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A field experiment was conducted to determine the population build-up of mustard aphid and their natural enemies in relation to abiotic factors at TCA, Dholi during the Rabi season of 2018-19 and 2019-20 respectively. The incidence of mustard aphid started in the 2nd and 3rd SMW of 2019 and 2020 respectively and reached maximum in 8th SMW in both the years. However, the predatory activity of coccinellids, syrphid larvae and spiders were started from 3rd SW with their peak activity at 3rd and 4th week of February in both the years. Mustard aphid population exhibited positive correlation with maximum temperature (0.347 & 0.543), minimum temperature (0.317 & 0.152) and negative correlation with relative humidity (-0.083 & -0.479) during 2019 & 2020 respectively and rainfall (-0.35) during 2020. However, natural enemies viz., coccinellids, syrphid larvae and spiders exhibited positive correlation with Tmax, Tmin, rainfall and negative correlation with RH in both the years.

The mechanisms underlying memory loss associated with Alzheimer’s disease and related dementias (ADRD) remain unclear, and no effective treatments exist. Fundamental studies have shown that a set of transcriptional regulatory proteins of the nuclear receptor 4a (Nr4a) family serve as molecular switches for long-term memory. Here, we show that Nr4a proteins regulate the transcription of a group of genes encoding chaperones that localize to the endoplasmic reticulum (ER), which function to traffic plasticity-related proteins to the cell surface during long lasting forms of synaptic plasticity and memory. Nr4a transcription factors and ER chaperones are linked to ADRD in human samples as well as mouse models, and overexpressing Nr4a1 or the ER chaperone Hspa5 ameliorates the long-term memory deficits in a tau-based mouse model of ADRD, pointing towards novel therapeutic approaches for treating memory loss. Thus, our findings establish protein folding in the ER as a novel molecular concept underlying long-term memory, providing new insights into the mechanistic basis of cognitive deficits in dementia.One-Sentence SummaryMolecular approaches establish protein folding in the endoplasmic reticulum as a novel molecular concept underlying synaptic plasticity and memory, serving as a switch to regulate protein folding and trafficking, and driving cognitive deficits in neurodegenerative disorders.

Комплексне дослідження впливу ширини забороненої зони активного шару та освітленості на продуктивність пристрою було проведено для перовскітного сонячного елемента (PSC) на основі FTO/TiO2/Cs2TiX6/CuSCN/Ag з використанням одновимірного симулятора ємності сонячних елементів (SCAPS-1D). Сучасна стратегія проектування пристрою для оптимізації струму короткого замикання (JSC, мА/см2), ефективності перетворення енергії (PCE, %) за рахунок зміни ширини забороненої зони поглинаючого шару та спектру освітленості була досліджена при оптимальних значеннях товщини, температури пристрою і щільності дефектів. Величини різних параметрів, використаних при моделюванні пристрою, було взято з попередньої роботи. Дане дослідження виявило, що для пристрою на основі поглинаючих шарів Cs2TiBr6 та Cs2TiF6 максимальне значення PCE спостерігається при ширині забороненої зони 1,80 еВ, тоді як для пристрою PSC на основі поглинаючих шарів Cs2TiI6 та Cs2TiCl6 максимальне значення PCE досягнуто при ширині забороненої зони 1,60 еВ. З іншого боку, оптимальне значення PCE можна досягти при освітленні з довжиною хвилі 400 нм для PSC на основі поглинаючих шарів Cs2TiBr6, Cs2TiI6 та Cs2TiF6. Для пристрою PSC на основі поглинаючого шару Cs2TiCl6 зафіксовано максимальне значення PCE при довжині хвилі 450 нм і різному освітленні. A comprehensive study on impact of active layer band gap and light illumination on the device performance has been analyzed for the FTO/TiO2/Cs2TiX6/CuSCN/Ag based Perovskite Solar Cell (PSC) using the Solar Cell Capacitance Simulator – 1 Dimension (SCAPS-1D) simulator. The present design strategy of the device for optimizing the short circuit current (JSC, mA/cm2), power conversion efficiency (PCE, %) through the absorbing layer band gap variation, and light illumination spectrum has been studied at the optimal thickness, device temperature, and defect density. The value of the different parameters used in the device simulation has been taken from the previous work. From this study, it was revealed that Cs2TiBr6, and Cs2TiF6 absorbing layer based PSC device has recorded maximum PCE at the 1.80 eV band gap, whereas, for the Cs2TiI6, Cs2TiCl6 absorbing layer based PSC device has achieved maximum PCE at the 1.60 eV band gap. On the other side, optimum PCE can be achieved at 400 nm wavelength on the light illumination for the Cs2TiBr6, Cs2TiI6, and Cs2TiF6 absorbing layer based PSC. The Cs2TiCl6 absorbing layer based PSC device has recorded maximum PCE at 450 nm wavelength on the different light illumination.

