Imaging of pulmonary emphysema: A pictorial review

The term ‘emphysema’ is generally used in a morphological sense, and therefore imaging modalities have an important role in diagnosing this disease. In particular, high resolution computed tomography (HRCT) is a reliable tool for demonstrating the pathology of emphysema, even in subtle changes within secondary pulmonary lobules. Generally, pulmonary emphysema is classified into three types related to the lobular anatomy: centrilobular emphysema, panlobular emphysema, and paraseptal emphysema. In this pictorial review, we discuss the radiological – pathological correlation in each type of pulmonary emphysema. HRCT of early centrilobular emphysema shows an evenly distributed centrilobular tiny areas of low attenuation with ill-defined borders. With enlargement of the dilated airspace, the surrounding lung parenchyma is compressed, which enables observation of a clear border between the emphysematous area and the normal lung. Because the disease progresses from the centrilobular portion, normal lung parenchyma in the perilobular portion tends to be preserved, even in a case of far-advanced pulmonary emphysema. In panlobular emphysema, HRCT shows either panlobular low attenuation or ill-defined diffuse low attenuation of the lung. Paraseptal emphysema is characterized by subpleural well-defined cystic spaces. Recent topics related to imaging of pulmonary emphysema will also be discussed, including morphometry of the airway in cases of chronic obstructive pulmonary disease, combined pulmonary fibrosis and pulmonary emphysema, and bronchogenic carcinoma associated with bullous lung disease.     

Isolation and characterization of simian immunodeficiency viruses from two subspecies of African green monkeys

Cercopithecus aethiops (African Green monkey), a nonhuman primate species distributed throughout subsaharan Africa, has been shown to have high seroprevalence rates of antibodies to simian immunodeficiency virus (SIV), and therefore, has been proposed as a natural reservoir for immunodeficiency viruses. Our laboratories have isolated SIV-like viruses from two East African subspecies of C. aethiops designated grivet and vervet monkeys. Analysis of the structural proteins based on the molecular weights and immunologic cross-reactivity to the prototypic SIV(MAC), HIV-1, and HIV-2 isolates suggests that these viruses are distinctly different. Heterogeneity was observed in the molecular weights of the gag, pol, and env gene products between SIV isolates from vervets [SIV(AGM(VER))] and grivets [SIV(AGM(GRI))]. Phenotypically, SIV(AGM(VER)) isolates were distinguishable from SIV(AGM(GRI)) isolates by the apparent size difference of the major core antigen p24. All SIV(AGM(GRI)) and SIV(AGM(VER)) isolates were found to encode a transmembrane protein of approximately 40 kD (gp40) in contrast to gp32 of SIV(MAC). Furthermore, the transmembrane protein was shown to be encoded by the entire env open reading frame, unlike gp32 of SIC(MAC) or gp36 of SIV(AGM(TYO-1)). These data indicate that viruses from C. aethiops share common features with SIV(MAC) and HIV-1, but represent diverse SIV-like viruses which may vary according to subspecies and geographic location.     

Effects of movement duration on error compensation in periodic bimanual isometric force production

Recent studies using bimanual force production have examined how factors influence redundancy in the nervous system. The present study examined effects of different movement durations on bimanual force control strategies. Ten healthy male participants produced periodic isometric forces such that the sum of two finger forces was a target cycling between 5 and 10 % of maximum voluntary contraction during five movement durations (500, 750, 1,000, 1,250, and 1,500 ms). Correlations between the two finger forces changed from positive to negative with an increase in duration. The polynomial regression analysis indicates that while the correlations between two finger forces were most negative at the target duration of 1,250 ms, they became more positive as the durations deviated from 1,250 ms. Similarly, while force variability was smallest at the target duration of 1,250 ms, it increased as the durations deviated from 1,250 ms. These findings suggested that while the duration of 1,250 ms might be a natural frequency of both fingers, bimanual force strategies changed from force error compensation to force coupling as the durations deviated from 1,250 ms. In addition, while the variance in the sum of two finger forces (the task-relevant variance) decreased with movement duration, the difference between both the finger forces (the task-irrelevant variance) did not change with the duration. Thus, a decrease in the task-relevant variance with movement duration resulted in the negative correlation between the two finger forces and the small force variability.     

