Transcriptome analysis endoplasmic reticulum-stress response in Litopenaeus vannamei hemocytes

Numerous studies have proved that endoplasmic reticulum (ER)-stress is an important cause of aquatic animal diseases. Therefore, for effectively preventing and controlling aquatic animal diseases, a systematic and in-depth understanding of the environmental stress response in aquatic animals is necessary. In present study, the influence of ER-stress in Litopenaeus vannamei was investigated using Illumina HiSeq based RNA-Seq. Comparing to the cDNA library of hemocytes treated with DMSO in L. vannamei, 286 unigenes were significantly upregulated and 473 unigenes were significantly down-regulated in the Thapsigargin treated group. KEGG analysis indicated that the differentially expressed genes (DEGs) are mainly related to ER-stress, immune as well as metabolism. Besides the classical ER-stress response pathways, the regulation of cell cycle and DNA replication are also important measures of ER-stress response. It has been suggested that the influence of ER-stress on immune genes might be an important factor in environmental stress inducing shrimp disease. Our investigation exhibited that immune-related DEG Prophenoloxidase activating enzyme 2 (LvPPAE2) roled in anti-pathogen immunity of shrimp. This study provides a solid foundation for uncovering the environmental adaptation response and especially its relationship with L. vannamei immune system.

A IFI27 gene contributes to ER-stress mediated apoptosis and benefits for white spot syndrome virus infection in Litopenaeus vannamei

The interplay between virus and host has been one of the hot spot in virology, and it is also the important aspect of revealing the mechanism of virus infection. Increasing studies revealed that several key molecules took part in the process of virus-host interaction. White spot syndrome virus (WSSV) has been proved to affect several physiological processes of the host cells, especially apoptosis. While the relationship between them still remains unclear. In this study, a IFI27 gene (LvIFI27) of Litopenaeus vannamei was cloned. It is indicated that LvIFI27 was induced upon endoplasmic reticulum (ER)-stress and unfolded protein response activator Thapsigargin. Unlike human IFI27 locating to mitochondria, LvIFI27 lied to ER, and was involved in cell apoptosis process. Moreover, results of cumulative mortality analysis showed that LvIFI27 might contributed to WSSV proliferation by promoting apoptosis during the process of viral infection. Findings in this study enriched our understanding of the relationship between WSSV infection and ER-stress mediated apoptosis.

Transcriptome analysis of the influence of high plant protein based diet on Trachinotus ovatus liver

Seeking out fish meal (FM) alternatives is an important requirement for aquaculture all over the world. And most practitioners believe that the plant protein is most potential for FM surrenal. While high plant protein feed caused some common problems in aquatic livestock: the absorption rate and growth rate are decreased, and even caused digestive tract inflammation. In present study, the inflence of high plant protien feed in Trachinotus ovatus was investigated using illumina HiSeqTM2000 based RNA-Seq. By comparing the two groups of cDNA libraries developed from high plant protien based diet or FM based diet fed T. ovatus livers, 836 unigenes were significantly upregulated, and 345 were significantly down regulated. KEGG analysis indicated that the differentially expressed genes (DEGs) are mainly metabolic-related genes. It was found that more than 28 DGEs beloned to the protein metabolism and absorption, lipid biosynthesis or other metabolic pathways. It indicated that high plant protein based diet had broad effects on metabolism on T. ovatus. There were also more DEGs belong to immune-related signaling pathways, include genes were involved in pathpathogen resistance and genes related to immunity system. These DEGs provided useful clues to explore the mechanisms that high plant protein based diet caused side effects on T. ovatus. These results improved our current understanding of the response of high plant protein based diet in T. ovatus, and outstanding the reasons of the side effect caused by high protein based diet.

Litopenaeus vannamei Sma and Mad related protein 5 gene is involved in stress response and white spot syndrome virus infection

Cell survival is based on the stability of intracellular state. It was well known that biochemical reactions in cells require specific intracellular environments, such as pH and calcium concentration. While the mechanism of stabilizing the intracellular environment is complex and far from clear. In this study, a Sma and Mad related protein 5 gene (LvSmad5) of Litopenaeus vannamei was cloned. LvSmad5 was located to both cytoplasm and nucleus. And subcellular localization of LvSmad5 was responsed to the changing of cells internal and external environment. Besides, it was found that subcellular localization of LvSmad5 was also regulated by unfolded protein response. Moreover, it was proved that nucleic localization of LvSmad5 could significantly increase the white spot syndrome virus (WSSV) infection in shrimp, and knockdown expression of LvSmad5 decreased the cumulative mortality of WSSV infection shrimp. Further investigation revealed that cytoplasm LvSmad5 could interplay with shrimp hexokinase 1, and contribute to glycolysis. These results indicated that LvSmad5 played a role in L. vannamei environmental stress response, and was used by WSSV for its replication.

A Litopenaeus vannamei TRIM32 gene is involved in oxidative stress response and innate immunity

Tripartite motif (TRIM) family proteins are named by the presence of tripartite motifs in their amino terminal domains. Apart from the amino terminal, their carboxyl terminal contain variable domains which mediate diverse functions of the TRIM proteins. It had been found that TRIM proteins played important roles in distinct biological processes, such as innate immunity, anti-tumor immunity, cell cycle regulation and so on. In the present study, we cloned a TRIM32 (LvTRIM32) gene from Litopenaeus vannamei. LvTRIM32 was highly expressed in hemocytes, gills and epidermis, and subcellular localization analysis indicated that it was widely distributed in S2 cells. In vitro ubiquitination assays indicated that LvTRIM32 had E3 ubiquitin ligase activity. Results of real-time RT-PCR assay showed that LvTRIM32 was induced in shrimp hemocytes upon oxidative stress. It was also proved that the promoter activity of LvTRIM32 was enhanced by NF-E2-related factor, and knocked-down expression of LvTRIM32 depressed the expression of malic enzyme and epoxide hydrolase. Downregulated LvTRIM32 suppressed the cumulative mortality of shrimp under oxidative stress. Moreover, it was found that LvTRIM32 could be induced in shrimp hemocytes upon immunostimulation, and downregulated LvTRIM32 increased the cumulative mortality of shrimp infected with white spot syndrome virus (WSSV) or Vibrio alginolyticus. Collecting results suggested that LvTRIM32 was a member of shrimp antioxidant stress system, and it was also involved in WSSV- or V. alginolyticus-infection resistance.

