The atypical thioredoxin 'Alr2205', a newly identified partner of the typical 2-Cys-Peroxiredoxin, safeguards the cyanobacterium Anabaena from oxidative stress.

Thioredoxins (Trxs) are ubiquitous proteins that play vital roles in several physiological processes. Alr2205, a thioredoxin-like protein from Anabaena PCC 7120, was found to be evolutionarily closer to the Trx-domain of the NADPH-Thioredoxin Reductase C than the other thioredoxins. The Alr2205 protein showed disulfide reductase activity despite the presence a non-canonical active site motif 'CPSC'. Alr2205 not only physically interacted with, but also acted as a physiological reductant of Alr4641 (the typical 2-Cys-Peroxiredoxin from Anabaena), supporting its peroxidase function. Structurally, Alr2205 was a monomeric protein that formed an intramolecular disulfide bond between the two active site cysteines (Cys-38 and Cys-41). However, the Alr2205C41S protein, wherein the resolving cysteine was mutated to serine, was capable of forming intermolecular disulfide bond and exist as a dimer when treated with H2O2. Overproduction of Alr2205 in E. coli protected cells from heavy metals, but not oxidative stress. To delve into its physiological role, Alr2205/Alr2205C41S was overexpressed in Anabaena, and the ability of the corresponding strains (An2205+ or An2205C41S+) to withstand environmental stresses was assessed. An2205+ showed higher resistance to H2O2 than An2205C41S+, indicating that the disulfide reductase function of this protein was critical to protect cells from this peroxide. Although, An2205+ did not show increased capability to withstand cadmium stress, An2205C41S+ was more susceptible to this heavy metal. This is the first study that provides a vital understanding into the function of atypical thioredoxins in countering the toxic effects of heavy metals/H2O2 in prokaryotes.

Is mucormycosis the end? A comprehensive management of orbit in COVID associated rhino-orbital-cerebral mucormycosis: preserving the salvageable.

BACKGROUND: Rhino-orbital-cerebral mucor mycosis (ROCM) is a relatively rare opportunistic infection caused by the Mucorales species. While ROCM suggests involvement of the paranasal sinuses, orbit and brain ROM (rhino-orbital-Mucormycosis) stands for the fungal invasion in sinuses and orbit sans cerebral involvement. In India with the outbreak of the second COVID wave and the delta variant of the virus, there has been a steep increase in this opportunistic fulminant fungal infection, named COVID-associated Mucor mycosis (CAM). The most critical question in orbital management is when to go ahead with an exenteration. Our study aims to design a pertinent minimal invasive surgical protocol for surgeons to manage such cases based on our surgical experience and mitigate the need for exenteration and save the eyes wherever possible. METHODS: The study is a retrospective analysis of patients of ROM with and without brain involvement, who underwent minimal surgical management between March 2021 to March 2022 along with their follow-up. RESULTS: There were 184 eyes of 148 patients diagnosed with CAM. The mean age was 51.7 years with a male predominance of 103 (70%). All patients developed ROM following the COVID-19 infection and the duration between diagnosis of COVID-19 and ROM was 36 ± 23 days. 18 cases (12%) were bilateral. 76 eyes (41%) had no vision at the presentation. Imaging revealed paranasal sinus involvement (100%), orbital apex involvement (61%), cavernous sinus involvement (53%), and central nervous system (CNS) involvement (47%). All the patients (100%) were treated with systemic Liposomal amphotericin-B and sinus debridement. Endoscopic debridement of the orbital disease was performed in 45 (30.4%) cases, 15(8.1%) eyes underwent exenteration and were later rehabilitated with a customized ocular prosthesis, 103 (56%) eyes underwent transcutaneous retrobulbar amphotericin-B. At a mean follow-up of 13.1 months; the complete resolution was seen in 25 (17%) cases, the residual stable lesion was seen in 77(52%) of the cases and new lesions were developed in 13(9%) of the cases. Mortality was seen in 33 (22%) patients and all of them had CNS involvement. CONCLUSIONS: Systemic and protocol-based management can save the life and salvage the eyes.

Elucidation of the coping strategy in an OMP homozygous knockout mutant of Synechocystis 6803 defective in iron uptake.