Ultra-Early Induction of General Anesthesia for Reducing Rebleeding Rates in Patients with Aneurysmal Subarachnoid Hemorrhage

ObjectiveRebleeding of aneurysmal subarachnoid hemorrhage (aSAH) is one of the significant risk factors for poor clinical outcome. The rebleeding risk is the highest during the acute phase with an approximate rebleeding rate of 9-17% within the first 24 h. Theoretically, general anesthesia can stabilize a patient's vital signs; however, its effectiveness as initial management for preventing post-aSAH rebleeding remains unclear. The purpose of this study was to determine the feasibility and safety of ultra-early general anesthesia induction for reducing the rebleeding rates among patients with aSAH.Materials and methodsWe retrospectively evaluated patients with aSAH who were admitted to our department between January 2013 and December 2019. All the patients underwent ultra-early general anesthesia induction as initial management regardless of their severity. We evaluated the rebleeding rate before definitive treatment, factors influencing rebleeding, and general anesthesia complications.ResultsWe included 191 patients with two-third of them having a poor clinical grade (World Federation of Neurological Society [WFNS] grade IV or V). The median duration from admission to general anesthesia induction was 22 min. Rebleeding before definitive treatment occurred in nine patients (4.7%). There were significant differences in the Glasgow Coma Scale score (p = 0.047), WFNS grade (p = 0.02), and dissecting aneurysm (p <0.001) between the rebleeding and non-rebleeding patients. There were no cases of unsuccessful tracheal intubation or rebleeding during general anesthesia induction.ConclusionUltra-early general anesthesia induction could be performed safely in patients with aSAH, regardless of the WFNS grade; moreover, it resulted in lower rebleeding rate than that reported in previous epidemiological reports.     

Kv4.3 Channel Dysfunction Contributes to Trigeminal Neuropathic Pain Manifested with Orofacial Cold Hypersensitivity in Rats

Trigeminal neuropathic pain is the most debilitating pain disorder but current treatments including opiates are not effective. A common symptom of trigeminal neuropathic pain is cold allodynia/hyperalgesia or cold hypersensitivity in orofacial area, a region where exposure to cooling temperatures are inevitable in daily life. Mechanisms underlying trigeminal neuropathic pain manifested with cold hypersensitivity are not fully understood. In this study, we investigated trigeminal neuropathic pain in male rats following infraorbital nerve chronic constrictive injury (ION-CCI). Assessed by the orofacial operant behavioral test, ION-CCI animals displayed orofacial cold hypersensitivity. The cold hypersensitivity was associated with the hyperexcitability of small-sized trigeminal ganglion (TG) neurons that innervated orofacial regions. Furthermore, ION-CCI resulted in a reduction of A-type voltage-gated K⁺ currents (IA currents) in these TG neurons. We further showed that these small-sized TG neurons expressed Kv4.3 voltage-gated K⁺ channels, and Kv4.3 expression in these cells was significantly downregulated following ION-CCI. Pharmacological inhibition of Kv4.3 channels with phrixotoxin-2 inhibited IA-currents in these TG neurons and induced orofacial cold hypersensitivity. On the other hand, pharmacological potentiation of Kv4.3 channels amplified IA currents in these TG neurons and alleviated orofacial cold hypersensitivity in ION-CCI rats. Collectively, Kv4.3 downregulation in nociceptive trigeminal afferent fibers may contribute to peripheral cold hypersensitivity following trigeminal nerve injury, and Kv4.3 activators may be clinically useful to alleviate trigeminal neuropathic pain.SIGNIFICANCE STATEMENT Trigeminal neuropathic pain, the most debilitating pain disorder, is often triggered and exacerbated by cooling temperatures. Here, we created infraorbital nerve chronic constrictive injury (ION-CCI) in rats, an animal model of trigeminal neuropathic pain to show that dysfunction of Kv4.3 voltage-gated K⁺ channels in nociceptive-like trigeminal ganglion (TG) neurons underlies the trigeminal neuropathic pain manifested with cold hypersensitivity in orofacial regions. Furthermore, we demonstrate that pharmacological potentiation of Kv4.3 channels can alleviate orofacial cold hypersensitivity in ION-CCI rats. Our results may have clinical implications in trigeminal neuropathic pain in human patients, and Kv4.3 channels may be an effective therapeutic target for this devastating pain disorder.     