Identification and functional characterization of a C-type lectin gene from Litopenaeus vannamei that is associated with ER-stress response

C-type lectins (CTLs), which bind carbohydrates in a Ca²⁺-dependent manner, are involved in many cellular activities, especially immunity. CTLs play important roles in both the antibacterial and the antiviral immune response and are also associated with autoimmunity. Several CTLs have been investigated in crustaceans, primarily with respect to their function in the immune response. In this study, we cloned a novel CTL gene (LvCTLU) from Litopenaeus vannamei. LvCTLU is involved in microbe agglutination and phagocytosis. Downregulating LvCTLU increased the cumulative mortality of L. vannamei after Vibrio parahemolyticus infection. Similar to other reported CTLs, LvCTLU also had antiviral properties. Downregulation of LvCTLU also increased the cumulative mortality of L. vannamei after infection with white spot syndrome virus. More importantly, LvCTLU expression was induced by the unfolded protein response (UPR), which is the key pathway in the endoplasmic reticulum (ER)-stress response of eukaryotic organism. Our results suggested that this protein might be involved in the shrimp ER-stress response. Reporter gene assay indicated that LvCTLU was regulated by X-box-binding protein 1, which is the key transcription factor in the UPR. Our study thus revealed that LvCTLU plays vital roles in both the anti-pathogen immune response and the ER-stress response.

Growth of multiple metal/semiconductor nanoheterostructures through point and line contact reactions

Forming functional circuit components in future nanotechnology requires systematic studies of solid-state chemical reactions in the nanoscale. Here, we report efficient and unique methods, point and line contact reactions on Si nanowires, fabricating high quality and quantity of multiple nanoheterostructures of NiSi/Si and investigation of NiSi formation in nanoscale. By using the point contact reaction between several Ni nanodots and a Si nanowire carried out in situ in an ultrahigh vacuum transmission electron microscopy, multiple sections of single-crystal NiSi and Si with very sharp interfaces were produced in a Si nanowire. Owing to the supply limited point contact reaction, we propose that the nucleation and growth of the sugar cane-type NiSi grains start at the middle of the point contacts between two Ni nanodots and a Si nanowire. The reaction happens by the dissolution of Ni into the Si nanowire at the point contacts and by interstitial diffusion of Ni atoms within a Si nanowire. The growth of NiSi stops as the amount of Ni in the Ni nanodots is consumed. Additionally, without lithography, utilizing the line contact reaction between PS nanosphere-mediated Ni nanopatterns and a nanowire of Si, we have fabricated periodic multi-NiSi/Si/NiSi heterostructure nanonowires that may enhance the development of circuit elements in nanoscale electronic devices. Unlike the point contact reaction, silicide growth starts at the contact area in the line contact reaction; the different silicide formation modes resulting from point and line contact reactions are compared and analyzed. A mechanism on the basis of flux divergence is proposed for controlling the growth of the nano-multiheterostructures.

Resonantly pumped high power flat L-band erbium-doped superfluorescent fiber source

An all-single-mode-fiber L-band superfluorescent fiber source (SFS) with 1 W output power, 34.3 nm bandwidth (FWHM) and 54% optical conversion efficiency is constructed by seeding a high power erbium-doped fiber amplifier (EDFA) with a low power L-band ASE seed source to avoid parasitic lasing. The source is resonantly pumped by a high power C-band SFS peaked at 1545 nm.

Apoptotic markers on lymphocytes and monocytes are unchanged during single hemodialysis sessions using either regenerated cellulose or polysulfone membranes

BACKGROUND

There is an increased rate of apoptosis of peripheral blood mononuclear cells (PBMCs) in patients undergoing hemodialysis (HD), but little is known about how different dialysis membranes may contribute to the process. We, therefore, studied the influence of two different dialysis membranes on apoptotic markers during HD.

METHODS

8 healthy controls and 8 patients on regular HD 3 times per week were enrolled in this cross-controlled study. Patients received HD using polysulfone and then regenerated cellulose dialysis membranes for one week each, sequentially. Serum was collected for C-reactive protein (CRP) detection; flow cytometry with dual antibody staining was used to measure the apoptotic markers Fas (CD95), FasL (CD 178) and TNF-R2 (CD120b) in T cells (CD3+), B cells (CD19+), and monocytes (CD14+) at 0, 15, 120 and 240 min after starting HD. We also measured total leukocyte numbers and differential white cell counts.

RESULTS

Hemodialysis patients revealed lymphocytopenia, monocytopenia, higher CRP levels and higher Fas and TNF-R2 expression on lymphocytes and monocytes at baseline when compared with normal controls. Leukocyte numbers, including neutrophils, lymphocytes and monocytes, dropped significantly after 15 min of dialysis. There were no significant differences in Fas levels during hemodialysis on T and B lymphocytes or on monocytes. T lymphocyte FasL (CD 178) levels remained unchanged throughout the process. There was a significantly lower overall level of CD120b at 15 min of HD, whereas this marker was higher on monocytes after dialysis. There were no significant differences in the levels of apoptotic markers between the two membranes.