Background: Little is known about natural anti-SARS-CoV-2 antibody seroprevalence post COVID-19 and safety of vaccines in COVID-19 survivors with cancer. Methods: Among 2795 consecutive patients (pts) with COVID-19 and cancer registered to OnCovid between 01/2020 and 02/2021, we examined natural seroprevalence of anti-SARS-CoV-2 Antibodies (SC2Ab, IgM or IgG) in pts tested post-infection. We analysed prevalence and safety of SARS-Cov-2 vaccine administration in pts who underwent clinical re-assessment at participating institutions. Results: Out of 350 pts tested for SC2Ab, 318 (90.9%) had a positive SC2Ab titre post-convalescence. Neither baseline features (sex, age, comorbidities, smoking history, tumour stage/status, anticancer-therapy and primary tumour) nor COVID-19-specific features (complications, hospitalization, sequelae) were significantly associated SC2Ab status. Receipt of COVID-19 specific therapy was higher among SC2Ab+ pts (62.6% vs 40.6%, p=0.0156). Out of 593 pts with known vaccination status, 178 (30%) had received 1 dose, whilst 38 pts (6.4%) received 2 doses of mRNA based (70.2%) or viral vector vaccine (17.4%). Vaccinated pts were more likely aged ≥65 years (59% vs 48.3%, p=0.0172), with loco-regional tumour stage (56% vs 40.8%, p=0.0014), on anti-cancer therapy at COVID-19 (49.1% vs 38.2%, p=0.0168) and history of prior hospitalisation due to COVID-19 (61.8% vs 48.3%, p=0.0029). Vaccine-related adverse events were reported for 18/56 evaluable pts (32.1%) and included injection site reactions (50%), fever (44.4%), arthralgias (33.3%), fatigue (33.3%) and allergy (5.5%). No long-term vaccine-related morbidity was reported. Conclusions: We report high seroprevalence (>90%) of SC2Ab in convalescent cancer pts who survived COVID-19 irrespective of baseline demographics, oncological characteristics and COVID-19 severity. COVID-19 vaccines appear to be safe in cancer pts with history of prior infection. Clinical trial identification: NCT04393974. Legal entity responsible for the study: Imperial College London. Funding: Has not received any funding. Disclosure: D.J. Pinato: Financial Interests, Personal, Invited Speaker: ViiV Healthcare;Financial Interests, Personal, Invited Speaker: Bayer;Financial Interests, Personal, Advisory Board: Eisai;Financial Interests, Personal, Advisory Board: Amgen;Financial Interests, Personal, Advisory Board: BMS;Financial Interests, Personal, Advisory Board: Pfizer;Financial Interests, Personal, Advisory Board: Nanostring tech. A. Cortellini: Financial Interests, Personal, Advisory Board: MSD;Financial Interests, Personal, Advisory Board: BMS;Financial Interests, Personal, Advisory Board: Roche;Financial Interests, Personal, Invited Speaker: Novartis;Financial Interests, Personal, Advisory Board: SunPharma;Financial Interests, Personal, Invited Speaker: AstraZeneca;Financial Interests, Personal, Invited Speaker: Astellas. All other authors have declared no conflicts of interest.

A Substrate integrated waveguide (SIW) wideband band pass filter with 150 degree bend is presented in this paper. Attenuation of higher transmission frequencies are achieved by using array of I-shaped periodic band gap structures at the collinear arms. Six I-shaped slots (three in each arm) are etched over the top conducting layer to achieve the purpose. Several major parameters of these I-shaped structures are studied and presented with detailed outcome. Insertion loss 4GHz) is observed. The filter finds application in microwave X-band and Ku-band radar and satellite systems.

The effects of fireworks on air quality was assessed from the ambient concentrations of PM10, water soluble ionic species, metals and SO2 over Kolkata metropolis, India during Diwali festival in November 2010. PM10 concentrations on Diwali night were found to be ~5 times higher than the normal day night-time average. The increase in night-time concentrations of the metals on Diwali night spanned over a wide range (Al, Zn, Pb and Cd showed 5-12 times increases, Cu, Fe and Mn showed 25-40 times and Co and V showed 70-80 times) compared to normal night-time concentrations. The water soluble ionic species showed 1.5-6 times higher concentrations on Diwali night than on normal days. The most significant increases were found for K^+, Ca^2+, Mg^2+ and SO4^2-. The diurnal variations in PM10 and SO2 were also studied at one of the sites, and the results showed that their maximum concentrations were on Diwali night between 8 P.M.-3 A.M., indicating maximum firework activities during this period. PM10 and SO2 concentrations increased by ~5 times compared to those on normal days during this period at this site. The extensive use of firecrackers during Diwali festival thus leads to significant increases in these air pollutants, and since they are associated with serious, adverse health impacts, the use of fireworks during in this kind of festival in a highly populated city, like Kolkata, India, needs to be controlled.

