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Facile synthesis of high-efficiency and stable bifunctional electrocatalyst is essential for producing clean hydrogen in energy storage systems. Herein, low Rh-doped flower-like Ni 3 S 2 /Co 3 S 4 heterostructures were facilely prepared on porous nickel foam (labeled Rh-Ni 3 S 2 /Co 3 S 4 /NF) by a hydrothermal method. The correlation of the precursors types with the morphological structures and catalytic properties were rigorously investigated for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the control groups. The low Rh doping within the catalyst played important role in boosting the catalytic characteristics. The resulting catalyst showed the smaller overpotentials of 197 and 78 mV to drive a current density of 10 mA cm -2 for the OER and HER in alkaline electrolyte, respectively. And the potential only required 1.71 V to drive a current density of 100 mA cm -2 in a water splitting device. It reflects excellent overall water splitting of the home-made Rh-Ni 3 S 2 /Co 3 S 4 /NF. This strategy shed some constructive light for preparing transition metal sulfide-based electrocatalysts in water splitting devices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Previous studies have shown that BD patients exhibited impairment when performing a verbal fluency task (VFT) and abnormal prefrontal cortex activation during this task. However, no study has specifically examined whether patients with type II BD demonstrate difficulty in performing VFT and impairments in relevant neural correlates or whether these are related to psychotic symptoms, the present study aimed to examine these issues., Methods: Forty-nine patients with type II BD (21 patients with psychotic symptoms [BDIIp] and 28 patients without psychotic symptoms [BDIIn]) and 45 matched healthy controls (HCs) participated the study and completed the VFTs, while their brain activity was recorded with near-infrared spectroscopy (NIRS)., Results: Both BDIIp and BDIIn patients showed poorer performance on VFTs than HCs. In addition, BDII patients showed lower brain activation than HCs in bilateral dorsolateral prefrontal cortex and right frontal pole, these results were mainly driven by BDIIn patients. Moreover, subjective psychotic symptoms were positively significantly correlated with left dorsolateral prefrontal cortex activation in BDII patients., Conclusions: Type II BD patients showed significant impairment when performing VFTs and reduced activation in the prefrontal cortex, and subjective psychotic symptoms were associated with brain activation in left dorsolateral prefrontal cortex in BDII patients., (Copyright © 2021. Published by Elsevier B.V.)

Service learning experiences abroad provide an excellent opportunity for seasoned health educators to share their skills with underresourced communities in other parts of the world while enriching their own professional development. Health educators have not traditionally participated in short-term medical service trips, which have become a popular humanitarian effort, yet their contributions can expand the scope of these efforts. With our responsibilities often focused on assessing needs, planning, implementing, and evaluation, seasoned health educators can provide guidance for new initiatives and share health promotion materials and other resources with communities in other parts of the world. In this commentary, I detail my experience as the first health educator to volunteer with a medical brigade that has served a rural community in Honduras for nearly two decades, and describe my added contribution of a brief intervention to address teen pregnancy during the brigade's annual, medically oriented visit. I also reflect on the benefits to my professional growth from this opportunity to immerse myself in four very familiar areas of responsibility for health education in a new and unknown setting.

Mental Time Travel (MTT) is the ability of individuals to project themselves to the past or to the future. Studies have shown that schizophrenia (SZ) patients are impaired in MTT. The present study aimed to examine whether MTT in patients with SZ can be improved through Life Review Therapy. Fifty patients with SZ were randomly assigned to the training (SZ-training) or control (SZ-control) group. Whereas the SZ-training group received four-week Life Review Therapy in addition to conventional treatment, the SZ-control group only received conventional treatment. MTT, emotional status, life satisfaction and cognitive functions were assessed before and after the training. We also recruited 25 matched healthy controls to complete all the assessments at baseline. After training, the SZ-training group showed higher specificity and more field perspective than the SZ-control group. No significant difference was found between the SZ-training group post-training assessment and the healthy controls. The SZ-training group also showed significant improvements in emotional expression, semantic memory and verbal fluency, but the SZ-control group did not show such improvements. These results indicated that Life Review Therapy is effective in improving MTT of SZ patients., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The purpose of this study was to explore the experiences, needs, and coping strategies of patients living with heart failure in Singapore. A descriptive qualitative design was used. A purposive sample of 15 informants was recruited from two cardiology wards of a tertiary public hospital in Singapore. Individual face-to-face interviews were conducted with a semistructured interview guideline that was developed based on a review of the literature and a pilot study. Content analysis was adopted to analyze the data, and four main categories were identified: perceived causes, manifestations, and prognosis; enduring emotions; managing the condition; and needs from health care professionals. The informants were overwhelmed with the experience of living with heart failure due to the disruptive and uncertain nature of the condition. This study offers health care professionals practical and useful suggestions when providing holistic care for patients with heart failure., (© The Author(s) 2015.)

