Growth and productivity of Haematococcus pluvialis and Coelastrella saipanensis by photosystem modulation for understanding the heterotrophic nutritional strategy for bioremediation application.

In this study, Haematococcus pluvialis and Coelastrella saipanensis were evaluated for heterotrophic nutrition potential in dairy waste medium by blocking the PSII using DCMU. The study was done by four sets of experiments. In the first set, in the different concentrations DCMU-treatments, 20µL showed pronounced effect in H. pluvialis and C. saipanensis as 89 % and 83% decrease in cells (>30 and > 250 cells/mL) compared to control (536 ± 12.35 × 104 and 1167 ± 15.35 × 104 cells/mL, respectively). Damage to the PS II by DCMU interrupted the growth, which in turn produced a significant drop in the number of cells. In the second round of experiment, growth of algae in various dairy waste concentrations suggest that dairy wastewater (DWW) provides enough nutrients to produce 35.71 % and 64.74 % more cells in H. pluvialis and C. saipanensis, respectively compared to the control. In the third set, high DCMU concentration was added to microalgae cultures in DWW to assess the heterotrophic nutrition potential. Growth in cell number 34.4 ± 19 and 617.46 ± 60.44 cells/mL was recorded in H. pluvialis and C. saipanensis when grown control medium whereas addition of DCMU reduced the cell number to 1.53 ± 0.75 and 55.13 ± 0.75 cells/mL on 15th day, respectively. This shows cells in cultures treated with DCMU reveal that algae can sustain their metabolic activity by utilizing the nutrients of dairy waste inhibiting photosystem. Fourth round of experiments found that microalgae could resume their growth and productivity by adapting to heterotrophic nutritional behaviour when DCMU given in mild dose at different time interval. This study conclude as C. saipanensis grows more readily by absorbing dairy waste nutrients than H. pluvialis. Therefore, C. saipanensis is an excellent choice for wastewater treatment through sustainable environmentally benign process after scale-up investigation. These results provide useful information to advance to molecular study for measuring microalgae's capability for bioremediation application.

Case Report: Primary De Novo Sarcoma In Transplant Pancreas Allograft.

BACKGROUND: The majority of malignancies after transplantation appear to be virally mediated and of recipient origin. Donor-derived neoplasms occur early, whereas recipient-origin tumors typically occur many years after transplantation. Sarcomas are a relatively rare form of cancer. The etiology of sarcomas remains largely unknown, although some are linked to viruses, familial cancer syndromes, or therapeutic radiation exposure. Primary sarcomas are extremely rare, accounting for <0.1% of all native pancreatic malignancies. The involvement of the allograft itself in the tumor is rare. CASE REPORT: A 53-year-old white woman (body mass index, 20.1 kg/m2) with a history of type 1 diabetes, chronic kidney disease, coronary artery disease, dyslipidemia, and pancreas-alone transplantation in 2007 was admitted with small bowel obstruction secondary to a mass in the head of the pancreas allograft, for which a laparotomy with allograft pancreatectomy was required. Histopathologic exam revealed a stage III high-grade unclassified spindle cell sarcoma positive for polyomavirus. After surgery, the patient was managed with close monitoring for disease recurrence. Her most recent scan was negative for recurrence at postoperative day 489. CONCLUSIONS: We report a previously unreported phenomenon of a soft tissue sarcoma arising in a pancreas allograft, likely of recipient origin and polyomavirus related. Standard treatment for sarcoma is wide excision of the tumor and close monitoring for recurrence. Systemic chemotherapy or radiotherapy is usually limited to advanced cases. Sarcomas may occur in a pancreas allograft. Allograft pancreatectomy and monitoring for recurrence is vital for a good outcome.

The effect of radial osteotomy on the position of the posterior interosseous nerve.

The purpose of this study was to determine whether a radial shaft fracture would decrease the protection provided to the posterior interosseous nerve by the pronation maneuver during posterolateral exploration. The position of the nerve in 14 cadaveric elbows, before and after a radial osteotomy, was determined using CT scans in full supination and full pronation after injection of the nerve with radio-opaque dye. The angle formed by the olecranon, radial head and posterior interosseous nerve, and the distance between the nerve and the most lateral aspect of the radial head were measured.Pronation increased the distance between the lateral radial head and the nerve by a mean of 6.5 mm (range 3.6-10.7). After radial osteotomy, the mean increase was 4.2 mm (range 1.0-8.3), difference 2.3 mm (p = 0.044, 95% CI 0.10 to 3.33). The posterolateral approach requires additional care in the presence of a radial shaft fracture, but pronation is still beneficial.

