Expression and regulation of αB-crystallin in the kidney in vivo and in vitro

αB-crystallin, a major component of the mammalian eye lens, is a small heat shock protein and molecular chaperone that is also abundant in the mammalian kidney. The present study aimed to characterize more closely the intrarenal expression and regulation of αB-crystallin in vivo and in vitro. In normal rat kidney, the expression of αB-crystallin mRNA and protein were both close to the detection limit in cortex, but increased steeply from the outer to the inner medulla where αB-crystallin constitutes approximately 2% of total tissue protein. Immunohistochemistry disclosed papillary collecting duct cells and thin limbs as the major sites for intrapapillary αB-crystallin immunoreactivity. In rats subjected to sucrose diuresis for 3 days, αB-crystallin mRNA expression was reduced by 27 and 46% in outer and inner medulla, respectively. In agreement with the results obtained in vivo, in Madine–Darby canine kidney cells, αB-crystallin mRNA and protein were induced significantly by elevating the medium osmolality to 500 mosm/kg H₂O by the addition of NaCl and raffinose, and also by urea. The NaCl-induced increase in αB-crystallin expression was concentration-dependently blunted by SP600125, a specific JNK inhibitor. Overexpression of αB-crystallin in 293 cells resulted in increased tolerance to acute osmotic stress. These results indicate that αB-crystallin may be regulated by papillary interstitial tonicity in a JNK-dependent process. Moreover, the high abundance of αB-crystallin in the renal medulla may be important for cell survival in an environment characterized by extreme interstitial solute concentrations as present during antidiuresis.     

Hepatitis E in liver transplant recipients in the Rhône-Alpes region in France

Purpose

In developed countries, hepatitis E virus (HEV) is considered an emerging pathogen, but prevalence seems highly variable according to previous European studies. As HEV can lead to chronic infections in immunosuppressed patients, it is thus essential to evaluate the prevalence and incidence of this infection.

Methods

We determined retrospectively, in a cohort of 206 pediatric and adult liver transplant recipients from the Rhône-Alpes region in France, pre-transplant anti-HEV-IgG prevalence and incidence of HEV infections during post-transplant follow-up (HEV IgG and IgM ± HEV-RNA).

Results

Transplantations were carried out between 2005 and 2012 and mean post-transplant follow-up was 32.8 months. Global pre-transplant prevalence of anti-HEV IgG was 29 %, increasing regularly with age from 7 % for children under 15 to 49 % for patients older than 60. From the 142 seronegative patients before transplant, 11 seroconversions (7.7 %) were observed during follow-up (incidence of 2.83 cases per 100 person-years). HEV RNA—tested at transaminases peak or randomly—was detected in only one case of seroconversion. For at least 2 HEV-seropositive patients, who had negative RNAemia before transplantation, viral RNA was detected chronically during follow-up, suggesting reinfection with HEV.

Conclusion

Acute infections were largely more frequent than chronic infections and were asymptomatic or misdiagnosed, suggesting that liver transplant patients may not be particularly prone to developing severe HEV hepatitis. In addition, the presence of IgG anti-HEV may not protect against re-infection. Serological testing, therefore, appears to be of limited interest for the diagnosis of HEV infections in liver transplant recipients.     

Ultrasonics in Medicine

Aug.17At RoomPm 13,00一15,00,15,30一17,00No.7(208)CO一CHAIRMAN Prof。Gao ShangkaiProf。Tsuyoshi ShiinaTITLEABSTRACT PAGES‘尹eial ultrasound probes for eardiae and eardiovaseular diagnosis N .BomFast reeonstru、tion method of refleetion mode difraetiontomographyu几der limited angle eondition T而yoshi Shiina,et al.··········.·..............……。.......……。.Reeonstruetion of the left and right ventrieles and ealeulation of467468CHINESE J.BIOMED.ENG.VOL.2 NO…     

Working Memory in Bees: Also in Flies?