The adequacy of setup margins for various sites in patients treated with helical tomotherapy was investigated. A total of 102 patients were investigated. The breakdown of the patients were as follows: Twenty-five patients each in brain, head and neck (H and N), and pelvis, while 12 patients in lung and 15 in craniospinal irradiation (CSI). Patients were immobilized on the institutional protocol. Altogether 2686 megavoltage computed tomography images were analyzed with 672, 747, 622, 333, and 312 fractions, respectively, from brain, H and N, pelvis, lung, and CSI. Overall systematic and random errors were calculated in three translational and three rotational directions. Setup margins were evaluated using van Herk formula. The calculated margins were compared with the margins in the clinical use for various directions and sites. We found that the clinical isotropic margin of 3 mm was adequate for brain patients. However, in the longitudinal direction it was found to be out of margin by 0.7 mm. In H and N, the calculated margins were well within the isotropic margin of 5 mm which is in clinical use. In pelvis, the calculated margin was within the limits, 8.3 mm versus 10 mm only in longitudinal direction, however, in vertical and lateral directions the calculated margins were out of clinical margins 11 mm versus 10 mm, and 8.7 mm versus 7.0, mm respectively. In lung, all the calculated margins were well within the margins used clinically. In CSI, the variation was found in the middle spine in the longitudinal direction. The clinical margins used in our hospital are adequate enough for sites H and N, lung, and brain, however, for CSI and pelvis the margins were found to be out of clinical margins.

A number of graphite–clay composites with varying percentages of graphite in the clay host have been prepared and their AC conductivities and dielectric behaviours have been studied in the frequenc...

We report here results from detailed timing and spectral studies of the high mass X-ray binary pulsar 4U 1538–52 over several binary periods using observations made with the Rossi X-rayTiming Explorer (RXTE) and BeppoSAX satellites. Pulse timing analysis with the 2003 RXTE data over two binary orbits confirms an eccentric orbit of the system. Combining the orbitial parameters determined from this observation with the earlier measurements we did not find any evidence of orbital decay in this X-ray binary. We have carried out orbital phase resolved spectroscopy to measure changes in the spectral parameters with orbital phase, particularly the absorption column density and the iron line flux. The RXTE-PCA spectra in the 3–20 keV energy range were fitted with a power law and a high energy cut-off alongwith a Gaussian line at $\sim 6.4 keV$, whereas the BeppoSAX spectra needed only a power law and Gaussian emission line at $\sim 6.4 keV$ in the restricted energy range of 0.3–10.0 keV. An absorption along the line of sight was included for both the RXTE and BeppoSAX data. The variation of the free spectral parameters over the binary orbit was investigated and we found that the variation of the column density of absorbing material in the line of sight with orbital phase is in reasonable agreement with a simple model of a spherically symmetric stellar wind from the companion star.

We have investigated the Quasi Periodic Oscillation (QPO) properties of the transient accreting X-ray pulsar XTE J1858+034 during the second outburst of this source in April-May 2004. We have used observations made with the Proportional Counter Array (PCA) of the Rossi X-ray Timing Explorer (RXTE) during May 14-18 2004, in the declining phase of the outburst. We detected the presence of low frequency QPOs in the frequency range of 140--185 mHz in all the RXTE-PCA observations. We report evolution of the QPO parameters with the time, X-ray flux, and X-ray photon energy. Though a correlation between the QPO centroid frequency and the instantaneous X-ray flux is not very clear from the data, we point out that the QPO frequency and the one day averaged X-ray flux decreased with time during these observations. We have obtained a clear energy dependence of the RMS variation in the QPOs, increasing from about 3% at 3 keV to 6% at 25 keV. The X-ray pulse profile is a single peaked sinusoidal, with pulse fraction increasing from 20% at 3 keV to 45% at 30 keV. We found that, similar to the previous outburst, the energy spectrum is well fitted with a model consisting of a cut-off power law along with an iron emission line., 17 pages, 8 figures and 1 table. Accepted in Journal of Astrophysics and Astronomy

Here we report the spectral characteristics of the high and low states of the pulsar 4U~0114+65 and examine the change in the parameters of the spectral model. A power law and a photoelectric absorption by material along the line of sight together with a high energy cut-off suffice to describe the continuum spectrum in both the states. A fluorescence iron line at $\sim$6.4 keV is present in the high as well as in the low state, though it is less intense in the latter. The photon index, cut-off energy and e-folding energy values hardly show any discernible change over the states. We compare these spectral characteristics as observed with ASCA to that with other satellites. We also compare the spectral characteristics of 4U~0114+650 with other X-ray sources which show intensity variation at different time scales., 14 pages, 4 figures and 2 tables. Accepted in Journal of Astrophysics and Astronomy

Uterine choriocarcinoma developing in patients beyond reproductive age is a rare occurrence. We report a case of choriocarcinoma of uterine corpus in a 54-yr-old woman after 7 yr of menopause and 25 yr after last child birth. She presented with pain in the abdomen, and on radiological investigation a left uterine adnexal mass of 3.4 x 2.8 cm size was detected. Her serum CA125 level was 40 mIU/mL (normal up to 35 mIU/mL). Hysterectomy revealed an intramural growth in left uterine cornu measuring 3.5 x 3.0 x 2.5 cm. Histological features of the tumor were consistent with choriocarcinoma, and immunohistochemistry detected strong reactivity for beta-hCG in the tumor cells. Serum beta-hCG level 4 wk after surgery was 1345 mIU/mL. The patient was put on combination chemotherapy (EMACO). She achieved serological remission but showed a rise in serum beta-hCG level 4 wk after completion of chemotherapy. We conclude that a high level of suspicion may help in preoperative diagnosis of uterine choriocarcinoma in the postmenopausal age group. However, the response to chemotherapy in these cases may not be as encouraging as in choriocarcinoma of reproductive age.