Objective: To investigate the diagnosis and treatment of sacrococcygeal teratoma in adults., Methods: The clinical data of 17 patients with sacrococcygeal teratoma confirmed by pathological examination, 9 males and 8 females, aged 20 - 53, were analyzed retrospectively., Result: Correct diagnosis was made pre-operatively in 13 of the 17 patients. Two cases were misdiagnosed as with leiomyoma, and 2 cases as with sacrococcygeal cyst. Pathological examination confirmed the diagnosis of teratoma in all 17 cases. Thirteen patients were followed up for 1 - 5 years post-operatively. Malignant change was seen in 1 case, and 1 patient died 1 year after operation. Two patients suffered a relapse and then fully recovered after re-operation, and the other 15 patients all recovered without relapse., Conclusion: Sacrococcygeal teratoma in adults usually has no typical clinical symptom and signs and is often misdiagnosed. The pathologic examination is the base to make a definite diagnosis. Complete excision is necessary to prevent local recurrence and potential malignant transformation. The sacrococcygeal approach or combined abdominal-sacral approach is recommended.

Study Design: An in vivo model was used to determine levels of mRNA expression in response to direct current (DC) electrical stimulation in a rabbit posterolateral fusion model., Objectives: This study tested the possibility that DC stimulation at the surgery site would increase expression of genes related to bone formation relative to expression in autograft alone., Summary of Background Data: DC electrical stimulation as an adjunct treatment in spinal surgery has shown increased fusion rates when compared with autograft alone, yet the biology of such treatment is not fully understood., Methods: Thirty New Zealand White rabbits were entered into the study. A posterolateral, intertransverse process fusion was performed bilaterally at L4-L5, with autogenous bone graft. An implantable DC stimulator was placed across the decorticated transverse processes before placement of autograft. Animals were killed at 3, 7, 14, 21, and 28 days. mRNA levels of BMP-2, 4, 6, 7, VEGF, FGF-2, TGF-beta, ALK-2, and ALK-3 were evaluated with real-time RT-PCR., Results: mRNA expression was significantly higher in the DC stimulated animals versus the control animals for several of the genes studied. In particular, levels of mRNA were elevated for BMP-2, BMP-6, and BMP-7., Conclusions: This study shows for the first time that DC stimulation results in a sustained increase of multiple osteogenic genes, suggesting that the biologic mechanism for the DC-induced increase in the rate and extent of bone formation observed clinically may be mediated by the up-regulation of these osteoinductive factors.

Electrical stimulation therapies have been used for more than 30 years to enhance spinal fusions. Although their positive effects on spinal fusions have been widely reported, the mechanisms of action of the technologies were only recently identified. Three types of technologies are available clinically: direct current, capacitive coupling, and inductive coupling. The latter is the basis of pulsed electromagnetic fields and combined magnetic fields. This review summarizes the current concepts on the mechanisms of action, animal and clinical studies, and cost justification for the use of electrical stimulation for spinal fusions. Scientific studies support the validity of electrical stimulation treatments. The mechanisms of action of each of the three electrical stimulation therapies are different. New data demonstrates that the upregulation of several growth factors may be responsible for the clinical success seen with the use of such technologies.