The TonB-dependent outer membrane (OM) transporters import iron (Fe) under Fe-deficient growth conditions in the unicellular cyanobacterium Synechocystis sp. strain PCC 6803 (S. 6803 or WT). The present study characterises the mechanisms employed by a homozygous Δslr1908 (Slr1908, an OM protein) mutant of S. 6803 to adapt to intracellular iron deficiency imposed due to lack of Slr1908 when grown under Fe sufficient conditions for short (1 week) and long term (3 weeks). Although the homozygous Δslr1908 cells showed symptoms of stress such as slow growth, high ROS and altered ultrastructure, they were transcriptionally as well as translationally modulating their physiology to abrogate the Fe limitation. The mutant displayed only 20% of the Fe content in comparison to the WT after 1 week of growth, which increased to 50% by the end of the third week. The increase in intracellular Fe is ascribed to higher transcripts as well as corresponding protein of slr0042 which is the alternate OM route for Fe uptake. The mutant was also allocating its available Fe pools judiciously among Fe requiring proteins such as catalase, superoxide dismutase and cytochromes. The results elucidate the mechanism employed to tide over the Fe deficiency by Δslr1908 mutant and will be important in explaining the fine-tuning of Fe homeostasis in this model cyanobacterium.

Optimum dose of oral folic acid supplementation in transfusion-dependent thalassemia: a randomized controlled trial.

AIM AND OBJECTIVES: We compared the effect of different doses of oral folic acid (FA) supplementation (5 mg/day vs. 2.5 mg/day vs. 5 mg/week) on the proportion of children with folate excess (serum folate >20 ng/ml) and plasma homocysteine (Hcys) excess (>15 µmol/l) in transfusion-dependent thalassemia (TDT). MATERIALS AND METHODS: Children with TDT aged 5-18 years received oral FA in doses of 5 mg/day (Group 1), 2.5 mg/day (Group 2) and 5 mg/week (Group 3) for 9 months, after a wash-off period of 8 weeks. Folate levels (Serum and RBC) and plasma Hcys levels were measured after the therapy. RESULTS: Ninety children were randomized to receive one of the three interventions (30 per group). After wash-off period, the median serum folate levels were significantly lower and five children developed folate deficiency; the median [interquartile range (IQR)] serum folate levels (ng/dl) were comparable in the three groups [Group 1: 6.5 (3.3-14.2), Group 2: 5.1 (2.6-10.5) and Group 3: 4.8 (3.4-10.0)]. After 9 months of intervention, the median (IQR) serum folate levels (ng/ml) were comparable in all participants [Group 1: 18.0 (6.5-28), Group 2: 13.5 (6.4-24.5) and Group 3: 9.7 (5.3-22.5); p = 0.11]. Proportion of children with serum folate excess was 40%, 26.7% and 26.7% in Group 1, Group 2 and Group 3 (p = 0.48). Proportion of children with RBC folate excess was 92%, 86.7% and 86.7% in Group 1, Group 2 and Group 3 (p = 0.79). Hyperhomocysteinemia was seen in eight children with no significant difference between median Hcys levels in the groups (p = 0.75). CONCLUSION: Folic acid supplementation is recommended in TDT with 5 mg weekly dose being adequate.

Oxytocin infusion rates for maintaining uterine tone during non-elective cesarean section in laboring patients: a randomized, controlled trial.

PURPOSE: Oxytocin infusions for uterine tone maintenance are recommended following initial low oxytocin doses during cesarean section. Very limited literature is available on the optimal infusion rates in laboring patients who have been earlier exposed to oxytocin. METHODS: 105 patients, having received oxytocin for induction/augmentation of labor, received oxytocin infusions at rates of 2.5 IU/h (Group 2.5), 5 IU/h (Group 5) or 10 IU/h (Group 10) following 3 IU slow bolus. The primary outcome measure was estimated intraoperative blood loss; secondary outcome measures included uterine tone adequacy, requirements for additional uterotonics, and any side effects. Minor postpartum hemorrhage (PPH) was defined as blood loss > 500 ml and major/severe hemorrhage as blood loss > 1000 ml. RESULTS: Group 10 had minimum blood loss (311.1 ± 44.9 ml) and uterotonic requirements compared to other groups (p < 0.001). Group 2.5 had maximum blood loss (549.4 ± 74.3 ml) and uterotonic requirements; Group 5 had intermediate values (402.0 ± 49.5 ml). Twenty-six patients in group 2.5 had minor PPH against only one in group 5 and none in group 10 (p < 0.001). No patient in either group had major PPH. The incidence of hypotension was higher in group 10 than in group 2.5 (p = 0.004). Nausea and vomiting were also more frequent in group 10 than in the other two groups. CONCLUSION: Oxytocin infusions at 5 IU/h and 10 IU/h are more effective in reducing blood loss and preventing PPH than 2.5 IU/h. The dose of 10 IU/h, although the most efficacious, is associated with a high incidence of side effects. Hence, further studies are needed to find out the optimal maintenance infusion rate of oxytocin during cesarean section in laboring patients who have received oxytocin earlier.