Morphological divergence in the curvature of human femoral diaphyses: Tracing the central mass distributions of cross-sections

The diaphysis of the human femoral bone has a physiological anterior curvature; additionally, there is a curvature to the medial side or lateral side. In addition to compression stress from gravity during standing, walking, and running, these bones are continuously exposed to complex stresses from the traction forces of the various strong muscles attached to them. The femoral diaphysis is subjected to these mechanical stresses, and the direction and size of its curvature are defined according to Wolff's law and the mechanostat theory of Frost. The purpose of this study was to quantitatively evaluate the curvature of the femoral diaphysis in Japanese skeletons by determining the curve connecting the central mass distributions (CMD) of cross-sectional images. A total of 90 right femora (46 males and 44 females) were randomly selected from modern Japanese skeletal specimens. Full-length images of these bones were acquired using a clinical computed tomography scanner. The range between the lower end of the lesser trochanter and the adductor tubercle of each femur was divided at regular intervals to obtain ten planes, and nine levels were analyzed. The CMD curve was determined by connecting the CMDs of each of the nine cross-sections. First, the CMD of a cross-section in each of the nine slices was calculated, and the nine trajectories were superimposed from above. Then, by converting the shape of the entire CMD curve to superimpose the coordinates of the endpoint on the starting point, a closed arc representing the curvature of the femur was determined. For both males and females, the patterns varied from mostly medial to largely lateral curvature. The size of the curvature also varied for individuals. By analyzing only the coordinates of the vertex of the CMD curve of each femoral bone, the outlines of the diaphyseal curvatures could be recognized. The femora were thereby divided into two groups: medial bending and lateral bending. Considering males and females together, the number in the lateral-curvature group (n = 51) was larger than that in the medial-curvature group (n = 39). Moreover, the average age of the lateral-curvature group was significantly higher than that of the medial-curvature group (p < 0.05). In males, with an increase in the cortical bone proportion of the cross-sectional area, the anterior vertex of diaphyseal bending tended to be more prominent. This cortical proportion was significantly higher in the medial-curvature groups than in the lateral-curvature group (p < 0.01). The phenomena observed in this study may be related to pathophysiologies such as atypical fractures of the femur and osteoarthritis of the knee joints.     

Mantle cell lymphoma with EBV-positive Hodgkin and Reed–Sternberg-like cells in a patient after autologous PBSCT: Phenotypically distinct but genetically related tumors

The case of 70-year-old man with mantle cell lymphoma (MCL) carrying t(11;14) translocation that relapsed as nodal lymphoma combining MCL and classic Hodgkin lymphoma (cHL) 9 years after autologous peripheral blood stem cell transplant (auto-PBSCT) is reported. Lymph nodes contained two separate areas of MCL and cHL-like components. Hodgkin and Reed–Sternberg (HRS)-like cells were accompanied by a prominent histiocyte background. HRS-like cells were CD5⁻, CD15⁺, CD20⁻, CD30⁺, PAX5⁺, Bob.1⁻, Oct2⁻ and EBER⁺. The MCL component expressed cyclin D1 and SOX11, whereas cyclin D1 and SOX11 expressions were reduced and lost, respectively, in HRS-like cells. Polymerase chain reaction results showed a single clonal rearrangement of the IGH gene in MCL and cHL-like components. CCND1 break apart fluorescence in situ hybridization showed split signals in both MCL and HRS-like cells, suggesting that MCL and cHL-like components were clonally related. Acquisition of p53 expression and Epstein–Barr virus (EBV)-positivity was seen in HRS-like cells. The patient died of disease progression with elevated hepatobiliary enzymes. The autopsy showed both MCL and cHL-like components around the bile ducts, splenic white pulp and bone marrow. The two components were phenotypically distinct, but genetically related, suggesting that transformation of MCL to HRS-like cells during the course of MCL in association with EBV infection.     

Development of a valve type semi-closed extracorporeal circulation system

Journal of Artificial Organs - In Japan, perfusionists who work on other clinical tasks are involved in cardiopulmonary bypass. Moreover, the number of cases they can perform is limited. In view of...