CONCLUSION

Our results suggest that uremia itself contributes to PBMC apoptosis. The two different dialysis membranes used in this study did not influence apoptotic markers on PBMCs significantly, but increased TNF-R2 expression on monocytes during a single dialysis session.

Branch arm filtered coherent combining of tunable fiber lasers

A branch arm filtering technique is firstly proposed and experimentally demonstrated. A tunable band pass filter is inserted into one branch arm of the Mach-Zehnder type resonator instead of into the common arm as usual, in the coherent combining of two tunable fiber lasers. The arrangement improves the efficiency of the laser without obvious spectral quality penalty. The laser can be tuned from 1530 nm to 1570 nm with little power fluctuation, which is limited by the tuning range of the filter. A novel scaling scheme is also proposed, allowing the technique to be applied to the tuning of an extremely high power laser with a low power filter. The technique is expected to be compatible with other kinds of lasers such as linearly polarized lasers, Michelson type resonator and bulk lasers as well.

Watt-level L band superfluorescent fiber source

An L band superfluorescent fiber source (SFS) with output power of 0.94W is presented, under 4.4W 976nm pump power. The optical conversion efficiency is about 21%. The spectrum covers the broad wavelength range from 1560nm to 1615nm. The high power L band SFS is constructed by a low power L band amplified spontaneous emission (ASE) seed source and a high power erbium-ytterbium co-doped fiber (EYDF) amplifier in double pass forward pumping configuration.

Tunable high-peak-power, high-energy hybrid Q-switched double-clad fiber laser

A cw laser-diode-pumped Yb-doped double-clad fiber laser operating in a hybrid Q-switched regime was demonstrated. The output pulses had a duration as short as 4.2 ns, a tunable wavelength range from 1080.8 to 1142.7 nm, and a linewidth of less than 0.05 nm. Maximum peak power of approximately 175 kW and single-pulse energy of 1.57 mJ were obtained.

Narrow-linewidth widely tunable hybrid Q-switched double-clad fiber laser

A laser-diode-pumped Yb-doped double-clad fiber laser operating in a hybrid Q-switched regime has been demonstrated. With pulsed pump light and stimulated Brillouin scattering of the gain fiber as the Q-switching mechanisms, the laser generated nanosecond pulses with a stable repetition rate. A single-pulse energy of as much as 143.1 microJ with a peak power of 28.6 kW was obtained. Use of an external-cavity diffraction grating in the Littman configuration permitted tuning of the laser wavelength over a 15.7-THz range from 1080 to 1140 nm, and a linewidth of 0.04 nm over the whole tuning range was achieved.

Prevention of obliterative airway disease in HLA-A2-transgenic tracheal allografts by neutralization of tumor necrosis factor

BACKGROUND

Inflammatory cytokines play an important role in the development of experimental obliterative airway disease (OAD) after transplantation. To further determine the immunologic mechanisms associated with OAD development, we used a murine tracheal transplant model in which a single mismatched HLA-A2-transgenic molecule is indirectly recognized by the recipient CD4+ T cells and then determined whether neutralization of several inflammatory cytokines affected the development of OAD.

METHODS

Tracheas from HLA-A2+ C57BL/6 mice were heterotopically transplanted into C57BL/6 mice. Recipients were treated with neutralizing antibodies against tumor necrosis factor (TNF), interferon-gamma (IFN-gamma), or interleukin-1 (IL-1). Allograft histology as well as anti-HLA-A2 antibody development and T cell proliferative responses were determined at days +5, +15, +28, and +60.

RESULTS

Allografts in untreated and anti-IFN-gamma-treated recipients demonstrated full development of OAD by day +28. Allografts in anti-TNF-treated recipients showed no evidence of OAD, even at day +60. Allografts in anti-IL-1-treated recipients showed airway epithelium changes by day +28 but minimal evidence of OAD by day +60. Spleen cells from untreated and anti-IFN-gamma-treated recipients showed significantly higher proliferative responses to HLA-A2+ cells, compared with syngeneic recipients (negative controls). In contrast, anti-TNF and anti-IL-1-treated recipients showed significantly lower proliferative responses to HLA-A2+ cells, compared with untreated recipients. Development of anti-HLA-A2 antibodies was detected in all recipients by day +15, with the exception of those treated with anti-TNF.

CONCLUSION

Among the inflammatory cytokines, TNF seems to play a crucial role in the immunopathology of OAD developed after transplantation.

Acute correction of metabolic acidosis increases serum procollagen type I carboxyterminal propeptide in patients with chronic renal failure

BACKGROUND AND PURPOSE

Previous in vitro study has shown that an acidic medium increases osteoclastic and inhibits osteoblastic activity. The present study sought to determine the role of alkali therapy in osteoblast function in patients with chronic renal failure by assessing the serum concentration of procollagen type I carboxyterminal propeptide (PICP), a marker of bone formation, before and after bicarbonate infusion.

PATIENTS AND METHODS

Eighteen patients with chronic renal failure (creatinine clearance 12 +/- 6.6 mL/min) associated with mild to moderate metabolic acidosis were enrolled in this study. None had undergone dialysis. Metabolic acidosis was corrected by continuous bicarbonate infusion while plasma ionized calcium was clamped at the preinfusion level by calcium gluconate infusion throughout the procedure.