A randomised double-blind comparison of phenylephrine and norepinephrine for the management of postspinal hypotension in pre-eclamptic patients undergoing caesarean section.

BACKGROUND: Studies comparing phenylephrine and norepinephrine for the treatment of postspinal hypotension in pre-eclamptic patients are limited. OBJECTIVE: To compare bolus doses of phenylephrine and norepinephrine for treating hypotension in pre-eclamptic mothers undergoing caesarean section under spinal anaesthesia. It was hypothesised that norepinephrine and phenylephrine use would be associated with similar neonatal outcome. DESIGN: Randomised controlled study. SETTING: Single centre, tertiary care, university teaching hospital, from December 2018 to March 2020. PATIENTS: A total of 86 women with pre-eclampsia and a singleton pregnancy who developed postspinal hypotension during caesarean section. INTERVENTIONS: Patients received intravenous phenylephrine (50 µg) or norepinephrine (4 µg) for treatment of hypotension, defined as a fall in baseline systolic BP by ≥ 20% or an absolute value < 100 mmHg. MAIN OUTCOME MEASURES: The primary outcome was umbilical artery pH. Secondary outcomes included Apgar scores, the number of hypotensive episodes, vasopressor requirements, the incidence of tachycardia/bradycardia/arrhythmias/hypertension and maternal complications. RESULTS: Umbilical artery pH was not different between the phenylephrine and norepinephrine groups (7.26 ±â€Š0.06 and 7.27 ±â€Š0.06, respectively; P = 0.903). The median [IQR] number of hypotensive episodes was higher in the norepinephrine than the phenylephrine group: 2 [1 to 3] vs 1 [1 to 2], respectively; P = 0.014. Apgar scores, total number of vasopressor boluses required, systolic BP trends and the incidence of maternal complications were comparable in the two groups. Heart rate (HR) values were lower in phenylephrine group (P = 0.026), and one patient in phenylephrine group and none in the norepinephrine group developed bradycardia (HR < 50 bpm), P = 1.000. CONCLUSIONS: In women with pre-eclampsia undergoing caesarean section, bolus doses of phenylephrine (50 µg) and norepinephrine (4 µg) used to treat hypotension after spinal anaesthesia are equally effective with similar neonatal and maternal outcomes. TRIAL REGISTRATION: CTRI/2018/11/016478.

Evaluation of maternal plasma platelet activating factor acetylhydrolase activity and mRNA expression in pre-eclampsia: a case control study.