We present the timing and spectral properties of the transient Be/X-ray binary pulsar 3A 0535+262 during quiescence using three observations with the narrow field imaging instruments (NFI) of BeppoSAX. Assuming a distance of 2 kpc for this system, the 2-10 keV X-ray luminosities measured from the three observations are in the range of 1.5-4.0 $\times$ 10$^{33}$ erg s$^{-1}$, indicating a very low rate of accretion. We report the detection of pulsations at a very low luminosity of 2 $\times$ 10$^{33}$ erg s$^{-1}$ during one of the three observations, though at this accretion rate the system is expected to be in the centrifugally inhibited regime. The X-ray spectra for the unpulsed observations are best modeled as power law type while a combined model of power law and black-body is required to fit the pulsed spectrum., 13 pages, 6 figures, accepted in Astronomy and Astrophysics

We have investigated the orbital phase dependence of the X-ray spectrum of the High Mass X-ray Binary pulsar GX 301--2. Here we present the results from a spectral analysis of two sets of observations of GX 301--2 with the Rossi X-ray Timing Explorer (RXTE). Of particular interest are the variations of the absorption column density and the iron line flux along with other parameters of the spectral model with the orbital phase. We found that the X-ray spectrum can almost always be fitted with a partial covering absorption model. We have detected enhanced absorption near the periastron. However, the column density variation with orbital phase is not smooth, as is expected in a smooth stellar wind model. We discuss the results of the column density variation in the light of the two proposed models for GX 301-2, an equatorial disk emanating from the companion star Wray 977 and a gas stream following the neutron star. We also found that the iron K_alpha and K_beta line fluxes have peaks near the periastron and are well correlated with the continuum hard X-ray flux. The line equivalent width shows an interesting pattern with the column density, reasonably constant for low values of the column density and increasing rapidly beyond a certain value., Comment: 15 pages, 7 figures. accepted in Astronomy and Astrophysics

The discovery that PSA exists in serum in both free and complexed forms led to development of immunoassays specific for different PSA forms. This helped in measuring free PSA in the presence of PSA-ACT (PSA-alpha antichymotrypsin), hence it was possible to calculate the percent free PSA or free to total PSA ratio, measurement of which was helpful in reducing the number of unnecessary biopsies significantly, while maintaining a high clinical sensitivity for detection of cancer. The study was performed on 103 consecutive male patients (mean age 68 +/- 10.8 years SD) comprising of 90 patients with benign disease (87%) and 13 prostate carcinoma patients (13%), who had histologically proven prostate cancer. Patients with total PSA between 2-25 ng/ml were included in the study. 30 normal healthy males with age 58 +/- 10 years, served as control. Serum total PSA and free PSA were analyzed using streptavidin biotin EIA method (M/s Roche Diagnostics, Germany). The mean total PSA in normal healthy control subjects was 1.86 +/- 1.07 ng/ml. It was increased significantly in diseased condition. Its mean concentration in carcinoma patients was 12.6 +/- 5.3 ng/ml and in benign patients it was 6.3 +/- 4.6 ng/ml. The free to total PSA ratio in all the three groups was significantly different (p0.004) from each other. In carcinoma patients, mean f/t PSA ratio was 0.12 +/- 0.06 as compared to 0.21 +/- 0.11 and 0.28 +/- 0.17 in benign patients and in control respectively. The sensitivity and specificity of the test was calculated at different f/t PSA ratio cutoff. At 0.1 cutoff value, sensitivity of the test was 54% and specificity was 83%. The positive predictive value (ppv) was 32% and negative predictive value (npv) was 92%. From cutoff value of 0.12 to 0.16, sensitivity was increased from 54% to 85% but specificity was reduced from 78% to 67%. The ppv did not show much change and npv was increased from 92% to 97%. Increasing the cut off value thereafter showed no change in sensitivity but specificity was further reduced to 40%, therefore in this patient series, f/t PSA ratio cutoff of 0.16 was found to be the appropriate cutoff value. Combination of this ratio cutoff with other parameters like serum total PSA, DRE and TRUS helped in increasing the sensitivity of the test and this also helped in reducing the number of unnecessary biopsies. In 103 men who were biopsied, 13 (12.6%) prostatic carcinoma were identified. Among these 13 cancer patients, 9 patients had abnormal findings in DRE.7 individuals out of these 9, also had free to total PSA ratio lower than 0.16 and would have been biopsied and diagnosed anyway. If we use only f/t PSA ratio less than 0.16, to decide whom to biopsy, we would have biopsied and diagnosed 11/13 cases i.e. sensitivity of 85% but If we decide to biopsy those patients who had abnormal DRE and those who had low f/t PSA ratio, we could identify 13/13 carcinoma i.e. 100% sensitivity. Combining the f/t PSA ratio with total PSA, DRE and TRUS findings could help in reducing the number of unnecessary biopsies. 37 patients who were negative for malignancy having total PSA in the range of 5-20 ng/ml, normal DRE and TRUS findings, have been biopsied but with combination of total PSA in the range of 5-20 ng/ml, normal findings in digital rectal examination and TRUS and f/t PSA ratio more than 0.16 (cutoff), we could have avoided 16 biopsies which were unnecessary that means there was 43% reduction in unnecessary biopsies.