Nonredundant roles of the mPer1 and mPer2 genes in the mammalian circadian clock.

Mice carrying a null mutation in the Period 1 (mPer1) gene were generated using embryonic stem cell technology. Homozygous mPer1 mutants display a shorter circadian period with reduced precision and stability. Mice deficient in both mPer1 and mPer2 do not express circadian rhythms. While mPER2 regulates clock gene expression at the transcriptional level, mPER1 is dispensable for the rhythmic RNA expression of mPer1 and mPer2 and may instead regulate mPER2 at a posttranscriptional level. Studies of clock-controlled genes (CCGs) reveal a complex pattern of regulation by mPER1 and mPER2, suggesting independent controls by the two proteins over some output pathways. Genes encoding key enzymes in heme biosynthesis are under circadian control and are regulated by mPER1 and mPER2. Together, our studies show that mPER1 and mPER2 have distinct and complementary roles in the mouse clock mechanism.

Instability of the expanded (CTG)n repeats in the myotonin protein kinase gene in cultured lymphoblastoid cell lines from patients with myotonic dystrophy.

The mutation associated with myotonic dystrophy (DM) is the expansion of an unstable trinucleotide repeat, (CTG)n, in the 3'-untranslated region of the myotonin protein kinase gene. Although expanded repeats show both germline and somatic instability, the mechanisms of the instability are poorly understood. To establish a model system in which somatic instability of the DM repeat could be studied in more detail, we established lymphoblastoid cell lines (LBCL) from DM patients. Analysis of the DNA from DM LBCL using Southern blotting showed that the (CTG)n repeats were apparently stable up to 29 passages in culture. To study infrequent repeat size mutations that are undetectable due to the size heterogeneity, we established LBCL of single-cell origins by cloning using multiple steps of limiting dilution. After expansion to approximately 10(6) cells (equivalent to approximately 20 cell cycles), the DNAs of these cell lines were analyzed by the small pool PCR technique using primers flanking the (CTG)n repeat region. Two types of mutations of the expanded (CTG)n repeat alleles were detected: (1) frequent mutations that show small changes of the (CTG)n repeat size, resulting in alleles in a normal distribution around the progenitor allele, and (2) relatively rare mutations with large changes of the (CTG)n repeat size, with a bias toward contraction. The former may represent the mechanism responsible for the somatic heterogeneity of the (CTG)n repeat size observed in blood cells of DM patients. This in vitro experimental system will be useful for further studies on mechanisms involved in the regulation of the somatic stability of the (CTG)n repeats in DM.

Disruption of the adenosine deaminase gene causes hepatocellular impairment and perinatal lethality in mice.

We have generated mice with a null mutation at the Ada locus, which encodes the purine catabolic enzyme adenosine deaminase (ADA, EC 3.5.4.4). ADA-deficient fetuses exhibited hepatocellular impairment and died perinatally. Their lymphoid tissues were not largely affected. Accumulation of ADA substrates was detectable in ADA-deficient conceptuses as early as 12.5 days postcoitum, dramatically increasing during late in utero development, and is the likely cause of liver damage and fetal death. The results presented here demonstrate that ADA is important for the homeostatic maintenance of purines in mice.

Clinical experience with the Wiktor stent in native coronary arteries and coronary bypass grafts.

OBJECTIVES: To evaluate the results of implantation of Wiktor tantalum wire coronary stents in stenosed or occluded coronary vessels or in saphenous vein bypass grafts. DESIGN: A retrospective analysis of clinical and angiographic data from patients treated with tantalum wire stents implanted by one operator at two centres. PATIENTS: 52 patients undergoing conventional balloon angioplasty had 67 lesions treated by stents after acute or threatened closure of the target vessel, or because the lesions concerned were considered to be at particularly high risk of becoming restenosed, or because the result of primary angioplasty was inadequate. RESULTS: 65 of the 67 lesions were successfully stented although in two cases the first attempt failed and a second stent was then implanted successfully. There were no cases of stent occlusion and no myocardial infarctions in hospital or in the follow up period of 1-20 months. Eight patients had haemorrhagic complications that were minor in 4. One patient later had coronary bypass surgery after failure to stent a lesion. Angiographic follow up at a mean of 6 months after stenting showed restenosis associated with 4 of 47 stents studied. All patients with chest pain had had repeat angiography, and 84% of those without symptoms also agreed to reinvestigation after about 6 months. CONCLUSIONS: The Wiktor tantalum wire stent is an effective means of treating acute complications during angioplasty and seems to offer hope of a significant reduction in the rate of late restenosis in both native coronary vessels and saphenous vein bypass grafts. A prospective comparison of balloon angioplasty and stenting is needed.