Preeclampsia (PE) remains a leading cause of maternal morbidity and mortality all over the world. However, its aetiology and pathophysiology remain elusive. Platelet activating factor (PAF) is produced in response to oxidative stress and is a potent hypotensive agent. PAF acetylhydrolase (PAF-AH) inactivates PAF and is seen to decrease in normotensive women. The role of PAF-AH in preeclampsia has been in investigational literature, so far. The few studies done have shown a positive association of elevated levels of PAF-AH with preeclampsia. However, this marker has not been studied in the Indian population to-date and such studies are needed to elucidate the pathogenesis of this condition. Our study aimed to determine the PAF-AH activity by spectrophotometric assay in maternal plasma of 73 PE patients versus 73 normotensive controls and plasma PAF-AH mRNA expression to know the aberration of PAF-AH activity at the genetic level. Relative mRNA expression was calculated by Δ DCT method and a fold change was calculated by 2-ΔDCT. We found that the mean plasma PAF-AH activity levels among cases was significantly higher than the normotensive controls. However, the mRNA expression of the PAF-AH gene was similar between the cases and controls, as well as between severe and non-severe preeclampsia (true fold change =1). To conclude, PAF-AH appears to be increased in women with preeclampsia and hence may contribute to pathophysiology and severity. However, a larger sample size will be required to reiterate this association. Recently, PAF-AH inhibitors such as Darapladib has been tested as a therapeutic option in atherosclerosis. After studying the role of PAF-AH in the pathogenesis of PE, PAF-AH inhibitors may be used as a therapeutic tool in the future in PE.IMPACT STATEMENTWhat is already known on this subject? Platelet activating factor (PAF) is produced in response to oxidative stress and is a potent hypotensive agent. PAF acetylhydrolase (PAF-AH) hydrolyses and inactivates PAF and is seen to decrease in normotensive women. The role of platelet activating factor-acetylhydrolase (PAF-AH) in preeclampsia has been investigational so far. Few studies done have shown a positive association of elevated levels of PAF-AH in preeclamptic women.What do the results of this study add? Our study aimed to determine the activity of PAF-AH in maternal plasma of PE patients versus normal pregnancy and plasma PAF-AH mRNA expression to know the aberration of PAF-AH activity at the level of the gene. We found that plasma PAF-AH activity among preeclamptics was significantly higher than in the controls with a possible role in early-onset preeclampsia (<32 weeks), in the Indian population. This marker has never been studied in this population earlier. The results of our study re-emphasised its role in the pathogenesis of preeclampsia.What are the implications of these findings for clinical practice and/or further research? Such studies are important to not only give us a greater understanding of the various pathways involved in this multifactorial dreaded condition, but can also offer us a marker for early identification of women at risk. Recently, PAF-AH inhibitors like Darapladib has been tested as a therapeutic option in atherosclerosis. After studying the role of PAF-AH in the pathogenesis of PE, PAF-AH inhibitors may be used as a therapeutic tool in the future in PE.

Evaluation of Sigma-Metric and Application of Quality Tools in Clinical Laboratory of a Tertiary Care Hospital.

Variability in analytical performance of some analyte indicated the need of evaluation of quality plan of our laboratory. We tried to put the same degree of effort into our quality metrics as we put into the laboratory processes themselves. Application of six sigma methodologies improve the quality by focusing on the root causes of the problems in performance and analyzing by flowcharts, fishbone diagrams and other quality tools. Sigma metric was calculated for laboratory parameters for a period of 8 months during 2018-19. The analytes with poor sigma metric were free Thyroxine (FT3, FT4), Sodium, Calcium and Magnesium. Sigma metric of free Thyroxine (FT3, FT4), Sodium, Calcium and Magnesium were below 3. A road map for process improvement was designed with DMAIC (Define-Measure-Analyze-Improve-Control) model to solve the issue. Possible causes for low analytical performance of the particular analytes were depicted in Fishbone diagram. The Fishbone analysis identified the water quality issues with electrolyte analysis while high ambient temperature was culprit for poor assay performance of free Thyroxine. Sigma metric of the analytical performance was assessed once again after root cause analysis. Sigmametric showed marked improvement in control phase. Identification of problems led to reduction in non value added work leading to adequate resource utilization by addressing the priority issue. Therefore, DMAIC tool with Fish bone model analysis can be recommended as a well suited method for troubleshooting in poor performance of laboratory parameter.

The S-layer biogenesis system of Synechocystis 6803: Role of Sll1180 and Sll1181 (E. coli HlyB and HlyD analogs) as type-I secretion components for Sll1951 export.

Multiple secretion pathways are known for export of protein(s) forming the S-layer in bacteria. The unicellular model cyanobacterium Synechocystis sp. strain PCC 6803 (hereafter S. 6803) also possesses a well-defined S-layer composed of Sll1951 protein. However, the mechanism of its secretion is not completely understood. In the present study, the putative T1SS (Type I secretion system) components, Sll1180 and Sll1181 [inner membrane ABC transporter and membrane fusion protein (MFP), respectively] were characterized for their role in Sll1951 secretion. The corresponding ORFs i.e. sll1180 and sll1181 were inactivated by insertion of a spectinomycin resistance gene. The viability of the homozygous mutants of both the genes indicated dispensability of the corresponding proteins under the experimental conditions. Interestingly, the culture supernatants of the mutants i.e. Δsll1180 and Δsll1181, lacked Sll1951 as observed on SDS-PAGE and confirmed by mass spectrometry. Immunofluorescence delineated a distinct outer ring of Sll1951 in S. 6803 cells only that was further iterated by transmission and scanning electron microscopy. The loss of S-layer imparted an aggregative phenotype to both the mutants. Surprisingly, Δsll1181 cells showed increased sensitivity to different antibiotics indicating a role in multidrug efflux. This is the first report establishing Sl1180 and Sll1181 proteins as partners of the previously characterized Slr1270, for Sll1951 secretion and thus S-layer biogenesis in S. 6803. Sll1181 (in conjunction with Slr1270) also acts as MFP in multidrug efflux along with a yet uncharacterized inner membrane protein.