A 48-yr-old female presented with a 1-yr history of pain in the hypochondrium and epigastrium. All routine investigations and computed tomography (CT) of the abdomen were done. CT findings revealed a well-defined cystic mass in the right ovary, and ascitis with features suggestive of secondaries over the omentum and peritoneal surface. The serum CA125 was 1255 U/mL (normal range 0-35 U/mL), which was indicative of ovarian malignancy. An exploratory laparotomy was performed. Histopathological examination of organs revealed the presence of granuloma. The patient was advised to undergo antitubercular treatment (ATT) and follow-up every month. After 1 mo of ATT, the CA125 level came down to 42 U/mL, which was near normal. As tuberculosis requires only a conservative management, we suggest that in cases of abdominopelvic mass with or without ascitis, high serum CA125 should always raise a suspicion of tuberculosis and a laparoscopy combined with peritoneal biopsy should be performed to confirm the diagnosis. This will prevent unnecessary laparotomies. Moreover, serum CA125 can be used to monitor the response of disease to antitubercular treatment.

A 29-year-old young man presented with acute breathlessness. After investigative work-up he was found to have a massive pericardial tumour. Thoracotomy and near total surgical excision of the pericardial tumour was carried out. Histopathology and immunohistochemical markers study revealed it to be a synovial sarcoma arising from the left lateral pericardial surface. Postoperatively, he received external radiation and chemotherapy. Thirteen months after surgery he developed local recurrence which was unresectable.

Appropriate therapeutic measures can improve the life expectancy of patients with ovarian malignancy. There has been a pressing need for serodiagnostic assays to enable, the close patient monitoring. Cancer Antigen 125 (CA125) has been described as a useful marker in patient monitoring for ovarian malignancy. Keeping this in view, the present study was planned. 40 consecutive female patients of ovarian carcinoma (mean age 52.4±10.7 years) were selected for serum CA125 analysis during the period of year 1995-2001. The tumour marker concentration was compared with histologic types of ovarian tumour and the FIGO staging of the disease. 25 healthy females (mean age 35.2-10.4 years) served as control. Mean serum CA125 concentrations in patients with papillary serous adenocarcinoma(Mean±%CV 1571±121.5 U/ml) was much higher than patients with mucinous adenocarcinoma(775±78U/ml). Mean serum CA125 concentration in endometrioid carcinoma was very high(2853±136 U/ml). The patient with clear cell carcinoma however had shown moderate increase(60 U/ml). No correlation was found between serum CA125 concentration and the FIGO staging of disease.Quantitation of CA125 was most helpful in monitoring the response of treatment and followup of the patients after completion of their treatment. Posttherapeutically its concentration showed more than 50% reduction in almost all (91.4%) patients (P0.001). Importantly these patients had also shown significant regression of the disease clinically and radiologically. 8.6% of patients had shown static or increase in serum CA125 concentration which was associated with either clinically static or progressive disease. Recurrence of the disease was noted in patients who had shown increase in serum CA125 concentration (biochemical recurrence) in the followupHowever, in our test population biochemical recurrence(increase in serum marker concentration) preceded the clinical or radiological recurrence by an average of 6.5 months.Kaplan meier survival analysis for evaluation of overall survival in our test subjects showed an overall survival of 32% at one year and median survival of 9 months with confidence interval of 6.34 to 11.66. We conclude that serum CA125 is a useful marker for monitoring the treatment and predicting an early recurrence of the disease in ovarian carcinoma patients. A study in larger number of patients is needed to define its exact role in the management of the carcinoma ovary.

We describe a case of poorly differentiated adenocarcinoma of stomach, which did not present typical symptoms of gastrointestinal malignancy on first visit. The patient, a 62 year old smoker presented with shortness of breathe and pain in right lumbar region with no history of fever. Bone scans revealed multiple hot spots in skull, sternum, lumbar vertebrae and both iliac crests. A series of tumor markers were ordered which include PSA, CEA, CA19.9, CA 72.4 and AFP. Serum PSA and AFP concentrations were within normal range. Serum CEA and CA 72.4 were raised significantly. Markedly elevated levels of serum CA19.9 were found (>45000 U/ml) in this patient. CT chest and bronchoscopic examination ruled out the possibility of cancer lung. Upper GI tract endoscopy was done to find out lesion in GI tract. An ulcerative lesion was found in lesser curvature of stomach. Histopathological examination of endoscopic biopsy revealed a poorly differentiated adenocarcinoma of stomach. An unusually high serum CA19.9 (>45000U/ml) in case of gastric carcinoma has not been reported earlier.

In-vitro interaction of nitrofurantoin with V. cholerae DNA resulted in a quenching and red spectral shift of the drug absorption pattern. Scatchard analysis revealed that the drug binding involved more than one processes and that the strongest mode of binding was characterised by an association constant ( k ) of 5.04 × 10 6 M −1 and the number of binding sites per nucleotide ( n ) of 0.015. Based on viscosity measurements, the mode of drug binding to DNA appeared to be through intercalation, the helix unwinding angle of supercoiled plasmid pBR322 DNA being 10°. Nitrofurantoin binding to DNA resulted in an elevation of the thermal melting temperature ( T m ) of DNA by 6°C and inhibition of the action of DNase on DNA.