RESULTS

After bicarbonate infusion, there were significant increases in plasma pH (7.31 +/- 0.04 to 7.40 +/- 0.03, p < 0.001), bicarbonate concentration (18.46 +/- 2.49 to 23.66 +/- 2.72, p < 0.001), serum total calcium concentration (2.01 +/- 0.24 to 2.12 +/- 0.24 mmol/L, p < 0.001), and PICP concentration (137.3 +/- 56.25 to 159.6 +/- 57.30 micrograms/L, p < 0.05), whereas serum parathyroid hormone concentrations assessed by radioimmunoassay decreased significantly (153.7 +/- 88.6 to 111.5 +/- 78.7, p < 0.001). Serum ionized calcium concentrations showed no significant difference before and after bicarbonate infusion.

CONCLUSION

These results suggest that acute correction of metabolic acidosis improves osteoblast function and appear to underline the importance of maintaining normal acid-base homeostasis in chronic renal failure.

Western and Chinese antirheumatic drug-induced T cell apoptotic DNA damage uses different caspase cascades and is independent of Fas/Fas ligand interaction

Spontaneous or therapeutic induction of T cell apoptosis plays a critical role in establishing transplantation tolerance and maintaining remission of autoimmune diseases. We investigated the mechanisms of apoptosis induced by Chinese and Western antirheumatic drugs (ARDs) in human T cells. We found that hydroxychloroquine, Tripterygium wilfordii hook F, and tetrandrine (Tet), but not methotrexate, at therapeutic concentrations can cause T cell death. In addition, Tet selectively killed T cells, especially activated T cells. Although ARD-induced cytotoxicity was mediated through apoptotic mechanisms, Fas/Fas ligand interaction was not required. We further demonstrated that the processes of phosphatidylserine externalization and DNA damage along the ARD-induced T cell apoptotic pathway could operate independently, and that selective inhibition of DNA damage by caspase inhibitors did not prevent T cells from undergoing cell death. Moreover, we found that Tet- and Tripterygium wilfordii hook F-induced T cell DNA damage required caspase-3 activity, and hydroxychloroquine-induced T cell DNA damage was mediated through a caspase-3- and caspase-8-independent, but Z-Asp-Glu-Val-Asp-fluomethyl ketone-sensitive, signaling pathway. Finally, the observation that ARD-induced activation of caspase-3 in both Fas-sensitive and Fas-resistant Jurkat T cells indicates that Fas/Fas ligand interaction plays no role in ARD-induced T cell apoptosis. Our observations provide new information about the complex apoptotic mechanisms of ARDs, and have implications for combining Western and Chinese ARDs that have different immunomodulatory mechanisms in the therapy of autoimmune diseases and transplantation rejection.

Energy metabolism in exertional heat stroke with acute renal failure

BACKGROUND

Heat stroke is the clinical syndrome produced when the body overheats. It can develop in the army and in healthy civilian populations who physically exert themselves in a hot and humid environment during the summer, and may result in a significant number of heat-related deaths. Since strenuous exercise is one of the major exacerbating and precipitating factors, the incidence of exertional heat stroke (ExHS) is high among military personnel undergoing military training. Furthermore, acute renal failure (ARF) may occur in 25% of patients with ExHS and it can cause metabolic alterations that affect amino acid, carbohydrate, and lipid metabolism. Adequate nutritional support is essential for the treatment of ARF. The most important determinant of nutrient requirement in ARF is the degree of hypercatabolism caused by disease associated with renal function impairment. Indirect calorimetry (IDCM) is the method by which metabolic rate is estimated from measurements of oxygen consumption and carbon dioxide production. It can also provide information about the type and rate of substrate utilization in vivo (protein, carbohydrate, and fat).

METHOD

The present clinical study is a comprehensive analysis of metabolic changes which includes energy expenditure (EE) and substrate utilization in 10 patients with ExHS with ARF and 10 patients with exertional heat exhaustion (ExHE) by the use of IDCM.

RESULTS

Serum urea nitrogen, creatinine, peak creatine phosphokinase levels and heart rate were significantly increased in ExHS patients during ARF stage. Serum albumin levels were significantly decreased in ExHS patients with ARF. Resting energy expenditure (REE) was increased in patients with ExHS induced ARF and was not correlated with body temperature (r = 0.421). The average increase in EE during ARF stage was about 24%. The respiratory quotient in patients with ExHS induced ARF was lower than that in normal subjects and also in patients with ExHE. Urea nitrogen appearance rate increased in patients with ExHS induced ARF and in patients with ExHE without ARF. The percentage of total REE derived from fat in ExHS induced ARF and ExHE increased, while in patients with ExHS induced ARF and ExHE, the percentages of total REE derived from carbohydrate and protein were lower than those in control subjects.

CONCLUSIONS

The present results suggest that patients with exertional heat injury (both ExHS and ExHE) have hypermetabolism during the acute stage. Furthermore, patients with exertional heat-induced rhabdomyolysis and ARF have a moderately higher hypermetabolism than those without ARF during the acute stage. We believe that this mainly reflects a more pronounced reduction of the vital cell mass (muscle) in relation to body weight, and/or a compromised substrate oxidation in ExHS with ARF. Whether or not this subgroup of patients will require a higher energy/caloric support merits further investigation.

Infective endocarditis complicated with rapidly progressive glomerulonephritis: a case report

A 26-year-old man who had suffered from intermittent chills and fever over a two month period was quite clear of heart or kidney involved developed acute deterioration of renal function. A new pansystolic murmur over the apex of the heart was heard on auscultation, and echocardiography clearly showed a vegetation about 0.7-0.9 cm in size on the atrial site of the mitral value. Laboratory investigation displayed normochromic anemia with negative Coombs' test. Immunological studies were positive for rheumatoid factor and circulating immune complex. High serum levels of erythrocyte sedimentation rate and C-reactive protein, nephritic sediment of urinalysis and negative blood cultures for bacteria, tuberculosis or fungus were also noted. Abdominal sonography showed normal kidney size, bilaterally. Renal biopsy revealed typical crescentic glomerulonephritis. After intravenous penicillin therapy for two weeks, the serum creatinine level recovered from 6.7 mg/dl to 2.0 mg/dl and circulating immune complex disappeared. In consideration of cardiac insufficiency and the potential risk for complications of the vegetation, the patient underwent mitral valve replacement. Four weeks after operation, all the abnormal data had resolved completely. These data suggested that infective endocarditis with rapidly progressive glomerulonephritis is curable by antibiotic therapy and surgical intervention.