Role of Survivin and p53 Expression in Response of Primary Culture of Ovarian Cancer Cells to Treatment With Chemotherapeutic Agents.

BACKGROUND: Ovarian cancer is associated with a high relapse rate and is the fifth leading cause of cancer deaths in women. The genetic profile of a tumor is responsible for deciding response to chemotherapeutic agents. In this study, we investigate the relation between survivin and p53 expression and response to chemotherapeutic agents of primary cultures of ovarian cancer cells established from ascitic fluid. MATERIALS AND METHOD: Ascitic fluid and Dulbecco's modified Eagle medium was mixed in equal proportion in culture flasks and incubated to establish primary culture. The cells were treated with different combinations of carboplatin and paclitaxel with and without survivin small interfering RNA transfection. Cell survival was estimated by MTT assay. Survivin and p53 expression was quantified by real-time polymerase chain reaction. RESULTS: Out of 19 ascitic fluid samples, 13 primary cultures of ovarian cancer cells were established. The half maximal inhibitory concentration doses of carboplatin (≥70 µg/mL) and paclitaxel (≥18 µg/mL) were high for 10/13 and 5/13 patients, respectively. Survivin messenger RNA expression was significantly downregulated on treatment with carboplatin (100 µg/mL), paclitaxel (12.5 µg/mL), and a combination of carboplatin (50 µg/mL) and paclitaxel (6.25 µg/mL). Only paclitaxel-treated ovarian cancer cells showed decrease in expression of p53. Survivin small interfering RNA increased sensitivity of the primary cultures to chemotherapeutic agents. CONCLUSIONS: The present study highlights the fact that establishing primary cultures from ascitic fluid may help to develop personalized treatment regime for individual patients based on their molecular profile. Our study also shows that supplementing taxols drugs with survivin inhibitors may prove to be beneficial in the treatment of ovarian cancer patients.

Clinical predictors of treatment outcome in North Indian patients on antiepileptic drug therapy: A prospective observational study.

BACKGROUND: Nearly 40%-50% of the individuals fail to respond to first line antiepileptic drug (AED) monotherapy and 30% are refractory, which calls for the need to recognize predictive markers for treatment failure. This study aims to identify clinical factors predictive of a poor prognosis in patients on AED therapy. MATERIALS AND METHODS: A prospective follow-up study involving 1056 patients with epilepsy (PWE) aged 5-67 years from North India on phenytoin (PHT, n = 247), carbamazepine (CBZ, n = 369), valproate (VA, n = 271), phenobarbital (PB, n = 50), and multitherapy (MultiT, n = 119) was conducted between 2005 and 2015. Seizure and epilepsy types were diagnosed based on the classifications by the International League Against Epilepsy (ILAE). Patients remaining seizure-free during the past 1 year were assigned to the "no seizure" group and patients experiencing seizure recurrence were assigned to the "recurrent seizures" group. RESULTS: Of the total, 786 (74.4%) patients were successfully followed up with 60% achieving 1-year seizure remission. Seizure recurrence was observed in the remaining 40% of the patients with a high likelihood in patients with the disease onset at ≤5 years of age [55% vs. 38%, P = 0.0016, odds ratio (OR) = 2.02 (95% confidence interval (CI) = 1.31-3.13)], in patients with cryptogenic epilepsy than with idiopathic/symptomatic epilepsy (48% vs. 32%, P = 0.0049, OR = 1.61 [95% CI = 1.16-2.24]), and in patients with pretreatment seizure frequency ≥12/year (46% vs. 27%, P < 0.0001, OR = 2.21 [95% CI = 1.61-3.05]). Logistic regression analysis also revealed a significant association of seizure recurrence (P < 0.05) with the three variables. CONCLUSION: Our findings suggest that an early disease onset, cryptogenic epilepsy, and a higher pretreatment seizure frequency are related to a poor prognosis or poor remission in people with epilepsy (PWE) on AED therapy.