Influence of the autonomic nervous system on circadian patterns of myocardial ischaemia: comparison of stable angina with the early postinfarction period.

OBJECTIVE: To compare the circadian rhythm of myocardial ischaemia in patients with stable angina with that in patients in the early postinfarction period with particular emphasis on the role of the autonomic nervous system. PATIENTS: 44 patients with stable angina and ischaemia on treadmill testing (group A) were compared with 131 patients in the early postinfarction period (group B). All had 48 hour ambulatory Holter monitoring. SETTING: Coronary care unit and cardiology department of a district general hospital. DESIGN: Prospective, between group, comparative study. RESULTS: 337 ischaemic episodes occurred in 35 patients in group A and 370 ischaemic episodes occurred in 65 patients in group B. 34% of patients in group A had only silent episodes of ischaemia compared with 97% in group B (p < 0.0001). In group A ischaemic episodes showed a circadian rhythm that peaked during the daytime hours (p < 0.0001), but this was not seen in group B. Both the high (0.15-0.40 Hz) and low (0.04-0.15 Hz) frequency spectral components of heart rate variability showed a clear circadian rhythm (p < 0.0001); peak values occurred during the sleeping hours, although this pattern was less pronounced in group B. The ratio of low to high frequency variability (a measure of sympathovagal balance) showed a peak in daytime hours in group A (p < 0.002), but this was not seen in group B. CONCLUSION: In stable angina, myocardial ischaemia peaks during the day and is associated with a similar circadian rhythm of sympathovagal balance. In the early postinfarction period both the ischaemic and sympathovagal rhythms are severely diminished or lost altogether. Circadian changes in sympathovagal tone may explain, at least in part, the circadian rhythm of ambulatory myocardial ischaemia in patients with stable angina.

Relation between heart rate variability early after acute myocardial infarction and long-term mortality.

The relation between both time and frequency domain analyses of RR variability and mortality was examined in a series of 226 consecutive patients with acute myocardial infarction admitted to 3 district hospitals in London. All patients underwent 24-hour Holter monitoring early after infarction (mean 83 hours, range 48 to 180), and time and frequency domain analyses of RR variability were performed using commercially available software. During an 8-month follow-up period (range 3 to 12 months), there were 19 cardiac deaths (8.4%). Time domain analysis confirmed reduced RR variability (SDRR, SDANN, SD) among nonsurvivors compared with survivors. However, there was no difference between the groups when the percentage of absolute differences between successive RR intervals > 50 ms (pNN50) and the root-mean-square of successive differences (RMSSD)--vagal measures of RR variability--were analyzed. Frequency domain analysis demonstrated a significant difference between those who died and the survivors when the low-frequency component--modulated by both vagal and sympathetic mechanisms--was analyzed; however, this was less marked when the high-frequency component--modulated by vagal activity--was analyzed. None of these measures of RR variability was related to infarct site or left ventricular ejection fraction. In conclusion, the data confirm the association between low RR variability and mortality after acute myocardial infarction. However, the mechanism does not appear to relate exclusively to decreased parasympathetic tone. The data suggest that the increased risk of early mortality associated with reduced RR variability reflects an imbalance in sympathovagal function that is unrelated to left ventricular function.

Hyperuricemia and urate nephropathy in urate oxidase-deficient mice.