Abstract: Decision making requires reference to both actual and remote information in the context of the requirements of the animal. Here, I explore a cognitive approach to decision making in honeybees and ask the question whether flies may share the faculties observed in bees. Examples are drawn primarily from natural behavior in bees, particularly from navigation and communication. I conclude that studies in Drosophila learning and memory in the tradition of Martin Heisenberg may gain from cognitive concepts, meaning that the “internal doing” of the brain should be included in the search for the neural basis of decision making.     

Changes in PaO_2 and pH in experimental hepatocarcinoma

Changes in PaO_2 and pH in experimental hepatocarcinoma     

Surgical pathology in sub-Saharan Africa—volunteering in Malawi

The breadth of material found in surgical pathology services in African countries differs from the common spectrum of “the West”. We report our experience of a voluntary work in the pathology departments of Blantyre and Lilongwe, Malawi. During a 6-week period, 405 cases (378 histology and 27 cytology cases) were processed. The vast majority showed significant pathological findings (n?=?369; 91.1 %): 175 cases (47.4 %) were non-tumoral conditions with predominance of inflammatory lesions, e.g., schistosomiasis (n?=?11) and tuberculosis (n?=?11). There were 39 (10.6 %) benign tumors or tumor-like lesions. Intraepithelial neoplasia of the cervix uteri dominated among premalignant conditions (n?=?15; 4.1 %). The large group of malignancies (n?=?140; 37.9 %) comprised 11 pediatric tumors (e.g., rhabdomyosarcoma, small blue round cell tumors) and 129 adult tumors. Among women (n?=?76), squamous cell carcinomas (SCCs) of the cervix uteri predominated (n?=?25; 32.9 %), followed by breast carcinomas (n?=?12; 15.8 %) and esophageal SCC (n?=?9; 11.8 %). Males (n?=?53) most often showed SCC of the esophagus (n?=?9; 17.0 %) and of the urinary bladder (n?=?7; 13.2 %). Lymphomas (n?=?7) and Kaposi's sarcomas (n?=?6) were less frequent. Differences compared to the western world include the character of the conditions in general, the spectrum of inflammatory lesions, and the young age of adult tumor patients (median 45 years; range 18–87 years). Providing pathology service in a low-resource country may be handicapped by lack of personnel, inadequate material resources, or insufficient infrastructure. Rotating volunteers offer a bridge for capacity building of both personnel and the local medical service; in addition, the volunteer's horizons are broadened professionally and personally.     

Deficits in adaptive upper limb control in response to trunk perturbations in Parkinson’s disease

The ability of patients with Parkinsons disease (PD) to compensate for unexpected perturbations remains relatively unexplored. To address this issue PD subjects were required to compensate at the arm for an unexpected mechanical perturbation of the trunk while performing a trunk-assisted reach. Twelve healthy and nine PD subjects (off medication) performed trunk-assisted reaching movements without vision or knowledge of results to a remembered target in the ipsilateral (T1) or contralateral (T2) workspace. On 60% of the trials trunk motion was unrestrained (free condition). On the remaining 40% of randomly selected trials trunk motion was arrested at movement onset (blocked condition). If subjects appropriately changed arm joint angles to compensate for the trunk arrest, there should be spatial and temporal invariance in the hand trajectories and in the endpoint errors across conditions. The control group successfully changed their arm configuration in a context-dependent manner which resulted in invariant hand trajectory profiles across the free and blocked conditions. More so, they initiated these changes rapidly after the trunk perturbation (group mean 70 ms). Some PD subjects were unable to maintain invariant hand paths and movement errors across conditions. Their hand velocity profiles were also more variable relative to those of the healthy subjects in the blocked-trunk trials but not in the free-trunk trials. Furthermore, the latency of compensatory changes in arm joint angles in movements toward T1 was longer in the PD group (group mean 153 ms). Finally, PD subjects arm and trunk were desynchronized at movement onset, confirming our previous findings and consistent with PD patients known problems in the sequential or parallel generation of different movement components. The findings that individual PD subjects were unsuccessful or delayed in producing context-dependent responses at the arm to unexpected perturbations of the trunk suggests that the basal ganglia are important nodes in the organization of adaptive behavior.     

Vascularization in Ornamented Osteoderms: Physiological Implications in Ectothermy and Amphibious Lifestyle in the Crocodylomorphs?