Multifactorial Analysis of a Biomarker Pool for Alzheimer Disease Risk in a North Indian Population.

BACKGROUND: Alzheimer disease (AD) is a progressive neurodegenerative disease with a complex multifactorial etiology. Here, we aim to identify a biomarker pool comprised of genetic variants and blood biomarkers as predictor of AD risk. METHODS: We performed a case-control study involving 108 cases and 159 non-demented healthy controls to examine the association of multiple biomarkers with AD risk. RESULTS: The APOE genotyping revealed that ε4 allele frequency was significantly high (p value = 0.0001, OR = 2.66, 95% CI 1.58-4.46) in AD as compared to controls, whereas ε2 (p = 0.0430, OR = 0.29, CI 0.07-1.10) was overrepresented in controls. In biochemical assays, significant differences in levels of total copper, free copper, zinc, copper/zinc ratio, iron, epidermal growth factor receptor (EGFR), leptin, and albumin were also observed. The AD risk score (ADRS) as a linear combination of 6 candidate markers involving age, education status, APOE ε4 allele, levels of iron, Cu/Zn ratio, and EGFR was created using stepwise linear discriminant analysis. The area under the ROC curve of the ADRS panel for predicting AD risk was significantly high (AUC = 0.84, p < 0.0001, 95% CI 0.78-0.89, sensitivity = 70.0%, specificity = 83.8%) compared to individual parameters. CONCLUSION: These findings support the multifactorial etiology of AD and demonstrate the ability of a panel involving 6 biomarkers to discriminate AD cases from non-demented healthy controls.

Ultrafast dynamics of the photo-excited hemes b and cn in the cytochrome b6f complex.

The dynamics of hemes b and cn within the cytochrome b6f complex are investigated by means of ultrafast broad-band transient absorption spectroscopy. On the one hand, the data reveal that, subsequent to visible light excitation, part of the b hemes undergoes pulse-limited photo-oxidation, with the liberated electron supposedly being transferred to one of the adjacent aromatic amino acids. Photo-oxidation is followed by charge recombination in about 8.2 ps. Subsequent to charge recombination, heme b is promoted to a vibrationally excited ground state that relaxes in about 4.6 ps. On the other hand, heme cn undergoes ultrafast ground state recovery in about 140 fs. Interestingly, the data also show that, in contrast to previous beliefs, Chl a is involved in the photochemistry of hemes. Indeed, subsequent to heme excitation, Chl a bleaches and recovers to its ground state in 90 fs and 650 fs, respectively. Chl a bleaching allegedly corresponds to the formation of a short lived Chl a anion. Beyond the previously suggested structural role, this study provides unique evidence that Chl a is directly involved in the photochemistry of the hemes.

Establishment of Primary Cell Culture From Ascitic Fluid and Solid Tumor Obtained From Epithelial Ovarian Carcinoma Patients.

OBJECTIVE: Ovarian cancer is the seventh leading cause of cancer death worldwide. This is mainly due to late diagnosis and high rate of relapse and resistance following chemotherapy. In the present study, we describe simple and cost-effective method to establish primary culture from ascitic fluid and solid tumor obtained from epithelial ovarian carcinoma patient, which may provide a better tool for in vitro testing of drug sensitivity and designing individualized treatment protocol. METHODS: Complete Dulbecco modified Eagle medium (DMEM) was prepared by supplementing DMEM with 10% fetal bovine serum and antibiotics (ciprofloxacin and amphotericin B). Establishment of primary culture of ovarian cancer cells from ascites fluid and solid tumor was done by using complete DMEM media. RESULTS: Primary cultures of ovarian cancer cells were established from ascitic fluid and solid tumor tissue. Of the 7 ascitic fluid samples, we were able to establish 5 primary cultures of ovarian cancer cells. All the 7 samples were diagnosed as serous papillary adenocarcinoma. Some fibroblasts were also attached to culture flask on day 4; they were removed by exposing them to trypsin for a brief period. On day 7, grape-like clusters were visualized under inverted microscope. The cells became confluent on the 10th and 11th day and showed cobblestone appearance, which is a hallmark of ovarian cancer cells. Senescent irregularly shaped cells that have ceased dividing were seen after 8 to 10 passages. CONCLUSION: This study highlights the fact that establishing primary cultures from ascitic fluid or solid tumor tissue may help us to understand the molecular profile of the cancer cells, which allow us to select the best chemotherapeutic agent for ovarian cancer patients and thus take a step toward patient-tailored therapy so that patients are not exposed to drugs to which they are not likely to respond.