Cytokine production during hemodialysis: effects of dialytic membrane and complement activation

Interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) are closely associated with acute and chronic inflammatory processes in hemodialytic patients. However, the mechanisms concerning cytokine production by monocytes during hemodialysis are still conflicting. With the use of the more specific monoclonal antibody ELISA method, contamination detection and crossover protocol of complement-activating and noncomplement-activating hollow fibers, we were able to confirm augmented II-1 beta production by zymosan-stimulated monocytes with complement-activating hollow fiber as compared to noncomplement-activating hollow fiber before (1,411.9 +/- 865.7 +/- 149.9 pg/ ml/2 x 10(6) monocytes, p < 0.01). at the 15th minute (530.6 +/- 89.1 vs. 247.3 +/- 45.2 pg/ml/2 x 10(6) monocytes, p < 0.01) and at the end of dialysis (1,201.8 +/- 135.1 vs. 707.4 +/- 109.3 pg/ml/2 x 10(6) monocytes, p < 0.01). Similar results were observed with TNF-alpha production. IL-1 beta as well as TNF-alpha production decreased significantly at the 15th min of dialysis, thereafter they increased and approached the baseline levels towards the end of hemodialysis with both hollow fibers. Plasma C3a at the 15th minute correlated positively with postdialysis IL-1 beta and TNF-alpha production, while plasma C3a did not change in patients dialyzed with noncomplement-activating hollow fiber. Complement activation with complement-activating hollow fiber as well as monocyte-membrane interaction with complement-activating and noncomplement-activating hollow fiber might be involved in the pathogenesis of cytokine production during hemodialysis. Uremic toxin removal as well as stimulation of cytokine production inhibitor might contribute to the decreased cytokine production at the 15th minute of hemodialysis and monocyte-membrane interaction with or without complement activation resulted in augmented cytokine production toward the end of hemodialysis with both hollow fibers. We thus concluded that hollow fiber of bioincompatibility triggered much more cytokine production throughout the dialysis procedure.

Effect of calcitriol treatment on psoriasis in hemodialysis patient: a case report

The case of a 67-year-old man who has had psoriasis with multiple joints involvement for 30 years and renal failure for 1 year is described. He was admitted because of uremic symptoms and exacerbation of psoriasis. Hypocalcemia and low serum active 1.25(OH)2D3 were also observed. Hemodialysis, oral 1.25(OH)2D3 and CaCO3 supplement were employed. Interestingly, the psoriasis strikingly improved. The relationships among psoriasis, renal failure, 1.25(OH)2D3, serum calcium level and dialysis are discussed.

Influence of metabolic acidosis on serum 1,25(OH)2D3 levels in chronic renal failure

Metabolic acidosis has been shown to alter vitamin D metabolism. There is also evidence that calcium may modulate 1,25(OH)2D3 by a parathyroid hormone (PTH)-independent mechanism. To investigate the effect of rapid correction of chronic metabolic acidosis on serum 1,25(OH)2D3 levels by free calcium clamp in chronic renal failure, 20 patients with mild to moderate metabolic acidosis (mean pH 7.31 +/- 0.04) and secondary hyperparathyroidism (mean intact PTH 156.47 +/- 84.20 ng/l) were enrolled in this study. None had yet received any dialysis therapy. Metabolic acidosis was corrected by continuous bicarbonate infusion for 3-4 h until plasma pH was around 7.4, while plasma ionized calcium was held at the preinfusion level by calcium solution infusion during the entire procedure. The plasma pH, bicarbonate, total CO2, sodium, and serum total calcium levels were significantly increased while serum concentrations of alkaline phosphatase and albumin were significantly decreased after bicarbonate infusion. The plasma ionized calcium, potassium, serum magnesium, inorganic phosphorus, and 25(OH)D levels showed no significant change before and after bicarbonate infusion. The serum 1,25(OH)2D3 levels were significantly increased (38.66 +/- 11.77 vs. 47.04 +/- 16.56 pmol/l, p < 0.05) after correction of metabolic acidosis. These results demonstrate that rapid correction of metabolic acidosis raises serum 1,25(OH)2D3 levels in vitamin D-deficient chronic renal failure patients, and may underline the importance of maintaining normal acid-base homeostasis in the presence of secondary hyperparathyroidism in chronic renal failure.

A prospective study of calcium metabolism in exertional heat stroke with rhabdomyolysis and acute renal failure