The main objective of the current investigation was to regenerate cells of the nucleus pulposus without loss of phenotype. Nucleus pulposus cells were isolated from intervertebral discs from adult rabbits, grown in monolayer culture, and then maintained as a micromass pellet in tube culture. The specimens were evaluated by transmission and light microscopy, reverse transcriptase polymerase chain reaction, and immunohistochemistry. Nucleus pulposus cells proliferated in monolayer culture. When almost confluent, the cells were transferred to a tube and sedimented to form a pellet. The cells reverted to a rounded configuration and formed cell nests surrounded by extensive extracellular matrix, similar to that seen in vivo. These cells did not proliferate. Similar to that observed in situ, cells in pellet culture also expressed aggrecan, CD44, collagen Type II, and collagen Type I, but not collagen Type X, and had low alkaline phosphatase activity. The results of the investigation indicated that nucleus pulposus cells grown in monolayer culture might revert to their original characteristics when transferred to an environment that allows three-dimensional growth, such as upon implantation, a one-step approach. The results also indicated that the two-stage culture procedure might provide an expedient technique to regenerate nucleus pulposus tissue for disc repair.

The characteristics of the nucleus pulposus cells from adult rabbits maintained in in vitro cultures were described in another study. Herein, the authors provide a parallel profile of adult rabbit nucleus pulposus in situ, therefore allowing direct comparisons between in vitro and in situ investigations. Nucleus pulposus specimens from adult rabbits were evaluated using biochemical and immunohistochemical morphologic techniques. The nucleus pulposus from adult rabbits contained cell clusters embedded in proteoglycan-collagen matrix. The cells exhibited a well-defined Golgi system, an extensive endoplasmic reticulum, and a complex vesicular system filled with beaded structures (proteoglycans). Neither necrotic nor apoptotic cells were evident. There was a lack of mitochondria. The extensive extracellular matrix contained amorphous, beaded, and fibrillar components. The fibrillar banding was indicative of Type VI collagen. The nucleus pulposus of adult rabbits expressed aggrecan, collagen Type I and Type II, and CD44, but not collagen Type X and displayed low alkaline phosphatase activity.

The objective of the study was to investigate the capability of bioactive glass 45S5 to serve as a substrate for nucleus pulposus cells in vitro. Nucleus pulposus cells were isolated from adult rabbit discs and seeded onto bioactive glass. At selected time intervals, the cells and glass were evaluated. We found that the cells rapidly attached to the substrate, colonizing it within 12 h. By 21 days, they had formed a lawn of cells over the glass substrate. DNA measurements showed a progressive increase in cell number with time. The phenotype was maintained; the cells expressed aggrecan, and collagen type II and I, but were negative for collagen type X. CD44, a cell-surface glycoprotein that binds hyaluronate, was also expressed by these cells. Electron dispersive X-ray analysis and Fourier transform infrared spectroscopy revealed calcium phosphate-rich layer formation on the substrate surface. The results of this study suggest that nucleus pulposus cell proliferation may be an anchorage dependent event, and that the cells use the calcium phosphate-rich layer to facilitate cell adhesion, and subsequent proliferation. These findings point to the importance of the conditioned bioactive glass as a substrate for nucleus pulposus cells.

Protein adducts are used as markers of chemical exposure. Determination of the clearance rate of these adducts from the blood circulation will provide the time frame for their measurement. Radioactive albumin was prepared biosynthetically by repeated intraperitoneal injections of L-[4,5-3H]lysine to a rat. After an affinity purification, an aliquot of this native [3H-lysine]albumin was adducted with 5 mM acrolein. Both the native albumin (A-treated group) and the albumin-acrolein adduct (AAA-treated group) were intravenously injected to separate groups of rats, and the clearance of radioactivity from the plasma was measured as a function of time. At the end of the experiment (33 h after the injection), radioactivity in the whole plasma, and in homogenates of liver, kidney and spleen and their trichloroacetic acid(TCA)-soluble and -insoluble fractions in both A- and AAA-treated groups, was measured. The results, at the initial 11 h after the injection, showed that the radioactivity was cleared from the circulating plasma more rapidly in the AAA-treated group (32% of the injected radioactivity remained) than the A-treated group (52%). At 33 h after the injection, 22% of the injected radioactivity remained in the plasma in the AAA-treated group as compared to 32% in the A-treated group. The whole homogenates of liver and kidney and their corresponding TCA-soluble fractions showed higher radioactivity in the AAA-treated group as compared to the A-treated group. However, the TCA-insoluble fractions from livers and kidneys of the AAA-treated group showed lower radioactivity as compared to the A-treated group. These results indicated that the albumin-acrolein adduct was removed more rapidly from the circulation than the native albumin, and degraded more rapidly by the liver and kidney. There was no preferential removal or degradation of the adducted albumin by the spleen.