Since the introduction of hepatitis B immunoglobulin and nucleoside/nucleotide antivirals in the 1990's, outcomes of LT for hepatitis B virus (HBV)-related liver disease, regardless of whether for decompensated cirrhosis, hepatocellular carcinoma satisfying Milan criteria or fulminant hepatic failure (FHF), have been favorable with results comparable if not better to other liver transplant recipients. Unfortunately the same optimism does not hold true for hepatitis C which differs from post- transplant hepatitis B in many ways, most striking of which are the limited options for treatment of recurrent hepatitis C (HCV). As time has passed, the initial enthusiasm for liver transplantation for HCV has waned as the original excellent five year survival rates have now translated into disappointing medium- and long-term survival data. Cirrhosis can also develop in between 10-25% of patients by five years post-transplant which in turn has led to recurrent HCV-related cirrhosis emerging as an important yet controversial indication for retransplantation. A variety of diseases can cause FHF with drug-related hepatotoxicity, particularly from acetaminophen accounting for 50-60% of cases in United Kingdom and the United States while viral hepatitis appears to be declining as a cause. Although FHF is a relatively rare disease affecting approximately 2000 patients per year in the United States, it is associated with high morbidity and mortality without transplantation yet only 25% of patients in the United States undergo liver transplantation. This review article will discuss liver transplantation for HBV and HCV and will conclude with reviewing the etiology, epidemiology and management of FHF.

Our work focuses on a comprehensive orbital phase dependent spectroscopy of the four High Mass X-ray Binary Pulsars (HMXBPs) 4U 1538-52, GX 301-2, OAO 1657-415 & Vela X-1. We hereby report the measurements of the variation of the absorption column density and iron-line flux along with other spectral parameters over the binary orbit for the above-mentioned HMXBPs in elliptical orbits, as observed with the Rossi X-ray Timing Explorer (RXTE) and the BeppoSAX satellites. A spherically symmetric wind profile was used as a model to compare the observed column density variations. Out of the four pulsars, only in 4U 1538-52, we find the model having a reasonable corroboration with the observations, whereas in the remaining three the stellar wind seems to be clumpy and a smooth symmetric stellar wind model appears to be quite inadequate in explaining the data. Moreover, in GX 301-2, neither the presence of a disk nor a gas stream from the companion was validated. Furthermore, the spectral results obtained in the case of OAO 1657-415 & Vela X-1 were more or less similar to that of GX 301-2., 9 pages, 4 figures, Accepted for publication in Advances in Space Research

Repair-deficient and repair-proficient strains of E. coli K12 were sensitive to nitrofurantoin treatment to varying degrees with the double mutant strain (uvrA 6, recA 13) being most sensitive. Ultraviolet absorption data and thermal chromatography through a hydroxyapatite column revealed that nitrofurantoin treatment of V. cholerae strain OGAWA 154 produced a maximal amount of 55% reversibly bihelical DNA at a nitrofurantoin dose of 120 micrograms/ml/h, which indicated the formation of inter-strand cross-links in DNA. Nitrofurantoin also produced prophage-lambda induction in E. coli K12 strain GY 5027: envA, uvrB, ampA 1, strA (lambda), in a dose-dependent manner, the maximum induction being highly significant (P less than 0.001). Previously published mutation data coupled with the prophage induction data presented here suggest that the genotoxic properties of nitrofurantoin are mediated through the SOS pathway.

We report here discovery of the existence of two different accretion modes in the high mass X-ray binary pulsar Cen X-3 during its high states. The multiband X-ray light curves of Cen X-3 lasting for more than 3400 days obtained with the All Sky Monitor (ASM) onboard the Rossi X-ray Timing Explorer (RXTE) shows many episodes of high and low X-ray intensities. The high intensity phases last between a few to upto 110 days and the separation between two high intensity phases also varies widely. One remarkable feature deduced from the RXTE-ASM light curves is that during these high intensity phases, Cen X-3 manifests in two very distinct spectral states. When the source makes a transition from the low intensity phase to the high intensity phase, it adopts one of these two spectral states and during the entire high intensity phase remains in that particular spectral state. During December 2000 to April 2004, all the high intensity episodes showed a hardness ratio which is significantly larger than the same during all the high states prior to and subsequent to this period. It is also found that most of the soft outbursts reach a nearly constant peak flux in the 5--12 keV band. For comparison, similar analysis was carried out on the long term X-ray light curves of three other X-ray binary pulsars Her X-1, Vela X-1, and SMC X-1. Results obtained with these sources are also presented here and we found that none of the other sources show such a behaviour. From these observations, we suggest that Cen X-3 has two different accretion modes and in the course of nine years it has exhibited two switch overs between these., 5 pages, 5 postscript figures, accepted for publication in Astronomy and Astrophysics Letters

High Mass X-ray Binary Pulsars (HMXBP), in which the companion star is a source of supersonic stellar wind, provide a laboratory to probe the velocity and density profile of such winds. Here, we have measured the variation of the absorption column density along with other spectral parameters over the binary orbit for two HMXBP in elliptical orbits, as observed with the Rossi X-ray Timing Explorer (RXTE) and the BeppoSAX satellites. A spherically symmetric wind profile was used as a model to compare the observed column density variations. In 4U 1538-52, we find the model corroborating the observations; whereas in GX 301-2, the stellar wind appears to be very clumpy and a smooth symmetric wind model seems to be inadequate in explaining the variation in column density., Comment: 4 pages, 4 figures. To be Published in Elsevier/ASR