Intensive training in a humid and warm environment can cause exertional heat stroke (ExHS) and rhabdomolysis (RBD) in military recruits. To investigate the role of vitamin D and monomeric calcitonin (CT) on the calcium metabolism in ExHS with RBD and acute renal failure (ARF), we studied 21 recruits with ExHS (mean age 21.4 years), 7 of which had ARF. Another 11 age-matched recruits with heat exhaustion (HE) and 11 healthy subjects were selected as controls. Our results showed that in 14 ExHS patients without ARF, mean serum creatinine (Cr) levels were significantly higher (151.16 vs. 106.08 mumol/l, p < 0.01), whereas serum osteocalcin (OC) levels were significantly lower (2.22 vs. 4.65 micrograms/l, p < 0.01) than in healthy controls. In 7 patients with ExHS and ARF, the mean serum Cr (774.38 vs. 105.20 mumol/l, p < 0.01), phosphorus (P) (2.26 vs. 1.26 mmol/l, p < 0.05), creatine phosphokinase (CPK) 274,143.97 vs. 85.78 IU/l, p < 0.05), intact parathyroid hormone (I-PTH) (299.81 vs. 18.66 ng/l, p < 0.05) and CT (13.58 vs. 6.63 ng/l, p < 0.01) levels on admission were significantly higher while the mean ionized calcium (iCa) levels were significantly lower than the healthy controls (0.9 vs. 1.18 mmol/l, p < 0.01). The mean serum 25-hydroxyvitamin D [25(OH)D] levels were not significantly different from healthy controls. However, mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] levels and the ratio of 1,25(OH)2D to 25(OH)D were significantly lower than healthy controls throughout the whole course of ARF. None of the 7 patients with ExHS and ARF developed hypercalcemia during the diuretic phase. Their mean serum I-PTH levels decreased significantly from 299 to 18 ng/l during the recovery phase (p < 0.05). Our study seems to suggest that the abnormal calcium metabolism in this unique patient group is in part caused by persistently decreased renal production of 1,25(OH)2D, although increased monomeric CT levels were associated with hypocalcemia. However, whether or not a causal relationship exists merits further investigation.

Effects of intravenous calcitriol on lipid profiles and glucose tolerance in uraemic patients with secondary hyperparathyroidism

1. Secondary hyperparathyroidism in chronic renal failure may contribute to abnormalities of lipid metabolism and glucose tolerance. Amelioration of secondary hyperparathyroidism has been reported to mitigate the hyperlipidaemia and improve glucose tolerance experimentally. 2. The effect of the partial suppression of hyperparathyroidism by intravenous calcitriol on lipid levels and glucose tolerance was studied in 15 haemodialysis patients with secondary hyperparathyroidism. All received intravenous calcitriol 1 microgram at the end of haemodialysis thrice weekly for eight weeks. Oral glucose tolerance test and plasma lipid profiles including triglyceride, total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apoprotein A-I and apoprotein B were determined simultaneously before and after eight weeks of therapy. 3. Before calcitriol treatment, uraemic patients with secondary hyperparathyroidism displayed a significant higher triglyceride and a significant lower HDL-C and apoprotein A-I as well as marked glucose intolerance with an increment of the area below the glucose curve when compared with healthy control subjects. 4. After eight weeks of calcitriol treatment, there was a significant decrement in serum intact parathyroid hormone (476.45 +/- 48.33 versus 191.37 +/- 30.17 ng/l, P < 0.001) and plasma triglyceride (2.24 +/- 0.34 versus 1.80 +/- 0.29 mmol/l, P < 0.05) as well as a significant increment of plasma apoprotein A-I (38.13 +/- 2.14 versus 44.19 +/- 2.18 mumol/l, P < 0.05), whereas there was no significant change in serum total cholesterol, LDL-C, HDL-C, and apoprotein B.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of intravenous calcitriol on platelet intracellular calcium in uremic hemodialysis patients with secondary hyperparathyroidism

BACKGROUND

To investigate the effect of the reversal of hyperparathyroidism on platelet intracellular free calcium ([Ca2+]i) by pharmacological parathyroidectomy with intravenous calcitriol in uremic patients with secondary hyperparathyroidism (2 degrees HPT).

METHODS

Serum concentrations of intact parathyroid hormone (I-PTH) were measured by two-site immunometric assay, and platelet [Ca2+]i was assessed using the fluorescent indicator fura-2. Fifteen hemodialysis patients with 2 degrees HPT and serum I-PTH 4 times greater than the normal upper limits, were selected for treatment with intravenous calcitriol 1 microgram thrice weekly for one month.

RESULTS

An increase of serum I-PTH (449.17 +/- 52.35 vs 32.52 +/- 1.95 pg/ml) and elevated platelet [Ca2+]i (139.49 +/- 8.78 vs 74.70 +/- 6.48 nM/L) was observed in uremic patients with 2 degrees HPT. Serum I-PTH levels were significantly correlated with platelet [Ca2+]i in uremic patients with 2 degrees HPT (r = 0.736, p = 0.002). The serum I-PTH levels decreased from 449.17 +/- 52.35 to 221.27 +/- 35.66 pg/ml (p < 0.001) and platelet [Ca2+]i fell from 139.49 +/- 8.78 to 97.86 +/- 7.25 nM/L (p < 0.001) after treatment. Fall in platelet [Ca2+]i was related to concomitant reduction in PTH levels (r = 0.572, p = 0.026).

CONCLUSIONS

It was concluded that an increase in cytosolic calcium in uremia may be at least in part induced by PTH. Besides, intravenous calcitriol can provide an effective way to suppress elevated serum I-PTH and attenuate platelet free calcium in uremia with 2 degrees HPT.

Imerslund-Grasbeck syndrome in a Chinese family with distinct skin lesions refractory to vitamin B12

Two brothers in a Chinese family with selective malabsorption of vitamin B12 associated with proteinuria (Imerslund-Grasbeck syndrome) presented with widespread mottled skin pigmentation, termed poikiloderma. In contrast to anaemia, this pigmentary disturbance remained unresponsive to vitamin B12 replacement. This is different from the reported hyperpigmentation sometimes seen in vitamin B12 deficiency which is reversible following treatment. As far as is known, an irreversible and persistent skin disorder has not been reported in this syndrome before.