Chemical modifications of human plasma alpha1-antitrypsin with reagents which modify lysyl residues (citraconic anhydride, acetic anhydride, formaldehyde and 2,4,6-trinitrobenzenesulfonic acid) and arginyl residued (1,2-cyclohexanedione) were examined with regard to their effect upon the elastase inhibitory capacity of the glycoprotein. 2,4,6-Trinitrobenzenesulfonic acid was employed to quantitate the remaining free amino groups (epsilon-NH2 groups of lysine) and the extent of modifications. Amino acid analysis was utilized in the same capacity for the guanidino groups of arginyl residues. The elastase inhibitory capacity of alpha1-antitrypsin was destroyed following trinitrophenylation, citraconylation and acetylation. Circular dichroism of the native and modified derivatives revealed major changes in conformation following trinitrophenylation and citraconylation while CD profiles of acetylated and reductively methylated derivatives differed from that of the native profile considerably less. Reductively methylated alpha1-antitrypsin retained its elastatse inhibitory capacity. The reaction of 1,2-cyclohexanedione with alpha1-antitrypsin did not effect in a loss in inhibitory capacity. Gel filtration studies of native and modified alpha1-antitrypsin on Sephadex G-100 demonstrated an increased molecular weight presumably through molecular aggregation, in the citraconylated and trinitrophenylated derivatives, but not in the cases of the other derivatives. Based upon these studies and previous investigations of our laboratory, it was concluded that (1) alpha1-antitrypsin is a lysyl inhibitor type (i.e., the reactive site is a Lys-X bond), (2) its interaction with elastase follows a pattern similar to trypsin and chymotrypsin, and (3) the positively charged epsilon-NH2 group of lysine is essential for the maintenance of elastase inhibitory capacity.

Nitration or acetylation of tyrosine residues of human plasma alpha 1-proteinase inhibitor (alpha 1-PI) with tetranitromethane or N-acetylimidazole resulted in a selective loss of its inhibitory activity. While the chymotrypsin- and trypsin-inhibitory activities were unaffected, all of the elastase inhibiting activity was lost. Comparative amino acid analyses of the native inhibitor and the chemically modified derivatives revealed no differences in the amino acid compositions with the exception that in the case of the tetranitromethane-treated material there were losses in the tyrosine content which could be accounted for by the formation of 3-nitrotyrosine. Nitration of alpha 1-PI.trypsin, alpha 1-PI.chymotrypsin, and alpha 1-PI.elastase complexes with excess tetranitromethane indicated that complex formation protected the binding site of the inhibitor for elastase, but not for trypsin or chymotrypsin. Quantitative estimation of the number of nitrotyrosine residues in the alpha 1-PI isolated from the complexes has shown that one tyrosine residue was protected from nitration. Competition studies have also indicated that the elastase inhibitory site is different from that of trypsin or chymotrypsin, although the possibility of overlapping sites could not be disregarded.

Exposure of alpha 1-PI to nitrous acid resulted in a complete inactivation of either of its elastase or trypsin inhibitors activities. Amino acid analyses of the nitrous acid treated inhibitor revealed only losses of one tryphanyl and three lysyl residues. Reductive methylation of alpha 1-PI offered no protection against loss of activity by nitrous acid. Since no further loss of lysyl residues was observed upon exposure of fully active reductively methylated alpha 1-PI to nitrous acid, modification of one tryptophanyl residue appears to be responsible for the inhibitor's sensitivity to nitrous acid. Absorption spectral studies of the nitrous acid treated alpha 1-PI indicated that the tryptophanyl residue was modified to its N-nitroso derivative.

Evidence is presented to show that inactivation of alpha 1-proteinase inhibitor caused by acrolein depends upon the modification of lysine and histidine residues. Approximately 90% activity was lost when twenty three lysine and eight histidine residues were modified.

