Hepatic and renal histology and mercury concentrations of North West and North East Greenland narwhals (Monodon monoceros)

Narwhals (Monodon monoceros) are at the top of the Arctic food web and therefore might biomagnify high total mercury (Hg) concentrations in organs and tissues. The aim of this study was to determine histopathology and Hg concentrations in liver and kidneys from 15 North East Greenland narwhals (3 subadult females, 8 adult females, 3 subadult males, and 1 adult male) and compare data with previous observations of 12 North West Greenland specimens (1 subadult female, 4 adult females, 1 subadult male, and 6 adult males). The zoological length was significantly larger and hepatic and renal concentrations significantly higher in adults compared to subadults. When comparing tissues, the Hg levels were significantly the highest in liver, while a correlation between metal levels in liver and kidneys was positive and significant. Histological examination of renal tissues presented four types of glomerular lesions (capillary dilatation [0–100%], membrane thickening [0–100%], dilatation of space [0–80%], and sclerosis [0–70%]) and two tubular lesions (atrophy/hyalinization [0–40%] and casts [0–60%]). Hepatic tissues exhibited three portal lesions (fibrosis [0–33%], cell infiltrates [0–40%], and bile duct proliferation [0–40%]) and two parenchymal lesions (steatosis [83–100%] and lipid-filled Ito cells [0–33%]). All 12 lesions were found in adult whales from North West Greenland while eight were present in adult whales from North East Greenland. Six lesions were detected in subadults from North East Greenland and four in subadults from North West Greenland. A significantly higher frequency of dilatation and hyalinization of Bowman’s space and capsule and glomerular capillary dilatation was found in adult narwhals from West Greenland. There was no marked difference in Hg concentrations in whales with and without histological lesions. In conclusion, the prevalence of histological changes and Hg levels were the highest in adults and therefore both age and metal are important factors to include when evaluating liver and kidney lesions in narwhals.     

Vitiligo in children and adolescents: association with thyroid dysfunction

Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group.     

Perspectives on phytoremediation of zinc pollution in air,water and soil

In this article, we discuss the phytoremediation of Zn pollution in the environment and the mechanism of plant resistance focusing on the mycorrhiza and subcellular mechanisms affecting metal binding and efflux in plants. Phytoremediation is a green low-cost technology that use plants to remove heavy metals (HMs) from soil. As part of this, it is necessary to consider the plant's tolerance to for example zinc (Zn) together with the plant's ability to accumulate and adapt to the specific local environment. During the process of restoring ecosystem contaminations, pH, organic matter, root exudates and microbial biomass affect the efficiency of phytoremediation while considering chemical modification, biosynthesis, microbial assistance and gene technology. However, obstacles remain in terms of for example chemical modifications that may cause either new pollution or disrupt the plant-microorganism symbiosis while other applications such as genetic engineering to change plant traits and function thereby improving heavy metal tolerance and absorption. The selection of gene fragments is complicated and requiring careful considerations due to environmental and human health side effects. Furthermore, using biochar may help to reduce the costs and increase the efficiency of plant phytoremediation. At the same time, there is an urgent need to combine nanotechnology and use of artificial chelating agents and plant hormones to screen the microbiome conducive to plant Zn absorption in order to improve the efficiency of phytoremediation.     

Mental health disorder,pain, and pain treatment among long-term care residents: Evidence from the Minimum Data Set 3.0

Objective: This study evaluated: (a) associations between long-term care residents’ mental health disorder diagnoses and their pain self-reports and pain treatments, and (b) the extent to which communication, cognitive, and physical functioning problems help explain disparities in the pain and pain treatments of long-term care residents with and without mental health disorders.

Method: Minimum Data Set 3.0 records of 8,300 residents of Department of Veterans Affairs Community Living Centers were used to determine statistically unadjusted and adjusted cross-sectional associations between residents' mental health diagnoses and their pain and pain treatments.