Benzoate hydroxylation test revealed that Cu(II) reacting with H2O2 produced OH degree radicals, which nicked or damaged DNA or hydroxylated benzoate, the extent of damage or hydroxylation depending on the period of incubation. The production of OH degree free radicals was also supported by the scavenger studies. Neither Cu(II) nor H2O2 alone could damage DNA or hydroxylate benzoate. EDTA-chelated Cu(II) plus H2O2 could damage DNA or hydroxylate benzoate only in presence of the biological reductant, L-cysteine, the damage increased with the increasing molar ratio of L-cysteine to Cu-EDTA. The biological relevance of the EDTA chelated Cu(II) and H2O2 system is discussed.

Nitrofurantoin caused a dose dependent inhibition of growth and decrease in viability of V. cholerae cells, the 10% (D10) and 37% (D37) survival doses being 50 and 19 micrograms/ml respectively. The drug at a concentration of 60 micrograms/ml caused 86% inhibition of DNA synthesis. Both light and electron microscopic observations revealed that treatment with nitrofurantoin (60 micrograms/ml for 1 hr at 37 degrees C) led to a significant filamentation of the V. cholerae cells, ultrastructure of the cell cytoplasm, plasma membrane and cell wall however remaining unaltered from those of untreated cells. The results are discussed in relation to DNA lesions produced by and the carcinogenic potential of the drug.

Pretreatment with sublethal doses of nitrofurantoin induced adaptive response in both Vibrio cholerae and Escherichia coli cells as indicated by their greater resistance to the subsequent challenging doses of the same drug. Adaptive response was maximum corresponding to pretreatment drug concentrations of 0.40 microgram/ml and 0.015 microgram/ml respectively for V. cholerae OGAWA 154 (wild type) and E. coli K-12 AB 2463 (recA-) cells. Adaptive response was inhibited by chloramphenicol (100 micrograms/ml) indicating the need of concomitant protein synthesis. Induction of adaptive response in recA deficient E. coli cells indicated that it was different from the conventional "SOS" response. Melting temperature of DNA of V. cholerae cells subjected to adaptive (0.4 microgram/ml for 1 hr) and challenging (120 micrograms/ml for 1 hr) doses of nitrofurantoin (76 degrees C) was closer to that of native DNA (75 degrees C) vis-a-vis DNA isolated from nonadapted and drug treated cells (77.5 degrees C). Also, DNA isolated from V. cholerae cells subjected to adaptive and challenging doses of the drug revealed the presence of fewer interstrand cross-links (16% reversible DNA) vis-a-vis DNA from nonadapted but drug treated cells (55% reversible DNA). Photomicrographic studies revealed that V. cholerae cells that were nonadapted but drug treated grew into long filamentous forms (4.25 +/- 2.97 micron) whereas those subjected to both adaptive and challenge doses of the drug exhibited much less filamentation (2.08 +/- 0.84 micron) vis-a-vis native cells (1.42 +/- 0.5 micron). Similar results on DNA melting temperature, cross-links in DNA, and filamentation of cells were obtained for E. coli AB 2463 (recA-) cells subjected to adaptive and challenging treatments with nitrofurantoin. Almost equal degree of resistance against nitrofurantoin could be induced in both V. cholerae OGAWA 154 (wild type) and E. coli strain PJ3 (AB 1157 ada-) when these cells were pretreated with nontoxic doses of hydrogen peroxide or nitrofurantoin. Evidence obtained in this work on the nature of the nitrofuratoin induced adaptive response with particular references to the oxidative and/or alkylating DNA damages were discussed. Nitrofuratoin induced adaptive response appeared similar to that elicited by furazolidone in V. cholerae cells and appeared to be directed towards oxidative and not alkylating adaptive repair pathway.

Nitrofurantoin inhibited growth and produced loss of viability of Vibrio cholerae cells in a dose-dependent manner, the 10% (D10) and 37% (D37) survival doses being 18.0 and 5.5 micrograms/ml x hr. respectively. The drug also caused filamentation of the cells in a very significant manner. Ultraviolet absorption data and thermal chromatography through hydroxyapatite column revealed that nitrofurantoin treatment of Vibrio cholerae cells produced a maximum amount of 55% of DNA reversibly bihelical due to the formation of inter-strand cross-links. Helix-coil transition studies carried out by viscometric and also, spectrophotometric methods revealed that the nitrofurantoin-induced cross-links in Vibrio cholerae DNA, imparted to this DNA greater thermal stability than that of native DNA. The quantitative aspect and also the mode of nitrofurantoin action on DNA of Vibrio cholerae and Escherichia coli cells vis-à-vis the carcinogenic potential of the drug were discussed.