1. The nature of the acid-soluble mannosamine intermediates was investigated in bovine thyroid gland slices after incubation with a tracer amount of [14C]mannosamine plus 10 mM carrier mannosamine. 2. These radioactive intermediates were separated by ion exchange, columns, characterized by paper chromatography and were identified as N-acetylmannosamine-6-P. The radioactivity associated with these acid-soluble compounds constituted about 17 percent of the added [14C]mannosamine. 3. [14C]Mannosamine was incorporated as sialic acid only into thyroglobulin.

A plasma alpha 1-proteinase inhibitor was purified, for the first time, from the microsomal fraction of normal human liver by combined procedures of deoxycholate extraction, (NH4)2-SO4 precipitation, gel filtration and immunoadsorbent column chromatographies. The final yield of the material was approx. 15 mg/300 g liver. The preparation was shown to be homogeneous according to polyacrylamide gel electrophoretic and immunological criteria. The estimated molecular weight of the glycoprotein as determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis was 53 000, a value comparable to that reported for plasma alpha 1-proteinase inhibitor. The liver material was, however, devoid of trypsin-, chymotrypsin- or elastase-inhibitory activity. The loss of activity could be due to deoxycholate treatment during the extraction procedure. SDS-polyacrylamide gel electrophoresis of reduced (beta-mercaptoethanol) and alkylated (iodoacetamide) preparation revealed no change in mobility suggesting the presence of only polypeptide chain. The amino acid and carbohydrate compositions of the microsomal material were in close agreement with values reported in the literatures for the corresponding glycoprotein purified from the plasma. The liver microsomal alpha 1-proteinase inhibitor has a single amino terminal residue, namely, glutamic acid, as determined by the dansyl procedure, and a single carboxyl terminal residue, lysine as shown by the carboxypeptidase digestion method. These terminal amino acids are the same as those found in alpha 1-proteinase inhibitor purified from normal human plasma.

Four new peaks were observed upon amino acid analysis of alpha 1-proteinase inhibitor (alpha 1-PI), which was inactivated by acrolein under in vitro conditions. The first peak emerged just before ammonia, the second and third between ammonia and lysine, and the fourth between histidine and arginine. The new fourth peak was also observed when model compounds of lysine (N-acetyllysine or polylysine) were reacted with acrolein and subsequently processed for amino acid analysis. This new compound was purified by high-voltage paper electrophoresis and subjected to fast atom bombardment mass spectrometry, which showed a protonated molecule ion at m/z 203 [M + H]+ followed by m/z 186 [M + H+ - NH3]+. This compound was thus identified as 3-oxopropyllysine, a lysine adduct of acrolein. Similarly, when a model polypeptide of histidine, polyhistidine, was reacted with acrolein under the same conditions as alpha 1-PI, three new peaks (besides histidine) emerged from the column. Their elution times corresponded to the first three new peaks found in the hydrolysates of acrolein treated alpha 1-PI.

A size exclusion column (Spherogel TSK-2000 SW) was utilized in a high-performance size exclusion chromatographic assay to determine the proteinase inhibitory capacity of human sera. Values from assays using this technique agreed well with the standard spectrophotometric inhibitory assays. Nanogram to milligram amounts of protein, namely, alpha 1-proteinase inhibitor, elastase, trypsin, chymotrypsin and their corresponding complexes with the inhibitor, were fractionated in less than 15 min. The nitrated or oxidized alpha 1-proteinase inhibitor was shown to retain its ability to form stable complexes with trypsin or chymotrypsin; however, they lost the inhibitory activity against elastase and instead they behaved as common protein substrates for this enzyme. The present chromatographic procedure was unable to detect any peptide released when the native inhibitor and any of the proteinases reacted to form a complex. Moreover, dissociation of the alpha 1-proteinase inhibitor--elastase complex in an alkaline pH did not result in the formation or release of any peptide.

We have explored the possibility of using glutathione S-transferase (GST) as a biological marker of chemical exposure. All the model compounds tested in the present study (acrolein, propylene oxide, styrene oxide, ethylene dibromide and ethylene dichloride) showed a dose-dependent inactivation of erythrocyte GST in situ as well as the inhibition of purified erythrocyte GST.