Influence of rapid correction of metabolic acidosis on serum osteocalcin level in chronic renal failure

Metabolic acidosis induces a combination of inhibited osteoblastic and stimulated osteoclastic activity. To determine the role of alkali therapy in osteoblast function in chronic renal failure, serum bone isoenzyme of alkaline phosphatase (BAP) and osteocalcin were assessed before and after bicarbonate infusion. Eighteen patients with mild to moderate metabolic acidosis, none of whom had received dialysis therapy, were enrolled in this study. Metabolic acidosis was corrected by continuous bicarbonate infusion while plasma ionized calcium was monitored at 5 min intervals and held at the preinfusion level by calcium solution infusion during the entire procedure. The end-point of the study was reached when the plasma bicarbonate was approximately 24 mmol/l or pH was approximately 7.4 and plasma ionized calcium was clamped at the preinfusion level with only a 0.01 mmol/l fluctuation. The plasma pH (7.31 +/- 0.04 vs. 7.40 +/- 0.03, P < 0.001), bicarbonate (18.46 +/- 2.49 vs. 23.66 +/- 2.72 mmol/l, P < 0.001), serum total calcium, and osteocalcin (15.61 +/- 6.45 vs. 18.79 +/- 6.71 mg/l, P < 0.05) levels were significantly increased, whereas serum concentrations of alkaline phosphatase and albumin levels were significantly decreased after bicarbonate infusion. The serum BAP (1.85 +/- 1.29 vs. 1.79 +/- 1.18 mukat/l, P = 0.252), and inorganic phosphorus levels showed no significant differences before and after bicarbonate infusion. These results demonstrate that rapid correction of metabolic acidosis improves osteoblast function and may underline the importance of maintaining normal acid-base homeostasis in chronic renal failure.

Hyperparathyroidism, glucose tolerance and platelet intracellular free calcium in chronic renal failure

Disturbance in the vitamin D/parathyroid hormone (PTH) axis may be important in the pathogenesis of glucose intolerance and insulin resistance in uraemia. To investigate possible relationships between hyperparathyroidism, intracellular free calcium ([Ca2+]i), and glucose tolerance in chronic renal failure, we measured serum intact PTH (I-PTH) by two-site immunometric assay, platelet [Ca2+]i using the fluorescent indicator fura-2, and plasma glucose and insulin after 14 h overnight fast and at 30, 60 and 120 min following a 75 g oral glucose load, in 18 chronic haemodialysis patients with elevated serum I-PTH. Calcitriol (1 microgram) was administered parenterally at the end of each dialysis session for four weeks. This significantly decreased serum I-PTH (p < 0.001) and platelet [Ca2+]i (p < 0.01). Uraemic patients initially showed marked glucose intolerance, with increased area below the glucose curve compared to healthy controls, but after 4 weeks of calcitriol treatment, this effect was significantly decreased, and there was a significant rise in the area under the insulin curve after glucose load. The insulinogenic index also increased significantly after calcitriol treatment. These data suggest that calcitriol treatment of haemodialysis patient with secondary hyperparathyroidism is associated with increased insulin secretion in response to glucose challenge, and that this change is linked to the decrease in intracellular free calcium.

Rapid correction of metabolic acidosis in chronic renal failure: effect on parathyroid hormone activity

To investigate the effect of rapid correction of chronic metabolic acidosis on circulating intact parathyroid hormone (I-PTH) activity by free calcium clamp in chronic renal failure, 18 patients were enrolled in this study. Metabolic acidosis was corrected by continuous bicarbonate infusion while plasma ionized calcium was clamped at the preinfusion level throughout the entire procedure. The plasma pH, bicarbonate, total CO2, sodium, serum total calcium and 1,25(OH)2 vitamin D3 levels increased significantly while serum concentrations of I-PTH, alkaline phosphatase and albumin showed significant decreases after bicarbonate infusion. The plasma ionized calcium, potassium, serum magnesium and inorganic phosphorus levels showed no significant difference before and after bicarbonate infusion. These results demonstrate that rapid correction of metabolic acidosis attenuates circulating PTH activity in chronic renal failure and may underline the importance of maintaining normal acid-base homeostasis particularly in the presence of secondary hyperparathyroidism.

Role of plasma catecholamines, autonomic, and left ventricular function in normotensive and hypotension prone dialysis patients

The current study looked at plasma catecholamines, clinical autonomic function tests, and hemodynamic parameters in 10 ESRD patients (five men and five woman, aged 56.4 +/- 3.6) with dialysis hypotension and 10 patients (five men and five women, aged 58.6 +/- 4.2) without dialysis hypotension. Catecholamines were measured using high performance liquid chromatography--electrochemical detection (HPLC-ECD). Dialysis led to a significant decrease in mean arterial pressure (MAP) in the hypotensive group as compared with the normotensive group. Significantly higher basal (predialysis) plasma norepinephrine (NE) and dopamine levels (DA) were found in the hypotensive uremic group as compared with the normotensive group. Levels of plasma epinephrine (EP) were not significantly different between the normotensive and hypotensive groups. In response to postural stimulation, blood pressure fell in both groups, but the fall in the hypotensive group was significantly greater. Percentage increments of plasma catecholamines in response to postural stimulation in both groups were similar, however. Among the measured hemodynamic parameters, including total peripheral vascular resistance and left ventricular function (cardiac index and fractional shortening), only the cardiac index showed significantly lower values in the hypotensive group after dialysis, as compared with the normotensive group. Results of four tests of autonomic function indicated that although both groups responded similarly to hand-grip and cold-pressor tests, impaired responses to orthostasis and Valsalva maneuver after dialysis were observed in the hypotensive group. The MAP changes in dialysis in the hypotension prone group correlated inversely with predialysis plasma NE, but not with EP and DA.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of creatine phosphokinase in predicting acute renal failure in hypocalcemic exertional heat stroke