Vascularization in the core of crocodylian osteoderms, and in their superficial pits has been hypothesized to be a key feature involved in physiological thermoregulation and/or acidosis buffering during anoxia (apnea). However, up to now, there have been no quantitative data showing that the inner, or superficial, blood supply of the osteoderms is greater than that occurring in neighboring dermal tissues. We provide such data: our results clearly indicate that the vascular networks in both the osteoderms and the pits forming their superficial ornamentation are denser than in the overlying dermis. These results support previous physiological assumptions and indicate that vascularization in pseudosuchian (crocodylians and close relatives) ornamented osteoderms could be part of a broad eco‐physiological adaptation towards ectothermy and aquatic ambush predation acquired by the crocodylomorphs during their post‐Triassic evolution. Moreover, regressions demonstrate that the number of enclosed vessels is correlated with the sectional area of the cavities housing them (superficial pits and inner cavities). These regressions can be used to infer the degree of vascularization on dry and fossilized osteoderms and thus document the evolution of the putative function of the osteoderms in the Pseudosuchia. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:175–183, 2018. © 2017 Wiley Periodicals, Inc.     

Glutamin-Desaminierung in normalen Erythrocyten während Inkubation in vitro

Zusammenfassung Mittels chromatographischer Analyse der freien Aminosäuren der Erythrocyten zeigen Verfasser, daß während der Inkubation bei 37⁰ in den Erythrocyten selbst die Desaminierung des Glutamins mit Bildung von Glutaminsäure stattfindet. Eine Glutaminaseaktivität war bisher für die roten Blutkörperchen noch nicht beschrieben worden. Wahrscheinlich bestehen enge Beziehungen zwischen den glykolytischen Prozessen in den Erythrocyten, der Desaminierung des Glutamins und den Veränderungen der Permeabilität der Erythrocytenmembran in den prälytischen Zuständen.     

Visuomotor learning in immersive 3D virtual reality in Parkinson’s disease and in aging

Successful adaptation to novel sensorimotor contexts critically depends on efficient sensory processing and integration mechanisms, particularly those required to combine visual and proprioceptive inputs. If the basal ganglia are a critical part of specialized circuits that adapt motor behavior to new sensorimotor contexts, then patients who are suffering from basal ganglia dysfunction, as in Parkinson's disease should show sensorimotor learning impairments. However, this issue has been under-explored. We tested the ability of 8 patients with Parkinson's disease (PD), off medication, ten healthy elderly subjects and ten healthy young adults to reach to a remembered 3D location presented in an immersive virtual environment. A multi-phase learning paradigm was used having four conditions: baseline, initial learning, reversal learning and aftereffect. In initial learning, the computer altered the position of a simulated arm endpoint used for movement feedback by shifting its apparent location diagonally, requiring thereby both horizontal and vertical compensations. This visual distortion forced subjects to learn new coordinations between what they saw in the virtual environment and the actual position of their limbs, which they had to derive from proprioceptive information (or efference copy). In reversal learning, the sign of the distortion was reversed. Both elderly subjects and PD patients showed learning phase-dependent difficulties. First, elderly controls were slower than young subjects when learning both dimensions of the initial biaxial discordance. However, their performance improved during reversal learning and as a result elderly and young controls showed similar adaptation rates during reversal learning. Second, in striking contrast to healthy elderly subjects, PD patients were more profoundly impaired during the reversal phase of learning. PD patients were able to learn the initial biaxial discordance but were on average slower than age-matched controls in adapting to the horizontal component of the biaxial discordance. More importantly, when the biaxial discordance was reversed, PD patients were unable to make appropriate movement corrections. Therefore, they showed significantly degraded learning indices relative to age-matched controls for both dimensions of the biaxial discordance. Together, these results suggest that the ability to adapt to a sudden biaxial visuomotor discordance applied in three-dimensional space declines in normal aging and Parkinson disease. Furthermore, the presence of learning rate differences in the PD patients relative to age-matched controls supports an important contribution of basal ganglia-related circuits in learning novel visuomotor coordinations, particularly those in which subjects must learn to adapt to sensorimotor contingencies that were reversed from those just learned.