Prediction of preeclampsia in primigravida in late first trimester using serum placental growth factor alone and by combination model.

We investigated a placental growth factor alone and combined clinical (mean arterial pressure, MAP), biophysical (uterine artery pulsability index, PI) and biochemical (placental growth factor, PLGF) model for predicting preeclampsia in late first trimester. The inclusion criteria was primigravida (<40 years) attending their first hospital visit with singleton pregnancy at 11-14 weeks of gestation. Of the enrolled and followed 291 subjects, 35 (12%) later developed PE (5.8%)/GH (6.2%). An equal number of randomised women with normotensive non-proteinuric course were considered as reference group. For preeclampsia, PLGF alone had detection rate of 40% and 51% with 5% and 10% FPR, respectively. On addition of MAP, the AUC improved to 0.937 for PE. Further, addition of mean PI slightly improved AUC to 0.965. This signifies that a model with all three markers had better prediction of preeclampsia rather than PLGF alone. Impact statement In view of high morbidity and mortality due to hypertensive disorders in pregnancy, there has been extensive research for developing markers to detect/screen the condition in early pregnancy. Several such markers have been tested in their individual capacities and in combination during early pregnancy. Most of these studies have originated from high income countries and focussed mainly on the second trimester of pregnancy. We investigated a placental growth factor alone and combined clinical (mean arterial pressure, MAP), biophysical (uterine artery pulsability index, PI) and biochemical (placental growth factor, PLGF) model for predicting preeclampsia in the first trimester in primigravida (<40 years). A nested case control model was used for our study. For preeclampsia, PLGF alone had detection rate of 40% and 51% with 5% and 10% FPR, respectively. On addition of MAP, the AUC improved to 0.937 for PE. Further, addition of mean PI slightly improved AUC to 0.965. The present study has been done in an Indian subcontinent setting (where maternal mortality related to preeclampsia are even higher) where very limited studies are available for the role of either PLGF or in combinations for prediction of preeclampsia. Our research pointed shows better predictability for PE when a combination of markers is used especially in low-risk nulligravida. These are easy, cheap and non-invasive measurements that can be taken in all women at their first routine antenatal visit.

A case report of rim enhancing lesion at the orbital apex.

We report a case of partial third nerve palsy resulting from a cystic lesion located at the orbital apex. Imaging was suggestive of cystic schwanomma but histopathology of the lesion confirmed epidermoid cyst, which is a rare tumour of the orbit.

Role of Iron and Copper in the Pathogenesis of Parkinson's Disease.

Parkinson's disease (PD) is an old age disorder of basal ganglia which involves oligomerization of α-synuclein protein and formation of intercellular inclusions known as "Lewy bodies" in substantia nigra and caudate nuclei in brain which is progressive in nature. It is second most prevalent neurodegenerative disorder characterized by tremor at rest, muscle rigidity, slowness of movement (bradykinesia, akinesia), and changes in posture (instability). Both excess and deficiency in levels of transition metals (especially iron, copper) can be detrimental to the central nervous system. Abnormalities in iron (Fe) and copper (Cu) metabolism have been reported to produce oxidative stress which is one of the major cause in pathogenesis of PD. In the present study 35 PD patients and 33 controls of Northern Indian population were included and serum levels of Fe, Cu and ceruloplasmin (Cp) were measured. Serum Fe (p < 0.01) and Cu (p < 0.01) levels were found to be significantly decreased in PD, whereas there was no significant change in Cp levels in PD patients as compared to controls. These results suggest the existence of a defect in iron which over the time, may hasten the entry of iron into the brain and decrease iron in the extracellular compartment in PD patients.

Photo-induced oxidation of the uniquely liganded heme f in the cytochrome b6f complex of oxygenic photosynthesis.