Recruits frequently develop hypocalcemia in exertional heat stroke (ExHS) with rhabdomyolysis and acute renal failure (ARF) from intensive training. It usually indicated severe skeletal muscle damage. However, the relative risk of ARF in ExHS patients complicated with hypocalcemia was unknown. The present study was undertaken to evaluate the value of peak serum creatine phosphokinase (CPK) level in predicting ARF in ExHS patients with hypocalcemia. Sixty-eight army recruits with ExHS were hospitalized at the Tri-Service General Hospital, Taiwan: 17 with ARF and hypocalcemia (group A); 7 with ARF but without hypocalcemia (group B); 20 without ARF but with hypocalcemia (group C); and 24 without ARF or hypocalcemia (group D). In the 24 patients with ARF (groups A and B) the serum phosphate and peak CPK levels were significantly higher than in patients without ARF (groups C and D; p < 0.001), serum calcium levels were also significantly lower in the former (p < 0.001). In the 37 patients with hypocalcemia (groups A and C), the peak serum CPK levels were significantly higher than in those without hypocalcemia (groups B and D; p < 0.001). There was a higher proportion of hypocalcemic patients with peak serum CPK levels greater than 10,000 U/l among ARF compared with patients without ARF (chi 2 = 12.48, p < 0.001). In 24 patients with ARF, there was a negative correlation between serum Ca and peak CPK levels (t = 3.37, r = -0.58, p < 0.01). However, a positive correlation was found between serum creatinine and peak serum CPK levels in 37 patients with hypocalcemia (t = 2.47, r = 0.39, p < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Systemic lupus erythematosus complicated with cystitis, obstructive uropathy and intractable diarrhea: report of a case

A patient with systemic lupus erythematosus (SLE) displayed an unusual extraglomerular syndrome of cystitis with obstructive uropathy and severe secretory-type diarrhea. She had a history of idiopathic hypothyroidism and thrombocytopenia. The intractable diarrhea and cystitis with severe urinary obstruction regressed with large doses of systemic and intravesical corticosteroid therapy. The possibility of SLE should be considered fin any young female patient who has diarrhea of an unknown cause and cystitis.

Effect of erythropoietin on neutrophil chemiluminescence in hemodialyzed patients

Erythropoietin (EPO) has been used widely for correcting anemia in hemodialyzed (HD) patients. Enhancement of phagocytic function during EPO treatment of HD patients has been studied, but no data have been available on the effect of EPO on neutrophil chemiluminescence (CL) after challenge with phorbol myristate acetate (PMA). CL was measured in prehemodialysis whole blood samples from 15 stabilized patients and 15 normal healthy control subjects (C) after challenge with PMA. Before EPO treatment, CL was noted to be significantly higher in HD patients than in C, which changed significantly after 5 weeks of treatment (Rx) and continued for 13 weeks of Rx. There was a significant increase in hematocrit in these HD patients after 5 weeks that persisted until the 13th week. It was concluded that there is a significant decrease in whole blood CL in response to challenge with PMA during correction of anemia in HD patients treated with EPO. This study demonstrated that EPO could decrease enhanced PMA-activated reactive oxygen metabolite production and suggested that this decrease may protect against tissue damage, including red blood cell hemolysis in the uremic milieu.

Displacements of backbone vibrational modes of A-DNA and B-DNA

We display the displacement vectors or eigenvectors of calculations of the A- and B-DNA backbones. These calculations are based on a refinement scheme that simultaneously fit several backbone modes of A-DNA, B-DNA, and A-RNA. We discuss the role of symmetry operations in mode calculations and the relevance of these displacement vectors to the interpretation of linear dichroism measurements performed on the A- and B-DNA helix.

Rapid analysis of bilirubin in neonatal serum. I. The binding of bilirubin to albumin

Evaulation of the severity of jaundice in the neonate may be determined by measuring the reserve binding capacity of serum proteins for free bilirubin. Determination of protein-bound bilirubin has been labor intensive, necessitating multiple runs on gel-permeation chromatography columns or, more recently, enzyme assays or fluorescence quenching analysis. We present a method for quantitation of free bilirubin and of bilirubin-binding capacity of serum by liquid chromatography. A gel-permeation column binds free bilirubin while allowing passage and quantitation of protein-bound bilirubin. Subsequent injection of a desorbing agent releases the adsorbed bilirubin from the column, permitting quantitation of free bilirubin. Bound and free serum bilirubin may be determined directly in less than 15 min using 10 microL of serum. The binding of bilirubin to neonatal serum is seen to be quite different from the binding to adult serum. Ion-exchange chromatography of adult and neonatal serum samples shows that their protein profiles are radically different. This difference probably accounts for the binding characteristics.

Rapid analysis of bilirubin in neonatal serum. I. The binding of bilirubin to albumin

Evaulation of the severity of jaundice in the neonate may be determined by measuring the reserve binding capacity of serum proteins for free bilirubin. Determination of protein-bound bilirubin has been labor intensive, necessitating multiple runs on gel-permeation chromatography columns or, more recently, enzyme assays or fluorescence quenching analysis. We present a method for quantitation of free bilirubin and of bilirubin-binding capacity of serum by liquid chromatography. A gel-permeation column binds free bilirubin while allowing passage and quantitation of protein-bound bilirubin. Subsequent injection of a desorbing agent releases the adsorbed bilirubin from the column, permitting quantitation of free bilirubin. Bound and free serum bilirubin may be determined directly in less than 15 min using 10 microL of serum. The binding of bilirubin to neonatal serum is seen to be quite different from the binding to adult serum. Ion-exchange chromatography of adult and neonatal serum samples shows that their protein profiles are radically different. This difference probably accounts for the binding characteristics.

Apparatus for rapid replica plating in rhizosphere studies

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