogenous nitric oxide predominantly decreases the coronary vascular resistance of ischemic endomyocardium, thereby improving myocardial contractility and metabolic function.