Urate oxidase, or uricase (EC 1.7.3.3), is a purine metabolic enzyme that catalyzes the conversion of uric acid to allantoin in most mammals except humans and certain other primates. The loss of urate oxidase in the human during primate evolution predisposes man to hyperuricemia, a metabolic disturbance that can lead to gouty arthritis and renal stones. To create a mouse model for hyperuricemia and gout, and to address the question of whether urate oxidase is essential in lower mammalian species, we have disrupted the urate oxidase gene in the mouse by homologous recombination in embryonic stem cells. Unlike the human situation, urate oxidase deficiency in mice causes pronounced hyperuricemia and urate nephropathy. More than half of the mutant mice died before 4 weeks of age, indicating that urate oxidase is essential in mice. These mutant mice may also serve as animal models for hyperuricemia and its related nephropathy in humans.

Myocardial ischaemia and angina in the early post-infarction period: a comparison with patients with stable coronary artery disease.

OBJECTIVE: To evaluate Holter and treadmill responses in patients with stable angina or recent myocardial infarction in order to compare the mechanisms of ischaemia and its symptomatic expression in these two groups. PATIENTS: 75 patients with ischaemic ST segment depression on both a treadmill stress test and ambulatory Holter monitoring. Group A comprised 35 patients with stable angina, and group B comprised 40 patients in the early period after infarction. SETTING: The coronary care unit and cardiology department of a district general hospital. DESIGN: A prospective, between group, comparative study. RESULTS: Treadmill test showed demand driven ischaemia in both groups. Although ST depression occurred at comparable rate-pressure products and workloads, it was associated with angina in 80% of group A compared with only 40% of group B (p < 0.005). During Holter monitoring, ST depression was associated with an attenuated increase in rate in group A and almost no increase in rate in group B (18.2% v 3.7%; p < 0.005), suggesting that reductions in myocardial oxygen delivery were contributing to the ischaemic episodes, particularly in group B. Ischaemic episodes were more commonly silent during Holter monitoring, particularly patients in group B, only two of whom experienced angina in association with ST depression. Spectral and non-spectral measures of heart rate variability were significantly reduced in group B compared with group A. Patients with silent exertional ischaemia in group A had significantly less heart rate variability than patients who experienced angina but this difference was not seen in group B. CONCLUSION: In stable angina, myocardial ischaemia is usually painful and demand driven, whereas in the early period after infarction silent, supply driven ischaemia predominates. The failure of myocardial ischaemia to provoke symptoms in some patients with stable angina may be related to autonomic dysfunction affecting the sensory supply to the heart. In the early period after infarction despite clear evidence of autonomic dysfunction, other mechanisms must also be important as there was no tendency for the reduction in heart rate variability to be exaggerated in the subgroup with silent exertional ischaemia.

Construction of a defective retrovirus containing the human hypoxanthine phosphoribosyltransferase cDNA and its expression in cultured cells and mouse bone marrow.

Defective ecotropic and amphotropic retroviral vectors containing the cDNA for human hypoxanthine phosphoribosyltransferase (HPRT) were developed for efficient gene transfer and high-level cellular expression of HPRT. Helper cell clones which produced a high viral titer were generated by a simplified method which minimizes cell culture. We used the pZIP-NeoSV(X) vector containing a human hprt cDNA. Viral titers (1 X 10(3) to 5 X 10(4)/ml) of defective SVX HPRT B, a vector containing both the hprt and neo genes, were increased 3- to 10-fold by cocultivation of the ecotropic psi 2 and amphotropic PA-12 helper cells. Higher viral titers (8 X 10(5) to 7.5 X 10(6] were obtained when nonproducer NIH 3T3 cells or psi 2 cells carrying a single copy of SVX HPRT B were either transfected or infected by Moloney leukemia virus. The SVX HPRT B defective virus partially corrected the HPRT deficiency (4 to 56% of normal) of cultured rodent and human Lesch-Nyhan cells. However, instability of HPRT expression was detected in several infected clones. In these unstable variants, both retention and loss of the SVX HPRT B sequences were observed. In the former category, cells which became HPRT- (6-thioguanine resistant [6TGr]) also became G418s, indicative of a cis-acting down regulation of expression. Both hypoxanthine-aminopterin-thymidine resistance (HATr) and G418r could be regained by counterselection in hypoxanthine-aminopterin-thymidine. In vitro mouse bone marrow experiments indicated low-level expression of the neo gene in in vitro CFU assays. Individual CFU were isolated and pooled, and the human hprt gene was shown to be expressed. These studies demonstrated the applicability of vectors like SVX HPRT B for high-titer production of defective retroviruses required for hematopoietic gene transfer and expression.