Inbred mouse strain C57BL/6 pre-treated with or without the drug with suspected anticancer activity, DADH (N, N'-Diacetyl-1, 6-Diaminohexane) by daily feeding for five consecutive days to a total dose of 1 mmol of the drug in aqueous solution, were exposed to an acute dose of 1 Gy gamma radiation. Appropriate controls without radiation were maintained both for water and DADH-fed groups of animals. At 18 and 36 h post-irradiation the animals from all four groups (designated as A to D with each group having six animals) were sacrificed and their bone marrows were cultured for chromosomal analysis. Special emphasis was put on the estimation of the frequency of occurrence of extra chromosomal elements, such as minutes, single or double (DMS) as a possible assay for radiation-induced DNA amplification (presumably representing the proliferation specified genes(?) causing initiation of a very early tumourigenesis event). Gamma irradiation alone yielded the highest frequency of such minute chromosomal structures concerned (DMS), which was significantly reduced by DADH pre-treatment. The preliminary cytological data are discussed in the light of current information on DNA amplification pertaining to carcinogenic induction.

In a coordinated research programme sponsored by the Internation Atomic Energy Agency, the frequencies of chromocomal aberrations induced in peripheral blood lymphocytes (in vitro) by 250 kV X-rays at low doses (0.4, 1, 2, 3, 5, 10 and 30 rad) were determined. Blood from 2 donors was used to conduct one master experiment at these dose levels. The culture time used was 48 h and all samples including the controls were processed according to a standard protocol. The coded slides were scored by investigators from 10 participating laboratories. The main results are the following: (1) the frequencies of all types of chromosome aberrations at 0.4 rad are significantly lower than the control values; (2) there is no increase in the frequencies of dicentrics up to 2 rad and in those of terminal deletions up to 5 rad; (3) the mean frequencies of all aberrations considered together are not significantly different from one another at 1,2 and 3 rad ( P = 0.05); and (4) over the entire dose range the dose-effect relationship is clearly non-linear. A fit of these data to a linear quadratic model ( E ( D ) = c + αD + βD 2 ) showed that the observed total aberration frequencies at doses 1,2,3 and 5 rad are below the curve defined by the model. The deviations can be explained by an altered kinetics of aberration production at very low doses probably due to DNA repair mechanisms operating in these cells.

The results of an IAEA coordinated programme on radiation induced chromosomal aberrations in human peripheral blood lymphocytes in vitro are presented. In a master experiment, a whole blood sample from one donor was irradiated with 200 R of X-rays. Different fixation times from 46 to 82 h were used. The progression of cells into mitosis was monitored by BrdUrd incorporation. 14 investigators took part in the scoring of chromosomal aberrations. The main conclusions of this study are: (1) The mean frequencies of aberrations changed with fixation time. (2) The number of cells scored as aberrant by different laboratories was very similar, but there was variability in the number of aberrations scored per aberrant cell. (3) The differences in the frequencies of aberrations between laboratories were minimal when the scoring was restricted to the first major peak of mitotic activity and sufficient cells were scored. It is concluded that using controlled experimental conditions, human peripheral blood lymphocytes can effectively be used as a reliable biological dosimeter for absorbed radiation dose.

Fructose 2,6-bisphosphate (F 2,6-P(2)) was detected in the CAM species, Ananas comosus and Bryophyllum tubiflorum, and in C(3)- and CAM-Mesembryanthemum crystallinum. In both Mesembryanthemum tissues, F 2,6-P(2) was located outside the chloroplast. The levels of F 2,6-P(2), malate, starch, or soluble sugars were measured during various periods during the day-night cycle in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment, and in Bryophyllum, a species which stores carbon as starch in the chloroplast. In both species, the levels of F 2,6-P(2) were correlated with the stages of the day-night CAM cycle. Immediately following the dark-light transition the F 2,6-P(2) levels exhibited a rapid transient increase followed by a decrease. F 2,6-P(2) reached a daily minimum soon after the onset of deacidification and remained low until the malic acid pools approached their daily minima; the levels of F 2,6-P(2) then began a slow increase which accelerated during the period of afternoon CO(2) uptake. Immediately following the light-dark transition F 2,6-P(2) levels fluctuated. The levels were usually low after the fluctuations had ceased. The pools then increased as the rate of malate synthesis increased, remained at relatively constant high levels when the rates of malate synthesis were constant, and decreased as malate synthesis decreased towards the end of the dark period. The absolute levels of F 2,6-P(2) were always higher in Ananas than in Bryophyllum. The ratios of the activity of pyrophosphate fructose-6-phosphate l-phosphotransferase to cytoplasmic fructose 1,6-bisphosphatase and to phosphofructokinase were also far higher in Ananas than in Bryophyllum or in C(3)- or CAM-Mesembryanthemum.

An experiment sponsored by the International Atomic Energy Agency was undertaken to compare dose estimation by cytogenetic analysis on aliquots of samples of irradiated blood sent by air to participating laboratories. Accidental acute whole-body irradiations to 0.7 and 2.34 Gy and half-body irradiations to 3.5 Gy were simulated with X- and gamma-rays. For the partial irradiations the size of the irradiated fraction and its dose were estimated by the Qdr and contaminated Poisson techniques. Each laboratory's in vitro dose-response data were fitted to the quadratic model by the iteratively reweighted least squares method. Interlaboratory variations in dose-response curves, and in the aberration yields and dose estimates for the simulated accidents were noted. However, in general, most participants consistently obtained results acceptably close to the true values.