The ultrafast behavior of the ferrous heme f from the cytochrome b6f complex of oxygenic photosynthesis is revealed by means of transient absorption spectroscopy. Benefiting from the use of microfluidic technologies for handling the sample as well as from a complementary frame-by-frame analysis of the heme dynamics, the different relaxation mechanisms from vibrationally excited states are disentangled and monitored via the shifts of the heme α-absorption band. Under 520 nm laser excitation, about 85% of the heme f undergoes pulse-limited photo-oxidation (<100 fs), with the electron acceptor being most probably one of the adjacent aromatic amino acid residues. After charge recombination in 5.3 ps, the residual excess energy is dissipated in 3.6 ps. In a parallel pathway, the remaining 15% of the hemes directly relax from their excited state in 2.5 ps. In contrast to a vast variety of heme-proteins, including the homologous heme c1 from the cytochrome bc1 complex, there is no evidence that heme f photo-dissociates from its axial ligands. Due to its unique binding, with histidine and an unusual tyrosine as axial ligands, the heme f exemplifies a dependence of ultrafast dynamics on the structural environment.

Role of domain swapping in the hetero-oligomeric cytochrome b6f lipoprotein complex.

Domain swapping that contributes to the stability of biologically crucial multisubunit complexes has been implicated in protein oligomerization. In the case of membrane protein assemblies, domain swapping of the iron-sulfur protein (ISP) subunit occurs in the hetero-oligomeric cytochrome b6f and bc1 complexes, which are organized as symmetric dimers that generate the transmembrane proton electrochemical gradient utilized for ATP synthesis. In these complexes, the ISP C-terminal predominantly ß-sheet extrinsic domain containing the redox-active [2Fe-2S] cluster resides on the electrochemically positive side of each monomer in the dimeric complex. This domain is bound to the membrane sector of the complex through an N-terminal transmembrane α-helix that is "swapped' to the other monomer of the complex where it spans the complex and the membrane. Detailed analysis of the function and structure of the b6f complex isolated from the cyanobacterium Fremyella diplosiphon SF33 shows that the domain-swapped ISP structure is necessary for function but is not necessarily essential for maintenance of the dimeric structure of the complex. On the basis of crystal structures of the cytochrome complex, the stability of the cytochrome dimer is attributed to specific intermonomer protein-protein and protein-lipid hydrophobic interactions. The geometry of the domain-swapped ISP structure is proposed to be a consequence of the requirement that the anchoring helix of the ISP not perturb the heme organization or quinone channel in the conserved core of each monomer.

Critical appraisal of serum phenytoin variation with patient characteristics in a North Indian population.

CONTEXT: Phenytoin (PHT) is one of the frontrunner drugs used as monotherapy in the management of epilepsy. It is also one of the most common drugs causing adverse drug reactions (ADRs). The aim of this study was to study the relationship between serum PHT levels and the age, gender, dosage and genetic polymorphisms in a North Indian population. This knowledge will help in devising drug dosage schedules in various sub-groups of patients as well as in reducing its ADRs. MATERIALS AND METHODS: A retrospective analysis of data of 6224 patients from 1998 to 2009 receiving PHT alone for greater than (>) 4 weeks was performed. Patients suspected of being non-compliant, being overdosed or having a hepatic or renal disorder were excluded from the study. Two thousand eight hundred and eighty-eight patients fulfilling the inclusion criteria were divided into three groups: children (1-18 years), adults (19-60 years) and elderly (>60 years). RESULTS: There was a male preponderance (80%) in all the groups. A significant difference was found in the mean dose between children and adults as well as between children and elderly (P = 0.00). Also, there was a significant difference in the mean concentration and dose ratio between children and adults (P = 0.00). However, a negative correlation was observed between the daily dose and dose ratio (r = -0.36, P = 0.00) that was highest (r = -0.58, P = 0.00) in the elderly. There was a significant gender difference in the mean dose in both children (P = 0.03) and adults (P = 0.00), whereas the mean concentration differed in adults only. Every fifth patient was an intermediate metabolizer (IM) (CYP2C9FNx011/FNx013) and showed higher steady state drug levels (>17 mg/L) compared with extensive metabolizers (EMs) (<12 mg/L). The genetic difference between IM and EM was more prevalent in the dose ratio at maintenance dose, with a mean ± SD of 4.041 ± 1.288 mg/L/mg/kg in nine patients carrying the CYP2C9FNx011/FNx013 genotype compared with 2.145 ± 0.817 mg/L/mg/kg in 26 patients carrying the CYP2C9FNx011/FNx011 genotype (P = 0.00). CONCLUSION: North Indian female children and male adults frequently attain a higher serum concentration with the same dose when compared to the other groups. Absence of poor metabolizers may be responsible for a lower number of cases exhibiting toxicity in our population; however, this needs elucidation in a larger number of patients.