Results: Residents diagnosed with dementia and serious mental illness (SMI) were less likely, and those diagnosed with depressive disorder, post-traumatic stress disorder (PTSD), and substance use disorder (SUD) were more likely, to report recent, severe, and debilitating pain. Among residents affirming recent pain, those with dementia or SMI diagnoses were twice as likely to obtain no treatment for their pain and significantly less likely to receive as-needed pain medication and non-pharmacological pain treatments than were other residents. Those with either depressive disorder or PTSD were more likely, and those with SUD less likely, to obtain scheduled pain medication. In general, these associations remained even after statistically adjusting for residents' demographic characteristics, other mental health disorder diagnoses, and functioning.

Conclusion: Long-term care residents with mental health disorders experience disparities in pain and pain treatment that are not well-explained by their functioning deficits. They may benefit from more frequent, thorough pain assessments and from more varied and closely tailored pain treatment approaches.     

Human burst-forming units-erythroid need direct interaction with stem cell factor for further development

To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation.     

Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function

Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.     

Red cell membrane stiffness in iron deficiency

The purpose of this study was to characterize red blood cell (RBC) deformability by iron deficiency. We measured RBC deformability to ektacytometry, a laser diffraction method for determining the elongation of suspended red cells subjected to shear stress. Isotonic deformability of RBC from iron-deficient human subjects was consistently and significantly lower than that of normal controls. In groups of rats with severe and moderate dietary iron deficiency, RBC deformability was also reduced in proportion to the severity of iron deficiency. At any given shear stress value, deformability of resealed RBC ghosts from both iron-deficient humans and rats was lower than that of control ghosts. However, increase of applied shear stress resulted in progressive increase in ghost deformation, indicating that ghost deformability was primarily limited by membrane stiffness rather than by reduced surface area-to-volume ratio. This was consistent with the finding that iron-deficient cells had a normal membrane surface area. In addition, the reduced mean corpuscular hemoglobin concentration (MCHC) and buoyant density of the iron-deficient rat cells indicated that a high hemoglobin concentration was not responsible for impaired whole cell deformability. Biochemical studies of rat RBC showed increased membrane lipid and protein crosslinking and reduced intracellular cation content, findings that are consistent with in vivo peroxidative damage. RBC from iron-deficient rats incubated in vitro with hydrogen peroxide showed increased generation of malonyldialdehyde, an end-product of lipid peroxidation, compared to control RBC. Taken together, these findings suggest that peroxidation could contribute in part to increased membrane stiffness in iron- deficient RBC. This reduced membrane deformability may in turn contribute to impaired red cell survival in iron deficiency.     

Patients with Persistent Atrial Fibrillation Taking Oral Verapamil Exhibit a Lower Atrial Frequency on the ECG

Background: While there is agreement that verapamil attenuates the AF‐ induced refractory period shortening when given before AF induction, controversy exists regarding its effects when given after the onset of persistent AF. This study aimed to compare atrial fibrillatory frequency obtained from the surface ECG in patients with persistent atrial fibrillation (AF) with oral verapamil treatment to those without this treatment. Methods and Results: Surface ECG recordings were performed in 57 patients (34 male, 23 female, mean age 59 ± 11 years) with persistent AF (> 7 days). The frequency content of the fibrillatory baseline was quantified using digital signal processing (filtering, QRST complex averaging and subtraction. Fourier transformation). In 27 patients with verapamil treatment (120 or 240 mg/day for at least 7 days) mean fibrillatory frequency measured 6.4 ± 0.2 Hz, compared to 7.0 ± 0.4 Hz (P = 0.012) in 30 patients without verapamil. In a subset of 20 randomly selected patients (10 with, 10 without verapamil treatment) a 24‐hour Holter ECG recording was performed and fibrillatory frequency determined at 4 PM, 10 PM, 4 AM, and 10 AM. While there was a significant frequency reduction in the verapamil treated patients at night (P = 0.011), it remained constant over time in the other patients. Conclusion: In patients with persistent AF, fibrillatory frequency assessed by spectral analysis of the surface ECG is lower in patients taking verapamil. A.N.E. 2002;7(2):92–97     

Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms

We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis.